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Trail of Tools Reveals Modern Humans' Path Out of Africa

Trail of Tools Reveals Modern Humans' Path Out of Africa | Amazing Science |

Where did our species come from, and how did we get from there to everywhere? A 55,000-year-old partial skull found in Manot Cave in western Galilee in January 2015 suggests that modern humans were in the Levant around the same time as Neanderthals.

Now, a pair of American archaeologists claim to have uncovered the route those early Homo sapiens took on their way to populating the planet. By following the broken trail of stone tools that modern humans left behind like bread crumbs marking their path, researchers propose that our ancestors took a circuitous path through Arabia, pausing there for some 50,000 years when it was a green oasis. Then they journeyed on to the Middle East, where they first encountered Neanderthals.

Stylistic and manufacturing similarities, the archaeologists say, connect the dots between tools made first in the Nile Valley of Egypt, then in the Arabian Peninsula, and, finally, in Israel. Those tools became progressively smaller and more sophisticated, similar to the evolution of mobile phones today.

"Archaeologists have always focused so much on 'out of Africa and into the Middle East' that we've missed an entire chapter of the human expansion in Arabia," says archaeologist Jeffrey Rose of the Ronin Institute, based in New Jersey, co-author of a new report published this month in Quartär.

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Fever alarm armband: A wearable, printable, temperature sensor

Fever alarm armband: A wearable, printable, temperature sensor | Amazing Science |
University of Tokyo researchers have developed a "fever alarm armband," a flexible, self-powered wearable device that sounds an alarm in case of high body temperature. This armband will be presented at the 2015 IEEE International Solid State Circuits Conference, San Francisco, on 22-26 February, 2015. The flexible organic components developed for this device are well-suited to wearable devices that continuously monitor vital signs including temperature and heart rate for applications in healthcare settings.

The new device developed by research groups lead by Professor Takayasu Sakurai at the Institute of Industrial Science and Professor Takao Someya at the Graduate School of Engineering combines a flexible amorphous silicon solar panel, piezoelectric speaker, temperature sensor, and power supply circuit created with organic components in a single flexible, wearable package.

Constant monitoring of health indicators such as heart rate and body temperature is the focus of intense interest in the fields of infant, elderly and patient care. Sensors for such applications need to be flexible and wireless for patient comfort, maintenance-free and not requiring external energy supply, and cheap enough to permit disposable use to ensure hygiene. Conventional sensors based on rigid components are unable to meet these requirements, so the researchers have developed a flexible solution that incorporates organic components that can be printed by an inkjet printer on a polymeric film.

The fever alarm armband incorporates several first-ever achievements. It is the first organic circuit able to produce a sound output, and the first to incorporate an organic power supply circuit. The former enables the device to provide audible information when the flexible thermal sensor detects a pre-set value within the ranges of 36.5 ºC to 38.5 ºC, while the latter increases the range of operational illumination by 7.3 times in indoor lighting conditions.

"Our fever alarm armband demonstrates that it is possible to produce flexible, disposable devices that can greatly enhance the amount of information available to carers in healthcare settings," says Professor Someya. "We have demonstrated the technology with a temperature sensor and fever alarm, but the system could also be adapted to provide audible feedback on body temperature, or combined with other sensors to register wetness, pressure or heart rate."
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Hidden in Plain Sight: Amazonian Bird Chick Mimics Toxic Caterpillar to Avoid Being Eaten

Hidden in Plain Sight: Amazonian Bird Chick Mimics Toxic Caterpillar to Avoid Being Eaten | Amazing Science |
In a study published in the January 2015 issue of The American Naturalist (, Gustavo A. Londoño, Duván Garcia, and Manuel Sánchez Martínez report a novel nesting strategy observed in a tropical lowland bird that inhabits an area with very high losses to nest predators.
How can tropical birds cope with the high rates of nest predation that are typical in most tropical habitats? Are there nesting strategies that allow tropical birds to escape predators such as birds, mammals, and snakes that regularly eat eggs and nestlings?
During the fall of 2012, while working on a long-term avian ecological study, the researchers discovered the second nest ever described for the cinereous mourner (Laniocera hypopyrra) at Pantiacolla Lodge in the upper Madre de Dios River in southeastern Peru. They observed that upon hatching, the chicks had downy feathers with long orange barbs with white tips, which was very different from any other nestling they had observed in the area. The peculiar downy feathers attracted their attention, but the nestling behavior provided a more important cue. While researchers were collecting morphological measurements, the nestling started moving its head very slowly from side to side in a way typical of many hairy caterpillars. While working in the area, the investigators found a poisonous caterpillar with similar size and hair coloration as the nestling. Therefore, the researchers suggest that this is an example of Batesian mimicry in which the nestling tricks predators into thinking that it is a toxic, spiny caterpillar rather than a highly edible nestling.
This remarkable adaptation may well have evolved to decrease nest predation probability, increasing nesting success in this species. Examples of Batesian mimicry are very rare in vertebrates.
LEONARDO WILD's curator insight, February 25, 2015 8:01 AM

Biomimicry is not an anthropocentric behavior.

Sue Gaardboe's curator insight, February 25, 2015 8:45 PM

Wonderful to have an example of evolutionary camouflage to share with students. 

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How Wearable Startups Can Win Big In The Medical Industry

How Wearable Startups Can Win Big In The Medical Industry | Amazing Science |

As attention shines down on fitness trackers and smart watches, one of the biggest opportunities for wearable devices remains shadowed in the corner. Turning a product into a business is actually quite simple — get paid. The time is now forwearable companies to build corporate partnerships into their business model.

Existing medical companies need to keep proving that their products offer reimbursable value even after they complete clinical trials and are FDA approved. Wearables enable them to collect “real world evidence” as people go about their daily lives. Some companies are even expanding in population health management and healthcare services to ensure their products deliver on their promise. One case of this is Medtronic, which has expanded beyond cardiovascular devices into tele-health and remote patient monitoring services. Its Cardiocom business unit uses a number of wired products to provide telemedicine. Imagine what its platform would look like if it had 24/7 data from patients on key physiologic measures.

The right partner can also help startups by validating products in clinical trials, which is appealing to an investor. For example, pharma company UCB signed a deal with electronics company MC10 to test its “BioStamp” in clinical trials for new neurological therapies.

Selling to the medical community may seem like a daunting proposition, but I believe this is where the big opportunities lie for medical wearable startups. For one thing, consumer-focused wearables aren’t living up to their promise. Research from Endeavor Partners found that one-third of consumers abandon their wearables after just a few months. Clearly the appeal of tracking steps is not enough to keep people interested in these devices.

