Earth

ITHACA, N.Y. - A Cornell-led collaboration is flipping the switch on traditional synthetic chemistry by using electricity to drive a new chemical reaction that previously stumped chemists who rely on conventional methods.

This new reaction - detailed in the team's paper, "Dual Electrocatalysis Enables Enantioselective Hydrocyanation of Conjugated Alkenes," published June 29 in Nature Chemistry - could spur the manufacture of a host of new, low-cost drugs.

The project was a collaboration between co-senior authors Song Lin and Robert A. DiStasio Jr., both assistant professors of chemistry and chemical biology in the College of Arts and Sciences.

Lin's lab is exploring the potential applications of electrochemistry, which drives chemical reactions with voltage instead of the reagents favored by traditional organic chemistry. Those reagents can be expensive and difficult to control at larger scales. And while electrochemistry is often employed in battery and energy research, it is less commonly used in chemical synthesis.

Lin has been particularly focused on using electrocatalysis to create chiral molecules - molecules that are non-superimposable mirror images of each other (often referred to as left- and right-handed) and quite prevalent throughout medicinal chemistry. For this project, his group partnered with pharmaceutical company Eli Lilly to identify specific reaction transformations that could be targeted to create low-cost precursors for new drugs.

In this work, Lin and his team developed a catalyst that performs asymmetric catalysis - a way of steering chemical reactions towards a specific chiral product (e.g., production of the right-handed version of a chiral molecule instead of the left-handed one).

"This really allowed us to improve the selectivity of the reaction, so you can get a product pure enough to be used, potentially, for drug discovery purposes," Lin said. "While this work does not necessarily change the way the drugs are manufactured, it does provide us with access to a large variety of analogs."

The researchers were able to combine two different reactions - cobalt-mediated hydrogen-atom transfer and copper-promoted radical cyanation - on an alkene substrate using a dual catalytic strategy.

"We have two different catalysts in the system, and each of them takes on a specific role," Lin said. "Electrochemistry allows us to combine these two chemical systems seamlessly, and power multiple chemical cycles or different oxidation events in the same reaction system."

The reaction that resulted - asymmetric hydrocyanation of alkenes - has eluded organic chemists for decades. Now, by varying the substrate, they can tweak the molecular structure of a commercial drug and create new varieties.

To better understand the mechanism behind this long-sought reaction, Lin turned to DiStasio, whose lab specializes in theoretical chemistry. Particularly relevant is the work DiStasio and his group have done describing and understanding the non-bonded (or non-covalent) interactions that occur between molecules.

"After performing a number of detailed quantum mechanical calculations on this system, it became clear to us that the copper catalyst has a rather interesting and dichotomous nature," DiStasio said. "By combining both attractive and repulsive non-covalent interactions, this catalyst enables a very difficult, yet tremendously useful, chemical reaction."

New research from the Francis Crick Institute has found how the malaria parasite protects itself from toxic compounds in red blood cells.

Malaria causes around 400,000 deaths globally each year. It is caused by Plasmodium parasites which are transmitted by mosquitoes and grow in a person's blood stream.

In their study, published in Proceedings of the National Academy of Sciences USA, Crick researchers together with colleagues from Germany and Switzerland identified a protein used by the malaria parasite to protect itself from a toxic compound in red blood cells. They hope this could lead to the development of drugs that block this process.

When the malaria parasite enters a red blood cell it digests haemoglobin, leading to the release of a compound called haem, which is toxic to the parasite if it is left loose inside the cell.

The researchers found that to overcome this, the parasite uses a protein, called PV5, to control a process where free haem molecules are joined together into insoluble crystals which are not harmful. This is vital to the survival of the malaria parasite.

When the researchers blocked this protein in the lab, they found that the human-infecting malaria parasite made fewer and highly misshapen crystals. When the protein was blocked in mice that had been infected with a rodent strain of malaria, the parasite became more sensitive to several antimalarial drugs.

Joachim Matz, lead author and postdoctoral research fellow in the Malaria Biochemistry Laboratory at the Crick says: "The importance of haem crystallisation to malaria has been understood for a while, but what has been missing is knowledge about how this process is controlled by the parasite. By identifying a protein that is key to this process, we've opened the door to potential new treatments which can stop malaria in its tracks".

Mike Blackman, author and group leader of the Malaria Biochemistry Laboratory at the Crick says: "The issue of malaria developing resistance to antimalarial drugs is of grave concern. The parasite is already resistant to many drugs and this underpins the need to find new treatments."

"We hope that an improved understanding of the mechanisms at play during this haem crystallisation process will provide valuable insights for the development of future drugs."

The researchers will continue to study the role of PV5 during haem crystallisation, with a view to identify the exact mechanism behind this process.

LAWRENCE -- Playing "hard-to-get" is an age-old gambit for dating and mating, familiar to moviegoers, readers of literature and any admirer who's ever been "left on read."

Research just published in the peer-reviewed journal Personality and Individual Differences looks at the psychological underpinnings of making yourself seem more desirable by withholding obvious signs of romantic interest.

