That's not exactly a common mix. Was this guy trying out for the "Most Random Acid Cocktail" award?
Apparently what was going on was that Belousov was trying to generate an inorganic analog to the Krebs cycle at the time he discovered his oscillating reaction. Instead of using enzymes, he was using oxidizing agents like potassium bromate and cerium(IV)sulfate to try to interconvert a series of carboxylic acids.
Yes, oscillating chemical reactions work just like a damped harmonic oscillator system. Two (or more) competing reactions keep pushing the system back and forth through equilibrium. Unless outside energy is being pumped into the system, over time, this reaction will slow down and eventually reach equilibrium. Just as with a thermodynamic heat engine, the competing reactions in an oscillating system like the B-Z reaction cannot cycle with 100% efficiency. With each stroke of the reaction engine, energy will be lost as waste heat, and eventually the reactions involved will be unable to surmount the activation energy barriers.
Most now offer Twitter feeds of major breaking news headlines, while the Daily Mail recently pioneered an iPhone application providing users with a one-click facility for reporting suspicious behaviour by migrants or gays.
Well, Perftoran and the other perfluorocarbon based oxygen carriers have their own drawbacks, many of which have to do directly with their non-biological nature. In particular, pure perfluorocarbons are not soluble in blood, so they must be formulated as emulsions of tiny PFC globules emulsified by egg phosphatide protein. Even with emulsion, most PFCs are much denser than water, and tend to settle out over time. these globules are too large, the body's immune system will attack them. Perfluorocarbons also cannot be metabolized like proteins. In some respects, this is an advantage over hemoglobin-analogs, which have toxic metabolic wastes, but PFC accumulation could present a serious problem with long-term administration.
Also, storage has proven to be an issue with perfluorocarbon formulations. PFC can be stable several years if kept frozen; it must be thawed before use. While the shelf-life is atractive, the storage requirements make it difficult to use as an emergency blood alternative. There is still a place for PFC-based blood substitutes; indeed, they've proven useful in preserving organs for transplant. Their drawbacks, however, suggest there is also a place for heme-based oxygen carrier therapeutics.
You would not need to solve the protein folding problem in order to crack this form of cryptography. It is not as though data is encoded in protein conformation using this technique. In fact, this technique would be unlikely to generate well-formed proteins at all. According to the paper, the method does not actually use real nucleic acids or proteins, or even very accurately simulate their properties in biological transcription or translation. The paper is even titled "A Pseudo DNA Cryptography Method." The author is using transcription and translation as a model for the general data flow present in this scheme, but the author points out that strictly hewing to the biological splicing scheme would introduce extra vulnerabilities, since it would be possible to identify from the final protein sequence places where splicing occured.
On the subject of vulnerabilities, this method, as admitted in the paper, is a symmetric substitution cipher. You still need a secure channel to perform key exchange (the key here contains the locations and lengths of spliced out introns). If an eavesdropper gets ahold of the protein (ciphertext), a simple lookup of codons gets the eavesdropper back to the post-spliced RNA. The unique challenge of this cipher is to determine where splicing occured in order to get back to the pre-spliced RNA (which is a simple complement of the DNA sequence, which in turn is an easy substitution cipher away from the plaintext). While a clever way to implement it, the intron splicing in this method is really no different than the mechanisms used to confuse plaintexts in block ciphers like DES, and it is subject to the same vulnerabilities like differential attack.
As a 27-year old, I realize that I have completely spent the peak years of my intellectual capacity having made no greater contribution to the advancement of the human race than a few hundred Slashdot posts....
Locally (to the individual atoms, for example) a Mobius molecule is double-sided. Each carbon atom is fixed in a plane in graphene, though the point here is that the plane is interestingly warped. A chlorine atom could attack a carbon atom from above the plane and a bromine atom could attack from below the plane, and that would be a physically meaningful description. "Above" and "below" are of course arbitrary distinctions; let's use "a" and "b" in this post. From the perspective of Carbon #1 of the 150 carbon atoms in this molecule, the situation is nothing special; there's a bit more bond strain from the way the lattice is twisted, but it still generally behaves like a carbon atom.
