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Reproducing efficiently in captivity is crucial for the survival of many wildlife species, yet reproductive success is often lower than in the wild. Currently, many zoo population management strategies prioritise the genetic diversity of captive populations. Scientists now argue that a broader perspective is required which also includes behaviour, life-history, husbandry and environmental considerations. This would improve breeding success in zoos and the maintenance of the diversity of traits, behaviours, and phenotypes of threatened species. In a paper published recently in the scientific "Journal of Zoo and Aquarium Research" they compare different population management approaches and conclude that prioritizing genetic factors to the exclusion of all others may have detrimental effects: For example, in small groups of unrelated adults, conflicts are likely to be more frequent than in larger groups with relatives present who had the chance to develop differentiated socialisation and learning repertoires.

Many species of birds and mammals reproduce better in the wild than in captivity. When wild populations are threatened, it is of utmost importance to conservation that captive populations are healthy and sustainable. In a new paper, wildlife biologists Werner Kaumanns (LTM-Research and Conservation), Nilofer Begum (Freie Universität Berlin) and Heribert Hofer (Leibniz Institute for Zoo and Wildlife Research) evaluate decades of scientific literature on the reproduction of captive populations and compared two well-known population management paradigms. The "small population paradigm" focuses on the genetic reservoir of the species and attempts to maximise genetic diversity within the captive populations, for example by exchanging mating partners frequently or by avoiding groups of closely related individuals. In the "declining population paradigm" on the other hand measures target the causes of population decline and thereby reproduction processes and conditions. "We argue that under the latter paradigm better management options can be developed without necessarily contradicting genetic assessments and their relevance to population management", says lead author Kaumanns.

The authors argue that, next to survival, evolution places a heavy emphasis on reproduction, the success of which profoundly affects the animal's contribution to future generations. "This means that many key traits and evolutionary adaptations are linked to reproduction", senior author Hofer explains. "It is evident that animals are designed for breeding, which means that group sizes, socialisation and learning repertoires, behaviours, spatial requirements and other traits and contexts usually contribute to reproductive success." For example, the behavioural skills and experience of a primate female in infant rearing are as relevant to reproductive success and recruitment for population management as her genetic status. "It is necessary that appropriate conditions are provided in zoos to ensure that females can acquire these skills", Hofer says. This can require the presence of aunts, mothers or other group members, an appropriate demography and group composition.

This perspective is not restricted to primates: providing the setting for mothers to gain the necessary experience would also be beneficial in elephants and other species with complex societies, such as spotted hyenas. "It is, therefore, recommended that key traits play a dominant role in management plans and husbandry guidelines", Nilofer Begum, a doctoral student at Freie Universität Berlin, adds. If captive breeding conditions do not respect natural breeding conditions, traits can function as constraints and the diversity of traits, behaviours and phenotypes may be threatened. This may mean that in practice, zoos might sometimes concentrate on fewer animals, develop a more flexible husbandry system that better incorporates essentials of a species' niche or habitat, and ensure that social groups foster generational learning, problem solving and the resolution of conflicts.

The Super Steel project led by Professor Huang Mingxin at the Department of Mechanical Engineering of the University of Hong Kong (HKU), with collaborators at the Lawrence Berkeley National Lab (LBNL), has made important breakthrough in its new super D&P steel (produced using a new deformed and partitioned method) to greatly enhance its fracture resistance while maintaining super strong in strength for advanced industrial applications.

The findings were published in Science on 8 May 2020 in the paper titled "Making Ultrastrong Steel Tough by Grain-Boundary Delamination".

Steel is a common alloy. Material scientists and engineers are continually seeking to develop new generation steel materials which are easier to extend and elongate (ductility) into different forms and structures, higher in resistance to deformation (strength) and fracture (toughness), light in weight and low in production cost.

The task has been difficult. The conventional view is that raising the performance of one metallic property, whether in strength, ductility or toughness, will undermine one or more of the others. For example, an increase in strength will inevitably make the metal more brittle (known as the strength-toughness trade-off); or less flexible to be extended or elongated into different shapes. (strength-ductility trade-off).

"In this latest breakthrough in super D&P steel, we attained an unprecedented strength-toughness combination which can address a major challenge in safety-critical industrial applications - to attain an ultra-high fracture toughness so as to prevent catastrophic premature fracture of structural materials. The breakthrough also changes the conventional view that attaining high strength will be at the expense of deteriorating toughness, which invariably leads to the embrittlement of structural materials and greatly limits their application," said Professor Huang.

The team had earlier raised significantly the D&P steel's strength-ductility performance (Note 1), the super D&P steel hence attains excellent performance in all three metallic properties at an unprecedented high-level not reached by any steel materials before.

Several patents in US, EU and China have been filed. The team has been liaising with industrial partners to generate prototypes of high-strength bridge cable, bullet proof vest and car spring with the super steel for further tests and trials to be conducted. The latest breakthrough in the D&P steel, made in collaboration with Professor Robert O. Ritchie's research team at the Lawrence Berkeley National Lab (LBNL) and UC Berkeley, results in the steel a yield strength resistance against deformation of ~2GPa, a superior fracture toughness of 102MPažm½, and a good uniform elongation of 19%. (Fig.1 and Fig.2).

The team has also made an important scientific discovery in the structure of the super D&P steel. The super steel has a unique fracture feature in which multiple micro-cracks are formed below the main fracture surface, through a novel "high-strength induced multi-delamination" toughening mechanism. These micro-cracks can effectively absorb energy from externally applied forces, resulting in the steel's much higher toughness resistance compared to existing steel materials.

