Tech

A team of geoscience researchers in the Virginia Tech College of Science has developed a new theory to explain how and why injection-induced earthquakes continue to occur even when injection rates decline.

Experts have known since the 1960s that when oilfield wastewater is pumped into the ground with deep injection wells, earthquakes can occur. Over the past decade, injection-induced earthquakes have become regular occurrences throughout oil and gas basins worldwide, particularly in the central United States, and potentially in China and Canada, as well.

Oil and gas production are often accompanied by highly brackish groundwater, also known as oilfield brine. These fluids can be five to six times saltier than seawater, so they are toxic to terrestrial ecosystems and have little beneficial use. As a result, oilfield brine is considered to be a waste product that is disposed of by pumping it back into deep geologic formations.

When fluids are pumped into deep injection wells, they alter the naturally occurring fluid pressure in deep geologic formations. These fluid pressure changes can destabilize faults, leading to earthquakes, such as the damaging magnitude-5.8 event in Pawnee, Oklahoma, in September 2016.

Among the more vexing scientific questions about injection-induced earthquakes is why they seem to be getting deeper in such places as Oklahoma and Kansas, where injection rates have been declining due to a combination of earthquake mitigation measures and declining oil and gas production.

In a study published Aug. 5 in Energy & Environmental Science, Ryan M. Pollyea, assistant professor in the Department of Geosciences, and a team of student researchers proposed a new theory that the wastewater itself plays an important role in the processes that cause injection-induced earthquakes.

"We know that earthquakes are getting deeper in Oklahoma," said Pollyea, who directs the Computational Geofluids Lab at Virginia Tech, "so we're trying to figure out what conditions make this possible. Our research suggests that it's caused by combination of the geology, natural fluids in the basement rocks, and the wastewater itself."

Although researchers have known for decades that deep fluid injections can trigger earthquakes, Pollyea said previous research misses some consequential details about how they occur. Specifically, he pointed out that oilfield brine has much different properties, like density and viscosity, than pure water, and these differences affect the processes that cause fluid pressure to trigger earthquakes.

"The basic idea is that oilfield brine has a lot of dissolved solid material, which makes the wastewater heavier than naturally occurring fluids in deep geologic formations," said Richard S. Jayne, a co-author of the study and former Ph.D. student at Virginia Tech who is now a research hydrogeologist at Sandia National Laboratory, "so the dense wastewater sinks, increases fluid pressure, and causes deeper earthquakes than would be predicted if the fluids have the same material properties."

Using supercomputers at Virginia Tech's Advanced Research Computing division, Pollyea and his team tested their idea by producing more than 100 models of oilfield wastewater disposal using various combinations of geologic properties, wastewater temperature, and wastewater density. With this computational approach, the team isolated both the conditions and physical processes that alter fluid pressure in the geologic formations.

"We found that there are really two different processes that drive fluid pressure deep into the basement, where earthquakes occur," saids Pollyea. "The first is called pressure diffusion, which occurs when wastewater is forced into geologic formations that are already full of water. This process has been known for a long time, but the second process occurs when high-density wastewater sinks and pushes lower density fluids out of the way."

According to this new theory, the density difference between wastewater and deep basement fluids is much more important for induced earthquake occurrence than was previously known. "This is one of the areas that has been neglected in induced-seismicity research," said Megan Brown, an assistant professor of geology who specializes in fluid triggered seismicity at Northern Illinois University and was not involved in this study. "Density-driven pressure transients are an intuitive consequence of a density differential between injected fluids and formation fluids."

Although earthquake occurrence has been decreasing in the central U.S. since the peak years of 2014 and 2015, this new theory not only explains why earthquakes are getting deeper in Oklahoma, but it also explains why several magnitude-5+ earthquakes struck Oklahoma in 2016, when injection rates were decreasing state wide.

"One fascinating aspect of our study is that sinking wastewater plumes do not require pumping to migrate deeper underground," said Pollyea, "in fact, they'll continue sinking under their own weight for decades after injections cease, and our study shows that the wastewater doesn't have to be much heavier for this to occur."

In terms of earthquake mitigation and regulatory practices, this study has far-reaching implications: The research team pointed out that high-density brines occur throughout many oil and gas basins in the U.S. But they also argued that using this study in practice requires much more information about the fluids. "This study emphasizes the need for site-specific data and increased sampling," said Brown, because "density differences as a driving factor of near-field pressure transients may also lead to pre-injection mitigation actions."

Pollyea said that his research team is continuing to work on their new theory for the hydrogeologic processes that cause induced earthquakes. "We're really interested to know how our ideas about fluid chemistry affect regionally expansive injection operations in places like Oklahoma and Texas," said Pollyea. "And one of our recent M.S. graduates, Graydon Konzen (a study co-author), has done some exciting new work in this area."

Mobile phones have the power to change the lives of women living in remote communities by reducing barriers to information and increasing access to local economies. However, the introduction of new technologies can hamper efforts to empower women by increasing disparities in power dynamics.

Video:https://www.youtube.com/watch?time_continue=1&v=YOgYpR5cb5w&feature=emb_logo

Associate Professor Timothy Baird of the College of Natural Resources and Environment and Kelly Summers, who earned a master's degree in geography from Virginia Tech in 2019, led a National Science Foundation-funded study examining the impact that mobile phones are having in Maasai communities in Tanzania. Their findings, published in the Journal of Rural Studies, reveal crucial insights into the ways that technology impacts social dynamics in a distinct community in Africa.

A nomadic people adapt to a changing world

The Maasai are an ethnic group of approximately 2 million people, living primarily in Kenya and Tanzania. As one of a number of indigenous groups in Africa to practice pastoralism, which involves the rearing of livestock, the Maasai have traditionally been nomadic, traversing the continent's Great Rift Valley to find grazing land for their animals.

This way of life, which has sustained Maasai for centuries, is evolving rapidly with the widespread expansion of western society and the ideas and technologies that come with it.

"Maasai are moving into a world some might call 'modern,'" noted Baird, a faculty member in the Department of Geography who has been researching Maasai communities since 2005. "Already there are aspects of our own 'western' lives that are evident in their lives. For example, several developments in Maasai society, from the growth of formal education to the spread of organized religion, have led to changes in the traditional structures that shape Maasai lives. From my vantage, mobile phones have been a kind of steroid for accelerating those changes."

For a population that herds livestock across wide stretches of wild savanna, mobile phones are a boon to their economy and life. But few studies have investigated how this new technology is impacting the lives of women in Maasai communities, which are traditionally patriarchal. In family units where men exert significant control, often over multiple wives, it is important to understand how phones have impacted gender dynamics.

"As a man, it's difficult -- and really not appropriate -- for me to have meetings with individual women or groups of women," Baird explained. "Maasai men may be quite uncomfortable with such a setup, and Maasai women may have no experience engaging with a man who is not a relative. So I needed help."

