Tech

An evaluation of the global energy return on investment for fossil fuels and renewable sources reveals a much more level playing field than previously believed.

An enduring argument for the ongoing use of fossil fuels is their high energy return on energy investment. This refers to the ratio of how much energy a source such as coal or oil will produce compared to how much energy it takes to extract.

Previously, the estimated ratios for energy return on investment (EROI) have favoured fossil fuels over renewable energy sources. Oil, coal and gas are typically calculated to have ratios above 25:1, this means roughly one barrel of oil used yields 25 barrels to put back into the energy economy. Renewable energy sources often have much lower estimated ratios, below 10:1.

However, these fossil fuel ratios are measured at the extraction stage, when oil, coal or gas is removed from the ground. These ratios do not take into account the energy required to transform oil, coal and gas into finished fuels such as petrol used in cars, or electricity used by households.

A new study, co-authored by scientists from the Sustainability Research Institute at the University of Leeds, has calculated the EROI for fossil fuels over a 16 year period and found that at the finished fuel stage, the ratios are much closer to those of renewable energy sources - roughly 6:1, and potentially as low as 3:1 in the case of electricity.

The study, undertaken as part of the UK Energy Research Centre programme and published today in Nature Energy, warns that the increasing energy costs of extracting fossil fuels will cause the ratios to continue to decline, pushing energy resources towards a "net energy cliff". This is when net energy available to society declines rapidly due to the increasing amounts of "parasitical" energy required in the energy production.

The researchers emphasise that these findings make a strong case for rapidly stepping up investment in renewable energy sources and that the renewables transition may actually halt - or reverse - the decline in global EROI at the finished fuel stage.

Study co-author Dr Paul Brockway, an expert in energy-economy modelling at the School of Earth and Environment at Leeds, said: "Measuring energy return on investment of fossil fuels at the extraction stage gives the misleading impression that we have plenty of time for a renewable energy transition before energy constraints are a concern.

"Those measurements are essentially predicating the potential energy output of newly-extracted sources like crude oil. But crude oil isn't used to heat our homes or power our cars. It makes more sense for calculations to consider where energy enters the economy, and that puts us much closer to the precipice.

"The ratios will only continue to decline because we are swiftly reaching the point where all the easily-accessible fossil fuel sources are becoming exhausted. By stepping up investment in renewable energy sources we can help ensure that we don't tip over the edge."

Study co-author Dr Lina Brand-Correa, an expert in the social aspects of energy use on the Living Well within Limits (LiLi) project at Leeds said: "There is too much focus on the initial economic costs of transitioning to renewable energy.

"Renewable infrastructure, such as wind farms and solar panels, do require a large initial investment, which is one of the reasons why their energy return on investment ratios have been so low until now.

"But the average energy return on investment for all fossil fuels at the finished fuel stage declined by roughly 23 per cent in the 16 year period we considered. This decline will lead to constraints on the energy available to society in the not-so-distant future, and these constraints might unfold in rapid and unexpected ways.

"Once the renewable infrastructure is built and dependency on fossil fuel decreases, the energy-return-on-investment for renewable sources should go up. This must be considered for future policy and energy infrastructure investments decisions, not only to meet climate change mitigation commitments but to ensure society continues to have access to the energy it needs."

For a patient, a diagnostic error can mean the difference between life and death. While estimates vary, likely more than 100,000 Americans die or are permanently disabled each year due to medical diagnoses that initially miss conditions or are wrong or delayed.

Now a research team, led by a Johns Hopkins Armstrong Institute for Patient Safety and Quality expert, reports it has identified three major disease categories -- vascular events, infections and cancers -- that account for nearly three-fourths of all serious harms from diagnostic errors. The team's findings, based on analysis of a large repository of malpractice insurance claims, are described in a paper published online today in the journal Diagnosis.

The researchers found that diagnostic errors were the most common, most catastrophic and most costly of medical mistakes. Diagnostic errors leading to death or serious, permanent disability were associated with misdiagnosed cancers (37.8%), vascular events (22.8%) and infections (13.5%) -- categories that the team led by David Newman-Toker, M.D., Ph.D., director of the Johns Hopkins Armstrong Institute Center for Diagnostic Excellence, calls the "big three." The authors describe 15 specific "big three" conditions that together account for nearly half of all the serious, misdiagnosis-related harms. The top conditions in each category are stroke, sepsis (a blood infection) and lung cancer, respectively. These are accompanied by heart attack, venous thromboembolism (blood clots in the legs and lungs), aortic aneurysm and dissection (a rupture of the aorta), arterial thromboembolism (a blockage of the blood supply to internal organs), meningitis and encephalitis, spinal infection, pneumonia, endocarditis (a heart infection) and breast, colorectal, prostate and skin cancers.

"We know that diagnostic errors happen across all areas of medicine. There are over 10 thousand diseases, each of which can manifest with a variety of symptoms, so it can be daunting to think about how to even begin tackling diagnostic problems," says Newman-Toker, "Our findings suggest that the most serious harms can be attributed to a surprisingly small number of conditions. It still won't be an easy or quick fix, but that gives us both a place to start and real hope that the problem is fixable."