Currently, high strength steel for bridge cables has a yield strength lower than 1.7 GPa ~, and a fracture toughness lower than 65 MPažm½; high strength armoured steel used in armoured cars has a similar maximum strength - toughness combination. The toughness level that can be attained by the D&P steel is hence much higher than that of existing steel materials, while maintaining super strong in strength.

Steel piano wire, for instance, has an ultra-high strength ranging from 2.6 to 2.9 GPa to resist deformation and to keep the instrument in tune, which is achieved at the expense of toughness and is in turn very brittle.

Meanwhile, the cost of raw materials of the D&P steel is only 20% of the maraging steel currently used in aerospace (e.g. Grade 300, whose yield strength and fracture initiation toughness are 1.8 GPa and 70 MPaž m½, respectively).

"D&P steel has other advantages such as simple industrial processing and low raw-materials cost. It can be produced by conventional rolling and annealing processes, as such no complex fabrication routes and special equipment are required," said Miss Li LIU, the first author of the journal article and a PhD student supervised by Professor Huang.

"We have made a big step closer to industrializing the novel super steel. It demonstrates a great potential to be used in various applications including superior bulletproof vests, bridge cables, lightweight automobile and military vehicles, aerospace, and high strength bolts and nuts in the construction industry." Professor Huang added.

During the COVID-19 pandemic, as demand for SARS-CoV2 diagnostic testing has far outweighed the supply, academic research scientists have begun converting their labs to testing facilities. In a paper published May 10 in Med, a team of investigators from Boston University School of Medicine and Boston Medical Center (BMC) outline how they adapted their lab to test patient samples for SARS-CoV2, and they provide a blueprint for other labs that want to do the same thing.

"As with other basic biology labs across the country, we were forced to shutter operations due to the pandemic," says senior author George Murphy (@DrGJMurphy), an Associate Professor of Medicine in the Division of Hematology and Oncology. "We saw that our friends and colleagues at Boston Medical Center were going into battle on the front lines of this pandemic, but that they were having to wait seven to 10 days for results from state and commercial laboratory facilities. This was unacceptable to us, and we decided we needed to take action."

Murphy is normally co-director of the Boston University and Boston Medical Center (BMC) Center for Regenerative Medicine (CReM) and focuses on stem cell research. As stem cell and molecular biologists, he and the members of the lab had extensive experience developing and running the type of quantitative, real-time reverse transcriptase polymerase chain reaction (qRT-PCR) assay that was needed to detect the presence of viral RNA in patient samples.

The bigger challenge was adapting their lab to the strict policies required to run a Clinical Laboratory Improvement Amendments (CLIA)-certified, College of American Pathologists (CAP)-accredited diagnostic lab. The team requested and received emergency permission from the FDA to repurpose the lab, and they began operating in less than a week. As of April 20, 2020, they had already tested more than 3,000 samples, with a sample turnaround time that's under 24 hours. Nearly 45% of those tests were positive, a large number due in part to the high-risk population served by BMC, the largest safety net hospital in New England.

"For about a month or so, we were the only game in town," Murphy notes. "Results from samples that were sent out to large commercial labs were taking up to a week, but even a wait-time of 24 hours delays the ability to make decisions about whether or not someone needs to be isolated and whether precious PPE [personal protective equipment] should be used."

The team developed a test that could be done with technologies and reagents that are likely to remain available. The test was also designed with the ability to use different reagents at each step of the process. "Our 'home-brew' assay is extremely flexible, allowing us to slot in various reagents at multiple points and eliminating potential supply-chain issues," Murphy says.

He doesn't expect the need for testing to decline any time soon. "Although we have gotten through the early stages of this pandemic, which involved the testing of critically ill and symptomatic patients during a time of acute need, everyone is going to soon need to transition into asymptomatic and surveillance testing. It may be extremely difficult for large commercial labs to contend with the enormous number of samples this will entail," Murphy says. "We decided to share what we did so that other institutions can implement their own in-house testing."

The team is also looking at expanding to other kinds of assays, including saliva-based tests.

Murphy credits his colleagues and coauthors, including laboratorian Chris Andry, pathologist Nancy Miller and bioinformaticist Taylor Matte, for putting together this testing program so quickly. “We think it’s important for the public to see something positive in these very challenging times,” he concludes. “This project was a wonderful example of collaboration and teamwork in which scientists, clinicians, diagnostic laboratory technicians, and administrators came together to solve a seemingly insurmountable problem.”

Sound is one of the ancient physical phenomena people studied. Researcher have been exploring the mystery of sound all the time. In recent years, more and more attention has been applied to the study of near-field acoustics. Near-field evanescent wave is a common wave pattern. Its intensity decreases exponentially with distance and tends to be highly spatially confined. Because near-field evanescent wave can carry information and have a high energy density, it has a very broad application prospect in efficient communication, wireless energy transfer and so on. Among these practical applications, one of the main goals is to achieve the selective directional coupling. However, the near-field selective coupling is difficult to realize because it does not have directional properties like the far-field wave. Exploitations of near-field waves are limited due to the lack of fundamental understandings about inherent near-field symmetry and directional coupling at subwavelengths, especially for longitudinal waves.

Although it is still a difficult challenge to selectively regulate evanescent wave in subwavelength, its value is self-evident. It can not only promote our understanding the physics nature of the near-field wave, but also lead the development of richer functional devices in "sound, light, vibration, heat" and so on.

