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Sample records for post-irradiation protective effect

  1. Post irradiation effects (PIE) in integrated circuits

    International Nuclear Information System (INIS)

    Barnes, C.E.; Shaw, D.C.; Fleetwood, D.M.; Winokur, P.S.

    1992-01-01

    Post Irradiation Effects (PIE) ranging from normal recovery catastrophic failure have been observed in integrated circuits during the PIE period. These variations indicate that a rebound or PIE recipe used for radiation hardness assurance must be chosen with care. In this paper, the authors provide examples of PIE in a variety of integrated circuits of importance to spacecraft electronics

  2. Modeling of MOS radiation and post irradiation effects

    International Nuclear Information System (INIS)

    Neamen, D.A.

    1984-01-01

    The radiation response and long term recovery effects in a n-channel MOSFET due to a pulse of ionizing radiation were modeled assuming that electron tunneling from the semiconductor into the oxide and the buildup of interface states were the postirradiation recovery mechanisms. The modeling used convolution theory and took into account the effects of bias changes during the recovery period and charge yield effects. Changing the bias condition during the post-irradiation recovery period changed the recovery rate. The charge yield effects changed the density of trapped positive charge in the oxide but did not change the recovery characteristics for a given oxide thickness. The modeling results were compared to previous experimental results

  3. Post-irradiation inactivation, protection, and repair of the sulfhydryl enzyme malate synthase

    International Nuclear Information System (INIS)

    Durchschlag, H.; Zipper, P.

    1985-01-01

    Malate synthase from baker's yeast, a trimeric sulfhydryl enzyme with one essential sulfhydryl group per subunit, was inactivated by 2 kGy X-irradiation in air-saturated aqueous solution (enzyme concentration: 0.5 mg/ml). The radiation induced changes of enzymic activity were registered at about 0,30,60 h after irradiation. To elucidate the role of OH - , O 2 , and H 2 O 2 in the X-ray inactivation of the enzyme, experiments were performed in the absence of presence of different concentrations of specific additives (formate, superoxide dismutase, catalase). These additives were added to malate synthase solutions before or after X-irradiation. Moreover, repairs of inactivated malate synthase were initiated at about 0 or 30 h after irradiation by means of the sulfhydryl agent dithiothreitol. Experiments yielded the following results: 1. Irradiation of malate synthase in the absence of additives inactivated the enzyme immediately to a residual activity Asub(r)=3% (corresponding to a D 37 =0.6 kGy), and led to further slow inactivation in the post-irradiation phase. Repairs, initiated at different times after irradiation, restored enzymic activity considerably. The repair initiated at t=0 led to Asub(r)=21%; repairs started later on resulted in somewhat lower activities. The decay of reparability, however, was found to progress more slowly than post-irradiation inactivation itself. After completion of repair the activities of repaired samples did not decrease significantly. 2. The presence of specific additives during irradiation caused significant protective effects against primary inactivation. The protection by formate was very pronounced (e.g., Asub(r)=72% and D 37 =6 kGy for 100 mM formate). The presence of catalytic amounts of superoxide dismutase and/or catalase exhibited only minor effects, depending on the presence and concentration of formate. (orig.)

  4. Post-irradiation effects in CMOS integrated circuits

    International Nuclear Information System (INIS)

    Zietlow, T.C.; Barnes, C.E.; Morse, T.C.; Grusynski, J.S.; Nakamura, K.; Amram, A.; Wilson, K.T.

    1988-01-01

    The post-irradiation response of CMOS integrated circuits from three vendors has been measured as a function of temperature and irradiation bias. The author's have found that a worst-case anneal temperature for rebound testing is highly process dependent. At an anneal temperature of 80 0 C, the timing parameters of a 16K SRAM from vendor A quickly saturate at maximum values, and display no further changes at this temperature. At higher temperature, evidence for the anneal of interface state charge is observed. Dynamic bias during irradiation results in the same saturation value for the timing parameters, but the anneal time required to reach this value is longer. CMOS/SOS integrated circuits (vendor B) were also examined, and showed similar behavior, except that the saturation value for the timing parameters was stable up to 105 0 C. After irradiation to 10 Mrad(Si), a 16K SRAM (vendor C) was annealed at 80 0 C. In contrast to the results from the vendor A SRAM, the access time decreased toward prerad values during the anneal. Another part irradiated in the same manner but annealed at room temperature showed a slight increase during the anneal

  5. Protection against post-irradiation oxygen-dependent damage in barley seeds by catalase and hydrogen peroxide: probable radiation chemistry

    International Nuclear Information System (INIS)

    Singh, S.P.; Kesavan, P.C.

    1990-01-01

    Influence of varying concentration of catalase and H 2 O 2 administered individually and in combination treatment during post-hydration on the oxygen-dependent and -independent pathways of damage was assessed in dry barley seeds irradiated in vacuo with 350 Gy of 60 Co gammarays. Both catalase (100 to 500 units/ml) and H 2 O 2 (0.001 to 0.1 mM) afforded significant radioprotection against the post-irradiation O 2 -dependent damage. However, a combination treatment (300 units/ml of catalase and 0.01 mM of H 2 O 2 ) afforded significantl y more protection than either of the additives individually. None of the concentrations of catalase exerted any effect on the O 2 -independent pathway, whereas H 2 O 2 at higher concentrations (1 and 10 mM) significantly potentiated both the O 2 -dependent as well as the -independent components of radiation damage. These observations are better explicable in terms of radiation chemistry. (author). 16 refs., 3 tabs

  6. Effect of medium and post-irradiation storage on rooting of irradiated onions

    International Nuclear Information System (INIS)

    Singh, Rita

    2000-01-01

    Rooting test for detection of irradiation in onion bulbs was studied. Onions were exposed to different dose levels of 30, 60, 90, 120 and 150 Gy. The effects of irradiation dose, cultivar difference, rooting medium and post-irradiation storage on the rooting were investigated. The number and the length of the roots formed in onions were found to decrease on irradiation. The effect was more at higher doses. The effect of irradiation on rooting was also evident after 120 days of storage. (author)

  7. Post-irradiation diarrhea

    International Nuclear Information System (INIS)

    Meerwaldt, J.H.

    1984-01-01

    In radiotherapy of pelvic cancers, the X-ray dose to be delivered to the tumour is limited by the tolerance of healthy surrounding tissue. In recent years, a number of serious complications of irradiation of pelvic organs were encountered. Modern radiotherapy necessitates the acceptance of a calculated risk of complications in order to achieve a better cure rate. To calculate these risks, one has to know the radiation dose-effect relationship of normal tissues. Of the normal tissues most at risk when treating pelvic tumours only the bowel is studied. In the literature regarding post-irradiation bowel complications, severe and mild complications are often mixed. In the present investigation the author concentrated on the group of patients with relatively mild symptoms. He studied the incidence and course of post-irradiation diarrhea in 196 patients treated for carcinoma of the uterine cervix or endometrium. The aims of the present study were: 1) to determine the incidence, course and prognostic significance of post-irradiation diarrhea; 2) to assess the influence of radiotherapy factors; 3) to study the relation of bile acid metabolism to post-irradiation diarrhea; 4) to investigate whether local factors (reservoir function) were primarily responsible. (Auth.)

  8. Effects of ablation energy and post-irradiation on the structure and properties of titanium dioxide nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Guillén, G. García [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66455, México (Mexico); Shaji, S., E-mail: sshajis@yahoo.com [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66455, México (Mexico); Universidad Autónoma de Nuevo León-CIIDIT, Apodaca, Nuevo León, México (Mexico); Palma, M. I. Mendivil [Centro de Investigación en Materiales Avanzados (CIMAV), Unidad Monterrey, PIIT, Apodaca, Nuevo León, México (Mexico); Avellaneda, D.; Castillo, G.A.; Roy, T.K. Das [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66455, México (Mexico); and others

    2017-05-31

    Highlights: • Highlights • TiO{sub 2} nanomaterials were prepared by PLALM. • Characterized these nanomaterials using TEM, XPS, XRD, optical and luminescence measurements. • Morphology of these nanomaterials were dependent on ablation wavelength, fluence and post-irradiation time. • Laser post irradiation modified the size, morphology and structure of these TiO{sub 2} nanomaterials. - Abstract: Nanomaterials of titanium oxide were prepared by pulsed laser ablation of a titanium metal target in distilled water. The ablation was performed at different laser energy (fluence) using a nanosecond pulsed Nd:YAG laser output of 1064 and 532 nm. A post-irradiation of titanium oxide nanocolloids obtained by ablation using 532 nm was carried out to explore its effects on the structure and properties. Analysis of morphology, crystalline phase, elemental composition, chemical state, optical and luminescent properties were performed using Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), UV–-vis absorption spectroscopy and room temperature photoluminescence spectroscopy. It was found that titanium oxide nanomaterial morphologies and optical properties were determined by ablation wavelength and fluence. Further, nanocolloids prepared by 532 nm ablation showed a crystalline phase change by laser post-irradiation. The results showed that pulsed laser ablation in liquid as well as post-irradiation were effective in modifying the final structure and properties of titanium oxide nanocolloids.

  9. Effects of ablation energy and post-irradiation on the structure and properties of titanium dioxide nanomaterials

    International Nuclear Information System (INIS)

    Guillén, G. García; Shaji, S.; Palma, M. I. Mendivil; Avellaneda, D.; Castillo, G.A.; Roy, T.K. Das

    2017-01-01

    Highlights: • Highlights • TiO_2 nanomaterials were prepared by PLALM. • Characterized these nanomaterials using TEM, XPS, XRD, optical and luminescence measurements. • Morphology of these nanomaterials were dependent on ablation wavelength, fluence and post-irradiation time. • Laser post irradiation modified the size, morphology and structure of these TiO_2 nanomaterials. - Abstract: Nanomaterials of titanium oxide were prepared by pulsed laser ablation of a titanium metal target in distilled water. The ablation was performed at different laser energy (fluence) using a nanosecond pulsed Nd:YAG laser output of 1064 and 532 nm. A post-irradiation of titanium oxide nanocolloids obtained by ablation using 532 nm was carried out to explore its effects on the structure and properties. Analysis of morphology, crystalline phase, elemental composition, chemical state, optical and luminescent properties were performed using Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), UV–-vis absorption spectroscopy and room temperature photoluminescence spectroscopy. It was found that titanium oxide nanomaterial morphologies and optical properties were determined by ablation wavelength and fluence. Further, nanocolloids prepared by 532 nm ablation showed a crystalline phase change by laser post-irradiation. The results showed that pulsed laser ablation in liquid as well as post-irradiation were effective in modifying the final structure and properties of titanium oxide nanocolloids.

  10. Neutron, gamma ray and post-irradiation thermal annealing effects on power semiconductor switches

    International Nuclear Information System (INIS)

    Schwarze, G.E.; Frasca, A.J.

    1994-01-01

    The effects of neutrons and gamma rays on the electrical and switching characteristics of power semiconductor switches must be known and understood by the designer of the power conditioning, control, and transmission subsystem of space nuclear power systems. The SP-100 radiation requirements at 25 m from the nuclear source are a neutron fluence of 10 13 n/cm 2 and a gamma dose of 0.5 Mrads. Experimental data showing the effects of neutrons and gamma rays on the performance characteristics of power-type NPN Bipolar Junction Transistors (BJTs), Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs), and Static Induction Transistors (SITs) are given in this paper. These three types of devices were tested at radiation levels which met or exceeded the SP-100 requirements. For the SP-100 radiation requirements, the BJTs were found to be most sensitive to neutrons, the MOSFETs were most sensitive to gamma rays, and the SITs were only slightly sensitive to neutrons. Post-irradiation thermal anneals at 300 K and up to 425 K were done on these devices and the effectiveness of these anneals are also discussed

  11. Neutron, gamma ray and post-irradiation thermal annealing effects on power semiconductor switches

    Science.gov (United States)

    Schwarze, G. E.; Frasca, A. J.

    1991-01-01

    The effects of neutron and gamma rays on the electrical and switching characteristics of power semiconductor switches must be known and understood by the designer of the power conditioning, control, and transmission subsystem of space nuclear power systems. The SP-100 radiation requirements at 25 m from the nuclear source are a neutron fluence of 10(exp 13) n/sq cm and a gamma dose of 0.5 Mrads. Experimental data showing the effects of neutrons and gamma rays on the performance characteristics of power-type NPN Bipolar Junction Transistors (BJTs), Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs), and Static Induction Transistors (SITs) are presented. These three types of devices were tested at radiation levels which met or exceeded the SP-100 requirements. For the SP-100 radiation requirements, the BJTs were found to be most sensitive to neutrons, the MOSFETs were most sensitive to gamma rays, and the SITs were only slightly sensitive to neutrons. Post-irradiation thermal anneals at 300 K and up to 425 K were done on these devices and the effectiveness of these anneals are also discussed.

