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Bethesda, Maryland (April 10, 2020) -- Today, the American Gastroenterological Association (AGA) published new COVID-19 guidance for gastroenterologists treating patients with inflammatory bowel disease (IBD): AGA Clinical Practice Update on Management of Inflammatory Bowel Disease During the COVID-19 Pandemic: Expert Commentary.

While the COVID-19 pandemic is a global health emergency, patients with IBD have particular concerns for their risk for infection and management of their medical therapies. This clinical practice update incorporates the emerging understanding of COVID-19 and summarizes available guidance for patients with IBD and the providers who take care of them.

Recommendations for gastroenterologists & their patients who have IBD:

1. During this pandemic, patients with IBD should continue IBD therapies including scheduled infusions.

2. Having IBD does not appear to increase the risk of SARS-CoV-2 infection or the development of COVID-19.

3. Instructions for patients with IBD who develop COVID-19 (fever, respiratory symptoms, digestive symptoms, etc.):

a. Stop thiopurines, methotrexate, tofacitinib.

b. Stop biological therapies (including anti-TNF, ustekinumab, vedolizumab).

c. Can restart therapies after complete resolution of COVID-19 symptoms. Patients should

always speak with their health care team before stopping any medication.

4. Doctors should submit cases of IBD and confirmed COVID-19 to the SECURE-IBD registry at
COVIDIBD.org.

A new X-ray detector prototype is on the brink of revolutionizing medical imaging, with dramatic reduction in radiation exposure and the associated health risks, while also boosting resolution in security scanners and research applications, thanks to a collaboration between Los Alamos National Laboratory and Argonne National Laboratory researchers.

"The perovskite material at the heart of our detector prototype can be produced with low-cost fabrication techniques," said Hsinhan (Dave) Tsai, an Oppenheimer Postdoctoral fellow at Los Alamos National Laboratory. "The result is a cost-effective, highly sensitive, and self-powered detector that could radically improve existing X-ray detectors, and potentially lead to a host of unforeseen applications."

The detector replaces silicon-based technology with a structure built around a thin film of the mineral perovskite, resulting in a hundred times more sensitivity than conventional silicon-based detectors. In addition, the new perovskite detector does not require an outside power source to produce electrical signals in response to X-rays.

High sensitivity perovskite detectors could enable dental and medical images that require a tiny fraction of the exposure that accompanies conventional X-ray imaging. Reduced exposure decreases risks for patients and medical staff alike. The fact that perovskite detectors can be made very thin allows them to offer increased resolution for highly detailed images, which will lead to improved medical evaluations and diagnoses. Lower-energy and increased-resolution detectors could also revolutionize security scanners and imaging in X-ray research applications.

Because perovskite is rich in heavy elements, such as lead and iodine, X-rays that easily pass through silicon undetected are more readily absorbed, and detected, in perovskite. As a result, perovskite significantly outperforms silicon, particularly at detecting high-energy X-rays. This is a crucial advantage when it comes to monitoring X-rays at high-energy research facilities, such as synchrotron light sources.

Perovskite films can be deposited on surfaces by spraying solutions that cure and leave thin layers of the material behind As a result, the thin-layer detectors will be much easier and cheaper to produce than silicon-based detectors, which require high-temperature metal deposition under vacuum conditions.

"Potentially, we could use ink-jet types of systems to print large scale detectors," said Tsai. "This would allow us to replace half-million-dollar silicon detector arrays with inexpensive, higher-resolution perovskite alternatives."

In addition to the promise of thin-layer perovskites in X-ray detectors, thicker layers work well provided they include a small voltage source. This suggests that their useful energy range could be extended beyond X-rays to low-energy gamma-rays.

Researchers are interested in genetically modifying trees for a variety of applications, from biofuels to paper production. They also want to steer clear of modifications with unintended consequences. These consequences can arise when intended modifications to one gene results in unexpected changes to other genes. A new model aims to predict these changes, helping to avoid unintended consequences, and hopefully paving the way for more efficient research in the fields of genetic modification and forestry.

The research at issue focuses on lignin, a complex material found in trees that helps to give trees their structure. It is, in effect, what makes wood feel like wood.

"Whether you want to use wood as a biofuel source or to create pulp and paper products, there is a desire to modify the chemical structure of lignin by manipulating lignin-specific genes, resulting in lignin that is easier to break down," says Cranos Williams, corresponding author of a paper on the work and an associate professor of electrical and computer engineering at NC State. "However, you don't want to make changes to a tree's genome that compromise its ability to grow or thrive."

