Tech

On an expedition to the Central Andean Plateau, researchers from the Smithsonian Tropical Research Institute (STRI) and colleagues were astounded to find a huge fossil-tree buried in the cold, grassy plain. The plant fossil record from this high-altitude site in southern Peru contains dramatic reminders that the environment in the Andes mountains changed drastically during the past 10 million years, but not in the ways that climate models of the past suggest. Findings from the expedition are presented in the journal Science Advances.

"This tree and the hundreds of fossil wood, leaf and pollen samples we collected on the expedition, reveal that when these plants were alive the ecosystem was more humid--even more humid than climate models of the past predicted," said Camila Martinez, a fellow at STRI, who recently finished her doctorate at Cornell University. "There is probably no comparable modern ecosystem, because temperatures were higher when these fossils were deposited 10 million years ago."

The anatomy of the petrified (permineralized) wood the researchers found is very much like wood anatomy in low-elevation tropical forests today. Indeed, the altitude then was probably only 2,000 meters above sea level.

But that ecosystem did not last for long. Today, the arid, intermountain plateau lies at 4,000 meters above sea level.

Five million year-old fossils from the same sites confirmed that the Puna ecosystem that now dominates the Andes' high mountain plateaus had been born: the younger pollen samples were mostly from grasses and herbs, rather than from trees. Leaf material was from ferns, herbs and shrubs, indicating that the plateau had already risen to its current altitude.

"The fossil record in the region tells us two things: both the altitude and the vegetation changed dramatically over a relatively short period of time, supporting a hypothesis that suggests the tectonic uplift of this region occurred in rapid pulses," said Carlos Jaramillo, STRI staff scientist and project leader.

"Andean uplift played an important role in shaping the climate of South America, but the relationship between the rise of the Andes, local climates and vegetation is still not well understood," Martinez said. "By the end of this century, changes in temperature and atmospheric carbon dioxide concentrations will again approximate the conditions 10 million years ago. Understanding the discrepancies between climate models and data based on the fossil record help us to elucidate the driving forces controlling the current climate of the Altiplano, and, ultimately, the climate across the South American continent.

Understanding the skin damage caused by rubbing could lead to better topical skin treatments and help prevent the formation of new routes for viral and bacterial infection.

Tohoku University biomechanical engineers have developed a better understanding of the damage that can be caused by something rubbing against the skin. The study was published in the International Journal of Pharmaceutics. Kenji Kikuchi, who was involved in the study, says their findings suggest that damaged skin from rubbing face masks and coverings could potentially provide a route for transdermal virus infection, however further research would be needed to investigate how much rubbing is cause for concern.

The uppermost part of the skin, called the stratum corneum, is formed of layers of keratinocyte cells suspended in a lipid matrix. The stratum corneum plays an important protective role, forming a barrier against the invasion of viruses and bacteria, maintaining skin hydration, and managing skin recovery following damage.

Kikuchi and colleagues at Tohoku University in Japan wanted to develop a more in depth understanding of the mechanics of skin damage caused by rubbing. This could help scientists develop more effective drugs that are applied through the skin and to understand how to better prevent viruses and bacteria from gaining access to the body through damaged skin.

The researchers measured the mechanical effects of rubbing on pig skin, which is very similar to human skin. A gear rotated against skin samples at known rates and pressures. The scientists then measured the damage this caused by exposing the skin samples to a fluorescent dye. The more damaged the skin, the more the fluorescent dye was able to permeate it.

The team found that the mechanical rubbing caused keratinocytes to shrink and wrinkle in the direction of the rubbing. Gaps also formed between the keratinocytes, degrading the skin's barrier function. They then developed a mathematical formula to describe the permeability of rubbed skin, which can be estimated from the amount of strain applied.

"We believe our findings could improve transdermal drug delivery and we plan to investigate the development of novel topical drugs that can be applied to the skin by rubbing," says Kikuchi.

He adds that their findings could apply to the current pandemic if rubbing face masks were found by further research to cause skin damage, potentially allowing another avenue for COVID-19 infection. The team did not specifically investigate this topic and Kikuchi encourages people to continue to wear face cover-ings that fit comfortably over the nose and mouth.

Sunflower oil, which is found in almost every home, can be used not only in cooking, everyday life and cosmetology - it will help avoid complications (gas hydrates and corrosion) during oil and gas production. Scientists of the priority area of Kazan University intend to apply inhibitors developed on its basis in harsh Arctic conditions. Unique reagents have shown high efficiency during laboratory tests. They can prevent freezing in wells when producing hydrocarbon resources in the Arctic. Our employees partnered up with colleagues from Russian Oil and Gas University, Shahid Beheshti University (Iran) and University of Isfahan (Iran).

Today the world knows several ways of dealing with "gas hydrate plugs." The most common and simplest one is to cut them out. But this method has many drawbacks, is extremely ineffective, unsafe and, moreover, has long been outdated. This technology has been replaced by inhibitors. However, all of the currently existing inhibitors have different side effects: some are environmentally unsafe, others are too expensive. Therefore, the researchers opted for a budget-friendly, affordable and biodegradable product, adding it to the "recipe" for creating an inhibitor that is truly unique in its properties.

"We found that sunflower oil can be modified in several ways, and many molecules can be synthesized from it. The presence of alkyl chains in its structure can improve hydrate inhibition. Sunflower oil-based molecules can easily degrade due to the presence of ester groups in their structure," explains Research Associate Abdolreza Farhadian.

Obviously, when it comes to working in offshore fields, it is impossible to ignore environmental issues, bearing in mind that the components should not be toxic. Therefore, the task of scientists was not only to ensure the effectiveness of the inhibitor, but also to ensure environmental safety for the aquatic environment and its inhabitants.

