Molecular weights and conductance studies of some organic poly(aminiumphosphate)s

Summary Long chain poly(aminiumphosphate)s of general composition (BHPO₃)_n (where BH = organic cations) were prepared by precipitation technique. The composition was established by the analysis of these derivatives for N and P. The polymeric nature was confirmed by their molecular weight determinations by end group titration and viscosity methods. Conductance studies at different concentrations confirmed their polyelectrolytic behaviour.     

Effects on spermatogenesis in swiss mice of a protein isolated from the roots of Ricinus communis (Linn.) (Euphorbiaceae)

This study was aimed to evaluate the effect on spermatogenesis of a 62 kDa protein (Rp) isolated from 50% ethanolic extract of the root of Ricinus communis in mice. A dose response study in mice revealed that 25mg/kg body weight/day was the most effective dose. Swiss strain mature male mice of 30 days old were divided into two group namely control and Rp treated (25mg/kg body weight/day). The study showed that sperm motility and count were decreased significantly in the treated group as compared to the control. The fertility index of the treated groups was reduced by 100%. The activity of HMG Co A reductase and cholesterol were increased significantly in the treated group. The testicular activities of 3βHSD, 17βHSD, glucose 6-phosphate dehydrogenase and malic enzyme and the level of serum testosterone were decreased significantly in the treated group. The expression of 3βHSD and 17βHSD were decreased and the expression of StAR increased significantly in the treated group as compared to the control. Proteolytic digestion of the native protein with trypsin and chymotrypsin showed that the proteolytic cleavage did not affect the spermicidal action of Rp. Hence this study can be concluded that Rp impaired spermatogenesis in vivo by suppressing the production of testosterone.     

Removal of viruses from water by sorption on coal

The objective of this research was to investigate the potential of bituminous coal as sorbent for removing viruses from water and to delineate the sorption mechanism(s). This study was undertaken in view of the increasing use of coal in water and wastewater treatment. Bacteriophage T4 against Escherichia coli BB was used as a model virus and coal samples from Neyveli and Giridih were used as sorbents. A sampling method for rapid separation of unsorbed viruses from the sorbent was standardized which consisted of filtering the sample containing coal and viruses through a Whatman filter paper soaked in beef extract. Effects of the following parameters on virus sorption were investigated: pH, ionic strength, temperature, and presence of proteinaceous matter.Maximum virus sorption (about 70%) was observed at pH 8·0 with input virus concentration 1·44 × 10⁴ PFU ml⁻¹, coal size 350 μm and ionic strength 0·02. Optimum ionic strength for virus sorption was found to be 0·015. Higher temperatures increased the sorption capacity and the activation energy was found to be 30·3 kcal/mole. This and low desorption values (6–10%) suggested irreversible chemisorption. Effect of carbon content of coal on sorption-desorption was studied using pure graphite which showed negligible desorption. Effect of proteinaceous matter was investigated using 5% domestic wastewater and the culture broth. Proteinaceous matter appeared to compete with virus for sorption sites on coal and reduced sorption by about 12%.Kinetics and equilibria of sorption on Neyveli coal at pH values 5·5, 7·1 and 8·0 were studied in a non-flow agitated system. Equilibrium sorption was attained in 90 min, the bulk of it being over in 45 min. Sorption data followed Langmuir type isotherm plots and suggested L2 type plot according to Gile's classification (J. Chem. Soc. Part 3, p. 3973, 1960). Isotherm plot with 5% domestic wastewater gave an S curve, suggesting moderate to large intermolecular attraction and implying strong competition for substrate sites from molecules of the solvent. Monomolecular coverage to the extent of only 0·1% of total surface area agreed with the assumptions of isotherm plot and penetration into micropores and macropores of coal was ruled out.     

Urbanisation, poverty and sexual behaviour: the tale of five African cities

The question of how urbanisation and poverty are linked in sub-Saharan Africa is an increasingly pressing one. The urban character of the HIV epidemic in sub-Saharan Africa exacerbates concern about the urbanisation - poverty relationship. Recent empirical work has linked urban poverty, and particularly slum residence, to risky sexual behaviour in Kenya's capital city, Nairobi. This paper explores the generalisability of these assertions about the relationship between urban poverty and sexual behaviour using Demographic and Health Survey data from five African cities: Accra (Ghana), Dar-es-Salaam (Tanzania), Harare (Zimbabwe), Kampala (Uganda) and Nairobi (Kenya). The study affirms that, although risky behaviour varies across the five cities, slum residents demonstrate riskier sexual behaviour compared with non-slum residents. There is earlier sexual debut, lower condom usage and more multiple sexual partners among women residing in slum households regardless of setting, suggesting a relatively uniform effect of urban poverty on sexual risk behaviour.     

Recent Advances in Synthesis of CeVO4 Nanoparticles and Their Potential Scaffold for Photocatalytic Applications

Nowadays, modern nanotechnology has played a crucial role in the diverse domains of science and engineering. In this context, we have summarized the present literature and described the synthetic approaches, structural properties, and diverse potential applications of emerging cerium vanadate nanoparticles (CeVO₄ NPs). Since CeVO₄ NPs are an admirable catalytic, electrical, magnetic, and optical feature, they are used as catalysts, electrodes, sensors, lubricants, solar cells, hydrogen storage devices, and supercapacitors. The effect of diverse factors on the synthesis of CeVO₄ NPs, such as time, temperature, pH, solvent, and concentration, have been successfully discussed and highlighted. Moreover, diverse applications of CeVO₄ NPs, including photocatalysis, sensing, energy storage, and biomedical, have been addressed. Furthermore, a possible perspective for further research on CeVO₄ NPs is also suggested. We firmly believe that this review will be an efficient guide for researchers intrigued by the synthesis and multifunctional applications of CeVO₄ NPs.

     

Effect of Chemicals on the Carbohydrate Contents of Pumpkin (Cucurbita pepo) Seeds During Germination

The effect of pre-soaking treatments of optimum concentration of fertilizers on the carbohydrate contents viz. total sugar, reducing sugars, starch and amylose of Cucurbita pepo (pumpkin) seeds during germination periods up to 12 days were studied. Variations in the contents of carbohydrate during growth periods are explained on the basis of mutual effect of metabolites and of certain related enzymes over and above the effect of method of pre-soaking treatment and of chemicals on the mitochondrial function. It is also reported that the vegetative growth and the nutritive value of mix treatment are higher than in the other cases studied.