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Sample records for 60co gamma irradiation

  1. Effect of 60Co-gamma whole-body irradiation on serum amylase level

    International Nuclear Information System (INIS)

    Changes of serum amylase activity in rats, after several doses of acut 60Co-gamma irradiation as a function of time were investigated. These changes proved to be of no diagnostic value in early radiation damage. (author)

  2. Immunohistochemical study on effects of [sup 60]Co [gamma] irradiation on salivary gland ducts of rat

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, Kazuhiko (Meikai Univ., Sakato, Saitama (Japan). School of Dentistry)

    1992-09-01

    Cytokeratin distribution in salivary glands was detected by use of polyclonal antikeratin antiserum (TK) and monoclonal antibodies (KL 1, RGE 53, and RPN 1164). The salivary glands of male rats received either 17.82 Gy or 27.97 Gy [sup 60]Co [gamma] irradiation in a single exposure and were then compared immunohistochemically with those of normal rats. Polyclonal anti-keratin antiserum (TK), which reacts with 41-65 KD keratins, stained almost all ducts in normal glands. RPN 1164 (no. 8 keratin) staining was negative in intercalated ducts of normal parotid and submandibular glands, but strongly positive in both striated and excretory ducts of these glands. Monoclonal antibody KL 1 (55-57 KD keratins) and RGE 53 (no. 18 keratin) did not bind to any ductal or acinar epithelia. Only in the sublingual gland were acini positive for TK staining, possibly indicating myoepithelial cells. No effects of [sup 60]Co [gamma] irradiation were apparent regarding keratin distribution in the intercalated in apical cytoplasm by [sup 60]Co [gamma] irradiation. Also, in the excretory duct, the basal side of the cells exhibited weakened staining following [sup 60]Co [gamma] irradiation were the most significant in the parotid and the least in the sublingual gland. Also this reaction depended upon the doses of [sup 60]Co used. The present findings suggested that negative or weakened staining at the basal and perinuclear portions of striated duct cells specifically reflects the primary or secondary cell damage produced by [sup 60]Co [gamma] irradiation. Since the distribution of cytoskeletal proteins in the cytoplasm reflects certain pathological conditions, immunohistochemical detection of these proteins seem to have a diagnostic value with respect to cellular injury. (J.P.N.) 77 refs.

  3. The influence of 60Co gamma irradiation for downy mildew infection on corn

    International Nuclear Information System (INIS)

    Corn seeds of Genjah kertas variety were irradiated with 60Co gamma in the range of 0 rad - 40.000 rads, at interval of 2000 rads, as preliminary investigation to obtain possibilities of corn mutation. Several agronomical effects of radiation on the seedling-plant such as seed germination, height of the seedling, ages of flowering, ages of harvesting, length and circle of the cob, 100U dry seeds weight, number and diameter of stomata, and percentage of downy mildew infection have been observed. The exact conclusion can be obtained only after testing the results of M2 and M3. (author)

  4. Cell survival of human tumor cells compared with normal fibroblasts following 60Co gamma irradiation

    International Nuclear Information System (INIS)

    Three tumor cell lines, two of which were shown to be HeLa cells, were irradiated with 60Co gamma irradiation, together with two cell cultures of normal human diploid fibroblasts. Cell survival was studied in three different experiments over a dose range of 2 to 14 gray. All the tumor cell lines showed a very wide shoulder in the dose response curves in contrast to the extremely narrow shoulder of the normal fibroblasts. In addition, the D/sub o/ values for the tumor cell lines were somewhat greater. These two characteristics of the dose response curves resulted in up to 2 orders of magnitude less sensitivity for cell inactivation of HeLa cells when compared with normal cells at high doses (10 gray). Because of these large differences, the extrapolation of results from the irradiation of HeLa cells concerning the mechanisms of normal cell killing should be interpreted with great caution

  5. Perna perna (LINNAEUS, 1758) mussels irradiated by {sup 60}CO gamma rays cytotoxicity evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Martini, Gisela A.; Pusceddu, Fabio H.; Rogero, Sizue O.; Rogero, Jose Roberto, E-mail: gisela.martini@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The aim of the present work was the study of ionizing radiation effects on aquatic biota regarding the location of nuclear facilities nearby coastal areas assuming the risk of leaks and nuclear accidents. Bivalve mollusks have been widely used in the monitoring of aquatic environment studies mainly for their sessile habit and pollutants bioconcentration ability. So marine mussel Perna perna (Bivalvia: Mytilidae) was used as organism test in this study. The study of radioactive toxicity was performed by cytotoxicity test exposing the organisms to 11Gy gamma radiation dose. After radiation the neutral red retention assay evaluated the lysosomal membrane integrity in the mussel hemocytes. 50% lethal dose assay (LD50) of gamma radiation on Perna perna mussels was carried out by exposure the organisms to {sup 60}Co gamma rays at doses ranging from 0 to 3000 Gy. The result of gamma radiation LD50 for these mussels was 1068 Gy and the neutral red retention time of irradiated organisms was about 47% lower than the control, non irradiated organisms. With the obtained results is expected to contribute in the study to identify the range of ionizing radiation doses which can cause toxic effects in marine invertebrates. (author)

  6. Evaluation of myotoxic activity of Bothropstoxin-1 irradiated with 60Co gamma rays

    International Nuclear Information System (INIS)

    Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules and has been proven to be a powerful tool to attenuate snake venoms toxicity without affecting their immunogenic properties. Snake venoms and their isolated toxins showed structural modifications after gamma radiation process, in aqueous solution, mainly by water radiolysis sub products. Free radical scavengers, such as NaNO3 and t-butanol, present selective effects on specific radical from water radiolysis. The NaNO3 has affinity by aqueous electron, while the t-butanol has affinity by hydroxyl radical. At the present work, we have investigated the myotoxic activity of Bothropstoxin-1 (BTHX-1), a K49 phospholipase, present in Bothrops jararacussu crude venom, before and after irradiation process, with or without scavenger substances presence. BTHX-1 was irradiated with 2 kGy of 60Co gamma rays, in aqueous solution and in the presence of oxygen. BALB/c mice were inoculated with either native or irradiated toxin, with or without scavenger substances. After 3 hours, blood samples were collected and the myotoxic activity was evaluated by LDH (lactate dehydrogenase) release. The muscular tissue damage was directly related to the LDH amounts released. Irradiated Bothropstoxin-1, with or without NaNO3 substance, caused less damage than their native counterpart. But irradiated toxin, in the presence of t-butanol, was so myotoxic as the native BTHX-1. These results indicate that irradiation of toxic proteins can promote significant modifications on their structures, but still retaining many of the original biological properties of their native counterparts. Additionally, some scavengers substances can change these gamma radiation effects. (author)

  7. Biochemical and pharmacological characterization of irradiated crotamine by gamma rays of 60Co

    International Nuclear Information System (INIS)

    The serum production in Brazil, the only effective treatment in cases of snakebites, uses horses that although large size, have reduced l lifespan compared with horses not immunized. Ionizing radiation has been shown as an excellent tool in reducing the toxicity of venoms and toxins isolated, and promote the achievement of better immunogens for serum production, and contributing to the welfare of serum-producing animals. It is known, however, that the effects of ionizing radiation on protein are characterized by various chemical modifications, such as fragmentation, cross-linking due to aggregation and oxidation products generated by water radiolysis. However, the action of gamma radiation on toxins is not yet fully understood structurally and pharmacologically, a fact that prevents the application of this methodology in the serum production process. So we proposed in this paper the characterization of crotamine, an important protein from the venom of Crotalus durissus terrificus species, irradiated with 60Co gamma rays. After isolating the toxin by chromatographic techniques and testing to prove the obtaining of pure crotamine, it was irradiated with gamma rays and subjected to structural analysis, Fluorescence and Circular Dichroism. Using high hydrostatic pressure tests were also conducted in order to verify that the conformational changes caused by radiation suffer modifications under high pressures. From the pharmacological point of view, muscle contraction tests were conducted with the objective of limiting the action of crotamine in smooth muscle as well as the change in the action of toxin caused structural changes to the front. Analysis of Circular Dichroism and Fluorescence showed changes in structural conformation of crotamine when subjected to gamma radiation and that such changes possibly occurring in the secondary and tertiary structure of the protein. The observed in pharmacological tests showed that the irradiated crotamine was less effective in

  8. Gamma 60Co-irradiation of organic matter in the Phosphoria Retort Shale

    Science.gov (United States)

    Lewan, M. D.; Ulmishek, G. F.; Harrison, W.; Schreiner, F.

    1991-04-01

    Irradiation experiments were conducted on a thermally immature rock sample of the Phosphoria Retort Shale and its isolated kerogen. A 60Co-source for gamma radiation was employed at dosages ranging from 81 to 885 Mrads, which are attainable by Paleozoic and Precambrian black shales with syngenetic uranium enrichments. Kerogen elemental, isotopic, and pyrolysate compositions are not affected at these dosages, but the bitumens extracted from the irradiated rock are affected. The major effects are reductions in the amounts of bitumen, acyclic isoprenoids, and high-molecular weight acyclic carboxylic acids. Natural differences in the amounts of bitumen and acyclic isoprenoid due to regional and stratigraphie variations in organic source input and depositional conditions make the radiation-induced reductions in these parameters difficult to use as indicators of natural radiation damage in black shales. However, the preferential reduction in the high-molecular weight acyclic carboxylic acids, which are ubiquitous in the living precursory organic matter, is diagnostic of experimental γ-irradiation but may not be diagnostic of natural irradiation. The overall process associated with radiation damage is polymerization by cross-linking through a free radical mechanism. As a result, irradiation of organic matter in black shales is more likely to retard rather than enhance petroleum generation.

  9. Irradiation effect on enzymatic activity of papain with {sup 60}Co-{gamma} rays

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio [Osaka Prefecture Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology

    1998-12-31

    An investigation was made on the durability of enzyme activity against {sup 60}Co-{gamma} irradiation at a dose up to 55 kGy/h using dry powder and aqueous solution of papain preparations on the market. Hybrid materials including bioactive molecules combined with biocompatible synthetic polymers are expected to have biocompatible properties and also biomimetic functions as a component of artificial organs for human body. The activity of papain in an aqueous solution was rapidly decreased at the early stage of irradiation through oxidation of SH group at its active site with active oxygen produced by the irradiation and then, partially recovered since SH group was reproduced in an anoxic state after O{sub 2} consumption in the solution irradiated at a high dose. A usual radiation method for sterilization was found applicable to decontamination of dry and frozen preparations of papain. When suitable conditions for radiation were chosen and N{sub 2} gas was purged to suppress the formation of free radicals, it was possible to keep the enzyme activity at more than 50% of the initial activity after radiation at 30 kGy. (M.N.)

  10. Study of irradiated bothropstoxin-1 with {sup 60}Co gamma rays: immune system behavior

    Energy Technology Data Exchange (ETDEWEB)

    Caproni, P.; Baptista, J.A.; Almeida, T.L. de; Nascimento, N. [Nuclear and Energy Research Institute (IPEN/CNEN-SP), SP (Brazil). Biotechnology Center; Passos, L.A.C. [State University of Campinas (UNICAMP), SP (Brazil). Lab. of Genetics and Embryo Cryopreservation

    2009-07-01

    Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules. Very promising results were obtained when crude animal venoms, as well as isolated toxins, were treated with 60Co gamma rays, yielding toxoids with good immunogenicity. The achievement of modified antigens with lower toxicity and preserved or improved immunogenicity can be very useful. Ionizing radiation has already been proven to be a powerful tool to attenuate snake venom toxicity without affecting, and even increasing, their immunogenic properties. However, little is known about the modifications that irradiated molecules undergo and even less about the immunological response that such antigens elicit. In the present work, we investigated the immunological behavior of bothropstoxin-1, a K49 phospholipase, before and after irradiation. Structural modifications of the toxin were analyzed by SDS-PAGE. Isogenic mice were immunized with either the native or the irradiated toxin. The circulating antibodies were isotyped and titrated by ELISA. According to our data, irradiation promoted structural modifications in the toxin characterized by higher molecular weight forms of proteins (aggregates and oligomers). The results also indicated that irradiated toxins were immunogenic and antibodies elicited by them were able to recognize the native toxin in ELISA. These findings suggest that irradiation of toxic proteins can promote significant modifications in their structures; however they still retain many of the original antigenic and immunological properties of native proteins. Also, our data indicate that irradiated proteins induce higher titers of IgG2a and IgG2b, suggesting that Th1 cells are predominantly involved in the immune response. (author)

  11. Effect of 60Co gamma-ray irradiation on dilute aqueous solutions of surfactants

    International Nuclear Information System (INIS)

    Present work deals with the effects of gamma irradiation from 60Co γ-ray source upon aqueous solutions of three kinds of surfactants. When dilute aqueous solutions of sodium dodecyl sulfate (SDS, anionic), cethyl trimethyl ammonium chloride (CTAC, cationic), and polyoxyethylene lauryl ether (POE, non-ionic) were irradiated with γ-rays at a room temperature, the residual concentration, products, surface tension, and forming power were examined by colorimetric method, IR spectrophotometric method, gaschromatography, Ross-Miles method, and Traube's stalagmometer etc. These surfactants were decomposed by the irradiation and thus the surface tension increased and the forming power, on the contrary, decreased with dose. Radiation chemical yields (G-value) of the degradation were about 1 for the solutions of SDS and CTAC, and about 0.3 for the POE solution. From the experimental results, it was found that following chemical reactions seem to occur followed by the radiolysis of water: a) bond cleavage of ester for SDS, of CN for CTAC, and of oxyethylene for POE, b) hydrogen abstraction from the surfactants, c) production of CO bond in the presence of dissolved oxygen. (auth.)

  12. Biochemical and pharmacological characterization of irradiated crotamine by gamma rays of {sup 60}Co; Caracterizacao bioquimica e farmacologica da crotamina irradiada por raios gama de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Karina Corleto

    2014-07-01

    The serum production in Brazil, the only effective treatment in cases of snakebites, uses horses that although large size, have reduced l lifespan compared with horses not immunized. Ionizing radiation has been shown as an excellent tool in reducing the toxicity of venoms and toxins isolated, and promote the achievement of better immunogens for serum production, and contributing to the welfare of serum-producing animals. It is known, however, that the effects of ionizing radiation on protein are characterized by various chemical modifications, such as fragmentation, cross-linking due to aggregation and oxidation products generated by water radiolysis. However, the action of gamma radiation on toxins is not yet fully understood structurally and pharmacologically, a fact that prevents the application of this methodology in the serum production process. So we proposed in this paper the characterization of crotamine, an important protein from the venom of Crotalus durissus terrificus species, irradiated with {sup 60}Co gamma rays. After isolating the toxin by chromatographic techniques and testing to prove the obtaining of pure crotamine, it was irradiated with gamma rays and subjected to structural analysis, Fluorescence and Circular Dichroism. Using high hydrostatic pressure tests were also conducted in order to verify that the conformational changes caused by radiation suffer modifications under high pressures. From the pharmacological point of view, muscle contraction tests were conducted with the objective of limiting the action of crotamine in smooth muscle as well as the change in the action of toxin caused structural changes to the front. Analysis of Circular Dichroism and Fluorescence showed changes in structural conformation of crotamine when subjected to gamma radiation and that such changes possibly occurring in the secondary and tertiary structure of the protein. The observed in pharmacological tests showed that the irradiated crotamine was less effective

  13. Grafting of synthetic polyelectrolyte onto polymer surfaces--comparison of glow discharge and 60Co-gamma-irradiation method

    International Nuclear Information System (INIS)

    Water soluble polyelectrolyte synthesized from natural rubber contains sulfamate and carboxylate groups similar to that of heparin. It is observed that synthetic heparinoid polyelectrolyte is capable of inhibiting blood coagulation. In the present study, we attempted to graft the same onto polystyrene and polymethylmethacrylate surfaces using glow discharge technique and 60Co-gamma-irradiation method, and the surfaces were compared with respect to water contact angle and platelet adhesion parameters. Heparinized surfaces are also evaluated for relative comparison

  14. Morphological and histological studies on freshwater prawn Macrobrachium rosenbergii (de man) irradiated with {sup 60}Co gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Stalin, A.; Broos, K.V. [P.G. and Research Department of Zoology, Jamal Mohamed College (Autonomous), Tiruchirappalli 620020, Tamil Nadu (India); Sadiq Bukhari, A., E-mail: abjmc@yahoo.in [P.G. and Research Department of Zoology, Jamal Mohamed College (Autonomous), Tiruchirappalli 620020, Tamil Nadu (India); Syed Mohamed, H.E. [P.G. and Research Department of Zoology, Jamal Mohamed College (Autonomous), Tiruchirappalli 620020, Tamil Nadu (India); Singhal, R.K. [Analytical Spectroscopy Section, Analytical Chemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 4000085 (India); Venu-Babu, P. [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Center, Trombay, Mumbai 4000085 (India)

    2013-11-15

    Graphical abstract: -- Highlights: •Analyzing the impact of {sup 60}Co gamma radiation (low doses) in M. rosenbergii. •LD{sub 50} identified in 30 Gy; Irradiated exhibits morphological changes than control. •Significantly decreased HSI and histological changes in irradiated groups. •Aberration severities increased as increased of dose level. •Biomonitoring tool in determining low dose radiation pollution in aquatic ecosystem. -- Abstract: This study was framed to investigate the {sup 60}Co gamma radiation induced morphological and histological variations in freshwater prawn Macrobrachium rosenbergii. The LD{sub 50} value of {sup 60}Co gamma irradiated M. rosenbergii observed (by probit analysis) at 30 Gy. Prawns were irradiated to four different dose levels (3 mGy, 30 mGy, 300 mGy and 3000 mGy) using Theratron Phoenix TeleCobalt Unit [P-33] and one control group (without irradiation) maintained separately. Irradiated groups exhibited several morphological variations such as discoloration; damaged rostrum; opaque coloration in cephalothorax; black bands and dot formation in abdomen; deformed uropods and telson in tail regions when compared with control group. The Hepato Somatic Index reflected the severity of radiation on hepatopancreas. Histological variations in gills, hepatopancreas and muscles of irradiated groups were observed. In gills, structural changes such as swollen and fused lamellae, abnormal gill tips, hyperplasic, necrotic and clavate-globate lamellae were observed in gamma irradiated prawns. Accumulation of hemocytes in hemocoelic space, interstitial sinuses filled with abnormal infiltrated hemocytes, the tubular epithelium with ruptured basal laminae, abnormal and coagulated lumen, necrotic tubules, thickened basal laminae, tissue debris, necrotic hepatocytes were observed in irradiated prawn hepatopancreas. In muscle, shrinkage of muscular fiber and necrotic musculature were observed in irradiated prawns. These structural alterations of

  15. Chemical changes in the chloroform-paraffin system irradiated by 60Co gamma-rays, 1

    International Nuclear Information System (INIS)

    It has been reported that the chloroform-paraffin-dye system have excellent sensitivity for radiation as a solid chemical dosimeter or a phantom. However, the chemical changes in the irradiated system are not examined in detail. In the present study, the effect of paraffin on changes in the above system of a liquid state irradiated by 60Co γ-rays was examined by using various normal paraffin, and the other variable factors on the changes were done. When the chloroform solution and the solution containing 25 per cent of paraffin by volume with 5.0 x 15-5 mol/liter of Methyl Yellow as a dye were irradiated by 2000 R, G values for the formation of hydrogen chloride in the both solutions were 8.4 and 10.8, respectively, and were little affected by the kind of those, from C6 (hexane) to C36 (hexatria-contane). These results suggest that chlorine radical formed by radiolysis of chloroform may react with hydrogen atom from paraffin, thereby increasing the amount of hydrogen chloride. Presence of oxygen increased G value of the chloroform solution from 7.6 to 8.4, but did little that of the solution containing paraffin. (author)

  16. Morphological and histological studies on freshwater prawn Macrobrachium rosenbergii (de man) irradiated with (60)Co gamma radiation.

    Science.gov (United States)

    Stalin, A; Broos, K V; Sadiq Bukhari, A; Syed Mohamed, H E; Singhal, R K; Venu-Babu, P

    2013-11-15

    This study was framed to investigate the (60)Co gamma radiation induced morphological and histological variations in freshwater prawn Macrobrachium rosenbergii. The LD50 value of (60)Co gamma irradiated M. rosenbergii observed (by probit analysis) at 30 Gy. Prawns were irradiated to four different dose levels (3 mGy, 30 mGy, 300 mGy and 3,000 mGy) using Theratron Phoenix TeleCobalt Unit [P-33] and one control group (without irradiation) maintained separately. Irradiated groups exhibited several morphological variations such as discoloration; damaged rostrum; opaque coloration in cephalothorax; black bands and dot formation in abdomen; deformed uropods and telson in tail regions when compared with control group. The Hepato Somatic Index reflected the severity of radiation on hepatopancreas. Histological variations in gills, hepatopancreas and muscles of irradiated groups were observed. In gills, structural changes such as swollen and fused lamellae, abnormal gill tips, hyperplasic, necrotic and clavate-globate lamellae were observed in gamma irradiated prawns. Accumulation of hemocytes in hemocoelic space, interstitial sinuses filled with abnormal infiltrated hemocytes, the tubular epithelium with ruptured basal laminae, abnormal and coagulated lumen, necrotic tubules, thickened basal laminae, tissue debris, necrotic hepatocytes were observed in irradiated prawn hepatopancreas. In muscle, shrinkage of muscular fiber and necrotic musculature were observed in irradiated prawns. These structural alterations of the organs it is felt could affect the vital physiological functions such as respiration, osmotic and ionic regulation in gills and muscles; absorption, storage and secretion of the hepatopancreas which in turn could adversely affect the growth and survival of freshwater prawn M. rosenbergii.

  17. Cutaneous mitochondrial protection by topical treatment of herbal antioxodiants following 60 Co-gamma irradiation

    International Nuclear Information System (INIS)

    To find out the effective dose of herbal antioxidants to elevate the cutaneous lipid peroxidation (LP) at optimal level, gamma irradiation of cutaneous microsomal fraction was performed at different doses and 200 Gy was chosen. The present findings indicate that the failure of succinate in suppression of mitochondrial LP of irradiated rats might be due to diminishing of mitochondrial antioxidants which had been reduced by free radicals (generated by irradiation), since succinate suppressed mitochondrial LKP in antioxidant-treated rats. From these points of view, topical application of either curcumin or ellagic acid could be beneficial in prevention of radiation skin cancer

  18. Effects of (60)Co gamma irradiation on behavior and gill histoarchitecture of giant fresh water prawn Macrobrachium rosenbergii (DE MAN).

    Science.gov (United States)

    Stalin, A; Broos, K V; Sadiq Bukhari, A; Syed Mohamed, H E; Singhal, R K; Venu-babu, P

    2013-06-01

    Present study was designed to observe the effects of (60)Co gamma radiation in behavioral and histological changes in the gills of giant fresh water prawn Macrobrachium rosenbergii. The adult prawns were irradiated with four different dose levels (3mGy, 30mGy, 300mGy and 3000mGy) and the control group (without irradiation) was maintained separately. Behavioral changes like hyperactivity, loss of balance, reduced swimming rate, slower rate of food intake and convulsions were observed in higher dose levels of 300mGy and 3000mGy. The histological alterations such as accumulated haemocytes in haemocoelic spaces, abnormal gill tips, lifted lamellar epithelium, swollen and fused lamellae, hyperplasic, necrotic, clavate-globate and complete disorganization of lamellae were observed in (60)Co gamma irradiated prawns. Significantly more considerable histological alterations were observed in the highest dose level of 3000mGy, but no mortality was evidenced. This study serves as biomonitoring tool to assess the radiation pollution in the aquatic environment.

  19. The Effect of 60Co Gamma Irradiation on Various Fractions of Human Blood-Plasma Proteins

    International Nuclear Information System (INIS)

    The potential usefulness of employing ionizing radiation to cold-sterilize biomedical products has stimulated interest in characterizing the radiation sensitivity of various biologicals like vitamins, antibiotics, enzymes, antibodies and blood plasma fractions. This report presents findings on the sensitivity of haemagglutinin activity in human sera exposed to cobalt-60 gamma radiation. At doses tested between 0.2 and 5.0 Mrad, α-isohaemagglutinins were found to be more readily inactivated than ß-isohaemagglutinins, but neither was completely inactivated in this range. Sterility, clotting and antihaemophilic activity were also assessed on irradiated and freeze-dried preparations of human plasma with no significant differences in response detected. (author)

  20. Characteristic evaluation of papain irradiated with {sup 60}Co {gamma}-rays for the purpose of sterilization

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio [Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology

    1998-09-01

    To establish irradiation sterilization method for hybrid biomedical materials containing bioactive molecules together with artificial polymers, we employed dry powder and aqueous solution of papain as a model and examined radiation tolerance with {sup 60}Co {gamma}-rays. The dry powder and frozen aqueous solution showed significant resistance after 30-kGy irradiation, indicating that commercial irradiation sterilization method for disposable medical supplies was applicable. Unfrozen aqueous solutions (10mg/ml), in contrast, showed significant drop of enzymatic activity within the early period of irradiation (ca. 0.5kGy) but 40% of the activity was recovered at ca. 3-kGy before total inactivation at 15kGy. Taking various conditions including dose rate, concentration of enzyme, oxygen and nitrogen bubbling into irradiation inactivation experiments, we demonstrated that inactivation of papain could be controlled under anoxic condition, such as nitrogen bubbling, increasing sample volume at high dose rates and high concentration of enzyme where dissolved oxygen was consumed rapidly. It is suggested that radiation inactivation of papain in the aqueous solution was occurred through reversible oxidation of the sulfhydryl group at the active site by free radicals derived from radiolysis of water and dissolved oxygen. (author)

  1. Some Results Of Gamma-60Co Irradiation Application To Breed New Soybean Varieties At Institute Of Agricultural Genetics, 2001 - 2007

    International Nuclear Information System (INIS)

    To overcome the disadvantage characters and continue create new genetical materials in new Soybean variety selection to get high yield, resistance to with disadvantage conditions, good quality. The Institute of Agricultural Genetics successfully combinated the good particularities of mutant varieties DT84/DT83 and received DT2001 variety, and from mutant DT90/DT84 received new variety DT96. These varieties quite resists with rare good drought-tolerant, high yield from 2000 to 3500 kg/ha, appropriate with all of 3 crops: spring, summer and winter and have wide adaptation. DT96, DT2001 varieties were adopted by MARD Scientific Council as New National Varieties. cooperated with Dalat Institute of Nuclear research treated the Gamma - 60Co Irradiation on Soybean and Vegetable Soybean. Irradiated dry seed of 3 varieties DT96, DT2001, DT158 with dose levels of 150, 200, 250 Gy in order to shorten the rise time and strengthen the drought resistance. At M3 generation had selected 3 lines D.96/26, D.01/58, D.58/08, D.58/224, which have rise time from 3 to 5 day shorter and yield higher than control (D.96/150, D.01/245). Irradiated the 2 vegetable Soybean DT02 (to ameliorate its thick shell, improve sweetness and resist with collapse) and DT06 (to ameliorate its heat resistance) with dose levels of 100, 140, 180, 220 Gy were received the generations and now continue being researching the M3 generation in 2007 summer crop. (author)

  2. Numerical simulation of 60Co-gamma irradiation effects on electrical characteristics of n-type FZ silicon X-ray detectors

    Science.gov (United States)

    Vigneshwara Raja, P.; Rao, C. V. S.; Narasimha Murty, N. V. L.

    2016-07-01

    This paper describes the gamma irradiation effects on the electrical characteristics of n-type float zone (FZ) silicon detectors by incorporating a 4-level 60Co-gamma radiation damage model in the commercial device simulator for plasma X-ray tomography diagnostics. In the simulations, a segmented n-type silicon detector (i.e. p+-n-n+ structure) is considered with varying substrate resistivity (ρ = 5.4, 2.5, and 0.3 kΩ cm). The simulation results have been validated with the reported experimental measurements carried out on similar device structures. The 60Co-gamma irradiation induced changes in the electrical characteristics of the detectors are analyzed up to the dose of 3500 Mrad. The possible gamma induced degradation in the X-ray response of the detectors is investigated from the changes in the effective doping concentration and the leakage current of the detectors. The survival of the gamma irradiated detectors is predicted from the simulation studies. The comparison between the 60Co-gamma and 14.1 MeV neutron irradiation effects (typical fusion environments) on silicon detectors is attempted.

  3. Study of the ionization of alkane-electron scavenger reactant mixtures irradiated by 60Co gamma rays

    International Nuclear Information System (INIS)

    This study deals with ionization of alkane-electron scavenger reactant mixtures, irradiated by 60Co γ-rays. It is shown that the extrapolated free-ion yields (extrapolated yield method) decrease with the reactant concentration. On the basis of ONSAGER model and theoretical treatment of MOZUMDER, the cross sections of epithermal electron attachment in hexane, cyclohexane, 2,2-dimethylbutane, cyclopentane, 2,2,4-trimethylpentane for CCl4, C7F14, C6H5Br, C6H5Cl, C6F14, (C6H5)2 are determined. A comparison between gas-phase and liquid-phase cross sections is established

  4. Cytotoxicity evaluation of Diethyltoluamide (DEET) in Perna perna (Linnaeus, 1758) mussels non-irradiated and irradiated with 60Co gamma radiation

    International Nuclear Information System (INIS)

    Recent studies have identified the presence of several emerging pollutants in aquatic environments. The occurrence in different environmental matrices has been continuously reported, highlighting the need for toxicity studies. The DEET (N,N-diethyl-meta-toluamide) is the active ingredient used in most insect repellents, and is present in many commercially available formulations. Apart from chemical pollutants, aquatic organisms are subject to exposure of ionizing radiation from natural sources or in the vicinity of nuclear power plants. The present study evaluated the toxicity of DEET in organisms irradiated and non-irradiated with 60Co gamma radiation, and the effects that radiation causes in lysosomes of hemocytes of Perna perna mussel. For this purpose, assays were performed to identify the acute toxicity of DEET concentration and the dose of gamma radiation able to cause mortality. Subsequently, cytotoxicity assays were carried out to assess the stability of the lysosomal membrane in organisms exposed to ionizing radiation and DEET. According to the results obtained in acute toxicity tests, the concentration of DEET that causes mortality of 50% exposed organisms (LC50) is 114,27 mg L-1, and the radiation dose that causes mortality (LD50) is 1068 Gy. In the cytotoxicity assays, the concentration of the non-observed effect (NOEC) for irradiated and non-irradiated organisms 0.0001 mg L-1 and observed effect concentration (LOEC) at concentrations above this. The IC25 (72h) for non-irradiated organisms was 0.0003 mg L-1 and IC50 (72h) was 0.0008 mg L-1 for irradiated and non-irradiated organisms. Despite of the concentrations of effect found in this study were higher than in the environment, both measurements are in the same order of magnitude and should be also take into account the possible synergistic effects of DEET with other contaminants in the aquatic environment. (author)

  5. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of {sup 60}Co; Estudo bioquimico e farmacologico das crotaminas nativa e irradiada com radiacao gama de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Mitake, Malvina Boni

    2000-07-01

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide from the South American rattlesnake venom, composed of 42 amino acid residues. It induces skeletal muscle spasms leading to a spastic paralysis of hind limbs in mice. The objective of this thesis was carry out biochemical and pharmacological studies of native and irradiated crotamine with {sup 60} Co. Crotamine was purified from Crotalus durissus terrificus venom by Sephadex G-100 gel filtration followed by ion exchange chromatography, using a Fast Performance Liquid Chromatography (FPLC) system. It was irradiated at 2 mg/ml in 0.15 M Na Cl with 2.0 kGy gamma radiation emitted by a {sup 60} Co source. The native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD{sub 50} and biodistribution. The native and irradiated crotamine were labelled with 29.6 MBq of {sup 125} I using chloramine T method, and separated in a Sephadex G-50 column. Male Swiss mice (35{+-} 5 g), were injected i.p. with o.1 mL (2.4 x 10{sup 6} cpm/mouse) of {sup 125} I native crotamine or with 0.4 mL (1.3 x 10{sup 6} cpm/mouse) of {sup 125} I irradiated crotamine. At 0.08; 0.25; 0.5; 1; 2; 4; 8; 12 and 24 hours the animal were killed by ether inhalation. Blood, spleen, liver, kidneys, brain, lungs, heart, and skeletal muscle were collected in order to determine radioactivity content. The results showed that gamma radiation did not change the protein concentration, the electroforetic profile or the primary structure of the protein, although differences were shown by spectroscopic techniques. The gamma radiation diminished the toxicity of crotamine, but it did not abolish bioactivity. Biodistribution studies showed that native and irradiated crotamine have hepatic metabolism and renal elimination. The native and irradiated crotamine have affinity by skeletal

  6. Structural and optical analysis of 60Co gamma-irradiated thin films of polycrystalline Ga10Se85Sn5

    Science.gov (United States)

    Ahmad, Shabir; Asokan, K.; Shahid Khan, Mohd.; Zulfequar, M.

    2015-12-01

    The present study focuses on the effects of gamma irradiation on structural and optical properties of polycrystalline Ga10Se85Sn5 thin films with a thickness of ∼300 nm deposited by the thermal evaporation technique on cleaned glass substrates. X-ray diffraction patterns of the investigated thin films show that crystallite growth occurs in the orthorhombic phase structure. The surface study carried out by using the scanning electron microscope (SEM) confirms that the grain size increases with gamma irradiation. The optical parameters were estimated from optical transmission spectra data measured from a UV-vis-spectrophotometer in the wavelength range of 200-1100 nm. The refractive index dispersion data of the investigated thin films follow the single oscillator model. The estimated values of static refractive index n0, oscillator strength Ed, zero frequency dielectric constant ε0, optical conductivity σoptical and the dissipation factor increases after irradiation, while the single oscillator energy Eo decreases after irradiation. It was found that the value of the optical band gap of the investigated thin films decreases and the corresponding absorption coefficient increases continuously with an increase in the dose of gamma irradiation. This post irradiation changes in the values of optical band gap and absorption coefficient were interpreted in terms of the bond distribution model.

  7. Toxoplasma gondii gamma irradiation using Co-60; Irradiacao do Toxoplasma gondii com gama do {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Serra-Freire, Nicolau Maues [Universidade Federal Rural do Rio de Janeiro, RJ (Brazil). Dept. de Parasitologia Animal; Maliska, Carmelindo [Hospital Central do Exercito, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear; Norberg, Antonio Neres [Instituto de Biologia do Exercito (IBEx), Rio de Janeiro, RJ (Brazil)

    1996-07-01

    The use of nuclear power through radiation for the destruction of microorganisms which cause food deterioration, infections and toxicosis, is specifically for peaceful purposes. Toxoplasma gondii is a protozoa responsible for illnesses in humans and animals. One of the most common ways of transmission is through raw or poorly cooked meat. There is little information on the resistance of T. gondii to radiation. The objective of this research is to determine the Minimum Lethal Dose (MLD) of gamma radiation for those microorganisms. Suspensions of T. gondii containing approximately one million taquizoites/ml were irradiated with doses between up 0,01 up to 0,15 kGy (Kilogray) and inoculated to mice. The surviving T. gondii were re-irradiated with 0,01 up to 0,16 kGy. The irradiated protozoa were totally destroyed with a 0,15 kGy dose (MLD). Taquizoites issued from live protozoa of 0,14 kGy also were completely destroyed with dose of 0,15 kGy. No increase in resistance was observed regarding the non irradiated protozoa. (author)

  8. Development of irradiator {sup 60}Co sources

    Energy Technology Data Exchange (ETDEWEB)

    Mosca, Rodrigo C.; Moura, Eduardo S.; Zeituni, Carlos A.; Mathor, Monica B., E-mail: rcmosca@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    According to a recent report by the International Agency for Research on Cancer (IARC) / WHO (2008-2010), the global impact of cancer more than doubled in 30 years. In this report, it was estimated that occurred about 12 million new cancer cases and 7 million deaths. In Brazil in 2010, with estimates for the year 2011, point to the occurrence of 489,270 new cases of cancer. Among the possibilities for cancer treatment, radiotherapy is one of the most important therapeutic and resources used to combat it. However, inherent complications of treatment can occur such as tiredness, loss of appetite, radiodermatitis and in more extreme cases late radionecrosis. In order to reproduce a point of radionecrosis in the vicinity of radiodermatitis to mimic these effects in animals, producing a model for assessment of tissue repair, we propose the setting up of an irradiator source of collimated {sup 60}Co. The development of was based on 11 sources of {sup 60}Co with 1 mm thickness that were inserted by inference in stainless steel 'gate-source' screw (patent pending) and later adjusted in a cross-shaped arrangement reinforced so that the beam radiation is directed to a target point, saving for other regions around this target point. The main use of this irradiator with sources of {sup 60}Co is just one cause radionecrosis point (target point) of approximately 5 mm{sup 2} with a surrounding and adjacent area of radiodermatitis around about 8 to 10 mm{sup 2} in laboratory animals for subsequent coating with epidermal-dermal matrix populated by a cell culture of human fibroblasts, keratinocytes and mesenchymal stem cells. With that said, its use will be valuable for evaluation of curative treatments against the bone and radionecrosis or palliative treatment rather than as it is currently assumed. (author)

  9. Optimization of process parameters for the inactivation of Lactobacillus sporogenes in tomato paste with ultrasound and {sup 60}Co-{gamma} irradiation using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Ye Shengying [College of Food Science, South China Agricultural University, Wushan, Guangzhou, GD 510640 (China)], E-mail: yesy@scau.edu.cn; Qiu Yuanxin; Song Xianliang; Luo Shucan [College of Food Science, South China Agricultural University, Wushan, Guangzhou, GD 510640 (China)

    2009-03-15

    The processing parameters for ultrasound and {sup 60}Co-{gamma} irradiation were optimized for their ability to inactivate Lactobacillus sporogenes in tomato paste using a systematic experimental design based on response surface methodology. Ultrasonic power, ultrasonic processing time and irradiation dose were explored and a central composite rotation design was adopted as the experimental plan, and a least-squares regression model was obtained. The significant influential factors for the inactivation rate of L. sporogenes were obtained from the quadratic model and the t-test analyses for each process parameter. Confirmation of the experimental results indicated that the proposed model was reasonably accurate and could be used to describe the efficacy of the treatments for inactivating L. sporogenes within the limits of the factors studied. The optimized processing parameters were found to be an ultrasonic power of 120 W with a processing time of 25 min and an irradiation dose of 6.5 kGy. These were measured under the constraints of parameter limitation, based on the Monte Carlo searching method and the quadratic model of the response surface methodology, including the a/b value of the Hunter color scale of tomato paste. Nevertheless, the ultrasound treatment prior to irradiation for the inactivation of L. sporogenes in tomato paste was unsuitable for reducing the irradiation dose.

  10. Chemical changes in the chloroform-paraffin-dye system irradiated with 60Co gamma-rays, 2

    International Nuclear Information System (INIS)

    Studies have been carried out on the amount of hydrogen chloride formed by the radiolysis of chloroform in a solid paraffin-chloroform-Methyl Yellow system, and the color changes from yellow to red and absorption energy observed. The amount of hydrogen chloride formed and the intensity of the red color were determined with a pH meter, a spectrophotometer, and a color/ color-difference meter. It was found that the color-difference meter had the most excellent spectral response and sensitivity for measurement of the irradiated sample, and that the color-difference, ΔE, obtained by reflectometry increased proportionally with the increase in the radiation dose throughout a region of 100 -- 5000 R. When a solid sample composed of 1.0 kg paraffin (m.p. 62 -- 640C), 0.74 kg chloroform and 3.4 x 10-3 mol Methyl Yellow was subjected to 1000 R irradiation at 200C, 2.5 x 1014 molecules of hydrogen chloride were formed in 1.0 g of the solid sample with the absorption energy of 5.9 x 1016 eV, 3.2 x 1016 eV of which contributed to chloroform as the absorption energy. (author)

  11. Effects of gamma irradiation of the 60 Co on antimicrobial action of plant extracts of bark and leaves of Schinus terebinthifolius Raddi

    International Nuclear Information System (INIS)

    This study aimed to evaluate the potential for antimicrobial activity in vitro of extracts of bark and leaves of S. terebinthifolius treated with 60Co gamma radiation. 5,0 doses were used; 7.5 and 10 kGy, being held non-irradiated controls. To determine the antimicrobial activity was applied to the disc diffusion technique to evaluate the diameter of the inhibition zones against Gram-positive bacteria, gram-negative bacteria, alcohol-acid-resistant and yeast. Antimicrobial activity was considered significant for halos ≥ 15 mm. The results indicate an intensification of antimicrobial action of bark extracts, the 5.0 kGy, against S. aureus. Was held the micro dilution in broth to determine the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of peels extracts, compared to eight clinical isolates of S. aureus. The MBC values showed that ionizing radiation did not produce the increased of anti bacteriostatic action of S. terebinthifolius, but the results indicated that S. terebinthifolius bark extracts can be used as an antimicrobial agent and ionizing radiation as an important alternative in this conservation feature

  12. Seed germination of peanuts irradiated with cobalt (60CO)

    International Nuclear Information System (INIS)

    This work was realized to evaluate the effect of gamma irradiation (60Co) at doses 0, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00 and 4.00 kGy, on germination of seeds of peanut, cultivar BR1. Irradiation Department of Nuclear, UFPE, where he received after the irradiation, they were stored in packing of PET and polyethylene braided with a time of 90 days. Through the results, obtained monthly, concluded that the dose of 0.5 kGy was effective in the germination of seeds of peanut, not affecting its power of germination and overcoming the witness within 30 to 60 days. (author)

  13. Thermal stability of formulations of PVC irradiated with {gamma} of {sup 60}; Estabilidad termica de formulaciones de PVC irradiadas con {gamma} de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Martinez P, M.E.; Carrasco A, H. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: memp@nuclear.inin.mx; Castaneda F, A.; Benavides C, R.; Garcia R, S.P. [CIQA, 25100 Saltillo, Coahuila (Mexico)

    2004-07-01

    The industry of cables and wires frequently use cable isolations with base of formulations of PVC, in those that stabilizer has usually been used with the help of heavy metals, as the lead, which is toxic. To solve the problem, from the 2002 one has come studying in combined form in the National Institute of Nuclear Research ININ and the Center of Investigation in Applied Chemistry CIQA, the modifications induced by the radiation in formulations with the help of vinyl poly chloride PVC. In these formulations, prepared with cross linking agent, plastifying industrial grade, stuff and non toxic stabilizers of calcium estearate and zinc industrial grade, it is sought to replace the stabilizer of Pb. For this were irradiated it test tubes of PVC with gamma radiation of cobalt 60 to three different dose in atmospheres of air and argon. Later it was determined their thermal stability at different times of heating and it was measured the Young modulus by means of thermo mechanical analysis. Those results obtained together with other techniques of characterization suggest that the irradiated proposed formulation can substitute the one stabilized with lead. (Author)

  14. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818) DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818)

    OpenAIRE

    Elaine Barros da Costa CARVALHO; Melo, Ana Maria Mendonça de Albuquerque; Mauricy Alves da MOTTA

    1999-01-01

    The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony...

  15. Cytotoxicity evaluation of Diethyltoluamide (DEET) in Perna perna (Linnaeus, 1758) mussels non-irradiated and irradiated with {sup 60}Co gamma radiation; Avaliacao da citotoxicidade do dietiltoluamida (DEET) em mexilhoes Perna perna (Linnaeus, 1758) irradiados e nao irradiados com radiacao gama de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Martini, Gisela de Assis

    2013-07-01

    Recent studies have identified the presence of several emerging pollutants in aquatic environments. The occurrence in different environmental matrices has been continuously reported, highlighting the need for toxicity studies. The DEET (N,N-diethyl-meta-toluamide) is the active ingredient used in most insect repellents, and is present in many commercially available formulations. Apart from chemical pollutants, aquatic organisms are subject to exposure of ionizing radiation from natural sources or in the vicinity of nuclear power plants. The present study evaluated the toxicity of DEET in organisms irradiated and non-irradiated with {sup 60}Co gamma radiation, and the effects that radiation causes in lysosomes of hemocytes of Perna perna mussel. For this purpose, assays were performed to identify the acute toxicity of DEET concentration and the dose of gamma radiation able to cause mortality. Subsequently, cytotoxicity assays were carried out to assess the stability of the lysosomal membrane in organisms exposed to ionizing radiation and DEET. According to the results obtained in acute toxicity tests, the concentration of DEET that causes mortality of 50% exposed organisms (LC50) is 114,27 mg L{sup -1}, and the radiation dose that causes mortality (LD50) is 1068 Gy. In the cytotoxicity assays, the concentration of the non-observed effect (NOEC) for irradiated and non-irradiated organisms 0.0001 mg L-1 and observed effect concentration (LOEC) at concentrations above this. The IC25 (72h) for non-irradiated organisms was 0.0003 mg L-1 and IC50 (72h) was 0.0008 mg L{sup -1} for irradiated and non-irradiated organisms. Despite of the concentrations of effect found in this study were higher than in the environment, both measurements are in the same order of magnitude and should be also take into account the possible synergistic effects of DEET with other contaminants in the aquatic environment. (author)

  16. Decontamination of fermented chicken feet by 60Co irradiation

    International Nuclear Information System (INIS)

    Fermented chicken feet was treated by 60Co irradiation, and the aerobic plate count, enumeration of coliforms, pathogens and TBARS value were measured during storage. The results showed that, aerobic plate count of all irradiated samples was lower than control, and enumeration of coliforms, and pathogens of Staphylococcus aureus, Shigella, Salmonella were not detected. TBARS value of all treatments was stable during 60 d storage. It could be concluded that 60Co irradiation of chicken feet was an effective method to prolong its shelf life. (authors)

  17. Effect of dose-rate of gamma irradiation (60Co) on the anti nutritional compounds phytic acid and antitrypsin on soybean (glycine max L.)

    International Nuclear Information System (INIS)

    An investigation on the effect of gamma irradiation at different dose-rate on the anti-nutritional compounds (phytic acid and antitrypsin) and the color of soybean has been conducted. The purpose of the study was to analyze the influence of the dose-rate on the rate of change of anti-nutritional compounds and color. Samples were irradiated with dose-rates of 1.30; 3.17; 5.71 and 8.82 kGy/hour with irradiation time varied from 0.5 to 55 hours. Phytic acid content and antitrypsin activity, as well as their L α b color values were analyzed. Results showed that a simple first order kinetics model can be used to describe changes in the concentration of the anti-nutritional compounds and color soybeans during the radiation processing. Data indicate that irradiation process at higher dose-rate (shorter time) is more effective in destroying anti-nutritional compounds as compared to that of irradiation process at lower dose-rate (longer time). Furthermore, irradiation process at higher dose-rate (shorter time) also have less detrimental effect on color of the soybean and the resulted soybean flour as compared to that of irradiation process at lower dose-rate (longer time). These findings suggest that irradiation process at a same dose may potentially be optimized by selecting the most appropriate combination of dose-rate and time of irradiation. (author)

  18. Study of {sup 60}Co as gamma source in backscatter gamma densitometers

    Energy Technology Data Exchange (ETDEWEB)

    Gholipour Peyvandi, R.; Taheri, A.; Rahmanzadeh Tootkaleh, S.; Askari Lehdarboni, M. [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Islami Rad, S.Z. [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of); Univ. of Qom (Iran, Islamic Republic of). Dept. of Physic

    2015-07-15

    In this work the performance of backscatter gamma densitometer is studied using {sup 60}Co as gamma source. The ability of the densitometer to determine the liquid's interfaces in multi-phase flows was assessed. The aim mainly was to investigate the possibility of using {sup 60}Co in this system. Furthermore, a comparison between {sup 60}Co and was done. The obtained results indicate that {sup 60}Co can be advantageous in this regard.

  19. Study of the effect of gamma irradiation (60 Co) on the quality of sugar cane spirit and on the cask of maturation

    International Nuclear Information System (INIS)

    The ageing or maturing process of drink improves the sensorial characteristics of the product making it a qualified drink with higher economical value. The traditional maturing method of drinks involves their interaction with wood and irradiation can accelerate this ageing process. Sugar cane spirit and oak barrels with a 20 L capacity were treated using gamma irradiation (150 Gy). Physical-chemical and chromatographic analyses were constantly performed for 390 days during the drink ageing period. The sugar cane spirit and barrel irradiation did not change most volatile components of the same type coefficient such as volatile acidity, esters, superior alcohols and furfural throughout the 390 days. There is evidence, however, that some component parameters like aldehydes, tannin, color and copper concentration are in some way influenced resulting in partial acceleration of the ageing or maturing process. At the end of the ageing period, a sensorial analysis was made using 30 non-trained people who tasted the drink. The ageing process acceleration was confirmed by the sensorial evaluation, where the irradiated sugar cane spirit and/or barrel had higher approval regarding all parameters analyzed (scent, flavor and appearance). (author)

  20. Study of the effect of gamma irradiation (60CO) on the quality of sugar cane spirit and on the cask of maturation

    International Nuclear Information System (INIS)

    The ageing or maturing process of drink improves the sensorial characteristics of the product making it a qualified drink with higher economical value. The traditional maturing method of drinks involves their interaction with wood and irradiation can accelerate this ageing process. Sugar cane spirit and oak barrels with a 20 L capacity were treated using gamma irradiation (150 Gy). Physical-chemical and chromatographic analyses were constantly performed for 390 days during the drink ageing period. The sugar cane spirit and barrel irradiation did not change most volatile components of the same type coefficient such as volatile acidity, esters, superior alcohols and furfural throughout the 390 days. There is evidence, however, that some component parameters like aldehydes, tannin, color and copper concentration are in some way influenced resulting in partial acceleration of the ageing or maturing process. At the end of the ageing period, a sensorial analysis was made using 30 non-trained people who tasted the drink. The ageing process acceleration was confirmed by the sensorial evaluation, where the irradiated sugar cane spirit and/or barrel had higher approval regarding all parameters analyzed (scent, flavor and appearance)

  1. Different gamma ray (60 Co) dose effects on Sorghum genotype germination

    International Nuclear Information System (INIS)

    In agriculture, applying irradiation is a very valuable way of obtaining vegetable products for human and animal consumption. Cobalt-60, one of the main sources of gamma-rays, is considered an important tool in plant breeding programs, which have the objective of promoting genetic variability of cultivars with resistance to adverse environments. In this research, the effects of different 60Co doses on germination vigor and seed germination velocity of forage sorghum genotypes were evaluated. The study was carried out at the IPA (Empresa Pernambucana de Pesquisa Agropecuaria) in Recife, Pernambuco, Brazil. The work was installed in germination boxes, following laboratory recommendations. Thus, a experiment involving three sorghum genotypes (IPA 467-4-2, IPA 02-03-01, and Sudan 4202), five 60Co doses (Zero, 150, 300, 350, and 400 Gy), was set up. The sees were irradiated before the beginning of the experiment being exposed to gamma rays from a 60Co-source (cobalt irradiator) at DEN (Nuclear Engineering Department) of the UFPE (Pernambuco Federal University), Brazil. The work also had the objective of evaluating the sorghum genotypes x 60Co dose interaction. The main results obtained showed that the sorghum genotype IPA 02-03-01 presented the greatest values of germination and vigor percentages, and seed germination velocity, when compared to the others evaluated, on 350 and 400 Gy of 60Co doses. (author)

  2. Effect of Irradiation of 60CO Gamma Rays on Growth of Garlic (Allium Sativum L) Plants Cv. Lumbu Hijau at Low Land Area

    International Nuclear Information System (INIS)

    Garlic originally come from the sub tropical area. In Indonesia, garlic is grown generally in high land area with an altitude between 1000 - 1600 m above sea level. Therefore, the area for growing and producing garlic is limited. Besides, genetic variation of garlic is very narrow since garlic belongs to vegetatively propagated crops. An effort for increasing genetic variation of garlic was done by exposing garlic cloves to gamma rays in order to obtain garlic mutant lines adapted to low land area. Garlic cloves were exposed to different doses of gamma rays 0 (untreated) 2, 4, 6, 8 and 10 Gy at the Centre for Research and Development of Isotope and Radiation Technology. Each dose consisted of 150 garlic cloves. Untreated and irradiated garlic cloves were grown at Bandar Buat Experimental Station (50 m above sea level), Padang, West Sumatera. The experiment was arranged in a randomized block design with three replication. The parameter observed were percentage of grown plants and survival harvested plants, plant height, leaf number, chlorophyll content, number of stomata, plant age, number of cloves per bulbs, fresh, dry weight and diameter of bulbs. The result indicated that the dose of gamma rays 6 Gy is an advantage dose for obtaining well adapted garlic mutant lines in the low land area. (author)

  3. Radiolytic degradation scheme for 60Co-irradiated corticosteroids

    Energy Technology Data Exchange (ETDEWEB)

    Kane, M.P.; Tsuji, K.

    1983-01-01

    The cobalt 60 radiolytic degradation products have been identified in the following corticosteroids: cortisone, cortisone acetate, hydrocortisone, hydrocortisone acetate, hydrocortisone sodium succinate, isoflupredone acetate, methylprednisolone, methylprednisolone acetate, prednisolone, prednisolone acetate, and prednisone. Two major types of degradation processes have been identified: loss of the corticoid side chain on the D-ring to produce the C-17 ketone and conversion of the C-11 alcohol, if present, to the C-11 ketone. Minor degradation products derived from other changes affecting the side chain are also identified in several corticosteroids. These compounds are frequently associated in corticosteroids as process impurities or degradation compounds. No new radiolytic compounds unique to 60Co-irradiation have been found. The majority of corticosteroids have been shown to be stable to 60Co-irradiation. The rates of radiolytic degradation ranged from 0.2 to 1.4%/Mrad.

  4. Planning a 60Co Irradiation Facility for Fruit Preservation

    International Nuclear Information System (INIS)

    A conceptual design for a conveyor system is proposed for use in fruit irradiation. The seasonal nature of the fruit harvest requires that the 60Co source inventory should be sufficient to meet the demand at peak season, but this would be excessive at the beginning and towards the end of the harvest. Because of the short crop period the possibility of other irradiation services should be exploited to ensure full utilization of the facility. For successful extension of fruit shelf-life rigid practices in pre-irradiation treatment are essential and careful packaging is indispensable to the operation of the irradiator. Based on the time required for construction and equipment supply, a period of 18 months should be assumed for completion of the project. (author)

  5. Planning a 60Co irradiation facility for fruit preservation

    International Nuclear Information System (INIS)

    A conceptual design for a conveyor system is proposed for use in fruit irradiation. The seasonal nature of the fruit harvest requires that the 60Co source inventory should be sufficient to meet the demand at peak season, but this would be excessive at the beginning and towards the end of the harvest. Because of the short crop period the possibility of other irradiation services should be exploited to ensure full utilization of the facility. For successful extension of fruit shelf-life rigid practices in pre-irradiation treatment are essential and careful packaging is indispensable to the operation of the irradiator. Based on the time required for construction and equipment supply, a period of 18 months should be assumed for completion of the project. (author)

  6. Activity evaluation from different native or irradiated with {sup 60} Co gamma rays snake venoms and their inhibitory effect on Leishmania (Leishmania) amazonensis; Avaliacao da atividade de diferentes venenos de serpentes, nativos ou irradiados, com radiacao gama de {sup 60} Co, quanto ao poder inibitorio do crescimento de Leishmania (Leishmania) amazonensis

    Energy Technology Data Exchange (ETDEWEB)

    Lourenco, Cecilia de Oliveira

    2000-07-01

    Cutaneous leishmaniasis is a disease, caused by Leishmania parasites, that occurs frequently in tropical and sub-tropical regions of the world. Skin lesions that could results in disfiguring aspect characterize it. The treatment is based on few drugs as antimony salts or pentamidine that are toxic with increasing resistance by the parasite. Alternative forms of disease treatment are in constant search, including natural components as snake venoms. Previous studies demonstrate that some components of snake venoms have an inhibitory effect against those parasites, including Leishmania species. Although snake venoms presented high toxicity, several methods have been described to detoxify most or some of their toxic components, with favorable results by the use of gamma irradiation. In this report we tested several native and irradiated snake venoms for inhibitory effect against Leishmania (Leishmania) amazonensis parasite and LLCMK{sub 2} mammalian cells, with enzymatic tests and electrophoresis. There are significant activity in Acanthophis antarcticus, Agkistrodon bilineatus, Bothrops moojeni, Bothrops jararaca, Hoplocephalus stephensi, Naja melanoleuca, Naja mossambica, Pseudechis australis, Pseudechis colletti, Pseudechis guttatus and Pseudechis porphyriacus, venom being inactive Pseudonaja textilis, Notechis ater niger, Notechis scutatus. Oxyuranus microlepidotus and Oxyuranus scutellatus venoms. After 2 KGy of {sup 60}Co irradiation most venom loses significantly their activity. Venoms with antileishmanial activity presented L-amino acid oxidase (L-AO) activity and showed common protein with a molecular weight about 60kDa in SDS-PAGE. These results indicate that L-AO activity in those venoms are probably related with antileishmanial effect. (author)

  7. Dosimetric response of united, commercially available CTA foils for 60Co gamma rays

    International Nuclear Information System (INIS)

    The usefulness of two kinds of untinted CTA foils: Fuji CTR-125 dosimetric foil and technical CTA-T foil, produced by 'Zaklady Chemiczne, 'Gorzow Wielkopolski' as support for light-sensitive layers of amateur photo-films, for 60Co gamma ray dosimetry was investigated. In spite of rather bad physical parameters of the technical foil (spread of foil thickness, high and different initial absorbance) the dosimetric response of both foils for 60Co gamma rays was similar. The CTA-T foil can be used for routine dosimetry providing that dosimetric signals have to be calculated exactly as recommended by the ASTM (American Society for Testing and Materials) standard, i.e. as the difference of absorbance of irradiated and (the same) non-irradiated foil. Any other approach may lead to high errors of dose evaluation. The last is true also for other CTA foils, especially after long self-life. (author)

  8. Experiments for inactivation of mycoplasms and bacteria in calf sera, using 60Co irradiation

    International Nuclear Information System (INIS)

    The use of 60Co gamma radiation to inactivate mycoplasms in calf serum, newborn calf serum, and fetal calf serum is reported. A dose of 3 kGy, independent of dose rate, was found to be sufficient for inactivation in the above sera of several mycoplasms, including Acholeplasma laidlawii, Mycoplasma orale, M. arginini, M. hyorhinis, and M. bovis. The critical dose proved to be at 2 kGy. No difference was found to exist between the above species in susceptibility to irradiation in diluted sera (50% and 10% in Eagle MEM). Sensibility of wild mycoplasm strains was found to be identical with that of laboratory strains. Hence, 60Co gamma irradiation of sera appears to be a safe method by which to make sera free of mycoplasms. Bacillus subtilis in calf serum was inactivated by doses above 18 kGy, with the critical dose being 15 kGy. (author)

  9. A comparison of ionizing radiation damage in CMOS devices from 60Co gamma rays, electrons and protons

    Institute of Scientific and Technical Information of China (English)

    HE Sao-Ping; YAO Zhi-Bin; ZHANG Feng-Qi

    2009-01-01

    Radiation hardened CC4007RH and non-radiation hardened CC4011 devices were irradiated using 80Co gamma rays, 1 MeV electrons and 1--9 MeV protons to compare the ionizing radiation damage of the gamma rays with the charged particles. For all devices examined, with experimental uncertainty, the radiation induced threshold voltage shifts (△Vth) generated by 60Co gamma rays are equal to that of 1 MeV electron and 1-7 MeV proton radiation under 0 gate bias condition. Under 5 V gate bias condition, the distinction of threshold voltage shifts (△Vth) generated by 60Co gamma rays and 1 MeV electrons irradiation are not large, and the radiation damage for protons below 9 MeV is always less than that of 60Co gamma rays. The lower energy the proton has, the less serious the radiation damage becomes.

  10. Effects of gamma irradiation of the {sup 60} Co on antimicrobial action of plant extracts of bark and leaves of Schinus terebinthifolius Raddi; Efeitos da radiacao gama do {sup 60} Co sobre a acao antimicrobiana de extratos vegetais de cascas e folhas de Schinus terebinthifolius Raddi

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edvane Borges da; Santos, Gustavo Henrique Farias dos; Amaral, Ademir de Jesus [Universidade Federal da Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Lima, Jeniffer Maiza de Souza [Universidade Federal da Pernambuco (CAV/UFPE), Vitoria de Santo Antao, PE (Brazil); Xisto, Kesia; Araujo, Rosilma de Oliveira [Universidade Federal da Pernambuco (DA/UFPE), Recife, PE (Brazil). Dept. de Antibioticos

    2014-07-01

    This study aimed to evaluate the potential for antimicrobial activity in vitro of extracts of bark and leaves of S. terebinthifolius treated with {sup 60}Co gamma radiation. 5,0 doses were used; 7.5 and 10 kGy, being held non-irradiated controls. To determine the antimicrobial activity was applied to the disc diffusion technique to evaluate the diameter of the inhibition zones against Gram-positive bacteria, gram-negative bacteria, alcohol-acid-resistant and yeast. Antimicrobial activity was considered significant for halos ≥ 15 mm. The results indicate an intensification of antimicrobial action of bark extracts, the 5.0 kGy, against S. aureus. Was held the micro dilution in broth to determine the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of peels extracts, compared to eight clinical isolates of S. aureus. The MBC values showed that ionizing radiation did not produce the increased of anti bacteriostatic action of S. terebinthifolius, but the results indicated that S. terebinthifolius bark extracts can be used as an antimicrobial agent and ionizing radiation as an important alternative in this conservation feature.

  11. Response of adrenal gland to whole body 60Co irradiation

    International Nuclear Information System (INIS)

    Whole body of the adult albino rates was exposed to 60Co radiation in a single dose of 600 R. Following irradiation the adrenal serotonin level was found higher till the end of 8th week except a fall on 14th day, whereas the blood 5HT level remained lower than the normal except a slight rise at the end of 1st week and dropped down at 14 days followed by a further rise. The blood catecholamine level was found increased at the end of 14th day followed by a fall at 4th and 8th weeks, but the levels were moving round the normal value. The histological studies of adrenal gland showed degranulation and hypertrophy of adrenal cortex and medullary cells at various intervals of post-irradiation. On the whole it is observed that maximum changes in the level of biogenic amines take place within 14 days after irradiation, and maximum rate of mortality also coincide with this period. Thus bringing out the fact that adrenal bioamines play an important role in the vital activities of the animals. (author)

  12. Gamma {sup 60} Co D L {sub 50/30} of Biomphalaria glabrata (Say, 1818)

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Elaine Barros da Costa; Melo, Ana Maria Mendonca de Albuquerque; Motta, Mauricy Alves da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    1999-12-01

    The variation of resistance to {sup 60} Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell {sup 60} Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL{sub 50/30}=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

  13. Gamma 60 Co D L 50/30 of Biomphalaria glabrata (Say, 1818)

    International Nuclear Information System (INIS)

    The variation of resistance to 60 Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60 Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

  14. Distribution of 60Co and 54Mn in graphite material of irradiated HTGR fuel assemblies

    International Nuclear Information System (INIS)

    Distribution of 60Co and 54Mn was measured in the graphite sleeves and blocks of the third and fourth HTGR fuel assemblies irradiated in the Oarai Gas Loop-1 (OGL-1), which is a high temperature inpile gas loop installed in the Japan Materials Testing Reactor (JMTR) of Japan Atomic Energy Research Institute (JAERI). Axial and circumferential profiles were obtained by gamma spectrometry, and radial profiles by lathe sectioning with gamma spectrometry. Distribution of 60Co is in good agreement with that of thermal neutron flux, and the Co content in the graphite is estimated to be -- 1 x 10-9 in weight fraction. Concentration of 54Mn decreases toward the axial center in its axial profile, and radially is almost uniform inside and appreciably higher at free surfaces. An estimated Fe content of --10-8 in wight fraction is smaller by two orders of magnitude than that from chemical analysis. Higher concentraion of 60Co and 54Mn at the free surfaces suggests the importance of transportation process of these nuclides in the coolant loop. (author)

  15. 60Co gamma radiation effect on AlGaN/AlN/GaN HEMT devices

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-Ping; LUO Yin-Hong; WANG Wei; ZHANG Ke-Ying; GUO Hong-Xia; GUO Xiao-Qiang; WANG Yuan-Ming

    2013-01-01

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established.The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically,and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out.The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated,and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained.

  16. 60Co gamma radiation effect on AlGaN//AlN/GaN HEMT devices

    International Nuclear Information System (INIS)

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established. The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically, and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out. The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated, and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained. (authors)

  17. Resveratrol Effects on Life Span and Fertility of Caenorhabditis Elegans Subject to 60Co Gamma Ray Irradiation%白藜芦醇对60Coγ射线照射线虫寿命和生殖的影响

    Institute of Scientific and Technical Information of China (English)

    叶侃; 季晨博; 郭锡熔; 古桂雄

    2011-01-01

    Caenorhabditis elegans was used as experimental model to investigate radiation effect of resveratol on caenorhabdities elegans irradiated by 60Co γray. Treatment with resveratrol can increase average life span and spawning rate, improve the surrival rate of eggs, and protect their mitochondrion function of cacnorhabdities elegans exposure to 60Co rr ray. The results indicate that resveratrol has radiation protection effects, which might be related to its action on ROS decrease and mitochondrial defend.%以线虫作为实验模型,观察白藜芦醇(RES)对受60Coγ射线照射线虫的保护作用.结果表明,白藜芦醇能提高受照射线虫的寿命,增加产卵率,提高卵的存活率,保护其线粒体功能.其作用机制可能与白藜芦醇减轻氧自由基所致的线虫线粒体损伤有关.

  18. Performance of a Roos ionization chamber in gamma radiation beams ({sup 60}Co)

    Energy Technology Data Exchange (ETDEWEB)

    Perini, Ana P.; Neves, Lucio P.; Caldas, Linda V.E., E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Among the different types of dosimetry instruments, the ionization chambers are the most practical and and important radiation measurement devices due to their high sensitivity and relatively constant response within a wide range of energies. A commercial PTW ionization chamber (Roos electron chamber) usually utilized in X-ray beams, was tested to verify the possibility of its dosimetric application in {sup 60}Co beams. The main tests in this work were: short- and long-term stability, saturation, ion collection efficiency, polarity effect, leakage current and angular dependence. The characterization tests were performed using a Gammatron {sup 60}Co irradiator and a special goniometer made of PMMA. All results were within international recommendations. The reproducibility test presented results within the recommended limit of {+-}1%, and all coefficients of variation observed in the repeatability test were lower than {+-}0.07%. The ion collection efficiency was better than 99.9% for both polarities. For all pairs of polarity evaluated during the saturation test, the polarity effect was lower than the recommended limit. The maximum variation obtained for angular dependence test was only 0.5%. The chamber tested in this work achieved the expected results in the case of all pre-operational tests realized: stability, leakage current, angular dependence, saturation, ion collection and polarity effect. Evaluating the satisfactory results obtained, it is possible to indicate the usefulness of this ionization chamber for dosimetry in {sup 60}Co gamma radiation beams. (author)

  19. Seed germination of peanuts irradiated with cobalt ({sup 60}CO); Germinacao de sementes de amendoim irradiadas com cobalto ({sup 60}Co)

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Niedja Marrize C.; Almeida, Francisco de Assis C.; Gomes, Josivanda P.; Pessoa, Elvira B., E-mail: niedjamarizze@yahoo.com.b, E-mail: josivanda@deag.ufcg.edu.b, E-mail: elvirabe@gmail.co [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia Agricola; Leal, Artur S. Cavalcanti, E-mail: arturcleal@yahoo.com.b [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Dept. de Engenharia de Materiais

    2010-07-01

    This work was realized to evaluate the effect of gamma irradiation ({sup 60}Co) at doses 0, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00 and 4.00 kGy, on germination of seeds of peanut, cultivar BR1. Irradiation Department of Nuclear, UFPE, where he received after the irradiation, they were stored in packing of PET and polyethylene braided with a time of 90 days. Through the results, obtained monthly, concluded that the dose of 0.5 kGy was effective in the germination of seeds of peanut, not affecting its power of germination and overcoming the witness within 30 to 60 days. (author)

  20. Study of the effect of gamma irradiation ({sup 60} Co) on the quality of sugar cane spirit and on the cask of maturation; Estudo do efeito da irradiacao gamma ({sup 60} Co) na qualidade da cachaca e no tonel de envelhecimento

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Mariana Branco de; Horii, Jorge; Alcarde, Andre Ricardo [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept.de Agroindustria, Alimentos e Nutricao]. E-mails: jhorii@esalq.usp.br; aralcard@esalq.usp.br

    2006-10-15

    The ageing or maturing process of drink improves the sensorial characteristics of the product making it a qualified drink with higher economical value. The traditional maturing method of drinks involves their interaction with wood and irradiation can accelerate this ageing process. Sugar cane spirit and oak barrels with a 20 L capacity were treated using gamma irradiation (150 Gy). Physical-chemical and chromatographic analyses were constantly performed for 390 days during the drink ageing period. The sugar cane spirit and barrel irradiation did not change most volatile components of the same type coefficient such as volatile acidity, esters, superior alcohols and furfural throughout the 390 days. There is evidence, however, that some component parameters like aldehydes, tannin, color and copper concentration are in some way influenced resulting in partial acceleration of the ageing or maturing process. At the end of the ageing period, a sensorial analysis was made using 30 non-trained people who tasted the drink. The ageing process acceleration was confirmed by the sensorial evaluation, where the irradiated sugar cane spirit and/or barrel had higher approval regarding all parameters analyzed (scent, flavor and appearance). (author)

  1. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

    Energy Technology Data Exchange (ETDEWEB)

    Lucas de Oliveira, P.C.; Madruga, R.A.; Barbosa, N.P.U. [Uberaba School of Veterinary Medicine (UNIUBE), MG (Brazil)]. E-mail: pedrolucaso@uol.com.br; Sakate, M. [UNESP, Botucatu, SP (Brazil). School of Veterinary Medicine and Animal Husbandry

    2007-07-01

    Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from {sup 60}Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca) venom, natural and irradiated from a {sup 60}Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5 mg/kg of natural venom; and GIIV, inoculated with 0.5 mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase, aspartate amino-transferase and alanine amino-transferase; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom. (author)

  2. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

    Directory of Open Access Journals (Sweden)

    P. C. Lucas de Oliveira

    2007-01-01

    Full Text Available Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from 60Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca venom, natural and irradiated from a 60Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5mg/kg of natural venom; and GIIV, inoculated with 0.5mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase (CK, aspartate amino-transferase (AST and alanine amino-transferase (ALT; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom.

