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A patient was diagnosed with Ebola in the United States for the first time, CNBC reported, citing the U.S. Centers for Disease Control and Prevention (CDC). Until Tuesday, Ebola patients had only been treated in the U.S. after being diagnosed elsewhere. The AP confirmed the news.
According to WFAA.com, the patient was being treated at a Dallas hospital. Texas Health Presbyterian Hospital of Dallas announced on Monday that one its patients was being tested for Ebola. The patient was kept in isolation and CDC officials headed to Dallas to meet with doctors there. Texas health officials believe that the chances of an outbreak in the Dallas area are very low.
he CDC gave more details about the case in a Tuesday press conference.
Dr. Thomas Frieden, Director of the CDC, reported that the infected patient was traveling from Liberia and left on September 19th, arrived in the U.S. on September 20th, but had no symptoms of the disease during that timeframe. On September 24th, the patient developed symptoms, and then sought care on September 26th. On September 28th, the patient was admitted to the hospital in Dallas. Frieden stated that he had "no doubt that we'll stop this in its tracks in the U.S."
Friedan didn’t disclose much information about the patient beyond the fact that he is visiting family in the U.S. Doctors didn't reveal his nationality -- or whether he resides in the U.S. or is a tourist. Officials did confirm that he was critically ill and that the hospital was discussing experimental therapies with the patient’s family and drug providers.
Retrotransposons are thought to be remnants of ancient viruses that infected early animals and inserted their genes into the genome long before humans evolved. Now they can only replicate themselves within the genome. Depending on where a new copy gets inserted into the genome, a jumping event can disrupt normal genes and cause disease. Often the effect is neutral, simply adding to the overall size of the genome. Very rarely the effect might be advantageous, because the added DNA can itself be a source of new regulatory elements that enhance gene expression. But the high probability of deleterious effects means natural selection favors the evolution of mechanisms to prevent jumping events.
Their findings, published September 28 in Nature, show that over evolutionary time, primate genomes have undergone repeated episodes in which mutations in jumping genes allowed them to escape repression, which drove the evolution of new repressor genes, and so on. Furthermore, their findings suggest that repressor genes that originally evolved to shut down jumping genes have since come to play other regulatory roles in the genome.
"We have basically the same 20,000 protein-coding genes as a frog, yet our genome is much more complicated, with more layers of gene regulation. This study helps explain how that came about," said Sofie Salama, a research associate at the UC Santa Cruz Genomics Institute who led the study.
Researchers at the Department of Energy’s Oak Ridge National Laboratory are the first team to sequence the entire genome of the Clostridium autoethanogenum bacterium, which is used to sustainably produce fuel and chemicals from a range of raw materials, including gases derived from biomass and industrial wastes.
Reporting in the journal Nature Physics, physicists from Imperial College London and the Friedrich-Schiller-Universität Jena, in Germany, used semiconductor nanowires made of zinc oxide and placed them on a silver surface to create ultra-fast lasers.
By using silver rather than a conventional glass surface, the scientists were able to shrink their nanowire lasers down to just 120 nanometres in diameter - around a thousandth the diameter of human hair.
The physicists were able to shrink the laser by using surface plasmons, which are wave-like motions of excited electrons found at the surface of metals. When light binds to these oscillations it can be focused much more tightly than usual.
By using surface plasmons they were able to squeeze the light into a much smaller space inside the laser, which allowed the light to interact much more strongly with the zinc oxide.
This stronger interaction accelerated the rate at which the laser could be turned on and off to ten times that of a nanowire laser using a glass surface. These are the fastest lasers recorded to date, in terms of the speed at which they can turn on and off.
Senior author Dr Rupert Oulton from the Department of Physics at Imperial College London said: “This work is so exciting because we are engineering the interaction of light and matter to drive light generation in materials much faster than it occurs naturally. When we first started working on this, I would have been happy to speed up switching speeds to a picosecond, which is one trillionth of a second. But we’ve managed to go even faster, to the point where the properties of the material itself set a speed limit.”
PhD student Robert Röder, from Friedrich-Schiller Universität Jenasaid: “This is not only ‘world record’ regarding the switching speed. Most likely we also achieved the maximum possible speed at which such a semiconductor laser can be operated.”