"If you think about things like 'breadcrumbing' or 'benching' -- you're letting people think you're interested in them, then pulling away or keeping things as they are without moving the relationship forward," said Omri Gillath, professor of psychology at the University of Kansas, who co-wrote the paper. "You're not escalating or de-escalating the effort. For instance, you're sitting there and playing with your phone -- phubbing -- not paying full attention to the other person and making them struggle to get your attention. It's sending a double message. On the one hand, you're saying you're interested. But on the other hand you're saying, 'You'll have to work hard to actually get my full attention.'"

Gillath and Jeffery Bowen of Johns Hopkins University looked to discover the associations among romantic aloofness, gender and "attachment style," the psychological term for people's way of thinking, feeling and behaving in close relationships.

Attachment style, usually formed in childhood, falls into the primary categories of secure or insecure (people with an insecure attachment style are usually classified as anxious or avoidant). Overall, the researchers found that women and people with insecure attachment styles tended to play hard-to-get more.

"Hard-to-get behaviors seem to serve as strategies to self-protect and manage potential partners' behaviors," Gillath said. "Women, as we expected, are playing hard-to-get more, and men are pursuing them. Avoidant people tend to be playing hard-to-get, and anxious people are pursuing them. The nice thing is it's compatible. If you're secure about yourself and about others loving you, you're less likely to get involved in such game-playing -- and you're not playing hard-to-get or pursuing people that are playing hard-to-get. But if you're insecure you're more likely to use these strategies, playing and pursuing, and it's serving a role for both sides."

Across four studies involving over 900 participants, the authors examined links between attachment style and hard-to-get strategies. Among their findings:

Attachment style predicts and shapes hard-to-get behavior, particularly among insecurely attached individuals.

People higher on attachment avoidance and women (vs. men) reported playing hard-to-get more.

People higher on attachment anxiety and men (vs. women) reported more pursuing of hard-to-get others.

When researchers nudged (or primed) thoughts of attachment insecurity, they found primed avoidance led to a greater likelihood of playing hard-to-get among avoidant heterosexual men. Primed anxiety led to greater reported likelihood of pursuing hard-to-get targets overall.

While many people might be using these strategies (playing and pursuing), their reasons for doing so might be different (control, self-protection, partner selection, etc.)

According to the authors, their study sheds light on how people with avoidant and anxious attachment styles manage their psychological vulnerabilities. Put another way, our behavior in trying to find mates and partners is rooted in early life experiences.

For people with insecure attachment styles, Gillath said playing hard-to-get, or chasing an aloof potential mate, are efficient approaches for securing intimacy, romantic relationships and sex.

"We're not saying it's good or it's bad, but for some people these strategies are working," he said. "It helps people create relationships and get partners they want. But who's doing it and what are the outcomes? These people are usually insecure people -- and their relationships are often ones that won't last long or will be dissatisfying."

For other people, playing hard-to-get is less a romantic strategy and more of a survival instinct.

"Sometimes, it's not so much about the relationship but about helping people to stay in control," Gillath said. "Some people are behaving in such a way because they're terrified. They can't trust anyone -- and they're doing whatever they can to protect themselves from getting hurt again. So, for them, it's not 'playing.' This is not a game for them but a way to protect themselves and to verify people out there are serious and are going to be reliable mates."

The KU researcher said "playing hard-to-get" is one aspect of the psychological power dynamics that define many human relationships, whether they're romantic or not.

"Any relationship where we have two sides involved is going to have some push and pull," Gillath said. "There are relationships where one side wants it more and the other side wants it less. The side that is less invested has more power. If you really need my friendship and I have other friends, I'm going to have more power and control in the friendship and could potentially play hard-to-get. The person who's more desperate is likely to have less control and less power and likely to pursue more."

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide, affecting an estimated one-quarter of the global population. It is a progressive condition that, in worst cases, can lead to cirrhosis, liver cancer, liver failure and death.

In a new paper published online June 30, 2020 in Cell Metabolism, a team of scientists, led by researchers at University of California San Diego School of Medicine, report that stool microbiomes -- the collection of microorganisms found in fecal matter and in the gastrointestinal tract -- of NAFLD patients are distinct enough to potentially be used to accurately predict which persons with NAFLD are at greatest risk for having cirrhosis -- the late-stage, irreversible scarring of the liver that often requires eventual organ transplantation.

"The findings represent the possibility of creating an accurate, stool microbiome-based, non-invasive test to identify patients at greatest risk for cirrhosis," said senior author Rohit Loomba, MD, professor of medicine in the Division of Gastroenterology at UC San Diego School of Medicine and director of its NAFLD Research Center. "Such a diagnostic tool is urgently needed."

Loomba said a novel aspect of the study is the external validation of gut microbiome signatures of cirrhosis in participant cohorts from China and Italy. "This is one of the first studies to show such a robust external validation of a gut microbiome-based signature across ethnicities and geographically distinct cohorts.

The work builds upon previous published research in 2017 and 2019 by Loomba and colleagues.

A link between NAFLD and the gut microbiome is well-documented, but specifics were scant and it has not been clear that discrete metagenomics and metabolomics signatures might be used to detect and predict cirrhosis. In the latest study, researchers compared the stool microbiomes of 163 participants encompassing patients with NAFLD-cirrhosis, their first-degree relatives and control-patients without NAFLD.