  12. Role of post irradiation growth delay in chemical radioprotection by caffeine

    International Nuclear Information System (INIS)

    Gangabhagirathi, R.; Rao, B.S.; Bhat, N.N.

    2004-01-01

    Post irradiation treatment with caffeine enhanced the survival of wild type diploid yeast strain, Saccharomyces cerevisiae X2180. The presence of caffeine during gamma irradiation also affected a similar enhancement in survival. These observations suggest that caffeine imparted significant protection against radiation. Effectiveness of caffeine, even when present only during the post irradiation period, suggests that it modulates the post irradiation recovery process in yeast cells. (author)

  13. Irradiation and Post-Irradiation Storage of Chicken: Effects on Fat and Proteins

    International Nuclear Information System (INIS)

    Abou-Tarboush, H.M.; Al-Kahtani, H.A.; Abou-Arab, A.A.; Atia, M.; Bajaber, A.S.; Ahmed, M.A.; El-Mojaddidi, M.A.

    1997-01-01

    Chicken were subjected to gamma irradiation doses of 2.5, 5.0, 7.5 and 10.0 KGy and post-irradiation storage of 21 days at 4±2º. The effects on fat and protein of chicken were studied. Rate of formation of total volatile basic-nitrogen was less in irradiated samples particularly in samples treated with 5.0KGy during the entire storage. Fatty acid profiles of chicken lipids were not significantly (P≤ 0.05) affected by irradiation especially at doses of 5.0 KGy. However, irradiation caused a large increase in thiobarbituric acid (TBA) values which continued gradually during storage. Changes in amino acids were minimal. Irradiated and unirradiated samples showed the appearance of protein subunits with molecular weights in the range of 10.0 to 88.0 and 10.0 to 67.0 KD, respectively. No changes were observed in the sarcoplasmic protein but the intensity of bands in all irradiated samples decreased after 21 days of storage

  14. Molecular structure effects on the post irradiation diffusion in polymer gel dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Mattea, F.; Romero, M.; Strumia, M. [Instituto Multidisciplinario de Biologia Vegetal / CONICET, Universidad Nacional de Cordoba, Departamento de Quimica Organica, Ciudad Universitaria, 5000 Cordoba (Argentina); Vedelago, J. [Laboratorio de Investigaciones e Instrumentacion en Fisica Aplicada a la Medicina e Imagenes por Rayos X, Laboratorio 448 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina); Quiroga, A. [Centro de Investigacion y Estudios de Matematica / CONICET, Oficina 318 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina); Valente, M., E-mail: fmattea@gmail.com [Instituto de Fisica E. Gaviola / CONICET, LIIFAMIRx, Oficina 102 FaMAF - UNC, 5000 Cordoba (Argentina)

    2014-08-15

    Polymer gel dosimeters have specific advantages for recording 3D radiation dose distribution representing a key factor for most of the therapeutic and diagnostic radiation techniques. Radiation-induced polymerization and crosslinking reactions that take place in the dosimeter have been studied for different monomers like acrylamide and N,N-methylene-bis acrylamide (Bis) and most recently for less toxic monomers like N-isopropylacrylamide and Bis. In this work a novel system based on itaconic acid and Bis is proposed, the radical polymerization or gel formation of these monomers has been already studied for the formation of an hydrogel for non dosimetric applications and their reactivity are comparable with the already mentioned systems. Although the 3D structure is maintained after the dosimeter has been irradiated, it is not possible to eliminate the diffusion of the reacted and monomer species in regions of dose gradients within the gel after irradiation. As a consequence the dose information of the dosimeters loose quality over time. The mobility within the gelatin structure of the already mentioned species is related to their chemical structure, and nature. In this work the effect of changes in the chemical structure of the monomers over the dosimetric sensitivity and over the post-irradiation diffusion of species is studied. One of the acrylic acid groups of the itaconic acid molecule is modified to obtain molecules with similar reactivity but different molecular sizes. Dosimetric systems with these modified species, Bis, an antioxidant to avoid oxygen polymerization inhibition, water and gelatin are irradiated in an X-ray tomography at different doses, and the resulting dosimeters are characterized by Raman spectroscopy and optical absorbance to study their feasibility and capabilities as dosimetric systems, and by optical-CT to analyze the diffusion degree after being irradiated. (Author)

  15. Molecular structure effects on the post irradiation diffusion in polymer gel dosimeters

    International Nuclear Information System (INIS)

    Mattea, F.; Romero, M.; Strumia, M.; Vedelago, J.; Quiroga, A.; Valente, M.

    2014-08-01

    Polymer gel dosimeters have specific advantages for recording 3D radiation dose distribution representing a key factor for most of the therapeutic and diagnostic radiation techniques. Radiation-induced polymerization and crosslinking reactions that take place in the dosimeter have been studied for different monomers like acrylamide and N,N-methylene-bis acrylamide (Bis) and most recently for less toxic monomers like N-isopropylacrylamide and Bis. In this work a novel system based on itaconic acid and Bis is proposed, the radical polymerization or gel formation of these monomers has been already studied for the formation of an hydrogel for non dosimetric applications and their reactivity are comparable with the already mentioned systems. Although the 3D structure is maintained after the dosimeter has been irradiated, it is not possible to eliminate the diffusion of the reacted and monomer species in regions of dose gradients within the gel after irradiation. As a consequence the dose information of the dosimeters loose quality over time. The mobility within the gelatin structure of the already mentioned species is related to their chemical structure, and nature. In this work the effect of changes in the chemical structure of the monomers over the dosimetric sensitivity and over the post-irradiation diffusion of species is studied. One of the acrylic acid groups of the itaconic acid molecule is modified to obtain molecules with similar reactivity but different molecular sizes. Dosimetric systems with these modified species, Bis, an antioxidant to avoid oxygen polymerization inhibition, water and gelatin are irradiated in an X-ray tomography at different doses, and the resulting dosimeters are characterized by Raman spectroscopy and optical absorbance to study their feasibility and capabilities as dosimetric systems, and by optical-CT to analyze the diffusion degree after being irradiated. (Author)

  16. Post irradiation effects on the graft of poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) films

    International Nuclear Information System (INIS)

    Geraldes, Adriana N.; Zen, Heloisa A.; Ribeiro, Geise; Ferreira, Henrique P.; Souza, Camila P.; Parra, Duclerc F.; Lugao, Ademar B.

    2009-01-01

    Radiation induced grafting of monomers into fluorinated polymers was designed as an alternative route to polymer modification. In this work, grafting of styrene onto poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) was studied. Radiation-induced grafting of styrene onto PFA films was investigated after simultaneous irradiation (in post-irradiation condition) using a 60 Co source. The films of PFA were irradiated at 20, 40, 80 and 100 kGy doses at room temperature and chemical changes were monitored after contact with styrene for grafting. The post-irradiation time was established between 7 and 28 days when films of PFA were maintained in styrene/toluene 1:1 v/v solution at room temperature. After these periods the grafting degrees were evaluated in the samples. The highest degree of grafting was achieved after 14 days. Chemical modifications were evaluated by infrared spectroscopic analysis (FTIR), thermogravimetry (TG), differential scanning calorimetry (DSC) and also by scanning electron microscopy (SEM). The degree of grafting (DOG) was determined gravimetrically. The results showed that irradiated PFA films at 100 kGy exhibited higher grafting degree. Surface analysis by SEM technique of irradiated, grafted and original films have presented an homogeneous surface. (author)

  17. Effects of post-irradiation annealing on the transformation behavior of Ti-Ni alloys

    International Nuclear Information System (INIS)

    Kimura, A.; Tsuruga, H.; Morimura, T.; Misawa, T.; Miyazaki, S.

    1993-01-01

    Recovery processes of martensitic transformation of neutron irradiated Ti-50.0, 50.5 and 51.0 at.%Ni alloys during post-irradiation annealing were investigated by means of differential scanning calorimetry (DSC), tensile tests and transmission electron microscope (TEM) observations. Neutron irradiation up to a fluence of 1.2x10 24 n/cm 2 at 333 K suppressed the martensitic transformation as well as the stress-induced martensitic transformation of these alloys above 150 K. The TEM observations revealed that the disordered zones containing small defect clusters in high density were formed in the neutron irradiated Ti-Ni alloys. The DSC measurements also showed that the post-irradiation annealing caused recovery of the transformation of which the progress depended on the annealing temperature and period. A significant retardation of the recovery was recognized in the Ti-51.0 at.%Ni alloy in comparison with the Ti-50.0 at.%Ni alloy. From the shifts in the transformation temperature upon isothermal annealing at various annealing temperatures, the activation energies of the recovery process of the transformation in the neutron irradiated Ti-50.0 and 51.0 at.%Ni alloys were evaluated by a cross-cut method to be 1.2 eV and 1.5 eV, respectively. The recovery of the transformation was ascribed to the re-ordering resulting from decomposition of vacancy clusters, and those obtained values of the activation energy were considered to be the sum of the migration energy of vacancy and the binding energy of vacancy-vacancy cluster. The retardation of the recovery in the Ti-51.0 at%Ni alloy was interpreted in terms of large binding energy in this alloy due to the off-stoichiometry. (author)

  18. A Study on the Pre-and Post-irradiation Effect of Blood Vessels in the Experimentally Induced Tongue Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Tae; Park, Tae Won [Dept. of Oral Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1990-02-15

    The author observed the changes of vasculature of pre-and post-irradiation on DMBA induced rat tongue cancer. The study was performed by using vascular corrosion resin casting, and scanning electron microscopy. The results were as follows. 1. The capillaries runned parallely and formed bundles and, sometimes, plexus. The endothelial cells were arranged regularly and small pores were observed. 2. In irradiated normal tongue the capillaries were curved slightly and formed plexus on initial day of post-irradiation. On third day the capillaries and capillary pores were dilated and the endothelial cell arrangement was irregular. The effects of irradiation were gradually increased from initial to the 3rd day, though it was decreased after 7th day. 3. The vasculature of DMBA induced tongue cancer group were very irregular, and large avascular lesions were formed according to the cancer necrosis or tumor cell nest and the vasculature was narrowed and paralleled around the avascular lesion by compression of cancer cell nest. The vascular wall was roughened and dilated, forming club shaped or varix. 4. The vessels were curved and formed reticular network in irradiated DMBA induced tongue carinoma group. The free end of newly formed capillaries had regular width, and also irregular club shaped or aneurysmal dilation were observed. The vascular structures were destroyed and vessels were fused in tumor necrosis lesion. The radiation effects were marked on the first and third day of irradiation and the effects were decreased after seventh day and showed capillary regeneration.

  19. Solvent effect on post-irradiation grafting of styrene onto poly(ethylene-alt-tetrafluoroethylene) (ETFE) films

    Science.gov (United States)

    Napoleão Geraldes, Adriana; Augusto Zen, Heloísa; Ribeiro, Geise; Fernandes Parra, Duclerc; Benévolo Lugão, Ademar

    2013-03-01

    Radiation-induced grafting of styrene onto ETFE films in different solvent was investigated after simultaneous irradiation (in post-irradiation condition) using a 60Co source. Grafting of styrene followed by sulfonation onto poly(ethylene-alt-tetrafluoroethylene) (ETFE) are currently studied for synthesis of ion exchange membranes. The ETFE films were immersed in styrene/toluene, styrene/methanol and styrene/isopropyl alcohol and irradiated at 20 and 100 kGy doses at room temperature. The post-irradiation time was established at 14 day and the grafting degree was evaluated. The grafted films were sulfonated using chlorosulfonic acid and 1,2-dichloroethane 20:80 (v/v) at room temperature for 5 h. The degree of grafting (DOG) was determined gravimetrically and physical or chemical changes were evaluated by differential scanning calorimeter analysis (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The ion exchange capacity (IEC) values showed the best performance of sulfonation for ETFE membranes grafted in toluene solvent. Surface images of the grafted films by SEM technique have presented a strong effect of the solvents on the films morphology.

  20. Post irradiation effect on some antiphagocytic substances produced by pathogenic microorganisms

    International Nuclear Information System (INIS)

    Shehata, M.M.K.

