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Toronto - (January 13, 2020) Researchers at the Ontario Institute for Cancer Research (OICR) and the University Health Network (UHN) have discovered detailed new information about the subtypes of pancreatic cancer. A better understanding of the disease groups may lead to new treatment options and improved clinical outcomes for this lethal disease.

The study, published today in Nature Genetics, represents the most comprehensive analysis of the molecular subtypes of pancreatic cancer to date. Through detailed genomic and transcriptomic analyses, the research group identified five distinct subtypes of the disease (Basal-like-A, Basal-like-B, Classical-A, Classical-B, and Hybrid) with unique molecular properties that could be targeted with novel chemotherapies, biologics and immunotherapies.

"Therapy development for pancreatic cancer has been hindered by an incomplete knowledge of the molecular subtypes of this deadly disease," says lead author Dr. Faiyaz Notta, Co-Leader of OICR's Pancreatic Cancer Translational Research Initiative (PanCuRx) and Scientist at UHN's Princess Margaret Cancer Centre. "By rigorously analyzing advanced pancreatic cancers - which is the stage of disease that most patients have when they're diagnosed we were able to create a framework. This will help us develop better predictive models of disease progression that can assist in personalizing treatment decisions and lead to new targeted therapies."

The study is based on data from more than 300 patients with both early stage and advanced pancreatic cancer who participated in COMPASS, a first-of-its-kind clinical trial that is breaking new ground in discovery science and personalized pancreatic cancer treatment. COMPASS is enabled by advanced pathology laboratory techniques at UHN and OICR, and next generation sequencing at OICR.

"Most pancreatic cancer research is focused solely on early stage - or resectable - tumours, but in reality, pancreatic cancer is often found in patients after it has advanced and spread to other organs," says Notta. "COMPASS allowed us to look into these advanced cancers while treating these patients, develop a better understanding of the biology behind metastatic pancreatic cancer, and shed light on the mechanisms driving disease progression."

Interestingly, the Basal-like-A subtype, which had been difficult to observe before this study, was linked with a specific genetic abnormality. Most of the Basal-like-A tumours harboured several copies of a mutated KRAS gene, also known as a genetic amplification of mutant KRAS. The research group hypothesizes that some of the subtypes arise from specific genetic changes that occur as pancreatic cancer develops.

"This research opens new doors for therapeutic development," says Dr. Steven Gallinger, Co-Leader of OICR's PanCuRx, Surgical Oncologist at UHN and Senior Investigator, Lunenfeld Tanenbaum Research Institute at Mount Sinai Hospital. "We look forward to capitalizing on the promise of these discoveries, building on our understanding of pancreatic cancer subtypes, and bringing new treatments to patients with the disease."

New research has found that two factors - an outdoor location and the presence of a weapon - have a significant bearing on the verdict of juries in cases of child stranger rape.

The study, the first of its kind to focus on real jury verdicts in cases of child stranger rape in England and Wales, was led by Criminal Psychologist Dr Samantha Lundrigan, of Anglia Ruskin University (ARU), and the findings have been published in the journal Child Abuse and Neglect.

The researchers explored the factors that predict juries' decisions to convict or acquit in 70 cases of child stranger rape in London between 2001-15. By better understanding exactly what can influence jury verdicts - 19 different factors relating to the child, the accused and the offense were examined - it is hoped to improve the chances of guilty defendants being convicted in future cases.

The study found that verdicts were predicted by two offense-related factors. The presence of a weapon increased the odds of conviction by 412% and an outdoor location increased the odds by 360%.

No evidence was found that indicated that factors relating to either the victim or the perpetrator, such as age and ethnicity, influenced jury verdicts. Furthermore, neither a delay in a child's report nor a child's use of alcohol or drugs appeared to affect the chances of securing a conviction.

The researchers believe that a possible explanation for the significant influence of the two offense-related factors is that juries in these cases might have held stereotypical beliefs about the most likely circumstances of stranger rape - commonly known as the "real" rape stereotype.

Dr Lundrigan, Director of the Policing Institute for the Eastern Region (PIER) at Anglia Ruskin University, said: "Researchers have proposed the existence of a 'real' rape stereotype that describes an offense where an attack takes place in an outdoors location by an unknown perpetrator, often with a weapon.

"It is argued that rape cases most closely corresponding to this stereotype are more likely to result in conviction, whereas cases that deviate from the 'real' rape stereotype are less likely to be convicted. This argument is typically applied to rape involving adult victims but our study suggests there may be evidence of the stereotype also being applied in cases involving child victims.

"Our findings have potential implications for prosecution case building and courtroom policy. We show that in arriving at a verdict, juries may focus less on the characteristics of the victim and defendant, and more on the characteristics of the offense.

"Therefore, prosecutors could gather and present as much information as possible about the factors found to be of importance to juries and pay less attention to factors of lesser importance, such as the victim's behaviour, which can also help reduce distress for victims.

"The findings also have potential implications for courtroom policy. Specifically, it may be necessary for judges to warn juries about incorrect beliefs and stereotypes. Disparities in court outcome for different types of rape suggest that some victims are less likely to receive justice than others. It should not be assumed that stranger rape trials involving children are immune to the effect of stereotypical, pre-conceived beliefs about what happens in a rape."

New Rochelle, NY, January 13, 2020--Researchers are using caffeine to study how the brain processes information, and a new study shows the effectiveness of this approach. A placebo-controlled study in adults, which uses a simple Go/NoGo task, is published in Journal of Caffeine and Adenosine Research, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. Click here to read the full-text article free on the Journal of Caffeine and Adenosine Research website until February 15, 2020.