Enter Kelly Summers, who received bachelor's degrees in natural resources conservation and in forestry from Virginia Tech in 2014.

"While I was serving as an agriculture Extension agent with the Peace Corps in Tanzania, I read an article about Tim's research and reached out to him about doing graduate work in Tanzania," said Summers, who is currently working as an environmental protection specialist for the U.S. Environmental Protection Agency. "Because I had experience interacting with women while living in and traveling to remote communities in Tanzania, it was a good fit."

Summers, working with collaborators, including Maria Elisa Christie, director of women and gender in international development for Virginia Tech's Center for International Research, Education, and Development, was able to conduct interviews with Maasai women, trying to puzzle out the difficult question of what women's empowerment might look like in a cultural context bounded by traditions but also stimulated by an expanding world.

"I don't want to paint a monolithic picture of a whole group of people," Summers said. "All of the women I spoke with had multiple identities within their communities: some women owned businesses, and some took on the work of tending to livestock. They were mothers and wives. Some were teachers and some were active in churches. There are a range of identities, and phones impact those identities for better or worse, or both."

Understanding the contexts of empowerment

To understand how a new technology like mobile phones could potentially support women's empowerment, it was important for researchers to understand what empowerment would look like within the specific contexts of Maasai life.

"To unpack this idea of empowerment, we had to characterize our terms and then look for examples of those characterizations," Baird said. "We had to ask: what are the aspects of your social world, what are the physical materials, and what are your own personal assets that allow you to make decisions and then act on those decisions. From that, we could develop more targeted questions about issues that embody empowerment and the factors that promote or obstruct it."

For Maasai women, the barriers to using mobile phones to gain empowerment vary: from access to reliable electricity to technological fluency and literacy, to having the financial resources to pay for data, their ability to use phones is shaped by a broad array of issues that are themselves in a state of radical flux. The study results show that some concerns are unique to Maasai communities, while others seem universal.

"One observation we made was that Maasai women are very much addicted to their phones," Summers explained. "If they can't get a charge or they can't purchase minutes, the feeling they have is very similar to our own anxiety when our phones lose power. We all want to communicate, we all want to be in a community, and phones are becoming a major tool to do that among Maasai women. Those who don't have access to a phone very much feel that they're missing out."

To work around some of the challenges pertaining to access, Maasai women have found cooperative solutions. Baird and Summers cite the important role that informal village community banks play in allowing women to develop business relationships with other women outside their family units, increasing the women's economic autonomy.

While mobile phones are a positive motivator in seeking these burgeoning opportunities, the authors stressed that mobile phones can also reinforce inequalities. For Maasai women, who typically have multiple roles within family and community structures, mobile phones can simultaneously empower an individual in one role while disempowering her in another.

"The same power dynamics that already existed are now playing out with phones," Baird said. "We found that men, the traditional gatekeepers in this society, are the ones who often control women's phones. They can use them as a reward or a punishment, a carrot or a stick."

Summers added that one of their findings is that Maasai men and women used phones differently: "Men will use their phones to talk to people outside their immediate social circle, but women will primarily talk to people they already know: mothers and sisters and other people in their family unit. They are rarely using their phones to reach out to new people."

While mobile phones can be used in ways that empower women, the researchers stress that it is more realistic to view this technology as a new arena where tensions between traditional cultural norms and the growing aspirations to engage in a broadly interconnected world continue to play out. Future efforts aimed at using mobile technologies to advance women's empowerment need to better understand what empowerment would look like within the specific contexts of a distinct culture, and what consequences -- positive and negative -- are risked when new technologies take root.

The past few months have been a highly unusual time as people sheltered in place to prevent the spread of COVID-19. Schools, streets and stadiums fell silent, tourist hot spots became ghost towns, and sidewalk traffic largely consisted of grocery and food deliveries.

In an article published this week in Cities & Health, UBC planning experts Jordi Honey-Rosés and Erick Villagomez analyzed the implications of these changes on city planning and space design. Alongside other scholars from Chile, China, Mexico, India and Spain, they looked at the measures taken by major cities to cope with the pandemic, and how those efforts transformed and continue to transform urban life.

The researchers say the pandemic is transforming city building, design, energy flows, mobility patterns, housing preferences, green spaces and transportation systems. Many of these changes may be temporary, while others may be permanent.

"In some cases, cities are accelerating the implementation of changes they had in the works already, such as rolling out planned bicycle infrastructure, street calming projects or sidewalk re-designs. In other cases, planners and neighbours are making things up as they go along, experimenting, testing and relying on low-cost interventions," said Honey-Rosés, an associate professor in the School of Community and Regional Planning at UBC.

Erick Villagomez, a part-time lecturer at the school, noted the drop in pedestrian traffic associated with commercial activity during COVID-19. According to the most recent Google Mobility Report, mobility associated with retail and recreation across Canada still sits at about 17 per cent below January-February median levels.

"Although this rate continues to rise slowly, the reduced pedestrian traffic to-date has already had strong effects on many local businesses, many of which have had to close their doors indefinitely. This trend will likely continue until a viable solution to the pandemic is found," said Villagomez.

Over the longer term, the researchers see further changes taking place, with cities likely looking to implement low-cost and temporary street calming and pedestrianization projects. "Streets might need to be re-designed. With online shopping and home food delivery having taken off, there is huge demand for curbside street parking, not only to meet new delivery needs, but also to free space for pedestrians," said Honey-Rosés.

They add that the look and feel of cities that rely on tourism will change, both in negative and positive ways. Businesses may continue to struggle, but there is an increased interest in building a stronger pedestrian-friendly environment. In Toronto, for example, the City accelerated plans to install cycling infrastructure along the popular Danforth Avenue as a part of COVID-19 relief plans.

As well, there is now a greater appreciation of the importance of providing easily accessible opportunities for the enjoyment of nature and a diversity of recreation activities. Cities may revisit the potential of unused spaces such as brownfield sites and building rooftops, citing the staggering amount of rooftops that are underused in many cities and could be converted into rooftop gardens.

Over time, the researchers say our sense of place and space may be permanently transformed. "Public space might still be a place for social interaction, but it may be more difficult for the spontaneous and informal. The pandemic may limit our ability to develop new relationships, especially among strangers," said Honey-Rosés.

On the positive side, the pandemic has given us an unprecedented opportunity to examine the links between urban planning, public space and wellbeing, he added. "Our future city is not preordained, but will be the result of specific decisions about public space. We hope citizens will talk to their leaders and come together with planning and policy professionals to build healthier cities during this crisis and beyond."

