Tech

WASHINGTON -- Researchers have developed a new bio-inspired medical endoscope that can acquire 3D visible light and near-infrared fluorescence images at the same time. It features an optical design that combines the high-resolution 3D imaging of human vision with the mantis shrimp's capability to simultaneously detect multiple wavelengths of light.

Endoscopes with 3D imaging capability can help surgeons precisely locate diseased tissue. Adding fluorescence imaging can make cancerous tissue light up for easier removal or highlight critical parts of the anatomy that need to be avoided during surgery.

In The Optical Society (OSA) journal Optics Express, Chenyoung Shi from the Chinese Academy of Sciences and colleagues describe and demonstrate the new multimodal endoscope. Although this is an early demonstration, the new endoscope is designed to directly replace existing endoscopes without requiring clinicians to learn how to use a new instrument.

"Existing fluorescence 3D endoscopes require surgeons to switch working modes during operation to see the fluorescence images," said Shi. "Because our 3D endoscope can acquire visible and fluorescent 3D images simultaneously, it not only provides more visual information but can also greatly shorten the operation time and reduce risks during surgery."

Aiding robotic surgery

Although it could be used for any endoscopic procedure, the researchers designed the new multimodal endoscope for robotic surgery systems. These systems help increase the precision and accuracy of minimally invasive procedures and can help surgeons perform complicated tasks in confined areas of the body. For robotic surgery, the enhanced visual information provided by the new endoscope could help a surgeon who may be in a different room from the patient clearly distinguish various types of tissue in the surgical field.

"Although today's robotic surgical systems require the surgeon to be close by, robotic surgery based on this multimodal 3D endoscope might one day allow surgeons to remotely perform procedures in faraway locations," said Shi. "This could help solve the problem of uneven distribution of medical resources and benefit people who live in areas with relatively poor medical conditions."

The new multimodal endoscope achieves high-resolution 3D imaging using two optical systems to form a binocular design much like that of human eyes. However, in this case, the optical design can accommodate both visible light like human eyes and the near-infrared wavelengths required for fluorescence imaging. This light is detected by a sensor inspired by the compound eyes of mantis shrimp, which not only detect multispectral information but also recognize polarized light. The sensor detects multiple parts of the electromagnetic spectrum by using pixels with different spectral and polarization responses.

To obtain high-quality 3D images, the binocular optical system must have two optical systems with exactly the same parameters. "This places stringent requirements on the processing accuracy of optical components," said Shi. "We were able to accomplish this accuracy using precision optical processing and combined this with chip-based spectroscopy technology to make this multimodal 3D endoscope possible."

Combining visible and fluorescence images

To test the new endoscope, the researchers analyzed its resolution, fluorescence imaging capability and ability to simultaneously obtain 3D images with near-infrared and visible color information. The endoscope performed well and achieved a resolution as high as 7 line pairs per millimeter with visible light-- the same as the best 3D endoscopes used today -- and 4 line pairs per millimeter under near-infrared illumination.

They then used the endoscope to acquire visible color and near-infrared ?uorescence images of three concentrations of indocyanine green. This near-infrared fluorescent label is approved by the FDA and used to label tumor tissues. Although the three samples could not be distinguished by the human eye, they could be clearly distinguished using the multimodal 3D endoscope. The researchers also tested the endoscope's 3D imaging performance by using it to image a toy with many crisscross parts. The endoscope was able to produce 3D images that did not cause eye fatigue, even after a long period of viewing.

The researchers plan to use the 3D endoscope to perform additional biological and clinical imaging. They also plan to incorporate more wavelengths and the ability to sense polarization to provide even more visual information.

Substances present in cooked meats are associated with increased wheezing in children, Mount Sinai researchers report. Their study, published in Thorax, highlights pro-inflammatory compounds called advanced glycation end-products (AGEs) as an example of early dietary risk factors that may have broad clinical and public health implications for the prevention of inflammatory airway disease.

Asthma prevalence among children in the United States has risen over the last few decades. Researchers found that dietary habits established earlier in life may be associated with wheezing and potentially the future development of asthma.

Researchers examined 4,388 children between 2 and 17 years old from the 2003-2006 National Health and Nutrition Examination Survey (NHANES), a program of the National Center for Health Statistics, which is part of the U.S. Centers for Disease Control and Prevention. It is designed to evaluate the health and nutritional status of adults and children in the United States through interviews and physical examinations.

The researchers used NHANES survey data to evaluate associations between dietary AGE and meat consumption frequencies, and respiratory symptoms. They found that higher AGE intake was significantly associated with increased odds of wheezing, importantly including wheezing that disrupted sleep and exercise, and that required prescription medication. Similarly, higher intake of non-seafood meats was associated with wheeze-disrupted sleep and wheezing that required prescription medication.

"We found that higher consumption of dietary AGEs, which are largely derived from intake of non-seafood meats, was associated with increased risk of wheezing in children, regardless of overall diet quality or an established diagnosis of asthma," said Jing Gennie Wang, MD, lead author of the study, and a former fellow in Pulmonary, Critical Care and Sleep Medicine at the Icahn School of Medicine at Mount Sinai.

"Research identifying dietary factors that influence respiratory symptoms in children is important, as these risks are potentially modifiable and can help guide health recommendations. Our findings will hopefully inform future longitudinal studies to further investigate whether these specific dietary components play a role in childhood airways disease such as asthma," said Sonali Bose, MD, senior author, and Assistant Professor of Pulmonary, Critical Care and Sleep Medicine and Pediatrics at Icahn School of Medicine at Mount Sinai.

