linkstream2 microblog

Runs in the Family
http://www.newyorker.com/magazine/2016/03/28/the-genetics-of-schizophrenia Overview of recent results that #SCZ is due to synaptic overpruning from excessive C4 activity

QT:{{”
A magnificently simple theory began to convulse out of the results. Perhaps C4A, like the other immunological factors that Stevens had identified in synapse pruning, marks neuronal synapses destined to be eliminated during normal brain development. During the maturation of the brain, microglia recognize these factors as tags and engulf the tagged synapses. Variations in the C4A gene cause different amounts of the C4A protein to be expressed in the human brain. The overabundance of C4A protein in some people contributes to an excessively exuberant pruning of synapses—thereby decreasing the number of synapses in the brain, which would explain the well-established fact that
schizophrenic patients tended to have fewer neuronal connections. That the symptoms of schizophrenia break loose during the second and third decades of life makes sense, in retrospect: adolescence and early adulthood are periods when synaptic pruning reaches a climax in the regions of the brain that govern planning and thinking.
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The Most Powerful Movements in #Biology
http://www.americanscientist.org/issues/id.16405,y.2015,no.5,content.true,page.1,css.print/issue.aspx How nature uses the latched bow-&-arrow construct in many contexts

QT:{{”
Just like the bow and arrow example, mantis shrimp raptorial appendages contain a spring and a latch to generate extreme power amplification. Their mechanism for power amplification is just a tweak to the standard antagonistic muscle contractions that characterize most animals’ motor systems. Just like the extensor and flexor muscle pairs that extend and flex our limbs, mantis shrimp raptorial appendages use extensor muscles to swing out their hammer and flexor muscles to fold appendage segments toward the body during normal, daily activities. However, when they need to do a high-powered blow, they contract the flexor and extensor muscles simultaneously (similar to the antagonistic leg muscle contractions that we do prior to a jump). When they co-contract these muscles, the large, bulky extensor muscles compress an elastic system and tiny flexor muscles pull latch-like mineralizations of their apodemes (tendons) over a small lump inside the appendage, thus providing effective mechanical advantage over the high forces of the large extensor muscles. The result is no movement at all! The system is primed to strike as soon as the flexor muscles relax, release the latches, and permit the stored elastic energy to release over an extremely short time period to push the hammer forward with extreme power output.

“To varying degrees, this is the trick that all high-power systems use: They temporally and spatially separate slow loading and energy storage from the rapid release of energy that confers power
amplification. Trap-jaw ants release tiny latches that block their preloaded mandibles (watch a video on Patek’s research on trap-jaw ants). Two droplets slowly grow until the point at which they fuse over exceedingly short time scales to yield the power to launch a fungal ballistospore. The jellyfish’s stinger waits within a slowly pressurizing cell; a trigger hair dramatically releases the stored pressure and ejects the stinger toward its target. Thus, whether a muscle-based movement or a fluid-driven motion, the underlying mechanisms of ultrafast systems are all about power amplification.” “}}

Inflamed by @Groopman
http://www.newyorker.com/magazine/2015/11/30/inflamed #Medicine’s Burning Q: Is inflammation the root of all problems or just a correlate to them?

Manu Prakash’s Foldscope Revolution http://www.newyorker.com/magazine/2015/12/21/through-the-looking-glass-annals-of-science-carolyn-kormann Driving microscope prices so low that all can play w/ them. #CitizenScience

Humans 2.0 http://www.newyorker.com/magazine/2015/11/16/the-gene-hackers @eric_lander: “What I love: #CRISPR [can] KO every gene &
identify…the [cancer] cell’s Achilles’ heels”

QT:{{”
“What I love most about the CRISPR process is that you can take any cancer-cell line, knock out every gene, and identify every one of the cell’s Achilles’ heels,” Eric Lander, the fifty-eight-year-old director of the Broad, told me recently. Lander, who was among the leaders of the Human Genome Project, said that he had never
encountered a more promising research tool. “You can also use CRISPR to systematically study the ways that a cancer cell can escape from a treatment,” he said. “That should make it possible to build a comprehensive road map for cancer.”

Lander went on to say that each vulnerability of a tumor might be attacked by a single drug. But cancer cells elude drugs in many ways, and, to succeed, a therapy may need to block them all. That strategy has proved effective for infectious diseases like AIDS. “Remember the pessimism about H.I.V.,” he said, referring to the early years of the AIDS epidemic, when a diagnosis was essentially a death sentence. Eventually, virologists developed a series of drugs that interfere with the virus’s ability to replicate. The therapy became truly successful, however, only when those drugs, working together, could block the virus completely.
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Now I lay me down to sleep http://www.economist.com/news/science-and-technology/21674491-modern-life-has-not-changed-sleeping-patterns-much-some-believe-now-i-lay-me City dwellers #sleep 7.5 hrs. Hunter/gathers, 5.7-7.1. Electric lights not keeping us up

100-Billion-Body Problem
http://www.americanscientist.org/issues/pub/the-100-billion-body-problem Similar issues & solutions to molecular #simulation, eg GPUs & hierarchical decomposition

#NASA Adds to Evidence of Mysterious Ancient Earthworks, built in Neolithic Kazakhstan
http://www.nytimes.com/2015/11/03/science/nasa-adds-to-evidence-of-mysterious-ancient-earthworks.html Vindication for von Daniken?

#Voyagers’ Odyssey
http://www.americanscientist.org/issues/feature/2015/4/the-voyagers-odyssey 38 year trip to beyond the solar system, taking advantage of once in 175 year planetary alignment

Playing in #Traffic
http://www.americanscientist.org/issues/pub/2015/4/playing-in-trafficDescribes Braess’s paradox, how opening a road can increase congestion, at least theoretically