More than a quarter of Vietnam’s residents live in areas likely to be subject to regular floods by the end of the century. Four percent of China’s residents — 50 million people — live in the same kind of areas. Across the globe, about one person in 40 lives in a place likely to be exposed to such flooding by the end of the century, absent significant changes.
Ashkenazi Jews (AJ), identified as Jewish individuals of Central- and Eastern European ancestry, form the largest genetic isolate in the United States. AJ demonstrate distinctive genetic characteristics1, 2, including high prevalence of autosomal recessive diseases and relatively high frequency of alleles that confer a strong risk of common diseases, such as Parkinson’s disease3and breast and ovarian cancer4. Several recent studies have employed common polymorphisms5,-13 to characterize AJ as a genetically distinct population, close to other Jewish populations as well as to present-day Middle Eastern and European populations. Previous analyses of recent AJ history highlighted a narrow population bottleneck of only hundreds of individuals in late medieval times, followed by rapid expansion12, 14.
The AJ population is much larger and/or experienced a more severe bottleneck than other founder populations, such as Amish, Hutterites or Icelanders15, whose demographic histories facilitated a steady stream of genetic discoveries. This suggests the potential for cataloguing nearly all founder variants in a large extant population by sequencing a limited number of samples, who represent the diversity in the founding group (for example, ref. 16). Such a catalogue of variants can make a threefold contribution: First, it will enable clinical interpretation of personal genomes in the sizeable AJ population by distinguishing between background variation and recent, potentially more deleterious mutations. Second, it will improve disease mapping in AJ by increasing the accuracy of imputation. Third, the ability to extensively sample a population with ancient roots in the Levant is expected to provide insights regarding the histories of both Middle Eastern and European populations.
Now a team of scientists report high-depth sequencing of 128 complete genomes of AJ controls. Compared with European samples, our AJ panel has 47% more novel variants per genome and is eightfold more effective at filtering benign variants out of AJ clinical genomes. Reconstruction of recent AJ history from such data confirms a recent bottleneck of merely ≈350 individuals. Modeling of ancient histories for AJ and European populations using their joint allele frequency spectrum determines AJ to be an even admixture of European and likely Middle Eastern origins. The researchers date the split between the two ancestral populations to ≈12–25 Kyr, suggesting a predominantly Near Eastern source for the repopulation of Europe after the Last Glacial Maximum.
Lately there's been news of a radical new theory proposing that the universe began from a hyper-dimensional black hole. Most of the reports seem to stem from an article posted a while back on the Nature blog, which references the original paper. So let's have a little reality check.
No one is abandoning the big bang model. The original paper hasn't even been peer reviewed yet and the paper doesn't present a radical new theory to overturn the big bang. What the paper is actually about is higher-dimensional gravitational theory.
The standard theory of gravity (general relativity) describes our universe as a geometry of three-dimensional space with one dimension of time. This is sometimes called 3 + 1 space, and it gives a very accurate description of the universe we observe. But theorists like to play around with alternative models to see how they differ from regular general relativity. They may look at 2 + 1 space, a kind of flatland with time, or 2 + 2, with two time dimensions. There isn't necessarily anything "real" about these models, and there certainly isn't any experimental evidence to support anything other than 3 + 1 gravity, but alternative models are useful because they help us gain a deeper understanding of general relativity. In this particular paper, the authors were exploring 4 + 1 gravity. That is, a five-dimensional universe with 4 spatial dimensions and 1 time.
Back in 2000, another team of authors proposed a model where our regular 3 + 1 gravity could be treated as a brane within a larger 4 + 1 universe. It is similar to the way a 2 + 1 universe could be imagined as a 2-dimensional surface (the brane) within our 3-dimensional space. In the 2000 paper, the authors showed that a particular 4 + 1 universe with a 3 + 1 brane could give rise to the type of gravity we actually see.
The new paper takes this model one step further. In it, the authors show that 4 + 1 gravity allows for the existence of black holes. So if a 4 + 1 universe had large stars, some of those stars could collapse into a 4-dimensional "hyper black hole". Like black holes in regular general relativity, these hyper black holes would have a central "singularity" of extremely dense and hot matter/energy. The authors then went on to show that a hyper black hole with the right conditions could not only create a three-dimensional brane, but the new brane would look very similar to the early universe we actually observe.
Water was crucial to the rise of life on Earth and is also important to evaluating the possibility of life on other planets. Identifying the original source of Earth's water is key to understanding how life-fostering environments come into being and how likely they are to be found elsewhere. New work found that much of our solar system's water likely originated as ices that formed in interstellar space.
