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LOS ANGELES, Feb. 20, 2020 -- Treating stroke patients in specialized ambulances speeds treatment and reduces patients' disability, according to late breaking science presented today at the American Stroke Association's International Stroke Conference 2020. The conference, Feb. 19-21 in Los Angeles, is a world premier meeting for researchers and clinicians dedicated to the science of stroke and brain health.

The Berlin Prehospital Or Usual Delivery (B_PROUD) trial investigated if prehospital treatment in a mobile stroke unit could improve patient outcomes compared to usual care, which was emergency transportation in a conventional ambulance and in-hospital treatment. Patients (total 749, average age 73, 46% females) were assigned to treatment based on the availability of three mobile stroke units in the metropolitan area of Berlin, Germany, and compared with patients (total 794, average age 74, 48% females) who received conventional care.

Mobile stroke units are ambulances staffed with emergency medicine neurologists and equipped with a CT scanner and a lab designed to enable specific stroke treatment at the scene. Prehospital treatment consisted of administering medications to dissolve the clot blocking blood flow in or to the brain (ischemic stroke). Timing is key because the clot-busting medication alteplase should be administered within 4.5 hours of stroke symptoms.

Researchers found that:

60% of patients assigned to the mobile stroke unit received clot-busting treatment with alteplase if a mobile stroke unit was available, compared to 48% of patients who received conventional treatment in the hospital;

the time to treatment was shortened by an average of 20 minutes when a mobile stroke unit was dispatched; and

the use of a mobile stroke unit reduced the likelihood and severity of disability and death at three months by 26%.

"While we had anticipated better outcomes in the patients treated in the mobile stroke units, we are amazed by the magnitude of the effects," said lead study author Heinrich Audebert, M.D., professor in the department of neurology and Center for Stroke Research at Charité Universitätsmedizin in Berlin. "It is obvious that clot-busting treatment is most effective if it is applied in the ultra-early phase of stroke - ideally within the first or 'golden hour' of symptom onset."

Since treatment within the first hour of symptom onset happens rarely in conventional care, Audebert said health care providers should consider ways to optimize treatment so it can begin while in route to the hospital.

"Stroke treatment is more effective the earlier it starts," he said. "Just waiting until the patient arrives at the hospital is not enough anymore."

LOS ANGELES, Feb. 20, 2020 -- New research confirms that the lower 0.25mg/kg dose of the clot-busting agent tenecteplase is appropriate for eligible stroke patients and can reduce the need for mechanical clot removal, according to late breaking science presented today at the American Stroke Association's International Stroke Conference 2020. The conference, Feb. 19-21 in Los Angeles, is a world premier meeting for researchers and clinicians dedicated to the science of stroke and brain health.

The clot-busting medication alteplase was approved by the U.S. Food and Drug Administration (FDA) 25 years ago for treating clot-caused stroke (ischemic stroke) within 3 hours of symptom onset and AHA guidelines recommend alteplase up to 4.5 hours after stroke onset. Alteplase is administered as an IV drip over an hour. Alternatively, tenecteplase, a genetically modified variant of alteplase, is more convenient because it is administered as a single injection directly into the vein and restored blood flow to the brain better than alteplase in a previous trial. Two different doses of tenecteplase have been used in previous trials, and AHA guidelines include recommendations for both doses. Tenecteplase use for ischemic stroke is currently not approved by the FDA.

Researchers say that, in addition, tenecteplase may be especially beneficial for patients who need to be transferred from the hospital where they initially present to a specialized stroke center for mechanical clot removal treatment- also known as a endovascular thrombectomy, a minimally-invasive procedure in which a small tube is inserted into the arteries of the brain to remove the clot causing the stroke.

Researchers investigated whether a dose of 0.25mg/kg or 0.40mg/kg of tenecteplase prior to mechanical clot removal is optimal for stroke patients.

Three hundred ischemic stroke patients with large vessel occlusion within 4.5 hours of onset were randomized to the two doses of tenecteplase. Researchers found:

the clot was largely dissolved prior to mechanical removal in 19.3% of patients with both groups;

there were no differences in functional outcome; and

symptomatic intracranial hemorrhage occurred in numerically fewer patients treated with the smaller dose (1.3%) compared to the larger dose (4.7%), although the difference was largely due to thrombectomy-related wire perforations.

"The two doses behaved very similarly overall, and there was no advantage to increasing the dose beyond 0.25mg/kg in this study," said Bruce Campbell, M.B.B.S., B.Med.Sc., Ph.D., head of stroke at the Royal Melbourne Hospital and professorial fellow at the University of Melbourne in Parkville, Australia. "These results provide reassurance that there is a window of safety if the weight-based dose is inadvertently overestimated."

"In addition, about 34% of patients treated in rural centers had substantially improved blood flow by the time they arrived at a hospital capable of performing mechanical clot removal," Campbell said. "This treatment could be particularly important for them."

After 50 years of research and the testing of over 1,000 drugs, there is new hope for preserving brain cells for a time after stroke. Treating acute ischemic stroke patients with an experimental neuroprotective drug, combined with a surgical procedure to remove the clot improves outcomes as shown by clinical trial results published today in The Lancet.

