IIf we removed walls, ceilings, street lights, screens and let our senses guide us, we could get up at sunrise and sleep when it sets. Artificial lighting and blackout blinds allow us to choose our waking hours, but is it good for us to go to bed late under the light of electric bulbs and then sleep late? On Sunday, March 26, the clock changes to British Summer Time. That’s why we need to make the most of the extra daylight.
Why is morning light so important?
The body’s 24-hour cycle – its circadian rhythm – is controlled by light.“We evolved in the open,” says Dr Christine Blum, a sleep researcher at the Center for Chronobiology at the University of Basel. “So our biological clock is especially sensitive to daylight.”
This function, sometimes referred to as the circadian pacemaker, is found in suprachiasmatic nucleus (SCN) in the brain’s control center, the hypothalamus.
The most important timestamp of the environment – or timer – SCN achievement ambient light. “We receive information about time in the environment through our eyes,” Bloom says.
According to Blume, the non-image-forming light-sensitive cells in the eye primarily connect our internal biological clock to our environment. “[They are] especially sensitive to short waveswhich we sometimes call blue,” she says.
Morning light, according to Bloom, causes a “phase shift.” It adjusts the internal biological clock, speeding it up a little, helping you get tired more quickly in the evening.
In fact, morning light is so important that there is strong evidence that it powerful antidepressant – sometimes as effective as pharmaceutical antidepressants.
Serotonin, often referred to as the body’s natural antidepressant, is produced when sunlight hits the eyes. The most commonly prescribed antidepressants are designed to increase serotonin levels in the brain. However, these medications can come with numerous side effects, from anxiety to diarrhea to sexual dysfunction.
On the other hand, using daylight to treat depression has no such side effects. Morning Light Therapy has been proven to useful in treatment seasonal affective disorder (SAD), perinatal depression, bipolar depression, eating disorders and attention deficit hyperactivity disorder (ADHD).
In the evening, as the sun approaches the horizon, blue light waves scatter into the atmosphere, while longer, redder light waves reach the earth’s surface. It is at this time that the master biological clock initiates production melatonina hormone that promotes sleep.
In this way, our circadian rhythm aligns our sleep and wakefulness with day and night, creating a healthy restorative cycle that allows for increased daytime activity.
“People often think they’re either larks or owls, but most of us fall somewhere in between.” Photographer: SimpleImages/Getty Images
How daylight can help you sleep
Getting enough natural light throughout the day critical for quality sleep at night – and sleep is essential if you want to function during the day. When you sleep, your brain forms new thought connections and memories are combined. Without sleep, your ability to concentrate, learn, and remember deteriorates.
Is yours the immune system also depends on sleep. While you sleep, it produces protective, infection-fighting antibodies and cytokines. Lack of sleep prevents this defense from being built up, so your body may not be able to resist invaders and it may take longer to recover from illness.
“We have one biological master clock, which I like to think of as the conductor of an orchestra,” Bloom says. “And we have other clocks, for example, in the liver, heart and skin — in virtually every cell in the body.”
These trillions of tiny clocks are our natural timing devices, regulating the physiological functions of the entire body over a period of approximately 24 hours.
So, if you mess up your main watch, you mess up every other day-to-day function as well.
Take, for example, appetite. Have you ever noticed that you feel hungry when you are tired? More and more evidence is emerging linking lack of sleep with weight gain and obesity.
The production of hormones depends on sleep.Two of these hormones these are leptin, which tells your brain that you are full, and ghrelin, the “hunger hormone.” It has been found that sleep deprivation reduce leptin and increase ghrelinencouraging you to eat more than you really need.
I’m an owl, should I force myself to get up with the sun?
“People often think they’re either larks or owls, but most of us fall somewhere in between,” Bloom says. The real owls, Blume explains, are those who suffer from “delayed sleep phase syndrome.”
“They can’t fall asleep before 2 am or even later, and for them waking up at 8 am is like waking up at 5 am for everyone else.”
Most of us just have a penchant for owls. We prefer to stay up late and wake up at 8am rather than 6:30am, but it’s pretty easy to retrain our circadian rhythm by limiting light in the evening and going to bed earlier.
“Nature has come up with something that allows us to synchronize with the outside world,” Bloom says. “Our bodies and the world communicate. Your chronotype is the interaction between genetics and exposure to light, i.e. behavior. You can adapt to some extent.”
But I can lie on the weekend, right?
The problem comes during the weekend when we have the freedom to sleep whenever we want. Often we shift our circadian rhythms to a later time, which can lead to sleepy Monday mornings.
