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mercoledì 26 febbraio 2025

# gst: the sleeping bacterium, shedding light on the resuscitation mechanism.

<< The revival mechanism in dormant bacteria is a puzzling and open issue. (AA) propose a model of information diffusion on a regular grid where agents represent bacteria and their mutual interactions implement quorum sensing. Agents may have different metabolic characteristics corresponding to multiple phenotypes. The intra/inter phenotype cooperation is analyzed under different metabolic and productivity conditions. (AA) study the interactions between rapidly reproducing active bacteria and non-reproducing quiescent bacteria (thus) highlight the conditions under which the quiescent bacteria may revive. The occurrence of revival is generally related to a change in environmental conditions. (AA) results support this picture showing that revival can be mediated by the presence of different catalyst bacteria that produce the necessary resources. >>️

Eleonora Alfinito, Matteo Beccaria. The sleeping bacterium: shedding light on the resuscitation mechanism. arXiv: 2501.09366v1 [physics.bio-ph]. Jan 16, 2025.


Keywords: gst, pause, sleep, dormant, quiescence, resuscitation, bacterium 


lunedì 24 febbraio 2025

# gst: when homogeneous systems meet dissipation and disorder.

AA << investigate the localization and topological properties of the non-equilibrium steady state (NESS) in a one-dimensional homogeneous system. (Their) results demonstrate that, despite the absence of disorder in the initial system, the NESS can exhibit localization under bond dissipation. >>

<< Conversely, for an initially flat-band system with compactly localized wave functions, the NESS is delocalized. >>

<< Furthermore, (They) find that the initial localization characteristics of the system significantly influence the localization properties of the NESS. Drawing upon the concept of Bose-Einstein condensate broadening in cold-atom experiments, along with experimental data, (AA) systematically characterize the impact of disorder on the localization and topological properties of the NESS. >>

<< The phase diagram reveals that the NESS can be topologically non-trivial even when the initial state is topologically trivial, and that the topological triviality of the initial state weakens the topological non-triviality of the NESS. >>

Xixi Feng, Ao Zhou, et al. When Homogeneous Systems Meet Dissipation and Disorder. arXiv: 2502.11383v1 [cond-mat.dis-nn]. Feb 17, 2025. 

Also: order, disorder, disorder & fluctuations, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, order, disorder, disorder & fluctuations, transitions


domenica 23 febbraio 2025

# jazz. Got the Feeling. John McLaughlin, Jeff Beck. Live at Avery Fisher Hall, New York. Apr 30, 1975.

0:00​ Django 2002 
11:14​ Scatterbrain 2002 
15:48​ Manic Depression 1998 
23:11​ Power 1975 
28:54​ Early Led Boots/Power, Jam 1975 
37:58​ Diamond Dust, Jam 1975 
43:56​ Got the Feeling 1975 
1:07:49​ Django 1995 
1:15:12​ Cause We've Ended As Lovers 2023 

"Django" 
"Scatterbrain" 
live at the Royal Festival Hall on 14 September 2002. 
Tony Hymas on keyboards, Randy Hope-Taylor on bass, Stephen Barney on drums. Terry Bozzio (2nd drummer) and Aref Durvesh (tabla) joins on Scatterbrain! 
"Django" is a 1954 jazz standard written by John Lewis as a tribute to the Belgian-born jazz guitarist Django Reinhardt. 
    • Django  ​ from Django album by the Modern Jazz Quartet, released in 1956. 
    • Django  ​ from Evolution solo piano album by John Lewis, released in 1999. 
"Scatterbrain" written by Jeff Beck and Max Middleton. 
    • Scatterbrain  ​ originally from 1975 album Blow By Blow. 

"Manic Depression" 
live from Montreux Jazz Festival 1998. 
    • Manic Depression  ​ originally by Jimi Hendrix. 

