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Hubble spots largest known population of star clusters -- about 160,000 of them

Hubble spots largest known population of star clusters -- about 160,000 of them | Amazing Science |

NASA’s Hubble space telescope has discovered the largest known population of globular star clusters — an estimated 160,000 — more than two billion light years away from Earth. The galaxies are swarming like bees inside the crowded core of the giant grouping of galaxies Abell 1689. By comparison, our Milky Way galaxy hosts about 150 such clusters.


The Hubble observations also confirm that these compact stellar groupings can be used as reliable tracers of the amount of dark matter locked away in immense galaxy clusters. Globular clusters, dense bunches of hundreds of thousands of stars, are the homesteaders of galaxies, containing some of the oldest surviving stars in the universe.


An international team of astronomers, led by John Blakeslee of the National Research Council, Herzberg Astrophysics Programme at the Dominion Astrophysical Observatory in Victoria, British Columbia, Canada, discovered a bounty of these stellar fossils, which is roughly twice as large as any other population found in previous globular cluster surveys.


The Hubble observations also win the distance record for the farthest such systems ever studied, at 2.25 billion light-years away, researchers said.

The research team found that the globular clusters are intimately intertwined with dark matter.


“In our study of Abell 1689, we show how the relationship between globular clusters and dark matter depends on the distance from centre of the galaxy grouping,” said team member Karla Alamo-Martinez of the Centre for Radio Astronomy and Astrophysics of the National Autonomous University of Mexico in Morelia.


“In other words, if you know how many globular clusters are within a certain distance, we can give you an estimate of the amount of dark matter,” said Alamo-Martinez. The Hubble study shows that most of the globular clusters in Abell 1689 formed near the centre of the galaxy cluster, which contains a deep well of dark matter.

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Examples of quantum mechanics that can be seen in every-day life

Examples of quantum mechanics that can be seen in every-day life | Amazing Science |

The weird effects that show up in quantum mechanics (a lot of them anyway) are due to the wave-nature of the world making itself more apparent.  What we normally think of as “particle behavior” is just what happens when the waves you’re talking about are very small (compared to what’s around) and are “decoherent” (which means the frequency, phase and polarization are all pretty random between one photon and the next).  It’s a long way from obvious (there’s some math) but, for example, the way light streams through gaps is governed entirely by the wave-nature of light, and not because it’s a particle.


In addition to light’s waviness, it also has polarization (which is a fundamentally not-particle thing to have).  The polarization of light affects how it reflects off of a surface (like water) and how it scatters in a gas (like air).  If you happen to look at the sky reflecting off of a lake these effects are combined, and at one particular angle they fight each other. The amount of light that reflects off of a surface depends on the polarization of that light, which is why polarized glasses are sold to drivers to cut down on glare.  It so happens that if vertically polarized light hits water at about 37° none of it will be reflected (this is called “Brewster’s angle“).


Because of the way light scatters in air, if you point your hand at any point in the sky (other than the Sun), and turn your palm toward the Sun, then the flat of your hand will be aligned with the polarization of the light coming from that part of the sky.  As a result, right around dawn and dusk the entire sky is polarized in the north-south direction.


One consequence of this is that if you’re standing at the right angle early or late in the day, and the sky (not the Sun) is your primary light source, then the face on your digital watch can appear black.  Another is that if you look at the sky in a still lake, at about 37° from level, during dawn or dusk, while looking either north or south, you’ll find that the sky isn’t reflected at all and appears black.



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Nanomal smartphone-like malaria detection device to be field tested one year earlier than scheduled

Nanomal smartphone-like malaria detection device to be field tested one year earlier than scheduled | Amazing Science |

A pioneering mobile device using cutting-edge nanotechnology to rapidly detect malaria infection and drug resistance will be ready for field testing this year, one year ahead of schedule.


The €5.2million (£4million) Nanomal project was launched last year to provide an affordable hand-held diagnostic device to detect malaria infection and parasites’ drug resistance in 15 minutes. It will allow healthcare workers in remote rural areas to deliver effective drug treatments to counter resistance more quickly, potentially saving lives.


The news that the project is a year ahead of schedule comes on World Malaria Day today (25 April), as the World Health Organization warns of the alarming growth of resistance to drug treatments.


Nanomal lead Professor Sanjeev Krishna, from St George’s, said: “Recent research suggests there’s a real danger that current artemisinin combination therapies could eventually become obsolete, in the same way as other anti-malarials. This risk is worsened when patients presenting with a fever are given anti-malarial drugs without an analysis of the malaria parasites’ drug resistance status, or even without a diagnostic test at all, thereby reducing the treatments’ effectiveness.”


The Nanomal device is being developed by St George’s, University of London and Newcastle-based QuantuMDx Group. It will use a range of novel nanotechnologies to rapidly analyse the malarial DNA from a finger-prick of blood. The sample will be processed and a nanowire biosensor will detect DNA sequences of interest. This will provide a malaria diagnosis, speciation and drug resistance information in 15 minutes, allowing an effective personalised drug combination to be given immediately. The smartphone-like device will be easy to use; a healthcare worker simply puts the sample into the device, presses a few buttons and waits for the result, making it ideal for use in the field.


QuantuMDx’s CEO Elaine Warburton said: “Placing a full malaria screen with drug resistance status in the palm of a health professional’s hand will allow instant prescribing of the most effective anti-malaria medication for that patient. Nanomal’s rapid, low-cost test will further support the global health challenge to eradicate malaria.”


