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Earthquakes make gold veins -- pressure changes in Earth crust cause precious metals to deposit

Earthquakes make gold veins -- pressure changes in Earth crust cause precious metals to deposit | Amazing Science | Scoop.it

Scientists have long known that veins of gold are formed by mineral deposition from hot fluids flowing through cracks deep in Earth’s crust. But a study published today in Nature Geoscience has found that the process can occur almost instantaneously — possibly within a few tenths of a second.

 

The process takes place along 'fault jogs' — sideways zigzag cracks that connect the main fault lines in rock, says first author Dion Weatherley, a seismologist at the University of Queensland in Brisbane, Australia.

When an earthquake hits, the sides of the main fault lines slip along the direction of the fault, rubbing against each other. But the fault jogs simply open up. Weatherley and his co-author, geochemist Richard Henley at the Australian National University in Canberra, wondered what happens to fluids circulating through these fault jogs at the time of the earthquake.

 

What their calculations revealed was stunning: a rapid depressurization that sees the normal high-pressure conditions deep within Earth drop to pressures close to those we experience at the surface. For example, a magnitude-4 earthquake at a depth of 11 kilometres would cause the pressure in a suddenly opening fault jog to drop from 290 megapascals (MPa) to 0.2 MPa. (By comparison, air pressure at sea level is 0.1 MPa.) “So you’re looking at a 1,000-fold reduction in pressure,” Weatherley says.

 

Big earthquakes will produce bigger pressure drops, but for gold-vein formation, that seems to be overkill. More interesting, Weatherley and Henley found, is that even small earthquakes produce surprisingly big pressure drops along fault jogs. “We went all the way to magnitude –2,” Weatherley says — an earthquake so small, he adds, that it involves a slip of only about 130 micrometres along a mere 90 centimetres of the fault zone. “You still get a pressure drop of 50%,” he notes.


That, Weatherley adds, might be one of the reasons that the rocks in gold-bearing quartz deposits are often marbled with a spider web of tiny gold veins. “You [can] have thousands to hundreds of thousands of small earthquakes per year in a single fault system,” he says. “Over the course of hundreds of thousands of years, you have the potential to precipitate very large quantities of gold. Small bits add up.”

 

Weatherley says that prospectors might be able to use remote sensing techniques to find new gold deposits in deeply buried rocks in which fault jogs are common. “Fault systems with lots of jogs can be places where gold can be distributed,” he explains.

 

But Taka’aki Taira, a seismologist at the University of California, Berkeley, thinks that the finding might have even more scientific value. That’s because, in addition to showing how quartz deposits might form in fault jogs, the study reveals how fluid pressure in the jogs rebounds to its original level — something that could affect how much the ground moves after the initial earthquake.

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20,000+ FREE Online Science and Technology Lectures from Top Universities | Amazing Science | Scoop.it

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Short transient rapamycin treatment increases lifespan in mice by over 50%

Short transient rapamycin treatment increases lifespan in mice by over 50% | Amazing Science | Scoop.it

Old age is the single greatest risk factor for many diseases including heart disease, arthritis, cancer and dementia. By delaying the biological aging process, it may be possible to reduce the impact of age-related diseases, which could have great benefits for society and the quality of life of individuals. A drug called rapamycin, which is currently used to prevent organ rejection in transplant recipients, is a leading candidate for targeting aging. Rapamycin increases lifespan in several types of animals and delays the onset of many age-related conditions in mice.

 

Nearly all of the aging-related studies in mice have used the same dose of rapamycin given throughout the lives of the animals. Lifelong treatment with rapamycin wouldn’t be practical in humans and is likely to result in undesirable side effects. For example, the high doses of rapamycin used in transplant patients cause side effects including poor wound healing, elevated blood cholesterol levels, and mouth ulcers. Before rapamycin can be used to promote healthy aging in humans, researchers must better understand at what point in life the drug is most effective, and what dose to use to provide the biggest benefit while limiting the side effects.

 

Now, Bitto et al. show that treating mice with rapamycin for a short period during middle age increases the life expectancy of the mice by up to 60%. In the experiments, mice were given two different doses of rapamycin for only three months starting at 20 months old (equivalent to about 60-65 years old in humans). After receiving the lower dose, both male and female mice lived about 50% longer than untreated mice, and showed improvements in their muscle strength and motor coordination. When given the higher dose, male mice showed an even greater increase in life expectancy, but the female mice did not. These female mice had an increased risk of developing rare and aggressive forms of blood cancer, but were protected from other types of cancer.

 

Both drug treatments also caused substantial changes in the gut bacteria of the male and female mice, which could be related to effects of rapamycin on metabolism, immunity and health. More studies are needed to uncover precisely how such short-term treatments can yield long-term changes in the body, and how such changes are related to lifespan and healthy aging.

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Cancer surpasses heart disease as the leading cause of death in California

Cancer surpasses heart disease as the leading cause of death in California | Amazing Science | Scoop.it

ncer has surpassed heart disease as the leading cause of death in California and 21 other states, according to a new report from the Centers for Disease Control and Prevention. That total is in stark contrast to the situation at the start of this century, when only two states — Alaska and Minnesota — lost more people to cancer than heart disease. And it’s a huge departure from the situation in the 1950s, when the number of heart disease deaths was 2½ times bigger than the number of cancer fatalities.

