Certain bacteria, known as plant-growth-promoting bacteria (PGPB), can improve plant health or protect them from pathogens and are used commercially to help crops. To further improve agricultural yields, it is helpful to identify factors that can improve PGPB behavior.
Many PGPB form sticky communities of cells, known as biofilms, that help them adhere to plant roots. A group of scientists in North Carolina and Massachusetts were interested in finding other plant-associated bacteria that could help PGPB better adhere to plant roots, with the hope that increasing the number of PGPB cells attached to roots would increase their beneficial activities.
Using a liquid-growth-based method, they identified multiple bacterial strains that increased the adherence of PGPB to plant roots over time. These results indicate that the physical or chemical interactions between these different bacterial species result in better long-term maintenance of PGPB on roots.
“Our results highlight how bacteria can use each other for their own benefit. These findings could be used to create groups of bacteria that are able to work together to better protect crop plants and improve their growth,” said Elizabeth Shank, the senior scientist involved with this research. “The results of this research might also be used to better understand and design microbial treatments that could improve crop yields in agricultural settings.”
To conduct this research, Shank and her colleagues performed a high-throughput screen of bacteria originally obtained from the roots of wild-grown plants, ensuring that identified bacteria might naturally come into contact on the roots of plants in native soil environments. They also looked at how other native microbes might alter the behavior of each PGPB strain, emphasizing the importance of understanding how groups of plant-associated microbes affect plants.
This research specifically focused on a PGPB currently used in agricultural treatments so that their findings related to commercial interventions. According to Shank, “One important impact of our work may be further encouraging agricultural biotechnology companies to consider using groups of multiple bacteria (rather than a single isolate) in their search for better and longer-lasting biological treatments to improve crop yield and help increase food production.”
A fast, green and one-step method for producing porous carbon spheres, which are a vital component for carbon capture technology and for new ways of storing renewable energy, has been developed by Swansea University researchers.
The method produces spheres that have good capacity for carbon capture, and it works effectively at a large scale.
Carbon spheres range in size from nanometers to micrometers. Over the past decade they have begun to play an important role in areas such as energy storage and conversion, catalysis, gas adsorption and storage, drug and enzyme delivery, and water treatment.
They are also at the heart of carbon capture technology, which locks up carbon rather than emitting it into the atmosphere, thereby helping to tackle climate change.
The problem is that existing methods of making carbon spheres have drawbacks. They can be expensive or impractical, or they produce spheres that perform poorly in capturing carbon. Some use biomass, making them more environmentally friendly, but they require a chemical to activate them.
This is where the work of the Swansea team, based in the University’s Energy Safety Research Institute, represents a major advance. It points the way towards a better, cleaner and greener way of producing carbon spheres.
The team adapted an existing method known as CVD – chemical vapour deposition. This involves using heat to apply a coating to a material. Using pyromellitic acid as both carbon and oxygen source, they applied the CVD method at different temperatures, from 600-900 °C. They then studied how efficiently the spheres were capturing CO2 at different pressures and temperatures.
They found that:
800 °C was the optimum temperature for forming carbon spheres
The ultramicropores in the spheres that were produced gave them a high carbon capture capacity at both atmospheric and lower pressures
Specific surface area and total pore volume were influenced by the deposition temperature, leading to an appreciable change in overall carbon dioxide capture capacity
At atmospheric pressure the highest CO2 adsorption capacities, measured in millimolars per gram, for the best carbon spheres, were around 4.0 at 0 °C and 2.9 at 25 °C.
This new approach brings several advantages over existing methods of producing carbon spheres. It is alkali-free and it doesn’t need a catalyst to trigger the shaping of the spheres. It uses a cheap and safe feedstock which is readily available in the market. There is no need for solvents to purify the material. It is also a rapid and safe procedure.
Dr Saeid Khodabakhshi of the Energy Safety Research Institute at Swansea University, who led the research, said:
“Carbon spheres are fast becoming vital products for a green and sustainable future. Our research shows a green and sustainable way of making them.
We demonstrated a safe, clean and rapid way of producing the spheres. Crucially, the micropores in our spheres means they perform very well in capturing carbon. Unlike other CVD methods, our procedure can produce spheres at large scale without relying on hazardous gas and liquid feedstocks.
