On the relevance of Reynolds stresses in resolvent analyses of turbulent wall-bounded flows

The ability of linear stochastic response analysis to estimate coherent motions is investigated in turbulent channel flow at friction Reynolds number Re$_\tau$ = 1007. The analysis is performed for spatial scales characteristic of buffer-layer and large-scale motions by separating the contributions of different temporal frequencies. Good agreement between the measured spatio-temporal power spectral densities and those estimated by means of the resolvent is found when the effect of turbulent Reynolds stresses, modelled with an eddy-viscosity associated to the turbulent mean flow, is included in the resolvent operator. The agreement is further improved when the flat forcing power spectrum (white noise) is replaced with a power spectrum matching the measures. Such a good agreement is not observed when the eddy-viscosity terms are not included in the resolvent operator. In this case, the estimation based on the resolvent is unable to select the right peak frequency and wall-normal location of buffer-layer motions. Similar results are found when comparing truncated expansions of measured streamwise velocity power spectral densities based on a spectral proper orthogonal decomposition to those obtained with optimal resolvent modes

Serre weight conjectures for pp-adic unitary groups of rank 2

We prove a version of the weight part of Serre's conjecture for mod $p$ Galois representations attached to automorphic forms on rank 2 unitary groups which are non-split at $p$. More precisely, let $F/F^+$ denote a CM extension of a totally real field such that every place of $F^+$ above $p$ is unramified and inert in $F$, and let $\overline{r}: \textrm{Gal}(\overline{F^+}/F^+) \longrightarrow {}^C\mathbf{U}_2(\overline{\mathbb{F}}_p)$ be a Galois parameter valued in the $C$-group of a rank 2 unitary group attached to $F/F^+$. We assume that $\overline{r}$ is semisimple and sufficiently generic at all places above $p$. Using base change techniques and (a strengthened version of) the Taylor-Wiles-Kisin conditions, we prove that the set of Serre weights in which $\overline{r}$ is modular agrees with the set of Serre weights predicted by Gee-Herzig-Savitt

HEMODINÂMICA PERIFÉRICA E CENTRAL DE PRATICANTES DE TREINAMENTO RESISTIDO OU AERÓBICO

Objetivos: O presente estudo visou comparar a hemodinâmica central e periférica de indivíduos treinados com exercícios resistidos intensos e corredores de endurance. Métodos: Tonometria de aplanação da artéria radial, velocidade de onda de pulso e medidas ecocardiográficas foram realizadas em 19 indivíduos treinados em exercícios resistidos, 21 corredores de endurance e 29 controles saudáveis destreinados, todos homens, pareados por idade (25 a 50 anos). ANOVA de uma via ou Kruskall Wallis foram usados para a análise dos dados. O teste de comparações múltiplas de Tukey foi utilizado como post-hoc após a ANOVA e o método de Dunn após Kruskall Wallis. Dados expressos como média ± desvio padrão (mediana). Resultados: O índice de incremento corrigido por 75 batimentos por minuto (AIx@75%) foi menor nos indivíduos treinados em exercícios resistidos intensos do que nos corredores de endurance e controles respectivamente [-10,8 ± 10,0 (-15.0)] vs. [-0,6 ± 13,2 (-1.0)] vs. [1,2 ± 12,9 (1.0)], com valor de P <0.001. Corredores de endurance por sua vez apresentaram maior razão de viabilidade subendocárdica (SEVR%) [225 ± 32 (223)] que indivíduos treinados em exercícios resistidos intensos [186 ± 35 (185)] e controles saudáveis [173 ± 27 (174)], com valor de P <0,001. Além disso, corredores de endurance mostraram menor índice de duração de ejeção (ED%) [28 ± 3 (27)] do que indivíduos treinados em exercícios resistidos intensos [32 ± 4 (31)] e controles saudáveis [33 ± 3 (33)], com valor de P <0,001. A velocidade de onda de pulso foi semelhante entre os grupos (P=0,08). Os grupos treinados apresentaram maior massa ventricular esquerda indexada pela superfície corporal (P <0,001). Conclusões: Indivíduos treinados em exercícios resistidos intensos mostraram melhor amortecimento das ondas de pressão enquanto corredores de endurance apresentaram melhor perfusão miocárdica e contração ventricular mais eficiente

Effect of stocking density and protein/fat ratio of the diet on growth of Dover sole (Solea solea)

250 soles (30g initial weight) were randomly placed in 12 experimental tanks at the Discizia's aquaculture marine station. They were reared at 2 different stocking densities (2.3 and 1.3kg/m2 corresponding to 40% and 25% of the bottom surface area covered by fish) and fed on 2 diets with different protein/fat ratio (50% and 54% crude protein and 21% and 18% total lipid, respectively for diets A and B) with triplicate tanks per treatment. The trial lasted 120 days. Fish stocked at the lower density resulted in significantly higher weight gain than fish reared at 2.3 kg/m2 (29.0±7.3 g vs 20.3±8.0g; P<0.01) with a specific growth rate (SGR) of 0.54±0.09 and 0.42±0.13, respectively. Feed conversion rate (FCR) was improved at the lower density (1.8 vs 2.4, P<0.01). The chemical composition of the test diets significantly affected the growth performance of sole. Diet B led to a higher final weight (59.7 vs 50.8g; P<0.01) and better feed utilisation (FCR: 1.8 vs 2.4, P<0.01). These results confirm the necessity to ensure an adequate space for the growing sole and suggest the need for high protein diets to meet sole's requirements