Culture

A team of zoologists and microbiologists from NUI Galway have published a new study showing that common house spiders carry bacteria susceptible to infect people, with the Noble False Widow spiders also carrying harmful strains resistant to common antibiotic treatments.

This new research, published in the international journal Scientific Reports, confirms a theory which has been debated among spider and healthcare specialists for many years, and explains a range of symptoms experienced by victims bitten by the invasive noble false widow spider in Ireland and Britain over the past decade.

Australian Black Widows or Funnel Web spiders are well known for their potentially deadly venom, but rare "skin-eating" conditions following seemingly harmless European and North American spider bites were thought to be the result of secondary infections caused by the victim scratching and probing the bite site with contaminated fingers. This new study shows that not only do spiders carry harmful bacteria, but those germs can be transmitted when a spider uses its fangs to bite.

Furthermore, many spiders have been shown to have venom with antibacterial activity and it is often debated as to whether the venom would neutralise bacteria at the bite site, but this also demonstrates, at least for the Noble False Widow, that the venom does not inhibit bacteria.

Dr Aoife Boyd, Director of the Pathogenic Mechanisms Group at NUI Galway's School of Natural Sciences, and senior author of the study, said: "The diversity of microbes never ceases to amaze me. The power to survive and thrive in every environment is shown here by the presence of antimicrobial resistance bacteria even in spider venom. Antimicrobial resistance (AMR) is an urgent and growing problem worldwide. A One Health approach interconnecting human, animal and environmental health is the only way to tackle the problem."

Dr John Dunbar, Zoologist at the Ryan Institute's Venom System Lab in NUI Galway, said: "About 10 species of spiders common in North-western Europe have fangs strong enough to pierce human skin and deliver venom, but only one of them, the recent invasive noble false widow spider, is considered of medical importance. Most of the time, a spider bite results in some redness and pain.

"In some cases, however, victims seem to develop long lasting infections for which strong antibiotic treatment - and sometimes a hospital stay - are necessary. It is this increasing range expansion and massive rise in dense populations of false widow spiders around urbanised areas across Ireland and Britain that has seen a rise in bites with some severe envenomation symptoms but also infections, which in some cases proved even difficult to treat with antibiotics."

Neyaz Kahn, co-lead author of the study and PhD student at the Pathogenic Mechanisms Group in NUI Galway's School of Natural Sciences, said: "Our study demonstrates that spiders are not just venomous but are also carriers of dangerous bacteria capable of producing severe infections. The biggest threat is that some of these bacteria are multi-drug resistant, making them particularly difficult to treat with regular medicine. This is something that health care professionals should consider from now on."

The onset of any physical exercise program causes muscle pain that can hinder movements as simple as getting up from a sofa. With time and a little persistence, the muscles become accustomed to the effort, developing more strength and endurance. Researchers affiliated with Harvard University in the United States and the University of São Paulo (USP) in Brazil describe the cellular mediator that makes this adaptation to exercise possible in the journal Cell.

The mediator is succinate, a metabolite hitherto known only for its participation in mitochondrial respiration. The authors of the article include Julio Cesar Batista Ferreira, a professor at USP's Biomedical Sciences Institute (ICB) and a member of the Center for Research on Redox Processes in Biomedicine (Redoxome), one of the Research, Innovation and Dissemination Centers (RIDCs) funded by FAPESP (São Paulo Research Foundation), and postdoctoral fellow Luiz Henrique Bozi, who conducted the investigation while he was a research intern at Harvard with FAPESP's support.

"Our results show that succinate leaves muscle cells during exercise and sends their neighbors signals that induce a process of muscle tissue remodeling," Ferreira explained to Agência FAPESP. "The motor neurons create new ramifications, the muscle fibers become more uniform to gain strength on contracting, and blood sugar uptake increases in all cells to produce ATP [adenosine triphosphate, the cellular fuel]. There's an increase in efficiency."

The findings reported in the article are based on a large number of experiments with animals and human volunteers. The first entailed comparisons of more than 500 metabolites present in mouse leg muscles before and after the mice ran on a treadmill until they were exhausted.

"Besides muscle fibers, muscle tissue also contains immune, nerve, and endothelial cells. If each one was a house, the streets between houses would be the interstitium or interstitial space. We isolated and analyzed each of the houses as well as the streets to find out what changes in the neighborhood after exercise, and observed a significant increase in succinate only in muscle fibers and interstitial spaces," Ferreira said.

A similar phenomenon was observed in healthy volunteers aged 25-35 during 60 minutes of intense exercise on a stationary bicycle. In this case, the researchers analyzed blood samples obtained via catheters in the femoral artery and vein and found that succinate levels rose substantially in venous blood exiting the muscle and fell rapidly during recovery.

At this point, the researchers were convinced that muscle cells released succinate in response to the stress caused by exercise, but they wanted to find out how, and above all why. Analysis of the volunteers' blood offered a clue: another compound that increased with exercise, in both venous and arterial blood, was lactate (the ionized form of lactic acid), a sign that the cells had activated their emergency energy generation system.

"Succinate is a metabolite that is normally unable to cross the cell membrane and leave the cell. Inside the cell, it participates in the Krebs cycle, a series of chemical reactions that occur in the mitochondria and result in ATP formation," Bozi explained. "But when energy demand increases sharply and the mitochondria can't keep up, an anaerobic system is activated, causing excess lactate formation and cell acidification. We found that this change in pH causes a change in the chemical structure of succinate such that it's able to get through the membrane and escape into the extracellular medium."

