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General Knowledge

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News clippings

(Not in any particular order)

Sociology of science

  • Diet and Fat: A Severe Case of Mistaken Consensus BBC 17-Aug-2006
    ... An “informational cascade”... one person after another assumes that the rest can't all be wrong. Because of this effect, groups are surprisingly prone to reach mistaken conclusions even when most of the people started out knowing better... Cascades are especially common in medicine as doctors take their cues from others, leading them to overdiagnose some faddish ailments (called bandwagon diseases) and overprescribe certain treatments (like the tonsillectomies once popular for children).

Genetics

We are robot vehicles blindly programmed to preserve the selfish molecules known as genes
-- Richard Dawkins, The Selfish Gene
  • Now: The Rest of the Genome NY Times 11 Nov. 2008
    • The gene, in other words, is in an identity crisis. This crisis comes on the eve of the gene’s 100th birthday. ...
    • The 21,000 protein-coding genes in the human genome make up just 1.2 percent of that genome.
    • But it turns out that the genome is also organized in another way, one that brings into question how important genes are in heredity. Our DNA is studded with millions of proteins and other molecules, which determine which genes can produce transcripts and which cannot. New cells inherit those molecules along with DNA. In other words, heredity can flow through a second channel.
    • These discoveries left scientists wondering just how much noncoding RNA our cells make. The early results of Encode suggest the answer is a lot. Although only 1.2 percent of the human genome encodes proteins, the Encode scientists estimate that a staggering 93 percent of the genome produces RNA transcripts.
    • Only about 4 percent of the noncoding DNA in the human genome shows signs of having experienced strong natural selection. Some of those segments may encode RNA molecules that have an important job in the cell. Some of them may contain stretches of DNA that control neighboring genes. Dr. Haussler suspects that most of the rest serve no function. 
  • Entire Synthetic Genome Created Nat. Geographic 25-Jan-2008
  • In DNA Era, New Worries About Prejudice NYTimes 11-Nov-2007
    When scientists first decoded the human genome in 2000, they were quick to portray it as proof of humankind’s remarkable similarity. The DNA of any two people, they emphasized, is at least 99 percent identical.
    But new research is exploring the remaining fraction to explain differences between people of different continental origins.
  • Research finds 'unique human DNA' BBC 17-Aug-2006
    Scientists say they have discovered a gene sequence which appears to play a central role in giving humans their unique brain capacity.
    The area, called HAR1, has undergone accelerated evolutionary change in humans and is active during a critical stage in brain development.
    The analysis showed that HAR1 is essentially the same in all mammals except humans. There were just two differences between the versions found in chickens and chimps. However, there were 18 differences between the chimp version and the one found in humans - which scientists say is an incredible amount of change to take place in a few million years.
    His colleague, Dr Gerton Lunter, said: "What is really interesting is that this is a special type of gene. "It seems likely that it changes the way the brain is wired in some way."
  • Scientists Say They've Found a Code Beyond Genetics in DNA New York Times 25-Jul-2006
    Researchers believe they have found a second code in DNA in addition to the genetic code. The genetic code specifies all the proteins that a cell makes. The second code, superimposed on the first, sets the placement of the nucleosomes, miniature protein spools around which the DNA is looped. The spools both protect and control access to the DNA itself.
    The discovery, if confirmed, could open new insights into the higher order control of the genes, like the critical but still mysterious process by which each type of human cell is allowed to activate the genes it needs but cannot access the genes used by other types of cell.
  • Spotty mice flout genetics laws BBC 24-May-2006 (See also: Mouse Finding Violates Laws of Heredity Scientific American)
    In recent years researchers have amassed much circumstantial evidence to show that transmission of genes made of nuclear DNA is not the sole factor affecting inheritance.
    The scientists believe the RNA molecules pass from the sperm into the egg, and they "silence" the Kit gene activity in the offspring - even those who do not inherit a copy of the mutant gene. Silencing the activity in this gene leads to a spotted tail.
    The phenomenon whereby the characteristic of a gene is "remembered" and seen in later generations, even if that particular version of the gene is no longer present, is called paramutation.
  • Twin Data Highlight Genetic Changes. Washington Post, 5-Jul-2005 (Epigenetics)
    The new research... focused on two biological mechanisms that influence gene activity. In one, called DNA methylation, enzymes inside a cell attach a minuscule molecular decoration to a gene, deactivating that gene. In the other, called histone acetylation, a dormant gene is made active again. These altered genetic settings can last a lifetime (though they are not passed down to a person's offspring) and can be important if, say, the gene turned off is one that protects against cancer.
  • Rogue weeds defy rules of genetics. New Scientist, 26-Mar-2005 ("Backup copies", see also: New York Times)
    Mendelian inheritance, the central tenet of genetics, is under attack from a few scrawny weeds that haven't read the textbooks. The weeds are somehow inheriting DNA sequences from their grandparents that neither of their parents possessed - which is supposed to be impossible.
  • The human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence.

