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Eye 1

Human stem cells lead to corneal regrowth, improved vision in mice

Eye
© Piotr Krzeslak/Thinkstock.com
In an exciting new study, researchers have discovered a way to collect cells for the regeneration of corneal tissue - the clear membrane covering the pupil that directs light into the back of the eye.

The research team from Boston reported that purified human stem cells were used to improve long-term vision in mice. Currently, the team is waiting for FDA-approval to begin patient clinical trials.

This collaborative research effort was led by Natasha Frank, MD, and Markus Frank, MD, using work done at Massachusetts Eye and Ear/Schepens Eye Research Institute, Boston Children's Hospital, Brigham and Women's Hospital, and the US Department of Veterans Affairs Boston Healthcare System.

In some people blood vessels grow onto the cornea, vision clouding known as corneal blindness results. This condition is caused when limbus stem cells, located behind the cornea, are destroyed by injury, infection or autoimmune disease. Outcomes are inconsistent, but limbal stem cell transplants from an uninjured eye or deceased organ donor have had promising results.

"Previously published work on limbal epithelial cell grafts showed that when more than three percent of transplanted cells were stem cells, transplants were successful - less than three percent and the transplants were not," said HSCI Affiliated Faculty member Natasha Frank.

"The question in the field then was whether we could enrich the limbal stem cells. But until this study there was no specific marker that could isolate these cells," added Frank.
Info

How evolving traits helped humans survive unstable world

Fossil Skulls
© Chip Clark, Smithsonian Human Origins Program (left three); Guram Bumbiashvili, Ge orgian National Museum (right)
Three early human species likely co-existed at the dawn of humanity between 2.1 million and 1.8 million years ago, including the 1470 group (likely Homo rudolfensis) and the 1813 group, likely Homo habilis, (left and second from left, respectively). The other fossils represent Homo erectus, which evolved by 1.8 million to 1.9 million years ago.
Three different human species may have walked the Earth at the dawn of the human lineage, dividing up their environment in slightly different ways, and the ancestors of modern humans may have survived because oftraits such as large brains that helped them adapt to unstable, shifting landscapes, researchers say.

Moreover, the defining features of the human lineage may not have evolved together gradually at once, but piecemeal in stages over millions of years, scientists added.

Modern humans, Homo sapiens, are the only living members of the human lineage, the genus Homo, which is thought to have arisen in Africa more than 2 million years ago. Many now-extinct human species were thought to once roam the planet, such as Homo erectus, the first to regularly keep the tools it made.

Many traits unique to the human lineage were long thought to have originated between 2.4 million and 1.8 million years ago in Africa. These include a large brain and body, long legs, reduced differences between the sexes, increased meat-eating, prolonged maturation periods, increased social cooperation and tool making.

However, recent fossil evidence suggests these traits did not arise together as a single package. Instead, key human features evolved piecemeal at separate times, with some emerging substantially earlier and some later than previously thought.

For instance, recent findings suggest long legs, a feature once considered unique to humans, developed in earlier ancestors, the genus Australopithecus, between 3 million and 4 million years ago, and stone tools about 2.6 million years old may predate the origin of Homo.
Telescope

Standard model for planetary system formation in trouble?

proto-planetary disk
© NASA
Artist's concept of a protoplanetary disk
Not so long ago - as recently as the mid-1990s, in fact - there was a theory so beautiful that astronomers thought it simply had to be true.

They gave it a rather pedestrian name: the core-accretion theory. But its beauty lay in how it used just a few basic principles of physics and chemistry to account for every major feature of our Solar System. It explained why all the planets orbit the Sun in the same direction; why their orbits are almost perfectly circular and lie in or near the plane of the star's equator; why the four inner planets (Mercury, Venus, Earth and Mars) are comparatively small, dense bodies made mostly of rock and iron; and why the four outer planets (Jupiter, Saturn, Uranus and Neptune) are enormous, gaseous globes made mostly of hydrogen and helium. And because the same principles of physics and astronomy must apply throughout the Universe, it predicted that any system of 'exoplanets' around another star would look pretty much the same.

