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Background and Purpose An alanine to valine exchange at amino acid position 280 (A280V) in the third intracellular loop of the human histamine H

© 2016 IEEE. Impedance-source networks are an increasingly popular solution in power converter applications, especially in single-stage buck-boost power conversion to avoid additional front-end dc-dc power converters. In the survey papers published, no analytical comparisons of different topologies have been described, which makes it difficult to choose the best option. Thus, the aim of this paper is to present a comprehensive analytical comparison of the impedance-source-based buck-boost inverters in terms of passive component count and semiconductor stress. Based on the waveform of the input current, i.e., with or without a transformer, and with or without inductor coupling, the impedance-source converters are classified. The main criterion in our comprehensive comparison is the energy stored in the passive elements, which is considered both under constant and predefined high frequency current ripple in the inductors and the voltage ripple across the capacitors. Two-level and multilevel solutions are described. The conclusions provide a 'one-stop' information source and a selection guide of impedance-source-based buck-boost inverters for different applications.

Elephants, the largest living land mammals, have evolved a specialized foot morphology to help reduce locomotor pressures while supporting their large body mass. Peak pressures that could cause tissue damage are mitigated passively by the anatomy of elephants' feet, yet this mechanism does not seem to work well for some captive animals. This study tests how foot pressures vary among African and Asian elephants from habitats where natural substrates predominate but where foot care protocols differ. Variations in pressure patterns might be related to differences in husbandry, including but not limited to trimming and the substrates that elephants typically stand and move on. Both species' samples exhibited the highest concentration of peak pressures on the lateral digits of their feet (which tend to develop more disease in elephants) and lower pressures around the heel. The trajectories of the foot's centre of pressure were also similar, confirming that when walking at similar speeds, both species load their feet laterally at impact and then shift their weight medially throughout the step until toe-off. Overall, we found evidence of variations in foot pressure patterns that might be attributable to husbandry and other causes, deserving further examination using broader, more comparable samples.

The present work evaluates the corrosion behaviour and the in vitro/in vivo biocompatibility of the AZ31 magnesium alloy, which fulfills the mechanical requirements of bone. The corrosion kinetic of as-received AZ31 alloy was not compatible with the cell growth. To improve its performance, the AZ31 alloy was surface modified by a chemical conversion treatment in hydrofluoric acid. The magnesium fluoride layer generated by the surface treatment of AZ31 alloy enhances its corrosion behaviour, allowing the in vitro growth of osteoblastic cells over the surface and the in vivo formation of a highly compact layer of new bone tissue. These results lead to consider the magnesium fluoride coating as necessary for potential use of the AZ31 alloy as biodegradable and absorbable implant for bone repair.En el presente trabajo se ha estudiado el comportamiento frente a la corrosión y la biocompatibilidad in vitro/in vivo de la aleación de magnesio AZ31, cuyas propiedades mecánicas son superiores a los requisitos mecánicos del hueso. La aleación en estado de recepción ha mostrado una cinética de corrosión no compatible con el crecimiento celular. Para mejorar su comportamiento, el material ha sido modificado superficialmente mediante tratamiento de conversión química en ácido fluorhídrico. La capa de fluoruro de magnesio generada tras este tratamiento mejora el comportamiento del material frente a la corrosión, permitiendo el crecimiento in vitro de células osteoblásticas sobre su superficie y la formación in vivo de una capa de nuevo tejido óseo muy compacta. Estos resultados permiten concluir que el recubrimiento de fluoruro de magnesio es necesario para que el material AZ31 pueda ser potencialmente aplicado como implante biodegradable y reabsorbible en reparaciones óseas.