The researchers focused on a tree called Populus trichocarpa, which is a widely used model organism - meaning that scientists who study genetics and tree biology spend a lot of time studying P. trichocarpa.

"Previous research generated models that predict how independent changes to the expression of lignin genes impacted lignin characteristics," says Megan Matthews, first author of the paper, a former Ph.D. student at NC State and a current postdoc at the University of Illinois. "These models, however, do not account for cross-regulatory influences between the genes. So, when we modify a targeted gene, the existing models do not accurately predict the changes we see in how non-targeted genes are being expressed. Not capturing these changes in expression of non-targeted genes hinders our ability to develop accurate gene-modification strategies, increasing the possibility of unintended outcomes in lignin and wood traits.

"To address this challenge, we developed a model that was able to predict the direct and indirect changes across all of the lignin genes, capturing the effects of multiple types of regulation. This allows us to predict how the expression of the non-targeted genes is impacted, as well as the expression of the targeted genes," Matthews says.

"Another of the key merits of this work, versus other models of gene regulation, is that previous models only looked at how the RNA is impacted when genes are modified," Matthews says. "Those models assume the proteins will be impacted in the same way, but that's not always the case. Our model is able to capture some of the changes to proteins that aren't seen in the RNA, or vice versa.

"This model could be incorporated into larger, multi-scale models, providing a computational tool for exploring new approaches to genetically modifying tree species to improve lignin traits for use in a variety of industry sectors."

In other words, by changing one gene, researchers can accidentally mess things up with other genes, creating trees that aren't what they want. The new model can help researchers figure out how to avoid that.

VRAC/LRRC8 chloride channels do not only play a decisive role in the transport of cytostatics, amino acids and neurotransmitters. They can also transport the important messenger substance cGAMP from cell to cell and thus strengthen the immune response to infections with DNA viruses. This has now been demonstrated by Prof. Thomas Jentsch, who originally discovered LRRC8/VRAC channels and works at the Leibniz Research Institute for Molecular Pharmacology (FMP) and the Max Delbrück Center for Molecular Medicine (MDC) in Berlin, together with colleagues from Shanghai led by Prof. Hui Xiao. Since cGAMP is always formed when cells detect DNA outside their nucleus, the discovery is potentially of great importance also for other pathologies such as cancer. The work has now been published in the scientific journal "Immunity".

If DNA viruses such as herpes simplex - the coronavirus, being an RNA virus, does not belong to this group! - infect human cells; this does not go unnoticed. In the cell interior, the so-called cytoplasm, DNA has no place. Thus, if DNA is detected there messenger substances are formed and begin to sound the alarm. The foreign DNA binds to the enzyme cGAS, which synthesizes the 'second messenger' cGAMP. By binding to a receptor called STING, cGAMP activates a cellular signaling cascade that triggers the production of interferons and other factors of the innate immune system. This mechanism has also been observed in tumor cells, in which DNA fragments are released from the nucleus into the cytoplasm, as well as in some bacterial infections.

cGAMP is a highly topical messenger substance

Research on cGAMP has exploded in recent years, partly because it not only acts in the cell where it is produced, but also passes on to other cells. However, it remains unclear how this may happen. In cells that directly contact each other, cGAMP can pass through cell-connecting channels known as "gap junctions". But what about cells that are not in the immediate vicinity?

Researchers led by Prof. Hui Xiao from the Institut Pasteur Shanghai had suspected that further transport pathways must play a role and came across the volume-regulated anion channel VRAC - the ion channel discovered in 2014 by Prof. Thomas Jentsch and his team, and in parallel by Prof. Zhaozhu Qiu (now Johns Hopkins University), who also contributed to the publication in "Immunity". Together, the German-Chinese research team was able to demonstrate with a whole variety of methods that VRAC transports cGAMP both out of the producing cell and into the recipient cell. This leads to the production of interferons in cells that are not infected, thereby strengthening the immune response.

"We now know that VRAC definitely transports cGAMP" says Thomas Jentsch about this significant discovery. "We didn't know this function yet, but it fits well with our previous findings on VRAC, namely that it not only transports chloride, but also other small organic molecules, for instance neurotransmitters, amino acids and cytostatics. The dependence of the cGAMP transport on the subunit LRRC8E - VRAC is always composed of several subunits - which we have now observed, agrees well with our earlier findings, which showed that this subunit supports the transport of glutamate, which is also negatively charged."