But in the mid-1990s, astronomers actually started finding those exoplanets - and they looked nothing like those in our Solar System. Gas giants the size of Jupiter whipped around their stars in tiny orbits, where core accretion said gas giants were impossible. Other exoplanets traced out wildly elliptical orbits. Some looped around their stars' poles. Planetary systems, it seemed, could take any shape that did not violate the laws of physics.
Bullseye

Hackers attack US and European energy firms with Stuxnet-like viruses

computer output
© Reuters / Kacper Pempel
Hackers are targeting energy companies in the US and Europe in an apparent case of industrial espionage, according to several security companies, which say the perpetrators seem to be based in Eastern Europe.

The group of hackers, known as 'Energetic Bear' or 'Dragonfly', are attacking hundreds of Western oil and gas companies, as well as energy investment firms, and infecting them with malware capable of disrupting power supplies.

Additional targets have included energy grid operators, major electricity generation firms, petroleum pipeline operators, and industrial energy equipment providers. The majority of the victims were located in the United States, Spain, France, Italy, Germany, Turkey, and Poland, according to a Symantec report released on Monday.
Meteor

Mysterious 'bullet' asteroid may shed light on explosion of life on Earth

© Image from wikipedia.org
Researchers have discovered a fossilized space rock that stands out against anything seen before. It may advance the understanding of the asteroid clash that triggered off the diversity boom of life on early Earth.

Most of the meteorites that have fallen to Earth and were found during a 20-year study originate from a huge asteroid that collided with a smaller one - or even a comet - millions of years ago. But before the latest finding by Swedish scientists nothing was known about the mysterious "bullet" asteroid.

A study by a team of international researchers, prepared for print in the August edition of Earth and Planetary Science Letters journal, tells the story of the exploration of a meteorite found in Thorsberg limestone quarry, west of Stockholm, in southern Sweden.

While previous finds have become "quite boring,"according to Birger Schmitz, lead author of the study, who has led the chondrite cataloging, the most recent discovery is "a very, very strange and unusual find."
Info

Tibetans thrive at high altitudes thanks to Neanderthal cousin

Blood Sample Collection
© Beijing Genomics Institute (BGI-Shenzhen)
A researcher collects a blood sample from an ethnic Tibetan man participating in a DNA study looking into mutations that allow Tibetans to live at high altitudes.
Genetic mutations from an extinct human lineage help Tibetans and Sherpas live at high altitudes, researchers say.

The new findings add to growing evidence that interbreeding with other human lineages provided genetic variations that helped modern humans adapt as they spread across the world.

As modern humans migrated out of Africa, they had to adapt to many new environments. One noteworthy adaptation was of Tibetans adjusting to the thin air of the Tibetan plateau, which at about 2.5 miles (4 kilometers) in altitude has oxygen levels just 60 percent that of air at sea level. For instance, when at high altitudes, women who come from low altitudes usually have problems with childbirth, such as preeclampsia, which is potentially dangerous high blood pressure during pregnancy.

"Tibetans have a really good example of a human adaptation to a new environment," said study co-author Rasmus Nielsen, a population and evolutionary geneticist at the University of California, Berkeley.

Recent studies revealed how Tibetans adapted to high altitudes - a pattern of mutations in the gene EPAS1, which influences levels of hemoglobin, the protein in blood that carries oxygen around the body. Although most people experience a rise in hemoglobin levels at high altitudes, Tibetans only increase their hemoglobin levels a limited amount - too much hemoglobin in the blood can lead to a greater risk of heart disease.

To learn more about human evolution, Nielsen and his colleagues investigated how Tibetans might have developed their adaptation. Frustratingly, the research team's computer models could not at first explain how Tibetans evolved their pattern of EPAS1 mutations as quickly as they apparently did.
Butterfly

Hearing danger: Predator vibrations trigger plant chemical defenses

cabbage butterfly caterpillar
© Roger Meissen
This is a cabbage butterfly caterpillar feeding on an Arabidopsis plant where, on an adjacent leaf, a piece of reflective tape helps record vibrations.
As the cabbage butterfly caterpillar takes one crescent-shaped bite at a time from the edge of a leaf, it doesn't go unnoticed.