The multi-centre, double-blinded, randomized trial, led by a team at the Cumming School of Medicine's (CSM) Hotchkiss Brain Institute and Alberta Health Services, investigates the use of the neuroprotective drug nerinetide, developed by NoNO Inc, in two scenarios in the same trial. In one scenario, nerinetide is given to patients in addition to the clot-busting drug alteplase. In the second scenario, patients who were not suitable for alteplase received only nerinetide. Both groups of patients had concurrent endovascular treatment (EVT) to remove the clot.

"Compared to placebo, almost 20 per cent more patients who received nerinetide along with endovascular treatment, but did not receive alteplase, recovered from a devastating stroke - a difference between paralysis and walking out of the hospital," says Dr. Michael Hill, MD, a neurologist at Foothills Medical Centre (FMC) and professor in the departments of Clinical Neurosciences and Radiology at the CSM. "In the patients who received both drugs, the alteplase negated the benefits of the nerinetide."

Hill says the study provides evidence of a biological pathway that protects brain cells from dying when they are deprived of blood flow. Nerinetide targets the final stage of the brain cell's life by stopping the production of nitric oxide within the cell.

"We really believe this is a new scientific observation," says Hill. "There is evidence nerinetide promotes brain cell survival, offering neuroprotection until we can extract the clot. It opens the door to a new way of treating stroke."

Images of patients' brains from the study show the expected size of the damage from the stroke is sizeably reduced when nerinetide is administered and EVT is performed among patients not concurrently receiving alteplase.

"After so many studies investigating neuroprotective drugs failed, we are extremely excited by these results," says Dr. Mayank Goyal, MD, PhD, a neuroradiologist at the FMC, and clinical professor in the Department of Radiology at the CSM. "While nerinetide is not approved for use yet, it shows the potential of a new tool to promote recovery from stroke."

Worldwide, 15 million people suffer a stroke each year - that's one every nine minutes in Canada and every 90 seconds in the United States. The results can be devastating. Ischemic stroke, the most common, is caused by a clot in a blood vessel in the brain. The sudden loss of blood flow causes brain cells to die, which can permanently affect speech, vision, balance and movement.

The international trial enrolled 1,105 patients between March 2017 and August 2019 at centres in North America, Europe, Australia, and Asia - a global academic collaboration bringing together scientists, clinicians, funding agencies, and industry.

"The collaboration between NoNO Inc., the University of Calgary and investigators at 48 leading stroke hospitals around the world has shown how effective such an academic-industry partnership can be in running high-quality, foundational stroke trials that can lead to positive changes in clinical practice," says Dr. Michael Tymianski, MD, PhD, CEO of NoNO Inc. and the inventor of nerinetide.

The results in the current study, called the ESCAPE-NA1 Trial, build on the success of the ESCAPE trial, in which the Calgary Stroke Program proved that a clot retrieval procedure known as EVT can dramatically improve patient outcomes after an acute ischemic stroke. During the procedure, a catheter is inserted in the groin and guided through blood vessels into the brain. A tiny metal mesh device is used to grab the clot and pull it out. The current study investigates whether administering nerinetide in addition to clot retrieval improves the patient's ability to recover.

MIAMI--In several new studies, University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science researcher Katharine Mach and colleagues explore the importance of learning and knowledge in environmental decision-making and the different ways in which scientific knowledge can become more relevant and useful for societies.

"Keeping people safe as the climate continues to change is a big challenge," said Mach, an associate professor of marine ecosystems and society at the UM Rosenstiel School. "Because climate change is long-term with widespread impacts, knowledge of the risks is particularly important for prudent societal investments."

In an article for the journal Climate Policy, Mach and coauthor Noah W. Feinstein, an associate professor at University of Wisconsin-Madison, describe the importance of education in adapting to climate change. Their paper, "Three roles for education in climate change adaptation," argues that educational tools--including schools, simulations, and on-the-job training--have the potential to substantially accelerate the adaptation process.

"Education goes way beyond K-12," said Feinstein. "If we want decision-makers to make the best use of critical new information, we also need to support learning before, during, and after each decision point."

In a special issue of the journal Current Opinion in Environmental Sustainability, Mach and colleagues delve deeper into the question of what knowledge is most critical--and how it becomes useful to people increasing their preparedness for climate change. They discuss insights emerging across disciplines on the relationship between knowledge and action in decision-making surrounding climate change. The researchers suggest a set of best practices to support climate change adaptation into the future.

In the article, "Actionable knowledge and the art of engagement," Mach discusses the different approaches for making knowledge actionable, many of which involve increasing interactions between researchers and stakeholders in different ways.

"Current knowledge on climate change risks and response options has an important role to play in informing society's choices and decisions in a changing climate," said Mach. "However, often this knowledge is not as useful for people as it might be."

In the same special issue, Mach co-authored a paper on how the "co-production" of knowledge has fared for climate change adaptation. The researchers point out that the co-production of knowledge, in which researchers, practitioners, stakeholders, and decision-makers interact in processes of climate change adaptation, requires that different approaches be matched to the types of decisions and decision-making contexts at hand. It's about researchers and practitioners working together in ongoing and meaningful ways.

EAST LANSING, Mich. - A Michigan State University researcher is adding new evidence to the argument that the fat around our arteries may play an important role in keeping those blood vessels healthy.

