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First, in 2012, researchers observed extraordinarily high densities of the sunflower star Pycnopodia helianthoides on the rocky slopes at various location of the Pacific Northwest. At some sites these stars occupied a wide band in the shallow subtidal zone with densities of up 12 per square meter. Scientists were unable to explain how or why such high densities had developed.
Toward the end of August, 2013, divers began seeing sunflower stars dying in unusual numbers. They reported hundreds that appeared to be disintegrating, their rays falling off and internal organs protruding through ruptures in the body wall. Dubbed “the wasting syndrome,” this phenomenon quickly spread through the entire sunflower star population, killing an estimated tens of thousands in Howe Sound, BC alone. By the end of October, virtually all sunflower stars at most locations were dead.
While sunflower stars took the brunt of the wasting syndrome, other sea stars were also dying, including the morning sun star Solaster dawsoni, the giant pink star Pisaster brevispinus, the mottled star Evasterias troschelii, the purple/ochre star Pisaster ochraceus, the vermilion star Mediaster aequalis, the rainbow star Orthasterias koehleri, the striped sun star Solaster stimpsoni and the leather star Dermasterias imbricata. These stars were more widely distributed and less numerous than Pycnopodia helianthoides, yet they were dying in a similar way as the sunflower stars.
The mysterious illness has the potential to wipe out all the sea stars along the west coast of North America, said Paula Romagosa, a marine biologist and curator at the Shaw Ocean Discovery Centre in Sidney, B.C.
“Events like this have happened before but on a much smaller scale. We’ve never seen one of this magnitude.”
The loss of the species is troubling because sea stars are omnivores and will eat anything, including smaller sea stars. “Everything in the food chain below them is going to be affected — all the clams too,” Romagosa said.
“There could potentially be an overpopulation of those species down the food chain, and an overpopulation usually leads to mass mortality from bacterial infections.
The virus has not yet been identified, but it’s under study at Vancouver Aquarium and some California universities. “We’re diving as much as possible, trying to document it,” Romagosa said.
Adults are affected more than juveniles, “but in general, it’s affecting everyone,” she said. Some populations are completely wiped out, including one near the Seattle Aquarium. “You can see where the sea stars have died and there’s nothing left,” Romagosa said.
The marine environment has proven to be a valuable source of interesting and unusual natural products with a diverse range of biological activities. Of particular interest are marine snails belonging to the genus Conus, which contains an estimated 700 species, each possessing a unique cocktail of pharmacologically active peptides within its venom [1,2,3]. These marine snails have evolved into efficient predators, using their venom to hunt and paralyze worms, molluscs or fish. Conotoxins, isolated from the venom ducts of cone snails, constitute a large family of small, disulfide-rich peptides that have evolved to target a range of ion channels and receptors throughout the nervous system, usually with high potency and selectivity [4,5,6,7]. As such, many of these conotoxins have been used to gain further information about their target at the pharmacological, physiological or structural level [8,9,10,11]. They are relatively small peptides, typically eight to thirty amino acid residues in length that have been divided into different structural and pharmacological classes. A nomenclature for the conotoxins classifies the peptides according to the source, cysteine framework and biological target . The more recent availability of nucleic acid sequences from cDNA and transcriptomics analyses is enabling systematic classification into superfamilies on the basis of pre- and pro-peptide sequences [13,14].
Conotoxins serve not only as valuable pharmacological tools but potential drug candidates. While several conotoxins have advanced to clinical trials [15,16,17], ω-conotoxin MVIIA (ziconotide) was the first to be approved by the FDA for therapeutic use in humans . Marketed as Prialt®, it possesses potent and selective N-type calcium channel activity and is used to treat patients suffering from severe chronic pain . Although Prialt® represents a major milestone for conotoxins, its use is limited to intrathecal administration. Nonetheless, it highlights the potential of neurotoxic peptides as starting points for the development of therapeutics. Despite their desirable biological activities, peptides generally have several limitations that have restricted their progression as drug candidates, amongst which are short circulating half-life, poor proteolytic stability, and low oral bioavailability [20,21]. The challenge remains to capture the favorable bioactive properties of peptide toxins within drug-like molecules that can be administered in the clinic. This review summarizes current strategies for the development of conotoxins and their mimetics as leads for novel therapeutics.
The Astrophysics Source Code Library (ASCL) is a free, on-line reference library for source codes of all sizes that are of interest to astrophysicists. All ASCL source codes have been used to generate results published in or submitted to a refereed journal. No ASCL code is guaranteed to be correct.
ASCL was founded in March 1999. In 2010, it was moved from its former site at ASCL.net to its current home. Source codes are increasingly important for the advancement of science in general and astrophysics in particular.
Panspermia - the idea that organisms can "hitchhike" around the solar system on comets and debris from meteor strikes - has long fascinated astronomers. But thanks to advances in computing, astrobiologists are now able to simulate these journeys and follow potential stowaways as they hitch around the Solar System.
In this new study, researchers first estimated the number of rocks bigger than 3m ejected from Earth by major impacts. Perhaps the most famous of these impacts was at Chicxulub in Mexico about 66 million years ago - when an object the size of a small city collided with Earth. The impact has been blamed for the mass extinction of the dinosaurs, triggering volcanic eruptions and wildfires which choked the planet with smoke and dust. It also launched about 70 billion kg of rock into space - 20,000kg of which could have reached Juper moon Europa. And the chances that a rock big enough to harbor life arrived are "better than 50/50", researchers estimate. Could Earthlings be swimming in the icy oceans of Europa?
Three meters is the minimum they think necessary to shield microbes from the Sun's radiation over a journey lasting up to 10 million years. They then mapped the likely fate of these voyagers. Many simply hung around in Earth orbit, or were slowly drawn back down.