For the study, the researchers analyzed all 11,592 diagnostic error cases between 2006 and 2015 that were drawn from a list of open and closed U.S. malpractice claims documented in the national Comparative Benchmarking System (CBS) database. Frequently used as a source for patient safety research projects, CBS is owned and maintained by CRICO, the medical malpractice insurance program associated with Harvard medical institutions and their affiliates. The database includes information from 400 hospitals, including more than 30 academic and teaching hospitals covered by both member-owned and commercial insurance programs representing more than 180,000 physicians from all 50 states plus Washington, D.C., and Puerto Rico.

The research team, which included Dana Siegal, R.N., director of patient safety at CRICO Strategies, a division of CRICO, grouped all health conditions presented in the claims according to a standard, epidemiologic classification system created by the Agency for Healthcare Research and Quality, with the help of the agency's Clinical Classifications Software. This allowed the authors to identify and rank top conditions.

For example, says Newman-Toker, "There are dozens of different diagnosis 'codes' that all represent strokes. The same is true for heart attacks and some of the other conditions as well. These differences often matter more for treatment than diagnosis. To my knowledge, grouping these codes together to identify the most common harms from diagnostic error had not been done before, but doing so gives us an 'apples to apples' comparison of the frequency of different diseases causing harms."

Among diagnostic-error cases of varying severity, the median age of the patients with errant diagnoses was 49, and more than half were female. For children and young adults (0-20 years old), harms most often were from missed infections (27.6%) rather than vascular events (7.1%) or cancers (9.1%), while the reverse was true for middle aged and older adults. About half of the high-severity harm cases the researchers studied resulted in patient death, while the other half resulted in permanent disability.

Based on claims data, the analysis also found that failures of clinical judgment were identified as causes in more than 85% of the misdiagnosed cases. The researchers say this adds to growing evidence that health care systems must do more to support bedside diagnostic decision-making by clinical providers. The authors point to interventions such as deploying computer-based diagnostic decision support tools, increasing immediate access to specialists at the point of care, supporting more effective teamwork and patient engagement in diagnosis, providing routine diagnostic performance feedback for clinicians and improving diagnostic education through simulation training.

Researchers also found that most of the diagnostic errors (71.2%) associated with the malpractice claims occurred in ambulatory settings -- either in emergency departments, where missed infections and vascular events such as strokes were more of a concern, or outpatient clinics, where misdiagnoses were more likely to be cancer-related. "These findings give us a road map for thinking about what kind of problems we need to solve in which clinical settings," Newman-Toker says.

He cautions that the focus on serious harms in the analysis leaves out many chronic or long-term conditions such as migraines or multiple sclerosis that can be misdiagnosed for years or even decades, leading to substantial patient suffering even if the diseases are eventually treated. He also says there is a bias built in the types of cases brought forth by attorneys that could have affected their findings. "It's easier to bring a cancer claim forward, for example, since there's usually more of a paper trail," he says.

To address this anticipated bias, Newman-Toker and the research team analyzed previously published studies using nonclaims data from various clinical care settings. They still found that roughly three-quarters of diagnostic error cases were associated with the "big three" disease categories -- though, unlike with the malpractice claims data, vascular events and infections dominated over cancers.

"The high percentage of serious-harm cases attributable to these 'big three' categories of conditions is likely accurate, despite the inherent biases in malpractice data," Newman-Toker says.

He says the findings suggest that harms from diagnostic errors could be substantially reduced over the next decade, but only if the medical community takes seriously the National Academy of Medicine's 2015 call to action that improving diagnosis "represents a moral, professional and public health imperative." "Our current annual federal investment to fix diagnostic errors is less than what we spend each year researching smallpox, a disease eradicated in the U.S. over half a century ago," he says. "If we devoted appropriate resources to tackling misdiagnosis of the 'big three' diseases we identified, we could potentially save half of the people who die or are permanently disabled from diagnostic errors."

The researchers plan to build on their findings as they continue the phases of their planned three-part study. The next phase will estimate how frequently the 15 most common conditions are misdiagnosed, and the final phase will use nationally representative data sets to derive a population-level estimate of the total number of people in the U.S. harmed by diagnostic error each year.

ANN ARBOR, Mich. - While ankle sprain injuries are common, a new report from Michigan Medicine suggests that the rate of opioids prescribed to those patients have become uncommonly high.

"The opioid epidemic is well documented in this country," says James R. Holmes, M.D., service chief of foot and ankle, and an associate professor of orthopaedic surgery at Michigan Medicine.

"Physician prescribing and over-prescribing is part of the problem."

Holmes is the senior author on a new brief research report, published in Annals of Internal Medicine, that examined the rates of opioids prescribed to patients who experienced an ankle sprain injury.

The research team examined data from a health insurance claims database and found that of the nearly 592,000 patients diagnosed with an ankle sprain during the selected nine-year period, 11.9 percent filled an opioid prescription within seven days of diagnosis.

"When we selected out opioid-naïve individuals, or individuals who had not had an opioid prescription during the year before the sprain, 8.4 percent of these individuals were still filling a prescription for an opioid three months after the original diagnosis," Holmes says.

Treatment guidelines

Even more alarming, Holmes says that opioids have never been included in treatment recommendations for ankle sprains.

"Several evidence-based recommendations for the treatment of ankle sprains exist and include treatments such as cryotherapy, nonsteroidal anti-inflammatory drugs, functional support and exercise," he says.

"No evidence-based treatment guidelines for ankle sprains include prescribing opioids."

