Bibliographies thématiques / Behavioral oscillations

Littérature scientifique sur le sujet « Behavioral oscillations »

Auteur : Grafiati
Publié le 10 mars 2023

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Articles de revues sur le sujet "Behavioral oscillations"

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Inagaki, Natsuko, Sato Honma, Daisuke Ono, Yusuke Tanahashi et Ken-ichi Honma. « Separate oscillating cell groups in mouse suprachiasmatic nucleus couple photoperiodically to the onset and end of daily activity ». Proceedings of the National Academy of Sciences 104, no 18 (26 avril 2007) : 7664–69. http://dx.doi.org/10.1073/pnas.0607713104.

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The pattern of circadian behavioral rhythms is photoperiod-dependent, highlighted by the conservation of a phase relation between the behavioral rhythm and photoperiod. A model of two separate, but mutually coupled, circadian oscillators has been proposed to explain photoperiodic responses of behavioral rhythm in nocturnal rodents: an evening oscillator, which drives the activity onset and entrains to dusk, and a morning oscillator, which drives the end of activity and entrains to dawn. Continuous measurement of circadian rhythms in clock gene Per1 expression by a bioluminescence reporter enabled us to identify the separate oscillating cell groups in the mouse suprachiasmatic nucleus (SCN), which composed circadian oscillations of different phases and responded to photoperiods differentially. The circadian oscillation in the posterior SCN was phase-locked to the end of activity under three photoperiods examined. On the other hand, the oscillation in the anterior SCN was phase-locked to the onset of activity but showed a bimodal pattern under a long photoperiod [light–dark cycle (LD)18:6]. The bimodality in the anterior SCN reflected two circadian oscillatory cell groups of early and late phases. The anterior oscillation was unimodal under intermediate (LD12:12) and short (LD6:18) photoperiods, which was always phase-lagged behind the posterior oscillation when the late phase in LD18:6 was taken. The phase difference was largest in LD18:6 and smallest in LD6:18. These findings indicate that three oscillating cell groups in the SCN constitute regionally specific circadian oscillations, and at least two of them are involved in photoperiodic response of behavioral rhythm.
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Knyazev, G. G. « Behavioral inhibition, behavioral activation, and brain oscillations ». International Journal of Psychophysiology 69, no 3 (septembre 2008) : 158–59. http://dx.doi.org/10.1016/j.ijpsycho.2008.05.403.

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ZHANG, Xiaodan, Lijin ZHANG, Yulong DING et Zhe QU. « Behavioral oscillations in attentional processing ». Advances in Psychological Science 29, no 3 (2021) : 460. http://dx.doi.org/10.3724/sp.j.1042.2021.00460.

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Erlikhman, Gennady, et Gideon Caplovitz. « Behavioral Oscillations in Shape Perception ». Journal of Vision 17, no 10 (31 août 2017) : 1382. http://dx.doi.org/10.1167/17.10.1382.

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Sihn, Duho, et Sung-Phil Kim. « Differential modulation of behavior by infraslow activities of different brain regions ». PeerJ 10 (1 février 2022) : e12875. http://dx.doi.org/10.7717/peerj.12875.

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The oscillation phase of electroencephalograms (EEGs) is associated with behavioral performance. Several studies have demonstrated this association for relatively fast oscillations (>1 Hz); a similar finding has also been reported for slower oscillations, showing that behavioral performance is correlated with the phase of infraslow activity (ISA, 0.01–0.1 Hz) of electroencephalography (EEG). However, the previous study only investigated ISA in a local brain region using a relatively simple task (somatosensory discrimination task), leaving it difficult to determine how the EEG ISA for various brain regions is associated with behavioral performance. In addition, it is not known whether the EEG ISA phase modulates more complex behavioral task performance. In the present study, we analyzed the ISA of whole-brain EEG of participants performing various behaviors while playing video games. We found that behavior was associated with the specific oscillation phase of EEG ISA when that behavior was independent of other behaviors. In addition, we found that the EEG ISA oscillation phases modulating the different behaviors varied across brain regions. Our results suggest that the EEG ISA for different brain regions modulates behavioral performance in different ways and such modulation of EEG ISA can be generalized to diverse behaviors. This study may deepen the understanding of how EEG ISA modulates behavior and increases the applicability of EEG ISA.
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Cole, Scott, et Bradley Voytek. « Cycle-by-cycle analysis of neural oscillations ». Journal of Neurophysiology 122, no 2 (1 août 2019) : 849–61. http://dx.doi.org/10.1152/jn.00273.2019.

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Neural oscillations are widely studied using methods based on the Fourier transform, which models data as sums of sinusoids. This has successfully uncovered numerous links between oscillations and cognition or disease. However, neural data are nonsinusoidal, and these nonsinusoidal features are increasingly linked to a variety of behavioral and cognitive states, pathophysiology, and underlying neuronal circuit properties. We present a new analysis framework, one that is complementary to existing Fourier and Hilbert transform-based approaches, that quantifies oscillatory features in the time domain on a cycle-by-cycle basis. We have released this cycle-by-cycle analysis suite as “bycycle,” a fully documented, open-source Python package with detailed tutorials and troubleshooting cases. This approach performs tests to assess whether an oscillation is present at any given moment and, if so, quantifies each oscillatory cycle by its amplitude, period, and waveform symmetry, the latter of which is missed with the use of conventional approaches. In a series of simulated event-related studies, we show how conventional Fourier and Hilbert transform approaches can conflate event-related changes in oscillation burst duration as increased oscillatory amplitude and as a change in the oscillation frequency, even though those features were unchanged in simulation. Our approach avoids these errors. Furthermore, we validate this approach in simulation and against experimental recordings of patients with Parkinson’s disease, who are known to have nonsinusoidal beta (12–30 Hz) oscillations. NEW & NOTEWORTHY We introduce a fully documented, open-source Python package, bycycle, for analyzing neural oscillations on a cycle-by-cycle basis. This approach is complementary to traditional Fourier and Hilbert transform-based approaches but avoids specific pitfalls. First, bycycle confirms an oscillation is present, to avoid analyzing aperiodic, nonoscillatory data as oscillations. Next, it quantifies nonsinusoidal aspects of oscillations, increasingly linked to neural circuit physiology, behavioral states, and diseases. This approach is tested against simulated and real data.
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Manor, Yair, John Rinzel, Idan Segev et Yosef Yarom. « Low-Amplitude Oscillations in the Inferior Olive : A Model Based on Electrical Coupling of Neurons With Heterogeneous Channel Densities ». Journal of Neurophysiology 77, no 5 (1 mai 1997) : 2736–52. http://dx.doi.org/10.1152/jn.1997.77.5.2736.

