Culture

Students perform less well in end-of-term exams if they are allowed access to an electronic device, such as a phone or tablet, for non-academic purposes in lectures, a new study in Educational Psychology finds.

Students who don't use such devices themselves but attend lectures where their use is permitted also do worse, suggesting that phone/tablet use damages the group learning environment.

Researchers from Rutgers University in the US performed an in-class experiment to test whether dividing attention between electronic devices and the lecturer during the class affected students' performance in within-lecture tests and an end-of-term exam.

118 cognitive psychology students at Rutgers University participated in the experiment during one term of their course. Laptops, phones and tablets were banned in half of the lectures and permitted in the other half. When devices were allowed, students were asked to record whether they had used them for non-academic purposes during the lecture.

The study found that having a device didn't lower students' scores in comprehension tests within lectures, but it did lower scores in the end-of-term exam by at least 5%, or half a grade. This finding shows for the first time that the main effect of divided attention in the classroom is on long-term retention, with fewer targets of a study task later remembered.

In addition, when the use of electronic devices was allowed in class, performance was also poorer for students who did not use devices as well as for those who did.

The study's lead author, Professor Arnold Glass, added: "These findings should alert the many dedicated students and instructors that dividing attention is having an insidious effect that is impairing their exam performance and final grade.

"To help manage the use of devices in the classroom, teachers should explain to students the damaging effect of distractions on retention - not only for themselves, but for the whole class."

This is the first-ever study in an actual classroom showing a causal relationship between distraction from an electronic device and subsequent exam performance.

BUFFALO, N.Y. - Stimulant medications are an effective treatment for Attention-Deficit/Hyperactivity Disorder (ADHD). In the classroom, parents and teachers say that medications like methylphenidate (MPH) can reduce symptoms and improve behavior.

Although stimulants have been in use for decades to treat ADHD in school-aged children, just how they work hasn't been clear. But the results of a new study in the Journal of Child Psychology and Psychiatry is filling in critical gaps about the role of improved cognitive functions.

"This is the first study to demonstrate that improving short-term working memory and the ability to inhibit are at least part of the way that stimulants work and improve outcomes for ADHD in the classroom," says Larry Hawk, a professor in UB's Department of Psychology and the paper's lead author.

Knowing how frontline treatments like MPH work can help develop better treatments, both pharmacological and behavioral, that target certain mechanisms and processes or contribute to developing equally effective pharmacotherapies with fewer side effects than those currently in use.

"It's estimated that it takes 15 to 20 years to go from animal research to an approved medication, at a cost of roughly $500 million to $2 billion," says Hawk. "Knowing how one treatment works gives us clues about what to target in developing new treatments. That can save a lot of time, energy and money."

Hawk says researchers often have a good hypothesis to explain the efficacy of certain medications, but for many treatments, their workings remain a mystery.

In the case of stimulant treatment of ADHD, improved classroom behavior and seatwork completion are well-documented clinical benefits. There's also laboratory evidence that stimulants improve a wide range of cognitive processes, including working memory (holding and manipulating information in your mind), the ability to inhibit (such as remembering to raise your hand rather than shout out an answer) and sustained attention (staying on task for long periods of time), key problem areas for many school-aged children with ADHD, according to Hawk.

These separate lines of evidence from clinical and laboratory science suggest that MPH works through those basic cognitive processes.

"But you really haven't demonstrated that," says Hawk. "It's just a pattern of association."

To provide a more definitive test of the idea, the researchers combined the clinical and laboratory worlds to examine basic cognition and clinical outcomes in the same children at the same time. In small groups over three summers, the study's 82 children ages 9-12 completed a one-week summer program. The children completed a range of activities, including sports and games, arts and crafts, three math classes, and computerized assessments of their cognitive abilities.

On each day, each child received either placebo or a low or moderate dose of stimulant medication. The researchers looked at how well children's response to medication on the cognitive tasks accounted for how much the medication improved their classroom behavior and number of math problems solved.

"The results provide the strongest evidence to date that stimulants like methylphenidate improve classroom behavior and performance by enhancing specific cognitive processes. Specifically, the more medication helped kids hold and manipulate information in working memory (like being able to remember things in reverse order) and the more it helped children inhibit responses 'on the fly', the greater the classroom benefit. These data are the strongest yet to suggest those are the mechanisms by which the medication is working," says Hawk.

When discussing how the findings might contribute to new treatments, Hawk points out that this work could guide the search for novel medications. He also notes that some of the best ways to improve basic cognitive processes likely do not involve medication.