The transport protein that helps succinate exit the cell was identified by proteomics, an analysis of all the proteins in the membranes of mouse and human muscle cells. The results showed an increase in MCT1 in muscle tissue after exercise. MCT1 is a protein that specializes in transporting monocarboxylate out of the cell.

"The kind of molecule MCT1 transports is similar to succinate when it undergoes chemical modification in an acid medium. It ceases to be dicarboxylate and becomes monocarboxylate. We performed several in vitro experiments to confirm that this was the mechanism induced by exercise," Bozi said.

One of the experiments consisted of submitting cultured muscle cells to hypoxia (oxygen deprivation) in order to activate the anaerobic energy production mechanism and produce lactate. This was seen to be sufficient to induce succinate release into the interstitial space.

Another experiment involved germ cells (oocytes) from frogs genetically modified to express human MCT1. The researchers found that the oocytes released succinate only when they were placed in an acid medium.

"By this stage, we knew acidity makes succinate undergo protonation, a chemical process that enables it to bind to MCT1 and pass through the membrane into the extracellular medium, but we had yet to discover the significance of this accumulation of succinate in the interstitial space during exercise," Ferreira said.

Communication

The importance of communication between cells in the organism's adaptation to any kind of stress is well-established in the scientific literature. Signals are exchanged by means of molecules released into the interstitial space to bind to proteins in the membranes of nearby cells. Activation of these membrane receptors triggers processes that lead to structural and functional tissue modifications.

"Our hypothesis was that succinate performed this role of regulation in muscles, by binding to a protein called SUCNR1 [succinate receptor 1] that's highly expressed in the membranes of motor neurons, for example," Bozi said.

To test the theory, they conducted experiments with mice that had been genetically modified not to express SUCNR1. The mice were allowed to run freely on a resistance wheel for three weeks, considered long enough for morphological and functional changes to occur in muscle tissue.

"The muscle fibers were expected to become more uniform and stronger, but they didn't," Ferreira said. "In addition, exercise didn't promote motor neuron ramification, which is crucial to enhance contraction efficiency. We also observed that cellular glucose uptake didn't increase and that insulin sensitivity was lower than in the wild mice that served as controls. In other words, exercise-induced remodeling didn't happen without the succinate receptor."

According to Ferreira, the study is the first to show the paracrine action of succinate in muscle tissue, i.e. its role in cell-to-cell signaling to alert nearby cells that they must modify their internal processes to adapt to a "new normal".

"The next step is to find out whether this mechanism is disrupted in other diseases characterized by energy metabolism alterations and cell acidification, such as neurodegenerative diseases, in which astrocyte-neuron communication is critical to disease progression," he said.

COLUMBIA, Mo. -- After Jo-Ana Chase heard her mother had successful heart surgery, she was relieved when her mom was finally discharged from the hospital and sent home to be cared for by her brother. However, Chase quickly learned from her brother that he felt lost on the best ways to care for their mom due to confusing discharge instructions from the hospital and logistical challenges related to home health care services like wound care and medication management.

Motivated by her own family's struggles navigating the often complicated American health care system, Chase, an associate professor in the University of Missouri's Sinclair School of Nursing, is working with clinicians and health care providers to better engage family caregivers in providing coordinated care after a loved one is discharged home from the hospital. In a recent study, she sought to better understand the resources family caregivers currently use to help health care providers identify gaps in coverage and recommend resources to assist overburdened caregivers and ultimately improve and better coordinate care.

"The American health care system has been very patient-focused; however, we also need to remember that patients often rely on family for help with their care," Chase said. "Now that we are starting to recognize how impactful the work is that family caregivers provide, my goal is to better engage these family caregivers and help them access the resources they need to better support the loved ones they care for."

In her study, Chase interviewed family caregivers about the medical and nursing tasks they completed for a loved one after a hospital-to-home transition, such as treating wounds or giving medication. She found that family caregivers often struggle with these tasks and in navigating the complex health care system; and resources like home health care nurses or aides can serve as a central point-of-contact to improve coordinated care.

"After a patient is discharged from the hospital, a home health care nurse will often come to the patient's home periodically to check in, make sure the medications are right, evaluate the home for safety, check the patient's vital signs and assess wounds," Chase said. "This is an excellent opportunity for the clinicians to work with caregivers to address any questions, challenges, or concerns family caregivers may be having."

Chase added that while caregivers may receive discharge instructions for providing care after a patient leaves the hospital, the instructions may fail to consider caregivers' preparedness and various environmental factors, such as what equipment is needed, or which room in a house is best for administering a specific task like changing a bandage. In addition to home health care nurses, primary care providers, social workers, nearby community centers and respite services can also help support and take the load off of overburdened caregivers.

"At some point in our lives, most of us will become a caregiver for someone, whether it is a child, spouse, parent or relative," Chase said. "So, encouraging the health care system to effectively engage caregivers benefits us all. I hope one day when I am sick and someone has to take care of me, my caregiver doesn't experience the same challenges my brother did caring for my mom."

The COVID-19 pandemic has sparked heightened awareness of cleaning and disinfecting procedures in many industries. Health care facilities have long been familiar with protocols for disinfecting tools and equipment, and now, scientists are studying methods to improve these procedures, making them safer and more efficient for patients and health care workers.

At Johns Hopkins, biomedical engineer Jeff Siewerdsen and radiologist Mahadevappa Mahesh are investigating the use of UV light to disinfect the inner bore of CT scanning machines, a cramped space that is exposed to exhaled particles from patients and is difficult to reach by manually wiping it down.

The UV light being studied is not the typical beam of sunshine that falls to the earth. Those rays are mostly UVA rays, which tend to cause skin cancer and other problems. Siewerdsen and Mahesh are studying UVC rays, which can eliminate a high proportion of SARS-CoV-2 virus from hard surfaces.

