Category: Science

Researchers have discovered a potential intranasal vaccine candidate that provides improved, longer-lasting immunity against SARS-CoV-2 viruses compared to when given as an injection.

In a new study, the researchers found that by triggering an immune response directly at the point of entry, the intranasal vaccine candidate enhanced long-term immune memory of the virus, which could translate to a reduced need for booster shots.

There is growing evidence that intranasal vaccines provide greater protection at mucosal surfaces, making this a vaccination route that could reduce breakthrough infections and subsequent transmission of the virus.

To delve into this, the researchers compared the immune responses from nasal and subcutaneous administration of the vaccine, as well as immunity from the vaccine with and without the use of adjuvants—substances added to vaccines to enhance the body’s immune response.

Published in eBioMedicine, the findings showed nasal administration of the vaccine candidate boosted mucosal antibody response, as expected. Additionally, and more importantly, it enhanced longer-lasting mucosal and systemic immune protection through preferential induction of airway-resident T cells and central memory T cells.

“Our data show that, compared to subcutaneous vaccination, the intranasal route improved the response of certain immune cells, known as T cells, which reduced disease severity,” says lead author Ashley St John, associate professor in the emerging infectious diseases program at Duke-NUS.

“Not only that, but it also resulted in a greater number of T central memory cells compared to subcutaneous vaccination, which could lead to longer-lasting protection.”

T central memory cells play a vital role in safeguarding the body upon re-exposure to a virus. They enhance the immune system’s memory, inducing long-lasting protective immune responses. This ability to retain this long-term memory of the virus suggests less need for a pathogen challenge to achieve the same level of protection against the virus, potentially translating into fewer boosters.

The research team also found that the use of adjuvants in the vaccine to promote immune response influenced the characteristics of T cells, as well as their activation and production of cytokines—tiny proteins that regulate cell communication and control inflammation—with different adjuvants leading to different T-cell responses.

Another notable finding from the study was that a type of antibody, called IgG, that circulates widely in the bloodstream is more effective at neutralizing variants of the virus, including newly emergent ones, when induced through the nasal vaccine route. These discoveries provide important scientific evidence that improved immunity responses from both T cells and IgG antibodies contribute to greater and long-lasting protection of intranasal vaccines from COVID-19.

“While the acute phase of the pandemic may be behind us, the rise of new variants, including JN.1, which has triggered an increase in hospital admissions locally, demonstrates that we have room in our arsenal of vaccines and treatments for even better tools. This study shows that mucosal vaccination holds promise for improving COVID-19 vaccine efficacy with potentially fewer boosters needed,” says Professor Patrick Tan, senior vice-dean for research.

The researchers have filed a patent on the discovery which covers the invention of the vaccine composition formulated for mucosal delivery, paving the way for an industry partnership to potentially develop mucosal vaccines against COVID-19 and other pathogens that also target mucosal surfaces.

Source: Duke-NUS

During the pandemic, cash assistance provided low-income mothers with greater flexibility to feed their families than food distributions, researchers report.

For the new study, the researchers interviewed 45 Black low-income mothers of young children in an underserved Houston neighborhood from April 2020 to June 2021, comparing two aid programs—Pandemic Electronic Benefits Transfer (P-EBT) cash assistance and in-kind food distributions.

They found that food distributions actually presented new challenges for families already shouldering heavy burdens. Mothers in need of food preferred cash assistance as it allowed them more flexibility in getting what they needed to feed their families.

Respondents mentioned a variety of reasons that food distributions were less desirable. One of the common ones mothers cited were long lines waiting for food, made worse when temperatures reached 100 degrees or higher. Respondents also said that food banks didn’t always have desirable food options and were difficult to access without a car.

As a result, traveling to and from distributions resulted in wasted transportation funds and/or time off work to procure food their families didn’t like or couldn’t eat.

In contrast, P-EBT funds allowed mothers to tailor their food choices to their specific households, while giving them flexibility with when and where they shopped. The researchers note that mothers expressed enthusiasm for the simple practicality of this system. Unlike food distributions, no mothers reported accessibility issues with the P-EBT program.

“Families know their own needs best. We need to recognize and trust their expertise instead of introducing additional tasks and complications,” says Simon Fern, a sociology doctoral student at Rice University and co-lead author of the study published in the American Journal of Public Health.