 
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One-atom-thick graphene balloons can withstand enormous pressures

One-atom-thick graphene balloons can withstand enormous pressures | Amazing Science | Scoop.it

Small balloons made from one-atom-thick material graphene can withstand enormous pressures, much higher than those at the bottom of the deepest ocean, scientists at the University of Manchester report.

 

This is due to graphene's incredible strength - 200 times stronger than steel. The graphene balloons routinely form when placing graphene on flat substrates and are usually considered a nuisance and therefore ignored. The Manchester researchers, led by Professor Irina Grigorieva, took a closer look at the nano-bubbles and revealed their fascinating properties.

 

These bubbles could be created intentionally to make tiny pressure machines capable of withstanding enormous pressures. This could be a significant step towards rapidly detecting how molecules react under extreme pressure.

 

Writing in Nature Communications, the scientists found that the shape and dimensions of the nano-bubbles provide straightforward information about both graphene's elastic strength and its interaction with the underlying substrate.

 

The researchers found such balloons can also be created with other two-dimensional crystals such as single layers of molybdenum disulfide (MoS2) or boron nitride.

 

They were able to directly measure the pressure exerted by graphene on a material trapped inside the balloons, or vice versa.

 

To do this, the team indented bubbles made by graphene, monolayer MoS2 and monolayer boron nitride using a tip of an atomic force microscope and measured the force that was necessary to make a dent of a certain size.

 

These measurements revealed that graphene enclosing bubbles of a micron size creates pressures as high as 200 megapascals, or 2,000 atmospheres. Even higher pressures are expected for smaller bubbles.

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Fossilized rivers suggest warm, wet ancient Mars

Fossilized rivers suggest warm, wet ancient Mars | Amazing Science | Scoop.it

Extensive systems of fossilized riverbeds have been discovered on an ancient region of the Martian surface, supporting the idea that the now cold and dry Red Planet had a warm and wet climate about 4 billion years ago, according to UCL-led research.

 

The study, published in Geology and funded by the Science & Technology Facilities Council and the UK Space Agency, identified over 17,000km of former river channels on a northern plain called Arabia Terra, providing further evidence of water once flowing on Mars.

"Climate models of early Mars predict rain in Arabia Terra and until now there was little geological evidence on the surface to support this theory. This led some to believe that Mars was never warm and wet but was a largely frozen planet, covered in ice-sheets and glaciers. We've now found evidence of extensive river systems in the area which supports the idea that Mars was warm and wet, providing a more favourable environment for life than a cold, dry planet," explained lead author, Joel Davis (UCL Earth Sciences).

Since the 1970s, scientists have identified valleys and channels on Mars which they think were carved out and eroded by rain and surface runoff, just like on Earth. Similar structures had not been seen on Arabia Terra until the team analysed high resolution imagery from NASA's Mars Reconnaissance Orbiter (MRO) spacecraft.

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A Sonic Hot Plasma Boom Half as Old as the Universe Itself

A Sonic Hot Plasma Boom Half as Old as the Universe Itself | Amazing Science | Scoop.it
That’s quite a sonic boom, particularly given that the speed of sound in the hot plasma is around 2 million miles per hour!

 

In a normal cluster, the three components (galaxies, ICM, and dark matter) all lie on top of one another. But when two clusters collide, the components can separate. Dark matter only feels the pull of gravity, but the ICM also experiences friction and gas pressure. The dark matter components whiz past one another while the ICM sticks together, as in the famous example of the Bullet Cluster, shown above. It’s like if two water balloons collide: the rubber (ICM) stays put in the middle, while the water (dark matter) is free to keep flying past.

 

The authors of a recent paper are catching this process in action. Specifically, they measure theshockwave in the ICM gas from the collision of two galaxy clusters, in “El Gordo”. The ICM, like any gas, has a natural sound speed (which depends on its temperature). When gas moves faster than its sound speed, it creates shockwaves, where the pressure builds significantly and the gas is superheated. This same process is what creates a sonic boom on Earth.

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New flexible material can make any window 'smart'

New flexible material can make any window 'smart' | Amazing Science | Scoop.it

Researchers in the Cockrell School of Engineering at The University of Texas at Austin have invented a new flexible smart window material that, when incorporated into windows, sunroofs, or even curved glass surfaces, will make these structures "smart".

 

Delia Milliron, an associate professor in the McKetta Department of Chemical Engineering, and her team's advancement is a new low-temperature process for coating the new smart material on plastic, which makes it easier and cheaper to apply than conventional coatings made directly on the glass itself. The team demonstrated a flexible electrochromic device, which means a small electric charge (about 4 V) can lighten or darken the material and control the transmission of heat-producing, near-infrared radiation. Such smart windows are aimed at saving on cooling and heating bills for homes and businesses.

 

The research team is an international collaboration, including scientists at the European Synchrotron Radiation Facility and CNRS in France, and Ikerbasque in Spain. Researchers at UT Austin's College of Natural Sciences provided key theoretical work.

 

Milliron and her team's low-temperature process generates a material with a unique nanostructure, which doubles the efficiency of the coloration process compared with a coating produced by a conventional high-temperature process. It can switch between clear and tinted more quickly, using less power.