Now, most works about selective regulation of near-field waves usually base on optics by using specific incident excitation conditions (e.g., left- or right-handed light) and complex anisotropic resonance structures. However, compared with the transverse wave, the longitudinal wave lacks abundant natural polarization degrees of freedom. So, the study and exploitations of near-field longitudinal waves are severely limited. Recently, Yang Long, Hao Ge et al. from Tongji University and Nanjing University made an exciting progress. They proposed a detailed scheme to realize the selective coupling of near-field longitudinal wave based on the inherent geometric properties and symmetry analysis of evanescent wave in experiment and theory.

Symmetry is a common and interesting phenomenon in our life and plays an important role in physics. Based on symmetry, Dirac proposed that electrons have positrons and negative electrons. Symmetry not only has the geometric beauty on the surface, but also has rich physical connotations. In this work, the authors propose a scheme for the directional design of general near-field waves from the perspective of symmetry.

The dynamic features of near-field waves can be described by three geometrically-orthogonal physical vectors: time-averaged energy flow (Poynting vector) J, reactive power R and spin angular momentum (SAM) s.(Fig.(b)). According to the inherent geometrical properties of these quantities, the researchers obtained their different symmetries--the Poynting vector J, the reactive power R, and the SAM s are individually invariant under parity-time, time-reversal and parity transformations, respectively (Fig.(c)). Owing to the inherent geometry and symmetry of these quantities, the near-field acoustic modes carry their symmetry properties as well and the different combinations of multiple near-field waves will have different symmetries. For example, if a square and a circle are superimposed, the combined new figure will have some new symmetries.

Regarding directional coupling, in the past, one usually realise different propagation directions through spin quantity locking by using different spins and chirality, based on the quantum-like spin hall effect of waves. In 2018, the research group of Tongji University published a paper to reveal the unique spin angular momentum of longitudinal wave, and realized directional coupling based on spin quantity locking in experiment with Berkeley research group. In this new work, the authors proposed a solution to achieve near-field acoustic wave directional coupling with Janus and Huygens sources, which goes further than spin locking with acoustic spin. Janus was the god of the gate in Roman mythology. He had a face on each side of his head, so he was also known as the god of two faces (Fig.(a)). As the name suggests, the two-sided Janus source will selectively only couple with one side of the near-field pattern (in this work with the upper or lower surface), a property that is unique to the near-field. However, Huygens source is a one-way selection regardless of the far field and the near field. In this paper, it is only coupled to the left side or the right side, which is perpendicular to the direction of the Janus source.

But how can we realize these in near-field acoustics? According to the acoustic radiation theory, sound source can be regarded as the linear superposition of monopole, dipole and quadrupole. These superposition terms are usually used to excite fertile far-field acoustic wave modes. Therefore, Janus, Huygens and spin sources can be realized by different combinations of acoustic modes. Based on the above analysis, the researchers built three acoustic signal sources by placing five speakers as cross bending shape which amplitude and phase can be independently controlled (Fig.(d)). The five speakers can realize arbitrary combination of acoustic monopoles and dipoles. According to the near-field acoustic coupling theory they proposed, the three signal sources have different symmetry properties:

1) Acoustic Janus source is parity anti-symmetric and time symmetric.

2) Acoustic Huygens source is parity-time symmetric.

3) Acoustic spin source is parity symmetric and time anti-symmetric.

Interestingly, the three sources could be excited using the same J, R, s, respectively.

To verify the symmetry-selected directional near-field excitations in experiments, the researchers selectively activated different mode combinations of loudspeakers in the comb-like structure to realize the three sources (Fig.(e)). For a normal source, when the signal is motivated in the middle of the system, the sound will be transmitted along the all the upper and lower boundaries (total four branches). However, when the signal source has different symmetry, the selective directional transmission of sound waves is found (Fig.(f)): 1) the Janus source is selectively coupled to a unilateral (upper or lower) surface; 2) Huygens source can excite unidirectional (left or right) surface modes due to the directional transport character of the energy flow. 3) The acoustic spin source is excited diagonally.

This is in good agreement with previous theoretical predictions. In addition, when different sources are excited, the symmetry of spin angular momentum in acoustic near-field wave has been fully discussed and experimentally verified.

"This work opens a new door for the symmetry research of near-field evanescent wave, which can guide the directional design of near-field wave sources with novel properties," Professor Jie Ren said. "In the future, it is worth applying to the directional transportation of phonon information and energy in the on-chip nano-phononic devices."

Quantum physics deals with microscopic systems such as atoms and light particles. It is a theory that makes it possible to calculate the probabilities of the possible results of any measurement taken on these systems. However, what happens during the measurement was a mystery. A team of researchers from the University of Seville, the University of Stockholm (Sweden) and the University of Siegen (Germany) has, for the first time, managed to "film" what happens during the measurement of the quantum system.

To do that, they used a strontium ion (an electrically-charged atom) trapped in an electrical field. The measurement of the ion last barely a millionth of a second but the researchers have managed to make a "film" of the process by reconstructing the quantum state of the system at different moments. The results confirm one of the most subtle predictions in quantum physics.

"The experiment is interesting for two reasons, according to the teacher Adán Cabello, of the Department of Applied Physics II at the University of Seville. "On the one hand, it shows the change of quantum state during a measurement is not instant _ as many believe - but that it happens gradually". Also, "the experiment demonstrates that the quantum measurements that preserve quantum states with the maximum information are real processes that occur in nature and are not just theoretical idealizations".

