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The control of the entrainment and diffusion of the heat and mass ejected along the jet flow requires the control of fluid motion. In the present study, optimal initial velocity distributions for suppressing and promoting jet entrainment and diffusion were identified using deep reinforcement learning under constant initial jet flow rate conditions. Two-dimensional jet flow simulations using OpenFOAM were combined with a deep Q-network as the learning algorithm. The spatial distribution of the initial jet (velocity and ejection angle) changed. The results show that to suppress the entrainment of the jet, an optimal initial velocity distribution shape in which the velocity in the centre is almost 0, with an inward velocity just outside of it, and a large outward velocity at the outer edge, is desirable. However, to promote entrainment, a shape with a large velocity in the centre portion and small velocity at the outer edge, with an overall inward angle, is desirable. To suppress the diffusion of the jet, an optimal initial velocity distribution shape with a large velocity in the centre portion, a small velocity at the outer edge, and an overall inward angle is desirable. Conversely, to promote diffusion, a shape with a large outward velocity at both the centre and outer edges is desirable. It is also indicated that, when the initial velocity distribution of the jet has a special shape, and the relationship between flow rate, centre velocity, and centre temperature that is normally observed in a jet flow may not hold. In other words, by changing the initial velocity distribution, the entrainment and diffusion of the jet can be separated and controlled, which is usually difficult to achieve using conventional engineering methods., Version of Record 12 October 2023

It is well understood that almost all organisms exhibit daily oscillations in behavior and physiology. These circadian rhythms are capable of being entrained to environmental stimuli, such as light. The circadian system is sensitive to a broad spectrum of light, but mice specifically lack long wavelength sensitive photopigments. I therefore hypothesized that blue-enriched lighting would be better at entraining the circadian system of wild-type (WT) mice compared to red-enriched lighting. My results suggest that under stable phase conditions, the spectral composition of light is of little consequence; however, in response to changes in phase, the spectral properties of light do matter.

Body temperature in homeothermic animals does not remain constant but displays a regular circadian fluctuation within a physiological range (e.g., 35°C–38.5°C in mice), constituting a fundamental systemic signal to harmonize circadian clock-regulated physiology. Here, we find the minimal upstream open reading frame (uORF) encoded by the 5′ UTR of the mammalian core clock gene Per2 and reveal its role as a regulatory module for temperature-dependent circadian clock entrainment. A temperature shift within the physiological range does not affect transcription but instead increases translation of Per2 through its minimal uORF. Genetic ablation of the Per2 minimal uORF and inhibition of phosphoinositide-3-kinase, lying upstream of temperature-dependent Per2 protein synthesis, perturb the entrainment of cells to simulated body temperature cycles. At the organismal level, Per2 minimal uORF mutant skin shows delayed wound healing, indicating that uORF-mediated Per2 modulation is crucial for optimal tissue homeostasis. Combined with transcriptional regulation, Per2 minimal uORF-mediated translation may enhance the fitness of circadian physiology.

An experiment is made of entrainment in two-layer or three-layer stratified fluids in a rotating system, where turbulence for mixing is produced by an oscillating grid in the upper layer. Flow visualization by dye, aluminium powder, and shadow graphs reveals peculiar characteristics of turbulence in rotating stratiaied fluids : strong spike-like turbulence above the interface and weak thin filaments elongated downward just beneath the interface. It is found that rotation causes even the downward entrainment, which is never observed in non-rotating stratified fluids.

The synchronization of words in conversation, called entrainment, is generally observed in human-human conversations. Entrainment has a high correlation with dialogue success, naturalness, and engagement. In this article, we de ne entrainment scores based on the word similarities in semantic space to evaluate the entrainment of system generation.We optimized a neural conversation model to the entrainment scores using reinforcement learning so that the system can control the degree of entrainment of the system response. Experimental results showed that the proposed entrainable neural conversation model generated comparable or more natural responses than conventional models and satisfactorily controlled the degree of entrainment of the generated responses.

We investigate bifurcations of periodic solutions observed in the forced Wilson-Cowan neuron pair by both the brute-force computation and the shooting method. By superimposing the results given by both methods, a detailed topological classification of periodic solutions is achieved that includes tori and chaos attractors in the parameter space is achieved. We thoroughly explore the parameter space composed of threshold values, amplitude, and angular velocity of an external forcing term. Many bifurcation curves that are invisible when using brute-force method are solved by the shooting method. We find out a typical bifurcation structure including Arnold tongue in the angular velocity and the amplitude of the external force parameter plane, and confirm its fractal structure. In addition, the emergence of periodic bursting responses depending on these patterns is explained.

