Tech

Philadelphia, September 23, 2020 - Depression in elderly people can include symptoms such as memory loss, making it hard to distinguish from the early stages of Alzheimer's disease and other types of dementia. A signature of Alzheimer's is accumulation of a protein called amyloid beta (Aβ) in the brain, which can be detected with brain-imaging technology.

Researchers had suspected that Aβ deposits might also underlie the cognitive decline seen in older people with depression, however a new study from researchers at the University of California, San Francisco (UCSF) has found that abnormal Aβ deposits were actually found in fewer older adults with major depression compared to non-depressed control subjects. The study, appears in Biological Psychiatry, published by Elsevier.

John Krystal, Editor of Biological Psychiatry, said of the work: "In the elderly, depression can sometimes be difficult to tease apart from dementia. This important study finds that late-life depression was not associated with increased deposition of beta-amyloid in the brain, a hallmark of Alzheimer's disease. This insight is important, because tests - like the PET scans that enable detection of deposited amyloid - may someday play a role in helping doctors to make this distinction."

The study included 119 older adults with major depression and 119 non-depressed participants with an average age of 71. All of the depressed participants were enrolled in the Alzheimer's Disease Neuroimaging Initiative's Depression (ADNI-D) Project , a large research collaboration between multiple research agencies and universities. None of the participants in the current study had been diagnosed with dementia. The researchers collected blood and DNA samples from the subjects, and they used positron emission tomography (PET) to detect Aβ deposits in their brains.

"Surprisingly, we did not observe evidence of increased amyloid deposition in the participants with major depression," said Principal Investigator and lead author Scott Mackin, PhD, and professor of Psychiatry at the UCSF Weill Institute for Neurosciences, San Francisco, CA, USA. "Instead, we saw decreased amyloid deposition when we compared the groups in several different ways."

Significant amyloid protein deposits were detected in just 19 percent of participants with depression compared with 31 percent of control subjects.

As expected, subjects with depression performed worse on cognitive and memory tests than non-depressed subjects. In addition, participants with brain amyloid deposits performed worse on the memory tests, but this was true regardless of whether they had depression or not. "Depression had a strong impact on memory performance independent of amyloid deposition," Dr. Mackin said.

Together, the findings indicate that depression is a risk factor for cognitive decline, but that it probably works through some mechanism other than amyloid deposition.

The presence of amyloid deposits did not depend on a patient's history of depression or use of anti-depressant treatments, which, Dr. Mackin said, "would suggest that depressed mood, or depression treatments, are also likely not protective against amyloid deposition."

According to the authors, the findings generated many new questions that will need to be investigated.

Many animal species are currently changing their distribution range owing to global warming. The underlying mechanisms are still little known, especially in mammals. An international team of scientists led by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) has now demonstrated that in the common noctule bat, one of the largest European bat species, the colonization of hibernacula progresses from lower to higher latitudes over successive generations of young animals - especially first-year males. Because of their relatively high reproduction rate and the long-distance dispersal of male juveniles, it is probably relatively easy for common noctules to adjust to global warming. For species with lower reproduction rates and a limited migratory potential of the young - the majority of European bat species - the future might not look as favourable when facing continuing global warming. The paper was published in the scientific journal "Biology Letters".

The rapid pace of global warming is forcing animals to adjust their lives to ensure their survival and successful reproduction. Highly mobile species such as migratory bats could potentially shift their summer and wintering habitats to higher or lower latitudes according to how the regional climate is changing. This flexibility could enable migratory bats to stay within ideal conditions for reproducing and rearing of young or for hibernation. For example, in recent years common noctule bats have shifted their wintering area further north. Is this shift in the wintering range the consequence of adult bats moving further north for hibernation year after year, or are these shifts done by juvenile bats from successive generations? Scientists of the Leibniz-IZW and partners from the Ukraine - the "Bat Rehabilitation Center of Feldman Ecopark" and the "Ukrainian Independent Ecology Institute" - addressed this question in a long-term study.

"We showed that the northwards move of the hibernation area of the common noctule occurs over several generations of juveniles", says Christian Voigt, head of the Department of Evolutionary Ecology at Leibniz-IZW. "Especially young males, which usually migrate further from their birthplace than young females, are leading the way when colonising new hibernacula". Since common noctules have a short life span, a high reproduction rate and can disperse over long distances, they may be able to adjust relatively quickly to global warming, even if the wintering area only successively changes from generation to generation.

The investigation was carried out in the city of Kharkiv in northern Ukraine. Maternity colonies of common noctule females were long recorded north of the Kharkiv area, with hibernating animals moving to areas well south of Kharkiv. Then, 30 years ago the first individuals were encountered who hibernated further north close to Kharkiv, with increasing numbers of hibernating bats nearby since then. Over a ten-year period, the scientists collected data on the age and sex of almost 3,400 individuals. These data showed that young males dominated the early phase of colonisation of the new hibernation area. Gradually, the ratio of males to females and of young to adult animals became more balanced. "We also investigated the region of origin of the hibernating common noctules by analysing stable hydrogen isotopes in the fur keratin", says Kseniia Kravchenko from Leibniz-IZW, the first author of the paper. "The data of nearly 400 animals revealed that the number of long-distance migrants decreased in both females and males across all age groups". This showed that in the early years of colonisation the hibernation population originated from summer quarters in the far north. More recently, the "local" population with summer quarters nearby, who previously had flown further south for hibernation, increasingly used the same area as their summer quarters for reproduction and for wintering.

The rapid generational shift and the high dispersal capacity of young males seem to be an evolutionary advantage of common noctule bats in times of climate change, the authors conclude. "Mammal species with higher life expectancies, lower reproductive rate and lower dispersal capacity may have a much harder time in keeping up with the pace of global warming", suspect Kravchenko and Voigt. "If the distribution areas of these species only shift from generation to generation, the pace may be too slow and there is a chance that they will become extinct if global warming continues at the current high pace." Further research will be necessary to understand these mechanisms of spatial adjustment to climate change in other mammalian species.

