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

giovedì 22 aprile 2021

# life: cascading effects of noise on plants

<< Though noise may change moment by moment for humans, it has a more lasting effect on trees and plants. (..) human noise pollution affects the diversity of plant life in an ecosystem even after the noise has been removed. This is the first study that explores the long-term effects of noise on plant communities. >>
Cascading effects of noise on plants persist over long periods and after noise is removed. California Polytechnic State University. Apr 13, 2021. 


AA << found support for long-term negative effects of noise on tree seedling recruitment, evenness of woody plants and increasingly dissimilar vegetation communities with differences in noise levels. Furthermore, seedling recruitment and plant community composition did not recover following noise removal, possibly due in part to a lag in recovery among animals that disperse and pollinate plants. (They) results add to the limited evidence that noise has cascading ecological effects. Moreover, these effects may be long lasting and noise removal may not lead to immediate recovery. >>
Jennifer N. Phillips, Sarah E. Termondt, Clinton D. Francis.  Long-term noise pollution affects seedling recruitment and community composition, with negative effects persisting after removal. Proceedings of the Royal Society B. doi: 10.1098/ rspb.2020.2906. Apr 14, 2021.


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keyword 'noise' in FonT






lunedì 28 giugno 2021

# gst: synchronous dynamics by uncorrelated noise

<< Synchronization is a widespread phenomenon observed in physical, biological, and social networks, which persists even under the influence of strong noise. Previous research on oscillators subject to common noise has shown that noise can actually facilitate synchronization, as correlations in the dynamics can be inherited from the noise itself. However, in many spatially distributed networks, such as the mammalian circadian system, the noise that different oscillators experience can be effectively uncorrelated. >>️

<< Here, (AA) show that uncorrelated noise can in fact enhance synchronization when the oscillators are coupled. Strikingly, (their) analysis also shows that uncorrelated noise can be more effective than common noise in enhancing synchronization. >>️

Zachary G. Nicolaou, Michael Sebek, et al. Coherent Dynamics Enhanced by Uncorrelated Noise. Phys. Rev. Lett. 125, 094101. Aug 24, 2020  



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keyword 'error' | 'fuzzy' | 'noise'  in FonT 




keywords 'errore' | 'errori' in Notes (quasi-stochastic poetry)



keywords 'jelly roll' in Notes (quasi-stochastic poetry)





sabato 9 febbraio 2019

# gst: (you must) read the noise as a message

<< Noise is often thought to be a nuisance with negative consequences, (..)  But through this study we show that noise can actually be used as a salient informational cue. It can provide individuals with important information about their environment and when it's safe to hunt. >> Inga Geipel

When does noise become a message?  Smithsonian Tropical Research Institute. Feb 6, 2019.

https://m.phys.org/news/2019-02-noise-message.html

<< Background noise can have strong negative consequences for animals, reducing individual fitness by masking communication signals, impeding prey detection and increasing predation risk. While the negative impacts of noise across taxa have been well documented, the use of noise as an informational cue, providing animals with reliable information on environmental conditions, has been less well studied. >>

Inga Geipel, Marcus J. Smeekes, et al. Noise as an informational cue for decision-making: the sound of rain delays bat emergence. Journal of Experimental Biology 2019 222: jeb192005 doi: 10.1242/jeb.192005 Feb 1, 2019.

http://jeb.biologists.org/content/222/3/jeb192005

Also

"noise" | "rumore"

https://inkpi.blogspot.com/search?q=noise

https://inkpi.blogspot.com/search?q=rumore

mercoledì 9 settembre 2020

# gst: to reach detectability of a weak signal, they add background noise

<< In contrast to most sensors, for which noise is a problem that should be suppressed, (AA) found that adding just the right amount of background noise can actually increase a signal too weak for sensing by normal sensors, to a level that can reach detectability. >>

Walt Mills. To make a better sensor, just add noise. Pennsylvania State University. Sep 03, 2020. 


