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Researchers turn powerful, viscous disinfectants into breathable mist for the first time

A team of engineers and physicians in San Diego have developed a device that diffuses potent disinfectants for airborne delivery. Notably, the device works on a range of disinfectants that have never been atomized before, such as Triethylene glycol, or TEG.

In a study published in the August issue of Applied Microbiology and Biotechnology, the team used the device to atomize disinfectants onto environmental surfaces contaminated with bacteria and showed that it effectively eliminated 100 percent of bacteria that commonly cause hospital-acquired infections. In addition, atomized bleach solution, ethanol and TEG completely eliminated highly multi-drug resistant strains of bacteria including K. pneumoniae.

“Cleaning and disinfecting environmental surfaces in healthcare facilities is a critical infection prevention and control practice,” said Dr. Monika Kumaraswamy, a physician scientist at the University of California San Diego, hospital epidemiologist at the VA San Diego Healthcare System and corresponding author on the paper. “This device will make it much easier to keep hospital rooms clean.”

Researchers point out that one in 25 patients who checked into hospitals in 2011 (the last year for which data was available) had to prolong their stay because of healthcare-related infections developed within the hospital.

The technology has broader potential applications too. It could be used to deliver a whole new class of medicines to patients via inhalers.

“Our goal is to make injectable treatments inhalable,” said James Friend, a professor of mechanical engineering at the UC San Diego Jacobs School of Engineering and one of the paper’s authors.

Researchers built the device using off-the-shelf smartphone components that produce acoustic waves. In phones, these parts are used mainly to filter wireless cellular signals and identify and filter voice and data information.

In this study, researchers used the smartphone components to generate sound waves at extremely high frequencies — ranging from 100 million to 10 billion hertz — in order to create fluid capillary waves, which in turn emit droplets and generate mist. This process is called atomization.

Currently, fluids can be atomized by mechanical means like in perfume and cologne sprayers, or by using ultrasound. But these methods either don’t work well with viscous fluids, require too much power, or break down some of the fluids’ active ingredients. They also require expensive equipment.

The technology used in this paper doesn’t have these drawbacks. That’s because the smart phone components use Lithium Niobate, or LN, a material that produces more energy efficient and more reliable ultrasonic vibrations. As a result, the device can atomize even the most viscous fluids into a fine mist that can drift in the air for more than an hour.

The device was built by Friend’s research group and tested in the laboratory of Dr. Victor Nizet at the UC San Diego School of Medicine, in experiments led by Kumaraswamy.

Although the device worked well on pneumonia-causing bacteria and on various multi-drug resistant strains of other pathogens, atomized TEG did not eliminate MRSA, much to the researchers’ surprise. “People told us TEG kills everything,” Friend said. “Well that’s just not true: in atomized droplet form, it was not all that effective at doing away with MRSA.”

Researchers are now working on building an updated prototype to use in a hospital setting, a process that they expect to take one or two years. The device also could be used in airports, airplanes and in public transportation during flu season, for example.

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Fecal bacteria contaminated surface water after Hurricane Harvey

Hurricane Harvey was an unprecedented rain event that delivered five consistent days of flooding and storms to Texas last August. Now, research from UTSA Assistant Professor Vikram Kapoor in civil and environmental engineering has substantiated that the storm caused high levels of fecal contamination to be introduced into waterways draining into the Gulf of Mexico and impairing surface water quality.

Kapoor’s research assessed microbial contaminants in southeast and southcentral Texas waterways following Hurricane Harvey. His work was supported by a Rapid Response Research grant from the National Science Foundation.

“The research we conducted in the Guadalupe River after Hurricane Harvey substantiates that the large number of sewage overflows and storm-water runoff that occurred during Hurricane Harvey flooding introduced high levels of fecal bacteria into environmental waters.”

After 800 wastewater treatment plants reported spills from flooding and more than two million pounds of contaminants were released into the environment, the study reports that the sewage overflows posed a risk to human and environmental health via waterborne disease outbreaks, deterioration of recreational and drinking water quality and the degradation of aquatic ecology. The report further confirms how hurricanes and large storms play a significant role in the transport of water contaminants across environmental waters.