The uptake of the messenger substance by VRAC was verified by various cell culture experiments and by electrophysiological approaches. In one experiment, for example, cells were infected with a DNA virus and separated from healthy cells using a filter. The virus infection could not be transmitted - but an interferon response was also observed in the non-infected cells.

Finally, experiments with knock-out mice generated in Berlin which lacked the VRAC subunit LRRC8E provided compelling evidence: if the rodents were infected with herpes viruses, a much higher viral load and lower interferon release were observed than in unmodified control animals. "This was exactly what we expected, because the messenger substance could no longer be transferred from infected cells to neighboring cells due to the absence of the channel. Since this transfer normally strengthens the immune response." explains Professor Jentsch. " the lack of cGAMP-transporting VRAC greatly reduces the defense mechanisms against such viruses."

New strategies against DNA viruses and cancer

The discovery of this new role of VRAC in the body's defense system against DNA viruses, a new addition to the many important functions of VRAC, will attract even more attention to this ion channel. The researchers assume that VRAC might play a similar role in cancer. Indeed, others have recently shown in animal experiments that cGAMP transport from cancer cells to neighboring host cells enhanced the immune response against tumors - but how cGAMP is transported had remained unclear.

Besides VRAC and gap junctions, a folate transporter also transports cGAMP across the membrane, as was shown last year. However, VRAC is found in more cell types and therefore probably plays a greater role. In the future, it might be a viable approach to activate VRAC to enhance the immune response. Possible ways to do this have already been described in the new work.

"The field is incredibly hot," says Thomas Jentsch, "and our discovery offers completely new perspectives for both, infection research and cancer research."

Harvesting sunlight to make energy is a complex reaction that plants do naturally, but isn't well understood.

A research team led by a Washington State University professor has developed a new tool to study how lipids interact with proteins in plants to help understand how photosynthesis happens.

In the paper, published in the Journal of Biological Chemistry earlier this year, the scientists used this new tool to find the lipid that controls when a photosynthetic protein switches from a light harvester to an energy dissipater in plants.

"There's a lot of potential danger with photosynthesis," said Helmut Kirchhoff, professor in WSU's Institute of Biological Chemistry. "If plants take in light energy that isn't used properly for their metabolism, it can poison the plant and kill cells. The switch of light-harvesting proteins is essential to protect the system when there's too much light available."

Until now, nobody knew for sure how plants avoided that toxicity on sunny days. It's an important scientific breakthrough.

High impact paper

The paper's impact was recently chosen by Science magazine as an editor's choice paper for March 2020.

"I was really surprised to be chosen," Kirchhoff said. "We were really excited and honored to be picked in such a top tier journal."

Kirchhoff wrote the paper with co-authors Stefanie Tietz, Ricarda Höhner, and Alice Olson from WSU and Michelle Leuenberger and Graham R Fleming from the University of California, Berkley.

How it works

In the paper, the researchers developed a method for studying how lipids, which are molecules in cell membranes that perform a variety of functions, interact with proteins in chloroplasts, the part of green plant cells that photosynthesize light.

They found that one specific type of lipid, called a nonbilayer lipid, seems to control the switch that the light harvesting protein makes when the plant has enough light and needs to dissipate some of the energy being received.

"We were suspicious that this nonbilayer lipid had a role in controlling the structure and function of membrane proteins," Kirchhoff said. "We knew it had to have a function to be there because it's the most abundant lipid in photosynthetic membranes. We just didn't know exactly what that role would be."

Future uses of findings

In a changing climate with an increasing human population, growing more food with fewer resources will be essential. This new finding could one day lead to a method for optimizing photosynthesis in crops for specific environments, so excess energy doesn't have to be wasted, Kirchhoff said.

"We're still very early on, but we're excited by what we've found in this paper," he said. "And we'll continue to use our new process to study other lipid-protein interactions to see what else we can learn."

In a recent study published in the Proceedings of the National Academy of Sciences (PNAS), University of California San Diego researchers moved one step closer to the ability to make heparin in cultured cells. Heparin is a potent anti-coagulant and the most prescribed drug in hospitals, yet cell-culture-based production of heparin is currently not possible.

In particular, the researchers found a critical gene in heparin biosynthesis: ZNF263 (zinc-finger protein 263). The researchers believe this gene regulator is a key discovery on the way to industrial heparin production. The idea would be to control this regulator in industrial cell lines using genetic engineering, paving the way for safe industrial production of heparin in well-controlled cell culture.