The study notes that most prescriptions were provided by physicians and advanced practice providers in emergency medicine and primary care settings.

"A recent study showed that approximately 25 percent of patients with ankle sprains presenting to hospital emergency departments received an opioid prescription," Holmes says.

"It's important for all physicians to understand ankle sprain treatment guidelines and the fact that initial opioid prescription seems to be linked to new persistent opioid use: in this particular study, 8.4 percent of individuals."

Achieving a milestone in artificial intelligence (AI) by moving beyond settings involving only two players, researchers present an AI that can outperform top human professionals in six-player no-limit Texas hold'em poker, the most popular form of poker played today. This system is the only AI to have bettered professional poker players at this multi-player game. In recent years, researchers have reported great strides in artificial intelligence. Often, games serve as challenge problems, benchmarks, and milestones for this progress. Past successes in such benchmarks, including in poker, have largely been limited to two-player games, however - even as poker in particular is traditionally played with more than two players. Multi-player games present fundamental additional issues for AI beyond those in two-player games. Here, applying approaches including "action abstraction" and "information abstraction" to overcome some of these issues, and in particular to reduce the number of different actions the AI needs to consider, Noam Brown and Tuomas Sandholm developed a program - dubbed Pluribus - that learned how to play six-player no-limit Texas hold'em by playing against five copies of itself. When pitted against five elite professional poker players, or with five copies of Pluribus playing against one professional, the computer performed significantly better over 10,000 hands of poker. Pluribus confirms the conventional human wisdom, say the authors, that limping (calling the "big blind" rather than folding or raising) is suboptimal for any player except the "small blind" player who already has half the big blind in the pot by the rules, and thus has to invest only half as much as the other players to call. The findings will be published during the week the 50th Edition of the World Series of Poker Main Event begins.

Researchers from the National University of Science and Technology "MISIS" developed a database that will help create new grades of steels. This will speed up the process of creating innovative steel grades with specified strength and ductility allow at least 10 times, which will allow manufacturing car bodies of the most complex shapes. Article on the research is published in "Calphad".

In modern Materials Science, the basis for the synthesis of new materials is the so-called phase state diagrams, which show the interaction of chemical elements at different temperatures. Based on this information, it is possible to predict the physical properties and microstructure of alloys, and, most importantly, the conditions and technology for their production.

By studying and collecting thermodynamic parameters, scientists create a database for use in specialized programs that allow modeling new materials. For the developers it is a kind of "cheat sheet", according to which they develop a technology for creating new materials with the required properties.

Today, the production of flexible steels for car bodies, capable of bending into the most complex shapes, but at the same time withstands the load on impact, is very topical for the industry. It is known that the strength and ductility of steel can be increased by adding lanthanum. However, the overall mechanism of rare earth elements' influence on steel properties remained unknown until recent times.

Thermodynamic database which describes the interaction of iron and carbon with lanthanum additives makes it possible to accurately assume the phase composition, crystallization temperature and microstructure of the material. Such a database is created by researchers from NUST MISIS. This data allows optimizing the development of new steels, as it significantly reduces the time to search for new compositions and conduct the necessary experiments. With the database, the period of development of new steel grades can be reduced from 1 year to 1-2 months.

"In our work, we managed to experimentally confirm all the thermodynamic data of the La-Fe-C (lanthanum-iron-carbon) system. For instance, to clarify the chemical reactions between the elements of the system we obtained about 30 alloys with different chemical compositions", Vladimir Cheverikin, paper co-author, senior researcher at NUST MISIS Center "Materials Termochemistry", explains.

According to the results of the research, scientists managed to calculate the exact crystallization temperature of steel-based alloys and various changes in their heat treatment.

Thus, now, if it is necessary to create new steel grades, it is enough to load the resulting database into the appropriate software and get a list of conditions that will optimize the processes, including heat treatment and pressure treatment.

As a cucumber plant grows, it sprouts tightly coiled tendrils that seek out supports in order to pull the plant upward. This ensures the plant receives as much sunlight exposure as possible. Now, researchers at MIT have found a way to imitate this coiling-and-pulling mechanism to produce contracting fibers that could be used as artificial muscles for robots, prosthetic limbs, or other mechanical and biomedical applications.

While many different approaches have been used for creating artificial muscles, including hydraulic systems, servo motors, shape-memory metals, and polymers that respond to stimuli, they all have limitations, including high weight or slow response times. The new fiber-based system, by contrast, is extremely lightweight and can respond very quickly, the researchers say. The findings are being reported today in the journal Science.

The new fibers were developed by MIT postdoc Mehmet Kanik and MIT graduate student Sirma Örgüç, working with professors Polina Anikeeva, Yoel Fink, Anantha Chandrakasan, and C. Cem Ta?an, and five others, using a fiber-drawing technique to combine two dissimilar polymers into a single strand of fiber.

The key to the process is mating together two materials that have very different thermal expansion coefficients -- meaning they have different rates of expansion when they are heated. This is the same principle used in many thermostats, for example, using a bimetallic strip as a way of measuring temperature. As the joined material heats up, the side that wants to expand faster is held back by the other material. As a result, the bonded material curls up, bending toward the side that is expanding more slowly.

