Molecular identification of member species of Aspergillus section flavi contaminating brazilnut material from Acre and Amazonas.

Identificaçao molecular de especies membros do Aspergillus seçao flavi contaminantes de castanha do brasil nos estados de Acre e Amazonas

Can local vibration alter the contribution of persistent inward currents to human motoneuron firing?

Abstract: The response of spinal motoneurons to synaptic input greatly depends on the activation of persistent inward currents (PICs), which in turn are enhanced by the neuromodulators serotonin and noradrenaline. Local vibration (LV) induces excitatory Ia input onto motoneurons and may alter neuromodulatory inputs. Therefore, we investigated whether LV influences the contribution of PICs to motoneuron firing. This was assessed in voluntary contractions with concurrent, ongoing LV, as well as after a bout of prolonged LV. High-density surface electromyograms (HD-EMG) of the tibialis anterior were recorded with a 64-electrode matrix. Twenty males performed isometric, triangular, dorsiflexion contractions to 20% and 50% of maximal torque at baseline, during LV of the tibialis anterior muscle, and after 30-min of LV. HD-EMG signals were decomposed, and motor units tracked across time points to estimate PICs through a paired motor unit analysis, which quantifies motor unit recruitment–derecruitment hysteresis (ΔF). During ongoing LV, ΔF was lower for both 20% and 50% ramps. Although significant changes in ΔF were not observed after prolonged LV, a differential effect across the motoneuron pool was observed. This study demonstrates that PICs can be non-pharmacologically modulated by LV. Given that LV leads to reflexive motor unit activation, it is postulated that lower PIC contribution to motoneuron firing during ongoing LV results from decreased neuromodulatory inputs associated with lower descending corticospinal drive. A differential effect in motoneurons of different recruitment thresholds after prolonged LV is provocative, challenging the interpretation of previous observations and motivating future investigations. (Figure presented.). Key points: Neuromodulatory inputs from the brainstem influence motoneuron intrinsic excitability through activation of persistent inward currents (PICs). PICs make motoneurons more responsive to excitatory input. We demonstrate that vibration applied on the muscle modulates the contribution of PICs to motoneuron firing, as observed through analysis of the firing of single motor units. The effects of PICs on motoneuron firing were lower when vibration was concurrently applied during voluntary ramp contractions, likely due to lower levels of neuromodulation. Additionally, prolonged exposure to vibration led to differential effects of lower- vs. higher-threshold motor units on PICs, with lower-threshold motor units tending to present an increased and higher-threshold motor units a decreased contribution of PICs to motoneuron firing. These results demonstrate that muscle vibration has the potential to influence the effects of neuromodulation on motoneuron firing. The potential of using vibration as a non-pharmacological neuromodulatory intervention should be further investigated

Produção e acúmulo de biomassa de forragem de capim-tanzânia (Panicum maximum cv. Tanzânia) pelo método da morfogênese em diferentes intensidades de manejo.

Resumo: Este experimento foi conduzido para avaliar através do método da morfogênese a produtividade do capim tanzânia (Panicum maximum cv, Tanzânia) manejado sob lotação rotativa com diferentes estratégias de manejo. Sendo os manejos: intensivo (600 kg ha-1 de N ano e resíduo de 30 cm), moderado (300 kg ha-1 de N ano e resíduo de 45 cm), leve (sem adubação e resíduo de 45 cm) e extensivo (sem adubação e resíduo de 30 cm). Utilizou-se um delineamento inteiramente casualizado, com medidas repetidas no tempo, com quatro repetições por manejo. As seguintes variáveis foram analisadas: Taxa de produção total de forragem (TPF) e acúmulo líquido de forragem (TAF). Houve efeito de tratamento para as variáveis estudadas. Tanto a TPF como TAF foram maiores no ciclo um do manejo intensivo (P<0,05). A TPF 177,79 Kg MS/há x dia e a TAF (165,87 Kg MS/ha x dia). O efeito da adubação nitrogenada maximiza o fluxo de e consequentemente, a produção e acúmulo de forragem, proporcionando informações importantes para o manejo de pastagem, esse efeito pode ser observado nos tratamentos onde houve a aplicação de nitrogênio. [Production and biomass accumulation of forage grass - Tanzania (Panicum maximum cv. Tanzania) by the method of morphogenesis in different intensities of management]. Abstract: nitrogen fertilization, net herbage accumulation, net production of forage Keywords: This experiment was conducted to evaluate the method by Morphogenesis productivity Tanzania grass (Panicum maximum cv, Tanzania) managed under rotational stocking with different management strategies. Being managements: intensive (600 kg N ha-1 year and residue 30 cm), moderate (300 kg N ha-1 year and residue 45 cm), lightweight (without fertilizer and residue 45 cm) and extensive (without fertilizer and residue 30 cm). We used a completely randomized design with repeated measures, with four replicates per management. The following variables were analyzed: Rate of total forage production (TPF) and net herbage accumulation (TAF). Treatment effects for the variables studied. Both the TAF and TPP were higher in one cycle management (P<0.05). TPF 177.79 kg MS / ha x day and TAF (165.87 kg MS / ha x day). The effect of nitrogen fertilization maximizes flow and hence the production and accumulation of forage, providing important information for the management of grazing, this effect can be observed in treatments where there was nitrogen application

Efeito da taxa de lotação sobre a densidade do solo em pastagem de capim-tifton 85 (Cynodon spp.).

Taxas de lotação menores em capim-tifton 85, manejado sob lotação rotativa, favorecem a diminuição da densidade aparente do solo, melhorando as características físicas desse, auxiliando na infiltração de água no solo, desenvolvimento radicular e consequentemente, melhoria na eficiência produtiva do pasto

Morfogênese de capim-tanzânia (Panicum maximum cv. Tanzânia) em diferentes condições de manejo em pasto cultivado e irrigado.

Objetivou-se analisar o impacto da intensificação do uso do pasto, através de diferentes tipos de manejos, sobre características morfogênicas do Panicum maximum cv. Tanzânia