In a world-first study published last weekend in the journal Cognition, a team of international researchers has reported some surprising findings relating to facial recognition.

The first discovery is that one’s ability to recognise faces has nothing to do with how extraverted, sociable, or gregarious a person is. What is clear, however, is that good facial recall is linked to the number of close, high-quality relationships that people have.

Researchers from the University of South Australia (UniSA), University of Western Australia (UWA) and Curtin University, along with US colleagues from Wellesley College and Harvard Medical School, undertook four separate studies involving more than 3000 people to tease out the relationship between facial recognition, social networks and personality traits.

In tests where participants memorised new faces or identified celebrity faces, their scores correlated with the number of close relationships they enjoyed.

“People who identified more faces typically had larger supportive social networks, which bodes well for their overall health and happiness,” says lead researcher UniSA psychologist Dr Laura Engfors.

“In concrete terms, the rise from the lowest (two) to the highest (28) number of faces that were successfully recognised on one test coincided with six additional close relationships, increasing from nine to 15. That’s an increase of two thirds and it is one extra strong social bond per four famous people recognised.”

The research did not find any link between facial recognition and a more social personality.

“Our findings rule out the idea that being sociable means you’ll probably be great at recognising faces. It also helps to dispel the common misconception that not recognising someone means you are less sociable.

“The ability to recognise faces more easily also means people may develop relationships faster.

“Imagine you’ve had an engaging conversation with someone you have only just met. A few weeks later you run into them again. If you recognise them quickly and easily, it opens the door to develop the rapport you established in your first meeting, helping the relationship to progress.

“On the flip side, if you don’t recognise them, you’ve missed the chance to build on that initial interaction,” Dr Engfors says.

Curtin University researcher and co-author Dr Linda Jeffery says being recognised by someone is a boost to a person’s self-esteem.

“It can make us feel important and valued, leading us to relate to that person more warmly, whereas we feel snubbed if someone we have met before does not recognise us.”

Wellesley College psychologist and co-author Associate Professor Jeremy Wilmer hopes the findings will be used to build stronger communities that facilitate human connection.

“Understanding that not everyone finds it easy to recognise people can help us to support those around us in social interactions,” Prof Wilmer says.

“Something as simple as name tags at a community barbecue or school event can make the difference between a connection built and a connection lost. Similarly, if you catch a flicker of uncertainty on someone’s face when you say hello, a subtle reminder to help them place you will be appreciated.”

People can test their own celebrity face recognition at the researchers’ citizen science website TestMyBrain.org.

New research, published today in Environment International proves for the first time that a wide range of PFAS (perfluoroalkyl substances) — chemicals which do not break down in nature — can permeate the skin barrier and reach the body’s bloodstream.

PFAS are used widely in industries and consumer products from school uniforms to personal care products because of their water and stain repellent properties. While some substances have been banned by government regulation, others are still widely used and their toxic effects have not yet been fully investigated.

PFAS are already known to enter the body through other routes, for example being breathed in or ingested via food or drinking water, and they are known to cause adverse health effects such as a lowered immune response to vaccination, impaired liver function and decreased birth weight.

It has commonly been thought that PFAS are unable to breach the skin barrier, although recent studies have shown links between the use of personal care products and PFAS concentrations in human blood and breast milk. The new study is the most comprehensive assessment yet undertaken of the absorption of PFAS into human skin and confirms that most of them can enter the body via this route.

Lead author of the study, Dr Oddný Ragnarsdóttir carried out the research while studying for her PhD at the University of Birmingham. She explained: “The ability of these chemicals to be absorbed through skin has previously been dismissed because the molecules are ionised. The electrical charge that gives them the ability to repel water and stains was thought to also make them incapable of crossing the skin membrane.

“Our research shows that this theory does not always hold true and that, in fact, uptake through the skin could be a significant source of exposure to these harmful chemicals.”

