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Diet Affects Men’s and Women’s Intestinal Microbes Differently

Diet Affects Men’s and Women’s Intestinal Microbes Differently | Amazing Science |

 The microbes living in the guts of males and females react differently to diet, even when the diets are identical, according to a study by scientists from The University of Texas at Austin and six other institutions published this week in the journal Nature CommunicationsThese results suggest that therapies designed to improve human health and treat diseases through nutrition might need to be tailored for each sex.

The researchers studied the gut microbes in two species of fish and in mice, and also conducted an in-depth analysis of data that other researchers collected on humans. They found that in fish and humans diet affected the microbiota of males and females differently. In some cases, different species of microbes would dominate, while in others, the diversity of bacteria would be higher in one sex than the other.

These results suggest that any therapies designed to improve human health through diet should take into account whether the patient is male or female.

Only in recent years has science begun to completely appreciate the importance of the human microbiome, which consists of all the bacteria that live in and on people’s bodies. There are hundreds or even thousands of species of microbes in the human digestive system alone, each varying in abundance.

Genetics and diet can affect the variety and number of these microbes in the human gut, which can in turn have a profound influence on human health. Obesity, diabetes, and inflammatory bowel disease have all been linked to low diversity of bacteria in the human gut.

One concept for treating such diseases is to manipulate the microbes within a person’s gut through diet. The idea is gaining in popularity because dietary changes would make for a relatively cheap and simple treatment.

Much has to be learned about which species, or combination of microbial species, is best for human health. In order to accomplish this, research has to illuminate how these microbes react to various combinations of diet, genetics and environment. Unfortunately, to date most such studies only examine one factor at a time and do not take into account how these variables interact.

“Our study asks not just how diet influences the microbiome, but it splits the hosts into males and females and asks, do males show the same diet effects as females?” said Daniel Bolnick, professor in The University of Texas at Austin's College of Natural Sciences and lead author of the study.

Eric Chan Wei Chiang's curator insight, August 2, 2014 11:36 PM

Previously, it was assumed that men and women have mostly similar biological functions. This is an interesting paradigm shift indeed. 


This has future implication with our diet and how we treat diseases.

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New tools sift cancer sequences for microsatellite mutations

New tools sift cancer sequences for microsatellite mutations | Amazing Science |

Two new computational tools, MSMuTect and MSMutSig, could help reveal how often mutations in common DNA features called microsatellites appear in, and contribute to, cancer. 


Microsatellites — long stretches of short DNA repeats, such as TCGTCGTCG or ACACAC over and over — are common throughout the genome, both within and outside of genes. Researchers have linked inherited insertion and deletion mutations (also called “indels”) in microsatellites to more than 40 inherited diseases, and clinical labs routinely test for spontaneous or acquired (a.k.a. somatic) indels in certain kinds of cancer. However, technical challenges have stymied efforts to use genome sequencing to systematically catalog cancer-relevant somatic microsatellite indel mutations.


In Nature Biotechnology, a team of researchers led by Yosef Maruvka and Gad Getz of the Broad Institute’s Cancer Genome Computational Analysis group and Massachusetts General Hospital’s Center for Cancer Research and Department of Pathology reveal two computational tools for detecting microsatellite indels in sequencing data from tumor cells. Dubbed MSMuTect and MSMutSig, the tools use statistical approaches to respectively a) identify microsatellite indels, and b) highlight genes harboring more of them than would be expected by chance.


Maruvka, Getz, and their collaborators tested the tools using whole exome sequence data from 6,747 tumors — representing 20 kinds of cancer — and matched normal tissues analyzed by The Cancer Genome Atlas. The two tools revealed more than 1,000 previously undescribed somatic microsatellite indels, as well as potential cancer-promoting indel “hotspots” within seven genes, including three not previously thought of as cancer drivers.


In addition, the team found that with MSMuTect they could correctly classify tumors based on their level of microsatellite instability (that is, a tumor’s predisposition to developing microsatellite indels) — a feature of potential clinical importance.


MSMutTect and MSMutSig add to a large and still-growing sequence analysis toolkitdeveloped by Getz and his colleagues for detecting and describing somatic mutations and other variations in cancer sequence data, including the original MutSig and MuTect(for characterizing point mutations), MutSigCV (which incorporates gene expression and other data to increase MutSig’s accuracy), ABSOLUTE (for measuring a tumor sample’s purity and looking for evidence of abnormal numbers of chromosomes), and GISTIC (for hunting down genomic regions with significant copy number alterations).

Via Integrated DNA Technologies
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UCLA physicists propose new theories of black holes from the very early universe

UCLA physicists propose new theories of black holes from the very early universe | Amazing Science |
The new hypothesis doesn’t rely on the “unlikely coincidences” that underpin other theories explaining primordial black holes.


UCLA physicists have proposed new theories for how the universe's first black holes might have formed and the role they might play in the production of heavy elements such as gold, platinum and uranium. Two papers on their work were published in the journal Physical Review Letters.


A long-standing question in astrophysics is whether the universe's very first black holes came into existence less than a second after the Big Bang or whether they formed only millions of years later during the deaths of the earliest stars.


Alexander Kusenko, a UCLA professor of physics, and Eric Cotner, a UCLA graduate student, developed a compellingly simple new theory suggesting that black holes could have formed very shortly after the Big Bang, long before stars began to shine. Astronomers have previously suggested that these so-called primordial black holes could account for all or some of the universe's mysterious dark matter and that they might have seeded the formation of supermassive black holes that exist at the centers of galaxies. The new theory proposes that primordial black holes might help create many of the heavier elements found in nature.