This tiny Arabidopsis mustard plant hears its predator loud and clear as chewing vibrations reverberate through leaves and stems, and it reacts with chemical defenses. Plants have long been known to detect sound, but why they have this ability has remained a mystery.

University of Missouri experiments mark the first time scientists have shown that a plant responds to an ecologically relevant sound in its environment.

"What is surprising and cool is that these plants only create defense responses to feeding vibrations and not to wind or other vibrations in the same frequency as the chewing caterpillar," said Heidi Appel, an investigator at MU's Bond Life Sciences Center and senior research scientist in the Division of Plant Sciences in the College of Agriculture, Food and Natural Resources.

Appel partnered with Rex Cocroft, an MU animal communication expert who studies how plant-feeding insects produce and detect vibrations traveling through their host plants.

"It is an ideal collaboration, that grew out of conversations between two people working in different fields that turned out to have an important area of overlap," said Cocroft, a professor of Biological Sciences in MU's College of Arts and Science. "At one point we began to wonder whether plants might be able to monitor the mechanical vibrations produced by their herbivores."
Black Magic

Frankensoldiers: GM blood cells to protect tomorrow's soldiers from bioweapons?

GM soldiers
© AFP Photo / Jim Watson
First Frankenfoods and now Frankensoldiers. Genetic warfare is on the horizon.
Blood transfusions containing genetically engineered cells could be the future of countering germ warfare, according to new research sponsored by DARPA, which hopes modified blood cells could help neutralize biological toxins deployed against soldiers.

In their research, scientists from the Whitehead Institute for Biomedical Research in Massachusetts were supported by the US Defence Research Projects Agency - renowned for being the scientific funding branch of the US military. The researchers involved said that the US was very interested in deploying the discovery against any biological weapons threats.

"We wanted to create high-value red cells that do more than simply carry oxygen," says Whitehead Founding Member Harvey Lodish, in a statement published on the Whitehead Institute website. Lodish collaborated with Whitehead Member Hidde Ploegh in the project.

Comment: This is without a doubt also part of the drive to create ethnic specific weapons.

See:Ethnic specific weapons: The real story behind the murder of Dr David Kelly

Fireball 4

'Unique' meteorite likely came from long-dead asteroid

Meteorite_1
© Discovery News
A well-known meteorite that was the first to be tracked by ground-based cameras as it blasted through the Earths atmosphere and quickly recovered at its Australian fall site has been identified as a geological oddity.

The Bunburra Rockhole meteorite was recovered from the Nullarbor Plain in Western Australia in 2007 and, after recent isotopic tests, its basaltic composition started a cosmic forensics investigation that has led researchers to believe it originated from an asteroid that no longer exists.

"This (meteorite) has a particular composition - which makes us think that it comes from a different body that has not been sampled before," said geochronologist and geochemist Fred Jourdan, associate professor at Curtin University, Perth. Jourdan and his team's work has been accepted for publication in the journal Geochimica et Cosmochimica Acta.
Bizarro Earth

88% of world's oceans covered by plastic garbage - report

© AFP/Mike Clarke
Entrepreneur and conservationist who lives in Hong Kong, displays rubbish on a beach on the south side of Hong Kong which has been left uncleaned.
At least 88 percent of the surface of the world's open oceans is polluted by plastic debris, says a new scientific report. The findings raise large concerns of the safety of marine life and how this ocean litter may affect food chains.

"Those little pieces of plastic, known as microplastics, can last hundreds of years and were detected in 88 percent of the ocean surface sampled during the Malaspina Expedition 2010," lead researcher and the author of the study Andres Cozar from the University of Cadiz, told AFP.

The results of the study "Plastic debris in the open ocean" are based on 3,070 total ocean samples collected around the world by Spain's Malaspina science expedition in 2010. They have been recently published in the Proceedings of the National Academy of Sciences (PNAS), an official journal of the US National Academy of Sciences (NAS).

The total amount of plastic in the open-ocean surface is estimated at between 7,000 and 35,000 tons, according to the report. This amount, though big, is lower than the scientists expected.
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