Villagomez, who has written extensively about the implications of transforming cities to meet the standard six-foot social distancing protocols, notes that the everyday spaces we inhabit have been shaped by millennia based on dimensions that are much smaller--three to four feet being the most common.

"Right now, people are attempting to adapt systems, behaviours and built spaces based on three-to-four-foot distances to the larger social-distancing dimensions. The results have been very interesting, showing a lot of creativity and innovation. But it's also already evident that cities cannot and will not fully change in every respect to allow six-foot distancing. This will continue to evolve as restrictions change," Villagomez added.

New Orleans, LA -- Research led by Nicolas Bazan, MD, PhD, Boyd Professor and Director of the Neuroscience Center of Excellence at LSU Health New Orleans School of Medicine, and Ludmila Belayev, MD, LSU Health New Orleans Professor of Neuroscience, Neurology and Neurosurgery, has unlocked a key fundamental mechanism in the communication between brain cells when confronted with stroke. They report that DHA not only protected neuronal cells and promoted their survival, but also helped maintain their integrity and stability. The discovery provides potential new clinical targets and specific molecules for the treatment of ischemic stroke and other cardiovascular diseases. Their findings are published online in CNS Neuroscience & Therapeutics, available here.

Brain cells talk to one another. This synchronized cell-to-cell crosstalk regulates neuroinflammation and the immune system, which are activated in the brain at the onset of stroke, Alzheimer's, Parkinson's, and other diseases. The researchers found that in the model of stroke, docosahexaenoic acid (DHA) affects the levels of two proteins crucial to communication between brain cells -- mesencephalic astrocyte-derived neurotrophic factor (MANF) and triggering receptor expressed on myeloid cells-2 (TREM2). They discovered that treatment with DHA reduced the size of the damaged brain area, initiated repair mechanisms and greatly improved neurological and behavioral recovery. These findings provide a major conceptual advance of broad relevance for neuronal cell survival, brain function and, particularly, stroke and neurodegenerative diseases.

DHA is made from omega-3 very long chain polyunsaturated fatty acids (VLC-PUFAs,n-3). It is found in fatty, cold-water fish like salmon. Among other benefits, DHA is essential for normal brain function in adults and for the growth and development of the brain in babies.

"Our findings contribute greatly to our understanding of cellular interactions engaging neurons, astrocytes, and microglia to sustain synaptic circuitry, set neurogenesis in motion, and initiate restoration to pathological derangements," notes Dr. Bazan, who also holds the Ernest C. and Ivette C. Villere Chair at LSU Health New Orleans.

These findings advance the understanding of how the complexity and resiliency of the human brain is sustained, mainly when confronted with adversities as in stroke. A key factor is how neurons communicate among themselves. These novel molecules participate in delivering messages to the overall synaptic organization to ensure the accurate flow of information through neuronal circuits.

"We know how neurons make synaptic connections with other neurons; however, these connections have to be malleable in order to change to the appropriate strength through experience," explains Dr. Belayev.

"It's like an orchestra," says Bazan. "You need a conductor, and this is the role that DHA plays. Such a large-scale complexity first requires violinists, or in this case, synapses, which are highly sensitive sites of stroke injury that become messengers to target vulnerable cells."

How a valveless embryonic heart tube pumps blood is a long-standing scientific mystery. Thanks to innovations in light-based technology, fresh insights are now available into the biomechanics of mammalian cardiogenesis—and in particular, the pumping dynamics of the mammalian tubular embryonic heart.

4D OCT (3D + time)

Shang Wang of the Stevens Institute of Technology and Irina Larina of the Baylor College of Medicine used cutting-edge 4D optical coherence tomography (OCT) to study the pumping mechanism underlying the developing mammalian heart for the first time. Their report, published in the peer-reviewed open access Journal of Biomedical Optics, demonstrates that 4D OCT imaging of mouse embryonic heart can provide unprecedented information about how the early mammalian heart works.

The study demonstrates the richness of data provided by this approach and its feasibility for investigating the functional relation between blood flow and heart wall dynamics within different regions of the embryonic mammalian heart—a possibility not currently accessible by other methods. The approach can be potentially used to assess cardiac pumping over embryonic development as the heart tube remodels, which could reveal functional changes during early cardiogenesis.

Biomechanics of the tiny mouse heart

The unique imaging scales and dynamic contrasts offered by OCT enable millimeter-level imaging depth with a microscale resolution that is ideal for capturing the entire mouse heart at mid-gestation stages. OCT also provides a clear view of fine cardiac structures as well as blood flow. The high imaging speed of OCT together with post-acquisition synchronization allows reconstructing the fast dynamics of the beating heart.

Amy L. Oldenburg, director of the Optical Coherence Imaging Laboratory at University of North Carolina at Chapel Hill, remarked, "The innovative method offers a new way of studying developmental cardiac biomechanics. Analysis of the 4D OCT images allowed Wang and Larina to relate blood flow, flow resistance, and pressure gradients induced by heart wall movements."

There is much to be learned. Although the mechanism that pumps blood within the embryonic heart tube has traditionally been thought to be wavelike peristaltic contractions, Wang and Larina were able to offer a more detailed assessment using 4D OCT to integrate cardiodynamics and hemodynamics. Their pilot observations suggest that localized heart tube pumping in the ventricles functions through a combination of suction and pushing mechanisms.

Increasing understanding of congenital heart defects

Biomechanical factors are increasingly recognized for their essential roles in stimulating and regulating the heart development. The authors hope that their approach may inspire new ideas and innovative designs in imaging and measurement techniques to assess the embryonic cardiac biomechanics. In particular, the method may provide useful ways to better understand the mechanisms contributing to congenital heart defects, which are abnormal formations of the heart that develop before birth. According to Oldenburg, the results of this study "showcase the utility of these methods for studying biomechanical changes in mutant embryonic hearts that model congenital heart defects." As mutant mouse lines modeling congenital heart defects are widely available, the method may contribute to increased understanding of the earliest development of the most common form of birth defect in humans.

Read the original open access report: "Live mechanistic assessment of localized cardiac pumping in mammalian tubular embryonic heart," J. of Biomedical Optics, 25(8), 086001 (2020), doi 10.1117/1.JBO.25.8.086001

DOI

10.1117/1.JBO.25.8.086001

ORLANDO, August 6, 2020 - University of Central Florida researchers have developed a new type of laser beam that doesn't follow long-held principles about how light refracts and travels.

The findings, which were published recently in Nature Photonics, could have huge implications for optical communication and laser technologies.

"This new class of laser beams has unique properties that are not shared by common laser beams," says Ayman Abouraddy, a professor in UCF's College of Optics and Photonics and the study's principal investigator.

The beams, known as spacetime wave packets, follow different rules when they refract, that is when they pass through different materials. Normally, light slows down when it travels into a denser material.