They attached a UVC lamp to the bed inside the bore of a CT scanner and found that the UV light wiped out 99.9999% of SARS-CoV-2 virus particles in three to five minutes. A summary of the results was published Nov. 18, along with a video abstract, in the Journal of Applied Clinical Medical Physics.

The lamp used in the study cost $105; however, they did not study the longevity of the lamp. The researchers also note that there may be crevices in the CT scanner that are not reachable with the UV light.

If the UVC procedure for CT scanners proves useful, the process could be used in addition to the manual wipe down of CT scanners, improve the safety of personnel and patients, and applicable to many health care facilities around the globe.

Note: Exposure to UVC light could harm health. UVC lamps should not be used without proper training and safety precautions. Read more information from the FDA.

DOES PROLONGED COVID-19 DETECTION IDENTIFY PEOPLE WHO ARE INFECTIOUS LONG TERM?

Media Contact: Michael E. Newman, mnewma25@jhmi.edu

Repeated testing for SARS-CoV-2, the virus that causes COVID-19, has become common practice during the ongoing pandemic, especially when there is a strong suspicion that a person is infected with, or has been exposed to, the pathogen. Molecular diagnostics are the standard means for detecting the presence of SARS-CoV-2 genetic material (RNA), with negative assays from two consecutively collected respiratory specimens more than 24 hours apart and no symptoms being the benchmark for when a patient can end quarantine and return to normal activities.

However, recent research has shown that while SARS-CoV-2 RNA can be detectable with molecular testing for weeks after the onset of symptoms, it doesn't necessarily denote the presence of infectious virus particles. In a medical records study looking at results from nearly 30,000 COVID-19 tests over a two-month period, a team led by researchers at Johns Hopkins Medicine and the Johns Hopkins Bloomberg School of Public Health gained significant insight into when virus detection also may indicate contagiousness.

The findings were published online Oct. 27 in the journal Clinical Infectious Diseases.

From March 11 to May 11, 2020, the researchers evaluated the results of repeated polymerase chain reaction (PCR) diagnostic tests for SARS-CoV-2 RNA in 29,686 nasopharyngeal swabs. The PCR assay is very specific and detects the viral RNA by accumulation of a fluorescent signal. The number of times it takes to get a positive signal is called the cycle threshold (Ct), with a low Ct score indicating a large amount of SARS-CoV-2 RNA and a high one just the opposite.

"We also placed a portion of the specimens in cell cultures to see whether or not live virus particles would grow," says Heba Mostafa, M.B.B.Ch., Ph.D., assistant professor of pathology at the Johns Hopkins University School of Medicine and co-senior author of the study. "In that way, we could compare the Ct values with actual virus recovery in the lab to see when detected virus also was infectious virus."

The researchers found that the average Ct value associated with cell culture growth of SARS-CoV-2 was 18.8. They also observed viral growth from specimens collected up to 20 days after the first positive result, mostly in patients who were symptomatic for COVID-19 at the time of specimen sampling. Sequencing of the entire genome from RNAs collected in the first and subsequent tests provided evidence that the same virus was seen throughout. Positive tests following negative ones had Ct values higher than 29.5 and were not associated with observed virus growth in culture.

"Our findings support the theory that low Ct values in SARS-CoV-2 diagnostic tests are associated with recoverable virus, and that RNA detection in repeated tests may indicate someone who continues to be infectious with persistent symptoms," Mostafa says. "However, additional studies are needed to truly determine if Ct values and cell cultures can be used together to make clinical decisions, develop diagnostic strategies and identify those most likely to spread SARS-CoV-2."

"Defining the window of time in which a COVID-19 patient can transmit the virus can help drive more effective isolation practices," adds Andrew Pekosz, Ph.D., professor of microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health and co-senior author of the study.

CLEVELAND--A team of researchers at the Case Western Reserve University School of Medicine has taken a major step toward understanding the mechanisms involved in the formation of large clumps of tau protein, a hallmark of Alzheimer's disease and several other neurodegenerative disorders.

Their findings may help to better understand the pathological process and possibly lead to developing medications to treat such devastating brain diseases.

The study, "Regulatory mechanisms of tau protein fibrillation under the conditions of liquid-liquid phase separation," was published this week in the journal Proceedings of the National Academy of Sciences.

The senior author of the study is Witold Surewicz, a professor of physiology and biophysics at the School of Medicine. Solomiia Boyko, a graduate student, and Krystyna Surewicz, a senior research associate, co-authored the study, which was supported by the National Institute on Aging.

Alzheimer's disease is characterized by the death of nerve cells in the brain, resulting in progressive memory loss and cognitive decline. More than 5 million people in the United States suffer from Alzheimer's, and this number is projected to triple by 2050, according to the Alzheimer's Association. There is no cure for this devastating disease.

In Alzheimer's disease, clumps of a tau protein begin to form inside nerve cells in the brain. Brain accumulation of these aggregates are known as "neurofibrillary tangles."

Similar tangles of tau, which spread among nerve cells, are also associated with a host of other neurodegenerative diseases, collectively known as "tauopathies." These include Pick's disease, frontotemporal dementia, progressive supranuclear palsy and chronic traumatic encephalopathy.

Recent studies have demonstrated that, like some other proteins, tau can undergo liquid-liquid phase separation, a process resulting in formation of liquid-like droplets containing highly concentrated protein. This phenomenon, similar to how oil and water separate when mixed, is believed to be important for normal functions of cells. However, under certain conditions, this separation within cells may also have pathological consequences.

