When atoms are cooled to temperatures close to absolute zero (-273 degrees C), they stop behaving like particles and start to behave like waves.

Atoms in this condition, which are known as Bose-Einstein condensates (BECs), are useful for purposes such as realisation of atom lasers, slow light, quantum simulations for understanding the complex behaviour of materials like superconductors and superfluids, and the precision measurement technique of atom interferometry.

The Strathclyde study has shown that when twisted light is shone on to a moving BEC, it breaks into clusters of BEC droplets that move following the light’s features, with the number of droplets equal to twice the number of light twists. Altering the properties of the light beam can change both the number of BEC droplets and the way that they move.

The research has been published in Physical Review Letters.

Grant Henderson, a PhD student in Strathclyde’s Department of Physics, is lead author on the paper. He said: “By shining a laser beam on to a BEC, we can influence how it behaves. When the laser beam is ‘twisted,’ it has a helical phase profile and carries orbital angular momentum (OAM). Laser beams with OAM can trap and rotate microscopic particles, behaving like an optical spanner.

“This method of shining twisted light through ultracold atoms opens a new and simple way of sculpting matter into unconventional and complex shapes. It has the potential for the design of novel quantum devices such as atomtronic circuits and ultra-sensitive detectors.”

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The study was conducted in the laboratory of Andy Thompson, professor of environmental science and engineering, and appears in the journal Science Advances on August 12.

Ice shelves are outcroppings of the Antarctic ice sheet, found where the ice juts out from land and floats on top of the ocean. The shelves, which are each several hundred meters thick, act as a protective buffer for the mainland ice, keeping the whole ice sheet from flowing into the ocean (which would dramatically raise global sea levels). However, a warming atmosphere and warming oceans caused by climate change are increasing the speed at which these ice shelves are melting, threatening their ability to hold back the flow of the ice sheet into the ocean.

“If this mechanism that we’ve been studying is active in the real world, it may mean that ice shelf melt rates are 20 to 40 percent higher than the predictions in global climate models, which typically cannot simulate these strong currents near the Antarctic coast,” Thompson says.

In this study, led by senior research scientist Mar Flexas, the researchers focused on one area of Antarctica: the West Antarctic Peninsula (WAP). Antarctica is roughly shaped like a disk, except where the WAP protrudes out of the high polar latitudes and into lower, warmer latitudes. It is here that Antarctica sees the most dramatic changes due to climate change. The team has previously deployed autonomous vehicles in this region, and scientists have used data from instrumented elephant seals to measure temperature and salinity in the water and ice.

The team’s model takes into account the narrow Antarctic Coastal Current that runs counterclockwise around the entire Antarctic continent, a current which many climate models do not include because it is so small.

“Large global climate models don’t include this coastal current, because it’s very narrow — only about 20 kilometers wide, while most climate models only capture currents that are 100 kilometers across or larger,” Flexas explains. “So, there is a potential for those models to not represent future melt rates very accurately.”

The model illustrates how freshwater that melts from ice at the WAP is carried by the coastal current and transported around the continent. The less-dense freshwater moves along quickly near the surface of the ocean and traps relatively warm ocean saltwater against the underside of the ice shelves. This then causes the ice shelves to melt from below. In this way, increased meltwater at the WAP can propagate climate warming via the Coastal Current, which in turn can also escalate melting even at West Antarctic ice shelves thousands of kilometers away from the peninsula. This remote warming mechanism may be part of the reason that the loss of volume from West Antarctic ice shelves has accelerated in recent decades.

“There are aspects of the climate system that we are still discovering,” Thompson says. “As we’ve made progress in our ability to model interactions between the ocean, ice shelves, and atmosphere, we’re able to make more accurate predictions with better constraints on uncertainty. We may need to revisit some of the predictions of sea level rise in the next decades or century — that’s work that we’ll do going forward.”

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“Most repairs focus on the tendon,” and how to reattach it to the bone most effectively, Laurencin says. “But the real problem is that the muscle degenerates and accumulates fat. With a tear, the muscle shrinks, and the body grows fat in that area instead. When the tendon and muscle are finally reattached surgically to the shoulder bone, the weakened muscle can’t handle normal stresses and the area can be re-injured again.

Dr. Laurencin along with graduate student Nikoo Shemshaki worked with other UConn Connecticut Convergence Institute researchers to develop a polymer mesh infused with nanoplatelets of graphene. When they used it to repair the shoulders of rats who had chronic rotator cuff tears with muscle atrophy, the muscle grew back. When they tried growing muscle on the mesh in a petri dish in the lab, they found the material seemed to encourage the growth of myotubes, precursors of muscle, and discourage the formation of fat.