Furthermore, focusing wearable device development on the consumer market (specifically young, wealthy, and tech-savvy early adopters) means that, in the words of J.C. Herz, “wearables are totally failing the people who need them most” — the old, the chronically ill, and the poor. Medical wearables are one of the rare and exciting areas where technology canhave a marked, positive impact on people’s lives while also making big money at the same time. I can’t wait to see more entrepreneurs taking on these challenges.

Christopher Rudolf's curator insight, February 24, 2015 8:42 AM

Really great article on the way med devices can be built to be successful for patient outcomes and also commercially.

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Mice embryos grow a bigger brain with human DNA

Mice embryos grow a bigger brain with human DNA | Amazing Science |

The size of the human brain expanded dramatically during the course of evolution, imparting us with unique capabilities to use abstract language and do complex math. But how did the human brain get larger than that of our closest living relative, the chimpanzee, if almost all of our genes are the same?

Duke scientists have shown that it's possible to pick out key changes in the genetic code between chimpanzees and humans and then visualize their respective contributions to early brain development by using mouse embryos. The team found that humans are equipped with tiny differences in a particular regulator of gene activity, dubbed HARE5, that when introduced into a mouse embryo, led to a 12% bigger brain than in the embryos treated with the HARE5 sequence from chimpanzees.

The findings, appearing online Feb. 19, 2015, in Current Biology, may lend insight into not only what makes the human brain special but also why people get some diseases, such as autism and Alzheimer's disease, whereas chimpanzees don't.

"I think we've just scratched the surface, in terms of what we can gain from this sort of study," said Debra Silver, an assistant professor of molecular genetics and microbiology in the Duke University Medical School. "There are some other really compelling candidates that we found that may also lead us to a better understanding of the uniqueness of the human brain."

Every genome contains many thousands of short bits of DNA called 'enhancers,' whose role is to control the activity of genes. Some of these are unique to humans. Some are active in specific tissues. But none of the human-specific enhancers previously had been shown to influence brain anatomy directly.

In the new study, researchers mined databases of genomic data from humans and chimpanzees, to find enhancers expressed primarily in the brain tissue and early in development. They prioritized enhancers that differed markedly between the two species. The group's initial screen turned up 106 candidates, six of them near genes that are believed to be involved in brain development. The group named these 'human-accelerated regulatory enhancers,' HARE1 through HARE6.

The strongest candidate was HARE5 for its chromosomal location near a gene called Frizzled 8, which is part of a well-known molecular pathway implicated in brain development and disease. The group decided to focus on HARE5 and then showed that it was likely to be an enhancer for Frizzled8 because the two DNA sequences made physical contact in brain tissue.

The human HARE5 and the chimpanzee HARE5 sequences differ by only 16 letters in their genetic code. Yet, in mouse embryos the researchers found that the human enhancer was active earlier in development and more active in general than the chimpanzee enhancer.

"What's really exciting about this was that the activity differences were detected at a critical time in brain development: when neural progenitor cells are proliferating and expanding in number, just prior to producing neurons," Silver said.

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New ‘in silico’ method of predicting effectiveness of cognitive enhancers

New ‘in silico’ method of predicting effectiveness of cognitive enhancers | Amazing Science |

The Biogerontology Research Foundation (BGRF) has used gene expression data to evaluate activated or suppressed signaling pathways in tissues or neurons of the mouse brain that has been cognitively enhanced with nootropic drugs.

Currently used cognitive enhancers are those that are widely available, rather than optimal for the user, the researchers note. These include drugs typically prescribed for treatment of ADHD (e.g., methylphenidate) and sleep disturbances such as narcolepsy (modafinil). The researchers want to quantify the effects with objective measures and thus predict the efficacy of the many drugs that may enhance various aspects of cognition — before costly preclinical studies and clinical trials are undertaken.

The research, published in open-access Frontiers in Systems Neuroscience, uses an algorithm that maps expression data onto signaling pathways. The collective pathways and their activation form a “signaling pathway cloud” — a biological fingerprint of cognitive enhancement. Drugs can then be screened and ranked based on their ability to minimize, mimic, or exaggerate pathway activation or suppression within that cloud.

“Our current work in predicting the efficacy of drugs and drug combinations in treating and preventing some of the most age-related diseases, suggests that some likely geroprotectors may also enhance cognitive function, said Alex Zhavoronkov, PhD, director of the BGRF. “We are actively seeking academic and industry collaborators for this exciting neuroscience project.”

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Crunch time for Mars One to avoid a two-year delay

Crunch time for Mars One to avoid a two-year delay | Amazing Science |

Mars One, the Dutch firm hoping to colonise the Red Planet, has just a few months to decide whether it will launch its first unmanned mission to Mars in 2018. If it misses the deadline, the entire high-risk enterprise will be delayed another two years. While national space agencies think manned missions to Mars are something for the distant future, Mars One says it can establish a permanent colony on the planet by the mid-2020s, funded by turning the whole thing into a reality TV show and selling the media rights.

In 2013 the firm announced a partnership with aerospace firm Lockheed Martin to build an unmanned Mars lander based on an old NASA probe, Phoenix, that would extract water from the surface and test solar panel technology. It also signed a separate contract with UK firm Surrey Satellite Technology (SSTL) to build a communications satellite to relay live video from the lander.

But yesterday, SpaceNews reported that work on these two missions had been suspended – a claim Mars One CEO Bas Lansdorp denies. "We're currently reviewing the results of the work our suppliers did and are preparing for the next contracts, so we're simply in between contracts," he says. "The 2018 robotic mission is still the very very highest priority for Mars One." But meeting the 2018 launch date will be tricky, he admits. "If we cannot make this deadline we are always flexible in moving another two years," he says. "That's a decision that we will have to make before the summer." The Mars One timeline has already slipped, as initial plans called for a communications satellite in 2014.

Mars One recently announced it has narrowed the pool of applicants down to 100 astronaut candidates who will start training for what will be a one-way trip, assuming it gets off the ground. Lansdorp says the firm will start building a simulation of the astronauts' future Mars base in the Netherlands later this year. "We are in negotiation with the construction company, but the actual construction hasn't started." The plan to sell the TV rights is on shaky ground, too. Lansdorp says a deal with media company Endemol, which produced Big Brother, has fallen through, and it will instead work with an as-yet unnamed company to produce a documentary series.

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Development of an Epigenome Browser to Help Understanding the Functional Complexity of the Genome

Development of an Epigenome Browser to Help Understanding the Functional Complexity of the Genome | Amazing Science |

Advances in next-generation sequencing platforms have reshaped the landscape of functional genomic and epigenomic research as well as human genetics studies. Annotation of noncoding regions in the genome with genomic and epigenomic data has facilitated the generation of new, testable hypotheses regarding the functional consequences of genetic variants associated with human complex traits1. Large consortia, such as the US National Institutes of Health (NIH) Roadmap Epigenomics Consortium3 and ENCODE4, have generated tens of thousands of sequencing-based genome-wide data sets, creating a useful resource for the scientific community5. The WashU Epigenome Browser68 continues to provide a platform for investigators to effectively engage with this resource in the context of analyzing their own data.