<< In this article, (AA) adopt a radical approach for next generation ultra-low-power sensor design by embracing the evolutionary success of animals with extraordinary sensory information processing capabilities that allow them to survive in extreme and resource constrained environments. Stochastic resonance (SR) is one of those astounding phenomena, where noise, which is considered detrimental for electronic circuits and communication systems, plays a constructive role in the detection of weak signals. >>

Akhil Dodda, Aaryan Oberoi, et al. 
Stochastic resonance in MoS2 photodetector. Nat Commun 11, 4406 (2020). doi: 10.1038/ s41467-020-18195-0. Sep 2, 2020.


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keyword 'noise' in FonT


Also 

plus ambiguity and noise. Notes. Jul 06, 2007  (quasi-stochastic poetry)




martedì 19 novembre 2019

# gst: measuring biological noise of gene expression

<< Essential genes are often expressed with high variability during the development of cells. Scientists call this phenomenon "biological noise" and suspect that it is also decisive for the fate of cells, i.e. the developmental pathway a cell takes. Max Planck researcher Dominic Grun now presents a method based on single-cell data to quantify this variability in gene expression.  >>

Dominic Grun << hopes to gain a better understanding of the extent to which noise regulates development or is even necessary for the differentiation of cells. >>

How gene expression noise shapes cell fate. Max Planck Society. Nov 18, 2019. 

https://m.phys.org/news/2019-11-gene-noise-cell-fate.html   

Grun D. Revealing dynamics of gene expression variability in cell state space. Nat Methods (2019) doi:10.1038/s41592-019-0632-3. Nov 18, 2019.

https://www.nature.com/articles/s41592-019-0632-3

Also

keyword 'noise' in Notes:

https://inkpi.blogspot.com/search?q=noise

keyword 'noise' in FonT:

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



mercoledì 18 maggio 2022

# brain: jazzy perceptions inside, there’s more to all the noise; even in the dark, neurons of the visual cortex chat

<< Scientists are now rethinking how they study and conceive of perception. >>

<< At every moment, neurons whisper, shout, sputter and sing, filling the brain with a dizzying cacophony of voices. Yet many of those voices don’t seem to be saying anything meaningful at all. They register as habitual echoes of noise, not signal; as static, not discourse. >>️

<< But over the past decade, that view has changed. (..) There’s more to all the noise, scientists realized, than they had assumed. >>️

<< Now, by analyzing both the neural activity and the behavior of mice in unprecedented detail, researchers have revealed a surprising explanation for much of that variability: Throughout the brain, even in low-level sensory areas like the visual cortex, neurons encode information about far more than their immediately relevant task. They also babble about whatever other behaviors the animal happens to be engaging in, even trivial ones — the twitch of a whisker, the flick of a hind leg. Those simple gestures aren’t just present in the neural activity. They dominate it. >>️

<< Our brains aren’t just thinking in our heads. Our brains are interacting with our bodies and the way that we move through the world. >> Cris Niell. 

<< Wait — maybe the brain isn’t noisy. Maybe it’s actually much more precise than we thought, >> David McCormick️.️

Jordana Cepelewicz. ‘Noise’ in the Brain Encodes Surprisingly Important Signals. Quantamag. Nov 7, 2019. 


Salkoff DB, Zagha E, McCarthy E, McCormick DA. Movement and Performance Explain Widespread Cortical Activity in a Visual Detection Task. Cereb Cortex. 2020 Jan 10;30(1):421-437. doi: 10.1093/ cercor/bhz206. 


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keyword 'perception' in FonT


keyword 'percezione' | 'percezioni' in Notes (quasi-stochastic poetry)



keyword 'error' | 'fuzzy' | 'noise'  in FonT 




keywords 'errore' | 'errori' in Notes (quasi-stochastic poetry)



keyword 'jazz' in FonT


keyword 'jazz' in Notes (quasi-stochastic poetry):


Keywords: brain, perception, visual cortex, noise









sabato 16 dicembre 2023

# gst: correlated noise and critical dimensions.

<< In equilibrium, the Mermin-Wagner theorem prohibits the continuous symmetry breaking for all dimensions d≤2. In this work, (AA) discuss that this limitation can be circumvented in nonequilibrium systems driven by the spatiotemporally long-range anticorrelated noise. >>

<< results suggest that the critical dimensions increase when the noise is positively correlated in space and time and decrease when anticorrelated. (AA)  also report that the spherical model with the correlated noise shows the hyperuniformity and giant number fluctuation even well above the critical point. >>️

Harukuni Ikeda. Correlated noise and critical dimensions. Phys. Rev. E 108, 064119. Dec 13, 2023.