The finding could affect how researchers test for treatments related to plaque buildup in our arteries, or atherosclerosis, an issue that can often lead to a heart attack, which is currently a leading cause of death in the United States.

The fat, known as perivascular adipose tissue, or PVAT, helps arteries do what scientists call "stress relax," or let go of muscular tension while under constant strain. This is similar to the bladder, which expands to accommodate more liquid while at the same time keeping it from spilling out.

"In our study, PVAT reduced the tension that blood vessels experience when stretched," said Stephanie Watts, MSU professor of pharmacology and toxicology in the College of Osteopathic Medicine. "And that's a good thing, because the vessel then expends less energy. It's not under as much stress."

What made the finding so exciting, Watts said, whose study was recently published in the journal Scientific Reports, is that PVAT has largely been ignored by researchers who have thought its main job was to store lipids and do little more. Now her findings, built on previous results, could help redefine the way scientists view blood vessels.

Right now, scientists only divide blood vessels into three parts, the innermost layer called the tunica intima, the middle layer called the tunica media and the outermost layer called the tunica adventitia.

Watts would like scientists to recognize PVAT as the fourth layer, which others have called tunica adiposa - tunica means a membranous sheath enveloping or lining an organ and adiposa is a synonym for fat.

"For years, we ignored this layer - in the lab it was thrown out; in the clinic it wasn't imaged. But now we're discovering it may be integral to our blood vessels," Watts said. "Our finding redefines what the functional blood vessels are and is part of what can be dysfunctional in diseases that afflict us, including hypertension. We need to pay attention to this layer of a blood vessel because it does far more than we originally thought."

Other investigators have shown that PVAT plays a role in the functioning of blood vessels, finding that it secretes substances that can cause blood vessels to relax as well as substances that can cause it to contract.

But Watts and her colleagues wanted to test whether PVAT itself, rather than the substances it secretes, might play a role in how blood vessels perform. So, they decided to test whether PVAT provides a structural benefit to arteries by assisting the function of stress relaxation.

To do that, they tested the thoracic aorta in rats and found those with intact PVAT had more stress relaxation than those without.

"My mind was blown," Watts said when she saw that the pieces with surrounding fat had measurably relaxed more than those without. "I made every single person in my lab come and look and I asked, 'Tell me if I'm hallucinating...do you think this is real?'"

Watts and her colleagues also tested other arteries and were able to duplicate the same response.

"So, this tells us, it's not just a one off," Watts said. "It's not something you see only in this particular vessel or this particular species or this particular strain. But that maybe it's a general phenomenon."

We've all feared hearing a doctor say, "We need to talk."

It's even scarier if the physician is robotic, speaks in jargon or isn't clear about next steps.

Despite known protocols and recommendations on how to break bad news to patients, many physicians report insufficient training about how to conduct these challenging conversations. Northwestern University Feinberg School of Medicine has found a better way, according to a newly published study.

A new class offered to Feinberg medical students uses an approach called "simulation-based mastery learning" to train physicians to have difficult conversations with patients in a clear and compassionate way.

Students practice with faculty and trained actors until they can demonstrate mastery of the key skills, including how to communicate news without jargon, how to listen to patients' concerns, how to react to a wide variety of emotional responses and how to clearly talk through treatment options.

The study found every medical student who received the interactive training gained the skills necessary to have these hard conversations. Additionally, 100% of students reported they would recommend the course to a colleague.

This is the first study to show it is possible to embed rigorous simulation-based mastery learning of communication skills into the clinical training of medical students. The paper was published Feb. 18 in the journal Academic Medicine.

'Knowing they have a partner in this'

"We know patients and families remember these conversations forever," said first author Dr. Julia Vermylen, assistant professor of medicine and medical education at Feinberg. "It's better to practice these skills in a simulated environment where no one is harmed so that when you do it in real life, people will understand the news, their next steps and know they have a partner in this."

Doctors have long been trained to deliver bad news by role playing with fellow students or following mnemonic devices, Vermylen said. This class is different because it uses a mastery learning approach that had previously mostly been used to teach procedures such as inserting an IV into a patient's neck. In the mastery learning approach, if a student doesn't pass at first, they have to repeat the simulations until they do, which ensures a uniform level of competency, or "excellence for all," Vermylen said.

"No student can slip through the cracks," Vermylen said. "That's the point of the mastery learning approach. There's no bell curve here."

Frequent challenges in breaking bad news

"One mistake students often make is they get so focused on the medical information that they forget to recognize the emotional impact of the news on the patient," said senior author Dr. Gordon Wood, associate professor of medicine and medical education. "When someone hears bad news, there usually is a flood of emotions and, if the doctor keeps talking about medical information in that moment, patients often report that they didn't hear anything that was said.

"Students need to learn to pause to give the patient a moment to react and they need to gain the skills to help the patient process this new reality," Wood said. "When this is done well, patients feel supported and the emotional flood recedes enough that they can begin to hear about the medical plan."

