Effects of mechanical agitation and of the addition of grain refiner on the microstructure and mechanical properties of castings of the Al-Sn alloy

The aim of this article was to evaluate the effects of mechanical stirring and grain refiner addition in three different Al-10wt%Sn casting alloys on their resulting macro and microstructures and mechanical properties. These samples were obtained by using: i) die casting, ii) casting with mechanical stirring, iii) die casting using grain refiner (master alloy Al-5wt%Ti-1wt%B) and iv) die casting with grain refiner and mechanical stirring. Experimental results presented different mean grain sizes and different cooling rates when different casting procedures were applied. Cellular and dendritic morphologies were observed when ranges of cooling rates of about 0.6 to 0.75 ºC/s and of 1.75 to 2.55 ºC/s were employed, respectively. Porosity levels of all studied alloy samples were also analyzed. Results of the mechanical behavior, particularly, ultimate tensile strength, yield strength and specific elongation were correlated with mean grain sizes, dendritic arm and cellular spacings and porosity levels attained for the three different cast Al-10wt%Sn alloy samples. The control of the resulting microstructure of the as-cast product may be used as an alternative way to produce sound casting alloy components with improvement in the mechanical properties.O objetivo deste artigo foi avaliar os efeitos da agitação mecânica e de adição de refinador de grão na macro e microestrutura e propriedades mecânicas resultantes de três (03) diferentes procedimentos de fundição utilizando-se de uma liga Al-10%Sn. Os processos de fundição para obtenção das amostras foram: i)fundição por gravidade convencional, ii) fundição por gravidade com agitação mecânica do líquido em resfriamento, iii) fundição por gravidade com adição de refinadores de grão, particularmente adição de 1,5% (em peso) da liga-mãe Al-5%Ti-1%B e iv) fundição por gravidade com adição de refinador de grão e agitação mecânica. Resultados experimentais mostraram que os diferentes procedimentos de fundição propiciaram diferentes valores médios dos tamanhos dos grãos correlacionados com diferentes taxas de resfriamento. Taxas na ordem de 0,60 a 0,75 ºC/s propiciaram microestruturas celulares e taxas na ordem de 1,75 a 2,55 ºC/s resultaram em morfologias dendríticas. Foram avaliados também os níveis de porosidade entre as amostras estudadas. Foram correlacionados os resultados do comportamento mecânico, particularmente, limite de resistência à tração, limite de escoamento e alongamento específico com os tamanhos dos grãos, os espaçamentos dendríticos e celulares e os níveis de porosidade resultantes dos três diferentes procedimentos de obtenção das amostras. Conclui-se que o controle da microestrutura do lingote pode ser usado como um método alternativo para produzir componentes fundidos com melhores resultados de propriedades mecânicas e qualidade dos fundidos.906917Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Contribuição para o estudo da composição e digestibilidade do capim jaraguá (Hiparrhenia Rufa (Nees) Stapf.)

The authors repport in this paper, the results of trials by means of which were determined the composition and nutritive value of Capim Jaraguá, Hyparrhenia rufa (Nees) Stop/, cultivated in Piracicaba, in State of São Paulo, Brazil. The experiments were made with hay, silage and also the grass at three different stages: before, during and after blooming. The digestion trials were carried out with sheep, following the technique of MEAD and GUILBERT. The chemical analysis of the forages were made by methods usually employd. The results are in the table XXIV e XXV of this paper

On the static solutions in gravity with massive scalar field in three dimensions

We investigate circularly symmetric static solutions in three-dimensional gravity with a minimally coupled massive scalar field. We integrate numerically the field equations assuming asymptotic flatness, where black holes do not exist and a naked singularity is present. We also give a brief review on the massless cases with cosmological constant.Comment: 11 pages, LaTeX, 1 Postscript figure. Some changes were don

Novel putative candidate genes associated with umbilical hernia in pigs.