The researchers began by considering that a uniform field of energy pervaded the universe shortly after the Big Bang. Scientists expect that such fields existed in the distant past. After the universe rapidly expanded, this energy field would have separated into clumps. Gravity would cause these clumps to attract one another and merge together. The UCLA researchers proposed that some small fraction of these growing clumps became dense enough to become black holes.


Their hypothesis is fairly generic, Kusenko said, and it doesn't rely on what he called the "unlikely coincidences" that underpin other theories explaining primordial black holes. The paper suggests that it's possible to search for these primordial black holes using astronomical observations. One method involves measuring the very tiny changes in a star's brightness that result from the gravitational effects of a primordial black hole passing between Earth and that star. Earlier this year, U.S. and Japanese astronomers published a paper on their discovery of one star in a nearby galaxy that brightened and dimmed precisely as if a primordial black hole was passing in front of it.

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Researchers analyze flocking behavior on curved surfaces

Researchers analyze flocking behavior on curved surfaces | Amazing Science |

A murmuration of starlings. The phrase reads like something from literature or the title of an arthouse film. In fact, it is meant to describe the phenomenon that results when hundreds, sometimes thousands, of these birds fly in swooping, intricately coordinated patterns through the sky.

Or in more technical terms, flocking. But birds are not the only creatures that flock. Such behavior also takes place on a microscopic scale, such as when bacteria roam the folds of the gut. Yet bird or bacteria, all flocking has one prerequisite: The form of the entity must be elongated with a "head" and "tail" to align and move with neighbors in an ordered state.


Physicists study flocking to better understand dynamic organization at various scales, often as a way to expand their knowledge of the rapidly developing field of active matter. Case in point is a new analysis by a group of theoretical physicists, including Mark Bowick, deputy director of UC Santa Barbara's Kavli Institute for Theoretical Physics (KITP).


Generalizing the standard model of flocking motion to the curved surface of a sphere rather than the usual linear plane or flat three-dimensional space, Bowick's team found that instead of spreading out uniformly over the whole sphere, arrowlike agents spontaneously order into circular bands centered on the equator.


The team's findings appear in the journal Physical Review X.

Via Mariaschnee
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Half-a-billion-year-old fossils shed light animal evolution on earth

Half-a-billion-year-old fossils shed light animal evolution on earth | Amazing Science |

Scientists have discovered traces of life more than half-a-billion years old that could change the way we think about how all animals evolved on earth.

The international team, including palaeontologist from The University of Manchester, found a new set of trace fossils left by some of the first ever organisms capable of active movement. Trace fossils are the tracks and burrows left by living organisms, not physical remains such as bones or body parts.


The fossils were discovered in sediment in the Corumbá region of western Brazil, near the border with Bolivia. The burrows measure from under 50 to 600 micrometers or microns (μm) in diameter, meaning the creatures that made them were similar in size to a human hair which can range from 40 to 300 microns in width. One micrometer is just one thousandth of a millimeter.


Dr Russell Garwood, from Manchester's School of Earth and Environmental Sciences, said: 'This is an especially exciting find due to the age of the rocks - these fossils are found in rock layers which actually pre-date the oldest fossils of complex animals - at least that is what all current fossil records would suggest.'


The fossils found date back to a geological and evolutionary period known as the Ediacaran-Cambrian transition. This was when the Ediacaran Period, which spanned 94 million years from the end of the Cryogenian Period, 635 million years ago, moved into the Cambrian Period around 541 million years ago. To put that into context, dinosaurs lived between 230 and 65 million years ago in the Mesozoic Era.

Via Mariaschnee
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How Many Hurricanes Can There Be at Once?

How Many Hurricanes Can There Be at Once? | Amazing Science |

This year we saw three, but what's the limit? 


The satellite pictures were a startling sight. As Hurricane Irma barreled toward Florida last week and Hurricane Katia hammered the Mexican coast, Hurricane Jose was waiting in the wings. All at once, three storms gathered strength and grew fiercer.


Seeing a trio of powerful hurricanes simultaneously made a lot of people wonder: Just how many hurricanes can the Atlantic harbor at once?


To try to find an answer, we asked Dr. Anand Gnanadesikan, a climate modeler and professor of Earth and planetary sciences at the Krieger School of Arts and Sciences. According to Gnanadesikan, the number of storms in the Atlantic depends on two main factors. The first is whether or not conditions are favorable to the development of tropical cyclones.


The second thing you need is a spark—"seed" storms that, under the right circumstances, are supercharged into hurricanes. These low-pressure systems sometimes self-organize; other times hurricanes-to-be trace their roots eastward to Africa.


Gnanadesikan explains that there's a limit to how many of these seeds can exist, because if they get too close to one another they can become unstable. They generally form a few thousand kilometers apart, which means there's limited space. Gnanadesikan says: "So a question one could ask is, 'How many seeds might one find in the Atlantic and how likely is it that they will all grow?'"


Using NOAA's HURDAT2 database, which contains data from as far back as 1851, Gnanadesikan found that any time one tropical cyclone is present in the Atlantic, there's historically about a 20 percent chance that a second seed will level up into a cyclone. The odds of a third seed ascending are roughly the same—20 percent of the those two-storms situations. This diminishing trend probably leads to a three-cyclone situation in about four percent of records, a number Gnanadesikan says was higher than expected, but also includes many cyclones which never made landfall.


By the time you get to four or more cyclones at one, that level is found in only about 340 records—less than one percent. At about four simultaneous storms, Gnanadesikan says, "you might start running out of seeds."

