26 research outputs found
Sugarcane Industry Development Analysis from the Perspective of Agro-Industrial System Quantification
Sugarcane sector has a strong impact as a wealth generator for Brazil. Several authors discuss the importance of quantifying an agro-industrial system. This article aims to analyze the development of the Brazilian sugarcane sector over the past five years and to assess whether the method of mapping and quantification of agribusiness systems (GESis) is a useful tool for analyzing the economic development of an agro-industrial system. The application of the method enabled to see the performance of all the links that make up the agro-industrial system. It also proved to be an important tool to analyze the performance of an agro-industrial system, pointing possible areas for improvement and opportunities. The comparison between both studies contributes to both a better visualization of the sugarcane sector evolution and a better understanding of situational reality of the sector
Carbono (C), Nitrogênio (N) e relação C/N em raízes, tronco, galhos, folhas e frutos de laranjeiras (Citrus sinensis L. Osbeck) no estado de São Paulo.
RESUMO: Subsidiar a citricultura com informações sobre carbono (C) e nitrogênio (N) em laranjeiras pode favorecer o estabelecimento de iniciativas que visem a mitigação das mudanças climáticas, bem como o manejo e a renovação dos pomares. Este estudo teve como objetivo avaliar o conteúdo de C e N e a relação C/N em raízes, tronco, galhos, folhas e frutos de laranjeiras representativas do cinturão citrícola de São Paulo, Triângulo Mineiro e Sudoeste de Minas Gerais. Dezesseis laranjeiras foram avaliadas pelo método destrutivo, e as amostras foram analisadas em analisador elementar de C e N. Galhos (44,98%), raízes (44,67%) e tronco (44,66%) apresentaram maior conteúdo de C quando comparados a folhas (43,01%) e frutos (39,77%). Ao considerar a média ponderada da biomassa de raízes, tronco, galhos e folhas das laranjeiras avaliadas, o conteúdo de C chegou à média de 44,69%. Quanto ao N, as folhas foram o compartimento com maior conteúdo (2,34%), seguidas por frutos (0,86%), raízes (0,29%), galhos (0,20%) e tronco (0,17%). A relação C/N mais próxima foi observada nas folhas, com 18 partes de C para uma de N, que é estatisticamente semelhante aos frutos, que apresentaram relação de 46/1. Essas informações podem contribuir para estabelecer práticas de manejo de biomassa que aumentem os estoques de C e N no solo, bem como melhorem a relação C/N. Também podem contribuir com estimativas de estoque de carbono em projetos que visam à redução de emissões de gases de efeito estufa ou ao aumento do sequestro de carbono.CIIC 2023. Nº 23506
Abundância de gavião-real e gavião-real falso numa área sob impacto de reservatório no Baixo e Médio rio Xingu
In the Brazilian Amazon, two monospecific genera, the Harpy Eagle and Crested Eagle have low densities and are classified by IUCN as Near Threatened due to habitat loss, deforestation, habitat degradation and hunting. In this study, we evaluate occurrence of these large raptors using the environmental surveys database from Belo Monte Hydroelectric Power Plant. Integrating the dataset from two methods, we plotted a distribution map along the Xingu River, including records over a 276-km stretch of river. Terrestrial surveys (RAPELD method) were more efficient for detecting large raptors than standardized aquatic surveys, although the latter were complementary in areas without modules. About 53% of the records were obtained during activities of wildlife rescue/flushing, vegetation suppression or in transit. Between 2012 and 2014, four Harpy Eagles were removed from the wild; two shooting victims, one injured by collision with power lines and one hit by a vehicle. Also, seven nests were mapped. The mean distance between Harpy Eagle records was 15 km along the river channel, with a mean of 20 km between nests near the channel, which allowed us to estimate 20 possible pairs using the alluvial forest, riverine forest and forest fragments. Territories of another ten pairs will probably be affected by inundation of the Volta Grande channel, which is far from the main river. The average distance between Crested Eagle records was 16 km along the river channel. The only nest found was 1.3 km away from a Harpy Eagle nest. The remnant forests are under threat of being replaced by cattle pastures, so we recommend that permanently protected riparian vegetation borders (APP) be guaranteed, and that forest fragments within 5 km of the river be conserved to maintain eagle populations. © 2015, Instituto Internacional de Ecologia. All rights reserved
Development of a Digital Rock Physics workflow for the analysis of sandstones and tight rocks
Seizure-like discharges induced by 4-aminopyridine in the olfactory system of the in vitro isolated guinea pig brain
PURPOSE:
The study of the interactions leading to network- or region-specific propagation of seizures is crucial to understand ictogenesis. We have recently found that systemic (arterial) application of the potassium channel blocker, 4-aminopyridine (4AP), induces different and independent seizure activities in olfactory and in limbic structures. Here, we have characterized the network and cellular features that support 4AP-induced seizure-like events in the olfactory cortex.
METHODS:
Simultaneous extracellular recordings were performed from the piriform cortex, the entorhinal cortex, the olfactory tubercle, and the amygdala of the in vitro isolated guinea pig brain preparation. Intracellular, sharp electrode recordings were obtained from neurons of different layers of the region of ictal onset, the piriform cortex. Seizure-like discharges were induced by both arterial perfusion and local intracortical injections of 4AP.
KEY FINDINGS:
Arterial application of 4AP induces independent seizure activities in limbic and olfactory cortices. Both local applications of 4AP and cortico-cortical disconnections demonstrated that region-specific seizure-like events initiated in the primary olfactory cortex and propagate to anatomically related areas. Seizures induced by arterial administration of 4-AP are preceded by runs of fast activity at circa 30-40 Hz and are independently generated in the hemispheres. Simultaneous extracellular and intracellular recordings in the piriform cortex revealed that the onset of seizure correlates with (1) a gradual amplitude increase of fast activity runs, (2) a large intracellular depolarization with action potential firing of superficial layer neurons, and (3) no firing in a subpopulation of deep layers neurons. During the ictal event, neuronal firing was abolished for 10-30 s in all neurons and gradually restored and synchronized before seizure termination.
SIGNIFICANCE:
Our data show that olfactory neuronal networks sustain the generation of seizure-like activities that are independent from those observed in adjacent and connected limbic cortex regions. The data support the concept that functionally and anatomically hard-wired networks generate region-specific seizure patterns that could be substrates for system epilepsy
Low Obstacle Avoidance for Lower Limb Exoskeletons
Powered lower limb exoskeletons (LLEs) are innovative wearable robots that allow independent walking in people with severe gait impairments. Despite the recent advancements, the use of this promising technology is still restricted to clinical settings; uptake in real-life conditions as a device to promote user independence is still lacking due to the difficulty of controlling these devices in unstructured and complex environments. In this work, we propose a vision-assisted method for low obstacle avoidance to enhance the autonomy of LLEs. The exoskeleton collects information from the surroundings through a RGB-D camera to recognize and segment objects on the ground that might affect the walking pattern. Then, the method identifies suitable foothold positions. In addition, a novel iterative gait trajectory generator is proposed to automatically compute collision-free walking paths. We believe that re-thinking exoskeletons as semi-autonomous agents will represent not only the cornerstone to promote a more symbiotic human-exoskeleton interaction but may also pave the way for the use of this technology in the everyday life