The device aims to provide the same quality of result as a referral laboratory, at a fraction of the time and cost. Each device could cost about the price of a smartphone initially, but may be distributed free in developing countries. A single-test cartridge will be around $13 (£10) initially, but the goal is to reduce this cost to ensure affordability in resource-limited settings.


In addition to improving immediate patient outcomes, the project will allow the researchers to build a better picture of levels of drug resistance in stricken areas. It will also give them information on population impacts of anti-malarial interventions. The technology could also be adapted afterwards for use with other infectious diseases.

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New connection between stacked solar cells can handle energy of 70,000 suns

New connection between stacked solar cells can handle energy of 70,000 suns | Amazing Science |

North Carolina State University researchers have come up with a new technique for improving the connections between stacked solar cells, which should improve the overall efficiency of solar energy devices and reduce the cost of solar energy production. The new connections can allow these cells to operate at solar concentrations of 70,000 suns worth of energy without losing much voltage as "wasted energy" or heat.

Stacked solar cells consist of several solar cells that are stacked on top of one another. Stacked cells are currently the most efficient cells on the market, converting up to 45 percent of the solar energy they absorb into electricity.


But to be effective, solar cell designers need to ensure the connecting junctions between these stacked cells do not absorb any of the solar energy and do not siphon off the voltage the cells produce—effectively wasting that energy as heat.


"We have discovered that by inserting a very thin film of gallium arsenide into the connecting junction of stacked cells we can virtually eliminate voltage loss without blocking any of the solar energy," says Dr. Salah Bedair, a professor of electrical engineering at NC State and senior author of a paper describing the work.


This work is important because photovoltaic energy companies are interested in using lenses to concentrate solar energy, from one sun (no lens) to 4,000 suns or more. But if the solar energy is significantly intensified—to 700 suns or more—the connecting junctions used in existing stacked cells begin losing voltage. And the more intense the solar energy, the more voltage those junctions lose—thereby reducing the conversion efficiency.


"Now we have created a connecting junction that loses almost no voltage, even when the stacked solar cell is exposed to 70,000 suns of solar energy," Bedair says. "And that is more than sufficient for practical purposes, since concentrating lenses are unlikely to create more than 4,000 or 5,000 suns worth of energy. This discovery means that solar cell manufacturers can now create stacked cells that can handle these high-intensity solar energies without losing voltage at the connecting junctions, thus potentially improving conversion efficiency.


"This should reduce overall costs for the energy industry because, rather than creating large, expensive solar cells, you can use much smaller cells that produce just as much electricity by absorbing intensified solar energy from concentrating lenses. And concentrating lenses are relatively inexpensive," Bedair says.

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Unusual Mechanism of DNA Synthesis Could Explain Certain Genetic Mutations

Unusual Mechanism of DNA Synthesis Could Explain Certain Genetic Mutations | Amazing Science |
Researchers have discovered how cells repair a potentially devastating kind of DNA damage.


The repair of chromosomal double strand breaks (DSBs) is crucial for the maintenance of genomic integrity. However, the repair of DSBs can also destabilize the genome by causing mutations and chromosomal rearrangements, the driving forces for carcinogenesis and hereditary diseases.


Break-induced replication (BIR) is one of the DSB repair pathways that is highly prone to genetic instability. BIR proceeds by invasion of one broken end into a homologous DNA sequence followed by replication that can copy hundreds of kilobases of DNA from a donor molecule all the way through its telomere. The resulting repaired chromosome comes at a great cost to the cell, as BIR promotes mutagenesis, loss of heterozygosity, translocations, and copy number variations, all hallmarks of carcinogenesis. BIR uses most known replication proteins to copy large portions of DNA, similar to S-phase replication. It has therefore been suggested that BIR proceeds by semiconservative replication; however, the model of a bona fide, stable replication fork contradicts the known instabilities associated with BIR such as a 1,000-fold increase in mutation rate compared to normal replication.


The collaborative work of graduate students working under Anna Malkova, associate professor of biology at Indiana University-Purdue University Indianapolis (IUPUI) and Kirill Lobachev, associate professor of biology at the Georgia Institute of Technology have now discovered that in budding yeast the mechanism of replication during BIR is significantly different from S-phase replication, as it proceeds via an unusual bubble-like replication fork that results in conservative inheritance of the new genetic material. They provide evidence that this atypical mode of DNA replication, dependent on Pif1 helicase, is responsible for the marked increase in BIR-associated mutations.


Lobachev’s lab used cutting-edge analysis techniques and equipment available at only a handful of labs around the world. This allowed the researchers to see inside yeast cells and freeze the break-induced DNA repair process at different times. They found that this mode of DNA repair doesn’t rely on the traditional replication fork — a Y-shaped region of a replicating DNA molecule — but instead uses a bubble-like structure to synthesize long stretches of missing DNA. This bubble structure copies DNA in a manner not seen before in eukaryotic cells.


Traditional DNA synthesis, performed during the S-phase of the cell cycle, is done in semi-conservative manner as shown by Matthew Meselson and Franklin Stahl in 1958 shortly after the discovery of the DNA structure. They found that two new double helices of DNA are produced from a single DNA double helix, with each new double helix containing one original strand of DNA and one new strand.


“We demonstrated that break-induced replication differs from S-phase DNA replication as it is carried out by a migrating bubble instead of a normal replication fork and leads to conservative DNA synthesis promoting highly increased mutagenesis,” Malkova said.


This desperation replication triggers “bursts of genetic instability” and could be a contributing factor in tumor formation. “From the point of view of the cell, the whole idea is to survive, and this is a way for them to survive a potentially lethal event, but it comes at a cost,” Lobachev said. “Potentially, it’s a textbook discovery.”