Paper snowflakes, pop-up children's books and elaborate paper cards are of interest to more than just crafters. A team of Northwestern University engineers is using ideas taken from paper-folding practices to create a sophisticated alternative to 3D printing.

Kirigami comes from the Japanese words "kiru" (to cut) and "kami" (paper) and is a traditional form of art in which paper is precisely cut and transformed into a 3D object. Using thin films of material and software to select exact geometric cuts, engineers can create a wide range of complex structures by taking inspiration from the practice.

Research, published in 2015, showed promise in the kirigami "pop-up" fabrication model. In this iteration, the ribbon-like structures created by the cuts were open shapes, with limited ability to achieve closed shapes. Other research building on the same inspiration mainly demonstrates that kirigami can be applied at a macroscale with simple materials like paper.

But new research published today (Dec. 22) in the journal Advanced Materials advances the process a step further.

Horacio Espinosa, a mechanical engineering professor in the McCormick School of Engineering, said his team was able to apply concepts of design and kirigami to nanostructures. Espinosa led the research and is the James N. and Nancy J. Farley Professor in Manufacturing and Entrepreneurship.

"By combining nanomanufacturing, in situ microscopy experimentation, and computational modeling, we unraveled the rich behavior of kirigami structures and identified conditions for their use in practical applications," Espinosa said.

The researchers start by creating 2D structures using state-of-the-art methods in semiconductor manufacturing and carefully placed "kirigami cuts" on ultrathin films. Structural instabilities induced by residual stresses in the films then create well-defined 3D structures. The engineered kirigami structures could be employed in a number of applications ranging from microscale grippers (e.g. cell picking) to spatial light modulators to flow control in airplane wings. These capabilities position the technique for potential applications in biomedical devices, energy harvesting, and aerospace.

Typically, there has been a limit to the number of shapes that can be created by a single kirigami motif. But by using variations in the cuts, the team was able to demonstrate film bending and twisting that result in a wider variety of shapes -- including both symmetrical and asymmetrical configurations. The researchers demonstrated for the first time that structures at microscales, using film thicknesses of a few tens of nanometers, can achieve unusual 3D shapes and present broader functionality.

For example, electrostatic microtweezers snap close, which can be harsh on soft samples. By contrast, kirigami-based tweezers can be engineered to precisely control the grabbing force by tuning the amount of stretching. In this and other applications, the ability to design cut locations and predict structural behavior based on computer simulations takes out trial and error, saving money and time in the process.

As their research advances, Espinosa says his team plans to explore the large space of kirigami designs, including array configurations, in order to achieve a larger number of possible functionalities. Another area for future research is the embedding of distributed actuators for kirigami deployment and control. By looking into the technique further, the team believes kirigami can have implications in architecture, aerospace and environmental engineering.

Damien D'Amours and his team at the Ottawa Institute of Systems Biology needed three years to discover the molecular defects associated with the LIC Syndrome, a serious genetic disorder that affects young children and result in acute respiratory distress, immune deficiency and abnormal chromosomes.

Onset of symptoms occurs in the first few months after birth in infants suffering from Lung disease Immunodeficiency and Chromosome breakage (LIC). Typically, patients experience failure to thrive and immune deficiency, which can eventually progress to fatal pediatric pulmonary disease in early childhood. The disease is caused by small inactivating mutations in NSMCE3, a gene encoding an essential factor found in the nucleus of human cells.

This research represents one of the most important milestones in developing treatments to improve the lives of LIC syndrome patients. Damien D'Amours is a Full Professor in the Department of Cellular & Molecular Medicine of the Faculty of Medicine whose lab is focused understanding the mechanisms used by cells to promote efficient cell division and proliferation. He provided further insights into the study's findings.

What exactly have you discovered?

"We discovered how defects in a "DNA compaction machine" within our cells can cause a rare genetic disorder that kills young children (i.e., the LIC syndrome). We found the molecular cause by using an exciting mix of biophysics, advanced genetics and classical biochemistry to demonstrate that an enzyme has the rare ability to compact DNA within our cells."

How did you do it?

"We developed a completely novel system to purify a human enzyme that nobody in the world has ever successfully purified - the "Smc5/6 complex." The Smc5/6 complex is a crucial effector of chromosome integrity, and our breakthrough allowed us to reveal the structure of the enzyme and its powerful ability to compact DNA structure in space. We then modelled the mutations causing the LIC syndrome in our system and showed that the mutations affect ability of the Smc5/6 complex to repair chromosomes in cells, thus explaining how LIC mutations affect the ability of cells to maintain healthy genomes."

You used the "systems biology" approach to reach your conclusions; please explain this.

"The advent of systems biology has revolutionized biomedical research in recent years. This approach relies on the use of integrative "omics" technologies and model organisms to provide a systems-level understanding of human diseases. (Omics is a general term to describe "large-scale genomics, proteomics, and metabolomics technologies.") The University of Ottawa has been at the forefront of this revolution in research with the creation of the Ottawa Institute of Systems Biology (OISB). We took advantage of the systems biology approach to develop completely new systems to purify an enzyme never purified before. Then we used innovative mix of biophysics, proteomics and classical biochemistry to reveal the mode of action of the Smc5/6 complex and how mutations in this complex can cause severe defects in DNA repair."

Why is this an important find?