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Swarm of Origami Robots Can Self Assemble Out of a Single Sheet

Swarm of Origami Robots Can Self Assemble Out of a Single Sheet | Amazing Science |

One of the biggest challenges with swarms of robots is manufacturing and deploying the swarm itself. Even if the robots are relatively small and relatively simple, you’re still dealing with a whole bunch of them, and every step in building the robots or letting them loose is multiplied over the entire number of bots in the swarm. If you’ve got more than a few robots to handle, it starts to get all kinds of tedious.


The dream for swarm robotics is to be able to do away with all of that, and just push a button and have your swarm somehow magically appear. We’re not there yet, but we’re getting close: At IROS this month, researchers from the Wyss Institute for Biologically Inspired Engineering at Harvard presented a paper demonstrating an autonomous collective robotic swarm that can be manufactured in a single flat composite sheet. On command, they’ll rip themselves apart from each other, fold themselves up into origami structures, and head off on a mission en masse.


The process works like this: There are four robots in this sheet, and they’re pretty darn near two dimensional. Want more robots? No problem, just make the sheet bigger. The sheet itself consists of six layers, which are all automatically laser machined: A pre-stretched polystyrene, or PSPS, layer (a kind of shape-memory polymer) in the center, sandwiched between layers of copper circuits etched into polyimide sheets, with paper substrates for support. The PSPS is the magical stuff: When heated above 100° C (which can be done by running a 2.5-ampere current through the copper circuitry), it shrinks, which is what powers the robots’ self-folding behaviors.


Otherwise, each robot consists of some discrete electrical components that have to be placed by hand, but according to co-author Michael Tolley, “we foresee straightforward ways to automate these steps.” Self-folding robots that use shape-memory polymers have been done before, but the challenge with them is to accurately control the folding. To address that issue, the Harvard researchers came up with a clever feedback-controlled assembly technique by using phototransistors and infrared LEDs to precisely measure the fold angles, “greatly improving the repeatability of self-folding,” says Tolley, who now leads UC San Diego’s Bioinspired Robotics and Design Lab.


The final thing that sets these self-folding bots apart is their ability to go from a single continuous sheet to a swarm of discrete robots. Self-folding joints that are designed to prevent folding causes the PSPS to instead rip itself apart, allowing each robot to split off by itself, where its vibration motors can help it buzz along flat surfaces seeking sources of light.

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A single-molecule room-temperature transistor made from 14 atoms

A single-molecule room-temperature transistor made from 14 atoms | Amazing Science |

Columbia Engineering researchers have taken a key step toward atomically precise, reproducible transistors made from single molecules and operating at room temperature — a major goal in the field of molecular electronics.


The team created a two-terminal transistor with a diameter of about 0.5 nanometers and core consisting of just 14 atoms. The device can reliably switch from insulator to conductor when charge is added or removed, one electron at a time (known as “current blockade”).


The research was published in the journal Nature Nanotechnology. “With these molecular clusters, we have complete control over their structure with atomic precision and can change the elemental composition and structure in a controllable manner to elicit certain electrical response,” says Latha Venkataraman, leader of the Columbia research team.


The researchers plan to design improved molecular cluster systems with better electrical performance (such as higher on/off current ratio and different accessible states) and increase the number of atoms in the cluster core, while maintaining the atomic precision and uniformity of the compound.


Other studies have created quantum dots to produce similar effects, but the dots are much larger and not uniform in size, and the results have not been reproducible. The ultimate size reduction would be single-atom transistors, but they require ultra-cold temperatures (minus 196 degrees Celsius in this case, for example).

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Are we being watched? Many alien worlds could spot the Earth

Are we being watched? Many alien worlds could spot the Earth | Amazing Science |

A group of scientists from Queen's University Belfast and the Max Planck Institute for solar system Research in Germany have turned exoplanet-hunting on its head, in a study that instead looks at how an alien observer might be able to detect Earth using our own methods. They find that at least nine exoplanets are ideally placed to observe transits of Earth, in a new work published in the journal Monthly Notices of the Royal Astronomical Society.



Thanks to facilities and missions such as SuperWASP and Kepler, we have now discovered thousands of planets orbiting stars other than our sun, worlds known as 'exoplanets'. The vast majority of these are found when the planets cross in front of their host stars in what are known as 'transits', which allow astronomers to see light from the host star dim slightly at regular intervals every time the planet passes between us and the distant star.


In the new study, the authors reverse this concept and ask, "How would an alien observer see the solar system?" They identified parts of the distant sky from where various planets in our solar system could be seen to pass in front of the sun – so-called 'transit zones'—concluding that the terrestrial planets (Mercury, Venus, Earth, and Mars) are actually much more likely to be spotted than the more distant 'Jovian' planets (Jupiter, Saturn, Uranus, and Neptune), despite their much larger size.


"Larger planets would naturally block out more light as they pass in front of their star", commented lead author Robert Wells, a PhD student at Queen's University Belfast. "However the more important factor is actually how close the planet is to its parent star – since the terrestrial planets are much closer to the sun than the gas giants, they'll be more likely to be seen in transit."

Nevermore Sithole's curator insight, September 11, 8:11 AM
Are we being watched? Many alien worlds could spot the Earth
Donald Schwartz's curator insight, September 12, 11:39 AM

Here's looking right back at you kid.

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High-speed quantum memory for photons

High-speed quantum memory for photons | Amazing Science |
Physicists have developed a memory that can store photons. These quantum particles travel at the speed of light and are thus suitable for high-speed data transfer.


The researchers were able to store them in an atomic vapor and read them out again later without altering their quantum mechanical properties too much. This memory technology is simple and fast and it could find application in a future quantum Internet.The journal Physical Review Letters has published the results ("Simple Atomic Quantum Memory Suitable for Semiconductor Quantum Dot Single Photons").