"Behavioral treatment and parent training may strengthen these cognitive processes indirectly," he says. "Both can be used to enhance executive function - and behavior - by systematically and gradually reinforcing greater and greater self-control. Whether that is how these treatments work, or whether they would work even better if they directly targeted working memory and inhibition, remains to be seen."

Hawk says he'd like to extend this line of work to the real-world classroom setting or even outside of school with homework completion and peer interaction.

"This is one of two pieces of research that I feel most proud of in my career," says Hawk. "It takes a lot to walk in both the clinical and the basic science worlds. But when we put them together the way our team did here, we can really break new ground.

"I hope that we and others are now able to take those next steps and turn these novel findings into even more practical outcomes for families."

ATLANTA--A thin gap has been discovered on the Hertzsprung-Russell Diagram (HRD), the most fundamental of all maps in stellar astronomy, a finding that provides new information about the interior structures of low mass stars in the Milky Way Galaxy, according to a study led by astronomers at Georgia State University.

Just as a graph can be made of people with different heights and weights, astronomers compare stars using their luminosities and temperatures. The HRD is a "family portrait" of the stars in the Galaxy, where stars such as the Sun, Altair, Alpha Centauri, Betelgeuse, the north star Polaris and Sirius can be compared. The newly discovered gap cuts diagonally across the HRD and indicates where a crucial internal change occurs in the structures of stars. The gap outlines where stars transition from being larger and mostly convective with a thin radiative layer to being smaller and fully convective.

Radiation and convection are two ways to transfer energy from inside a star to its surface. Radiation transfers energy through space, and convection is the transfer of energy from one place to another by the movement of fluid.

The researchers estimate that stars above the gap contain more than about one-third the mass of the Sun, and those below have less mass. Because different types of stars have different masses, this feature reveals where different types of interior structures are on the HRD. The gap occurs in the middle of the region of "red dwarf" stars, which are much smaller and cooler than the Sun, but compose three of every four stars in the solar neighborhood. The findings are published in the journal The Astrophysical Journal Letters.

"We were pretty excited to see this result, and it provides us new insights to the structures and evolution of stars," said Dr. Wei-Chun Jao, first author of the study and a staff astronomer in the Department of Physics and Astronomy at Georgia State.

In 2013, the European Space Agency (ESA) launched the Gaia spacecraft to make a census of the stars in the Milky Way Galaxy and to create a three-dimensional map. In April 2018, the ESA released results of this mission, revealing an unprecedented map of more than one billion stars in the Galaxy, a 10,000-fold increase in the number of stars with accurate distances. The research team led by Georgia State plotted nearly 250,000 of the closest stars in the Gaia data on the HRD to reveal the gap. Georgia State's researchers have studied the distances to nearby stars for years, which enabled them to interpret the results and notice this thin gap.

The team is now working to pinpoint why the gap is present. Using results from a theoretical computer model that simulates the activity inside the stars, it appears the gap is caused by a slight shrinking in size if a star is convective all the way through.

A new drug discovery system allows scientists to specifically target members of an important family of enzymes, called phosphatases, which were previously considered mostly "undruggable".

Scientists from the Medical Research Council (MRC) Laboratory of Molecular Biology, in Cambridge, UK, demonstrated the capabilities of the new system by identifying a molecule that could successfully target a phosphatase to reduce the accumulation of Huntington's disease-associated proteins in the brains of mice.

The findings, published in Cell, could enable scientists to screen for drugs that can target specific phosphatases. Phosphatases are a type of enzyme that are a key part of signalling in cells - turning processes on and off. Most signalling starts with an activation signal - often when a type of enzyme called a kinase attaches a chemical tag, a phosphate group, to specific proteins to change their function. The signal is stopped by phosphatase enzymes, which cut off the phosphate group.

There are more than 200 types of phosphatases involved in many different processes in cells, so any drug must selectively target only the right one, otherwise it will produce serious side-effects or kill the cell.

Many drugs have been developed that can target specific kinases (such as anti-cancer drugs), but developing drugs that can specifically target particular phosphatases has proved difficult - because the functional part that cuts off phosphate groups is common to all phosphatases, so drugging one phosphatase inhibits hundreds of them and kills cells.

Dr Anne Bertolotti from the MRC Laboratory of Molecular Biology, who led the study, said: "For decades, with no way to selectively target phosphatases, research into them has lagged behind kinases and they've been described as undruggable. Our new system is only a first step, but we hope cracking this problem will stimulate phosphatase research and drug development.