Kapoor selected the Guadalupe River because it is an important drinking water source for several cities and is used in part for recreational activities. The river runs from Kerr County, Texas to the San Antonio Bay in the Gulf of Mexico. Excessive rainfall from Hurricane Harvey resulted in major flooding over the Guadalupe River in Victoria, Texas. The river crested at 32 feet, around 10 feet above flood stage.

Notably, all initial water samples collected from the flooded regions of the Guadalupe River by Kapoor and his students contained E. coli and enterococci concentrations above the regulatory level for contact recreational waters. The UTSA study suggested future studies are needed to explore relationships between human health and human-associated fecal marker levels in recreational waters impacted by sewage, treated effluents and human feces. The findings of this initial study will serve as the baseline information for follow-on studies to monitor existing and emerging public health risks to residents of Texas and potential long-term environmental impacts on the water resources in the impacted regions.

During Spring Break 2018, officials published alerts concerning fecal matter at some Texas beaches. While Kapoor says it’s too early to tell if those beaches were impacted as a result of Hurricane Harvey, he notes that he and his students observed elevated levels of fecal bacteria at flooded sites even two to three months after Harvey.

The UTSA environmental engineering professor is hopeful that his research on the short and long-term effects of Hurricane Harvey’s flooding will lead to the development of a predictive framework to assess wastewater contamination following severe flooding.

“We are conducting research at UTSA on the mobilization of microbial contaminants and the length of time they persist in affected areas,” he said. “The results will improve how scientists evaluate the human health impacts of contaminants mobilized and deposited by floodwaters.”

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Heatwave deaths will rise steadily by 2080 as globe warms up

If people cannot adapt to future climate temperatures, deaths caused by severe heatwaves will increase dramatically in tropical and subtropical regions, followed closely by Australia, Europe and the United States, a global new Monash-led study shows.

Published today in PLOS Medicine, it is the first global study to predict future heatwave-related deaths and aims to help decision makers in planning adaptation and mitigation strategies for climate change.

Researchers developed a model to estimate the number of deaths related to heatwaves in 412 communities across 20 countries for the period of 2031 to 2080.

The study projected excess mortality in relation to heatwaves in the future under different scenarios characterised by levels of greenhouse gas emissions, preparedness and adaption strategies and population density across these regions.

Study lead and Monash Associate Professor Yuming Guo said the recent media reports detailing deadly heatwaves around the world highlight the importance of the heatwave study.

“Future heatwaves in particular will be more frequent, more intense and will last much longer,” Associate Professor Guo said.

“If we cannot find a way to mitigate the climate change (reduce the heatwave days) and help people adapt to heatwaves, there will be a big increase of heatwave-related deaths in the future, particularly in the poor countries located around the equator.”

A key finding of the study shows that under the extreme scenario, there will be a 471 per cent increase in deaths caused by heatwaves in three Australian cities (Brisbane, Sydney and Melbourne) in comparison with the period 1971-2010.

“If the Australia government cannot put effort into reducing the impacts of heatwaves, more people will die because of heatwaves in the future,” Associate Professor Guo said.

The study comes as many countries around the world have been affected by severe heatwaves, leaving thousands dead and tens of thousands more suffering from heatstroke-related illnesses. The collective death toll across India, Greece, Japan and Canada continues to rise as the regions swelter through record temperatures, humidity, and wildfires. Associate Professor Antonio Gasparrini, from the London School of Hygiene & Tropical Medicine and study co-author, said since the turn of the century, it’s thought heatwaves have been responsible for tens of thousands of deaths, including regions of Europe and Russia.

“Worryingly, research shows that is it highly likely that there will be an increase in their frequency and severity under a changing climate, however, evidence about the impacts on mortality at a global scale is limited,” Associate Professor Gasparrini said.

“This research, the largest epidemiological study on the projected impacts of heatwaves under global warming, suggests it could dramatically increase heatwave-related mortality, especially in highly-populated tropical and sub-tropical countries. The good news is that if we mitigate greenhouse gas emissions under scenarios that comply with the Paris Agreement, then the projected impact will be much reduced.”