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New AI technique creates 3-D shapes from 2-D images

New AI technique creates 3-D shapes from 2-D images | Amazing Science |
A new technique that uses the artificial intelligence methods of machine learning and deep learning is able to create 3-D shapes from 2-D images, such as photographs, and is even able to create new, never-before-seen shapes.


Karthik Ramani, Purdue's Donald W. Feddersen Professor of Mechanical Engineering, says that the "magical" capability of AI deep learning is that it is able to learn abstractly. "If you show it hundreds of thousands of shapes of something such as a car, if you then show it a 2-D image of a car, it can reconstruct that model in 3-D," he says. "It can even take two 2-D images and create a 3-D shape between the two, which we call 'hallucination.'"


When fully developed, this method, called SurfNet, could have significant applications in the fields of 3-D searches on the Internet, as well as helping robotics and autonomous vehicles better understand their surroundings. Perhaps most exciting, however, is that the technique could be used to create 3-D content for virtual reality and augmented reality by simply using standard 2-D photos.


"You can imagine a movie camera that is taking pictures in 2-D, but in the virtual reality world everything is appearing magically in 3-D," Ramani says. "Inch-by-inch we are going there, and in the next five years something like this is going to happen.

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TRAPPIST-1’s Outer Planets May Harbor Water, New Study Finds

TRAPPIST-1’s Outer Planets May Harbor Water, New Study Finds | Amazing Science |

TRAPPIST-1 is an ultracool dwarf star in the constellation Aquarius, 38.8 light-years away. It is barely larger than Jupiter and has just 8% of our Sun’s mass. It is rapidly spinning and generates energetic flares of ultraviolet (UV) radiation. This dwarf star is host to seven transiting planets, named TRAPPIST-1b, c, d, e, f, g and h. All these planets are similar in size to Earth and Venus, or slightly smaller, and have very short orbital periods.


They are likely all tidally locked, meaning the same face of the planet is always pointed at the star, as the same side of the Moon is always pointed at Earth. This creates a perpetual night side and perpetual day side on each TRAPPIST-1 planet.


TRAPPIST-1e, f and g lay in the star’s habitable zone, meaning they may harbor suitable conditions for life. Following up on the discovery, Dr. Vincent Bourrier of the Geneva Observatory and colleagues used Hubble’s Space Telescope Imaging Spectrograph to study the amount of UV radiation received by TRAPPIST-1 planets.


“UV radiation is an important factor in the atmospheric evolution of planets. As in Earth’s atmosphere, where UV sunlight breaks molecules apart, UV starlight can break water vapor in the atmospheres of exoplanets into hydrogen and oxygen,” Dr. Bourrier said. “While lower-energy UV radiation breaks up water molecules — a process called photodissociation — UV rays with more energy (XUV radiation) and X-rays heat the upper atmosphere of a planet, which allows the products of photodissociation, hydrogen and oxygen, to escape.”


“As it is very light, hydrogen gas can escape the exoplanets’ atmospheres and be detected around the exoplanets with Hubble, acting as a possible indicator of atmospheric water vapor,” Dr. Bourrier explains.


The observed amount of UV radiation emitted by the TRAPPIST-1 star indeed suggests that the planets could have lost gigantic amounts of water over the course of their history. This is especially true for the innermost two planets of the system, TRAPPIST-1b and TRAPPIST-1c, which receive the largest amount of UV energy. “Our results indicate that atmospheric escape may play an important role in the evolution of these planets,” said co-author Dr. Julien de Wit, of MIT.

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Large-scale Study of Genetic Data Shows Humans Still Evolving

Large-scale Study of Genetic Data Shows Humans Still Evolving | Amazing Science |

In a study analyzing the genomes of 210,000 people in the United States and Britain, Columbia researchers find that the genetic variants linked to Alzheimer’s disease and heavy smoking are less frequent in people with longer lifespans, suggesting that natural selection is weeding out these unfavorable variants in both populations.


Researchers further find that sets of genetic mutations that predispose people to early puberty and childbearing, heart disease, high cholesterol, obesity, and asthma, also appear less often in people who lived longer and whose genes are therefore more likely to be passed down and spread through the population. The results are published in the Sept. 5 issue of PLOS Biology.


“It’s a subtle signal, but we find genetic evidence that natural selection is happening in modern human populations,” said study coauthor Joseph Pickrell, an evolutionary geneticist at Columbia and New York Genome Center.


New favorable traits evolve when genetic mutations arise that offer a survival edge. As the survivors of each generation pass on those beneficial mutations, the mutations and their adaptive traits become more common in the general population. Though it may take millions of years for complex traits to evolve, say allowing humans to walk on two legs, evolution itself happens with each generation as adaptive mutations become more frequent in the population.


The genomic revolution has allowed biologists to see the natural selection process in action by making the genetic blueprint of hundreds of thousands of people available for comparison. By tracking the relative rise and fall of specific mutations across generations of people, researchers can infer which traits are spreading or dwindling.


The researchers analyzed the genomes of 60,000 people of European ancestry genotyped by Kaiser Permanente in California, and 150,000 people in Britain genotyped through the U.K. Biobank. To compensate for the relative lack of old people in the Biobank, the researchers used the participants’ parents age at death as a proxy as they looked for the influence of specific mutations on survival. 

Via Integrated DNA Technologies
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Large-scale Study of Genetic Data Shows Humans Still Evolving
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Helically twisted photonic crystal fibers show surprising features

Helically twisted photonic crystal fibers show surprising features | Amazing Science |

Photonic crystal fibers (PCF) are strands of glass, not much thicker than a human hair, with a lattice of hollow channels running along the fiber. If they are continuously twisted in their production, they resemble a multi-helix. Twisted PCFs show some amazing features, from circular birefringence to conservation of the angular momentum. The biggest surprise, however, is the robust light guidance itself, with no visible fiber core. The basis for this are forces which, like gravitation, are based on the curvature of space.