How the training works

Instructors evaluate a student's communications skills before the training by watching a one-on-one videotaped simulation of the student breaking bad news to a trained actor. (In the study, the students had to inform the patient their recent headaches were caused by a brain tumor.) The students then receive feedback on their performance and, in small groups of four to six medical students and a faculty member, they get a chance to practice the skills they missed with trained actors portraying a variety of clinical scenarios and different emotional response (e.g. sadness, anger, worry, etc.). The students are able to take a "time out" during the scenarios and brainstorm different approaches to challenging situations then restart the encounter to try the new skill.

Medical students are instructed to base their conversations on a patient's response and needs. Sometimes a patient might need more information; other times, they just need a shoulder to cry on.

Students reported liking the curriculum. As one student said, "This was definitely the first role play where I felt I truly learned a lot. It was so helpful to pause as we went along so we got real-time feedback."

"The doctor needs to serve all those needs of information, guidance and emotional support," Wood said. "We teach a general framework and set of skills, then use the simulations to practice applying it in different situations."

After the training, the students undergo another one-on-one videotaped simulation of breaking bad news to an actor. If they demonstrate mastery of the skills, they are done, but if not, they practice more until they can show mastery. In this way, the length of each student's training may vary but in the end, they all gain the skills needed to share bad news in a way that is both understandable and caring.

Before hitting the track to compete in an officially sanctioned race, some elite Paralympic sprinters must do something most runners would find incredibly unsettling: remove their legs and swap them out with ones that make them shorter.

The unusual mandate results from a recent International Paralympic Committee rule change that lowered the Maximum Allowable Standing Height (MASH) for double, below-the-knee amputees racing in prosthetic legs. The rule, intended to prevent unfair advantages, stems from the long-held assumption that greater height equals greater speed.

But a small, first-of-its kind University of Colorado Boulder study published today in the journal PLOS ONE concludes that isn't the case.

"We found that height makes no difference when it comes to maximum speed," said senior author Alena Grabowski, an assistant professor in the Department of Integrative Physiology an Director of the Applied Biomechanics Lab. "These athletes are having to buy new configurations and go through a lot of hardship and expense for a rule that is not based in science."

For the study, Grabowski and her co-authors recruited five elite sprinters with double below-the-knee amputations for a series of running trials on a treadmill. The runners sampled three different brands of blades, and five different combinations of stiffness and height within each brand for a total of 15 different tests. In each test, they were asked to start at a jog and push themselves to the maximum speed possible. Some achievied speeds as fast as 10.8 meters per second - about a two minute, 30-second per mile pace.

Meanwhile, the researchers measured how the runners' biomechanics and pace changed with each blade configuration.

They found the shape of the prostheses undoubtedly made a difference in speed, with runners achieving maximum speeds about 8% faster in "J-shaped" prostheses - think the sleek carbon-fiber blades Oscar Pistorius used in his famous 2012 Olympic sprint - than in "C-shaped" prostheses. But stiffness and height made no difference in runner speed.

"Biomechanically, the idea makes sense: Longer legs equal longer steps, so you would think you should be able to run faster," said first author Paolo Taboga, an assistant professor of biomechanics at Sacramento State University who worked on the study while a postdoctoral researcher in Grabowski's Applied Biomechanics Lab. "But we found that while you do take longer steps, you cycle your legs slower so in the end the two even out."

That reality probably holds true for runners with biological legs, too. "Being taller does not make you faster," said Grabowski.

The assumption that it does is taking a heavy toll on Paralympic hopefuls.

Since the rule change took effect in January 2018, some athletes have had to spend thousands of dollars on new prostheses and months retraining themselves to run at a shorter height.

Team USA Paralympic sprinter Regas Woods, whose profile states his height as 5'10," had to lower his standing height inches after the change and expressed his discontent on Twitter: "I'm not 5 foot 4. Thanks for making me more disabled."

Olympic hopeful Blake Leeper, a double-below-the-knee amputee vying to compete against runners with biological legs at the 2020 Games, has also been affected, with the International Association of Athletics Federation (IAAF) prohibiting him from racing in the IAAF World Championships in Qatar last fall due, in part, to the fact that his blades hadn't been classified under the new standing-height formula.

Some athletes have suffered injuries while trying to adjust to their shorter blades.

The rule could also effectively exclude amputees whose residual limbs are already long from competing at the Paralympic level, noted co-author Owen Beck, now a postdoctoral fellow at Georgia Institute of Technology.

"We would like to see fair and inclusive rules and regulations, which is the beauty of the Paralympic Games," Beck said.

The authors acknowledge that their sample size of five is small. But so is the pool of double, below-the-knee amputees sprinting at the elite level.

They see the need to do a larger study.

For now, they hope the International Paralympic Committee will take a look at their research and reconsider the height restriction.

HOUSTON - (Feb. 19, 2020) - A team of Rice University engineers has introduced the first neural implant that can be both programmed and charged remotely with a magnetic field.

Their breakthrough may make possible imbedded devices like a spinal cord-stimulating unit with a battery-powered magnetic transmitter on a wearable belt.

The integrated microsystem, called MagNI (for magnetoelectric neural implant), incorporates magnetoelectric transducers. These allow the chip to harvest power from an alternating magnetic field outside the body.

The system was developed by Kaiyuan Yang, an assistant professor of electrical and computer engineering; Jacob Robinson, an associate professor of electrical and computer engineering and bioengineering; and co-lead authors Zhanghao Yu, a graduate student, and graduate student Joshua Chen, all at Rice's Brown School of Engineering.

