Tech

Riyadh, Saudi Arabia 7 March 2019: Waterpipe and cigarette smoking are associated with heart attacks at a younger age in Saudi Arabians, reports a study presented at the 30th Annual Conference of the Saudi Heart Association (SHA 30). Smokers have more complications and worse outcomes.

SHA 30 takes place from 7 to 9 March in Riyadh. Joint scientific sessions are being held by the European Society of Cardiology (ESC) and SHA as part of the ESC Global Activities programme.1

Study author Dr Farhan A.W. Khan, of King Abdullah Medical City, Mecca, Saudi Arabia, said: "In addition to cigarette smoking, water pipe smoking - also called hookah and shisha - is very common in the Middle East due to social trends and the misconception that it is less harmful than cigarettes. More than one in ten Saudi Arabians smoke, starting at an average age of 19, while 9% of smokers start before age 15."2

All types of smoked tobacco, including water pipe, increase the risk of cardiovascular disease.3 This study examined levels of cigarette and waterpipe smoking and outcomes in 1,554 heart attack patients presenting to King Abdullah Medical City between 2015 and 2018.

The average age at the time of heart attack was 54 years for smokers and 60 years for non-smokers - a statistically significant difference - despite diabetes mellitus and hypertension being less frequent in smokers. Smokers were more likely to have multiple arteries affected and more likely to have bigger, severe heart attacks in the form of ST-elevation myocardial infarction. Complications of heart attack, including pulmonary oedema and cardiac arrest, were more common in smokers. Smokers had a trend towards higher in-hospital mortality (4.0% versus 2.4%). More than one-third (38%) of heart attack patients were current smokers.

Smokers were predominantly men (98%). Regarding ethnicity, 50% of Arab patients and 35% of South Asian heart attack patients were smokers. More than half (51%) of patients living in Mecca were smokers, while 30% of patients on pilgrimage were smokers.

Dr Khan said: "Like studies from Western countries, our data suggest that smokers have heart attacks at a significantly younger age than non-smokers. Moreover, smokers have heart attacks even without other risk factors including diabetes and hypertension, and they have poorer outcomes."

He continued: "There is limited awareness in the Middle East about the harmful effects of smoking, and particularly about the health risks of water pipe smoking. Tobacco products are reasonably cheap compared to the average income in Saudi Arabia. Young people in Saudi Arabia are particularly at risk of starting and continuing to smoke and there is also a growing trend in young females."

The Saudi Ministry of Health started a national tobacco control programme in 2002 and smoking is banned in most public places.2 Tobacco packages must have health warnings and selling tobacco products to minors is prohibited. Dr Khan said more efforts are needed to enforce smoking bans and there should be higher taxes on tobacco products. Doctors and nurses should ask about smoking at each encounter, give advice to help smokers kick the habit, and refer smokers to dedicated cessation programmes. After a heart attack, smokers should be referred to cardiac rehabilitation programmes with smoking cessation services.

Dr Khan said: "Campaigns are needed to raise awareness about the harmful effects of waterpipe and cigarette smoking, particularly in young people so that they never take up the habit. People of all ages can improve their health and reduce their risk of heart problems if they quit smoking."

Dr Fayez Bokhari, head of the Scientific Committee of SHA 30, said: "Saudi Arabia has made great progress in tobacco prevention including a ban on all forms of smoking advertising, a ban on smoking in public places and new added taxes on tobacco products; this is in addition to active educational campaigns. Despite all these efforts, smoking is still a major health problem with a huge burden to the economy. Data from The Ministry of Health of Saudi Arabia indicates that smoking kills 71 men and 21 women every week in Saudi Arabia along with 4,545 million Saudi Riyals in tobacco related-costs to the government."4

Professor Marco Roffi, course director of the ESC programme at SHA 30, said: "Smoking can be lethal not only because of heart attacks but also stroke and cancer. Smoking is particularly dangerous in association with diabetes, a condition with high prevalence in the Middle East. The ESC prevention guidelines recommend no exposure to tobacco in any form.3 People who stop smoking generally halve their risk of cardiovascular disease. ESC advice to reduce smoking includes higher taxes and prices on all tobacco products, banning smoking in public places, and prohibiting sales of tobacco products to adolescents."

Translocation is an important management tool that has been used for more than 50 years to increase bighorn sheep population numbers in Arizona and to restore herds to suitable habitat throughout their historical range. Yet, translocation also can alter the underlying genetic diversity and spatial structure of managed wildlife species in both beneficial and detrimental ways.

A University of Wyoming researcher led a seven-year study to evaluate the long-term impact of translocation actions on bighorn sheep. From 2005-2012, the research group characterized statewide genetic structure and diversity by using microsatellite and mitochondrial DNA data in 16 indigenous and translocated bighorn sheep populations in Arizona.

"Our study showed that it is possible to re-establish bighorn sheep populations without a reduction of gene diversity over a short period and without erosion of ancestral lineage," says Holly Ernest, a UW professor of wildlife genomics and disease ecology, and the Wyoming Excellence Chair in Disease Ecology in the Department of Veterinary Sciences and the Program in Ecology.

Ernest was the senior and corresponding author of a paper, titled "Genetic Outcomes of Translocation of Bighorn Sheep in Arizona," that was published today (March 6) in the Journal of Wildlife Management. The journal publishes manuscripts containing information from original research that contributes to basic wildlife science. Suitable topics include investigations into the biology and ecology of wildlife and their habitats that have direct or indirect implications for wildlife management and conservation.

Daphne Gille, a postdoctoral researcher at the University of California-Davis, was the paper's lead author. Ernest was Gille's Ph.D. mentor on this project while Ernest was a professor at UC-Davis until 2014 and, together, they continued the work after Ernest moved to UW.

Additionally, researchers from the Oregon State University, California Department of Fish and Wildlife, Arizona Game and Fish Department, Nevada Department of Wildlife, the National Park Service and the Center for Large Landscape Conservation contributed to the research and the paper.

Translocation is a tool used in wildlife management that involves the intentional, human-mediated movement of individual animals, populations or species from one area with release in another. Translocation of bighorn sheep in Arizona began in 1958, initially to augment numbers and maintain genetic integrity among populations of the two desert bighorn sheep lineages: Nelson and Mexican. Later, translocation management included augmentation of Rocky Mountain bighorn sheep that emigrated from New Mexico.