Rhythmicity is a key component that allows humans to attend to, predict, and respond to the environment. In particular, temporal processing is fundamental to the perception and production of complex sounds, such as speech and music. Neural entrainment hypothesizes that internal oscillators synchronize with external stimuli, providing a unified mechanism for supramodal temporal processing. Extensive research demonstrates the entrainment effect on human time perception for non-speech musical sounds; fewer studies have shown entrainment effects for duration perception in spoken language. To date, it remains unclear how humans encode temporal properties and generate rhythm according to them, and whether and how entrainment mechanisms represent timing information in the brain. My aim is to address these important open questions. In Chapter 1 of my thesis, I reviewed the existing literature and gaps therein. Chapter 2 compared whether entrainment or interval models more accurately predict human time perception. Entrainment models more accurately predicted duration discrimination, but the effect diminished after 2-4 cycles, while interval models predicted more accurately thereafter. Chapter 3 tested entrainment effects on more ecologically valid contexts -- speech sounds, and found that entrainment can transfer from tones to speech sounds, suggesting a domain-general entrainment effect with a constraint by acoustical similarity. Chapter 4 examined neural evidence of entrainment in hierarchically organized drumming rhythm. The study found that both auditory and motor regions represent the rhythms imagined by the subjects. A motor-to-auditory information flow was found in all listening conditions without overt movements, suggesting that the motor system actively maintains hierarchical information and exerts a top-down influence on auditory processing and metrical imagery of rhythms. Chapter 5 further investigated rhythm production using self-paced tapping and synchronization

We define forward entrainment as that part of behavioral or neural entrainment that outlasts the entraining stimulus. In this review, we examine conditions under which one may optimally observe forward entrainment. In Part 1, we review and evaluate studies that have observed forward entrainment using a variety of psychophysical methods (detection, discrimination, and reaction times), different target stimuli (tones, noise, and gaps), different entraining sequences (sinusoidal, rectangular, or sawtooth waveforms), a variety of physiological measures (MEG, EEG, ECoG, CSD), in different modalities (auditory and visual), across modalities (audiovisual and auditory-motor), and in different species. In Part 2, we describe those experimental conditions that place constraints on the magnitude of forward entrainment, including an evaluation of the effects of signal uncertainty and attention, temporal envelope complexity, signal-to-noise ratio (SNR), rhythmic rate, prior experience, and intersubject variability. In Part 3 we theorize on potential mechanisms and propose that forward entrainment may instantiate a dynamic auditory afterimage that lasts a fraction of a second to minimize prediction error in signal processing.

Daytime atmospheric boundary layer (ABL) dynamics—including potential temperature budgets, water vapour budgets, and entrainment rates—are presented from in situ flight data taken on six afternoons near Fresno in the San Joaquin Valley (SJV) of California during July/August 2016. The flights took place as a part of the California Baseline Ozone Transport Study aimed at investigating transport pathways of air entering the Central Valley from offshore and mixing down to the surface. Midday entrainment velocity estimates ranged from 0.8 to 5.4 cm s−1 and were derived from a combination of continuously determined ABL heights during each flight and model-derived subsidence rates, which averaged -2.0 cm s−1 in the flight region. A strong correlation was found between entrainment velocity (normalized by the convective velocity scale) and an inverse bulk ABL Richardson number, suggesting that wind shear at the ABL top plays a significant role in driving entrainment. Similarly, we found a strong correlation between the entrainment efficiency (the ratio of entrainment to surface heat fluxes with an average of 0.23 ± 0.15) and the wind speed at the ABL top. We explore the synoptic conditions that generate higher winds near the ABL top and propose that warm anomalies in the southern Sierra Nevada mountains promote increased entrainment. Additionally, a method is outlined to estimate turbulence kinetic energy, convective velocity scale (w*), and the surface sensible heat flux in the ABL from a slow, airborne wind measurement system using mixed-layer similarity theory.

Neural entrainment is a phenomenon whereby neural oscillations adjust their frequency to synchronize with the periodic vibration of external stimuli. Research suggests that neural entrainment may help explain the relationship between music education and more optimal cognitive performance later in development. This dissertation tested whether sensory entrainment caused short-term cognitive and motor performance benefits in a young adult sample, and whether entrainment or performance were impacted by stimulus parameters like modality or rhythm or individual differences in attentional ability and music training. Participants (N= 47) were asked to report the extent and type (e.g. instrumental, vocal) of music experience and severity of ADHD symptoms, and then were exposed to repetitive 1.25-Hz or arrhythmic visual or auditory stimuli with interlaced Flanker test items, while EEG was recorded. At some points in the experiment participants were additionally tasked with tapping along to the 1.25-Hz beat through both beat stimuli and gaps. Some entrainment and performance effects were congruent with findings from prior literature, while many other hypotheses regarding entrainment effects were not supported. In terms of individual differences, neither music training nor ADHD symptoms impacted entrainment, but ADHD did impact the effects of entrainment stimuli on Flanker reaction time, with higher ADHD symptoms predicting worse performance during periods of rhythmic stimulation. Lastly and surprisingly, while neither entrainment, music training, nor ADHD symptoms impacted beat-keeping performance in general, ADHD symptoms predicted better beat-keeping during stimulus gap periods. Results in general paint a complicated picture of acute entrainment effects and individual differences.

