965 resultados para Grow cicero
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English: For nearly a century, fisheries scientists have studied marine fish stocks in an effort to understand how the abundances of fish populations are determined. During the early lives of marine fishes, survival is variable, and the numbers of individuals surviving to transitional stages or recruitment are difficult to predict. The egg, larval, and juvenile stages of marine fishes are characterized by high rates of mortality and growth. Most marine fishes, particularly pelagic species, are highly fecund, produce small eggs and larvae, and feed and grow in complex aquatic ecosystems. The identification of environmental or biological factors that are most important in controlling survival during the early life stages of marine fishes is a potentially powerful tool in stock assessment. Because vital rates (mortality and growth) during the early life stages of marine fishes are high and variable, small changes in those rates can have profound effects on the properties of survivors and recruitment potential (Houde 1989). Understanding and predicting the factors that most strongly influence pre-recruit survival are key goals of fisheries research programs. Spanish: Desde hace casi un siglo, los científicos pesqueros han estudiado las poblaciones de peces marinos en un intento por entender cómo se determina la abundancia de las mismas. Durante la vida temprana de los peces marinos, la supervivencia es variable, y el número de individuos que sobrevive hasta las etapas transicionales o el reclutamiento es difícil de predecir. Las etapas de huevo, larval, y juvenil de los peces marinos son caracterizadas por tasas altas de mortalidad y crecimiento. La mayoría de los peces marinos, particularmente las especies pelágicas, son muy fecundos, producen huevos y larvas pequeños, y se alimentan y crecen en ecosistemas acuáticos complejos. La identificación los factores ambientales o biológicos más importantes en el control de la supervivencia durante las etapas tempranas de vida de los peces marinos es una herramienta potencialmente potente en la evaluación de las poblaciones. Ya que las tasas vitales (mortalidad y crecimiento) durante las etapas tempranas de vida de los peces marinos son altas y variables, cambios pequeños en esas tasas pueden ejercer efectos importantes sobre las propiedades de los supervivientes y el potencial de reclutamiento (Houde 1989). Comprender y predecir los factores que más afectan la supervivencia antes del reclutamiento son objetivos clave de los programas de investigación pesquera.
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As cianobactérias Microcystis aeruginosa e Planktothrix agardhii são espécies formadoras de florações comuns em ecossistemas aquáticos eutrofizados. Nestes ambientes, a disponibilidade de luz é um dos fatores determinantes para o desenvolvimento e estruturação da comunidade fitoplanctônica. O presente estudo teve como objetivo investigar o efeito da luz na fisiologia de cepas de cianobactérias (M. aeruginosa e P. agardhii), avaliando o crescimento, a variabilidade inter e intra-específica e a competição por luz. Para tanto foram realizados cultivos estanques em diferentes intensidades luminosas (10, 40, 60, 100 e 500 mol m-2 s-1) e calculadas as taxas de crescimento e os rendimentos máximos das culturas. O requerimento mínimo de luz de cada cepa foi determinado em experimentos com monoculturas em sistemas de cultivo contínuo (quimiostatos) sob condições de limitação de luz. A competição por luz foi avaliada através de experimentos com biculturas em quimiostatos. Foi observada variabilidade intra e inter-específica das cepas, nas diferentes intensidades luminosas testadas. Em 500 μmol m-2 s-1, as cepas de M. aeruginosa obtiveram maior biomassa do que P. agardhii, corroborando a maior sensibilidade de P. agardhii luz. Embora com rendimento máximo menor, P. agardhii cresceu em intensidades luminosas consideradas elevadas para a espécie, 100 e 500 μmol m-2 s-1. Estes resultados evidenciam a capacidade de P. agardhii ocorrer em ambientes com grandes amplitudes de luminosidade. Na intensidade de 10 μmol m-2 s-1, M. aeruginosa e P. agardhii apresentaram crescimento semelhante, demonstrando a habilidade das duas espécies em crescer com pouca luz. Nas monoculturas em quimiostato, sob condições de limitação de luz, as cepas de M. aeruginosa atingiram maior biomassa durante o equilíbrio (steady-state) do que P. agadhii, refletindo uma capacidade suporte mais elevada, enquanto que os valores de requerimento mínimo de luz foram semelhantes entre as duas espécies. Ao competirem, M. aeruginosa superou P. agardhii imediatamente após o início do experimento. Esse rápido crescimento resultou na dominância de M. aeruginosa em todos os pares de cepas testados e, em dois casos, ocorreu exclusão competitiva de P. agardhii. Quando não ocorreu exclusão, P. agardhii conseguiu manter-se no sistema com uma baixa biomassa (ca.15%). Estes resultados ajudam a entender a co-ocorrência destas espécies no ambiente e a dominância de M. aeruginosa mesmo em condições de baixa luminosidade.
