Showing posts with label and. Show all posts
Showing posts with label and. Show all posts
Thursday, December 5, 2024
The United States is paralyzed...and it's not going to get any better
Saturday, November 30, 2024
Prince Harry and Meghan Markle's Christmas wish they know will never happen
The Duke and Duchess of Sussex are expected to spend Christmas in Montecito with their two children and Meghan Markle's mum.
Prince Harry and Meghan Markle reportedly have one Christmas wish (Image: Stephen Pond/Getty Images)
Prince Harry and Meghan Markle are likely to have begun finalising their Christmas plans, which will most likely see the couple and their two children stay in California for the festive season.
While they have not spoken outright about how they will spend the big day next month, it is believed the duke, 40, and duchess, 43, will be at their Montecito home with Meghan’s mum Doria, alongside their children Prince Archie, five, and Princess Lilibet, three.
n a recent chat with a fashion magazine, Meghan revealed how she loved the holidays, especially as the children were now old enough to understand what was going on.
However, while the family are set to have a fun day, there is one Christmas wish the couple - who quit life as senior royals in 2020 - reportedly share that they know can never happen now.
A source exclusively told OK! Magazine: “They both really wish that they could have all their families together and have a huge Christmas but they know that will never happen. So they have to make new memories and traditions with their children and those close to them.”
This year marks the sixth year Prince Harry has not been with his own side of the family for the big day, with the prince having previously spent the special occasion at Sandringham along with the rest of the Royal Family.
However, this has not happened since 2018, the same year he married Meghan Markle in a star-studded Windsor ceremony.
Saturday, July 11, 2020
The best (and worst) materials for masks
The best (and worst) materials for masks
It's intuitive and scientifically shown that wearing a face covering can help reduce the spread of the novel coronavirus that causes COVID-19. But not all masks are created equal, according to new University of Arizona-led research.
Amanda Wilson, an environmental health sciences doctoral candidate in the Department of Community, Environment and Policy in the Mel and Enid Zuckerman College of Public Health, is lead author on a recent study published in the Journal of Hospital Infection that assessed the ability of a variety of nontraditional mask materials to protect a person from infection after 30 seconds and after 20 minutes of exposure in a highly contaminated environment.
When the researchers compared wearing masks to wearing no protection during 20-minute and 30-second exposures to the virus, they found that infection risks were reduced by 24-94% or by 44-99% depending on the mask and exposure duration. Risk reduction decreased as exposure duration increased, they found.
"N99 masks, which are even more efficient at filtering airborne particles than N95 masks, are obviously one of the best options for blocking the virus, as they can reduce average risk by 94-99% for 20-minute and 30-second exposures, but they can be hard to come by, and there are ethical considerations such as leaving those available for medical professionals," Wilson said.
The next best options, according to the research, are N95 and surgical masks and, perhaps surprisingly, vacuum cleaner filters, which can be inserted into filter pockets in cloth masks. The vacuum filters reduced infection risk by 83% for a 30-second exposure and 58% for a 20-minute exposure. Of the other nontraditional materials evaluated by the researchers, tea towels, cotton-blend fabrics and antimicrobial pillowcases were the next best for protection.
Scarves, which reduced infection risk by 44% after 30 seconds and 24% after 20 minutes, and similarly effective cotton t-shirts are only slightly better than wearing no mask at all, they found.
"We knew that masks work, but we wanted to know how well and compare different materials' effects on health outcomes," said Wilson, who specializes in quantitative microbial risk assessment.
Wilson and her team collected data from various studies of mask efficacy and created a computer model to simulate infection risk, taking various factors into consideration.
"One big component of risk is how long you're exposed. We compared risk of infection at both 30 seconds and 20 minutes in a highly contaminated environment," she said.
Other conditions that impact risk of infection are the number of people around you and their distance from you, she said.
The size of virus-transporting droplets from sneezes, coughs or even speech is also a very important factor. Larger, heavier droplets carrying the virus drop out of the air faster than smaller, lighter ones. That's one reason distance helps reduce exposure.
"Aerosol size can also be affected by humidity," Wilson said. "If the air is drier, then aerosols become smaller faster. If humidity is higher, then aerosols will stay larger for a longer period of time, dropping out faster. That might sound good at first, but then those aerosols fall on surfaces, and that object becomes another potential exposure route."
The study also showed that the more time a person spends in an environment where the virus is present, the less effective a mask becomes.
"That doesn't mean take your mask off after 20 minutes," Wilson said, "but it does mean that a mask can't reduce your risk to zero. Don't go to a bar for four hours and think you're risk free because you're wearing a mask. Stay home as much as possible, wash your hands often, wear a mask when you're out and don't touch your face."
Masks protect the wearer and others in a number of different ways. Wilson said there are two "intuitive ways" that masks filter larger aerosols: mechanical interception and inertial impaction.
"The denser the fibers of a material, the better it is at filtering. That's why higher thread counts lead to higher efficacy. There's just more to block the virus," she said. "But some masks (such as those made from silk) also have electrostatic properties, which can attract smaller particles and keep them from passing through the mask as well."
The model developed by Wilson and her colleagues included parameters such as inhalation rate -- the volume of air inhaled over time -- and virus concentration in the air.
"We took a lot of research data, put it into a mathematical model and related those data points to each other," Wilson said. "For example, if we know people's inhalation rates vary by this much and know this much virus is in the air and these materials offer this much efficiency in terms of filtration, what does that mean for infection risk? We provide a range, in part, because everyone is different, such as in how much air we breathe over time."