During conversational interactions such as tutoring, instruction-giving tasks, verbal negotiations, or just talking with friends, interlocutors’ behaviors experience a series of changes due to the characteristics of their counterpart and to the interaction itself. These changes are pervasively present in every social interaction, and most of them occur in the sounds and rhythms of our speech, which is known as acoustic-prosodic accommodation, or simply phonetic accommodation. The consequences, linguistic and social constraints, and underlying cognitive mechanisms of phonetic accommodation have been studied for at least 50 years, due to the importance of the phenomenon to several disciplines such as linguistics, psychology, and sociology. Based on the analysis and synthesis of the existing empirical research literature, in this paper we present a structured and comprehensive review of the qualities, functions, onto- and phylogenetic development, and modalities of phonetic accommodation., Durante las interacciones conversacionales como dar una tutoría, dar instrucciones, las negociaciones verbales, o simplemente hablar con amigos, los comportamientos de las personas experimentan una serie de cambios debido a las características de su interlocutor y a la interacción en sí. Estos cambios están presentes en cada interacción social, y la mayoría de ellos ocurre en los sonidos y ritmos del habla, lo cual se conoce como acomodación acústico-prosódica, o simplemente acomodación fonética. Las consecuencias, las limitaciones lingüísticas y sociales, y los mecanismos cognitivos subyacentes a la acomodación fonética se han estudiado durante al menos 50 años, debido a la importancia del fenómeno para varias disciplinas como la lingüística, la psicología, y la sociología. A partir del análisis y síntesis de la literatura de investigación empírica existente, en este artículo presentamos una revisión estructurada y exhaustiva de las cualidades, funciones, desarrollo onto- y filogenético, y modalidades de la acomodación fonética.

This master thesis explores the potential of Rhythmic Entrainment (RE) for product design applications. The research starts by defining some of the important terms and providing example cases of RE from products and research. A comparison between the cases illuminates the possibilities RE can have for product design and research. [1] RE can create interesting new product interactions, [2] the theory is not applied as broadly across industries. The second part of this thesis aims to collect and present the knowledge that is relevant to start designing with RE. A framework inspired by embodied interactions is presented, categorizing between human-product-context. The framework approaches designing with RE in an iterative manner, fostering simplicity while acknowledging the complexity of the design process. A product Benchmark test showed that being “hands on” can help designers understand the design tensions. These tensions are caused by the temporality of rhythm, the interaction between factors of the system and the particularity of cases. Interviews with experts in rhythm (by job, hobby or ability) showed how it can evoke strong emotions and create engaging experiences. The latter occurs when the full system interacts with each other, creating a loop of continuous feedback on the human rhythm, provided by the context or product. In literature, these symmetrical interactions with rhythm are considered valuable, but the practical knowledge and applications are not available. Therefore the last part determines the factors that influence different levels of responsive interactions from research. To test wether a more responsive interaction is preferable, a research through design case is executed with a design problem from Glimp. It wants to adjust its breathing rhythm to the user and guide it towards the goal rhythm of the exercise. This case resulted in a concept that applies a “configuration” level of responsiveness, while taking skill and data, Integrated Product Design

Glacial debris flows with high mobility and long run-out distance have posed a growing threat to human life and critical infrastructure under climate change. The dynamics and mobility of glacial debris flows are related to many physical factors, among which initial ice/water content, phase transition, and entrainment might be the most important. A typical glacial debris flow occurred on 10 September 2020 near Namcha Barwa Peak in Tibet Plateau and travelled about 10 km under no precipitation condition. The major unsolved mechanical questions for the high mobility of this glacial debris flow include: What is the primary water source of this glacial debris flow? How do the water and ice affect the dynamics of the glacial debris flow? Which physical factor dominates the high mobility characteristics of the glacial debris flow? To answer these questions and deepen our understanding, we adopted the Pudasaini and Mergili (2019) advanced multi-phase mass flow model implemented in the computational tool (r.avaflow) to back-calculate this event. Through well-designed numerical experiments, we revealed that the initial water content is the major water source of this glacial debris flow event. We analyzed the impact of the initial ice/water fraction, phase transition, and entrainment on the mobility of the glacial debris flow. Results show that the initial ice/water content and entrainment are critical to the mobility of the glacial debris flow in the initial and later transport stage, respectively, while the phase transition only plays a minor role. Our study promotes mechanical understanding of the high mobility of this kind of glacial debris flow events. © 2023 Elsevier B.V.

Interpersonal synchronization is fundamental for motor coordination during social interactions. Discerning emergent (entrainment) from planned synchronization represents a non-trivial issue in visually bonded individuals acting together, as well as assessing whether inter-individual differences, e.g., in autistic traits, modulate both types of synchronization. In a visuomotor finger-tapping task, two participants replicated a target tempo either synchronizing (‘joint’ condition) or not (‘non-interactive’ condition, ‘non-int’) with each other. One participant was exposed (‘induced’) to tempo aftereffect (a medium tempo seems faster or slower after exposure to slower or faster inducing tempi), but not the other participant (‘not induced’); thus they had different timing perceptions of the same target. We assessed to what degree emergent and/or planned synchronization affected dyads by analyzing inter-tap-intervals, synchronization indexes, and cross-correlation coefficients. Results revealed a ‘tempo aftereffect contagion’: inter-tap-intervals of both induced and not-induced participants showed aftereffect in both the joint and non-int conditions. Moreover, aftereffects did not correlate across conditions suggesting they might be due to (at least in part) different processes, but the propensity for tempo aftereffect contagion correlated with individuals' autistic traits only in the non-int condition. Finally, participants co-adjusted their tapping more in the joint condition than in the non-int one, as confirmed by higher synchronization indexes and the mutual adaptation pattern of cross-correlation coefficients. Altogether, these results show the subtle interplay between emergent and planned interpersonal synchronization mechanisms that act on a millisecond timescale independently from synching or not with the partner.