"My research team and our collaborators are performing research at the absolute cutting-edge of our field and, as the leading laboratory on this project, we feel our research represents one of the most important milestones on the way to devise treatments for LIC syndrome patients. Prior to our work, nobody knew the biochemical cause for the LIC syndrome and how the enzyme mutated in this disease might affect the cells of patients/children; we provided answers to these fundamental questions."

BEER-SHEVA, Israel, December 22, 2020 - Online users are more likely to reveal private information based on how website forms are structured to elicit data, Ben-Gurion University of the Negev (BGU) researchers have determined.

The intriguing study, "Online Disclosure Depends on How You Ask for Information," was presented at the 41st International Conference on Information Systems (ICIS 2020), held virtually this year, December 12-16. The BGU researchers' findings convey significant implications for user privacy as well as online data capture.

"The objective was to demonstrate that we are able to cause smartphone and PC users of online services to disclose more information by measuring the likelihood that they sign-up for a service simply by manipulating the way information items (name, address, email) were presented," says Prof. Lior Fink, head of the BGU Behavioral Information Technologies (BIT) Lab and a member of the Department of Industrial Management and Engineering.

The BGU researchers showed that by using digital "foot-in-the-door" techniques, such as requesting personal information from less important to more private (ascending privacy-intrusion order), websites can successfully entice users to reveal more of their private information. Similarly, by placing each request on consecutive, separate webpages, users are more likely to reveal more private data. Websites can further manipulate their users by spreading out information requests over the course of several pages, rather than consolidating all requests on one page.

The researchers collaborated with Rewire, a Tel Aviv neobank (a virtual or online bank) providing international money transfer services. They examined the activities of 2,504 users who were asked to provide their country, full name, phone number, and email address as part of the sign-up process.

"We found that both manipulations independently increased the likelihood of sign-up and conversion," Fink says. "The ascending privacy intrusion manipulation increased sign-up by 35% and the multiple-page manipulation increased sign-up by 55%."

"The general public and regulators should be made aware of these vulnerabilities since it is so easy to capture more private information, despite their privacy concerns," says lead researcher and BGU student Naama Ilany-Tzur. "At the same time, this research has important marketing implications as legitimate companies and marketers are always seeking to maximize the amount of data they can capture on individuals and the optimal way to achieve this."

A team of scientists from RUDN University and the Dokuchyaev Soil Science Institute developed a method for identifying the color of soil at different depths and the structure of soil profile using ground-penetrating radar. With this methodology, scientists can identify the chemical composition of the soil and classify it for potential use in construction, agriculture, or mining without digging soil sections. The results of the study were published in the Eurasian Soil Science journal.

Color is one of the main indicators of soil properties. Based on it, a specialist can identify the type of soil, humus content, soil density, humidity, salinity, and so on. For example, black soil is rich in humus, and soils with increased iron content usually have a reddish hue. To analyze the color of the soil, scientists have to dig a soil section which is quite a labor-intensive process. A team of scientists from RUDN University together with their colleagues from the Dokuchyaev Soil Science Institute suggested using ground-penetrating radar to determine the color of the soil at different depths. A GPR sends electromagnetic waves to the soil and registers a reflected signal.

"Color is one of the main properties of soils that has been used for their classification for a long time. That is why many names of soils are associated with color. Moreover, color is an integral indicator of many other characteristics of soils. Theoretically, this parameter could be measured with GPR. We wanted to confirm a correlation between the colors of soil layers and GPR profiling data," said Prof. Igor Savin, an Academician of the Russian Academy of Sciences and a Ph.D. in Agricultural Sciences from the Faculty of Ecology, RUDN University.

The team conducted an experiment in Kamennaya Steppe (Voronezh Region) because this area is known for a large variety of soil types and conditions. The scientists chose seven sites and probed the soils there with ground-penetrating radar. They also took 30 soil samples from each site: one from each 10 cm deep layer down to the depth of 3 m. The samples were dried and ground to identify the color. To do so, the team analyzed their reflective capacity that was averaged to three wavelength ranges: red (610-700 nm), green (520-540 nm), and blue (450-475 nm). After that, the team compared the radar readings with the colors of soil samples and developed a correlation model. The colors calculated with the use of the model matched the actual ones in 80% of cases. Therefore, the new method can be used to determine soil color on other sites in the territory of the study without digging soil sections.

Currently, the model is only applicable to the territory of Kamennaya Steppe because it was calibrated based on the samples collected there. In the future, the team hopes to adapt it to other areas.

"Our models cannot be used in territories with different soil covering. However, it is not a disadvantage, but rather a peculiarity of our method. To secure modeling accuracy, the model should include information about soil colors that are typical for the area of the study. In the initial stages, control soil sections would still have to be made using traditional methods. However, as soon as we accumulate enough field data, we would be able to eliminate this step, and no digging would be required to identify soil color at any depth," added Prof. Igor Savin from RUDN University.

A joint research team co-led by City University of Hong Kong (CityU) has developed a novel computational tool that can reconstruct and visualise three-dimensional (3D) shapes and temporal changes of cells, speeding up the analysing process from hundreds of hours by hand to a few hours by the computer. Revolutionising the way biologists analyse image data, this tool can advance further studies in developmental and cell biology, such as the growth of cancer cells.