The newly developed Roadmap Epigenome Browser ( is based on the WashU Epigenome Browser and integrates data from both the NIH Roadmap Epigenomics Consortium and ENCODE in a visualization and bioinformatics tool that enables researchers to explore the tissue-specific regulatory roles of genetic variants in the context of disease. The browser takes advantage of the over 10,000 epigenomic data sets it currently hosts, including 346 'complete epigenomes', defined as tissues and cell types for which we have collected a complete set of DNA methylation, histone modification, open chromatin and other genomic data sets9.

Data from both the NIH Roadmap Epigenomics and ENCODE resources are seamlessly integrated in the browser using a new Data Hub Cluster framework. Investigators can specify any number of single nucleotide polymorphism (SNP)-associated regions and any type of epigenomic data, for which the browser automatically creates virtual data hubs through a shared hierarchical metadata annotation, retrieves the data and performs real-time clustering analysis. Investigators interact with the browser to determine the tissue specificity of the epigenetic state encompassing genetic variants in physiologically or pathogenically relevant cell types from normal or diseased samples.

The epigenomic annotation of two noncoding SNPs can be identified from genome-wide association studies of people with multiple sclerosis10, by clustering the histone H3K4me1 profile of SNP-harboring regions and RNA-seq signal of their closest genes across multiple primary tissues and cellsThus, reference epigenomes provide important clues into the functional relevance of these genetic variants in the context of the pathophysiology of multiple sclerosis, including inflammation11.

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Drug-resistant malaria 'huge threat'

Drug-resistant malaria 'huge threat' | Amazing Science |

Resistance to the drug that has saved millions of lives from malaria has been detected over a wider area than previously thought. Drug-resistant malaria is spreading in South East Asia, and has now reached the Cambodia-Thailand border, according to a study. "Radical action" is needed to prevent further spread of malaria parasites resistant to key drugs, say scientists. The ability of the malaria parasite to shrug off the effects of artemisinin has been spreading since it emerged in South East Asia.

Tests, published in Lancet Infectious Diseases, now show this resistance on the verge of entering India. Experts said the development was "alarming" and an "enormous threat". Deaths from malaria have nearly halved since 2000, and the infection now kills about 584,000 people each year. Blood samples from 940 people with malaria from 55 sites across Myanmar showed this resistance was widespread across the country.

Chloroquine probably saved hundreds of millions of lives, but resistance was discovered in 1957 around the border between Cambodia and Thailand. Resistance spread around the world and reached Africa 17 years later. There is no evidence of artemisinin resistance in Africa yet, although there is concern that history is about to repeat itself with deadly consequences.

South East Asia has been implicated in the rise of resistance to both chloroquine and artemisinin. The main explanation is that lower levels of natural malaria immunity exist in the region than in Africa. With no background resistance, the drugs have to do all the work in infected patients in South East Asia. But there are far more cases of malaria in Africa, and repeat infection is common so people there develop some immunity. It means the natural immune system and the drug share the load of fighting off malaria. This makes South East Asia a riper region for the parasite to develop resistance.

Prof Philippe Guerin, the director of the Worldwide Antimalarial Resistance Network, said: "This study highlights that the pace at which artemisinin resistance is spreading or emerging is alarming. "We need a more vigorous international effort to address this issue in border regions."

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Indo-European languages emerged roughly 6,500 years ago on Russian steppes, new research suggests

Indo-European languages emerged roughly 6,500 years ago on Russian steppes, new research suggests | Amazing Science |

Linguists have long agreed that languages from English to Greek to Hindi, known as 'Indo-European languages', are part of a language family which first emerged from a common ancestor spoken thousands of years ago. Now, a new study gives us more information on when and where it was most likely used. Using data from over 150 languages, linguists at the University of California, Berkeley provide evidence that this ancestor language originated 5,500 - 6,500 years ago, on the Pontic-Caspian steppe stretching from Moldova and Ukraine to Russia and western Kazakhstan.

"Ancestry-constrained phylogenetic analysis supports the Indo-European steppe hypothesis", by Will Chang, Chundra Cathcart, David Hall and Andrew Garrett, will appear in the March issue of the academic journal LanguageThis article is available on the LSA website.

The article provides new support for the "steppe hypothesis" or "Kurgan hypothesis", which proposes that Indo-European languages first spread with cultural developments in animal husbandry around 4500 - 3500 BCE. An alternate theory proposes that they spread much earlier, around 7500 - 6000 BCE, in Anatolia in modern-day Turkey.

Chang et al. examined over 200 sets of words from living and historical Indo-European languages; after determining how quickly these words changed over time through statistical modeling, they concluded that the rate of change indicated that the languages which first used these words began to diverge approximately 6,500 years ago, in accordance with the steppe hypothesis.

This is one of the first quantitatively-based academic papers in support of the steppe hypothesis, and the first to use a model with "ancestry constraints" which more directly incorporate previously discovered relationships between languages. Discussion of prior studies in favor of and against the steppe hypothesis can be found in the paper.

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3-D engineered bone marrow makes functioning platelets

3-D engineered bone marrow makes functioning platelets | Amazing Science |

A team led by researchers at Tufts University School of Engineering and the University of Pavia has reported development of the first three-dimensional tissue system that reproduces the complex structure and physiology of human bone marrow and successfully generates functional human platelets. Using a biomaterial matrix of porous silk, the new system is capable of producing platelets for future clinical use and also provides a laboratory tissue system to advance study of blood platelet diseases."

There are many diseases where platelet production or function is impaired," says Alessandra Balduini, M.D., research associate professor in the Department of Biomedical Engineering at Tufts, associate professor at the Department of Molecular Medicine at the University of Pavia and co-corresponding author on the paper. "New insight into the formation of platelets would have a major impact on patients and healthcare. In this tissue system, we can culture patient-derived megakaryocytes -- the bone marrow cells that make platelets -- and also endothelial cells, which are found in bone marrow and promote platelet production, to design patient-specific drug administration regimes."

The new system can also provide an in vitro laboratory tissue system with which to study mechanisms of blood disease and to predict efficacy of new drugs--providing a more precise and less costly alternative to in vivo animal models.

"The need for platelet production systems to treat patients with related diseases is significant. This patient-specific system could provide new insight and options for clinical treatments," says David Kaplan, Ph.D., chair of biomedical engineering and Stern Family professor at Tufts and co-corresponding author. "Further the platelets can be generated on demand, avoiding the complications of storage problems, and in greater quantities and with better quality and control in terms of morphology and function."

