Translate

venerdì 17 aprile 2020

# life: how humans could mutate, step by step, into proto- alien entities ...

AA << studied the brain after long-duration space flight. The authors performed serial MRI on 11 of 54 eligible International Space Station astronauts (10 men, one woman; five astronauts had previous exposure to spaceflight; mean mission duration almost 6 months), both preflight and at 1 week, 1 month, 3 months, 6 months, and 1 year after spaceflight. They found that prolonged microgravity exposure caused the following brain changes: (a) an approximate 2% expansion of brain and cerebral spinal fluid (CSF) volumes, attributable to both white matter and lateral ventricular measurements, and these remained elevated at 1-year after spaceflight, suggesting permanent alterations; (b) a 13% increase in mean CSF intraventricular (aqueductal) flow velocity, suggesting a reduction in intracranial compliance; and (c) in roughly half (six of 11 astronauts), depression of the pituitary dome compared with baseline (average midline height decreased from 5.9 to 5.3 mm), suggesting elevated intracranial pressure during spaceflight. >>

Michael H. Lev. The Long-term Effects of Spaceflight on Human Brain Physiology. Radiology. doi: 10.1148/radiol.2020201164. Apr 14, 2020.

https://pubs.rsna.org/doi/10.1148/radiol.2020201164

Chelsea Gohd. Space travel can seriously change your brain. Apr 14, 2020.

https://www.space.com/brain-changes-in-space-astronaut-health-study.html


giovedì 16 aprile 2020

# gst: unusual properties of substances trapped in nanobubbles.

AA << modeled the behavior of nanobubbles appearing in van der Waals heterostructures and the behavior of substances trapped inside the bubbles. >>

<< The properties exhibited by substances inside the van der Waals nanobubbles are quite unusual. For example, water trapped inside a nanobubble displays a tenfold decrease in its dielectric constant and etches the diamond surface, something it would never do under normal conditions. Argon which typically exists in liquid form when in large quantities can become solid at the same pressure if trapped inside very small nanobubbles with a radius of less than 50 nanometers. >>

Substances trapped in nanobubbles exhibit unusual properties. Skolkovo Institute of Science and Technology. April 14, 2020.

https://phys.org/news/2020-04-substances-nanobubbles-unusual-properties.html

T. F. Aslyamov,  E. S. Iakovlev, et al. Model of graphene nanobubble: Combining classical density functional and elasticity theories. J. Chem. Phys. 152, 054705. Feb 3, 2020. 

https://aip.scitation.org/doi/10.1063/1.5138687

martedì 14 aprile 2020

# gene: stuttering, syncopated (but not junk) codes

<< All organisms have DNA, the genetic material that provides a blueprint for life. The long double-helix-shaped DNA molecules in the body's cells are first translated into RNA molecules and then translated into proteins that ensure the functioning of the cell and the entire organism. But there are large parts of the DNA that are not used for making proteins. This is called 'junk DNA', because its function remained unclear for a long time. However, a certain type of junk DNA that is found in mosquitoes and which repeats itself dozens of times, known as 'satellite DNA', has now been shown to play an essential role in the early development of mosquito embryos. >>

Stuttering DNA orchestrates the start of the mosquito's life. Radboud University Medical Center. Apr 9, 2020.

https://www.sciencedaily.com/releases/2020/04/200409100332.htm 

AA << results reveal a mechanism by which satellite repeats regulate global gene expression in trans via piRNA-mediated gene silencing that is essential for embryonic development. >>

Rebecca Halbach, Pascal Miesen, et al. A satellite repeat-derived piRNA controls embryonic development of Aedes. Nature 580, 274–277. doi: 10.1038/s41586-020-2159-2. 
Apr 1, 2020.

https://www.nature.com/articles/s41586-020-2159-2

Also

keyword 'piRNA' in ncbi pubmed

"piRNA"[all] AND (Review[ptyp]) AND ("last 3 years"[PDat])

http://www.ncbi.nlm.nih.gov/pubmed


sabato 11 aprile 2020

# gst: ab.normal (fuzzy, bizarre) Nature; apparently, ancient bacterial parasites could have used CRISPR to self-defense and 'interference' for Ma ...

<< In recent years, the development of CRISPR technologies and gene-editing scissors in particular have taken the world by storm. Indeed, scientists have learned how to harness these clever natural systems in the biotech and pharmaceutical industries, among other areas. >>

<< New research (..) shows that we are not the first to find a way to exploit the benefits of the CRISPR technique. Apparently, primitive bacterial parasites have been doing so for millions of years. >>

<< Until recently, CRISPR-Cas was believed to be a defense system used by bacteria to protect themselves against invading parasites such as viruses, much like our very own immune system protects us. However, it appears that CRISPR is a tool that can be used for different purposes by diverse biological entities, (..) Here we found evidence that certain plasmids use type IV CRISPR-Cas systems to fight other plasmids competing over the same bacterial host. >> Rafael Pinilla-Redondo.

