Computers Math

Engineering researchers have invented an advanced brain-computer interface with a flexible and moldable backing and penetrating microneedles. Adding a flexible backing to this kind of brain-computer interface allows the device to more evenly conform to the brain’s complex curved surface and to more uniformly distribute the microneedles that pierce the cortex. The microneedles, which are 10 times thinner than the human hair, protrude from the flexible backing, penetrate the surface of the brain tissue without piercing surface venules, and record signals from nearby nerve cells evenly across a wide area of the cortex.
This novel brain-computer interface has thus far been tested in rodents. The details were published online on February 25 in the journal Advanced Functional Materials. This work is led by a team in the lab of electrical engineering professor Shadi Dayeh at the University of California San Diego, together with researchers at Boston University led by biomedical engineering professor Anna Devor.
This new brain-computer interface is on par with and outperforms the “Utah Array,” which is the existing gold standard for brain-computer interfaces with penetrating microneedles. The Utah Array has been demonstrated to help stroke victims and people with spinal cord injury. People with implanted Utah Arrays are able to use their thoughts to control robotic limbs and other devices in order to restore some everyday activities such as moving objects.
The backing of the new brain-computer interface is flexible, conformable, and reconfigurable, while the Utah Array has a hard and inflexible backing. The flexibility and conformability of the backing of the novel microneedle-array favors closer contact between the brain and the electrodes, which allows for better and more uniform recording of the brain-activity signals. Working with rodents as model species, the researchers have demonstrated stable broadband recordings producing robust signals for the duration of the implant which lasted 196 days.
In addition, the way the soft-backed brain-computer interfaces are manufactured allows for larger sensing surfaces, which means that a significantly larger area of the brain surface can be monitored simultaneously. In the Advanced Functional Materials paper, the researchers demonstrate that a penetrating microneedle array with 1,024 microneedles successfully recorded signals triggered by precise stimuli from the brains of rats. This represents ten times more microneedles and ten times the area of brain coverage, compared to current technologies.
Thinner and transparent backings
These soft-backed brain-computer interfaces are thinner and lighter than the traditional, glass backings of these kinds of brain-computer interfaces. The researchers note in their Advanced Functional Materials paper that light, flexible backings may reduce irritation of the brain tissue that contacts the arrays of sensors. More

As automated truck technology continues to be developed in the United States, there are still many questions about how the technology will be deployed and what its potential impacts will be on the long-haul trucking market.
A new study by researchers at the University of Michigan and Carnegie Mellon University assessed how and where automation might replace operator hours in long-haul trucking.
They found that up to 94% of operator hours may be impacted if automated trucking technology improves to operate in all weather conditions across the continental United States. Currently, automated trucking is being tested mainly in the Sun Belt.
“Our results suggest that the impacts of automation may not happen all at once. If automation is restricted to Sun Belt states (including Florida, Texas and Arizona) — because the technology may not initially work well in rough weather — about 10% of the operator hours will be affected,” said study co-author Parth Vaishnav, assistant professor of sustainable systems at the U-M School for Environment and Sustainability.
Using transportation data from the 2017 Commodity Flow Survey, which is produced by the U.S. Bureau of Transportation Statistics, U.S. Census Bureau and U.S. Department of Commerce, the study authors gathered information on trucking shipments and the operator hours used to fulfill those shipments.
In addition, they explored different automated trucking deployment scenarios, including deployment in southern, sunny states; deployment in spring and summer months (April 1 to Sept. 30); deployment for journeys more than 500 miles; and deployment across the United States. More