Carbon spheres are also being examined for potential use in batteries and supercapacitors. So in time, they could become essential to renewable energy storage, just as they already are for carbon capture.”
Researchers at Memorial Sloan Kettering have learned how chromosomal instability allows cancer cells to avoid immune defenses and metastasize (spread). The discovery opens up potential new avenues for treatment.
Cancer cells are known for spreading genetic chaos. As cancer cells divide, DNA segments and even whole chromosomes can be duplicated, mutated, or lost altogether. This is called chromosomal instability, and scientists at Memorial Sloan Kettering have learned that it is associated with cancer’s aggressiveness. The more unstable chromosomes are, the more likely that bits of DNA from these chromosomes will end up where they don’t belong: outside of a cell’s central nucleus and floating in the cytoplasm.
Cells interpret these rogue bits of DNA as evidence of viral invaders, which sets off their internal alarm bells and leads to inflammation. Immune cells travel to the site of the tumor and churn out defensive chemicals. A mystery has been why this immune reaction, triggered by the cancer cells, does not spell their downfall.
“The elephant in the room is that we didn’t really understand how cancer cells were able to survive and thrive in this inflammatory environment,” says Samuel Bakhoum, a physician-scientist at MSK and a member of the Human Oncology and Pathogenesis Program.
“The elephant in the room is that we didn’t really understand how cancer cells were able to survive and thrive in this inflammatory environment.”, Samuel Bakhoum, physician-scientist.
According to a new study from Dr. Bakhoum’s lab published December 28 in the journal Cancer Discovery, the reason has to do, in part, with a molecule sitting on the outside of the cancer cells that destroys the warning signals before they ever reach neighboring immune cells.
The findings help to explain why some tumors do not respond to immunotherapy, and — equally important — suggest ways to sensitize them to immunotherapy.
Detecting Dangerous DNA
The warning system Dr. Bakhoum studies is called cGAS-STING. When DNA from a virus (or an unstable cancer chromosome) lands in a cell’s cytoplasm, cGAS binds to it, forming a compound molecule called cGAMP, which serves as a warning signal. Inside the cell, this warning signal activates an immune response called STING, which addresses the immediate problem of a potential viral invader.
In addition, much of the cGAMP also travels outside the cell where it serves as a warning signal to neighboring immune cells. It activates their STING pathway and unleashes an immune attack against the virally infected cell.
Previous work from the Bakhoum lab had shown that cGAS-STING signaling inside of cancer cells causes them to adopt features of immune cells — in particular, the capacity to crawl and migrate — which aids their ability to metastasize. This provided part of the answer to the question of how cancer cells survive inflammation and aid metastasis in the process. The new research shows how the cancer cells cope with the warning signals that activated cGAS-STING releases into the environment. A scissor-like protein shreds the signals, providing a second way the cells can thwart the threat of immune destruction.
The scissor-like protein that coats cancer cells is called ENPP1. When cGAMP finds its way outside the cell, ENPP1 chops it up and prevents the signal from reaching immune cells. At the same time, this chopping releases an immune-suppressing molecule called adenosine, which also quells inflammation.
Through a battery of experiments conducted in mouse models of breast, lung, and colorectal cancers, Dr. Bakhoum and his colleagues showed that ENPP1 acts like a control switch for immune suppression and metastasis. Turning it on suppresses immune responses and increases metastasis; turning it off enables immune responses and reduces metastasis.
The scientists also looked at ENPP1 in samples of human cancers. ENPP1 expression correlated with both increased metastasis and resistance to immunotherapy.
From a treatment perspective, perhaps the most notable finding of the study is that flipping the ENPP1 switch off could increase the sensitivity of several different cancer types to immunotherapy drugs called checkpoint inhibitors. The researchers showed that this approach was effective in mouse models of cancer.
Several companies — including one that Dr. Bakhoum and colleagues founded — are now developing drugs to inhibit ENPP1 on cancer cells.
Dr. Bakhoum says it’s fortunate that ENPP1 is located on the surface of cancer cells since this makes it an easier target for drugs designed to block it.
