Summary:
- OneWeb UK announces completion of space Internet project - Musk's "Starlink" competitor is coming!
- Trace amounts of plastic can cause terrible problems in chicken embryos
- NASA's next group of astronauts on the moon will be more diverse than the last, including people of color and women
- A new study suggests that the Greenland ice sheet is nearing an irreversible melting point
- Studies have found that the Mediterranean diet reduces the risk of dementia
- Why does weight loss fail by dieting? Probably because the brain amplifies the signals of hunger synapses
- OneWeb UK announces completion of space Internet project - Musk's "Starlink" competitor is coming!
London-based OneWeb has launched the last set of 36 satellites needed to provide broadband internet connectivity anywhere on Earth. The 36 satellites were lifted off by Indian LVM3 rockets from the Sri Harikota spaceport in Andhra Pradesh, increasing the total number of OneWeb's satellites in orbit above Earth from 582 to 618. It will take months for the satellites to test and enter the right sky from 450 kilometers above sea level (1,200 kilometers above sea level), but when they are in place, OneWeb will have the ability to provide global communication services.
Unlike its main competitor, Elon Musk's Starlink system, OneWeb doesn't sell broadband connections directly to individual users. Its customers are mainly telecommunications companies that provide such Internet services. They may also use connectivity to supplement or extend the infrastructure of mobile phone networks. As a result, the OneWeb system will require the necessary ground infrastructure to command and control all satellites and connect them to the internet, which will also be fully operational by the end of 2023.
A TYPICAL SERVICE PLAN FOR A ONEWEB USER TERMINAL OR ANTENNA SYSTEM CAN BE 75 MEGABITS PER SECOND (MBPS) DOWNLINK AND 15MBPS UPLINK. But a key aspect highlighted by both OneWeb and Starlink is low latency, which reduces the time it takes for data to travel back and forth across the network. For a traditional geostationary communications satellite (GEO) located 36,000 kilometers above Earth, the ping time can be 700 milliseconds. For a new low-Earth orbit (LEO) satellite, that could be one-tenth of that, say, 80 milliseconds. "This allows you to do things like live (Microsoft) Teams calls. No lag, no lag, video runs smoothly, voice runs smoothly. ”。
At present, the only LEO systems that are really in operation or are clearly about to be put into operation are Musk's Starlink and Britain's OneWeb.
Original link: https://www.bbc.com/news/science-environment-65066669
- Trace amounts of plastic can cause terrible problems in chicken embryos
A recent study by researchers at Leiden University in the Netherlands found that nanoplastics — particles smaller than microplastics — cause absolutely terrible developmental problems in chicken embryos, leading to widespread malformations and birth defects in newborn chicks. "We see deformities in the nervous system, heart, eyes and other parts of the face."
The researchers manually injected a large number of tiny plastic particles into the embryo and then observed that when the nanoparticles adhered to the chick's neural crest cells, the plastic actually trapped these neural crest cells in the spine, preventing them from migrating with the blood to help form key parts of the body, including the heart and arteries, nervous system, facial features, and more.
Fortunately, the scientists did inject chicks with nanoparticles that were so far beyond extreme levels that the nanoparticles used for research "don't normally exist in living organisms." But this does not mean that the future is impossible. Scientists continue to discover microplastics in new and worrying places, from the depths of the ocean to the human placenta. As Science Alert points out, if plastic use hadn't slowed down, we should expect the world's environment to hold 900 million tonnes of microplastics by 2025, twice as much as in 2018.
Original link: https://futurism.com/neoscope/tiny-plastic-problems-chicken-embryos
- NASA's next group of astronauts on the moon will be more diverse than the last, including people of color and women
Fifty years have passed since the last astronaut landed on the moon. With the launch of Artemis 1 on November 16, 2022, NASA is finally ready to return personnel to the moon. This generation of astronauts will face new challenges. NASA wants them to stay on the moon longer and learn how to live there. Their work will pave the way for sending the first humans to Mars.
NASA's Apollo missions in the '60s and '70s put 24 white people on the moon. NASA has not yet selected the next group of lunar visitors. But there are only about 50 people to choose from. That includes 43 active astronauts and 10 candidates still in training. Members of this group come from diverse backgrounds. The list includes doctors and military pilots. It also includes geologists, microbiologists, engineers, and others. About a third (37%) of NASA's active astronauts are women.