    2003-01-01

    Some clinical isolated microorganiams can produce antiphagocytic virulence substance. In this study 43 bacterial strains were isolated from cervix of 50 patients. Escheruchia coli was the most common species isolated (39.53%) followed by Klebsiella pneumoniae (23.26), Pseudomonas aeruginosa (11.63%), Proteus mirabilis (9.30%), Klebsiella oxytoca (4.65%), Staphylococcus warneri (4.65%), Klebsiella group 47 (2.33%), Morganella morganii (2.33%) and Staphylococcus hominis (2.33%) four yeast fungal organisms were isolated in this study Candida albicans was the only Candida species isolated representing 8.51% of total number of pathogenic bacteria and yeast fungi isolated. Radiotherapy of these cancer patients had many effects on the microbial cells. The tested isolates were exposed to in-vivo multiple fractionated doses 10-50Gy and in-vitro single equivalent dose 7.04-20Gy. The isolated strains were tested for antimicrbial agent susceptibility using 18 different antibiotics for bacterial isolates and anystatin for Candida albicans. The effect of bacterial and yeast fungal virulence factors on neutrophil phagocytosis and antimicrobial activity was examined. Disk susceptibility testing suggested that, the isolated producer strains which were positive for extracellular proteinase enzyme and/or for slime production that correlate with infectivity were resistant to erythromycin, streptomycin, neomycin, kanamycin, tetracycline, cephalothin and sulphamethoxazol/trimethoprim and rarely susceptible to amoxicillin /clavulanic acid and cefotaxime. In contrast, many non-producer strains were susceptible to most of the tested antibiotics with marked variability among species. In case of Candida albicans all the tested strains were susceptible to the tested antimycotic agent used before and after in-vitro irradiation at a dose level of 20gy. It was found that slime substance and/or proteinase enzyme reduced the phagocytic activity of the leukocytes against the producer bacterial

  1. Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper

    International Nuclear Information System (INIS)

    Singh, B.N.; Edwards, D.J.; Toft, P.

    2001-01-01

    Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Risoe at 100 deg. C to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 deg. C whereas others were given a post-irradiation annealing treatment at 300 deg. C for 50 h and subsequently tested at 100 deg. C. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model

  2. Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N. E-mail: bachu.singh@risoe.dk; Edwards, D.J.; Toft, P

    2001-12-01

    Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Risoe at 100 deg. C to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 deg. C whereas others were given a post-irradiation annealing treatment at 300 deg. C for 50 h and subsequently tested at 100 deg. C. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model.

  3. Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper

    Science.gov (United States)

    Singh, B. N.; Edwards, D. J.; Toft, P.

    2001-12-01

    Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Risø at 100 °C to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 °C whereas others were given a post-irradiation annealing treatment at 300 °C for 50 h and subsequently tested at 100 °C. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model.

  4. TEM examination of the effect of post-irradiation annealing on 7.7 dpa AISI 304 stainless steel

    International Nuclear Information System (INIS)

    Karlsen, W.; Ivanchenko, M.; Pakarinen, J.; Karlsen, T.

    2015-01-01

    Stainless steels exposed to neutron irradiation during service in light water reactors (LWR) can become susceptible to intergranular cracking, referred to as irradiation assisted stress corrosion cracking (IASCC). Analytical transmission electron microscopy (ATEM) was used to examine the effect of post-irradiation annealing (PIA) on radiation-induced segregation (RIS) at the grain boundaries of 7.7 dpa AISI 304 stainless steel. The grain boundary profiles and the irradiation damage were analysed in the as-irradiated state and after PIA of 6 hours at 500 C. degrees and after 25 hours at 500 C. degrees and 550 C. degrees by using transmission electron microscopy (TEM). As a main conclusion from the TEM examinations, the effects of PIA were found to be relatively small after only 6 hours, while after 25 hours of PIA at both 500 and 550 C. degrees, RIS was almost recovered and only marginal deviation in chemical composition could be found near the GB. The as-irradiated state showed extreme RIS values of Si 4.9 wt%, Cr 14.7 wt%, Ni 23.4 wt%, and P 1.4 wt%., while upon PIA for 6 hours the extreme values for RIS were Si 3.9 wt%, Cr 16.0 wt%, Ni 21 wt%, and P 0.9 wt%. After 6 hours annealing at 500 C. dislocation loops start to grow, while dislocation density remains of the same order of magnitude. After annealing for 25 hours at 500 C. degrees the average size of dislocation loops remains nearly the same, while dislocation density was reduced almost by one fold. In the areas where dislocation density was found to be the lowest some features, which can most likely be attributed to stacking fault tetrahedral (SFT) were found. Annealing at even higher temperature (550 C.) affected the average size of the dislocation loops, making them almost twice as large as well as resulting in a very broad distribution of dislocation sizes. Density of dislocations is also reduced by one fold in comparison to the as irradiated condition and leads to formation of SFTs, which could be

  5. Effect of the hydrolytic state of dietary protein on post-irradiation morbidity and mucosal cell regeneration

    International Nuclear Information System (INIS)

    Beitler, M.K.; Mahler, P.A.; Yamanaka, W.K.; Guy, D.G.; Hutchinson, M.L.

    1987-01-01

    Diets containing hydrolyzed casein have been observed to enhance post-irradiation intestinal mucosal recovery. The intake and the composition of such diets were not carefully controlled. This study attempted to do so. Male specific pathogen-free Sprague-Dawley rats were randomized to receive either an enzymatically hydrolyzed casein semi-purified diet (EHC), a whole casein semi-purified diet (WC), or powdered lab chow (C). All diets were isonitrogenous, and the WC and C rats were pair-fed to the ad libitum fed EHC rats. Seven days after initiation of feeding, the rats were abdominally irradiated with a single 9.0 Gy dose of 137Cs gamma rays. The rats were continued on the diets for another 5 days. Intestinal mucosa from transverse segments at the duodenum, jejunum, proximal ileum, and distal ileum were measured for incorporation of ( 3 H methyl) thymidine 1 hour after intraperitoneal injection. Incorporation reached a maximum by day 4 post-irradiation regardless of diet or segment. Incorporation in the duodenum was enhanced by the EHC diet compared to the C diet, while the incorporation in the jejunum was initially suppressed by the EHC diet compared to the WC diet. In the jejunum, the number of mitoses per crypt of 25 anti-mesenteric crypts post-irradiation was increased by the EHC diet. Prior to irradiation, all groups gained similar amounts of weight. After irradiation, the C rats lost weight, while the EHC and WC rats remained the same or gained weight. Guaiac tests for occult blood were negative prior to irradiation, but positive for all rats on days 1-5 postirradiation. When calorie and protein intakes were controlled, different areas of the small intestine responded differently to EHC

  6. Post irradiation examination technology exchange

    International Nuclear Information System (INIS)

    Sozawa, Shizuo; Ito, Masayasu; Taguchi, Taketoshi; Nakagawa, Tetsuya; Lee, Hyung-Kwon

    2012-01-01

    Under the KAERI and JAEA agreement, in a part of the program 18 (Post Irradiation Examination (PIE) and Evaluation Technique of Irradiated Materials), an eddy current test was proposed as a round robin test, and it has been being progressed in both organizations in order to enhance the post irradiation examination technology. Up to now, several data are obtained by both PIE facilities. In this paper, the round robin test program is shown, and also shown obtained data with discussion from applicability as a nondestructive test in the hot cell. (author)

  7. Alkali-labile sites and post-irradiation effects in single-stranded DNA induced by H radicals

    International Nuclear Information System (INIS)

    Lafleur, M.V.M.; Heuvel, N. van; Woldhuis, J.; Loman, H.

    1978-01-01

    Single-stranded phiX174 DNA in aqueous solutions has been irradiated in the absence of oxygen, under conditions in which H radicals react with the DNA. It was shown that H radical reactions result in breaks, which contribute approximately 10 per cent inactivation. Further, two types of alkali-labile sites were formed. One was lethal and gave rise to single-strand breaks by alkali and was most probably identical with post-irradiation heat damage and contributed about 33 per cent to the inactivation mentioned above. The other consisted of non-lethal damage, partly dihydropyrimidine derivatives, and was converted to lethal damage by alkali. This followed from experiments in which the DNA was treated with osmium-tetroxide, which oxidized thymine to 5,6-dihydroxydihydrothymine. Treatment with alkali of this DNA gave the same temperature dependence as found for the non-lethal alkali-labile sites in irradiated DNA. A similar temperature dependence was found for dihydrothymine and irradiated pyrimidines with alkali. (author)

  8. The yield of fission neutron-induced chromatid aberrations in G[sub 2]-stage human lymphocytes: effect of caffeine, hydroxyurea and cytosine arabinoside post-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Antoccia, A.; Tanzarella, C. (La Sapienza Univ., Rome (Italy)); Palitti, F. (Tuscia Univ., Viterbo (Italy) La Sapienza Univ., Rome (Italy)); Raggi, T. (Tuscia Univ., Viterbo (Italy)); Catena, C. (ENEA, Casaccia (Italy). Centro Ricerche Energia)

    1992-11-01

    To evaluate the influence of inhibitors of DNA synthesis/repair on the yield of chromosomal aberrations in the G[sub 2] phase of the cell cycle, whole-blood cultures of human lymphocytes were exposed to various doses of fission neutrons or X-rays and treated post-irradiation during the last 2.45 h before harvesting, with 5mM hydroxyurea (HU) and 0.05 mM cytosine arabinoside (ara-C). The presence of caffeine and HU strongly potentiated the yield of chromatid-type aberrations induced by both neutrons and X-rays. No potentiating effect, except at the highest dose of neutrons, was observed when irradiated cells were subsequently treated with ara-C. In addition, neutron-induced mitotic delay was shortened by treatment with caffeine, mainly within the first 2 h after irradiation. (Author).

  9. The molecular cues for the biological effects of ionizing radiation dose and post-irradiation time on human breast cancer SKBR3 cell line: A Raman spectroscopy study.

    Science.gov (United States)

    Jafarzadeh, Naser; Mani-Varnosfaderani, Ahmad; Gilany, Kambiz; Eynali, Samira; Ghaznavi, Habib; Shakeri-Zadeh, Ali

    2018-03-01

    Radiotherapy is one of the main modalities of cancer treatment. The utility of Raman spectroscopy (RS) for detecting the distinct radiobiological responses in human cancer cells is currently under investigation. RS holds great promises to provide good opportunities for personalizing radiotherapy treatments. Here, we report the effects of the radiation dose and post-irradiation time on the molecular changes in the human breast cancer SKBR3 cells, using RS. The SKBR3 cells were irradiated by gamma radiation with different doses of 0, 1, 2, 4, and 6 Gy. The Raman signals were acquired 24 and 48 h after the gamma radiation. The collected Raman spectra were analyzed by different statistical methods such as principal component analysis, linear discriminant analysis, and genetic algorithm. A thorough analysis of the obtained Raman signals revealed that 2 Gy of gamma radiation induces remarkable molecular and structural changes in the SKBR3 cells. We found that the wavenumbers in the range of 1000-1400 cm -1 in Raman spectra are selective for discriminating between the effects of the different doses of irradiation. The results also revealed that longer post-irradiation time leads to the relaxation of the cells to their initial state. The molecular changes that occurred in the 2Gy samples were mostly reversible. On the other hand, the exposure to doses higher than 4Gy induced serious irreversible changes, mainly seen in 2700-2800 cm -1 in Raman spectra. The classification models developed in this study would help to predict the radiation-based molecular changes induced in the cancer cells by only using RS. Also, this designed framework may facilitate the process of biodosimetry. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Biochemical effects of heat shock and caffeine on post-irradiation oxic and anoxic damage in barley seeds of low and high water content

    International Nuclear Information System (INIS)

    Singh, S.P.; Kesavan, P.C.