The researchers investigated 17 different PFAS. The compounds selected were among those most widely used, and most widely studied for their toxic effects and other ways through which humans might be exposed to them. Most significantly, they correspond to chemicals regulated by the EU’s Drinking Water Directive.

In their experiments the team used 3D human skin equivalent models — multilayered laboratory grown tissues that mimic the properties of normal human skin, meaning the study could be carried out without using any animals. They applied samples of each chemical to measure what proportions were absorbed, unabsorbed, or retained within the models.

Of the 17 PFAS tested, the team found 15 substances showed substantial dermal absorption — at least 5% of the exposure dose. At the exposure doses examined, absorption into the bloodstream of the most regulated PFAS (perfluoro octanoic acid (PFOA)) was 13.5% with a further 38% of the applied dose retained within the skin for potential longer-term uptake into the circulation.

The amount absorbed seemed to correlate with the length of the carbon chain within the molecule. Substances with longer carbon chains showed lower levels of absorption, while compounds with shorter chains that were introduced to replace longer carbon chain PFAS like PFOA, were more easily absorbed. Absorption of perfluoro pentanoic acid for example was four times that of PFOA at 59%.

Study co-author, Dr Mohamed Abdallah, said “our study provides first insight into significance of the dermal route as pathway of exposure to a wide range of forever chemicals. Given the large number of existing PFAS, it is important that future studies aim to assess the risk of broad ranges of these toxic chemicals, rather than focusing on one chemical at a time.”

Study co-author, Professor Stuart Harrad, of the University of Birmingham’s School of Geography, Earth and Environmental Sciences, added: “This study helps us to understand how important exposure to these chemicals via the skin might be and also which chemical structures might be most easily absorbed. This is important because we see a shift in industry towards chemicals with shorter chain lengths because these are believed to be less toxic — however the trade-off might be that we absorb more of them, so we need to know more about the risks involved.”

Among the first X-ray binary systems discovered in the cosmos is the system Cygnus X-3. Since the early 1970s, this binary system was noted for its ability to briefly emerge as one of the most intense radio sources, yet in a few days it dims or vanishes altogether. This peculiar characteristic spurred early efforts, coordinated by telephone calls, to unite astronomical observations across the globe. The unique behavior of the system during these short-lived, highly energetic events, contrasting its otherwise “normal” nature, led to it being dubbed the “astronomical puzzle Cygnus X-3” by R.M. Hjellming in 1973. Numerous efforts have been aimed at understanding its nature ever since.

The breakthrough in unravelling this puzzle has been achieved thanks to the study of this system with the satellite Imaging X-ray Polarimetry Explorer (IXPE) that was launched by NASA in December 2021. According to Alexandra Veledina, an Academy Research Fellow at the University of Turku in Finland and the lead author of the study, the use of X-ray polarized vision has provided insights into the configuration of matter surrounding the compact object in the nearest proximity to the black hole.

“We have discovered that the compact object is surrounded by an envelope of a dense, opaque matter. The light that we observe is a reflection off the inner funnel walls formed by the surrounding gas, resembling a cup with a mirror interior,” Veledina explains.

This revelation has led to the identification of Cygnus X-3 as a member of the class of ultra-luminous X-ray sources (ULXs), which consume matter at such a gargantuan rate that a considerable fraction of the infalling material does not fit inside the event horizon, but rather is being spat away from the system.

“ULXs are typically observed as luminous spots in the images of distant galaxies, with their emissions amplified by the focusing effects of the compact object’s surrounding funnel, acting akin to a megaphone,” elaborates Juri Poutanen, Professor at the Department of Physics and Astronomy of the University of Turku and a co-author of the research.

“However, due to the vast distances to these sources, thousands of times beyond the span of the Milky Way, they appear relatively faint to X-ray telescopes. Our discovery has now unveiled a bright counterpart of these distant ULXs residing within our own Galaxy.”

This significant finding marks a new chapter in the investigation of this extraordinary cosmic source, offering an opportunity for in-depth exploration of extreme matter consumption.