Translocations have been used to achieve a number of management and conservation goals, including to increase population abundance of threatened species; to restore species to their historical range; to preserve biodiversity; to mitigate the effects of climate change; and to enhance genetic diversity and prevent inbreeding depression.

Populations that were recipients of translocated animals showed substantial genetic diversity, according to the paper. This was contrary to previous studies that described "genetic bottlenecks," or low genetic diversity, as a result of translocation in certain populations, Ernest says.

"In Arizona, we found there was quite a bit of diversity in these translocated populations, and that was a good thing," Ernest says.

She adds that the Arizona Game and Fish Department and other wildlife management agencies use a method called "population supplementation" in which bighorn sheep are moved to an existing herd in another location.

"When useful to augment populations, wildlife agencies might translocate a few bighorn sheep in one year and, in another year, put a few more in," she says. "Also, translocation efforts can include reintroducing whole populations into empty, historic habitats that have been used by bighorn sheep in the past, or by supplementing the smaller, weak populations that need fresh genetics."

In northern Arizona, the presence of two indigenous main groups of Nelson bighorn sheep were confirmed in the Black Mountains and Grand Canyon, and indicated that gene flow among the Grand Canyon populations has likely played a role in maintaining genetic diversity.

In southern and west-central Arizona, researchers detected genetic structure consistent with two metapopulations of Mexican desert bighorn sheep.

Analyses of this study show significant genetic differences within each desert bighorn sheep lineage and, thus, suggest an important difference from current management practices that consider each lineage to be a single genetic unit. According to the study, several lines of genetic evidence presented suggest that the Bill Williams River area in Arizona is the contact zone for the two desert lineages of bighorn sheep. However, the degree to which translocation has enhanced introgression -- genetic mixture -- is unknown.

Despite relative isolation from other herds, the translocated Rocky Mountain bighorn sheep population in eastern Arizona had high levels of genetic diversity and no evidence of inbreeding. This is conceivable due to multiple translocation events from sources in Colorado and New Mexico.

"Evidence shows that, even with moving bighorn sheep around for conservation and management, it didn't affect these three precious lineages," Ernest says. "They maintained their differentiation in size and horn types. Hikers and biologists care about this. Hunters care about these differences."

While translocation management has successfully contributed to the re-establishment of bighorn sheep populations in Arizona without diminishing genetic diversity, the paper stresses that future translocation should proceed with caution to preserve the genetic integrity and potential location adaptation within the Nelson and Mexican desert metapopulations in the study.

Ecological farmlands help protecting bird populations and reducing the effects of global change on the environment, according to a study published in the journal Agriculture, Ecosystems and Environment by the experts Joan Real, Àlex Rollan and Antonio Hernández-Matías, from the Conservation Biology Group of the Faculty of Biology and the Biodiversity Research Institute of the University of Barcelona (IRBio).

According to the study, which counted on the support from Torres Family, from Vilafranca del Penedès (Spain), the ecological viticulture increases the abundance and amount of species of farmland birds, and favours the insectivore bird populations that help the natural control of plagues in ecological crops. This agricultural practise helps improving the resilience of farmland birds -which are especially sensitive to environmental changes- towards the effects of global warming.

Farmland birds: at risk due intensive agriculture and climate change

Changes in agricultural production systems -from traditional to intensive- generated several environmental impacts on the environment, such as the loss of biodiversity. At the moment, intensive agricultural exploitation in Europe caused the loss of millions of farmland birds, which are also affected by global change.

In this context, the practice of ecological viticulture has spread over the last years in the sector of the vineyards, one of the most traditional cultures in the country. In Catalonia, this sector represents the first important ecological crop in the agricultural field, and one of every four vineyards has its origins in ecological agricultural production. Without insecticides, herbicides or chemical fertilizers, this practice includes a series of ecological and integrated techniques (mechanical control of plagues, etc.) in a context of a growing social interest for sustainable practices with biodiversity and the environment.

What is the impact of ecological crops in farmland birds?

The beneficial effects of the ecological crops of vineyards on several organisms were known from years ago. "However -says Àlex Rollan, first author of the study-, there wasn't much information on their real impact in the community of farmland birds".

In this context, from 2014 to 2015, UB-IRBio experts created bird censuses in a total of thirty-three vineyard parcels -designation of Origin Penedès- to see how the practice of ecological agriculture affected the community of farmland birds -insectivore ones mostly- and the most vulnerable species to climate change.

The new study describes for the first time the positive impact of the ecological viticulture on the abundance and amount of species of insectivore birds in the Mediterranean vineyards. The presence of herbaceous cover -a growing practice in European vineyards- has a beneficial effect on insectivore birds, in particular in spring and other seasons when people work on ecological crops, according to the study carried out by the Conservation Biology Group (UB-IRBio).

A more environment-friendly agricultural production

Birds are sensitive to changes and impacts that occur in the ecosystems worldwide. "Therefore, they are perfect bioindicators, since they show the state of conservation of natural systems"; says Joan Real, head of the team of Conservation Biology, linked to the Department of Evolutionary Biology, Ecology and Environmental Sciences of the Faculty of Biology and IRBio. "Knowing the factors that can interact with these bioindicators helps us getting information to improve the management of natural habitats and environmental sustainability", notes Joan Real.

The new study, published in the journal Agriculture, Ecosystems and Environment provides practical information for the sector of ecological viticulture and will help shape a management for a "more sustainable agricultural production regarding biodiversity conservation in the rural environment, and in particular, those birds that are endangered due the agricultural intensification and climate change", notes Antonio Hernández-Matías.

Since 1992, the Biology Conservation Group (UB-IRBio) and Torres Family Foundation, from the company with the same name, have launched several research projects and initiatives in the field of conservation of natural heritage and the design of new management tools for the conservation of biodiversity with a global and efficient perspective.

Some wetlands perform better under pressure. A new study revealed that when faced with sea-level rise, coastal wetlands respond by burying even more carbon in their soils.

Coastal wetlands, which include marshes, mangroves and seagrasses, already store carbon more efficiently than any other natural ecosystem, including forests. The latest study, published March 7 in the journal Nature, looked at how coastal wetlands worldwide react to rising seas and discovered they can rise to the occasion, offering additional protection against climate change.