Humans are not the first to repurpose CRISPR. University of Copenhagen. Mar 24, 2020.

https://phys.org/news/2020-03-humans-repurpose-crispr.html

Rafael Pinilla-Redondo, David Mayo-Muñoz, et al. Type IV CRISPR–Cas systems are highly diverse and involved in competition between plasmids.  Nucleic Acids Research, Vol. 48, Issue 4, Pages 2000–12. doi: 10.1093/nar/gkz1197. Dec 27, 2019.

https://academic.oup.com/nar/article/48/4/2000/5687823

Also

keyword 'CRISPR' (Clustered Regularly Interspaced Short Palindromic Repeat) in PubMed:

 "CRISPR"[all] AND (Review[ptyp]) AND ("last 3 years"[PDat])

https://www.ncbi.nlm.nih.gov/pubmed/

keyword 'CRISPR' in FonT:

https://flashontrack.blogspot.com/search?q=crispr

keyword 'interferenza' | 'interferente' in Notes (quasi-stochastic poetry):

https://inkpi.blogspot.com/search?q=interferenza

https://inkpi.blogspot.com/search?q=interferente

venerdì 10 aprile 2020

# brain: related noise in perception, like a type of "groupthink"

<< The findings, (..) offer new insights into the limits of perception and could aid in the design of so-called neuroprosthetics-devices that enable people to regain some lost sensory capabilities. >>

<< because neurons are highly interconnected, when one randomly responds incorrectly and misidentifies an image, it can influence other neurons to make the same mistake. >>

<< You can think of correlated noise like a type of 'groupthink,' in which neurons can act like lemmings, with one heedlessly following another into making a mistake, >> Surya Ganguli

<< Remarkably, the visual system is able to cut through about 90% of this neuronal noise, but the remaining 10% places a limit on how finely we can discern between two images that look very similar. >>

<< With this study, we've helped resolve a puzzle that's been around for over 30 years about what limits mammals-and by extension humans-when it comes to sensory perception, >> Mark Schnitzer

Adam Hadhazy. Misfiring from jittery neurons sets fundamental limit on perception.  Stanford University. Apr 9, 2020.

https://medicalxpress.com/news/2020-04-misfiring-jittery-neurons-fundamental-limit.html

Rumyantsev OI, Lecoq JA, et al. Fundamental bounds on the fidelity of sensory cortical coding. Nature 580, 100–105 doi:.10.1038/ s41586-020-2130-2. Mar 18, 2020.

https://www.nature.com/articles/s41586-020-2130-2


lunedì 6 aprile 2020

# gst: apropos of slipping, the motion on a deformable ground under fast-moving sheets

<< Backed by experimental data from a laboratory machine that simulates the huge forces involved in glacier flow, glaciologists have written an equation that accounts for the motion of ice that rests on the soft, deformable ground underneath unusually fast-moving parts of ice sheets. >>

<< That equation - or "slip law" - is a tool that scientists can include in computer models of glacier movement over the deformable beds of mud, sand, pebbles, rocks and boulders under glaciers such as the West Antarctic Ice Sheet, >> Neal Iverson

<< Models using the new slip law could better predict how quickly glaciers are sliding, how much ice they're sending to oceans and how that would affect sea-level rise. >>

Neal Iverson. Experiments lead to slip law for better forecasts of glacier speed, sea-level rise. Iowa State University. Apr 2, 2020.

https://m.phys.org/news/2020-04-law-glacier-sea-level.html

<< These observations should help to solve the long-standing problem of constructing a generalized slip law that combines the processes of hard-bedded sliding and bed deformation. >>

Lucas K. Zoet, Neal R. Iverson. A slip law for glaciers on deformable beds.  Science. Vol. 368, Issue 6486, pp. 76-78 doi: 10.1126/science.aaz1183.  Apr 3, 2020.

https://science.sciencemag.org/content/368/6486/76


sabato 4 aprile 2020

# life: 27 proteins to confine a world to a (complex 3D) virus dance

<< The novel coronavirus sweeping the globe packs 27 proteins, each adopting a unique, often incredibly complex 3D structure. 
Each protein is part of the molecular toolkit that the virus uses to infect, replicate, and spread. >>

Tom Rickey. Scientists Take Aim at the Coronavirus Toolkit. PNNL. Mar 31, 2020.

https://www.pnnl.gov/news-media/scientists-take-aim-coronavirus-toolkit

https://phys.org/news/2020-04-scientists-aim-coronavirus-toolkit.html

Also 

keyword 'dance' in FonT 

https://flashontrack.blogspot.com/search?q=dance

Also (quasi-stochastic poetry)

Catalisi d'astrattivo Tao. FonT.  Jan 22, 2005.

https://inkpi.blogspot.com/2005/01/1808-catalisi-dastrattivo-tao.html