31 research outputs found

    Análise da variabilidade ambiental da chuva no município de Chapada Gaúcha, Minas Gerais.

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    Os objetivos deste estudo são: i) verificar a variabilidade anual e mensal da chuva, e ii) avaliar a ocorrência do Índice de Precipitação Padronizada, nas escalas de tempo de três (SPI-3) e doze (SPI-12) meses, no município de Chapada Gaúcha, MG. Foi utilizada uma série de 26 anos (1990-2015) de dados de precipitação coletados numa propriedade rural. O SPI-3 representou os trimestres de janeiro a março, abril a junho, julho a setembro e, outubro a dezembro, e o SPI-12 representou os meses de janeiro a dezembro. A análise descritiva e exploratória da série temporal de chuva permitiram identificar a ocorrência de chuvas inferiores as medianas nos meses de janeiro e novembro, e que a estação chuvosa ocorre entre os meses de outubro a março, indicando uma baixa variabilidade temporal mensal da chuva no município. Entretanto, a utilização do índice SPI para diferentes escalas permitiu identificar que existe o predomínio da classe "próximo da normal" na distribuição trimestral (SPI-3) e anual (SPI-12). Na escala trimestral (SPI-3), considerando o período entre julho e setembro, houve o maior número de eventos da classe "extremamente seco"

    Estimativa de áreas agrícolas utilizando o produto MOD13Q1 em Baturité, Ceará.

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    Avaliou-se a dinâmica de áreas agrícolas através da classificação por árvore dedecisão entre os anos de 2000 a 2011 no município de Baturité, Estado do Ceará. Foram utilizados o produto MOD13Q1, e o Modelo Digital de Elevação (MDE) gerado a partir dos sensores de radar a bordo do ônibus espacial Endeavour, no projeto SRTM (Shuttle Radar Topography Mission) para montagem da árvore de decisão e classificação das áreas agrícolas de Baturité. O teste Qui-quadrado revelou que o 2 cal χ (1967,93) é superior ao 2 0 χ (19,68) para o intervalo de confiança de α = 5% e 9 graus de liberdade, consequentemente aceita-se a hipótese de nulidade que afirma que os dados observados não são diferentes dos dados estimados. Os resultados obtidos mostram que a técnica da árvore de decisão foi eficaz na determinação das áreas agrícolas em Baturité. A ferramenta poderá dar suporte para levantamentos e planejamentos para tomada de decisões no setor primário (agricultura/pecuária) dos municípios do Ceará

    Desafios para a mitigação da emissão de metano entérico no Semiárido brasileiro.

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    Metano; Produção de metano.bitstream/item/211703/1/Desafios-para-a-mitigacao-da-emissao-de-metano-enterico-no-Semiarido-brasileiro.pd

    Fermentation dynamics, nutritional quality, and heating capacity of mixed silages of elephant grass (Pennisetum purpureum Schum) and Leucaena (Leucaena leucocephala).

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    Leucaena has been used to make mixed silages to obtain nutritional enrichment of the silages. Thus, the inclusion of Leucaena as an additive in mixed elephant grass silages can reduce fermentation losses, and increase the nutritional value and aerobic stability of the mixed silage without changing the fermentation profile. This study evaluated the fermentation profile, nutritional composition, and aerobic stability of elephant grass silages combined with different levels of Leucaena. A total of five inclusion levels of Leucaena (0, 20, 40, 60, and 80% on a dry matter basis) were added to elephant grass silages. A completely randomized design was adopted, with 5 treatments and 3 repetitions, totaling 15 experimental silos that were opened after 30 days of sealing. Fermentation profile, chemical composition, and aerobic stability were analyzed. A descriptive analysis of temperature and pH peaks during aerobic stability was performed. The increase in the inclusion of Leucaena in the composition of silages reduced gas and effluent losses, neutral and acid detergent fiber, cellulose, lignin, total and fiber carbohydrates, and total digestible nutrients, and resulted in increased dry matter, ether extract, and crude protein. A quadratic effect of treatments was found for the temperature to reach the maximum pH (P=0.009). Aerobic stability remained constant after 40% Leucaena inclusion in the composition of elephant grass silages. The inclusion of Leucaena up to 80% in the composition of elephant grass silages reduces fermentation losses, promotes a nutritional increase, and increases the aerobic stability of the silages

    Meat quality in ewes submitted to reduction in water supply.

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    The aim of this study was to evaluate the reduction in water supply (ad libitum intake - 100%, or 80%, 60% and 40% of ad libitum intake) on the proximate composition, physicochemical properties, mineral composition and fatty acid profile of ewe meat. Thirty-two crossbred Santa In?es ewe (n = 8 per treatment) were distributed in a randomized block design, receiving a diet consisting of elephant grass and concentrate (70:30). The experimental period lasted 63 days, preceded by 14 days of adaptation. Ewes were slaughtered at the end of experimental period, at a mean final body weight of 37.63 kg. Carcasses were cut lengthwise and the loin (longissimus lumborum) was taken of the left half carcass to evaluate the proximate composition, the physicochemical characteristics, the minerals content and fatty acid profile. The reduction in water supply resulted in a quadratic effect for resilience (p < 0.05), Lightness L* (p < 0.05), potassium (p < 0.05) and iron content (p < 0.001). There was a decreasing linear effect for magnesium content (p < 0.05), copper content (p < 0.001), C18:1n7t content (p < 0.05) and &#931;monounsaturated content (p < 0.05). Crossbred Santa In?es ewe tolerate water restriction up to 40% voluntary intake without compromising the meat quality

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure &lt;= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt
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