The article entitled "Caffeine as a Tool to Explore Active Cognitive Processing Stages in Two-Choice Tasks" was coauthored by Robert Barry, Jack Fogarty, and Frances De Blasio , University of Wollongong, Australia. In the cross-over study, one group of adults was given 250 mg of caffeine before completing a Go/NoGo task, in which they heard one of two tones. If they heard the "Go" target tone, they were to push a button. If they heard the "NoGo" tone they had to process that information and not push the button. The researchers used electroencephalography to measure event-related potential components and explore sequential processing in the individuals with and without caffeine. The study produced a number of novel outcomes, showing caffeine to be a useful tool

"A particularly significant finding of this study, performed in adults, is the qualitatively different effect of caffeine during the processing of a Go/NoGo task as compared to the results of a previous study by the same research group in children, providing new clues about the different cognitive strategies used by adults and children and their dependence on the adenosine system," says Journal of Caffeine and Adenosine Research Editor-in-Chief Sergi Ferré, MD, PhD, Chief of the Integrative Neurobiology Section at the National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD.

A minimally invasive procedure to treat a common foot and ankle disorder can reduce pain, recovery time, and postsurgery complications while improving functional outcomes, according to a report published in the journal Foot and Ankle Surgery.

The procedure treats insertional Achilles tendinopathy, a common and chronic orthopedic disorder in which patients experience pain at the Achilles tendon. The chronic degenerative condition can be particularly painful for athletes who perform push-off activities, such as basketball and soccer players.

The key-hole procedure, known as percutaneous Zadek osteotomy (ZO), can significantly decrease pain and provide a patient with relief in as little as six weeks after this technique compared to 23 weeks for recovery after the traditional open surgery.

"The traditional surgery requires larger incisions and inevitably carries a higher rate of infection, while this minimally invasive procedure has a low infection rate and less risk of tissue damage, helping to better preserve the tendon--and achieve a faster recovery and rehabilitation for the patient," said Ettore Vulcano, MD, Assistant Professor of Orthopedics at the Icahn School of Medicine at Mount Sinai, an orthopedic surgeon at Mount Sinai West, and co-author of the report, which was published online on November 20. "As a result of cutting-edge technology and the latest techniques at Mount Sinai, patients experience much less pain and improved function at a quicker rate. Even athletes can resume previous levels of sports activity at a much quicker rate compared to the traditional surgery."

Dr. Vulcano--one of a few doctors in the nation to revolutionize the minimally invasive approach--said the procedure includes making two very small incisions in the heel and removing a 5mm wedge of bone, which alters the orientation of the tendon fibers and is believed to decrease stress across the tendon.

The short recovery period includes protecting the foot in a splint or walker boot for two weeks, then resuming weight bearing while wearing a removable walker boot for an additional four weeks. Physical therapy can also begin two weeks after surgery. Patients are allowed to return to shoes six weeks after the outpatient procedure.

To watch our surgeon explain this procedure click here.

Chestnut Hill, Mass. - An international team of physicists, materials scientists, and mechanical engineers has confirmed the high thermal conductivity predicted in isotopically enriched cubic boron nitride, the researchers report in the advance electronic edition of the journal Science.

The thermal conductivity of a material conveys how much heat can pass through it when its ends are at different temperatures. Materials with very high thermal conductivity have important technological applications, such as cooling microelectronics. But very few of them have been discovered.

Theoreticians had predicted that isotopically pure cubic boron nitride (c-BN), should have extremely high thermal conductivity - second only to crystals made out of carbon, such as diamond.

"We wanted to determine whether high quality c-BN can in fact be made to observe the large thermal conductivity magnitudes in c-BN, and whether the huge increase in thermal conductivity with isotopic purification predicted from theoretical calculations is measured in the real material," said Boston College Professor of Physics David Broido, a co-author of the report.

c-BN is particularly challenging to make. Also, it is difficult to measure the thermal conductivity accurately when the value is high. The team overcame these challenges, and the measured thermal conductivity values for the c-BN samples were quite close to the ones they had calculated.

"The study confirms c-BN as one of only a handful of ultrahigh thermal conductivity materials, and shows it to have the largest increase in its thermal conductivity upon isotopic enrichment ever observed," Broido said.

The team also studied the related compounds, boron phosphide (BP) and boron arsenide (BAs). Most elements in nature have mixtures of isotopes, Broido explained. For example, naturally occurring boron has two isotopes, approximately 20 percent boron-10 and 80 percent boron-11. These different isotopes throughout the material produce disorder that adds to the thermal resistance. By making the material with only one isotope (either just B-10 or just B-11) through isotopic enrichment, this resistance is reduced so the thermal conductivity increases, he said.

By a remarkable coincidence of nature, the elements nitrogen, phosphorus and arsenic, which naturally bond with boron to make c-BN, BP and BAs, have only a single isotope. So, for these compounds the isotopic disorder is only on the boron atoms and thus is the same in all three compounds made with naturally occurring boron, Broido said. Yet, isotopic enrichment of the boron atoms gave a doubling of thermal conductivity for c-BN, but much smaller increases for BP and BAs.

The boron and nitrogen atoms have roughly the same mass, while arsenic and phosphorous are heavier.