The result of the experiment can be summarised in an animated GIF that shows was happens to the quantum state of the ion during this millionth of a second. The state can be visualised using a three-dimensional board. The heights of the towers indicate the degree of superposition of the possible quantum states. The film shows how, during the measurement, some of the superpositions are lost - and how loss is gradual - while others are preserved just as it has to happen in an ideal quantum measurement.

The sprawling 11,500-year-old stone Göbekli Tepe complex in southeastern Anatolia, Turkey, is the earliest known temple in human history and one of the most important discoveries of Neolithic research.

Researchers at Tel Aviv University and the Israel Antiquities Authority have now used architectural analysis to discover that geometry informed the layout of Göbekli Tepe's impressive round stone structures and enormous assembly of limestone pillars, which they say were initially planned as a single structure.

Three of the Göbekli Tepe's monumental round structures, the largest of which are 20 meters in diameter, were initially planned as a single project, according to researchers Gil Haklay of the Israel Antiquities Authority, a PhD candidate at Tel Aviv University, and Prof. Avi Gopher of TAU's Department of Archaeology and Ancient Near Eastern Civilizations. They used a computer algorithm to trace aspects of the architectural design processes involved in the construction of these enclosures in this early Neolithic site.

Their findings were published in Cambridge Archaeological Journal in May.

"Göbekli Tepe is an archaeological wonder," Prof. Gopher explains. "Built by Neolithic communities 11,500 to 11,000 years ago, it features enormous, round stone structures and monumental stone pillars up to 5.5 meters high. Since there is no evidence of farming or animal domestication at the time, the site is believed to have been built by hunter-gatherers. However, its architectural complexity is highly unusual for them."

Discovered by German archaeologist Dr. Klaus Schmidt in 1994, Göbekli Tepe has since been the subject of hot archaeological debate. But while these, and other early Neolithic remains, have been intensively studied, the issue of architectural planning during these periods and its cultural ramifications have not.

Most researchers have made the case that the Göbekli Tepe enclosures at the main excavation area were constructed over time. However, Haklay and Prof. Gopher say that three of the structures were designed as a single project and according to a coherent geometric pattern.

"The layout of the complex is characterized by spatial and symbolic hierarchies that reflect changes in the spiritual world and in the social structure," Haklay explains. "In our research, we used an analytic tool -- an algorithm based on standard deviation mapping -- to identify an underlying geometric pattern that regulated the design."

"This research introduces important information regarding the early development of architectural planning in the Levant and in the world," Prof. Gopher adds. "It opens the door to new interpretations of this site in general, and of the nature of its megalithic anthropomorphic pillars specifically."

Certain planning capabilities and practices, such as the use of geometry and the formulation of floor plans, were traditionally assumed to have emerged much later than the period during which the Göbekli Tepe was constructed -- after hunter-gatherers transformed into food-producing farmers some 10,500 years ago. Notably, one of the characteristics of early farmers is their use of rectangular architecture.

"This case of early architectural planning may serve as an example of the dynamics of cultural changes during the early parts of the Neolithic period," Haklay says. "Our findings suggest that major architectural transformations during this period, such as the transition to rectangular architecture, were knowledge-based, top-down processes carried out by specialists.

"The most important and basic methods of architectural planning were devised in the Levant in the Late Epipaleolithic period as part of the Natufian culture and through the early Neolithic period. Our new research indicates that the methods of architectural planning, abstract design rules and organizational patterns were already being used during this formative period in human history."

Next, the researchers intend to investigate the architectural remains of other Neolithic sites throughout the Levant.

Anyone who's ever tried to find something in a hurry knows how helpful it is to think about the lost item's color, size and shape. But surprisingly, traits of an object that you can't see also come into play during a search, Johns Hopkins University researchers found.

When participants were asked to spot everyday objects in clutter, they found them about 20 percent faster if they could factor in latent physical traits like hardness or softness - even though people had no idea that they were considering those factors.

"What makes the finding particularly striking from a vision science standpoint is that simply knowing the latent physical properties of objects is enough to help guide your attention to them," said senior author Jason Fischer, a cognitive neuroscientist in the university's department of Psychological and Brain Sciences. "It's surprising because nearly all prior research in this area has focused on a host of visual properties that can facilitate search, but we find that what you know about objects can be as important as what you actually see."

The findings are published in the Journal of Experimental Psychology: General.

Fischer's Dynamic Perception Lab studies how people's intuitive understanding of physical properties and dynamics influences how they interact with their everyday environments, and also how people focus on the things they need to when there is so much to see in the world at any given moment. Those lines of research come together here, as the team wondered if someone's knowledge of objects' physical attributes would influence their attention in a visual search.

For instance, people know through experience that eggs are light and fragile, and canned products are heavy and sturdy. When bagging those things at the grocery store, people would likely put the heavy cans at the bottom of a bag and the fragile eggs on top. But if you can't see the fragility or the heaviness, you just inherently know it, would that knowledge help you find something?

To get at the answer, lead author, graduate student Li Guo, ran a series of visual search experiments where people were asked to locate everyday objects amid clutter. The target was sometimes differentiated by its hardness. Guo and the team found that participants implicitly used the hardness distinction to locate a target more quickly, even though none reported being aware that hardness was relevant.

"You're automatically leveraging what you know about hardness to avoid being distracted by the other things," Guo said, as Fischer added: "If you are searching for a sweater in a cluttered room, without any awareness of doing so you are able to avoid wasting time searching through the hard objects in the room and instead focus on the soft ones."

