////////////////////YOUR INNER FISH-SHUBIN=Your Inner Fish is my favorite sort of book--an intelligent, exhilarating, and compelling scientific adventure story, one which will change forever how you understand what it means to be human.
The field of evolutionary biology is just beginning an exciting new age of discovery, and Neil Shubin's research expeditions around the world have redefined the way we now look at the origins of mammals, frogs, crocodiles, tetrapods, and sarcopterygian fish--and thus the way we look at the descent of humankind. One of Shubin's groundbreaking discoveries, only a year and a half ago, was the unearthing of a fish with elbows and a neck, a long-sought evolutionary "missing link" between creatures of the sea and land-dwellers.
My own mother was a surgeon and a comparative anatomist, and she drummed it into me, and into all of her students, that our own anatomy is unintelligible without a knowledge of its evolutionary origins and precursors. The human body becomes infinitely fascinating with such knowledge, which Shubin provides here with grace and clarity. Your Inner Fish shows us how, like the fish with elbows, we carry the whole history of evolution within our own bodies, and how the human genome links us with the rest of life on earth.
OLIVER SACKS
////////////////////////////////Deinococcus radiodurans ("strange berry that withstands radiation", formerly called Micrococcus radiodurans) is an extremophilic bacterium, and is the most radioresistant organism known. While a dose of 10 Gy is sufficient to kill a human, and a dose of 60 Gy is sufficient to kill all cells in a culture of E. coli, D. radiodurans is capable of withstanding an instantaneous dose of up to 5,000 Gy with no loss of viability, and an instantaneous dose of up to 15,000 Gy with 37% viability. It can survive heat, cold, dehydration, vacuum, and acid, and because of its resistance to more than one extreme condition, D. radiodurans is known as a polyextremophile. It has also been listed as the world's toughest bacterium in "The Guinness Book Of World Records" because of its extraordinary resistance to several extreme conditions. It has been classified as a Gram-positive bacterium.
//////////////////Threat to medicines from plant extinctions
By Paul Eccleston
Last Updated: 12:01am GMT 19/01/2008Page 1 of 3
Millions of lives could be at risk because the plants which provide the basis of more than half of all prescription drugs face extinction, a new report warns.
Yew (top), magnolia (middle) and Hoodia (bottom) all have compounds beneficial to health
The loss of plants and trees which provide natural medicines could provoke a global healthcare crisis, says Botanic Gardens Conservation International (BGCI).
Potential cures for some of the world's deadliest diseases - including currently untreatable cancer - may be lost if the problem is not checked.
In its report London-based BGCI, which links botanic gardens in 120 countries, calls for urgent action to help secure the future of health care across the world.
It says 70 per cent of all newly-developed drugs in the United States, the world's largest and wealthiest pharmaceuticals market, are derived from natural sources and despite major scientific advances, human health is still overwhelmingly dependent on the plant kingdom.
Sara Oldfield, Secretary General of BGCI, said: "We are using up a wide range of the world's natural medicines and squandering the potential to develop new remedies. And yet it is perfectly possible to prevent plant extinctions".
Scientists had predicted that biochemistry would allow most drugs to be produced synthetically in the laboratory but in many cases it has proved impossible to reproduce the beneficial compounds found in plants.
////////////////////////////////////The "Cambrian Explosion"
Although the fossil record shows that the first multicellular animals lived about 640m years ago, the diversity of species was low until about 530m years ago. At that time there was a sudden explosion of many diverse marine species, including the first appearance of molluscs, arthropods, echinoderms and vertebrates. "Sudden" here is used in the geological sense; the "explosion" occurred over a period of 10m to 30m years, which is, after all, comparable to the time taken to evolve most of the great radiations of mammals. This rapid diversification raises fascinating questions; explanations include the evolution of organisms with hard parts (which aid fossilisation), the evolutionary "discovery" of eyes, and the development of new genes that allowed parts of organisms to evolve independently.
/////////////////////////////////The target of natural selection
Evolutionists agree that natural selection usually acts on genes in organisms - individuals carrying genes that give them a reproductive or survival advantage over others will leave more descendants, gradually changing the genetic composition of a species. This is called "individual selection". But some evolutionists have proposed that selection can act at higher levels as well: on populations (group selection), or even on species themselves (species selection). The relative importance of individual versus these higher order forms of selection is a topic of lively debate.
////////////////////////////////////Natural selection versus genetic drift
Natural selection is a process that leads to the replacement of one gene by another in a predictable way. But there is also a "random" evolutionary process called genetic drift, which is the genetic equivalent of coin-tossing. Genetic drift leads to unpredictable changes in the frequencies of genes that don't make much difference to the adaptation of their carriers, and can cause evolution by changing the genetic composition of populations. Many features of DNA are said to have evolved by genetic drift. Evolutionary geneticists disagree about the importance of selection versus drift in explaining features of organisms and their DNA. All evolutionists agree that genetic drift can't explain adaptive evolution. But not all evolution is adaptive.
//////////////////////////////////SCIENCE IS FULL OF GAPS
////////////////////////////////DTH=LF JUST SNUFFS OUT=ABOS=ABOD
///////////////////////////LF HAS NO MEANING-JUST SO-JUST LIKE VISN=UPLOC
////////////////////////////////Volcano found under Antarctic ice
Active volcano may contribute to rapid glacial melt.
Quirin Schiermeier
Radar surveys from the air can image what's under the ice.Carl Robinson/British Antarctic SurveyScientists have found an active volcano beneath Antarctic ice that last erupted just 2,000 years ago. The hotspot lies beneath the Pine Island region of the West Antarctic Ice Sheet, where glaciers are retreating more quickly than elsewhere on the continent. The dramatic find might help to explain this particularly rapid loss of ice.
