999 resultados para Universal Composition
Resumo:
We investigated developmental changes in the body compositions and fatty acid (FA) profiles of embryos and preparturition larvae of the quillback rockfish (Sebastes maliger). Comparisons of proximate composition data from early-stage embryos with data from hatched preparturition larvae taken from wild-caught gravid females indicated that embryos gain over one-third their weight in moisture while consuming 20% of their dry tissue mass for energy as they develop into larvae. Lipid contributed 60% of the energy consumed and was depleted more rapidly than protein, indicating a protein-sparing effect. Oil globule volume was strongly correlated with lipid levels, affirming its utility as an indicator of energetic status. FA profiles of early embryos differed significantly from those of hatched larvae. Differences in the relative abundances of FAs between early embryos and hatched larvae indicated different FA depletion rates during embryonic development. We conclude that some metabolically important FAs may prove useful in assessing the condition of embryos and preparturition larvae, particularly 20:4n-6, which cannot be synthesized by many marine fish and which is conserved during embryogenesis. Variability in body composition and energy use among rockfish species should be considered when interpreting any measures of condition.
Resumo:
Variation at 14 microsatellite loci was examined in 34 chum salmon (Oncorhynchus keta) populations from Russia and evaluated for its use in the determination of population structure and stock composition in simulated mixed-stock fishery samples. The genetic differentiation index (Fst) over all populations and loci was 0.017, and individual locus values ranged from 0.003 to 0.054. Regional population structure was observed, and populations from Primorye, Sakhalin Island, and northeast Russia were the most distinct. Microsatellite variation provided evidence of a more fine-scale population structure than those that had previously been demonstrated with other genetic-based markers. Analysis of simulated mixed-stock samples indicated that accurate and precise regional estimates of stock composition were produced when the microsatellites were used to estimate stock compositions. Microsatellites can be used to determine stock composition in geographically separate Russian coastal chum salmon fisheries and provide a greater resolution of stock composition and population structure than that previously provided with other techniques.
Resumo:
El presente trabajo se propone analizar desde una perspectiva internacionalista el recorrido del principio de justicia universal en nuestro ordenamiento: inicialmente configurado como un principio de carácter absoluto y cuyo alcance se ha visto drásticamente reducido tras las reformas llevadas a cabo por el legistlador en la última década, especialmente la última de ellas realizada en 2014, hasta el punto de acabar con la misma esencia de esta figura. Expuesto lo anterior, se abordan también las consecuencias que ha traído esta última modificación y las reacciones que la misma ha provocado. Para terminar, trataremos de esclarecer cuáles son las posibles vías de actuación dado el escenario actual.
Resumo:
Because of a lack of fishery-dependent data, assessment of the recovery of fish stocks that undergo the most aggressive form of management, namely harvest moratoriums, remains a challenge. Large schools of red drum (Sciaenops ocellatus) were common along the northern Gulf of Mexico until the late 1980s when increased fishing effort quickly depleted the stock. After 24 years of harvest moratorium on red drum in federal waters, the stock is in need of reassessment; however, fisherydependent data are not available in federal waters and fishery-independent data are limited. We document the distribution, age composition, growth, and condition of red drum in coastal waters of the north central Gulf of Mexico, using data collected from a nearshore, randomized, bottom longline survey. Age composition of the fishery-independent catch indicates low mortality of fish age 6 and above and confirms the effectiveness of the federal fishing moratorium. Bottom longline surveys may be a cost-effective method for developing fishery-independent indices for red drum provided additional effort can be added to nearshore waters (<20 m depth). As with most stocks under harvest bans, effective monitoring of the recovery of red drum will require the development of fishery-independent indices. With limited economic incentive to evaluate non-exploited stocks, the most cost-effective approach to developing such monitoring is expansion of existing fishery independent surveys. We examine this possibility for red drum in the Gulf of Mexico and recommend the bottom longline survey conducted by the National Marine Fisheries Service expand effort in nearshore areas to allow for the development of long-term abundance indices for red drum.
