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mercoledì 21 dicembre 2022
# gst: apropos of transitions, rich behaviors from chimeras or solitary states to traveling waves
martedì 13 giugno 2017
# s-gst: imaging a soliton, first in the centre (of the condensate) rather than at the edges
<< When a periodic waveform is subjected to small perturbations to its amplitude and phase, any nonlinearity in the system can lead to its fragmentation — a so-called modulation instability. The phenomenon often results in the formation of solitons — self-reinforcing solitary wave packets — aligned in a train >>
AA << found that [ in ultracold 7Li atoms ] solitons developed first in the centre of the condensate rather than at the edges, suggesting that the seed for the modulation instability is dominated by noise, which may be technical, thermal or quantum in origin >>
Yun Li. Ultracold gases. Search for the seed. doi:10.1038/nphys4172
http://www.nature.com/nphys/journal/v13/n6/full/nphys4172.html
Jason H. V. Nguyen, De Luo, Randall G. Hulet. Formation of matter-wave soliton trains by modulational instability. Science 2017, 356 (6336), 422–426. doi: 10.1126/science.aal3220. 28 Apr 2017.
lunedì 2 maggio 2016
# s-brain-evol: lizard, an ancient dreamer
<< Lizards might snooze like humans do. Sleeping lizards appear to share distinctive brain activity patterns with sleeping birds and mammals (..) If true, the results suggest that human sleep patterns evolved by around 300 million years ago in a common ancestor of birds, mammals and reptiles. >>
Sarah Schwartz. Dragons sleep like mammals and birds. Proof of reptiles’ slow-wave and REM cycle could alter understanding of slumber’s evolution. 2:19pm, April 28, 2016
https://www.sciencenews.org/article/dragons-sleep-mammals-and-birds
<< Sleep has been described in animals ranging from worms to humans. Yet the electrophysiological characteristics of brain sleep, such as slow-wave (SW) and rapid eye movement (REM) activities, are thought to be restricted to mammals and birds. Recording from the brain of a lizard, the Australian dragon Pogona vitticeps, we identified SW and REM sleep patterns, thus pushing back the probable evolution of these dynamics at least to the emergence of amniotes. The SW and REM sleep patterns that we observed in lizards oscillated continuously for 6 to 10 hours with a period of ~80 seconds. >>
Mark Shein-Idelson , Janie M. Ondracek, et al. Slow waves, sharp waves, ripples, and REM in sleeping dragons. Science 29 Apr 2016: Vol. 352, Issue 6285, pp. 590-595 DOI: 10.1126/science.aaf3621
martedì 31 ottobre 2023
# gst: how to create a helix from a straight rod, “twist” or “bend” approaches.
lunedì 22 gennaio 2024
# gst: the hypothesis of a new type of rogue waves.
mercoledì 8 maggio 2024
# gst: a case of noise-induced excitation wave (in coupled FH-N eq.)
martedì 5 aprile 2022
# gst: the solitary route to chimera states.
venerdì 14 aprile 2017
# s-gst: l'ineffabile duplice meccanica delle onde di Alfven
<< i dati raccolti da MMS [NASA's Magnetospheric Multiscale (MMS) mission] hanno consentito di osservare due tipi diversi di onde di Alfven. Da una parte, quelle cosiddette “tipiche”, dove le particelle cariche (..) sono libere di correre nel solco fra una cresta e l’altra delle onde del campo magnetico (..). Dall’altra, le onde di Alfven cinetiche, che muovendosi lungo il plasma intrappolano alcuni degli elettroni, facendoli rimbalzare avanti e indietro come fra due muri, o fra due specchi >>
Ecco come le onde di Alfven confinano le particelle. INAF TV. 10 apr 2017.
https://m.youtube.com/watch?v=z-SbeUpWCeQ&feature=youtu.be
Daniel J. Gershman, Adolfo F-Vinas, et al. Wave-particle energy exchange directly observed in a kinetic Alfven-branch wave. Nature Communications 8 , Article number: 14719 (2017) doi :10.1038/ncomms14719. Publ. 31 March 2017.