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Manor, Yair, John Rinzel, Idan Segev, and Yosef Yarom. Low-amplitude oscillations in the inferior olive: a model based on electrical coupling of neurons with heterogeneous channel densities. J. Neurophysiol. 77: 2736–2752, 1997. The mechanism underlying subthreshold oscillations in inferior olivary cells is not known. To study this question, we developed a single-compartment, two-variable, Hodgkin-Huxley-like model for inferior olive neurons. The model consists of a leakage current and a low-threshold calcium current, whose kinetics were experimentally measured in slices. Depending on the maximal calcium and leak conductances, we found that a neuron model's response to current injection could be of four qualitatively different types: always stable, spontaneously oscillating, oscillating with injection of current, and bistable with injection of current. By the use of phase plane techniques, numerical integration, and bifurcation analysis, we subdivided the two-parameter space of channel densities into four regions corresponding to these behavioral types. We further developed, with the use of such techniques, an empirical rule of thumb that characterizes whether two cells when coupled electrically can generate sustained, synchronized oscillations like those observed in inferior olivary cells in slices, of low amplitude (0.1–10 mV) in the frequency range 4–10 Hz. We found that it is not necessary for either cell to be a spontaneous oscillator to obtain a sustained oscillation. On the other hand, two spontaneous oscillators always form an oscillating network when electrically coupled with any arbitrary coupling conductance. In the case of an oscillating pair of electrically coupled nonidentical cells, the coupling current varies periodically and is nonzero even for very large coupling values. The coupling current acts as an equalizing current to reconcile the differences between the two cells' ionic currents. It transiently depolarizes one cell and/or hyperpolarizes the other cell to obtain the regenerative response(s) required for the synchronized oscillation. We suggest that the subthreshold oscillations observed in the inferior olive can emerge from the electrical coupling between neurons with different channel densities, even if the inferior olive nucleus contains no or just a small proportion of spontaneously oscillating neurons.
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Kim, Bowon, Bernat Kocsis, Eunjin Hwang, Youngsoo Kim, Robert E. Strecker, Robert W. McCarley et Jee Hyun Choi. « Differential modulation of global and local neural oscillations in REM sleep by homeostatic sleep regulation ». Proceedings of the National Academy of Sciences 114, no 9 (13 février 2017) : E1727—E1736. http://dx.doi.org/10.1073/pnas.1615230114.

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Homeostatic rebound in rapid eye movement (REM) sleep normally occurs after acute sleep deprivation, but REM sleep rebound settles on a persistently elevated level despite continued accumulation of REM sleep debt during chronic sleep restriction (CSR). Using high-density EEG in mice, we studied how this pattern of global regulation is implemented in cortical regions with different functions and network architectures. We found that across all areas, slow oscillations repeated the behavioral pattern of persistent enhancement during CSR, whereas high-frequency oscillations showed progressive increases. This pattern followed a common rule despite marked topographic differences. The findings suggest that REM sleep slow oscillations may translate top-down homeostatic control to widely separated brain regions whereas fast oscillations synchronizing local neuronal ensembles escape this global command. These patterns of EEG oscillation changes are interpreted to reconcile two prevailing theories of the function of sleep, synaptic homeostasis and sleep dependent memory consolidation.
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Ghazanfar, Asif A., et Donald B. Katz. « Distributed neural substrates and the evolution of speech production ». Behavioral and Brain Sciences 21, no 4 (août 1998) : 516–17. http://dx.doi.org/10.1017/s0140525x9828126x.

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There is evidence of reciprocal connectivity, similarity of oscillatory responses to stimulation of multiple motor and somatosensory cortices, whole system oscillation, and short- latency responses to behavioral perturbation. These suggest that frame/content may be instantiated by overlapping neural populations, and that the genesis of frame oscillations may be profitably thought of as an emergent property of a distributed neural system.
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Liu, Ling, et Huan Luo. « Behavioral oscillation in global/local processing : Global alpha oscillations mediate global precedence effect ». Journal of Vision 19, no 5 (17 mai 2019) : 12. http://dx.doi.org/10.1167/19.5.12.

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Thèses sur le sujet "Behavioral oscillations"

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Chen, Danjue. « Studies of traffic oscillations : a behavioral perspective ». Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48975.

