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Optical sensing is one of the most important applications of light science. It plays crucial roles in astronomy, environmental science, industry and medical diagnoses.

Despite the variety of schemes used for optical sensing, they all share the same principle: The quantity to be measured must leave a "fingerprint" on the optical response of the system. The fingerprint can be its transmission, reflection or absorption. The stronger these effects are, the stronger the response of the system.

While this works well at the macroscopic level, measuring tiny, microscopic quantities that induce weak response is a challenging task. Researchers have developed techniques to overcome this difficulty and improve the sensitivity of their devices. Some of these techniques, which rely on complex quantum optics concepts and implementations, have indeed proved useful, such as in sensing gravitational waves in the LIGO project. Others, which are based on trapping light in tiny boxes called optical resonators, have succeeded in detecting micro-particles and relatively large biological components.

Nonetheless, the ability to detect small nano-particles and eventually single molecules remains a challenge. Current attempts focus on a special type of light trapping devices called microring or microtoroid resonators -- these enhance the interaction between light and the molecule to be detected. The sensitivity of these devices, however, is limited by their fundamental physics.

In their article "Sensing with Exceptional Surfaces in Order to Combine Sensitivity with Robustness" published in Physical Review Letters (DOI: https://doi.org/10.1103/PhysRevLett.122.153902), physicists and engineers from Michigan Technological University, Pennsylvania State University and the University of Central Florida propose a new type of sensor. They are based on the new notion of exceptional surfaces: surfaces that consist of exceptional points.

Exceptional Points for Exceptionally Sensitive Detection

In order to understand the meaning of exceptional points, consider an imaginary violin with only two strings. In general, such a violin can produce just two different tones -- a situation that corresponds to a conventional optical resonator. If the vibration of one string can alter the vibration of the other string in a way that the sound and the elastic oscillations create only one tone and one collective string motion, the system has an exceptional point.

A physical system that exhibits an exceptional point is very fragile. In other words, any small perturbation will dramatically alter its behavior. The feature makes the system highly sensitive to tiny signals.

"Despite this promise, the same enhanced sensitivity of exceptional point-based sensors is also their Achilles heel: These devices are very sensitive to unavoidable fabrication errors and undesired environmental variations," said Ramy El-Ganainy, associate professor of physics, adding that the sensitivity necessitated clever tuning tricks in previous experimental demonstrations.

"Our current proposal alleviates most of these problems by introducing a new system that has the same enhanced sensitivity reported in previous work, while at the same time robust against the majority of the uncontrivable experimental uncertainty," said Qi Zhong, lead author on the paper and a graduate student who is currently working towards his doctorate degree at Michigan Tech.

Though the design of microring sensors continues to be refined, researchers are hopeful that by improving the devices, seemingly tiny optical observations will have large effects.

(Boston) - A study led by physician researchers at Boston Medical Center has shown that first milk expression within eight hours of giving birth is associated with the highest probability of mothers of very low-birth-weight infants being able to provide milk throughout hospitalization in the neonatal intensive care unit. The study results, published in Obstetrics and Gynecology, help better inform perinatal providers and new mothers how to prioritize the many aspects of perinatal care after delivery of a very low-birth-weight infant.

Mother's milk has many benefits for very low-birth-rate infants, including reduction of necrotizing enterocolitis, sepsis, and chronic lung disease, and improvement in later childhood development. However, mothers of very low-birth-rate infants often have challenges making milk. They are more likely to have complications during or after delivery and comorbid health conditions that affect milk production, such as diabetes. They are also more likely to be separated from their newborn for a prolonged period of time after birth.

Because of these challenges, lactation support for mothers of very low-birth-weight infants is crucial. The World Health Organization's Baby-Friendly Hospital Initiative suggested milk expression within six hours after birth as one strategy for support. However, evidence for this time period is limited. In addition, milk expression within six hours can be difficult due to the need for intensive monitoring of newborns and/or mothers.

"Mothers who have recently delivered very low-birth-weight infants have a number of competing needs," says Margaret G. Parker, MD, MPH, a neonatologist at Boston Medical Center and the study's corresponding author. "Our data-driven approach to determining optimal time of first milk expression can help providers balance the need for safe maternal care with effective support to create long-term lactation success."

The researchers used data from 1,157 mother-baby pairs in nine Massachusetts hospitals. The infants were all very low-birth-weight infants who spent time in the neonatal intensive care unit. They found 70 percent of infants whose mothers expressed first milk within eight hours of delivery were being fed any mother's milk at discharge or transfer, compared with 52 percent of infants whose mothers expressed first milk 9-24 hours after delivery.