Genetic engineering

  • Scientists to mix cells of humans and cows Telegraph 7-Nov-2006
    Two teams of researchers yesterday submitted applications to the Human Fertilisation and Embryology Authority to carry out experiments in which human cells will be fused with rabbit, cow and goat eggs.
  • Concern over creation of new life forms Guardian 22-May-2006
    Using genetic sequences for polio obtained by mail order, the researchers built the world's first synthetic virus, prompting Dr Wimmer to warn that other viruses, such as smallpox, could similarly be made given the knowhow.
    Last year, synthetic biologists working for the US army triggered further concern by recreating the 1918 flu virus with help from genetic sequences taken from a victim frozen in the Alaskan permafrost.

Bioengineering

  • A Step Toward a Living, Learning Memory Chip Scientific American 6-May-2007
    Researchers at Tel Aviv University in Israel have demonstrated that neurons cultured outside the brain can be imprinted with multiple rudimentary memories that persist for days without interfering with or wiping out others.
    Initially, when a group of neurons is clustered in a network, merely linking them will cause a spontaneous pattern of activity. Ben-Jacob and Baruchi sought to imprint a memory by injecting a chemical suppressor into a synapse between inhibitory neurons. Their goal: to disrupt the restrictive function of those cells, essentially causing the brakes they put on the excitatory members in the network to loosen. "This is like teaching by liberation," Ben-Jacob says. "We liberate the excitatory neurons to do what they want to do."
    The pair chemically treated inhibitory neurons by injecting them with droplets of picrotoxin, an antagonist of gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the brain. The chemical suppression of the inhibitory neuron created a pattern kicked off by a neighboring excitatory neuron that was now free to fire. Other neurons in the culture began to fire one by one as they received an electrical signal from one of their neighbors. This continued in the same pattern, which repeated for over a day. This new sequence of activity coexisted with the electrical pattern that was spontaneously generated when the neural culture was initially linked.
  • Baby’s First Diet Pill New York Times 5-Oct-2004
    A new field called developmental programming maintains a third possibility: that obesity, like many aspects of our physiology, can be traced to the months just before and after birth, when the brain and other organs are still fine-tuning themselves.

(Pre-)History

  • Researchers say prehistoric man invented dental drill 9,000 years ago Discovery 6-Apr-2006
  • DNA Study Yields Clues on First Migration of Early Humans. New York Times, 13-May-2005
    The geneticists say there was only one migration of modern humans out of Africa; that it took a southern route to India, Southeast Asia and Australia; and that it consisted of a single band of hunter-gatherers, probably just a few hundred people strong. ... Everyone in the world can be placed on a single family tree, in terms of their mitochondrial DNA, because everyone has inherited that piece of DNA from a single woman, the mitochondrial Eve, who lived some 200,000 years ago.

Homo Sapiens

  • New Fossils Add Link to the Chain of the Evolution of Humans New York Times 13-Apr-2006
    The genus Ardipithecus... appears to have lived 4.4 million to 5.7 million years ago. It was even more apelike, but also walked on two legs. ... The relationship between Ardipithecus and Australopithecus, scientists said, remains unclear because of the wide gap in their chronology. Still, they suggested that one probably led to the other. ...
    The scientists said the fossils supported the hypothesis that Australopithecus Anamensis was a direct ancestor of Afarensis, which lived 3 million to 3.6 million years ago. The Australopithecus genus—resembling apes in stature and brain size but unlike the great apes in that it walked on two legs—is thought to have given rise to our own genus, Homo.
    Some later australopithecines survived until about 1.2 million years ago, existing in Africa as contemporaries with Homo erectus, a predecessor of modern humans.
  • Still Evolving, Human Genes Tell New Story. New York Times, 7-Mar-2006
    Providing the strongest evidence yet that humans are still evolving, researchers have detected some 700 regions of the human genome where genes appear to have been reshaped by natural selection, a principal force of evolution, within the last 5,000 to 15,000 years. ... Under natural selection, beneficial genes become more common in a population as their owners have more progeny.
  • Research Reveals the Changing Shape of the Human Face. University of Birmingham, 23-Jan-2006.
    Research at the University of Birmingham has shown that the shape of the human skull has changed significantly over the last 600 years. Results show that modern man has less prominent facial features and a larger cranial capacity than our medieval ancestors.

