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Sharp wave-ripple complexes (SPW-Rs) are spontaneous oscillatory events that characterize hippocampal activity during resting periods and slow-wave sleep. SPW-Rs are related to memory consolidation - the process during which newly acquired memories are transformed into long-lasting memory traces. To test the involvement of SPW-Rs in this process, it is crucial to understand how SPW-Rs originate and propagate throughout the hippocampus. SPW-Rs can originate in CA3, and they typically spread from CA3 to CA1, but little is known about their formation within CA3. To investigate the generation and propagation of SPW-Rs in CA3, we recorded from mouse hippocampal slices using multi-electrode arrays and patch-clamp electrodes. We characterized extracellular and intracellular correlates of SPW-Rs and quantified their propagation along the pyramidal cell layer of CA3. We found that a hippocampal slice can be described by a speed and a direction of propagation of SPW-Rs. The preferred propagation direction was from CA3c (the subfield closer to the dentate gyrus) toward CA3a (the subfield at the boundary to CA2). In patch-clamp recordings from CA3 pyramidal neurons, propagation was estimated separately for excitatory and inhibitory currents associated with SPW-Rs. We found that propagation speed and direction of excitatory and inhibitory currents were correlated. The magnitude of the speed of propagation of SPW-Rs within CA3 was consistent with the speed of propagation of action potentials in axons of CA3 principal cells. KEY POINTS: Hippocampal sharp waves are considered important for memory consolidation; therefore, it is of interest to understand the mechanisms of their generation and propagation. Here, we used two different approaches to study the propagation of sharp waves in mouse CA3 in vitro: multi-electrode arrays and multiple single-cell recordings. We find a preferred direction of propagation of sharp waves from CA3c toward CA3a - both in the local field potential and in sharp wave-associated excitatory and inhibitory synaptic activity. The speed of sharp wave propagation is consistent with the speed of action potential propagation along the axons of CA3 pyramidal neurons. These new insights into the dynamics of sharp waves in the CA3 network will inform future experiments and theoretical models of sharp-wave generation mechanisms.

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The accessibility of open-source data on fresh food supply chains provides key stakeholders from the public and private sectors with insights for better decision-making to drive food loss reduction. Nigeria has a fair amount of open-source agricultural and climate-related data. However, most of these datasets are not readily accessible. This paper presents a detailed method used to develop an interactive web Geographic Information System (GIS) tool that collates and visualizes available open-source datasets on Nigeria's Agricultural Sector with particular focus on the fresh produce supply chains. The following steps were used to create such an interactive map. •Open-source data were acquired in various forms, including tabular, vector, and rasters, processed and uploaded as layers on the interactive web map.•Most of the data needed some processing on open-source geographic information system applications and web-based computing platforms to transform them into sources of actionable insights•These final processed layers were then uploaded to a consolidated interactive web map built on the Google Earth Engine platform. The gathered open-source data includes crop production data, market prices, weather, road network, market locations, mobile coverage, water access, water scarcity, and food insecurity. The method described here also allows the reproduction of such maps for other countries.

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Sharp wave-ripple complexes (SWRs) are hippocampal network phenomena involved in memory consolidation. To date, the mechanisms underlying their occurrence remain obscure. Here, we show how the interactions between pyramidal cells, parvalbumin-positive (PV+) basket cells, and an unidentified class of anti-SWR interneurons can contribute to the initiation and termination of SWRs. Using a biophysically constrained model of a network of spiking neurons and a rate-model approximation, we demonstrate that SWRs emerge as a result of the competition between two interneuron populations and the resulting disinhibition of pyramidal cells. Our models explain how the activation of pyramidal cells or PV+ cells can trigger SWRs, as shown in vitro, and suggests that PV+ cell-mediated short-term synaptic depression influences the experimentally reported dynamics of SWR events. Furthermore, we predict that the silencing of anti-SWR interneurons can trigger SWRs. These results broaden our understanding of the microcircuits supporting the generation of memory-related network dynamics.SIGNIFICANCE STATEMENT The hippocampus is a part of the mammalian brain that is crucial for episodic memories. During periods of sleep and inactive waking, the extracellular activity of the hippocampus is dominated by sharp wave-ripple events (SWRs), which have been shown to be important for memory consolidation. The mechanisms regulating the emergence of these events are still unclear. We developed a computational model to study the emergence of SWRs and to explain the roles of different cell types in regulating them. The model accounts for several previously unexplained features of SWRs and thus advances the understanding of memory-related dynamics.

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Humans detect skin temperature changes that are perceived as warm or cool. Like humans, mice report forepaw skin warming with perceptual thresholds of less than 1°C and do not confuse warm with cool. We identify two populations of polymodal C-fibers that signal warm. Warm excites one population, whereas it suppresses the ongoing cool-driven firing of the other. In the absence of the thermosensitive TRPM2 or TRPV1 ion channels, warm perception was blunted, but not abolished. In addition, trpv1:trpa1:trpm3-/- triple-mutant mice that cannot sense noxious heat detected skin warming, albeit with reduced sensitivity. In contrast, loss or local pharmacological silencing of the cool-driven TRPM8 channel abolished the ability to detect warm. Our data are not reconcilable with a labeled line model for warm perception, with receptors firing only in response to warm stimuli, but instead support a conserved dual sensory model to unambiguously detect skin warming in vertebrates.

