Today, we cover a subject full of air... the Respiratory System!
The Respiratory System
There are a couple of things we need to keep going. One is food, the other is air... primarily, oxygen. Oxygen is needed for the chemical reactions in our cells that give said cells energy.
The Respiratory System's primary purpose is to pull in air with oxygen, and expel air that has wastes out. It's the system behind breathing. Most of the time, the brain controls our breathing without our knowledge. We even forget we're doing it! All the same, we're doing it, and we need to... or we'll die.
It starts with either our nose or mouth. These are the ways air gets into the body. The nose, in fact, has mucus and hair that "cleans" the air coming in by trapping dirt and germs.
Then the air travels down the throat, past the larnyx (sp?), through the windpipe (called the trachea), into the bronchial tree. The bronchia (sp?) are the two big pipes that go into our lungs.
The lungs is where the next step takes place. These spongy bags are the primary part of the Respiratory System... also the most well-known. The lungs also big. They need to be, since they hold a ton of air-sacks called alveoli (sp?). And by "ton", I mean six million! If you spread these alveoli out, they would take up half of a tennis court!
But back to following the air through the Respiratory System. Air flows into the bronchial tree inside the lungs, until it reaches the bronchioles (sp?). These are tiny air-pipes inside our lungs. Each pipe ends in a bunch of sacks called alveoli (sp?), which are covered in tiny blood cells. These blood cells are so tiny, only one blood cell can pass through at a time! Through tiny holes in the alveolus (sp?; singular of alveoli [sp?]), blood cells give up the waste gas that is made in the cells' energy-making chemical process, carbon dioxide. Oxygen is taken out of the air, and then placed into the blood cells. The blood cells then travel back to the heart, and into the circulatory system (the energy/oxygen transport system in the body, along with the bloodstream), which is connected in this way to the Respiratory System.
Then we start the exit procedure. Basically, we go backwards through the whole system. There is sometimes an extra step, though. At the top of the trachea is the larnyx... AKA the voice-box. This is the area that contains the vocal cords. When air passes through these cords, it can make noise. When we use the vocal cords, our tongue, and mouth in sync, we can different noises and talk! And the vocal cords can adjust themselves to make higher or lower tones.
Of course, it goes much faster than what reading all that may make it seem like. And it needs to! The human body needs about a gallon of air a minute! That means we breathe over a couple thousand times a day... especially since our body isn't the greatest air-storage-device!
We have two lungs, as you may know. But did you know that one lung is smaller than the other? It's true! The left lung is smaller than the right lung. Why? Simple... the other must-have organ for life takes up some space, so the left lung has a "dent" in which this organ fits perfectly. Which organ am I speaking of? Why, the heart of course! They have to be close to work together anyway (since the heart is the part of circulatory system, and sends the blood through the lungs), and the left lung has a perfect-sized dent where the heart can lie as close as it can to its "business partners"!
The lung, being so important, needs protection. As well as the hairs and mucus in the nose, the trachea has many microscopic hair-like structures called cilia that helps to protect the lung. They catch dirt and dust, and keep them from getting into the lung, and causing problems.
In fact, this comes to the part about smoking. We all know smoking's bad. But how? Simple... the smoke kills the cilia. Then dirt and junk fill up the lungs, turning them from a healthy pink to more of a dirty black, since there's no cilia to protect them. Then cigeratte (sp?) tar (yep, there's tar there) starts blocking up the bronchioles (sp?) and parts of the bronchial tree. That causes trouble on its own, since it stops air from reaching its destination, and oxygen getting around the body! But smoking can cause lung cancer, in which lung cells go out of whack, and start growing out of control... literally growing out of control. I mean they started growing and multiplying, and, well... hello, lung cancer!
How do the lungs get air in and out? There's a muscle called the diaphragm which does this. It pulls and relaxes, making the lungs bigger and smaller. When the lungs are bigger, air rushes in. When smaller, air is pushed out. Some other muscles help, but the diaphragm is the primary one (as well as the most well-known).
Saturday, December 29, 2012
Friday, December 28, 2012
Medical Central: The Brain
It's time to check out the body's Control, Intelligence, and Head of Operation Center... the Brain!
The Brain
The Brain controls everything. It controls involuntary actions, sleep, hunger, and so on. And it's the part we use for thinking and making decisions. It's so important, the skull has a special part which protects it.
The Brain is our primary control center. There are actually a bunch of parts to it, all controlling different things. One part is actually a gland... the piturary (sp?) gland, which sends out hormones. These hormones control different stuff, like growth.
But there are three primary parts to the brain... the cerebrum, the cellebum (sp?), and the brain stem. The brain stem controls different involuntary actions... well, a lot of the brain does that. The cellebum (sp?) controls balance. And the cerebrum does a lot of stuff, including movement.
The cerebrum has two halves. For some unknown reason, the right half controls the left half of the body, and visa-versa! (sp?) And scientists think that these halves have specialities (sp?)... one half does more math and stuff, and the other specializes more in music and such stuff. But these two halves have a piece connecting them, so that each of them know what their counterpart is doing.
The brain is made of nerves (also known as neurons or neurones [sp?]). It is part of the nervous system, so that makes sense. It has nerves connected to it too, which it can control different parts of the body... and some don't even have to go down the other primary part of the nervous system (the spinal cord)! This is because some are connected directly to the face muscles, and some are connected to our arms and shoulders, so the visit into the spinal cord isn't always necessary.
There are three types of nerves... sensory neurons, motor neurons, and connector neurons. We can easily figure out sensory neurons... they're for carrying signals to the brain about our senses! Motor neurons are the ones that carry instructions to the muscles from the brain. And connector neurons are all the rest.
Nerves work by sending electrical signals. They receive them from the tentacles connected to the main body (which has its own control/processing center called the nucleus!), zap them down the protein-protected axon, then out the tentacles at the far end. Once the signal reaches here, neurons release a chemical, which the next neuron catches, translated into electricity, and zap! There goes the cycle all over again! But it happens extremely fast! Nerve signals move around 270mph! Whoa! So it makes sense that nerves receive a ton of signals! In a short amount of time, one nerve can receive about 100,000 signals! WOW!
Nerves are too small (or narrow) to see. Still, we know about the longest nerve... it goes from the spinal cord (which is part of the primary nervous system) to our toes! This nerve can be about 4 feet long! WOW!
Despite knowing how nerves work, we are still unsure totally of how the brain works. It's the best computer in existence... it does a zillion times better than any man-made computer today! The brain can compute, do calculations, make decisions, make memories, think, and control a ton of stuff... in less than a second! And this is all done by a bunch of connection-making and signal-sending and so forth by tons of nerves! The only computer that comes close to this organ is seen only in sci-fi movies and shows. Scientists are still studying the brain, and figuring out which part does what (brain scans helps), and so on.
And guess what? The part we use for thinking is only the surface of the cerebrum!!! It'll seem unlikely, but it's true! It's about 0.1 inch thick in most places, but this wrinkly brain-surface is pretty big. When spread out, it's as big as a newspaper! Wow!
The Brain
The Brain controls everything. It controls involuntary actions, sleep, hunger, and so on. And it's the part we use for thinking and making decisions. It's so important, the skull has a special part which protects it.
The Brain is our primary control center. There are actually a bunch of parts to it, all controlling different things. One part is actually a gland... the piturary (sp?) gland, which sends out hormones. These hormones control different stuff, like growth.
But there are three primary parts to the brain... the cerebrum, the cellebum (sp?), and the brain stem. The brain stem controls different involuntary actions... well, a lot of the brain does that. The cellebum (sp?) controls balance. And the cerebrum does a lot of stuff, including movement.
The cerebrum has two halves. For some unknown reason, the right half controls the left half of the body, and visa-versa! (sp?) And scientists think that these halves have specialities (sp?)... one half does more math and stuff, and the other specializes more in music and such stuff. But these two halves have a piece connecting them, so that each of them know what their counterpart is doing.
The brain is made of nerves (also known as neurons or neurones [sp?]). It is part of the nervous system, so that makes sense. It has nerves connected to it too, which it can control different parts of the body... and some don't even have to go down the other primary part of the nervous system (the spinal cord)! This is because some are connected directly to the face muscles, and some are connected to our arms and shoulders, so the visit into the spinal cord isn't always necessary.
There are three types of nerves... sensory neurons, motor neurons, and connector neurons. We can easily figure out sensory neurons... they're for carrying signals to the brain about our senses! Motor neurons are the ones that carry instructions to the muscles from the brain. And connector neurons are all the rest.
Nerves work by sending electrical signals. They receive them from the tentacles connected to the main body (which has its own control/processing center called the nucleus!), zap them down the protein-protected axon, then out the tentacles at the far end. Once the signal reaches here, neurons release a chemical, which the next neuron catches, translated into electricity, and zap! There goes the cycle all over again! But it happens extremely fast! Nerve signals move around 270mph! Whoa! So it makes sense that nerves receive a ton of signals! In a short amount of time, one nerve can receive about 100,000 signals! WOW!
Nerves are too small (or narrow) to see. Still, we know about the longest nerve... it goes from the spinal cord (which is part of the primary nervous system) to our toes! This nerve can be about 4 feet long! WOW!
Despite knowing how nerves work, we are still unsure totally of how the brain works. It's the best computer in existence... it does a zillion times better than any man-made computer today! The brain can compute, do calculations, make decisions, make memories, think, and control a ton of stuff... in less than a second! And this is all done by a bunch of connection-making and signal-sending and so forth by tons of nerves! The only computer that comes close to this organ is seen only in sci-fi movies and shows. Scientists are still studying the brain, and figuring out which part does what (brain scans helps), and so on.
And guess what? The part we use for thinking is only the surface of the cerebrum!!! It'll seem unlikely, but it's true! It's about 0.1 inch thick in most places, but this wrinkly brain-surface is pretty big. When spread out, it's as big as a newspaper! Wow!
Thursday, December 27, 2012
Medical Central: The Heart
Today's subject is something commonly known as the Heart. It is actually an organ. I've mentioned before that it has its own special muscle... cardiac muscle! But now let's explore the Heart a little more!
The Heart
The heart is primarily a big muscle, and a big pump. It pumps blood throughout our body, bringing food and oxygen to wherever it's needed. How does it do this? Like any other muscle, it contracts and relaxes. Plus, there's a valve system that helps a lot. There are two primary parts to the pump system: the atrium and the ventricle. Blood flows into the atrium, and then the ventricle. And then it leaves the heart for its primary destination.
There are two halves to the heart, with its own atrium and ventricle. There's even a piece of the heart called the septum that divides these halves! One side pumps used blood to the lungs to get cleaned and get an oxygen refill, and the other side sends oxygen-rich blood throughout our body.
How does the heart keep the blood going forwards instead of backwards and mixing things up? It's the valves! The valves open to let blood in, but close to keep the blood from taking a backwards trip. In fact, our heartbeat is actually the sound of the two valve sets closing... first the bigger set, and then the smaller set. Defective valves can be replaced via surgery... man-made valves for this purpose is made from pig fat. Sounds disgusting, I know, but it's a still-cool way of using stuff.
The heart, believe it or not, has its own mini-blood system that brings it blood and nutrients. You've got to remember that the heart is a muscle that works 24/7 without any breaks, so the stuff is needed. Now, the passages can get blocked... usually by a blockage of blood vessels called a blood clot. The muscle stops receiving what it needs, and dies... and that causes trouble. This problem is extremely well-known, especially by its name of heart attack!
The heart has a lot of blood vessels attached to it, whether the blood is being sent in or out. One of these is the atora (sp?), which is very strong! It can stand high pressure from the blood! This makes some sense, since it's one of the primary blood vessels.
Did you know that your heart has a skin too? It's true! The heart has a skin called the parcardium (sp?). This skin is a little different from our normal skin. It's two "bags" over the heart! Still, it's cool!
The Heart
The heart is primarily a big muscle, and a big pump. It pumps blood throughout our body, bringing food and oxygen to wherever it's needed. How does it do this? Like any other muscle, it contracts and relaxes. Plus, there's a valve system that helps a lot. There are two primary parts to the pump system: the atrium and the ventricle. Blood flows into the atrium, and then the ventricle. And then it leaves the heart for its primary destination.
There are two halves to the heart, with its own atrium and ventricle. There's even a piece of the heart called the septum that divides these halves! One side pumps used blood to the lungs to get cleaned and get an oxygen refill, and the other side sends oxygen-rich blood throughout our body.
How does the heart keep the blood going forwards instead of backwards and mixing things up? It's the valves! The valves open to let blood in, but close to keep the blood from taking a backwards trip. In fact, our heartbeat is actually the sound of the two valve sets closing... first the bigger set, and then the smaller set. Defective valves can be replaced via surgery... man-made valves for this purpose is made from pig fat. Sounds disgusting, I know, but it's a still-cool way of using stuff.
The heart, believe it or not, has its own mini-blood system that brings it blood and nutrients. You've got to remember that the heart is a muscle that works 24/7 without any breaks, so the stuff is needed. Now, the passages can get blocked... usually by a blockage of blood vessels called a blood clot. The muscle stops receiving what it needs, and dies... and that causes trouble. This problem is extremely well-known, especially by its name of heart attack!
The heart has a lot of blood vessels attached to it, whether the blood is being sent in or out. One of these is the atora (sp?), which is very strong! It can stand high pressure from the blood! This makes some sense, since it's one of the primary blood vessels.
Did you know that your heart has a skin too? It's true! The heart has a skin called the parcardium (sp?). This skin is a little different from our normal skin. It's two "bags" over the heart! Still, it's cool!
Sunday, December 23, 2012
Medical Central: Organs
Today's topic is on a important set of parts within the body. So important and so interconnected, that if one goes "off" permanently, we die! Today we talk about... organs!
Organs
Before the last post, I mentioned that our Skin is an organ. But what's an organ? It's a part of the body that has at least two tissues combined... like muscle and nerve tissue. Usually, these tissues band together for a single purpose, and then they're called an organ.
We've got lots of organs. I mentioned Skin before, and some of the better-known ones are the heart, kidneys, and the stomach. There are some less-well-known ones, like the pancreas (while makes stuff for digestion) and the gallbladder (makes bile, which helps in digestion). The nutrient-absorbing intestines are organs too. Some organs, like the liver, multitask (though the liver primarily does digestion). Though some are really only doing one thing (the heart pumps blood which gives us energy, for example). Some organs even have similar jobs (the spleen and the kidneys are both cleaners, for example). Some do their jobs in interesting ways... the spleen, for example, cleans blood by removing no-longer-active cells. One famous organ is in charge of keeping other organs on the go... you know what I'm talking about: the brain!
Organs work together in systems. These are called "organ systems" usually do one big thing, with their own organs. The skeletal systems, the respiratory system, the circulatory system, and the digestive system are some examples of organ systems. However, these systems can't work alone. They all need each other to keep going!
Even if one organ's lights go out... good-bye person! However, technology has gotten so advanced, that we can either replace many of the organs, or assist them in their jobs so that they don't go out (and, therefore, we don't go out). Organs that are being used as replacements are kept and transported in special containers that keep the organ cold and sterile (AKA, germ-free and clean!). And these replacement organs can now be kept outside of the body for long periods of time if everything's done right! For example, now a replacement kidney can be kept outside of the body for days if everything's done right! Wow!
Organs
Before the last post, I mentioned that our Skin is an organ. But what's an organ? It's a part of the body that has at least two tissues combined... like muscle and nerve tissue. Usually, these tissues band together for a single purpose, and then they're called an organ.