“We call this mismatch between social and internal biological rhythms ‘social jet lag,'” Blume says.
Bloom recommends making sure you get plenty of natural light in the morning and avoid artificial light in the evening to speed up your body clock, effectively putting it on a more socially acceptable schedule.
And, Bloom says, it’s important to go out. On a clear summer day, you can easily 100,000 lux (a measure of the intensity of the light level). This is about 200 times the standard lighting you would see indoors.
“Even on a cloudy day, the light outside is much brighter than inside,” Bloom says. “We often underestimate the brightness of daylight.”
Being outdoors brings other benefits as well. Vitamin D – “sunshine vitamin– Produced when sunlight hits the skin. This vitamin helps the body absorb and retain calcium and phosphorus needed to build bones. This was also found to reduce the growth of cancer cells, help control infections and reduce inflammation.
Go for a walk, run or bike ride first thing in the morning and avoid the blue light of screens in the evening – you’ll sleep better at night and feel better.
The world must step back from the brink of climate catastrophe to save the people of the Pacific from annihilation, Samoan Prime Minister urged.
On the eve of an important report by the Intergovernmental Panel on Climate Change, expected to be the scientific “last warning” of the climate emergency, Samoa’s Prime Minister Fiame Naomi Mataafa issued a desperate call to action.
“We are all affected, but the extent of the impact depends on the specific circumstances of the countries. So our low-lying atoll countries are right here, we live with it,” Mataafa said.
“There are already examples of communities in the Pacific, entire communities that have moved to different countries,” she said. “They really have to deal with issues of sovereignty through the loss of land.”
Mataafa warned that all countries will face mounting damage if they do not act now. “This is a collective problem, no one is immune from the effects of climate change,” she said in an interview with the Guardian. “Therefore, it is very important for the global family to adhere to the definitions [to cut greenhouse gas emissions] which have already been made. It seems more immediate to us [in the Pacific] but it still affects all of us.”
Fiame Naomi Mataafa. Photographer: Adrian Dennis/AFP/Getty Images
On Monday, the IPCC will present final summary of their latest global climate science assessment. Known as the ‘summary report’, it is expected to warn that the world has only a few years to make a deep transition to a global low-carbon economy or face catastrophe caused by extreme weather, including sea level rise, extreme heat. devastating droughts, more severe floods and a range of other impacts.
The report also laid out ways to achieve this low-carbon economy and keep global warming within the critical threshold of 1.5°C above pre-industrial levels, above which the IPCC has warned of consequences that would quickly become catastrophic and irreversible.
Mataafa said: “With the work of the IPCC, there is a glimmer of hope that there is a body of evidence that can support the decisions that need to be made. [People in Samoa are] having faith that [this message] endure.”
The IPCC is the world’s leading group of climate scientists, with hundreds of leading authors drawing on the peer-reviewed work of thousands of scientists to produce comprehensive reports spanning thousands of long pages summarizing global knowledge of the crisis.
Over the past two years, the IPCC has published its sixth such assessment since 1988, in three parts from August 2021 to March 2022. This final report, called the Synthesis Report, will summarize previous warnings and present them to governments around the world. .
The IPCC reports take six to eight years to complete, so they will be the last before 2030, when the world may already have passed the 1.5 degree Celsius threshold, unless greenhouse gas emissions are reduced in the next few years.
Professor Emily Schuckburg, director of Cambridge Zero at the University of Cambridge, said: “The science is clearer than ever and once again scientists around the world are reminding us how little time we have left to limit warming to 1.5°C. Even now, at 1.1°C, climate change is deadly.”
Alok Sharma, president of the 2021 UN climate summit Cop26, said governments must respond. “The IPCC reports continue to serve as a wake-up call for world leaders to act much faster if we are to maintain any hope of maintaining 1.5C. While we are seeing some progress, frankly, we are moving too slowly towards decarbonizing our economy and adapting to a changing climate,” he told The Guardian.
He called for more investment. “Finance is key, and the trillions of dollars of climate change that many leaders have been talking about is now critical,” he said.
The Pacific islands are among the countries most at risk, Mataaf said, and have been instrumental in calling for other countries to accept the 1.5-degree Celsius limit.
Consisting of nine small islands in the mid-Pacific Ocean about halfway between New Zealand and Hawaii, Samoa has higher landmass than many of its atoll neighbors. But the country is still facing rising sea levels and more destructive storms.
Mataafa, Samoa’s first female prime minister, attended a Commonwealth Secretariat event in London last week to discuss the role of women in tackling the climate crisis.
