Culture

Black holes are known for their voracious appetites, binging on matter with such ferocity that not even light can escape once it's swallowed up.

Less understood, though, is how black holes purge energy locked up in their rotation, jetting near-light-speed plasmas into space to opposite sides in one of the most powerful displays in the universe. These jets can extend outward for millions of light years.

New simulations led by researchers working at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley have combined decades-old theories to provide new insight about the driving mechanisms in the plasma jets that allows them to steal energy from black holes' powerful gravitational fields and propel it far from their gaping mouths.

The simulations could provide a useful comparison for high-resolution observations from the Event Horizon Telescope, an array that is designed to provide the first direct images of the regions where the plasma jets form.

The telescope will enable new views of the black hole at the center of our own Milky Way galaxy, as well as detailed views of other supermassive black holes.

"How can the energy in a black hole's rotation be extracted to make jets?" said Kyle Parfrey, who led the work on the simulations while he was an Einstein Postdoctoral Fellow affiliated with the Nuclear Science Division at Berkeley Lab. "This has been a question for a long time."

Now a senior fellow at NASA Goddard Space Flight Center in Maryland, Parfrey is the lead author of a study, published Jan. 23 in Physical Review Letters, that details the simulations research.

The simulations, for the first time, unite a theory that explains how electric currents around a black hole twist magnetic fields into forming jets, with a separate theory explaining how particles crossing through a black hole's point of no return - the event horizon - can appear to a distant observer to carry in negative energy and lower the black hole's overall rotational energy.

It's like eating a snack that causes you to lose calories rather than gaining them. The black hole actually loses mass as a result of slurping in these "negative-energy" particles.

Computer simulations have difficulty in modeling all of the complex physics involved in plasma-jet launching, which must account for the creation of pairs of electrons and positrons, the acceleration mechanism for particles, and the emission of light in the jets.

Berkeley Lab has contributed extensively to plasma simulations over its long history. Plasma is a gas-like mixture of charged particles that is the universe's most common state of matter.

Parfrey said he realized that more complex simulations to better describe the jets would require a combination of expertise in plasma physics and the general theory of relativity.

"I thought it would be a good time to try to bring these two things together," he said.

Performed at a supercomputing center at NASA Ames Research Center in Mountain View, California, the simulations incorporate new numerical techniques that provide the first model of a collisionless plasma - in which collisions between charged particles do not play a major role - in the presence of a strong gravitational field associated with a black hole.

The simulations naturally produce effects known as the Blandford-Znajek mechanism, which describes the twisting magnetic fields that form jets, and a separate Penrose process that describes what happens when negative-energy particles are gulped down by the black hole.

The Penrose process, "even though it doesn't necessarily contribute that much to extracting the black hole's rotation energy," Parfrey said, "is possibly directly linked to the electric currents that twist the jets' magnetic fields."

While more detailed than some earlier models, Parfrey noted that his team's simulations are still playing catch-up with observations, and are idealized in some ways to simplify the calculations needed to perform the simulations.

The team intends to better model the process by which electron-positron pairs are created in the jets in order to study the jets' plasma distribution and their emission of radiation more realistically for comparison to observations. They also plan to broaden the scope of the simulations to include the flow of infalling matter around the black hole's event horizon, known as its accretion flow.

"We hope to provide a more consistent picture of the whole problem," he said.

Some people consider pufferfish, also known as fugu, a delicacy because of its unique and exquisite flavor, which is perhaps seasoned by knowledge that consumption of the fish could be deadly. Now, researchers have identified the major compounds responsible for the taste of pufferfish, minus the thrill of living dangerously. They report their results in ACS' Journal of Agricultural and Food Chemistry.

Pufferfish get their name from their ability to inflate to a much larger size when threatened by predators. But if that defense mechanism fails, the predator may not survive long after its meal: The liver, ovaries, eyes and skin of most species of pufferfish contain tetrodotoxin, a potent neurotoxin. Although specially trained chefs can prepare fugu that's safe to eat, Yuan Liu and colleagues wondered if they could reproduce the flavor of pufferfish without the life-threatening toxin.

The researchers analyzed the key taste-active compounds in Takifugu obscurus, a species of pufferfish found mainly in the East and South China Seas. First, the team ground up pufferfish muscle tissue and cooked, filtered and centrifuged it to produce a liquid pufferfish extract. They then analyzed the extract and found amounts of 28 potential taste compounds, such as free amino acids, nucleotides and inorganic ions. Taste tests with trained panelists revealed that 12 of these compounds, when added to water, best simulated the flavor of pufferfish, which involved strong umami (savory) and kokumi (mouthfulness) components. When the researchers added two flavor peptides they isolated in a prior study, the imitation pufferfish extract tasted even more like the real thing.

