Comparison of fatigue life behavior between 4-point and uniaxial loading for L-PBF Ti–6Al–4V after HIP treatments

The present study investigated the effects of Hot Isostatic Pressing (HIP) on the fatigue performance of Laser Powder Bed Fusion (L-PBF) Ti–6Al–4V alloy under both 4-point bending and uniaxial testing. Three HIP-cycles were examined: standard, low temperature/high pressure (LTHP), and super beta. Moreover, an annealed heat treatment group was incorporated to compare against the HIP groups. The material microstructure was analyzed and compared across the heat treatments during the study, which showed the presence of α′ martensites, α+β Widmanstätten, and coarse equiaxed grains. Similarly, tensile and hardness testing were implemented to study the mechanical properties, where due to the effects of the HIP treatments, higher ductility but lower hardness values were recorded. Furthermore, fracture morphologies and stress-life (cycles-to-failure) (S–N) curves of the Ti–6Al–4V specimens concerning the fatigue behavior were analyzed. The HIP treatment groups behaved similarly during 4-point bending and uniaxial testing, with the LTHP obtaining a superior fatigue life behavior, followed by the standard and super beta HIP groups. In addition, the efficacy of HIP to reduce pores showed better results in the 4-point bending specimens, leading to few defects as fatigue initiators in contrast to the uniaxial specimens. Fractography results suggested that defects and microstructural features acting as fatigue crack initiators (FCI) govern the fracture behavior of uniaxial specimens. In contrast, only the presence of microstructural features controls the 4-point bending failure behavior

Comunicação intercultural em uma empresa transnacional: a visão dos Brasileiros sobre sua comunicação com os norte-americanos

Cada vez mais a globalização leva as empresas a se comunicarem com culturas diferentes das suas em operações interdependentes. Desta forma, torna-se importante detectar e analisar questões a serem compreendidas pelas organizações na sua comunicação com outras culturas; mais especificamente, aspectos que podem resultar em uma interpretação equivocada das mensagens enviadas de uma cultura para a outra. Para compreender melhor essa questão, foram analisadas as duas atividades simbólicas destacadas por Porter e Samovar (1995) no processo de comunicação verbal - o uso de linguagem e a atividade interna de pensar - à luz das dimensões culturais propostas por Hofstede (1980), Trompenaars (1995) e Hall (1984). Foi realizada uma pesquisa de campo qualitativa de caráter descritivo por meio de entrevistas semiestruturadas na subsidiária localizada na cidade do Rio de Janeiro de uma empresa transnacional de origem norte-americana que atua no setor de telecomunicações. Durante as entrevistas com o diretor e dois gerentes, foram enfatizados alguns pontos negativos na interação entre as duas culturas, mas também foi apontada a possibilidade de captar sinergias da diversidade cultural, como sugerem os bons resultados do estilo relacional dos brasileiros com os clientes e o efeito motivador, nos brasileiros, do tratamento mais igualitário adotado pelos chefes americanos

STRmix™ collaborative exercise on DNA mixture interpretation.

An intra and inter-laboratory study using the probabilistic genotyping (PG) software STRmix™ is reported. Two complex mixtures from the PROVEDIt set, analysed on an Applied Biosystems™ 3500 Series Genetic Analyzer, were selected. 174 participants responded. For Sample 1 (low template, in the order of 200 rfu for major contributors) five participants described the comparison as inconclusive with respect to the POI or excluded him. Where LRs were assigned, the point estimates ranging from 2 × 10 <sup>4</sup> to 8 × 10 <sup>6</sup> . For Sample 2 (in the order of 2000 rfu for major contributors), LRs ranged from 2 × 10 <sup>28</sup> to 2 × 10 <sup>29</sup> . Where LRs were calculated, the differences between participants can be attributed to (from largest to smallest impact): This study demonstrates a high level of repeatability and reproducibility among the participants. For those results that differed from the mode, the differences in LR were almost always minor or conservative

Structural Basis of Pattern Recognition by Innate Immune Molecules

The importance of the innate immune system as a first line defence against pathogenic challenge has long been recognised. Over the last decade the identity of many of the key molecules mediating innate host defence have been clarified and a model of self/nonself discrimination by families of pattern recognition receptors (PRRs) has emerged. Although a large amount of information is now available concerning the action of these innate immune molecules at the level of the cell and organism, little is known about the molecular interface between pathogens and innate immune recognition molecules. In this chapter the molecular basis for innate immune discrimination of a wide variety of pathogen derived molecules is discussed in the context of the emerging literature