"Scientists know a fair amount about the carbon stored in our local tidal wetlands, but we didn't have enough data to see global patterns," said Pat Megonigal, a co-author and soil scientist at the Smithsonian Environmental Research Center.

To get a global picture, scientists from Australia, China, South Africa and the U.S. pooled data from 345 wetland sites on six continents. They looked at how those wetlands stored carbon for up to 6,000 years and compared whether sea levels rose, fell or stayed mostly the same over the millennia.

For wetlands that had faced rising seas, carbon concentrations doubled or nearly quadrupled in just the top 20 centimeters of soil. When the scientists looked deeper, at 50 to 100 centimeters beneath the surface, the difference hit five to nine times higher.

The extra boost comes because the carbon added to wetland soils by plant growth and sediment is buried faster as wetlands become wetter. Trapped underwater with little to no oxygen, the organic detritus does not decompose and release carbon dioxide as quickly. And the higher the waters rise, the more underwater storage space exists for the carbon to get buried.

North America and Europe faced the most sea-level rise over the past 6,000 years. Melting glaciers from the last ice age caused water levels to rise, increasing coastal flooding. Continents in the southern hemisphere, by contrast, were largely glacier-free and experienced stable or even falling sea levels.

However, the scene is changing now. The steady march of climate change is exposing even wetlands farther south to accelerated sea-level rise.

"They may be the sleeping giants of global carbon sequestration," said lead author Kerrylee Rogers of the University of Wollongong in Australia. Half of the world's tidal marshland grows along the coastlines of southern Africa, Australia, China and South America. If those wetlands doubled their carbon sequestration--as other wetlands in the study did in response to sea-level rise--they could sequester another 5 million tons of atmospheric carbon every year. That is the equivalent of taking more than a million cars off the road.

The trick, of course, is to ensure wetlands do not drown and disappear if waters rise too quickly.

"Preservation of coastal wetlands is critical if they are to play a role in sequestering carbon and mitigating climate change," Rogers said.

For coastal wetlands to survive, they need space to migrate inland. Whether they have enough space depends largely on how societies prioritize many competing goals. One thing is certain: With climate change ramping up, wetlands can protect people in more ways than one, if given enough breathing room.

Physicists have used a seven-qubit quantum computer to simulate the scrambling of information inside a black hole, heralding a future in which entangled quantum bits might be used to probe the mysterious interiors of these bizarre objects.

Scrambling is what happens when matter disappears inside a black hole. The information attached to that matter -- the identities of all its constituents, down to the energy and momentum of its most elementary particles -- is chaotically mixed with all the other matter and information inside, seemingly making it impossible to retrieve.

This leads to a so-called "black hole information paradox," since quantum mechanics says that information is never lost, even when that information disappears inside a black hole.

So, while some physicists claim that information falling through the event horizon of a black hole is lost forever, others argue that this information can be reconstructed, but only after waiting an inordinate amount of time -- until the black hole has shrunk to nearly half its original size. Black holes shrink because they emit Hawking radiation, which is caused by quantum mechanical fluctuations at the very edge of the black hole and is named after the late physicist Stephen Hawking.

Unfortunately, a black hole the mass of our sun would take about 1067 years to evaporate -- far, far longer than the age of the universe.

However, there is a loophole -- or rather, a wormhole -- out of this black hole. It may be possible to retrieve this infalling information significantly faster by measuring subtle entanglements between the black hole and the Hawking radiation it emits.

Two bits of information -- like the quantum bits, or qubits, in a quantum computer -- are entangled when they are so closely linked that the quantum state of one automatically determines the state of the other, no matter how far apart they are. Physicists sometimes refer to this as "spooky action at a distance," and measurements of entangled qubits can lead to the "teleportation" of quantum information from one qubit to another.

"One can recover the information dropped into the black hole by doing a massive quantum calculation on these outgoing Hawking photons," said Norman Yao, a UC Berkeley assistant professor of physics. "This is expected to be really, really hard, but if quantum mechanics is to be believed, it should, in principle, be possible. That's exactly what we are doing here, but for a tiny three-qubit `black hole' inside a seven-qubit quantum computer."

By dropping an entangled qubit into a black hole and querying the emerging Hawking radiation, you could theoretically determine the state of a qubit inside the black hole, providing a window into the abyss.

Yao and his colleagues at the University of Maryland and the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, Canada, will report their results in a paper appearing in the March 6 issue of the journal Nature.

Teleportation

Yao, who is interested in understanding the nature of quantum chaos, learned from friend and colleague Beni Yoshida, a theorist at the Perimeter Institute, that recovering quantum information falling into a black hole is possible if the information is scrambled rapidly inside the black hole. The more thoroughly it is mixed throughout the black hole, the more reliably the information can be retrieved via teleportation. Based on this insight, Yoshida and Yao proposed last year an experiment to provably demonstrate scrambling on a quantum computer.

"With our protocol, if you measure a teleportation fidelity that is high enough, then you can guarantee that scrambling happened within the quantum circuit," Yao said. "So, then we called up my buddy, Chris Monroe."

Monroe, a physicist at the University of Maryland in College Park who heads one of the world's leading trapped-ion quantum information groups, decided to give it a try. His group implemented the protocol proposed by Yoshida and Yao and effectively measured an out-of-time-ordered correlation function.

Called OTOCs, these peculiar correlation functions are created by comparing two quantum states that differ in the timing of when certain kicks or perturbations are applied. The key is being able to evolve a quantum state both forward and backward in time to understand the effect of that second kick on the first kick.

Monroe's group created a scrambling quantum circuit on three qubits within a seven-qubit trapped-ion quantum computer and characterized the resulting decay of the OTOC. While the decay of the OTOC is typically taken as a strong indication that scrambling has occurred, to prove that they had to show that the OTOC didn't simply decay because of decoherence -- that is, that it wasn't just poorly shielded from the noise of the outside world, which also causes quantum states to fall apart.

Yao and Yoshida proved that the greater the accuracy with which they could retrieve the entangled or teleported information, the more stringently they could put a lower limit on the amount of scrambling that had occurred in the OTOC.

