Earth

NASA-NOAA's Suomi NPP satellite provided an infrared look at Tropical Storm Karina in the Eastern Pacific Ocean that gave forecasters a nighttime view of the storm. It revealed a slightly more organized tropical storm.

NASA's Night-Time View  

On Sept. 15 at 6:50 a.m. EDT (3:50 a.m. PDT/1050 UTC), the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP passed over the Eastern Pacific Ocean and captured an early morning image of Tropical Storm Karina. The image showed that Karina continued to become a little better organized with a concentrated area of deep convection near and over the estimated low-level center. The image was created using the NASA Worldview application at NASA's Goddard Space Flight Center in Greenbelt, Md.

By 11 a.m. EDT (8 a.m. PDT) on Sept. 15, Andrew Latto, Hurricane Specialist at NOAA's National Hurricane Center in Miami, Fla. noted in the storm's Discussion, "Karina has changed little in organization over the past several hours. [It has] a concentrated area of deep convection mostly over the southwestern portion of the circulation and over the estimated position of the low-level center."

Karina's Status on Sept. 15

At 11 a.m. EDT (1500 UTC), the center of Tropical Storm Karina was located near latitude 20.4 degrees north and longitude 121.1 degrees west. That is about 740 miles (1,190 km) west of the southern tip of Baja California, Mexico.

Karina was moving toward the northwest near 10 mph (17 kph), and this motion is expected to continue for the next couple of days. A turn to the west and then toward the west-southwest is expected late this week. Maximum sustained winds were near 60 mph (95 kph) with higher gusts. Some weakening is forecast during the next 48 hours. The estimated minimum central pressure was 996 millibars.

Karina's Forecast

"The cyclone is forecast to move over progressively cooler waters and into a drier, more stable atmosphere over the next couple of days. These conditions should induce a weakening trend soon, and the deep convection is expected to gradually wane during that time," Latto said in the Discussion.

Gradual weakening should begin by tonight, and Karina is forecast to become a remnant low in two or three days.

As anxiety and depression rise in the country, primary care clinics, especially in rural areas, are facing increased patient needs. One way to address this is to bolster healthcare providers' ability to diagnose and treat patients with common mental health disorders.

Researchers at UW Medicine found that primary-care physicians and rural clinic staff felt more skilled in delivering mental health care if they used a model known as collaborative care.

The results were published Sept. 14 in the Annals of Family Medicine, and add to the evidence supporting collaborative care's effectiveness.

In the model, primary-care physicians retain primary responsibility to treat behavioral health disorders with the support of two team members: a care manager (e.g., social workers, therapists, nurses) and a consulting psychiatrist. Consulting psychiatrists provide recommendations on patient care through weekly caseload reviews conducted online.

"We found that primary-care doctors involved in this collaboration got better at diagnosing, prescribing, and working as a team," said lead author Dr. Morhaf Al Achkar, associate professor of family medicine at the University of Washington School of Medicine.

In the qualitative study, researchers interviewed 17 clinical, support, and administrative staff at three rural clinics in Washington state. All interviewees said the consultations improved their competence to identify and treat psychiatric disorders.

Researchers concluded that weekly systematic case reviews using telepsychiatry consultation functioned both as a model for patient care and as a workforce training and development strategy.

The study was conducted by Rural PREP (Collaborative for Rural Primary care Research, Education, and Practice), a UW School of Medicine-led collaboration funded by the U.S. Health Resources and Services Administration to improve training of rural primary-care professionals.

"The learning was bi-directional," said Al Achkar. Primary-care doctors learned how to better work with patients. Care managers learned to appreciate how medical issues affect mental health and how to diagnose and assess mental health issues. Consulting psychiatrists learned how to coach a primary-care team.

Al Achkar said clinic staff know the community and share that knowledge to help the consulting psychiatrists. And, he said, clinic staff learned to treat mental health as a chronic disease like hypertension and diabetes.

Collaborative care was developed at the UW School of Medicine. It employs principles of effective chronic illness care: Focus on defined patient populations, track these patients in a registry, and measure their progress.

The model was pioneered by the late Dr. Wayne Katon, former vice chair of Psychiatry and Behavioral Sciences, who saw a link between depression and physical health. The model has been widely disseminated throughout the United States by the Advancing Integrated Mental Health Solutions (AIMS) Center at the Department of Psychiatry and Behavioral Sciences.

More than 80 clinical trials support the effectiveness of collaborative care in treating behavioral health disorders in primary care, and Medicare billing codes and policies in many states support its implementation. Based on the findings of the recent study, researchers said the additional benefit of increasing the skills of the primary-care workforce should be considered as healthcare organizations consider costs and benefits of implementing collaborative care.

The devastating effects of human activity on wildlife in the American tropics over the last 500 years are revealed in a new study published today.

More than half of the species in local 'assemblages' - sets of co-existing species - of medium and large mammals living in the Neotropics of Meso and South America have died out since the region was first colonised by Europeans in the 1500s.

Researchers at the University of East Anglia (UEA), in the UK, and University of São Paulo (USP), Brazil, found that human activity such as habitat change and overhunting is largely responsible for the overwhelming loss, or 'defaunation', in mammal diversity across Latin America.

The study, published in the journal Scientific Reports, compared all animal inventories at over 1000 Neotropical study sites published over the past 30 years with baseline data going back to the Colonial era.