"In contrast, spacetime wave packets can be arranged to behave in the usual manner, to not change speed at all, or even to anomalously speed up in denser materials," Abouraddy says. "As such, these pulses of light can arrive at different points in space at the same time."

"Think about how a spoon inside a water-filled glass looks broken at the point where the water and air meet," Abouraddy says. "The speed of light in air is different from the speed of light in water. And so, the light rays wind up bending after they cross the surface between air to water, and so apparently the spoon looks bent. This is a well-known phenomenon described by Snell's Law."

Although Snell's Law still applies, the underlying change in velocity of the pulses is no longer applicable for the new laser beams, Abouraddy says. These abilities are counter to Fermat's Principle that says light always travels such that it takes the shortest path, he says.

"What we find here, though, is no matter how different the materials are that light passes through, there always exists one of our spacetime wave packets that could cross the interface of the two materials without changing its velocity," Abouraddy says. "So, no matter what the properties of the medium are, it will go across the interface and continue as if it's not there."

For communication, this means the speed of a message traveling in these packets is no longer affected by traveling through different materials of different densities.

"If you think of a plane trying to communicate with two submarines at the same depth but one is far away and the other one's close by, the one that's farther away will incur a longer delay than the one that's close by," Abouraddy says. "We find that we can arrange for our pulses to propagate such that they arrive at the two submarines at the same time. In fact, now the person sending the pulse doesn't even need to know where the submarine is, as long as they are at the same depth. All those submarines will receive the pulse at the same time so you can blindly synchronize them without knowing where they are."

Abouraddy's research team created the spacetime wave packets by using a device known as a spatial light modulator to reorganize the energy of a pulse of light so that its properties in space and time are no longer separate. This allows them to control the "group velocity" of the pulse of light, which is roughly the speed at which the peak of the pulse travels.

Previous work has shown the team's ability to control the group velocity of the spacetime wave packets, including in optical materials. The current study built upon that work by finding they could also control the spacetime wave packets' speed through different media. This does not contradict special relativity in any way, because it applies to the propagation of the pulse peak rather than to the underlying oscillations of the light wave.

"This new field that we're developing is a new concept for light beams," Abouraddy says. "As a result, everything we look into using these beams reveals new behavior. All the behavior we know about light really takes tacitly an underlying presumption that its properties in space and time are separable. So, all we know in optics is based on that. It's a built-in assumption. It's taken to be the natural state of affairs. But now, breaking that underlying assumption, we're starting to see new behavior all over the place."

Co-authors of the study were Basanta Bhaduri, lead author and a former research scientist with UCF's College of Optics and Photonics, now with Bruker Nano Surfaces in California, and Murat Yessenov, a doctoral candidate in the college.

Bhaduri became interested in Abouraddy's research after reading about it in journals, such as Optics Express and Nature Photonics, and joined the professor's research team in 2018. For the study, he helped develop the concept and designed the experiments, as well as carried out measurements and analyzed data.

He says the study results are important in many ways, including the new research avenues it opens.

"Space-time refraction defies our expectations derived from Fermat's principle and offers new opportunities for molding the flow of light and other wave phenomena," Bhaduri says.

Yessenov's roles included data analysis, derivations and simulations. He says he became interested in the work by wanting to explore more about entanglement, which in quantum systems is when two well-separated objects still have a relation to each other.

"We believe that spacetime wave packets have more to offer and many more interesting effects can be unveiled using them," Yessenov says.

Abouraddy says next steps for the research include studying the interaction of these new laser beams with devices such as laser cavities and optical fibers, in addition to applying these new insights to matter rather than to light waves.

As more states in the U.S. push for increased reliance on variable renewable energy in the form of wind or solar power, long-term energy storage may play an important role in assuring reliability and reducing electricity costs, according to a new paper published by Caltech researchers.

Graduate student Jackie Dowling, who works in the lab of Nathan Lewis (BS '77), the George L. Argyros Professor and professor of chemistry, has collaborated with Ken Caldeira at the Carnegie Institution for Science and others to examine energy-storage options and multiple decades of data about wind and solar availability. Dowling and her collaborators determined that currently available battery technology is prohibitively expensive for long-term energy storage services for the power grid and that alternative technologies that can store a few weeks' to a month's worth of energy for entire seasons or even multiple years may be the key to building affordable, reliable renewable electricity systems.

Energy storage is needed with renewable energy because wind and solar energy are not as reliably available as fossil fuels. For example, wind power is often at its lowest during the summer in the United States, which is when the electrical grid is strained the most by the demand for air conditioning in homes and businesses.

"This research is motivated by the fact that laws in several states have mandated 100 percent carbon-free electricity systems by midcentury," says Dowling, lead author of a paper about the work. "Within these mandates, a lot of states include requirements for wind and solar power. Both wind and solar are variable from day to day, or even year to year, yet high reliability is mandatory for a viable electricity system. Energy storage can fill in for the gaps between supply and demand."

Dowling looked at short-duration storage systems, such as lithium-ion batteries, and long-duration storage methods, such as hydrogen storage, compressed-air storage, and pumped-storage hydroelectricity.

To see how to optimize the use of those storage technologies at the lowest energy cost, Dowling built a mathematical simulation of each and incorporated historical electricity-demand data and four decades of hourly resolved historical weather data across the contiguous U.S. The Macro Energy Model, as she calls it, reveals that adding long-duration storage to a wind-solar-battery system lowers energy costs. In contrast, using batteries alone for storage makes renewable energy more expensive.

Dowling says that the extra expense associated with batteries occurs because they cannot cost-effectively store enough energy for an entire season during which electricity is generated in lower amounts. That means an electrical grid would require many costlier solar panels or wind turbines to compensate and would result in wasteful idling of electricity-generation equipment for much of the year.

Currently available battery technology is not even close to being cost effective for seasonal storage, Dowling says.

"The huge dip in wind power in the summer in the U.S. is problematic, and batteries are not suitable for filling that gap. So, if you only have batteries, you have to overbuild wind or solar capacity," she says. "Long-duration storage helps avoid the need to overbuild power generation infrastructure and provides electricity when people need it rather than only when nature provides it. At current technology costs, storage in underground caverns of green hydrogen generated by water electrolysis would provide a cost-effective approach for long-duration grid storage."

Other researchers have built renewable energy models, but the team's data-driven approach is the first to incorporate four decades of historical wind and solar variability data, thus factoring in variability from year to year and periodic episodes of rare weather events that affect power generation, such as wind and solar droughts.

"The more years of data we use in our models, the more we find a compelling need for long-term storage to get the reliability that we expect from an electricity system," she says.

