ABSTRACT
In this work, an effective thermal conductivity (ETC) for living tissues, which directly affects the energy transport process, is determined. The fractal scaling and Monte Carlo methods are used to describe the tissue as a porous medium, and blood is considered a Newtonian and non-Newtonian fluid for comparative and analytical purposes. The effect of the principal variables-such as fractal dimensions DT and Df, porosity, and the power-law index, n-on the temperature profiles as a function of time and tissue depth, for one- and three-layer tissues, besides temperature distribution, are presented. ETC was improved by considering high tissue porosity, low tortuosity, and shear-thinning fluids. In three-layer tissues with different porosities, perfusion with a non-Newtonian fluid contributes to the understanding of the heat transfer process in some parts of the human body.
ABSTRACT
In the present work, an analytical approximate solution of mixed electroosmotic/pressure driven flow of viscoelastic fluids between a parallel plates microchannel is reported. Inserting the Oldroyd, Jaumann, or both time derivatives into the Maxwell model, important differences in the velocity profiles were found. The presence of the shear and normal stresses is only close to the wall. This model can be used as a tool to understand the flow behavior of low viscosity fluids, as most of them experiment on translation, deformation and rotation of the flow. For practical applications, the volumetric flow rate can be controlled with two parameters, namely the gradient pressure and the electrokinetic parameter, once the fluid has been rheologically characterized.
ABSTRACT
In this investigation, the transient electroosmotic flow of multi-layer immiscible viscoelastic fluids in a slit microchannel is studied. Through an appropriate combination of the momentum equation with the rheological model for Maxwell fluids, an hyperbolic partial differential equation is obtained and semi-analytically solved by using the Laplace transform method to describe the velocity field. In the solution process, different electrostatic conditions and electro-viscous stresses have to be considered in the liquid-liquid interfaces due to the transported fluids content buffer solutions based on symmetrical electrolytes. By adopting a dimensionless mathematical model for the governing and constitutive equations, certain dimensionless parameters that control the start-up of electroosmotic flow appear, as the viscosity ratios, dielectric permittivity ratios, the density ratios, the relaxation times, the electrokinetic parameters and the potential differences. In the results, it is shown that the velocity exhibits an oscillatory behavior in the transient regime as a consequence of the competition between the viscous and elastic forces; also, the flow field is affected by the electrostatic conditions at the liquid-liquid interfaces, producing steep velocity gradients, and finally, the time to reach the steady-state is strongly dependent on the relaxation times, viscosity ratios and the number of fluid layers.
ABSTRACT
Alterations in neuroinflammatory processes have been suggested to contribute to the development of Schizophrenia (SZ); one component of the inflammatory system that has been linked to this disorder is interleukin-6 (IL-6). The minor allele of rs2228145, a functional polymorphism in the IL-6 receptor gene, has been associated to elevated IL-6 plasma levels and increased inflammatory activity, making it an interesting candidate to study as a possible factor underlying clinical heterogeneity in SZ. We studied a sample of 100 patients undergoing treatment with clozapine. Their symptoms were quantified by Brief Psychotic Rating Scale; those with the lowest scores ("remitted") were compared with the highest ("clozapine treatment resistant"). We determined allelic frequencies for rs2228145 and IL-6 plasma levels. Our results do not support a role of IL-6 in response to treatment with clozapine. Further studies accounting for potential confounding factors are necessary.
ABSTRACT
El propósito básico de éste documento, es el de "velar"por la limpieza y ornato de la ciudad. La estructura organizativa del Servicio Municipal de Limpieza Pública de la ciudad de La Paz, esta estructurada de la siguiente forma: Servicio de barrido y limpieza de las calles y vías públicas; Recolección y transporte de los deshechos sólidos urbanos para la zona central a cargo de la sección Recolección y Transporte; Las divisiones de Limpieza Urbana, SEMDES-Ciudad y SEMDES-Zona Sur
Subject(s)
Environmental Pollution , Urban Sanitation , Household WorkABSTRACT
El presente documento, pretende mostrar que este manejo, de acuerdo a la experiencia obtenida y la observación reciente en las principales ciudades, es por una parte empírico y por otra deficitaria en la cobertura de sus servicios. Muchos son los factores coyunturales para que tales hechos ocurran; los efectos naturalmente inciden directamente en la contaminación del medio ambiente, por constituirse ésta en el receptor directo de casi el 90
de los desechos producidos por las actividades humanas de estas ciudades
Subject(s)
Environment , Environmental Pollution , Solid Waste , BoliviaABSTRACT
El presente trabajo ha sido preparado por los autores, gracias a la inquietud y auspicios de la Organización Panamericana de la Salud (OPS/OMS), regional Bolivia, dado que el manejo de los desechos domésticos, va cada vez incidiendo en los aspectos sociales y económicos de las poblaciones urbanas bolivianas. Por otra parte, se pretende mostrar que este manejo, de acuerdo a la experiencia obtenida y la observación reciente "in situ" en las principales ciudades (7); es por una parte empírico y por otra deficitaria en la cobertura de sus servicios. Muchos son los factores coyunturales para que tales hechos ocurran; los efectos naturalmente inciden directamente en la contaminación del medio ambiente, por constituirse éste en el receptor directo de casi el 90 por ciento de los desechos producidos por las actividades humanas de estas ciudades
Subject(s)
Environmental Pollution , CongressABSTRACT
los ángulos S.N.P. miden el la clase II 91, 100, 96 grados término medio 95 grados - los ángulos S.N.P. miden en la clase III 92, 92, 100 grados, término medio 94 grados - los ángulos S.N.I. miden en la claseII 83, 90, 87 grados, término medio 91 grados - los ángulos S.N.I. miden en la clase III 89, 89, 97 grados, término medio 91 grados - la radiografía constituye el medio mas adecuado para la determinación de los puntos craneoesféricos - Se establece claramente una diferencia entre los grados obtenidos en este trabajo con referncia a los encontrados en la clase I de angle - la diferncia en grados del ángulo formado por el plano nasión- prostión, nasión-infradentalcorrespondiente a la clase II con relación a la clase III es de 90 grados para la primera y de tercer grado para la segunda