“This is really a potential breakthrough treatment for tears of the rotator cuff. It addresses the real problem: muscle degeneration and fat accumulation,” Laurencin says.

The next step in their work is studying the matrix in a large animal. The team looks forward to developing the technology in humans.

This work was funded by NIH National Institute of Arthritis and Musculoskeletal and Skin Diseases Grant No. DP1AR068147 and National Science Foundation Emerging Frontiers in Research and Innovation Grant No. 1332329.

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Powered by computational image processing, the camera can decipher the size and shape of objects hidden around corners or behind other items. The technology could be incorporated into autonomous vehicles or medical imaging tools with sensing capabilities far beyond what is considered state of the art today. This research has been published in Nature Communications.

In the dark, bats can visualize a vibrant picture of their surroundings by using a form of echolocation, or sonar. Their high-frequency squeaks bounce off their surroundings and are picked back up by their ears. The minuscule differences in how long it takes for the echo to reach the nocturnal animals and the intensity of the sound tell them in real time where things are, what’s in the way and the proximity of potential prey.

Many insects have geometric-shaped compound eyes, in which each “eye” is composed of hundreds to tens of thousands of individual units for sight — making it possible to see the same thing from multiple lines of sight. For example, flies’ bulbous compound eyes give them a near-360-degree view even though their eyes have a fixed focus length, making it difficult for them to see anything far away, such as a flyswatter held aloft.

Inspired by these two natural phenomena found in flies and bats, the UCLA-led team set out to design a high-performance 3D camera system with advanced capabilities that leverage these advantages but also address nature’s shortcomings.

“While the idea itself has been tried, seeing across a range of distances and around occlusions has been a major hurdle,” said study leader Liang Gao, an associate professor of bioengineering at the UCLA Samueli School of Engineering. “To address that, we developed a novel computational imaging framework, which for the first time enables the acquisition of a wide and deep panoramic view with simple optics and a small array of sensors.”

Called “Compact Light-field Photography,” or CLIP, the framework allows the camera system to “see” with an extended depth range and around objects. In experiments, the researchers demonstrated that their system can “see” hidden objects that are not spotted by conventional 3D cameras.

The researchers also use a type of LiDAR, or “Light Detection And Ranging,” in which a laser scans the surroundings to create a 3D map of the area.

Conventional LiDAR, without CLIP, would take a high-resolution snapshot of the scene but miss hidden objects, much like our human eyes would.

Using seven LiDAR cameras with CLIP, the array takes a lower-resolution image of the scene, processes what individual cameras see, then reconstructs the combined scene in high- resolution 3D imaging. The researchers demonstrated the camera system could image a complex 3D scene with several objects, all set at different distances.

“If you’re covering one eye and looking at your laptop computer, and there’s a coffee mug just slightly hidden behind it, you might not see it, because the laptop blocks the view,” explained Gao, who is also a member of the California NanoSystems Institute. “But if you use both eyes, you’ll notice you’ll get a better view of the object. That’s sort of what’s happening here, but now imagine seeing the mug with an insect’s compound eye. Now multiple views of it are possible.”

According to Gao, CLIP helps the camera array make sense of what’s hidden in a similar manner. Combined with LiDAR, the system is able to achieve the bat echolocation effect so one can sense a hidden object by how long it takes for light to bounce back to the camera.

The co-lead authors of the published research are UCLA bioengineering graduate student Yayao Ma, who is a member of Gao’s Intelligent Optics Laboratory, and Xiaohua Feng — a former UCLA Samueli postdoc working in Gao’s lab and now a research scientist at the Research Center for Humanoid Sensing at the Zhejiang Laboratory in Hangzhou, China.

The research was supported by the National Institute of General Medical Sciences, which is part of the National Institutes of Health.

ADHD, which affects more than 10 percent of U.S. school-age children, according to the Centers for Disease Control and Prevention, manifests early in childhood with symptoms of hyperactivity, impulsivity or inattention, and has known links to preterm birth (less than 37 weeks gestation). The study, published in the Journal of Pediatrics, is one of only a few to investigate the associations between gestational age at term (37-41 weeks) and a diagnosis or symptoms of ADHD. It is the first to include reports from teachers.

“Teachers’ reports, in conjunction with maternal reports and physician evaluations, provide valuable input for the diagnosis of ADHD,” said Nancy Reichman, author of the study and a professor of pediatrics at Rutgers Robert Wood Johnson Medical School. “Mother-reported symptoms generally reflect behaviors in the home or in small family or social groups, while teacher-reported symptoms reflect behaviors in a structured educational setting by professionals who work with a large number of children and observe the range of behaviors that students exhibit in classrooms.”