https://www.nature.com/articles/ncomms14719
Abhishek Kumar Srivastava, Juie Shetye, et al. High-frequency torsional Alfven waves as an energy source for coronal heating. Scientific Reports 7 , Article number: 43147 (2017). doi :10.1038/srep43147. Publ. online: 03 March 2017.
https://www.nature.com/articles/srep43147
also:
poetiche quasistocastiche circa forme d'onda, generiche e im-probabili senz'altro ...
sabato 13 aprile 2024
# gst: evolving disorder and chaos induces acceleration of elastic waves.
venerdì 10 luglio 2020
# gst: the physics of squeezing; how to squeeze out (quantum) noise
sabato 22 aprile 2023
# gst: when droplets are capable of self-propulsion as if they were surfing on a self-generated wave.
domenica 8 gennaio 2017
# s-ecol: a solitary Chemist against a "Cockroach Inverse Wave" hypothesis
<< La soglia minima per “bocciare” un dipendente è fissata a quota 50 punti, mentre a Genchi (dottor Gioacchino Genchi, chimico) era stata assegnata una valutazione di 58,01: in pratica mancavano i presupposti legali a supporto dell’ incredibile sanzione inibitoria, per il semplice fatto che il dipendente non aveva demeritato neanche nel punteggio che gli era stato assegnato dai suoi superiori. >>
Lino Buscemi. Sicilia, “sull’isola la matematica è relativa: lo strano caso del dottor Genchi”. F. Q. 7 Gen 2017
<< percio' e in definitiva se (beninteso, se e solo se) costui evitera' (#1) sara' per svista di dis tratto (#2) e non per altro ... >> Anonymous, XX e.V.
(#1): azzeramento
(#2): burocrate
sabato 5 dicembre 2015
# rmx-p-trade: Arezzo wave ...
<< Siamo le vittime di quel decreto non riesco più a dormire da giorni. Mi hanno preso i soldi (..) >>
<< (..) mi hanno fatto vedere un foglio, dei miei soldi non resta niente (..) >>
<< (..) la vecchietta di Arezzo viene di fatto trattata come quelli che giocavano in borsa con Cirio e Parmalat >>
<< Quando esco – racconta – la sento per strada la fatica, la rabbia. Persone che hanno perso tutto, i risparmi di una vita. Sì, temo contestazioni (..) >>
<< Se non mettiamo mano a questa cosa io ad Arezzo non ci posso mettere piede >>
04/12/2015 20:30 - http://m.huffpost.com/it/entry/8720770
http://corrierediarezzo.corr.it/news/economia/205326/Banca-Etruria--le-azioni-di.html
"Banca Etruria" site: http://corrierediarezzo.corr.it
mercoledì 13 gennaio 2016
# rmx-s-behav: a bizarre paddle game (about safety waves ...)
<< Males of a newly discovered species of jumping spider [Jotus remus] spend hours waving special paddle-shaped legs at prospective mates, in an effort to copulate without being attacked – or even eaten.
