ABSTRACT The rheological behavior of an aqueous suspension of silver nanoparticles stabilized with aminosilane-based surfactant flowing under confinement was investigated. Three stability levels were defined based on the zeta potential: high (41.73 mV, pH 4.3), medium (10.44 mV, pH 7.4), and low (0.74 mV, pH 8.6). Furthermore, the preliminary investigation showed that the surface charge remained positive, and the formation of agglomerates was not observed. Due to the particle coating and the ionization of the amino groups of the surfactant an electrosteric stabilization was evidenced. Shear rates ranging from 50 to 1000 s-1 and shear stresses between 0.02 and 0.2 Pa, at the temperatures of 15, 25 and 35 ºC, were evaluated with the nanofluid flowing in microchannels with a gap of 100, 300 and 500 µm. A trend to dilatant behavior was observed at high shear rate and a slit size of 500 µm, while Newtonian behavior was predominant at lower slit sizes. A reduction of 47.3% was noticed at 25 ºC with the variation in the slit size from 500 to 300 µm. Furthermore, the viscosity of the nanofluid decreased as much as 60% when the slit size was reduced from 500 to 100 µm.

Groups of genes that produce exopolysaccharide with a N-acetyl-D-glucosamine monomer are in the genome of several pathogenic bacteria. Chromobacterium violaceum, an opportunistic pathogen, has the operon hmsHFR-CV2940, whose proteins can synthesize such polysaccharide. In this work, multiple alignments among proteins from bacteria that synthesize such polysaccharide were used to verify the existence of amino acids that might be critical for pathogen activity. Three-dimensional models were generated for spatial visualization of these amino acid residues. The analysis carried out showed that the protein HmsR preserves the amino acids D135, D228, Q264 and R267, considered critical for the formation of biofilms and, furthermore, that these amino acids are close to each other. The protein HmsF of C. violaceum preserves the residues D86, D87, H156 and W115. It was also shown that these residues are also close to each other in their spatial arrangement. For the proteins HmsH and CV2940 there is evidence of conservation of the residues R104 and W94, respectively. Conservation and favorable spatial location of those critical amino acids that constitute the proteins of the operon indicates that they preserve the same enzymatic function in biofilm synthesis. This is an indicator that the operon hmsHFR-CV2940 is a possible target in C. violaceum pathogenicity.

This is a qualitative study to understand the activities carried out by managers of basic health care units in Belo Horizonte, State of Minas Gerais, Brazil. The data collected by interview underwent discourse analysis and were divided into two categories. We found that the activities of the day-to-day work of the managers mix with those of basic qualification. Managers have learned to work with a lack of resources, but feel rewarded with the responses they manage to give to the community. They have had to work facing new demands which require skills that go beyond the technical and administrative in order to provide a more humanized care.

El objetivo del presente estudio es comprender las actividades de los gerentes que trabajan en las Unidades Básicas de Salud de Belo Horizonte. Los datos, obtenidos por medio de entrevista, fueron sometidos al análisis del discurso y se organizaron en dos categorías. Revelan que las actividades inherentes a lo cotidiano de la gerencia se confunden con aquéllas propias de la formación básica. El gerente está aprendiendo a trabajar con la falta de recursos y se siente recompensado con las respuestas que logra dar a la comunidad. La gerencia incorpora una gestión delineada por nuevas demandas que exigen, además de habilidades técnico-administrativas, otras que buscan una asistencia más humanizada.

Estudo qualitativo com objetivo de compreender as atividades desempenhadas pelos gerentes que atuam em UBS de Belo Horizonte. Os dados coletados por entrevista, foram submetidos à análise de discurso e organizados em duas categorias. Revela-se que as atividades inerentes ao cotidiano da gerência se confundem com aquelas próprias da formação básica. O gerente vem aprendendo a trabalhar com a escassez de recursos, mas se sente recompensado com as respostas que consegue dar à comunidade. A gerência incorpora uma gestão delineada por novas demandas que exigem habilidades que vão além das técnico-administrativas em busca de uma assistência mais humanizada.