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Traffic oscillations, or simply stop-and-go waves, are a common phenomenon arising in congested traffic but still not well understood. This phenomenon causes broad adverse impacts to safety risk, fuel efficiency and greenhouse emission. To eliminate or reduce those impacts, understanding the cause and propagation mechanism is essential. This dissertation studied driving behavior in traffic oscillations with the objective to uncover the formation and propagation mechanism of traffic oscillations. This study establishes a behavioral car-following model, the Asymmetric Behavioral model, based on empirical trajectory data that is able to reproduce the spontaneous formation and ensuing propagation of traffic oscillations in congested traffic. By analyzing individual drivers' car-following behavior throughout oscillation cycles it is found that this behavior is consistent across drivers and can be captured by a simple model. The statistical analysis of the model's parameters reveals that driver' behavior during oscillation (i.e., reaction to oscillation) is strongly correlated with driver behavior before oscillations and it varies with the development stage of the oscillation. Simulation of the model shows that it is able to produce characteristics of traffic oscillations consistently with empirical observations. This study also unveils the generation mechanism of the traffic hysteresis phenomenon arising in traffic oscillations using the Asymmetric Behavioral model. It is found that the occurrence of traffic hysteresis is closely correlated with driver behavior when experiencing traffic oscillations. In the growth and fully-developed stage of traffic oscillations, drivers behave differently, which results in different distribution of hysteresis patterns. This research makes it possible to unveil new management and control strategies of traffic oscillations to improve traffic operation and to quantify the environmental and safety impacts of traffic oscillations. For example, it can be used to estimate the increase of greenhouse emission and decrease of fuel efficiency imposed by traffic oscillations. It can also be used to study the increase of accident rate.
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Siegle, Joshua H. (Joshua Hangman). « Causal evidence for the behavioral impact of oscillations in neocortex and hippocampus ». Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/95857.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Neuroscientists hold widely divergent opinions on the behavioral relevance of oscillatory brain states. Some consider them to be a side effect of anatomical connectivity, with little or no role in guiding action. Others view them as a fundamental feature of the network states that underlie perception and cognition. In this thesis, I take a systematic approach to studying two of the most prominent types of oscillations,'gamma rhythms in the neocortex (30-80 Hz) and theta rhythms in the hippocampus (4-12 Hz). In both cases, I use light-gated ion channels to manipulate spike activity on a cycle-by-cycle basis in awake, behaving mice. By rhythmically stimulating fast-spiking interneurons in somatosensory cortex, I can emulate the activity patterns that define gamma oscillations under natural conditions. Emulating gamma enhances the detection of threshold-level vibrissae deflections, analogous to the behavioral effects of shifting attention. By triggering stimulation of fast-spiking interneurons in the hippocampus on peaks and troughs of endogenous rhythms, I can reduce spike activity at specific phases of theta. In the context of a spatial navigation task, I find that the ability of inhibition to enhance decision-making accuracy depends on both the theta phase and the task segment in which it occurs. Both of these experiments provide novel causal evidence for the behavioral impact of oscillations, which offers a much more compelling argument for their utility than traditional correlative measures. Finally, I present a new platform for extracellular electrophysiology. This platform, called Open Ephys, makes the closed-loop experiments that are ideal for studying oscillations accessible to a wider audience.
by Joshua H. Siegle.
Ph. D.
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Cicchese, Joseph John. « Theta Oscillations Modulate Hippocampal Single-Unit Responses Across Subregions During Trace Eyeblink Classical Conditioning ». Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1466187297.

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Hadzibegovic, Senka. « Behavioral, molecular and electrophysiological characterization of the learning and memory deficits induced in mouse models of Alzheimer’s disease ». Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0151/document.

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La maladie d’Alzheimer (MA) se caractérise par une perte des fonctions cognitives liée à une dégénérescence neuronale induite par l’accumulation de peptides amyloïdes-β (Aβs) dans des régions vulnérables du cerveau comme l’hippocampe. Au niveau moléculaire, les peptides Aβs se lient préférentiellement à la densité post-synaptique des synapses excitatrices, espace au niveau duquel la protéine d’échafaudage PSD-95 organise l’ancrage des récepteurs NMDA (RNMDAs) et régule leur mobilité membranaire. A l’aide d’une stratégie intégrative qui favorise des niveaux d’analyse verticaux (du phénotype aux événements moléculaires) et qui combine un ensemble d’approches corrélatives et invasives chez des souris double transgéniques APPswe/PS1dE9 modèles de la MA, nous avons mis en évidence que les peptides Aβs déstabilisent l’organisation synaptique (altération de l’expression de la PSD-95) et augmentent le pool extrasynaptique de sous-unités GluN2B des RNMDAs dans l’hippocampe. Cette réorganisation se traduit par une perturbation des fonctions mnésiques. Par ailleurs, il a été montré que certaines oscillations de l’activité hippocampique, comme les « sharp-wave ripples » (SWRs) générées pendant les périodes de sommeil, jouent un rôle crucial dans la formation de la mémoire. De façon surprenante, l’accumulation des peptides Aβs semble épargner la dynamique d’expression des SWRs durant les comportements de routine. Afin d’examiner l’effet potentiel des Aβs sur les SWRs chez des animaux confrontés à des challenges cognitifs, nous avons soumis des souris adultes injectées intracérébralement avec une solution d’Aβs à un test de reconnaissance spatiale. Alors qu’elles sont capables de former une mémoire à court terme, les souris Aβs montrent un oubli plus rapide, suggérant qu’elles encodent avec succès, mais qu’elles sont incapables de stabiliser et de rappeler une information acquise antérieurement. En l’absence d’une demande cognitive préalable, les propriétés des SWRs ne sont pas altérées par les Aβs. En revanche, lorsqu’elles doivent résoudre un test cognitif, les pics de SWRs normalement observés après encodage ou reconnaissance chez les souris témoins sont abolis chez les souris Aβs, indiquant une perturbation du traitement hippocampique de l’information spatiale. Pris dans leur ensemble, ces résultats identifient deux nouveaux mécanismes délétères sous-tendant les déficits de mémoire spatiale associés à la MA
Cognitive impairments in Alzheimer’s disease (AD) are thought to be related to degenerative synaptic changes caused by the accumulation of amyloid-β peptides (Aβs) in vulnerable brain regions such as the hippocampus. At the molecular level, Aβs bind preferentially to the postsynaptic density of neuronal excitatory synapses, where the scaffolding post-synaptic protein-95 (PSD-95) organizes NMDA receptor (NMDAR) location as well as its downstream signaling. By using an integrative strategy which favoured vertical levels of analyses (from phenotype to molecular events) and combined a set of interrelated correlative and invasive approaches in a double transgenic mouse model of AD (APPswe/PS1dE9 mice), we were successful in establishing that Aβs destabilize the synaptic organization (reduction of expression of PSD-95) and increase the extrasynaptic pool of GluN2B-containing NMDAR in the hippocampus, a reorganization which translates into impaired memory functions. It is also well-known that hippocampal sharp wave-ripples (SWRs) generated during sleep periods are crucial for memory formation but accumulation of soluble Aβs, surprisingly seems to spare SWR dynamics during routine behavior. To unravel a potential effect of Aβs on SWRs in cognitively-challenged animals, we submitted vehicle- and Aβ-injected mice to spatial recognition memory testing. While capable of forming short-term memory, Aβ mice exhibited faster forgetting, suggesting successful encoding but an inability to adequately stabilize and/or retrieve previously acquired information. Without prior cognitive requirements, similar properties of SWRs were observed in both groups. In contrast, when cognitively challenged, the post-encoding and -recognition peaks in SWR occurrence observed in controls were abolished in Aβ mice, indicating impaired hippocampal processing of spatial information. Altogether these results identify two new disruptive mechanisms for the spatial memory deficits associated with AD
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Rabiller, Gratianne. « Contribution of hippocampal diaschisis to the memory deficits associated with focal cerebral ischemia in the rat : converging behavioral, electrophysiological and functional evidence ». Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0461/document.

