23 papers · ranked by Valyu relevance
Maude Bouchard, Jean-Marc Lina, Pierre-Olivier Gaudreault, Alexandre Lafrenière + 3 more
Sleep slow waves are studied for their role in brain plasticity, homeostatic regulation and their changes during aging. Here, we address the possibility that two types of slow waves co-exist in humans. Thirty young and 29 older adults underwent a night of polysomnographic recordings. Using the Transition frequency…
Miguel Navarrete, Alejandro Osorio-Forero, Angela Gómez, David Henao + 2 more
Closed loop acoustic stimulation (CLAS) during sleep has shown to boost slow wave (SW) amplitude and spindle power. Moreover, sleep SW are suggested to be classified based on different processes of neuronal synchronization. Following this, different types of SW events may have distinct functional roles and be…
Ruchella Kock, David Hof, Reto Huber, Arko Ghosh
Real-world behavior unfolds as a continuous flow of actions over time. One possibility is that this continuous flow is enabled by a seamless stream of cortical activity. However, emerging evidence suggests that even during ongoing behaviors, cortical neural populations undergo brief periods of silence. This ‘off-state’…
Giulia Alessandrelli, Stephanie Huwiler, Giulio Bernardi, Manuel Carro-Domínguez + 13 more
The interplay between slow-wave sleep and cardiovascular health is increasingly recognized. Our prior research showed that auditory-enhanced slow waves can boost cardiac function, yet the mechanisms behind this remain unclear. Advancing these findings, our current analysis dissected the effects of two slow wave types…
Ruchella Kock, David Hof, Reto Huber, Arko Ghosh
Real-world behavior unfolds as a continuous flow of actions over time. One possibility is that this continuous flow is enabled by a seamless stream of cortical activity. However, emerging evidence suggests that even during ongoing behaviors, cortical neural populations undergo brief periods of silence. This ‘off-state’…
Chia-Chu Chiang, Xile Wei, Arvind Keshav Ananthakrishnan, Rajat S. Shivacharan + 3 more
'Rajat S. Shivacharan' 'Luis E. Gonzalez-Reyes' 'Mingming Zhang' 'Dominique M. Durand'] Fast and slow neural waves have been observed to propagate in the human brain during seizures. Yet the nature of these waves is difficult to study in a surgical setting. Here, we report an observation of two different traveling…
Marc P. Buckley, Jochen Horstmann, Ivan Savelyev, Jeff R. Carpenter
A large portion of the kinetic energy found within the ocean originates from the growth of ocean surface waves under the action of wind. However our understanding of wind wave dynamical coupling mechanisms remains incomplete. Competing theories exist but direct observational evidence is lacking, due to the technical…
Mathias Peuvrier, Laura Fernandez, Sylvain Crochet, Alain Destexhe + 1 more
Although classically Rapid-Eye Movement (REM) sleep is thought to generate desynchronized activity similar to wakefulness, it was found that some brain regions can express Slow Wave activity (SWA), a pattern which is normally typical of slow-wave sleep. To investigate possible underlying mechanisms, we analyze…
Xavier Barthélémy, Michael L. Banner, William L. Peirson, Frédéric Dias + 1 more
'Frédéric Dias' 'Michael J. Allis'] The kinematic properties of unsteady highly non-linear 3D wave groups have been investigated using a numerical wave tank. Although carrier wave speeds based on zero-crossing analysis remain within ±7% of linear theory predictions, crests and troughs locally undertake a systematic…
Francesco Fedele, Michael L. Banner, Xavier Barthélémy
Intuitively, crest speeds of water waves are assumed to match their phase speeds. However, this is generally not the case for natural waves within unsteady wave groups. This motivates our study, which presents new insights into the generic behavior of crest speeds of linear to highly nonlinear unsteady waves. While our…
Chiara Pilloton, Claudio Lugni, Giorgio Graziani, Francesco Fedele
We study channel turbulence by interpreting its vorticity as a random sea of ocean wave packet analogues. In particular, we investigate the ocean-like properties of vortical packets applying stochastic methods developed for oceanic fields. Taylor’s hypothesis of frozen eddies does not hold when turbulence is not weak…
Fedele, Francesco
We present a dynamical-systems perspective on wave breaking for ideal incompressible free-surface flows. By tracking the most energetic hotspot on the wave surface, we find that near breaking the surface slope evolves on a fast timescale governed by the small parameter = () −1 , the inverse vertical velocity gradient…
Michael L. Banner, Xavier Barthélémy, Francesco Fedele, Michael J. Allis + 3 more
'Michael J. Allis' 'Alvise Benetazzo' 'Frédéric Dias' 'William L. Peirson'] Observations show that maximally-steep breaking water wave crest speeds are much slower than expected. We report a wave-crest slowdown mechanism generic to unsteady propagating deep water wave groups. Our fully nonlinear computations show that…
Fabrizio Logiurato
Google Earth is a huge source of interesting illustrations of various natural phenomena. It can represent a valuable tool for science education, not only for teaching geography and geology, but also physics. Here we suggest that Google Earth can be used for introducing in an attractive way the physics of waves.
