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Reservoirs and barrages , built across alluvial rivers throughout the world, are losing their storage capacity at an estimated rate of about 1% annually. The pond area of Durgapur Barrage on River Damodar, India, controlled by barrage-gates is no exception. In spite of its service for more than 60 years through judicious gate-operation schedule, it is found that 52% of initial storage capacity Pond has been lost since its inception in 1956. A morphodynamic study of the alluvial Damodar River, extending from Maithon and Panchet dams at upstream to Durgapur Barrage in the downstream, has been done using a numerical model of MIKE-11. Hydrometeorological data of Damodar-Barakar River basin were used to simulate hydrodynamic and sediment transport models for ascertaining annual rate of erosion and deposition during the period 1956–2016. Study shows that about 6 million M3 sediment were transported from catchment through Dam-discharge, a part of which got deposited in the river bed while the remaining 4.9 million M3 washed away downstream through Barrage gates. Although the rate of deposition in the pond area was initially higher during the period 1956–1985, which has subsequently reduced. However, daily deposition increased more or less linearly with the increase in discharge of the river. [ABSTRACT FROM AUTHOR]

An ion chromatography method was developed for the simultaneous determination of fluoride, iodate and iodide in a caustic scrubber solution used for trapping off-gases released during the dissolution of nuclear fuels. A separation between iodate and fluoride could be realized with 0.6 mM hydroxide, which is too weak to elute other anions including iodide in reasonable time. Studies were carried out at different column temperature, and with the help of Van't Hoff plots the thermodynamic parameters associated with the column equilibrium were estimated, which helped in understanding the co-elution of iodate and fluoride at higher concentration of eluent. An arrangement of conductivity detector and UV-VIS detector in sequence after the ion exchange column (with 15 mM NaOH as eluent) was used for recording chromatograms for conductivity signal and UV-VIS signal simultaneously. The information from the two chromatograms was utilized to quantify iodate, fluoride and iodide in a single run. The limit of detection for fluoride, iodate and iodide is 7 ppb, 10 ppb and 12 ppb, respectively. The precision of the method is better than 2% (RSD) at 0.5 mg/L. The method was used successfully for the real sample analysis. [ABSTRACT FROM AUTHOR]

A simple chromatographic method for the determination of trace thorium in uranium matrix has been reported after studying the retention behavior of U(VI) and Th(IV) as their 2,6-pyridine dicarboxylic acid (PDCA) complexes on a reversed phase column. The method does not require pre-separation of uranium matrix. A mobile phase consisting of PDCA, KNO3, and HNO3 in 5% methanol was used. A calibration plot was constructed in the presence of uranium matrix (r2 = 0.9978). The precision of the method is 5% at 1 ppm of Th and LOD was obtained at 0.1 ppm (S/N =3). The accuracy of the method was checked by comparing the results with neutron activation analysis. [ABSTRACT FROM PUBLISHER]

New hockey stick-shaped mesogens with a lateral methyl group inserted between the m-alkyloxy-chain and the azomethine connecting group, 4-(3-n-alkyloxy-2-methyl-phenyliminomethyl) phenyl-4-n-alkyloxycinnamates have been synthesised. The interesting feature of these hockey stick-shaped mesogens is the appearance of the nematic phase in addition to two polymorphic tilted smectic phases - the synclinic smectic C (SmCs) and the anticlinic SmCa phase. Physical characterisation of these mesogens has been carried out using polarising optical microscopy, differential scanning calorimetry, optical birefringence, X-ray diffraction (XRD), electro-optical and dielectric spectroscopy measurements. The SmCs-SmCa phase transition is accompanied by only a small calorimetric signal but causes a pronounced change in the optical textures. Orientational order parameters determined from the birefringence measurements have been compared with those estimated from XRD patterns. Dielectric measurements point to the formation of small 'soft' ferroelectric clusters responsible for a low frequency absorption range. [ABSTRACT FROM AUTHOR]

In this work, we report the results of x-ray diffraction, density and birefringence measurements on three fluorinated liquid crystalline compounds having negative dielectric anisotropy. Small angle x-ray diffraction data from aligned samples have been analyzed to determine the orientational order parameter as a function of temperature. The order parameter values were also determined from birefringence measurements and the results were compared with mean field theory. Structural parameters like intermolecular distance and layer thickness (in smectic B phase), apparent molecular length (in nematic phase) have been determined and the order of the phase transition in these compounds has been discussed. [ABSTRACT FROM AUTHOR]

