Rules on free lateral flow and PCR Covid tests published

The list of who can get free tests after 1 April in England is now out, but most people will have to pay.

Share Button

Time to cut back on caffeine?

Reprint Permissions

A single copy of these materials may be reprinted for noncommercial personal use only. “Mayo,” “Mayo Clinic,” “MayoClinic.org,” “Mayo Clinic Healthy Living,” and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.

Share Button

Solid aerosols found in Arctic atmosphere could impact cloud formation and climate

The Arctic is rapidly losing sea ice, and less ice means more open water, and more open water means more gas and aerosol emissions from the ocean into the air, warming the atmosphere and making it cloudier.

So when researchers from the lab of University of Michigan aerosol scientist Kerri Pratt collected aerosols from the Arctic atmosphere during summer 2015, Rachel Kirpes, then a doctoral student, discovered a curious thing: Aerosolized ammonium sulfate particles didn’t look like typical liquid aerosols.

Working with fellow aerosol scientist Andrew Ault, Kirpes discovered that ammonium sulfate particles, which should have been liquid, were actually solid. The team’s results are published in the Proceedings of the National Academy of Sciences.

Solid aerosols can change how clouds form in the Arctic. And, as the Arctic loses ice, researchers expect to see more of these unique particles formed from oceanic emissions combined with ammonia from birds, which will impact cloud formation and climate. Additionally, understanding the characteristics of aerosols in the atmosphere is critical for improving the ability of climate models to predict current and future climate in the Arctic and beyond.

“The Arctic is warming faster than anywhere else in the world. As we have more emissions from open water in the atmosphere, these types of particles could become more important,” said Pratt, associate professor of chemistry, and earth and environmental sciences. “These types of observations are so critical because we have so few observations to even evaluate the accuracy of models of the Arctic atmosphere.

“With so few observations, sometimes you get surprises like this when you make measurements. These particles didn’t look like anything we had ever seen in the literature, in the Arctic, or anywhere else in the world.”

The aerosols observed in the study were up to 400 nanometers, or about 300 times smaller than the diameter of a human hair. Ault, associate professor of chemistry, says that aerosols in the Arctic are typically assumed to be liquid.

Once the relative humidity of the atmosphere reaches 80% — about the level of a humid day — the particle becomes liquid. When you dry the aerosol back out, it doesn’t turn into a solid until the relative humidity is about 35%-40%. Because the air over the Arctic Ocean — or any ocean — is humid, researchers expect to see liquid aerosols.

“But what we saw is a pretty new phenomenon where a small particle collides with our droplets when it’s below 80% humidity, but above 40% humidity. Essentially, this provides a surface for the aerosol to solidify and become a solid at a higher relative humidity than you would have expected,” Ault said.

“These particles were much more like a marble than a droplet. That’s really important, particularly in a region where there haven’t been a lot of measurements because those particles can eventually end up acting as the seeds of clouds or having reactions happen on them.”

Additionally, the researchers say, the size, composition and phase of atmospheric aerosols impact climate change through water uptake and cloud formation.

“It’s our job to keep helping modelers refine their models,” Ault said. “It’s not that the models are wrong, but they always need more new information as events on the ground change, and what we saw was something completely unexpected.”

Pratt’s team collected aerosols in August-September 2015 in Utqia?vik, the northernmost point of Alaska. To do this, they used what’s called a multistage impactor, a device that has several stages that collect particles according to their size. Kirpes later analyzed these particles in Ault’s lab using microscopy and spectroscopy techniques that can examine the composition and phase of particles less than 100 nanometers in size.

“If we were to go back several decades when there was ice near the shore, even in August and September, we would not be observing these particles. We’re observing the consequences of this climate already changing,” Pratt said. “We need to have the reality captured in models that simulate clouds and the atmosphere, which are critical for understanding the energy budget of the Arctic atmosphere, for this place that is changing faster than anywhere else.”

Share Button

Lack of sleep increases unhealthy abdominal fat, study finds

New research from Mayo Clinic shows that lack of sufficient sleep combined with free access to food increases calorie consumption and consequently fat accumulation, especially unhealthy fat inside the belly.

Findings from a randomized controlled crossover study led by Naima Covassin, Ph.D., a cardiovascular medicine researcher at Mayo Clinic, show that lack of sufficient sleep led to a 9% increase in total abdominal fat area and an 11% increase in abdominal visceral fat, compared to control sleep. Visceral fat is deposited deep inside the abdomen around internal organs and is strongly linked to cardiac and metabolic diseases.

The findings are published in the Journal of the American College of Cardiology, and the study was funded by the National Heart, Lung and Blood Institute.

Lack of sufficient sleep is often a behavior choice, and this choice has become increasingly pervasive. More than one-third of adults in the U.S. routinely do not get enough sleep, in part due to shift work, and smart devices and social networks being used during traditional sleep times. Also, people tend to eat more during longer waking hours without increasing physical activity.

“Our findings show that shortened sleep, even in young, healthy and relatively lean subjects, is associated with an increase in calorie intake, a very small increase in weight, and a significant increase in fat accumulation inside the belly,” says Virend Somers, M.D., Ph.D., the Alice Sheets Marriott Professor of Cardiovascular Medicine, and principal investigator of the study.

“Normally, fat is preferentially deposited subcutaneously or under the skin. However, the inadequate sleep appears to redirect fat to the more dangerous visceral compartment. Importantly, although during recovery sleep there was a decrease in calorie intake and weight, visceral fat continued to increase. This suggests that inadequate sleep is a previously unrecognized trigger for visceral fat deposition, and that catch-up sleep, at least in the short term, does not reverse the visceral fat accumulation. In the long term, these findings implicate inadequate sleep as a contributor to the epidemics of obesity, cardiovascular and metabolic diseases,” says Dr. Somers.