An international panel of virus experts said on Thursday they had found genetic data at a market in Wuhan, China that linked the coronavirus to raccoon dogs for sale there, adding evidence that the worst pandemic in a century could have been caused by the virus. an infected animal that has been sold through the illegal wildlife trade.
The genetic data was taken from swabs taken in and around the Huanan Seafood Wholesale Market starting in January 2020, shortly after Chinese authorities closed the market over suspicions that it was linked to a novel virus outbreak. By that time, the animals had already been removed, but the researchers were smearing walls, floors, metal cages and carts that were often used to transport animal cages.
In samples that tested positive for the coronavirus, an international research team found animal genetic material, including a large amount that matched a raccoon dog, three scientists involved in the analysis said.
Mixing the genetic material of the virus and the animal does not prove that the raccoon dog itself was infected. And even if a raccoon dog were infected, it would not be clear that the animal transmitted the virus to humans. Another animal could have transmitted the virus to humans, or someone infected with the virus could have passed the virus to a raccoon dog.
But the analysis did establish that raccoon dogs — furry animals that are related to foxes and known to be able to transmit the coronavirus — deposited genetic signatures in the same place where the genetic material from the virus was left, the three scientists said. This evidence, they say, is consistent with a scenario in which the virus entered humans from a wild animal.
A full report on the findings of the international research team has not yet been published. Their analysis was first reported Atlantic Ocean.
The new data is sure to revive the debate about the origin of the pandemic, even if it does not address the question of how it began.
In recent weeks, the so-called lab leak theory, which claims the coronavirus originated from a research lab in Wuhan, has gained traction thanks to a new intelligence assessment by the U.S. Department of Energy and hearings led by new Republican Chamber leadership.
But genetic data from the market offers some of the most tangible evidence of how the virus could have entered humans from wild animals outside the lab. It also suggests that Chinese scientists have given an incomplete account of the evidence that could fill in the details about how the virus spread in the Huanan market. .
More about the coronavirus pandemic
Jeremy Kamil, a virologist at the Louisiana State University Health Sciences Center at Shreveport, who was not involved in the study, said the results showed “samples from the market that had early Covid lines were contaminated with wild animal DNA reads.”
Dr Kamil said he lacked conclusive evidence that an infected animal caused the pandemic. But, he says, “it really brings out the illegal animal trade in a personal way.”
Chinese scientists released study considering the same market samples in February 2022. This study reported that the samples were positive for coronavirus, but it was assumed that the virus came from infected people who shopped or worked at the market, and not from the animals that were sold there.
At some point, the same researchers, including those affiliated with the Chinese Centers for Disease Control and Prevention, posted raw swab data from the market to GISAID, the international repository for viral genetic sequences. (Attempts to contact Chinese scientists by phone on Thursday were unsuccessful.)
On March 4, Florence Debarre, an evolutionary biologist at the French National Center for Scientific Research, accidentally searched the database for information related to the Huanan market when, she said in an interview, she noticed that more sequences than usual were showing up. first about whether they contained new data, dr. DeBarr put them aside, only to log back in last week to find they had a lot of raw data stored in them.
Virus experts have been waiting for this raw sequence data from the market since they learned of its existence in a February 2022 Chinese report. Debarre said she alerted other scientists, including the leaders of a group that published a number of studies last year pointing to the market as the source.
An international team that included Michael Sparrow, an evolutionary biologist at the University of Arizona; Christian Andersen, virologist at the Scripps Research Institute in California; and Edward Holmes, a biologist at the University of Sydney, began collecting new genetic data last week.
One specimen in particular caught their attention. It was taken from a cart tied to a specific stall in the Huanan Market where Dr. S. Holmes visited in 2014, according to scientists involved in the analysis. This tent, doctor. Holmes found that raccoon dogs were kept in a cage on top of a separate cage with birds, and this is precisely the environment that facilitates the transmission of new viruses.
The research team found that a swab taken from a cart in early 2020 contained virus and raccoon dog genetic material.
“We were able to figure out relatively quickly that at least one of those samples had a lot of raccoon dog nucleic acid, along with virus nucleic acid,” said Steven Goldstein, a virologist at the University of Utah who worked on the study. new analysis. (Nucleic acids are the chemical building blocks that carry genetic information.)
After the international team stumbled upon the new data, they approached the Chinese researchers who uploaded the files to collaborate while respecting the rules of the online repository, the scientists involved in the new analysis said. After that, the sequences disappeared from GISAID.
It is not clear who removed them or why they were removed.
Dr. Debarre said the research team was looking for more data, including some of the market samples that have never been released to the public. “The important thing is that there is even more data,” she said.
