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mercoledì 24 ottobre 2018

# brain: sometimes to see it is necessary to rewire

<< Life-changing moments are also brain-changing moments: everything from a first kiss to a last goodbye modifies cells within the skull. The capacity to learn and remember, however, extends beyond the profound experiences that we lament or treasure. In fact, a new study (..)  suggests that even when we're not consciously forming new memories, our brains can change in important ways, altering how we interpret and interact with the world. >>

Charles D. Gilbert. To see what's right in front of you, your brain may need some rewiring. Rockefeller University. Oct 24, 2018.

https://m.medicalxpress.com/news/2018-10-front-brain-rewiring.html

AA << found that during the course of perceptual learning axon collaterals in primary visual cortex (V1) undergo sprouting and pruning, suggesting how V1 is engaged in encoding learned information. >>

Timo van Kerkoerle, Sally A. Marik, et al. Axonal plasticity associated with perceptual learning in adult macaque primary visual cortex. PNAS Oct 9, 2018 115 (41) 10464-9 doi: 10.1073/pnas.1812932115

http://www.pnas.org/content/115/41/10464

lunedì 22 ottobre 2018

# brain: somatic stem cell proliferation could be modulated by autonomic nervous system

this << study (..) demonstrates, for the first time, that stem cell proliferation is directly controlled by the autonomic nervous system (ANS). >>

<< To demonstrate that stem cell behavior was changing as a result of ANS stimulation, the researchers grew intestinal epithelial cells in the lab and exposed them to high levels of two neurotransmitters, norepinephrine and acetylcholine. Norepinephrine is a major neurotransmitter of the sympathetic nervous system, or "fight or flight" branch of the ANS, while acetylcholine is produced by the parasympathetic nervous system, or "rest and digest" branch. >>

Scientists find stem cell proliferation is controlled directly by nervous system. University of Illinois at Urbana-Champaign. Oct 17, 2018.

https://m.phys.org/news/2018-10-scientists-stem-cell-proliferation-nervous.html

Elizabeth A. Davis, Megan J. Dailey. A direct effect of the autonomic nervous system on somatic stem cell proliferation?  Am J Physiol. doi: 10.1152/ajpregu.00266.2018. Oct 10, 2018.

https://www.physiology.org/doi/abs/10.1152/ajpregu.00266.2018

sabato 20 ottobre 2018

# gst: a new type of vortex in the flight of a dandelion

<< Wind-dispersed plants have evolved ingenious ways to lift their seeds >>

AA << visualized the flow around dandelion seeds, uncovering an extraordinary type of vortex. This vortex is a ring of recirculating fluid, which is detached owing to the flow passing through the pappus. >>

<< The discovery of the separated vortex ring provides evidence of the existence of a new class of fluid behaviour around fluid-immersed bodies that may underlie locomotion, weight reduction and particle retention in biological and manmade structures. >>

Cathal Cummins, Madeleine Seale, et al. A separated vortex ring underlies the flight of the dandelion. Nature 2018; 562: 414–8. doi: 10.1038/s41586-018-0604-2.

https://www.nature.com/articles/s41586-018-0604-2

<< When dandelion seeds fly, a ring-shaped air bubble forms as air moves through the bristles, enhancing the drag that slows their descent. >>

Dandelion seeds reveal newly discovered form of natural flight. University of Edinburgh. Oct 17, 2018.

https://m.phys.org/news/2018-10-dandelion-seeds-reveal-newly-natural.html

venerdì 19 ottobre 2018

# chem: to explore the structure of small molecules

<< In the many scientific endeavors that  are driven by organic chemistry, unambiguous identification of small molecules is of paramount importance (..) the  unambiguous determination of a small molecule’s structure  requires  X-ray  and/or neutron  diffraction  studies.  In practice, however,  X-ray crystallography is rarely applied in routine organic chemistry due to  intrinsic limitations  of both  the analytes and the technique. >>

AA << report the use of the CryoEM (cryo-electron microscopy) method MicroED (micro-electron diffraction) to provide routine and unambiguous structural determination of small organic molecules. >>

Christopher G. Jones, Michael W. Martynowycz, et al. The CryoEM Method MicroED as a Powerful Tool for Small Molecule Structure Determination. ChemRxiv Oct 17, 2018 doi: 10.26434/chemrxiv.7215332.v1

https://chemrxiv.org/articles/The_CryoEM_Method_MicroED_as_a_Powerful_Tool_for_Small_Molecule_Structure_Determination/7215332

https://twitter.com/ChemRxiv/status/1052562398295539712

giovedì 18 ottobre 2018

# astro: wormhole, a theoretical view of its quasinormal modes

AA << demonstrated how to describe the shape of any symmetrical wormhole - a black hole that theoretically can be a kind of a portal between any two points in space and time - based on its wave spectrum >>

Physicist describes the shape of a wormhole.  RUDN University. Oct 17, 2018.

https://m.phys.org/news/2018-10-physicist-wormhole.html

R.A.Konoplya. How to tell the shape of a wormhole by its quasinormal modes. Physics Letters B. Volume 784 Sep 10, 2018 Pages 43-49  doi: 10.1016/j.physletb.2018.07.025

https://www.sciencedirect.com/science/article/pii/S037026931830563X

mercoledì 17 ottobre 2018

# gst: when a 'ricequake' repeat perpetually and propagate

<< puffed rice and milk can serve as a stand-in to simulate collapsing ice shelves and rockfill dams. >>

<< Intrigued by their findings, the researchers created what they call a "crushing wave model," which they believe could prove useful for describing the behavior of much larger collapse events. >>

Bob Yirka. Using puffed rice to simulate collapsing ice shelves and rockfill dams. Oct 15, 2018.

https://m.phys.org/news/2018-10-puffed-rice-simulate-collapsing-ice.html

<< These "ricequakes" repeat perpetually during the experiments and propagate upward through the material. >>

Itai Einav, Francois Guillard. Tracking time with ricequakes in partially soaked brittle porous media. Science Advances  Oct 12, 2018. Vol. 4, no. 10, eaat6961. doi: 10.1126/sciadv.aat6961.

http://advances.sciencemag.org/content/4/10/eaat6961

martedì 16 ottobre 2018

# chem: it can self-repair by capturing carbon from the air

<< A material designed by MIT chemical engineers can react with carbon dioxide from the air, to grow, strengthen, and even repair itself. The polymer, which might someday be used as construction or repair material or for protective coatings, continuously converts the greenhouse gas into a carbon-based material that reinforces itself. >>

<< Materials science has never produced anything like this (..) These materials mimic some aspects of something living, even though it's not reproducing. >> Michael Strano

David L. Chandler. Self-healing material can build itself from carbon in the air. MIT. Oct 11, 2018.

https://m.phys.org/news/2018-10-self-healing-material-carbon-air.html 

Seon‐Yeong Kwak,  Juan Pablo Giraldo, et al. Polymethacrylamide and Carbon Composites that Grow, Strengthen, and Self‐Repair using Ambient Carbon Dioxide Fixation. Advanced Materials. Oct 9, 2018. doi: 10.1002/adma.201804037

https://onlinelibrary.wiley.com/doi/10.1002/adma.201804037