We've got lots of organs. I mentioned Skin before, and some of the better-known ones are the heart, kidneys, and the stomach. There are some less-well-known ones, like the pancreas (while makes stuff for digestion) and the gallbladder (makes bile, which helps in digestion). The nutrient-absorbing intestines are organs too. Some organs, like the liver, multitask (though the liver primarily does digestion). Though some are really only doing one thing (the heart pumps blood which gives us energy, for example). Some organs even have similar jobs (the spleen and the kidneys are both cleaners, for example). Some do their jobs in interesting ways... the spleen, for example, cleans blood by removing no-longer-active cells. One famous organ is in charge of keeping other organs on the go... you know what I'm talking about: the brain!
Organs work together in systems. These are called "organ systems" usually do one big thing, with their own organs. The skeletal systems, the respiratory system, the circulatory system, and the digestive system are some examples of organ systems. However, these systems can't work alone. They all need each other to keep going!
Even if one organ's lights go out... good-bye person! However, technology has gotten so advanced, that we can either replace many of the organs, or assist them in their jobs so that they don't go out (and, therefore, we don't go out). Organs that are being used as replacements are kept and transported in special containers that keep the organ cold and sterile (AKA, germ-free and clean!). And these replacement organs can now be kept outside of the body for long periods of time if everything's done right! For example, now a replacement kidney can be kept outside of the body for days if everything's done right! Wow!
Saturday, December 22, 2012
Medical Central: Swimming & Exercise
I mentioned last time that skin is waterproof. Well, the body has some other devices that have to be put into action when swimming... or other stuff!
Swimming & Exercise
Everyone knows we have to exercise to get fit. But how come? The body is a machine... an amazing machine extremely well-put together! But, while it does fine on a day-to-day basis, training can make it work better. The different components will work together smoother, and the muscles themselves will get stronger.
Also, healthy eating will increase the muscles' strength and efficiency. Why? Muscle make energy from oxygen and glucose... which explains why the heart beats faster during exercise time (to transport these items more quickly). But exercise can help make longer-lasting energy supplies, and if the lung muscles are strengthened, they can expand to take even more air (and therefore, oxygen) when needed!
Back to the "machine" part. The body parts can work together in many different ways, and those ways can sometimes be complicated. Take swimming, for example! Our feet can act as flippers... but that starts with an action from higher up our leg! And the hips roll in response to the movement of our arms! And even the propelling motion of our arms are controlled by two different muscles... the deltoid (sp?) shoulder-muscle and one in our arm! The muscle pulls as much as possible, and then it comes back, making a propeller motion.
Plus, there are other factors. The body has to be streamlined in order to get through water less and push against it less. And little kicks are better than big ones! Plus, the head rolls in rhythm with the arms, coming up for air when the arm is down, and going down when the arm comes up (you know, to get out of the way!).
And a lot goes into diving, too! Certain feet have to push off, then the arms off the block, and then the body has to be streamlined too! And the hip has to be hinged in order to enter the least amount of water possible, so there's less resistance! Wow... you've got to be impressed with professional swimmers! And that's just swimming... hurdle jumpers can do some pretty impressive stuff as well. And all those other professional athletes! They can do some amazing stuff too!
Developments can happen over long spaces of time as well... meaning generations! People are healthier and stronger (can run faster and jump higher) than hundreds of years ago. This is due to better food and better exercise gear. But scientists believe that someday we'll hit our stopping point... and won't be able to get faster or jump higher or stronger, even throughout generations.
Swimming & Exercise
Everyone knows we have to exercise to get fit. But how come? The body is a machine... an amazing machine extremely well-put together! But, while it does fine on a day-to-day basis, training can make it work better. The different components will work together smoother, and the muscles themselves will get stronger.
Also, healthy eating will increase the muscles' strength and efficiency. Why? Muscle make energy from oxygen and glucose... which explains why the heart beats faster during exercise time (to transport these items more quickly). But exercise can help make longer-lasting energy supplies, and if the lung muscles are strengthened, they can expand to take even more air (and therefore, oxygen) when needed!
Back to the "machine" part. The body parts can work together in many different ways, and those ways can sometimes be complicated. Take swimming, for example! Our feet can act as flippers... but that starts with an action from higher up our leg! And the hips roll in response to the movement of our arms! And even the propelling motion of our arms are controlled by two different muscles... the deltoid (sp?) shoulder-muscle and one in our arm! The muscle pulls as much as possible, and then it comes back, making a propeller motion.
Plus, there are other factors. The body has to be streamlined in order to get through water less and push against it less. And little kicks are better than big ones! Plus, the head rolls in rhythm with the arms, coming up for air when the arm is down, and going down when the arm comes up (you know, to get out of the way!).
And a lot goes into diving, too! Certain feet have to push off, then the arms off the block, and then the body has to be streamlined too! And the hip has to be hinged in order to enter the least amount of water possible, so there's less resistance! Wow... you've got to be impressed with professional swimmers! And that's just swimming... hurdle jumpers can do some pretty impressive stuff as well. And all those other professional athletes! They can do some amazing stuff too!
Developments can happen over long spaces of time as well... meaning generations! People are healthier and stronger (can run faster and jump higher) than hundreds of years ago. This is due to better food and better exercise gear. But scientists believe that someday we'll hit our stopping point... and won't be able to get faster or jump higher or stronger, even throughout generations.
Friday, December 21, 2012
Medical Central: Skin, Nails, & Hair... Oh My!
Today, we get to the surface of things... That's right! Today's subject is the Skin, which includes Nails and Hair.
Skin, Nails, and Hair
Now, it might surprise some of you to see these three things grouped together. Other than being on the surface of us, they don't seem like they have much in common. BEEP! Wrong! All these three things are made of a protein called keratin. And what we see is the dead part of the object. Now we covered some similarities, let's chop down to the more personalized parts.
Skin! We all know it. But did you know that it is an organ? The biggest organ in the body? And it can sure multitask! It keeps our body at a healthy temperature of around 95.8 degrees Farenheit (sp?), keeps water out of our bodies (yep, it's waterproof!), keeps the water we have inside our bodies in, keeps dirt and germs out, keeps all our organs, bones, and stuff inside, allows us to feel, sends the brain messages on what we feel, protection... That's a ton of stuff!
And remember how I said it was big? An adult's skin, when laid out, could cover a bed! And such a big thing is heavy too... an average person's can be over ten pounds heavy! Whoa! And skin can change sizes... when you grow, it grows. When a woman gets pregnant, the tummy-area skin grows over the bump, and then shrinks again. When you gain weight or big muscles, the skin grows.
Skin comes in different colors. Why? It's because of a chemical skin makes call meratin (sp?). It's anti-sunburn protection. Skin may make Vitamin D from sunlight, but too much sunlight causes sunburns or even skin cancer! Part of the skin's natural protection is making this chemical, which darkens the skin. That's how you tan. Some people naturally have darker skin, and therefore, better protection, but they still have to be careful.
Skin is made of layers. The top is called the epidermis, and the next one down is called just the dermis. Then there's a fatty layer which cushions the skin and has a lot of blood vessels and stuff.
The skin has a lot of stuff for its multiple jobs. It grows hair, which is major in temperature control. It has tons of nerve endings, for its touching job. It has blood vessels and muscles (connected to hairs to help with jobs, since they have to stick up to catch and keep warm air [cold weather] and then flatten in warm weather). And there's sweat glands, which release sweat, which cools you down (since evaporation takes heat, and sweat-evaporation takes body heat-energy, which in turns cools us down since it's taking heat away). In other words... a lot of stuff!
Hair grows out of hair follicles. It's almost all over our bodies, and in a variety of sizes from so-tiny-need-magnifying-glass-to-see to the clearly-visible hairs on our heads. There are a few places where there's none... but only a few. Humans have thousands of hair follicles. And the base of different hair types is different per type of hair (for example, curly hair has a kidney-shaped base). Typically, healthy hair is thick and shiny.
Hair follicles are party responsible for zits (pimples)... inside the follicle is a gland that makes and releases subum (sp?), a chemical that's meant for cleaning hair. But when the gland does an overdose job, the follicle's pore is blocked, and nothing can get out. This includes the oil, and bacteria. This in turn makes a swelling (a red bump), which is then called a zit. These overdose jobs happen a lot in the teenage years, when the extra hormones bouncing around tells the gland to make even more of this oil.
Nails! The nail's job is protection from bumping (helps when you stub your toe!). It's also handy for other stuff, like scratching itches, opening envelopes, and prying stickers off surfaces. The Nail is hard, primarily because the top is dead. But there's a living nail base which produces the keratin. Why is this area pink? Because of the blood vessels inside and flowing to the nail base! There's also a flap of skin underneath for protection (the crescent, white part), and a fold of skin helps protect the nail base and root.
Since nail and hair bits that can be seen are dead, that means we can't see them. So it's the only things on our body we cut often. But if we don't, they'll keep growing longer and longer (and nails that grow super-long not only curl up, but look gross!). For some folks, hair and nail keeping are parts of their personalities. There's products for dying and making hair shiny, and coloring nails. Stuff like this has been made and used since Ancient Egyptian days! And millions of hair-and-nail products are sold today! Yikes!
Skin, Nails, and Hair
Now, it might surprise some of you to see these three things grouped together. Other than being on the surface of us, they don't seem like they have much in common. BEEP! Wrong! All these three things are made of a protein called keratin. And what we see is the dead part of the object. Now we covered some similarities, let's chop down to the more personalized parts.
Skin! We all know it. But did you know that it is an organ? The biggest organ in the body? And it can sure multitask! It keeps our body at a healthy temperature of around 95.8 degrees Farenheit (sp?), keeps water out of our bodies (yep, it's waterproof!), keeps the water we have inside our bodies in, keeps dirt and germs out, keeps all our organs, bones, and stuff inside, allows us to feel, sends the brain messages on what we feel, protection... That's a ton of stuff!
And remember how I said it was big? An adult's skin, when laid out, could cover a bed! And such a big thing is heavy too... an average person's can be over ten pounds heavy! Whoa! And skin can change sizes... when you grow, it grows. When a woman gets pregnant, the tummy-area skin grows over the bump, and then shrinks again. When you gain weight or big muscles, the skin grows.
Skin comes in different colors. Why? It's because of a chemical skin makes call meratin (sp?). It's anti-sunburn protection. Skin may make Vitamin D from sunlight, but too much sunlight causes sunburns or even skin cancer! Part of the skin's natural protection is making this chemical, which darkens the skin. That's how you tan. Some people naturally have darker skin, and therefore, better protection, but they still have to be careful.
Skin is made of layers. The top is called the epidermis, and the next one down is called just the dermis. Then there's a fatty layer which cushions the skin and has a lot of blood vessels and stuff.
The skin has a lot of stuff for its multiple jobs. It grows hair, which is major in temperature control. It has tons of nerve endings, for its touching job. It has blood vessels and muscles (connected to hairs to help with jobs, since they have to stick up to catch and keep warm air [cold weather] and then flatten in warm weather). And there's sweat glands, which release sweat, which cools you down (since evaporation takes heat, and sweat-evaporation takes body heat-energy, which in turns cools us down since it's taking heat away). In other words... a lot of stuff!
Hair grows out of hair follicles. It's almost all over our bodies, and in a variety of sizes from so-tiny-need-magnifying-glass-to-see to the clearly-visible hairs on our heads. There are a few places where there's none... but only a few. Humans have thousands of hair follicles. And the base of different hair types is different per type of hair (for example, curly hair has a kidney-shaped base). Typically, healthy hair is thick and shiny.
Hair follicles are party responsible for zits (pimples)... inside the follicle is a gland that makes and releases subum (sp?), a chemical that's meant for cleaning hair. But when the gland does an overdose job, the follicle's pore is blocked, and nothing can get out. This includes the oil, and bacteria. This in turn makes a swelling (a red bump), which is then called a zit. These overdose jobs happen a lot in the teenage years, when the extra hormones bouncing around tells the gland to make even more of this oil.
Nails! The nail's job is protection from bumping (helps when you stub your toe!). It's also handy for other stuff, like scratching itches, opening envelopes, and prying stickers off surfaces. The Nail is hard, primarily because the top is dead. But there's a living nail base which produces the keratin. Why is this area pink? Because of the blood vessels inside and flowing to the nail base! There's also a flap of skin underneath for protection (the crescent, white part), and a fold of skin helps protect the nail base and root.
Since nail and hair bits that can be seen are dead, that means we can't see them. So it's the only things on our body we cut often. But if we don't, they'll keep growing longer and longer (and nails that grow super-long not only curl up, but look gross!). For some folks, hair and nail keeping are parts of their personalities. There's products for dying and making hair shiny, and coloring nails. Stuff like this has been made and used since Ancient Egyptian days! And millions of hair-and-nail products are sold today! Yikes!
Monday, December 17, 2012
Medical Central: Muscles
Today's subject is literally connected to the Skeleton... Muscles!!!
Muscles
Like I said above, Muscles are connected to the Skeleton. This is because muscles are what move the Skeleton (and, therefore, the rest of us). They're connected by hard fibers called tendons (the biggest tendon in the body, the Archilles [sp?] tendon in our leg's back, feels like bone, but can bend if pushed hard enough). Tendons also help a weird fact about muscles... muscles that are a good (though reasonable) distance from their targets can still move them! For example? The Deltoid (sp?) muscles is responsible for a lot of shoulder movement, but is directly on the shoulder, but some shoulder movements are controlled by muscles in our back! Since tendons can be long and they "stretch" out from the muscles, it explains this phenonemon (sp?).
Did you think that we had a lot of bones in our Skeleton? Well, get this... there are more than 600 muscles in our body!!! And that's just the controllable skeletal muscles! In fact, there are so many muscles, they take up around 1/2 of our body weight! Yikes! But they do many jobs... some muscles even protect abdonminable (sp?; in abdomen) organs that are in the abdomenal (sp?) cavity. And some of these jobs have different amounts of muscles doing it... making faces can take a lot of muscles! At least 11, but then the numbers can do a good amount of jumping from low to high and back again!
Despite having many jobs, muscles can be divided into three categories... skeletal muscles (the ones we can control), the smooth or involuntary muscles (the ones controlled without us thinking about it; also looks like strings with pointy ends while skeletal apparently have stripes), and the cardiac muscles (AKA, heart muscles). And there's an exception or two... lungs can be controlled by thought, but most of the time, the brain controls it. And sometimes there's not... certain organs controlled by smooth muscles keep on keeping on without any help from our thoughts, and the cardiac muscle keeps its beat no matter what, without rest or a break.
But no matter what, muscles are controlled by our brain in some degree. Smooth (or involuntary) muscles and cardiac muscles are controlled by the brain constantly. And even if we control the movements or actions, it requires the brain to send messages down the nerves in our spine, out the nerve endings, into the muscles, and then the muscles reacting. That may sound long, but flex your finger or roll your eyes. That whole process just happened! Probably even a few times! But it happened in less than a second. Yikes once again!
There are some muscles that will surprise you. You know about the colored ring around the pupil of our eyes. Get this: it's a smooth muscle! The brain is in total control of that one... we have no-go on it! And the esophagus also has a muscles all around its wall that does a lot of pushing after we swallow (in order to get it to our smooth-muscled stomach).
Muscles work by contracting. Muscles are made up of muscle fibers, which are made of even smaller fibers, which are then made of two other kinds of fibers! When they get the signal to work, these two types of fibers pull and get together, making the muscle contract. When the muscle relaxes, they ease off each other (though they stay pretty close to each other).