Associate Professor Gasparrini said he hoped the study’s projections would support decision makes in planning crucial adaptation and mitigation strategies for climate change.

In order to prevent mass population death due to increasingly severe heatwaves, the study recommends the following six adaption interventions, particularly significant for developing countries and tropical and subtropical regions:

  • Individual: information provision, adverting
  • Interpersonal: Information sharing; communication; persuasive arguments; counselling; peer education
  • Community: Strengthening community infrastructure; encouraging community engagement; developing vulnerable people group; livelihoods; neighbourhood watch
  • Institutional: Institutional policies; quality standards; formal procedures and regulations; partnership working
  • Environmental: Urban planning and management; built environment; planting trees; public available drink water; house quality
  • Public policy: Improvement of health services; poverty reduction; redistribution of resources; education; heatwave-warning system.

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Differences in social status and politics encourage paranoid thinking

Differences in social status and political belief increase paranoid interpretations of other people’s actions, finds a new UCL experimental study.

Paranoia is the tendency to assume other people are trying to harm you when their actual motivations are unclear, and this tendency is increased when interacting with someone of a higher social status or opposing political beliefs, according to the study published today in Royal Society Open Science.

“Being alert to social danger is key to our survival, but our results suggest social difference alone encourages us to think that the other person wants to harm us,” said the study’s senior author, Professor Nichola Raihani (UCL Psychology & Language Sciences).

“Intense paranoia is also a symptom of mental ill health, and is more common among people who perceive themselves to have low social rank. We believe our findings could shed light on why paranoia is more common in those who are struggling on the social ladder and excluded by society,” she added.

For the study, 2,030 people participated in an online experiment where they were paired with another person and given a sum of money. Ahead of the experiment, all participants had reported their typical levels of paranoid thinking by filling out a questionnaire, as well as their own perceived social status and their political affiliation along the liberal-conservative spectrum. They were then paired with someone from a higher, lower or similar social status, or with someone who had similar or opposing political beliefs.

In each pair, one person got to decide whether to split the money 50-50 or to keep it all for themselves. The other person was then asked to rate how much they thought the decision was motivated by the decider’s self-interest, and how much the decision was likely motivated by the decider wanting to deny them any of the prize — a measure of perceived harmful intent. The roles were then swapped with a new sum of money.

People who were paired with someone with a higher social status or with different political beliefs more frequently assumed their partner’s decision had been motivated by wanting to cause them harm. In contrast, social difference did not affect how often people assumed their partner was motivated by self-interest.

Researchers also found that the over-perception of other people’s harmful intentions occurred at the same rate, regardless of whether participants already had heightened levels of paranoid thinking.

“Our findings suggest that people who struggle with high levels of paranoia are equally well-tuned to social difference despite sometimes seeming that they misperceive the social world. This research may help us understand how exclusion and disadvantage fuel some of the most severe mental health problems,” said co-author Dr Vaughan Bell (UCL Psychiatry).

The researchers were funded by the Royal Society and Wellcome.

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Sunscreen chemicals in water may harm fish embryos

For most people, a trip to the beach involves slathering on a thick layer of sunscreen to protect against sunburn and skin cancer. However, savvy beachgoers know to reapply sunscreen every few hours because it eventually washes off. Now researchers, reporting in ACS’ journal Environmental Science & Technology, have detected high levels of sunscreen chemicals in the waters of Shenzhen, China, and they also show that the products can affect zebrafish embryo development.

A painful sunburn can ruin a vacation, and too much sun can also lead to more serious problems like premature skin aging and melanoma. Therefore, manufacturers have added ultraviolet (UV) filters to many personal care products, including sunscreens, moisturizers and makeup. Scientists have detected these substances in the environment, but most studies have concluded that individual sunscreen chemicals are not present at high-enough levels to harm people or animals. Kelvin Sze-Yin Leung wondered if combinations of UV filters may be more harmful than individual compounds, and whether these chemicals could have long-term effects that previous studies hadn’t considered.