Monroe and his colleagues measured a teleportation fidelity of approximately 80 percent, meaning that perhaps half of the quantum state was scrambled and the other half decayed by decoherence. Nevertheless, this was enough to demonstrate that genuine scrambling had indeed occurred in this three-qubit quantum circuit.

"One possible application for our protocol is related to the benchmarking of quantum computers, where one might be able to use this technique to diagnose more complicated forms of noise and decoherence in quantum processors," Yao said.

Yao is also working with a UC Berkeley group led by Irfan Siddiqi to demonstrate scrambling in a different quantum system, superconducting qutrits: quantum bits that have three, rather than two, states. Siddiqi, a UC Berkeley professor of physics, also leads the effort at Lawrence Berkeley National Laboratory to build an advanced quantum computing test bed.

"At its core, this is a qubit or qutrit experiment, but the fact that we can relate it to cosmology is because we believe the dynamics of quantum information is the same," he said. "The U.S. is launching a billion-dollar quantum initiative, and understanding the dynamics of quantum information connects many areas of research within this initiative: quantum circuits and computing, high energy physics, black hole dynamics, condensed matter physics and atomic, molecular and optical physics. The language of quantum information has become pervasive for our understanding of all these different systems."

Aside from Yao, Yoshida and Monroe, other co-authors are UC Berkeley graduate student T. Schuster and K. A. Landsman, C. Figgatt and N. M. Linke of Maryland's Joint Quantum Institute. The work was supported by the Department of Energy and the National Science Foundation.

Tropical Cyclone Haleh continued to move in a southerly direction in the Southern Indian Ocean when NASA-NOAA's Suomi NPP satellite passed overhead.

Suomi NPP passed over Haleh on March 6 and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument provided a visible image of the storm. The VIIRS image showed a large area of thunderstorms wrapping into the center and the storm appeared to be elongating toward the southeast. The elongation of the storm is a result of outside winds, or moderate to strong vertical wind shear, and is indicative of weakening.

On March 6 at 10 a.m. EDT (1500 UTC) Haleh was located at 23.9 degrees south and 68.7 degrees east. That's about 690 nautical miles east-southeast of Port Louis, Mauritius, has tracked southwestward. Maximum sustained winds had decreased to 75 knots (86 mph/139 kph).

Haleh is forecast to transition into an extra-tropical storm in two days and continue weakening.

Physicists from the University of Sheffield have discovered that when two atomically thin graphene-like materials are placed on top of each other their properties change, and a material with novel hybrid properties emerges, paving the way for design of new materials and nano-devices.

This happens without physically mixing the two atomic layers, nor through a chemical reaction, but by attaching the layers to each other via a weak so called van der Waals interaction - similar to how a sticky tape attaches to a flat surface.

In the ground-breaking study published in Nature, scientists have also found that the properties of the new hybrid material can be precisely controlled by twisting the two stacked atomic layers, opening the way for the use of this unique degree of freedom for the nano-scale control of composite materials and nano-devices in future technologies.

The idea to stack layers of different materials to make so-called heterostructures goes back to the 1960s, when semiconductor gallium arsenide was researched for making miniature lasers - which are now widely used.

Today, heterostructures are common and are used very broadly in semiconductor industry as a tool to design and control electronic and optical properties in devices.

More recently in the era of atomically thin two-dimensional (2D) crystals, such as graphene, new types of heterostructures have emerged, where atomically thin layers are held together by relatively weak van der Waals forces.

The new structures nicknamed 'van der Waals heterostructures' open a huge potential to create numerous 'meta'-materials and novel devices by stacking together any number of atomically thin layers. Hundreds of combinations become possible otherwise inaccessible in traditional three-dimensional materials, potentially giving access to new unexplored optoelectronic device functionality or unusual material properties.

In the study researchers used van der Waals heterostructures made out of so-called transition metal dichalcogenides (TMDs), a broad family of layered materials. In their three-dimensional bulk form they are somewhat similar to graphite - the material used in pencil leads - from where graphene was extracted as a single 2D atomic layer of carbon.

The researchers found that when two atomically thin semiconducting TMDs are combined in a single structure their properties hybridise.

Professor Alexander Tartakovskii, from the Department of Physics and Astronomy at the University of Sheffield, said: "The materials influence each other and change each other's properties, and have to be considered as a whole new 'meta'-material with unique properties - so one plus one doesn't make two.

"We also find that the degree of such hybridisation is strongly dependent on the twist between the individual atomic lattices of each layer.

"We find that when twisting the layers, the new supra-atomic periodicity arises in the heterostructure - called a moiré superlattice.

"The moiré superlattice, with the period dependent on the twist angle governs how the properties of the two semiconductors hybridise."

In other studies, similar effects have been discovered and studied mostly in graphene, the 'founding' member of the 2D materials family. The latest study shows that other materials, in particular semiconductors such as TMDs, show strong hybridisation, that in addition can be controlled by the twist angle.

Scientists believe the study shows huge potential for the creation of new types of materials and devices.

Professor Tartakovskii added: "The more complex picture of interaction between atomically thin materials within van der Waals heterostructures emerges. This is exciting, as it gives the opportunity to access an even broader range of material properties such as unusual and twist-tunable electrical conductivity and optical response, magnetism etc. This could and will be employed as new degrees of freedom when designing new 2D-based devices."

Researchers would like to do further studies to explore more material combinations to see what the capabilities of the new method are.

It's the small pieces that make the big picture, and in this case, the pieces can't be seen by the naked eye. New research at the Okinawa Institute of Science and Technology Graduate University (OIST) used microscopy techniques to piece together the brain of the millimeter-long Caenorhabditis elegans, revealing that their neurons fire action potentials - a spike in voltage due to neurons sending sensory information in the cell membrane. Their results could lead to better understanding of how nerve signals are transmitted in the organism and serve as a future model for neuronal information processing in other animals, including humans.