"When we were developing this reagent, we were looking for a basis for the synthesis of molecules that would be the least toxic, biodegradable, and paid attention to natural compounds, primarily natural oils. From the point of view of chemistry, it was sunflower oil that interested us. First, it allows, by its structure, to implement exactly the synthesis method that we have invented. Secondly, sunflower oil is just a natural product, non-toxic and biodegradable. Exactly what we need," says Head of Hydrocarbon Research at KFU Mikhail Varfolomeev.

"It should be noted that the new sunflower oil-based inhibitor also allows the simultaneous killing of two birds with one stone - gas hydrates and pipeline corrosion. In the presence of such complications in oil and gas production, the proposed multifunctional inhibitors can be more effective than reagent mixtures used in industry," adds co-author, Senior Research Associate Andrey Stoporev.

By the way, this development is not the first green technology invention. In 2019, this research team synthesized castor oil-based inhibitors that are equally effective in eliminating gas hydrates and corrosion.

The current situation shows that a fairly affordable and inexpensive tool can act as a solution to a large-scale problem, and the technique itself can be easily implemented in modern industry.

COLUMBUS, Ohio - Feelings of panic when a person is away from their smartphone could be connected to general feelings of inadequacy and inferiority, a new study of young people in Portugal suggests.

The study, published in the most recent issue of the journal Computers in Human Behavior Reports, found that gender has no bearing on whether people will feel apprehensive or anxious without their phones. But people who feel that way tend to be more anxious and obsessive-compulsive in their day-to-day lives than other people, the study suggests.

"It is that fear, that panicky feeling, of 'oh, no, I left my phone at home,'" said Ana-Paula Correia, one of the authors of the study, associate professor in the department of educational studies at The Ohio State University and director of Ohio State's Center on Education and Training for Employment.

This study was based on Correia's previous work, which created a questionnaire to evaluate individuals' reliance on their smartphones and explored the term "nomophobia" -- the fear of being away from one's smartphone. (Nomophobia is not recognized as a diagnosis by the American Psychiatric Association.)

For this study, researchers gave that questionnaire and another that evaluated psychopathological symptoms such as anxiety, obsession-compulsion and feelings of inadequacy to 495 adults aged 18 to 24 in Portugal. Those adults reported using their phones for between four and seven hours a day, primarily for social networking applications.

The researchers found that the more participants used their smartphone each day, the more stress they reported feeling without their phone. A little more than half of the study participants were female; the study didn't find a link between gender and feelings of nomophobia.

The researchers also found that the higher participants scored on obsession-compulsion, the more they feared being without their phone. Obsession-compulsion was measured by asking participants to rate how much they felt they had to "check and double-check what you do" and similar questions.

There is a difference between normal smartphone use that benefits a person's life - say, video chatting with friends when you can't be together in person or using it for work - and smartphone use that interferes with a person's life. That kind of behavior, Correia said, is more likely to cause anxiety when we are away from our phones.

And, the study's results suggest that people experiencing tension might see their phones as a stress-management tool.

"This concept is about more than just the phone," Correia said. "People use it for other tasks, including social media, connecting, knowing what's going on with their social media influencers. So being away from the phone or the phone having a low battery can sort of sever that connection and leave some people with feelings of agitation."

The data of 61,751 pregnant women, out of approximately 100,000 collected by the Japan Environment and Children's Study analyzed the association between the maternal usage of insecticides and insect repellents during pregnancy and neonatal hyperbilirubinemia. The Koshin Unit Center at Shinshu University played a central role in this analysis. Newborns appear jaundiced, or appear to have yellow skin and sclera of the eyes when bilirubin in the blood becomes too high. When bilirubin builds up in the brain and is left untreated, neurotoxic damage can occur in newborns. Phototherapy is most often used to treat neonatal hyperbilirubinemia.

This study found that frequent use of insecticide spray indoors resulted in 1.21 times higher incidence of neonatal hyperbilirubinemia requiring phototherapy. On the other hand, when a spray or lotion-type insect repellent was used frequently, the incidence was 0.70 times lower. No correlation was observed between neonatal hyperbilirubinemia requiring treatment regarding the use of insect repellents for clothing, mosquito coils, electric mosquito repellents, pesticides and pesticides for gardening. Exposure of insecticides and insect repellent at the end of pregnancy was not evaluated in this study nor was data collected for blood concentration of insecticides and insect repellents. In addition, the effect of slightly different phototherapy implementation standards for neonatal hyperbilirubinemia among medical institutions has not been examined. It is necessary to consider these issues in the future.

The results of this study was published in Pediatric Research on August 5, 2020.

*The content of this research is the opinion of the author, not the views of the Ministry of the Environment and the National Institute for Environmental Studies.

1. What is The Japan Environment and Children's Study?

The Japan Environment and Children's Study (JECS) has been conducted since 2010 to clarify the effects of exposure to chemical substances on the health of children during the fetal and childhood stages. This is a large-scale, long-term birth cohort survey of 100,000 sets of parents and children nationwide. In addition to collecting, storing and analyzing biological samples such as maternal blood, umbilical cord blood, and breast milk, the study will follow up on the participating children until they are 13 years old to clarify the environmental factors that affect their health.

JECS includes a period of five years for data analysis and is scheduled to be completed in the year 2032. The National Institute for Environmental Studies is the core center of research, the National Center for Child Health and Development functions as a medical support center, and 15 universities were selected for unit centers to work as regional survey bases.