“Research consistently demonstrates that food insecurity emerges not from families’ shortcomings but deeply rooted societal issues. We need to continue to boost what we know works—direct and unconditional cash transfers to the most impacted communities.”

The researchers say they hope this study demonstrates how food assistance interventions, especially in emergency food situations such as pandemics or natural disasters, can be more successful and equitable by considering the needs and preferences of individuals using the programs.

“The work that food banks like our excellent Houston Food Bank do is crucial for communities,” says co-lead author Rachel Kimbro, chair in social sciences.

“However, during emergency situations, in addition to food distributions, low-income families may prefer to receive direct cash benefits to their existing SNAP or to EBT cards. It’s important to listen to the voices of those who are most vulnerable to and most impacted by these events.”

Additional coauthors are from North Carolina State University and Colorado College.

Source: Rice University

Researchers have developed a new soft robot design that engages in three simultaneous behaviors: rolling forward, spinning like a record, and following a path that orbits around a central point.

The device, which operates without human or computer control, holds promise for developing soft robotic technologies that can be used to navigate and map unknown environments.

The new soft robots are called twisted ringbots. They are made of ribbon-like liquid crystal elastomers that are twisted—like a rotini noodle—and then joined together at the end to form a loop that resembles a bracelet.

When the robots are placed on a surface that is at least 55 degrees Celsius (131 degrees Fahrenheit), which is hotter than the ambient air, the portion of the ribbon touching the surface contracts, while the portion of the ribbon exposed to the air does not. This induces a rolling motion; the warmer the surface, the faster the robot rolls.

“The ribbon rolls on its horizontal axis, giving the ring forward momentum,” says Jie Yin, corresponding author of a paper on the work and an associate professor of mechanical and aerospace engineering at North Carolina State University.

The twisted ringbot also spins along its central axis, like a record on a turntable. And as the twisted ringbot moves forward it travels in an orbital path around a central point, essentially moving in a large circle. However, if the twisted ringbot encounters a boundary—like the wall of a box—it will travel along the boundary.

“This behavior could be particularly useful for mapping unknown environments,” Yin says.

The twisted ringbots are examples of devices whose behavior is governed by physical intelligence, meaning their actions are determined by their structural design and the materials they are made of, rather than being directed by a computer or human intervention.

The researchers are able to fine-tune the behavior of the twisted ringbot by engineering the geometry of the device. For example, they can control the direction that the twisted ringbot spins by twisting the ribbon one way or the other. Speed can be influenced by varying the width of the ribbon, the number of twists in the ribbon, and so on.

In proof-of-concept testing, the researchers showed that the twisted ringbot was able to follow the contours of various confined spaces.

“Regardless of where the twisted ringbot is introduced to these spaces, it is able to make its way to a boundary and follow the boundary lines to map the space’s contours—whether it’s a square, a triangle, and so on,” says Fangjie Qi, first author of the paper and a PhD student. “It also identifies gaps or damage in the boundary.

“We were also able to map the boundaries of more complex spaces by introducing two twisted ringbots into the space, with each robot rotating in a different direction,” Qi says. “This causes them to take different paths along the boundary. And by comparing the paths of both twisted ringbots, we’re able to capture the contours of the more complex space.”

“In principle, no matter how complex a space is, you would be able to map it if you introduced enough of the twisted ringbots to map the whole picture, each one giving part of it,” says Yin. “And, given that these are relatively inexpensive to produce, that’s viable.

“Soft robotics is still a relatively new field,” Yin says. “Finding new ways to control the movement of soft robots in a repeatable, engineered way moves the field forward. And advancing our understanding of what is possible is exciting.”

The paper will appear in Proceedings of the National Academy of Sciences.

Support for the work came from the National Science Foundation.

Source: NC State

The long-term solution to elephant survival requires not only that areas are protected but are also connected to allow populations to stabilize naturally, a new study suggests.

Conservation measures have successfully stopped declines in the African savanna elephant population across southern Africa, but the new study shows the pattern varies locally.

For the study, published in the journal Science Advances, the researchers collected survey estimates and calculated growth rates for more than 100 elephant populations in southern Africa between 1995 and 2020, accounting for an estimated 70% of the global savanna elephant population.

