May142014

jtotheizzoe:

The celestial maps of Su Song, Chinese polymath of the Song dynasty, the oldest known star charts in existence, dating from 1092 AD.

Previously: See how the Greeks and the Chinese viewed the same sky

May102014
“Romantic art in the American tradition is truly different from most forms of European Romanticism in that even in its most idealistic or visionary forms, American Romanticism never turns its back on the forms and structures of ordinary, waking, socially defined reality (unlike European surrealism, for example). Like the writing of Emerson himself, which attempts to express the most exalted visionary impulses in the very social styles and verbal tones that might be thought to be anathema to them, the greatest works of American art tensely inject vision into society, rather than treating it as an alternative to society. That, most rudimentarily, is what separates ‘Moby-Dick,’ ‘Huckleberry Finn,’ and ‘The Golden Bowl’ from ‘Remembrance of Things Past,’ ‘A Portrait of the Artist as a Young Man,’ and ‘Molloy.’ That is also why conventional narrative exposition (in fiction and film) and ‘realistic’ portraiture (in painting) can be, in American art, at the same time the most radical, experimental forms of expression. It is radical and daring that the three American works I have just named — though profound imaginative transformations of reality — present themselves as simple stories with characters and realistic events.” Ray Carney (1986)

(Source: homilius)

April272014
“I don’t mind that you think slowly but I do mind that you are publishing faster than you think.” Wolfgang Pauli, physicist, Nobel laureate (1900-1958)  (via fast-t-feasts)
7AM
thenewenlightenmentage:

Researchers Find Neural Signature for Mistake Correction
Culminating an 8 year search, scientists at the RIKEN-MIT Center for Neural Circuit Genetics captured an elusive brain signal underlying memory transfer and, in doing so, pinpointed the first neural circuit for “oops”—the precise moment when one becomes consciously aware of a self-made mistake and takes corrective action.
The findings, published in Cell, verified a 20 year old hypothesis on how brain areas communicate. In recent years, researchers have been pursuing a class of ephemeral brain signals called gamma oscillations, millisecond scale bursts of synchronized wave-like electrical activity that pass through brain tissue like ripples on a pond. In 1993, German scientist Wolf Singer proposed that gamma waves enable binding of memory associations. For example, in a process called working memory, animals store and recall short-term memory associations when exploring the environment.
Continue Reading

thenewenlightenmentage:

Researchers Find Neural Signature for Mistake Correction

Culminating an 8 year search, scientists at the RIKEN-MIT Center for Neural Circuit Genetics captured an elusive brain signal underlying memory transfer and, in doing so, pinpointed the first neural circuit for “oops”—the precise moment when one becomes consciously aware of a self-made mistake and takes corrective action.

The findings, published in Cell, verified a 20 year old hypothesis on how brain areas communicate. In recent years, researchers have been pursuing a class of ephemeral brain signals called gamma oscillations, millisecond scale bursts of synchronized wave-like electrical activity that pass through brain tissue like ripples on a pond. In 1993, German scientist Wolf Singer proposed that gamma waves enable binding of memory associations. For example, in a process called working memory, animals store and recall short-term memory associations when exploring the environment.

Continue Reading

7AM

science-junkie:

Blood of world’s oldest woman hints at limits of life

Death is the one certainty in life – a pioneering analysis of blood from one of the world’s oldest and healthiest women has given clues to why it happens.

Born in 1890, Hendrikje van Andel-Schipper was at one point the oldest woman in the world. She was also remarkable for her health, with crystal-clear cognition until she was close to death, and a blood circulatory system free of disease. When she died in 2005, she bequeathed her body to science, with the full support of her living relatives that any outcomes of scientific analysis – as well as her name – be made public.

Researchers have now examined her blood and other tissues to see how they were affected by age.

What they found suggests, as we could perhaps expect, that our lifespan might ultimately be limited by the capacity for stem cells to keep replenishing tissues day in day out. Once the stem cells reach a state of exhaustion that imposes a limit on their own lifespan, they themselves gradually die out and steadily diminish the body’s capacity to keep regenerating vital tissues and cells, such as blood.

In van Andel-Schipper’s case, it seemed that in the twilight of her life, about two-thirds of the white blood cells remaining in her body at death originated from just two stem cells, implying that most or all of the blood stem cells she started life with had already burned out and died.

Read more
Image: [x]  Video: slate.com

4AM
“Ultimately, I prefer Valentinus the Gnostic, Ibn Arabi the Sufi, and Moses Cordovero the Kabbalist to Freud as an authority upon the interpretation of dreams, but I believe we must go through Freud in order to get back to what he so persuasively rejected, which in the first place was the authority or value of the dream in itself. In some respects, the dream constituted for Freud not so much what he called it, the royal road to the unconscious, but the royal road away from the unconscious, in the older, primal, indeed Gnostic sense of the original Abyss.”