Older patients with a diagnosis of chronic sinusitis -- a disease of the nasal cavity and paranasal sinuses that often persists over many years -- have a unique inflammatory signature that may render them less responsive to steroid treatment, according to a new study published by Vanderbilt researchers.

The study published in the Journal of Allergy and Clinical Immunology examined tissue and mucus specimens of 147 patients between the ages of 18 to 78 who required sinus surgery for their chronic sinusitis.

With an initial goal of identifying subgroups of patients based on their inflammatory signature -- the different cytokines and inflammatory proteins found in tissue or mucus -- Vanderbilt investigators recognized that one of the identified subgroups was enriched in patients over age 60.

Intrigued by the findings, the team compared all patients according to age by examining their histopathology, tissue specimens taken during surgery, and the immune markers and inflammatory proteins found in their tissue and mucus, and noticed they were strikingly different.

"Most chronic sinusitis in North America -- particularly the kind that requires surgical intervention -- has an inflammatory signature characterized by a group of cytokines associated with allergy and asthma called Th2-associated cytokines," said Justin Turner, MD, PhD, associate professor of Otolaryngology-Head and Neck Surgery and a lead investigator for the study. "Older patients tend to not have significant elevations of those particular cytokines. In contrast, they have an elevation of cytokines that are associated with the body's innate immune function and both acute and chronic inflammatory responses, and that is highly dependent on age.

"You don't see an elevation in those cytokines until around age 60, and then from that age on, there's a progressive increase in the levels of those cytokines seen in the mucus and the tissue of those patients."

Because of this variation, older patients would theoretically be less likely to respond to the steroids used to treat chronic sinusitis characterized by Th2-associated cytokines.

According to Turner, topical steroids such as nasal sprays and irrigations are heavily relied upon for long-term disease and symptom management.

"We're hoping this data will stimulate some interest in the elderly population with respect to chronic sinusitis management, because it suggests we may need patient-specific treatments targeting these older patients. That's particularly important because steroids can have a number of short- and long-term adverse effects, and those side effects are much more likely in older patients than they are in younger patients," said Turner.

To solidify and build upon these findings, Turner's team is currently using data gathered over the last several years to compare surgical outcomes based on age.

Preliminary data suggest that older patients have less perceived benefit from sinus surgery than younger patients, which may be indicative that their disease is distinct and their options for post-operative medical management may be less likely to provide relief.

"Our end goal is that we're looking for better ways to treat chronic sinus disease and to understand the disease process a little better," said Turner. "We feel we have identified a characteristic of a fairly large population of patients that may ultimately change our treatment of those patients going forward. It at least suggests that we need to be doing more research targeted at that population."

Engineers at the University of Maryland (UMD) have created the first 3D-printed fluid circuit element so tiny that 10 could rest on the width of a human hair. The diode ensures fluids move in only a single direction--a critical feature for products like implantable devices that release therapies directly into the body.

The microfluidic diode also represents the first use of a 3D nanoprinting strategy that breaks through previous cost and complexity barriers hindering advancements in areas from personalized medicine to drug delivery.

"Just as shrinking electric circuits revolutionized the field of electronics, the ability to dramatically reduce the size of 3D printed microfluidic circuitry sets the stage for a new era in fields like pharmaceutical screening, medical diagnostics, and microrobotics," said Ryan Sochol, an assistant professor in mechanical engineering and bioengineering at UMD's A. James Clark School of Engineering.

Sochol, along with graduate students Andrew Lamont and Abdullah Alsharhan, outlined their new strategy in a paper published today in the open-access journal Scientific Reports.

Scientists have in recent years tapped into the emerging technology of 3D nanoprinting to build medical devices and create "organ-on-a-chip" systems. But the complexity of pushing pharmaceuticals, nutrients, and other fluids into such small environments without leakage--and the costs of overcoming those complexities--made the technology impractical for most applications requiring precise fluid control.

Instead, researchers were limited to additive manufacturing technologies that print features significantly larger than the new UMD fluid diode.

"This really put a limit on how small your device could be," said Lamont, a bioengineering student who developed the approach and led the tests as part of his doctoral research. "After all, the microfluidic circuitry in your microrobot can't be larger than the robot itself."

What sets the Clark School team's strategy apart is its use of a process known as sol-gel, which allowed them to anchor their diode to the walls of a microscale channel printed with a common polymer. The diode's minute architecture was then printed directly inside of the channel--layer-by-layer, from the top of the channel down.

The result is a fully sealed, 3D microfluidic diode created at a fraction of the cost and in less time than previous approaches.

The strong seal they achieved, which will protect the circuit from contamination and ensure any fluid pushed through the diode isn't released at the wrong time or place, was further strengthened by a reshaping of the microchannel walls.