The authors note that given these results, randomized control trials are needed to further establish the causal relationship between timing of first milk expression and long-term lactation success among mothers of very low-birth-weight infants.

ITHACA, N.Y. - Gravitational waves, first detected in 2016, offer a new window on the universe, with the potential to tell us about everything from the time following the Big Bang to more recent events in galaxy centers.

And while the billion-dollar Laser Interferometer Gravitational-Wave Observatory (LIGO) detector watches 24/7 for gravitational waves to pass through the Earth, new research shows those waves leave behind plenty of "memories" that could help detect them even after they've passed.

"That gravitational waves can leave permanent changes to a detector after the gravitational waves have passed is one of the rather unusual predictions of general relativity," said doctoral candidate Alexander Grant, lead author of "Persistent Gravitational Wave Observables: General Framework," published April 26 in Physical Review D.

Physicists have long known that gravitational waves leave a memory on the particles along their path, and have identified five such memories. Researchers have now found three more aftereffects of the passing of a gravitational wave, "persistent gravitational wave observables" that could someday help identify waves passing through the universe.

Each new observable, Grant said, provides different ways of confirming the theory of general relativity and offers insight into the intrinsic properties of gravitational waves.

Those properties, the researchers said, could help extract information from the Cosmic Microwave Background - the radiation left over from the Big Bang.

"We didn't anticipate the richness and diversity of what could be observed," said Éanna Flanagan, the Edward L. Nichols Professor and chair of physics and professor of astronomy.

"What was surprising for me about this research is how different ideas were sometimes unexpectedly related," said Grant. "We considered a large variety of different observables, and found that often to know about one, you needed to have an understanding of the other."

The researchers identified three observables that show the effects of gravitational waves in a flat region in spacetime that experiences a burst of gravitational waves, after which it returns again to being a flat region. The first observable, "curve deviation," is how much two accelerating observers separate from one another, compared to how observers with the same accelerations would separate from one another in a flat space undisturbed by a gravitational wave.

The second observable, "holonomy," is obtained by transporting information about the linear and angular momentum of a particle along two different curves through the gravitational waves, and comparing the two different results.

The third looks at how gravitational waves affect the relative displacement of two particles when one of the particles has an intrinsic spin.

Each of these observables is defined by the researchers in a way that could be measured by a detector. The detection procedures for curve deviation and the spinning particles are "relatively straightforward to perform," wrote the researchers, requiring only "a means of measuring separation and for the observers to keep track of their respective accelerations."

Detecting the holonomy observable would be more difficult, they wrote, "requiring two observers to measure the local curvature of spacetime (potentially by carrying around small gravitational wave detectors themselves)." Given the size needed for LIGO to detect even one gravitational wave, the ability to detect holonomy observables is beyond the reach of current science, researchers say.

"But we've seen a lot of exciting things already with gravitational waves, and we will see a lot more. There are even plans to put a gravitational wave detector in space that would be sensitive to different sources than LIGO," Flanagan said.

The FRAX® tool takes into account certain factors to determine the risk of bone fracture in the general population. In a Journal of Bone and Mineral Research study, the tool was effective at determining fracture risk for women with breast cancer who were treated with aromatase inhibitors, which cause accelerated bone loss, when combined with bone mineral density measurements.

However, the results also question the practice of considering aromatase inhibitors a "secondary cause of osteoporosis" when the FRAX® tool is used without bone mineral density, because this can lead to overestimation of fracture risk. Nonetheless, it is very important to determine fracture risk in women receiving aromatase inhibitor therapy who will most likely experience bone loss during treatment.

"We hope that our data will help to inform clinical guidelines regarding fracture risk assessment in women with breast cancer, and the incorporation of FRAX® in management algorithms of those receiving aromatase inhibitors," said lead author Dr. William D. Leslie, of the University of Manitoba, in Canada.

Elite athletes are less likely to take banned substances if they consider the morality of what they are doing, and not just the health consequences of doping, according to a new study led by the University of Birmingham and funded by the World Anti-Doping Agency (WADA).

In the study, conducted in UK, Denmark, and Greece, 1,500 athletes were asked to complete a questionnaire about two hypothetical doping situations. Participants were male and female elite football players, competing just below professional levels.