Yang introduced the project today at the International Solid-State Circuits Conference in San Francisco.

MagNI targets applications that require programmable, electrical stimulation of neurons, for instance to help patients with epilepsy or Parkinson's disease.

"This is the first demonstration that you can use a magnetic field to power an implant and also to program the implant," Yang said. "By integrating magnetoelectric transducers with CMOS (complementary metal-oxide semiconductor) technologies, we provide a bioelectronic platform for many applications. CMOS is powerful, efficient and cheap for sensing and signal processing tasks."

He said MagNI has clear advantages over current stimulation methods, including ultrasound, electromagnetic radiation, inductive coupling and optical technologies.

"People have been demonstrating neural stimulators on this scale, and even smaller," Yang said. "The magnetoelectric effect we use has many benefits over mainstream methods for power and data transfer."

He said tissues do not absorb magnetic fields as they do other types of signals, and will not heat tissues like electromagnetic and optical radiation or inductive coupling. "Ultrasound doesn't have the heating issue but the waves are reflected at interfaces between different mediums, like hair and skin or bones and other muscle."

Because the magnetic field also transmits control signals, Yang said MagNI is also "calibration free and robust."

"It doesn't require any internal voltage or timing reference," he said.

Components of the prototype device sit on a flexible polyimide substrate with only three components: a 2-by-4-millimeter magnetoelectric film that converts the magnetic field to an electric field, a CMOS chip and a capacitor to temporarily store energy.

The team successfully tested the chip's long-term reliability by soaking it in a solution and testing in air and jellylike agar, which emulates the environment of tissues.

The researchers also validated the technology by exciting Hydra vulgaris, a tiny octopuslike creature studied by Robinson's lab. By constraining hydra with the lab's microfluidic devices, they were able to see fluorescent signals associated with contractions in the creatures triggered by contact with the chips. The team is currently performing in-vivo tests of the device on different models.

In the current generation of chips, energy and information flow only one way, but Yang said the team is working on two-way communication strategies to facilitate data collection from implants and enable more applications.

A new study from UCLA professor of anthropology Brooke Scelza invites geneticists and sociologists to think more broadly about human fidelity and paternity.

Scelza's study, published in the journal Science Advances, uses data from a long-term anthropological study in Namibia with Himba pastoralists. She found that Himba have the highest recorded rate of what researchers call "extra-pair paternity." The term refers to an instance in which a child is born to a married couple, but the husband is not the biological father.

The rate of extra-pair paternity found among Himba is 48%, far exceeding the 1% to 10% range previously thought to be typical for humans. Having children with non-marital partners was widespread among this group. A high percentage of couples (70%) had at least one child who was fathered by someone outside the marriage.

Extra-pair paternity is typically thought to occur at the expense of the husband, who is ostensibly being "tricked" into caring for a child who is not biologically his, Scelza said. However, her team shows that Himba men and women are highly accurate at detecting extra-pair paternity in their children. And Scelza contends that men not only are aware of this pattern, but they also have a system of social norms that support the practice.

"Himba have strong beliefs about the importance of social fatherhood, that a child is yours if it is born to your wife, regardless of paternity," Scelza said. "Both the stigma that typically surrounds women having multiple partners and the bias that might lead to children being mistreated are markedly lower among Himba than they are in much of the rest of the world."

It was important for researchers to collaborate closely with members of the Himba community involved in the study for ethical and logistical reasons that come up whenever paternity is at issue. For this study, Scelza and her team, in collaboration with the community, designed a novel double-blind method of analysis, so that none of the researchers was privy to both genetic data and individual-identifying information. The team received ethical approval for the study from Namibian Ministry of Home Affairs and the University of Namibia, as well as UCLA and the State University of New York's Stony Brook University.

This research, while focusing on a small group, provides a new perspective in the study of human reproduction, Scelza said.

Generally, researchers believe that extra-pair paternity is rare among humans. Geneticists have estimated the extra-pair paternity rate in populations from the Netherlands and other European-descent communities. Historically, they have found the rate in these societies to be extremely low, from 1% to 6%.

Over the last decade, more social scientists have begun to focus on diversity and inclusivity when it comes to research samples, rather than focusing solely on people from Western societies, which has been the norm.

"Anthropologists have long emphasized the need to include diverse groups in research," said Dr. Brenna Henn, a population geneticist formerly at Stony Brook and now at UC Davis, and co-author of the study. "Geneticists are still catching up. Our study shows that paternity rates can vary widely across different populations."

Scelza emphasized that there is no "correct" or "moral" standard that researchers should think about when examining human reproductive behavior. In Himba culture, for example, extramarital sexual activity is common and not stigmatized.

"What we're starting to understand and examine is how social and biological notions of paternity reflect complex suites of locally relevant norms, traditions and cultural histories," Scelza said.

While InSight's seismometer has been patiently waiting for the next big marsquake to illuminate its interior and define its crust-mantle-core structure, two scientists, Takashi Yoshizaki (Tohoku University) and Bill McDonough (Tohoku University and University of Maryland, College Park) have built a new compositional model for Mars. They used rocks from Mars and measurements from orbiting satellites to predict the depth to its core-mantle boundary, some 1,800 km beneath the surface and have been able to suggest that its core contains moderate amounts of sulfur, oxygen and hydrogen as light elements.