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Accretion-powered pulsar reveals unique timing glitch

Accretion-powered pulsar reveals unique timing glitch | Amazing Science |

The discovery of the largest timing irregularity yet observed in a pulsar is the first confirmation that pulsars in binary systems exhibit the strange phenomenon known as a ‘glitch’. The study is published in the journal Monthly Notices of the Royal Astronomical Society.


Pulsars are one possible result of the final stages of evolution of massive stars. Such stars end their lives in hugesupernova explosions, ejecting their stellar materials outwards into space and leaving behind an extremely dense and compact object; this could either be a white dwarf, a neutron star or a black hole.


If a neutron star is left, it may have a very strong magnetic field and rotate extremely quickly, emitting a beam of light that can be observed when the beam points towards Earth, in much the same way as a lighthouse beam sweeping past an observer. To the observer on Earth, it looks as though the star is emitting pulses of light, hence the name ‘pulsar’.


Now a group of scientists from the Middle East Technical University and Başkent University in Turkey have discovered a sudden change in the rotation speed of the peculiar pulsar SXP 1062. These jumps in frequency, known as ‘glitches’, are commonly seen in isolated pulsars, but have so far never been observed in binary pulsars (pulsars orbiting with a companion white dwarf or neutron star) such as SXP 1062.


SXP 1062 is located in the Small Magellanic Cloud, a satellite galaxy of our own Milky Way galaxy, and one of our nearest intergalactic neighbours at 200,000 light years away. Lead author of the study, Mr M. Miraç Serim, a senior PhD student working under the supervision of Prof Altan Baykal, said, “This pulsar is particularly interesting, since as well as orbiting its partner star as part of a binary pair, it is also still surrounded by the remnants of the supernova explosion which created it.”


The pulsar is thought to pull in the leftover material from the supernova explosion, feeding on it in a process known as accretion. The team believe that the size of the glitch is due to the gravitational influence of its companion star and this accretion of the surrounding remnant material, which together exert large forces on the crust of the neutron star. When these forces are no longer sustainable, a rapid change in internal structure transfers momentum to the crust, changing the rotation of the pulsar very suddenly and producing a glitch.


“The fractional frequency jump observed during this glitch is the largest, and is unique to this particular pulsar”, commented Dr Şeyda Şahiner, a co-author of the study. “The size of the glitch indicates that the interiors of neutron stars in binary systems may be quite different to the interiors of isolated neutron stars.”


This work was initially presented in 2017 at the European Week of Astronomy and Space Science, which will be held next year in Liverpool jointly with the UK National Astronomy Meeting. The work will be followed up with NASA’s Neutron Star Interior Composition Explorer (NICER) mission, launched in June this year – the team hope that the finding may lead to a better understanding of the interior of the neutron stars, putting new constraints on the neutron star equation of state.

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Eat Fat, Live Longer? Mouse study says "yes"

Eat Fat, Live Longer? Mouse study says "yes" | Amazing Science |

As more people live into their 80s and 90s, researchers have delved into the issues of health and quality of life during aging. A recent mouse study at the UC Davis School of Veterinary Medicine sheds light on those questions by demonstrating that a high-fat, or ketogenic, diet not only increases longevity, but improves physical strength.


“The results surprised me a little,” said nutritionist Jon Ramsey, senior author of the paper that appears in the September issue of Cell Metabolism. “We expected some differences, but I was impressed by the magnitude we observed — a 13 percent increase in median life span for the mice on a high-fat versus high-carb diet. In humans, that would be seven to 10 years. But equally important, those mice retained quality of health in later life.”


Ramsey has spent the past 20 years looking at the mechanics that lead to aging, a contributing factor to most major diseases that impact rodents and humans alike. While calorie restriction has been shown in several studies to slow aging in many animals, Ramsey was interested in how a high-fat diet may impact the aging process.


Ketogenic diets have gained popularity for a variety of health benefit claims, but scientists are still teasing out what happens during ketosis, when carbohydrate intake is so low that the body shifts from using glucose as the main fuel source to fat burning and producing ketones for energy.

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When electrons ride a wave

When electrons ride a wave | Amazing Science |

Conventional electron accelerators have become an indispensable tool in modern research. The extremely bright radiation generated by synchrotrons, or free electron lasers, provides us with unique insights into matter at the atomic level. But even the smallest versions of these super microscopes are the size of a soccer field.


Laser plasma acceleration could offer an alternative: with a much smaller footprint and much higher peak currents it could be the basis for the next generation of compact light sources. So far, the challenge with laser accelerators has been to create a reliable and stable electron beam, which is the prerequisite for possible applications. Physicists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) have now developed a method to increase both beam stability and quality.


The basic principle of laser acceleration seems quite simple: A bundled, ultra-strong laser beam hits a trace of gas, which instantly creates plasma - an ionized state of matter or, in other words, a whirling mix of charged particles. The power of the light pulse pushes electrons away from their parent ions, creating a sort of bubble-like structure with a strong electric field in the plasma. This field, which the laser pulse drags behind itself like a stern wave, traps the electrons, accelerating them to nearly the speed of light. "These speedy particles allow us to generate x-rays," Dr. Arie Irman from the HZDR Institute of Radiation Physics explains the purpose of the procedure. "For instance, when we make these electron bundles collide with another laser beam, the impact generates bright, ultra-short x-ray flashes - an immensely valuable research tool for examining extreme states of matter."


