Posts Tagged ‘quote’

The formation of the solar system

May 29, 2017

http://atropos.as.arizona.edu/aiz/teaching/nats102/mario/solar_system.html

QT:{{”

Initially the cloud was about several light years across. A small overdensity in the cloud caused the contraction to begin and the overdensity to grow, thus producing a faster contraction –> run away or collapse process

Initially, most of the motions of the cloud particles were random, yet the nebula had anet rotation. As collapse proceeded, the rotation speed of the cloud was gradually increasing due to conservation of angular momentum.


Gravitational collapse was much more efficient along the spin axis, so the rotating ball collapsed into thin disk with a diameter of 200 AU (0.003 light years) (twice Pluto’s orbit), aka solar nebula (movie), with most of the mass concentrated near the center.

As the cloud contracted, its gravitational potential energy was converted into kinetic energy of the individual gas particles. Collisions between particles converted this energy into heat (random motions). The solar nebula became hottest near the center where much of the mass was collected to form the protosun(the cloud of gas that became Sun).
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CATO score

May 28, 2017

Seq. variants influencing…TF occupancy
http://www.Nature.com/ng/journal/v47/n12/full/ng.3432.html Uses allelic analysis to develop the CATO score, how variants alter binding

QT:{{”
This approach resulted in a simple scoring scheme, termed contextual analysis of transcription factor occupancy (CATO), that provides a recalibrated probability of affecting the binding of any transcription factor, as well as a quantitatively ranked list of transcription factor families whose binding might be altered.
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Intersection of diverse neuronal genomes and neuropsychiatric disease: The Brain Somatic Mosaicism Network | Science

May 15, 2017

The #Brain #Somatic Mosaicism Network
http://science.ScienceMag.org/content/356/6336/eaal1641 Long lifespan of neurons accentuates impact of individual somatic mutations

QT:{{”
Neuropsychiatric disorders have a complex genetic architecture. Human genetic population-based studies have identified numerous heritable sequence and structural genomic variants associated with
susceptibility to neuropsychiatric disease. However, these germline variants do not fully account for disease risk. During brain development, progenitor cells undergo billions of cell divisions to generate the ~80 billion neurons in the brain. The failure to accurately repair DNA damage arising during replication,
transcription, and cellular metabolism amid this dramatic cellular expansion can lead to somatic mutations. Somatic mutations that alter subsets of neuronal transcriptomes and proteomes can, in turn, affect cell proliferation and survival and lead to neurodevelopmental disorders. The long life span of individual neurons and the direct relationship between neural circuits and behavior suggest that somatic mutations in small populations of neurons can significantly affect individual neurodevelopment. The Brain Somatic Mosaicism Network has been founded to study somatic mosaicism both in neurotypical human brains and in the context of complex neuropsychiatric disorders.” “}}

Bit by Bit: The Darwinian Basis of Life

May 15, 2017

Bit by Bit: The #Darwinian Basis of Life
http://www.PLoSBiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001323 Overview of the amount of generated information in replicating molecules

QT:{{”
“The number of possible compositions is xn. If these are all equally probable, then each has a prior probability of occurrence of x−n, and the information content (number of bits) associated with a particular realized composition is log2(xn). This can also be expressed as 2#bits = xn. For a binary polymer, #bits = n; for a nucleic acid polymer, #bits = 2n.

If the various compositions do not have the same prior probability of occurrence, then the information content associated with a particular realized composition must be calculated based on its prior probability of occurrence (pk), which ranges from 0 to 1. The information content (number of bits) associated with a particular realized composition is −log2(pk).”
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Gerald F. Joyce
Published: May 8, 2012
https://doi.org/10.1371/journal.pbio.1001323

Ticks on the Rise in Connecticut

May 14, 2017

http://ehs.yale.edu/sites/default/files/files/Safety-Bulletins/may2017.pdf

QT:{{”
 Avoid wooded and brushy areas with high grass and leaf litter.  Use repellents that contain 20 to 30 percent DEET on exposed skin and clothing for protection that lasts up to several hours.
 Bathe or shower as soon as possible after coming indoors to wash off and more easily find ticks.
 Conduct a full-body tick check using a hand-held or full-length mirror to view all parts of your body upon return from tick-infested areas.

Removing a Tick
 Use fine-tipped tweezers to grasp the tick as close to the skin’s surface as possible.