The interdisciplinary study was co-led by Professor Yan Hong, Chair Professor of Computer Engineering and Wong Chung Hong Professor of Data Engineering in the Department of Electrical Engineering (EE) at CityU, together with biologists from Hong Kong Baptist University (HKBU) and Peking University. Their findings have been published in the scientific journal Nature Communications, titled "Establishment of a morphological atlas of the Caenorhabditis elegans embryo using deep-learning-based 4D segmentation".

The tool developed by the team is called "CShaper". "It is a powerful computational tool that can segment and analyse cell images systematically at the single-cell level, which is much needed for the study of cell division, and cell and gene functions," described Professor Yan.

Bottleneck in analysing massive amount of cell division data

Biologists have been investigating how animals grow from a single cell, a fertilised egg, into organs and the whole body through countless cell divisions. In particular, they want to know the gene functions, such as the specific genes involved in cell divisions for forming different organs, or what causes the abnormal cell divisions leading to tumourous growth.

A way to find the answer is to use the gene knockout technique. With all genes present, researchers first obtain cell images and the lineage tree. Then they "knock out" (remove) a gene from the DNA sequence, and compare the two lineage trees to analyse changes in the cells and infer gene functions. Then they repeat the experiment with other genes being knocked out.

In the study, the collaborating biologist team used Caenorhabditis elegans (C. elegans) embryos to produce terabytes of data for Professor Yan's team to perform computational analysis. C. elegans is a type of worm which share many essential biological characteristics with humans and provide a valuable model for studying the tumour growth process in humans.

"With estimated 20,000 genes in C. elegans, it means nearly 20,000 experiments would be needed if knocking out one gene at a time. And there would be an enormous amount of data. So it is essential to use an automated image analysis system. And this drives us to develop a more efficient one," he said.

Breakthrough in segmenting cell images automatically

Cell images are usually obtained by laser beam scanning. The existing image analysis systems can only detect cell nucleus well with a poor cell membrane image quality, hampering reconstruction of cell shapes. Also, there is a lack of reliable algorithm for the segmentation of time-lapsed 3D images (i.e. 4D images) of cell division. Image segmentation is a critical process in computer vision that involves dividing a visual input into segments to simplify image analysis. But researchers have to spend hundreds of hours labelling many cell images manually.

The breakthrough in CShaper is that it can detect cell membranes, build up cell shapes in 3D, and more importantly, automatically segment the cell images at the cell level. "Using CShaper, biologists can decipher the contents of these images within a few hours. It can characterise cell shapes and surface structures, and provide 3D views of cells at different time points," said Cao Jianfeng, a PhD student in Professor Yan's group, and a co-first author of the paper.

To achieve this, the deep-learning-based model DMapNet developed by the team plays a key role in the CShaper system. "By learning to capture multiple discrete distances between image pixels, DMapNet extracts the membrane contour while considering shape information, rather than just intensity features. Therefore CShaper achieved a 95.95% accuracy of identifying the cells, which outperformed other methods substantially," he explained.

With CShaper, the team generated a time-lapse 3D atlas of cell morphology for the C. elegans embryo from the 4- to 350-cell stages, including cell shape, volume, surface area, migration, nucleus position and cell-cell contact with confirmed cell identities.

Advancing further studies in tumour growth

"To the best of our knowledge, CShaper is the first computational system for segmenting and analysing the images of C. elegans embryo systematically at the single-cell level," said Mr Cao. "Through close collaborations with biologists, we proudly developed a useful computer tool for automated analysis of a massive amount of cell image data. We believe it can promote further studies in developmental and cell biology, in particular in understanding the origination and growth of cancer cells," Professor Yan added.

They also tested CShaper on plant tissue cells, showing promising results. They believe the computer tool can be adopted to other biological studies.

Northwestern researchers have developed a new microscopy method that allows scientists to see the building blocks of "smart" materials being formed at the nanoscale.

The chemical process is set to transform the future of clean water and medicines and for the first time people will be able to watch the process in action.

"Our method allows us to visualize this class of polymerization in real time, at the nanoscale, which has never been done before," said Northwestern's Nathan Gianneschi. "We now have the ability to see the reaction taking place, see these nanostructures being formed, and learn how to take advantage of the incredible things they can do."

The research was published today (Dec. 22) in the journal Matter.

The paper is the result of a collaboration between Gianneschi, the associate director of the International Institute for Nanotechnology and the Jacob and Rosalind Cohn Professor of Chemistry in the Weinberg College of Arts and Sciences, and Brent Sumerlin, the George and Josephine Butler Professor of Polymer Chemistry in the College of Liberal Arts & Sciences at the University of Florida.

Dispersion polymerization is a common scientific process used to make medicines, cosmetics, latex and other items, often on an industrial scale. And at the nanoscale, polymerization can be used to create nanoparticles with unique and valuable properties.

These nanomaterials hold great promise for the environment, where they can be used to soak up oil spills or other pollutants without harming marine life. In medicine, as the foundation of "smart" drug delivery systems, it can be designed to enter human cells and release therapeutic molecules under specified conditions.

There have been difficulties in scaling up production of these materials. Initially, production was hampered by the time-consuming process required to create and then activate them. A technique called polymerization-induced self-assembly (PISA) combines steps and saves time, but the molecules' behavior during this process has proven difficult to predict for one simple reason: Scientists were unable to observe what was actually happening.

Reactions at the nanoscale are far too small to be seen with the naked eye. Traditional imaging methods can only capture the end result of polymerization, not the process by which it occurs. Scientists have tried to work around this by taking samples at various points in the process and analyzing them, but using only snapshots failed to tell the full story of chemical and physical changes occurring throughout the process.

