Internal avalanches in models of granular media

We study the phenomenon of internal avalanching within the context of recently introduced lattice models of granular media. The avalanche is produced by pulling out a grain at the base of the packing and studying how many grains have to rearrange before the packing is once more stable. We find that the avalanches are long-ranged, decaying as a power-law. We study the distriution of avalanches as a function of the density of the packing and find that the avalanche distribution is a very sensitive structural probe of the system.Comment: 12 pages including 9 eps figures, LaTeX. To appear in Fractal

Speleothems as proxy for the carbon isotope composition of atmospheric CO2

We have measured the stable isotope ratios of carbon in a suite of recent cave deposits (\u3c200 \u3eyears) from the San Saba County, Texas, USA. The methodology for dating these deposits using excess 210Pb was recently established [Baskaran and Iliffe, 1993]. The carbon isotope ratios of these samples, spanning the time period ∼1800–1990 AD, reflect the carbon isotope ratio of atmospheric CO2 for the same period. The pathways by which the δ13C of atmospheric CO2 is imprinted on these speleothems can be explained using a model developed by Cerling (1984). The results suggest that the carbon isotope ratios of speleothems can be used to develop long-term, high-resolution chronologies of the δ13C of atmospheric CO2 and, by implication, the concentration of the atmospheric CO2

Studies on the shedding of Carpospores in Gracilaria corticata J.Ag.

Suto (1950 a, 1950 b) studied the relation between sporulation of seaweeds and seawater temperature. He observed that shedding of tetraspores Started in Gelidium when the seawater temperature rose to 2 0 ' ~ and carpospores to 2 4 ) ~ I Further he observed that there was an optimum temperature range for shedding of spores and abnormal temperature delayed or hastened shedding by about 20 days. Also, he noticed that shedding of monospores of Gelidium amansii increased during calm weather and decreased during rough weather. Segawa et. a1.(1955 a.1955 b)and Jones (1957) studied the nature and mechanism of carpospore liberation in Gracilaria verrucosa (Huds) papenfs. Takeuchi et. a1.(1956) studied the daily output of monospores from cultures of the Conchocelis phase of Porphyra tenera Kjellm. Oza and Krishnamunhy (1968) investigated the carposporic rhythm in Gracilaria verrucosa and reported a peak sporulation of the alga in December and a gradual decline during March - May. In this paper observations on the nature of carpospore output in Gracilaria cortlcata J. Ag. and an estimate of the quantity of spores liberated by the alga during August to December 1969 are presented and discussed

Serum protein profile in patients with pulmonary tuberculosis

A detailed study of the alterations in the serum protein fractions following commencement of effective anti-tuberculosis treatment was undertaken in 511 patients with pulmonary tuberculosis. The concentration of serum albumin was 20-30 per cent higher (P<0.001) and that of a1, a2 and g -globulins significantly lower at the end of treatment than on admission (P <0.01), the magnitude of decrease being 7-17 per cent for g -globulin, 19-30 per cent for a1- globulin and 35-38 per cent for a2- globulin. In all, 481 patients had a favourable response to treatment, 46 of whom had a bacteriological relapse within 18 months of stopping treatment. The likelihood of a relapse was found to be greater with higher a2 -globulin concentrations at the end of treatment, the proportions of patients who relapsed being 3, 9, 13 and 15 per cent with a2 -globulin concentrations of < 0.40, 0.40-0.59, 0.60-0.79 and > 0.80 g/dl (P=0.02)

Uric acid disposition during intermittent chemotherapy of pulmonary tuberculosis with regimens containing pyrazinamide & rifampicin

Uric acid disposition during intermittent chemotherapy of pulmonary tuberculosis was studied in 13 patients allocated to a thrice-weekly regimen containing pyrazinamide in addition to rifampicin, isoniazid and streptomycin and in 19 patients allocated to a twice-weekly regimen of the same four drugs; the dosage of pyrazinam ide was 50 mg/kg in the former and 70 mg/kg in the latter. In the thrice-weekly series, the mean serum uric acid concentration ½ h before drug administration at 2 months (5.5 mg/dl) was significantly higher (P< 0.001) than that on admission (3.2 mg/ dl); hyperuricaemia (>7 mg/dl) was observed in none of the patients on admission and in 3 at 2 months. In the twice-weekly series, the two values (3.4 and 3.1 mg/dl, respectively) were similar, and none of the patients bad hyperuricaemia. The mean concentrations 5 h after drug administration at 2 months were significantly higher (P< 0.001) than those before drug administration in both the series (6.6 and 4.8 mg/dl, respectively), and hyperuricaemia was observed in 4 patients, all in the thrice weekly series

