Tech

Skoltech researchers and their colleagues from RAS Institute for Physics of Microstructures, Lobachevsky State University of Nizhny Novgorod, ITMO University, Lomonosov Moscow State University, and A.M. Prokhorov General Physics Institute have found a way to increase photoluminescence in silicon, the notoriously poor emitter and absorber of photons at the heart of all modern electronics. This discovery may pave the way to photonic integrated circuits, boosting their performance. The paper was published in the journal Laser and Photonics Reviews.

"Natural selection" in semiconductor technology over almost 80 years has led to silicon emerging as the predominant material for chips. Most digital microcircuits are created using CMOS technology (CMOS), which stands for complementary metal-oxide-semiconductor. Yet manufacturers have hit a wall on the way to increasing their performance even further: heat release due to high density of elements in CMOS circuits.

One potential workaround is reducing heat generation by switching from metallic connections between elements in microcircuits to optical ones: unlike electrons in conductors, photons can travel giant distances in wavegiudes with minimal heat losses.

"The transition to CMOS-compatible photonic integrated circuits will also make it possible to significantly increase the information transfer rate within a chip and between individual chips in modern computers, making them faster. Unfortunately, silicon itself weakly interacts with light: it is a poor emitter and a poor absorber of photons. Therefore, taming silicon to interact with light effectively is an essential task," Sergey Dyakov, senior researcher at Skoltech and the first author of the paper, says.

Dyakov and his colleagues have managed to enhance silicon-based photoluminescence using germanium quantum dots and a specially designed photonic crystal. They used a resonator based on bound states in the continuum, an idea borrowed from quantum mechanics: these resonators create effective confinement of light inside them since the symmetry of the electromagnetic field inside the resonator does not correspond to the symmetry of the electromagnetic waves of the surrounding space.

They also chose germanium nanoislands as a source of luminescence, which can be embedded into the desired place on a silicon chip. "The use of bound states in the continuum increased luminescence intensity by more than a hundred times," Dyakov says, noting that it can lead us to CMOS-compatible photonic integrated circuits.

"The results open up new possibilities for creating efficient radiation sources based on silicon, built into the circuits of modern microelectronics with optical signal processing. There are currently lots of groups working on creating light-emitting diodes based on such structures and the principles of their coupling with other elements on an optoelectronic chip," Professor Nikolay Gippius, head of Nanophotonics Theory group at the Center of Photonics and Quantum Materials at Skoltech, says.

Smokers needed their blocked arteries fixed nearly a decade earlier than non-smokers, and patients with obesity underwent these procedures four years earlier than non-obese patients, according to a new statewide study.

The research included patients without a history of heart attack who were treated at hospitals across Michigan participating in BMC2, the Blue Cross Blue Shield of Michigan Cardiovascular Consortium. The patients had undergone angioplasty and/or stenting to widen or unblock their coronary arteries and restore blood flow. Almost all of them had at least one traditional risk factor, including smoking, obesity, high blood pressure, high cholesterol and diabetes. Most had three or more.

Additionally, women generally had their first procedure at a later age than men. Over the past decade, among patients undergoing their first angioplasty or stent procedure, the rates of obesity and diabetes have increased, while smoking and high cholesterol have decreased.

"Smoking is a completely preventable risk factor," said senior author Devraj Sukul, M.D., M.Sc., an interventional cardiologist and a clinical lecturer at the University of Michigan Health Frankel Cardiovascular Center. "If we direct additional efforts at preventing smoking and obesity we could significantly delay the onset of heart disease and the need for angioplasty and stenting."

Smoking cessation is a growing focus of the Michigan Collaborative Quality Initiatives, of which BMC2 is a member.

"In Michigan, we will work to help every smoker quit at the time of cardiac care because it is an unmatched teachable moment for patients," said Michael Englesbe, M.D., a surgeon and professor at Michigan Medicine who serves as portfolio medical director for the Collaborative Quality Initiatives.

Sukul also serves as associate director of BMC2's work in percutaneous coronary intervention.

DARIEN, IL - Preliminary results of a new study show that a wearable electroencephalogram device that gathers data from the ear measures sleep as reliably as traditional EEG electrodes attached to the scalp.

Comparing the distributions of intra-individual neural signature similarities for ear-EEG and scalp-EEG across four nights, results show that the observed mean difference between distributions was statistically significant, in favor of a more stable ear-EEG signature. Further analysis found that an individual's neural signature recorded by the ear-EEG for four nights followed by continued monitoring for 12 nights was stable over time, demonstrating its ability as a personalized signature with a 90.1% classification accuracy.

"The most surprising results from the study were the stability of the ear-EEG neural characteristic over time and the systematic variation across individuals," said lead researcher Martin Hemmsen, who has a doctorate in biomedical engineering and is a lead sleep and cognition researcher at T&W Engineering in Denmark.

The researchers initiated a two phased in-home study, monitoring 20 participants for four nights in the first phase. Each participant's sleep was evaluated using both an ear-centered dry-electrode EEG recorder and partial polysomnography comprising EEG, electrooculography, and electromyography monitoring. In the second phase, 10 participants wore only the ear-EEG device for an additional 12 nights. The researchers analyzed the intra- and inter-individual similarity of the power spectra of non-REM stage 2 sleep recorded by ear-EEG and scalp-EEG.