The new electrochromic material, like its high-temperature processed counterpart, has an amorphous structure, meaning the atoms lack any long-range organization as would be found in a crystal. However, the new process yields a unique local arrangement of the atoms in a linear, chain-like structure.

 

Whereas conventional amorphous materials produced at high temperature have a denser three-dimensionally bonded structure, the researchers' new linearly structured material, made of chemically condensed niobium oxide, allows ions to flow in and out more freely. As a result, it is twice as energy efficient as the conventionally processed smart window material.

At the heart of the team's study is their rare insight into the atomic-scale structure of the amorphous materials, whose disordered structures are difficult to characterize.

 

Because there are few techniques for characterizing the atomic-scale structure sufficiently enough to understand properties, it has been difficult to engineer amorphous materials to enhance their performance.

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Carp undergo ‘reverse evolution’ to get scales back

Carp undergo ‘reverse evolution’ to get scales back | Amazing Science | Scoop.it

Evolution is a slow process, often taking thousands or even millions of years. But it can be quick when it needs to be. Take the case of the common carp (Cyprinus carpio). The species, like most fish, is covered in scales, but medieval European monks selectively bred carp centuries ago to produce ones with fewer scales, thus making them easier to gut and cook. Starting in 1912, these “mirror carp”—so named for their smooth sides—were introduced to Madagascar, where no carp existed, for fish farming, and they quickly spread throughout the island.

 

However, by the late 1950s, people observed the mirror carp’s descendants “degenerating” into more scaled fish. In a study, published today in the Proceedings of the Royal Society B, researchers collected nearly 700 wild and farmed carp from across Madagascar and studied their scale patterns and genotypes. Roughly 65% of the wild carp, which mostly descended from the original mirror carp released into the wild, were fully scaled, despite all still carrying the genetic mutation that originally turned their ancestors into mirror carp.

 

The newly scaled carp had evolved back their scales through different genes in 100 years, or roughly 40 carp generations, the team concludes. Scaled carp have been shown to survive better in the wild than mirror carp, likely because of the protection that scales offer from predators and parasites, and their reappearance shows just how much pressure a creature’s environment can put on an animal to quickly evolve.

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„Artificial Atom“ Created in Graphene

„Artificial Atom“ Created in Graphene | Amazing Science | Scoop.it

In a tiny quantum prison, electrons behave quite differently as compared to their counterparts in free space. They can only occupy discrete energy levels, much like the electrons in an atom -- for this reason, such electron prisons are often called "artificial atoms." Artificial atoms may also feature properties beyond those of conventional ones, with the potential for many applications for example in quantum computing. Such additional properties have now been shown for artificial atoms in the carbon material graphene. The results have been published in the journal Nano Letters, the project was a collaboration of scientists from TU Wien (Vienna, Austria), RWTH Aachen (Germany) and the University of Manchester (GB).

 

"Artificial atoms open up new, exciting possibilities, because we can directly tune their properties," says Professor Joachim Burgdörfer (TU Wien, Vienna). In semiconductor materials such as gallium arsenide, trapping electrons in tiny confinements has already been shown to be possible. These structures are often referred to as "quantum dots." Just like in an atom, where the electrons can only circle the nucleus on certain orbits, electrons in these quantum dots are forced into discrete quantum states.

Even more interesting possibilities are opened up by using graphene, a material consisting of a single layer of carbon atoms, which has attracted a lot of attention in the last few years.

 

"In most materials, electrons may occupy two different quantum states at a given energy. The high symmetry of the graphene lattice allows for four different quantum states. This opens up new pathways for quantum information processing and storage" explains Florian Libisch from TU Wien. However, creating well-controlled artificial atoms in graphene turned out to be extremely challenging.

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Could Hydrogen Soon Be Classed as a Precious Metal?

Could Hydrogen Soon Be Classed as a Precious Metal? | Amazing Science | Scoop.it

Hydrogen is the first chemical element listed in the periodic table and has the atomic number of 1.  Up until now, hydrogen has usually been classed as a gas or liquid, but scientists are now extremely close to producing the first ever sample of solid metallic hydrogen. Their progress so far has been achieved through the use of powerful lasers, electrical impulses, and other state-of-the-art equipment.

 

As research continues, scientists uncover more about the properties of hydrogen and how it can benefit us as humans. It is a simple element that has the ability to change phases based on temperature and pressure and could be the next big superconductor.  Others that are currently used on MRIs and the Large Hadron Collider only work when they are cooled to extremely low temperatures. But with metallic hydrogen, it has the potential to act as a superconductor just at room temperature.

 

Various techniques and experiments are being conducted at the moment to try and be the first to produce metallic hydrogen successfully.  One of the ways that are being trialed involves a diamond anvil.  Here two tapered diamonds are used to exert intense pressure onto the sample of hydrogen, but this achieves the fourth phase of solid hydrogen, not metallic hydrogen, so more work is still needed here.  Others have begun to use lasers to blast samples of hydrogen, therefore increasing the pressure and temperature temporarily.

 

Although all of these experiments showed some evidence of metallic behavior, it was only liquid metal.  Other techniques involve using intense bursts of electrical power, as the Z Machine at Sandia National Laboratories, to force a metal plate into the hydrogen samples.  Scientists are confident that metallic hydrogen exists in the solar system, it is now just a case of reproducing it.