What makes a Mobius molecule interesting is when you something else along its surface. For example, kinesin is a protein that works like a set of molecular legs. Picture a regular, non-Mobius single-walled carbon nanotube, a rolled-up sheet of graphene. This tube has an exterior surface (the "a" position)and an interior surface ("b")- it is two sided. To get a kinesin molecule from the exterior surface to the interior surface or vice versa, you must either cut through the graphene lattice or walk to an edge of the cylinder and flip around. There is not a smooth, continuous path from position Carbon #1-a to #1-b for a regular nanotube.
However, for a Mobius nanostrip, that added half-twist makes the "exterior surface" continuous with the "interior surface," making a smooth path possible. If you place kinesin at Carbon #1-a and have it walk around the strip, halfway through the course (for a strip with one half-twist), the kinesin will be at Carbon #1-b (in other words, back at Carbon #1, but in a local sense, on the other side of the sheet), and its orientation will be flipped 180 degrees from the original. If the kinesin keeps going, eventually it returns to its original orientation at Carbon #1-a. If you put a kinesin molecule at both 1-a and 1-b and sent them off walking in opposite directions, they would eventually collide.
Locally, 1-a is on the opposite side of 1-b, but a kinesin molecule can smoothly and continuously walk from 1-a to 1-b (or any other point) without breaking bonds in the graphene lattice or flipping around an edge to another side. Therefore, in terms of its entire shape, a Mobius molecule is one-sided.
I think you could make a molecular Klein bottle, though of course you would have the same limitation as for any Klein bottle immersed in three dimensions- a self-intersection would be necessary. This would probably rule out a physically realizable Klein bottle made purely out of graphene, as a self-intersection would either involve carbon atoms bonding to 5 or 6 other carbon atoms (extraordinarily unlikely) or bonds with significant angle strain and steric hindrance if you tried to squeeze the self-intersecting tube through the lattice instead of bonding to it. If you didn't mind including some higher-valent atoms rather than just carbon, it could probably be constructed.
Really, the issue here is that if something else were substituted for "Fogbank," it would be untested in this application. For all of its secrecy, "Fogbank" is probably just some sort of polyurethane foam (my guess is that the "extremely flammable and explosive" solvent is an ether; polyols made from ethers can be combined with isocyanates to form polyurethanes). The foam is probably just as an insulator and space-filling material for the warhead components, and there are any number of products which would probably work just as well in the Trident warhead, but only one has been actually tested in a detonation of the device.
Without additional testing, the designers cannot be certain that any replacement foam they use would not affect the properties of the device, in particular the energy transfer from the fission component to the fusion component. If the designers knew how to make "Fogbank" again, they would have a direct like-for-like replacement. If they have to develop something new, they will probably spend a lot of time and money bombarding it with neutrons and X-rays to validate its properties.
Oh, most definitely- it's still an off-label use of the drug in the US, but people are certainly taking beta-blockers to treat performance anxiety, as well as to prevent nervous fine motor tics. At the most recent Summer Olympics, one of the medalists in pistol shooting had his medals taken away after testing positive for propranolol.
Nope, propofol (2,6-diisopropyl phenol) likely works by increasing the response to inhibitory neurotransmitters, and acts as an anesthetic. Propanolol is a non-selective beta-blocker, which blocks the beta-adrenergic receptors (receptors for epinephrine and norepinephrine). As the summary notes, the most common pharmaceutical use for this is to lower blood pressure, which it does by preventing the release of renin. Its effects on memory are completely coincidental to those on blood pressure.
In the brain, a part of the brainstem known as the locus ceruleus is the site of norepinephrine synthesis, and it is activated by stress to send norepinephrine to the amygdalae, the brain's "emotional memory association" centers. It is in the amygdalae that memories are associated with emotions, with the ultimate result being that it is easier to form long term memories of experiences that associated with strong emotions. In blocking norepinephrine transmission to the amygdala, beta-blockers most likely are acting to uncouple the connection between a stressor and its associated memory, such that the brain no longer considers it important enough to keep in long term memory.
It should be noted that the liver cells used in this device are most certainly cancer cells- the HepG2/C3A line was originally grown from a hepatocellular carcinoma cell taken out of a 15-year old boy. You can buy some here in fact.