Yoshizaki explains, "Knowing the composition and interior structure of rocky planets tells us about formation conditions, how and when the core separated from the mantle, and the timing and amount of crust extracted from the mantle." Early astronomers used the separation distances and orbital periods of planets and their moons to determine the size, mass and density of these bodies. Today's orbiting spacecrafts provide greater details about a planet's shape and density, but the distribution of density in its interior has remained unknown. The seismic profile of a planet supplies this critical insight. When a quake rocks a planet, sound waves travel through its interior at speeds controlled by its internal composition and temperature. Strong contrasts in density, for example, rock versus steel, cause sound waves to respond differently, revealing the core-mantle boundary depth and details of the likely composition of these different layers.

By the end of the 19th century, scientists hypothesized a metallic core inside the Earth, but it was not until 1914 that seismologists demonstrated its existence at a depth of 2,900 km. Seismologists revealed the structure of the planet's interior, which helps us to locate sources and understand the nature of earthquakes. The 4 lunar seismometers brought by Apollo astronauts, defined the Moon's core-mantle-crust structure. Mars, the second-best explored planet, received in mid-2018 its first seismometer from the InSight mission.

Compositional models for a planet are developed by bringing together data from surface rocks, physical observations, and chondritic meteorites, the primitive building blocks of the planets. These meteorites are mixtures of rock and metal, like the planets, that are composed of solids accreted from the early solar nebula. Different proportions of oxides of magnesium, silicon and iron and alloys of iron and nickel make up these solids.

Yoshizaki adds that " we found that Mar's core is only about one-sixth of its mass, whereas for the Earth it is one-third of its mass." These findings are consistent with Mars having more oxygen atoms than Earth, a smaller core and a rusty red surface. They also found higher volatile element abundances, for example sulfur and potassium, in Mars than the Earth, but less of these elements than in the chondritic meteorites.

The seismometer on NASA's InSight mission will directly test this new model of Mars when it defines the depth to the Martian core-mantle boundary. Such compositional models for Mars and Earth provide clues to the origin and nature of planets and conditions for their habitability.

Historical wood panel paintings with developed craquelure patterns - networks of fine cracks in the paint- are significantly less vulnerable to environmental variations than previously assumed, according to a study in the open access journal Heritage Science. The findings offer a potential explanation as to why heavily cracked historical paintings remain stable in environments far from 'ideal' museum conditions.

Painted wood is among the most precious and frequently exhibited category of heritage objects and among the most vulnerable to relative humidity and temperature fluctuations.

A team of researchers at the Polish Academy of Sciences, Université de Strasbourg, France and Yale University, USA investigated changes in susceptibility to fracture for the most brittle component of a wood painting - the ground layer, or gesso, a mixture of animal glue and white pigment that is applied between the wooden support and the paint. The gesso is strained when wood expands due to increasing humidity or contracts due to desiccation, which can leads to cracking. Knowledge of this as well as development of technical capabilities to control environment precisely have led to stringent climate control specifications for museums, both in temperature (21 or 22°C) and humidity (45-55%).

Lukasz Bratasz, the corresponding author said: "The current environmental standards for the display of painted wood allow for only moderate variations of relative humidity. The safe range was determined based on laboratory testing of when cracks start to form in new, undamaged material. However, this does not reflect the physical reality of paintings as they age and complex craquelure patterns form. Our research more accurately reflects that physical reality, accounting for changes in the susceptibility to environmental stresses as paintings age."

To investigate the development of cracks in gesso layers subject to different environmental conditions over time, the authors designed specimens of two wooden panels, which they joined with gessoes prepared according to traditional recipes. The specimens were stored at 25°C and relative humidity of 30, 50, 75 and 90% for two weeks before being subjected to splitting test, which measure how resistant gessoes are to cracking.

Using computer tomography to scan historic samples of panel painting, the authors determined the size of existing flaws in the gesso at which new cracks initiate. Those measurements were then used in a computer model of a panel painting to simulate further crack formation. Factoring in the elasticity of the materials and moisture expansion of wood, the authors found that the stress on the gesso decreased as the number of cracks increased over time.

Lukasz Bratasz said: "Stress on the gesso occurs in the areas between cracks. The larger these areas are, the more easily cracks will form. As cracks multiply and the spaces between them become smaller, stress decreases up to a point where, finally, no new cracks will form."

The authors caution that their conclusions are valid for paintings with 'opened' cracks. If cracks are filled in during conservation treatment or varnishing, the vulnerability of a painting to the environment may increase.

Lukasz Bratasz said: "Our findings offer a potential explanation as to why historical panel paintings with developed craquelure patterns remain stable, even if the environmental conditions they are stored in are far from ideal. We hope that this knowledge may contribute to development and acceptance of more moderate-cost climate control strategies in historic buildings and museums, especially ones that may have limited potential for tighter climate control."

Bioengineers at the University of California San Diego have developed a control system that could make CAR T-cell therapy safer and more powerful when treating cancer. By programming CAR T cells to switch on when exposed to blue light, the researchers controlled the cells to destroy skin tumors in mice without harming healthy tissue.