Combining metagenomics signatures with participants' ages and serum albumin (an abundant blood protein produced in the liver) levels, the scientists were able to accurately distinguish cirrhosis in participants differing by cause of disease and geography.

The next step, said Loomba, is to establish causality of these gut microbial species or their metabolites in causing cirrhosis, and whether this test can be used and scaled up for clinical use.

Over the past 150 years, global warming has more than undone the global cooling that occurred over the past six millennia, according to a major study published June 30 in Nature Research's Scientific Data, "Holocene global mean surface temperature, a multi-method reconstruction approach." The findings show that the millennial-scale global cooling began approximately 6,500 years ago when the long-term average global temperature topped out at around 0.7°C warmer than the mid-19th century. Since then, accelerating greenhouse gas emissions have contributed to global average temperatures that are now surpassing 1°C above the mid-19th century.

Four researchers of Northern Arizona University's School of Earth and Sustainability (SES) led the study, with Regents' professor Darrell Kaufman as lead author and associate professor Nicholas McKay as co-author, along with assistant research professors Cody Routson and Michael Erb. The team worked in collaboration with scientists from research institutions all over the world to reconstruct the global average temperature over the Holocene Epoch--the period following the Ice Age and beginning about 12,000 years ago.

"Before global warming, there was global cooling," said Kaufman. "Previous work has shown convincingly that the world naturally and slowly cooled for at least 1,000 years prior to the middle of the 19th century, when the global average temperature reversed course along with the build-up of greenhouse gases. This study, based on a major new compilation of previously published paleoclimate data, combined with new statistical analyses, shows more confidently than ever that the millennial-scale global cooling began approximately 6,500 years ago."

Earlier this year, an international group of 93 paleoclimate scientists from 23 countries--also led by Kaufman, McKay, Routson and Erb--published the most comprehensive set of paleoclimate data ever compiled for the past 12,000 years, compressing 1,319 data records based on samples taken from 679 sites globally. At each site, researchers analyzed ecological, geochemical and biophysical evidence from both marine and terrestrial archives, such as lake deposits, marine sediments, peat and glacier ice, to infer past temperature changes. Countless scientists working around the world over many decades conducted the basic research contributing to the global database.

"The rate of cooling that followed the peak warmth was subtle, only around 0.1°C per 1,000 years. This cooling seems to be driven by slow cycles in the Earth's orbit, which reduced the amount of summer sunlight in the Northern Hemisphere, culminating in the 'Little Ice Age' of recent centuries," said Erb, who analyzed the temperature reconstructions.

Since the mid-19th century, global warming has climbed to about 1°C, suggesting that the global average temperature of the last decade (2010-2019) was warmer than anytime during the present post-glacial period.

McKay, who developed some of the statistical approaches to synthesizing data from around the world, notes that individual decades are not resolved in the 12,000-year-long temperature reconstruction, making it difficult to compare it with any recent decade. "On the other hand, this past decade was likely cooler than what the average temperatures will be for the rest of this century and beyond, which are very likely to continue to exceed 1°C above pre-industrial temperatures," McKay said.

"It's possible," Kaufman said, "that the last time the sustained average global temperature was 1°C above the 19th century was prior to the last Ice Age, back around 125,000 years ago when sea level was around 20 feet higher than today."

"Investigating the patterns of natural temperature changes over space and time helps us understand and quantify the processes that cause climate to change, which is important as we prepare for the full range of future climate changes due to both human and natural causes," said Routson. He used an earlier version of the database to link Arctic warming to a reduction in precipitation at mid latitudes (see related article).

"Our future climate will largely depend on the influence of human factors, especially the build-up of greenhouse gases. However, future climate will also be influenced by natural factors, and it will be complicated by the natural variability within the climate system. Future projections of climate change will be improved by better accounting for both anthropogenic and natural factors," he said.

The reconstruction of past global temperature is the outgrowth of several NAU research projects aimed at understanding the causes and effects of natural climate variability, work that was funded through more than $1.2 million in grants from the National Science Foundation. The team was recently awarded another $678,000 in grants from the NSF for related work extending through 2023.

In a study published recently in Ecology and Evolution, an international team of researchers focused on what can happen to ocean ecosystems when fishing pressure increases or decreases, and how this differs between tropical to temperate marine ecosystems. The team, led by Elizabeth Madin, researcher at the Hawai'i Institute of Marine Biology (HIMB) in the University of Hawai'i (UH) at Mānoa School of Ocean and Earth Science and Technology (SOEST), found ecosystems do not respond universally to fishing.

There has been much debate about the degree to which ocean ecosystems are impacted by fishing, also termed "top-down forcing" because such changes occur when predators at the top of the food web are removed, versus the availability of nutrients and other resources in an ecosystem, termed "bottom-up forcing".

"Examples from a variety of marine systems of exploitation-induced, top-down forcing have led to a general view that human-induced predator perturbations can disrupt entire marine food webs, yet other studies that have found no such evidence provide a counterpoint," said Madin.

Madin worked with an amazing team of marine ecologists from all over the world, particularly those from the Australian Institute of Marine Science (AIMS) and the University of Tasmania (UTas). Using time?series data for 104 reef communities spanning tropical to temperate Australia from 1992 to 2013, they aimed to quantify relationships among populations of predators, prey, and algae at the base of the food web; latitude; and exploitation status over a continental scale.