Omens of Millennium: The Gnosis of Angels, Dreams, and Resurrection by Harold Bloom (Riverhead, 1996) 

http://articles.latimes.com/1996-12-15/books/bk-9293_1_harold-bloom/2

H/T R’ Miles Krassen

(via aharonium)

12AM
“Ein Sof is a place to which forgetting and oblivion pertain. Why? Because concerning all the sefirot, one can search out their reality from the depth of supernal wisdom. From there it is possible to understand one thing from another. However, concerning Ein Sof, there is no aspect anywhere to search or probe; nothing can be known of it, for it is hidden and concealed in the mystery of absolute nothingness.” David ben Judah Hehasid, Matt (1990)

(Source: themaskfromsupermario2)

April252014
jewsee-medicalstudent:

The death of a cell.
This picture is an amazing 3D illustration of apoptosis. The word “apoptosis” originates from Ancient Greek ἀπό, “away from” and πτῶσις, “falling” and it is a regulated process of cell death. 
There are two ways of cell death: necrosis and apoptosis. Necrosis is a form of traumatic cell death that results from acute cellular injury, and it usually causes inflammation, because of cell’s content released outside in the extracellular fluid. Apoptosis, on the other hand, could confer advantages during an organism’s lifecycle and it produces cell fragments called apoptotic bodies that phagocytic cells are able to engulf and quickly remove, before the cell’s content spills out onto surrounding cells, causing damage.
A cell initiates intracellular apoptotic signaling in response to a stress, which may bring about cell suicide. The binding of nuclear receptors by glucocorticoids, heat, radiation, nutrient deprivation, viral infection, hypoxia and increased intracellular calcium concentration, for example, by damage to the membrane, can all trigger the release of intracellular apoptotic signals by a damaged cell. 
Research in and around apoptosis has increased substantially since the early 1990s. In addition to its importance as a biological phenomenon, defective apoptotic processes have been implicated in an extensive variety of diseases. Excessive apoptosis causes atrophy, whereas an insufficient amount results in uncontrolled cell proliferation, such as cancer.
(Source).

jewsee-medicalstudent:

The death of a cell.

This picture is an amazing 3D illustration of apoptosis. The word “apoptosis” originates from Ancient Greek ἀπό, “away from” and πτῶσις, “falling” and it is a regulated process of cell death.

There are two ways of cell death: necrosis and apoptosis. Necrosis is a form of traumatic cell death that results from acute cellular injury, and it usually causes inflammation, because of cell’s content released outside in the extracellular fluid. Apoptosis, on the other hand, could confer advantages during an organism’s lifecycle and it produces cell fragments called apoptotic bodies that phagocytic cells are able to engulf and quickly remove, before the cell’s content spills out onto surrounding cells, causing damage.

A cell initiates intracellular apoptotic signaling in response to a stress, which may bring about cell suicide. The binding of nuclear receptors by glucocorticoids, heat, radiation, nutrient deprivation, viral infection, hypoxia and increased intracellular calcium concentration, for example, by damage to the membrane, can all trigger the release of intracellular apoptotic signals by a damaged cell. 

Research in and around apoptosis has increased substantially since the early 1990s. In addition to its importance as a biological phenomenon, defective apoptotic processes have been implicated in an extensive variety of diseases. Excessive apoptosis causes atrophy, whereas an insufficient amount results in uncontrolled cell proliferation, such as cancer.

(Source).

12AM
12AM
neuromorphogenesis:

Brain Mapping
A new map, a decade in the works, shows structures of the brain in far greater detail than ever before, providing neuroscientists with a guide to its immense complexity.
Neuroscientists have made remarkable progress in recent years toward understanding how the brain works. And in coming years, Europe’s Human Brain Project will attempt to create a computational simulation of the human brain, while the U.S. BRAIN Initiative will try to create a wide-ranging picture of brain activity. These ambitious projects will greatly benefit from a new resource: detailed and comprehensive maps of the brain’s structure and its different regions.
As part of the Human Brain Project, an international team of researchers led by German and Canadian scientists has produced a three-dimensional atlas of the brain that has 50 times the resolution of previous such maps. The atlas, which took a decade to complete, required slicing a brain into thousands of thin sections and digitally stitching them back together with the help of supercomputers. Able to show details as small as 20 micrometers, roughly the size of many human cells, it is a major step forward in understanding the brain’s three-dimensional anatomy.
To guide the brain’s digital reconstruction, researchers led by Katrin Amunts at the Jülich Research Centre in Germany initially used an MRI machine to image the postmortem brain of a 65-year-old woman. The brain was then cut into ultrathin slices. The scientists stained the sections and then imaged them one by one on a flatbed scanner. Alan Evans and his coworkers at the Montreal Neurological Institute organized the 7,404 resulting images into a data set about a terabyte in size. Slicing had bent, ripped, and torn the tissue, so Evans had to correct these defects in the images. He also aligned each one to its original position in the brain. The result is mesmerizing: a brain model that you can swim through, zooming in or out to see the arrangement of cells and tissues.
At the start of the 20th century, a German neuroanatomist named Korbinian Brodmann parceled the human cortex into nearly 50 different areas by looking at the structure and organization of sections of brain under a microscope. “That has been pretty much the reference framework that we’ve used for 100 years,” Evans says. Now he and his coworkers are redoing ­Brodmann’s work as they map the borders between brain regions. The result may show something more like 100 to 200 distinct areas, providing scientists with a far more accurate road map for studying the brain’s different functions.
“We would like to have in the future a reference brain that shows true cellular resolution,” says Amunts—about one or two micrometers, as opposed to 20. That’s a daunting goal, for several reasons. One is computational: Evans says such a map of the brain might contain several petabytes of data, which computers today can’t easily navigate in real time, though he’s optimistic that they will be able to in the future. Another problem is physical: a brain can be sliced only so thin.
Advances could come from new techniques that allow scientists to see the arrangement of cells and nerve fibers inside intact brain tissue at very high resolution. Amunts is developing one such technique, which uses polarized light to reconstruct three-­dimensional structures of nerve fibers in brain tissue. And a technique called Clarity, developed in the lab of Karl Deisseroth, a neuroscientist and bioengineer at Stanford University, allows scientists to directly see the structures of neurons and circuitry in an intact brain. The brain, like any other tissue, is usually opaque because the fats in its cells block light. Clarity melts the lipids away, replacing them with a gel-like substance that leaves other structures intact and visible. Though Clarity can be used on a whole mouse brain, the human brain is too big to be studied fully intact with the existing version of the technology. But Deisseroth says the technique can already be used on blocks of human brain tissue thousands of times larger than a thin brain section, making 3-D reconstruction easier and less error prone. And Evans says that while Clarity and polarized-light imaging currently give fantastic resolution to pieces of brain, “in the future we hope that this can be expanded to include a whole human brain.”