Use of these cancer cells in an artificial liver does create the risk of transfer to the patient, but the cells in question will be suspended in a collagen matrix, and is kept separate from the blood by a dialysis-type semipermeable membrane. Contracting cancer from this device requires that the dialysis membrane fail, that cancer cells get out of the collagen and into the filtrate, that the cancer cells are not caught by the dual membrane cell filter, and that once in the body, a cancer cell from a line noted for low tumorigenic potential implants somewhere and begins to form a tumor. Not impossible, but it is unlikely.
No bacterium is an island, entire of itself; every bacterium is a piece of the intestine, a part of the main. If a Lactobacillus be washed away by the sea, the colon is the less, as well as if an Escherichia were, as well as if a colony of thy friend's or of thine own were: any bacterium's death diminishes me, because I am involved in the gut biota, and therefore never send to know for whom the bell tolls; it tolls for thee.
Well, yes, it is true that Muhammad Ali is not "punch drunk," and that his condition is classified as a movement disorder, as opposed a form of dementia (though parkinsonism may include neurological deficits as secondary symptoms). Whether or not Muhammad Ali's parkinsonism is related to his boxing career is an open, but probably unanswerable question, however. I keep using the term "parkinsonism" rather than "Parkinson's" because "Parkinson's Disease" is preferred for cases of unknown origin (with a presumable genetic cause), while "parkinsonism" or "Parkinson's Syndrome" more generally refers to the suite of symptoms that are associated with the disorder.
It's a subtle distinction, but the issue is that there are known environmental causes of the disorder. Parkinsonism simply refers to the collection of symptoms that result from damage to dopaminergic neurons of the substantia nigra. Similarly to the way that Alzheimer's damage is connected to buildup of beta-amyloid and tau proteins, Parkinson's Disease can manifest from an improper buildup of alpha-synuclein, a gradual process that can become more likely if genes related to alpha-synuclein synthesis, or to protein transport and disposal are mutant.
However, if you were to directly damage the dopaminergic neurons of the substantia nigra, you would manifest the same symptoms as a Parkinson's Disease patient. Exposure to the paraquat family of herbicides damages those neurons, as can the chemical MPTP, for example. There is evidence that damage from reactive oxygen species like hydroxyl radicals, superoxides, and peroxides can also kill these neurons; reactive oxygen species are released in traumatic brain injury, and persons who have suffered a traumatic brain injury are known to be several times more like to eventually develop parkinsonism. Tracing back to Ali, it may well have been a genetic factor he has carried his whole life that has led to his symptoms, but the effect of his long boxing career cannot be definitively ruled out.
You may watch Sr. Montalban extol the virtues of the Chrysler Cordoba here. Note that in the original commercial, Corinthian leather was "soft," not "rich."
No, this technique isn't anything like magnetoencephalography. The only way it could scan your brain is if you allowed them to cut out a cell at a time. Medical scale MRI works by aligning the spins of certain nuclei (usually hydrogen atoms, which are mostly bound in water molecules in your body) using a powerful magnetic field, then using a radiofrequency field to flip those spins, and then measuring the magnetic fields produced by the nuclei as they relax to their equilibrium state. Functional MRI, or fMRI, the type often used in brain activity monitoring, measures the differing magnetic properties of hemoglobin has when oxygen is bound versus free. Therefore, the technique monitors areas of increased oxygen usage by regions of the brain, which generally correlate to increase activity.
The technique the article discusses, however, is not to measure the magnetic properties of a bunch of atoms, but to make a picture of a sample by scanning atom by atom. A very precisely constructed magnetic needle scans over a surface, in this case, the surface of a virus. Whenever the needle hovers over a hydrogen nucleus, the nucleus flips, generating a tiny force that pushes down on the stage the virus is mounted on. By recording each of these events, a map is generated of all of the hydrogen nuclei the needle passed over. It's a great way to look at protein structure, but an awfully slow way to look at a brain.
What it amounts to is an atomic force microscope combined with a magnetic needle that allows it to perform proton NMR. An AFM is a pretty general and adaptable technique- the key element is the cantilever system that allows you to detect a tiny amount of force exerted on atoms in a sample; how you supply that force, via magnetic resonance, van der Waals forces, the Casimir effect, etc., makes it versatile. The significant drawback of this instrument is that it is a supermicroscope, not a macroscale scanner like a medical MRI machine. Samples are usually limited to a surface area of a few hundred square microns. The resolution achieved here is impressive, but is best understood as an advancement in microscopy. Just as with a light microscope or an electron microscope, this is a technique for scanning cells, not bodies.