The more items in the search, the greater the benefit of being able to differentiate them through hardness, the team found. The benefit existed even when participants were shown line drawings. And when the team tracked where participants looked while searching, they found that participants wasted less time looking at objects that didn't have the correct hardness or softness.

"To me what this says is that in the back of our minds, we are always evaluating the physical content of a scene to decide what to do next," Fischer said. "Our mental intuitive physics engines are constantly at work to guide not only how we interact with things in our environment, but how we distribute our attention among them as well."

The team hopes to build on these findings by studying how what people intuitively know about the physics of objects might help them predict what's going to happen next in an environment.

The novel fibres' latest advances, published this week in Nature Photonics, have underlined the technology's potential for next generation optical interferometric systems and sensors.

Hollow-core optical fibres combine the free-space propagation performance of the most advanced interferometers with the length scales of modern optical fibres by guiding light around bends in an air or vacuum filled core.

Researchers are engaging with industry partners, collaborating with the National Physical Laboratory and exploiting a UK network in the Airguide Photonics programme as they further expand the impact of the discovery.

Professor Francesco Poletti, Head of the Hollow Core Fibre Group, says: "By eliminating the glass from the centre of the fibre, we have also eliminated the physical mechanisms by which the polarisation purity of an input beam can be degraded. As a result, our fibres provide qualities that represent a paradigm shift toward a huge leap in performance.

"With an attenuation as low as 0.28 dB/km and the prospect of soon achieving levels potentially below the Rayleigh scattering limit of conventional fibres, such waveguiding structures could soon provide vacuum-like guidance purity and environmental insensitivity at bespoke wavelengths and over hundreds of kilometres for the next generation of photonics-enabled scientific instruments."

Propagating light waves while preserving all of their essential attributes is a fundamental concern for all applications that use light to sense the environment or to transmit data and power. High-performance interferometers, gyroscopes and frequency combs use the wavelength of light as a miniature ruler to measure distances, rotation speed and time with incredibly accurate precision. They all rely on the transmission of light beams with the highest possible spatial, spectral and polarisation purity.

To achieve the best possible performance, scientists currently need to propagate light through free-space in a vacuum, such as for example in the 4 km arms of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the USA. However, these advanced interferometers are extremely expensive and often impractical at even much shorter length scales. Glass optical fibres offer a more pragmatic and portable alternative in sensing technologies but degrade polarisation purity and suffer from detrimental nonlinear effects.

Hollow-core fibres overcome all of these challenges to enhance the potential of optical interferometric systems and sensors, for example within optical gyroscopes that form the core of inertial navigation systems or for the flexible delivery and coherent combination of intense polarised radiation for the next generation of MegaWatt lasers.

This latest Southampton research was sponsored by the European Union funded LightPipe Project, which builds upon a decades of work at the Zepler Institute's renowned Optoelectronics Research Centre.

The Centre and its Director Professor Sir David Payne have played a leading role in the development of optical fibre technology for applications requiring control of the polarisation states of light. Work in this area also led to the creation of spinout company Fibercore, which has established itself as a global market leader in the production of polarisation maintaining optical fibres.

Professor Sir David Payne, said, "There are numerous applications in optics that require strict polarisation control, such as when two beams interfere to sense tiny changes caused by gravitational waves, or rotation sensing in fibre gyroscopes. The ideal way to transport light is in an optical fibre, but that normally leads to an uncertain, wandering polarisation state and drift in the sensor. It is a great surprise to find that certain types of hollow-core fibre can preserve a stable polarisation over long distances and this observation will have a huge impact on next-generation optical sensors.

"Hollow-core fibres continue to amaze us in ways that appear as if the fibre was not there - just like a vacuum with no diffraction."

The rainforest fjords of Southeastern Alaska harbour one of the highest concentrations of lichen diversity found anywhere on Earth, according to a new study spearheaded by University of Alberta scientists.

An international team of researchers led by Toby Spribille, assistant professor in the Department of Biological Sciences at the Faculty of Science, details the names and habitats of lichens, a symbiosis of fungi and algae in Alaska's Glacier Bay National Park.

The researchers found more than 900 species of lichen, including 27 new, never-seen-before species "This level of novelty biodiversity is usually associated with 'lost valleys' in the tropics," says Spribille, Canada Research Chair in Symbiosis. "To find this in Southeast Alaska really speaks to how little we still know about coastal rainforests. There are so many new species to science that if you know what to look for, you can average one new species to science per day of field work."

The authors compared cumulative numbers of lichens in four different national parks in southern Alaska and found that together, the parks contain more than 1300 species. This work highlights the importance of understanding local biodiversity for nature conservation. Each national park is home to many species not found in the other parks.

Within Glacier Bay National Park alone, each fjord was different. "Of 950 species, we found only 14 species common to all sectors of Glacier Bay," added Spribille. "It makes you wonder what remains to be discovered in all the areas we couldn't get to."

The research team expresses hope that the insights from Glacier Bay National Park will help guide decision-making in other parts of the coastal rainforest ecosystem.

"At high latitudes, biodiversity is locked up in other groups of organisms--and in Alaska, lichens are clearly one of those groups," said Spribille. "This ecosystem is clearly very old and very diverse for some species groups. Each island and valley is different. As ecosystems go, it is definitely one that I'd label 'handle with care.'"