Water is found throughout our Solar System. Not just on Earth, but on icy comets and moons, and in the shadowed basins of Mercury. Water has been found included in mineral samples from meteorites, the Moon, and Mars.
Comets and asteroids in particular, being primitive objects, provide a natural "time capsule" of the conditions during the early days of our Solar System. Their ices can tell scientists about the ice that encircled the Sun after its birth, the origin of which was an unanswered question until now.
In its youth, the Sun was surrounded by a protoplanetary disk, the so-called solar nebula, from which the planets were born. But it was unclear to researchers whether the ice in this disk originated from the Sun's own parental interstellar molecular cloud, from which it was created, or whether this interstellar water had been destroyed and was re-formed by the chemical reactions taking place in the solar nebula.
"Why this is important? If water in the early Solar System was primarily inherited as ice from interstellar space, then it is likely that similar ices, along with the prebiotic organic matter that they contain, are abundant in most or all protoplanetary disks around forming stars," Alexander explained.
"But if the early Solar System's water was largely the result of local chemical processing during the Sun's birth, then it is possible that the abundance of water varies considerably in forming planetary systems, which would obviously have implications for the potential for the emergence of life elsewhere."
Over the last decade, great enthusiasm has evolved for microRNA (miRNA) therapeutics. Part of the excitement stems from the fact that a miRNA often regulates numerous related mRNAs. As such, modulation of a single miRNA allows for parallel regulation of multiple genes involved in a particular disease. While many studies have shown therapeutic efficacy using miRNA inhibitors, efforts to restore or increase the function of a miRNA have been lagging behind.
The miR‐29 family has gained a lot of attention for its clear function in tissue fibrosis. This fibroblast‐enriched miRNA family is downregulated in fibrotic diseases which induces a coordinate increase of many extracellular matrix genes. Here, we show that intravenous injection of synthetic RNA duplexes can increase miR‐29 levels in vivo for several days. Moreover, therapeutic delivery of these miR‐29 mimics during bleomycin‐induced pulmonary fibrosis restores endogenous miR‐29 function whereby decreasing collagen expression and blocking and reversing pulmonary fibrosis. Our data support the feasibility of using miRNA mimics to therapeutically increase miRNAs and indicate miR‐29 to be a potent therapeutic miRNA for treating pulmonary fibrosis.
Fatigue, weight gain, chills, hair loss, anxiety, excessive perspiration -- these symptoms are a few of the signs that the thyroid gland has gone haywire. Harnessing electron microscopy to track the inner hair cells of the cochlea in two groups of mice, new research points to an additional complication caused by an imbalance in the thyroid gland: congenital deafness.
The study, published in Mammalian Genome, was conducted by Prof. Karen B. Avraham and Dr. Amiel Dror of the Department of Human Molecular Genetics and Biochemistry at TAU's Sackler School of Medicine. Using state-of-the-art imaging, the researchers found that congenital deafness can be caused by an absence of a thyroid hormone during development.
"Since our laboratory mainly focuses on the system of the inner ear, the study of a system such as the thyroid gland was new to us and therefore challenging," said Dr. Dror. "My curiosity as to how these two systems interact together to develop normal hearing led to this multidisciplinary study."
The researchers used mouse populations to study a form of congenital deafness that affects humans. Harnessing electron microscopy at the Sackler Cellular & Molecular Imaging Center, researchers tracked the inner hair cells of the cochlea (the auditory portion of the inner ear) in two groups -- control (wild) mice and mutant (congenitally deaf) mice. Inner-ear hair bundles in the affected mice were labelled with bright colors to highlight the disorganization of the ear's hair cells.
Examination of the inner ear showed a spectrum of structural and molecular defects consistent with hypothyroidism or disrupted thyroid hormone action. The researchers' analysis of the images revealed defective formation of the mice's thyroid glands: labelled thyroid follicles did not grow or grew incompletely.
"Our work demonstrated that normal hearing fails to develop when thyroid hormone availability is insufficient as a result of a genetic mutation," said Dr. Dror. "Our model provides a platform to test therapeutic approaches in order to prevent hearing loss before it occurs. There is still long way ahead before we get to the point of practical treatments with our research, but we believe we are moving in the right direction."