"Where previous methods required researchers to sacrifice time and cost to build similar components, our approach allows us to essentially have our cake and eat it too," Sochol said. "Now, researchers can 3D nanoprint complex fluidic systems faster, cheaper, and with less labor than ever before."

SAN ANTONIO -- Jan. 23, 2019 -- A new Southwest Research Institute study tackles one of the greatest mysteries about Titan, one of Saturn's moons: the origin of its thick, nitrogen-rich atmosphere. The study posits that one key to Titan's mysterious atmosphere is the "cooking" of organic material in the moon's interior.

"Titan is a very interesting moon because it has this very thick atmosphere, which makes it unique among moons in our solar system," said Dr. Kelly Miller, research scientist in SwRI's Space Science and Engineering Division and lead author of the study. "It is also the only body in the solar system, other than Earth, that has large quantities of liquid on the surface. Titan, however, has liquid hydrocarbons instead of water. A lot of organic chemistry is no doubt happening on Titan, so it's an undeniable source of curiosity."

The atmosphere of Saturn's largest moon is extremely dense, even thicker than Earth's atmosphere, and is comprised mainly of nitrogen gas.

"Because Titan is the only moon in our solar system with a substantial atmosphere, scientists have wondered for a long time what its source was," she said. "The main theory has been that ammonia ice from comets was converted, by impacts or photochemistry, into nitrogen to form Titan's atmosphere. While that may still be an important process, it neglects the effects of what we now know is a very substantial portion of comets: complex organic material."

Another odd aspect of Titan's atmosphere is that it's also about 5 percent methane, which reacts quickly (by astrophysical standards) to form organics that gradually fall to the surface. As a result, the atmospheric methane would either have to be replenished somehow or this current period of time is simply a unique era for Titan.

Miller's investigation was spurred by data from the Rosetta spacecraft, a European Space Agency probe that studied the distant comet 67P/Churyumov-Gerasimenko with NASA participation and delivered the surprising discovery that the comet was roughly half ice, a quarter rock and a quarter organic material.

"Comets and primitive bodies in the outer solar system are really interesting because they're thought to be leftover building blocks of the solar system," she said. "Those small bodies could be incorporated into larger bodies, like Titan, and the dense, organic-rich rocky material could be found in its core."

To study the Titan mystery, Miller combined existing data from organic material found in meteorites with previous thermal models of the moon's interior to see how much gaseous material could be produced and whether it was comparable to the atmosphere now. Following the standard rule of, "If you cook something, it will produce gases," Miller found that approximately half of the nitrogen atmosphere, and potentially all of the methane, could result from the "cooking" of these organics that were incorporated into Titan at its very beginning.

Some people use fidget spinners -- flat, multi-lobed toys with a ball bearing at the center -- to diffuse nervous energy or whirl away stress. Now, researchers have found a surprising use for the toys: separating blood plasma for diagnostic tests. The new approach, reported in ACS' journal Analytical Chemistry, could be useful for medical applications in regions of the world that lack electricity and other resources. Watch a video of the spinner in action here.

Before doctors can perform many types of blood tests, they must separate blood cells from plasma, the yellowish fluid that contains proteins, bacteria, viruses, metabolites and other substances that can be used to diagnose disease. This is most often accomplished by centrifugation, which uses high-speed rotation to sediment blood cells. However, centrifuges are expensive and require electricity that might not be available in resource-limited regions. Chien-Fu Chen, Chien-Cheng Chang and colleagues wondered if a commercially available fidget-spinner could generate enough force to separate blood plasma with the flick of a finger.

To find out, the researchers placed human blood samples in tiny tubes, sealed the ends and taped a tube to each of the three prongs of a fidget-spinner. They found that by flicking the spinner with a finger three to five times, they could separate about 30 percent of the plasma with 99 percent purity in only four to seven minutes. To verify that the plasma was suitable for diagnostic tests, the researchers spiked blood with a human immunodeficiency virus-1 (HIV-1) protein, separated the plasma with the spinner and performed a paper-based detection test. The inexpensive, simple method detected clinically relevant concentrations of the viral protein in only a drop of blood.

The question of how quickly the universe is expanding has been bugging astronomers for almost a century. Different studies keep coming up with different answers -- which has some researchers wondering if they've overlooked a key mechanism in the machinery that drives the cosmos.

Now, by pioneering a new way to measure how quickly the cosmos is expanding, a team led by UCLA astronomers has taken a step toward resolving the debate. The group's research is published today in Monthly Notices of the Royal Astronomical Society.

At the heart of the dispute is the Hubble constant, a number that relates distances to the redshifts of galaxies -- the amount that light is stretched as it travels to Earth through the expanding universe. Estimates for the Hubble constant range from about 67 to 73 kilometers per second per megaparsec, meaning that two points in space 1 megaparsec apart (the equivalent of 3.26 million light-years) are racing away from each other at a speed between 67 and 73 kilometers per second.