Evolution

  • Pea-Brains Make Best Prey, Study Finds Discovery 18-Aug-2006
    Predators prefer to chase smaller-brained prey, which often lack the mental fortitude to escape their brainier hunters... The findings, published in the Royal Society Journal Biology Letters, suggest brain size evolution may be driven by predator-prey relationships since, like a perpetual "Road Runner" cartoon, each side is forever trying to outwit the other.
  • Scientists Call Fish Fossil the 'Missing Link' New York Times 5-Apr-2006
    Scientists have discovered fossils of a 375 million-year-old fish, a large scaly creature ... that they say is a long-sought "missing link" in the evolution of some fishes from water to a life walking on four limbs on land... a predecessor thus of amphibians, reptiles and dinosaurs, mammals and eventually humans.
  • Did Life Come from Another World? Scientific American, 24-Oct-2005
    New research indicates that microorganisms could have survived a journey from Mars to Earth.

Biology

  • Looking for the gene(s) that can tame a wild rat Int'l Herald Tribune 26-Jul-2006
    Belyaev decided to study the genetics of domestication, a problem to which Darwin gave deep attention. Domesticated animals differ in many ways from their wild counterparts, and it has never been clear just which qualities were selected for by the Neolithic farmers who developed most major farm species about 10,000 years ago.
    One possibility is that a handful of genes - perhaps even just one - underlie all the changes seen in domestication.
  • Mirror neurons and the brain in the vat The Edge, 10-Jan-2006
    Researchers at UCLA found that cells in the human anterior cingulate, which normally fire when you poke the patient with a needle ("pain neurons"), will also fire when the patient watches another patient being poked. The mirror neurons, it would seem, dissolve the barrier between self and others. I call them "empathy neurons" or "Dalai Llama neurons". ... Dissolving the "self vs. other" barrier is the basis of many ethical systems, especially eastern philosophical and mystical traditions. This research implies that mirror neurons can be used to provide rational rather than religious grounds for ethics.
  • Unlocking the Secrets of Longevity Genes. Scientific American, 20-Feb-2005
    A handful of genes that control the body's defenses during hard times can also dramatically improve health and prolong life in diverse organisms. Understanding how they work may reveal the keys to extending human life span while banishing diseases of old age.
  • Deceit of the Raven. New York Times, 4-Sep-2005
    It began with apes. In the 1960's and 70's, scientists taught captive chimps to use words and documented wild ones using tools and planning hunting expeditions. Then other smart mammals—monkeys, elephants and porpoises among them—also proved to have surprisingly ''human'' mental powers. And in the last few years, the circle has expanded to still other mammals and beyond.

Physics

  • One Big Bang, or were there many?
    The universe is at least 986 billion years older than physicists thought and is probably much older still, according to a radical new theory.
    The Cosmological Constant is a mathematical representation of the energy of empty space, also known as "dark energy", which exerts a kind of anti-gravity force pushing galaxies apart at an accelerating rate. ... It happens to be a googol (1 followed by 100 zeroes) times smaller than would be expected if the universe was created in a single Big Bang. But its value could be explained if the universe was much, much older than most experts believe.
  • Triumph of mind over dark matter The Telegraph 26-Apr-2006
    ...the smallest possible volume of dark matter is a cube measuring 1,000 light years along each side containing 13 million times as much mass as the Sun.
    Visible matter is thought to account for only about four per cent of the mass of the Universe. The rest is believed to be made of 23 per cent dark matter and 73 per cent of "dark energy", a mysterious force causing the Universe to expand at increasing speed.
  • Inconstant constants. New Scientist, 23-May-2005
    Some things never change. Physicists call them the constants of nature. ... Meanwhile physicists have also come to appreciate that the values of many of the constants may be the result of mere happenstance, acquired during random events and elementary particle processes early in the history of the universe. In fact, string theory allows for a vast number—10500—of possible "worlds" with different self-consistent sets of laws and constants.

