609 research outputs found
Functional and morphological assessment of a standardized rat sciatic nerve crush injury with a non-serrated clamp
Peripheral nerve researchers frequently use the rat sciatic nerve crush as a model for axonotmesis.Unfortunately, studies from various research groups report results from different crush techniquesand by using a variety of evaluation tools, making comparisons between studies difficult. The pur-pose of this investigation was to determine the sequence of functional and morphologic changes af-ter an acute sciatic nerve crush injury with a non-serrated clamp, giving a final standardized pres-sure of p9 MPa. Functional recovery was evaluated using the sciatic functional index (SFI), theextensor postural thrust (EPT) and the withdrawal reflex latency (WRL), before injury, and thenat weekly intervals until week 8 postoperatively. The rats were also evaluated preoperatively andat weeks 2, 4, and 8 by ankle kinematics, toe out angle (TOA), and gait-stance duration. In addi-tion, the motor nerve conduction velocity (MNCV) and the gastrocnemius-soleus weight parameterswere measured just before euthanasia. Finally, structural, ultrastructural and histomorphometricanalyses were carried out on regenerated nerve fibers. At 8 weeks after the crush injury, a full func-tional recovery was predicted by SFI, EPT, TOA, and gait-stance duration, while all the other pa-rameters were still recovering their original values. On the other hand, only two of the histomor-phometric parameters of regenerated nerve fibers, namely myelin thickness/axon diameter ratio andfiber/axon diameter ratio, returned to normal values while all other parameters were significantlydifferent from normal values. The employment of traditional methods of functional evaluation inconjunction with the modern techniques of computerized analysis of gait and histomorphometricanalysis should thus be recommended for an overall assessment of recovery in the rat sciatic nervecrush model
Sorovares de Salmonella isolados de humanos no Estado de SĂŁo Paulo, Brasil, 1996-2003
A salmonelose permanece uma importante causa de doença diarrĂ©ica em humanos no Estado de SĂŁo Paulo, Brasil. Nesse estudo foram identificados 3554 isolados de Salmonella de infecções humanas, durante o perĂodo 1996-2003. Entre os 68 diferentes sorovares determinados, S. Enteritidis foi predominante em infecções gastrointestinais e extra-intestinais, responsável por 67.4% de todos os isolados. S. Typhimurium e S. enterica subsp. enterica (4,5,12:i:-) foram mais freqĂĽentemente isolados de crianças com idade de < 1 a 4 anos, em contraste, infecções por S. Enteritidis foram predominantes em pessoas entre 20 e 50 anos. A contĂnua vigilância laboratorial das salmoneloses, incluindo a sorotipagem, tem evidenciado os sorovares de Salmonella causando infecções humanas em nossa área geográfica ao longo do tempo.Salmonellosis remains an important cause of diarrheal illness in humans in SĂŁo Paulo State, Brazil. In this study were identified 3554 Salmonella isolates from human infections, during the period 1996-2003. Among 68 different serovars determined, S. Enteritidis was the most frequent one in gastrointestinal and extra-intestinal infections accounting for 67.4% of all isolates. S. Typhimurium and S. enterica subsp. enterica (4,5,12:i:-) were most frequently isolated from children aged < 1-4 year-old, in contrast, people with S. Enteritidis infections were most likely to be 20-50 year-old. In our geographic area the continued laboratorial surveillance of salmonellosis, including serotyping, has showed the trends in Salmonella serovars causing infections in humans throughout the time
Dirac-like Monopoles in Three Dimensions and Their Possible Influences on the Dynamics of Particles
Dirac-like monopoles are studied in three-dimensional Abelian Maxwell and
Maxwell-Chern-Simons models. Their scalar nature is highlighted and discussed
through a dimensional reduction of four-dimensional electrodynamics with
electric and magnetic sources. Some general properties and similarities of them
when are considered in Minkowski or Euclidian space are mentioned. However, by
virtue of the structure of the space-time in which they are considered a number
of differences among them take place. Furthermore, we pay attention to some
consequences of these objects when acting upon usual particles. Among other
subjects, special attention is given to the study of a Lorentz-violating
non-minimal coupling between neutral fermions and the field generated by a
monopole alone. In addition, an analogue of the Aharonov-Casher effect is
discussed in this framework.Comment: 20 pages. Latex format. No figures. Accepted for publication in Phys.
Rev.