"The Hubble constant anchors the physical scale of the universe," said Simon Birrer, a UCLA postdoctoral scholar and lead author of the study. Without a precise value for the Hubble constant, astronomers can't accurately determine the sizes of remote galaxies, the age of the universe or the expansion history of the cosmos.

Most methods for deriving the Hubble constant have two ingredients: a distance to some source of light and that light source's redshift. Looking for a light source that had not been used in other scientists' calculations, Birrer and colleagues turned to quasars, fountains of radiation that are powered by gargantuan black holes. And for their research, the scientists chose one specific subset of quasars -- those whose light has been bent by the gravity of an intervening galaxy, which produces two side-by-side images of the quasar on the sky.

Light from the two images takes different routes to Earth. When the quasar's brightness fluctuates, the two images flicker one after another, rather than at the same time. The delay in time between those two flickers, along with information about the meddling galaxy's gravitational field, can be used to trace the light's journey and deduce the distances from Earth to both the quasar and the foreground galaxy. Knowing the redshifts of the quasar and galaxy enabled the scientists to estimate how quickly the universe is expanding.

The UCLA team, as part of the international H0liCOW collaboration, had previously applied the technique to study quadruply imaged quasars, in which four images of a quasar appear around a foreground galaxy. But quadruple images are not nearly as common -- double-image quasars are thought to be about five times as abundant as the quadruple ones.

To demonstrate the technique, the UCLA-led team studied a doubly imaged quasar known as SDSS J1206+4332; they relied on data from the Hubble Space Telescope, the Gemini and W.M. Keck observatories, and from the Cosmological Monitoring of Gravitational Lenses, or COSMOGRAIL, network -- a program managed by Switzerland's Ecole Polytechnique Federale de Lausanne that is aimed at determining the Hubble constant.

Tommaso Treu, a UCLA professor of physics and astronomy and the paper's senior author, said the researchers took images of the quasar every day for several years to precisely measure the time delay between the images. Then, to get the best estimate possible of the Hubble constant, they combined the data gathered on that quasar with data that had previously been gathered by their H0liCOW collaboration on three quadruply imaged quasars.

"The beauty of this measurement is that it's highly complementary to and independent of others," Treu said.

The UCLA-led team came up with an estimate for the Hubble constant of about 72.5 kilometers per second per megaparsec, a figure in line with what other scientists had determined in research that used distances to supernovas -- exploding stars in remote galaxies -- as the key measurement. However, both estimates are about 8 percent higher than one that relies on a faint glow from all over the sky called the cosmic microwave background, a relic from 380,000 years after the Big Bang, when light traveled freely through space for the first time.

"If there is an actual difference between those values, it means the universe is a little more complicated," Treu said.

On the other hand, Treu said, it could also be that one measurement -- or all three -- are wrong.

The researchers are now looking for more quasars to improve the precision of their Hubble constant measurement. Treu said one of the most important lessons of the new paper is that doubly imaged quasars give scientists many more useful light sources for their Hubble constant calculations. For now, though, the UCLA-led team is focusing its research on 40 quadruply imaged quasars, because of their potential to provide even more useful information than doubly imaged ones.

In the animal kingdom, food access is among the biggest drivers of habitat preference. It influences, among other things, how animals interact, where they roam and the amount of energy they expend to maintain their access to food. But how do different members of ecologically similar species manage to live close to each other?

This question was on the mind of UC Santa Barbara postdoctoral scholar Jacob Eurich as he studied territorial damselfish in Kimbe Bay, Papua New Guinea. Located within the Coral Triangle of the Indo-Pacific region, which is recognized for the greatest richness of marine life in the world, the coral reefs in the area are home to a variety of damselfish. This includes seven species that inhabit their own particular spaces, in some cases within mere meters of one another.

"Previously, scientists thought that all territorial damselfishes were herbivorous, farm algae and basically do the same thing ecologically on reefs," explained Eurich, who conducted this research while at James Cook University in Australia. "Damselfish" is a very broad category, he added, with members such as clownfishes and the Californian garibaldi in the same family. The species of damselfish that are the subject of this research are the tropical territorial types, known to cultivate and protect algal beds on coral reefs.

In research published in the science journal Marine Biology, Eurich sought to understand how neighboring communities of these fish -- which live in an ecological community of intense competition for resources -- manage to thrive.

"We set out to understand how they live so close to one another without directly competing, and why," he said.

The answer came after an in-depth look at the fishes' diets using stable isotope analysis, which detects certain types of elements in their muscle tissues and links them to potential food items.

