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guidoLamoto

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About guidoLamoto

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  1. You must be riding out this blizzard like me, with a lot of time on your hands. Apparently many members here are academics who insist on rigorously accurate posts and like to argue details & rhetoric rather than principles. I apologize. I should have asked if anyone could name a non-renewable resource that is in danger of depletion in the next 300 yrs. You're absolutely right about our fisheries. We already did a number on our bison, but that was intentional. It wouldn't do to have 60 million migrating, large beasts trampling our crops, not to mention feeding our rivals, every year. In regards sustainable ag, I guess I should have explicitly stated that we can't use organic, renewable N sources and continue our high yields. Lower yields would translate to lower carrying capacity, and that in turn, would lead to a die-off until population numbers matched resource availability. You gotta spell it out for some people. Between the biased editorial policy and this sort of picayunish, petty crap, I don't think I'll be back here. Thanks for the ride. It's been a slice.
  2. Do the math: Pre-WW II farming was essentially "organic"-- the best yields were 50bu/ac for corn. Today, corn belt farmers get 200bu/ac-- ain't enough cow dung and Rhizobium to produce that. US population before WW II ~130M; today it's 330M....We've been swimming hard against the current all these yrs and can't stop now or we'll get swept away. To go organic on a large scale would result in a large change in the carrying capacity necessitating a commensurate die-off. ...Any volunteers?
  3. Assuming you guys aren't just experiencing flashbacks to your days as Hippies in Haight-Ashbury, maybe you're experiencing something along the lines of "binocular rivalry" based on our difficulties in simultaneously focusing on red & blue. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3159595/ Or maybe it has something to do with the miraculous ability for the brain to fill in gaps in the data (Gestalt perception). That probably has something to do with Babe Ruth overcoming amblyopia to become arguably the best hitters of all time.
  4. https://emedicine.medscape.com/article/950587-overview#a5 Her's Disease- several possible defects in the enzyme cascade that activates glycogen phosphorylase-- results in impaired production of glucose from glycogen stores.. https://emedicine.medscape.com/article/119318-overview#a5 von Gierke Dis-- defect is in G-6-Phospahatase, so G-6-P builds up in hepatocyte and is metabolized to lactate. Lactate, in turn, competes with uric acid in kidney, so uric acid levels build up.
  5. Even more basic: consider how fortuitous it was that Gregor Mendel chose the sweet pea and paid attention to six traits that each had only a limited number of alleles and followed simple "Mendellian Inheritance" (isn't that amazing? It was called Mendellian and that was his name too!)...Had he chosen traits with more alleles or polygenic inheritance patterns, he may have never noticed the pattern and we would all have been spared the tedious experience of counting all those damn fruit flies in lab, cutting so deeply into our drinking time in college.
  6. A whole lot easier to just utilize fruit walls like they did in The Middle Ages https://www.lowtechmagazine.com/2015/12/fruit-walls-urban-farming.html
  7. "Survival of the Fittest" actually refers to reproductive fitness: the individuals that can produce more offspring that themselves survive to reproduce are the ones that have the best chance for survival (actually, that's trivially deducible.) Darwin's Theory is really a specific case of the more general role of probability in Nature; things exist this way in Nature because they're the most likely to exist. Random mutations are always occurring. Most are neutral; some are deleterious (worse) and occasionally some are immediately successful. More often than not, the neutral ones plod along in low numbers in the population until the environment changes, and then they can become beneficial ones. At that point, they will be selected and increase their numbers in the gene pool. The previously more efficient genes will then become the less efficient ones. Type II Diabetes is an interesting case illustration. Once a pound of time ago, in the jungle where calories were hard to come by, an individual who could maintain body weight on only 800 cal per day would have a decided survival advantage over those who needed 1800 cal/d. Those genes were selected and were represented by a large gene frequency in the pool....Fast forward 40,000 yrs and those descendants with the "easy keeper genes" find themselves in an environment where they can easily smother themselves in YoHos & DingDongs, and we see their BS rise to 250 and they have CAD before you know it. Those easy keepers were the ones who were insulin resistant-- good in the jungle, bad in civilization. If society collapses or Bloomberg is elected president and outlaws BigGulps, they will once again have the advantage in survival. The more varied & diverse the availability of alleles in the gene pool, the more likely a species will survive a change in the environment. It's the generalist species that survive or produce the next evolutionary stock and the specialists are usually doomed to extinction.
