Temporal Adaptation Research Articles

Pressure tolerance of brine shrimp (Artemia)

ABSTRACT Life adapts to various environments, including high temperatures and high pressures. The brine shrimp Artemia was used to investigate the tolerance to hydrostatic pressure up to 750 bar. The swimming activity of Artemia nauplii (larval form) decreased as pressure increased, and the activity became null at 400 bar and above. Interestingly, at 300 bar and less, the swimming activity gradually recovered even under pressure within a short period of time. Up to 500 bar, the activity was reversibly recovered by reducing the pressure to 1 bar. These results could be explained by reversible responses of protein functions and membrane structures, as well as temporal adaptation of cell functions to pressure. The upper limit pressure at which the swimming activity was reversible or irreversible matched that for macromolecular synthesis (500 bar). Altogether, these results indicate that eukaryotes and prokaryotes can temporarily adapt to a high pressure of 500 bar and less.

Adaptively Meshed Video Stabilization

Video stabilization is essential for improving the visual quality of shaky videos. Current video stabilization methods usually take feature trajectories in the background to estimate one global transformation matrix or several transformation matrices based on a fixed mesh, and warp shaky frames into their stabilized views. However, these methods may not model the shaky camera motion well in complicated scenes, such as scenes containing large foreground objects or strong parallax, and may result in notable visual artifacts in the stabilized videos. To resolve the above issues, this paper proposes an adaptively meshed method to stabilize a shaky video based on all of its feature trajectories and an adaptive blocking strategy. More specifically, we first extract the feature trajectories of the shaky video and then generate a triangle mesh according to the distribution of the feature trajectories in each frame. Then, the transformations between shaky frames and their stabilized views over all triangular grids of the mesh are calculated to stabilize the shaky video. Since more feature trajectories can usually be extracted from all of the regions, including both the background and foreground regions, a finer mesh will be obtained and provided for camera motion estimation and frame warping. We estimate the mesh-based transformations of each frame by solving a two-stage optimization problem. Moreover, foreground and background feature trajectories are no longer distinguished and both contribute to the estimation of the camera motion in the proposed optimization problem, yielding better estimation performance than previous works, particularly in challenging videos with large foreground objects or strong parallax. To further enhance the robustness of our method, we propose two adaptive weighting mechanisms to improve its spatial and temporal adaptability. Experimental results demonstrate the effectiveness of our method in producing visually pleasing stabilization effects in various challenging videos.

Gaze-Dependent Simulation of Light Perception in Virtual Reality.

The perception of light is inherently different inside a virtual reality (VR) or augmented reality (AR) simulation when compared to the real world. Conventional head-worn displays (HWDs) are not able to display the same high dynamic range of brightness and color as the human eye can perceive in the real world. To mimic the perception of real-world scenes in virtual scenes, it is crucial to reproduce the effects of incident light on the human visual system. In order to advance virtual simulations towards perceptual realism, we present an eye-tracked VR/AR simulation comprising effects for gaze-dependent temporal eye adaption, perceptual glare, visual acuity reduction, and scotopic color vision. Our simulation is based on medical expert knowledge and medical studies of the healthy human eye. We conducted the first user study comparing the perception of light in a real-world low-light scene to a VR simulation. Our results show that the proposed combination of simulated visual effects is well received by users and also indicate that an individual adaptation is necessary, because perception of light is highly subjective.

Horizontal Cell Feedback to Cone Photoreceptors in Mammalian Retina: Novel Insights From the GABA-pH Hybrid Model.

How neurons in the eye feed signals back to photoreceptors to optimize sensitivity to patterns of light appears to be mediated by one or more unconventional mechanisms. Via these mechanisms, horizontal cells control photoreceptor synaptic gain and enhance key aspects of temporal and spatial center-surround receptive field antagonism. After the transduction of light energy into an electrical signal in photoreceptors, the next key task in visual processing is the transmission of an optimized signal to the follower neurons in the retina. For this to happen, the release of the excitatory neurotransmitter glutamate from photoreceptors is carefully regulated via horizontal cell feedback, which acts as a thermostat to keep the synaptic transmission in an optimal range during changes to light patterns and intensities. Novel findings of a recently described model that casts a classical neurotransmitter system together with ion transport mechanisms to adjust the alkaline milieu outside the synapse are reviewed. This novel inter-neuronal messaging system carries feedback signals using two separate, but interwoven regulated systems. The complex interplay between these two signaling modalities, creating synaptic modulation-at-a-distance, has obscured it’s being defined. The foundations of our understanding of the feedback mechanism from horizontal cells to photoreceptors have been long established: Horizontal cells have broad receptive fields, suitable for providing surround inhibition, their membrane potential, a function of stimulus intensity and size, regulates inhibition of photoreceptor voltage-gated Ca2+ channels, and strong artificial pH buffering eliminates this action. This review compares and contrasts models of how these foundations are linked, focusing on a recent report in mammals that shows tonic horizontal cell release of GABA activating Cl− and HCO3− permeable GABA autoreceptors. The membrane potential of horizontal cells provides the driving force for GABAR-mediated HCO3− efflux, alkalinizing the cleft when horizontal cells are hyperpolarized by light or adding to their depolarization in darkness and contributing to cleft acidification via NHE-mediated H+ efflux. This model challenges interpretations of earlier studies that were considered to rule out a role for GABA in feedback to cones.