"We showed that the larger arsenic and phosphorous masses compared with boron caused the isotopic disorder in BAs and BP to give only small resistance to heat flow," said Broido, who performed theoretical calculations with Boston College post-doctoral fellow Navaneetha K. Ravichandran. "It is as if the isotopic disorder becomes invisible to the heat flowing through the BAs and BP samples."

In contrast, removing the same amount of disorder through isotopic enrichment in c-BN results in a huge increase in thermal conductivity.

In all, 24 researchers contributed to the project. In addition to Boston College, the team included the research groups of Gang Chen at MIT, David Cahill at the University of Illinois, Urbana-Champaign, Li Shi at the University of Texas in Austin, Bing Lv at University of Texas in Dallas, Zhifeng Ren at the University of Houston, and Takashi Taniguchi at Japan's National Institute for Materials Science.

"It was amazing to see the measured data and theoretical calculations consistently agreeing so closely with each other. The theory has no parameters in it that can be adjusted to fit the measurements. It either agrees with the measurements or it doesn't," said Broido. "The excellent agreement highlights the accuracy of the theory, the precision of the measurements, and the high purity of the samples."

Broido said further investigation is needed to better understand the types of defects that occur in c-BN that act to reduce its heat conductivity. Because such ultrahigh thermal conductivity materials are so rare, he hopes that theoretical and computational searches can identify new candidates and unravel the mysteries surrounding their usual properties.

Humans control their behavior in numerous ways, from stopping the urge pick at a scab to resisting the impulse to eat an entire box of chocolates. Suppressing undesired behavior, referred to as "cognitive control," traditionally has been linked to the functioning of the dorsal anterior cingulate cortex (dACC) in the front of the brain. Activity in dACC is observed across a variety of contexts, yet its function remains intensely debated in the field of cognitive neuroscience.

Theories of the role of dACC in inhibitory control highlight surprise, choice difficulty and value of control as key mechanisms. Although these theories have been successful in explaining dACC involvement in inhibitory control, it remains unclear whether these mechanisms generalize to motivated control. Motivated control processes help people achieve a desired goal even when doing so is difficult or costly.

A study led by a neuroscientist at Florida Atlantic University in collaboration with Radboud University, Nijmegen, the Netherlands, and Ghent University, Ghent, Belgium, sought to better understand how motivational control processes help maximize performance when faced with task challenges. Using functional magnetic resonance imaging (fMRI), researchers tested three prominent theories of cognitive control (predicted response outcome or PRO, expected value of control or EVC and choice difficulty or CD) using a speeded value-based decision-making task.

To differentiate among these theories, researchers developed a set of empirical predictions for what activation in the dACC should resemble if the theory was correct. By placing these theories in opposition within the same experiment, the researchers were able to develop a series of analyses to distinguish among the theories' competing predictions.

Results of the study, published in the journal Nature Human Behavior, demonstrate how a singular model unifies conflicting findings on dACC function, takes cognitive control research to new heights, and provides fascinating insights into the role of dACC as a component of a network of brain regions that support motivated behavior.

Researchers discovered that the single mechanism of surprise - defined in the paper as the difference between events that are expected to happen versus those that actually happen - best accounts for activity in dACC during a task requiring motivated control. The series of analyses they performed indisputably supported the PRO model - indicating that recognizing surprising events could provide a unified explanation for dACC function. Surprise signaling is the shared driver of inhibitory and motivated control and supports surprise coding as the core mechanism underlying medial prefrontal cortex function more generally, with the source of the surprise determining the exact neural population implicated.

"During motivated control, we found that dACC activity reflects the calculation of surprise and does not track choice difficulty or value," said William Alexander, Ph.D., corresponding author and an assistant professor of psychology and a member of the Center for Complex Systems and Brain Sciences in FAU's Charles E. Schmidt College of Science. "Instead, dACC activity is all about predictions of our choices and environment and especially signals when those predictions are wrong. A key contributor to motivated control, dACC tracks a computational quantity similar to surprise, which is generated when events differ from our expectations."

For the study, researchers dissociated the need to invigorate a response from reward incentive to distinguish motivated control from value-driven responding. fMRI data recorded human subjects performing various tasks ranging from easy to difficult. Participants within an fMRI experiment chose between two options each tied to a different amount of money and had to make choices very quickly, within a 750ms timeframe. This time pressure required them to exert cognitive control to balance the competing demands of the task, an assumption that was confirmed through their behavioral results.

Another key finding of the study is that several other regions of the brain in addition to the dACC also generated the patterns of activity predicted by the PRO model. Future studies will need to position dACC within a larger network of brain regions that collectively evaluate the need for increased control of behavior and then implement that control through changes in other systems.

In birds, timing of arrival in a breeding area influences who ends up breeding and who does not. This aspect of behaviour, well-known in migratory birds, has now been studied for the first time in a non-migratory species, the blue tit. Researchers at the Max Planck Institute for Ornithology in Germany found that arrival time in the breeding area was an individual-specific and fitness-relevant trait for this resident bird species, as early-arriving individuals were more likely to breed in that year. The study suggests that it might be worthwhile to consider migration on different scales, not only as movements over thousands of kilometres to wintering grounds, but also more generally as movements between breeding and non-breeding sites.

For migratory birds, early arrival in spring in the breeding area increases the likelihood of getting a mate and/or a high-quality territory, and therefore increases breeding success. However, early-arriving birds may face harsher environmental conditions that might offset the benefits, as they lead to a higher mortality risk. For non-migratory or year-round resident species, the timing of arrival in the breeding area and its effect on reproductive success has not been considered previously, perhaps because it is assumed that most individuals stay in the local area also during the non-breeding season.

