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No, COVID-19 Vaccines Do Not Cause Infertility - Not Getting It Might

sb admin — Fri, 21 Jan 2022 01:17:23 +0000

No, COVID-19 Vaccines Do Not Cause Infertility - Not Getting It Might

Despite claims of anti-vaccine activists no different than groups that used to claim vaccines cause autism, COVID-19 vaccines do not impact fecundability—the probability of conception per menstrual cycle—in female or male partners who received the Pfizer-BioNTech, Moderna, or Johnson & Johnson vaccines.

The prospective study instead indicates that COVID-19 infection among males may temporarily reduce fertility— an outcome that could be avoidable through vaccination.

Lead author Dr. Amelia Wesselink, epidemiologist at Boston University School of Public Health, and colleagues analyzed survey data on COVID-19 vaccination and infection, and fecundability, among female and male participants in the BUSPH-based Pregnancy Study Online (PRESTO), an ongoing NIH-funded study that enrolls women trying to conceive, and follows them from preconception through six months after delivery. Participants included 2,126 women in the US and Canada who provided information on sociodemographics, lifestyle, medical factors, and characteristics of their partners from December 2020 to September 2021, and the participants were followed in the study through November 2021.

The researchers calculated the per menstrual cycle probability of conception using self-reported dates of participants’ last menstrual period, typical menstrual cycle length, and pregnancy status. Fertility rates among female participants who received at least one dose of a vaccine were nearly identical to unvaccinated female participants. Fecundability was also similar for male partners who had received at least one dose of a COVID-19 vaccine compared with unvaccinated male participants. Additional analyses that considered the number of vaccine doses, brand of vaccine, infertility history, occupation, and geographic region also indicated no effect of vaccination on fertility.

While COVID-19 infection was not strongly associated with fertility, men who tested positive for COVID within 60 days of a given cycle had reduced fertility compared to men who never tested positive, or men who tested positive at least 60 days prior. This data supports previous research that has linked COVID-19 infection in men with poor sperm quality and other reproductive dysfunction.

“These data provide reassuring evidence that COVID vaccination in either partner does not affect fertility among couples trying to conceive,” says study senior author Dr. Lauren Wise, professor of epidemiology at BUSPH. “The prospective study design, large sample size, and geographically heterogeneous study population are study strengths, as was our control for many variables such as age, socioeconomic status, preexisting health conditions, occupation, and stress levels.”

The new data also help quell concerns about COVID-19 vaccines and fertility that arose from anecdotal reports of females experiencing menstrual cycle changes following vaccination.

sb admin Thu, 01/20/2022 - 20:17

Categories

Medicine

Liangzhu, Venice of the Stone Age, Collapsed Due To Climate Change

sb admin — Thu, 02 Dec 2021 08:41:56 +0000

Liangzhu, Venice of the Stone Age, Collapsed Due To Climate Change

In the Yangtze Delta, about 160 kilometres southwest of Shanghai, the archeological ruins of Liangzhu City are located. There, a highly advanced culture blossomed about 5,300 years ago, thanks to the engineering of large hydraulic structures.

The walled city had a complex system of navigable canals, dams and water reservoirs. This system made it possible to cultivate very large agricultural areas throughout the year. In the history of human civilization, it is one of the first examples of highly developed communities based on a water infrastructure.

And they did it all without metal.

Long undiscovered, the archaeological site is now considered a well-preserved record of Chinese civilisation dating back more than 5000 years and was declared a UNESCO World Heritage Site in 2019. However, the advanced civilization of this city came to an abrupt end.

"A thin layer of clay was found on the preserved ruins, which points to a possible connection between the demise of the advanced civilization and floods of the Yangtze River or floods from the East China Sea. No evidence could be found for human causes such as warlike conflicts," explains Christoph Spötl of the University of Innsbruck.

The dripstones of Shennong Cave (pictured) and Jiulong Cave provide an accurate glimpse into the time of the Liangzhu culture's collapse about 4300 years ago. Credit: Haiwei Zhang

Dripstones store the answer

Caves and their deposits, such as dripstones, are among the most important climate archives that exist. They allow the reconstruction of climatic conditions above the caves up to several 100,000 years into the past. Since it is still not clear what caused the sudden collapse of the Liangzhu culture, the research team searched for suitable archives in order to investigate a possible climatic cause of this collapse.

Geologist Haiwei Zhang from Xi'an Jiaotong University in Xi'an took samples of stalagmites from the two caves Shennong and Jiulong, which are located southwest of the excavation site.

Data from the stalagmites show that between 4345 and 4324 years ago there was a period of extremely high precipitation. Evidence for this was provided by the isotope records of carbon, which were measured at the University of Innsbruck. The precise dating was done by uranium-thorium analyses at Xi'an Jiaotong University, whose measurement accuracy is ± 30 years.