2. Research background

High levels of serum bilirubin cause jaundice. Jaundice is one of the most common medical symptoms during the neonatal period. About 60% of children have overt jaundice. The frequency of jaundice in the neonatal period varies by race, and Asians are twice as likely as Caucasians and three times more likely than blacks to exhibit jaundice. Hyperbilirubinemia is a risk factor for nuclear jaundice (kernicterus) and cerebral palsy, and Asians are considered to have a higher risk of nuclear jaundice than other races.

Agricultural chemicals, insecticides and insect repellents are used widely, all over the world. They include organic phosphorus, pyrethroids, carbamates, neonicotinoids and DEET. It is said that these substances can induce oxidative stress by reducing the activity of SOD (superoxide dismutase), catalase, glutathione reductase, which are enzymes that have antioxidative effects in the body. Excessive oxidative stress causes hemolysis from red blood cell lipid peroxidation. A risk factor for hyperbilirubinemia may be exposure to insecticides during pregnancy if it causes hemolysis of the red blood cells of the baby.

Therefore, this study investigated the effect of the frequency of use of insecticides and insect repellents during pregnancy in mothers on the development of neonatal hyperbilirubinemia that required phototherapy.

3. Research content and results

This study used the data of approximately 100,000 pregnant women fixed in April of 2016. Of these, data of 61,751 women was eventually analyzed, which excluded data of stillbirths, miscarriages, infants with a birth weight less than 2500g, and those missing data in factors that are considered relevant. Information also included maternal use of insect repellents for clothes during pregnancy, indoor spray insecticides, mosquito coil, electric mosquito repellents, pesticides and insecticides for gardening, spray or lotion type insect repellents.

Of these, 5,985 (9.7%) received phototherapy for neonatal hyperbilirubinemia. Answers to the self-administered questionnaires conducted during the second and third trimesters of pregnancy was used as an indicator for the frequency of maternal exposure to insecticides and insect repellents. 36,610 (59.2%) mothers used insect repellents for clothes during pregnancy, 20,352 (33.0%) used indoor spray insecticides, and 19,518 (31.6%) used mosquito coils and electric mosquito traps. 5,333 (8.6%) used herbicides and pesticides for gardening, and 15,309 (24.8%) used spray or lotion type insect repellent.

Potential confounding factors associated with neonatal hyperbilirubinemia include the age of the expectant woman, gender of the baby, gestational age, birth weight, presence of birth asphyxia, maternal complications during pregnancy, obstetric complications, household income, and the mother's education history. Logistic regression analysis was used considering these confounding factors, and the study examined the relationship between the frequency of use of insecticides or insect repellents during pregnancy and the incidence of neonatal hyperbilirubinemia that required phototherapy.

As a result, it was found that mothers who used spray insecticides indoors more than several times a week during pregnancy gave birth to babies with neonatal hyperbilirubinemia, which requires phototherapy at a rate 1.21 times higher than in a group of mothers who never used insecticide or repellents during pregnancy. Regarding the use of other insect repellants, a high frequency of use was not clearly associated with the occurrence of neonatal hyperbilirubinemia requiring phototherapy. On the other hand, the use of spray or lotion type insect repellent, neonatal hyperbilirubinemia requiring phototherapy is less likely to occur in the group where the frequency of use is more than several times a week compared to the group which is not used at all. The result is as low as 0.70 times. A similar tendency was observed when low birth weight infants with a birth weight of less than 2,500 g were also analyzed.

4. Future implications

This is the first study to examine the association between the incidence of neonatal hyperbilirubinemia requiring treatment and maternal exposure to insecticides and insect repellents during pregnancy.

The results of this study indicate that neonatal hyperbilirubinemia, which requires phototherapy, is more likely to occur in infants born to mothers who use spray insecticide indoors more often than several times a week during pregnancy compared to those who did not. The result was 1.21 times more likely to develop neonatal hyperbilirubinemia. On the other hand, a mechanism that may explain the reason why the frequent use of spray or lotion type insect repellents resulted in a lower probability of developing neonatal hyperbilirubinemia requiring phototherapy is unknown.

In this study, no information on exposure of mothers to insecticides or insect repellant was obtained as objective data such as blood concentration. In addition, the survey period is in the middle and late trimesters. It has not been possible to accurately evaluate the exposure during the last trimester of pregnancy immediately before delivery, which is thought to have the most effect on hyperbilirubinemia in newborns. In addition, the level of serum bilirubin used as the phototherapy criteria at each medical institution may be different, and these issues need to be considered.

JECS investigates not only chemical substances but also environmental factors, genetic factors, social factors, lifestyle factors. It is expected that more information will be available on the relationship between these factors and neonatal hyperbilirubinemia. Therefore, it is necessary to examine the relationship between exposure to insecticides and insect repellents and the occurrence of neonatal hyperbilirubinemia by comprehensively considering the knowledge of the relationship with factors other than these chemical substances. It is hoped that environmental factors such as chemical substances that affect the growth and health of children will continue to be clarified.

A simple coffee and a quick catnap could be the cure for staying alert on the nightshift as new research from the University of South Australia shows that this unlikely combination can improve attention and reduce sleep inertia.

In Australia, more than 1.4 million people are employed in shift work, with more than 200,000 regularly working night or evening shifts.

Lead researcher, Dr Stephanie Centofanti from UniSA Online and the Sleep and Chronobiology Laboratory at UniSA says the finding could help counteract the kind of sleep inertia that is experienced by many shiftworkers.

“Shift workers are often chronically sleep-deprived because they have disrupted and irregular sleep patterns,” Dr Centofanti says.

“As a result, they commonly use a range of strategies to try to boost their alertness while on the nightshift, and these can include taking power naps and drinking coffee – yet it’s important to understand that there are disadvantages for both.

“Many workers nap during a night shift because they get so tired. But the downside is that they can experience ‘sleep inertia’ – that grogginess you have just after you wake up – and this can impair their performance and mood for up to an hour after their nap.