According to the authors, changes in personalized neural signatures have been associated with biomarkers of Alzheimer's disease, meaning that the ear-EEG may prove to be useful in early detection of neural degeneration.

"The results are important because the study shows that simple, wearable EEG devices for home and unassisted use can monitor individual characteristics reliably," said Hemmsen. "Future studies will explore if monitoring these individual characteristics over time can be used as a biomarker for early detection of neurological complications."

The study was conducted by researchers from both T&W Engineering and Center for Ear-EEG headed by Prof. Preben Kidmose at Aarhus University. The center was established in January 2020 with seed funding from the William Demant Foundation and T&W Engineering. The research was conducted as part of the Ear-EEG Sleep Monitor (EESM) research consortium (T&W Engineering, Preben Kidmose from Aarhus University; Troels Kjær, MD, from Zealand University Hospital; Marit Otto, PhD, MD, from Aarhus University).

The research abstract was published recently in an online supplement of the journal Sleep and will be presented as a poster beginning June 9 during Virtual SLEEP 2021. SLEEP is the annual meeting of the Associated Professional Sleep Societies, a joint venture of the American Academy of Sleep Medicine and the Sleep Research Society.

An international research team led by members from the Technical University of Munich, the Deutsches Museum, Munich, and the Swedish Linköping University has developed a method to manufacture two-dimensional polymers with the thickness of a single molecule. The polymers are formed on a surface by the action of light. The discovery paves the way to new ultrathin and functional materials.

The quest for new two-dimensional materials has rapidly intensified after the discovery of graphene - a supermaterial whose excellent properties include high conductivity and strength, making it incredibly versatile.

Two main approaches are used to create ultrathin materials. In the first, a continuous layer of molecules or atoms is "peeled off" from the bulk of the material. Graphene is an example of such a material.

The other approach, in contrast, involves the construction of the material molecule-by-molecule by producing bonds between the molecules in various ways. The problem is that the materials are often small, fragile and contain many defects. This limits the potential areas of application.

Self organization and photopolymerisation produce new 2D-material

An international research team with members from the Technical University of Munich, the Deutsches Museum and Linköping University, among others, has now developed a new method to manufacture two-dimensional polymers. The discovery makes it possible to develop new ultrathin functional materials with highly defined and regular crystalline structures.

The manufacture, or polymerisation, of the material takes place in two steps. The researchers use a molecule known as "fantrip". "Fantrip" is a contraction of "fluorinated anthracene triptycene". This molecule is a merger of two different hydrocarbons - anthracene and triptycene. The specific properties of fantrip cause the molecules to spontaneously arrange themselves into a pattern when they are placed onto a graphite surface covered with an alkane. This process is known as "self-organization".

The next step is the photopolymerisation itself, when the pattern is to be fixed with the aid of light. The molecules are illuminated by a violet laser that excites the electrons in the outermost electron shell. This causes strong and durable covalent bonds to form between the molecules.

The result is a porous two-dimensional polymer, half a nanometre thick, consisting of several hundred thousand molecules identically linked, in other words, a material with nearly perfect order, right down to the atomic level.

Simulations confirm the assigned structures

Since the photopolymerisation is carried out on a surface of solid graphite, it is possible to follow the process on the molecular scale using scanning tunnelling microscopy. This shows the newly formed bonds in a persistent network. In order to confirm the structure assignment, the research group led by Jonas Björk has simulated the appearance of the molecular networks under the microscope at different stages of the reaction.

Jonas Björk is assistant professor in the Materials Design Division at the Department of Physics, Chemistry and Biology at Linköping University. He has used high-performance computing resources at the National Supercomputer Centre in Linköping to validate the experiments and understand the key factors that make the method successful.

"We see that the simulations agree well with reality down to the tiniest detail, and we can also understand why our specific system gives such useful results. The next step of the research will be to see whether the method can be used to link other molecules for new two-dimensional and functional materials. By improving the method, we will also be able to control and tailor the type of ultrathin materials we aim to manufacture", says Jonas Björk.

Fixing self-organized molecules with light

"Creating covalent bonds between molecules requires a lot of energy. The most common way of supplying energy is to raise the temperature, but this also causes the molecules to start moving. So it won't work with self-organized molecules, since the pattern would blurr. Using light to create covalent bonds preserves the pattern and fixes it precisely as we want it", says Markus Lackinger, research group leader at the Deutsches Museum and Technical University of Munich.

The polymerisation takes place in a vacuum, which ensures that the material is not contaminated. However, the final two-dimensional polymer film is also stable under atmospheric conditions, which is an advantage for future applications. Markus Lackinger believes that the material will find many conceivable applications.

"The most obvious application is to use the material as filter or membrane, but applications that we have no idea of at the moment in entirely different contexts may appear on the horizon, also by chance. This is why basic research is so exciting", says Markus Lackinger.

WASHINGTON -- In a new study, researchers demonstrate an automated, easy-to-operate quantum key distribution (QKD) system using the fiber network in the city of Padua, Italy. The field test represents an important step toward implementing this highly secure quantum communication technology using the type of communication networks already in place in many regions around the world.

QKD offers impenetrable encryption for data communication because it uses the quantum properties of light to generate secure random keys for encrypting and decrypting data.

"QKD can be useful in any situation where security is paramount because it offers unconditional security for the key exchange process," said Marco Avesani from Università degli Studi di Padova in Italy, co-first author of the new study with Luca Calderaro and Giulio Foletto. "It can be used to encrypt and authenticate health data sent between hospitals or money transfers among banks, for example."