The work is pre-published online in the journal Blood prior to print publication ("Programmable 3D silk bone marrow niche for platelet generation ex vivo and modeling of megakaryopoiesis pathologies").

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New self-healing nanogel for drug delivery

New self-healing nanogel for drug delivery | Amazing Science |
Self-healing gel can be injected into the body and act as a long-term drug depot.

Scientists are interested in using gels to deliver drugs because they can be molded into specific shapes and designed to release their payload over a specified time period. However, current versions aren’t always practical because must be implanted surgically.

To help overcome that obstacle, MIT chemical engineers have designed a new type of self-healing hydrogel that could be injected through a syringe. Such gels, which can carry one or two drugs at a time, could be useful for treating cancer, macular degeneration, or heart disease, among other diseases, the researchers say.

The new gel consists of a mesh network made of two components: nanoparticles made of polymers entwined within strands of another polymer, such as cellulose. “Now you have a gel that can change shape when you apply stress to it, and then, importantly, it can re-heal when you relax those forces. That allows you to squeeze it through a syringe or a needle and get it into the body without surgery,” says Mark Tibbitt, a postdoc at MIT’s Koch Institute for Integrative Cancer Research and one of the lead authors of a paper describing the gel in Nature Communications on Feb. 19.

Scientists have previously constructed hydrogels for biomedical uses by forming irreversible chemical linkages between polymers. These gels, used to make soft contact lenses, among other applications, are tough and sturdy, but once they are formed their shape cannot easily be altered. The MIT team set out to create a gel that could survive strong mechanical forces, known as shear forces, and then reform itself. Other researchers have created such gels by engineering proteins that self-assemble into hydrogels, but this approach requires complex biochemical processes. The MIT team wanted to design something simpler. “We’re working with really simple materials,” Tibbitt says. “They don’t require any advanced chemical functionalization.”

The MIT approach relies on a combination of two readily available components. One is a type of nanoparticle formed of PEG-PLA copolymers, first developed in Langer’s lab decades ago and now commonly used to package and deliver drugs. To form a hydrogel, the researchers mixed these particles with a polymer — in this case, cellulose.

Each polymer chain forms weak bonds with many nanoparticles, producing a loosely woven lattice of polymers and nanoparticles. Because each attachment point is fairly weak, the bonds break apart under mechanical stress, such as when injected through a syringe. When the shear forces are over, the polymers and nanoparticles form new attachments with different partners, healing the gel.

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Human sex redefined: The idea of two sexes is simplistic. Biologists now think there is a wider spectrum than that

Human sex redefined: The idea of two sexes is simplistic. Biologists now think there is a wider spectrum than that | Amazing Science |

As a clinical geneticist, Paul James is accustomed to discussing some of the most delicate issues with his patients. But in early 2010, he found himself having a particularly awkward conversation about sex.

A 46-year-old pregnant woman had visited his clinic at the Royal Melbourne Hospital in Australia to hear the results of an amniocentesis test to screen her baby's chromosomes for abnormalities. The baby was fine — but follow-up tests had revealed something astonishing about the mother. Her body was built of cells from two individuals, probably from twin embryos that had merged in her own mother's womb. And there was more. One set of cells carried two X chromosomes, the complement that typically makes a person female; the other had an X and a Y. Halfway through her fifth decade and pregnant with her third child, the woman learned for the first time that a large part of her body was chromosomally male1. “That's kind of science-fiction material for someone who just came in for an amniocentesis,” says James.

Sex can be much more complicated than it at first seems. According to the simple scenario, the presence or absence of a Y chromosome is what counts: with it, you are male, and without it, you are female. But doctors have long known that some people straddle the boundary — their sex chromosomes say one thing, but their gonads (ovaries or testes) or sexual anatomy say another. Parents of children with these kinds of conditions — known as intersex conditions, or differences or disorders of sex development (DSDs) — often face difficult decisions about whether to bring up their child as a boy or a girl. Some researchers now say that as many as 1 person in 100 has some form of DSD2.

When genetics is taken into consideration, the boundary between the sexes becomes even blurrier. Scientists have identified many of the genes involved in the main forms of DSD, and have uncovered variations in these genes that have subtle effects on a person's anatomical or physiological sex. What's more, new technologies in DNA sequencing and cell biology are revealing that almost everyone is, to varying degrees, a patchwork of genetically distinct cells, some with a sex that might not match that of the rest of their body. Some studies even suggest that the sex of each cell drives its behaviour, through a complicated network of molecular interactions. “I think there's much greater diversity within male or female, and there is certainly an area of overlap where some people can't easily define themselves within the binary structure,” says John Achermann, who studies sex development and endocrinology at University College London's Institute of Child Health.

These discoveries do not sit well in a world in which sex is still defined in binary terms. Few legal systems allow for any ambiguity in biological sex, and a person's legal rights and social status can be heavily influenced by whether their birth certificate says male or female.

“The main problem with a strong dichotomy is that there are intermediate cases that push the limits and ask us to figure out exactly where the dividing line is between males and females,” says Arthur Arnold at the University of California, Los Angeles, who studies biological sex differences. “And that's often a very difficult problem, because sex can be defined a number of ways.”

That the two sexes are physically different is obvious, but at the start of life, it is not. Five weeks into development, a human embryo has the potential to form both male and female anatomy. Next to the developing kidneys, two bulges known as the gonadal ridges emerge alongside two pairs of ducts, one of which can form the uterus and Fallopian tubes, and the other the male internal genital plumbing: the epididymes, vas deferentia and seminal vesicles. At six weeks, the gonad switches on the developmental pathway to become an ovary or a testis. If a testis develops, it secretes testosterone, which supports the development of the male ducts. It also makes other hormones that force the presumptive uterus and Fallopian tubes to shrink away. If the gonad becomes an ovary, it makes oestrogen, and the lack of testosterone causes the male plumbing to wither. The sex hormones also dictate the development of the external genitalia, and they come into play once more at puberty, triggering the development of secondary sexual characteristics such as breasts or facial hair.

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Three Men have their hands amputated and replaced with bionic ones

Three Men have their hands amputated and replaced with bionic ones | Amazing Science |

Bionic hands are go. Three men with serious nerve damage had their hands amputated and replaced by prosthetic ones that they can control with their minds.

The procedure, dubbed "bionic reconstruction", was carried out by Oskar Aszmann at the Medical University of Vienna, Austria.

The men had all suffered accidents which damaged the brachial plexus – the bundle of nerve fibers that runs from the spine to the hand. Despite attempted repairs to those nerves, the arm and hand remained paralyzed.

"But still there are some nerve fibers present," says Aszmann. "The injury is so massive that there are only a few. This is just not enough to make the hand alive. They will never drive a hand, but they might drive a prosthetic hand."