Scientists from the Information Processing Biology Unit (IPBU) and the Neurobiology Research Unit (NRU) at OIST collaborated on the project. The IPBU had the technology to genetically modify C. elegans, while the NRU had the know-how to record electrical signals from the worm's tiny neurons. Although generally thought to lack the ability to fire action potentials - the all-or-none pulses needed for decision-making - Prof. Ichiro Maruyama, principal investigator of the IPBU, had results that suggested the worm's neurons did fire action potentials. To confirm his suspicions, he wanted further data using electrophysiology, which his lab was not actively doing, so he shared his ideas with Prof. Jeff Wickens, head of the NRU and researchers Tomomi and Mayumi Shindou.

Seven years later, the collaboration paid off; the completed study was published in Scientific Reports on March 5, 2019. Before the project, the common perception was that C. elegans neurons only responded in a graded way with analog signals. The work showed, however, that the neurons would fire an action potential if they crossed a threshold, a more digital type of signaling.

"The main thing this paper shows is that the neurons we study fire action potentials," Wickens said. "Now C. elegans neurons have both active and passive transmission, so all these mechanisms are essential for sensory processing, even in the smallest of neurons."

To observe sensory processing in C. elegans, Maruyama and his team applied salt to the tip of the worm's nose. They increased and decreased the salt concentration, seeking different reactions from the worm and monitoring the electroactivity of its neurons. They found that an increase in salt first affected a neuron on the left side of the brain, then triggered signals causing the worm to move forward. A decrease caused a neuron on the right side to send signals for the worm to move backwards.

"This pair of neurons have the same structure and name, but completely opposite functions," Maruyama said. "Using those two neurons together is very efficient for the worm to reach a place with a preferable salt concentration."

Developing Miniscule Methods

Researching C. elegans imposes a challenge - to give perspective on how small the brain of C. elegans is they have 302 neurons, an ant has 250,000 and a mouse has 75 million. Wickens put his former postdoc and first author of the paper, Dr. Tomomi Shindou, in charge of developing the methodology for the project. The work took time - four years of trial and error to create the right techniques, and three more for collecting data.

The NRU created a sharp glass needle less than the size of a micrometer. They used the needle to extract a brain cell from C. elegans once it was exposed to salt to view the neuron. This method is like using tweezers to extract a splinter from a finger.

"Only a handful of labs in the world can do this," Maruyama said. "Once the cell was extracted, the scientists used electrophysiology - measuring voltage change in cells to track neurons viewing active and passive activation. The scientists also used calcium imaging to produce more data, and observed freely-moving worms that had been exposed to the salt.

"You can express a calcium sensor protein in a particular neuron - if the neuron is activated it will light up," Maruyama said. "Once neurons are activated, they produce a green fluorescence and now you are detecting the neuron activity with the fluorescent microscope. The data from the two tests perfectly matched."

"Perfectly matched data" is a phrase every researcher hopes to hear. The results suggest that the accepted dogma--that these worms only send passive signals--is wrong. The remarkable finding also opens a door to improved neural mapping in the future.

"Every C. elegans has the same set of neurons connected in the same way, unlike a mouse brain which is a jungle of connections," Wickens said. "If we can get a better understanding of this simple nervous system, for which we have a kind of circuit diagram, we can get insights on how more complicated brains operate at a bigger scale."

In the 1970s and 80s it was normal for children to 'play out' on the street in British towns and cities. However nowadays young people are far more likely to spend their time indoors, inactive and isolated.

As a result, children's physical activity levels are at an all-time low, with only one in five children getting the minimum recommended 1 hour a day of moderate to vigorous physical exercise.

However, for the last 10 years a grassroots organisation called 'Playing Out' has been working hard to change this, allowing children across the UK to take back their streets.

In an upcoming special edition of the Routledge journal Cities & Health, Alice Ferguson writes about why and how she, with other local parents, first set up 'Playing Out'.

"I grew up in the city, and a lot of time was spent just playing out with friends, on my own street and around the neighbourhood. This was the norm for most children in the 1970s. At the time, it was just about getting out of the house and having fun, but without realising it we were also getting a lot of physical activity, developing resilience and social skills, getting to know our local 'patch' and gaining independence."

"A group of parents in my neighbourhood felt strongly that we wanted our children to have the same freedom and sense of belonging in their community that we'd had in our own childhoods. We looked around and realised that playing out was no longer normal - so we decided to do something about it."

In 2009 Ferguson and her neighbours decided to create a temporary 'play street' for a few hours one day after school. They formally closed their road to through traffic using the council's existing road closure procedure.

The following summer, the group ran a pilot where they supported other residents on six local streets to do the same, allowing more children to play outside. Local politicians got behind the idea, and the council developed a 'Temporary Play Street Order' (TPSO), which allowed residents to apply for a whole year's worth of regular closures in one go.

Since then, 59 other UK councils have followed suit, enabling over 800 street communities across the UK to organise regular playing out sessions, directly benefiting an estimated 24,000 children. Playing Out supports all this through providing free advice and resources for residents, councils and community organisations, as well as building a peer-support network of parents and 'activators' around the country.

In Cities & Health, Ferguson writes about the impact that 'Playing Out' has had on children's lives and their communities. Research by Bristol University has shown that Playing Out has raised kids' physical activity levels - children are three to five times more active when playing out than they would be on a 'normal' day after school; brought neighbourhoods together; reduced social isolation; and helped residents become more actively involved in their communities.

Perhaps the most notable impact of Playing Out has been to change the way people view children's right to play on their street. Through media coverage and direct engagement with communities, this parent-led movement has made children playing out more visible and 'normal', removing some of the barriers preventing parents from allowing their children to play outside.

However, to continue this momentum of cultural change, Ferguson believes policies are needed that will make streets, estates and neighbourhoods safer places for children to play on a more permanent basis.

"We only ever intended this model as an interim, emergency measure. Being able to play out on your own street once a week or once a month, closely supervised by adults, is a poor replacement for 'real' playing out; the freedom to just go out your front door, meet up with your mates, have an adventure and come home when dinner is ready. Our long-term vision is for all children to have the freedom to play out where they live, every day."

"To do this we must tackle the root causes of the problem. Amongst other things, this will inevitably involve reducing the dominance of cars in our streets and cities, something politicians have been reluctant to do - but we are starting to see a shift in the right direction".

Smaller beetles who consistently lose fights over resources can gain a competitive advantage over their larger rivals by teaming up with another species.