It’s also relatively specific. Since most other tissues in a healthy individual are not inflamed, drugs targeting ENPP1 primarily affect cancer.
Finally, targeting ENPP1 undercuts cancer in two separate ways: “You’re simultaneously increasing cGAMP levels outside the cancer cells, which activates STING in neighboring immune cells, while you’re also preventing the production of the immune-suppressive adenosine. So, you’re hitting two birds with one stone,” Dr. Bakhoum explains.
The pace of the research has been incredibly fast, he says. “One of the things I would be really proud of is if this research ends up helping patients soon, given that we only just started this work in 2018.”
He hopes there will be a phase I clinical trial of ENPP1 inhibitors within a year.
This study received financial support from the National Institutes of Health (grants DP5OD026395, K08CA222663, and U54CA225088), the NCI Breast Cancer SPORE (P50CA247749), the Burroughs Wellcome Fund Career Award for Medical Scientists, the Parker Institute for Immunotherapy at MSKCC, the Josie Robertson Foundation, and the MSKCC core grant (P30-CA008748); the Breast Cancer Research Foundation, the Louis V. Gerstner, Jr. Scholars Program, an HICCC core grant (P30CA013696), the Oxford Institute for Radiation Oncology, the Prostate Cancer Foundation, the American Society of Clinical Oncology, the Academy of Medical Sciences, HSC Research Development Division of the Public Health Agency in Northern Ireland and the Friends of the Cancer Centre, Swim Across America, Ludwig Cancer Research, and Nonna’s Garden Foundation. Dr. Bakhoum holds a patent related to some of the work described targeting chromosome instability and the cGAS-STING pathway in advanced cancer. He owns equity in, receives compensation from, and serves as a consultant and on the Scientific Advisory Board and Board of Directors of Volastra Therapeutics Inc. He has also consulted for Sanofi, received sponsored travel from the Prostate Cancer Foundation, and both travel and compensation from Cancer Research UK.
Reference: Jun Li, Mercedes A Duran, Ninjit Dhanota, Walid K. Chatila, Sarah E Bettigole, John Kwon, Roshan K Sriram, Matthew Philip Humphries, Manuel Salto-Tellez, Jacqueline A. James, Matthew G Hanna, Johannes C. Melms, Sreeram Vallabhaneni, Kevin Litchfield, Ieva Usaite, Dhruva Biswas, Rohan Bareja, Hao Wei Li, Maria Laura Martin, Princesca Dorsaint, Julie-Ann Cavallo, Peng Li, Chantal Pauli, Lee Gottesdiener, Benjamin J DiPardo, Travis J Hollmann, Taha Merghoub, Hannah Y Wen, Jorge S. Reis-Filho, Nadeem Riaz, Shin-San Michael Su, Anusha Kalbasi, Neil Vasan, Simon N Powell, Jedd D. Wolchok, Olivier Elemento, Charles Swanton, Alexander N Shoushtari, Eileen E Parkes, Benjamin Izar and Samuel F Bakhoum, “Metastasis and immune evasion from extracellular cGAMP hydrolysis”, Cancer Discovery, 2020. DOI: 10.1158/2159-8290.CD-20-0387 https://cancerdiscovery.aacrjournals.org/content/early/2020/12/23/2159-8290.CD-20-0387
Study led by Singapore clinician-scientists has found a way to classify angiosarcomas into three subtypes, allowing for more targeted treatment, better outcomes for patients and the development of new therapies.
Angiosarcomas are clinically aggressive tumours that are more prevalent in Asian populations.
Study led by Singapore clinician-scientists has found a way to classify angiosarcomas into three subtypes, allowing for more targeted treatment, better outcomes for patients and the development of new therapies.
Findings were published in The Journal of Clinical Investigation in October this year.
A new study led by clinician-scientists from the National Cancer Centre Singapore (NCCS), with collaborators from research institutions worldwide, has found that angiosarcomas have unique genomic and immune profiles which allow them to be classified into three different subtypes. With this new and improved classification system, patients can be treated using a personalised-medicine approach and it will encourage the development of novel treatments.
Angiosarcomas, a type of cancer that forms in the lining of the blood and lymph vessels, are more commonly found in Asia making up 7% of all sarcoma diagnoses. Angiosarcomas are aggressive and can spread to various regions of the body and most often occur on the scalp and face.