    1991-01-01

    Wet heat shock (60 o C, 90s) and caffeine (3.8 x 10 -4 M) afford significant radioprotection against post-irradiation O 2 -dependent damage which develops in seeds of ∼ 3.5% moisture content. The damage was assessed in terms of seedling injury on the eighth day of growth. An increase in seedling injury is clearly seen, associated with a parallel increase in the peroxidase activity. There is a concomitant decrease in the content of total peroxides. Both these post-irradiation treatments potentiate the O 2 -independent component of seedling injury, irrespective of the seed moisture content. Analysis of the peroxidase activity in the seedlings using non-denaturing polyacrylamide gel electrophoresis reveals that two additional bands appear with the post-irradiation oxic damage. Radioprotection against this damage by caffeine, heat shock and O 2 -free post-irradiation hydration is accompanied by the disappearance of these two additional bands. (author)

  11. AGR-1 Post Irradiation Examination Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-08-01

    The post-irradiation examination (PIE) of the Advanced Gas Reactor (AGR)-1 experiment was a multi-year, collaborative effort between Idaho National Laboratory (INL) and Oak Ridge National Laboratory (ORNL) to study the performance of UCO (uranium carbide, uranium oxide) tristructural isotropic (TRISO) coated particle fuel fabricated in the U.S. and irradiated at the Advanced Test Reactor at INL to a peak burnup of 19.6% fissions per initial metal atom. This work involved a broad array of experiments and analyses to evaluate the level of fission product retention by the fuel particles and compacts (both during irradiation and during post-irradiation heating tests to simulate reactor accident conditions), investigate the kernel and coating layer morphology evolution and the causes of coating failure, and explore the migration of fission products through the coating layers. The results have generally confirmed the excellent performance of the AGR-1 fuel, first indicated during the irradiation by the observation of zero TRISO coated particle failures out of 298,000 particles in the experiment. Overall release of fission products was determined by PIE to have been relatively low during the irradiation. A significant finding was the extremely low levels of cesium released through intact coatings. This was true both during the irradiation and during post-irradiation heating tests to temperatures as high as 1800°C. Post-irradiation safety test fuel performance was generally excellent. Silver release from the particles and compacts during irradiation was often very high. Extensive microanalysis of fuel particles was performed after irradiation and after high-temperature safety testing. The results of particle microanalysis indicate that the UCO fuel is effective at controlling the oxygen partial pressure within the particle and limiting kernel migration. Post-irradiation examination has provided the final body of data that speaks to the quality of the AGR-1 fuel, building

  12. Post-irradiation degradation of DNA in electron and neutron-irradiated E. coli B/r; the effect of the radiation sensitizer metronidazole

    Energy Technology Data Exchange (ETDEWEB)

    Cramp, W A; George, A M; Howlett, J [Hammersmith Hospital, London (UK). M.R.C. Cyclotron Unit

    1976-04-01

    Suspensions of E.coli B/r were irradiated under aerobic and anoxic conditions with electrons (7 to 8 MeV, 2 and 20 krad/min, MRC linear accelerator), or with neutrons (average energy 7.5 MeV, 2 krad/min, MRC cyclotron) in an investigation of the effects of the radiosensitizer, metronidazole (Flagyl, 5 or 10 mM) on survival and DNA degradation. These results are compared with those for another electron affinic radiosensitizer, indane trione. Survival studies yielded enhancement ratios, for anoxic irradiation only, of 1.7 (5mM) and 1.9 (10mM) for electrons, and 1.2 (5mM and 10mM) for neutrons. Unlike indane trione, metronidazole had no pronounced inhibitory effect on post-irradiation DNA degradation, either when incubated with the bacteria before irradiation or when present during irradiation. When present under anoxic conditions of irradiation with electrons, some enhancement of degradation was observed. DNA degradation was reduced at higher doses, with a pronounced maxiumum effect, for neutrons as well as for electrons. Metronidazole allowed this degradation to continue and showed some sensitizing action, but did not prevent the decrease in total degradation at high doses. It is therefore difficult to correlate DNA degradation with cell-depth.

  13. Peculiarities in mice embriogenesis under serotonin effect in pre- and post-irradiation period in prenervous period of development

    International Nuclear Information System (INIS)

    Konstantinova, M.M.; Panaeva, S.V.; Podmareva, O.N.; Turpaev, T.M.

    1995-01-01

    Effect of serotonin and X-ray irradiation on mice embriogenesis in prenervous period of development is studied. The above factors were applied separately and in combination (in various doses, with change of sequence). It is shown that development of embriotoxic effect of serotonin is determined by embryos age. Six-day embryos are most sensitive. Eight-day embryos are characterized by absence of toxic effect of serotonin doses applied. The eighth day embryos are most radiosensitive, whereas the six-day ones are less radiosensitive. Serotonin administered to mice females before and after irradiation on the eight day of pregnancy produced radioprotective and therapeutic effect, and on the sixth-seventh days intensified negative radiation consequences. 15 refs.; 2 tabs

  14. Biochemical effects of heat shock and caffeine on post-irradiation oxic and anoxic damage in barley seeds of low and high water content

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.; Kesavan, P.C. (Jawaharlal Nehru Univ., New Delhi (India). School of Life Sciences)

    1991-05-01

    Wet heat shock (60{sup o}C, 90s) and caffeine (3.8 x 10{sup -4}M) afford significant radioprotection against post-irradiation O{sub 2}-dependent damage which develops in seeds of {similar to} 3.5% moisture content. The damage was assessed in terms of seedling injury on the eighth day of growth. An increase in seedling injury is clearly seen, associated with a parallel increase in the peroxidase activity. There is a concomitant decrease in the content of total peroxides. Both these post-irradiation treatments potentiate the O{sub 2}-independent component of seedling injury, irrespective of the seed moisture content. Analysis of the peroxidase activity in the seedlings using non-denaturing polyacrylamide gel electrophoresis reveals that two additional bands appear with the post-irradiation oxic damage. Radioprotection against this damage by caffeine, heat shock and O{sub 2}-free post-irradiation hydration is accompanied by the disappearance of these two additional bands. (author).

  15. Effects of bonding bakeout thermal cycles on pre- and post irradiation microstructures, physical, and mechanical properties of copper alloys

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N.; Eldrup, M.; Toft, P.; Edwards, D.J. [Pacific Northwest National Laboratory, Richland, WA (United States)

    1996-10-01

    At present, dispersion strengthened (DS) copper is being considered as the primary candidate material for the ITER first wall and divertor components. Recently, it was agreed among the ITER parties that a backup alloy should be selected from the two well known precipitation hardened copper alloys, CuCrZr and CuNiBe. It was therefore decided to carry out screening experiments to simulate the effect of bonding and bakeout thermal cycles on microstructure, mechanical properties, and electrical resistivity of CuCrZr and CuNiBe alloys. On the basis of the results of these experiments, one of the two alloys will be selected as a backup material. Tensile specimens of CuCrZr and CuNiBe alloys were given various heat treatments corresponding to solution anneal, prime ageing, and bonding thermal cycle followed by reageing and the reactor bakeout treatment at 623K for 100 hours. Tensile specimens of the DS copper were also given the heat treatment corresponding to the bonding thermal cycle. A number of these heat treated specimens of CuCrZr, CuNiBe, and DS copper were neutron irradiated at 523K to a dose level of {approx}0.3 dpa (NRT) in the DR-3 reactor at Riso. Both unirradiated and irradiated specimens with the various heat treatments were tensile tested at 532K. The dislocation, precipitate and void microstructures and electrical resistivity of these specimens were also determined. Results of these investigations will be reported and discussed in terms of thermal and irradiation stability of precipitates and irradiation-induced precipitation and recovery of dislocation microstructure. Results show that the bonding and bakeout thermal cycles are not likely to have any serious deleterious effects on the performance of these alloys. The CuNiBe alloys were found to be susceptible to radiation-induced embrittlement, however, the exact mechanism is not yet known. It is thought that radiation-induced precipitation and segregation of the beryllium may be responsible.

  16. Pre- and post-irradiation fading effect for LiF:Mg,Ti and LiF:Mg,Cu,P materials used in routine monitoring

    International Nuclear Information System (INIS)

    Carinou, E.; Askounis, P.; Dimitropoulou, F.; Kiranos, G.; Kyrgiakou, H.; Nirgianaki, E.; Papadomarkaki, E.; Kamenopoulou, V.

    2011-01-01

    LiF is a well-known thermoluminescent (TL) material used in individual monitoring, and its fading characteristics have been studied for years. In the present study, the fading characteristics (for a period of 150 d) of various commercial LiF materials with different dopants have been evaluated. The materials used in the study are those used in routine procedures by the Personal Dosimetry Dept. of Greek Atomic Energy Commission and in particular, LiF:Mg,Ti (MTS-N, TL Poland), LiF:Mg,Cu,P (MCP-N, TL Poland), LiF:Mg,Cu,P (MCP-Ns, thin active layer detector, TL Poland) and LiF:Mg,Cu,P (TLD100H, Harshaw). The study showed that there is a sensitivity loss in signal of up to 20 % for the MTS-N material for a 150-d period in the pre-irradiation fading phase. The MCP-N has a stable behaviour in the pre-irradiation fading phase, but this also depends on the readout system. As far as the post-irradiation fading effect is concerned, a decrease of up to 20 % for the MTS-N material is observed for the same time period. On the other hand, the LiF:Mg,Cu,P material presents a stable behaviour within ±5 %. These results show that the fading effect is different for each material and should be taken into account when estimating doses from dosemeters that are in use for >2 months. (authors)

  17. Role of isolated and clustered DNA damage and the post-irradiating repair process in the effects of heavy ion beam irradiation

    International Nuclear Information System (INIS)

    Tokuyama, Yuka; Terato, Hiroaki; Furusawa, Yoshiya; Ide, Hiroshi; Yasui, Akira

    2015-01-01

    Clustered DNA damage is a specific type of DNA damage induced by ionizing radiation. Any type of ionizing radiation traverses the target DNA molecule as a beam, inducing damage along its track. Our previous study showed that clustered DNA damage yields decreased with increased linear energy transfer (LET), leading us to investigate the importance of clustered DNA damage in the biological effects of heavy ion beam radiation. In this study, we analyzed the yield of clustered base damage (comprising multiple base lesions) in cultured cells irradiated with various heavy ion beams, and investigated isolated base damage and the repair process in post-irradiation cultured cells. Chinese hamster ovary (CHO) cells were irradiated by carbon, silicon, argon and iron ion beams with LETs of 13, 55, 90 and 200 keV µm -1 , respectively. Agarose gel electrophoresis of the cells with enzymatic treatments indicated that clustered base damage yields decreased as the LET increased. The aldehyde reactive probe procedure showed that isolated base damage yields in the irradiated cells followed the same pattern. To analyze the cellular base damage process, clustered DNA damage repair was investigated using DNA repair mutant cells. DNA double-strand breaks accumulated in CHO mutant cells lacking Xrcc1 after irradiation, and the cell viability decreased. On the other hand, mouse embryonic fibroblast (Mef) cells lacking both Nth1 and Ogg1 became more resistant than the wild type Mef. Thus, clustered base damage seems to be involved in the expression of heavy ion beam biological effects via the repair process. (author)

  18. Effect of UV on the post irradiated Li Cs S O{sub 4} crystal by X and gamma radiation. Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Kassem, M E [On Leave, Alexandria University, Faculty of Science, PHysics Department. Alexandria (Egypt); EL-Kolaly, M A [On Leave, Radiation Protection Department, Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt); Al-Houty, L I [University of Qatar, Faculty of Science, Department of Physics, P.O. Box 2713, Doha (Qatar)

    1996-03-01

    Thermoluminescence characteristics of Li Cs S O{sub 4} crystal have been studied after exposure to different doses of X and Gamma-Radiations. The glow curves showed TL response of Three peaks at 75,125 and 250 degree C. The structure of the glow peaks due to X-rays is quite different from that due to gamma-rays. UV exposure yields regeneration of the TL peaks for the post irradiated samples with X or Gamma-radiation with some changes in the peaks`s structure especially the third peak. For the post X-ray irradiated crystals, the area under the third glow peak (PK III) increased with integrated time of UV exposure till about 30 min after which no changes were observed; while, for the post gamma-irradiated crystals, two linear regions were observed. The models of the TL response for the post irradiated samples as a result to UV are discussed. 5 figs.

  19. Mathematical Model for Post-Irradiation Haemopoiesis

    Energy Technology Data Exchange (ETDEWEB)

    Okunewick, J. P.; Kretchmar, A. L. [Rand Corporation, Santa Monica, CA (United States); Medical Division, Oak Ridge Associated Universities, Oak Ridge, TN (United States)

    1968-08-15

    A model for haemopoiesis has been constructed based on the following hypothesis: (a) Haemopoietic stem cells have the capability of either reproducing as stem cells or differentiating into specialized blood cells of at least two different types; (b) The size of the stem-cell compartment is in part regulated by the rate of increase due to stem-cell reproduction and in part by the rate of loss of stem cells through differentiation; (c) In addition, the size of the stem-cell compartment is in part regulated by a competitive cell-to-cell interaction between the stem-cells themselves and between the differentiating cells and the stem-cells, such that the presence of an exceptionally large number of either cell type would have a repressive effect on the rate of increase of the stem-cell population. This model has been applied to the post-irradiation erythropoietic behaviour of the rat. In the computer studies with the model, an X-ray dose sufficient to inhibit reproduction in 50% of the erythroid stem cells was assumed. It was also assumed that reproduction and differentiation are genetically separately controlled processes and that, therefore, some part of the reproductively injured cells were still capable of differentiation. Under these conditions the model predicted an abortive rise in reticulocyte number, peaking at about 6 days. True recovery was predicted to occur at about 16 days. Both the abortive rise and the true recovery were also present in those segments of the model representing earlier erythroid cells, occurring at progressively earlier times in progressively more primitive cells. Comparison of the model's predictions with experimentally obtained data for post-irradiation erythroid recovery showed a good agreement both with respect to the time of the abortive peak and the time of true recovery. (author)

  20. Mathematical Model for Post-Irradiation Haemopoiesis

    International Nuclear Information System (INIS)

    Okunewick, J.P.; Kretchmar, A.L.

