Prevalence of transfusion-transmitted virus infection in patients on maintenance hemodialysis from New Delhi, India

Transfusion-transmitted virus (TTV) has been reported from a number of hemodialysis (HD) units from various countries throughout the world. TTV has been associated with liver diseases, viral hepatitis B, and C. Clinical details and information regarding TTV prevalence from India are insufficient. The prevalence and clinical significance of TTV infection were studied in New Delhi, India in HD patients. Serum samples were derived from 75 patients on maintenance HD, and 75 age- and sex-matched voluntary blood donors were examined for TTV viremia by nested polymerase chain reaction (PCR) using primers derived from UTR (A) region of the TTV genome. The prevalence of TTV DNA in patients on HD (83%) was significantly (p<0.05) higher than in blood donors (43%). Clinical background including the mean age, sex, mean duration of HD, and mean alanine aminotransferase (ALT) levels did not differ significantly between TTV DNA-positive and -negative HD patients. Fifty-four (72%) TTV-positive HD patients and 7 (56%) TTV-negative HD patients had blood transfusion histories (p>0.05). Among TTV-positive patients, Hepatitis B virus (HBV) co-infection was present in 14.2% cases while hepatitis C virus (HCV) co-infection was absent. Persistent elevation of ALT levels was observed in 7(9.3%) HD patients; 3 (43%) of them were TTV positive and 4 (57%) were TTV negative (p>0.05). All 3 TTV-positive patients with elevated ALT levels were co-infected with HBV. Patients with TTV infection alone showed normal ALT levels. Prevalence of TTV infection is high in North Indian patients on maintenance HD. Also, none of the exclusively TTV DNA-positive patients had clinical or biochemical signs of liver disease. TTV seems to spread through parenteral routes. More often, TTV seems to be associated with parenterally transmitted virus HBV, indicating a parenteral mode of TTV transmission. The pathogenicity of TTV remains unclear from the present study.     

Interaction of Salmonella enterica subspecies enterica serovar Typhimurium and mung bean (Phaseolus aureus) plants

The effect of Salmonella enterica subspecies enterica serovar Typhimurium, a zoonotic serovar, on mung bean (Phaseolus aureus) cultivar Pant Mung-3 plants was studied. Inoculation of mung bean seeds with Salmonella Typhimurium (7.2 x 10(5) CFU/ml) reduced sprouting rate (P < 0.07). This effect was more pronounced at higher levels of contamination. In the soil inoculated with Salmonella Typhimurium (7.2 x 10(6) CFU/g), germination was retarded and the number of defective sprouts was also significantly higher (P < 0.002). Salmonella Typhimurium grew inside germinating seeds and plant tissues and persisted in seedlings, adult plants, and harvested seedlings dried and stored at room temperature (30 degrees C) up to 45 days. Phaseolus aureus plants grown in sterile soil was resistant to Salmonella Typhimurium infection at 15 days of age and cleared Salmonella from all the aerial parts within 3 h of infection. However, Salmonella Typhimurium could be reisolated from the basal area of the stem and from soil even after 45 days of exposure to the pathogen.     

Combustion of dried animal dung as biofuel results in the generation of highly redox active fine particulates

Background  

The burning of biomass in the developing world for heating and cooking results in high indoor particle concentrations. Long-term exposure to airborne particulate matter (PM) has been associated with increased rates of acute respiratory infections, chronic obstructive lung disease and cancer. In this study we determined the oxidative activity of combustion particles derived from the biomass fuel dung cake by examining their capacity to deplete antioxidants from a model human respiratory tract lining fluid (RTLF). For comparison, the observed oxidative activity was compared with that of particles derived from industrial and vehicular sources.     

Energy use pattern and projections

We examine the potential for energy-conservation for appliance use, technoeconomic systems and social organizations in India.     

A review of three-phase improved power quality AC-DC converters

Three-phase AC-DC converters have been developed to a matured level with improved power quality in terms of power-factor correction, reduced total harmonic distortion at input AC mains, and regulated DC output in buck, boost, buck-boost, multilevel, and multipulse modes with unidirectional and bidirectional power flow. This paper presents an exhaustive review of three-phase improved power quality AC-DC converters (IPQCs) configurations, control strategies, selection of components, comparative factors, recent trends, their suitability, and selection for specific applications. It is aimed at presenting a state of the art on the IPQC technology to researchers, designers, and application engineers dealing with three-phase AC-DC converters. A classified list of around 450 research articles on IPQCs is also appended for a quick reference.     

Radiation exchange and oscillations in a pair of cavaties sharing a partial reflector

Electromagnetic radiation in a system of two optical cavities coupled by a common partial reflector does not equalize between the cavities but oscillates back and forth periodically. Energy transfer between the cavities can be described as a vector rotation in a two-dimensional plane.     

Performance comparison of two-pass modified reverse flat-plate collector with conventional flat-plate collectors

The performance of a modified reverse flat-plate collector with air as working fluid is studied. The results are compared with the corresponding results of a reverse flat-plate collector originally proposed as well as with normal flat-plate collectors operating under single and two pass modes. It is found that much higher fluid temperature can be obtained with the new reverse flat-plate collector.