For angiosarcomas that have not spread, a combined approach using surgery, radiotherapy and/or chemotherapy is often the course of action for treatment. Once the cancer has metastasised, various chemotherapy treatments are typically administered, which often have poor clinical efficacy and little benefit. As a result, angiosarcomas present a challenge for clinicians and patients because treatment options are limited and prognosis is bleak.
“At NCCS, we treat around 100 patients with sarcomas a year. With a deeper understanding of the tumours, we can better treat these group of patients,” said Clinical Assistant Professor Jason Chan, first author of the study and Consultant Medical Oncologist, Division of Medical Oncology, NCCS.
For the study, 68 patients diagnosed with angiosarcoma at NCCS and Singapore General Hospital between 2000 to 2015 were identified. The research team analysed the tumour samples using multiomic sequencing, NanoString immuno-oncology profiling, and multiplex immunohistochemistry and immunofluorescence.
Multiomic sequencing, which is used to find associations or pinpoint biomarkers in biological entities, like an angiosarcoma, found that 50% of the head and neck angiosarcomas exhibited higher tumour mutation burden (TMB) and UV mutational signatures. This indicated that half of the head and neck angiosarcomas may have developed as a result of UV exposure, and are likely to respond to a type of cancer treatment known as immune checkpoint inhibitors.
NanoString profiling, a technology that profiles gene expression in tumours, revealed that patients with angiosarcomas were grouped into three clusters. Patients in the third cluster had specific enrichment of immune cells and genes involved in immune-related signalling. Tumour inflammation signature (TIS) scores were also highest in this third cluster. Cluster one, like cluster three, was found to be predominantly head and neck angiosarcomas although with a lower inflammation footprint. Cluster two exhibited higher expression of genes that typically promote tumour growth and spread. They were also mainly secondary sarcomas, meaning they had previous exposure to certain environmental or genetic risk factors.
Recent clinical studies have shown that treating tumours with high TMB and TIS scores with immune checkpoint inhibitors showed promising results. By stratifying these 68 angiosarcoma patients, the study results suggest that checkpoint immunotherapy can be used for clusters one and three, while the tumour-promoting genes that are highly expressed in cluster two could be explored as potential treatment targets using targeted therapies.
“Our results are very promising, as they show that we can potentially use existing modes of therapy, like immunotherapy to treat a subset of angiosarcoma patients,” said Clin Asst Prof Chan. “The next step will be to perform further molecular and immunological dissection of angiosarcomas to get more insight into how we can best use precision medicine to target these cancers.”
The findings, published in The Journal of Clinical Investigation in October of this year, is testament that research can directly improve patient care.
“Understanding angiosarcomas will allow oncologists to treat their patients in a more targeted way and it is also a confirmation that NCCS is continuously conducting cutting edge, translational research that has an impact on patients,” said Professor Soo Khee Chee, senior author of the study and Founding Director, NCCS.
The research team plans to further the study by investigating the molecular and genomic profiles of other sarcoma subtypes. This study is part of a plan to investigate rare cancers and establish NCCS as a leading global cancer centre.
National Cancer Centre Singapore (NCCS) provides a holistic and multi-disciplinary approach to cancer treatment and patient care. We see close to 65 per cent of the public sector oncology cases, and they are benefiting from the sub-specialisation of our clinical oncologists.
To deliver among the best in cancer treatment and care, our clinicians work closely with our scientists who conduct robust cutting-edge clinical and translational research programmes which are internationally recognised. NCCS strives to be a global leading cancer centre, and shares its expertise and knowledge by offering training to local and overseas medical professionals.
Researchers from Yokohama National University in Japan have developed a prototype microprocessor using superconductor devices that are about 80 times more energy efficient than the state-of-the-art semiconductor devices found in the microprocessors of today’s high-performance computing systems.
As today’s technologies become more and more integrated in our daily lives, the need for more computational power is ever increasing. Because of this increase, the energy use of that increasing computational power is growing immensely. For example, so much energy is used by modern day data centers that some are built near rivers so that the flowing water can be used to cool the machinery.