"It's like comparing a few photos of a football game to the information contained in a video of the whole game," said Gianneschi. "If you understand the pathway by which a chemical forms, if you can see how it occurred, then you can learn how to speed it up, and you can figure out how to perturb the process so you get a different effect."

Transmission electron microscopy (TEM) is capable of taking images at a sub-nanometer resolution, but it is generally used for frozen samples, and doesn't handle chemical reactions as well. With TEM, an electron beam is fired through a vacuum, toward the subject; by studying the electrons that come out the other side, an image can be developed. However, the quality of the image depends on how many electrons are fired by the beam - and firing too many electrons will affect the outcome of the chemical reaction. In other words, it's a case of the observer effect - watching the self-assembly could alter or even damage the self-assembly. What you end up with is different from what you would have had if you weren't watching.

To solve the problem, the researchers inserted the nanoscale polymer materials into a closed liquid cell that would protect the materials from the vacuum inside the electron microscope. These materials were designed to be responsive to changes in temperature, so the self-assembly would begin when the inside of the liquid cell reached a set temperature.

The liquid cell was enclosed in a silicon chip with small, but powerful, electrodes that serve as heating elements. Embedded in the chip is a tiny window - 200 x 50 nanometers in size - that would allow a low-energy beam to pass through the liquid cell.

With the chip inserted into the holder of the electron microscope, the temperature inside the liquid cell is raised to 60?C, initiating the self-assembly. Through the tiny window, the behavior of the block copolymers and the process of formation could be recorded.

When the process was complete, Gianneschi's team tested the resulting nanomaterials and found they were the same as comparable nanomaterials produced outside a liquid cell. This confirmed that the technique - which they call variable-temperature liquid-cell transmission electron microscopy (VC-LCTEM) - can be used to understand the nanoscale polymerization process as it occurs under ordinary conditions.

Of particular interest are the shapes that are generated during polymerization. At different stages the nanoparticles may resemble spheres, worms or jellyfish - each of which confers different properties upon the nanomaterial. By understanding what is happening during self-assembly researchers can begin to develop methods to induce specific shapes and tune their effects.

"These intricate and well-defined nanoparticles evolve over time, forming and then morphing as they grow," Sumerlin said. "What's incredible is that we're able to see both how and when these transitions occur in real time."

Gianneschi believes that insights gained from this technique will lead to unprecedented possibilities for the development and characterization of self-organizing soft matter materials - and scientific disciplines beyond chemistry.

"We think this can become a tool that's useful in structural biology and materials science too," said Gianneschi. "By integrating this with machine learning algorithms to analyze the images, and continuing to refine and improve the resolution, we're going to have a technique that can advance our understanding of polymerization at the nanoscale and guide the design of nanomaterials that can potentially transform medicine and the environment."

We know that the brain can direct thoughts, but how this is achieved is difficult to determine. Researchers at the Sainsbury Wellcome Centre have devised a brain machine interface (BMI) that allows mice to learn to guide a cursor using only their brain activity. By monitoring this mouse-controlled mouse moving to a target location to receive a reward, the researchers were able to study how the brain represents intentional control.

The study, published today in Neuron, sheds light on how the brain represents causally-controlled objects. The researchers found that when mice were controlling the cursor, brain activity in the higher visual cortex was goal-directed and contained information about the animal's intention. This research could one day help to improve BMI design.

"Brain machine interfaces are devices that allow a person or animal to control a computer with their mind. In humans, that could be controlling a robotic arm to pick up a cup of water, or moving a cursor on a computer to type a message using the mind. In animals, we are using these devices as models for understanding how to make BMIs better," said the paper's first author, Dr Kelly Clancy, who completed the study at the Sainsbury Wellcome Centre, University College London, following previous work at Biozentrum, University of Basel.

"Right now, BMIs tend to be difficult for humans to use and it takes a long time to learn how to control a robotic arm for example. Once we understand the neural circuits supporting how intentional control is learned, which this work is starting to elucidate, we will hopefully be able to make it easier for people to use BMIs," said co-author of the paper, Professor Tom Mrsic-Flogel, Director of the Sainsbury Wellcome Centre, University College London.

Traditionally it has been difficult to study how causally-controlled objects are represented in the brain. Imagine trying to determine how the brain represents a cursor it is controlling versus a cursor it is passively watching. There are motor signals in the first case but not in the second, so it is difficult to compare the two. With BMIs, the subject doesn't physically move, so a cleaner comparison can be made.

In this study, the researchers used a technique called widefield brain imaging, which allowed them to look at the whole dorsal surface of the cortex while the animal was using the BMI. This technique enabled an unbiased screen of the cortex to locate the areas that were involved in learning to intentionally control the cursor.

Visual cortical areas in mice were found to be involved during the task. These areas included the parietal cortex, an area of the brain implicated in intention in humans.

"Researchers have been studying the parietal cortex in humans for a long time. However, we weren't necessarily expecting this area to pop out in our unbiased screen of the mouse brain. There seems to be something special about parietal cortex as it sits between sensory and motor areas in the brain and may act as a way station between them," added Dr Kelly Clancy.

By delving deeper into how this way station works, the researchers hope to understand more about how control is exerted by the brain. In this study, mice learned to map their brain activity to sensory feedback. This is analogous to how we learn to interact with the world--for example, we adjust how we use a computer mouse depending on its gain setting. Our brains build representations of how objects typically behave, and execute actions accordingly. By understanding more about how such rules are generated and updated in the brain, the researchers hope to be able to improve BMIs.