In the first of the hypothetical scenarios, the athletes were asked to imagine they were trying to improve their performance after a period of disappointing results, while in the second, they were asked to imagine themselves in a situation, where they were recovering from an injury. Following each scenario, they were asked to indicate how likely they were to take the banned substance if they were in that situation.

Across the three countries, footballers indicated a relatively higher likelihood of doping for injury recovery than for performance enhancement.

The researchers looked specifically at the emotions and attitudes toward doping anticipated by the survey participants. They found that decisions were likely to be made based on how much guilt a person was expecting to feel. Some athletes found they were able to disengage, or distance themselves from the moral aspects of doping, leading to lower feelings of guilt. For example, they thought that doping is acceptable because it helps their team, and is a way to maximize their potential. Or they might feel it is acceptable because other athletes also dope. These justifications suppress the guilt athletes expected to feel, which is what prevents us from cheating. These lower feelings of guilt, in turn, were associated with greater likelihood to dope.

Dr Maria Kavussanu, in the School of Sport, Exercise and Rehabilitation Studies at the University of Birmingham, who led the study explained: "If an athlete can justify their actions to themselves, they will feel less guilt, which makes them more likely to dope. If we reinforce the message that doping is cheating, athletes are less likely to do it."

The researchers were also interested in finding out what factors might reduce these justifications, which would ultimately allow athletes to suppress their feelings of guilt and use banned substances. The key factor which seems to protect athletes from doping was moral identity. This means how important it was to the players to be a moral person, and how strong their moral values, such as being fair or honest, were. Those players who had a strong moral identity did not use justifications for doping, expected to feel more guilt for doping, and ultimately were less likely to dope.

The researchers also found that coaches' behavior, and the 'performance climate' in which athletes were training also had a significant effect on their doping likelihood. If coaches were creating a climate in which players who made a mistake were penalised, or if they gave undue attention to the best players, athletes were more likely to turn towards banned substances. The coach can therefore play an important role in doping prevention.

The research findings are forming the basis for anti-doping interventions aimed at challenging players' attitudes towards banned substances. Funded by the World Anti-Doping Agency and the International Olympic Committee, the team has developed a series of interventions which highlight the moral angle through stories of athletes who have been affected by these issues, and what it has meant for them, and for their team mates and families.

"A lot of anti-doping messages warn athletes about taking supplements and stress the consequences of being found out - you might be fined, or banned from the sport," adds Dr Kavussanu. "But our research shows there could be a powerful moral message that is being overlooked in current anti-doping interventions worldwide. This type of messaging teaches athletes that doping is cheating, and that it has consequences for fellow athletes and team members, as well as for your own health."

Tony Cunningham, Senior Manager, Education at the World Anti-Doping Agency, says: "This study is another important step in further understanding the behaviour of doping and it gives valuable insights into how interventions can be tailored to more effectively prevent it from happening. Engaging athletes at a moral level is important, but how to do this and the types of messages an athlete should receive can be difficult to know. The research team have helped to better understand how these messages can be framed.

"The study also highlights another important aspect in the prevention of doping, that of the athlete's environment. The type of climate that is promoted by coaches and those closest to the athlete can have a significant impact on how likely someone is to dope, and this may be done unwittingly, making it all the more important for education interventions to address going forward."

Published in Psychology of Sport and Exercise, the study was led by Dr Maria Kavussanu from the University of Birmingham, with co-investigators from California State University, the University of Leipzig and the University of Thessaly.

Researchers at King's College London, in collaboration with Northumbria University, have developed a new way of detecting homemade explosives which will help forensic scientists trace where it came from.

The approach uses ion chromatography - high resolution mass spectrometry, published today in Analytica Chimica Acta. Scientists show that through using this technique, they can detect a very large number of components of homemade explosives down to very low trace amounts.

Homemade explosives are frequently used in a number of different crimes, including the Boston Marathon bombing in 2013 and the Oslo attacks in 2011. They are also used in ATM robberies. They have traditionally been very challenging to detect and trace in samples submitted for forensic analysis.

Lead author Dr Matteo Gallidabino said: "The method we developed is less time consuming and represents a viable solution for challenging explosives like these. By combining this approach with advanced data analytics, added intelligence can be retrieved from any evidence recovered. This has the potential to significantly impact criminal investigations and further enhance the role of forensics in the administration of justice."

The team successfully went on to use the new approach to interpret the time since explosives materials were handled by the original maker, analysing sweat. They were also able to analyse gunshot residue to trace the type of ammunition used.