    1968-01-01

    A model for haemopoiesis has been constructed based on the following hypothesis: (a) Haemopoietic stem cells have the capability of either reproducing as stem cells or differentiating into specialized blood cells of at least two different types; (b) The size of the stem-cell compartment is in part regulated by the rate of increase due to stem-cell reproduction and in part by the rate of loss of stem cells through differentiation; (c) In addition, the size of the stem-cell compartment is in part regulated by a competitive cell-to-cell interaction between the stem-cells themselves and between the differentiating cells and the stem-cells, such that the presence of an exceptionally large number of either cell type would have a repressive effect on the rate of increase of the stem-cell population. This model has been applied to the post-irradiation erythropoietic behaviour of the rat. In the computer studies with the model, an X-ray dose sufficient to inhibit reproduction in 50% of the erythroid stem cells was assumed. It was also assumed that reproduction and differentiation are genetically separately controlled processes and that, therefore, some part of the reproductively injured cells were still capable of differentiation. Under these conditions the model predicted an abortive rise in reticulocyte number, peaking at about 6 days. True recovery was predicted to occur at about 16 days. Both the abortive rise and the true recovery were also present in those segments of the model representing earlier erythroid cells, occurring at progressively earlier times in progressively more primitive cells. Comparison of the model's predictions with experimentally obtained data for post-irradiation erythroid recovery showed a good agreement both with respect to the time of the abortive peak and the time of true recovery. (author)

  1. Post irradiation examination on test fuel pins for PWR

    International Nuclear Information System (INIS)

    Fogaca Filho, N.; Ambrozio Filho, F.

    1981-01-01

    Certain aspects of irradiation technology on test fuel pins for PWR, are studied. The results of post irradiation tests, performed on test fuel pins in hot cells, are presented. The results of the tests permit an evaluation of the effects of irradiation on the fuel and cladding of the pin. (Author) [pt

  2. Post-irradiation time effects on the graft of poly(ethylene-alt-tetrafluoroethylene) (ETFE) films for ion exchange membrane application

    Energy Technology Data Exchange (ETDEWEB)

    Geraldes, Adriana N., E-mail: angeral@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Centro de Quimica e Meio Ambiente (CQMA), Av. Professor Lineu Prestes, 2242, 05508-900, Sao Paulo (Brazil); Zen, Heloisa A.; Ribeiro, Geise; Ferreira, Henrique P.; Souza, Camila P.; Parra, Duclerc F.; Santiago, Elisabete I.; Lugao, Ademar B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Centro de Quimica e Meio Ambiente (CQMA), Av. Professor Lineu Prestes, 2242, 05508-900, Sao Paulo (Brazil)

    2010-03-15

    Grafting of styrene followed by sulfonation onto poly(ethylene-alt-tetrafluoroethylene) (ETFE) was studied for synthesis of ion exchange membranes. Radiation-induced grafting of styrene onto ETFE films was investigated after simultaneous irradiation (in post-irradiation condition) using a {sup 60}Co source. The ETFE films were irradiated at 20 kGy dose at room temperature and chemical changes were monitored after contact with styrene for grafting. The post-irradiation time was established at 14 days when the films were remained in styrene/toluene 1:1 v/v. After this period the grafting degree was evaluated in the samples. The grafted films were sulfonated using chlorosulfonic acid and 1, 2-dichloroethane 20:80 (v/v) at room temperature for 5 h. The membranes were analyzed by infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), thermogravimetric measurements (TG) and degree of grafting (DOG). The ion exchange capacity (IEC) of membranes was determined by acid-base titration and the values for ETFE membranes were achieved higher than Nafion films. Preliminary single cell performance was made using pure H{sub 2} and O{sub 2} as reactants at a cell temperature of 80 deg. C and atmospheric gas pressure. The fuel cell performance of ETFE films was satisfactory when compared to state-of-art Nafion membranes.

  3. Post-irradiation time effects on the graft of poly(ethylene-alt-tetrafluoroethylene) (ETFE) films for ion exchange membrane application

    Science.gov (United States)

    Geraldes, Adriana N.; Zen, Heloísa A.; Ribeiro, Geise; Ferreira, Henrique P.; Souza, Camila P.; Parra, Duclerc F.; Santiago, Elisabete I.; Lugão, Ademar B.

    2010-03-01

    Grafting of styrene followed by sulfonation onto poly(ethylene-alt-tetrafluoroethylene) (ETFE) was studied for synthesis of ion exchange membranes. Radiation-induced grafting of styrene onto ETFE films was investigated after simultaneous irradiation (in post-irradiation condition) using a 60Co source. The ETFE films were irradiated at 20 kGy dose at room temperature and chemical changes were monitored after contact with styrene for grafting. The post-irradiation time was established at 14 days when the films were remained in styrene/toluene 1:1 v/v. After this period the grafting degree was evaluated in the samples. The grafted films were sulfonated using chlorosulfonic acid and 1, 2-dichloroethane 20:80 (v/v) at room temperature for 5 h. The membranes were analyzed by infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), thermogravimetric measurements (TG) and degree of grafting (DOG). The ion exchange capacity (IEC) of membranes was determined by acid-base titration and the values for ETFE membranes were achieved higher than Nafion ® films. Preliminary single cell performance was made using pure H 2 and O 2 as reactants at a cell temperature of 80 °C and atmospheric gas pressure. The fuel cell performance of ETFE films was satisfactory when compared to state-of-art Nafion ® membranes.

  4. Investigation of the effect of temperature, dose rate and short-term post-irradiation change on the response of various types of dosimeters to cobalt-60 gamma radiation for quality assurance in Thailand

    International Nuclear Information System (INIS)

    Biramontri, S.

    2000-01-01

    The influences of combined effect of irradiation temperature from -80 deg. C to 60 deg. C and dose rate between 0.2 and 4 Gy/s on the gamma ray response of several commercial routine dosimeters (Harwell Red 4034, Gammachrome YR, FWT-60-00 radiochromic films, FWT-70-40 optical waveguides, GafChromic films, and Fuji CTA-FTR-125 films) were investigated for quality assurance in radiation processes. Besides, the studies of short term post-irradiation stability for the period of 2 h to 7 days are also presented. The overall results indicate the need for a calibration protocol under conditions of use. (author)

  5. New Therapeutic Possibilities of the Post-Irradiation Haemorrhagic Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Pospisil, J.; Dienstbier, Z. [Institute of Biophysics and Nuclear Medicine, Faculty of General Medicine, Charles University, Prague, Czechoslovak Socialist Republic (Czech Republic); Skala, E. [Central Military Hospital, Prague-Stresovice, Czechoslovak Socialist Republic (Czech Republic)

    1969-10-15

    Haemorrhagic diathesis is one of the dominant symptoms of acute post-irradiation lesion. Haemorrhagic syndrome is caused by the disturbance of haemocoagulation during simultaneous lesion of the vascular system. In our study we have tried to affect the post-irradiation haemocoagulation disturbance. Epsilon- amino-caproic acid (EACA) administered between the 8{sup th} and the 18{sup th} day (0.4 g/kg per day) to whole- body irradiated dogs (600 R) partially regulated the post-irradiation disturbance of haemocoagulation. The favourable effect of EACA was verified by in vitro experiments in which the blood of irradiated dogs was used. A repeated administration of EACA in the dose of 0.4 g/kg per day to whole-body irradiated rats (600 R) did not substantially affect the post-irradiation changes in the number of white blood elements; however, its administration to healthy animals caused lymphocytosis. In whole-body irradiated dogs (600 R) we have found lower levels of EACA in the blood up to the 8 day following irradiation as compared with healthy dogs after oral application of EACA. The whole-body irradiation of mice did not increase the acute toxicity of EACA. The daily administration of 0.4 g EACA/kg to whole-body irradiated mice (600 and 700 R) did not change the mortality induced by irradiation. The authors consider EACA to be a suitable compound for a complex therapy of radiation sickness. The administration of para-amino-methyl-benzoic acid (PAMBA), in spite of a certain improvement of postirradiation haemocoagulation disturbance, is less efficient. Our recent experiments with ellagic acid which significantly affects the post-traumatic haemorrhage in whole-body irradiated rats seem to be very promising. (author)

  6. Post-irradiation stability of polyvinyl chloride at sterilizing doses

    International Nuclear Information System (INIS)

    Naimian, F.; Katbab, A.A.; Nazokdast, H.

    1994-01-01

    Post-irradiation stability of plasticized PVC irradiated by 60 Co gamma ray at sterilizing doses has been studied. Effects of irradiation upon chemical structure, mechanical properties and rheological behaviour of samples contained different amounts of Di(2-ethylhexyl)phthalate as plasticizer have been investigated. Formation of conjugated double bonds, carbonyl and hydroxyl groups have been followed by UV and FTIR spectrometers up to 6 months after irradiation. FTIR spectra of irradiated samples showed no significant changes in carbonyl and hydroxyl groups even 6 months after irradiation. However, changes in UV-visible spectra was observed for the irradiated samples up to 6 months post-irradiation. This has been attributed to the formation of polyenes which leads to the discoloration of this polymer. Despite a certain degree of discoloration, it appears that the mechanical properties of PVC are not affected by irradiation at sterilizing doses. No change in the melt viscosity of the irradiated PVC samples with post-irradiation was observed, which is inconsistent with the IR results. (author)

  7. Hot cell facilities for post irradiation examination

    International Nuclear Information System (INIS)

    Mishra, Prerna; Bhandekar, Anil; Pandit, K.M.; Dhotre, M.P.; Rath, B.N.; Nagaraju, P.; Dubey, J.S.; Mallik, G.K.; Singh, J.L.

    2017-01-01

    Reliable performance of nuclear fuels and critical core components has a large bearing on the economics of nuclear power and radiation safety of plant operating personnel. In view of this, Post Irradiation Examination (PIE) is periodically carried out on fuels and components to generate feedback information which is used by the designers, fabricators and the reactor operators to bring about changes for improved performance of the fuel and components. Examination of the fuel bundles has to be carried out inside hot cells due to their high radioactivity

  8. Post irradiation examinations cooperation and worldwide utilization of facilities

    International Nuclear Information System (INIS)

    Karlsson, Mikael

    2009-01-01

    Status of post irradiation examinations in Studsvik's facilities, cooperation and worldwide utilization of facilities, was described. Studsvik cooperate with irradiation facilities, as Halden, CEA and JAEA, as well as other hot cell facilities (examples, PSI, ITU and NFD) universities (example, the Royal Institute of Technology in Sweden) in order to be able to provide everything asked for by the nuclear community. Worldwide cooperation for effective use of expensive and highly specialized facilities is important, and the necessity of cooperation will be more and more recognized in the future. (author)

  9. Heat-treated mineral-yeast as a potent post-irradiation radioprotector

    International Nuclear Information System (INIS)

    Anzai, Kazunori; Ueno, Megumi; Nyui, Minako; Ikota, Nobuo; Kagiya, Tsutomu V.