The findings draw on a compilation of 1,029 separate mammal assemblages - typically a few kilometres apart from each other - spanning approximately 10,700 km and 85° of latitude across 23 countries, from Mexico to Argentina and Chile.

They reveal that the dominant cause of local species extinction and assemblage downsizing - the reduction in body size within each assemblage - is a direct result of habitat changes such as farming, logging and fires, and aggravated by the chronic process of overhunting.

Dr Juliano André Bogoni, a postdoctoral researcher sponsored by the São Paulo Research Foundation and working at UEA's School of Environmental Sciences, led the study with Prof Carlos Peres, also of UEA, and Prof Katia Ferraz from USP.

Dr Bogoni said: "Our findings can be used to inform international conservation policies to prevent further erosion of, or restore, native biodiversity. Further conservation efforts should be mobilized to prevent the most faunally-intact biomes, such as Amazonia and the Pantanal wetlands, from following in the footsteps of 'empty ecosystems' that are now typical of historically degraded areas such as the Brazilian Atlantic Forest and the Caatinga.

"This includes effective implementation and law enforcement in existing protected areas, and curbing political pressures to either downgrade or downsize these areas. Greater investment should be allocated to more effective control of illegal hunting, particularly commercial hunting, deforestation, and anthropogenic fires, as well as ensure that fully implemented protected areas are working."

Prof Peres said: "Sound resource management should be sensitive to the socioeconomic context, while recruiting rather than antagonizing potential local alliances who can effectively fill the institutional void in low-governance regions.

"Hominins and other mammals have co-existed since the earliest Paleolithic hunters wielding stone tools some three million years ago. Over this long timescale biodiversity losses have only recently accelerated to breakneck speeds since the industrial revolution.

"Let us make sure that this relentless wave of local extinctions is rapidly decelerated, or else the prospects for Neotropical mammals and other vertebrates will look increasingly bleak."

The team looked at 165 species and analysed local losses in more than 1000 sets of medium to large-bodied mammal species that had been surveyed across the Neotropics.

On average more than 56 per cent of the local wildlife within mammal assemblages across the Neotropics were wiped out, with ungulates lowland tapir and white-lipped peccary comprising the most losses. The extent of defaunation was widespread, but increasingly affecting relatively intact major biomes that are rapidly succumbing to encroaching deforestation frontiers.

Over time the assemblage-wide mammal body mass distribution greatly reduced from a historical 95th-percentile of approximately 14 kg to only about 4 kg in modern assemblages.

A research group consisting of Associate Professor FUKAYAMA Hiroshi (Kobe University, Graduate School of Agricultural Science) and Professor MATSUMURA Hiroyoshi (Ritsumeikan University) et al. have succeeded in greatly increasing the catalytic activity of Rubisco (*1), the enzyme which fixes carbon from CO2 in plant photosynthesis. The research team also hypothesized the mechanism which determines the catalytic activity of Rubisco, based on structural analysis of the proteins.

In the future, it is hoped that increasing the photosynthetic ability of agricultural crops will lead to increased yields.

These results were published in the international scientific journal Molecular Plant on August 31.

Main Points

Photosynthesis determines a plant's growth rate. The low activity of the enzyme Rubisco, which is the catalyst for the reaction that turns CO2 into organic carbon, limits the rate of photosynthesis.

Rubisco consists of two types of protein; large subunits (RbcL) and small subunits (RbcS). RbcS is an important factor for determining the speed of the catalyst.

A hybrid Rubisco consisting of rice RbcL and sorghum RbcS demonstrated a catalytic rate that was approximately 2 times higher than that of rice Rubisco. This is believed to be the first time in the world that such a large increase in Rubisco activity has been achieved.

The 102 amino acid found inside RbcS is isoleucine in rice and leucine in sorghum. Analysis of the protein structures indicated the possibility that the difference in amino acid type could affect the catalytic activity.

It is hoped that the method to improve photosynthesis demonstrated in this study could be applied to many other crops which, like rice, have low Rubisco activity such as wheat, soybean and potato.

Research Background

Growth speed in plants is mainly determined by photosynthetic ability. Thus improving photosynthesis in agricultural crops can increase their yield. In photosynthesis, Rubisco is an enzyme that acts as the initial catalyst for the reaction which turns CO2 into organic carbon. However, Rubisco has two major drawbacks which limit photosynthesis: its catalytic activity is very low, and it can be inhibited by O2 (ie. Rubisco can mistakenly fix to O2 molecules instead of CO2 molecules, creating a toxic compound that needs to be recycled by the plant).

Rubisco's catalytic activity varies depending on the type of plant. Most major crops, such as rice, wheat and soybean are C3 plants that use regular photosynthesis. C4 plants, such as corn and sugarcane, on the other hand, have acquired a mechanism to concentrate CO2 (the C4 photosynthetic pathway).

The catalytic rate is low in C3 plants, whereas in C4 plants it tends to be high. Rubisco with high catalytic activity tends to be inhibited easily by oxygen, therefore it cannot function effectively in atmospheric conditions where there is a low concentration of CO2 if the plant doesn't have a CO2-concentrating mechanism. However, as the amount of atmospheric CO2 is continuing to increase, it is believed that if C3 plants had the same highly active type of Rubisco as C4 plants then this could be utilized to improve photosynthetic ability.