“Caffeine is also used by many people to stay awake and alert. But again, if you have too much coffee it can harm your overall sleep and health. And, if you use it to perk you up after a nap, it can take a good 20-30 minutes to kick in, so there’s a significant time delay before you feel the desired effect.

“A ‘caffeine-nap’ (or ‘caff-nap’) could be a viable alternative – by drinking a coffee before taking a nap, shiftworkers can gain the benefits of a 20-30-minute nap then the perk of the caffeine when they wake. It’s a win-win.”

The small pilot study tested the impact of 200 mg of caffeine (equivalent to 1-2 regular cups of coffee) consumed by participants just before a 3.30am 30-minute nap, comparing results with a group that took a placebo.

Participants taking a ‘caffeine-nap’ showed marked improvements in both performance and alertness, indicating the potential of a ‘caffeine-nap’ to counteract sleep grogginess.

Dr Centofanti says this shows a promising fatigue countermeasure for shift workers. She says the next move is to test the new finding on more people.

New biomaterials developed at the University of Bayreuth eliminate risk of infection and facilitate healing processes. A research team led by Prof. Dr. Thomas Scheibel has succeeded in combining these material properties which are highly relevant to biomedicine. These nanostructured materials are based on spider silk proteins. They prevent colonization by bacteria and fungi, but at the same time proactively assist in the regeneration of human tissue. They are therefore ideal for implants, wound dressings, prostheses, contact lenses, and other everyday aids. The scientists have presented their innovation in the journal Materials Today.

It is a widely underestimated risk of infection: Microbes settling on the surfaces of objects indispensable in medical therapy or for quality of life generally. Gradually, they form a dense, often invisible biofilm that cannot be easily removed, even by cleaning agents, and which often is resistant against antibiotics and antimycotics. Bacteria and fungi can then migrate into the adjacent tissue of the organism. As a result, they not only interfere with various processes of healing, but can even cause life-threatening infections.

With a novel research approach, University of Bayreuth scientists have now found a solution to this problem. Using biotechnologically produced spider silk proteins, they have developed a material that prevents the adhesion of pathogenic microbes. Even streptococci, resistant to multiple antibacterial agents (MRSA), have no chance of settling on the material surface. Biofilms growing on medical instruments, sports equipment, contact lenses, prostheses, and other everyday objects may therefore soon be history.

Moreover, the materials are designed to simultaneously aid the adhesion and proliferation of human cells on their surface. If they can be used for e.g. wound dressings, skin replacement, or implants, they proactively support the regeneration of damaged or lost tissue. In contrast to other materials that have previously been used to regenerate tissue, the risk of infection is intrinsically eliminated. Microbial-resistant coatings for a variety of biomedical and technical applications are thus set to become available in the near future.

The Bayreuth researchers have so far successfully tested the microbe-repellent function on two types of spider silk materials: on films and coatings that are only a few nanometres thick and on three-dimensional hydrogel scaffolds which can serve as precursors for tissue regeneration. "Our investigations to date have led to a finding that is absolutely ground-breaking for future research work. In particular, the microbe-repellent properties of the biomaterials we have developed are not based on toxic, i.e. not cell-destroying, effects. The decisive factor rather lies in structures at the nanometre level, which make the spider silk surfaces microbe-repellent. They make it impossible for pathogens to attach themselves to these surfaces", explains Prof. Dr. Thomas Scheibel, who is the Chair of Biomaterials at the University of Bayreuth.

"Another fascinating aspect is that nature has once again proven to be the ideal role model for highly advanced material concepts. Natural spider silk is highly resistant to microbial infestation and the reproduction of these properties in a biotechnological way is a break-through", adds Prof. Dr.-Ing. Gregor Lang, one of the two first authors and head of the research group of Biopolymer Processing at the University of Bayreuth.

In the Bayreuth laboratories, spider silk proteins were specifically designed with various nanostructures in order to optimize biomedically relevant properties for specific applications. Once again, the networked research facilities on the Bayreuth campus have proven their worth. Together with the Bavarian Polymer Institute (BPI), three other interdisciplinary research institutes of the University of Bayreuth were involved in this research breakthrough: the Bayreuth Centre for Material Science & Engineering (BayMAT), the Bayreuth Centre for Colloids & Interfaces (BZKG), and the Bayreuth Centre for Molecular Biosciences (BZKG).

The ten km long, bright white coast of Germany's largest island, Rügen, is shaped by episodically occurring failures. These failures were typically assumed to happen due to strong rain storms. In a study carried out over more than two years, scientists of GFZ German Research Centre for Geosciences were able to draw a new and surprisingly detailed picture of coastal cliff failure activity. The study is based on continuous seismic measurements and high resolution aerial images, and has been published in the Journal of Geophysical Research.

The chalk cliff coast of Rügen, with the 118 m high Königsstuhl rock column, is a renowned landmark of the National Park Jasmund. The cliff is formed by fossil calcareous algae and retreats by up several decimeters per year on average. That retreat is spectacularly accomplished by the break-off of large chalk chunks (in this study up to 5000 m³) that cause strong impacts on the beach. These impacts generate small earthquakes that were sensed by the scientists using seismometers; a network of such sensors was installed along the coast between spring 2017 and 2019. Along with meteorological data and drone-based 3D models of the cliff, the seismic data enabled the routine collection of essential data about failures that were previously available only in rare cases: timing, duration and evolution of single events with sub-second resolution, position and volume of detachment and deposit zones, and properties of the ground around the occurrence of an event.