The blue tit is a partial migrant in the northern part of its range but is considered to be non-migratory in the rest of Europe. In a study site in Southern Germany, researchers from the Max Planck Institute for Ornithology installed a self-designed, custom-built automated monitoring system that registered all visiting blue tits throughout the year. Individuals could be "followed" because they carried a "Passive Integrated Transponder" (PIT-tag). The PIT tag is a tiny tag with an individual code that is activated externally by a scanning device present in 16 feeders and all 277 nest boxes in the study area. With this setup, the researchers could record the date, time, and identity of every PIT-tagged blue tit visit and thus estimate the arrival date of all adult individuals in the study site.

Resident and migratory individuals

After breeding ended in June, blue tits stopped visiting the nestboxes for several months. Many individuals were first registered again either at a feeder or at a nestbox between August and October. Another arrival peak occurred from January to March. "The data suggest that some individuals may have been true residents, staying in the study site during winter, while others left the area during the non-breeding season", says Carol Gilsenan, first author of the study.

Although arrival dates were highly variable between individuals - spanning roughly eight months -, the researchers were surprised to find that the same individuals arrived around the same time each year. Generally, males arrived earlier in the breeding area than females, and birds that bred together arrived around the same time in the study site.

Impatient partners

However, a previous study of the research group showed that blue tits did not patiently wait for their mate from last year to return: if the former partner did not arrive within about a week after their own arrival, the probability of divorce strongly increased. "In a short-lived species such as the blue tit, individuals that would decide to wait for their former partner to return may risk not breeding at all," explains Gilsenan.

The researchers found that early-arriving individuals had a higher chance to breed and that the timing of arrival predicted several aspects of the birds' breeding success. How far the blue tits went outside the study site and where they stayed during the winter months remains unclear, but Bart Kempenaers, lead author of the study, is convinced: "Our study suggests that many if not most blue tits are leaving the breeding area during the non-breeding season despite being referred to as resident. Migrants and non-migrants may then differ mostly in how far they move." Whether studying the seasonal movements of individuals of non-migratory species will further break up the dichotomy between "resident" and "migratory" species remains to be seen.

New Rochelle, NY, January 13, 2020--An in-depth look at the science of glycobiology and glycan diagnostics, and their promise in personalized medicine in the current post-genomic era are featured in a special issue of OMICS: A Journal of Integrative Biology, the peer-reviewed interdisciplinary journal published by Mary Ann Liebert, Inc., publishers. Click here to read the special issue on Glycomics and Personalized Glycomedicine free on the OMICS: A Journal of Integrative Biology website until February 15, 2020.

This special issue was co-edited by Wei Wang, MD, PhD, Edith Cowan University (Joondalup, Australia) and Capital Medical University (Beijing, China), and Vural Özdemir, MD, PhD, Editor-in-Chief of OMICS: A Journal of Integrative Biology. Dr. Wang and a team of researchers from Australia, China, and Croatia contributed an article entitled "Type 2 Diabetes Mellitus is Associated with the Immunoglobulin G N-Glycome through Putative Proinflammatory Mechanisms in an Australian Population.") The team analyzed the N-glycan patterns of immunoglobulin G (IgG) in individuals with type 2 diabetes (T2D) and found novel associations between the IgG N-glycome, T2D, and clinical risk factors related to proinflammatory mechanisms. These IgG N-glycomic alterations offer promise as future biomarkers for T2D diagnosis or monitoring of progression to cardiovascular disease or renal failure.

A review article by Tanja Kunej, PhD University of Ljubljana (Domzale, Slovenia) is entitled "Rise of Systems Glycobiology and Personalized Glycomedicine: Why and How to Integrate Glycomics with Multiomics Science?" Dr. Kunej proposes that for glycomics to make a greater, systems-scale contribution to biology and medicine, it needs to transition from a single omics science to multiomics technology platforms. The article presents examples of glycomics in association with other omics fields, including genomics, transcriptomics, proteomics, metabolomics, and epigenomics, and discusses current knowledge gaps and suggests future research directions.

Vural Özdemir, MD, PhD, Editor-in-Chief of OMICS: A Journal of Integrative Biology states: "Carbohydrates and glycans matter for personalized medicine. This OMICS special issue on glycomics and personalized glycomedicine signals the rise of glyco-theranostics as a new specialty in diagnostic medicine and systems science. It connects the dots between some of the most critical issues in biomarkers, post-genomic personalized medicine, and emerging technology governance to move systems science into clinical practice. Any reader interested in diagnostics in health care should benefit from reading the new OMICS issue curated with a systems approach to glycobiology and personalized/precision medicine."

Tropical Storm Claudia is battling wind shear as it continues moving away from Western Australia and through the Southern Indian Ocean. NASA-NOAA's Suomi NPP satellite provided forecasters with an image of the storm on January 13.

Visible imagery from NASA satellites help forecasters understand if a storm is organizing or weakening. The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of Claudia that showed the storm appeared elongated.

The shape of a tropical cyclone provides forecasters with an idea of its organization and strength, and NASA-NOAA's Suomi NPP satellite provided a visible image of the landfall of the storm to forecasters. The storm appeared elongated from west to east. The imagery shows that Claudia is under strong vertical wind shear from the northwest to southeast. The low-level center now appears to the east of the main convection (rising air that creates the thunderstorms that make up the tropical cyclone).

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels.