Research Findings:

Rubisco is made up of two types of protein- large subunits (RbcL) and small subunits (RbcS) (Figure 1). The sequence of the amino acids in RbcS varies greatly between species. This team has been focusing on conducting research into RbcS. They genetically modified rice (a C3 plant) by transferring RbcS from the C4 plant sorghum, successfully increasing the catalytic rate of rice Rubisco 1.5 times. This rice with sorghum RbcS inserted (SS line), produced a chimera form of Rubisco from both sorghum RbcS and rice RbcS. Next, the rice RbcS gene was knocked out in the sorghum RbcS incorporated rice plants using CRISPR/Cas9 gene editing.

In this CSS line (sorghum RbcS transferred/rice RbcS knocked out), the rice RbcS was completely replaced by sorghum RbcS, producing hybrid Rubisco. This approximately doubled the catalytic rate to that which is equivalent to C4 plants (Figure 2). Although many researchers have been able to improve Rubisco's catalytic characteristics, there have been no examples of such a large increase being achieved. Furthermore, CSS line plants demonstrated a higher photosynthetic rate than unmodified (wild type) rice under high CO2 conditions, even though the amount of Rubisco in their leaves was over 30% less.

Subsequently, the researchers conducted x-ray crystallography (*2) in order to illuminate the mechanism by which sorghum RbcS increases Rubisco's catalytic activity. RbcL is present in Rubisco's catalytic site. Near this catalytic site, there is a structure called RbcS βC (Figure 3). The 102 amino acid found in βC is isoleucine in rice and leucine in sorghum. Leucine has smaller molecules than isoleucine. Therefore, it is thought that in sorghum RbcS the gaps between amino acid molecules become bigger, making the reaction site more pliable and thus increasing catalytic activity. Although further research is necessary to prove this, it is believed to be a previously unproposed ground-breaking theory for Rubisco research.

Conclusion

The CSS line produced in this study demonstrated high photosynthetic ability, however crop yield was not improved. Hopefully, it will be possible to vastly improve plant growth and productivity through appropriate control of Rubisco levels.

The current research used the C3 plant rice, however it is vital to consider the applications of this methodology and investigate whether or not the same strategy can be used to increase Rubisco's catalytic activity in other major crops, such as wheat, soybean and potato.

It is thought that the 102 amino acid is an important determinant of the catalytic activity. Further research is being carried out to investigate this; for example by replacing only the amino acid at the 102 site with another amino acid and producing Rubisco.

Myotonic dystrophy type I is the most common type of adult-onset muscular dystrophy. People with the condition inherit repeated DNA segments that lead to the toxic buildup of repetitive RNA, the messenger that carries a gene's recipe to the cell's protein-making machinery. As a result, people born with myotonic dystrophy experience progressive muscle wasting and weakness and a wide variety of other debilitating symptoms.

CRISPR-Cas9 is a technique increasingly used in efforts to correct the genetic (DNA) defects that cause a variety of diseases. A few years ago, University of California San Diego School of Medicine researchers redirected the technique to instead modify RNA in a method they call RNA-targeting Cas9 (RCas9).

In a new study, publishing September 14, 2020 in Nature Biomedical Engineering, the team demonstrates that one dose of RCas9 gene therapy can chew up toxic RNA and almost completely reverse symptoms in a mouse model of myotonic dystrophy.

"Many other severe neuromuscular diseases, such as Huntington's and ALS, are also caused by similar RNA buildup," said senior author Gene Yeo, PhD, professor of cellular and molecular medicine at UC San Diego School of Medicine. "There are no cures for these diseases." Yeo led the study with collaborators at Locanabio, Inc. and the University of Florida.

Normally, CRISPR-Cas9 works by directing an enzyme called Cas9 to cut a specific target gene (DNA), thereby allowing researchers to inactivate or replace the gene. RCas9 works similarly, but Cas9 is guided to an RNA molecule instead of DNA.

In a 2016 study, Yeo's team demonstrated that RCas9 worked by using it to track RNA in live cells. In a 2017 study in lab models and patient-derived cells, the researchers used RCas9 to eliminate 95 percent of the aberrant RNA linked to myotonic dystrophy type 1 and type 2, one type of ALS and Huntington's disease.

The current study advances RCas9 therapy further, reversing myotonic dystrophy type 1 in a living organism: a mouse model of the disease.

The approach is a type of gene therapy. The team packaged RCas9 in a non-infectious virus, which is needed to deliver the RNA-chewing enzyme inside cells. They gave the mice a single dose of the therapy or a mock treatment.

RCas9 reduced aberrant RNA repeats by more than 50 percent, varying a bit depending on the tissue, and the treated myotonic dystrophy mice became essentially indistinguishable from healthy mice.

Initially, the team was worried that the RCas9 proteins, which are derived from bacteria, might cause an immune reaction in the mice and be rapidly cleared away. So they tried suppressing the mice's immune systems briefly during treatment. As a result, they were surprised and pleased to discover that they prevented immune reaction and clearance, leaving the viral vehicle and its RCas9 cargo to persist, and get the job done. What's more, they did not see signs of muscle damage. In contrast, they saw an increase in the activity of genes involved in new muscle formation.

"This opens up the floodgates to start testing RNA-targeting CRISPR-Cas9 as a potential approach to treat other human genetic diseases -- there are at least 20 caused by buildup of repetitive RNAs," Yeo said.