Using two different polymers bonded together, a very stretchable cyclic copolymer elastomer and a much stiffer thermoplastic polyethylene, Kanik, Örgüç and colleagues produced a fiber that, when stretched out to several times its original length, naturally forms itself into a tight coil, very similar to the tendrils that cucumbers produce. But what happened next actually came as a surprise when the researchers first experienced it. "There was a lot of serendipity in this," Anikeeva recalls.

As soon as Kanik picked up the coiled fiber for the first time, the warmth of his hand alone caused the fiber to curl up more tightly. Following up on that observation, he found that even a small increase in temperature could make the coil tighten up, producing a surprisingly strong pulling force. Then, as soon as the temperature went back down, the fiber returned to its original length. In later testing, the team showed that this process of contracting and expanding could be repeated 10,000 times "and it was still going strong," Anikeeva says.

One of the reasons for that longevity, she says, is that "everything is operating under very moderate conditions," including low activation temperatures. Just a 1-degree Celsius increase can be enough to start the fiber contraction.

The fibers can span a wide range of sizes, from a few micrometers (millionths of a meter) to a few millimeters (thousandths of a meter) in width, and can easily be manufactured in batches up to hundreds of meters long. Tests have shown that a single fiber is capable of lifting loads of up to 650 times its own weight. For these experiments on individual fibers, Örgüç and Kanik have developed dedicated, miniaturized testing setups.

The degree of tightening that occurs when the fiber is heated can be "programmed" by determining how much of an initial stretch to give the fiber. This allows the material to be tuned to exactly the amount of force needed and the amount of temperature change needed to trigger that force.

The fibers are made using a fiber-drawing system, which makes it possible to incorporate other components into the fiber itself. Fiber drawing is done by creating an oversized version of the material, called a preform, which is then heated to a specific temperature at which the material becomes viscous. It can then be pulled, much like pulling taffy, to create a fiber that retains its internal structure but is a small fraction of the width of the preform.

For testing purposes, the researchers coated the fibers with meshes of conductive nanowires. These meshes can be used as sensors to reveal the exact tension experienced or exerted by the fiber. In the future, these fibers could also include heating elements such as optical fibers or electrodes, providing a way of heating it internally without having to rely on any outside heat source to activate the contraction of the "muscle."

Such fibers could find uses as actuators in robotic arms, legs, or grippers, and in prosthetic limbs, where their slight weight and fast response times could provide a significant advantage.

Some prosthetic limbs today can weigh as much as 30 pounds, with much of the weight coming from actuators, which are often pneumatic or hydraulic; lighter-weight actuators could thus make life much easier for those who use prosthetics. Such fibers might also find uses in tiny biomedical devices, such as a medical robot that works by going into an artery and then being activated," Anikeeva suggests. "We have activation times on the order of tens of milliseconds to seconds," depending on the dimensions, she says.

To provide greater strength for lifting heavier loads, the fibers can be bundled together, much as muscle fibers are bundled in the body. The team successfully tested bundles of 100 fibers. Through the fiber drawing process, sensors could also be incorporated in the fibers to provide feedback on conditions they encounter, such as in a prosthetic limb. Örgüç says bundled muscle fibers with a closed-loop feedback mechanism could find applications in robotic systems where automated and precise control are required.

Kanik says that the possibilities for materials of this type are virtually limitless, because almost any combination of two materials with different thermal expansion rates could work, leaving a vast realm of possible combinations to explore. He adds that this new finding was like opening a new window, only to see "a bunch of other windows" waiting to be opened.

"The strength of this work is coming from its simplicity," he says.

On bright summer days, the sunlight all around us is breaking bad by breaking bonds. Chemical bonds.

Ultraviolet light shatters the links between atoms in the DNA of our skin cells, potentially causing cancer. UV light also breaks oxygen bonds, eventually creating ozone, and cleaves hydrogen off other molecules to leave behind free radicals that can damage tissue.

University of California, Berkeley, chemists using some of the shortest laser pulses available -- one quintillionth of a second -- have now been able to resolve the step-by-step process leading to the exploding of a chemical bond, essentially making a movie of the event. They can follow electrons indecisively bouncing around in various states in the molecule before the bond breaks, and the atoms go their separate ways.

The technique, reported last week in the journal Science, will help chemists understand and potentially manipulate chemical reactions stimulated by light, so-called photochemical reactions. Chemists and biologists, in particular, are interested in understanding how large molecules manage to absorb light energy without breaking any bonds, as happens when molecules in the eye absorb light, giving us vision, or molecules in plants absorb light for photosynthesis.

"Think about a molecule, rhodopsin, in the eye," said first author Yuki Kobayashi, a UC Berkeley doctoral student. "When light hits the retina, rhodopsin absorbs the visible light, and we can see things because rhodopsin's bond's conformation changes."

In fact, when the light energy is absorbed, a bond in rhodopsin twists, instead of breaks, triggering other reactions that result in the perception of light. The technique Kobayashi and his UC Berkeley colleagues, professors Stephen Leone and Daniel Neumark, developed could be used to study in detail how this light absorption leads to twisting after the molecule passes through an excited state called an avoided crossing or conical intersection.

To prevent the breaking of a bond in DNA, "you want to redirect the energy from dissociation to just being vibrationally hot. For rhodopsin, you want to redirect the energy from vibrating to a cis-trans isomerization, a twist," Kobayashi said. "These redirections of chemical reactions are happening ubiquitously around us, but we have not seen the actual moment of them before."