Spontaneous motion synchrony between interaction partners benefits the interaction. Here we probed how musical rhythms, which are highly temporally organized, modulate this process. We video-taped conversations held in silence or with an auditory background that was metrical and regular (one measure looped), metrical and irregular (different measures in random order), non-metrical and regular, or non-metrical and irregular. Motion time-series derived from the videos entered a cross-wavelet coherence analysis showing that more musical rhythms amplified rhythm-relevant motion frequencies at the level of the individual and facilitated social synchronizing at the level of the dyad. Yet, we also observed rhythm-specific motion interference effects and reduced conversation pleasantness when compared with silence. These results indicate that musical rhythms, perhaps by imposing a temporally rigid mode of synchronizing, hinder rather than further ongoing social processes. Silence or sounds with little temporal organization and predictability seem preferable as a backdrop for interactional exchange. © The Author(s) 2021.

Debris flows can grow greatly in size and hazardous potential by eroding bed and bank materials. However, erosion mechanisms are poorly understood because debris flows are complex hybrids between a fluid flow and a moving mass of colliding particles, bed erodibility varies between events, and field measurements are hard to obtain. Here, we identify the key controls on debris-flow erosion based on a field data set that combines information on flow properties, bed conditions, and bed and bank erosion. We show that flow conditions and bed wetness jointly control debris-flow erosion. Flow conditions describing the cumulative forces exerted at the bed during an event best explain erosion. Shear forces and particle-impact forces are strongly correlated and act in conjunction in the erosion process. A shear-stress approach accounting for bed erodibility may therefore be applicable for modeling and predicting debris-flow erosion. This work provides a foundation for developing effective debris-flow erosion models.

Understanding erosion and entrainment of material by debris flows is essential for predicting and modelling debris-flow volume growth and hazard potential. Recent advances in field, laboratory and modelling studies have distilled two driving forces behind debris-flow erosion: impact and shear forces. How erosion and these forces depend on debris-flow composition and interact remains unclear. Here, we experimentally investigate the effects of debris-flow composition and volume on erosion processes in a small-scale flume with a loosely packed bed. We quantify the effects of gravel, clay and solid fraction in the debris flow on bed erosion. Erosion increased linearly with gravel fraction and volume, and decreased with increasing solid fraction. Erosion was maximal around a volumetric clay fraction of 0.075 (fraction of the total solid volume). Under varying gravel fractions and flow volumes erosion was positively related to both impact and shear forces, while these forces themselves are also correlated. Results further show that internal dynamics driving the debris flows, quantified by Bagnold and Savage numbers, correlate with erosional processes and quantity. Impact forces became increasingly important for bed erosion with increasing grain size. The experiments with varying clay and solid fractions showed that the abundance and viscosity of the interstitial fluid affect debris-flow dynamics, erosional mechanisms and erosion magnitude. High viscosity of the interstitial fluid inhibits the mobility of the debris flow, the movement of the individual grains and the transfer of momentum to the bed by impacts, and therefore inhibits erosion. High solid content possibly decreases the pore pressures in the debris flow and the transport capacity, inhibiting erosion, despite high shear stresses and impact forces. Our results show that bed erosion quantities and mechanisms may vary between debris flows with contrasting composition, and stress that entrainment models and volu

Humans have a flexible and accurate ability to coordinate their movement in time with external rhythms. However, it remains unclear when and how, during their development, human children acquire the ability to adjust tempo and control the timing of their movement toward others. A previous study suggested that such self-regulation of coordination develops at around 18 and 30 months after birth. In this study, we investigated the performance of 24-month-old children and compared their data with those of 18- and 30-month-olds provided in our previous study. In the joint-drumming task, each child was enticed to drum under four conditions [partner: mother or robot; speed: 400 or 600 ms inter-stimulus-interval (ISI)]. The most pivotal test condition was the 600 ms ISI speed condition (slower than children’s spontaneous motor tempo in these age groups). We found that from the age of 24 months, children try to slow down their drumming tempo toward the 600 ms ISI speed condition, regardless of the drumming partner. On the other hand, significant timing control toward the onset of the 600 ms ISI condition was observed from the age of 30 months. This implies that both motor and cognitive mechanisms are required for flexible tempo adjustment and accurate synchronization and that these develop gradually among 18-, 24-, and 30-month-olds.

Rhythmic motion in organisms is driven by central pattern generators (CPG). A CPG converts high-level input from the brain to low-level oscillatory input to the muscles via neuron spikes. Here a particular CPG, a reciprocal inhibition oscillator(RIO), is connected to an underdamped pendulum with position feedback to form a closed-loop system. Two types of neuron models are considered, both based on Hodgkin-Huxley dynamics, self-bursting and adapting. The closed-loop system is simulated and the pendulum oscillation is observed to indicate under which conditions the oscillation entrains to the pendulum's mechanical resonance frequency. We find that entrainment depends on the configuration (negative/positive feedback and excitatory/inhibitory connections) and the ratio of pendulum resonant frequency to RIO intrinsic frequency. This is true of both neuron models, although the exact quantities and regions of entrainment vary between the two.