A trio of researchers with Germany's Museum für Naturkunde, Leibniz-Institut für Evolutions und Biodiversitätsforschung, has found evidence of limb regeneration in a 300 million year old amphibian fossil, which suggests that the ability to regenerate entire limbs by such creatures is not restricted to modern salamanders. In their paper published in Proceedings of the Royal Society B: Biological Sciences, Nadia Fröbisch, Constanze Bickelmann and Florian Witzmann describe the fossil they've been studying and why they believe it was able to regenerate its limbs.
Scientists believe that salamanders are the only modern four-legged animals that can regenerate entire limbs throughout their lives. What's not clear, however, despite a great deal of research, is if the ability is a recent evolutionary trait or if it came about long ago and has been passed along for many years. The findings by the researchers with this latest effort suggest the latter—the fossil appears to be an ancient relative of the salamander.
The researchers note that when modern salamanders lose a limb, the replacement that grows back doesn't always look just like the original—sometimes there are odd bumps or scars or digits fused back together. This is particularly so if a salamander looses the same limb more than once. In examining the amphibian fossil, (Micromelerpeton, found in northwest Germany) the researchers found the same odd characteristic in the toes—there was an extra partly fused one, suggesting very strongly that the creature had lost a toe and had re-grown a replacement.
Finding regenerative ability in such an ancient creature begs the question of why more tetrapod species don't have the ability today. The researchers suggest that the ability to re-grow lost limbs was perhaps lost over time or evolved into something else entirely as it became a trait that was no longer needed, or because it took up too much resources.
Gaining an evolutionary perspective on limb regeneration might help researchers in other areas that are attempting to find out if limb replacement can be caused to come about in other animals, particularly humans, through some unknown mechanism. Learning how salamanders developed the ability might help modern researchers repeat the process.
Earth's magnetic north and south poles have flip-flopped many times in our planet's history—most recently, around 780,000 years ago. Geophysicists who study the magnetic field have long thoughtthat the poles may be getting ready to switch again, and based on new data, it might happen earlier than anyone anticipated.
The European Space Agency's satellite array dubbed “Swarm” revealed that Earth's magnetic field is weakening 10 times faster than previously thought, decreasing in strength about 5 percent a decade rather than 5 percent a century. A weakening magnetic field may indicate an impending reversal, which scientists predict could begin in less than 2,000 years. Magnetic north itself appears to be moving toward Siberia.
Geophysicists do not yet fully understand the process of geomagnetic reversals, but they agree that our planet's field is like adipole magnet. Earth's center consists of an inner core of solid iron and an outer core of liquid iron, a strong electrical conductor. The liquid iron in the outer core is buoyant, and as it heats near the inner core, it rises, cools off and then sinks. Earth's rotation twists this moving iron liquid and generates a self-perpetuating magnetic field with north and south poles.
Yeast. They already participate in producing some of the most popular pain-killing substances around: beer and wine. Now, scientists have engineered yeast that can also make one of the most powerful analgesics:morphine. Their work is in the journal Nature Chemical Biology. [Kate Thodey, Stephanie Galanie and Christina D. Smolke, A microbial biomanufacturing platform for natural and semisynthetic opioids]
Experimenting within quantum theory is an extremely complex process, where common intuitions are regularly inverted within shifting reality. Over the years several quantum features and methods of their study have been identified. Now scientists have investigated a new set of assumptions and proposed a novel experiment, to test the consequences of making quantum theory more intuitive.
"While quantum theory is the science behind almost all of our technology, its disconnect with our everyday intuitions is still worrisome and actively researched," says lead author Associate Professor Daniel Terno.
"How do you find your way in a reality which is shifting, where the opposites are allowed to coexist? Moreover, how do you conduct experiments in it? These are the questions that must be answered when dealing with the floating world of quantum mechanics."
Throughout the development of quantum theory, a set of reasonable ideas has led to strange paradoxes, such as the famous Schrodinger's cat, which is neither dead nor alive.
Using this wave-particle duality as their starting point, the research team investigated a new and more comprehensible set of assumptions:
In taking these assumptions and applying them to an experiment, where the measuring device is controlled by a Schrodinger's cat-like state, the research team reached some perplexing paradoxes.
"Only after the cat was found to be dead or alive were we able to tell if what we did was to look for a particle or for a wave," says Associate Professor Terno. "Then these three innocent-looking ideas result in predictions that would contradict an experiment. The universe simply does not work like that: you can see things to be real, or certain, but not both."