“This is the most comprehensive analysis of growth rates for any large mammal population in the world,” says coauthor Rob Guldemond, director of the Conservation Ecological Research Unit (CERU) at the University of Pretoria, in South Africa.

Overall, the survey’s results are positive: There are the same number of elephants now as there were 25 years ago, a rare conservation win at a time when the planet is rapidly losing biodiversity.

However, the pattern is not consistent across regions. Some areas, such as south Tanzania, eastern Zambia, and northern Zimbabwe, experienced severe declines due to illegal ivory poaching. In contrast, populations in other regions like north Botswana are booming.

“Unchecked growth isn’t necessarily a good thing, however,” says coauthor Stuart Pimm, professor of conservation at Duke University. “Rapidly increasing populations can outgrow and damage their local environment and prove hard to manage—introducing a threat to their long-term stability.”

In addition to documenting local growth rates, the team also looked at the features of the local populations to identify what makes them stable, that is neither growing nor declining.

Elephant populations in well-protected but isolated parks, sometimes called “fortress conservation,” grow rapidly in the absence of threats but are unsustainable in the long term. These elephants will likely need future conservation interventions, such as translocation or birth control, which are both costly and intensive endeavors.

The team found that the most stable populations occur in large, core areas that are surrounded by buffer zones. The core areas are defined by their strong levels of environmental protection and minimal human impact, whereas the buffers allow some activities such as sustainable farming, forestry, or trophy hunting. Unlike the insular fortresses, core areas are connected to other parks, allowing herds to move naturally.

“What’s crucial is that you need a mix of areas with more stable core populations linked to more variable buffer areas,” says lead author Ryan Huang, a Duke PhD now doing postdoctoral research at CERU.

“These buffers absorb immigrants when core populations get too high, but also provide escape routes when elephants face poor environmental conditions or other threats such as poaching,” he says.

Connecting protected areas means elephants can freely move in and out. This allows a natural equilibrium to occur without human intervention, sparing conservationists from using their limited resources to maintain balance.

“Calling for connecting parks isn’t something new. Many have done so,” Huang says. “But surprisingly, there has not been a lot of published evidence of its effectiveness so far. This study helps quantify why this works.”

“Connecting protected areas is essential for the survival of African savanna elephants and many other animal and plant species,” says Celesté Maré, coauthor and doctoral student at Aarhus University in Denmark. “Populations with more options for moving around are healthier and more stable, which is important given an uncertain future from climate change.”

Source: Duke University

People often keep adverse information about themselves secret because they worry that others will judge them harshly, but those fears are overblown, according to new research.

In fact, when study participants pushed through fear to reveal a secret, those in whom they confided were significantly more charitable than they expected.

“When we’re thinking about conveying negative information about ourselves, we’re focused on the content of the message,” says study coauthor Amit Kumar, assistant professor of marketing at the McCombs School of Business at the University of Texas at Austin. “But the recipients are thinking about the positive traits required to reveal this secret, such as trust, honesty, and vulnerability.”

Kumar cites several key takeaways from the 12 experiments in his paper, coauthored with Michael Kardas of Oklahoma State University and Nicholas Epley of the University of Chicago:

Too-Low Expectations. The researchers asked several groups to imagine revealing a negative secret and to predict how another person would judge them. Then they asked each participant to reveal the secret to that person, and they gathered the recipients’ responses. The expected judgment was consistently worse than the actual judgment.

Miscalibrated Expectations. People were driven to reveal or conceal based on how they thought others would evaluate them. “If we believe other people will think we’re less trustworthy, that can really impact our decision to conceal information,” Kumar says.

In the experiments, though, disclosure had the opposite effect. Recipients rated the revealers’ honesty and trustworthiness more highly than the revealers expected.

Across Relationships. Participants divulged secrets to strangers, acquaintances, close friends, family members, and romantic partners—all with similar results.

Says Kumar, “Their expectations were slightly more accurate for close others, but they were still systematically miscalibrated, even for the closest people in their lives.”

Dark vs. Light Secrets. The participants revealed a wide range of negative information, from admitting they had never learned to ride a bike to confessing infidelity. They predicted that more serious secrets would generate worse judgments.