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Les mécanismes impliqués dans les troubles cognitifs induits à la suite d’une ischémie cérébrale (IC) demeurent mal compris. En plus du cœur ischémique nécrosé et de la zone de pénombre entourant cette lésion, certaines régions éloignées de la zone ischémique peuvent être fonctionnellement affectées, un phénomène connu sous le nom de «diaschisis». Sachant qu’il existe de fortes interactions fonctionnelles entre l’hippocampe (HPC) et le cortex lors des processus mnésiques, nous avons émis la possibilité que les troubles mnésiques survenant après une IC focale qui préserve l’intégrité de l’HPC, auraient pour origine une perturbation de la connectivité cortico-hippocampique conduisant à un hypofonctionnement hippocampique induit par le phénomène de diaschisis. Afin d’éprouver cette hypothèse, nous avons utilisé le modèle d’occlusion permanente de l'artère cérébrale moyenne chez le rat (OPACM) qui reproduit l’ischémie cérébrale focale humaine. Dans ce modèle, le cortex somato-sensoriel (SS) est endommagé unilatéralement alors que l’intégrité de l’HPC est préservé. Les rats OPACM ont montré une diminution de l’expression du gène c-fos dans l’HPC lors de l'exploration d'un nouvel environnement, indiquant une hypoactivation neuronale. Les rats OPACM ont également présenté une perturbation des mémoires olfactive associative et spatiale lors des tests de transmission sociale de préférence alimentaire (TSPA) et du Barnes maze, respectivement. Afin de confirmer que l’hypofonctionnement hippocampique induit par l’IC résultait d’une réduction des afférences corticales («déactivation») provenant du cortex endommagé, nous avons réalisé des inactivations pharmacologiques spécifiques du cortex SS et ou de l’HPC par injection de lidocaïne ou de CNQX. Ces injections ont induit une hypoactivation hippocampique (réduction du nombre de noyaux Fos-positifs) associée à une perturbation mnésique dans le test de TSPA. L'activité hippocampique chez des rats anesthésiés pendant l’IC ou deux semaines après, ainsi que lors de l’inactivation pharmacologique du cortex SS, a également été examinée par une approche électrophysiologique. Les résultats ont montré une altération de la fréquence d’apparition des «sharp-wave ripples» hippocampiques et révélé une instabilité de la fréquence thêta hippocampique lors de la reperfusion ou deux semaines après IC, ainsi que lors de l’inactivation corticale, suggérant une altération de la dynamique d’interaction entre l’HPC et le cortex. Pris dans leur ensemble, ces résultats identifient le phénomène de diaschisis hippocampique comme un mécanisme crucial impliqué dans l’hypofonctionnement hippocampique et les déficits mnésiques observés après une IC
The cognitive consequences and the underlying mechanisms leading to cognitive impairments after cerebrovascular occlusive diseases are still unclear. In addition to the infarct zone that suffer the deadly consequence of ischemic stroke, the penumbra surrounding the lesion site and some brain regions more remote to the ischemic areas can be functionally affected by the insult. This phenomenon is referred to as diaschisis. In light of the importance of interactions between hippocampus and cortex during memory processing, we hypothesized that the cognitive impairments observed following focal ischemia could occur in the absence of direct hippocampal insult, possibly via impaired connectivity within cortico-hippocampal networks leading to diaschisis-induced hypofunctioning in specific hippocampal subregions. To examine this possibility, we used the distal middle cerebral artery occlusion (dMCAO) ischemic model in rats which induces restricted cortical infarct in the somatosensory (SS) cortex in the absence of direct hippocampal injury. dMCAO rats exhibited reduced expression of the activity-dependent gene c-fos in the hippocampus when exploring a novel environment, indicating neuronal hypoactivation. Ischemic rats also showed impaired associative olfactory and spatial memory when tested in the social transmission of food preference (STFP) task and the Barnes maze test, respectively. To confirm that the ischemic-induced hippocampal hypofunctioning resulted from reduced afferent inputs (i.e. deactivation) originating in the damaged cortex, we performed region-specific pharmacological inactivation of SS and/or HPC using lidocaine or CNQX. Fos imaging revealed that these treatments induced hippocampal hypoactivation and impaired memory performance as measured in the STFP task. We additionally performed electrophysiological recordings of hippocampal activity in anesthetized rats during acute stroke and two weeks later or after SS cortex inactivation. We found an alteration in the occurrence of sharp-wave ripples associated with instability of theta frequency during reperfusion after stroke and SS cortex inactivation, suggesting an alteration in the dynamics of hippocampal-cortical interactions. Taken collectively, these findings identify hippocampal diaschisis as a crucial mechanism for mediating stroke-induced hippocampal hypofunction and associated memory deficits
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Aravamuthan, Bhooma Rajagopalan. « Comparing the radiological anatomy, electrophysiology, and behavioral roles of the pedunculopontine and subthalamic nuclei in the normal and parkinsonian brain ». Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:9a735b39-c1fe-4d5f-b05f-3385f27e6e58.