It remains to be seen if RCas9-based therapies will work in humans, or if they might cause deleterious side effects, such as eliciting an undesired immune reaction. Preclinical studies such as this one will help the team work out potential toxicities and evaluate long-term exposure.

In 2017, Yeo co-founded a company called Locanabio to accelerate the development of RNA-targeting CRISPR-Cas9 through preclinical testing and into clinical trials for the treatment of myotonic dystrophy and potentially other diseases.

A research collaboration between Monash University and Lava Therapeutics details a novel immune-oncology approach for the potential treatment of cancer. Instrumental to the study was co-first author Dr Roeland Lameris from Amsterdam UMC and colleagues from the University of Melbourne.

Published in Nature Cancer, the study, co-led by Monash Biomedicine Discovery Institute's ARC Laureate Fellow Professor Jamie Rossjohn and Dr Adam Shahine, highlights the synergy between an antibody fragment, known as a nanobody, that not only acts as a bridge helping to link together two key immune cell receptors but also takes advantage of their interaction, enabling the body to enhance its immune response to cancer.

These antibody fragments, denoted as nanobodies, act by targeting the interaction between a molecule known as CD1d and Natural Killer T cells (NKT) in a stable and long-lasting manner, against tumour samples of patients with multiple myeloma and acute myeloid leukemia.

The new findings will serve as a model for the potential generation of new and effective therapies against a broad range of cancers.

Using the Australian Synchrotron, the team at Monash University provided detailed atomic insight into how the nanobodies exerted their effect on immune cells in a cancer model. "We were able to precisely visualise how the nanobody simultaneously recognised CD1d and the NKT TCR, thereby providing a molecular basis for their anti-tumour properties," Professor Rossjohn stated.

Hans van der Vliet, professor in medical oncology at Amsterdam UMC and chief scientific officer of Lava Therapeutics, says "By targeting and boosting natural immune cells that are inherent in all humans, such as NKT cells and gamma-delta T cells, for an enhanced therapeutic effect, we believe our approach could ultimately translate into a broadly applicable immunotherapeutic approach for a range of cancer indications."

"This collaborative work paves the way for rationally developing improved therapeutics to treat a range of cancers" said co-first author Dr Shahine.

About the Monash Biomedicine Discovery Institute at Monash University

Committed to making the discoveries that will relieve the future burden of disease, the newly established Monash Biomedicine Discovery Institute at Monash University brings together more than 120 internationally-renowned research teams. Spanning six discovery programs across Cancer, Cardiovascular Disease, Development and Stem Cells, Infection and Immunity, Metabolic Disease and Obesity, and Neuroscience, Monash BDI is one of the largest biomedical research institutes in Australia. Our researchers are supported by world-class technology and infrastructure, and partner with industry, clinicians and researchers internationally to enhance lives through discovery.

WESTMINSTER, Colorado - September 14, 2020 - Synthetic auxin products have given growers an important option for managing weed populations resistant to glyphosate and other herbicides. But according to an article featured in the journal Weed Technology, there is one important downside to dicamba, 2,4-D and other synthetic auxins. They often move off-target and can cause severe injury to sensitive plants growing nearby.

Complaints about the issue persist, despite the introduction of products reported to have reduced volatility. For this reason, researchers from the University of Wisconsin-Madison decided to take a close look at factors that might influence synthetic auxin volatility and soybean injury, especially as it applies to the relationship between glyphosate and synthetic auxins commonly used in corn.

Their study found that four out of seven commercial formulations of dicamba and 2,4-D became highly acidic when mixed with glyphosate, which increased their potential for volatility. Glyphosate was shown to have a greater impact on pH than any other spray component or additive.

Among their other significant findings: High temperatures and low wind speeds in the 48 hours after a synthetic auxin application were found to result in greater injury to susceptible soybean plants. Dicamba was found to produce greater injury than 2,4-D. In addition, application of dicamba formulations late in the growing season were found to produce similar levels of soybean injury as applications made early in the season.

Humankind is reliant on the ammonium in synthetic fertiliser for food. However, producing ammonia from nitrogen is extremely energy-intensive and requires the use of transition metals.

Researchers from Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany, have now achieved the conversion of nitrogen to ammonium at room temperature and low pressure without the need for transition metals. This was reported by a research group led by JMU scientist Holger Braunschweig in the journal Nature Chemistry.

A new toolbox for binding nitrogen

The industrial production of ammonia, the so-called Haber-Bosch process, requires high temperatures and pressures, and is estimated to consume roughly two percent of all energy produced on earth. This process also relies on transition metal elements, relatively heavy and reactive atoms.

In 2018, Professor Braunschweig's team reported the binding and chemical conversion of nitrogen using a molecule constituted only of lighter, non-metal atoms. A year later, they used a similar system to demonstrate the first combination of two nitrogen molecules in the laboratory, a reaction that had otherwise only been seen in Earth's upper atmosphere and under plasma conditions.

The key in both of these discoveries was the use of boron, the fifth lightest element, as the atom to which the nitrogen binds. "After these two discoveries, it was clear that we had a pretty special system on our hands," says Braunschweig.

Just add water

Although their system binds and converts nitrogen, only half of the puzzle pieces were in place. "We knew that completing the conversion of nitrogen to ammonia would be a major challenge, as it requires a complex sequence of chemical reactions that are often incompatible with each other," explains the JMU professor.