"Targeting phosphatases - instead of kinases - is like targeting the brake, rather than the accelerator, on signals in cells. By inhibiting a phosphatase, we prolong a signalling event that has already been turned on, which may offer safer ways to specifically alter signalling in cells and help to create new drugs with fewer side-effects."

The new system builds on previous work by the same scientists in which they created functional synthetic versions of phosphatase proteins.

These synthetic phosphatases are tethered to chips so they can be screened to find a molecule that binds to one type of phosphatase, but to none of the other types. The successful molecule is then tested in cells grown in a dish to check it is safe before beginning testing in mice.

Targeting Huntington's disease

The researchers used the system to discover a molecule that showed promise in a mouse model of Huntington's disease.

Many neurodegenerative diseases, such as Alzheimer's, Parkinson's and Huntingdon's diseases, feature misfolded proteins that accumulate in cells in the brain. The researchers hoped that slowing down a cell's production of proteins could leave its 'quality control machinery' with more capacity to clear up the misfolded proteins.

In this study, they aimed to slow down the cell's protein production machinery by targeting a specific phosphatase (designated 'PPP1R15B'). They used their new drug discovery platform and found a molecule, called Raphin1, that targeted only that phosphatase.

When they tested Raphin1 in a mouse model of Huntington's disease, they found it could cross into the brain where it reduced the accumulation of the disease-associated misfolded proteins in neurons. The scientists emphasise that this is early stage research and more work is needed to test if the drug will be safe or effective in humans.

Dr Anne Bertolotti said: "Since Huntington's disease runs in families and can be diagnosed genetically, early diagnosis could provide what we hope is a window of opportunity to target the disease before symptoms appear. Our unique approach manipulates cells to slow down normal functions and give them a chance to clear up the misfolded proteins that are characteristic of Huntington's. However, it will take some years before we know if this approach works in humans and is safe."

Growing a batch of carbon nanotubes that are all the same may not be as simple as researchers had hoped, according to Rice University scientists.

Rice materials theorist Boris Yakobson and his team bucked a theory that when growing nanotubes in a furnace, a catalyst with a specific atomic arrangement and symmetry would reliably make carbon nanotubes of like chirality, the angle of its carbon-atom lattice.

Instead, they found the catalyst in question starts nanotubes with a variety of chiral angles but redirects almost all of them toward a fast-growing variant known as (12,6). The cause appears to be a Janus-like interface that is composed of armchair and zigzag segments - and ultimately changes how nanotubes grow.

Because chirality determines a nanotube's electrical properties, the ability to grow chiral-specific batches is a nanotechnology holy grail. It could lead to wires that, unlike copper or aluminum, transmit energy without loss. Nanotubes generally grow in random chiralities.

The Rice theoretical study detailed in the American Chemical Society journal Nano Letters could be a step toward catalysts that produce homogenous batches of nanotubes, Yakobson said.

Yakobson and colleagues Evgeni Penev and Ksenia Bets and graduate student Nitant Gupta tackled a conundrum presented by other experimentalists at a 2013 workshop who used an alloy of cobalt and tungsten to catalyze single-walled nanotubes. In that lab's batch, more than 90 percent of the nanotubes had a chirality of (12,6).

The numbers (12,6) are coordinates that refer to a nanotube's chiral vector. Carbon nanotubes are rolled-up sheets of two-dimensional graphene. Graphene is highly conductive, but when it is rolled into a tube, its conductivity depends on the angle -- or chirality -- of its hexagonal lattice.

Armchair nanotubes -- so called because of the armchair-like shape of their edges -- have identical chiral indices, like (9,9), and are highly desired for their perfect conductivity. They are unlike zigzag nanotubes, such as (16,0), which may be semiconductors. Turning a graphene sheet a mere 30 degrees will change the nanotube it forms from armchair to zigzag or vice versa.

Penev said the experimentalists explained their work "in a way which was puzzling from the very beginning. They said this catalyst has a specific symmetry that matches the (12,6) edge, so these nanotubes preferentially nucleate and grow. This was the emergence of the so-called symmetry matching idea of carbon nanotube selective growth.

"We read and digested that, but we still couldn't wrap our minds around it," he said.

Shortly after the 2013 conference, the Yakobson lab published its own theory of nanotube growth, which showed that the balance between two opposing forces -- the energy of the catalyst-nanotube contact and the speed at which atoms attach themselves to the growing tube at the interface -- are responsible for chirality.

Five years later, that turns out to be just as true in their new paper, though with a twist. The Rice calculations show that the alloy Co7W6 promotes the formation of the Janus-like interface that ensures the necessary kink at the edge and allows carbon atoms to attach themselves to the nanotube's foundation. But the catalyst also forces the nanotube to incorporate defects that alter its initial chirality midstream.

