2,012 research outputs found

    Uso de óleos essenciais de cravo-da-índia, melaleuca, eucalipto e menta na sedação de peixe.

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    Com objetivo de avaliar o efeito no comportamento, tempo para sedação e tempo para recuperação de soluções preparadas com óleos essenciais extraídos de quatro tipos vegetais, com a finalidade de reduzir estresse dos peixes.Organizado por: Sílvio Ricardo Maurano; AQUACIÊNCIA 2012

    Comportamento de lagartas de Spodopetra frugiperda (Lepidoptera, Noctuidae) parasitadas por chelonus insularis (Hymenoptera, Braconidae), sobre plantas de milho.

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    This research was conducted in greenhouse at the National Corn and Sorghum research center of Embrapa in Sete Lagoas, MG, Brasil. It aimed to study the general behavior of Spodoptera frugiperda lervae attacked by the egg-larval parasitoid Chelonus Insularis. Fourteen parasitized and fourteen non-parasitized 3 days old host larvae evaluated using a visual scale form zero to five. On 6th observation day plant corn leaf, regardless of being parasitized. Healthy larvae presented high mobility and caused higher damage on the plants than parasitized larvae which pupate earlier

    Aspectos biológicos do parasitoide Chelonus insularis (Cresson) (Hymenoptera, braconidae) criados em ovos de Spodoptera frugiperda, noctuidae).

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    Biological aspects of the parasitoid Chelonus insularis (Cresson) (Hymenoptera, braconidae) reared on eggs of Spodoptera frugiperda(Smith) (Lepidoptera, braconidae). Biological aspects of Chelonus insularis (Cresson, 1865) an egg-larval parasitoid reared on Spodoptera frugiperda (Smith, 1797) eggs helonus insularis (Cresson, 1865) has been cited in the international literature as a promissing biological control agent against the fall armyworm. Spodoptera frugiperda (Smith, 1797). Its field occurrence in Sete Lagoas, Minas Gerais (Brasil) has been increasing in the last years. For these reasons this experiment was conducted in the laboratory, at the National Corn and Sorghum Research Center, of EMBRAPA, under temperature of 25oC, RH of 73% and phophate of 12 hours. Ten couples of the parasitoid were individually placed in a glass jar (5 liters capacity). They were fed on a 10% sugar solution. Each couple received one fall armyworm egg mass to oviposit during a 24 hour period. After hatching, the larvae were fed on artificial bean diet, up to the death caused by the parasitoid larvae. The total biological life cycle was 26,61 days on the average (larval period of 20,42 and pupal period of 6.19 days). The average weight of two days - old pupae was 0.02g. The adult longevity was on average, 10 days (8,4 days for males and 11.6 days for females). The greatest rate of parasitism occurred when the female was three days old, with a maximum of 92 eggs parasitized in that day

    STOCHASTIC OPTIMIZATION OF MULTIPLEX CHARGES BASED ON INTERIOR BALLISTICS SIMULATIONS

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    Multiplex charges combine propellant grains with regressive, neutral and progressive burning behaviors in a single propellant charge to improve the interior ballistics. This work optimizes the mass and the web thickness of each type of propellant grain used in a multiplex charge. Two optimization problems are studied: the maximization of the muzzle velocity and the minimization of the maximum pressure inside the gun. Particle Swarm Optimization (PSO) and Differential Evolution (DE) were used to solve the optimization problems. The interior ballistics of a 155 mm howitzer was simulated by using a lumped parameters model. In this model, the lost energy and the resistance pressure are defined by spline functions based on reference data. The results show that optimized multiplex charges can be used to increase the weapon’s utility range and to reduce the weapon’s weight

    Levantamento fitossociológico de plantas daninhas em sorgo sacarino semeado em diferentes espaçamentos e densidades.

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    Edição dos Resumos do 1º Seminário de Agroecologia da América do Sul, 5º Seminário de Agroecologia de Mato Grosso do Sul, 4º Encontro de Produtores Agroecológicos de Mato Grosso do Sul, 1º Seminário de Sistemas Agroflorestais em Bases Agroecológicas de Mato Grosso do Sul, Dourados, nov. 2014

    Comportamento de corte, acasalamento e postura de Chelonus insularis (Hymenoptera: Braconidae) em ovos de Spodoptera frugiperda.

