Article
Physics, Multidisciplinary
Claudio Maggi, Nicoletta Gnan, Matteo Paoluzzi, Emanuela Zaccarelli, Andrea Crisanti
Summary: This paper studies an active particles system near the motility-induced critical point and demonstrates that a nonequilibrium coloured noise field can capture the coarse-grained behavior of the system. The study shows that active particles violate the equilibrium fluctuation-dissipation in the high-wave-vector and high-frequency regime, but the critical dynamics is effectively in equilibrium at larger spatiotemporal scales. A field-theoretical description using a space-time correlated noise field qualitatively captures the numerical results.
COMMUNICATIONS PHYSICS
(2022)
Article
Neurosciences
Chia-Hsi Jessica Lin, Dolores Bozovic
Summary: The efferent pathway enhances the auditory system by fine-tuning the response and protecting the inner ear from noise-induced damage. The specific mechanisms of its otoprotective role and its impact on hair cell recovery are still not fully understood. This study explored the effects of efferent stimulation on the recovery of hair cells and found that it can change the recovery profile and eliminate the transition to quiescence.
Article
Physics, Multidisciplinary
Edgar Roldan, Jeremie Barral, Pascal Martin, Juan M. R. Parrondo, Frank Juelicher
Summary: This study introduces lower bounds for the rate of entropy production of an active stochastic process by quantifying the irreversibility of stochastic traces obtained from mesoscopic degrees of freedom. The analysis reveals irreversibility in active oscillations and estimates an associated rate of entropy production. Experimental recordings suggest that measuring both the tip position of the hair bundle and the mechano-electrical transduction current can provide tighter lower bounds for the rate of entropy production.
NEW JOURNAL OF PHYSICS
(2021)
Article
Chemistry, Physical
Alireza Shakerpoor, Elijah Flenner, Grzegorz Szamel
Summary: Researchers derived a distribution function for the position of a tagged active particle in a system of interacting active particles, revealing a new effective temperature that is determined by the ratio of self-diffusion and tagged particle mobility coefficients.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Neurosciences
Alexandra L. Scharr, Daibhid O. Maoileidigh, Anthony J. Ricci
Summary: The hair bundle, composed of mechanically coupled stereocilia, is a universal mechanosensory organelle in auditory, vestibular, and lateral-line systems. The dynamics of individual stereocilia in response to bundle stimulus has not been quantified. By stimulating and tracking individual inner-hair-cell stereocilia, it was found that nonuniform stimulation led to dissimilar stereociliary displacements and stereocilia closer to the stimulator moved more. The weak coupling between stereocilia suggests that more uniform stimulation across the tallest stereocilia is required to enhance the receptor current.
JOURNAL OF NEUROSCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Cheng Cheng, Yilin Hou, Zhonghong Zhang, Yanfei Wang, Ling Lu, Liyan Zhang, Pei Jiang, Song Gao, Qiaojun Fang, Chengwen Zhu, Junyan Gao, Xufeng Liu, Wei Xie, Zhengping Jia, Zhigang Xu, Xia Gao, Renjie Chai
Summary: This study demonstrates the crucial role of the autism-related gene Pak1 in hearing function using Pak1 knockout mice. PAK1 deficiency leads to hair cell apoptosis and severe hearing loss, suggesting Pak1 as a potential target for clinical diagnosis of autism-related hearing loss.
JOURNAL OF GENETICS AND GENOMICS
(2021)
Article
Physics, Mathematical
Denis Bernard, Tony Jin
Summary: The research presents a solution for the invariant probability measure of the one-dimensional Q-SSEP model by constructing steady correlation functions of the system density matrix and quantum expectation values. These correlation functions contain rich structures of fluctuating quantum correlations and coherences, based on an interplay between permutation groups and polynomials rather than standard techniques from the theory of integrable systems. Additionally, a possible combinatorial interpretation of the Q-SSEP correlation functions is pointed out through a surprising connection with geometric combinatorics and associahedron polytopes.