Leung and his team began by analyzing the levels of nine common UV filters in surface waters of Shenzhen, China — a rapidly growing city with more than 20 popular recreational beaches. They found seven of the nine chemicals in Shenzhen waters, including public beaches, a harbor and, surprisingly, a reservoir and tap water. Next, the researchers moved to the lab where they fed zebrafish, a common model organism, brine shrimp that had been exposed to three of the most prevalent chemicals, alone or in mixtures. Although the adult fish had no visible problems, their offspring showed abnormalities. These outcomes were mostly observed for longer-term exposures (47 days) and elevated levels of the chemicals (higher than what is likely to occur in the environment.) The effects of different UV filters and mixtures of these substances varied in often-unpredictable ways, suggesting that further studies are needed to determine how these chemicals impact living systems.

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Lung cancer mortality rates among women projected to increase by over 40 percent by 2030

The global age-standardized lung cancer mortality rate among women is projected to increase by 43 percent from 2015 to 2030, according to an analysis of data from 52 countries. The global age-standardized breast cancer mortality rate is projected to decrease by 9 percent in the same time frame.

While previous work has focused on projections in lung and breast cancer mortality among women in a single country or continent, few studies have estimated trends in mortality caused by these two common cancers on a global scale, noted Martínez-Sánchez.

In this study, Martínez-Sánchez and colleagues analyzed breast and female lung cancer mortality data from the World Health Organization (WHO) Mortality Database from 2008 to 2014. For inclusion in the study, countries must have reported data for at least four years between 2008 and 2014 and must have a population greater than 1 million. Fifty-two countries fulfilled these criteria: 29 from Europe; 14 from the Americas; seven from Asia; and two from Oceania. Lung and breast cancer age-standardized mortality rates in women, reported as per 100,000 person years, were calculated for each country based on the WHO World Standard Population, which allows for the comparison of countries with different age distributions, thereby eliminating age as a confounding variable in the projected rates.

Globally, among women, the mortality rate for lung cancer is projected to increase from 11.2 in 2015 to 16.0 in 2030; the highest lung cancer mortality rates in 2030 are projected in Europe and Oceania, while the lowest lung cancer mortality rates in 2030 are projected in America and Asia. Only Oceania is predicted to see a decrease in lung cancer mortality, which is projected to fall from 17.8 in 2015 to 17.6 in 2030.

“Different timelines have been observed in the tobacco epidemic across the globe,” said Martínez-Sánchez. “This is because it was socially acceptable for women to smoke in the European and Oceanic countries included in our study many years before this habit was commonplace in America and Asia, which reflects why we are seeing higher lung cancer mortality rates in these countries.”

Globally, the mortality rate for breast cancer is projected to decrease from 16.1 in 2015 to 14.7 in 2030. The highest breast cancer mortality rate is predicted in Europe with a decreasing trend overall, while the lowest breast cancer mortality rate is predicted in Asia with an increasing trend overall.

“Breast cancer is associated with many lifestyle factors,” Martínez-Sánchez explained. “We are seeing an increase in breast cancer mortality in Asia because this culture is adapting a Westernized lifestyle, which often leads to obesity and increased alcohol intake, both of which can lead to breast cancer. On the other hand, we are witnessing a decrease in breast cancer mortality in Europe, which may be related to the awareness of breast cancer among this population, leading to active participation in screening programs and the improvement of treatments.”

Compared to middle-income countries, high-income countries have the highest projected age-standardized mortality rates for both lung and breast cancer in 2030. However, high-income countries are more likely to have decreasing breast cancer mortality rates. Furthermore, the first to witness lung cancer mortality rates surpass breast cancer mortality rates are mostly developed countries, noted Martínez-Sánchez.

“This research is particularly important because it provides evidence for health professionals and policymakers to decide on global strategies to reduce the social, economic, and health impacts of lung cancer among women in the future,” said Martínez-Sánchez.

Limitations of the study include the assumption that recent trends in lung and breast cancer mortality will continue for the next two decades; however, certain habits, such as switching from conventional cigarettes to electronic cigarettes may alter lung cancer mortality trends, Martínez-Sánchez said. Future screening technology and therapeutics may lower mortality rates, he added. Additionally, due to small population size and lack of data, no countries from Africa were included in this study.

 This study was sponsored by the Ministry of Universities and Research of the Government of Catalonia. 

