Sociodemographic and seroprevalence profile of sexually transmitted infections (HIV, Hepatitis B, Hepatitis C and Syphilis) in asymptomatic pregnant females

Background: Globally 499 million new episodes of curable STIs occur in the age group of 15-49 years, 80% in developing countries and 79 million in India alone. There is an increasing trend for viral STIs while bacterial STIs are on decline. Number of pregnant women with STIs is increasing by about 250 million a year in developed world and double that number in developing countries. The objective of the study was to estimate seroprevalence of STIs (Hepatitis C, Hepatitis B, HIV and Syphilis) and to evaluate impact of sociodemographic profile and sexual behaviour on STIsMethods: This observational study was carried out on 1000 asymptomatic pregnant females attending antenatal clinics, Department of Obstetrics and Gynecology, Government Medical College Patiala, Punjab.Results: Seroprevalence for STIs in asymptomatic pregnant females was 22.5%. Hepatitis C-9%, Hepatitis B-6.3%, HIV-5.5%, and Syphilis 1.7%. Illiteracy, low socio economic status, homemakers, rural background with multiple sex partners in the 21-30 years age group is associated with increasing trends of STIs in pregnancy.Conclusions: Screening asymptomatic pregnant women for STIs remains a key programme strategy for quadruple (Hepatitis C, Hepatitis B, HIV and Syphilis) prevention. Mandatory screening for STIs to reduce perinatal transmission is need of the millennium– a step toward ending STI epidemics as a global priority.

Observation of nonlinear bands in near-field scanning optical microscopy of a photonic-crystal waveguide

We have measured the photonic bandstructure of GaAs photonic-crystal waveguides with high energy and momentum resolution using near-field scanning optical microscopy. Intriguingly, we observe additional bands that are not predicted by eigenmode solvers, as was recently demonstrated by Huisman et al. [Phys. Rev. B 86, 155154 (2012)]. We study the presence of these additional bands by performing measurements of these bands while varying the incident light power, revealing a non-linear power dependence. Here, we demonstrate experimentally and theoretically that the observed additional bands are caused by a waveguide-specific near- field tip effect not previously reported, which can significantly phase-modulate the detected field.Comment: 6 pages, 5 figure

Near dispersion-less surface plasmon polariton resonances at a metal-dielectric interface

Omni-directional light coupling to surface plasmon polariton (SPP) modes to make use of plasmon mediated near-field enhancement is challenging. We report possibility of near dispersion-less modes in structures with unpatterned metal-dielectric interfaces having 2-D dielectric patterns on top. We show that the position and dispersion of the excited modes can be controlled by the excitation geometry and the 2-D pattern. The anti-crossings resulting from the in-plane coupling of different SPP modes are also shown.Comment: 15 pages, 4 figure