NASA announced that the upcoming lunar mission will include the first woman and the first person of color.
Original link: https://www.snexplores.org/article/nasa-new-diverse-crew-astronauts-artemis-mission-moon
- A new study suggests that the Greenland ice sheet is nearing an irreversible melting point
The Greenland ice sheet covers 1.7 million square kilometers (660,200 square miles) of the Arctic. If it melts completely, global sea levels would rise by about 7 meters (23 feet), but scientists aren't sure how fast the ice sheet will melt, so modeling tipping points to derive key thresholds for irreversible changes in system behavior helps researchers figure out when melting is likely to occur.
A new modelling study based on a combination of carbon emissions essentially identifies two melting tipping points for the Greenland ice sheet: when 100 billion tonnes of carbon is released into the atmosphere, it will cause the southern part of the ice sheet to melt; Reaching 250 billion tonnes of carbon means permanent loss of almost the entire ice sheet. Previous studies have determined that 1 to 3 degrees Celsius (1.8 degrees Fahrenheit to 5.4 degrees Fahrenheit) of global warming is the threshold for irreversible melting of the Greenland ice sheet.
We have already emitted about 50 billion tons of carbon, about half way to the first tipping point. In fact, the Greenland ice sheet is already in the process of melting: between 2003 and 2016, it lost about 255 billion tons of ice per year. So far, most of the melting has occurred in the southern part of the ice sheet.
Original link: https://phys.org/news/2023-03-greenland-ice-sheet.html
- Studies have found that the Mediterranean diet reduces the risk of dementia
A new study suggests that eating a traditional Mediterranean-style diet — rich in foods like seafood, fruits and nuts — may help reduce the risk of dementia by nearly a quarter.
Experts at Newcastle University found that people who eat a Mediterranean-style diet have a 23% lower risk of dementia than those who don't.
The study, recently published in BMC Medicine, is one of the largest of its kind, as previous studies have typically been limited to small samples and a small number of dementia cases.
The scientists analyzed data from 60,298 people in the UK, including those from across the UK, and the researchers rated individuals based on how well their diets matched the main characteristics of the Mediterranean diet. Participants were followed for nearly a decade, during which time there were 882 cases of dementia.
At the same time, the genetic risk of developing dementia in each person is considered by estimating the so-called polygenic risk – a way to measure all the different genes associated with dementia risk.
Alzheimer's affects the lives of millions of people around the world, and options for treating the disease are currently limited. Therefore, finding ways to reduce our risk of dementia is a top priority for researchers and clinicians.
Research from Newcastle University suggests that eating a more Mediterranean diet may be a strategy to help individuals reduce their risk of Alzheimer's.
Original link: https://www.sciencedaily.com/releases/2023/03/230313215055.htm
- Why does weight loss fail by dieting? Probably because the brain amplifies the signals of hunger synapses
Many people who have dieted are familiar with the yo-yo effect: after a period of dieting, weight gain quickly returns.
Researchers have now shown in mice that communication in the brain changes during dieting: nerve cells that regulate hunger receive stronger signals, so mice eat more and gain weight faster after dieting. In the long term, the findings may help develop drugs to prevent the amplification of this signal and help maintain weight loss after dieting.
The researchers dieted mice and assessed which circuits in the brain had changed. In particular, they examined a group of neurons in the hypothalamus, known as AgRP neurons, known to control hunger. They were able to show that when mice were dieting, neuronal pathways that stimulated AgRP neurons sent more signals. This profound change in the brain can be detected long after dieting.
The researchers also succeeded in selectively inhibiting mouse neural pathways that activate AgRP neurons. This leads to a significant reduction in weight gain after dieting. This could give us the opportunity to reduce the yo-yo effect, and in the long run, the goal is to find therapies for humans that can help maintain weight loss after dieting. To achieve this goal, it is necessary to continue to explore how to block the mechanisms that regulate the strengthening of human neural pathways in the future.
Original link: https://www.sciencedaily.com/releases/2023/03/230324135218.htm