Scientists from the United States, China, and Russia have described the structure and properties of a novel hydrogen clathrate hydrate that forms at room temperature and relatively low pressure. Hydrogen hydrates are a potential solution for hydrogen storage and transportation, the most environmentally friendly fuel. The research was published in the journal Physical Review Letters.

Ice is a highly complex substance with multiple polymorphic modifications that keep growing in number as scientists make discoveries. The physical properties of ice vary greatly, too: for example, hydrogen bonds become symmetric at high pressures, making it impossible to distinguish a single water molecule, whereas low pressures cause proton disorder, placing water molecules in many possible spatial orientations within the crystal structure. The ice around us, including snowflakes, is always proton-disordered. Ice can incorporate xenon, chlorine, carbon dioxide, or methane molecules and form gas hydrates, which often have a different structure from pure ice. The vast bulk of Earth's natural gas exists in the form of gas hydrates.

In their new study, chemists from the United States, China, and Russia focused on hydrogen hydrates. Gas hydrates hold great interest both for theoretical research and practical applications, such as hydrogen storage. If stored in its natural form, hydrogen poses an explosion hazard, whereas density is way too low even in compressed hydrogen. That is why scientists are looking for cost-effective hydrogen storage solutions.

"This is not the first time we turn to hydrogen hydrates. In our previous research, we predicted a novel hydrogen hydrate with 2 hydrogen molecules per water molecule. Unfortunately, this exceptional hydrate can only exist at pressures above 380,000 atmospheres, which is easy to achieve in the lab but is hardly usable in practical applications. Our new paper describes hydrates that contain less hydrogen but can exist at much lower pressures," Skoltech professor Artem R. Oganov says.

The crystal structure of hydrogen hydrates strongly depends on pressure. At low pressures, it has large cavities which, according to Oganov, resemble Chinese lanterns, each accommodating hydrogen molecules. As pressure increases, the structure becomes denser, with more hydrogen molecules packed into the crystal structure, although their degrees of freedom become significantly fewer.

In their research published in the Physical Review Letters, the scientists from the Carnegie Institution of Washington (USA) and the Institute of Solid State Physics in Hefei (China) led by Alexander F. Goncharov, a Professor at these two institutions, performed experiments to study the properties of various hydrogen hydrates and discovered an unusual hydrate with 3 water molecules per hydrogen molecule. The team led by Professor Oganov used the USPEX evolutionary algorithm developed by Oganov and his students to puzzle out the compound's structure responsible for its peculiar behavior. The researchers simulated the experiment's conditions and found a new structure very similar to the known proton-ordered C1 hydrate but differing from C1 in water molecule orientations. The team showed that proton disorder should occur at room temperature, thus explaining the X-ray diffraction and Raman spectrum data obtained in the experiment.

Fuel cells based on methanol oxidation have a huge potential in the motor and technical industries. To increase their energy performance, scientists suggest using electrodes made of thin palladium-based metallic glass films. A group of researchers from Far Eastern Federal University (FEFU), Austria, Turkey, Switzerland, and the UK has developed a new metallic glass for this application. The results were reported in the Nanoscale journal.

Thin films of palladium-based metallic glass, with gold and silicon additives (Pd79Au9Si12) are prospective materials for the production of energy generation catalysts for direct methanol fuel cells. In the future, they might replace less efficient and more expensive platinum-based elements.

Methanol fuel cells might be applicable in the vehicles and other special machinery which have to immediately generate force and therefore requires a special energy supply system. Additionally, such fuel cells could be used in telecommunications, data centers, and residential markets.

A metallic glass electrode developed by the team is 85% more efficient in oxidizing methanol than its platinum-based analogs. Moreover, because of its amorphous structure, metallic glass is more resistant to corrosion that poses a considerable threat for platinum-based electrodes with a crystalline structure.

"Potential use of metallic glass as a material for this type of electrodes has been previously described in the scientific literature but earlier papers had focused on macroscopic materials. We managed to confirm that nanosized thin films of metallic glass deposited on commonly used silicon substrates could effectively oxidize methanol. The films remain stable even after many working cycles. Our results considerably broaden the area of search for new materials for the energy sector," said Yurii Ivanov, a co-author of the work, and a docent at the Department of Computer Systems, FEFU School of Natural Sciences.

The new palladium-based metallic glass is the best material for methanol oxidation in fuel elements to this date and surpasses all existing developments and commercial solutions. According to the comparison with the most popular materials as an electrode for methanol oxidation, the new solution has one of the best performance values and the highest resistance to carbon monoxide poisoning that usually causes the degradation of electrodes.

To begin the practical implementation of the new development, the electrodes have to be scaled up and adjusted to actual fuel cells.

The team expects to continue searching for the best metallic glass composition to increase the stability and performance of fuel cells based on methanol oxidation. Currently, the efficiency factor of such cells varies from 40% to 60% (while that of a gasoline engine is only 20-30%).

FEFU runs the development of novel materials with unique properties and characteristics to engage in new generation electronics, green energy, construction, and other areas.

Earlier this year, a team of scientists from FEFU, MISiS, and MSU together with their foreign colleagues had found a way to saturate thin layers of metallic glass with hydrogen at room temperature, thus making one more step to solving one of the biggest issues of hydrogen energy. With such outcome researchers considerably expand the range of cost-effective, energy-efficient, and highly productive materials and methods for this field of the energy sector.