Case management is an effective, collaborative, and cost-effective way to help frequent users of health care services integrate all aspects of their care. The research team behind this study developed a program theory to investigate how, and in what circumstances, case management in primary care works to improve outcomes among frequent users who have chronic conditions.

The researchers note that their study only looks at case management in primary care for frequent users of health care, rather than case management use more generally. They also note that further research is still required to examine if the care setting or the professional role of case managers, such as nurses and social workers, may have an influence on the development of the patient-case manager relationship.

Trained dogs can detect fire accelerants such as gasoline in quantities as small as one billionth of a teaspoon, according to new research by University of Alberta chemists. The study provides the lowest estimate of the limit of sensitivity of dogs' noses and has implications for arson investigations.

"During an arson investigation, a dog may be used to identify debris that contains traces of ignitable liquids--which could support a hypothesis that a fire was the result of arson," explained Robin Abel, graduate student in the Department of Chemistry and lead author of the study. "Of course, a dog cannot give testimony in court, so debris from where the dog indicated must be taken back to the laboratory and analyzed. This estimate provides a target for forensic labs when processing evidence flagged by detection dogs at sites of potential arson."

The study involved two dog-and-handler teams. The first was trained to detect a variety of ignitable liquids, while the other was trained primarily with gasoline. Results show that the dog trained on a variety of liquids performed well detecting all accelerants, while the dog trained on gasoline was not able to generalize to other accelerants at extremely low concentrations.

Another outcome of the study was the development of a protocol that can be used to generate suitable ultra-clean substrates necessary for assessing the performance of accelerant-detection dogs for trace-level detection.

"In this field, it is well-known that dogs are more sensitive than conventional laboratory tests," said James Harynuk, associate professor of chemistry and Abel's supervisor. "There have been many cases where a dog will flag debris that then tests negative in the lab. In order for us to improve laboratory techniques so that they can match the performance of the dogs, we must first assess the dogs. This work gives us a very challenging target to meet for our laboratory methods."

So, just how small a volume of gasoline can a dog detect?

"The dogs in this study were able to detect down to one billionth of a teaspoon--or 5 pL--of gasoline," added Harynuk. "Their noses are incredibly sensitive."

DURHAM, N.C. - Engineers at Duke University have shown that nanosized silver cubes can make diagnostic tests that rely on fluorescence easier to read by making them more than 150 times brighter. Combined with an emerging point-of-care diagnostic platform already shown capable of detecting small traces of viruses and other biomarkers, the approach could allow such tests to become much cheaper and more widespread.

The results appeared online on May 6 in the journal Nano Letters.

Plasmonics is a scientific field that traps energy in a feedback loop called a plasmon onto the surface of silver nanocubes. When fluorescent molecules are sandwiched between one of these nanocubes and a metal surface, the interaction between their electromagnetic fields causes the molecules to emit light much more vigorously. Maiken Mikkelsen, the James N. and Elizabeth H. Barton Associate Professor of Electrical and Computer Engineering at Duke, has been working with her laboratory at Duke to create new types of hyperspectral cameras and superfast optical signals using plasmonics for nearly a decade.

At the same time, researchers in the laboratory of Ashutosh Chilkoti, the Alan L. Kaganov Distinguished Professor of Biomedical Engineering, have been working on a self-contained, point-of-care diagnostic test that can pick out trace amounts of specific biomarkers from biomedical fluids such as blood. But because the tests rely on fluorescent markers to indicate the presence of the biomarkers, seeing the faint light of a barely positive test requires expensive and bulky equipment.

"Our research has already shown that plasmonics can enhance the brightness of fluorescent molecules tens of thousands of times over," said Mikkelsen. "Using it to enhance diagnostic assays that are limited by their fluorescence was clearly a very exciting idea."

"There are not a lot of examples of people using plasmon-enhanced fluorescence for point-of-care diagnostics, and the few that exist have not been yet implemented into clinical practice," added Daria Semeniak, a graduate student in Chilkoti's laboratory. "It's taken us a couple of years, but we think we've developed a system that can work."

In the new paper, researchers from the Chilkoti lab build their super-sensitive diagnostic platform called the D4 Assay onto a thin film of gold, the preferred yin to the plasmonic silver nanocube's yang. The platform starts with a thin layer of polymer brush coating, which stops anything from sticking to the gold surface that the researchers don't want to stick there. The researchers then use an ink-jet printer to attach two groups of molecules tailored to latch on to the biomarker that the test is trying to detect. One set is attached permanently to the gold surface and catches one part of the biomarker. The other is washed off of the surface once the test begins, attaches itself to another piece of the biomarker, and flashes light to indicate it's found its target.

After several minutes pass to allow the reactions to occur, the rest of the sample is washed away, leaving behind only the molecules that have managed to find their biomarker matches, floating like fluorescent beacons tethered to a golden floor.

"The real significance of the assay is the polymer brush coating," said Chilkoti. "The polymer brush allows us to store all of the tools we need on the chip while maintaining a simple design."

While the D4 Assay is very good at grabbing small traces of specific biomarkers, if there are only trace amounts, the fluorescent beacons can be difficult to see. The challenge for Mikkelsen and her colleagues was to place their plasmonic silver nanocubes above the beacons in such a way that they supercharged the beacons' fluorescence.

But as is usually the case, this was easier said than done.

"The distance between the silver nanocubes and the gold film dictates how much brighter the fluorescent molecule becomes," said Daniela Cruz, a graduate student working in Mikkelsen's laboratory. "Our challenge was to make the polymer brush coating thick enough to capture the biomarkers--and only the biomarkers of interest--but thin enough to still enhance the diagnostic lights."