Wilson also said it's important for a mask to have a good seal that pinches at nose, and she noted that people shouldn't wear a mask beneath the nose or tuck it under the chin when not in use.
"Proper use of masks is so important," Wilson said. "Also, we were focusing on masks protecting the wearer, but they're most important to protect others around you if you're infected. If you put less virus out into the air, you're creating a less contaminated environment around you. As our model shows, the amount of infectious virus you're exposed to has a big impact on your infection risk and the potential for others' masks to protect them as well."
Story Source:
Materials provided by University of Arizona. Original written by Mikayla Mace. Note: Content may be edited for style and length.
Journal Reference:
- Amanda M. Wilson, Sarah E. Abney, Marco-Felipe King, Mark H. Weir, Martín López-García, Jonathan D. Sexton, Stephanie J. Dancer, Jessica Proctor, Catherine J. Noakes, Kelly A. Reynolds. COVID-19 and non-traditional mask use: How do various materials compare in reducing the infection risk for mask wearers? Journal of Hospital Infection, 2020; DOI: 10.1016/j.jhin.2020.05.036
Receptor makes mice strong and slim
Mouse on exercise wheel (stock image).
Increasing abdominal girth and shrinking muscles are two common side effects of aging. Researchers at the University of Bonn have discovered a receptor in mice that regulates both effects. Experiments with human cell cultures suggest that the corresponding signaling pathways might also exist in humans. The study, which also involved researchers from Spain, Finland, Belgium, Denmark and the USA, has now been published in the journal Cell Metabolism.
On their surface, cells carry numerous different "antennas," called receptors, which can receive specific signal molecules. These then trigger a specific reaction in the cell. One of these antennas is the A2B receptor. The surfaces of some cells are virtually teeming with it, for example in the so-called brown adipose tissue. Brown adipose tissue, unlike its white-colored counterpart, is not used to store fat. Instead, it burns fat and thereby generates heat.
"In our publication we took a closer look at the A2B receptors in brown adipose tissue," explains Prof. Dr. Alexander Pfeifer from the Institute of Pharmacology and Toxicology at the University Hospital Bonn. "In the course of this we discovered an interesting association: The more A2B a mouse produces, the more heat it generates." Which means the A2B antennas somehow seem to increase the activity of the brown fat cells. But a second observation was even more exciting: Despite their increased fat burning, the animals weigh hardly less than mice with fewer receptors. "They are slimmer, but at the same time have more muscles," explains Pfeifer.
Muscles like a young mouse
In fact, the researchers were able to show that the muscle cells of mice also carry the A2B receptor. When this is stimulated by a small molecule agonist, muscle growth in the rodents is increased. "The receptor regulates both fat burning and muscle development," emphasizes Pfeifer's colleague Dr. Thorsten Gnad, the lead author of the study.
As they age, mice increasingly lose muscle mass -- similar to humans. And just like us, they also tend to gain a lot of fat around the hips over the years. However, if they receive the agonist that activates the A2B receptor, these aging effects are inhibited: Their oxygen consumption (an indicator of energy dissipation) increases by almost half; moreover, after four weeks of treatment they have as much muscle mass as a young animal. "A2B activation can therefore reverse both aging effects to a certain extent," explains Gnad.
In order to see whether the results were also meaningful for humans, the researchers examined human cell cultures and tissue samples. They found that in people with a large number of A2B receptors, the brown adipose tissue works at a higher rate. At the same time, their muscle cells consume more energy, which may indicate that they are also more active and may be more likely to be regenerated.
"Obesity is a growing problem worldwide," emphasizes Prof. Pfeifer. "Every extra pound not only increases the risk of developing diabetes, but also the risk of high blood pressure, vascular damage and therefore heart attacks and strokes. These problems are further exacerbated by muscles that shrink over the years, as they further reduce the body's energy requirements both at rest and in motion." In addition, poor muscle strength has an immense impact on the everyday life of older people, as they are increasingly restricted in their mobility.
The pharmacologists explain that the prospect of having a receptor on hand that might be able to slow down both of these age-related phenomena is therefore highly exciting. However, further research would first have to show to what extent the human mechanisms actually resemble those in mice. Additionally, there is currently no activator of A2B approved for use in humans. This means that little is known about any side effects of such a treatment. "We found no signs of adverse reactions in mice," says Pfeifer. "However, the meaningfulness of the results is, of course, also limited on this matter."
Gnad emphasizes that the success of the study is also the result of good cooperation with numerous international partners: "Nowadays, it is almost impossible to work on complex issues comprehensively without such cooperation."
Story Source:
Materials provided by University of Bonn. Note: Content may be edited for style and length.