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On-chip optical filter processes wide range of light wavelengths

MIT researchers have designed an optical filter on a chip that can process optical signals from across an extremely wide spectrum of light at once, something never before available to integrated optics systems that process data using light. The technology may offer greater precision and flexibility for designing optical communication and sensor systems, studying photons and other particles through ultrafast techniques, and in other applications.

Optical filters are used to separate one light source into two separate outputs: one reflects unwanted wavelengths — or colors — and the other transmits desired wavelengths. Instruments that require infrared radiation, for instance, will use optical filters to remove any visible light and get cleaner infrared signals.

Existing optical filters, however, have tradeoffs and disadvantages. Discrete (off-chip) “broadband” filters, called dichroic filters, process wide portions of the light spectrum but are large, can be expensive, and require many layers of optical coatings that reflect certain wavelengths. Integrated filters can be produced in large quantities inexpensively, but they typically cover a very narrow band of the spectrum, so many must be combined to efficiently and selectively filter larger portions of the spectrum.

Researchers from MIT’s Research Laboratory of Electronics have designed the first on-chip filter that, essentially, matches the broadband coverage and precision performance of the bulky filters but can be manufactured using traditional silicon-chip fabrication methods.

“This new filter takes an extremely broad range of wavelengths within its bandwidth as input and efficiently separates it into two output signals, regardless of exactly how wide or at what wavelength the input is. That capability didn’t exist before in integrated optics,” says Emir Salih Magden, a former PhD student in MIT’s Department of Electrical Engineering and Computer Science (EECS) and first author on a paper describing the filters published today in Nature Communications.

Paper co-authors along with Magden, who is now an assistant professor of electrical engineering at Koç University in Turkey, are: Nanxi Li, a Harvard University graduate student; and, from MIT, graduate student Manan Raval; former graduate student Christopher V. Poulton; former postdoc Alfonso Ruocco; postdoc associate Neetesh Singh; former research scientist Diedrik Vermeulen; Erich Ippen, the Elihu Thomson Professor in EECS and the Department of Physics; Leslie Kolodziejski, a professor in EECS; and Michael Watts, an associate professor in EECS.

Dictating the flow of light

The MIT researchers designed a novel chip architecture that mimics dichroic filters in many ways. They created two sections of precisely sized and aligned (down to the nanometer) silicon waveguides that coax different wavelengths into different outputs.

Waveguides have rectangular cross-sections typically made of a “core” of high-index material — meaning light travels slowly through it — surrounded by a lower-index material. When light encounters the higher- and lower-index materials, it tends to bounce toward the higher-index material. Thus, in the waveguide light becomes trapped in, and travels along, the core.

The MIT researchers use waveguides to precisely guide the light input to the corresponding signal outputs. One section of the researchers’ filter contains an array of three waveguides, while the other section contains one waveguide that’s slightly wider than any of the three individual ones.

In a device using the same material for all waveguides, light tends to travel along the widest waveguide. By tweaking the widths in the array of three waveguides and gaps between them, the researchers make them appear as a single wider waveguide, but only to light with longer wavelengths. Wavelengths are measured in nanometers, and adjusting these waveguide metrics creates a “cutoff,” meaning the precise nanometer of wavelength above which light will “see” the array of three waveguides as a single one.

In the paper, for instance, the researchers created a single waveguide measuring 318 nanometers, and three separate waveguides measuring 250 nanometers each with gaps of 100 nanometers in between. This corresponded to a cutoff of around 1,540 nanometers, which is in the infrared region. When a light beam entered the filter, wavelengths measuring less than 1,540 nanometers could detect one wide waveguide on one side and three narrower waveguides on the other. Those wavelengths move along the wider waveguide. Wavelengths longer than 1,540 nanometers, however, can’t detect spaces between three separate waveguides. Instead, they detect a massive waveguide wider than the single waveguide, so move toward the three waveguides.

“That these long wavelengths are unable to distinguish these gaps, and see them as a single waveguide, is half of the puzzle. The other half is designing efficient transitions for routing light through these waveguides toward the outputs,” Magden says.

