Εβδομαδιαία επιστημονική επιθεώρηση
- Earth may have kept its own water rather than getting it from asteroids_Science AAAS
- Tissue engineers recruit cells to make their own strong matrix_Brown University
- New exoplanet in our neighborhood_MIT
- New Scans Show There Might Be a Hidden Room in King Tut’s Tomb_Smithsonian
- Wailing at the wrong wall?_Popular Archaeology
- Extreme Challenge_University of Virginia
- How Humans Evolved Supersize Brains_Quanta Magazine
- Ancient mass extinction may have shrunk Earth’s creatures_Science AAAS
- NASA’s Cassini Finds Monstrous Ice Cloud in Titan’s South Polar Region_NASA
- Device can theoretically trap a light ‘bit’ for an infinite amount of time_Phys.org
- What Does it Mean to be Human?_Templeton Report
- Stream Study Raises New Questions About Lake Pollution_The University of Vermont
- Oceans of change_Science AAAS
- Around the Pier: Deep-Ocean Protections May Help Mitigate Climate Change_Scripps Institution of Oceanography
- Berkeley Lab Opens State-of-the-Art Facility for Computational Science_Berkeley Lab
Berkeley Lab Opens State-of-the-Art Facility for Computational Science
Wang Hall takes advantage of Lab’s hillside location for advanced energy efficiency
By Jon Weiner
On the eve of major climate negotiations, researchers argue that potential for long-term damage to deep oceans requires international agreement to lessen human disturbances
By Robert Monroe
In largely unseen ways, humans are changing the character of the deep oceans, disrupting environmental conditions and threatening biodiversity to an extent that could require hundreds of years or more for natural systems to recover.
Now in a new paper appearing in a special edition of the journal Science, Scripps Institution of Oceanography at UC San Diego biological oceanographer Lisa Levin and marine ecologist Nadine Le Bris of University Pierre and Marie Curie, from a joint research lab of France’s Centre National de la Recherche Scientifique, argue that international climate negotiations should include mitigation and adaptation mechanisms that support healthy oceans through protections of deep waters. _continue reading via Scripps Institution of Oceanography at UC San Diego ⇒
Oceans of change
Julia Fahrenkamp-Uppenbrink, David Malakoff, Jesse Smith, Caroline Ash, Sacha Vignieri
The phrase “climate change” typically evokes thoughts of rising air temperatures or other atmospheric phenomena such as droughts and extreme storms. Much less often do we consider the parallel changes that are occurring in the oceans, despite their extent and importance.
Climate change in the oceans has many facets. One is a rise in sea levels. Scientists are learning about how previous warm periods altered sea levels, and what that past may tell us about the future. To help us cope, so-called green infrastructure, such as planted marshes or oyster reefs, may help protect low-lying shorelines. Climate change is also creating problems for fisheries; for example, commercially valuable stocks move in response to warming seas.
Climate change has caused ocean temperatures to rise, a trend that will continue in the coming centuries even if fossil fuel emissions are curtailed. The uptake of carbon dioxide also makes the oceans more acidic, affecting the ability of organisms to create and maintain calcium-based shells and skeletons. Warm-water corals are particularly susceptible to these effects and may not survive the century unless carbon emissions are greatly reduced. Climate change impacts in the deep ocean are less visible, but the longevity and slow pace of life in the deep makes that ecosystem uniquely sensitive to environmental variability. Marine vertebrates at every depth are being affected, as are humans. Even if international negotiations like those kicking off soon in Paris succeed, we will be coping with the impacts of ocean climate change for centuries. _continue reading via Science ⇒
Stream Study Raises New Questions About Lake Pollution
New UVM research suggests that streambank erosion may soak up unwanted phosphorus—rather than cause it
For decades, phosphorus pollution has been contributing to unwanted algae blooms in many lakes—including Lake Champlain. A raft of recent research has pointed a finger at eroding streambanks, suggesting that their washed-out soils are a major source of this phosphorus flow.
But a new UVM study complicates that picture, raising questions about whether, in fact, streambank erosion is a culprit in Lake Champlain’s phosphorus problem.
The new research shows that, indeed, eroding streambanks may increase the raw-total amount of phosphorus that ends up in the lake—but, unexpectedly, some of these soils might decrease the amount of phosphorus available for algae to use in their growth. _continue reading via ⇒
As humans, how we see ourselves and relate to each other, and the world, is a crucial issue of our time. What it means to be human—and more specifically, a moral being—is the particular concern of a program at the Center for Humans and Nature, supported by a grant from the John Templeton Foundation.