  3. Humoral immune response against native or 60Co irradiated venom and mucus from stingray Paratrygon aiereba

    International Nuclear Information System (INIS)

    Poisonings and traumas caused by poisonous freshwater fish such as rays are considered a major public health problem and draw attention because of accidents involving these animals cause serious local symptoms and are disabling, keeping the victim away from work. The therapy of these cases is based only on the symptoms of patients, which implies in its low efficiency, causing suffering for the victims. This study aims to evaluate and compare the humoral immune response in animals inoculated with native or 60Co irradiated Paratrygon aiereba venom and mucus. Ionizing radiation has proven to be an excellent tool to decrease the toxicity of venoms and isolated toxins. The mucus and venom samples of P. aiereba were irradiated using gamma rays from a 60Co source. Animals models were immunized with the native or irradiated mucus or venom. The assays were conducted to assess the production of antibodies by the immunized animals using enzyme immunoassay and western blotting. Preliminary results show the production of antibodies by the immunized animals. The resulting sera were also checked for antigenic cross- reactivity between venom and mucus, demonstrating the potential of mucus as an antigen for serum production for the specific treatment for accidents by stingrays. However, it is essential to carry out further tests in order to verify the neutralization of the toxin by antibodies formed by animals. (author)

  4. Biochemical and hematological study of goats envenomed with natural and 60Co-irradiated bothropic venom

    International Nuclear Information System (INIS)

    Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from 60Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca) venom, natural and irradiated from a 60Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5 mg/kg of natural venom; and GIIV, inoculated with 0.5 mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase, aspartate amino-transferase and alanine amino-transferase; clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom. (author)

  5. The radiation effect of 60Co gamma rays on polycarbonate detector

    International Nuclear Information System (INIS)

    The irradiation of polymeric materials with ionizing radiation (gamma rays, X rays, accelerated electrons, ion beams) leads to the formation of very reactive intermediates products (excited states, ions and free radicals), which result in rearrangements and/or formation of new bonds. The effects of these reactions are formation of oxidized products, grafts, scission of main chain (degradation) or cross-linking. Often the two processes (degradation - cross- linking) occur simultaneously, and the outcome of the process is determined by a competition between the reactions. Polycarbonate detectors are used as a particle track detector for neutrons and alpha particles detection. This work aims to study the ionizing radiation dose response of polycarbonate samples using spectrophotometric technique. A commercially available polycarbonate was analysed and its dosimetric characteristics were studied: radiation-induced absorption spectra, ambient light, temperature and humidity influence, pre- and post-irradiation stability, reproducibility and dose range useful response. Samples of polycarbonate (3 x 1 cm2) were irradiated with 60Co gamma radiation in free air at electronic equilibrium with absorbed doses between 1 and 95 kGy. When exposed to gamma radiation the polycarbonate detectors undergoes changes in their optical response, the colour variation is used for determining the absorbed dose. A Shimadzu UV-2101PC spectrophotometer was used for scanning the absorption spectra and measuring the optical density of film detectors irradiated with different radiation doses. Polycarbonate film detector are easy to prepare and to analyse, of good optical quality, inexpensive and of small size. The dosimetric accuracy can be affect by environmental conditions so, the detectors must be stored in appropriate conditions. The reproducibility of the detectors response can be improved by careful monitoring of optical densities before irradiation. The dose response curve presents linear

  6. Evaluation of fruit productivity and quality in Hass avocado submitted to 60Co gamma radiation

    International Nuclear Information System (INIS)

    Evaluation of productivity, postharvest behavior and fruit quality was performed on four years Hass avocado trees irradiated with 60 Co gamma rays in doses of 5, 10, 15, 20 and 25 Gy, established in the ''La Labor'' Experimental Center of the Centro de Investigaciones Cientificas y Tecnologias del Aguacate en el Estado de Mexico (CICTAMEX) at Temascaltepec Mexico. Productivity had a significant increase in the dose of 15 Gy being the average number of fruits nearly 400 % more than the control at fruit setting, being such difference reduced at fruit harvesting to 300 %. In regard to postharvest performance, the respiration index (mg CO2/kg/hr) did not show significant differences among treatments. Also others variables such as physiological weight losses, texture, maturity pattern, and sensorial tests (color, flavor, aroma, texture) were not different in regard to the control. This mean that radiation has altered productivity but not the quality and postharvest behavior of fruits. (Author)

  7. Manufacture of 60Co source irradiation facility and measurement of radiation filed

    International Nuclear Information System (INIS)

    60Co source radiation facility is an important equipment to produce reference radiation filed, according to national standard, the scattered dose rate must be less than 5% of the total dose rate in the reference radiation filed. Scattered radiation contribution and uniformity of reference radiation field are important parameters to describe the radiation performance of 60CO source irradiation device, Monte Carlo method was used to study the scattered radiation and uniformity of the reference radiation filed to provide theoretical basis for the design of 60CO source irradiating device in order to avoid economic losses caused by design mistakes. When 60CO source irradiating device was manufactured, PTW ionization chamber was used to measure the irradiation field. The results showed that the scattered radiation and uniformity of the radiation filed were in good agreement with the simulation results. The radiation performance met the design requirements. (authors)

  8. Biochemical and immunological alterations of 60 Co irradiated Bothrops jararacussu venom

    International Nuclear Information System (INIS)

    Proteins irradiation leads to structural alterations resulting in activity and function loss. This process has been useful to detoxify animal venoms and toxins, resulting in low toxicity products which increased immunogenicity. The Bothrops jararacussu venom behaves as a weak immunogen and its lethal activity in not neutralized by either autologous, heterologous or bothropic polyvalent antisera. This venom is markedly myotoxic and and the commercial bothropic antiserum does not neutralize this activity, because of this low immunogenicity of the myotoxins. This present work was done in order to evaluate the possibility of irradiating Bothrops jararacussu, intending to increase the immunogenicity of the myotoxic components, leading to productions of myotoxins neutralizing antibodies. Bothrops jararacussu venom samples were irradiated with 500, 1000 and 2000 Gy of 60 Co gamma rays. A 2.3 folds decrease of toxicity was observed for the 1000 Gy irradiated samples while the 2000 Gy irradiated sample was at least 3.7 folds attenuated. On the other hand, the 500 Gy did not promote any detoxification. Electrophoresis and HPLC data indicate that the irradiation lead to the formation of high molecular weight products (aggregates). The proteolytic and phospholipasic activities decreased in a dose dependent manner, the phospholipases being more resistant than the proteases. Both the animals (rabbit) immunized with either native or 2000 Gy irradiated venom produced native venom binding antibodies, a slightly higher titer being obtained in the serum of the rabbit immunized with the irradiated samples. Western blot data indicate that the anti-irradiated venom Ig Gs recognised a greater amount of either autologous or heterologous venom bands, both sera behaving as genus specific. The anti-native serum did not neutralize the myotoxic activity of native venom, while the anti-irradiated one was able to neutralize this activity. (author)

  9. Some gamma radiation (60Co) effects on Chrysomya megacephala (Fabricius, 1794) (Diptira-Calliphoridae)

    International Nuclear Information System (INIS)

    The effect of different gama radiation (60Co) doses on Chrysomya megcephala (Fabricius) have been studied under laboratory conditions, in the Entomology Section of Centro de Energia Nuclear na Agricultura (CENA-USP), Piracicaba, SP, Brasil. The insects were collected close to sucking animals brooding areas, identified and reared on artificial diet, being kept in a temperature (26 +- 20C) and humidity (66 +- 9%) controlled room, with 12L:12D photopheriod. A Gammabeam type 650 Cobalt-60 gamma irradiation source was used, with 28, 196x1010 Bq activity at the beginning of the experiment. The pupae were submitted to increasing gamma radiation doses. To determine lethal doses, treatments were carried out at four different ages and to determine the sterilizing doses two-three day pupae were used. It was noted pupae radiosensitivity decreased with age, LD50 varying from 14 - 513 Gy. The sterilizing dose for males was 40 Gy and for females 30 Gy. During the individuals life cycle, it was noted that there was a decrease in life expectancy (exo) of adults when the gamma radiation dose was increased. Treated males were more sensitive than females (Crossed with ''normals''), there occurring a marked reduction in the number of eggs and their viability when the used gamma radiation dose was increased. (author)

  10. Evaluation by EPR of potential antioxidant components of 60Co-irradiated varieties of soybean

    International Nuclear Information System (INIS)

    Brazil is today the second main producer of soybean in the world with a planted ground of about 21 million hectares and an annual production of 60 million tons in 2008, being slight more than a fourth of the annual production. The presence of flavonoids, particularly isoflavones in soybean products has been related as important for human health. It has been suggested that flavonoids play a role in the protection of plants by screening vital cellular components from damaging UV radiation. Electron paramagnetic resonance (EPR) spectroscopy can measure free radicals produced by dissociation molecules resulting from irradiation. It has been successfully employed for the detection of some irradiated food products. Twenty one Brazilian soybean cultivars from two crops were gamma-irradiated with a 60Co source and evaluated by EPR. Correlation coefficients were made among the central EPR signal (g = 2.0039) and the total and partial isoflavones contents. There was no correlation with total contents, though glicitein and acetyl-daidzin showed a negative correlation. Even 7 months after irradiation the intensity of central EPR signal were high enough to distinguish the irradiated samples. EPR measurements of separated parts of the grain were more efficient for that purpose, particularly from hilum and coat. The radiation did not change substantially the total isoflavone contents, although there were some evidences suggesting some conversion of glycosides to aglycones. (author)

  11. Detection of Argentine onions treated with 60 Co irradiation

    International Nuclear Information System (INIS)

    Brazil has been the most important MERCOSUL's purchaser of fresh onions from Argentina. The increased claim for this fresh product has forced a consensus between the members nations, as regards to phytosanitary restrictions. The radio inhibition is described on National Food Codes in Brazil and Argentina. Methods of food irradiation detection must be performed, since they increase the consumer confidence. Quick and simple screening tests indicate whether a food product has been irradiated or not. This present study verified the DNA fragments of argentine fresh onions, produced during radiation process and 6 months of storage period. The DNA fragments are analyzed for detection of irradiated foods. The irradiated onions presented extensive DNA migrations, as comets, when submitted to agarose gel electrophoresis. They also showed more shelf life compared to the unirradiated onions. The unirradiated samples exhibited only limited DNA migration. This initial screen method showed to be effective for detection of irradiated onions. (author)

  12. Manufacture of Single ~(60)Co Source Irradiation Facility

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Reference radiation filed produced by isotope source is necessary for calibration of radiation dose meter. According to the GB/T 12162.1-2002 "X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining

  13. Expression of FHIT in AHH-1 cells irradiated by 60Co γ-ray and bystander effect cells

    International Nuclear Information System (INIS)

    Objective: To investigate the expression of FHIT gene in the 60Co gamma-ray irradiated human lymphocytoblast (AHH-1) cell and the bystander effect cell, and to explore the function of FHIT gene in the bystander effect of ionizing radiation. Method: Preparation of bystander effect cell model: after inadiated with different dose of 60Co gamma-ray (0, 2, 5 Gy), the directly irradiated AHH-1 cells were collected immediately by centrifugation and co-cultivated with non-irradiated cells in Transwell, forming the bystander effect group P1. In addition, some culture media supematant of directly irradiated cells were transferred to the non- irradiated cells culture medium, forming the group P2. Then cells were collected at 0, 6, 12, and 24 h after irradiation and the total RNA and protein were extracted. RT-PCR and Western blot were performed to determine the FHIT mRNA and protein level, respectively. Flow cytometry assay and cell counting were conducted to detect the alteration of cell cycle and cell proliferation, respectively at 0, 24 h after irradiation. Results: The mRNA level of FHIT gene among control cells, directly irradiated cells and bystander cells showed no obvious difference, while the FHIT protein level of the directly irradiated cells and bystander cells was significantly down-regulated compared with the control cells (F=102.45, P2 phase arrest and obviously inhibited the proliferation ability. Conclusions: 2 and 5 Gy of 60Co γ-ray irradiated AHH-1 cells can result in down regulation of the FHIT protein expression, which suggests that FHIT gene is involved in the process of bystander effect induced by irradiation. (authors)

  14. Estudo do efeito da irradiação gamma (60CO na qualidade da cachaça e no tonel de envelhecimento Study of the effect of gamma irradiation (60co on the quality of sugar cane spirit and on the cask of maturation

    Directory of Open Access Journals (Sweden)

    Mariana Branco de Miranda

    2006-12-01

    Full Text Available O processo de envelhecimento ou maturação das bebidas proporciona uma melhora nas características sensoriais da cachaça, tornando-a de qualidade superior e de maior valor econômico. O método tradicional de maturação de bebidas é sua interação com madeiras, sendo que a irradiação pode acelerar este processo de envelhecimento. A cachaça e os tonéis de carvalho de 20 L de capacidade foram submetidos à irradiação gama (150 Gy. Análises físico-químicas e cromatográficas foram realizadas periodicamente ao longo de 390 dias do período de envelhecimento da bebida. A irradiação da cachaça e do tonel não alterou a maioria dos componentes voláteis do coeficiente de congêneres como acidez volátil, ésteres, álcoois superiores e furfural durante os 390 dias. Há evidências, entretanto, de que os parâmetros de alguns componentes como aldeídos, taninos, cor e teor de cobre são de alguma forma influenciados, resultando em aceleração parcial do processo de maturação ou envelhecimento. Ao final do período de envelhecimento, foi feita uma análise sensorial com 30 provadores não treinados. A aceleração do processo de envelhecimento foi confirmada pela avaliação sensorial, e a cachaça e/ou tonel irradiados receberam maior indicação de aprovação em todos os parâmetros analisados (aroma, sabor e aparência.The ageing or maturing process of drink improves the sensorial characteristics of the product making it a qualified drink with higher economical value. The traditional maturing method of drinks involves their interaction with wood and irradiation can accelerate this ageing process. Sugar cane spirit and oak barrels with a 20 L capacity were treated using gamma irradiation (150 Gy. Physical-chemical and chromatographic analyses were constantly performed for 390 days during the drink ageing period. The sugar cane spirit and barrel irradiation did not change most volatile components of the same type coefficient such

  15. Microstructural study of Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-x}/Ag samples irradiated with {sup 60}Co {gamma} rays at high doses

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, R. [Programa de Postgrado en Fisica de Materiales, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Apartado Postal 2681, CP 22800, Ensenada, BC (Mexico); Galvan, D.H. [CECIMAC-UNAM, Apartado Postal 2681, CP 22800, Ensenada, BC (Mexico); Adem, E. [Instituto de Fisica-UNAM, Apartado Postal 20-364, CP 01000, Mexico DF (Mexico); Bartolo-Perez, P. [CINVESTAV-IPN Unidad Merida, Departamento de Fisica Aplicada, Merida, Yucatan (Mexico); Maple, M.B. [Physics Department and Institute for Pure and Applied Physical Sciences, La Jolla, CA (United States)

    1998-06-01

    We have investigated the damage induced by irradiation in Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-x} silver added samples. The samples were prepared with 0 and 6.5 wt% of silver and irradiated by high-energy {gamma} irradiation (50-150 Mrad). The roles of silver and dosage irradiation are discussed in terms of their effects on microstructure, crystallinity, critical temperature (T{sub c}) and zero-resistance temperature (T{sub 0}). After irradiation, T{sub c} decreased while the room-temperature electrical resistance increased by a factor of 8 for some of the samples. The difference in T{sub 0} between irradiated and non-irradiated YBCO samples was of the order of 10 K. We have found that the difference is bigger for silver-added samples. We have also observed several changes in diffraction patterns of YBCO and YBCO-silver samples. SEM images, EDS and XPS analysis showed that silver resided inside the grains as single atoms and as metallic clusters. The relative concentrations of the elements in samples were quantified by Auger electron spectroscopy. The values showed a gradual increase for radiation doses ranging between 0 and 100 Mrad. For doses up to 100 Mrad, J{sub c} decreased because of the weak-link breakage induced by high doses of {gamma} rays. (author)

  16. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818 DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818

    Directory of Open Access Journals (Sweden)

    Elaine Barros da Costa CARVALHO

    1999-11-01

    Full Text Available The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30 = 218.2 Gy was found greater than in cross-fecundation forms. These data point to a low radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon.A variação da resistência entre indivíduos em autofecundação e fecundação cruzada de Biomphalaria glabrata foram estudadas. Uma população de 480 moluscos foi observada durante 29 dias, distribuída em 8 grupos de caramujos isolados e 8 grupos em colônias após a exposição (30 caramujos por grupo-dose a doses crescentes de radiação gama. Foram usadas doses de 10, 20, 40, 60, 80, 160, 320 e 640 Gy de um irradiador Gamma-Cell 60Co. Dois grupos não irradiados - isolado e colônia - foram separados como controle e após a irradiação todos os caramujos voltaram para aquários onde viviam antes. A sobrevida foi estimada pela contagem diária dos animais vivos em cada grupo-dose, a partir do dia da irradiação. O resultado mostrou maior sobrevivência nos grupos isolados (DL50/30 = 218.2 Gy que nos grupos

  17. Detection and thermoluminescence of coriander (Coriandrum sativum L.) irradiated with 60Co

    International Nuclear Information System (INIS)

    The fresh and dried coriander (Coriandrum sativum L.) is a spice of high commercial value as food for consumption in Mexico. Their hygienic quality is often poor due to some factors: contaminants present in irrigation water and the cultivation atmosphere, harvesting and post harvest handling, mainly. The process by radiation is an alternative to achieve the sterilization to adequate dose for the hygienic quality for its consumption. However, irradiation also involves food detection exposed to radiation. This paper presents detected results on the dried coriander that was obtained from fresh samples and thermoluminescent properties such as glow curves structure from low doses (0.5 Gy) to high (15 kGy), the dose response, thermoluminescent signal decay, in order to determine the loss of stability during the storage of the poly mineral fraction. We obtained the inorganic fraction separation of the organic part of particle sizes of 10 μm by the Zimmerman method. The samples were exposed at two dose ranges; 0.5-400 Gy and 0.5-15 kGy of gamma radiation with 60Co. The limit of thermoluminescent detection of the irradiated coriander samples was from 1 Gy. The glow curves were at a broad band of 35-400 C, with a maximum thermoluminescence around 182-196 C, and run at 164 C for high doses of 15 kGy. The range of linear response to dose was 4-25 Gy, whereas higher doses than the kGy order the response increase with the dose. The thermoluminescent properties of the coriander poly mineral fraction, show it can be used to identify irradiated food at gamma doses relatively low and even in doses of commercial interest due to the high stability of thermoluminescent signals. (Author)

  18. Determination of late-time Gamma-Ray (60Co) sensitivity of single diffusion Lot 2N2222A transistors.

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, Kendall Russell; Kajder, Karen C.; Peters, Curtis D. (American Staff Augmentation Providers, LLC, Albuquerque, NM)

    2008-08-01

    Sandia National Laboratories (SNL) has embarked on a program to develop a methodology to use damage relations techniques (alternative experimental facilities, modeling, and simulation) to understand the time-dependent effects in transistors (and integrated circuits) caused by neutron irradiations in the Sandia Pulse Reactor-III (SPR-III) facility. The development of these damage equivalence techniques is necessary since SPR-III was shutdown in late 2006. As part of this effort, the late time {gamma}-ray sensitivity of a single diffusion lot of 2N2222A transistors has been characterized using one of the {sup 60}Co irradiation cells at the SNL Gamma Irradiation Facility (GIF). This report summarizes the results of the experiments performed at the GIF.

  19. Detection and thermoluminescence of coriander (Coriandrum sativum L.) irradiated with {sup 60}Co; Deteccion y termoluminiscencia del cilantro (Coriandrum sativum L.) irradiado con {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz G, B. [Departamento de Agricultura y Ganaderia, Universidad de Sonora, 083190 Hermosillo, Sonora (Mexico); Cruz Z, E. [Unidad de Irradiacion y Seguridad Radiologica, Instituto de Ciencias Nucleares, UNAM, A. P. 70-543, 04510 Mexico D. F. (Mexico); Barboza F, M. [Centro de Investigacion en Fisica, Universidad de Sonora, A. P. 5-088, 083190 Hermosillo, Sonora (Mexico)

    2009-10-15

    The fresh and dried coriander (Coriandrum sativum L.) is a spice of high commercial value as food for consumption in Mexico. Their hygienic quality is often poor due to some factors: contaminants present in irrigation water and the cultivation atmosphere, harvesting and post harvest handling, mainly. The process by radiation is an alternative to achieve the sterilization to adequate dose for the hygienic quality for its consumption. However, irradiation also involves food detection exposed to radiation. This paper presents detected results on the dried coriander that was obtained from fresh samples and thermoluminescent properties such as glow curves structure from low doses (0.5 Gy) to high (15 kGy), the dose response, thermoluminescent signal decay, in order to determine the loss of stability during the storage of the poly mineral fraction. We obtained the inorganic fraction separation of the organic part of particle sizes of 10 {mu}m by the Zimmerman method. The samples were exposed at two dose ranges; 0.5-400 Gy and 0.5-15 kGy of gamma radiation with {sup 60}Co. The limit of thermoluminescent detection of the irradiated coriander samples was from 1 Gy. The glow curves were at a broad band of 35-400 C, with a maximum thermoluminescence around 182-196 C, and run at 164 C for high doses of 15 kGy. The range of linear response to dose was 4-25 Gy, whereas higher doses than the kGy order the response increase with the dose. The thermoluminescent properties of the coriander poly mineral fraction, show it can be used to identify irradiated food at gamma doses relatively low and even in doses of commercial interest due to the high stability of thermoluminescent signals. (Author)

  20. Changes in membrane receptors of B and T human lymphocytes exposed to 60Co gamma rays

    International Nuclear Information System (INIS)

    The present report describes the effect of 50 to 2500 rad of 60Co gamma rays on the membrane receptors of B and T lymphocytes. Surface membrane immunoglobulins and Fc receptors were used as markers for B cells, while the formation of rosettes with sheep red blood cells was used as a marker for T cells. The effect of radiation is expressed as the percentage of viable cells that bear membrane receptors. The radiation effects were studied after 2, 24, 36 hr of culture. For B lymphocytes no reduction in SmIg and Fc receptors was seen 2 hr after radiation, whereas a dose-related reduction was observed after 24 and 36 hr. A dose-related inhibition of the ''capping'' of SmIg was observed. For T lymphocytes a reduction of E rosette formation was seen starting 2 hr after irradiation. Electron microscopy of separated B and T cells showed a higher sensitivity of T cells as well as a different structural arrangement of the chromatin as a consequence of radiation damage. These data suggest differentiated behavior of B and T lymphocyte membrane receptors after exposure to radiation

  1. SV40 DNA amplification and reintegration in surviving hamster cells after 60Co γ-irradiation

    International Nuclear Information System (INIS)

    SV40-transformed Chinese hamster embryo cells were exposed to 60Co γ-irradiation and the fate of the integrated SV40 sequences was pursued over a period of 20 days following radiation exposure. As shown by colony hybridization, integrated SV40 sequences were amplified in surviving and non-surviving cells. At later times, however, clonal sublines of surviving cells grown for 20-30 cell generations after irradiation had lost most of their amplified SV40 copies but showed altered restriction fragment patterns indicating reintegration of SV40 sequences at new sites of the hamster genome. This suggest that 60Co γ-irradiation can generate mutations by inducing over-replication of chromosome segments that are then substrates of enzymatic rearrangements. (author)

  2. Effect of 60Co-γ ray irradiation on green coffee beans, 1

    International Nuclear Information System (INIS)

    Green coffee beans were irradiated with 60Co-γ rays at doses of 0, 0.05, 0.5, 5.0 and 10.0 Mrad and the changes of general components in green and roast coffee beans were investigated together with those of the organoleptic properties of roast beans during storage according to the cup testing. In case of Brazil santos beans, irradiation of some 0.05 Mrad 60Co-γ ray gave rather favourable mild flavour and no harmful influence on the quality of coffee, and moreover, would tend to extend the shelf life of roast beans. But influence of irradiation on the quality of coffee differed somewhat between two cultivars, Brazil santos and Colombia. (auth.)

  3. Viabilidade e micoflora de sementes de amendoim irradiadas com cobalto (60Co Viability and mycoflora of irradiated seeds of peanut with cobalt (60Co

    Directory of Open Access Journals (Sweden)

    Niédja M. C. Alves

    2011-03-01

    Full Text Available Estudou-se o efeito de diferentes doses da irradiação gama na germinação e percentagem de infecção fúngica em sementes de amendoim cultivar BR1. Inicialmente, as sementes foram avaliadas quanto à micoflora, utilizando-se o método de papel de filtro umedecido, a germinação em substrato de papel germitest e determinação do teor de umidade em estufa, a 105 ± 2 ºC. Posteriormente, as sementes foram submetidas à irradiação com uma fonte de 60Co, tipo gammacell, onde se estudou o efeito de 8 doses de irradiação na micoflora e germinação das sementes acondicionadas em embalagem de PET e polietileno trançado durante 60 dias de armazenamento, sem controle de temperatura e umidade relativa do ar. Os fatores estudados (doses em kGy, embalagens e tempo de armazenamento foram analisados em um delineamento inteiramente casualizado, dispostos em fatorial. Com base nos resultados, observou-se que a irradiação gama afetou negativamente a germinação das sementes de amendoim e que doses acima de 3,0 kGy comprometem a germinação das sementes. A radiação a partir da dose 1,5 kGy eliminou os fungos Aspergillus niger e, Penicillium a partir da dose de 2,5 kGy.The effect of different doses of the gamma irradiation was studied on germination and percentage of fungal infection in peanut seeds cultivar BR1. Initially the seeds were evaluated for the mycoflora using the method of humidified filter paper, the germination in paper substratum germitest and determination of the moisture content in oven at 105 ± 2 ºC. Later on the seeds were submitted to irradiation with a source of 60Co, type gammacell, where the effect was studied of 8 doses of irradiation in the mycoflora and germination of the seeds conditioned in PET packing and polyethylene tressed during 60 days of storage, without control of temperature and relative humidity of the air. The studied factors (doses in kGy, packing and time of storage were analyzed in a completely

  4. Multistep process of neoplastic transformation of normal human fibroblasts by 60Co gamma rays and Harvey sarcoma viruses

    Energy Technology Data Exchange (ETDEWEB)

    Namba, M.; Nishitani, K.; Fukushima, F.; Kimoto, T.; Nose, K.

    1986-03-15

    As reported previously (Namba et al., 1985), normal human fibroblasts were transformed by 60Co gamma-ray irradiation into immortal cells with abnormal karyotypes. These transformed cells (KMST-6), however, showed a low cloning efficiency in soft agar and no transplantability. However, upon treatment with Harvey murine sarcoma virus (Ha-MSV), the cells acquired elevated clonability in soft agar and transplantability in nude mice. Ha-MSV alone, however, did not convert normal human fibroblasts into either immortal or tumorigenic cells. The Ha-MSV-transformed KMST-6 cells showed an enhanced expression of the ras oncogene, but normal and 60Co gamma-ray-transformed cells did not. Our current data suggest that gamma rays worked against normal human cells as an initiator, giving rise to chromosome aberrations and immortality, and that Ha-MSV, probably through its ras oncogene, played a role in the progression of the malignant cell population to a more malignant one showing enhanced colony formation in soft agar and tumorigenicity in nude mice.

  5. Effect of gamma radiation of 60Co in the variability of chinese bean [Vigna unguiculata (l.) Walpers] en R4M4

    International Nuclear Information System (INIS)

    Selection of plants of Chinese bean coming from seed irradiated with gammas of 60Co in the generation R4M4 (fourth recurrent irradiation, fourth segregate generation) were carried out, taking as selection approaches the plant architecture, the numbers of sheaths for plant, sheath longitude, position of the sheaths, grain size and resistance to plagues and illnesses. 17 lines were selected for grain and 3 lines with fodder characteristics of black grain color were also obtained. (Author)

  6. Humoral immune response against native or {sup 60}Co irradiated venom and mucus from stingray Paratrygon aiereba

    Energy Technology Data Exchange (ETDEWEB)

    Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Aires, Raquel da Silva; Turibio, Thompson de Oliveira; Rocha, Andre Moreira; Spencer, Patrick Jack; Nascimento, Nanci do, E-mail: 0916@prof.itpacporto.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Seibert, Carla Simone, E-mail: carlaseibert@yahoo.com [Universidade Federal do Tocantins (UFT), Porto Nacional, TO (Brazil)

    2015-07-01

    Poisonings and traumas caused by poisonous freshwater fish such as rays are considered a major public health problem and draw attention because of accidents involving these animals cause serious local symptoms and are disabling, keeping the victim away from work. The therapy of these cases is based only on the symptoms of patients, which implies in its low efficiency, causing suffering for the victims. This study aims to evaluate and compare the humoral immune response in animals inoculated with native or {sup 60}Co irradiated Paratrygon aiereba venom and mucus. Ionizing radiation has proven to be an excellent tool to decrease the toxicity of venoms and isolated toxins. The mucus and venom samples of P. aiereba were irradiated using gamma rays from a {sup 60}Co source. Animals models were immunized with the native or irradiated mucus or venom. The assays were conducted to assess the production of antibodies by the immunized animals using enzyme immunoassay and western blotting. Preliminary results show the production of antibodies by the immunized animals. The resulting sera were also checked for antigenic cross- reactivity between venom and mucus, demonstrating the potential of mucus as an antigen for serum production for the specific treatment for accidents by stingrays. However, it is essential to carry out further tests in order to verify the neutralization of the toxin by antibodies formed by animals. (author)

  7. Effects of 60Co-γ ray irradiation on antioxidant enzyme activities in tobacco

    International Nuclear Information System (INIS)

    Effects of 300Gy 60Co-γ ray irradiation on the activities of 3 antioxidant enzymes in tobacco were studied in this paper. The results showed that the activities of superoxide dismutase (SOD), peroxidas (POD) and catalse (CAT) in tobacco were gradually increased. All the activities of SOD POD and CAT reached the maximums at 12 h and then gradually decreased. Similar results were also observed in the expression of sod, pod and cat genes. These results indicated that the activities of antioxidant enzymes could play an important role in tobacco tolerance against irradiation

  8. Effect of 60Co-irradiation on penicillin G procaine in veterinary mastitis products

    International Nuclear Information System (INIS)

    The effect of 60Co-irradation on penicillin G procaine in a peanut oil-based veterinary mastitis product was examined by reversed-phase high-performance liquid chromatography (HPLC). The HPLC method is capable of separating and quantifiying procaine, penicillin G, and various degradation compounds. Values obtained by the HPLC method on the product irradiated and stored at various temperatures correlated well with those of the microbiological assay. No significant decrease in the procaine was detected even after 4.0-Mrad irradiation. The HPLC method is applicable for analysis of other beta-lactam antibiotics

  9. Protective effect of gingerol on leucocyte and bone marrow DNA of 60Co γ-rays irradiated mice

    International Nuclear Information System (INIS)

    In this article, the effect of gingerol on peripheral leucocyte and bone marrow DNA of 60Co γ-rays irradiated mice was developed., Twenty-four healthy healthy female Kunming mice were randomly divided into 4 groups: control, gingerol, irradiation and gingerol + irradiation group. Gingerol group and gingerol + irradiation group were given gingerol intragastrically once a day for five days. Irradiation group and gingerol + irradiation group were suffered from 5 Gy 60Co γ-rays irradiation at the rate of 1.2 Gy/min on the 6th day. Blood samples, spleens, livers and thigh bones were collected to be measured after 48 h. The results showed that, compared with irradiation group, gingerol + irradiation group had significantly higher spleen index (p60Co γ-rays irradiated mice. (authors)

  10. Effects of testicular irradiation with 60Co in guinea pigs CAVIA PORCELLUS

    International Nuclear Information System (INIS)

    Improvements were made in restaint systems and in the technique of electroejaculation in guinea pigs, emphasizing safety, effectiveness and repetition. Arrangements for simultaneous testicular irradiation with 60Co in 5 animals and a phantom to test dose levels in the target region and scattering were also made. Effects of single and fractionated exposures on sperm were studied. A collimated point-shaped 60Co-machine calibrated to 7 R/min was used as radiation source. Groups of five 12 month aged male guinea pigs were exposed to either single testicular irradiation of 50, 100, 200 and 400 R or fractionated weekly testicular irradiation of 2, 5, 10 and 20 R, during 10 weeks. A last group was exposed to 4 fractionated testicular irradiations of 20 R at time intervals of 21 days and a group of 8 animals was used as control. Semen samples evaluations were made during 5 weeks before irradiation and in the subsequent 11 weeks. Abnormalities in sperm morphology were studied by William's method and phase contrast microscopy. Mean percentages of semen normal espermatzoons and spermatic abnormalities are shown in figures and photomicrographs. Marked differences on concentration, sperm motility and sperm abnormalities were found, but not on volume, in favour of 100 and 200 R single doses levels, as compared to fractionated 10 and 20 R. (Author)

  11. Effects of 60Co γ-rays irradiation on seed growth of ground-cover chrysanthemum

    International Nuclear Information System (INIS)

    The seeds of ground-cover chrysanthemum were used to study the effects of different doses of 60Co γ-rays irradiation(10-50 Gy) on seed germination and physiological characteristics. The results showed that the rate of seed germination and seedling survival decreased significantly with the irradiation doses. With the increase of irradiation dose to above 20 Gy, the content of malondialdehyde (MDA) and activity of peroxidase (POD) in seedlings significantly increased. The similar trends were found in the activities of superoxide dismutase (SOD) and glutathione reductase (GR). Catalase (CAT) activity increased at doses lower than 20 Gy, and then decreased at the higher doses, whereas ascorbate peroxidase (APX) activity did not alter except for 40 Gy. It is concluded that the suitable irradiation dose of mutation breeding is 20 Gy for the seeds of ground-cover chrysanthemum. Although 60Co γ-rays irradiation resulted in damage of membrane lipid peroxidation in the survival seedlings, the increased activity of CAT and POD could protect them against the damage. (authors)

  12. Dominant lethal effect of gamma radiation of 60Co in Biomphalaria glabrata (SAY, 1818)

    International Nuclear Information System (INIS)

    Germ cell mutations are used in ecotoxicological studies as biomarkers of population effects and indicators of ecological changes. Biomphalaria glabrata, a freshwater mollusk, is a good experimental model for biomonitoring studies due to its biological characteristics and the ecological importance of this invertebrate group. The dominant lethal test was established in B. glabrata for the detection of germ cell mutations. Results with chemical mutagens showed that this system is efficient, specific and sensitive in the evaluation of germ cell mutations induced by reference mutagens. In this work, the dominant lethal effects of gamma radiation of 60Co were studied. A preliminary experiment was done to establish the dose range and to estimate the chronology of spermatogenesis in B. glabrata. This estimate is possible because of the uniformity in response to ionizing radiation between germ cells at homologous stages of spermatogenesis in widely different species. In general, pre-meiotic germ cells are less sensitive to the induction of lethal dominant mutations than post-meiotic cells. This effect can be attributed to: young gametogenic cells - mitotically active - have greater repair ability from sub-lethal DNA damage and there is a selective elimination of the damaged cells. In our system: induction of lethal dominant mutations causes an increase in the frequency of malformations and, cytotoxic effect is displayed as a reduction in the crossing rates. Total duration of spermatogenesis was estimated in approximately 36 days, with the following distribution of stages: 1 to 13 days - spermatogonia, 14 to 20 days - spermatocytes, 21 to 36 days - spermatids and spermatozoa. Based on this chronology, irradiated wild-type snails with 2,5; 10 and 20Gy and crossed with non-irradiated albino snails after 7, 17, 23, 30 and 36 days. The frequencies of malformations in the heterozygous wild-type offspring of the nonirradiated albino snails were used as indicator of germ cell

  13. Use of {sup 60}Co gamma radiation in increased levels of total polyphenol extracts of bark of Schinus terebinthifolius Raddi

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo H.F.; Silva, Edvane B.; Silva, Hianna A.M.F.; Amorin, Elba L.C.; Peixoto, Tadeu J.S.; Yara, Ricardo; Lima, Claudia S.A., E-mail: santosghf@hotmail.com, E-mail: edvborges@yahoo.com, E-mail: amdemelo@hotmail.com, E-mail: claudia.salima@gmail.com, E-mail: ricardo.yara@gmail.com, E-mail: tadeu1903@yahoo.com.br, E-mail: elba@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2013-07-01

    Schinus terebinthifolius Raddi (Anacardiaceae) is well known as sources of phenolic compounds. Known as mastic pepper, red pepper tree is a plant native to midsize coast of Brazil. Some of its structures have proven antibacterial, anti-inflammatory, antifungal and healing. The aim of this study was to evaluate the difference in the phenol contents of crude extracts that were measured after irradiating the barks of S. terebinthifolius using gamma radiation from {sup 60}Co. The crude extract were divided into a control group and eight experimental groups, which were separated based on the doses of gamma radiation to which they were exposed: 2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 20.0 and 50.0 kGy (Assays were performed in triplicate). The results allow observe that gamma radiation promoted in extracts of bark of S. terebinthifolius, many percents increase (p> 0.05) of total polyphenol content between 2.5 kGy (41.93%) and 50.0 kGy (44.52%) compared to 0 kGy (30.07%), with the same gradual to 10.0 kGy, and reaching peak maximum at 10.0 kGy (68.44%). However, the study puts the process of gamma radiation from {sup 60}Co as an alternative significant increase in the percentage of some natural substances of plant material, and subsequently contribute to the augmentation of various therapeutic applications to which they are assigned. (author)

  14. Study on Several Characteristics of Agaricus blazei Murril Strain J3 Irradiated by 60Co

    Institute of Scientific and Technical Information of China (English)

    WENG Bo-qi; JIANG Zhi-he; HUANG Ting-jun; CHEN Jian; ZHENG Wei-wen

    2003-01-01

    A new mutant strain J3 from Agaricus blazei Murril was obtained by 60Co irradiation. The yields of successive generations were increased more than 70% to compare with their original strain. The component analysis on amino acids and fatty acid illuminated that the nutrient value of strain J3 fruiting body was better than the original strain. The apparent nodule structure was found in the hyphea of J3 strain through the observation by scanning electron microscope. RAPD analysis showed the great difference of PCR fingerprints between J3 and its original strain. It is a promising mutant strain for further commercial development in the future.

  15. Radiation-induced micronucleus formation in mice bone marrow after exposure to different doses of 60Co gamma radiation

    International Nuclear Information System (INIS)

    The frequency of micronuclei formation in the polychromatic erythrocytes and normochromatic erythrocytes was studied at 12 and 24th post-irradiation in mice bone marrow whole-body exposed to 0, 0.5, 1.0, 2.0, 3.0 and 4.0 Gy of 60Co gamma radiation. It was observed that the frequency of MPCE (micronucleated polychromatic erythrocytes) and MNCE (micronucleated normochromatic erythrocytes) increased with increase in exposure dose in both intervals studied. The data analyzed using the linear quadratic (Y+C+αD+βD2) equation. It was found that the data for MPCE and MNCE fitted best for linear quadratic model. (The PCE/NCE ratio declined with increase in exposure dose in both intervals and this decline was dose related. (author). 28 refs., 1 tab

  16. Study for optimization of a 60 Co industrial irradiator of 250 k Ci

    International Nuclear Information System (INIS)

    This work presents results of a benchmark between calculated and experimental absorbed dose values for a typical product, in a 60 Co industrial irradiator, located at ININ, Mexico. The goal of this work is to reach a ± 10 % approximation between both values. ININ 60 Co industrial irradiator is a two level, two layer system with overlapping product configuration, 56 irradiation positions with an activity of around 250 k Ci. Calculated values were obtained by QAD-CGGP code. This code uses a point kernel technique, build-up factors fitting was done by geometrical progression and combinatorial geometry was used for 3 D system description. Main code modifications were related with source simulation by punctual sources and energy spectrum (16 energy groups) and anisotropic emission were also considered. Experimental data were obtained from routine dosimetry which was done with red acrylic pellets; they were irradiated together the product in predetermined positions, for 36 maximum and minimum absorbed dose values. Typical product was polypropylene Petri dish packages, apparent density 0.13 g/cm3. It was chosen because regular geometry (2 packages per full irradiator container) and enough amount for considering homogeneous loading inside irradiation chamber. Required minimum dose was 15 kGy. Results showed a 8% variation between calculated and experimental values for maximum absorbed dose (18.2 kGy vs 16.8 kGy) and 3 % variation for minimum absorbed dose (13.8 kGy vs 14.3 kGy); these results fixed with the original proposal. (Author)

  17. 60Co irradiation for sterilization of veterinary mastitis products containing antibiotics and steroids

    Science.gov (United States)

    Tsuji, K.; Kane, M. P.; Rahn, P. D.; Steindler, K. A.

    Effects of 60Co irradiation for sterilization of veterinary mastitis products were evaluated. The mastitis products which were examined contained various combinations of antibiotics and steroids suspended in peanut oil vehicle. Bioburden data indicated that the unirradiated products were only occasionally contaminated with microorganisms. The D-values of the nonsterile product and environmental isolates were 0.028, 0.15, 0.017, and 0.018 Mrads for Aspergillus fumigatus, Penicillium oxalicum, Pseudomonas aeruginosa, and Pseudomonas maltophilia, respectively. The D-value of the biological indicator organism, Bacillus pumilus spores, in the vehicle was 0.27 Mrads. Thus, an irradiation dose of 1.6 Mrads would be sufficient to achieve six log cycles of destruction of the biological indicator organism. The minimum absorbed irradiation dose of 2.5 Mrads preferred by many countries for sterilization would achieve 9.3 log cycle destruction of the indicator organism and guarantee a probability of 1 × 10 -15 assurance for the most radio-resistant product isolate, Penicillium oxalicum. In order to examine short and long term chemical stabilities of active components, stability indicating high-performance liquid chromatographic (HPLC) methods for the determination of the following antibiotics and steroids were developed. They were: dihydrostreptomycin, neomycin, novobiocin, penicillin G, hydrocortisone acetate, hydrocortisone sodium succinate, and prednisolone. The rates of degradation and radiolytic degradation schemes for the majority of these compounds were elucidated. Formation of new compounds was not observed in these antibiotics and steroids upon 60Co irradiation. The compounds that increased by irradiation were inherently present in commercially available non-irradiated lots and/or can easily be formed by either acidic, basic, or thermal treatment.

  18. Studies on mutagenic activity of 60Co γ-ray irradiated rape pollen

    International Nuclear Information System (INIS)

    In the present study on disinfection, the rape pollen was irradiated with 2.5 kGy 60Co γ-ray. Micronuclei, sister chromatid exchanges (SCE) of bone marrow cells and chromosomal aberrations of meiotic cells in mice were used as an indicater of chromosomal damage to study the mutagenicity of irradiated rape pollen. The results are as follows: (1) The frequency of micronuclei in polychromatic erythrocytes is 2.00 per mille; nucleated cells is 0.8 per mille in control group. In the numbers of polychromatic erythrocytes and nucleated cells with micronuclei, there is no obviously difference in irradiated and unirradiated groups. (2) SCE incidence of control group is 2.01 ± 0.12/cell. No significant difference in the frequency of SCE exists between non-irradiated rape pollen and the control groups. But the frequency of SCE in irradiated rape pollen group (3000 mg/kg/day x 7) is 2.36 ± 0.12/cell; high dose group (6000 mg/kg/day x 7) is 2.96 ± 0.14/cell. In comparison with control group, there is a significant difference. (3) The chromatid breaks, fragments, and univalents in primary spermatocytes have been obseved. The frequencies of chromosomal aberration showed no obviously difference among irradiated and non-irradiated rape pollen groups

  19. 60CoIrradiation Affects the Enzymatic Antioxidant System of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae)

    OpenAIRE

    Ke Zhang; Zhibin Li; Shaowen Zhu; Qunfang Weng

    2014-01-01

    Radio-(60Co), which emits γ rays, has been used worldwide in pest control. The aim of the present study was to analyze the effect of effective-low-power 60Coirradiation on the enzymatic antioxidant system of the citrus red mite Panonychus citri. One day old female adults were exposed to 0.4 kGy 60Coirradiation and on the, 6th h, 1st day, 2nd day, and 5th day post treatment, the mites were euthanized for biochemical analysis. The activity of superoxide dismutase (SOD), catalase (CAT), p...

  20. Primary Observations on the Influence of 60Co Local Irradiation on Free Skin Flaps

    Institute of Scientific and Technical Information of China (English)

    杨建荣; 张园

    2002-01-01

    Objective To study the effect of postoperative radiation on free skin flaps.Methods Twenty-nine patients with free skin flaps applied to the plerosis of the postoperative defectwere followed up. Twenty-eight out of 29 patients received forearm free flaps while 1 had anterolater-al femoris skin flaps in a size ranging from 14 cm× 6 cm to 8 cm× 4 cm. These flaps were exposedto 60Co radiation ranging 40-69 Gy. Results Observation during irradiation: no visible changes ofskin flaps and oral mucous membrane were detected when irradiation dose was within 40 Gy; somechanges may be detected over 40 Gy. Observation 1 - 4 months after irradiation: pigmentations werefound in areas of erosion epidermis; skin flaps got dark but without evidence of necrosis. Observation2 years after irradiation: no necrosis happened in 29 skin flaps. Hairs were found on 15 of 29flaps. Sensation occurred within the margin of 1 cm. Conclusion Free skin flap can endure irradi-ation at the dose of 60 Gy.

  1. Effect of gamma radiation of {sup 60}Co in the variability of chinese bean [Vigna unguiculata (l.) Walpers] en R{sub 4}M{sub 4}; Efecto de la radiacion gamma de {sup 60}Co en la variabilidad de frijol chino [Vigna unguiculata (l.) Walpers] en R{sub 4}M{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Salmeron E, J.; Bueno J, J.E.; Valencia E, F. [CSAEGro, Iguala, Guerrero, Tel and Fax 01 733 (33) 24328 (Mexico); Cervantes S, T. [IREGEP (Mexico); Cruz T, E. De la [ININ, Departamento de Biologia, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: csaegro@prodigy.net.mx

    2007-07-01

    Selection of plants of Chinese bean coming from seed irradiated with gammas of {sup 60}Co in the generation R{sub 4}M{sub 4} (fourth recurrent irradiation, fourth segregate generation) were carried out, taking as selection approaches the plant architecture, the numbers of sheaths for plant, sheath longitude, position of the sheaths, grain size and resistance to plagues and illnesses. 17 lines were selected for grain and 3 lines with fodder characteristics of black grain color were also obtained. (Author)

  2. Proteomics study of progeny of normal human liver cells irradiated by 60Co γ-rays

    International Nuclear Information System (INIS)

    Objective: To characterize the differential protein expression in the progeny of human liver cells surviving from ionizing radiation by the proteomic analysis. Methods: Two-dimensional electrophoresis gel coupled with mass spectrometry was used to explore the specific protein expression in the progeny of 7702 human liver cells surviving from ionizing radiation. Alterations in expression level of protein spots between the control and the progeny groups were statistically analyzed by ImageMaster 2D Platinum software and mass spectrometry was used to identify the protein spots with significantly altered expression-level. Results: The progeny of irradiated ceils were derived from human liver cell line exposed to 0, 2, 4, 6 Gy of 60Co γ-irradiation. A total of 42 differentially expressed proteins between the control and the progeny of the irradiated cells groups were screened, of which 17 were identified by matrix assistant laser desorption ion-top off light-mass spectrometry (MALDI-TOF MS) analysis, including 4 up-regulated and 13 down-regnlated proteins. Conclusions: The differentially expressed proteins profile could be significantly altered in the progeny of irradiated cells. The proteomics approach has the potential to detect the protein changes relevant to radiatian-induced genomic instability (RIGI). Further study of differentially expressed proteins would likely reveal the molecular mechanisms of gene expression in RIGI. (authors)

  3. Decomposition of ρ-nonylphenols in water by 60Co γ-ray irradiation

    International Nuclear Information System (INIS)

    ρ-Nonylphenols (NPs), one of endocrine disrupting chemicals, are used as plastic flexibilizers or nonionic surfactants, and widely released into the water environment. Hydroxyl radicals produced from water molecules by γ-ray irradiation have high oxidation reactivity. Recently, treatments with the hydroxyl radicals have drawn much attention to conserve the water environment. In this study, decompositions of NPs in water were investigated using hydroxyl radicals by 60Co γ-rays irradiation. The concentrations of the NPs at initial concentration from 45 to 1000 nM were decomposed by γ-ray irradiation. Qualitative and quantitative analyses of NPs were carried out by high performance liquid chromatography. The decomposition curves of NPs at each initial concentration were analyzed as single exponential functions. Alkylphenol activity of aqueous NPs solution, which was estimated by enzyme-linked immunosorbent assay, implies the irradiation products have alkylphenol activity. Two products having molecular weight of 236 were investigated by liquid chromatography-mass spectrometry, and were considered to be ρ-nonylcatechol and 1-(ρ-hydroxyphenyl)-1-nonanol on the basis of the oxidation mechanisms of ρ-cresol and 4-ethylphenol. (author)

  4. Effects of 60Co γ-ray irradiation on growth characters of Chamaecrista seeds

    International Nuclear Information System (INIS)

    The seeds of 5 Chamaecrista varieties were irradiated by 60Co γ-ray of 300 Gy and the effects on M1 generation were studied. The results showed that the emergence of 5 Chamaecrista varieties decreased in some degree ; the stem-length of variety 34721 was significantly decreased, the stem-diameter of variety 2219 and the leaf-width of variety 2219 were significantly increased. The number of branch, leaf and leaf-length had no significant difference, but there were many black blots in the leaf during early period; the dry-weight of aerial part changed in two directions, either increased (92985) or decreased (34721). The total N of variety 2217 were significantly increased and the total P of variety 92985 were significantly decreased. The squaring stage, initiate flower stage, full bloom stage, pod-bearing stage, peak pod setting stage and maturing stage had changed in two direction, either early, or late

  5. Effects of 60Coirradiation sterilization and influence on the quality of paprika powder

    International Nuclear Information System (INIS)

    The pollution of paprika powder was investigated and effects of gamma irradiation on the sterilization and quality were studied. The results showed that paprika powder was seriously polluted and gamma irradiation reduced significantly the total population of mesophilic bacteria, coliforms, lactobacillus, micrococcus, mould and spore. The mortality rate could reach 82%-94% at 2.62 kGy. There was no significant different between three kinds of packaging. The D10 va1ue of coliforms was 2.05-3.21 kGy, which were sensitive to irradiation and were the indicating bacteria of radiation dose setting. The lightness and yellowness of paprika powder decrease at high does, but total color difference and ASTA value had no significant difference, and the same to pungency by Scoville Test. So irradiation sterilization was perfect way to improve the quality paprika powder. (authors)

  6. 60Co irradiation for sterilization of veterinary mastitis products containing antibiotics and steroids

    International Nuclear Information System (INIS)

    Effects of 60Co irradiation for sterilization of veterinary mastitis products were evaluated. The mastitis products which were examined contained various combinations of antibiotics and steroids suspended in peanut oil vehicle. Bioburden data indicated that the unirradiated products were only occasionally contaminated with microorganisms. The D-values of the nonsterile product and environmental isolates were 0.028, 0.15, 0.017, and 0.018 Mrads for Aspergillus fumigatus, Penicillium oxalicum, Pseudomonas aeruginosa, and Pseudomonas maltophilia, respectively. The D-value of the biological indicator organism, Bacillus pumilus spores, in the vehicle was 0.27 Mrads. Thus, an irradiation dose of 1.6 Mrads would be sufficient to achieve six log cycles of destruction of the biological indicator organism. The minimum absorbed irradiation dose of 2.5 Mrads preferred by many countries for sterilization would achieve 9.3 log cycle destruction of the indicator organism and guarantee a probability of 1 x 10-15 assurance for the most radio-resistant product isolate, Penicillium oxalicum. In order to examine short and long term chemical stabilities of active components, stability indicating high-performance liquid chromatographic (HPLC) methods for the determination of several of the antibiotics and steroids were developed. The rates of degradation and radiolytic degradation schemes for the majority of the compounds were elucidated. (author)

  7. Evaluation of gamma-sterilization ({sup 60}Co) by RT-PCR by DHFR expression detection

    Energy Technology Data Exchange (ETDEWEB)

    Converso, Ana Paula G.; Andrade Junior, Heitor F. de [Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil)]. E-mail: anapaulagconverso@gmail.com; hfandrad@usp.br; Vieira, Daniel P. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil); E-mail: dperezv@usp.br

    2007-07-01

    The improvement of techniques to detect pathogen agents in blood had reduced significantly the contamination mechanisms by hemocomponents in blood transfusion procedures. Ionizing radiation is a method that has presented several applications on medicine and in currently days has been showing special attention on blood banks which has been applied to avoid TA-GVHD development. DHFR is an enzyme constitutive in Plasmodium protozoa and has an important role in folate metabolism on these parasites. Detecting the expression of RNAm coder for this enzyme is possible to evaluate the viability of this parasite in blood samples. Plasmodium chabaudi AJ is a parasite that induces lethal malaria in rodents similar to human malaria In this work, the objective was to detect the presence of plasmodium protozoa in irradiated blood samples, infected experimentally, through the application of a RT-PCR using primers for the coder sequence of DHFR's mRNA. We studied doses of ionizing radiation between 0 and 75 Gy. The irradiation procedures were accomplished in Center of Radiation Technology of IPEN-CNEN in a {sup 60}Co panoramic source. Our results had demonstrated that RT-PCR is a sensible method to evaluate the viability of plasmodium in blood samples because the technique could detect low parasite burden in all tested samples. (author)

  8. Characterization of 60Co and 137Cs beams from irradiator Shepherd 81 - 14D of LNMRI/IRD in radiation protection

    International Nuclear Information System (INIS)

    The objective of this work is the characterization of 60Co beams and the 137Cs irradiator Shepherd 81-14D acquired by the National Metrology Laboratory of Ionising Radiation of the Institute of Radiation Protection and Dosimetry (LNMRI /IRD), for use in calibration of measuring instruments of gamma radiation in air kerma and ambient dose equivalent, irradiation of films and TLD's. Field homogeneity measurements were carried out, calculated input and output time of the source and commissioning of sources. (author)

  9. Effects of 60Co gamma radiations on the conduction properties of frog sciatic nerve

    International Nuclear Information System (INIS)

    The effect of Co60 gamma radiations on the amplitude, detection period and duration of the action potential of sciatic nerves of Rana tigrina frogs have been studied. Dose levels of upto 120 kR were employed. Irradiation of the nerves with dose levels upto 30 kR does not seem to affect the action of potential profiles. The amplitude falls rapidly thereafter, registering less than 5% of the original value after irradiation by a dose of 120 kR. Qualitatively similar behaviour is seen in the case of detection period and duration of action potential. These results are examined in the light of data already collected through experiments on the effect of Co60 gamma rays on the enzyme acetyl-cholinesterase (AchE). (author)

  10. Evaluation by EPR of potential antioxidant components of {sup 60}Co-irradiated varieties of soybean; Avaliacao por RPE de componentes com potencial antioxidante de variedades de soja irradiadas com {sup 60}CO

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcos Ronaldo Ramos de

    2009-07-01

    Brazil is today the second main producer of soybean in the world with a planted ground of about 21 million hectares and an annual production of 60 million tons in 2008, being slight more than a fourth of the annual production. The presence of flavonoids, particularly isoflavones in soybean products has been related as important for human health. It has been suggested that flavonoids play a role in the protection of plants by screening vital cellular components from damaging UV radiation. Electron paramagnetic resonance (EPR) spectroscopy can measure free radicals produced by dissociation molecules resulting from irradiation. It has been successfully employed for the detection of some irradiated food products. Twenty one Brazilian soybean cultivars from two crops were gamma-irradiated with a {sup 60}Co source and evaluated by EPR. Correlation coefficients were made among the central EPR signal (g = 2.0039) and the total and partial isoflavones contents. There was no correlation with total contents, though glicitein and acetyl-daidzin showed a negative correlation. Even 7 months after irradiation the intensity of central EPR signal were high enough to distinguish the irradiated samples. EPR measurements of separated parts of the grain were more efficient for that purpose, particularly from hilum and coat. The radiation did not change substantially the total isoflavone contents, although there were some evidences suggesting some conversion of glycosides to aglycones. (author)

  11. Investigation of the /sup 59/Co(n,. gamma. )/sup 60/Co reaction with unpolarized and polarized neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Kopecky, J. (Stichting Energieonderzoek Centrum Nederland, Petten. Nuclear Structure Group); Delfini, M.G. (Stichting Energieonderzoek Centrum Nederland, Petten. Nuclear Structure Group; Rijksuniversiteit Utrecht (Netherlands). Fysisch Lab.); Chrien, R.E. (Brookhaven National Lab., Upton, NY (USA))

    1984-10-15

    Capture of 24 keV neutrons and polarized as well as unpolarized thermal neutrons in /sup 59/Co has been investigated. Of the 350 ..gamma..-rays observed 335 could be placed in a /sup 60/Co level scheme containing 144 levels. The reaction Q-value amounts to 7491.92(8) keV. The chi/sup 2/ analysis of the circularly polarized ..gamma..-rays results in 31 unambiguous spin assignments for /sup 60/Co levels. The fraction of the J=4/sup -/ channel in the thermal capture was determined to be (80 +- 1)%. An average ..gamma..-ray multiplicity of 2.3 gammas per neutron capture was observed. The resulting level scheme is compared to shell-model predictions. Possible reaction mechanisms are discussed.

  12. Evaluation of fruit productivity and quality in Hass avocado submitted to {sup 60}Co gamma radiation; Evaluacion de productividad y calidad de fruta en aguacate Hass sometido a radiacion gamma de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Cruz T, E. De la; Ibanez P, J.; Mijares O, P.; Garcia A, J.M. [Instituto nacional de Investigaciones Nucleares, Departamento de Biologia, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    Evaluation of productivity, postharvest behavior and fruit quality was performed on four years Hass avocado trees irradiated with {sup 60} Co gamma rays in doses of 5, 10, 15, 20 and 25 Gy, established in the ''La Labor'' Experimental Center of the Centro de Investigaciones Cientificas y Tecnologias del Aguacate en el Estado de Mexico (CICTAMEX) at Temascaltepec Mexico. Productivity had a significant increase in the dose of 15 Gy being the average number of fruits nearly 400 % more than the control at fruit setting, being such difference reduced at fruit harvesting to 300 %. In regard to postharvest performance, the respiration index (mg CO{sub 2}/kg/hr) did not show significant differences among treatments. Also others variables such as physiological weight losses, texture, maturity pattern, and sensorial tests (color, flavor, aroma, texture) were not different in regard to the control. This mean that radiation has altered productivity but not the quality and postharvest behavior of fruits. (Author)

  13. Effects of 60Co gamma radiation on defense function of human polymorphonuclear leukocytes

    International Nuclear Information System (INIS)

    The effects of radiation on defense function of polymorphonuclear leukocytes (PMN) were studied following irradiation with 60Co γ radiation (30 - 3,000 rad) using PMN separated from the peripheral blood of healthy volunteers. The migration distances for all three measures of chemotaxis to fMet-Leu-Phe (10-8 M), chemokinesis induced by fMet-Leu-Phe, and random migration tended to decrease with increasing dose, showing 0.0054 μm/rad (p -5 M) in conjunction with cytochalasin B (CB, 5 μg/ml) there was a significant dose trend, showing the dose effects of decreasing 0.0022 % release/rad for BGL and 0.0030 % release/rad for LYZ with increasing dose. In superoxide anion (O2-) production, a slight and marginally significant linear dose trend was found. These results suggest that the defense function of PMN is not so resistant to radiation as predicted from the fact that PMN in the peripheral blood are differentiated and mature. It is thought that radiation inflicts substantially harmful effects on the defense function of peripheral PMN. (author)

  14. Use of 60 Co gamma radiation to expend the shell life of packaged sliced loaves

    International Nuclear Information System (INIS)

    The evaluation of conservation of sliced loaves (bread cut into slices). baked by five bakeries of Piracicaba, after gamma irradiation and maintained into polyethylene begs of low density, of 47,5 and 85 μm of thicknesses is shown. The sliced loaves were put into the bags and thermo-sealed by hand, like they were handled by the bakers. After this, they were irradiated with doses of 0.0: 2.0; 4.0; 6.0; 8.0 and 10.0 kGy of gamma radiation in a irradiation chamber of Cobalt-60 at a dose rate of 2,68 kGy per hour, at the room temperature (280 C). After irradiation the samples were maintained under at the room temperature (26 - 340 C), and humidity, as similar as possible to the conditions of the markets, bakeries and shops they were sold. The samples were evaluated every days and if any of them presented sign of contamination. It was threw away because it was inappropriate for human consumption. (author)

  15. Effects on agronomic traits of M1 by pollen of upland cotton irradiated by 60Co-γ ray

    International Nuclear Information System (INIS)

    [Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-? Ray of varied doses. [Method] Ripe pollen grains of upland cotton were irradiated by 60Co-γ Ray with doses of 5, 10, 15, and 20 Gy, respectively, to learn radiation effect and select appropriate dose. [Result] Most properties of M1 obviously showed variation when dose was over 10 Gy; vitality, growth, and fertility were greatly inhibited when dose was 15 Gy which was almost semi-lethal concentration, and variation species were richest at the same time, which provided materials for practical breeding. [Conclusion] 60Co-γ Ray of 15 Gy was more suitable for inducing research for ripe pollen grains of upland cotton

  16. Obtained and evaluation of antisera raised against irradiated crotalic whole venom or crotoxin in 60 Co source

    International Nuclear Information System (INIS)

    Snake bite is a great Public Health problem in our country. The accidents with snakes from Crotalus genus are the most severe. About 1% of the victims die without seratherapy. The antivenons are obtained from hyper immune horse plasma. During the production these animals present signs of envenoming that result in a decrease of organic resistance besides the horses maintenance is very expensive and the producers are fewer, so the sera production is restrict. Many techniques which could reduce the venoms toxicity and increase the sera production using chemical and physical agents have been studied. The gamma rays are excellent tool to detoxify venoms and toxins. It is able to modify protein structures that decrease lethally, toxic and enzymatic activities without modifying the immunogenicity. So, it is important evaluate the sera production in rabbits using gamma rays detoxified venom and crotoxin as immunogen and their power as reagents in immuno assays. In order to obtain the antisera, Crotalus durissus terrificus whole venom or isolated crotoxin was irradiated with 2.000 Gy in 60 Co source, in a 150 mM NaCl solution, and inoculated in rabbits. The sera production were screened by immunoprecipitation, immuno enzymatic (ELISA) and immunoradiometric (IRMA) assays. The specificity was studied by immuno-electrophoresis, ELISA and western blot techniques. The neutralizing power was evaluated by neutralization of phospholipase A2 activity of toxin in vitro. The antisera were used as reagents in antigen capture assays ELISA and IRMA immuno assays to detect circulant antigens in sera of mice experimentally inoculated with crotalic venom or crotoxin. The results showed that both detoxified venom or crotoxin were good immunogens, and they were able to induce antibodies that could recognize non-irradiated venom or isolated crotoxin. The data suggest that those antibodies present more specificity and higher in vitro neutralizing power, when compared with commercial

  17. Efficacy of a 60Co irradiated vaccine for experimentally infected calves with dictyocaulus viviparus

    International Nuclear Information System (INIS)

    Dictyocaulus viviparus larvae in non-infected stage (L.1) were cultured in vitro to their infective stage (L.3) and were irradiated with 40 Krad from 60Co and used as a vaccine. The oral experimental vaccine dose was 1000 L.3/animal. Three groups were formed with 8 calves in each one: group No. 1 and group No. 2 were vaccinated at 10 weeks of age. Four weeks later group No. 1 was infected with non-irradiated 60 L.3/Kg. of animal weight 'challenge dose'. After four weeks of post-vaccination group No. 2 was revaccinated and 4 weeks later it was infected with the 'challenge dose' as the previous group. Eight calves constituted group No. 3, four in each group; they were infected with only the challenge dose respectively. Information data on respiratory and cardiac frequency, temperature, weight, and L.1 count/g. of feces were obtained from each animal three times a week. After five weeks of post-challenge all animals were slaughtered to observe anatomopathologic lessions in the heart and lungs; the number of adult Dictyocaulus viviparus present in the respiratory tract were search 't'. Student test was used for the statistical analysis. The weight increment difference between animals of group No. 1 related control group was 7Kg.; and 11.25 Kg/animal in group No. 2 respectively. The percentage of protection confered by the vaccine to the subjects in group No. 1 relative to the respectivecontrol group, was 83.2; that for the group No. 2 was 88.5 per cent. Post-morten examination revealed severe anatomopathologic lessions in the control groups; only few lessions were observed in group No. 1 and practically none in group No. 2

  18. 60CoIrradiation Affects the Enzymatic Antioxidant System of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae

    Directory of Open Access Journals (Sweden)

    Ke Zhang

    2014-05-01

    Full Text Available Radio-(60Co, which emits γ rays, has been used worldwide in pest control. The aim of the present study was to analyze the effect of effective-low-power 60Coirradiation on the enzymatic antioxidant system of the citrus red mite Panonychus citri. One day old female adults were exposed to 0.4 kGy 60Coirradiation and on the, 6th h, 1st day, 2nd day, and 5th day post treatment, the mites were euthanized for biochemical analysis. The activity of superoxide dismutase (SOD, catalase (CAT, peroxidase (POD, phenoloxidase (PO and acetylocholinesterase (AchE were investigated. POD and CAT activities, as well as SOD were higher in the irradiated mites. We found that exposure to 60Co-γ radiation resulted in increased activities of SOD, CAT, POD and decreased AchE activity. When the recovery time lasted till the 5th day, the activities of POD and PO were significantly lower than the control, whereas the SOD, CAT and AchE activities returned to control levels. Cells possess protein repair pathways to rescue oxidized proteins and restore their functions, but if these repair processes fail, oxidized proteins may become cytotoxic. Our results confirm the hypothesis that low dosages of 60Coirradiation increase the level of oxidative stress in P. citri adults in a short time, causing meanwhile damage and sterility. The results of this study also indicate that stress caused by exposure to irradiation could inhibit the cholinergic system in P. citri.

  19. (60)Coirradiation affects the enzymatic antioxidant system of the citrus red mite Panonychus citri (Acari: Tetranychidae).