Ventilation removing and spreading contaminants. A large number of people becoming sick due to the COVID -19 pandemic are infected in their homes. Therefore, the spread of infectious agents, when infectious and susceptible individuals are together in their homes, is an important issue. Usually, ventilation is regarded as a process of only diluting and removing contaminants, but it is also a mechanism for spreading contaminants. The latter issue is of major importance when there is a pandemic. An air distribution system must, therefore, be viewed from a wider perspective than is generally the case. There is a need for a shift of paradigm. The scope of this study is to introduce new concepts that will make it possible to analyze air distribution systems from such a wider perspective.

Submarine debris flows are among the largest types of landslide on planet Earth. They occur under the cloak of the sea so little is known about how they reach such large volumes. Field evidence suggests that the entrainment from the sediment-rich sea floor enables the growth of submarine debris flows. However, there is a dearth of understanding of the dynamic processes of entrainment. In this study, a new entrainment model is proposed for submarine debris flows with different clay contents. The entrainment model considers the relative contributions from basal grain friction and fluid viscous stresses that drive the entrainment process, and the effects of hydroplaning. To evaluate the new model, a new experimental setup is developed to simulate submarine debris flows, with clay contents from 4% to 12%, overriding and entraining a loose sand bed. The clay content is found to have profound effects on the entrainment dynamics. Flows with high clay contents (i.e., ≥10%) hydroplane, which enhances the mobility of the flow but reduces its entrainment potential. The predicted entrainment depths from the proposed model are consistent with the measured ones from the experiments. The proposed theoretical model and unique experimental evidence can be used as guiding tools to progress toward the inclusion of entrainment in vulnerability assessments of offshore infrastructure. © 2022. American Geophysical Union. All Rights Reserved.

Resonance, a powerful and pervasive phenomenon, appears to play a major role in human interactions. This article investigates the relationship between the physical mechanism of resonance and the human experience of resonance, and considers possibilities for enhancing the experience of resonance within human–robot interactions. We first introduce resonance as a widespread cultural and scientific metaphor. Then, we review the nature of “sympathetic resonance” as a physical mechanism. Following this introduction, the remainder of the article is organized in two parts. In part one, we review the role of resonance (including synchronization and rhythmic entrainment) in human cognition and social interactions. Then, in part two, we review resonance-related phenomena in robotics and artificial intelligence (AI). These two reviews serve as ground for the introduction of a design strategy and combinatorial design space for shaping resonant interactions with robots and AI. We conclude by posing hypotheses and research questions for future empirical studies and discuss a range of ethical and aesthetic issues associated with resonance in human–robot interactions., Design Aesthetics, Human Information Communication Design

A series of modifications to the stratocumulus cloud turbulence and entrainment parametrizations in the Open Integrated Forecasting System (OpenIFS) model are performed in a Lagrangian single-column model framework to determine whether they are able to improve the representation of the stratocumulus-topped boundary layer and its transition to cloud break-up. Two very different regimes are studied and compared with large-eddy simulations: a subtropical marine stratocumulus-to-cumulus transition case driven by a warming sea-surface temperature, and an Arctic air-mass transformation case where warm and moist air is advected over sea ice during wintertime. The addition of nonlocal mixing driven by stratocumulus cloud-top cooling for stable and dry convective boundary-layer types is found to sustain the cloud deck for longer in the Arctic case, while it dissipates around one day earlier in the original OpenIFS. The assumption that cloud-top-driven mixing reaches the surface, forming a coupled boundary layer, is relaxed. The resulting eddy diffusivity profile is altered such that mixing at cloud top may be enhanced relative to cloud base, promoting decoupling. Decoupling in the subtropical boundary layer is further promoted when the cloud-top turbulent velocity scale is based on the integral of the in-cloud buoyancy flux, accounting for the turbulence generated by latent heat release within the cloud, which increases cloud-top entrainment further relative to cloud base. Some long-standing model issues persist, such as underestimation of the subtropical boundary-layer deepening rate, which leads to a cold and moist bias in the boundary layer. In the Arctic, the boundary layer is generally too well mixed and warm at the surface. The degree of decoupling is also underestimated in both cases. However, the modifications discussed here lead to some improvement in OpenIFS.

Author Posting. © American Meteorological Society, 2022. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 52(8), (2022): 1705-1730, https://doi.org/10.1175/jpo-d-21-0243.1., Formation and evolution of barrier layers (BLs) and associated temperature inversions (TIs) were investigated using a 1-yr time series of oceanic and air–sea surface observations from three moorings deployed in the eastern Pacific fresh pool. BL thickness and TI amplitude showed a seasonality with maxima in boreal summer and autumn when BLs were persistently present. Mixed layer salinity (MLS) and mixed layer temperature (MLT) budgets were constructed to investigate the formation mechanism of BLs and TIs. The MLS budget showed that BLs were initially formed in response to horizontal advection of freshwater in boreal summer and then primarily maintained by precipitation. The MLT budget revealed that penetration of shortwave radiation through the mixed layer base is the dominant contributor to TI formation through subsurface warming. Geostrophic advection is a secondary contributor to TI formation through surface cooling. When the BL exists, the cooling effect from entrainment and the warming effect from detrainment are both significantly reduced. In addition, when the BL is associated with the presence of a TI, entrainment works to warm the mixed layer. The presence of BLs makes the shallower mixed layer more sensitive to surface heat and freshwater fluxes, acting to enhance the formation of TIs that increase the subsurface warming via shortwave penetration., SK is supported by JSPS Overseas Research Fellowships. JS and SK are supported by NASA Grant 80NSSC18K1500. JTF and the mooring deployment were funded by NASA Grants NNX15AG20G and 80NSSC18K1494. DZ is supported by NASA Grant 80NSSC18K1499. This publication is partially funded by the Cooperative Institute for Climate, Ocean, and Ecosystem Studies (CICOES) under NOAA Cooperative Agreement NA20OAR4320271, Contribution 2021-1152. This is PMEL Contribution 5268., 2023-01-27