The strength of the secondary radiation greatly depends on the particles' electrical current. The current, in turn, is mostly determined by the number of electrons fed into the process. Laser-powered acceleration therefore holds great potential, because it reaches significantly higher peak currents in comparison with the conventional method. However, as physicist Jurjen Pieter Couperus points out, the so-called beam loading effect kicks in: "These higher currents create an electric self-field strong enough to superimpose and disturb the laser-driven wave, distorting thereby the beam. The bundle is stretched out and not accelerated properly. The electrons therefore have different energies and quality levels." But in order to use them as a tool for other experiments, each beam must have the same parameters.


"The electrons have to be in the right place at the right time," summarizes Couperus, who is a Ph.D. candidate in Irman's team.

Together with other colleagues at the HZDR, the two researchers were the first to demonstrate how the beam loading effect can be exploited for improved beam quality. They add a bit of nitrogen to the helium at which the laser beam is usually directed. "We can control the number of electrons we feed into the process by changing the concentration of the nitrogen," Irman explains. "In our experiments, we found out that conditions are ideal at a charge of about 300 picocoulomb. Any deviation from it - if we add more or fewer electrons to the wave - results in a broader spread of energy, which impairs beam quality."

Via Mariaschnee
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Explosive birth of stars swells galactic cores

Explosive birth of stars swells galactic cores | Amazing Science |

Astronomers found that active star formation upswells galaxies, like yeast helps bread rise. Using three powerful telescopes on the ground and in orbit, they observed galaxies from 11 billion years ago and found explosive formation of stars in the cores of galaxies. This suggests that galaxies can change their own shape without interaction with other galaxies.


"Massive elliptical galaxies are believed to be formed from collisions of disk galaxies," said Ken-ichi Tadaki, the lead author of two research papers and a postdoctoral researcher at the National Astronomical Observatory of Japan (NAOJ). "But, it is uncertain whether all the elliptical galaxies have experienced galaxy collision. There may be an alternative path."


Aiming to understand galactic metamorphosis, the international team explored distant galaxies 11 billion light-years away. Because it takes time for the light from distant objects to reach us, by observing galaxies 11 billion light-years away, the team can see what the Universe looked like 11 billion years ago, 3 billion years after the Big Bang. This corresponds the peak epoch of galaxy formation; the foundations of most galaxies were formed in this epoch.


Receiving faint light which has travelled 11 billion years is tough work. The team harnessed the power of three telescopes to anatomize the ancient galaxies. First, they used NAOJ's 8.2-m Subaru Telescope in Hawai`i and picked out 25 galaxies in this epoch. Then they targeted the galaxies for observations with NASA/ESA's Hubble Space Telescope (HST) and the Atacama Large Millimeter/submillimeter Array (ALMA). The astronomers used HST to capture the light from stars which tells us the "current" (as of when the light was emitted, 11 billion years ago) shape of the galaxies, while ALMA observed submillimeter waves from cold clouds of gas and dust, where new stars are being formed. By combining the two, we know the shapes of the galaxies 11 billion years ago and how they are evolving.


Thanks to their high resolution, HST and ALMA could illustrate the metamorphosis of the galaxies. With HST images the team found that a disk component dominates the galaxies. Meanwhile, the ALMA images show that there is a massive reservoir of gas and dust, the material of stars, so that stars are forming very actively. The star formation activity is so high that huge numbers of stars will be formed at the centers of the galaxies. This leads the astronomers to think that ultimately the galaxies will be dominated by the stellar bulge and become elliptical or lenticular galaxies.

Via Mariaschnee
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In one day, an average hurricane releases as much energy as half a million atomic bombs

In one day, an average hurricane releases as much energy as half a million atomic bombs | Amazing Science |
We know how damaging and costly, in many ways, such natural phenomena can be — but the devastation is not surprising, once you know how much energy is involved, says astrophysicist Marcelo Gleiser.


America seems to be a magnet for devastating hurricanes these days. This year, Harvey came out strong with its horrific toll on parts of Texas and Louisiana. Now Irma, downgraded slightly Friday morning to a Category 4 storm from its most recent days as a Category 5, has left destruction in its wake as it plows through the Caribbean and Cuba — and is on path to hit Florida Sunday morning.


It's too early to know if this will be a particularly bad year, as the average number of major hurricanes in the U.S. per decade is roughly six. But averages, important as they are, mean little to those who have to brace for impact. We know how damaging such natural phenomenon can be — and how costly, at many levels, from emotional loss to rebuilding costs in the billions of dollars. The devastation is not surprising, once you know how much energy is involved.


Consider this: In one day, an average hurricane releases as much energy as half a million atomic bombs, a force to be reckoned with.


When the sun heats an ocean to more than 82 degrees, moist hot air rises up meeting cooler air — creating thunderstorms. Upper-level winds and surface winds come together, forming a circular pattern called a tropical depression. Why circular? See below.


Then, when the winds reach 74 miles per hour, a hurricane forms, sometimes as wide as 500 miles in diameter, nearly the size of Texas, reaching heights of nine miles. This short National Geographic info-video is a good introduction to hurricanes.

Remarkably, hurricanes spin counter-clockwise in the Northern Hemisphere and clockwise in the Southern hemisphere. This differential spinning is due to Earth's rotation. If the Earth didn't rotate, winds of up to 300 miles per hour would howl from the poles to the Equator and back. But Earth's spin, and because the equatorial regions spin a bit faster than the regions at higher and lower latitudes, affects the air currents due to what is known as the Coriolis effect. In the first half of the 19th century, French engineer and mathematician Gustave Gaspard Coriolis proposed it as an explanation as to how the motion of objects is affected when they are on a rotating basis or reference frame, like the spinning Earth or a merry-go-round.