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Lattice-matched (Delta(a/a) = 1.8-3.4%) (001) LiGaO2 substrates have been employed for the first time to grow ZnO thin films by pulsed-laser deposition at 350-650 degrees C with oxygen partial pressure of 20Pa. XRD shows that a highly c-axis-oriented ZnO film can be deposited on (001) LiGaO2 substrate at 500 degrees C. AFM images reveal the surfaces of as-deposited ZnO films are smooth and root-mean-square values are 6.662, 5.765 and 6.834 nm at 350, 500 and 650 degrees C, respectively. PL spectra indicate only near-band-edge UV emission appears in the curve of ZnO film deposited at 500 degrees C. The deep-level emission of ZnO film deposited at 650 degrees C probably results from Li diffusion into the film. All the results illustrate substrate temperature plays a pretty important role in obtaining ZnO film with a high quality on LiGaO2 substrate by pulsed-laser deposition. (c) 2006 Elsevier B.V. All rights reserved.
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Thin films of beta barium borate have been prepared by liquid phase epitaxy on Si2+-doped alpha-BaB2O4 (alpha-BBO, the high temperature phase of barium berate) (001) and (110) substrates. The results of X-ray diffraction indicate that the films show highly (001) preferred orientation on (001)-oriented substrates while the films grown on (110) substrates are textured with (140) orientation. The crystallinity of these films was found to depend on growth temperature, rotation rate, dip time and orientation of substrate. Growth conditions were optimized to grow films with (001) orientation on (001) substrates reproducibly. The films show second harmonic generation of 400 nm light upon irradiation with 800 nm Ti: Sapphire femtosecond laser light. (c) 2005 Elsevier B.V. All rights reserved.
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Cerium-doped lutetium pyrosilicate crystal, Ce:Lu2Si2O7 (Ce:LPS), was grown by the Czochralski method. The segregation coefficient of Ce3+ ion was studied by the ICP-AES method. X-ray diffraction analysis showed that the structure of Ce:LPS crystal was monoclinic symmetry with space group of C2/m. Perfect cleavage planes (110) and imperfect cleavage planes (001) were observed by optical microscope. The reasons why it is difficult to grow crack-free crystals were studied. After optimized growth parameters, a Ce:LPS crystal with dimension of Phi 25 x 30 mm was grown, which is colorless, high optical quality, cracking-free and no inclusions. The transmittance of Ce:LPS crystal from 380 to 800 nm is over 82% and there is no observable absorption. (c) 2005 Elsevier B.V. All rights reserved.
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A presente Dissertação visa pesquisar a contribuição da Psicanálise ao atendimento a idosos envolvidos em situação de violência, tomando como base a experiência como psicólogo numa Instituição Jurídica. A partir da constatação de que na grande maioria dos casos pesquisados esta violência decorre de um conflito familiar, onde se verifica a participação do idoso em sua manutenção, o presente estudo demonstra a importância de levá-lo a se implicar em sua posição subjetiva e a perceber que a solução do problema passa pela assunção subjetiva do ato e pelo resgate da sua história e da sua relação com o agressor. Baseada no conceito de sujeito do inconsciente, esta Dissertação defende a ideia de que o sujeito do inconsciente não envelhece. Também na terceira idade é possível apostar na retificação subjetiva. Para tanto, aborda a responsabilidade do sujeito pelo desejo e gozo diferenciada da responsabilidade jurídica.
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Well-aligned ZnO films have been successfully prepared by using low-temperature hydrothermal approach on (0001) sapphire substrates that were pre-coated with a ZnO nano-layer by dip-coating. The characterizations of scanning electron microscopy (SEM) and X-ray diffraction (XRD) indicate that the ZnO films consist of hexagonal rods that grow along the c axis based on the sapphire substrates. It is found that the size of ZnO rods can be adjusted by an aqueous solution with some methenamine. (c) 2006 Elsevier B.V. All rights reserved.