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Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and DBS of the pedunculopontine nucleus (PPN) have been shown to be effective surgical therapies for Parkinson’s disease (PD). To better understand the PPN and STN as DBS targets for PD, this research compares the anatomy, electrophysiology, and motor control roles of these nuclei. PPN and STN connections were examined in vivo in human subjects and in the non-human primate using probabilistic diffusion tractography. Both the PPN and STN were connected with each other and with the motor cortex (M1) and basal ganglia. After studying these anatomical connections in primates, their functional significance was further explored in an anesthetized rat model of PD. Examination of the electrophysiological relationship between the PPN and basal ganglia in the presence of slow cortical oscillatory activity suggested that excitatory input from the STN may normally modulate PPN spike timing but that inhibitory oscillatory input from the basal ganglia output nuclei has a greater effect on PPN spike timing in the parkinsonian brain. To examine transmission and modulation of oscillatory activity between these structures at higher frequencies, LFP activity was recorded from the PPN and STN in PD patients performing simple voluntary movements. Movement-related modulation of oscillatory activity predominantly occurred in the α (8-12 Hz) and low β (12-20 Hz) frequencies in the STN but in the high β (20-35 Hz) frequencies in the PPN, supporting observations from rodent studies suggesting that oscillatory activity is not directly transmitted from the STN to the PPN in PD. Finally, to better understand the roles of the STN and PPN in large-scale movement, the effects of STN and PPN DBS on gait abnormalities in PD patients were studied. DBS of the STN appeared to improve gait by optimising executive gait control while DBS of the PPN appeared to restore autonomic gait control. These results have several implications for DBS patient selection, surgical targeting, and for understanding the mechanisms underlying DBS efficacy.
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Schumann, Michael. « Nonlinear dynamics in oscillating waterfalls ». PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4421.

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Zhang, Huihui. « Temporal dependence in perceptual decision-making : behavioural oscillations and sequential effects ». Thesis, The University of Sydney, 2019. http://hdl.handle.net/2123/20847.

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Dynamic brain states influence perceptual decision making, especially when the immediate sensory evidence is noisy. In this thesis, I examine how perceptual decision making is shaped by two types of temporal contexts, one characterised by intrinsic temporal organisation of neural processing (i.e., neural oscillations) and one characterised by the recent history of perceptual, decisional, and motor experience (i.e., sequential effects). Chapter 2 examines rhythmic fluctuations of behavioural performance in visual orientation discrimination. The results indicate that sensitivity and response bias both modulate rhythmically over time: ~8 Hz for sensitivity, and ~10 Hz for response bias. Chapter 3 examines sequential effects in visual orientation discrimination. Analysing the data-set from chapter 2 shows that it’s the response, rather than the stimulus, that carries over to the next trial. Moreover, the one-trial back sequential effect shows individual differences (positive or negative). In a new experiment with a trial-by-trial random stimulus-response mapping, the choice effect was consistently positive and the motor effect was consistently repulsive, suggesting that the individual differences may be caused by different relative weightings of the perceptual decision and the motor response. Chapter 4 further examines sequential effects with auditory stimuli of different morph levels in two dimensions: gender, syllable (ba/da). Observers reported male or female and ba or da at the same time. For gender, decisions were biased towards the previous choice, and this bias was modulated by the similarity between previous and current stimuli – being stronger when the stimuli were similar. For syllable, the same bias towards previous choice was found, but the dependence was not modulated by similarity between temporally adjacent stimuli. To summarise, these findings reveal that both intrinsic neural oscillations and past history shape the current perceptual decision making.
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Iachello, Marco. « Nonlinear oscillations in high power systems ». Doctoral thesis, Università di Catania, 2015. http://hdl.handle.net/10761/3913.

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The main topic of this work is to investigate on nonlinear phenomena affecting high power systems and on the strategies adopted to model them. In the first chapter the attention is focused on two big areas of high power systems: power electronics and systems/devices used to sustain plasma fusion. Although it is common that System Engineers tend to associate high power systems with power electronics, it is worth noting that power systems related to nuclear fusion represent a challenging area rich in nonlinearities. Specifically, while nonlinear oscillations in power electronics are due to oscillations of electrical nature, the ones present in nuclear fusion can also refer to other physical quantities. We will refer to the latter taking into account macroscopic plasma instabilities affecting JET plasmas, and proposing both theoretical approaches and experimental ones to describe their dynamic. The former rely on nonlinear mathematical equations able to mimic the nonlinear behavior of the system under certain conditions while the latter are based on a physical realization of the system starting from its mathematical model. High power systems related to power electronics are investigated in Chapter 2 where the importance of thermal modeling for the power electronics modules is pointed out and a new modeling strategy which starts from a distributed parameter analysis to obtain a lumped parameter model is introduced. In this case, the proposed methodology is based on the assumption that the heat transfer problem can be assumed to be linear and the thermal impedances approaches can be therefore used. In this relevant case study nonlinearities in modeling high power systems can also be neglected under certain conditions. In particular, concerning high power modules, it is well-known how the geometry of the device and the proper choice of the cooling system can play a key role for these simplifications. A data-driven approach based on neural networks to model plasma instabilities is presented in Chapter 3. This approach is introduced because physical models often require a deep knowledge of the system parameters that sometimes is difficult to obtain. In Chapter 4 considerations and results on new identification methodologies based on parallel identification models for discrete-time systems are presented.
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Feingold, Joseph. « Beta oscillations in frontal cortex and striatum represent post-processing of successful behavior ». Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68453.

