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Abstract  

An X-ray fluorescence spectrometric multivariable regression procedure is described for the determination of titanium and molybdenum in special steels and alloys in the concentration range from 9.41% down to 120 μg/g using Ti Kα1,2 and Mo Kα1,2 analyte lines. In general, better results have been achieved in first order base curve polynomials using LiF (200) crystal in combination with scintillation counter (SC) or krypton proportional counter (KPC). However, LiF (220)+SC combination also yields favorable results for Mo. The measured concentrations of Ti and Mo for BAS alloy steel standards agree very well with their certified values. The automated XRFS method for the determination of Ti and Mo appears to be free from matrix effects and is suitable for their measurement in special steels and alloys down to 120 μg/g concentration of Ti with a precision of 3.2% and an accuracy of ±2.5% and for Mo down to 350 μg/g with a precision of <1% and an accuracy of ±1.1%. The sensitivities for these lowest concentrations are calculated to be 5960 counts/mass %/s and 8000 counts/mass %/s for Ti and Mo, respectively.

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Abstract  

Dilute aqueous solution of cresol red has been evaluated spectrophotometrically as possible gamma rays dosimeter. A 0.10 mM solution of cresol red was irradiated by gamma rays using a cobalt-60 radiation source. The absorbance spectra of the unirradiated and irradiated solutions were recorded using double beam scanning spectrophotometer. The absorbance of the solution before and after irradiation was measured at 434 nm (λmax) as well as at other wavelengths (415, 448 and 470 nm). Various parameters, such as Absorbance (A), ΔA, %A, -log A and log Ao/Ai were plotted against radiation dose, in order to check the response of cresol red solution and its possible use as chemical dosimeter. The response plots of A, ΔA, and %A versus absorbed dose showed that the solution can be used as a radiation dosimeter in a dose range up to 0.82 kGy. Using response plots of -log A and log Ao/Ai, the useful dose range can be extended up to 1.65 kGy; which are useful dose ranges for food irradiation applications. Stability studies of cresol red solution at different light and temperature conditions for pre- and post-irradiated storage of the dosimetric solutions suggested that aqueous solution of cresol red is highly stable in dark, under fluorescence light and at room temperature up to 150 days

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I this paper we establish a Riesz representation type theorem which characterizes the dual of the space C rc (X,E)endowed with the countable-ope topologyi the case of E ot ecessarilya locallyconvex TVS.

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Abstract  

Specific activity of natural radionuclides; 226Ra, 232Th and 40K were measured in the agricultural soil of eastern salt range of Pakistan using gamma ray spectrometry. The soil samples were collected within the ploughing region (up to 12 cm depth) and processed before analysis. The average specific activities of different radionuclides in the dry mass of soil samples were: 40K, (666 Bq/kg), 226Ra (51 Bq/kg), and 232Th (59 Bq/kg). The average outdoor terrestrial absorbed dose rate in air from gamma radiation one meter above ground surface was found to be 93 nGy/h.

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A panel of 94 diverse hexaploid wheat accessions was used to map quantitative trait loci (QTL) underlying the yield related traits on chromosome 3A. Population structure and kinships were estimated using unlinked SSR markers from all 21 chromosomes. Analysis of variance revealed significant difference among accessions; however, genotype × year interaction was non-significant for majority of yield related traits. A mixed linear model (MLM) approach identified six QTLs for four traits that individually accounted for 10.7 to 17.3% phenotypic variability. All QTLs were consistently observed for both study years. New putative QTLs for the maximum fertile florets per spike and spike length were identified. This report on QTLs for yield related traits on chromosome 3A will extend the existing knowledge and may prove useful in marker-assisted selection (MAS) for development of high yielding cultivars.

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The allelic variation for Glu-1, Glu-3 loci and presence of IBL-1RS translocation was determined in 126 spring wheat accessions. The most common alleles at Glu-1 loci were Glu-A1b (59.52%), Glu-B1c (41.26%), and Glu-D1d (57.14%) and at Glu-3 loci were Glu-A3c (56.45%), Glu-B3j (29.36%), and Glu-D3b (76.98%). Modern Pakistani wheat varieties carried superior alleles at Glu-1 and Glu-3 loci for bread-making quality and had no negative influence of secalin protein-synthesized by 1BL-1RS translocation. For LMW-GS, the most common combination was Glu-A3c, Glu-B3j and Glu-D3b. The loci Glu-B1 and Glu-B3 had the highest allelic diversity of Glu-1 and Glu-3 loci, respectively.