In tests in mice, administering the engineered CAR T cells and stimulating the skin tumor sites with blue LED light reduced tumor size by eight to ninefold. The results were observed in nine out of ten mice tested. Engineered CAR T cells on their own did not inhibit tumor growth.

The work is published Feb. 19 in Science Advances.

Chimeric antigen receptor (CAR) T-cell therapy is a promising new approach to treat cancer. It involves collecting a patient's T cells and genetically engineering them to express special receptors on their surface that can recognize an antigen on targeted cancer cells. The engineered T cells are then infused back into the patient to find and attack cells that have the targeted antigen on their surface.

While this approach has worked well for some types of blood cancer and lymphoma, it so far has not worked well against solid tumors. One reason is because many targeted cancer antigens are also expressed on healthy cells.

"It is very difficult to identify an ideal antigen for solid tumors with high specificity so that CAR T cells only target these diseased tumor sites without attacking normal organs and tissues," said Peter Yingxiao Wang, a professor of bioengineering at the UC San Diego Jacobs School of Engineering and the senior author of the study. "Thus, there is a great need to engineer CAR T cells that can be controlled with high precision in space and time."

To create such cells, Wang and his team installed an on-switch that would allow them to activate the CAR T cells at a specific site in the body. The switch uses two engineered proteins located inside the CAR T cell that bind when exposed to one-second pulses of blue light. Once bound together, the proteins trigger expression of the antigen-targeting receptor.

Since light cannot penetrate deeply in the body, Wang envisions that this approach could be used to treat solid tumors near the surface of the skin. For future studies, Wang is looking to collaborate with clinicians to test the approach on patients with melanoma.

People aged 65 years and over are less likely to be readmitted to hospital if they are given help with their medication for three months after discharge, new research from the University of Bradford (UK) has found.

The study - which analysed 24 trials involving over 17,500 older patients - found that support that starts in hospital and continues after discharge is most effective in reducing harm from incorrect medication. The results are published in Age and Ageing, the journal of the British Geriatrics Society. (1) The study was funded by the National Institute for Health Research (NIHR).

Many older people take multiple medicines and these often change following a stay in hospital, when they are at their most vulnerable. Changes to medicine regimens can cause confusion or misunderstandings, potentially leading patients to over-dose, under-dose or fail to take important medication at all. This can result in serious harm, readmission to hospital and in some cases can be fatal. (2)

University of Bradford study lead, Justine Tomlinson, who also works as an elderly care pharmacist, says: "When you're in hospital, everything is done for you, so for older people, being sent home and suddenly having to look after yourself can be a real shock. We know patients need more tailored support during this critical time. Our research has enabled us to assess what that support should be and how long it needs to last."

The team found that support that bridged the transition between hospital and home was more effective than support that was only delivered either at hospital or at home. This 'transitional' support was most successful in reducing hospital admissions when it lasted for at least 90 days after discharge.

Another activity that proved effective in reducing hospital readmissions was a process called 'medicines reconciliation'. This involves a professional - often a pharmacist - comparing medicines previously prescribed by the GP and those newly prescribed by the hospital to identify any omissions or conflicts. Rather than just a paper exercise, it should include speaking to the patient or their carer, says Mrs Tomlinson.

"Patients don't always take the medicines that GPs have prescribed for them, so simply looking at prescription histories won't give you the full picture," explains Mrs Tomlinson. "Sometimes patients choose not to continue a medicine or may simply have forgotten about it over time. Medicines reconciliation forms part of official guidelines, but if patients aren't involved in the process, you can still get errors."

Working with patients to help them better manage their medication and telephone follow-up after discharge were the two other activities most effective in reducing hospital admissions.

Of the 24 trials analysed for the study, only four took place in the UK, with the others conducted in other European countries, the USA, Australia, Canada, Taiwan and Singapore. Mrs Tomlinson is now drawing on interviews with patients and healthcare professionals to develop a process based on these findings that can be trialled in the UK.

"The medicine-related harm that older patients are exposed to on discharge is serious and avoidable, yet they often feel they have to accept these problems as a fact of life as they get older," says Mrs Tomlinson. "Our research shows that it doesn't have to be that way."

The palaeontologists found the remains of the ancient amphibian at the Berezovsky quarry, a fossil locality in the Krasnoyarsk Krai near the town of Sharypovo. Fossils of ancient fish, various reptiles, mammals, herbivorous and predatory dinosaurs have been previously found there. The research materials were collected on field expeditions in the mid-2010s. In these expeditions the scientists from St Petersburg University worked alongside experts from the University of Bonn (Germany), the Tomsk State University, the Zoological Institute of the Russian Academy of Sciences, and the Sharypovo Museum of Local History and Nature.

Four vertebrate fossils enabled the scientists to declare the finding of a new genus and species. These were: three trunk vertebrae and the atlas - the first and, in the case of the salamander, the only cervical vertebra. Since the atlas is a highly specialised vertebra, providing for attachment and rotation movements of the skull, it has a rather complex structure, the scientists explain. It is therefore most suitable for describing a new species as it provides much information for analysis. The amphibian proved to have belonged to the geologically oldest stem salamanders.