Mating can potentially cost you your life if you are a male spider. To avoid becoming lunch, Jotus remus plays a game first to tire out hungry females >>
https://www.newscientist.com/article/dn28756-male-spiders-lure-aggressive-females-with-peek-a-boo-paddle-game/
Jürgen C. Otto, David E. Hill. Males of a new species of Jotus from Australia wave a paddle-shaped lure to solicit nearby females (Araneae: Salticidae: Euophryini). PECKHAMIA 133.1, 7 January 2016, 1―39 urn:lsid:zoobank.org:pub:12A6DBBE-11EC-4DEB-9387-83F1AD727E6F (registered 6 JAN 2016) 1 ISSN 2161―8526 (print) ISSN 1944―8120 (online)
venerdì 4 febbraio 2022
# gst: apropos of apparent erratic dynamics, the self-organization of drops bouncing on a vertically-vibrated surface
venerdì 4 maggio 2018
# gst phys rmx : finding inspiration in atmospheric whistles (to stop particles to run away)
<< The challenge of fusion energy is often equated to capturing- and holding-lightning in a bottle. The analogy is apt. Lightning and a fusion energy plasma have a lot in common >> [1]
AA << found another characteristic shared between the two types of plasmas: an odd electromagnetic wave known as a whistler >> [1]
<< Intermittent bursts of activity indicate that whistlers are interacting with relativistic electrons in a cyclic manner >> [1]
<< The mode amplitudes show intermittent time variations correlated with changes in the electron cyclotron emission that follow predator-prey cycles >> [2]
<< the Team thinks there is a way to inject whistlers into a plasma to control runaway electrons. The whistlers would bleed energy from the particles, making them less likely to run away. The whistlers would bleed energy from the particles, making them less likely to run away.>> [1]
[1] - US Department of Energy. Fusion scientists find inspiration in atmospheric whistles. May 3, 2018. https://m.phys.org/news/2018-05-fusion-scientists-atmospheric.html
[2] - Spong DA, Heidbrink WW, et al. First Direct Observation of Runaway-Electron-Driven Whistler Waves in Tokamaks. Phys. Rev. Lett. 120, 155002 - Publ. Apr 11, 2018. https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.155002
sabato 8 settembre 2018
# gst: even repulsive interactions generate solitons
<< Solitons are nonspreading wave packets that exist in a wide range of real-world systems, including water waves, sound, DNA, optics, and so on. >>
<< Two or more solitons can bind together to form a soliton molecule with dynamics similar to matter molecules, such as vibration, synthesis, and dissociation. >>
<< Formation processes for three types of soliton molecules were studied: ground-, excited-state, and a new one termed an intermittent-vibration soliton molecule. While it is generally believed that attractive interactions of solitons are responsible for the formation of soliton molecules, the authors found that soliton interactions are not limited to attractive interactions. Counterintuitively, even repulsive interactions can lead to the formation of soliton molecules, >>
John Wallace. Investigation with a femtosecond fiber laser finds new type of soliton ‘molecule’. Aug 01, 2018.
<< For closely‐separated bound solitons, soliton interactions display wide diversities in repeated measurements, including soliton attraction, repelling, collision, vibration, and annihilation. For well‐separated bound solitons, repulsive interactions dominate the soliton interactions. >>
Junsong Peng, Heping Zeng. Build‐Up of Dissipative Optical Soliton Molecules via Diverse Soliton Interactions. Laser & Photonics Reviews 2018, 12, 1800009.
https://onlinelibrary.wiley.com/doi/pdf/10.1002/lpor.201800009
Also "soliton" in:
mercoledì 5 luglio 2023
# brain: spiral waves at the edge of neural tissue during cognitive processing.
mercoledì 10 aprile 2024
# gst: exploring the on-demand dynamical generation of a plethora of dispersive shock waves arising in attractive one-dimensional droplet-bearing environment.
domenica 31 gennaio 2016
# s-gene: Yoshizumi Ishino, Francisco Mojica (et al) wave: SRSR - CRISPR interference
<< We were stunned, it was like the sun rose in the west rather than the east.>> Ethan Bier
<< We’re not about to do anything foolish. >> Anthony James
Shelly Fanon. Gene Drives Could Wipe Out Insect-Borne Disease — But What’s the Price? Nov 29, 2015.
http://singularityhub.com/2015/11/29/gene-drives-can-eliminate-transmissible-diseases-for-good-but-whats-the-price
Yoshizumi Ishino and Francisco Mojica, in: CRISPR, Clustered regularly-interspaced short palindromic repeats.
https://en.m.wikipedia.org/wiki/CRISPR
Eric S. Lander. The Heroes of CRISPR.
Cell. 14 January 2016, Vol.164(1):18–28, doi:10.1016/j.cell.2015.12.041
http://www.sciencedirect.com/science/article/pii/S0092867415017055