During break-induced replication, one broken end of DNA is paired with an identical DNA sequence on its partner chromosome. Replication that proceeds in an unusual bubble-like mode then copies hundreds of kilobases of DNA from the donor DNA through the telomere at the ends of chromosomes.


“Surprisingly, this is a way of synthesizing DNA in a very robust manner,” Saini said. “The synthesis can take place and cover the whole arm of the chromosome, so it’s not just some short patches of synthesis.”


The bubble-like mode of DNA replication can operate in non-dividing cells, which is the state of most of the body’s cells, making this kind of replication a potential route for cancer formation. “Importantly, the break-induced replication bubble has a long tail of single-stranded DNA, which promotes mutations,” Ramakrishnan said.


The single-stranded tail might be responsible for the high mutation-rate because it can accumulate mutations by escaping the other repair mechanisms that quickly detect and correct errors in DNA synthesis. “When it comes to cancer, other diseases and even evolution, what seems to be happening are bursts of instability, and the mechanisms promoting such bursts were unclear,” Malkova said.


The molecular mechanism of break-induced replication unraveled by the new study provides one explanation for the generation of mutations. We propose that the BIR mode of synthesis presents a powerful mechanism that can initiate bursts of genetic instability in eukaryotes, including humans.

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Analysis of Sutter's Mill meteorite fragments reveals organic compounds not seen before

Analysis of Sutter's Mill meteorite fragments reveals organic compounds not seen before | Amazing Science |
( —A team of researchers from Arizona State University has found that the space rock known as the Sutter's Mill meteorite had organic compounds in it that have not been found in any other known meteorite.


Sutter's Mill meteorite was seen streaking through the atmosphere above northern California in April 2012. That led to a search by many interested parties for the chunks that survived the intense heat and made their way to the Earth's surface—in all 77 rocks were found and turned over to scientists eager to study their composition—initial testing of some of the specimens revealed few dissoluble organic compounds. Undaunted, the researchers took another approach, applying hydrothermal treatment—a process that is meant to mimic the conditions scientists believe existed on certain parts of the Earth during the time life first emerged. This time, the team reports, the fragments released organic compounds that had never before been seen in a meteorite.


Organic compounds in meteorites (most of which are believed to come from the asteroid belt between Jupiter and Mars) are important to researchers who believe it's possible that life got its start here on Earth thanks to meteorites that carried payloads that added to material found on Earth. Taken together, the ingredients made for the perfect cocktail, eventually giving rise to the mysterious process that resulted in the creation of living organic matter and eventually all the forms of life that came after.


Looking to meteorites as a possible source for life on Earth has come about due to scientists' inability to nail down a rational explanation for the development of life based on theories of how the Earth came to exist. Of course, such theories only move the debate to another arena—if life came here from somewhere else, how did it get started in that other place? Scientists have no answer, but hope studying rocks brought from space will offer clues that may help to someday solve the puzzle.

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UCI-led Study Show Evidence That Memories Can be Created By Direct Manipulation Of The Brain

UCI-led Study Show Evidence That Memories Can be Created By Direct Manipulation Of The Brain | Amazing Science |
By studying how memories are made, UC Irvine neurobiologists created new, specific memories by direct manipulation of the brain, which could prove key to understanding and potentially resolving learning and memory disorders.


Research led by senior author Norman M. Weinberger, a research professor of neurobiology & behavior at UC Irvine, and colleagues has shown that specific memories can be made by directly altering brain cells in the cerebral cortex, which produces the predicted specific memory. The researchers say this is the first evidence that memories can be created by direct cortical manipulation.

During the research, Weinberger and colleagues played a specific tone to test rodents then stimulated the nucleus basalis deep within their brains, releasing acetylcholine (ACh), a chemical involved in memory formation. This procedure increased the number of brain cells responding to the specific tone. The following day, the scientists played many sounds to the animals and found that their respiration spiked when they recognized the particular tone, showing that specific memory content was created by brain changes directly induced during the experiment. Created memories have the same features as natural memories including long-term retention.


"Disorders of learning and memory are a major issue facing many people and since we've found not only a way that the brain makes memories, but how to create new memories with specific content, our hope is that our research will pave the way to prevent or resolve this global issue," said Weinberger, who is also a fellow with the Center for the Neurobiology of Learning & Memory and the Center for Hearing Research at UC Irvine.


The creation of new memories by directly changing the cortex is the culmination of several years of research in Weinberger's lab implicating the nucleus basalis and ACh in brain plasticity and specific memory formation. Previously, the authors had also shown that the strength of memory is controlled by the number of cells in the auditory cortex that process a sound.

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Elon Musk designs real-world gesture interface and 3D modeler

Elon Musk designs real-world gesture interface and 3D modeler | Amazing Science |

Elon Musk manipulates 3D object with hand gestures (Credit: SpaceX) Elon Musk has released a video demonstrating SpaceX's new custom 3D design interface.


After generating and manipulating the 3D model, Musk then 3D-prints an actual titanium metallic rocket-engine part from the model. “I believe we are on the verge of a major breakthrough in design manufacturing, in being able to take the concept of something from your mind, translate that into a 3D object, really intuitively on the computer, and than take that virtual 3D object and be able to make it real just by printing it,” says Musk in the impressive video.

“So it is going to revolutionize design manufacturing in the 21st century.”