The massive monsoon rains probably led to such severe flooding of the Yangtze and its branches that even the sophisticated dams and canals could no longer withstand these masses of water, destroying Liangzhu City and forcing people to flee. The very humid climatic conditions continued intermittently for another 300 years, as the geologists show from the cave data.

Citation: Haiwei Zhang, Hai Cheng, Ashish Sinha, Christoph Spötl, Yanjun Cai et al. Collapse of the Liangzhu and other Neolithic cultures in the lower Yangtze region in response to climate change. Sci. Adv., 2021 DOI: 10.1126/sciadv.abi9275

sb admin Thu, 12/02/2021 - 03:41

Categories

Physical Sciences

Genetically Rescued Organism: Toward A Solution For Sudden Oak Death

sb admin — Mon, 08 Nov 2021 22:47:18 +0000

Genetically Rescued Organism: Toward A Solution For Sudden Oak Death

Sudden oak death, caused by the pathogen Phythophthora ramorum, is one of the most ecologically devastating forest diseases in North America, responsible for the deaths of millions of oaks and tanoaks along the coast.

Science to the rescue? After the success of genetically modified organisms in things like insulin and food, a recent trend is Genetically Rescued Organisms. These GROs would use science to create natural resistance, like a vaccine for plants, and reduce the impact of altered species composition, released carbon pools, and greater fire risk the deaths bring.

Before that can happen, scientists need to better understand the basic biology of Phythophthora ramorum, including how well it sporulates on common plants.

Image by RegalShave from Pixabay

Scientists at the University of California, Davis, set out to investigate the sporulation potential of this pathogen on common California plant species. They collected leaves from 13 common plant hosts in the Big Sur-region and inoculated them with the causal pathogen. They found that most of the species produced spores, though there was a ride range, with bay laurel and tanoak producing significantly more sporangia than the other species. They also observed an inconsistent relationship between sporulation and lesion size, indicating that visual symptoms are not a reliable metric of sporulation potential.

“Our study is the first to investigate the sporulation capacity on a wide range of common coastal California native plant species and with a large enough sample size to statistically distinguish between species," explained first author Dr. Lisa Rosenthal. "It largely confirms what was previously reported in observational field studies – that tanoak and bay laurel are the main drivers of sudden oak death infections—but also indicates that many other hosts are capable of producing spores.”

Citation: Lisa M. Rosenthal, Sebastian N. Fajardo, and David M. Rizzo, Sporulation Potential of Phytophthora ramorum Differs Among Common California Plant Species in the Big Sur Region, Plant Disease 17 Aug 2021 https://doi.org/10.1094/PDIS-03-20-0485-RE

sb admin Mon, 11/08/2021 - 17:47

Categories

Life Sciences

Doomscrolling COVID-19 News Takes an Emotional Toll - Here is How to Prevent That

sb admin — Fri, 22 Oct 2021 22:03:40 +0000

Doomscrolling COVID-19 News Takes an Emotional Toll - Here is How to Prevent That

Picture this: it’s April 2020, you’re between Zoom meetings, and scrolling through your social media newsfeed. Headlines like “Death toll continues to rise”, “COVID-19 may cause long-term health implications” and “Health-care systems overwhelmed” flash across your screen. Your mood takes a dive, but you can’t stop scrolling.

If this scenario rings true for you, you’re not alone. Research shows people have a tendency to seek out information during uncertain times – it’s a natural coping mechanism. But is persistent information-seeking on social media, sometimes called doomscrolling, helpful during a pandemic, or any time?

Research on the effects of bad news on mood more generally suggest exposure to negative COVID news is likely to be detrimental to our emotional wellbeing. And indeed, early evidence on the effects of COVID news consumption on mental distress reflected this. For instance, one study conducted in March 2020 involving more than 6,000 Americans found that the more time participants spent consuming COVID news in a day, the unhappier they felt.

These findings are striking but leave a few key questions unanswered. Does doomscrolling make people unhappy, or are unhappy people just more likely to doomscroll? How much time spent doomscrolling is a problem? And what would happen if, instead of doomscrolling, we were “kindness scrolling” – reading about humanity’s positive responses to a global crisis?

To find out, we conducted a study where we showed hundreds of people real-world content on either Twitter or YouTube for two to four minutes. The Twitter feeds and YouTube videos featured either general news about COVID, or news about kindness during COVID. We then measured these participants’ moods using a questionnaire, and compared their moods with participants who did not engage with any content at all.

People who were shown general COVID-related news experienced lower moods than people who were shown nothing at all. Meanwhile, people who were shown COVID news stories involving acts of kindness didn’t experience the same decline in mood, but also didn’t gain the boost in mood we’d predicted.

These findings suggest that spending as little as two to four minutes consuming negative news about COVID-19 can have a detrimental impact on our mood.