We have evaluated the local bone response to metallic implants for endoprosthetic implants, over different periods of evolution, from one month to twelve months. The three metallic materials, that have been evaluated, are an alloy of Co-Cr, cpTi, and the MA 956 alloy on whose surface, a layer •-alumina, has been generated by oxidation. The experimental animals used were Wistard rats. The local bone response to the implanted materials, was carried out, using hispathological studies with optical microscopes and the evaluation of the bone/implant interface was studied with a scanning electron microscope (SEM). It was observed that the local bone response in the presence of an implant of titanium or of the alloy MA 956, with an alumina layer, was appropriate and rapid. The differenciation between the fibrous tissue and the bone tissue started from the first stages, at one or three months. This differentiation was definitely consolidated after six months. On the other hand, the local bone response in the presence of Co-Cr was slower, so that after six months the bone response was equivalent to that of the other implants at three months. It was necessary to wait for a year in order to reach a similar bone response among the three materials studied.Se ha evaluado la respuesta ósea local, a implantes metálicos de uso endoprotésico, a distintos tiempos de evolución, desde el mes hasta los doce meses. Los tres materiales metálicos evaluados han sido una aleación de Co-Cr, cpTi, y la aleación MA 956 sobre cuya superficie se ha generado una capa de •-alúmina, por oxidación. Los animales experimentales fueron ratas Wistard. La respuesta ósea a los materiales implantados se llevo a cabo mediante estudios histopatológicos por microscopía óptica, y la evaluación de la interfaz hueso-implante por microscopía electrónica de barrido. Se aprecia que la respuesta ósea local ante la presencia de un implante de titanio o de aleación MA 956, con capa de alúmina, fue adecuada y rápida, comenzando desde las primeras etapas, uno y tres meses, la diferenciación de tejido fibroso a tejido óseo. Esta diferenciación se ve consolidada de forma definitiva al cabo de los seis meses. Por el contrario, la respuesta del organismo ante la presencia de Co-Cr fue más lenta, de modo que a los seis meses la situación era equivalente a la de los otros implantes a los tres meses. Fue preciso esperar un año para alcanzar una situación similar entre los tres materiales estudiados.

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"ABSTRACT: The leader peptide of a recombinant manganese superoxide dismutase (rMnSOD-Lp) acts as a molecular carrier. Clonogenic tests on normal (MRC-5) and endometrial adeno-carcinoma cells (HTB-112) were carried out in the presence of rMnSOD-Lp, cisplatin alone (CC) or cisplatin conjugated to the rMnSOD-Lp (rMnSOD-Lp-CC). The platinum delivered into the cells was measured by atomic spectrophotometric absorbance. The treatments on tumor and normal cells were finally evaluated by LM and TM microscopy. Tumor cell death in the case of 0.5 ¼M cisplatin on its own was minimal, while in the presence of 0.5 ¼M rMnSOD-Lp- CC, no tumor cells survived. Atomic absorbance analysis showed that rMnSOD-Lp-CC delivered approximately 4 times more cisplatin into HTB-112 cells than the amount delivered using cisplatin alone. By LM observation, the cells treated with rMnSOD-Lp-CC showed signs of nuclear and cytoplasmic fragmentation, i.e. apoptosis induced by the treatment. The therapeutic effect of rMnSOD-Lp-CC on endometrial cancer cells was significant, while on the normal cells it showed only a minimal toxicity. We believe that rMnSOD-Lp deserves to be considered as a molecular carrier to deliver cisplatin directly into tumor cells, thus transforming its antireplicative activity into a specific and selective antitumor agent. "

Resumen Introduccion y objetivo El deficit de vitamina D es uno de los principales problemas de la insuficiencia renal cronica. El objetivo del estudio fue comparar los niveles de calcidiol en dialisis peritoneal continua ambulatoria y en hemodialisis, para evaluar si el metodo de dialisis influye en el deficit de vitamina D durante los primeros 4 meses de tratamiento. Pacientes y metodos Se compararon los niveles sericos de calcidiol, calcio y fosforo mediante quimioluminisencia en 31 pacientes diagnosticados con insuficiencia renal cronica, de los cuales 14 recibieron dialisis peritoneal continua ambulatoria y 17 recibieron hemodialisis. Resultados Encontramos mayor disminucion serica del calcidiol en el grupo con dialisis peritoneal, en comparacion con el grupo en hemodialisis, con una significacion estadistica de p Conclusion El procedimiento de dialisis peritoneal puede agravar el deficit de calcidiol en la insuficiencia renal cronica, y probablemente contribuir al incremento de trastornos del metabolismo mineral y favorecer la peritonitis.

