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Full Version: Astronaut blood flowing backwards + Do head lice prefer some people more than others?
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Zero gravity made some astronauts’ blood flow backwards
https://www.newscientist.com/article/222...backwards/

EXCERPT: Being in zero gravity can have strange effects on the body – now it’s emerged that it can make people’s blood flow backwards. The changes to circulation caused two astronauts to develop small blood clots, which could have been fatal – but fortunately the man and woman affected came to no harm. The blood changes happened in a vessel called the left internal jugular vein [...] Zero gravity is known to change people’s blood flow, so Karina Marshall-Goebel of KBR in Houston and colleagues wondered if it would also affect this vein.

They carried out measurements and ultrasound scans of this blood vessel in nine men and two women both before and after their missions on the International Space Station, as well as 50 and 150 days into their flights. [...] Because of this surprise finding, the team asked a panel of experts to review all the previous scans and another small clot was spotted in one astronaut who had already returned to Earth. ... Marshall-Goebel says the findings may cause female astronauts to reconsider taking the contraceptive pill to suppress their periods while on the Space Station, as this raises the risk of blood clots... (MORE - details)



Do head lice prefer some people more than others?
https://sciencenorway.no/children-childr...rs/1567832

EXCERPT: . . . Bjørn Arne Rukke and his colleagues conducted two large surveys on lice among primary school pupils and lice in Norwegian households in 2008. They did a new study in 2018. The results of the latest survey have not been published, but the researchers are going through their data now. [...] The researchers used lice combs to comb through the hair of several thousand children at twelve schools in Oslo for their 2008 study. They recorded hair characteristics, among other factors.

Hair colour didn't matter, said Rukke, but people with wavy hair had the highest incidence of lice. People with straight hair had the least lice, and people with curly hair were in the middle. But what mattered much more was the length and thickness of the hair, Rukke said. People who had medium long hair had the highest incidence of lice compared to those who had short and long hair. People with short hair were least likely to have lice, and people with thick hair more often had lice than those with thin hair.

Some studies show that lice are more common in girls than boys. Rukke said the results from his own research are ambiguous. “Some of our results indicate that girls may have higher rates of lice than boys, while other results don’t. I can only speculate as to why. Maybe it is because they have longer hair, maybe they have closer contact, or maybe there’s something else,” he said. No one is immune, but frequent head checks help Anyone can get lice, and personal hygiene has nothing to do with the likelihood of being infested, Rukke said... (MORE - details)