Others were pulled into the Sun, or sling-shotted out of the Solar System entirely. Yet a small but significant number made it all the way to alien worlds which might welcome life. About six rocks even made it as far as Europa, a satellite of Jupiter with a liquid ocean covered in an icy crust. But could living organisms actually survive these epic trips?
"We find that rock capable of carrying life has likely transferred from both Earth and Mars to all of the terrestrial planets in the solar system and Jupiter," says lead author Rachel Worth, of Penn State University.
On Mars, there is little evidence of flowing water during the last 3.5bn years - the likeliest window for Earth life to arrive.
The first space travellers? Bacterial endospores can survive for millions of years. But what if the reverse trip took place? The early Martian atmosphere appears to have been warm and wet - prime conditions for the development of life.
And if Martian microbes ever did exist, transfer to Earth is "highly probable" due to the heavy traffic of meteorites between both planets.
"Billions have fallen on Earth from Mars since the dawn of our planetary system. It is even possible that life on Earth originated on Mars," says Ms. Worth. While her team are not the first to calculate that panspermia is possible, their 10-million-year simulation is the most extended yet, said astrobiologist Prof. Jay Melosh, of Purdue University. "The study strongly reinforces the conclusion that, once large impacts eject material from the surface of a planet such as the Earth or Mars, the ejected debris easily finds its way from one planet to another", he says.
"The Chicxulub impact itself might not have been a good candidate because it occurred in the ocean (50 to 500m deep water) and, while it might have ejected a few sea-surface creatures, like ammonites, into space, it would not likely have ejected solid rocks. "I sometimes joke that we might find ammonite shells on the Moon from that event.
"But other large impacts on the Earth may indeed have ejected rocks into interplanetary space." Another independent expert on panspermia, Mauricio Reyes-Ruiz of the National Autonomous University of Mexico, said the new findings were "very significant".
"The fact such different pathways exist for the interchange of material between Earth and bodies in the Solar System suggests that if life is ever found, it may very well turn out to be our very, very distant relatives," he said.
Researchers Unveil First Results in Adult ALL Patients: All Five Patients Had Complete Response to Therapy
Genetically Modified Cells Produce Long-Term Remissions, Persist in Patients' Bodies with Vaccine-Like Activity for More than Three Years
Three and a half years after beginning a clinical trial which demonstrated the first successful and sustained use of genetically engineered T cells to fight leukemia, a research team from the Perelman School of Medicine at the University of Pennsylvania and the Children’s Hospital of Philadelphia will today announce the latest results of studies involving both adults and children with advanced blood cancers that have failed to respond to standard therapies. The findings from the first 59 patients who received this investigational, personalized cellular therapy, known as CTL019, will be presented during the American Society of Hematology’s Annual Meeting and Exposition in New Orleans.
Two of the first three chronic lymphocytic leukemia (CLL) patients who participated in the study, which started in the summer of 2010, remain in remission, with tests revealing reprogrammed cells still circulating in their bodies, on guard to combat tumor cells that may reappear in the future. Additional highlights of the new research results include an 89 percent complete response rate among adult and pediatric patients with acute lymphoblastic leukemia (ALL).
“In a very short time, we’ve learned so much about how CTL019 works and how powerful it can be,” said the research team’s leader, Carl H. June, MD, Richard W. Vague Professor in Immunotherapy in the department of Pathology and Laboratory Medicine and director of Translational Research in Penn’s Abramson Cancer Center. “Our findings show that the human immune system and these modified ‘hunter’ cells are working together to attack tumors in an entirely new way.”
New research by Kevin Trenberth and John Fasullo of the National Center for Atmospheric Research investigates how the warming of the Earth's climate has behaved over the past 15 years compared with the previous few decades. They conclude that while the rate of increase of average global surface temperatures has slowed since 1998, melting of Arctic ice, rising sea levels, and warming oceans have continued apace.
The widespread mainstream media focus on the slowed global surface warming has led some climate scientists like Trenberth and Fasullo to investigate its causes and how much various factors have contributed to the so-called 'pause' or 'hiatus.' However, the authors note that while the increase in global temperatures has slowed, the oceans have taken up heat at a faster rate since the turn of the century.
Over 90 percent of the overall extra heat goes into the oceans, with only about 2 percent heating the Earth's atmosphere. The myth of the 'pause' is based on ignoring 98 percent of global warming and focusing exclusively on the one bit that's slowed.
A team in South Africa has discovered the first definitive evidence of a comet strike on Earth some 28 million years ago.
A team in South Africa has discovered the first definitive evidence of a comet strike on Earth some 28 million years ago. It’s believed to have blown up over what is now Egypt, heating up the Sahara sand to a temperature of up to 2000 degrees Celcius, annihilating everything in its path.
“Comets are unique, comets are extraordinary because they carry very pristine material from our outer solar system and well beyond. So, you literally have a travelling chemical factory, which enters our Earth’s atmosphere and explodes. The comet explodes, it shatters glass, it creates glass – molten glass – there is this lake of fire which creates a blast area of 6,000 square kilometers,” says Professor David Block.
A specimen of the glass is on display in Johannesburg, together with an unusual rock collected in the Sahara 20 years ago. It is filled with microscopic black diamonds, believed to be part of a comet’s nucleus.
The core of a comet is made up of material formed at the same time as our own solar system four and a half billion years ago. Scientists hope this discovery could help unlock some of the secrets of the formation of our solar system.
“NASA and ESA (European Space Agency) generally spend billions of dollars in designing spacecraft which can either send an impactor into the very nucleus of a comet. I think the incredible point about this discovery too is that you don’t need to go into space to collect the material, the material is right here,” said Professor Block.
A ten-dimensional theory of gravity makes the same predictions as standard quantum physics in fewer dimensions.