Although we didn’t see an improvement in mood among participants who were shown positive news stories involving acts of kindness, this may be because the stories were still related to COVID. In other research, positive news stories have been associated with improvements in mood.

Making your social media a more positive place

Our research was published earlier this month. Ironically, news coverage of our findings, with headlines such as “Just five minutes spent on social media is enough to make you miserable, study finds”, could be part of a person’s doomscrolling content.

But we didn’t find that all social media use makes people miserable. Rather, we found that consuming negative content about COVID via Twitter or YouTube in the midst of a pandemic does.

So what can we do to look after ourselves, and make our time on social media more pleasurable?

We found that just a few minutes consuming negative news about COVID-19 can have a detrimental impact on our mood. Nuchylee/Shutterstock

One option is to delete our social media accounts altogether. Figures show almost half of Facebook users in the UK and the US considered leaving the platform in 2020.

But how realistic is it to distance ourselves from platforms that connect nearly half of the world’s population, particularly when these platforms offer social interactions at a time when face-to-face interactions can be risky, or impossible?

Given that avoidance might not be practical, here are some other ways to make your experience on social media more positive.

Be mindful of what you consume on social media. If you log on to connect with other people, focus on the personal news and photos shared instead of the latest headlines.
Seek out content that makes you happy to balance out your newsfeed. This may be images of cute kittens, beautiful landscapes, drool-worthy food videos or something else. You could even follow a social media account dedicated to sharing only happy and positive news.
Use social media to promote positivity and kindness. Sharing good things that are happening in your life can improve your mood, and your positive mood can spread to others. You may also like to compliment others on social media. While this might sound awkward, people will appreciate it more than you think.

Importantly, we’re not suggesting that you avoid all news and negative content. We need to know what’s happening in the world. However, we should also be mindful of our mental health.

As the pandemic continues to alter our lives and newsfeeds, our findings highlight the importance of being aware of the emotional toll negative news takes on us. But there are steps we can take to mitigate this toll and make our social media a happier place.

By Kathryn Buchanan, Lecturer, Psychology Department, University of Essex; Gillian Sandstrom, Senior Lecturer, Department of Psychology, University of Essex; Lara Aknin, Distinguished Associate Professor of Psychology, Simon Fraser University, and Shaaba Lotun, PhD candidate, Department of Psychology, University of Essex. This article is republished from The Conversation under a Creative Commons license. Read the original article.

sb admin Fri, 10/22/2021 - 18:03

Categories

Social Sciences

Appreciating van Leeuwenhoek: The Cloth Merchant Who Discovered Microbes

sb admin — Tue, 06 Apr 2021 14:49:13 +0000

Appreciating van Leeuwenhoek: The Cloth Merchant Who Discovered Microbes

Imagine trying to cope with a pandemic like COVID-19 in a world where microscopic life was unknown. Prior to the 17th century, people were limited by what they could see with their own two eyes. But then a Dutch cloth merchant changed everything.

His name was Antonie van Leeuwenhoek, and he lived from 1632 to 1723. Although untrained in science, Leeuwenhoek became the greatest lens-maker of his day, discovered microscopic life forms and is known today as the “father of microbiology.”

Visualizing ‘animalcules’ with a ‘small see-er’

Leeuwenhoek opened the door to a vast, previously unseen world. J. Verolje/Wellcome Collection, CC BY

Leeuwenhoek didn’t set out to identify microbes. Instead, he was trying to assess the quality of thread. He developed a method for making lenses by heating thin filaments of glass to make tiny spheres. His lenses were of such high quality he saw things no one else could.

This enabled him to train his microscope – literally, “small see-er” – on a new and largely unexpected realm: objects, including organisms, far too small to be seen by the naked eye. He was the first to visualize red blood cells, blood flow in capillaries and sperm.

Drawings from a Leeuwenhoek letter in 1683 illustrating human mouth bacteria. Huydang2910, CC BY-SA

Leeuwenhoek was also the first human being to see a bacterium – and the importance of this discovery for microbiology and medicine can hardly be overstated. Yet he was reluctant to publish his findings, due to his lack of formal education. Eventually, friends prevailed upon him to do so.

He wrote, “Whenever I found out anything remarkable, I thought it my duty to put down my discovery on paper, so that all ingenious people might be informed thereof.” He was guided by his curiosity and joy in discovery, asserting “I’ve taken no notice of those who have said why take so much trouble and what good is it?”

When he reported visualizing “animalcules” (tiny animals) swimming in a drop of pond water, members of the scientific community questioned his reliability. After his findings were corroborated by reliable religious and scientific authorities, they were published, and in 1680 he was invited to join the Royal Society in London, then the world’s premier scientific body.