The researchers attempted two approaches to solve this Goldilocks riddle. They first added an electrostatic layer that binds to the detector molecules that carry the fluorescent proteins, creating a sort of "second floor" that the silver nanocubes could sit on top of. They also tried functionalizing the silver nanocubes so that they would stick directly to individual detector molecules on a one-on-one basis.

While both approaches succeeded in boosting the amount of light coming from the beacons, the former showed the best improvement, increasing its fluorescence by more than 150 times. However, this method also requires an extra step of creating a "second floor," which adds another hurdle to engineering a way to make this work on a commercial point-of-care diagnostic rather than only in a laboratory. And while the fluorescence didn't improve as much in the second approach, the test's accuracy did.

"Building microfluidic lab-on-a-chip devices through either approach would take time and resources, but they're both doable in theory," said Cassio Fontes, a graduate student in the Chilkoti laboratory. "That's what the D4 Assay is moving toward."

And the project is moving forward. Earlier in the year, the researchers used preliminary results from this research to secure a five-year, $3.4 million R01 research award from the National Heart, Lung, and Blood Institute. The collaborators will be working to optimize these fluorescence enhancements while integrating wells, microfluidic channels and other low-cost solutions into a single-step diagnostic device that can run through all of these steps automatically and be read by a common smartphone camera in a low-cost device.

"One of the big challenges in point-of-care tests is the ability to read out results, which usually requires very expensive detectors," said Mikkelsen. "That's a major roadblock to having disposable tests to allow patients to monitor chronic diseases at home or for use in low-resource settings. We see this technology not only as a way to get around that bottleneck, but also as a way to enhance the accuracy and threshold of these diagnostic devices."

Scientists from USC and the IFOM Cancer Institute in Milan have found that a fasting-mimicking diet could be more effective at treating some types of cancer when combined with vitamin C.

In studies on mice, researchers found that the combination delayed tumor progression in multiple mouse models of colorectal cancer; in some mice, it caused disease regression. The results were published in the journal Nature Communications.

"For the first time, we have demonstrated how a completely non-toxic intervention can effectively treat an aggressive cancer," said Valter Longo, the study senior author and the director of the USC Longevity Institute at the USC Leonard Davis School of Gerontology and professor of biological sciences at the USC Dornsife College of Letters, Arts and Sciences. "We have taken two treatments that are studied extensively as interventions to delay aging-- a fasting-mimicking diet and vitamin C -- and combined them as a powerful treatment for cancer."

The researchers said that while fasting remains a challenging option for cancer patients, a safer, more feasible option is a low-calorie, plant-based diet that causes cells to respond as if the body were fasting. Their findings suggest that a low-toxicity treatment of fasting-mimicking diet plus vitamin C has the potential to replace more toxic treatments.

Results of prior research on the cancer-fighting potential of vitamin C have been mixed. Recent studies, though, are beginning to show some efficacy, especially in combination with chemotherapy. In this new study, the research team wanted to find out whether a fasting-mimicking diet could enhance the high-dose vitamin C tumor-fighting action by creating an environment that would be unsustainable for cancer cells but still safe for normal cells.

"Our first in vitro experiment showed remarkable effects," said Longo. "When used alone, fasting-mimicking diet or vitamin C alone reduced cancer cell growth and caused a minor increase in cancer cell death. But when used together, they had a dramatic effect, killing almost all cancerous cells."

Longo and his colleagues detected this strong effect only in cancer cells that had a mutation that is regarded as one of the most challenging targets in cancer research. These mutations in the KRAS gene signal the body is resisting most cancer-fighting treatments, and they reduce a patient's survival rate. KRAS mutations occur in approximately a quarter of all human cancers and are estimated to occur in up to half of all colorectal cancers.

The study also provided clues about why previous studies of vitamin C as a potential anticancer therapy showed limited efficacy. By itself, a vitamin C treatment appears to trigger the KRAS-mutated cells to protect cancer cells by increasing levels of ferritin, a protein that binds iron. But by reducing levels of ferritin, the scientists managed to increase vitamin C's toxicity for the cancer cells. Amid this finding, the scientists also discovered that colorectal cancer patients with high levels of the iron-binding protein have a lower chance of survival.

"In this study, we observed how fasting-mimicking diet cycles are able to increase the effect of pharmacological doses of vitamin C against KRAS-mutated cancers," said Maira Di Tano, a study co-author at the IFOM, FIRC Institute of Molecular Oncology in Milan, Italy. "This occurs through the regulation of the levels of iron and of the molecular mechanisms involved in oxidative stress. The results particularly pointed to a gene that regulates iron levels: heme-oxygenase-1."

The research team's prior studies showed that fasting and a fasting-mimicking diet slow cancer's progression and make chemotherapy more effective in tumor cells, while protecting normal cells from chemotherapy-associated side effects. The combination enhances the immune system's anti-tumor response in breast cancer and melanoma mouse models.

The scientists believe cancer will eventually be treated with low-toxicity drugs in a manner similar to how antibiotics are used to treat infections that kill particular bacteria, but which can be substituted by other drugs if the first is not effective.

To move toward that goal, they say they needed to first test two hypotheses: that their non-toxic combination interventions would work in mice, and that it would look promising for human clinical trials. In this new study, they said that they've demonstrated both. At least five clinical trials, including one at USC on breast cancer and prostate cancer patients, are now investigating the effects of the fasting-mimicking diets in combination with different cancer-fighting drugs.