Then the researchers tweaked their initial assumptions, replacing the third assumption with the requirement that how you set your detectors does not affect the system you study before they interact. This tweak lead to another strange result: it is not only that our quantum world is not like that, but such a combination cannot be realized in any universe.
"We can just repeat after Alice: things get stranger and stranger"
A device called the Rochester Cloak uses an array of lenses to bend light, effectively rendering what is on the other side invisible to the eye. And you can try it for yourself.
One of the problems with the cloaking devices developed to date -- and it's a big one -- is that they really only work if both the viewer and whatever is being cloaked remain still. This, of course, is not entirely practical, but a difficult problem to solve.
For the first time, researchers have made a cloaking device that works multi-directionally in three dimensions -- using no specialized equipment, but four standard lenses.
"There've been many high tech approaches to cloaking and the basic idea behind these is to take light and have it pass around something as if it isn't there, often using high-tech or exotic materials," said professor of physics at Rochester University John Howell, who developed the Rochester Cloak with graduate student Joseph Choi.
"This is the first device that we know of that can do three-dimensional, continuously multidirectional cloaking, which works for transmitting rays in the visible spectrum," Choi added.
As well as at least partially solving the viewpoint problem, the Rochester cloak also leaves the background undisturbed, without any warping, as has appeared in other devices. This invisibility has a range of around 15 degrees; as you can see in the video below at around the two-minute mark when Choi places his hand in between the lenses, the dead centre of the field is not included.
Scientists at IBM Research have created by far the most advanced neuromorphic (brain-like) computer chip to date. The chip, called TrueNorth, consists of 1 million programmable neurons and 256 million programmable synapses across 4096 individual neurosynaptic cores. Built on Samsung’s 28nm process and with a monstrous transistor count of 5.4 billion, this is one of the largest and most advanced computer chips ever made. Perhaps most importantly, though, TrueNorth is incredibly efficient: The chip consumes just 72 milliwatts at max load, which equates to around 400 billion synaptic operations per second per watt — or about 176,000 times more efficient than a modern CPU running the same brain-like workload, or 769 times more efficient than other state-of-the-art neuromorphic approaches. Yes, IBM is now a big step closer to building a brain on a chip.
The animal brain (which includes the human brain, of course), as you may have heard before, is by far the most efficient computer in the known universe. As you can see in the graph below, the human brain has a “clock speed” (neuron firing speed) measured in tens of hertz, and a total power consumption of around 20 watts. A modern silicon chip, despite having features that are almost on the same tiny scale as biological neurons and synapses, can consume thousands or millions times more energy to perform the same task as a human brain. As we move towards more advanced areas of computing, such as artificial general intelligence and big data analysis — areas that IBM just happens to be deeply involved with — it would really help if we had a silicon chip that was capable of brain-like efficiency.
75 billion. That's the potential size of the Internet Things sector, which could become a multi-trillion dollar market by the end of the decade.
That's a very big number of devices that Morgan Stanley has extrapolated from a Cisco report that details how many devices will be connected to the Internet of Things by 2020. That's 9.4 devices for every one of the 8 billion people that's expected to be around in seven years.
To help put that into more perspective, back in Cisco also came out with the number of devices it thinks were connected to the Internet in 2012, a number Cisco's Rob Soderbery placed at 8.7 billion. Most of the devices at the time, he acknowledged were the PCs, laptops, tablets and phones in the world. But other types of devices will soon dominate the collection of the Internet of Things, such as sensors and actuators.
By the end of the decade, a nearly nine-fold increase in the volume of devices on the Internet of Things will mean a lot of infrastructure investment and market opportunities will available in this sector. And by "a lot," I mean ginourmous. In an interview with Barron's, Cisco CEO John Chambers figures that will translate to a $14-trillion industry.
Granted, Cisco has a lot of reasons to be bullish about the prospect of the Internet of Things: with product offerings in the router and switch space and a recent keen interest on building intelligent routing and application platforms right inside those devices, Cisco stands to gain a lot of business if it can get itself out in front of this newfangled Internet of Things.
It's not just Cisco talking up the Internet of Things: late last week, Morgan Stanley published a big 29-page research note on the topic that sought to at once define the Internet of Things and also quantify its size, growth and potential to make money.