With the development of society, energy demand increases. A series of problems caused by the excessive use of fossil fuel requires clean renewable energy for sustainable development. However, the intermittent and random nature of renewable energy generation such as wind and solar power brings challenges to the safe and stable operation of the power grid. As a key technology for the wide application of renewable energy, large-scale energy storage technology can effectively solve the above problems. Flow batteries are one of the most promising large-scale energy storage technologies due to their attractive features of high safety, high efficiency and long cycle life. The vanadium flow battery (VFB) is one of the mature technologies and now at the stage of commercial demonstration. Nonetheless, their further development is restricted by the relatively high cost and low energy density. Therefore, the investigation of novel flow battery systems with high energy density and low cost is essential to the sustainable development of flow batteries. Recently, fast-growing interests in organic redox-active materials are found due to their advantages of resource sustainability, potentially low cost, and chemical tunability.

Various organic flow batteries based on quinone, ferrocene, TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy), viologen, phenazine, phenothiazine have been investigated by the structural design over the past decades. Up to now, most of the organic molecules show low redox potential and therefore have been explored as anodes. Only a few molecules display relatively high potential and can be used as cathodes. However, most of them show poor chemical and electrochemical stability. Therefore, the existing organic flow battery systems can normally be operated stably under an N2 or Ar atmosphere. Recently, researchers from the Dalian Institute of Chemical Physics reported an air-insensitive low-cost biphenol derivative (3,3',5,5'-tetramethylaminemethylene-4,4'-biphenol (TABP)) cathode with high potential and solubility. The TABP is prepared via a simple one-step method. Paring with silicotungstic acid (SWO), an SWO/TABP flow battery shows a stable cycling performance of zero capacity decay over 900 cycles under the air atmosphere. Further, an SWO/TABP flow battery demonstrates a high rate performance with an energy efficiency of 85% and 73% at 60 and 120 mA cm-2, respectively. Also, a high practical discharge capacity of more than 47 Ah L-1 based on the 1 mol L-1 catholyte can be achieved. NMR tests and DFT calculations confirm that the biphenol structure of the TABP molecule has excellent oxidation resistance by a larger ?-conjugated structure, and the four tertiary ammonium functional groups of TABP greatly improve the stability of the TABP by inhibiting the Michael addition reaction.

Fig. 1(a) is a schematic representation of the SWO/TABP flow battery and its cycling test under the air atmosphere at a current density of 40 mA cm-2. The battery shows zero capacity fade after continuously running for 900 cycles. To investigate the role of four substituted tertiary ammonium groups, the biphenol derivative with two substituted tertiary ammonium groups, 3,3'-dimethylaminemethylene-4,4'-biphenol (DABP), is synthesized for comparison. Fig. 1(b) shows 1H NMR spectra of TABP and DABP catholytes at different state of charges (SOCs). Comparing the spectra before and after the charge and discharge process, all peak positions show no change and no new peaks are generated, indicating the high reversibility of the charge and discharge process. In contrast, the NMR spectra of catholyte from DABP at different SOCs show obvious changes due to the irreversible side reactions. By DFT calculation, they calculated the potential energy surfaces of the Michael addition reaction of two biphenol derivatives, as shown in Fig. 1(c). The activation energy of TABP is much higher than DABP, which indicates the reaction between TABP and H2O is more difficult. The DFT results are consistent with the experimental results.

To further confirm the stability of the biphenol structure in the air, the air-stability test is performed and benzoquinone with four substituted tetra-tertiary ammonium (2,3,5,6-tetrakis((dimethylamino)methyl)hydroquinone (TABQ)) is synthesized for comparison. By comparing the stability of TABP and TABQ in the air, they found that TABQ is easily oxidized in the air, while TABP with a biphenol structure remains unchanged after standing in the air for more than 20 days.

The above results show that TABP with high solubility, potential and stability is a promising anode for the application of aqueous organic flow battery. This paper confirms the possibility of an organic-based flow battery for real practical application and offers new opportunities to develop low-cost and high-performance flow batteries that promise sustainable and green large-scale energy storage technologies. More details can be found in the reference articles as below.

According to a new review paper, published in Journal of The Electrochemical Society, industry leaders feel that battery safety standards do not represent real-world scenarios that could cause fires and are therefore not robust enough to prevent, detect, and suppress battery fires. The authors argue that better alignment of research and industry could address this gap and help to reduce the likelihood of and damage from battery fires.

Lithium-ion batteries power our smartphones, laptops, and many rechargeable gadgets. They are also a key technology for decarbonised sustainable energy and are used in electric vehicles and smart grids.

However, many types of lithium-ion battery display a tendency to ignite or release gases. Although statistically rare, battery fires can spread faster and last longer than other fires, release more toxic chemicals, and be harder to suppress.

The Imperial researchers say they worry that the most pressing safety problems faced by battery companies are not readily answered by the scientific research currently being conducted, and that several safety elements that can be added to batteries are not being considered because of this lack of integration between industry and research.

Senior author Dr Greg Offer of Imperial's Department of Mechanical Engineering said: "The popularity of these batteries is booming, and industry and scientists naturally share the common goal of producing safer batteries. However the distinction between their approaches mean that industry and research are not yet aligned enough make batteries as safe possible."

Differing approaches

In their review, the researchers collected views from a wide range of battery companies about the fire safety challenges they face, and analysed and compared them to top contributions to the field from scientific literature.