Think of it this way- if your protein-coding genes are the blueprints for a car, then epigenetics are the blueprints, operating procedures, and logistics for a mass production automobile factory. By reading your genes, you can find out the kinds of proteins that make you up. Similarly, car blueprints tell you how to make a car. A car, just one car. However, your cells are not putting out handbuilt cars. It's a modern Toyota factory going on in there, with continuous production and assembly. It's a marvel of mass production, with transcription, splicing, translation, post-translational modification, and relocation to the site of use all going on in multiple sites constantly. Production has to be carefully coordinated to make sure you have the right amounts of the right proteins delivered at the right times.
Epigenetics is the guy at the factory who knows how many cars to build this month, and the guy who makes sure that 10,000 cars have 10,000 steering wheels available to put in. Epigenetics is the guy who tells the line to hold up on building doors, because there's a surplus of doors in the warehouse already and we should use those first. Epigenetics is not the stuff you are made of, but rather a system of production control of that stuff.
The NY Times had an interesting story last week about creatures that dine on blood.
Apparently, most obligate hematophages tend to be very small- insects and such, because blood is not an ideal source of nutrition. In particular, blood has almost no dietary fat, so a large hematophage like a vampire bat, "must consume the equivalent of half their one-ounce body weight in blood every night or risk starving to death."
Also, apparently blood is about 95% water, and so to keep from gaining too much water weight, vampire bats "urinate freely as they feed." That's a detail that seems to be missing from most vampire movies.
Long-distance migratory birds can stock up for flights by putting on fat roughly up to their lean weight, so a 630g godwit may only weigh about 315g at the end of its migration. Roughly, you're looking at about 2500kcals burned during the eight day flight, which is astonishing for an animal with about 1% of the weight of a human. This is about 0.0036kcal/second, or approximately 15 watts. Elite human athletes can produce about 6 watts per kg of body mass, while this bird can sustain 30 watts/kg for over a week.
Looking deeper into it, I should note that the specific bacteria cited here, Thermotoga maritima, are not the sort to be found on the roots of legumes. Apparently, "The Future of Things" condensed two separate discoveries into one story. The NC State work is more about identifying hydrogen-producing bacteria, while the Agricultural Research Service work is about building on the NC State work to find suitable hydrogen-producing candidates in agriculturally significant bacteria, and then decoupling hydrogen reuptake to make hydrogen collection feasible. The thermotogales that the NC State professor cited is interested in are most definitely not agriculturally significant.
Thermotogales are hyperthermophiles that live in places like hot springs, oceanic thermal vents, and the bottoms of oil wells. The processes involved are completely different- thermotogale bacteria are not nitrogen-fixers. They produce hydrogen as part of their basic metabolism. Humans, for example, produce water in their metabolism. We use oxygen as our terminal electron acceptor, so the oxygen we breathe and send to our cells gains some electrons, then quickly picks up some protons to form water. Thermotogales, however, live in an enviromnent with little oxygen, but lots of sulfur. They use sulfur as a terminal electron acceptor, and so produce hydrogen sulfide, H2S. If the available sulfur happens to be in a bound form, however, instead of producing hydrogen sulfide, they will produce lots and lots of hydrogen gas. Unfortunately, thermotogales are not very tolerant of oxygen and prefer to live in near-boiling water, so while there has been investigation into their industrial use, their suitability is far less than that of the common nitrogen-fixers.
In contrast, rhizobial bacteria have a mutual arrangement in place with legumes that make them far more hardy. Most legumes grow nodules on their roots to serve as homes for nitrogen-fixing bacteria. The enzyme-catalyzed nitrogen fixation is ruined by oxygen, so the nodule provides an anoxic environment. The legume also provides a carbon source for the bacteria. In exchange, the bacteria provide bioavailable nitrogen compounds to the legume. So, while the rate of hydrogen production is less from nitrogen-fixers, the advantages of the symbiotic arrangement are such that if you wanted to make a biotech hydrogen generation facility, a greenhouse full of bean plants might be the way to go.