    Science.gov (United States)

    Zhang, Ke; Li, Zhibin; Zhu, Shaowen; Weng, Qunfang

    2014-01-01

    Radio-(60Co), which emits γ rays, has been used worldwide in pest control. The aim of the present study was to analyze the effect of effective-low-power 60Coirradiation on the enzymatic antioxidant system of the citrus red mite Panonychus citri. One day old female adults were exposed to 0.4 kGy 60Coirradiation and on the, 6th h, 1st day, 2nd day, and 5th day post treatment, the mites were euthanized for biochemical analysis. The activity of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), phenoloxidase (PO) and acetylocholinesterase (AchE) were investigated. POD and CAT activities, as well as SOD were higher in the irradiated mites. We found that exposure to 60Co-γ radiation resulted in increased activities of SOD, CAT, POD and decreased AchE activity. When the recovery time lasted till the 5th day, the activities of POD and PO were significantly lower than the control, whereas the SOD, CAT and AchE activities returned to control levels. Cells possess protein repair pathways to rescue oxidized proteins and restore their functions, but if these repair processes fail, oxidized proteins may become cytotoxic. Our results confirm the hypothesis that low dosages of 60Coirradiation increase the level of oxidative stress in P. citri adults in a short time, causing meanwhile damage and sterility. The results of this study also indicate that stress caused by exposure to irradiation could inhibit the cholinergic system in P. citri. PMID:24853454

  20. Strand breaks and lethal damage in plasmid DNA subjected to 60CO-γirradiation

    International Nuclear Information System (INIS)

    Experiments with calf thymus DNA subjected to extracellular irradiation yield information on the role of direct and indirect effects in single-strand breakage, if this is evaluated with reference to the scavenger activity in respect of OH radicals. The role of the two processes in the occurrence of double-stand breaks and further damage leading to cell decay has so far remained largely obscure. It was the aim of the study described here to contribute to research in this field by performing in vitro experiments on biologically active DNA. For this purpose, DNA from pBR322 plasmids was irradiated in the presence of OH-radical scavengers. The number of single-strand and double-strand breaks was determined on the basis of the system's ability to eliminate OH radicals. In order to asses the influence of irradiation processes on the biological activity of DNA, investigations were carried out in E. coli for transformations caused by irradiated plasmid DNA. The results were interpreted in the light of theories about inhomogenous reaction kinetics put forward by Mark et al. (1989). It was finally discussed, which of the gamma-irradiation injuries occurring in DNA was to be held responsible for the inactivation of plasmid DNA and which enzymatic processes were additionally at work here. (orig./MG)

  1. {sup 60}Co irradiation effect on color in minimally processed cauliflower (Brassica spp)

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Santillo, Amanda G.; Villavicencio, Anna L.C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: thaisecfnunes@hotmail.com; Michels, Robert [Hydrofarm Comercio e Representacao de Produtos Agricolas Ltda., Sao Roque, SP (Brazil); Pitombo, Ronaldo N.M. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Alimentos e Nutricao Experimental

    2009-07-01

    Irradiation is a well-established process with clearly documented safety and efficacy. Consumers require a quality product that is convenient and has fresh-like characteristics and take product appearance, like color, into consideration as a primary criterion; it is considered a key role in food choice, food preference and acceptability. The objective of the present work was to investigate color degradation of cauliflower treated with gamma radiation during 14 days. Cauliflower irradiated samples with 0 and 1.5 kGy showed significant differences for value 'L' on the 10th and 14th day, respectively for value 'b' only the 0 kGy sample showed significant difference on day 10 of storage. On day 10 of shelf-life the irradiated cauliflower with doses of 1 and 1.5 kGy became more yellow compared to the control. The authors concluded that the treatment with low gamma radiation doses keeps the quality of fresh-cut vegetables. (author)

  2. Response of S. boulardii cells to {sup 60} Co irradiation and heat shock

    Energy Technology Data Exchange (ETDEWEB)

    Neves, M.J.; Andrade, A.S.R.; Santos, R.G. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Nicoli, J.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. Microbiologia

    1997-12-31

    Full text. Preparation of Saccharomyces boulardii, a non pathogenic yeast, has been widely used in Europe and other countries to prevent gastrointestinal disorders. However the mechanism of action of theses cells on the illness is unknown but the efficacy of S. boulardii depends on its viability. As trehalose is a well known viability protectant in yeast cells against several adverse conditions, we determined its level. We measured the level of trehalose in cells submitted to heat shock, gamma irradiation and simulation of gastric environmental, all these conditions are commonly found during the bio therapeutic production and in the patients oral treatment. Trehalose levels were higher in yeast cells surviving to gamma irradiation ({sup 60} Cobalt) than in control cells. S. boulardii cells growth in log phase and submitted to the heat shock (40 deg C). Accumulated more trehalose than S. cerevisiae and unlikely to these cells, the pool of trehalose accumulated in S. boulardii was mobilized very slowly (70% of the trehalose pool was present 5 hours after the return to the normal temperature 30 deg C). Our results suggested a rather different trehalose metabolism in S. boulardii when compared with S. cerevisiae and showed that one of the response to the stress of irradiation was an increasing on the level of intracellular trehalose

  3. Influence of 60Co γ irradiation on fertility of Japanese pine sawyer beetle Monochamus alternatus hope (Coleoptera: Cerambycidae)

    International Nuclear Information System (INIS)

    The fertility of the Japanese pine sawyer beetle Monochamus alternatus (Coleoptera: Cerambycidae) irradiated with 60Co γ-rays was remarkable reduced at the doses of 30Gy, 35Gy and 40Gy, especially at 40Gy. When the non-irradiated females were coupled with the irradiated males first, and then coupled with non-irradiated males, the hatchability and the fertility had little higher but lower than the control. It explained that radiation has certain influence to the female gonad. It also has difference between the hatching rate and the amount of eggs in different match. (authors)

  4. Effect of gamma radiation (60Co) on the growth of Aspergillus ochraceus coffee (Coffea arabica L.)

    International Nuclear Information System (INIS)

    Coffee is a major product on the world market. Its acceptance depends strongly on the sensory characteristics of the beverage, that is its aroma and flavor. One of the most important aspects of coffee culture today is the cup quality as such all segments of coffee production network are concentrating efforts to improve this trait. Foods that have been contaminated with fungi may contain may produce many mycotoxins including ochratoxim A (OTA). To prevent OTA in foodstuffs, it is necessary detect the producing fungi early. Ionizing radiation is a safe, environmentally clean, energy efficient process that can be used to increase the quality and reducing the microbiological contamination of the coffee. The aim of the present study was to evaluate the effects of different gamma radiation doses (0.0, 6.0, 12.0 and 18.0 kGy) on the growth of Aspergillus ochraceus in coffee (Coffee arabica L.). The analysis were performed to determine the fungi contamination the results were expressed as the viable counts per gram of sample (CFU/g) coffee samples irradiated and unirradiated. The results shows that microbiological contamination of coffee disagrees when increase doses of irradiation. The radiation doses 6.0, 12.0 and 18.0 kGy used resulted in a elimination of the number of Aspergillus ochraceus CFU/g when compared to the nonirradiated control group. Under the present conditions, gamma radiation was found to be an alternative for the control of Aspergillus ochraceus. (author)

  5. Analysis of the frequency of unstable chromosome aberrations in human lymphocytes irradiated with {sup 60}Co; Analise da frequencia de alteracoes cromossomicas instaveis em linfocitos humanos irradiados com {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, Julyanne C.G.; Mendes, Mariana E.; Lima, Fabiana F., E-mail: july_cgm@hotmail.com, E-mail: mendes_sb@hotmail.com [Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Santos, Neide, E-mail: santos_neide@yahoo.com.br [Universidade Federal de Pernambuco (CCB/UFPE), Recife, PE (Brazil). Departamento de Genetica

    2013-07-01

    The aim of this study was to analyze the frequency of unstable chromosomal aberrations induced by gamma radiation from a {sup 60}Co source at two different doses. Samples were obtained from a healthy donor and exposed to {sup 60}Co source (Gammacel 220 ) located in the Department of Nuclear Energy of Pernambuco Federal University (DEN/UFPe/Brazil) with a rate of air Kerma to 3,277 Gy/h. Exposures resulted in absorbed dose 0.51 Gy and 0.77 Gy. Mitotic metaphases were obtained by culturing lymphocytes for chromosome analysis and the slides were stained with 5% Giemsa. Among the unstable chromosomal aberrations the dicentric chromosomes, ring chromosomes and acentric fragments were analyzed. To calculate the significance level the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. To calculate the significance level of the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. The results showed that there was significant difference of the frequencies of dicentric chromosomes (from 0.18 to 0.51 to 0.37 Gy to 0.77 Gy), however there was no statistically significant difference between the frequencies of acentric fragments ( 0.054 to 0, 51 Gy to 0.063 to 0.77 Gy) and ring chromosomes (0.001 to 0.51 Gy to 0.003 to 0.77 Gy). The low number of rings is found justified, considering that in irradiated human lymphocytes, its appearance is rare relative to dicentrics. The results confirm that dicentrics are the most reliable biomarkers in estimating dose after exposure to gamma radiation. These two points will make the calibration curve dose-response being built for Biological Dosimetry Laboratory of CRCN-NE/CNEN.

  6. Response of avocado genotypes to improvement through {sup 60}Co gamma radiation; Respuesta de diversos genotipos de aguacate al mejoramiento por radiacion gamma de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, E. De la; Rubi A, M.; Garcia A, J.M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    Ten avocado genotypes were subjected to gamma radiation from 0 to 45 Gy in 1993. Vegetative and reproductive data were analysed in a factorial design. Genotypes differed significative on height and fruit number. Radiation affected significative fruit number but not tree height. ''Hass'' showed strongest interaction between genotype and doses, for fruit number. (Author)

  7. Effects of 60Co gamma-rays, ultraviolet light, and mitomycin C on Halobacterium salinarium and Thiobacillus intermedius.

    Science.gov (United States)

    Shahmohammadi, H R; Asgarani, E; Terato, H; Ide, H; Yamamoto, O

    1997-03-01

    Lethal effects of 60Co gamma-rays, UV light, and mitomycin C on two kinds of bacteria, Halobacterium salinarium which grows in highly concentrated salt media and Thiobacillus intermedius which requires reduced sulfur compounds, were studied and compared with those on Escherichia coli B/r. D37 values for H. salinarium, T. intermedius and E. coli B/r were 393, 150, and 92 Gy, respectively, by exposure to 60Co gamma-rays. They were 212, 38, and 10 J/m2, respectively, by exposure to UV light and 2.36, 0.25, and 0.53 microgram/ml/h, respectively, by exposure to mitomycin C. Against these agents, H. salinarium was much more resistant than T. intermedius and E. coli B/r.

  8. Effects of {sup 60}Co gamma-rays, ultraviolet light, and mitomycin C on halobacterium salinarium and thiobacillus intermedius

    Energy Technology Data Exchange (ETDEWEB)

    Shahmohammadi, H.R.; Asgarani, E.; Terato, Hiroaki; Ide, Hiroshi; Yamamoto, Osamu [Hiroshima Univ. (Japan)

    1997-03-01

    Lethal effects of {sup 60}Co {gamma}-rays, UV light, and mitomycin C on two kinds of bacteria, Halobacterium salinarium which grows in highly concentrated salt media and Thiobacillus intermedius which requires reduced sulfur compounds, were studied and compared with those on Escherichia coli B/r. D{sub 37} values for H. salinarium, T. intermedius and E. coli B/r were 393, 150, and 92 Gy, respectively, by exposure to {sup 60}Co {gamma}-rays. They were 212, 38, and 10 J/m{sup 2}, respectively, by exposure to UV light and 2.36, 0.25, and 0.53 {mu}g/ml/h, respectively, by exposure to mitomycin C. Against these agents, H salinarium was much more resistant than T. intermedius and E. coli B/r. (author)

  9. Gamma irradiation effects in W films

    Energy Technology Data Exchange (ETDEWEB)

    Claro, Luiz H. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil) and Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei (Brazil); Santos, Ingrid A. [Instituto de Estudos Avancados - IEAv, Rod. dos Tamoios, km 5,5, CEP: 12228-840, Sao Jose dos Campos, SP (Brazil); Silva, Cassia F. [Faculdade de Tecnologia Sao Francisco - FATESF, Av. Siqueira Campos, 1174, CEP: 12207-000, Jacarei, SP (Brazil)

    2013-05-06

    Using the van Der Pauw methodology, the surface resistivity of irradiated tungsten films deposited on Silicon substrate was measured. The films were exposed to {gamma} radiation using a isotopic {sup 60}Co source in three irradiation stages attaining 40.35 kGy in total dose. The obtained results for superficial resistivity display a time annealing features and their values are proportional to the total dose.

  10. Radiosensibilidad de semillas de soya a los rayos gamma 60Co

    Directory of Open Access Journals (Sweden)

    C. de la Fé

    2000-01-01

    Full Text Available El presente estudio se desarrolló en las instalaciones del Instituto Nacional de Ciencias Agrícolas, con el objetivo de evaluar la radiosensibilidad de semillas de soya a los rayos gamma 60Co. Para su ejecución, se seleccionaron e irradiaron muestras de 50 semillas de la variedad Cubasoy-23, las que fueron sembradas en condiciones semicontroladas (macetas en la campaña de primavera, 1997. Las dosis de radiación fueron desde los 50 hasta los 480 Gy, con incrementos de 50 Gy entre las dosis de 50 y 200 Gy e incrementos de 40 Gy entre esta última y la dosis de 480 Gy. Las evaluaciones realizadas consistieron en porcentaje de semillas germinadas a los tres, seis y nueve días de la siembra, altura de las plantas a los 10, 20 y 50 días y número de pares de hojas emitidas a los 10 y 20 días de la siembra. El estudio realizado evidenció la ocurrencia de un efecto fuerte de las dosis aplicadas en el porcentaje de semillas germinadas, resultando las dosis próximas a los 280 Gy las de mayor efecto radioestimulador de la germinación. Desde el punto de vista de la altura de las plantas, el efecto de las dosis aplicadas se correspondió con el descrito para otros materiales biológicos irradiados, caracterizándose este por un aumento a dosis bajas seguido por una reducción cada vez mayor a medida que las dosis aplicadas se incrementaron. Por su parte, la emisión de hojas por las plantas mantuvo un comportamiento en correspondencia con la altura de las plantas. Los resultados del estudio permiten sugerir la aplicación de dosis próximas a los 360 Gy en los trabajos dirigidos a la creación de variabilidad genética en programas de mejora por inducción de mutaciones

  11. Effect of irradiation using 60Co on Trichinella spiralis larvae and on the eggs and protoscolices of Echinococcus granulosus

    International Nuclear Information System (INIS)

    The effect of irradiation using 60Co on Trichinella spiralis larvae and on the eggs and protoscolices of Echinococcus granulosus was studied. A dose of 30 Gy had no effect on T. spiralis larvae and on the eggs and protoscolices of E. granulosus. Irradiation of free T. spiralis larvae from muscle in normal saline exposed to 90 Gy and higher doses produced loss of infection in mice. There was reduction in the infectivity of eggs and protoscolices of E. granulosus by irradiation at a dose of 120 Gy, while there was complete loss of activity at a dose of 500 Gy. (author). 5 refs, 2 figs

  12. Effect of 60Co γ-rays irradiation pretreatment on callus inductivity and differentiation of strawberry anther

    International Nuclear Information System (INIS)

    Strawberry buds, in which a majority of pollen had single nuclear keeping to the side, were pretreated by 60Co γ-rays irradiation at different doses. The irradiation effect on the callus inductivity and plant differentiation rate of strawberry anther were studied. The results indicated that the pretreatment by 60Co γ-rays could increase the anther callus inductivity and plant differentiation rate significantly, and 20 Gy was the best dose. The callus inductivity of Akihime and Toyonoka increased by 39.09% and 35.68%, respectively, compared with the no-pretreatment materials. On the same media, the plant differentiation rate of Akihime and Toyonoka were also increased by 6.67%-6.72% and 4.73%-6.45%, respectively, compared with the two varieties of no-pretreatment. (authors)

  13. Manufacture of Single 60Co Source Irradiation Facility and the Measurement of Reference Radiation Filed

    Institute of Scientific and Technical Information of China (English)

    GAO; Fei; WANG; Hong-yu; NI; Ning; ZHANG; Li; HOU; Jin-bing; SONG; Ming-zhe

    2012-01-01

    <正>Reference radiation filed produced by isotope source is necessary for calibration of radiation dose meter. 60Co single source radiation facility is an important method to produce reference radiation. Collimation design of the facility is good for characteristics of the field, but there are scattered photon influences however. Scattered radiation is mainly come from collimation, source shield, floor, walls and

  14. Study on the down-regulation of PKCα by tamoxifen combined with 60Co γ-irradiation in glioma cells

    International Nuclear Information System (INIS)

    The mechanism of radio-sensitizing effect of tamoxifen on the influence of PKCα expression has been explored by tamoxifen combined with 60Co γ-irradiation in human glioma cells. The protein expression of PKCα and CyclinD1 were detected by using Western-Blot. The level of DNA strand breaks was detected by the alkaline single-cell gel electrophoresis assay. The results demonstrated that the combination of tamoxifen and 60Co γ-irradiation could reduce expression of PKCα and CyclinD1. And it also enhanced the radiation-induced DNA damage and attenuated the repair of damaged DNA. The above results reveal that the combination of tamoxifen and 60Co γ-irradiation can enhance the downregulation of the expression of PKCα and the induction in the low expression of CyclinD1 as well at the delay of DNA repair. All these may be related to the impairment of the radioresistance of SHG-44 cells by tamoxifen. (authors)

  15. Study on the energy dependence of gamma radiation detectors for {sup 137}Cs and {sup 60}Co; Estudo da dependencia energetica de detectores de radiacao gama para {sup 137}Cs e {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Nonato, Fernanda B.C.; Diniz, Raphael E.; Carvalho, Valdir S.; Vivolo, Vitor; Caldas, Linda V.E., E-mail: fbnonato@ipen.b, E-mail: rediniz@ipen.b, E-mail: vcsouza@ipen.b, E-mail: vivolo@ipen.b, E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    38 Geiger-Mueller radiation detectors and 9 ionization chambers were calibrated, viewing to study the energy dependence of the monitor response for gamma radiation fields ({sup 137}Cs and {sup 60}Co). The results were considered satisfactory only for ionization chambers and for some Geiger-Mueller detectors

  16. Effects of accumulated 60Co γ-ray irradiation on the small molecular metabolites in rats urine

    International Nuclear Information System (INIS)

    Objective: To explore the effects of accumulated 60Co γ-ray irradiation on small molecular metabolites in rats urine. Methods: Ten healthy male SD rats were irradiated by 60Co γ-rays in 5 days and the accumulated doses were 0, 0.2, 0.4, 0.6, 0.8, 1.0 Gy, respectively. The metabolites in urine of different groups were measured with 1H-NMR combined with principal components analysis (PCA) and partial least square discriminate analysis (PLS-DA). Results: The metabolites in rat urine were obviously changed after irradiation. Compared with control group, the amount of acetoacetate decreased after irradiation (t=29.7-30.7, P<0.05), but its relative level was stable when the dose increased (P>0.05). Meanwhile,the relative level of hippuric acid increased (t=4.4-21.6, P<0.05) especially when the accumulated dose was higher than 1 Gy (t=21.6, P<0.05). The relative level of proline, taurine and trimethylamine-N-oxide increased after irradiation with the same trend(t=3.5-13.4, 4.7-11.5, 2.9-12.7, P<0.05). Conclusions: The acetoacetate, hippuric acid, proline, taurine, and trimethylamine-N-oxide may be applicable for biomarkers of accumulative irradiation on rat. (authors)

  17. Resposta de sementes de amendoim a diferentes doses de radiação gama (60Co Response of peanut seeds to different levels of gamma radiation (60Co

    Directory of Open Access Journals (Sweden)

    Tatiana da S. Santos

    2010-10-01

    Full Text Available A radiação gama, proveniente da fonte de 60Co, é bastante utilizada para esterilização, visando a prevenção da decomposição e a toxidez de origem microbiana em diversos produtos. O grau de radiossensibilidade de um embrião vegetal depende da espécie, do estágio de seu desenvolvimento durante a radiação, da dose empregada e do critério usado para medir o efeito biológico, sendo comumente utilizado o teste de germinação. Objetivou-se, com este trabalho, estudar a sensibilidade do amendoim a radiação gama e seus efeitos na germinação, no vigor e na micoflora das sementes da cultivar BRS Havana, irradiadas com uma fonte de 60Co, tipo gammacell, com taxa de dosagem de 12,5 kGy h-1. As doses testadas em kGy foram as seguintes: 0; 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 6,0; 9,0; 12,0; 15,0; 18,0; 21,0 e 24,0. Com os resultados obtidos, concluiu-se que as doses acima de 3,0 kGy prejudicaram a viabilidade das sementes e as doses acima de 12 kGy comprometeram totalmente o vigor e a germinação das sementes de amendoim. A radiação a partir da dose 2,0 kGy eliminou os fungos Aspergillus flavus e Aspergillus niger e, a partir da dose 3,0 kGy, eliminou o Aspergillus glaucus. O Penicilium spp. permaneceu em mais de 30% das sementes em todos os tratamentos com radiação, não sendo eliminado até a dose de 24 kGy.The gamma radiation from 60Co source is widely used for sterilization aiming at preventing decomposition and toxicity from microbes in several products. The degree of radiosensitvity of a plant embryo depends on the species, the development stage during radiation, doses used and the criteria used to measure the biological effect, the germination test, being commonly used.This work aimed to study the peanut sensitivity to gamma radiation and its effects in the germination, in the vigour and seeds microflora of cultivar BRS Havana, irradiated with 60Co source, type gammacell with rate of dosage of 12.5 kGy h-1. The tested doses were the

  18. Effects of 60Co γ-ray irradiation on expression of surface antigens in endothelial cells of human umbilical veins

    International Nuclear Information System (INIS)

    Culture of endothelial cells of human umbilical veins and avidin-biotin peroxidase complex (ABC) immunochemical technique were used in the experiment to detect the surface antigens in endothelial cells. Endothelial cells separated from five umbilical cords in original culture were divided into two groups, irradiated and non-irradiated. The cells were irradiated with 15 Gy of 60Co γ-rays at dose rates of 21.78 cGy/min. Then antigens RBC A, HLA-ABC, HLA-DR, CD4 and CD8 were assayed for both groups by the method of ABC. The results showed that the values of integrated optical density (IOD) for the surface antigens in the irradiated cells were lower than those in the non-irradiated cells with the difference in antigen expression in endothelial cells being significant (P<0.05) between the two groups

  19. The protector role of Mn2+ in Saccharomyces cerevisiae exposed to 60Co gamma radiation

    International Nuclear Information System (INIS)

    The radiation is present on all over the world and can be classified, according to the effect that produces on matter, as non-ionizing and ionizing. The ionizing radiations transfer a sufficient amount of energy to the molecule and charged atoms called ions can be formatted. The biological organisms have approximately 70% of water and when submit to the incident radiation occur the radiolysis of water. Water radiolysis produces highly reactive oxygen species (ROS) known as free radicals. The ROS can interact with all important biomolecules like lipid, protein and DNA. This interaction can cause the loss of functions of theses molecules and thus lead to cell death. The manganese is a heavy metal that at low concentrations is essential for the biological system, since it is cofactor for action of several enzymes. At high concentrations the manganese is toxic to the organisms. Recently was observed that manganese can have a protector role against oxidative stress. In this work, it was studied the anti-oxidant role of manganese in cells submitted to gamma irradiation. It was performed the determination of two oxidative stress indicators: lipid peroxidation and determination of thiol group, the results presented suggest that the manganese had protective role against lipid damage and in this way, has an antioxidant role. (author)

  20. Immune response against the irradiated Bothropstoxin-1 with 60Co: identification of main cytokines involved and the participation of scavengers substances

    International Nuclear Information System (INIS)

    Considering the effects of gamma radiation on proteins and the ability of immune system to recognize modified macromolecules, we have identified the major cytokines involved in immune response of B10.PL, BALB/c and Knockout- IFNγ mice exposed to native or irradiated bothropstoxin-1 (BTHX-1), in the presence and absence of scavengers substances. In order to evaluate possible molecule structural modifications after being irradiated (60Co gamma rays), bothropstoxin-1 was submitted to SDS-PAGE analyses. Our results indicated that irradiation process has promoted modifications in the BTHX-1 molecule, however, in the presence of scavengers and even after irradiation process, the main band of toxin was preserved (14 kDa). Sera of animals immunized with the native or irradiated toxin, in the presence or not of scavengers, were analyzed in order to quantify specific isotopes. While the native BTHX-1 induced a predominant Th2 response, the irradiated toxin apparently promoted a switch towards a Th1 pattern. The toxin, when irradiated in the presence of t-butanol, induced to a lower production of IgG2b (Th1 response) if compared with the irradiated toxin without scavengers. We also performed a Real-time PCR to quantify the expression of cytokines IFN-γ, IL-2, IL-4 and IL-10 in spleen cells from mice. The cells of B10.PL and BALB/c mice immunized with native BTHX-1 and in vitro stimulated with irradiated toxin, showed higher expression of IFN-γ and IL-2 (Th1 response) than the control sample. The cells of Knockout-IFNγ mice immunized with native BTHX-1 showed higher expression of IL-4 (Th2 response). The cells obtained of B10.PL and BALB/c mice immunized with BTHX-1 + t-butanol, showed higher expression of IL-4 and IL-10, respectively. These facts reinforce the involvement of OH in the modulation of immune response against the irradiated toxin. (author)

  1. Influence of gamma ray irradiation on metakaolin based sodium geopolymer

    Energy Technology Data Exchange (ETDEWEB)

    Lambertin, D., E-mail: david.lambertin@cea.fr [CEA, DEN, DTCD/SPDE/LP2C, F-30207 Bagnols-sur-Cèze (France); Boher, C. [CEA, DEN, DTCD/SPDE/LP2C, F-30207 Bagnols-sur-Cèze (France); Dannoux-Papin, A. [CEA, DEN, DTCD/SPDE/LCFI, F-30207 Bagnols-sur-Cèze (France); Galliez, K.; Rooses, A.; Frizon, F. [CEA, DEN, DTCD/SPDE/LP2C, F-30207 Bagnols-sur-Cèze (France)

    2013-11-15

    Effects of gamma irradiation on metakaolin based Na-geopolymer have been investigated by external irradiation. The experiments were carried out in a gamma irradiator with {sup 60}Co sources up to 1000 kGy. Various Na-geopolymer with three H{sub 2}O/Na{sub 2}O ratios have been studied in terms of hydrogen radiolytic yield. The results show that hydrogen production increases linearly with water content. Gamma irradiation effects on Na-geopolymer microstructure have been investigated with porosity measurements and X-ray pair distribution function analysis. A change of pore size distribution and a structural relaxation have been found after gamma ray irradiation.

  2. Influence of gamma ray irradiation on metakaolin based sodium geopolymer

    Science.gov (United States)

    Lambertin, D.; Boher, C.; Dannoux-Papin, A.; Galliez, K.; Rooses, A.; Frizon, F.

    2013-11-01

    Effects of gamma irradiation on metakaolin based Na-geopolymer have been investigated by external irradiation. The experiments were carried out in a gamma irradiator with 60Co sources up to 1000 kGy. Various Na-geopolymer with three H2O/Na2O ratios have been studied in terms of hydrogen radiolytic yield. The results show that hydrogen production increases linearly with water content. Gamma irradiation effects on Na-geopolymer microstructure have been investigated with porosity measurements and X-ray pair distribution function analysis. A change of pore size distribution and a structural relaxation have been found after gamma ray irradiation.

  3. 60Co-irradiation as an alternate method for sterilization of penicillin G, neomycin, novobiocin, and dihydrostreptomycin

    International Nuclear Information System (INIS)

    The effects of the use of 60Co-irradiation to sterilize antibiotics were evaluated. The antibiotic powders were only occasionally contaminated with microorganisms. The D-values of the products and environmental isolates were 0.028, 0.027, 0.015, 0.046, 0.15, 0.018, and 0.19 Mrads for Aspergillus species (UC 7297, 7298), A. fumigatus (UC 7299), Rhodotorula species (UC 7300), Penicillium oxalicum (UC 7269), Pseudomonas maltophilia (UC 6855), and a biological indicator microorganism, Bacillus pumilus spores (ATCC 27142). An irradiation dose of 1.14 Mrads, therefore, was sufficient to achieve a six-log cycle destruction of B. pumilus spores. Based on the bioburden data, a minimum irradiation dose of 1.05 Mrads was calculated to be sufficient to obtain a 10(-6) probability of sterilizing the most radioresistant isolate, Pen. oxalicum. To determine the radiolytic degradation scheme and the stability of the antibiotics following irradiation, high-performance liquid chromatographic (HPLC) methods were developed. The resulting rates of degradation for the antibiotics were 0.6, 1.2, 2.3, and 0.95%/Mrad for penicillin G, neomycin, novobiocin, and dihydrostreptomycin, respectively. Furthermore, radiolytic degradation pathways for the antibiotics were identified and found to be similar to those commonly encountered when antibiotics are subjected to acidic, basic, hydrolytic, or oxidative treatments. No radiolytic compounds unique to 60Co-irradiation were found

  4. A prototype of an ionization chamber for gamma radiation beams of 60Co: Experimental and Monte Carlo preliminary results

    International Nuclear Information System (INIS)

    Ionization chambers are the most widely used instruments for dosimetry in radiotherapy. With the aim to test new configurations and materials using low-cost and easily-available components, verify the possibility of its application in the gamma radiation field of 60Co and fulfill the need of a chamber for scientific metrological purposes, in this paper the prototype of a plane-parallel ionization chamber has been designed and built, and its performance has been studied at the SSDL of KARAJ. The front wall and back wall of the chamber were made of graphite and Plexiglas respectively, as opposed to the one type of material in commercially available chambers. The collecting electrode has a diameter of 20 mm. The sensitive volume is 0.63 cm3. It was found that the Leakage current, the short-term stability and the polarity effect were within the international recommendations. The results were compared with those of a reference cylindrical chamber. The maximum difference observed in this comparison was 1.1%. The relative uncertainty was below 0.2%. Moreover, Monte Carlo simulation was undertaken using MCNP4C code and the relative difference of 1.9% was observed compared to the experiment. As a result the chamber presented a satisfactory performance in all evaluated tests in Gamma radiation field of 60Co. -- Highlights: • The prototype of a plane-parallel Ionization Chamber was designed. • Its performance was studied in Gamma radiation field of 60Co. • The response of the chamber was measured and compared with that of the cylindrical ionization chamber. • The chamber was simulated using the MCNP4C Monte Carlo code. • The Leakage current, the short-term stability and the polarity effect were within the international recommendations

  5. Suppression by ellagic acid of 60Co-irradiation-induced lipid peroxidation in placenta and fetus of rats

    International Nuclear Information System (INIS)

    The effect of ellagic acid, a component of Eucalyptus maculata, on lipid peroxidation was examined in placenta and fetus of pregnant rats irradiated with 60Co. The increase in lipid peroxide levels by the irradiation of the placenta and fetus brain as well as those of the serum and organs of mother was suppressed by treatment of the mother rats with ellagic acid. This suppressing effect found in placenta and fetus was significantly correlated with that found in mother rats. Moreover, ellagic acid suppressed the morphological changes such as degeneration in the endothelial cells of placenta and liver cells of fetus caused by the irradiation and improved the survival rate after the irradiation. These suppressing effects of ellagic acid were approximately the same as those of α-tocopherol. (author)

  6. The sensitivity of the most common microorganisms of pig liquid manure to the effect of 60Co irradiation

    International Nuclear Information System (INIS)

    In model experiments the most common representatives of pathogens and facultative pathogens of pig liquid manure contaminating bacterial flora were examined for their sensitivity to different doses of 60Co, using liquid medium supplemented with 1% glucose, as well as Korthof-medium and different kinds of selective media. Erysipelothrix rhusiopathiea, Brucella suis, Mycoplasma hyorhinis and Pasteurella haemolytica proved to be the most senstive ones to irradiation, as they did not survive 100 krad dose. The highest resistances were observed in the cases of the following microorganisms: the spore containing Bacillus anthracis, killed by 700 krad irradiation dose, the saprophytic and pathogenic Mycobacteria and the spore containing Clostridium perfringens, killed by 1000-1500 krad irradiation. (author)

  7. Effect of combination of STAT3 RNAi and 60Co γ-irradiation on U251 cell proliferation

    International Nuclear Information System (INIS)

    Objective: To construct signal transduction and activators of transcription 3 (STAT3) small interference RNA (siRNA) expression vector and to study its effect on STAT3 expression and U251 cell line proliferation. Methods: STAT3 specific 19 bp oligonucleotides were designed and synthesized. These oligonucleotides were annealed to form the double strand DNA fragments and these fragments were cloned into Psilence2.1-U6-H1 vector. The recombinant of STAT3-siRNA expressing construction was confirmed by Hind III and BamH I double digestion and sequencing. The STAT3-siRNA was transfected into U251 cell. The inhibitory effect of STAT3-siRNA construction was tested by Western blot. Cellular proliferation activities were measured by tetrazolium bromide (MTT) colorimetry. Cloning efficiency and MTF were used to confirm the radiation dose. Results: STAT3-siRNA expression vector was successfully constructed, and it could effectively down-regulate the protein levels of STAT3 in transfected U251 cell line; and the radiation dose was confirmed to 2 Gy. U251 cells transfected with STAT3-siRNA expression vector showed lower cellular proliferation compared with non-transfected U251 cells (P60Co γ-irradiation showed lower cellular proliferation compared with non-irradiated U251 cells (P60Co γ irradiation can enhance the inhibitory efficiency. (authors)

  8. Characterization of {sup 60}Co and {sup 137}Cs beams from irradiator Shepherd 81 - 14D of LNMRI/IRD in radiation protection; Caracterizacao dos feixes de {sup 60}Co and {sup 137}Cs do Irradiador Shepherd 81 - 14D do LNMRI/IRD em radioprotecao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, C.N.M. da; Cabral, T.S., E-mail: cosme@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The objective of this work is the characterization of {sup 60}Co beams and the {sup 137}Cs irradiator Shepherd 81-14D acquired by the National Metrology Laboratory of Ionising Radiation of the Institute of Radiation Protection and Dosimetry (LNMRI /IRD), for use in calibration of measuring instruments of gamma radiation in air kerma and ambient dose equivalent, irradiation of films and TLD's. Field homogeneity measurements were carried out, calculated input and output time of the source and commissioning of sources. (author)

  9. Effects of seed treatment with 60Co gamma rays and micronutrients on germination and growth of corn seedlings

    International Nuclear Information System (INIS)

    Gamma irradiation and soaking in solutions of some micronutrient elements, as presowing treatments of corn seeds, towards improving the germination of seeds, and increasing the growth of seedlings were investigated. The seeds were exposed to 12 irradiation doses of gamma rays ranging from 250-8000R. It was found that stimulatory effects on the germination percentage and capacity of seeds as well as the height and the dry weight of seedlings were exerted only by the low irradiation doses from 500-1000 R. Soaking cornseeds, before sowing, in any of the 4 concentrations ranging from 250-1000 ppm of molybdenum, manganese and zinc indicated that molybdenum treatment increased plant height the dry weight of seedlings; 500 ppm molybdenum gave the best effect. Irradiation of 500 ppm molybdenum soaked seeds with low doses of gamma rays stimulated the germination process and early growth of seedlings, with the 500 R dose being most effective. (author)

  10. Biological changes in Musca domestica L., 1758 (Diptera:Muscidae), induced by gamma radiation (60 Co)

    International Nuclear Information System (INIS)

    This work was carried out in the Entomology Section of the Centre of Nuclear Energy in Agriculture (CENA), University of Sao Paulo, Piracicaba, Sao Paulo, Brazil. The objective of the present research work was to investigate some effects of gamma radiation on the various stages of M. domestica life cycle. (author)

  11. Response of avocado genotypes to improvement through 60Co gamma radiation

    International Nuclear Information System (INIS)

    Ten avocado genotypes were subjected to gamma radiation from 0 to 45 Gy in 1993. Vegetative and reproductive data were analysed in a factorial design. Genotypes differed significative on height and fruit number. Radiation affected significative fruit number but not tree height. ''Hass'' showed strongest interaction between genotype and doses, for fruit number. (Author)

  12. 60Co-γ-irradiation of dried DNA and isolated cell nuclei of chicken erythrocytes

    International Nuclear Information System (INIS)

    In this work low molecular products, which resulted from γ-irradiation of dried DNA, were isolated and quantitatively determined. Unchanged nucleic bases were released. The irradiation was successful in a vacuum as well as in oxygen. In the case of the drily irradiated DNA, the base release made up 30% of the total strand breaks. The release of DNA bases was also first studied in cell nuclei of eucaryotic cells, the erythrocyte nuclei of chicken blood. The second part of this work dealt with the isolation and identification of radiation induced changes in the 2-dioxyribose unit of DNA. In the third part it was investigated, whether as a result of γ-irradiation of DNA malonic dialdehyde was formed. It could be shown that neither malonic aldehyde nor basic propenal were formed, but instead products, which were still bound to the DNA and formed a chromophore with 2-thio barbituric acid. In this work the direct irradiation effect was investigated in DNA systems as well as in erythrocyte nuclei. By the isolation of low molecular irradiation products this work offers a contribution to the understanding of the irradiation chemistry in an eucaryotic cell, in which the direct effect on the DNA and the resulting radiation damage were given a deciding role for genetic information. (orig./MG)

  13. Effect of 60Coirradiation on mating ability of males of Helicoverpa armigera

    International Nuclear Information System (INIS)

    The effects of γ-rays irradiation on the mating ability and flight capability of male cotton bollworm Helicoverpa armigera were studied in laboratory and field cages. The results showed that when the irradiation dose increased from 0Gy to 400Gy, the flight capability decreased: flight distance decreased from 69.65km to 38.30km; average flight distance decreased from 44.19km to 13.55km. The longevity of the irradiated males was significantly shorter than that of the wilds but there was no significant difference according to different doses. Egg hatchability was affected significantly by irradiation but there was no significant difference in eggs laid per female, fecundation eggs as increasing treated doses. When the ratio of sterilized males (treated dose 200 Gy) to fertile males was as 5:1 in field cages, the F1 hatchability was significantly decreased and the purpose of controlling cotton bollworm population could be effectively achieved. (authors)

  14. An investigation on the radiation sensitivity of DNA conformations to 60Co gamma rays by using Geant4 toolkit

    International Nuclear Information System (INIS)

    To investigate the impact of conformational properties of genetic material of living cells on radiation-induced DNA damage, single strand breaks (SSB), double strand breaks (DSB) and some microdosimetric quantities of A, B and Z-DNA conformations caused by 60Co gamma rays, have been calculated. Based on a previous B-DNA geometrical model, models of A and Z forms have been developed. Simple 34 base pairs segments of each model repeated in high number and secondary electron spectrum of 60Co gamma rays have been simulated in a volume of a typical animal cell nucleus. All simulations in this study have been performed by using the Geant4 (GEometry ANd Tracking 4)-DNA extension of the Geant4 toolkit. The results showed that, B-DNA has the lowest yield of simple strand breaks with 2.23 × 10−10 Gy−1 Da−1 and 1.0 × 10−11 Gy−1 Da−1 for the SSB and DSB damage yield, respectively. The A-DNA has the highest SSB yield with 3.59 × 10−10 Gy−1 Da−1 and the Z-DNA has the highest DSB yields with 1.8 × 10−11 Gy−1 Da−1. It has been concluded that there is a direct correlation between the hit probability, mean specific imparted energy and SSB yield in each model of DNA. Moreover, there is a direct correlation between the DSB yield and both the mean lineal energy and topological characteristics of each model

  15. An investigation on the radiation sensitivity of DNA conformations to {sup 60}Co gamma rays by using Geant4 toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Semsarha, F. [Institute of Biochemistry and Biophysics (IBB), University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Goliaei, B., E-mail: goliaei@ibb.ut.ac.ir [Institute of Biochemistry and Biophysics (IBB), University of Tehran, P.O. Box 13145-1384, Tehran (Iran, Islamic Republic of); Raisali, G.; Khalafi, H. [Radiation Applications Research School, Nuclear Science and Technology Research Institute, P.O. Box 11365-3486, Tehran (Iran, Islamic Republic of); Mirzakhanian, L. [Medical Physics Unit, McGill University, 1650 Cedar Avenue, Montreal, Quebec (Canada)

    2014-03-15

    To investigate the impact of conformational properties of genetic material of living cells on radiation-induced DNA damage, single strand breaks (SSB), double strand breaks (DSB) and some microdosimetric quantities of A, B and Z-DNA conformations caused by {sup 60}Co gamma rays, have been calculated. Based on a previous B-DNA geometrical model, models of A and Z forms have been developed. Simple 34 base pairs segments of each model repeated in high number and secondary electron spectrum of {sup 60}Co gamma rays have been simulated in a volume of a typical animal cell nucleus. All simulations in this study have been performed by using the Geant4 (GEometry ANd Tracking 4)-DNA extension of the Geant4 toolkit. The results showed that, B-DNA has the lowest yield of simple strand breaks with 2.23 × 10{sup −10} Gy{sup −1} Da{sup −1} and 1.0 × 10{sup −11} Gy{sup −1} Da{sup −1} for the SSB and DSB damage yield, respectively. The A-DNA has the highest SSB yield with 3.59 × 10{sup −10} Gy{sup −1} Da{sup −1} and the Z-DNA has the highest DSB yields with 1.8 × 10{sup −11} Gy{sup −1} Da{sup −1}. It has been concluded that there is a direct correlation between the hit probability, mean specific imparted energy and SSB yield in each model of DNA. Moreover, there is a direct correlation between the DSB yield and both the mean lineal energy and topological characteristics of each model.

  16. Induction of mutation in Jujube (Zizyphus jujuba Mill) using tissue culture combined with 60Coγ-ray irradiation

    International Nuclear Information System (INIS)

    In vivo and in vitro mutagenesis techniques were assayed to explore effects of irradiation in jujube (Ziziphus jujuba Mill) improvement. 60Co γ-ray irradiated seeds and shoot tips of a land race of jujube originating in Shangdong province of China were micropropagated up to M1V4 generation on MS basal medium containing 2 mg/L BA and 0.4 mg/L IBA. The rooting MS medium contained 1 mg/L BA and 0.6 mg/L IAA, ZEA 1 mg/L, 2, 4-D 0.5 mg/L, and NAA 0.5 mg/L in different combinations. Adventitious buds were also produced from irradiated calli derived from leaf and hypocotyl fragments and the elongated adventitious buds rooted in vitro prior to green house transfer. Different doses (20 to 900Gy) were tested for in vitro explants as well as the jujube kernels irradiation. Six types of leaf shape and seven types of fruit shape mutations were observed and different ripening characters and growth habits were recorded in the orchard on putatively mutated mature trees. Even though there is a need for confirmation and molecular characterization, these mutations may be considered as a new and powerful way for jujube improvement in order to develop genotypes with promising value added traits. (author)

  17. Double strand breaks in DNA in vivo and in vitro after 60Co-γ-irradiation

    International Nuclear Information System (INIS)

    The questions of what the correlation is between double strand breaks in DNA in the cell and lethal radiation damage and by means of which possible mechanisms DNA double strand breaks could occur were studied. E. coli served as test system. In addition to this the molecular weight of the DNA from irradiated E. coli as a function of the radiation dose under various conditions was measured. This data was compared on the one hand to the survival of the cell and on the other hand to the formation of DNA double strand breaks in an aqueous buffer system, which in its ionic characteristics was similar to cell fluids. (orig./MG)

  18. Displacement correction factor versus effective point of measurement in depth dose curve measurements at 60Co gamma rays

    International Nuclear Information System (INIS)

    The discrepancies in data sets of values of the Displacement Factor pd recommended by different codes of practices for calibration purpose still demand further investigation to clarify this point. In this paper, we propose an experimental method to determine the displacement factor for cylindrical ionization chambers (thimble chambers) in photon beams. Measurements of pd for several depths were performed for 60Co gamma rays. From these results we calculated the shift of the effective point of measurement (z-zeff) for different depths. The results obtained in this work shown: (a) there is no significant change in pd from 2 cm to 17 cm of depth in water; (b) the value of pd for a ion-chamber Farmer type (inner radius r = 3.15 cm) is pd 0.988; (c) the shift of the effective point of measurement has a smooth variation with depth; (d) the value of (z-zeff) at the recommended calibration depth for 60Co beams (5 cm) is 0.6r (with r: inner radius of the chamber). The result (b) confirms the value of pd suggested by the SEFM and NACP protocols and differs with that of the AAPM. The value obtained for (z - zeff) (d) is very closed to that recommended by the IAEA TRS-277. Finally, the results (a) and (c) suggest that it should be preferable to use the displacement factor instead of effective point of measurement to perform measurements of depth dose curves, since the use of zeff should take into account its dependence on depth. (author). 7 refs, 4 figs

  19. DNA double-strand break and apoptosis induction in human lymphocytes in different cycle cell phases by 60Co gamma rays and Bragg peak protons of a medical beam

    International Nuclear Information System (INIS)

    A comparative analysis is made of the regularities in the formation of DNA double-strand break and apoptosis induction in peripheral human blood lymphocytes in different cell cycle phases after 60Co gamma and extended Bragg peak proton irradiation. It is shown that the formation of apoptotic cells in a lymphocyte population increases linearly in all the cell cycle stages after proton irradiation. The maximal DNA double-strand break and apoptosis yield in lymphocytes is observed in the S phase of the cell cycle

  20. High dose rate /sup 60/Co remote afterloading irradiation in cancer of the cervix in Haiti, 1977-1984

    Energy Technology Data Exchange (ETDEWEB)

    Streeter, O.E. Jr.; Goldson, A.L.; Chevallier, C.; Nibhanupudy, J.R.

    1988-06-01

    From 1977 through 1984, 293 previously untreated patients with biopsy proven carcinoma of the uterine cervix were treated by whole pelvis irradiation and high intensity 60Co remote afterloading (RAL) intrauterine tandem techniques in Haiti. The treatment results were analyzed retrospectively to evaluate the therapeutic results and prognostic factors of a strict protocol involving 40 Gy to the whole pelvis (2 Gy/day, 5 days/week). In addition, on the 5th day of the 3rd week, the first outpatient 60Co remote afterloading intracavitary insertion, delivering 7.5 Gy to point A with each insertion, repeated 3 times by a week separation for a total of 4 times. The total TDF for external beam plus RAL was 158 and 175 for early and late effects respectively. One hundred-four patients were evaluable after 1 year or more follow-up, with a median of 26.5 months. No evidence of disease (NED) by Stage at 1 year was: Stage I of 100% (3/3), Stage II of 82% (9/11), Stage III of 80% (47/59), and Stage IV of 58% (18/31). The post-therapeutic complication rate was 7.7%, with no fistulas or requirement of surgical intervention. Those with documented follow-up of at least 2 years (74 patients) had comparable survival to other high dose rate and low dose rate studies. This study shows that outpatient brachytherapy can be carried out without sophisticated and expensive equipment with minimal staff trained in radiation therapy. A detailed description of this outpatient RAL technique and results are described so that this method can be adapted to other developing and industrialized nations where cost containment is becoming a key issue.

  1. Influence of natural antioxidants on lipid composition of beef burgers submitted to irradiation in 60 Co source and electron beams

    International Nuclear Information System (INIS)

    Radiation processing has been employed in some countries as a mean of treatment to assure microbiological safety of meat and meat products, avoiding the occurrence of food-borne disease. The ionizing radiation may cause some undesirable changes on chemistry composition of food and the lipid oxidation is one of the main reactions. In meat products processing industry, the lipid composition is directly related to nutritional and sensory quality of the product. For preventing oxidation, use of antioxidants which can be synthetic or natural, has been practically applied in some products. Currently, most attention has been given to natural antioxidants from herbs and spices like rosemary and oregano. The aim this study was to assess the antioxidant effects of either rosemary and oregano extract in beef burgers submitted to irradiation in 60Co source with dose 6, 7 e 8 kGy, electron beams with dose 3,5 e 7 kGy and storage under freeze along 0, 45 e 90 days. The results showed that rosemary extract has the major antioxidant effects when it is used on heterogeneous food matrix like beef burger, but oregano extract was better efficient to delay lipid oxidation along storage time when it is used in synergism with rosemary and/or BHT/BHA. Although to have occurred changes in the fatty acids composition it was not possible to demonstrate a straight dependence of irradiation dose and/or storage time. Sensory analysis showed that between the samples prepared with natural antioxidants, the beef burger prepared with oregano has received better scores by panelists. Irradiated beef burger prepared with rosemary has received better scores when compared to non-irradiated one. The use of spices with antioxidant activity to avoid the oxidative damage in foods that contain fats in their formulation is thought to be promising to application in food facilities. (author)

  2. Microbial determination of Cumin by gamma irradiation

    International Nuclear Information System (INIS)

    Cumin is one of the valuable export items of Iran, and like most of the agricultural products it is contaminated by microorganisms. Due to importance of this product, the gamma irradiation method, which has applications in microbial decontamination, has been used for the improving its quality and increasing the shelf life-time. For this purpose pak ages of 10 gr of cumin were irradiated by 2,4,6 and 8 KGy from 60Co source. With each dose, four samples were irradiated and results were compared with controlled not irradiated samples. According to the standard limitation of bacteria and molds the total optimum doses are 7.5 and 5 KGy respectively

  3. Brain anomalies induced by gamma irradiation in prenatal period

    International Nuclear Information System (INIS)

    Gamma irradiation has been utilized in order to produce cortical and callosal abnormalities. We have also checked for the presence of the aberrant longitudinal bundle in the brains of mice born acallosal due to prenatal irradiation is also checked. Pregnant mice were exposed to gamma irradiation from a 60 Co source at 16, 17 and 19 days of gestational age (E 16, E 17 and E 19) with total doses of 2 Gy and 3 Gy. At 60 days postnatal the offspring of irradiated animals were intra cardiac perfused, the brains were removed from the cranio and cut into coronal or para sagittal sections. (author)

  4. Effect of low dose irradiation of 60Co γ-rays on seed germination, seedling growth and enzymes activity of Lactuca sativa

    International Nuclear Information System (INIS)

    The seeds of Lactuca sativa were irradiated by different doses (10, 20, 30, 40, 50 Gy) of 60Co γ-rays. The effects of low dose irradiation on seed germination, seedling growth and enzymes activity were investigated. The results indicated that low dose irradiation could promote germination rate, germinating viability, germination rate in the field, root length and height of seedling. The suitable dosage for low dose irradiation for Lactuca sativa was 30 Gy. POD activity after irradiation treatment in the range of 10 to 50 Gy and CAT activity after irradiation treatment in the range of 20 Gy to 40 Gy was lower than that of control. (authors)

  5. Effect of 60Co-gamma radiation on the random walk error of interferometric fiber optic gyroscopes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Two 60Co-gamma radiation experiments were launched to explore the radiation effect on optical components and interferometric fiber optic gyroscope (IFOG). In optical components radiation experiment, the result showed that polarization-maintaining (PM) fiber coil loss was the most affected parameter in all the RWC (random walk coefficient) related parameters, compared with the weak sensitivity of other components parameters. In the IFOG radiation experiment, the RWC performance degradation was found to be almost due to an increase of the PM fiber attenuation. Based on the experiment result, a RWC prediction model in radiation, which is obtained by embedding PM fiber loss expression into the RWC model, was built following a power law of dose and dose rate. An IFOG RWC in space radiation environment was predicted from radiation dose and dose rate by the RWC prediction model. This RWC value calculated from test data is fully accorded to the RWC value predicted from radiation dose.

  6. Production of ochratoxin a by aspergillus ochraceus NRRL-3174 before and after exposures to /sup 60/Co irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Applegate, K.L.; Chipley, J.R.

    1976-03-01

    Spores from the toxigenic organism Aspergillus ochraceus NRRL-3174 were exposed to specific levels of gamma irradiation and then allowed to germinate on selected media. Increases in ochratoxin A production by irradiated, compared to non-irradiated, spores were observed after inoculation of spores onto a cracked red wheat or into a synthetic liquid medium. Variations in daily ochratoxin production were also observed for control and irradiated spore-derived cultures developing on both media, with maximum toxin production varying from 7 to 11 days of incubation. The most notable increases in ochratoxin A production occurred from cultures developing from spores having been irradiated with 10, 25, or 50 krad. Exposures to 400 or 600 krad resulted in complete inhibition of spore germination and, consequently, no ochratoxin production. Of the two substrates used, wheat and synthetic, the quantities of ochratoxin A produced were significantly lower in the synthetic media than on the natural substrate. Higher and more rapid toxin production occurred from spores having been irradiated with 10, 25, 50, and 100 krad than occurred from the non-irradiated control spores when grown on synthetic media. Cultures derived from spores having been exposed to 10, 25, and 50 krad produced significantly higher levels of ochratoxin A after 8 days of incubation on natural substrate than did the controls. Analysis of variance revealed that substrate, length of incubation, as well as irradiation levels all affected the time required to produce maximum levels of ochratoxin A.

  7. 60Coγ射线损伤后小鼠造血系统生理指标的动态变化%Changes of Physiological Indexes in Hematopoietic System of Mice after 60Coγ Ray Irradiation

    Institute of Scientific and Technical Information of China (English)

    侯新然; 王晓波; 袭荣刚; 李忠亮; 高慧媛; 吴立军; 马晓梅

    2012-01-01

    Objective To explore the physiological variation of the hematopoietic system in mice after C07 ray irradiation. Methods Body weight, peripheral blood cell counts,the immune organ index and pathological changes in femoral bone marrow of mice were measured at different times after whole-body irradiation with C07 ray. The doses were 2,4,6 Gy respectively. Results The changes of peripheral blood of mice were different. The white blood cell counts declined most rapidly and obviously,followed by the platelet count,with a dose-effect relationship. Three days after radiation, the immune organ index of mice decreased significantly compared with the immune organ index in mice unirradiated. Myeloid elements in bone marrow were reduced and bone marrow hematopoiesis was depressed. Body weight of irradiated mice grew slowly, without significant difference with mice unirradiated. Conclusion 60Coγ ray radiation can decrease peripheral blood cells, decrease the immune organ index and inhibit bone marrow cell proliferation in mice.%目的 探索小鼠60Coγ射线损伤后造血系统各项生理指标的变化规律.方法 采用60Coγ射线对小鼠进行一次性全身照射,剂量分别为2、4、6 Gy,在不同时间分别测定小鼠体质量,外周血细胞计数,免疫器官指数及股骨骨髓的病理变化.结果 照射后小鼠的外周血象有变化,其中白细胞下降最迅速且明显,其次是血小板,且具有剂量效应关系.照射后3d免疫器官指数下降明显,与对照组比较具有显著性差异;骨髓造血细胞数目迅速减少,出现造血抑制;照射后小鼠体质量增加缓慢,但与对照组比较无显著性差异.结论 60Coγ射线照射可引起小鼠外周血细胞下降,免疫器官指数下降,并抑制骨髓造血细胞增生.

  8. Effects of 60Co gamma radiation on toxicity and hemorrhagic, myonecrotic, and edema-forming activities of Cerastes cerastes venom

    International Nuclear Information System (INIS)

    Antisera are used as effective antidotes against the local effects of snake bites. To improve antisera production and extend the life of surrogates used to produce antibodies, the chronic effects of venom toxicity must be reduced. The present study evaluated the effectiveness of gamma irradiation to reduce the local effects associated with viperid snake bites by evaluating in NMRI mice the toxicity and edematic, hemorrhagic, and myonecrotic activities of native and irradiated Cerastes cerastes venoms. These results indicated that the toxicity of irradiated venoms (1 and 2 kGy) decreased as compared with that of native venom. The edematic and hemorrhagic activities were also reduced in the detoxified samples, particularly with the 2-kGy radiation dose. Furthermore, the creatine phosphokinase (CPK) activity was significantly increased in the serum and decreased in the myocardium after envenomation with native venom, but no significant enzymatic changes were observed in mice envenomated with irradiated venom. Histopathologic evaluation showed that native venom caused severe degenerative changes in the myocardium. In the case of 2-kGy-irradiated venom, no tissue alterations were observed. These results indicate that irradiation of venom with a 2-kGy dose may offer an effective method for reducing the chronic toxic effects of venom in immunized animals. (author)

  9. Study of the action of 60Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp

    International Nuclear Information System (INIS)

    The application of non-thermal treatments has proven effective in inhibiting bacteria such as Salmonella and Escherichia coli. Mango is a fruit of national consumption with a great exportation potential. Meanwhile, outbreaks of food borne disease related to mango consumption caused mistrust on the degree of food security offered by the product. The objective of this work was to establish the radioresistance of bacteria Escherichia coli, Salmonella Poona and Alicyclobacillus acidoterrestris on the mango pulp by the calculation of the D10 values and to know the radiation effect on the sensory characteristics of the fruit pulp. The microbiological profile of frozen mango pulp available at the local market was also established using conventional methods of plating and Most Probable Number (MPN). The pulps experimentally inoculated with the bacteria listed above were irradiated with doses of 0, 1, 2, 3, 4 and 5kGy in a 60Co source. The sensory analysis was performed using a dose of 5 kGy, using the triangular test and the test of acceptance with hedonic scale. The results of this study show that the quality of mango pulp sell in the local market is not satisfactory in accordance with the standards established by the Brazilian law and the literature, showing the need of using other tools to achieve acceptable levels of quality. The D10 values obtained are in the range of 1.01 and 1.09kGy for E. coli ATCC 8739, 0.60 and 0.98kGy for S. poona and 0.72 e 0.88kGy for A. acidoterrestris respectively. The triangular test showed that a 5kGy radiation dose changed the sensory characteristics of mango pulp. Nevertheless, sensory analysis of a food product prepared with the irradiated pulp obtained good acceptance in the attributes of global appearance, flavor and aroma. (author)

  10. Study of the action of 60Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp

    International Nuclear Information System (INIS)

    The application of non-thermal treatments has proven effective in inhibiting bacteria such as Salmonella and Escherichia coli. Mango is a fruit of national consumption with a great exportation potential. Meanwhile, outbreaks of foodborne disease related to mango consumption caused mistrust on the degree of food security offered by the product. The objective of this work was to establish the radioresistance of bacteria Escherichia coli, Salmonella Poona and Alicyclobacillus acidoterrestris on the mango pulp by the calculation of the D10 values and to know the radiation effect on the sensory characteristics of the fruit pulp. The microbiological profile of frozen mango pulp available at the local market was also established using conventional methods of plating and Most Probable Number (MPN). The pulps experimentally inoculated with the bacteria listed above were irradiated with doses of 0, 1, 2, 3, 4 and 5 kGy in a 60Co source. The sensory analysis was performed using a dose of 5 kGy, using the triangular test and the test of acceptance with hedonic scale. The results of this study show that the quality of mango pulp sell in the local market is not satisfactory in accordance with the standards established by the Brazilian law and the literature, showing the need of using other tools to achieve acceptable levels of quality. The D10 values obtained are in the range of 1.01 and 1.09 kGy for E. coli ATCC 8739, 0.60 and 0.98 kGy for S. poona and 0.72 and 0.88 kGy for A. acidoterrestris respectively. The triangular test showed that a 5 kGy radiation dose changed the sensory characteristics of mango pulp. Nevertheless, sensory analysis of a food product prepared with the irradiated pulp obtained good acceptance in the attributes of global appearance, flavor and aroma. (author)

  11. Differential expression profiles of microRNAs in liver of 60Co γ-ray irradiated mice

    International Nuclear Information System (INIS)

    Objective: To investigate the differential expression profiles of microRNAs in the liver of 60Co γ-ray irradiated mice using microRNA microarray and to explore their main functions by bioinformatic analysis. Methods: After SPF C57BL/6J mice expose to 4 Gy-single whole body radiation,total number of peripheral WBC and the fMNPCE were measured at 3 d.The differentially expressed miRNAs in mouse liver were detected with miRNA microarray, miRNA-124 and miR-34a were confirmed by real time RT-PCR assay. Bioinformatic analysis was applied to explore target genes and the main functions of the differential expressed miRNAs. Results: Compared with control group, the total number of peripheral WBC decreased (t=2.87, P<0.05), while the fMNPCE in bone marrow increased (t=-2.91, P<0.05) after 4 Gy γ-ray irradiation.miRNA microarray revealed that 17 miRNAs were differentially expressed, in which 9 up-regulated, 8 down-regulated. The expression levels of miR-124 and miR-34a were coincident with the result of real time RT-PCR. GO analysis showed that some pathways including adherens junction and cell cycle were suppressed, while some immune-related pathways were activated. Conclusions: miR-34a and miR-194 were involved in the regulation of acute radiation damage, some other miRNAs including miR-124, miR-382 and miR-92a* also played important roles in radiation process. (authors)

  12. Sterilization by gamma irradiation

    International Nuclear Information System (INIS)

    Since 1980 the National Institute of Nuclear Research counts with an Industrial Gamma Irradiator, for the sterilization of raw materials and finished products. Through several means has been promoted the use of this technology as alternative to conventional methods of sterilization as well as steam treatment and ethylene oxide. As a result of the made promotion this irradiator has come to its saturation limit being the sterilization irradiation one of the main services that National Institute of Nuclear Research offers to producer enterprises of disposable materials of medical use also of raw materials for the elaboration of cosmetic products and pharmaceuticals as well as dehydrated foods. It is presented the trend to the sterilization service by irradiation showed by the compilation data in a survey made by potential customers. (Author)

  13. Study of recombination processes for 'electron-hole' pairs in germanium irradiated by {gamma} rays from {sup 60}Co using the photovoltaic effect in P-N junctions; Etude du processus de recombinaison des paires ''electron-trou'' dans le germanium irradie par les rayons {gamma} du cobalt 60 a l'aide de l'effet photovoltaique dans les jonctions P-N

    Energy Technology Data Exchange (ETDEWEB)

    Zahedi-Mochadam, A.A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-10-01

    Using the photo-voltaic effect in p-n junctions, we have studied, during bombardment, the mechanism of the recombination of 'electron-hole' pairs in the presence of structure defects produced in germanium of the N and P types by {gamma} rays from a Co{sup 60} source. At 310 K the level of the recombination centres is situated 0.25 eV above the conduction band and the capture cross-sections of the holes and of the electrons have the respective values of: {sigma}{sub p} = 4 X 10{sup -15} cm{sup 2} and {sigma}{sub n} = 3 X 10{sup -15} cm{sup 2}. The value of {sigma}{sub n} appears to be under-estimated because the number of defects in P-type samples appears to be lower than that in N-type samples. These results lead to the conclusion that the interstitials are responsible for the recombination. At 80 K it has been found that in N-type samples, a shallow level exists at O.05 eV below the conduction band with a capture cross-section for the holes of {sigma}{sub p} {>=} 10{sup -14} cm{sup 2}. We believe that in this case the recombination of charge carriers is controlled by the neighbouring 'defect-interstitial' pairs. In P-type samples at low temperature, the life-time is practically constant during irradiation. This fact is attributed to a spontaneous annealing of defects ol purely electrical origin. In the last part of the work the study of the photo-voltaic effect applied to the problem of gamma radiation dosimetry is considered. It is shown that such dosimeters, based on this principle, make it possible to measure the intensity of gamma rays over a very wide range. (author) [French] En utilisant l'effet photovoltaique dans les jonctions p-n, nous avons etudie au cours du bombardement le mecanisme de recombinaison des paires 'electron-trou' en presence des defauts de structure introduits dans le germanium de type N et de type P par les rayons gamma d'une source de Co{sup 60}. A 310 K, le niveau des centres de recombinaison se

  14. The effects of seeds irradiation with 60Co γ-ray on seed germination and shoot growth of Brassica campetris L. ssp. Chinensis var. utilis

    International Nuclear Information System (INIS)

    Seeds of Brassica campetris L. ssp. Chinensis var. utilis pre-soaked with water for 1h were irradiated with 60Co γ-ray. Irradiation delayed the germination of seeds but did not affect the germination rate. The height, root length, fresh weight and survival rate of seedlings decreased with the increasing of irradiation dose. There were significant negative correlation between death rate and the height, root length and fresh weight. The dose of 200 - 300 Gy were recommended as suitable irradiation doses for pre-soaked seeds

  15. 60Co-γ辐射对菊苣种子发芽及幼苗生理的影响%Effects of 60Co-γ-rays Irradiation on Chicory Seed Germination and Seedling Physiology

    Institute of Scientific and Technical Information of China (English)

    张玉; 白史且; 李达旭; 王曾珍

    2013-01-01

    Chicory seeds were irradiated with 60Co-γ-rays at 100, 150, 200 and 300 Gy to determine germination rate and physiological characteristics from mutagenic effects of irradiation doses. Results showed that seed germination rate decreased as the irradiation dosage increased. There was significant difference between 200 Gy irradiation dosage and control(P<0. 05). Superoxide dismutase (SOD) activities, peroxi-dase (POD) activities, soluble protein and soluble sugar contents first increased then declined with a gradual irradiation increase, and differed significantly between control and 150 Gy, 100 Gy, 150 Gy, 150 Gy treatments (P<0. 05), respectively. MDA content increased with increased irradiation dosage, and there was significant difference between control and the treatments above 150 Gy dose (P<0. 05). The protein content first increased then declined, and differed significantly between control and treatments (P<0. 05). It was concluded that the mutagenic effect of chicory irradiated by low dosage (below 150 Gy) was not obvious. However, physiological and biochemical characteristics of chicory irradiated above 200 Gy were significantly altered. The study provides a theoretical basis for chicory radiation mutation breeding.%为明确60 Co-γ射线对菊苣(Cichorium intybus L.)辐照诱变效果,采用不同剂量60Co-γ射线(100 Gy,150 Gy,200 Gy和300 Gy)辐照处理菊苣种子,测定其发芽率和相关生理指标.结果表明:随着辐照剂量的增加,菊苣发芽率降低,200 Gy以上辐照处理发芽率与对照差异显著(P<0.05);超氧化物歧化酶(SOD)、过氧化物酶(POD)活性、可溶性蛋白和可溶性糖含量随着辐照剂量增加均表现为先升后降的趋势,分别在辐射剂量为150 Gy,100 Gy,150Gy,150 Gy及以上时与对照差异显著(P<0.05);丙二醛(MDA)含量随着辐照剂量增加而逐渐升高,150 Gy以上辐照处理与对照差异显著(P<0.05);蛋白含量呈现先增后减的趋

  16. The effects of 60Co γ-ray irradiation on the DC characteristics of enhancement-mode AlGaN/GaN high-electron-mobility transistors

    Institute of Scientific and Technical Information of China (English)

    Chen Chao; Tian Ben-Lang; Liu Xing-Zhao; Dai Li-Ping; Deng Xin-Wu; Chen Yuan-Fu

    2012-01-01

    The effects of 60Co y-ray irradiation on the DC characteristics of AlGaN/GaN enhancement-mode high-electronmobility transistors (E-mode HEMTs) are investigated.The results show that having been irradiated by 60Coγ-rays at a dose of 3 Mrad (Si),the E-mode HEMT reduces its saturation drain current and maximal transconductance by 6% and 5%,respectively,and significantly increases both forward and reverse gate currents,while its threshold voltage is affected only slightly.The obvious performance degradation of E-mode AlGaN/GaN HEMTs is consistent with the creation of electronegative surface state charges in the source-gate spacer and gate-drain spacer after being irradiated.

  17. The effect of combination of ErbB2 RNAi and 60Co γ-irradiation on U251 cell apoptosis

    International Nuclear Information System (INIS)

    To construct erythroblastic leukemia viral oncogene homolog 2 (ErbB2) small interference RNA (siRNA) expression vector and to study its effect on U251 cell line proliferation and apoptosis combining with 60Co γ-irradiation. ErbB2 specific 19bp oligonucleotides were designed and synthesized. These oligonucleotides were annealed to form the double strand DNA fragments, which was cloned into pSilence2.1-U6-H1 vector. The recombinant pSilence2.1-ErbB2 expression construct was confirmed by Hind III and BamH I double digestion and sequencing. The pSilence 2.1-ErbB2 was transfected into U251 cell. Cellular proliferation activities were assayed by tetrazolium bromide (MTT) colorimetry. The apoptosis of transfected U251 cell was examined with Hoechst 33258 staining and Annexin-V kit. Psilence 2.1-ErbB2 expression vector was successfully constructed and it can effectively inhibit pro- liferation(p60Co γ-irradiation, the effect of inhibiting proliferation was more significant compared with non-irradiated U251 cells(p60Co γ-irradiation can enhance the inhibitory efficiency in U251 cell line. (authors)

  18. Transfection of p27 kip1 enhances radiosensitivity induced by 60Coγ-irradiation in hepatocellular carcinoma HepG2 cell line

    Institute of Scientific and Technical Information of China (English)

    Xiao-Xiang Guan; Long-Bang Chen; Gui-Xia Ding; Wei De; Ai-Hua Zhang

    2004-01-01

    AIM: To study the cell cycle alterations of human hepatoma cell line HepG2 in vitro after 60Co γ-irradiation and further to examine the mechanisms underlying the enhancement of radiosensitivity to γ-irradiation in HepG2 transiently transfected with wild type p27kip1.METHODS: The proliferation of HepG2 cells was evaluated with MTT assay, and the cell cycle profile and apoptosis were assessed by cell morphology, DNA fragmentation analysis and flow cytometry. HepG2 cells were transfected with p27kip1 wild type by using Lipofectamine (LF2000), and the expression and subcellular localization of p27kip1 in HepG2were detected by immunocytochemistry.RESULTS: 60Co γ-irradiation inhibited the growth of HepG2cells in a dose-dependent manner. Apoptosis of HepG2 cells was induced 48 h after γ ray exposure. Furthermore research was carried out to induce exogenous expression of p27kip1in HepG2. The expression of p27kip1 induced G0/G1 phase arrest in HepG2 cells. The overexpression of p27kip1 enhanced 60Co γ-irradiation-induced radiosensitivity in HepG2 cells.CONCLUSION: Overexpression of p27kip1 is a rational approach to improve conventional radiotherapy outcomes, which may be a possible strategy for human hepatoma therapy.

  19. Action of Bothrops moojeni venom and its L-amino acid oxidase fraction, treated with 60Co gamma rays, in Leishmania spp

    International Nuclear Information System (INIS)

    Bothrops moojeni venom showed an anti leishmania activity in vitro, as determined by a cell viability assay using the reduction of MTT. After venom purification, by chromatography techniques, the fractions with anti leishmania and L-amino acid oxidase activities, eluted in the same positions. The molecular weight of the enzyme was estimated to be 140 kDa by molecular exclusion chromatography, and 69 kDa, by SDS-PAGE, migrating as a single band, with an isoelectric point of 4.8 as determined by isoelectric focusing. The purified LAO from B. moojeni venom, 135-fold more active than crude venom, showed homo dimeric constitution, and was active against Leishmania spp from the New World, with an effective concentration against L(L). amazonensis of 1.80 μg/ml (EC50), L.(V.) panamensis (0.78 |μg/ml) and L.(L.) chagasi (0.63 (μg/ml). Ultrastructural studies of promastigotes affected by LAO demonstrated cell death, with edema in several organelles such as mitochondria and nuclear membrane, before cell disruption and necrosis. The action of LAO was demonstrated to be hydrogen peroxide-dependent. Studies with LLCMK-2 cells, treated with LAO, showed a toxic effect, with an EC50 of 11|μg/ml. Irradiation of LAO with 60Co gamma rays, did not affect its whole oxidative activity, neither detoxified the enzyme. Amastigotes treated with LAO were not affected by its hydrogen peroxide, otherwise, the exogenous product, killed amastigotes with an EC50 of 0.67mM. These data could be of help in the development of alternative therapeutic approaches to the treatment of leishmaniasis. (author)

  20. The response to climate factors for the different specificity in M2 physiology of 60Co γ-ray irradiated flowers

    International Nuclear Information System (INIS)

    Physiology and climate factor of different M2 flower (Begonia tuberhybrida Voss and Dahlia pinnata Cav root) after 60Co γ-ray irradiated were determined. The result showed that transpiration rate, stoma conductance, intercellular CO2 concentration of M2 of Dahlia pinnata Cav are affected obviously with climate factors, however, effect on the photosynthetic speed was not found, and M2 of Begonia tuberhybrida Voss was not significant for physiology to climate

  1. Differential gene expression in human fibroblasts after alpha-particle emitter (211)At compared with (60)Co irradiation

    DEFF Research Database (Denmark)

    Danielsson, Anna; Claesson, Kristina; Parris, Toshima Z;

    2013-01-01

    trastuzumab monoclonal antibody (0.25, 0.5, and 1 Gy) and (60)Co (1, 2, and 3 Gy). Results: We report gene expression profiles that distinguish the effect different radiation qualities and absorbed doses have on cellular functions in human fibroblasts. In addition, we identified commonly expressed transcripts...