See also: Cisco Hearts Internet Of Things
The Ebola virus causes an acute, serious illness which is often fatal if untreated. Ebola virus disease (EVD) first appeared in 1976 in 2 simultaneous outbreaks, one in Nzara, Sudan, and the other in Yambuku, Democratic Republic of Congo. The latter occurred in a village near the Ebola River, from which the disease takes its name.
A Virginia Tech geobiologist with collaborators from the Chinese Academy of Sciences have found evidence in the fossil record that complex multicellularity appeared in living things about 600 million years ago – nearly 60 million years before skeletal animals appeared during a huge growth spurt of new life on Earth known as the Cambrian Explosion.
The discovery published online Wednesday in the journal Nature contradicts several longstanding interpretations of multicellular fossils from at least 600 million years ago.
"This opens up a new door for us to shine some light on the timing and evolutionary steps that were taken by multicellular organisms that would eventually go on to dominate the Earth in a very visible way," said Shuhai Xiao, a professor of geobiology in the Virginia Tech College of Science. "Fossils similar to these have been interpreted as bacteria, single-cell eukaryotes, algae, and transitional forms related to modern animals such as sponges, sea anemones, or bilaterally symmetrical animals. This paper lets us put aside some of those interpretations."
In an effort to determine how, why, and when multicellularity arose from single-celled ancestors, Xiao and his collaborators looked at phosphorite rocks from the Doushantuo Formation in central Guizhou Province of South China, recovering three-dimensionally preserved multicellular fossils that showed signs of cell-to-cell adhesion, differentiation, and programmed cell death—qualities of complex multicellular eukaryotes such as animals and plants.
The discovery sheds light on how and when solo cells began to cooperate with other cells to make a single, cohesive life form. The complex multicellularity evident in the fossils is inconsistent with the simpler forms such as bacteria and single-celled life typically expected 600 million years ago.
Scientists have found the beginnings of life-bearing chemistry at the centre of the galaxy. Iso-propyl cyanide has been detected in a star-forming cloud 27,000 light-years from Earth. Its branched carbon structure is closer to the complex organic molecules of life than any previous finding from interstellar space.
The discovery suggests the building blocks of life may be widespread throughout our galaxy. Various organic molecules have previously been discovered in interstellar space, but i-propyl cyanide is the first with a branched carbon backbone.
The branched structure is important as it shows that interstellar space could be the origin of more complex branched molecules, such as amino acids, that are necessary for life on Earth. Dr Arnaud Belloche from the Max Planck Institute for Radio Astronomy is lead author of the research, which appears in the journal Science.
"Amino acids on Earth are the building blocks of proteins, and proteins are very important for life as we know it. The question in the background is: is there life somewhere else in the galaxy?"
Astronomers using data from the NASA/ESA Hubble Space Telescope, the Spitzer Space Telescope, and the Kepler Space Telescope have discovered clear skies and steamy water vapour on a planet outside our Solar System. The planet, known as HAT-P-11b, is about the size of Neptune, making it the smallest exoplanet ever on which water vapour has been detected. The results will appear in the online version of the journal Nature on 24 September 2014.
The discovery is a milestone on the road to eventually finding molecules in the atmospheres of smaller, rocky planets more akin to Earth. Clouds in the atmospheres of planets can block the view of what lies beneath them. The molecular makeup of these lower regions can reveal important information about the composition and history of a planet. Finding clear skies on a Neptune-size planet is a good sign that some smaller planets might also have similarly good visibility.
"When astronomers go observing at night with telescopes, they say 'clear skies' to mean good luck," said Jonathan Fraine of the University of Maryland, USA, lead author of the study. "In this case, we found clear skies on a distant planet. That's lucky for us because it means clouds didn't block our view of water molecules."
HAT-P-11b is a so-called exo-Neptune — a Neptune-sized planet that orbits another star. It is located 120 light-years away in the constellation of Cygnus (The Swan). Unlike Neptune, this planet orbits closer to its star, making one lap roughly every five days. It is a warm world thought to have a rocky core, a mantle of fluid and ice, and a thick gaseous atmosphere. Not much else was known about the composition of the planet, or other exo-Neptunes like it, until now.
"We set out to look at the atmosphere of HAT-P-11b without knowing if its weather would be cloudy or not," said Nikku Madhusudhan, from the University of Cambridge, UK, part of the study team. "By using transmission spectroscopy, we could use Hubble to detect water vapour in the planet. This told us that the planet didn't have thick clouds blocking the view and is a very hopeful sign that we can find and analyze more cloudless, smaller, planets in the future. It is groundbreaking!"