Author Posting. © American Meteorological Society, 2022. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 52(3), (2022): 363–382, https://doi.org/10.1175/jpo-d-21-0084.1., Meltwater from Greenland is an important freshwater source for the North Atlantic Ocean, released into the ocean at the head of fjords in the form of runoff, submarine melt, and icebergs. The meltwater release gives rise to complex in-fjord transformations that result in its dilution through mixing with other water masses. The transformed waters, which contain the meltwater, are exported from the fjords as a new water mass Glacially Modified Water (GMW). Here we use summer hydrographic data collected from 2013 to 2019 in Upernavik, a major glacial fjord in northwest Greenland, to describe the water masses that flow into the fjord from the shelf and the exported GMWs. Using an optimum multi-parameter technique across multiple years we then show that GMW is composed of 57.8% ± 8.1% Atlantic Water (AW), 41.0% ± 8.3% Polar Water (PW), 1.0% ± 0.1% subglacial discharge, and 0.2% ± 0.2% submarine meltwater. We show that the GMW fractional composition cannot be described by buoyant plume theory alone since it includes lateral mixing within the upper layers of the fjord not accounted for by buoyant plume dynamics. Consistent with its composition, we find that changes in GMW properties reflect changes in the AW and PW source waters. Using the obtained dilution ratios, this study suggests that the exchange across the fjord mouth during summer is on the order of 50 mSv (1 Sv ≡ 106 m3 s−1) (compared to a freshwater input of 0.5 mSv). This study provides a first-order parameterization for the exchange at the mouth of glacial fjords for large-scale ocean models., This work was partially supported by the Centre for Climate Dynamics (SKD) at the Bjerknes Centre for Climate Research. The authors thank NASA and the OMG consortium for making observational data freely available, and acknowledge M. Morlighem for good support in the early stages of this project. MM and LHS and would also like to thank Ø. Paasche, the ACER project, and the U.S. Norway Fulbright Foundation for the Norwegian Arctic Chair Grant 2019–20 that made the visit to Scripps Institution of Oceanography possible. FS acknowledges support from the DOE Office of Science Grant DE-SC0020073, Heising-Simons Foundation and from NSF and OCE-1756272. DAS acknowledges support from U.K. NERC Grants NE/P011365/1, NE/T011920/1, and NERC Independent Research Fellowship NE/T011920/1. MW was supported by an appointment to the NASA Postdoctoral Program at the Jet Propulsion Laboratory, California Institute of Technology, administered by the Universities Space Research Association under contract with NASA. CSA would like to acknowledge Geocenter Denmark for support to the project “Upernavik Glacier.”

To survive and reproduce, a cell must process information from its environment and its own internal state and respond accordingly, in terms of metabolic activity, gene expression, movement, growth, division and differentiation. These signal-response decisions are made by complex networks of interacting genes and proteins, which function as biochemical switches and clocks, and other recognizable information-processing circuitry. This theme issue of Interface Focus (in two parts) brings together articles on time-keeping and decision-making in living cells-work that uses precise mathematical modelling of underlying molecular regulatory networks to understand important features of cell physiology. Part I focuses on time-keeping: mechanisms and dynamics of biological oscillators and modes of synchronization and entrainment of oscillators, with special attention to circadian clocks.

Global Navigation Satellite Systems (GNSS) satellites are constantly orbiting the Earth in a Medium Earth Orbit (MEO) at an altitude of approximately 20,200 km. GNSS satellites in MEO continuously direct signals towards Earth for terrestrial users, but some signals are bent or refracted back into space. Low Earth Orbiting (LEO) satellites equipped with the proper equipment can receive these radio occultations (RO) and transmit them to ground stations for processing and dissemination. RO data produces profiles or atmospheric soundings of water vapor, temperature, and pressure. This research uses RO profiles to expose the uncertainty of moisture in the tropical troposphere. The tropical troposphere’s moisture uncertainty is critical for determining if convection occurs and assessing updraft strength and buoyancy in the planetary boundary layer to determine intensity. Moisture uncertainty above the planetary boundary layer impacts how detrimental entrainment can be for the generation of thunderstorms. Cloud Model 1 (CM1) numerical simulations demonstrate how moisture uncertainty will affect thunderstorm forecasts. Quantifying uncertainty in the tropical troposphere and demonstrating its effects is critical for improving forecasts in the tropics, where the Navy is commonly operating., Lieutenant Commander, United States Navy, Approved for public release. Distribution is unlimited.