  8. "Efficiency" is a relative thing. If you had a race engine and wanted a few more HP, then it's more efficient to slightly modify the existing engine than to completely re-design and build a whole new engine. And when it comes to evolution, given the need for random mutations to effect major changes, it would be almost impossible to count on major revisions to make the recurrent laryngeal nerve follow a shorter course. Not to mention, when it comes to morphology, our DNA complement is more of a general, suggested plan than a rigid prescription. Many of the details are left to physical constraints of the space & stresses involved and physical demands of other genetic determinants...Cf- binding feet or skulls to effect final shape & size (as a poor, contrived analogy).
  9. A few eclectic points: Half the world's population lives within 50 miles of a sea shore. People in Manhattan live 50,000/sq mi and apparently like it that way. Some of us live 5/sq mi and think it's too crowded. Can anyone name a natural resource we are in danger of depleting in the next, say 300 yrs? As the supply of a resource dwindles, it's price goes up, so demand goes down and the resource lasts even longer. We now produce more than enough food to feed our 7.5 B people. It's estimated we waste half of it. People today only starve due to local, politically impaired distribution systems. The agronomists tell us American farmers could increase yields by 25% if they all properly installed good drain tile systems.. Food's not a problem at this point. In the "Survivalists" Forums, they often talk about the " when the SHTF" situations and how they can survive because they've taken all these precautions, put up stores and can produce much of their own food. I always point out that, before they get too full of themselves, the Amish have been living that way for centuries and are much better at it. When the EOTWAWKI (End of the World As We Know It) does occur, all those Third 'World, subsistence living types will live on as if nothing happened. Mankind is safe. Industrialized society/ urban living may come under some challenges. edited to add: It's been the fad lately to talk about "sustainable agriculture." There's a reason The Fertile Crescent ain't so fertile anymore, nor is N.Africa capable any longer of being the bread basket of Rome, or why Daniel Boone & Davy Crockett kept moving west every few yrs: "organic farming" quickly plays out the land. The only sustainable ag is modern ag using inorganic N fixed by the Haber-Bosch Process. Using manure as a soil amendment only shifts fertility from the pasture to the row crops while progressively decreasing fertility of the pasture. It doesn't increase over-all fertility and is limited by the finite efficiency of natural soil microbes.
  10. A sex linked trait is determined by gene loci on the X or Y chromosomes, whereas a sex influenced trait is one whose basic loci are not on the sex chromosomes but whose penetrance or expressivity is influenced by factors such as estrogenic or androgenic hormone levels. An example of a sex linked trait is color-blindness, while traits like coarseness of body hair, bone density or muscle strength is closely associated with absolute or relative levels of estrogen & androgens....It's been said that embryologically (& figuratively) speaking, we all start out as females, but those that start making enough testosterone at the right time become males.
  11. I agree, it's a poorly conceived question, unless there really are two populations of yeast with identical loci & associated alleles, but loci & chromosome numbers arranged differently. Then it would be a matter illustrating the difficulty of defining "species." If the two populations indeed had all the same loci & alleles, then they would be phenotypically/biochemically the same, although with differing chromosome numbers, they couldn't interbreed without producing some confusing polyploidy. edited to add: Reproductive isolation is the first step on the road to speciation. OTOH- as one who sees the veracity of The Gaia Hypothesis, to me, it doesn't make any difference one way or the other
  12. Mechanism may unclear on the details at the specific biomolecular/genetic level, but in general we can say it has to do with recruitment/inhibition of genes &/or certain enzymes. For example, Cushing's Dis (excess cortisol) pts characteristically show loss of fat stores in the limbs and increase in fat stores in the cheeks and torso (centripetal obesity & moon face). Physiol. stress increase epinephrine levels which in turn influence glucagon & insulin levels which in turn influence glucose & fat metabolism.