neuromorphogenesis:

Brain Mapping

A new map, a decade in the works, shows structures of the brain in far greater detail than ever before, providing neuroscientists with a guide to its immense complexity.

Neuroscientists have made remarkable progress in recent years toward understanding how the brain works. And in coming years, Europe’s Human Brain Project will attempt to create a computational simulation of the human brain, while the U.S. BRAIN Initiative will try to create a wide-ranging picture of brain activity. These ambitious projects will greatly benefit from a new resource: detailed and comprehensive maps of the brain’s structure and its different regions.

As part of the Human Brain Project, an international team of researchers led by German and Canadian scientists has produced a three-dimensional atlas of the brain that has 50 times the resolution of previous such maps. The atlas, which took a decade to complete, required slicing a brain into thousands of thin sections and digitally stitching them back together with the help of supercomputers. Able to show details as small as 20 micrometers, roughly the size of many human cells, it is a major step forward in understanding the brain’s three-dimensional anatomy.

To guide the brain’s digital reconstruction, researchers led by Katrin Amunts at the Jülich Research Centre in Germany initially used an MRI machine to image the postmortem brain of a 65-year-old woman. The brain was then cut into ultrathin slices. The scientists stained the sections and then imaged them one by one on a flatbed scanner. Alan Evans and his coworkers at the Montreal Neurological Institute organized the 7,404 resulting images into a data set about a terabyte in size. Slicing had bent, ripped, and torn the tissue, so Evans had to correct these defects in the images. He also aligned each one to its original position in the brain. The result is mesmerizing: a brain model that you can swim through, zooming in or out to see the arrangement of cells and tissues.

At the start of the 20th century, a German neuroanatomist named Korbinian Brodmann parceled the human cortex into nearly 50 different areas by looking at the structure and organization of sections of brain under a microscope. “That has been pretty much the reference framework that we’ve used for 100 years,” Evans says. Now he and his coworkers are redoing ­Brodmann’s work as they map the borders between brain regions. The result may show something more like 100 to 200 distinct areas, providing scientists with a far more accurate road map for studying the brain’s different functions.

“We would like to have in the future a reference brain that shows true cellular resolution,” says Amunts—about one or two micrometers, as opposed to 20. That’s a daunting goal, for several reasons. One is computational: Evans says such a map of the brain might contain several petabytes of data, which computers today can’t easily navigate in real time, though he’s optimistic that they will be able to in the future. Another problem is physical: a brain can be sliced only so thin.

Advances could come from new techniques that allow scientists to see the arrangement of cells and nerve fibers inside intact brain tissue at very high resolution. Amunts is developing one such technique, which uses polarized light to reconstruct three-­dimensional structures of nerve fibers in brain tissue. And a technique called Clarity, developed in the lab of Karl Deisseroth, a neuroscientist and bioengineer at Stanford University, allows scientists to directly see the structures of neurons and circuitry in an intact brain. The brain, like any other tissue, is usually opaque because the fats in its cells block light. Clarity melts the lipids away, replacing them with a gel-like substance that leaves other structures intact and visible. Though Clarity can be used on a whole mouse brain, the human brain is too big to be studied fully intact with the existing version of the technology. But Deisseroth says the technique can already be used on blocks of human brain tissue thousands of times larger than a thin brain section, making 3-D reconstruction easier and less error prone. And Evans says that while Clarity and polarized-light imaging currently give fantastic resolution to pieces of brain, “in the future we hope that this can be expanded to include a whole human brain.”

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