994 resultados para 164-995


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Blazars are active galaxies with a jet closely oriented to our line of sight. They are powerful, variable emitters from radio to gamma-ray wavelengths. Although the general picture of synchrotron emission at low energies and inverse Compton at high energies is well established, important aspects of blazars are not well understood. In particular, the location of the gamma-ray emission region is not clearly established, with some theories favoring a location close to the central engine, while others place it at parsec scales in the radio jet.

We developed a program to locate the gamma-ray emission site in blazars, through the study of correlated variations between their gamma-ray and radio-wave emission. Correlated variations are expected when there is a relation between emission processes at both bands, while delays tell us about the relative location of their energy generation zones. Monitoring at 15 GHz using the Owens Valley Radio Observatory 40 meter telescope started in mid-2007. The program monitors 1593 blazars twice per week, including all blazars detected by the Fermi Gamma-ray Space Telescope (Fermi) north of -20 degrees declination. This program complements the continuous monitoring of gamma-rays by Fermi.

Three year long gamma-ray light curves for bright Fermi blazars are cross-correlated with four years of radio monitoring. The significance of cross-correlation peaks is investigated using simulations that account for the uneven sampling and noise properties of the light curves, which are modeled as red-noise processes with a simple power-law power spectral density. We found that out of 86 sources with high quality data, only three show significant correlations (AO 0235+164, B2 2308+34 and PKS 1502+106). Additionally, we find a significant correlation for Mrk 421 when including the strong gamma-ray/radio flare of late 2012. In all four cases radio variations lag gamma-ray variations, suggesting that the gamma-ray emission originates upstream of the radio emission. For PKS 1502+106 we locate the gamma-ray emission site parsecs away from the central engine, thus disfavoring the model of Blandford and Levinson (1995), while other cases are inconclusive. These findings show that continuous monitoring over long time periods is required to understand the cross-correlation between gamma-ray and radio-wave variability in most blazars.

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Der Beifang an kleinen Fischen beim Fang von Tiefseegarnelen (Pandalus borealis) ist sowohl aus Gründen des Bestandsschutzes als auch aus der Sicht des Fischers absolut unerwünscht. Diese Fische überleben zum größten Teil nicht die Fangprozedur, auch nicht, wenn sie unmittelbar nach dem Hol wieder über Bord gegeben werden. Sie sind damit für den Erhalt des betreffenden Bestandes verloren, kommerziell wertlos und verursachen in größeren Mengen einen erheblichen Sortieraufwand, der sich auf die finanzielle Bilanz einer Fangreise negativ auswirkt.

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O objeto de estudo foi o preparo e a administração de medicamentos por cateter pela enfermagem em pacientes que recebem nutrição enteral. O objetivo geral foi investigar o padrão de preparo e administração dos medicamentos por cateter em pacientes que recebem nutrição enteral concomitante. Os objetivos específicos foram apresentar o perfil dos medicamentos preparados e administrados de acordo com a possibilidade de serem administrados por cateter enteral e avaliar o tipo e a freqüência de erros que ocorrem no preparo e administração de medicamentos por cateter. Tratou-se de uma pesquisa com desenho transversal de natureza observacional, sem modelo de intervenção. Foi desenvolvida em um hospital do Rio de Janeiro onde foram observados técnicos de enfermagem preparando e administrando medicamentos por cateter na Unidade de Terapia Intensiva. Foram observadas 350 doses de medicamentos sendo preparados e administrados. Os grupos de medicamentos prevalentes foram os que agem no Sistema Cardiovascular Renal com 164 doses (46,80%), seguido pelos que agem no Sistema Respiratório e Sangue com 12,85% e 12,56% respectivamente. Foram encontrados 19 medicamentos diferentes do primeiro grupo, dois no segundo e cinco no terceiro. As categorias de erro no preparo foram trituração, diluição e misturas. Encontrou-se uma taxa média de 67,71% no preparo de medicamentos. Comprimidos simples foram preparados errados em 72,54% das doses, e todos os comprimidos revestidos e de liberação prolongada foram triturados indevidamente entre sólidos a categoria de erro prevalente foi trituração com 45,47%, preparar misturando medicamentos foi um erro encontrado em quase 40% das doses de medicamentos sólidos. A trituração insuficiente ocorreu em 73,33% das doses de ácido fólico, do cloridrato de amiodarona (58,97%) e bromoprida (50,00%). A mistura com outros medicamentos ocorreu em 66,66% das doses de bromoprida, de besilato de anlodipina (53,33%), bamifilina (43,47%), ácido fólico (40,00%) e ácido acetilsalicílico (33,33%). Os erros na administração foram ausência de pausa e manejo indevido do cateter. A taxa média de erros na administração foi de 32,64%, distribuídas entre 17,14% para pausa e 48,14% para manejo do cateter. A ausência de lavagem do cateter antes foi o erro mais comum e o mais incomum foi não lavar o cateter após a administração. Os medicamentos mais envolvidos em erros na administração foram: cloridrato de amiodarona (n=39), captopril (n=33), cloridrato de hidralazina (n=7), levotiroxina sódica (n=7). Com relação à lavagem dos cateteres antes, ela não ocorreu em 330 doses de medicamentos. O preparo e administração inadequados de medicamentos podem levar à perdas na biodisponibilidade, diminuição do nível sérico e riscos de intoxicações para o paciente. Preparar e administrar medicamentos são procedimentos comuns, porém apresentou altas taxas de erros, o que talvez reflita pouco conhecimento desses profissionais sobre as boas práticas da terapia medicamentosa. Constata-se a necessidade de maior investimento de todos os profissionais envolvidos, médicos, enfermeiros e farmacêuticos nas questões que envolvam a segurança com medicamentos assim como repensar o processo de trabalho da enfermagem.