Leeuwenhoek was not the world’s only microscopist. In England, his contemporary Robert Hooke coined the term “cell” to describe the basic unit of life and published his “Micrographia,” featuring incredibly detailed images of insects and the like, which became the first scientific best-seller. Hooke, however, did not identify bacteria.

Despite Leuwenhoek’s prowess as a lens-maker, even he could not see viruses. They are about 1/100th the size of bacteria, much too small to be visualized by light microscopes, which because of the physics of light can magnify only thousands of times. Viruses weren’t visualized until 1931 with the invention of electron microscopes, which could magnify by the millions.

An image of the hepatitis virus courtesy of the electron microscope. E.H. Cook, Jr./CDC via Associated Press

A vast, previously unseen world

Leeuwenhoek and his successors opened up, by far, the largest realm of life. For example, all the bacteria on Earth outweigh humans by more than 1,100 times and outnumber us by an unimaginable margin. There is fossil evidence that bacteria were among the first life forms on Earth, dating back over 3 billion years, and today it is thought the planet houses about 5 nonillion (1 followed by 30 zeroes) bacteria.

Some species of bacteria cause diseases, such as cholera, syphilis and strep throat; while others, known as extremophiles, can survive at temperatures beyond the boiling and freezing points of water, from the upper reaches of the atmosphere to the deepest points of the oceans. Also, the number of harmless bacterial cells on and in our bodies likely outnumber the human ones.

Viruses, which include the coronavirus SARS-CoV-2 that causes COVID-19, outnumber bacteria by a factor of 100, meaning there are more of them on Earth than stars in the universe. They, too, are found everywhere, from the upper atmosphere to the ocean depths.

A visualization of the human rhinovirus 14, one of many viruses that cause the common cold. Protein spikes are colored white for clarity. Thomas Splettstoesser, CC BY-SA

Strangely, viruses probably do not qualify as living organisms. They can replicate only by infecting other organisms’ cells, where they hijack cellular systems to make copies of themselves, sometimes causing the death of the infected cell.

It is important to remember that microbes such as bacteria and viruses do far more than cause disease, and many are vital to life. For example, bacteria synthesize vitamin B12, without which most living organisms would not be able to make DNA.

Likewise, viruses cause diseases such as the common cold, influenza and COVID-19, but they also play a vital role in transferring genes between species, which helps to increase genetic diversity and propel evolution. Today researchers use viruses to treat diseases such as cancer.

Scientists’ understanding of microbes has progressed a long way since Leeuwenhoek, including the development of antibiotics against bacteria and vaccines against viruses including SARS-CoV-2.

But it was Leeuwenhoek who first opened people’s eyes to life’s vast microscopic realm, a discovery that continues to transform the world.

By Richard Gunderman, Chancellor's Professor of Medicine, Liberal Arts, and Philanthropy, Indiana University. This article is republished from The Conversation under a Creative Commons license. Read the original article.

sb admin Tue, 04/06/2021 - 10:49

Categories

Life Sciences

The Increase in Infant Milk Formulas and Why It Matters

sb admin — Mon, 07 Dec 2020 23:21:44 +0000

The Increase in Infant Milk Formulas and Why It Matters

Breastfeeding can play an especially important role in early-life nutrition. It can benefit children’s future school performance and economic prospects in later life, as well as the mother’s health.

Health authorities across the world endorse the World Health Organization’s (WHO) recommendation that newborns should where possible exclusively breastfeed from the first hour of life until six months of age, and thereafter receive safe and nutritious foods with continued breastfeeding up to two years of age or beyond.

Despite this, our recent study shows that global commercial milk formula sales are booming. Between 2005 and 2019, world milk formula sales more than doubled from 3.5kg to 7.4kg per child. Total sales grew from 1 million tonnes to 2.1 million tonnes.

This growth in sales was seen in all types of formula, including “standard” formula for infants (0-6 months), “follow-up” formula (7-12 months), toddler milks (13-36 months), and so-called “specialised” formulas. So more children from a wider range of age groups are consuming formula.

Rapid growth has occurred in many highly-populated countries, including the Middle East, north Africa, eastern Europe, central Asia, and parts of Latin America. The most remarkable growth has been in east and south-east Asia. China, in particular, accounted for only 14% of global formula sales in 2005 – but now accounts for 33% of all sales.

In south Asia and west and central Africa, the amount sold to each customer remains low and show no signs of growth. In Europe and North America, although per customer sales volumes remain high, they plateaued or slightly decreased between 2005-2019.

Infant formula sales have doubled between 2005 and 2019. 279photo Studio/ Shutterstock

Behind the sales ‘boom’

There are medical reasons for using safe and adequate breastmilk substitutes. And some women find continuing breastfeeding difficult depending on their circumstances, and may use formula as an alternative or complement to breastfeeding. Our study also shows decisions and practices around formula use can be strongly shaped by wider societal forces, such as commercial marketing, rather than individual choice.