Reichman and her team, which included Rutgers Robert Wood Johnson Medical School neonatology fellow Geethanjali Linguasubramanian, sought to estimate the associations between gestational age at term and 9-year-old children’s symptoms of ADHD reported by their teachers.

They analyzed data on about 1,400 children in the Fragile Families and Child Wellbeing study, a U.S. birth cohort study that randomly sampled births in 75 hospitals in 20 large U.S. cities from 1998 to 2000 and re-interviewed mothers over nine years. During the nine-year follow-up, consent was obtained to contact the children’s teachers, who were asked to evaluate their students using the Conners’ Teacher Rating Scale-Revised Short Form, which includes symptoms of hyperactivity, ADHD, oppositional behavior and cognitive problems or inattention.

Overall, the Rutgers researchers found that children born early-term (37-38 weeks) had significantly higher scores on the teacher rating scales than children who were full-term (39-41 weeks) for hyperactivity, ADHD and cognitive problems or inattention, but that gestational age wasn’t significantly associated with oppositional behavior.

Specifically, the researchers found that each week of gestational age at term was associated with 6 percent lower hyperactivity scores and 5 percent lower ADHD and cognitive problems or inattention scores, and that birth at 37 to 38 weeks was associated with 23 percent higher hyperactivity scores and 17 percent higher ADHD scores when compared with birth at 39 to 41 weeks.

“The findings add to growing evidence supporting current recommendations for delaying elective deliveries to at least 39 weeks and suggest that regular screenings for ADHD symptoms are important for children born at 37 to 38 weeks,” Reichman said.

Preterm infants are at increased risk for ADHD because of immature brain development, she said. “Significant growth and development in various kinds of brain cells are observed between 34 and 40 weeks of gestation,” said Reichman. “Infants born at full-term likely benefit from the additional one to two weeks of brain growth in utero compared with those born early-term.”

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On average, the group with the polytherapeutic (31 people) showed clinically significant improvements at 12 weeks, while the other group (30 people) did not. The results have just been published in Frontiers in Neurology. “This is more significant than some of our earlier work and is likely to have a direct impact on future treatment of tinnitus,” Associate Professor in Audiology Grant Searchfield says.

Key to the new treatment is an initial assessment by an audiologist who develops the personalised treatment plan, combining a range of digital tools, based on the individual’s experience of tinnitus. “Earlier trials have found white noise, goal-based counselling, goal-oriented games and other technology-based therapies are effective for some people some of the time,” says Dr Searchfield. “This is quicker and more effective, taking 12 weeks rather than 12 months for more individuals to gain some control.”

There is no pill that can cure tinnitus. “What this therapy does is essentially rewire the brain in a way that de-emphasises the sound of the tinnitus to a background noise that has no meaning or relevance to the listener,” Dr Searchfield says.

Audiology research fellow Dr Phil Sanders says the results are exciting and he found running the trial personally rewarding.

“Sixty-five percent of participants reported an improvement. For some people, it was life-changing — where tinnitus was taking over their lives and attention.”

Some people didn’t notice an improvement and their feedback will inform further personalisation, Dr Sanders says.

Tinnitus is a phantom noise and its causes are complex. It has so far defied successful treatment.

While most people experience tinnitus, or ringing in the ears at least on occasions, around five percent experience it to a distressing degree. Impacts can include trouble sleeping, difficulty carrying out daily tasks and depression.

Dr Searchfield says seeing his patients’ distress and having no effective treatment to offer inspired his research. “I wanted to make a difference.”

The next step will be to refine the prototype and proceed to larger local and international trials with a view to FDA approval.

The researchers hope the app will be clinically available in around six months.

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The Multicentre Epilepsy Lesion Detection project (MELD) used over 1,000 patient MRI scans from 22 global epilepsy centres to develop the algorithm, which provides reports of where abnormalities are in cases of drug-resistant focal cortical dysplasia (FCD) — a leading cause of epilepsy.

FCDs are areas of the brain that have developed abnormally and often cause drug-resistant epilepsy. It is typically treated with surgery, however identifying the lesions from an MRI is an ongoing challenge for clinicians, as MRI scans in FCDs can look normal.

To develop the algorithm, the team quantified cortical features from the MRI scans, such as how thick or folded the cortex/brain surface was, and used around 300,000 locations across the brain.

Researchers then trained the algorithm on examples labelled by expert radiologists as either being a healthy brain or having FCD — dependant on their patterns and features.

The findings, published in Brain, found that overall the algorithm was able to detect the FCD in 67% of cases in the cohort (538 participants).

Previously, 178 of the participants had been considered MRI negative, which means that radiologists had been unable to find the abnormality — yet the MELD algorithm was able to identify the FCD in 63% of these cases.

