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Abstract
Production of Copper-64 (64Cu) by irradiating copper and zinc metals in a reactor was evaluated. Low specific activity 64Cu can be easily produced using thermal neutrons via 63Cu (n,γ) 64Cu reaction, while use of fast neutrons are mandatory for high specific activity 64Cu via 64Zn (n,p) 64Cu reaction. Natural copper and zinc targets were irradiated in Pakistan Research Reactor-1. Radionuclidic impurities produced by thermal and fast neutrons were determined. Commonly available organic anion exchange resin (AG 1-X8) was used for the separation of no-carrier-added radiocopper from neutron irradiated zinc. More than 95% 64,67Cu was recovered. The radionuclidic and chemical purity of 64Cu was determined. The specific activity of 64Cu produced by 63Cu (n,γ) and 64Zn (n,p) was compared.
A total of 32 bacterial isolates including Mesorhizobium (N=10), Azotobacter (N=12) and phosphate-solubilizing bacteria (N=10) were isolated and tested for siderophore, HCN, ammonia, indole acetic acid production and phosphate solubilization in vitro . The bacterial cultures were positive for siderophore, HCN and ammonia. Among the isolates, M. ciceri RC3 and A. chrococcum A4 displayed 35 and 14 μg ml −1 of IAA, respectively, whereas Bacillus produced 19 ( Bacillus PSB1) and 17 μg ml −1 ( Bacillus PSB10) of IAA in Luria Bertani broth. The diameter of the P solubilization zone varied between 4 ( Bacillus PSB1) and 5 mm ( Bacillus PSB10) and a considerable amount of tricalcium phosphate (7 and 8 μg ml −1 by Bacillus PSB1 and Bacillus PSB10, respectively) was released in liquid medium, with a concomitant drop in pH. The effects of N 2 -fixing and PS bacteria on the growth, chlorophyll content, seed yield, grain protein and N uptake of chickpea plants in field trials varied considerably between the treatments. Nodule number and biomass were significantly greater at 90 days after sowing (DAS), decreasing by 145 DAS. Seed yield increased by 250% due to inoculation with M. ciceri RC3 + A. chroococcum A4 + Bacillus PSB10, relative to the control treatment. Grain protein content ranged from 180 ( Bacillus PSB1) to 309 ng g −1 ( M. ciceri RC3 + A. chroococcum A4 + Bacillus PSB10) in inoculated chickpea. The N contents in roots and shoots differed considerably among the treatments.
Effects of fly ash amendments in soil (0%, 25% and 50% vol/vol), Ralstonia solanacearum, Meloidogyne incognita and Phomopsis vexans were observed on the growth, chlorophyll and carotenoid contents of eggplant. Addition of 25% fly ash in soil caused a significant increase in plant growth, chlorophyll and carotenoid contents over plants grown without fly ash. However, amendments of 50% fly ash in soil had an adverse effect on the growth, chlorophyll and carotenoid contents of eggplant. Inoculation of the pathogens caused a significant reduction in growth, chlorophyll and carotenoid contents. Inoculation of R. solanacearum caused the greatest reduction followed by P. vexans and M. incognita. Root galling and nematode multiplication was reduced with the increase in fly ash. Wilting and blight indices were 3 in plants grown in 0% and 25% fly ash amended soil while 4 in 50% fly ash amended soil.
Abstract
An investigation on the level of some minor and trace elements in some varieties of meat (beef, mutton and chicken) consumed in Bangladesh is reported. In this study, protoninduced X-ray emission (PIXE) and radioisotope-induced X-ray fluorescence (XRF) techniques were used for analytical measurements. In PIXE measurements, the samples were exposed to the proton beam in air as 1 mm thick pellets and irradiated with 2.0 MeV protons having the beam intensity of 30 nA for characteristic X-ray excitation, whereas in XRF, the samples were excited for 5000 seconds with a 10 mCi109Cd annular X-ray source. The elemental concentrations of Ca, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb and Sr were determined in the samples by comparison with X-ray yield curves constructed from IAEA and NBS standard reference materials. The significance of the results is dicussed in relation to human health and diseases.
Abstract
The trace element concentrations of eight elements (Ca, Cr, Mn, Fe, Ni, Cu, Zn and Pb) in the scalp hair of 49 normal and 55 malnourished children of the Bangladesh population, in the age group of 1 to 5 years were analyzed by the external beam PIXE method to establish their baseline values in normal children for pre-diagnostic screening of deficiency and excess in malnutrition. The results of this investigation show that the ranges of trace elements in hair are somewhat wide. For example, the normal Zn level has the range of 63–377 
g·g–1 for 49 subjects. The reasons for these large individual deviations are unknown till now. The average of the elemental concentrations between normal and malnourished groups are compared (t-test,p<0.05). A correlation study has been done on each pair of original data by a non-parametric Speaman's rank test. The frequency distributions of the elements are presented and the results are compared with the data reported in the literature. A substantive correspondence between the present data in hair of both the study groups and the literature values from different countries have been observed but they did not show any regular dependence on the nutritional status of the subjects. Only the low Cu content in the hair of malnourished group can possibly be linked with nutritional disorders as evidenced from this study.
Cognitive impairment is a common feature of both lead exposure and hyperphosphorylation of tau. We, therefore, investigated whether lead exposure would induce tau hyperphosphorylation. Wistar rat pups were exposed to 0.2% lead acetate via their dams’ drinking water from postnatal day 1 to 21. Lead in blood and brain were measured by atomic absorption spectrophotometry and the expression of tau, phosphorylated tau and various serine/threonine protein phosphatases (PP1, PP2A, PP2B and PP5) in the brain was analyzed by Western blot. Lead exposure significantly impaired learning and resulted in a significant reduction in the expression of tau but increased the phosphorylation of tau at Ser199/202, Thr212/Ser214 and Thr231. PP2A expression decreased, whereas, PP1 and PP5 expression increased in lead-exposed rats. These results demonstrate that early postnatal exposure to lead decrease PP2A expression and induce tau hyperphosphorylation at several serine and threonine residues. Hyperphosphorylation of tau may be a mechanism of Pb-induced deficits in learning and memory.
Summary
We present the comprehensive chromatographic profiles of three scorpion species, Androctonus crassicauda, Androctonus bicolor, and Leiurus quinquestriatus, commonly inhabited to Middle East regions. Their venoms were milked by electrical stimulation, diluted with distilled water, properly mixed and centrifuged to separate the mucus from venom. The clear supernatant was filtered and the protein concentration was determined. Pre-diluted venoms were chromatographed on FPLC (fast protein liquid chromatography) and RP-HPLC (reversed-phase high-performance liquid chromatography) and the fractions were collected for molecular weight determination. Both techniques have resulted clearly distinguishable chromatographic patterns that can be used for identification of scorpion species and having a quick indication of venom toxicity.
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.
Abstract
A study on the concentration of natural and fallout radionuclides in environmental samples collected from different localities of Islamabad was performed. For the determination of gamma-emitters such as 238U, 232Th, 40K and 137Cs high purity germanium (HPGe) detector was used while for the analysis of 90Sr, a beta-emitter, liquid scintillation counting system was used. The indoor absorbed dose rate was measured by a CaF2 : Dy thermoluminescence detector. Other radiation parameters were also determined to evaluate the radiation hazard. All the results were well within the permissible limits showing that there is no radiation hazard in the environment of Islamabad.