Based on more than 80 detected failures, the scientists were able to identify several interconnected drivers. "Sufficient wetting of the chalk by water is the primary reason", says Michael Dietze, lead author of the study. "However, the water is not only provided by rain onto the cliff surface, but also by ground water flow and condensation of air moisture during the colder night time hours. Consequently, the cliff is preferentially active at night, as well as a few hours and also a day after rain events." Failures predominantly happen in winter, because during that season the trees are not able to withdraw soil water, causing wetter ground conditions. The study found a dramatic effect of wetter and drier than average summers. In 2017, when 126 % of the typical rain amount was measured, a total of 65 failures happened. In contrast, the exceptional drought summer of 2018 (51 % of the average rain amount) resulted in only 11 cliff failure events during the following winter.

The long term effects of such dry summers for the cliff remain a matter of debate. Generally, it is the small failures that provide the beach with enough loose material to prevent the waves from cutting into the basal parts of the cliff. If that sediment is lacking, wave driven undermining at the base will prepare the cliff for large scale sector collapse. The scientists have now instrumented the neighboring island of Hiddensee, to investigate the direct effect of waves in more detail. In addition, the northern part of this island is periodically struck by massive slope failures, most recently in winter 2019, when a block of several hundred meter length moved downslope by more than 20 cm.

Ithaca, N.Y.--Ecosystems can be incredibly complex, with many interacting species. In many habitats, predators shape they behavior of prey and prey shape the behavior of predators. This paper provides a detailed look at the predator-prey relationship between bats and katydids, a group of insects related to crickets and grasshoppers.

Some species of bats hunt katydids by eavesdropping on their mating calls. However, katydids aren't defenseless. Many species of katydids have ears that can hear the ultrasonic echolocation calls of bats. In some habitats, katydids stop calling when they hear the echolocation calls of bats. We studied katydids in Neotropical forests and predicted that they would stop calling when they heard the echolocation calls of approaching bats. What we found was a surprise - most of the katydid species continued calling even when hearing the echolocation calls of predatory eavesdropping bats.

In Neotropical forests, there are many species of bats. Some of these bats eat fruit and others catch flying insects. Most of these bat species are no risk to a perched, singing katydid. However, all of these bats produce echolocation, so while the forest is full of echolocation calls, less than 4% of those calls come from bats that might eavesdrop on katydid calls. For a katydid, this means that calling is very risky, but because there are so many bats producing echolocation calls, if katydids stop singing when they hear echolocation, they would have few opportunities to attract a mate.

By measuring the neural activity from their ears, we know that katydids are capable of hearing bats, but most of the species that we studied sing at the same rate, regardless of whether they are hearing bats. Most of the species that we studied have a more proactive strategy, using very short, very rare calls. Many species produce very little sound...less than two seconds per insect per night!

This is a cool example of how the evolution of predator-prey relationships is affected by other species in the environment, underscoring the complex and interconnected dynamics of natural ecosystems.

Researchers at The University of Texas at Dallas say drone technology has the potential to be a genuine game changer in the retail industry, with its promise to enable retailers to offer unheard-of delivery lead times and near-perfect delivery-time customization adaptability.

In a new study, recently published online in Production and Operations Management, three faculty members from the Naveen Jindal School of Management explored how drone delivery could change retail logistics networks. The paper focuses on the use of customer-facing delivery centers, also known as last-mile warehouses.

Dr. Milind Dawande, professor of operations management and one of the paper's co-authors, said last-mile retail delivery via drones is being viewed as a truly disruptive technology. Retailers worldwide are pursuing approaches to enable faster delivery, and drones arguably represent the most encouraging technological innovation toward this goal, he said.

The study found that both the number of last-mile warehouses and the delivery speed of the drones will increase as technology matures. In other words, last-mile delivery networks will become more decentralized, with drones operating at increasingly faster speeds.

The analysis also showed that while perfect customization of delivery-time guarantees is more profitable, retailers can capture a sizeable portion of the profit by partitioning their market into a few zones and offering the best-possible delivery-time guarantee for each zone.

"If a retailer promises each customer a different delivery time based on the customer's location, that would be perfect customization," Dawande said. "For example, a retailer could give any customer who is 1 mile away a delivery-time guarantee of five minutes and a customer 1.5 miles away a delivery-time guarantee of seven minutes. While perfect customization is theoretically best for the retailer, it is impractical. Instead, the retailer might offer all customers less than 5 miles away a guaranteed delivery time of 15 minutes.

"In other words, limited customization is good enough."

Faster delivery times are more profitable because it implies more demand, Dawande said. Customers' needs are time-sensitive. For example, if a retailer promises delivery of a book in 15 minutes, the demand is likely to go up, as compared to a three-day delivery promise.

The researchers note that increasing delivery speed of drones can help improve profitability only if it is accompanied by an increase in the number of last-mile warehouses. Therefore, in congested markets, where the number of warehouses cannot be increased, the retailer may find it best to offer a delivery speed that is lower than the highest-possible speed.

Before drone technology can become widely adopted, however, privacy and safety issues need to be solved, Dawande said, as well as regulations coordinating drone travel and the public perception of fleets of drones flying overhead. The paper points to pilot programs testing the technology.

"It would be reasonable to assume that drone technology is maturing quickly, and we should see a commercial rollout on a larger scale in the not-too-distant future. The COVID-19 pandemic will perhaps hasten this process," said Dawande, who is also the Mike Redeker Distinguished Professor in Management.

Drones might be particularly appealing to customers concerned about both delivery safety and delivery speed, he said. Hands-free delivery to one's doorstep will be an advantage drones can offer in the post-COVID-19 era.

The analysis is also applicable to other dedicated delivery vehicles, such as delivery robots and electric bikes, which many retailers are testing.