Music's deeply interpersonal nature suggests that music-derived neuroplasticity relates to interpersonal temporal dynamics, or synchrony. Interpersonal neural synchrony (INS) has been found to correlate with increased behavioral synchrony during social interactions and may represent mechanisms that support them. As social interactions often do not have clearly delineated boundaries, and many start and stop intermittently, we hypothesize that a neural signature of INS may be detectable following an interaction. The present study aimed to investigate this hypothesis using a pre-post paradigm, measuring interbrain phase coherence before and after a cooperative dyadic musical interaction. Ten dyads underwent synchronous electroencephalographic (EEG) recording during silent, non-interactive periods before and after a musical interaction in the form of a cooperative tapping game. Significant post-interaction increases in delta band INS were found in the post-condition and were positively correlated with the duration of the preceding interaction. These findings suggest a mechanism by which social interaction may be efficiently continued after interruption and hold the potential for measuring neuroplastic adaption in longitudinal studies. These findings also support the idea that INS during social interaction represents active mechanisms for maintaining synchrony rather than mere parallel processing of stimuli and motor activity.

This is the peer reviewed version of the following article: Kawashima, T., Shibusawa, S., & Amano, K. (2022). Frequency- and phase-dependent effects of auditory entrainment on attentional blink. European Journal of Neuroscience, 56(4), 4411– 4424, which has been published in final form at https://doi.org/10.1111/ejn.15760. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited., Attentional blink (AB) is the impaired detection of a second target (T2) after a first target has been identified. In this paper, we investigated the functional roles of alpha and theta oscillations on AB by determining how much preceding rhythmic auditory stimulation affected the performance of AB. Healthy young adults participated in the experiment online. We found that when two targets were embedded in rapid serial visual presentation (RSVP) of distractors at 10 Hz (i.e., alpha frequency), the magnitude of AB increased with auditory stimuli. The increase was limited to the case when the frequency and phase of auditory stimuli matched the following RSVP stream. On the contrary, when only two targets were presented without distractors, auditory stimuli at theta, not alpha, increased the AB magnitude. These results indicate that neural oscillations at two different frequencies, namely, alpha and theta, are involved in attentional blink.

Neural mechanisms supporting time perception in continuously changing sensory environments may be relevant to a broader understanding of how the human brain utilizes time in cognition and action. In this review, we describe current theories of sensorimotor engagement in the support of subsecond timing. We focus on musical timing due to the extensive literature surrounding movement with and perception of musical rhythms. First, we define commonly used but ambiguous concepts including neural entrainment, simulation, and prediction in the context of musical timing. Next, we summarize the literature on sensorimotor timing during perception and performance and describe current theories of sensorimotor engagement in the support of subsecond timing. We review the evidence supporting that sensorimotor engagement is critical in accurate time perception. Finally, potential clinical implications for a sensorimotor perspective of timing are highlighted.

In small musical groups, performers can seem to coordinate their movements almost effortlessly in remarkable exhibits of joint action and entrainment. To achieve a common musical goal, co-performers interact and communicate using non-verbal means such as upper-body movements, and particularly head motion. Studying these phenomena in naturalistic contexts can be challenging since most techniques make use of motion capture technologies that can be intrusive and costly. To investigate an alternative method, we analyze video recordings of a professional instrumental ensemble by extracting trajectory information using pose estimation algorithms. We examine Kansei perspectives such as the analysis of non-verbal expression conveyed by bodily movements and gestures, and test for causal relationships and directed influence between performers using the Granger Causality method. We compute weighted probabilities representing the likelihood that each performer Granger Causes co-performers’ movements. Effects of different aspects of musical textures were examined and results indicated stronger directionality for homophonic textures (clear melodic leader) than polyphonic (ambiguous leadership).

Continuous interactions between physiological body-brain rhythms influence how individuals act, perceive, and evaluate their environment. Despite increasing interest, the intricate interface between breathing, cardiac, neural rhythms, and cognitive function remains poorly understood. By evaluating current theoretical and empirical implications, we derive an integrative framework of a 'body-brain dynamic system' that combines a hidden hierarchical structure with dynamical state transitions. We propose that body-brain signals can interchangeably drive state- and task-specific coupling mechanisms which influence cognitive functions. The dynamical nature of this framework parallels the intrinsic variability of human behavior, and ultimately aims at better understanding how individuals act in and adapt to a dynamically changing environment.

Forest wildfires leave vast areas with burned topsoil that is water repellent, susceptible to erosion by surface runoff and a potential source of debris flow. To mitigate post-fire debris flow hazards, debris resisting barriers are usually constructed in the flow path. However, the fundamental interaction mechanisms of debris flow on a water repellent bed and the momentum exchange process that governs the destructive potential of debris flows have yet to be elucidated. This study investigates the influence of bed sediment hydrophobicity on entrainment by debris flows and the impact force on a downstream barrier using a series of physical flume tests. Bed sediment with increasing contact angles (50°–130°) were used to model bed hydrophobicity from wettable to hydrophobic conditions, and volumetric water content (0%–30%) to simulate the natural unsaturated condition after rainfall in fire-burned hillslopes. Compared to a wettable bed, a hydrophobic bed exhibits a failure pattern with slab-by-slab entrainment and en masse failure with a sixfold increase in the average erosion depth. A new dimensionless number is proposed to quantify the effects of contact angle on soil erosion. The flow momentum increases up to 21% after entrainment of hydrophobic bed compared to non-erodible bed. The peak impact force on the downstream barrier can increase up to 80% for hydrophobic bed as a consequence of momentum gains after entrainment. The hydrodynamic coefficient for estimating impact force reveals the inadequacy of current design criteria of debris resisting barriers for fire-prone vegetated hillslopes, suggesting further investigations are needed. © 2022. American Geophysical Union. All Rights Reserved.