Dr Leon Barron from King's College London said: "The technique is able to tell us so much more than just the explosives content. It detects thousands of different compounds simultaneously, which means there is an element of in-built future-proofing capability to detect new types of explosives if needed or provide critical information about where a device came from or who it belongs to."

A new analysis co-led by The Johns Hopkins University identified 25 United States counties that are most likely to experience measles outbreaks in 2019. The analysis combined international air travel volume, non-medical exemptions from childhood vaccinations, population data and reported measles outbreak information.

The analysis will be published on May 9 in The Lancet Infectious Diseases.

"There has been a resurgence of measles cases, among other vaccine preventable diseases, in the U.S. and other countries in recent years. Measles, in particular, poses a serious public health threat due to the highly contagious nature of the disease. It is therefore critical that we proactively identify areas most likely to experience outbreaks to strategically target for surveillance and control," says Lauren Gardner, an associate professor of civil engineering at The Johns Hopkins University and one of the study's corresponding authors.

As of late April, the U.S. has seen more than 700 cases of measles this year, the highest number in decades. Although measles was officially eliminated from the U.S. in 2000, the ongoing outbreak shows that the nation remains at risk.

The recent spike in cases, the researchers say, is due to reintroduction by international travelers from countries experiencing measles outbreaks, compounded by low-vaccination rates in certain localities that are fueled in part by an increasingly visible anti-vaccination movement.

"Anti-vaxxers are denying the best and very successful medical science we have and choosing instead to rely on fraudulent claims, such as a purported link to autism, that have been uniformly debunked by evidence and analysis over the last two decades," says Sahotra Sarkar, professor of philosophy and integrative biology at The University of Texas at Austin and the study's other corresponding author.

To identify the top 25 U.S. counties most likely to experience outbreaks in 2019, the research team performed a risk analysis that took the following data into account: non-medical exemption rates in each county, anonymous full-route passenger travel data from all international airports into each of the U.S. counties, county population and size and location of measles outbreaks globally.

The analysis correctly predicts the regions in Washington, Oregon and New York that have already seen major measles outbreaks this year. Furthermore, the vast majority of counties that have reported measles cases as of April 2019 are included in team's top 25 at-risk counties or lie adjacent to one of the top 25 counties. Additionally, the analysis specified the following countries that contribute most to measles risk in the U.S.: India, China, Mexico, Japan, Ukraine, Philippines and Thailand.

"Our prediction is aligned with multiple counties that have experienced measles outbreaks this year. Critically, we recommend that public health officials and policymakers prioritize monitoring the counties we identify to be at high risk that have not yet reported cases, especially those that lie adjacent to counties with ongoing outbreaks and those that house large international airports," says Gardner.

Sarkar adds that policymakers must focus on centers of vaccination resistance, as well as regions with a lot of passenger inflow from affected countries worldwide if there are even small local pockets of unvaccinated people.

"The New York borough of Brooklyn is a perfect example with a large number of unvaccinated members of an orthodox Jewish community even though the overall county vaccination rate is not low."

Chestnut Hill, MA (5/9/2019) - Opposites may attract and drive each other a little crazy, but, together, they can make satisfactory decisions despite their divergent attitudes, according to a Boston College researcher who led a study that explored how selfish and altruistic consumers join in decision making.

Consumers routinely make joint decisions with others - which restaurant to eat in, what movie to watch, or where to go on vacation. Researchers from Boston College, Georgia Tech, and Washington State University wanted to see if people with opposite attitudes could come to satisfactory decisions together.

The studies found that when paired with a selfish partner, it is better to behave altruistically rather than selfishly. Similarly, when paired with an altruistic partner, it is better to behave selfishly to achieve a desired outcome, according to the findings, reported recently in the Journal of Consumer Psychology.

In both scenarios, the paired respondents were able to come to decisions that best reflected their individual preferences, or what both partners personally liked - if they took the opposite attitude as that of their partner, said Boston College Carroll School of Management Coughlin Sesquicentennial Assistant Professor of Marketing Hristina Nikolova.

"When you see that your partner is acting selfishly, it is better to let it go and act altruistically instead; let them make the decision because this will ultimately ensure a better outcome for you than if you act selfishly too," said Nikolova, a co-author of the article "Ceding and Succeeding: How the Altruistic Can Benefit from the Selfish in Joint Decisions."

