This study, published in The Astrophysical Journal, was performed by a multi-year cohort of undergraduate researchers in the Penn State branch of the Pulsar Search Collaboratory student club. Maura McLaughlin, Chair, Eberly Distinguished Professor of Physics and Astronomy, West Virginia University, created the Pulsar Search Collaboratory to engage high schoolers and undergraduates in pulsar science, and she helped facilitate access to the data used in this study. Using archival data from the Arecibo Observatory, the student team found patterns that show how pulsar signals change as they move through the interstellar medium (ISM), the gas and dust that fills the space between stars. The team measured scintillation bandwidths for 23 pulsars, including new data for six pulsars not previously studied. The results showed that in almost all cases, measured bandwidths were higher than predictions by widely used models of the galaxy, highlighting a need for updates to current ISM density models.

“This work demonstrates the value of large, archived datasets,” said Dr. Sofia Sheikh, SETI Institute researcher and lead author. “Even years after the Arecibo Observatory’s collapse, its data continues to unlock critical information that can advance our understanding of the galaxy and enhance our ability to study phenomena like gravitational waves.”

When radio light from a pulsar travels through the ISM, it gets distorted in a process known as “diffractive interstellar scintillation” (DISS). The same physics that makes light refract into patterns on the bottom of a swimming pool or causes stars to twinkle in the night sky also causes DISS. Instead of water in a pool or air in the atmosphere, DISS occurs when clouds of charged particles in space cause a pulsar’s light to “twinkle” across time and frequency.

Collaborations such as the NANOGrav Physics Frontiers Center use pulsars to study the gravitational wave background, which can help researchers understand the early Universe and the prevalence of gravitational-wave sources such as supermassive black-hole binaries. The pulsar timing measurements must be extremely precise to measure the gravitational wave background correctly. The results from this study will help better model the distortions caused by DISS, which will increase the precision of the pulsar timing measurements of projects like NANOGrav.

The study found that models incorporating galactic structures, such as spiral arms, tend to better fit the DISS data despite the challenge of accurately modeling the Milky Way’s structure. Moreover, the study showed that the models most accurately predicted the bandwidths of pulsars that were used in their development while predictions of newly discovered pulsars were worse. This suggests limitations that reinforce the need for continual updates to galactic structure models.”

This pilot study, part of the AO327 survey from Arecibo, serves as a foundation for future research on pulsar scintillation and gravitational waves. By expanding the pilot study to more recently discovered pulsars in the AO327 dataset in the future, the team hopes to further improve ISM density models for collaborations that observe pulsar timing arrays like NANOGrav.

This research involves the collaboration between authors at the SETI Institute, Penn State, and the NANOGrav Group at West Virginia University. The team includes SETI Institute researcher Michael Lam and former SETI Institute researcher Grayce Brown.

There is evidence that alcohol consumption is influenced by prenatal sex steroids so experts from Swansea University and colleagues from the Medical University of Lodz decided to use a sample of students for their research into the subject.

Their findings have just been published by the online journal American Journal of Human Biology. They found relationships between high alcohol consumption and long 4^th digits relative to 2^nd digits. This showed that high prenatal testosterone relative to oestrogen is linked to high student alcohol consumption.

Professor John Manning, of Swansea’s Applied Sports, Technology, Exercise and Medicine (A-STEM) research team, said: “Alcohol consumption is a major social and economic problem. Therefore, it is important to understand why alcohol use shows considerable differences across individuals.”

The study used a sample of 258 participants — 169 of them female — and it revealed consumption rates varied between the sexes. In comparison to women, men show higher alcohol consumption and higher mortality from alcohol abuse.

He said: “A pattern like this suggests an involvement of sex hormones, such as testosterone and oestrogen. Digit ratio (2D:4D: the relative lengths of the 2^nd [index] and 4^th [ring] fingers) is thought to be an index of early testosterone (long 4^th digit) and oestrogen (long 2^nd digit).

“It is known that alcohol-dependent patients have very long 4^th digits relative to their 2^nd digits, suggesting high testosterone relative to estrogen exposure before birth. As expected, the associations were stronger for men than women.”

Now the researchers hope their conclusions will bring a better understanding of the factors underlying the pattern of alcohol consumption, from abstinence to occasional use to harmful dependence.

This is the latest paper which has highlighted Professor Manning’s work in the field of digit ratios. Previous research has examined how digit ratio may provide vital information concerning outcomes after contracting Covid-19, as well as oxygen consumption in footballers.

All this may not be breaking news to everyone, but amid this upward march in average temperatures, a striking new phenomenon is emerging: distinct regions are seeing repeated heat waves that are so extreme, they fall far beyond what any model of global warming can predict or explain. A new study provides the first worldwide map of such regions, which show up on every continent except Antarctica like giant, angry skin blotches. In recent years these heat waves have killed tens of thousands of people, withered crops and forests, and sparked devastating wildfires.

“The large and unexpected margins by which recent regional-scale extremes have broken earlier records have raised questions about the degree to which climate models can provide adequate estimates of relations between global mean temperature changes and regional climate risks,” says the study.