Slashdot Mirror
Apparently what was going on was that Belousov was trying to generate an inorganic analog to the Krebs cycle at the time he discovered his oscillating reaction. Instead of using enzymes, he was using oxidizing agents like potassium bromate and cerium(IV)sulfate to try to interconvert a series of carboxylic acids.
Yes, oscillating chemical reactions work just like a damped harmonic oscillator system. Two (or more) competing reactions keep pushing the system back and forth through equilibrium. Unless outside energy is being pumped into the system, over time, this reaction will slow down and eventually reach equilibrium. Just as with a thermodynamic heat engine, the competing reactions in an oscillating system like the B-Z reaction cannot cycle with 100% efficiency. With each stroke of the reaction engine, energy will be lost as waste heat, and eventually the reactions involved will be unable to surmount the activation energy barriers.
Utterly believable.
ME TOO!
I mean, it had to be said, right? Right?
Well, Perftoran and the other perfluorocarbon based oxygen carriers have their own drawbacks, many of which have to do directly with their non-biological nature. In particular, pure perfluorocarbons are not soluble in blood, so they must be formulated as emulsions of tiny PFC globules emulsified by egg phosphatide protein. Even with emulsion, most PFCs are much denser than water, and tend to settle out over time. these globules are too large, the body's immune system will attack them. Perfluorocarbons also cannot be metabolized like proteins. In some respects, this is an advantage over hemoglobin-analogs, which have toxic metabolic wastes, but PFC accumulation could present a serious problem with long-term administration.
Also, storage has proven to be an issue with perfluorocarbon formulations. PFC can be stable several years if kept frozen; it must be thawed before use. While the shelf-life is atractive, the storage requirements make it difficult to use as an emergency blood alternative. There is still a place for PFC-based blood substitutes; indeed, they've proven useful in preserving organs for transplant. Their drawbacks, however, suggest there is also a place for heme-based oxygen carrier therapeutics.
You would not need to solve the protein folding problem in order to crack this form of cryptography. It is not as though data is encoded in protein conformation using this technique. In fact, this technique would be unlikely to generate well-formed proteins at all. According to the paper, the method does not actually use real nucleic acids or proteins, or even very accurately simulate their properties in biological transcription or translation. The paper is even titled "A Pseudo DNA Cryptography Method." The author is using transcription and translation as a model for the general data flow present in this scheme, but the author points out that strictly hewing to the biological splicing scheme would introduce extra vulnerabilities, since it would be possible to identify from the final protein sequence places where splicing occured.
On the subject of vulnerabilities, this method, as admitted in the paper, is a symmetric substitution cipher. You still need a secure channel to perform key exchange (the key here contains the locations and lengths of spliced out introns). If an eavesdropper gets ahold of the protein (ciphertext), a simple lookup of codons gets the eavesdropper back to the post-spliced RNA. The unique challenge of this cipher is to determine where splicing occured in order to get back to the pre-spliced RNA (which is a simple complement of the DNA sequence, which in turn is an easy substitution cipher away from the plaintext). While a clever way to implement it, the intron splicing in this method is really no different than the mechanisms used to confuse plaintexts in block ciphers like DES, and it is subject to the same vulnerabilities like differential attack.
Wow, I just found out my brain is past its prime, and now I'm being called a "loser." This just hasn't been my day at all.
As a 27-year old, I realize that I have completely spent the peak years of my intellectual capacity having made no greater contribution to the advancement of the human race than a few hundred Slashdot posts....
Yeah, I can live with that.
Locally (to the individual atoms, for example) a Mobius molecule is double-sided. Each carbon atom is fixed in a plane in graphene, though the point here is that the plane is interestingly warped. A chlorine atom could attack a carbon atom from above the plane and a bromine atom could attack from below the plane, and that would be a physically meaningful description. "Above" and "below" are of course arbitrary distinctions; let's use "a" and "b" in this post. From the perspective of Carbon #1 of the 150 carbon atoms in this molecule, the situation is nothing special; there's a bit more bond strain from the way the lattice is twisted, but it still generally behaves like a carbon atom.