At a black hole, Albert Einstein's theory of gravity apparently clashes with quantum physics, but that conflict could be solved if the Universe were a holographic projection. A team of physicists has provided some of the clearest evidence yet that our Universe could be just one big projection.
In 1997, theoretical physicist Juan Maldacena proposed1 that an audacious model of the Universe in which gravity arises from infinitesimally thin, vibrating strings could be reinterpreted in terms of well-established physics. The mathematically intricate world of strings, which exist in nine dimensions of space plus one of time, would be merely a hologram: the real action would play out in a simpler, flatter cosmos where there is no gravity.
Maldacena's idea thrilled physicists because it offered a way to put the popular but still unproven theory of strings on solid footing — and because it solved apparent inconsistencies between quantum physics and Einstein's theory of gravity. It provided physicists with a mathematical Rosetta stone, a 'duality', that allowed them to translate back and forth between the two languages, and solve problems in one model that seemed intractable in the other and vice versa. But although the validity of Maldacena's ideas has pretty much been taken for granted ever since, a rigorous proof has been elusive.
In two papers posted on the arXiv repository, Yoshifumi Hyakutake of Ibaraki University in Japan and his colleagues now provide, if not an actual proof, at least compelling evidence that Maldacena’s conjecture is true. In one paper2, Hyakutake computes the internal energy of a black hole, the position of its event horizon (the boundary between the black hole and the rest of the Universe), its entropy and other properties based on the predictions of string theory as well as the effects of so-called virtual particles that continuously pop into and out of existence. In the other3, he and his collaborators calculate the internal energy of the corresponding lower-dimensional cosmos with no gravity. The two computer calculations match. “It seems to be a correct computation,” says Maldacena, who is now at the Institute for Advanced Study in Princeton, New Jersey and who did not contribute to the team's work.
The findings “are an interesting way to test many ideas in quantum gravity and string theory”, Maldacena adds. The two papers, he notes, are the culmination of a series of articles contributed by the Japanese team over the past few years. “The whole sequence of papers is very nice because it tests the dual [nature of the universes] in regimes where there are no analytic tests.”
“They have numerically confirmed, perhaps for the first time, something we were fairly sure had to be true, but was still a conjecture — namely that the thermodynamics of certain black holes can be reproduced from a lower-dimensional universe,” says Leonard Susskind, a theoretical physicist at Stanford University in California who was among the first theoreticians to explore the idea of holographic universes.
Neither of the model universes explored by the Japanese team resembles our own, Maldacena notes. The cosmos with a black hole has ten dimensions, with eight of them forming an eight-dimensional sphere. The lower-dimensional, gravity-free one has but a single dimension, and its menagerie of quantum particles resembles a group of idealized springs, or harmonic oscillators, attached to one another.
Nevertheless, says Maldacena, the numerical proof that these two seemingly disparate worlds are actually identical gives hope that the gravitational properties of our Universe can one day be explained by a simpler cosmos purely in terms of quantum theory.
In the first 300 days of the Mars Science Laboratory surface mission, the Curiosity rover cruised around the planet's Gale Crater, collecting soil samples and investigating rock structures while the onboard Radiation Assessment Detector made detailed measurements of the radiation environment on the surface of Mars.
SwRI scientists published radiation surface dose rates from the first 300 days on Mars in Science online Dec. 9. Curiosity's Radiation Assessment Detector observed a spike in the radiation dose associated with one hard solar energetic particle event and three dips in radiation associated with soft interplanetary coronal mass ejections, which provided magnetic shielding against galactic cosmic rays. Occasional brief gaps are typically when RAD was powered off to minimize interference with other activities.
"Our measurements provide crucial information for human missions to Mars," said Dr. Don Hassler, a Southwest Research Institute program director and RAD principal investigator. Hassler is the lead author of "Mars' Surface Radiation Environment Measured with the Mars Science Laboratory's Curiosity Rover," scheduled for publication in the journal Science online on December 9, 2013. "We're continuing to monitor the radiation environment, and seeing the effects of major solar storms on the surface and at different times in the solar cycle will give additional important data. Our measurements also tie into Curiosity's investigations about habitability. The radiation sources that are of concern for human health also affect microbial survival as well as the preservation of organic chemicals."
Two forms of radiation pose potential health risks to astronauts: a chronic low dose of galactic cosmic rays (GCRs) and the possibility of short-term exposures to the solar energetic particles (SEPs) associated with solar flares and coronal mass ejections. The radiation on Mars is much harsher than on Earth for two reasons: Mars lacks a global magnetic field and the Martian atmosphere is much thinner than Earth's, providing little shielding to the surface.
This environmental factor poses a challenge for future human exploration of Mars and is also important in understanding both geological and potential biological evolution on Mars. Both GCRs and SEPs interact with the atmosphere and, if energetic enough, penetrate into the Martian soil, or regolith, where they produce secondary particles that contribute to the complex radiation environment on the Martian surface, which is unlike anything on Earth.
Although the surface of Mimas is heavily cratered, the most striking feature of this small moon is a gigantic crater known as Herschel. It was named after Mimas' discoverer, Sir William Herschel. This crater measures a whopping 80 miles (130 km) across. A central peak in the center of the crater rises to a height of 4 miles, almost as high as Mount Everest on Earth. Since Mimas is only 242 miles (392 km) in diameter, this crater is almost 1/3 of the entire moon's diameter! Astronomers believe that if the object that caused this impact had been any larger, it would have completely destroyed Mimas. This impact was so devastating, in fact, that fracture marks can be found on the opposite side of the moon from the crater. This giant scar gives Mimas the look of a giant eyeball in some photos.