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Global Initiative Seeks 1,000 New Cancer Models

Global Initiative Seeks 1,000 New Cancer Models | Amazing Science | Scoop.it

The effort will use next-generation cell-culture methods and fresh patient samples.

 

An international collaboration of cancer-research heavy-weights aims to grow 1,000 new cell lines for scientists to study — and that could be just the beginning. The Human Cancer Models Initiative announced its pilot project on July 11, and intends to complete the initial 1,000 models within 3 years. Members of the initiative include the US National Cancer Institute (NCI) in Bethesda, Maryland; Cancer Research UK in London; the Wellcome Trust Sanger Institute in Hinxton, UK; and Hubrecht Organoid Technology of Utrecht in the Netherlands.

 

The initial goal of 1,000 cell lines would roughly double the world’s collection of accessible cancer cell models, says Louis Staudt, head of the NCI’s Center for Cancer Genomics. But if all goes well during the pilot, the project will generate thousands more. Staudt estimates that researchers need about 10,000 models to fully capture the diversity of relatively common genetic subtypes of cancer. “Whether we actually will push into that depends a lot upon how easy and valuable the cell lines are from the pilot,” he says.

 

The initiative’s models will offer several improvements over most available cell lines. Each line will be matched with clinical data about the donor patient, and how they responded to treatment. The project will also use cutting-edge techniques to generate its models, which will include 3D cultures called organoids, and cells that have been reprogrammed to grow indefinitely in culture.

 

The hope is that these features will better reflect human cancers, enabling the cells to be used to model disease, screen for new drugs and determine which treatments are suited for which cancers.

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Hybrid system designed to harvest 'full spectrum' of solar energy

Hybrid system designed to harvest 'full spectrum' of solar energy | Amazing Science | Scoop.it
A new concept could bring highly efficient solar power by combining three types of technologies that convert different parts of the light spectrum and also store energy for use after sundown.

Combining the technologies could make it possible to harness and store far more of the spectrum of sunlight than is possible using any one of the technologies separately.

"Harvesting the full spectrum of sunlight using a hybrid approach offers the potential for higher efficiencies, lower power production costs, and increased power grid compatibility than any single technology by itself," said Peter Bermel, an assistant professor in Purdue University's School of Electrical and Computer Engineering. "The idea is to use technologies that, for the most part exist now, but to combine them in a creative way that allows us to get higher efficiencies than we normally would."

The approach combines solar photovoltaic cells, which convert visible and ultraviolet light into electricity, thermoelectric devices that convert heat into electricity, and steam turbines to generate electricity. The thermoelectric devices and steam turbines would be driven by heat collected and stored using mirrors to focus sunlight onto a newly designed "selective solar absorber and reflector."

"This is a spectrally selective system, so it is able to efficiently make use of as much of the spectrum as possible," he said. "The thermal storage allows for significant flexibility in the time of power generation, so the system can produce power for hours after sunset, providing a consistent source of power throughout the day."

Findings from the research are detailed in a paper with an advance online publication date of Aug. 15, and the paper is scheduled to appear in a future print issue of the journal Energy & Environmental Science.

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New kind of substances inhibits viruses and bacteria

New kind of substances inhibits viruses and bacteria | Amazing Science | Scoop.it

A new class of substances is effective against both the AIDS pathogen, HIV, and antibiotics-resistant MRSA bacteria. These two pathogensoften occur together. Scientists hope that it may be possible to control them with a single drug in the future. Scientists of the Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) developed so-called dual agents that inhibit the growth of both types of pathogens. They describe their findings in the renowned Journal of Medicinal Chemistry. The HIPS is the Saarbrücken branch of the Helmholtz Centre for Infection Research (HZI), which has its headquarters in Braunschweig. It was founded jointly by the HZI and Saarland University in 2009.

 

The human immunodeficiency virus HIV is one of the most dangerous and widespreadpathogens throughout the world. Some 37 million people are host to the virus and 1.2 million were killed by this disease in 2014 alone. Meanwhile, both the proliferation of the pathogen and the progression of the disease can be halted through a combination therapy, but the viruses show an increasing trend to develop resistance and no longer respond to the medications used against them.

 

The notorious MRSA bacteria, i.e. methicillin-resistant Staphylococcus aureus strains, show similar persistence as many common antibiotics have become ineffective. HIV patients, whose immune systemhas already been weakened by the disease, are often additionally afflicted by MRSA pathogens. These co-infections are very problematic and difficult to treat. "Resistance to the common therapies is quite widespread amongst both the viruses and the MRSA bacteria, which means that the co-infection is very difficult to control," explains HZI scientist Prof Rolf Hartmann, who is the head of the "Drug Design and Optimization" department at the HIPS. "In addition, it is necessary to carefully consider the interactions between the medications given to the patients."

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Goldilocks zone alone not sufficient for search of habitable planets

Goldilocks zone alone not sufficient for search of habitable planets | Amazing Science | Scoop.it

For decades, it has been thought that the key factor in determining whether a planet can support life was its distance from its sun. In our solar system, for instance, Venus is too close to the sun and Mars is too far, but Earth is just right. That distance is what scientists refer to as the "habitable zone," or the "Goldilocks zone."