  13. You've brought up several good points in your last several posts. Nutritional studies, thanks to those inconvenient ethics rules, won't allow us to do real controlled experiments anymore. (I'm sure this is why our prisons are so overcrowded now-- they can't volunteer as guinea pigs anymore to shorten their sentences.) Most studies rely on questionnaires and the reliability of subjects' memories: "How much smoked meat did you consume everyday from June of1982 - Sept of1996?" as if they could remember and never changed their diets. Other studies with more closely prescribed diets are short term (that's how finding works) and often show any changes occurring over the first few months return to baseline levels after one year-- ?compensatory mechanism as you suggest? You bring up a good point about some studies showing chol levels actually rising on low carb diets--I don't think it's been studied, but could physiological stress cause chlo levels to go up-- like wbc, sed rate, ferritin levels etc?..That would explain the small but definite risk of CAD vs chol levels--- oxidative or mechanical stress on the intima causes "cracks" which then recruit the healing response (fibrinogen-fibrin-WBCs, coagulation cascade and chol incorporated into the "scar?"....Hi chol may be the result, not the cause of arteriosclerosis. After 45 yrs of medical practice, I'm thoroughly convinced the leading cause of HTN is worrying about your chol level.
  14. Exactly. Sugar cane & sugar beets make equal parts of fructose and glucose and combine them to make sucrose ("table sugar"), while corn makes 55% fructose and 45% glucose and doesn't combine them into a disaccharide. It's economically advantageous for may manufacturers to use the corn sugar compared to sucrose. We quickly turn sucrose into 50% glucose/50% fructose. Hexose isomerase facilitates the conversion of fructose to glucose intracellularly. It doesn't even require an energy of activation and can be considered a spontaneous reaction. Where we put on additional fat stores is influenced to a great deal by hormones/genetics. Those who tend to have increased lipogenesis/ increased storage of fat in the pre-abdominal area tend to be the ones with Metabolic Syndrome (elevated chol, decreased insulin sensitivity, abd obesity, increased risk of CAD) so it's difficult to say that specifically fructose contributes to that or merely the total carb load.
  15. Here's how it actually works: First, there's a difference between pain (simple spinal reflex arc) vs suffering (conscious/subconscious (?) acknowledgement and reaction to a painful stimulus). A pain reflex (stimulus-->reaction) has survival value. Step on a sharp object and quickly be able to withdraw may lead to improved chances of survival. Pretty obvious. The stimulus excites a receptor, which sends a message to the spinal cord, where a synapse relays the message to the appropriate nerve to elicit the appropriate response. Afferent/efferent pathways, if you wanna get technical....Touch a hot stove and you withdraw your hand so fast you may hit yourself in the chest, for example. That's the pain response....A second later, you start hopping around and screaming. That's the suffering response, after the pain stimulus message was sent not only to the spinal cord, but forwarded to the brain...That's for acute pain-- single stimulus/single response. Chronic pain involves the ongoing stimulation of nerves-- chronic arthritis or a broken bone, for example. There's the immediate reflex and then there's the cerebral message/response arc. This elicits the phenomenon of "extinction." The brain sends a message back down to the original receptors "We got the message, You can take a break now." Negative feedback. Compare it to the experience of walking into a musty basement and immediately being hit by the smell of mold. It doesn't take long for you to forget all about it as you continue your work there Just as, say, the immune system works well to help us survive, sometimes the balance between the destructive & constructive forces of the immune response is not perfectly tuned and we get auto-immune diseases, some people have an apparently genetic insufficiency of the extinction portion of the pain system. People with fibromyalgia have unusually sever and prolonged problems with pain. This is somehow related to their metabolism of neurotransmitters such as serotonin. endorphins &/or adrenergics. They often also suffer sleep problems, anxiety &/or depression-- other situations of disordered neurotransmitter levels. Positive feedback at work. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2821819/
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