“The digital communications infrastructure that supports the Information Age that we live in today currently uses approximately 10% of the global electricity. Studies suggest that in the worst case scenario, if there is no fundamental change in the underlying technology of our communications infrastructure such as the computing hardware in large data centers or the electronics that drive the communication networks, we may see its electricity usage rise to over 50% of the global electricity by 2030,” says Christopher Ayala, an associate professor at Yokohama National University, and lead author of the study.
The team’s research, published in Journal: IEEE Journal of Solid-State Circuits, details an effort to develop a more energy efficient microprocessor architecture using superconductors, devices that are incredibly efficient, but require certain environmental conditions to operate.
To tackle this power problem, the team explored the use of an extremely energy-efficient superconductor digital electronic structure, called the adiabatic quantum-flux-parametron (AQFP), as a building block for ultra-low-power, high-performance microprocessors, and other computing hardware for the next generation of data centers and communication networks.
“In this paper, we wanted to prove that the AQFP is capable of practical energy-efficient high-speed computing, and we did this by developing and successfully demonstrating a prototype 4-bit AQFP microprocessor called MANA (Monolithic Adiabatic iNtegration Architecture), the world’s first adiabatic superconductor microprocessor,” said Ayala.
“The demonstration of our prototype microprocessor shows that the AQFP is capable of all aspects of computing, namely: data processing and data storage. We also show on a separate chip that the data processing part of the microprocessor can operate up to a clock frequency of 2.5 GHz making this on par with today’s computing technologies. We even expect this to increase to 5-10 GHz as we make improvements in our design methodology and our experimental setup,” Ayala said.
However, superconductors require extremely cool temperatures to operate successfully. One would think that if you factor in the cooling required for a superconductor microprocessor, the energy requirement would become undesirable and surpass current day microprocessors. But according to the research team this, surprisingly, was not the case:
“The AQFP is a superconductor electronic device, which means that we need additional power to cool our chips from room temperature down to 4.2 Kelvin to allow the AQFPs to go into the superconducting state. But even when taking this cooling overhead into account, the AQFP is still about 80 times more energy-efficient when compared to the state-of-the-art semiconductor electronic devices found in high-performance computer chips available today.”
Now that the team has proven the concept of this superconductor chip architecture, they plan to optimize the chip and determine the chip’s scalability and speed post optimization.
“We are now working towards making improvements in the technology, including the development of more compact AQFP devices, increasing the operation speed, and increasing the energy-efficiency even further through reversible computation,” Ayala said. “We are also scaling our design approach so that we can fit as many devices as possible in a single chip and operate all of them reliably at high clock frequencies.”
In addition to building standard microprocessors, the team is also interested in examining how AQFPs could assist in other computing applications such as neuromorphic computing hardware for artificial intelligence as well as quantum computing applications.
Reference: C. L. Ayala, T. Tanaka, R. Saito, M. Nozoe, N. Takeuchi and N. Yoshikawa, “MANA: A Monolithic Adiabatic iNtegration Architecture Microprocessor Using 1.4-zJ/op Unshunted Superconductor Josephson Junction Devices,” in IEEE Journal of Solid-State Circuits. https://ieeexplore.ieee.org/document/9295318 doi: 10.1109/JSSC.2020.3041338
Lower stress, depression recalled after using drug, study finds.
A single positive experience on a psychedelic drug may help reduce stress, depression and anxiety symptoms in Black, Indigenous and people of color whose encounters with racism have had lasting harm, a new study suggests.
The participants in the retrospective study reported that their trauma-related symptoms linked to racist acts were lowered in the 30 days after an experience with either psilocybin (Magic Mushrooms), LSD or MDMA (Ecstasy).
“Their experience with psychedelic drugs was so powerful that they could recall and report on changes in symptoms from racial trauma that they had experienced in their lives, and they remembered it having a significant reduction in their mental health problems afterward,” said Alan Davis, co-lead author of the study and an assistant professor of social work at The Ohio State University.
Overall, the study also showed that the more intensely spiritual and insightful the psychedelic experience was, the more significant the recalled decreases in trauma-related symptoms were.