The relaxing part may have confused you a little. But when the muscles stretches out, they relax. But muscles only pull... never push. So how do they stretch out? Muscles work in pairs! When it's time to stretch, the other set of muscles is contacted, and it pulls. That makes the part of the body move the other way, and the other muscle relaxes. Take the arm for example... when you bend it up, the front of your arm's muscle pulls. When you bend it down, the muscle in the back of your arm pulls on the elbow's end, and the arm's front muscle that was pulling before relaxes and stretches out.
Muscles, of course, need energy. Everyone knows this. Where does it get energy? You know the answer... from the food we eat, and from the air we breathe, of course! Muscles need energy from food and oxygen to go. The energy made is stored in a chemical called ATP in our cells. However, when we are working really hard, this energy can be used up. And while the muscles can make energy without ATPs for a while, it doesn't last long. This process makes lactic acid, and, like any of your would expect from something called "acid", it hurts our muscles! That's when the body screams at us, "STOP! IT'S TIME FOR A BREAK!!! YOU NEED TO REST, RECOVER, AND GET SOME EXTRA OXYGEN!" Of course, you would already be breathing harder and faster at this point to get that extra oxygen, but it's not really helping at this point. That's usually why athletes need rest after their sport... sprinters, who really push it, for example!
Muscles
Like I said above, Muscles are connected to the Skeleton. This is because muscles are what move the Skeleton (and, therefore, the rest of us). They're connected by hard fibers called tendons (the biggest tendon in the body, the Archilles [sp?] tendon in our leg's back, feels like bone, but can bend if pushed hard enough). Tendons also help a weird fact about muscles... muscles that are a good (though reasonable) distance from their targets can still move them! For example? The Deltoid (sp?) muscles is responsible for a lot of shoulder movement, but is directly on the shoulder, but some shoulder movements are controlled by muscles in our back! Since tendons can be long and they "stretch" out from the muscles, it explains this phenonemon (sp?).
Did you think that we had a lot of bones in our Skeleton? Well, get this... there are more than 600 muscles in our body!!! And that's just the controllable skeletal muscles! In fact, there are so many muscles, they take up around 1/2 of our body weight! Yikes! But they do many jobs... some muscles even protect abdonminable (sp?; in abdomen) organs that are in the abdomenal (sp?) cavity. And some of these jobs have different amounts of muscles doing it... making faces can take a lot of muscles! At least 11, but then the numbers can do a good amount of jumping from low to high and back again!
Despite having many jobs, muscles can be divided into three categories... skeletal muscles (the ones we can control), the smooth or involuntary muscles (the ones controlled without us thinking about it; also looks like strings with pointy ends while skeletal apparently have stripes), and the cardiac muscles (AKA, heart muscles). And there's an exception or two... lungs can be controlled by thought, but most of the time, the brain controls it. And sometimes there's not... certain organs controlled by smooth muscles keep on keeping on without any help from our thoughts, and the cardiac muscle keeps its beat no matter what, without rest or a break.
But no matter what, muscles are controlled by our brain in some degree. Smooth (or involuntary) muscles and cardiac muscles are controlled by the brain constantly. And even if we control the movements or actions, it requires the brain to send messages down the nerves in our spine, out the nerve endings, into the muscles, and then the muscles reacting. That may sound long, but flex your finger or roll your eyes. That whole process just happened! Probably even a few times! But it happened in less than a second. Yikes once again!
There are some muscles that will surprise you. You know about the colored ring around the pupil of our eyes. Get this: it's a smooth muscle! The brain is in total control of that one... we have no-go on it! And the esophagus also has a muscles all around its wall that does a lot of pushing after we swallow (in order to get it to our smooth-muscled stomach).
Muscles work by contracting. Muscles are made up of muscle fibers, which are made of even smaller fibers, which are then made of two other kinds of fibers! When they get the signal to work, these two types of fibers pull and get together, making the muscle contract. When the muscle relaxes, they ease off each other (though they stay pretty close to each other).
The relaxing part may have confused you a little. But when the muscles stretches out, they relax. But muscles only pull... never push. So how do they stretch out? Muscles work in pairs! When it's time to stretch, the other set of muscles is contacted, and it pulls. That makes the part of the body move the other way, and the other muscle relaxes. Take the arm for example... when you bend it up, the front of your arm's muscle pulls. When you bend it down, the muscle in the back of your arm pulls on the elbow's end, and the arm's front muscle that was pulling before relaxes and stretches out.
Muscles, of course, need energy. Everyone knows this. Where does it get energy? You know the answer... from the food we eat, and from the air we breathe, of course! Muscles need energy from food and oxygen to go. The energy made is stored in a chemical called ATP in our cells. However, when we are working really hard, this energy can be used up. And while the muscles can make energy without ATPs for a while, it doesn't last long. This process makes lactic acid, and, like any of your would expect from something called "acid", it hurts our muscles! That's when the body screams at us, "STOP! IT'S TIME FOR A BREAK!!! YOU NEED TO REST, RECOVER, AND GET SOME EXTRA OXYGEN!" Of course, you would already be breathing harder and faster at this point to get that extra oxygen, but it's not really helping at this point. That's usually why athletes need rest after their sport... sprinters, who really push it, for example!
Sunday, December 16, 2012
Medical Central: The Skeleton
I read more on the Human Body. This time, the body's primary structure was explored... the Skeleton!
Skeleton
What supports our body, and lets it keep our shape? We pretty much all know the answer... the Skeleton! The Skeleton is our support made of bone. Without it... we'd only be 3/4 of our weight with the Skeleton (since the Skeleton takes up 1/4 of our weight), but we'd also be a goopy (sp?) mass on the floor, and probably wouldn't function well, because the Skeleton supports our organs as well.
But here's some interesting data! The Skeleton takes up 1/4 of our weight! On average, an adult has around 206 bones, though when we're babies, we can have more than 300 bones! Wow! How come this number changes? Well, as we grow, so do our bones. They grow longer and stronger, and some even fuse together!
Just like there are a ton of bones in the body, there are also a bunch of bone types. We all know about the spine. It is made up of 24 vertebrae, of which 7 are in the neck, and there's a primary one that connects to the pelvic (hip) bone. Between each vertebrae is a cartilage (rubbery-like tough substance) disk that absorb shock. We also know of ribs, which protect organs like the heart and lungs. But did you know about the breastbone, which is the ribs' anchor?
And there are a ton of other types... all with different jobs! Their strengths differ too... leg bones, since they hold us up, are the strongest in the body. They are also the longest... the upper bone leg, the femur, is the longest bone in our body! And there are different amounts of bones per job... our lower legs and arms have a double-set of bones, though the lower leg has one bigger bone than the other. And there are some joints that have a whole bunch of bones, like the foot joint, which has 7. And our palm has 5 bones! Talk about more than you would think!
And the bones are sometimes different for each gender. Take the pelvic bone. It supports our abdonmin's (sp?) organs, but there's still a large opening in it. The opening (and the pelvic bone itself) is bigger in females. Why? It's because women give birth to babies! The babies need more room in order to exit the woman's body. So the opening in the pelvic bone is bigger in females than in males.
Bones are hard and sturdy. Why? They're made of calcium, which is a mineral. There are a few other minerals, but calcium's the primary, and most well-known. The calcium comes from blood vessels called oestroplasts (sp?). But we need to help them by getting calcium-rich foods, like certain veggies, into our bodies!
Skeleton
What supports our body, and lets it keep our shape? We pretty much all know the answer... the Skeleton! The Skeleton is our support made of bone. Without it... we'd only be 3/4 of our weight with the Skeleton (since the Skeleton takes up 1/4 of our weight), but we'd also be a goopy (sp?) mass on the floor, and probably wouldn't function well, because the Skeleton supports our organs as well.
But here's some interesting data! The Skeleton takes up 1/4 of our weight! On average, an adult has around 206 bones, though when we're babies, we can have more than 300 bones! Wow! How come this number changes? Well, as we grow, so do our bones. They grow longer and stronger, and some even fuse together!
Just like there are a ton of bones in the body, there are also a bunch of bone types. We all know about the spine. It is made up of 24 vertebrae, of which 7 are in the neck, and there's a primary one that connects to the pelvic (hip) bone. Between each vertebrae is a cartilage (rubbery-like tough substance) disk that absorb shock. We also know of ribs, which protect organs like the heart and lungs. But did you know about the breastbone, which is the ribs' anchor?
And there are a ton of other types... all with different jobs! Their strengths differ too... leg bones, since they hold us up, are the strongest in the body. They are also the longest... the upper bone leg, the femur, is the longest bone in our body! And there are different amounts of bones per job... our lower legs and arms have a double-set of bones, though the lower leg has one bigger bone than the other. And there are some joints that have a whole bunch of bones, like the foot joint, which has 7. And our palm has 5 bones! Talk about more than you would think!
And the bones are sometimes different for each gender. Take the pelvic bone. It supports our abdonmin's (sp?) organs, but there's still a large opening in it. The opening (and the pelvic bone itself) is bigger in females. Why? It's because women give birth to babies! The babies need more room in order to exit the woman's body. So the opening in the pelvic bone is bigger in females than in males.
Bones are hard and sturdy. Why? They're made of calcium, which is a mineral. There are a few other minerals, but calcium's the primary, and most well-known. The calcium comes from blood vessels called oestroplasts (sp?). But we need to help them by getting calcium-rich foods, like certain veggies, into our bodies!
Saturday, December 15, 2012
Medical Central: The Human Body: Cells, Age, and Replacement Tech
Today, read some on the human body, and some of tech that is used (and being trialed and tested) for replacing damaged and not-so-good body parts.
Human Body: Cells, Age, and Replacement Tech
We all know that life is made of cells. Some of us may know that some forms of life, like the bacteria, are made of only one cell. That's the total opposite of human bodies, which have around 10 trillion cells. Yikes! But here's an interesting fact... we all start out life as one cell. Then we grow, and the cells go through mitosis (cell separation) with a special structure inside the body.
The cells aren't all the same... not at all! Cells come in all sorts of different shapes and sizes and functions. Nerve cells have an axon and dendrites which are used to receive and send signals respectively. Smooth muscle cells, which control involuntary muscles and organs (example: stomach), look different and have to "tails" or "tentacles". Sperm cells (an only-male cell) have a tail for swimming around, but they look different and have a different purpose: finding and fertializing (sp?) a female egg cell!
While cells, the basic building materials of life, are different, there are similarities. Cells all have certain structures (and a lot of them) that help them to live. There's one that supplies energy for the cell, some help clear the area of debris, and some help in the mitosis process. The nucleus holds the chromosomes, and the very center of the nucleus controls a lot of it.
There are two main types of chromosomes: the X and the Y chromosome. While both male and females have the X chromosome, only the females double on the X chromosome, while males have a single Y and a single X chromosome. Chromosomes hold DNA. No matter what cell it is, each cells has a basic copy of DNA that's pretty much the same. And each DNA pattern (kind of like the body's plan) is unique and special to each person.
We all know that different ages means different heights, strengths, and so on. There are even certain actions and abilities that are called "milestones" that help keep track of stuff. Telling age can be pretty easy sometimes... the rate of maturity, what one can do, and even the area around the eyes can tell age! But becoming an adult (after puberty) is usually done by age 20. Cells grow and multiply still, but, unlike past years, they're not for growing... they're for replacing the deal cells that show up. And while excersising (sp?) and healthy living and stuff can improve strength and stuff, no one really grows taller after they are 20.
In fact, many old-age problems come from cells not multiplying as much as they used to... Loss of strength comes from less muscle cells, and the famous memory problems come from loss of brain cells.
Now, leaving the cells arena, we come to technology. We covered Medical Imaging for a long while on this blog, and here's some data on some different Medical tech. We know that certain devices can totally replace body parts... some of the most famous are the robotic (and sometimes just artificial) arms and legs. Some of you know pacemakers, which help the heart keep to a beat. And some of you even know about the other-famous hip replacements (total ones include the ball-and-socket joint).
But there are plenty others. Other joints can have replacements... finger, toe, elbow, and knee joints are examples listed in the book. Some replacements are from other humans, like the well-known kidney replacement. But did you know that corneas can be transferred over and replaced too? And hearts can be transferred over from just-dead people (Repeat: JUST dead, not long-time dead!). And skin grafts, while some are man-made (not with natural stuff), are able to come from the same person!
There are even more radical replacements! There are devices to replace damaged brain cells, not-working inner ears (including electrical translator which sends signals into the brain to let it figure out the sound), artificial hearts (apparently being trialed on humans), and there's even an artificial lung being developed for those with diseased and damaged parts of air-filled areas of the body! And even the well-known robotic arm is jumping up in tech a little... some robo-arms have hands that move (at least the fingers)!
But some tech used for helping is old-fashioned, and has been used as long as anyone can remember... for walking, there's a very famous one. It stills exists in the real world, and not just movies and books. It's the good old walking stick! Hey... it pays to stick with what works sometimes, and it's cool that it's still around, despite all the high-tech solutions out there!
Human Body: Cells, Age, and Replacement Tech
We all know that life is made of cells. Some of us may know that some forms of life, like the bacteria, are made of only one cell. That's the total opposite of human bodies, which have around 10 trillion cells. Yikes! But here's an interesting fact... we all start out life as one cell. Then we grow, and the cells go through mitosis (cell separation) with a special structure inside the body.
The cells aren't all the same... not at all! Cells come in all sorts of different shapes and sizes and functions. Nerve cells have an axon and dendrites which are used to receive and send signals respectively. Smooth muscle cells, which control involuntary muscles and organs (example: stomach), look different and have to "tails" or "tentacles". Sperm cells (an only-male cell) have a tail for swimming around, but they look different and have a different purpose: finding and fertializing (sp?) a female egg cell!
While cells, the basic building materials of life, are different, there are similarities. Cells all have certain structures (and a lot of them) that help them to live. There's one that supplies energy for the cell, some help clear the area of debris, and some help in the mitosis process. The nucleus holds the chromosomes, and the very center of the nucleus controls a lot of it.
There are two main types of chromosomes: the X and the Y chromosome. While both male and females have the X chromosome, only the females double on the X chromosome, while males have a single Y and a single X chromosome. Chromosomes hold DNA. No matter what cell it is, each cells has a basic copy of DNA that's pretty much the same. And each DNA pattern (kind of like the body's plan) is unique and special to each person.
We all know that different ages means different heights, strengths, and so on. There are even certain actions and abilities that are called "milestones" that help keep track of stuff. Telling age can be pretty easy sometimes... the rate of maturity, what one can do, and even the area around the eyes can tell age! But becoming an adult (after puberty) is usually done by age 20. Cells grow and multiply still, but, unlike past years, they're not for growing... they're for replacing the deal cells that show up. And while excersising (sp?) and healthy living and stuff can improve strength and stuff, no one really grows taller after they are 20.
In fact, many old-age problems come from cells not multiplying as much as they used to... Loss of strength comes from less muscle cells, and the famous memory problems come from loss of brain cells.
Now, leaving the cells arena, we come to technology. We covered Medical Imaging for a long while on this blog, and here's some data on some different Medical tech. We know that certain devices can totally replace body parts... some of the most famous are the robotic (and sometimes just artificial) arms and legs. Some of you know pacemakers, which help the heart keep to a beat. And some of you even know about the other-famous hip replacements (total ones include the ball-and-socket joint).