"We uncovered two things," Yakobson said. "One is that the carbon atom types at the base of the nanotube separate into armchair and zigzag segments. The second is the tendency for the formation of defects that drive the chirality, or helicity, change. That makes (12,6) a sort of transient attractor, at least during short experiments. If they were able to grow forever, (12,6) nanotubes would eventually switch to armchairs."

The unusual growth pattern might have been diagnosed much earlier if it weren't for an age-old typo that required some dogged detective work.

"The trouble was in a standard online database that gives the crystal structure of this cobalt-tungsten alloy," said Bets, co-lead author of the paper with Penev. "One entry was wrong. That messed up the structure so badly that we couldn't use it in our density functional theory calculations."

Once they found the error, Bets and co-author Gupta went back to the 1938 German paper that was first to correctly detail the structure of Co7W6. Even with that in hand, the team's calculations used every bit of computing power they could find to simulate the energetic connections between each atom in the catalyst and carbon feedstock.

"We figured out that if we had run the calculations in series instead of in parallel, they would have taken the equivalent of at least 2,000 years of computer time," Bets said.

"This paper is remarkable in many aspects: in the timing, the amount of detail and the surprises we found," Penev said. "We've never had a project like this. We don't yet know how this will be applicable to other materials, but we're working on it."

"There are four or five experimental papers, pretty recent ones, that also show a change of chirality during growth," Bets said. "In fact, because it's a probabilistic process, it's essentially unavoidable. But until now it's never been considered in the theoretical investigation of growth."

Sophia Antipolis, July 26, 2018: Older, overweight scuba divers are being urged to shed pounds to avoid an underwater heart attack. That's the advice from a large study out today in the European Journal of Preventive Cardiology, a publication of the European Society of Cardiology (ESC).1

"Cardiac issues are now a leading factor in diving fatalities," said study author Dr Peter Buzzacott, of the University of Western Australia, in Crawley, Australia. "Divers who learned to dive years ago and who are now old and overweight, with high blood pressure and high cholesterol, are at increased risk of dying."

It is estimated that around 3.3 million Americans and 2.8 million Europeans will scuba dive this year.2 While recreational diving fatalities are rare (181 worldwide in 2015, including 35 in Europe) the number involving cardiac issues is climbing.3 From 1989 to 2015, the proportion of diving fatalities involving 50-59 year-olds increased steadily from 15% to 35%, while fatalities in the over-60s soared from 5% to 20%. Cardiac events are now the second leading cause of death behind drowning.

People who pay to go diving must learn skills and theory and be screened for fitness. But, after that initial screening, certification to scuba dive lasts for life. "This is where we see an increase in risk," said Dr Buzzacott. "It's not commonly new divers who have health problems, because they have been recently screened. It is older divers who have not looked after their health."

Until now there has been no clear picture of how common cardiovascular risk factors are among active divers. Previous research has been limited to surveys of dive club members or insured divers. This was the first study conducted among divers in the general population.

The researchers used data from the Behavioral Risk Factor Surveillance System (BRFSS), a nationally representative telephone survey of US adults conducted by the US Centers for Disease Control and Prevention (CDC). Scuba diving was included as an activity in the 2011, 2013, and 2015 surveys. The three surveys represent nearly736 million people, of whom around 498 million (68%) had been active in the previous month and, for 113,892 people (0.02%), their principal activity was scuba diving.

This analysis compared the 113,892 scuba divers with a group of 338,933 active people matched for age, sex, and state of residence whose main activity was not scuba diving. The data shows that one-third of scuba divers are aged 50 years or older. They are often well educated, more than half earn at least US$75,000 a year, and most are married with children.

A significantly greater proportion of divers (54%) had smoked cigarettes at some point compared with non-divers (46%) but more divers had given up smoking (40% versus 26%). Divers were more frequently overweight (48% versus 43%) but had lower mean body mass index overall than the non-divers (26 versus 27 kg/m2). One-third of divers (33%) had been diagnosed with high blood pressure and 30% had high cholesterol - levels that were not statistically different from the comparison group.

"I gave up smoking because of scuba diving, and I know this is relatively common from conversations I've had on dive boats with other divers," said Dr Buzzacott. "My personal advice to all smokers is to give up smoking and take up diving. Not only is it better for you, and more fun, it's cheaper!"