A low-pressure area that formed in the Northwestern Pacific Ocean several days ago has consolidated and organized into a tropical storm. NASA's Aqua satellite provided forecasters with a visible image of newly formed Tropical Storm Vongfong.

Vongfong, known locally as Ambo in the Philippines, threatens that country, according to the forecasts from the Joint Typhoon Warning Center or JTWC. The storm is also the first of tropical cyclone of the Northwestern Pacific Ocean typhoon season.

On May 12, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite provided a visible image of Vongfong that showed the storm had a more rounded shape than it did the previous day, as it continued to consolidate. A more rounded shape in a tropical cyclone indicates it is becoming a more organized storm. Infrared satellite imagery also indicated cooling cloud top temperatures, which means that cloud tops are extending higher into the troposphere. The higher the cloud top, the stronger the uplift of air in a storm, and usually, the stronger the storm.

At 11 a.m. EDT (1500 UTC) on May 12, the JTWC noted that Vongfong had maximum sustained winds near 35 knots (40 mph/65 kph) with higher gusts. It was located near latitude 11.4 degrees north and longitude 128.8 degrees east, about 495 miles east-southeast of Manila, Philippines. Vongfong was moving to the north-northwest.

JTWC forecasters expect Vongfong (Ambo) will move west-northwest, and then later northwest before finally turning to the north. The storm is expected to strengthen to typhoon force with maximum sustained winds near 65 knots (75 mph/120 kph) as it passes over the Philippines archipelago.

PAGASA, Philippine Atmospheric, Geophysical and Astronomical Services Administration, the entity that issues forecasts and warnings for the country noted, "Between tonight and tomorrow (13 May) evening, Ambo (Vongfong) will bring scattered light to moderate with at times heavy rain showers during thunderstorms over Mindanao and Eastern Visayas. Between tomorrow evening and Thursday (14 May) evening, Ambo (Vongfong) will bring moderate to heavy rains over Eastern Visayas, Catanduanes, Albay, Sorsogon, and Masbate. Tropical Cyclone Wind Signal (TCWS) #1 may be raised over Eastern Samar and the eastern portion of Northern Samar in the next 6 to 12 hours in anticipation of strong winds associated with the approaching tropical storm."

NASA's Aqua satellite is one in a fleet of NASA satellites that provide data for hurricane research.

Tropical cyclones/hurricanes are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For additional forecasts and updates from PAGASA, visit: http://bagong.pagasa.dost.gov.ph/

Immune system cells in the blood of breast cancer patients undergo alterations early in the disease course, according to a study published in the journal Clinical & Translational Immunology.

The authors believe that this discovery may contribute to the early identification of aggressive tumors and help enhance personalized immunotherapy strategies in the future.

The study was conducted while Rodrigo Nalio Ramos was doing a doctoral research internship at Claude Bernard University in Lyon, France, with a scholarship from São Paulo Research Foundation - FAPESP. The principal investigator was Jose Alexandre Marzagão Barbuto, a professor at the University of São Paulo's Biomedical Sciences Institute (ICB-USP), and the supervisor abroad was Christophe Caux, a senior scientist at the Lyon Cancer Research Center (CRCL).

"It's probable that monocytes, a type of leukocyte, can be used as a 'thermometer' of the disease. At least that's what we found for breast cancer patients," Ramos told.

Monocytes are the largest blood cells and account for approximately 7% of leukocytes. They are important immune cells, patrolling the body in search of potential threats such as viruses, bacteria and tumor cells. They are produced in the bone marrow and travel in the bloodstream to other tissues where they differentiate into macrophages (cells that engulf and destroy pathogens and apoptotic cells) or dendritic cells (cells that process antigen material and present it on the cell surface to the immune system structures that produce specific antibodies).

In this study, the researchers collected monocytes from the blood of breast cancer patients and tried to differentiate them in the laboratory into pro-inflammatory macrophages, which tell the immune system to send reinforcements to the tumor site. Monocytes were collected from 44 blood samples donated by breast cancer patients treated in France and at Pérola Byington Hospital in Brazil, as well as 25 samples from healthy individuals who served as controls.

"We used a cocktail of cytokines [signaling proteins that modulate the immune system] to try to induce monocytes to differentiate into pro-inflammatory macrophages. In theory, this type of cell is supposed to tell the organism it has a tumor and eliminate it," Ramos said. "However, the monocytes failed to perform this role in approximately 40% of the patients and displayed a very similar profile to that of the intratumoral macrophages associated with an adverse outcome."

The researchers then analyzed monocyte gene expression to determine which messenger RNAs the cells were producing. The analysis identified alterations to several signaling pathways, even in patients whose cells differentiated into macrophages like they should in healthy subjects.

"This confirms that breast cancer isn't just a local disease. It doesn't affect only the breast but affects all cells systemically. The defense cells are already altered when they enter the bloodstream," Barbuto told.

The researchers cannot yet explain exactly how these tumors interfere with the immune system. "One possibility is the secretion of transcription factors [proteins with a modulating function] into the blood," Ramos said, "another hypothesis could be a systemic effect via the bone marrow, but this is harder to verify. In this case, the disease could affect monocyte precursor cells."

According to Ramos, cancer can develop slowly over a period of years. "If we could detect monocyte alteration early on when there are no signs of the disease, it might be possible to prescribe more tests to determine if something is wrong," he said.