"In the joint decision-making of an altruistic and selfish consumer, the selfish partner would willingly express her desired preference, while the altruistic partner will likely accept these suggestions," Nikolova continued. "Since consumers' preferences are more similar than they recognize, an altruistic individual will likely get an option that she somewhat prefers even when a selfish partner drives the decision. Thus, regardless of who drives the decision, both partners are likely to reach a joint decision that is relatively preferred by both of them."

Conventional wisdom suggests that standing one's ground is associated with positive outcomes, Nikolova said. But that's not necessarily the case.

"In the context of joint choices, however, we find that two selfish heads do worse than one altruistic and one selfish head; two selfish consumers jointly choose options that neither of them prefers. This happens because both partners are likely to be rigidly self-oriented when negotiating with others," she said.

For those who are selfish in nature, conceding runs counter to their nature. The study found that selfish individuals are likely to meet suggestions with counteroffers even when the suggestions somewhat coincide with their own preferences, Nikolova said. And that might actually be a bad thing.

"This propensity to counteroffer rather than concede inadvertently leads to negotiation," she said. "The two selfish partners trade rejected offers until they land on an option that is further down both of their preference lists but is deemed acceptable by both partners."

There is limited research on joint decision-making in the fields of marketing and consumer behavior. Nikolova sees future studies further investigating how interpersonal orientations influence decision making. While the study examined decision outcomes among pairs of individuals, it didn't focus on how the pairs went about making their specific decisions.

She said she hopes to look at whether pairs with similar outlooks - two selfish persons, or two altruistic persons - use the same decision tactics as paired opposites. That would require a closer look at the decision process, rather than the outcome.

In a school-based survey study of all students in grades 6, 8, and 10 in Iceland, the use of pain medications was significantly higher among bullied students even when controlling for the amount of pain they felt, as well as age, gender, and socioeconomic status. The findings are published in Acta Paediatrica.

A total of 10,390 students completed anonymous surveys and answered questions about bullying, pain, and pain medication use. Bullied students tended to experience more pain than their non-bullied students, and bullied students were twice as likely to use pain medication even when controlling for experienced pain.

"Interventions aimed at reducing bullying and promoting health in schools are important and might reduce the use of analgesics in adolescents," said corresponding author Dr. Pernilla Garmy, of Kristianstad University, in Sweden.

Oncologists may soon have an accurate and inexpensive way of differentiating between types of ovarian cancer that will improve how patients are treated, thanks to findings from a national research study co-led out of the University of Alberta.

"One of the issues with ovarian cancer is that we cannot fully decipher between subtypes," said Lynne Postovit, U of A oncology researcher and co-director of the Cancer Research Institute of Northern Alberta. "This is an important problem because the different subtypes should be treated differently."

She explained that women with endometrioid-type ovarian carcinoma usually have a better prognosis for beating the disease and need a less aggressive treatment than women suffering from high-grade serous carcinomas, which is the most common and deadly form of ovarian cancer.

Unfortunately, the diagnosis of which form of ovarian cancer a woman has is wrong 10 per cent of the time.

"That doesn't sound like a big deal, but the difference in the ways that women with endometrioid versus high-grade serous are treated is significant," said Postovit, who received funding from the Lois Hole Hospital for Women through the Women and Children's Health Research Institute.

"Not knowing with complete certainty which form of cancer the patient has means that oncologists have to go with the harshest treatment regardless."

Growing weary of the cautionary and often overly aggressive one-size-fits-all treatment, Postovit, together with colleagues at the University of Calgary and Western University, looked at the proteins present in the different types of cancers.

The team found eight protein biomarkers that enable pathologists to differentiate between a endometrioid or high-grade serous carcinoma with 99.2 per cent accuracy.

"The relevance is if you know what you're looking at, you take a precision medicine approach to better tailor the treatment to the patient, so they have potentially less side-effects," she said. "This is what personalized medicine is all about--starting to look at each patient's cancer differently."

And because the study was tailored to be more practical, Postovit said the team can immediately start to test how broadly this might work.

"In fact, because it is a rather inexpensive test and involves technology we already have, there is no need to build a new paradigm. It can be taken up without costing all that much."

Postovit said the next steps are to validate the results on a larger patient cohort and then to suggest implementation, which could be within a few years.

"This is all because of philanthropic and chair funding that allows us to ask questions that normally we wouldn't," she said.