Dr Buzzacott advised all divers to have routine fitness assessments with their doctor, and tackle risk factors that otherwise could lead to a fatal cardiac event while diving. He noted: "Never before in history have so many people been exposing themselves to these extraordinary environmental stresses and, for the first time ever, we now have a large number of people who have spent their entire lives regularly scuba diving."

He said: "None of us are as young as we once were and it is important that we stay in shape for diving. The father of scuba, Jacques Cousteau, was diving at 90 and the current world's oldest diver is 94. He looks like he's in great shape and that is the role model for us all if we want to keep diving into our senior years. I certainly do."

During the Late Pleistocene period (between 125,000 to 12,000 years ago) two bear species roamed Europe: omnivorous brown bears (Ursus arctos) and the extinct mostly vegetarian cave bear (Ursus spelaeus).

Until now, very little is known about the dietary evolution of the cave bear and how it became a vegetarian, as the fossils of the direct ancestor, the Deninger's bear (Ursus deningeri), are extremely scarce.

However, a paper published in the journal Historical Biology, sheds new light on this. A research team from Germany and Spain found that Deninger's bear likely had a similar diet to its descendant - the classic cave bear - as new analysis shows a distinct morphology in the cranium, mandible and teeth, which has been related to its dietary specialization of a larger consumption of vegetal matter.

To understand the evolution of the cave bear lineage, the researchers micro-CT scanned the rare fossils and digitally removed the sediments so as not to risk damaging the fossils. Using sophisticated statistical methods, called geometric morphometrics, the researchers compared the three-dimensional shape of the mandibles and skull of Deninger's bear with that of classic cave bears and modern bears.

"The analyses showed that Deninger's bear had very similarly shaped mandibles and skull to the classic cave bear", explains Anneke van Heteren, lead-author of the study and Head of the Mammalogy section at the Bavarian State Collection of Zoology. This implies that they were adapted to the same food types and were primarily vegetarian.

"There is an ongoing discussion on the extent to which the classic cave bear was a vegetarian. And, this is especially why the new information on the diet of its direct ancestor is so important, because it teaches us that a differentiation between the diet of cave bears and brown bears was already established by 500 thousand years ago and likely earlier", says Mikel Arlegi, doctoral candidate at the Universities of the Basque Country and Bordeaux and co-author of the study.

Interestingly, researchers also found there are shape differences between the Deninger's bears from the Iberian Peninsula and those from the rest of Europe, which are unlikely to be related to diet.

They have come up with three possibilities to explain these differences: 1) the Iberian bears are chronologically younger than the rest, 2) the Pyrenees, acting as natural barrier, resulted in some genetic differentiation between the Iberian bears and those from the rest of Europe, 3) there were multiple lineages, with either just one leading to the classic cave bear, or each lineage leading to a different group of cave bears.

"However, more fossils are necessary to test these three hypotheses," Asier Gómez-Olivencia, Ikerbasque Researcher at the University of the Basque Country said.

Alexandria, Va., USA - At the 96th General Session of the International Association for Dental Research (IADR), held in conjunction with the IADR Pan European Regional (PER) Congress, Shiqian Gao, University of Hong Kong, SAR China, gave an oral presentation titled "Silver Nitrate With Sodium Fluoride for Caries Arrest: 18-month Results." The IADR/PER General Session & Exhibition is in London, England at the ExCeL London Convention Center from July 25-28, 2018.

Goa and co-authors aimed to compare different solutions to reduce cavitated dental caries among preschool children. Otherwise healthy three-year-old children with active dentine caries were randomly allocated into two groups, one group received semi-annual application of 25% silver nitrate solution followed by 5% sodium fluoride varnish. The other group received semi-annual application of 38% silver diamine fluoride solution followed by a placebo varnish.

Caries experience and visual plaque index were recorded at baseline and follow-up examinations. Goa found that semi-annual application of 25% silver nitrate followed by 5% sodium fluoride varnish is not considerably less effective than 38% silver diamine fluoride in arresting dentine caries among preschool children over an 18-month period.

Findings from a Rochester Institute of Technology study provide further evidence that the outskirts of spiral galaxies host massive black holes. These overlooked regions are new places to observe gravitational waves created when the massive bodies collide, the authors report.

The study winds back time on massive black holes by analyzing their visible precursors--supernovae with collapsing cores. The slow decay of these massive stars creates bright signatures in the electromagnetic spectrum before stellar evolution ends in black holes.

Using data from the Lick Observatory Supernova Search, a survey of nearby galaxies, the team compared the supernovae rate in outer spiral galaxies with that of known hosts--dwarf/satellite galaxies--and found comparable numbers for typical spiral outskirts and typical dwarf galaxies, roughly two core-collapse supernovae per millennium.

