Análisis Estructural de Tanque Cisterna Semirremolque Fabricado en Aleación de Aluminio para Transporte de Combustibles Líquidos

En este trabajo se estudia el comportamiento estructural de un tanque cisterna semirremolque de aleación de aluminio, fabricado por la firma Tanques Fangio S.A. de la ciudad de Pergamino, provincia de Buenos Aires. Mediante modelización y análisis a través del método de elementos finitos (FEM), se estudia el diseño ‘A’ (modelo clásico), para compararlo luego con un diseño ‘B’ (modelo americano). En ambos casos se estiman los esfuerzos estáticos internos a los cuales se encuentran sometidos los distintos componentes de la estructura del tanque semirremolque, respetando las cargas impuestas por las especificaciones DOT. La modelización, discretización tridimensional y cálculo FEM permiten abordar a los valores de tensiones y deformaciones presentes en ambos modelos. Se concluye que el modelo ‘B’ presenta mejor comportamiento estructural lográndose una mejor relación costo-beneficio

Análisis Estructural de Tanque Cisterna Semirremolque Fabricado en Aleación de Aluminio para Transporte de Combustibles Líquidos

The purpose of this project is to analyze the structural behavior of an aluminum alloy cargo tank, manufactured by Tanques Fangio S.A. This company is located in Pergamino, Buenos Aires, Argentina.Using 3D modeling and FEM (Finite Elements Method) analysis, two kinds of design were studied, the original design called “A” and a new proposal called “B” (American design). In this research, the static loads over the cargo tank structure were calculated using DOT Code.The stress level obtained on this analysis has shown a better structural behavior for the design called “B”, and a higher cost-benefit ratio.En este trabajo se estudia el comportamiento estructural de un tanque cisterna semirremolque de aleación de aluminio, fabricado por la firma Tanques Fangio S.A. de la ciudad de Pergamino, provincia de Buenos Aires. Mediante modelización y análisis a través del método de elementos finitos (FEM), se estudia el diseño ‘A’ (modelo clásico), para compararlo luego con un diseño ‘B’ (modelo americano). En ambos casos se estiman los esfuerzos estáticos internos a los cuales se encuentran sometidos los distintos componentes de la estructura del tanque semirremolque, respetando las cargas impuestas por las especificaciones DOT.La modelización, discretización tridimensional y cálculo FEM permiten abordar a los valores de tensiones y deformaciones presentes en ambos modelos. Se concluye que el modelo ‘B’ presenta mejor comportamiento estructural lográndose una mejor relación costo-beneficio

Genetic Profile of Patients with Limb-Girdle Muscle Weakness in the Chilean Population

Hereditary myopathies are a group of genetically determined muscle disorders comprising more than 300 entities. In Chile, there are no specific registries of the distinct forms of these myopathies. We now report the genetic findings of a series of Chilean patients presenting with limb-girdle muscle weakness of unknown etiology. Eighty-two patients were explored using high-throughput sequencing approaches with neuromuscular gene panels, establishing a definite genetic diagnosis in 49 patients (59.8%) and a highly probable genetic diagnosis in eight additional cases (9.8%). The most frequent causative genes identified were DYSF and CAPN3, accounting for 22% and 8.5% of the cases, respectively, followed by DMD (4.9%) and RYR1 (4.9%). The remaining 17 causative genes were present in one or two cases only. Twelve novel variants were identified. Five patients (6.1%) carried a variant of uncertain significance in genes partially matching the clinical phenotype. Twenty patients (24.4%) did not carry a pathogenic or likely pathogenic variant in the phenotypically related genes, including five patients (6.1%) presenting an autoimmune neuromuscular disorder. The relative frequency of the different forms of myopathy in Chile is like that of other series reported from different regions of the world with perhaps a relatively higher incidence of dysferlinopathy

Genetic connectivity of the ecosystem engineer Perumytilus purpuratus north to the 32ºS southeast Pacific ecological discontinuity

Connectivity in benthic marine animals with complex life cycles occurs primarily during the pelagic lar-val stage and depends deterministically on oceanographic dynamics. The scale of such larval dispersal is highly uncertain due the difficulty of direct measurement and poor knowledge of larval dynamics and ocean flow variability. This study characterizes the pattern of genetic connectivity in the ecosystem engineer Perumytilus purpuratus between latitudes 23°S and 33°S, which includes the ecological discontinuity reported for many taxa north to 32°S at the southeast Pacific. The genetic discontinuity observed in P. purpuratus around 26°S is described herein while that detected at 28°S is in line with the ecological discontinuity (in coverage, recruitment and density) previously reported for this mussel between 28°S and 32°S. Both discontinui-ties delimitate two major gene pools upon Bayesian infer-ences on geographical variation of five microsatellite loci. Interestingly, marker Pepu 1 was responsible for most vari-ation between pools and was potentially under selection. In fact, inferences excluding Pepu 1 produced a single gene pool ( k = 1) in central-northern Chile. The IBD connec-tivity pattern observed among P. purpuratus beds distrib-uted in the interval 23°S–33°S is congruent with processes driven by larval dynamics, and the dominant equatorward Humboldt Current along a coast largely unaffected by ice during the last Pleistocene glaciation. However, the selec-tive scenario unveiled by microsatellite Pepu 1 inside the 25°S–28°S ecological discontinuity is consistent with selective processes associated with specific mesoscale properties operating in this area. This study highlights the usefulness of integrating different oceanographic scales, ecological data and population genetics to better under-stand connectivity of benthic marine species.Versión del editor2,011