933 resultados para Forage de données


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A proposta deste estudo é analisar o surgimento de uma nova manifestação do insólito ficcional no cenário literário francês novecentista, caracterizada pela incorporação insólita de eventos históricos. Em consonância com o questionamento pós-moderno sobre as limitações do discurso histórico tradicional, que pretendeu representar fielmente o passado, muitos romances insólitos publicados na França na segunda metade do século XX inseriram o referente histórico posicionando-o no mesmo grau de realidade que os fenômenos insólitos narrados. Levando em conta o quadro geral da pós-modernidade, pretendemos analisar a confluência entre elementos insólitos e referências históricas em Le Livre des Nuits, de Sylvie Germain, publicado em 1984. Tal romance, caracterizado pela fusão entre o ordinário e o extraordinário, apresenta eventos históricos, como a guerra franco-prussiana e as grandes guerras mundiais, que provocam reações sobrenaturais nos personagens. Utilizando a noção de metaficção historiográfica proposta por Linda Hutcheon, analisaremos a incorporação de eventos do passado em Le Livre des Nuits, não como dados históricos, mas como elementos ficcionais que integram a realidade mágica e plural do romance. Esta dissertação visa identificar como os elementos insólitos atribuem uma dimensão sócio-histórica aos personagens, analisando os procedimentos textuais que viabilizam a coexistência entre o real e o irreal no universo romanesco. Para um estudo mais aprofundado dos protocolos narrativos que compõem nosso objeto de estudo, examinaremos também outros romances publicados no mesmo período, como Moi, Tituba, Sorcière... de Maryse Condé e La Sorcière de Marie Ndiaye, que apresentam uma caracterização similar das manifestações insólitas, que se integram harmoniosamente à realidade histórica dos personagens

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Esta tese estuda o registro do léxico brasileiro em dicionários de língua portuguesa do século XIX, numa perspectiva linguística e metalexicográfica. Foram analisados todos os títulos que integram o cânone da dicionarística portuguesa, de caráter geral e monolíngue, no período em questão, quanto à proposta lexicográfica explícita e quanto à microestrutura de uma seção da nominata (todos os brasileirismos iniciados pela letra c). A partir da análise comparativa dos dicionários, foi possível estabelecer, em termos quantitativos e qualitativos, quais edições são relevantes para o registro de termos brasileiros no século XIX: quatro edições do dicionário de Morais e a edição de Caldas Aulete. Embora amplamente utilizada, a marcação diatópica não é alvo de discussão nas obras lexicográficas estudadas. Depreende-se, pelo emprego da marca termo do Brasil, equivalente a brasileirismo, que se trata de um conceito geográfico que, às vezes, coincide com o de origem. Três dicionários de vocábulos brasileiros publicados entre 1852 e 1889 foram identificados como fontes de consulta dos dicionários gerais. Os itens lexicais brasileiros foram observados segundo parâmetros linguísticos e lexicográficos: etimologia, tipo de brasileirismo (lexical ou semântico), regionalismos brasileiros, campos semânticos e tipos de definição. Esses parâmetros permitiram identificar continuidades e rupturas na tradição dicionarística do século XIX e apontar para modos de observar a manutenção dessa tradição no século XX

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•2012 PICES Science: A Note from the Science Board Chairman (pp. 1-6) ◾2012 PICES Awards (pp. 7-9) ◾GLOBEC/PICES/ICES ECOFOR Workshop (pp. 10-15) ◾ICES/PICES Symposium on “Forage Fish Interactions” (pp. 16-18) ◾The Yeosu Declaration, the Yeosu Declaration Forum and the Yeosu Project (pp. 19-23) ◾2013 PICES Calendar (p. 23) ◾Why Do We Need Human Dimensions for the FUTURE Program? (pp. 24-25) ◾New PICES MAFF-Sponsored Project on “Marine Ecosystem Health and Human Well-Being” (pp. 26-28) ◾The Bering Sea: Current Status and Recent Trends (pp. 29-31) ◾Continuing Cool in the Northeast Pacific Ocean (pp. 32, 35) ◾The State of the Western North Pacific in the First Half of 2012 (pp. 33-35) ◾New Leadership in PICES (pp. 36-39)

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This paper is based on an attempt to assemble the existing knowledge of the silverside, Menidia menidia, and to contribute to what is known about the life history of this species. A vast amount of work is needed on the ecological relationships between the food fish and the forage fish. One of the most important forage fishes on the Atlantic Coast is the silverside. To understand the inter-relationships between the food fish and the forage fish it is necessary first to understand the life histories of both. For this reason it is important that the life history of this species be studied.