As expected, no-take marine reserves--where fishing is prohibited--led to long-term increases in predator population sizes.

"This is good news for fishers, because as populations increase, the fish don't recognize the reserve boundaries and are likely to 'spill over' into adjacent areas where fishing is allowed, creating a kind of insurance policy whereby marine reserves ensure the ability of fishers to catch fish into the future," said Madin.

Surprisingly though, the team found that in the tropics, the system tends to be driven predominantly by bottom-up forcing, whereas colder, temperate ecosystems are more driven by top-down forcing.

"I assumed at the start of the project that in places where fishing pressure was high and predators were depleted, we would see consequent increases in the population sizes of the predators' prey species, and the decreases in the prey's prey species," explained Madin. "However, in the tropical part of our study system, that is, Australia's Great Barrier Reef, this simply wasn't the case. This result had me scratching my head for quite some time, until I realized that this type of domino effect, called a trophic cascade, is simply a real, but rare, phenomenon in the tropics."

These kinds of continent-scale analyses are only possible with large, long-term datasets. 

This study relied on data from the AIMS long-term coral reef monitoring program and the UTas Australian Temperate Reef Collaboration--creating one enormous, continental-scale reef dataset.

"Only by looking at the very big picture, it turned out, were we able to find these trends," said Madin. 

Predator loss is now a globally pervasive phenomenon that touches nearly every marine ecosystem on the planet. Ecosystem destabilization is a widely-assumed consequence of predator loss. However, the extent to which top-down versus bottom-up forcing predominates in different types of marine systems is not definitively understood.
 

"Understanding how our fisheries are likely to impact other parts of the food web is important in making the best possible decisions in terms of how we manage our fisheries," said Madin. "By understanding how coral reef food webs are likely to respond to fishing pressure, or conversely to marine reserves, we can make more informed decisions about how much fishing our reefs can safely handle. Likewise, this knowledge gives us a better idea of what will happen when we create marine reserves designed to serve as an insurance policy so communities can continue to catch fish long into the future." 
 

Madin was recently granted a prestigious CAREER award, offered by the National Science Foundation in support of early-career faculty who have the potential to serve as academic role models in research and education. With the funding, Madin will focus on understanding what food web interactions can reveal about how coral reefs worldwide are faring as fishing pressure increases or decreases. Interwoven with this research program will be an education and outreach program to help students develop cutting-edge technological skills relevant to marine research and help students and the public understand the importance of coral reefs to Hawai'i through visual arts, specifically, the creation of reef-inspired public murals. 

Parents and clinicians need to be aware in looking for symptoms of multiple inflammatory syndrome (MIS-C) in children who have been diagnosed or exposed to COVID-19, according to two Rutgers researchers who were among the leaders of the first nationwide study of the disease, published in the New England Journal of Medicine. MIS-C is defined as an inflammation impacting two or more organ systems within the body, and appears to be a late complication following an infection or exposure to COVID-19.

Funded by the U.S. Centers for Disease Control and Prevention, the study presents 186 cases of pediatric MIS-C from around the country and another 27 from New York State, from March 16 to May 20. The article describes clinical characteristics, treatments and outcomes of MIS-C.

"The study highlights our ever-changing understanding of COVID-19 in children," said Professor Lawrence C. Kleinman, chair for academic development and chief of the Division of Population Health, Quality, and Implementation Sciences in the Department of Pediatrics at the Rutgers Robert Wood Johnson Medical School and Bristol-Myers-Squibb Children's Hospital. "We have moved from thinking that COVID-19 spares children to understanding that children can get very sick. Children play an important role in the pandemic."

"This article describes how even in the absence of strong prior evidence, doctors mindfully identified and repurposed potential therapies to positive effect," added Steven Horwitz, assistant professor of pediatric critical care at the Rutgers Robert Wood Johnson Medical School. "Individuals with MIS-C can get very sick and many need therapies to support their breathing and their heart function. Still, with proper identification and treatment, thankfully the majority of these children and adolescents get better and many do so very quickly."

Researchers found symptoms of the disease typically appear two to four weeks after the onset of COVID-19 or after exposure to the SARS-CoV2 virus that causes COVID-19. Among the children confirmed to have had COVID-19, the median time in which inflammatory symptoms appeared was 25 days. More than two-thirds of the children and adolescents were healthy before their experience with SARS-CoV2, and nearly four in five hospitalized with MIS-C required ICU care. More than two-thirds of the children in the study were over the age of five. As of May 20, 70 percent had been discharged, 28 percent were still hospitalized and 2 percent had died.

With its frequent involvement of the heart and heart vessels, MIS-C initially came to attention as an illness similar to Kawasaki disease. The NEJM study illustrates that these are distinct syndromes with MIS-C having more frequent and severe involvement of the heart and more typically occurring in an older population. MIS-C most frequently involves the digestive system.

The study was based out of a collaborative network based in Boston Children's Hospital. The Rutgers team helped to lead expansion to include many more cases from the original hotspots in the New York and New Jersey region. While the disease is defined as involvement of at least two organ systems, more than two-thirds of cases involved four or more organ systems.