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    Procurou-se descrever, em laboratorio, o comportamento de corte, acasalamento e postura de C.insularis tendo S.frugiperda como hospedeiro. Dez casais de tres dias de idade foram individualizados em copos plasticos de 50ml de capacidade e observados para a descricao do comportamento. Verificou-se o inicio da sequencia de corte quando o macho toca suas antenas em qualquer parte do corpo da femea. A partir dai, movimenta suas antenas com grande frequencia, bate asas, desloca-se rapidamente e assume a posicao de copula, que consiste na sua monta sobre a femea. Esta permanece em posicao normal de caminhamento, porem sem se mover. (Femeas receptivas apresentaram poucos batimentos de asas e antenas. Em 20% das observacoes, a cabeca do macho ficava em posicao oposta a da femea). A duracao media da copula foi de 20 segundos, (com uma amplitude de 2 a 60 segundos). No comportamento de postura as femeas, diante da massa de ovos a serem parasitados, iniciaram imediatamente os batimentos de antenas tentando se orientar e em seguida iniciaram a oviposicao, que durou de 2 a 12 segundos. A intensidade de postura diminuiu apos 30 minutos de contato da femea com a massa de ovos

    Reconsidering mammal extinctions in the Pernambuco Endemism Center of the Brazilian Atlantic Forest

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    Reconsiderando la extinción de mamíferos en el Centro de Endemismo Pernambuco perteneciente al bosque atlántico brasileño Se ha calculado que, en los últimos 500 años, se han extinguido 21 mamíferos en el Centro de Endemismo Pernambuco. En el presente estudio, realizamos un examen crítico de los datos aportados en las publicaciones científicas históricas y recientes, y concluimos que el número real de mamíferos extintos es de siete, lo que indica que la cifra anterior de 21 especies extintas es una sobrestimación de aproximadamente 30 %. Nuestra lista difiere de las publicaciones previas en que incluye especies aún existentes (n = 5) y excluye otras que nunca habían sido registradas en el Centro de Endemismo Pernambuco (n = 8). Asimismo, señalamos que, al elaborar listas de fauna extinta a escala regional, es necesario adoptar un planteamiento más riguroso en relación con los registros históricos y recientes, dado que las identificaciones erróneas y las suposiciones falsas podrían conducir a la pérdida de credibilidad ante las partes interesadas y, en última instancia, ser negativas para la conservación de especies.In the last 500 years, there have been an estimated 21 mammal extinctions in the Pernambuco Endemism Center. We critically reviewed the published historical and recent literature records and concluded that the actual number of mammal species extinction was seven, indicating that the previous figure of 21 species lost is an overestimation of approximately 30 %. Our checklist differs from previous publications by including species that are still extant (n = 5), and removing species that have never been recorded in the Pernambuco Endemism Center (n = 8). We point out that a more rigorous approach towards historical and recent records is needed when producing lists of regionally extinct fauna, given that the implications of misidentifications and false assumptions can potentially lead to loss of credibility by stakeholders and ultimately have a negative effect on species conservation.Reconsiderando la extinción de mamíferos en el Centro de Endemismo Pernambuco perteneciente al bosque atlántico brasileño Se ha calculado que, en los últimos 500 años, se han extinguido 21 mamíferos en el Centro de Endemismo Pernambuco. En el presente estudio, realizamos un examen crítico de los datos aportados en las publicaciones científicas históricas y recientes, y concluimos que el número real de mamíferos extintos es de siete, lo que indica que la cifra anterior de 21 especies extintas es una sobrestimación de aproximadamente 30 %. Nuestra lista difiere de las publicaciones previas en que incluye especies aún existentes (n = 5) y excluye otras que nunca habían sido registradas en el Centro de Endemismo Pernambuco (n = 8). Asimismo, señalamos que, al elaborar listas de fauna extinta a escala regional, es necesario adoptar un planteamiento más riguroso en relación con los registros históricos y recientes, dado que las identificaciones erróneas y las suposiciones falsas podrían conducir a la pérdida de credibilidad ante las partes interesadas y, en última instancia, ser negativas para la conservación de especies

    Sucrose in detoxification of coffee plants with glyphosate drift.

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    The weed control in coffee plants has great importance, as they compete for light, water and nutrients. The chemical control is the most used, emphasizing the glyphosate, however, when applied, drift can occur and consequently cause injuries to coffee. Many farmers use the sucrose application with the objective to reverse the damage caused by the herbicide drift, even without scientific basis to justify such action. The objective of this study was to evaluate the effect of the sucrose application on the detoxification of coffee plants in the implantation phase with glyphosate drift. The experiment was carried out in a greenhouse, using a randomized block design, arranged in a 3 x 3 factorial scheme with 2 additional treatments, using 3 sucrose doses (2, 4 and 8%) with 3 application times (1, 24 and 168 hours after intoxication with 10% of the commercial glyphosate dose) with an additional one in which the plants were not intoxicated and not treated with sucrose and another only with plants intoxicated by glyphosate. After 75 days performing the experiment, growth, physiological and anatomical characteristics were evaluated. The application of sucrose in the reversal of intoxication of growth variables (height, leaf area number of leaves, shoot dry weight and dry weight of the root system) was not efficient. The objective of this study was to evaluate the effect of the sucrose application on the detoxification of coffee plants in the implantation phase with glyphosate drift. For the physiological variables the application of 2% sucrose, one hour after glyphosate intoxication was the most efficient treatment
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