But even for darker secrets, they still overestimated the impact. “The magnitude of what you’re revealing can impact people’s evaluations, but it also impacts your expectations of those evaluations,” Kumar says.

Honesty Feels Good. In one study, the researchers told participants what they had learned: that people overestimate the negative impact of revelations. The news shifted participants’ attitudes toward more openness.

When challenged to confess that they had told a lie, only 56% of participants did. But in another group, where participants were told they would probably not be judged harshly, 92% chose to reveal their lies.

“There’s a psychological burden associated with secrecy,” says Kumar. “If we can alter people’s expectations to make them more in line with reality, they might be more transparent in their relationships.”

Building Trust with Coworkers. Although none of the experiments were run in business settings, Kumar says the lessons can be applied there.

“Any comprehensive understanding of how to navigate the workplace includes a better understanding of how people think, feel, and behave,” he says. “When workplace transgressions arise, people could be wise to consider that they also reveal warmth, trust, and honesty when they are open and transparent about revealing negative information.”

The research appears in the Journal of Personality and Social Psychology.

Source: Judie Kinonen for UT Austin

Bariatric surgery may mitigate the natural history of cognitive decline expected in people with obesity, a new study suggests.

Within the next 10 years, it’s projected that obesity will affect up to 50% of United States adults. Obesity is associated with cognitive impairment and dementia.

The findings, published in the Journal of Nutrition, Health & Aging, show that people with obesity who underwent bariatric surgery had stable cognition two years later.

“Since individuals with obesity experience more rapid cognitive decline than those without, stable cognition two years after bariatric surgery may be considered a success against historical trends, yet future controlled trials are needed to test this,” says first author Evan Reynolds, lead statistician for the NeuroNetwork for Emerging Therapies at the University of Michigan Medicine.

Using a collection of National Institutes of Health memory and language tests, as well as the Rey Auditory Verbal Learning Test, the research team assessed over 85 bariatric surgery patients at two-year follow up.

They found that NIH Cognitive Battery test scores remained stable, with secondary executive function tests showing improvement. One of the memory assessments, however, declined following surgery.

While this current study is the largest to assess changes two years after bariatric surgery, the researchers say, the results conflict with previous studies which found improved memory and executive functioning among similar patients.

“That study was primarily made up of patients who received gastric bypass, while our study was made up primarily of individuals that completed a sleeve gastrectomy,” Reynolds says.

“To provide the best evidence on the effectiveness of bariatric surgery on cognition and potential differences between surgery types, we must conduct larger observational studies or randomized, controlled trials.”

After bariatric surgery, improvements in diabetes complications, such as peripheral neuropathy, chronic kidney disease, and retinopathy, were not associated with improved cognition.

“Metabolic factors, including diabetes and obesity, are associated with cognitive decline, but we still need to better understand how best to treat these factors to improve patients’ cognitive outcomes,” says senior author Brian Callaghan, professor of neurology at the University of Michigan Medical School and a neurologist at University of Michigan Health.

The National Institutes of Health and the National Institute of Diabetes and Digestive and Kidney Diseases supported the work.

Source: University of Michigan

HELSINKI — A newly-completed launch pad on China’s Hainan island could increase China’s access to space, boosting national constellation projects and commercial launch plans.

The first launch pad at Hainan Commercial Launch Site was completed Dec. 29. It is the first of two pads which will host liquid propellant launch vehicles. 

The development will ease a bottleneck of access to launch facilities for both national and commercial launch service providers and allow Chinese entities to speed up plans to launch a range of constellations. It will also increase China’s ability to deploy and maintain space assets, including remote sensing, communications and other systems, for civil and military purposes.

The new launch pads could help China to transition away from older hypergolic rockets. It could help reduce incidents of booster debris falling around inhabited areas following launches from the country’s inland spaceports of Jiuquan, Taiyuan and Xichang.

A first launch from the pad is expected in the first half of 2024. The next expected Long March 8 launch will be the Queqiao-2 lunar relay satellite. That mission is a prerequisite for China to launch the Chang’e-6, a first-ever lunar far side sample return mission.

Hainan Commercial Launch Site is located near the coastal national Wenchang spaceport on the island province of Hainan in the South China Sea. The latter opened in 2014 and hosts launches of China’s new, large kerosene-liquid oxygen rockets, most notably the Long March 5 series.