This approach works because the prosthetic hands come with their own power source. Aszmann's patients plug their hands in to charge every night. Relying on electricity from the grid to power the hand means all the muscles and nerves need do is send the right signals to a prosthetic.

First they practized activating the muscle using an armband of sensors that picked up on the electrical activity. Then they moved on to controlling a virtual arm. Finally, Aszmann amputated their hands, and replaced them with a standard prosthesis under the control of the muscle and sensors.

"I was impressed and first struck with the surgical innovation," says Dustin Tyler of the Louis Stokes Veterans Affairs Medical Center in Cleveland, Ohio. "There's something very personal about having a hand; most people will go to great lengths to recover one, even if it's not very functional. It's interesting that people are opting for this."

While Aszmann's approach uses a grafted muscle to relay signals from the brain to a prosthesis, others are taking a more direct route, reading brain waves directly and using them to control the hand. A team at the University of Pittsburgh, Pennsylvania, has used a brain implant to allow a paralysed woman to control a robotic arm using her thoughts alone.

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Scientists Take First X-ray Portraits of Living Bacteria

Scientists Take First X-ray Portraits of Living Bacteria | Amazing Science |

Researchers working at the Department of Energy’s SLAC National Accelerator Laboratory have captured the first X-ray portraits of living bacteria. This milestone, reported in the Feb. 11 issue of Nature Communications, is a first step toward possible X-ray explorations of the molecular machinery at work in viral infections, cell division, photosynthesis and other processes that are important to biology, human health and our environment. The experiment took place at SLAC’s Linac Coherent Light Source (LCLS) X-ray laser, a DOE Office of Science User Facility.

“We have developed a unique way to rapidly explore, sort and analyze samples, with the possibility of reaching higher resolutions than other study methods,” said Janos Hajdu, a professor of biophysics at Uppsala University in Sweden, which led the research. “This could eventually be a complete game-changer.”

The experiment focused on cyanobacteria, or blue-green algae, an abundant form of bacteria that transformed Earth’s atmosphere 2.5 billion years ago by releasing breathable oxygen, making possible new forms of life that are dominant today. Cyanobacteria play a key role in the planet’s oxygen, carbon and nitrogen cycles.

Researchers sprayed living cyanobacteria in a thin stream of humid gas through a gun-like device. The cyanobacteria were alive and intact when they flew into the ultrabright, rapid-fire LCLS X-ray pulses, producing diffraction patterns recorded by detectors. The diffraction patterns preserved details of the living cyanobacteria that were compiled to reconstruct 2-D images. Researchers said it should be possible to produce 3-D images of some samples using the same technique.

The technique works with live bacteria and requires no special treatment of the samples before imaging. Other high-resolution imaging methods may require special dyes to increase the contrast in images, or work only on dead or frozen samples.  The technique can capture about 100 images per second, amassing many millions of high-resolution X-ray images in a single day. This speed allows sorting and analysis of the inner structure and activity of biological particles on a massive scale, which could be arranged to show the chronological steps of a range of cellular activities.

In this way, the technique merges biology and big data, said Tomas Ekeberg, a biophysicist at Uppsala University. “You can study the full cycle of cellular processes, with each X-ray pulse providing a snapshot of the process you want to study,” he said.

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Bacteria food network found: Some bacteria form nanotubular structures between single cells to exchange nutrients

Bacteria food network found: Some bacteria form nanotubular structures between single cells to exchange nutrients | Amazing Science |

It is well-known that bacteria can support each others’ growth and exchange nutrients. Scientists at the Max Planck Institute for Chemical Ecology in Jena, Germany, and their colleagues at the universities of Jena, Kaiserslautern, and Heidelberg, however, have now discovered a new way of how bacteria can achieve this nutritional exchange. They found that some bacteria can form nanotubular structures between single cells that enable a direct exchange of nutrients.

Bacteria usually live in species-rich communities and frequently exchange nutrients and other metabolites. Until now, it was unclear whether microorganisms exchange metabolites exclusively by releasing them into the surrounding environment or whether they also use direct connections between cells for this purpose. Scientists from the Research Group Experimental Ecology and Evolution at the Max Planck Institute for Chemical Ecology in Jena, Germany addressed this question using the soil bacterium Acinetobacter baylyi and the gut microbe Escherichia coli. By experimentally deleting bacterial genes from the genome of both species, the scientists generated mutants that were no longer able to produce certain amino acids, yet produced increased amounts of others.

In co-culture, both bacterial strains were able to cross-feed each other, thereby compensating the experimentally induced deficiencies. However, separating the two bacterial strains with a filter that allowed free passage of amino acids, yet prevented a direct contact between cells, abolished growth of both strains. “This experiment showed that a direct contact between cells was required for the nutrient exchange to occur,” explains Samay Pande, who recently obtained his PhD at the Max Planck Institute in Jena on this research project and now started a postdoc at the ETH Zürich.

Observing the co-culture under the electron microscope revealed structures that formed between bacterial strains, which functioned as nanotubes and enabled the exchange of nutrients between cells. Especially remarkable, however, was the fact that only the gut microbe Escherichia coli was capable of forming these structures and connecting to Acinetobacter baylyi or other E. coli cells. “The major difference between both species is certainly that E. coli is able to actively move in liquid media, whereas A. baylyi is immotile. It may thus be possible that swimming is required for E. coli to find suitable partners and connect to them via nanotubes,” explains Christian Kost, head of the Research Group Experimental Ecology and Evolution, which is funded by the Volkswagen Foundation. 

“A lack of amino acids triggered the formation of nanotubes. Deleting a gene, which is involved in the production of a certain amino acid, caused the resulting bacteria to connect to other bacterial cells and − in this way − compensate their nutritional deficiency. However, nanotubes did not form when the required amino acids were supplemented to the growth medium, indicating that the formation of these structures obviously depends on how ‘hungry’ a cell is,” the scientist summarizes the results.

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Supermassive black holes at the cores of galaxies blast radiation and ultra-fast winds outward

Supermassive black holes at the cores of galaxies blast radiation and ultra-fast winds outward | Amazing Science |

By looking at the speed of ambient gas spewing out from a well-known quasar, astronomers are gaining insight into how black holes and their host galaxies might have evolved at the same time. Using the Nuclear Spectroscopic Telescope Array(link is external) (NuSTAR), researchers were able to use the X-ray spectra of an extremely luminous black hole (quasar PDS 456) to detect a nearly spherical stream of highly ionized gas streaming out of it.

The discovery allowed astronomers to measure, for the first time, the strength of ultra-fast black hole winds and show that they are mighty enough to affect the fate of their host galaxies. The evolution of galaxies is connected to the growth of supermassive black holes in their centers. During the quasar phase, a huge luminosity is released as matter falls onto the black hole, and radiation-driven winds can transfer most of this energy back to the host galaxy.