COMMUNICATIONS IN MATHEMATICAL PHYSICS
(2021)
Article
Astronomy & Astrophysics
Kostas Glampedakis, George Pappas
Summary: The unprecedented image of the M87* supermassive black hole has sparked controversy over its usefulness as a test of the general relativistic Kerr metric. The paper argues that our ability to probe gravity with a black hole shadow is only partially impaired by the matter degrees of freedom and the number of non-Kerr parameters used in the model. Existing limits from gravitational wave observations imply that supermassive systems like the M87* black hole would suffer a suppression of all non-GR deviation parameters in their metric.
Article
Physics, Fluids & Plasmas
Domingos S. P. Salazar
Summary: Fluctuation theorems set fundamental limits on the statistics of entropy production, with the information quantification and upper bound determined by the maximal distribution. This bound is verified in various scenarios, including heat transfer and qubit swap engines, showcasing the versatility of the theory.
Article
Physics, Fluids & Plasmas
Ricardo Gutierrez, Carlos Perez-Espigares
Summary: The study of dynamical large deviations reveals a dynamical phase transition in two-dimensional random walk models, with insights provided by both numerical microscopic characterization and macroscopic fluctuation theory. The spectral analysis of the microscopic generator shows that this continuous phase transition involves spontaneous symmetry breaking, leading to the loss of reflection symmetry in the stationary solution. Such dynamical phase transitions, which do not depend on exclusion effects or interactions, may be observed in more complex nonequilibrium physics models.
Article
Physics, Particles & Fields
Ke Wang
Summary: In this paper, a new method is used to retest the no-hair theorem of black holes in the framework of general relativity. The behavior of black holes is probed using the data from GW150914, and the results support the predictions of general relativity.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Biophysics
Sajad Abolpour Moshizi, Christopher John Pastras, Rajni Sharma, M. A. Parvez Mahmud, Rachel Ryan, Amir Razmjou, Mohsen Asadnia
Summary: Balance disorders are a common problem that affects approximately 30% of the population. Various treatment methods, including the vestibular prosthesis, stem cell regeneration, and gene therapies, are being explored. Artificial hair cell sensors show great promise as a new technology.
BIOSENSORS & BIOELECTRONICS
(2022)
Article
Multidisciplinary Sciences
Andrew A. Mecca, Giusy A. Caprara, Anthony W. Peng
Summary: This study found that up-regulation of cAMP lowers the sensitivity of the channel by decreasing the stiffness of the gating spring. Prolonged depolarization can also mimic the effects of cAMP. The results suggest that cAMP signaling modulates gating spring stiffness to affect auditory sensitivity.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Physics, Fluids & Plasmas
Julian Kappler, Ronojoy Adhikari
Summary: This paper presents a method for measuring irreversibility in stochastic processes experimentally. By considering the probability ratio of trajectories remaining in the tubular neighborhood of a smooth path and its time reversal, the pathwise medium entropy production is obtained and can be derived from measurable tube probabilities. Estimation of the latter from numerically sampled trajectories shows excellent agreement with theory. By combining our measurement of pathwise entropy production with a Markov chain Monte Carlo algorithm, the entropy-production distribution for a transition path ensemble can be inferred directly from short recorded trajectories.
Article
Audiology & Speech-Language Pathology
Patricia M. Quinones, Sebastiaan W. F. Meenderink, Brian E. Applegate, John S. Oghalai
Summary: The study found that unloaded OHC bundles do not spontaneously oscillate in the mouse cochlea, which is different from observations in non-mammalian ears.
Article
Biophysics
Jeremie Barral, Frank Juelicher, Pascal Martin
BIOPHYSICAL JOURNAL
(2018)
Article
Biology
Melanie Tobin, Atitheb Chaiyasitdhi, Vincent Michel, Nicolas Michalski, Pascal Martin
Article
Multidisciplinary Sciences
Mathieu Richard, Carles Blanch-Mercader, Hajer Ennomani, Wenxiang Cao, Enrique M. De La Cruz, Jean-Francois Joanny, Frank Juelicher, Laurent Blanchoin, Pascal Martin
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2019)
Article
Multidisciplinary Sciences
Jeremie Barral, Xiao-Ding Wang, Alex D. Reyes
NATURE COMMUNICATIONS
(2019)
Article
Physics, Multidisciplinary
Luis Dinis, Juan Manuel Rodriguez Parrondo
Summary: This paper demonstrates the reversible confinement of a Brownian particle in an optical tweezer potential, allowing for optimal work extraction despite high measurement inaccuracy.