At 7:43 a.m. EST (8:43 pm WST) on Monday, January 13, 2020 the Australian Government Bureau of Meteorology (ABM) noted that "Severe Tropical Cyclone Claudia (Category 3) was located latitude 17.3 degrees south and longitude 114.1 east, about 298 miles (480 km) northwest of Karratha and 320 miles (515 km) north of Exmouth. Claudia is moving west-southwest at 18 miles (29 kilometers) per hour. Maximum sustained winds were near 80 knots (92 mph/148 kph)."

Claudia is expected to continue to track towards the west-southwest and remain over open waters, well north of the Pilbara.

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.

By Rob Gutro
NASA's Goddard Space Flight Center

A modern airplane's fuselage is made from multiple sheets of different composite materials, like so many layers in a phyllo-dough pastry. Once these layers are stacked and molded into the shape of a fuselage, the structures are wheeled into warehouse-sized ovens and autoclaves, where the layers fuse together to form a resilient, aerodynamic shell.

Now MIT engineers have developed a method to produce aerospace-grade composites without the enormous ovens and pressure vessels. The technique may help to speed up the manufacturing of airplanes and other large, high-performance composite structures, such as blades for wind turbines.

The researchers detail their new method in a paper published today in the journal Advanced Materials Interfaces.

"If you're making a primary structure like a fuselage or wing, you need to build a pressure vessel, or autoclave, the size of a two- or three-story building, which itself requires time and money to pressurize," says Brian Wardle, professor of aeronautics and astronautics at MIT. "These things are massive pieces of infrastructure. Now we can make primary structure materials without autoclave pressure, so we can get rid of all that infrastructure."

Wardle's co-authors on the paper are lead author and MIT postdoc Jeonyoo Lee, and Seth Kessler of Metis Design Corporation, an aerospace structural health monitoring company based in Boston.

Out of the oven, into a blanket

In 2015, Lee led the team, along with another member of Wardle's lab, in creating a method to make aerospace-grade composites without requiring an oven to fuse the materials together. Instead of placing layers of material inside an oven to cure, the researchers essentially wrapped them in an ultrathin film of carbon nanotubes (CNTs). When they applied an electric current to the film, the CNTs, like a nanoscale electric blanket, quickly generated heat, causing the materials within to cure and fuse together.

With this out-of-oven, or OoO, technique, the team was able to produce composites as strong as the materials made in conventional airplane manufacturing ovens, using only 1 percent of the energy.

The researchers next looked for ways to make high-performance composites without the use of large, high-pressure autoclaves -- building-sized vessels that generate high enough pressures to press materials together, squeezing out any voids, or air pockets, at their interface.

"There's microscopic surface roughness on each ply of a material, and when you put two plys together, air gets trapped between the rough areas, which is the primary source of voids and weakness in a composite," Wardle says. "An autoclave can push those voids to the edges and get rid of them."

Researchers including Wardle's group have explored "out-of-autoclave," or OoA, techniques to manufacture composites without using the huge machines. But most of these techniques have produced composites where nearly 1 percent of the material contains voids, which can compromise a material's strength and lifetime. In comparison, aerospace-grade composites made in autoclaves are of such high quality that any voids they contain are neglible and not easily measured.

"The problem with these OoA approaches is also that the materials have been specially formulated, and none are qualified for primary structures such as wings and fuselages," Wardle says. "They're making some inroads in secondary structures, such as flaps and doors, but they still get voids."

Straw pressure

Part of Wardle's work focuses on developing nanoporous networks -- ultrathin films made from aligned, microscopic material such as carbon nanotubes, that can be engineered with exceptional properties, including color, strength, and electrical capacity. The researchers wondered whether these nanoporous films could be used in place of giant autoclaves to squeeze out voids between two material layers, as unlikely as that may seem.

A thin film of carbon nanotubes is somewhat like a dense forest of trees, and the spaces between the trees can function like thin nanoscale tubes, or capillaries. A capillary such as a straw can generate pressure based on its geometry and its surface energy, or the material's ability to attract liquids or other materials.

The researchers proposed that if a thin film of carbon nanotubes were sandwiched between two materials, then, as the materials were heated and softened, the capillaries between the carbon nanotubes should have a surface energy and geometry such that they would draw the materials in toward each other, rather than leaving a void between them. Lee calculated that the capillary pressure should be larger than the pressure applied by the autoclaves.

The researchers tested their idea in the lab by growing films of vertically aligned carbon nanotubes using a technique they previously developed, then laying the films between layers of materials that are typically used in the autoclave-based manufacturing of primary aircraft structures. They wrapped the layers in a second film of carbon nanotubes, which they applied an electric current to to heat it up. They observed that as the materials heated and softened in response, they were pulled into the capillaries of the intermediate CNT film.

The resulting composite lacked voids, similar to aerospace-grade composites that are produced in an autoclave. The researchers subjected the composites to strength tests, attempting to push the layers apart, the idea being that voids, if present, would allow the layers to separate more easily.

"In these tests, we found that our out-of-autoclave composite was just as strong as the gold-standard autoclave process composite used for primary aerospace structures," Wardle says.

The team will next look for ways to scale up the pressure-generating CNT film. In their experiments, they worked with samples measuring several centimeters wide -- large enough to demonstrate that nanoporous networks can pressurize materials and prevent voids from forming. To make this process viable for manufacturing entire wings and fuselages, researchers will have to find ways to manufacture CNT and other nanoporous films at a much larger scale.

