753 resultados para Clayton Copula
Resumo:
1992
Resumo:
1986
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A tecnica do Inseto Esteril (SIT) e um tipo de controle especifico e nao poluente de pragas tem sido ja utilizado com sucesso por alguns paises. A Broca da cana-de-acucar, D. saccharolla (F.), e um dos insetos candidatos ao controle por meio desta tecnica. No presente trabalho procurou-se estabelecer a dose de radiacao gama, que aplicada na fase pupal, torna os machos adultos estereis. utilizou-se crisalidas com idade de 5 a 7 dias, as quais foram irradiadas com doses de 3, 5, 7, e 9 Krad, mais a testemunha. Foram irradiados sob uma taxa de 35 Krad/hora. A medida que os machos emergiam dos pulparios, eram colocados junto com femeas normais para acasalamento. Atraves da contagem dos ovos ferteis, obteve-se 45%, 56%, 24%, 4% e 16% de fertilidade, respectivamentepara as doses de 0,3, 5, 7 e 9 Krad. O numero medio dos ovos por femea foi respectivamente de 69, 97, 100, 83, e 37. Pelos resultados nota-se que a dose de 7 Krad foi a que proporcionou maior esterelidade. O que esperava e que a porcentagem de fertilidade fosse inversamente proporcional as doses de radiacao, mas tal nao ocorreu pois a de Krad apresentou uma fertilidade maior em relacao a dose de 7 Krad. Em compensacao o numero de ovos por femea decresceu em funcao do aumento da dose de radiacao empregada.
Resumo:
The current study investigated the effects of the supplementation of lambs with algae on the expression of genes that direct the accumulation of long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA). The nutrition of the lamb's dam around mating was also considered. The dams were fed with either silage (SLG) or oat/cottonseed (OAT) based diets for six weeks prior to and, three weeks following conception. mRNA levels of FADS1, FADS2, CPT1, SCD, ACC and fad2 were measured in the liver, muscle and subcutaneous fat from lambs fed a control diet consisting of oat and lupin grains and chopped lucerne (CTRL) or the CTRL diet with algae (DHAgold™) added at 1.92% DM (ALG). The lambs were 117.4±2.4 days of age and weighed 37.3±3.2 kg at the beginning of the experimental period, and six weeks later they were slaughtered at 160.4±2.4 days of age and a final live weight of 50.1±4.4 kg. The expression of FADS1 in liver tissue was not affected (P>0.05) by the interaction between dam nutrition and algae supplementation, however it was higher (P<0.05) when lambs received the ALG diet compared with the CTRL and when their dams were fed SLG compared with OAT diet. The expression of FADS1 in muscle was negatively correlated (P<0.05) with the concentration of 20:4n-6, 20:5n-3 and 22:4n-6. The expression of FADS1, FADS2, SCD and ACC genes in lamb muscle was differentially affected by dam nutrition with the highest levels for the SLG+ALG treatment (P<0.05) compared with other treatments. The expression of SCD gene was not affected (P>0.05) by algae supplementation, but it was higher (P<0.05) when dams were fed SLG compared with OAT, however ACC was not affected (P>0.05).
Resumo:
Tall buildings are wind-sensitive structures and could experience high wind-induced effects. Aerodynamic boundary layer wind tunnel testing has been the most commonly used method for estimating wind effects on tall buildings. Design wind effects on tall buildings are estimated through analytical processing of the data obtained from aerodynamic wind tunnel tests. Even though it is widely agreed that the data obtained from wind tunnel testing is fairly reliable the post-test analytical procedures are still argued to have remarkable uncertainties. This research work attempted to assess the uncertainties occurring at different stages of the post-test analytical procedures in detail and suggest improved techniques for reducing the uncertainties. Results of the study showed that traditionally used simplifying approximations, particularly in the frequency domain approach, could cause significant uncertainties in estimating aerodynamic wind-induced responses. Based on identified shortcomings, a more accurate dual aerodynamic data analysis framework which works in the frequency and time domains was developed. The comprehensive analysis framework allows estimating modal, resultant and peak values of various wind-induced responses of a tall building more accurately. Estimating design wind effects on tall buildings also requires synthesizing the wind tunnel data with local climatological data of the study site. A novel copula based approach was developed for accurately synthesizing aerodynamic and climatological data up on investigating the causes of significant uncertainties in currently used synthesizing techniques. Improvement of the new approach over the existing techniques was also illustrated with a case study on a 50 story building. At last, a practical dynamic optimization approach was suggested for tuning structural properties of tall buildings towards attaining optimum performance against wind loads with less number of design iterations.