Also: noise, fluctuations, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, noise, fluctuations


lunedì 26 agosto 2019

# gst: the hypothesis to optimize multiplicative noise to enhance a signal-to-noise ratio

AA << study simple integrate-and-fire type models with multiplicative noise and consider the transmission of a weak and slow signal, >>

<< The specific question of interest is whether and how the state-dependence of the noise can be optimized with respect to information transmission >>

<< also in a biophysically more relevant situation, multiplicative noise can enhance the signal-to-noise ratio (..) results shed light on a so far unexplored aspect of stochastic signal transmission in neural systems. >>

Jonathan Bauermann Benjamin Lindner. Multiplicative noise is beneficial for the transmission of sensory signals in simple neuron models. Biosystems. Volume 178, Apr 2019, Pages 25-31. doi: 10.1016/ j.biosystems.2019.02.002

https://www.sciencedirect.com/science/article/pii/S0303264718303861

venerdì 26 maggio 2023

# gst: even a tiny noise could self-induce new chimera patterns through stochastic resonance


<< Noise induced order in excitable systems has diverse manifestations, such as coherence resonance (CR) and stochastic resonance. In this context a less explored phenomenon is self-induced stochastic resonance (SISR). Unlike CR, SISR may arise away from the bifurcation threshold and the properties of the induced oscillations depend upon both the noise intensity and the time-scale separation factor. In this work, (AA) report a new chimera pattern in a network of coupled excitable units, namely the self-induced stochastic resonance chimera or SISR-chimera that originates from the SISR phenomenon. (AA) explore the detailed dynamics of the SISR-chimera in the parameter space using proper quantitative measures. (AA) have found that unlike CR chimera, the SISR-chimera pattern strongly depends upon the ratio of time scale and noise intensity. Therefore, this type of chimera pattern can be induced even for a tiny noise intensity if the time scale separation of the activator and inhibitor is large enough. >>️

Taniya Khatun, Tanmoy Banerjee. Genesis of chimera patterns through self-induced stochastic resonance. arXiv:2305.06824v1 [nlin.AO]. May 11, 2023. 

Also:  chimera, noise, disorder in  https://www.inkgmr.net/kwrds.html  

Keywords: gst, noise, disorder, chimera, self-induced stochastic resonance chimera 




venerdì 22 ottobre 2021

# gst: the effect of noise on the dynamics of microswimmers in externally-driven fluid flows.

AA << have quantified the effect of noise on swimmer dynamics in a steady, two-dimensional hyperbolic fluid flow. In such a flow, swimmers are ultimately forced to escape to the left or the right, with their transient dynamics near the passive unstable fixed point determining which way they go. >>

<< Without noise, a swimmer’s fate is sealed based on its position relative to the SwIM (swimming invariant manifolds) in the xθ phase space. With noise, the swimmer’s motion is a stochastic process. >>

AA << calculated the steady-state orientation distributions of diffusive, run-and-tumble, or mixed swimmers in the hyperbolic flow. The fluctuations give some swimmers greater opportunity to cross the SwIM and exit on the opposite side than they would have without noise. There is however a maximal distance that swimmers can get on either side of the passive fixed point and still be able to swim back to the other side—this is where the stable BIMs (burning invariant manifolds) block inward swimming particles. >>

<< Fluctuations make it increasingly likely that a swimmer close to one of these BIMs does indeed end up crossing it, causing irreversible changes to the fluctuating swimmers’ trajectories (assuming negligible translational diffusion).  >>️