The Center brings together leading scholars and bright minds across disciplines to offer accessible, diverse talks and viewpoints on this topic. In its Resilient Future Questions series, the primary question “What are the connections between culture and conscience?” was posed as part of the Foundation-supported program, giving much room for interesting discussion. How do humans discern between right and wrong? How do these decisions shape our communities and cultures? How does culture influence our values? Each question in the series is answered by invited contributors, such as scholars, writers, and scientists, and readers are able to weigh in, as well. _continue reading via Templeton Report ⇒
By Lisa Zyga
Researchers have designed a nanoscale device that, under ideal conditions, can confine a «bit» of light (that is, light with a single precise energy value) for an infinite amount of time. Although a physically realized device would inevitably lose some of the trapped light due to material imperfections, the researchers expect that it should be possible to completely compensate for this loss by incorporating some form of optical gain like that used in lasers, so that in principle the lifetime can be infinitely large even in a real device. _continue reading via phys.org ⇒
New observations made near the south pole of Titan by NASA’s Cassini spacecraft add to the evidence that winter comes in like a lion on this moon of Saturn.
Scientists have detected a monstrous new cloud of frozen compounds in the moon’s low- to mid-stratosphere – a stable atmospheric region above the troposphere, or active weather layer. _continue reading via NASA⇒
About 360 million years ago, Earth’s seas were filled with myriad fishes, including creatures the size of school buses. Then a mass extinction hit the Age of Fishes. It killed off most of the big guys, according to a new study, and effectively shrunk most vertebrate species to the size of a human forearm or smaller. The findings imply that our planet’s next mass extinction—which some believe is already underway—could similarly shrivel any species that remain.
The ancient extinction happened about 359 million years ago, at the end of the Devonian Period. A 100,000-year-long cold spell triggered the growth of glaciers almost down to tropical latitudes, says Lauren Sallan, a paleobiologist at the University of Pennsylvania. Sea level fell substantially, wiping out much of the shallow-water habitat surrounding major landmasses. Because few creatures had yet moved onto land, many ecosystems were devastated. About 96% of the world’s vertebrate species disappeared, making it one of Earth’s five largest die-offs. _continue reading via Science⇒
How Humans Evolved Supersize Brains
Scientists have begun to identify the symphony of biological triggers that powered the extraordinary expansion of the human brain.
By Ferris Jabr
Markos Kay for Quanta Magazine
There it was, sitting on the mantelpiece, staring at her with hollow eyes and a naked grin. She could not stop staring back. It looked distinctly like the fossilized skull of an extinct baboon.
That was the sort of thing Josephine Salmons was likely to know. At the time — 1924 — she was one of the only female students of anatomy attending the University of the Witwatersrand in South Africa.
On this particular day she was visiting her friend Pat Izod, whose father managed a quarry company that had been excavating limestone near the town of Taung. Workers had unearthed numerous fossils during the excavation, and the Izods had kept this one as a memento.
Salmons brought news of the skull to her professor, Raymond Dart, an anthropologist with a particular interest in the brain. He was incredulous. Very few primate fossils had been uncovered this far south in Africa. If the Taung site really housed such fossils, it would be an invaluable treasure trove.
The next morning Salmons brought Dart the skull, and he could see that she was right: The skull was undeniably simian. _continue reading via Quanta Magazine⇒
By Charles Feigenoff
You would never guess it by his even-tempered demeanor, but Haydn Wadley likes going to extremes.
“Things get pretty interesting when you take materials to their point of failure,” said Wadley, a University Professor and Edgar Starke Professor of Materials Science and Engineering at the University of Virginia. “Their sometimes spectacular failures inspire you to investigate the fundamental processes that are responsible, and that knowledge then sets the stage for designing new materials and new structures that can survive under even more extreme conditions.” _continue reading via UVA Today⇒
Challenging accepted tradition, some researchers have proposed a controversial new perspective on Jerusalem’s ancient Temple Mount and the location of the temple that was central to Israelite and Judahite worship in biblical times.
For hundreds of years, the long-accepted traditional location of the temple of Solomon and the later Second Temple expanded upon by Herod the Great in Jerusalem has placed them within the precinct that now contains the famous Haram al-Sharif (Dome of the Rock), otherwise known as the “Noble Sanctuary”. It has been a sacred space for three major world religions for centuries.
In recent years, however, some scholars have challenged the traditional view. Not without controversy, they have revolved their arguments around what they consider to be a misreading or dismissal of the literature by Josephus and others regarding the size and location of Fortress Antonia, the Roman enclave in 1st century Roman-occupied central Jerusalem that represented the might of Rome in the otherwise troublesome (for the Romans) province of Judaea.