But there are plenty others. Other joints can have replacements... finger, toe, elbow, and knee joints are examples listed in the book. Some replacements are from other humans, like the well-known kidney replacement. But did you know that corneas can be transferred over and replaced too? And hearts can be transferred over from just-dead people (Repeat: JUST dead, not long-time dead!). And skin grafts, while some are man-made (not with natural stuff), are able to come from the same person!
There are even more radical replacements! There are devices to replace damaged brain cells, not-working inner ears (including electrical translator which sends signals into the brain to let it figure out the sound), artificial hearts (apparently being trialed on humans), and there's even an artificial lung being developed for those with diseased and damaged parts of air-filled areas of the body! And even the well-known robotic arm is jumping up in tech a little... some robo-arms have hands that move (at least the fingers)!
But some tech used for helping is old-fashioned, and has been used as long as anyone can remember... for walking, there's a very famous one. It stills exists in the real world, and not just movies and books. It's the good old walking stick! Hey... it pays to stick with what works sometimes, and it's cool that it's still around, despite all the high-tech solutions out there!
Friday, December 14, 2012
Medical Central: The Possible Future Of Medical Imaging
I read more on Medical Imaging. We covered an interesting concept: the possible future of Medical Imaging!
The Possible Future of Medical Imaging
The science of Medical Imaging has been going at a fast rate... and getting much (extremely) faster with developments in technology and the Medical Imaging ways! It started off with X-Rays, and has boomed significantly. It may be possible that soon we'll be using scanners and devices that we see only in sci-fi movies! Devices include extremely tiny robots that can either be endoscopes or surgery-doing devices, VR goggles that can help surgeons in the surgery room, handheld scanners that can see inside the body, and the book even suggests a magnetic device to shut down the pain centers of the brain for a short bit!
Already, advanced imaging is going up. Scientists are working on a way called HUTT, which is an advanced version of Ultrasound, which should even figure out different tissues by just figuring out how the sound changes when it hits stuff in the body! They're even working on better X-Rays... double detectors should be better than single-detectors, and make better images with less X-Rays (according to the book). And open-sided MRI Scanners are already in use, as mentioned in the last post. And work is being done to figure out how to make cheaper and smaller MRI Scanners. There's a device out now that may be the trick, and is smaller and cheaper.
They are also working on a way called "optical imaging" in the book, which is similar to Ultrasound and HUTT... except it uses a long electromagnetic wave called infrared light to see inside the body! It can tell different tissues apart the same way HUTT does (except with infrared light). Optical Imaging is actually good for babies, because they're too jumpy to go through and MRI, and are way too sensitive to X-Rays.
Scientists are also working on a device called TMS. TMS uses magnetic waves to stimulate or "turn off" parts of the brain. Scientists think that this can be used to take care of depression. It may also possibly be the thing that will be used in the future as a pain-reliever that's safe, since it may shut down the brain's areas that deal with pain. It can be used to map out the brain, since stimulates areas, and scientists can map out that stimulation (according to book). fMRI and another method is used to check this thing and its effects out.
It may be possible that Medical Imaging jumps up so much, that it may be able to read a person's thoughts! This would be done to seeing certain patterns in the brain, and figuring out what these patterns mean, figuring out the person's thoughts! Some scientists fight against this, though. Why? Apparently, even when two patients are thinking about similar things, their brains will do different signal-patterns!
The Possible Future of Medical Imaging
The science of Medical Imaging has been going at a fast rate... and getting much (extremely) faster with developments in technology and the Medical Imaging ways! It started off with X-Rays, and has boomed significantly. It may be possible that soon we'll be using scanners and devices that we see only in sci-fi movies! Devices include extremely tiny robots that can either be endoscopes or surgery-doing devices, VR goggles that can help surgeons in the surgery room, handheld scanners that can see inside the body, and the book even suggests a magnetic device to shut down the pain centers of the brain for a short bit!
Already, advanced imaging is going up. Scientists are working on a way called HUTT, which is an advanced version of Ultrasound, which should even figure out different tissues by just figuring out how the sound changes when it hits stuff in the body! They're even working on better X-Rays... double detectors should be better than single-detectors, and make better images with less X-Rays (according to the book). And open-sided MRI Scanners are already in use, as mentioned in the last post. And work is being done to figure out how to make cheaper and smaller MRI Scanners. There's a device out now that may be the trick, and is smaller and cheaper.
They are also working on a way called "optical imaging" in the book, which is similar to Ultrasound and HUTT... except it uses a long electromagnetic wave called infrared light to see inside the body! It can tell different tissues apart the same way HUTT does (except with infrared light). Optical Imaging is actually good for babies, because they're too jumpy to go through and MRI, and are way too sensitive to X-Rays.
Scientists are also working on a device called TMS. TMS uses magnetic waves to stimulate or "turn off" parts of the brain. Scientists think that this can be used to take care of depression. It may also possibly be the thing that will be used in the future as a pain-reliever that's safe, since it may shut down the brain's areas that deal with pain. It can be used to map out the brain, since stimulates areas, and scientists can map out that stimulation (according to book). fMRI and another method is used to check this thing and its effects out.
It may be possible that Medical Imaging jumps up so much, that it may be able to read a person's thoughts! This would be done to seeing certain patterns in the brain, and figuring out what these patterns mean, figuring out the person's thoughts! Some scientists fight against this, though. Why? Apparently, even when two patients are thinking about similar things, their brains will do different signal-patterns!
Thursday, December 13, 2012
Medical Central: Medical Imaging--For Other Stuff Too!
Read more on Medical Imaging today, and got some more details on something that has been mentioned before: Medical Imaging can be used for surgery too!
Medical Imaging--Other Uses
Now, some us know that radiation has been used to kill and battle cancers. Radiation kills dividing cells... that's bad for us humans, who have dividing cells. But it's even worse for cancers and their tumors... why? Tumors are made up of very rapidly dividing cells... faster than normal human cells! So a burst of radiation can do more damage to a cancer's tumor than our cells. But you still have to be careful... even these small bursts can have side-effects like the famous hair loss, and even nausea according to the book. And those bursts can still affect other tissues. It can be a tricky problem.
Then comes in Medical Imaging! MRI scans and other scans, like PET, CT, and fMRI, can pinpoint these tumors better. With a better location, the radiation treatment can focus the gamma or X-Rays more onto the tumor and not other tissues... and with less radiation! Talk about safer!
It has been said that endoscopes and some other Medical Imaging techniques can be used in keyhole surgeries. This is not the only way Medical Imaging can be used for surgery. Scans can be made of, say... a patient's brain. This can help the surgeon even before the surgery. But sometimes tissues in the brain and other areas move a bit, so the surgeon needs a little more help. Here comes in a special MRI scanner called an open-side MRI. There's an open area in, where else, the side, where the surgeon can scan. Since it's an MRI, the surgeon needs to use special tools for surgery that are non-magnetic. The MRI scans the brain constantly, and the computer makes and aligns the image as needed, and then feeds the image to a TV screen that's where the surgeon can see it. This helps the surgeon keep track of everything and accomplish the surgery.
The MRI can be mixed with different things, like PET, CT, and fMRI. This helps the surgeon by seeing other things, like different tissues and blood streams (book says major ones). This helps so that the surgeon doesn't damage anything else, even by accident. When working in a major area of the brain, like the movement-controlling and speech controlling areas, this is important, because a mistake can leave a patient paralyzed or speechless for life!
This type of surgery has been primarily used for brain surgery. Studies are being made, however. Maybe one day, they'll be able to do tricky & complicated surgeries in areas like the kidneys and other places!
MRI has been discovered to have a different treatment ability too. MRI creates electrical and magnetic fields. Scientists have discovered that patients suffering from depression that go through MRI scans come out happier because of these fields! No one really knows why, however. But this was a good discovery, however! But MRI Scanners are very expensive. So scientists are making animal tests with a smaller device that makes similar fields (according to the book). They're hoping that this device can eventually be used for a treatment for depression! That's amazing!
Medical Imaging--Other Uses
Now, some us know that radiation has been used to kill and battle cancers. Radiation kills dividing cells... that's bad for us humans, who have dividing cells. But it's even worse for cancers and their tumors... why? Tumors are made up of very rapidly dividing cells... faster than normal human cells! So a burst of radiation can do more damage to a cancer's tumor than our cells. But you still have to be careful... even these small bursts can have side-effects like the famous hair loss, and even nausea according to the book. And those bursts can still affect other tissues. It can be a tricky problem.
Then comes in Medical Imaging! MRI scans and other scans, like PET, CT, and fMRI, can pinpoint these tumors better. With a better location, the radiation treatment can focus the gamma or X-Rays more onto the tumor and not other tissues... and with less radiation! Talk about safer!
It has been said that endoscopes and some other Medical Imaging techniques can be used in keyhole surgeries. This is not the only way Medical Imaging can be used for surgery. Scans can be made of, say... a patient's brain. This can help the surgeon even before the surgery. But sometimes tissues in the brain and other areas move a bit, so the surgeon needs a little more help. Here comes in a special MRI scanner called an open-side MRI. There's an open area in, where else, the side, where the surgeon can scan. Since it's an MRI, the surgeon needs to use special tools for surgery that are non-magnetic. The MRI scans the brain constantly, and the computer makes and aligns the image as needed, and then feeds the image to a TV screen that's where the surgeon can see it. This helps the surgeon keep track of everything and accomplish the surgery.
The MRI can be mixed with different things, like PET, CT, and fMRI. This helps the surgeon by seeing other things, like different tissues and blood streams (book says major ones). This helps so that the surgeon doesn't damage anything else, even by accident. When working in a major area of the brain, like the movement-controlling and speech controlling areas, this is important, because a mistake can leave a patient paralyzed or speechless for life!
This type of surgery has been primarily used for brain surgery. Studies are being made, however. Maybe one day, they'll be able to do tricky & complicated surgeries in areas like the kidneys and other places!
MRI has been discovered to have a different treatment ability too. MRI creates electrical and magnetic fields. Scientists have discovered that patients suffering from depression that go through MRI scans come out happier because of these fields! No one really knows why, however. But this was a good discovery, however! But MRI Scanners are very expensive. So scientists are making animal tests with a smaller device that makes similar fields (according to the book). They're hoping that this device can eventually be used for a treatment for depression! That's amazing!
Sunday, December 9, 2012
Medical Central: Combining Stuff!
Read more on Medical Imaging today. We covered something interesting... combining the multiple Medical Imaging ways!
Combining Stuff
We've covered a lot of ways that are used in Medical Imaging. PET, CT, MRI... to name a few. Each of these have really good points... but some have very bad points. PET and CT use radiation, which can be dangerous in over-dosages, and can't ever be used on a pregnant woman. Endoscopes and Ultrasound have different image-quality, image area size, and expense cost for these images. And each of these can see different things... one sees how the body uses stuff, but not structure... another sees this structure... and yet another actually sees these things, not just scan and construct the image! And MRI can cause clastrophobia (sp?), AKA a fear of small and enclosed places. While ways have been made to try and fix these (like an "open" MRI to ease up the clastrophobia [sp?]), there are still some problems to go with the ups.
Scientists, of course, have figured out something cooking figured out ages ago... combining things can make a one big good thing! They have started combining different Medical Imaging ways to see things better and differently. One way is in brain imaging, where PET has been combined with a different scanning technique to see how the brain works... by both seeing structure and how the body uses its systems. While the brain-imaging is mainly used in research, it has been used to figure out some abnormal brain activity for some patients with brain-problems (increasingly, according to the book).
Combining PET with CT helps pick up how well drugs are working. Scientists had been using PET to check for drug-effects on animals for a while, but now are using a combo in order to check on how some drugs effect humans. Take Alheizmer's (sp?) disease, which affects the brain especially in later years. It causes clogging of a substance called alyhmoid (sp?). Scientists have figured out that a certain substance that can be radioactively tagged sticks onto alyhmoid. They use this tagged substance to check to see how certain drugs effect the disease.
Combining Medical Imaging ways have some problems. The brain imaging mentioned above, for example, can't keep up with the constantly changing signals in the brain. The brain can change signals in milliseconds... talk about fast! But that's too fast for a machine to keep up sometimes. But scientists are even figuring out these problems, since combing Medical Imaging ways are great in research and diagnosing problems (according to the book). They combined a method called EEGs (which uses electrodes [electricity conductors] to see how signals work in the brain and keep up with them in the brain according to the book) and MEGs (which does same thing as EEGs, just with magnetism, according to the book) with a different scanning method. Using this, they can keep track of the brain's signals, and see which parts of the brain are active certain things are being done!
But that's just an example... combining different things and Medical Imaging ways even helps keep an eye on structure while seeing which parts of the brain are active or not! That's just plain cool! And that's just for the brain... there are many possiblities (sp?) for combining Medical Imaging ways, and how they help people and doctors (combining Medical Imaging ways can help spot tumors as early as possible too)! And more research is being made too!
Combining Stuff
We've covered a lot of ways that are used in Medical Imaging. PET, CT, MRI... to name a few. Each of these have really good points... but some have very bad points. PET and CT use radiation, which can be dangerous in over-dosages, and can't ever be used on a pregnant woman. Endoscopes and Ultrasound have different image-quality, image area size, and expense cost for these images. And each of these can see different things... one sees how the body uses stuff, but not structure... another sees this structure... and yet another actually sees these things, not just scan and construct the image! And MRI can cause clastrophobia (sp?), AKA a fear of small and enclosed places. While ways have been made to try and fix these (like an "open" MRI to ease up the clastrophobia [sp?]), there are still some problems to go with the ups.
Scientists, of course, have figured out something cooking figured out ages ago... combining things can make a one big good thing! They have started combining different Medical Imaging ways to see things better and differently. One way is in brain imaging, where PET has been combined with a different scanning technique to see how the brain works... by both seeing structure and how the body uses its systems. While the brain-imaging is mainly used in research, it has been used to figure out some abnormal brain activity for some patients with brain-problems (increasingly, according to the book).
Combining PET with CT helps pick up how well drugs are working. Scientists had been using PET to check for drug-effects on animals for a while, but now are using a combo in order to check on how some drugs effect humans. Take Alheizmer's (sp?) disease, which affects the brain especially in later years. It causes clogging of a substance called alyhmoid (sp?). Scientists have figured out that a certain substance that can be radioactively tagged sticks onto alyhmoid. They use this tagged substance to check to see how certain drugs effect the disease.
Combining Medical Imaging ways have some problems. The brain imaging mentioned above, for example, can't keep up with the constantly changing signals in the brain. The brain can change signals in milliseconds... talk about fast! But that's too fast for a machine to keep up sometimes. But scientists are even figuring out these problems, since combing Medical Imaging ways are great in research and diagnosing problems (according to the book). They combined a method called EEGs (which uses electrodes [electricity conductors] to see how signals work in the brain and keep up with them in the brain according to the book) and MEGs (which does same thing as EEGs, just with magnetism, according to the book) with a different scanning method. Using this, they can keep track of the brain's signals, and see which parts of the brain are active certain things are being done!
But that's just an example... combining different things and Medical Imaging ways even helps keep an eye on structure while seeing which parts of the brain are active or not! That's just plain cool! And that's just for the brain... there are many possiblities (sp?) for combining Medical Imaging ways, and how they help people and doctors (combining Medical Imaging ways can help spot tumors as early as possible too)! And more research is being made too!
Friday, December 7, 2012
Medical Central: Endoscopes
Read more on Medical Imaging today. We leave the world of using waves, radioactivity, and other indirect methods (according to book) to look at a more direct method... endoscopes!