For over 100 years, scientists have sought to understand what links a person's general intelligence, health and aging. In a new study, a University of Missouri scientist suggests a model where mitochondria, or small energy producing parts of cells, could form the basis of this link. This insight could provide valuable information to researchers studying various genetic and environmental influences and alternative therapies for age-related diseases, such as Alzheimer's disease.

"There are a lot of hypotheses on what this link is, but no model to link them all together," said David Geary, Curators Distinguished Professor of Psychological Sciences in the MU College of Arts and Science. "Mitochondria produce cellular energy in the human body, and energy availability is the lowest common denominator needed for the functioning of all biological systems. My model shows mitochondrial function might help explain the link between general intelligence, health and aging."

Geary's insight came as he was working on a way to better understand gender-specific vulnerabilities related to language and spatial abilities with certain prenatal and other stressors, which may also involve mitochondrial functioning. Mitochondria produce ATP, or cellular energy. They also respond to their environment, so Geary said habits such as regular exercise and a diet with fruits and vegetables, can promote healthy mitochondria.

"These systems are being used over and over again, and eventually their heavy use results in gradual decline," Geary said. "Knowing this, we can help explain the parallel changes in cognition and health associated with aging. Also with good mitochondrial function, the aging processes will occur much more slowly. Mitochondria have been relatively overlooked in the past, but are now considered to relate to psychiatric health and neurological diseases."

Geary said chronic stress can also damage mitochondria that can affect the whole body -- such as the brain and the heart -- simultaneously.

The price tag for cutting global emissions may seem expensive, until the human toll of deaths from air pollution and climate change are factored in, new research says.

The new study in Nature Communications reports that immediate, dramatic cuts in carbon emissions - aggressive enough to meet the Paris Climate Agreement - are economically sound if human health benefits are factored in.

"Reducing greenhouse gas emissions will also reduce deaths from air pollution in communities near the emissions reductions," says Mark Budolfson, co-lead author from the University of Vermont. "These health 'co-benefits' of climate change policy are widely believed to be important, but until now have not been fully incorporated in global economic analyses of how much the world should invest in climate action."

By adding air pollution to global climate models, Budolfson and colleagues find that economically, the optimal climate policy would be more aggressive than previously thought, and would produce immediate net benefits globally.

The health benefits alone could reach trillions of dollars in value annually, depending on air quality policies that nations adopt, to help offset climate investments.

The study helps to justify immediate investments in global emission reductions by showing they will benefit the current generation of citizens while also helping to address climate change for future generations.

"We show the climate conversation doesn't need to be about the current generation investing in the further future," says Budolfson, a Fellow of the Gund Institute for Environment from UVM's College of Arts of Sciences. "By making smart investments in climate action, we can save lives now through improved air quality and health."

The team's work builds on the RICE climate model, which was developed by Yale Economist William Nordhaus, who recently recieved the Nobel Prize in Economics.

Researchers considered the costs and benefits of air pollutant emissions, which produce aerosols. Aerosols have never been fully incorporated into this type of modeling, and are important for two reasons. Aerosol pollution worsens human health, but aerosols also act to cool the earth, counterbalancing some of the warming generated by greenhouse gases.

By factoring in these additional co-benefits and co-harms, the researchers identified a climate policy that would bring immediate net benefits globally, both in health and economic terms. The strongest potential near-term health benefits are in China and India, which face among the highest death rates from air pollution.

"Some developing regions have been understandably reluctant to invest their limited resources in reducing emissions," said Noah Scovronick, a co-lead author from Emory University. "This and other studies demonstrate that many of these same regions are likely to gain most of the health co-benefits, which may add incentive for them to adopt stronger climate policies."

The researchers find that the dramatic efforts needed to meet the Paris Agreement targets of limiting global temperature rise to 2 degrees C (or 3.6 degrees F) is economically defensible. This is because the health benefits resulting from air pollution reductions can offset the near-term costs. Prior economic studies on this issue did not support such a strict climate target.

"The climate problem has several features that make it particularly difficult to solve," said Marc Fleurbaey of Princeton University. "Here, we show that accounting for the human health dimension alleviates many of these difficulties: Health benefits begin immediately, occur near where emissions are reduced, and accrue mainly in developing regions with less historical responsibility for climate change. The finding that climate policy may not in fact entail an intergenerational trade-off could completely change the framing of the debate."

MADISON -- Induced pluripotent stem (iPS) cells are among the most important tools in modern biomedical research, leading to new and promising possibilities in precision medicine. To create them requires transforming a cell of one type, such as skin, into something of a blank slate, so it has the potential to become virtually any other kind of cell in the body, useful for regenerative therapies for everything from heart disease to diabetes.