Fast laser pulses

Attosecond lasers -- an attosecond is a billionth of a billionth of a second -- have been around for about a decade and are used by scientists to probe very fast reactions. Since most chemical reactions occur rapidly, these fast-pulse lasers are key to "seeing" how the electrons that form the chemical bond behave when the bond breaks and/or reforms.

Leone, a professor of chemistry and of physics, is an experimentalist who also uses theoretical tools and is a pioneer in using attosecond lasers to probe chemical reactions. He has six of these X-ray and extreme ultraviolet (collectively, XUV) lasers in his UC Berkeley laboratory.

Working with one of the simplest of molecules, iodine monobromide (IBr) -- which is one iodine atom linked to one bromine atom -- the UC Berkeley team hit the molecules with an 8 femtosecond pulse of visible light to excite one of their outermost electrons, then probed them with attosecond laser pulses.

Pulsing the attosecond XUV laser at timed intervals of 1.5 femtosecond (a femtosecond is 1,000 attoseconds), much like using a strobe light, the researchers could detect the steps leading to the breakup of the molecules. The high-energy XUV laser was able to explore the excited energy states relative to the molecule's inner electrons, which normally do not participate in chemical reactions.

"You are kind of making a movie of the pathways of the electron when it approaches the crossing and the probability of it going along one path or along another," Leone said. "These tools we are developing allow you to look at solids, gases and liquids, but you need the shorter time scales (provided by an attosecond laser). Otherwise, you only see the beginning and the end, and you don't know what else happened in between."

The experiment showed clearly that the outer electrons of IBr, once excited, suddenly see a variety of states or places they could be and explore many of them before deciding which path to take. In this simple molecule, however, all paths lead to the electron settling on either iodine or bromine and the two atoms flying apart.

In larger molecules, which the team hopes soon to explore, excited electrons would have more choices, some where the energy goes into a twist, like with rhodopsin, or into molecular vibration without the molecules breaking apart.

"In biology, it turns out that evolution has selected things that are extremely effective at absorbing the energy and not breaking a bond," Leone said. "When something goes wrong in your chemistry is when you see diseases cropping up."

In 2014, a virus called crAssphage that infects bacteria was discovered as part of the body's intestinal environment. Now, a new study has investigated the origin and evolution of this virus, which may have coevolved with human lineage.

Published in Nature Microbiology, a recent study shows that the virus was found in the sewage of more than one-third of the world's countries. Additionally, the makeup of the virus can vary depending on in which country and city someone resides.

"The virus is both highly abundant in the human gut and represents an entirely new viral family. With this study, we were able to expand our understanding of the diversity and evolutionary history of the human microbiome globally," said Kyle Bibby, co-author of the study and associate professor and Wanzek Collegiate Chair in the Department of Civil and Environmental Engineering and Earth Sciences. "Our team at Notre Dame has been evaluating the potential uses of this newly identified virus and is developing it as an alternative to E. coli or other fecal indicator bacteria that are not specific to humans, as an indicator of fecal pollution."

The research was completed through a global collaboration of more than 115 scientists from 65 countries, allowing for the collection of a significant amount of sequencing data. This information was sampled from a variety of volunteers and from sewage samplings around the world. Genetic material data were also collected from primates as well as three pre-Columbian Andean mummies and a Tyrollean glacier mummy, which had 5,300-year-old intestinal content.

"We are in debt to all the amazing colleagues around the world who helped us explore the global diversity of this unique virus," said Robert Edwards, project lead and professor of computer science and biology from San Diego State University. "This is truly a world first in the global scope and nature of the project."

The prevalence of anal high-grade squamous intraepithelial lesions (HSIL), which precede anal cancer, is much higher in women living with HIV than previously reported, a multi-site, national study involving hundreds of patients has found. Conducted by researchers from the AIDS Malignancy Consortium, a National Cancer Institute-supported clinical trials group, the results call for new strategies to be developed for wider screening of women living with HIV, who have disproportionally higher rates of anal cancer compared to the general population of women. The study appears in Clinical Infectious Diseases.

To determine the true prevalence of anal HSIL in women living with HIV in the United States, the researchers, for the first time, conducted a full anal evaluation including a high resolution anoscopy (an examination of the anus under magnification) with directed biopsy on all 256 female study participants, not just on those who had an abnormal screening test or triage. The prevalence of anal HSIL was 27 percent, substantially higher than previous study estimates, which ranged between four to nine percent.

"We believe most prior studies of anal HSIL prevalence in women living with HIV under-represented the true percentage because only individuals with abnormal anal cytology underwent high resolution anoscopy in past studies, compared to all the participants in this new study," said Dr. Elizabeth Chiao, the co-author and principal investigator of the study. Dr. Chiao is a professor of medicine in the section of infectious diseases at Baylor College of Medicine and with the Houston VA Center for Innovations in Quality, Effectiveness and Safety.

The study was conducted at 12 academic medical centers across the United States, with the participants recruited between 2014 and 2016. The mean age of participants was 49.4 years, 64 percent were non-Hispanic black, and 67 percent were former or current smokers.

"The high prevalence of anal cancer precursors and invasive anal cancer among women living with HIV calls for greater screening in this population," said lead author Elizabeth Stier, MD, of Boston Medical Center, who is also an associate professor of obstetrics and gynecology at Boston University School of Medicine. "Because optimal screening strategies are still not yet known, prevention of anal cancer among this population should focus on identifying cost-effective strategies for the detection and management of anal cancer precursors."