Before the team could celebrate they had to be sure that the water vapour was from the planet and not from cool starspots — "freckles" on the face of stars — on the parent star. Luckily, Kepler had been observing the patch of sky in which HAT-P-11b happens to lie for years. Those visible-light data were combined with targeted infrared Spitzer observations. By comparing the datasets the astronomers could confirm that the starspots were too hot to contain any water vapour, and so the vapour detected must belong to the planet.
The results from all three telescopes demonstrate that HAT-P-11b is blanketed in water vapour, hydrogen gas, and other yet-to-be-identified molecules. So in fact it is not only the smallest planet to have water vapour found in its atmosphere but is also the smallest planet for which molecules of any kind have been directly detected using spectroscopy . Theorists will be drawing up new models to explain the planet's makeup and origins.
A quantum effect in which excited atoms team up to emit an enhanced pulse of light can be turned on its head to create 'superabsorbing' systems that could make the 'ultimate camera pixel'.
'Superradiance', a phenomenon where a group of atoms charged up with energy act collectively to release a far more intense pulse of light than they would individually, is well-known to physicists. In theory the effect can be reversed to create a device that draws in light ultra-efficiently. This could be revolutionary for devices ranging from digital cameras to solar cells. But there's a problem: the advantage of this quantum effect is strongest when the atoms are already 50% charged -- and then the system would rather release its energy back as light than absorb more.
Now a team led by Oxford University theorists believes it has found the solution to this seemingly fundamental problem. Part of the answer came from biology. 'I was inspired to study ring molecules, because they are what plants use in photosynthesis to extract energy from the Sun,' said Kieran Higgins of Oxford University's Department of Materials, who led the work. 'What we then discovered is that we should be able to go beyond nature's achievement and create a 'quantum superabsorber'.'
A report of the research is published in Nature Communications.
At the core of the new design is a molecular ring, which is charged to 50% by a laser pulse in order to reach the ideal superabsorbing state. 'Now we need to keep it in that condition' notes Kieran. For this the team propose exploiting a key property of the ring structure: each time it absorbs a photon, it becomes receptive to photons of a slightly higher energy. Charging the device is like climbing a ladder whose rungs are increasingly widely spaced.
'Let's say it starts by absorbing red light from the laser,' said Kieran, 'once it is charged to 50% it now has an appetite for yellow photons, which are higher energy. And we'd like it to absorb new yellow photons, but NOT to emit the stored red photons.' This can be achieved by embedding the device into a special crystal that suppresses red light: it makes it harder for the ring to release its existing energy, so trapping it in the 50% charged state.
The final ingredient of the design is a molecular 'wire' that draws off the energy of newly absorbed photons. 'If you built a system with a capacity of 100 energy units the idea would be to 'half-charge' it to 50 units, and the wire would then 'harvest' every unit over 50,' said Kieran. 'It's like an overflow pipe in plumbing -- it is engineered to take the energy level down to 50, but no lower.' This means that the device can handle the absorption of many photons in quick succession when it is exposed to a bright source, but in the dark it will simply sit in the superabsorbing state and efficiently grab any rare passing photon.
Princeton University researchers have developed a new method to increase the brightness, efficiency and clarity of LEDs, which are widely used on smartphones and portable electronics as well as becoming increasingly common in lighting.
Using a new nanoscale structure, the researchers, led by electrical engineering professor Stephen Chou, increased the brightness and efficiency of LEDs made of organic materials (flexible carbon-based sheets) by 58 percent. The researchers also report their method should yield similar improvements in LEDs made in inorganic (silicon-based) materials used most commonly today.
The method also improves the picture clarity of LED displays by 400 percent, compared with conventional approaches. In an article published online August 19 in the journal Advanced Functional Materials, the researchers describe how they accomplished this by inventing a technique that manipulates light on a scale smaller than a single wavelength.
"New nanotechnology can change the rules of the ways we manipulate light," said Chou, who has been working in the field for 30 years. "We can use this to make devices with unprecedented performance."
Bacillus anthracis bacteria have very efficient machinery for injecting toxic proteins into cells, leading to the potentially deadly infection known as anthrax. A team of MIT researchers has now hijacked that delivery system for a different purpose: administering cancer drugs.