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Astrobiology Roadmap 2013/2014 - Webinars

Astrobiology Roadmap 2013/2014 - Webinars | Amazing Science |

1. Early Evolution of Life

2. Planetary Conditions for Life

3. Evolution of Advanced Life

4. Prebiotic Evolution

5. Solar Systems Exploration

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How to use DNA to assemble a transistor from graphene

How to use DNA to assemble a transistor from graphene | Amazing Science |

Stanford chemical engineering professor Zhenan Bao and her co-authors have revealed a plan to build smaller field-effect transistors (FETs) that use less power but operate faster,* using ribbons of single-layer graphene laid side-by-side to create semiconductor circuits.


(Graphene, laterally confined within narrow ribbons less than 10 nanometers in width, exhibits a bandgap, meaning it can function as a semiconductor.)

Given the material’s tiny dimensions and favorable electrical properties, graphene nano ribbons could create very fast chips that run on very low power, she said.


“However, as one might imagine, making something that is only one atom thick and 20 to 50 atoms wide is a significant challenge,” said co-author former post-doctoral fellow Anatoliy Sokolovco.


To handle this challenge, the Stanford team came up with the idea of using DNA as an assembly mechanism. Physically, DNA strands are long and thin, and exist in roughly the same dimensions as the graphene ribbons that researchers wanted to assemble. Chemically, DNA molecules contain carbon atoms, the material that forms graphene.


Here’s how Bao and her team put DNA’s physical and chemical properties to work:


1. The researchers started with a tiny platter of silicon to provide a support (substrate) for their experimental transistor. They dipped the silicon platter into a solution of DNA derived from bacteria and used a known technique to comb the DNA strands into relatively straight lines.


2. Next, the DNA on the platter was exposed to a copper salt solution. The chemical properties of the solution allowed the copper ions to be absorbed into the DNA.


3. Next the platter was heated and bathed in methane gas, which contains carbon atoms. Once again chemical forces came into play to aid in the assembly process. The heat sparked a chemical reaction that freed some of the carbon atoms in the DNA and methane. These free carbon atoms quickly joined together to form stable honeycombs of graphene.


“The loose carbon atoms stayed close to where they broke free from the DNA strands, and so they formed ribbons that followed the structure of the DNA,” Yap said. “We demonstrated for the first time that you can use DNA to grow narrow ribbons and then make working transistors,” Sokolov said.


Bao said the assembly process needs a lot of refinement. For instance, not all of the carbon atoms formed honeycombed ribbons a single atom thick. In some places they bunched up in irregular patterns, leading the researchers to label the material graphitic instead of graphene.


Even so, the process, about two years in the making, points toward a strategy for turning this carbon-based material from a curiosity into a serious contender to succeed silicon.

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Farmer ants draft parasite ants as mercenaries

Farmer ants draft parasite ants as mercenaries | Amazing Science |

Farmer ants can recruit parasites to battle for them, much like medieval cities sometimes kept expensive contingents of mercenary soldiers to ward off invaders, researchers say.


The finding highlights that parasites might not always be a bad thing, underscoring the complex relationships between species in nature, investigators added.


Scientists investigated ants in Panama named Sericomyrmex, which raise fungus in gardens. The farmer ants are regularly beset by parasitic ants named Megalomyrmex. Queens of Megalomyrmex stealthily enter and colonize the gardens of Sericomyrmex and can feed on their offspring and their fungus for years. They also clip the wings of the virgin queens of the farmers, hampering the spread of Sericomyrmex colonies.


Evolutionary biologist Rachelle Adams at the University of Copenhagen had studiedMegalomyrmex for more than a decade when she noticed they were remarkably common compared with other parasitic species, at times making up than 80 percent of some host populations.

"This prompted me to question why this might be, leading me to focus my collecting efforts on this particular system," Adams said. The researchers focused on the potent venom produced by Megalomyrmex. To see what effects it had, Adams and her colleagues exposed these parasites to ants named Gnamptogenys, which can usurp the gardens of the farmer ants, Sericomyrmex, and quickly devastate their nests.


The results surprised the scientists. The farmer ants hid while the parasites rose to confront the invading Gnamptogenysants, killing them better than the bites of the farmers could. The parasites acted as soldiers for their hosts, since the raiders would harm the parasites' interests — the hosts that the parasites want to exploit. This benefit helps explain why these parasites are so common among some of the farmer ant populations.


"The guest ants are the better of two evils," Adams told LiveScience. "If the raiders were not a threat, then the guest ants would only be a burden to the host colony." Indeed, experiments revealed that when it came to marshaling forces to assault farmers, scouts of the raiders preferred colonies that did not smell of the parasites.


"If we studied just the farming ants and the guest ants, we would have missed this important discovery and concluded the guest ants are simply parasites," Adams said. The researchers compared this tradeoff to sickle cell anemia, a hereditary blood disease that can cut lives short but also gives people resistance against malaria.

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Recording and replaying human touch: The next user-interface revolution?

Recording and replaying human touch: The next user-interface revolution? | Amazing Science |
Researchers at the University of California, San Diego report a breakthrough in technology that could pave the way for digital systems to record, store, edit and replay information in a dimension that goes beyond what we can see or hear: touch.


“Touch was largely bypassed by the digital revolution, except for touch-screen displays, because it seemed too difficult to replicate what analog haptic devices – or human touch – can produce,” said Deli Wang, a professor of Electrical and Computer Engineering (ECE) in UC San Diego’s Jacobs School of Engineering. “But think about it: being able to reproduce the sense of touch in connection with audio and visual information could create a new communications revolution.”