"Power" 
live at Auditorium Theatre, Milwaukee, Wisconsin on 10 May 1975. 
Jeff Beck - Guitar, John McLaughlin - Guest Guitar, Wilbur Bascomb - Bass, Max Middleton - Keyboards, Bernard "Pretty" Purdie - Drums. 
    • Power  ​ originally by Stanley Clarke. 

"Early Led Boots/Power, Jam" 
"Diamond Dust, Jam" 
live at Reunion Arena, Dallas, Texas 11 June 1975. 
Jeff Beck as guest guitarist with Mahavishnu Orchestra. John McLaughlin: electric guitar, Ralphe Armstrong: electric bass, Stu Goldberg: keyboards, Steve Kindler: violin, Carol Shive: violin, Norma Jean Bell: saxophone, Premik Russel Tubbs: saxophone, Philip Hirschi: cello, Narada Michael Walden: drums. 
    • Led Boots  ​ from 1976 Wired album. 
    • Diamond Dust  ​ from 1975 Blow By Blow album. 

"Got the Feeling" 
live at Avery Fisher Hall, New York 30 April 1975. 
Jeff Beck - Guitar, John McLaughlin - Guest Guitar, Wilbur Bascomb - Bass, Max Middleton - Keyboards, Bernard Purdie - Drums. 
    • Got the Feeling  ​ from 1971 Rough And Ready album. 

"Django" 
Jeff Beck & John McLaughlin on guitars, Tony Hymas on keyboards, Pino Palladino on bass, Mark Mondesir on drums 
    • Django (Instrumental)  ​ from The Promise album by John McLaughlin, released in 1995. 

"Cause We've Ended As Lovers" 
live at Hanover, Germany 10th October 2023 by John McLaughlin Quintet: bassist Etienne Mbappe, drummer Ranjit Barot, pianist Jany McPherson and Gary Husband on keyboards. Written by Stevie Wonder. 
    • Cause We've Ended as Lovers  ​ from 1975 Blow By Blow album. 
    • Cause We've Ended As Lovers  ​ from 1974 Stevie Wonder Presents Syreeta album. 

@chromedreamer. Jul 6, 2024

Also: jazz, music, in https://www.inkgmr.net/kwrds.html 

Keywords: jazz, music


sabato 22 febbraio 2025

# gst: order and chaos in systems of coaxial vortex pairs

Fig. B.12: Ex. with 4 interact. vortex pairs

AA << have analyzed interactions between two and three coaxial vortex pairs, classifying their dynamics as either ordered or chaotic based on strengths, initial sizes, and initial horizontal separations.  >>️

They << found that periodic cases are scattered among chaotic ones across different initial configurations. Quasi-periodic leapfrogging typically occurs when the initial distances between the vortex pairs are small and cannot coexist with vortex-pair overtake. When the initial configuration splits into two interacting vortex pairs and a single propagating vortex pair, the two interacting pairs consistently exhibit periodic leapfrogging. For the smallest initial horizontal separations, the system predominantly exhibits chaotic or quasi-periodic motions rather than periodic leapfrogging with a single frequency. This behavior is due to the strong coupling between all three vortex pairs. When the pairs are in close proximity, more complex and chaotic dynamics emerge instead of periodic motion. >>

Their << findings indicate that quasi-periodic leapfrogging and chaotic interactions generally occur when the three vortex pairs have similar strengths and initial sizes. Conversely, discrepancies in these parameters cause the system to disintegrate into two subsystems: a single propagating vortex pair and two periodically leapfrogging pairs. >>️
Christiana Mavroyiakoumou, Wenzheng Shi. Order and Chaos in Systems of Coaxial Vortex Pairs. arXiv: 2502.07002v1 [physics.flu-dyn]. Feb 10, 2025. ️

Also: chaos, vortexorder, disorder, disorder & fluctuations, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, chaos, vortex, order, disorder, disorder & fluctuations


venerdì 21 febbraio 2025

# gst: apropos of nuanced dependencies in intricately coupled network, attractive-repulsive challenge in swarmalators with time-dependent speed.