In The Optical Society (OSA) journal Optics Letters, researchers led by Paolo Villoresi and Giuseppe Vallone report that their simple system is stable over time and can generate quantum-secure cryptographic keys at sustained rates over a standard telecommunications infrastructure.

"QKD systems usually require a complex stabilization system and additional dedicated synchronization hardware," said Avesani. "We developed a complete QKD system that can be
directly interfaced with standard telecommunications equipment and doesn't require additional hardware for synchronization. The system fits easily into the rack enclosures commonly found in server rooms."

Designing an easy-to-use system

To produce the quantum states required by QKD, the researchers developed a new encoder for manipulating the polarization of single photons. The encoder, which the researchers call iPOGNAC, provides a fixed and stable polarization reference that doesn't require frequent recalibration. This feature is also advantageous for free-space and satellite quantum communication, where recalibrations are hard to perform.

"Because of the technology we developed, the source was ready to produce quantum states when we moved our system from the lab to the location of the field trial," said Calderaro. "We didn't have to perform the slow, and often prone-to-failure, alignment procedure required for most QKD systems."

The researchers also developed a new synchronization algorithm, which they call

Qubit4Sync, to synchronize the machines of the two QKD users. Rather than using dedicated additional hardware and an added frequency channel for synchronization, the new system uses software and the same optical signals being used for QKD. This makes the system smaller, cheaper, and easier to integrate into an existing optical network.

To test the new system, the researchers brought their two QKD terminals to two university buildings roughly 3.4 km apart in different sections of Padua. They connected the systems to two underground optical fibers that are part of the university's communication network. These fibers supported the quantum channel carrying qubits and the classical channel needed to transfer ancillary information.

A quantum-secured video call

"The field trial was successful," said Foletto. "We showed that our simple system can produce secret keys at speeds of kilobits per second and that it works outside of the laboratory with little human intervention. It was also easy and quick to install."

In a public demonstration, the researchers used their setup to enable a quantum-secured video call between the Rector of the University of Padua and the Director of the Mathematics Department. The researchers note that the system's performance is comparable to other commercial QKD systems in terms of secret key generation rate while also having fewer components and being easier to integrate into an existing fiber network.

They are working to reduce the size of the detection apparatus and to make the system more robust to noise from other light traveling in the same fiber. The effort to develop a complete and autonomous QKD system led to the creation of a spin-off company called ThinkQuantum s.r.l, which is working to commercialize this technology.

In the first three quarters of 2020, the COVID-19 pandemic caused a 30% fall in electronic and electrical equipment sales in low- and middle-income countries but only a 5% decline in high-income countries, highlighting and intensifying the digital divide between north and south, according to a new UN report.

Worldwide, sales of heavy electric appliances like refrigerators, washing machines and ovens fell the hardest -- 6-8% -- while small IT and telecommunications equipment decreased by only 1.4%. Within the latter category, sales of laptops, cell phones and gaming equipment rose in high-income countries and on a global basis, but fell in low- and middle-income countries.

The new report, by UN e-waste researchers, predicts an overall 4.9 million metric tonne (Mt) fall in future 2020 sales-related e-waste, about 6.4% less than a "business as usual" scenario.

"The Impact of the COVID-19 Pandemic on E-waste in the First Three Quarters of 2020," is published by the UN University's Sustainable Cycles Programme (SCYCLE), Bonn, and UNITAR, the United Nations' Institute for Training and Research, which recently established presence in Bonn.

The global-level results run contrary to early expectations, says Kees Balde, a UNU Senior Programme Officer, who co-authored the report with UNU SCYCLE and UNITAR colleague Ruediger Kuehr.

Home offices and schooling, online hang-outs and shopping, movie streaming and other activities driven higher by COVID-19 lockdowns had many experts predicting a sizeable increase in electrical and electronic equipment consumption, as well as an increase in e-waste disposal as people went house-cleaning and shopping to replace near-broken electronic equipment.

Worldwide, however, all major categories of electronic and electrical equipment - screens and monitors, large equipment, temperature exchange equipment, small equipment, and lamps - decreased by 6-8%.

By weight, the largest decrease in consumption was in the large equipment category, down by 1.7 Mt, followed by small equipment and lamps.

Impacts were largest in 2020's first and second quarters. Consumption rebounded in the third quarter in high-income countries, though not in low- and middle-income countries.

"The so-called digital divide is increasing," says Dr. Kuehr. "The ability to adapt to digitisation and earn a living or simply to own and benefit from electronics is decreasing in some parts of the world. COVID-19 also revealed a digital divide in high-come countries, where many poor are left behind."

A small silver lining is the reduction of e-waste flows, though likely temporary, he notes, in regions where e-waste mismanagement leads to large environmental and health damage.

The report urges that nations use this breathing space to improve e-waste management.

Dr. Balde; adds that COVID-19 has accentuated global inequality in other ways, causing half a billion people to be under-employed or out of work, with women twice as detrimentally-affected as men.

And workers in low income countries suffer most, losing 23% of their working hours and causing social disasters, as people fall into debt, skip meals, and keep their children home from school.