Scientists involved in the analysis said some of the samples also contained genetic material from other animals and humans. Angela Rasmussen, a virologist with the Organization for Vaccines and Infectious Diseases at the University of Saskatchewan in Canada who worked on the analysis, said the human genetic material was to be expected given that people shopped and worked there and cases of Covid in humans were reported. were connected to the market.
Dr. Goldstein also warned that “we don’t have an infected animal, and we can’t prove for sure that there was an infected animal in that stall.” The genetic material of the virus is quite stable, he said, so it is not clear exactly when it entered the market. He said the team was still analyzing the data and that it had no intention of releasing its analysis prior to releasing the report.
“But,” he said, “given that the animals that were on the market were not selected at the time, this is the best we can hope for.”
Giant stars can be a prime example of the “live fast, die young” principle. Unlike our own Sun, which will shine for billions of years, more massive stars can burn off their fusion fuel in just a few million years before shedding their outer layers and exploding in supernovae.
NASA this week presented a rare image from the James Webb Space Telescope (JWST) of one of these stellar giants, Wolf-Rayet stars in the last, fleeting stages of their lives. Named WR 124, it lies in the constellation Sagittarius and lies about 15,000 light-years from Earth. The dying star has at least 30 times the mass of our Sun, but it is rapidly contracting, expelling hot gas into the cold vacuum of space.
“We caught it before,” explains Anthony Moffat, a retired astrophysicist who previously observed WR 124 with the Hubble Space Telescope and was not involved in the recent JWST measurements. Moffat has been studying Wolf-Rayet stars for decades. “This is the youngest person I know,” he says. The colorful cloud in the image, somewhat erroneously called a planetary nebula, is only a few thousand years old. Now, “the nebula is hugging the star,” he says. But as time passes, it will bloom outward in the form of expanding shells or rings of gas and dust.
Stars are natural fusion reactors, glowing with the energy released when hydrogen is fused to form helium atoms. Once massive stars burn off all their hydrogen, they begin to convert helium into heavier elements through a more energetic fusion reaction, causing powerful stellar winds. Rushing at speeds of more than 150,000 kilometers per hour, these winds carry the outer layers of the star with them, throwing huge volumes of gas and dust into space.
This gas glows with infrared radiation, the same type of light that JWST detects. Astrophysicists have created an impressive image by combining data from two JWST instruments, a near-infrared camera (NIRCam) and a mid-infrared (MIRI) instrument. The Hubble Space Telescope, which predominantly collects light in the optical range, has taken pictures of WR 124 before, but the JWST observations show the star’s growing nebula in stunning new detail.
“Personally, the most exciting part of this image is that we are capturing a rare phenomenon, i.e. a Wolf-Rayet star, at a level of detail that can only be achieved with JWST,” says Macarena Garcia Marin, an astrophysicist. The European Space Agency, which works with MIRI.
Only massive stars can go through the Wolf-Rayet phase, and not all of them. Astronomers have calculated that there are only 1,000 Wolf-Rayet stars in our galaxy—about one in every 100 million. The nearest one is about 1,000 light-years away in the star system Gamma Velorum, visible from the Southern Hemisphere. According to Moffat, Wolf-Rayet stars could be a million times brighter than the Sun. “What they lack in numbers, they make up for in light,” he adds.
“This dust is spreading into space and will eventually create planets. And that’s how we got here, really,” NASA astrophysicist Amber Strone said during a panel discussion at the 2023 South by Southwest conference in Austin, Texas, where the image was first unveiled. “I think this is one of the most beautiful concepts in all of astronomy.”
But while we are all made of stardust, there seems to be a lot more to the universe than scientists can explain with a simple cataloging of obvious sources. “It’s always exciting to be in science when our theories don’t match up with our observations — and that’s where we are right now with the dust,” Strawn says. These detailed pictures of the decoupling of a dying star as it forges heavy elements and produces copious amounts of dust could help scientists refine their understanding of this underlying process.
Someday—thousands or even millions of years from now, but essentially tomorrow on a galactic scale—WR 124 will explode in a spectacular supernova. In addition to a large amount of dust and heavy elements, a black hole may remain after the explosion. But physicists don’t have a good way to predict this with certainty. Moffat suggests that the supernova remnant could instead turn into a neutron star, the last stop before the collapsing star reaches the ultimate oblivion of a black hole. Without a glimpse from some observatory that remains for us in the distant future, we may never know what will happen to WR 124. But in any case, its ultimate fate remains the same, written in stars and planets that are still not formed from his generous gift of cosmic dust.
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