The study, published in Scientific Reports, used an animal model of drug addiction to show that a return to social interaction gives the same result as living in a rich, stimulating environment in reducing cravings for both sugar and nicotine rewards.

“This was an animal study, but we can probably all relate to the mental health benefits of being able to go for a coffee with our friends and having a chat,” lead author Dr Kelly Clemens from UNSW Sydney’s School of Psychology said. “Those sorts of activities can divert our attention from being at home and eating and drinking — but they can also be rewarding in and of themselves, and we come away from those interactions feeling relaxed, happy and valued in a way that means our general demeanour and mental health has improved.”

Prior to the COVID-19 pandemic, social isolation was already increasing in Australia, with almost a quarter of Australians reporting feelings of loneliness or social isolation. The researcher said social isolation could have a significant impact on both mental and physical health. It can lead to anxiety, depression, compulsive overeating, and an increased risk of cardiovascular disease and cancer. “Social isolation in particular can both lead to increased drug taking, but can also make it harder for those wanting to cut down or quit,” Dr Clemens said.

The UNSW Scientia Fellow is interested in why people relapse into drug use — in this case, nicotine — when they are socially isolated. “We know that if you’re a regular smoker and you’re trying to give up and then you see somebody else smoking on tv, smell cigarette smoke, or you see a packet of cigarettes, people experience very strong cravings,” she said. “So we wanted to know if isolation increases the likelihood of picking up on those cues, and of initiating cravings.”

Existing evidence tells us that both people and rodents who are anxious, or in a socially isolated environment, pay more attention to substance cues in their environment, she said. These cues are more likely to enter into their long-term memory. “And they can actually have a bigger influence over behaviour later on,” she said.

While many studies have focused on the effect of isolation on adolescents, Dr Clemens concentrated on adult rats in this research. The researcher examined how cues linked to nicotine intake influenced cravings in adult rats in social isolation, and if the cravings could be reversed by returning the animals to group housing. They measured cravings by recording the amount of times the rat pressed a lever to turn on the cue that had been linked to nicotine. The team found that after a brief period of abstinence, the socially isolated rats were much more likely to relapse to nicotine seeking. But their cravings were reversed once they returned to group housing, highlighting the importance of social interaction in the treatment of substance abuse disorders.

“When we put the rats back with their cage mates, they weren’t interested in the cue for the nicotine anymore, and they showed little evidence of relapse,” Dr Clemens said. “The key finding of this particular study is the reversal of susceptibility to relapse with that return to group housing.”

Dr Clemens said she was surprised that the benefit of returning to a social environment was so rapid. “The impact of social isolation took much longer to manifest, suggesting that social interaction may have a lasting protective effect against the development and relapse of addiction,” she said.

The Scientia Fellow said the research demonstrated the consequences of social isolation for drug use are not permanent. “Smokers who want to quit are often provided with a pharmacological response to their addiction. They can access many medications and replacement therapies that can have variable results,” she said. “Our findings suggest that something as simple as socialising with your friends could reduce those cravings and make you less likely to smoke.

This is consistent with other recent evidence that suggested people crave social interaction, and that isolation interacts with the brain’s reward circuitry. “But it’s important to note that this was research done in animals, and how exactly it translates to human behaviour needs to be the subject of further research.”

While the study focused on nicotine, Dr Clemens found a similar result from sugar which was used as a control measure in the study. “This tells us that our results probably extend to other high fat, high sugar food and drinks. It is possible that if we did a similar study with alcohol, and other drugs of abuse, we might find a similar pattern. But we would have to test that specifically.”

Dr Clemens said a follow up study could investigate if social isolation is leading to long term or transient changes in the brain that underlie the behavioural changes that she observed.

Researchers want to develop gels for healthcare applications by mixing in medicinal compounds, and giving patients injections so that the gel releases the active pharmaceutical ingredient over a period of months to avoid weekly or daily needle sticks.

But standing in the way is a problem that’s as easily understandable as the difference between using hair gel on a beach versus in a blizzard — heat and cold change the character of the gel.

“We can make gels with the right slow-release properties at room temperature but once we injected them, body heat would rapidly dissolve them and release the medicines too quickly,” said Eric Appel, assistant professor of materials science and engineering.

In a paper published Feb. 2 in the journal Nature Communications, Appel and his team detail their successful first step toward making temperature-resistant, injectable gels with a concoction designed to cleverly bend the laws of thermodynamics.