Modulation of cerebellar brain inhibition during temporal adaptive learning in a coincident timing task.

In the present study, we examined the role of the cerebellum in temporal adaptive learning during a coincident timing task, i.e., a baseball-like hitting task involving a moving ball presented on a computer monitor. The subjects were required to change the timing of their responses based on imposed temporal perturbations. Using paired-pulse transcranial magnetic stimulation, we measured cerebellar brain inhibition (CBI) before, during, and after the temporal adaptive learning. Reductions in CBI only occurred during and after the temporal adaptive learning, regardless of the direction of the temporal perturbations. In addition, the changes in CBI were correlated with the magnitude of the adaptation. Here, we showed that the cerebellum is essential for learning about and controlling the timing of movements during temporal adaptation. Furthermore, changes in cerebellar-primary motor cortex connectivity occurred during temporal adaptation, as has been previously reported for spatial adaptation.

ИЗУЧЕНИЕ ФАКТОРОВ ВРЕМЕННОЙ АДАПТИВНОСТИ У ЛИЦ С РАЗНЫМ УРОВНЕМ ЗДОРОВЬЯ

The article presents the results of a study of factors, features and the level of development of temporary adaptability, as an ability and resource for adaptation, in people with different levels of health. The study was conducted by the method of interviewing in full-time and electronic forms on a sample of people from a conditionally healthy group and having health problems of different nosological groups. In the course of the analysis of the research results, such factors of a person’s temporal adaptability as perception and orientation in time, adaptation to natural temporal changes, adaptation to changes in plans, daily ritual routines and schedules were highlighted. The novelty of the research results is the allocation of temporary adaptability, as a form of adaptability to the physical conditions of the environment, as a separate subject of study and the study of its factors, features and level of development in people with different levels of health. The results can be applied in the development of training courses, including in remote form, for the development of skills of perception and orientation in time, planning and time management. Also, the results of the study are important for the development of methods for determining the level of adaptability of a person to the physical structure of the environment.

A circuit model of auditory cortex.

The mammalian sensory cortex is composed of multiple types of inhibitory and excitatory neurons, which form sophisticated microcircuits for processing and transmitting sensory information. Despite rapid progress in understanding the function of distinct neuronal populations, the parameters of connectivity that are required for the function of these microcircuits remain unknown. Recent studies found that two most common inhibitory interneurons, parvalbumin- (PV) and somatostatin-(SST) positive interneurons control sound-evoked responses, temporal adaptation and network dynamics in the auditory cortex (AC). These studies can inform our understanding of parameters for the connectivity of excitatory-inhibitory cortical circuits. Specifically, we asked whether a common microcircuit can account for the disparate effects found in studies by different groups. By starting with a cortical rate model, we find that a simple current-compensating mechanism accounts for the experimental findings from multiple groups. They key mechanisms are two-fold. First, PVs compensate for reduced SST activity when thalamic inputs are strong with less compensation when thalamic inputs are weak. Second, SSTs are generally disinhibited by reduced PV activity regardless of thalamic input strength. These roles are augmented by plastic synapses. These roles reproduce the differential effects of PVs and SSTs in stimulus-specific adaptation, forward suppression and tuning-curve adaptation, as well as the influence of PVs on feedforward functional connectivity in the circuit. This circuit exhibits a balance of inhibitory and excitatory currents that persists on stimulation. This approach brings together multiple findings from different laboratories and identifies a circuit that can be used in future studies of upstream and downstream sensory processing.

Exercise of Dynamic Stability in the Presence of Perturbations Elicit Fast Improvements of Simulated Fall Recovery and Strength in Older Adults: A Randomized Controlled Trial.