"We know that black holes in the centers of galaxies can feed on matter, and this process can produce winds. This is thought to regulate the growth of the galaxies," said Fiona Harrison of the California Institute of Technology, the principal investigator of NuSTAR and a co-author on a new paper about the results appearing in the Feb. 19 issue of the journal Science. "Knowing the speed, shape and size of the winds, we can figure out how powerful they are.”

Supermassive black holes blast matter into their host galaxies, including X-ray-emitting winds traveling at up to one-third the speed of light. In the new study, astronomers determined that PDS 456, an extremely luminous active black hole, or quasar, has winds that carry more energy every second than what is emitted by more than 1 trillion suns. That's enough of a punch to affect the entire galaxy and its ability to make stars.

“By looking at this huge spherical outflow, we can see a mechanism to explain the correlation between black hole and galaxy formation,” said Bill Craig of Lawrence Livermore National Laboratory and the Space Science Laboratory at University of California, Berkeley.

NuSTAR and the European Space Agency's XMM-Newton simultaneously observed PDS 456, located more than 2 billion light-years away, on five separate occasions in 2013 and 2014. The space telescopes complement each other by seeing different parts of the X-ray light spectrum: XMM-Newton sees low-energy X-rays and NuSTAR sees high-energy X-rays. Their goal was to look for iron, which is blown from the black hole winds along with other matter.

The researchers looked for scattered light signatures from iron atoms originating from the sides of the supermassive black hole. The NuSTAR's higher-energy X-ray data, when combined with observations from XMM-Newton, provided the key information, proving that the winds emanate not in a beam but in a nearly spherical fashion.

With the shape and extent of the winds determined, the researchers could then determine the power of the wind and the degree to which they can quench the formation of new stars. The new report demonstrates that a supermassive black hole and the galaxy that nurtures it are connected by high-speed winds. As the black holes bulk up in size, their winds push vast amounts of matter outward through the galaxy, which ultimately stops new stars from forming.

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New HPV vaccine is effective against 9 strains of the virus

New HPV vaccine is effective against 9 strains of the virus | Amazing Science |

In a world obsessed with curing cancer, prevention is less headline-grabbing, but it's also generally less painful and cheaper. Vaccines for the human papillomavirus (HPV) are a formidable weapon in the arsenal against multiple kinds of cancer, yet the uptake of the vaccine in the US is low, especially when compared to other high-income countries.

According to the President’s Cancer Panel Annual Report 2012-2013, only 33.4 percent of girls in the US complete the course of three HPV vaccines, compared to 60.4 percent in the UK and 71.2 percent in Australia. The vaccination rate for boys is even lower, at less than seven percent—unsurprising given that many public health campaigns specifically target girls.

This is a problem given how common HPV is, and how dangerous it can be. At any given time, one in four Americans is infected with at least one strain of the virus. Almost all sexually active people will be infected with it at some point in their lives. Most infections will be cleared by the immune system, but the remaining cases may lead to cervical, anal, or oral cancer, with approximately 26,000 cases in the US every year.

Two vaccines against HPV have been available for some time. Cervarix is "bivalent", protecting against the two most common cancer-causing strains, HPV-16 and 18. Quadrivalent Gardasil protects against four strains: 6, 11, 16 and 18. However, these aren’t the only HPV strains associated with cancer. A recent paper in the New England Journal of Medicine reports that a new vaccine, Gardasil 9, offers protection against the original four strains, as well as against HPV-31, 33, 45, 52 and 58. The randomized, double-blind clinical trial, conducted in 14,215 women, showed that the new 9-valent Gardasil offered increased protection against genital cancers in women between the ages of 16 and 26.

For diseases where medical treatment is already available and recommended, like the quadrivalent Gardasil vaccine, it's considered unethical to compare a new treatment to placebo. This is because the control group receiving the placebo would be missing out on recommended treatment, putting them at risk. So, in this trial, Gardasil-9 was compared to Gardasil.

The results showed that Gardasil-9 provided the same protection against HPV-6, 11, 16 and 18 as Gardasil, and increased protection against the five additional strains. Overall, the researchers report, the 9-valent vaccine could prevent approximately 90 percent of cervical cancers, compared to Gardasil's 70 percent protection.

There is some evidence that the bivalent and quadrivalent vaccines already provide some protection against additional strains of HPV. A recent paper in Clinical and Vaccine Immunology reporting on the clinical trial for Cervarix reported that the vaccine is more than 96 percent effective against disease associated with strains 16 and 18, and more than 50 percent effective against diseases associated with any HPV strain.

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FDA permits marketing of first direct-to-consumer genetic carrier test for Bloom syndrome

FDA permits marketing of first direct-to-consumer genetic carrier test for Bloom syndrome | Amazing Science |

The U.S. Food and Drug Administration today authorized for marketing 23andMe’s Bloom Syndrome carrier test, a direct-to-consumer (DTC) genetic test to determine whether a healthy person has a variant in a gene that could lead to their offspring inheriting the serious disorder.

Along with this authorization, the FDA is also classifying carrier screening tests as class II. In addition, the FDA intends to exempt these devices from FDA premarket review. The agency plans to issue a notice that announces the intent to exempt these tests and that provides a 30-day period for public comment. This action creates the least burdensome regulatory path for autosomal recessive carrier screening tests with similar uses to enter the market.

“The FDA believes that in many circumstances it is not necessary for consumers to go through a licensed practitioner to have direct access to their personal genetic information. Today’s authorization and accompanying classification, along with FDA’s intent to exempt these devices from FDA premarket review, supports innovation and will ultimately benefit consumers,” said Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health. “These tests have the potential to provide people with information about possible mutations in their genes that could be passed on to their children.”

In general, carrier testing is a type of genetic testing performed on people who display no symptoms for a genetic disorder but may be at risk for passing it on to their children. A carrier for a genetic disorder has inherited one normal and one abnormal allele for a gene associated with the disorder. A child must inherit two abnormal alleles, one copy from each parent, in order for symptoms to appear.

No test is perfect. Given the probability of erroneous results and the rarity of these mutations, professional societies typically recommend that only prospective parents with a family history of a genetic disorder undergo carrier screening. For example, when a gene mutation is expected to be very rare, a positive result for the mutation may have a high probability of being wrong.

Like other home-use tests for medical purposes, the FDA requires the results to be conveyed in a way that consumers can understand and use. This is the same approach the FDA has taken with other over-the-counter consumer products such as pregnancy, cholesterol and HIV tests for home use

While the FDA is not limiting who should or should not use these tests, it is requiring that the company explain to the consumer in the product labeling what the results might mean for prospective parents interested in seeing if they carry a genetic disorder.  