Endoscopes
Endoscopes are little cameras on the end of long, flexible tubes. The tubes are glass optical fibers, which have multiple uses, like the Internet or TV or phones, or (the book says) other media sources. But the book says that these things were made originally for medical purposes.
Tubes to see inside the body were developed somewhere in the 19th Century, according to the book. But it was only when the electrical light was made was this invention start going up in popularity, usuage (sp?), and usefulness. Even then, it took a little bit for the flexible tubes, not stiff ones, to come out. And then came the less-than-millimeter-thick ones!
Endoscopes work by using light pulses. There's a light source in the tube (outside the body which is transmitted through the tube, according to book), and the lens does the usual job of focusing. A TV gets the signals and broadcasts the images. Endoscopes are named after their job... like, gastroscopes go down the throat and check out the esogophus and stomach areas.
Endoscopes can look at many things... even ultrathin needlescopes exist which can check inside of blood vessels! How do they look inside? They can be inserted through openings... which include natural ones like the nose, mouth, or rectum, and artificial ones (according to book). The mouth can be a multi-use... both to check the stomach (which multiple wrinkles help it stretch out to receive food) and the lungs area according to the book. This can help check and diagnose different problems, like lung-heart sticking, tumors (of course), ulcers (book says sores in stomach), and even swelling in different areas (like bronchial tubes according to book).
But, despite this, endoscopes have a blind spot... the small intestine. To fix this problem, a different kind of endoscope was developed by Professor Paul Swain of the London Hospital: the "camera in a pill" (formal name: wireless capsule endoscope, according to the book). This camera is barely larger than the average pill. It can travel down the digestive system, and take pictures. Modern developments allow doctors to be able to stop the pill where they need to, because they're more like mini-robots and have things to attach themselves to the walls. But these cameras are small, and send the signals to a receiver, which the book says the patient wears.
Endoscopes
Endoscopes are little cameras on the end of long, flexible tubes. The tubes are glass optical fibers, which have multiple uses, like the Internet or TV or phones, or (the book says) other media sources. But the book says that these things were made originally for medical purposes.
Tubes to see inside the body were developed somewhere in the 19th Century, according to the book. But it was only when the electrical light was made was this invention start going up in popularity, usuage (sp?), and usefulness. Even then, it took a little bit for the flexible tubes, not stiff ones, to come out. And then came the less-than-millimeter-thick ones!
Endoscopes work by using light pulses. There's a light source in the tube (outside the body which is transmitted through the tube, according to book), and the lens does the usual job of focusing. A TV gets the signals and broadcasts the images. Endoscopes are named after their job... like, gastroscopes go down the throat and check out the esogophus and stomach areas.
Endoscopes can look at many things... even ultrathin needlescopes exist which can check inside of blood vessels! How do they look inside? They can be inserted through openings... which include natural ones like the nose, mouth, or rectum, and artificial ones (according to book). The mouth can be a multi-use... both to check the stomach (which multiple wrinkles help it stretch out to receive food) and the lungs area according to the book. This can help check and diagnose different problems, like lung-heart sticking, tumors (of course), ulcers (book says sores in stomach), and even swelling in different areas (like bronchial tubes according to book).
But, despite this, endoscopes have a blind spot... the small intestine. To fix this problem, a different kind of endoscope was developed by Professor Paul Swain of the London Hospital: the "camera in a pill" (formal name: wireless capsule endoscope, according to the book). This camera is barely larger than the average pill. It can travel down the digestive system, and take pictures. Modern developments allow doctors to be able to stop the pill where they need to, because they're more like mini-robots and have things to attach themselves to the walls. But these cameras are small, and send the signals to a receiver, which the book says the patient wears.
Sunday, December 2, 2012
Medical Central: Different Medical Imaging Stuff
Read more on Medical Imaging. It covered some different stuff.
Different Medical Imaging Stuff
Lungs are hard to scan with MRI Scanners. Why? They're full of air, which can't react very well to the magnetic stuff. In the 1990's, a scientist figured out a way to fix this little problem. A patient breathes in a lungful of a certain gas... book says a special form of helium or xenon. This is highly reactive to MRI scans, about 100,000 times more so than water according to the book. The patient only holds it for the scans, which is about 10 seconds, according to the book. The book says that this technique is only in early research stages, and it not used in clinics or for medical purposes or by doctors.
Breast cancer is one of the most common forms of cancer caught by woman according to the book. Once women reach a certain age (50 years, according to the book) they're advised to start taking an annual test for breast cancer, according to the book. It's an X-Ray called a mammogram (a contrast medium used for detecting breast cancer is gadolinium according to the book). MRIs do a better job for "breast cancer screening" (according to book), but they're more expensive, and book says they take longer. And sometimes they give out false alarms (book calls it "false positives")... they say that breast cancer's there, but it's not really.
We covered that CT and MRI Scanner images are made by computers. They take a ton of data (information, according to book), and make an image. And then technologist or whoever is working on the thing can have fun with it. There's multiple ways of doing this. For one thing, the person can tell the computer to highlight certain areas and tissues with bright colors (according to book; one example used is tumors). And they can ignore certain areas... and can completely take them away from the image! That's what the book says, anyway. Each image can be especially fitted for what each patient needs and for even just the patient, according to the book. It's amazing how far computers have come, and how they're used even in just medical purposes!
Different Medical Imaging Stuff
Lungs are hard to scan with MRI Scanners. Why? They're full of air, which can't react very well to the magnetic stuff. In the 1990's, a scientist figured out a way to fix this little problem. A patient breathes in a lungful of a certain gas... book says a special form of helium or xenon. This is highly reactive to MRI scans, about 100,000 times more so than water according to the book. The patient only holds it for the scans, which is about 10 seconds, according to the book. The book says that this technique is only in early research stages, and it not used in clinics or for medical purposes or by doctors.
Breast cancer is one of the most common forms of cancer caught by woman according to the book. Once women reach a certain age (50 years, according to the book) they're advised to start taking an annual test for breast cancer, according to the book. It's an X-Ray called a mammogram (a contrast medium used for detecting breast cancer is gadolinium according to the book). MRIs do a better job for "breast cancer screening" (according to book), but they're more expensive, and book says they take longer. And sometimes they give out false alarms (book calls it "false positives")... they say that breast cancer's there, but it's not really.
We covered that CT and MRI Scanner images are made by computers. They take a ton of data (information, according to book), and make an image. And then technologist or whoever is working on the thing can have fun with it. There's multiple ways of doing this. For one thing, the person can tell the computer to highlight certain areas and tissues with bright colors (according to book; one example used is tumors). And they can ignore certain areas... and can completely take them away from the image! That's what the book says, anyway. Each image can be especially fitted for what each patient needs and for even just the patient, according to the book. It's amazing how far computers have come, and how they're used even in just medical purposes!
Saturday, December 1, 2012
Medical Central: Contrast Mediums
Today, read
more on Medical Imaging. This time, we follow something similar to a different
section… using special chemicals (called contrast mediums) to see inside the
body!
Contrast
Mediums
We all know
that X-Rays are primarily used for seeing bones. Early X-Rays could only see bones… the rest were shadow,
and couldn’t be seen. Soon after X-Rays were released, though, contrast mediums
were discovered... somewhere around 1910.
Contrast
mediums are radio-opaque liquids. In other words, they’re liquids that X-Rays
can’t pass through. They were first tested on cavaders, which is another term
for “dead bodies”. Mercury was one of the first tested, but could
only be used on cavaders… since mercury is very poisionous (sp?) to living
humans.
Different
chemicals (book says elements) started being discovered that could be used. Bismuth was one. In
fact, a painkiller called lipidiol (an oily substance, according to the book; book also says accidentally discovered by Jan Sicard, who was French doctor)
was discovered to be a good medium contrast, allowing certain machines to see
in different places, like the uterus, bladder, and spinal canal (books says the
empty area of the spine where the spinal cord is).
Contrast Mediums
can be drunk, like radioisotopes substances. But they can also be injected
directly into the bloodstream. According to the book, a young German hospital doctor
named Werner Forssmann used catheters to inject the contrast (one was foot
long!) mediums into cavaders, but wouldn’t be given permission to use on living
humans. So he used them on himself!
Book says he was reprimanded for this, but was later given a Nobel Prize with
two others. He also proved the safety of these things.
Contrast
Mediums can be used to see different stuff inside the body. The ones that use
this most often are the X-Ray machines and CT scanners, which use X-Rays. But PET
Scanners and MRI can benefit from this too. Contrast mediums allow these
machines to see bloodstreams, the intestines, spinal canal, and the inside of
the heart (coats the inside, so can see holes and stuff if exist). Bloodstreams
took a while to find a good contrast medium for, but one was eventually found (one with a familiar term: book says it was iodine),
and the first bloodstream X-Ray image (called an "angiogram" in book) was made, and more were able to be made.
Friday, November 30, 2012
Medical Central: Ultrasound
I read more on Medical Imaging. Today covered another familiar subject (also veering away from radiation): Ultrasound!
Ultrasound
We all know how bats get around: echolocation. They let loose super-high-pitched sounds, and wait for the echo to come back to their super-sensitive ears. They measure how long the sound took to echo back, and then figure out where the object that the sound bounced off is. According to the book, this is how they find bugs.
In the same way, doctors have been using a very similar technique to see inside the body. They use ultrasound (another name for super-high-pitched sound waves) probes to send ultrasound into the body. Ultrasound, despite being too high for humans to hear, is still vibrations and a type of sound. Ultrasound bounces off certain organs it can't pass through, like a fetus (still-developing and unborn baby), and comes back to the probe. A computer then measures the come-back times, does measurements and computing, and makes images. This was originally developed by a pair of Australian brothers, and, of course, has developed and upgraded over time.
The most common, and well-known version, of ultrasound use is to check the fetus in pregnant woman. A pregnant woman has an ultrasound scan at early development, and one later on. Sometimes, if it is what the book calls an "at risk pregnancy", which can be older woman, problems in the fetus whether genetic or otherwise, or more than one fetus, the woman has more. Ultrasound can also be used to check for cancers, fibiary (sp?) growths on ovaries (what it was used for at first before fetus-detecting was discovered), and checking the liquid the fetus is in (using a hollow needle in this procedure according to book). In fact, for the "growth-on-ovary" thing, a scientist working on ultrasound once used this to save a woman's life when other procedures couldn't detect the growth and helped pump up ultrasound in the medical world!
According to the book, the development of sonar (SOund Navigation and Ranging) and ultrasound flaw detector in WWII helped in the development of the ultrasound for medical purposes. A scientist figured he could use an adjusted ultrasound flaw detector, which used ultrasound to check for tears and stuff that could weaken metal vehicles according to the book, to check inside the body. Then came the "growth-on-ovary" incident described above. But people still weren't sure on ultrasound, since they didn't develop such great pictures back in the day. But the book says that it was discovered the using X-Rays on fetuses caused blood and other types of cancer, and then ultrasound became popular.
Ultrasound has gotten better, of course. The book says that they can now make 3D images, which comes into use in certain surgeries where the doctors put their tools through small cuts in the body ("keyhole" surgeries), and watch an ultrasound 3D image and work using that. Book mentions, however, that a lot more wires is needed to make a 3D ultrasound to a probe the same size as an old one which could make 2D images.
The book mentions that two Japanese scientists figured out a way to use the Doppler effect with ultrasound to see whether or not blood is flowing to or away from the probe. It goes to say that the Doppler affect is when the frequencies of a sound are heard differently if the sound-maker is going away from you or towards you (higher if towards, and lower if going away from). Then the book says the Doppler ultrasound sees if the echoes are higher than the first sound, meaning blood is flowing towards the probe, or if it's lower than the first sound, meaning it's flowing away. This can be used to diagnose many problems, like arteries hardening (in older people usually) or different heart (cardiac) problems or heart-valve (which control blood flow) problems, according to the book.
Ultrasound, with its modern 300x higher than highest frequency humans can hear sound releaser (sp?)(according to book), isn't just for checking stuff either. Ultrasound can be used for treatment as well! Ultrasound causes vibrations, which causes heat, and that can help join problems, according to the book. The book says that ultrasound treatment can help with kidney and bladder stone problems. Books says that these stones can be made in the kidney or bladder, and it's painful when they are passing through. But then the book says that ultrasound can shake these little stones apart, and then they can just go through the bloodstream.
Extra
Got some interesting animal facts from Magic School Bus yesterday, when the younger sibs were watching. We all know that animals live in cities when they're in zoos. But did you know that some animals (show uses racoons, foxes, opposums [sp?], and falcons [probably peregine]) live in the city and aren't in zoos?
What do they eat? A ton of stuff... primarily, our garbage! Talk about recycling! And there's a ton of hiding spots for them to use... the show used an old shed with a crack in it as an example. And buildings make great "cliffs" for falcons to perch on. And those birds eat other birds that fly through and have snacks in the city (show used some eating moths under light). And these animals are small enough to live in the city... bigger animals, like bears, not so much. Not only do they cause panic, they have to continually move in order to avoid people! Not enough time to survive in the end. The smaller animals, however, can have families in the city and live there. Some people now this already, in fact. Momma racoons are overprotective of their families, and do some nasty hisses if someone comes near during their active time--night (though show showed one eating worms from toppled pot during day)!
We all have heard of the sea anonome (sp?)/clown fish partnership. But many more exist... and a good deal in the coral reef! Some sea anonmes (sp?) have a partnership with hermit crabs! The plant's spines protect the crab when the crab puts it on its back (show used octopus as enemy/eater), and the plants get a free ride!
There's a partnership between Gobi fish and certain shrimp too in the coral reef. The shrimp are great diggers, but can't see well. The Gobi fish use the holes to hide, and repay the shrimp by warning them of danger. And, in the coral reef where it's an all-you-can-eat-buffet in a way, there's a lot. Sharks and remora (sp?) have a partnership too... remora (sp?) get a free ride like the sea anonome (sp?), and they eat little creatures that are annoying and "ichty" (show says) to the shark. And not all partnerships are win-win for both. A certain crab hides under a black spiny sea-plant to protect itself, but the plant gets nothing out of it.
But get this... the coral reef is a partnership! We know coral reefs are alive (mostly, some parts are skeletons of dead coral). Polops (sp?) make the coral reef, and certain algae stick onto them. Algae makes food, since they're plants, and the polops (sp?) give the algae a place to live. A safe one in the "Danger Zone" of the coral reef (not many fish live in deep sea since it has barely any food and not many hiding spots, but coral reefs give plenty of both).
Coral reefs can get sick, believe-it-or-not! When the water is polluted, polops (sp?) get rid of the algae. This can make the reef sick, and drain it of its color too (in show, copper was polluting water, believe it or not!). If the pollution is removed, the reef does have a chance, since the algae comes back too, but can take a ton of years (according to show).
Ultrasound
We all know how bats get around: echolocation. They let loose super-high-pitched sounds, and wait for the echo to come back to their super-sensitive ears. They measure how long the sound took to echo back, and then figure out where the object that the sound bounced off is. According to the book, this is how they find bugs.
In the same way, doctors have been using a very similar technique to see inside the body. They use ultrasound (another name for super-high-pitched sound waves) probes to send ultrasound into the body. Ultrasound, despite being too high for humans to hear, is still vibrations and a type of sound. Ultrasound bounces off certain organs it can't pass through, like a fetus (still-developing and unborn baby), and comes back to the probe. A computer then measures the come-back times, does measurements and computing, and makes images. This was originally developed by a pair of Australian brothers, and, of course, has developed and upgraded over time.