An international effort called Realizing Increased Photosynthetic Efficiency (RIPE) aims to transform crops' ability to turn sunlight and carbon dioxide into higher yields. To achieve this, scientists are analyzing thousands of plants to find out what tweaks to the plant's structure or its cellular machinery could increase production. University of Illinois researchers have revealed a new approach to estimate the photosynthetic capacity of crops to pinpoint these top-performing traits and speed up the screening process, according to a new study in the Journal of Experimental Botany. 

"Photosynthesis is the entry point for carbon dioxide to become all the things that allow plants to grow, but measuring canopy photosynthesis is really difficult," said Carl Bernacchi, a Research Plant Physiologist for the U.S. Department of Agriculture, Agricultural Research Service, who is based at Illinois' Carl R. Woese Institute for Genomic Biology. "Most methods are time-consuming and only measure a single leaf when it's the function of all leaves on all plants that really matters in agriculture."

Bernacchi's team uses two spectral instruments simultaneously--a hyperspectral camera for scanning crops and a spectrometer used to record very detailed information about sunlight--to quickly measure a signal called Solar Induced Fluorescence (SIF) that is emitted by plants when they become 'energy-excited' during photosynthesis. 

With this SIF signal, the team gains critical insights about photosynthesis that could ultimately lead to improving crop yields.  

They discovered that a key part of the SIF signal better correlates with photosynthetic capacity. This 'SIF yield' accounts for only a fraction of the energy emitted as SIF by plants to the energy captured by plants in total, but it carries important information. 

"With this insight, we can use a couple of instruments in a synergistic way to make more accurate estimates, and we can make these tools and pipelines more accessible to people who are interested in advancing the translation of photosynthesis," said Peng Fu, a postdoctoral researcher who led this work at Illinois.

In this study, they picked out specific bands of light that are known to be linked to SIF (and are already well understood physiologically) to better understand what hyperspectral data is actually needed to make these estimates.

In the past, they relied on expensive hyperspectral cameras that captured thousands of bands of light. "However, this study suggests that much cheaper cameras could be used instead now that we know what bands of light are needed," said Matthew Siebers, a postdoctoral researcher at Illinois.

These tools could speed up progress by orders of magnitude, said Katherine Meacham-Hensold, also a postdoctoral researcher at Illinois. "This technology is game-changing for researchers who are refining photosynthesis as a means to help realize the yields that we will need to feed humanity this century." 

NUST MISIS scientists found a way to reduce the cost of industrial and electronics heatsinks production up to 10 times. Consequently, the product itself would also cost less. The proposed methods presume the use of rubbers and silicon carbide as components, i.e. these components are mixed, pressed and sintered. The article on the research is published in Polymers.

Heat sinking in operating devices is a constant necessity as overheating inevitably shortens the service life of expensive equipment. One of the most popular heat sinking materials is graphite as it perfectly resists high temperatures. But this is an expensive material, since its production requires fairly "clean" conditions and exceptionally high-quality raw materials.

Scientists from NUST MISIS Center for Composite Materials found a way to significantly reduce the manufacturing cost of heat sinks. Instead of graphite, it was proposed to use polymer materials, rubbers with silicon carbide inclusions. In this case, the mass of inclusions can even exceed that of the base material, depending on the desired strength, ductility and heat resistance of the final material.

The production process is quite simple: the rubber mass is placed between two rollers that rotate towards each other at different speeds. Powdered silicon carbide is also added there. The rollers mix the materials and pull a uniform mass. Next, the mass is placed in a special press-form, where it is shaped in a desired way. Finally, the pressed billet is sintered at 360 °C.

"This is a very low-waste production: at the initial mixing stage, the mass is homogeneous, like plasticine or clay. Its remains can be immediately reused. In addition, both rubber and silicon carbide are inexpensive materials, if compared to graphite. The material obtained after sintering can withstand temperatures up to 300 °C, it perfectly sinks heat, and almost does not conduct current. That is, it can be used both in industry and in electronics", comments Andrey Stepashkin, researcher at NUST MISIS Center for Composite Materials.

However, as noted by scientists, their main achievement is not even in creating this particular material, but in working out the mechanical properties (strength, crack resistance, plasticity, etc.) that can be created using the methods described above. So, if silicon carbide is replaced with carbon fiber or, for example, boron nitride, such composites will find application in other areas of technology, such as conductive components of electronics.

Under certain conditions, antigen testing using self-collected swabs from the anterior nose may constitute a reliable alternative to antigen testing using nasopharyngeal swabs collected by health professionals. This is the conclusion drawn by a team of researchers from Charité - Universitätsmedizin Berlin and Heidelberg University Hospital. Results from their study have been published in the European Respiratory Journal*.

Rapid antigen tests may be less reliable than PCR tests, but their speed and simplicity make them an important complementary tool which can assist efforts to curb the current pandemic and reduce risks in certain day-to-day situations. Rapid antigen tests are intended for use at the point of care. Confirming whether or not a person is infected and contagious at the time of testing, they can provide results in less than 30 minutes. This type of test could therefore be used to make it safer for people to visit a loved one in a care home or hospital. Despite this potential, they are not yet widely used. One of the reasons for this is that, until now, most antigen testing systems used nasopharyngeal swabs which required collection by trained medical staff.