What makes a Mobius molecule interesting is when you something else along its surface. For example, kinesin is a protein that works like a set of molecular legs. Picture a regular, non-Mobius single-walled carbon nanotube, a rolled-up sheet of graphene. This tube has an exterior surface (the "a" position)and an interior surface ("b")- it is two sided. To get a kinesin molecule from the exterior surface to the interior surface or vice versa, you must either cut through the graphene lattice or walk to an edge of the cylinder and flip around. There is not a smooth, continuous path from position Carbon #1-a to #1-b for a regular nanotube.
However, for a Mobius nanostrip, that added half-twist makes the "exterior surface" continuous with the "interior surface," making a smooth path possible. If you place kinesin at Carbon #1-a and have it walk around the strip, halfway through the course (for a strip with one half-twist), the kinesin will be at Carbon #1-b (in other words, back at Carbon #1, but in a local sense, on the other side of the sheet), and its orientation will be flipped 180 degrees from the original. If the kinesin keeps going, eventually it returns to its original orientation at Carbon #1-a. If you put a kinesin molecule at both 1-a and 1-b and sent them off walking in opposite directions, they would eventually collide.
Locally, 1-a is on the opposite side of 1-b, but a kinesin molecule can smoothly and continuously walk from 1-a to 1-b (or any other point) without breaking bonds in the graphene lattice or flipping around an edge to another side. Therefore, in terms of its entire shape, a Mobius molecule is one-sided.
I think you could make a molecular Klein bottle, though of course you would have the same limitation as for any Klein bottle immersed in three dimensions- a self-intersection would be necessary. This would probably rule out a physically realizable Klein bottle made purely out of graphene, as a self-intersection would either involve carbon atoms bonding to 5 or 6 other carbon atoms (extraordinarily unlikely) or bonds with significant angle strain and steric hindrance if you tried to squeeze the self-intersecting tube through the lattice instead of bonding to it. If you didn't mind including some higher-valent atoms rather than just carbon, it could probably be constructed.
Really, the issue here is that if something else were substituted for "Fogbank," it would be untested in this application. For all of its secrecy, "Fogbank" is probably just some sort of polyurethane foam (my guess is that the "extremely flammable and explosive" solvent is an ether; polyols made from ethers can be combined with isocyanates to form polyurethanes). The foam is probably just as an insulator and space-filling material for the warhead components, and there are any number of products which would probably work just as well in the Trident warhead, but only one has been actually tested in a detonation of the device.
Without additional testing, the designers cannot be certain that any replacement foam they use would not affect the properties of the device, in particular the energy transfer from the fission component to the fusion component. If the designers knew how to make "Fogbank" again, they would have a direct like-for-like replacement. If they have to develop something new, they will probably spend a lot of time and money bombarding it with neutrons and X-rays to validate its properties.
Speaking of which, what does this mean for the Toronto Raptors?
Oh, most definitely- it's still an off-label use of the drug in the US, but people are certainly taking beta-blockers to treat performance anxiety, as well as to prevent nervous fine motor tics. At the most recent Summer Olympics, one of the medalists in pistol shooting had his medals taken away after testing positive for propranolol.
A trial for that purpose is currently underway.
Nope, propofol (2,6-diisopropyl phenol) likely works by increasing the response to inhibitory neurotransmitters, and acts as an anesthetic. Propanolol is a non-selective beta-blocker, which blocks the beta-adrenergic receptors (receptors for epinephrine and norepinephrine). As the summary notes, the most common pharmaceutical use for this is to lower blood pressure, which it does by preventing the release of renin. Its effects on memory are completely coincidental to those on blood pressure.
In the brain, a part of the brainstem known as the locus ceruleus is the site of norepinephrine synthesis, and it is activated by stress to send norepinephrine to the amygdalae, the brain's "emotional memory association" centers. It is in the amygdalae that memories are associated with emotions, with the ultimate result being that it is easier to form long term memories of experiences that associated with strong emotions. In blocking norepinephrine transmission to the amygdala, beta-blockers most likely are acting to uncouple the connection between a stressor and its associated memory, such that the brain no longer considers it important enough to keep in long term memory.
It should be noted that the liver cells used in this device are most certainly cancer cells- the HepG2/C3A line was originally grown from a hepatocellular carcinoma cell taken out of a 15-year old boy. You can buy some here in fact.