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ABSTRACT Introduction: Aging is inevitable and irreversible, but with the advancement of technology, life expectancy is increasing every year, bringing proposals for various interventions to improve the quality of life. One such intervention is physical exercise programs. Objectives: To investigate the impact of multicomponent training in circuits on functional autonomy parameters in elderly women. Methods: Elderly were recruited and distributed in two groups: trained (N = 16) and non-trained (N = 15). Those in the trained group performed 75-minute training sessions twice a week over a 56-week period. The resistance training included upper and lower limbs with a relative intensity of 70% of 1RM, exercises using body weight, stretching and specific tasks for agility, performed in a circuit form and totaling three passages. Participants underwent functional autonomy (FA) assessment by the protocol of the Latin American Developmental Group for Maturity, the 6-minute walk test (T6M), and the sit-and-reach (SR) test. Results: The trained group had a significant decrease in body weight (p=0.02) and body mass index (p=0.015). Significant improvements (p=0,009) were also observed in FA, SR, and T6M after the intervention Compared with the untrained group, the trained group also obtained significant differences in all functional parameters analyzed. Conclusion: A long-term multicomponent training program conducted on a circuit and applied twice a week was enough to improve multiple components of the functional autonomy of elderly women. Level of Evidence II; Prognostic studies - Investigating the effect of a patient characteristic on the outcome of disease.

RESUMO Introdução: O envelhecimento é inevitável e irreversível, porém, com o avanço da tecnologia, a expectativa de vida está aumentando a cada ano, trazendo propostas de diversas intervenções para melhorar a qualidade de vida. Entre elas, encontram-se os programas de exercício físico. Objetivos: Investigar o impacto do treinamento multicomponente realizado em circuitos sobre os parâmetros de autonomia funcional em mulheres idosas. Métodos: Idosas foram recrutadas e distribuídas em dois grupos: treinado (N = 16) e não treinado (N = 15). As idosas do grupo treinado realizaram sessões de treino de 75 minutos, duas vezes por semana, durante um período de 56 semanas. Os exercícios resistidos abrangeram membros superiores e inferiores com intensidade relativa de 70% de 1RM, exercícios usando peso corporal, alongamento e tarefas específicas para agilidade, realizados em forma de circuito e totalizando três passagens. As participantes foram submetidas à avaliação da autonomia funcional (AF) pelo protocolo do Grupo de Desenvolvimento Latino-Americano para a Maturidade, ao teste de caminhada de seis minutos (T6M) e ao teste de sentar e alcançar (SA). Resultados: O grupo treinado teve diminuição significativa do peso corporal (p = 0,02) e do índice de massa corporal (p = 0,015). Foram observadas também melhoras significativas (p = 0,009) no AF, no SA e no T6M após a intervenção. Em comparação com o grupo não treinado, o grupo treinado também obteve diferenças significativas em todos os parâmetros funcionais analisados. Conclusão: Um programa de longa duração de treinamento multicomponente realizado em circuito e aplicado duas vezes por semana foi suficiente para melhorar múltiplos componentes da autonomia funcional de idosas. Nível de Evidência II; Estudos prognósticos - Investigação do efeito de característica de um paciente sobre o desfecho da doença.

RESUMEN Introducción: El envejecimiento es inevitable e irreversible, pero con el avance de la tecnología la expectativa de vida está aumentando cada año, trayendo propuestas de diversas intervenciones para mejorar la calidad de vida. Entre ellas, se encuentran los programas de ejercicio físico. Objetivos: Investigar el impacto del entrenamiento multicomponente realizado en circuitos sobre los parámetros de autonomía funcional en mujeres ancianas. Métodos: Las ancianas fueron reclutadas y distribuidas en dos grupos: entrenado (N = 16) y no entrenado (N = 15). Las ancianas del grupo entrenado realizaron sesiones de entrenamiento de 75 minutos, dos veces por semana, durante un período de 56 semanas. Los ejercicios resistidos abarcaron miembros superiores e inferiores con intensidad relativa del 70% de 1RM, ejercicios usando el peso corporal, estiramiento y tareas específicas para agilidad, realizados en forma de circuito y totalizando tres pasajes. Las participantes fueron sometidas a la evaluación de la autonomía funcional (AF) por el protocolo del Grupo de Desarrollo Latinoamericano para la Madurez, a la prueba de caminata de seis minutos (T6M) y a la prueba de sentarse y alcanzar (SA). Resultados: El grupo entrenado tuvo una disminución significativa del peso corporal (p = 0,02) y del índice de masa corporal (p = 0,015). Se observaron también mejoras significativas (p = 0,009) en el AF, en el SA y en el T6M después de la intervención. En comparación con el grupo no entrenado, el grupo entrenado también obtuvo diferencias significativas en todos los parámetros funcionales analizados. Conclusión: Un programa de larga duración de entrenamiento multicomponente realizado en circuito y aplicado dos veces por semana fue suficiente para mejorar múltiples componentes de la autonomía funcional entre las mujeres mayores. Nivel de Evidencia II; Estudios prognósticos - Investigación del efecto de características de un paciente sobre el desenlace de la enfermedad.

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The distinctive firing pattern of grid cells in the medial entorhinal cortex (MEC) supports its role in the representation of space. It is widely believed that the hexagonal firing field of grid cells emerges from neural dynamics that depend on the local microcircuitry. However, local networks within the MEC are still not sufficiently characterized. Here, applying up to eight simultaneous whole-cell recordings in acute brain slices, we demonstrate the existence of unitary excitatory connections between principal neurons in the superficial layers of the MEC. In particular, we find prevalent feed-forward excitation from pyramidal neurons in layer III and layer II onto stellate cells in layer II, which might contribute to the generation or the inheritance of grid cell patterns.

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