It also was thought that planets were able to self-regulate their internal temperature via mantle convection—the underground shifting of rocks caused by internal heating and cooling. A planet might start out too cold or too hot, but it would eventually settle into the right temperature.

A new study, appearing in the journal Science Advances, suggests that simply being in the habitable zone isn't sufficient to support life. A planet also must start with an internal temperature that is just right.

"If you assemble all kinds of scientific data on how Earth has evolved in the past few billion years and try to make sense out of them, you eventually realize that mantle convection is rather indifferent to the internal temperature," said Jun Korenaga, author of the study and professor of geology and geophysics at Yale. Korenaga presents a general theoretical framework that explains the degree of self-regulation expected for mantle convection and suggests that self-regulation is unlikely for Earth-like planets.

"The lack of the self-regulating mechanism has enormous implications for planetary habitability," Korenaga said. "Studies on planetary formation suggest that planets like Earth form by multiple giant impacts, and the outcome of this highly random process is known to be very diverse."

Such diversity of size and internal temperature would not hamper planetary evolution if there was self-regulating mantle convection, Korenaga said. "What we take for granted on this planet, such as oceans and continents, would not exist if the internal temperature of Earth had not been in a certain range, and this means that the beginning of Earth's history cannot be too hot or too cold."

The NASA Astrobiology Institute supported the research. Korenaga is a co-investigator of the NASA "Alternative Earths" team, which is organized around the principle of understanding how the Earth has maintained a persistent biosphere through most of its history, how the biosphere manifests in "biosignatures" on a planetary scale, and how reconstructing this history can inform the search for life within and beyond the solar system.

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Researchers Discover How Zika Virus Causes Fetal Brain Damage

Researchers Discover How Zika Virus Causes Fetal Brain Damage | Amazing Science | Scoop.it
According to a team of researchers led by Yale University, infection by the Zika virus diverts a key protein necessary for neural cell division in the developing human fetus.

 

Marco Onorati et al. describe the derivation and characterization, including single-cell RNA-seq, of neocortical and spinal cord neuroepithelial stem (NES) cells to model early human neurodevelopment and Zika virus (ZIKV)-related neuropathogenesis. By analyzing human NES cells, organotypic fetal brain slices, and a ZIKV-infected micrencephalic brain, the team shows that ZIKV infects both neocortical and spinal NES cells as well as their fetal homolog, radial glial cells (RGCs), causing disrupted mitoses, supernumerary centrosomes, structural disorganization, and cell death. ZIKV infection of NES cells and RGCs causes centrosomal depletion and mitochondrial sequestration of phospho-TBK1 during mitosis.

 

The scientists also found that nucleoside analogs inhibit ZIKV replication in NES cells, protecting them from ZIKV-induced pTBK1 relocalization and cell death. They established a model system of human neural stem cells to reveal cellular and molecular mechanisms underlying neurodevelopmental defects associated with ZIKV infection and its potential treatment.

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Harvard researchers pinpoint enzyme (RIPK1) that triggers cell demise in ALS

Harvard researchers pinpoint enzyme (RIPK1) that triggers cell demise in ALS | Amazing Science | Scoop.it

Scientists from Harvard Medical School (HMS) have identified a key instigator of nerve cell damage in people with amyotrophic lateral sclerosis, or ALS, a progressive and incurable neurodegenerative disorder.

 

Researchers say the findings of their study, published Aug. 5 in the journal Science, may lead to new therapies to halt the progression of the uniformly fatal disease that affects more than 30,000 Americans. One such treatment is already under development for testing in humans after the current study showed it stopped nerve cell damage in mice with ALS.

 

The onset of ALS, also known as Lou Gehrig’s disease, is marked by the gradual degradation and eventual death of neuronal axons, the slender projections on nerve cells that transmit signals from one cell to the next. The HMS study reveals that the aberrant behavior of an enzyme called RIPK1 (receptor interacting serine/threonine kinase 1) damages neuronal axons by disrupting the production of myelin, the soft, gel-like substance that envelopes axons to insulate them from injury.

 

“Our study not only elucidates the mechanism of axonal injury and death but also identifies a possible protective strategy to counter it by inhibiting the activity of RIPK1,” said the study’s senior investigator, Junying Yuan, the Elizabeth D. Hay Professor of Cell Biology at HMS.

 

The new findings come on the heels of a series of pivotal discoveries Yuan and colleagues made over the last decade, which revealed RIPK1 as a key regulator of inflammation and cell death. But until now, scientists were unaware of its role in axonal demise and ALS. Experiments conducted in mice and in human ALS cells reveal that when RIPK1 is out of control, it can spark axonal damage by setting off a chemical chain reaction that culminates in stripping the protective myelin off axons and triggering axonal degeneration — the hallmark of ALS.

 

RIPK1, the researchers found, inflicts damage by directly attacking the body’s myelin production plants — nerve cells known as oligodendrocytes, which secrete the soft substance, rich in fat and protein, that wraps around axons to support their function and shield them from damage. Building on previous work from Yuan’s lab showing that RIPK1’s activity could be blocked by a chemical called necrostatin-1, the research team tested how ALS cells in lab dishes would respond to the same treatment. Indeed, necrostatin-1 tamed the activity of RIPK1 in cells of mice genetically altered to develop ALS.