They found that battery companies were mainly concerned about battery safety, and the need for improved standards and regulations. While there are several recognised international standards for many industries of lithium-ion batteries, a major shared concern is that the available standards are not always representative of real-world scenarios. For example, regulations dictate that electric vehicles are tested using conditions derived from combustion engine regulations, and are therefore not representative of electric vehicles which use only electricity.

In addition, most current scientific research focuses on the prevention of fires, and the authors argue there is a lack of research focusing on detecting and suppressing them.

They also found that while industry tends to focus on specific questions at larger scales, like those of overall battery systems, research tends to focus on the fundamental understanding of smaller scale questions, like those of smaller components and cells.

Joint first author Xuanze He of Imperial's Department of Mechanical Engineering said: "This is problematic because lessons from laboratory studies on smaller components don't directly translate to large systems in real-world situations. We as researchers need to address this research gap by using larger-scale studies on battery safety - and we also need to collaborate more with industry."

Closing the gap

The researchers suggest that manufacturers pay more attention to how battery defects and accidents can lead to fire, and the roles of gas toxicity, early detection, novel suppression systems, and safe recycling of batteries.

Joint first author Laura Bravo, also of Imperial's Department of Mechanical Engineering, said: "Perhaps incorporating more real-world research like this into industry standards will help to close the gap between imagined and real-world fire safety scenarios."

The analysis provides several recommendations that could improve battery safety: firstly, that battery industries embrace more comprehensive fire protection strategies that integrate more safety layers, and secondly that closer collaboration between the battery and fire safety research communities could drive improvements, integration and harmonisation of fire safety across sectors.

Senior author Professor Guillermo Rein of the Department of Mechanical Engineering said: "Lithium-ion batteries are here to stay, so everyone wins when their safety improves. Bringing the battery and fire safety communities together sooner rather than later could prove crucial to solving lithium-ion battery safety issues."

Electrochemistry is playing an increasingly important role: Whether it is fuel cells, electrolysis or chemical energy storage, chemical reactions controlled by electric current are used. The decisive factor in all these applications is that the reactions are as fast and efficient as possible.

An important step forward has now been taken by a team from TU Wien (Vienna) and DESY in Hamburg: They showed that a special material made of lanthanum, strontium, iron and oxygen can be switched back and forth between two different states: In one state the material is catalytically extremely active, in the other less so. The reason for this is the behavior of tiny iron nanoparticles on the surface, which has now been demonstrated in experiments at the German Electron Synchrotron DESY in Hamburg. This finding should now make it possible to develop even better catalysts. The result has been published in the journal "Nature Communications".

Electrical voltage causes oxygen ions to migrate

"We have been using perovskites for our electrochemical experiments for years," says Prof. Alexander Opitz from the Institute of Chemical Technologies and Analytics. "Perovskites are a very diverse class of materials, some of them are excellent catalysts." The surface of the perovskites can help to bring certain reactants into contact with each other - or to separate them again. "Above all, perovskites have the advantage that they are permeable to oxygen ions. Therefore, they can conduct electric current, and we are taking advantage of this," explains Alexander Opitz.

When an electrical voltage is applied to the perovskite, oxygen ions are released from their place within the crystal and start to migrate through the material. If the voltage exceeds a certain value, this leads to iron atoms in the perovskite migrating as well. They move to the surface and form tiny particles there, with a diameter of only a few nanometers. Essentially, these nanoparticles are excellent catalysts.

"The interesting thing is that if one reverses the electric voltage, the catalytic activity decreases again. And so far the reason for this was unclear," says Alexander Opitz. "Some people suspected that the iron atoms would simply migrate back into the crystal, but that's not true. When the effect takes place, the iron atoms do not have to leave their place on the material surface at all."

Analysis with X-rays at DESY

The research team at TU Wien collaborated with a team at the Electron Synchrotron in Hamburg (DESY) to precisely analyze the structure of the nanoparticles with X-rays while the chemical processes take place. It turned out that the nanoparticles change back and forth between two different states - depending on the voltage applied: "We can switch the iron particles between a metallic and an oxidic state," says Alexander Opitz. The applied voltage determines whether the oxygen ions in the material are pumped towards the iron nanoparticles or away from them. This allows to control how much oxygen is contained in the nanoparticles, and depending on the amount of oxygen, the nanoparticles can form two different structures - an oxygen-rich one, with low catalytic activity, and an oxygen-poor, i.e. metallic one, which is catalytically very active.

"This is a very important finding for us," says Alexander Opitz. "If the switching between the two states were caused by the iron atoms of the nanoparticle diffusing back into the crystal, very high temperatures would be needed to make this process run efficiently. Now that we understand that the activity change is not related to the diffusion of iron atoms but to the change between two different crystal structures, we also know that comparatively low temperatures can be sufficient. This makes this type of catalyst even more interesting because it can potentially be used to accelerate technologically relevant reactions.

From hydrogen to energy storage

This catalytic mechanism is now to be further investigated, also for materials with slightly different compositions. It could increase the efficiency of many applications. "This is particularly interesting for chemical reactions that are important in the energy sector," says Alexander Opitz. "For example, when it comes to the production of hydrogen or synthesis gas, or to energy storage by producing fuel with electric current."

Until now, seven genes were known to be involved in hearing loss in Israel's Jewish population. A new study led by Zippora Brownstein, PhD, and Prof. Karen Avraham from the Sackler Faculty of Medicine at Tel Aviv University has found that 32 genes are responsible for inherited hearing loss in Israeli Jewish families. The researchers also identified a mutation in a gene not previously recognized to cause hearing loss in humans. The research has immediate implications for genetic counseling for families with hearing loss and for care of children with hearing loss.

Researchers from multiple Israeli universities and hospitals, and the University of Washington in Seattle, the U.S. National Institutes of Health (NIH), Bethlehem University, the University of Iceland, and the University of Maryland contributed to the study. The study was published on July 20, 2020, in the journal Clinical Genetics.