The low density of Mimas indicates that it is composed almost entirely of water ice, very much like Dione and Rhea. Mimas is also covered with small impact craters, but the cratering is not even. Most of the craters average about 25 miles (40 km) in diameter, but craters in the South Polar Region average only 12 miles (20 km). This suggests something may have covered up the larger craters. The fact that none of the other craters are as large as Herschel have led some astronomers to speculate that a previous impact has broken the moon into pieces, which then coalesced to reform the moon into what we see today. Mimas has no detectable atmosphere and no magnetic field.
New analyses indicate that collisions of small particles with large gold nuclei at the Relativistic Heavy Ion Collider may be serving up miniscule servings of hot quark-gluon plasma.
Scientists designed and built the Relativistic Heavy Ion Collider (RHIC) at the U.S. Department of Energy’s Brookhaven National Laboratory to create and study a form of matter that last existed a fraction of a second after the Big Bang, some 13.8 billion years ago. The early-universe matter is created when two beams of gold nuclei traveling close to the speed of light slam into one another. The high-speed particle smashups pack so much energy into such a tiny space that the hundreds of protons and neutrons making up the nuclei “melt” and release their constituent particles—quarks and gluons—so scientists can study these building blocks of matter as they existed at the dawn of time.
Collisions between gold nuclei and deuterons—much smaller particles made of just one proton and one neutron—weren’t supposed to create this superhot subatomic soup known as quark-gluon plasma (QGP). They were designed as a control experiment, to generate data to compare against RHIC’s gold-gold smashups. But new analyses indicate that these smaller particle impacts may be serving up miniscule drops of hot QGP—a finding consistent with similar results from Europe’s Large Hadron Collider (LHC), which can also collide heavy nuclei.
“Considering that the quark-gluon plasma we create in gold-gold collisions at RHIC fills a space that is approximately the size of the nucleus of a single gold atom, the possible hot spots we’re talking about in these deuteron-gold collisions are much, much smaller—and an intriguing surprise.”
Dave Morrison, co-spokesperson for RHIC's PHENIX collaboration
“Considering that the quark-gluon plasma we create in gold-gold collisions at RHIC fills a space that is approximately the size of the nucleus of a single gold atom, the possible hot spots we’re talking about in these deuteron-gold collisions are much, much smaller—and an intriguing surprise,” said Dave Morrison, a physicist at Brookhaven and co-spokesperson for RHIC’s PHENIX collaboration. The collaboration describes their results in two papers just published by Physical Review Letters, one of which is highlighted by the journal.
The findings at RHIC and the LHC have triggered active debate about their interpretation. Said PHENIX co-spokesperson Jamie Nagle of the University of Colorado, “There isn't yet universal agreement about what we’re seeing in these small systems, but if indeed nearly perfect fluid droplets of quark-gluon plasma are being formed, this may be a perfect testing ground for understanding the essential conditions for creating this remarkable state of matter.”
Hens do not have teeth, and humans do not have tails. Research suggests we all have "what it takes" for a tail, and hens, indeed, have the genes that encode for teeth; however, only in very rare situations do these traits manifest themselves as a phenotype. This phenomenon is called atavism—the reappearance of a trait that had been lost during evolution. Our genes do not determine who we are, but with atavism, they can sometimes serve as reminders of our evolutionary past.
Traits that appear or disappear over time are not the result of newly mutated genes encoding defective versions of the proteins associated with teeth or tails, nor are they caused by a loss of existing genes. Instead, a growing body of experimental evidence has shown such traits reflect changes in how, where, and when these genes are expressed.
Even though birds lost teeth as physical structures between 60 and 80 million years ago, several studies have shown that those tissues within birds that would normally produce teeth still retain the potential to do so. For example, in 1821, Geoffrey St. Hilaire was the first scientist to publish the observation that some bird embryos exhibited evidence of tooth formation, but his contemporaries considered his work flawed. Since then, however, many investigators have unearthed molecular evidence that the genes involved in odontogenesis (tooth development) are indeed retained in chickens.
Despite this discovery, no one had yet demonstrated that chickens could develop teeth without external cues. This situation soon changed, however, when researchers Matthew Harris (a graduate student at the time) and John Fallon launched a study involving chickens with a particular kind of autosomal recessive mutation (Harris et al., 2006). These chickens, designated by the abbreviation ta2 for talpid-2, displayed signs reminiscent of early tooth development.
The researchers needed a positive control with which to compare their hens' teeth-that is, a closely related animal in which teeth occur. Typically, the nonmutant or "wild-type" phenotype serves as a control in gene mutation experiments, but this was an exceptional case in that the wild-type chicken doesn't have teeth. Harris and Fallon specifically needed to compare the structures they believed to be teeth in their ta2 mutant chickens with the next best thing—the closest ancestor to the chicken that still has teeth—which in this case was the archosaur, otherwise known as the common crocodile. Therefore, the researchers examined the expression of several biomarkers in wild-type chicken embryos, ta2 mutant embryos, and crocodile embryos. They found that the ta2 mutant oral cavities appeared developmentally closer to those of the crocodiles than to those of their wild-type siblings. These results thus demonstrated that all the genetic pieces to the tooth-building puzzle exist in chickens, but the directions have evolved to tell those pieces to do something different over the last 80 million years.
A few months ago, Andy Rubin, the engineer who spearheaded the development of Android at Google, initiated a new robotics effort at the company. Rubin, who is personally interested in robots, now wants Google to have a major role in making new kinds of robotics happen. Not just robotic cars, but actual real robots. A recent article in the New York Times has revealed more about Google's plans. According to the article, Google is funding a major new robotics group, and that includes acquiring a bunch of robotics startups:
Among the companies are Schaft, a small team of Japanese roboticists who recently left Tokyo University to develop a humanoid robot, and Industrial Perception, a start-up here that has developed computer vision systems and robot arms for loading and unloading trucks. Also acquired were Meka and Redwood Robotics, makers of humanoid robots and robot arms in San Francisco, and Bot & Dolly, a maker of robotic camera systems that were recently used to create special effects in the movie “Gravity.” A related firm, Autofuss, which focuses on advertising and design, and Holomni, a small design firm that makes high-tech wheels, were acquired as well.