Journal Reference:
- Thorsten Gnad, Gemma Navarro, Minna Lahesmaa, Laia Reverte-Salisa, Francesca Copperi, Arnau Cordomi, Jennifer Naumann, Aileen Hochhäuser, Saskia Haufs-Brusberg, Daniela Wenzel, Frank Suhr, Naja Zenius Jespersen, Camilla Scheele, Volodymyr Tsvilovskyy, Christian Brinkmann, Joern Rittweger, Christian Dani, Mathias Kranz, Winnie Deuther-Conrad, Holger K. Eltzschig, Tarja Niemi, Markku Taittonen, Peter Brust, Pirjo Nuutila, Leonardo Pardo, Bernd K. Fleischmann, Matthias Blüher, Rafael Franco, Wilhelm Bloch, Kirsi A. Virtanen, Alexander Pfeifer. Adenosine/A2B Receptor Signaling Ameliorates the Effects of Aging and Counteracts Obesity. Cell Metabolism, 2020; DOI: 10.1016/j.cmet.2020.06.006
Wednesday, May 20, 2020
Dynamic stimulation of the visual cortex allows blind and sighted people to 'see' shapes
allows, and, blind, cortex, Dynamic, live science, news, of, people, science, science news, science news channal, science news headlines, seeDynamic stimulation of the visual cortex allows blind and sighted people to 'see' shapes
For most adults who lose their vision, blindness results from damage to the eyes or optic nerve while the brain remains intact. For decades, researchers have proposed developing a device that could restore sight by bypassing damaged eyes and delivering visual information from a camera directly to the brain. In a paper publishing in the journal Cell on May 14, a team of investigators at Baylor College of Medicine in Houston report that they are one step closer to this goal. They describe an approach in which implanted electrodes are stimulated in a dynamic sequence, essentially "tracing" shapes on the surface of the visual cortex that participants were able to "see."
"When we used electrical stimulation to dynamically trace letters directly on patients' brains, they were able to 'see' the intended letter shapes and could correctly identify different letters," senior author Daniel Yoshor says. "They described seeing glowing spots or lines forming the letters, like skywriting."
Previous attempts to stimulate the visual cortex have been less successful. Earlier methods treated each electrode like a pixel in a visual display, stimulating many of them at the same time. Participants could detect spots of light but found it hard to discern visual objects or forms. "Rather than trying to build shapes from multiple spots of light, we traced outlines," says first author Michael Beauchamp. "Our inspiration for this was the idea of tracing a letter in the palm of someone's hand."
The investigators tested the approach in four sighted people who had electrodes implanted in their brains to monitor epilepsy and two blind people who had electrodes implanted over their visual cortex as part of a study of a visual cortical prosthetic device. Stimulation of multiple electrodes in sequences produced perceptions of shapes that subjects were able to correctly identify as specific letters.
The approach, the researchers say, demonstrates that it could be possible for blind people to regain the ability to detect and recognize visual forms by using technology that inputs visual information directly into the brain, should they wish to. The researchers note, however, that several obstacles must be overcome before this technology could be implemented in clinical practice.
"The primary visual cortex, where the electrodes were implanted, contains half a billion neurons. In this study we stimulated only a small fraction of these neurons with a handful of electrodes," Beauchamp says. "An important next step will be to work with neuroengineers to develop electrode arrays with thousands of electrodes, allowing us to stimulate more precisely. Together with new hardware, improved stimulation algorithms will help realize the dream of delivering useful visual information to blind people."
Story Source:
Materials provided by Cell Press. Note: Content may be edited for style and length.
Journal Reference:
- Michael S. Beauchamp, Denise Oswalt, Ping Sun, Brett L. Foster, John F. Magnotti, Soroush Niketeghad, Nader Pouratian, William H. Bosking, Daniel Yoshor. Dynamic Stimulation of Visual Cortex Produces Form Vision in Sighted and Blind Humans. Cell, 2020; 181 (4): 774 DOI: 10.1016/j.cell.2020.04.033
Loss of smell and taste validated as COVID-19 symptoms in patients with high recovery rate
Loss of smell and taste validated as COVID-19 symptoms in patients with high recovery rate
Loss of smell and taste has been anecdotally linked to COVID-19 infections. In a study published April 12, 2020 in the journal International Forum of Allergy & Rhinology, researchers at UC San Diego Health report the first empirical findings that strongly associate sensory loss with COVID-19, the respiratory disease caused by the novel coronavirus.
"Based on our study, if you have smell and taste loss, you are more than 10 times more likely to have COVID-19 infection than other causes of infection. The most common first sign of a COVID-19 infection remains fever, but fatigue and loss of smell and taste follow as other very common initial symptoms," said Carol Yan, MD, an otolaryngologist and head and neck surgeon at UC San Diego Health. "We know COVID-19 is an extremely contagious virus. This study supports the need to be aware of smell and taste loss as early signs of COVID-19."
Yan and colleagues surveyed 1,480 patients with flu-like symptoms and concerns regarding potential COVID-19 infection who underwent testing at UC San Diego Health from March 3 through March 29, 2020. Within that total, 102 patients tested positive for the virus and 1,378 tested negative. The study included responses from 59 COVID-19-positive patients and 203 COVID-19-negative patients.
Yan said the study demonstrated the high prevalence and unique presentation of certain sensory impairments in patients positive with COVID-19. Of those who reported loss of smell and taste, the loss was typically profound, not mild. But encouragingly, the rate of recovery of smell and taste was high and occurred usually within two to four weeks of infection.
"Our study not only showed that the high incidence of smell and taste is specific to COVID-19 infection, but we fortunately also found that for the majority of people sensory recovery was generally rapid," said Yan. "Among the Covid-19 patients with smell loss, more than 70 percent had reported improvement of smell at the time of survey and of those who hadn't reported improvement, many had only been diagnosed recently."
Sensory return typically matched the timing of disease recovery. Interestingly, the researchers found that persons who reported experiencing a sore throat more often tested negative for COVID-19.