It’s known that milk formula sales increase as countries become richer and more urbanised, and as more mothers enter into formal employment. Asia’s formula sales boom may be partly explained by millions of women entering the paid workforce, especially in the region’s vast manufacturing zones.

Millions of women worldwide also lack adequate paid maternity leave and social protection. This means the decision to formula feed may only be done out of necessity, to avoid losing employment and income. We also know that many hospitals and healthcare settings aren’t equipped to help women establish breastfeeding, with few maternal and newborn care facilities worldwide meeting standards of care for breastfeeding mothers and newborns.

Commercial factors are also important. Just five companies control 57% of the global formula milk industry, worth US$56.6 billion (£42.5 billion) The industry spends an estimated US$5 billion on marketing every year, which powerfully shapes social norms about feeding babies and children.

Marketing messages can portray formula as modern, scientific and comparable or superior to breastmilk. The growth of social media enables companies to target mothers with personalised product offerings and ads.

Hospitals are a key marketing channel, too. Companies often engage health professionals to promote formula feeding. In many countries, health professionals are directly compensated to promote formula. But more commonly, companies influence health professionals indirectly by sponsoring their associations, conferences and education.

Companies cross-promote products by using the same packaging. ValeStock/ Shutterstock

Companies also cross-promote their entire product range of follow-up and toddler milks by using packing and labelling that resembles standard infant formula. This allows companies to get around the stricter prohibitions on infant formula marketing.

Marketing regulations are also important. The fact that formula sales are booming in China but have flat-lined at low levels in India partly reflects contrasting regulatory environments – with regulations on marketing being stricter and more comprehensive in India.

Despite an international code to stop aggressive and inappropriate marketing of breast-milk substitutes, most governments haven’t fully incorporated it into law. And even when laws exist, marketing violations by formula companies often go unpunished. The formula industry has also been able to lobby against any strengthening of regulation, partly by promoting their own – much weaker – corporate policies on marketing.

Health concerns

Breastmilk and breastfeeding where it is possible has numerous advantages over formula and bottle feeding – which is why the growth of formula sales is concerning.

Breastfeeding has been shown to reduce the likelihood of children developing infections, and reduces a child’s risk of developing chronic disease like obesity and diabetes later in life. Breastfeeding is also associated with lower risk of developing breast and cervical cancer, or diabetes among mothers.

Rising consumption of formula milk by toddlers and young children is also a worry, as these products are often ultra-processed, expensive, loaded with sugar and can introduce poor dietary habits. Their increased use could further contribute to increases of overweight and obese children globally.

Formula isn’t a sterile product and can be dangerous when prepared in unhygienic conditions, or when over-diluted or over-concentrated. It lacks the immune-boosting and other important elements of breastmilk, further increasing the risk of malnutrition and infectious illness. As a result, universal breastfeeding in place of formula use could prevent an estimated 823,000 child deaths every year (mainly in low- and middle-income countries), including 595,000 deaths from diarrhoea and pneumonia, and an estimated 20,000 maternal deaths from breast cancer (mainly in high income countries).

The global surge in formula sales is clearly a problem for global health. Given the power of the corporate milk formula industry to influence behaviour and understanding, more needs to be done to ensure that all mothers and children are protected from inappropriate promotion, and that they are enabled to breastfeed as long as they want to. This means strengthening laws that ban harmful marketing practices, expanding access to paid maternity leave, and ensuring that all healthcare facilities meet global standards.

David McCoy, Professor of Global Public Health, Queen Mary University of London; Julie P. Smith, Honorary Associate Professor, Australian National University, and Phillip Baker, Research Fellow, Institute for Physical Activity and Nutrition, Deakin University, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

sb admin Mon, 12/07/2020 - 18:21

Categories

Social Sciences

Greenland Could Lose Ice Faster Than Any Century Since The Last Ice Age Ended

sb admin — Wed, 30 Sep 2020 18:38:02 +0000

Greenland Could Lose Ice Faster Than Any Century Since The Last Ice Age Ended

A new estimate using sheet modeling finds that Greenland's rate of ice loss this century could outpace that of any century over the past 12,000 years, when the last Ice Age ended.

Scientists used reconstructions of ancient climate to drive the model, and validated the model against real-world measurements of the ice sheet's contemporary and ancient size.

The study brought together climate modelers, ice core scientists, remote sensing experts and paleoclimate researchers. The team used an ice sheet model to simulate changes to the southwestern sector of the Greenland Ice Sheet, starting from the beginning of the Holocene epoch 12,000 years ago and extending forward 80 years to 2100. Data came from ice cores to create maps of temperatures and precipitation in the study region that were used to drive the ice sheet model simulations up to the year 1850 while other published climate data were used to drive the simulations after that date.