If sold over the counter, the FDA is also requiring 23andMe to provide information to consumers about how to obtain access to a board-certified clinical molecular geneticist or equivalent to assist in pre- and post-test counseling. 23andMe performed two separate studies to demonstrate that their test is accurate in detecting Bloom syndrome carrier status. One study conducted at two laboratories tested a total of 123 samples, including samples from known carriers of the disease. An additional study evaluated 105 samples at two additional laboratories. Both studies showed equivalent results in detecting carrier status of Bloom syndrome when the same samples were tested.

The company also conducted a usability study with 295 people not familiar with the 23andMe saliva collection device to demonstrate consumers could understand the test instructions and collect an adequate saliva sample.

Finally, the company conducted a user study of 302 randomly recruited participants representing the U.S. general population in age, gender, race and education level to show the test instructions and results were easy to follow and understand.

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Four ways healthcare is putting artificial intelligence and machine learning to use

Four ways healthcare is putting artificial intelligence and machine learning to use | Amazing Science |

Several startups are applying AI to make healthcare delivery more efficient and automated. It’s worth a look at the diverse applications for AI across healthcare including biotech and health IT, since these are some areas where it is having a significant impact from informing healthcare decisions to speeding up the selection of targets for drug development.

Medication adherence AiCure uses mobile technology and facial recognition to determine if the right person is taking a given drug at the right time. It uses mobile devices to capture patient data from an application. It uses automated algorithms to identify patients, the medication and the process of medication ingestion. That data gets transmitted in real-time back to a clinician through a HIPAA-compliant network. Clinicians can confirm that the patients are taking their medication as directed. But its technology can also be used to flag adverse events.

Next IT developed Alme Health Coach to get a deeper dive on why people aren’t taking their meds. It is a relative newcomer to healthcare. It developed “virtual assistants” to guide and better understand consumer problems across areas like banking, retail and money management. Part of the AI component involves repeating what users say to verify and clarify thoughts that are transmitted back and forth by users. The health coach is designed to be configured for specific diseases, medications and treatments. The health coach may be synched with the user’s sleep alarm so it can trigger questions like how they slept and that can prompt questions about their medication. The idea is to collect actionable data that doctors can use to better work with patients, providing the patient agrees they can share the data.

Healthy behavior Welltok tapped IBM’s Watson superbrain to support its vision of connecting consumers with personalized activities. Its Caféwell Concierge app uses Watson’s natural language processing abilities to understand users goals and provide the right balance of nudges and alerts so it can meet those targets and reward them. Watson is also part of a broader mission in healthcare to provide more targeted care, such as guiding oncologists on the most appropriate cancer treatment options based on the patients medical history and other data.

Support care givers Automated Insights put its natural language generation platform Wordsmith to work in a collaboration with Great Call — a mobile app developer. GreatCall Link is an app that allows friends and family members to learn about what’s going on with a GreatCall device carrier the app connects with.The app creates a way to notify them when a connected device is used to call for help. The app is equipped with patented GPS technology so it also shows the location of the device (and the user). Underscoring the level of interest in AI, Automated Insights was acquired this week by Vista Equity Partners and sports data company, STATS.

Drug development Biotech companies are also combining artificial intelligence and big data to identify new drug compounds, such as Cloud Pharmaceuticals and Berg. Johnson & Johnson and Sanofi are using Watson to find new targets for FDA approved drugs.

Dagmawi hailu's curator insight, March 27, 2015 5:13 AM

One of the areas that is seeing great benefit from the advancement of AI is medical. It has used the technology to its advantages by assigning it to tasks and projects that will make the medical service more breeze and flawless. Support for care givers, health development, medication adherence and drug development are the areas AI is giving incalculable use to the medical world.

Dagmawi hailu's curator insight, March 27, 2015 5:15 AM

Areas of medication adherence, the support care givers, drug development and health behaviors are areas where the healthcare is putting the advancement of AI to good use.

Josh Oj's curator insight, March 27, 2015 6:16 AM

A.I. is already being used in a variety of medical situations, so what does the future hold?

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Perfect colors, captured with one ultra-thin nanotech lens

Perfect colors, captured with one ultra-thin nanotech lens | Amazing Science |

 Most lenses are, by definition, curved. After all, they are named for their resemblance to lentils, and a glass lens made flat is just a window with no special powers. But a new type of lens created at the Harvard School of Engineering and Applied Sciences(SEAS) turns conventional optics on its head.

A major leap forward from a prototype device demonstrated in 2012, it is an ultra-thin, completely flat optical component made of a glass substrate and tiny, light-concentrating silicon antennas. Light shining on it bends instantaneously, rather than gradually, while passing through. The bending effects can be designed in advance, by an algorithm, and fine-tuned to fit almost any purpose.

With this new invention described today in Science, the Harvard research team has overcome an inherent drawback of a wafer-thin lens: light at different wavelengths (i.e., colors) responds to the surface very differently. Until now, this phenomenon has prevented planar optics from being used with broadband light. Now, instead of treating all wavelengths equally, the researchers have devised a flat lens with antennas that compensate for the wavelength differences and produce a consistent effect—for example, deflecting three beams of different colors by the same angle, or focusing those colors on a single spot.

“What this now means is that complicated effects like color correction, which in a conventional optical system would require light to pass through several thick lenses in sequence, can be achieved in one extremely thin, miniaturized device,” said principal investigator Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at Harvard SEAS.

Donald Schwartz's curator insight, February 20, 2015 11:19 AM

Less glass is good. I'm so excited, I just can't hide it. 

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Researchers Build Atomically-Thin Gas and Chemical Sensors

Researchers Build Atomically-Thin Gas and Chemical Sensors | Amazing Science |

The relatively recent discovery of graphene, a two-dimensional layered material with unusual and attractive electronic, optical and thermal properties, led scientists to search for other atomically thin materials with unique properties. Molybdenum disulfide (MoS2) has proved to be one of the most promising. Single-layer and few-layer molybdenum disulfide devices have been proposed for electronic, optoelectronic and energy applications. A team of researchers, led by engineers at the University of California, Riverside’s Bourns College of Engineering, have developed another potential application: sensors.

“The sensors are everywhere now, including in smart phones and other portable electronic devices,” said Alexander Balandin, UC Presidential Chair and professor of electrical and computer engineering at UC Riverside, who is the lead researcher on the project. “The sensors we developed are small, thin, highly sensitive and selective, making them potentially ideal for many applications.”

Balandin and the graduate students in his lab built the atomically thin gas and chemical vapor sensors from molybdenum disulfide and tested them in collaboration with researchers at the Rensselaer Polytechnic Institute in Troy, N.Y. The devices have two-dimensional channels, which are great for sensor applications because of the high surface-to-volume ratio and widely tunable concentration of electrons.