In an effort to decrease risk of virus transmission, UC San Diego Health now includes loss of smell and taste as a screening requirement for visitors and staff, as well as a marker for testing patients who may be positive for the virus.
Other known symptoms of COVID-19 include fever, fatigue, cough and difficulty breathing. Respondents in Yan's study were most often persons with milder forms of COVID-19 infection who did not require hospitalization or intubation. The findings, she said, underline the importance of identifying early or subtle symptoms of COVID-19 infection in people who may be at risk of transmitting the disease as they recuperate within the community.
"It is our hope that with these findings other institutions will follow suit and not only list smell and taste loss as a symptom of COVID-19, but use it as a screening measure for the virus across the world," Yan said.
Co-authors include: Farhoud Faraji, Divya P. Prajapti, Christine E. Boone and Adam S. DeConde, all at UC San Diego.
Story Source:
Materials provided by University of California - San Diego. Original written by Jeanna Vazquez. Note: Content may be edited for style and length.
Journal Reference:
- Carol H. Yan, Farhoud Faraji, Divya P. Prajapati, Christine E. Boone, Adam S DeConde. Association of chemosensory dysfunction and Covid-19 in patients presenting with influenza-like symptoms. International Forum of Allergy & Rhinology, 2020; DOI: 10.1002/alr.22579
Potentially fatal combinations of humidity and heat are emerging across the globe
High temperature on thermometer (stock image).
Most everyone knows that humid heat is harder to handle than the "dry" kind. And recently, some scientists have projected that later in the century, in parts of the tropics and subtropics, warming climate could cause combined heat and humidity to reach levels rarely if ever experienced before by humans. Such conditions would ravage economies, and possibly even surpass the physiological limits of human survival.
According to a new study, the projections are wrong: such conditions are already appearing. The study identifies thousands of previously rare or unprecedented bouts of extreme heat and humidity in Asia, Africa, Australia, South America and North America, including in the U.S. Gulf Coast region. Along the Persian Gulf, researchers spotted more than a dozen recent brief outbreaks surpassing the theoretical human survivability limit. The outbreaks have so far been confined to localized areas and lasted just hours, but they are increasing in frequency and intensity, say the authors. The study appears this week in the journal Science Advances.
"Previous studies projected that this would happen several decades from now, but this shows it's happening right now," said lead author Colin Raymond, who did the research as a PhD. student at Columbia University's Lamont-Doherty Earth Observatory. "The times these events last will increase, and the areas they affect will grow in direct correlation with global warming."
Analyzing data from weather stations from 1979 to 2017, the authors found that extreme heat/humidity combinations doubled over the study period. Repeated incidents appeared in much of India, Bangladesh and Pakistan; northwestern Australia; and along the coasts of the Red Sea and Mexico's Gulf of California. The highest, potentially fatal, readings, were spotted 14 times in the cities of Dhahran/Damman, Saudi Arabia; Doha, Qatar; and Ras Al Khaimah, United Arab Emirates, which have combined populations of over 3 million. Parts of southeast Asia, southern China, subtropical Africa and the Caribbean were also hit.
The southeastern United States saw extreme conditions dozens of times, mainly near the Gulf Coast in east Texas, Louisiana, Mississippi, Alabama and the Florida Panhandle. The worst spots: New Orleans and Biloxi, Miss. Such conditions also reached inland into Arkansas and along the southeastern coastal plain.
Not surprisingly, incidents tended to cluster on coastlines along confined seas, gulfs and straits, where evaporating seawater provides abundant moisture to be sucked up by hot air. In some areas further inland, moisture-laden monsoon winds or wide areas of crop irrigation appear to play the same role.
Prior climate studies failed to recognize most past incidents because climate researchers usually look at averages of heat and humidity measured over large areas and over several hours at a time. Raymond and his colleagues instead drilled directly into hourly data from 7,877 individual weather stations, allowing them to pinpoint shorter-lived bouts affecting smaller areas.
Humidity worsens the effects of heat because humans cool their bodies by sweating; water expelled through the skin removes excess body heat, and when it evaporates, it carries that heat away. The process works nicely in deserts, but less well in humid regions, where the air is already too laden with moisture to take on much more. Evaporation of sweat slows. In the most extreme instances, it could stop. In that case, unless one can retreat to an air-conditioned room, the body's core heats beyond its narrow survivable range, and organs begin to fail. Even a strong, physically fit person resting in the shade with no clothes and unlimited access to drinking water would die within hours.
Meteorologists measure the heat/humidity effect on the so-called "wet bulb" Centigrade scale; in the United States, these readings are often translated into "heat index" or "real-feel" Fahrenheit readings. Prior studies suggest that even the strongest, best-adapted people cannot carry out normal outdoor activities when the wet bulb hits 32 C, equivalent to a heat index of 132 F. Most others would crumble well before that. A reading of 35 -- the peak briefly reached in the Persian Gulf cities -- is considered the theoretical survivability limit. That translates roughly to a heat index of 160 F. (The heat index actually ends at 127 F, so these readings are literally off the charts.) "It's hard to exaggerate the effects of anything that gets into the 30s," said Raymond.
The study found that worldwide, wet-bulb readings approaching or exceeding 30C on the wet bulb have doubled since 1979. The number of readings of 31 -- previously believed to occur only rarely -- totaled around 1,000. Readings of 33 -- previously thought to be almost nonexistent -- totaled around 80.