“Anthrax toxin is a professional at delivering large enzymes into cells,” says Bradley Pentelute, the Pfizer-Laubauch Career Development Assistant Professor of Chemistry at MIT. “We wondered if we could render anthrax toxin nontoxic, and use it as a platform to deliver antibody drugs into cells.”
In a paper appearing in the journal ChemBioChem, Pentelute and colleagues showed that they could use this disarmed version of the anthrax toxin to deliver two proteins known as antibody mimics, which can kill cancer cells by disrupting specific proteins inside the cells. This is the first demonstration of effective delivery of antibody mimics into cells, which could allow researchers to develop new drugs for cancer and many other diseases, says Pentelute, the senior author of the paper.
Antibodies — natural proteins the body produces to bind to foreign invaders — are a rapidly growing area of pharmaceutical development. Inspired by natural protein interactions, scientists have designed new antibodies that can disrupt proteins such as the HER2 receptor, found on the surfaces of some cancer cells. The resulting drug, Herceptin, has been successfully used to treat breast tumors that overexpress the HER2 receptor.
Several antibody drugs have been developed to target other receptors found on cancer-cell surfaces. However, the potential usefulness of this approach has been limited by the fact that it is very difficult to get proteins inside cells. This means that many potential targets have been “undruggable,” Pentelute says.
“Crossing the cell membrane is really challenging,” he says. “One of the major bottlenecks in biotechnology is that there really doesn’t exist a universal technology to deliver antibodies into cells.”
For inspiration to solve this problem, Pentelute and his colleagues turned to nature. Scientists have been working for decades to understand how anthrax toxins get into cells; recently researchers have started exploring the possibility of mimicking this system to deliver small protein molecules as vaccines.
The anthrax toxin has three major components. One is a protein called protective antigen (PA), which binds to receptors called TEM8 and CMG2 that are found on most mammalian cells. Once PA attaches to the cell, it forms a docking site for two anthrax proteins called lethal factor (LF) and edema factor (EF). These proteins are pumped into the cell through a narrow pore and disrupt cellular processes, often resulting in the cell’s death.
However, this system can be made harmless by removing the sections of the LF and EF proteins that are responsible for their toxic activities, leaving behind the sections that allow the proteins to penetrate cells. The MIT team then replaced the toxic regions with antibody mimics, allowing these cargo proteins to catch a ride into cells through the PA channel.
The United States has plenty of strong winds offshore, but it has struggled to harness them for energy.
In theory, the potential is tremendous. Including harder-to-reach deep-water sites, the offshore territory of the United States has the capacity to generate an estimated 4,200 gigawatts of electricity, enough to supply four times the nation’s current needs. But before the field can take off, proponents will have to prove that offshore wind can compete financially against other energy sources, and can clear the thicket of state and federal regulations that govern projects in coastal waters.
“I don’t think we’re looking at easy street here,” says Walt Musial, a long-time offshore-wind researcher at the National Renewable Energy Laboratory in Louisville, Colorado. “We really need to demonstrate that it can be done.”
No project encapsulates the challenges facing offshore wind power better than Cape Wind, being developed by Energy Management of Boston, Massachusetts. The venture aims to take advantage of the strong winds and relatively calm waters of Nantucket Sound near Cape Cod, Massachusetts, some 350 kilometres southwest of Castine.
The plan for Cape Wind consists of 130 turbines, each standing nearly 80 metres tall, over an area of 65 square kilometres. Energy Management says that the completed wind farm will have a capacity of 468 megawatts, able to produce 75% of the electricity for Cape Cod and the nearby islands of Martha’s Vineyard and Nantucket.
But the project has faced strong opposition for more than a decade. Organizations including the non-profit group Save Our Sound have brought dozens of lawsuits against Cape Wind, claiming that the project would harm birds and other wildlife, increase electricity rates for consumers and endanger aeroplanes flying into local airspace.Except for one temporary decision, all of the judicial rulings have been in favour of Cape Wind. Spokesperson Mark Rodgers says that even with court appeals coming, the project intends to commence construction by spring 2015. “There are no merits to any of these legal complaints,” he says.
Cape Wind has already broken new ground by being the first US offshore wind project to complete a major environmental assessment. That study — thousands of pages long — and independent analyses have helped to appease some groups that were sceptical of the initial proposal.