Due to the wide range of symptoms with the disease, including fever, fatigue, rash, shortness of breath, and abdominal pain, parents should seek medical care for children and adolescents who were exposed to COVID-19 and develop these symptoms.

Researchers stress that the long-term effects of the syndrome are still unknown, as is the possibility that MIS-C exists in a milder form impacting a single organ system, or that does not require hospitalization. They also emphasized the need for clinicians to work together both clinically and in research to expand available evidence to inform better diagnosis and treatment for children. They also encouraged other physicians who may see patients for the first time with symptoms related to MIS-C, to reach out to experienced clinicians for assistance with diagnosis and treatment protocols.

Hospitals and doctors nationwide are collaborating to continue developing broad protocols for treatment to improve recovery outcomes for our patients and create effective assessments to save lives.

New research from NUI Galway and the University of Limerick has for the first time quantified the volume of plastic from European countries (EU, UK, Switzerland and Norway) that contributes to ocean littering from exported recycling.

While European countries have developed world-leading waste management infrastructure, 46% of European separated plastic waste is exported outside the country of origin. A large share of this plastic is transported thousands of kilometres to countries with poor waste management practices, largely located in Southeast Asia. Once in these countries, a large share of the waste is rejected from recycling streams into overstretched local waste management systems that have been found to contribute significantly to ocean littering.

This new research, published in the scientific journal Environment International, estimated the best-case, average, and worst-case scenarios of ocean debris pathways from exported recycling in 2017. The results estimated a range between 32,115 - 180,558 tonnes, or 1 - 7% of all exported European polyethylene, which ended up in the ocean. Polyethylene is one of the most common types of plastic in Europe, and the results showed that countries such as the UK, Slovenia, and Italy are exporting a higher share of plastic outside of Europe and see a higher share of their recyclable plastic waste end up as ocean debris.

Speaking today, George Bishop, lead author of the study said: "The results indicate an important and previously undocumented pathway of plastic debris entering the oceans, which will have considerable environmental and social impacts on marine ecosystems and coastal communities."

Using detailed international trade data and data on waste management in destination countries, the study modelled the fate of all polyethylene exported for recycling from Europe, accounting for different fates ranging from successful conversion into recycled resins, or ending up as landfill, incineration, or ocean debris.

Dr David Styles, a lecturer at the University of Limerick and co-author, explains, "Given that such a large share of waste destined for recycling is exported, with poor downstream traceability, this study suggests that 'true' recycling rates may deviate significantly from rates reported by municipalities and countries where the waste originates. In fact, our study found that up to 31% of the exported plastic wasn't actually recycled at all".

The study was part of the Science Foundation Ireland funded, 'Innovative Energy Technologies for Bioenergy, Biofuels and a Sustainable Irish Bioeconomy: IETSBIO3' led by Professor Piet Lens, Established Professor of New Energy Technologies at the National University of Ireland, Galway.

Professor Lens added: "To successfully move towards a more circular economy, European municipalities and waste management companies need to be held accountable for the final fate of "recycled" waste. Our study highlights the lack of available data on plastic waste and the need to consider extended audit trails, or "on-shoring" of recycling activities as part of emerging regulations around trade in plastic waste."

The authors caution that these findings should not discourage people to recycle as it remains the best waste management treatment, environmentally speaking. However, there is considerable work to be done to improve aspects of these plastic recycling chains, to reduce the 'leakage' of these systems.

New Curtin University-led research has uncovered how rocks sourced from the Earth's mantle are linked to the formation and breakup of supercontinents and super oceans over the past 700 million years, suggesting that the Earth is made up of two distinct 'faces'.

The research, published in the leading Journal Nature Geoscience, examined the chemical and isotopic 'make-up' of rocks sourced from thousands of kilometres below the surface to better understand how the Earth's mantle responds to plate movements that occur near its surface.

Lead author Dr Luc-Serge Doucet, from the Earth Dynamics Research Group in Curtin's School of Earth and Planetary Sciences, said the Earth's mantle is currently divided into two main domains, African and Pacific, but little is known about their formation and history and they are commonly assumed to be chemically the same.

"Our team used trace metals such as lead, strontium, and neodymium, from hotspot volcanic islands including the Hawaiian islands in the Pacific Ocean and the La Reunion island in the Indian Ocean, to examine whether these two domains have the same chemical 'make-up'," Dr Doucet said.

"We found that the African domain was 'enriched' by subducted continental materials, which was linked to the assembly and breakup of the supercontinent Pangaea, whereas no such feature was found in the Pacific domain."

The team found that the contents of the two mantle domains are not exactly the same as previously thought. Instead, the Earth appears to have two chemically distinct hemispheric 'faces', with the Pacific ring of fire being the surface expression of the boundary between the two.

Co-author John Curtin Distinguished Professor Zheng Xiang Li, head of the Earth Dynamics Research Group, said the two chemically distinct hemispheres discovered by the team can best be explained by the distinct evolutionary histories of the two mantle domains during the Rodinia to Pangaea supercontinent cycles.

"We found that the African mantle domain contains continental materials, which were brought down by the subduction system for at least the past 600 million years. However, the Pacific mantle domain has been protected from the infiltration of such materials," Professor Li said.

"Our research findings are significant as they showcase a dynamic relationship between plate tectonic processes that operate near the surface and the formation and evolution of Earth's deep mantle structures.