Although the Antarctic is often thought of as a huge, sedate expanse of snow, the continent is known to host several active volcanoes, some of which poke out of the ice. Mount Erebus, on Ross Island in the Ross Sea, is the area’s most famous active volcano and its continuous activity has been observed since the 1970s.
//////////////////////////////////Amazon rain forest destruction quickens
5:00AM Monday January 21, 2008
A single tree remains on land that was previously jungle in Mato Grosso state, Brazil. Photo / Reuters
Climate Change
Saving fuel, planet is plain sailing
Greens urge voters: Look beyond the rhetoric
Deforestation of the Amazon has accelerated, in recent months and is likely to increase this year for the first time in four years, says a senior Brazilian government scientist.
///////////////////////////Wanted: Queen Bee Seeks Harem of Male DancersBy Charles Q. Choi, Special to LiveScience
posted: 21 January 2008 10:17 am ET
Share this story
Email Honeybee queens have sex with harems of males apparently to give birth to much better dancers, research now reveals.
The better honeybees dance, the better they are at hustling for chow, scientists added.
//////////////////////////////////UNI WISN MDSN=Study: Brain connections strengthen during waking hours, weaken during sleep
MADISON - Most people know it from experience: After so many hours of being awake, your brain feels unable to absorb any more-and several hours of sleep will refresh it.
Now new research from the University of Wisconsin School of Medicine and Public Health clarifies this phenomenon, supporting the idea that sleep plays a critical role in the brain's ability to change in response to its environment. This ability, called plasticity, is at the heart of learning.
Reporting in the Jan. 20, 2008, online version of Nature Neuroscience, the UW-Madison scientists showed by several measures that synapses - nerve cell connections central to brain plasticity - were very strong when rodents had been awake and weak when they had been asleep.
The new findings reinforce the UW-Madison researchers' highly-debated hypothesis about the role of sleep. They believe that people sleep so that their synapses can downsize and prepare for a new day and the next round of learning and synaptic strengthening.
The human brain expends up to 80 percent of its energy on synaptic activity, constantly adding and strengthening connections in response to all kinds of stimulation, explains study author Chiara Cirelli, associate professor of psychiatry.
Given that each of the millions of neurons in the human brain contains thousands of synapses, this energy expenditure "is huge and can't be sustained."
"We need an off-line period, when we are not exposed to the environment, to take synapses down," Cirelli say. "We believe that's why humans and all living organisms sleep. Without sleep, the brain reaches a saturation point that taxes its energy budget, its store of supplies and its ability to learn further."
To test the theory, researchers conducted both molecular and electro-physiological studies in rats to evaluate synaptic potentiation, or strengthening, and depression, or weakening, following sleeping and waking times. In one set of experiments, they looked at brain slices to measure the number of specific receptors, or binding sites, that had moved to synapses.
"Recent research has shown that as synaptic activity increases, more of these glutamatergic receptors enter the synapse and make it bigger and stronger," explains Cirelli.
The Wisconsin group was surprised to find that rats had an almost 50 percent receptor increase after a period of wakefulness compared to rats that had been asleep.
In a second molecular experiment, the scientists examined how many of the receptors underwent phosphorylation, another indicator of synaptic potentiation. They found phosphorylation levels were much higher during waking than sleeping. The results were the same when they measured other enzymes that are typically active during synaptic potentiation.
To strengthen their case, Cirelli and colleagues also performed studies in live rats to evaluate electrical signals reflecting synaptic changes at different times. This involved stimulating one side of each rat's brain with an electrode following waking and sleeping and then measuring the "evoked response," which is similar to an EEG, on another side.
The studies again showed that, for the same levels of stimulation, responses were stronger following a long period of waking and weaker after sleep, suggesting that synapses must have grown stronger.
"Taken together, these molecular and electro-physiological measures fit nicely with the idea that our brain circuits get progressively stronger during wakefulness and that sleep helps to recalibrate them to a sustainable baseline," says Cirelli.
The theory she and collaborator Dr. Giulio Tononi, professor of psychiatry, have developed, called the synaptic homeostasis hypothesis, runs against the grain of what many scientists currently think about how sleep affects learning. The most popular notion these days, says Cirelli, is that during sleep synapses are hard at work replaying the information acquired during the previous waking hours, consolidating that information by becoming even stronger.
"That's different from what we think," she says. "We believe that learning occurs only when we are awake, and sleep's main function is to keep our brains and all its synapses lean and efficient."
////////////////////////////////////CONSCIOUSNESS=QUANTUM COHERENCE IN MICROTUBULES
////////////////////////////////quantum state reduction=collapse of wave fn
///////////////////////////HORIZON=TOTAL ISOLATION=ALONE=SENSORY DEPRIVATION
///////////////////////////////SENSRY DEPRIVN-NEAREST-KNPR-MAY1993
/////////////////////////////////////ALSO 24 HR ON CALLS=SENSORY DEPRIVN EQUIVALENT
//////////////////////////////////Minn. hospitals, clinics purge drug co. trinkets
20 shopping carts needed to haul away pens, mugs, notepads
Julia Cheng / AP
Duluth Clinic neurology department manager Gwen Cressman sorts through some of the 18,718 pens, notepads and other drug company trinkets purged from the St. Mary's Duluth Clinic health system as part of the "Clean Sweep" initiative, Friday afternoon.
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MINNEAPOLIS - When a Duluth-based operator of hospitals and clinics purged the pens, notepads, coffee mugs and other promotional trinkets drug companies had given its doctors over the years, it took 20 shopping carts to haul the loot away.
The operator, SMDC Health System, intends to ship the 18,718 items to the west African nation of Cameroon.
///////////////////////////////////SENSORY DEPRIVN CAUSES MARKED DETERIORN OF MENTAL FN PROCESSES
/////////////////////////////////////
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