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多效唑(MET)是一种新型的植物生长调节剂.本文以多杆多穗青饲玉米为材料详细地研究了它征组织培养中的作用和生物学效应,并对它的作用机理也进行了初步的探讨。 研究结果表明:(1)适宜浓度的MET能够提高不同外植体愈伤组织的诱导率;(2)2~4 mg/lMET能改善愈伤组织的质量,提高愈伤组织的分化率、绿苗形成率、根的形成率和正常苗/异常苗的比值;(3)壮苗培养,MEP能使再生苗形态结构和生理等方面均发生较大的变化,并使其生长健壮,根系发达,移裁入土后成活率提高,达80%以上;(4)在再生苗的长期保存中,MET也具有良好的作用效应;(5)在继代培养中,MET处理后,愈伤组织的生长值下降;过氧化物酶活性和IAA氧化酶活性增加, 内源乙烯的释放量上升;外源GA3可逆转MET的作用效应,IAA、kt、ABA没有逆转效应,相反,ABA与MET对抑制愈防组织的生长具有加成效应.MET的作用机班可能是:通过改变细胞内酶的活性和内源激素的含量水平来控制愈伤组织细胞的生长、分化以及再生植株的生长和发育。 MET在玉米组培中所表现出的良好的作用效应表明:对于解决植物组织培养中所普遍存在的一些问题,用MET处理可能会变成一种有效的方法。展示出MET在植物生物技术领域也具有广泛的应用前景。

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In the Caribbean, many coral reef associated fishes have been observed making diel migrations, yet little is known about the detailed movement pathways and space use patterns of individual fish. Often these migrations occur along temporally or spatially consistent corridors that connect preferred resting and foraging habitats. Recent analysis of gut contents from Haemulids and Lutjanids, has provided evidence that these species forage in seagrass beds and other habitats near their coral reef refuges. Few studies have provided direct and spatially explicit evidence of nocturnal migrations and detailed day and night space use patterns for individual fish. This study integrated manual acoustic telemetry to track two common reef species, the bluestriped grunt (Haemulon sciurus) and schoolmaster snapper (Lutjanus apodus) throughout their daily home range. Space use patterns of these species were then examined using Geographical Information System (GIS) tools to link movement behavior to seascape structure derived in a benthic habitat map. This study represents a novel integration of spatial technologies to enhance our understanding of the movement ecology of adult H. sciurus and L. apodus.

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本工作用BT基因、PinⅡ基因和bar基因对青饲玉米、谷子进行了基因转化的研究,并且对转基因的受体、转基因的方法、转化后的筛选、检测及植株再生等问题进行了探讨。 玉米胚性细胞系,包括胚性愈伤组织和胚性细胞悬浮系,可作为基因转化的受体,它亦是原生质体培养的关键。玉米的基因型对胚性细胞系的获得有很大的影响。在相同的培养条件下,九个青饲玉米品系都得到了I型愈伤组织,但仅有两个品系(232和235)得到了胚性细胞系(L32和L35)。幼胚的长度及年龄也是影响诱导形成胚性愈伤组织的一个重要因素,最佳胚长是1-1.5mm,最佳胚龄是授粉后10-12天的幼胚。另外,适当提高蔗糖浓度对胚性细胞悬浮系的建立及保持均有好处。 从玉米原生质体培养获得了再生植株.在此基础上用电激法和PEG法将BT基因导入玉米原生体,发现在原生质体培养过程中,同对照相比,第一次细胞分裂及形成愈伤组织的时间往后推移. 诱导玉米I型愈伤组织没有基因型的限制,可以从大多数玉米品系中得到。并且玉米I型愈伤组织具有极强的分化能力.我们将玉米I型愈伤组织作为基因枪法转化的受体,获得了转基因工程植株。目前,尚未见这方面的报道. 基因枪法转化玉米胚性细胞系,得到抗性愈伤组织的效率约为1/40。用直径约3mm的玉米I型愈伤组织块作基因枪法转化受体,转化后经筛选平均每块可得到1-4个抗性愈伤组织系。用PEG和电激法转化玉米原生质体,转化后原生质体再生愈伤组织中,抗性愈伤组织的得率为9.3%和8.9%, 基因枪法适应完整的细胞和组织的转化,可较快得到抗性植株,在玉米基因转化研究中, 为了较快地得到转化植株,用基因枪法较电激法和PEG法更好,在玉米三种基因转化的受体中(原生质体、胚性细胞系和I型愈伤组织),以I型愈伤组织作受体最好,用它作受体可以避免原生质体培养的困难,克服获得胚性细胞系的基因型的限制。 胚性细胞系对抗菌素的耐受性随继代时间增长而增加.I型愈伤组织对抗菌素的耐受性 同愈伤组织块的大小呈正相关。 由于玉米愈伤组织对卡那霉素的本底抗性较高,所以需要用高浓度(800mg/L)的卡那霉 素进行筛选,过高的选择压力对芽的分化有抑制作用.用电激和PEG处理后的原生质体再生的愈伤组织,经卡那霉素筛选出的抗性愈伤组织未能得到再生植株。而对照则得到了再生植株。用PPT和Hyg筛选出的抗性愈伤组织得到了再生植株. 用PCR和Southern杂交对抗性愈伤组织和再生植株进行检测,证明外源基因已整合到 玉米基因组中。得到了携有BT基因、bar基因或PinⅡ基因的愈伤组织或工程植株。 用豫谷一号的幼穗诱导获得了胚性愈伤组织,基因枪转化后,经PPT筛选得到抗性愈伤组织。每个5cm的培养皿内装有谷子胚性愈伤组织约0.5g,经筛选后可得到5-10块抗性愈伤组织,此PPT抗性的愈伤组织用PCR和Southern杂交检测,证明bar基因已整合到了谷子的基因组中。从转化愈伤组织中已分化出了再生植株。