However, current methods to induce pluripotency are inefficient: In a batch of 100 cells slated for reprogramming, only five or so complete the transition. A new study published today [May 7, 2019] in Cell Reports by a team of researchers at the University of Wisconsin-Madison's Wisconsin Institute for Discovery (WID) and School of Medicine and Public Health could improve that efficiency.

It describes combined laboratory and computational methods that lead to better completion of pluripotency, a faster process, and improved understanding of how cells become reprogrammed from one cell type to another, for instance, transforming a skin cell to a cardiac cell. And it includes some surprises, the authors say.

"The cells undergoing reprogramming do not have to do so in a stepwise manner," says graduate student Zafirah Zaidan, one of the study's lead authors.

Traditionally, scientists thought certain steps must occur sequentially during reprogramming. This was based on measures of gene expression across entire populations of cells at various time points, leading to average expression profiles for the whole group. They thought that for a cell to be successfully reprogrammed, the -genes that code for the specific functions of the differentiated cell (skin) must be suppressed, or "turned off", before researchers could turn on their ability to become the new type of cell (cardiac).

But when study leader Rupa Sridharan, a professor of cell and regenerative biology at WID who studies the epigenetics of cell fate, began to examine single cells at a time, a technique known as scRNA-seq, her research team found that individual cells can activate properties of pluripotency without shutting down their differentiated features. In other words, a skin cell doesn't have to completely give up being a skin cell before it can begin the journey to becoming a cardiac cell.

Sridharan's team worked with algorithms developed by co-author Sushmita Roy, professor of biostatistics and medical informatics at WID, to perform the analyses. Roy is an expert in using statistical computational methods to identify regulatory gene networks, the collection of genes and the molecules that modify them that interact during development, cell differentiation, and in response to environmental clues.

"scRNA-seq is revolutionizing biology and is opening up a lot of opportunities to gain a high-resolution view of gene regulatory networks," says Roy.

The insight allowed the research team to spot differences emerging between individual cells, which Roy says is only the beginning. The tool can be applied to other, similar biological questions, such as understanding how functional cells become tumorous.

"There is a lot of room to develop the right type of computational tools to fully unlock the potential of these single-cell RNA-seq datasets," she says.

Meanwhile, Sridharan says that cells that can turn on pluripotency without shutting off their differentiated features may be good candidates for completing the transition. Focusing on such cells may be a path to greater efficiency.

Her lab has already had success using drugs that help overcome barriers to efficient reprogramming by modulating signaling and other gene regulation pathways. These include a new cocktail of small molecules that can jump-start the cell cycle in iPS cells, helping them arrive more quickly at their new fates. The study finds this can increase the success rate to around 40 percent and shorten the time scale of induced pluripotency.

Sridharan says that adding molecules that down-regulate differentiation features could further improve efficiency, though the study did not test this. Profiling the epigenome at the single-cell level will allow her to determine which genes are poised to change expression before that expression even begins.

Roy's algorithms also gave insight into how the regulatory networks change as the chemical cocktail changes. Identifying what small molecules to add next may be the key to unlocking further gains in efficiency. By combining laboratory and computational tools, Sridharan asks: "Can we rationally come up with what that molecule should be?" The answer might shape the future of regenerative therapies and precision medicine.

PRINCETON, N.J.--It's a classic policy dispute: How much should the current generation invest in reducing carbon emissions for the benefit of future generations?

A study published in Nature Communications helps answer this question by quantifying whether reducing carbon emissions -- which will have global benefits in the future -- also improves air quality now. Preventing many of the human health burdens that result from air pollution would be a powerful positive incentive to act sooner than later.

The study, which debuts a new climate policy model developed by Princeton University researchers and others, reports it is economically sound to quickly and dramatically cut greenhouse gas emissions given the immediate and significant human health benefits. The findings also support the climate targets prescribed by the Paris Climate Agreement in cost-benefit terms.

The model combines the cost of reducing emissions with the potential health 'co-benefits' or synergies of climate policy; these co-benefits have traditionally been excluded in the cost-benefit models that estimate how much the world should pay to reduce carbon emissions. When put together, the researchers find immediate net benefits globally from climate policy investments.