Infographic describing the study's findings. Image: Bob Wilder / University at Buffalo

Scientists tested the model's accuracy by comparing results of the model's simulations to historical measurements. The modeled results matched up well with data tied to actual measurements of the ice sheet made by satellites and aerial surveys in recent decades, and with field work identifying the ice sheet's ancient boundaries.

"We built an extremely detailed geologic history of how the margin of the southwestern Greenland Ice Sheet moved through time by measuring beryllium-10 in boulders that sit on moraines," says co-author Nicolás Young, PhD, associate research professor at LDEO. "Moraines are large piles of debris that you can find on the landscape that mark the former edge of an ice sheet or glacier. A beryllium-10 measurement tells you how long that boulder and moraine have been sitting there, and therefore tells you when the ice sheet was at that exact spot and deposited that boulder. Amazingly, the model reproduced the geologic reconstruction really well. This gave us confidence that the ice sheet model was performing well and giving us meaningful results. You can model anything you want and your model will always spit out an answer, but we need some way to determine if the model is doing a good job."

Though the project focused on southwestern Greenland, research shows that changes in the rates of ice loss there tend to correspond tightly with changes across the entire ice sheet.

sb admin Wed, 09/30/2020 - 14:38

Categories

Physical Sciences

Fork-Tailed Flycatchers Make Sounds With Their Feathers in Different Accents

sb admin — Thu, 24 Sep 2020 14:46:18 +0000

Fork-Tailed Flycatchers Make Sounds With Their Feathers in Different Accents

(Inside Science) -- The fork-tailed flycatcher whistles with its wings in two different accents, potentially more evidence this bird is splitting into two species, a new study finds.

Birds are known for the songs they can sing, but dozens of species also use their feathers to generate sounds. For instance, peacocks can rattle their quills together, and the crested pigeon's wings whistle when they fly.

In the new study, researchers investigated fork-tailed flycatchers -- 1-ounce birds found throughout the Americas that resemble black-and-gray swallows. The males sport foot-long scissor-shaped tails as ornaments to help attract mates, and they also spread these giant feathers to help turn sharply while hunting by using the plumes as air brakes, said study lead author Valentina Gómez-Bahamón, an evolutionary biologist at the Field Museum in Chicago.

When these birds fly -- sometimes as fast as 65 miles per hour -- they produce a high-pitched trill. Males often fly quickly when they fight each other during mating season, Gómez-Bahamón noted. The birds also fly quickly when fighting off intruders near their nests.

The scientists studied two known subspecies of fork-tailed flycatchers: a migratory one that breeds in the southern part of South America but spends winter closer to the equator, and a nonmigratory one that spends the whole year in the northern part of the continent.

The scientists first captured the birds with "mist nets" -- fine webbing stretched between two poles like a volleyball net -- and recorded audio and video of them as they flew away after they were released. The researchers also set up a taxidermy hawk in a field with a hidden camera, and when the fork-tailed flycatchers swooped in to attack, the researchers recorded how the flycatchers’ feathers moved and what sounds they made. The whole project took three years.

"Recording a fast-flying fighting bird is really hard," Gómez-Bahamón said. "It took many attempts."

The audio and video footage, as well as experiments with fork-tailed flycatcher plumes in a wind tunnel, revealed the birds create these trills with fluttering feathers. Airflow causes these plumes to vibrate with short repetitive whistles, much like the sounds one can whistle using a blade of grass.

Gómez-Bahamón and her colleagues discovered the migratory subspecies made higher-pitched trills with their feathers than their nonmigratory cousins.

The migrating males possess wing feathers with skinnier tips than those of their homebody brethren. These may have evolved to make it easier to fly longer distances. The researchers suggested a group of migratory fork-tailed flycatchers ceased to be migratory, and as their wing feathers thickened because they no longer made long journeys, they ended up sounding different from those of their migratory relatives.

"This is super-challenging work -- these birds are really aerial, and they're not tame," said evolutionary ornithologist Richard Prum at Yale University, who did not take part in this research. "I was amazed at the detail of the analysis they were capable of doing."

Aside from escapes and fights, males of both subspecies trill with their wings in the early morning when it is still dark, likely as displays to females, Gómez-Bahamón said. The birds sing songs, are quiet for a moment, and then perform a short flight where one can hear the fluttering.

Since wing fluttering may help the birds communicate during mating season, Gómez-Bahamón and her colleagues suggest the feather “accents” they found may help further drive the subspecies apart. Eventually, the two types of flycatchers may evolve into fully separate species that cannot interbreed with one another. "Differences in migratory behavior can cascade to other behavioral traits," Gómez-Bahamón said.

Future research will investigate whether related species display similar behavior. The scientists will also explore whether female fork-tailed flycatchers prefer sounds from males of their subspecies, Gómez-Bahamón said. Ornithologist Juan Ignacio Areta at the Institute of Bio and Geosciences of Northwest Argentina, who did not participate in this study, wonders how preventing the birds from making feather trills might influence mate choice. "Answering these exciting questions is difficult, and requires a lot of carefully designed field experiments," he said.