In addition to uses in health and medicine, the communication of touch signals could have far-reaching implications for education, social networking, e-commerce, robotics, gaming, and military applications, among others. The sensors and sensor arrays reported in the paper are also fully transparent (see optical image of transparent ZnO TFT sensor array at right), which makes it particularly interesting for touch-screen applications in mobile devices.


Digital replay, editing and manipulation of recorded touch events were demonstrated at various spatial and temporal resolutions. The researchers used an 8 × 8 active-matrix ZnO pressure sensor array, a data acquisition and processing system (sensor array reader circuit, computer, and actuator array driver circuit), and a semi-rigid 8 × 8 polymer diaphragm actuator array.


The ability to digitize the touch contact enables direct remote transfer of touch information, long-term memory storage, and replay at a later time. “In addition, with the ability to reproduce and change the feeling of touch with both temporal and spatial resolutions make it possible to produce synthesized touch,” said UC San Diego’s Wang. “It could create experiences that do not exist in nature, as we have done with computer-generated imagery and synthesized music.”


While Wang and his colleagues recognize that the touch revolution is still in its infancy, and human trials will probably be needed to calibrate the optimal actuator response needed to conform to the human perception of pressure strength, which depends on actuator displacement (amplitude), frequency, and how much time the actuator spends in its on- or off-state (duty cycle). Yet, say the researchers, there is every reason to believe that their experimental system, by adding an extra dimension to existing digital technologies, could extend the capabilities of modern information exchange.

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The Art of Science: Supercomputers Help Scientists See What Microscopes and Cameras Can’t Capture

The Art of Science: Supercomputers Help Scientists See What Microscopes and Cameras Can’t Capture | Amazing Science |

sts at GE Global Research have been using the world’s most powerful supercomputers to simulate everything from fuel flowing through jet engine nozzles to water drops turning into ice. The results can be rewarding beyond solving research riddles. “Many times our work generates images that are visually breathtaking,” says Rick Arthur, who leads the Advanced Computing Lab at GRC.


Supercomputers are helping GE engineers speed up innovation, crack previously intractable problems, and shorten the business cycle. Take a look at our slideshow featuring a hypnotizing turbine flow, density gradients and other arresting images generated by GRC scientists.

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Wide range of differences, mostly unseen, among humans: Silent mutations more significant than expected

Wide range of differences, mostly unseen, among humans: Silent mutations more significant than expected | Amazing Science |

No two human beings are the same. Although we all possess the same genes, our genetic code varies in many places. And since genes provide the blueprint for all proteins, these variants usually result in numerous differences in protein function. But what impact does this diversity have? Bioinformatics researchers at Rutgers University and the Technische Universitaet Muenchen (TUM) have investigated how protein function is affected by changes at the DNA level. Their findings bring new clarity to the wide range of variants, many of which disturb protein function but have no discernible health effect, and highlight especially the role of rare variants in differentiating individuals from their neighbors.

The slightest changes in human DNA can result in an incorrect amino acid being incorporated into a protein. In some cases, all it takes is for a single base to be substituted in a person's DNA, a variant known as a single nucleotide polymorphism (SNP). "Many of these pointmutations have no impact on human health. However, of the roughly 10,000 'missense' SNPs in the human genome – that is, SNPs affecting the protein sequence – at least a fifth can change the function of the protein," explains Prof. Yana Bromberg of the Department of Biochemistry and Microbiology at Rutgers University. "And in some cases, the affected protein is so important and the change so large that we have to wonder why the person with this mutation is still healthy."

Furthermore, two unrelated individuals have thousands of different mutations that affect proteins. Previously, scientists did not fully understand how this large number of mutations affects the coding sequences of DNA. To investigate these "silent" mutations, Bromberg joined forces with Rutgers colleague Prof. Peter Kahn and Prof. Burkhard Rost at TUM.

"We found that many of the mutations are anything but silent," declares Rost, head of the TUM Chair for Bioinformatics and a fellow of the TUM Institute for Advanced Study. The research indicates an extremely wide range of mutations. Many SNPs, for example, are neutral and do not affect protein function. Some, however, cause pathogenic disruption to protein functionality. "There is a gray area between these extremes," Rost explains. "Some proteins have a reduced biological function but are tolerated by the organism and therefore do not directly trigger any disease."


The research team analyzed over one million SNPs from a number of DNA databases. They used artificial learning methods to simulate the impact of DNA mutations on the function of proteins. This approach enabled them to investigate the impact of a large number of SNPs quickly and efficiently.


The study's findings suggest that, with respect to diversity in protein function, the individual differences between two people are greater than previously assumed. "It seems that humans can live with many small changes in protein function," says Rost. One conclusion the researchers draw is that the wide functional spectrum of proteins must play a key role in evolution. In addition, Bromberg says, "Protein functional diversity may also hold the key to developing personalized medicine."

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Rising Seas - Interactive: Explore the Coast Lines If All The Ice Melted

Rising Seas - Interactive: Explore the Coast Lines If All The Ice Melted | Amazing Science |

The maps here show the world as it is now, with only one difference: All the ice on land has melted and drained into the sea, raising it 216 feet and creating new shorelines for our continents and inland seas.

There are more than five million cubic miles of ice on Earth, and some scientists say it would take more than 5,000 years to melt it all. If we continue adding carbon to the atmosphere, we’ll very likely create an ice-free planet, with an average temperature of perhaps 80 degrees Fahrenheit instead of the current 58.