Abstract: Umbilical hernia is one of the most frequent anatomical defects in pigs in which abdominal contents protrude through the umbilical ring. This condition is considered to have a multifactorial basis in which environmental, infectious and genetic factors play a role. However, a better understanding about the genetic components involved in the umbilical hernia development has not yet been achieved. Although a few studies have mapped QTL for umbilical hernia, just a few candidate genes were reported. Therefore, the aim of this study was to identify genomic regions related to the development of umbilical hernias in pigs and search for potential candidate genes. A GWAS was performed with 92 cases and 233 control crossbred pigs. Five SNPs were associated with umbilical hernia: on SSC4/SSC6/SSC13 and one with unknown position. Candidate genes TBX15 and WARS2 were identified close to the SNP on SSC4. Another two candidate genes were located near the SNP associated with umbilical hernia on SSC13 (LIPI and RBM11). Further validation of these genes should be performed to improve the knowledge about umbilical hernia development in order to improve pig welfare and production by eliminating susceptible animals through genetic selection Resumo: A hérnia umbilical é um dos defeitos anatômicos mais freqüentes em suínos nos quais o conteúdo abdominal se projeta através do anel umbilical. Considera-se que esta condição tem uma base multifatorial na qual fatores ambientais, infecciosos e genéticos desempenham um papel. Entretanto, um melhor entendimento sobre os componentes genéticos envolvidos no desenvolvimento da hérnia umbilical ainda não foi alcançado. Embora alguns estudos tenham mapeado o QTL para a hérnia umbilical, apenas alguns genes candidatos foram relatados. Portanto, o objetivo deste estudo foi identificar regiões genômicas relacionadas ao desenvolvimento de hérnias umbilicais em porcos e buscar potenciais genes candidatos. Um GWAS foi realizado com 92 casos e 233 porcos cruzados de controle. Cinco SNPs foram associados com hérnia umbilical: em SSC4 / SSC6 / SSC13 e um com posição desconhecida. Os genes candidatos TBX15 e WARS2 foram identificados próximos ao SNP em SSC4. Outros dois genes candidatos foram localizados perto do SNP associado à hérnia umbilical na SSC13 (LIPI e RBM11). A validação adicional desses genes deve ser realizada para melhorar o conhecimento sobre o desenvolvimento de hérnia umbilical, a fim de melhorar o bem-estar ea produção de suínos, eliminando os animais suscetíveis por meio da seleção genétic

Biomass flow in massai grass fertilized with nitrogen under intermittent stocking grazing with sheep.

Abstract: This study evaluated the biomass flow of massai grass in regrowth subjected to different nitrogen levels (control - no fertilization; 400; 800; and 1200 N kg ha-1year-1) and under rotational stocking with sheep, in a completely randomized design with repeated measures over time. The leaf elongation rate increased with increasing nitrogen levels (N) and the fourth grazing cycle presented a lower value compared with the others. The stem elongation rate responded linearly with increasing levels of N, but it was not influenced by grazing cycles. The senescence rate of leaves remaining before grazing and after grazing were not influenced by the nitrogen fertilization or amended with successive grazing cycles. The phyllochron was influenced only by the nitrogen fertilization, with a decreasing linear response with nitrogen levels. Quadratic response was observed for the average length of leaves with increasing N levels and the grazing cycle 4 presented the lowest value for this variable. For each kilogram N ha-1 year-1, increases of 0.161 and 0.1604 kg ha-1 day-1 were verified in the herbage growth and accumulation rates, respectively. Nitrogen fertilization favors the biomass flow of massai grass, promoting an expressive increase in the production and accumulation of forage

The involvement of muscle-related genes in the occurrence of scrotal hernia in pigs.

Abstract: The incidence of scrotal hernia is still a problem in the swine production, leading to economic losses and reducing the animal welfare. Although some QTLs and candidate genes have already been associated to scrotal hernia, the genetic mechanisms and genes controlling this pathology remain to be clarified. Therefore, this study aimed to identify genes involved in the scrotal hernia occurrence in pigs. Thus, two experiments were performed: 1) RNA-Seq analysis of the inguinal ring tissue from eight 60-days-old Landrace pigs (4 healthy and 4 affected with scrotal hernia) that were sequenced in the Illumina HiSeq 2500 and 2) quantitative PCR (qPCR) of 8 candidate genes chosen from the inguinal ring transcriptome in 18 MS115 30-days-old pigs (9 normal and 9 affected with scrotal hernia). Based on the differentially expressed (DE) genes in this transcriptome, some candidate genes related to muscle development biological processes (BP), including the muscle structure (ACTA1), intracellular transport (RYR1, MYBPC1), cell adhesion (COL13A1) and apoptosis (MAP1LC3) were found. The expression profile of the DE genes was consistent with the anatomical alterations related to the scrotal hernia development, such as the weakness of the inguinal canal and non-obliteration of the processus vaginalis. In the qPCR analysis, the MYH1 was the only DE gene identified. The downregulation of the MYH1gene might be one of the possible causes of scrotal hernia in swine since its expression had already been reduced in 30-days-old affected pigs. Therefore, the DE genes identified in our study related to muscle development bioprocesses are possibly involved in the occurrence of scrotal hernia in pigs. Resumo: A incidência de hérnia escrotal ainda é um problema na produção de suínos, levando a perdas econômicas e reduzindo o bem-estar animal. Embora alguns QTLs e genes candidatos já tenham sido associados à hérnia escrotal, os mecanismos genéticos e os genes que controlam esta patologia ainda precisam ser esclarecidos. Portanto, este estudo teve como objetivo identificar genes envolvidos na ocorrência de hérnia escrotal em suínos. Assim, foram realizadas duas experiências: 1) Análise de RNA-Seq do tecido anelar inguinal de oito suínos Landrace com 60 dias de idade (4 saudáveis ??e 4 afetados com hérnia escrotal) que foram sequenciados no Illumina HiSeq 2500 e 2) PCR quantitativa (qPCR) de 8 genes candidatos escolhidos do transcriptoma do anel inguinal em 18 porcos MS115 com 30 dias de idade (9 normais e 9 afetados com hérnia escrotal). Com base nos genes diferencialmente expressos (DE) neste transcriptoma, alguns genes candidatos relacionaram-se aos processos biológicos (BP) de desenvolvimento muscular, incluindo a estrutura muscular (ACTA1), transporte intracelular (RYR1, MYBPC1), adesão celular (COL13A1) e apoptose ( MAP1LC3) foram encontrados. O perfil de expressão dos genes DE foi consistente com as alterações anatômicas relacionadas ao desenvolvimento da hérnia escrotal, como a fraqueza do canal inguinal e a não obliteração do processo vaginal. Na análise qPCR, o MYH1 foi o único gene DE identificado. O downregulation do gene MYH1 pode ser uma das possíveis causas de hérnia escrotal em suínos, uma vez que sua expressão já havia sido reduzida em suínos afetados com 30 dias de idade. Portanto, os genes DE identificados em nosso estudo relacionados a bioprocessos de desenvolvimento muscular estão possivelmente envolvidos na ocorrência de hérnia escrotal em suínos