The researchers noted that further research is needed into how last-mile delivery capacity might be allocated between drones and traditional approaches such as delivery trucks. On the one hand, drone delivery can enable fast delivery times and minimize the cost of human labor by using dedicated aerial vehicles that fly directly from a delivery center to the customer's location. On the other hand, delivery trucks have the capability of making multiple stops during a trip. The researchers predict that retailers will use both in order to benefit from their respective strengths.

NASA infrared imagery shows wind shear continued to batter Tropical Storm Iselle in the Eastern Pacific Ocean for the second day.

NASA's Infrared Data Finds Push of Winds

Tropical cyclones are made up of hundreds of thunderstorms, and infrared data can show where the strongest storms are located. That is because infrared data provides temperature information, and the strongest thunderstorms that reach highest into the atmosphere have the coldest cloud top temperatures.

On Aug. 28 at 2:40 a.m. EDT (0640 UTC), the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Terra satellite captured an infrared image of cloud top temperatures in Iselle. Iselle continues to produce deep convection and strong thunderstorms near the center and on its west side. The data revealed the most powerful thunderstorms minus 80 degrees Fahrenheit (minus 62.2 degrees Celsius) near the center. Wind shear was pushing the rest of the storms to the west. Some had cloud top temperatures as cold as minus 70 degrees Fahrenheit (minus 56.6. degrees Celsius) and were dropping large amounts of rain. This asymmetric cloud pattern is due to a moderate amount of easterly wind shear.

National Hurricane Center (NHC) intensity forecast follows the trend of the models, and predicts Iselle to weaken to a tropical depression in a couple of days and to a remnant low shortly thereafter.

What Wind Shear Does to a Tropical Cyclone

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.

Iselle's Status on Aug. 28, 2020

At 5 a.m. EDT (0900 UTC), the center of Tropical Storm Iselle was located near latitude 17.9 degrees north and longitude 115.0 degrees west. That is about 480 miles (770 km) southwest of the southern tip of Baja California, Mexico. Iselle is moving toward the northeast near 5 mph (7 kph) and this general motion is expected to continue through tonight. Maximum sustained winds have increased to near 60 mph (95 kph) with higher gusts. The estimated minimum central pressure is 997 millibars.

Forecast from NHC

A northward and then northwestward motion is expected during the weekend. Little change in strength is expected today, but a gradual weakening trend should begin tonight.

NASA Researches Earth from Space

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.

The inside of future nuclear fusion energy reactors will be among the harshest environments ever produced on Earth. What’s strong enough to protect the inside of a fusion reactor from plasma-produced heat fluxes akin to space shuttles reentering Earth’s atmosphere?

Zeke Unterberg and his team at the Department of Energy’s Oak Ridge National Laboratory are currently working with the leading candidate: tungsten, which has the highest melting point and lowest vapor pressure of all metals on the periodic table, as well as very high tensile strength — properties that make it well-suited to take abuse for long periods of time. They’re focused on understanding how tungsten would work inside a fusion reactor, a device that heats light atoms to temperatures hotter than the sun’s core so that they fuse and release energy. Hydrogen gas in a fusion reactor is converted into hydrogen plasma — a state of matter that consists of partially ionized gas—that is then confined in a small region by strong magnetic fields or lasers.

“You don’t want to put something in your reactor that only lasts a couple of days,” said Unterberg, a senior research scientist in ORNL’s Fusion Energy Division. “You want to have sufficient lifetime. We put tungsten in areas where we anticipate there will be very high plasma bombardment.”

In 2016, Unterberg and the team began conducting experiments in the tokamak, a fusion reactor that uses magnetic-fields to contain a ring of plasma, at the DIII-D National Fusion Facility, a DOE Office of Science user facility in San Diego. They wanted to know whether tungsten could be used to armor the tokamak’s vacuum chamber — protecting it from rapid destruction caused by the effects of plasma — without heavily contaminating the plasma itself. This contamination, if not sufficiently managed, could ultimately extinguish the fusion reaction.

“We were trying to determine what areas in the chamber would be particularly bad: where the tungsten was most likely to generate impurities that can contaminate the plasma,” Unterberg said.

To find that, the researchers used an enriched isotope of tungsten, W-182, along with the unmodified isotope, to trace the erosion, transport and redeposition of tungsten from within the divertor. Looking at the movement of tungsten within the divertor — an area within the vacuum chamber designed to divert plasma and impurities — gave them a clearer picture of how it erodes from surfaces within the tokamak and interacts with the plasma. The enriched tungsten isotope has the same physical and chemical properties as regular tungsten. The experiments at DIII-D used small metal inserts coated with the enriched isotope placed close to, but not at, the highest heat flux zone, an area in the vessel typically called the divertor far-target region. Separately, at a divertor region with the highest fluxes, the strike-point, researchers used inserts with the unmodified isotope. The remainder of the DIII-D chamber is armored with graphite.

This setup allowed the researchers to collect samples on special probes temporarily inserted in the chamber for measuring impurity flow to and from the vessel armor, which could give them a more precise idea of where the tungsten that had leaked away from the divertor into the chamber had originated.

“Using the enriched isotope gave us a unique fingerprint,” Unterberg said.

It was the first such experiment conducted in a fusion device. One goal was to determine the best materials and location for these materials for chamber armoring, while keeping impurities caused by plasma-material interactions largely contained to the divertor and not contaminating the magnet-confined core plasma used to produce fusion.

One complication with the design and operation of divertors is impurity contamination in the plasma caused by edge-localized modes, or ELMs. Some of these fast, high-energy events, akin to solar flares, can damage or destroy vessel components such as divertor plates. The frequency of the ELMs, the times per second these events occur, is an indicator of the amount of energy released from the plasma to the wall. High-frequency ELMs can release low amounts of plasma per eruption, but if the ELMs are less frequent, the plasma and energy released per eruption is high, with a greater probability for damage. Recent research has looked at ways to control and increase the frequency of ELMs, such as with pellet injection or additional magnetic fields at very small magnitudes.