The seven companies are capable of creating technologies needed to build a mobile, dexterous robot. Mr. Rubin said he was pursuing additional acquisitions.
Industrial Perception spun out of Willow Garage back in March of 2012; read our Startup Spotlight post on them here.
Meka Robotics builds research robots with series elastic actuators in them; they're probably best known for the M1 humanoid (pictured above in front of the Google logo) and Dreamer, which you can read about here.
And of course, there's Bot & Dolly, which uses robot arms for precise and repeatable camera control, making things way more awesome than "precise and repeatable camera control" probably makes you think of.
Obviously, we're curious about what other acquisitions Rubin is pursuing, and more generally, just what Google is actually working on. Fortunately for us, the Google robotics group will at least initially be based right here in Palo Alto, meaning that I'll get a chance to put my spy drones and ninja outfit to good use.
3D "bioprinting" takes a three-dimensional, biological structure and essentially clones it using a printer.
Louisville researcher Stuart Williams is not talking about a far-off, science-fiction effort when he describes how local scientists will create new, functioning human hearts — using cells and a 3-D printer.
“We think we can do it in 10 years — that we can build, from a patient’s own cells, a total ‘bioficial’ heart,” said Williams, executive and scientific director of the Cardiovascular Innovation Institute, a collaboration between the University of Louisville and the Jewish Heritage Fund for Excellence.
The project is among the most ambitious in the ever-growing field of three-dimensional printing that some experts say could revolutionize medicine.
Known for creating products as diverse as car parts and action figures, 3-D printing is also being used to create models of human bones and organs, medical devices, personalized prosthetics and now, human tissues. Williams describes the process as taking a three-dimensional structure “and essentially cloning it, using a printer.”
“Bioprinting is pretty much done everywhere,” said Dr. Anthony Atala, director of the Wake Forest Institute for Regenerative Medicine in North Carolina, where scientists recently won an award for innovations in bioprinting. “Our ultimate goal is increasing the number of patients who get organs.”
In February 2013, doctors at Weill Cornell Medical College and biomedical engineers at Cornell University in New York announced they had used 3-D printing and injectable gels made of cells to build a facsimile of a human ear that looks and acts like a real one.
And in the case of the baby in Michigan, university officials said the splint was created from a CT scan of the patient’s trachea and bronchus, integrating a computer model with 3-D printing. The baby, who used to stop breathing every day when his collapsed bronchus blocked the flow of air, was off a ventilator three weeks after the surgery, and officials say he hasn’t had breathing trouble since.
Wake Forest scientists, like their peers in Louisville, are working on organs. Officials at Wake Forest say their scientists were the first in the world to engineer a lab-grown organ, and they hope to scale up the process by printing organs with a custom printer. Institute scientists there have also designed a bioprinter to print skin cells onto burn wounds.
So far, Williams said, he knows of no instance where a tissue or organ created through 3-D printing has been implanted in a human. But he said the race is on.
“I think this will have an incredible effect on trauma patients … on the armed forces. You can imagine printing a jaw, printing muscle cells, printing the skin,” he said. “Ultimately I see it being used to print replacement kidneys, to print livers, and to print hearts — and all from your own cells.”
Air flows mostly in a one-way loop through the lungs of monitor lizards -- a breathing method shared by birds, alligators and presumably dinosaurs, according to a new study that may push the evolution of this trait back to 270 million years ago.
Humans and most other animals have a "tidal" breathing pattern: Air flows into the lungs' branching, progressively smaller airways or bronchi until dead-ending at small chambers called alveoli, where oxygen enters the blood and carbon dioxide leaves the blood and enters the lungs. Then the air flows back out the same way.
Birds, on the other hand, have some tidal airflow into and out of air sacs, but their breathing is dominated by one-way airflow in the lung itself. The air flows through the lung in one direction, making a loop before exiting the lung.
A new study conducted by C.G. Farmer, the study's senior author and an associate professor of biology at the University of Utah, found a mostly one-way, looping air flow in African savannah monitor lizards, Varanus exanthematicus -- one of roughly 73 species of monitor lizards -- although there was some tidal airflow in regions of the lungs. That means one-way airflow may have arisen not among the early archosaurs about 250 million years ago, but as early as 270 million years ago among cold-blooded diapsids, which were the common, cold-blooded ancestors of the archosaurs and Lepidosauromorpha, a group of reptiles that today includes lizards, snakes and lizard-like creatures known as tuataras.
One-way airflow may help birds to fly without passing out at high altitudes, where oxygen levels are low. Before the new study, Farmer and others had speculated that the one-way airflow may have helped dinosaurs' ancestors dominate the Earth when atmospheric oxygen levels were low after the Permian-Triassic mass extinction -- the worst in Earth's history -- 251 million years ago.
"But if it evolved in a common ancestor 20 million years earlier, this unidirectional flow would have evolved under very high oxygen levels," Farmer says. "And so were are left with a deeper mystery on the evolutionary origin of one-way airflow."
Australian researchers have found that extreme versions of the cyclical weather pattern El Niño — dubbed 'super El Niños' — will double in frequency under projected global warming scenarios, with repercussions for many countries across the globe.
El Niño is the weather phenomenon responsible for Australia's climate of "droughts and flooding rains". In an El Niño year, a band of warm ocean water rises off the coast of South America, expanding westwards across the Pacific Ocean and displacing colder waters. El Niño in Australia is associated with decreased rainfall.