Simon A. Berman, Kevin A. Mitchell. Swimmer dynamics in externally-driven fluid flows: The role of noise. arXiv: 2108.10488v1 [physics.flu-dyn]. Aug 24, 2021.


keywords: gst, swimmer, swimming particle, fluid dynamics, chaotic dynamics, rotational diffusion, random fluctuation, tumbling, noise


venerdì 10 luglio 2020

# gst: the physics of squeezing; how to squeeze out (quantum) noise

<< 'Squeezing' is used in physics, among other things, to improve the resolution of measuring instruments. It allows disturbing noise to be suppressed in a way that smaller signals can be detected more sensitively. (..) (AA) has now been able to show how such a squeezed state can be measured in a much simpler way than with the existing methods. Moreover, the new method allows examining squeezed states in systems where such measurements were not possible before. >> [1]

<< In the experiment (..) the thermal fluctuations of a vibrating nanomechanical string resonator are squeezed. The nanostring can be thought of as a tiny guitar string, a thousand times thinner and shorter than a human hair. (..)  If the string is deflected far enough, it ceases to behave linearly. This means that the force that deflects the string is no longer proportional to the force that pulls it back to its original position. The strong drive alters the thermal fluctuations as a result of a violation of the time reversal symmetry. In phase space, they no longer look like a circle but like an ellipse: At least in one direction, its diameter, i.e. the noise, becomes significantly smaller—it is squeezed. >> [1]

<< Quantum squeezing was a theory that was first proposed in the 1980s, the general idea being that quantum vacuum noise can be represented as a sphere of uncertainty along two main axes: phase and amplitude. If this sphere were squeezed, like a stress ball, in a way that constricted the sphere along the amplitude axis, this would in effect shrink the uncertainty in the amplitude state of a vacuum (the squeezed part of the stress ball), while increasing the uncertainty in the phase state (stress ball's displaced, distended portion). Since it is predominantly the phase uncertainty that contributes noise to LIGO, shrinking it could make the detector more sensitive to astrophysical signals. (..) The heart of the squeezer is an optical parametric oscillator, or OPO — a bowtie-shaped device that holds a small crystal within a configuration of mirrors. When the researchers direct a laser beam to the crystal, the crystal's atoms facilitate interactions between the laser and the quantum vacuum in a way that rearranges their properties of phase versus amplitude, creating a new, "squeezed" vacuum that then continues down each of the detector's arm as it normally would. This squeezed vacuum has smaller phase fluctuations than an ordinary vacuum, allowing scientists to better detect gravitational waves. >> [2]

[1] - Measure squeezing in a novel way. University of Konstanz. Jun 25, 2020.   https://phys.org/news/2020-06-measure-squeezing-in-a-novel.html
J. S. Huber, G. Rastelli, et al. Spectral Evidence of Squeezing of a Weakly Damped Driven Nanomechanical Mode.  Phys. Rev. X 10, 021066 – Jun 23,  2020.   https://journals.aps.org/prx/abstract/10.1103/PhysRevX.10.021066 

[2] - Jennifer Chu. New instrument extends LIGO’s reach. Technology "squeezes" out quantum noise so more gravitational wave signals can be detected. MIT. Dec 5, 2019.   https://news.mit.edu/2019/ligo-reach-quantum-noise-wave-1205





lunedì 10 ottobre 2022

# gst: apropos of transitions, escape inside a noisy layered system

<< Noisy layered systems can exhibit amplified fluctuation patterns depending on their connectivity. Here (AA) showed that noise originally injected in one layer may induce faster basin escape in connected layers. This is both due to the amplification of the noise amplitude and the system specific correlations that the noise acquire while going through the first layer. Indeed, (..) one sees that the noise in the second is correlated in both space and time with clear dependence on the network structure. For networks with low algebraic connectivity, (AA) numerically showed that the first escape time is shorter in the two cases where (i) fluctuations are amplified in the second layer and (ii) noise in the second layer is rescaled in order to have the same variance in both layers. While point (i) is rather intuitive, i.e. larger fluctuations lead to shorter first escape times, point (ii) is more involved. Indeed, this indicates that noise with spatial and temporal correlations (..) selects directions that enable faster exits from the initial basin of attraction. >>

Melvyn Tyloo. Faster network disruption from layered oscillatory dynamics. arXiv: 2210.01180v1 [nlin.AO]. Oct 3, 2022. 