"It is based on the principle, 'you are what you eat,'" Eurich explained. Rather than getting a snapshot of an animal's diet by looking at its stomach contents, stable isotope analysis provides a long-term picture of what the animal consumes on a regular basis because the food is incorporated into the animal's tissue.

The result? These farming fish are not exclusively farmers, nor are they exclusively vegetarian.

"The analysis proved that in fact not all territorial damselfish are herbivorous and we found evidence of planktivory, quite the opposite feeding regime," Eurich said. Further, he added, these species had previously only been known to eat things off the reef. "We found evidence of two species foraging for food that drift by in the water column."

These findings are significant on several levels. They indicate that certain broad ecological categorizations -- such as the classification of territorial damselfish as herbivores -- may not adequately serve some species, or the scientists and conservationists that study them.

"I think it is a cautionary flag to scientists in all ecological-related fields to be careful when generalizing groups of similar species," Eurich said. "Each species is likely partitioning a resource and if it doesn't look like they are, there is a chance a technology with a finer resolution is needed to detect differences."

Also, the study demonstrates an example of adaptation in areas of high competition for resources.

"An animal can't spend all of their time and energy fighting a neighbor," Eurich said. "In this study we showed some of the species switched diets to reduce competition."

As climate change and subsequent ocean acidification and coral bleaching continue to affect life on the reef, territorial damselfish will remain one species to watch as they adapt to shifting conditions. So far they seem to be successful, in fact they are regarded "winners" of coral bleaching.

"Where most species die off due to the coral habitat loss, these algae-farmers actually increase in abundance," said Eurich, who is now based in the McCauley Lab at UC Santa Barbara's Marine Science Institute. "The study here shows how many of these species may coexist in the future. I think it is important to look at the competition and coexistence of species that may be the most abundant on future reefs."

CHAMPAIGN, Ill. -- Growing muscle tissue on grooved platforms helps neurons more effectively integrate with the muscle, a requirement for engineering muscle in the lab that responds and functions like muscle in the body, University of Illinois researchers found in a new study.

Such engineered muscle with integrated nerves has applications in reconstructive and rehabilitative medicine, as well as for engineered biological machines or robots.

"With this approach, we can engineer muscle outside of the body so it can respond like muscle in the body," said study leader Hyunjoon Kong, a professor of chemical and biomolecular engineering. "Usually people just culture muscle cells without neurons. It's quite straightforward to do that. But it's very difficult for neurons to integrate and communicate with the muscle so that it's functional and responsive."

Kong co-led the study with Rashid Bashir, a professor of bioengineering and dean of the College of Engineering. Bashir and Kong also are affiliated with the Carle Illinois College of Medicine.

The researchers' goal is to create muscle that responds to neurotransmitters as it responds in the body, rather than relying on added electrical or chemical stimulation. While other groups have demonstrated engineered muscle with some nerve integration, called innervation, the function and response of the muscle has been limited, the researchers say.

The Illinois group altered the surface on which they incubated the muscle to see if topology affected muscle growth, function or innervation. The researchers grew mouse muscle tissue on increasingly grooved surfaces, then seeded the muscle with stem cells primed to become neurons and watched how the nerves formed and integrated with the muscle.

They found that on a flat surface, the muscle tissue lacked organization and nerves did not penetrate efficiently. However, the more grooved the surface, the more ordered the muscle fibers grew and the more successfully the neurons integrated with the muscle, said graduate student Clare (Eunkyung) Ko, the first author of the study.

"If you think about the physiological properties of muscle, it's very aligned. There are a lot of fibers bundled together. The grooved substrate provides a similar environment to our natural skeletal muscle, so it can help the cells to align and form bundles like a real muscle," Ko said. "These aligned bundles also guide the neurons as they extend along and into the muscle tissue. It gives them a path to grow."

The researchers then tested the innervated muscle's response to two neurotransmitters, natural chemicals that signal nerve cells - one that stimulates activity and one that inhibits it. The tissues grown on the grooved surfaces were the most responsive.

"If the muscle and neurons are functioning together, the muscles should contract when exposed to the chemical that stimulates neurons, and stop when exposed to the inhibitors. Ours did that," Kong said. "We are the first ones to demonstrate that our muscle is functional and responding to these chemicals much better than others."

The researchers plan to refine their grooved substrates in experiments with human muscle and nerve cells. They hope to develop their approach as a platform for drug screening and for tissue engineering for patients with muscle damage or injury.

"When there is damage to the muscle, there often is a gap in the nerves as well. This can cause the muscle to become weaker and smaller. So for injury treatment, it's important to let the neurons re-innervate the muscle," Kong said. "We could use a patient's own cells to engineer muscle samples to screen which drugs could enhance the reintroduction of neurons to the muscle. We could test a variety of growth factors or proteins and see which would be good for regeneration of the muscle with the neurons together."