  2. The effects of chloramphenicol and 60Co irradiation on the experimental mycosis in mice inoculated intragastrically with two kinds of pathogenic yeast-like fungi

    International Nuclear Information System (INIS)

    Two kinds of pathogenic yeast, Cryptococcus neoformans and Candida albicans were inoculated into the stomachs of mice. The effects of intragastric administration of chloramphenicol (CM) and systemic irradiation with 60Co on the acceralation of infection were studied in intragastrically inoculated mice. When Cryptococcus neoformans were simply inoculated, it was difficult for them to reside in the alimentary canal to cause infection. In case of candida albicans inoculated simply, they were also unable to induce infection though they remained in the alimentary canal for a long time. In the experiment combining intragastric administration of the fungi and CM some mice contracted the disease and died. The effect of CM in causing infection was not proved. In the experiments combining 60Co irradiation and intragastric administration of CM and fungi, a high incidence of fungus infection was noted with both Cryptococcus neoformans and Candida albicans. Fungus lesions were observed in many organs, and in all of the mice which died systemic fungus lesions were noted. It was shown that systemic irradiation with 60Co had a specific effect on facilitating the infection. In these studies no difference was observed in the incidence of the fungus disease in respect of the origin of the causative fungi. (J.P.N.)

  3. (60)Co in cast steel matrix: A European interlaboratory comparison for the characterisation of new activity standards for calibration of gamma-ray spectrometers in metallurgy.

    Science.gov (United States)

    Tzika, Faidra; Burda, Oleksiy; Hult, Mikael; Arnold, Dirk; Marroyo, Belén Caro; Dryák, Pavel; Fazio, Aldo; Ferreux, Laurent; García-Toraño, Eduardo; Javornik, Andrej; Klemola, Seppo; Luca, Aurelian; Moser, Hannah; Nečemer, Marijan; Peyrés, Virginia; Reis, Mario; Silva, Lidia; Šolc, Jaroslav; Svec, Anton; Tyminski, Zbigniew; Vodenik, Branko; Wätjen, Uwe

    2016-08-01

    Two series of activity standards of (60)Co in cast steel matrix, developed for the calibration of gamma-ray spectrometry systems in the metallurgical sector, were characterised using a European interlaboratory comparison among twelve National Metrology Institutes and one international organisation. The first standard, consisting of 14 disc shaped samples, was cast from steel contaminated during production ("originally"), and the second, consisting of 15 similar discs, from artificially-contaminated ("spiked") steel. The reference activity concentrations of (60)Co in the cast steel standards were (1.077±0.019) Bqg(-1) on 1 January 2013 12h00 UT and (1.483±0.022) Bqg(-1) on 1 June 2013 12h00 UT, respectively.

  4. (60)Co in cast steel matrix: A European interlaboratory comparison for the characterisation of new activity standards for calibration of gamma-ray spectrometers in metallurgy.

    Science.gov (United States)

    Tzika, Faidra; Burda, Oleksiy; Hult, Mikael; Arnold, Dirk; Marroyo, Belén Caro; Dryák, Pavel; Fazio, Aldo; Ferreux, Laurent; García-Toraño, Eduardo; Javornik, Andrej; Klemola, Seppo; Luca, Aurelian; Moser, Hannah; Nečemer, Marijan; Peyrés, Virginia; Reis, Mario; Silva, Lidia; Šolc, Jaroslav; Svec, Anton; Tyminski, Zbigniew; Vodenik, Branko; Wätjen, Uwe

    2016-08-01

    Two series of activity standards of (60)Co in cast steel matrix, developed for the calibration of gamma-ray spectrometry systems in the metallurgical sector, were characterised using a European interlaboratory comparison among twelve National Metrology Institutes and one international organisation. The first standard, consisting of 14 disc shaped samples, was cast from steel contaminated during production ("originally"), and the second, consisting of 15 similar discs, from artificially-contaminated ("spiked") steel. The reference activity concentrations of (60)Co in the cast steel standards were (1.077±0.019) Bqg(-1) on 1 January 2013 12h00 UT and (1.483±0.022) Bqg(-1) on 1 June 2013 12h00 UT, respectively. PMID:27236833

  5. Description of morphologic characters in avocado trees (Persea americana. Mill) var. Hass, submitted to gamma radiation of 60 Co

    International Nuclear Information System (INIS)

    It was carried out the characterization of 77 trees of avocado ''Hass'' subjected to gamma radiation of Co60, in doses of 0, 5, 10,15, 20 and 25 Gy based on previous studies of radiosensitivity with ends of improvement located in the experimental center ''La Labor'' belonging to the foundation Salvador Sanchez Colin. CICTAMEX. S C. in Temascaltepec, Mexico. It was carried out the morphological characterization of this variety according to the nomenclature settled down by the International Office of Genetic Resources (IBPGRI), registering 27 variables for the description of the tree, 33 for description of the fruit and 14 for the characterization of the seed. Regarding the architectural characterization 10 variables were evaluated. Using gamma radiation of Co60 in the doses of 15 and 20 Gy it was detected a reduction of 22% in the portage of the tree, likewise had reduction the diameter of the trunk and of the foliage. It was found that the reduction in the behavior of the tree induces to a bigger variation of the form of the same one, in the distribution of the branches in the form of the fruit and in the form of the seed you Also detects a remarkable increment in the productivity of some hoist irradiated regarding the architecture of the tree one observes that the angle of inclination of the branches increase when being increased the radiation dose and that the longitude of the annual section of growth decreased significantly in the doses of 20 and 25 Gy. One observes a significant Increment in the I number of buds prolepticos in those hoist irradiated in the I finish mbdulo of rhythmic growth. Io that indicates a change substantial in the I inhabit of growth With the purpose of determining if the changes in morphology and architecture of the tree corresponded with the modification at level meristematico, they were carried out observations to the court microscope of having knitted apical vegetative meristematico in samples of you hoist of all the treatments

  6. Effect of 60Co γ irradiation with seed and shoot-tip of Brassica campestris L. var on its culture in vitro

    International Nuclear Information System (INIS)

    The survival rate in vitro of shoot-tips of Brassica campestris L. var from seeds irradiated by 60Co γ-rays decreased with the increase of dose. Irradiation inhibited proliferation of shoot-tip, induction of callus from cotyledons and differentiation of the callus. The age of explant contributed to the effect of irradiation in the culture. Irradiation stimulated the proliferation of shoot-tip with dose less than 50 Gy. Based on the effect of irradiation in the tissue culture, the effective dose recommended was about 200 Gy for seeds, 50-100 Gy for pre-soaked germinating seeds and 40-70 Gy for shoot-tips in vitro, respectively

  7. IMMUNE TOLERANCE INDUCED BY GAMMA-RAY IRRADIATION

    Institute of Scientific and Technical Information of China (English)

    练燕; 王延江; 粟永萍; 冉新泽; 艾国平; 刘晓宏; 郭朝华; 程天民

    2003-01-01

    Objective: To detect the existence of immune tolerance induced by gamma-ray irradiation. Methods: Peritoneal cells were harvested from mice subjected to 5 Gy 60Co gamma-ray total body irradiation at 3d, 7d, 15d and 30d, then their counts, morphological changes and IL-12 gene expression were investigated. Results: After irradiation, the peritoneal cells were sharply reduced, the cell morphology shifted from round-like to polymorphic and fusiform with some processes, expression of IL-12 p35 was seriously suppressed, while that of IL-12 p40 greatly enhanced. Conclusion: Our data highly suggest that the gamma-ray irradiation could potentially induce dendritic cell (DC) commitment and immune tolerance.

  8. Study about the sensibility in vitro of different strains of Vibrio cholera 01 exposed to 60 Co gamma radiation

    International Nuclear Information System (INIS)

    The presence of some microorganisms in food, or the metabolites originated during their own multiplication may bring several diseases to humans: intoxications and food borne infections. Among the agents that may cause those diseases, we find Vibrio cholerae 01. In this experiment, the studies are focused on the radiosensibility in vitro of four strains of V. cholerae 01, exposed to different doses of ionizing radiation of 60 Co. The results are compared with other data related to bacterial food borne diseases, including water. (author)

  9. Comparisons of the standards for air kerma of the PTB and the BIPM for {sup 60}Co and {sup 137}Cs gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Allisy-Roberts, P.J.; Burns, D.T. [Bureau International des Poids et Mesures (BIPM), 92 - Sevres (France); Buermann, L.; Kramer, H.M. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    2005-11-15

    Direct comparisons of the standards for air kerma of the Physikalisch-Technische Bundesanstalt (PTB, Germany) and of the Bureau International des Poids et Mesures (BIPM) were carried out in the {sup 60}Co and {sup 137} Cs radiation beams of the BIPM in 2000. The results, expressed as ratios of the PTB and the BIPM standards for air kerma, indicate a relative difference in {sup 60}Co of 9.9 x 10{sup -3} with a combined standard uncertainty of 1.8 x 10{sup -3}, and in {sup 137}Cs of 6.4 x 10{sup -3} with a combined standard uncertainty of 2.8 x 10{sup -3}. The earlier comparisons in {sup 60}Co {gamma} rays made in 1971 (direct) and 1989 (indirect) resulted in an agreement of the two standards within 2 x 10{sup -3}. The differences obtained now are due to the application of new correction factors for wall effects and point source non-uniformity of the beam, k{sub wall} and k{sub pn}, for the PTB standards, which were calculated using Monte Carlo methods. (authors)

  10. Change of microflora of two starch samples by gamma irradiation

    International Nuclear Information System (INIS)

    Starch is the basic component of a larger number of manufactured foods. The disinfection of such a powder by 60Co is studied here. Gamma irradiation of two starch samples with different degrees of contamination allows the assumption that, in most cases, good radio-pasteurization can be achieved with 300 krad. The radio-pasteurization doses (varying from 300 to 600 krad) are a function of the initial contamination. Irradiation effects are spectacular with moulds. Activation of spores of some Clostridium species leads us to recommend an irradiation level higher than 200 krad. The most resistant organisms to gamma irradiation are the aerobic and anaerobic sporulated bacteria. The thermophilic forms are the most important. Spores of Bacillus, chiefly Bacillus licheniformis and Bacillus brevis, are the most frequent bacteria. Storage of irradiated starch at room temperature has little effect upon the number of revivable survivors. (orig.)

  11. Effect of hydrogen on change carrier dissipation in 60Co irradiated by γ-quanta and non-alloyed n-type GaAs

    International Nuclear Information System (INIS)

    The pretreatment in hydrogen plasma (the hydrogenation) influences on the charge carrier dissipation processes in the non-alloyed gallium arsenide of n-type with no = (5...7) centre dot 1015 cm-3 and μo = (5...6) centre dot 10 13 cm2 / (V centre dot c) irradiated by γ-quantum 60Co was studied. The comparison of experimental dependence μ (T) with the designed one in the temperature range 77...291 K for non-hydrogenized and hydrogenized non irradiated and γ-quantum irradiated crystals was carried out. It is shown that the main dissipative mechanism that determine the charged carrier mobility in the non hydrogenized material is the dissipation on the charged centers - the radiation defects in the γ-quantum irradiated GaAs; the presence of double ionized defects is possible

  12. Evaluation of immunity and protection induced in experimental models by soluble extract of Toxoplasma gondii tachyzoites irradiated by 60Co

    International Nuclear Information System (INIS)

    Toxoplasmosis affects 1/3 of the human population and only a vaccine for veterinary use. Gamma radiation alters the proteins making them more immunogenic by oxidation and better antigen presentation in the absence of adjuvants. Radiate soluble extract of RH strain tachyzoites of T. gondii (AgTg), and evaluate its use as a vaccine in BALB/c. Doses below 500Gy not affected and destroyed 2000Gy doses above extract, whereas animals immunized with irradiated extract at 1000, 1500 and 2000Gy had more of specific IgG avidity , compared to native AgTg (p<0,05) . AgTg 1500GY the immunized animals had increased proliferation of splenocytes, phenotyped as CD3+CD4+, CD3+CD8+ and B-lymphocytes immunized animals compared to the native AgTg . Animals immunized by AgTg 1500GY after challenge with strain ME- 49 cystogenic showed lower number of brain cysts and greater survival after challenge with virulent RH. Ionizing radiation in extracts of T. gondii increases the immune response and immune memory in the absence of adjuvants. (author)

  13. INCASOY-35: PRIMERA VARIEDAD DE SOYA OBTENIDA EN CUBA A PARTIR DEL EMPLEO DE TÉCNICAS DE IRRADIACIÓN DE RAYOS GAMMA DE 60Co

    Directory of Open Access Journals (Sweden)

    R. Ortiz

    2005-01-01

    Full Text Available La variedad INCASoy-35 fue obtenida a partir de la irradiación de semillas de la variedad INCASoy-15 con dosis de 240 Gy de rayos gamma 60Co; esta variedad se adapta a siembras de primavera, verano e invierno y puede alcanzar rendimientos de 3 t.ha-1 de granos. Tolera las principales plagas y enfermedades y, en especial, resiste el ataque de nemátodos Meloidogyne incognita. En la época adversa de primavera, las semillas han mostrado tolerancia al deterioro. Tiene capacidad de garantizar altas producciones con bajos insumos, por lo que resulta factible para la agricultura cubana.

  14. Soil compaction and gamma radiation ({sup 60}Co) in the development of the cowpea beans [Vigna unguiculata, (L) Walp]; Compactacao do solo e radiacao gama ({sup 60}Co) no desenvolvimento do feijao caupi [Vigna unguiculata, (L) Walp

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Eliane Ferreira; Colaco, Waldeciro [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Radioagronomia]. E-mails: aroucha@ufpe.br; wcolaco@ufpe.br

    2005-08-15

    The objective is to investigate the effect of compaction and increased doses of gamma radiation on the development of cowpea [Vigna unguiculata, (L) Walp] var. IPA-206 cultivated in a Neossolo fluvic soil, artificially compacted. Significant differences were observed in plant height, with the increase doses in soil density (1.30 Mg.m{sup -3} - compacted soil and 1.70 Mg.m{sup -3} - non-compacted soil), and in response to increased doses of irradiation (y-rays) [ [0, 100, 200 and 300 Gy). The diameter of the stem was significantly reduced in response to the increase in soil density, however the same did not occur in relation to the doses of irradiation (y-rays) holding capacity of the soil was reduced in response to the increase in soil density. (author)

  15. Comparison of the standards of air kerma of the OMH and the BIPM for 60Co gamma radiation

    International Nuclear Information System (INIS)

    A direct comparison between the standards for air kerma of the Orszagos Meresugyi Hivatal (OMH) and of the Bureau International des Poids et Mesures (BIPM) has been carried out in the 60Co radiation beams of the BIPM. The result, expressed as a ratio of the OMH and the BIPM standards for air kerma, indicates a relative difference of 10.9 x 10-3 with a combined standard uncertainty of 2.2 x 10-3. This new result agrees at the level of 0.4 x 10-3 with the earlier direct comparisons performed in 1986 and 1994, as modified in 2001 by the application of wall and axial non-uniformity correction factors, calculated for the OMH standards using the Monte Carlo method. (authors)

  16. Effects of 60Co γ-ray irradiation on microstructure and ferroelectric properties of Bi3.25La0.75Ti3O12 thin films

    Science.gov (United States)

    Wang, Zan; Jiang, Wei; Li, San-xi; Tong, Jun-sheng

    2016-01-01

    Bi3.25La0.75Ti3O12 (BLT) thin films were deposited on Pt/Ti/SiO2/Si substrates through sol-gel method. Films underwent 60Co γ-ray irradiation with different doses; 0, 50, 100 and 150 kGy, respectively. Impacts of γ-ray on the microstructure, ferroelectric properties, leakage current density and fatigue characteristic were studied in detail. The results of SEM images show that grain patterns become irregular. Remnant polarization (2Pr) and coercive field (2Ec) decrease with irradiation dose increase. C-V curves reveal obvious asymmetry along y-axis. The irradiated thin films display lower leakage current density and fatigue endurance up to more than 1010 switching cycles. These results suggest that radiation can improve the film performance in some areas.

  17. Supplementary comparison CCRI(I)-S2 of standards for absorbed dose to water in 60Co gamma radiation at radiation processing dose levels

    DEFF Research Database (Denmark)

    Burns, D. T.; Allisy-Roberts, P. J.; Desrosiers, M. F.;

    2011-01-01

    Eight national standards for absorbed dose to water in 60Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized by the B......Eight national standards for absorbed dose to water in 60Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized...... by the Bureau International des Poids et Mesures, who also participated at the lowest dose level using their radiotherapy-level standard for the same quantity. The national standards are in general agreement within the standard uncertainties, which are in the range from 1 to 2 parts in 102. Evidence of a dose...

  18. Calculation of direct effects of 60Co gamma rays on the different DNA structural levels: A simulation study using the Geant4-DNA toolkit

    International Nuclear Information System (INIS)

    In this study, simple single strand breaks (SSB) and double strand breaks (DSB) due to direct effects of the secondary electron spectrum of 60Co gamma rays on different organizational levels of a volume model of the B-DNA conformation have been calculated using the Geant4-DNA toolkit. Result of this study for the direct DSB yield shows a good agreement with other theoretical and experimental results obtained by both photons and their secondary electrons; however, in the case of SSB a noticeable difference can be observed. Moreover, regarding the almost constant yields of the direct strand breaks in the different structural levels of the DNA, calculated in this work, and compared with some theoretical studies, it can be deduced that the direct strand breaks yields depend mainly on the primary double helix structure of the DNA and the higher-order structures cannot have a noticeable effect on the direct DNA damage inductions by 60Co gamma rays. In contrast, a direct dependency between the direct SSB and DSB yields and the volume of the DNA structure has been found. Also, a further study on the histone proteins showed that they can play an important role in the trapping of low energy electrons without any significant effect on the direct DNA strand breaks inductions, at least in the range of energies used in the current study

  19. Calculation of direct effects of {sup 60}Co gamma rays on the different DNA structural levels: A simulation study using the Geant4-DNA toolkit

    Energy Technology Data Exchange (ETDEWEB)

    Tajik, Marjan; Rozatian, Amir S.H. [Department of Physics, University of Isfahan, Hezar Jarib Street, Isfahan 81746-73441 (Iran, Islamic Republic of); Semsarha, Farid, E-mail: Semsarha@ibb.ut.ac.ir [Institute of Biochemistry and Biophysics (IBB), University of Tehran, P.O. Box: 13145-1384, Tehran (Iran, Islamic Republic of)

    2015-03-01

    In this study, simple single strand breaks (SSB) and double strand breaks (DSB) due to direct effects of the secondary electron spectrum of {sup 60}Co gamma rays on different organizational levels of a volume model of the B-DNA conformation have been calculated using the Geant4-DNA toolkit. Result of this study for the direct DSB yield shows a good agreement with other theoretical and experimental results obtained by both photons and their secondary electrons; however, in the case of SSB a noticeable difference can be observed. Moreover, regarding the almost constant yields of the direct strand breaks in the different structural levels of the DNA, calculated in this work, and compared with some theoretical studies, it can be deduced that the direct strand breaks yields depend mainly on the primary double helix structure of the DNA and the higher-order structures cannot have a noticeable effect on the direct DNA damage inductions by {sup 60}Co gamma rays. In contrast, a direct dependency between the direct SSB and DSB yields and the volume of the DNA structure has been found. Also, a further study on the histone proteins showed that they can play an important role in the trapping of low energy electrons without any significant effect on the direct DNA strand breaks inductions, at least in the range of energies used in the current study.

  20. Inactivation of citrus tristeza virus by gamma ray irradiation

    International Nuclear Information System (INIS)

    The total exposure of gamma ray and the intensity of gamma ray per hour for the inactivation of citrus tristeza virus (CTV) and also the effect on citrus tissues are described. The budwoods of Morita navel orange infected with a severe seedling-yellow strain of CTV were irradiated with gamma ray from a 60Co source for 20 -- 52 hours. The buds or small tissue pieces of the irradiated budwoods were subsequently grafted onto Mexcan lime. CTV was easily inactivated by the irradiation from 10 to 18 kR for from 20 to 52 hours. The higher the total exposure, the higher the rate of inactivation. The CTV in the budwoods was almost inactivated after the irradiation with 20 kR. When the total exposure to gamma ray on budwoods was the same, CTV was more efficiently inactivated by the irradiation for long period with low intensity of gamma ray per hour than that for short period with high intensity per hour. Gamma ray irradiation was effective to eliminate CTV from citrus tissues. (Mori, K.)

  1. Gamma ({sup 60}CO) radiation effects on arcelin protein and evaluation of bean lineages against Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boh.) (Col.: Bruchidae);Efeito da radiacao gama ({sup 60}CO) sobre a proteina arcelina e avaliacao de linhagens de feijoeiro a Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boh.) (Col.: Bruchidae)

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, Ana Claudia Girardo

    2006-07-01

    The resistance of arcelin carrying seeds of bean lineages (Phaseolus vulgaris L.) against the bean weevils Acanthoscelides obtectus (Say, 1831) and Zabrotes subfasciatus (Bohemann, 1833) (Coleoptera: Bruchidae), and the influence of gamma radiation ({sup 60}CO) on the manifestation of arcelin resistance to Z. subfasciatus were verified. Laboratorial tests, in choice and non-choice tests, with wild specimens carrying Arc-1, Arc-2, Arc-3, Arc-4, Raz-56 and Raz-59 (with Arc-5 alleles) and commercial lineages as control IAC - Carioca and IAC - Arua were conducted. Statistical design was completely randomized, with five repetitions, with 10 g of grains from each lineage samples by portion. Attractiveness, oviposition, emergence, mortality, adults' weigh and longevity, developing period, sexual rate, seeds' weigh loss, infestation and fecundity (Z. subfasciatus) were observed. Gamma radiation doses irradiations, in general, haven't affected the resistance manifestation of lineages carrying arcelin protein variants against the Z. subfasciatus bean weevil, thus, joint application use of both control methods can be recommended. Raz-56 lineage showed high resistance of the antibiosis types and non-preference for oviposition and feeding to Z. subfasciatus, while Raz-59 showed antibiosis and non-preference for feeding, and both (Raz-56 and Raz-59) showed intermediate resistance to A. obtectus, against which lineage Arc-2 was the most harmful to its development, expressing non-preference to feeding and/or antibiosis. (author)

  2. Dose-rate effect on chromosomal aberrations induced by 60Co γ-rays irradiation in human peripheral blood lymphocyte

    International Nuclear Information System (INIS)

    To estimate exactly the biological dose of persons exposed to different dose rate, human peripheral blood was exposed to 60Co γ-rays in vitro at low, middle and high dose rates respectively and chromosome samples were prepared, then dose-response curves were established according to the dicentrics and ring frequencies. The result showed that the aberration frequency at same dose level increased with dose rate and there was an obvious dose-rate effect. Absorbed dose estimated with low dose-rate dose-response curve was higher markedly than that with high dose-rate dose-response curve. So, considering the effect of dose-rate, approximate dose-rate dose-response curve should be chosen when absorbed dose estimation and the result will be credible. (authors)

  3. Differential Expression of Retrotransposon WIS 2-1A Response to Vacuum, Low-Energy N+ Implantation and 60Coγ-ray Irradiation in Wheat

    Science.gov (United States)

    Zhao, Huiru; Gu, Yunhong; Ya, Huiyuan; Jiao, Zhen; Qin, Guangyong

    2009-02-01

    Mutagenesis and retrotransposons have a close relationship, but little attention has been paid yet to the activity of retrotransposons produced by physical mutagens. The variation of retrotransposon WIS 2-1A activity in wheat (Triticum aestivum L.) embryos at three different growth times (30 h, 45 h and 60 h) was investigated after they had been treated with N+ implantation in a vacuum of 5 × 10-2 Pa and irradiation by 60Coγ-ray respectively. For each of the three growth times the expression of WIS 2-1A showed almost entirely a same trend of downregulation, upregulation, then downregulation, and upregulation again with the increase in dose of N+ implantation, but the expression appeared irregular with the increase in irradiation of 60Coγ-ray. In conclusion, the acutely activating effect of WIS 2-1A stimulated by vacuum and high dose N+ implantation within a shorter incubation time may provide a convenient tool to advance the research on mutagenic breeding and function genes.

  4. Differential Expression of Retrotransposon WIS 2-1A Response to Vacuum,Low-Energy N+ Implantation and 60Coγ-ray Irradiation in Wheat

    Institute of Scientific and Technical Information of China (English)

    ZHAO Huiru; GU Yunhong; YA Huiyuan; JIAO Zhen; QIN Guangyong

    2009-01-01

    Mutagenesis and retrotransposons have a close relationship,but little attention has been paid yet to the activity of rtrotransposons produced by physical mutagens. The variation of retrotransposon WIS 2-1A activity in wheat(Triticum aestivum L.)embryos at three different growth times(30 h,45 h and 60 h)was investigated after they had been treated with N+ implantation in a vacuum of 5x10-2 Pa and irradiation by 60Coγ-ray respectively.For each of the three growth times the expression of WIS 2-1A showed almost entirely a same trend of downregulation,upregulation,then downregulation,and upregulation again with the increase in dose of N+ implantation,but the expression appeared irregular with the increase in irradiation of 60Coγ-ray.In conclusion,the acutely activating effect of WIS 2-1A stimulated by vacuum and high dose N+ implantation within a shorter incubation time may provide a convenient tool to advance the research on mutagenic breeding and function genes.

  5. Rapid rejoining of DNA strand breaks in resting human lymphocytes after irradiation by low doses of 60Co γ rays or 14.6-MeV neutrons

    International Nuclear Information System (INIS)

    The production and repair of DNA strand breaks was studied in human lymphocytes by means of a sensitive fluorometric technique. Lymphocytes were isolated by conventional methods and air-equilibrated suspensions were irradiated by low doses (less than or equal to 2 Gy) of either 60Co γ rays or 14.6-MeV neutrons at 00C. The apparent yield of initial strand breaks induced by neutrons was only 36% of that induced by γ rays, in agreement with the observations of other workers. Resting lymphocytes were found to be proficient in their ability to rejoin γ-induced strand breaks at 370C; rejoining followed biphasic kinetics, with 70% of the breaks disappearing with a half-life of about 3 min. Although the initial number of breaks induced by neutron irradiation was low, after 20 min of incubation the residual number of breaks was very similar for the two forms of radiation

  6. Gamma irradiators for radiation processing

    International Nuclear Information System (INIS)

    Radiation technology is one of the most important fields which the IAEA supports and promotes, and has several programmes that facilitate its use in the developing Member States. In view of this mandate, this Booklet on 'Gamma Irradiators for Radiation Processing' is prepared which describes variety of gamma irradiators that can be used for radiation processing applications. It is intended to present description of general principles of design and operation of the gamma irradiators available currently for industrial use. It aims at providing information to industrial end users to familiarise them with the technology, with the hope that the information contained here would assist them in selecting the most optimum irradiator for their needs. Correct selection affects not only the ease of operation but also yields higher efficiency, and thus improved economy. The Booklet is also intended for promoting radiation processing in general to governments and general public

  7. 60Coγ射线辐照不同麻种种子的细胞学效应%Cytological Effects on Seeds of Hibiscus cannabinus and Cannabis sativa Irradiated by 60Coγ ray

    Institute of Scientific and Technical Information of China (English)

    周立人; 吴雪琴; 魏晓飞; 李布青

    2003-01-01

    通过5种不同剂量的60Coγ射线对两个不同麻种3个品种材料的种子辐照效应研究表明,低剂量的60Coγ射线辐照能促进麻类作物根尖细胞的有丝分裂.但随着γ射线辐照剂量的增加,根尖细胞有丝分裂指数呈不同程度的下降趋势.60Coγ射线辐照能诱发根尖细胞的染色体畸变和核畸变,出现桥、断片、落后染色体、微核、双核、小核等多种畸变类型,并且辐照剂量越大,根尖细胞畸变类型越多,变异频率越高.研究结果还表明不同麻种、同一麻种不同品种对60Coγ射线的辐射敏感性不同,红麻中杂红305最强,红麻福红2号次之,大麻最弱.

  8. Optimization of process parameters for the inactivation of Lactobacillus sporogenes in tomato paste with ultrasound and 60Co- γ irradiation using response surface methodology

    Science.gov (United States)

    Ye, Sheng-Ying; Qiu, Yuan-Xin; Song, Xian-Liang; Luo, Shu-Can

    2009-03-01

    The processing parameters for ultrasound and 60Co- γ irradiation were optimized for their ability to inactivate Lactobacillus sporogenes in tomato paste using a systematic experimental design based on response surface methodology. Ultrasonic power, ultrasonic processing time and irradiation dose were explored and a central composite rotation design was adopted as the experimental plan, and a least-squares regression model was obtained. The significant influential factors for the inactivation rate of L. sporogenes were obtained from the quadratic model and the t-test analyses for each process parameter. Confirmation of the experimental results indicated that the proposed model was reasonably accurate and could be used to describe the efficacy of the treatments for inactivating L. sporogenes within the limits of the factors studied. The optimized processing parameters were found to be an ultrasonic power of 120 W with a processing time of 25 min and an irradiation dose of 6.5 kGy. These were measured under the constraints of parameter limitation, based on the Monte Carlo searching method and the quadratic model of the response surface methodology, including the a/ b value of the Hunter color scale of tomato paste. Nevertheless, the ultrasound treatment prior to irradiation for the inactivation of L. sporogenes in tomato paste was unsuitable for reducing the irradiation dose.

  9. Gemstone dedicated gamma irradiation development

    Energy Technology Data Exchange (ETDEWEB)

    Omi, Nelson M.; Rela, Paulo R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: nminoru@ipen.br; prela@ipen.br

    2007-07-01

    The gemstones gamma irradiation process to enhance the color is widely accepted for the jewelry industry. These gems are processed in conventional industrial gamma irradiation plant which are optimized for other purposes, using underwater irradiation devices with high rejection rate due to its poor dose uniformity. A new conception design, which states the working principles and manufacturing ways of the device, was developed in this work. The suggested device's design is based on the rotation of cylindrical baskets and their translation in circular paths inside and outside a cylindrical source rack as a planetary system. The device is meant to perform the irradiation in the bottom of the source storage pool, where the sources remain always shielded by the water layer. The irradiator matches the Category III IAEA classification. To verify the physical viability of the basic principle, tests with rotating cylindrical baskets were performed in the Multipurpose Irradiator constructed in the CTR, IPEN. Also, simulations using the CADGAMMA software, adapted to simulate underwater irradiations, were performed. With the definitive optimized irradiator, the irradiation quality will be enhanced with better dose control and the production costs will be significantly lower than market prices due to the intended treatment device's optimization. This work presents some optimization parameters and the expected performance of the irradiator. (author)

  10. Effects of Pre-exposure of Mouse Pituitary with Low-dose 60Co γ-ray on Male Reproductive Endocrine Capacity Induced by Subsequent High-dose Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZhangHong; LiWenjian; JingXiaodong; LiuBing; MinFengling; ZhouQingming; XieYi

    2003-01-01

    To investigate the effects of pre-exposure of mouse pituitary with low-dose 60Co γ-ray on male reproductive endocrine capacity induced by subsequent high-dose irradiation, the pituitary of the B6C3F1 hybrid strain male mice were irradiated with 0.05 Gy of 60Co γ-ray as the pre-exposure dose (D1), and were then irradiated with 2 Gy of 60Co γ-ray as challenging irradiation dose (D2) at 4 h after per-exposure. Pituitary gonadotroping hormones --follicle-stimulating hormone (FSH) and luterinzing hormone (LH), serum testosterone, testis weight and sperm count were measured at 35th day after irradiation.

  11. Preparation and Characterization of Fe3O4 Magnetic Nano-particles by 60Co γ-ray Irradiation

    Institute of Scientific and Technical Information of China (English)

    Mingcheng YANG; Hongyan SONG; Chengshen ZHU; Suqin HE; Ya GAO

    2007-01-01

    By using a new method, 60C0 γ-ray irradiation, Fe3O4 magnetic nano-particles were successfully synthesized at room temperature under ambient pressure. The structure, morphology and magnetic properties of these nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM), respectively. The radiation formation mechanism was also discussed. The results show that the absorbed dose can greatly influence the structure, morphology and magnetic properties of the products. XRD and TEM studies show that the product prepared by γ-ray irradiation (10 kGy) is pure FesO4 phase and the mean diameter of these nano-particles is about 21 nm. The Fe3O4 nano-particles synthesized by γ-ray irradiation (10 kGy) are mainly in small cubic shape and the size uniformity of these particles is good.

  12. Change in the amino acid composition of calf skin collagen after. gamma. -irradiation in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Duzhenkova, N.A.; Savich, A.V. (Institut Biofiziki, Moscow (USSR))

    A study was made of the amino acid composition of calf skin collagen after ..gamma..-irradiation (/sup 60/Co) of 2.5x10/sup -6/ M aerated aqueous protein solution within the dose range from 30 to 2000 Gy. The radiosensitivity of amino acid residues was compared.

  13. Preliminary study on effects of 60Co γ-irradiation on video quality and the image de-noising methods

    International Nuclear Information System (INIS)

    There will be variable noises appear on images in video once the play device irradiated by γ-rays, so as to affect the image clarity. In order to eliminate the image noising, the affection mechanism of γ-irradiation on video-play device was studied in this paper and the methods to improve the image quality with both hardware and software were proposed by use of protection program and de-noising algorithm. The experimental results show that the scheme of video de-noising based on hardware and software can improve effectively the PSNR by 87.5 dB. (authors)

  14. Studies on progenitor cell compartments of 60Co irradiated and normal fetuses at 55 days of gestation

    International Nuclear Information System (INIS)

    Studies were performed on canine fetal tissues obtained from animals exposed to in vivo chronic irradiation and unexposed controls. CFU-GM, CFU-F and CFU-L assays were done using placental conditioned medium (PCM) or Concanavalin-A (Con-A) as the colony stimulating factor. Preliminary work using medium conditioned with canine spleen cells (SCM) was also begun which indicated that this colony stimulating factor greatly increases the number of colonies observed in both the CFU-GM and CFU-L assays. Chronic irradiation may adversely affect PCM responsive CFU-GM and CFU-F but not Con-A-reactive CFU-L

  15. Measurement of 60CO gamma radiation induced attenuation in multimode step-index POF at 530 nm

    Directory of Open Access Journals (Sweden)

    Kovačević Milan S.

    2013-01-01

    Full Text Available As optical fibres are used ever more extensively in space applications, nuclear industry, medicine and high-energy physics experiments, it has become essential to investigate the influence of ionizing radiation on their characteristics. In this work, the radiation-induced attenuation at 530 nm is investigated experimentally in step-index multimode polymethyl-methacrylate plastic optical fibres exposed to low dose-rate gamma radiation. Cumulative doses ranged from 50 Gy to 500 Gy. The radiation induced attenuation has been empirically found to obey the power law RIA= aDb, where D is the total radiation dose and a and b are the constants determined by fitting.

  16. Effects of {gamma} ({sup 60}Co) and {beta} ({sup 90}Sr) radiations in Chinese hamster ovarian cells (CHO-K1): induction of micronuclei and cell death; Efeitos das radiacoes {gamma} ({sup 60}Co) e {beta} ({sup 90}Sr) em celulas de ovario de hamster chines (CHO-K1): inducao de micronucleos e morte celular

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Daniella

    2003-07-01

    Among various types of ionising radiation, the beta emitter radionuclides are involved in many sectors of human activity, such as nuclear medicine, nuclear industries and biomedicine, with a consequent increased risk of accidental, occupational or therapeutic exposure. Despite their recognized importance, there is little information about the effect of beta particles at the cellular level when compared to other types of ionizing radiation. Thus, the objective of the present study was to evaluate the genotoxic and cytotoxic effects of {sup 90}Sr, a pure, highly energetic beta source, on CHO-K1 cells and to compare them with data obtained with {sup 60}Co. CHO-K1 cells irradiated with different doses (1.0, 2.5, 5.0, 7.5 Gy) of {sup 60}Co (0.34 Gy.min{sup -1}) and {sup 90}Sr (0.23 Gy.min{sup -1}) were processed for analysis of clonogenic death, induction of micronuclei (MN) and necrotic and apoptotic death. The survival curves obtained for both types of radiation were better fitted by the linear-quadratic model and were similar. However, the cytogenetic results showed that both the proportion of micronucleated cells and the magnitude of radioinduced lesions demonstrated by the analysis of MN distribution were significantly higher in cells irradiated with {sup 60}Co than in cells irradiated with {sup 90}Sr, whereas {sup 90}Sr was more damaging than {sup 60}Co in terms of cell death induction. Necrosis was the major type of death observed in CHO-K1 cells. The data obtained suggest that the low incidence of micronucleated cells after exposure to {sup 90}Sr may be a consequence of selective elimination of severely damaged cells from the population by the necrotic process at a higher rate than observed with {sup 60}Co exposure. The data obtained also demonstrated the need to use several parameters for a better estimate of cellular sensitivity to the action of genotoxic agents, which would be important in terms of radiobiology, oncology and therapeutics. (author)

  17. The use of ionising radiation from 60CO gamma source in controlling mouldiness in dried cocoa beans

    International Nuclear Information System (INIS)

    Mouldiness in stored cocoa beans in Ghana and the production of aflatoxin have been studied. Based on actual weight of discarded beans, mouldy beans have been estimated to constitute 0.13 % and 0.00002 % of marketable beans at the farmers' level and the buying agents' depots respectively in the Tafo District. This is contrasted with an estimated value of 0.16 % obtained in a questionnaire type study involving farmers. Estimated mouldy beans at the Tema port was 0.69 % per year (based on the cut test) representing a financial loss of $1,688,637.19 per year at $989/T should the mouldy beans be discarded. Fifty-eight (58) internally- and externally- borne fungal species were isolated from dried cocoa beans. Of these, forty-eight (48) were internally- borne and ten (10) were superficial. Twenty-nine (29) of the internally occurring fungi have been recorded for the first time on cocoa beans in Ghana. Twenty-six (26) of the fungi isolated belong to Aspergillus group. They included A. parasiticus and A. flavus, which can produce aflatoxins. Five (5) belong to Penicillium, eight (8) to Fusarium and nineteen (19) to other species. Ionising radiation effectively controlled fungi associated with mouldiness in cocoa beans in a dose - dependent manner. A radiation dose of 6 kGy completely inactivated the moulds. A. flavus and A. tamarii were the most radiation - resistant moulds encountered. The moisture content of the beans before, during and after irradiation influenced the effect of radiation. The relative humidity during storage and the type of packaging also influenced the radiation effect. Conidia of A. flavus subjected to moist heat at temperatures 20 0C to 60 0C for 2.5, 5 and 10 min respectively were not significantly affected by heating up to 50 0C. Heating an aqueous conidial suspension at 60 0C for at least 2.5 min reduced the number of fungal colonies by at least 5 log cycles when the suspension was assayed on agar plate media. Heating at 59 0C for 10 min

  18. Gamma irradiation service in Mexico

    International Nuclear Information System (INIS)

    In 1980 it was installed in Mexico, on the National Institute of Nuclear Research, an irradiator model J S-6500 of a canadian manufacture. Actually, this is the greatest plant in the Mexican Republic that offers a gamma irradiation process at commercial level to diverse industries. However, seeing that the demand for sterilize those products were not so much as the irradiation capacity it was opted by the incursion in other types of products. During 17 years had been irradiated a great variety of products grouped of the following form: dehydrated foods, disposable products for medical use, cosmetics, medicaments, various. Nowadays the capacity of the irradiator is saturated virtue of it is operated the 24 hours during the 365 days of the year and only its operation is suspended by the preventive and corrective maintenance. However, the fresh food market does not be attended since this irradiator was designed for doses greater than 10 kGy (1.0 Mrad)

  19. Study about the sensibility in vitro of different strains of Vibrio cholera 01 exposed to 60 Co gamma radiation; Estudo da sensibilidade in vitro de diferentes cepas de Vibio cholerae 01 a radiacao gama de 60Co

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Ivany Rodrigues de [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Servicos de Saude; Gelli, Dilma Scala; Jakabi, Miyoko [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Secao de Microbiologia; Mastro, Nelida Lucia del [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: nlmastro@net.ipen.br

    1998-07-01

    The presence of some microorganisms in food, or the metabolites originated during their own multiplication may bring several diseases to humans: intoxications and food borne infections. Among the agents that may cause those diseases, we find Vibrio cholerae 01. In this experiment, the studies are focused on the radiosensibility in vitro of four strains of V. cholerae 01, exposed to different doses of ionizing radiation of {sup 60} Co. The results are compared with other data related to bacterial food borne diseases, including water. (author)

  20. 60Co γ-ray irradiation effect on germination and seedling growth of dry Buchloe dactyloides seeds

    International Nuclear Information System (INIS)

    The dry seeds of Buchloe dactyloides were irradiated by γ-ray at dose of 25-300 Gy. Seed germination and seedling characters were surveyed in laboratory and field. The results indicated that radiation could promote seed germination, and the optimum dose was 100 Gy. The dose of 150 Gy was the up limit to germination rate, root length and seedling height in field. When the radiation dose was bellow 100 Gy, the fresh weight of stems, leaves and roots of seedlings were increased. From this study, the recommended radiation does for Buchloe dactyloides dry seeds treatment was between 100-150 Gy for the purpose of promoting germination. (authors)

  1. Optimisation of radiolysis of Reactive Red 120 dye in aqueous solution using ionising (60)Co gamma radiation by response surface methodology.

    Science.gov (United States)

    Padmanaban, V C; Giri Nandagopal, M S; Achary, Anant; Vasudevan, V N; Selvaraju, N

    2016-01-01

    In recent years, employing radiation technology is gaining great interest in degradation of industrial effluents. In this work the possibility of using gamma irradiation to degrade Reactive Red 120 (C.I.292775) was explored. The effects of pH, dose of gamma irradiation and concentration of dye were examined and their interaction were also established based on their response. For the analysis and optimisation of variables, three factor three level Box-Wilson face centred central composite design (CCF) was used. Analysis of variance with R(2) = 0.9988, adjusted R(2) = 0.9981 and the adequate precision value of 122.303 indicates that the CCF model can be used. The coefficient of variation (0.54%) indicates the reliability of the model. The dose of gamma irradiation (kGy) and the concentration of dye (mg/L) showed significant effects on the degradation of RR 120, while a difference of 6 to 10% degradation was observed in extending the pH towards the acid or alkali range from pH 7.00. The maximum concentration of dye degraded was observed as 347.509 mg/L at initial pH: 7.0, dose of gamma irradiation: 5.94 kGy and initial concentration of dye: 500 mg/L. This predicted value was found to be in agreement with the experimental value on the optimised conditions. PMID:27332851

  2. Effects of 60CoIrradiation Intensity on Watermelon Seed Germination and Seedling Growth%60Co-γ辐射对西瓜种子萌发和幼苗生长的效应

    Institute of Scientific and Technical Information of China (English)

    李玉明; 杨世梅; 纪海波; 方春媛; 潘从祥; 陈年来

    2013-01-01

    In order to investigate the effects of different doses of 60Co-γ radiation on watermelon seed germination and seedling growth, watermelon seeds with different qualities of 12 varieties were used as the test materials to investigate the effects of six different doses of radiation on emergence rate, surviving rate, emergence time, cotyledon area, plant height and stem diameter. The results showed that medium size seeds of watermelon demonstrated a promoting effect on seedling growth under the dose of 200 Gy and 400 Gy. When the radiation dose exceed 600 Gy, all watermelon seeds showed the extremely significant level (P small seed > medium seeds.%为了探讨60Co-γ辐射剂量对不同质量西瓜种子萌发和幼苗生长的影响,以不同质量的12个西瓜品种干种子为材料,通过6个剂量的辐射处理,研究辐射剂量对西瓜干种子出苗率、存活率、出苗时间、子叶面积、株高及茎粗等的影响.结果表明,200和400 Gy辐射对中等种子出苗有促进作用,超过600 Gy都具有显著(P<0.05)抑制作用;随着辐射剂量的增加,植株出苗时间延长,幼苗生长缓慢;根据半致死剂量确定西瓜种子适宜辐射剂量为600~800 Gy.不同大小西瓜种子对60Co-γ辐射的敏感性表现为大种子>小种子>中等种子.

  3. Seeds of Camargue rice (Oryza Sativa L. Var Cigalon) and their responses to exposure to 60-Co gamma radiations. Study of the natural phenomenon of radiation protection

    International Nuclear Information System (INIS)

    Within the frame of a project aiming at improving a technique of experimental mutagenesis (seed processing by cobalt-60 gamma rays), this research thesis reports the radiobiological characterization of Cigalon rice seeds, the adjustment of techniques of radiation protection, and the definition of processing and irradiation conditions which could reduce the undesirable physiological effects of cobalt-60 gamma radiation on rice seeds. The author reports the study of variations of physiological radio-sensitivity. Damages are assessed by comparing the growth of irradiated seeds with that of non-irradiated seeds. The mechanism of radiation natural protection is studied by comparing an inhibition in distilled water at two temperatures (5 and 24 C) with that obtained with cysteamine (an efficient radiation protection compound)

  4. Gamma Irradiation of Polyesters Film

    International Nuclear Information System (INIS)

    Experimental investigations on the effects of gamma irradiation in air of aromatic polyesters are carried out, in order to evaluate the influence of aromatic density and the role of oxygen on the radiation resistance. The thermoplastic polyesters PolyEthyleneTerephthalate (PET), PolyButylene Terephthalate (PBT), PolyEthyleneNaphthalate (PEN), Poly1,4-cyclohexanedimethylen terephthalate-co-ethyleneterephthalate (PCT-co-ET) are moulded in thin films of 50 micron and irradiated at different absorbed doses, ranging from 0 to 1000 kGy, using a Co-60 gamma source. The structural changes in the polymers are studied by means of several physical-chemical and nuclear techniques. Electron Paramagnetic Resonance analyses are carried out to detect the radicals induced by irradiation and to follow their decay by oxygen permeation. Viscometric measurements show a similar trend for the different irradiated polyesters: in particular, chain scission induced by irradiation depends on the aromatic density contained in the polymer and shows a saturation effect at the highest doses. Positron Annihilation Lifetime Spectroscopy points out a decrease of the ortho-positronium signal caused by the production of oxidized species inhibiting the positronium formation. Finally, the experimental results obtained on the irradiated films are compared with previous studies carried out on the same polyesters moulded in sheets of 1-2 mm of thickness and γ-irradiated at the same adsorbed doses

  5. Utilization of an elite rice germplasm-Yangdao 6 with high combining ability created by 60Co γ-irradiation

    International Nuclear Information System (INIS)

    Yangdao 6, a new rice variety bred by irradiation induced mutation, is an elite Indica germplasm with a higher general combining ability (GCA) and specific combining ability (SCA) compared with other restorer lines in yield composing traits, including total grains per panicle, filling grains per panicle, seed setting, 1000-grain weight, grain plumpness, yield per plant, etc. Used as a parent with high yield, good quality and multi-resistance, it has a good probability for breeding super-high-yield hybrid combinations both for the 'two-line' and Honglian-type CMS lines. And as a restorer line, it accelerates both the breeding of hybrid combinations and routine cultivars with a mode of 'boat goes up as river rises'. (authors)

  6. The influence of α-amylase supplementation, γ-irradiation (60Co) as well as long time of storage of wheat grain on flour technological properties

    International Nuclear Information System (INIS)

    The varieties of winter wheat, Aria and Beta, were studied. The Aria variety was stored for the period of four years. The part of wheat grain from Beta variety was irradiated with γ rays (60Co). In extracts from wheat kernels and flour protein content, total α- and β-amylolytic activity as well as α-amylolytic activity were determined, α-amylases of native and fungal origin were added to the flour obtained from samples of stored wheat kernels (Aria), irradiated and non-irradiated (Beta). Consequently native α-amylase activity of flour increased by 25% and 50%, respectively. Extensive technological estimation of grain and flour with amylase supplements was carried out. The study included: sedimentation analysis, falling number test, milling experiment, farinogram and extensogram analyses, measurement of the degree of damaged starch and flour colour, as well as baking experiment. The obtained experimental loaves of bread were tested for their ability to remain fresh. It was found out that the stored grain flour was characterized by the highest α-amylolytic activity and the lowest falling number value, whereas the irradiated grain flour showed the highest degree of starch damage and water absorption. When α-amylase supplementation to doughs was not accompanied by either irradiation or storage of grain, it definitely changed their physical properties for the worse. The negative influence of native α-amylases appeared to be less significant than that of fungal α-amylases. The positive influence of α-amylase supplementations, especially of those increasing by 25% the native α-amylolytic activity of flour on volume, and freshness of loaves of bread was observed. (author)

  7. Effects of gamma irradiation on electric characteristics of power diodes

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Renata F.; Santos, Thais C. dos; Pascoalino, Kelly C.; Goncalves, Josemary A.C.; Tobias, Carmen C.B., E-mail: ccbueno@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    In this work we presented the preliminary results of a systematic study of direct voltage and cut-off frequency variations of power diodes under different gamma irradiation doses. The samples were irradiated at a gamma facility, {sup 60}Co-Gammacell 220 (dose rate of 2.31 kGy/h), in the Radiation Technology Center (CTR) at IPEN/CNEN-SP. The temperature during exposure was typically 25 deg C. The values of direct voltage and the temporal response of the devices were studied for an accumulated dose of 1350 kGy. The results have shown an improvement of the reverse recovery behavior of this type of diode, as well as a 10% decrease in its direct voltage. (author)

  8. Effects of Pre-exposure Mouse Pituitary with Low-dose 60Co γ-ray on Growth Hormone (GH) and Body Mass Induced by Subsequent High-dose Irradiation

    Institute of Scientific and Technical Information of China (English)

    ZhangHong; LiWenjian; JingXiaodong; LiuBing; MinFengling; ZhouQingming; XieYi

    2003-01-01

    The pituitary of the B6C3F1 hybrid strain mice were irradiated with 0.05 Gy of 60Co γ-ray as the pre-exposure dose (D1), and were then irradiated with 2 Gy of 60Co γ-ray as challenging irradiation dose (D2) at 4h after per-exposure. Body weight and serum growth hormone (GH) were measured at 35th day after irradiation. The results showed that irradiation of mouse testes with 2 Gy of 60Co γ-ray significantly diminished mousebody weight and level of serum GH (Table). Pre-exposure with a low-dose (0.05 Gy) of 60Co γ-ray significantly alleviated reductions of mouse body weight and level of serum GH induced by subsequent a high-dose (2 Gy) irradiation (Table). The data suggested that low-dose ionizing irradiation can induce adaptive responses to the harmful effects of pituitary by subsequent high-dose exposure.

  9. Gamma irradiation treatment of cereal grains for chick diets

    International Nuclear Information System (INIS)

    Wheat (W), triticale (T), hulled barley (HB), hull-less barley (HLB), hulled oats (HO), and hull-less oats (HLO) were gamma irradiated (60Co) at 0, 3, 6 and 9 Mrad to study the effect of irradiation on the nutritional value of cereal grains for chicks. A significant curvilinear relationship between radiation dose and 3-wk body weight of chicks fed irradiated cereals was noted for T, HB, HLB, HO and HLO. Chicks fed W or T showed no effect or lower body weight, respectively, while body weights of chicks fed barley or oat samples were higher with irradiation. The improvement tended to be maximal at the 6 Mrad level. Irradiation significantly improved the gain-to-feed ratio for chicks fed either HO or HLO. Apparent fat retention and tibia ash were higher in chicks fed irradiated HLO than in those fed untreated HLO. In a second experiment chick body weight, apparent amino acid and fat retention, tibia ash, and gain-to-feed ratios were lower in chicks fed autoclaved (121 degrees C for 20 min) barley than in those fed untreated barley. Irradiation (6 Mrad) subsequent to autoclaving barley samples eliminated these effects. Irradiation appears to benefit cereals containing soluble or mucilagenous fiber types as typified by beta-glucan of barley and oats. These fibers appear prone to irradiation-induced depolymerization, as suggested by increased beta-glucan solubility and reduced extract viscosity for irradiated barley and oat samples

  10. Low dose gamma irradiation has no effect on the functionality of fish proteins

    International Nuclear Information System (INIS)

    Indian mackerel in ice was gamma irradiated to 1.5 and 3.0 kGy using 60Co source. Washed meat from the treated fish was homogenised in cold water and the viscosity and solubility characteristics of the homogenates were measured with respect to protein concentration, pH and temperature. Irradiation did not cause significant alterations in viscosity and solubility characteristics of the proteins. (author)

  11. Polymerization of vinyl acetate in bulk and emulsion by gamma irradiation

    Science.gov (United States)

    Mesquita, Andrea C.; Mori, Manoel N.; Andrade e Silva, Leonardo G.

    2004-09-01

    The vinyl acetate polymerization to produce poly(vinyl acetate) was carried out in bulk and emulsion using a 60Co gamma irradiator Gammacell-220 type. The irradiation was carried out in a dose rate of 5.25 and 5.30 kGy/h, respectively. The polymers obtained were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and gel permeation chromatography (GPC). Tests of density, hardness and Vicat softening temperature were carried out.

  12. Gamma irradiation of fruits

    International Nuclear Information System (INIS)

    At a Joint FAO/IAEA/WHO Expert Committee on Food Irradiation (JECFI) meeting held in 1976, recommendations were made to rationalize the unnecessarily elaborate wholesomeness evaluation procedures for irradiated foodstuffs. Irradiation at the commercially recommended doses did not adversely affect the constituents of mangoes, papayas, litchis and strawberries at the edible-ripe stage. These favourable radiation-chemical results justified the development of a theoretical model mango which could be used for extrapolation of wholesomeness data from an individual fruit species to all others within the same diet class. Several mathematical models of varying orders of sophistication were evolved. In all of them, it was assumed that the radiant energy entering the system reacted solely with water. The extent of the reaction of the other components of the model fruit with the primary water radicals was then determined. No matter which mathematical treatment was employed, it was concluded that the only components which would undergo significant modification would be the sugars. In order to extrapolate these data from the mango to other fruits, mathematical models of three fruits containing less sugar than the mango, viz. the strawberry, tomato and lemon, were compiled. With these models, the conclusion was reached that the theoretical degradation spectra of these fruits were qualitatively similar to the degradation pattern of the model mango. Theory was again substantiated by the practical demonstration of the protective effect of the sugars in the tomato and lemon. The decrease in radiation damage was enhanced by the mutual protection of the components of the whole synthetic fruits with ultimate protection being afforded by the biological systems of the real fruits

  13. Properties of Pulsed Photostimulated Luminescence and Thermoluminescence for Detection of Gamma-Irradiated Teas during Storage

    International Nuclear Information System (INIS)

    Green, black and oolong teas were irradiated by @@€@@60Co-gamma rays (0~10 kGy) and were investigated for detection of irradiation treatment using pulsed photostimulated luminescence (PPSL) and thermoluminescence (TL) during storage. Teas irradiated at 2.5 kGy or more showed a photon count of greater than 5000 counts/60 sec while the non-irradiated yielded only 650~1000 count/60 sec. Correlation coefficients between irradiation dose and photon counts/60 sec were 0.8951, 0.7934 and 0.9007 for green, black and oolong teas, respectively

  14. TEST RESULTS FROM GAMMA IRRADIATION OF ALUMINUM OXYHYDROXIDES

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, D.; Westbrook, M.; Sindelar, R.

    2012-02-01

    Hydrated metal oxides or oxyhydroxides boehmite and gibbsite that can form on spent aluminum-clad nuclear fuel assemblies during in-core and post-discharge wet storage were exposed as granular powders to gamma irradiation in a {sup 60}Co irradiator in closed laboratory test vessels with air and with argon as separate cover gases. The results show that boehmite readily evolves hydrogen with exposure up to a dose of 1.8 x 10{sup 8} rad, the maximum tested, in both a full-dried and moist condition of the powder, whereas only a very small measurable quantity of hydrogen was generated from the granular powder of gibbsite. Specific information on the test setup, sample characteristics, sample preparation, irradiation, and gas analysis are described.

  15. Selective expression of mutated p53 in human cells immortalized with either 4-nitroquinoline 1-oxide or 60Co gamma rays

    International Nuclear Information System (INIS)

    Many studies on in vitro transformation of human cells indicate that the cells must be immortalized before they can be neoplastically transformed, indicating that immortalization is a critical step in multistep neoplastic transformation of human cells. We immortalized three human cell lines by repeated treatment with either 60Co gamma rays or a chemical carcinogen, 4-nitroquinoline 1-oxide, and found that all three immortalized cell lines have mutations in the tumor suppressor gene, p53. Direct sequencing of the reverse-transcribed mRNA and immunoprecipitation of p53 protein revealed that mutant p53 is selectively expressed in all the immortalized cell lines, whereas the genomic fragments of the immortalized cells contain wild-type and mutated p53 alleles. Although the mutated p53 is selectively expressed in the immortalized cells, expression of the wild-type p53 was induced by treatment of the cells with a hypomethylating reagent, 5-azacytidine, indicating that the wild-type p53 allele might be inactivated by hypermethylation of DNA. Actually, the entire genomic locus including the promoter region of p53 is hypermethylated in all the immortalized cell lines. Expression and phosphorylation of Rb was normal in these three cell lines. Thus, inactivation of both wild type p53 alleles and selective expression of mutated p53 seem to be key factors in the immortalization of human fibroblasts. (author)

  16. Food irradiation: Gamma processing facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kunstadt, P. [MDS Nordion International, 447 March Road. Kanata, Ontario, K2K148 (Canada)

    1997-12-31

    The number of products being radiation processed is constantly increasing and today include such diverse items as medical disposable, fruits and vegetables, bulk spices, meats, sea foods and waste effluents. Not only do the products differ but also many products, even those within the same groupings, require different minimum and maximum radiation doses. These variations create many different requirements in the irradiator design. The design of Cobalt-60 radiation processing facilities is well established for a number of commercial applications. Installations in over 40 countries, with some in operation since the early 1960s, are testimony to the fact that irradiator design, manufacture, installation and operation is a well established technology. However, in order to design gamma irradiators for the preservation of foods one must recognize those parameters typical to the food irradiation process as well as those systems and methods already well established in the food industry. This paper discusses the basic design concepts for gamma food irradiators. They are most efficient when designed to handle a limited product density range at an established dose. Safety of Cobalt-60 transport, safe facility operation principles and the effect of various processing parameters on economics, will also be discussed. (Author)

  17. Food irradiation: Gamma processing facilities

    International Nuclear Information System (INIS)

    The number of products being radiation processed is constantly increasing and today include such diverse items as medical disposable, fruits and vegetables, bulk spices, meats, sea foods and waste effluents. Not only do the products differ but also many products, even those within the same groupings, require different minimum and maximum radiation doses. These variations create many different requirements in the irradiator design. The design of Cobalt-60 radiation processing facilities is well established for a number of commercial applications. Installations in over 40 countries, with some in operation since the early 1960s, are testimony to the fact that irradiator design, manufacture, installation and operation is a well established technology. However, in order to design gamma irradiators for the preservation of foods one must recognize those parameters typical to the food irradiation process as well as those systems and methods already well established in the food industry. This paper discusses the basic design concepts for gamma food irradiators. They are most efficient when designed to handle a limited product density range at an established dose. Safety of Cobalt-60 transport, safe facility operation principles and the effect of various processing parameters on economics, will also be discussed. (Author)

  18. Effects of {sup 60}Co gamma radiation on toxicity and hemorrhagic, myonecrotic, and edema-forming activities of Cerastes cerastes venom

    Energy Technology Data Exchange (ETDEWEB)

    Abib, H. [Univ. des Sciences et de la Technologie, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Houari Boumedienne, Bab Ezzouar (Algeria); Laraba-Djebari, F. [Inst. Pasteur d' Algerie, Lab. de Recherche et de Developpement sur les Venins, Alger (Algeria)]. E-mail: flaraba@ibnsina.ands.dz

    2003-12-01

    Antisera are used as effective antidotes against the local effects of snake bites. To improve antisera production and extend the life of surrogates used to produce antibodies, the chronic effects of venom toxicity must be reduced. The present study evaluated the effectiveness of gamma irradiation to reduce the local effects associated with viperid snake bites by evaluating in NMRI mice the toxicity and edematic, hemorrhagic, and myonecrotic activities of native and irradiated Cerastes cerastes venoms. These results indicated that the toxicity of irradiated venoms (1 and 2 kGy) decreased as compared with that of native venom. The edematic and hemorrhagic activities were also reduced in the detoxified samples, particularly with the 2-kGy radiation dose. Furthermore, the creatine phosphokinase (CPK) activity was significantly increased in the serum and decreased in the myocardium after envenomation with native venom, but no significant enzymatic changes were observed in mice envenomated with irradiated venom. Histopathologic evaluation showed that native venom caused severe degenerative changes in the myocardium. In the case of 2-kGy-irradiated venom, no tissue alterations were observed. These results indicate that irradiation of venom with a 2-kGy dose may offer an effective method for reducing the chronic toxic effects of venom in immunized animals. (author)

  19. Thermoluminescence of Simulated Interstellar Matter after Gamma-ray Irradiation

    CERN Document Server

    Koike, K; Koike, C; Okada, M; Chihara, H

    2002-01-01

    Interstellar matter is known to be strongly irradiated by radiation and several types of cosmic ray particles. Simulated interstellar matter, such as forsterite $\\rm Mg_{2}SiO_{4}$, enstatite $\\rm MgSiO_{3}$ and magnesite $\\rm MgCO_{3}$ has been irradiated with the $\\rm ^{60}Co$ gamma-rays in liquid nitrogen, and also irradiated with fast neutrons at 10 K and 70 K by making use of the low-temperature irradiation facility of Kyoto University Reactor (KUR-LTL. Maximum fast neutron dose is $10^{17}n_f{\\rm /cm^{2}}$). After irradiation, samples are stored in liquid nitrogen for several months to allow the decay of induced radioactivity. We measured the luminescence spectra of the gamma ray irradiated samples during warming to 370K using a spectrophotometer. For the forsterite and magnesite, the spectra exhibit a rather intense peak at about 645 -- 655 nm and 660 nm respectively, whereas luminescence scarcely appeared in olivine sample. The spectra of forsterite is very similar to the ERE of the Red Rectangle.

  20. 大剂量rhG-CSF早期单次给药对60Coγ射线照射小鼠的治疗作用%Therapeutic effects of early administration of a single high dose of rhG-CSF on mice irradiated by 60Coγ rays

    Institute of Scientific and Technical Information of China (English)

    韩阿如娜; 余祖胤; 柳晓兰; 从玉文

    2011-01-01

    Objective To observe the therapeutic effects of early administration with a single high dose of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on mice irradiated with 60Co γ rays, and provide a reference for the treatment of acute radiation syndrome (ARS) by using cytokines. Methods Male C57 mice underwent a total body irradiation of 8. Ogy 60Co y ray, and they were treated with rhG-CSF, at 0.5h and 24h, subcutaneously in a dose of 2, 1 and 0. 5mg/kg, respectively. The 30-day survival rate and mean survival time were observed in the lethal irradiated mice. The peripheral blood cell counts and bone marrow nucleated cell counts were evaluated in the sublethally irradiated mice. Results Early administration of a high dose of rhG-CSF significantly increased 30-day survival rate and prolonged mean survival time of mice with lethal irradiation dose. A single injection of rhG-CSF (lmg/kg) at 0. 5h after irradiation was an optimal administration schedule. In addition, early administration with a single high dose of rhG-CSF improved the recovery of bone marrow nucleated cell counts and peripheral blood counts, including white blood cell (WBC), red blood cell (RBC) and platelet in mice exposed to 6. Ogy irradiation. Conclusion Early administration of a single high dose rhG-CSF may have a favorable therapeutic effect on mice irradiated with 60Co y ray.%目的 观察大剂量rhG-CSF早期单次给药对60Coγ射线照射小鼠的治疗作用,为细胞因子治疗急性放射病提供实验依据.方法 雄性C57小鼠,经8.0Gy 60Co γ射线全身照射后于0.5、24h各皮下注射一次不同剂量rhG-CSF(2、1mg/kg和0.5mg/kg),观察致死剂量照射小鼠的30d存活率及平均生存时间.小鼠经6.0Gy 60Co γ射线全身照射后,通过不同给药方案及不同剂量rhG-CSF早期干预,观察亚致死剂量照射小鼠的外周血象和骨髓有核细胞数的变化.结果 大剂量rhG-CSF早期干预明显提高致死剂量照射小鼠的30d存

  1. Variation in electrical properties of gamma irradiated cadmium selenate nanowires

    Science.gov (United States)

    Chauhan, R. P.; Rana, Pallavi; Narula, Chetna; Panchal, Suresh; Choudhary, Ritika

    2016-07-01

    Preparation of low-dimensional materials attracts more and more interest in the last few years, mainly due to the wide field of potential commercial applications ranging from life sciences, medicine and biotechnology to communication and electronics. One-dimensional systems are the smallest dimension structures that can be used for efficient transport of electrons and thus expected to be critical to the function and integration of nanoscale devices. Nanowires with well controlled morphology and extremely high aspect ratio can be obtained by replicating a nanoporous polymer ion-track membrane with cylindrical pores of controlled dimensions. With this technique, materials can be deposited within the pores of the membrane by electrochemical reduction of the desired ion. In the present study, cadmium selenate nanowires were synthesized potentiostatically via template method. These synthesized nanowires were then exposed to gamma rays by using a 60Co source at the Inter University Accelerator Centre, New Delhi, India. Structural, morphological, electrical and elemental characterizations were made in order to analyze the effect of gamma irradiation on the synthesized nanowires. I-V measurements of cadmium selenate nanowires, before and after irradiation were made with the help of Keithley 2400 source meter and Ecopia probe station. A significant change in the electrical conductivity of cadmium selenate nanowires was found after gamma irradiation. The crystallography of the synthesized nanowires was also studied using a Rigaku X-ray diffractrometer equipped with Cu-Kα radiation. XRD patterns of irradiated samples showed no variation in the peak positions or phase change.

  2. Differential radio-sensitivities of human chromosomes 1 and 2 in one donor in interphase- and metaphase-spreads after 60Co γ-irradiation

    International Nuclear Information System (INIS)

    Radiation-induced chromosome aberrations lead to a plethora of detrimental effects at cellular level. Chromosome aberrations provide broad spectrum of information ranging from probability of malignant transformation to assessment of absorbed dose. Studies mapping differences in radiation sensitivities between human chromosomes are seldom undertaken. Consequently, health risk assessment based on radio-sensitivities of individual chromosomes may be erroneous. Our efforts in this article, attempt to demonstrate differences in radio-sensitivities of human chromosome-1 and/or -2, both in interphase and metaphase spreads. Upon blood collection, dosimetry and irradiation were performed. Lymphocytes were isolated after whole-blood irradiation with 60Co γ-rays in the dose range of 0–5 Gy for both interphase, and metaphase aberration studies. Induction of premature chromosome condensation in interphase cells was accomplished using a phosphatase inhibitor, calyculin-A. Metaphase spreads were harvested from short-term peripheral blood lymphocyte cultures following colcemid arrest and using an automated metaphase harvester and spreader. Aberration analysis in both interphase and metaphase spreads were done using FISH. In interphase, aberrant cell and aberration frequency involving chromosome 1 and/or 2 increased linearly with radiation dose. In metaphase, aberrations increased in a linear-quadratic manner with dose. Our studies ascertain that chromosome-2 is more radio-sensitive than chromosome-1 in both interphase and metaphase stages, albeit the DNA content of chromosome-2 is lesser than chromosome-1 by almost 10 million base pairs. Differences in radio-sensitivities of chromosomes have implications in genetic damage, chromosome organization, and chromosome function. Designing research experiments based on our vital findings may bring benefit to radiation-induced risk assessment, therapeutics and development of chromosome specific biomarkers

  3. Gamma Irradiation does not Cause Carcinogenesis of Irradiated Herbs

    International Nuclear Information System (INIS)

    Full text: Microbial contamination of medicinal herbs can be effectively reduced by gamma irradiation. Since irradiation may cause carcinogenicity of the irradiated herbs, the objective of this research is to study the effect of gamma irradiation (10 and 25 kGy) from cobalt-60 on carcinogenicity. The herbs studied were Pueraria candollei Grah., Curcuma longa Linn. Zingiber montanum, Senna alexandrina P. Miller, Eurycoma Longifolia Jack, Gymnostema pentaphylum Makino, Ginkgo biloba, Houttuynia cordata T., Andrographis paniculata, Thunbergia laurifolia L., Garcinia atroviridis G., and Cinnamomum verum J.S.Presl. The results showed that gamma irradiation at the dose of 10 and 25 kGy did not cause carcinogenicity of the irradiated herbs

  4. Inactivation effect of 60Co gamma ray on cysticerci of Taenia solium in pork%60Coγ射线对猪肉中囊尾蚴的辐照杀灭效应

    Institute of Scientific and Technical Information of China (English)

    钟凯; 高翔; 计融

    2011-01-01

    Objective revealing the relationship between irradiation dose and inactivation ratio for eysticerei of Taenia solium in pork, determining the minimal dose for totally killing cysticerci and providing scientific evidence for setting up relevant hygienic standards of radiation. Methods After Taenia solium infected pork being treated with different irradiation doses; cysticerci were separated and incubated in fresh swine bile. The adjusted inactivation ratio was calculated according to the survival rate. Results There was a linear correlation between irradiation dose and adjusted inactivation ratio, the D10 value was about 3.8 kGy, and a totally killing could be achieved by 4.5 kGy irradiation. Conclusion Irradiation at a dose of 4.5 kGy could be applied as the maximum dose to inactivate cysticerci of Taenia solium in pork processing.%目的 揭示猪肉中囊尾蚴灭活率与辐照剂量的相关关系及最小杀灭剂量,为制定相应辐照卫生规范提供科学依据.方法 以不同剂量Co γ射线处理感染囊尾蚴的猪肉,并用新鲜猪胆汁孵化剥离出的囊尾蚴,根据成活率计算校正灭活率.结果 辐照剂量与校正灭活率具有线性相关,D值约为3.8 kGy,4.5 kGy可完全杀灭囊尾蚴.结论 4.5 kGy γ射线对猪肉中囊尾蚴有很好的杀灭效果.