"There are ways to make really large blankets of this stuff, and there's continuous production of sheets, yarns, and rolls of material that can be incorporated in the process," Wardle says.

He plans also to explore different formulations of nanoporous films, engineering capillaries of varying surface energies and geometries, to be able to pressurize and bond other high-performance materials.

"Now we have this new material solution that can provide on-demand pressure where you need it," Wardle says. "Beyond airplanes, most of the composite production in the world is composite pipes, for water, gas, oil, all the things that go in and out of our lives. This could make making all those things, without the oven and autoclave infrastructure."

This research was supported, in part, by Airbus, ANSYS, Embraer, Lockheed Martin, Saab AB, Saertex, and Teijin Carbon America through MIT's Nano-Engineered Composite aerospace Structures (NECST) Consortium.

New research detects gamma-ray emissions at unusual energy levels (above 56 and even 100 tera electron Volts (TeV)). Scientists with the High Altitude Water Cherenkov (HAWC) Collaboration analyzed the galactic emissions by identifying their source, their location, and their spectral fit. They identified nine significant galactic emissions with energies higher than 56 TeV, three of which had energies over 100TeV. These high energy sources could indicate the presence of previously hypothesized extreme cosmic accelerators, known as PeVatrons (which push particles up to one peta electron Volt). The results also could benefit scientists looking for pulsars -- neutron stars that emit electromagnetic radiation -- and supernova remnants.

Evaporation can explain why water levels drop in a full swimming pool, but it also plays an important role in industrial processes ranging from cooling electronics to power generation. Much of the global electricity supply is generated by steam plants, which are driven by evaporation.

But determining when and how quickly a liquid will convert to a vapor has been stymied by questions about how - and how much - the temperature changes at the point where the liquid meets the vapor, a concept known as temperature discontinuity. Those questions have made it more difficult to create more efficient processes using evaporation, but now researchers from the University of Houston have reported answers to what happens at that interface, addressing 20 years of conflicting findings. The work was reported in the Journal of Physical Chemistry.

The temperature discontinuity was first reported in 1999 by Canadian researchers G. Fang and C.A. Ward, who noted that they were unable to explain the phenomenon through classical mechanics. The new work solves that mystery.

Hadi Ghasemi, Cullen Associate Professor of Mechanical Engineering at UH, said the new understanding eliminates the "bottleneck" that has complicated predictions and simulations of processes involving evaporation.

"We demonstrated the physics of what happens within the space of a few molecules at the interface and accurately developed a theory on the evaporation rate," Ghasemi said. "That allowed us to explain all of the conflicting findings that have been reported in the last 20 years and solve this mystery."

In addition to Ghasemi, co-authors for the paper included first author Parham Jafari, a PhD student at UH, and Amit Amritkar, a research assistant professor at UH.

The researchers first approached the question in the lab, but Ghasemi said they were unable to get the needed spatial resolution for a definitive answer. They used a computational approach in order to find the properties of liquid and vapor within the length of a few molecules.

The explanation - developed using the Direct Simulation Monte Carlo method - will allow scientists to more accurate simulate the performance of all systems based on the theory of evaporation.

"With this understanding, we can more accurately develop simulations of performance and efficiency, as well as design and predict the behavior of advanced systems," Ghasemi said.

That would have applications for energy, electronics, photonics and other fields.

As just one example of the importance of evaporation, Ghasemi noted that 80% of electric power globally is generated through steam plants, which work based on evaporation phenomena.

A male orchid bee zips around the rainforest, a flash of iridescent green against an equally emerald background. The bee stops at various flowers, fungi and dead trees, collecting fragrant particles and storing them in pockets in its hind legs. Then, it perches on a tree trunk. But the bee doesn't rest. Instead, it flitters about, using its wings to disperse a bouquet of perfumes into the air.

The aromatic efforts are all for the sake of attracting a mate.

"We know that many animals produce pheromones and they usually produce them through some metabolic pathway," said Associate Professor Santiago Ramirez, UC Davis Department of Evolution and Ecology. "But orchid bees are unique in that the majority of their pheromones are actually collected from plants and other sources like fungi."

Orchid bees are master perfumers, and research suggests that the perfumes males concoct are unique to their specific species. For years, Ramirez, a member of the UC Davis Center for Population Biology, and recent Ph.D. graduate student Philipp Brand, Population Biology Graduate Group, have studied orchid bee mating behaviors, unraveling the complex chemicals responsible for successful procreation. The research has given them an unprecedented view into the formation of new species. And the driver of divergence: environmental perfumes.

In a study appearing in Nature Communications, Brand, Ramirez and their colleagues link the evolution of sexual signaling in orchid bees to a gene that's been shaped by each species' perfume preferences.

"Our study supports the hypothesis that in the orchid bee perfume communication system, the male perfume chemistry and the female preference for the perfume chemistry can simultaneously evolve via changes in a single receptor gene," said Brand, whose thesis was the basis for the study.

"Imagine you have an ancestral species that uses certain compounds to communicate with each other," said Ramirez. "If you have a chemical communication channel and then that chemical communication channel splits into two separate channels, then you have the opportunity for the formation of two separate species."

A fragrant, front row seat to evolution

Of the 250 orchid bee species, Brand's and Ramirez's research focused on Euglossa viridissima and Euglossa dilemma, two separate species previously classified under a single scientific name. They diverged roughly 150,000 years ago. Physically and genetically, these two species are almost indistinguishable, but luckily, they primarily live in non-overlapping ranges in Central America and South America, with some overlap in Mexico's Yucatán Peninsula.