The breakthrough came from the most simple of reagents: traces of water left behind in a sample were enough to promote a sequential reaction that brought the team only a single step away from the target ammonium. It was later discovered that the key reactions could be done using a solid acid, allowing the reactions to occur sequentially in a single reaction flask, all at room temperature.

Making ammonium with beer

Realising that the acidification step of the process appeared to work even with simple reagents such as water, the team repeated the reaction using locally brewed Würzburger Hofbräu beer. To their delight, they were able to detect the pre-ammonium product in the reaction mixture.

"This experiment was in part a bit of fun, but it also shows how tolerant the system is to water and other compounds," explains Dr. Marc-André Légaré, the postdoctoral researcher who initiated the study. "The reduction of nitrogen to ammonia is one of the most important chemical reactions for mankind. This is undoubtedly the first time it has been done using beer, and it is particularly fitting that it was done in Germany!" says Dr. Rian Dewhurst, Akademischer Oberrat and coauthor of the study.

Much work left to be done

The reaction, while exciting, is still far from being a truly practical process for industrially producing ammonium. Ideally, finding a way to re-form the active species will be needed to make the process energy efficient and economical.

Nevertheless, the discovery is an exciting demonstration that the lighter elements can tackle even the biggest challenges in chemistry. "There is much left to be done here, but boron and the other light elements have already surprised us so many times. They are clearly capable of so much more," says Holger Braunschweig.

Scientists have discovered an elegant way of manipulating light using a "synthetic" Lorentz force -- which in nature is responsible for many fascinating phenomena including the Aurora Borealis.

A team of theoretical physicists from the University of Exeter has pioneered a new technique to create tuneable artificial magnetic fields, which enable photons to mimic the dynamics of charged particles in real magnetic fields.

The team believe the new research, published in leading journal Nature Photonics, could have important implications for future photonic devices as it provides a novel way of manipulating light below the diffraction limit.

When charged particles, like electrons, pass through a magnetic field they feel a Lorentz force due to their electric charge, which curves their trajectory around the magnetic field lines.

This Lorentz force is responsible for many fascinating phenomena, ranging from the beautiful Northern Lights, to the famous quantum-Hall effect whose discovery was awarded the Nobel Prize.

However, because photons do not carry an electric charge, they cannot be straightforwardly controlled using real magnetic fields since they do not experience a Lorentz force; a severe limitation that is dictated by the fundamental laws of physics.

The research team have shown that it is possible to create artificial magnetic fields for light by distorting honeycomb metasurfaces -- ultra-thin 2D surfaces that are engineered to have structure on a scale much smaller than the wavelength of light.

The Exeter team were inspired by a remarkable discovery ten years ago, where it was shown that electrons propagating through a strained graphene membrane behave as if they were subjected to a large magnetic field.

The major drawback with this strain engineering approach is that to tune the artificial magnetic field one is required to modify the strain pattern with precision, which is extremely challenging, if not impossible, to do with photonic structures.

The Exeter physicists have proposed an elegant solution to overcome this fundamental lack of tunability.

Charlie-Ray Mann, the lead scientist and author of the study, explains: "These metasurfaces, support hybrid light-matter excitations, called polaritons, which are trapped on the metasurface.

"They are then deflected by the distortions in the metasurface in a similar way to how magnetic fields deflect charged particles.

"By exploiting the hybrid nature of the polaritons, we show that you can tune the artificial magnetic field by modifying the real electromagnetic environment surrounding the metasurface."

For the study, the researchers embedded the metasurface between two mirrors -- known as a photonic cavity -- and show that one can tune the artificial magnetic field by changing only the width of the photonic cavity, thereby removing the need to modify the distortion in the metasurface.

Charlie added: "We have even demonstrated that you can switch off the artificial magnetic field entirely at a critical cavity width, without having to remove the distortion in the metasurface, something that is impossible to do in graphene or any system that emulates graphene.

"Using this mechanism you can bend the trajectory of the polaritons using a tunable Lorentz-like force and also observe Landau quantization of the polariton cyclotron orbits, in direct analogy with what happens to charged particles in real magnetic fields.

"Moreover, we have shown that you can drastically reconfigure the polariton Landau level spectrum by simply changing the cavity width."

Dr Eros Mariani, the lead supervisor of the study, said: "Being able to emulate phenomena with photons that are usually thought to be exclusive to charged particles is fascinating from a fundamental point of view, but it could also have important implications for photonics applications.

"We're excited to see where this discovery leads, as it poses many intriguing questions which can be explored in many different experimental platforms across the electromagnetic spectrum."

When NASA's Aqua satellite passed over the Eastern Pacific Ocean, it gathered water vapor data on Tropical Storm Karina. The data showed that the storm was being affected by wind shear from the northeast, pushing the bulk of clouds to the southwest.

Karina formed late on Saturday, Sept. 12 as Tropical Depression 16E (TD16E). TD16E developed about 470 miles (755 km) south-southwest of the southern tip of Baja California, Mexico. Six hours later at 5 a.m. EDT on Sept. 13, the depression organized and strengthened into a tropical storm and was renamed Karina.

A Look at Water Vapor Content

Water vapor analysis of tropical cyclones tells forecasters how much potential a storm has to develop. Water vapor releases latent heat as it condenses into liquid. That liquid becomes clouds and thunderstorms that make up a tropical cyclone. Temperature is important when trying to understand how strong storms can be. The higher the cloud tops, the colder and stronger the storms.