The new study establishes a critical link between these two phenomena--tau liquid-liquid phase separation and tangle formation--demonstrating that the environment of liquid droplets greatly facilitates aggregation of tau into fibrillar structures similar to those found in the brain of someone with Alzheimer's disease.

The researchers also describe the mechanism by which this liquid-liquid phase separation regulates clumping when different variants of tau protein are present. In particular, the authors show that, because of the unique properties of liquid droplets, the presence of a shorter, slowly aggregating tau variant inhibits clumping of a longer, normally fast aggregating variant, slowing down the overall process of tangle formation.

This novel regulatory mechanism may play a major role in determining the clinical outcome of the disease, as the ratio of these two tau variants in brain varies substantially in different tauopathies.

For example, Alzheimer's disease is usually characterized by an equal proportion of both tau isoforms, whereas fibrillary tangles in progressive supranuclear palsy and Pick's disease consist largely of the longer and shorter variant, respectively.

"While the present results provide exciting new insights into formation of pathological clumps of tau protein," Surewicz said, "our study was limited to experiments with purified proteins in the test tube. The next step is to verify these findings in cell and animal models of the disease."

UNIVERSITY PARK, Pa. -- Imagine changing the TV channel with a wave of your hand or turning on the car radio with a twist of your wrist.

Freehand gesture-based interfaces in interactive systems are becoming more common, but what if your preferred way to gesture a command - say, changing the TV to channel 10 - significantly differed from that of a user from another culture? Would the system recognize your command?

Researchers from the Penn State College of Information Sciences and Technology and their collaborators explored this question and found that some gesture choices are significantly influenced by the cultural backgrounds of participants.

"Certain cultures may prefer particular gestures and we may see a difference, but there is common ground between cultures choosing some gestures for the same kind of purposes and actions," said Xiaolong "Luke" Zhang, associate professor of information sciences and technology and principal investigator of the study. "So we wanted to find out what can be shared among the different cultures, and what the differences are among different cultures to design better products."

In their study, the researchers asked American and Chinese participants to perform their preferred gestures for different commands in three separate settings: answering a phone call in the car, rotating an object in a virtual reality environment, and muting the television.

The team found that while many preferred commands were similar among both cultural groups, there were some gesture choices that differed significantly between the groups. For example, most American participants used a thumbs up gesture to confirm a task in the virtual reality environment, while Chinese participants preferred to make an OK sign with their fingers. To reject a phone call in the car, most American participants made a horizontal movement across their neck with a flat hand, similar to a "cut" motion, while Chinese participants waved a hand back and forth to reject the call. Additionally, in Chinese culture, one hand can represent digits above five, while in American culture an individual can only represent numbers one to five using one hand.

"This project is one of the first kind of research to study the existence of cultural influence and the use of preferences of hand gestures," said Zhang. "We provide empirical evidence to show indeed that we should be aware of the existence of this matter."

On the other hand, Zhang said, from the perspective of design, the study shows that certain gestures can be common across multiple cultures, while other gestures can be very different.

"Designers have to be careful when delivering products to different markets," he said. "(This work could inform companies) to enable users customize the gesture commands, rather than have them pick something that is unnatural to learn from the perspective of the culture."

As time goes by, the tips of your chromosomes--called telomeres--become shorter. This process has long been viewed as an unwanted side-effect of aging, but a recent study shows it is in fact good for you.

"Telomeres protect the genetic material," says Titia de Lange, Leon Hess Professor at Rockefeller. "The DNA in telomeres shortens when cells divide, eventually halting cell division when the telomere reserve is depleted."

New results from de Lange's lab provide the first evidence that telomere shortening helps prevent cancer in humans, likely because of its power to curtail cell division. Published in eLife, the findings were obtained by analyzing mutations in families with exceptional cancer histories, and they present the answer to a decades-old question about the relationship between telomeres and cancer.

A longstanding controversy

In stem cells, including those that generate eggs and sperm, telomeres are maintained by telomerase, an enzyme that adds telomeric DNA to the ends of chromosomes. Telomerase is not present in normal human cells, however, which is why their telomeres wither away. This telomere shortening program limits the number of divisions of normal human cells to about 50.

The idea that telomere shortening could be part of the body's defense against cancer was first proposed decades ago. Once an early-stage tumor cell has divided 50 times, scientists imagined, depletion of the telomere reserve would block further cancer development. Only those cancers that manage to activate telomerase would break through this barrier.

Clinical observations seemed to support this hypothesis. "Most clinically detectable cancers have re-activated telomerase, often through mutations," de Lange says. Moreover, mouse experiments showed that shortening telomeres can indeed protect against cancer. Nonetheless, evidence for the telomere tumor suppressor system remained elusive for the past two decades, and its existence in humans remained controversial.

The solution to a decades-old problem

The telomere tumor suppressor pathway can only work if we are born with telomeres of the right length; if the telomeres are too long, the telomere reserve would not run out in time to stop cancer development. Longer telomeres will afford cancer cells additional divisions during which mutations can creep into the genetic code, including mutations that activate telomerase.

For decades, de Lange's lab has been studying the complex process by which telomeres are regulated. She and others identified a set of proteins that can limit telomere length in cultured human cells, among them a protein called TIN2. When TIN2 is inhibited, telomerase runs wild and over-elongates telomeres. But it was not known whether TIN2 also regulated telomere length at birth.

The stalemate on the telomere tumor suppressor continued until physicians at the Radboud University Medical Center in Holland reached out to de Lange about several cancer-prone families.  The doctors found that these families had mutations in TINF2, the gene that encodes the TIN2 protein instrumental to controlling telomere length. That's when they asked de Lange to step in.

