Latest news with #Scientists
Washington Post
a day ago
- Science
- Washington Post
See images of solar eruptions on the sun in unprecedented detail
Scientists have released the closest images ever taken near the sun, captured by NASA's Parker Solar Probe flying 3.8 million miles above the solar surface. In unprecedented detail, the visuals reveal how superhot ionized particles from the sun travel through space, information that can help improve forecasts of solar storms headed toward Earth.
ABC News
2 days ago
- Science
- ABC News
Dr Ann's Secret Lives: S1 Episode 1 Bull Sharks
Dr Ann's Secret Lives ALL EPISODES Science Animals Informative Watch Article share options Share this on Facebook Twitter Send this by Email Copy link WhatsApp Messenger ABC's beloved nature nerd, Dr Ann gets hands on as she joins scientists researching some of the world's most elusive and sometimes dangerous animals, all in a bid to uncover their secrets.
Daily Mail
2 days ago
- Health
- Daily Mail
Suffer from headaches? Neanderthal DNA could be to blame, study suggests
From the sound of traffic to spending too much time on your smartphone, there are plenty of things in the modern world that can give you a headache. But scientists now say that some people's pounding heads could have a far more ancient origin. According to new research, Neanderthal genes could be the reason that some people are more prone to a type of headache-causing brain defect. These defects, known as Chiari malformations, occur when the lower part of the brain extends too far into the spinal cord and affect about one in 100 people. In the mildest cases, these can cause headaches and neck pain, but larger malformations can lead to more serious conditions. Scientists previously suggested that these defects might have arisen when Homo sapiens interbred with other human species in the distant past. Since these ancient hominins had differently shaped skulls, genes that would lead to healthy development in their species could cause malformations in modern humans. In their paper, published in the journal Evolution, Medicine, and Public Health, the researchers have now specifically identified Neanderthal genes as the origin of this condition. The researchers suggested that the mildest form of Chiari malformation, known as CM-I, could have its roots in interbreeding between Homo sapiens and other hominins. To understand how these might have been transferred from our ancestors' relatives, the researchers examined the skulls of various human species. In the paper, published in Evolution, Medicine, and Public Health, compared 3D models of 103 modern people with and without Chiari malformations with eight fossils from ancient hominins. These included the skulls of Homo erectus, Homo Heidelbergensis, and Homo neanderthalensis - known as Neanderthals. Modern humans with the CM-I malformation had a number of differences in brain shape, mainly in the regions where the brain connects to the spine. However, when the researchers examined the skulls of ancient hominins, the only species with a similar skull shape was the Neanderthals. In fact, the skulls of Homo erectus and Homo Heidelbergensis were actually closer to humans without the malformation. Lead researcher Dr Kimberly Plomp says: 'Homo erectus and Homo heidelbergensis are both hypothesised to be ancestors of humans and Neanderthals, so to find that they were closer in shape to healthy human crania makes the similarities identified between Neanderthals and humans with Chairi even more persuasive. 'It means that the shape traits really seem to be unique to Neanderthals and humans with Chiari, and are not just part of our shared lineage. Since the researchers didn't do a genetic analysis, it is hard to say that Chiari-associated headaches are 'caused' by Neanderthal genes. However, Dr Plomp says it shows that some human skulls have shapes likely caused by Neanderthal genes, and those shapes can lead to Chiari malformations. That doesn't mean that every Neanderthal would have been walking around with constant headaches. However, although their large brains might have mitigated the issue, interbreeding with Homo sapiens might have given some Neanderthals a similar problem. Dr Plomp says: 'So our study suggests that the malformation can happen because the shape of our brain doesn't fit properly when our skull has some Neanderthal shape to it. 'Potentially, if there was a Neanderthal with some modern human cranial shape traits, their brain would not fit properly either.' Scientists believe that Homo sapiens and Neanderthals had two major periods of overlap and interbreeding. The first occurred around 250,000 years ago in what is now the modern-day Levant and lasted nearly 200,000 years. Previously, scientists had thought that these moments of interbreeding were fleeting one-off events. But new evidence is beginning to show that Neanderthals and Homo sapiens interbred much more frequently than scientists had previously considered. Today, up to 45 per cent of the complete Neanderthal genome survives across the modern human population, but the distribution of Neanderthal genes is highly dependent on Geography. This should allow the researchers to test their theory, since rates of Chiari malformations should be lower in areas with less Neanderthal DNA. Some people in East Asia get up to four per cent of their genes from Neanderthals, while in Africa, where Neanderthals never became established, many people have no Neanderthal genes whatsoever. If