The most common, and well-known version, of ultrasound use is to check the fetus in pregnant woman. A pregnant woman has an ultrasound scan at early development, and one later on. Sometimes, if it is what the book calls an "at risk pregnancy", which can be older woman, problems in the fetus whether genetic or otherwise, or more than one fetus, the woman has more. Ultrasound can also be used to check for cancers, fibiary (sp?) growths on ovaries (what it was used for at first before fetus-detecting was discovered), and checking the liquid the fetus is in (using a hollow needle in this procedure according to book). In fact, for the "growth-on-ovary" thing, a scientist working on ultrasound once used this to save a woman's life when other procedures couldn't detect the growth and helped pump up ultrasound in the medical world!
According to the book, the development of sonar (SOund Navigation and Ranging) and ultrasound flaw detector in WWII helped in the development of the ultrasound for medical purposes. A scientist figured he could use an adjusted ultrasound flaw detector, which used ultrasound to check for tears and stuff that could weaken metal vehicles according to the book, to check inside the body. Then came the "growth-on-ovary" incident described above. But people still weren't sure on ultrasound, since they didn't develop such great pictures back in the day. But the book says that it was discovered the using X-Rays on fetuses caused blood and other types of cancer, and then ultrasound became popular.
Ultrasound has gotten better, of course. The book says that they can now make 3D images, which comes into use in certain surgeries where the doctors put their tools through small cuts in the body ("keyhole" surgeries), and watch an ultrasound 3D image and work using that. Book mentions, however, that a lot more wires is needed to make a 3D ultrasound to a probe the same size as an old one which could make 2D images.
The book mentions that two Japanese scientists figured out a way to use the Doppler effect with ultrasound to see whether or not blood is flowing to or away from the probe. It goes to say that the Doppler affect is when the frequencies of a sound are heard differently if the sound-maker is going away from you or towards you (higher if towards, and lower if going away from). Then the book says the Doppler ultrasound sees if the echoes are higher than the first sound, meaning blood is flowing towards the probe, or if it's lower than the first sound, meaning it's flowing away. This can be used to diagnose many problems, like arteries hardening (in older people usually) or different heart (cardiac) problems or heart-valve (which control blood flow) problems, according to the book.
Ultrasound, with its modern 300x higher than highest frequency humans can hear sound releaser (sp?)(according to book), isn't just for checking stuff either. Ultrasound can be used for treatment as well! Ultrasound causes vibrations, which causes heat, and that can help join problems, according to the book. The book says that ultrasound treatment can help with kidney and bladder stone problems. Books says that these stones can be made in the kidney or bladder, and it's painful when they are passing through. But then the book says that ultrasound can shake these little stones apart, and then they can just go through the bloodstream.
Extra
Got some interesting animal facts from Magic School Bus yesterday, when the younger sibs were watching. We all know that animals live in cities when they're in zoos. But did you know that some animals (show uses racoons, foxes, opposums [sp?], and falcons [probably peregine]) live in the city and aren't in zoos?
What do they eat? A ton of stuff... primarily, our garbage! Talk about recycling! And there's a ton of hiding spots for them to use... the show used an old shed with a crack in it as an example. And buildings make great "cliffs" for falcons to perch on. And those birds eat other birds that fly through and have snacks in the city (show used some eating moths under light). And these animals are small enough to live in the city... bigger animals, like bears, not so much. Not only do they cause panic, they have to continually move in order to avoid people! Not enough time to survive in the end. The smaller animals, however, can have families in the city and live there. Some people now this already, in fact. Momma racoons are overprotective of their families, and do some nasty hisses if someone comes near during their active time--night (though show showed one eating worms from toppled pot during day)!
We all have heard of the sea anonome (sp?)/clown fish partnership. But many more exist... and a good deal in the coral reef! Some sea anonmes (sp?) have a partnership with hermit crabs! The plant's spines protect the crab when the crab puts it on its back (show used octopus as enemy/eater), and the plants get a free ride!
There's a partnership between Gobi fish and certain shrimp too in the coral reef. The shrimp are great diggers, but can't see well. The Gobi fish use the holes to hide, and repay the shrimp by warning them of danger. And, in the coral reef where it's an all-you-can-eat-buffet in a way, there's a lot. Sharks and remora (sp?) have a partnership too... remora (sp?) get a free ride like the sea anonome (sp?), and they eat little creatures that are annoying and "ichty" (show says) to the shark. And not all partnerships are win-win for both. A certain crab hides under a black spiny sea-plant to protect itself, but the plant gets nothing out of it.
But get this... the coral reef is a partnership! We know coral reefs are alive (mostly, some parts are skeletons of dead coral). Polops (sp?) make the coral reef, and certain algae stick onto them. Algae makes food, since they're plants, and the polops (sp?) give the algae a place to live. A safe one in the "Danger Zone" of the coral reef (not many fish live in deep sea since it has barely any food and not many hiding spots, but coral reefs give plenty of both).
Coral reefs can get sick, believe-it-or-not! When the water is polluted, polops (sp?) get rid of the algae. This can make the reef sick, and drain it of its color too (in show, copper was polluting water, believe it or not!). If the pollution is removed, the reef does have a chance, since the algae comes back too, but can take a ton of years (according to show).
Thursday, November 29, 2012
Medical Central: MRI
I read more on Medical Imaging. The subject went from radiation to magnetic. Today's subject is another familiar term: MRI--Magnetic Resonance Imaging--machines.
MRI
MRI came from NMR (Nuclear Magnetic Resonance), which chemists used to figure out which atoms made up a substance. Someone realized the potential for looking inside the human body, and began to develop the MRI. The first machine, made by Damadian (who went to an university in Brooklyn, New York) was impressive, but it took the work of many scientists to create a good MRI machine (especially one who figured out how to make the image using data and showed it using math).
MRI scanners started coming into use in the mid-1980's. They were expensive, but worth it. They can do something PET and CT Scanners can't... they can see tissues!
MRI works by detecting hydrogen. Since this is primarily in water, it tracks water in the body. The MRI uses radio waves and magnets (primary one makes magnetic field stronger than Earth's natural one!) to trigger hydrogen atoms into releasing their own magnetic signals. Now, the book says these are weak signals, but the MRI can pick them up. Thanks to the atoms surrounding the hydrogen atoms, the hydrogen atoms send out slightly-different signals (according to book), but a machine attached to the MRI figures out these signals and makes an image (according to book). Now, substances with little water--like primarily-calcium bones--don't come up as well. But a lot of stuff can be seen... especially stuff surrounding by bone and cartilage. In fact, it's great for finding tumors in the pituitary gland, right under the brain and surrounded by bone, according to the book.
The book also pops up an interesting fact... this machine was also used for checking out the brain at first! In fact, today, there's something called functional MRI... AKA fMRI. This is a way of studying the brain. Japanese scientists figured out that MRI could trace blood flow in the brain. Since when a section of the brain is working it needs energy and oxygen, and therefore the blood flow increases (according to the book), this was a good way to figure out which part of the brain did what while someone was doing something. Book says that the scientists first get a baseline in which the brain rests, and then they scan the patient while doing some simple task, and then subtract the baseline, and figure out which parts of the brain were active when doing the activity. Now, there are debates on whether or not this is effective (some of it is on technique use, reports, experiments, and the fact that the brain changes functions faster than a machine can make an image) according to the book, but it's still pretty cool to me!
Like other machines in modern times, MRI machines can now make 3D images. Using pits called voxels (according to book: "volume" and "pixels" combined), a 3D image can be made. A surgeon can play around with this image as much as he wants, cutting "slices", looking at something (like a tumor) from every angle, and whatever, according to the book. The book states that this increases the chances of a successful surgery.
Now, to people with pacemakers and the little metal nets that keep an artery open, MRI machines can be dangerous because of the high-powered magnetic field. The book even says that patients going through an MRI are usually stripped of magnetic objects first. The book says that scientists once even thought that the high-powered magnetic field made the MRI dangerous, though they are now considered safe (and safer than a PET or CT Scanner, since those use radiation, according to the book).
MRI
MRI came from NMR (Nuclear Magnetic Resonance), which chemists used to figure out which atoms made up a substance. Someone realized the potential for looking inside the human body, and began to develop the MRI. The first machine, made by Damadian (who went to an university in Brooklyn, New York) was impressive, but it took the work of many scientists to create a good MRI machine (especially one who figured out how to make the image using data and showed it using math).
MRI scanners started coming into use in the mid-1980's. They were expensive, but worth it. They can do something PET and CT Scanners can't... they can see tissues!
MRI works by detecting hydrogen. Since this is primarily in water, it tracks water in the body. The MRI uses radio waves and magnets (primary one makes magnetic field stronger than Earth's natural one!) to trigger hydrogen atoms into releasing their own magnetic signals. Now, the book says these are weak signals, but the MRI can pick them up. Thanks to the atoms surrounding the hydrogen atoms, the hydrogen atoms send out slightly-different signals (according to book), but a machine attached to the MRI figures out these signals and makes an image (according to book). Now, substances with little water--like primarily-calcium bones--don't come up as well. But a lot of stuff can be seen... especially stuff surrounding by bone and cartilage. In fact, it's great for finding tumors in the pituitary gland, right under the brain and surrounded by bone, according to the book.
The book also pops up an interesting fact... this machine was also used for checking out the brain at first! In fact, today, there's something called functional MRI... AKA fMRI. This is a way of studying the brain. Japanese scientists figured out that MRI could trace blood flow in the brain. Since when a section of the brain is working it needs energy and oxygen, and therefore the blood flow increases (according to the book), this was a good way to figure out which part of the brain did what while someone was doing something. Book says that the scientists first get a baseline in which the brain rests, and then they scan the patient while doing some simple task, and then subtract the baseline, and figure out which parts of the brain were active when doing the activity. Now, there are debates on whether or not this is effective (some of it is on technique use, reports, experiments, and the fact that the brain changes functions faster than a machine can make an image) according to the book, but it's still pretty cool to me!
Like other machines in modern times, MRI machines can now make 3D images. Using pits called voxels (according to book: "volume" and "pixels" combined), a 3D image can be made. A surgeon can play around with this image as much as he wants, cutting "slices", looking at something (like a tumor) from every angle, and whatever, according to the book. The book states that this increases the chances of a successful surgery.
Now, to people with pacemakers and the little metal nets that keep an artery open, MRI machines can be dangerous because of the high-powered magnetic field. The book even says that patients going through an MRI are usually stripped of magnetic objects first. The book says that scientists once even thought that the high-powered magnetic field made the MRI dangerous, though they are now considered safe (and safer than a PET or CT Scanner, since those use radiation, according to the book).
Monday, November 26, 2012
Medical Central: SPECT and PET Scanners
Today, read something on SPECT and PET scanners. These two are actually related to each other. Once became before the other, and they are similar in quite a few ways.
SPECT Scanners
Scientists have been looking for ways to use radioactive materials other than X-Rays to help them see inside the body. One year after X-Rays were discovered, radioactivity was discovered. Scientists figured out how to tag certain substances with radioactive materials that they made (like radioactive water or glucose; these made radioactive substances are called radioisotopes). Then they could use a Geiger Counter or a scanner to track the substance on its journey throughout the body.
Two scientists made the SPECT (Single Photon Emission Computed Tomography, according to the book) scanner. It traces the tagged materials throughout the body, and keeps an eye on it, mainly by detecting photons (very tiny traces/"packs" of light or energy or radioactivity) and making images from the photons released by the radioactively-tagged substance (according to the book). When using glucose (the body's main energy source, or "food") as a tagged material, areas that use a lot of energy--like growing and dividing cells--can be detected. Since tumors also use a lot of glucose while multiplying and growing their cells, SPECT scanners are good for spotting cancers. However, they do not make images of the body or inside it. Since they're relatively cheap, though, they're still highly commonly used.
PET Scanners
Years later, however, a scientist team in an university in St. Louis, Missouri, combined a couple of different technologies (CT Scanner included) to make a better version of the SPECT Scanner... the PET (Positron Emission Tomography) Scanner! The substance is tagged with a radioactive substance that emits particles called "positrons". However, this substance released two positrons at once... in opposite directions! While there was once a spiky-helmet device, now the person is put (a picture shows a person lying down, wearing a wired hair-net thing) into a tubular area. The scan work kind of like a CT Scanner... detectors pick up the released positrons and radioactivity, and then form an image. And it takes them from all angles too.
PET Scanners took a while to come out into the medical field. But even now, they're primarily used in research, not medical purposes. All though it is used to figure out different brain disorders in the medical field (one of the first patients was a 2-year-old named Ryan Peterson who had major problems in half of his brain, and only a PET Scanner could pick the problem up. He had major surgery, where the problem-half's outer "skin" was taken away, and was acting normal pretty soon! This happened in 1985), and some other stuff (like heart stuff & problems; and a PET Scanner is still highly useful for detecting tumors and their location), it is primarily used in research.
Now, there are some problems with using PET Scanners. To get the tagged substance inside the patients, the patients have to drink something with the tagged substance inside, and then the substance rides the bloodstream and blood cells... this and, the books says, just drinking the substance can make patients nervous (makes total sense! The same method is used for getting the substances inside patients for SPECT Scanners), since the material is radioactive (in fact, for a long time, people weren't sure if using radioisotopes were safe... once scientist only felt safe about figuring this out by using them on himself!!!). The radiation only lasts a short time, though. But this makes a problem for guys who use PET Scanners... the substance has to be made on-site or very close to the PET Scanner. Because of this, not every hospital or medical place has a PET Scanner.
Also, while glucose is the primary substance that's tagged, it's not always used. For checking out the heart and its problems, for example, a type of ammonia is used. The trip via the bloodstream through the heart doesn't affect the data sent by the substance, so that's what used. Glucose doesn't really help in this department, and doesn't get much data, so this other type of ammonia is used.
SPECT Scanners
Scientists have been looking for ways to use radioactive materials other than X-Rays to help them see inside the body. One year after X-Rays were discovered, radioactivity was discovered. Scientists figured out how to tag certain substances with radioactive materials that they made (like radioactive water or glucose; these made radioactive substances are called radioisotopes). Then they could use a Geiger Counter or a scanner to track the substance on its journey throughout the body.
Two scientists made the SPECT (Single Photon Emission Computed Tomography, according to the book) scanner. It traces the tagged materials throughout the body, and keeps an eye on it, mainly by detecting photons (very tiny traces/"packs" of light or energy or radioactivity) and making images from the photons released by the radioactively-tagged substance (according to the book). When using glucose (the body's main energy source, or "food") as a tagged material, areas that use a lot of energy--like growing and dividing cells--can be detected. Since tumors also use a lot of glucose while multiplying and growing their cells, SPECT scanners are good for spotting cancers. However, they do not make images of the body or inside it. Since they're relatively cheap, though, they're still highly commonly used.
PET Scanners
Years later, however, a scientist team in an university in St. Louis, Missouri, combined a couple of different technologies (CT Scanner included) to make a better version of the SPECT Scanner... the PET (Positron Emission Tomography) Scanner! The substance is tagged with a radioactive substance that emits particles called "positrons". However, this substance released two positrons at once... in opposite directions! While there was once a spiky-helmet device, now the person is put (a picture shows a person lying down, wearing a wired hair-net thing) into a tubular area. The scan work kind of like a CT Scanner... detectors pick up the released positrons and radioactivity, and then form an image. And it takes them from all angles too.