Age-related impairments of reactive motor responses to postural threats and reduced muscular capacities of the legs are key factors for the higher risk of falling in older people. It has been evidenced that a training of dynamic stability in the presence of perturbations has the potential to improve these deficits. However, the time course of training effects during such interventions is poorly understood. The purpose of this parallel-group study was to investigate the temporal adaptation dynamics of the balance recovery performance and leg strength during a dynamic stability training. Forty-two healthy older adults (65–85 years) were randomly assigned to a training (n = 27, analyzed n = 18) or control group (n = 15, n = 14). The training was conducted in a group setting for 6 weeks (3×/week, 45 min). The exercises focused on the mechanism of stability control (i.e., modulation of the base of support and segment counter-rotations around the center of mass) during standing, stepping, and jumping on unstable surfaces with a high balance intensity. Before, after 3 and after 6 weeks, the maximum plantar flexion moment and the knee extension moment were assessed. The recovery performance was evaluated by a simulated forward fall (lean-and-release test) and the margin of stability concept. The margin of stability at release decreased significantly after 3 weeks of training (34%, effect size g = 0.79), which indicates fast improvements of balance recovery performance. The margin of stability further decreased after week 6 (53%, g = 1.21), yet the difference between weeks 3 and 6 was not significant. Furthermore, the training led to significant increases in the plantar flexion moment after weeks 3 (12%, g = 0.72) and 6 (13%, g = 0.75) with no significant difference between weeks. For the knee extension moment, a significant increase was found only after week 6 (11%, g = 1.07). The control group did not show any significant changes. This study provides evidence that a challenging training of dynamic stability in the presence of perturbations can improve balance recovery performance and leg strength of older adults already after a few weeks. Therefore, short-term training interventions using this paradigm may be an effective strategy for fall prevention in the elderly population, particularly when intervention time is limited.

A new model for total electron content based on ionospheric continuity equation

With the development of the Global Navigation Satellite System (GNSS), the accuracy and reliability requirements on observations are constantly increasing. The effect of ionospheric disturbance is not negligible, especially for accurate GNSS applications. To reduce the influence of ionospheric delay and disturbance, this study uses the Ionospheric Continuity Equation (ICE) to establish a new model for Total Electron Content (TEC), which takes both photochemical and transportation processes into account and named ICE model. Experimental results show that the ICE model achieves accuracies higher than Spherical Harmonic (SH) and polynomial models on geomagnetism quiet and disturbance days, and more prominent advantages appear at nighttime. By the test of Satellite Differential Code Bias (SDCB) estimation, the deviations of the polynomial and the ICE models are nearly the same whatever the geomagnetic field is quiet or disturbance; however, the estimation accuracy of the ICE model is slightly better than the polynomial model. Spatial and temporal adaptability tests indicate that the ICE model can achieve accuracies of 0.5 TECU and 1 TECU on time scales of approximately 25 min and 100 min, respectively. On the weak disturbance or quiet day, these accuracies can be achieved on the spatial scales of approximately 200 km and 600 km. The credibility of the ICE model is evaluated by Nash–Sutcliffe efficiency. The evaluation results assigned that the ICE model has higher credibility than the SH and polynomial models and better immunity to geomagnetic disturbance.

Adaptation strategies based on the historical evolution for dairy production systems in temperate areas: A case study approach

Dairy production systems are heterogeneous as they are influenced by farm location and structure, markets, environmental conditions, and the producers' preferences and peculiarities. A typology of the existing dairy systems in Chile was developed with the objective of identifying homogenous groups that would allow for the characterization of adaptation strategies to changing environmental, social, technological, political and economic variables. Multivariate analyses were performed on data from official surveys carried out in 2009, 2011, 2013, and 2015. Six groups (I-VI) were identified representing 26.9%, 21.5%, 21.6%, 14.6%, 6.8% and 8.6% of the population surveyed. Group I was the largest, and it included non-specialized commercial dairies. Group II clustered semi-extensive, medium to large dairies that rely mostly on high yielding improved pastures. Group III included small, semi-extensive commercial farms that make a more intense use of pastoral resources, such as sown pastures and improved native grasslands. Groups IV, V, and VI corresponded to specialized dairies, highly market-oriented, that use annual forages to supplement intensively managed and planned pastures, but that differ in size and some management strategies. The observed temporal changes and adaptations over time were closely linked to farm size, intensity in the use of various technologies, the number and the breed of the dairy cows, and the presence of other agricultural activities in the property. The effect of variable prices of milk and system inputs differed by group. Given the social and economic importance of dairies throughout Central and Southern Chile, a number of interventions are proposed, including technical modifications, extension initiatives, and changes in policies.