Think of the Earth as a big ball rotating from West to East. So, if you are looking at it from the top, it will rotate counter-clockwise. Air currents near the equator get pushed a bit faster than those closer to the poles, with those above the Equator getting pushed to the right and those below it to the left. It is this pushing that causes hurricanes in the North to rotate counter-clockwise and those in the South, clockwise. This also explains why hurricanes don't cross the equator, as the Coriolis effect there is too weak to get the air spinning fast enough.

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DNA Origami

DNA Origami | Amazing Science |

Since DNA forms basepairs in a predictable way, by cleverly designing the sequences of several strands of DNA you can coax them to self-assemble into a particular shape.


Until recently, DNA origami has been constrained to two dimensional shapes like smiley faces, stars, and other things. These are entertaining, but this technology has potential applications besides aesthetic. Maybe one day we can build containers for drugs using DNA origami that carry medicine to particular cells, say chemotherapy drugs to cancer cells while sparing healthy cells from the same fate. Maybe one can take advantage of the stability of DNA by using it to build scaffolds on which tissues or whole organs can grow. These two applications clearly require taking DNA origami into three dimensions, which is just what Dongran Han and his colleagues did. In their designs they used one long piece of ssDNA, called the scaffold, and many small pieces of ssDNA, called staples. By choosing staples carefully, they were able to contort the scaffold into a desired shape. They began by building simple concentric circles in two dimensions with the scaffold weaving in and out between the rings. They then varied the parameters of their design to build three dimensional shapes with circular cross sections. They managed to build hemispheres, spheres, ellipsoids (stretched spheres), and flasks. They called their DNA flask the "nanoflask" in reference to its nanoscale size. The pictures of these shapes shown below are transmission electron micrographs in black and white and atomic force micrographs in yellow and red. Electron microscopes use a beam of electrons instead of light to focus on objects much smaller than the wavelength of visible light. Atomic force microscopes feel their way through a sample using a tiny needle tipped with a single atom.

Lucy Pérez's curator insight, September 11, 4:28 PM

DNA interesting dates!

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Scientists discover the oldest human fossil in Morocco

Scientists discover the oldest human fossil in Morocco | Amazing Science |
Scientists discover the oldest homo sapiens fossils at Jebel Irhoud, Morocco


An international research team led by Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology (Leipzig, Germany) and Abdelouahed Ben-Ncer of the National Institute for Archaeology and Heritage (INSAP, Rabat, Morocco) uncovered fossil bones of Homo sapiens along with stone tools and animal bones at Jebel Irhoud, Morocco. The finds are dated to about 300 thousand years ago and represent the oldest securely dated fossil evidence of our own species. This date is 100 thousand years earlier than the previous oldest Homo sapiens fossils. The discoveries reported in two papers in the June 8th issue of the journal Nature by Hublin et al. and by Richter et al. reveal a complex evolutionary history of mankind that likely involved the entire African continent.


Both genetic data of present day humans and fossil remains point to an African origin of our own species, Homo sapiens. Previously, the oldest securely datedHomo sapiens fossils were known from the site of Omo Kibish in Ethiopia, dated to 195 thousand years ago. At Herto, also in Ethiopia, a Homo sapiens fossil is dated to 160 thousand years ago. Until now, most researchers believed that all humans living today descended from a population that lived in East Africa around 200 thousand years ago. "We used to think that there was a cradle of mankind 200 thousand years ago in east Africa, but our new data reveal that Homo sapiensspread across the entire African continent around 300 thousand years ago. Long before the out-of-Africa dispersal of Homo sapiens, there was dispersal within Africa," says palaeoanthropologist Jean-Jacques Hublin.

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Study of Uranus suggests some of its moons are on a collision course

Study of Uranus suggests some of its moons are on a collision course | Amazing Science |

A trio of researchers, two with the University of Idaho, the other with Wellesley College, has found evidence suggesting that two pairs of Uranus's moons are on a collision course.


Uranus is the seventh planet from the sun and the third largest. Prior research has suggested that it is, like Neptune, an ice giant (as compared to gas giants). It has also been found to have the chilliest atmosphere among all the planets in the solar system. And it has both a ring system and multiple satellites—27 in all. The satellites orbiting the planet are believed to be very low mass compared to the moons of the other planets, and some of them, according to this latest research, are on a collision course that will shatter them into small bits.


The researchers report that they were studying the planet's rings, which are collectively called Eta, and discovered that they had an oddly shaped orbit—not round or even circular. Instead, they describe it as sort of triangular. More study showed that the odd orbit of the rings was due to gravitational pull from Cressida—one of the planet's moons. The gravitational impact is exaggerated, they note, due to the moon keeping pace with the orbit of the planet. The particles in the ring, on the other hand, move faster than the moon. This results in the moon tugging on the ring at as it passes by, causing the odd orbital shape. The tug exerted by the moon on the rings allowed the team to deduce its mass. They found that it is around 1/300,000th that of our own moon. Also, it has only 86 percent of the density of water, which indicates it is porous.


In studying the orbits of the moons, the researchers found that Cressida is on a path that will cause it to collide with another moon called Desdemona, which currently moves in an orbit just 900 kilometers from Cressida's. The gravity of Cressida is slowly pulling them closer together and will cause them to crash into one another in approximately 1 million years. They also found the same to be true for Cupid and Belinda, which will collide sometime later.\

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Drawing electricity from the bloodstream with a nanogenerator

Drawing electricity from the bloodstream with a nanogenerator | Amazing Science |

Men build dams and huge turbines to turn the energy of waterfalls and tides into electricity. To produce hydropower on a much smaller scale, Chinese scientists have now developed a lightweight power generator based on carbon nanotube fibers suitable to convert even the energy of flowing blood in blood vessels into electricity. They describe their innovation in the journal Angewandte Chemie ("A One-Dimensional Fluidic Nanogenerator with a High Power Conversion Efficiency").