“This is about extreme trends that are the outcome of physical interactions we might not completely understand,” said lead author Kai Kornhuber, an adjunct scientist at the Columbia Climate School’s Lamont-Doherty Earth Observatory. “These regions become temporary hothouses.” Kornhuber is also a senior research scholar at the International Institute for Applied Systems Analysis in Austria.

The study was just published in the journal Proceedings of the National Academy of Sciences.

The study looks at heat waves over the past 65 years, identifying areas where extreme heat is accelerating considerably faster than more moderate temperatures. This often results in maximum temperatures that have been repeatedly broken by outsize, sometimes astonishing, amounts. For instance, a nine-day wave that hammered the U.S. Pacific Northwest and southwestern Canada in June 2021 broke daily records in some locales by 30 degrees C, or 54 F. This included the highest ever temperature recorded in Canada, 121.3 F, in Lytton, British Columbia. The town burned to the ground the next day in a wildfire driven in large part by the drying of vegetation in the extraordinary heat. In Oregon and Washington state, hundreds of people died from heat stroke and other health conditions.

These extreme heat waves have been hitting predominantly in the last five years or so, though some occurred in the early 2000s or before. The most hard-hit regions include populous central China, Japan, Korea, the Arabian peninsula, eastern Australia and scattered parts of Africa. Others include Canada’s Northwest Territories and its High Arctic islands, northern Greenland, the southern end of South America and scattered patches of Siberia. Areas of Texas and New Mexico appear on the map, though they are not at the most extreme end.

According to the report, the most intense and consistent signal comes from northwestern Europe, where sequences of heat waves contributed to some 60,000 deaths in 2022 and 47,000 deaths in 2023. These occurred across Germany, France, the United Kingdom, the Netherlands and other countries. Here, in recent years, the hottest days of the year are warming twice as fast the summer mean temperatures. The region is especially vulnerable in part because, unlike places like the United States, few people have air conditioning, because traditionally it was almost never needed. The outbreaks have continued; as recently as this September, new maximum temperature records were set in Austria, France, Hungary, Slovenia, Norway and Sweden.

The researchers call the statistical trends “tail-widening” that is, the anomalous occurrence of temperatures at the far upper end, or beyond, anything that would be expected with simple upward shifts in mean summer temperatures. But the phenomenon is not happening everywhere; the study shows that maximum temperatures across many other regions are actually lower than what models would predict. These include wide areas of the north-central United States and south-central Canada, interior parts of South America, much of Siberia, northern Africa and northern Australia. Heat is increasing in these regions as well, but the extremes are increasing at similar or lower speed than what changes in average would suggest.

Climbing overall temperatures make heat waves more likely in many cases, but the causes of the extreme heat outbreaks are not entirely clear. In Europe and Russia, an earlier study led by Kornhuber blamed heat waves and droughts on wobbles in the jet stream, a fast-moving river of air that continuously circles the northern hemisphere. Hemmed in by historically frigid temperatures in the far north and much warmer ones further south, the jet stream generally confines itself to a narrow band. But the Arctic is warming on average far more quickly than most other parts of the Earth, and this appears to be destabilizing the jet stream, causing it to develop so-called Rossby waves, which suck hot air from the south and park it in temperate regions that normally do not see extreme heat for days or weeks at a time.

This is only one hypothesis, and it does not seem to explain all the extremes. A study of the fatal 2021 Pacific Northwest/southwestern Canada heat wave led by Lamont-Doherty graduate student Samuel Bartusek (also a coauthor on the latest paper) identified a confluence of factors. Some seemed connected to long-term climate change, others to chance. The study identified a disruption in the jet stream similar to the Rossby waves thought to affect Europe and Russia. It also found that decades of slowly rising temperatures had been drying out regional vegetation, so that when a spell of hot weather came along, plants had fewer reserves of water to evaporate into the air, a process that helps moderate heat. A third factor: a series of smaller-scale atmospheric waves that gathered heat from the Pacific Ocean surface and transported it eastward onto land. Like Europe, few people in this region have air conditioning, because it is generally not needed, and this probably upped the death toll.

The heat wave “was so extreme, it’s tempting to apply the label of a ‘black swan’ event, one that can’t be predicted,” said Bartusek. “But there’s a boundary between the totally unpredictable, the plausible and the totally expected that’s hard to categorize. I would call this more of a grey swan.”

While the wealthy United States is better prepared than many other places, excessive heat nevertheless kills more people than all other weather-related causes combined, including hurricanes, tornadoes and floods. According to a study out this past August, the yearly death rate has more than doubled since 1999, with 2,325 heat-related deaths in 2023. This has recently led to calls for heat waves to be named, similar to hurricanes, in order to heighten public awareness and motivate governments to prepare.

“Due to their unprecedented nature, these heat waves are usually linked to very severe health impacts, and can be disastrous for agriculture,vegetation and infrastructure,” said Kornhuber. “We’re not built for them, and we might not be able to adapt fast enough.”

The study was also coauthored by Richard Seager and Mingfang Ting of Lamont-Doherty Earth Observatory, and H.J. Schellnhuber of the International Institute for Applied Systems Analysis.