By region: Electronic and electrical equipment consumption, first three quarters of 2020

Northern Africa and Western Asia

In four countries with complete datasets for analysis (Armenia, Israel, Egypt, and Azerbaijan), an upward trend in consumption was observed, with minor fluctuations, from 2018 to 2019. All three quarters of 2020 showed a decline compared to previous quarters and to the same quarters a year earlier.

Sub-Saharan Africa

In three with complete datasets for analysis (South Africa, Mauritius, and Zambia) a fluctuating but upward trend in consumption occurred from 2018 to 2019. All three quarters of 2020 showed a decline, especially quarter 2, when the consumption was roughly 40% lower. The third quarter of 2020 showed an increase compared to the previous quarter, but below pre-COVID-19 levels.

Eastern and Southeast Asia

Five countries and Hong Kong had complete datasets for analysis (China, Hong Kong SAR, Japan, Maldives, India, and Pakistan), which showed a mildly fluctuating but upward trend in consumption from 2018 until the third quarter of 2019. From the fourth quarter of 2019 through the first two quarters of 2020 consumption decreased while the third quarter of 2020 showed an increase.

Central Asia

Only one country, Kyrgyzstan, had complete datasets for analysis and they showed a fluctuating but upward trend in consumption in 2018 and 2019, then a decrease in the first three quarters of 2020. The third quarter of 2020 was higher than quarter two, but not to the levels of pre-COVID-19 times.

Europe and North America

These regions had the best data coverage and the analysis included 22 countries of EU-27, Switzerland, Serbia, Norway, Canada, TFYR of Macedonia, United Kingdom, the United States, Belarus, and Iceland. The data showed a mildly fluctuating but upward trend in consumption in 2018 and 2019 then a decrease in the first two quarters of 2020. Consumption rose in the third quarter of 2020 -- higher than the second quarter and even higher than the third quarter of 2019. However, consumption in the first three quarters together did not reach pre-COVID-19 levels.

Australia and New Zealand

Consumption fluctuated in 2018 and 2019, with peaks in the fourth quarters and a slight decrease from 2018 to 2019 and decreases in the first two quarters of 2020 compared to the previous years. The third quarter of 2020 was remarkably higher than the second quarter. Overall, the increase in the third quarter is larger than the declines compared to the "business as usual" scenario, bringing the consumption levels of the first three quarters of 2020 back to those of 2018.

Latin America and the Caribbean

The study included data from four countries, Belize, El Salvador, Mexico, Antigua and Barbuda, which showed consumption fluctuating from 2018 through 2019, then decreasing consumption in the first two quarters of 2020 compared to the previous years. Consumption in 2020's third quarter was higher than the second, but did not reach pre-COVID-19 levels.

The pandemic's effect on e-waste involved was estimated by using monthly trade statistics on a representative sample of all e-waste categories from January 2018 to October 2020 in 50 countries. The results were extrapolated to all electronic products and compared against a "business as usual" scenario, based on the monthly data from 2018 and 2019, and corrected for seasonal fluctuations.

DALLAS, June 9, 2021 -- Many adults with a history of cardiovascular disease (CVD) continue to smoke cigarettes and/or use other tobacco products, despite knowing it increases their risk of having another cardiovascular event, according to new research published today in the Journal of the American Heart Association, an open access journal of the American Heart Association.

To understand how many adults with CVD continue to use tobacco products, investigators reviewed survey responses from the large, national Population Assessment of Tobacco and Health Study (PATH) to compare tobacco use rates over time. The participants of the current study included 2,615 adults (ages 18 or older) with a self-reported history of heart attack, heart failure, stroke or other heart disease, who completed four surveys over a course of four to five years.

The first survey occurred from 2013-2014, and the last one from 2016-2018. When the study began, nearly half of the study participants were women (48.5%); from self-identified responses 77% were white adults, 10.5% were Black adults, 8% were Hispanic adults and the remainder were multi-racial or other. In 2013 to 2014, nearly one-third of study participants (28.9%) reported using tobacco. This percentage translates to approximately 6 million U.S. adults who use tobacco despite a history of CVD.

Among the tobacco products used by study participants:

Cigarettes were the most common form of tobacco product used (82.8%), followed by any types of cigars (23.7%) and e-cigarettes (23.3%). Many participants used more than one type of tobacco product.

E-cigarette use without concurrent cigarette use among participants with CVD was uncommon (1.1%).

Use of smokeless tobacco products was reported by 8.2% of participants.

Use of other tobacco products was uncommon: pipe=3.7%; hookah=3.0%; snus (a Swedish, smokeless tobacco product)=1.2%; and dissolvable tobacco=0.3%.

In the final survey four to five years later, fewer than a quarter of smokers with CVD had quit using tobacco. Participation in a formal smoking cessation program dwindled from 10% of respondents during the second wave of the survey to approximately 2% by the end of the study.

"At the conclusion of our study, we were surprised that so few cigarette users with cardiovascular disease were part of a formal smoking-cessation program," said study co-lead author Cristian Zamora, M.D., FAHA, a third-year internal medicine resident at Jacobi Medical Center at Albert Einstein College of Medicine in the Bronx, New York. "It was also concerning that despite the well-documented benefits of stopping tobacco use after a CVD diagnosis, few people had stopped smoking over the course of the five-year study."

Among the other notable findings:

Most of the study participants with CVD (95.9%) reported knowing or believing that smoking can cause heart disease in smokers.

A significant proportion of the study participants (40.2%) said they believed e-cigarettes were less harmful than combustible cigarettes.

