Beryllium: an easily scavenged metal ion in the environment

This study was specifically aimed to determine the levels of beryllium in environmental samples near the vicinity of the beryllium metal plant (BMP). Air particulate samples collected at the BMP site, in the non-monsoon and monsoon seasons, showed an average beryllium concentration of 0.3 and 0.1 ng m(-3) respectively, where as rain water samples showed the beryllium values in the range of 0.01-0.2 ng ml(-1). The suspended particulate matter (dust load) at the site studied was 570 and 250 microg m(-3) in the non-monsoon and monsoon seasons respectively. The results obtained show that, in the environment, 80% of the total beryllium present is removed by rain.

Immobilisation of beryllium in solid waste (red-mud) by fixation and vitrification

The objective of this study was to obtain information on the immobilization of beryllium (Be) in solid waste generated in the extraction process of beryllium from its ore, Beryl. This solid waste, termed red-mud, contains oxides of iron, aluminium, calcium, magnesium and beryllium. The red-mud waste contains beryllium at levels above the permissible limit, which prevents its disposal as solid waste. The total beryllium content in the red-mud analysed showed value ranging from 0.39 to 0.59% Be The studies showed that 50% of the total beryllium in red-mud can be extracted by water by repeated leaching over a period of 45 days. The cement mix, casting into cement blocks, was subjected to leachability studies over a period of 105 days and immobilization factor (IF factor) was determined. These IF values, of the order of 102, were compared with those obtained by performing leachability study on vitrified red-mud masses produced at different temperature conditions. Direct heating of the red-mud gave the gray coloured, non-transparent vitreous mass (as 'bad glass') showed effective immobilisation factor for beryllium in red-mud of the order of 10(4).

Factors influencing continuation of IUD use in south India: evidence from a multivariate analysis

This paper studies the correlates of IUD continuation, particularly in relation to quality of service provided in Karnataka, South India, by using a discrete-time logit model. Provision of follow-up services had a moderate influence on continuation, and medical check-up at insertion influenced the experience of side effects. But these effects were trivial in comparison with the overriding influence of motivational variables and of reported side effects. The IUD is retained for a limited duration in rural India where it is used mainly as a spacing device by lowly motivated young women who discontinue the method at the slightest feeling of discomfort or abnormality. If the IUD were recommended to older women for limiting childbearing by emphasizing its reversibility, it would enhance the method's popularity and improve the levels of contraceptive use among younger women.

Maternal mortality in India: estimates from a regression model

This report outlines a new technique for the estimation of maternal mortality by relating the sex differentials in mortality for people of reproductive age to the age schedule of fertility. The application of this method to the data from the Sample Registration System for 1982-86 indicates a level of maternal mortality of 580 deaths per 100,000 live births for India as a whole, 638 deaths in rural areas, and 389 deaths in urban areas. Estimates derived for the major states suggest relatively high maternal mortality in the eastern and northern parts of the country. They also indicate a substantial decline in maternal mortality since the 1960s. The decline in the birth rate is estimated to have accounted for nearly one-fourth of the decrease in the maternal death rate and 5 percent of the fall in the maternal mortality ratio in the 10-year period between 1972-76 and 1982-86. The method of estimation described here is well-suited to the data circumstances in India.

The principles and practice of rinderpest eradication

Rinderpest can be controlled by interrupting its transmission. This objective can be achieved by implementing zoo sanitary controls to eliminate or reduce the excretion of virus or by the use of vaccine to prevent the infection of fresh hosts. For success in the eradication of rinderpest these two techniques must be combined and used within time-bound campaign frameworks. The tools required for implementing rinderpest eradication are legal powers to declare farms to be infected premises and their surroundings to be infected areas, along with a cheap and efficacious vaccine. Finally, before embarking on rinderpest eradication an epidemiologically valid strategy must be adopted, financed and placed under competent management.

Single-step bulk purification of synthetic tetrapeptide tuftsin by high performance liquid chromatography

A protocol on reversed phase high performance liquid chromatogrpahy (RP-HPLC) using water-acetonitrile gradients under lesser stringent conditions, has been devised to obtain highly purified tuftsin in bulk amount. The protocol was also tested for two different preparations of tuftsin to yield identical quality of peptide.

