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An interpolative-based first-order maximum entropy (M1) moment closure for providing approximate solutions to the equation of radiative transfer in non-gray participating media is proposed and described. This newly developed non-gray moment closure technique results in significant computational savings compared to an approach that makes use of the direct numerical solution of the optimization problem for entropy maximization. Its predictive capabilities are also assessed by comparing its solutions to those of the more commonly adopted first-order spherical harmonics (P1) moment closure technique, as well as the popular discrete ordinates method (DOM), which is used as a benchmark for the model comparisons. The evaluations are performed for sooting co-flow laminar diffusion flames for blends of ethanol and methane fuels at atmospheric as well as at elevated pressures and include comparisons to available experimental data for soot volume fraction and flame temperature. The strong spectral dependence exhibited by the absorption coefficient of real gases is treated herein using the statistical narrow-band correlated-k method, and the chemical kinetics of the underlying species are modeled using a reduced mechanism for methane and ethanol fuels. Theoretical details of the proposed interpolative M1, along with a description of the proposed Godunov-type finite-volume scheme developed for the numerical solution of the resulting system of hyperbolic moment equations are briefly discussed. The finite-volume method makes use of limited second-order solution reconstruction, multi-block body-fitted quadrilateral meshes with anisotropic adaptive mesh refinement (AMR), and an efficient Newton–Krylov–Schwarz (NKS) iterative method for solution of the resulting nonlinear algebraic equations arising from the finite-volume discretization procedure. The numerical results for laminar co-flow flames show that the flame solutions and predictions of soot formation of the non-gray M1 maximum-entropy moment closure are very promising and in very good agreement with those of both the DOM and P1 spherical harmonics model, while offering a substantial reduction in the number of dependent solution variables, compared to the DOM. [ABSTRACT FROM AUTHOR]

Numerical study of the 2-D heat transfer stimulated by free laminar convection in an enclosure reveals that the stream function of heat flow consists of a two-cellular flow pattern. The pattern is symmetric to the vertical axis which has a positive counterclockwise and negative clockwise eddy. A four-cellular flow is observed when the heat flux is applied to inner cylinder at very high magnitudes.

The purpose of this study was to conduct a cohort analysis six years after the introduction of medical care for HIV-infected patients in the first voluntary and anonymous screening center in Senegal. This paper provides a retrospective descriptive study of the medical records of HIV-infected patients followed between 2004 and 2009. The center provided care to 389 patients over the course of the six-year period. The median age of patients was 36 years [17- 69 years], with a sex-ratio (F/M) of 2.5. Access to care was mainly by voluntary screening (313 cases). Two thirds (65%) of patients were either asymptomatic or pauci-symptomatic (WHO Stage I/II). Prurigo (20%) and sexually transmitted infections (19%) were the main diseases diagnosed among patients. 66.6% of patients had a CD4+ cell count ? 200/mm3. By the end of 2009, two hundred and thirty-five patients were still being followed. The rate of patients lost to follow-up was 29%, while the lethality rate was 6%. The assessment of the activities of the voluntary, anonymous and free screening center shows the importance of screening centers in the fight to promote knowledge about HIV infection.

Rinderpest is an acute and highly contagious viral disease of ruminants, often resulting in greater than 90% mortality. We previously reported the development of first- and second-generation recombinant vaccinia virus vaccines which provide complete protection against rinderpest virus (RPV) and peste-des-petits ruminants virus (PPRV). These vaccines are safe even for immunodeficient mice and macaques with acquired immunodeficiency syndrome. We developed a third-generation recombinant vaccinia virus vaccine (v2RVFH) that expresses the fusion and haemagglutinin genes of RPV under strong synthetic vaccinia virus promoters. Cattle vaccinated intramuscularly with as little as 10(3) plaque-forming units (PFU) of v2RVFH were completely protected from rinderpest. Vaccinated animals did not develop pock lesions or transmit v2RVFH to contact animals. Cattle vaccinated with a standard dose of 10(8) PFU of v2RVFH developed long-term, sterilizing immunity against rinderpest. Thus, v2RVFH is safe, efficacious, heat stable, inexpensive, easily administered, and allows serological differentiation between vaccinated and infected animals. To aid in diagnosis and differentiation of vaccinated from infected animals, we developed indirect ELISAs (iELISAs) that use baculovirus-expressed RPV or PPRV nucleoprotein as coating antigens. A single larva contains enough viral antigen to test more than 10,000 serum samples, in duplicate. African scientists trained at the ILMB successfully transferred the iELISA kit technology to more than 30 countries in Africa, providing a model for technology transfer among developing countries. Vaccination with v2RVFH, in conjunction with the iELISA kits, greatly enhances the prospects for global eradication of rinderpest, as developing nations achieve independence in control efforts.

From 1986 to 1988 a sero-epidemiological survey was carried out in Mali by ILCA to identify the small ruminant main respiratory viruses. The results of this investigation shows an endemic condition. Regardless of the virus species involved, neutralizing antibodies were detected in adults as well as in young stocks. New researches are necessary to set forth a consistent and effective policy of prophylaxis or treatment according to the case concerned.