Use of these cancer cells in an artificial liver does create the risk of transfer to the patient, but the cells in question will be suspended in a collagen matrix, and is kept separate from the blood by a dialysis-type semipermeable membrane. Contracting cancer from this device requires that the dialysis membrane fail, that cancer cells get out of the collagen and into the filtrate, that the cancer cells are not caught by the dual membrane cell filter, and that once in the body, a cancer cell from a line noted for low tumorigenic potential implants somewhere and begins to form a tumor. Not impossible, but it is unlikely.
No bacterium is an island, entire of itself; every bacterium is a piece of the intestine, a part of the main. If a Lactobacillus be washed away by the sea, the colon is the less, as well as if an Escherichia were, as well as if a colony of thy friend's or of thine own were: any bacterium's death diminishes me, because I am involved in the gut biota, and therefore never send to know for whom the bell tolls; it tolls for thee.
Well, yes, it is true that Muhammad Ali is not "punch drunk," and that his condition is classified as a movement disorder, as opposed a form of dementia (though parkinsonism may include neurological deficits as secondary symptoms). Whether or not Muhammad Ali's parkinsonism is related to his boxing career is an open, but probably unanswerable question, however. I keep using the term "parkinsonism" rather than "Parkinson's" because "Parkinson's Disease" is preferred for cases of unknown origin (with a presumable genetic cause), while "parkinsonism" or "Parkinson's Syndrome" more generally refers to the suite of symptoms that are associated with the disorder.
It's a subtle distinction, but the issue is that there are known environmental causes of the disorder. Parkinsonism simply refers to the collection of symptoms that result from damage to dopaminergic neurons of the substantia nigra. Similarly to the way that Alzheimer's damage is connected to buildup of beta-amyloid and tau proteins, Parkinson's Disease can manifest from an improper buildup of alpha-synuclein, a gradual process that can become more likely if genes related to alpha-synuclein synthesis, or to protein transport and disposal are mutant.
However, if you were to directly damage the dopaminergic neurons of the substantia nigra, you would manifest the same symptoms as a Parkinson's Disease patient. Exposure to the paraquat family of herbicides damages those neurons, as can the chemical MPTP, for example. There is evidence that damage from reactive oxygen species like hydroxyl radicals, superoxides, and peroxides can also kill these neurons; reactive oxygen species are released in traumatic brain injury, and persons who have suffered a traumatic brain injury are known to be several times more like to eventually develop parkinsonism. Tracing back to Ali, it may well have been a genetic factor he has carried his whole life that has led to his symptoms, but the effect of his long boxing career cannot be definitively ruled out.
You may watch Sr. Montalban extol the virtues of the Chrysler Cordoba here. Note that in the original commercial, Corinthian leather was "soft," not "rich."
No, this technique isn't anything like magnetoencephalography. The only way it could scan your brain is if you allowed them to cut out a cell at a time. Medical scale MRI works by aligning the spins of certain nuclei (usually hydrogen atoms, which are mostly bound in water molecules in your body) using a powerful magnetic field, then using a radiofrequency field to flip those spins, and then measuring the magnetic fields produced by the nuclei as they relax to their equilibrium state. Functional MRI, or fMRI, the type often used in brain activity monitoring, measures the differing magnetic properties of hemoglobin has when oxygen is bound versus free. Therefore, the technique monitors areas of increased oxygen usage by regions of the brain, which generally correlate to increase activity.
The technique the article discusses, however, is not to measure the magnetic properties of a bunch of atoms, but to make a picture of a sample by scanning atom by atom. A very precisely constructed magnetic needle scans over a surface, in this case, the surface of a virus. Whenever the needle hovers over a hydrogen nucleus, the nucleus flips, generating a tiny force that pushes down on the stage the virus is mounted on. By recording each of these events, a map is generated of all of the hydrogen nuclei the needle passed over. It's a great way to look at protein structure, but an awfully slow way to look at a brain.
What it amounts to is an atomic force microscope combined with a magnetic needle that allows it to perform proton NMR. An AFM is a pretty general and adaptable technique- the key element is the cantilever system that allows you to detect a tiny amount of force exerted on atoms in a sample; how you supply that force, via magnetic resonance, van der Waals forces, the Casimir effect, etc., makes it versatile. The significant drawback of this instrument is that it is a supermicroscope, not a macroscale scanner like a medical MRI machine. Samples are usually limited to a surface area of a few hundred square microns. The resolution achieved here is impressive, but is best understood as an advancement in microscopy. Just as with a light microscope or an electron microscope, this is a technique for scanning cells, not bodies.