E-cigarette use varied based upon the general perception of harmfulness of using e-cigarettes compared to smoking cigarettes.

The prevalence of e-cigarette use and dual-use (smoking both combustible cigarettes and e-cigarettes) was higher among those participants who said they believed e-cigarettes are less harmful than cigarettes, compared to those who believed e-cigarettes are more harmful than cigarettes.

Dual use of cigarettes and e-cigarettes was more common among study participants than use of e-cigarettes alone.

"In the United States, heart disease is the leading cause of death, resulting in more than 365,000 deaths in 2018. A major risk factor for cardiovascular disease, including heart events and stroke, is smoking," said Rose Marie Robertson, M.D., FAHA, deputy chief science and medical officer of the American Heart Association, who was not involved with this study but serves as the co-director of the Association's Tobacco Center of Regulatory Science, which provided support for the study. "Fortunately, research clearly shows that quitting smoking can help prevent heart disease, even among people who have had it in the past. The findings of this new study are disturbing, although perhaps not surprising. These results indicate that critical public policies and interventions are needed to address this preventable, leading cause of death and disability not just in the U.S. but around the world."

Trends for tobacco use varied by gender, age, race/ethnicity and other socioeconomic characteristics of study participants:

Among adults with CVD, use of any tobacco product was associated with younger age.

Men were more likely than women to use any tobacco product except for e-cigarettes.

Women were 70% more likely than men to use e-cigarettes.

Hispanic participants were 60% less likely than white participants and 50% less likely than Black participants to use any tobacco product.

Lower levels of household income were associated with a higher likelihood of using any tobacco product.

Participants living below the poverty line (annual income of $23,550 in 2013 and $25,100 in 2018 for a family or household of four living in one of the 48 contiguous states or the District of Columbia), were twice as likely to report using any tobacco product compared to those living at twice the poverty level or above.

There were no significant differences in use of any tobacco product among adults with CVD across regions in the U.S.

"Our findings support the need for a stronger commitment from a multidisciplinary team, including the primary care professional, social worker, psychologist and cardiologist, to provide smoking-cessation therapies and counseling to people with cardiovascular disease," Zamora said. "Health care reforms and public health policies should improve the availability of tobacco-cessation programs and tools for high-risk populations."

The study has several limitations. The self-reporting of the participants' past heart disease and tobacco use could be inaccurate. Another limitation is that relatively few adults reported smoking e-cigarettes, so the relationship between past heart disease and e-cigarette use remains unclear.

The field of ultrafast nonlinear photonics has now become the focus of numerous studies, as it enables a host of applications in advanced on-chip spectroscopy and information processing. The latter in particular requires a strongly intensity-dependent optical refractive index that can modulate optical pulses faster than even picosecond timescales and on sub-millimeter scales suitable for integrated photonics.

Despite the tremendous progress made in this field, there is currently no platform providing such features for the ultraviolet (UV) spectral range, which is where broadband spectra generated by nonlinear modulation can be used for new on-chip ultrafast chemical and biochemical spectroscopy devices.

Now, an international team of scientists including EPFL have achieved giant nonlinearity of UV hybrid light-matter states ("exciton-polaritons") up to room temperature in a waveguide made of AlInGaN, a wide bandgap semiconductor material behind the solid-state lighting technology (e.g. white LEDs) and blue laser diodes.

Published in Nature Communications, the study is a collaboration between the University of Sheffield, ITMO Saint Petersburg, Chalmers University of Technology, the University of Iceland, and the LASPE at EPFL's Institute of Physics of the School of Basic Sciences.

The scientists used a compact 100 ?m-long device, to measure an ultrafast nonlinear spectral broadening of UV pulses with a nonlinearity 1000 times larger than that observed in common UV nonlinear materials, which is comparable to non-UV polariton devices.

Using AlInGaN is a significant step toward a new generation of integrated UV nonlinear light sources for advanced spectroscopy and measurement. "The AlInGaN system is a highly robust and mature semiconductor platform that shows strong excitonic optical transitions up to room temperature in the UV spectral range," says EPFL's Raphaël Butté, who worked on the study.

In a Journal of Neuroimaging analysis of data obtained from 193 patients with COVID-19 who had brain and/or spine imaging and a lumbar puncture because of neurologic symptoms, investigators found that imaging results were related to the presence of SARS-CoV-2 in the cerebrospinal fluid.

The results were called central nervous system hyperintense lesions and leptomeningeal enhancement. Ten percent of patients with hyperintense lesions in the brain/spine had a positive PCR test result for SARS-CoV-2 in the cerebrospinal fluid, compared with no patients without hyperintense lesions in the brain/spine. Twenty-five percent of patients with leptomeningeal enhancement had a positive PCR test result for SARS-CoV-2 in the cerebrospinal fluid, compared with 5% of patients without leptomeningeal enhancement.

"Understanding the relationship between imaging and cerebrospinal fluid findings can improve understanding of neurological symptoms in patients with COVID-19. Although hyperintense lesions in the brain/spine and leptomeningeal enhancement are associated with the presence of SARS-CoV-2 in the cerebrospinal fluid, it is important to recognize that a positive SARS-CoV-2 PCR in the cerebrospinal fluid is uncommon. These imaging findings are predominantly the result of inflammation, hypoxia, or ischemia, rather than infection, of the central nervous system," said lead author Ariane Lewis, MD, of NYU Langone Medical Center.