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Seasonal variations of abundance and vertical distribution over the shelf are investigated for Ostracoda, Cladocera and Cirripede larvae. The main characteristics of the environment are the periodical enrichments mainly caused by upwellings, secondly by the river floods. Ostracoda abundance variations approximately follow phytoplankton outburst. Breeding occurs all over the year. Their vertical distribution is correlated with a discontinuity layer. Diurnal migration, when it occurs in warm season consists in an upward movement during the night towards surface layers. The Ostracoda inhabit bottom layers during the day and migrate at night in intermediate and surface layers. For the main two species of Cladocera, Penilia avirostris and Evadne tergestina, abundance periods follow upwellings, especially during the main cool season. However, Cladocera can grow in low salinity but rich waters. On average Penilia inhabits more superficial waters in cold than in warm seasons. Cirripede nauplii and cypris are more abundant off rocky coasts. Their maxima are in the upwelling periods.
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The angling season for non-migratory brown trout, in the Environment Agency (EA) North West Region, runs from March 15th to September 30th. Each year, large numbers of farm reared brown trout are stocked into the rivers of the North West Region's Central Area. In 1994, approximately 20,000 brown trout were introduced into the River systems of the Lune, Wyre and Ribble by local angling clubs and fishery owners. Most of these fish were stocked at a length greater than that defined by local byelaws as the takeable size (200mm). Introductions are made to supplement the existing wild brown trout populations within the river and increase the probability of an angler catching a fish. Stocking with fish of a sufficient length allows the successful angler to remove the catch for their own use. In this way, stretches of the rivers are effectively managed as "put and take" fisheries for brown trout. A number of brown trout fingerlings are also introduced each year by angling clubs and fishery owners. These are stocked with the expectation that the fish will survive in the river to grow, over-winter, and eventually attain a takable size with an increased degree of "wildness". The lower cost of fingerlings, as opposed to trout of a takable length, makes their introduction more attractive to angling clubs since a greater number can be stocked for a given cost. Although the practise of stocking brown trout has occurred for many years in the Central Area, there is little information of its success in terms of increasing anglers catches, or the survival offish introduced. This study was initiated to determine the recapture rates by angling of brown trout following their introduction into a river fishery. The information gained from this study can then be used to give guidance to angling clubs and fishery owners on the optimal strategies for stocking fish.
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使用倾斜角沉积(GLAD)的电子束蒸发技术,制备了倾斜角度在60°~85°之间的ZnS双折射雕塑薄膜(STF)。使用X射线衍射(XRD)和扫描电镜(SEM)检测了ZnS薄膜的结晶状态和断面形貌,使用Lamda-900分光光度计测量了薄膜在不同的偏振光入射时的透过率。研究发现,室温下倾斜沉积ZnS薄膜断面为倾斜柱状结构,且薄膜的结晶程度不高。在相同的监控厚度时,随倾斜角度增大,沉积到基片上的薄膜厚度逐渐变小,但仍然大于余弦曲线显示的理论厚度。根据偏振光垂直入射时薄膜的透过光谱计算了不同角度沉积的薄膜的折射率
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Growth rates of male and female tigerfish Hydrocynus vittatus were determined from length/frequencies of fish from the Sanyati Basin and Sinamwenda estuary, Lake Kariba. Growth rates were similar in both sexes for the first two years, after which females grew faster and reached a greater length. Fish from the Sanyati Basin appeared to grow slightly faster than those from the Sinamwenda Estuary.
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Plasticine strips are rolled between cylindrical rollers to model the phenomenon of material transfer in metal rolling. Strips of thin plastic film ('clingfilm') on the plasticine strip are used to model the oxide layer that covers the surface of aluminium. The effect of gaps opening up between the clingfilm strips is investigated. It is found that the percentage area of the exposed strip giving rise to transfer of material increases with the gap width. The evidence strongly suggests that plasticine particles transferred to the rolls are able to pick off plasticine from the strip on successive passes. Larger plasticine particles are more likely to show this behaviour and consequently grow in size. The results confirm the usefulness of plasticine as a suitable material to investigate transfer layer formation in metal rolling, and help inform development of experimental procedures to study the evolution of real metal transfer layers. © 2007 Elsevier B.V. All rights reserved.
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Maternal effects on the quality of progeny can have direct impacts on population productivity. Rockfish are viviparous and the oil globule size of larvae at parturition has been shown to have direct effects on time until starvation and growth rate. We sampled embryos and preparturition larvae opportunistically from 89 gravid quillback rockfish (Sebastes maliger) in Southeast Alaska. Because the developmental stage and sampling period were correlated with oil globule size, they were treated as covariates in an analysis of maternal age, length, and weight effects on oil globule size. Maternal factors were related to developmental timing for almost all sampling periods, indicating that older, longer, and heavier females develop embryos earlier than younger, shorter, or lighter ones. Oil globule diameter and maternal length and weight were statistically linked, but the relationships may not be biologically significant. Weight-specific fecundity did not increase with maternal size or age, suggesting that reproductive output does not increase more quickly as fish age and grow. Age or size truncation of a rockfish population, in which timing of parturition is related to age and size, could result in a shorter parturition season. This shortening of the parturition season could make the population vulnerable to fluctuating environmental conditions.