Mathematics

  • Elusive Proof, Elusive Prover: A New Mathematical Mystery New York Times 15-Aug-2006
    Three years ago, a Russian mathematician by the name of Grigory Perelman...announced that he had solved a famous and intractable mathematical problem, known as the Poincare's conjecture, about the nature of space.
    In a speech at a conference in Beijing this summer, Shing-Tung Yau of Harvard said the understanding of three-dimensional space brought about by Poincare's conjecture could be one of the major pillars of math in the 21st century.

History of science

  • Einstein's Legacy, Yehuda Elkana 1-Mar-2005
    Out of the myriad of themes one could choose for discussion all of which would contribute to admiration, to a love of science and research, to a dedication to freedom, democracy, international cooperation and an unprejudiced egalitarianism towards all and everybody in the whole world, I have decided to choose one central theme—that of Befreiung—and to follow in a brief survey the implications of this attitude in many walks of life, from science to politics.

Nutrition

  • The reality is that everything is made of chemicals Telegraph 8-Nov-2008
    The reality is that, despite fears that our children are "pumped full of chemicals" everything is made of chemicals, down to the proteins, hormones and genetic materials in our cells. ... Plenty of "natural chemicals" (whatever that means) are nastier than synthetic chemicals — think of alcohol or those in tobacco smoke. And all potatoes—not just the green ones—contain some poison (solanidine alkaloids).
    Whether a substance is synthetic, copied from nature or extracted directly from nature, tells us nothing much at all about the dangers it poses.
    The phobia about chemicals has been fuelled by many factors: claims about chemicals being "linked" to diseases often tell us that a chemical was present when an harmful effect occurred, rather than really showing that the chemical caused the damage.
    Prof Nigel Brown, of St George's, University of London, said: "It is possible that there is a problem, we should be aware of this and we should study the problem, but there is currently not a shred of evidence of a pandemic.
  • There is no need to cut your salt intake, say scientists. The Telegraph 29-May-2005
    Advice on reducing your sodium intake should be taken with a pinch of salt, according to the latest research. Not only is there no need to eat less of it but it can also be positively dangerous for some people's health.

Religion

  • 'Gospel of Judas' Surfaces After 1,700 Years New York Times 6-Apr-2006 [National Geographic]
    An early Christian manuscript, including the only known text of what is known as the Gospel of Judas, has surfaced after 1,700 years. The text gives new insights into the relationship of Jesus and the disciple who betrayed him...
    In this version, Jesus asked Judas, as a close friend, to sell him out to the authorities, telling Judas he will "exceed" the other disciples by doing so. ...
    The 26-page Judas text is said to be a copy in Coptic, made around A. D. 300, of the original Gospel of Judas, written in Greek the century before.
    Terry Garcia, an executive vice president of the geographic society, said the manuscript, or codex, is considered by scholars and scientists to be the most significant ancient, nonbiblical text to be found in the past 60 years.
    The Gospel of Judas is only one of many texts discovered in the last 65 years, including the gospels of Thomas, Mary Magdalene and Philip, believed to be written by Gnostics.

Medicine & pharmacology

Politics

  • Living with a superpower. The Economist, 2-Jan-2003
    Some values are held in common by America and its allies. As three studies show, many others are not.

Psychology

  • High level of male hormone in girls reveals autism clue Telegraph 10-Oct-2006
    Prof Simon Baron-Cohen and Sally Wheelwright have uncovered new evidence that testosterone and other sex hormones thought to shape sex differences may cause autism by pushing brain development beyond that of a typical male. ... They found that the CAH girls, who develop some male physical characteristics, have more autistic traits than typical females.
  • Neuromarketing: is it coming to lab near you? PBS 9-Nov-2004
    Neuromarketing [is] the study of the brain's responses to ads, brands, and the rest of the messages littering the cultural landscape. Montague had his subjects take the Pepsi Challenge while he watched their neural activity with a functional MRI machine, which tracks blood flow to different regions of the brain. Without knowing what they were drinking, about half of them said they preferred Pepsi. But once Montague told them which samples were Coke, three-fourths said that drink tasted better, and their brain activity changed too. Coke "lit up" the medial prefrontal cortex -- a part of the brain that controls higher thinking.
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On The Edge