Unterberg’s team found, as they expected, that having the tungsten far from the high-flux strike-point greatly increased the probability of contamination when exposed to low-frequency ELMs that have higher energy content and surface contact per event. Additionally, the team found that this divertor far-target region was more prone to contamination of the scrape-off layer even though it generally has lower fluxes than the strike-point. These seemingly counterintuitive results are being confirmed by ongoing divertor modeling efforts in relation to this project and future experiments on DIII-D.

This project involved a team of experts from across North America, including collaborators from Princeton Plasma Physics Laboratory, Lawrence Livermore National Laboratory, Sandia National Laboratories, ORNL, General Atomics, Auburn University, the University of California at San Diego, the University of Toronto, the University of Tennessee—Knoxville, and the University of Wisconsin–Madison, as it provided a significant tool for plasma-material interaction research. DOE’s Office of Science (Fusion Energy Sciences) provided support for the study.

The team published research online earlier this year in the journal Nuclear Fusion.

The research could immediately benefit the Joint European Torus, or JET, and ITER, now under construction in Cadarache, France, both of which use tungsten armor for the divertor.

“But we’re looking at things beyond ITER and JET — we’re looking at the fusion reactors of the future,” Unterberg said. “Where is it best to put tungsten, and where should you not put tungsten? Our ultimate goal is to armor our fusion reactors, when they come, in a smart way.”

Unterberg said ORNL’s unique Stable Isotopes Group, which developed and tested the enriched isotope coating before putting it in a form useful for the experiment, made the research possible. That isotope would not have been available anywhere but from the National Isotope Development Center at ORNL, which maintains a stockpile of almost every element isotopically separated, he said.

“ORNL has unique expertise and particular desires for this type of research,” Unterberg said. “We have a long legacy of developing isotopes and using those in all kinds of research in different applications around the world.”

In addition, ORNL manages US ITER.

Next, the team will look at how putting tungsten into differently shaped divertors might affect contamination of the core. Different divertor geometries could minimize the effects of plasma-material interactions on the core plasma, they have theorized. Knowing the best shape for a divertor — a necessary component for a magnetic-confined plasma device — would put scientists one step closer to a viable plasma reactor.

“If we, as a society, say we want nuclear energy to happen, and we want to move to the next stage,” Unterberg said, “fusion would be the holy grail.”

UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

Journal

Nuclear Fusion

DOI

10.1088/1741-4326/ab537b

Mangrove forests are long known for storing large amounts of carbon in the trees and soil. In recent times, mangrove deforestation has raised alarms about increased carbon emissions into the atmosphere. However, research shows that the net amount of carbon released from deforestation in the past 20 years is lower than widely believed, thanks to conservation and restoration efforts, and the natural establishment of new mangrove forests.

Over the past decade, mangroves have been the focus of many conservation and restoration projects, aimed at keeping the carbon stock locked up in this coastal ecosystem. Until now, the effects of these actions in preventing mangrove carbon losses was not known. New research led by the Singapore-ETH Centre shows that globally, the net loss of mangrove carbon stocks between 1996 and 2016 is only 1.8% - or less than 0.1% of global CO2 emissions over the same period.

The research is the first to take into account the expansion of mangroves--through natural and human forestation--in quantifying net losses of mangrove carbon stocks. Previous estimates only considered the negative effects of deforestation, but not the possibility that new mangroves would grow. The new method combines improved global datasets on mangrove coverage and carbon densities with new research quantifying how much carbon is typically lost when a mangrove becomes deforested. Using the new method, carbon loss estimates are 66% lower than previous models.

The low net loss of mangrove carbon stocks was surprising, according to Dr Dan Richards, from the Singapore-ETH Centre, who led the research. He is currently the principal investigator of the Natural Capital Singapore project, which is funded by the National Research Foundation of Singapore, under its Campus for Research Excellence and Technological Enterprise (CREATE). "Mangrove deforestation is often portrayed as an ongoing crisis, but our study, among recent pieces of work, show that there has actually been considerable success in slowing down deforestation around the world". In fact, in some parts of Mexico and Myanmar, there was more carbon stored in mangroves in 2016 than in 1996.

Despite the apparent success of conservation efforts in protecting mangroves from deforestation, there is no room for complacency. "Mangroves hold some of the highest densities of carbon in any ecosystem. Effective conservation and restoration still require considerable management effort and investment to maintain these low rates of net loss," said Dr Benjamin Thompson from Monash University, who co-authored the study. Moreover, lessons learnt from mangrove conservation and restoration activities could be extended to benefit other ecosystems. "Tropical peatlands are another ecosystem with large stocks of carbon that have seen high rates of deforestation in recent decades," says Dr Lahiru Wijedasa from the National University of Singapore, who is the final author of the study.

As new infectious diseases emerge and spread, one of the best shots against novel pathogens is finding new medicines or vaccines. But before drugs can be used as potential cures, they have to be painstakingly screened for composition, safety and purity, among other things. Thus, there is an increasing demand for technologies that can characterize chemical compounds quickly and in real time.

Addressing this unmet need, researchers at Texas A&M University have now invented a new technology that can drastically downsize the apparatus used for Raman spectroscopy, a well-known technique that uses light to identify the molecular makeup of compounds.

"Raman benchtop setups can be up to a meter long depending on the level of spectroscopic resolution needed," said Dr. Pao-Tai Lin, assistant professor in the Department of Electrical and Computer Engineering and the Department of Materials Science and Engineering. "We have designed a system that can potentially replace these bulky benchtops with a tiny photonic chip that can snugly fit within the tip of a finger."