Via Kathy Bosiak
Amy Odlum's curator insight, September 21, 2013 4:32 PM

Year 8 Geog - Climate Change

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An extinct species of tool-making humans occupied a vast area in China as early as 1.7 million years ago

An extinct species of tool-making humans occupied a vast area in China as early as 1.7 million years ago | Amazing Science |
The artifacts studied may belong to Homo erectus and suggest the now-extinct human species migrated to China 700,000 years earlier than thought. Such hominid migrations to East Asia may have been due to cooling and aridity in Africa and Eurasia.


The human lineage evolved in Africa, with now-extinct species of humans dispersing away from their origin continent more than a million years before modern humans did. Scientists would like tolearn more about when and where humans went to better understand what drove human evolution.


Researchers investigated the Nihewan Basin, which lies in a mountainous region about 90 miles (150 kilometers) west of Beijing. It holds more than 60 sites from the Stone Age, with thousands of stone tools found there since 1972 — relatively simple types, such as stone flakes altogether known as the Oldowan. Researchers suspect these artifacts belonged to Homo erectus, "thought to be ancestral to Homo sapiens," Hong Ao, a paleomagnetist at the Chinese Academy of Sciences in Xi'an, told LiveScience.


The exact age of these sites was long uncertain. To find out, Ao and his colleagues analyzed the earth above, below and in which stone tools at the Shangshazui site in the Nihewan Basin were found. The tools in question were stone blades potentially used for cutting or scraping.


The scientists analyzed the way in which the samples of earth were magnetized — since the Earth's magnetic field has regularly flippednumerous times over millions of years, looking at the manner in which the magnetic fields of minerals are oriented can shed light on how old they are. The researchers discovered this site in northern China might be about 1.6 million to 1.7 million years old, making it 600,000 or 700,000 years older than previously thought.


Horse, elephant and other fossils suggest the area back when the stone tools were made was mainly grassland interspersed with patches of woodland. A lake between the mountains there was probably a major attraction for hominid explorers, providing water and a range of other food sources, while the mountains could have represented an important material source for making stone tools. The researchers suggest hominid migrations to East Asia during the early Stone Age were a consequence of increasing cooling and aridity in Africa and Eurasia.


Given that slightly older artifacts and bones belonging to Homo erectuswere previously discovered in southern China more than 1,500 miles (2,500 km) away, these new findings suggest early and now-extinct human species may potentially have occupied a huge territory in China.


"Homo erectus occupied a vast area in China by 1.7 million to 1.6 million years ago," Ao said.

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Made-to-order materials: Engineers focus on the nano to create strong, lightweight materials

Made-to-order materials: Engineers focus on the nano to create strong, lightweight materials | Amazing Science |

The lightweight skeletons of organisms such as sea sponges display a strength that far exceeds that of manmade products constructed from similar materials. Scientists have long suspected that the difference has to do with the hierarchical architecture of the biological materials—the way the silica-based skeletons are built up from different structural elements, some of which are measured on the scale of billionths of meters, or nanometers. Now engineers at the California Institute of Technology (Caltech) have mimicked such a structure by creating nanostructured, hollow ceramic scaffolds, and have found that the small building blocks, or unit cells, do indeed display remarkable strength and resistance to failure despite being more than 85 percent air.

Via Alin Velea
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Scientists manage to study the physics that connect the classical the quantum world

Scientists manage to study the physics that connect the classical the quantum world | Amazing Science |
How does a classical temperature form in the quantum world? An experiment at the Vienna University of Technology has directly observed the emergence and the spreading of a temperature in a quantum system.


The connection between the microscopic world of quantum physics and our everyday experience, which is concerned with much larger objects, still remains puzzling. When a quantum system is measured, it is inevitably disturbed and some of its quantum properties are lost.


A cloud of atoms, for example, can be prepared in such away that each atom is simultaneously located at two different places, forming a perfect quantum superposition. As soon as the location of the atoms is measured, however, this superposition is destroyed. All that is left are atoms sitting at some well-defined places. They behave just as classical objects would.


In this case, the transition from quantum behavior to classical behavior is initiated by the measurement – a contact with the outside world. But what happens, if a quantum system is not influenced from the outside at all? Can classical properties still emerge?


"We are studying clouds consisting of several thousand atoms", explains Tim Langen, lead author of the study from Professor Jörg Schmiedmayer's research team at Vienna University of Technology. "Such a cloud is small enough to effectively isolate it from the rest of the world, but it is large enough to study how quantum properties are lost".


In the experiment, the atom clouds are split into two halves. After a certain time the two halves are compared to each other. In that way, the scientists can measure the amount of quantum mechanical connection between the clouds. Initially, this connection is perfect; all atoms are in a highly ordered quantum state. But as the cloud is a large object consisting of thousands of particles, this order does not remain for long.


As the atoms interact with each other, disorder begins to spread with a certain velocity. Atoms in the already disordered regions lose their quantum properties. A temperature can be assigned to them – just as in a classical gas. "The velocity with which the disorder spreads depends on the number of atoms", says Tim Langen. This defines a clear border between the regions which can be described by a classical temperature and regions where quantum properties remain unchanged.


After a certain time the disorder has spread over the whole cloud. The remarkable observation is that this loss of quantum properties happens just because of quantum effects inside the atom cloud, without any influence from the outside world. "So far, such a behavior had only been conjectured, but our experiments demonstrate that nature really behaves like this", Jörg Schmiedmayer points out.

In a way, the atomic cloud behaves like its own miniature universe. It is isolated from the environment, so its behavior is solely determined by its internal properties. Starting with a completely quantum mechanical state, the cloud looks "classical" after some time, even though it evolves according to the laws of quantum physics. That is why the experiment could not just help us to understand the behavior of large atom clouds, it could also help to explain, why the world that we experience every day looks so classical, even though it is governed by quantum laws.