Oncotarget published "Differential expression of Vitamin D binding protein in thyroid cancer health disparities" which reported that thyroid cancer incidence, recurrence, and death rates are higher among Filipino Americans than European Americans.

In this study, the authors determined the correlation between differential DBP expression in tumor tissues and cancer staging in Filipino Americans versus European Americans.

The majority of Filipino Americans presented with advanced tumor staging. In contrast, European Americans showed early staging and very few advanced tumors.

On the contrary, in the tumor tissues derived from European Americans, moderate to strong DBP staining was detected and correlated to early staging. When downregulation of the DBP gene in papillary thyroid cancer cell lines was observed, tumor proliferation and migration were enhanced.

The Oncotarget Authors determined a differential expression of an essential biological molecule is linked to cancer staging in thyroid cancer health disparities in two ethnicities.

Dr. Salma Khan from The Loma Linda University School of Medicine said, "Thyroid cancer is one of the most prevalent endocrine cancers."

"Thyroid cancer is one of the most prevalent endocrine cancers."

They identified a highly polymorphic protein, called vitamin D binding protein that could play an important role in thyroid cancer progression in ethnically predisposed group.

Although DBP has both vitamin D-dependent/independent roles in cancer development, vitamin D-dependent DBP functions in cancer are well studied with inconclusive results.

Therefore, they tested whether DBP has the ">vitamin D-independent correlations/functions to thyroid cancer oncogenesis.

Although DBP is an essential protein with multifunctional properties, very few studies are available on its contribution to thyroid cancer oncogenesis.

In the present study, they determined the differential expression of DBP protein in the thyroid cancer tissues and correlated it to cancer staging in Filipino Americans compared to European Americans.

The Khan Research Team concluded in their Oncotarget Research Output, "we demonstrate that the presence or absence of DBP inversely correlates to thyroid cancer staging in two ethnicities. We report that most Filipino Americans presented with advanced thyroid cancer and showed low to no DBP expression. In contrast, European Americans with early stage PTC, showed a moderate to strong DBP expression, supporting the protective roles of DBP in the tumor microenvironment, independent of vitamin D. Our in vitro study details the functional consequences of loss-of/gain-in-DBP-function in thyroid cancer oncogenesis. We conclude that the gain/loss of DBP may stimulate immune-modulated signaling pathways in thyroid cancer health disparities, which awaits further investigation."

The oxide dispersion strengthened copper alloy (ODS-Cu) is superior in thermal conductivity, electrical conductivity, heat resistance and friction tolerance, etc. Although the ODS-Cu can be expected to have various industrial applications, its joint with other materials is extremely difficult because of its intrinsic poor weldability. The research group of Dr. Masayuki Tokitani in the National Institutes of Natural Sciences (NINS) National Institute for Fusion Science (NIFS) has developed an extremely novel joint technique that enables us to fabricate any component made of ODS-Cu. This technique highly contributes to producing the efficient heat removal component for the fusion reactor.

Copper alloys, e.g. ODS-Cu and tungsten (W) are supposed to be used in the component for which the highest heat removal performance is required in a fusion reactor. This component is called "divertor". High heat influx outcoming from high temperature plasma in a fusion reactor is received by the W armor of the divertor. The accepted thermal energy is then transferred to the cooling water through the ODS-Cu heat sink. For the conventional cooling structure, a cylindrical cooling flow path channel is machined in the heat sink. Recently, a new cooling structure is expected to improve the heat removal performance. The new structure has a rectangular shaped cooling flow path channel and V-shaped staggered ribs on the top wall of the flow path (Fig. 1). In order to make the new structure, we must seal the pre-processed cooling channel with the lid made of ODS-Cu or stainless steel (SUS). Since this sealing must prevent any leakage of cooling water or air, the leak-tight joint technique between ODS-Cu and ODS-Cu (ODS-Cu/ODS-Cu) and SUS and ODS-Cu (SUS/ODS-Cu) must be developed. Furthermore, after the new structure of the heat sink is obtained, we have to joint the W armor tiles on to it. This means that multi-step jointing should be required to fabricate the single heat removal component.

In order to fabricate the new type of the heat removal component, the research group has developed an extremely novel joint technique named "Advanced Multi-Step Brazing (AMSB)." Generally, the "brazing" is a popular joint technique of two materials, as in the following procedures. First, a filler material is inserted into the joint interface of the two materials. Second, the entire structure is heated up to the melting temperature of the filler material. After the cooling down phase of the heat treatment, the two materials are jointed by the adhesive force of post-solidified filler material. By advancing the conventional brazing, the research group had already developed the technique to tightly joint ODS-Cu and W in 2016. In this technique named "advanced brazing technique (ABT)," the BNi-6 (Ni-11%P) is used as filler material, and a compressive load with ~0.54 MPa is applied in the direction perpendicular to the joint interface by using carbon springs and flanges. Then, the post set-up of entire structure is heated up to be 960 degrees Celsius to melting the filler material (Fig. 2). This time, the research group has conducted the brazing test many times to find the optimized brazing conditions such as heating temperature, time and compressive load for leak-tight joint. Consequently, they found the optimized conditions to realize all of the following special features.