On Sept. 14 at 6:05 a.m. EDT (1005 UTC), NASA's Aqua satellite passed over Tropical Storm Karina in the Eastern Pacific Ocean. The Moderate Resolution Imaging Spectroradiometer or MODIS instrument gathered water vapor content and temperature information and found highest concentrations of water vapor and coldest cloud top temperatures were southwest of the center. That is because of strong northeasterly wind shear pushing the strong storms away from the center of circulation.

MODIS data showed coldest cloud top temperatures in those storms were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius) in those storms. Storms with cloud top temperatures that cold have the capability to produce heavy rainfall.

"Karina continues to be a sheared cyclone with the deep convection displaced to the southwest of the exposed low-level center," noted Jack Beven, a senior hurricane specialist at NOAA's National Hurricane Center in Miami. "Recent scatterometer [instrument that analyzes winds] data showed winds up to 40 knots in the southern semicircle, and thus the initial intensity remains 40 knots."

Wind Shear Affecting Karina

The shape of a tropical cyclone provides forecasters with an idea of its organization and strength. When outside winds batter a storm, it can change the storm's shape. Winds can push most of the associated clouds and rain to one side of a storm.

In general, wind shear is a measure of how the speed and direction of winds change with altitude. Tropical cyclones are like rotating cylinders of winds. Each level needs to be stacked on top each other vertically in order for the storm to maintain strength or intensify. Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels.

Karina's Status on Sept. 14

At 5 a.m. EDT (2 a.m. PDT/0900 UTC), the center of Tropical Storm Karina was located near latitude 17.9 degrees north and longitude 118.2 degrees west. Karina is centered 640 miles (1,025 km) west-southwest of the southern tip of Baja California, Mexico.  Karina is moving toward the west near 13 mph (20 kph). Maximum sustained winds are near 45 mph (75 kph) with higher gusts. Tropical-storm-force winds extend outward up to 150 miles (240 km) from the center. The estimated minimum central pressure is 1001 millibars.

Karina's Forecast

A turn toward the northwest is expected by tonight, Sept. 14, with this motion continuing for the next few days. Some slight strengthening is forecast in the next 24 hours, with gradual weakening expected to begin on Tuesday.

ORLANDO, Sept. 14, 2020 - A University of Central Florida researcher is co-author of a new paper that may help answer why some animals have a magnetic "sixth" sense, such as sea turtles' ability to return to the beach where they were born.

The question is one that has been unresolved despite 50 years of research.

"The search for a mechanism has been proposed as one of the last major frontiers in sensory biology and described as if we are 'searching for a needle in a hay stack,'" says Robert Fitak, an assistant professor in UCF's Department of Biology, part of UCF's College of Sciences.

Fitak and researchers in the United Kingdom and Israel recently authored an article in Philosophical Transactions of the Royal Society B that proposes a hypothesis that the magnetic sense comes from a symbiotic relationship with magnetotactic bacteria.

Magnetotactic bacteria are a special type of bacteria whose movement is influenced by magnetic fields, including the Earth's.

Animals that sense Earth's magnetic field include sea turtles, birds, fish and lobsters. Sea turtles, for example, can use the ability for navigation to return to the beach where they were born.

Learning how organisms interact with magnetic fields can improve humans' understanding of how to use Earth's magnetic fields for their own navigation purposes. It can also inform ecological research into the effects of human modifications of the magnetic environment, such as constructing power lines, on biodiversity. Research into the interaction of animals with magnetic fields can also aid the development of therapies that use magnetism for drug delivery.

In the article, the researchers review the arguments for and against the hypothesis, present evidence published in support that has arisen in the past few years, as well as offer new supportive evidence of their own.

Their new evidence comes from Fitak, who mined one of the largest genetic databases of microbes, known as the Metagenomic Rapid Annotations using Subsystems Technology database, for the presence of magnetotactic bacteria that had been found in animal samples.

Previous microbial diversity studies have often focused on large patterns of the presence or absence of bacteria phyla in animals rather than specific species, Fitak says.

"The presence of these magnetotactic bacteria had been largely overlooked, or 'lost in the mud' amongst the massive scale of these datasets," he says.

Fitak found, for the first time, that magnetotactic bacteria are associated with many animals, including a penguin species, loggerhead sea turtles, bats and Atlantic right whales.

For instance, Candidatus Magnetobacterium bavaricum regularly occurred in penguins and loggerhead sea turtles, while Magnetospirillum and Magnetococcus regularly occurred in the mammal species brown bats and Atlantic right whales.

Fitak says researchers still don't know where in the animal that the magnetotactic bacteria would live, but it could be that they would be associated with nervous tissue, like the eye or brain.

"I'm working with the co-authors and local UCF researchers to develop a genetic test for these bacteria, and we plan to subsequently screen various animals and specific tissues, such as in sea turtles, fish, spiny lobsters and birds," Fitak says.

Before joining UCF in 2019, Fitak worked for more than four years as a postdoctoral researcher at Duke University performing experiments to identify genes related to a magnetic sense in fish and lobsters using modern genomic techniques.

He says the hypothesis that animals use magnetic bacteria in a symbiotic way to gain a magnetic sense warrants further exploration but still needs more evidence before anything conclusive can be stated.