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New dimensions on ice: Arctic winter ice continues to decline

New dimensions on ice: Arctic winter ice continues to decline | Amazing Science |
Offering new insights into our fragile polar regions, ESA’s CryoSat mission has provided three consecutive years of Arctic sea-ice thickness measurements, which show that the ice continues to thin.


Although satellites have witnessed a downward trend in the extent of sea ice over the last two decades, it is essential to have accurate information on the mass or volume of ice being lost. This is a more accurate measure of the changes taking place.


Along with observations of ice extent, CryoSat’s measurements of thickness now span from October 2010 to April 2013, allowing scientists to work out the real loss of ice, monitor seasonal change and identify trends. Prof. Andrew Shepherd from the University of Leeds, UK, said, “CryoSat continues to provide clear evidence of diminishing Arctic sea ice.


“From the satellite’s measurements we can see that some parts of the ice pack ice have thinned more rapidly than others, but there has been a decrease in the volume of winter and summer ice over the past three years.

“The volume of the sea ice at the end of last winter was less than 15 000 cubic km, which is lower than any other year going into summer and indicates less winter growth than usual.”


While it seems unlikely that a record minimum of sea-ice extent will be set this September, the thinner ice at the start of summer could mean that the actual volume of ice may reach a new low.


Rachel Tilling, PhD student at University College London, who is working with the CryoSat data stated, “Readings from CryoSat in October, when the ice starts to refreeze, will confirm this either way.”

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Quantum effects observed in nanowires at room temperature

Quantum effects observed in nanowires at room temperature | Amazing Science |

Nano technologists at the University of Twente research institute MESA+ have, for the first time, demonstrated quantum effects in tiny nanowires of iridium atoms. These effects, which occur at room temperature, are responsible for ensuring that the wires are almost always 4.8 nanometers—or multiples thereof—long. They only found the effects when they failed to create long nanowires of iridium.

There is an increasing interest in metallic nanowires within the scientific community. This is partly because they are extremely useful as part of (nano-) electronics and partly because nanowires lend themselves to achieving more insight into the exotic and unique physical properties of one-dimensional systems. In 2003, UT researcher, Prof. Harold Zandvliet and his research group, had already succeeded—using self-assembly—in creating nanowires of platinum atoms on a surface. Because gold and iridium are both closely related to platinum, nanowires of these materials were the following logical steps. The researchers managed to create long threads with gold, but when they recently wanted to repeat the trick with iridium, it appeared that the wire lengths occurred only in units of 4.8 nanometers.

Experiment failed, you might think, but that is not the case. Further examination of the nanowires formed produced namely a surprising discovery: nearly all the wires that were formed had a length of 4.8 nanometers, or multiples thereof, and they nearly all contained twelve iridium atoms, or a multiple thereof. The researchers found the explanation for this in quantum effects. The wires of 4.8 nanometers (or multiples thereof) appear to be electronically stabilized by conduction electrons whose (half) wavelength (or a multiple thereof) fits precisely in the nanowire. The existence of these standing electron waves in the nanowires could be demonstrated experimentally. As this stabilizing effect will not occur in nanowires of iridium of a different length, they are formed more slowly.


What makes quantum effects in the nanowires even more interesting is that they occur at room temperature, while many quantum effects normally appear only at extremely low temperatures.

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Dallol - The World's Weirdest Volcanic Crater

Dallol - The World's Weirdest Volcanic Crater | Amazing Science |

In the North East of Ethiopia lies the Danokil Desert.  At its heart is a volcanic crater, Dallol, little known and seldom visited but quite extraordinary.  

Surrounding the volcano are acidic hot springs, mountains of sulphur, pillars of salt, small gas geysers and pools of acid isolated by salt ridges. It makes for one of the most bizarre landscapes on planet Earth.

Dallol is effectively a volcanic explosion crater. It was formed when basaltic magma intruded in to salt deposits and water. This subsequently caused a huge phreatic eruption.  The rising magma made contact with the ground water. As magma is so extremely hot the water evaporated immediately.  The result was a huge explosion of rock, ash, water and steam – not to mention volcanic bombs (molten rock which cools and solidifies before it hits the ground).

The volcano last erupted in 1926 and gained some attention then but it had been known to Europeans for about two hundred years. Yet the site remained effectively unknown to most until recently – simply because of the hostile nature of the environment, the almost unbearable heat of the area and the very present danger from toxic fumes.

The volcano is surrounded by a huge saline area, the edges of which are studded with a multitude of fairy chimneys where gases have broken through. The sulphuric hot springs bubble at boiling point. The salt of the Danokil Depression, 136.8 meters below sea level, mixes with volcanic minerals such as sulfur, to create terraces and unique, other worldly concretions. Geysers and chimneys adorn the site throughout.

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Tomorrow's Cities: How may we be living in 2050 - a BBC report

Tomorrow's Cities: How may we be living in 2050 - a BBC report | Amazing Science |

Have you ever wondered where you or your children may be living in 2050? Experts predict that by then three-quarters of the world's population will live in cities. This August and September the BBC is taking a look at how our lives will be changed by the technological innovations being developed for Tomorrow’s Cities.

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Life found in the sediments of an Antarctic subglacial lake buried for over 100,000 years

Life found in the sediments of an Antarctic subglacial lake buried for over 100,000 years | Amazing Science |

The possibility that extreme life forms might exist in the cold and dark lakes hidden kilometers beneath the Antarctic ice sheet has fascinated scientists for decades.