Conformation of a T-cell stimulating peptide of interleukin-1 beta protein: circular dichroism studies

A T-cell stimulating peptide Val-Gln-Gly-Glu-Glu-Ser-Asn-Asp-Lys-OH, the 163-171 fragment epitope of interleukin-1 beta (IL-1 beta), has been synthesized in solution phase and purified by reverse-phase high-performance liquid chromatography (RP-HPLC). The backbone conformation of the synthetic fragment, investigated in aqueous solution by circular dichroism (CD) spectroscopy, is qualitatively a mixture of beta-turns and random coil. Quantification of the CD spectra revealed the presence of a 9% beta-turn fraction in water at pH 7.0, suggesting the occurrence of the conformation for the epitope fragment in aqueous solution necessary for T-cell stimulation and antigenicity. Concomitant changes in CD spectra were observed with increases in the trifluoroethanol (TFE) concentration in water, and the beta-turn fraction in peptide increased to 28% at a concentration of 90% TFE. This helicogenic solvent, as well as other solvents such as methanol, acetonitrile and dioxane (all favouring an ordered structure in peptides), failed to induce any alpha-helical conformation in the IL-1 beta (163-171) fragment, and CD spectra were attributed to only beta-turn ordered structure. This beta-turn structure has also been found to be a theoretically preferred conformation using Chou-Fasman proclivity data and is in accordance with the presence of an all-beta-globular conformation for its parent molecule IL-1 beta. Thus, the beta-turn conformation is probably involved in retention of T-cell stimulation activity in this synthetic epitope.

Discovery of Intense Gamma-Ray Flashes of Atmospheric Origin

Detectors aboard the Compton Gamma Ray Observatory have observed an unexplained terrestrial phenomenon: brief, intense flashes of gamma rays. These flashes must originate in the atmosphere at altitudes above at least 30 kilometers in order to escape atmospheric absorption and reach the orbiting detectors. At least a dozen such events have been detected over the past 2 years. The photon spectra from the events are very hard (peaking in the high-energy portion of the spectrum) and are consistent with bremsstrahlung emission from energetic (million-electron volt) electrons. The most likely origin of these high-energy electrons, although speculative at this time, is a rare type of high-altitude electrical discharge above thunderstorm regions.

Priority areas in demographic research

"This paper reviews...demographic development [in India] since the mid-1970s and highlights important data gaps in respect to (i) fertility and family planning (ii) mortality and morbidity along with priority areas for exploratory research. The paper notes that during the past two decades, [the] demographic data-base in India has improved considerably. Fertility levels have begun to fall in many places and mortality has continued its rapid downward course...."

Identification and size variation of terminal fragments of sheep pox virus genome

Terminal fragments of sheep pox virus DNA identified by snap-back analysis showed terminal covalent cross-links. Southern blot hybridization using a terminal fragment probe confirmed the termini and terminal repeats (common sequences) of the sheep pox virus genome. Terminal fragment length variability was observed between virus isolates.

Recent trends in age-specific mortality in India

"In this paper we have analyzed the data from the Sample Registration System [SRS] on mortality by age and sex [in India] since 1970. Some of the major conclusions emerging from this analysis are: (i) Mortality has declined more rapidly among infants, children under 15 years and women of reproductive ages....(ii) Among adults, mortality has declined more rapidly among females than among males, the differential gain being largest in the age span 25-49. But in ages under 15, there is no evidence to suggest a gender differential in mortality decline. (iii) Among children and women of reproductive ages, mortality has declined more rapidly in urban areas than in rural areas but the reverse is true in the case of adult men.... The paper also analyzes the trends in mortality in major states of India during 1970-86." The authors observe a significant shift in patterns between 1978 and 1979, and conclude that this may be limited to changes in SRS data collection techniques.

Estimating transition probabilities of age misstatement

This article outlines a method of estimating probabilities of gross transfers from one age to another due to misreporting of age. An essential ingredient in the computation is the information on the true age structure of the population, which may be estimated by using generalized stable population relationships. The method consists essentially of iteratively adjusting rows and columns of an initial guess matrix so that the application of the resultant transition matrix to the true age distribution produces the recorded age distribution. The initial guess matrix can be either empirically based or theoretically derived. The method is illustrated by using data on India, 1971-1981. The application reveals that in India, although the tendency to exaggerate age is strong at adult ages, the bias does not increase appreciably at older ages, as is commonly believed.

Genetic divergence in various Sahiwal x Holstein crossbred grades

The degree of genetic divergence using Mahalanobis's D(2) statistic and the clustering pattern using canonical variate analysis between Sahiwal and its 39 Friesian grades were studied for 9 characters of economic importance. The records were adjusted for the significant effects due to farms, periods and seasons. Forty grades were grouped into 11 clusters. The results have shown that in cattle when two breeds of diverse origin, one of superior merit and the other relatively inferior, are crossed in a scheme of forward crossing, there is no linear increase in production level above 50% with the increase in genes of the superior parent. It can not be assumed that grading up to a total replacement of genes will lead to higher levels of production at least in cattle. In order to stabilize a breed type from such a crossbred population a breeding plan has been proposed.