Mark L. McAllister, Nick Pizzo, Samuel Draycott, Ton S. van den Bremer
'Ton S. van den Bremer'] Deep-water surface wave breaking affects the transfer of mass, momentum, energy and heat between the air and sea. Understanding when and how the onset of wave breaking will occur remains a challenge. The mechanisms that form steep waves, i.e. nonlinearity or dispersion, are thought to have a…
Justin Eilertsen, Wylie Stroberg, Santiago Schnell
The determination of a substrate or enzyme activity by coupling of one enzymatic reaction with another easily detectable (indicator) reaction is a common practice in the biochemical sciences. Usually, the kinetics of enzyme reactions is simplified with singular perturbation analysis to derive rate or time course…
Authors not listed
Atomistic simulations provide essential mechanistic insights into chemical processes, yet many important phenomena in chemistry and materials science occur on timescales that are inaccessible to molecular dynamics. Existing computational approaches force a choice between atomic resolution on relatively short timescales…
Robert K. Niven, Jean-Noël Jaubert
The aim of this study is to explore the insights of the information-theoretic definition of similarity for a multitude of flow systems with wave propagation. This provides dimensionless groups of the form $(Π_{info}=U/c)$, where U is a characteristic flow velocity and c is a signal velocity or wave celerity, to…
Gabriel Birzu, Oskar Hallatschek, Kirill S. Korolev
Traveling waves describe diverse natural phenomena from crystal growth in physics to range expansions in biology. Two classes of waves exist with very different properties: pulled and pushed. Pulled waves are driven by high growth rates at the expansion edge, where the number of organisms is small and fluctuations are…
Authors not listed
Elucidating Collective Variables (CVs) for biomolecular dynamics is crucial for understanding numerous biological processes. By leveraging the tensor-train data structure, a multilinear version of the AMUSE (Algorithm for Multiple Unknown Signals) algorithm for Koopman approximation (AMUSEt) was recently developed to…
Pablo Baudin, Roethlisberger Ursula
A multiple time step (MTS) algorithm for trajectory surface hopping molecular dynamics has been developed, implemented, and tested. The MTS scheme is an extension of the ab initio implementation for Born{Oppenheimer molecular dynamics presented in [J. Chem. Theory Comput. 14, 2834 (2018)]. In particular, the MTS…
M. L. McAllister, S. Draycott, R. Calvert, T. Davey + 2 more
'T. S. van den Bremer'] Although a ubiquitous natural phenomenon, the onset and subsequent process of surface wave breaking are not fully understood. Breaking affects how steep waves become and drives air-sea exchanges1. Most seminal and state-of-the-art research on breaking is underpinned by the assumption of…
Yan Li, Amin Chabchoub
Wave transformation is an intrinsic dynamic process in coastal areas. An essential part of this process is the variation of water depth, which plays a dominant role in the propagation features of water waves, including a change in wave amplitude during shoaling and de-shoaling, breaking, celerity variation, refraction…