Robustness and efficiency of an implicit time-adaptive discontinuous Galerkin solver for unsteady flows

High-fidelity fluid dynamics simulations of unsteady flows are nowadays of great interest for many industrial fields. This class of simulations, as they are characterized by a wide range of temporal scales, requires robust, accurate and efficient long time integration strategies. These features can be achieved by an appropriate coupling of high-order time integration schemes and time-step adaptation algorithms. The adaptation algorithms are typically based on a local error estimator, which exploits the local truncation error of the time integration scheme and of its lower order embedded scheme.In literature few information are available to assess the benefits in terms of robustness, accuracy, and efficiency provided by the coupling between temporal schemes and adaptation strategies for unsteady CFD simulations. The aim of this work is to reduce this gap, presenting a numerical investigation of the performance for different adaptive time-step strategies, based on implicit Rosenbrock-type temporal schemes, in a high-order discontinuous Galerkin solver.The performance of the considered time integration strategies for the autonomous ODE system resulting from the DG space discretization of the Navier–Stokes equations is assessed for several test cases of increasing stiffness and difficulty, identifying the best scheme and algorithm: (i) the 2D laminar flow around a circular cylinder and around a tandem of cylinders at ReD=100; (ii) the 2D viscous flow through a porous media, modelled as an array of cylinders, at ReD=2100 and ReD=10,000; (iii) the 3D turbulent flow through a 4-wheels rudimentary landing gear (RLG) at ReD=1×106.

Back to the Future – Temporal Adaptation of Text Representations

Language evolves over time in many ways relevant to natural language processing tasks. For example, recent occurrences of tokens 'BERT' and 'ELMO' in publications refer to neural network architectures rather than persons. This type of temporal signal is typically overlooked, but is important if one aims to deploy a machine learning model over an extended period of time. In particular, language evolution causes data drift between time-steps in sequential decision-making tasks. Examples of such tasks include prediction of paper acceptance for yearly conferences (regular intervals) or author stance prediction for rumours on Twitter (irregular intervals). Inspired by successes in computer vision, we tackle data drift by sequentially aligning learned representations. We evaluate on three challenging tasks varying in terms of time-scales, linguistic units, and domains. These tasks show our method outperforming several strong baselines, including using all available data. We argue that, due to its low computational expense, sequential alignment is a practical solution to dealing with language evolution.

Action-effect anticipation and temporal adaptation in social interactions.

Interacting agents may anticipate their partner's upcoming response and include it in their action plan. In turn, observing an overt response can trigger agents to adapt. But although anticipation and adaptation are known to shape action control, their interplay in social interactions remains largely unexplored. In 4 experiments, we asked how both of these mechanisms could contribute to one striking phenomenon: Agents initiate actions faster when they know their partner will produce a compatible rather than an incompatible response. In Experiment 1, we manipulated the compatibility between agents' actions and partners' responses and investigated the interplay between adaptation and anticipation within the same dyadic interaction. In Experiments 2-4, we isolated the contribution of each mechanism by having agents interact with virtual partners whose responses could be experimentally controlled. We found that adaptation and anticipation exert parallel but independent effects on action execution: Participants initiated their actions more quickly when the upcoming partner response was compatible and, independently, when their partner had responded more quickly on the preceding trial. These findings elucidate models of action control in social interactions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Spatial and temporal adaptation of predictive saccades based on motion inference

Moving objects are often occluded behind larger, stationary objects, but we can easily predict when and where they reappear. Here, we show that the prediction of object reappearance is subject to adaptive learning. When monkeys generated predictive saccades to the location of target reappearance, systematic changes in the location or timing of target reappearance independently altered the endpoint or latency of the saccades. Furthermore, spatial adaptation of predictive saccades did not alter visually triggered reactive saccades, whereas adaptation of reactive saccades altered the metrics of predictive saccades. Our results suggest that the extrapolation of motion trajectory may be subject to spatial and temporal recalibration mechanisms located upstream from the site of reactive saccade adaptation. Repetitive exposure of visual error for saccades induces qualitatively different adaptation, which might be attributable to different regions in the cerebellum that regulate learning of trajectory prediction and saccades.

