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Visualizzazione dei post in ordine di pertinenza per la query dance. Ordina per data Mostra tutti i post
Visualizzazione dei post in ordine di pertinenza per la query dance. Ordina per data Mostra tutti i post

mercoledì 21 febbraio 2024

# gst: when volatile droplets dance across a surface erratically (along random trajectories)

<< When a drop of a volatile liquid is deposited on a uniformly heated wettable, thermally conducting substrate, one expects to see it spread into a thin film and evaporate. >>️

<< Contrary to this intuition, due to thermal Marangoni contraction, the deposited drop contracts into a spherical-cap-shaped puddle, with a finite apparent contact angle. Strikingly, this contracted droplet, above a threshold temperature, well below the boiling point of the liquid, starts to spontaneously move on the substrate in an apparently erratic way. >>️

Pallav Kant, Mathieu Souzy, et al. Autothermotaxis of volatile drops. Phys. Rev. Fluids 9, L012001. Jan 31, 2024. 

Rachel Berkowitz. Hot Surfaces Make Droplets Move Erratically. Physics 17, s14. Jan 31, 2024. 

Also: drop, bubble, erratic

Keywords: gst, drop, bubble, erratic, thermotaxis, autothermotaxis


mercoledì 10 agosto 2022

# gst: a rocking shadow dance: the broken disk.

AA << reveal a new phenomenon dubbed the "rocking shadow" effect that describes how disks in forming planetary systems are oriented, and how they move around their host star. The effect also gives clues as to how they might evolve with time. >>

<< Protoplanetary disks are often thought to be shaped like dinner plates—thin, round and flat. However, recent telescope images from the Atacama Large Millimeter/Submillimeter Array (ALMA) show that this is not always the case. Some of the disks seen by ALMA have shadows on them, where the part of the disk closest to the star blocks some of the stellar light and casts a shadow onto the outer part of the disk. From this shadow pattern, it can be inferred that the inner part of the disk is oriented completely differently to the outer part, in what is called a broken disk. >>️️

<< As the inner disk moved through the gravitational pull of the central star, the shadow it cast moved across the outer disk. But instead of the shadow pattern moving around the disk like a clock-hand as expected, it rocked back and forth with a see-saw-like motion. So although the inside disk kept turning in the same direction, its shadow looked like it was rocking forwards and backwards. >>
Examining rocking shadows in protoplanetary disks. Royal Astronomical Society. Jul 15, 2022.


Rocking shadows in broken 
circumbinary discs. 


The National Astronomy Meeting (NAM) 2022. The University of Warwick, 11th. Jul 15, 2022.



keywords: gst, astro, shadow, rocking shadow, broken disc






giovedì 29 luglio 2021

# life: apropos of fuzzy cooperation, Ralph fuzzy mixture vs. world fuzzy dance ...

<< In 2013, the American virologist Ralph Baric approached Zhengli Shi at a meeting. Baric was a top expert in coronaviruses, with hundreds of papers to his credit, and Shi, along with her team at the Wuhan Institute of Virology, had been discovering them by the fistful in bat caves. In one sample of bat guano, Shi had detected the genome of a new virus, called SHC014, that was one of the two closest relatives to the original SARS virus, but her team had not been able to culture it in the lab. >>️

<< Baric had developed a way around that problem—a technique for “reverse genetics” in coronaviruses. Not only did it allow him to bring an actual virus to life from its genetic code, but he could mix and match parts of multiple viruses. He wanted to take the “spike” gene from SHC014 and move it into a genetic copy of the SARS virus he already had in his lab. The spike molecule is what lets a coronavirus open a cell and get inside it. The resulting chimera would demonstrate whether the spike of SHC014 would attach to human cells. >>️

<< Just as when you trade in part of a poker hand for fresh cards, there was no way of knowing whether the final chimeras would be stronger or weaker. >>

<< If you study a hundred different bat viruses, your luck may run out. >> Ralph Baric. 

<< In 2014, the NIH awarded a five-year, $3.75 million grant to EcoHealth Alliance to study the risk that more bat-borne coronaviruses would emerge in China, using the same kind of techniques Baric had pioneered. Some of that work was to be subcontracted to the Wuhan Institute of Virology. >>

<< Consider this hypothetical scenario, (..) An important gain-of-function experiment involving a virus with serious pandemic potential is performed in a well-regulated, world-class laboratory by experienced investigators, but the information from the experiment is then used by another scientist who does not have the same training and facilities and is not subject to the same regulations. In an unlikely but conceivable turn of events, what if that scientist becomes infected with the virus, which leads to an outbreak and ultimately triggers a pandemic >>  Anthony Fauci (director of the NIH’s National Institute of Allergy and Infectious Diseases) (2012).
<< Paul’s grilling of Fauci brought new scrutiny to the relationship between Ralph Baric’s lab at UNC and Zhengli Shi’s at WIV, with some narratives painting Baric as the Sith master of SARS and Shi as his ascendant apprentice. They did share resources—for example, Baric sent the transgenic mice with human lung receptors to Wuhan.  >>
<< During a hearing on May 11, 2021, Senator Rand Paul confronted Anthony Fauci over funding of bat-virus research by the National Institutes of Health. >>️

<< The NIH has still not fully explained its decision-making and did not reply to questions. Citing a pending investigation, it has declined to release copies of the grant that sent the Wuhan institute about $600,000 between 2014 and 2019. It has also revealed little about its new system for assessing gain-of-function risks, which is carried out by an anonymous review panel whose deliberations are not made public. >>️
Rowan Jacobsen. Inside the risky bat-virus engineering that links America to Wuhan. China emulated US techniques to construct novel coronaviruses in unsafe conditions. MIT TechRev. Jun 29, 2021. 