(1) The joint can be applied for the combination of ODS-Cu/ODS-Cu and SUS/ODS-Cu.
(2) The joint is completely leak tight.
(3) The joint has areal contact, not line- or spot-like contact.
(4) The joint strength is as high as the original strength of ODS-Cu.
(5) The joint does not degrade even after a repetitive (brazing) heat treatment.

By applying the special features, the AMSB enables us to produce the new structure of the ODS-Cu heat sink.

The new type of the divertor heat removal component was successfully produced by using the AMSB. This component showed an excellent heat removal capability under the reactor-relevant conditions with ~30 MW/m2 (Fig. 3). This heat removal capability is the world's highest heat removal performance to date.

Associate Professor Tokitani in the research team states, "The AMSB can be useful for jointing ODC-Cu with other materials besides SUS and W. We would like to apply this technique developed in fusion research to industrial applications in the future."

A new tool developed by the University of Cordoba, in collaboration with the Nuclear Medicine Unit at the Hospital Reina Sofía, could allow healthcare personnel to diagnose different degrees of Parkinson's, a disease that, according to World Health Organization (WHO) data, affects 7 million people worldwide.

To date, according to AYRNA group researcher Javier Barbero, "most diagnoses only determine whether or not the patient suffers from this disease." The research team has developed a system that makes it possible to specify the phase it is in, distinguishing between four different ones, based on severity.

Specifically, this new methodology combines Artificial Intelligence and the use of three-dimensional images of the area of the brain in which the neuronal degeneration is occurring. To do this, the research team has analysed, voxel by voxel (the equivalent of a 3D pixel), more than 500 photographs of the brains of people with symptoms compatible with the disease. The result is a mathematical algorithm that, after having processed all this information, is capable of estimating, once the image of the patient's brain has been scanned, the severity of the disease, based on neuron damage.

"The new tool produces this estimate automatically, providing an initial diagnosis that, of course, then has to be confirmed by the medical staff, with the images in front of them," explained Pedro Antonio Gutiérrez, another of the study's authors, together with César Hervás, Antonio Durán and Julio Camacho.

The researcher explained that the algorithm is capable of determining "which scanned areas of the brain are the most important and, therefore, those on which specialized personnel should focus their attention to confirm the diagnosis". But, why are some areas more important than others?

The answer: dopamine

Parkinson's Disease triggers a loss of density in the proteins responsible for transporting dopamine, aneurotransmitter essential to the control of movement. These 3D images are capable of detecting the density of these proteins and ascertaining the places in the brain where they are found, which offers clues to the severity of the disease.

Thus, the project "does not seek to substitute the assessments of specialized personnel, but rather to offer support for medical decision-making", said César Hervás, the AYRNA group's principal investigator. In any case, determining more precisely the phase this condition is in could help to adjust the amount of medication necessary, thus leading to better treatments for a chronic disease for which there is still no cure, though its prognosis has notably improved thanks to advances in neurology and the development of new drugs.

The process has also been validated through two different methodologies, both published in scientific journals. The first of them uses classic ordinal classification techniques, while the second is based on "Convolutional Neural Networks" (CNN), a type of Artificial Intelligence model that is very effective with vision-related tasks such as image classification.

A new robot - named WomBot - that can be used to explore and study wombat burrows is presented in a study published in the journal SN Applied Sciences.

Wombats reside and sleep in burrows and occupy a different burrow every four to ten days. Parasitic mites that cause sarcoptic mange, a serious disease affecting wombats, are thought to be transmitted when wombats occupy each other's burrows but it has not been clear whether conditions within burrows promote this transmission.

Researchers from La Trobe University and the University of Tasmania, Australia developed WomBot in order to study environmental conditions within wombat burrows. The robot is remotely operated and moves using continuous tracks, similar to a tank tread. Its top speed is 0.15 metres per second and it is able to climb inclines of up to 22 degrees. Environmental sensors in WomBot can measure the temperature and humidity of a burrow while a gripper attached to its front can be used to place and retrieve additional environmental sensors. Front and rear cameras enable burrow visualisation. WomBot is 300 millimetres long and weights two kilograms, equivalent to one third of the length and one tenth of the weight of a wombat.

Robert Ross, the corresponding author, said: "Wombat burrows are challenging to study as they are narrow, muddy, can be dozens of metres long and contain steep sections and sharp turns. WomBot allows us to enter and explore these burrows without destroying them or using expensive ground-penetrating radar. This can help us better understand the environmental conditions within burrows that may facilitate sarcoptic mange transmission."

The authors used WomBot to explore a total of 30 wombat burrows in Tasmania during September 2020. They found that the average temperature inside the burrows was 15 degrees Celsius and the average relative humidity was 85%. Environmental sensors left in the burrows over a 24 hour period recorded that temperatures remained mostly constant at 11 degrees Celsius and relative humidity ranged from 85 to 95%. Temperatures outside of the burrow during this time ranged from three to 15 degrees Celsius and relative humidity ranged from 70 to 95%.

Previous research has suggested that the conditions that promote maximum survival of scabies mites are temperatures around 10 degrees Celsius and relative humidity between 75 and 97%, similar to the conditions observed inside the wombat burrows. The authors estimate that female mites could survive for between nine and ten days at the entrance to a wombat burrow and between 16 and 18 days inside a burrow, potentially allowing them to infect wombats.