Appel explained the science behind this rule-breaking with an analogy to making Jello: the solid ingredients are poured into water, then heated and stirred to mix well. As the mixture cools, the Jello solidifies as the molecules bond together. But if the Jello is reheated, the solid reliquefies.

The Jello example illustrates the interplay between two thermodynamic concepts — enthalpy, which measures the energy added to or subtracted from a material, and entropy, which describes how energy changes make a material more or less orderly at the molecular level. Appel and his team had to make a medicinal Jello that didn’t melt, thus losing its time-release properties, when the cool solid was heated by the body.

To accomplish this, the Stanford team created a gel made of two solid ingredients — polymers and nanoparticles. The polymers were long, spaghetti-like strands that have a natural propensity to get entangled, and the nanoparticles, only 1/1000th the width of a human hair, encouraged that tendency. The researchers began by separately dissolving the polymers and particles in water and then stirring them together. As the commingling ingredients began to bond, the polymers wrapped tightly around the particles. “We call this our molecular Velcro,” said first author Anthony Yu, who did the work as a Stanford graduate student and is now a postdoctoral scholar at MIT.

The powerful affinity between the polymers and particles squeezed out the water molecules that had been caught between them, and as more polymers and particles congealed, the mixture began to gel at room temperature. Crucially, this gelling process was achieved without adding or subtracting energy. When the researchers exposed this gel to the body’s temperature (37.5 C) it did not liquefy like ordinary gels because the molecular Velcro effect enabled entropy and enthalpy — orderliness and temperature change, respectively — to remain roughly in balance in accord with thermodynamics.

Appel said it will take more work to make injectable, time-release gels safe for human use. While the polymers in these experiments were biocompatible, the particles were derived from polystyrene, which is commonly used to make disposable cutlery. His lab is already trying to make these thermodynamically-neutral gels with fully biocompatible components.

If they are successful, a time-release gel could prove valuable for providing anti-malarial or anti-HIV treatments in under-resourced areas where it’s difficult to administer the short-acting remedies currently available.

“We are trying to make a gel that you could inject with a pin, and then you’d have a little blob that would dissolve away very slowly for three to six months to provide continuous therapy,” Appel said. “This would be a game-changer for fighting critical diseases around the world.”

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Materials provided by Stanford University School of Engineering. Original written by Tom Abate. Note: Content may be edited for style and length.

While seen as a pest on farmland — for example, when competing with livestock for resources — they usually aren’t widely seen as a pest in conservation areas.

But a new collaborative study led by UNSW Sydney found that conservation reserves are showing signs of kangaroo overgrazing — that is, intensive grazing that negatively impacts the health and biodiversity of the land.

Surprisingly, the kangaroos’ grazing impacts appeared to be more damaging to the land than rabbits, an introduced species.

“The kangaroos had severe impacts on soils and vegetation that were symptomatic of overgrazing,” says Professor Michael Letnic, senior author of the paper and professor in conservation biology and ecosystem restoration at UNSW Science.

“Not only did the areas grazed by overabundant kangaroos have fewer species of plants, but the soils were depleted in nutrients and were compacted — which means that less water can be absorbed by the soil when it rains.”

The findings, published late last year in Global Ecology and Conservation, are based on fieldwork conducted in conservation areas during the drought in 2018. The researchers made observations across four conservation reserves in semi-arid parts of the country.

While kangaroos and rabbits can roam freely in these areas, each reserve has several small ‘exclosures’ — fenced sections designed to keep unwanted animals out — to help native vegetation regenerate. These areas excluded either rabbits, kangaroos, or both.

The team compared the health of the soil and vegetation inside the exclosures with the areas outside. They looked for signs of land degradation specific to each species and monitored animal populations in the area.

Kangaroos were the most populous herbivore across all reserves.

“We tend to think of kangaroo grazing as a natural process because they’re a native species, but there are now too many kangaroos in conservation reserves,” says Prof. Letnic. “Their grazing can be detrimental for biodiversity conservation.

“We need to start thinking about developing strategies to restore the balance and reduce the adverse impacts of overgrazing — particularly during times of drought.”

Dr Graeme Finlayson, SA Arid Rangeland ecologist for Bush Heritage, says overgrazing had dire implications for other native species who rely on vegetation cover and associated food resources to survive. Bush Heritage owns and manages Boolcoomatta Reserve, one of the conservation sites included in this study.

“One of the key species that is likely to be impacted by overgrazing is the critically endangered Plains Wanderer (Pedionomus torquatus), of which there are less than 1000 left in the wild,” he says. “Despite sighting three birds at Boolcoomatta in May 2019, monitoring on the reserve has failed to detect any birds since then.