However, direct sampling of these lakes in the interior of Antarctica continues to present major technological challenges. Recognising this, scientists from the British Antarctic Survey (BAS), and the Universities of Northumbria and Edinburgh have been searching around the retreating margins of the ice sheet for subglacial lakes that are becoming exposed for the first time since they were buried more than 100,000 years ago.


This is because parts of the ice sheet are melting and retreating at unprecedented rates as the temperature rises at the poles.


The group targeted Lake Hodgson on the Antarctic Peninsula which was covered by more than 400 m of ice at the end of the last Ice Age, but is now considered to be an emerging subglacial lake, with a thin covering of just 3–4 meters of ice.


Drilling through the ice they used clean coring techniques to delve into the sediments at the bottom of the lake which is 93 meters deep and approximately 1 mile long by 1.5 mile wide. The lake was thought to be a harsh environment for any form of life but the layers of mud at the bottom of the lake represent a time capsule storing the DNA of the microbes which have lived there throughout the millennia. The top few centimetres of the core contained current and recent organisms which inhabit the lake but once the core reached 3.2 meters deep the microbes found most likely date back nearly 100,000 years.


Lead author David Pearce, who was at BAS and is now at the University of Northumbria, says, “What was surprising was the high biomass and diversity we found. This is the first time microbes have been identified living in the sediments of a subglacial Antarctic lake and indicates that life can exist and potentially thrive in environments we would consider too extreme.


“The fact these organisms have survived in such a unique environment could mean they have developed in unique ways which could lead to exciting discoveries for us. This is the early stage and we now need to do more work to further investigate these life forms.”


Some of the life discovered was in the form of Fossil DNA showing that many different types of bacteria live there, including a range of extremophiles which are species adapted to the most extreme environments. These use a variety of chemical methods to sustain life both with and without oxygen.


One DNA sequence was related to the most ancient organisms known on Earth and parts of the DNA in twenty three percent has not been previously described. Many of the species are new to science making clean exploration of the remote lakes isolated under the deeper parts of the ice sheet even more pressing.


ate last year a British expedition to drill into Lake Ellsworth was called off after technical difficulties. A US expedition sampled a subglacial environment near the edge of the ice sheet but has yet to report its findings, and a Russian led project has sampled ice near the surface of a subglacial lake and has reported finding signs of life.

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3D faxing with the world's first all-in-one multifunction 3D printer / scanner

3D faxing with the world's first all-in-one multifunction 3D printer / scanner | Amazing Science |

The technology startup AIO Robotics has a prototype of an all-in-one 3D printer, scanner, copier and fax machine. The company states that it created a 3D printer with an integrated 3D scanner. The idea is to have an all-in-one 3D printer that is capable of 3D scanning, 3D printing, 3D copying, and 3D faxing.

The machine has a 7-inch color touchscreen with an on-board computer (ARM based) so the printer can totally work by itself without connection to a desktop computer. The on-board computer also handles 3D scanning data (HD camera pictures from a swiping laser) and uploads the data to the cloud for final 3D reconstruction."All linear components are made by CNC-machined aluminum (xyz-carrier, turntable) to ensure super rigid structure without any deforming and heat soaking. In addition, we also created an auto-bed leveling feature by integrating a Z-probe mechanism onto the extruder. This way, users don't need to calibrate the bed height at all. We will include a full API-package for developers to fully control all sensor and motors."

Although AIO Robotics have not finalized the pricing yet, the company says that it will be significantly cheaper than the Makerbot Replicator + Digitizer.

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Prion-like proteins drive several diseases of aging

Prion-like proteins drive several diseases of aging | Amazing Science |

Two leading neurology researchers have proposed a theory that could unify scientists’ thinking about several neurodegenerative diseases and suggest therapeutic strategies to combat them. The theory and backing for it are described in the September 5, 2013 issue of Nature.


Mathias Jucker and Lary Walker outline the emerging concept that many of the brain diseases associated with aging, such as Alzheimer’s and Parkinson’s, are caused by specific proteins that misfold and aggregate into harmful seeds. These seeds behave very much like the pathogenic agents known as prions, which cause mad cow disease, chronic wasting disease in deer, scrapie in sheep, and Creutzfeldt-Jakob disease in humans.


Walker is research professor at Yerkes National Primate Research Center, Emory University. Jucker is head of the Department of Cellular Neurology at the Hertie Institute for Clinical Brain Research at the University of Tübingen and the German Center for Neurodegenerative Diseases.


Unlike prion diseases, which can be infectious, Alzheimer’s, Parkinson’s, and other neurodegenerative diseases can not be passed from person to person under normal circumstances. Once all of these diseases take hold in the brain, however, it is increasingly apparent that the clumps of misfolded proteins spread throughout the nervous system and disrupt its function.


The authors were the first to show that a protein that is involved in Alzheimer’s disease – known as amyloid-beta – forms prion-like seeds that stimulate the aggregation of other amyloid-beta molecules in senile plaques and in brain blood vessels. Since then, a growing number of laboratories worldwide have discovered that proteins linked to other neurodegenerative disorders also share key features with prions.


Age-related neurodegenerative disorders remain stubbornly resistant to the discovery of effective treatments. Jucker and Walker propose that the concept of pathogenic protein seeding not only could focus research strategies for these seemingly unrelated diseases, but it also suggests that therapeutic approaches designed to thwart prion-like seeds early in the disease process could eventually delay or even prevent the diseases.

Monica S Mcfeeters's curator insight, March 15, 2014 11:07 PM

Don't have a file like this but I bet they used a lot of technology to find this!