The design also allows for a very sharp roll-off, measured by how precisely a filter splits an input near the cutoff. If the roll-off is gradual, some desired transmission signal goes into the undesired output. Sharper roll-off produces a cleaner signal filtered with minimal loss. In measurements, the researchers found their filters offer about 10 to 70 times sharper roll-offs than other broadband filters.

As a final component, the researchers provided guidelines for exact widths and gaps of the waveguides needed to achieve different cutoffs for different wavelengths. In that way, the filters are highly customizable to work at any wavelength range. “Once you choose what materials to use, you can determine the necessary waveguide dimensions and design a similar filter for your own platform,” Magden says.

Sharper tools

Many of these broadband filters can be implemented within one system to flexibly process signals from across the entire optical spectrum, including splitting and combing signals from multiple inputs into multiple outputs.

This could pave the way for sharper “optical combs,” a relatively new invention consisting of uniformly spaced femtosecond (one quadrillionth of a second) pulses of light from across the visible light spectrum — with some spanning ultraviolet and infrared zones — resulting in thousands of individual lines of radio-frequency signals that resemble “teeth” of a comb. Broadband optical filters are critical in combining different parts of the comb, which reduces unwanted signal noise and produces very fine comb teeth at exact wavelengths.

Because the speed of light is known and constant, the teeth of the comb can be used like a ruler to measure light emitted or reflected by objects for various purposes. A promising new application for the combs is powering “optical clocks” for GPS satellites that could potentially pinpoint a cellphone user’s location down to the centimeter or even help better detect gravitational waves. GPS works by tracking the time it takes a signal to travel from a satellite to the user’s phone. Other applications include high-precision spectroscopy, enabled by stable optical combs combining different portions of the optical spectrum into one beam, to study the optical signatures of atoms, ions, and other particles.

In these applications and others, it’s helpful to have filters that cover broad, and vastly different, portions of the optical spectrum on one device.

“Once we have really precise clocks with sharp optical and radio-frequency signals, you can get more accurate positioning and navigation, better receptor quality, and, with spectroscopy, get access to phenomena you couldn’t measure before,” Magden says.

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Polymer pill proves it can deliver

Selecting the right packaging to get precious cargo from point A to point B can be a daunting task at the post office. For some time, scientists have wrestled with a similar set of questions when packaging medicine for delivery in the bloodstream: How much packing will keep it safe? Is it the right packing material? Is it too big? Is it too heavy? Researchers from Drexel University have developed a new type of container that seems to be the perfect fit for making the delivery.

Intravenous medication has taken important leaps in recent years as a way of directly targeting ailments where they are occurring inside the body. But getting the medicine through the bloodstream to the right place and releasing it at the right time is no easy task. The body is designed to detect and eliminate foreign objects, so successfully designing a vessel for targeted drug delivery requires equal parts engineering and cunning.

“Delivery vessels have traditionally been designed to avoid recognition by the immune system by mimicking naturally occurring materials in the body, such as cells or liposomes,” said Christopher Li, PhD, a materials science professor in Drexel’s College of Engineering. “But the problem with the previously reported artificial carriers is that they’re not always durable enough to get to the far reaches of the body.”

Li and Hao Cheng, PhD, an assistant professor in the College of Engineering lead a group of researchers who have been developing a polymer crystal casing for intravenous medicine delivery. Their work, which was recently published in the journal Nature Communications shows how these “crystalsomes,” designed to be durable enough for long, intravenous journeys, can outlast current artificial nanoparticle packaging — which means doctors can use it to directly treat maladies in the body, with precisely the right amount of medication.

“Crystalsomes structurally mimic the classical liposome and polymersomes used for drug delivery, yet mechanically they are more robust thanks to their single crystal-like shell,” Li said.

In blood circulation and biodistribution experiments, Li’s polymer crystalsomes have a 24-hour half-life and can last in the bloodstream for more than 96 hours — figures that far exceed current injectable medication.

“Crystalsomes are closely sealed so that medication will not be released until it reaches the target sites. Thus medication can be delivered in higher doses, as desired, to afflictions in the body, without causing severe side-effects associated with the early release of the medicine,” Li said. “And a more direct intravenous delivery means that treatments are likely to be more effective.”