A heat wave that struck much of the United States last July maxed out at about 30C on the wet bulb, translating into heat indexes approaching 115 F in places; the highest was 122 F, in Baltimore, Md., and a similar wave hit in August. The waves paralyzed communities and led to at least a half-dozen deaths, including those of an air-conditioning technician in Phoenix, Az., and former National Football League lineman Mitch Petrus, who died in Arkansas while working outside.
It was a modest toll; heat-related illnesses already kill more U.S. residents than any other weather-related hazard including cold, hurricanes or floods. An investigation last year by the website InsideClimate News revealed that cases of heat stroke or heat exhaustion among U.S. troops on domestic bases grew 60 percent from 2008 to 2018. Seventeen soldiers died, almost all in the muggy U.S. Southeast. High-humidity heat waves in Russia and Europe, where far fewer people have air conditioning, have killed tens of thousands.
"We may be closer to a real tipping point on this than we think," said Radley Horton, a Lamont-Doherty research scientist and coauthor of the paper. Horton coauthored a 2017 paper projecting that such conditions would not take hold until later in the century.
While air conditioning may blunt the effects in the United States and some other wealthy countries, there are limits. Before the new study, one of the previously highest heat/humidity events ever reported was in the Iranian city of Bandar Mahshahr, which almost reached a 35C wet-bulb reading on July 31, 2015. There were no known deaths; residents reported staying inside air-conditioned vehicles and buildings, and showering after brief sojourns outside. But Horton points out that if people are increasingly forced indoors for longer periods, farming, commerce and other activities could potentially grind to a halt, even in rich nations-a lesson already brought home by the collapse of economies in the face of the novel coronavirus.
In any case, many people in the poorer countries most at risk do not have electricity, never mind air conditioning. There, many rely on subsistence farming requiring daily outdoor heavy labor. These facts could make some of the most affected areas basically uninhabitable, says Horton.
Kristina Dahl, a climatologist at the Union of Concerned Scientists who led a study last year warning of increasing future heat and humidity in the United States, said the new paper shows "how close communities around the world are to the limits." She added that some localities may already be seeing conditions worse than the study suggests, because weather stations do not necessarily pick up hot spots in dense city neighborhoods built with heat-trapping concrete and pavement.
Steven Sherwood, a climatologist at the Australia's University of New South Wales, said, "These measurements imply that some areas of Earth are much closer than expected to attaining sustained intolerable heat. It was previously believed we had a much larger margin of safety."
The study was coauthored by Tom Matthews, a lecturer in climate science at Loughborough University in the United Kingdom. Colin Raymond is now a postdoctoral researcher at NASA's Jet Propulsion Laboratory.
Story Source:
Materials provided by Earth Institute at Columbia University. Original written by Kevin Krajick. Note: Content may be edited for style and length.
Journal Reference:
- Colin Raymond, Tom Matthews, Radley M. Horton. The emergence of heat and humidity too severe for human tolerance. Science Advances, 2020; 6 (19): eaaw1838 DOI: 10.1126/sciadv.aaw1838
Monday, May 18, 2020
Potentially fatal combinations of humidity and heat are emerging across the globe
Potentially fatal combinations of humidity and heat are emerging across the globe
Most everyone knows that humid heat is harder to handle than the "dry" kind. And recently, some scientists have projected that later in the century, in parts of the tropics and subtropics, warming climate could cause combined heat and humidity to reach levels rarely if ever experienced before by humans. Such conditions would ravage economies, and possibly even surpass the physiological limits of human survival.
According to a new study, the projections are wrong: such conditions are already appearing. The study identifies thousands of previously rare or unprecedented bouts of extreme heat and humidity in Asia, Africa, Australia, South America and North America, including in the U.S. Gulf Coast region. Along the Persian Gulf, researchers spotted more than a dozen recent brief outbreaks surpassing the theoretical human survivability limit. The outbreaks have so far been confined to localized areas and lasted just hours, but they are increasing in frequency and intensity, say the authors. The study appears this week in the journal Science Advances.
"Previous studies projected that this would happen several decades from now, but this shows it's happening right now," said lead author Colin Raymond, who did the research as a PhD. student at Columbia University's Lamont-Doherty Earth Observatory. "The times these events last will increase, and the areas they affect will grow in direct correlation with global warming."
Analyzing data from weather stations from 1979 to 2017, the authors found that extreme heat/humidity combinations doubled over the study period. Repeated incidents appeared in much of India, Bangladesh and Pakistan; northwestern Australia; and along the coasts of the Red Sea and Mexico's Gulf of California. The highest, potentially fatal, readings, were spotted 14 times in the cities of Dhahran/Damman, Saudi Arabia; Doha, Qatar; and Ras Al Khaimah, United Arab Emirates, which have combined populations of over 3 million. Parts of southeast Asia, southern China, subtropical Africa and the Caribbean were also hit.
The southeastern United States saw extreme conditions dozens of times, mainly near the Gulf Coast in east Texas, Louisiana, Mississippi, Alabama and the Florida Panhandle. The worst spots: New Orleans and Biloxi, Miss. Such conditions also reached inland into Arkansas and along the southeastern coastal plain.
Not surprisingly, incidents tended to cluster on coastlines along confined seas, gulfs and straits, where evaporating seawater provides abundant moisture to be sucked up by hot air. In some areas further inland, moisture-laden monsoon winds or wide areas of crop irrigation appear to play the same role.