the theory is correct, rates of Chiari malformations should be significantly higher in East Asia than they are in Africa. Ultimately, the researchers hope these findings could inform methods for treating Chiari malformations or even stop them from happening in the first place. The paper concludes: 'The methods would seem to have the potential to help us develop a deeper understanding of the aetiology and pathogenesis of Chiari malformations, which could in turn strengthen diagnosis and treatment of the condition.' WHAT IS CHIARI MALFORMATION? Chiari malformation occurs when the brain tissue extends into the spinal canal. This can happen if the skull is abnormally small or misshapen, which presses the brain downwards. The Brain & Spine Foundation in the UK and the National Institute of Neurological Disorders and Stroke in the US both estimate one in every 1,000 people are born with the condition. It may actually be more common due to not all sufferers developing symptoms. There are three types of chiari malformation: Type I - occurs as the skull and brain are growing. Symptoms usually appear in late childhood or early adulthood and include neck pain, poor balance, co-ordination difficulties, numbness, dizziness and impaired vision Type II - is present at birth and related to spina bifida. Occurs when more of the brain tissue extends into the spinal cord than in Type I. Symptoms may include changes in breathing patterns, swallowing problems, arm weakness and quick downward eye movements Type III - is present at birth and the rarest form of chiari malformation. Occurs when a portion of the lower part of the brain extends through an abnormal opening in the back of the skull. Has a high mortality rate and can cause brain damage Although not usually considered life-threatening, chiari malformation may be fatal if a patient's breathing or swallowing is affected. It can also lead to hydrocephalus - the build-up of cerebral spinal fluid in the brain - which can be deadly if untreated. Treatment may not be necessary if symptoms are mild with just regular check-ups and MRI scans being required. However, surgery can be carried out to remove a small section of bone at the back of the skull. This relieves pressure by giving the brain more room. The procedure runs the risk of infections, fluid in the brain and spinal cord leaking. Although the operation helps to relieve symptoms it cannot cure nerve damage that has already occurred.
Yahoo
3 days ago
- Health
- Yahoo
Becoming active in adulthood can curb risk of dying from certain health issues by 22%, study finds
It's never too late to start exercising, according to a new study that found people who transition from inactive to active lifestyles in adulthood can reduce their mortality risks by 22 per cent. Health experts, scientists, and medical organisations agree that physical activity benefits both the body and the mind. What has been less clear is exactly how much exercise helps, which patterns of activity are most effective, and at which stages of life they are most important. The new study published in the British Journal of Sports Medicine (BJSM) aimed to answer those questions by identifying how physical activity during adulthood can influence the risk of dying from heart disease, cancer, and other health issues. Researchers analysed data from 85 studies of varying size. The number of participants per study ranged from 357 to over 6.5 million participants. Overall, the analysis found that exercising in adulthood can yield significant health benefits, reducing the risk of mortality by 20 per cent to 40 per cent. Specifically, adults who are regularly active can curb these risks by up to 30 per cent to 40 per cent. And even those who transition from an inactive to an active lifestyle can reduce their risk of death from any cause by approximately 22 per cent. Exercise does not appear to reduce all health risks equally. For example, it was tied to a 30 per cent to 40 per cent lower risk of death from heart disease, but the links to cancer mortality were less clear. Interestingly, not all types of exercise had the same effect on adults' health. The paper suggests that adults who work out in their spare time can reduce their health risks more than people who are active by happenstance at work or home. Some experts argue that the relationship between fitness and mortality risk is a little more nuanced than the latest study suggests. 'Based on these types of studies, we cannot very confidently say to what extent this lower mortality risk is due to the differences in activity or other factors that differ,' Marcel Ballin, who researches physical activity and health at Uppsala University in Sweden, told Euronews Next. That could include genetics and environmental exposures that influence people's health and well-being. For example, a study published in the European Journal of Epidemiology earlier this year found that genetics plays a significant role in mortality risk. While physical activity was relevant, longevity reflects people's overall health, not just that one factor, the study found. Ballin suggested the latest findings should be taken with a grain of salt. 'What we can say is that if you are belonging to a group that is more active than the average, and you're consistently being active or increasing your activity over time, it seems to be good for your mortality risk,' he said. 'But, we need to be more careful when attributing the lower mortality to the activity itself,' he added.