In a study featuring a miniature 'gym' for beetles (complete with beetle treadmills), researchers from the University of Cambridge found that beetles who consistently lose out to members of their own species have the most to gain by forming a mutually-beneficial cross-species partnership.

The researchers studied the relationship between the burying beetle and the tiny mites that hitch a ride on their backs. The researchers found that mites function like a warm jacket on smaller beetles, and cause them to heat up when the beetles exercise. This made them more successful in face-offs with larger opponents.

For larger beetles, the mites actually reduced their level of fitness. They needed no help from mites to win ownership of a dead body and then lost out because the beetle larvae had to compete with mites for food. The results are reported in the journal Evolution Letters.

Relationships between two species where both benefit - such as flowering plants pollinated by insects - is known as mutualism. These relationships are widespread and are key to maintaining biodiversity and ecosystem function, but they are highly variable.

"When the costs of a mutualistic relationship start to outweigh the benefits, it will break down," said Syuan-Jyun Sun, a PhD candidate in Cambridge's Department of Zoology and the paper's first author. "We wanted to find out if competition within species might be one of the reasons why we see such variety in mutualistic relationships."

In competition for food or a mate, there will inevitably be winners and losers. The Cambridge researchers wanted to test whether 'losers' might be more likely to have a mutualistic relationship with another species in order to gain an advantage over their stronger rivals. At the same time, 'winners' may not need any help to win battles, so a mutualistic relationship wouldn't bring any advantage and might even break down into a form of parasitism.

The researchers tested this idea with experiments on burying beetles and their mites. The mites Poecilochirus carabi are benign passengers on their host burying beetles Nicrophorus vespilloides. The beetle flies around, seeking out the bodies of freshly dead small animals like mice and birds. Both the beetle and the mites onboard use the dead body as food for their young.

However, beetles face fierce competition for the ownership of a carcass, such as a dead mouse, and smaller beetles often lose the territory to larger rivals. Since the beetles need the carcass to breed, how do smaller beetles manage to reproduce?

"We wondered whether mites could give these 'losers' a helping hand in fights over a carcass," said Sun. In the lab of Professor Rebecca Kilner in Cambridge, the researchers staged contests over a dead mouse between two beetles that were matched in size. One carried mites, while the other did not. They filmed the fights with infrared thermography, and found that beetles with mites were hotter and more aggressive, and therefore more likely to win.

To investigate how such thermal benefits arose, the researchers built a 'gym' for beetles, and exercised them on custom treadmills. Beetles either carried mites, or a weight that was equivalent to the mites, or they carried nothing.

"We found that carrying extra weight caused beetles to generate extra heat as they exercised," said Sun. "We also discovered that this heat was trapped by the mites, because the mites form an insulating layer when travelling on beetles."

These effects were most pronounced for smaller beetles because mites covered a relatively larger surface area than on large beetles, suggesting that mites are likely to be disproportionally beneficial to smaller beetles.

To test this idea directly, the researchers again staged fights between two beetles over a dead mouse. This time, the two rivals differed in body size. They also let beetles lay their eggs on a mouse, with and without mites.

The researchers found that small beetles were much more likely to win a fight for a carcass when they were carrying mites. However, the mites slightly reduced the beetles' reproductive success, because they competed with beetle larvae for carrion. Nevertheless, the huge benefits of acquiring a carcass for reproduction outweighed these small costs. For smaller 'loser' beetles, mites are mutualists because they increase beetle fitness.

The findings were different for larger beetles. They needed no help to win a carcass, so they gained nothing from associating with mites. To make matters worse, they then lost fitness to the mites when they bred alongside each together on the carcass. For larger 'winner' beetles, mites are antagonistic rather than mutualistic because they reduce beetle fitness.

Researchers at Tokyo Institute of Technology (Tokyo Tech) have developed an easy-to-use, tunable biosensor tailored for the terahertz range. Images of mouse organs obtained using their new device verify that the sensor is capable of distinguishing between different tissues. The achievement expands possibilities for terahertz applications in biological analysis and future diagnostics.

Plasmonics is a term that describes both the study and applications of phenomena related to the interaction between light and metal surface electrons. Plasmonic-based materials are of interest in the development of technologies ranging from high-performance electronics to ultra-sensitive biosensors.

Scientists are exploring the possibilities of combining the advantages of plasmonics with emerging terahertz technologies as a way of developing new and enhanced methods for non-invasive detection and analysis. So far, however, the ability to detect tiny, biological samples has proven challenging, mainly because THz light waves have longer wavelengths than visible, infrared and ultraviolet light.

Now, Yukio Kawano and colleagues at Tokyo Tech's Laboratory for Future Interdisciplinary Research of Science and Technology working in collaboration with researchers at Tokyo Medical and Dental University have found a way to overcome this barrier by designing a frequency-tunable plasmonic-based THz device.

One of the key features of the new device is its spiral bull's eye (SBE) design (see Figure 1). Due to its smoothly varied grooves, "the groove period continuously changes with the diameter direction, resulting in continuously frequency-tunable characteristics," Kawano says in their study published in Scientific Reports.

Another advantage of the new design is that it incorporates a so-called Siemens-star aperture, which enables a user-friendly way of selecting the desired frequency by simply changing the rotation of the spiral plasmonic structure.

"The device also increases the electric field intensity at the subwavelength aperture, thus significantly amplifying the transmission," Kawano says.

In preliminary experiments to assess how well the new device could visualize biological tissues, the researchers obtained THz transmission spectra for various mouse organs, as shown in Figure 2. To probe further, they also conducted THz mapping of mouse tails. By comparing images obtained with and without the SBE design, the study showed that the former led to a markedly improved ability to distinguish between different tissues such as hair, skin and bone (see Figure 3). The findings suggest that the improved performance is due to the device’s tunability.

It's one thing for humans to lose track of time, but what happens when our clocks do In an increasingly networked world, devices need to be more punctual than ever. To keep them running as we expect, they depend on an army of tiny, vibrating components.

A finding from a team led by scientists at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) user facility at Argonne National Laboratory, could ultimately help improve such components in a range of electronics and even create devices that mimic biological processes. The researchers have pioneered a micromechanical device that responds to external signals in an entirely new way compared to conventional ones. Their work, conducted by a team spanning five institutions including Argonne, was recently published in the journal Physical Review Letters.