A growing body of research has suggested psychedelics have a place in therapy, especially when administered in a controlled setting. What previous mental health research has generally lacked, Davis noted, is a focus on people of color and on treatment that could specifically address the trauma of chronic exposure to racism.
Davis partnered with co-lead author Monnica Williams, Canada Research Chair in Mental Health Disparities at the University of Ottawa, to conduct the research.
“Currently, there are no empirically supported treatments specifically for racial trauma. This study shows that psychedelics can be an important avenue for healing,” Williams said.
The researchers recruited participants in the United States and Canada using Qualtrics survey research panels, assembling a sample of 313 people who reported they had taken a dose of a psychedelic drug in the past that they believed contributed to “relief from the challenging effects of racial discrimination.” The sample comprised adults who identified as Black, Asian, Hispanic, Native American/Indigenous Canadian, Native Hawaiian and Pacific Islander.
Once enrolled, participants completed questionnaires collecting information on their past experiences with racial trauma, psychedelic use and mental health symptoms, and were asked to recall a memorable psychedelic experience and its short-term and enduring effects. Those experiences had occurred as recently as a few months before the study and as long ago as at least 10 years earlier.
The discrimination they had encountered included unfair treatment by neighbors, teachers and bosses, false accusations of unethical behavior and physical violence. The most commonly reported issues involved feelings of severe anger about being subjected to a racist act and wanting to “tell someone off” for racist behavior, but saying nothing instead.
Researchers asked participants to recall the severity of symptoms of anxiety, depression and stress linked to exposure to racial injustice in the 30 days before and 30 days after the experience with psychedelic drugs. Considering the probability that being subjected to racism is a lifelong problem rather than a single event, the researchers also assessed symptoms characteristic of people suffering from discrimination-related post-traumatic stress disorder (PTSD).
“Not everybody experiences every form of racial trauma, but certainly people of color are experiencing a lot of these different types of discrimination on a regular basis,” said Davis, who also is an adjunct faculty member in the Johns Hopkins University Center for Psychedelic and Consciousness Research. “So in addition to depression and anxiety, we were asking whether participants had symptoms of race-based PTSD.”
Participants were also asked to report on the intensity of three common kinds of experiences people have while under the influence of psychedelic drugs: a mystical, insightful or challenging experience. A mystical experience can feel like a spiritual connection to the divine, an insightful experience increases people’s awareness and understanding about themselvess, and a challenging experience relates to emotional and physical reactions such as anxiety or difficulty breathing.
All participants recalled their anxiety, depression and stress symptoms after the memorable psychedelic experience were lower than they had been before the drug use. The magnitude of the positive effects of the psychedelics influenced their reduction in symptoms.
“What this analysis showed is that a more intense mystical experience and insightful experience, and a less intense challenging experience, is what was related to mental health benefits,” Davis said.
The researchers noted in the paper that the study had limitations because the findings were based on participant recall and the entire sample of recruited research volunteers had reported benefits they associated with their psychedelic experience – meaning it cannot be assumed that psychedelics will help all people of color with racial trauma. Davis and Williams are working on proposals for clinical trials to further investigate the effects of psychedelics on mental health symptoms in specific populations, including Black, Indigenous and people of color.
“This was really the first step in exploring whether people of color are experiencing benefits of psychedelics and, in particular, looking at a relevant feature of their mental health, which is their experience of racial trauma,” Davis said. “This study helps to start that conversation with this emerging treatment paradigm.”
This work was funded by the University of Ottawa, the Canada Research Chairs Program and the National Institutes of Health. Additional co-authors included Yitong Xin of Ohio State’s College of Social Work; Nathan Sepeda of Johns Hopkins; Pamela Grigas and Sinead Sinnott of the University of Connecticut; and Angela Haeny of Yale School of Medicine.
There’s something a little off about our theory of the universe. Almost everything fits, but there’s a fly in the cosmic ointment, a particle of sand in the infinite sandwich. Some scientists think the culprit might be gravity—and that subtle ripples in the fabric of space-time could help us find the missing piece.
A new paper co-authored by a University of Chicago scientist lays out how this might work. Published Dec. 21 in Physical Review D, the method depends on finding such ripples that have been bent by traveling through supermassive black holes or large galaxies on their way to Earth.