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Organic Farms Yield 20% Fewer Crops than Conventional Farms and No Healthier Food

Organic Farms Yield 20% Fewer Crops than Conventional Farms and No Healthier Food | Amazing Science | Scoop.it

People buy organic food for many different reasons, most of which are factually incorrect. Quite possibly the biggest myth about organic food is that it is grown without pesticides. That is simply untrue. Others have been led to believe that organic food is healthier and tastier* than conventionally grown food. Those myths have also been busted. Another justification for organic food is that it is more sustainable and environmentally friendly. Those myths, too, already have been exposed, but a new paper inPLoS ONE puts another nail into the coffin.

 

The authors obtained data from crop yield surveys conducted by the USDA in 2014. To control for the influence of geography, they paired the data so that crop yields could only be compared for farmers who lived in the same state. (For example, organic grape growers in Washington State could only be compared with conventional grape growers who also farmed in Washington.) What did they find?

 

As suspected, organic farms are not as productive as conventional ones. In fact, the overall average is that organic farming produces 20% fewer crops.

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Gravitational waves will bring the extreme universe into view – Daniel Hoak | Aeon Ideas

The first direct detection of gravitational waves on 14 September 2015 proved that massive objects can ripple the structure of space, verifying a key prediction of Albert Einstein’s general theory of relativity. The second detection, made on 26 December 2015 and announced this June, firmly established gravitational waves as a new window to the Universe. But even more exciting are the detections yet to come: the thousands of signals that should soon be observed by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo experiments. They will transform our understanding of black holes, neutron stars, supernova explosions, and perhaps even the origin and fate of the cosmos itself.

 

Changes to the fields of physics and astronomy are already being felt. The two events reported so far have significantly increased the number of known stellar-mass black holes, and have demonstrated that black holes can form tight pairs and merge violently within the lifetime of the Universe; such mergers are the inferred cause of the September 14 and December 26 signals. Drawing on data from those two events, my colleagues in the LIGO and Virgo collaborations have tested general relativity in novel ways, far outside our terrestrial experience. And we have shown that black holes collide more often than expected, which has lead some researchers to speculate that black holes might be abundant enough to qualify as a variety of dark matter.

 

As with any new observational tool, the most important discoveries from the new detectors will surely be the ones that are unexpected. But we also have a good sense of the amazing things that the gravitational universe will tell us, even in the absence of surprises.

 

We can be certain that we will detect many more merging pairs of black holes comparable to the two already detected. The current instruments are about three times less sensitive than their full potential. At their ultimate sensitivity, the two LIGO detectors (in Louisiana and Washington state) and the Virgo experiment (near Pisa in Italy) will register dozens to hundreds of black-hole events per year. This large sample will yield a detailed census of black holes, and will allow astronomers to characterize their population all across the Universe, evaluating theories of how they form.

 

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Scientists say they’ve found a planet orbiting Proxima Centauri, our closest neighbor

Scientists say they’ve found a planet orbiting Proxima Centauri, our closest neighbor | Amazing Science | Scoop.it

Scientists have discovered what they believe to be a new planet, the closest one ever detected outside our solar system. It is a small, rocky planet not unlike our own, orbiting the sun's closest stellar neighbor.

 

Astronomers have long suspected that the star Proxima Centauri could be home to a planet, but proof had been elusive. Dim red dwarf stars like Proxima have been found to host billions of small, closely orbiting planets throughout the galaxy. Now a study published Wednesday in the journal Natureprovides the best evidence yet for a tantalizingly close target on which to seek alien life.

 

"It's so inspiring, it's our closest star," Lisa Kaltenegger, a Cornell astronomer who wasn't involved in the new study, told The Washington Post. "A planet next door. How much more inspiring can it get?"

 

Located about 4.25 light-years from the sun, Proxima is less famous than the Alpha Centauri binary star system it hangs around with. But while Alpha Centauri is made up of two rather sun-like stars, Proxima is actually closer. It used to be that scientists were far more interested in stars like our own sun than in dim little dwarves like Proxima, but the times are changing — these types of stars are far more common in the galaxy, and scientists now believe they might be just as capable of hosting life as more familiar looking suns.

 

The proposed planet comes to light not long after a would-be-world orbiting Alpha Centauri B was determined to be nothing but a fluke in the data. Scientists know that most stars in the galaxy harbor planets, but we've had difficulty finding our closest companions in the cosmos.

 

Proxima b will no doubt be dubbed "Earthlike" by many, but let's not jump the gun. Here's what we know: The planet, based on statistical analysis of the behavior of its star, is quite likely to exist. Beyond that, we know very little.

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Light and matter merge in quantum coupling

Light and matter merge in quantum coupling | Amazing Science | Scoop.it
Where light and matter intersect, the world illuminates. Where light and matter interact so strongly that they become one, they illuminate a world of new physics, according to Rice University scientists.

 

Rice physicists are closing in on a way to create a new condensed matter state in which all the electrons in a material act as one by manipulating them with light and a magnetic field. The effect made possible by a custom-built, finely tuned cavity for terahertz radiation shows one of the strongest light-matter coupling phenomena ever observed.