Heparin is currently produced by extracting the drug from pig intestines, which is a concern for safety, sustainability, and security reasons. Millions of pigs are needed each year to meet our needs, and most manufacturing is done outside the USA. Furthermore, ten years ago, contaminants from the pig preparations led to dozens of deaths. Thus, there is a need to develop sustainable recombinant production. The work in PNAS provides new insights on exactly how cells control synthesis of heparin.

Heparin regulation

Heparin is a special subtype of a more general class of carbohydrates, called heparan sulfates, that are produced by a wide range of cells, both in the human body, as well as in cell culture. Yet, heparin is exclusively produced in a special type of blood cells called mast cells. To this day, heparin cannot be successfully produced in cell culture.

Researchers at UC San Diego reasoned that heparin synthesis must be under the control of certain gene regulators (called transcription factors), whose tissue-specific occurrence might give mast cells the unique ability to produce heparin.

Since regulators for heparin were not known, a research team led by UC San Diego professors Jeffrey Esko and Nathan Lewis used bioinformatic software to scan the genes encoding enzymes involved in heparin production and specifically look for sequence elements that could represent binding sites for transcription factors. The existence of such a binding site could indicate that the respective gene is regulated by a corresponding gene regulator protein, i.e. a transcription factor.

"One DNA sequence that stood out the most is preferred by a transcription factor called ZNF263 (zinc-finger protein 263)," explains UC San Diego professor Nathan E. Lewis, who holds appointments in the UC San Diego School of Medicine's Department of Pediatrics and in the UC San Diego Jacobs School of Engineering's Department of Bioengineering.

"While some research has been done on this gene regulator, this is the first major regulator involved in heparin synthesis," said Lewis. He is also Co-Director of the CHO Systems Biology Center at the UC San Diego Jacobs School of Engineering.

Using the gene-editing technology, CRISPR/Cas9, the UC San Diego researchers mutated ZNF263 in a human cell line that normally does not produce heparin. They found that the heparan sulfate that this cell line would normally produce was now chemically altered and showed a reactivity that was closer to heparin.

Experiments further showed that ZNF263 represses key genes involved in heparin production. Interestingly, analysis of gene expression data from human white blood cells showed suppression of ZNF263 in mast cells (which produce heparin in vivo) and basophils, which are related to mast cells. The researchers report that ZNF263 appears to be an active repressor of heparin biosynthesis throughout most cell types, and mast cells are enabled to produce heparin because ZNF263 is suppressed in these cells.

This finding could have important relevance in biotechnology. Cell lines used in industry (such as CHO cells that normally are unable to produce heparin) could be genetically modified to inactivate ZNF263 which could enable them to produce heparin, like mast cells do.

Philipp Spahn, a project scientist in Nathan Lewis' lab in the Departments of Pediatrics and Bioengineering at UC San Diego, described further directions the team is pursuing: "Our bioinformatic analysis revealed several additional potential gene regulators which can also contribute to heparin production and are now exciting objects of further study."

April 9, 2020 -- The Lancet commentary "Centring sexual and reproductive health and justice in the global COVID-19 response" highlights the detrimental impact of the global COVID-19 pandemic response on sexual and reproductive health and rights (SRHR). The piece emphasizes the threat to SRH services, caused by policies designating these services as non-essential and diverting resources, and calls for vigilance from the SRH community to prevent access to these services from being lost. "Global responses to the coronavirus disease 2019 (COVID-19) pandemic are converging with pervasive, existing sexual and reproductive health and justice inequities to disproportionately impact the health, wellbeing, and economic stability of women, girls, and vulnerable populations," writes Terry McGovern, Chair of the Heilbrunn Department of Population and Family Health, and co-authors.

Highlighting the disproportionate social and economic burden on women, girls, and vulnerable populations exacerbated by the pandemic, the authors argue that "a sexual and reproductive health and justice framework--one that centers human rights, acknowledges intersecting injustices, recognizes power structures, and unites across identities--is essential for monitoring and addressing the inequitable gender, health, and social effects of COVID-19.

A multi-disciplinary group of academics and practitioners, including epidemiologists, health care workers, lawyers, and community-based organizers, the authors have expertise in sexual and reproductive health service provision and access, gender-based violence, global humanitarian response, human rights, disease surveillance, stigma, and the specific needs of women, girls, and vulnerable populations.

"Advocates must continue to fight the exploitation of the COVID-19 crisis to further an agenda that restricts access to essential sexual and reproductive health services, particularly abortion, and targets immigrants and adolescents," noted McGovern, who is also director of the Program on Global Health Justice and Governance at Columbia Mailman School.