This is particularly important, as if doctors can find the abnormality in the brain scan, then surgery to remove it can provide a cure.

Co-first author, Mathilde Ripart (UCL Great Ormond Street Institute of Child Health) said: “We put an emphasis on creating an AI algorithm that was interpretable and could help doctors make decisions. Showing doctors how the MELD algorithm made its predictions was an essential part of that process.”

Co-senior author, Dr Konrad Wagstyl (UCL Queen Square Institute of Neurology) added: “This algorithm could help to find more of these hidden lesions in children and adults with epilepsy, and enable more patients with epilepsy to be considered for brain surgery that could cure the epilepsy and improve their cognitive development. Roughly 440 children per year could benefit from epilepsy surgery in England.”

Around 1% of the world’s population have the serious neurological condition epilepsy, that is characterised by frequent seizures.

In the UK some 600,000 people are affected. While drugs treatments are available for the majority of people with epilepsy, 20-30% do not respond to medications.

In children who have had surgery to control their epilepsy, FCD is the most common cause, and in adults it is the third most common cause.

Additionally, of patients who have epilepsy that have an abnormality in the brain that cannot be found on MRI scans, FCD is the most common cause.

Co-first author, Dr. Hannah Spitzer (Helmholtz Munich) said: “Our algorithm automatically learns to detect lesions from thousands of MRI scans of patients. It can reliably detect lesions of different types, shapes and sizes, and even many of those lesions that were previously missed by radiologists.”

Co-senior author, Dr Sophie Adler (UCL Great Ormond Street Institute of Child Health) added: “We hope that this technology will help to identify epilepsy-causing abnormalities that are currently being missed. Ultimately it could enable more people with epilepsy to have potentially curative brain surgery.”

This study on FCD detection uses the largest MRI cohort of FCDs to date, meaning it is able to detect all types of FCD.

The MELD FCD classifier tool can be run on any patient with a suspicion of having an FCD who is over the age of 3 years and has an MRI scan.

The MELD project is supported by the Rosetrees Trust.

Study limitations

Different MRI scanners were used at the 22 hospitals involved in the study around the globe, which enables the algorithm to be more robust but might also affect algorithm sensitivity and specificity.

Hydrogen is gaining significant attention as an efficient way to store ‘green energy’ from renewables such as wind and solar. Compressed gas is the most common form of hydrogen storage, however it can also be stored in a liquid or solid state.

Dr Saidul Islam, from the University of Technology Sydney, said solid hydrogen storage, and in particular metal hydride, is attracting interest because it is safer, more compact, and lower cost than compressed gas or liquid, and it can reversibly absorb and release hydrogen.

“Metal hydride hydrogen storage technology is ideal for onsite hydrogen production from renewable electrolysis. It can store the hydrogen for extended periods and once needed, it can be converted as gas or a form of thermal or electric energy when converted through a fuel cell,” said Dr Islam.

“Applications include hydrogen compressors, rechargeable batteries, heat pumps and heat storage, isotope separation and hydrogen purification. It can also be used to store hydrogen in space, to be used in satellites and other ‘green’ space technology,” he said.

However, a problem with metal hydride for hydrogen energy storage has been its low thermal conductivity, which leads to slow charging and discharging times.

To address this the researchers developed a new method to improve solid-state hydrogen charging and discharging times. The study: Design optimization of a magnesium-based metal hydride hydrogen energy storage system, was recently published in the journal Scientific Reports.

First author Puchanee Larpruenrudee, a PhD candidate in the UTS School of Mechanical and Mechatronic Engineering, said faster heat removal from the solid fuel cell results in faster charging times.

“Several internal heat exchangers have been designed for use with metal hydride hydrogen storage. These include straight tubes, helical coil or spiral tubes, U-shape tubes, and fins. Using a helical coil significantly improves heat and mass transfer inside the storage.

“This is due to the secondary circulation and having more surface area for heat removal from the metal hydride powder to the cooling fluid. Our study further developed a helical coil to increase heat transfer performance.”

The researchers developed a semi-cylindrical coil as an internal heat exchanger, which significantly improved heat transfer performance. The hydrogen charging time was reduced by 59% when using the new semi-cylindrical coil compared to a traditional helical coil heat exchanger.

They are now working on the numerical simulation of the hydrogen desorption process, and continuing to improve absorption times. The semi-cylindrical coil heat exchanger will be further developed for this purpose.

Finally, the researchers aim to develop a new design for hydrogen energy storage, which will combine other types of heat exchangers. They hope to also work with industry partners to investigate real tank performance based on the new heat exchanger.

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