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- Weighted hardy and singular operators in morrey spacesPublication . Samko, NatashaWe study the weighted boundedness of the Cauchy singular integral operator S-Gamma in Morrey spaces L-p,L-lambda '(Gamma) on Curves satisfying the arc-chord condition, for a class of "radial type" almost monotonic weights. The non-weighted boundedness is shown to hold on an arbitrary Carleson curve. We show that the weighted boundedness is reduced to the boundedness of weighted Hardy operators in Morrey spaces L-p,L-lambda(0. e), e > 0. We find conditions for weighted Hardy operators to be bounded in Morrey spaces. To cover the case of curves we also extend the boundedness of the Hardy-Littlewood maximal operator in Morrey spaces, known in the Euclidean setting, to the case of Carleson curves. (c) 2008 Elsevier Inc. All rights reserved.
- Effects of feeding levels on growth response, body composition, and energy expenditure in blackspot seabream, pagellus bogaraveo, juvenilesPublication . de Almeida Ozorio, Rodrigo Otavio; Andrade, Carlos; Freitas Andrade Timoteo, Viriato Manuel; Eugénio Castanheira Conceição, Luis; Pinheiro Valente, Luisa MariaAlthough reported as a slow growing species, to date information regarding nutritional dynamics of blackspot seabream, Pagellus bogaraveo, is limited, especially during ongrowing phase. This study determined the effects of different feeding levels on growth response, body composition, and energy expenditure of blackspot seabream juveniles (initial weight = 64 g). Fish were allocated in nine indoor tanks (15 fish per tank) and fed a basal diet twice daily at increasing levels (2.5, 3.3, and 4.1 g feed/kg(0.8)/d) for 138 d. Growth response decreased with decreasing feeding levels, but only at 2.5 g feed/kg(0.8)/d (P < 0.001). Differences in growth rates were positively correlated with body lipid content (r(2) = 0.90). Net protein utilization decreased with each increase in feeding level. The energy requirement for zero growth (maintenance) and the estimated energy loss on starvation were calculated as 22.6 and 17.9 kJ/kg(0.8)/d, respectively. The energy cost for protein and lipid gain was calculated as 3.8 and 1.4 kJ/kJ energy deposited, respectively. This study suggested that blackspot seabream may grow slower than the other close-related species because of its higher demand of dietary protein energy in favor of lipid deposition.
- Os senhores sexuais e outras histórias verdadeirasPublication . Nogueira, AdrianaArtigo de jornal sobre etimologias e falas etimologias.
- Photosynthesis and growth in macroalgae: linking functional-form and power-scaling approachesPublication . de los Santos, Carmen B.; Pérez-Lloréns, J.L.; Vergara, J.J.Grouping species into functional-form groups and measuring directly their surface area to volume ratio are 2 common approaches to forecast primary production of marine macroalgae. A link between the functional-form model (FFM) and the power-scaling approach (PSA) for a wide variety of marine macroalgae has been attempted for the first time in the present work. To test both approaches, thalli of 44 species of marine benthic macroalgae were collected from intertidal zones adjacent to Cádiz Bay. Metabolic rates, tissue nutrient content, surface area to biomass ratio (SA/B) and specific growth rates were measured for these species. PSA slopes were close to 2/3 power for growth rate, while metabolic rates scaled very close to, or matched, 3/4 power. The FFM descriptive model provided similar results to the PSA when it was transformed to a numerical model through the SA/B ratio. Even though both models appear to be valid, the problems derived from species allocation into morphological groups, and other previous criticisms, make the direct use of SA/B ratios more suitable for representing primary production in macroalgal functional groups in numerical models of coastal ecosystems.