The study, "Supernova Rate beyond the Optical Radius," will appear in an upcoming issue of Astrophysical Journal Letters.

Low levels of elements heavier than hydrogen and helium found in dwarf/satellite galaxies create favorable conditions for massive black holes to form and create binary pairs. A similar galactic environment in the outer disks of spiral galaxies also creates likely hunting grounds for massive black holes, said Sukanya Chakrabarti, lead author and assistant professor in the RIT School of Physics and Astronomy.

"If these core-collapse supernovae are the predecessors to the binary black holes detected by LIGO (Laser Interferometer Gravitational-wave Observatory), then what we've found is a reliable method of identifying the host galaxies of LIGO sources," said Chakrabarti. "Because these black holes have an electromagnetic counterpart at an earlier stage in their life, we can pinpoint their location in the sky and watch for massive black holes."

The study's findings complement Chakrabarti's 2017 study, which showed that the outer parts of spiral galaxies could contribute to LIGO detection rates. The regions form stars at a comparable rate to dwarf galaxies and are low in heavy element content, creating a conducive home for massive black holes. The current study isolates potential candidates within these favorable galactic environments.

"We see now that these are both important contributors," Chakrabarti said. "The next step is to do deeper surveys to see if we can improve the rate."

Co-author Brennan Dell, a recent graduate from RIT's computer science program, analyzed the data with Chakrabarti during his undergraduate co-op.

"This work may help us determine which galaxies to be on the lookout for electromagnetic counterparts of massive black holes," Dell said.

Sexual minorities in the US are less likely to be in work or to have health insurance than their straight peers, reveal the results of a large survey, published in the online journal BMJ Open.

They also have poorer health and quality of life.

These disparities may be even wider as the study sample was predominantly white and from relatively affluent backgrounds, suggest the researchers.

Previous research indicates that sexual minorities are more likely to be out of work and to be uninsured than their straight counterparts, but these studies have focused primarily on direct comparisons of cohabiting same sex and different sex couples, and so overlooked singles and young people.

The researchers therefore drew on just under 10,000 responses from 18-32 year olds, taking part in the annual Growing Up Today Study (GUTS) in 2013. GUTS collects information in sexual identity/orientation.

Participants were asked if they had been unemployed, uninsured, or hadn't had a routine physical exam over the past year. And they were asked to rate their mobility, self-care, capacity for routine activities, and levels of pain/discomfort and anxiety/depression.

Analysis of the responses showed that sexual minorities--both men and women--were around twice as likely as their straight peers to have been unemployed and uninsured over the past year. And they were more likely to report poorer health and quality of life.

This is an observational study, and as such, cannot establish cause. But the findings prompt the researchers to note: "These sexual-orientation disparities in employment and health insurance in a population with high social status highlight the ubiquity of sexual orientation inequities in the employment and healthcare systems."

They go on to suggest that despite the US Supreme Court's recent extension of marriage rights to same sex couples, these inequalities are likely to persist, particularly as 28 states don't have any employment law covering discrimination against sexual minorities, and three actively prevent the passage or enforcement of non-discriminatory legislation.

"Until all people, regardless of sexual orientation, are treated equally in the eyes of the law, including with non-discrimination laws protecting employment, as well as housing, public accommodations and credit/lending, sexual orientation-related health disparities will persist," they conclude.

A plant's defense systems help each other. When one system fails, another one can - at least in part - take over.

Researchers at the Norwegian University of Science and Technology 's (NTNU) Department of Biology have been collaborating with colleagues from Imperial College London and The Sainsbury Laboratory to discover more about how plants defend themselves. Their results have been published in the 26 June 2018 issue of Science Signaling.

Identifying the danger

A plant's cell walls function as an outer skeleton that protects them against various threats. This structure is vital, and therefore plants have developed mechanisms that monitor the cell walls and detect when they are being damaged.

When a cell wall sustains damage, the plant will normally try to minimize the damage and repair it. The goal is to restore the plant's normal state, or equilibrium.

The plant needs to respond differently depending on the type of danger threatening it. Initially, the plant is not able to discern whether the damage to the cell wall is being caused by drought or a disease, for example.

So how can plants identify the danger and provide the right response?

Need numerous types of defense

Associate Professor Thorsten Hamann at NTNU has been central to finding the answer to this question.

"Drought requires a plant to adjust its metabolism, whereas disease requires the plant to activate various immune responses," explains Hamann.

Different chemical processes are involved depending on the threat that the plant has to respond to. Physical damage to the cell wall demands a completely different solution from the plant than disease does.