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Higher plant population and nitrogen management is an adopted approach for improving crop productivity from limited land resources. Moreover, higher plant density and nitrogen regimes may increase the risk of stalk lodging, which is a consequence of complex interplant competition of individual organs. Here, we aimed to investigate the dynamic change in morphology, chemical compositions and lignin promoting enzymes of the second basal inter-nodes altering lodging risk controlled by planting density and nitrogen levels. A field trial was conducted at the Mengcheng research station (33°9′44″N, 116°32′56″E), Huaibei plain, Anhui province, China. A randomized complete block design was adopted, in which four plant densities, i.e., 180, 240, 300, and 360 × 104 ha−1 and four N levels, i.e., 0, 180, 240, and 300 kg ha−1 were studied. The two popular wheat varieties AnNong0711 and YanNong19 were cultivated. Results revealed that the culm lodging resistance (CLRI) index of the second basal internodes was positively and significantly correlated with light interception, lignin and cellulose content. The lignin and cellulose contents were significantly and positive correlated to light interception. The increased planting density and nitrogen levels declined the lignin and its related enzymes activities. The variety AnNong0711 showed more resistive response to lodging compared to YanNong19. Overall our study found that increased planting densities and nitrogen regimes resulted in poor physical strength and enzymatic activity which enhanced lodging risk in wheat varieties. The current study demonstrated that stem bending strength of the basal internode was significantly positive correlated to grains per spike. The thousand grain weight and grain yield had a positive and significant relationship with stem bending strength of the basal internode. The results suggested that the variety YanNong19 produces higher grain yield (9298 kg ha−1) at density 240 × 104 plants ha−1, and 180 kg ha−1 nitrogen, while AnNong0711 produced higher grain yield (10178.86 kg ha−1) at density 240 × 104 plants ha−1 and with 240 kg ha−1 nitrogen. Moreover, this combination of nitrogen and planting density enhanced the grain yield with better lodging resistance.

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The solid-state deaquation of thetrans- andcis-oximates of lawsone (I) and phthiocol (II) with cobalt(II) was investigated by means of non-isothermal thermogravimetry. The modes of deaquation during the thermolyses of hydrated oximates of (I) and (II) with compositions CoL2·2H2O were compared. The weight lossvs. temperature data were treated by using the Coats and Redfern relations. The kinetic data support a rearrangement-type mechanism for the deaquation of the oximate of phthiocol. TheE a values for both the ligands and water molecules were found to be ∼23 kJ/mol.

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European Journal of Microbiology and Immunology
Authors: Abdul Malik Tareen, M. Rafique, A. Wadood, M. Qasim, H. Rahman, S. H. Shah, K. Khan, and G. S. Pirkani

Abstract

Malaria is a serious global health challenge, which is responsible for more than one million deaths a year. Malarial infection is more prevalent in developing countries including Pakistan. Significant efforts have been made to control malaria; however, due to socio-environmental factors, it remains a frequent problem in Quetta. The present study was undertaken to determine the malarial incidence, species prevalence, and its demographic evaluation in human population of Quetta, Pakistan. A total of 1831 subjects, comprising 1072 male and 759 female presenting symptoms of malaria, were included in this study. Blood samples from clinically suspected individuals were subjected to the standard immunochromatographic and malaria parasite smear analysis for malaria diagnosis. Out of 1831 subjects, 338 (18.45%) patients were positive for malarial parasite while the species prevalence was found as 276 (81.66%) and 62 (18.34%) for Plasmodium vivax, and Plasmodium falciparum, respectively. Furthermore, seasonal variations gradual increase in the prevalence rate. The age group of 21–30 years (30.47%) was found more prone to malaria. The suspected malaria cases were found more frequent in rural (72.1%) as compared to urban (27.9%). In addition, the malaria burden was high in urban area (22.89%) population as compared to the rural area (16.74%) population. It was observed that the highest disease occurrence was caused by P. vivax, which reflects a serious threat for public health. The current findings will be helpful to plan effective strategies to prevent and control malaria in this area.

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Cereal Research Communications
Authors: H. Khan, S.C. Bhardwaj, O.P. Gangwar, P. Prasad, P.L. Kashyap, S. Savadi, S. Kumar, and R. Rathore

A set of forty wheat cultivars comprising bread wheat, durum and triticale identified during 2010–2014 were tested for resistance to Indian pathotypes of leaf, stem and yellow rusts at seedling stage under controlled conditions. Eight Lr genes (Lr1, Lr3, Lr10, Lr13, Lr14a, Lr23, Lr24 and Lr26) were characterized based on differential interactions with specific rust races. Genes Lr23, Lr26 and Lr13 conferred leaf rust resistance in most of the accessions. Three Yr genes (YrA, Yr2 and Yr9) were inferred in 40 genotypes, where Yr2 followed by Yr9 were most frequent in conferring stripe rust resistance. Ten Sr genes, namely, Sr2, Sr5, Sr8a, Sr7b, Sr9b, Sr9e, Sr11, Sr13, Sr24 and Sr31, were postulated in these lines with predominance of Sr11, Sr31 and Sr2. These Lr, Sr and Yr genes were observed singly or in combination. Robust DNA markers were used to identify adult plant resistance genes Yr18/Lr34/Sr57, Lr68 and Sr2 and all stage resistance genes Lr24/Sr24, Sr28 and Yr9/Lr26/Sr31. STS marker iag95 showed presence of Yr9 in four additional cultivars which were resistant to one or more rusts. Gene Sr28 was identified in seven durum cultivars with the wPt7004 marker. This is first report of Sr28 being present in many Indian wheat cultivars. CsGs-STS marker identified Lr68 in nine cultivars.

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