Prior climate studies failed to recognize most past incidents because climate researchers usually look at averages of heat and humidity measured over large areas and over several hours at a time. Raymond and his colleagues instead drilled directly into hourly data from 7,877 individual weather stations, allowing them to pinpoint shorter-lived bouts affecting smaller areas.
Humidity worsens the effects of heat because humans cool their bodies by sweating; water expelled through the skin removes excess body heat, and when it evaporates, it carries that heat away. The process works nicely in deserts, but less well in humid regions, where the air is already too laden with moisture to take on much more. Evaporation of sweat slows. In the most extreme instances, it could stop. In that case, unless one can retreat to an air-conditioned room, the body's core heats beyond its narrow survivable range, and organs begin to fail. Even a strong, physically fit person resting in the shade with no clothes and unlimited access to drinking water would die within hours.
Meteorologists measure the heat/humidity effect on the so-called "wet bulb" Centigrade scale; in the United States, these readings are often translated into "heat index" or "real-feel" Fahrenheit readings. Prior studies suggest that even the strongest, best-adapted people cannot carry out normal outdoor activities when the wet bulb hits 32 C, equivalent to a heat index of 132 F. Most others would crumble well before that. A reading of 35 -- the peak briefly reached in the Persian Gulf cities -- is considered the theoretical survivability limit. That translates roughly to a heat index of 160 F. (The heat index actually ends at 127 F, so these readings are literally off the charts.) "It's hard to exaggerate the effects of anything that gets into the 30s," said Raymond.
The study found that worldwide, wet-bulb readings approaching or exceeding 30C on the wet bulb have doubled since 1979. The number of readings of 31 -- previously believed to occur only rarely -- totaled around 1,000. Readings of 33 -- previously thought to be almost nonexistent -- totaled around 80.
A heat wave that struck much of the United States last July maxed out at about 30C on the wet bulb, translating into heat indexes approaching 115 F in places; the highest was 122 F, in Baltimore, Md., and a similar wave hit in August. The waves paralyzed communities and led to at least a half-dozen deaths, including those of an air-conditioning technician in Phoenix, Az., and former National Football League lineman Mitch Petrus, who died in Arkansas while working outside.
It was a modest toll; heat-related illnesses already kill more U.S. residents than any other weather-related hazard including cold, hurricanes or floods. An investigation last year by the website InsideClimate News revealed that cases of heat stroke or heat exhaustion among U.S. troops on domestic bases grew 60 percent from 2008 to 2018. Seventeen soldiers died, almost all in the muggy U.S. Southeast. High-humidity heat waves in Russia and Europe, where far fewer people have air conditioning, have killed tens of thousands.
"We may be closer to a real tipping point on this than we think," said Radley Horton, a Lamont-Doherty research scientist and coauthor of the paper. Horton coauthored a 2017 paper projecting that such conditions would not take hold until later in the century.
While air conditioning may blunt the effects in the United States and some other wealthy countries, there are limits. Before the new study, one of the previously highest heat/humidity events ever reported was in the Iranian city of Bandar Mahshahr, which almost reached a 35C wet-bulb reading on July 31, 2015. There were no known deaths; residents reported staying inside air-conditioned vehicles and buildings, and showering after brief sojourns outside. But Horton points out that if people are increasingly forced indoors for longer periods, farming, commerce and other activities could potentially grind to a halt, even in rich nations-a lesson already brought home by the collapse of economies in the face of the novel coronavirus.
In any case, many people in the poorer countries most at risk do not have electricity, never mind air conditioning. There, many rely on subsistence farming requiring daily outdoor heavy labor. These facts could make some of the most affected areas basically uninhabitable, says Horton.
Kristina Dahl, a climatologist at the Union of Concerned Scientists who led a study last year warning of increasing future heat and humidity in the United States, said the new paper shows "how close communities around the world are to the limits." She added that some localities may already be seeing conditions worse than the study suggests, because weather stations do not necessarily pick up hot spots in dense city neighborhoods built with heat-trapping concrete and pavement.
Steven Sherwood, a climatologist at the Australia's University of New South Wales, said, "These measurements imply that some areas of Earth are much closer than expected to attaining sustained intolerable heat. It was previously believed we had a much larger margin of safety."
The study was coauthored by Tom Matthews, a lecturer in climate science at Loughborough University in the United Kingdom. Colin Raymond is now a postdoctoral researcher at NASA's Jet Propulsion Laboratory.
Saturday, February 8, 2020
Eating red meat and processed meat hikes heart disease and death risk, study finds
Processed meats (stock image).
After a controversial study last fall recommending that it was not necessary for people to change their diet in terms of red meat and processed meat, a large, carefully analyzed new study links red and processed meat consumption with slightly higher risk of heart disease and death, according to a new study from Northwestern Medicine and Cornell University.
Eating two servings of red meat, processed meat or poultry -- but not fish -- per week was linked to a 3 to 7% higher risk of cardiovascular disease, the study found. Eating two servings of red meat or processed meat -- but not poultry or fish -- per week was associated with a 3% higher risk of all causes of death.
"It's a small difference, but it's worth trying to reduce red meat and processed meat like pepperoni, bologna and deli meats," said senior study author Norrina Allen, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Red meat consumption also is consistently linked to other health problems like cancer."