Isabelle Schmutz, a Women&Science postdoctoral fellow in the de Lange lab, used CRISPR gene-editing technology to engineer cells with precisely the same mutations as those seen in the Dutch families and examined the resulting mutant cells. She found that the mutant cells had fully functional telomeres and no genomic instability. They were, for all intents and purposes, normal healthy cells.

But there was one thing wrong with the cells. "Their telomeres became too long, " de Lange says.  Similarly, the patient's telomeres were unusually long. "These patients have telomeres that are far above the 99th percentile," de Lange says.

"The data show that if you're born with long telomeres, you are at greater risk of getting cancer, " says de Lange. "We are seeing how the loss of the telomere tumor suppressor pathway in these families leads to breast cancer, colorectal cancer, melanoma, and thyroid cancers. These cancers would normally have been blocked by telomere shortening. The broad spectrum of cancers in these families shows the power of the telomere tumor suppressor pathway."

The study is demonstration of the power of basic science to transform our understanding of medicine. "How telomeres are regulated is a fundamental problem," de Lange says. "And by working on a fundamental problem, we were eventually able to understand the origins of a human disease."

A rupture along the full length of the fast-slipping Alpine Fault on New Zealand's South Island poses the largest potential seismic threat to the southern and central parts of the country. But new evidence of a 19th century earthquake indicates that in at least one portion of the fault, smaller earthquakes may occur in between such large rupture events.

The findings published in the Bulletin of the Seismological Society of America suggest that some places along the fault, particularly around the towns of Hokitika and Greymouth, could experience strong ground shaking from Alpine fault earthquakes more often than previously thought.

The best paleoseismic evidence to date suggests the southern and central sections of the Alpine Fault, at the boundary separating the Australian and Pacific tectonic plates, typically rupture during very large full-section earthquakes of magnitude 7.7 or larger. The last such earthquake took place in 1717.

After trenching along the fault at the Staples site near the Toaroha River, however, Robert Langridge of GNS Science and colleagues uncovered evidence of a more recent earthquake along the northeastern end of the fault's central portion. Radiocarbon dating places this earthquake between 1813 and 1848.

"One of the real challenges with the Alpine Fault--because it is so bush-covered--is actually finding sites that have been cleared and therefore can be studied," said Langridge. "Once we started working there [at the Staples site] the story really grew in large part because of the richness of dateable organic material in the trenches."

The four most recent earthquakes uncovered by the researchers at the site range in dates from 1084 to 1848. The events were confirmed by data collected from other nearby trenching sites and from geological deposits called turbidites, which are sediments shaken loose into a body of water by seismic activity, in lakes along the central section of the Alpine fault.

The most recent earthquake could represent a "partial-section" rupture of only the central portion of the Alpine fault, a rupture of the fault's northern section that continued southwest into the central segment, or even triggered slip from a rupture along the nearby Marlborough Fault System. Langridge and colleagues said that there isn't enough evidence yet to favor one of these scenarios over the others.

However, the findings do suggest that seismic activity on the Alpine Fault is more complex than suspected, particularly along its northern reaches where the plate boundary transitions into another fault zone.

"One of the outcomes of this study is that you should expect a shorter recurrence interval of strong shaking at fault section ends," Langridge said. "Because of the recurrence times of earthquakes though, you obviously have to wait a long time to see the effects of such fault behavior."

"That's why paleoseismology is a vital tool in understanding faults," he added, "because otherwise we'd have only short insights into the past."

The Alpine Fault is sometimes compared with California's San Andreas Fault, being another fast-moving strike slip fault near a plate boundary. Langridge said researchers in California and New Zealand have a long history of earthquake science collaboration and are learning from each other about the treatment of active faults and fault segmentation for seismic hazard models.

"The San Andreas Fault, being on the opposite side of the Pacific plate, it is like our distant brother or whanau--family," said Langridge.

COLUMBUS, Ohio - Widespread forest management and protections against deforestation can help mitigate climate change - but will come with a steep cost if deployed as broadly as policymakers have discussed, new research suggests.

The study, published today in the journal Nature Communications, found that planting and protecting trees, especially in the tropics, could reduce carbon dioxide emissions by as much as 6 gigatons a year from 2025 to 2055. That reduction, the researchers' economic model showed, would cost as much as $393 billion a year over the same time period.

"There is a significant amount of carbon that can be sequestered through forests, but these costs aren't zero," said Brent Sohngen, co-author of the study and a professor of environmental economics at The Ohio State University.

A 6-gigaton reduction by 2055 would amount to about 10 percent of the total reduction needed to keep the climate from warming beyond 1.5 or 2 degrees Celsius. Policymakers and scientists agree that humans worldwide need to put strategies in place that will keep the climate from warming above that threshold.

Limiting warming by that amount would not mean climate change is solved. At a 2-degree increase, for example, extreme heatwaves will become widespread, droughts would plague many urban environments around the world, and heavy rainfalls - including those from tropical storms or hurricanes - would become more commonplace. Many insects and animals would also die.

Those levels, though, would allow for some adaptation, according to the Intergovernmental Panel on Climate Change, the United Nations body that is trying to help the world address climate change. The world is currently on pace to warm by about 4 degrees.

A number of recent studies have suggested that tree planting, management and conservation can solve a significant share of the world's climate problem, but most studies have ignored the costs. This analysis updated the Global Timber Model, which considers potential climate change policies and the effects they would have on forest land use, management and trade. The model allowed the researchers to calculate the worldwide financial costs of sequestering carbon in the world's forests.

The researchers found that protecting existing forests is cheaper than planting new ones, and that forest management, including changing how and when trees are harvested, provides low-cost options to store carbon in regions where timber management is an important economic activity.