A comparative study of the yield and physical properties of agar-agar from different blends of seaweeds

The agar agar obtained from Gracilaria verrucosa growing in commercial quantities in Chilka Lake, Orissa was found to be having an yield of 23% and gel strength of 41 gm/cm . In order to exploit this agarophyte for the same with other agarophytes like Gelidlella acerosa and Gracilaria edulis in three different proportions was studied

Seaweed culture in India-an appraisal

In recent years there has been a steady increase in the demand for naturally occuring seaweeds as a result of many seaweed based industries coming up. In order to meet the raw material requirement of these industries attempts have been made in this country to develop suitable seaweed farming techniques by some Institutes notably the CMFRI at its Mandepam. Regional Centre and CSMCRI at its field centre, Mandapam. Experimental culture of economically important seaweeds such as Gracllaria edulis, Gelidiella acerosa and other species was undertaken since 1972 at Mandapam- in these experiments production rates ranging from 3 to 8 times the initial wet weight were obtained. The techniques of seaweed culture, the favourable seasons optimum duration of culture period and the influence of environmental parameters are discussed in this account with notes on economics of seaweed culture. General information on the seaweed resources slong our coasts, their potential for exploitation and culture are also highlighted

Studies on removal of chloride from soak liquor

Rice bran is converted into activated charcoal by treating wilh conc. H2S04 and is used as an adsorbent for the removal of chloride present in the tannery soak liquor upto a concentration of 35,000 mgm/litre. It was found to be effetive at the pH. Efrect of the constituents of rice bran on adsorption has also been studied. Infra-red spectra of the samples and the T. L. C. showed that the adsorption is only a physical phenomenon. The rate of adsorption of chloride over the charcoal was determined as 9.150 &#215; 10-3/min. The adsorption passes through triple layer formation as shown by adsorption isotherm. The charcoal removes chloride to the extent of 0.9800 m ep/gm. of the charcoal. The soluble proteins present in the soak liquor are also removed with 100% efficiency. The B. O.D, C.O.D and colour of the soak liquor Were seen to be reduced reduced after passing throuh the charcoal

Alterations in sperm characteristics of follicle-stimulating hormone (FSH)-immunized men are similar to those of FSH-deprived infertile male bonnet monkeys

The quality of sperm ejaculated by bonnet monkeys and normal, healthy proven fertile volunteer men, both actively immunized with ovine follicle-stimulating hormone (oFSH), was examined at different times of study for chromatin packaging and acrosomal glycoprotein concentration by flow cytometry. Susceptibility of sperm nuclear DNA to dithiothreitol (DTT)-induced decondensation, as measured by ethidium bromide binding, was markedly high compared with values at day 0 in men and monkeys during periods when FSH antibody titer was high. Sperm chromatin structure assay yields alphat values, which is another index of chromatin packaging. Higher alphat values, signifying poor packaging, occurred in both species following immunization with heterologous pituitary FSH. The binding of fluorosceinated pisum sativum agglutinin (PSA-FITC) to acrosome of sperm of monkeys and men was significantly low, compared with values at day 0 (control) during periods when cross-reactive FSH antibody titer was high and endogenous FSH was not detectable. Blockade of FSH function in monkeys by active immunization with a recombinant oFSH receptor protein corresponding to a naturally occurring messenger RNA (mRNA) also resulted in production of sperm with similar defects in chromatin packaging and reduced acrosomal glycoprotein concentration. Thus, it appears that in monkeys and men, lack of FSH signaling results in production of sperm that exhibit defective chromatin packaging and reduction in acrosomal glycoprotein content. These characteristics are similar to that exhibited by sperm of some class of infertile men. Interestingly, these alterations in sperm quality occur well ahead of decreased sperm counts in the ejaculate

Some glimpses of the marine fisheries in Andhra pradesh

Andhra Pradesh stands 5th in the marine fish production among the maritime states of India. The advent of mechanisation of fishing craft and introduction of mechanised fishing vessels have brought significant changes in the marine fishing industry of Andhra Pradesh. As a result of this, the fisheries harbour at Visakhapatnam has become one of the key harbours for mechanised trawl fishing and Visakhapatnam itself has emerged as one of the most important centres for exporting marine products to foreign countrie