"The work helps us to understand what drives plate tectonics and the formation and reservation of global geotectonic features such as the Pacific ring of fire. The dynamic and interactive nature of the entire Earth system has important implications on the formation of Earth resources, the evolution of Earth environment, and even the evolution of life."

The cover for issue 26 of Oncotarget features Figure 6, "Mislocalization of IQGAP1-BRCA1 in human TNBC tumors phenocopies the dominant mutants and the TNBC cells," by Osman, et al. and reported that IQGAP1 is a signaling scaffold implicated in TNBC, but its mechanism is unknown.

Genetic mutant analyses suggest that phosphorylation cycling of IQGAP1 is important to its subcellular localization and centrosome-nuclear shuttling of BRCA1; dysfunction of this process defines two alternate mechanisms associated with cell proliferation.

TNBC cell lines and patient tumor tissues differentially phenocopy these mechanisms supporting the clinical existence of molecularly distinct variants of TNBC defined by IQGAP1 pathways.

The authors discuss a model in which IQGAP1 modulates centrosome-nuclear crosstalk to regulate cell division and imparts on cancer.

These findings have implications on cancer racial disparities and can provide molecular tools for classification of TNBC, presenting IQGAP1 as a common target amenable to personalized medicine

Dr. Mahasin A. Osman from The Department of Medicine, Division of Oncology, Health Sciences Campus at The University of Toledo as well as The Department of Molecular Pharmacology, Physiology and Biotechnology, Division of Biology and Medicine at Warren Alpert Medical School of Brown University said, “The triple-negative breast cancer (TNBC) is a highly heterogeneous group of diseases defined by absence of expression of growth factor and hormonal receptors, and thus it is highly lethal due to lack of diagnostic markers and therapeutic targets.”

In vitro depletion of BRCA1 results in amplified centrosomes, a phenotype observed in early-stage tumors, including breast cancer, but how might wild type BRCA1 protein control centrosome amplification is unclear.

While increased centrosome size resulting from PCM expansion has been reported as abnormality in human tumors, increased centrosome number is observed in 20–30% of tumors that overexpress oncogenes or lack tumor suppressors like BRCA1.

Centrosome amplification has been associated with high-grade tumors and poor prognosis and was suggested as a biomarker for advanced cancer.

Expression of dominant active mutants of IQGAP1 associates with amplified centrosomes while the expression of dominant-negative mutants associates with increased centrosome size.

The authors discuss a model whereby IQGAP1 acts as a signaling scaffold in the centrosome and influences centrosome protein transport, dysfunction of which underlie centrosome aberrations in cancer thereby presenting IQGAP1 as a common target in variants of TNBC, amenable to personalized medicine.

The Rotelli Research Team concluded in their Oncotarget Research Paper that taken together, the findings of this study underscore the importance of the delicate balance of expression, localization and/or modification of IQGAP1-BRCA1 and centrosome proteins in cell homeostasis and support that IQGAP1 influences BRCA1 transport or anchorage.

IQGAP1 may serve as a regulatory scaffold for BRCA1 and other centrosomal proteins to regulate their stability or transport between the nucleus and the centrosome, a mechanism by which it modulates nuclear-centrosome crosstalk during the cell cycle and thus regulates cell proliferation.

Furthermore, as IQGAP1 has been implicated in various carcinomas, the mechanisms discussed here likely apply to a wide range of carcinoma, thus presenting IQGAP1 as a non-organ-specific clinical target amenable to precision medicine.

"The mechanisms discussed here likely apply to a wide range of carcinoma, thus presenting IQGAP1 as a non-organ-specific clinical target amenable to precision medicine."

Gliomas with mutations in what are called the isocitrate dehydrogenase (IDH) genes are the most common brain tumors diagnosed in younger adults aged 18 to 45 years. Patients can benefit from aggressive surgery, along with radiation and chemotherapy treatments, but these therapies are not curative in many cases.

Now a team led by investigators at Massachusetts General Hospital has uncovered a potentially promising strategy to target these tumors and improve treatment. The findings are published in Cancer Discovery, a journal of the American Association for Cancer Research.

Prior work by the group, led by Mass General's Daniel Cahill, MD, PhD, Hiroaki Wakimoto, MD, PhD, and Julie Miller, MD, PhD, revealed that IDH mutant gliomas have a metabolic weakness making them especially susceptible to treatments that lower levels of NAD+, a ubiquitous and vital metabolic molecule commonly thought of as the "currency of metabolism" in cells.

Also, previous work by other researchers found that chemotherapy activates an enzyme that stimulates NAD+ molecules to join together to make poly(ADP-ribose), or PAR, a key DNA damage signal. This PAR signal is a known susceptibility in IDH mutant gliomas.

Researchers also discovered that activation of the enzyme by chemotherapy causes available NAD+ to be critically depleted for the production of PAR in IDH mutant glioma cells, but not normal cells.

These findings indicated that maintaining high PAR levels (and low NAD+ levels), in combination with chemotherapy, may uniquely target IDH mutant glioma cells. Considering this, Hiroaki Nagashima, MD, PhD, research fellow and lead author, devised a new treatment strategy and tested it in tumor cells and animal models.