Robert Ross said: "Our findings indicate that the environmental conditions within wombat burrows may facilitate sarcoptic mange transmission by promoting mite survival. WomBot could potentially be used to help reduce the spread of sarcoptic mange by delivering insecticide or ensuring burrows are empty before being temporarily heated in order to eradicate mites."

The authors caution that the environmental conditions observed over a 24-hour period within the burrows used in their study may not be representative of conditions inside all wombat burrows throughout the year. Further research could use WomBot to create three dimensional reconstructions of burrows or to collect soil samples from burrows in order to study mite prevalence.

Weakened electrical signals in the brain may be an early warning sign of age-related neurodegenerative diseases such as Alzheimer's disease, suggests a study published today in eLife.

The findings hint at new ways to identify early on patients who may have an age-related brain disease. They also provide new insights on the changes that occur in the brain as these diseases develop.

"As tools for detecting Alzheimer's disease early are limited, there is a need to develop a reliable, non-invasive test that would enable early diagnosis," says first author Murty Dinavahi, who was a PhD Research Scholar at the Centre for Neuroscience, Indian Institute of Science (IISc), Bengaluru, India, at the time the study was carried out, and is now a Postdoctoral Associate at the University of Maryland, US.

Previous studies in mice with a condition similar to Alzheimer's disease had suggested that weakened gamma brain waves may be an early sign of disease. Based on these findings, Murty and colleagues conducted a community-based study on around 250 elderly subjects. They compared gamma wave activity in 12 people diagnosed with mild cognitive impairment, and five with Alzheimer's disease, with their healthy peers.

The researchers used a technique called electroencephalography to measure electrical activity in the participants' brains while they viewed black and white patterns on a screen. These patterns are known to induce gamma oscillations in the part of the brain that processes visual information. The team also monitored the participants' eye movements during the experiments.

Their results showed that people who had been diagnosed with mild cognitive impairment or Alzheimer's disease had weaker gamma waves in their brain than healthy individuals of the same age.

"We observed reductions in the strength of gamma waves in early stages of age-related cognitive decline," Murty says. "Changes in these electrical signals could provide an early warning sign of an impending disease." He adds that an early diagnosis could help individuals put care plans in place or allow them to begin treatments sooner.

"Our work provides a low-cost and non-invasive way to detect early signs of Alzheimer's disease," concludes senior author Supratim Ray, Associate Professor at the Centre for Neuroscience, IISc. "This could be useful for clinicians and scientists studying early changes that take place in the brain during age-related neurodegenerative diseases, and potentially lead to new ways to diagnose and treat these conditions."

Difficulty sleeping, sleep apnea and narcolepsy are among a range of sleep disorders that thousands of Danes suffer from. Furthermore, it is estimated that sleep apnea is undiagnosed in as many as 200,000 Danes.

In a new study, researchers from the University of Copenhagen's Department of Computer Science have collaborated with the Danish Center for Sleep Medicine at the danish hospital Rigshospitalet to develop an artificial intelligence algorithm that can improve diagnoses, treatments, and our overall understanding of sleep disorders.

"The algorithm is extraordinarily precise. We completed various tests in which its performance rivaled that of the best doctors in the field, worldwide," states Mathias Perslev, a PhD at the Department of Computer Science and lead author of the study, recently published in the journal npj Digital Medicine (link).

Can support doctors in their treatments

Today's sleep disorder examinations typically begin with admittance to a sleep clinic. Here, a person's night sleep is monitored using various measuring instruments. A specialist in sleep disorders then reviews the 7-8 hours of measurements from the patient's overnight sleep.

The doctor manually divides these 7-8 hours of sleep into 30-second intervals, all of which must be categorized into different sleep phases, such as REM (rapid eye movement) sleep, light sleep, deep sleep, etc. It is a time-consuming job that the algorithm can perform in seconds.

"This project has allowed us to prove that these measurements can be very safely made using machine learning - which has great significance. By saving many hours of work, many more patients can be assessed and diagnosed effectively," explains Poul Jennum, professor of neurophysiology and Head of the Danish Center for Sleep Medicine.

In the Capital Region of Denmark alone, more than 4,000 polysomnography tests - known as PSG or sleep studies - are conducted annually on patients with sleep apnea and more complicated sleeping disorders. It takes 1.5-3 hours for a doctor to analyze a PSG study. Thus, in the Capital Region of Denmark alone, between 6,000 and 12,000 medical hours could be freed up by deploying the new algorithm.

The algorithm functions across sleep clinics and patient groups

By collecting data from a variety of sources, the researchers behind the algorithm have been able to ensure optimal functionality. In all, 20,000 nights of sleep from the United States and a host of European countries have been collected and used to train the algorithm.

"We have collected sleep data from across continents, sleep clinics and patient groups. The fact that the algorithm works well under such diverse conditions is a breakthrough," explains Mathias Perslev and Christian Igel, who led the project on the computer science side, adding:

"Achieving this kind of generalization is one of the greatest challenges in medical data analysis."

They hope that the algorithm will serve to help doctors and researchers around the world to learn more about sleep disorders in the future. The sleep analysis software is freely available at sleep.ai.ku.dk and can be used by anyone, anywhere - including places where there isn't a sleep clinic around the corner.

"Just a few measurements taken by common clinical instruments are required for this algorithm. So, use of this software could be particularly relevant in developing countries where one may not have access to the latest equipment or an expert," says Mathias Perslev.

The researchers are now working with Danish physicians to get the software and algorithm approved for clinical use.