Also

<< " ... e Da-Li' si sparse pell' aere un fantasmatico ente supersintetico supercompresso ... >> in: ️2153 - cracker tendenziali (around a matter-sucking maelstrom). Notes. Apr 4, 2008. (quasi-stochastic poetry)


<< in attesa del beffardo tsunami. >> in: 1619 - onda di carambola. Notes. Nov 29, 2004. (quasi-stochastic poetry).

keyword 'virus' in Notes (quasi-stochastic poetry)


keyword 'virus' in FonT 


keyword 'caos' | 'caotico' in Notes (quasi-stochastic poetry)



FonT

no surprise, no amazement here, I know chickens behaviors. 

<< Ricordo che quando si era ragazzi, negli anni sessanta, ... >> in: 2157 - il pino di takata matsubara. Apr 1, 2011. Notes. 








mercoledì 20 gennaio 2016

# rmx-s-chem: a precise dance with 1 nm bubbles

<< ‘Bubble pen’ can precisely write patterns with nanoparticles as small as 1 nanometer >>

<< With this we might see the dawn of the nano machines >> (comment by  OranjeeGeneral, january 18, 2016)

http://www.kurzweilai.net/bubble-pen-can-precisely-write-patterns-with-nanoparticles-as-small-as-1-nanometer

L. Lin, X. Peng, et al.  Bubble-Pen Lithography. Nano Letters. Vol. 16: Issue. 1: Pages. 701-708. Publication Date (Web): December 17, 2015 DOI: 10.1021/acs.nanolett.5b04524

http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.5b04524

giovedì 10 settembre 2020

# gst: the dance (swimming and sinking behavior) of pelagic snails

<< Swimming and sinking behavior by pelagic snails is poorly studied but is important in their ecology, predator-prey interactions, and vertical distributions. >>

AA << focused on how the shell shape, body geometry, and body size affect their swimming behavior from a fluid mechanics perspective. In addition, ZooScan image analysis and metabarcoding of archived vertically stratified MOCNESS samples were used to relate swimming behaviors to night time and daytime vertical distributions. While different large scale swimming patterns were observed, all species exhibited small scale sawtooth swimming trajectories caused by reciprocal appendage flapping. Thecosome swimming and sinking behavior corresponded strongly with shell morphology and size, with the tiny coiled shell pteropods swimming and sinking the slowest, the large globular shelled pteropods swimming and sinking the fastest, and the medium-sized elongated shell pteropods swimming and sinking at intermediate speeds. However, the coiled shell species had the highest normalized swimming and sinking speeds, reaching swimming speeds of up to 45 body lengths s–1. The sinking trajectories of the coiled and elongated shell pteropods were nearly vertical, but globular shell pteropods use their hydrofoil-like shell to glide downwards at approximately 20° from the vertical, thus retarding their sinking rate. The swimming Reynolds number (Re) increased from the coiled shell species [Re ∼ O(10)] to the elongated shell species [Re ∼ O(100)] and again for the globular shell species [Re ∼ O(1000)], suggesting that more recent lineages increased in size and altered shell morphology to access greater lift-to-drag ratios available at higher Re. Swimming speed does not correlate with the vertical extent of migration, emphasizing that other factors, likely including light, temperature, and predator and prey fields, influence this ecologically important trait. Size does play a role in structuring the vertical habitat, with larger individuals tending to live deeper in the water column, while within a species, larger individuals have deeper migrations. >>

Ferhat Karakas, Jordan Wingate, et al. Swimming and Sinking Behavior of Warm Water Pelagic Snails. Front. Mar. Sci. doi: 10.3389/ fmars.2020.556239. Sep 7, 2020. 


<< And it's stunning to think that these sea butterflies are using the same fluid dynamics principles to fly through water that insects use to fly through air, >> David Murphy.

Poetry in motion: Engineers analyze the fluid physics of movement in marine snails. Frontiers. Sep 07, 2020


Also

<< Snails usually lumber along on their single fleshy foot; but not sea butterflies (Limacina helicina). These tiny marine molluscs gently flit around their Arctic water homes propelled by fleshy wings that protrude out of the shell opening. >>

These << snails swim using the same technique as flying insects, beating their wings in a figure-of-eight pattern,>>

Bizarre snail that swims like a flying insect. The Company of Biologists. Feb 17, 2016. 


David W. Murphy, Deepak Adhikari, et al. Underwater flight by the planktonic sea butterfly. Journal of Experimental Biology. 2016 219: 535-543. doi: 10.1242/jeb.129205. Feb 17, 2016.