Li’s group combined its unique work on growing crystal spheres and self-assembled nanobrushes to produce this special capsule that is just thick enough to safely encase the medicine, and also features an array of polymer strands that can ward off the proteins that flag foreign bodies for removal.

The method for creating the crystalsomes, which Li’s Soft Materials Lab initially developed in 2016, looks something like combining oil and water to create suspended liquid beads. In this application, the beads encapsulate two types of polymer strands that, when cooled, condense into the solid, egg shell-like spherical crystalsome, protecting the yolk-like cargo inside.

While one set of polymers, called poly L-lactide acid or PLLA, are drawing together to form the corrugated casing of the sphere, the other variety, poly ethylene glycol or PEG, coming to attention like whiskers on its surface. PEG polymers are known to prevent proteins from attaching to solid surfaces, so the uniform distribution of these polymers on the outside of the crystalsome prevent it from being flagged by the proteins of the immune system as a bodily invader.

“Taken together, these characteristics give the crystalsome its superior staying power in the bloodstream,” said Cheng, whose research group specializes in engineering molecules for intravenous drug delivery.

The discovery provides a strategy for producing long-circulating nanomaterials, which could lead to a new class of polymer nanoparticle carriers for drug delivery and gene therapy, according to the researchers.

“The ingenious, curved, polymer crystal nanocapsules reported here remain robust while circulating in the blood, a potentially important feature for delivering medications and gene therapies,” said Andrew Lovinger, the materials research program officer who oversaw National Science Foundation funding of the work. “NSF is proud to have supported this important research, which integrates the agency’s missions to promote the progress of science as well as contribute to advancing the nation’s health.”

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Women with polycystic ovary syndrome more likely to have a child with autism

Women with polycystic ovary syndrome (PCOS) are more likely than other women to have an autistic child, according to an analysis of NHS data carried out by a team at Cambridge University’s Autism Research Centre. The research is published today in the journal Translational Psychiatry.

PCOS affects about one in ten women and is caused by elevated levels of the hormone testosterone. It is associated with fluid-filled sacs (called follicles) in the ovaries, and with symptoms such as delayed onset of puberty, irregular menstrual cycles, and excess bodily hair.

Autism is a condition characterized by difficulties in social interaction and communication alongside unusually narrow interests, a strong preference for predictability, and difficulties adjusting to unexpected change. Some autistic people also have learning difficulties and delayed language, and many have sensory hyper-sensitivity. The signs of autism are evident in childhood even if the diagnosis is not made until later, and occurs in about 1% of the population.

The research team previously published work in 2015 which showed that before they are born, autistic children have elevated levels of ‘sex steroid’ hormones (including testosterone) which ‘masculinise’ the baby’s body and brain. The discovery that prenatal sex steroid hormones are involved in the development of autism is one possible explanation for why autism is diagnosed more often in boys.

The scientists wondered where these elevated sex steroid hormones were coming from, one possible source being the mother. If she had higher levels of testosterone than usual, as is the case in women with PCOS, then some of the hormone might cross the placenta during pregnancy, exposing her unborn baby to more of this hormone, and changing the baby’s brain development.

Using anonymous data from a large database of GP health records, the study looked at 8,588 women with PCOS and their first-born children, compared to a group of 41,127 women without PCOS. The team found that, even after taking into account other factors (like maternal mental health problems or complications during pregnancy), women with PCOS had a 2.3% chance of having an autistic child, compared with the 1.7% chance for mothers without PCOS.

The team stressed that the likelihood of having an autistic child is still very low, even among women with PCOS — but finding this link provides an important clue in understanding one of the multiple causal factors in autism.

The team presented their findings at the International Meeting for Autism Research in 2016, and their findings were replicated in a Swedish study in the same year, adding to the reliability of the result.

The team also conducted two other studies using the same data and found that autistic women were more likely to have PCOS, and women with PCOS were more likely to have autism themselves. This strongly suggests that these two conditions are linked, probably because they both share elevated sex steroid hormone levels.

Adriana Cherskov, the Master’s student who analysed the data, and who is now studying medicine in the US, said: “This is an important piece of new evidence for the theory that autism is not only caused by genes but also by prenatal sex steroid hormones such as testosterone.”