Nano-catalysts usually have higher catalytic activity than traditional bulk catalysts. And it is widely acknowledged that the smaller the particle size of the active component is, the higher the activity would be. However, the active component with small size tends to agglomerate or further grow into large particles. Many reaction processes, such as hydrocarbon cracking and combustion, methane dry/wet reforming and automobile exhaust gas purification, have to be operated at very high temperatures, it will lead to the decreasing of activity and product selectivity due to sintering at high temperatures, ultimately limits the practical application of nano-catalysts. Many researchers believe that the sintering of nanoparticles involves two processes: one is the ripening process, single atom or molecular species move from one particle to another; the other is the migration process, whole particles grow into large particles after migration and aggregation. Because the ripening process can hardly be avoided at high temperature, the current strategy to improve the stability of nano-catalysts is to inhibit the migration of nanoparticles on the basis of "confinement effect" or to construct a "migration barrier".

Recently, Pt/CeO2/NiAl2O4/Al2O3@SiO2 model catalyst, based on the "composite energy trap" model, was developed by the State Key Laboratory of Rare Earth Resource Utilization of Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, which can effectively inhibit the migration and agglomeration of loaded nanoparticles. The model catalyst still remains high activity after aging at 1000 ?. The results of DFT indicate that the higher stability of the model catalyst should be attributed to the existence of two kinds of "confinement effect" in its structure, the "composite energy well" model is also suitable for the research and development of other supported catalysts. The first authors of this paper are Jingwei Li and Kai Li, and the correspondent authors are associate professor Yibo Zhang and professor Xiangguang Yang.

Imagine the advances to predictive modeling if you could infer something about how light amplifies colors in a bird's plumage from the way seismic waves propagate through mountain systems.

That's a bit of hyperbole that nevertheless suggests the "beautiful" utility of new mathematical formulas devised by Princeton Professor of Chemistry Salvatore Torquato and sixth-year graduate student Jaeuk Kim of the Department of Physics as they advance our understanding of how different types of waves behave inside materials.

Torquato, the Lewis Bernard Professor of Natural Sciences and director of the Complex Materials Theory Group, published research this week in the Proceedings of the National Academy of Sciences (PNAS) linking wave phenomena that has never previously been linked. For the first time, the research employs a unified approach that melds the behavior of elastodynamic (sound) waves with that of electromagnetic (light) waves as they propagate through heterogeneous, or composite, materials.

Torquato and Kim also demonstrate that the way these waves move through a heterogeneous material in turn elucidates characteristics of the material microstructure itself. The microstructure - the spatial arrangement of the different materials that comprise the heterogeneous material - impacts the way waves propagate.

This is the basic idea behind ultrasound scans, or sonography, that create images of structures within your body.

A homogeneous system consists of a single material. A heterogeneous, or composite, system is a mixture. But the mixture of these individual materials - called phases - do not combine evenly; they inhabit distinct domains within that system. Light and sound waves move through a given composite and, as they encounter different phases with different physical properties, they behave differently, scatter, and interfere. Due to the resulting interference, the wave speeds change and the waves can attenuate, or lose energy.

The formulas developed under this research will allow scientists to predict how waves act in these complex systems without having to solve for two sets of differential equations that govern light and sound waves, respectively. They can estimate the effective wave speeds and degree of attenuation, or the rate at which waves degrade within a material, for a wider range of wavelengths than that on which previous theories operate.

"What we're predicting is the effective behavior of this wave through a complicated system," said Torquato, a theoretical chemist. "And it turns out that the effective properties of both electromagnetic and elastodynamic waves will depend upon the wavelengths associated with those particular waves.

"Light waves, for instance, are governed by Maxwell's differential equations for electromagnetic waves. Sound waves are governed by another set of differential equations. So normally, when you're working on wave phenomena, you have these two communities that typically don't talk to each other," added Torquato. "What we have done, which is way out of the box, is to create a formulation that allows us to attack each problem in a unified manner.

"Then, we melded the formulas together to show that if you can tell me the response of a material to an electromagnetic wave, I can tell you something about the response of that same material to sound waves. So now, you have these predictive formulas that can be applied so that you don't have to constantly validate the theory via full-blown computer simulations every time you change the parameters. You're able to access and predict phenomena that people could not even contemplate before."

The research centers on heterogeneous systems because these systems are ideal to achieve multiple types of desired properties, called multifunctionality, which means that the best properties of composites can be combined to exhibit specific responses to the different types of waves. Materials can then be designed, for example, to absorb waves or allow them to be transmitted without attenuation.