"Modifying intake of these animal protein foods may be an important strategy to help reduce the risk of cardiovascular disease and premature death at a population level," said lead study author Victor Zhong, assistant professor of nutritional sciences at Cornell, who did the research when he was a postdoctoral fellow in Allen's lab.
The paper will be published Feb. 3 in JAMA Internal Medicine.
The new findings come on the heels of a controversial meta-analysis published last November that recommended people not reduce the amount of red meat and processed meat they eat. "Everyone interpreted that it was OK to eat red meat, but I don't think that is what the science supports," Allen said.
"Our study shows the link to cardiovascular disease and mortality was robust," Zhong said.
What should we eat?
"Fish, seafood and plant-based sources of protein such as nuts and legumes, including beans and peas, are excellent alternatives to meat and are under-consumed in the U.S.," said study coauthor Linda Van Horn, professor of preventive medicine at Feinberg who also is a member of the 2020 U.S. Dietary Guidelines Advisory committee.
The study found a positive association between poultry intake and cardiovascular disease, but the evidence so far isn't sufficient to make a clear recommendation about poultry intake, Zhong said. Still, fried chicken is not recommended.
The new study pooled together a large diverse sample from six cohorts, included long follow-up data up to three decades, harmonized diet data to reduce heterogeneity, adjusted a comprehensive set of confounders and conducted multiple sensitivity analyses. The study included 29,682 participants (mean age of 53.7 years at baseline, 44.4% men and 30.7% non-white). Diet data were self-reported by participants, who were asked a long list of what they ate for the previous year or month.
Key findings:
- A 3 to 7% higher risk of cardiovascular disease and premature death for people who ate red meat and processed meat two servings a week.
- A 4% higher risk of cardiovascular disease for people who ate two servings per week of poultry, but the evidence so far is not sufficient to make a clear recommendation about poultry intake. And the relationship may be related to the method of cooking the chicken and consumption of the skin rather than the chicken meat itself.
- No association between eating fish and cardiovascular disease or mortality.
Limitations of the study are participants' dietary intake was assessed once, and dietary behaviors may have changed over time. In addition, cooking methods were not considered. Fried chicken, especially deep fat-fried sources that contribute trans-fatty acids, and fried fish intake have been positively linked to chronic diseases, Zhong said.
Other Northwestern authors are Dr. Philip Greenland, Dr. Mercedes R. Carnethon, Dr. Hongyan Ning, Dr. John T. Wilkins and Dr. Donald M. Lloyd-Jones.
The study was funded by National Institutes of Health/National Heart, Lung, and Blood Institute (R21 HL085375), American Heart Association Strategically Focused Research Networks and the Feinberg School of Medicine.
Story Source:
Materials provided by Northwestern University. Original written by Marla Paul. Note: Content may be edited for style and length.
Tuesday, February 4, 2020
'Parentese' helps parents, babies make 'conversation' and boosts language development
Mother talking to baby (stock image).
Used in virtually all of the world's languages, parentese is a speaking style that draws baby's attention. Parents adopt its simple grammar and words, plus its exaggerated sounds, almost without thinking about it.
But if parents knew the way they speak could help baby learn, would they alter their speech?
A new study from the Institute for Learning & Brain Sciences, or I-LABS, at the University of Washington suggests they would, to baby's benefit. Researchers examined how parent coaching about the value of parentese affected adults' use of it with their own infants, and demonstrated that increases in the use of parentese enhanced children's later language skills.
The study, published online Feb. 3 in the Proceedings of the National Academy of Sciences, finds that parents who participated in individual coaching sessions used parentese more often than control-group parents who were not coached, and that coaching produced more parent-child "conversational turns" and increased the child's language skills months later.
"We've known for some time that the use of parentese is associated with improved language outcomes," said Patricia Kuhl, I-LABS co-director and professor of speech and hearing sciences at the UW. "But we didn't know why. We believe parentese makes language learning easier because of its simpler linguistic structure and exaggerated sounds. But this new work suggests a more fundamental reason.
"We now think parentese works because it's a social hook for the baby brain -- its high pitch and slower tempo are socially engaging and invite the baby to respond."
Parentese is not what is often called "baby talk," which is generally a mash-up of silly sounds and nonsense words. Instead, it is fully grammatical speech that involves real words, elongated vowels and exaggerated tones of voice. Spoken directly to the child, it sounds happy and engaged, and helps infants tune in socially to their parents and respond, even if only through babbling.
In a 2018 study, I-LABS researchers tracked use of parentese among adults and their 6-month-old infants, and found that babies whose parents participated in parentese coaching sessions babbled more and produced more words by age 14 months than infants whose parents were not directed in the technique.
The new study focuses on the long-term outcomes of parent coaching and how it led to changes in the parents' language, in parent-child conversation, and eventually, in the child's speech at 18 months.
"We had no idea that parents would respond so positively to information about how their own speech to the child affects the child's language development. Parent coaching gave parents a measurement tool, almost like a Fitbit for parentese, and it worked," said lead author Naja Ferjan Ramírez, a UW assistant professor of linguistics.
To assess child language output, all families in the study were given a lightweight recorder, which the child wore in a specially designed vest during four separate weekends at ages 6, 10, 14 and 18 months. The device recorded both parent and infant speech over the entirety of two consecutive days, so that researchers could measure parents' use of parentese, parent-child conversational turns, as well as infant language production -- either babbling or actual words. Parent coaching sessions occurred at 6, 10 and 14 months.