One important reason why the costs in this study are higher than other estimates is because researchers captured carbon leakage, which occurs if carbon emissions shift to other sectors or geographic areas. For example, if planting trees in one location on agricultural land causes additional deforestation somewhere else, the net change in carbon will be smaller because of this leakage.

The study illustrates the geography and timing of the costs of forestry actions to mitigate climate change. Specifically, the researchers found forests in Brazil, the Democratic Republic of Congo and Indonesia are likely to contribute the greatest possible carbon sequestration efforts at the lowest costs. Protecting tropical forest land in the short term gives way to planting and managing tropical and temperate forests, often with longer rotations, to maintain high levels of mitigation beyond 2050.

"Protecting, managing and restoring the world's forests will be necessary for avoiding dangerous impacts of climate change, and have important co-benefits such as biodiversity conservation, ecosystem service enhancement and protection of livelihoods," said Kemen Austin, lead author of the study and senior policy analyst with RTI International, a nonprofit research institute based in North Carolina. "Until now, there has been limited research investigating the costs of climate change mitigation from forests. Better understanding the costs of mitigation from global forests will help us to prioritize resources and inform the design of more efficient mitigation policies."

The researchers also found that in the temperate and subarctic regions, the United States would likely be responsible for the greatest share of forest-related carbon mitigation efforts - about 24 percent of the possible mitigation in those climate regions would come from the United States based on forested and deforested land. China and Canada have the potential to contribute significantly, too, the researchers found.

And managing the world's forests would be only one piece of the broader puzzle. Energy sources that don't rely on fossil fuels - things like solar and wind power - likely will play the largest role in any climate change mitigation strategy.

"What we see is that you should devote about a third of your effort to this stuff and two-thirds to the other stuff - to reducing coal, to investing in solar, to switching to electric," Sohngen said. "If you want your total mitigation to be as cheap as possible, that's what you would do."

CORVALLIS, Ore. -- Tobacco control efforts have reduced cigarette smoking for many, but those efforts have disproportionately helped white smokers, while other racial and ethnic groups are still struggling, an Oregon State University researcher's analysis found.

The study, published recently in the journal Nicotine & Tobacco Research, compared cigarette use among racial and ethnic groups. Across all groups, the number of cigarettes consumed per day dropped roughly 30% between 1992 and 2019.

However, the reduction in cigarette use was highest for non-Hispanic whites, an indication that the tobacco control policies implemented over the last 25 years have benefited this group more than others, said Kari-Lyn Sakuma, lead author on the study and an assistant professor in OSU's College of Public Health and Human Sciences.

"I think the biggest takeaway is that while there's been major advances in reducing cigarette use, and in death and sickness associated with cigarettes, we still have a long way to go, particularly as we start to look at who benefited the most from these major efforts to reduce the impact of cigarettes on health," Sakuma said.

"We can see dramatic decreases among white populations. But when you start looking at racial and ethnic groups, and examining more closely the different cigarette use behaviors, it gives us clues as to where the disparities exist and where we can do better to target our public health efforts."

The study compared cigarette use among African Americans, Asian/Pacific Islanders, Hispanics/Latinos, American Indian/Alaskan Natives and non-Hispanic whites, as these were the racial and ethnic groups delineated by the U.S. Census Bureau's Current Population Survey.

Researchers compared results for each group in the U.S. as a whole with each group's results in California specifically. California was chosen as a state that has been at the forefront in legislation and intervention to curb tobacco use, and the data shows cigarette use there has declined more sharply than the U.S. average, across all groups.

Researchers looked at the change over time in how many cigarettes smokers said they smoked each day and how many days they smoked; the rate of uptake, or how many people started smoking for the first time; and how many people successfully quit smoking.

Sakuma has been studying the disparate impact of tobacco use among specific racial and ethnic groups for years. She said tobacco companies have poured lots of money into advertising and marketing their products specifically in low-income neighborhoods and in African American and Hispanic/Latino neighborhoods. These companies also invest significant funds in countering public health policies that could help protect communities.

Lower income neighborhoods have fewer resources to combat these messages, especially because most tobacco control measures start with local pressure -- such as communities pushing to ban cigarette billboards near schools.

"In other communities, there's other things that they need to fight for. While one community may have the task force and resources to create policies to reduce advertising around schools, other folks in lower-income areas are fighting for their schools to remain open," Sakuma said. "It's a difference in ability to address these issues."

Communities with more resources can also afford to fight court battles with tobacco companies and raise public awareness around ballot measures seeking to reduce cigarette use.

Moving forward, Sakuma said, policy makers should prioritize public health efforts that use the study results to tailor public health messaging and outreach for racial and ethnic groups that could benefit more fully from the tobacco control measures of the last few decades.

"We've been successful in the past, but we have to maintain that success while targeting some efforts and distributing more resources among higher-risk groups or more vulnerable communities," she said.

ITHACA, NY, December 1, 2020 -- Thousands of years ago, people in South America began domesticating Solanum pimpinellifolium, a weedy plant with small, intensely flavored fruit. Over time, the plant evolved into S. lycopersicum - the modern cultivated tomato.

Although today's tomatoes are larger and easier to farm compared with their wild ancestor, they also are less resistant to disease and environmental stresses like drought and salty soil.

Researchers from Boyce Thompson Institute, led by Zhangjun Fei, created a high-quality reference genome for S. pimpinellifolium and discovered sections of the genome that underlie fruit flavor, size and ripening, stress tolerance and disease resistance. The results were published in Nature Communications on November 16.