The scientists detailed their findings Sept. 22 in the journal Integrative and Comparative Biology.

Charles Q. Choi is a science reporter who has written for Scientific American, The New York Times, Wired, Science, Nature, and National Geographic News, among others. Reprinted with permission from Inside Science, an editorially independent news product of the American Institute of Physics, a nonprofit organization dedicated to advancing, promoting and serving the physical sciences.

sb admin Thu, 09/24/2020 - 10:46

Categories

Education

Should A Doctor Prescribe A Walk In The Park?

sb admin — Fri, 24 Jul 2020 19:39:42 +0000

Should A Doctor Prescribe A Walk In The Park?

Has your doctor recommended you go for regular jogs in the park, countryside walks, community food growing sessions, or some other nature-based activity? These so-called “green prescriptions” are typically given alongside conventional therapies and have existed in various forms for a number of years.

In recognition of the potential health benefits of green prescriptions, the UK government has just announced a £4 million investment in a two-year pilot as part of its post-COVID-19 recovery plan, with plans to scale up in the future.

There is increasing evidence of the benefits of contact with nature, and the World Health Organization has identified ten ways in which nature impacts positively on our physical and mental health. When parks and other greenspaces are accessible and inclusive they can promote physical activity, psychological relaxation and social cohesion.

There is even evidence to suggest that contact with microbes in the environment can “train” our immune systems and reinforce the microbial communities on our skin, and in our airways and guts. These “microbiomes” could play a role in how our bodies respond to infectious diseases such as COVID-19 and to secondary infections. Microbes from the environment could also potentially supplement our bodies with fatty acids such as butyrate, which are linked to reduced inflammation and may promote mental health.

Green prescriptions therefore have huge potential. But if they are to work, they need to be seen as the start of a much more holistic mode of health and social care delivery: part of a post-COVID “new normal”. This would chime strongly both with the renewed appreciation of nature and the surge in community mobilization and action we saw under the lockdown.

This needs to go beyond simply substituting green for conventional prescriptions. Instead we should provide greener, more natural settings and practices for health, social care, education, transport and active travel. A good example is the GoGoGreen project at a primary school we have worked with in Sheffield. There, greening a school playground not only created a barrier against air pollution from vehicle emissions but also provided multiple other benefits to the school community and started a conversation about cleaner modes of travel.

Green prescribing cannot be seen as a low-cost alternative to conventional treatments. To be effective it still demands investment and resources. The two year pilot is welcome, but if it is to be successful in the long-run the government must make a firm commitment to scaling-up while also addressing systemic issues such as social inequality. All this will take time, and if this holistic approach is not adopted then people in crisis with more immediate priorities will be less likely to go on that prescribed walk in the woods.

Our own research on improving wellbeing through urban nature in Sheffield confirms that people in more deprived communities, with poorer health and shorter life expectancies, don’t have the same levels of access to high quality, well-maintained greenspaces. These are the people that arguably most need green prescriptions, but if they don’t have the basic access then those prescriptions are unlikely to be effective. What’s more, many doctors are not aware of green prescribing, nor do they have a firm understanding of the benefits or know how to get involved.

Our research also reveals that context is critical and green prescriptions need to be rooted in their local area and closely related to the people and places who are going to use them. A wealthy white pensioner in a rural area is likely to have very different experience of and access to nature compared with a young working class person of color in an inner city. A formulaic top-down approach is unlikely to work for both these people.

Recommendations

To sum up, this is what we need to make green prescriptions a success.

They have to be part of a systemic approach to incorporating nature-based interventions and nature-based thinking in urban infrastructure and service provision.

The prescribing process needs to be made easy, for doctors, social care professionals and patients. GPs often lack time and resources, while patients may lack motivation and confidence, or have little previous positive experiences of nature.

Green prescribing also needs to be seen as one part of a holistic health-promotion strategy based on a planetary health perspective. In order to care for ourselves, we also need to care for our environments.

Finally, we need new ways of working with local organisations and communities to understand what’s needed in local contexts, and to build skills and capacity.

By Anna Jorgensen, Chair in Urban Natural Environments, Health and Wellbeing, University of Sheffield and Jake M. Robinson, PhD Researcher, Department of Landscape, University of Sheffield. Jorgensen receives funding from the British Academy and the European Commission. Robinson receives funding from the Economic and Social Research Council (ESRC). He is affiliated with inVIVO Planetary Health, the Healthy Urban Microbiome Initiative and Greener Practice. This article is republished from The Conversation under a Creative Commons license. Read the original article.

sb admin Fri, 07/24/2020 - 15:39

Categories

Medicine

Opportunity Costs And Why Fireworks Complaints Are Up This Year

sb admin — Tue, 30 Jun 2020 16:17:46 +0000

Opportunity Costs And Why Fireworks Complaints Are Up This Year

The number of fireworks being lit off at night is out of control this year.