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The high density of meres and mosses in the Delamere area comes from numerous moraine-hollows formed after the melting of stranded ice-blocks following last glaciation. The main vegetation is of conifers along with some deciduous species and the area was designated as a National Forest Park in 1987. It has been managed since the beginning of the 19th century and is a popular tourist area with walking, orienteering, cycling and educational activities. In recent years this forest park has been attracting over half a million people per year. This paper studies the limnology of different aquatic habitats in the Delamere Forest area in order to give some insight into the waters of a coniferous, temperate forest area, which has so far been largely unexplored. The authors assume therefore, thought that despite apparent large variability in origin, age, surface area, morphometry, catchment size and hydraulic regime, the waters of Delamere Forest might share some revealing chemical and biological features. Seven water-bodies in the Delamere Forest Park area, namely, Black Lake, Blakemere Moss, Delamere Lake, Delamere Quarry, Hatchmere, Windyhowe Farm Spring and Fir Brook were sampled, their water chemistry and dissolved organic carbon and the occurrence of phytoplankton and zooplankton species examined. In a final chapter the authors analyse their findings for patterns.

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在同成分LiTaO3熔体中掺入一定剂量的K2O,采用顶部籽晶提拉法生长掺镁近化学计量比LiTaO3晶体。对晶体分别进行光谱分析,畴结构和抗光损伤阈值的测定。结果表明:与同成分掺镁LiTaO3晶体相比较,其紫外吸收边出现明显蓝移,红外吸收峰变弱。腐蚀晶片的晶相显微镜观察结果表明:掺镁近化学剂量比晶体的畴结构是较为规则的六边形;晶体的抗光致散射能力明显提高。

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Most of the humic substances which occur in natural waters have an iron content of a few percent, indicated by the mg/1 content of organically-bonded carbon. This iron is apparently bound in a complex with the humic substances, for it quite plainly differs in its chemical and physico-chemical properties from what one would expect from the purely inorganic iron-water system. The deviations range from the solubility to the redox behaviour, and thus are frequently the basis of analytical and technical difficulties. The key to the solution of most of this problem lies in a better understanding of the aforementioned bonds between the iron and the humic substances. This paper studies the iron content of the humic substance concentration from a bog lake sample and the complexing of iron by humic substances from the surface of the bog lake.

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In order to measure the diffraction-limit wavefront, we present three types of common-path double-shearing interferometers based on the theory of double shearing. Two pairs of half-aperture or whole-aperture wedge plates are used to introduce opposite tilt to realize the double-shearing function. By comparing the fringe widths in two fields, the marginal wavefront aberration can be obtained. In the paper, we give three different configurations: half-aperture configuration, whole-field configuration and double-interferometer configuration. The half-aperture configuration has the features of high sensitivity, stabilization and easy alignment. For the whole-field configuration, the interference fringes are displayed in two whole fields. Consequently, the divergent or convergent characteristic and aberration types of a wavefront can be identified visually. The whole-field configuration can be changed to the double-interferometer configuration for continuous test. Both small and large wavefront aberrations can be measured by the double-interferometer configuration. The minimum detectable wavefront aberration (W-0)(min) comes to 0.03 lambda. Lastly, we present the experimental results for the three types of double-shearing interferometers.

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ENGLISH: The Inter-American Tropical Tuna Commission operates under the authority and direction of a convention originally entered into by the Republic of Costa Rica and the United States of America. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas in the eastern Pacific Ocean. Under this provision the Republic of Panama adhered in 1953, the Republic of Ecuador in 1961, the United Mexican States in 1964, Canada in 1968 and Japan in 1970. In 1967, Ecuador gave notice of her intent to withdraw from the Commission, and her withdrawal became effective on August 21,1968. The Commission held two meetings in 1977, the 34th from June 27 to 29 in San Diego, California, and the 35th on October 17 and 18 in Mexico City. The Commission adjourned its 35th meeting, held in Mexico City on October 17, and 18, 1977, without agreeing to a resolution for the conservation of yellowfin during 1978. SPANISH: La Comisión Interamericana del Atún Tropical está bajo la autoridad y dirección de una convención la cual fue originalmente formada por la República de Costa Rica y los Estados Unidos de América. La Convención, vigente desde 1950, está abierta a la afiliación de otros gobiernos cuyos nacionales pesquen atún en el Pacífico oriental tropical. Bajo esta medida la República de Panamá se afilió en 1953, la República del Ecuador en 1961, los Estados Unidos Mexicanos en 1964, Canadá en 1968 y el Japón en 1970. En 1967, el Ecuador anunció su intención de retirarse de la Comisión y la renuncia se hizo efectiva el 21 de agosto de 1968. La Comisión celebró dos reuniones en 1977, la XXXIV del 27 al 29 de junio en San Diego (California) y la XXXV del 17 al 18 de octubre en ciudad de México. La Comisión clausuró su XXXV reunión, celebrada en ciudad de México del 17 al 18 de octubre de 1977, sin acordar una resolución para la conservación del atún aleta amarilla en 1978. (PDF contains 164 pages.)

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[ES]En el presente trabajo se tratará de exponer el método de trabajo, el desarrollo y los posibles usos de este dispositivo como un método de control en un marco de uso industrial orientado a la economía