Solar-powered adsorption cooling systems (SACS) have gained traction as a renewable energy technology that could provide clean power for air conditioning and refrigeration while significantly reducing the load on the electric grid. But these systems lack energy efficiency.
In the Journal of Renewable and Sustainable Energy, by AIP Publishing, researchers from Anna University in India developed an optimizer tool to design, evaluate, and maximize the performance of different types of SACS under various operating scenarios. The tool was created using Visual Basic programming language that is easy to learn and enables rapid application development.
“Our user-friendly optimizer is a multifunctional tool capable of designing and analyzing a complete solar powered adsorption refrigeration system,” co-author Edwin Mohan said. “Our tool is capable of assessing different combinations of operational parameters to determine the settings that maximize system performance.”
SACS, which work by turning solar energy into heat, consists of a sorption bed, condenser, liquid storage tank, expansion valve, and evaporator. At night, water or another refrigerant is vaporized through the evaporator.
During daylight hours, heat obtained from the sun causes the vapor to travel through the condenser, where it is reliquefied to release latent heat. The liquid eventually returns to the evaporator to repeat the process.
One of the most important elements of SACS is the pairing of materials used in the adsorption process in which atoms or molecules of a substance (the adsorbate) adhere to the surface of a porous material (the adsorbent), like activated carbon and zeolite, to maximize the surface-to-volume ratio.
In their study, the researchers used their computational tool to test two adsorbent/adsorbate pairs: activated-carbon and methanol, and zeolite and water. The experiments were carried out over four days in a prototype SACS with a cooling capacity of 0.25 kilowatts. They found the activated-carbon-methanol combination achieved a higher coefficient of performance, but the zeolite-water adsorption system could operate at higher temperatures.
The optimizer tool predicted the proper material mass concentration ratios. The method calculated the cooling load, predicted maximal performance, and conducted the overall performance analysis of the cooling system.
Although the study focused on residential home cooling systems, the researchers said their optimizer tool could be extended to higher capacity systems.
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Materials provided by American Institute of Physics. Note: Content may be edited for style and length. More

For the first time, Australian researchers have reverse engineered the visual systems of hoverflies to detect drones’ acoustic signatures from almost four kilometres away.
Autonomous systems experts from the University of South Australia, Flinders University and defence company Midspar Systems say that trials using bio-inspired signal processing techniques show up to a 50 per cent better detection rate than existing methods.
The findings, which could help combat the growing global threat posed by IED-carrying drones, including in Ukraine, have been reported in The Journal of the Acoustical Society of America.
UniSA Professor of Autonomous Systems, Anthony Finn, says that insect vision systems have been mapped for some time now to improve camera-based detections, but this is the first time that bio-vision has been applied to acoustic data.
“Bio-vision processing has been shown to greatly increase the detection range of drones in both visual and infrared data. However, we have now shown we can pick up clear and crisp acoustic signatures of drones, including very small and quiet ones, using an algorithm based on the hoverfly’s visual system,” Prof Finn says.
The hoverfly’s superior visual and tracking skills have been successfully modelled to detect drones in busy, complex and obscure landscapes, both for civilian and military purposes. More

Every year, hundreds of thousands of scientists spend tens of billions of dollars to organize and attend conferences.
Are scientific conferences truly worth this time and money?
The answer is yes, according to a new Northwestern University study. Scientists who interact with others during assigned sessions at conferences are more likely to form productive collaborations than scientists who do not, researchers found. And the kicker? It doesn’t matter whether the conference is in person or virtual.
“Scientific conferences are a very expensive industry,” said Northwestern’s Emma Zajdela, the study’s first author. “People often talk about whether or not we should rethink conferences. Our results suggest that the way organizers design conferences can have a direct effect on which scientific collaborations are formed and, by extension, on the direction of scientific inquiry.”
Zajdela will present the study’s results at 9:36 a.m. CDT on Thursday, March 17 at the American Physical Society (APS) March Meeting in Chicago. A pre-print of the study is now available online.
A National Science Foundation Graduate Research Fellow, Zajdela is a Ph.D. candidate in Northwestern’s McCormick School of Engineering. Daniel Abrams, a professor of engineering sciences and applied mathematics at McCormick, is the paper’s senior author and Zajdela’s adviser. More

Researchers at Duke University have demonstrated the first attack strategy that can fool industry-standard autonomous vehicle sensors into believing nearby objects are closer (or further) than they appear without being detected.
The research suggests that adding optical 3D capabilities or the ability to share data with nearby cars may be necessary to fully protect autonomous cars from attacks.
The results will be presented Aug. 10-12 at the 2022 USENIX Security Symposium.
One of the biggest challenges researchers developing autonomous driving systems have to worry about is protecting against attacks. A common strategy to secure safety is to check data from separate instruments against one another to make sure their measurements make sense together.
The most common locating technology used by today’s autonomous car companies combines 2D data from cameras and 3D data from LiDAR, which is essentially laser-based radar. This combination has proven very robust against a wide range of attacks that attempt to fool the visual system into seeing the world incorrectly.
At least, until now. More