The study cohort consisted of 12 healthy people who were not obese, each spending two 21-day sessions in the inpatient setting. Participants were randomly assigned to the control (normal sleep) group or restricted sleep group during one session and the opposite during the next session, after a three-month washout period. Each group had access to free choice of food throughout the study. Researchers monitored and measured energy intake; energy expenditure; body weight; body composition; fat distribution, including visceral fat or fat inside the belly; and circulating appetite biomarkers.

The first four days were an acclimation period. During this time, all participants were allowed nine hours in bed to sleep. For the following two weeks, the restricted sleep group was allowed four hours of sleep and the control group maintained with nine hours. This was followed by three days and nights of recovery with nine hours in bed for both groups.

The participants consumed more than 300 extra calories per day during sleep restriction, eating approximately 13% more protein and 17% more fat, compared to the acclimation stage. That increase in consumption was highest in the early days of sleep deprivation and then tapered off to starting levels during the recovery period. Energy expenditure stayed mostly the same throughout.

“The visceral fat accumulation was only detected by CT scan and would otherwise have been missed, especially since the increase in weight was quite modest — only about a pound,” Dr. Covassin says. “Measures of weight alone would be falsely reassuring in terms of the health consequences of inadequate sleep. Also concerning are the potential effects of repeated periods of inadequate sleep in terms of progressive and cumulative increases in visceral fat over several years.”

Dr. Somers says behavioral interventions, such as increased exercise and healthy food choices, need to be considered for people who cannot easily avoid sleep disruption, such as shift workers. More study is needed to determine how these findings in healthy young people relate to people at higher risk, such as those who are already obese, or have metabolic syndrome or diabetes.

Story Source:

Materials provided by Mayo Clinic. Original written by Terri Malloy. Note: Content may be edited for style and length.

Share Button

Caribou herd rebounds as Indigenous stewards lead conservation efforts

Despite recovery efforts from federal and provincial governments, caribou populations across Canada continue to decline, largely due to human activity.

But as a new UBC Okanagan study finds, in central British Columbia there is one herd of mountain caribou, the Klinse-Za, whose numbers are going in the opposite direction — all thanks to a collaborative recovery effort led by West Moberly First Nations and Saulteau First Nations.

In partnership with many organizations and governments, the Indigenous-led conservation initiative paired short-term recovery actions such as predator reduction and caribou guardians at maternal pens, with ongoing work to secure landscape-level protection in an effort to create a self-sustaining caribou population.

Their efforts paid off.

Dr. Clayton Lamb, a Liber Ero Fellow, along with Carmen Richter, a biology master’s student, and Dr. Adam T. Ford, Canada Research Chair in Wildlife Restoration Ecology, conduct research in the Irving K. Barber Faculty of Science. Their latest study shows Klinse-Za caribou numbers have nearly tripled in under a decade.

“We have an Indigenous-led conservation effort to thank for averting the looming extinction of this herd,” says Dr. Lamb. “The population was declining rapidly — a West Moberly Elder once described the herd as a ‘sea of caribou,’ but by 2013 it had declined to only 38 animals.”

Today, the herd count is more than 110 and numbers continue to rise.

“This work provides an innovative, community-led, paradigm shift to conservation in Canada,” Dr. Lamb says. “While Indigenous Peoples have been actively stewarding landscapes for a long time, this approach is new in the level of collaboration among western scientists and Indigenous Peoples to create positive outcomes on the land and put an endangered species on the path to recovery.”

Richter, who is a Saulteau First Nations member, says Indigenous communities have really come together for the good of the caribou.

“We are working hard to recover these caribou. Each year, community members pick bags and bags of lichen to feed the mother caribou in the pen while other members live up at the top of the mountain with the animals. One day, we hope to return the herds to a sustainable size,” she says.

Though the partnership has yielded great success, Dr. Ford is the first to acknowledge that more time and effort will be needed to fully recover the Klinse-Za.

“This work is also an important part of decolonizing the mindset of conservation, which has historically worked to exclude the views of Indigenous Peoples,” he adds.

With caribou declines exceeding 40 per cent in recent decades across Canada, many populations have already been lost. But Dr. Ford insists there is a brighter path forward, and this study proves it.

“This is truly an unprecedented success and signals the critical role that Indigenous Peoples can play in conservation,” he says. “I hope this success opens doors to collaborative stewardship among other communities and agencies. We can accomplish so much more when working together.”

This study was co-produced by western scientists and members of West Moberly First Nations and Saulteau First Nations. The work was recently published in Ecological Applications and is supported by a companion manuscript in Ecological Applications exploring the expeditious population growth.

Share Button

Tory MPs call for home early abortion service to be made permanent

Three MPs have urged their colleagues to keep the pandemic policy in place so women can take tablets at home.

Share Button

Teenage social media use linked to less life-satisfaction for some

Survey suggests teenagers may be more vulnerable to social media at particular ages, with heavy use a risk.

Share Button

Alzheimer’s: Neil Kinnock supporting wife through disease

The ex-Labour leader says his wife Glenys, who has Alzheimer’s, has been “a continent of rocks”.

Share Button

Essex mental health services inquiry probes 1,500 deaths

England’s first public inquiry into a mental health service appeals for more people to come forward.

Share Button

Ukraine: Premature babies struggling for life in bombed cities

Doctors have begun seeing a sharp rise in the number of preterm births in some areas of Ukraine.

Share Button