Com o objetivo de observar os efeitos do sombreamento propiciado pela tela de polipropileno sobre o comportamento de ovinos da raça Santa Inês em diferentes épocas do ano, montou-se um experimento em Petrolina, PE, no período de junho a novembro de 2010. Utilizaram-se 40 animais distribuídos em igual quantidade em dois tratamentos (Sombreado e Não sombreado) com oferta de pastagem (Tiffton 85) irrigada. Foram feitas aferições dos dados meteorológicos em todas as épocas, com a montagem de termômetros de globo negro e psicrômetros nas duas áreas e de uma mini-estação meteorológica na área sombreada. Nessas épocas foram realizados ensaios de comportamento tendo-se feito observações visuais pelo método da varredura instantânea em intervalos de 10 min no período diurno, verificando-se o percentual de animais quanto à alimentação, ruminação e ócio, a partir da metodologia proposta por Johnson & Combs (1991) adaptada para o tempo de 12 h. O sombreamento não influenciou no número de animais em referência às atividades avaliadas nos diferentes tratamentos. A procura por sombra foi intensa nos períodos mais quentes do dia para a atividade de ócio. Made available in DSpace on 2020-07-08T11:14:07Z (GMT). No. of bitstreams: 1 Comportamento-de-ovinos-da-raca-Santa-Ines-2013.pdf: 523657 bytes, checksum: f70b9a8582d0875749813abb51a60a6f (MD5) Previous issue date: 2013

Apitong (Dipterocarpus spp.) and Caribbean pine (Pinus caribaea Morelet) contain high amounts of extractives that contribute to poor bonding. To reduce, if not to eliminate, the effects of these extraneous substances, surfaces of small wood blocks were Soxhlet-extracted for 8 hours by different solvents. Wettability of the wood surfaces was then measured by droplet and dynamic methods using water and dilute NaOH as liquids. Tensile shear strengths of extracted wood bonded with aqueous vinyl polymer isocyanate (API), resorcinol formaldehyde (RF) and polyvinyl acetate (PVAc) resin adhesives were also measured. Results revealed that although Caribbean pine had much higher resin content than Apitong, the former had better wettability than the latter. Solvent extraction of the adherend with either hexane or ethanol-benzene (1:2) for 8 hours was not enough to improve its wettability but enough to improve its gluability. However, successive extraction with hexane, methanol and ethanol benzene rendered t...

The present work evaluates the corrosion behaviour and the in vitro/in vivo biocompatibility of the AZ31 magnesium alloy, which fulfills the mechanical requirements of bone. The corrosion kinetic of as-received AZ31 alloy was not compatible with the cell growth. To improve its performance, the AZ31 alloy was surface modified by a chemical conversion treatment in hydrofluoric acid. The magnesium fluoride layer generated by the surface treatment of AZ31 alloy enhances its corrosion behaviour, allowing the in vitro growth of osteoblastic cells over the surface and the in vivo formation of a highly compact layer of new bone tissue. These results lead to consider the magnesium fluoride coating as necessary for potential use of the AZ31 alloy as biodegradable and absorbable implant for bone repair. En el presente trabajo se ha estudiado el comportamiento frente a la corrosión y la biocompatibilidad in vitro/in vivo de la aleación de magnesio AZ31, cuyas propiedades mecánicas son superiores a los requisitos mecánicos del hueso. La aleación en estado de recepción ha mostrado una cinética de corrosión no compatible con el crecimiento celular. Para mejorar su comportamiento, el material ha sido modificado superficialmente mediante tratamiento de conversión química en ácido fluorhídrico. La capa de fluoruro de magnesio generada tras este tratamiento mejora el comportamiento del material frente a la corrosión, permitiendo el crecimiento in vitro de células osteoblásticas sobre su superficie y la formación in vivo de una capa de nuevo tejido óseo muy compacta. Estos resultados permiten concluir que el recubrimiento de fluoruro de magnesio es necesario para que el material AZ31 pueda ser potencialmente aplicado como implante biodegradable y reabsorbible en reparaciones óseas.