 

The work by Rice physicist Junichiro Kono and his colleagues is described in Nature Physics. It could help advance technologies like quantum computers and communications by revealing new phenomena to those who study cavity quantum electrodynamics and condensed matter physics, Kono said.

 

Condensed matter in the general sense is anything solid or liquid, but condensed matter physicists study forms that are much more esoteric, like Bose-Einstein condensates. A Rice team was one of the first to make a Bose-Einstein condensate in 1995 when it prompted atoms to form a gas at ultracold temperatures in which all the atoms lose their individual identities and behave as a single unit.

 

The Kono team is working toward something similar, but with electrons that are strongly coupled, or "dressed," with light. Qi Zhang, a former graduate student in Kono's group and lead author of the paper, designed and constructed an extremely high-quality cavity to contain an ultrathin layer of gallium arsenide, a material they've used to study superfluorescence. By tuning the material with a magnetic field to resonate with a certain state of light in the cavity, they prompted the formation of polaritons that act in a collective manner.

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New theory of how we move through time

New theory of how we move through time | Amazing Science | Scoop.it

Associate Professor Dr Joan Vaccaro, of Griffith's Centre for Quantum Dynamics, has solved an anomaly of conventional physics and shown that a mysterious effect called 'T violation' could be the origin of time evolution and conservation laws.

"I begin by breaking the rules of physics, which is rather bold I have to admit, but I wanted to understand time better and conventional physics can't do that," Dr Vaccaro says.

 

"I do get conventional physics in the end though. This means that the rules I break are not fundamental. It also means that I can see why the universe has those rules. And I can also see why the universe advances in time."

 

In her research published in The Royal Society Dr Vaccaro says T violation, or a violation of time reversal (T) symmetry, is forcing the universe and us in it, into the future. "If T violation wasn't involved we wouldn't advance in time and we'd be stuck at the Big Bang, so this shows how we escaped the Big Bang.

 

"I found the mechanism that forces us to go to the future, the reason why you get old and the reason why we advance in time." "The universe must be symmetric in time and space overall. But we know that there appears to be a preferred direction in time because we are incessantly getting older not younger."

 

The anomaly Dr Vaccaro solves involves two things not accounted for in in conventional physical theories -- the direction of time, and the behavior of the mesons, which decay differently if time went in the opposite direction.

 

Experiments show that the behavior of mesons depends on the direction of time; in particular, if the direction of time was changed then their behavior would also," she says.

 

"Conventional physical theories can accommodate only one direction of time and one kind of meson behavior, and so they are asymmetric in this regard. But the problem is that the universe cannot be asymmetric overall.

 

"This means that physical theories must be symmetric in time. To be symmetric in time they would need to accommodate both directions of time and both meson behaviors. This is the anomaly in physics that I am attempting to solve."

 

Dr Vaccaro is presenting her work at the Soapbox Science event held in Brisbane as part of National Science Week, titled "The meaning of time: why the universe didn't stay put at the big bang and how it is 'now' and no other time."

 

Without any T violation the theory gives a very strange universe. An object like a cup can be placed in time just like it is in space.

"It just exists at one place in space and one point in time. There is nothing unusual about being at one place in space, but existing at one point in time means the object would come into existence only at that point in time and then disappear immediately.

 

"This means that conservation of matter would be violated. It also means that there would be no evolution in time. People would only exist for a single point in time -- they would not experience a "flow of time."

 

When Dr Vaccaro adds T violation to the theory, things change dramatically. "The cup is now found at any and every time," she says,

 

"This means that the theory now has conservation of matter -- the conservation has emerged from the theory rather than being assumed. Moreover, objects change over time, cups chip and break, and people would grow old and experience a "flow of time." This means that the theory now has time evolution.

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Tunneling nanotubes between neurons enable the spread of Parkinson's disease via lysosomes

Tunneling nanotubes between neurons enable the spread of Parkinson's disease via lysosomes | Amazing Science | Scoop.it

Scientists from the Institut Pasteur have demonstrated the role of lysosomal vesicles in transporting α-synuclein aggregates, responsible for Parkinson's and other neurodegenerative diseases, between neurons. These proteins move from one neuron to the next in lysosomal vesicles which travel along the "tunneling nanotubes" between cells. These findings were published in The EMBO Journal on Aug. 22, 2016.

 

Synucleinopathies, a group of neurodegenerative diseases including Parkinson's disease, are characterized by the pathological deposition of aggregates of the misfolded α-synuclein protein into inclusions throughout the central and peripheral nervous system. Intercellular propagation (from one neuron to the next) of α-synuclein aggregates contributes to the progression of the neuropathology, but little was known about the mechanism by which spread occurs.

 

In this study, scientists from the Membrane Traffic and Pathogenesis Unit, directed by Chiara Zurzolo at the Institut Pasteur, used fluorescence microscopy to demonstrate that pathogenic α-synuclein fibrils travel between neurons in culture, inside lysosomal vesicles through tunneling nanotubes (TNTs), a new mechanism of intercellular communication.

 

After being transferred via TNTs, α-synuclein fibrils are able to recruit and induce aggregation of the soluble α-synuclein protein in the cytosol of cells receiving the fibrils, thus explaining the propagation of the disease. The scientists propose that cells overloaded with α-synuclein aggregates in lysosomes dispose of this material by hijacking TNT-mediated intercellular trafficking. However, this results in the disease being spread to naive neurons.