"This is a neat distribution for the study of species formation because it reveals that the variation we observed is not just the product of geographic variation, and when the two species coexist, they still remain as separate species, even though they experienced hybridization in the recent past," said Ramirez. "Each species is occupying a unique niche in chemical space."

E. viridissima and E. dilemma are actually easier to tell apart by the chemical differences of their perfumes. Using gas chromatography and mass spectrometry, the researchers separated and analyzed each chemical compound in a male orchid bee's enticing perfume. Between the perfumes of E. viridissima and E. dilemma, the difference came down to two molecules. E. viridissima's perfume contains a molecule called 2-hydroxy-6-nona-1,3-dienylbenzaldehyde (HNDB), and E. dilemma's contains a lactone called L97.

"We found the bees grouped into two clouds based on the presence of these major compounds, which strongly suggest that each of these corresponds to a separate species of orchid bee," said Ramirez.

According to Ramirez, this means that these pheromone-like perfumes aren't just different between the species but that they likely influenced their original divergence.

"It makes sense, right?" said Ramirez. "If you have a chemical signal that is different and therefore you're not going to mate with those who have a different signal, then that will help maintain species separate from each other."

Scent signals--follow your antennae

After analyzing the genomes of E. viridissima and E. dilemma, Ramirez and his colleagues highlighted differences in a cluster of olfaction-related genes. In orchid bees, these genes are expressed in their antennae, allowing them to detect airborne molecules. The researchers identified olfactory receptor gene 41 (OR41) as being different between the two species.

"That gene has accumulated a lot of changes between these two species, suggesting that those changes are responsible for the collection of different perfume compounds," said Ramirez. "The idea here is that as these olfactory genes evolve and accumulate new mutations, they're more sensitive to different molecules and therefore enable the bees to collect or not collect certain compounds."

According to Brand, such differences in a single gene is extremely rare. "Usually divergent genetic regions--also called 'genomic islands of divergence'--include tens to hundreds of genes and it is very hard to pinpoint the gene under selection," he said.

It's the bee's knees (or genes)

To figure out what molecules the two species of orchid bees detect using OR41, Brand and Ramirez used another airborne insect, the fruit fly (Drosophila melanogaster).

"We created these transgenic flies expressing orchid bee genes and it's an ideal setup for dissecting exactly what the function of this gene is," said Ramirez.

The team tested each species' variant OR41 against single odors and blends of odors commonly found in the orchid bees' environment.

When the team tested odors against E. viridissima's OR41 variant, they found it responded to perfume mixtures found in waxes used for brood cell construction by females and to "several medium to long-chain fatty-acids" common in waxes. The variant didn't respond to single compound odors.

E. dilemma's OR41 variant responded consistently to the species-specific HNDB compound and E. dilemma perfume mixtures containing HNDB.

"The OR41 variant in E. dilemma evolved to become a highly specific receptor responding exclusively to its major species-specific perfume compound," said Brand. "It is plausible that E. dilemma gained the ability to discriminate HNDB from other chemicals because of this."

Brand has continued exploring insect chemosensory systems as a postdoctoral researcher in the lab of Associate Professor Vanessa Ruta, of The Rockefeller University. He's working "to identify key genetic and neural mechanisms underlying the evolution of behavior."

"I am focusing on reproductive behaviors such as courtship and mating and how these evolve and contribute to the origin and maintenance of novel species," said Brand

"To me, fully integrating the traditionally separated fields of neurobiology and evolutionary biology is the next big step to learn how behaviors diverge and give rise to novel species," he added.

Ramirez has also established the first-ever breeding population of orchid bees at a research facility at the University of Florida's Ft. Lauderdale campus. Ramirez hopes to use the facility to continue studying bee behaviors and see if orchid bees are a viable option for in-depth research in chemical communication, animal behavior and pollination biology.

URBANA, Ill. - For corn growers, the decision of when and how much nitrogen fertilizer to apply is a perennial challenge. Scientists at the University of Illinois have shown that nanosatellites known as CubeSats can detect nitrogen stress early in the season, potentially giving farmers a chance to plan in-season nitrogen fertilizer applications and alleviate nutrient stress for crops.

"Using this technology, we can possibly see the nitrogen stress early on, before tasseling. That means farmers won't need to wait until the end of the season to see the impact of their nitrogen application decisions," says Kaiyu Guan, assistant professor in the Department of Natural Resources and Environmental Sciences at the University of Illinois, and Blue Waters professor at the National Center for Supercomputing Applications. He is also principal investigator on a new study published in IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing.

Being able to detect and address changes in crop nutrient status in real time is vitally important to avoid damage at critical periods and optimize yield. In general, existing satellite technology cannot achieve both high spatial resolution and high revisiting frequency (how often a given satellite comes back to the same spot above the Earth). Alternatively, drones can detect nutrient status in real time, but they usually can only cover local areas; thus, their utility is limited in scale.

CubeSats bridge the gap between existing satellite technology and drones. With more than 100 of the relatively tiny satellites currently in orbit, Guan says, "CubeSats from Planet get down to a 3-meter resolution and revisit the same location every few days. So, right now we can monitor crop nitrogen status in real time for a much broader area than drones."

