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https://paper.li/e-1437691924#/ https://www.nature.com/articles/s41591-019-0375-9


The hippocampus is one of the most affected areas in Alzheimer’s disease (AD). Moreover, this structure hosts one of the most unique phenomena of the adult mammalian brain, namely, the addition of new neurons throughout life. This process, called adult hippocampal neurogenesis (AHN), confers an unparalleled degree of plasticity to the entire hippocampal circuitry3,4. Nonetheless, direct evidence of AHN in humans has remained elusive. Thus, determining whether new neurons are continuously incorporated into the human dentate gyrus (DG) during physiological and pathological aging is a crucial question with outstanding therapeutic potential. By combining human brain samples obtained under tightly controlled conditions and state-of-the-art tissue processing methods, we identified thousands of immature neurons in the DG of neurologically healthy human subjects up to the ninth decade of life. These neurons exhibited variable degrees of maturation along differentiation stages of AHN. In sharp contrast, the number and maturation of these neurons progressively declined as AD advanced. These results demonstrate the persistence of AHN during both physiological and pathological aging in humans and provide evidence for impaired neurogenesis as a potentially relevant mechanism underlying memory deficits in AD that might be amenable to novel therapeutic strategies.

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The Post spoke to tech workers in Zhongguancun and other parts of Beijing for a snapshot of what life is really like living in China’s Silicon Valley, as these tech hubs – home to internet giants like Baidu, Meituan and ByteDance – have been dubbed.


Life in China’s tech industry is not easy, with young employees and entrepreneurs battling burnout while also worrying about career ceilings and lay-offs.

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In an electronic filing with the Federal Communications Commission (FCC), SpaceX has demonstrated a higher than necessary safety for their Starlink constellation satellites in terms of collision risk with other objects in orbit in the scenario that a Starlink satellite becomes uncontrollable after launch.

The filing, in response to FCC questions, reveals SpaceX’s upcoming space-based internet project carries a collision risk 2.1 times less likely than the accepted NASA standard.

The filing occurred on 13 March 2019 in response to a series of FCC follow-up questions from previous approvals and relates to SpaceX’s upcoming deployment of the first batch of Starlink satellites into an initial operational orbit of 550 km.

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Using a modified version of CRISPR, a team of geneticists has successfully triggered 13,200 genetic changes to a single human cell. That’s a new record, by a long shot. This sweeping new editing process could eventually be used to strip DNA of useless or dangerous genetic information—or create entirely new kinds of life.

New research uploaded to the preprint bioRxiv server describes the achievement, in which a Harvard University team led by George Church edited the living crap out of a single human cell to the tune of 13,200 total modifications. Incredibly, the cell survived. The previous record for bulk edits made to a single cell was set in 2017, when Church and his colleagues knocked out 62 copies of a retrovirus found in pig genomes. The new achievement is thus “three orders of magnitude greater” than the previous standard, the authors wrote in their paper.

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A new review discusses how neutrophils release toxic substances into the body under inflammatory conditions, detailing one of the ways in which chronic inflammation causes long-term damage.

Casting a deadly NET

As we age, we suffer from the ever-increasing chronic inflammation known as inflammaging. This persistent, smoldering background of low-grade inflammation harms wound healing and promotes multiple age-related diseases. Senescent cells, a weakened immune system, and chronic infections are all proposed to contribute to inflammaging.

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Over the past twenty years, neuroscientists have been quietly building a revolutionary technology called BrainGate that wirelessly connects the human mind to computers and it just hit the world stage. Entrepreneurs such as Elon Musk and Mark Zuckerberg have entered the race with goals of figuring out how to get computer chips into everyone’s brains. The attention of Musk and Zuckerberg means the potential for giant leaps forward. But the question no one seems to be asking is whether our dependence on machines and technology has finally gone too far. Countries annually celebrate their independence from other countries, but it now seems we should start asking deeper questions about our personal independence.

60 Minutes recently ran a piece showing how engineers are using what scientists have learned about the brain to manipulate us into staying perpetually addicted to our smartphones. The anxiety most of us feel when we are away from our phone is real: During the 60 Minutes piece, researchers at California State University Dominguez Hills connected electrodes to reporter Anderson Cooper’s fingers to measure changes in heart rate and perspiration. Then they sent text messages to his phone, which was out of his reach, and watched his anxiety spike with each notification.

The segment revealed that virtually every app on your phone is calibrated to keep you using it as often and as long as possible. The show made an important point: a relatively small number of Silicon Valley engineers are experimenting with, and changing in a significant way, human behavior and brain function. And they’re doing it with little insight into the long-term consequences. It seems the fight for independence has gone digital.

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