Thale cress

The researchers exposed thale cress (Arabidopsis thaliana) to various injuries to see how the plants would react.

Thale cress is a fairly common vascular plant in the Brassicaceae family. It is usually an annual, fairly easy to grow, and the 30 000 genes of the species are fully mapped.

These qualities have led to the species being used as a "model organism" by researchers to provide insight into biological processes. Their hope is that the results will prove valid for more species than just the trial species itself. In this way the researchers can learn something about several species by examining one species.

Attacking the plants

The plant's cell walls consist of proteins and assorted sugars (carbohydrates), such as cellulose, pectin and lignin.

The researchers attacked some of the plants with enzymes that break down the cell walls. Other plants had a substance added that inhibits the formation of cellulose. The researchers then investigated the plants' chemical responses.

They disconnected 27 different genes to observe the effects. Five of the genes were important in maintaining the equilibrium of the cell walls. The experiments provided a basis for identifying multiple enzymes (kinases) and channel proteins involved in the plant's defence mechanisms. A number of genes are involved in producing these substances.

Double defense duty

The most interesting finding seems to be that two defence systems can act as a kind of backup for each other.

"We found that if we blocked the plants' immune response, the mechanisms that maintain balance in the cell walls could partially compensate for this blockage. They became a kind of reserve defence system," says Hamann.

The article in Science Signaling provides a considerably improved understanding of relationships where external influences trigger specific reactions in the plants.

"We can see how different physical influences trigger different specific chemical responses," says Hamann.

Knowing that, it's easy to see that humans can influence plants to react in certain ways.

Important for agriculture

The results also have practical utility in addition to being interesting basic research.

Knowing more about the various defence mechanisms in plants opens up new possibilities for solutions that may help plants' ability to resist different threats more effectively.

The results of the thale cress experiments could play an important role for agriculture, such as in cultivating rice and corn strains that produce better crops. Annually, more than one billion tonnes of maize are produced, and rice production is around 750 million tonnes. Many people and livestock rely on these plants as a central part of their diet.

Large populations stand to experience especially tangible value from this research.

Bottom Line: A panel of 19 microRNAs identified using next-generation sequencing could categorize indeterminate thyroid nodule samples into malignant and benign.

Journal in Which the Study was Published: Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.

Authors: First author Haggi Mazeh, MD, FACS, chief of surgery, Department of Surgery, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem and senior author Iddo Ben-Dov, MD, PhD, Department of Nephrology and the Laboratory of Medical Transciptomics, Hadassah-Hebrew University Medical Center.

Background: "Thyroid nodules are extremely common and occasionally harbor cancer," explained Mazeh. "Patients who undergo evaluation of thyroid nodules often receive ambiguous results, and there are currently limited options for further management, representing a clinically unmet need."

Patients with suspicious thyroid nodules often receive fine needle aspiration biopsy (FNAB) to facilitate the diagnosis of malignancy. However, roughly 30 percent of patients who undergo this procedure encounter indeterminate results, noted Mazeh. He added that current molecular testing methods to analyze indeterminate thyroid nodules are often expensive and do not have the desired sensitivity and specificity.

Previous work conducted by Mazeh and others identified several microRNAs with altered expression in thyroid cancer. However, the specific role that these microRNAs play in cancer development and their diagnostic utility have yet to be elucidated, explained Ben-Dov.

MicroRNAs are short non-coding RNAs that regulate cell function and play a role in cancer development.

How the Study Was Conducted: To develop the microRNA panel, Mazeh and colleagues analyzed biopsies from 102 patients undergoing thyroidectomy. Once the thyroid gland was removed, ex-vivo FNAB was performed on the thyroid nodules, resulting in 274 total biopsies. Samples were categorized as benign (71 percent) or malignant (29 percent) based on pathological diagnoses, and RNA was isolated from the biopsied tissue and analyzed via deep sequencing to reveal the types and quantitites of microRNAs present.

Results: Following sequencing, Mazeh and colleagues detected 279 microRNAs in the thyroid nodules; of these, 19 had significant differential expression between the malignant and benign samples and were chosen for the diagnostic panel.

"Many of the microRNAs identified in our panel have been noted to promote thyroid cancer proliferation, migration, and invasion, while some inhibit the proliferation of thyroid cancer cells and induce apoptosis," noted Ben-Dov.