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Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Beta band (13-30 Hz) oscillations in sensorimotor cortex are associated with motor performance, but the nature of this relationship is not clear. Recently, excessive beta activity in cortico-basal ganglia circuits has been recognized as a hallmark of Parkinson's disease. Renewed interest in beta oscillations has since led to the suggestion that they might reflect the preservation of the current output or state of a given brain region. To investigate the potential role of beta activity in the brain, we recorded local field potentials in the frontal cortex and striatum of monkeys as they performed single and sequential arm movement tasks. To facilitate these experiments, we developed novel methods for recording simultaneously from independently moveable electrodes implanted chronically at over 100 sites in cortical and subcortical areas of the monkey brain. We found that, across tasks, beta oscillations occurred in brief, spatially localized bursts that were most prominent following task performance. Across brain regions, post-performance bursts were differentially modulated by the preceding task. In motor cortex they tracked the number of movements just performed. In contrast, striatal and prefrontal burst rates were proportional to the number of visual cues, or to a combination of the cues and movements, respectively, and were higher following correct, rewarded, trials than unrewarded errors. Pairs of striatal-prefrontal sites exhibited increased cross-covariance and coherence during post-trial beta bursts, suggesting that these bursts might be involved in communication or coordination across brain regions. Based on our results, we propose that beta oscillations may represent post-performance reinforcement of the network dynamics that led to the desired behavioral outcome obtained immediately prior.
by Joseph Feingold.
Ph.D.
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Livres sur le sujet "Behavioral oscillations"

1

McRuer, D. T. Pilot-induced oscillations and human dynamic behavior. [Washington, D. C.] : National Aeronautics and Space Administration, Office of Management, Scientific and Technical Program, 1995.

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McRuer, Duane T. Pilot-induced oscillations and human dynamic behavior. Edwards, Calif : Dryden Flight Research Center, 1995.

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Chaotic oscillations in mechanical systems. Manchester : Manchester University Press, 1991.

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I, Neĭmark I͡U. Stochastic and chaotic oscillations. Dordrecht : Kluwer Academic Publishers, 1992.

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Yu, Pogromsky A., dir. Introduction to control of oscillations and chaos. Singapore : World Scientific, 1998.

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Oscillations, waves, and chaos in chemical kinetics. Oxford : Oxford University Press, 1994.

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I, Neĭmark I͡U. Stokhasticheskie i khaoticheskie kolebanii͡a. Moskva : "Nauka," Glav. red. fiziko-matematicheskoĭ lit-ry, 1988.

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Gaponov-Grekhov, A. V. Nonlinearities in action : Oscillations, chaos, order, fractals. Berlin : Springer-Verlag, 1992.

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Seminar on Oscillation, Bifurcation, and Chaos (1986 University of Toronto). Oscillation, bifurcation, and chaos : Proceedings of the 1986 annual seminar held July 13-25, 1986. Sous la direction de Atkinson F. V, Langford W. F, Mingarelli Angelo B. 1952-, Canadian Mathematical Society et Natural Sciences and Engineering Research Council Canada. Providence, R.I : Published by the American Mathematical Society for the Canadian Mathematical Society, 1987.

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Anishchenko, V. S. Dynamical chaos in physical systems : Experimental investigation of self-oscillating circuits. Leipzig : BSB B.G. Teubner Verlagsgesellschaft, 1989.

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Chapitres de livres sur le sujet "Behavioral oscillations"

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Nishida, Hiroshi, Muneyoshi Takahashi, A. David Redish et Johan Lauwereyns. « High Frequency Oscillations for Behavioral Stabilization During Spatial Alternation ». Dans Advances in Cognitive Neurodynamics (IV), 531–35. Dordrecht : Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-9548-7_76.

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Bergman, Hagai, Thomas Wichmann, Benny Karmon et Mahlon R. DeLong. « Parkinsonian Tremor is Associated with Low Frequency Neuronal Oscillations in Selective Loops of the Basal Ganglia ». Dans Advances in Behavioral Biology, 317–25. Boston, MA : Springer US, 1994. http://dx.doi.org/10.1007/978-1-4613-0485-2_33.

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Colella, Cristianna. « Endogenous Oscillations ». Dans Encyclopedia of Animal Cognition and Behavior, 2337–38. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-319-55065-7_1920.

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Colella, Cristianna. « Endogenous Oscillations ». Dans Encyclopedia of Animal Cognition and Behavior, 1–3. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-47829-6_1920-1.

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Wu, Jianhong, et Xue Zhang. « Oscillations Due To Diapause ». Dans Transmission Dynamics of Tick-Borne Diseases with Co-Feeding, Developmental and Behavioural Diapause, 103–36. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-54024-1_6.

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Szemplińska-Stupnicka, Wanda. « Normal Oscillations in Autonomous Conservative Systems ». Dans The Behavior of Nonlinear Vibrating Systems, 1–43. Dordrecht : Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-1870-2_1.

