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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

lunedì 15 ottobre 2018

# soc-eu: Bavarian Greens could be the second party (18% by exit polls)

<< Now, multiple surveys show the Greens polling at 15-17 percent nationally, catching up with or even overtaking the SPD. >>

Zia Weise. The rise and rise of Bavaria’s Greens. Oct 12, 2018.

https://www.politico.eu/article/greens-bavaria-election-germany-the-rise-and-rise-of-bavarias-greens/

<< The Green wave: Glance casually at the election results in Bavaria, in Luxembourg, in Belgium’s communes, and you’ll find a Green wave engulfing the center-left of the political spectrum. Look a bit closer, and you’ll see the traditional political camps - the EPP and Social Democracy - fighting for survival. Mark this day in your calendars as a potential turning point for Europe. >>

Florian Eder. Brussels Playbook. Oct 15, 2018

https://www.politico.eu/newsletter/brussels-playbook/politico-brussels-playbook-presented-by-banco-santander-green-wave-bavarian-earthquake-brexit-crunch/

<< The polls said the Greens were making major gains to secure second place with up to 19 percent of the vote. >>

The Latest: Exit Polls: Top Party Losing Bavaria Majority.  The Associated Press. Oct 14, 2018

https://www.nytimes.com/aponline/2018/10/14/world/europe/ap-eu-germany-bavaria-election-the-latest.html

mercoledì 10 ottobre 2018

# evol: dry, chaotic environment in the transition to modern (nomadic) humans

<< A progressively drying climate punctuated by variable wetter episodes may have precipitated the transition from our hominin ancestors to anatomically modern humans >>

Dryer, less predictable environment may have spurred human evolution. University of Arizona. Oct 8, 2018.

https://m.phys.org/news/2018-10-dryer-environment-spurred-human-evolution.html

R. Bernhart Owen, Veronica M. Muiruri, et al. Progressive aridification in East Africa over the last half million years and implications for human evolution. PNAS Oct 8, 2018 doi: 10.1073/pnas.1801357115 

http://www.pnas.org/content/early/2018/10/03/1801357115