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- Author or Editor: A. Sarkar x
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We prove that if 2 2 then the number of paths of length three in a graphGof size m is at most 2m(m - k)(k - 2)=k. Equality is attained if G is the union of Kk and isolated vertices. We also give asymptotically best possible bounds for the maximal number of paths of length s, for arbitrary s, in graphs of size m. Lastly,we discuss the more general problem of maximizing the number of subgraphs isomorphic to a given graph H in graphs of size m.
Grain and malt traits important for malting quality were studied on a set of 131 genotypes including two and six row types barley of indigenous and exotic origin grown at two locations for two seasons. Observations on seven grain and seven malt traits were recorded and malting was done with Phoenix® automatic micro-malting system. The correlation studies indicated that the hot water extract (HWE) is correlated with a number of grain (hectolitre weight, plump %, thin %, protein %, TGW and hull %) and malt (friability, homogeneity, wort viscosity, filtration rate and Kolbach Index) traits either positively or negatively. The multiple regression analysis indicated that hectolitre weight, TGW, hull content and malt friability can be used to predict HWE, the ultimately important trait with malting and brewing industry, in early generations of a breeding programme or for initial screening of germplasm accessions.
Abstract
Magnesium aluminum silicate (MAS) glass samples with different concentrations of alumina (7.58 to 14.71 mol%) were prepared by melt and quench-technique. Total Mg content in the form of MgF2+MgO was kept constant at 25 mol%. MAS glass was converted into glass-ceramics by controlled heat treatment at around 950C. Crystalline phases present in different samples were identified by powder X-ray diffraction technique. Dilatometry technique was used to measure the thermal expansion coefficient and glass transition temperature. Scanning electron microscopy (SEM) was employed to study the microstructure of the glass-ceramic sample. It is seen from X-ray diffraction studies that at low Al2O3 concentrations (up to 10.5 mol%) both MgSiO3 and fluorophlogopite phases are present and at higher Al2O3 concentrations of 12.3 and 14.7 mol%, fluorophlogopite and magnesium silicate (Mg2SiO4), respectively are found as major crystalline phases. The average thermal expansion co-efficient (aavg) of the glass samples decreases systematically from 9.8 to 5.510-6C-1 and the glass transition temperature (T g) increases from 610.1 to 675C with increase in alumina content. However, in glass-ceramic samples the aavg varies in somewhat complex manner from 6.8 to 7.910-6C-1 with variation of Al2O3 content. This was thought to be due to the presence of different crystalline phases, their relative concentration and microstructure.
Abstract
Guidelines for the assessment of internal doses from monitoring suggest default measurement of uncertainties (i.e. lognormal scattering factor, SF) to be used for different types of monitoring data. In this paper, SF values have been evaluated for internal contamination due to 60Co in two cases using whole body counting data. SF values of 1.04 and 1.03 were obtained for case I and II, respectively while SF value of 1.03 was obtained using bioassay data for case I. SF evaluated is in good agreement with the default values given by IDEAS guidelines. The present study also presents the follow up study of a case I of 60Co internal contamination using whole body counting and bioassay analysis. The effect of medical intervention applied on the subject is studied. Medical intervention of d-Penicillamine (250 mg × 4 daily) was orally administered from 13th day of initial exposure for about a fortnight, which showed reduction of activity present by 33.4% through urine.
Abstract
A newly established uranium processing facility has been commissioned at BARC, Trombay. Monitoring of occupational workers is essential to assess intake of uranium in this facility. A group of 21 workers was selected for bioassay monitoring to assess the existing urinary excretion levels of uranium before the commencement of actual work. Bioassay samples collected from these workers were analyzed by ion-exchange technique followed by laser fluorimetry. Standard addition method was followed for estimation of uranium concentration in the samples. The minimum detectable activity by this technique is about 0.2 ng. The range of uranium observed in these samples varies from 19 to 132 ng/L. Few of these samples were also analyzed by fission track analysis technique and the results were found to be comparable to those obtained by laser fluorimetry. The urinary excretion rate observed for the individual can be regarded as a ‘personal baseline’ and will be treated as the existing level of uranium in urine for these workers at the facility.
Abstract
Radish plant was collected along with root and soil from the nearby area of a Municipal Solid Waste dumping site of the metropolitan city of Kolkata, West Bengal, India and analyzed for a wide range of elements using the EDXRF technique with a 109Cd point source and a Si(Li) detector. The samples comprized of the root-soil, root and leaves. For quality control purposes, NIST standard reference material (SRM) 1648 Urban Particulate Matter had also been analyzed using the same procedure as for the samples. Concentrations of elements with X-ray energies in the range of 3–20 keV in the soil around the root and their uptake pattern by the root and the leaves have been estimated.
Abstract
Drinking water samples were collected from four different districts, namely Bhatinda, Mansa, Faridkot and Firozpur, of Punjab for ascertaining the U(nat.) concentrations. All samples were preserved, processed and analyzed by laser fluorimetry (LF). To ensure accuracy of the data obtained by LF, few samples (10 nos) from each district were analyzed by alpha spectrometry as well as by fission track analysis (FTA) technique. For FTA technique few μl of water sample was transferred to polythene tube, lexan detector was immersed in it and the other end of the tube was also heat-sealed. Two samples and one uranium standard were irradiated in DHRUVA reactor. Irradiated detectors were chemically etched and tracks counted using an optical microscope. Uranium concentrations in samples ranged from 3.2 to 60.5 ppb and were comparable with those observed by LF.
Isolates of Pestalozzia theae Saw. and Trichoderma spp. were collected from Bangladesh Tea Research Institute (BTRI) farm area, Bangladesh. The cultural morphology and antagonistic potentiality of Trichoderma spp. against grey blight pathogen Pestalozzia theae was studied for tea cultivation. The antagonistic potentiality of Trichoderma spp., against Pestalozzia theae showed maximum (inhibition 84.45±0.77%) after 72 hrs of inoculation under in vitro condition followed by 76.02±3.50% after 24 hrs of inoculation. This study revealed that Trichoderma strain was highly effective to control Pestalozzia theae, the causal agent of grey blight disease of tea.