"We found that maximum effectiveness was achieved by combining two agents: temozolomide, the chemotherapy most commonly used to treat patients with IDH mutant gliomas, with a drug that blocks PAR breakdown, known as a PAR glycohydrolase inhibitor," said Dr. Cahill, a Neurosurgical Oncologist at Mass General and an Associate Professor of Neurosurgery at Harvard Medical School.

"We showed, for the first time, that PAR glycohydrolase inhibitors can be used to enhance the effectiveness of chemotherapy in tumors with metabolic weaknesses in the NAD+ pathway," said Dr. Wakimoto, an Associate Professor of Neurosurgery at Harvard Medical School.

Dr. Miller, an Instructor in Neurology and a Neuro-Oncologist at Mass General who treats patients with IDH mutant glioma, noted that PAR glycohydrolase inhibitors are a newly-emerging class of drugs. "The long-term significance is that, based on our findings, they could be tested in individuals with IDH mutant gliomas, with a goal of hopefully improving outcomes in these patients," she said.

WOODS HOLE, Mass. - Corals are "part animal, part plant, and part rock - and difficult to figure out, despite being studied for centuries," says Philippe Laissue of University of Essex, a Whitman Scientist at the Marine Biological Laboratory. Many corals are sensitive to bright light, so capturing their dynamics with traditional microscopes is a challenge.

To work around their photosensitivity, Laissue developed a custom light-sheet microscope (the L-SPI) that allows gentle, non-invasive observation of corals and their polyps in detail over eight continuous hours, at high resolution. He and his colleagues, including MBL Associate Scientist and coral biologist Loretta Roberson, published their findings this week in Scientific Reports.

A video explainer of the research is here.

Coral reefs, made up of millions of tiny units called polyps, are extremely important ecosystems, both for marine life and for humans. They harbor thousands of marine species, providing food and economic support for hundreds of millions of people. They also protect coasts from waves and floods, and hold great potential for pharmaceutical and biotechnological discovery.

But more than half of the world's coral reefs are in severe decline. Climate change and other human influences are gravely threatening their survival. As ocean temperatures rise, coral bleaching is afflicting reefs worldwide. In coral bleaching, corals expel their symbiotic algae and become more susceptible to death.

"The L-SPI opens a window on the interactions and relationship between the coral host, the symbiotic algae living in their tissues, and the calcium carbonate skeleton they build in real time," Roberson says. "We can now track the fate of the algae during [coral] bleaching as well as during initiation of the symbiosis."

Roberson is also using Laissue's imaging technology to measure damage to corals from "bioeroders" - biological agents like algae and sponges that break down a coral's skeleton, a problem exacerbated by ocean acidification and increasing water temperatures.

High-pressure materials science has taken off over the last couple of decades with advances in previously difficult experimental techniques and from technologies such as diamond anvils, which squeeze samples of materials between two diamonds at pressures up to millions of times greater than that at the Earth's surface.

The field uses these extreme conditions that mirror the deep interior of planets to discover new materials, to modify the properties of known materials in potentially useful and even exotic ways, and to test their concepts about how materials work or to simulate what it is like inside the Earth.

Meanwhile, perovskite is both the most abundant mineral in the Earth's mantle (composed of calcium titanate, CaTiO3) and the name of any material that has the same, special crystal structure as this mineral. Perovskite structures are of great interest to materials scientists due to multiple interesting properties that are important in a range of microelectronics, telecommunications and clean-energy applications.

Using advanced high-pressure techniques, Professor Changqing Jin, who leads the research team at The Institute of Physics, Chinese Academy of Sciences, also adjunct to University of Chinese Academy of Sciences(UCAS) has been fabricating many new materials with perovskite structures and novel functionality for some time. Recently his lab has been synthesizing a new type of perovskite compound, called the 'double perovskites,' which has twice the 'unit cell,' or smallest possible building block of a crystal, of regular perovskites.

The findings were published in the peer-reviewed journal Angewandte Chemie published by Wiley.

The study details how the researchers exposed their latest double perovskite, composed of yttrium, cobalt, iridium and oxygen atoms (Y2CoIrO6), to varying levels of extreme pressure, and what happened when they did so.

For most materials, an increase in pressure allows for an increase in the number of atoms that can gather immediately around a central atom in a crystal (called the coordination number.

But the new double perovskite, Y2CoIrO6, did not adhere to the traditional theories that crystal structure order tends to increase with the increase of pressure.

Instead, when synthesized at ambient pressure, Y2CoIrO6 is highly ordered, but surprisingly when synthesized at 6 gigapascals (GPa, or roughly 60,000 times standard atmospheric pressure), while the unit cell did get smaller, now there was only partial ordering.

Then at 15 GPa, the researchers found disordering. Increasing pressure had inverted the normal order-to-disorder sequence that the researchers expected. In addition, the magnetic properties of the material changed

"Curiously, 15 GPa is also the pressure that you find at the boundary region between the upper and lower mantle deep in the Earth," said Zheng Deng, another member of the team. "This is precisely where many perovskite materials form."