Dowling suggests her findings may be helpful to policy makers in states with 100 percent carbon-free electricity laws and high wind/solar mandates and to other U.S. states considering the adoption of similar laws. In the future, she plans to extend her research to take an in-depth look at the roles that specific types of energy storage, such as hydrogen or redox flow batteries, can play in renewable energy systems. For instance, some types of batteries might effectively serve as medium-duration energy storage, she says.

The barrier islands of North Carolina's Cape Hatteras National Seashore are among the most popular recreational destinations on the Atlantic coast. Park managers strive to integrate the needs of wildlife with recreational use of the area's beaches, but in some cases, they impose restrictions on the latter in order to preserve the former--sometimes even completely closing portions of beaches to pedestrian and off-road vehicle traffic to protect nesting birds. These closures are controversial, but a new independent report from the American Ornithological Society (AOS) finds evidence that despite complaints from the public, they provide significant benefits for vulnerable beach-nesting birds and sea turtles.

Two such beach-nesting birds--the American Oystercatcher and federally threatened Piping Plover--are of particular concern to Park managers. Populations of both species at Cape Hatteras declined in the late 1990s and early 2000s. The plover population recovered to pre-decline levels, whereas the oystercatcher population did not. In 2016, in response to the ongoing controversy over beach closures in the park, the National Park Service asked AOS to assemble an expert panel and produce an independent report assessing the appropriateness of the current NPS beach management plan.

Two factors that determine whether a population of shorebirds grows are carrying capacity (how many individuals the existing habitat can support) and productivity (how many young are produced). According to the report, carrying capacity for the two shorebird species has been reduced due to disruption of barrier island dynamics by human structures and activities, but the National Park Service has limited options for boosting carrying capacity. However, Park managers do have options for increasing productivity.

Productivity is influenced by factors including predation and human disturbance, both of which have contributed to past shorebird declines. The presence of humans can indirectly increase the risk to birds from predators such as raccoons, which are initially attracted to human trash and then stick around to raid nests. Wildlife managers might be able to boost productivity by removing more predators from the local ecosystem, but that doesn't mean that beach closures can be scrapped in favor of increased predator control. The report also found that the controversial beach closures, though not sufficient on their own to increase productivity enough for populations to grow, appear to be necessary for maintaining productivity at its current level.

"Overall, we found the Park's management of beach-nesting species, which include sea turtles and colonial terns and skimmers as well as the two shorebirds, to be appropriate, although some Park objectives should be reevaluated in light of recent research," says Jeff Walters, lead author of the report. "There is ample evidence of the benefits of restrictions on pedestrian and off-road vehicle activity to protect beach-nesting species, although this is just one of several factors important to the success of these species at Cape Hatteras National Seashore."

The full report by J.R. Walters, A.A. Dayer, S.J. Dinsmore, M.H. Godfrey, C.L. Gratto-Trevor, E. Nol, S.R. Riggs, which was prepared by The American Ornithological Society Committee on Science Arbitration, can be found here: https://americanornithology.org/wp-content/uploads/2020/08/CAHA-report_final-AOS.pdf

WSU Everett faculty members from the Edward R. Murrow College of Communication, the Voiland College of Engineering & Architecture and the Carson College of Business observed that several industries challenge Science, Technology, Engineering, and Math (STEM) education to incorporate business and communication experiences to prepare students for the workplace. These recommendations encouraged WSU Everett faculty to design this experiential learning project for students, as highlighted in their research, "STEM-Oriented Alliance for Research (SOAR) An educational model for interdisciplinary project-based learning." The study was presented at the 127th ASEE Annual Conference in June.

"We don't want our students just to keep up, we want them to lead," said Lucrezia Paxson, co-author of the study and a career track (scholarly) assistant professor at WSU Everett's Murrow College. "Project-based interdisciplinary learning builds student confidence, good communication and group cohesion."

The interdisciplinary teams of communication, electrical engineering, and business students worked to find solutions to real industry challenges by collaborating with their multidisciplinary team for real-life clients, including Boeing and Fluke. Electrical engineering students designed product prototypes, business students produced marketing plans and sales pitches for the products, and communication students created videos and infographics for the final presentations to clients.

Teams participated in a semester-long project that combined instructor meet-up sessions, group projects outside of class, and individual assignments. Projects culminated in a presentation of a final product pitch to clients from the perspectives of engineering, communications and marketing.

"This initiative has been hard work for all involved. However, the cross-discipline learning and the intellectual dexterity it fosters in our students has been worth it," Paxson said.

The WSU Everett team hopes that these project-based learning projects create cohesion among disciplines and give students the skills to be successful in professional settings. Their research also highlights both the challenges and benefits of working to bring real-world models into the classroom.

Researchers at the University of Michigan are interested in changing the behavior of some 2 million farm youths affected by hazardous noise exposure and hearing loss in the United States.

A study by the U-M School of Nursing found that incorporating hearing health education into an existing safety program increased the knowledge and attitude of hearing conservation practices among farm youths. It suggests that revisiting in-person lessons with online "boosters" or re-cap lessons may provide a pathway for sustainable hearing protection behaviors.

The research followed nearly 2,000 fourth graders from farm and rural communities, splitting them into groups to determine the effectiveness of various hearing health education programs. They were split into roughly three even groups: one group took part in a Safety Day hosted by the Progressive Agriculture Foundation; another group participated in that same program but also received a follow-up online booster; and the third group had no planned hearing health education lesson.

In comparison to the group without the lesson, those who had received the in-person lesson and the booster showed significant increases in favorable knowledge and attitudes toward hearing conservation practices.

While the content of the lessons were designed by Marjorie McCullagh, U-M professor of nursing, and her team, the actual instructors were community volunteers.

"The volunteers were almost exclusively untrained in education and health care, but they were committed to the idea that farm safety for kids is important," she said.

When volunteers submitted their 20-minute lessons for review, McCullagh said the team was impressed by the skill in using best practices for educating children.

"The instructors jumped in and learned the curriculum and did a fantastic job," she said.

The lesson developed and tested by McCullagh's research team has been adopted by the Progressive Agriculture Foundation for inclusion in its curriculum--delivered to more than 100,000 farm children and adults annually.

The study also revealed how frequently farm youth are exposed to hazardous noises. Nearly 10% of participants reported hearing loud sounds that "made your ears hurt or made you hear ringing sounds," and 85%, 63% and 43% reported exposure to one, two, and three sources of hazardous noise, respectively, at least once per week.

McCullagh said such noise exposure is unfortunately considered normal. Farm children usually start operating tractors by age 7 or 8. Even infants may be given tractor rides while still in their carriers.

Children from farm and rural communities are also more likely to be exposed to bystander noise, such as a running tractor used to power other machinery. While an adult farm worker might wear hearing protection when operating the tractor, children playing around the farm and exposed to the noise most likely do not.