For thousands of years, people have used the energy of flowing or falling water for their purposes, first to power mechanical engines such as watermills, then to generate electricity by exploiting height differences in the landscape or sea tides.Using naturally flowing water as a sustainable power source has the advantage that there are (almost) no dependencies on weather or daylight. Even flexible, minute power generators that make use of the flow of biological fluids are conceivable.How such a system could work is explained by a research team from Fudan University in Shanghai, China.


Huisheng Peng and his co-workers have developed a fiber with a thickness of less than a millimeter that generates electrical power when surrounded by flowing saline solution—in a thin tube or even in a blood vessel.The construction principle of the fiber is quite simple. An ordered array of carbon nanotubes was continuously wrapped around a polymeric core. Carbon nanotubes are well known to be electroactive and mechanically stable; they can be spun and aligned in sheets. In the as-prepared electroactive threads, the carbon nanotube sheets coated the fiber core with a thickness of less than half a micron. For power generation, the thread or "fiber-shaped fluidic nanogenerator" (FFNG), as the authors call it, was connected to electrodes and immersed into flowing water or simply repeatedly dipped into a saline solution.


"The electricity was derived from the relative movement between the FFNG and the solution," the scientists explained. According to the theory, an electrical double layer is created around the fiber, and then the flowing solution distorts the symmetrical charge distribution, generating an electricity gradient along the long axis.The power output efficiency of this system was high. Compared with other types of miniature energy-harvesting devices, the FFNG was reported to show a superior power conversion efficiency of more than 20%. Other advantages are elasticity, tunability, lightweight, and one-dimensionality, thus offering prospects of exciting technological applications. The FFNG can be made stretchable just by spinning the sheets around an elastic fiber substrate. If woven into fabrics, wearable electronics become thus a very interesting option for FFNG application.

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Bosch launches air quality monitoring system for smart cities, based on Intel IoT architecture

Bosch launches air quality monitoring system for smart cities, based on Intel IoT architecture | Amazing Science |

Bosch has launched a system designed to monitor air quality in smart cities so officials can react quickly to improve the quality of life. The system, the Bosch Air Quality Micro Climate Monitoring System (MCMS), is based on Intel technology, sensors and software to measure air quality.


MCMS offers microclimate data measurements for EPA pollutants, including particulate matter, carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, sulfur dioxide and ozone. MCMS also tracks temperature, humidity, light, sound and pressure. With the data compiled, MCMS can analyze conditions and then adjust traffic flow and change emissions at factories and industrial settings. Construction sites can also provide early warning signals based on conditions.


MCMS, available now, is compact and built for rugged conditions. It includes remote monitoring via wired and wireless interfaces. Sensors can also be calibrated over the air. In addition, MCMS is based on Intel's IoT reference architecture, Wind River Helix Device Cloud, for edge devices and security tools.

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Glowing Nanoparticle Ink Could Lead to Easy DIY Holograms

Glowing Nanoparticle Ink Could Lead to Easy DIY Holograms | Amazing Science |
Want to make phosphorescent ink? Dope it with some europium.


A team of scientists have demonstrated for the first time an inkjet fabrication of highly efficient luminescent structures based on Eu-doped ZrO2 nanocrystals (3.4 ± 0.3 nm), with a refractive index close to the one of the bulk materials. The nanoparticles were synthesized using a non-hydrolytic method in benzyl alcohol where the particles were post treated using acetic acid, leading to the formation of a stable colloid. It was shown that the non-polar methyl group of the acetic acid is responsible for its penetration through the hydrophobic layer all the way through to the surface of the ZrO2, leading to the cleavage of the Zr–OCH2C6H5 bond and the formation of surface acetate species and a concomitant decomposition of the zirconia superlattice.


They show us a new and efficient universal ink production through a multi-step process – starting from solvothermal synthesis, dispersion of nanocrystals in water, and adaptation of the rheological parameters of the resulting sols. Eventually, they were able to obtain inks that could be used for the production of optical coatings, monolayer luminescent-protected holography and anti-counterfeiting printing. These structures, obtained at room temperature through inkjet printing, present dense xerogel structures with high optical transparency, a high refractive index and more efficient luminescence compared with the non-homogeneous structures produced as a mixture of rare-earth elements and nanocrystals.

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#Scientists hatch bold plan to save planet from #supervolcano eruption #Yellowstone

#Scientists hatch bold plan to save planet from #supervolcano eruption #Yellowstone | Amazing Science |
NASA researchers say siphoning heat from the Yellowstone Caldera could lower the risk of a deadly eruption while generating electricity.


Humans have witnessed many cataclysmic volcanic eruptions, from the one that destroyed Pompeii in 79 A.D. to the extraordinary Krakatoa eruption of 1883. But around the world right now there are about 20 so-called “supervolcanoes” that could outdo them all.

One of these monster volcanoes lurks beneath Yellowstone National Park. The Yellowstone Caldera is an enormous craterlike depression measuring 30 miles by 45 miles and filled with molten material (magma). If it were to blast its innards out in a super-eruption, it’s no exaggeration to say that the human race could be imperiled.


But scientists at NASA have sketched the rough outlines of a plan that they say would not only spare us from a deadly super-eruption but also turn the Yellowstone supervolcano into a source of electric power. In a write-up of the plan first shared with the BBC, the team argues that we could siphon heat from the caldera until it becomes too cool to erupt — and convert the geothermal energy into electricity.

Via CineversityTV
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