More than 150 genes are known to be involved in hearing loss. Genetic diagnoses for inherited hearing loss have previously been difficult because any one of these different genes, and any of many mutations in each gene, could be the cause. Until now, mutations in only seven of the 150 genes had been detected among persons with hearing loss in the Jewish population of Israel. In the current study, which included 88 Israeli families with hearing loss, the researchers identified mutations in 25 additional genes.

Although 24 of the 25 genes are known to cause hearing loss in families worldwide, most of the specific mutations in Israeli Jewish families are newly observed and thus far known only the Jewish community. The 25th gene, called ATOH1, was found for the first time to cause hearing loss in humans.

"We know that ATOH1 has an important role in the ear," explains Prof. Avraham. "Without it, hair cells of the inner ear -- the cells responsible for our hearing -- cannot develop properly. Until now, a mutation in this gene was identified only in mice, and the mice had a hearing loss. We found a similar mutation in relatives with hearing loss in a large family in Israel, the first people in the world known to have a mutation in this gene. I believe we will find more families, both in Israel and abroad, with mutations in this gene that cause hearing loss. With this information, new treatment possibilities, including gene therapy, for people with hearing loss will be developed.

"We surveyed Jewish families throughout Israel with all types of hearing loss: from congenital to older age at onset, and from moderate to profound," Prof. Avraham adds. "Our survey exploited advanced gene sequencing technology, including a custom gene panel that we created called HEar-Seq. This custom gene panel allowed us to simultaneously sequence all 150 genes known to be involved in hearing loss, and many 'candidate genes' as well. HEar-Seq revealed the distribution of genes and their mutations responsible for hearing loss in all the Jewish communities that make up modern Israel. It led us to ATOH1.

"Our discoveries have immediate implications for genetic counseling, which can enable families to prevent additional cases of hearing loss through pre-gestational genetic diagnosis and in-vitro fertilization. Also, for many families, treatment and rehabilitation for hearing loss can be tailored to the family's specific mutation. The findings of this study allow doctors and audiologists in Israel to provide personally tailored treatment to patients with inherited hearing loss."

A new type of imaging that does not require a lens and uses reconfigurable particle-based masks to take multiple shots of an object is being developed by researchers at Penn State. The electric-field directed self-assembling mask technology is expected to have uses in lower-cost and faster disease diagnosis, the enhancement of optical microscopy, and may even lead to thinner cellphone technology.

How it works

The researchers create a mask of microscopic gold wires and place it near the object that will be imaged. The mask scatters the light reflected off the object and an image sensor collects the light. An electric current rearranges the particles in the mask, producing a new mask with every iteration, and the system records each new image. The multiple light captures are then computationally reconstructed into the original object image, resulting in highly improved resolution and quality.

"We are not the only group to do lens-free imaging," explained Jennifer Miller, a doctoral candidate in chemistry and a first author on a paper recently published online in ACS Nano. "What is different about our work is that typically you would need to make multiple masks and physically move them around to get multiple images. This becomes bulky and expensive and negates some of the simplicity that is the advantage of lens-free imaging."

In typical microscopy, there exists a trade-off between the field of view and the power of the resolution, so a 10x field is wider than a100x field. By using a lens-free imaging technology, it is possible to combine a wide field of view with high magnification for lower-cost images and faster diagnosis of disease. This could be especially useful in developing countries where high-end microscopes are not available.

"Traditional masks are passive," said co-first author Cheng-Yu Wang, doctoral candidate in electrical engineering. "We can add functionalization to our microwire, like polarization, selectivity and plasmonic effects, that make our imaging system more powerful."

In the case of cellphones, one major contributor to their bulk is due to the camera lens needing to be a certain distance to the detector. A lens-free camera could help minimize the space requirement. Likewise, a lens-free system added to a cellphone could turn the cellphone into a low-power microscope.

Obstructive sleep apnea (OSA) is a chronic sleep condition affecting more than one billion people worldwide. Evidence suggests OSA can alter the gut microbiome (GM) and may promote OSA-associated co-morbidities, including diabetes, hypertension and cognitive problems. Researchers from the University of Missouri School of Medicine and MU Health Care have discovered how OSA-related sleep disturbances affect the gut microbiome in mice and how transplanting those gut bacteria into other mice can cause changes to sleep patterns in the recipient mice.

David Gozal, MD, the Marie M. and Harry L. Smith Endowed Chair of Child Health at the MU School of Medicine, said the study shows the gut microbiome plays a major role in sleep regulation. This ultimately could translate into treatments that target the gut microbiome in humans with OSA.

"By manipulating the gut microbiome, or the byproducts of the gut microbiota, we would be in a position to prevent or at least palliate some of the consequences of sleep apnea," said Gozal, the lead author of the study. "For example, if we combine continuous positive airway pressure (CPAP) with customized probiotics that change the patient's gut microbiome, we might be able to eliminate some of the tiredness and fatigue and reduce the likelihood of the comorbidities associated with OSA that affect cognition, memory, cardiovascular disease or metabolic dysfunction. If we can do any one of those things, then this is a major movement forward in the way we treat OSA."

The study exposed male mice to either room air or intermittent hypoxia -- a condition in which the body doesn't get enough oxygen -- designed to mimic OSA. After six weeks, researchers collected fecal material from all of the rodents. A third group of mice was divided up and given either a fecal transplant from the mice breathing room air or those exposed to intermittent hypoxia. The transplanted mice underwent sleep recordings for three consecutive days. Researchers found the mice who received transplants from the intermittent hypoxia group slept longer and slept more often during their normal period of wakefulness, suggesting increased sleepiness.

"This is the first study that evaluated sleep in naïve mice subjected to a fecal microbiome transplant from mice exposed to intermittent hypoxia," Gozal said. "The fecal microbiome analysis showed profile differences between the mice transplanted from intermittent hypoxia donor mice versus those exposed to room air, indicating that the transplant altered the GM of the recipient mice."