The trouble is that something is making the universe not only expand, but expand faster and faster over time—and no one knows what it is. (The search for the exact rate is an ongoing debate in cosmology).
Scientists have proposed all kinds of theories for what the missing piece might be. “Many of these rely on changing the way gravity works over large scales,” said paper co-author Jose María Ezquiaga, a NASA Einstein postdoctoral fellow in the Kavli Institute for Cosmological Physics at the UChicago. “So gravitational waves are the perfect messenger to see these possible modifications of gravity, if they exist.”
Gravitational waves are ripples in the fabric of space-time itself; since 2015, humanity has been able to pick up these ripples using the LIGO observatories. Whenever two massively heavy objects collide elsewhere in the universe, they create a ripple that travels across space, carrying the signature of whatever made it—perhaps two black holes or two neutron stars colliding.
In the paper, Ezquiaga and co-author Miguel Zumalácarregui argue that if such waves hit a supermassive black hole or cluster of galaxies on their way to Earth, the signature of the ripple would change. If there were a difference in gravity compared to Einstein’s theory, the evidence would be embedded in that signature.
For example, one theory for the missing piece of the universe is the existence of an extra particle. Such a particle would, among other effects, generate a kind of background or “medium” around large objects. If a traveling gravitational wave hit a supermassive black hole, it would generate waves that would get mixed up with the gravitational wave itself. Depending on what it encountered, the gravitational wave signature could carry an “echo,” or show up scrambled.
“This is a new way to probe scenarios that couldn’t be tested before,” Ezquiaga said.
Their paper lays out the conditions for how to find such effects in future data. The next LIGO run is scheduled to begin in 2022, with an upgrade to make the detectors even more sensitive than they already are.
“In our last observing run with LIGO, we were seeing a new gravitational wave reading every six days, which is amazing. But in the entire universe, we think they’re actually happening once every five minutes,” Ezquiaga said. “In the next upgrade, we could see so many of those—hundreds of events per year.”
The increased numbers, he said, make it more likely that one or more wave will have traveled through a massive object, and that scientists will be able to analyze them for clues to the missing components.
Zumalácarregui, the other author on the paper, is a scientist at the Max Planck Institute for Gravitational Physics in Germany as well as the Berkeley Center for Cosmological Physics at Lawrence Berkeley National Laboratory and the University of California, Berkeley.
Self-learning algorithms analyze medical imaging data.
Imaging techniques enable a detailed look inside an organism. But interpreting the data is time-consuming and requires a great deal of experience. Artificial neural networks open up new possibilities: They require just seconds to interpret whole-body scans of mice and to segment and depict the organs in colors, instead of in various shades of gray. This facilitates the analysis considerably.
How big is the liver? Does it change if medication is taken? Is the kidney inflamed? Is there a tumor in the brain and did metastases already develop? In order to answer such questions, bioscientists and doctors to date had to screen and interpret a wealth of data.
“The analysis of three-dimensional imaging processes is very complicated,” explains Oliver Schoppe. Together with an interdisciplinary research team, the TUM researcher has now developed self-learning algorithms to in future help analyze bioscientific image data.
At the core of the AIMOS software – the abbreviation stands for AI-based Mouse Organ Segmentation – are artificial neural networks that, like the human brain, are capable of learning. “You used to have to tell computer programs exactly what you wanted them to do,” says Schoppe. “Neural networks don’t need such instructions:” It’s sufficient to train them by presenting a problem and a solution multiple times. Gradually, the algorithms start to recognize the relevant patterns and are able to find the right solutions themselves.”
Training self-learning algorithms
In the AIMOS project, the algorithms were trained with the help of images of mice. The objective was to assign the image points from the 3D whole-body scan to specific organs, such as stomach, kidneys, liver, spleen, or brain. Based on this assignment, the program can then show the exact position and shape.
“We were lucky enough to have access to several hundred image of mice from a different research project, all of which had already been interpreted by two biologists,” recalls Schoppe. The team also had access to fluorescence microscopic 3D scans from the Institute for Tissue Engineering and Regenerative Medicine at the Helmholtz Zentrum München.