Also

keyword 'escape' in FonT


keyword 'escape' | 'fuga' in Notes 
(quasi-stochastic poetry)



Keywords: gst, transitions, escape, noise, noisy layered systems 


mercoledì 17 agosto 2022

# gst: rare transitions in noisy net scenarios


AA << study small white noise perturbations of planar dynamical systems with heteroclinic networks in the limit of vanishing noise. (They)  show that the probabilities of transitions between various cells that the network tessellates the plane into decay as powers of the noise magnitude. (They) show that the most likely scenario for the realization of these rare transition events involves spending atypically long times in the neighborhoods of certain saddle points of the network. >>️

Yuri Bakhtin, Hong-Bin Chen, Zsolt Pajor-Gyulai. Rare transitions in noisy heteroclinic networks. arXiv: 2205.00326v1 [math.PR]. Apr 30, 2022.    https://arxiv.org/abs/2205.00326

Also

keyword 'noise'  in FonT 

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

Keywords: gst, transitions, networks, heteroclinic networks, noise


mercoledì 6 settembre 2023

# gst: chimera resonance, in analogy with the effects of stochastic and coherence resonance


AA << explore numerically the impact of additive Gaussian noise on the spatio-temporal dynamics of ring networks of nonlocally coupled chaotic maps. >>
<<  It is shown that the coupling strength range can be the widest at a certain optimum noise level at which chimera states are observed with a high probability for a large number of different realizations of randomly distributed initial conditions and noise sources. >>

<< This phenomenon demonstrates a constructive role of noise in analogy with the effects of stochastic and coherence resonance and may be referred to as chimera resonance. >>️

Elena Rybalova, Vasilii Nechaev, Eckehard Schöll, Galina Strelkova. Chimera resonance in networks of chaotic maps. arXiv:2307.00006v2 [cond-mat.dis-nn]. Jul 5, 2023.

Also: chimera, noise, chaos, network,  in: https://www.inkgmr.net/kwrds.html

Keywords: gst, chimera, noise, chaos, network, chimera resonance





martedì 17 ottobre 2023

# game: noise-induced Parrondo's paradox in discrete-time qu-walks

<< Parrondo's paradox refers to the apparently paradoxical effect whereby two or more dynamics in which a given quantity decreases are combined in such a way that the same quantity increases in the resulting dynamics. >>

AA << show that noise can induce Parrondo's paradox in one-dimensional discrete-time quantum walks with deterministic periodic as well as aperiodic sequences of two-state quantum coins where this paradox does not occur in the absence of noise. >>️

Zbigniew Walczak, Jarosław H. Bauer. Noise-induced Parrondo's paradox in discrete-time quantum walks. Phys. Rev. E 108, 044212. Oct 11, 2023.

Also: parrondo, walk, noise, in: https://www.inkgmr.net/kwrds.html

Keywords: games, parrondo, walk, noise




sabato 5 agosto 2023

# gst: tipping in a low-dimensional model of a (tropical) cyclone.


 <<Tipping is the rapid, and often irreversible, change in the state of a system [Ashwin P. et al (2017)] >> 

AA << present a case study of both rate and noise-induced tipping between the stable states, relating to the destabilization or formation of a tropical cyclone. While the stochastic system exhibits transitions both to and from the non-storm state, noise-induced tipping is more likely to form a storm, whereas rate-induced tipping is more likely to be the way a storm is destabilized, and in fact, rate-induced tipping can never lead to the formation of a storm when acting alone. For rate-induced tipping acting as a destabilizer of the storm, a striking result is that both wind shear and maximal potential velocity have to increase, at a substantial rate, in order to effect tipping away from the active hurricane state. For storm formation through noise-induced tipping, (AA) identify a specific direction along which the non-storm state is most likely to get activated. >> 

Katherine Slyman, John A. Gemmer, et al. Tipping in a Low-Dimensional Model of a Tropical Cyclone. arXiv: 2307.15583v1 [math.DS]. Jul 28, 2023.
 