Never crush a tick with your fingers.
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Cell-free biotech will make for better products

May 8, 2017

Cell-free biotech will make for better products
http://www.Economist.com/news/science-and-technology/21721560-new-type-biological-engineering-should-speed-up-innovation-cell-free-biotech Gr8 screening, quickly making proteins from oligos HT @EmilyLeproust

QT:{{”
“A typical recipe for making cell-free protoplasmic gloop is this. Take four litres of culture containing E. coli (a gut bacterium favoured by genetic engineers). Split the bacterial cells open by forcing them through a tiny valve at pressure, thus shredding their membranes and DNA, and liberating the ribosomes. Incubate the resulting mixture at 37°C for an hour, to activate enzymes called exonucleases that will eat up the fragmented DNA. Centrifuge, to separate the scraps of cell membrane and other detritus from the gloop that contains ribosomes. Dialyse to remove unwanted ions. Then stir in amino acids (the building blocks of proteins), sugar and an
energy-carrying molecule called adenosine triphosphate (ATP) to power the process. Finally, add a pinch of new DNA to taste, to tell the gloop which proteins it is supposed to produce.”
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A.I. Versus M.D.

May 7, 2017

AI v MD by @DrSidMukherjee http://www.NewYorker.com/magazine/2017/04/03/ai-versus-md great progress finding skin #cancer. Eventually, continuous monitoring via iPhone pics

QT:{{"
“In June, 2015, Thrun’s team began to test what the machine had learned from the master set of images by presenting it with a “validation set”: some fourteen thousand images that had been diagnosed by dermatologists (although not necessarily by biopsy). Could the system correctly classify the images into three diagnostic categories—benign lesions, malignant lesions, and non-cancerous growths? The system got the answer right seventy-two per cent of the time. …Two board-certified dermatologists who were tested alongside did worse: they got the answer correct sixty-six per cent of the time.

“There’s one rather profound thing about the network that wasn’t fully emphasized in the paper,” Thrun told me. In the first iteration of the study, he and the team had started with a totally naïve neural network. But they found that if they began with a neural network that had already been trained to recognize some unrelated feature (dogs versus cats, say) it learned faster and better. Perhaps our brains function similarly. Those mind-numbing exercises in high school—factoring polynomials, conjugating verbs, memorizing the periodic table—were possibly the opposite: mind-sensitizing.”
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The Media Bubble is Real — And Worse Than You Think

May 1, 2017

QT:{{
“As the votes streamed in on election night, evidence that the country had further cleaved into two Americas became palpable. With few exceptions, Clinton ran the table in urban America, while Trump ran it in the ruralities. And as you might suspect, Clinton dominated where internet publishing jobs abound. Nearly 90 percent of all internet publishing employees work in a county where Clinton won, and 75 percent of them work in a county that she won by more than 30 percentage points. When you add in the shrinking number of newspaper jobs, 72 percent of all internet publishing or newspaper employees work in a county that Clinton won. By this measure, of course, Clinton was the national media’s candidate.”
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The Media Bubble is Real — And Worse Than You Think
http://politi.co/2q0ZmYh

Sarah Silverman, Mark Ruffalo and Edward Norton at Turtle Ball – NYTimes.com

May 1, 2017

At the turtle ball
https://www.NYTimes.com/2017/04/19/fashion/sarah-silverman-mark-ruffalo-edward-norton-turtle-ball.html “I relate deeply to a #turtle…1 thing I’ve learned is to just set your course & plod…through”

QT:{{”

“Mr. Ruffalo accepted his award. “I’m sure I’m not the first person to ever say this, but I relate deeply to a turtle,” he said. “I’m really an introvert even though I’m an actor. And the one thing that I’ve learned is to just set your course and slowly plod your way through it.”
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Analysis | The nation is immersed in its warmest period in recorded history

May 1, 2017

US…immersed in its warmest period in recorded history
https://www.WashingtonPost.com/news/capital-weather-gang/wp/2017/04/18/the-nation-is-immersed-in-its-warmest-period-in-recorded-history/ “Latest 1,2,3,4 & 5 yr periods rank as…warmest in 122 yrs”

QT:{{”
“The latest one-, two-, three-, four- and five year periods — ending in March — rank as the warmest in 122 years of record-keeping for the Lower 48 states, according to data from the National Oceanic and Atmospheric Administration.”
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