 

This study demonstrates that TNTs play a significant part in the intercellular transfer of α-synuclein fibrils and reveals the specific role of lysosomes in this process. This represents a major breakthrough in understanding the mechanisms underlying the progression of synucleinopathies.

 

These compelling findings, together with previous reports from the same team, point to the general role of TNTs in the propagation of prion-like proteins in neurodegenerative diseases and identify TNTs as a new therapeutic target to combat the progression of these incurable diseases.

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The mystery of why you can't remember being a baby

The mystery of why you can't remember being a baby | Amazing Science | Scoop.it

From the most dramatic moment in life – the day of your birth – to first steps, first words, first food, right up to nursery school, most of us can’t remember anything of our first few years. Even after our precious first memory, the recollections tend to be few and far between until well into our childhood. How come?

This gaping hole in the record of our lives has been frustrating parents and baffling psychologists, neuroscientists and linguists for decades. It was a minor obsession of the father of psychotherapy, Sigmund Freud, who coined the phrase ‘infant amnesia’ over 100 years ago.

 

Probing that mental blank throws up some intriguing questions. Did your earliest memories actually happen, or are they simply made up? Can we remember events without the words to describe them? And might it one day be possible to claim your missing memories back?


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Abundant Oxygen Measured in a 12-Billion-Year-Old Galaxy

Abundant Oxygen Measured in a 12-Billion-Year-Old Galaxy | Amazing Science | Scoop.it

UCLA astronomers have made the first accurate measurement of the abundance of oxygen in a distant galaxy. Oxygen, the third-most abundant chemical element in the universe, is created inside stars and released into interstellar gas when stars die. Quantifying the amount of oxygen is key to understanding how matter cycles in and out of galaxies.

 

This research is published online in the Astrophysical Journal Letters, and is based on data collected at the W. M. Keck Observatory on Mauna Kea, in Hawaii.

 

"This is by far the most distant galaxy for which the oxygen abundance has actually been measured," said Alice Shapley, a UCLA professor of astronomy, and co-author of the study. "We're looking back in time at this galaxy as it appeared 12 billion years ago."

Knowing the abundance of oxygen in the galaxy called COSMOS-1908 is an important stepping stone toward allowing astronomers to better understand the population of faint, distant galaxies observed when the universe was only a few billion years old and galaxy evolution, Shapley said.


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NASA: July 2016 was the warmest July in 136 years of modern record-keeping

NASA: July 2016 was the warmest July in 136 years of modern record-keeping | Amazing Science | Scoop.it

July 2016 was the warmest July in 136 years of modern record-keeping, according to a monthly analysis of global temperatures by scientists at NASA's Goddard Institute for Space Studies (GISS) in New York.

 

Because the seasonal temperature cycle peaks in July, it means July 2016 also was warmer than any other month on record. July 2016's temperature was a statistically small 0.1 degrees Celsius warmer than previous warm Julys in 2015, 2011 and 2009.

“It wasn't by the widest of margins, but July 2016 was the warmest month since modern record keeping began in 1880,” said GISS Director Gavin Schmidt. “It appears almost a certainty that 2016 also will be the warmest year on record.”

 

The record warm July continued a streak of 10 consecutive months dating back to October 2015 that have set new monthly high-temperature records. Compared to previous years, the warmer global temperatures last month were most pronounced in the northern hemisphere, particularly near the Arctic region.

The monthly analysis by the GISS team is assembled from publicly available data acquired by about 6,300 meteorological stations around the world, ship- and buoy-based instruments measuring sea surface temperature, and Antarctic research stations. The modern global temperature record begins around 1880 because previous observations didn't cover enough of the planet.

Related LinksFor more information on NASA GISS's monthly temperature analysis, visit: data.giss.nasa.gov/gistemp.

For more information about NASA GISS, visit: www.giss.nasa.gov.

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Rainbow galaxies reveal why cosmos is full of spirals

Rainbow galaxies reveal why cosmos is full of spirals | Amazing Science | Scoop.it

Psychedelic pictures of 30 galactic collisions show for the first time that merging galaxies often spawn disc-shaped offspring like our Milky Way.

 

These images show the carbon monoxide gas detected in neighboring galaxies – 40 to 600 million light years from Earth – in their final stages of merging. The colors show how this gas was moving: blue represents gas that is moving towards us, while red indicates gas that is moving away.

 

Out of 37 galaxies observed, these 30 all show gas rotating around the centre of the galaxy, meaning they are disc galaxies in the making.

 

“For the first time there is observational evidence for merging galaxies that could result in disc galaxies. This is a large and unexpected step towards understanding the mystery of the birth of disc galaxies,” says Junko Ueda from the Japan Society for the Promotion of Science. Ueda and her team made the observations using data from the ALMA radio telescope.

Computer simulations suggested that when galaxies merge, they usually form a single blob-shaped galaxy classed as “elliptical”. However, most of the galaxies in the universe are pancake-shaped “disc” galaxies, such as lenticular galaxies and our own spiral Milky Way. As this rogues’ gallery of galactic mergers shows, a disc-shaped offspring is a common result of a collision.

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