  5. Evaluation of the radio modifier effect of propolis on chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60-CO

    International Nuclear Information System (INIS)

    In the last decades, it has been given a great interest to investigations concerning natural, effective, nontoxic compounds with radioprotective potential together with the increasing utilization of different types of ionizing radiation for various applications. Among them propolis, a resinous compound produced by honeybees (Apis mellifera), has been considered quite promising, since it presents several advantageous biological characteristics, i. e., anti-inflammatory, antimicrobial, anticarcinogenic, antioxidant and also free radical scavenging action. The purpose of the present study was to evaluate the effect of Brazilian propolis, collected in the State of Rio Grande do Sul, on Chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60Co γ radiation. For this purpose, three interlinked parameters were analyzed: micronucleus induction, cell viability and clonogenic death. The choice of these parameters was justified by their biological significance, in addition to the fact that they are readily observable and measurable in irradiated cells. The cytogenetic data obtained showed a radioprotective effect of propolis (5-100 μg/ml) in the induction of DNA damage for both cell lines, irradiated with doses of 1 - 4 Gy. The cytotoxicity assay, however, showed a prominent antiproliferative effect of propolis (50 - 400μ/ml) in PC3 cells irradiated with 5 Gγ. The survival curves obtained were adequately fitted by a linear-quadratic model, where the α coefficient was higher in CHO-K1 cells. Concerning the clonogenic capacity, PC3 cells were more radiosensitive than CHO-K1 cells at the higher doses of the survival curve. Propolis at the concentrations of 30 - 100 μg/ml, did not influence the clonogenic potential of PC3 cells, since the survival curves, associated or not with propolis, were found similar, although the combined treatment in CHO-K1 cells exhibited a stimulating proliferative effect. The data obtained in vitro showed a

  6. Effect of sodium alginate coating and 60Coirradiation treatment on fresh-keeping of golden silk jujube%海藻酸钠涂膜及60Co-γ辐照处理对小枣的保鲜作用

    Institute of Scientific and Technical Information of China (English)

    杨伟; 徐莹; 樊燕; 汪东风; 孙寿魁

    2012-01-01

    Using golden silk jujube at full-red storage as materials,the effects of different preservation treatments(60Coirradiation,coating with sodium alginate,and 60Co-γ irradiation+coating with sodium alginate,respectively) on the post-harvest fruit quality during cold storage were investigated,and the weight loss rate,total sugar content,reducing sugar content,VC content,and ratio of sugar to acid were determined.The results indicated that 60Coirradiation,coating with sodium alginate and 60Co-γ irradiation+coating with sodium alginate all had an obvious fresh-keeping effect.The result showed that the three treatments reduced water loss,delayed the decrease of VC and titratable acid content,and the increase of sugar to acid ratio,and 60Co-γ irradiation+coating with sodium alginate maintained a relatively high content of total sugar and reducing sugar.Especially,the preservative effect of the 60Co-γ irradiation+coating with sodium alginate treatment was obviously superior to the control group,60Coirradiation or coating with sodium alginate alone,which could obviously improve the quality of post-harvest cold storage of golden silk jujube.%以全红期的山东省乐陵小枣为实验材料,分别进行60Co-γ辐照处理、海藻酸钠涂膜处理及二者结合处理后,与对照组同时于(2±0.5)℃冷库贮藏,并对低温贮藏过程中枣的失重率、总糖、还原糖、VC、可滴定酸含量及糖酸比的变化进行测定。结果表明:涂膜、辐照、涂膜+辐照处理均能有效减少水分散失,延缓VC和可滴定酸的下降,抑制糖酸比的上升,涂膜+辐照处理能保持较高的总糖、还原糖含量。其中,60Co-γ辐照+海藻酸钠涂膜处理于(2±0.5)℃冷库贮藏保鲜效果显著优于其他实验处理组,有助于提高乐陵小枣采后的低温贮藏品质。

  7. Chemical constituents of Panax ginseng exposed to. gamma. irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Joongho; Belanger, J.M.R.; Sigouin, M.; Lanthier, J.; Willemot, C.; Pare, J.R.J. (Agriculture Canada, Saint-Hyacinthe, Quebec (Canada))

    1990-03-01

    Chemical constituents were monitored to assess the biochemical and nutritional safety of Panax ginseng powders that were irradiated at doses of 1-10 kGy. Quantitative analysis has shown that the main effective components - saponins - are not altered by {sup 60}Co {gamma} irradiation. Ginsenoside-Rg{sub 1} was not affected by the treatment. Negligible changes were observed in the free carbohydrate contents. Doses of more than 5 kGy caused significant decreases in sulfur-containing amino acids and in tyrosine. At doses of 10 kGy, free amino acids, such as proline and lysine, showed an appreciable increase. The composition in minerals was not altered irrespective of the applied doses.

  8. Gamma-ray Irradiation Induces Useful Morphological Variation in Bermudagrass

    Directory of Open Access Journals (Sweden)

    Songul SEVER MUTLU

    2015-12-01

    Full Text Available Bermudagrass, Cynodon dactylon (L. Pers. is a widely used warm-season turfgrass species in warmer regions of the world. Gammairradiation has been used to generate useful variations in turfgrass breeding for various morphological traits. The objective of the present study was to measure and determine variations in morphology and turfgrass characteristics of a native drought resistant bermudagrass germplasm irradiated with 70, 90 or 110 Gy using a 60Co source. The stolons containing a single node were irradiated and immediately planted for regeneration in a greenhouse at the Akdeniz University, Antalya, Turkey. Selected mutants regenerated from the irradiated stolons were clonally propagated and transplanted into plastic pots for further observations of turfgrass characteristics.  Survival rates of stolons exposed to 70, 90 and 110 Gy were 76%, 43% and 17% respectively, 6 weeks after treatment. Dosages of 85 and 57 Gy were determined as LD50 and LD20 for the cuttings, respectively. The linear reduction of survival rate with increasing gamma-rays was highly correlated (r2=0.99. A total of four mutant lines (0.3 % of the irradiated plants showed a distinct dwarfed growth habit. Three of these lines were originated from 70 Gy and one from 110 Gy. These mutant lines exhibited more dwarf growth habit, higher shoot density, finer leaf texture than parental genotype. Mutant lines developed in this study can be used for the development of improved bermudagrass cultivars for landscaping and sports turf.

  9. Effect of gamma irradiation on nutrient digestibility in SPF mini-pig

    Science.gov (United States)

    Lee, Jun-Yeob; Cho, Sung-Back; Kim, Yoo-Yong; Ohh, Sang-Jip

    2011-01-01

    This study was carried out to evaluate the effect of gamma irradiation on nutrient digestibility of either soy-based or milk-based diet for specific pathogen-free (SPF) mini-pigs. Gamma irradiation of the diets was done at dosage of 10 kGy with 60Co whereas autoclaving was executed at 121 °C for 20 min. Apparent crude protein digestibilities of gamma irradiated diets were higher ( pdiets regardless of diet type. Digestibilities of dry matter, gross energy and total carbohydrate in the irradiated diet were higher than those of the autoclaved diet. From the results of nutrient digestibility of mini-pig diets in this study, 10 kGy gamma radiation was suggested as a convenient diet radicidation method that can minimize the decrease in nutrient digestibility on feeding to SPF mini-pigs.

  10. Effect of gamma irradiation on nutrient digestibility in SPF mini-pig

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jun-Yeob [College of Animal Life Sciences , Kangwon National University, 192-1 Kangwon Avenue 1, Chuncheon, Gangwon-do 200-701 (Korea, Republic of); Cho, Sung-Back [Swine Science Division, National Institute of Animal Science, Cheonan, Chungcheongnam-do 330-801 (Korea, Republic of); Kim, Yoo-Yong [College of Agriculture and Life Science, Seoul National University, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Ohh, Sang-Jip, E-mail: sjohh@kangwon.ac.k [College of Animal Life Sciences , Kangwon National University, 192-1 Kangwon Avenue 1, Chuncheon, Gangwon-do 200-701 (Korea, Republic of)

    2011-01-15

    This study was carried out to evaluate the effect of gamma irradiation on nutrient digestibility of either soy-based or milk-based diet for specific pathogen-free (SPF) mini-pigs. Gamma irradiation of the diets was done at dosage of 10 kGy with {sup 60}Co whereas autoclaving was executed at 121 {sup o}C for 20 min. Apparent crude protein digestibilities of gamma irradiated diets were higher (p<0.05) than those of autoclaved diets regardless of diet type. Digestibilities of dry matter, gross energy and total carbohydrate in the irradiated diet were higher than those of the autoclaved diet. From the results of nutrient digestibility of mini-pig diets in this study, 10 kGy gamma radiation was suggested as a convenient diet radicidation method that can minimize the decrease in nutrient digestibility on feeding to SPF mini-pigs.

  11. A commercial gamma-ray irradiation plant in Japan

    International Nuclear Information System (INIS)

    In 1973, a commercial gamma-ray irradiation plant was constructed in Takasaki, about 100 km north of Tokyo. The plant has been used for both production of irradiated commercial products and irradiation services. The irradiation services are being made available for sterilization of both medical appliances such as disposable medical syringes, catheters, surgical sutures, and sterilization of feed stuffs for animals. Treatment of plastic materials and colouring of both crystals and glass wares are also undertaken. This facility can accommodate 600 kCi of 60Co and has a monthly treating capacity of 12,000 packages ( a standard carton of 340 mm x 400 mm x 500 mm) at an irradiation dose of 1 Mrad/hr. A receiving port for packages is on the second floor and the outlet of the irradiated packages on the first floor, with three lines of connecting loop conveyors between them, and the irradiation compartment in the center section. The space arrangement of the facility is well designed and gravity can be utilized for the transportation of the packages. Polymer impregnated coral is put on the market for ornamental building material on an order contract basis. (author)

  12. Effect of 60Co γ-ray Irradiation on Growth Characteristics of Chamaecrista%60Co-γ射线辐照处理对决明若干生长特性的影响

    Institute of Scientific and Technical Information of China (English)

    翁伯琦; 徐国忠; 郑向丽; 应朝阳; 黄毅斌

    2005-01-01

    利用60℃o-γ射线(辐照剂量为300 Gy,剂量率为4.687 5 Gy/min)辐照豆科决明属5个牧草品种的种子,通过盆栽收集各个品种的M1代种子,然后进行M2代试验与观察.结果表明,辐照后5个决明M2代的种子出苗率、植株的茎长、叶宽均无显著差异;34721号决明植株冠高有显著增长、2219号决明茎径有显著增长、86134号决明分枝数有极显著增长,92985号决明分枝数则有显著降低、86134号决明叶数和地上部植株干重有显著增长、2219号决明叶长增长显著,其余参试品种则无显著差异.植株的营养成分测定表明:仅2219号决明K含量呈显著下降、其他品种的N,P,K含量则无显著差异;2219不仅氨基酸总量呈显著下降、而且17种氨基酸都表现为不同程度的下降,86134氨基酸总量有显著增长、同时17种氨基酸都表现为不同程度的增长,而其余3个参试品种都无显著差异.经60Co-γ射线辐照处理后的34721,86134,92985的酯酶同工酶谱与相应的对照有明显差别.生长观察结果表明,参试的5个决明品种M2代植株生长的现蕾期、初花期、盛花期、初荚期、盛荚期、成熟期表现为双向性,既有提早,也有推迟.

  13. [Changes in the collagen amino acid composition of calf skin after gamma-irradiation in an aqueous solution].

    Science.gov (United States)

    Duzhenkova, N A; Savich, A V

    1983-01-01

    A study was made of the amino acid composition of calf skin collagen after gamma-irradiation (60Co) of 2.5 X 10(-6) M aerated aqueous protein solution within the dose range from 30 to 2000 Gy. The radiosensitivity of amino acid residues was compared. PMID:6657935

  14. Dose-dependence of the chromosome aberration yield in a human lymphocyte culture after. gamma. -irradiation with high doses

    Energy Technology Data Exchange (ETDEWEB)

    Sevan' kaev, A.V. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

    A study was made of the yield of chromosome aberrations in a human lymphocyte culture at the G/sub 0/ stage after /sup 60/Co-..gamma..-irradiation with doses of 5-12 Gy. It was shown that a linear-quadratic dependence of the aberration frequency observed with median doses became purely linear at high doses.

  15. Increasing genetic variability in black oats using gamma irradiation.

    Science.gov (United States)

    Silveira, G; Moliterno, E; Ribeiro, G; Costa, P M A; Woyann, L G; Tessmann, E W; Oliveira, A C; Cruz, C D

    2014-01-01

    The black oat (Avena strigosa Schreb) is commonly used for forage, soil cover, and green manure. Despite its importance, little improvement has been made to this species, leading to high levels of genotypic disuniformity within commercial cultivars. The objective of this study was to evaluate the efficiency of different doses of gamma rays [(60)Co] applied to black oat seeds on the increase of genetic variability of agronomic traits. We applied doses of 0, 10, 50, 100, and 200 Gy to the genotype ALPHA 94087 through exposure to [(60)Co]. Two experiments were conducted in the winter of 2008. The first aimed to test forage trait measurements such as plant height, dry matter yield, number of surviving tillers, and seedling stand. The second test assessed seed traits, such as yield and dormancy levels. Gamma irradiation seems not to increase seed yield in black oats, but it was effective in generating variability for the other traits. Tiller number and plant height are important selection traits to increase dry matter yield. Selection in advanced generations of mutant populations can increase the probability of identifying superior genotypes.

  16. Effect of gamma radiation from {sup 60}C in conservation and quality of pepper fresh and pulp; Efeito da radiacao gama do {sup 60}Co na conservacao e qualidade de pimenta in natura e em polpa

    Energy Technology Data Exchange (ETDEWEB)

    Milagres, Regina Celia Rodrigues de Miranda

    2014-07-01

    Capsicum peppers are among the most used and most valued seasoning spices in the world. They are highly susceptible to post harvest decay, therefore the use of irradiation may contribute to conservation of this fruit which has significant nutritional, economic and social value. Were evaluated the effects of gamma radiation of {sup 60}Co in increasing the shelf-life and preservation of quality of pepper 'Dedo-de-moca' (Capsicum baccatum var. Pendulum) fresh and pulp associated or not with another conservation methods. Gamma radiation doses were investigated of 0,25; 0,50; 0,75; 1,00; 1,25; 1,50; 2,00 e 3,00 kGy in fresh fruit and 1,50; 2,00; 3,00; 4,50 e 6,00 kGy in pepper pulp. The use of laboratory pasteurization (85°C/3min), the addition of citric acid (5%) and 5% NaCl were also investigated in the pepper pulp. The samples were stored at 5 °C and or 25 °C. Were performed analysis: visual (disease incidence, turgidity and color); bioactive compounds (carotenoids, capsaicinoids, antioxidant capacity and phenolic compounds); physicochemical (Weight loss, firmness, soluble solids (SS), pH, titratable acidity (TA), ratio, color and moisture); respiratory rate and ethylene production; proximate composition (moisture, soluble and insoluble fiber, ash, protein, ether extract, total and available carbohydrate); microbiological contamination (mesophilic aerobic microorganisms, coliforms at 45 °C, Salmonella spp. and yeasts and molds) and sensory (acceptance test, difference test and paired preference). Radiation doses between 0.25 and 3.00 kGy were not effective to increase shelf-life and maintain fresh pepper quality during storage. There was increased intensity of red color, of incidence of disease, decreased turgidity and changes in physical, chemical and nutritional parameters. In pulp, the doses of gamma radiation of 4.50 and 6.00 kGy and the addition of 5% NaCl no changing sensory attributes, physical-chemical and bioactive compounds. Only the

  17. 6Co γ射线诱发小鼠DNA甲基化改变%DNA methylation changes induced by 60 Co γ-ray irradiation

    Institute of Scientific and Technical Information of China (English)

    黄铖铖; 孙秀锦; 胡明江; 程跃进; 古桂雄; 崔凤梅

    2011-01-01

    Objective To study the change and significance of DNA methylation pattern and DNA methyltransferase (DNMT1) protein in 60Co γ-ray irradiated mice tissues. Methods Twelve SPF C57BL/6J mice were randomly divided in-tocontrol group and radiation group. The radiation group were exposed to 4Gy-single whole body radiation. All mice were sacrificed 3 days after the radiation. The total number of peripheral white blood cells and the frequencies of micronucleated polychromatic erythocytes(fMNPCE) were measured. Methylated DNA immunoprecipitation-chip(MeDIP-chip) was adopted to investigate the differentially expressed CpG islands methylation profiles in mouse liver genome promoter. The immunohisto-chemical(SP method) and western blot method were used to check the expression of DNMT1 protein in tissues. Results Compared with the control group,the promoter methylation profiles of irradiated mice changed obviously, with 1300 genes methylated and 660 genes demethylated. With the improvement of the screening criteria,the obviously methylated genes were Trim71,Sema3f, Pcdh8,Sox4,1110034A24Rik, Limkl, Nefl, and Xprl and the demethylated genes were Sfrsl8,Drl, Ankrd42,Nael ,Sfil ,Accnl ,Srd5al ,Nsun2,Eifla,and Dusp5. Except in the lung,the expression of DNMT1 protein in liver, kidney, testicle, and brain tissues were all increased (P < 0.05). Conclusion There are methylation changes of gene promoter in ionizing radiation injury and the increased expression of DNMT1 may be the reason of gene promoter methylation.%目的 探讨基因组启动子甲基化谱及DNA甲基化酶1(DNMT1)表达量在60Co-γ射线照射小鼠各组织的变化及其意义.方法SPF级C57BL/6J雄性小鼠12只随机分为对照组和照射组,照射组小鼠接受4Gy60 Co-y射线单次全身照射后,均眼球摘除取血后处死,收集各脏器组织,进行外周血白细胞计数和骨髓嗜多染红细胞微核计数,应用甲基化DNA免疫沉淀-芯片(MeDIP-chip)杂交技术对y射线

  18. Crosslinking of metallocenic α-olefin propylene copolymers by vacuum gamma irradiation

    Science.gov (United States)

    Satti, A. J.; Andreucetti, N. A.; Quijada, R.; Vallés, E. M.

    2012-12-01

    Metallocenic polypropylene and copolymers with 3.7, and 9.2 mol% of hexene and 3.0 mol% of octadecene comonomer content were synthesized without the presence of additives and irradiated with 60Co gamma radiation under vacuum at room temperature. Size Exclusion Cromatography and gel extraction data showed that scission reactions predominate over crosslinking in the homopolymer and that there is a dose from where crosslinking started to increase considerably, in the irradiated copolymers. Rheology also showed evidence of chain-enlargements on the copolymers by means of an increase in the viscoelastic properties of the irradiated material.

  19. The effect of gamma irradiation on insect pest of rice in storage

    International Nuclear Information System (INIS)

    This study was conducted to determine the effect of gamma irradiation on insect pest of rice, stored for a period of 24 months, and packed in four different packaging materials. They were then exposed to gamma radiation using Gamma Cell 220, in a 60Co source. Samples were randomly sampled at the initial storage period and there after at 3 months interval. At each sampling time the grain weight loss and insect count, both dead and alive, were determined. The increasing dosages of irradiation did not show any consistent effect on the insect population in all the four packaging materials which indicated that the rice was already infested even before it was irradiated. The range of percentage weight loss for all the dosages of irradiation in all of the four packaging materials is 0.99 to 2.02. (A.J.)

  20. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    Science.gov (United States)

    Todoriki, Setsuko; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka; Kanamori, Norihito; Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio; Kawamoto, Shinichi

    2009-07-01

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a 60Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 °C. Additionally, the m-RNA levels of β-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  1. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    Energy Technology Data Exchange (ETDEWEB)

    Todoriki, Setsuko [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan)], E-mail: setsuko@affrc.go.jp; Bari, Latiful; Kitta, Kazumi; Ohba, Mika; Ito, Yasuhiro; Tsujimoto, Yuka [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan); Kanamori, Norihito [Japan International Research Center for Agricultural Science, Tsukuba, Ibaraki 305-8686 (Japan); Yano, Erika; Moriyama, Tatsuya; Kawamura, Yukio [School of Agriculture, Kinki University, Nara-city, Nara 631-8505 (Japan); Kawamoto, Shinichi [National Food Research Institute, Tsukuba, Ibaraki 305-8642 (Japan)

    2009-07-15

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a {sup 60}Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 deg. C. Additionally, the m-RNA levels of {beta}-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  2. Effect of gamma-irradiation on the survival of Listeria monocytogenes and allergenicity of cherry tomatoes

    International Nuclear Information System (INIS)

    The presence of Listeria monocytogenes in fresh produce is a growing concern because of the possibility of food-borne illness. Ionizing radiation is an effective non-thermal means of eliminating pathogenic bacteria in fresh produce; however, the effect of ionizing irradiation on the allergenic properties of the host commodities remains unknown. This study aimed (i) to determine the effective dose of gamma-irradiation in eliminating L. monocytogenes on whole cherry tomatoes and (ii) to evaluate the effect of gamma-irradiation on the allergenic properties of tomato proteins. Cherry tomatoes that were inoculated with a mixture of five L. monocytogenes strains were treated with gamma-rays from a 60Co source. A 1.25 kGy dose of gamma-irradiation was found to be sufficient to eliminate L. monocytogenes on whole cherry tomatoes. The immunoblot profile of serum samples obtained from two patients with tomato allergy revealed that gamma-irradiation did not affect the allergenicity of tomato proteins for up to 7 days after irradiation when the tomatoes were stored at 20 deg. C. Additionally, the m-RNA levels of β-fructofuranosidase, polygalacturonase, pectin esterase, and superoxide dismutase, the main allergenic proteins in tomato, were not affected by the applied irradiation dose. Thus, this study demonstrated that a 1.25 kGy dose of gamma-irradiation effectively eliminates L. monocytogenes on cherry tomatoes without affecting the expression of allergenic proteins in the fruits.

  3. Production of modified starches by gamma irradiation

    International Nuclear Information System (INIS)

    As a new processing method for the production of modified starch, gamma irradiation and four kinds of inorganic peroxides were applied to commercial corn starch. The addition of inorganic peroxides without gamma irradiation or gamma irradiation without the addition of inorganic peroxides effectively decreased initial viscosity, but did not sufficiently keep viscosity stable. The combination of adding ammonium persulfate (APS) and gamma irradiation showed the lowest initial viscosity and the best stability out of the tested four kinds of inorganic peroxides. Among the tested mixing methods of APS, soaking was found to be more effective than dry blending or spraying. Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability became feasible by the control of gamma irradiation dose levels and the amount of added APS to starch

  4. The influence of {sup 60}Co gamma radiation on the action of phenolic compounds Anadenanthera colubrina (Vell.) Brenan in the microbiological control of crude extracts

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo Henrique F. dos; Silva, Edvane B. da, E-mail: santosghf@hotmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR); Sena, Kesia Xisto da Fonseca R. de; Silva, Bruna L., E-mail: kxfrs@bol.com.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Antibioticos; Lima, Claudia S. de A., E-mail: claudia.salima@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    2009-07-01

    Anadenanthera colubrina (Vell.) Brenan, known popularly as angico is a tree founded in northeastern of Brazil, and has great economic and ecological interest. These trees are characterized by high levels of tannins. To evaluate the influence of gamma radiation in plant extracts of barks and leaves of angico, we got extracts of barks and leaves in 70% ethanol, which was filtered and evaporated until dryness. It were classified in four groups (non-irradiated, 5; 7.5 and 10 kGy). The total phenols were quantified by Folin-Ciocalteau method, and the tannins, using the precipitation of casein. The antimicrobial activity of extracts was observed using the paper disk diffusion methods against Gram-positive, Gram-negative, acid-alcohol-resistant bacteria: and yeasts. The halos greater than 10 mm were considered actives. It was also performed the Minimal Inhibitory Concentration (MIC) using Gram positive and alcohol-acid resistant bacteria. The results showed that tannins of A. colubrina, were 52 to 57% of total phenols, and leaves, 58 to 60%. The percentage of total phenols and tannins in the barks and leaves of A. colubrina have not statistically significant change when compared with the irradiated control. These results suggest that A. colubrina has antimicrobial activity against the Gram-positive and alcohol-acid -resistant bacteria, confirmed by MIC. The extracts of leaves it was additionally actives against the Gram-negative and against the yeast C. albicans. These results show that the gamma radiation has not influence about the antimicrobial activity of crude extracts of barks and leaves of A. colubrina. (author)

  5. The influence of 60Co gamma radiation on the action of phenolic compounds Anadenanthera colubrina (Vell.) Brenan in the microbiological control of crude extracts

    International Nuclear Information System (INIS)

    Anadenanthera colubrina (Vell.) Brenan, known popularly as angico is a tree founded in northeastern of Brazil, and has great economic and ecological interest. These trees are characterized by high levels of tannins. To evaluate the influence of gamma radiation in plant extracts of barks and leaves of angico, we got extracts of barks and leaves in 70% ethanol, which was filtered and evaporated until dryness. It were classified in four groups (non-irradiated, 5; 7.5 and 10 kGy). The total phenols were quantified by Folin-Ciocalteau method, and the tannins, using the precipitation of casein. The antimicrobial activity of extracts was observed using the paper disk diffusion methods against Gram-positive, Gram-negative, acid-alcohol-resistant bacteria: and yeasts. The halos greater than 10 mm were considered actives. It was also performed the Minimal Inhibitory Concentration (MIC) using Gram positive and alcohol-acid resistant bacteria. The results showed that tannins of A. colubrina, were 52 to 57% of total phenols, and leaves, 58 to 60%. The percentage of total phenols and tannins in the barks and leaves of A. colubrina have not statistically significant change when compared with the irradiated control. These results suggest that A. colubrina has antimicrobial activity against the Gram-positive and alcohol-acid -resistant bacteria, confirmed by MIC. The extracts of leaves it was additionally actives against the Gram-negative and against the yeast C. albicans. These results show that the gamma radiation has not influence about the antimicrobial activity of crude extracts of barks and leaves of A. colubrina. (author)

  6. Dose-dependent and gender-related radiation-induced transcription alterations of Gadd45a and Ier5 in human lymphocytes exposed to gamma ray emitted by 60Co

    International Nuclear Information System (INIS)

    Growth arrest DNA damage-inducible 45a gene (Gadd45a) and immediate early response gene 5 (Ier5) have been emphasised as ideal radiation bio-markers in several reports. However, some aspects of radiation-induced transcriptional alterations of these genes are unknown. In this study, gender-dependency and dose-dependency as two factors that may affect radiation induced transcription of Gadd45a and Ier5 genes were investigated. Human lymphocyte cells from six healthy voluntary blood donors (three women and three men) were irradiated in vitro with doses of 0.5-4.0 Gy from a 60Co source and RNA isolated 4 h later using the High Pure RNA Isolation Kit. Dose and gender dependency of radiation-induced transcriptional alterations of Gadd45a and Ier5 genes were studied by quantitative real-time polymerase chain reaction. The results showed that as a whole, Gadd45a and Ier5 gave responses to gamma rays, while the responses were independent of radiation doses. Therefore, regardless of radiation dose, Gadd45a and Ier5 can be considered potential radiation bio-markers. Besides, although radiation-induced transcriptional alterations of Gadd45a in female and male lymphocyte samples were insignificant at 0.5 Gy, at other doses, their quantities in female samples were at a significantly higher level than in male samples. Radiation induced transcription of Ier5 of females samples had a reduction in comparison with male samples at 1 and 2 Gy, but at doses of 0.5 and 4 Gy, females were significantly more susceptible to radiation-induced transcriptional alteration of Ier5. (authors)

  7. Gamma irradiations of the seeds and pollen grains of oil palm (Elaeis guineensis Jacq.)

    International Nuclear Information System (INIS)

    The pollen grains and seeds of oil palm (Elaeis guineensis Jacq.) were irradiated with up to 1400 Gy of gamma rays from a 60Co source. Pollen viability tests and subsequent development of embryos from the irradiated seeds showed that a dosage of up to 50 Gy could be tolerated by both the pollen grains and the seeds. Higher doses caused a drastic drop in the germination of seeds, thus reducing the potential size of any population for further studies. Plants of high bunch production were identified in both irradiated and non-irradiated materials. The potential use of gamma irradiation to induce useful mutation in the characters contributing to yield in the oil palm is discussed. (author). 2 refs, 3 figs, 1 tab

  8. Determination of the correction factor for attenuation, dispersion and production of electrons (Kwall) in the wall of graphite of a ionization chamber Pattern National Type CC01 in fields of gamma radiation of 60Co

    International Nuclear Information System (INIS)

    It was determined the Kwall correction factor for the wall of graphite of the chamber of the pattern national type CC01 series 133 for a radiation field Gamma of 60Co. With this end to measured the currents of ionization l(x) as function of the thickness of the wall of the chamber: X=4,8,12,16 and 20 mm.The mensurations for each thickness consisting of three groups, of sizes n = 30 or 60 data for each group; obtaining 8 complete groups of mensurations independent in eight different dates.The determinate the factor carried out using three regression models: lineal, logarithmic and quadratic, models that were tried to validate with the tests of : i) Shapiro-Wilk and χ2 for the normality of the entrance data ii) Tests of Bartlett for variances homogeneity among groups for each thickness iii) The tests of Duncan for the stockings among groups of each thickness, and iv) The tests of adjustment lack (LOF) for the models used. Nevertheless, alone the models of the group of corresponding mensurations at 01-03-2000 17-08-2001 they can be validated by LOF, but not for tests of normality and homogeneity of variances. Among other assignable causes of variation we have: i) The values captured by the system of mensuration of the variables of it influences: pressure, temperature and relative humidity dont belong together with the existent ones to the moment to capture the l(x). ii) The mensuration room presents flows of air, for what was suited o diminish their volume and to eliminate the flows of air. iii) A protocol settled down of taking of measures that it consisted in: - Pre-irradiation 5 minutes the chamber after the change of polarity and hood change, with a period of stabilization of 5 minutes after the pre-irradiation. - Pre-irradiation for 5 minutes before the taking of the readings, with the object of eliminating variation sources assigned to currents of escapes or due variations to transitory. iv) To realize corrections for relative humidity of agreement with the

  9. Experimental calibration and determination of the relative response for Lif: Mg, Ti(TLD-100) dosemeters at 60Co gamma and 60 kVp X-ray energies

    International Nuclear Information System (INIS)

    The thermoluminescence efficiency of LiF: Mg, Ti (TLD-100) dosemeters has been determined for photon beams from 60Co gamma rays and 60 kVp X-rays. It has been proven that light yield varies as a function of the photon energy. An experiment was performed using an X-ray beam whose spectrum has been determined by an X-ray fluorescence method. This enabled a direct calculation of the absorbed doses in the T1 material for the different operation conditions. These values and the experimental ones from measuring T1 intensities have been used to obtain the efficiency for energy X-ray spectrum. From the above values, the dosemeter T1 response, relative to 60Co, has been evaluated. (author)

  10. Determination of the correction factor for attenuation, dispersion and production of electrons (K{sub wall}) in the wall of graphite of a ionization chamber Pattern National Type CC01 in fields of gamma radiation of {sup 60}Co; Determinacion del factor de correccion por atenuacion, dispersion y produccion de electrones (K{sub wall}) en la pared de grafito de una Camara de Ionizacion Patron Nacional Tipo CC01 en campos de radiacion gamma de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T.; Morales P, J.; Cruz E, P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-12-15

    It was determined the Kwall correction factor for the wall of graphite of the chamber of the pattern national type CC01 series 133 for a radiation field Gamma of {sup 60}Co. With this end to measured the currents of ionization l(x) as function of the thickness of the wall of the chamber: X=4,8,12,16 and 20 mm.The mensurations for each thickness consisting of three groups, of sizes n = 30 or 60 data for each group; obtaining 8 complete groups of mensurations independent in eight different dates.The determinate the factor carried out using three regression models: lineal, logarithmic and quadratic, models that were tried to validate with the tests of : i) Shapiro-Wilk and {chi}{sup 2} for the normality of the entrance data ii) Tests of Bartlett for variances homogeneity among groups for each thickness iii) The tests of Duncan for the stockings among groups of each thickness, and iv) The tests of adjustment lack (LOF) for the models used. Nevertheless, alone the models of the group of corresponding mensurations at 01-03-2000 17-08-2001 they can be validated by LOF, but not for tests of normality and homogeneity of variances. Among other assignable causes of variation we have: i) The values captured by the system of mensuration of the variables of it influences: pressure, temperature and relative humidity don{sup t} belong together with the existent ones to the moment to capture the l(x). ii) The mensuration room presents flows of air, for what was suited o diminish their volume and to eliminate the flows of air. iii) A protocol settled down of taking of measures that it consisted in: - Pre-irradiation 5 minutes the chamber after the change of polarity and hood change, with a period of stabilization of 5 minutes after the pre-irradiation. - Pre-irradiation for 5 minutes before the taking of the readings, with the object of eliminating variation sources assigned to currents of escapes or due variations to transitory. iv) To realize corrections for relative humidity of

  11. Influence of gamma irradiation on conductivity of YBa2Cu3O7

    Science.gov (United States)

    Manjunatha, H. C.

    2015-08-01

    We report a study on influence of gamma irradiation on conductivity of YBa2Cu3O7. We have measured the mass attenuation coefficient, effective atomic number, electron density and electrical conductivity for various gamma sources of energy ranging from 0.084 MeV to 1.330 MeV (170Tm, 57Co, 141Ce, 203Hg, 51Cr, 113Sn, 22Na, 137Cs, 60Co, 22Na and 60Co). The measured values agree with the theoretical values. The values of these parameters have been found to change with energy and interaction of gamma. We find evidence for a variation of the electrical conductivity of YBa2Cu3O7 with the irradiated photon energy and this variation is shown in figures up to 105 MeV. The variations of effective atomic number and electron density with energy are shown graphically for all photon interactions. Conductivity found to vary with the energy of the irradiated gamma radiation and interaction process of gamma. This kind of studies is important in the field of superconductivity.

  12. Effect of {sup 60}Co gamma radiation on the levels of phenolic compounds from crude extracts of bark of Spondias luta L

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo H.F.; Silva, Hianna A.M.F.; Melo, Mychely S., E-mail: santosghf@hotmail.com, E-mail: hiannaamfs@gmail.com, E-mail: mychely.melo@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Silva, Edvane B., E-mail: edvborges@yahoo.com [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil). Centro Academinco de Vitoria

    2013-07-01

    Spondias luta L. (Anacardiaceae), popularly known as cajazeira, is a plant widespread in several regions of Brazil, famous for containing phenolic compounds, which are responsible for your characteristic astringent. Ionizing radiations have the ability to cross the material, ionizing atoms and molecules, causing changes in atoms and molecules important. It is known ionizing radiation promotes quantitative and qualitative changes in plant materials, increasing, decreasing or inactivating secondary substances. The objective of this work was to evaluate the effect of gamma radiation as a modifier of the activity of the phenolic compounds of the bark extract of S. luta L. Methods: For the dosage of phenol extracts (control, irradiated with 5 kGy, 10 kGy, 15 kGy and 20 kGy) were diluted in methanol to a final concentration of 200 mg / L. In test tubes were added 50 μL of extract plus 1 ml of distilled water and 500 μl of Folin (diluted 1:10). After 10 minutes in a dark chamber was added 2.5 ml of calcium carbonate to 20% and the content of the tube was homogenized. After 20 minutes was performed with a spectrophotometer at 735 nm. The assay was performed in triplicate and calculated from a standard curve solution of gallic acid and expressed in μEAG (GAE/mg extract). Results: The control extracts, irradiated to 5 kGy, 10 kGy, 15 kGy and 20 kGy, had, respectively, 6.25, 6.70, 6.25, 6.85, 6.45 μEAG/mg of extract. Conclusion: The results showed no significant change in the amount of phenolic compounds, showing that these compounds are radioresistant extract these doses. (author)

  13. Radiation safety and accident experience at gamma irradiation plants

    International Nuclear Information System (INIS)

    Gamma irradiation plants for the sterilization of medical products, preservation of food grains and for various other applications employ multikilocurie 60Co sealed sources inside shielded irradiation cells. A number of interlocks are provided between the cell entry door and the source raise mechanisms, in order to prevent the entry of any person to the cell when the source is in the exposed condition. The present paper gives the general safety features and the interlocks employed in these plants along with the safety features of irradiation plants at BARC, namely 106 Ci Isomed plant for the sterilization of medical products, 105 Ci FIPLY plant for research in food preservation and 105 Ci PANBIT plant for industrial research. Over the last two decades five cases of accidental exposure have been reported in literature in which the operator gained entry to the irradiation cell when the source was in the exposed condition. Two of these cases resulted in fatalities while the remaining three cases resulted in hospitalization of the exposed individuals for six to seven weeks. A brief outline of these accidental exposure cases and the causes of the accidents are discussed in this paper. (author). 19 refs

  14. Thermoluminescence in gamma irradiated iPP-VGVGCNF

    International Nuclear Information System (INIS)

    Nanocomposites have been obtained by dispersing various amounts of vapor grown carbon nanofibers within isotactic polypropylene via melt mixing. The as obtained nanocomposites were gamma irradiated at various integral doses by using a 60Co source. The irradiation was performed in air, at room temperature, and at a dose rate of about 1 kGy/h up to an integral dose of 28 kGy. Thermoluminescence investigations revealed the role of carbon nanotubes in the radiation-induced modification of polymer-based nanocomposites. Almost all samples (pristine polymer and polymer-based nanocomposites irradiated and not irradiated) showed two overlapping thermoluminescence signals. It is concluded that the dispersion of carbon nanotubes decreases the amount of trapped electrons improving eventually the radiation stability of the polymeric matrix. The low temperature thermoluminescence peak was tentatively associated to melting phenomena. The origin of the high temperature thermoluminescence peak is more complex. Nevertheless, the experimental data suggests that this peak is sensitive to the polymer-filler interface.

  15. Thermoluminescence in gamma irradiated iPP-VGVGCNF

    Energy Technology Data Exchange (ETDEWEB)

    Cherestes, Margareta [S. C. Dozimed SRL, Bucharest (Romania); Constantinescu, Livia Maria [University of Bucharest, Faculty of Physics, Magurele, Bucharest (Romania); Chipara, Dorina Magdalena, E-mail: dchipara@utpa.edu [The University of Texas Pan-American, Department of Physics and Geology, Edinburg, TX 78539 (United States); Cherestes, Codrut [S. C. Dozimed SRL, Bucharest (Romania); Chipara, Mircea [The University of Texas Pan-American, Department of Physics and Geology, Edinburg, TX 78539 (United States)

    2013-06-15

    Nanocomposites have been obtained by dispersing various amounts of vapor grown carbon nanofibers within isotactic polypropylene via melt mixing. The as obtained nanocomposites were gamma irradiated at various integral doses by using a {sup 60}Co source. The irradiation was performed in air, at room temperature, and at a dose rate of about 1 kGy/h up to an integral dose of 28 kGy. Thermoluminescence investigations revealed the role of carbon nanotubes in the radiation-induced modification of polymer-based nanocomposites. Almost all samples (pristine polymer and polymer-based nanocomposites irradiated and not irradiated) showed two overlapping thermoluminescence signals. It is concluded that the dispersion of carbon nanotubes decreases the amount of trapped electrons improving eventually the radiation stability of the polymeric matrix. The low temperature thermoluminescence peak was tentatively associated to melting phenomena. The origin of the high temperature thermoluminescence peak is more complex. Nevertheless, the experimental data suggests that this peak is sensitive to the polymer-filler interface.

  16. Tolerance of edible flowers to gamma irradiation

    International Nuclear Information System (INIS)

    People have been eating flowers and using them in culinary creations for hundreds of years. Edible flowers are increasingly being used in meals as an ingredient in salads or garnish, entrees, drinks and desserts. The irradiation process is an alternative method that can be used in disinfestation of food and flowers, using doses that do not damage the product. The sensitivity of flowers to irradiation varies from species to species. In the present research was irradiated with doses up to 1 kGy some edible flowers to examine their physical tolerance to gamma-rays. Furthermore, high doses gamma irradiation causes petal withering, browning process and injury in edible flowers. (author)

  17. Tolerance of edible flowers to gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Koike, Amanda C.R.; Araujo, Michel M.; Costa, Helbert S.F.; Almeida, Mariana C.; Villavicencio, Anna Lucia C.H., E-mail: ackoike@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil)

    2011-07-01

    People have been eating flowers and using them in culinary creations for hundreds of years. Edible flowers are increasingly being used in meals as an ingredient in salads or garnish, entrees, drinks and desserts. The irradiation process is an alternative method that can be used in disinfestation of food and flowers, using doses that do not damage the product. The sensitivity of flowers to irradiation varies from species to species. In the present research was irradiated with doses up to 1 kGy some edible flowers to examine their physical tolerance to gamma-rays. Furthermore, high doses gamma irradiation causes petal withering, browning process and injury in edible flowers. (author)

  18. Effect of gamma irradiation on the behavioral properties of crotoxin

    Directory of Open Access Journals (Sweden)

    E.G. Moreira

    1997-02-01

    Full Text Available Crotoxin has been detoxified with gamma radiation in order to improve crotalic antiserum production. Nevertheless, present knowledge of the biological characteristics of irradiated crotoxin is insufficient to propose it as an immunizing agent. Crotoxin is known to increase the emotional state of rats and to decrease their exploratory behavior (Moreira EG, Nascimento N, Rosa GJM, Rogero JR and Vassilieff VS (1996 Brazilian Journal of Medical and Biological Research, 29: 629-632. Therefore, we decided 1 to evaluate the effects of crotoxin in the social interaction test, which has been widely used for the evaluation of anxiogenic drugs, and 2 to determine if irradiated crotoxin induces behavioral alterations similar to those of crotoxin in the social interaction, open-field and hole-board tests. Male Wistar rats (180-220 g were used. Crotoxin (100, 250, and 500 µg/kg was injected intraperitoneally 2 h before the social interaction test. Similarly, irradiated crotoxin (2000 Gy gamma radiation from a 60Co source was administered at the doses of 100, 250, and 500 µg/kg for the hole-board test, and at the doses of 1000 and 2500 µg/kg for the open-field and social interaction tests. ANOVA complemented with the Dunnett test was used for statistical analysis (P<0.05. Crotoxin decreased the social interaction time (s at the doses of 100, 250 and 500 µg/kg (means ± SEM from 51.6 ± 4.4 to 32.6 ± 3.7, 28.0 ± 3.6 and 31.6 ± 4.4, respectively. Irradiated crotoxin did not induce behavioral alterations. These results indicate that 1 crotoxin may be an anxiogenic compound, and 2 in contrast to crotoxin, irradiated crotoxin was unable to induce behavioral alterations, which makes it a promising compound for the production of crotalic antiserum

  19. Crosslinking of metallocenic α-olefin propylene copolymers by vacuum gamma irradiation

    International Nuclear Information System (INIS)

    Metallocenic polypropylene and copolymers with 3.7, and 9.2 mol% of hexene and 3.0 mol% of octadecene comonomer content were synthesized without the presence of additives and irradiated with 60Co gamma radiation under vacuum at room temperature. Size Exclusion Cromatography and gel extraction data showed that scission reactions predominate over crosslinking in the homopolymer and that there is a dose from where crosslinking started to increase considerably, in the irradiated copolymers. Rheology also showed evidence of chain-enlargements on the copolymers by means of an increase in the viscoelastic properties of the irradiated material. - Highlight: ► Vacuum gamma irradiation of metallocenic isotactic propylene copolymers. ► We examine the radioinduced changes in rheological properties and molecular weights. ► Radioinduced crosslinking in the copolymers, without the presence of additives. ► Dependence of crosslinking with copolymer′s length and amount of short branches.

  20. Thermal analysis of polypropylene modified by gamma irradiation composites under outdoor conditions

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, Luiz G.H.; Oliani, Washington L.; Lugao, Ademar B.; Parra, Duclerc F., E-mail: dfparra@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This work reports the influence of the clay in the degradation process of the HMSPP.The polypropylene (PP) was irradiated under acetylene atmosphere in gamma irradiation source ({sup 60}Co) to obtain the HMSPP (high melt strength polypropylene). Composites of HMSPP were processed in twin-screw extruder with clay Cloisite 20A and Maleic Anhydride (PP-g-MA) as coupling agent. The obtained composites were exposed under outdoor conditions for 6 months. The ageing effects were characterized by Differential Scanning Calorimetry (DSC), Thermogravimetry Analysis (TGA). Chemical oxidation was evaluated by Carbonyl Index (IC) through infrared Spectroscopy (FT-IR). The results showed correlation between carbonyl index and ageing time. (author)

  1. Response of reptilian live to external gamma irradiation

    International Nuclear Information System (INIS)

    Adult healthy specimens of Uromastix hardwickii were exposed to three doses (i.e. 2.25, 4.50 and 9.00 Gy) of gamma radiation from a 60Co source (experimental group). Five animals were sacrificed at each post-irradiation intervals of 1, 2, 3, 7 and 14 days. The liver was fixed in Bouin's fluid and after processing in a routine way, it was examined histologically. Five sham-irradiated animals (control group) were also sacrificed to compare the results. Low dose (i.e. 2.25 Gy) did not produce any apparent radiolesions in the liver. Changes in the form of cytoplasmic degranulation, swollen hepatocytes, pycnosis, increases in bile pigmentation were noticed after 4.50 and 9.00 Gy gamma ray exposure. Hyperaemia, widening of sinusoids and cytoplasmic vacuolation were also noticed in 9.00 Gy group. The liver exhibited normal picture on day 14 after exposure to both the doses. The radiolesions were found dose dependent. (author)

  2. 60Co放射及微量元素锌对钛种植体骨融合的影响%Effect of60Co irradiation and trace element zinc on implant-bone fusion

    Institute of Scientific and Technical Information of China (English)

    陈海军; 张安生; 朱孝春; 钱奇春; 于淑湘; 杨博程; 张静波; 南福清; 林均舟

    2015-01-01

    BACKGROUND:Zinc supplementation can accelerate implant-bone fusion. OBJECTIVE:To observe the effect of 60Co irradiation and trace element zinc on implant-bone fusion. METHODS:A total of 36 adult male rabbits were involved. One piece of titanium implant was placed into the proximal end of the rabbit's bilateral tibial heads respectively to set up the animal model with titanium implants. Then the animals were randomly divided into four groups. Twenty-four hours after implantation, 10 g/L zinc sulfate was administered intramuscularly to the animals in the zinc supplement group at the dose of 4 mg/kg, once per day; 9 g/L normal saline was administered intramuscularly to the animals in the control group at the dose of 4 mg/kg, once per day. The animals in the 60Co irradiation group received 60Co irradiation at 2, 4, 6 days at the dose of 15 Gy per day, and 24 hours after implantation, 9 g/L normal saline was administered intramuscularly at the dose of 4 mg/kg, once per day; while those in the 60Co irradiation and zinc supplement group received 60Co irradiation at 2, 4, 6 days at the dose of 15 Gy per day, and 24 hours after implantation, 10 g/L zinc sulfate was administered intramuscularly to the animals at the dose of 4 mg/kg, once per day. The animals were kiled at 1, 4, 12 weeks after treatment. Stereomicroscope was used to observe the histomorphology on the implant-bone interface. RESULTS AND CONCLUSION:Compared to other groups, at the same time, more fibroblasts and fibrous fusion were observed around the implants from the 60Co irradiation group while less bone tissue, especialy mature bone tissue, was observed. On the contrary, at the same time, the surfaces of the implants from the zinc supplement group showed more osteoblasts and bone fusion. Mature bone tissue was observed around the implants at the 4th week after implantation indicating that zinc supplement can accelerate the new bone formation on the implant-bone interface at 1-4 weeks after treatment to

  3. Study of uptake and endocytosis of gamma rays-irradiated crotoxin by mice peritoneal macrophages

    International Nuclear Information System (INIS)

    The purpose was to investigate the uptake and endocytosis of 2000 Gy 60Co irradiated crotoxin through mouse peritoneal macrophages, correlating with native one and another non related protein, the ovalbumin. Native (CTXN) or 2000 Gy 60 Co γ-rays (dose rate 540 Gy/hour) irradiated crotoxin (CTXI) or ovalbumin processed of same manner (OVAN - OVAI) were offered to mouse peritoneal macrophages and their uptake was evaluated by immunohistochemistry and quantitative in situ ELISA. The involvement of scavenger receptors (ScvR) was evaluated by using blockers drugs (Probuco-PBC or Dextran Sulfate - SD) or with nonspecific blocking using fetal calf serum (FBS). The morphology and viability of macrophages were preserved during the experiments. CTXI showed irradiation-induced aggregates and formation of oxidative changing were observed on this protein after gamma rays treatment. By immunohistochemistry we could observe heavy stained phagocytic vacuole on macrophages incubated with CTXI, as compared with CTXN. Quantitatively by in situ ELISA, the sema pattern was observed, displaying a 2-fold CTXI incorporation. In presence of PBC or SD we could find a significant decrease of CTXI uptake but not of CTXN. However the CTXN uptake was depressed by FBS, not observed with CTXI. OVA, after gamma rays treatment, underwent a high degradation suffering a potent incorporation and metabolism by macrophages, with a major uptake of OVAI in longer incubation (120 minutes). Gamma rays (60 Co) produced oxidative changes on CTX molecule, leading to a uptake by ScvR-mice peritoneal macrophages, suggesting that the relation antigen-presenting cells and gamma rays-modified proteins are responsible for the better immune response presented by irradiated antigens. (author)

  4. Comunicación corta. RADIOESTIMULACIÓN DE LA GERMINACIÓN EN Stevia rebaudiana CULTIVAR KH-IAN VC-142 (EIRETÉ), MEDIANTE EL EMPLEO DE RAYOS GAMMA 60CO

    OpenAIRE

    María C. González; Héctor D. Nakayama

    2015-01-01

    El presente trabajo tuvo como objetivo evaluar el efecto de bajas dosis de rayos gamma 60 Co en la germinación de las semillas de Stevia rebaudiana . Para ello se irradiaron semillas del cultivar KH-IAN VC-142 (Eireté), con dosis de 10 a 90 Gray (Gy). Se determinó que todas las dosis empleadas incrementaron el número de semillas germinadas pero la dosis de 10 Gy fue la que provocó la mayor estimulación en la germinación de las semillas.

  5. Comunicación corta. RADIOESTIMULACIÓN DE LA GERMINACIÓN EN Stevia rebaudiana CULTIVAR KH-IAN VC-142 (EIRETÉ, MEDIANTE EL EMPLEO DE RAYOS GAMMA 60CO

    Directory of Open Access Journals (Sweden)

    María C. González

    2015-01-01

    Full Text Available El presente trabajo tuvo como objetivo evaluar el efecto de bajas dosis de rayos gamma 60 Co en la germinación de las semillas de Stevia rebaudiana . Para ello se irradiaron semillas del cultivar KH-IAN VC-142 (Eireté, con dosis de 10 a 90 Gray (Gy. Se determinó que todas las dosis empleadas incrementaron el número de semillas germinadas pero la dosis de 10 Gy fue la que provocó la mayor estimulación en la germinación de las semillas.

  6. Resistance of acrylic vessel to gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Andre Cavalcanti; Menezes, Maria Angela de B.C.; Pereira, Marcio Tadeu; Rocha, Nirlando Antonio; Vilela, Jefferson Jose, E-mail: andreccarneiro@gmail.com, E-mail: menezes@cdtn.br, E-mail: mtp@cdtn.br, E-mail: nar@cdtn.br, E-mail: jjv@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Braga, Mario Roberto Martins S.S., E-mail: mariomartins@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

    2013-07-01

    This paper describes the preliminary studies made in acrylic material in order to verify the effects of radiolysis in acrylic recipients in which the uranium ore standards are conditioned and check if the material is able to keep the {sup 222}Rn inside the vessel. The preliminary results after gamma irradiation of two kinds of recipients indicate no differences between the vessels irradiated and the ones no irradiated, related to color changes and tension resistance. (author)

  7. Use of Gamma Irradiation for Prolonging Shelf Life of Garden Pea (Pisum sativum L.)

    International Nuclear Information System (INIS)

    Garden pea pods of variety 'Arkel' were irradiated with 5 doses of 60Co gamma rays ranging from 0.5-3.0 kGy and stored at ambient temperature up to 9 days along with control to study the effect of radiation in prolonging shelf life of pea pods and stabilizing its market demand. Physiological weight loss (%) decreased as the doses of gamma radiation increased. Minimum weight loss was noted in pods irradiated with 3.0 kGy gamma rays compared to control. Decay loss % showed an inverse relationship with dose of gamma radiation. Minimum decay loss was recorded with 3.0 kGy gamma ray dose. Pea pods irradiated with 1.0 kGy gamma rays recorded maximum sugar content. Pods irradiated with 0.5 kGy and 1.0 kGy gamma rays retained their green colour for a longer period. Based on a 9 point hedonic scale the highest acceptability for appearance, taste and texture was observed in pods treated with the 1.0 kGy dose. (author)

  8. Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the NIM, China and the BIPM in 60Co gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D.; Wang, K.; Fan, Y.; Jin, S.; Yang, X.

    2016-01-01

    An indirect comparison of the standards for air kerma of the National Institute of Metrology (NIM), China and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in November 2015. The comparison result, evaluated as a ratio of the NIM and the BIPM standards for air kerma, is 0.9997 with a combined standard uncertainty of 2.7 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  9. Influence of hormonal anabolic agents on hematopoietic system of gamma-irradiated laying hens

    International Nuclear Information System (INIS)

    Thirty laying hens were randomly divided into 3 groups (control), thiourea and estradiol benzoate) of 10 hens each, to find out the hematological response to ionizing radiation and hormonal treatments. Five hens from each group were exposed to 600 r whole body 60Co-gamma rays. Hematological parameters and plasma proteins were measured after 4 weeks post-irradiation gamma-irradiation significantly decreased WBCs, Hb, plasma total proteins and albumin. Estradiol benzoate injection significantly increased RBCs, Hb, plasma total proteins and albumin indicating that estradiol benzoate could minimize the reducing effect of gamma-rays. Thiourea administration depressed all of the studied hematological parameters and significantly increased plasma total proteins and significantly increased plasma total proteins and globulin. It can be concluded that ionizing radiation decreased the production and increased the destruction of Hb, RBCs, WBCs and plasma proteins. 4 tab

  10. Enact of Glutathione(GSH/GSSG) Contents of Fermented Ginseng on the {gamma}-irradiated Liver of Mice

    Energy Technology Data Exchange (ETDEWEB)

    Ko, In Ho [Dept. of Radiology Technology, Jeju Halla College, Jeju (Korea, Republic of)

    2006-03-15

    The radioprotective effects of white and fermented ginseng on liver damage induced by {sup 60}Co {gamma}-ray were investigated. To one group of ICR male mice were given white(150 mg/kg/day for 7 days, orally) and fermented ginseng(150 mg/kg/day for 7 days, orally) before {sup 60}Co {gamma}--ray irradiation. To another group were irradiated by 5 Gy(1.01 Gy/min) dose of {sup 60}Co {gamma}--ray. Contrast group were given with saline(0.1 mL). The levels of reduced(GSH) and oxidized(GSSG) glutathione in liver tissue were measured. In the fermented(150 mg/kg) and white ginseng(150 mg/kg) groups than irradiation group, the GSH levels were significantly increased, but the GSSG levels were significantly decreased. The ratio of GSSG/total GSH was significantly decreased in the fermented(150 mg/kg) and white ginseng(150 mg/kg) groups than irradiation group. In the fermented(150 mg/kg) groups than white ginseng(150 mg/kg) groups the GSH levels were significantly increased. The radioprotective effects of fermented(150 mg/kg) groups than white ginseng(150 mg/kg) groups were increased.

  11. Sensitivity of P-Channel MOSFET to X- and Gamma-Ray Irradiation

    Directory of Open Access Journals (Sweden)

    Milić Pejović

    2013-01-01

    Full Text Available Investigation of Al-gate p-channel MOSFETs sensitivity following irradiation using 200 and 280 kV X-ray beams as well as gamma-ray irradiation of 60Co in the dose range from 1 to 5 Gy was performed in this paper. The response followed on the basis of threshold voltage shift and was studied as a function of absorbed dose. It was shown that the most significant change in threshold voltage was in the case of MOSFET irradiation in X-ray fields of 200 kV and when the gate voltage was +5 V. For practical applications in dosimetry, the sensitivity of the investigated MOSFETs was also satisfactory for X-ray tube voltage of 280 kV and for gamma rays. Possible processes in gate oxide caused by radiation and its impact on the response of MOSFETs were also analyzed in this paper.

  12. A comparison of the biological effects of 125I seeds continuous low-dose-rate radiation and 60Co high-dose-rate gamma radiation on non-small cell lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Zhongmin Wang

    Full Text Available To compare the biological effects of 125I seeds continuous low-dose-rate (CLDR radiation and 60Co γ-ray high-dose-rate (HDR radiation on non-small cell lung cancer (NSCLC cells.A549, H1299 and BEAS-2B cells were exposed to 125I seeds CLDR radiation or 60Co γ-ray HDR radiation. The survival fraction was determined using a colony-forming assay. The cell cycle progression and apoptosis were detected by flow cytometry (FCM. The expression of the apoptosis-related proteins caspase-3, cleaved-caspase-3, PARP, cleaved-PARP, BAX and Bcl-2 were detected by western blot assay.After irradiation with 125I seeds CLDR radiation, there was a lower survival fraction, more pronounced cell cycle arrest (G1 arrest and G2/M arrest in A549 and H1299 cells, respectively and a higher apoptotic ratio for A549 and H1299 cells than after 60Co γ-ray HDR radiation. Moreover, western blot assays revealed that 125I seeds CLDR radiation remarkably up-regulated the expression of Bax, cleaved-caspase-3 and cleaved-PARP proteins and down-regulated the expression of Bcl-2 proteins in A549 and H1299 cells compared with 60Co γ-ray HDR radiation. However, there was little change in the apoptotic ratio and expression of apoptosis-related proteins in normal BEAS-2B cells receiving the same treatment.125I seeds CLDR radiation led to remarkable growth inhibition of A549 and H1299 cells compared with 60Co HDR γ-ray radiation; A549 cells were the most sensitive to radiation, followed by H1299 cells. In contrast, normal BEAS-2B cells were relatively radio-resistant. The imbalance of the Bcl-2/Bax ratio and the activation of caspase-3 and PARP proteins might play a key role in the anti-proliferative effects induced by 125I seeds CLDR radiation, although other possibilities have not been excluded and will be investigated in future studies.

  13. Dielectric relaxation of gamma irradiated muscovite mica

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Navjeet [Department of Physics, Guru Nanak Dev University, Amritsar, Punjab 143005 (India); Singh, Mohan, E-mail: mohansinghphysics@gmail.com [Department of Physics, Guru Nanak Dev University, Amritsar, Punjab 143005 (India); Singh, Lakhwant [Department of Physics, Guru Nanak Dev University, Amritsar, Punjab 143005 (India); Awasthi, A.M. [Thermodynamics Laboratory, UGC-DAE Consortium for Scientific Research, Indore 452001 (India); Lochab, S.P. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

    2015-03-15

    Highlights: • The present article reports the effect of gamma irradiation on the dielectric relaxation characteristics of muscovite mica. • Dielectric and electrical relaxations have been analyzed in the framework of dielectric permittivity, electric modulus and Cole–Cole formalisms. • The frequency dependent electrical conductivity has been rationalized using Johnsher’s universal power law. • The experimentally measured electric modulus and conductivity data have been fitted using Havriliak–Negami dielectric relaxation function. - Abstract: In the present research, the dielectric relaxation of gamma irradiated muscovite mica was studied in the frequency range of 0.1 Hz–10 MHz and temperature range of 653–853 K, using the dielectric permittivity, electric modulus and conductivity formalisms. The dielectric constants (ϵ′ and ϵ′′) are found to be high for gamma irradiated muscovite mica as compared to the pristine sample. The frequency dependence of the imaginary part of complex electric modulus (M′′) and dc conductivity data conforms Arrhenius law with single value of activation energy for pristine sample and two values of activation energy for gamma irradiated mica sample. The experimentally assessed electric modulus and conductivity information have been interpreted by the Havriliak–Negami dielectric relaxation explanation. Using the Cole–Cole framework, an analysis of real and imaginary characters of the electric modulus for pristine and gamma irradiated sample was executed which reflects the non-Debye relaxation mechanism.

  14. Stability of vitamin E content of {gamma}-irradiated biscuits

    Energy Technology Data Exchange (ETDEWEB)

    Taipina, Magda S.; Mastro, Nelida L. del [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: nlmastro@ipen.br; magtaipina@ig.com.br; Lamardo, Leda C.A. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil). Secao de Quimica Biologica]. E-mail: llamardo@ial.sp.gov.br

    2007-07-01

    The technology of food irradiation is seen by the industry as a means of ensuring food safety, since it exposes foods to ionizing radiation that kills insects, moulds and bacteria. The need to eliminate bacterial pathogens from read-to-eat food products must always be balanced with the maintenance of product quality. In addition to determining the effective ionizing radiation doses required for pathogen elimination the effects of irradiation on product chemistry, nutritional value and quality must also been determined. Vitamin E ({alpha}-tocopherol) is one of the most potent natural lipophilic antioxidants commonly present in the human diet. As it is considered a free radical scavenger there is a growing concern that irradiation might reduce the vitamin E content of food products prepared with ingredients rich in any of the dietary source of the vitamin. This work describes the effects of ionizing radiation on the vitamin E content of some biscuits commercially found in the market. Three lots of biscuits were used. Irradiation was performed in a {sup 60}Co Gammacell 220 source, dose rate of about 3.5 kGy/h at doses of 1 kGy and 3 kGy. For vitamin E determination samples were saponified with ethanolic potassium hydroxide in the presence of pyrogallol, and the tocopherols were extracted with petroleum ether. The absorbance was measured at 520 nm. From the obtained results it is possible to conclude that there was a notorious stability of the vitamin content of the biscuits submitted to gamma-irradiation at the assayed doses. (author)

  15. Key comparison BIPM.RI(I)-K4 of the absorbed dose to water standards of the PTB, Germany and the BIPM in 60Co gamma radiation

    Science.gov (United States)

    Kessler, C.; Burns, D. T.; Kapsch, R.-P.; Krauss, A.

    2016-01-01

    An indirect comparison has been made of the standards for absorbed dose to water in 60Co radiation of the Physikalisch-Technische Bundesanstalt, (PTB), Germany and of the Bureau International des Poids et Mesures (BIPM). The measurements at the BIPM were carried out in October 2015. The comparison result, based on the calibration coefficients for two transfer standards and evaluated as a ratio of the PTB and the BIPM standards for absorbed dose to water, is 0.9977 with a combined standard uncertainty of 3.8 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  16. Influence of natural antioxidants on lipid composition of beef burgers submitted to irradiation in {sup 60} Co source and electron beams; Influencia de antioxidantes naturais sobre o perfil lipidico de hamburgueres bovinos submetidos a irradiacao por {sup 60}Co e aceleradores de eletrons

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Reginaldo Almeida da

    2007-07-01

    Radiation processing has been employed in some countries as a mean of treatment to assure microbiological safety of meat and meat products, avoiding the occurrence of food-borne disease. The ionizing radiation may cause some undesirable changes on chemistry composition of food and the lipid oxidation is one of the main reactions. In meat products processing industry, the lipid composition is directly related to nutritional and sensory quality of the product. For preventing oxidation, use of antioxidants which can be synthetic or natural, has been practically applied in some products. Currently, most attention has been given to natural antioxidants from herbs and spices like rosemary and oregano. The aim this study was to assess the antioxidant effects of either rosemary and oregano extract in beef burgers submitted to irradiation in {sup 60}Co source with dose 6, 7 e 8 kGy, electron beams with dose 3,5 e 7 kGy and storage under freeze along 0, 45 e 90 days. The results showed that rosemary extract has the major antioxidant effects when it is used on heterogeneous food matrix like beef burger, but oregano extract was better efficient to delay lipid oxidation along storage time when it is used in synergism with rosemary and/or BHT/BHA. Although to have occurred changes in the fatty acids composition it was not possible to demonstrate a straight dependence of irradiation dose and/or storage time. Sensory analysis showed that between the samples prepared with natural antioxidants, the beef burger prepared with oregano has received better scores by panelists. Irradiated beef burger prepared with rosemary has received better scores when compared to non-irradiated one. The use of spices with antioxidant activity to avoid the oxidative damage in foods that contain fats in their formulation is thought to be promising to application in food facilities. (author)

  17. The effect of gamma irradiation on the germination and growth of certain Nigerian agricultural crops

    International Nuclear Information System (INIS)

    Gamma irradiation has been found to be very useful both for sterilisation in medicine and the preservation of food and cereals in nutrition and agriculture. This investigation was carried out to determine the effect of gamma irradiation on the subsequent germination and growth of irradiated seeds. Thirty seeds each of maize, okra and groundnut were irradiated to varying doses of 150, 300, 500, 700, 900, 1000 Gy using the 60Co gamma cell irradiator facility at the Centre for Energy Research and Development, Obafemi Awolowo University, Ile-Ife. These, as well as the controls (unirradiated seeds), were planted on the same day in an already prepared area of farmland during the rainy season to ensure a constant moisture flow. The times of germination and subsequent growth were monitored. Results show that maize, okra and groundnut seeds needed for planting can be safely stored using gamma irradiation. However, the study reveals that the number of germinated seeds and the growth rate for the crops decrease with increase in the radiation dose the seeds were exposed to. Third-degree polynomial equations were derived which describe the percentage germination of the crops at various levels of exposure. A chart of percentage germination of seeds versus exposure dose is also presented as a quick guide to farmers, policy makers and agricultural institutions. (note)

  18. The effect of gamma irradiation on the germination and growth of certain Nigerian agricultural crops

    Energy Technology Data Exchange (ETDEWEB)

    Mokobia, C E; Anomohanran, O [Department of Physics, Delta State University, Abraka, Delta State (Nigeria)

    2005-06-01

    Gamma irradiation has been found to be very useful both for sterilisation in medicine and the preservation of food and cereals in nutrition and agriculture. This investigation was carried out to determine the effect of gamma irradiation on the subsequent germination and growth of irradiated seeds. Thirty seeds each of maize, okra and groundnut were irradiated to varying doses of 150, 300, 500, 700, 900, 1000 Gy using the {sup 60}Co gamma cell irradiator facility at the Centre for Energy Research and Development, Obafemi Awolowo University, Ile-Ife. These, as well as the controls (unirradiated seeds), were planted on the same day in an already prepared area of farmland during the rainy season to ensure a constant moisture flow. The times of germination and subsequent growth were monitored. Results show that maize, okra and groundnut seeds needed for planting can be safely stored using gamma irradiation. However, the study reveals that the number of germinated seeds and the growth rate for the crops decrease with increase in the radiation dose the seeds were exposed to. Third-degree polynomial equations were derived which describe the percentage germination of the crops at various levels of exposure. A chart of percentage germination of seeds versus exposure dose is also presented as a quick guide to farmers, policy makers and agricultural institutions. (note)

  19. Development of modified starch by gamma irradiation

    International Nuclear Information System (INIS)

    The purpose of this study was to develop the production technology of modified starch. Corn starches were gamma irradiated at 0-110 kGy and the effect of irradiation dose levels on the physicochemical properties of corn starches were investigated. Blue value linearly decreased, while alkali number and solubility markedly increased as irradiation dose levels were increased. The optical transmittance increased as applied irradiation dose levels were increased in the temperature range of 65-95 deg. C. Water binding capacity and swelling power showed maximum value at 30 and 10 kGy, respectively and they tended to decrease thereafter. Gelatinization viscosity of the gamma irradiated starch considerably decreased as compared to that of the non-irradiated starch. Irradiation at 110kGy resulted in a marked reduction of peak viscosity and cooling viscosity at 30 deg. C by 100 and 300 times, respectively. The physicochemical properties of corn starch irradiated at 30 kGy were similar to those of commercial acid-modified starch, while those of corn starch irradiated at 100 kGy were similar to those if oxidized starch

  20. Effects of gamma irradiation and moisture absorption on mechanical properties of PA6/PTFE blends

    Institute of Scientific and Technical Information of China (English)

    罗文波; 肖华明; 谭江华; 吴国忠; 林明丽

    2008-01-01

    PA6/PTFE blends with varying polytetrafluoroethylene content from 3% to 15%(mass fraction) were irradiated by 60Co gamma-ray with various doses(20,50 and 100 kGy) under ambient conditions.Moisture absorption test,U-notched Charpy impact test and quasi-static tension and bending were conducted to investigate the effect of irradiation on moisture absorption and mechanical properties of the blends.It is shown that the exposure of the blend to 60Co irradiation improves the tensile modulus,tensile strength and flexural modulus due to irradiation induced cross-linking in PA6 phase.However,the Charpy impact strength of the blends is much lower than that of the original PA6 and it decreases slightly with the increase of irradiation dose.Moreover,the flexural modulus increases to a maximum value and then decreases with further increasing the PTFE content,and the moisture absorption decreases with the increase of the PTFE content and irradiation dose.