While people often light off fireworks close to the Fourth of July, this year fireworks have been lit in large numbers starting weeks earlier. New York City had a 4,000% increase in fireworks complaints in the first two weeks of June compared with last year. This prompted Mayor Bill de Blasio to vow a crackdown on illegal fireworks.

Complaints about fireworks are not confined to just New York City, but in cities across the country like San Francisco, Denver, Harrisburg, Albuquerque, Providence and many other places. This has led to a rise in conspiracy theories, including one that the nightly noise is an elaborate government plot to create confusion in neighborhoods.

I am an economist who has spoken and written about fireworks for years. After hearing a constant barrage nightly for weeks, I began wondering why so many people are lighting off fireworks this year.

It isn’t economics

There are two possible economic reasons behind an increase in fireworks usage: falling prices or increased supply. However, neither of these is the culprit behind the increase in fireworks usage this year.

The vast majority of the fireworks individuals shoot off in the U.S. are manufactured overseas, mainly in China. Each shipment of fireworks brought into the U.S. includes a detailed invoice that shows the quantity and price the importer paid.

Price data for the first four months of 2020 show importers paid an average of US$2.63 per kilogram for fireworks from China. A year earlier, importers paid an average of $2.60 per kilogram. This means prices rose slightly from 2019 to 2020, eliminating the falling price argument.

Increased supply is also not the reason. In a typical year there are two holidays with widespread firework usage; New Year’s Eve and the Fourth of July.

Deliveries in 2020 are an exception to this pattern. Because of the coronavirus, the U.S. imported very few fireworks in March. During the first four months of 2020 the U.S. imported 9 million kilograms of fireworks from China. While this seems like a large number, it is one-third less than a year earlier.

Fireworks are much more common around holidays like New Year’s Eve. Tayfun Coskun/Anadolu Agency via Getty Images

Nor is it legal reform

Another potential reason could be changes in laws.

Most major dense cities like New York, Chicago and San Francisco ban fireworks.

However, if neighboring jurisdictions have loosened their rules, then people can easily drive outside the city to purchase fireworks.

There has been a steady reduction in state prohibitions against individuals using fireworks. Today only one state, Massachusetts, completely prohibits individuals from owning and using any type of fireworks. All the rest allow them in some form.

However, the most recent two states to allow consumers to shoot off fireworks are New Jersey in 2017 and Delaware in 2018. Since most states relaxed prohibitions against fireworks more than two years ago, recent rule changes also cannot be behind the increase.

The most likely culprit

To find the real reason, it helps to consider that millions of Americans have been locked down in their homes and apartments for months. As an employee at a fireworks store in Stroudsburg, Pennsylvania, put it, “People are bored. They just want to blow stuff up.”

While this argument is understandable, I think the most likely reason is even simpler. And it has a lot to do with opportunity costs, something economists spend a lot of time thinking about.

Opportunity costs put a dollar value on what else a person could do with their time. For example, before the pandemic, I had many choices at night. I could work, go out with friends, watch television or see a movie in the theater.

By shutting down restaurants, theaters, bars and other venues, COVID-19 has dramatically reduced my choices.

The pandemic has also thrown millions out of work. Many people who would normally be working at night are not. This means the opportunity cost for using fireworks is exceptionally low compared with before, since there are so few opportunities to socialize, be entertained or work.

Beyond lower opportunity costs for fireworks users, there are many unemployed people who are now looking for opportunities to earn money. Buying fireworks in a rural area like northern Pennsylvania and selling them at higher prices in a city that bans their sale, such as New York City, can be easy and profitable.

So few arrests are made for fireworks that the FBI, which tracks problems like moonshining and polygamy on its detailed list of offenses, does not give it a category.

Idle hands

Fireworks are dangerous. While few people die each year from using them, the latest figures for 2019 show that fireworks hurt about 10,000 people per year in the U.S.

However, massive unemployment caused by COVID-19 is also dangerous.

There is an old quote that idle hands lead to mischief. In this case, idle people lead to large amounts of illegal firework usage.

My belief is that once the millions of unemployed people in the U.S. go back to work, the number of illegal fireworks shot off will rapidly decrease and will once again be limited to the times around New Year’s Eve and the Fourth of July.

Top image: Fireworks light up the sky over New York City in 2019. Gary Hershorn/Getty Images

By Jay L. Zagorsky, Senior Lecturer, Questrom School of Business, Boston University. This article is republished from The Conversation under a Creative Commons license. Read the original article.

sb admin Tue, 06/30/2020 - 12:17

Categories

Brain and Behavior