SNPs and INDELs in genes involved in lipid metabolism of mammary gland of Zebu breeds identified by whole genome sequencing.

In this context, the objective of this study was to sequence and to map the genome of three Guzerá bulls and three Gir bulls in order to identify zebu-specific variations involved in the lipid metabolism of the mammary gland.ISMB/ECCB 2015. Pôster G28

A striking correspondence between the dynamics generated by the vector fields and by the scalar parabolic equations

The purpose of this paper is to enhance a correspondence between the dynamics of the differential equations $\dot y(t)=g(y(t))$ on $\mathbb{R}^d$ and those of the parabolic equations $\dot u=\Delta u +f(x,u,\nabla u)$ on a bounded domain $\Omega$. We give details on the similarities of these dynamics in the cases $d=1$, $d=2$ and $d\geq 3$ and in the corresponding cases $\Omega=(0,1)$, $\Omega=\mathbb{T}^1$ and dim($\Omega$)$\geq 2$ respectively. In addition to the beauty of such a correspondence, this could serve as a guideline for future research on the dynamics of parabolic equations

Contribuição diagnóstica da ultrassonografia ocular e Doppler Triplex na avaliação de 10 cães Poodle com catarata

Descreveram-se os achados da ultrassonografia ocular convencional e, principalmente, do modo Doppler Triplex na avaliação de 10 cães da raça Poodle com catarata, contribuindo com parâmetros ainda não relatados em medicina veterinária. Foram utilizados 10 cães de diferentes idades e da raça Poodle, apresentando graus variados de catarata. Os animais foram submetidos ao exame oftalmológico e ultrassonográfico. Por meio da ultrassonografia avaliaram-se a anatomia ultrassonográfica dos bulbos oculares e a espessura axial da lente (EAL). Por meio do modo Doppler verificaram-se o tipo de fluxo sanguíneo da artéria oftálmica e seus índices vasculares, a velocidade sistólica (VS), o índice de resistência (RI) e a pulsatividade (PI). Os valores de EAL para olho direito (OD) foi de 5,89±1,05 e para o olho esquerdo (OE) de 6,07±1,32. Por meio do Doppler, observaram-se VS para OD de 26,54±7,05 e VS para OE de 29,21±11,18; PI para OD de 1,89±0,61 e PI para OE de 1,7±0,35; RI para OD de 0,76±0,1 e PI para OE de 0,72±0,09. Concluiu-se que o modo Doppler Triplex mostrou-se importante para determinação das medidas dos índices vasculares da artéria oftálmica, podendo ser utilizada para o acompanhamento de alterações hemodinâmicas nos olhos dos animais acometidos e no acompanhamento da terapia de doenças oculares.The findings of b-mode and especially triplex Doppler ocular ultrasound in the evaluation of 10 Poodle dogs with cataracts, which bring a contribution not yet reported in veterinary medicine, were reported. Ten Poodle dogs of varied ages and presenting cataracts were used. All animals were evaluated for ophthalmic and ultrasound examination. The ultrasound examination allowed the evaluation of the sonographic anatomy of the eye and measurement of the axial thickness of the lens (ATL). Using the Doppler mode, the blood flow of the ophthalmic artery and its vascular indexes, systolic velocity (SV), resistive index (RI) and pulsatility index (PI) were measured. Values found for ATL were 5.89±1.05 for the right eye (OD) and 6.07±1.32 for the left eye (OS). Values found using Doppler evaluation were SV OD: 26.54±7.05 and SV OS: 29.21±11.18; PI OD: 1.89±0.61 and PI OS: 1.7±0.35; RI OD: 0.76±0.1 and RI OS: 0.72±0.09 (OS). It was concluded that triplex Doppler was important for the determination of vascular indexes of the ophthalmic artery, which can be used for monitoring animals with hemodynamic alterations of the eyes and monitoring the therapy of ocular diseases