  1. Storage ability of gamma irradiated mango fruits

    International Nuclear Information System (INIS)

    Extension of shelf-life have been achieved by many methods. the most modern one is using gamma irradiation as a promising technology for the developing nations. The aim of this investigation is to study the effects of gamma irradiation either alone or in combination with Alar or Benlate on 'Hindi Be Senara' mature green fruits and also to determine the optimum treatment and maximum extension in shelf - life. Mature-green 'Hindi be sinara' mango fruits were taken from trees planted in commercial orchard in 'kerdasa'Giza

  2. UTN's gamma irradiation facility: design and concept

    International Nuclear Information System (INIS)

    UTN is building a multipurpose gamma irradiation facility which compromises of research and pilot scale irradiation cells in The Fifth Malaysia Plan. The paper high-lights the basic futures of the facility in terms of its design and selection including layout sketches. Plant performances and limitations are discussed. Plants safety is briefly highlighted in block diagrams. Lastly, a typical specification brief is tabled in appendix for reference purposes. (author)

  3. Microstructural study of Y1Ba2Cu3O7-x/Ag samples irradiated with 60Co γ rays at high doses

    International Nuclear Information System (INIS)

    We have investigated the damage induced by irradiation in Y1Ba2Cu3O7-x silver added samples. The samples were prepared with 0 and 6.5 wt% of silver and irradiated by high-energy γ irradiation (50-150 Mrad). The roles of silver and dosage irradiation are discussed in terms of their effects on microstructure, crystallinity, critical temperature (Tc) and zero-resistance temperature (T0). After irradiation, Tc decreased while the room-temperature electrical resistance increased by a factor of 8 for some of the samples. The difference in T0 between irradiated and non-irradiated YBCO samples was of the order of 10 K. We have found that the difference is bigger for silver-added samples. We have also observed several changes in diffraction patterns of YBCO and YBCO-silver samples. SEM images, EDS and XPS analysis showed that silver resided inside the grains as single atoms and as metallic clusters. The relative concentrations of the elements in samples were quantified by Auger electron spectroscopy. The values showed a gradual increase for radiation doses ranging between 0 and 100 Mrad. For doses up to 100 Mrad, Jc decreased because of the weak-link breakage induced by high doses of γ rays. (author)

  4. Study on the grafting of N-vinypyrrolidone onto xanthan gum by 60Co γ-irradiation and properties of the grafted copolymer

    International Nuclear Information System (INIS)

    Simultaneous radiation grafting method (60Co γ-rays as the radiation source) was used to prepare xanthan gum-graft-N-vinypyrrolidone (XG-g-NVP), and the influence factors of the grafting degree was preliminarily studied. The structure of the grafted copolymer was characterized by the Fourier-transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA), and the solution viscosity properties of the grafted copolymer in low grafting rate were studied by rheometer. The results show that the grafting rate increases with absorbed dose and gradually achieve to the balance. The grafting rate reaches maximum when the xanthan gum concentration is 10 g/L or the mass ratio is 10:1 meanwhile the other two factors are in a certain experimental value range. FT-IR figure shows that the grafting reaction occurs in NVP vinyl part and lactam structure is retained. Thermo-gravimetric analysis shows that XG-g-NVP enhanced thermal stability of xanthan gum. The properties of XG-g-NVP solution show that grafting to enhance the performance of resisting high temperature and shear strength. (authors)

  5. 60Coγ射线半身照射对非照射区域骨髓造血组织基质细胞衍生因子1表达的影响%Influences of 60Coγray irradiation on expression stromal cell derived factor-1 in bone marrow hematopoietic tissue of non-irradiation area in left-half-body ionizing irradiated mice

    Institute of Scientific and Technical Information of China (English)

    高作文; 杨龙; 陈乐如; 娄金书; 张国强; 李开信; 程天民

    2013-01-01

    Objective To invesligale the mouse bone marrow hemalopoielic functions in non-irradiation area after irradiated by way of left-half- body. Methods The 6-8-week male Kunming strain mice were randomly divided into normal control( NC) , total-body-irradiated( TBI) , left-half-body-irradiated( LHBI) , and total-body-shield-irradia-ted( TBSI) groups. Left-half-body-irradiated group was treated with two pieces of 5 cm x 8 cm x 16 cm overlapped lead bricks shielding right-side body and irradiated with 8. 0 Gy60Coγ-ray. The leukocyte in peripheral blood and the number of bone marrow hematopoietic cells( BMHCs) were studied, the concentration of SOD, MDA in mouse serum were measured, and the expression SDF-1 in bone marrow hematopoietic tissues were observed by the Western blotting method and laser scanning confocal microscope combined with immunohistochemistry. Results In the left-half-body irradiated condition, the leucocyte in peripheral blood and the BMHCs were diminished, the concentration of MDA was increased and the SOD was decreased in the mouse serum remarkably ( compared with NC, P <0. 01) ; In non-irradiation area, the SDF-1-positive cells and the expression SDF-1 in bone marrow hematopoietic tissues were reduced significantly. Conclusion Our study suggested that the local irradiation resulted in the decrease of SDF-1-positive cells and the decline expression SDF-1 in bone marrow hematopoietic tissues in non-irradiation area, and the increase of reactive oxygen or free radicals might play an important role in the abnormal expression of SDF-1 in BMHT and the injury of hematopoietic microenvironment.%目的 探讨局部电离辐射对小鼠非照射区域骨髓造血组织基质细胞衍生因子-1(SDF-1)表达的影响.方法 将6~8周龄雄性昆明小鼠随机分为健康对照组、全身照射组、全身屏蔽照射组以及左半身照射组4组,用铅屏蔽建立半身照射模型,以8.0 Gy 60Co γ射线照射,观察小鼠外周血白细胞和骨髓有核

  6. Application of gamma irradiation technique for the preservation of propolis

    International Nuclear Information System (INIS)

    Irradiation has been recognized as an efficient method for the reduction of deteriorating and pathogenic microorganisms in foods. Propolis is a resinous product made by bees from material processed by the bee's own metabolism and resins from plants. The aim of this work was the application of gamma irradiation technique for the preservation of propolis, because of its efficiency in the reduction of the microbial load. The changes on the total flavonoids content, phenolic compounds and other characteristics required for the qualification and characterization of Brazilian propolis were also analysed. Propolis samples from Juiz de Fora region, Minas Gerais, were irradiated in a 60Co source, with doses from 0 to 10kGy for the microbiological analyses and 5.0, 7.0 and 10.0kGy for the physico-chemical analyses. The physico-chemical that have been made were: determination of total flavonoids content, semi-quantitative determination of phenolic compounds (artepelin-C, kempferol, chrysin, galangin and quercetin), dry matter analysis, humidity, ash content, mechanical mass and waxes. The ionizing radiation has shown to be efficient in the reduction of the microbial load. Total coliforms determination showed a great reduction with the dose of 3kGy and concerning mesophile aerobic bacteria a systematic reduction was observed, achieving values <10 UFC/g for the dose of 10kGy; similar results was obtained for molds and yeasts. Salmonella assays were negative for all samples. There was no significant alteration on total flavonoids contents nor on the composition of phenolic compounds as a consequence of radiation application at the assayed conditions. The complementary analyses of dry matter and humidity contents, ashes, mechanical mass and waxes did not shown changes after irradiation even with the maximum dose of 10kGy, remaining the results within the standards required by the Brazilian legislation. (author)

  7. Simulation of gamma irradiation system for a ballast water treatment

    International Nuclear Information System (INIS)

    Invasion by different kinds of ballast the water microorganisms is one of the most important marine environment problems around the world therefore preventing the invasion of these unwanted and harmful stowaways is one of the main strategies of responsible agencies. Some of these methods such as ocean exchange, heating, filtration, hydro cyclones, UV irradiation and chemical treatment, have various problems such as technical deficiency, high costs, lack of safety and environmental side effects. Materials and Methods: A novel system of treatment by Gamma irradiation is designed to irradiate the blast water uniformly and effectively. To determine the dose distribution as a function of distance from the irradiation source, the MCNP code was used. The systems used for source implant in this simulation were Paterson-Parker, Paris and Network systems. In each system, Sivert-integral and inverse square law were used in MATLAB program to determine the dose distribution. Results: Results of initial laboratory tests on offshore water samples of Siri Island indicated that the appropriate dose for deactivation of organisms of water samples is approximately one kGy. It has been demonstrated that the dose can be provided by twenty five 100,000 Ci line sources of '60Co in a triangle implant arranged in a 1*1*1 m3 cubic shape water pipe. In order to increase efficiency and radiation safety, water passed from two other coaxial and bigger cubes, after passing from the first cube. A one meter thick wall of concrete around the cubes was adequate to shield the system completely. Conclusion: The main advantages of this system such as high efficiency, safety, reliability, minimum environmental adverse effects, proves that this novel method not only can be used for ballast water treatment, but is also effective for drinking water purification

  8. Inactivation of mildew in rough rice and wheat by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jun, E-mail: jwang@zju.edu.c [Department of Biosystems Engineering, Zhejiang University, 268 Kaixuan Road, Hangzhou 310029 (China); Yu Yong [Department of Biosystems Engineering, Zhejiang University, 268 Kaixuan Road, Hangzhou 310029 (China)

    2010-06-15

    Rough rice and wheat were irradiated by gamma ray ({sup 60}Co) with different doses and the mildew inactivation efficacy was investigated after 0, 6 and 12 month storage. Five genera of mildew in rough rice and wheat were detected, including Alternaria, Fusarium, Aspergillus, Penicillium and Rhizopus. For Aspergillus, four genera of mold were detected, including Aspergillus Kawachii, Aspergillus glaucus, Aspergillus niger, Aspergillus flavus. Detection rates of the five genera of mildew and four genera of Aspergillus were all reduced with increasing dose after 0, 6 and 12 months storage. The detection rates of the other four genera of mildew had no significant change during storage.

  9. Investigations on fiberoptic behaviour during gamma irradiation

    Science.gov (United States)

    Siehs, J.

    1980-12-01

    The behavior of bulk glasses and fiber optics under gamma irradiation and two types of annealing processes (thermal and optical) were investigated. The samples were irradiated in the thermal column of the TRIGA Mark II reactor. The irradiation induced losses of transmission were measured in a dual beam spectrophotometer. The transmission was measured one hour after reactor shut-down. Thermal annealing was done at 300, 400 and 500 C. Photo bleaching was investigated with a quartz-lamp, an arc-lamp and an UV-laser light.

  10. Gamma-ray irradiation tests of CMOS sensors used in imaging techniques

    Directory of Open Access Journals (Sweden)

    Cappello Salvatore G.

    2014-01-01

    Full Text Available Technologically-enhanced electronic image sensors are used in various fields as diagnostic techniques in medicine or space applications. In the latter case the devices can be exposed to intense radiation fluxes over time which may impair the functioning of the same equipment. In this paper we report the results of gamma-ray irradiation tests on CMOS image sensors simulating the space radiation over a long time period. Gamma-ray irradiation tests were carried out by means of IGS-3 gamma irradiation facility of Palermo University, based on 60Co sources with different activities. To reduce the dose rate and realize a narrow gamma-ray beam, a lead-collimation system was purposely built. It permits to have dose rate values less than 10 mGy/s and to irradiate CMOS Image Sensors during operation. The total ionizing dose to CMOS image sensors was monitored in-situ, during irradiation, up to 1000 Gy and images were acquired every 25 Gy. At the end of the tests, the sensors continued to operate despite a background noise and some pixels were completely saturated. These effects, however, involve isolated pixels and therefore, should not affect the image quality.

  11. Use of gamma irradiation for prolonging shelf life of Garden pea (Pisum sativum L.)

    International Nuclear Information System (INIS)

    Garden pea pods of variety Arkel were irradiated with 5 doses of 60Co gamma rays ranging from 0.5-3 kGy and stored at ambient temperature up to 9 days along with control to study the effect of radiation in prolonging shelf life of pea pods and stabilizing its market demand. Physiological weight loss percentage decrease as the doses of gamma radiation increased. Minimum weight loss was noted in pods treated with 3 kGy gamma radiation as compared to control. Decay loss percent showed inverse relation with dose of gamma radiation. The minimum decay loss was recorded in 3 kGy and the organisms identified for decay loss were Alternaria and Cladosporium species of fungi. With regard to sugar content, pea pods irradiated with 1 kGy gamma rays recorded maximum sugar content. Pods irradiated with 0.5 kGy and 1 kGy gamma rays retained their green colour for a long period (up to 9th day of storage). Based on 9 point's hedonic scale the overall acceptability for appearance, taste and texture was observed in 1 kGy treatment. (author)

  12. The combined effect of the gamma radiations of 60 Co and different chemicals on the cells of the radicular vegetative tip of Allium sativum L

    International Nuclear Information System (INIS)

    The gamma ionizing radiations used alone in the treatment of Allium Sativum L. affected differently the cells belonging to the two zones of the root causing modifications of the cellular parameters which have been previously estimated. Data in the literature established that the damage of the interphasic nucleus of the cells determines the obstruction of the DNA synthesis and the delay of the cell mitosis. Sparrow, A. H., Miller, M. W. and Al-Rubeai confirmed the existence of a relationship between the nuclear volumes and the radiosensitivity of the different types of cells. The aim of this experiment was to counteract the harmful effect of gamma radiations at cellular level with the help of combined treatments, namely, the gamma radiations associated with different chemicals having radioprotective effects. The biological significance of the obtained values was established by statistical calculations with the help of the Student (t) test. The values of the estimated cellular parameters, NV, ICV, CV, NCR showed that, although there were certain fluctuations, their values were not always significant. (author)

  13. Study of the action of {sup 60}Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp; Estudo da acao da radiacao gama de {sup 60}Co sobre Salmonella poona, Escherichia coli e Alicyclobacillus acidoterrestris em polpa de manga congelada

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Marco Antonio dos Santos

    2009-07-01

    The application of non-thermal treatments has proven effective in inhibiting bacteria such as Salmonella and Escherichia coli. Mango is a fruit of national consumption with a great exportation potential. Meanwhile, outbreaks of food borne disease related to mango consumption caused mistrust on the degree of food security offered by the product. The objective of this work was to establish the radioresistance of bacteria Escherichia coli, Salmonella Poona and Alicyclobacillus acidoterrestris on the mango pulp by the calculation of the D10 values and to know the radiation effect on the sensory characteristics of the fruit pulp. The microbiological profile of frozen mango pulp available at the local market was also established using conventional methods of plating and Most Probable Number (MPN). The pulps experimentally inoculated with the bacteria listed above were irradiated with doses of 0, 1, 2, 3, 4 and 5kGy in a {sup 60}Co source. The sensory analysis was performed using a dose of 5 kGy, using the triangular test and the test of acceptance with hedonic scale. The results of this study show that the quality of mango pulp sell in the local market is not satisfactory in accordance with the standards established by the Brazilian law and the literature, showing the need of using other tools to achieve acceptable levels of quality. The D10 values obtained are in the range of 1.01 and 1.09kGy for E. coli ATCC 8739, 0.60 and 0.98kGy for S. poona and 0.72 e 0.88kGy for A. acidoterrestris respectively. The triangular test showed that a 5kGy radiation dose changed the sensory characteristics of mango pulp. Nevertheless, sensory analysis of a food product prepared with the irradiated pulp obtained good acceptance in the attributes of global appearance, flavor and aroma. (author)

  14. Study of the action of {sup 60}Co gamma radiation on Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris in mango pulp;Estudo da acao da radiacao gama de {sup 60}Co sobre Salmonella poona, Escherichia coli and Alicyclobacillus acidoterrestris em polpa de manga congelada

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Marco Antonio dos Santos

    2009-07-01

    The application of non-thermal treatments has proven effective in inhibiting bacteria such as Salmonella and Escherichia coli. Mango is a fruit of national consumption with a great exportation potential. Meanwhile, outbreaks of foodborne disease related to mango consumption caused mistrust on the degree of food security offered by the product. The objective of this work was to establish the radioresistance of bacteria Escherichia coli, Salmonella Poona and Alicyclobacillus acidoterrestris on the mango pulp by the calculation of the D10 values and to know the radiation effect on the sensory characteristics of the fruit pulp. The microbiological profile of frozen mango pulp available at the local market was also established using conventional methods of plating and Most Probable Number (MPN). The pulps experimentally inoculated with the bacteria listed above were irradiated with doses of 0, 1, 2, 3, 4 and 5 kGy in a {sup 60}Co source. The sensory analysis was performed using a dose of 5 kGy, using the triangular test and the test of acceptance with hedonic scale. The results of this study show that the quality of mango pulp sell in the local market is not satisfactory in accordance with the standards established by the Brazilian law and the literature, showing the need of using other tools to achieve acceptable levels of quality. The D10 values obtained are in the range of 1.01 and 1.09 kGy for E. coli ATCC 8739, 0.60 and 0.98 kGy for S. poona and 0.72 and 0.88 kGy for A. acidoterrestris respectively. The triangular test showed that a 5 kGy radiation dose changed the sensory characteristics of mango pulp. Nevertheless, sensory analysis of a food product prepared with the irradiated pulp obtained good acceptance in the attributes of global appearance, flavor and aroma. (author)

  15. Protective effect of poly ({alpha}-L-glutamate) against UV and {gamma}-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu E-mail: mfuruta@riast.osakafu-u.ac.jp; Huy, Nguyen Quang; Tsuchiya, Akihito; Nakatsuka, Hiroshige; Hayashi, Toshio

    2004-10-01

    We occasionally found that poly ({alpha}-L-glutamate) showed a superior protective effect on enzymes against UV and {sup 60}Co-{gamma} irradiation. We selected papain and {alpha}-amylase as a model enzyme and irradiated the aqueous solution (10 mg/ml) of each enzyme with UV and {sup 60}Co-{gamma} rays in the presence of poly ({alpha}-L-glutamate) ({alpha}-PGA), poly (glucosyl oxyethyl methacrylate (GEMA)), and glucose (1.25% w/v each). The mixture of the three compounds has a significant protective effect on the activity of papain solution showing 40% of remaining activity twice as much as the control containing no additive at the dose of 15 kGy. Among them, {alpha}-PGA showed the highest protecting effect on the both papain and {alpha}-amylase even after 10-kGy irradiation at which 50% of the activity was retained. {alpha}-PGA also showed significant protective activity on {alpha}-amylase against UV both in solution and under dried state.

  16. Use of gamma irradiation for wheat sterilization as a media for cultivation of mushrooms' spawn

    International Nuclear Information System (INIS)

    In recent years, respect to mushrooms, nutritious value cultivation and culture of this valuable crop has increased in our country. Since, today the nuclear techniques for preserving and improving the quality of agricultural products and foods are being the core of consideration and these techniques are being vastly utilized, therefore we can use these techniques to eliminate some of the existing problems which appear during processing of mushrooms. In this research the possibility of using 60 Co gamma irradiation to sterilize the wheat as a medium culture of mushroom mycelia was examined and during several experiments we obtained the suitable gamma irradiation dose rate (10000 Gy) and then, we made a comparison between two methods of wheat sterilization i.e. by the means of; l: autoclave and 2: gamma irradiation with respect to the quality and race of 'Pleuroturs Sajor Caju' mushrooms, mycelium growth. According to the results, at the early stage of experiments no noticeable difference between autoclave and irradiated samples was observed but gradually it was noted that on irradiated culture bed the mycelium growth was infinitely better than those on autoclave wheat. Thus in irradiated seeds grain, since the grain wheat was remained sound, the my celia were grown regularly

  17. Gamma irradiation of peanut (Arachis hypogaea L.)

    International Nuclear Information System (INIS)

    This study was conducted to determine some effects of gamma radiation on peanut (Arachis hypogaea L.). The biological parameters used to evaluate these effects were: % emergence of irradiated seeds, % survival of plants, growth rate, chlorophyll mutations, morphological changes and yield potential. Seeds were irradiated with dose levels of 2.5, 5, 10, 15, 20, 25, 30 and 40 KK per hour of gamma radiation from a Co-60 source. In general, % of emergence and survival in the M1 gene ration decreased with increasing doses of gamma radiation. Morphological changes induced by gamma radiation in the M1 generation of peanut were: leaf flecks, thickened leaves, red purple seeds and red colored seed coat. Generally, frequency of these morphological changes increased with increasing doses of gamma radiation. Protein and fat contents were increased by 2.8% to 1.5% respectively, while starch content decreased with 2.6% in the M2. On the basis of the results obtained, gamma radiation is an effective mutagenic agent in inducing various morphological and genetic changes in peanut

  18. Evaluation of gamma and neutron irradiation effects on the properties of mica film capacitors

    Indian Academy of Sciences (India)

    Rajesh Roy; Arun Pandya

    2005-12-01

    We present an investigation of gamma and neutron radiation effects on mica film capacitors from an electrical point of view. We have studied quantitatively the effects of gamma and neutron irradiation on mica film capacitors of thickness, 20 and 40 m (0.7874 and 1.5748 mil) with two different areas, 01 and 04 cm2. The capacitance has been measured at room temperature in the frequency range 100 Hz–10 MHz. Negligible change in the capacitance due to high gamma dose of 60Co, 15 kGy at dose rate 0.25 kGy/h, has been observed. However, appreciable change in the capacitance has been observed due to low doses of fast neutrons (cumulative dose, 115 cGy) with flux ∼ 9.925 × 107 neutrons/cm2 h from 252Cf neutron source of fluence, 2.5 × 107 neutrons/s. We have also observed that the impact of gamma and neutron irradiation is more at frequencies higher than 10 kHz. These results show that the mica capacitors do not show any radiation response below 10 kHz. The study shows the radiation response of mica film capacitors to gamma and fast neutron radiations. Mica capacitors show low gamma radiation response in comparison to fast neutron radiation, because a total dose of kGy order has been given by gamma source and only few cGy dose has been given by fast neutron source.

  19. The aging process of optical couplers by gamma irradiation

    Science.gov (United States)

    Bednarek, Lukas; Marcinka, Ondrej; Perecar, Frantisek; Papes, Martin; Hajek, Lukas; Nedoma, Jan; Vasinek, Vladimir

    2015-08-01

    Scientists have recently discovered that the ageing process of optical elements is faster than it was originally anticipated. It is mostly due to the multiple increases of the optical power in optical components, the introduction of wavelength division multiplexers and, overall, the increased flow of traffic in optical communications. This article examines the ageing process of optical couplers and it focuses on their performance parameters. It describes the measurement procedure followed by the evaluation of the measurement results. To accelerate the ageing process, gamma irradiation from 60Co was used. The results of the measurements of the optical coupler with one input and eight outputs (1:8) were summarized. The results gained by measuring of the optical coupler with one input and four outputs (1:4) as well as of the optical couplers with one input and two outputs (1:2) with different split ratios were also processed. The optical powers were measured on the input and the outputs of each branch of each optical coupler at the wavelengths of 1310 nm and 1550 nm. The parameters of the optical couplers were subsequently calculated according to the appropriate formulas. These parameters were the insertion loss of the individual branches, split ratio, total losses, homogeneity of the losses and directionalities alias cross-talk between the individual output branches. The gathered data were summarized before and after the first irradiation when the configuration of the couplers was 1:8 and 1:4. The data were summarized after the third irradiation when the configuration of the couplers was 1:2.

  20. 60Co γ射线辐照预处理对甘薯热风干燥特性的影响%INFLUENCE OF 60Co γ IRRADIATION PRE-TREATMENT ON CHARACTERISTICS OF HOT AIR DRYING SWEET POTATO SLICES

    Institute of Scientific and Technical Information of China (English)

    江宁; 刘春泉; 李大婧; 刘霞; 严启梅

    2012-01-01

    The influences of irradiation, hot air temperature and thicknesses of the slices on the characters of dehydration and surface temperature of 60Co γ-rays irradiated sweet potato were investigated. Meanwhile, microscopic observation and determination of water activity of irradiated sweet potato were conducted. The results show that the drying rate and the surface temperature rised with the increasing of irradiation dose. When the dry basis moisture content was 150% , the drying rate of the samples were 1.92, 1.97, 2.05, 2.28, 3.12%/min while the irradiation dose were 0, 2, 5, 8, 10kGy, and the surface temperature were 48.5℃ , 46.3℃ , 44.5℃, 42.2℃, 41.5℃ , respectively. With higher air temperature and thinner of the sweet potato slices, the dehydration of the irradiated sweet potato slices were faster. The drying speed of sweet potato slices at 85℃ was 170min faster than that of 65℃. The drying speed of 7mm sweet potato slices was 228min faster than that of 3mm sample. The cell wall and the vacuole of the sweet potato slices were broken after irradiation, and its water activity increased with the inorease is radiation dose. The water activity of the irradiated samples were 0. 92, 0. 945, 0. 958, 0. 969, 0. 979 with the irradiation doses of 0, 2, 5, 8, 10kGy, respectively. The hot air drying rate, surface temperature and water activity of sweet potato are significantly impacted by irradiation. The conclusion provids a theoretical foundation for further processing techonology of combined radiation and hot air drying sweet potato.%采用60Coγ射线对甘薯进行辐照预处理,考察辐照、热风温度和切片厚度对其干燥特性和表面温度的影响,同时对不同剂量辐照的甘薯样品进行了显微观察和水分活度测定。结果表明,甘薯的干燥速率和表面温度随着辐照剂量的升高而升高。当干基含水率为150%时,辐照剂量为0、2、5、8和10kGy的样品干燥速率分别为1.92、1.97、2.05、2.28和3

  1. Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

    International Nuclear Information System (INIS)

    The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes 60Co as radiation source. The developed work provides an accurate control and data acquisition for the application of good manufacturing practices during all phases of an irradiation process, required by the standards of ANVISA, technical ISO and IAEA recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The automatic data process acquisition using wireless ZigBee technology, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN-SP all the development was performed to be applied in irradiators' facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

  2. Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Jose R., E-mail: joseroberto.soares@mackenzie.br [Universidade Presbiteriana Mackenzie. Escola de Engenharia. Sao Paulo, SP (Brazil); Rela, Paulo R.; Costa, Fabio E., E-mail: prela@ipen.br, E-mail: fecosta@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes {sup 60}Co as radiation source. The developed work provides an accurate control and data acquisition for the application of good manufacturing practices during all phases of an irradiation process, required by the standards of ANVISA, technical ISO and IAEA recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The automatic data process acquisition using wireless ZigBee technology, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN-SP all the development was performed to be applied in irradiators' facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

  3. Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

    International Nuclear Information System (INIS)

    The sterilization of medical care products using ionizing radiation is a consolidated technique. In Brazil there are in operation gamma irradiators with capacity between 0.37 PBq (10kCi) 185 PBq (5 MCi) using radioisotopes 60Co as radiation source. The developed work provides an accurate control and a data acquisition for the application of Good Manufacturing Practices during all phases of an irradiation process, required by the standards of ANVISA, ISO and IAEA technical recommendations for the treatment of foods and medical products. All the steps involved in the irradiation treatment are mapped into process flow (work flow), where each agent (participant) has its systematized tasks. The data acquisition process, monitoring and control, are based on a set of tools (free software licenses) integrated by a network of efficient communication, including the use of Web resources. Using the Gamma Irradiator Multipurpose IPEN/CNEN/USP all the development was performed to be applied in irradiators facilities operating in industrial scale. The system enables a complete traceability of the process, in real time, for any participant and also the storage of the corresponding records to be audited. (author)

  4. Research of Effect of 60Co γ-ray Irradiation on Cell Cycle of SMMC, 7721 Tumor Cell with Flow Cytometery

    Institute of Scientific and Technical Information of China (English)

    DangBingrong; MaQiufeng; GaoQingxiang; LiWenjian; HaoJifang; XieYi; GuoChuanling

    2003-01-01

    The resultsMost researchof cell cycle play an important role in resear, ching tumor occurrence, development and treatment. results show that malignant grade and pharmic sensitivity of tumor are relative to cell cycle. The sensitivity of medications is different to different phases of cell cycle of tumor. In general, the cell of M are more sensitivity. On the side, different medications have different action in different cell cycle. The irradiation can change cell cycle proccss and can induce the pattern of changes in cell cycle. For cxamplc, G1 arrest, G2 arrest and S arrest. So, thc research rcsults of tumor cell cycle in different irradiation have not only biological means but also realistic means for selecting chemical therapy medication after radiotherapy.

  5. Effect of 60CO radiation processing in mate (Ilex paraguariensis)

    International Nuclear Information System (INIS)

    The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co at doses 0, 3, 5, 7 and 10kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and

  6. Effect of 60Co radiation processing in mate (Ilex paraguariensis)

    International Nuclear Information System (INIS)

    The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and

  7. Laboratory longevity and competitiveness of Dacus ciliatus Loew (Diptera: Tephritidae) following sub-sterilizing gamma irradiation.

    Science.gov (United States)

    Nemny-Lavy, E; Nestel, D; Rempoulakis, P

    2016-06-01

    The effect of a sub-sterilizing gamma radiation dose on Dacus ciliatus adults was investigated to assess the suitability of the sterile insect technique (SIT) as an alternative method to control this pest. Late pupae (48 h prior to adult emergence) from a laboratory strain were irradiated with 120 Gy of gamma rays emitted by a 60Co source. Following adult emergence, the mortality of irradiated and non-irradiated cohorts was recorded. Over a period of 50 days after emergence, no significant negative effects of irradiation upon the longevity of male or female laboratory flies were observed. A laboratory competitiveness study (Fried test), using irradiated laboratory and wild males at a ratio of 3:1 was conducted to assess the ability of irradiated males to reduce the egg hatch rates of a wild population. The overall competitiveness was found to be ca. 0.32, suggesting a reduced, but satisfactory, quality of irradiated laboratory as compared with wild males. Based on the above findings, we calculated and proposed effective male release ratios for field application of SIT against D. ciliatus. PMID:26898660

  8. Toxoplasma gondii vs ionizing radiation: cell and humoral immunity in spleen and gut of isogenic mice immunized with 60Co irradiated tachyzoites

    International Nuclear Information System (INIS)

    We are developing a vaccine for toxoplasmosis, using ionizing radiation as a tool. Here we analyzed the production of systemic and intestinal immunity, with protection studies, in several strains of inbred mice, by oral or parenteral route, using 255 Gy irradiated tachyzoites of T. gondii RH strain, with challenge with cysts of ME- 49 strain. C57Bl/6j, BALB/c and C57Bl/6j IFN-γ-/- mice were immunized with 107 irradiated tachyzoites, be parenteral or oral route. Those preparations, both by parenteral or oral routes, induced the production of specific IgG, mainly of the lgG2b subclass, and IgA immunoglobulins in serum, , as determined by ELISA. IgM production was negligible. Parenteral immunized mice showed higher IgG avidity maturation, as compared to oral immunized mice. Fecal excretion of IgG, IgA and IgM was detected in stools of immunized animals, more intense in oral immunized mice. In cellular immunity studies, induced by antigen, with detection of cytokine production by quantitative real-time PCR, there are a great production of IFN-y by spleen cells, with lower levels in Peyer patches cells, where there are a greater IL-2 production. Challenge studies in immunized mice demonstrated protection to infection in all used schedules, greater in BALB/c mice. C57Bl/6j IFN-γ -/- mice, when immunized, showed no signs of disease and produced similar or greater levels of antibodies than wild type mice. They also excreted S-lgA and S-IgM in stools, but with low numbers of brain cysts in parenteral immunized mice, despite similar mortality. Our data points to a fair possibility of use of those irradiated parasites as an oral vaccine, devised to use for veterinary or wild felines vaccination, reducing the production of oocysts by those hosts and interrupting the chain transmission of human toxoplasmosis. (author)

  9. Cytotoxicity of mycotoxins after gamma irradiation

    OpenAIRE

    Calado, Thalita; Verde, S. Cabo; Abrunhosa, Luís; Fernández-Cruz, M.; Venâncio, Armando

    2015-01-01

    Due to the high toxicity of mycotoxins, many methods have been used to reduce or eliminate them from food and feed. Gamma radiation is one technique that has been investigated with some promising results in the degradation of mycotoxins from food commodities. The aims of this study were (i) to clarify the effect of gamma irradiation on aflatoxin B1 (AFB1), aflatoxin B2, aflatoxin G1, aflatoxin G2 and ochratoxin A (OTA); (ii) to evaluate the effect of the presence of water du...

  10. The use of gamma irradiation in vivo and combined use in vitro culture to select mutant clones in sweet potato

    International Nuclear Information System (INIS)

    Some clonal lines resistant to black rot and to nematodes were successfully obtained in the vegetative progenies of sweet potato cuttings from a susceptible variety irradiated by 60Co gamma rays. The variation or mutant characters were transmitted to their vegetative progenies, retaining the favourable genetic background of the original varieties. The mutant clones can be released as varieties for production or as germplasm for future breeding use. In some experiments, gamma irradiation was combined with in vitro culture. The appropriate experimental conditions, such as radiation dose, light intensity and duration, culture medium and temperature were clarified. Solid mutants of skin color could be obtained in a relatively short time. The results indicated that in vitro culture could reduce chimerism or at least shorten the time required to obtain solid mutant clones after the gamma irradiation. Some techniques need to be improved further. (author). 11 refs, 16 tabs

  11. Effect of gamma-irradiation on disinfectant, 1

    International Nuclear Information System (INIS)

    The effect of 60Coirradiation on the antibacterial activity of chlorhexidine hydrochloride was examined and the following results were obtained. 1. The radioresistance of B. pumilus ATCC 27142 spore suspended in the solution of chlorhexidine hydrochloride was apparently higher than that suspended in distilled water. 2. The antibacterial activity of chlorhexidine hydrochloride irradiated in wet state decreased with an increase of irradiation dose, but that in dry state did not decrease. Upon irradiating chlorhexidine hydrochloride adsorbed on cellulose product, the antibacterial acticity showed a similar tendency. (auth.)

  12. Sensitivity of rice varieties to gamma irradiation

    OpenAIRE

    R.Sasikala and R.Kalaiyarasi

    2010-01-01

    Six promising rice varieties viz., CO 43, CO 47, CO 48, CO 49, ADT 43 and Improved White Ponni were treated withgamma irradiation with doses of 100Gy, 200Gy, 250Gy, 300Gy and 350Gy of gamma rays in order to study effect of gammairradiation in seed germination of rice varieties and study the root and shoot length variation. Treated seeds were sownseparately in germination paper and nursery with the two replications. The germination percentage was decreased aftergamma irradiation. But the decre...

  13. Hippophae leaf extract (SBL-1) countered radiation induced dysbiosis in jejunum of total body 60Cobalt gamma - irradiated mice

    International Nuclear Information System (INIS)

    Single dose of SBL-1 administered at the rate 30 mg/kg body weight (b.w.) 30 min prior to whole body 60Co-gamma-irradiation at lethal dose (10 Gy), rendered >90% survival in comparison to zero survival in the non-SBL-1 treated 60Co-gamma-irradiated (10 Gy) mice population (J Herbs Spices Med Plants, 2009; 15(2): 203-215). Present study investigated the effect of SBL-1 on jejunal microbiota in lethally irradiated mice. Study was performed with inbred Swiss albino Strain 'A' male mice (age 9 weeks) weighing 28±2 g. The animals were maintained under controlled environment at 26±2℃; 12 h light/dark cycle and offered standard animal food (Golden feed, Delhi) as well as tap water ad libitum. Metagenomic DNA was extracted, purified and quantified from jejunum of the mice. Universal primers (27f and 1492r) were used to amplify the 16S rRNA DNA from the metagenomic DNA. Amplicons were sequenced, vector contamination and chimeras were removed. The sequences (GenBank Accession No: KF681283 to KF681351) were taxonomically classified by using Sequence Match program, Ribosomal Database Project as well as by nucleotide-BLAST (E-value: 10, database: 16S rRNA gene sequences, Bacteria and Archea). Phylogenetic Tree was prepared using MEGA 5.2 package, using maximum likelihood algorithm after sequence alignment by MUSCLE. Thermus aquaticus was used as out-group to construct rooted tree. Branch stability was assessed by bootstrap analysis. Untreated animals and the animals treated with SBL-1 had 100% Lactobacillus; 60Co gamma-irradiated animals had 55% Cohaesibacter (Alphaproteobacteria); 27% Mycoplasma (Tenericutes) and only 18% Lactobacillus; animals treated with SBL-1 prior to irradiation had 89% Lactobacillus and 11% Clostridium. This study demonstrated that treatment with SBL-1 at radioprotective doses before total body irradiation with lethal dose (10 Gy) countered the jejunal dysbiosis. (author)

  14. Gamma irradiation in a saturated tuff environment

    International Nuclear Information System (INIS)

    The influence of gamma irradiation on the reaction of actinide doped SRL 165 and PNL 76-68 glasses in a saturated tuff environment has been studied in a series of tests lasting up to 56 days. The reaction, and subsequent actinide release, of both glasses depends on the dynamic interaction between radiolysis effects which cause the solution pH to become more acidic and glass reaction which drives the pH more basic. The use of large gamma irradiation dose rates to accelerate reactions that would occur in an actual repository radiation field may affect this dynamic balance by unduly influencing the mechanism of the glass-water reaction. Comparisons are made between the present results and data obtained by reacting the same or similar glasses using MCC-1 and NNWSI rock cup procedures. 11 references, 3 figures

  15. Evaluation of gamma irradiation of teas

    Energy Technology Data Exchange (ETDEWEB)

    Gerolis, Luanai G.L.; Lameiras, Fernando S.; Menezes, Maria A.B.C.; Leal, Alexandre S., E-mail: luanaigraz@yahoo.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Krambrock, Klaus, E-mail: klaus@fisica.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisica. Lab. de Ressonancia Paramagnetica Eletronica

    2013-07-01

    There is a growing interest in the determination of non-essential traces elements in agroindustrial products. The continuous ingestion and accumulation in the organism of such elements, that may be toxic, can cause hazards to the human health in the long term. Reliable analytical techniques are necessary to monitor such products, including teas. In this work, the neutron activation technique is being employed to determine the trace elements in teas, due to its high sensibility and the possibility to perform a multi-elementary analysis. The gamma irradiation of teas is also being studied, because the shelf life can be extended and no chemical product is added to the teas. There is a concern related to the formation of free radicals in the teas, which is being accessed with electronic paramagnetic resonance. The results of the gamma irradiation up to 20 kGy of Camelia sinensis, Ilex paraguariensis, and Matricaria recutita are presented. (author)

  16. Decoloration Kinetics of Waste Cooking Oil by 60Co γ-ray/H2O2

    Science.gov (United States)

    Xiang, Yulin; Xiang, Yuxiu; Wang, Lipeng

    2016-03-01

    In order to decolorize, waste cooking oil, a dark red close to black solution from homes and restaurants, was subjected to 60Co γ-ray/H2O2 treatment. By virtue of UV/Vis spectrophotometric method, the influence of Gamma irradiation to decoloration kinetics and rate constants of the waste cooking oil in the presence of H2O2 was researched. In addition, the influence of different factors such as H2O2 concentration and irradiation dose on the decoloration rate of waste cooking oil was investigated. Results indicated that the decoloration kinetics of waste cooking oil conformed to the first-order reaction. The decoloration rate increased with the increase of irradiation dose and H2O2 concentration. Saponification analysis and sensory evaluation showed that the sample by 60Co γ-ray/H2O2 treatment presented better saponification performance and sensory score. Furthermore, according to cost estimate, the cost of the 60Co γ-ray/H2O2 was lower and more feasible than the H2O2 alone for decoloration of waste cooking oil.

  17. ESR identification of gamma-irradiated albendazole

    Science.gov (United States)

    Çolak, Seyda

    2010-01-01

    The use of ionizing radiation for sterilization of pharmaceuticals is a well-established technology. In the present work, the spectroscopic and kinetic features of the radicals induced in gamma-irradiated solid albendazole samples is investigated at different temperatures in the dose range of 3-34 kGy by electron spin resonance (ESR) spectroscopy. Irradiation with gamma radiation produced two different radical species in albendazole. They were fairly stable at room temperature but relatively unstable above room temperature, giving rise to an unresolved ESR spectrum consisting of three resonance peaks centered at g=2.0057. Decay activation energies of the contributing radical species were calculated to be 47.8 (±13.5) and 50.5 (±9.7) kJ/mol using the signal intensity decay data derived from annealing studies performed at high temperatures. A linear function of the applied dose was found to best describe the experimental dose-response data. Albendazole does not present the characteristics of good dosimetric materials. However, the discrimination of irradiated albendazole from its unirradiated form was possible even 6 months after storage in normal conditions. Based on these findings, it is concluded that albendazole and albendazole-containing drugs can be safely sterilized by gamma radiation and that ESR spectroscopy could be successfully used as a potential technique for monitoring their radiosterilization.

  18. Gamma irradiator dose mapping: a Monte Carlo simulation and experimental measurements

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Rogerio R.; Ribeiro, Mariana A.; Grynberg, Suely E.; Ferreira, Andrea V.; Meira-Belo, Luiz Claudio, E-mail: rrr@cdtn.b, E-mail: marianaalmeida@ufmg.b, E-mail: seg@cdtn.b, E-mail: avf@cdtn.b, E-mail: lcmb@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Sousa, Romulo V.; Sebastiao, Rita de C.O., E-mail: romuloverdolin@yahoo.com.b, E-mail: ritacos@ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Inst. de Ciencias Exatas. Dept. de Quimica

    2009-07-01

    Gamma irradiator facilities can be used in a wide range of applications such as biological and chemical researches, food treatment and sterilization of medical devices and products. Dose mapping must be performed in these equipment in order to establish plant operational parameters, as dose uniformity, source utilization efficiency and maximum and minimum dose positions. The isodoses curves are generally measured using dosimeters distributed throughout the device, and this procedure often consume a large amount of dosimeters, irradiation time and manpower. However, a detailed curve doses identification of the irradiation facility can be performed using Monte Carlo simulation, which reduces significantly the monitoring with dosimeters. The present work evaluates the absorbed dose in the CDTN/CNEN Gammacell Irradiation Facility, using the Monte Carlo N-particles (MCNP) code. The Gammacell 220, serial number 39, was produced by Atomic Energy of Canada Limited and was loaded with sources of {sup 60}Co. Dose measurements using TLD and Fricke dosimeters were also performed to validate the calculations. The good agreement of the results shows that Monte Carlo simulations can be used as a predictive tool of irradiation planning for the CDTN/CNEN Gamma Cell Irradiator. (author)

  19. Inactivation of RNA viruses by gamma irradiation

    International Nuclear Information System (INIS)

    Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD·MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D10 values, which are the dose necessary to decimally reduce infectivity, ranged from 1.5 to 3.4 kGy under frozen condition at dry-ice temperature, and they increased to 2.6 to 5.0 kGy under frozen condition at dry-ice temperature. Serum neutralzing antibody titer of Infectious Bovine Rhinotracheitis (IBR) was not adversely changed by the exposure to 36 kGy of gamma-rays under frozen condition. Analysis of electrophoresis patterns of the bovine serum also reveales that the serum proteins were not remarkably affected, even when exposed to 36 kGy of gamma radiation under frozen condition. The results suggested that gamma irradiation under frozen condition is an effective means for inactivating both DNA and RNA viruses without adversely affecting serum proteins and neutralizing antibody titer. (author)

  20. Stability of {gamma}-Irradiated Carmine

    Energy Technology Data Exchange (ETDEWEB)

    Cosentino, Helio M.; Del Mastro, Nelida L. [IPEN-CNEN/SP, Sao Paulo, SP (Brazil). Center of Radiation Technology; Fontenele, Rinaldo S. [Mackenzie Presbiterian Univ. Barueri, SP (Brazil)

    2005-07-01

    Carmine is a dye used mainly for coloring food products and galenicals but also in inks. As food irradiation is becoming a regular treatment for food preservation, it is desirable to have a proper knowledge about the radiation sensitivity of additives that can be included in the food formula. The aim of this work was to establish the radiation stability of carmine against Co-60 gamma radiation. Samples of 50% pure carmine powder as well as 50%, 10% and 5% aqueous solutions were irradiated in a Gammacell 220, dose rate of about 5.2kGy/h, with doses of 0, 1, 2, 4, 8, 16 and 32kGy. Spectrophotometric readings at 494{eta}m show a slight decrease of the absorbance as a function of dose: Samples irradiated with 4 and 32kGy retained 95% and 90% of absorbance of the unirradiated samples respectively. These results indicate a rather good stability of carmine against {gamma}-irradiation.

  1. Effects of gamma irradiation on deteriorated paper

    Science.gov (United States)

    Bicchieri, Marina; Monti, Michela; Piantanida, Giovanna; Sodo, Armida

    2016-08-01

    Even though gamma radiation application, also at the minimum dosage required for disinfection, causes depolymerization and degradation of the paper substrate, recently published papers seemed, instead, to suggest that γ-rays application could be envisaged in some conditions for Cultural Heritage original documents and books. In some of the published papers, the possible application of γ-rays was evaluated mainly by using mechanical tests that scarcely reflect the chemical modifications induced in the cellulosic support. In the present article the effect of low dosage γ-irradiation on cellulosic substrates was studied and monitored applying different techniques: colorimetry, spectroscopic measurements, carbonyl content and average viscometric degree of polymerization. Two different papers were investigated, a non-sized, non-filled cotton paper, and a commercial permanent paper. To simulate a real deteriorated document, which could need γ-rays irradiation, some samples were submitted to a hydrolysis treatment. We developed a treatment based on the exposition of paper to hydrochloric acid vapors, avoiding any contact of the samples with water. This method induces a degradation similar to that observed on original documents. The samples were then irradiated with 3 kGy γ-rays at a 5258 Gy/h rate. The aforementioned analyses were performed on the samples just irradiated and after artificial ageing. All tests showed negative effects of gamma irradiation on paper. Non-irradiated paper preserves better its appearance and chemical properties both in the short term and after ageing, while the irradiated samples show appreciable color change and higher oxidation extent. Since the Istituto centrale restauro e conservazione patrimonio archivistico e librario is responsible for the choice of all restoration treatments that could be applied on library and archival materials under the protection of the Italian State (http://www.icpal.beniculturali.it/allegati/DM-7

  2. Effect of gamma-ray and electron irradiation on the response of solid-state track detectors

    International Nuclear Information System (INIS)

    Specimens of muscovite mica were first exposed to fission fragments and then to various gamma-ray fields from a 60Co source ranging from 1.9 x 103 to 1.6 x 104 Mrad dose. The results show that the average etched width of fission-fragment tracks decreases with increasing gamma-ray dose. Shallow pits were observed in etched specimens when the gamma-ray dose exceeded 5 x 103 Mrad. Numerous shallow etch pits caused by the gamma-ray irradiation interfered with the observation of fission tracks in the specimens. No shallow etch pits were observed in the specimen annealed for 100 min at 6000C before the gamma-ray irradiation. Pre-annealing extends the ''safety limits'' of gamma background below which muscovite mica can be used to observe fission tracks without any gamma-ray interference. Gamma-ray and electron irradiation caused significant increase of the resistance to thermal decomposition of muscovite mica. The resistance increased markedly in the dose range from 5 x 103 to 8 x 103 Mrad. These phenomena suggest the use of mica to assess radiation doses of gamma rays and electrons up to several thousand megarads. (author)

  3. Five detector set-up for positron 1D-ACAR study of 60Co containing materials

    International Nuclear Information System (INIS)

    Design of the five detector set-up, for 1-Dimensional Angular Correlation of Annihilation Radiation (1-ACAR) study of 60Co-containing materials as well as test measurements are described. The equipment is based on simultaneous registration of a starting positron (by detection of gamma-photon with energy 1274 keV) and its annihilation with an electron in the studied material (by detection of two annihilation gamma photons with the energy 511 keV emitted mainly at the 180o-angle). Through this triple coincidence the distributing 60Co-contribution (gamma-photons with energy of 1.17 and 1.33 MeV) can be effectively separated from the annihilation spectra of irradiated reactor pressure vessel steel specimens. (author). 8 refs, 2 figs

  4. The Design of 60Co Container for Gamma Ray Radiography System%用于γ辐射成像系统的60Co源容器的设计

    Institute of Scientific and Technical Information of China (English)

    刘锡明; 吴志芳; 谈春明; 张颜民

    2012-01-01

    放射性同位素是辐射成像中常用的射线源,具有输出射线强度稳定、空间分布均匀恒定、操作维护简便、射线能量较单一、节能等优点,但是也存在防护和安全方面的问题,因此设计和开发功能完善、防护适当、安全可靠的放射源工作及储存容器十分重要.在60Co高精度工业CT系统中,依据相关国家标准,采用特殊的结构、屏蔽及安全设计,制作了60Co射线源的工作及储存容器.经实际测量,距容器表面5 cm和1m处空气吸收剂量率分别为170 μGy/h和5μGy/h.该容器功能完善、操作便利、结构坚固,具有多重安全设计,很好地满足了系统的检测要求,保障了人员的辐照安全.%Radioactive isotopes are frequently used in radiography systems as they have many advantages for imaging. For example, the intensity and spatial distnbuiion ol the gamma ray emitted are stable. The energy of gamma photons is fairly identical for most frequently used isotopes. The operation and maintenance are easy and require less energy. However, they are difficulties in their application in therms of radiation protection and safety. To solve this problem, it's very important to develop a fully functional, properly radiation protected, safe and reliable working and storage container for the radioactive source. In the 60Co high-precision industrial CT system, based on the corresponding national standards, the 60Co working and storage container was successfully developed by specific design of structure, shielding and security. The air absorbed dose rate was 170 μGy/h at 5 cm distance from the container surface and 5 μGy/h at 1 m distance according to actual measurements. The container has fall function- easy operation, robust construction and multiple safety measures. It meets requirements of the system and ensures operator's safety very well.

  5. Silicon/HfO2 interface: Effects of gamma irradiation

    Science.gov (United States)

    Maurya, Savita

    2016-05-01

    Quality of MOS devices is a strong function of substrate and oxide interface. In this work we have studied how gamma photon irradiation affects the interface of a 13 nm thick, atomic layer deposited hafnium dioxide deposited on silicon wafer. CV and GV measurements have been done for pristine and irradiated samples to quantify the effect of gamma photon irradiation. Gamma photon irradiation not only introduces positive charge in the oxide and at the interface of Si/HfO2 interface but also induce phase change of oxide layer. Maximum oxide capacitances are affected by gamma photon irradiation.

  6. Studies of structural modifications induced by. gamma. -irradiation in distearoylphosphatidylcholine liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Albertini, G.; Mariani, P.; Rustichelli, F.; Fanelli, E.; Guidoni, L.; Ianzini, F; Viti, V.; Masella, R.

    1987-07-01

    An investigation of the structural and thermodynamical modifications induced by ..gamma..-irradiation in model membranes is reported. Differential scanning calorimetry and X-ray diffraction were used to study different phases and associated transitions of distearoylphosphatidylcholine multilamellar liposomes after /sup 60/Co ..gamma..-irradiation. Changes were observed in the shape of calorimetric peaks and in corresponding phase transition temperatures. In particular a shoulder was observed at about 20 kGy. Three phases characteristic of lecithins with identical acyl chains were detected also for the highest radiation dose. Formation of lysolecithin and stearic acid upon phospholipid degradation was observed. Lysolecithin concentration increases as a function of irradiation dose; a saturation value is reached at 40 kGy. These results correlate quite well with those obtained for interlayer and interchain distances and for the width of the main phase transition calorimetric peak. At the highest dose (approx.80 kGy) cross-linked adjacent radicals and other molecular species are also formed. Appreciable differencies, and some similarities, in the behaviour of DSPC and DPPC liposomes under ..gamma..-irradiation were observed.

  7. Identification of gamma-irradiated papaya, melon and watermelon

    International Nuclear Information System (INIS)

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0 kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment

  8. Identification of gamma-irradiated papaya, melon and watermelon

    Energy Technology Data Exchange (ETDEWEB)

    Marin-Huachaca, N.S.; Mancini-Filho, Jorge E-mail: jmancini@usp.br; Delincee, Henry E-mail: henry.delincee@bfe.uni-karlsruhe.de; Villavicencio, A.L.C.H. E-mail: villavic@net.ipen.br

    2004-10-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a {sup 60}Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0 kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  9. Identification of gamma-irradiated papaya, melon and watermelon

    Science.gov (United States)

    Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

    2004-09-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  10. Sensitivity of rice varieties to gamma irradiation

    Directory of Open Access Journals (Sweden)

    R.Sasikala and R.Kalaiyarasi

    2010-07-01

    Full Text Available Six promising rice varieties viz., CO 43, CO 47, CO 48, CO 49, ADT 43 and Improved White Ponni were treated withgamma irradiation with doses of 100Gy, 200Gy, 250Gy, 300Gy and 350Gy of gamma rays in order to study effect of gammairradiation in seed germination of rice varieties and study the root and shoot length variation. Treated seeds were sownseparately in germination paper and nursery with the two replications. The germination percentage was decreased aftergamma irradiation. But the decrease was neither proportional to the increase in dosage nor definite pattern was found in allthe six rice varieties. At the dose of 350Gy all the six varieties exhibited the low germination percentage especially in thevariety ADT 43 is 33%. The gamma ray dose of 300Gy was causing 42-51% seedling height reductions in CO 43, CO 47,CO 48, CO 49 and ADT43. The seedling height was decreased in decreasing manner with the increase of irradiation dose inthe varieties such as CO 47 and improved white ponni. The root development in seedlings was inhibited higher in the dose of300Gy in all the six varieties. At higher dose of 350Gy root length is very much affected in the varieties viz., CO 43 with76% reduction and 70% reduction in improved white ponni. Plant height and seed fertility percentage were decreased withincrease of gamma radiation dose in linear fashion. Seed fertility decreased with increase of radiation dose was observed inCO 47, ADT 43 and improved white ponni. In ADT 43 seed fertility was reduced approximately 69% at gamma ray dose of350Gy.

  11. Effect of gamma irradiation on Korean traditional multicolored paintwork

    International Nuclear Information System (INIS)

    Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe2O3), Jangdan (Minium; Pb3O4), Whangyun (Crocoite; PbCrO4), and Jidang (Rutile; TiO2), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d’Eclairage (CIE) color values (L*, a*, b*) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE* unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong. - Highlights: • Effects of gamma irradiation on the Dancheong were evaluated. • We confirmed that optical and structural properties of Dancheong were maintained. • Irradiation can contribute the decontamination for

  12. The influence of {gamma}-irradiation on electrophysical properties of spinel-based oxide ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Kovalskiy, A.P.; Shpotyuk, O.I. E-mail: karat@ipm.lviv.ua; Hadzaman, I.V.; Mrooz, O.Ya.; Vakiv, M.M

    2000-05-02

    The influence of {sup 60}Co {gamma}-irradiation with 1.25 MeV average energy and 1 MGy absorbed dose on electrophysical properties of Cu-, Ni-, Co- and Mn-based spinel ceramic materials in the Cu{sub x}Ni{sub 1-x-y}Co{sub 2y}Mn{sub 2-y}O{sub 4} (0,1{<=}x{<=}0,8;0,1{<=}y{<=}0,9-x) system is investigated. The {gamma}-induced increasing of the electrical resistance is observed for the investigated samples of various compositions. It is supposed that these changes are explained by cationic redistribution in the spinel sublattices of the ceramics.

  13. Characterization of PE-g-HEMA films prepared by gamma irradiation through nuclear microprobe techniques

    Science.gov (United States)

    Ferreira, L. M.; Leal, J. P.; Rodrigues, P. A.; Alves, L. C.; Falcão, A. N.; Gil, M. H.

    2012-09-01

    PE-g-HEMA films with different grafting yields prepared by mutual gamma irradiation method at a 60Co source were characterized with ion beam analytical techniques using a nuclear microprobe. Qualitative analysis showed a random and heterogeneous distribution of contaminant elements, independent of the grafting degree, suggesting the existence of several sources of contamination at different stages of their preparation. Results also suggest that this "phased" contamination occurs simultaneously with mechanisms of agglomeration/entrapment of impurities during the gamma induced copolymerization reaction. Moreover, quantitative data showed that all contaminants found in the copolymeric films are natural contaminants of their reagents of preparation, although at concentrations without toxicological hazard, which points to a low cytotoxic potential.

  14. Application of gamma irradiation for incorporation of rubber powder in the formulations

    International Nuclear Information System (INIS)

    The aim of this paper was to study the behavior of rubber recycle, in powder form of rubber industry. It was used EPDM rubber powder. The rubber powder was irradiated and used directly in classical formulations of rubber vulcanizate. The master-batch processed material was irradiated at doses of 50, 100 and 150kGy in 60Co source at 5kGy s-1 rate, at room temperature. Gamma radiation created active sites devulcanization for further integration of the material (rubber powder) with facilities in formulations of commercial use. The processes were compared and their products were characterized by analytical methods of the physical properties such as tensile strength, elongation, hardness, rheology and abrasion tests. (author)

  15. Application of gamma irradiation for incorporation of rubber powder in the formulations

    Energy Technology Data Exchange (ETDEWEB)

    Kiyan, Ludmila Y.P.; Lugao, Ademar B.; Parra, Duclerc F., E-mail: ludmilapozzo@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Zaharescu, Traian [R and D Institute for Eiectrieal Engineering (ICEP), Bucharest, (Romania)

    2013-07-01

    The aim of this paper was to study the behavior of rubber recycle, in powder form of rubber industry. It was used EPDM rubber powder. The rubber powder was irradiated and used directly in classical formulations of rubber vulcanizate. The master-batch processed material was irradiated at doses of 50, 100 and 150kGy in {sup 60}Co source at 5kGy s{sup -1} rate, at room temperature. Gamma radiation created active sites devulcanization for further integration of the material (rubber powder) with facilities in formulations of commercial use. The processes were compared and their products were characterized by analytical methods of the physical properties such as tensile strength, elongation, hardness, rheology and abrasion tests. (author)

  16. Effectiveness of DMSO and cystein survival time and testes weight on white rats by gamma irradiation

    International Nuclear Information System (INIS)

    An investigation on the effectiveness of two radioprotectors (DMSO and cystein) separately and in combination to suppress radiation effect (survival time and testes weight) has been carries out. One hundred and forty four male rats 2 mounths 21 days old and of 142.549+/-3.588 grams body weight were divided into four groups and each group was injected intramusculary with 1.4 ml aquabides 0.4 ml DMSO, 120 mg cystein and DMSO+cystein (0.4+120 mg). Each group was divided into six subgroups and irradiated with gamma rays from a 60 Co gamma cell-220 machine with doses of 0.0; 0.5; 1.0; 2.0; 4.0; and 6.0 Gy, respectively. On days 1, 7, 14, 21, and 30 post irradiation, the rats were killed for observations of the testes weight and the survival time. The results showed that with increasing dose of irradiation, testes weight decreased, and 6 Gy caused a descrease up to 40% on day 30 post irradiation. The administration of radioprotectors could lessen the decrease of testes weight in which combined radioprotectors was most effective. Also, combines radioprotectors were most effective in prolonging the survival time of rats irradiated with dose up to 6 Gy. (authors), 6 refs.; 2 tabs.; 1 fig

  17. Modification of the microstructure of the films formed by gamma irradiated starch examined by SEM

    Science.gov (United States)

    Cieśla, K.; Sartowska, B.

    2016-01-01

    The paper concerns the effect of gamma irradiation carried out for starch on the microstructure of the films prepared using the starch and its composition with sodium laurate (NaLau) and cetyltrimethylammonium bromide (CTAB) studied by scanning electron microscopy (SEM). Potato starch was irradiated with 60Co gamma rays applying a dose of 30 kGy. Films were prepared by the solution casting method with the addition of 30 wt% glycerol as a plasticizer. Films containing NaLau and CTAB were prepared after performing the procedure, leading to starch-surfactant complexes. Mechanical tests and wetting angle measurements were performed for the films. SEM observations were carried out for the surfaces, fractures and/or sections of the films subjected to chemical fixation and for the dried films. The films obtained using irradiated starch are characterized by a smoother and more homogeneous structure as compared to those based on the non-irradiated starch. Besides, a number of small precipitates were observed on the films surfaces after drying and the number of those precipitates seemed to be higher after irradiation. The results can be related to differences in the microstructure of gels formed on the intermediate step of the films preparation and to the presence of two phases in the system and might serve for explanation of the radiation induced improvement of the hydrophilic/hydrophobic properties, a modification of the mechanical properties of the films, as well as for the changes of those properties resulting after storage.

  18. Human fibroblasts (KMST-6/RAS line) transformed with 60Co gamma-rays and c-Ha-ras oncogene constitutively produce a large amount of human granulocyte-colony stimulating factor (G-CSF)

    International Nuclear Information System (INIS)

    Human fibroblasts (KMST-6/RAS) transformed with 60Co gamma-rays and the Ha-ras oncogene formed tumors in nude mice. These mice showed splenomegaly and an increase in granulocytes in the peripheral blood. There was a direct correlation between tumor size and spleen size. Histologically, prominent proliferation of granulocytes was observed in the enlarged spleen. These findings indicated that KMST-6/RAS cells might have been producing granulocyte colony-stimulating factor (G-CSF) in the nude mice. In fact, in vitro studies demonstrated that the cells produced G-CSF in the culture medium and that production of G-CSF was greater during the logarithmic growth than during the stationary phase. Nearly equal amounts of G-CSF were produced by cells grown in serum-free or 10% serum-supplemented medium. Neither expression of the ras oncogene nor the tumorigenicity of cells correlated with the production of G-CSF. G-CSF production in KMST-6/RAS cells was significantly stimulated by butyrate, but not by dexamethasone or 5-azacytidine. (author)

  19. Identification of gamma ray irradiated wheat by electron spin resonance, DNA comet assay and germination test

    International Nuclear Information System (INIS)

    In several countries, there has been an increase in the use of radiation for food processing thus improving the quality and sanitary conditions, inhibiting pathogenic microorganisms, delaying the natural aging process and so extending product lifetime. The need to develop analytical methods to detect these irradiated products is also increasing. The goal of this research was to identify wheat irradiated using three different techniques: Electron spin resonance, DNA comet assay and germination test, for comparison. Wheat variety IAC 289 and husked wheat variety IAC 355 was from Instituto Agronomico de Campinas. Grains were irradiated with a gamma 60Co source (Gammacell 220 GC) in the Centro de Energia Nuclear na Agricultura and in the Instituto de Pesquisas Energeticas e Nucleares. Dose rate used were 1.6 kGy/h and 5.8 kGy/h. Applied doses were 0.0 kGy ; 0.10 kGy ; 0.25 kGy ; 0.50 kGy ; 0.75 kGy ; 1.0 kGy and 2.0 kGy. After irradiation, grains were analyzed over a 6 month period. It is possible to use E8R to identify irradiated husked wheat until 3 weeks after the date of irradiation. Comet assay was a qualitative test that we used to identify irradiated wheat at least 6 months after storage. The germination test make possible the identification and the better criteria was the shoot length. (author)

  20. Effect of gamma irradiation on shelf life extension, total counts of microbials and biochemical sensory change on luncheon meat

    International Nuclear Information System (INIS)

    To investigate the effect of gamma irradiation and sodium nitrate on storability and marketability of luncheon, packed luncheon was exposed to several treatments; gamma irradiation at doses 0, 1, 2, 3 and 4 KGy using a 60 CO package irradiator, mixed with sodium nitrite (NaNO2) 60 mg/Kg meat, with no irradiation and a combined treatment of both NaNO2 treatment and irradiated with a dose of 2 KGy only. Half of the irradiated and unirradiated samples were stored in refrigeration (1-4 centigrade), to study storability and the second half were stored at room temperature (18-20 centigrade) to study marketability of luncheon. During storage period the population of microorganisms, biochemical changes and sensory properties were evaluated every two weeks for the refrigerated samples and weekly for the unrefrigerated samples. The results indicated that gamma irradiation and sodium nitrite reduced the counts of microorganisms and increased the shelf-life of luncheon. Both treatments (irradiation, sodium nitrite) increased total acidity, lipid oxidation, and the volatile basic nitrogen (VBN) immediately after processing and reduced all of them through out storage. Sensory evaluation (firmness, color, taste, and flavor) indicated no significant differences (P>0.05) between treated and untreated samples. (author)

  1. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS

    Energy Technology Data Exchange (ETDEWEB)

    Clark, E.

    2011-09-22

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer

  2. Effect of gamma irradiation on Korean traditional multicolored paintwork

    Science.gov (United States)

    Yoon, Minchul; Kim, Dae-Woon; Choi, Jong-il; Chung, Yong-Jae; Kang, Dai-Ill; Hoon Kim, Gwang; Son, Kwang-Tae; Park, Hae-Jun; Lee, Ju-Woon

    2015-10-01

    Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe2O3), Jangdan (Minium; Pb3O4), Whangyun (Crocoite; PbCrO4), and Jidang (Rutile; TiO2), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d'Eclairage (CIE) color values (L*, a*, b*) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE* unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong.

  3. EPR investigation of some gamma-irradiated excipients

    Science.gov (United States)

    Aleksieva, Katerina; Yordanov, Nicola D.

    2012-09-01

    The results of electron paramagnetic resonance (EPR) studies on some excipients: lactose, microcrystalline cellulose (avicel), starch, dioxosilane (aerosil), talc and magnesium stearate before and after gamma-irradiation are reported. Before irradiation, all samples are EPR silent except talc. After gamma-irradiation, they show complex spectra except magnesium stearate, which is EPR silent. Studies show the influence of gamma-irradiation on EPR spectra and stability of gamma-induced radicals. Analysis of the EPR spectrum of gamma-irradiated talc shows that this material is radiation insensitive. Only lactose forms stable-free radicals upon gamma sterilization and can be used for identification of radiation processing for a long time period thereafter.

  4. Gamma irradiation effects on human growth hormone producing pituitary adenoma tissue

    International Nuclear Information System (INIS)

    Irradiation-induced effects on pituitary cell morphology and secretion of growth hormone (GH) and prolactin (PRL) have been analysed using an in vitro system. Specimens for organ culture were were obtained from three patients with pituitary tumours causing acromegaly but with different clinical activity of disease. Specimens were followed in vitro 1 h - 6 days after single-dose gamma irradiation (60Co) with 70 100 and 150 Gy, respectively. These doses are used in clinical work for the stereotactic radiosuregery of pituitary adenomas. Considerable fluctuations in hormone secretion/release occurred during the first 24h after irradiation. All three tumours showed individual differences concern ing irradiation-induced morphological damage. Only a minor variation occurred between specimens from the same tumour. An individual sensitivity to irradiation of pituitary tumours in vitro is documented. The great number of surviving pituitary tumour cells one week after irradiation-many with an intact ultrastructure and containing hormone granules-indicated an initial high degree of radioresistance. (author)

  5. Optical studies in gamma-irradiated commercial soda-lime silicate glasses

    International Nuclear Information System (INIS)

    Optical absorption measurements of gamma-irradiated (60Co) commercial soda-lime silicate (SLS) glasses were performed at room temperature (RT) to detect and characterize the induced radiation damage in these materials. Isothermal bleaching (RT-723 K) of the radiation-induced defects, followed the irradiation of samples. In glasses containing different amount of the glass-network modifiers (Na2O, K2O) and some multivalent transition metal cations (Fe2+/Fe3+, Ni2+ and/or Mn2+) three absorption bands have been distinguished in the wavelength region extending from 250 to 1800 nm. In contrast to the electron-type color centers, detected at low temperatures for X-irradiated nominally pure sodium silicates , we propose that the absorption bands found for gamma-irradiated SLS glasses are induced by some hole-type color centers related with nonbridging oxygen ions (NBO-) located in different surroundings. The radiation-induced enhancement of diffusivity of ions together with bond breaking and defect creation in the glass-network could give materials with well-defined nonlinear optical properties

  6. Detection of garlic gamma-irradiated by assay comet

    International Nuclear Information System (INIS)

    The garlic samples were irradiated in a facility with 60Co sources, at absorbed dose values of 0-0,15 kGy. The detection method utilized for the identification of the irradiated garlic was biological comet assay. The samples were classified post-irradiation several times. The irradiated samples showed high strand breaks of DNA exhibiting comets of several forms, while the not irradiated and lower dose samples showed a behavior like round shape and light comets. Significant differences were found for higher absorbed dose values at 0.06 kGy, this absorbed dose value is corresponding with the applied dose value at this food in order to avoid the germination. (author)

  7. Detection of garlic gamma-irradiated by assay comet

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Alvarez, Damaris L.; Miranda, Enrique F. Prieto; Carro, Sandra; Iglesias Enrique, Isora; Matos, Wilberto [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), Ciudad de La Habana (Cuba)], e-mail: damaris@ceaden.edu.cu

    2009-07-01

    The garlic samples were irradiated in a facility with {sup 60}Co sources, at absorbed dose values of 0-0,15 kGy. The detection method utilized for the identification of the irradiated garlic was biological comet assay. The samples were classified post-irradiation several times. The irradiated samples showed high strand breaks of DNA exhibiting comets of several forms, while the not irradiated and lower dose samples showed a behavior like round shape and light comets. Significant differences were found for higher absorbed dose values at 0.06 kGy, this absorbed dose value is corresponding with the applied dose value at this food in order to avoid the germination. (author)

  8. The effect of gamma irradiation on injectable human amnion collagen

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.C.; Harrell, R.; Davis, R.H.; Dresden, M.H.; Spira, M. (Institute of Occupational Medicine, Beijing (China))

    1989-08-01

    The effect of gamma irradiation on the physicochemical properties of injectable human amnion collagen was investigated. Pepsin-extracted human amnion collagen was purified, reconstituted, and irradiated with varying doses of gamma irradiation (0.25 Mrads to 2.5 Mrads). Gamma irradiation had a significant impact on the physical characteristics of the collagen. The neutral solubility of collagen in PBS at 45{degrees}C was decreased from 100% for the nonirradiated control sample to 16% for the 2.5 Mrads irradiated sample. SDS polyacrylamide gel electrophoresis also demonstrated the dose-dependent effect of gamma irradiation on collagen cross-links. Electron microscopic observation revealed that even at low irradiation dose (0.25 Mrads), collagen fibril diameter increased. The average diameter was 50 nm for nonirradiated control fibrils, while 4.4% of the irradiated collagen fibrils had a diameter greater than 100 nm. Irradiated collagen showed little evidence of damage. Well-preserved cross-striations were found in collagen fibrils at all doses of irradiation. Native amnion collagen irradiated with gamma rays demonstrated a slight increase in resistance to collagenase degradation compared with nonirradiated native collagen samples. Increased resistance to collagenase did not correlate with increasing irradiation dose. After 30 min of incubation at 37{degrees}C, both irradiated and nonirradiated collagen was completely digested by collagenase. However, gamma-irradiated collagen did become more sensitive to hydrolysis by trypsin. The higher the irradiation doses used, the greater sensitivity to trypsin was observed. At 0.25 Mrads irradiation only a slight increase was found. No marked differences in amino acid composition were noted among the high dose irradiated, low dose irradiated and control amnion collagen.

