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Jul 31, 2022

Deep neural networks constrained by neural mass models improve electrophysiological source imaging of spatiotemporal brain dynamics

Posted by in categories: biotech/medical, neuroscience, robotics/AI

Many efforts have been made to image the spatiotemporal electrical activity of the brain with the purpose of mapping its function and dysfunction as well as aiding the management of brain disorders. Here, we propose a non-conventional deep learning–based source imaging framework (DeepSIF) that provides robust and precise spatiotemporal estimates of underlying brain dynamics from noninvasive high-density electroencephalography (EEG) recordings. DeepSIF employs synthetic training data generated by biophysical models capable of modeling mesoscale brain dynamics. The rich characteristics of underlying brain sources are embedded in the realistic training data and implicitly learned by DeepSIF networks, avoiding complications associated with explicitly formulating and tuning priors in an optimization problem, as often is the case in conventional source imaging approaches. The performance of DeepSIF is evaluated by 1) a series of numerical experiments, 2) imaging sensory and cognitive brain responses in a total of 20 healthy subjects from three public datasets, and 3) rigorously validating DeepSIF’s capability in identifying epileptogenic regions in a cohort of 20 drug-resistant epilepsy patients by comparing DeepSIF results with invasive measurements and surgical resection outcomes. DeepSIF demonstrates robust and excellent performance, producing results that are concordant with common neuroscience knowledge about sensory and cognitive information processing as well as clinical findings about the location and extent of the epileptogenic tissue and outperforming conventional source imaging methods. The DeepSIF method, as a data-driven imaging framework, enables efficient and effective high-resolution functional imaging of spatiotemporal brain dynamics, suggesting its wide applicability and value to neuroscience research and clinical applications.

Jul 31, 2022

Supplemental Vitamin D and Incident Fractures in Midlife and Older Adults

Posted by in categories: biotech/medical, sex

In an ancillary study of the Vitamin D and Omega-3 Trial (VITAL), we tested whether supplemental vitamin D3 would result in a lower risk of fractures than placebo. VITAL was a two-by-two factorial, randomized, controlled trial that investigated whether supplemental vitamin D3 (2000 IU per day), n−3 fatty acids (1 g per day), or both would prevent cancer and cardiovascular disease in men 50 years of age or older and women 55 years of age or older in the United States. Participants were not recruited on the basis of vitamin D deficiency, low bone mass, or osteoporosis. Incident fractures were reported by participants on annual questionnaires and adjudicated by centralized medical-record review. The primary end points were incident total, nonvertebral, and hip fractures. Proportional-hazards models were used to estimate the treatment effect in intention-to-treat analyses.

Among 25,871 participants (50.6% women [13,085 of 25,871] and 20.2% Black [5106 of 25,304]), we confirmed 1991 incident fractures in 1,551 participants over a median follow-up of 5.3 years. Supplemental vitamin D3, as compared with placebo, did not have a significant effect on total fractures (which occurred in 769 of 12,927 participants in the vitamin D group and in 782 of 12,944 participants in the placebo group; hazard ratio, 0.98; 95% confidence interval [CI], 0.89 to 1.08; P=0.70), nonvertebral fractures (hazard ratio, 0.97; 95% CI, 0.87 to 1.07; P=0.50), or hip fractures (hazard ratio, 1.01; 95% CI, 0.70 to 1.47; P=0.96). There was no modification of the treatment effect according to baseline characteristics, including age, sex, race or ethnic group, body-mass index, or serum 25-hydroxyvitamin D levels. There were no substantial between-group differences in adverse events as assessed in the parent trial.

Vitamin D3 supplementation did not result in a significantly lower risk of fractures than placebo among generally healthy midlife and older adults who were not selected for vitamin D deficiency, low bone mass, or osteoporosis. (Funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases; VITAL ClinicalTrials.gov number, NCT01704859.)

Jul 31, 2022

DeepMind AI Powers Major Scientific Breakthrough: AlphaFold Generates 3D View of the Protein Universe

Posted by in categories: alien life, robotics/AI, sustainability

AI-powered predictions of the three-dimensional structures of nearly all cataloged proteins known to science have been made by DeepMind and EMBL’s European Bioinformatics Institute (EMBL-EBI). The catalog is freely and openly available to the scientific community, via the AlphaFold Protein Structure Database.

The two organizations hope the expanded database will continue to increase our understanding of biology, helping countless more scientists in their work as they strive to tackle global challenges.