Professor Simon Baron-Cohen, Director of the Autism Research Centre, who supervised the research, said: “This new research is helping us understand the effects of testosterone on the developing fetal brain, and on the child’s later behaviour and mind. These hormonal effects are not necessarily independent of genetic factors, as a mother or her baby may have higher levels of the hormone for genetic reasons, and testosterone can affect how genes function.”

Dr Carrie Allison who co-supervised the research, said: “We need to think about the practical steps we can put in place to support women with PCOS as they go through their pregnancies. The likelihood is statistically significant but nevertheless still small, in that most women with PCOS won’t have a child with autism, but we want to be transparent with this new information.”

Dr Rupert Payne from the University of Bristol Centre for Academic Primary Care, a GP and the expert on the team in using GP health record data for this type of research, said: “Autism can have a significant impact on a person’s wellbeing, and on their parents, and many autistic people have significant health, social care and educational special needs. This is an important step in trying to understand what causes autism. It is also an excellent example of the value of using anonymous routine healthcare data to answer vital medical research questions.”

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Tech takes on cigarette smoking

Researchers at Case Western Reserve University are using wearable sensor technology to develop an automatic alert system to help people quit smoking.

The smart-phone app, initially limited to android-based operating systems, automatically texts 20- to 120-second video messages to smokers when sensors detect specific arm and body motions associated with smoking.

There is no shortage of products or programs — from nicotine gum to hypnosis — to help people stop smoking. More recently, wearable technology has gained popularity in the fight against addiction.

But the mobile alert system Case Western Reserve researchers are testing may be the first that combines:

  • an existing online platform with mindfulness training and a personalized plan for quitting; * two armband sensors to detect smoking motions, a technology that demonstrated more than 98-percent accuracy in differentiating “lighting up” from other similar motions. (That compares to 72-percent accuracy in systems using a single armband);
  • and a personalized text-messaging service that reminds the user of either their own plan to quit, or sends video messages that stress the health and financial benefits of quitting.

Collaborative effort

The system was conceived, developed and tested over the course of the last year by a team of Electrical Engineering and Computer Science researchers at the Case School of Engineering and a high school intern in collaboration with a clinical psychologist at the Case Western Reserve School of Medicine.

A paper detailing the system and reporting early findings on a group of 10 users was published in a July edition of Smart Health. The researchers said most previous studies have relied on smokers self-reporting how often they smoked, while the Case Western Reserve system more accurately tracked smoking activity based on the sensors.

“We’ve been able to differentiate between a single motion, which could be confused with eating or drinking, and a sequence of motions more clearly linked to the act of smoking a cigarette,” said Ming-Chun Huang, an assistant electrical engineering and computer science professor who led the technical aspect of the study.

The collaboration to develop a technology-enhanced, and personalized mobile-smoking cessation system started after a conversation last summer between Huang, who was looking for a new project for his students, and Monica Webb Hooper of the Case Comprehensive Cancer Center, who was seeking new ways to help her clients break the habit.

“The field of tobacco control has really adopted mobile technologies because many people won’t come in for therapy,” said Webb Hooper, who has been working on interventions for nearly two decades.

“We were interested in translating one of our programs into a video-based mobile application, but the motion sensors made this even more amazing,” said Webb Hooper, who has extended the study to another 120 smokers — half using the program and a control group using a standard text messaging program without sensors or video messaging.

The addiction problem

Tobacco smoking is responsible for one of every five deaths in the United States, according to the Centers for Disease Control and Prevention. Other research has shown there are more than 7,000 chemicals in cigarettes, including carbon monoxide, hydrogen cyanide and nitrogen oxides in cigarette smoke.

Further, the National Cancer Institute reports that there are 69 known cancer-causing agents in tobacco smoke.

“Tobacco is the toughest of all addictions to overcome and cigarettes are one of the easiest drugs to become addicted to — all it takes is three (cigarettes) for some people,” Webb Hooper said. “And, neurologically, it’s harder to quit because we have more nicotine receptors in the brain. That’s why I’m so excited about this intervention.”