DeKalb, Ill. -- A new study led by Mitch Irwin and Karen Samonds of Northern Illinois University finds that degraded rainforest habitats are having an unhealthy impact on at least one species of Madagascar's treasured lemurs, the most endangered mammal group in the world.

Irwin, Samonds and other research team members captured, measured and released 113 critically endangered diademed sifakas over the course of 19 years. They then compared the health of the animals living in intact continuous rainforest versus those in habitats disturbed and fragmented by human encroachment.

Working with a veterinarian to ensure animal safety, the scientists recorded the body mass, length and body condition of the stunning silken-furred primates, which grow to be roughly a meter in length and weigh in at about 6.5 kilograms. The results actually revealed that sifakas in some fragmented rainforest environments were doing fine--their bodies were identical to those animals in the richest environments.

But significant differences were found in the two most disturbed habitats.

"Below a critical threshold in the most degraded of all fragments, there were key differences--adults were skinnier, and the growth of immatures was delayed both in their height and weight," said Irwin, an NIU professor of anthropology and lead author of the study. The study was published June 19 in Scientific Reports, an open access journal of the Nature Research family.

Notably, the 11 lemurs living in the three lowest-quality habitats, representing three separate groups of the animals, died or disappeared during the study duration. The authors said it is unclear whether the habitats will be recolonized.

"Although anecdotal, the loss of these three groups would seem to corroborate the interpretation that their health was impacted by their low-quality habitat," Irwin said. "It's sad to actually witness a species' range shrink - it's a small step toward extinction."

For groups of sifakas in the remaining fragmented areas, both nutritional inputs and body measurements showed little distinction from groups living in optimal continuous forest, despite a noticeable degree of habitat fragmentation and disturbance.

"This suggests substantial resilience to moderate levels of habitat change," Irwin said. "If no further degradation occurs, the remaining long-term viability of groups in these fragmented areas may depend more on whether juveniles can disperse to find new groups than on nutritional inputs. If they are stuck in small isolated fragments they may die out due to inbreeding."

The study also presents the first detailed data on body proportions and dimensions of wild diademed sifakas. The animals are among the largest living lemur varieties, live in groups of two to 10 individuals and have life spans that typically exceed 20 years. Foliage is usually the major component of sifaka diets, although fruits and seeds can play a major role.

"Sifakas are long-lived animals, so they may not rapidly go extinct in these degraded habitats, but over time these threats can add up and cause these populations to be lost," Irwin said. "This research not only helps identify which groups are at risk, but identifies ways to monitor their health directly through these measurements of size and growth."

The study was conducted on sifakas living in Madagascar's Tsinjoarivo forest, part of the newly-created Tsinjoarivo-Ambalaomby protected area. Located 80 kilometers south and southeast of the capital city of Antananarivo, the rainforest is home to many spectacular varieties of lemurs, a group of primates only found in the island country.

Its preservation is being spearheaded by the NGO SADABE, a Malagasy organization created by Irwin and Samonds with Malagasy colleagues. Each year, Irwin and Samonds, a husband-and-wife team of scientists, spend a large portion of their summer conducting research in the region.

Though the Malagasy care deeply for the forest, limited economic options in poor rural areas often lead to uncontrolled and unsustainable natural resource exploitation. Over roughly the past 35 years, much of Tsinjoarivo's forests were turned to agricultural plots and trees chopped down for lumber, disturbing habitats. The rainforest's western half has been fragmented and degraded by settlers, while the eastern half is minimally disturbed.

Many studies have examined how human-caused habitat change can affect wildlife populations. But wild animals, especially highly intelligent primates, are very flexible. "They can change their diet and movement patterns to respond to changing conditions," Irwin said. "You really need direct indicators of health to know if those changes reflect an underlying threat to the population."

Samonds and Irwin continue to collect data this summer.

"For this kind of research, you need a long-term database," said Samonds, an NIU professor of biological sciences. "Basic health parameters such as body size and condition are perhaps the best tools for judging population viability, but getting the measurements typically requires captures, which are often challenging."

DALLAS, July 10, 2019 -- African American children living in socioeconomically disadvantaged neighborhoods are significantly less likely than their Caucasian counterparts in disadvantaged or wealthier areas to receive CPR from a bystander, according to new research in Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.

Prior studies have examined bystander CPR rates in adults, but this is the first time racial and socioeconomic factors have been analyzed exclusively in children in the United States.

An estimated 7,000 children suffer cardiac arrests outside the hospital each year, according to American Heart Association statistics.

Investigators at Children's Hospital of Philadelphia (CHOP) used the Cardiac Arrest Registry to Enhance Survival (CARES) database to examine factors influencing bystander CPR rates for pediatric non-traumatic out of hospital cardiac arrests from 2013-2017.

A total of 7,086 cardiac arrests were noted in the CARES catchment area between 2013 and 2017 with 61% occurring in infants, 60% in boys, 31% among white kids, 31% among black kids, 10.5% among Hispanics, 3% other and 24% where ethnicity was unknown.

Among the findings:

Overall, 3,399 children (48%) received bystander CPR.

Compared to white children, bystander CPR was 41% less likely for black kids; 22% less likely for Hispanics and 6% less likely among other ethnic groups.