"This reference genome will allow researchers and plant breeders to improve traits like fruit quality and stress tolerance in the tomato," said Fei, "for example, by helping them discover new genes in the modern tomato as well as by reintroducing genes from S. pimpinellifolium that were lost over time as S. lycopersicum was domesticated."

Fei is a BTI faculty member and co-corresponding author on the paper, as well as an adjunct professor in Cornell University's School of Integrative Plant Science (SIPS).

Although other groups had previously sequenced S. pimpinellifolium, Fei said this reference genome is more complete and accurate, thanks in part to cutting-edge sequencing technologies that are able to read very long pieces of DNA.

"Older sequencing technologies that read short pieces of DNA can identify mutations at the single-base level," said Shan Wu, a postdoctoral scientist in Fei's lab and co-corresponding author on the paper. "But they aren't good at finding structural variants, like insertions, deletions, inversions or duplications of large chunks of DNA."

"Many known traits of the tomato are caused by structural variants, so that is why we focused on them," Fei said. "Structural variants also are understudied because they are more difficult to identify."

Fei's group compared their S. pimpinellifolium reference genome to that of the cultivated tomato, called Heinz 1706, and found more than 92,000 structural variants.

The researchers then combed the tomato pan-genome, a database with the genomes of more than 725 cultivated and closely related wild tomatoes, and discovered structural variants related to many important traits. For example, the modern cultivated tomato has some genomic deletions that reduce their levels of lycopene, a red pigment with nutritional value, and an insertion that reduces their sucrose content.

Jim Giovannoni, BTI faculty member and co-author of the study, notes that many consumers are disappointed in the quality and flavor of modern production tomatoes because past breeding efforts ignored those traits in favor of performance and yield.

"Identification of the additional genetic diversity captured in the S. pimpinellifolium genome provides breeders with opportunities to bring some of these important features back to store-bought tomatoes," said Giovannoni, who is also an adjunct professor in SIPS and a scientist with the U.S. Department of Agriculture's Agricultural Research Service.

The researchers found many other structural variants that could be of interest to plant breeders, including variants in numerous disease-resistance genes and in genes involved in fruit size, ripening, hormonal regulation, metabolism, and the development of flowers, seeds and leaves.

The group also found structural variants associated with regulating the expression of genes involved in the biosynthesis of lipids in fruit skin, which could help improve the fruit's post-harvest performance.

"So much genetic diversity was lost during tomato domestication," Fei said. "These data could help bring some of that diversity back and result in tomatoes that taste better, are more nutritious and more resilient."

As case rates of COVID-19 reach new heights across the nation, many states and cities are tightening stay-at-home restrictions to stop the spread. New research suggests that that those suffering from economic hardships are less likely comply with new stay-at-home orders; however, these same U.S. residents would be more likely to adhere to the new public health guidelines if their households received stimulus funds.

The results, published in the Journal of Economic Behavior & Organization, suggest that of the measures taken to address economic dislocation caused by the COVID-19 pandemic, the CARES Act helped reduce an important source of viral spread: social interaction.

In the new paper, researchers from the University of California San Diego School of Global Policy and Strategy and the University of Chicago Harris School of Public Policy sought to accurately measure public willingness to abide by shelter-in-place ordinances first introduced in spring of 2020.

The researchers examined large quantities of geolocated cellular phone device use patterns. The data, provided by the analytics company UNACAST, estimates information such as the number of people who are living in a home, the average time spent at home or outside, and changes in the average distance a user traveled. This information helped the researchers assess compliance with stay-at-home orders.

To determine how economic conditions shape compliance, the researchers compared the cell-phone data to county records containing average household incomes for every county across the U.S. from February through July 2020. They also took account of other factors that might influence county residents' willingness to comply, including how severely each county was hit by the virus, unemployment levels, population density, partisanship and where residents get their news.

Counties with above median income comply with shelter-in-place policies with reducing movement by an additional 60% compared to before the policies were introduced; however, compliance with shelter-in-place orders in counties where the average income is below the median is uneven at best.

"Not surprisingly, impoverished communities exposed to economic dislocation are the least likely to comply with shelter-in-place policies," said co-author Jesse Driscoll, associate professor of political science at UC San Diego's School of Global Policy and Strategy. "The data showed that working-class families -- especially those who had lost jobs or might soon lose them -- were overall much less likely to stay home, since they needed to leave the house to work. The more urgent public policy question going into this winter is whether these behaviors changed when stimulus checks arrived last time."

To assess how stimulus checks from the $2.2 trillion CARES Act, passed in March 2020, impacted compliance, the researchers used the same cellphone movement data to determine whether household income increases changed behavior as more of a county's residents began receiving stimulus payments.

While some beneficiaries received their checks weeks ahead of when others, the team were able to measure the impact stimulus dollars had on residents from data of recipients who used an electronic banking to deposit the funds, made available by the financial data company Facteus.

The researchers found that local stimulus injections significantly increased social distancing. For every additional dollar per capita a county received, movement temporarily declined by over 1 percent.

"As counties received more stimulus funds, their residents stayed home more," the authors write. "When they did head out, people in counties where most had received stimulus checks traveled less than people in counties where most checks had not yet arrived."

The authors conclude, "Targeted economic relief such as direct stimulus transfers and increased unemployment benefits may have limited potential spread of COVID-19 among economically disadvantaged populations."

PHILADELPHIA (December 1, 2020) - More than 90 percent of human papillomavirus (HPV)-related cancers could be prevented by widespread uptake of the HPV vaccine. Yet, vaccine use in the United States falls short of public health goals.

