flashontrack

lunedì 8 luglio 2019

# phys: optical vortex to probe magnetism in matter

<< A light "corkscrew" is sensitive to the local magnetic field direction, so it can be used to probe magnetism in a material. >>

<< Circularly polarized light can act as a powerful probe of magnetism in matter. By measuring differences in the transmission of light beams polarized in different directions as they pass through a material, physicists can unravel atomic-level details of the material’s magnetic properties. >>

Synopsis: Optical Vortices Can Probe Magnetism. Jun 12, 2019.

https://physics.aps.org/synopsis-for/10.1103/PhysRevLett.122.237401

A. A. Sirenko, P. Marsik, et al. Terahertz Vortex Beam as a Spectroscopic Probe of Magnetic Excitations. Phys. Rev. Lett. 122, 237401. Jun 12, 2019.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.122.237401

sabato 6 luglio 2019

# brain: short-term exercise enhances brain function

<< Exercise is cheap, and you don't necessarily need a fancy gym membership or have to run 10 miles a day, >> Gary Westbrook

AA << designed a study in mice that specifically measured the brain's response to single bouts of exercise in otherwise sedentary mice that were placed for short periods on running wheels. The mice ran a few kilometers in two hours. >>

<< short-term bursts of exercise- the human equivalent of a weekly game of pickup basketball, or 4,000 steps- promoted an increase in synapses in the hippocampus. Scientists made the key discovery by analyzing genes that were increased in single neurons activated during exercise. >>

<< One particular gene stood out: Mtss1L. This gene had been largely ignored in prior studies in the brain. >>

Study reveals a short bout of exercise enhances brain function. Oregon Health & Science University. Jul 3, 2019.

https://m.medicalxpress.com/news/2019-07-reveals-short-bout-brain-function.html

AA << results link short-term effects of exercise to activity-dependent expression of Mtss1L, which propose as a novel effector of activity- dependent rearrangement of synapses. >>

Christina Chatzi, Yingyu Zhang, et al. Exercise-induced enhancement of synaptic function triggered by the inverse BAR protein, Mtss1L. eLife 2019; 8: e45920. doi: 10.7554/eLife.45920. Jun 24, 2019

https://elifesciences.org/articles/45920

venerdì 5 luglio 2019

# cells: liver tissue as a 'liquid-crystal' structure

<< analysis of the spatial organization of cell polarity revealed that hepatocytes are not randomly oriented but follow a long-range liquid crystal order. >>

New modeling technique discovers surprising 'liquid-crystal' organization of liver tissue. Max Planck Society. Jul 3, 2019.

https://m.medicalxpress.com/news/2019-07-technique-liquid-crystal-liver-tissue.html

Hernan Morales-Navarrete, Hidenori Nonaka, et al. Liquid-crystal organization of liver tissue. eLife. doi: 10.7554/eLife.44860. Jun 17, 2019.

https://elifesciences.org/articles/44860

giovedì 4 luglio 2019

# gst: when two like-charged spherical metal nanoparticles with unequal charges counterintuitively will attract one another.

<< When it comes to electric charge, there is one overriding theme: opposites attract, and like charges repel. But in a new study, physicists have made the surprising discovery that two spherical like-charged metal nanoparticles with unequal charges can attract one another in a dilute electrolyte solution. The reason, in short, is that the more strongly charged nanoparticle polarizes the metal core of the weakly charged nanoparticle, which alters the interaction between the nanoparticles. >>

<< Our paper elucidates a very counterintuitive behavior which was previously thought to be impossible, >> Yan Levin.

Lisa Zyga. A counterintuitive case in which like charges attract. Phys.org. Jul 2, 2019.

https://m.phys.org/news/2019-07-counterintuitive-case.html

Alexandre P. dos Santos, Yan Levin. Like-Charge Attraction between Metal Nanoparticles in a 1∶ 1 Electrolyte Solution. Phys. Rev. Lett. 122, 248005. June 21, 2019.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.122.248005

martedì 2 luglio 2019

# gst: apropos of freezing bubbles ...

<< Droplets or puddles tend to freeze from the propagation of a single freeze front. In contrast, videographers have shown that as soap bubbles freeze, a plethora of growing ice crystals can swirl around in a beautiful effect visually reminiscent of a snow globe. >>

AA << characterize the physics of soap bubbles freezing on an icy substrate and reveal two distinct modes of freezing. The first mode, occurring for isothermally supercooled bubbles, generates a strong Marangoni flow that entrains ice crystals to produce the aforementioned snow globe effect. The second mode occurs when using a cold stage in a warm ambient, resulting in a bottom-up freeze front that eventually halts due to poor conduction along the bubble. >>

S. Farzad Ahmadi, Saurabh Nath, et al. How soap bubbles freeze. Nature Communications. volume 10, Article number: 2531. Jun 18, 2019.

https://www.nature.com/articles/s41467-019-10021-6

Rosaire Bushey. Freezing bubbles viral video inspired research now published. Virginia Tech. Jun 19, 2019.

https://m.phys.org/news/2019-06-viral-video-published.html

lunedì 1 luglio 2019

# brain: naturally-occurring psychedelic DMT, a 'magic string' endogenously synthesized

AA << results show for the first time that the rat brain is capable of synthesizing and releasing DMT [N,N-dimethyltryptamine] at concentrations comparable to known monoamine neurotransmitters and raise the possibility that this phenomenon may occur similarly in human brains. >>