Article
Multidisciplinary Sciences
R. G. Alonso, M. Tobin, P. Martin, A. J. Hudspeth
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Microbiology
Josue Jara, Francisco Alarcon, Ajay K. Monnappa, Jose Ignacio Santos, Valentino Bianco, Pin Nie, Massimo Pica Ciamarra, Angeles Canales, Luis Dinis, Ivan Lopez-Montero, Chantal Valeriani, Belen Orgaz
Summary: Under hydrodynamic stress, bacteria can adapt by increasing cell density and matrix production in biofilms. This adaptation leads to the formation of mechanically stable biofilms with a higher number of crosslinks and enriched carbohydrate compositions in the matrix, affecting both structure and viscoelastic properties.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Multidisciplinary Sciences
Alberto Molina-Cardin, Luis Dinis, Maria Luisa Osete
Summary: The model presented in this study is able to replicate the periodic reversals and excursions of the geomagnetic field by explaining the random perturbations affecting two coupled particles in potential energy. The temporal asymmetry of geomagnetic reversals is attributed to the model's out-of-equilibrium state, with a thermal imbalance between the two particles.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Physics, Condensed Matter
Pascal Martin, A. J. Hudspeth
Summary: Recognition of sounds involves analyzing frequency content, evoking mechanical waves traveling within the cochlea to specific places, detection by hair cells and hair bundles, and enhancement of sensitivity and frequency tuning through active processes. Operation near a Hopf bifurcation provides nonlinear generic features characteristic of hearing, and multiple gradients tune hair cells to cover our auditory range.
ANNUAL REVIEW OF CONDENSED MATTER PHYSICS, VOL 12, 2021
(2021)
Article
Physics, Multidisciplinary
Edgar Roldan, Jeremie Barral, Pascal Martin, Juan M. R. Parrondo, Frank Juelicher
Summary: This study introduces lower bounds for the rate of entropy production of an active stochastic process by quantifying the irreversibility of stochastic traces obtained from mesoscopic degrees of freedom. The analysis reveals irreversibility in active oscillations and estimates an associated rate of entropy production. Experimental recordings suggest that measuring both the tip position of the hair bundle and the mechano-electrical transduction current can provide tighter lower bounds for the rate of entropy production.
NEW JOURNAL OF PHYSICS
(2021)
Article
Neurosciences
Nadege Marin, Fernando Lobo Cerna, Jeremie Barral
Summary: The vertebrate ear has remarkable perceptual capabilities and can detect faint sounds through efficient amplification. This amplification mechanism may involve somatic electromotility and active hair-bundle motility. In addition, the hearing system has exceptional frequency discrimination, allowing for accurate distinction of complex sounds. This is achieved through frequency decomposition in the cochlea. Tonotopy, the relation between activation frequency and cochlear location, plays a major role in this decomposition.
MOLECULAR AND CELLULAR NEUROSCIENCE
(2022)
Article
Physics, Multidisciplinary
Marie Pochitaloff, Martin Miranda, Mathieu Richard, Atitheb Chaiyasitdhi, Yasuharu Takagi, Wenxiang Cao, Enrique M. De la Cruz, James R. Sellers, Jean-Francois Joanny, Frank Juelicher, Laurent Blanchoin, Pascal Martin
Summary: The authors demonstrate that the wave-like motion of cilia can be reconstituted in vitro by self-assembling polymerizing actin filaments and myosin motors. The binding of myosin to actin depends on the shape of the actin bundle, providing a feedback mechanism for the coordination between motor activity and filament deformations.
Article
Mechanics
L. Dinis, J. Unterberger, D. Lacoste
Summary: Finding the optimal survival strategies of living systems in fluctuating environments involves balancing phenotypic diversification and sensing. This study focuses on two randomly switching phenotypes subjected to two stochastically switching environments, and explores the optimal asymptotic growth rate as well as finite time growth rate fluctuations. The results suggest a close connection between variance and extinction probability, and highlight the trade-off between average growth rate and variance in the model.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2022)
Article
Physics, Multidisciplinary
L. Dinis, J. Unterberger, D. Lacoste