In recent years, the Pine Island Glacier and the Thwaites Glacier on West-Antarctica has been undergoing rapid changes, with potentially major consequences for rising sea levels. However, the processes that underlie these changes and their precise impact on the weakening of these ice sheets have not yet been fully charted. A team of researchers including some from TU Delft have now investigated one of these processes in detail: the emergence and development of damage/cracks in part of the glaciers and how this process of cracking reinforces itself. They are publishing about this in PNAS.

Satellite imagery

The researchers have combined satellite imagery from various sources to gain a more accurate picture of the rapid development of damage in the shear zones on the ice shelves of Pine Island and Thwaites. This damage consists of crevasses and fractures in the glaciers, the first signs that the shear zones are in the process of weakening. Modelling has revealed that the emergence of this kind of damage initiates a feedback process that accelerates the formation of fractures and weakening.

Unstable

According to the researchers, this process is one of the key factors that determines the stability - or instability- of the ice sheets, and thus the possible contribution of this part of Antarctica to rising sea levels. They are calling for this information to be taken into account in climate modelling, in order to improve predictions of the contribution these glaciers are making to rising sea levels.

As they roam around the African savanna in search for food, giraffes and elephants alter the diversity and richness of its vegetation. By studying the foraging patterns of these megaherbivores across different terrains in a savanna in Kenya, scientists from the Smithsonian Tropical Research Institute (STRI) and collaborating institutions discovered that these large mammals prefer to eat their meals on flat ground, potentially impacting the growth and survival of plant species on even savanna landscapes, such as valleys and plateaus.

Megaherbivores are more concerned about eating as much food as possible while expending the minimum amount of effort, than about avoiding potential predators. Elephants may consume as much as 600 pounds of vegetation in a day; giraffes, about 75. This drove scientists to wonder about the impact of these megaherbivores on vegetation across a range of landscapes in the savanna.

"Previous studies have demonstrated that megaherbivores adjust their movement patterns to avoid costly mountaineering," said co-author David Kenfack, STRI staff scientist, coordinator of the ForestGEO network forest monitoring plots in Africa and recently elected Fellow of the African Academy of Sciences. "We wanted to know the extent to which fine-scale variations in topography may influence browsing damage by these charismatic megaherbivores and evaluate whether seasonal shortages in food availability would force the megaherbivores to venture into areas with rugged terrain."

Their observations conducted within a 120-hectare Smithsonian ForestGEO long-term vegetation monitoring plot located at Mpala Research Center in Kenya confirmed that giraffes and elephants prefer flat ground while foraging. They compared the damage on Acacia mellifera trees, which grow all over the savanna landscape and are a common meal for megaherbivores. They found that the trees growing on steep slopes were taller and had fewer stems than those in valleys and plateaus, suggesting that elephant and giraffes tend to avoid feeding in these less accessible habitats.

This behavior did not change during the dry season, when resources become scarce, indicating that these two species would rather disperse to new areas with more favorable conditions than climb up a nearby slope to feed.

For the authors, these feeding patterns may help preserve steep slopes as habitat refugia, with a greater diversity and density of vegetation than more frequently visited areas. Their findings support this argument: the number and variety of trees encountered on the steep slopes was higher than in the valleys and plateaus.

"This study has broadened our understanding of the role of topography in explaining diversity patterns of plants," said Duncan Kimuyu, a Smithsonian Mpala postdoctoral fellow, lecturer at Karatina University in Kenya and main author of the study. "Further research is warranted to understand how other factors such as differences in soil properties may interact with topography and megaherbivores to influence the growth and survival of vegetation in the African savanna."

Many of the most common diseases -- cancer, diabetes, cardiovascular and lung disease, and even COVID-19 -- have been linked to chronic or excessive inflammation. Blood tests can indicate that some part of a person's body is inflamed, but doctors don't have a good way to zero in on the site of inflammation and visualize the problem to help them choose the best course of action.

Now, researchers at Washington University School of Medicine in St. Louis have developed an experimental imaging agent that illuminates the location and the intensity of inflammation. The agent, known as Galuminox, has shown promise in imaging inflammation in the lungs of mice with acute lung injury, the researchers report in Redox Biology.

The agent is designed to detect inflammation via positron-emission tomography (PET) scans. Such scans are not invasive, so they could be performed repeatedly to monitor a patient's response to anti-inflammatory medication or to track the development of inflammation in chronic diseases.

"Doctors don't have a good way to image inflammation at earliest stages, which can hamper the diagnosis and treatment of disease. We focused on lung injury in this paper, but in principle, this tracer could be applied to other conditions where you have inflammation: atherosclerosis, cardio- and pulmonary toxicity caused by chemotherapy, transplant rejection, you name it," said senior author Vijay Sharma, PhD, a professor of radiology at the university's Mallinckrodt Institute of Radiology (MIR) and a professor of neurology and of biomedical engineering. "If we had approval today, this tracer could even be used for COVID-19. The kinds of scans doctors can do right now on COVID patients' lungs tell you whether there is inflammation there but not how bad it is. A tracer like this could give doctors more information to make clinical decisions."

Inflammation is how the immune system responds to infection or injury. Immune cells become activated, and some produce toxic molecules called reactive oxygen species that destroy bacteria and viruses. Sometimes inflammation does not resolve after the initial threat is eliminated. Such persistent inflammation has been linked to chronic diseases ranging from asthma to cancer, but there are no imaging agents approved by the Food and Drug Administration specifically targeting the molecular signs of inflammation.