Also: vortex, instability, noise, in https://www.inkgmr.net/kwrds.html

Keywords: gst, climate, storm, cyclone, vortex, noise, tipping, noise-induced tipping



martedì 18 luglio 2023

# gst: evolution of survivors compared to discrete vs continuous noise


<< Environmental variations can significantly influence how populations compete for resources, and hence shape their evolution. Here, (AA) study population dynamics subject to a fluctuating environment modeled by a varying carrying capacity changing continuously in time according to either binary random switches, or by being driven by a noise of continuous range. >>

<< the slow strain fixation probability can be greatly enhanced for a continuously varying environment compared to binary switches, even when the first two moments of the carrying capacity coincide. >>️

Ami Taitelbaum, Robert West, et al. Evolutionary dynamics in a varying environment: Continuous versus discrete noise. Phys. Rev. Research 5, L022004. April 4, 2023. 


Keywords: gst, evolution, noise, discrete vs continuous noise


sabato 4 maggio 2024

# gst: sudden noise-induced expansions beyond the onset of a steady symmetry-breaking bifurcation.

AA << consider fluid flows (..) subject to a steady symmetry-breaking bifurcation and forced by a weak noise acting on a slow timescale. >>

The validity of their proposed model << is tested on the flow past a sudden expansion for a given Reynolds number and different noise amplitudes. At a very low numerical cost, the statistics obtained from the amplitude equation accurately reproduce those of long-time direct numerical simulations. >>

Yves-Marie Ducimetière, Edouard Boujo, François Gallaire. Noise-induced transitions past the onset of a steady symmetry-breaking bifurcation: The case of the sudden expansion. Phys. Rev. Fluids 9, 053905. May 3, 2024. 

Also: transition, noise, in  https://www.inkgmr.net/kwrds.html 

Keywords: gst, transition, noise



mercoledì 2 agosto 2017

# s-gst: the importance of noise (transcriptional noise) in stem cell. dev., by Wolf et al.

<< Random differences between cells early in development could be the key to making different cells in the body, according to new research from a team co-led by Professor Wolf Reik >>

<< when cells start specialising into different cell types their gene activity becomes more 'noisy' - each cell starts to turn different groups of genes on or off >>

Noise helps cells make decisions: Team reveals the importance of genetic noise in development. Aug 1, 2017

https://m.phys.org/news/2017-08-noise-cells-decisions-team-reveals.html

AA << study systematically charts transcriptional noise and uncovers molecular processes associated with early lineage decisions >>

Hisham Mohammed, Irene Hernando-Herraez, et al. Single-Cell Landscape of Transcriptional Heterogeneity and Cell Fate Decisions during Mouse Early Gastrulation. Cell Reports , Volume 20 , Issue 5 , 1215 - 1228 doi: 10.1016/j.celrep.2017.07.009 Publ. Aug 1, 2017

http://www.cell.com/cell-reports/fulltext/S2211-1247(17)30961-0

mercoledì 8 maggio 2024

# gst: a case of noise-induced excitation wave (in coupled FH-N eq.)

<< There are various research topics such as stochastic resonance, coherent resonance, and neuroavalanche in excitable systems under external noises. >>️

AA << have studied the propagation of excitation waves in the coupled noisy FitzHugh-Nagumo equations with a one-dimensional pacemaker region and found that there is a phase-transition-like phenomenon from the short-range propagation to the whole-system propagation by changing the noise strength T.  >>️

Hidetsugu Sakaguchi. Noise-induced excitation wave and its size distribution in coupled FitzHugh-Nagumo equations on a square lattice. Phys. Rev. E 109, 044211. Apr 19, 2024.

Also: waves, noise, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, waves, noise, transition