Resumo:
Introducción Las pacientes con miomas uterinos pueden llegar a sufrir de síntomas urinarios y de disfunción sexual. Es para nosotros importante conocer la frecuencia de estas patologías en pacientes con miomas con indicación de cirugía atendidos en el Hospital Universitario Mayor Méderi y la relación entre estas tres entidades. Metodología Estudio cuasi experimental de antes-después. El estudio se encuentra dividido en dos fases, en esta primera fase a las pacientes se les aplicó los cuestionarios FSFI, IIQ-7 y UDI-6 antes de realizar el procedimiento quirúrgico. En una segunda fase se realizará un nuevo abordaje a los 6 y 12 meses donde se aplicarán los mismos instrumentos. Se utilizó coeficiente de Spearman y Kruskall-Wallis para evaluar la relación. Resultados En esta primera fase se incluyeron 81 participantes, con una mediana de años de 46 (RIQ=42-49) mínimo 33 y máximo 71 años. La mediana de miomas fue de 1 (RIQ1-2) máximo 5 miomas. El resultado total de la FSFI fue de 21(RIQ=18,5-25,5). La mediana de la escala UDI -6 fue de 50,4 (RIQ=0-31,2) y la mediana de IIQ-7 fue de 4,75 (RIQ=0-23,7). Se presentó una correlación negativa débil entre los puntajes de FSFI y los cuestionarios UDI-6 (-0.3604) e IIQ 7 (-0.3530), con una prevalencia de riesgo de disfunción sexual de 61%. Conclusiones En esta primera fase de la investigación se pudo observar una existencia de correlación entre la función sexual y la sintomatología urinaria. La prevalencia de disfunción sexual es mayor que en población de mujeres sin patología de miomas uterino.
Resumo:
La investigación busca determinar el propósito que persiguen los pequeños Estados insulares en desarrollo del Pacífico al adoptar una trayectoria de desarrollo sostenible. Se plantea que la adopción de una trayectoria de desarrollo sostenible es la estrategia por medio de la cual estos Estados buscan hacer frente a su condición de vulnerabilidad; lo cual logran a través del uso de la diplomacia en distintos escenarios multilaterales, con el fin de modificar tanto sus prácticas como las de otros actores.
Resumo:
1987
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The process of modernization of Brazilian agriculture aimed at increasing the productivity in response to the high demand for agricultural products in the world market and it was based on the intensive use of inputs such as agrochemicals, intense mechanisation and breeding of new varieties. Among these, pesticides were incorporated in almost all production systems. Over reliance on pesticide use has produced many negative effects on both biotic and abiotic components of the environment, generating chemical contamination of soil and water, decrease in biological diversity of agroecosystems, disruption of natural cycles, pest resistance, intoxication of growers, among others. The consumption of pesticides in Brazil was 151.8 thousand tonnes in 1989, and today the country is the fifth world market of these products. The use of pesticides increased from 16 thousand tonnes (a.i.) in 1964 to 60.2 thousand tonnes in 1991, while the area planted to crops grew from 28.4 to 50.0 million ha in the same period. This means an increase of 276.2% in consumption of pesticides compared to an increase of 76% in planted area. Even with this large increase in the use of pesticides, the losses caused by pests have not been significantly reduced, and the net gain in crop productivity has been low. On the other hand, problems with food contamination, environmental degradation of growers have considerably mounted. It is possible to define two classes of crops regarding intense use of pesticides. One is represented by those crops that occupy large areas, and therefore contribute to a large amont of pesticides used for pest control in a country basis. The other class comprises crops that require large amounts of pesticides per unit of area, but not necessarily represent large amounts of pesticides used coutry-wide. Based on the classes proposed, citrus, soybean and sugarcane stand as crops with a nationally great consumption of pesticides, while tomato, potato and citrus are important as intensive users of pesticides. In this paper the biotechnologies in use, the biotechnologies in advanced stages of development, the main constraints to the development and use of biotechnlology and the impact of pesticed on the environment are discussed.
Resumo:
1988
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A field efficacy evaluation revealed significant differences in efficacy among a few of the numerous insecticides or combinations of insecticides applied for Heliothis spp. control. An increasing proportion of made up this field population during the test period. Partial budgeting revealed that the net returns from applying any treatment were directly proportional to the resulting yield obtained from that treatment.
Resumo:
1988
Resumo:
Como a diapausa manifestada nos bicudos e um importante mecanismo de sua sobrevivencia nos Estados Unidos durante a entressafra, e fundamental que se conhecam detalhes de sua ocorrencia no Brasil, a fim de se introduzirem tecnicas eficientes de manejo dessa especie. Com o presente trabalho objetivou-se verificar a incidencia da diapausa em lavouras de algodao de alguns municipios do Estado de Sao Paulo. Na safra 1983/84 o estudo desenvolveu-se em 10 municipios e em 1984/85, em 7 municipios. O numero de adultos coletados, bem como o numero de coletas realizadas em cada tempo, foram variaveis. Em praticamente todas as coletas ocorreram adultos em diapausa, excetuando-se as de 18/04/84 e 15/02/85 para Porto Feliz e a de 10/05/1985 para Tiete. As maiores porcentagens de bicudos em diapausa foram observadas nos meses de marco a abril, fase final do ciclo das plantas. Na safra 1984/85 altas porcentagens ocorreram tambem em maio, mas na safra 1983/84 nao foram conduzidas coletas nessa epoca. Os maiores indices de diapausa foram observados em Monte Mor, no periodo de 19-23/03/84, com cerca de 54% e em Campinas, no periodo de 12-18/03/85, com cerca de 56%.
Resumo:
A abordagem do tema será feita enfocando-se dois aspectos relevantes. O primeiro refere-se ao modelo de desenvolvimento econômico, ou seja, a questão do paradigma existente relacionada diretamente à questão do meio ambiente. O segundo irá tratar da questão da agricultura e meio ambiente. Neste tema serão discutidos os entraves e desafios para a gestão ambiental da agricultura, bem como os pontos mais importantes que possibilitem o repensar da agricultura para o seu direcionamento rumo à sustentabilidade. Por fim, serão comentadas as principais tendências na agricultura e meio ambiente, com suas diversificadas repercussões.
Resumo:
1986