The researchers also plan to use the innervated muscle to power miniature biological machines, or bio-bots. Bashir's group has developed bio-bots powered by muscle tissue that responds to electricity and light, and integration with neurons would provide the machines with sensing capability that could provide direction - for example, moving toward an environmental toxin to neutralize it, Bashir said.

"Our goal is to build a little neuronal circuit that could sense chemical concentration and translate that to motion," Bashir said.

PULLMAN, Wash.--Erik Johnson has what looks like a surefire way to hurt support for spending to protect the environment: Elect a Democratic president.

Johnson, a Washington State University sociologist, teased apart the opinions of more than 20,000 people over more than four decades and saw that support for environmental spending consistently plummeted during the administrations of Jimmy Carter, Bill Clinton and Barack Obama, Democrats all.

Johnson made his discovery using a statistical analysis that looked at poll respondents in terms of their age, the time period in which they were surveyed and the cohort of similarly aged people. Support for environmental spending consistently declines as people get older and one's cohort has only a modest effect on his or her environmental views. But one's relative support for the environment changes dramatically depending on which party is in the White House.

Indeed, the current Republican-Democrat divide over the environment is about the same as it was at the end of the Carter administration in 1980, Johnson said.

"What's driving the divide is really these presidential politics," he said.

Johnson and Philip Schwadel, a professor of sociology at the University of Nebraska-Lincoln, publish their findings this week in the journal Social Forces. Their study used data from the General Social Survey between 1973 and 2014, covering what the authors call "the longest time span of any available set of frequently measured trend data on environmental concerns."

Historically, Republicans have been pro-environment. Abraham Lincoln set aside California's Yosemite Valley for "public use, resort, and recreation," setting the stage for the National Park System. Teddy Roosevelt was "the conservation president." Richard Nixon created the Environmental Protection Agency.

Overall environmental support was once so consistent that the editor of Public Opinion Quarterly in 1972 called it "a miracle of public opinion." But that support slipped by the end of the decade, Johnson and Schwadel write, "when President Carter was being mocked by conservatives for suggesting that Americans try donning a sweater before turning up the heat in their houses."

The election of Ronald Reagan, a Republican, "marked a key turning point in the politicization of environmental issues," Johnson and Schwadel write, as Reagan ran on a platform that included changes in federal land control and rolling back antipollution legislation. Yet support for environmental spending bounced back under his two terms and the subsequent term of George H. W. Bush, another Republican.

Johnson said the swings in opinion come largely from Republicans. Democratic support for the environment is consistently high, while Republicans tend to be mobilized when a Democrat moves into the oval office.

"They get concerned about overreach an environmental policy," Johnson said. "They know that the government is going to be proactive on environmental policy so they're less supportive of it. They are usually opposed to a lot of Democratic presidential policies."

When a Republican is president, he said, Republican voters will actually come to look pretty much like Democrats and Independents in their environmental support. The first Bush presidency took several pro-environment steps, including the U.S. Global Change Research Program and the ozone-layer protections of the 1990 Clean Air Act. Republican voters took the measures in stride.

The outsize role of the presidency in environmental opinion is a testament to the office, said Johnson and Schwadel.

"Presidents are leaders of their political parties and important drivers of news cycles," they write. "They also sit atop a large federal bureaucracy with considerable discretion over federal environmental policy, building a record of governance that political opponents may hold up for criticism, and to which partisans in the minority are particularly likely to be cued."

The airborne transmission of diseases including the common cold, influenza and tuberculosis is something that affects everyone with an average sneeze or cough sending around 100,000 contagious germs into the air at speeds of up to 100 miles per hour.

New research led by scientists from the University of Bristol and published today in the Journal of the Royal Society Interface, outlines a new technique that, for the first time, examines directly the environmental factors that control the transmission of disease to the level of a single aerosol particle and a single bacterium.

Aerosol droplets are a typical route for the transport of pathogens, such as bacteria and viruses, and the airborne transmission of disease.

The impact of environmental factors (such as relative humidity, temperature, atmospheric oxidants and the presence of light) on the viability and infectivity of pathogens in aerosol droplets remains poorly understood.

For example, although the seasonal variation in influenza cases is known, the environmental factors determining the differences in airborne transmission of the virus is not well understood.

To help understand this process better, scientists have established a novel approach for forming aerosol droplets containing a specific number of bacteria, trapping a cloud of these droplets of exact known population and simulating their environmental exposure over a time from five seconds to several days.

The aerosol droplets are then gently sampled onto a surface to determine how many bacteria have survived their time in the aerosol phase.

The study reports on the benchmarking of this new approach, demonstrating the many advantages over conventional techniques, which include introducing large populations of droplets to large rotating drums or capturing droplets on spiders' webs.