"Increasingly, we are finding that is important to consider public health impacts in analyses of climate change decision-making. We've built these considerations directly into this new model to see how the cost-benefit calculation changes when these impacts are accounted for. If we include the health benefits, the model tells use to reduce our emissions much more quickly than it would otherwise," said lead co-author Noah Scovronick, of Emory University, who worked on the model while at Princeton's Woodrow Wilson School of Public and International Affairs.

The results provide an economic vindication of the Paris Agreement targets for limiting temperature rise: If improved air quality and better health are included in the analysis, then a target of 2 degrees Celsius (or 3.6 degrees Fahrenheit) is economically defensible. This is because the health benefits resulting from air pollution reductions significantly outweigh any near-term costs, especially in developing regions. Prior economic studies on this issue did not support such a strict climate target.

"The climate problem has several features that make it particularly difficult to solve," said Marc Fleurbaey, Robert E. Kuenne Professor in Economics and Humanistic Studies and professor of public affairs and the University Center for Human Values. "Here, we show that accounting for the human health dimension alleviates many of these difficulties: Health benefits begin immediately, occur near where emissions are reduced, and accrue mainly in developing regions with less historical responsibility for climate change. The finding that climate policy may not in fact entail an intergenerational trade-off could completely change the framing of the debate."

Their new modeling framework for analyzing CO2 policy incorporates the costs and benefits of reducing air pollutant emissions. In particular, the environmental impacts from aerosols -- which result from air pollutant emissions -- have never been fully incorporated into this type of modeling. This is important for two reasons. On the one hand, reducing aerosol pollution is good for human health. One the other hand, however, aerosols act to cool the earth and thus counterbalance some of the warming generated by greenhouse gases; this beneficial effect is lost when air pollutant emissions are reduced. The researchers included both of these opposing effects in their framework.

When all of the benefits and harms are taken into account, the researchers see immediate net benefits globally, both in health and economic terms. In particular, the global health benefits from this climate policy could reach trillions of dollars annually, but their magnitude will depend somewhat on air quality policies that nations adopt independently of climate change. The team found the strongest potential near-term health benefits in China and India.

"Some developing regions have been understandably reluctant to invest their limited resources in reducing emissions," said Scovronick. "This and other studies demonstrate that many of these same regions are likely to gain most of the health co-benefits, which may add incentive for them to adopt stronger climate policies."

Potentially life-saving cancer risk assessment tools are being widely underused by general practices across the UK, according to new research.

A team of experts from the University of Exeter's Medical School has designed a set of risk assessment tools - which can predict the likelihood of undiagnosed cancer based on patients' symptoms, test results and other clinical information. Now, new NIHR-funded research has reviewed how well used the tools are within health practices.

In a survey of 476 GPs working in 277 general practices in the UK, the researchers discovered that the tools are only available for use in one-third of practices, although this should increase as the tools are integrated into more IT systems in the future. Crucially, the survey found that the tools are only likely to be used in around a half of those practices that have access.

This is important because, in the UK, one in three people in the UK will develop cancer during their lifetime. Although cancer survival rates in the UK have improved in the past 15 years, they still lag behind average European figures.

Earlier diagnosis is considered to be one of the main ways to improve UK survival; for example, more than 9 out of 10 people will survive bowel cancer if diagnosed at stage 1, as opposed to just 4 out of 10 when diagnosed at stage 4. This is where the risk assessment tools may play an important role - helping GPs to identify which patients with signs and symptoms suggestive of cancer should be referred for investigation according to national and local guidelines.

In response to their findings, the researchers have called for a new and sustained training drive for GPs, so that the tools are used habitually, and effectively.

The training should include the careful recording and coding of patients' symptoms, to maximise their potential in the early diagnosis of cancer, the team suggest.

The research is published in the British Journal of General Practice on Wednesday, May 8th 2019.

Dr Sarah Price, a Research Fellow at the University of Exeter Medical School and lead author of the study said: "The tools are potentially a useful resource for GPs, helping them to assess which of their patients should be sent for testing because they might be harbouring an undiagnosed cancer. We need to carry out further research and work with GPs to find out how the tools can be integrated into the often time-pressured consultations between GPs and their patients."

Professor Willie Hamilton, of the University of Exeter Medical School, a practising GP and co-author of the survey added: "We know that some of the UK's poor cancer outcomes relate to delays in diagnosis. The study shows that there is much scope for cancer tools to be used more. We are launching a major trial of them in 530 practices in the second half of this year."

Availability and use of cancer decision-support tools: a cross-sectional survey of UK primary care is published in the British Journal of General Practice on Wednesday, May 8th 2019.