This major milestone marks the database being expanded by approximately 200 times. It has grown from nearly 1 million protein structures to over 200 million, and now covers almost every organism on Earth that has had its genome sequenced. Predicted structures for a wide range of species, including plants, bacteria, animals, and other organisms are now included in the expanded database. This opens up new avenues of research across the life sciences that will have an impact on global challenges, including sustainability, food insecurity, and neglected diseases.

Jul 31, 2022

Ex-SpaceX Engineer Builds Martian Nuclear Reactor To Tackle Earth’s Power Crisis

Posted by in categories: Elon Musk, nuclear energy, space travel, sustainability

Elon Musk has already shaped our world in several different ways, and the debate of whether they’re all beneficial to humanity is ongoing. But apart from putting electric vehicles on top of the automotive world’s agenda and making us dream about outer space travel, there is one somewhat unintentiona…

Jul 31, 2022

The consciousness of bees

Posted by in category: neuroscience

Experiments indicate that bees have surprisingly rich inner worlds.

Jul 31, 2022

Researchers turn discarded CDs into flexible and stretchable biosensors

Posted by in categories: chemistry, materials

The CD was initially soaked in 40 mL of acetone for 1.5 minutes, releasing the metal layer by breaking down the polycarbonate substrate. The metal from the CD was easily harvested with polyimide tape, which also serves as the substrate layer in the new device integration to improve the mechanical durability and robustness of the thin metal film.

“When you pick up your hair on your clothes with sticky tape, that is essentially the same mechanism,” said Assistant Professor Ahyeon Koh, who led the research. “We loosen the layer of metals from the CD and then pick up that metal layer with tape, so we just peel it off. That thin layer is then processed and flex ible.”

Researchers created the sensors utilizing a commercially available Cricut cutter, an off-the-shelf machine for crafters that generally cut designs from materials like paper, vinyl, card stock, and iron-on transfers. The flexible circuits then would be removed and stuck onto a person. The whole fabrication process was completed in 20–30 minutes, without releasing toxic chemicals or needing expensive equipment, and it costs about $1.50 per device.

Jul 31, 2022

SpaceX shares how it’s making Starlink satellite less bright

Posted by in categories: internet, satellites

SpaceX shared how it’s making its Starlink satellites less bright. The space exploration company published a document titled, Brightness Mitigation Best Practices for Satellite Operators that outlines how it’s working with the astronomy community to reduce light pollution.

New document from @SpaceX https://api.starlink.com/public-files/BrightnessMitigationBe…rators.pdf explaining what they have been doing to make their satellites less bright. I applaud SpaceX for their work on this (and for making the document public), while remaining concerned to see how bright the Gen2 Starlinks end up being.

— Jonathan McDowell (@planet4589) July 29, 2022

Jul 31, 2022

Parts of the moon have stable temperatures fit for humans, researchers find

Posted by in category: space

Researchers discovered that lunar pits and caves could provide stable temperatures around 63 degrees Fahrenheit, leading to new possibilities for experiments and life there.

Jul 31, 2022

In Experiment, AI Successfully Impersonates Famous Philosopher

Posted by in category: robotics/AI

It was difficult for people to guess whether philosophical responses came from the philosopher Daniel Dennett or the language generator GPT-3.

Jul 31, 2022

Development of solid-state electrolytes for sodium-ion battery–A short review

Posted by in categories: chemistry, nuclear energy, particle physics, space, sustainability

Nowadays, the development of renewable energy sources, such as wind, solar, and nuclear energy sources, has become imperative, due to the limited resource constraints of the traditional fossil fuels [1 ]. However, these renewable sources could not deliver a regular power supply as the sources are variable in time and diffuse in space. Thus, the focus has been shifted to the electrical energy storage to smooth the intermittency of the energy sources. Rechargeable battery has the ability to store chemical energy and convert it into electrical energy with high efficiency [ 2]. Lithium-ion battery (LIB), as one typical rechargeable electrochemical battery, has dominated the markets of portable electronic devices, electric vehicles, and hybrid electric vehicles in the past decades, due to its high output voltages, high energy densities, and long cycle life; even though the high cost and the shortage of lithium resources are inhibiting the application of LIB in large-scale energy storage [[3], [4], [5], [6], [7], [8], [9]].

Sodium-ion battery (SIB) is one promising alternative to LIB, with comparable performance to that of LIB, abundant sodium resources and low price of starting materials [[10], [11], [12], [13]]. As Na atom is heavier and larger than those of Li atom, the gravimetric and volumetric energy density of Na-ion battery are expected to not exceed those of the Li analogues [14]. However, energy density would not be considered as the critical issue in the field of large-scale grid support, for which the operating cost and the battery durability are the most important aspects [15,16].