    2008-01-01

    In vivo radioprotection of C3H mice by i.p. administration of Zn-, Mn-, Cu-, or Se-containing heat-treated Saccharomyces serevisiae yeast sample was examined. The 30-day survival of the group treated 30 min before 7.5 Gy whole-body X-irradiation with mineral-containing yeast powders suspended in 0.5% methylcellulose was significantly higher than that of control group. When mineral-yeast was administered immediately after irradiation, the survival rate was even higher and Zn- or Cu-yeast showed the highest rate (more than 90%). Although treatment with simple yeast showed a high survival rate (73%), it was significantly lower than that obtained by the Zn-yeast treatment. The effects of Zn-yeast were studied further. When the interval between irradiation and administration was varied, the protective activity of Zn-yeast decreased gradually by increasing the interval but was still significantly high for the administration at 10 h post-irradiation. The dose reduction factor of Zn-yeast (100 mg/kg, i.p. administration immediately after irradiation) was about 1.2. When the suspension of Zn-yeast was fractionated by centrifugation, the insoluble fraction showed a potent effect, while the soluble fraction had only a moderate effect. In conclusion, mineral-yeast, especially Zn-yeast, provides remarkable post-irradiation protection against lethal whole body X-irradiation. The activity is mainly attributable to the insoluble fraction, whereas some soluble components might contribute to the additional protective activity. (author)

  10. AGC-2 Specimen Post Irradiation Data Package Report

    Energy Technology Data Exchange (ETDEWEB)

    Windes, William Enoch [Idaho National Lab. (INL), Idaho Falls, ID (United States); Swank, W. David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rohrbaugh, David T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cottle, David L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-08-01

    This report documents results of the post-irradiation examination material property testing of the creep, control, and piggyback specimens from the irradiation creep capsule Advanced Graphite Creep (AGC)-2 are reported. This is the second of a series of six irradiation test trains planned as part of the AGC experiment to fully characterize the neutron irradiation effects and radiation creep behavior of current nuclear graphite grades. The AGC-2 capsule was irradiated in the Idaho National Laboratory Advanced Test Reactor at a nominal temperature of 600°C and to a peak dose of 5 dpa (displacements per atom). One-half of the creep specimens were subjected to mechanical stresses (an applied stress of either 13.8, 17.2, or 20.7 MPa) to induce irradiation creep. All post-irradiation testing and measurement results are reported with the exception of the irradiation mechanical strength testing, which is the last destructive testing stage of the irradiation testing program. Material property tests were conducted on specimens from 15 nuclear graphite grades using a similar loading configuration as the first AGC capsule (AGC-1) to provide easy comparison between the two capsules. However, AGC-2 contained an increased number of specimens (i.e., 487 total specimens irradiated) and replaced specimens of the minor grade 2020 with the newer grade 2114. The data reported include specimen dimensions for both stressed and unstressed specimens to establish the irradiation creep rates, mass and volume data necessary to derive density, elastic constants (Young’s modulus, shear modulus, and Poisson’s ratio) from ultrasonic time-of-flight velocity measurements, Young’s modulus from the fundamental frequency of vibration, electrical resistivity, and thermal diffusivity and thermal expansion data from 100–500°C. No data outliers were determined after all measurements were completed. A brief statistical analysis was performed on the irradiated data and a limited comparison between

  11. VVER fuel. Results of post irradiation examination

    International Nuclear Information System (INIS)

    Smirnov, V.P.; Markov, D.V.; Smirnov, A.V.; Polenok, V.S.; Perepelkin, S.O.; Ivashchenko, A.A.

    2005-01-01

    The present paper presents the main results of post-irradiation examination of more than 40 different fuel assemblies (FA) operated in the cores of VVER-1000 and VVER-440-type power reactors in a wide range of fuel burnup. The condition of fuel assembly components from the viewpoint of deformation, corrosion resistance and mechanical properties is described here. A serviceability of the FA design as a whole and interaction between individual FA components under vibration condition and mechanical load received primary emphasis. The reasons of FA damage fuel element failure in a wide range of fuel burnup are also analyzed. A possibility and ways of fuel burnup increase have been proved experimentally for the case of high-level serviceability maintenance of fuel elements to provide for advanced fuel cycles. (author)

  12. Cytogenetics of Post-Irradiation Mouse Leukaemia

    Energy Technology Data Exchange (ETDEWEB)

    Wald, N.; Pan, S.; Upton, A.; Brown, R. [Graduate School of Public Health, University of Pittsburgh, PA (United States); Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1969-11-15

    The interrelationship between radiation, cytogenetic abnormalities, and viruses in leukaemogenesis has been studied in the RF/Un mouse which develops a high incidence of granulocytic leukaemia on radiation exposure. A virus-like agent has been demonstrated in such leukaemic animals and the disease has been transmitted by passage of apparently acellular materials from irradiated primary animals to normal recipients. Pilot cytogenetic studies revealed consistent abnormal chromosome markers and modal shifts in both irradiated leukaemic animals and in non-irradiated animals developing leukaemia after passage injection. To define better the relationship between consistent bone-marrow chromosome aberrations and postirradiation primary and passaged leukaemia, 100 RF/Un mice were studied which were irradiated with 300 R of 250-kVp X-rays at 100 weeks of age and subsequently developed leukaemia. Eighty-seven had granulocytic leukaemia and in 72 of these, bone-marrow cytogenetic abnormalities were found. The distribution of-numerical and structural chromosome aberrations in 3225 cells studied are reviewed in derail. The correlation of specific aberrations to clinical and histopathologic findings has been attempted: Sequential passages of apparently cell-free material from the post-irradiation leukaemic mice into unirradiated RE/Un recipients and subsequent passages from leukaemic recipients were performed to observe the evolution of any initial chromosome markers and shifts in modal chromosome number in the passage generations. Two-hundred-thirty-six mice were inoculated with the material obtained either from primary post-irradiation leukaemic mice or from serially-passaged leukaemia cases. In the most extensive passaged line, 22 transfer generations containing 129 leukaemic mice were examined by clinical, histopathologic, -haematologic and cytogenetic procedures. Evolution of abnormal chromosome modes from 41 in the early passages to 39 chromosomes consistently after the 4

  13. Influence of thiamine on the post-irradiation effect caused by fast neutrons or gamma radiation in callus cultures of Haplopappus gracilis (Nutt) A. Gray

    International Nuclear Information System (INIS)

    Wajda, L.; Korzonek, M.

    1979-01-01

    Influence of thiamine within the investigated range of concentrations 1.5 to 12.0 mg/l on the postirradiation effect caused by fast neutrons or gamma irradiation was found in cultures of Haplopappus gracilis callus. The lowest sensitivity to fast neutrons was noticed in callus grown on nutrient combination 1.5 to 3.0 and 12.0 to 3.0 mg/l of thiamine. On the contrary the highest sensitivity to gamma radiation was shown by cultures grown on nutrient media: 1.5 to 3.0 mg/l; all the other investigated thiamine concentrations caused a marked decrease in the sensitivity of the callus. (author)

  14. Operation of post-irradiation examination facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E. G.; Jeon, Y. B.; Ku, D. S.

    1996-12-01

    In 1996, the post-irradiation examination(PIE) of nuclear fuels was performed as follows. It has been searched for the caution of defection of defected fuel rods of Youngkwang-4 reactor through NDT and metallographic examination that had been required by KEPCO. And in-pool inspection of Kori-1 spent fuel assembly(FO2) was carried out. HVAC system and pool water treatment system have been operated to maintain the facility safely, and electric power supply system was checked and maintained for the normal and steady supply electric power to the facility. Image processing software was developed for measurement of defection of spent fuel rods. Besides, a radiation shielding glove box was fabricated and a hot cell compressor for volume reduction of radioactive materials was fabricated and installed in hot cell. Safeguards of nuclear materials were implemented in strict accordance with the relevant Korean rules and regulations as well as the international non-proliferation regime. Also the IAEA inspection was carried out on the quarterly basis. (author). 31 tabs., 71 figs., 4 refs.

  15. Post-irradiation annealing of coarse-grained model alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ray, P H.N.; Wilson, C; McElroy, R J [AEA Reactor Services, Harwell (United Kingdom)

    1994-12-31

    Thermal ageing and irradiation studies have been carried out on three model alloys (JPC, JPB, JPG) that have identical compositions except for different levels of phosphorus and/or copper. They have been irradiated in three conditions, as-received, heat treated to produce a coarse grained microstructure (similar to heat-affected-zone), and in this condition further aged at 450 C to produce a temper embrittled condition. One of the alloy have been subject to a post-irradiation anneal. The effect of these treatments on mechanical property changes has been characterized by Charpy testing and Vickers hardness measurements; the phosphorus segregation has been studied by a combination of STEM and Auger techniques.

  16. Operation of post-irradiation examination facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ka; Park, Kwang Joon; Jeon, Yong Bum [and others; Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-02-01

    In 1995, the post-irradiation examination (PIE) of nuclear fuels was performed as follows. The relation between burnup and top nozzle spring force of fuel assembly was obtained by measuring the holddown spring force on the Kori-1 reactor fuel assemblies. The resonance ultrasonic test for inspection of defect and moisture in fuel rod was carried out on fuel rods of C15 and J14 assemblies, and the change of fuel rod condition by storing in pool has been analyzed on the intentionally defected fuel rods (ID-C and ID-L) as well as intact fuel rod (1-2) by NDT in ht cell. The oxide layer thickness on cladding surface of J44-L12 fuel rod was measured by NDT method and metallography to reveal the oxidation as a function of temperature in the fuel rod, and the burnup of J44 fuel assembly was measured by chemical analysis. HVAC system and pool water treatment system of the PIE facility were continuously operated for air filtration and water purification. The monitoring of radiation and pool water in PIE facility has been carried out to maintain the facility safety, and electric power supply system was checked and maintained to supply the electric power to the facility normally. The developed measurement techniques of oxide layer thickness on fuel rod cladding and holddown spring force of top nozzle in fuel assembly were applied to examine the nuclear fuels. Besides, a radiation shielding glove box was designed and a hot cell compressor for volume reduction of radioactive materials was fabricated. 19 tabs., 38 figs., 7 refs. (Author) .new.

  17. Hair transplantation for the the treatment of post-irradiation alopecia

    International Nuclear Information System (INIS)

    Kolasinski, J.; Kolenda, M.; Skowronek, J.

    2002-01-01

    Treatment of head and neck tumours and of leukaemia often necessitates radiotherapy. However; permanent alopecia in the scalp exposed to irradiation is a common problem. One of the effective methods of treatment of post-irradiation alopecia is hair transplantation. Over a period of 18 years 42 patients were treated at the Hair Clinic Poznan for post-irradiation alopecia. Due to the presence of numerous lesions in the donor and recipient scalp areas many modifications were introduced into alopecia correction. The treatment assured good cosmetic effects, free of the risk of complications. Scalps from occipital areas do not go bald when transferred to scalp areas affected by balding. On the contrary - they retain original properties, thus resulting in hair re-growth. Hair follicle transplantation is usually applied for the correction of androgenic alopecia in men and women although it may also be applied in post-trauma and post-irradiation alopecia treatment. Hair regrowth in radiotherapy patients occurs later than in androgenic alopecia patients. This phenomenon is caused by blood supply deficits in the recipient area. Autogenic hair follicle transplantation is a treatment of choice in the correction of post-irradiation alopecia, while the good cosmetic effects considerably improve the patients' quality of life. (author)

  18. IAEA Post Irradiation Examination Facilities Database

    International Nuclear Information System (INIS)

    Jenssen, Haakon; Blanc, J.Y.; Dobuisson, P.; Manzel, R.; Egorov, A.A.; Golovanov, V.; Souslov, D.

    2005-01-01

    The number of hot cells in the world in which post irradiation examination (PIE) can be performed has diminished during the last few decades. This creates problems for countries that have nuclear power plants and require PIE for surveillance, safety and fuel development. With this in mind, the IAEA initiated the issue of a catalogue within the framework of a coordinated research program (CRP), started in 1992 and completed in 1995, under the title of ''Examination and Documentation Methodology for Water Reactor Fuel (ED-WARF-II)''. Within this program, a group of technical consultants prepared a questionnaire to be completed by relevant laboratories. From these questionnaires a catalogue was assembled. The catalogue lists the laboratories and PIE possibilities worldwide in order to make it more convenient to arrange and perform contractual PIE within hot cells on water reactor fuels and core components, e.g. structural and absorber materials. This catalogue was published as working material in the Agency in 1996. During 2002 and 2003, the catalogue was converted to a database and updated through questionnaires to the laboratories in the Member States of the Agency. This activity was recommended by the IAEA Technical Working Group on Water Reactor Fuel Performance and Technology (TWGFPT) at its plenary meeting in April 2001. The database consists of five main areas about PIE facilities: acceptance criteria for irradiated components; cell characteristics; PIE techniques; refabrication/instrumentation capabilities; and storage and conditioning capabilities. The content of the database represents the status of the listed laboratories as of 2003. With the database utilizing a uniform format for all laboratories and details of technique, it is hoped that the IAEA Member States will be able to use this catalogue to select laboratories most relevant to their particular needs. The database can also be used to compare the PIE capabilities worldwide with current and future

  19. WWER fuel: Results of post irradiation examination

    International Nuclear Information System (INIS)

    Markov, D.V.; Smirnov, V.P.; Smirnov, A.V.; Polenok, V.S.; Perepelkin, S.O.; Ivashchenko, A.A.