Resumo:
Rockfish (Sebastes spp.) biomass is difficult to assess with standard bottom trawl or acoustic surveys because of their propensity to aggregate near the seafloor in highrelief areas that are inaccessible to sampling by trawling. We compared the ability of a remotely operated vehicle (ROV), a modified bottom trawl, and a stereo drop camera system (SDC) to identify rockfish species and estimate their size composition. The ability to discriminate species was highest for the bottom trawl and lowest for the SDC. Mean lengths and size distributions varied among the gear types, although a larger number of length measurements could be collected with the bottom trawl and SDC than with the ROV. Dusky (S. variabilis), harlequin (S. variegatus), and northern rockfish (S. polyspinis), and Pacific ocean perch (S. alutus) were the species observed in greatest abundance. Only dusky and northern rockfish regularly occurred in trawlable areas, whereas these two species and many more occurred in untrawlable areas. The SDC was able to resolve the height of fish off the seafloor, and some of the rockfish species were observed only near the seafloor in the acoustic dead zone. This finding is important, in that fish found exclusively in the acoustic dead zone cannot be assessed acoustically. For these species, methods such as bottom trawls, long-lines, or optical surveys using line transect or area swept methods will be the only adequate means to estimate the abundance of these fishes. Our results suggest that the selection of appropriate methods for verifying targets will depend on the habitat types and species complexes to be examined.
Resumo:
When estimating parameters that constitute a discrete probability distribution {pj}, it is difficult to determine how constraints should be made to guarantee that the estimated parameters { pˆj} constitute a probability distribution (i.e., pˆj>0, Σ pˆj =1). For age distributions estimated from mixtures of length-at-age distributions, the EM (expectationmaximization) algorithm (Hasselblad, 1966; Hoenig and Heisey, 1987; Kimura and Chikuni, 1987), restricted least squares (Clark, 1981), and weak quasisolutions (Troynikov, 2004) have all been used. Each of these methods appears to guarantee that the estimated distribution will be a true probability distribution with all categories greater than or equal to zero and with individual probabilities that sum to one. In addition, all these methods appear to provide a theoretical basis for solutions that will be either maximum-likelihood estimates or at least convergent to a probability distribut
Resumo:
Fish stomachs from 18 demersal and pelagic fishes from the coast of Terengganu in Malaysia were examined. The components of the fishes’ diets varied in number, weight, and their frequency of occurrence. The major food items in the stomachs of each species were determined using an Index of Relative Importance. A conceptual food web structure indicates that fish species in the study area can be classified into three predatory groups: (1) predators on largely planktivorous or pelagic species; (2) predators on largely benthophagous or demersal species; and (3) mixed feeders that consume both pelagic and demersal species.