PET Scanners took a while to come out into the medical field. But even now, they're primarily used in research, not medical purposes. All though it is used to figure out different brain disorders in the medical field (one of the first patients was a 2-year-old named Ryan Peterson who had major problems in half of his brain, and only a PET Scanner could pick the problem up. He had major surgery, where the problem-half's outer "skin" was taken away, and was acting normal pretty soon! This happened in 1985), and some other stuff (like heart stuff & problems; and a PET Scanner is still highly useful for detecting tumors and their location), it is primarily used in research.
Now, there are some problems with using PET Scanners. To get the tagged substance inside the patients, the patients have to drink something with the tagged substance inside, and then the substance rides the bloodstream and blood cells... this and, the books says, just drinking the substance can make patients nervous (makes total sense! The same method is used for getting the substances inside patients for SPECT Scanners), since the material is radioactive (in fact, for a long time, people weren't sure if using radioisotopes were safe... once scientist only felt safe about figuring this out by using them on himself!!!). The radiation only lasts a short time, though. But this makes a problem for guys who use PET Scanners... the substance has to be made on-site or very close to the PET Scanner. Because of this, not every hospital or medical place has a PET Scanner.
Also, while glucose is the primary substance that's tagged, it's not always used. For checking out the heart and its problems, for example, a type of ammonia is used. The trip via the bloodstream through the heart doesn't affect the data sent by the substance, so that's what used. Glucose doesn't really help in this department, and doesn't get much data, so this other type of ammonia is used.
Sunday, November 25, 2012
Dinosaur Central: Triceratops
Today, the focus was once again on dinosaurs... I read a book on one of the infamous dinosaurs... the Triceratops!
Triceratops
Usually, when we're introduced to dinosaurs, the Triceratops comes up... it's also one of the ones most seen in movies and books about the ancient reptiles. We get to know them by their three horns on their faces. In fact, the name "triceratops" has the meaning of "three-horned face". Makes sense, doesn't it?
Triceratops are part of a group of dinos called ceratopsians. "Ceratopsian" means "Horned-Faced". There's about 30 different kinds of ceratopsians, each with an unique number of horn-faces, and their frills. Yes, even the triceratops has a bony frill. It's around its head's back. While there are similarities, ceratopsians are very different... a different ceratopsian, the styracosaurus, looks very different from the triceratops!
Styracosauruses (sp?) had a lot more horns. Most of these horns were around the edge of its frill, which has two large heart-shape-like humps with hollow "valleys" within and two small "wing-humps" near its eyes' position, and its nose-horn is smaller than the triceratops. Triceratops have round frills, their two big horns above its eyes, and it has a pretty big nose-horn. Their skin were probably different colors too, but since we only have artists' interpretations to go on and none of us were in prehistoric times, none of us know for sure.
Triceratops were the largest ceratopsian ever, with a length of 30 feet (9 meters) and a height of 10 feet (3 meters). Believe it or not, its head was a long as its body was high... 10 feet (3 meters)! It was also the heaviest ceratopsian, weighed around 5 tons (4.5 t)! Yikes!
Paleontologists believe that the brain wasn't big, however. They guess that the Triceratops' brain was only about the size of a human's fist. The book says that Triceratops didn't have very sharp senses or smarts. The book also says that paleontologists also believe that the Triceratops weren't fast, mainly because of its body shape and size. Not a concern for eating plants (Triceratops are herbivores), but Triceratops were often prey to the T-Rex. The book says that Triceratops probably fought back, but couldn't win against the T-Rex.
Triceratops live in the late Cretaceous (book says the Cretaceous was 89-65 million years ago). They had different kinds of dino-neighbors, like the T-Rex and ankylosaurus (one of the armored dinos according to the book). They lived in areas that the Rockies cut through today... the U.S. states of Wyoming, South Dakota, Montana, Colorado, and Canada's provinces of Saskatchewan and Alberta are listed in the book. The book says that the Rockies have a lot of sedimentary rock, which fossils are made of.
The book says scientists use fossils to figure out all they can about extinct animals by searching for clues in the fossils. Also, scientists use the geologic time system. This chops Earth-history into smaller bits.
Triceratops lived in heavily-forested areas. The books says that the climate was similar to modern tropical ones, and that the climate had been hot and humid, but was beginning to cool, and that North America's inner sea was beginning to dry up.
Triceratops
Usually, when we're introduced to dinosaurs, the Triceratops comes up... it's also one of the ones most seen in movies and books about the ancient reptiles. We get to know them by their three horns on their faces. In fact, the name "triceratops" has the meaning of "three-horned face". Makes sense, doesn't it?
Triceratops are part of a group of dinos called ceratopsians. "Ceratopsian" means "Horned-Faced". There's about 30 different kinds of ceratopsians, each with an unique number of horn-faces, and their frills. Yes, even the triceratops has a bony frill. It's around its head's back. While there are similarities, ceratopsians are very different... a different ceratopsian, the styracosaurus, looks very different from the triceratops!
Styracosauruses (sp?) had a lot more horns. Most of these horns were around the edge of its frill, which has two large heart-shape-like humps with hollow "valleys" within and two small "wing-humps" near its eyes' position, and its nose-horn is smaller than the triceratops. Triceratops have round frills, their two big horns above its eyes, and it has a pretty big nose-horn. Their skin were probably different colors too, but since we only have artists' interpretations to go on and none of us were in prehistoric times, none of us know for sure.
Triceratops were the largest ceratopsian ever, with a length of 30 feet (9 meters) and a height of 10 feet (3 meters). Believe it or not, its head was a long as its body was high... 10 feet (3 meters)! It was also the heaviest ceratopsian, weighed around 5 tons (4.5 t)! Yikes!
Paleontologists believe that the brain wasn't big, however. They guess that the Triceratops' brain was only about the size of a human's fist. The book says that Triceratops didn't have very sharp senses or smarts. The book also says that paleontologists also believe that the Triceratops weren't fast, mainly because of its body shape and size. Not a concern for eating plants (Triceratops are herbivores), but Triceratops were often prey to the T-Rex. The book says that Triceratops probably fought back, but couldn't win against the T-Rex.
Triceratops live in the late Cretaceous (book says the Cretaceous was 89-65 million years ago). They had different kinds of dino-neighbors, like the T-Rex and ankylosaurus (one of the armored dinos according to the book). They lived in areas that the Rockies cut through today... the U.S. states of Wyoming, South Dakota, Montana, Colorado, and Canada's provinces of Saskatchewan and Alberta are listed in the book. The book says that the Rockies have a lot of sedimentary rock, which fossils are made of.
The book says scientists use fossils to figure out all they can about extinct animals by searching for clues in the fossils. Also, scientists use the geologic time system. This chops Earth-history into smaller bits.
Triceratops lived in heavily-forested areas. The books says that the climate was similar to modern tropical ones, and that the climate had been hot and humid, but was beginning to cool, and that North America's inner sea was beginning to dry up.
Friday, November 23, 2012
Medical Central: CT Scanners
I read another chapter in that neat book about Medical Imaging equipment. The next subject sort-of came with the X-Ray subject... CT Scanners!
CT Scanners
First, something about X-Rays. Bones appear on the X-Ray photos because they absorb the X-Rays, keeping them from hitting and reacting with the detectors or photographic material. Skin, organs, and other soft body parts, don't... as much. More X-Rays pass through, and hit the detectors or photographic material. But they do absorb a little... there's usually a shadow of them in the X-Ray photo.
CT (computed tomography) Scanners use this fact to make their own images. They use X-Rays and detectors. X-Rays pass through the body, hit the detectors, and the computer uses information to make an image of a "slice" of the body. In fact, tomography means "a picture of a plane" in Greek, according to the book, which is basically what a "slice" is. This invention was developed by an English scientist by the name of Hounsfield in 1967.
At first, it took a long time to get enough data to construct a picture, and even for the computer to use that data to make the picture! The final image took days to get there.
But developments were made fast. Even just 10 years later, CT Scanners were making images in less than a second (and, according to the book, they're developing faster ones and those faster CT Scanners are to come, believe it or not). They were once black-and-white, but now the computer can now be told to add color. And it was once in 2D, but now computers can use CT Scanner information to make 3D images (there's a picture of one in the book, and it's hard not to believe that it was a drawing!). And the radiologist can tinker with this 3D image as much as her or she wants.
And CT Scanners were once used to just scan the brain, mainly for tumors (AKA, the main problem of cancer; this scan was usually used to determine the tumor's location before surgery), but now there are full-body scans. In fact, some people used to use full-body CT scans for their baseline medical records. But studies discovered that this is dangerous... while CT Scanners use relatively low dosages of X-Rays, a full-body scan causes the body to absorb a lot of X-Rays. X-Rays, especially in high dosages, are dangerous and can cause cancers. Not worth risking!
But CT Scanners are still highly useful. Especially in the chest and lungs area... they are great in figuring out problems in those areas. And, of course, they're still used to scan the brain for problems and cancer. And they're a big help in the emergency room... they can figure out the major problems right away in a ER patient going through a CT Scanner using this device.
Some of us know CT scans by the term "CAT Scans", especially at first. CAT stands for "computed axial tomography". But medical personal and places (like hospitals and such) now prefer the technical term of CT (Computed Tomography) Scans and CT Scanners (instead of CAT Scanners).
Extra
You know, Magic School Bus is an awesome show. My younger sibs were watching it, but I got a few electricity and smelling facts.
We know batteries store energy. But did you know that they push the energy (electricity) through their path (which is called a circuit?). The electricity goes around and round in a circular path (not always the same shape as "circular" indicates, but goes back to the start always), and if there's a break, everything comes to a complete halt! This even happens if there's no break in the path, but the battery is no good. If there's a light bulb filament along the way, the electricity powers up (by heating up) the filament, making it glow.
Of course, there's an on/off switch... usually. No-go if there's a break or useless battery anyway! And different stuff have different power levels. Flashlights (example in show) is safe, of course. But a lot of other house-hold items have dangerous power levels. The show wisely added a warning to be careful with bare wires and different electrical items, as well as no playing with them. And the electrical bits are positive and negative (they have no color, but the show added them for help) but they're called plus and minus to help determine which is which.
A fact we all know: we smell with our noses. But the question is... how? Things that give off a smell let loose smell molecules (which no one can see, since they're so small). Those molecules wander up our nose, and fit themselves into smell receptors built just for them. They go into certain spots like pieces in a jigsaw puzzle or a machine part in the machine (that's the best way I could describe those scenes). Then our brain is triggered to identify the smell. If our nose is stuffed up, those molecules can't reach and/or get into the receptors. And since our sense of smell is connected to our sense of taste... that little problem causes us to lose our sense of taste, or make things taste different.
Some things release more smell molecules than others, or some objects' smell molecules cause a bigger reaction from the receptors, making the smell stronger. But some things (example in show: rocks), don't release any smell molecules. But here's another curve-ball: some objects do release smell molecules but those don't trigger a reaction in our receptors (example in show: water. Yeah, water releases smell molecules! That's hard to believe, but true and awesome!).
CT Scanners
First, something about X-Rays. Bones appear on the X-Ray photos because they absorb the X-Rays, keeping them from hitting and reacting with the detectors or photographic material. Skin, organs, and other soft body parts, don't... as much. More X-Rays pass through, and hit the detectors or photographic material. But they do absorb a little... there's usually a shadow of them in the X-Ray photo.
CT (computed tomography) Scanners use this fact to make their own images. They use X-Rays and detectors. X-Rays pass through the body, hit the detectors, and the computer uses information to make an image of a "slice" of the body. In fact, tomography means "a picture of a plane" in Greek, according to the book, which is basically what a "slice" is. This invention was developed by an English scientist by the name of Hounsfield in 1967.
At first, it took a long time to get enough data to construct a picture, and even for the computer to use that data to make the picture! The final image took days to get there.
But developments were made fast. Even just 10 years later, CT Scanners were making images in less than a second (and, according to the book, they're developing faster ones and those faster CT Scanners are to come, believe it or not). They were once black-and-white, but now the computer can now be told to add color. And it was once in 2D, but now computers can use CT Scanner information to make 3D images (there's a picture of one in the book, and it's hard not to believe that it was a drawing!). And the radiologist can tinker with this 3D image as much as her or she wants.
And CT Scanners were once used to just scan the brain, mainly for tumors (AKA, the main problem of cancer; this scan was usually used to determine the tumor's location before surgery), but now there are full-body scans. In fact, some people used to use full-body CT scans for their baseline medical records. But studies discovered that this is dangerous... while CT Scanners use relatively low dosages of X-Rays, a full-body scan causes the body to absorb a lot of X-Rays. X-Rays, especially in high dosages, are dangerous and can cause cancers. Not worth risking!
But CT Scanners are still highly useful. Especially in the chest and lungs area... they are great in figuring out problems in those areas. And, of course, they're still used to scan the brain for problems and cancer. And they're a big help in the emergency room... they can figure out the major problems right away in a ER patient going through a CT Scanner using this device.
Some of us know CT scans by the term "CAT Scans", especially at first. CAT stands for "computed axial tomography". But medical personal and places (like hospitals and such) now prefer the technical term of CT (Computed Tomography) Scans and CT Scanners (instead of CAT Scanners).
Extra
You know, Magic School Bus is an awesome show. My younger sibs were watching it, but I got a few electricity and smelling facts.
We know batteries store energy. But did you know that they push the energy (electricity) through their path (which is called a circuit?). The electricity goes around and round in a circular path (not always the same shape as "circular" indicates, but goes back to the start always), and if there's a break, everything comes to a complete halt! This even happens if there's no break in the path, but the battery is no good. If there's a light bulb filament along the way, the electricity powers up (by heating up) the filament, making it glow.
Of course, there's an on/off switch... usually. No-go if there's a break or useless battery anyway! And different stuff have different power levels. Flashlights (example in show) is safe, of course. But a lot of other house-hold items have dangerous power levels. The show wisely added a warning to be careful with bare wires and different electrical items, as well as no playing with them. And the electrical bits are positive and negative (they have no color, but the show added them for help) but they're called plus and minus to help determine which is which.
A fact we all know: we smell with our noses. But the question is... how? Things that give off a smell let loose smell molecules (which no one can see, since they're so small). Those molecules wander up our nose, and fit themselves into smell receptors built just for them. They go into certain spots like pieces in a jigsaw puzzle or a machine part in the machine (that's the best way I could describe those scenes). Then our brain is triggered to identify the smell. If our nose is stuffed up, those molecules can't reach and/or get into the receptors. And since our sense of smell is connected to our sense of taste... that little problem causes us to lose our sense of taste, or make things taste different.
Some things release more smell molecules than others, or some objects' smell molecules cause a bigger reaction from the receptors, making the smell stronger. But some things (example in show: rocks), don't release any smell molecules. But here's another curve-ball: some objects do release smell molecules but those don't trigger a reaction in our receptors (example in show: water. Yeah, water releases smell molecules! That's hard to believe, but true and awesome!).
Monday, November 19, 2012
Medical Central: X-Rays
I started this awesome book on different stuff doctors use to see inside our bodies. They use these scanners, which uses different waves and such, to actually see inside us! This process is called Medical Imaging, and it gives doctors an extra step in figuring out what's wrong with us. Without it, there are two other methods: listening to symptoms, and an examination that includes touching, looking at, and listening to our bodies. Since the problem is usually inside us, and many illnesses have similar symptoms, using only these two can be limiting and tricky for diagnostics (process of identifying what's wrong with the patient). But with Medical Imaging, things become easier.