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To demonstrate the utility of distributional surveys for assessing relative abundance and trends in counts for a discrete area of coastline, aerial survey data from Sarasota County, Florida, USA, were analyzed for the years 1987 to 2006. The study area was divided into 3 regions: the Sarasota Bay Region (SBR; N = 353 surveys), Lemon Bay (N = 368), and the Myakka River (N = 209). Manatee counts varied significantly across seasons (p < 0.0001) for all 3 regions. Manatees within Sarasota County utilized open bays primarily in the warmer months. Such usage may have been influenced by resource availability. Conversely, usage of the Myakka River peaked in winter months when manatees seek warm-water refugia such as Warm Mineral Spring. Marginal means for yearly counts within Lemon Bay and the SBR increased significantly, beginning midway through the survey period (1996) until the early 2000s. In contrast, mean yearly counts within the Myakka River decreased over this time period. After record lows in 2003 for Lemon Bay and the Myakka River, and a considerable decline in 2004 for the SBR, mean yearly counts for all 3 regions showed an increasing trend over the remaining 2 yr of the study. Greater protection of manatee habitat and availability of forage coincided with the increase in numbers of manatees using Sarasota County waters during the 1990s, and the subsequent decline in numbers may be indicative of the increase in mortality in recent years due to watercraft collisions and severe red tide events.

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Information is summarized on juvenile salmonid distribution, size, condition, growth, stock origin, and species and environmental associations from June and August 2000 GLOBEC cruises with particular emphasis on differences related to the regions north and south of Cape Blanco off Southern Oregon. Juvenile salmon were more abundant during the August cruise as compared to the June cruise and were mainly distributed northward from Cape Blanco. There were distinct differences in distribution patterns between salmon species: chinook salmon were found close inshore in cooler water all along the coast and coho salmon were rarely found south of Cape Blanco. Distance offshore and temperature were the dominant explanatory variables related to coho and chinook salmon distribution. The nekton assemblages differed significantly between cruises. The June cruise was dominated by juvenile rockfishes, rex sole, and sablefish, which were almost completely absent in August. The forage fish community during June comprised Pacific herring and whitebait smelt north of Cape Blanco and surf smelt south of Cape Blanco. The fish community in August was dominated by Pacific sardines and highly migratory pelagic species. Estimated growth rates of juvenile coho salmon were higher in the GLOBEC study area than in areas farther north. An unusually high percentage of coho salmon in the study area were precocious males. Significant differences in growth and condition of juvenile coho salmon indicated different oceanographic environments north and south of Cape Blanco. The condition index was higher in juvenile coho salmon to the north but no significant differences were found for yearling chinook salmon. Genetic mixed stock analysis indicated that during June, most of the Chinook salmon in our sample originated from rivers along the central coast of Oregon. In August, chinook salmon sampled south of Cape Blanco were largely from southern Oregon and northern California; whereas most chinook salmon north of Cape Blanco were from the Central Valley in California.

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The increase in harbor seal (Phoca vitulina richardsi) abundance, concurrent with the decrease in salmonid (Oncorhynchus spp.) and other fish stocks, raises concerns about the potential negative impact of seals on fish populations. Although harbor seals are found in rivers and estuaries, their presence is not necessarily indicative of exclusive or predominant feeding in these systems. We examined the diet of harbor seals in the Umpqua River, Oregon, during 1997 and 1998 to indirectly assess whether or not they were feeding in the river. Fish otoliths and other skeletal structures were recovered from 651 scats and used to identify seal prey. The use of all diagnostic prey structures, rather than just otoliths, increased our estimates of the number of taxa, the minimum number of individuals and percent frequency of occurrence (%FO) of prey consumed. The %FO indicated that the most common prey were pleuronectids, Pacific hake (Merluccius productus), Pacific stag-horn sculpin (Leptocottus armatus), osmerids, and shiner surfperch (Cymatogaster aggregata). The majority (76%) of prey were fish that inhabit marine waters exclusively and fish found in marine and estuarine areas (e.g. anadromous spp.) which would indicate that seals forage predominantly at sea and use the estuary for resting and opportunistic feeding. Salmonid remains were encountered in 39 samples (6%); two samples contained identifiable otoliths, which were determined to be from chi-nook salmon (O. tshawytscha). Because of the complex salmonid composition in the Umpqua River, we used molecular genetic techniques on salmonid bones retrieved from scat to discern species that were rare from those that were abundant. Of the 37 scats with salmonid bones but no otoliths, bones were identified genetically as chinook or coho (O. kisutch) salmon, or steelhead trout (O. mykiss) in 90% of the samples.