    2006-01-01

    Experience in the field of fabrication, operation, testing and post-irradiation examinations (PIE) made it possible to settle the following requirements for a new generation of WWER nuclear fuel: - For WWER-1000 FA, the service life is no less than 5 years, 3 alternative fuel cycles (FC): 12 months x 4 FCs, 12 months x 5 FCs and 18 months x 3 FCs; - For WWER-440 FA, fuel cycle is 12 months x 5 FCs and a part of operating assembly is left for the 6. year; - High fuel burnup - up to 70 MWd/kgU; - Dimensional stability of FA and its components; - FA repairability; - Adaptability of fuel cycles; - Maintenance of maneuvering operating conditions at the NPP; - Reliability of control rod operation; - High serviceability level - FE leakage is no worse than 10-5 l/year. In order to provide the fulfillment of the above-given requirements, designers and production engineers have worked out cumulative measures and engineering solutions, which are introduced in development of a new generation fuel. Currently old design FA-M assemblies provided with steel skeleton are being operated in WWER-1000 reactors at Ukrainian and Bulgarian NPPs. As for Russian NPPs, new-type FAs are operated. These are advanced FAs (AFA), FA-A and FA-2 provided with zirconium alloy skeletons. A design of the second generation of WWER-440 operating assemblies was developed with respect to changes in some geometrical parameters, fastening of FEs in the lower grid (splinting was substituted for collet), usage of reinforcing rib under the lower grid, anti-debris filter and hafnium elements of junction unit as well as hafnium content decrease from 0.05 % mass down to 0.01% mass in zirconium materials. They are basic designs of FAs in order to be introduced in a five-year fuel cycle of WWER-440 NPPs in Czech Republic and Slovakia since 2005 and have got prospects for development. The operating experience of dismountable operating assemblies at the Loviisa NPP, vibration-proof operating assemblies at the

  20. Post-irradiation modification of oxygen-dependent and independent damage by catalase in barley seeds

    International Nuclear Information System (INIS)

    Sah, N.K.; Kesavan, P.C.

    1987-01-01

    If H 2 O 2 is one of the major mediators of the 'oxygen effect' in biological systems then catalase, which enzymically decomposes H 2 O 2 should have a significant influence on radiation damage, particularly under oxygenated conditions. The post-irradiation (300 Gy gamma rays) effect of catalase was, therefore, assessed on barley seeds of about 4% moisture content under oxygenated and oxygen-free conditions at varying temperatures. Catalase affords concentration-dependent radioprotection under oxygenated condition at both 25 0 C and 4 0 C. The level of protection at 4 0 C is less than at 25 0 C. This is obviously due to a decrease in catalase activity at low temperature. Under oxygen-free conditions, catalase enhances radiation damage at 4 0 C while at 25 0 C it it has no effect. This has been substantiated by data on the frequency of chromosomal aberrations and on peroxidase activity. Sodium azide, a catalase inhibitor, was found to eliminate the radioprotective action of catalase. The study supports the view that the 'oxygen effect' is mediated largely through peroxides in irradiated biological systems. However, the observations made particularly at 4 0 C under oxygen-free condition seem to involve physicochemical reactions. (author)

  1. Post Irradiation Capabilities at the Idaho National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Schulthess, J.L.

    2011-08-01

    The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) oversees the research, development, and demonstration activities that ensure nuclear energy remains a viable energy option for the United States. Fuel and material development through fabrication, irradiation, and characterization play a significant role in accomplishing the research needed to support nuclear energy. All fuel and material development requires the understanding of irradiation effects on the fuel performance and relies on irradiation experiments ranging from tests aimed at targeted scientific questions to integral effects under representative and prototypic conditions. The DOE recently emphasized a solution-driven, goal-oriented, science-based approach to nuclear energy development. Nuclear power systems and materials were initially developed during the latter half of the 20th century and greatly facilitated by the United States ability and willingness to conduct large-scale experiments. Fifty-two research and test reactors with associated facilities for performing fabrication and pre and post irradiation examinations were constructed at what is now Idaho National Laboratory (INL), another 14 at Oak Ridge National Laboratory (ORNL), and a few more at other national laboratory sites. Building on the scientific advances of the last several decades, our understanding of fundamental nuclear science, improvements in computational platforms, and other tools now enable technological advancements with less reliance on large-scale experimentation.

  2. Post Irradiation Capabilities at the Idaho National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Schulthess, J.L.; Robert D. Mariani; Rory Kennedy; Doug Toomer

    2011-08-01

    The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) oversees the research, development, and demonstration activities that ensure nuclear energy remains a viable energy option for the United States. Fuel and material development through fabrication, irradiation, and characterization play a significant role in accomplishing the research needed to support nuclear energy. All fuel and material development requires the understanding of irradiation effects on the fuel performance and relies on irradiation experiments ranging from tests aimed at targeted scientific questions to integral effects under representative and prototypic conditions. The DOE recently emphasized a solution-driven, goal-oriented, science-based approach to nuclear energy development. Nuclear power systems and materials were initially developed during the latter half of the 20th century and greatly facilitated by the United States’ ability and willingness to conduct large-scale experiments. Fifty-two research and test reactors with associated facilities for performing fabrication and pre and post irradiation examinations were constructed at what is now Idaho National Laboratory (INL), another 14 at Oak Ridge National Laboratory (ORNL), and a few more at other national laboratory sites. Building on the scientific advances of the last several decades, our understanding of fundamental nuclear science, improvements in computational platforms, and other tools now enable technological advancements with less reliance on large-scale experimentation.

  3. Post irradiation test report of irradiated DUPIC simulated fuel

    International Nuclear Information System (INIS)

    Yang, Myung Seung; Jung, I. H.; Moon, J. S. and others

    2001-12-01

    The post-irradiation examination of irradiated DUPIC (Direct Use of Spent PWR Fuel in CANDU Reactors) simulated fuel in HANARO was performed at IMEF (Irradiated Material Examination Facility) in KAERI during 6 months from October 1999 to March 2000. The objectives of this post-irradiation test are i) the integrity of the capsule to be used for DUPIC fuel, ii) ensuring the irradiation requirements of DUPIC fuel at HANARO, iii) performance verification in-core behavior at HANARO of DUPIC simulated fuel, iv) establishing and improvement the data base for DUPIC fuel performance verification codes, and v) establishing the irradiation procedure in HANARO for DUPIC fuel. The post-irradiation examination performed are γ-scanning, profilometry, density, hardness, observation the microstructure and fission product distribution by optical microscope and electron probe microanalyser (EPMA)

  4. Post-irradiation data analysis for NRC/PNL Halden assembly IFA-431

    International Nuclear Information System (INIS)

    Nealley, C.; Lanning, D.D.; Cunningham, M.E.; Hann, C.R.

    1979-10-01

    Results are presented for the post irradiation examination performed on IFA-431, which was a 6-rod test fuel assembly irradiated in Halden Reactor, Norway, under sponsorship of the Nuclear Regulatory Commission. The irradiation conditions included: peak powers of 33 kW/m; coolant pressure and temperature of 3.3 MPa and 240 0 C, respectively; and peak burnup of 4300 MWd/MTM. IFA-431 included instrumented rods of basic boiling water reactor design, with variations in fill gas composition, gap size, and UO 2 fuel type. The irradiation was designed to measure the effect of these variations upon fuel rod thermal and mechanical performance. The post irradiation examination assessed the permanent changes to the rods, including induced radioactivity, cladding deformation, fission gas release, and fuel densification

  5. Polyamines and post-irradiation cell proliferation

    International Nuclear Information System (INIS)

    Rosiek, O.; Wronowski, T.; Lerozak, K.; Kopec, M.

    1978-01-01

    The results of three sets of experiments will be presented. Firstly polyamines and DNA content was determined in bone marrow, mesenteric lymph nodes, spleen, liver and kidney of rabbits at the 1, 5, 10 and 20th day after exposure to 600 R of X-irradiation. Polyamine concentration in bone marrow, spleen and lymph nodes was found to be markedly increased during the period of postirradiation recovery. Secondly, effect of 10 -5 M methyl glyoxalbis, guanylhydrazone (MGBG), an inhibitor of spermidine and spermine synthesis, on multiplication of X-irradiated cultures of murine lymphoblaste L5178Y-S was assessed. MGBG-induced inhibition of cell proliferation could be prevented by concurrent administration of 10 -4 M spermidine. Thirdly the influence of putrescine on bone marrow cellularity and 3 H-thymidine incorporation into bone marrow cells was investigated in X-irradiated mice. The results obtained indicate close relation of polyamines to cell proliferation processes after irradiation. (orig./AJ) [de

  6. Post-irradiation chemical analyses of poultry

    International Nuclear Information System (INIS)

    Singh, H.

    1988-01-01

    Salmonella contamination of chicken is a major public health concern, causing sickness and loss of productivity. Modern concentrated production methods increase the difficulty of Salmonella control. While heat pasteurization and chlorine treatment for Salmonella have shortcomings, low doses of gamma radiation are very effective in controlling Salmonella and spoilage microorganisms. The organoleptic shelf life of fresh chicken at 1 to 4 degrees Celsius (6 to 10 days) is extended by a factor of ∼ 2 by a dose of 2.5 kGy and does not increase further with higher doses up to ∼ 8 kGy. The reason for the lack of greater organoleptic shelf life by more than a factor of ∼ 2 is the continuing degradative changes in meat due to enzymatic activity. The product obtained with doses around 2.5 kGy is very good, and is acceptable up to doses of ∼ 8 kGy. Irradiation at doses higher than 2.5 kGy results in some radiation odor that disappears on storage at 1 to 4 degrees Celsius, and on roasting of the meat. The odor is due to the production of some of the small molecular weight volatile compounds, which are also produced by free-radical mediated autoxidation, thermal treatment, and enzymatic and microbial reactions with the meat components. Low-dose irradiation shows insignificant changes in the physical attributes like water-holding capacity, changes in proteins, amino acids, fats and rancidity indices. Review of the feeding studies with radiation-sterilized chicken meat (≥ 30 kGy, the Raltech study) indicated that the irradiated meat was wholesome and safe. It is therefore, reasonable to assume that the low-dose (≤ 8 kGy) irradiated chicken would also be safe. Also the two Federation of American Societies for Experimental Biology (FASEB) committees, which reviewed the over 100 identified volatile compounds produced in μg/kg (ppb) quantities, concluded that there were no ground for suspecting these products of being a hazard to the consumer

  7. Advanced Post-Irradiation Examination Capabilities Alternatives Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Jeff Bryan; Bill Landman; Porter Hill

    2012-12-01

    An alternatives analysis was performed for the Advanced Post-Irradiation Capabilities (APIEC) project in accordance with the U.S. Department of Energy (DOE) Order DOE O 413.3B, “Program and Project Management for the Acquisition of Capital Assets”. The Alternatives Analysis considered six major alternatives: ? No Action ? Modify Existing DOE Facilities – capabilities distributed among multiple locations ? Modify Existing DOE Facilities – capabilities consolidated at a few locations ? Construct New Facility ? Commercial Partnership ? International Partnerships Based on the alternatives analysis documented herein, it is recommended to DOE that the advanced post-irradiation examination capabilities be provided by a new facility constructed at the Materials and Fuels Complex at the Idaho National Laboratory.

  8. RERTR-12 Post-irradiation Examination Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Rice, Francine [Idaho National Lab. (INL), Idaho Falls, ID (United States); Williams, Walter [Idaho National Lab. (INL), Idaho Falls, ID (United States); Robinson, Adam [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States); Meyer, Mitch [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rabin, Barry [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-02-01

    The following report contains the results and conclusions for the post irradiation examinations performed on RERTR-12 Insertion 2 experiment plates. These exams include eddy-current testing to measure oxide growth; neutron radiography for evaluating the condition of the fuel prior to sectioning and determination of fuel relocation and geometry changes; gamma scanning to provide relative measurements for burnup and indication of fuel- and fission-product relocation; profilometry to measure dimensional changes of the fuel plate; analytical chemistry to benchmark the physics burnup calculations; metallography to examine the microstructural changes in the fuel, interlayer and cladding; and microhardness testing to determine the material-property changes of the fuel and cladding.

  9. Mitigating IASCC of Reactor Core Internals by Post-Irradiation Annealing

    Energy Technology Data Exchange (ETDEWEB)

    Was, Gary [Univ. of Michigan, Ann Arbor, MI (United States)

    2017-06-02

    This final report summarizes research performed during the period between September 2012 and December 2016, with the objective of establishing the effectiveness of post-irradiation annealing (PIA) as an advanced mitigation strategy for irradiation-assisted stress corrosion cracking (IASCC). This was completed by using irradiated 304SS control blade material to conduct crack initiation and crack growth rate (CGR) experiments in simulated BWR environment. The mechanism by which PIA affects IASCC susceptibility will also be verified. The success of this project will provide a foundation for the use of PIA as a mitigation strategy for core internal components in commercial reactors.