In one of the study's exercises, students held a handful of chenille stems that represented hairlike cells inside the inner ear. The students then imagined a typical day, and, for encounters with progressively louder noises (talking with parents, using the lawn mower, a July 4 fireworks show), the students would run their hands over the chenille stems with increasing vigor. When asked to straighten the stems back to their original state, the students realized they couldn't.

The message was clear: Hearing damage cannot be undone.

While the study provides evidence for improvement in knowledge and attitudes toward hearing conservation and noise mitigation strategies, there was no significant evidence that the online booster affected participants' actual intent to use such strategies.

Possible limitations included measuring by self-report and potential confounding due to the "measurement effect," wherein repeated testing (interviewing participants) might have served as its own intervention.

The finding isn't unfavorable, McCullagh says.

"There's not going to be a one-shot solution," she said. "We were successful in changing knowledge, attitudes and beliefs, which is encouraging because we know that those are precursors to changing behavior in the long term."

It's the long-term change in behavior that interests McCullagh. A native of North Dakota, she has witnessed first hand how farmers are at risk for many occupational hazards and underserved by health and safety programs.

Her next project will focus on determining the prevalence of farmer suicide. The issue is interconnected with hearing health, she says, since individuals with hearing loss often socially isolate and develop low self-esteem, which contributes to depression and anxiety.

McCullagh hopes her work with children can inspire the right habits to break such a vicious cycle.

"There is still so much to be done," she said.

Autonomous vehicles (AVs) will challenge cities in ways that are difficult to fully predict, and yet critical to address early. A particular challenge is the potential for AVs to upset municipal budgets, as they upend traditional auto-related funding streams like vehicle registration fees and parking revenues. To prepare for this uncertain future, cities should practice scenario planning to understand revenue implications and identify alternative solutions.

As a proxy for AVs, researchers often examine transportation network companies (TNCs) like Uber and Lyft, because in many ways they operate as AVs will. In a 2019 NITC Small Starts project, "How Will Autonomous Vehicles Change Local Government Budgeting and Finance?" Benjamin Clark of the University of Oregon (UO) examined Seattle's parking demand and revenue implications for several downtown neighborhoods. Building on that work, Clark and UO colleague Anne Brown took a deeper dive into how new transportation technologies affect on-street parking revenues. Expanding their analysis to the entire City of Seattle, they compared Uber trip data with built environment and parking data from the City. The goal was in part to learn what other localized factors, including TNCs, might explain changes in parking demand. They found that up to a certain point, more Uber trips meant more parking spaces occupied: each additional 1,000 Uber trips was associated with a 17.1 percent increase in parking occupancy.

Download the Final Report "What Makes Cents? How Uber Shapes Municipal On-Street Parking Revenue" at: https://nitc.trec.pdx.edu/research/project/1215

Yet findings reveal that the relationship between TNC trips and parking occupancy is not linear. The model predictions show that parking revenues will decline if or when TNC (or possibly AV) trips are about three times greater than the average number of daily trips taken in 2016.

WAIT...SO WHY IS PARKING MORE OCCUPIED?

Intuition might say that more people using Uber should mean less parking occupation. While some travelers may hail an Uber instead of driving, it's not a simple substitution. Rather than reshuffling a fixed number of travelers from personal cars into Ubers, the advent of TNCs means more people are traveling to and from popular destinations using a combination of modes. TNCs complement other modes and may enable more people to travel on preferred routes and at more convenient times. The data used in this study do not provide insight into which TNC trips substitute for driving, which carry people who previously traveled by other modes or at other times of the day, or which are new trips entirely. Additional research is needed to better understand the potential mode shift dynamics between driving, TNCs, and other modes.

POLICY OPTIONS FOR CITIES

The analysis presented in this report assumes no policy action by cities. The researchers discuss several possible courses of action in the final report.

Adjust parking policies by time/day

While cities are not in immediate danger of losing parking revenues due to TNCs, parking revenues may erode at high levels of TNCs or AV trip-making. However, TNCs are not the only factor. Parking occupancy and revenue also depend on the local built environment, time of day, number of parking spaces, and parking price. This finding affords a policy opportunity across land uses: Policymakers and planners can adjust parking prices or policies by the time of day, or day of the week, to achieve desired occupancies or outcomes.

Lower parking prices

A simple option would be to lower parking prices to reflect lower demand for parking. However, this approach could run counter to many cities' efforts to encourage car-alternative travel.

Reduce on-street supply

Instead of lowering prices, cities could maintain parking prices but reduce their on-street parking supply; repurposing on-street spaces for other uses such as parklets, loading spaces, or non-auto parking spaces. This action could produce ancillary benefits such as managing congestion through additional loading spaces, facilitating micromobility with additional non-auto parking spaces, or enhancing the streetscape and public outdoor space.

Find alternative sources of revenue

Many cities are already experimenting with alternative uses for parking spaces: Washington, D.C., recently completed an on-demand, curb-space reservation pilot for a variety of commercial uses including TNCs, food deliveries, and commercial deliveries. Boston, too, is experimenting with similar pilots with some success. In both cases, the city replaced traditional parking revenue with another source (loading zone reservations) while simultaneously addressing congestion issues.

Focus on mixed-use and commercial areas

Per-space parking revenues in Seattle were highest in commercial and mixed-use areas. This may indicate that cities should, in the longer run, focus policy efforts on commercial and mixed-use areas for more revenue opportunities since they are projected to have larger revenue shortfalls. Finding replacements for these revenues, such as the piloted projects in Washington, D.C. or Boston, could help offset projected revenue losses, but may not be a panacea.

WHAT ELSE DO WE NEED TO KNOW?

Parking demand will not disappear overnight. Nevertheless, cities should engage in scenario planning to understand revenue implications as people take more TNC trips--and eventually AV trips--in the coming years. Dynamic analyses are needed to assess how parking rates change in response to higher TNC use, and how those changes could affect revenue.

Today, the entire globe is broken up into tectonic plates that are shifting past each other, causing the continents to drift slowly but steadily. But this has not always been the case.

The earliest evidence for plate tectonic features which could have been localized does not signify when plate tectonics became a global phenomenon. So, when did plate tectonics go global?

A research team led by Dr. WAN Bo from the Institute of Geology and Geophysics (IGG) of the Chinese Academy of Sciences has revealed that plate tectonics went global 2 billion years ago. The study was published in Science Advances on August 5.

The Earth is 4.56 billion years old. Although geologists have argued for plate tectonics being operational as early as 4 billion years ago, this is the first study to provide global evidence.

Subduction, the pushing of one plate beneath another when two plates converge, is one of the telltale signs of plate tectonics. Usually dense ocean crust is pushed back into the deep Earth as continents ride high. But when two continents collide, something is gonna happen.