And it started with X-Rays!
X-Rays
We all know X-Rays. When we've hurt our limbs, like a leg or arm, the docs have us get an X-Ray to see our bones and make sure nothing's broken. They are the most common scanner, and honestly the most well-known. They're relatively cheap to make, so doctors use a lot! There's a lot of types as well, like a X-Ray TV system which is an upgrade from flouroscopes (sp?) which made "movies" of real-time moving X-Rays images (made by Thomas Edison!). TV-X-Rays use similar techniques, but use an image enhancer to make the picture sequence better and put it on TV. And there's a process in where doctors inject certain chemicals into bloodstreams so that they can be seen on an X-Ray as well. In fact, the first CAT scan, used in a small London hospital when first time, used X-Rays to scan a woman's brain (the device that did this is called a CT, which stands for computed tomography, scanner).
X-Rays were discovered by a German scientist (who moved to the Netherlands when 3, and got an award for his X-Ray research). He was experimenting with a cathode tube (the type used in old-style TVs and the bulky computer monitors). That's basically a tube with the air vacuumed out and wires attached. Electricity causes certain energy to go from one end to the tube then to other other (negative end [cathode] to positive end [anthode][sp?]). This causes a glow, but the light doesn't go very far... only a few centimeters! But the scientist noticed a flourscent (sp?) material glowing in the dark room, and realized that a different radiation was emanating from the tube. He named this new radiation "X-Rays".
A bunch of experiments followed. Somehow, probably by accident, put his hand in the way while making a "photograph" (X-Rays cause special photographic material to darken, and less-hit areas lighten, making a photo), and the X-Rays couldn't go through his hand, so... Ta-da! (sp?) The first X-Ray image! He even did one later with his wife's hand... and the X-Rays couldn't even get past her ring!
Then he released his discovery to the public. Doctors soon realized how useful X-Rays could be to medicine, and a doctor use an X-Ray image only two months later!
X-Rays are part of the electromagnetic spectrum. Everything on the Electromagnetic spectrum travels at the speed of light, but they have different frequencies... AKA, different energy levels. Normal light that we see by is in the middle of the spectrum, microwaves and infrared are on the low-level end... and X-Rays are on the high-level bit.
This, of course, makes X-Rays dangerous. But few people realized that at first. Maybe people died from overexposure and the long-term affects (like cancer) of absorbing too much X-Ray radiation, including someone who worked with Edison! Some people realized the danger, but were ignored for a long time. X-Rays were even used for tiny things... some people had hand-scanners, and barber shops had "Foot-O-Scopes" which let people see their feet bones! Of course, people eventually realized the dangers. A detector was made for people who worked with X-Rays... a card with photographic material which got dark when too much radiation was absorbed (a similar detector is still used in modern times).
X-Rays got better with time, like anything. This may be hard to believe, but once upon a time, it took two hours of X-Ray absorbing to make a photo! This eventually got cut down to seconds, and even to where multiple pictures could be taken in a few seconds! And process to improve the picture (like moving metal grills to eliminate blurs and "snow" on the photo) were made.
In fact, in 2000, digital X-Rays popped up. Now electrical detectors, instead of photo material, could pick up X-Rays and send a code which explained how much hit them to a computer. The computer translated the code, made a photo, and then the photo could be stored on disks or wherever, looked at, sent to a different hospital to get a different doctor's opinion, and printed out! These X-Ray images could also be used for permanent records and whatnot. And there's no need for chemicals or darkrooms to develop the photo (since photo material was what used to be used, and had to be developed like normal photos, like what was made with non-digital cameras)! That's cool!
And it started with X-Rays!
X-Rays
We all know X-Rays. When we've hurt our limbs, like a leg or arm, the docs have us get an X-Ray to see our bones and make sure nothing's broken. They are the most common scanner, and honestly the most well-known. They're relatively cheap to make, so doctors use a lot! There's a lot of types as well, like a X-Ray TV system which is an upgrade from flouroscopes (sp?) which made "movies" of real-time moving X-Rays images (made by Thomas Edison!). TV-X-Rays use similar techniques, but use an image enhancer to make the picture sequence better and put it on TV. And there's a process in where doctors inject certain chemicals into bloodstreams so that they can be seen on an X-Ray as well. In fact, the first CAT scan, used in a small London hospital when first time, used X-Rays to scan a woman's brain (the device that did this is called a CT, which stands for computed tomography, scanner).
X-Rays were discovered by a German scientist (who moved to the Netherlands when 3, and got an award for his X-Ray research). He was experimenting with a cathode tube (the type used in old-style TVs and the bulky computer monitors). That's basically a tube with the air vacuumed out and wires attached. Electricity causes certain energy to go from one end to the tube then to other other (negative end [cathode] to positive end [anthode][sp?]). This causes a glow, but the light doesn't go very far... only a few centimeters! But the scientist noticed a flourscent (sp?) material glowing in the dark room, and realized that a different radiation was emanating from the tube. He named this new radiation "X-Rays".
A bunch of experiments followed. Somehow, probably by accident, put his hand in the way while making a "photograph" (X-Rays cause special photographic material to darken, and less-hit areas lighten, making a photo), and the X-Rays couldn't go through his hand, so... Ta-da! (sp?) The first X-Ray image! He even did one later with his wife's hand... and the X-Rays couldn't even get past her ring!
Then he released his discovery to the public. Doctors soon realized how useful X-Rays could be to medicine, and a doctor use an X-Ray image only two months later!
X-Rays are part of the electromagnetic spectrum. Everything on the Electromagnetic spectrum travels at the speed of light, but they have different frequencies... AKA, different energy levels. Normal light that we see by is in the middle of the spectrum, microwaves and infrared are on the low-level end... and X-Rays are on the high-level bit.
This, of course, makes X-Rays dangerous. But few people realized that at first. Maybe people died from overexposure and the long-term affects (like cancer) of absorbing too much X-Ray radiation, including someone who worked with Edison! Some people realized the danger, but were ignored for a long time. X-Rays were even used for tiny things... some people had hand-scanners, and barber shops had "Foot-O-Scopes" which let people see their feet bones! Of course, people eventually realized the dangers. A detector was made for people who worked with X-Rays... a card with photographic material which got dark when too much radiation was absorbed (a similar detector is still used in modern times).
X-Rays got better with time, like anything. This may be hard to believe, but once upon a time, it took two hours of X-Ray absorbing to make a photo! This eventually got cut down to seconds, and even to where multiple pictures could be taken in a few seconds! And process to improve the picture (like moving metal grills to eliminate blurs and "snow" on the photo) were made.
In fact, in 2000, digital X-Rays popped up. Now electrical detectors, instead of photo material, could pick up X-Rays and send a code which explained how much hit them to a computer. The computer translated the code, made a photo, and then the photo could be stored on disks or wherever, looked at, sent to a different hospital to get a different doctor's opinion, and printed out! These X-Ray images could also be used for permanent records and whatnot. And there's no need for chemicals or darkrooms to develop the photo (since photo material was what used to be used, and had to be developed like normal photos, like what was made with non-digital cameras)! That's cool!
Sunday, November 18, 2012
Dinosaur Central: Velociraptors
I got some cool data from a dinosaur book. While it did have some general dinosaur facts, the book's main focus was on Velociraptors.
Dinosaurs
The Age of Dinosaurs is known as the Mesozoic Era. It started around 228 million years ago, and ended 65 million years ago. Scientists think that a huge asteroid that hit the Gulf of Mexico is what ended the Mesozoic Era by kicking up a huge cloud of dust, which made the Earth cooler (which was normally a warm place, and the book says that extremes were only a few), which killed plants, which made herbivores (plant-eaters) starve, which made meat-eaters starve to death, since they had no prey. Now, some creatures like mice survived the disaster, but that's what scientists think what happened.
You may know this, but the Mesozoic Era is chomped up into three main sections. The first is the Triassic, whose late ages began 228 million years ago, and ended 206 million years ago, lasting about 42 million years. It was in these late stages that dinosaurs and the small mammals supposedly appeared. The other two is the Jurassic, going from 206-114 millions years ago, lasting 61 million years, and the Cretaceous, which went from 114-65 million years ago, lasting the longest of the three periods with 79 million years.
Dinosaurs supposedly ruled the Earth for 160 million years. But why? Scientists believe that this is because they were able to put their feet and legs directly under their body, giving them an advantage over other reptiles (yes, they were reptiles).
We all know dinosaur means "terrible lizard". But did you know it came from the word dinosauria, which was invented by an English dude named Richard Owen, who was indeed a scientist? The word is made from the Greek words deinos and sauros, which means "terrible lizard".
Scientists classify dinosaurs, of course. But they can chop all dinosaurs into two groups... by the shape of their hipbones! The ones with hips like modern birds are Ornithischians, which were all herbivores. This group includes Thryophorans (which include 4-legged stegosaurians like our friend the Stegosouarus), two other groups (which are ornithopods), which have dinos like Edmontosaurus and marginocephalians. The other hipbone group is the modern-lizard-like group: the Saurischians, which have theropods (which includes the most famous T-Rex, other 2-legged meat-eaters, and possibly have birds for a branch), and sauropods like the other famous dinosaur the Brachiousaurus.
Now, to the Velociraptors!
Velociraptors
I believe this was a great move, but the book clearly stated that the Raptors in the movie Jurassic Park were not Velociratpors. And there are a few pointers in that directions. Velociraptors, unlike the Jurassic Park Raptors, hunted by themselves and not in packs. Also, Jurassic Park takes place in a big jungle-like enviroment with plains, but scientists believe that Velociraptors lived in the desert... more specially, the Gobi Desert in Asia (part of which is China), where their fossils were found.
Velociraptors and Jurassic Park Raptors do share a few commons, though. Both of them have this big, special claw. Scientists aren't overly sure what the Velociraptors did with their crescent-shaped claw. It may have been for slashing throats or guts when hunting, or killing anything that got too close, or it may have helped the Velociraptor in grabbing a prey's back to pull it down and kill it.
Velociraptors weren't overly big. They were only about 6 ft (2 m) long, and weighed from 22-33 lbs (10-15 kg). This limited their hunting options... they hunted only small animals, like mice and shrew, and other small dinosaurs. In fact, there's an interesting story behind a fossil where a Velociraptor and a Protoceratops (Pig-sized dino with beak mouth and bony frill for a neck-guard that lived in same area as Velociraptors) are tangled. Scientists believe that the Velociraptor killed the Protoceratops, which fell on the Velociraptor. The Velociraptor was stuck, and basically starved to death. And then sand covered the two, and they ended up fossilized (which ended up in a museum).
Living in the desert makes things tricky too. Velociraptors have to be careful where they plop their eggs, since it has to be in the shade. And then animals who like shade and come out at night sometimes go after eggs. Speaking of living places, Velociraptors lived in the late Cretaceous.
It was once believed that all dinosaurs were cold-blooded. But Velociraptors are fast. This started scientists to believing that some dinosaurs--at least ones of the Velociraptor's family (Dromeosauride, which includes troodons) are warm-blooded! Part of the Velociraptor's speed is due to its hollow, lightweight bones. Sounds familiar? Members of the Dromeosauride family are similar to birds... scientists believe them to be cousins! Ever since the discovery of a Microraptor (cousin and closest relative to the Velociraptor) fossil with feathers, they even believe that Velociraptors and other similar creatures had feathers!
Dinosaurs
The Age of Dinosaurs is known as the Mesozoic Era. It started around 228 million years ago, and ended 65 million years ago. Scientists think that a huge asteroid that hit the Gulf of Mexico is what ended the Mesozoic Era by kicking up a huge cloud of dust, which made the Earth cooler (which was normally a warm place, and the book says that extremes were only a few), which killed plants, which made herbivores (plant-eaters) starve, which made meat-eaters starve to death, since they had no prey. Now, some creatures like mice survived the disaster, but that's what scientists think what happened.
You may know this, but the Mesozoic Era is chomped up into three main sections. The first is the Triassic, whose late ages began 228 million years ago, and ended 206 million years ago, lasting about 42 million years. It was in these late stages that dinosaurs and the small mammals supposedly appeared. The other two is the Jurassic, going from 206-114 millions years ago, lasting 61 million years, and the Cretaceous, which went from 114-65 million years ago, lasting the longest of the three periods with 79 million years.
Dinosaurs supposedly ruled the Earth for 160 million years. But why? Scientists believe that this is because they were able to put their feet and legs directly under their body, giving them an advantage over other reptiles (yes, they were reptiles).
We all know dinosaur means "terrible lizard". But did you know it came from the word dinosauria, which was invented by an English dude named Richard Owen, who was indeed a scientist? The word is made from the Greek words deinos and sauros, which means "terrible lizard".
Scientists classify dinosaurs, of course. But they can chop all dinosaurs into two groups... by the shape of their hipbones! The ones with hips like modern birds are Ornithischians, which were all herbivores. This group includes Thryophorans (which include 4-legged stegosaurians like our friend the Stegosouarus), two other groups (which are ornithopods), which have dinos like Edmontosaurus and marginocephalians. The other hipbone group is the modern-lizard-like group: the Saurischians, which have theropods (which includes the most famous T-Rex, other 2-legged meat-eaters, and possibly have birds for a branch), and sauropods like the other famous dinosaur the Brachiousaurus.
Now, to the Velociraptors!
Velociraptors
I believe this was a great move, but the book clearly stated that the Raptors in the movie Jurassic Park were not Velociratpors. And there are a few pointers in that directions. Velociraptors, unlike the Jurassic Park Raptors, hunted by themselves and not in packs. Also, Jurassic Park takes place in a big jungle-like enviroment with plains, but scientists believe that Velociraptors lived in the desert... more specially, the Gobi Desert in Asia (part of which is China), where their fossils were found.
Velociraptors and Jurassic Park Raptors do share a few commons, though. Both of them have this big, special claw. Scientists aren't overly sure what the Velociraptors did with their crescent-shaped claw. It may have been for slashing throats or guts when hunting, or killing anything that got too close, or it may have helped the Velociraptor in grabbing a prey's back to pull it down and kill it.
Velociraptors weren't overly big. They were only about 6 ft (2 m) long, and weighed from 22-33 lbs (10-15 kg). This limited their hunting options... they hunted only small animals, like mice and shrew, and other small dinosaurs. In fact, there's an interesting story behind a fossil where a Velociraptor and a Protoceratops (Pig-sized dino with beak mouth and bony frill for a neck-guard that lived in same area as Velociraptors) are tangled. Scientists believe that the Velociraptor killed the Protoceratops, which fell on the Velociraptor. The Velociraptor was stuck, and basically starved to death. And then sand covered the two, and they ended up fossilized (which ended up in a museum).
Living in the desert makes things tricky too. Velociraptors have to be careful where they plop their eggs, since it has to be in the shade. And then animals who like shade and come out at night sometimes go after eggs. Speaking of living places, Velociraptors lived in the late Cretaceous.
It was once believed that all dinosaurs were cold-blooded. But Velociraptors are fast. This started scientists to believing that some dinosaurs--at least ones of the Velociraptor's family (Dromeosauride, which includes troodons) are warm-blooded! Part of the Velociraptor's speed is due to its hollow, lightweight bones. Sounds familiar? Members of the Dromeosauride family are similar to birds... scientists believe them to be cousins! Ever since the discovery of a Microraptor (cousin and closest relative to the Velociraptor) fossil with feathers, they even believe that Velociraptors and other similar creatures had feathers!
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