  9. Description of morphologic characters in avocado trees (Persea americana. Mill) var. Hass, submitted to gamma radiation of {sup 60} Co; Descripcion de caracteres morfologicos en arboles de aguacate (Persea americana. Mill) var. Hass, sometidos a radiacion gama de {sup 60} Co

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval R, L

    2004-07-01

    It was carried out the characterization of 77 trees of avocado ''Hass'' subjected to gamma radiation of Co{sup 60}, in doses of 0, 5, 10,15, 20 and 25 Gy based on previous studies of radiosensitivity with ends of improvement located in the experimental center ''La Labor'' belonging to the foundation Salvador Sanchez Colin. CICTAMEX. S C. in Temascaltepec, Mexico. It was carried out the morphological characterization of this variety according to the nomenclature settled down by the International Office of Genetic Resources (IBPGRI), registering 27 variables for the description of the tree, 33 for description of the fruit and 14 for the characterization of the seed. Regarding the architectural characterization 10 variables were evaluated. Using gamma radiation of Co{sup 60} in the doses of 15 and 20 Gy it was detected a reduction of 22% in the portage of the tree, likewise had reduction the diameter of the trunk and of the foliage. It was found that the reduction in the behavior of the tree induces to a bigger variation of the form of the same one, in the distribution of the branches in the form of the fruit and in the form of the seed you Also detects a remarkable increment in the productivity of some hoist irradiated regarding the architecture of the tree one observes that the angle of inclination of the branches increase when being increased the radiation dose and that the longitude of the annual section of growth decreased significantly in the doses of 20 and 25 Gy. One observes a significant Increment in the I number of buds prolepticos in those hoist irradiated in the I finish mbdulo of rhythmic growth. Io that indicates a change substantial in the I inhabit of growth With the purpose of determining if the changes in morphology and architecture of the tree corresponded with the modification at level meristematico, they were carried out observations to the court microscope of having knitted apical vegetative meristematico

  10. Degradation of corn starch under the influence of gamma irradiation

    International Nuclear Information System (INIS)

    Irradiation of corn (maize) starch with different doses of gamma irradiation ranging from 1 x 105 rad to 1 x 106 rad resulted in the increase of starch acidity and reducing power. Molecular degradation was observed as a result of marked decrease in starch viscosity and intinsic viscosity as well as swelling capacity. The gelatinization time and temperature of the irradiated starch became shorter than in the control sample. Internal changes in the irradiated starch occured as a result of lowering the number of glucose unit per segment in the irradiated starch molecules. All changes were proportional to the doses of gamma irradiation used. (orig.)

  11. Gamma irradiation reduces the immunological toxicity of doxorubicin, anticancer drug

    Science.gov (United States)

    Kim, Jae-Hun; Sung, Nak-Yun; Raghavendran, H. Balaji; Yoon, Yohan; Song, Beom-Seok; Choi, Jong-il; Yoo, Young-Choon; Byun, Myung-Woo; Hwang, Young-Jeong; Lee, Ju-Woon

    2009-07-01

    Doxorubicin (DOX) is a widely used anticancer agent, but exhibits some immunological toxicity to patients during chemotherapy. The present study was conducted to evaluate the effect of gamma irradiation on the immunological response and the inhibition activity on in vivo tumor mass of DOX. The results showed that DOX irradiated at 10 and 20 kGy reduce the inhibition of mouse peritoneal macrophage proliferation and induce the release of cytokines (TNF-α and IL-6) when compared with non-irradiated DOX. The cytotoxicity against human breast (MCF-7), murine colon adenocarcinoma (Colon 26) and human monocytic (THP-1) tumor cell were not significantly different between non-irradiated and irradiated DOX ( Pstatistically non-significant as compared with non-irradiated DOX. In conclusion, gamma irradiation could be regarded as a potential method for reducing the immunological toxicity of DOX. Further researches is needed to reveal the formation and activity of radiolysis products by gamma irradiation.

  12. Assessment of differences between X and gamma rays in order to validate a new generation of irradiators for insect sterilization

    Energy Technology Data Exchange (ETDEWEB)

    Mastrangelo, Thiago; Walder, Julio M.M., E-mail: piaui@cena.usp.b [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil); Parker, Andrew G.; Jessup, Andrew; Orozco-Davila, Dina; Islam, Amirul; Dammalage, Thilakasiri, E-mail: A.Jessup@iaea.or [Joint FAO/IAEA-UN A-2444, Seibersdorf (Austria). Insect Pest Control Subprogramme; Pereira, Rui, E-mail: R.Cardoso-Pereira@iaea.or [Joint FAO/IAEA-UN, Vienna (Austria). Insect Pest Control Subprogramme

    2009-07-01

    Recent fears of terrorism provoked an increase in delays and denials of transboundary shipments of radioisotopes. This represents a serious constraint to sterile insect technique (SIT) programs around the world as they rely on the use of ionizing energy from radioisotopes for insect sterilization. In order to validate a novel Xray irradiator, a series of studies on Ceratitis capitata (Wiedemann) and Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) were carried out, comparing the relative biological effectiveness (RBE) between X-rays and traditional gamma radiation from {sup 60}Co. Male C. capitata pupae and pupae of both sexes of A. fraterculus, both 24 to 48 h before adult emergence, were irradiated with doses ranging from 15 to 120 Gy and 10 to 70 Gy respectively. Estimated mean doses of 91.2 Gy of X and 124.9 Gy of gamma radiation induced 99% sterility in C. capitata males. Irradiated A. fraterculus were 99% sterile at about 40-60 Gy for both radiation treatments. Standard quality control parameters were not significantly affected by the two types of radiation. There were no significant differences between X and gamma radiation regarding mating indices. The RBE did not differ significantly between the tested X and gamma radiation, and X-rays are as biologically effective for SIT purposes as gamma rays are. This work confirms the suitability of this new generation of X-ray irradiators for pest control programs in UN Member States. (author)

  13. Evaluation of the radio modifier effect of propolis on chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60-CO; Avaliacao do efeito radiomodificador da propolis em celulas de ovario de hamster chines (CHO-K1) e em celulas tumorais de prostata (PC3), irradiadas com CO-60

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Geyza Spigoti

    2011-07-01

    In the last decades, it has been given a great interest to investigations concerning natural, effective, nontoxic compounds with radioprotective potential together with the increasing utilization of different types of ionizing radiation for various applications. Among them propolis, a resinous compound produced by honeybees (Apis mellifera), has been considered quite promising, since it presents several advantageous biological characteristics, i. e., anti-inflammatory, antimicrobial, anticarcinogenic, antioxidant and also free radical scavenging action. The purpose of the present study was to evaluate the effect of Brazilian propolis, collected in the State of Rio Grande do Sul, on Chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with {sup 60}Co {gamma} radiation. For this purpose, three interlinked parameters were analyzed: micronucleus induction, cell viability and clonogenic death. The choice of these parameters was justified by their biological significance, in addition to the fact that they are readily observable and measurable in irradiated cells. The cytogenetic data obtained showed a radioprotective effect of propolis (5-100 {mu}g/ml) in the induction of DNA damage for both cell lines, irradiated with doses of 1 - 4 Gy. The cytotoxicity assay, however, showed a prominent antiproliferative effect of propolis (50 - 400{mu}/ml) in PC3 cells irradiated with 5 G{gamma}. The survival curves obtained were adequately fitted by a linear-quadratic model, where the {alpha} coefficient was higher in CHO-K1 cells. Concerning the clonogenic capacity, PC3 cells were more radiosensitive than CHO-K1 cells at the higher doses of the survival curve. Propolis at the concentrations of 30 - 100 {mu}g/ml, did not influence the clonogenic potential of PC3 cells, since the survival curves, associated or not with propolis, were found similar, although the combined treatment in CHO-K1 cells exhibited a stimulating proliferative effect. The data

  14. Caffeine degradation in water by gamma irradiation, ozonation and ozonation/gamma irradiation

    Directory of Open Access Journals (Sweden)

    Torun Murat

    2014-03-01

    Full Text Available Aqueous solutions of caffeine were treated with ozone and gamma irradiation. The amounts of remaining caffeine were determined after solid phase extraction as a function of absorbed dose and ozonation time. In addition to this, some important parameters such as inorganic ions, chemical oxygen demand (COD dissolved oxygen and total acidity changes were followed. Caffeine (50 ppm is found to be completely decomposed at 3.0 kGy and 1.2 kGy doses in the absence of H2O2 and in 1.20 mM H2O2 solutions, respectively. In the case of gamma irradiation after ozonation, 50 ppm caffeine was removed at 0.2 kGy when the solution was ozonized for 100 s at a rate of 10 g O3 h-1 in 400 mL 50 ppm paracetamol solution.

  15. Evaluation of immunity and protection induced in experimental models by soluble extract of Toxoplasma gondii tachyzoites irradiated by {sup 60}Co; Avaliacao da imunidade e protecao induzida em modelos experimentais por extrato soluvel de taquizoitos de Toxoplasma gondii irradiado por {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Andrea da

    2013-07-01

    Toxoplasmosis affects 1/3 of the human population and only a vaccine for veterinary use. Gamma radiation alters the proteins making them more immunogenic by oxidation and better antigen presentation in the absence of adjuvants. Radiate soluble extract of RH strain tachyzoites of T. gondii (AgTg), and evaluate its use as a vaccine in BALB/c. Doses below 500Gy not affected and destroyed 2000Gy doses above extract, whereas animals immunized with irradiated extract at 1000, 1500 and 2000Gy had more of specific IgG avidity , compared to native AgTg (p<0,05) . AgTg 1500GY the immunized animals had increased proliferation of splenocytes, phenotyped as CD3+CD4+, CD3+CD8+ and B-lymphocytes immunized animals compared to the native AgTg . Animals immunized by AgTg 1500GY after challenge with strain ME- 49 cystogenic showed lower number of brain cysts and greater survival after challenge with virulent RH. Ionizing radiation in extracts of T. gondii increases the immune response and immune memory in the absence of adjuvants. (author)

  16. Effect of gamma irradiation on toxicity and immunogenicity of Androctonus australis hector venom

    Energy Technology Data Exchange (ETDEWEB)

    Abib, L. [Univ. des Sciences et de la Technologie, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Houari Boumedienne, Bab Ezzouar (Algeria); Laraba-Djebari, F. [Univ. des Sciences et de la Technologie, Lab. de Biologie Cellulaire et Moleculaire, Faculte des Sciences Biologiques, Houari Boumedienne, Bab Ezzouar, Alger (Algeria); Institut Pasteur d' Algerie, Lab. de Recherche et de Developpement sur les Venins, Alger (Algeria); E-mail: flaraba@ibnsina.ands.dz

    2003-12-01

    An investigation was made of the radiosensitivity of the toxic and immunological properties of Androctonus australis hector venom. This venom was irradiated with two doses of gamma rays (1 and 2 kGy) from a {sup 60}Co source. The results showed that venom toxicity was abolished for the two radiation doses (1 and 2 kGy) with, respectively, 10 and 25 times its initial LD50 value. However, irradiated venoms were immunogenic, and the antibodies elicited by them were able to recognize the native venom by enzyme-linked immunosorbent assay. Antisera raised against these toxoids (1 and 2 kGy) had a higher neutralizing capacity and immunoreactivity against all components of native venom than did the antiserum produced against the native venom. The antiserum of rabbits immunized with 2-kGy-irradiated venom was more efficient than 1-kGy-irradiated toxoid antiserum. Indeed, in vivo protection assays showed that the mice immunized with 2-kGy-irradiated venom resisted lethal doses (i.p.) of A. australis hector venom. (author)

  17. Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Andre Moreira; Alves, Glaucie J.; Aires, Raquel da Silva; Turibio, Thompson O.; Thomazi, Gabriela O. Coelho; Spencer, Patrick J.; Nascimento, Nanci do, E-mail: andrerocha@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nascimento-Rocha, Josefa M.; Magalhaes Filho, Asterio Souza, E-mail: 0304@prof.itpacporto.com.br [Instituto Tocantinense Presidente Antonio Carlos Porto (ITPAC), Porto Nacional, TO (Brazil)

    2015-07-01

    Snake venoms are complex mixtures of proteins and peptides with a wide spectrum of physiological targets such as the blood coagulation and cardiovascular systems and the motor end plate among others. Acute renal failure is a common complication in accidents with the South American rattlesnake. The toxin involved in this pathology is the crotoxin, a major component of the venom in terms of concentration and toxicity. Snake venoms, when irradiated with {sup 60}Co gamma rays present a significant decrease in toxicity while the immunogenic properties of its components are preserved. The use of irradiated venom is an attractive alternative for antisera production since it might reduce the appearance of renal lesions improving the welfare and lifespan of those animals employed on antivenom production. At the present work, we have compared the effects of native and irradiated crotoxin on the mice renal function. Tubular lesions were observed in all the samples from the animal group injected with native crotoxin. Animals injected with the irradiated toxin presented alteration only after 30 minutes and 1 hour after injection. These data suggest that the onset of the renal lesions is delayed and that the severity of the lesions might be lower when using irradiated crotoxin. (author)

  18. Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

    International Nuclear Information System (INIS)

    Snake venoms are complex mixtures of proteins and peptides with a wide spectrum of physiological targets such as the blood coagulation and cardiovascular systems and the motor end plate among others. Acute renal failure is a common complication in accidents with the South American rattlesnake. The toxin involved in this pathology is the crotoxin, a major component of the venom in terms of concentration and toxicity. Snake venoms, when irradiated with 60Co gamma rays present a significant decrease in toxicity while the immunogenic properties of its components are preserved. The use of irradiated venom is an attractive alternative for antisera production since it might reduce the appearance of renal lesions improving the welfare and lifespan of those animals employed on antivenom production. At the present work, we have compared the effects of native and irradiated crotoxin on the mice renal function. Tubular lesions were observed in all the samples from the animal group injected with native crotoxin. Animals injected with the irradiated toxin presented alteration only after 30 minutes and 1 hour after injection. These data suggest that the onset of the renal lesions is delayed and that the severity of the lesions might be lower when using irradiated crotoxin. (author)

  19. Studies of agregates produced during venom irradiation of Crotalus durissus terrificus with gamma ray

    International Nuclear Information System (INIS)

    Literature data show that 2.0 kGy dose of gamma radiation, generated by 60 Co source, reduces the toxic activity of Crotalus durissus terrificus venon, without altering its immunogenic capacity. When crotoxin, main toxin from crotalic venom, was irradiated with the same dose, toxicity was laos reduced and the immunogenicity was maintained. This fact was attributed to aggregates(compounds with high molecular weight generated during irradiation), that showed no toxicity but were able to induce the antibodies formation against native venom. Crotalus durissus terrificus venom was irradied with 2.0, 3.0, 5.0 and 10.0 kGy doses and submitted to molecular exclusion chromatography, in order to find an efficient dose that produces large amounts of non toxic but still immunogeneic aggregates. After being isolated, the products of irradiation were evaluated for the amount produced, molecular ateration, and toxic and immunogenic activities. The results from different doses irradiated venom were compared with native one, and 2.0 kGg dose was confirmed to be most efficient in the association of toxicity attenuation with maintenance of immunogenicity of the crotalic venom, while other doses, in spite of being efficient in the toxicity attenuation, they were not able to keep the immunogenicity property. So, the dose of 2.0 kGy could be used to immunize animals in order to improve anticrotalic sera production. (author). 14 refs., 6 figs., 4 tabs

  20. Effect of gamma irradiation on seed germination, growth and biochemical parameters of Flacourtia Montana Graham

    International Nuclear Information System (INIS)

    Flacourtia montana an endemic species of Western Ghat which is well known for its ethno-medicinal value was chosen for the study. Matured seeds collected from Beithangady region of Dakshina Kannada district were irradiated with different doses (0, 25, 50, 100, 150, 200, 250, 300 Gy) of gamma radiation using 60Co gamma source at Board of Radiation and Isotope Technology (BRIT). Effect of gamma radiation on growth and biochemical constituents were compared with that of control plants. An increase in germination percentage, speed and vigour index was observed at lower dosages, and the dose of 100 Gy was found to be more effective out of the selected doses as far as growth is concerned. Doses of 25 and 100 Gy showed 95 and 100% germination respectively but the germination was reduced at higher dosages. Total chlorophyll content at 10 Gy was found to be 19.56 mg/gfw while in control was 14 mg/gfw. Phenolic content was higher at 50 Gy and proline content at 150 Gy. Slight increase in carbohydrate content was observed in irradiated samples. Hence, lower doses of radiation treatment may be recommended to increase growth and phenolic content of plant F.montana. (author)

  1. The Research on Effect of 60CoγIrradiation on Radiolysis Behavior of BOPA/CPP Packaging Materials by GC/MS%气相色谱质谱联用法分析60Coγ对包装材料双向拉伸尼龙/流延聚丙烯(BOPA/CPP)的辐解行为的影响

    Institute of Scientific and Technical Information of China (English)

    王宽强; 贺承启; 张勋龙; 彭秧

    2015-01-01

    This article researched radiolysis Behavior of 60 Coγirradiated BOPA/CPP Packaging Material by GC/MS. In full scan mode,all the 60 compounds were determined by spectrum,the mainly new radiolysis products were benzene,1,3 bis (1,1-dimethylethyl)and 2,5-Cyclohexadiene1,4-dione;At the same time,the contents of benzene,1,3,bis(1,1-di⁃methylethyl);Phenol,2,4-bis(1,1-dimethylethyl);2,5-Cyclohexadiene1,4-dione;Phenol 2,6--bis(1,1-dimethyleth⁃yl ) ,2,6-bis(1,1-dimethylethyl);Bis(cis-13-docosenamido)methane had obvious changes ,but the other radiolysis products had few changes at different irradiation intensities.%利用气相色谱质谱联用法研究了,受不同强度60Coγ辐照的包装材料BOPA/CPP的辐解行为;经过谱库检索,共检出60多种辐解产物,其中新检出主要的辐解产物有1,3-二叔丁基苯、2,6-二叔丁基苯醌;在不同的辐照强度下,1,3-二叔丁基苯,2,4二叔丁基苯酚,2,6二叔丁基对苯醌,4-乙基,2,6-二叔丁基苯酚,顺芥酸酰胺等物质发生了较明显的变化,其余辐解物没有发生太大的变化。

  2. Optical and electron beam studies of gamma-irradiated AlGaN/GaN high-electron-mobility transistors

    Science.gov (United States)

    Yadav, Anupama; Glasscock, Cameron; Flitsiyan, Elena; Chernyak, Leonid; Lubomirsky, Igor; Khodorov, Sergey; Salzman, Joseph; Meyler, Boris; Coppola, Carlo; Guay, Sebestian; Boivin, Jasques

    2016-03-01

    The impact of 60Co gamma-irradiation on n-channel AlGaN/GaN high-electron-mobility transistors was studied by means of temperature-dependent electron beam-induced current (EBIC) and cathodoluminescence (CL) techniques. For the doses up to ∼250 Gy, an enhancement of minority carrier transport was observed as evident from the EBIC measurements. This enhancement is associated with internal electron irradiation induced by the primary gamma photons. For the doses above ∼250 Gy, deterioration in minority carrier transport was explained by carrier scattering on radiation-induced defects. It is shown that calculated activation energy from the EBIC and CL measurements follows exactly the same trend, which implies that the same underlying phenomenon is responsible for observed findings.

  3. Sesamol attenuates cytogenetic damages in bone marrow cells of whole body gamma irradiated mice

    International Nuclear Information System (INIS)

    Whole body radiation exposure cause damages to all vital organs and bone marrow is the most sensitive. Pre-treatment with antioxidant as single prophylactic dose is expected to lower induction of damages in bone marrow. In the present study we have focused on sesamol, a dietary antioxidant mediated radioprotection in bone marrow cells of gamma irradiated mice and compared with melatonin. Male C57BL/6 mice were intraperitoneally administered with sesamol (10 and 20 mg/kg body) and after 30 minutes exposed to whole body gamma radiation using 60Co Teletherapy unit. Mice were injected with 0.2 ml of a metaphase arresting agent (0.05% colchicine) intra-peritoneally 3 hours prior to sacrifice (24 hrs. post-irradiation). Bone marrow cells were flushed out from femurs of each animal and processed for chromosomal aberration assay. Another set of experiment without colchicine injection was performed to access the DNA damage in bone marrow using alkaline comet assay. At least 100 metaphases per animal were scored under light microscope to record various aberrations and total chromosomal aberrations (TCA) was calculated. Similar measurements were performed with melatonin for comparing the efficacy of sesamol. Gamma irradiation has increased the chromatid type aberrations (break formation, fragment) and chromosomal type aberrations (ring formation, acentric) in bone marrow cells. The results have shown significant (p< 0.001) increase in TCA of irradiated mice than control. While pre-treatment of sesamol and melatonin 10 mg/kg significantly (p<0.05) reduced the TCA. The extend of protection has increased at 20 mg/kg significantly (p<0.001) as evident from the reduced TCA compared to irradiated group. Interestingly, sesamol and melatonin have shown similar extent of reduction of TCA. Thus sesamol has demonstrated strong ability to protect bone marrow at low dosage. These investigations on sesamol mediated protection in bone marrow are likely to benefit development of

  4. Gamma-irradiation stability of saturated and unsaturated aliphatic polyanhydrides--ricinoleic acid based polymers.

    Science.gov (United States)

    Teomim, D; Mäder, K; Bentolila, A; Magora, A; Domb, A J

    2001-01-01

    The effect of terminal sterilization by gamma-irradiation on several ricinoleic acid based polyanhydrides was investigated. The following polymers were used: poly(ricinoleic acid maleate) [P(RAM)], poly(ricinoleic acid succinate) [P(RAS)], poly(hydroxy stearic acid succinate) [P(HSAS)], poly(hydroxy stearic acid maleate) [P(HSAM)], and their copolymers with sebacic acid. The polymers were irradiated with an absorbed dose of 2.5 or 10 Mrad by means of a 60Co source under dry ice or at room temperature. No differences were found between samples irradiated under dry ice and at room temperature. Polymers prepared from monomers containing maleate residues, which contain double bonds adjusted to the anhydride linkage along the polymer chain, decreased in molecular weight, became insoluble, and showed fast hydrolytic degradation. For example, p(RAM), p(HSAM), and their copolymers with sebacic acid decreased in Mw from about 10,000 to about 2000, and from about 30,000 to about 5000, respectively, while polymers based on RAS and HSAS remained stable. This phenomenon was explained by an anhydride interchange-self-depolymerization process of the unsaturated anhydride bonds induced by gamma-irradiation. This explanation was supported by the depolymerization of another class of polymers having an anhydride bond between two double bonds, fumaric acid anhydride polymers. The anhydride bond that lies between two double bonds was found to be more sensitive to gamma-irradiation. This anhydride bond may be cleaved to form two radicals that further react with aliphatic anhydride bonds along the polymer chain to form inter- and/or intracyclization products. PMID:11710004

  5. Selection of male-sterile and dwarfism genetically modified zoysia japonica through gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Tae Woong; Song, In Ja; Kang, Hong Gyu; Jeong, Ok Cheol; Sun, Hyeon Jin; Ko, Suk Min; Lim, Pyung Ok; Song, Pill Soon; Song, Sung Jun; Lee, Hyo Yeon [Jeju National University, Jeju (Korea, Republic of)

    2010-09-15

    The aim of this study is selection of the male-sterile plant for inhibiting transgene flow through gamma-irradiation ({sup 60}Co) at the pollination and fertilization cycle of herbicide-tolerant genetically modified (GM) zoysiagrass (Zoysia japonica Steud.). High frequencies of plant mutations were obtained about 18% from M{sub 1} generation at the doses (10 to 50 Gy). We also found that some M{sub 1} plants showed male-sterile plants using de-husked seeds and comparison of stainable pollen using KI-I{sub 2} solution. Besides the effects of irradiation on pollination and fertilization cycle, various other mutation like dwarf, cold tolerance, increasing grains and mass were observed. Four of dwarfism plants were selected through comparison of morphological characteristic between control and mutants during 4 years. These results demonstrated that the gamma-irradiation on pollination and fertilization cycle is very effective to induce the various mutations, and the male-sterile mutants are useful for controlling transgene flow and developing of high quality turfgasses.

  6. Selection of male-sterile and dwarfism genetically modified zoysia japonica through gamma irradiation

    International Nuclear Information System (INIS)

    The aim of this study is selection of the male-sterile plant for inhibiting transgene flow through gamma-irradiation (60Co) at the pollination and fertilization cycle of herbicide-tolerant genetically modified (GM) zoysiagrass (Zoysia japonica Steud.). High frequencies of plant mutations were obtained about 18% from M1 generation at the doses (10 to 50 Gy). We also found that some M1 plants showed male-sterile plants using de-husked seeds and comparison of stainable pollen using KI-I2 solution. Besides the effects of irradiation on pollination and fertilization cycle, various other mutation like dwarf, cold tolerance, increasing grains and mass were observed. Four of dwarfism plants were selected through comparison of morphological characteristic between control and mutants during 4 years. These results demonstrated that the gamma-irradiation on pollination and fertilization cycle is very effective to induce the various mutations, and the male-sterile mutants are useful for controlling transgene flow and developing of high quality turfgasses

  7. Application of gamma irradiation for inhibition of food allergy

    Science.gov (United States)

    Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Jo, Cheorun; Kim, Hee-Yun

    2002-03-01

    This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk β-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods.

  8. Physicochemical Properties of Gamma-Irradiated Corn Starch

    International Nuclear Information System (INIS)

    Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples

  9. Gamma irradiation effects on microbial decontamination of ostrich meat

    Directory of Open Access Journals (Sweden)

    F Tabatabaei Yazdi

    2012-11-01

    Full Text Available In this work effects of gamma irradiation and storage time on microbial decontamination of fresh camel meat stored at 4˚C were evaluated. Microbial analysis indicated that irradiation had a significant effect on the reduction of microbial loads. Among the analyzed bacteria, coliforms were most sensitive to gamma radiation. Considering the sensory analyses and Total bacterial counts analyses as a whole, air-packed samples irradiated at 1.0 kGy were acceptable under refrigerated storage for 9 days, compared to 5 and 7 days for irradiated at 3.0 kGy and non irradiated air-packaged samples, respectively. 

  10. Effects of 60Co administration on early placental cells

    International Nuclear Information System (INIS)

    The effects of 60Co administration on early placental cells were studied. Placental tissue and embryo obtained by induced abortion (6 - 13 weeks gestational age) were placed in the minimal essential medium (MEM) and irradiated with various doses of 60Co. After irradiation, the villi were cultured in a CO2 incubater at 370C. Cell growth process was observed every day with the phase-contrast microscope. Between 1 and 5 days epitheloid cells were dominant, but from about 7th day on fibroblastic cells dominated the culture. In placental tissue irradiated with 100, 200, 500 rad, fibroblastic cells began to grow earlier than in non-treated. Over 3000 rad 60Co inhibited the growth of cells and a culture was impossible. For each dose, the tissue was incubated for various periods of time, exposed to tritiated thymidine for the last hour and autoradiogram was prepared by the dipping method. The labeling index of irradiated trophoblasts showed a significant decrease compared with controls. A chromosome study was made in irradiated in vitro cell lines of fetus and placenta. There was no significant difference between the two cell lines concerning the frequency of chromosome aberration, which tended to increase as the chromosome becomes longer. It is concluded that the trophoblast is highly radiosensitive and that irradiation early in pregnancy may damage DNA synthesis in the trophoblast, and induce abortion. (author)

  11. Spectral distribution of the radiochemiluminescence from gamma-irradiated humic acid

    International Nuclear Information System (INIS)

    This study was conducted to investigate radiochemiluminescence (RCL) spectra (340-650 nm), kinetics and absorption spectra of humic acids (HA) after their exposure of gamma-radiation (absorbed doses of 1-10 kGy, 60Co) in model systems. The kinetics and spectral distribution of RCL were measured using the single photon counting method (SPC) and cut-off filters. Absorption spectra (range 240-800 nm) of irradiated solutions indicated that post-radiative degradation/polymerization processes take place in the HA changing their macromolecule or properties. The intensity of the delayed RCL was nonlinearly and suggested that complex radical formation mechanisms were still involved in the post-radiative reactions. (author)

  12. Study of the Influence of Scattered Radiation at a Gamma Irradiator

    International Nuclear Information System (INIS)

    The Calibration Laboratory of IPEN offers calibration services for portable radiation monitors using a Buchler gamma irradiator with 137Cs and 60Co radioactive sources. The beam dosimetry measurements are taken periodically between the source-instrument distances of 1 m and 4 m. The ISO 4037 standard (International Organization for Standardization) states that the air kerma rate due to scattered radiation shall not exceed 5% of that due to direct radiation. To verify if the facility was in accordance to the requirements, the evaluation of the scattered radiation was performed in this work. The air kerma rates were measured on the beam axis at various distances from the source up to 5.5 m, and the radiation attenuation curve was obtained. The air kerma rates were proportional within 5% of deviation to the inverse square law from the source centre to the detector centre, as required by the ISO 4037 standard. (authors)

  13. Glycoalkaloids and phenolic compounds in gamma irradiated potatoes

    International Nuclear Information System (INIS)

    Potatoes were used to study the metabolic stress effects in irradiated vegetable products. The changes of the contents of specific target compounds (glycoalkaloids, phenolic acids and coumarins) in alcoholic extracts of gamma irradiated potatoes were studied for metabolic irradiation stress. Doses of up to 3 kGy were applied to potatoes of several varieties. (Auth.)

  14. Action of Bothrops moojeni venom and its L-amino acid oxidase fraction, treated with {sup 60}Co gamma rays, in Leishmania spp; Acao do veneno de Bothrops moojeni e sua fracao L-aminoacido oxidase, submetida ao tratamento com raios gama de {sup 60}Co, em Leishmania spp

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Andre Gustavo Tempone

    1999-07-01

    Bothrops moojeni venom showed an anti leishmania activity in vitro, as determined by a cell viability assay using the reduction of MTT. After venom purification, by chromatography techniques, the fractions with anti leishmania and L-amino acid oxidase activities, eluted in the same positions. The molecular weight of the enzyme was estimated to be 140 kDa by molecular exclusion chromatography, and 69 kDa, by SDS-PAGE, migrating as a single band, with an isoelectric point of 4.8 as determined by isoelectric focusing. The purified LAO from B. moojeni venom, 135-fold more active than crude venom, showed homo dimeric constitution, and was active against Leishmania spp from the New World, with an effective concentration against L(L). amazonensis of 1.80 {mu}g/ml (EC{sub 50}), L.(V.) panamensis (0.78 |{mu}g/ml) and L.(L.) chagasi (0.63 ({mu}g/ml). Ultrastructural studies of promastigotes affected by LAO demonstrated cell death, with edema in several organelles such as mitochondria and nuclear membrane, before cell disruption and necrosis. The action of LAO was demonstrated to be hydrogen peroxide-dependent. Studies with LLCMK-2 cells, treated with LAO, showed a toxic effect, with an EC{sub 50} of 11|{mu}g/ml. Irradiation of LAO with 6{sup 0C}o gamma rays, did not affect its whole oxidative activity, neither detoxified the enzyme. Amastigotes treated with LAO were not affected by its hydrogen peroxide, otherwise, the exogenous product, killed amastigotes with an EC{sub 50} of 0.67mM. These data could be of help in the development of alternative therapeutic approaches to the treatment of leishmaniasis. (author)

  15. Development of an analytical model for the determination of {sup 60}Co in aqueous samples by atomic absorption and gamma spectrometry techniques; Elaboracion de un modelo analitico para la determinacion de {sup 60}Co en muestras acuosas mediante tecnicas de absorcion atomica y espectrometria gamma

    Energy Technology Data Exchange (ETDEWEB)

    Solis A, N. A.

    2015-07-01

    The applications of the nuclear energy in industry and medicine generate radioactive wastes that must be isolated and confined in order to limit its spread in the biosphere. These types of wastes are generated in hospitals, industry, research centers and nuclear power plants (during de fuel cycle). The radioactive elements (radionuclides) cannot be destroyed by any known method, either chemical or mechanical. Its final destruction is produced by radioactive decay, which makes them stable isotopes, or nuclear transmutation being bombarded with atomic particles. Consequently, the radioactive waste management is to control the radioactive discharges and reduce to tolerable limits, eliminating of effluents and wastes the radionuclides of interest, concentrating them so they can be stored or evacuated so that later not appear in dangerous concentration in the biosphere. In Mexico, the main generators of radioactive wastes are the nuclear power plant of Laguna Verde in Veracruz, Hospitals of the public and private sector, in addition Instituto Nacional de Investigaciones Nucleares (ININ) some institutes and facilities of the UNAM and Instituto Politecnico Nacional (IPN) and industries among others. The aqueous radioactive wastes, particularly those from the nuclear power plants contain traces of cobalt-60. Currently there is no model or analytical technique for the separation of this radionuclide, so it became necessary to develop an analytical model for separation and facilitate their disposal. In this paper was shown that atomic absorption and gamma spectrometry techniques can separate the active concentration of the inactive, which is important because the total concentration can be associated through direct relationships with the wear of metal parts of the nuclear reactor, since the metal alloys of the same reactor containing a fraction of cobalt. Also this analytical and mathematical model that can be reproducible and applicable to full sets of samples and that this

  16. A comparison of pdd for 60Co teletherapy units

    International Nuclear Information System (INIS)

    Although BJR supplement No 17 provides TAR and PDD tables for 60Co gamma rays, due to inherent differences hat exists among individual teletherapy machine and their source it is essential to measure TAR and PDD that are applicable for user's teletherapy unit. TAR and PDD values for different field sizes at 80 cm SSD, open field, gantry angle 0o, collimator angle 0o were determined in CIRUS 60Co teletherapy unit by ionization chamber NE2570/1B Farmer type. PDD for a standard field size 10 10 cm2, open field, gantry angle 0o,Collimate angle 0o were determined in MEDNIF FYC 2600H 60Co teletherapy unit by using ionization chamber RT101. That experimentally measured PDD values for both units were compared with published values in BJR supplement No 17. The experimentally measured values for CIRUS 60Co showed up to 0.8% deviation at maximum and that for MEDNIF 60Co showed up to 4.5% deviation at maximum. This study investigated the discrepancy between the BJR values and experimentally determined values for two teletherapy units in Nepal

  17. Dose Rate Effects on The Radiation Oxidation of Polyethylene: Electron Beam vs Gamma Irradiation

    International Nuclear Information System (INIS)

    The yields and spatial distribution of the oxidation products stemming from the oxidation of LLPE films induced by 60-Co gamma and by irradiation with 300 kev, 0.3 mA electrons in the dose range 0.04 kGy/h - 0.6 kGy/h (gamma) and at 1.5 kGy/hr ( e-beam) have been determined by applying a methodology involving FTIR microscopy (carbonyl products, resolution 10 μ), iodometric analysis (peroxides). The FTIR and EPR spectroscopies coupled with the multilayer technique (resolution 25 μ) were also employed for carrying on measurements of the film depth profiles of peroxyl radicals and their alky radicals precursors, radical decay kinetics, 'free' and ' bound' hydroperoxides and alcools. With gamma radiations the products yields are enhanced following the decrease of the dose rate from 0.7 to 0.04 kGy/h without substantial effect on the film depth distributions which appear rather uniform. Using e-beam (dose rate 1.5 kGy/h) a low level concentration limit is attained confined within the first 50 μ which is about 1 order of magnitude smaller as compared to gamma. The mechanistic implications inherent to the experimental results as well as the practical consequences related to the use of radiooxidation as a tool for inducing graft copolymerization reactions are discussed

  18. Gamma Irradiation Facility at Sandia National Laboratories, Albuquerque, New Mexico. Final environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The US Department of Energy (DOE) has prepared an environmental assessment (EA) on the proposed construction and operation of a new Gamma Irradiation Facility (GIF) at Sandia National Laboratories/New Mexico (SNL/NM). This facility is needed to: enhance capabilities to assure technical excellence in nuclear weapon radiation environments testing, component development, and certification; comply with all applicable ES and H safeguards, standards, policies, and regulations; reduce personnel radiological exposure to comply with ALARA limits in accordance with DOE orders and standards; consolidate major gamma ray sources into a central, secured area; and reduce operational risks associated with operation of the GIF and LICA in their present locations. This proposed action provides for the design, construction, and operation of a new GIF located within TA V and the removal of the existing GIF and Low Intensity Cobalt Array (LICA). The proposed action includes potential demolition of the gamma shield walls and removal of equipment in the existing GIF and LICA. The shielding pool used by the existing GIF will remain as part of the ACRR facility. Transportation of the existing {sup 60}Co sources from the existing LICA and GIF to the new facility is also included in the proposed action. Relocation of the gamma sources to the new GIF will be accomplished by similar techniques to those used to install the sources originally.

  19. Gamma Irradiation Facility at Sandia National Laboratories, Albuquerque, New Mexico. Final environmental assessment

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) has prepared an environmental assessment (EA) on the proposed construction and operation of a new Gamma Irradiation Facility (GIF) at Sandia National Laboratories/New Mexico (SNL/NM). This facility is needed to: enhance capabilities to assure technical excellence in nuclear weapon radiation environments testing, component development, and certification; comply with all applicable ES and H safeguards, standards, policies, and regulations; reduce personnel radiological exposure to comply with ALARA limits in accordance with DOE orders and standards; consolidate major gamma ray sources into a central, secured area; and reduce operational risks associated with operation of the GIF and LICA in their present locations. This proposed action provides for the design, construction, and operation of a new GIF located within TA V and the removal of the existing GIF and Low Intensity Cobalt Array (LICA). The proposed action includes potential demolition of the gamma shield walls and removal of equipment in the existing GIF and LICA. The shielding pool used by the existing GIF will remain as part of the ACRR facility. Transportation of the existing 60Co sources from the existing LICA and GIF to the new facility is also included in the proposed action. Relocation of the gamma sources to the new GIF will be accomplished by similar techniques to those used to install the sources originally

  20. Inactive Doses and Protein Concentration of Gamma Irradiated Yersinia Enterocolitica

    International Nuclear Information System (INIS)

    Yersinia enterocolitica is one of bacteria which cause coliform mastitis in dairy cows. The bacteria could be inactivated by gamma irradiation as inactivated vaccine candidate. The experiment has been conducted to determine the inactive doses and the protein concentration of Yersinia enterocolitica Y3 which has been irradiated by gamma rays. The cells cultures were irradiated by gamma rays with doses of 0, 100, 200, 400, 600, 800, 1.000 and 1.500 Gy (doses rate was 1089,59 Gy/hours). The inactive dose was determined by the drop test method and the protein concentration of cells were determined by Lowry method. The results showed that the inactive doses occurred on 800 – 1500 Gy. The different irradiation doses of cell cultures showed the effect of gamma irradiation on the protein concentration that was random and has a significant effect on the protein concentration. (author)

  1. Photosynthetic activity and distribution of photoassimilated 14C in seedlings of zea mays grown from gamma-irradiated seeds

    International Nuclear Information System (INIS)

    The effect of 60Co gamma radiation in doses of 2 and 10 Gy on maize seeds was investigated in four experiments (October 1978 - March 1979). After 3 d germination, an increase in root length and shoot length of 17 and 30%, respectively, was observed for 2 Gy. In the four-leaf stage the plant height and the dry matter weight of shoots were increased by 22 and 17%, respectively, with both doses. At this time the net photosynthetic rate was remarkably higher in seedlings grown from irradiated seeds, but in the same degree for older and younger leaves. 14C distribution in the plants, measured 1 d after 14CO2 exposure indicated that after irradiation a larger part of photosynthates remained in the leaves strengthening the leaf growth, while a smaller part (related to the control plants) was translocated to the roots. The effect of irradiation may be similar to growth stimulation with short time water stress. (author)

  2. The effect of gamma irradiation on the microbiological analysis on commercial functional Brazilian green banana flour

    Energy Technology Data Exchange (ETDEWEB)

    Taipina, Magda S.; Lamardo, Leda C.A.; Santos, Josefina S.; Silva Junior, Eneo A. da [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Balian, Simone C., E-mail: balian@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Fac. de Medicina Veterinaria e Zootecnia

    2011-07-01

    In Brazil, although it is qualified as a major world producers, however, the production losses are high. Nevertheless, these losses can be reduced by processing the fruit 'unsuitable' for consumption into products based on green banana (pulp, rind and flour). The green banana flour shows enhanced nutrition value, with higher contents of mineral, dietary fiber, resistant starch, and total phenolics, for use in Brazilian irradiated ready - to eat foods, such as bread, macaroni, among others. Food irradiation has been identified as safe technology to reduce risk of foodborne illness as part of high-quality food production, processing, handling and preparation. Food irradiation utilizes a source of ionizing energy that passes through food to destroy harmful bacteria and other organisms. Often referred to as 'cold pasteurization', food irradiation offers negligible loss of nutrients or sensory qualities in food as it does not substantially raise the temperature of the food during processing. The object of this work was to determine the effect of gamma irradiation on microbiological analyses of the: the number of mesophiles, total coliforms at 35 deg C, coliforms at 45 deg C, Staphylococcus aureus and Salmonella spp of the green banana flour, commercially found in the Brazilian market. The microbiological analyses were carried out in conformity with the methodologies described at the Faculty of Veterinary Medicine, according to the current legislation. Irradiation was performed in a {sup 60}Co Gammacell 220 (AECL) source, with dose of 3kGy at IPEN/CNEN-SP. In samples of Brazilian green banana flour, irradiated at 3 kGy, the growth of all microorganisms (mesophiles, total coliforms at 35 deg C, coliform at 45 deg C and Staphylococcus coagulase positive) were reduced. As a result, the application of the irradiation technique may be recommended to enhance the food safety. (author)

  3. The effect of gamma irradiation on the microbiological analysis on commercial functional Brazilian green banana flour

    International Nuclear Information System (INIS)

    In Brazil, although it is qualified as a major world producers, however, the production losses are high. Nevertheless, these losses can be reduced by processing the fruit 'unsuitable' for consumption into products based on green banana (pulp, rind and flour). The green banana flour shows enhanced nutrition value, with higher contents of mineral, dietary fiber, resistant starch, and total phenolics, for use in Brazilian irradiated ready - to eat foods, such as bread, macaroni, among others. Food irradiation has been identified as safe technology to reduce risk of foodborne illness as part of high-quality food production, processing, handling and preparation. Food irradiation utilizes a source of ionizing energy that passes through food to destroy harmful bacteria and other organisms. Often referred to as 'cold pasteurization', food irradiation offers negligible loss of nutrients or sensory qualities in food as it does not substantially raise the temperature of the food during processing. The object of this work was to determine the effect of gamma irradiation on microbiological analyses of the: the number of mesophiles, total coliforms at 35 deg C, coliforms at 45 deg C, Staphylococcus aureus and Salmonella spp of the green banana flour, commercially found in the Brazilian market. The microbiological analyses were carried out in conformity with the methodologies described at the Faculty of Veterinary Medicine, according to the current legislation. Irradiation was performed in a 60Co Gammacell 220 (AECL) source, with dose of 3kGy at IPEN/CNEN-SP. In samples of Brazilian green banana flour, irradiated at 3 kGy, the growth of all microorganisms (mesophiles, total coliforms at 35 deg C, coliform at 45 deg C and Staphylococcus coagulase positive) were reduced. As a result, the application of the irradiation technique may be recommended to enhance the food safety. (author)

  4. Effects of gamma irradiation on antioxidants of medicinal plants

    International Nuclear Information System (INIS)

    The antioxidant effect of water extracts from irradiated medicinal plants on inhibition of lipid peroxidation in human plasma was examined. The results presented herein indicate that crude extracts from 29 kinds, 31 extracts, of medicinal plants, irradiated at 10 and 25 kilo gray. showed no significant change in inhibition of lipid peroxidation in plasma induced by gamma irradiation (p<0.05). It also found that extraction yields in some irradiated plants were increased

  5. Effect of gamma irradiation at intermediate doses on the performance of reverse osmosis membranes

    Science.gov (United States)

    Combernoux, Nicolas; Labed, Véronique; Schrive, Luc; Wyart, Yvan; Carretier, Emilie; Moulin, Philippe

    2016-07-01

    The goal of this study is to explain the degradation of Polyamide (PA) composite reverse osmosis membrane (RO) in function of the irradiation dose. Irradiations were performed with a gamma 60Co source in wet conditions and under oxygen atmosphere. For different doses of 0.2 and 0.5 MGy with a constant dose rate of 0.5 kGy h-1, RO membranes performances (NaCl retention, permeability) were studied before and after irradiation. ATR-FTIR, ion chromatography and gas chromatography were used to characterize structural modification. Results showed that the permeability of RO membranes irradiated at 0.2 MGy exhibited a small decrease, related to scissions of the PVA coating. However, retention did not change at this dose. At 0.5 MGy, permeability showed a large increase of a factor around 2 and retention began to decrease from 99% to 95%. Chromatography measurements revealed a strong link between permselectivity properties variation, ion leakage and oxygen consumption. Add to ATR-FTIR observations, these results emphasized that the cleavages of amide and ester bonds were observed at 0.5 MGy, more precisely the loss of hydrogen bonds between polyamide chains. By different analysis, modifications of the polysulfone layer occur until a dose of 0.2 MGy.

  6. Effect of gamma ray irradiation on the structural and electrical transport properties of PrFe{sub 1−x}Mn{sub x}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Sultan, Khalid, E-mail: ksbhat.phy@gmail.com; Ikram, M., E-mail: ksbhat.phy@gmail.com [Department of Physics, National Institute of Technology Hazratbal, Srinagar-190006, Jammu and Kashmir (India); Asokan, K. [Material Science Division, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi-110067 (India)

    2014-04-24

    The effect of gamma ray irradiation on the structural and transport properties of polycrystalline bulk samples of PrFe{sub 1−x}Mn{sub x}O{sub 3} (x = 0.0, 0.1, 0.5) were investigated. The samples were synthesized by solid state reaction method and exposed to {sup 60}Co gamma radiation to accumulated dose of 625 KGy. From the Raman study, the modes exhibit a blue shift with broadening of spectral features in the irradiated samples. The dielectric constant (ε′) was also studied as a function of frequency. The dielectric constant and ac conductivity increases with Mn doping but decrease on irradiation. Exposure to gamma radiation results in substantial modification in the physical properties of these compounds.

  7. Effect of gamma irradiation on storability of strawberry (Fragaria sp)

    International Nuclear Information System (INIS)

    Despite the increased production of strawberry in Syria, the storability and marketability of fruits were not well studied. The objectives of this study were to investigate the effect of gamma irradiation on storability of Senga sengana strawberry produced in Syria and the effect of gamma irradiation on fungal sp. i.e. Botrytis; Penicillium; Rhizopus. The fruits were treated with 1 , 2 and 3 KGy of gamma rays. Treated and untreated fruits were stored at 2 to 4 centigrade and 80 to 90 % relative humidity (RH). In order to investigate their marketability, the fruits where held at room temperature (25 to 30 centigrade). Weight loss, microbial decay, and total loss, juice production, pH, total soluble solids of the juice and organoleptic qualities were evaluated throughout the different storage and marketing periods. The results indicate that gamma irradiation decreased the microbial decay and increased the storability and marketability of fruits by 50 and 100% after using 2 and 3 kGy, respectively. D10 were 1.8 and 2.4 for Botrytis and Rhizopus respectively. One day after irradiation total soluble solids and its pH values were increased. Fourteen days later, irradiated fruits produced more juice with higher pH, but total soluble solids were less. Gamma irradiation did not have an effect on aroma and colour of fruits, whereas, 3 kGy of gamma irradiation had an adverse negative effect on taste. (author)

  8. Glucose metabolism in gamma-irradiated rice seeds

    International Nuclear Information System (INIS)

    Gamma-irradiation of 30 kR in rice seeds caused marked inhibition in seedling growth, and prevented the release of reduced sugar during the period of 25 to 76hr after soaking. The C6/C1 ratio following irradiation continued to decrease up to the 76th hour of soaking; the control's ratio tended to increase with comparable soaking time. The percentage recovery of 14C in carbon dioxide from glucose -1-14C was lower in irradiated than in control seeds. These results indicate that gamma-irradiation reduces the participation of the pentose phosphate pathway in glucose catabolism during an early period of germination. (author)

  9. EPR study on gamma-irradiated fruits dehydrated via osmosis

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, N.D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)]. E-mail: ndyepr@bas.bg; Aleksieva, K. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2007-06-15

    The shape and time stability of the electron paramagnetic resonance (EPR) spectra of non- and {gamma}-irradiated papaya, melon, cherry and fig samples dehydrated via osmosis are reported. It is shown that non-irradiated samples are generally EPR silent whereas {gamma}-irradiated exhibit 'sugar-like' EPR spectra. The recorded EPR spectra are monitored for a period of 7 months after irradiation (stored at low humidity and in the dark). The results suggest longer period of unambiguous identification of the radiation processing of osmose dehydrated fruits. Therefore, the Protocol EN 13708,2001 issued by CEN is fully applicable for the studied fruit samples.

  10. Study of the {sup 60}Co speciation in the aqueous radioactive waste of the la Hague nuclear reprocessing plant; environmental behaviour after discharges in the waters of the channel; Etude de la speciation du {sup 60}Co dans les effluents de l'usine de retraitement de combustibles irradies de la Hague; devenir apres rejet dans les eaux de la Manche

    Energy Technology Data Exchange (ETDEWEB)

    Gaudaire, J.M

    1999-07-01

    {sup 60}Co is produced as an activation product and is present in the low-level aqueous radioactive waste released from the La Hague plant. At present, the concentration in the sea (non filtered at 0.45 {mu}m) at the Goury site are close to or even below, the detection limit: 0.2 mBq.l{sup -1}. The {sup 60}Co speciation depends on the type of effluent considered: in the effluent A ('active'), the cobalt is in the form of a stable trivalent complex; in the effluent V (to be checked), the cobalt is in majority (50% of the activity release) in the form of particles (>0.45 {mu}m), and then in the form of two soluble species: ionic divalent (Co{sup 2+}) and some stable complexes. The evolution of the reprocessing techniques used does not affect the speciation. So, since the nuclear reprocessing plant started at the La Hague plant in 1966, the chemical species discharged in the sea shows time variation related to the evolution of the type of effluent discharged. Thus, since 1994, the particles of cobalt are the main species discharged in the Channel (the V effluents represent more than 85% of the total {sup 60}Co activity released). The effect of instantaneous dilution into the marine conditions involving a variation of pH, oxido-reduction, ionic strength, a gradient of salinity, does not interfere with the evolution of the chemical species discharged. Nevertheless, during the discharge of the V effluent, the main constituents of the sea water (Mg{sup 2+} and Ca{sup 2+}) go through a precipitation. This comes with the coprecipitation of the ion Co{sup 2+} and with the particles of cobalt (complexes are not affected), and it can be responsible for an increase in the concentration in the particles. The chemical behaviour of the cobalt in the Channel is different from those of conservative element such as antimony. The ionic cobalt and the particles have a small dispersion in the water (cobalt has a very high particle/dissolved distribution factor, it is a non

  11. Effect of gamma irradiation on some characteristics of shell eggs and mayonnaise prepared from irradiated eggs

    International Nuclear Information System (INIS)

    Shell eggs were irradiated at doses of 0.0, 0,5, 1.0 and 1.5 kGy of gamma irradiation. Immediately after irradiation, microbiological, physical and chemical analyses of eggs and sensory evaluation of mayonnaise prepared from irradiated eggs were done. The results indicated that all doses of gamma irradiation reduced the total counts of mesophilic bacteria and total coli form of yolk eggs. Irradiated eggs with 1.5 kGy maybe suitable microbiologically to prepare safe mayonnaise. There are no significant differences on saturated fatty acids and TBA values between yolk fat extracted from irradiated and that of non-irradiated eggs. Sensory evaluation showed no significant differences between mayonnaise prepared from irradiated and non-irradiated eggs. (Author)

  12. Physico-chemical characterization of gamma rays irradiated crotamine

    International Nuclear Information System (INIS)

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. It has been employed to attenuate animal toxins. Crotamine, a toxin from Crotalus durissus terrificus (Cdt), is a highly basic polypeptide (pI - 10.3), with myotoxic activity and molecular weight of 4882 Da. It is composed of 42 amino acids residues and reticulated by three disulfide bonds. This study aimed the characterization of irradiated crotamine using Circular Dichroism (CD), Fluorescence Spectroscopy and Differential Scanning Calorimetry (DSC) techniques. We used size exclusion and ion-exchange chromatography to purify it from Cdt crude venom. The pure crotamine was irradiated with 2.0 kGy from a 60Co source. Native and irradiated crotamine were analyzed in a fluorescence spectrophotometer (Hitachi F-4500), under excitation wavelength at 275 nm and the emission was scanned from 300 to 500 nm. The analysis of fluorescence quenching showed that the irradiated form displayed a lower quantum yield when compared to the native form. CD spectra, obtained from a Jasco, J-180 spectropolarimeter, of native and irradiated crotamine solutions, showed a discrete change between the samples, from apparently ordered conformation to a random coil. Finally, the thermodynamics analysis, realized in a calorimeter METTLER TOLEDO, DSC 822e, showed that irradiation promoted changes in the calorimetric profile. Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain the decrease in myotoxic activity. (author)

  13. 60Co levels in the seawater regions

    International Nuclear Information System (INIS)

    In order to assess the contribution from nuclear power facilities to the 60Co levels in seawater regions, it is essential to grasp the background values of 60Co. The following matters are described: 60Co sources and the respective inputs; nuclear test fallout and nuclear power plants; the 60Co levels in overseas countries; the 60Co levels in Japan; the 60Co levels from nuclear power plants in Fukui prefecture. In the seawater regions around Japan, there have been numerous instances of 60Co detection; several pCi/kg of dry earth in sea bottom earth and about 1 pCi/kg of raw material in marine life can be considered as the background levels due to nuclear test fallout and nuclear-powered submarines. In the seawater regions of Fukui prefecture, the 60Co levels appreciably exceeded the above background due to the nuclear power plants, which are insignificant concerning the radiation exposure of the local people. (Mori, K.)

  14. Introduction of gamma irradiation Center in Iran

    International Nuclear Information System (INIS)

    Industrial sterilization, and especially radiation sterilization, of single use, disposable medical supplies are contributing significantly to health standards in each country. Today there are in excess of 135 plants around the world using gamma radiation by more than 90 million curies of cobalt-60 to sterilize single use medical products. This process in far superior to other methods of sterilization, some of the advantages of this process include its basic simplicity compared with thermal or chemical methods. In the former process only a single variable of time is controlled while for the latter processes five or six parameters such as time, temperature, pressure, humidity, concentration, type of cover etc. need to be monitored. Compared with the chemical method, irradiation technique is also free from the environmental hazards associated with the exhausting of the, often carcinogenic sterilizing agent. United Nation Development Programs (UNDP) and International Atomic Energy Agency (IAEA) have, through financial and technical support, promoted the introduction of radiation sterilization in several developing countries. This centre is also being established in Iran through UNDP financial and IAEA technical assistance. Although the main task of this centre is to radiosterilize the disposable medical products, but the scope of activities also encompass investigation of processing techniques of various products as well as research and development in the related fields. (Author)

  15. Characterization of Brazilian mango kernel fat before and after gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Aquino, Fabiana da Silva; Ramos, Clecio Souza, E-mail: fasiaquino@yahoo.com.br, E-mail: clecio@dcm.ufrpe.br [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil); Aquino, Katia Aparecida da Silva, E-mail: aquino@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2013-07-01

    Mangifera indica Linn (family of Anacardiaceae) is a tree indigenous to India, whose both unripe and ripe fruits (mangoes) are widely used by the local population. After consumption or industrial processing of the fruits, considerable amounts of mango seeds are discarded as waste. The kernel inside the seed represents from 45% to 75% of the seed and about 20% of the whole fruit and lipid composition of mango seed kernels has attracted the attention of researches because of their unique physical and chemical characteristics. Our study showed that fat of the mango kernel obtained by Soxhlet extraction with hexane had a solid consistency at environmental temperature (27 deg C) because it is rich in saturated acid. The fat contents of the seed of Mangifera indica was calculated to 10% and are comparable to the ones for commercial vegetable oils like soybean (11-25%). One problem found in the storage of fast and oils is the attack by microorganisms and the sterilization process becomes necessary. Samples of kernel fat were irradiated with gamma radiation ({sup 60}Co) at room temperature and air atmosphere at 5 and 10 kGy (sterilization doses). The data of GC-MS analysis revealed the presence of four major fatty acids in the sample of mango kernel examined and that the chemical profile of the sample not altered after being irradiated. Moreover, analysis of Proton Nuclear Magnetic Resonance (NMR H{sup 1}) was used to obtain the mango kernel fat parameters before and after gamma irradiation. The data interpretation of RMN H{sup 1} indicated that there are significant differences in the acidity and saponification indexes of fat. However, it was found an increase of 14% in iodine index of fat after irradiation. This result means that some double bonds were formed on the irradiation process of the fat. (author)

  16. Characterization of Brazilian mango kernel fat before and after gamma irradiation

    International Nuclear Information System (INIS)

    Mangifera indica Linn (family of Anacardiaceae) is a tree indigenous to India, whose both unripe and ripe fruits (mangoes) are widely used by the local population. After consumption or industrial processing of the fruits, considerable amounts of mango seeds are discarded as waste. The kernel inside the seed represents from 45% to 75% of the seed and about 20% of the whole fruit and lipid composition of mango seed kernels has attracted the attention of researches because of their unique physical and chemical characteristics. Our study showed that fat of the mango kernel obtained by Soxhlet extraction with hexane had a solid consistency at environmental temperature (27 deg C) because it is rich in saturated acid. The fat contents of the seed of Mangifera indica was calculated to 10% and are comparable to the ones for commercial vegetable oils like soybean (11-25%). One problem found in the storage of fast and oils is the attack by microorganisms and the sterilization process becomes necessary. Samples of kernel fat were irradiated with gamma radiation (60Co) at room temperature and air atmosphere at 5 and 10 kGy (sterilization doses). The data of GC-MS analysis revealed the presence of four major fatty acids in the sample of mango kernel examined and that the chemical profile of the sample not altered after being irradiated. Moreover, analysis of Proton Nuclear Magnetic Resonance (NMR H1) was used to obtain the mango kernel fat parameters before and after gamma irradiation. The data interpretation of RMN H1 indicated that there are significant differences in the acidity and saponification indexes of fat. However, it was found an increase of 14% in iodine index of fat after irradiation. This result means that some double bonds were formed on the irradiation process of the fat. (author)

  17. Gamma irradiation influence on physical properties of milk proteins

    Science.gov (United States)

    Cieśla, K.; Salmieri, S.; Lacroix, M.; Tien, C. Le

    2004-09-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and β-sheets, in particular from increase of β-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

  18. Gamma irradiation influence on physical properties of milk proteins

    International Nuclear Information System (INIS)

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and β-sheets, in particular from increase of β-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling

  19. Gamma irradiation versus microbial contamination of Thai medicinal herbs

    Directory of Open Access Journals (Sweden)

    Wannipa Phianphak

    2007-03-01

    Full Text Available Seventeen species of herbs established in Thai traditional remedies were microbially decontaminated by gamma-irradiation doses of 7.7 and 8.8 kGy. The herb samples were randomly collected four times from producers in Chiangmai during a 1-year period. These were tested, qualitatively and quantitatively, for total aerobic bacteria, Staphylococcus spp., Salmonella spp., coliform bacteria, and fungi before and after gamma treatment. No microorganisms were found after gamma treatment; and the color, aroma, and texture of the herbs remained normal. The applied dose of gamma irradiation was within the regulatory limits in Thailand (<10 kGy and the main export country (USA< 30 kGy. Gamma irradiation is an effective treatment for microbial decontamination of Thai export herbs.

  20. DNA repair after gamma irradiation in lymphocytes exposed to low-frequency pulsed electromagnetic fields

    International Nuclear Information System (INIS)

    The effect of exposure to extremely low-frequency pulsed electromagnetic fields (EMFs) on DNA repair capability and on cell survival in human lymphocytes damaged in vitro with gamma rays was studied by two different micromethods. In the first assay, which measures DNA repair synthesis (unscheduled DNA synthesis, UDS), lymphocyte cultures were stimulated with phytohemagglutinin (PHA) for 66 h and then treated with hydroxyurea (which blocks DNA replication), irradiated with 100 Gy of 60Co, pulsed with [3H]thymidine ([3H]TdR), and then exposed to pulsed EMFs for 6 h (the period in which cells repaired DNA damage). In the second assay, which measures cell survival after radiation or chemical damage, lymphocytes were first irradiated with graded doses of gamma rays or treated with diverse antiproliferative agents, and then stimulated with PHA, cultured for 72 h, and pulsed with [3H]TdR for the last 6 h of culture. In this case, immediately after the damage induced by either the radiation or chemicals, cultures were exposed to pulsed EMFs for 72 h, during which cell proliferation took place. Exposure to pulsed EMFs did not affect either UDS or cell survival, suggesting that this type of nonionizing radiation--to which humans may be exposed in the environment, and which is used for both diagnostic and therapeutic purposes--does not affect DNA repair mechanisms

  1. Gamma irradiation reduces the immunological toxicity of doxorubicin, anticancer drug

    International Nuclear Information System (INIS)

    Doxorubicin (DOX) is a widely used anticancer agent, but exhibits some immunological toxicity to patients during chemotherapy. The present study was conducted to evaluate the effect of gamma irradiation on the immunological response and the inhibition activity on in vivo tumor mass of DOX. The results showed that DOX irradiated at 10 and 20 kGy reduce the inhibition of mouse peritoneal macrophage proliferation and induce the release of cytokines (TNF-α and IL-6) when compared with non-irradiated DOX. The cytotoxicity against human breast (MCF-7), murine colon adenocarcinoma (Colon 26) and human monocytic (THP-1) tumor cell were not significantly different between non-irradiated and irradiated DOX (P<0.05). In vivo study on the tumor mass inhibition, gamma-irradiated DOX showed a considerable inhibition of tumor mass and this effect was statistically non-significant as compared with non-irradiated DOX. In conclusion, gamma irradiation could be regarded as a potential method for reducing the immunological toxicity of DOX. Further researches is needed to reveal the formation and activity of radiolysis products by gamma irradiation.

  2. Safer prepared meals for immunocompromised patients and the general consumer by gamma irradiation

    International Nuclear Information System (INIS)

    Ready-to-eat meals are commonplace nowadays in urban life. Many of them, minimally processed, could convey foodborne pathogens likely to cause diseases in the consumer, which is of concern to the normal population and even more so to immunocompromised patients. The feasibility of attaining microbiological decontamination at pasteurization levels of such foods by gamma irradiation was studied. Typical Argentine dishes were chosen after market surveys: cannelloni in tomato sauce, tomato and carrot salad with boiled egg, empanada, fruit salad in gelatin jelly with white cheese, ham and cheese sandwich, chicken and vegetable pie, custard, and bread pudding, in different packaging. Microbiological profiles of the meals were obtained and challenge tests with Listeria innocua or Salmonella enteritidis were performed to determine the minimum radiation dose to be applied in each food so as to attain a 6 log cycle reduction of pathogen counts. Preliminary sensory evaluations, out of panel, were carried out to determine possible evident sensory alterations due to the irradiation treatment. Then, a greater number of samples were irradiated at the minimum radiation dose and at a maximum dose equal to or less than twice the minimum, at the 60Co semi-industrial facility of the Ezeiza Atomic Center. Microbiological and sensory analyses by a consumer panel were performed on control and irradiated samples throughout storage life at refrigeration temperatures. A whole irradiated lunch, composed of salad, empanadas and fruit salad, was sampled by 44 immunocompromised patients at a hospital. The composition and adequacy of this lunch was designed by nutritionists. Results showed that it was feasible to attain the proposed decontamination goal without significantly impairing the sensory quality. Shelf life was almost tripled in irradiated samples. Immunocompromised patients enjoyed the irradiated lunch and requested it and other dishes to be made commercially available. (author)

  3. Effects of gamma irradiation on the initial mechanical and material properties of goat bone-patellar tendon-bone allografts

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, M.J.; Butler, D.L.; Grood, E.S.; Bylski-Austrow, D.I.; Levy, M.S.; Noyes, F.R. (Univ. of Cincinnati, OH (USA))

    1991-03-01

    The effects of {sup 60}Co gamma irradiation on the initial mechanical properties of the composite bone-patellar tendon-bone unit (CU) and the tendon midsubstance (TM) were studied. Frozen specimens were exposed to either 2 or 3 Mrad of gamma irradiation. Paired frozen specimens served as intraanimal controls. Treatment effects on the CU were assessed using four mechanical parameters. Effects on the TM were assessed using four material parameters measured using an optical surface-strain analysis system. The maximum force and strain energy to maximum force of the composite unit were significantly reduced 27% and 40%, respectively, after 3 Mrad of irradiation (p less than .05). Mechanical properties of the CU were not significantly altered, however, following 2 Mrad of irradiation. Based on individual paired contrasts between treatment and control, significant differences were also found in the material properties of the tendon midsubstance. The maximum stress, maximum strain, and strain energy density to maximum stress were significantly reduced following 3 Mrad, but not 2 Mrad, of irradiation. The results provide important time zero material property data, which will be useful for later anterior cruciate ligament reconstruction studies using irradiated allograft patellar tendons in the goat model and other animal models as well.

  4. Effect of gamma irradiation on microbial load, chemical and sensory properties of chicken kabab and sausage; as prepared chilled meals

    International Nuclear Information System (INIS)

    Chicken kabab and sausage were treated with 0, 2, 4 or 6 kGy doses of gamma irradiation in a 60CO package irradiator. Treated and untreated samples were kept in a refrigerator (1-4 degree centigrade). Microbiological, chemical and sensory characteristics of chicken kabab and sausage were evaluated at 0, 1, 2, 3, 4, and 5 months of storage. Proximate composition and sensory evaluation of the chicken kabab and sausage were also investigated, but only immediately after treatment. Irradiation did not influence the major constituents of chicken kabab and sausage (moisture, protein and fats). Gamma irradiation decreased the microbial load and increased the shelf-life of chicken kabab and sausage. The dose needed to decrease by 1 log cfu/g (D10 value) of Salmonella spp and E coli. numbers were 213 and 400 Gy in chicken kabab, while 345 and 250 Gy in chicken sausage, respectively. The chemical parameters, total acidity, volatile basic nitrogen (VBN), and thiobarbituric acid reactive substances (TBARS), which were chosen as the indices of freshness, were all well within the acceptable limit for up to 5 months for chicken kabab and sausage treated with 4 and 6 kGy. Sensory evaluation showed no significant differences between irradiated and non-irradiated samples. (author)

  5. Application of gamma-irradiation to cereals and cereals products

    International Nuclear Information System (INIS)

    Gamma-irradiation may be used on cereals and cereal products to control insect infestation and microbiological problems. Such problems include mould growth, mycotoxin production, pathogens, spore-forming organisms and total microbial load. Deleterious effects of gamma-irradiation arise only at relatively high dose levels with consequences on germination rate, wheat flour dough properties, and cake and noodle quality. Radiation-induced changes to starch have greater impact on behaviour of cereal products than such changes to other cereal components

  6. Sprout inhibition in garlic (Allium sativum) and onion (Allium cepa L.) by gamma irradiation. Part of a coordinated programme on pre-commercial scale radiation treatment of food

    International Nuclear Information System (INIS)

    With the aim of verifying the possibilities and circumstances of sprout inhibition and storage life extension of onion and garlic by gamma irradiation, onion bulbs of variety Valenciana Sintetica 14 and garlic bulbs of a coloured locally grown variety were subjected to irradiation with 3 Krad of 60Co gamma rays. The dose rate was 2440 rad/min; the irradiation conditions warranted a Dsub(max)/Dsub(min) ratio of 1.25. The irradiated bulbs and control samples of non-irradiated bulbs were investigated for a period of 270 to 330 days. Weight loss, external and internal sprouting, signs of decay, and the percentage of commercial bulbs were observed with the following results. Weight loss was found to be less in irradiated bulbs than in controls - 22% against 40% for onion and 33% against 65% for garlic. The dose of gamma radiation employed was proved to be sufficient for sprout inhibition in both species and for partial inhibition of decay and softening. The aroma of garlic was not impaired by irradiation. For both products, gamma irradiation was found to prolong the period of commercial utilizability

  7. Catalytic properties of testicular hyaluronidase after gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, P.K.; Gupta, G.S.