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A new description of growth in blacklip abalone (Haliotis rubra) with the use of an inverse-logistic model is introduced. The inverse-logistic model avoids the disadvantageous assumptions of either rapid or slow growth for small and juvenile individuals implied by the von Bertalanffy and Gompertz growth models, respectively, and allows for indeterminate growth where necessary. An inverse-logistic model was used to estimate the expected mean growth increment for different black-lip abalone populations around southern Tasmania, Australia. Estimates of the time needed for abalone to grow from settlement until recruitment (at 138 mm shell length) into the fishery varied from eight to nine years. The variability of the residuals about the predicted mean growth increments was described with either a second inverse-logistic relationship (standard deviation vs. initial length) or by a power relationship (standard deviation vs. predicted growth increment). The inverse-logistic model can describe linear growth of small and juvenile abalone (as observed in Tasmania), as well as a spectrum of growth possibilities, from determinate to indeterminate growth (a spectrum that would lead to a spread of maximum lengths).
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[EN] The goal of this contribution is twofold: on the one hand, to review two relatively recent contributions in the field of Eskimo-Aleut historical linguistics in which it is proposed that Eskimo-Aleut languages are related genealogically to Wakashan (Holst 2004) and?/or Nostratic (Krougly-Enke 2008). These contributions can be characterized by saying that their authors have taken little care to be diligent and responsible in the application of the comparative method, and that their familiarity with the languages involved is insufficient. Eskimo-Aleut languages belong to a very exclusive group of language families that have been (and still are) used, sometimes compulsively, in the business of so-called “long-range comparisons”. Those carrying out such studies are very often unaware of the most basic facts regarding the philological and linguistic traditions of those languages, as a result of what mountains of very low quality works with almost no-relevancy for the specialist grow every year to the desperation of the scientific community, whose attitude toward them ranges from the most profound indifference to the toughest (and most explicit) critical tone. Since Basque also belongs to this group of “compare-with-everything-you-come- across” languages, it is my intention to provide the Basque readership with a sort of “pedagogical case” to show that little known languages, far from underrepresented in the field, already have a very long tradition in historical and comparative linguistics, i.e. nobody can approach them without previous acquaintance with the materials. Studies dealing with the methodological inappropriateness of the Moscow School’s Nostratic hypothesis or the incorrectness of many of the proposed new taxonomic Amerindian subfamilies (several of them involving the aforementioned Wakashan languages), that is to say, the frameworks on which Krougly-Enke and Holst work, respectively, are plenty (i.a. Campbell 1997: 260-329, Campbell & Poser 2008: 234-96), therefore there is no reason to insist once more on the very same point. This is the reason why I will not discuss per se Eskimo-Aleut–Wakashan or Eskimo-Aleut–Nostratic. On the contrary, I will focus attention upon very concrete aspects of Krougly-Enke and Holst´s proposals, i.e. when they work on “less ambitious” problems, for example, dealing with the minutiae of internal facts or analyzing certain words from the sole perspective of Eskimo-Aleut materials (in other words, those cases in which even they do not invoke the ad hoc help of Nostratic stuff). I will try to explain why some of their proposals are wrong, demonstrate where the problem lies, and fix it if possible. In doing so, I will propose new etymologies in an attempt at showing how we may proceed. The main difference between this and handbook examples lies in the reality of what we are doing: this is a pure etymological exercise from beginning to end. I will try to throw a bit of light on a couple of problematic questions regarding Aleut historical phonology, demonstrating how much work should be done at the lowest level of the Eskimo-Aleut pyramid; it is technically impossible to reach the peak of the pyramid without having completed the base. As far as Aleut is regarded, I will mainly profit not only from the use of the traditional philological analysis of Aleut (and, eventually, of Eskimo) materials, but also of diachronic typology, bringing into discussion what in my opinion seems useful, and in some cases I think decisive, parallels. It is worth noting that this paper makes up yet another part of a series of exploratory works dealing with etymological aspects of the reconstruction of Proto-Eskimo-Aleut, with special emphasis on Aleut (vid. i.a. Alonso de la Fuente 2006/2007, 2008a, 2008b, 2010a), whose main goal is to become the solid basis for an etymological dictionary of the Aleut language, currently in progress.