“Overgrazing and then a two-year drought which have greatly reduced cover and food resources are likely to be key drivers behind this.”

A dry and delicate ecosystem

Ecosystems are fragile and can be thrown off-balance by an overabundance of one species.

For example, kangaroo overgrazing leads to a lower plant diversity — and fewer plants means less food and shelter for other animals.

Dr Charlotte Mills, lead author of the study and visiting fellow at UNSW Science, hopes that this study paves the way for future research into how threatened species might be affected by kangaroo overgrazing.

“There isn’t a lot of research about how kangaroos differentially affect different parts of the ecosystem,” she says. “A lot of past research has focused on rabbits.”

The team found that rabbits still had negative impacts on the land — for example, there were more woody plants in exclosures that rabbits couldn’t get to — but not to the same degree as kangaroos.

“Rabbits and other introduced herbivores like goats are often considered the main contributor to overgrazing in Australia,” says Dr Mills.

“But we found kangaroos had a greater impact on the land — and on the grass in particular.”

Human intervention is a key contributing factor to the growth of kangaroo populations.

“Humans have been culling dingoes — kangaroos natural predators,” says Prof. Letnic.

“We’ve been making it easier for kangaroos to thrive.”

Rethinking conservation practices

Conservation reserves help protect native vegetation from threats like grazing from livestock or introduced species like rabbits or goats.

The findings suggest native species might need to be kept in check, too.

“If we aren’t managing threats that have been exacerbated by human activities — such as overabundant kangaroo populations — then we’re not using conservation areas in the best way that we can,” says Dr Mills.

Prof. Letnic says that while kangaroo populations on farms have been managed for 100 years, they have generally been unmanaged on conservation reserves.

“This research changes thinking by suggesting it’s time to ask some questions,” he says. “We need to ask whether there are too many kangaroos and if they’re having unacceptable impacts on our conservation reserves.”

Dr Finlayson says it’s a difficult balance to get right, but a humane and science-led approach is best for the entire ecosystem.

“Reducing total grazing pressure clearly has great conservation benefit but can be a challenging issue when this requires the management of native species, such as kangaroos,” he says.

“We need to make sure we have a landscape-wide strategy, working across government, conservation and agriculture, to ensure we tackle this problem together, and in the most humane way possible.”

Clive Randall, director of Penn State’s Materials Research Institute (MRI), developed the material and device in partnership with researchers from QorTek, a State College, Pennsylvania-based company specializing in smart material devices and high-density power electronics.

“NASA’s need was how to power electronics in remote locations where batteries are difficult to access for changing,” Randall said. “They also wanted self-powering sensors that monitor systems such as engine stabilities and have these devices work during rocket launches and other high-temperature situations where current piezoelectrics fail due to the heat.”

Piezoelectric materials generate an electric charge when rapidly compressed by a mechanical force during vibrations or motion, such as from machinery or an engine. This can serve as a sensor to measure changes in pressure, temperature, strain or acceleration. Potentially, piezoelectrics could power a range of devices from personal electronics like wristband devices to bridge stability sensors.

The team integrated the material into a version of a piezoelectric energy harvester technology called a bimorph that enables the device to act either as a sensor, an energy harvester or an actuator. A bimorph has two piezoelectric layers shaped and assembled to maximize efficient energy harvesting. Sensors and energy harvesters, while bending the bimorph structure, generate an electrical signal for measurement or act as a power source.

Unfortunately, these functions work less-effectively in high-temperature environments. Current state-of-the-art piezoelectric energy harvesters are normally limited to a maximum effective operating temperature range of 176 degrees Fahrenheit (80 degrees Celsius) to 248 degrees Fahrenheit (120 degrees C).

“A fundamental problem with piezoelectric materials is their performance starts to drop pretty significantly at temperatures above 120 C, to the point where above 200 C (392 F) their performance is negligible,” Gareth Knowles, chief technical officer of QorTek, said. “Our research demonstrates a possible solution for that for NASA.”

The new piezoelectric material composition developed by the researchers showed a near-constant efficient performance at temperatures up to 482 F (250 C). In addition, while there was a gradual drop-off in performance above 482 F (250°C), the material remained effective as an energy harvester or sensor at temperatures to well-above 572 F the researchers reported in the Journal of Applied Physics.

“The compositions performing just as well at these high temperatures as they do at room temperature is a first, as no one has ever managed piezoelectric materials that effectively operate at such high temperatures,” Knowles said.