Some years, such as 1982-83 and 1997-98, the El Niño effect was stronger than usual, with warmer water flowing in an unexpected way.
"These peculiar extreme El Niños were characterised by sea surface temperature anomalies moving eastward along the equatorial Pacific Ocean, with a current reversal," said Dr. Agus Santoso, of the UNSW Climate Change Research Centre, one of the authors of the study.
Crop losses as a result of the 1983 super El Niño were worth US$12 billion in the USA alone.
In a collaborative effort, scientists from the national science agency CSIRO and the Australian Bureau of Meteorology used statistical modelling to uncover how global warming influences the super El Niño.
The team collected weather data to model various warming scenarios ranging in extremity, and used results to predict effects on El Niño cycles originating out of the tropical Pacific Ocean. They found that normal El Niño patterns intensified and occurred more frequently with increased global warming. The study was published in the journal Nature.
NASA's DARPA Robotics Challenge entry is much more than Robonaut with legs: it's a completely new humanoid robot
When teams participating in the DARPA Robotics Challenge (DRC) were announced last year, almost all of them provided reasonably detailed renderings that gave us a good idea of the robots that they were working on.
Valkyrie (officially designated "R5" by NASA) is a 1.9 meter tall, 125 kilogram, 44 degree of freedom, battery-powered humanoid robot. A team from NASA's JSC in Houston, in partnership with the University of Texas and Texas A&M and with funding from the state of Texas itself, built the robot for the DRC, which will hold a preliminary competition later this month. JSC is a Track A team in the DRC; along with five other Track A teams with their own robots, JSC will be competing against Track B and C teams, each one of which will have an ATLAS robot from Boston Dynamics. In addition, Track D teams (which have no DARPA funding) will be entering their own robots.
The challenge created by DARPA involves tasks like walking over uneven terrain, climbing a ladder, using tools, and driving. This means that Valkyrie has to be capable of operating in the same spaces that a person would operate in, under the control of humans who have only minimal training with robots, which is why the robot's design is based on a human form. The overall goal of the DRC is to help drive innovation towards robots that are able to take over from humans directly, without needing any special accommodations. In that context, a human form makes sense because we're humans, and these robots will be doing the jobs that we don't want to be doing because they're too dangerous.
To that end, Valkyrie has seven degree of freedom arms with actuated wrists and hands, each with three fingers and a thumb. It has a head that can tilt and swivel, a waist that can rotate, and six degree of freedom legs complete with feet equipped with six-axis force-torque sensors. Unlike the ATLAS robots, Valkyrie is battery powered and operates without a tether. A removable battery in its backpack is good for about an hour of activity, and a human can swap in a fresh battery for a spent one in a matter of minutes. Also removable are Valkyrie's limbs: in just a few more minutes, a damaged arm can be swapped out for a new one, and the left arm can even be swapped with the right arm, since they're identical in construction. Things are bound to go wrong during the DRC, and the ease with which Valkyrie can be fixed is a potentially significant advantage.
Feeling chilly? Here's cold comfort: You could be in East Antarctica which new data says set a record for soul-crushing cold.
Newly analyzed data from East Antarctica say the remote region has set a record for soul-crushing cold. The record is minus 135.8 Fahrenheit (minus 93.2 Celsius).
A new look at NASA satellite data revealed that Earth set a new record for coldest temperature recorded. It happened in August 2010 when it hit –135.8 F (–93.2 C). Then on July 31 of this year, it came close again: –135.3 F (–92.9 C). The old record had been –128.6 F (–89.2 C).
Ice scientist Ted Scambos at the National Snow and Ice Data Center announced the cold facts at the American Geophysical Union scientific meeting in San Francisco Monday.
"It's more like you'd see on Mars on a nice summer day in the poles," Scambos said, from the American Geophysical Union scientific meeting in San Francisco Monday, where he announced the data. "I'm confident that these pockets are the coldest places on Earth."
However, it won't be in the Guinness Book of World Records because these were satellite measured, not from thermometers, Scambos said.
"Thank God, I don't know how exactly it feels," Scambos said. But he said scientists do routinely make naked –100 F (–73 C) dashes outside in the South Pole as a stunt, so people can survive that temperature for about three minutes.
Most of the time researchers need to breathe through a snorkel that brings air into the coat through a sleeve and warms it up "so you don't inhale by accident" the cold air, Scambos said.
Waleed Abdalati, an ice scientist at the University of Colorado and NASA's former chief scientist, and Scambos said this is likely an unusual random reading in a place that hasn't been measured much before and could have been colder or hotter in the past and we wouldn't know.
"It does speak to the range of conditions on this Earth, some of which we haven't been able to observe," Abdalati said.
Theoretical astrophysicist Abraham Loeb of Harvard University has uploaded a paper he's written to the preprint server arXiv, in which he suggests that conditions shortly after the Big Bang may have been just right for life to appear in some parts of the universe—for just a short time.
Loeb notes that according to theory, 15 million years after the Big Bang, the entire universe would have been warm enough to support life due to the cooling of superheated gases that eventually led to what scientists believe is cosmic microwave background (CMB). Today, it's very cold of course, (2.7 Kelvin), but not long, relatively speaking, after the Big Bang, the temperature would have been closer to 300 Kelvin—more than warm enough to support life if there were a place for it to appear. And that Loeb suggests, might have been possible as well. He notes that it would have been possible for rocky planets to have existed at that time too—in places where matter was exceptionally dense. Because of that, he believes it's possible that all of the pieces necessary for the appearance of life might have been in place in some parts of the universe, for approximately two or three million years—enough time for the initial brewing that could have led to the development of microbes of some sort.