Black children living in majority black neighborhoods with high unemployment, low education and low median income were almost half as likely to receive bystander CPR compared to white children with rates of (59.7% versus 32.1%).

"We believe this is the first study to describe the possible role of racial and sociodemographic factors in provision of bystander CPR to pediatric cardiac arrest in the United States," said lead investigator Maryam Naim, M.D., a pediatric cardiac intensive care physician at CHOP.

In 2017, the researchers published initial data from the study, but at that time the reported associations were unclear, noted lead investigator Maryam Naim, M.D.

"When analyzing the epidemiology of bystander CPR in children in the United States [in 2017] we found lower bystander CPR rates in black and Hispanic children compared to white children but weren't sure if this was due entirely to racial disparities or if it was also associated with neighborhood socioeconomic factors like income, employment, and educational status," said Naim, a pediatric cardiac intensive care physician at CHOP.

These results demonstrate a critical need for focused intervention in low-income, non-white, lower education neighborhoods where targeted CPR training might enhance outcomes in children, Naim said.

"As most bystander CPR is provided by family members, lower response rates are likely due to a lack of CPR training and recognition of cardiac arrests," she said, noting that teaching CPR to parents before a newborn is released from the hospital, or during pediatrician visits would be good opportunities for such training.

A new study from researchers at the Universities of Bath and Bristol suggests that doctors should rethink which drugs they prescribe to help smokers with mental health conditions kick the habit.

Their results highlight that the most effective drug at helping individuals to stop smoking is less likely to be prescribed to people with mental health conditions.

People with mental health conditions, such as anxiety or depression, are twice as likely to smoke compared to the general population. They tend to smoke more cigarettes per day, be more heavily addicted, and more likely to relapse when they try to quit. And whereas smoking rates in the UK have declined over recent decades, smoking rates have changed relatively little for people with mental health conditions.

Most smokers wishing to quit are prescribed one of two common smoking cessation drugs: nicotine replacement therapy (NRT) or varenicline. Recent randomised trials and observational studies have found that patients prescribed varenicline are more likely to stop smoking compared to those prescribed NRT.

But there have been concerns around the psychological safety of varenicline, with doctors reluctant to prescribe the drug to smokers with mental health conditions. In fact, the best evidence shows that varenicline is not associated with worse mental health outcomes.

The new study, published today [Wednesday 10 July] in the journal Nicotine & Tobacco Research, compares rates by which patients prescribed NRT* and varenicline** succeed in giving up, and what effects the drugs have on individual's mental health.

Drawing on data from over 200,000 smokers, it compares outcomes for patients with and without mental health conditions prescribed both types of drug. The results highlight that:

Compared to smokers without mental health conditions, smokers with these conditions were 31% less likely to be prescribed varenicline than NRT.

Smokers with mental health conditions who were prescribed varenicline were 19% more likely to have successfully quit at two years follow-up, than smokers who were prescribed NRT.

Varenicline is more effective than NRT in helping patients stop smoking and there was little 'evidence that varenicline was adversely associated with poorer mental health outcomes'. In general, varenicline was associated with better mental health outcomes.

Lead researcher, Dr Gemma Taylor from the University of Bath's Addiction & Mental Health Group with the Department of Psychology explains: "Smoking is still the world's leading cause of preventable illness and death. One in every two smokers will die because of their addiction unless they quit. Yet, whilst smoking rates have declined over recent decades for the general population, prevalence has not shifted to the same extent in people with mental health conditions who disproportionately suffer from smoking related mortality and morbidity and lower life expectancy.

"This study is about addressing this public health challenge to see whether assumptions about prescriptions could be challenged to give patients wishing to quit a better chance of success. Our results, in combination with results from clinical trials, suggest that doctors should rethink prescription practice in view of the benefits varenicline could bring to help those with mental health conditions stop smoking. Stopping smoking has clear physical health benefits, and there is growing evidence that stopping smoking is associated with better mental health too, benefits that could be as large as taking anti-depressants."

The research team conducted the study using electronic medical records from 654 general practices in England from 2006-15 via the Clinical Practice Research Database.

Comparing patients' success in quitting smoking using either NRT or varenicline, they focused on rates by which patients with mental health conditions gave up at three, six and nine month windows, as well at one, two and four years after first prescription.

The team also observed that across all patients, NRT and varenicline prescribing declined overtime. This could be because NHS Stop Smoking Services are being decommissioned from primary care.

Professor Ann McNeill, Professor of Tobacco Addiction, King's College London and co-Chair of the Mental Health and Smoking Partnership said: "People with mental health conditions are more likely to smoke and smoke heavily than those without, and this contributes to them dying much earlier. Doctors should therefore be pulling out all the stops to help these smokers to quit, but this research involving nearly 200,000 smokers, shows that this is not happening.

"Smokers with mental conditions are less likely to be prescribed varenicline than nicotine replacement therapy, despite the authors finding varenicline to be more effective and generally associated with better mental health outcomes."