Another benefit of the material was an unexpectedly high level of electricity production. While at present, piezoelectric energy harvesters are not at the level of more efficient power producers such as solar cells, the new material’s performance was strong enough to open possibilities for other applications, according to Randall.

“The energy production part of this was very impressive, the material shows record performance efficiencies as a piezoelectric energy harvester,” Randall said. “This would potentially enable a continuous, battery-free power supply in dark or concealed environments such as inside an automotive system or even the human body.”

Both Randall and Knowles noted that the partnership between Penn State and QorTek, which goes back over 20 years, enabled development of the new, improved piezoelectric material by complementing each other’s resources.

“In general, a big benefit of a partnership like this is you can tap into the large knowledge reservoir in the field that MRI and Penn State has and that small companies like ours sometimes do not,” Knowles said. “Another benefit is often universities have physical resources such as equipment that again, you won’t ordinarily find inside a small company.”

Randall noted that since QorTek has many employees who are Penn State alumni, there is a familiarity with both the research subject and the people involved.

“One of my post-doctoral researchers and first author on the paper, Wei-Ting Chen, was hired by QorTek so there was a transfer of expertise in that case,” Randall said. “Also, the skillsets offered by QorTek such as mechanical engineering, device design and measurement expertise pushed development at a much faster rate than would be possible given the budget we were given. So the partnership enabled a really fruitful amplification of the project.”

The National Aeronautics and Space Administration’s Small Business Technology Transfer Program and the National Science Foundation funded this research.

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Materials provided by Penn State. Original written by Jamie Oberdick. Note: Content may be edited for style and length.

“Students who participated in the study were twice as likely to meet the state standards in their mathematics achievement,” said Neuharth-Pritchett. “School becomes more challenging as one progresses through the grades, and so if in middle school, students are still twice as likely to meet the state standards, it’s clear that something that happened early on was influencing their trajectory.”

The study found that, in fourth through seventh grades, the odds of a pre-K participant in the study meeting Georgia’s state academic standards on the statewide standardized test were 1.67-2.10 times greater than the odds for a nonparticipant, providing evidence of sustained benefits of state-funded pre-K programs.

“Pre-K is a critical space where children experience success, and it sets them on a trajectory for being successful as they make the transition to kindergarten,” she said. “The hope is that when children are successful early in school, they are more likely to be engaged as they progress and more likely to complete high school.”

Although quality learning experiences during the early years of development have been shown to provide the skills and knowledge for later mathematics achievement, access and entry to high-quality preschool programs remain unequal across the nation.

“Our study looked at a high-needs school district that enrolled children from vulnerable situations in terms of economics and access to early learning experiences,” said Neuharth-Pritchett. “A number of the children in the study had not had any other formative experiences before they went to kindergarten.”

Educational experiences are seen as foundational to later school success with some studies documenting other beneficial outcomes for students who attend pre-K, including a higher chance to complete high school, less mental health concerns, less reliance on the welfare system and more. However, students from low-income families often have more limited opportunities to learn at home as well as in pre-K programs.

While some families are knowledgeable about providing their children with basic mathematical concepts and other foundational skills for a smooth home to school entry, other families might not be aware of the expectations for having mastered a number of these foundational skills before entering kindergarten.

“Equal access to pre-K education has a long history that goes all the way back to the war on poverty. Part of the thinking during the 1960s was that such early learning opportunities would provide the high-quality preschool education that could level the educational playing field between those with economic resources and those without,” she said. “Our study indicated sustained benefits for children’s early learning experiences that persist into the elementary and middle school years.”

Some implications of the study for policymakers to consider include ensuring more equitable access to pre-K programs and hiring highly skilled teachers to promote children’s learning and development. More than half of the pre-K teachers involved in the study held either a master’s or specialist degree, indicating the importance and influence of high-quality, experienced instructors on children’s academic success.

Because of a change in program support for the Georgia Prekindergarten Program during Gov. Nathan Deal’s term, a high proportion of pre-K teachers are now very early in their teaching careers.

Along with Jisu Han, an assistant professor at Kyung Hee University and co-author of the study, Neuharth-Pritchett plans to continue following the study’s participants as they progress through high school.

“The state of Georgia invests substantial resources into this program, so it’s good that these outcomes can be cited for its efficacy,” said Neuharth-Pritchett. “The data from this study gives a much more longitudinal view of success and suggests these programs contribute to children’s education and success. Our results ultimately contribute to evidence supporting early learning and factors influencing long-term academic success for Georgia’s children.”

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Materials provided by University of Georgia. Note: Content may be edited for style and length.