Jon G. Dean, Tiecheng Liu, et al. Biosynthesis and Extracellular Concentrations of N,N- dimethyltryptamine (DMT) in Mammalian Brain. Scientific Reports. volume 9, Article number: 9333 (2019). Jun 27, 2019.

https://www.nature.com/articles/s41598-019-45812-w

'Mystical' psychedelic compound found in normal brains. University of Michigan. Jun 27, 2019.

https://m.medicalxpress.com/news/2019-06-mystical-psychedelic-compound-brains.html

Also

'magic strings', in: FonT

https://flashontrack.blogspot.com/search?q=magic+strings

sabato 29 giugno 2019

# brain: immagini #CTZ, cicliche fantasmatiche pervasive visioni ricorrenti

<< Vladimir Putin has trumpeted the growth of national populist movements in Europe and America, crowing that liberalism is spent as an ideological force.

In an FT interview in the Kremlin on the eve of the G20 summit in Osaka, Japan, the Russian president said “the liberal idea” had “outlived its purpose” as the public turned against immigration, open borders and multiculturalism. >>

Lionel Barber and Henry Foy in Moscow, and Alex Barker in Osaka. Vladimir Putin says liberalism has 'become obsolete'. FT. Jun 27, 2019

https://www.ft.com/content/670039ec-98f3-11e9-9573-ee5cbb98ed36

FonT

i giochi fisiologici che si giocano su questo pianeta (forse anche altrove) sono giochi 'aperti', all'interno dei due vincoli del gioco 'legale' (sostanzialmente i due vincoli del casino' [#1,#2]); al di fuori dei due vincoli non c'e' auto-struttura, auto-funzione, auto- manutenzione, e dove non c'e' auto- manutenzione la speranza di sopravvivenza - in funzione del tempo - di qualsivoglia sistema vivente cala, smorza, scema, declina; questa sembra la realta' funzionale di un sistema complesso dove le interne sub-unita' sono in continua interazione (non lineare); la propensione di entita' CTZ sensibili, specialmente quando costrette a fronteggiare bi/ multi- forcazioni, di ricondurre i punti di riferimento decisionali alle classiche, storiche, rituali tre 'immagini' (CTZ, appunto) - il 'Campanile', la 'Terra', la 'Zappa' (da li' l'anagramma: 'ne Campa il ZappaTerra') - e' sostanzialmente illusoria perche' i tre punti di riferimento CTZ non permettono all'entita' transeunte di risolvere / reimpostare in modo soddisfacente i suoi problemi, veri o presunti tali; talvolta si ha l'illusione di una risoluzione, che sara' tuttavia irreversibilmente instabile rispetto al tempo; il Campanile e' una immagine che per sua intima natura e' relativa, le teoretiche che lo giustificano, lo sostengono, hanno contorni s-fumati, che scricchiolano (evaporano) dalle troppe contraddizioni interne; la Terra 'trema', anch'essa per sua intima natura, e' transitoria, si incendia, congela, sbricciola, frana, si allaga, viene spazzata periodicamente da vortici d'aria, e' sensibile a imponenti forze esterne, cosmologiche, percio' partecipa attivamente alla compromissione della stabilita' di qualsivoglia Campanile (Totem, Lampione ...); la Zappa e' per sua intima natura un oggetto 'techno', dipende dallo stato dell'arte tecno-scientifica, e attualmente e' in mutazione verso le graziose forme del 'robota', oggetto prospetticamente autonomo, fisicamente, neuralmente (culturalmente?) ...

Il bravo (e fortunato) dr. Albert - Albert Hofmann, chimico con il pallino dell'azzardo sperimentale, un classico ... - aveva forse trovato il giusto approccio, la giusta 'medicina' per offrire 'respiro' anche a lungo termine alle moltitudini entita' CTZ-dipendenti (neuralmente, geneticamente dipendenti?), specialmente se e quando coinvolte in contesti di accidentale modalita' accelerativa transeunte; e' davvero disdicevole che la molecola di Hofmann (LSD [#3]) presenti effetti collaterali non insignificanti; se gli effetti 'epigenetici' sono fisiologicamente troppo lenti per fronteggiare una realta' mutaforma dirompente e pervasiva, allora forse servirebbe una nuova 'magica stringa' [#4] farmacologica o di natura genetica, farmaco-epigenetica, allo scopo di alleviare almeno quegli stati confusionali, depressivi e i comportamenti a-priori lesivi- autolesivi tipici dell'entita' CTZ-dipendenti; anche e senz'altro per quell'altre entita', ben mimetizzate, a loro dire solo apparentemente illusoriamente insensibili a visioni / vincoli CTZ.

Davvero disdicevole accadimento (per i non pochi) lo storico 'salto' dallo 'standard' entita' nomade esploratrice erratica verso il qualcos'altro, ... non e' vero?

[#1] - Notes. 1809 - strutturanti decisioni. Nov 26, 2004.

https://inkpi.blogspot.com/2004/11/1809-strutturanti-decisioni.html

[#2] - Notes. 1821 - i due beffardi vincoli. Nov 26, 2004.

https://inkpi.blogspot.com/2004/11/1821-i-due-beffardi-vincoli.html

[#3] - 'LSD' in: FonT.

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

[#4] - 'magic string' in: FonT. An ethno-drug revisited ... Ayahuasca, prelude of a "magic string" in neuropharmacology. Jul 8, 2018.

https://flashontrack.blogspot.com/2018/07/pharma-ethno-drug-revisited-ayahuasca.html