Utilizing the microRNA diagnostic panel, Mazeh and colleagues analyzed 66 biopsies from 35 patients with indeterminate pathology and found that 22 patients had malignant thyroid nodules, while 13 patients had benign thyroid nodules. Of the patients with malignancy, 15 patients were diagnosed with papillary thyroid cancer, and seven patients were diagnosed with follicular thyroid cancer.

The sensitivity, specificity, negative predictive value, positive predictive value, and overall accuracy of the diagnostic panel as compared to the gold standard pathology were 91 percent, 100 percent, 87 percent, 100 percent, and 94 percent, respectively.

Author's Comments: "Our results provide a refined list of candidate microRNA for diagnostic use, and confirms the perception that microRNA quantification is a promising form of molecular pathology," said Mazeh. "Further studies are needed to test the clinical utility of this approach in prospective patients."

Study Limitations: Limitations of the study include the use of ex-vivo FNAB biopsies, which is not an exact equivalent of the standard clinical utilization of FNAB. Furthermore, this was a single center study and should be validated in additional locations, Ben-Dov noted.

WASHINGTON, July 26, 2018 -- Air conditioners pull off the seemingly magical feat of making the air inside a home, car or shopping mall deliciously chilly. The source of that sweet relief is chemistry. In this video, Reactions explains how refrigerants and physical chemistry combine to help you beat the summer heat: https://youtu.be/PT38gaGciP4.

Alexandria, Va., USA - At the 96th General Session of the International Association for Dental Research (IADR), held in conjunction with the IADR Pan European Regional (PER) Congress, Alexandra Clark, Queen Mary University of London, Barts and The London School of Medicine and Dentistry, England gave a poster presentation titled "Exploring the Microbial Dark Matter of the Human Mouth." The IADR/PER General Session & Exhibition is in London, England at the ExCeL London Convention Center from July 25-28, 2018.

Bacterial community profiling targeting 16S rRNA genes has revolutionized knowledge of the diversity of bacteria but recently the use of metagenomic analysis has revealed the presence of bacteria not detected by both culture and traditional 16S rRNA gene sequencing. The majority of these novel organisms fall into one monophyletic group, the Candidate Phyla Radiation (CPR). In this study, Clark and co-authors investigated the presence and the diversity of CPR bacteria in the human mouth and sought to cultivate CPR representatives.

To enrich Saccharibacteria (TM7) Clark and co-authors used a combination of sequential colony hybridisation (CH) enrichment and liquid culture with potential bacterial hosts, and a culture in a mixed in-vitro biofilm model from human saliva samples. The presence of Saccharibacteria and their relative abundance were evaluated by Q-PCR, FISH and 16S sequencing.

The results showed that CH enabled two independent co-isolations of Saccharibacteria HOT352/353 with two hosts but the Saccharibacteria cultures were lost after five and eight passages. Liquid cultures resulted in stable co-culture of Saccharibacteria but higher yields were obtained when the simplified community obtained by CH was propagated as a mixed culture in the biofilm model after preliminary amplification in liquid culture.

A combination of CH and minimal biofilm-eradication concentration is highly promising for the cultivation of Saccharibacteria species. The culture of CPR bacteria will provide insight into their unusual lifestyles and metabolism and role in oral health and disease.

Alexandria, Va., USA - At the 96th General Session of the International Association for Dental Research (IADR), held in conjunction with the IADR Pan European Regional (PER) Congress, Justin Durham, Newcastle University, England, gave a poster presentation titled "DEEP Study: Modelling Persistent Orofacial Pain Management's Costs and Benefits." The IADR/PER General Session & Exhibition is in London, England at the ExCeL London Convention Center from July 25-28, 2018.

Persistent orofacial pain (POFP) impacts the daily lives of patients and can lead to significant costs for them and/or the health service provider. In this study, Durham and co-authors examined the costs and quality-of-health experienced by individuals with POFP and used the data to estimate outcomes from pain onset over an individual's life-course.

People receiving care for POFP both in community and specialist settings were followed for 24 months. Data was collected every six months on health service utilization, pain-related disability scored by the Graded chronic pain scale (GCPS) and health-related quality of life measured by quality-adjusted life years (QALYs). Regressions were conducted to show how costs and QALYs varied according to participant characteristics. The results were used to parameterize a Markov model which was used to estimate the outcomes for a cohort of POFP patients from age 25 until death.

The results showed that a high GCPS state led to significantly increased healthcare cost as well as a significant decrease in quality-of-life. A cohort of POFP patients from age 25 were assumed to all die by the age of 100 but on average would only accrue 18 QALYs per person. Given the prevalence of POFP, this further demonstrates the burden of POFP on health and illustrates the potential gains to be made from more effective care.