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Szemplińska-Stupnicka, Wanda. « Free Oscillations with Arbitrary Initial Conditions ». Dans The Behavior of Nonlinear Vibrating Systems, 70–86. Dordrecht : Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-1870-2_3.

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Inoue, Katsumi, et Chiaki Sakama. « Oscillating Behavior of Logic Programs ». Dans Correct Reasoning, 345–62. Berlin, Heidelberg : Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-30743-0_23.

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Szemplińska-Stupnicka, Wanda. « Normal Oscillations of Elastic Nonlinear Continuous Systems ». Dans The Behavior of Nonlinear Vibrating Systems, 44–69. Dordrecht : Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-1870-2_2.

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Stein, Robert F., et Mats Carlsson. « Dynamic Behavior of the Solar Atmosphere ». Dans SCORe ’96 : Solar Convection and Oscillations and their Relationship, 261–76. Dordrecht : Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5167-2_27.

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Actes de conférences sur le sujet "Behavioral oscillations"

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Saracini, Chiara. « Bistable Perception’s Oscillations Dynamics, Individual Differences and Cognitive Flexibility : A Behavioral Study ». Dans IECBS 2022. Basel Switzerland : MDPI, 2022. http://dx.doi.org/10.3390/iecbs2022-13742.

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Goncalves, Hernani, Diogo Ayres-de-Campos et Joao Bernardes. « The effect of gender, gestational age and behavioral states on fetal heart rate variability ». Dans 2014 8th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO). IEEE, 2014. http://dx.doi.org/10.1109/esgco.2014.6847498.

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Nardelli, Mimma, Gaetano Valenza, Ioana A. Cristea, Claudio Gentili, Carmen Cotet, Daniel David, Antonio Lanata et Enzo P. Scilingo. « Characterization of behavioral activation in non-pathological subjects through Heart Rate Variability monovariate and multivariate multiscale entropy analysis ». Dans 2014 8th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO). IEEE, 2014. http://dx.doi.org/10.1109/esgco.2014.6847556.

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Padilla, Rodrigo, Vibhav Durgesh et Tao Xing. « Application of Proper Orthogonal Decomposition to Study the Flow Over an Oscillating Flag ». Dans ASME 2022 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/fedsm2022-86969.

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Abstract Fluid-Structure-Interaction (FSI) is the coupling between a flowing fluid and a structure that results in either a static or dynamic structure deformation. This investigation focused on applying Proper Orthogonal Decomposition (POD) to study the fluid flow behavior of an oscillating flag and using POD modes to quantify the changes in flow behavior associated with the change in flag oscillation modes. For this purpose, aerodynamic load, membrane location, and Particle Image Velocimetry (PIV) measurements were performed for a selected flag model. The flag location measurements helped identify the change in oscillation shapes and modes with change in flow conditions, while the aerodynamic load data allowed us to quantify the impact of flag oscillations on the aerodynamic load experienced by the flag. The PIV data provide flow field information around the oscillating flag and were used to perform POD analysis. We observed that the POD mode, energy, and time-varying coefficients changed with change in the oscillation modes of the flag (i.e., change from mode-2 to mode-3 oscillations). Flow reconstruction using the first three POD modes allowed us to capture changes generated in large-scale structures in the flow due to changes in the oscillation modes. Flow reconstruction using the remaining POD modes allowed us to observe the behavior of small-scale flow structures and K-H vortices in the wake of the flag. The POD approach used here allowed us to quantify the change in flow behavior and understand the underlying FSI mechanism therein.
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Tamura, Tetsuro, Akira Hayakawa et Ray Okada. « Numerical Study on Aeroelastic Behavior of a Circular Cylinder With Two Degrees of Freedom ». Dans ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0062.

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Abstract When a circular cylinder is transversely set in fluid flows, various kinds of oscillations in the in-line as well as the cross-flow direction occur due to the aerodynamic forces, which are mainly induced by periodic vortex sheadings. In case of large amplitude, an oscillating cylinder interacts with flows close to the cylinder surface and generates the distinct vortex shedding patterns. We numerically simulate the aeroelastic behaviors of a circular cylinder. Namely, a cylinder is elastically mounted for both in-line (x) and cross-flow (y) directions, therefore can translationally oscillate in any direction in uniform flows. We examine the aeroelastic characteristics in the in-line and the cross-flow vortex-induced oscillations, and relations among different types of modal motions of a circular cylinder with two degrees of freedom. It is shown that, with regard to the response characteristics, computational results based on three-dimensional simulations agree with the experimental results. In order to clarify the mechanism of the vortex-induced oscillation, we also investigate flow structures under oscillation, for example, the behaviors of separated layers from the cylinder and their following process of vortex formation in the near wake.
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Richards, George A., et Michael C. Janus. « Characterization of Oscillations During Premix Gas Turbine Combustion ». Dans ASME 1997 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-gt-244.

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The use of premix combustion in stationary gas turbines can produce very low levels of NOx emissions. This benefit is widely recognized, but turbine developers routinely encounter problems with combustion oscillations during the testing of new pre mix combustors. Because of the associated pressure fluctuations, combustion oscillations must be eliminated in a final combustor design. Eliminating these oscillations is often time-consuming and costly because there is no single approach to solve an oscillation problem. Previous investigations of combustion stability have focused on rocket applications, industrial furnaces, and some aeroengine gas turbines. Comparatively little published data is available for premised combustion at conditions typical of an industrial gas turbine. In this paper, we report experimental observations of oscillations produced by a fuel nozzle typical of industrial gas turbines. Tests are conducted in a specially designed combustor, capable of providing the acoustic feedback needed to study oscillations. Tests results are presented for pressures up to 10 atmospheres, and with inlet air temperatures to 588 K (600 F) burning natural gas fuel. Based on theoretical considerations, it is expected that oscillations can be characterized by a nozzle reference velocity, with operating pressure playing a smaller role. This expectation is compared to observed data, showing both the benefits and limitations of characterizing the combustor oscillating behavior in terms of a reference velocity rather than other engine operating parameters. This approach to characterizing oscillations is then used to evaluate how geometric changes to the fuel nozzle will affect the boundary between stable and oscillating combustion.
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Tamura, Tetsuro, et Yoshiaki Itoh. « Numerical Study on Aeroelastic Instability of a Rectangular Cylinder in Heaving Oscillations ». Dans ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0061.