Daily Mail
5 days ago
- Science
- Daily Mail
What would happen if the Earth continues to spin faster? Stronger hurricanes, disastrous earthquakes and catastrophic flooding, expert says
Scientists have warned that this summer could include some of the shortest days of your entire life. On July 22 and August 5, experts predict the day will be 1.38 and 1.51 milliseconds shorter than average, respectively. This is because the planet's rotation has entered an unexpected period of acceleration, shaving a millisecond or so off the length of a solar day. But what would happen if the world just kept getting faster? Given that a blink takes 100 milliseconds, you are unlikely to notice any big changes for a long time. However, scientists say that unchecked acceleration would eventually lead to disastrous consequences. If Earth were spinning just 100 miles per hour faster than it does now, the world would be hit by stronger hurricanes, catastrophic flooding, and the collapse of satellite networks. And, if the world were to double its speed, it would likely be the end of life as we know it. One mile per hour faster On average, it takes the planet 24 hours, or 86,400 seconds, to complete one full rotation, which is called a solar day. Small fluctuations like the location of the moon or volcanic eruptions can shift this around a millisecond in either direction, but the rotation is generally fairly stable. Because the Earth is a sphere, its circumference is smaller near the poles than at the equator, so the planet's surface moves faster the further you get from the poles. Someone standing at the equator is rotating in space at around 1,037 mph (1,668 kmph) while somebody in London is only moving at about 646 mph (1,041 kmph). Compared to these speeds, an increase of just one mile per hour might not seem like a big difference. The days would be about a minute and a half shorter overall, which our body clocks probably wouldn't notice right away. Witold Fraczek, an analyst at ESRI, a mapping software firm, told Popular Science: 'It might take a few years to notice it.' However, an unexpected effect is that satellites in orbit would soon be knocked out of sync. Some satellites are 'geosynchronous', meaning they move at the same speed as Earth's rotation to stay over the same location. If the Earth speeds up, those satellites will lose their position and navigation, communication, and weather monitoring services would start to fail. However, some satellites carry fuel to adjust their orbit, and others could be replaced, so the results should not be disastrous. Mr Fraczek says: 'These could disturb the life and comfort of some people, but should not be catastrophic to anybody. The bigger impact is that water would start to move from the poles to the equator due to the increased centrifugal forces. Even at just one mile per hour, this would cause sea levels to rise by a few inches around the equator. For cities already at or very near sea level, this could lead to devastating flooding. 100 miles per hour faster If the Earth kept accelerating until it was moving 100 miles per hour faster at the equator, this would start to trigger seriously dangerous consequences. Rather than rising by a few inches, these speeds would start to drown the equator as water rushed down from the poles. Mr Fraczek says: 'I think the Amazon Basin, Northern Australia, and not to mention the islands in the equatorial region, they would all go under water. 'How deep underwater, I'm not sure, but I'd estimate about 30 to 65 feet.' For anyone who survived the flooding, the world would start to become a much more hostile place. The solar day would now only last 22 hours, knocking our circadian rhythms out of their natural balance. The effect would be like setting your body clock back two hours every day without being given a chance to adjust. Could the world keep getting faster? It is extremely unlikely that the world will start to spin faster. In fact, the world is actually slowing down over time. About 4.4 billion years ago, the planet was spinning so fast that days lasted four minutes. But this slowed down after a large object hit Earth and created the moon. The only way Earth could speed up is if a large object hits at just the right angle. But this would likely liquify the planet's crust, so no humans would survive to see the results. Studies have shown that changes like daylight saving lead to increased rates of heart attacks, strokes, and driving accidents - this would be even more severe. Additionally, Earth's weather would start to become more extreme. NASA astronomer Dr Sten Odenwald says: 'Temperature difference is still going to be the main driver of winds. However, at these speeds, Dr Odenwald says that 'hurricanes will spin faster, and there will be more energy in them.' This is due to something called the Coriolis effect, which gives hurricanes their rotational energy. If the Earth didn't spin, winds would blow down from the North Pole to the equator in a straight line. But as the Earth rotates, the wind becomes deflected eastward, and this is what gives a hurricane its spin. If the world starts to spin faster, the winds would be deflected more, and the Coriolis effect would become stronger. Dr Odenwald says: 'That effectively makes the rotation more severe.' 1,000 miles per hour faster or more At 1,000 miles per hour faster, Earth would be rotating roughly twice as fast as it does today, with disastrous consequences. Mr Fraczek says: 'It would clearly be a disaster.' The centrifugal forces would pull hundreds of feet of water towards the equator. 'Except for the highest mountains, such as Kilimanjaro or the highest summits of the Andes, I think everything in the equatorial region would be covered with water,' says Mr Fraczek. At 1,000 miles per hour faster, the centrifugal forces generated by spinning would also be much stronger. This would make it easier for water to escape the force of gravity and evaporate up into the atmosphere. The already flooded regions of the equator would experience near-constant rain and would be constantly shrouded in fog and mist. At really extreme speeds of around 17,000 miles per hour (27,350 kmph), 17 times faster than normal, the centrifugal forces would be powerful enough to overwhelm gravity. Anyone at the equator would become weightless as centrifugal force counteracted gravity, and you might even start to get 'reverse rain' as water falls up into the atmosphere. However, it is unlikely that there would be anyone around to see this since the equator would have long since become uninhabitable. Mr Franczek says: 'If those few miserable humans would still be alive after most of Earth's water had been transferred to the atmosphere and beyond, they would clearly want to run out of the equator area as soon as possible.' Finally, once the planet started to reach speeds of about 24,000 miles per hour (38,600 kmph) at the equator, life as we know it would pretty much be over. The centrifugal forces would now be so strong that they would start to flatten out the Earth like a spinning ball of clay. The tectonic plates would shift and the Earth's crust would crack, leading to catastrophic results. Mr Franczek says: 'We would have enormous earthquakes. The tectonic plates would move quickly and that would be disastrous to life on the globe.'