Of course, if it did happen, that life would not have lived long enough (2 to 3 million years) to evolve into anything complex—it would have been snuffed out as the CMB cooled—happening as it would have before stars would have had enough time to form and emit heat of their own. Thus, no evidence would have been left behind, which means Loeb's theory can never be proven. If it could, that might upset another principle regarding the universe—the anthropic principle—which suggests that all of the things that needed to happen in the universe for us to be here today to observe them, exist because we are here to observe them. If life existed and died out before we arrived, it would not have been sophisticated enough to know that it existed, much less observe conditions in the universe that led to its existence. And that would mean the anthropic principle might just be an idea that exists because we have nothing better to explain how and why we are here.
An international team of researchers has zeroed in on a protein that plays a key role in many lung-related ailments, from seasonal coughing and hacking to more serious diseases such as MRSA infections and cystic fibrosis. The finding advances knowledge about this range of illnesses and may point the way to eventually being able to prevent infections such as MRSA.
The key protein is called MUC5B. It’s one of two sugar-rich proteins, with similar molecular structure, that are found in the mucus that normally and helpfully coats airway surfaces in the nose and lung. The other is MUC5AC.
“We knew these two proteins are associated with diseases in which the body produces too much mucus, such as cystic fibrosis, asthma, pulmonary fibrosis and COPD,” said researcher Chris Evans, PhD, an associate professor in the University of Colorado School of Medicine. “We also knew that many patients with asthma or COPD have as much as 95 percent less MUC5B in their lungs than healthy individuals, so we wanted to see if one of these is the bad player in chronic lung diseases.”
The researchers compared mice that lacked one or the other of the proteins. The animals without MUC5B got sick. Those that lacked MUC5AC were fine.
The findings, in a paper co-authored by Evans, other CU faculty members and researchers from several other states as well as Mexico and England, were reported today in the journal Nature.
The finding has interesting implications for anyone with a runny nose. Getting rid of your mucus may make you more comfortable and may help patients with chronic lung diseases,” Evans said. “But if you block it too effectively, this actually could be harmful in the long run. If a treatment gets rid of MUC5B, it may make people more vulnerable to additional infections.”
This chart shows how data from NASA's Wide-field Infrared Survey Explorer, or WISE, has led to revisions in the estimated population of near-Earth asteroids.
Near-Earth asteroids that have already been found are filled in and appear brown. An entire row of asteroid images through the blue outlines shows how many total objects were thought to exist before the NEOWISE survey. The green outlines show the reduced new estimates based on the NEOWISE data.
The infrared-sensing telescope performed the most accurate survey to date of a slice of this population as part of project called NEOWISE. This allowed the science team to make new estimates of the total numbers of the objects in different size categories. NEOWISE observed more than 500 objects larger than 100-meters (330-feet) wide — what can be thought of as medium to large-size asteroids. Near-Earth asteroids smaller than this size range were not studied, and near-Earth comets will be analyzed at a later time. Asteroid sizes are not drawn to scale in the chart.
As the graphic reveals, only a small difference was observed in the estimated total numbers of the largest asteroids — the ones with the potential for global consequences should they impact Earth. For the medium-sized asteroids, which could still destroy a metropolitan area, new estimates predict fewer space rocks than previously thought. Details are listed below.
–For the largest asteroids, larger than 1,000 meters (3,300 feet), NEOWISE data revises the total population down to 981 from a prior estimate of about 1,000. While this is not a dramatic difference, the findings show that NASA has met an initial near-Earth asteroid goal agreed to with Congress in 1998, calling for at least 90 percent of the largest objects to be found. There are an estimated 911 objects of this size range known, which means that NASA has found 93 percent. That leaves roughly 70 of these bodies left to find.
–The NEOWISE data reveals an approximately 44 percent decline in the estimated numbers of medium-sized asteroids, which are defined as those objects between 100 meters and 1,000 meters (330 and 3,300 feet). Estimates now indicate about 19,500, where as 35,000 were thought to exist before.
–The study does not apply to objects smaller than 100 meters (330 feet), but it is estimated that there are more than a million in this size range based on previous studies.
German researchers have developed an innovative approach for measuring blood glucose levels in diabetic patients.
One of the keys to healthful living with Type 1 and Type 2 diabetes is monitoring blood sugar levels to ensure they remain at stable levels.
People can easily and reliably do this at home using electronic devices that read sugar levels in a tiny drop of blood. Now, scientists from the Johann Wolfgang Goethe-University’s Institute for Biophysics and a German industry company have devised a novel, non-invasive way to make monitoring easier.
Using infrared laser light applied on top of the skin, they measure sugar levels in the fluid in and under skin cells to read blood sugar levels. Their approach uses photoacoustic spectroscopy to measure glucose by its mid-infrared absorption of light.
A painless pulse of laser light applied externally to the skin is absorbed by glucose molecules and creates a measurable sound signature that the researchers refer to as ‘the sweet melody of glucose.’ This signal enables researchers to detect glucose in skin fluids in seconds.
“The data showing the skin cell glucose levels at one-hundredth of a millimeter beneath the skin is related to blood glucose levels, but previous attempts to use photoacoustic spectroscopy in this manner have been hampered by distortion related to changes of air pressure, temperature and humidity caused by the contact with living skin,” explained Dr Werner Mäntele, the senior author of a paper published in the journal Review of Scientific Instruments.
A study by S. McMahon and associates (2013) shows that subsurface liquid water maintained by the internal heat of a planet can support an underground biosphere even if the planet is too far from its host star to support life on the planet's surface. The authors introduce a term known as the “subsurface-habitability zone” (SSHZ) to denote the range of distances from a star where a terrestrial planet (i.e. a rocky planet like the Earth) can sustain a subsurface biosphere at any depth below the surface down to a certain maximum habitable depth. This maximum depth depends on numerous factors, but in general, it is the depth where the enormous pressure starts to make the material too compact for life to infiltrate.