Despite its proximity to the national spaceport, the new Wenchang site is considered China’s fifth launch site. The country additionally has sea launch facilities on the coast of the Eastern province of Shandong.

The newly-completed Pad 1 is specifically dedicated to the Long March 8, a newer, kerolox medium-lift rocket, developed by the China Aerospace Science and Technology Corp. (CASC), China’s main space contractor. 

China’s Starlink

Previously revealed efforts to mass produce the Long March 8 are linked to China’s plans to construct its 13,000-satellite low Earth orbit broadband megaconstellation. 

The pad will ease a bottleneck which saw the Long March 8 need to use Wenchang spaceport, which is focused mainly on major civil mission launches involving the Long March 5 and 7 series rockets.

China’s launch rate has grown rapidly in recent years, from a national record 22 in 2016, to 55 in 2022 and 67 in 2023. CASC’s overall launch rate dropped from 2022 to 2023 however, as commercial actors accounted for 17 of China’s orbital launches. CASC also continued to rely on older Long March 2, 3 and 4 series rockets which use toxic, hypergolic propellant.

The country will need to greatly increase its launch rate above this background growth to construct the “Guowang” constellation.

SpaceNews understands that China made filings to the International Telecommunications Union (ITU) for Gouwang in 2020. It will need to launch the first satellites using all the frequencies to be brought into use by 2027, and launch 10% of the total number of satellites launched by September 2029. Half of the satellites for the constellation will need to be launched by September 2032. Deployment of the constellation is to be completed two years later.

Meanwhile a Shanghai-based company is also planning another 10,000-plus LEO constellation. The first satellite for the G60 constellation rolled off production lines in December.

Second pad to host “XLV” launcher

A second commercial launch pad is still being constructed on Hainan. It is expected to be completed by the end of May this year. The first launch from that pad will be the “XLV” rocket developed by CASC’s Shanghai Academy of Spaceflight Technology (SAST).

Little has been revealed about the new launcher. There are indications that it could be a 3.8-meter-diameter rocket using four YF-100K kerosene-liquid oxygen engines. 

Pad 2 is described by a social media channel for the new launch site as a universal pad. The new pad will be able to accommodate 19 different launch vehicles. The two Chinese commercial liquid propellant launchers to fly so far—Zhuque-2 and Tianlong-2—have launched from Jiuquan Satellite Launch Center in the Gobi Desert, northwest China.

At least nine manufacturers are thought to be set to utilize the facilities. These include CASC subsidiaries and commercial entities including iSpace, CAS Space and Deep Blue Aerospace. The latter aims to launch its first Nebula-1 reusable rocket from the pad in late 2024.

The new facilities could also help reduce costs, according to launch site officials. “The site was built with strong launching capabilities, as it is expected to put several dozen or even over 100 satellites into orbit each year,” Guo Qiang, director of the Hainan International Commercial Aerospace Launch Co., Ltd., told China Central Television (CCTV). “Beyond that, we are focusing on lowering the costs as the satellites can form a constellation with reduced costs.”

A groundbreaking ceremony for a third pad for hosting solid rocket launches took place in June 2023. The planned construction period was 180 days. Most commercial solid rocket launches have been conducted at Jiuquan. Other launches have taken place using the Haiyang sea launch facilities.

Progress on another planned commercial launch site, near Ningbo in Eastern China, had apparently stalled. A December update suggests however that the project is still active. Local officials visited Hainan commercial spaceport to learn lessons from its construction.

Related

Even small differences in the availability of urban green and blue spaces may be associated with better mental and physical health in older adults, according to a new study.

The findings show that having just 10% more forest space in a person’s residential ZIP code is associated with reduced serious psychological distress, which covers mental health problems that require treatment and interfere with people’s social lives, work, or school.

Similarly, a 10% increase in green space, tree cover, water bodies, or trail length lowers the chance that older people will report their general health as poor or fair.

“Our findings suggest that loss of our urban green and blue spaces due to rapid urbanization may not just have an environmental impact but could have a public health impact as well,” says Adithya Vegaraju, a medical student in the Washington State University SU Elson S. Floyd College of Medicine and first author of the study published in the journal Health & Place.