Emerging evidence suggests the GM can influence health and sleep quality through the brain-gut microbiome axis (BGMA). The next step is to study the mechanism involved in the relationship between the brain and the gut to determine how changes in the gut microbiome can affect sleep structure and, in turn, how OSA can contribute to co-morbidities.

Hurricane Teddy has transitioned to a large post-tropical cyclone over eastern Canada. Using a NASA satellite rainfall product that incorporates data from satellites and observations, NASA estimated Teddy's rainfall rates. In addition to the heavy rainfall, Teddy causing destructive waves and strong winds today, Sept. 23, for portions of Atlantic Canada.

Teddy made landfall in the Sheet Harbour area of Nova Scotia on the province's Eastern Shore around 7:30 a.m. EDT, Sept. 23.

Warnings and Watches in Effect on Sept. 23

NOAA's National Hurricane Center (NHC) issued warnings and watches for Teddy on Sept. 23. Tropical Storm Warning is in effect for the south coast of Nova Scotia from Digby to Meat Cove, and for Port aux Basques to Francois, Newfoundland, Canada.

A Tropical Storm Watch is in effect for Meat Cove to Tidnish, Nova Scotia, and from north of Digby to Fort Lawrence, Nova Scotia, and for the Magdalen Islands, Quebec and Prince Edward Island.

What is a Post-tropical and Extra-tropical Cyclone?

At 11 p.m. EDT on Sept. 22, U.S. Navy Hurricane Specialist Dave Roberts at the NHC said, "Extratropical transition has been ongoing since last night, with the cyclone's associated rain shield expanding over a great distance in the northern semicircle.  In addition, multiple dropsonde observations from the Air Force Reserve hurricane hunters and buoy data show a sharp temperature gradient of nearly 20 degrees F from northwest quadrant to the southeast, indicative of the cyclone's involvement with the strong baroclinic frontal zone. Accordingly, Teddy has become a strong post-tropical extratropical cyclone."

NHC defines a post-tropical cyclone as a former tropical cyclone. This generic term describes a cyclone that no longer possesses sufficient tropical characteristics to be considered a tropical cyclone. Post-tropical cyclones can continue carrying heavy rains and high winds. Former tropical cyclones that have become fully extratropical or remnant lows are both classes of post-tropical cyclones.

What does Extra-tropical Mean?

When a storm becomes extra-tropical it means that a tropical cyclone has lost its "tropical" characteristics. The National Hurricane Center defines "extra-tropical" as a transition that implies both poleward displacement (meaning it moves toward the north or south pole) of the cyclone and the conversion of the cyclone's primary energy source from the release of latent heat of condensation to baroclinic (the temperature contrast between warm and cold air masses) processes. It is important to note that cyclones can become extratropical and still retain winds of hurricane or tropical storm force.

Teddy's Status on Sept. 23

At 8 a.m. EDT (1200 UTC), the center of Post-Tropical Cyclone Teddy was located near latitude 44.8 degrees north and longitude 62.3 degrees west. That is 65 miles (105 km) east-northeast of Halifax, Nova Scotia, Canada. The post-tropical cyclone is moving toward the north-northeast near 23 mph (37 kph), and this motion, with an increase in forward speed, is expected for the next day or so.  On the forecast track, the center will move over eastern Nova Scotia soon, and then near or over Newfoundland by tonight, and be east of Labrador on Thursday.

Maximum sustained winds are near 65 mph (100 km/h) with higher, gusts.  Some weakening is forecast during the next day or so, but Teddy should remain a strong post-tropical cyclone while passing over Nova Scotia and near Newfoundland. Teddy is a huge storm. Tropical-storm-force winds extend outward up to 520 miles (835 km) from the center. The estimated minimum central pressure is 963 millibars.

Estimating Teddy's Rainfall Rates from Space

NASA's Integrated Multi-satellitE Retrievals for GPM or IMERG, which is a NASA satellite rainfall product, estimated on Sept. 23 at 3:30 a.m. EDT (0730 UTC) that Teddy was generating between 5 and 15 mm (0.20 and 0.60 inches) of rain per hour around the center of circulation. Rainfall throughout most of the storm was estimated as falling at a rate between 0.3 and 2 mm (0.01 to 0.08 inches) per hour.

At the U.S. Naval Laboratory in Washington, D.C., the IMERG rainfall data was overlaid on infrared imagery from NOAA's GOES-16 satellite to provide a full extent of the storm.

NHC Key Messages

The National Hurricane Center (NHC) issued three key messages about Teddy on Sept. 23:

Teddy is expected remain a powerful post-tropical cyclone while it moves near or over portions of Atlantic Canada through tonight. The most significant hazard expected from Teddy is large destructive waves forecast along the southern coast of Nova Scotia today.

Very large swells produced by Teddy are expected to affect portions of Bermuda, the Leeward Islands, the Greater Antilles, the Bahamas, the east coast of the United States, and Atlantic Canada during the next few days. These swells are expected to cause life-threatening surf and rip current conditions.

Tropical Storm Watches and Warnings are in effect for portions of Nova Scotia, Newfoundland, Prince Edward Island and the Magdalen Islands, and heavy rainfall across Atlantic Canada is expected through Thursday.

Teddy's Fate in the Atlantic

NHC Senior Hurricane Specialist Richard Pasch said, "Teddy's deep convection has been diminishing, but based on buoy observations the cyclone still has a strong circulation with a central pressure in the 950's (millibars).  Assuming a gradual spin down of the system since the earlier aircraft observations, the estimated maximum winds have dropped to just below hurricane strength.  The system is expected to traverse Nova Scotia today as a strong extratropical cyclone, and move near Newfoundland by tonight.  After passing east of Labrador on Thursday, the global models show Teddy merging with another large extratropical low over the north Atlantic."