Increased error-correction leads to both higher levels of variability and adaptation

In order to intercept moving objects, we need to predict the spatiotemporal features of the motion of both the object and our hand. Our errors can result in updates of these predictions to benefit interceptions in the future (adaptation). Recent studies claim that task-relevant variability in baseline performance can help adapt to perturbations, because initial variability helps explore the spatial demands of the task. In this study, we examined whether this relationship is also found in interception (temporal domain) by looking at the link between the variability of hand-movement speed during baseline trials, and the adaptation to a temporal perturbation. 17 subjects performed an interception task on a graphic tablet with a stylus. A target moved from left to right or vice versa, with varying speed across trials. Participants were instructed to intercept this target with a straight forward movement of their hand. Their movements were represented by a cursor that was displayed on a screen above the tablet. To prevent online corrections we blocked the hand from view, and a part of the cursor's trajectory was occluded. After a baseline phase of 80 trials, a temporal delay of 100 ms was introduced to the cursor representing the hand (adaptation phase: 80 trials). This delay initially caused participants to miss the target, but they quickly accounted for these errors by adapting to most of the delay of the cursor. We found that variability in baseline movement velocity is a good predictor of temporal adaptation (defined as a combination of the rate of change and the asymptotic level of change after a perturbation), with higher variability during baseline being associated with better adaptation. However, cross-correlation results suggest that the increased variability is the result of increased error correction, rather than exploration.

Heterogeneous Temporal Contrast Adaptation in Drosophila Direction-Selective Circuits.

In visual systems, neurons adapt both to the mean light level and to the range of light levels, or the contrast. Contrast adaptation has been studied extensively, but it remains unclear how it is distributed among neurons in connected circuits, and how early adaptation affects subsequent computations. Here, we investigated temporal contrast adaptation in neurons across Drosophila's visual motion circuitry. Several ON-pathway neurons showed strong adaptation to changes in contrast over time. One of these neurons, Mi1, showed almost complete adaptation on fast timescales, and experiments ruled out several potential mechanisms for its adaptive properties. When contrast adaptation reduced the gain in ON-pathway cells, it was accompanied by decreased motion responses in downstream direction-selective cells. Simulations show that contrast adaptation can substantially improve motion estimates in natural scenes. The benefits are larger for ON-pathway adaptation, which helps explain the heterogeneous distribution of contrast adaptation in these circuits.

Estimation of genetic parameters and selection of Coffea canephora progenies evaluated in Brazilian Western Amazon

Coffee has emerged as an economic alternative culture in the State of Acre, Brazil, but without a clonal variety recommended for the state to overcome the unevenness presented by seed crops. Thus, in order to estimate genetic parameters and indicate progenies of Coffea canephora to compose a clonal variety for the State of Acre, yield, vegetative vigor and plant height were evaluated in five harvests of a randomized complete block experiment with 46 progenies, 4 repetitions and 10 plants per plot by mixed model methodology (REML/BLUP). The harvests were evaluated individually, by the model that considers one harvest, one location and the mean of progenies, and joint analysis (all harvests), by repeatability model with stability and temporal adaptability by the harmonic mean of relative performance of genotypic values method (MHPRVG), with genotypic values of progenies grouped by the Tocher method. There was variability, with possibility of selection, only for grain yield. The yield was strongly affected by production bienniality, with high environmental influence and harvests mean ranging from 14.13±4.60 to 46.20±14.94 bags ha-1 and individual heritabilities from 0.10 to 0.44. Sixteen ‘Conilon’ coffee progenies with selection gains above 23% were selected. The MHPRVG method allows the refinement of progeny selection throughout the harvests, identifying the most adapted and stable. Key words: ‘Conilon’ or ‘Kouilou’ coffee; Breeding; Mixed models.

Supplemental Material for Action–Effect Anticipation and Temporal Adaptation in Social Interactions

Supplemental Material for Action–Effect Anticipation and Temporal Adaptation in Social Interactions

Biomechanical pathways of dentoalveolar fibrous joints in health and disease.

