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2024-11-11

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Abstract

The ability to detect threats quickly is crucial for survival. Primates, including humans, have been shown to identify snakes quickly and accurately due to their evolutionary history. However, it is unclear which visual features humans and primates detect as threat targets. Several studies have suggested that snake scales possess potent visual features. My previous study demonstrated that removing snake scales through digital image processing reduces attention directed toward snakes. Here, I conducted a visual search task using luminance- and contrast-adjusted photographs of snakes and salamanders in monkeys that had never seen these real reptiles and amphibians. This study demonstrates that the presence or absence of snake scales is responsible for the rapid detection of target animals. The monkeys quickly detected one snake photograph from the eight salamander photographs than vice versa. However, when the same salamanders were clothed with snake scales using image processing, the difference in detection speed between snakes and salamanders disappeared. These results are consistent with the snake-detection theory that snakes were a strong selective pressure favoring modifications in the primate visual system that allow them to detect snakes more quickly or reliably. This strongly suggests that primates’ snake detection depends on the snake-scale shapes, which are both snake-specific and common to all snakes.

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Occupational stress is a trigger for Rebecca Wilde, a 32-year-old tech worker in Buckinghamshire. Four years ago, work pressures combined with family issues affected her sleep, leading to a severe manic episode. She was hospitalised for a month and a half, and diagnosed with type 1 bipolar disorder, also known as bipolar 1, a mood condition that can have devastating consequences if not managed well. Mania, and sometimes psychosis, is present in type 1.

Wilde was experiencing both: at one point, she thought she could talk to dogs. She was put on the antipsychotic drug olanzapine and another mood stabiliser, lithium. She has now been taking lithium alone for a year, and it has been transformative. “On the lithium, I definitely feel like me,” she says.

While Wilde was transitioning to lithium only, researchers were furiously debating the evidence around the drug. In 2023, the journal Bipolar Disorders published an editorial co-written by editor-in-chief Gin S Malhi, titled “Lithium first: not merely first line”. This asserted that lithium should be considered not only as one of several possible initial treatments for bipolar disorder, but as the first and foremost of these. Lithium “needs to be championed”, maintains Malhi, a visiting psychiatry professor at Oxford University.

This is not the only heated dispute among lithium researchers from the past couple of years. A 2024 critique led to professors trading words such as “pseudoscience” and “extraordinarily venomous”. Feuds such as these point to the high stakes over the declining popularity of lithium.

Medicinal lithium is remarkable. There is more evidence of lithium’s effectiveness in managing bipolar disorder than for any other medicine. As a naturally occurring ion, lithium can’t be patented. And unlike most medicines, it’s not metabolised by the body.

Malhi explains why this is significant: “With lithium, the body can be thought of simply as a bucket of water with input and output of fluid. Then, whatever lithium you add gives you a plasma level. It means we can accurately make changes with sensitivity around plasma levels and clinical response and tolerability.”

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Abstract

To compare the economic burden of disease and quality of life in patients with premature ejaculation (PE) and erectile dysfunction (ED). A convenience sampling method was used, and self-designed general information questionnaire, disease economic burden questionnaire, and SF-12 quality of life questionnaire were used to investigate 494 patients with ED and 285 patients with PE who attended a tertiary hospital in Taiyuan City from October 2021 to May 2023, and the relevant data were analysed using SPSS26.0 statistical software. The direct, indirect, intangible, and total economic burdens of the two groups were compared, and the differences were statistically significant (P < 0.05), and the direct, indirect, intangible, and total economic burdens of ED patients were higher than those of PE patients; the scores of the two groups in the dimensions of PF (physical function), RP (role physical), RE (role emotion), and MH (mental health) as well as in the MCS (mental component score), and overall quality of life scores, the differences were statistically significant (P < 0.05), with ED patients having lower quality of life scores than PE patients. Compared with PE patients, ED patients have a heavier economic burden of disease and lower quality of life, suggesting that the government and relevant departments of society should pay attention to the economic burden of disease and quality of life of ED patients and take appropriate measures to improve them.

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When a dog shakes water off its fur, the action is not just a random flurry of movements — nor a deliberate effort to drench anyone standing nearby.

This instinctive reflex is shared by many furry mammals including mice, cats, squirrels, lions, tigers and bears. The move helps animals to remove water, insects or other irritants from hard-to-reach places. But underlying the shakes is a complex — and previously mysterious — neurological mechanism.

Now, researchers have identified the neural circuit that triggers characteristic ‘wet dog’ shaking behaviour in mice — which involves a specific class of touch receptors, and neurons that connect the spinal cord to the brain. Their findings were published in Science on 7 November.

“The touch system is so complex and rich that [it] can distinguish a water droplet from a crawling insect from the gentle touch of a loved one,” says Kara Marshall, a neuroscientist at Baylor College of Medicine in Houston, Texas. “It’s really remarkable to be able to link a very specific subset of touch receptors to this familiar and understandable behaviour.”

Research article was featured on the cover of this issue of Science, with a glorious picture of a brown bear doing the "wet dog shake" (https://www.science.org/toc/science/current)

Research article: https://doi.org/10.1126/science.adq8834

Please let me know if there is paywall

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Math Is Still Catching Up to the Mysterious Genius of Srinivasa Ramanujan

https://www.quantamagazine.org/srinivasa-ramanujan-was-a-genius-math-is-still-catching-up-20241021/

Born poor in colonial India and dead at 32, Ramanujan had fantastical, out-of-nowhere visions that continue to shape the field today

@science

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In their analysis, the researchers found no significant differences in conspiracy mentality between the autistic group and the general population. Both groups scored similarly, indicating that being autistic does not inherently affect one’s general susceptibility to conspiracy beliefs.

This finding suggests that conspiracy mentality is not linked with autism, contradicting two potential hypotheses the researchers explored: one that autism might increase susceptibility to conspiracy beliefs due to common experiences of social exclusion, and another that autism might offer a type of protection against these beliefs due to cognitive characteristics associated with autism, such as analytical thinking.

Link to the study:

https://www.tandfonline.com/doi/full/10.1080/13546805.2024.2399505#abstract

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