What Does IMERG Do?

This near-real time rainfall estimate comes from the NASA's IMERG, which combines observations from a fleet of satellites, in near-real time, to provide near-global estimates of precipitation every 30 minutes. By combining NASA precipitation estimates with other data sources, we can gain a greater understanding of major storms that affect our planet.

What the IMERG does is "morph" high-quality satellite observations along the direction of the steering winds to deliver information about rain at times and places where such satellite overflights did not occur. Information morphing is particularly important over the majority of the world's surface that lacks ground-radar coverage. Basically, IMERG fills in the blanks between weather observation stations.

Skoltech researchers have designed and developed an interface that allows a user to direct a small drone to light-paint patterns or letters through hand gestures. The new interface, DroneLight, can be used in distant communications, entertainment, and even search and rescue: https://youtu.be/SdnIqLjtGeU. The paper was published on the preprint server arXiv.org and presented at IEEE International Conference on Robot & Human Interactive Communication (IEEE RO_MAN 2020).

Drones are becoming ubiquitous both in industrial and consumer applications, and engineers are working on ways to make human-drone interaction as natural and reliable as possible. Yet, as the paper notes, "up to now, the available technologies have not made it possible to control drones intuitively without special training and additional control equipment."

"Flight control is a challenging task as user has to manipulate with the joystick to stabilize and navigate drones. Only a very skillful operator can maintain smooth trajectory, such as drawing a letter, and for the typical user it is almost not possible," says Professor Dzmitry Tsetserukou, a coauthor of the paper.

Tsetserukou, Roman Ibrahimov, and Nikolay Zherdev with the Skoltech Intelligent Space Robotics Laboratory have developed a system that allows easy interaction with a micro-quadcopter with LEDs that can be used for light-painting. The researchers used a 92x92x29 mm Crazyflie 2.0 quadrotor that weighs just 27 grams, equipped with a light reflector and an array of controllable RGB LEDs.

The control system consists of a glove equipped with an inertial measurement unit (IMU; an electronic device that tracks the movement of a user's hand), and a base station that runs a machine learning algorithm. This algorithm matches the user's gestures to pre-defined letters or patterns and directs the drone to light-paint them. In their experiment, the engineers defined five different letters (S, K, O, L and J), training a Random Forest Classifier algorithm to connect the hand gestures for these letters to corresponding drone trajectories.

The team plans to further develop their system by adding more user gestures to the dataset, adding more letters to its 'alphabet', and creating a more precise and faster machine learning algorithm.

"The most fascinating application can be DroneMessenger, when partners can not only exchange messages and emoji over the distance but also enjoy the light art during a starry night. Another application is a show of drones when an operator can generate dynamic light patters in the sky in real time. You can also imagine another system, SwarmCanvas, where users located in remote places can draw a joint picture on the canvas of the night sky. Currently, drone show systems just reproduce predesigned trajectories and lighting patterns," Tsetserukou notes.

NASA's Terra satellite provided a visible image of a slightly elongated Tropical Storm Dolphin as it battled wind shear upon its approach to east central Japan.

A Visible Satellite Image

The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Terra satellite captured a visible image of Tropical Storm Dolphin on Sept. 23 at 12:30 a.m. EDT (0430 UTC). Dolphin appeared somewhat elongated from west to east likely from the strong vertical wind shear the storm has been battling.

However, despite the increasing vertical wind shear of 30 knots (35 mph/56 kph), animated multispectral satellite imagery shows that Dolphin is a consolidated system with strong thunderstorms banding and wrapping into the low-level circulation center.

Wind Shear Affecting Dolphin

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.

Dolphin on Sept. 23

On Sept. 23 at 5 a.m. EDT (0900 UTC). Tropical Storm Dolphin was located near latitude 32.0 degrees north and longitude 138.6 degrees east. That is about 205 nautical miles south-southwest of Yokosuka, Japan. Dolphin was moving to the northeast and had maximum sustained winds of 50 knots (58 mph/92 kph).

Dolphin is forecast to move northeast and will gradually weaken before becoming extra-tropical near Tokyo.

NASA Researches Tropical Cyclones

Hurricanes/tropical cyclones are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

NASA's Terra satellite is one in a fleet of NASA satellites that provide data for hurricane research.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America's leadership in space and scientific exploration.

For forecast updates on hurricanes, visit: http://www.hurricanes.gov

By Rob Gutro
NASA's Goddard Space Flight Center

According to the World Health Organization, more than a billion people, that is, about 15% of the world's population, have various forms of disability. Every year, up to half a million people receive spinal cord injuries, which are often accompanied by paralysis, and disorders of autonomic functions. To find ways to restore health to people with disabilities, researchers are developing invasive neuroprostheses that can transmit electrical signals to the spinal cord and brain and recover lost functions.

One of the main challenges faced by doctors and scientists is the adjustment of neuroprostheses to the surrounding nerve tissues of a person. Despite the biocompatible elastic materials, it is not always possible to adapt quickly the device to the anatomical and age characteristics of the patient. The solution to this problem has been proposed by a research team headed by Professor Pavel Musienko from the Institute of Translational Biomedicine at St Petersburg University and Professor Ivan Minev from the University of Sheffield (the Department of Automatic Control and Systems Engineering, the University of Sheffield). They have developed a new 3D printing technology that makes it possible to rapidly customise muscular and neural implants for monitoring and restoring of motor and autonomic functions.

This patient-specific approach is now possible thanks to NeuroPrint hybrid 3D printing technology. First, the printer creates the geometry of the future implant made of silicone, which also serves as an insulating material. Then microparticles of platinum or another electrically conductive element of the implant are applied to the framework. Then the surface is activated by cold plasma. Moreover, the number and configuration of electrodes in the neural implant can be changed, producing devices for implantation in the tissue of the spinal cord, brain or muscles. The average production time from project creation to prototyping can be just 24 hours.