"The novelty here is if you excite this resonator device in the right way, the structure vibrates with a spectrum consisting of multiple frequencies evenly spaced, in spite of the fact that it is driven by a single frequency." — Daniel Lopez, group leader for the Center for Nanoscale Materials’ Nanofabrication and Devices group

A typical resonator in an electronic device responds to one signal with one corresponding frequency. In wristwatches, for example, a quartz resonator vibrates at a specific frequency when a certain voltage is applied, and that vibration marks the time. But a multitasking network of devices might require responses at more than one frequency, and that's where things get tricky.

"For every device running at a specific frequency, you need a timing source," said CNM nanoscientist Dave Czaplewski, the paper's lead author. "Having multiple devices running at multiple frequencies makes the system much more complex."

While a common approach to this problem involves multiple resonators, multiple signals or both, the researchers created a single, microsize resonator that can generate multiple frequencies from one signal. This set of frequencies is called a frequency comb, so named for the way the frequencies appear evenly spaced, like teeth, when plotted on a graph.  

"The novelty here is if you excite this resonator device in the right way, the structure vibrates with a spectrum consisting of multiple frequencies evenly spaced, in spite of the fact that it is driven by a single frequency," said Daniel Lopez, group leader for CNM’s Nanofabrication and Devices group and a co-author of the paper. "Instead of fabricating a specific oscillator for each device, you could fabricate a single oscillator that can produce a signal at all the different frequencies needed."

The research was conducted partly at the CNM, where researchers designed the resonator and used electrical characterization techniques to measure its responses. The silicon device, which is no bigger than a few grains of salt laid end to end, anchors three beams that move together in two vibrations: a side-to-side swaying motion and a twisting motion. The researchers used this duality to generate the frequency comb.

"We use the interplay between those two vibrations to obtain this frequency response that ends up looking like a frequency comb," Czaplewski said.

Frequency combs are more commonly used in the field of optics, where they consist of laser light pulses and can be used to measure time accurately. In another application, this mechanical frequency comb, the researchers said, can be used to study a specific type of dynamic known as a SNIC bifurcation (saddle node on an invariant circle) in mechanical, optical and biological systems. In a biological setting, for example, understanding this behavior could aid in the design of micromechanical elements that emulate the way neurons respond to stimuli. The mathematics describing the vibrations in this resonator were carried out in collaboration with a team of experts in the field of nonlinear dynamics at multiple universities.  

The next step in the research, Lopez said, will be to reproduce the frequency comb phenomenon in higher-frequency resonators and extend the number of "teeth" — or frequencies — that can be generated.

Not every embryo contains 46 perfect chromosomes. Some have more, others have fewer. The result is a common abnormality known as aneuploidy, which occurs in as many as 80 percent of human embryos.

Because aneuploidy has been linked to a risk of in vitro fertilization failure, miscarriage and certain genetic orders or birth defects, mosaic embryos, those with both normal and abnormal cells, have not been considered ideal candidates for IVF transfer.

For many individuals who only produce mosaic embryos, this can mean that the IVF journey may end before it begins.

New research conducted by scientists at the Oregon National Primate Research Center at OHSU, in Portland, Oregon, gives new hope to those seeking infertility treatments. Their findings published in the journal Genome Research.

The study, led by Shawn L. Chavez, Ph.D., is the first to confirm in a nonhuman primate model that mosaic embryos can adapt to their abnormalities and persist in development, resulting in positive IVF outcomes.

Using advanced time-lapse imaging and single-cell sequencing techniques to precisely track the development of mosaic embryos of a rhesus macaque, Chavez and team identified a unique relationship between mosaicism and two other biological processes: cell fragmentation and blastomere exclusion.

In utero and after IVF, large cells formed by the division of a fertilized egg, known as blastomeres, may break down into small pieces called cellular fragments.

"We found that both the blastomeres and their fragments can act as trash bins within the embryo. As DNA-carrying cells divide and/or fragment, the embryo appears to naturally identify which blastomeres have genetic abnormalities and stop them from further development, " says Chavez, an assistant professor of reproductive and developmental sciences at ONPRC at OHSU, and an assistant professor of obstetrics and gynecology, and physiology and pharmacology in the OHSU School of Medicine. "By the stage that an embryo would implant into the uterus, these abnormal cells, or DNA have been visibly excluded from the rest of the embryo, suggesting that imperfect IVF embryos could be considered for use in transfer and might have the ability to endure in utero."

According to Paula Amato, M.D., an associate professor of obstetrics and gynecology in the OHSU School of Medicine, this discovery could positively impact IVF processes for humans in the future.

"While selecting embryos with a normal chromosome complement is preferred and carries a high chance of pregnancy success, it is not a guarantee. For patients with only mosaic embryos available for transfer, these findings suggest that in some cases, these embryos will result in apparently normal pregnancies."

Ongoing research will use live-cell time-lapse imaging to better understand the relationship between aneuploidy, cell fragmentation and blastomere exclusion within the embryo. The scientists believe these results could open up new avenues for testing the efficacy of mosaic human embryos.

"We expect that the overall results will be similar to the story of the 'dark horse,' said Chavez. "While not perceived as a contender at the start of the IVF race, a mosaic embryo may still be capable of winning and resulting in something wonderful."

Rice University physicists Matthew Foster and Seth Davis want to view a vexing quantum puzzle from an entirely new perspective. They just need the right vantage point and a place colder than deep space.

"There's a process in strongly interacting physics where fundamental particles, like electrons, can come together and behave as if they were a fraction of an electron," said Davis, a graduate student in Foster's research group. "It's called fractionalization. It's a really exotic, fundamental process that shows up theoretically in many places. It may have something to do with high-temperature superconductivity, and it could be useful for building quantum computers. But it's very hard to understand and even harder to measure."

In a recent paper in Physical Review Letters, Foster and Davis, both theoretical physicists, proposed an experiment to measure fractionalization not in electrons but in atoms so cold they follow the same quantum rules that dictate how electrons behave in quantum materials, a growing class of materials with exotic electronic and physical properties that governments and industry are eying for next-generation computers and electronic devices.

