Generalized integral transform solution for hydrodynamically developing non-Newtonian flows in circular tubes

ABSTRACT: The Generalized Integral Transform Technique (GITT) is applied to the solution of the momentum equations in a hydrodynamically developing laminar flow of a non-Newtonian power-law fluid inside a circular duct. A primitive variables formulation is adopted in order to avoid the singularity of the auxiliary eigenvalue problem in terms of Bessel functions at the centerline of the duct when the GITT approach is applied. Results for the velocity field and friction factor-Reynolds number product are computed for different power-law indices, which are tabulated and graphically presented as functions of the dimensionless coordinates. Critical comparisons with previous results in the literature are also performed, in order to validate the numerical codes developed in the present work and to demonstrate the consistency of the final results.

Volatile and non-volatile compounds and antimicrobial activity of Mansoa difficilis (Cham.) Bureau & K. Schum. (Bignoniaceae)

ABSTRACT: Essential oil from the leaves of Mansoa difficilis was analyzed by GC/MS. Oct-1-en-3-ol (49.65%) was the major compound, but diallyl di- and trisulfide were also present (0.85 and 0.37%, respectively), justifying the garlic-like odor of the crushed leaves. The hexane and methanol extracts of the leaves and stems afforded as main constituents a mixture of linear hydrocarbons, spinasterol, stigmasterol, ursolic and oleanolic acids, two apigenin derivatives and verbascoside. The hexane and methanol extracts of leaves were tested for antimicrobial activity against ten microorganisms. The hexane extract was active against both Psedomonas aeruginosa and Staphylococcus aureus.

Comparison between histopathologic features of leprosy in reaction lesions in HIV coinfected and non-coinfected patients

BACKGROUND: Leprosy and HIV are diseases that have a major impact on public health in Brazil. Patients coinfected with both diseases, appear to be at higher risk to develop leprosy reactions. OBJECTIVE: The aim of this study is to describe the histopathological aspects of cutaneous lesions during reactional states in a group of patients with HIV-leprosy coinfection, compared to patients with leprosy, without coinfection. METHODS: Two groups were established: group 1 comprised of 40 patients coinfected with HIV-leprosy; group 2, comprised of 107 patients with leprosy only. Patients presenting reactional states of leprosy had their lesions biopsied and comparatively evaluated. RESULTS: Reversal reaction was the most frequent feature in both groups, with dermis edema as the most common histopathological finding. Giant cells were seen in all group 1 histopathological examinations. Dermis edema was the most common finding in patients with erythema nodosum leprosum. CONCLUSION: Few histopathological differences were found in both groups, with reversal reaction as the most significant one, although this fact should be analyzed considering the predominant BT clinical form in the coinfected group and BB form in the group without HIV. Larger prospective studies in patients with HIV-leprosy coinfection are needed to confirm and broaden these results.