Based on the premises that the global average temperature of a terrestrial planet (1) decreases with increasing distance from its host star and (2) increases with depth beneath the planet's surface, the inner (i.e. closer to the host star) and outer (i.e. further from the host star) boundaries of the SSHZ can be determined. The outer edge of the SSHZ is where temperatures are below the freezing point of water at all depths down to the maximum habitable depth. The inner edge of the SSHZ is where the average surface temperature reaches the boiling point of water.
Results from the study show that for a planet with high albedo (high reflectivity), the SSHZ is narrower and closer to the star than for a planet with low albedo (low reflectivity). Furthermore, planets with larger mass have subsurface biospheres that are thinner, shallower and less sensitive to the heat flux from the host star. This is because a more massive planet is expected to have a steeper geothermal gradient whereby the temperature rises more rapidly with increasing depth as compared to a less massive planet. In fact, a 10 Earth-mass planet can support a ~1.5 km thick subsurface biosphere less than ~6 km below its surface even if the planet is at an arbitrarily large distance from its host star.
The possibilities for subsurface biospheres mean that a planet whose surface is too cold for life can still support a deep biosphere that derives its energy and warmth from the planet's own internal heat. An advantage that life in a subsurface biosphere has is that it is well protected from ionizing stellar and cosmic radiation by the overlying rock layers. Since the SSHZ is vastly greater in extent than the traditional habitable zone, cold planets with subsurface biospheres may turn out to be much more common than planets with surface biospheres. Nevertheless, detecting the biosignature of a subsurface biosphere from remote sensing will be more challenging than for a surface biosphere.
McMahon et al., “Circumstellar habitable zones for deep terrestrial biospheres”, Planetary and Space Science 85 (2013) 312-318.
Scientists at the Stanford University School of Medicine have determined the precise anatomical coordinates of a brain “hot spot,” measuring only about one-fifth of an inch across, that is preferentially activated when people view the ordinary numerals we learn early on in elementary school, like “6” or “38.”
Activity in this spot relative to neighboring sites drops off substantially when people are presented with numbers that are spelled out (“one” instead of “1”), homophones (“won” instead of “1”) or “false fonts,” in which a numeral or letter has been altered.
“This is the first-ever study to show the existence of a cluster of nerve cells in the human brain that specializes in processing numerals,” said Josef Parvizi, MD, PhD, associate professor of neurology and neurological sciences and director of Stanford’s Human Intracranial Cognitive Electrophysiology Program. “In this small nerve-cell population, we saw a much bigger response to numerals than to very similar-looking, similar-sounding and similar-meaning symbols.
“It’s a dramatic demonstration of our brain circuitry’s capacity to change in response to education,” he added. “No one is born with the innate ability to recognize numerals.”The finding pries open the door to further discoveries delineating the flow of math-focused information processing in the brain. It also could have direct clinical ramifications for patients with dyslexia for numbers and with dyscalculia: the inability to process numerical information.
Interestingly, said Parvizi, that numeral-processing nerve-cell cluster is parked within a larger group of neurons that is activated by visual symbols that have lines with angles and curves. “These neuronal populations showed a preference for numerals compared with words that denote or sound like those numerals,” he said. “But in many cases, these sites actually responded strongly to scrambled letters or scrambled numerals. Still, within this larger pool of generic neurons, the ‘visual numeral area’ preferred real numerals to the false fonts and to same-meaning or similar-sounding words.”
It seems, Parvizi said, that “evolution has designed this brain region to detect visual stimuli such as lines intersecting at various angles — the kind of intersections a monkey has to make sense of quickly when swinging from branch to branch in a dense jungle.” The adaptation of one part of this region in service of numeracy is a beautiful intersection of culture and neurobiology, he said.
Having nailed down a specifically numeral-oriented spot in the brain, Parvizi’s lab is looking to use it in tracing the pathways described by the brain’s number-processing circuitry. “Neurons that fire together wire together,” said Shum. “We want to see how this particular area connects with and communicates with other parts of the brain.”
Scientists have found evidence of an ancient freshwater lake on Mars well suited to support microbial life, the researchers said. The lake, located inside Gale Crater where the rover landed in August 2012, likely covered an area 31 miles long and 3 miles wide, though its size varied over time. Analysis of sedimentary deposits gathered by NASA's Mars rover Curiosity shows the lake existed for at least tens of thousands of years, and possibly longer, geologist John Grotzinger, with the California Institute of Technology in Pasadena, told reporters at the American Geophysical Union conference in San Francisco.
"We've come to appreciate that is a habitable system of environments that includes the lake, the associated streams and, at times when the lake was dry, the groundwater," he said. Analysis of clays drilled out from two rock samples in the area known as Yellowknife Bay show the freshwater lake existed at a time when other parts of Mars were dried up or dotted with shallow, acidic, salty pools ill-suited for life.
In contrast, the lake in Gale Crater could have supported a simple class of rock-eating microbes, known as chemolithoautotrophs, which on Earth are commonly found in caves and hydrothermal vents on the ocean floor, Grotzinger said. Scientists also reported that the clays, which form in the presence of water, were younger than expected, a finding that expands the window of time for when Mars may have been suited for life. The planet's surface is riddled with geologic features carved by water, such as channels, dried up riverbeds, lake deltas and other sedimentary deposits.
Scientists will continue to look for rocks that may have higher concentrations of organics or better chemical conditions for their preservation, Grotzinger said. "A key hurdle that we need to overcome is understanding how those organics may have been preserved over time, from the time they entered the rock to the time that we actually detect them," said Curiosity scientist Jennifer Eigenbrode with NASA's Goddard Space Flight Center in Greenbelt, Maryland.