Peer Reviewed

To survive and reproduce, a cell must process information from its environment and its own internal state and respond accordingly, in terms of metabolic activity, gene expression, movement, growth, division and differentiation. These signal–response decisions are made by complex networks of interacting genes and proteins, which function as biochemical switches and clocks, and other recognizable information-processing circuitry. This theme issue of Interface Focus (in two parts) brings together articles on time-keeping and decision-making in living cells—work that uses precise mathematical modelling of underlying molecular regulatory networks to understand important features of cell physiology. Part I focuses on time-keeping: mechanisms and dynamics of biological oscillators and modes of synchronization and entrainment of oscillators, with special attention to circadian clocks., SCOPUS: ar.j, info:eu-repo/semantics/published

Affective well-being of employees is a key outcome in the occupational health literature. Yet, researchers of emotions and affect have long called for a better understanding of the dynamic nature of such experiences. Directly addressing this call, we have built on temporal schema theories and the notion of temporal depth to develop and test the anticipation of work account as a theoretical explanation of systematic weekly change patterns in positive and negative affect. Using a 7-day experience-sampling design and latent growth curve modeling, we hypothesized and found that anticipation of work linearly decreased over the course of the workweek, so did negative affect. Supporting our hypothesis that change patterns in work anticipation drive change patterns in evening affect, the linear change trajectory of anticipation was significantly related to change trajectories in positive and negative affect. Furthermore, we identified the structure of the workweek and chronic workload as boundary conditions that interact in shaping weekly change patterns in anticipation. Specifically, patterns of decreasing anticipation were most pronounced for employees with a regular Monday-Friday workweek and high chronic levels of workload, while they were weakest for employees with a regular workweek but low levels of chronic workload. Taken together, our results highlight the role of work itself and working conditions in dynamic aspects of affect. They yield theoretical and practical implications for the study of affect and its work-related experiential and behavioral consequences.

Mammals have evolved circadian rhythms in internal biological processes and behaviors, such as locomotor activity (LA), to synchronize to the environmental conditions they experience. Photic entrainment of LA has been well established; however, non-photic entrainment, such as ambient temperature (Ta), has received much less attention. To address this dearth of knowledge, we exposed two subterranean endothermic-homeothermic African mole-rat species, the solitary Cape mole-rat (Georychus capensis [GC]) and social Mahali mole-rat (Cryptomys hottentotus mahali [CHM]), to varying Ta cycles in the absence of light. We showed that the LA rhythms of these two species entrain to Ta cycles and that the majority of LA occurred during the coolest 12-h period. LA confined to the coolest Ta periods may be the direct consequence of the poor heat dissipation abilities of African mole-rats brought about by physiological and ecological constraints. Recently, it has been hypothesized that Ta is only a strong zeitgeber for circadian rhythms in species whose thermoregulatory abilities are sensitive to changes in Ta (i.e., heterotherms and ectotherms), which previously has excluded endothermic-homeothermic mammals. However, this study demonstrates that Ta is a strong zeitgeber or entrainer for circadian rhythms of LA in subterranean endothermic-homeothermic mammals as a consequence of their sensitivity to changes in Ta brought about by their poor heat dissipation abilities. This study reinforces the intimate link between circadian rhythms and thermoregulation and conclusively, for the first time, provides evidence that Ta is a strong zeitgeber for endothermic-homeothermic mammals.

Among many issues, in The Life and Opinions of Tristram Shandy, Gentleman (1759 - 1767, Tristram Shandy from here onwards) Laurence Sterne explores through the narrative voice of Tristram the subjects of writing, reading, and the reader’s experience. Wolfgang Iser in The Act of Reading explores in 1994 the same phenomenon from a theoretical perspective. In this BA Thesis, a qualitative analysis of the former using the theoretical tools of the latter has been carried out with a double focus. First, the process of entrainment has been used to describe the different gaits that Tristram aims to impart on readers. According to this view, Tristram seems to be trying to make readers conscious of their different reading approaches. Then, the blank page of the widow Wadman has been analysed as a blank that triggers and controls the reader’s activity., Entre otras cuestiones, The Life and Opinions of Tristram Shandy, Gentleman (1759 - 1767, Tristram Shandy de aquí en adelante) de Laurence Sterne explora a través de la voz narrativa de Tristram los temas de la escritura, la lectura y la experiencia del lector. En The Act of Reading (1994), Wolfgang Iser explora el mismo fenómeno a través de una perspectiva teórica. En este Trabajo de Fin de Grado se ha llevado a cabo un análisis cualitativo del primero utilizando las herramientas teóricas del segundo con un doble objetivo. Primero, el proceso de entrainment o ‘inducción al ritmo’ se ha usado para describir las diferentes marchas que Tristram intenta impartir sobre sus lectores (en búsqueda de conocimiento o aventuras). Según este punto de vista, Tristram intenta hacer conscientes a los lectores de los diferentes estilos de lectura. Después, la página en blanco de la viuda Wadman ha sido analizado como un espacio en blanco que origina y controla la actividad de los lectores., Grado en Estudios Ingleses