"Previous multifunctional designs mainly have focused on static transport and elastic properties because conventional theories were not accurate in predicting wave phenomena," said Kim. "Thus, our theory will aid the rational design of multifunctional composites with desired wave characteristics."

Driving towards a future application, these formulas could allow for the design of new, multifunctional materials that exhibit specific responses to waves, paving the way to engineered hyperuniform materials with exotic effective properties. They could one day enable the design of multifunctional composites that might include structural components for spacecraft, which require high stiffness and electromagnetic absorption, or heat sinks for central processing units (CPUs) and other electrical devices that can simultaneously suppress mechanical vibrations.

"This work was successful thanks to Professor Torquato's insights in working across disciplines. It was exciting to bridge the knowledge of two different communities - optics and acoustics - to achieve this research," said Kim.

CHICAGO (April 9, 2020): Within a month of the University of California San Francisco (UCSF) Health treating its first patient with coronavirus disease 2019 (COVID-19) on Feb. 3, UCSF surgeons began formulating a plan to respond to the pandemic and help manage the health care system's available resources. The comprehensive rapid response plan--one of the earliest surgical strategies for handling the outbreak reported in the nation--appears online as an "article in press" on the Journal of the American College of Surgeons website in advance of print.

The multitier plan was a collaboration between the UCSF department of surgery and the hospital's other departments, according to the article's authors. Their actions included reducing operating room volume by 80 percent to ensure adequate capacity to care for an anticipated influx of COVID-19 patients, safeguarding personal protective equipment (PPE), preparing for a dwindling workforce due to illness and other reasons, and providing regular communication to departmental staff about the pandemic.

"In two weeks, we have dramatically changed the way we approach surgical care and come together as a community for the greater good of our city and patients. The speed with which this has occurred is unprecedented," the authors write. "Our response efforts were early and aggressive, and we made tough decisions," said study coauthor Elizabeth Wick, MD, FACS, professor of surgery at UCSF. "We canceled elective surgical cases before any other facility in the country that we know of. By starting early, we figured out a way to focus on urgent operations before the situation became worse."

Prioritizing operations

On March 13, the American College of Surgeons (ACS)1 recommended that hospitals consider postponing elective, nonurgent surgical procedures, thus freeing hospital beds and other resources for COVID-19 patients. This recommendation left it to individual institutions to determine how to triage, or assign degrees of urgency to, scheduled operations, and was followed with another guidance document on March 17 to aid in surgical decision making to triage operations.2 Even before then, in early March, the UCSF department of surgery had already developed triage guidelines for operations, according to Dr. Wick.

Initially the multidisciplinary team of surgeons defined essential surgical cases as those that would result in an adverse outcome (such as disease progression) if the patient did not undergo the procedure within seven days. The surgeons flagged the priority level in each patient's electronic health record, which Dr. Wick said is helping with organizing the case backlog.

As virus-related health care shortages in other countries became news, the surgical team quickly responded with changes. They reportedly began to prioritize cases based on not only the expected results of delaying the procedure but also the extent that the procedure would use hospital resources, such as ventilators and blood. Additionally, they considered whether nonsurgical treatment was an option.

From an initial 25 percent reduction in operating room volume starting on March 2, the surgeons succeeded in lowering the surgical volume by 80 percent in mid-March, Dr. Wick reported.

Because adjusting surgical care was a crucial step in managing available health care resources, she said surgeons had representation on all UCSF COVID-19 work committees.

Reassigning surgeons to optimize workforce

The department of surgery also developed a plan to optimize the workforce during the pandemic. For instance, the department reassigned some surgeons, based on their competencies, to work in inpatient units, the emergency department, or the system's Level I trauma center.

To minimize workers' exposure to the coronavirus, the department limited surgeons to work at a single hospital site in the health care system and reduced the number of surgeons on each surgical service daily. The same surgical team worked for several days straight so others would be available to work if a viral exposure occurred on that service, Dr. Wick said.

Anticipating shortages of masks, the surgical department created guidelines for which types of PPE to wear in the operating room and when to wear single-use masks versus reusing them.

Putting patients first

It is too soon, Dr. Wick noted, to know whether their rapid response improved outcomes for patients and staff. She said, "We hope we took the necessary measures that will allow UCSF Health to continue to safely and effectively care for surgical patients requiring urgent operations as well as for COVID-19 patients."