Resumo:
O orçamento constitui um instrumento imprescindível para avaliarmos as prioridades de um governo e as disputas existentes entre as diferentes classes sociais no que diz respeito à apropriação dos recursos do fundo público. Neste sentido, uma aproximação cuidadosa acerca das particularidades que vêm assumindo a dinâmica de acumulação capitalista, bem como das contradições que envolvem o processo de luta e implementação das políticas sociais, parecem elementos que contribuem para nos ajudar a entender de que forma esta disputa vem acontecendo. O objetivo deste trabalho é analisar o lugar do gasto social no governo Lula. Para tanto, consideramos importante analisar os principais elementos da dinâmica de acumulação capitalista tendo como referência a constituição do capital financeiro e o processo de financeirização da economia; discutir a relação entre divida pública, financeirização e crise do capital; apreender as tendências da política social, buscando identificar sua configuração na atualidade; resgatar o processo de formação do Brasil para pensar o governo Lula e a dinâmica da luta de classes na atualidade; e analisar os gastos sociais do governo federal, tendo como base a metodologia desenvolvida pelo IPEA, considerando o período de 2004 a 2011. Por entendermos os gastos sociais como reflexo de um processo de correlação de forças que tem, na relação entre capital e trabalho sua dimensão fundante, esta análise não pode ter um fim em si mesma. Ao contrário, entender as particularidades da dinâmica de acumulação no tempo presente é imprescindível para apreender os movimentos do capital e sua força para fazer valer os seus interesses no enfrentamento às resistências impostas pela classe trabalhadora e desta para lutar contra seus grilhões. A atuação do Estado só pode ser entendida em meio a este terreno de luta de classes e suas decisões expressam o poder destas classes de impor suas demandas, além de trazerem consigo o traço das heranças do passado, em especial os vínculos de dependência e subalternidade aos interesses imperialistas. A ausência de ruptura com o capital que marca a ascensão do Partido dos Trabalhadores ao governo federal é permeado por contradições e a análise de seus resultados situa-se em uma série de polêmicas, muitas das quais somente um maior distanciamento histórico permitirá avaliar. Isto não significa que não seja possível empreender um esforço no sentido de identificar as mudanças em curso e levantar as contradições, os limites e as possibilidades abertas pelos mandatos do presidente Lula. De maneira geral, podemos dizer que não houve avanços estruturais significativos neste governo e que a lógica da gestão dos recursos que prioriza o pagamento da dívida pública permanece tendo sofrido alterações pontuais. Entretanto, existem algumas diferenças na composição do gasto social. Estas estão mais atreladas ao provimento de programas voltados para a população de baixa renda do que à melhoria substantiva na garantia das políticas sociais universais. De qualquer forma, seu efeito sobre a melhoria nas condições de vida e de acesso ao consumo de uma parcela da população pode ser sentido.
Resumo:
The interest of HACFRA (self compacting concrete reinforced with steel fibers), is the combination of the residual strength increase and cracking decrease compared to plain concrete by the introduction of steel fibers in the mass with the advantages of the self-compacting. The paper presents an analysis of the influence of different components of the HACRFA and provides their selection, refered to the granular skeleton and to different steel fiber types and amount, in order to obtain an optimization of its features and structural behavior.
Resumo:
The diet composition of 30 fish species belonging to 16 families from the Pacific Coast of Colombia is described. Benthic crustaceans (37.5%) and bony fishes (23.7%, chiefly demersal) were the most important food items for the fish species analyzed. Data on diet composition of the fish species are presented for the first time which can be a source of information for trophic modeling.
The evolution of body muscle composition of the African catfish (Clarias gariepinus) (Burchell 1822)
Resumo:
Changes in body muscle composition of Clarias gariepinus were studied in fish reared from 1.08 g to 383 g mean body weight in a 201-day culture period. Changes in the amount of protein content, dry matter and ash free dry matter in the muscle tissue can be described as a function of body weight. The percentage of protein content was observed to be higher in bigger fish. Fat content was low throughout the fingerling stage. Specific growth rate decreased significantly at 400 g mean body weight (P<0.05) while feed conversion rate increased. The conclusion, based on the culture conditions in this study, is that the optimal weight for harvesting C. gariepinus is 400 g.
Resumo:
The diet composition of fish caught in San Miguel Bay, Philippines, in April and May 1993 was studied. The diets of tiger-tooth croaker (Otolithes ruber), commerson's anchovy (Stolephorus commersonii); and the Indian anchovy (Stolephorus indicus) consisted mainly of zooplankton, primarily crustaceans. The stomach content of orangefin ponyfish (Leiognathus bindus) was found to consist mostly of detritus and unidentified materials. Daily rations estimated were: 1.90 g day super(1) for O. ruber of 17.3 g mean body weight (BW), 0.078 g day super(1) for S. commersonii) of 3.8 g mean BW, 0.062 g day super(1) for S. indicus of 3.9 g mean BW and 0.56 g day super(1) for L. bindus of 7.7 g mean BW.