For the 48 families randomly assigned to receive coaching, the sessions provided guidance and feedback on specific communication strategies, such as using parentese, speaking directly to the child and engaging the child in back-and-forth exchanges known as conversational turns. In reviewing recordings with parents, researchers played back recordings of parents' language behaviors and measured them against research-based targets for child language development. Parents were encouraged to include language as part of daily routines and were given language-interaction tips in the form of cards with "brain building" tips from Vroom, a program of the Bezos Family Foundation.
All parents in the study already used parentese at the beginning of the project, but their use varied greatly, the researchers said. Those in the coaching group learned more about the cognitive and social benefits of parentese, when and how to use it to promote interaction with their child, and the positive effects that parentese could have on their child's language development.
The results show that parent coaching resulted in an increased use of parentese and infant vocalizations that continued to grow after the end of the parent coaching sessions. Between 14- and 18-months, coached families showed a drastic jump in conversational turn-taking and child vocalizations. Children of coached parents produced real words -- such as "banana" or "milk" -- at almost twice the frequency of children whose parents were in the control group. Parent surveys estimated that the children's 18-month vocabulary averaged around 100 words among children of coached families, compared to 60 words among children in the control group.
"We know that language skills in infancy predict subsequent stages in language development, so enhancements in language behaviors in infancy could therefore have cascading effects on speech development over time," said Ferjan Ramírez.
Kuhl added, "Language evolved to facilitate the social communication skills that are essential for survival of the species. In this study, we observe firsthand how parents' language and social engagement can promote baby's initial responsive coos, which become words, and then sentences -- educating infants in the art of human communication."
The study was funded by the Overdeck Family Foundation and UW I-LABS Ready Mind Project. Sarah Roseberry Lytle, outreach and education director at I-LABS, was a co-author.
Story Source:
Materials provided by University of Washington. Original written by Kim Eckart. Note: Content may be edited for style and length.
Saturday, January 25, 2020
Weight loss and health improvements with Mediterranean, fasting & Paleo diets
Weight loss and health improvements with Mediterranean, fasting & Paleo diets
There were some weight loss and health benefits for overweight adults who followed the Mediterranean, Intermittent Fasting and Paleo diets, though adherence to the diets dropped off considerably during the one-year study, new University of Otago research shows.
Intermittent fasting -- whereby participants limit their energy intake to about 25 per cent of their usual diet (500kcal for women and 600kcal for men) on two self-selected days per week, led to slightly more weight loss than the other diets. The Mediterranean diet also improved blood sugar levels.
Co-lead author Dr Melyssa Roy, a Research Fellow in the Department of Medicine, says the amount of weight loss was modest -- on average two to four kilograms for the 250 participants, but for those choosing the fasting or Mediterranean diets, clinically significant improvements in blood pressure were also seen.
The aim of the research was to examine how effective all three diets were in a "real world" setting, where participants self-selected which diet they wished to follow, without any ongoing support from a dietitian.
Dr Roy says the evidence shows that for some people the Mediterranean, fasting or paleo (Paleolithic) diets can be "healthful, beneficial ways to eat."
"This work supports the idea that there isn't a single 'right' diet -- there are a range of options that may suit different people and be effective. In this study, people were given dietary guidelines at the start and then continued with their diets in the real world while living normally. About half of the participants were still following their diets after a year and had experienced improvements in markers of health.
"Like the Mediterranean diet, intermittent fasting and paleo diets can also be valid healthy eating approaches -- the best diet is the one that includes healthy foods and suits the individual."
The Mediterranean diet encouraged consumption of fruit, vegetables, whole-grain breads and cereals, legumes, nuts, seeds and olive oil with moderate amounts of fish, chicken, eggs and diary and red meat once a week or less.
The paleo diet consists of mostly less-processed foods with an emphasis on eating fruit and vegetables, animal proteins, nuts, coconut products and extra-virgin olive oil. While "original" Paleo diets strictly exclude all legumes, dairy and grains, this study used a modified version including some dairy as well as up to one serving daily of legumes and grain-based food.
Co-lead author Dr Michelle Jospe, a Postdoctoral Fellow in the Department of Medicine, says the results showed people found the Mediterranean diet to be the easiest to adhere to.
"Our participants could follow the diet's guidelines more closely than the fasting and paleo diets and were more likely to stay with it after the year, as our retention rates showed."
Most of the 250 participants (54 per cent) chose the fasting diet, while 27 per cent chose the Mediterranean and 18 per cent the paleo. After 12 months, the Mediterranean diet had the best retention rate with 57 per cent of participants continuing, with 54 per cent still fasting and 35 per cent still on the paleo diet.
After 12 months, the average weight loss was 4.0kg for those choosing the fasting diet, 2.8kg on the Mediterranean diet and 1.8kg on the paleo diet.
Reduced systolic blood pressure was observed among those participating in the fasting and Mediterranean diets, together with reduced blood sugar levels in the Mediterranean diet.
Dr Jospe explains participants who said they were still following their diet at 12 months lost even more weight, showing the importance of choosing a diet that is sustainable.
She believes the results of this study are relevant to the thousands of people following self-chosen diets with little supervision and indicates more realistic outcomes.
Story Source:
Materials provided by University of Otago. Note: Content may be edited for style and length.
Subscribe to:
Posts (Atom)