Questions commonly used to explore the "Big Five" personality traits--Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism--generally fail to measure the intended personality traits in developing countries, according to a new study. This is because measurement of these traits relies on surveys typically applied to White Educated Industrialized Rich and Democratic (WEIRD) populations. The Big Five personality trait model is used to inform issues related to crime, employment, and wages in high-income countries. Increasingly, it has been applied to explore related issues in middle- and low-income countries, too. To better understand if this approach is valid in these countries, Richard Laajaj and his team analyzed data including 29 face-to-face surveys conducted with over 90,000 respondents, often in their local language, across 23 low and middle-income countries. Their findings included that the relationship between Conscientiousness--a trait particularly predictive of earnings in the U.S.--was not a significant income predictor in 10 of the 14 developing countries. And also in contrast with most findings in WEIRD populations, Openness appears to be a strong predictor of income in developing countries, the authors say. However, data the team collected for the same set of countries via the internet more closely reflected the Big Five traits as observed in WEIRD populations--suggesting cultural differences are not the main driver of the surveys' low validity. Rather, say the authors, language used to administer the survey may be a key influence, as surveyors can explain things differently in person. The researchers suggest several factors may explain why the survey questions were less valid in the surveyed countries, including stronger bias in these places towards providing agreeable responses during face-to-face interviews. "It really gives us a warning to be careful before we start expanding the use of these surveys too much," says Laajaj. "We need to adapt them more to this context and perhaps combine them with other ways to capture these abilities and these personality traits. That can have a lot of impact on future policies." Lajaaj and the team suggest reducing survey biases by randomly assigning surveyors, improving surveyor training, and shifting to self-administrated surveys.

A study of 86 patients reveals how drugs used for anesthesia can induce life-threatening anaphylaxis (a dangerous type of allergic reaction) through an alternative immune pathway. Their findings help to answer a conundrum in allergy research - why the classic explanation of anaphylaxis does not appear in all patients - and could guide the development of diagnostics to lower the risk of anaphylaxis during anesthesia. Drug-induced anaphylaxis most commonly occurs in response to antibiotics and neuromuscular-blocking agents (NMBAs), a type of drug commonly used to sedate patients during medical procedures. Anaphylaxis induced by NMBAs occurs in approximately 1 in 10,000 medical procedures. The condition has typically been attributed to immune responses triggered by the antibody IgE, but such responses do not appear in up to 20% of anaphylactic patients. Friederike Jönsson and colleagues hypothesized that these IgE-independent reactions could be triggered by immune pathways involving macrophages and neutrophils. They analyzed plasma samples from 86 patients who experienced anaphylaxis in response to one of three NMBAs during general anesthesia, as well as 86 controls. Surprisingly, patients with more severe anaphylactic reactions harbored higher concentrations of NMBA-specific IgG antibodies, as well as markers of neutrophil activation and a factor named PAF. Additional experiments showed anti-NMBA IgG isolated from patients could activate neutrophils, and patients with anaphylaxis also had higher quantities of NETs - sticky traps that are secreted by neutrophils. The molecular mechanism outlined here could be responsible for IgE-independent anaphylaxis and may also worsen the severity of classical, IgE-associated reactions, the authors say.

Peptides, one of the fundamental building blocks of life, can be formed from the primitive precursors of amino acids under conditions similar to those expected on the primordial Earth, finds a new UCL study.

The findings, published in Nature, could be a missing piece of the puzzle of how life first formed.

"Peptides, which are chains of amino acids, are an absolutely essential element of all life on Earth. They form the fabric of proteins, which serve as catalysts for biological processes, but they themselves require enzymes to control their formation from amino acids," explained the study's lead author, Dr Matthew Powner (UCL Chemistry).

"So we've had a classic chicken-and-egg problem - how were the first enzymes made?"

He and his team have demonstrated that the precursors to amino acids, called aminonitriles, can be easily and selectively turned into peptides in water, taking advantage of their own built-in reactivity with the help of other molecules that were present in primordial environments.

"Many researchers have sought to understand how peptides first formed to help life develop, but almost all of the research has focused on amino acids, so the reactivity of their precursors was overlooked," said Dr Powner.

The precursors, aminonitriles, require harsh conditions, typically strongly acidic or alkaline, to form amino acids. And then amino acids must be recharged with energy to make peptides. The researchers found a way to bypass both of these steps, making peptides directly from energy-rich aminonitriles.

They found that aminonitriles have the innate reactivity to achieve peptide bond formation in water with greater ease than amino acids. The team identified a sequence of simple reactions, combining hydrogen sulfide with aminonitriles and another chemical substrate ferricyanide, to yield peptides.

"Controlled synthesis, in response to environmental or internal stimuli, is an essential element of metabolic regulation, so we think that peptide synthesis could have been part of a natural cycle that took place in the very early evolution of life," said Pierre Canavelli, the first author of the study who completed it while at UCL.

The molecules that served as substrates to help the formation of the amide bonds in the experiments are outgassed during volcanism and are all likely to have been present on the early Earth.

"This is the first time that peptides have been convincingly shown to form without using amino acids in water, using relatively gentle conditions likely to be available on the primitive Earth," said co-author Dr Saidul Islam (UCL Chemistry).

The findings may also be useful to the field of synthetic chemistry, as amide bond formation is essential for many commercially important synthetic materials, bioactive compounds and pharmaceuticals. The method used in this study is chemically unconventional but follows a pathway to ligate (join together) peptides that mimics biological processes, unlike peptide-building pathways more commonly used in chemistry laboratories that run in the opposite direction and require expensive and wasteful reagents.

The research team is furthering their studies by searching for other pathways to peptides using aminonitriles, and investigating the functional properties of the peptides that their experiments have produced, to better understand how they could have helped kick start life 4 billion years ago.