  • The principle of mediocrity (inflation theory) Alexander Vilenkin, 15-Sep-2006
    According to the new picture, distant parts of the universe are in the state of explosive, accelerated expansion, called "inflation". The expansion is so fast that in a tiny fraction of a second a region the size of an atom is blown to dimensions much greater than the entire currently observable universe. The expansion is caused by a peculiar form of matter, called "false vacuum", which produces a strong repulsive force.
  • The Hazards of the New Online Collectivism Jaron Lanier, 30-Jun-2006
    The problem I am concerned with here is not the Wikipedia in itself. ... the problem is in the way the Wikipedia has come to be regarded and used; how it's been elevated to such importance so quickly.
    In the last year or two the trend has been to remove the scent of people, so as to come as close as possible to simulating the appearance of content emerging out of the Web as if it were speaking to us as a supernatural oracle. This is where the use of the Internet crosses the line into delusion.
  • The selfish gene: thirty years on 16-Mar-2006
    In the twentieth century, a period of great scientific advancement, instead of having science and technology at the center of the intellectual world—of having a unity in which scholarship included science and technology along with literature and art—the official culture kicked them out. Traditional humanities scholars looked at science and technology as some sort of technical special product. Elite universities nudged science out of the liberal arts undergraduate curriculum—and out of the minds of many young people, who, as the new academic establishment, so marginalized themselves that they are no longer within shouting distance of the action.
  • Mirror Neurons V.S. Ramachandran, 10-Jan-2006
    Rizzolati and Gallasse discovered mirror neurons. They found that neurons in the ventral premotor area of macaque monkeys will fire anytime a monkey performs a complex action ... but a subset of them, the Italians found, will fire even when the monkey watches another monkey perform the same action. In essence, the neuron is part of a network that allows you to see the world "from the other persons point of view," hence the name "mirror neuron."
    Now imagine ... I destroy your present brain and replace it with a replica/simulacrum with identical information. There would be no reason to believe your conscious experience would not continue in that other brain ... But if you accept this argument then why not replace your brain with five replicas in five vats instead of just one? Would you then "continue" in all five?
  • Free will is exercised unconsciously, without awareness Eric R. Kandel's answer to the question: What is your dangerous idea? 1-Jan-2006
    Libet found that the readiness potential appeared not after, but 200 milliseconds before a person felt the urge to move his or her finger! Thus by merely observing the electrical activity of the brain, Libet could predict what a person would do before the person was actually aware of having decided to do it.
    These experiments led to the radical insight that by observing another person's brain activity, one can predict what someone is going to do before he is aware that he has made the decision to do it. This finding has caused philosophers of mind to ask: If the choice is determined in the brain unconsciously before we decide to act, where is free will?
  • the purpose of life is to disperse energy: Scott Sampson's answer to the question: What is your dangerous idea? 1-Jan-2006
    Virtually all organisms, including humans, are, in a real sense, sunlight transmogrified, temporary waypoints in the flow of energy. Ecological succession, viewed from a thermodynamic perspective, is a process that maximizes the capture and degradation of energy. Similarly, the tendency for life to become more complex over the past 3.5 billion years (as well as the overall increase in biomass and organismal diversity through time) is not due simply to natural selection, as most evolutionists still argue, but also to nature's "efforts" to grab more and more of the sun's flow.
    ... Ecology has been summarized by the pithy statement, "energy flows, matter cycles." ... Moreover, evolution is not driven by the machinations of selfish genes propagating themselves through countless millennia. Rather, ecology and evolution together operate as a highly successful, extremely persistent means of reducing the gradient generated by our nearest star.
  • The mathematics of love 14-Apr-2005
  • What do you believe in and cannot prove? 1-Apr-2005
    It may be that it's okay not to be certain, but to have a hunch, and to perceive on that basis. There is also evidence here that the scientists are thinking beyond their individual fields. Yes, they are engaged in the science of their own areas of research, but more importantly they are also thinking deeply about creating new understandings about the limits of science, of seeing science not just as a question of knowing things, but as a means of tuning into the deeper questions of who we are and how we know.
  • Language, Biology, and the Mind 28-Jan-2004
    children know something even as soon as they're born: for example, they can recognize the difference between a face and a scrambled version of a face. What's been unsatisfying for me is that we haven't understood how the brain gets to be that way. How is it that we go from a fertilized egg to this complicated brain that at birth is already starting the process of language acquisition, and is already starting the problem of analyzing the world?
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Reference

Physics

Philosophy of science

  • T. Kuhn. The Structure of Scientific Revolutions [Frank Pajares, Emory U.]
  • Yehuda Elkana. "A Programmatic Attempt at an Anthropology of Knowledge." Ch. in: E. Mendelsohn, Y. Elkana, Sciences and Cultures. Sociology of the Sciences. Vol. V, pp. 1–176. D. Reidel Publishing Company, 1981. [Write me for a hard copy]

Astronomical images

Evolution

Nutrition

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