PIRÓLISE DE RESÍDUO DE PETRÓLEO UTILIZANDO MATERIAL MESOPOROSO DO TIPO AL SBA – 15
Os impactos ambientais causados pela indĂşstria do petrĂłleo Ă© um tema em constante discursĂŁo. Neste contexto, se destacam os resĂduos industriais que sĂŁo lançados para o meio ambiente, entre eles a borra oleosa, proveniente da indĂşstria de petrĂłleo.  Considerando o avanço nas pesquisas cientificas e tecnolĂłgicas, com o objetivo de minimizar essa poluição ambiental, a aplicação de materiais catalĂticos Ă© uma alternativa para adicionar a esses resĂduos, visando obter produtos valiosos, como destilados mĂ©dios na faixa dos combustĂveis gasolina e diesel. Neste trabalho, Ă© proposta a aplicação do material catalĂtico mesoporoso do tipo AlSBA-15 adicionado a borra oleosa de petrĂłleo e a aplicação do processo de pirĂłlise, visando a obtenção de hidrocarbonetos de alto valor agregado. A acidez associado com os mesoporos da AlSBA-15 sĂŁo os responsáveis pela atividade e seletividade catalĂtica
Common Proper Motion Search for Faint Companions Around Early-Type Field Stars - Progress Report
The multiplicity of early-type stars is still not well established. The
derived binary fraction is different for individual star forming regions,
suggesting a connection with the age and the environment conditions. The few
studies that have investigated this connection do not provide conclusive
results. To fill in this gap, we started the first detailed
adaptive-optic-assisted imaging survey of early-type field stars to derive
their multiplicity in a homogeneous way. The sample has been extracted from the
Hipparcos Catalog and consists of 341 BA-type stars within ~300 pc from the
Sun. We report the current status of the survey and describe a Monte-Carlo
simulation that estimates the completeness of our companion detection.Comment: 4 pages, 1 figure, conference proc. Syros 200
THERMAL AND OXIDATION STABILITY OF SUNFLOWER METHANOLIC BIODIESEL AND BLENDS OF BIODIESEL/DIESEL
Resumo  A utilização de energias renováveis como o biodiesel tem despertado grande interesse industrial e ambiental. Neste trabalho foram avaliadas as propriedades fĂsico-quĂmicas de diesel, biodiesel, e de suas misturas nas proporções: B5 a B70, atravĂ©s de ensaios de ponto de fulgor, massa especĂfica, viscosidade cinemática. AlĂ©m de estudar a estabilidade tĂ©rmica e oxidativa por TG/DTA. Como resultado foi observado que com o aumento do teor de biodiesel adicionado ao diesel foi observada uma melhoria na sua estabilidade tĂ©rmica e um aumento do resĂduo e atravĂ©s do DTA que misturas que contĂ©m biodiesel sĂŁo mais voláteis que o diesel. Palavras-chave: Biodiesel, Girassol e Termogravimetria.  Abstract  The using of renewable energy like biodiesel has attracted great industrial interest and the environment. In this work we evaluate the physicochemical properties of diesel, biodiesel and their mixtures in proportions: B5 to B70, by testing the flash point, density, kinematic viscosity. Also, thermal and oxidative stability by TGA / DTA. It was verified that by increasing the content of biodiesel added to diesel was observed an improvement in thermal stability and an increase of the residue by DTA and the mixtures containing biodiesel which are more volatile than diesel. Key-words: Biodiesel, Sunflower, Thermogravimetry
Pregnancy rates and clinical outcomes among women living with HIV enrolled in HPTN 052
HPTN 052 was a multi-country clinical trial of cART for preventing heterosexual HIV-1 transmission. The study allowed participation of pregnant women and provided access to cART and contraceptives. We explored associations between pregnancy and clinical measures of HIV disease stage and progression. Of 869 women followed for 5.70 (SD = 1.62) years, 94.7% were married/cohabitating, 96% initiated cART, and 76.3% had >2 past pregnancies. Of 337 women who experienced pregnancy, 89.3% were from countries with lower contraceptive coverage, 56.1% first started cART with PI-based regimens and 57.6% were 25–34 years old. Mean cART duration and condom use were similar among pregnant and nonpregnant individuals. Adjusting for confounders, viral load suppression (VLS) was not (aHR(CI) = 0.82(0.61, 1.08)) and CD4 was slightly associated with decreased rates of first pregnancy over time (aHR(CI) = 0.9(0.84, 0.95)); baseline VLS was associated with increased (aRR(CI) = 2.48(1.71, 3.59)) and baseline CD4 was slightly associated with decreased number of pregnancies (aRR(CI) = 0.9(0.85,0.96)) over study duration. Partner seroconversion was univariably associated with higher rates of first pregnancy (HR(CI) = 2.02(1.32,3.07)). Despite a background of higher maternal morbidity and mortality rates, our findings suggest that becoming pregnant does not pose a threat to maternal health in women with HIV when there is access to medical care and antiretroviral treatment
- …