Most recently, researcher and author Marilyn Sams has advanced the argument that Fortress Antonia, represented by tradition as a monumental or castle-like structure located during Herodian times just north of the Second Temple on the periphery of the large rectangular temple precinct, was actually a much larger complex, more akin to the typical standard Roman fortress layout that existed during the time of 1st century Jerusalem, the time of Jesus. The actual size and nature of this alternative model for Fortress Antonia, she argues, would have encompassed the area most scholars and historians have identified with the temple precinct. She bases her argument at least in part on the descriptions recorded by Josephus and others. _continue reading via Popular Archaeology⇒
More evidence shows that there could still be secrets in Tutankhamun’s resting place
For years, archaeologists have searched Egypt’s Valley of the Kings for Nefertiti’s tomb. Now, new scans of King Tutankhamun’s burial chamber support a recent theory that the boy-king’s tomb was originally meant for ancient Egypt’s most famous queen—and that her remains could lie just beyond King Tut’s.
The scans were prompted by another recent study of digital scans of the room by the archaeologist Nicholas Reeves, which suggested that a series of tiny cracks in the wall might indicate a hidden chamber. Reeves has argued for years that Tutankhamun’s tomb was originally built for Nefertiti, who was one of his father Akhenaten’s wives, but her tomb was appropriated for the young king after his sudden death at 19.
«My strong feeling is that Nefertiti may well be buried somewhere in the Valley of the Kings,» Strauss once told Peter Tyson for NOVA. «It would be wonderful to find Nefertiti’s tomb, because not only is this a person of the greatest historical importance, but it’s a period of the most superb art.» _continue reading via Smithsonian.com⇒
New exoplanet in our neighborhood
Though likely uninhabitable, planet is rocky, Earth-sized, and near enough for study of its atmosphere.
Jennifer Chu | MIT News Office
Scientists have discovered a new exoplanet that, in the language of “Star Wars,” would be the polar opposite of frigid Hoth, and even more inhospitable than the deserts of Tatooine. But instead of residing in a galaxy far, far away, this new world is, galactically speaking, practically next door.
The new planet, named GJ 1132b, is Earth-sized and rocky, orbiting a small star located a mere 39 light-years from Earth, making it the closest Earth-sized exoplanet yet discovered. Astrophysicists from MIT and elsewhere have published these findings today in the journal Nature.
Based on their measurements, the scientists have determined that the planet is a roasting 500 degrees Fahrenheit, and is likely tidally locked, meaning that it has a permanent day and night side, presenting the same face to its star, much like our moon is locked to the Earth.
Because of its scorching temperatures, GJ 1132b most likely cannot retain liquid water on its surface, making it uninhabitable for life as we know it. However, scientists say it is cool enough to host a substantial atmosphere.
The planet is also close enough to Earth that scientists may soon be able to find out much more about its characteristics, from the composition of its atmosphere to the pattern of its winds — and even the color of its sunsets. _continue reading via MIT News Office⇒
PROVIDENCE, R.I. [Brown University] — Imitation may be the sincerest form of flattery but the best way to make something is often to co-opt the original process and make it work for you. In a sense, that’s how scientists at Brown University accomplished a new advance in tissue engineering.
In the journal Biomaterials, the team reports culturing cells to make extracellular matrix (ECM) of two types and five different alignments with the strength found in natural tissue and without using any artificial chemicals that could make it incompatible to implant. _continue reading via Brown University⇒
Carl Sagan famously dubbed Earth the “pale blue dot” for our planet’s abundant water. But where this water came from—and when it arrived—has been a longstanding debate. Many scientists argue that Earth formed as a dry planet, and gained its water millions of years later through the impact of water-bearing asteroids or comets. But now, scientists say that Earth may have had water from the start, inheriting it directly from the swirling nebula that gave birth to the solar system. If true, the results suggest that water-rich planets may abound in the universe.
“This is a great test of our canonical picture for how Earth got its water, and it suggests that things are not as simple as we first thought,” says Fred Ciesla of the University of Chicago in Illinois, who was not involved in the new study. To understand the origin of Earth’s water, scientists have fingerprinted potential sources, like asteroids and comets, using the ratio of light to heavy hydrogen isotopes. Then, researchers can compare the ratios with those found in water sources on Earth.
However, researchers don’t really know the true hydrogen isotopic composition of Earth’s water, says Lydia Hallis, a planetary scientist at the University of Glasgow in the United Kingdom and lead author of the new study. Scientists have often assumed that the isotopic signature of seawater is close to the true value, but Hallis thinks this has probably changed over geologic time, as Earth preferentially lost light hydrogen atoms to space and gained water from asteroid and comet impacts. _continue reading via Science⇒