A Scripps Research team developed a smartphone app that can calculate users’ genetic risk for coronary artery disease (CAD) — and found that users at high risk sought out appropriate medication after using the app.
In the study, which appears in npj Digital Medicine in March 2022, the researchers detailed how their app called MyGeneRank inputs participating individuals’ genetic information from the 23andMe genetic testing company and outputs a CAD risk score based on the DNA data. Of the 721 participants who provided complete information, those with high-risk scores were much more likely to start using statins or other cholesterol-lowering therapies, compared to those with low-risk scores.
“We saw about twice the rate of statin initiation in the high genetic risk group vs the low genetic risk group, which indicates that strategies like this could make a big contribution to public health — heart disease being the largest cause of death globally,” says study senior author Ali Torkamani, PhD, professor and director of Genomics and Genome Informatics at the Scripps Research Translational Institute.
According to the U.S. Centers for Disease Control and Prevention, about 18 million American adults have CAD, the most common form of heart disease, which features the hardening and narrowing of arteries feeding the heart muscle. More than 300,000 Americans die of resulting heart attacks every year.
Statins such as atorvastatin and simvastatin, as well as other, non-statin drugs that reduce bloodstream levels of cholesterol and other fat-related molecules called lipids, are now widely used, and have helped reduce the annual death rate from CAD over the past two decades. But researchers estimate that in the US nearly half of men and about 10 percent of women between 45 and 65 years old are at least at intermediate risk of CAD — yet only about a third of these individuals take lipid-lowering drugs.
Calculating CAD risk scores and communicating that information via smartphone apps is now being considered as a highly scalable method for nudging more at-risk people to seek medical advice and get lipid-lowering medications when appropriate, thereby lowering the incidence of CAD and heart-attacks. More

Experimental physicists have succeeded for the first time in controlling protected quantum states — so-called dark states — in superconducting quantum bits. The entangled states are 500 times more robust and could be used, for example, in quantum simulations. The method could also be used on other technological platforms.
In Gerhard Kirchmair’s laboratory at the Institute of Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences in Innsbruck, Austria, superconducting quantum bits are coupled to waveguides. When several of these quantum bits are incorporated into the waveguide, they interact with each other, resulting in so-called dark states. “These are entangled quantum states that are completely decoupled from the outside world,” explains Max Zanner, first author of the paper. “They are invisible, so to speak, which is why they are called dark states.” These states are of interest for quantum simulations or the processing of quantum information — corresponding proposals have been made several times in recent years. To date, however, it has not been possible to control and manipulate these dark states appropriately without breaking their invisibility. Now, the team led by Gerhard Kirchmair has developed a system with which the dark states of superconducting circuits in a microwave waveguide can be manipulated from the outside.
Expandable as desired
“Until now, the problem has always been, how to control dark states that are completely decoupled from the environment,” says Gerhard Kirchmair, who is also a professor of experimental physics at the University of Innsbruck. “With a trick, we have now succeeded in finding access to these dark states.” His team built four superconducting quantum bits into a microwave waveguide and attached control lines via two lateral inlets. Using microwave radiation via these wires, the dark states can be manipulated. Together, the four superconducting circuits form a robust quantum bit with a storage time about 500 times longer than that of the individual circuits. Multiple dark states exist simultaneously in this quantum bit, which can be used for quantum simulation and quantum information processing. “In principle, this system can be extended arbitrarily,” says Matti Silveri from the Nano and Molecular Systems Research Unit at the University of Oulu, Finland.
The successful experiment forms the starting point for further investigations of dark states and their possible applications. For the time being, these are mainly in the field of fundamental research, where there are still many open questions regarding the properties of such quantum systems. The concept developed by the Innsbruck physicists to control dark states can in principle be implemented not only with superconducting quantum bits, but also on other technological platforms. “However, the circuits we use, which function like artificial atoms, have advantages over real atoms, which are much more difficult to couple strongly to a waveguide,” Gerhard Kirchmair emphasizes.
Nature Physics published the results in its current issue. The research was financially supported by the Austrian Science Fund FWF, the Academy of Finland, and the European Union, among others. Maximilian Zanner and Christian Schneider are members of the FWF Doctoral Program Atoms, Light and Molecules (DK-ALM) at the University of Innsbruck.
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Materials provided by University of Innsbruck. Note: Content may be edited for style and length. More