In addition, Lin said that their innovative photonic device is also capable of high-throughput, real-time chemical characterization and despite its size, is at least 10 times more sensitive than conventional benchtop Raman spectroscopy systems.

A description of their study is in the May issue of the journal Analytical Chemistry.

The basis of Raman spectroscopy is the scattering of light by molecules. When hit by light of a certain frequency, molecules perform a dance, rotating and vibrating upon absorbing the energy from the incident beam. When they lose their excess energy, molecules emit a lower-energy light, which is characteristic of their shape and size. This scattered light, known as the Raman spectra, contains the fingerprints of the molecules within a sample.

Typical benchtops for Raman spectroscopy contain an assortment of optical instruments, including lenses and gratings, for manipulating light. These "free-space" optical components take a lot of space and are a barrier for many applications where chemical sensing is required within tiny spaces or locations that are hard to reach. Also, benchtops can be prohibitive for real-time chemical characterization.

As an alternative to traditional lab-based benchtop systems, Lin and his team turned to tube-like conduits, called waveguides, that can transport light with very little loss of energy. While many materials can be used to make ultrathin waveguides, the researchers chose a material called aluminum nitride since it produces a low Raman background signal and is less likely to interfere with the Raman signal coming from a test sample of interest.

To create the optical waveguide, the researchers employed a technique used by industry for drawing circuit patterns on silicon wafers. First, using ultraviolet light, they spun a light-sensitive material, called NR9, onto a surface made of silica. Next, by using ionized gas molecules, they bombarded and coated aluminum nitride along the pattern formed by the NR9. Finally, they washed the assembly with acetone, leaving behind an aluminum waveguide that was just tens of microns in diameter.

For testing the optical waveguide as a Raman sensor, the research team transported a laser beam through the aluminum nitride waveguide and illuminated a test sample containing a mixture of organic molecules. Upon examining the scattered light, the researchers found that they could discern each type of molecule within the sample based on the Raman spectra and with a sensitivity of at least 10 times more than traditional Raman benchtops.

Lin noted since their optical waveguides have very fine width, many of them can be loaded onto a single photonic chip. This architecture, he said, is very conducive to high-throughput, real-time chemical sensing needed for drug development.

"Our optical waveguide design provides a novel platform for monitoring the chemical composition of compounds quickly, reliably and continuously. Also, these waveguides can be easily manufactured at an industrial scale by leveraging the already existing techniques to make semiconductor devices," said Lin. "This technology, we believe, has a direct benefit for not just pharmaceutical industries but even for other industries, like petroleum, where our sensors can be put along underground pipes to monitor the composition of hydrocarbons."

A new animation of nighttime imagery from NASA-NOAA's Suomi NPP satellite followed the path of former Hurricane Laura from its landfall in southwestern Louisiana to its movement over the Mississippi Valley.

As Laura tracks across the eastern U.S., it is generating heavy rain and has triggered watches.

On Aug. 28, Flash Flood Watches were posted for portions of northeast Arkansas, southeast Missouri, western Kentucky and Tennessee, northern of Mississippi, and northwest Alabama.

NASA's Night-Time Imagery Tracks Laura

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided days of infrared nighttime imagery of the now former hurricane Laura. Using the Worldview Application at NASA's Goddard Space Flight Center, Greenbelt, Md. an animation was created of nighttime imagery from Aug. 23 to 28, 2020 (0000 UTC) that showed the track of Hurricane Laura from the landfall and movement from southwestern Louisiana to the Mississippi Valley.

Tropical Depression Laura's Status on Aug. 28

At 11 a.m. EDT (1500 UTC) on Aug. 28, NOAA's Weather Prediction Center (WPC) noted the center of Tropical Depression Laura was located near latitude 36.6 north, longitude 90.5 west. That puts the center about 85 miles (140 km) northwest of Memphis, Tenn. and about 105 miles (170 km) west-southwest of Paducah, Kentucky. The depression was moving toward the east-northeast near 20 mph (31 km/h) and this motion is expected to continue as Laura tracks along and south of the Ohio Valley through tonight. Maximum sustained winds were near 30 mph (45 kph) with higher gusts. The estimated minimum central pressure is 1001 millibars.

Hazards Laura Brings Along its Path

NOAA's WPC provided a look at the hazards that Tropical Depression Laura is expected to bring along its path toward the Atlantic Ocean over the next 2 days: "Expect 1 to 3 inches, with isolated 5-inch totals from western and central Kentucky and Tennessee into northern Alabama and Mississippi. One to 2 inches, with isolated 4-inch totals are possible over southern parts of Louisiana, Mississippi, and Alabama. By Saturday, 1 to 3 inches of rain is forecast from the central and southern Appalachians to the Mid-Atlantic States. This rainfall will continue to contribute to isolated flash and urban flooding, and overflow of small streams and creeks across the aforementioned regions. Minor to moderate river flooding is occurring or forecast in Louisiana and Arkansas.

Gusty winds of 25-30 mph will accompany Laura's circulation as it moves toward the Lower Ohio Valley through the afternoon. Stronger gusts are possible within thunderstorms.

A few tornadoes remain possible, mainly over parts of Mississippi, Tennessee and southern Kentucky. The risk for a couple of tornadoes should redevelop Saturday afternoon and evening over parts of the mid-Atlantic from Virginia to North Carolina."

Forecast for Laura

Eventually, the remains of Laura will cross the central Appalachians Saturday, before becoming absorbed by an approaching cold front that is forecast to move off the mid-Atlantic coastline by late Saturday.