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Abstract The unsteady three-dimensional flows around a forced-oscillating or freely oscillating rectangular cylinder are numerically simulated by means of the direct finite difference method without any turbulence model. We discuss the accuracy of the present method for prediction of unsteady aerodynamic forces and responses to various dynamic properties. First we examine the aerodynamic forces in case of forced oscillation with D/B = 2 of a rectangular cylinder through the comparison with experiments. Also, in order to understand fundamental behaviors of unstable oscillations of a rectangular cylinder, which is elastically mounted in heaving mode in uniform flow, the effect of various dynamic parameters such as mass ratio, damping ratio or the Scruton number, on aeroelastic instabilities is individually investigated.
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Moon, Jong Hoon, Byung Ha Kang et Ho-Young Kim. « Effects of Acoustic Resonance on Hydrodynamics and Evaporation of a Pendant Liquid Droplet ». Dans ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems collocated with the ASME 2005 Heat Transfer Summer Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ipack2005-73111.

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One of the fascinating prospects is the possibility of new hydrodynamics technology on micro-scale system since oscillations of micro-droplets are of practical and scientific importance. In this paper, nonlinear and forced oscillations of supported viscous droplet were focused. The droplet has a free contact line with solid plate and inviscid fluid. Natural frequencies of a pendant droplet have been investigated experimentally by imposing the acoustic wave while the frequency is being increased at fixed amplitude. The evaporation process of oscillating droplet with thermofoil has been also observed to investigate analyzing the resonance effect on the thermal characteristics of droplet. It is found that a pendant droplet shows the resonant behaviors at each mode similar to the theoretical analysis. During imposing the acoustic wave, the pendant droplet makes a rotating motion in its longitudinal axis which is a new shape oscillation mode. The evaporation rate of a pendant droplet at resonant frequency is significantly enhanced.
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Zhan, Dexin, Don Spencer et David Molyneux. « Numerical Analysis of FPSO Behavior in Ocean Towing ». Dans ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41964.

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This paper presents numerical analysis of the behavior of a towed FPSO using an in-house computer code Ship Maneuvering Laboratory (SML). The background of the study was an attempt to explain some unexpected observations during a towing situation, where the position of the towed vessel was on the upwind side of the towing vessel and oscillating in yaw. The effects of rudder, wind and current were investigated initially. Then the study focused on the behavior of the towed FPSO with different hydrodynamic coefficients in an environment of steady wind varying from 1.0 to 25 knots with the wind direction on the starboard bow of the tug. The tug was assumed to move in a straight line at a constant speed. It was found that with the calculated MMG coefficients the FPSO had large oscillations of track and yaw when the wind speed was low (1 knot). When the wind speed was increased, the FPSO moved to the starboard side of the tug (up wind) and kept oscillating and yawing but with less amplitude. This was similar to the FPSO behavior observed in the incident. This phenomenon of oscillating and yawing of the FPSO was not seen when using the measured PMM hydrodynamic coefficients. One possible explanation for the FPSO behavior in the incident was related to the specific values of the FPSO’s hydrodynamic coefficients. Some possible methods to reduce the FPSO yaw oscillation are also provided. Numerical results showed that by adding drag created by a drogue to the FPSO or using a longer towing bridle can significantly increase the directional stability of the FPSO. A sensitivity study of the FPSO hydrodynamic coefficients is also given and some conclusions are provided.
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Urban, Brigitte, Heinz Stetter et Nicolas Vortmeyer. « Experimental Investigation of Shock-Induced Blade Oscillation at an Elastically Suspended Turbine Cascade in Transonic Flow ». Dans ASME Turbo Expo 2000 : Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0378.

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Experimental investigations on shock-induced flutter in a linear transonic turbine cascade are presented. To examine the relation between trailing edge shock oscillations on adjacent blades in transonic flow and observed turbine blade vibrations, an elastic suspension system has been developed so that only aerodynamic coupling occurs in the system. The experimental investigations have been performed on a linear test rig with superheated steam as working fluid. The test facility enables Mach and Reynolds numbers to be varied independently. The investigated cascade consists of seven blades which are taken from the tip section of a transonic low pressure steam turbine blade. Each blade is attached by an elastic spring system which allows the respective blade to vibrate in a mode equal to the real blade’s first bending mode. By varying the individual spring stiffness it is possible to either get a tuned or mistuned cascade. The examinations mainly deal with the oscillatory behavior of the blades with respect to a variation in the isentropic outlet Mach number. In addition, the complex shock-boundary-layer interaction on the blades’ suction sides is described. An important result is that the maximum blade oscillation amplitude can be related to a specific outlet Mach number. At this Mach number all seven blades are vibrating with exactly the same frequency. This phenomenon is observed at both the tuned and the mistuned cascades. Spectrum analysis shows that one of the major shock oscillation frequencies corresponds to the flutter frequency. In addition to this frequency the spectrum analysis of the blade oscillation shows the dominant frequencies of the shock oscillation which are not natural blade frequencies. The experimental results show that oscillating shocks in a linear cascade give high potential for aeroelastic excitation of transonic blades under certain flow conditions. Blade oscillations and shock characteristics are discussed in detail.
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