"There are two reasons why professional-collected nasopharyngeal swabs represent a barrier to the widespread use of rapid antigen testing," says Prof. Dr. Frank Mockenhaupt, Acting Director of Charité's Institute of Tropical Medicine and International Health. "Firstly, most people find a nasopharyngeal swab uncomfortable and, for this reason, are likely to avoid regular testing. Secondly, swabbing ties up staff resources, is complex and time-consuming, and necessitates the use of personal protective equipment." Working with PD Dr. Claudia Denkinger, Head of Heidelberg University Hospital's Clinical Tropical Medicine Section, Prof. Mockenhaupt therefore designed a study to test whether self-collected anterior nasal swabs administered under medical guidance could provide an alternative to a professional-collected nasopharyngeal swab.

The study, which was conducted at Charité's Ambulatory Coronavirus Testing Facility, took place between late September and mid-October. Individuals with characteristic SARS-CoV-2 symptoms wishing to take part in the study were instructed by medical staff as to the procedure for self-collected nasal swabs. Participants were instructed to insert a swab into both of their nostrils to a depth of 2 to 3 cm, rotating it against the nasal wall for a duration of 15 seconds. This was followed by a professional-collected nasopharyngeal swab. Both swab samples were analyzed on site using a commercially available rapid antigen test approved for use in Germany. Test results were then compared. Staff also collected a naso-oropharyngeal (combined nose and throat) swab which was analyzed using PCR testing. This served as a diagnostic reference standard.

39 out of a total of 289 participants (13.5 percent) were diagnosed with SARS-CoV-2, based on PCR results. In 31 of these infected individuals (nearly 80%), the professional-collected nasopharyngeal swabs also produced a positive result with the rapid antigen test. For self-collected swabs collected from the anterior nose, correct results were obtained in 29 (approximately 74 percent) of the infected individuals. "We had of course expected rapid antigen tests to be less sensitive than PCR," says PD Dr. Denkinger. "Upon closer inspection, however, cases of antigen tests missing infections were primarily associated with patients who had low viral loads." When looking exclusively at patients with high viral loads, the researchers found that the antigen tests correctly identified every single positive sample obtained via nasopharyngeal swab, and nearly 96 percent of self-collected swabs.

"This study shows that supervised, self-administered swabs are no less effective than professional-collected nasopharyngeal swabs when used with the antigen test selected for this research," explains PD Dr. Denkinger. She adds: "Firmer swabs, which are more suited for use in the anterior part of the nose, may improve the test's accuracy further." In November, the Federal Government introduced legal provisions which pave the way towards a more widespread use of rapid antigen testing, including by trained staff in childcare centers and schools**. "The new legal provisions eliminate our dependence on medical staff," says PD Dr. Denkinger. "This makes rapid antigen testing more suited to large-scale roll-out. Research data on self-collected swabs, such as the findings obtained in this study, will be useful to those in charge of finding and implementing new concepts."

Prof. Mockenhaupt adds: "Rapid antigen tests are a significant additional resource to supplement our strained PCR-based testing capacity. Naturally, self-collected swabs and self-administered tests are not without their problems. A test that is administered or interpreted incorrectly, for instance, could result in a false sense of security. On the other hand, a positive rapid antigen test result should always be confirmed by PCR." As a next step, the research team therefore want to study whether rapid antigen tests provide reliable results even when used by lay persons in the absence of professional guidance or supervision.

Researchers from the Microtubule Organization lab, headed by Jens Lüders at IRB Barcelona, and the Macromolecular Complexes in DNA Damage Response Group, led by Oscar Llorca at the Spanish National Cancer Research Centre (CNIO), have achieved the first in vitro reconstitution of the human -tubulin ring complex (γTuRC), responsible for initiating microtubule formation. In addition, they revealed its 3D structure by cryo-electron microscopy. The key to their success lies in the identification of the RUVBL protein complex as an essential γTuRC assembly helper.

Microtubules are a component of the cytoskeleton, which is essential for intracellular transport processes and cell division. Microtubules cannot form spontaneously in cells but require nucleation by the γTuRC. Mutations in γTuRC subunits cause neurodevelopmental defects such as microcephaly and have also been linked to defects in the retina.

"Although the γTuRC was discovered 25 years ago, the field had not been successful in producing it recombinantly in vitro," says co-corresponding author Jens Lüders, "this new achievement opens the door to studies aimed at elucidating the microtubule nucleation mechanism and how it is regulated". It will also allow the study of the mutations found in patients and predictions of their effects, to better understand how they cause disease.

The RUVBL protein complex, essential for the construction of the γTuRC

The difficulty to assemble the γTuRC in vitro is due not only to its complex 3D structure but also to the need of RUVBL for the assembly and formation of the ring-shaped TuRC. "When I started this project I analyzed previously published data, and noticed that a requirement for RUVBL in γTuRC assembly had never been considered before - it was very gratifying to see that this was indeed the key to our success" explains first author Fabian Zimmerman, PhD student in the Microtubule Organization lab at IRB Barcelona.

"Our group has been exploring the function of RUVBL in the assembly of large macromolecular structures relevant to cancer for years. Discovering that RUVBL is also essential for the formation of γTuRC opens new avenues of research to understand how cells build complex functional structures," says co-corresponding author Oscar Llorca.

" γTuRC is a very large structure built by multiple and interconnected subunits. Determining its 3D architecture has been an immense challenge, made possible by advances in cryo-electron microscopy methods that allowed us to observe individual molecules of this complex with extremely high detail ", explains co-first author Marina Serna.