Gaining further insight into this unexpected pressure-dependent order-disorder transition could help scientists to better understand the properties of minerals that make up the mantle and deeper interior of our planet

"This violates our intuition about chemistry at high pressures," Deng continued. "It means we're going to have to entirely reconsider the effects of pressure in solid-state sciences"

The discovery could permit design and synthesis of useful new materials at high pressures with attributes that would otherwise be hard to achieve under normal
conditions.

A challenge to creating fusion energy on Earth is trapping the charged gas known as plasma that fuels fusion reactions within a strong magnetic field and keeping the plasma as hot and dense as possible for as long as possible. Now, scientists at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) have gained new insight into a common type of hiccup known as the sawtooth instability that cools the hot plasma in the center and interferes with the fusion reactions. These findings could help bring fusion energy closer to reality.

"Conventional models explain most instances of the sawtooth crashes, but there is a tenacious subset of observations that we have never been able to explain," said PPPL physicist Christopher Smiet, lead author of a paper reporting the results in Nuclear Fusion. "Explaining those unusual occurrences would fill a gap in understanding the sawtooth phenomenon that has existed for almost 40 years."

Fusion combines light elements in the form of plasma -- the hot, charged state of matter composed of free electrons and atomic nuclei -- and in the process generates massive amounts of energy in the sun and stars. Scientists are seeking to replicate fusion in devices on Earth for a virtually inexhaustible supply of safe and clean power to generate electricity.

Researchers have known for decades that the temperature at the core of fusion plasma often rises slowly and can then suddenly drop -- an unwanted occurrence since the cooler temperature reduces efficiency. The prevailing theory is that the crash occurs when a quantity called the safety factor, which measures the stability of the plasma, drops to a measurement of close to 1. The safety factor relates to how much twist is in the magnetic field in the doughnut-shaped tokamak fusion facilities.

However, some observations suggest that the temperature crash occurs when the safety factor drops to around 0.7. This is quite surprising and cannot be explained by the most widely accepted theories.

The new insight, coming not from plasma physics but from abstract mathematics, shows that when the safety factor takes specific values, one of which is close to 0.7, the magnetic field in the plasma core can change into a different configuration called alternating-hyperbolic. "In this topology, the plasma is lost in the core," Smiet says. "The plasma is expelled from the center in opposite directions. This leads to a new way for the magnetic cage to partially crack, for the temperature in the core to suddenly fall, and for the process to repeat as the magnetic field and temperature slowly recover."

The new insights suggest an exciting new research direction toward keeping more heat within the plasma and producing fusion reactions more efficiently. "If we can't explain these outlier observations, then we don't fully understand what's going on in these machines," Smiet said. "Countering the sawtooth instability can lead to producing hotter, more twisty plasmas and bring us closer to fusion."

This model arose from purely abstract mathematical research. Smiet found a mathematical way to describe the magnetic field in the center of a tokamak. All possible configurations can then be associated with an algebraic structure called a Lie group. "The mathematics is really quite beautiful," Smiet says. "This mathematical group gives you a birds-eye view of all possible magnetic configurations and when one configuration can change into another."

The new model shows that one of the times the magnetic configuration in a tokamak can change is when the safety factor falls to precisely two-thirds, or 0.666. "This is eerily close to the value of 0.7 that has been seen in experiments, particularly so when experimental uncertainty is taken into account," Smiet said. "One of the most beautiful parts of these results," he said, "is that they came from just noodling around with pure mathematics."

Smiet hopes to verify the new model by running experiments on a tokamak. "The mathematics has shown us what to look for," he said, "so now we should be able to see it."

University of East Anglia scientists have helped find a way to control different plant processes - such as when they grow - using nothing but coloured light.

The development, published today in the journal Nature Methods, reveals how coloured light can be used to control biological processes in plants by switching different genes on and off.

The researchers hope that their findings could lead to advances in how plants grow, flower, and adapt to their environment, ultimately allowing increases in crop yields.

The research was led by Heinrich Heine University and the Cluster of Excellence on Plant Sciences (CEPLAS) in Düsseldorf, in collaboration with colleagues at the University of Freiburg and UEA.

Dr Ben Miller, from UEA's School of Biological Sciences, said: "Our team have been working on optogenetics - using light to precisely control biological processes - in plants.

"Using optogenetics in plants hadn't been possible before because plants naturally respond to light as they grow. Any genetic switches controlled by light would therefore be constantly active.

"But we have developed a special system which overcomes this problem and allows us to control different cellular processes in plants using light.

"We can now use a red light to cause gene expression at a precise moment, while an ambient white light can be used as an 'off switch' to reverse the process. This can be repeated any number of times.

"We can use this system to manipulate physiological responses in plants, for example their immune response, and perhaps their development, growth, hormone signalling and stress responses."

The project bridges two hot topics in biology - optogenetics and synthetic biology.

The new tool called PULSE (Plant Usable Light-Switch Elements) is suitable for plants growing under normal day and night cycles.

Dr Miller said: "In the future, this research might mean that we can modulate how plants grow, and respond and adapt to their environment, with light cues.

"For example, we have shown that plant immune responses can be switched on and off using our light-controlled system. If this system was used in crops, we could potentially improve plant defences to pathogens and have an impact by improving yields.

"Using light to control biological processes is far less invasive and more reversible than using chemicals or drugs, so this new system in plants is a really exciting new tool for us to answer fundamental questions in plant biology."