To fill this gap, Sharma and colleagues created Galuminox, a chemical compound that detects reactive oxygen species, and linked it to gallium-68, a radioactive metal. The production of reactive oxygen species indicates inflammation and has been associated with the development of many acute and chronic diseases. The resulting imaging agent gives off a radioactive signal in the presence of reactive oxygen species that can be visualized by PET scan.

To assess the potential use of the imaging agent in a disease setting, co-author Andrew Gelman, PhD, a professor of surgery, and colleagues modeled acute respiratory distress syndrome, a leading cause of intensive care death that can rapidly develop in patients with little to no warning. To do this, they injected mice with lipopolysaccharide, a molecule that stimulates reactive oxygen species production and is a component of many types of bacteria known to cause this disease.

PET scans revealed that the imaging agent was concentrated in the lungs of mice that had received lipopolysaccharide, and higher retention in lungs correlated with measurements of poor pulmonary function associated with this disease.

"Visualizing reactive oxygen species generation should us allow us to better define patterns of tissue damage easily," Gelman said. "This tracer could help us assess changes in reactive oxygen species generation over the course of a disease progression, which would provide clinicians better information on when it's best to start and suspend therapy. Until now, we haven't had a tool to do that."

All PET tracers include a radioactive component that decays quickly, so the radioactive part must be made on site just before use. In general, this means that a hospital or research center that wants to do PET scanning needs to have access to a multimillion-dollar cyclotron to produce the radioactive components on demand. As a metal, however, gallium-68 can be produced with only a generator, which costs closer to $50,000, making it potentially affordable for sites with limited imaging budgets.

The researchers are now studying whether Galuminox can be used to study diseases characterized by chronic inflammation, such as lung transplant failure.

"Almost everyone who gets a lung transplant eventually ends up with transplant rejection, and we think it has to do with reactive oxygen species," Gelman said. "The typical lung transplant only lasts about five to six years. We think that a lot of the irreversible changes in the lungs occur before the patient has symptoms. By the time they start having difficulty breathing, it may be too late for effective treatment. If we could detect signs of inflammation early, we might be able to intervene at an earlier stage and extend the life span of the transplant. That's what we're looking at now."

In Southeast Asia, wildlife trade is running rampant, and Vietnam plays a key role in combating wildlife trafficking.

Since the country opened its market to China in the late 1980s, a huge amount of wildlife and its products has been transported across the border every year. Species have also been exported to other Asian countries, Europe and the USA. Furthermore, in recent years, Vietnam has also supported the transit of pangolin scales and other wildlife products from across Asia and even as far as Africa all the way to China and other destinations.

Additionally, in line with the expanding wealthy middle class, consumption of wildlife and its products has risen dramatically in Vietnam. As a consequence, the country takes on all three major roles in the international wildlife trade: export, transit and consumption.

Freshwater turtles and tortoises make up a large part of the international trade between Vietnam and China and the domestic trade within Vietnam. Meanwhile, due to the increasing use of social networks, wildlife trade is shifting to online-based platforms, thereby further facilitating access to threatened species. Consequently, the Vietnamese pond turtle and the Swinhoe's softshell turtle, for example, are already on the brink of extinction. Despite the repeated recent survey efforts of conservation biologists, no viable populations of their species have been found.

One of the effective approaches to the conservation of the most endangered species is to have confiscated animals released back into the wild, following the necessary treatment and quarantine, or transferring them to conservation breeding programmes. However, in either of the cases, it is necessary to know about the origin of the animals, because the release of individuals at sites they are not naturally adapted to, or at localities inhabited by populations of incompatible genetic makeup can have negative effects both on the gene pool and ecosystem health.

In the present research article, published in the peer-reviewed open-access scientific journal Nature Conservation, turtle conservationist and molecular biologist Dr. Minh D. Le of Vietnam National University (Hanoi) and the American Museum of Natural History (New York), in collaboration with the Cologne Zoo (Germany) and the Asian Turtle Program - Indo-Myanmar Conservation (Hanoi), the Institute of Ecology and Biological Resources (Hanoi) and Hanoi Procuratorate University (Hanoi), studies the geographic distribution of genetic diversity of the endangered Four-eyed turtle (Sacalia quadriocellata). The species, whose common name relates to the four eye-resembling spots, located on the back of its head, has traditionally been neglected by scientific and conservation efforts.

Having analysed field-collected and local trade samples along with confiscated animals, the researchers concluded that there is a significant number of genetically distinct lineages distributed in Vietnam and China, and that local trade samples could provide key data for resolving the genetic patterns of the species. They remind that Four-eyed turtles are getting more and more difficult to find in the wild.

On the other hand, the study highlights that confiscated animals are of various origin and, therefore, must not be released arbitrarily where they have been seized. Instead, the researchers recommend that captive programmes establish regular genetic screenings to determine the origin of confiscated turtles, so that the risk of crossing different lineages is eliminated. Such genetic screenings are of crucial importance to solve the current issues with biodiversity conservation in the country and the region.

"Like other developing countries, Vietnam does not have any specific guidelines on how to release confiscated animals back into the wild yet. This and other similar studies emphasise the role of the government in the implementation of stricter laws and regulation," said Dr. Minh D. Le, lead author of the study.

"This research once more underscores the IUCN's One Plan Approach, which aims to develop integrative strategies to combine in situ and ex situ measures with expert groups, for the purposes of species conservation," added Dr. Thomas Ziegler of the Cologne Zoo.