AA << examine a network of entities whose internal and external dynamics are intricately coupled, modeled through the concept of ``swarmalators'' as introduced by O'Keeffe et al. (Nat. Commun., 8(1):1–13, 2017). (They) investigate how the entities' natural velocities impact the network's collective dynamics and path to synchronization. >>

<< Specifically, (AA) analyze two scenarios: one in which each entity has an individual natural velocity, and another where a group velocity is defined by the average of all velocities. >> 

Their << findings reveal two distinct forms of phase synchronization -- static and rotational -- each preceded by a complex state of attractive-repulsive interactions between entities. This interaction phase, which depends sensitively on initial conditions, allows for selective modulation within the network. By adjusting initial parameters, (AA) can isolate specific entities to experience attractive-repulsive interactions distinct from the group, prior to the onset of full synchronization. >>

<< This nuanced dependency on initial conditions offers valuable insights into the role of natural velocities in tuning synchronization behavior within coupled dynamic networks. >>️

Steve J. Kongni, Thierry Njougouo, et al. Attractive-repulsive challenge in swarmalators with time-dependent speed. arXiv: 2501.06048v1 [nlin.AO]. Jan 10, 2025. 

Also: swarm, network, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, swarm, swarmalators, network


giovedì 20 febbraio 2025

# gst: friction-induced bubble edge curvature in flowing 2D confined foams

AA << investigate the flow of quasi-2D liquid foams, composed of a single monolayer of bubbles in close contact and confined between two glass plates in a Hele-Shaw cell, with a specific emphasis on understanding how bubble shapes evolve in response to varying flow speeds. Utilizing an experimental setup capable of displacing a substantial number of bubbles in the spanwise direction, while the bubble shapes remain stationary as the bubbles themselves are advected in a plug flow, (They) reveal an average bubble anisotropy characterized by elongated bubbles in the streamwise direction and curved bubble edges in a preferential orientation. >>

<< Notably, these effects intensify with increasing flow speeds. While the bubble anisotropy is created at the entrance of the cell, (AA) study establishes a clear connection between bubble edge curvature and orientation, confinement thickness, frictional forces with the plates, and the inherent anisotropy of the bubbles. >>

Christophe Raufaste, Lauren Rose, et al. Friction-induced bubble edge curvature in flowing two-dimensional confined foams. Phys. Rev. Fluids 10, 023301. Feb 5, 2025. 

Also: bubble, foam, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, bubble, foam, friction, surface tension

mercoledì 19 febbraio 2025

# gst: alignment-induced self-organization of autonomously steering microswimmers: turbulence, clusters, vortices, and jets.


<< Microorganisms can sense their environment and adapt their movement accordingly, which gives rise to a multitude of collective phenomena, including active turbulence and bioconvection. In fluid environments, collective self-organization is governed by hydrodynamic interactions. >>

<< By large-scale mesoscale hydrodynamics simulations, (AA) study the collective motion of polar microswimmers, which align their propulsion direction by hydrodynamic steering with that of their neighbors. The simulations of the employed squirmer model reveal a distinct dependence on the type of microswimmer—puller or pusher—flow field. No global polar alignment emerges in both cases. Instead, the collective motion of pushers is characterized by active turbulence, with nearly homogeneous density and a Gaussian velocity distribution; strong self-steering enhances the local coherent movement of microswimmers and leads to local fluid-flow speeds much larger than the individual swim speed. >>

<< Pullers exhibit a strong tendency for clustering and display velocity and vorticity distributions with fat exponential tails; their dynamics is chaotic, with a temporal appearance of vortex rings and fluid jets. >>

AA << results show that the collective behavior of autonomously steering microswimmers displays a rich variety of dynamic self-organized structures. >>

Segun Goh, Elmar Westphal, et al. Alignment-induced self-organization of autonomously steering microswimmers: Turbulence, clusters, vortices, and jets. Phys. Rev. Research 7, 013142. Feb 7, 2025. 

Also: swim, microswimmer, particle, turbulencechaos, noise, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, swim, swimmer, microswimmers, particle, turbulence, chaos, noise