Through a special technique, the researchers were able to completely remove the dye from mice that were already deceased. The transparent bodies could be imaged with a microscope step by step and layer for layer. The distances between the measuring points were only six micrometers – which is equivalent to the size of a cell. Biologists had also localized the organs in these datasets.
Artificial intelligence improves accuracy
At the TranslaTUM the information techs presented the data to their new algorithms. And these learned faster than expected, Schoppe reports: “We only needed around ten whole-body scans before the software was able to successfully analyze the image data on its own – and within a matter of seconds. It takes a human hours to do this.”
The team then checked the reliability of the artificial intelligence with the help of 200 further whole-body scans of mice. “The result shows that self-learning algorithms are not only faster at analyzing biological image data than humans, but also more accurate,” sums up Professor Bjoern Menze, head of the Image-Based Biomedical Modeling group at TranslaTUM at the Technical University of Munich.
The intelligent software is to be used in the future in particular in basic research: “Images of mice are vital for, for example, investigating the effects of new medication before they are given to humans. Using self-learning algorithms to analyze image data in the future will save a lot of time in the future,” emphasizes Menze.
Reference: Oliver Schoppe, Chenchen Pan, Javier Coronel, Hongcheng Mai, Zhouyi Rong, Mihail Ivilinov Todorov, Annemarie Müskes, Fernando Navarro, Hongwei Li, Ali Ertürk, Bjoern H. Menze Deep learning-enabled multi-organ segmentation in whole-body mouse scans, nature communications, 6.11.2020 – DOI: 10.1038/s41467-020-19449-7 https://www.nature.com/articles/s41467-020-19449-7#Abs1
Two new studies from the University of Rochester Medical Center (URMC) have uncovered an association between vaping and mental fog. Both adults and kids who vape were more likely to report difficulty concentrating, remembering, or making decisions than their non-vaping, non-smoking peers. It also appeared that kids were more likely to experience mental fog if they started vaping before the age of 14.
While other studies have found an association between vaping and mental impairment in animals, the URMC team is the first to draw this connection in people. Led by Dongmei Li, Ph.D., associate professor in the Clinical and Translational Science Institute at URMC, the team mined data from two major national surveys.
“Our studies add to growing evidence that vaping should not be considered a safe alternative to tobacco smoking,” said study author Li.
The studies, published in the journals Tobacco Induced Diseases and Plos One, analyzed over 18,000 middle and high school student responses to the National Youth Tobacco Survey and more than 886,000 responses to the Behavioral Risk Factor Surveillance System phone survey from U.S. adults. Both surveys ask similar questions about smoking and vaping habits as well as issues with mental function.
Both studies show that people who smoke and vape – regardless of age – were most likely to report struggling with mental function. Behind that group, people who only vape or only smoke reported mental fog at similar rates, which were significantly higher than those reported by people who don’t smoke or vape.
The youth study also found that students who reported starting to vape early – between eight and 13 years of age – were more likely to report difficulty concentrating, remembering, or making decisions than those who started vaping at 14 or older.
“With the recent rise in teen vaping, this is very concerning and suggests that we need to intervene even earlier,” said Li. “Prevention programs that start in middle or high school might actually be too late.”
Adolescence is a critical period for brain development, especially for higher-order mental function, which means tweens and teens may be more susceptible to nicotine-induced brain changes. While e-cigarettes lack many of the dangerous compounds found in tobacco cigarettes, they deliver the same amount – or possibly more – nicotine.
While the URMC studies clearly show an association between vaping and mental function, it’s not clear which causes which. It is possible that nicotine exposure through vaping causes difficulty with mental function. But it is equally possible that people who report mental fog are simply more likely to smoke or vape – possibly to self-medicate.
Li and her team say that further studies that follow kids and adults over time are needed to parse the cause and effect of vaping and mental fog.
In addition to Li, authors of the youth study include Catherine Xie, and Zidian Xie, Ph.D. For the adult study, Li was joined by co-authors Zidian Xie, Ph.D., Deborah J. Ossip, Ph.D. Irfan Rahman, Ph.D., and Richard J. O’Connor, Ph.D. Both studies were funded by the National Cancer Institute and the U.S. Food and Drug Administration’s Center for Tobacco Products.