The best known continental collision on Earth today is the Himalayan Mountains: as India slams into Eurasia, the smaller continent of India is pushed beneath the megacontinent. Geologists can image this collision with seismology: waves from earthquakes show Eurasia ramping up on top of India.

The IGG researchers designed a seismological study to investigate the structure of ancient crust at one of the oldest and most stable region, Ordos. Now, it is mostly flat without any high mountains. However, they found essentially the same deep structure (Fig. 1). "Even though the dipping structure we found was identical to what we see in the Himalaya today, what we were looking at was 2 billion years old," said Dr. WAN.

On top of their evidence of ancient subduction in China, the researchers demonstrated that several continents with seismological studies showed similar dipping structures 2 billion years ago too.

"The authors do a very nice job of describing their results and placing them into a larger scale context," said Prof. Peter Cawood, an expert in ancient plate tectonics at Monash University who wasn't involved in the study.

Even though subduction may have occurred here or there on Earth early on, it was not until 2 billion years ago that we can say plate tectonics became a global network.

"It's like the invention of the world wide web," said co-author Dr. Ross Mitchell of IGG. "Even though the internet existed in some form or another for decades, it wasn't until the 1990s that the Information Age began." So it was with plate tectonics.

Seismic evidence of subduction from six continents at this age is interpreted as the oldest evidence of global plate tectonics. The continental connections identified can be linked in a plate network that resulted in the assembly of Nuna, likely Earth's first supercontinent (Fig. 2).

"Immediately following plate tectonics going global, Earth formed arguably its first supercontinent," said Dr. Mitchell. "This coincidence is too compelling to ignore."

A lizard-like creature whose ancestors once roamed the Earth with dinosaurs and today is known to live for longer than 100 years may hold clues to a host of questions about the past and the future.

In a study published Aug. 5 in Nature, an interdisciplinary, international team of researchers, in partnership with Māori tribe Ngātiwai, sequenced, assembled and analyzed the complete genome of the Sphenodon punctatus, or the tuatara, a rare reptile whose ancestors once roamed the earth with dinosaurs. It hasn't changed much in the 150 million to 250 million years since then.

"We found that the tuatara genome has accumulated far fewer DNA substitutions over time than other reptiles, and the molecular clock for tuataras ticked at a much slower speed than squamates, although faster than turtles and crocodiles, which are the real molecular slowpokes," said co-author Marc Tollis, an assistant professor in the School of Informatics, Computing, and Cyber Systems at Northern Arizona University. "This means in terms of the rate of molecular evolution, tuataras are kind of the Toyota Corolla--nothing special but very reliable and persistently ticking away over hundreds of millions of years."

Tuatara have been out on their own for a staggering amount of time, with prior estimates ranging from 150-250 million years, and with no close relatives the position of tuatara on tree of life has long been contentious. Some argue tuatara are more closely related to birds, crocodiles and turtles, while others say they stem from a common ancestor shared with lizards and snakes. This new research places tuatara firmly in the branch shared with lizards and snakes, but they appear to have split off and been on their own for about 250 million years--a massive length of time considering primates originated about 65 million years ago, and hominids, from which humans descend, originated approximately six million years ago.

"Proving the phylogenetic position of tuatara in a robust way is exciting, but we see the biggest discovery in this research as uncovering the genetic code and beginning to explore aspects of the biology that makes this species so unique, while also developing new information that will help us better conserve this taonga or special treasure," said lead author Neil Gemmell, a professor at the University of Otago.

One area of particular interest is to understand how tuataras, which can live to be more than 100 years old, achieve such longevity. Examining some of the genes implicated in protecting the body from the ravages of age found that tuatara have more of these genes than any other vertebrate species thus far examined, including humans. This could offer clues into how to increase humans' resistance to the ailments that kill humans.

But the genome, and the tuatara itself, has so many other unique features all on its own. For one, scientists have found tuatara fossils dating back 150 million years, and they look exactly the same as the animals today. The fossil story dates the tuatara lineage to the Triassic Period, when dinosaurs were just starting to roam the Earth.

"The tuatara genome is really a time machine that allows us to understand what the genetic conditions were for animals that were vying for world supremacy hundreds of millions of years ago," he said. "A genome sequence from an animal this ancient and divergent could give us a better idea about what the ancestral amniote genome might have looked like."

While modern birds are the descendants of dinosaurs, they are less suitable for this type of research because avian genomes have lost a significant amount of DNA since diverging from their dinosaur ancestors.

But the tuataras, which used to be spread throughout the world, have other unusual features. Particularly relevant to this research is the size of its genome; the genome of this little lizard has 5 billion bases of DNA, making it 67 percent larger than a human genome. Additionally, tuataras have temperature-based sex determination, which means the ratio of males to females in a clutch of eggs depends on the temperatures at which they are incubated. They also have a pronounced "third eye"--a light sensory organ that sticks through the top of their skulls. Mammals' skulls have completely covered the third eye, though they still contain the pineal gland underneath, which helps maintain circadian rhythms.

The tuatara also is unique in that it is sacred to the Māori people. This research, for all the scientific knowledge that came from it, was groundbreaking for its collaboration with the Indigenous New Zealanders. The purpose was to ensure the research aligned with and respected the importance of the tuatara in their culture, which has never been done before in genomic research.

"Tuatara are a taonga, and it's pleasing to see the results of this study have now been published," Ngātiwai Trust Board resource management unit manager Alyx Pivac said. "Our hope is that this is yet another piece of information that will help us understand tuatara and aid in the conservation of this special species. We want to extend a big mihi to all of those who have been involved in this important piece of work."

With the genome now sequenced, the international science community has a blueprint through which to examine the many unique features of tuatara biology, which will aid human
understanding of the evolution of the amniotes, a group that includes birds, reptiles and mammals.

The geometry of an object indicates its shape or the relationship of its parts to each other. Did you know that the electrons in solids also have geometric structures? In quantum mechanics, an electron in solids takes the form of a wave with periodicity so that the periodic electronic state, so-called the Bloch state, can be characterized by specifying its energy and crystal momentum which is proportional to its wave number. The relationship between the energy and the crystal momentum of electrons is called the band structure of solids. For electrons in solids, the Berry curvature and the quantum metric of Bloch states take the role of the curvature and the distance of an object in geometry.

In fact, the geometry of quantum states is one of the central concepts underlying diverse physical phenomena, ranging from the celebrated Aharonov-Bohm effect to the topological phases of matter developed more recently. For instance, the local Berry curvature is responsible for the anomalous Hall transport while its integral over a two-dimensional closed manifold gives the Chern number, an integer number describing the quantized Hall conductivity. However, compared to the physics of the Berry curvature, the effects of the quantum metric on physical phenomena are less understood, especially in solids, although there are several recent works proposing the physical observables related to the quantum metric. Especially, there has been no clear guideline for searching materials in which the physical properties related with the quantum metric can be observed.