The researchers demonstrated that the sensors, which they call molybdenum disulfide thin-film field-effect transistors (TF-FET), can selectively detect ethanol, acetonitrile, toluene, chloroform and methanol vapors.

The findings were published in a recent paper, “Selective chemical vapor sensing with few-layer MoS2thin-film transistors: Comparison with graphene devices,” in the journal Applied Physics Letters.

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Infrared camouflage adhesive tape developed

Infrared camouflage adhesive tape developed | Amazing Science |

US scientists have developed an adhesive tape that can help objects match the infrared reflectance of their surroundings and disguise them from being seen by infrared cameras. The flexible coating – based on a protein found in cephalopod skin – can moderate reflectance simply by stretching and may find application in military camouflage kit.

Cephalopods – such as squid, octopuses and cuttlefish – are nature’s masters of disguise. Their skins contain iridophores, cells that reflect and manipulate incident light to spectacular effect. Their plasma membranes fold to encompass lamellar-like platelets containing reflectin. Reversible phosphorylation of reflectin changes the size and structure of the lamellae, changing the iridophore’s reflectance across the visible spectrum.

Alon Gorodetsky’s group at the University of California, Irvine, has developed a method for coating a thin-film of reflectin onto the surface of a flexible and transparent adhesive substrate layered with graphene oxide. These ‘stickers’, transparent under normal light, can be stuck onto any surface, including conventional camouflage with precise patterning. The reflectance can be controlled by stretching, and upon heating, the inexpensive material returns to its original state. ‘The protocols for making it are very scalable – putting a thin film on a standard roll of tape isn’t difficult and requires fairly little material so it shouldn’t be much more expensive than ordinary sticky tape one finds in their desk,’ Alon tells Chemistry World.

Besides stealth applications, Gorodetsky suggests that advanced versions of these materials might be used in glass coatings to regulate seasonal temperature. The team are keen to push the reflectance of reflectin-inspired materials as far as possible into the thermal infrared. ‘We hope to eventually develop autonomous clothing-integrated devices that will regulate how a person radiatively exchanges heat with their environment.’ The potential applications are exciting: ‘Wouldn’t it be neat if you had a jacket which could adapt to keep you cool on warm days and warm on cold days?’ adds Gorodetsky.

Jason Slinker, an optoelectronic materials expert at the University of Texas at Dallas, US, says the material should draw great interest from the apparel industry. ‘Such a stable, reversible, responsive, and inexpensive means of enhancing clothing with broad color changing capabilities will have applications in safety and camouflage as well as aesthetic implications in fashion.’

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Lunar moths shed light on how to fool sonar from bats

Lunar moths shed light on how to fool sonar from bats | Amazing Science |

It’s hard to hide from a bat: The camouflage and mimicry techniques that animals use to avoid becoming a meal aren’t much use against a predator using echolocation. But a new study shows that moths can outsmart sonar with a flick of their long tails.

The study appearing in the Proceedings of the National Academy of Sciences shows luna moths spin their trailing hindtails as they fly, confusing the sonar cries bats use to detect prey and other objects.

The collaborative work between University of Florida and Boise State University researchers is a first step in determining why bats are lured into striking a false target. The findings could have implications on sonar development for the military, said Akito Kawahara, assistant curator of Lepidoptera at the Florida Museum of Natural History on the UF campus, who was UF’s research leader on the project.

“This finding expands our knowledge of anti-predator deflection strategies and the extent of a long-standing evolutionary arms race between bats and moths,” Kawahara said.

The study is the first to show that insects use this type of trickery to thwart bats. Other animals also might use acoustic deflection strategies, said lead author Jesse Barber, a biologist at Boise State University. Using high-speed infrared cameras and ultrasonic microphones, the researchers watched brown bats preying on moths. Luna moths with tails were 47 percent more likely to survive an attack than moths without tails. Bats targeted the tail during 55 percent of the interactions, suggesting the moths may lure bats to the tails to make an attack more survivable.

While more than half of the 140,000 species of nocturnal moths have sonar-detecting ears that provide a similar level of protection, more than 65,000 species lack this defense, Kawahara said. “When you pit them against bats, bats can’t find the moths. They go to the tail instead of the head,” Kawahara said. “When you look at Lepidoptera collections, you see moths with really short tails and some with extremely long tails. This also is an example of the important role biological collections serve as repositories of patterns and processes of biodiversity.”

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Martian mystery cloud defies explanation

Martian mystery cloud defies explanation | Amazing Science |

A mysterious plume that appeared on Mars in 2012 is testing scientists’ understanding of the Martian atmosphere. Amateur astronomers spotted the bizarre feature rising off the edge of the red planet in March and April of 2012. It looked like a puff of dust coming off the surface, but it measured some 200 to 250 kilometers high. That is much higher than would be expected from the lower-altitude dust storms that rage across the planet.

Now a team of astronomers proposes that the plume was either a cloud of ice particles or a Martian aurora. But neither possibility fully explains the plume — raising new questions about the state of the Martian atmosphere. The study, led by astronomer Agustín Sánchez-Lavega of the University of the Basque Country in Bilbao, Spain, is published on 16 February in Nature1.

“This observation is a big surprise,” says Aymeric Spiga, a planetary scientist at the University of Pierre and Marie Curie in Paris, who was not involved in the work. “Another puzzle on Mars!”

The plume first appeared on 12 March 2012 as a small bump on the dawn side of Mars’s southern hemisphere. It changed shape over the next 11 days, morphing from blobs to pillars and other forms. Within weeks another plume appeared, this one also lasting about a week and a half. The plumes' sheer height is the hard thing to explain. To find an answer, Sánchez-Lavega’s team coordinated observations from amateur astronomers, and searched imagery from Mars spacecraft.

The simplest explanation is that the dust storms that frequently whirl across Mars might have kicked dust up to high altitudes. But dust has not been seen at altitudes higher than about 50 kilometres in the Martian atmosphere. And even that requires unusual weather conditions to funnel dust upwards, in an event that Spiga dubbed 'rocket dust storms' in a 2013 paper. A more plausible explanation is that the plumes were formed by shards of frozen carbon dioxide or water vapour, says Sánchez-Lavega. But their existence would require the atmosphere to be much colder than models predict for that altitude.

Sánchez-Lavega and his colleagues are still working to resolve the mystery. NASA's MAVEN spacecraft, one of the flotilla of US and Indian probes currently orbiting Mars, would be able to see a plume if it happened to be looking at the right place at the right time — but has not seen anything like it yet. And amateur astronomers watched Mars closely in April 2014, when the planet was last closest to Earth and saw no high-altitude plumes. The next such opportunity comes in 2016.

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