'By the developed technology, the process of creating implants can become a lot faster and cheaper,' said Professor Pavel Musienko, Head of the Laboratory of Neuroprosthetics at the Institute of Translational Biomedicine, St Petersburg University. 'Considering the compactness of the equipment and the versatility of the approach, it is quite likely that in the future it will be possible to produce patient-specific neural implants right in the hospital. This follows the principles of personalized medicine and will minimise the cost and delivery time as much as possible.'

Neuroscientists have already exploited the NeuroPrint technology to carry out research on various model objects - mammals and zebrafish. It has shown that the new neural implants have a high level of biointegration and functional stability. Also, they are as good as their counterparts when they are used to restore motor functions of the limbs and monitor the bladder activity. Additionally, the scientists have been able to print soft implants similar in shape and mechanical characteristics to the dura mater - outer connective tissue membrane of the brain. This is an important achievement, since many scientific experiments cannot be carried out due to too rigid neuronal implants that are not suitable for the soft structures of the nervous tissue. Moreover, this limits their use in clinical practice.

'We have tested our development in experiments on freely moving rats for chronic recording of the electrocortical signals of the cerebral cortex, that is a necessary element of the brain-computer interface,' said Pavel Musienko. 'The experiments on paralysed animals have shown that electrical stimulation of neural networks effectively restores locomotor function. Thus, the NeuroPrint technology opens up new opportunities both for basic research into the central nervous system and for neuroprosthetics when people suffer from various diseases and injuries.'

Recent work published by researchers at the University of Kentucky's Sanders-Brown Center on Aging (SBCoA) highlights what the lead investigator calls the "cornerstone" of her lab. Maj-Linda Selenica, assistant professor at SBCoA, led the study recently published in BBA Molecular Basis of Disease. She says their approach was unconventional as it looked at the molecular mechanisms implicated in TDP-43 biology, which is the focus of her lab.

TDP-43 is a DNA/RNA binding protein that has been found to be the hallmark pathology in a wide range of neurodegenerative diseases. Selenica says their study is the first to provide a novel pathway and identify potential therapeutic targets for TDP-43 proteinopathies - especially in Alzheimer's disease and the newly characterized form of dementia known as LATE.

The new pathway discovered by Selenica and her team is known as Eukaryotic Translation Initiation Factor 5A (eIF5A). "Our study showed that eIF5A hypusination (a modification of the protein) governs TDP-43 accumulation and aggregation in the cytoplasm, as well as accumulation of TDP-43 in membranless organelles in the cytoplasm which are called stress granules. More importantly, pharmacological inhibition of an enzyme generating hypusinated eIF5A significantly reduced TDP-43 cytoplasmic accumulation and aggregation in the cells."

Selenica says there are many important takeaways from this particular study including that this work has just scratched the surface of understanding the mechanism of hypusinated eIF5A in TDP-43 pathology. "Our understanding of TDP-43 function has advanced profoundly in the past several years; however, its complete role and the molecular mechanisms that lead to disease are not fully understood."

A lot of recent work regarding TDP-43 has been the result of the work of some of Selenica's colleagues at SBCoA, making this study important not only for Selenica's lab in particular but for the combined effort at SBCoA to find a cure. Dr. Pete Nelson, senior pathologist at SBCoA, and his team recently identified TDP-43 as the defining feature of LATE (limbic predominant age-related TDP-43 encephalopathy), which mimics the clinical presentation of Alzheimer's disease but has its own distinct pathology. Additionally, Erin Abner Ph.D., an associate professor at UK's SBCoA and College of Public Health investigated the impact of co-morbid quadruple misfolded proteins (Aβ, tau, α-synuclein, and TDP-43). That study revealed that the prevalence of TDP-43 proteinopathy with AD pathology (tau and Aβ), correlated with increased early cognitive decline and severity of AD progression.

Altogether these pivotal findings signify the importance of TDP-43 in dementia, and especially Alzheimer's disease and LATE. "Identifying new pathways implicated in TDP-43 pathology are extremely attractive as there are very limited therapeutic strategies for TDP-43 pathology - and there is no cure," said Selenica.

Her lab has now moved into investigating their newly discovered pathway in animal models. Ultimately, they are aiming to develop therapeutic strategies and the utilization of hypusinated eIF5A as a fluid biomarker.

Slow-moving post-tropical storm Beta continues to drop large amounts of rainfall in Texas as it moves into the Lower Mississippi Valley on Sept. 23. A NASA satellite rainfall product that incorporates data from satellites and observations estimated Beta's rainfall rates.

Flash Flood Watches in Effect on Sept. 23

NOAA's National Weather Service issued warnings and watches for Beta on Sept. 23. There are Flash Flood Watches currently in effect across southeast Texas and southern Louisiana.

What is a Post-tropical Cyclone?

NHC defines a post-tropical cyclone as a former tropical cyclone. This generic term describes a cyclone that no longer possesses sufficient tropical characteristics to be considered a tropical cyclone. Post-tropical cyclones can continue carrying heavy rains and high winds. Former tropical cyclones that have become fully extratropical as well as remnant lows are both classes of post-tropical cyclones.

Beta's Status on Sept. 23

At 5 a.m. EDT (0900 UTC), the center of Post-Tropical Cyclone Beta was located near latitude 29.5 degrees north and longitude 95.0 degrees west. That is about 30 miles (45 km) east-southeast of Houston, Texas and about 70 miles (115 km) west-southwest of Port Arthur, Texas.

The post-tropical cyclone is moving toward the east-northeast near 9 mph (15 kph) and this motion is expected to shift more toward the northeast during the next 48 hours.