In this article pool boiling heat transfer coefficient (HTC) of liquids (isopropanol, methanol, and distilled water) on copper-coated heating tubes over a wide range of pressure conditions is computed experimentally. The objective is to find the applicability of soft computing techniques, swarm-intelligence based neural network, and adaptive fuzzy models in the prediction of boiling HTC. The results are compared with those computed experimentally. The performance of models for prediction of HTC is analyzed in terms of root mean square of prediction error. The minimum/maximum value obtained by zero-order fuzzy model with six membership function is 0.0023/3.4383 among all the liquids considered. The model is found to predict HTC with a maximum error of ±0.5% for boiling of liquids over all the coated tubes with pressure varying from atmospheric to subatmospheric levels. The study shows an excellent agreement between the experimental and predicted data. [ABSTRACT FROM AUTHOR]

The aim of this study was to formulate and evaluate microencapsulated controlled release preparations of zidovudine using ethyl cellulose as the retardant material with high entrapment efficiency and extended release. Microspheres were prepared by water-in-oil-in-oil (w/o/o) double emulsion solvent diffusion method. A mixed solvent system (MSS) consisting of acetonitrile and dichloromethane in a 1:1 ratio and light liquid paraffin were chosen as primary and secondary oil phases, respectively. Span 80 was used as the surfactant for stabilizing the secondary oil phase. The prepared microspheres were white, free flowing and spherical in shape and characterized by drug loading, infrared spectroscopy (IR), differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The in vitro release studies were performed using PH 7.4 phosphate buffer. The drug loaded microspheres showed 41–55% of entrapment and release was extended up to 18–20?h. The infrared spectra and DSC and DTA thermograms showed stable character of zidovudine in the drug loaded microspheres and revealed the absence of drug-polymer interactions. SEM studies showed that the microspheres are spherical and porous in nature. Data obtained from in vitro release were fitted to various kinetic models and high correlation was obtained in the Higuchi model. The drug release was found to be diffusion controlled. [ABSTRACT FROM AUTHOR]

The Jarawas are a primitive Negrito tribe of the Andaman islands, India. The members of this tribe have been geographically and socially isolated from the other inhabitants of the islands. None had attended a hospital or health unit until 1997, when a Jarawa boy with a fractured leg was taken to a hospital in Port Blair, and successfully treated. Since then, increasing numbers of Jarawas have sought treatment at the hospital and/or begun to make other contact with non-Jarawas on the islands. No malaria had ever been reported in the tribe until 2001, when an outbreak of febrile illness triggered a malariological survey. Malarial parasites, all identified microscopically as Plasmodium falciparum, were detected in the bloodsmears of 30 of the 179 Jarawas investigated. Although most malaria among the non-Jarawa inhabitants of the islands is caused by P. vivax, only P. falciparum was detected when blood samples from 26 of the subjects were investigated in PCR-based assays. Genetic-diversity studies, based on the msp1 and msp2 polymorphic markers, also revealed a relatively low level of polymorphism in the P. falciparum parasites infecting the Jarawas, compared with that seen in other areas of India. It seems possible that malarial parasites have only recently reached the Jarawas, as the result of the weakening of the tribe's isolation from other humans on the Andaman islands. [ABSTRACT FROM AUTHOR]

A protease isolated from adult Setaria digitata revealed a single, 110-kDa band in a gelatin-impregnated, substrate gel. Analysis with specific inhibitors indicated it to be a metallo-protease. IgG from chronic filarial patients living in an area of Orissa, India, endemic for Wuchereria bancrofti was able to neutralize the proteolytic activity of this enzyme completely. IgG from asymptomatic microfilaraemics and endemic normals (asymptomatic amicrofilaraemics) only caused partial inhibition and IgG from non-endemic normals was ineffective. The generation of inhibitory antibodies appears to depend on the severity of filariasis. Evaluation of IgG-subclass response to the protease indicated the dominance of IgG4 antibodies in asymptomatic carriers and of IgG1 in those with chronic filariasis. The IgG3 response was minimal and the IgG2 responses were similar for each of the filarial groups. When IgG4-subclass serology using the protease antigen was assessed, 47 of 50 microfilaraemics, 20 of 50 endemic normals and 23 of 50 chronic patients but none of 20 non-endemic normals were found seropositive. Appreciable levels of specific IgE, which correlated with those of IgG4, were detected in all filarial groups. IgG4 was detected in 35 out of 70 children (aged <12 years) who appeared amicrofilariaemic and 38 of 40 microfilaraemic children. [ABSTRACT FROM AUTHOR]