The study is based on health survey data from more than 42,000 people aged 65 and older who lived in urban areas of Washington state between 2011 and 2019. In their analysis, the researchers related survey respondents’ general and mental health outcomes to different measures that quantified access to green and blue spaces, such as forests, parks, lakes, and rivers, within their residential ZIP codes. Close to 2% of respondents showed signs of serious psychological distress and 19% reported having fair or poor general health.

The researchers presented preliminary findings for this study at an American Academy of Neurology Annual Meeting in April 2023. Those findings looked only at the relationship between serious psychological distress and distance to the closest green and blue space.

In this final published version of the study, the researchers looked at several additional measures, including the percentage of green space, tree canopy, forest area, and open space within ZIP codes as well as the length of trails. They also expanded their analyses to examine how these measures related to self-rated general health and to account for differences in survey respondents’ demographics, such as race and education level.

Though other studies have looked at how proximity to nature might impact health, Vegaraju says this study is one of the first to look at this relationship in older adults in the United States. Older people are especially vulnerable to mental health issues such as depression, which has been shown to increase the risk of cognitive decline and dementia. They are also less likely to receive treatment to manage their mental health conditions.

“Older adults with depression, anxiety or mental health issues are known to be more resistant to medical interventions or talk therapy, which are the go-to treatments for these conditions,” says Vegaraju. “If exposure to green or blue spaces could help prevent, delay, or even treat poor mental health in older adults, we need to look at that more closely as a way to improve mental health outcomes in this population.”

He says one potential solution could involve nature prescriptions, a growing trend that involves healthcare providers giving patients written recommendations to spend time outdoors.

More research needs to be done to know exactly how exposure to green and blue spaces may lead to better mental and general health, says senior author Solmaz Amiri, a research assistant professor in the WSU College of Medicine and a researcher in the Institute for Research and Education to Advance Community Health (IREACH).

She is looking to study the possible link between nature exposure and cognitive decline, which can be an early sign of Alzheimer’s disease or dementia.

“It is thought that exposure to green and blue spaces could help slow cognitive decline,” Amiri says. “What we would like to know is if green and blue space exposure can influence dementia directly or whether it can do so by reducing mental health issues that may lead to cognitive decline.”

Ultimately, she hopes this research will help resolve health inequities among older adults from lower socioeconomic backgrounds, which may be tied to unequal access to green and blue spaces in the urban areas where they live.

Source: Washington State

An octopus that can change the size and color of patterns on its skin has inspired a deception technology platform for use in a variety of fields, including the military, medicine, robotics, and sustainable energy.

With a split-second muscle contraction, the greater blue-ringed octopus can change the size and color of the namesake patterns on its skin for purposes of deception, camouflage, and signaling.

The new devices will benefit from dynamically adjustable fluorescent and spectroscopic properties, ease of manufacturing, and potential for scaling to areas large enough to cover vehicles, billboards, and even buildings, the inventors say.

A study of bio-inspired creation appears in Nature Communications.

Hapalochlaena lunulata is a species of octopus native to the Western Pacific Ocean and Indian Ocean. It uses a neurotoxin venom to stun its prey and can ward off predators with a flash of its blue rings. These iridescent circles on a brown background on the creature’s skin are what drew the researchers’ attention.

“We are fascinated by the mechanisms underpinning the blue-ringed octopus’ ability to rapidly switch its skin markings between hidden and exposed states,” says senior coauthor Alon Gorodetsky, professor of chemical and biomolecular engineering at the University of California, Irvine.

“For this project, we worked to mimic the octopus’ natural abilities with devices from unique materials we synthesized in our laboratory, and the result is an octopus-inspired deception and signaling system that is straightforward to fabricate, functions for a long time when operated continuously, and can even repair itself when damaged.”

The architecture of the innovation calls for a thin film consisting of wrinkled blue rings surrounding brown circles—much like those on the octopus—sandwiched between a topmost transparent proton-conducting electrode and an underlying acrylic membrane, with another identical electrode underneath.

Further technical creativity by the researchers occurs at the molecular level as they explored the use of acenes, which are organic compounds made up of linearly fused benzene rings. Designer nonacene-like molecules (with nine linearly fused rings) used by the team help give the platform some of its outstanding capabilities, according to Gorodetsky.