She credits their ability to implement a rapid COVID-19 response to San Francisco's early city ordinances requiring residents to stay home and mandating hospitals to restrict visitors. These directives helped patients understand the need to have their nonurgent operations postponed, Dr. Wick said. She also commended strong departmental leadership that emphasized that everyone should prioritize "what was right for the patients."

Dr. Wick said her team members decided to quickly publicize their response plan hoping their experience would help other surgical facilities navigate "this uncharted territory." She said their plan is scaleable to other health care systems and smaller hospitals that have strong leadership and good communication about the purpose of the changes.

Analyses of four fossilized molars newly excavated along the left bank of the Yuruá River in the Peruvian Amazon suggest another primate lineage distinct from the Platyrrhini - until now considered to be the only primate group ever to inhabit the New World - also occupied the New World for a brief period of time. The teeth strongly resemble those of Parapithecidae, a now-extinct family of higher-order primates that resided in Northern Africa around the Eocene (56 to 33.9 million years ago) and Oligocene period (33.9 million to 23 million years ago). Like ancestors of platyrrhine primates, these African-originated parapithecids potentially rafted across the Atlantic - a narrower, yet turbulent ocean at the time - around 35 to 32 million years ago, the researchers postulate. Their results offer another intriguing detail about the origins of New World mammals and may help inform how the ancestors shaped one of the most biodiverse regions on Earth. Erik Seiffert and colleagues analyzed primate teeth discovered at a 100-meter-long sedimentary deposit along Yuruá River and found these teeth were radically different - lumpier and more bulbous, among other features - than those of platyrrhines. Statistical probability analysis placed the species, which the authors named Ucayalipithecus perdita, deep within African primate groups Parapithecoidea and Parapithecidae. Ucayalipithecus' ancestors possibly rafted to the New World across the Atlantic Ocean around the time when sea levels had dropped, in an independent rafting event from the African platyrrhines, the analyses showed. Both parapithecids and Platyrrhini must have been remarkably adaptable to harsh conditions to have survived the crossing, the authors note. Upon arrival, the primates must also have had to immediately adjust their foraging behavior to the unfamiliar land and compete for food and territory, as they both appeared to have persisted around the same time - for at least 11.5 million years. Thus, these early primates were likely highly resilient and behaviorally versatile, the authors say. In a related Perspective, Marc Godinot further explores this concept and poses questions for future exploration.

Strong winds blow high in the atmosphere of the brown dwarf 2MASS J1047+21, according to a new study, which presents a simple method to deduce the windspeed in other brown dwarf atmospheres, too. By monitoring the brown dwarf's infrared and radio emissions, the researchers were able to derive the distant world's powerful winds - which whip eastward at an average of 660 meters per second, or roughly 2,400 kilometers per hour. The results demonstrate a technique that could be used to characterize atmospheres of exoplanets. Brown dwarfs - bodies with masses between large planets and small stars - share many of the same rotational and atmospheric characteristics as gas giant planets. For gas giants within the Solar System like Jupiter, it's easy to observe the latitudinal wind patterns that dominate their atmospheres. The speed of those winds can be derived by comparing the movement of clouds in Jupiter's atmosphere to the radio emissions caused by the rotation of the planet's interior. Now, Katelyn Allers and colleagues show how this approach can be adapted to measure the winds on gas giants and brown dwarfs far outside our Solar System. Allers et al. observed 2MASS J1047+21, a nearby brown dwarf, and determined its rotational periods at infrared (rotation of the atmosphere) and radio (rotation of the interior) wavelengths. The difference between these measurements allowed the authors to derive the brown dwarf's average wind speed and direction - about 660 meters per second in an west-east direction. "Our method for determining the wind speed can in principle also be applied to exoplanets," say the authors, "which have similar rotation rates and periodic variability to brown dwarfs."

Astronomers have used the National Science Foundation's Karl G. Jansky Very Large Array (VLA) and NASA's Spitzer Space Telescope to make the first measurement of wind speed on a brown dwarf -- an object intermediate in mass between a planet and a star.

Based on facts known about the giant planets Jupiter and Saturn in our own Solar System, a team of scientists led by Katelyn Allers of Bucknell University realized that they possibly could measure a brown dwarf's wind speed by combining radio observations from the VLA and infrared observations from Spitzer.

"When we realized this, we were surprised that no one else had already done it," Allers said.

The astronomers studied a brown dwarf called 2MASS J10475385+2124234, an object roughly the same size as Jupiter, but roughly 40 times more massive, about 34 light-years from Earth. Brown dwarfs, sometimes called "failed stars," are more massive than planets, but not massive enough to cause the thermonuclear reactions at their cores that power stars.