    1986-08-01

    The effect of gamma-irradiation on ovine testicular hyaluronidase was studied in aqueous solution. Following irradiation, hyaluronidase is inhibited, and the kinetics of inhibition follow a pattern in which Ksub(m) and Vsub(max) decline as radiation dose is increased. It was indicated that the binding affinity of the residual activity of hyaluronidase with substrate is enhanced and depends upon radiation damage. Effects of various agents such as pH, salts, PCMB and glutathione on irradiated hyaluronidase have been compared with non-irradiated enzyme. The irradiated hyaluronidase was more sensitive to inhibition by CuSO/sub 4/ than the non-irradiated enzyme. The residual activity after irradiation is less refractory to FeCl/sub 3/ inhibition and less sensitive to NaCl stimulation compared to non-irradiated hyaluronidase. pH response curves of ovine testicular hyaluronidase show two maxima which become more evident after irradiation.

  8. Effect of gamma irradiation on seed germination, growth and biochemical parameters of Terminalia arjuna ROXB

    International Nuclear Information System (INIS)

    Terminalia arjuna, a potent medicinal plant for the treatment of cardiac disease was chosen for the study. About 300 seeds of T. arjuna were irradiated with different doses (0, 10, 25, 50, 100, 150 and 200 Gy) of gamma radiation using 60Co gamma source. Effect of gamma radiation on growth and biochemical constituents were compared with the control of plants. Germination speed at 25 Gy was found to be 0.65 which was double the control plants. An increase in germination percentage, vigour index and relative growth rate in terms of dry weight was noticed at lower dosages. There was a gradual increase in shoot and root length at 25 and 50 Gy which decreased at higher doses of radiation. Proline content increased with increasing doses of radiation. Chlorophyll content was found to be 12.2 mg/gfw at 100 Gy while in control it was 8.44 mg/gfw. Increased phenolic content and radical scavenging capacity was observed at 25 Gy and 150 Gy. Hence, lower doses of radiation treatment to seeds may be recommended to increase the germination, growth and to increase secondary plant products. (author)

  9. Damage correlations in semiconductor devices exposed to gamma and high energy swift heavy ions

    International Nuclear Information System (INIS)

    NPN rf power transistors and N-channel depletion MOSFETs are irradiated by different high energy swift heavy ions and 60Co gamma radiation in the dose range of 100 krad to 100 Mrad. The damage created by different heavy ions and 60Co gamma radiation in NPN rf power transistors and N-channel depletion MOSFETs have been correlated and studied in the same dose range. The recoveries in the electrical characteristics of different swift heavy ions and 60Co gamma irradiated devices have been studied after annihilation

  10. Damage correlations in semiconductor devices exposed to gamma and high energy swift heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Pushpa, N., E-mail: pushpa-gnp@hotmail.com [Department of PG Studies in Physics, JSS College, Ooty Road, Mysore-570025 (India); Prakash, A. P. Gnana [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore-570 006 (India)

    2015-05-15

    NPN rf power transistors and N-channel depletion MOSFETs are irradiated by different high energy swift heavy ions and {sup 60}Co gamma radiation in the dose range of 100 krad to 100 Mrad. The damage created by different heavy ions and {sup 60}Co gamma radiation in NPN rf power transistors and N-channel depletion MOSFETs have been correlated and studied in the same dose range. The recoveries in the electrical characteristics of different swift heavy ions and {sup 60}Co gamma irradiated devices have been studied after annihilation.

  11. Damage correlations in semiconductor devices exposed to gamma and high energy swift heavy ions

    Science.gov (United States)

    Pushpa, N.; Prakash, A. P. Gnana

    2015-05-01

    NPN rf power transistors and N-channel depletion MOSFETs are irradiated by different high energy swift heavy ions and 60Co gamma radiation in the dose range of 100 krad to 100 Mrad. The damage created by different heavy ions and 60Co gamma radiation in NPN rf power transistors and N-channel depletion MOSFETs have been correlated and studied in the same dose range. The recoveries in the electrical characteristics of different swift heavy ions and 60Co gamma irradiated devices have been studied after annihilation.

  12. The effects of gamma irradiation on Gossypium Hirsutum L. Pollen

    International Nuclear Information System (INIS)

    Gossypium Hirsutum L. (cotton) is cultivated widely in Turkey. In this study the seeds of cotton, variety Cukurova 1518 were irradiated at 5, 10, 20, 30, 40 krad doses with 60Co and cytological studies were done in M1 and M2 generations. In M2 generation, the total of the undyed pollen and heteromorph pollen was 0.61% for 5 krad treatment while this value was 1.36 percent in M1 generation. The maximum increase in undyed and heteromorphic (sterile) pollen were observed for 40 krad treatment both for M1 and M2. The percent increases for M1 and M2 were found 10.39% and 7.10% respectively. On the other hand, morphological normal pollens were measured in M1 and pollen largeness was found to be 120.35 μm in control but this value was changed for the irradiated groups

  13. Manual on panoramic gamma irradiators (categories 2 and 4)

    International Nuclear Information System (INIS)

    In addition to a basic guide to the principles of production of ionizing radiation and to the methods of radiation protection and dosimetry, this document considers the procedures that should be employed when using panoramic gamma irradiators. Applications for such irradiators are described and radiation protection procedures discussed

  14. Results on Neutron and Gamma Irradiation of Electrolytic Tilmeters

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, A.; Calvo, E.; Figueroa, C. F.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Vila, I.; Virto, A. L.; Alberdi, J.; Arce, P.; Barcala, J. M.; Fernando, A.; Fuentes, J.; Josa, M. I.; Luque, J. M.; Molinero, A.; Navarrate, J.; Valdivieso, P.; Fenyvesi, A.; Molnar, J.

    2004-07-01

    We report on irradiation studies done to a sample of high precision electrolytic tiltmeters with gamma-rays, up to a maximum dose of 150 kGy, an neutrons, up to a maximum fluence 1.5x10''14 cm''2. The effect of the irradiation on their performance is discussed. (Author) 19 refs.

  15. Effect of gamma irradiation on Hom Tong banana

    International Nuclear Information System (INIS)

    This report contains research on the use of gamma irradiation to retard the ripening and extend the shelf life of bananas. The major concerns were the effects that irradiation would have on the nutritional content, the organoleptic properties and the pigment of the fruit

  16. Investigation of effects of gamma ray irradiation on pyrolysis properties of glove-box panel materials

    International Nuclear Information System (INIS)

    The glove box (GB) is a device with some plastic components and is used for the containment of radioactive materials. In a MOX fuel fabrication facility, MOX is also handled in the GB. Since the plastic panel, which has the largest area in the GB, is used over a long period, it is exposed to a high dose of MOX continuously. In this study, to confirm whether the containment capability of GB can be maintained even under external thermal stress, the effects of gamma ray irradiation with 60Co on the pyrolysis properties of the common panel materials were investigated by TG-DTA. As a result, polymethylmethacrylate showed a large peak of the mass loss rate at about 260 degrees under the nonirradiation and air condition, but it separated into lower and higher temperature sides above 25 kGy. This effect was not observed up to 10 kGy for polymethylmethacrylate and up to 880 kGy for polycarbonate. By comparison with the estimated total dose of the GB panel irradiated in the operation period, it was found that the irradiation from MOX does not significantly affect the pyrolysis properties of the GB panel in the actual facility. (author)

  17. Paramagnetic centers induced by gamma irradiation of bioactive silica glasses containing yttrium

    International Nuclear Information System (INIS)

    Full text: Silica bioactive glasses containing neutron activated yttrium were investigated as a potential material for internal radiotherapy of cancers. The silica glasses, containing yttrium oxide and different alkali and alkaline-earth oxides as network modifiers, were obtained by melt annealing method. The samples were exposed to gamma radiation from a 60Co source for up to 10 days irradiation time. The radiation induced paramagnetic point defects in the irradiated glasses were analysed by Electron Paramagnetic Resonance (EPR). The EPR spectra of the silica glasses with different modifiers are characterised by a resonance line at g ≅ 2.024, slightly varying with the composition, attributed to a non-bridging oxygen hole centres. The addition of modifier oxides into glass network results in the formation of non-bridging oxygens that are locally charged compensated by modifier cations in neighbouring interstitial positions. The presence of small amount of boron oxide, up to 2.6 wt. %, in some of the glasses induced the formation of boron oxygen hole centres that are the main EPR species in these irradiated glasses. The presence of the EPR evidenced defects have to be taken into account as possible centres for glasses dissolution in human body during the radiotherapy procedure. (author)

  18. The effect of the substitution of D{sub 2}O for H{sub 2}O on the degradation of myosin {beta} in solution by heat and by {sup 60}Co {gamma} radiation (1962); Effet de la substitution de D{sub 2}O a H{sub 2}O sur l'alteration de la Myosine B en solution par la chaleur et par les rayons {gamma} du {sup 60}CO (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Pinset-Harstrom, I.; Fritsch, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    (1) Alterations of myosin B produced by heat or irradiation are shown to be qualitatively identical as demonstrated by analytical centrifugation. (2) A considerable isotope effect was demonstrated using 75 per cent D{sub 2}O in the solvent. The sensitivity of myosin B to heat and irradiation is discussed in the light of this isotope effect. (3) Polymers appearing upon heat treatment of myosin B seem to be of a very different nature than the polymers occurring alter a similar treatment upon myosin A. Polymers obtained from myosin B can be depolymerized by ATP and they appear in a much narrower temperature range than myosin A polymers. This fact indicates a considerable difference in the activation enthalpies in the two reactions. (authors) [French] (1) Cette etude montre que les alterations de la myosine B provoquees par la chaleur et par l'irradiation aux rayons {gamma} sont - telles qu'elles apparaissent a l'ultracentrifugation analytique - qualitativement semblables. (2) Nous avons observe un effet isotopique considerable de la presence de 75 pour cent de D{sub 2}O dans le solvant sur la sensibilite de la myosine B envers ces deux agents, et nous avons presente une tentative d'explication de ce fait. (3) Les polymeres qui apparaissent apres un traitement par la chaleur de la myosine semblent etre d'une nature tres differente des polymeres que l'on voit apparaitre apres un traitement identique de la myosine A. Ceux obtenus a partir de le myosine B sont depolymerisables par l'intermediaire de l'ATP et apparaissent dans une zone de temperature beaucoup plus etroite que celles de la myosine A. Ce dernier fait indique une difference considerable de l'enthalpie d'activation des deux reactions. (auteurs)

  19. Radiation protection in category III large gamma irradiators

    International Nuclear Information System (INIS)

    This article discusses the advantages of category III large gamma irradiator compared to the others, with emphasis on aspects of radiological protection, in the industrial sector. This category is a kind of irradiators almost unknown to the regulators authorities and the industrial community, despite its simple construction and greater radiation safety intrinsic to the model, able to maintain an efficiency of productivity comparable to those of category IV. Worldwide, there are installed more than 200 category IV irradiators and there is none of a category III irradiator in operation. In a category III gamma irradiator, the source remains fixed in the bottom of the tank, always shielded by water, negating the exposition risk. Taking into account the benefits in relation to radiation safety, the category III large irradiators are highly recommended for industrial, commercial purposes or scientific research. (author)

  20. 60Co-γ射线辐射对美女樱·菠萝菊根长·芽长及出芽率的影响%Effect of the Treatment with 60Co-γ Ray Irradiation on the Germination Rate and the Length of Bud and Root of Verbena hortensis and Carthamus tinctorius

    Institute of Scientific and Technical Information of China (English)

    吴光升; 强继业; 陈立

    2005-01-01

    对美女樱和菠萝菊种子进行4种剂量的60Co-γ射线处理,结果显示:40Gy的辐射剂量可促进美女樱出芽率,而10、20、80Gy的辐射剂量抑制出芽率.辐射剂量和芽长、根长呈正相关.80Gy辐射剂量对美女樱的出芽率、芽长、根长较适宜.对菠萝菊而言,辐射剂量和出芽率、根长呈负相关.辐照对菠萝菊种子起抑制作用,说明菠萝菊不适合此范围的高剂量辐照.其中辐射剂量为20、80Gy时,菠萝菊种子不发芽;辐射剂量为40 Gy时,芽长达到了4.91 mm,远远大于对照0.57 mm.

  1. Effects of gamma irradiation on raw materials and perfumes

    International Nuclear Information System (INIS)

    In order to enlight the strange problem of apparent perfume stability observed in manufactured talc powders sterilized by gamma rays, investigations were made on samples of odorant substances (raw materials, essential oils, or elaborated mixtures). As a rule, no immediate adulteration of olfactive caracteristics resulted at once from gamma irradiation. In several cases, a stabilizing effect appeared immediately and remained effective after long storage in various conditions (of temperature, or light, or oxygen exposure). This unexpected effect seems to be in accordance with previous experiments on gamma or electron irradiations of mixtures of organic molecules, reported in litterature: a mutual inhibition was observed to take place

  2. Studies on safety and efficiency of gamma-irradiated ginseng

    International Nuclear Information System (INIS)

    Gamma irradiation was applied to the biological quality improvement and preservation of white ginseng which has problems in a hygienic quality and storage stability. The current phosphine treatment showed no influence on microorganisms contaminated even though it was very useful for disinfestation of the sample, while 5 kGy irradiation effectively controlled the biological quality of the stored sample, with minimal effects on the quality parameters of white ginseng. Thus, it is concluded that gamma irradiation at a range of 5 kGy can be an alternative method of chemical fumigants provided air-tight packaging excluding recontamination is used for the stored product. (Author)

  3. The Financial Analysis of Gamma Irradiation Technology

    International Nuclear Information System (INIS)

    The present study discusses the guideline from the economics point of view of the commercial operation optimized for the Egyptian second irradiation facility. This study included four sections about the financial analysis, the analysis of future demand, future supply of commercial application of irradiation and the irradiation price system

  4. Neutron and gamma irradiation damage to organic materials.

    Energy Technology Data Exchange (ETDEWEB)

    White, Gregory Von, II; Bernstein, Robert

    2012-04-01

    This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

  5. Effect of {sup 60}Co radiation processing in mate (Ilex paraguariensis); Efeito do processamento por radiacao de {sup 60}Co na erva-mate (llex paraguariensis)

    Energy Technology Data Exchange (ETDEWEB)

    Furgeri, Camilo

    2009-07-01

    The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from {sup 60}Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative

  6. Preparation of FMD type A87/IRN inactivated vaccine by gamma irradiation and the immune response on guinea pig

    International Nuclear Information System (INIS)

    FMD is one of the most economically damaging diseases that affect livestock animals. In this study FMD Virus type A87/IRN was multiplied on BHK21 cells. The virus was titrated by TCID50 method, it was 107.5/ml. The FMD virus samples were inactivated by gamma ray from 60Co source at -20 deg C. Safety test was done by IBRS2 monolayer cell culture method, also antigenicity of irradiated and un-irradiated virus samples were studied by Complement Fixation Test. The dose/survival curve for irradiated FMD Virus was drawn, the optimum dose range for inactivation of FMDV type A87/IRN and unaltered antigenicity was obtained 40-44 kGy. The inactivated virus samples by irradiation and ethyleneimine (EI) were formulated respectively as vaccine with Al(OH)3 gel and other substances. The vaccines were inoculated to Guinea pigs and the results of Serum Neutralization Test for the normal vaccine and radio-vaccine showed protective titer after 8 months. The potency test of the inactivated vaccines was done, PD50 Value of the vaccines were calculated 7.06 and 5.6 for inactivated vaccine by EI and gamma irradiation respectively. (author)

  7. Effect of Different Polar Parts Extracted from Mucuna Birdwoodiana Tutcher on Peripheral Blood Counts of 60Coγray Irradiated Mice%白花油麻藤不同极性部位对60Coγ射线辐射小鼠外周血象的保护作用

    Institute of Scientific and Technical Information of China (English)

    王东晓; 陈若芸; 刘屏; 巩婷; 陈桂芸; 于腾飞; 马晓菲

    2008-01-01

    目的 观察白花油麻藤不同极性部位对骨髓抑制小鼠外周血象的影响,初步明确其促进造血的有效活性部位.方法 60 Coγ射线亚致死量辐射造成骨髓抑制小鼠模型,灌胃给予白花油麻藤各部位药液,于给药后1、3、7、14、21、28d检测其外周血白细胞(WBC)、红细胞(RBC)、血红蛋白(HGB)、血小板(PLT).结果 辐射后小鼠外周血WBC、RBC、HGB、PLT较正常组明显下降,给予白花油麻藤各部位治疗后,其下降趋势减缓,与模型组比较,白花油麻藤95%部分和水部分可显著促进辐射小鼠外周血WBC、RBC、HGB、PLT的恢复(P<0.05).结论 白花油麻藤50%乙醇提取物的95%洗脱部分和水洗脱部分可明显促进辐射所致骨髓抑制小鼠外周血象的恢复,可能是白花油麻藤促进造血的有效活性部位.

  8. Effects of heterogenous suberect spatholobus stem on peripheral blood cell counts of 60Co γ ray irradiated mice%同名异种鸡血藤对60Co γ射线辐射小鼠外周血象的影响

    Institute of Scientific and Technical Information of China (English)

    王虹; 刘屏; 戴畅; 王东晓

    2007-01-01

    目的:研究密花豆藤(Spatholobus suberectu)、白花油麻藤(Mucuna birdwoodiana)、皱果崖豆藤(Millettia oosperma)、香花崖豆藤(Millettia dielsiana)等4种同名异种鸡血藤对骨髓抑制小鼠外周血象的作用.方法:60Co γ射线亚致死量辐照造成骨髓抑制小鼠模型,灌胃给药,于给药后1、3、7、14和21 d监测其外周血白细胞、红细胞和血小板计数.结果:给予同名异种鸡血藤治疗后,小鼠外周血白细胞、红细胞和血小板计数下降趋势减缓,与对照组比较,白花油麻藤和密花豆藤高、低剂量组的白细胞、红细胞和血小板计数升高,差异有统计学意义(P<0.05).结论:同名异种鸡血藤均可在一定程度上促进辐射小鼠外周血象的恢复,其中密花豆藤和白花油麻藤作用相对较好.

  9. Inactivation of Lassa, Marburg, and Ebola viruses by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, L.H.; McCormick, J.B.; Johnson, K.M.

    1982-10-01

    Because of the cumbersome conditions experienced in a maximum containment laboratory, methods for inactivating highly pathogenic viruses were investigated. The infectivity of Lassa, Marburg, and Ebola viruses was inactivated without altering the immunological activity after radiation with /sup 60/CO gamma rays. At 4 degrees C, Lassa virus was the most difficult to inactivate with a rate of 5.3 X 10(-6) log 50% tissue culture infective dose per rad of /sup 60/CO radiation, as compared with 6.8 X 10(-6) log 50% tissue culture infective dose per rad for Ebola virus and 8.4 X 10(-6) log 50% tissue culture infective dose per rad for Marburg virus. Experimental inactivation curves, as well as curves giving the total radiation needed to inactivate a given concentration of any of the three viruses, are presented. The authors found this method of inactivation to be superior to UV light or beta-propiolactone inactivation and now routinely use it for preparation of material for protein-chemistry studies or for preparation of immunological reagents.

  10. Inactivation of Lassa, Marburg, and Ebola viruses by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, L.H.; McCormick, J.B.; Johnson, K.M.

    1982-10-01

    Because of the cumbersome conditions experienced in a maximum containment laboratory, methods for inactivating highly pathogenic viruses were investigated. The infectivity of Lassa, Marburg, and Ebola viruses was inactivated without altering the immunological activity after radiation with /sup 60/Co gamma rays. At 4 degrees C, Lassa virus was the most difficult to inactivate with a rate of 5.3 X 10(-6) log 50% tissue culture infective dose per rad of /sup 60/Co radiation, as compared with 6.8 X 10(-6) log 50% tissue culture infective dose per rad for Ebola virus and 8.4 X 10(-6) log 50% tissue culture infective dose per rad for Marburg virus. Experimental inactivation curves, as well as curves giving the total radiation needed to inactivate a given concentration of any of the three viruses, are presented. We found this method of inactivation to be superior to UV light or beta-propiolactone inactivation and now routinely use it for preparation of material for protein-chemistry studies or for preparation of immunological reagents.

  11. Effect of cobalt 60 gamma-ray irradiation on the hatching process of chicken eggs

    International Nuclear Information System (INIS)

    An experiment on fertilized chicken eggs was carried out to determine the effects of 60Co irradiation on the embryos, their fatality, and growth impairment or deformity, in particular. The experimental groups, consisting of 10 eggs each, recieved a 60Co irradiation of 50 to 2,000 rads on any one day between day 0 and day 20 of incubation. The larger the irradiation dose, the greater was the number of dead embryos. The fatality was higher in the groups receiving irradiation in the earlier stage (1st week). The resultant death was a chronic one. The irradiation also caused body weight decrease and growth impairment. A decrease in the brain and liver weights was noted, suggesting insufficiency in these organs. Deformity occurred in 4%, most of which involved impairments of skeletal growth, of the bones of the extremities and the bill, in particular. Administration of the SH amino acid, cysteine tended to alleviate the adverse effects of the 60Co irradiation. These results for fertilized chicken eggs suggest the possibility of abortion and the occurrence of deformities in human fetuses if they should be subjected to 60Co irradiation. (author)

  12. Ion exchange-based treatment of 60Co contaminated well-water for storing γ irradiation source%离子交换法处理60Co污染的γ辐照装置源井水

    Institute of Scientific and Technical Information of China (English)

    毕梦; 缪世林; 张晓露; 张友九

    2014-01-01

    Objective To select an efficient ion exchange resin to purify the 60Co contaminated well-water for storing radioactive source and to ensure the radioactivity of 60Co in treated well-water below 10 Bq/L.Methods The radioactivity of 60Co in the water samples was measured by using the potassium cobaltinitrite coprecipitation-β counting method.The treatment efficiencies of two different ion exchange resins for the simulated 60Co-bearing waste water were compared to select a better one to dispose of the 60Co contaminated well-water.Results The treatment efficiency of MBD-15-SC mixed ion exchange resin was about 5.8 times higher than ZGCNR50 strong-acid cation exchange resin.The radioactivity of 60Co in the contaminated well-water could be reduced from 4.16 × 105 Bq/L to 1.16 Bq/L by two-stage sorption of MBD-15-SC mixed ion exchange resin.Conclusions Using several times of two-stage MBD-15-SC mixed ion exchange resin could effectively purify the 60Co contaminated well-water.The quality of the treated well-water could meet the sewage discharge standards.%目的 选择合适的离子交换树脂处理60 Co污染的贮源井水,使污染的贮源井水中放射性水平低于10 Bq/L,满足排放要求.方法 通过亚硝酸钴钾共沉淀-β计数法测量水样中60Co的活度,比较两种不同离子交换树脂处理60Co污染模拟井水的效果,并选择净化效果较好的离子交换树脂处理60Co污染的源井水.结果 MBD-15-SC型混合离子交换树脂对模拟井水中60Co净化效果明显高于ZGCNR50型强酸性阳离子交换树脂,大约为5.8倍;采用多次两级MBD-15-SC型混合离子交换树脂循环处理污染的源井水,可使水中60Co放射性浓度从4.16×105 Bq/L降至1.16 Bq/L.结论 采用多次两级MBD-15-SC型混合离子交换树脂可有效处理60 Co污染的源井水,处理后的贮源井水符合排放要求.

  13. Tolerance, quality and storability of gamma-irradiated Egyptian rice

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on some organoleptic and physico-chemical properties and the storability of Egyptian rice was investigated. Radiation up to 50krad was chosen as an adequate dose causing non-significant changes in eating and cooking qualities. The effect of irradiation on degradation of starch and protein molecules is demonstrated on the basis of studies on the viscosity and solubility of rice paste. Irradiation at relatively low dose levels up to 50krad did not affect the chemical and nutritional qualities of rice regarding amino acids and B vitamins. It was also found that irradiation maintains better storability of rice under ambient temperature. (author)

  14. Assessing the mutagenic effects of gamma irradiation on Cajanus cajan (L. Huth and Vigna unguiculata (L. Walp landraces using morphological markers

    Directory of Open Access Journals (Sweden)

    Ogbuagu Udensi Ugorji

    2012-12-01

    Full Text Available Giving the high adaptability, heritability, genetic variability and nutritive values reported in the indigenous landraces of legumes, combined efforts should be geared towards their improvement.The present study aimed at evaluating the sensitivity of “Fiofio” Cajanus cajan (L. Huth and “Olaudi” Vigna unguiculata (L. Walp to gamma irradiation using morphological markers. Seeds of these legumes were exposed to gamma irradiation at 0, 200, 400, 600, 800 Gy from 60Co source. There was significant effect of gamma irradiation on days to 50% seedling emergence in a dosedependent fashion for “Fiofio” but it did not significantly affect the seedling emergence of “Olaudi”. Germination percentage was not affected concerning the two crops but the survival percentage was significantly reduced as the dose of exposure increased, especially for “Fiofio” variety. Growth and yield traits were increased in plants raised from seeds exposed to 200 Gy of gamma irradiation for both legumes. “Fiofio” plants raised from seeds treated with 400, 600 and 800 Gyhave died after two months, while those of “Olaudi” have presented a retarded growth. Explicitly, exposing the seeds of these legumes to 200 Gy of gamma irradiation could serve as a good springboard for theirimprovement.

  15. Kraft cooking of gamma irradiated wood, (2)

    International Nuclear Information System (INIS)

    Pre-irradiation of wood in alkaline aqueous ethanol increases kraft pulp yield by up to 1.2%, as already reported. In order to clarify the mechanism of the pulp yield gain, the behaviors of lignin and carbohydrates during pre-irradiation and cooking were investigated. The results are summarized as follows: 1) γ-Irradiation of guaiacylethane in alkaline aqueous ethanol produced 5-(1-hydroxyethyl)-guaicylethane, which is formed by radical coupling between α-hydroxyethyl radical from ethanol and guaiacylethane radical having an unpaired electron at C-5. 5,5'-Dehydrodiguaiacylethane, which may be a predominant product produced by γ-irradiation in the absence of ethanol, was also detected. 2) The yield of vanillin obtained by nitrobenzene oxidation of MWL decreased with an increase of γ-ray dosage. The presence of ethanol during γ-irradiation lessened the extent of this decrease and also the degradation of cellobiose. 3) Gel filtration of the products obtained by γ-irradiation of MWL and cellobiose in the presence of 14C-ethanol showed the possible combination between ethanol and MWL or cellobiose. 4) Molecular weight distributions of kraft lignin obtained from pre-irradiated beech chips were compared with those obtained from unirradiated chips. This result shows that γ-irradiation in the presence of ethanol decreases the ability of lignin to condense during kraft cooking. (author)

  16. Health protection and food preservation by gamma irradiation

    Science.gov (United States)

    1976-01-01

    Results of several major studies on food systems for space missions beginning with Apollo 12 through Apollo-Soyuz and investigations of the application of irradiation to food for manned space flight are reported. The study of flight food systems involved the application of radurization (pasteurizing levels) doses of gamma irradiation to flour and bread supplied by Pepperidge Farms in advance of the missions. All flights from Apollo 12 through 17 carried irradiated fresh bread. On Apollo 17, cooperation with Natick Laboratories permitted the introduction of a ham sandwich using irradiated bread and irradiated sterile ham. Investigations centered on irradiated bread were conducted during the course of these missions. Studies were applied to the concept of improving fresh bread from the point of view of mold inhibition. The studies considered how irradiation could best be applied at what levels and on a variety of bread types. Throughout the studies of the application of gamma irradiation the emphasis was placed upon using low levels of irradiation in the pasteurizing or radurizing doses--under a Megarad. The primary goal was to determine if a public health benefit could be demonstrated using radurization along with food preservation and food quality improvements. The public health benefit would be parallel to that of pasteurization of milk as a concept. Publications are included providing the details of these observations, one dealing with the flour characteristics and the other dealing with the influence on fresh bread types. These demonstrate the major findings noted during the period of the studies examining bread.

  17. Degradation of phorbol 12,13-diacetate in aqueous solution by gamma irradiation

    Science.gov (United States)

    Kongmany, Santi; Furuta, Masakazu; Matsuura, Hiroto; Okuda, Shuichi; Imamura, Kiyoshi; Maeda, Yasuaki

    2014-12-01

    Phorbol esters (PEs) are highly toxic compounds that cause skin irritation, inflammation, and tumor promotion upon contact with humans or animals. These compounds are naturally present in Jatropha curcas L. To promote the use of J. curcas seed oil in bio-diesel production industries and reduce environmental concerns, it is necessary to find methods of degrading PEs. In this study, the degradation of phorbol 12,13-diacetate (PDA), as a representative PE, in aqueous solution at a concentration of 10 mg/L by 60Co-γ-irradiation was investigated. The results demonstrate that PDA was effectively degraded by this treatment and the degradation efficiency increased with the absorbed dose within the range of 0.5-3 kGy. Complete degradation of PDA was achieved at a dose of 3 kGy. In the presence of radical scavengers (i.e., methanol, tert-butanol, 2-propanol), reactive species from water radiolysis were scavenged, and significant inhibition of PDA degradation was observed at absorbed doses less than 1 kGy. In the presence of nitrous oxide, the generation of hydroxyl radicals (rad OH) was promoted during gamma irradiation and PDA degradation was drastically enhanced.

  18. Effect of gamma irradiation on pre-treatment on the drying characteristics and qualities of wheat

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Yong; Wang, Jun [Zhejiang University (China). Dept. of Biosystems Engineering

    2008-07-01

    Wheat, pretreated by {sup 60}Co gamma irradiation, was dried by hot-air with irradiation dosage 0-3 kGy, drying temperature 40-60 deg C, and initial moisture contents 19-25% (drying basis). The drying characteristics and dried qualities of wheat were evaluated based on drying time, average dehydration rate, wet gluten content (WGC), moisture content of wet gluten (MCWG)and titratable acidity (TA). A quadratic rotation-orthogonal composite experimental design, with three variables (at five levels) and five response functions, and analysis method were employed to study the effect of three variables on the individual response functions. The five response functions (drying time, average dehydration rate, WGC, MCWG, TA) correlated with these variables by second order polynomials consisting of linear, quadratic and interaction terms. A high correlation coefficient indicated the suitability of the second order polynomial to predict these response functions. The linear, interaction and quadratic effects of three variables on the five response functions were all studied. (author)

  19. Effect of the phenolic antioxidants on the structure of gamma-irradiated model polyethylene

    Science.gov (United States)

    Andreucetti, N. A.; Sarmoria, C.; Curzio, O. A.; Valles, E. M.

    1998-06-01

    High energy radiation has been successfully employed to modify the chemical structure of commercial polymers. It induces at least two types of reaction in polyethylene: crosslinking and chain scission. In addition the efficiency of the radio-induced reactions can be affected by the presence of antioxidants. The purpose of this work is to study the effect of the irradiation on a model polyethylene containing a phenolic type antioxidant. Samples containing 0.1% and 1% by weight of Irganox 1010 (Ciba-Geigy) were irradiated under vacuum at room temperature with different doses of gamma rays from a 60Co source. Changes in structure and the average molecular weight were followed by gel permeation chromatography and low angle laser light scattering. The critical doses for gelation were determined as a function of the antioxidant concentration. Theoretical calculations to predict the evolution of molecular structure with extent of radiation were performed using a probability model. The agreement between the calculated and the measured molecular weights is very good.

  20. The influence of gamma irradiation on texture, color and viscosity properties of potato starch

    International Nuclear Information System (INIS)

    Food choices, while influenced by taste and nutritional value, have also symbolic enjoyment meanings. The texture, appearance, and flavor are important acceptability factors for any meal component. In our every day enjoyment of eating, texture is often as important as flavor. Starch is the most important source of carbohydrate in human nutrition and is widely used in many applications throughout the food industry. As an additive for food processing, food starches are typically used as thickeners and stabilizers in foods such as puddings, custards, soups, sauces, gravies, pie fillings, and salad dressings, and to make noodles and pastas. Potato starch is extracted from the root tubers of the potato plant. Radiation processing can be applied on foods for different purposes. It can also produce some modifications that are important to know. The aim of this research was to analyze the influence of gamma irradiation on texture, color and viscosity of potato starch. Starch samples were irradiated in a 60Co source Gammacell 220 with doses of 0, 5, 10 and 15 kGy. The results obtained showed that texture became inversely proportional to the applied radiation dose. Increasing doses promoted a slight rise in the parameter b* (yellow color) while the parameter L was not significantly affected. On the other hand, the viscosity of potato starch aqueous preparations decreased with the radiation dose, attributable to some degradation of starch molecules. (author)

  1. Evidence for successful acceptance of irradiated free gingival allografts in dogs. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rubenstein, H.S.; Ruben, M.P.; Levy, C.; Peiser, S.

    1975-04-01

    Free graft samples were excised and frozen to -55/sup 0/C. Subsequently the grafts were exposed to 2.5 x 10/sup 6/ rads of /sup 60/Co ..gamma..-radiation. The irradiated allogeneic grafts were later reconstituted and surgically transferred to four recipient subjects. Three autogenous nonirradiated grafts were also placed as controls. The animals were killed so as to furnish healing data at 0, 3, 7, 10, and 40 days postoperatively. Fourteen allografts were evaluated. They were judged to be nonantigenic, immunologically incompetent and nonviable. However, retention of an essentially unaltered connective tissue corium may have been instrumental in supporting subsequent epithelial regeneration from adjacent host tissue, while being passively incorporated into a very dynamic receptor zone. The graft thus served as a scaffolding for connective tissue deposition and attachment. It appears that the experimental regime obviated the immunologic interference usually encountered in allografting procedures. Thus, high intensity irradiation of the graft tissue may have rendered the tissue to be immunologically tolerable. Further studies are required to ascertain the duration of the host's immunologic unresponsiveness to the alien tissue, as well as ultimate structural and biologic fate of the transplanted tissues. Experiments are now in progress which have been designed to test the extent of immunologic sensitization induced by the grafted tissue.

  2. Shellfish depuration by gamma irradiation: Final report for the period October 1, 1985-September 30, 1986

    Energy Technology Data Exchange (ETDEWEB)

    Beghian, L.; Melnick, J.

    1986-11-01

    Irradiation of live bivalve molluscs is a promising new technique to reduce the public health threats of viral and bacterial pathogens in the consumption of raw shellfish. In studies conducted within the past year, live hardshelled clams and oysters were innoculated with Simian Rotavirus SA-11, Poliovirus I, and Hepatitis-A virus and treated with gamma ray ionizing radiation from University of Lowell/DOE 800,000 Curie /sup 60/Co source over a dose range of 0.5--10 kiloGray (50--1000 kilorad) to determine the effectiveness of the process in eliminating viral activity and thus easing the potential viral health threats associated with uncooked bivalves. Two viral strains, SA-11 and Poliovirus I, were employed as models to perfect laboratory technique and to estimate the most appropriate range of dose exposures necessary for optimal inactivation of the infectious pathogen, Hepatitis A. Post-irradiation survivorship of the oysters and quahogs was assessed over a range of exposures, and showed an exceptionally high degree of radioresistance for these molluscan species. 7 refs., 7 figs., 14 tabs.

  3. The influence of gamma irradiation on texture, color and viscosity properties of potato starch

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Bruna S.; Inamura, Patricia Y.; Mastro, Nelida L. del, E-mail: brunasaporito@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Food choices, while influenced by taste and nutritional value, have also symbolic enjoyment meanings. The texture, appearance, and flavor are important acceptability factors for any meal component. In our every day enjoyment of eating, texture is often as important as flavor. Starch is the most important source of carbohydrate in human nutrition and is widely used in many applications throughout the food industry. As an additive for food processing, food starches are typically used as thickeners and stabilizers in foods such as puddings, custards, soups, sauces, gravies, pie fillings, and salad dressings, and to make noodles and pastas. Potato starch is extracted from the root tubers of the potato plant. Radiation processing can be applied on foods for different purposes. It can also produce some modifications that are important to know. The aim of this research was to analyze the influence of gamma irradiation on texture, color and viscosity of potato starch. Starch samples were irradiated in a {sup 60}Co source Gammacell 220 with doses of 0, 5, 10 and 15 kGy. The results obtained showed that texture became inversely proportional to the applied radiation dose. Increasing doses promoted a slight rise in the parameter b* (yellow color) while the parameter L was not significantly affected. On the other hand, the viscosity of potato starch aqueous preparations decreased with the radiation dose, attributable to some degradation of starch molecules. (author)

  4. Gamma irradiation as a quarantine treatment for Neoleucinodes elegantalis in tomato fruit

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Helbert S.F.; Fanaro, Gustavo B.; Araujo, Michel M.; Santillo, Amanda G.; Villavicencio, Anna Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)], e-mail: villavic@ipen.br; Faria, Jose Tadeu de [Ministerio da Agricultura Pecuaria e Abastecimento (MAPA), Sao Paulo, SP (Brazil)], e-mail: dt-sp@agricultura.gov.br; Arthur, Valter [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). Lab. de Radibiologia e Ambiente], e-mail: arthur@cena.usp.br

    2009-07-01

    In Brazil the tomato-fruit-borer is responsible up to 45% for the loss of the production. The objective of the present report is evaluate the effects of gamma radiation ({sup 60}Co) on life cycle (eggs and larvae) of Neoleucinodes elegantalis in tomato fruits. The insects were irradiated at doses of 0 (control), 50, 100, 150, 200, 250, 300 and 400 Gy, in a Gammacell 220 source at dose rate of 1.4 kGy/h. Each treatment consists of four repetitions containing 10 insects, totaling 50 insects. After irradiation, the insects were maintained under controlled conditions of 25{+-}3 deg C and relative humidity from 65 to 75%. The evaluations were done daily, counted the number of died insects, eggs and emerged larvae. With the obtained results, we could determine the lethal and sterilizing doses for all phases of cycle life in N. elegantalis for a possible quarantine treatment to export tomato fruits. These results permit conclude that the dose capable to avoid further development of stage of eggs and larvae were doses of 100 and 200 Gy. (author)

  5. Investigation on the effects of gamma irradiation on bitumen

    Energy Technology Data Exchange (ETDEWEB)

    Mello, M.S.; Braz, D.; Motta, L.M.G., E-mail: Laura@coc.ufrj.br [Universidade Federal Rio de Janeiro (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Centro de Tecnologia; Leite, L.F.M., E-mail: leniml@petrobras.com.br [Centro de Pesquisa e Desenvolvimento Leopoldo Americo Miguez de Mello (CENPES/RJ), Rio de Janeiro (Brazil)

    2011-07-01

    Brazil has more than 218,000 km of asphalt-paved highways. Bitumen is a generic term for natural or manufactured black or dark-colored solid, semisolid, or viscous cementitious materials that are composed mainly of high molecular weight hydrocarbons (90-95%). Several papers have shown that the irradiation process has changed the mechanical behavior in some polymers. This work aims to analyze the behavior of Brazilian irradiated Bitumen (CAP 50-70). In order to provide a preliminary evaluation, bitumen samples and cylindrical specimens of asphaltic mixture were tested. The bitumen samples were irradiated 0.1 to 300 kGy, and asphaltic mixture specimen was irradiated 5 to 300 kGy. The cylindrical asphaltic mixture specimen of 10.16 cm diameter used in this study was molded using an asphalt-aggregate mixture. The specimens were irradiated in LIN/UFRJ/Brazil using a Gamma cell Co{sup 60} source of gamma irradiation with an applied dose rate of 29.7 Gy/min. After irradiated, the bitumen samples were subjected to penetration test and the asphaltic mixtures were subjected to indirect tensile strength test (diametral compression) for determination of the resilient modulus, according to ASTM method D 4123. The results of these experiments for each dose were compared with the control (nonirradiated). As expected, the penetration results showed that the ratio (irradiated/non-irradiated) decreases with increasing of irradiation dose for bitumen samples and the resilient modulus results showed that the ratio (irradiated/non-irradiated) increases with increasing of irradiation dose for asphaltic mixture. (author)

  6. The pros and cons of polyethylene sterilization with gamma irradiation.

    Science.gov (United States)

    Hopper, Robert H; Engh, C Anderson; Fowlkes, LaTonya B; Engh, Charles A

    2004-12-01

    This retrospective study evaluated the implant, patient and surgical factors associated with polyethylene wear for one type of porous-coated hemispheric total hip arthroplasty cup. Radiographic wear measurements among 567 Duraloc cups (512 patients) revealed that liners sterilized by gamma-irradiation wore 0.085 mm/year less than those that were sterilized by gas-plasma, a noncross-linking chemical surface treatment. The substantially decreased wear rate associated with gamma-irradiation was attributed to sterilization-induced polyethylene cross-linking. Shelf-aging adversely affected liners that were gamma irradiated in air. On average, highly crystalline Hylamer liners showed a 0.064 mm/year increase in wear rates for each year of shelf storage after terminal sterilization with gamma-irradiation in air. Among conventional Enduron liners, the effect of shelf aging after gamma-irradiation in air was more modest, increasing wear rates by 0.014 mm/year for each year of shelf storage. Because Hylamer's wear performance degraded at about five times the rate of Enduron's, the improved wear resistance associated with gamma-irradiation in air would be lost after 1.3 years of shelf aging for Hylamer compared with 6.1 years for Enduron. For every additional year of age at the time of surgery, the wear rate decreased by 0.003 mm/year. Increased body mass index, a preoperative diagnosis of inflammatory arthritis, and a ceramic femoral head also were associated with decreased wear rates. PMID:15577466

  7. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS (REVISION 1)

    Energy Technology Data Exchange (ETDEWEB)

    Clark, E.

    2013-09-13

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Revision 1 adds a comparison with results of a study of tritium exposed EPDM. The amount of gas produced by the gamma irradiation was found to be equivalent to about 280 days exposure to initially pure tritium gas at one atmosphere. The glass transition temperature of the tritium exposed EPDM rose about 10 �C. over 280 days, while no glass transition temperature change was observed for gamma irradiated EPDM. This means that gamma irradiation in deuterium cannot be used as a surrogate for tritium exposure.

  8. Technical Safety Requirements for the Gamma Irradiation Facility (GIF)

    CERN Document Server

    Mahn, J A E M J G

    2003-01-01

    This document provides the Technical Safety Requirements (TSR) for the Sandia National Laboratories Gamma Irradiation Facility (GIF). The TSR is a compilation of requirements that define the conditions, the safe boundaries, and the administrative controls necessary to ensure the safe operation of a nuclear facility and to reduce the potential risk to the public and facility workers from uncontrolled releases of radioactive or other hazardous materials. These requirements constitute an agreement between DOE and Sandia National Laboratories management regarding the safe operation of the Gamma Irradiation Facility.

  9. Effects of aeration on gamma irradiation of sewage sludge

    Science.gov (United States)

    Chu, Libing; Wang, Jianlong; Wang, Bo

    2010-08-01

    In this paper the effect of aeration on gamma irradiation of sewage sludge was investigated to examine the potential solubilization of solids in sewage sludge to ultimately reduce the solids volume for disposal. Results showed that aeration increased the effectiveness of gamma radiation. The efficiency of sludge solubilization with aeration was increased by around 25% compared to that without aeration at an irradiation dose of 2.5-9 kGy. The soluble protein, polysaccharide and humic (like) substance concentrations were higher under aerated conditions. With aeration the overall reaction appears to be oxidative as evidenced by the higher nitrate and nitrite ion concentrations in solution.

  10. Effects of low-dose. gamma. -irradiation on grapefruit products

    Energy Technology Data Exchange (ETDEWEB)

    Moshonas, M.G.; Shaw, P.E.

    Products obtained from Florida grapefruit irradiated with low-dosage ..gamma..-rays as a possible treatment for infestation by larvae of the Caribbean fruit fly were evaluated to determine effects on flavor and composition. Seven tests were run in which twenty-two lots of fruit were exposed to 7.5, 15, 30, 60 or 90 krd of ..gamma..-irradiation covering the 1981-1982 and early 1982-1983 harvesting season. There were few significant adverse flavor effects on products from irradiated fruit with the exception of the first test run on early-season fruit. In some cases, particularly at the lower doses of radiation, there was a significant improvement of flavor in grapefruit sections. There were no marked differences in vitamin C, sugar or acid levels in juice nor on essential peel oil composition of volatile constituents from irradiated fruit when compared with those from untreated fruit. 18 references, 2 tables.

  11. Gamma irradiation induced variation in carrots (Daucus Carota L.)

    International Nuclear Information System (INIS)

    Carrot tissue cultures, germinating seed, and dry seed were exposed to gamma radiation. Irradiation accelerated germination of carrot seed in the M1 generation at low doses (0.5 and 1 krad), whereas higher doses delayed germination. A high negative correlation was observed between dose and survival of plants after seed irradiation. Plant size and root weight were 20% to 35% greater than control plants after seeds, but not tissue culture, were exposed to low doses of gamma irradiation. Higher doses reduced M1 plant size by > 50% in germinating seed and tissue culture treatments but less for the dry seed treatment. Seed production decreased while phenotypic variation of M1 plants increased with increasing gamma ray dosage. Root weight and total dissolved solids were highly variable in M2 families. Less variation was observed in total carotene content and none was seen in sugar type [reducing vs. non reducing sugars]. Induced variation in root color and rot shape was also observed. Irradiation of germinating seed and tissue cultures yielded more M2 variation than irradiation of dry seed. Putative point mutations were not observed. Unirradiated carrot tissue cultures did not yield significant M2 somaclonal variation. Average root weight of M2 plants increased with increasing gamma ray dosage, especially for the dry seed treatment (Author)

  12. Gamma irradiation-induced variation in carrots (Daucus carota L.)

    International Nuclear Information System (INIS)

    Carrot tissue cultures, germinating seed, and dry seed were exposed to gamma radiation. Irradiation accelerated germination of carrot seed in the M1 generation at low doses (0.5 and 1 krad), whereas higher doses delayed germination. A high negative correlation was observed between dose and survival of plants after seed irradiation. Plant size and root weight were 20% to 35% greater than control plants after seeds, but not tissue cultures, were exposed to low doses of gamma irradiation. Higher doses reduced M1 plant size by 50% in germinating seed and tissue culture treatments but less for the dry seed treatment. Seed production decreased while phenotypic variation of M1 plants increased with increasing gamma ray dosage. Root weight and total dissolved solids were highly variable in M2 families. Less variation was observed in total carotene content and none was seen in sugar type (reducing vs. non reducing sugars). Induced variation in root color and root shape was also observed. Irradiation of germinating seed and tissue cultures yielded more M2 variation than irradiation of dry seed. Putative point mutations were not observed. Unirradiated carrot tissue cultures did not yield significant M2 somaclonal variation. Average root weight of M2 plants increased with increasing gamma ray dosage, especially for the dry seed treatment

  13. Sorption of 60 Co on inorganic solids

    International Nuclear Information System (INIS)

    The behavior of sorption of the 60 Co in aqueous solution under static conditions to different values of pH of the aqueous solution (1, 3, 5, 7, and 10) on MgO, MnO2, SnO, TiO2, activated carbon and calcinate hydrotalcite was investigated. It was found that the best sorbents of the 60 Co was the MnO2, activated carbon and TiO2 whose sorption was incremented when increasing the pH value of the aqueous solutions, in the one case of the hydrated oxides, the 60 Co interacted with the electrically charged surface of the sorbents that depends on the pH of the solution and of the point of zero charge (zpc) of the sorbent. (Author)

  14. Response-surface models for deterministic effects of localized irradiation of the skin by discrete {beta}/{gamma} -emitting sources

    Energy Technology Data Exchange (ETDEWEB)

    Scott, B.R.

    1995-12-01

    Individuals who work at nuclear reactor facilities can be at risk for deterministic effects in the skin from exposure to discrete {Beta}- and {gamma}-emitting ({Beta}{gamma}E) sources (e.g., {Beta}{gamma}E hot particles) on the skin or clothing. Deterministic effects are non-cancer effects that have a threshold and increase in severity as dose increases (e.g., ulcer in skin). Hot {Beta}{gamma}E particles are {sup 60}Co- or nuclear fuel-derived particles with diameters > 10 {mu}m and < 3 mm and contain at least 3.7 kBq (0.1 {mu}Ci) of radioactivity. For such {Beta}{gamma}E sources on the skin, it is the beta component of the dose that is most important. To develop exposure limitation systems that adequately control exposure of workers to discrete {Beta}{gamma}E sources, models are needed for systems that adequately control exposure of workers to discrete {Beta}{gamma}E sources, models are needed for evaluating the risk of deterministic effects of localized {Beta} irradiation of the skin. The purpose of this study was to develop dose-rate and irradiated-area dependent, response-surface models for evaluating risks of significant deterministic effects of localized irradiation of the skin by discrete {Beta}{gamma}E sources and to use modeling results to recommend approaches to limiting occupational exposure to such sources. The significance of the research results as follows: (1) response-surface models are now available for evaluating the risk of specific deterministic effects of localized irradiation of the skin; (2) modeling results have been used to recommend approaches to limiting occupational exposure of workers to {Beta} radiation from {Beta}{gamma}E sources on the skin or on clothing; and (3) the generic irradiated-volume, weighting-factor approach to limiting exposure can be applied to other organs including the eye, the ear, and organs of the respiratory or gastrointestinal tract and can be used for both deterministic and stochastic effects.

  15. Apoptosis and necrosis in testes irradiated with gamma rays

    International Nuclear Information System (INIS)

    The present study focused on sub-microscopical investigation of apoptotic and necrotic cells in the testes of dogs subjected to single local irradiation with gamma rays at three different doses, 1.5 Gy, 3 Gy and 4 Gy, on days 1, 15, 30, 45, 120 and 150 after irradiation. On day 1 after irradiation, no necrotic cells were observed in the testicular tissue. The first cells in which apoptosis was observed on days 15 and 30 after irradiation with the lower dose were spermatogonia, spermatocytes and round spermatids. These cells showed morphological changes typical of apoptosis. Their depletion was observed on day 45 after irradiation and they were found in the lumen of seminiferous tubuli. Some dead cells were eliminated from seminiferous tubuli by phagocytosis by means of Sertoli cells. After irradiation with higher doses of gamma rays some cells of seminiferous epithelium showed morphological signs of apoptosis while other manifested necrosis. Sertoli cells and Leydig cells were considerably resistant to radiation. However, after irradiation with the highest dose of 4 Gy sporadic cells showed signs of apoptosis. On day 120 after irradiation the testes contained no necrotic cells and by day 150 spermiogenesis was recovered. (authors)

  16. Biosolubilization gamma irradiate ion result coal by mould trichoderma sp

    International Nuclear Information System (INIS)

    Biosolubilization of coal is process of converting solid coal to liquid fuel/chemicals by mean of microorganism. The aim of this research was to study the effect of gamma rays irradiation with varian doses of irradiation into solubilization of subbituminous coal by Trichoderma sp. The dosage used was 5, 10, and 20 kGy and unirradiated coal as control. The method was submerged culture in MSS+ medium and incubated at room temperature and agitated at 150 rpm for 21th days. The parameters observed were colonization, pH and biosolubilization product based on absorbance value at λ250nm and λ450nm and GC/MS analysis for the best treatment. The results showed that coal biosolubilization could be increased by gamma irradiation. The mould could growth well in medium containing irradiated coal and the medium of pH was decreased after incubation. The biosolubilization was increased but the irradiation dosage of coal didn't affect significantly. The best dose was 20 kGy with product biosolubilization similar to gasoline and solar. Based on the result, the pre-treatment of gamma irradiation on coal has potency to increased biosolubilization. (author)

  17. Obtainment of a drug delivery system from PVAL irradiated by gamma rays

    International Nuclear Information System (INIS)

    The poly(vinyl alcohol) (PVAL) is a polymer used as biomaterial. In this work the PVAL was irradiated by gamma rays from 60Co source with doses up to 200 kGy. The PVAL was used to prepare hydrogels that may be used as a drug delivery system in ocular implant, for pair PVAL/dihidroxypropoximethyl guanine, where the last one is used for treatment of people with retinite caused by cytomegalovirus. The dose effect was studied on various properties of PVAL: the molecular weight by viscosity, the crosslink degree (Gcross-link= 8,5) calculated from gel dose (Dg = 7,8 kGy), the average molecular weight between crosslinks, crosslinking density, tensile strength at break and the degree of crystallinity by differential scanning calorimetry. Formation and thermal decay radical were studied by electronic paramagnetic resonance. It was used the technique of superposition and subtraction of spectra obtained at various temperatures (77 K, 125 K, 170 K, 230 K and 280 K). The radicals formed were identified on irradiated PVAL on vacuum and air at 77K with 20 kGy. The thermal decay showed that air caused polymer oxidation, even after end the irradiation, because the ·OH, RO· and ROO · radicals were formed. The dose effect on molecular structure of PVAL was studied by transmission spectroscopy on infrared region and nuclear magnetic resonance of proton. The PVAL structural alteration was not observed up to 200kGy, although crosslink occurred on PVAL. The PVAL hydrogel formation occurred at doses upper 70 kGy and drug controlled released occurred with zero order kinetic on PVAL hydrogel irradiated with 80 kGy. (author)

  18. Influence of gamma irradiation effects on the residual alteration rate of the French SON68 nuclear glass

    Energy Technology Data Exchange (ETDEWEB)

    Rolland, S. [CEA/DEN/DTCD/SECM, BP 17171, 30207 Bagnols sur Cèze cedex (France); Tribet, M., E-mail: magaly.tribet@cea.fr [CEA/DEN/DTCD/SECM, BP 17171, 30207 Bagnols sur Cèze cedex (France); Jollivet, P.; Jégou, C.; Broudic, V.; Marques, C. [CEA/DEN/DTCD/SECM, BP 17171, 30207 Bagnols sur Cèze cedex (France); Ooms, H. [Instrumentation Department SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol (Belgium); Toulhoat, P. [Université de Lyon 1, CNRS/ISA, UFR de Chimie Biochimie, 69622 Villeurbanne cedex (France); INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil en Halatte (France)

    2013-02-15

    The residual rate regime of SON68 nuclear glass has been investigated here by static experiments under external irradiation. The experiments were carried out in a gamma irradiator with {sup 60}Co sources. Four dose rates were studied: two high dose rates (5 and 10 kGy h{sup −1}) to exacerbate electronic radiation effects, and two lower dose rates (0.8 and 0.05 kGy h{sup −1}). The objective of this work is not to assess potential LET effects but to assess more widely electronic effects on the residual rate regime which controls the long term stability of the glass under geological disposal. Fresh glasses were leached in argon atmosphere at 90 °C and at a high surface-area-to-volume ratio (SA/V = 10 000 m{sup −1}). Under these conditions the system quickly reaches the residual alteration rate regime. The alteration rate was monitored by solution analyses: the release of glass alteration tracer elements—in particular boron, sodium and lithium—was measured by ICP-AES. The hydrogen peroxide produced by water radiolysis was quantified by chemiluminescence. Radiation effects on the glass and its gel network were characterized by scanning electron microscopy (SEM) and Transmission Electron Microscopy (TEM). Higher H{sub 2}O{sub 2} concentrations were measured on irradiated samples in the presence of glass, suggesting an irradiation effect on the glass and its alteration layer. However, the data obtained on glass alteration show that potential defects or changes induced by gamma irradiation do not modify the kinetics of alteration up to a gamma dose rate of 10 kGy h{sup −1}: the residual rates measured for the different dose rates studied are similar and comparable to experiments performed without irradiation. Moreover, these observations are consistent with SEM and TEM characterizations which show that the alteration layer formed under gamma irradiation is similar to the alteration layer formed without irradiation. This study demonstrates that species produced

  19. Dose rate effect in food irradiation

    International Nuclear Information System (INIS)

    It has been suggested that the minor losses of nutrients associated with radiation processing may be further reduced by irradiating foods at the high dose rates generally associated with electron beams from accelerators, rather than at the low dose rates typical of gamma irradiation (e.g. 60Co). This review briefly examines available comparative data on gamma and electron irradiation of foods to evaluate these suggestions. (137 refs., 27 tabs., 11 figs.)

  20. Microbiological and chemical characteristics of gamma irradiated roasted Veal Meat

    International Nuclear Information System (INIS)

    This investigation aims 10 study the possibility of using gamma irradiation at doses of 1,3 and 5 KGy for microbial decontamination of roasted veal meat (kebab). The samples were purchased from local market and examined for the counts of Staphylococcus aureus, Bacillus cereus, presence of Salmonella spp and the counts of total bacterial, molds and yeasts and Enterobacteriaceae. The results illustrated that all samples were positive for Staphylococcus aureus, Bacillus cereus, while Salmonella spp was detected in only 3 samples. Therefore, these product samples were gamma irradiated at doses of 0,1,3 and 5 kGy, then stored at cold storage (4±1 degree C). The effects of these treatments on the microbiological, chemical and sensory characteristics were studied post treatment and during cold storage. Irradiation at 1 kGy reduced the counts of total bacterial, molds and yeasts, Enterobacteriaceae, Staphylococcus aureus and Bacillus cereus as well as eliminating Salmonella spp. On the other hand, irradiation at 3 and 5 kGy doses completely eliminated the present Enterobacteriaceae, S. aureus, B, cereus and Salmonella spp. Irradiation of samples increased their amounts of thiobarbituric acid reactive substances (TBARS) but it did not affect the sensory characteristics of samples and it had no effects on their total volatile nitrogen (TVN) contents, while storage increased the TBARS and TVN for irradiated and non-irradiated samples. Gamma irradiation treatments had no effects on the sensory characteristics for appearance, odor and taste of all kebab samples and extended their time of sensory preference. However, doses of 1, 3 and 5 kGy reduced the counts of total bacteria and extended of the refrigerated shelf-life of samples to 11, 23 and 29 days, respectively, compared to 5 days for non-irradiated controls

  1. A standard Fricke dosimeter compared to an ionization chamber used for dosimetric characterization of 60Co photon beam

    Science.gov (United States)

    Moussous, Ouiza; Medjadj, Toufik

    2016-06-01

    The main objective of this study was to investigate the Fricke dosimeter water equivalent system for measurement of dosimetric parameters for photon beam. The parameters measured with the Fricke dosimeter were compared to those obtained with an ionization chamber. In this work characteristics for 60Co γ-rays of field sizes ranging from 5 × 5 cm2 to 20 × 20 cm2 are reported. The measurements were carried out in the secondary standard dosimetry laboratory using a collimated 60Co gamma source therapy unit. The 60Co beam output in terms of absorbed dose to water was obtained as per IAEA TRS 398 recommendations using cylindrical ionization chamber, whose ND,w has been supplied by the IAEA's reference laboratory. Specific quantities measured include: output factors, peak scatter factor, lateral beam profiles and percentage depth dose. The Fricke dosimeters were irradiated in a water phantom using the suitable poly (methyl methacrylate), PMMA stand. Our results demonstrate that Fricke dosimeter and ionization chamber agree with each other.

  2. Effects of presowing gamma irradiation on the photosynthetic pigments, sugar content and carbon gain of Cullen corylifolium (L. Medik.

    Directory of Open Access Journals (Sweden)

    Sumira Jan

    2013-12-01

    Full Text Available To determine the effects of gamma radiation on the photosynthetic pigments, sugar content and total carbon gain, seeds of Cullen corylifolium (L. Medik. were irradiated with variable doses (0, 2.5, 5, 10, 15, and 20 kGy at the rate of 1.65 kGy h-1 from 60Co gamma source. Cullen corylifolium represents an important Chinese medicine with adequate levels of secondary metabolites, thus we hypothesized that gamma irradiation could modulate primary metabolites which could supplement secondary metabolite levels. The seeds were then transferred to field for biochemical analysis at different developmental stages; pre-flowering, flowering and post-flowering. Gamma dosage at 10 kGy resulted in a significant increase in concentration of chlorophyll a (61.17%, chlorophyll b (93.18% and total chlorophyll (71.66%, suggesting that low doses of radiation could activate photosynthetic pigment system while at 15 and 20 kGy dose resulted in depletion of such parameters. Sugar and total C analysis of plants irradiated at 10 kGy demonstrated significantly maximum (216.01% sugar content in leaves at all developmental stages and significantly minimum (46.13% and (57.81% in plants raised from seeds irradiated at 15 and 20 kGy respectively. Effective stimulatory dose for C. corylifolium '11062' is 10 kGy. In contrast, the carotenoid content of the plants exposed to 15 and 20 kGy was maximum than control. Significance of such stimulation correlated with increasing C mass of the plant concerned is discussed in the light of newer aspects in research.

  3. Influence of low-dose gamma-ray irradiation on mitosis and adaptive response of meristematic cells of pea rootlets

    International Nuclear Information System (INIS)

    Pea seeds (Pisum sativa) were exposed to gamma irradiation (60Co, dose 7 Gy) at different dose rates (from 0.3 cGy/h to 19.1 cGy/h). The beginning of irradiation coincided with the beginning of soaking. After the irradiation a fraction of the seeds was irradiated with 50 Gy (137Cs, dose rate 25 Gy/min) to examine the adaptive response. After 24 hours of soaking all the seeds were germinated at 25 deg C and rootlets were fixed. Mitotic index and the number of cells with chromosomal aberrations (CA) in first mitosis anaphases of the meristematic cells of rootlets were determined. After 7 cGy irradiation, judging by the above criteria, the radiation hormesis was identified at the dose rate 1.2 cGy/h. For 19.1 cGy/h damaging effect and decrease in the mitotic activity were observed. As the dose rate grows, the adaptive response is better expressed (by the analysis of CA). When the seeds are conserved at 13-14 % humidity, the CA level is higher and the adaptive response is better expressed compared to conserving at 10 % humidity. (author)

  4. Conservation of garlic bulbs (Allium sativum L. ) by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.; Arranz, T.

    1979-01-01

    The effect of different doses of gamma radiation (from 5 to 30 krad) on the conservation of garlic bulbs during a 12 months period is studied. Irradiations were made at three different times and the best results were obtained with the treatment given during the two months following harvest. During this period, 5 krad are enough to inhibit garlic bulbs sprouting.

  5. Gamma irradiation for food preservation and sterilization of medical supplies

    International Nuclear Information System (INIS)

    A new technology in food preservation by using gamma irradiation was introduced and its advantages over a number of conventional processes were discussed. The new technique is also applicable in the sterilization of medical supplies. It is relatively simple and does not require very highly skilled manpower

  6. Dosimetry computer module of the gamma irradiator of ININ

    International Nuclear Information System (INIS)

    This work present the technical specifications for the upgrade of the dosimetry module of the computer system of the gamma irradiator of the Instituto Nacional de Investigaciones Nucleares (ININ) whose result allows the integration and consultation of information in industrial dosimetry subject under an outline client-server. (Author)

  7. Conservation of garlic bulbs (allium sativum L.) by gamma irradiation

    International Nuclear Information System (INIS)

    The effect of different doses of gamma radiation (from 5 to 30 krad) on the conservation of garlic bulbs during a 12 months period is studied. Irradiations were made at three different times and the best results were obtained with the treatment given during the two months following harvest. During this period, 5krad are enough to inhibit garlic bulbs sprouting. (author)

  8. Thermoluminescence response of gamma-irradiated sesame with mineral dust

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez L, Y. [CSIC, Instituto de Estructura de la Materia, Calle Serrano 121, 28006 Madrid (Spain); Correcher, V. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Garcia G, J. [CSIC, Museo Nacional de Ciencias Naturales, Calle Jose Gutierrez Abascal 2, 28006 Madrid (Spain); Cruz Z, E., E-mail: y.r.l@csic.es [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior s/n, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2011-10-15

    The thermoluminescence (Tl) emission of minerals isolated from Mexican and Indian sesame seeds appear as a good tool to discern between irradiated and non-irradiated samples. According to the X-ray diffraction and environmental scanning microscope, the adhered dust in both samples is mainly composed by different amounts of quartz and feldspars. These mineral phases exhibit (i) enough sensitivity to ionizing radiation inducing good Tl intensity, (ii) high stability of the Tl signal during the storage of the material (i.e. low fading) and (iii) are thermally and chemically stable. Blind tests performed under laboratory conditions, but simulating industrial preservation processes (similar temperature and moisture, and presence of white light), allows to distinguish between 1 KGy gamma-irradiated and non-irradiated samples even 11000 hours (15 months) after the irradiation proceeding. (Author)

  9. Gamma irradiation effects on dexamethasone and triamcinolone acetonide

    International Nuclear Information System (INIS)

    The effects of cobalt-60 gamma rays on dexamethasone and triamcinolone acetonide were examined by physico-chemical determination. Irradiation dose used were 0, 20 and 49 kGy while storage time were 0 and 6 months at about 30 ± 2oC. The results showed that irradiation up to a dose of 40 kGy and 6 months storage time do not give any change on the UV spectra, DSC thermograms, and infrared spectra of the powder and also do not give any significant effect on acid value, pH and viscosity of the eye ointments (p<0.05). There were significant changes in iodine value after irradiation and storage treatment. The HPLC chromatograms of triamcinolone acetonide powder and eye ointment showed that some degradation caused by irradiation have taken place but there was no change on the HPLC chromatogram of dexamethasone after irradiation. (author). 24 refs

  10. Survival patterns and hemopathological responses of dogs under continuous gamma irradiation

    International Nuclear Information System (INIS)

    Survival curves were constructed and analyzed relative to contributing hematopathological responses for groups of beagles exposed continuously for duration of life to low daily doses of whole body 60Co gamma irradiation (27.3 rads/day to 4 rads/day). The survival curves versus time were progressively displaced toward longer survival as rates of exposure were reduced from the relatively high dose rate of 27.3 rads/day to the low dose rate of 4.0 rads/day. Average survival times increased from 57 days at 27.3 rads/day to 1830 days at 4.0 rads/day, representing fractional increased life-spans from 1.5% to 50.8%, respectively. Survival curves versus total dose were markedly displaced along the cumulative radiation dose axis at the extreme dose rates (i.e., 27.3 and 4.0 rads/day), but not at the intermediate dose rates (i.e., 13.4 and 7.9 rads/day) in which the upper linear portions of the survival curves are superimposed. From these dose-dependent survival curves, LD50 values for whole body gamma irradiation, delivered chronically at 27.3, 13.4, 7.9, and 4.0 rads per day were estimated to be 1442, 2124, 2039, and 7161 rads, respectively. Both time- and dose-dependent survival curves for the intermediate dose rates, in contrast to the extreme dose rates, exhibited pronounced transitions in the lethality rate below the 50% survival level. These lethality rate transitions occurred at approx. 2500 rads of accumulated dose and were attributed to a shift in the spectrum of developing hematopathologies: namely, from a predominance of the acutely ablative radiation-induced lymphohematopoietic syndromes (i.e., septicemias and aplastic anemias) to a predominance of the late arising hematopoietic neoplasias (myelogenous leukemia and related myeloproliferative disorders)

  11. In vitro response of the human breast cancer cell line MDAMB-231 and human peripheral blood mononuclear cells exposed to {sup 60}Co at single fraction

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Lidia Maria; Campos, Tarcisio Passos Ribeiro de [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear]. E-mail: lidia.andrade@unifenas.br; Leite, M.F. [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Fisiologia e Biofisica; Goes, A.M. [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Bioquimica e Imunologia

    2005-10-15

    Radiotherapy using gamma rays is a common modality of breast cancer treatment. The aim of this research is to investigate the biological response of the human breast cancer cell line MDAMB-231 and human peripheral blood mononuclear cells (PBMC) exposed in vitro to {sup 60} Co irradiation at a single fraction of 10 Gy, 25 Gy and 50 Gy doses at 136,4 cGy.min{sup -1} rate. Cells were irradiated at room temperature by the Theratron 80 radiotherapy system. Biological response was evaluated through cellular viability using MTT assay and nucleus damages visualized by Propidium Iodide assay and electrophoresis agarose gel after gamma irradiation. Nucleus damages induced by {sup 60} Co irradiation were compared to damage caused by cell exposure to 10% methanol. The 50 Gy dose of irradiation did not stimulate nucleus damages at the same level as that affected by 10% methanol induction in the MDAMB-231. Further studies are necessary to understand these mechanisms in the MDAMB-231 human breast carcinoma cell line.(author)

  12. Stability of Grafted Polymer Nanoscale Films toward Gamma Irradiation.

    Science.gov (United States)

    Borodinov, Nikolay; Giammarco, James; Patel, Neil; Agarwal, Anuradha; O'Donnell, Katie R; Kucera, Courtney J; Jacobsohn, Luiz G; Luzinov, Igor

    2015-09-01

    The present article focuses on the influence of gamma irradiation on nanoscale polymer grafted films and explores avenues for improvements in their stability toward the ionizing radiation. In terms of applications, we concentrate on enrichment polymer layers (EPLs), which are polymer thin films employed in sensor devices for the detection of chemical and biological substances. Specifically, we have studied the influence of gamma irradiation on nanoscale poly(glycidyl methacrylate) (PGMA) grafted EPL films. First, it was determined that a significant level of cross-linking was caused by irradiation in pure PGMA films. The cross-linking is accompanied by the formation of conjugated ester, carbon double bonds, hydroxyl groups, ketone carbonyls, and the elimination of epoxy groups as determined by FTIR. Polystyrene, 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl, dimethylphenylsilanol, BaF2, and gold nanoparticles were incorporated into the films and were found to mitigate different aspects of the radiation damage. PMID:26259102

  13. Effect of gamma irradiation on physicochemical properties of commercial poly(lactic acid) clamshell for food packaging

    Science.gov (United States)

    Madera-Santana, Tomás J.; Meléndrez, R.; González-García, Gerardo; Quintana-Owen, Patricia; Pillai, Suresh D.

    2016-06-01

    Poly(lactic acid) (PLA) is a well-known biodegradable polymer with strong potential application in food packaging industry. In this paper, samples of PLA clamshell for tomatoes packaging were exposed with 60CO γ-ray's source (1.33 MeV) at different dose levels (0, 10, 60, 150, 300, and 600 kGy), at room temperature and in presence of air. The physicochemical properties of neat PLA and sample exposed to gamma irradiation were investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and tensile measurements. Results show as the dose increases, the molecular weight (Mw), melting t