Maximum sustained winds are near 30 mph (45 kph) with higher gusts. Slow weakening is forecast during the next 48 hours. The estimated minimum central pressure is 1007 millibars.

Estimating Beta's Rainfall Rates from Space

NASA's Integrated Multi-satellitE Retrievals for GPM or IMERG, which is a NASA satellite rainfall product, estimated on Sept. 23 at 3:30 a.m. EDT (0730 UTC) that Beta was generating between 1 and 5 mm (0.04 and 0.2 inches) of rain per hour. IMERG also found that rainfall was occurring around the center of circulation in east Texas and in areas extending northeast into Louisiana and out over the Gulf of Mexico. Rainfall throughout most of the storm was estimated as falling at a rate between 0.3 and 1 mm (0.01 to 0.04 inches) per hour.

At the U.S. Naval Laboratory in Washington, D.C., the IMERG rainfall data was overlaid on infrared imagery from NOAA's GOES-16 satellite to provide a full extent of the storm.

NHC Key Messages

NOAA's National Weather Service Weather Prediction Center in College Park, Md. issued two key messages about Beta on Sept. 23:

RAINFALL: For the upper Texas coast, additional rainfall of 3 to 5 inches with isolated storm totals up to 15 inches is expected through Wednesday afternoon. Significant urban flooding will continue as well as minor to isolated moderate river flooding. Flash flooding will remain possible through Wednesday afternoon. Rainfall totals of 2 to 5 inches are expected east into the Lower Mississippi Valley, portions of the Tennessee Valley, and the southern Appalachians through the end of the week. Flash and urban flooding is possible, as well as isolated minor river flooding on smaller rivers.
SURF: Swells generated by a combination of Beta and a stationary front over the northern Gulf of Mexico will continue from the Upper Coast of Texas to the Western Florida Panhandle during the next couple of days.  These swells are likely to cause life-threatening surf and rip current conditions.

Beta is forecast to continue moving in an easterly direction into the Lower Mississippi Valley, portions of the Tennessee Valley, and the southern Appalachians through the end of the week.

What Does IMERG Do?

This near-real time rainfall estimate comes from the NASA's IMERG, which combines observations from a fleet of satellites, in near-real time, to provide near-global estimates of precipitation every 30 minutes. By combining NASA precipitation estimates with other data sources, we can gain a greater understanding of major storms that affect our planet.

What the IMERG does is "morph" high-quality satellite observations along the direction of the steering winds to deliver information about rain at times and places where such satellite overflights did not occur. Information morphing is particularly important over the majority of the world's surface that lacks ground-radar coverage. Basically, IMERG fills in the blanks between weather observation stations.

NASA Researches Tropical Cyclones

Hurricanes/tropical cyclones are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America's leadership in space and scientific exploration.

For more information about NASA's IMERG, visit: https://pmm.nasa.gov/gpm/imerg-global-image

For forecast updates on hurricanes, visit: http://www.hurricanes.gov

By Rob Gutro
NASA's Goddard Space Flight Center

NASA's Terra satellite passed over post-tropical storm Paulette after it had transitioned for a second time. Using infrared imagery, Terra found no strong storms remained.

Paulette has had quite a history. Paulette formed in the Central Atlantic Ocean on Sept. 6 as Tropical Depression Seventeen and became a tropical storm the next day. Paulette became a hurricane on Sept. 12. As a hurricane, Paulette's eye passed directly over Bermuda, then weakened and became a post-tropical cyclone on Sept. 16 in the North Atlantic Ocean when it was located 450 miles (725 km) east-southeast of Cape Race Newfoundland, Canada. A Post-Tropical Storm is a generic term for a former tropical cyclone that no longer possesses sufficient tropical characteristics to be considered a tropical cyclone. Then on Sept. 22, the remnants of Paulette organized and re-formed into a tropical storm. Only to devolve again to a post-tropical storm later that day.

At 11 p.m. EDT on Sept. 22 (0300 UTC on Sept. 23), Dan Brown, Warning Coordination Meteorologist, Senior Hurricane Specialist at NOAA's National Hurricane Center in Miami, Fla. noted, "Paulette had been devoid of deep convection since early Tuesday and the shallow convection mentioned in the previous advisory has also waned. Therefore, Paulette has again become a post-tropical cyclone."

NASA's Terra Satellite Examines Paulette

NASA's Terra satellite uses infrared light to analyze the strength of storms by providing temperature information about the system's clouds. The strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On Sept. 23 at 8:45 a.m. EDT (1245 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Terra satellite gathered infrared data on Paulette. There were no strong storms on the infrared MODIS imagery. The imagery found only one small area of convection where cloud top temperatures are as cold as minus 50 degrees Fahrenheit (minus 45.5 Celsius).

Final Status of Paulette

The last public advisory issued by the National Hurricane Center on Paulette was posted on Sept. 22 at 11 p.m. EDT (0300 UTC). At that time, the center of Post-Tropical Cyclone Paulette was located near latitude 34.8 degrees north and longitude 20.0 degrees west. That is about 445 miles (720 km) east-southeast of the Azores Islands.  The Azores Islands are a Portuguese archipelago in the North Atlantic Ocean. They are located about 930 miles (1,500 km) from Lisbon, Portugal.

Maximum sustained winds are near 40 mph (65 kph) with higher gusts. Slow weakening is forecast. The post-tropical cyclone was moving toward the east near 12 mph (19 kph). An eastward to east-northeastward motion is forecast through midday Wednesday. A decrease in the forward motion along with turns to the southeast then south are expected late Wednesday through Thursday. A west-southwestward motion is forecast to begin by late this week.

Paulette's Final Forecast  

Post-tropical cyclone Paulette is expected to become a remnant low later today, Sept. 23.