Think of it this way- if your protein-coding genes are the blueprints for a car, then epigenetics are the blueprints, operating procedures, and logistics for a mass production automobile factory. By reading your genes, you can find out the kinds of proteins that make you up. Similarly, car blueprints tell you how to make a car. A car, just one car. However, your cells are not putting out handbuilt cars. It's a modern Toyota factory going on in there, with continuous production and assembly. It's a marvel of mass production, with transcription, splicing, translation, post-translational modification, and relocation to the site of use all going on in multiple sites constantly. Production has to be carefully coordinated to make sure you have the right amounts of the right proteins delivered at the right times.
Epigenetics is the guy at the factory who knows how many cars to build this month, and the guy who makes sure that 10,000 cars have 10,000 steering wheels available to put in. Epigenetics is the guy who tells the line to hold up on building doors, because there's a surplus of doors in the warehouse already and we should use those first. Epigenetics is not the stuff you are made of, but rather a system of production control of that stuff.
The NY Times had an interesting story last week about creatures that dine on blood.
Apparently, most obligate hematophages tend to be very small- insects and such, because blood is not an ideal source of nutrition. In particular, blood has almost no dietary fat, so a large hematophage like a vampire bat, "must consume the equivalent of half their one-ounce body weight in blood every night or risk starving to death."
Also, apparently blood is about 95% water, and so to keep from gaining too much water weight, vampire bats "urinate freely as they feed." That's a detail that seems to be missing from most vampire movies.
Long-distance migratory birds can stock up for flights by putting on fat roughly up to their lean weight, so a 630g godwit may only weigh about 315g at the end of its migration. Roughly, you're looking at about 2500kcals burned during the eight day flight, which is astonishing for an animal with about 1% of the weight of a human. This is about 0.0036kcal/second, or approximately 15 watts. Elite human athletes can produce about 6 watts per kg of body mass, while this bird can sustain 30 watts/kg for over a week.
Looking deeper into it, I should note that the specific bacteria cited here, Thermotoga maritima, are not the sort to be found on the roots of legumes. Apparently, "The Future of Things" condensed two separate discoveries into one story. The NC State work is more about identifying hydrogen-producing bacteria, while the Agricultural Research Service work is about building on the NC State work to find suitable hydrogen-producing candidates in agriculturally significant bacteria, and then decoupling hydrogen reuptake to make hydrogen collection feasible. The thermotogales that the NC State professor cited is interested in are most definitely not agriculturally significant.
Thermotogales are hyperthermophiles that live in places like hot springs, oceanic thermal vents, and the bottoms of oil wells. The processes involved are completely different- thermotogale bacteria are not nitrogen-fixers. They produce hydrogen as part of their basic metabolism. Humans, for example, produce water in their metabolism. We use oxygen as our terminal electron acceptor, so the oxygen we breathe and send to our cells gains some electrons, then quickly picks up some protons to form water. Thermotogales, however, live in an enviromnent with little oxygen, but lots of sulfur. They use sulfur as a terminal electron acceptor, and so produce hydrogen sulfide, H2S. If the available sulfur happens to be in a bound form, however, instead of producing hydrogen sulfide, they will produce lots and lots of hydrogen gas. Unfortunately, thermotogales are not very tolerant of oxygen and prefer to live in near-boiling water, so while there has been investigation into their industrial use, their suitability is far less than that of the common nitrogen-fixers.
In contrast, rhizobial bacteria have a mutual arrangement in place with legumes that make them far more hardy. Most legumes grow nodules on their roots to serve as homes for nitrogen-fixing bacteria. The enzyme-catalyzed nitrogen fixation is ruined by oxygen, so the nodule provides an anoxic environment. The legume also provides a carbon source for the bacteria. In exchange, the bacteria provide bioavailable nitrogen compounds to the legume. So, while the rate of hydrogen production is less from nitrogen-fixers, the advantages of the symbiotic arrangement are such that if you wanted to make a biotech hydrogen generation facility, a greenhouse full of bean plants might be the way to go.