“For our devices, we conceptualized and designed a nonacene-like molecule with a unique architecture,” says co-lead author Preeta Pratakshya, who recently received her PhD from UCI’s chemistry department. “Acenes are organic hydrocarbon molecules with a host of advantageous characteristics, including ease of synthesis, tunable electronic characteristics, and controllable optical properties.

“Our nonacene-like molecules are exceptional among acenes because they can survive years of storage in air and over a day of continuous irradiation with bright light in air. No other expanded acene displays this combined long-term stability under such harsh conditions.”

The type of molecules used to fabricate the colored blue ring layer are what endow the devices with their most favorable features, including adjustable spectroscopic properties, the facilitation of straightforward benchtop manufacturing, and ambient-atmosphere stability under illumination, Gorodetsky says.

“Our coauthor Sahar Sharifzadeh, a Boston University professor of electrical and computer engineering, demonstrated that the stimuli-responsive properties of the molecules can be computationally predicted, which opens paths for the in silico design of other camouflage technologies.”

In their laboratory tests, the team found that the bioinspired devices could change their visible appearance over 500 times with little or no degradation, and they also could autonomously self-repair without user intervention.

The invention was demonstrated to possess a desirable combination of capabilities in the ultraviolet, visible light, and near-infrared parts of the electromagnetic spectrum, according to Gorodetsky. This would enable the devices to disguise other objects from detection or to clandestinely signal observers.

“The photophysical robustness and general processability of our nonacene-like molecule—and presumably its variants—opens opportunities for future investigation of these compounds within the context of traditional optoelectronic systems such as light-emitting diodes and solar cells,” Gorodetsky says.

Additional coauthors are from UC Irvine and Boston University.

The Office of Naval Research, the Defense Advanced Research Projects Agency, and the National Science Foundation supported the work.

Source: UC Irvine

Researchers have connected two blood biomarkers to changes in cognitive function in women in midlife.

The discovery opens a potentially powerful path to noninvasive, earlier detection and interventions for Alzheimer’s disease and other dementias.

The study analyzed two blood-based serum biomarkers, amyloid β (Aβ)42, Aβ42/40 ratio and phosphorylated tau181 (p-tau181), and tracked their levels in middle-aged women and compared results of a series of neurological function tests.

The findings, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, found that higher levels of p-tau 181 were linked to accelerated cognitive decline and, likewise, lower AB 42/40 levels were associated with faster cognitive decline.

The data came from 192 middle-aged women who the researchers followed for 14 years through the Study on Women’s Health Across the Nation, Michigan Cohort.

“This is a new area of study, and it is very promising, but of course we are in need of a larger and more diverse sample,” says Xin Wang, a research assistant professor in the epidemiology department at the University of Michigan’s School of Public Health.

The findings suggest that midlife blood AD biomarker assessments may serve as early predictors of cognitive decline, offering an opportunity for early detection and prevention before development of irreversible dementia, Wang says.

Besides the possibility of earlier intervention for Alzheimer’s disease and other forms of dementia, the blood biomarker tests such as those the researchers studied could lead to less invasive, possibly more affordable methods of neurological testing, which currently calls for lumbar punctures for cerebral fluid and expensive PET scans for imaging.

“It’s important to note that the presence of the biomarkers that we tested doesn’t mean there is Alzheimer’s disease,” Wang says. “However, we know they are a central part of neuropathological changes. These pathological changes are important to know of earlier than later.”

The researchers chose midlife as a “pivotal period” to test for and identify cognitive decline due to two major changes in women: 1) menopausal transition, which is characterized by sharp reduction in estrogen levels and irreversible ovarian alterations, and leads to a changes in cognitive function, and 2) higher prevalence of cardiometabolic risk factors such as hypertension and diabetes, which are also associated with elevated risk of cognitive decline and dementia in older age.

Wang stresses that the findings are based on “only a very small sample, but the results are promising and an important building block for research with a larger, more diverse sample.”

Additional coauthors are from the University of Michigan, Michigan State, and the Michigan Alzheimer’s Disease Center and Veterans Affairs Ann Arbor Health System.

Source: University of Michigan