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The diet of Pacific cod (Gadus macrocephalus) in the area of Pavlof Bay, Alaska, was studied in the early 1980s by Albers and Anderson (1985). They found that the dominant prey species were forage species like pandalid shrimp, capelin (Mallotus villosus), and walleye pollock (Theragra chalcogramma). The shrimp fishery in Pavlof Bay began in 1968 and closed in 1980 because of low shrimp abundance (Ruccio and Worton1). Survey data indicate that, during the period between 1972 and 1997, the abundance of forage species such as pandalid shrimp and capelin declined and higher trophic-level groundfish such as Pacific cod increased. There is a general recognition that a long-term ocean climate shift in the Gulf of Alaska has been partially responsible for the observed reorganization of the community structure (Anderson and Piatt, 1999).

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The effects of seasonal and regional differences in diet composition on the food requirements of Steller sea lions (Eumetopias jubatus) were estimated by using a bioenergetic model. The model considered differences in the energy density of the prey, and differences in digestive efficiency and the heat increment of feeding of different diets. The model predicted that Steller sea lions in southeast Alaska required 45–60% more food per day in early spring (March) than after the breeding season in late summer (August) because of seasonal changes in the energy density of the diets (along with seasonal changes in energy requirements). The southeast Alaska population, at 23,000 (±1660 SD) animals (all ages), consumed an estimated 140,000 (±27,800) t of prey in 1998. In contrast, we estimated that the 51,000 (±3680) animals making up the western Alaska population in the Gulf of Alaska and Aleutian Islands consumed just over twice this amount (303,000 [±57,500] t). In terms of biomass removed in 1998 from Alaskan waters, we estimated that Steller sea lions accounted for about 5% of the natural mortality of gadids (pollock and cod) and up to 75% of the natural mortality of hexagrammids (adult Atka mackerel). These two groups of species were consumed in higher amounts than any other. The predicted average daily food requirement per individual ranged from 16 (±2.8) to 20 (±3.6) kg (all ages combined). Per capita food requirements differed by as much as 24% between regions of Alaska depending on the relative amounts of low–energy-density prey (e.g. gadids) versus high–energy-density prey (e.g. forage fish and salmon) consumed. Estimated requirements were highest in regions where Steller sea lions consumed higher proportions of low–energy-density prey and experienced the highest rates of population decline

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Large (>458 mm) striped bass (Morone saxatilis) are dominant predators in Chesapeake Bay. In recent years, the Chesapeake Bay stock of striped bass has increased dramatically, raising concerns about their predatory impact and their forage requirements. In response to these concerns and the need for more recent ecological studies, this investigation was conducted to characterize feeding habits of large striped bass in Chesapeake Bay. Stomach contents from 1225 striped bass from 458 to 1151 mm TL were examined in the spring and fall of 1997 and 1998. Striped bass consumed 52 different species of vertebrates and invertebrates; however, only a few species of clupeoid and sciaenid fishes dominated diets across both the seasons and size ranges of striped bass examined. Of finfish species, menhaden (Brevoortia tyrannus) was the dominant prey in most areas and gizzard shad (Dorosoma cepedianum) replaced menhaden in importance in lower salinity waters. Spot (Leiostomus xanthurus) and other sciaenid fishes and anadromous herrings (Alosa spp.) also contibuted large percentages of striped bass diet. Although pelagic schooling fishes formed the majority of the diet, benthic fishes contributed a higher percentage to the diet than in previous studies of striped bass diet composition.

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Each spring horseshoe crabs (Limulus polyphemus L.) emerge from Delaware Bay to spawn and deposit their eggs on the foreshore of sandy beaches (Shuster and Botton, 1985; Smith et al., 2002a). From mid-May to early June, migratory shorebirds stopover in Delaware Bay and forage heavily on horseshoe crab eggs that have been transported up onto the beach (Botton et al., 1994; Burger et al., 1997; Tsipoura and Burger, 1999). Thus, estimating the quantity of horseshoe crab eggs in Delaware Bay beaches can be useful for monitoring spawning activity and assessing the amount of forage available to migratory shorebirds.