It was not the first time that remains of ancient salamanders had been found at the Berezovsky quarry. One of them - a basal stem salamander Urupia monstrosa, named after the nearby Uryup River - was about 50-60 centimetres long. Another one - Kiyatriton krasnolutskii - was named after a local historian Sergei Krasnolutskii, the discoverer of the fossil locality Berezovsky quarry. By contrast, this one was quite small in size (about 10-15 centimetres) and looked more like modern Hynobiidae. The newly discovered salamander, judging by the size of the vertebrae, was of medium length (about 20 centimetres).

'Salamanders first appear in the fossil records in the Middle Jurassic, including representatives of both the present-day salamander families and the most primitive ones,' said Pavel Skutschas, associate professor of St Petersburg University, doctor of biology, expert in Mesozoic vertebrates. 'When they had just appeared, salamanders made efforts to occupy different ecological niches. Thus, the stem salamanders filled the niche of large water bodies; while those close to the present-day salamanders found their niche in small water bodies. As for the newly discovered salamander, it occupied a middle position, although morphologically, it is closer to the primitive.'

The scientists not only described the external characteristics of the specimens, but were able to look inside the fossils. In this they were assisted by the experts from the 'Centre of X-ray diffraction studies' at the Research Park of St Petersburg University, where the specimens were scanned on up-to-date microtomography scanners. Based on the obtained data, the palaeontologists created 3D reconstructions of the vertebrae and described their internal structure. As expected, it proved to be very similar to that of the large stem salamanders.

The ancient amphibian received the name Egoria malashichevi - in honour of Yegor Malashichev, associate professor of the Department of Vertebrate Zoology at St Petersburg University, who, among other things, studied the morphology of caudate amphibians. 'Yegor Malashichev was a wonderful person and a very talented scientist. He supported aspiring palaeontologists and did everything to help them to stay in scientific research,' remarked Pavel Skutschas. Additionally, Malashichev studied the phenomenon of lateralisation (body asymmetries associated with the functioning of the nervous system), as well as other asymmetries in motor performance and visual perception. Yegor Malashichev's professional career was almost exclusively connected with St Petersburg University. In 1996, he graduated from the Faculty of Biology and Soil Science. In 2000, he began to teach there, and in 2003, he defended his dissertation and was awarded a PhD in biology. Sadly, in late 2018, he passed away unexpectedly.

The next step for the palaeontologists is to compare the bones of the 'Berezovsky' salamanders with the fossils from Great Britain: the 'Kirtlington' salamanders which were found at the Kirtlington quarry in Oxfordshire. The Siberian and British faunas of the mid-Jurassic time were very similar. Besides, the palaeontologists are aware of similar amphibians that lived in the territory of present-day England. 'They may be representatives of the same genera. However, to ascertain this, a detailed comparison of the palaeontological collections is required. In the coming spring, our colleagues from England will come to St Petersburg to study our research materials. We may discover that Urupia and Egoria used to have a very wide habitat, extending across Europe and Asia,' mused Pavel Skutschas.

The study, a collection of molecular data from bird species found across 41 oceanic archipelagos, reveals how the area and isolation of islands are key to determining the diversity of species they contain.

It is known that biodiversity is unevenly distributed across the planet. But why do some islands such as the Galápagos and Hawaii harbour so many unique species of birds? In the 1960's, Robert MacArthur & Edward Wilson proposed what was to become a highly influential theory in biology: the Theory of Island Biogeography. This theory predicts the number of species expected on any given island as a function of the area (size) of the island and its isolation (distance) from the mainland.

Remarkably, to date no study has shown on a global scale how island area and isolation determine the rates at which species colonise new islands, evolve new types or go extinct. These relationships have remained elusive for decades.

However, in a new study published today in Nature, a team of ornithologists, evolutionary biologists and mathematical modellers have shown for the first time how rates of island colonisation, natural extinction, and species formation vary with island size and distance from the continent.

Dr Sonya Clegg, Associate Professor of Evolutionary Ecology at the Department of Zoology, says: 'This huge collaborative effort - led by Dr Luis Valente of Museum für Naturkunde in Berlin - has allowed us to create this remarkable global dataset of island birds worldwide. This data shows that indeed, colonisation decreases with isolation, and extinction decreases with area, confirming the key components of the Theory of Island Biogeography. Importantly we were able to extend the model framework to include speciation, showing that speciation increases with both area and isolation, and furthermore, describe the precise shape of these key global biodiversity relationships for birds.'

A further fascinating result was the finding that the vast majority of island bird species represent unique evolutionary branches with no close relatives on the islands they inhabit.

Dr Valente of Museum für Naturkunde in Berlin, says: 'Islands are frequently associated with spectacular radiations - think of Darwin's finches of Galápagos, where a single coloniser went on to diversify into 15 different species - but this is not the evolutionary scenario for most of the world's island bird diversity.'

Dr Clegg says: 'It will be exciting to see how this major advance for testing island biology theory on a global scale can be applied to other taxa. How will the precise shape of relationships change when looking at ants, or mammals or reptiles? These types of comparisons will answer long-standing questions about biogeographical patterns, and no doubt stimulate new avenues for research.'