"We noted that the rotation period of Jupiter as determined by radio observations is different from the rotation period determined by observations at visible and infrared wavelengths," Allers said.

That difference, she explained, is because the radio emission is caused by electrons interacting with the planet's magnetic field, which is rooted deep in the planet's interior, while the infrared emission comes from the top of the atmosphere. The atmosphere is rotating more quickly than the interior of the planet, and the corresponding difference in velocities is due to atmospheric winds.

"Because we expect the same mechanisms to be at work in the brown dwarf, we decided to measure its rotation speeds with both radio and infrared telescopes," said Johanna Vos, of the American Museum of Natural History.

They observed 2MASS J10475385+2124234 with Spitzer in 2017 and 2018, and found that its infrared brightness varied regularly, likely because of the rotation of some long-lived feature in its upper atmosphere. The team did VLA observations in 2018 to measure the rotation period of the object's interior.

Just as with Jupiter, they found that the brown dwarf's atmosphere is rotating faster than its interior, with a calculated wind speed of about 1425 miles per hour. This is significantly faster than Jupiter's wind speed, about 230 mph.

"This agrees with theory and simulations that predict higher wind speeds in brown dwarfs," Allers said.

The astronomers said their technique can be used to measure winds not only on other brown dwarfs, but also on extrasolar planets.

"Because the magnetic fields of giant exoplanets are weaker than those of brown dwarfs, the radio measurements will need to be done at lower frequencies than those used for 2MASS J10475385+2124234, said Peter Williams of the Center for Astrophysics, Harvard & Smithsonian, and the American Astronomical Society.

"We're excited that our method can now be used to help us better understand the atmospheric dynamics of brown dwarfs and extrasolar planets," Allers said.

Four fossilized monkey teeth discovered deep in the Peruvian Amazon provide new evidence that more than one group of ancient primates journeyed across the Atlantic Ocean from Africa, according to new USC research just published in the journal Science.

The teeth are from a newly discovered species belonging to an extinct family of African primates known as parapithecids. Fossils discovered at the same site in Peru had earlier offered the first proof that South American monkeys evolved from African primates.

The monkeys are believed to have made the more than 900-mile trip on floating rafts of vegetation that broke off from coastlines, possibly during a storm.

"This is a completely unique discovery," said Erik Seiffert, the study's lead author and Professor of Clinical Integrative Anatomical Sciences at Keck School of Medicine of USC. "It shows that in addition to the New World monkeys and a group of rodents known as caviomorphs - there is this third lineage of mammals that somehow made this very improbable transatlantic journey to get from Africa to South America."

Researchers have named the extinct monkey Ucayalipithecus perdita. The name comes from Ucayali, the area of the Peruvian Amazon where the teeth were found, pithikos, the Greek word for monkey and perdita, the Latin word for lost.

Ucayalipithecus perdita would have been very small, similar in size to a modern-day marmoset.

Dating the migration

Researchers believe the site in Ucayali where the teeth were found is from a geological epoch known as the Oligocene, which extended from about 34 million to 23 million years ago.

Based on the age of the site and the closeness of Ucayalipithecus to its fossil relatives from Egypt, researchers estimate the migration might have occurred around 34 million years ago.

"We're suggesting that this group might have made it over to South America right around what we call the Eocene-Oligocene Boundary, a time period between two geological epochs, when the Antarctic ice sheet started to build up and the sea level fell," said Seiffert. "That might have played a role in making it a bit easier for these primates to actually get across the Atlantic Ocean."

An improbable discovery

Two of the Ucayalipithecus perdita teeth were identified by Argentinean co-authors of the study in 2015 showing that New World monkeys had African forebears. When Seiffert was asked to help describe these specimens in 2016, he noticed the similarity of the two broken upper molars to an extinct 32 million-year-old parapithecid monkey species from Egypt he had studied previously.

An expedition to the Peruvian fossil site in 2016 led to the discovery of two more teeth belonging to this new species. The resemblance of these additional lower teeth to those of the Egyptian monkey teeth confirmed to Seiffert that Ucayalipithecus was descended from African ancestors.

"The thing that strikes me about this study more than any other I've been involved in is just how improbable all of it is," said Seiffert. "The fact that it's this remote site in the middle of nowhere, that the chances of finding these pieces is extremely small, to the fact that we're revealing this very improbable journey that was made by these early monkeys, it's all quite remarkable."