Not only can measurements be made down to the single bacterium/single droplet level requiring very little quantity of aerosol (picolitres), but high time resolution (one second) measurements of viability can be made, allowing the first quantitative studies of the influence of dynamic factors transforming the aerosol (for example evaporation, condensation) on viability.

For example, the study shows that during evaporation of droplets, the concentration of typical salts can rise way beyond their solubility limit, placing considerable osmotic stress on the bacteria and reducing viability.

Lead author, Professor Jonathan Reid from the University of Bristol's School of Chemistry, said: "This new technique offers the eventual prospect of allowing refined measurements to improve our understanding of the transmission of many airborne diseases including tuberculosis, the influenza virus, and foot and mouth disease."

A new study using Pop-Up health check stations found a possible link between 'unhealthy' shopping centres and the number of cases of suspected or diagnosed high blood pressure recorded for people who volunteered for checks.

Researchers from City, University of London set up the one day Pop-Up health check stations in seven shopping centres across England, and invited passers-by to have a test to screen for signs of the eye disease, glaucoma. The testing was led by optometrist, Laura Edwards, from the University.

Blood pressure readings were also offered 50 per cent of the time to attract potential volunteers with a more comprehensive and familiar health screening.

It is well known that persistent high blood pressure (hypertension) can increase your risk of a number of serious and potentially life-threatening conditions including heart attack, and stroke.

The research team classed retail outlets in shopping centres as 'unhealthy' if they were either a fast-food takeaway, a bookmaker, a tanning salon or a payday loan business, in line with a Royal Society of Public Health (RSPH) report ranking UK town and city shopping centres based on their 'unhealthy' and 'healthy' retail outlets.

The researchers also produced a basic score of each shopping centre's 'unhealthiness', which was the proportion of 'unhealthy' retail outlets open on the day of testing relative to the total number of retail outlets open in the shopping centre.

The Pop-Up health check stations were set up in four shopping centres from the top 10 'unhealthiest' shopping centres from the RSPH ranking, and three from the top 15 'healthiest' shopping centres in the ranking.

On analysis, the researchers found a link between the number of adult volunteers recorded as having suspected or diagnosed high blood pressure (repeat blood pressure readings at or above 140/90 mmHg) and the 'unhealthiness' score they had developed for each shopping centre, which was a statistically significant result.

They also found that in the three 'healthy' shopping centres sampled from the RSPH report ranking (Bristol, Cambridge and Nottingham), 20 out of 152 adults (13.1%) were flagged as having readings of high blood pressure on repeat testing.

In the four 'unhealthy' shopping centres sampled (Coventry, Preston, Northampton, Stoke-on-Trent), 45 out of 199 adults (22.6%) had readings of high blood pressure.

The difference in the proportion of readings of high blood pressure in 'healthy' versus 'unhealthy' shopping centres was also a statistically significant result, translating into a 72 per cent increased likelihood of suspected or diagnosed high blood pressure being reported in an 'unhealthy' shopping centre relative to a 'healthy' shopping centre.

The study has its limitations, including Pop-Up health check station assessments not being able to offer a definitive diagnosis of high blood pressure. Based on an RSPH report, the 'unhealthiness' score of retail outlets in shopping centres used is a surrogate marker of the 'healthiness' of the shopping area, and has not been validated in other studies.

The findings may point to strategies for targeted outreach testing and screening of blood pressure in shopping centres that could be the subject of further investigation, potentially in the context of reducing health inequalities.

The study is published in the journal BMC Public Health.

David Crabb, Professor of Statistics and Vision Research at City, University of London and who led the research team, said:

"Less than half of those adults aged 40-74 offered the free NHS health check take it. The British Heart Foundation also recently called for NHS health staff to take blood pressure checks at gyms, barbershops and football stadiums and offer blood pressure checks in the workplace. We know that more, effective ways of screening people for high blood pressure are needed, and this study offers an insight into some ways that may be done.

"In our study, over half those recorded as having high blood pressure were aware of having the condition or reported a history of high blood pressure. It may be that differences between 'unhealthy' and 'healthy' shopping centres could be attributed to differences in detection of high blood pressure, management of high blood pressure or a combination of the two. Both have substantial public health importance, and their relationship to socioeconomic status should be studied further."

Shirley Cramer CBE, Chief Executive of the Royal Society for Public Health, said:

"Our research into UK high streets illustrated how unhealthy businesses concentrate in areas already experiencing lower life expectancy, and this valuable new research explores in detail one of the many factors at play within this alarming trend. The least healthy shopping centres visited by the Pop-Up health check stations are all within some of the most socially deprived areas of the country, so the results of this study exemplify the stark health inequalities that are entrenched across the UK. Exposing and dismantling those health inequalities is a public health priority, and we welcome all promising opportunities for doing so."