Prof. YANG Bohm-Jung and Dr. RHIM Jun-Won at the Center for Correlated Electron Systems within the Institute for Basic Science (IBS) in Seoul National University, Seoul, South Korea, and Dr. KIM Kyoo at the Korea Atomic Energy Research Institute, Daejeon, South Korea, reported that they found a way to measure the quantum distance of Bloch states in solids by applying magnetic field. More specifically, the researchers have examined the energy spectrum under magnetic field, called the Landau level spectrum, of flat bands in the kagome and checkerboard lattices, and observed anomalous Landau level spreading arising from the flat band. Surprisingly, they found that the total energy spreading of the flat band's Landau level is solely determined by the maximum quantum distance between the Bloch states of the flat band. Namely, the quantum distance of the Bloch states in solid can be measured by applying magnetic field to two-dimensional materials with flat bands!

Recently, two-dimensional materials with flat bands have received a great attention as a new platform to realize intriguing electronic states. A flat band indicates an electronic band structure in which the energy does not change when crystal momentum is varied. Such intriguing flat band structures appear in various two-dimensional lattices including the kagome lattice, checkerboard lattice, etc. The theory group of the IBS CCES research team realized that, in many of the flat band systems, the Berry curvature of the Bloch states is zero due to the symmetry of the lattice. If the Berry curvature is strictly zero, one can naturally expect that the geometry of the Bloch states is solely determined by the quantum metric. This interesting aspect motivated the IBS theory team to seriously consider two-dimensional materials with flat bands as a promising playground to study physical properties related to the quantum metric.

In fact, the semiclassical quantization rule predicts that an ordinary parabolic band under magnetic field forms equally-spaced discrete Landau levels, and the energy difference between neighboring Landau levels is inversely proportional to the effective mass of the electrons. When applied to a flat band with an infinite effective mass, the semiclassical theory predicts zero Landau level spacing so that a flat band remains inert under magnetic field. In this study, the researchers observed a quite peculiar nature of the Landau level spectrum that is in sharp contrast to the conventional norm. They reported that the Landau levels of the flat bands spread into the empty region of the energy space where no electronic states are available in the absence of magnetic field.

The researchers found that the key to such an unusual Landau level spectrum is the fact that the flat band in the kagome and checkerboard lattices is crossing with another parabolic band at a point. The singularity in the wave function of the flat band arising from the band crossing point induces nontrivial geometric effect related to the quantum distance of the wave function, which in turn induces anomalous Landau level spectrum. The first author, Dr. RHIM Jun-Won states, "Understanding the role of the band crossing in flat bands was the key to describe the anomalous Landau levels. This finding provides a practical way to unambiguously extract the quantum distance in solids."

This study shows that the quantum distance or quantum metric can also play crucial roles in determining material properties as the Berry curvature does. Contrary to the previous works, this study clearly identified the candidate lattice systems in which the quantum metric effect is maximized while the Berry curvature effect is minimized, and discovered a way to directly extract the quantum distance in solids for the first time. Considering the tremendous impact of the concept of the Berry curvature on the understanding the properties of solids, it is natural to expect that this study may facilitate the future study about the geometric properties of solids related to the quantum metric and the search of materials in which the related physical responses can be observed.

Prof. YANG Bohm-Jung explains that "This result would provide a critical step towards the complete understanding of geometrical properties of quantum states in solids. As there are many two-dimensional lattice structures hosting flat bands, our study may trigger future research activities for discovering novel geometrical phenomena related to the quantum metric in various condensed matter materials."

Huntington disease is a progressive and aggressively debilitating brain disorder that causes uncontrolled movements, psychological problems, and loss of cognition. It is caused by a mutation in the gene that encodes the protein huntingtin, causing it to build an abnormally long tail of the amino acid glutamine. This tail prevents huntingtin from folding properly and as a result it aggregates inside neurons of the brain, and eventually kills them.

Huntington's affects hundreds of thousands of people in the world, and as an "autosomal dominant" disease, a person only needs one copy of the mutant huntingtin gene to develop the disease. Scientists in both academia and industry are exploring different approaches to tackle the disease. The most popular strategy is to lower the levels of huntingtin or to inhibit its aggregation - or a combination of both. The way to do this is to either "silence" the huntingtin gene or to activate cellular mechanisms that promote the degradation of the protein itself.

Now, scientists at the lab of Professor Hilal Lashuel at EPFL have identified a new enzyme that does both. The enzyme, called "TBK1", plays a central role in regulating the degradation and clearance of the huntingtin protein and introduces chemical modifications that block its aggregation. "We believe that this represents a viable target for the development of possible treatment of Huntington's disease," says Lashuel.

The TBK1 enzyme is a "kinase". In the cell, kinases are enzymes that add phosphate groups to various biomolecules like proteins or DNA. In the world of the cell, phosphate groups are energy-carriers, so adding one essentially "turns on" the receiving molecule.

Previous studies have shown that artificially adding phosphate groups to huntingtin can stop it from aggregating and causing Huntington's disease. "However, to explore the therapeutic potential of phosphorylation, we needed to identify the natural kinases that do the job inside the cell," says Lashuel. "After screening hundreds of kinases, we were excited to identify TBK1, because it did the job with high specificity and efficiency."

The researchers found that, when TBK1 adds a phosphate group anywhere in the first 17 amino acids of huntingtin, it inhibits its ability to aggregate. This was the case for both the normal and mutated versions of huntingtin.

In addition, increasing TBK1 levels in cells leads to over-phosphorylation of a specific amino acid (a serine) in the huntingtin chain. This stabilizes the protein and stops it from aggregating.

Finally, TBK1 was also found to signal the cell to degrade and clean out huntingtin before it aggregates. This lowers overall huntingtin levels, which results in reducing aggregate formation inside the cell.

Encouraged by their findings, the scientists then moved onto an animal model of Huntington's Disease: the worm C. elegans. What they found corroborated their previous data: Over-expressing the TBK1 kinase protected against mutant huntingtin toxicity in the worm, preventing the development of Huntington's Disease. The researchers got similar results in cultured neurons.

"Our work shows that TBK1-mediated increase in phosphorylation and/or promoting mutant huntingtin autophagic clearance represent viable therapeutic strategies for the treatment of Huntington's Disease," says Ramanath Hegde, who led the study.

"We are very excited about these findings," says Lashuel. "TBK1 has also been shown to regulate the clearance and degradation of proteins implicated in other neurodegenerative diseases. Mutations in TBK1 have also recently been linked to ALS and result in impaired autophagy, which leads to the accumulation of aggregates. Our goal is to find small molecules or drug pathways and to develop these for multiple neurodegenerative diseases."