Daniel Lemire's blog

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Science and Technology links (March 10, 2017)

In Mnemonic Training Reshapes Brain Networks to Support Superior Memory (published in Neuron, March 2017), we learned that 6 weeks of mnemonic training at a rate of 30 minutes a day lead to a large scale brain network re-organization making the brain of control subjects more like that of memory athletes.

In How worried should we be about artificial intelligence?, Andrew Ng, the chief scientist of the search engine giant Baidu is quoted as saying: “Worrying about evil-killer AI today is like worrying about overpopulation on the planet Mars.” Another famous computer scientist, Moshe Vardi, was quoted as saying “the superintelligence risk, which gets more headlines, is not an immediate risk. We can afford to take our time to assess it in depth”. The article includes lots of interesting quotes by other scientists and thinkers.

In adult mammals, damaged nerve cells do not normally regenerate and neurogenesis is barely noticeable. So a damaged brain can route around the damage, but it does not normally repair itself fully. In an October 2016 article published in the journal Neuron, Tedeschi et al. showed that treating mice with the drug Pregabalin caused damaged nerve connections to regenerate. Speculatively, this could help find cures for neurodegenerative diseases.

Yann Collet, a Facebook engineer famous for LZ4, a fast compression format, has released Zstandard is a new compressed format that has superior performance. Though the software is open source, it may be covered by patents, so check with your lawyers.

Mice age faster than human beings: they barely live a couple of years whereas human beings can live decades. We don’t know how the cells know how fast they are supposed to develop and age. In vitro, the human and mice cells develop at different rates. What happens if you put human embryonic stem cells in mice? They still develop at a human rate. This suggests that the cells themselves are equipped with some kind of clock. What this clock might be is unknown. (Source: Barry et al., Species-specific developmental timing is maintained by pluripotent stem cells ex utero)

We know how to reset cells in live mice so that they become pluripotent stem cells (e.g., using the Yamanaka factors). That is, we rewind the clock of the cells to zero, in a live animal. See In Vivo Amelioration of Age-Associated Hallmarks by Partial Reprogramming by Ocampo et al. More recently, Marión et al. showed in Common Telomere Changes during In Vivo Reprogramming and Early Stages of Tumorigenesis that this is accompanied by what appears to be a reset on the length of the telomeres. The telomeres are a component of your chromosomes that get shorter with every division. Once the telomeres become too short, your cells stop dividing and may become senescent. Anyhow, it looks more and more certain that, yes, we can reset the age of cells in a living organism.