New research published in The Journal of Physiology indicates shift work exposure in mothers can result in reduced fetal growth and longer pregnancies, even when the shift work is only carried out early in pregnancy.

Shift work interferes with normal patterns of sleep activity, eating times and exposure to light. Shift workers are at increased risk of developing type 2 diabetes and obesity, but effects on metabolism have not been studied in human pregnancy. While shift work has been associated with impaired pregnancy outcomes, until now the mechanisms have not been understood. Importantly, it was not known when women should stop shift work to prevent adverse effects on their pregnancies. Researchers found that shift work could impair glucose tolerance of mothers in early pregnancy, which means mothers had poorer control of their blood glucose levels. They demonstrated that shift work during pregnancy can disrupt maternal circadian rhythms, or the 24-hour body clock, and metabolism. These findings could inform public policy and workplace practices for shift work during pregnancy in women.

Previous studies have shown that disrupted sleep patterns in rodents can affect pregnancy outcomes. This study considers effects in sheep as they provide an excellent animal model for human pregnancy. The study, conducted by the University of Adelaide and South Australian Health and Medical Research Institute, involved simulating shift patterns in groups of sheep, with either light on during the day and food provided each morning, or the timing of light and feeding changed to mimic a rotation between day and night shift during each week. The researchers measured maternal circadian rhythms and glucose control in early and late pregnancy, and weighed all lambs at birth.

Exposure to a model of rotating shift work impaired glucose tolerance in sheep during early pregnancy, just as it does in non-pregnant human adults. Reduced fetal growth was seen in pregnancies with a single foetus and longer pregnancies in mothers carrying twins. Importantly, this was the case even when mothers stopped simulated shift work after the first third of pregnancy. This suggests that exposure to rotating night and day shifts, even if only in early pregnancy, may adversely affect maternal metabolic and pregnancy outcomes.

The researchers now hope to identify shift work patterns that do not adversely affect the mother's metabolism or pregnancy outcomes. The limitation of this research is that most human pregnancies are singletons, but in this study there were a similar number of twins and singletons, due to the peak fertility of sheep around equinox when they were mated. This reduced the researcher's ability to compare effects of different durations of shift work on pregnancy outcomes.

Dr Kathy Gatford, leading author on the study, commented on the findings:

'The effects of shift work on pregnancy are not well understood. We found that exposure to rotating night and day shifts, even if only early in pregnancy, altered both maternal metabolic and pregnancy outcomes. We are now assessing whether maternal shift work affects the health of their children by looking at circadian rhythms, cardiometabolic health and body composition in the progeny in this study.'

Philadelphia, January 22, 2019 - Nearly a quarter of employed adults obtain foods and beverages at work at least once a week, according to a new study from the US Centers for Disease Control and Prevention (CDC) and published in the Journal of the Academy of Nutrition and Dietetics. Foods obtained at work are often high in calories, refined grains, added sugars, and sodium.

Using data collected in 2012-13 from the large, nationally representative Food Acquisition and Purchasing Survey (FoodAPS), CDC investigators found that 23.4 percent of the 5,222 study participants obtained food at least once a week at work. The average weekly calories obtained was 1,292, and in general the foods consumed at work did not align well with the Dietary Guidelines for Americans.

"Employers can offer appealing and healthy options in cafeterias, vending machines, and at meetings and social events," said lead CDC investigator Stephen J. Onufrak, PhD, a researcher with CDC's Division of Nutrition, Physical Activity, and Obesity, Atlanta, GA, USA. "One way to do this is by incorporating food service guidelines and healthy meeting policies into worksite wellness efforts."

Improving the nutritional quality of foods consumed at work can be a key component in worksite wellness efforts. Obesity and low dietary quality are important risk factors for chronic diseases such as heart disease, type 2 diabetes, and cancer. These conditions represent seven of the top 10 leading causes of death in the US and treating them accounts for 84 percent of healthcare costs. In 2010, nearly three in 10 employed adults had obesity. Employed adults with obesity reported lower consumption of fruits and vegetables and less frequent leisure time physical activity than normal weight adults.

With about 150 million working adults in the US, worksite wellness efforts to prevent chronic disease can reach a large portion of the American public. These programs have been shown to be effective at changing health behaviors among employees, reducing employee absenteeism, and reducing healthcare costs.

"Incorporating food service guidelines into wellness programs can help employers offer appealing and healthy options that give employees a choice," suggested Dr. Onufrak.

The foods analyzed in the study were either purchased from worksite vending machines or cafeterias, or obtained for free in common areas, during meetings, or at worksite social events. The study did not include foods that people brought into work from home for their own consumption or foods obtained at an off-site restaurant or retail outlet during work hours.