Quantum materials include high-temperature superconductors, one of the most puzzling mysteries in physics, and materials that exhibit topological phases, which earned its discoverers the 2016 Nobel Prize in Physics. The latter is the only place physicists have unambiguously measured fractionalization, in an exotic electronic state called the fractional quantum Hall effect. In this state, flat two-dimensional materials conduct electricity only along their one-dimensional edges.

"That's a 2D example," said Foster, assistant professor of physics and astronomy at Rice. "And it's clear that fractionalization is occurring there because if you measure the conductance of these edge states they behave as though they're made of particles that behave like one-third of an electron.

"There are no real particles carrying one-third of the electric charge," he said. "It's just the effect of all the electrons moving together in a such a way that if you create a local excitation, it will behave like an electron with one-third of a charge."

Foster and Davis said the main motivation for describing their ultracold atomic test was to be able to observe fractionalization in a system that is very different from the fractional quantum Hall example.

"What we're aiming at is just seeing this physics in one other context in an unambiguous way," said Foster, a member of Rice's Center for Quantum Materials (RCQM).

Their proposed experiment calls for laser-cooling atoms to act as stand-ins for electrons. In such experiments, lasers oppose the motion of atoms, progressively slowing them to colder and colder temperatures. The cold atoms are trapped by other lasers that form optical waveguides, one-dimensional channels where atoms can move left or right but cannot go around one another. The quantum behavior of the atoms in these one-dimensional guides mimics the behavior of electrons in 1D wires.

"All of the individual elements of the experiment have been developed, but we don't believe they've been put together in a single experimental setup," Foster said. "That's where we need the help of experimentalists who are experts in laser-cooling."

To observe fractionalization in an ultracold system, Foster and Davis propose creating a set of parallel 1D waveguides that are all in the same two-dimensional plane. A few additional atoms would populate the 1D guides near the center of the experiment.

"So we'll start with the 1D 'wires,' or guides, and the initial density in the middle, and then we'll drop some of the lasers and allow the atoms to interact between the wires in a kind of 2D mesh," Foster said. "We can very accurately describe the 1D system, where strong interactions cause the atoms to behave in a correlated way. Because the whole system is quantum mechanical and coherent, those correlations should get imprinted on the 2D system.

"Our probe is letting go of that extra bump of density and watching what it does," he said. "If the atoms in the 1D guides are not interacting, then the bump will just spread out between the wires. But, if there was initial fractionalization due to correlated effects in the wires, what we can confidently calculate is that the density will do something completely different. It will go the other direction, flying down the wires."

Foster said he's interested in discussing the feasibility of the test with ultracold atomic experimentalists.

"We know it can take years to build and perfect some of the experimental setups for these kinds of experiments," Foster said. "As theorists, we know the ingredients we need, but we don't know the ones that will be most challenging to implement or if it may be easier to modify some setups as opposed to others. That's where we'll need the help of our experimental colleagues."

A popular theme in the movies is that of an incoming asteroid that could extinguish life on the planet, and our heroes are launched into space to blow it up. But incoming asteroids may be harder to break than scientists previously thought, finds a Johns Hopkins study that used a new understanding of rock fracture and a new computer modeling method to simulate asteroid collisions.

The findings, to be published in the March 15 print issue of Icarus, can aid in the creation of asteroid impact and deflection strategies, increase understanding of solar system formation and help design asteroid mining efforts.

"We used to believe that the larger the object, the more easily it would break, because bigger objects are more likely to have flaws. Our findings, however, show that asteroids are stronger than we used to think and require more energy to be completely shattered," says Charles El Mir, a recent Ph.D graduate from the Johns Hopkins University's Department of Mechanical Engineering and the paper's first author.

Researchers understand physical materials like rocks at a laboratory scale (about the size of your fist), but it has been difficult to translate this understanding to city-size objects like asteroids. In the early 2000s, a different research team created a computer model into which they input various factors such as mass, temperature, and material brittleness, and simulated an asteroid about a kilometer in diameter striking head-on into a 25-kilometer diameter target asteroid at an impact velocity of five kilometers per second. Their results suggested that the target asteroid would be completely destroyed by the impact.

In the new study, El Mir and his colleagues, K.T. Ramesh, director of the Hopkins Extreme Materials Institute and Derek Richardson, professor of astronomy at the University of Maryland, entered the same scenario into a new computer model called the Tonge-Ramesh model, which accounts for the more detailed, smaller-scale processes that occur during an asteroid collision. Previous models did not properly account for the limited speed of cracks in the asteroids.

"Our question was, how much energy does it take to actually destroy an asteroid and break it into pieces?" says El Mir.

The simulation was separated into two phases: a short-timescale fragmentation phase and a long-timescale gravitational reaccumulation phase. The first phase considered the processes that begin immediately after an asteroid is hit, processes that occur within fractions of a second. The second, long-timescale phase considers the effect of gravity on the pieces that fly off the asteroid's surface after the impact, with gravitational reaccumulation occurring over many hours after impact.

In the first phase, after the asteroid was hit, millions of cracks formed and rippled throughout the asteroid, parts of the asteroid flowed like sand, and a crater was created. This phase of the model examined the individual cracks and predicted overall patterns of how those cracks propagate. The new model showed that the entire asteroid is not broken by the impact, unlike what was previously thought. Instead, the impacted asteroid had a large damaged core that then exerted a strong gravitational pull on the fragments in the second phase of the simulation.

The research team found that the end result of the impact was not just a "rubble pile" - a collection of weak fragments loosely held together by gravity. Instead, the impacted asteroid retained significant strength because it had not cracked completely, indicating that more energy would be needed to destroy asteroids. Meanwhile, the damaged fragments were now redistributed over the large core, providing guidance to those who might want to mine asteroids during future space ventures.

"It may sound like science fiction but a great deal of research considers asteroid collisions. For example, if there's an asteroid coming at earth, are we better off breaking it into small pieces, or nudging it to go a different direction? And if the latter, how much force should we hit it with to move it away without causing it to break? These are actual questions under consideration," adds El Mir.

"We are impacted fairly often by small asteroids, such as in the Chelyabinsk event a few years ago," says Ramesh. "It is only a matter of time before these questions go from being academic to defining our response to a major threat. We need to have a good idea of what we should do when that time comes - and scientific efforts like this one are critical to help us make those decisions."