Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration *** components employed in thes...
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Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration *** components employed in these industries are usually obtained by machining,however,these alloys have low machinability when compared to conventional stainless *** this work,a study of the wear developed when milling duplex stainless-steel,LDX 2101,is going to be presented and evaluated,employing four types of milling tools with different geometries and coatings,while studying the influence of feed rate and cutting length in the wear of these *** used have been provided with two and four flutes,as well as three different coatings,namely:TiAlN,TiAlSiN and *** cutting behavior of these tools was analyzed;data relative to the cutting forces developed during the process were obtained;and roughness measurements of the machined surfaces were *** tools were then submitted to scanning electron microscope(SEM)analysis,enabling the identification of the wear mechanisms that tools were subjected to when machining this material,furthermore,the early stages of these mechanisms were also *** this work was done with the goal of relating the machining parameters and cutting force values obtained,identifying,and discussing the wear patterns that were observed in the coating and tools after the milling tests,providing further information on the machining of these alloys.
Background: Human immunodeficiency virus (HIV) type 2 infection is predominantly found in West African nations, and approximately 1 - 2 million people are thought to be infected. HIV-associated nephropathy (HIVAN) occ...
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Background: Human immunodeficiency virus (HIV) type 2 infection is predominantly found in West African nations, and approximately 1 - 2 million people are thought to be infected. HIV-associated nephropathy (HIVAN) occurs in about 7% of patients with HIV-1 infection and is one of the most important causes of end-stage renal disease in this population. The only reported case of HIVAN related to HIV-2 infection was described by Izzedine et al. (2006). Aim: The aim of this paper is to report a case of HIVAN in an HIV-2-infected patient, a rarely described condition. Case presentation: We describe a case of a 40-year-old HIV-2-infected female from Angola hospitalized following a six-month history of fever, fatigue, anorexia and weight loss. Laboratory data revealed anaemia, leukopenia and renal dysfunction with nephrotic range proteinuria. Renal biopsy was performed, revealing findings consistent with HIVAN. Also, a presumed diagnosis of ganglionic tuberculosis was established. Conclusion: The slow progression of HIV-2 disease could explain the low frequency of this condition, however, more studies should be carried out for a better understanding of HIV-2 pathophysiology and its associated complications.
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