Spatial and temporal adaptations within periodontal tissues and their interfaces result from functional loads. Functional loads can be physiologic and/or pathologic in nature. The prolonged effect of these loads can alter the overall biomechanics of a dentoalveolar fibrous joint (dentoalveolar joint) by changing the form of the tooth root and its socket. This "sculpting" of the tooth root and alveolar bony socket is a consequence of several mechano-biological changes that occur within the periodontal complex of a load-bearing dentoalveolar joint. These include changes in biochemical expressions, structure, elemental composition, and mechanical properties of alveolar bone, the underlying tissues of the roots of teeth, and their interfaces. These physicochemical changes in tissues continue to prompt mechano-responsive biochemical activities at the attachment sites of periodontal ligament (soft) with bone (hard), and ligament with cementum (hard), which are the entheses of a load-bearing dentoalveolar joint. Forces at soft-hard tissue attachment sites between disparate materials with different stiffness values theoretically generate strain singularities or discontinuities. These discontinuities under prolonged functional loading increase the probability for failure to occur specifically at the enthesial zones. However, in a normal dentoalveolar joint, gradual stiffness gradients exist from ligament to bone, and from ligament to cementum. The gradual transitions in stiffness from softer ligament (lower stiffness) to harder bone or cementum (higher stiffness) or vice versa optimize tissue and interfacial strains. Optimization of tissue and ligament-enthesial physical and chemical properties facilitates transmission of cyclic forces of varying magnitudes and frequencies that collectively maintain the overall biomechanics of a dentoalveolar joint. The objectives of this review are 3-fold: (i) to illustrate physicochemical adaptations at the periodontal ligament entheses of a human periodontal complex affected by subgingival calculus; (ii) to demonstrate how to "program" the hallmarks of periodontitis in small-scale vertebrates in vivo to generate spatiotemporal maps of physicochemical adaptations in a diseased dentoalveolar joint; and (iii) to correlate dentoalveolar joint biomechanics in healthy and diseased states to spatiotemporal maps of physicochemical adaptations within respective periodontal tissues. This interdisciplinary approach demonstrates that physicochemical adaptations within periodontal tissues using the mechanics of materials (tissue mechanics), materials science (tissue composition), and mechano-biology (matrix molecules) can help explain the mechano-adaptation of dentoalveolar joints in normal and diseased functional states. Multiscale biomechanics and mechano-biology approaches can provide insights into the functional competence of a diseased relative to a normal dentoalveolar joint. Insights gathered from interdisciplinary and multiscale biomechanics approaches include the following: (i) physiologic loads related to chewing maintain a balance between mineral-forming and-resorbing biochemical cellular events, resulting in gradual stiffness gradients at the periodontal ligament entheses, and, in turn, sustain the overall biomechanics of a normal "healthy" dentoalveolar joint; (ii) pathologic loads resulting from tissue degradation and physical changes to the periodontal complex promote an abrupt stiffness gradient at the periodontal ligament entheses. The shift from gradual to an abrupt stiffness gradient could prompt a shift in the biochemical cascades, exacerbate mechano-responsive biochemical expressions at periodontal ligament entheses farther away from the site of insult, and culminate in joint degradation; (iii) sustained pathologic function on periodontally diseased joints exacerbates degradation of periodontal ligament entheses providing insights into "rescue therapy", such as the use of an adequate "mechanocal dose" to regain joint function; and (iv) spatiotemporal maps of changes in biochemical expressions, and physicochemical properties of strain-dominated affected sites, including the periodontal ligament entheses, can guide anatomy-specific therapeutics for tissue regeneration and/or disease control with the purpose of regaining dentoalveolar joint function. Modulation of occlusal loads could minimize disease progression and potentially assist in regaining functional attachment of ligament to bone and/or ligament to cementum of the dentoalveolar joint. Elucidating mechanisms that drive the breakdown of the functionally active periodontal complex burdened with microbes will provide the required critical insights into regenerative medicine and/or biomimetic approaches that would facilitate rescue/regain of dentoalveolar joint function.

Disruptions and food consumption in Islamabad

This paper investigates the disruptions in everyday routine and the stresses of food sourcing in the urban food environment among middle class residents of Islamabad, Pakistan. It explores the dynamism of urban food environments in developing countries under the influence of various stressors and highlights adaptations taken by urban consumers. It presents a middle class view of urban food security and explores the potential constraints on food acquisition for a section of the population that has normally considered itself food secure. The paper examines how seasonal scarcities of gas and water, artificial cost inflations during the month of fasting, and regional and local disasters such as floods and militant violence influence food decisions within this group. It pays particular attention to the temporal nature of these disruptions, how they impact perceptions and experiences of food sourcing and the subsequent temporal and spatial adaptations adopted. Specifically, it contributes to the literature on food environments and food security by demonstrating how such disruptions contribute to dynamism within food environments, how the middle class responds to these changes in their everyday lives, and how their perceptions on personal food security are threatened. The paper adds to the literature on the role of time, personal routines, and anticipatory logic in the context of food consumption within a developing country using household-level perspectives of urban food environments.