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Abstract
DNA Comet Assay method was carried out to detect irradiation treatment of some foods like meat, spices, beans and lentils. The fresh meat of cow and duck were irradiated up to radiation doses of 3 kGy, the spices (cardamoms and cumin black) were irradiated to radiation doses of 5, 10, 15 and 20 kGy while the beans (black beans and white beans) and lentils (red and green lentils) were irradiated to 0.5 and 1 kGy. All the foods were then analyzed for radiation treatment using simple microgel electrophoresis of single cells or nuclei (DNA Comet Assay). Sedimentation, lysis and staining times were adjusted to get optimized conditions for correct and easy analysis of each food. Using these optimized conditions, it was found out that radiation damaged DNA showed comets in case of irradiated food samples, whereas in non-treated food samples, round or conical spots of stained DNA were visible. Shape, length and intensity of these comets were also radiation dose dependent. Screening of unirradiated and irradiated samples by Comet Assay was successful in the case of all the foods under consideration under the optimized conditions of assay. Therefore, for different kinds of irradiated foods studied in the present study, the DNA Comet Assay can be used as a rapid, simple and inexpensive screening test.
Abstract
A rapid and sensitive spectrophotometric method has been developed for the determination of thorium using 0.04% Arsenazo-III in a 2M perchloric acid solution. Absorbance was measured in 1 cm cell and the complex has a sensitive absorption peak at 654 nm. The complex is formed instantly in perchloric acid and remains stable for 45 minutes with constant absorbance. Beer's law is obeyed in the range 1–60 g·g–1 of thorium concentration with a molar absorptivity at 654 nm = 3.07·105 M–1·cm–1 at 24±2°C. The foreign ions interference in thorium determination have been checked. The cations were tested at >60-fold excess of thorium, Mn(II), Fe(III), Co(II) and Ni(II) interfere negatively, whereas only Ce(III) has increased the absorbance. Among the anions, cyanide, phosphate, thiocyanate and acetate at 150-fold excess of thorium cause significant interference. However, thorium can bedetermined in the presence of nitrate, chloride, oxalate, tartrate, ascorbate, thiosulphate and citrate. The method has been applied on certified reference material for thorium determination after extractive separation and the result was found in good agreement with the certified value. The method has been also applied successfully to determine thorium at g·g–1 level in local ore samples with a precision of ±0.04%.
Abstract
Radiosynthesis of 99mTc-sitafloxacin (99mTc-STF) complex and its efficacy as a potential infection imaging agent was evaluated. Effect of sitafloxacin (STF) concentration, sodium pertechnetate (Na99mTcO4), stannous chloride dihydrate (SnCl2·2H2O), and pH on the % radiochemical purity yield (RCP) of 99mTc-STF complex was studied. A stable 99mTc-STF complex up to 120 min with maximum %RCP yield was observed by mixing 2 mg of STF with 3 mCi of Na99mTcO4 and 150 μL of SnCl2·2H2O (1 μg/μL in 0.01 N HCl) at a pH 5.5. Artificially infected rats with Staphylococcus aureus were used for studying the biodistribution behavior of the 99mTc-STF complex. After 30 min of the intravenous (I.V.) administration of the 99mTc-STF complex, 7.50 ± 0.10% was absorbed in the infected thigh of the rats and the uptake gradually increased to 18.50 ± 0.20% within 90 min. Rabbits with artificially induced infection were used for evaluating the scintigraphic accuracy. Higher uptake in the infected thigh was observed after 2 h of I.V. administration of the 99mTc-STF complex. Target to non-target organ ratio of the % absorbed dose incase of infected/normal muscle was 6.82 ± 0.40, 17.11 ± 0.60, and 23.13 ± 1.00% at 30, 60 and 90 min of administration. Stable and higher %RCP, higher uptake in the infected thigh, and spectral studies, recommend the 99mTc-STF for routine infection imaging.
This paper deals with a study of a class of functions called ‘bibasis analytic functions’. Using discrete powerz (n)?, discrete bibasic hypergeometric functions have been introduced.
A locally compact abelian topological groupG is constructed whose maximal torsion subgroup is finite but not a topological direct summand ofG.
Genomics provided biomedical scientists an inventory of all genes and sequences present in a living being. This provides an unique opportunity to the scientists to predict and study biological functions of these genes. The changes in the gene expression regulated by genomic sequences therefore reflect changes in the molecular processes working in a cell or tissue in response to external factors including exposure to toxic compounds and pathogens. Microarray offers a biotechnological revolution with the help of DNA chemistry, silicon chip technology and optics to be used to monitor gene expression for thousands of genes in one single experiment. Briefly, 20,000 to 100,000 unique DNA molecules get applied by a robot to the surface of silicon wafers (approximately the size of a microscope slide). Using a single microarray experiment, the expression level of 20,000 to 100,000 genes will be examined in one single experiment. Genomics and microarray have a significant role and impact on the design and development of modern detection and diagnostic tools in several different ways. Microarray tools are now used on regular basis for monitoring gene expression of large number of genes and also frequently applied to DNA sequence analysis, immunology, genotyping, and molecular diagnosing. For diagnostics, these tools can be used to distinguish and differentiate between different DNA fragments that differ by as little as a single nucleotide polymorphism (SNP). These microarrays can be divided based on the gene density spots that will be high density (≯10,000 spots) per slide, medium (<1000≯100) and low density (<100). High-density arrays have proven to be very useful in disease diagnosis especially in diagnosis and classification of different types of cancers. These microarray tools hold tremendous potential for pathogen detection, which will be comprised, of unique sets of genes (also referred to as “signatures”) able to unambiguously identify the species and strain of pathogens of interest.
Summary
Titan yellow has been adsorbed on a strongly basic anion-exchange resin. The effects of concentration, pH, time, and temperature on adsorption of the dye by the resin have been studied. The effects of surfactants on the distribution coefficients of metal ions were also studied. On the basis of distribution coefficients several binary separations of analytical importance (Zn(II) from Hg(II), Zn(II) from Pb(II), Cu(II) from Pb(II), Cd(II) from Pb(II), and Cu(II) from Hg(II) have been achieved on a column containing the Titan yellow-modified resin. Hg(II) and Pb(II) were selectively analysed in synthetic mixtures.
Abstract
Fission neutron spectrum averaged cross-sections were measured for the reactions64Zn(n, p)64Cu,67Zn(n, p)67Cu and68Zn(n, )65Ni by the activation technique, using radiochemical separations and -spectroscopy. The preparation of64Cu and67Cu in a nuclear reactor was studied. The64, 67Cu was separated from zinc matrix activity using anion exchange column technique.
Abstract
Effects of humidity and light conditions /fluoroscent light, sunlight and diffuse sunlight/ on the response of 2 mm thick clear polymethylmethacrylate /PMMA/ dosimeter during irradiation and during postirradiation storage were determined spectrophotometrically at 305 and 314 nm. The results showed that irradiation of dosimeters at 12–97% relative humidity did not result in any change in the response upto 2 weeks of post-irradiation storage. However, there is some decrease in the response at higher humidities />76%/ for longer storage time. Post-irradiation storage and dosimeters at constant relative humidity conditions between 35 and 97% had no effect on the response up-to 3 weeks. Post-irradiation storage at lower relative humidity /12%/ showed some decrease in the response for longer periods. The response of dosimeter is not very sensitive to short time exposure to diffuse sunlight and fluorescent light. However, a significant increase in the optical density was observed during exposure of dosimeters to direct sunlight.