Guan and his collaborators tested the capabilities of both drones and CubeSats to detect changes in corn chlorophyll content, a proxy for the plant's nitrogen status. The researchers focused on an experimental field in Central Illinois during the 2017 field season. Corn in the field was nitrogen-stressed to varying degrees due to multiple nitrogen application rates and timings, including all nitrogen applied at planting, and split applications at several developmental stages.

The analyzed field was one of several in a larger study looking at nitrogen rates and timing, set up by Emerson Nafziger, professor emeritus in the Department of Crop Sciences at Illinois and co-author on the study.

"The idea was to see how much effect timing and form of nitrogen fertilizer would have on yield. This study allows an evaluation of how well the imaging could capture yield responses to nitrogen applied at different rates and times," Nafziger says.

The scientists compared images from drones and CubeSats, and their signals matched well with tissue nitrogen measurements taken from leaves in the field on a weekly basis. Both technologies were able to detect changes in chlorophyll contents with a similar degree of accuracy and at the same point in the season.

"This information generates timely and actionable insights related to nitrogen stress, and so could provide guidance for additional nitrogen application where it's needed," Guan says.

The implications go beyond optimizing yield.

"The low cost of nitrogen fertilizer and high corn yield potential motivates farmers to apply extra nitrogen as 'insurance' against nitrogen deficiency that lowers yield. But applying more nitrogen than the crop requires is both a financial and environmental risk," says Yaping Cai, graduate student in Guan's research group and lead student author on the paper.

Guan adds, "A better tool for fertilizer use, enabled through new satellite technology and ecosystem modeling, could ultimately help farmers to reduce cost, increase yield, and meanwhile reduce environmental footprint for a sustainable agricultural landscape."

Severe droughts happened simultaneously in the regions that supply water to Southern California almost six times per century on average since 1500, according to new University of Arizona-led research.

The study is the first to document the duration and frequency of simultaneous droughts in Southern California's main water sources - the Sacramento River basin, the Upper Colorado River Basin and local Southern California basins.

The report highlights what a previous researcher dubbed "perfect droughts" - when the precipitation or streamflow in all three water sources falls below the median for two or more years. The most recent perfect drought lasted from 2012 to 2015.

Concurrent droughts lasting multiple years in all three sources of water for Southern California pose "the most serious challenge to water management," the authors write in the Journal of American Water Resources Association.

The researchers used the annual growth rings of trees to reconstruct the climate history of the three water sources back to the year 1126. For the period 1906 to 2017, the amount of annual precipitation and streamflow was recorded by instruments.

"Such a reconstruction of the water supply for Southern California has not been done before," said first author Connie Woodhouse, a professor in the School of Geography and Development.

The California Department of Water Resources, or CADWR, wanted to know the past frequency and duration of severe droughts in the major sources of Southern California's water supply and funded the study.

The team found perfect droughts were not unusual and were evenly distributed in time since about 1400, with about five to six such droughts per 100 years, Woodhouse said. More severe and longer-term droughts occurred during the warmer 11th and 12th centuries.

"California Department of Water Resources has a long history as a water resources department of using paleodata to help its understanding of drought," said co-author David Meko, a research professor of dendrochronology in the Laboratory of Tree-Ring Research.

Woodhouse and Meko's co-author is Erica Bigio, who was a member of the research team while at the University of Arizona and is now a lecturer at the University of Nevada, Reno.

The researchers also tested whether specific oceanic or atmospheric circulation patterns could be linked to the occurrence of perfect droughts. The only pattern they found was that perfect droughts coincided with high pressure off the northwest Pacific Coast that pushes storm tracks north of all three sources of water.

The team's paper, "A Long View of Southern California Water Supply: Perfect Droughts Revisited," is scheduled for publication XXXX DATE in the Journal of the American Water Resources Association.

Woodhouse and Meko previously studied droughts in the Sacramento River Basin and the Colorado River Basin for CADWR using tree rings to reconstruct streamflow patterns back to the 10th century or earlier. The agency asked the team to expand on previous studies to include water sources in Southern California.

Each annual growth ring of a tree reflects the growing conditions, including temperature and precipitation, during that year. By taking either pencil-thin cores from living trees or cross-sections of dead trees, scientists piece together the patterns of annual rings to reveal growing conditions going back centuries. The climate information in tree rings also reflects variations in streamflow, making it possible to develop reconstructions of past streamflow.

Groundwater is one of the water sources for Southern California. There are not enough historical instrumental records of groundwater records to develop a reconstruction going back centuries, so the team used precipitation as a proxy for groundwater.

To determine past precipitation for Southern California going back 890 years, Bigio led the team in collecting additional tree-ring records from mountain ranges including the San Bernardino, San Gabriel and San Jacinto mountains.

The team also checked whether perfect droughts coincided with specific atmospheric or oceanic conditions, which was a new approach, Meko said.

"The California Department of Water Resources wanted this long-term information to help with planning," he said. "The broader question is what causes these simultaneous droughts in these different basins."

The researchers found that no one atmospheric or oceanic circulation pattern, such as El Niño, corresponded with severe droughts in all three basins.

The team did find that perfect droughts occurred in Southern California when the storm tracks shifted north. Woodhouse said several different atmospheric circulation patterns can cause that shift.

Longer and more severe droughts in all three basins occurred in the 11th and 12th centuries, a time period when the climate was warmer, she said.

"We had a nine-year perfect drought and a seven-year perfect drought - and they were pretty much West-wide," Woodhouse said.

The researchers write in closing that, given the projected changes in water availability due to warming, "perfect droughts such as 2012-2015 may become increasingly common, with the potential for even longer events to occur."