In an article in JMIR Nursing, researchers explain how they applied user-centered design principles to develop a mobile health (mhealth) app to improve HPV vaccine uptake and how its use was evaluated with parents and parent-adolescent dyads. The app -- Vaccipack -- is exclusively focused on adolescent vaccines and targets key parental beliefs related to HPV vaccines. The mhealth app is designed for parents (to use and share with their adolescents) to promote the initiation and completion of the HPV vaccine series in their adolescent children.

The study from the University of Pennsylvania School of Nursing (Penn Nursing) evaluated the acceptability of and intention to use the app. It found that intention to use the app was high among both parents and adolescents after being introduced to the app and given time explore it.

"Theory-based content design, although standard practice in behavioral intervention research, has not been a typical approach adopted by app developers," says Anne M. Teitelman, PhD, FNP-BC, FAANP, FAAN, Associate Professor Emerita of Nursing at Penn Nursing. "Evaluation of acceptability and likely use, as we present here, is an important preliminary step for developing apps and in designing behavioral interventions that are most likely to achieve the desired health outcome." Teitelman is the lead investigator of the study and among the developers of the app.

Millions of sperm enter the race to fertilize, but only one wins the sprint to the egg.

Now Yale researchers have discovered that these winning sperm possess a few key molecular characteristics that differentiate them from those left behind, they report Dec. 1 in the journal eLife.

Sperm tails are lined with channels containing pores for entry of calcium which help sperm move through the female reproductive tract. Each pore of these calcium channels is comprised of four subunits, CatSper 1 through 4, which work together to serve functions such as controlling the mobility and navigation of the sperm.

Researchers playfully describe them as the sperm's racing stripes.

A team of Yale scientists led by Jean-Ju Chung, assistant professor of cellular and molecular physiology, found one of the subunits that form these racing stripes is critical in sperm selection for fertilization.

Using 3D molecular imaging and artificial neural network modeling, Chung's lab devised a way to visually track and quantify sperm in the reproductive tracts of female mice after mating. They discovered that the sperm which advanced from uterus to oviduct had the channels containing intact Catsper1 subunit. Other sperm likely lost functioning CatSper ion channels by losing intact CatSper1. These sperm become immobile and are left behind.

Sperm that make it far into the female reproductive tract share other characteristics: they tend to have already lost a cap-like structure called the acrosome in the sperm head, likely a prelude to fertilizing the egg.

The insights into molecular signatures of sperm and interactions within the reproductive tract may help inform new treatments for infertility or conversely, male birth control. Mutations have been found in the CatSper genes of infertile men and could be a target for fertility treatments. Since the CatSper channel is necessary for sperm to function, blocking it could lead to development of non-hormonal contraceptives with minimal side effects in both men and women, Chung said.

"Better understanding how the fittest sperm cells are selected and how those left are eliminated after fertilization in the female reproductive tract can improve current strategies for assisted reproduction," Chung said.

As cars keep getting smarter, automation is taking many tricky tasks --?from parallel parking to backing up --?out of drivers' hands.

Now, a University of Toronto Engineering study is underscoring the importance of drivers keeping their eyes on the road -- even when they are in an automated vehicle (AV).

Using an AV driving simulator and eye-tracking equipment, Professor Birsen Donmez and her team studied two types of in-vehicle displays and their effects on the driving behaviours of 48 participants.

The findings, published recently in the journal Accident Analysis & Prevention, revealed that drivers can become over-reliant on AV technology. This was especially true with a type of in-vehicle display the team coined as takeover request and automation capability (TORAC).

A "takeover request" asks the driver to take vehicle control when automation is not able to handle a situation; "automation capability" indicates how close to that limit the automation is.

"Drivers find themselves in situations where, although they are not actively driving, they are still part of the driving task -- they must be monitoring the vehicle and step in if the vehicle fails," says Donmez.

"And these vehicles fail, it's just guaranteed. The technology on the market right now is not mature enough to the point where we can just let the car drive and we go to sleep. We are not at that stage yet."

Tesla's AV system, for example, warns drivers every 30 seconds or less when their hands aren't detected on the wheel. This prompt can support driver engagement to some extent, but when the automation fails, driver attention and anticipation are the key factors that determine whether or not you get into a traffic accident.

"Even though cars are advertised right now as self-driving, they are still just Level 2, or partially automated," adds Dengbo He, postdoctoral fellow and lead author. "The driver should not rely on these types of vehicle automation."

In one of the team's driving scenarios, the participants were given a non-driving, self-paced task -- meant to mimic common distractions such as reading text messages -- while takeover prompts and automation capability information were turned on.

"Their monitoring of the road went way down compared to the condition where these features were turned off," says Donmez. "Automated vehicles and takeover requests can give people a false sense of security, especially if they work most of the time. People are going to end up looking away and doing something non-driving related."

The researchers also tested a second in-vehicle display system that added information on surrounding traffic to the data provided by the TORAC system, called STTORAC. These displays showed more promise in ensuring driving safety.

STTORAC provides drivers with ongoing information about their surrounding driving environment, including highlighting potential traffic conflicts on the road. This type of display led to the shortest reaction time in scenarios where drivers had to take over control of the vehicle, showing a significant improvement from both the TORAC and the no-display conditions.

"When you're not driving and aren't engaged, it's easy to lose focus. Adding information on surrounding traffic kept drivers better engaged in monitoring and anticipating traffic conflicts," says He, adding that the key takeaway for designers of next-generation AVs is to ensure systems are designed to keep drivers attentive. "Drivers should not be distracted, at least at this stage."

Donmez's team will next look at the effects of non-driving behaviours on drowsiness while operating an AV. "If someone isn't engaged in a non-driving task and is just monitoring the road, they can be more likely to fall into states of drowsiness, which is even more dangerous than being distracted."