  10. Mitigating IASCC of Reactor Core Internals by Post-Irradiation Annealing

    International Nuclear Information System (INIS)

    Was, Gary

    2017-01-01

    This final report summarizes research performed during the period between September 2012 and December 2016, with the objective of establishing the effectiveness of post-irradiation annealing (PIA) as an advanced mitigation strategy for irradiation-assisted stress corrosion cracking (IASCC). This was completed by using irradiated 304SS control blade material to conduct crack initiation and crack growth rate (CGR) experiments in simulated BWR environment. The mechanism by which PIA affects IASCC susceptibility will also be verified. The success of this project will provide a foundation for the use of PIA as a mitigation strategy for core internal components in commercial reactors.

  11. New radiation mitigators to reduce bone marrow death of mice by post-irradiation administration

    International Nuclear Information System (INIS)

    Anzai, Kazunori

    2009-01-01

    We have found recently that heat-treated mineral yeast preparations and water-soluble analogs of vitamin E are potent radiation mitigator to reduce bone marrow death of mice by post-irradiation administration. When administered immediately after whole-body X-irradiation (7.5 Gy), both Zn-yeast and γ-tocopherol dimethylglycine ester (TDMG) significantly increased the viability of mice from 0% (control) to more than 90% (treated). Zn-yeast did not inhibit the tumor-regulation by γ-rays but even sensitize the radiation effect in mice xenografts of HeLa cells. (author)

  12. Post Irradiation Mechanical Behaviour of Three EUROFER Joints

    International Nuclear Information System (INIS)

    Lucon, E.; Leenaers, A.; Vandermeulen, W.

    2006-01-01

    The post-irradiation mechanical properties of three EUROFER joints (two diffusion joints and one TIG weld) have been characterized after irradiation to 1.8 dpa at 300 degrees Celsius in the BR-2 reactor. Tensile, KLST impact and fracture toughness tests have been performed. Based on the results obtained and on the comparison with data from EUROFER base material irradiated under similar conditions, the post-irradiation mechanical behaviour of both diffusion joints (laboratory and mock-up) appears similar to that of the base material. The properties of the TIG joint are affected by the lack of a post-weld heat treatment, which causes the material from the upper part of the weld to be significantly worse than that of the lower region. Thus, specimens from the upper layer exhibit extremely pronounced hardening and embrittlement caused by irradiation. The samples extracted from the lower layer show much better resistance to neutron exposure, although their measured properties do not match those of the diffusion joints. The results presented demonstrate that diffusion joining can be a very promising technique.

  13. Proteomics of post-irradiation recovery in D. radiodurans

    International Nuclear Information System (INIS)

    Basu, Bhakti; Apte, Shree Kumar

    2012-01-01

    An extremophile Deinococcus radiodurans is bestowed with an extraordinary DNA repair ability that renders it virtually resistant to all known forms of DNA damage caused by ionizing radiations (10 kGy of gamma rays), UV (1 kJ/m 2 ) or weeks of desiccation etc. The genome of D. radiodurans encodes a unique combination of DNA repair pathways such as prokaryotic type RecFOR mediated homologous recombination (HR) and nucleotide/base excision repair along with eukaryotic type strand annealing (SA) and non-homologous end joining (NHEJ), but is devoid of universal prokaryotic DNA repair pathways such as RecBCD mediated HR, photo-reactivation and SOS response. Collective evidence obtained so far from multiple approaches, have indicated (i) that all genes essential for DNA repair are not necessarily induced following radiation stress (ii) early RecA independent DNA assembly occurs, and (iii) absolute necessity of RecA dependent HR for final genome restitution. The 6 kGy gamma irradiation inducible proteome dynamics were mapped during the post-irradiation growth arrest phase by 2D protein electrophoresis coupled with mass spectrometry. Radiation inducible expression of at least 33 proteins was evident in the first 1h of post irradiation recovery

  14. Nondestructive post-irradiation examination of Loop-1, S1 and B1 rods

    International Nuclear Information System (INIS)

    Bratton, R.L.

    1997-05-01

    As a part of the Pacific Northwest National Laboratory's Tritium Target Development Program, eleven tritium target rods were irradiated in the Advanced Test Reactor located at the Idaho National Engineering and Environmental Laboratory during 1991. Both nondestructive and destructive post-irradiation examination on all eleven rods was planned under the Tritium Target Development Program. Funding for the program was reduced in 1991 resulting in the early removal of the program experiments before reaching their irradiation goals. Post-irradiation examination was only performed on one of the irradiated rods at the Pacific Northwest National Laboratory before the program was terminated in 1992. On December 6, 1995, the Secretary of Energy announced the pursuit of the Commercial Light-Water Reactor option for producing tritium establishing the Tritium Target Qualification Program at the Pacific Northwest National Laboratory. This program decided to pursue nondestructive and destructive post-irradiation examination of the ten remaining rods from the previous program. The ten rods comprise three experiments. The Loop-1 experiment irradiated eight target rods in a loop configuration for 217 irradiation days. The other two rods were irradiated in two separate irradiation experiments, designated as S1 and B1 for 143 effective full-power days, but at different power levels. After the ten rods were transferred from the ATR Canal to the Hot Fuels Examination Facility, the following examinations were performed: (1) visual examination and photography; (2) neutron radiography; (3) axial gamma scanning; (4) contact profilometry measurement; (5) bow and length measurements; (6) rod puncture and plenum gas analysis/measurement of plenum gas quantity; (7) void volume determination; and (8) internal pressure determination. This report presents the data collected during these examinations

  15. The growth of intra-granular bubbles in post-irradiation annealed UO2 fuel

    International Nuclear Information System (INIS)

    White, R.J.

    2001-01-01

    Post-irradiation examinations of low temperature irradiated UO 2 reveal large numbers of very small intra-granular bubbles, typically of around 1 nm diameter. During high temperature reactor transients these bubbles act as sinks for fission gas atoms and vacancies and can give rise to large volumetric swellings, sometimes of the order of 10%. Under irradiation conditions, the nucleation and growth of these bubbles is determined by a balance between irradiation-induced nucleation, diffusional growth and an irradiation induced re-solution mechanism. This conceptual picture is, however, incomplete because in the absence of irradiation the model predicts that the bubble population present from the pre-irradiation would act as the dominant sink for fission gas atoms resulting in large intra-granular swellings and little or no fission gas release. In practice, large fission gas releases are observed from post-irradiation annealed fuel. A recent series of experiments addressed the issue of fission gas release and swelling in post-irradiation annealed UO 2 originating from Advanced Gas Cooled Reactor (AGR) fuel which had been ramp tested in the Halden Test reactor. Specimens of fuel were subjected to transient heating at ramp rates of 0.5 deg. C/s and 20 deg. C/s to target temperatures between 1600 deg. C and 1900 deg. C. The release of fission gas was monitored during the tests. Subsequently, the fuel was subjected to post-irradiation examination involving detailed Scanning Electron Microscopy (SEM) analysis. Bubble-size distributions were obtained from seventeen specimens, which entailed the measurement of nearly 26,000 intra-granular bubbles. The analysis reveals that the bubble densities remain approximately invariant during the anneals and the bubble-size distributions exhibit long exponential tails in which the largest bubbles are present in concentrations of 10 4 or 10 5 lower than the concentrations of the average sized bubbles. Detailed modelling of the bubble

  16. KEY RESULTS FROM IRRADIATION AND POST-IRRADIATION EXAMINATION OF AGR-1 UCO TRISO FUEL

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul A.; Hunn, John D.; Petti, David A.; Morris, Robert N.

    2016-11-01

    The AGR-1 irradiation experiment was performed as the first test of tristructural isotropic (TRISO) fuel in the US Advanced Gas Reactor Fuel Development and Qualification Program. The experiment consisted of 72 right cylinder fuel compacts containing approximately 3×105 coated fuel particles with uranium oxide/uranium carbide (UCO) fuel kernels. The fuel was irradiated in the Advanced Test Reactor for a total of 620 effective full power days. Fuel burnup ranged from 11.3 to 19.6% fissions per initial metal atom and time average, volume average irradiation temperatures of the individual compacts ranged from 955 to 1136°C. This paper focuses on key results from the irradiation and post-irradiation examination, which revealed a robust fuel with excellent performance characteristics under the conditions tested and have significantly improved the understanding of UCO coated particle fuel irradiation behavior within the US program. The fuel exhibited a very low incidence of TRISO coating failure during irradiation and post-irradiation safety testing at temperatures up to 1800°C. Advanced PIE methods have allowed particles with SiC coating failure to be isolated and meticulously examined, which has elucidated the specific causes of SiC failure in these specimens. The level of fission product release from the fuel during irradiation and post-irradiation safety testing has been studied in detail. Results indicated very low release of krypton and cesium through intact SiC and modest release of europium and strontium, while also confirming the potential for significant silver release through the coatings depending on irradiation conditions. Focused study of fission products within the coating layers of irradiated particles down to nanometer length scales has provided new insights into fission product transport through the coating layers and the role various fission products may have on coating integrity. The broader implications of these results and the application of

  17. Post-irradiation examination and R and D programs using irradiated fuels at KAERI

    International Nuclear Information System (INIS)

    Chun, Yong Bum; Min, Duck Kee; Kim, Eun Ka and others

    2000-12-01

    This report describes the Post-Irradiation Examination(PIE) and R and D programs using irradiated fuels at KAERI. The objectives of post-irradiation examination (PIE) for the PWR irradiated fuels, CANDU fuels, HANARO fuels and test fuel materials are to verify the irradiation performance and their integrity as well as to construct a fuel performance data base. The comprehensive utilization program of the KAERI's post-irradiation examination related nuclear facilities such as Post-Irradiation Examination Facility (PIEF), Irradiated Materials Examination Facility (IMEF) and HANARO is described

  18. Post-irradiation examination and R and D programs using irradiated fuels at KAERI

    International Nuclear Information System (INIS)

    Chun, Yong Bum; So, Dong Sup; Lee, Byung Doo; Lee, Song Ho; Min, Duck Kee

    2001-09-01

    This report describes the Post-Irradiation Examination(PIE) and R and D programs using irradiated fuels at KAERI. The objectives of post-irradiation examination (PIE) for the PWR irradiated fuels, CANDU fuels, HANARO fuels and test fuel materials are to verify the irradiation performance and their integrity as well as to construct a fuel performance data base. The comprehensive utilization program of the KAERI's post-irradiation examination related nuclear facilities such as Post-Irradiation Examination Facility (PIEF), Irradiated Materials Examination Facility (IMEF) and HANARO is described

  19. New facility for post irradiation examination of neutron irradiated beryllium

    International Nuclear Information System (INIS)

    Ishitsuka, Etsuo; Kawamura, Hiroshi

    1995-01-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800 degrees C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and 60 Co;7.4 MBq/day

  20. Report of Post Irradiation Examination for Dry Process Fuel

    International Nuclear Information System (INIS)

    Par, Jang Jin; Jung, I. H.; Kang, K. H.; Moon, J. S.; Lee, C. R.; Ryu, H. J.; Song, K. C.; Yang, M. S.; Yoo, B. O.; Jung, Y. H.; Choo, Y. S.

    2006-08-01

    The spent PWR fuel typically contains 0.9 wt.% of fissile uranium and 0.6 wt.% of fissile plutonium, which exceeds the natural uranium fissile content of 0.711 wt.%. The neutron economy of a CANDU reactor is sufficient to utilize the DUPIC fuel, even though the neutron-absorbing fission products contained in the spent PWR fuel were remained in the DUPIC fuel. The DUPIC fuel cycle offers advantages to the countries operating both the PWR and CANDU reactors, such as saving the natural uranium, reducing the spent fuel in both PWR and CANDU, and acquiring the extra energy by reuse of the PWR spent fuel. This report contains the results of post-irradiation examination of the DUPIC fuel irradiated four times at HANARO from May 2000 to August 2006 present except the first irradiation test of simulated DUPIC fuel at HANARO on August 1999

  1. Post irradiation examination of control rod assembly of FBTR

    International Nuclear Information System (INIS)

    Anandaraj, V.; Raghu, N.; Venkiteswaran, C.N.; Visweswaran, P.; Vijayakumar, Ran; Jayaraj, V.V.; Padmaprabu, P.; Saravanan, T.; Philip, John; Muralidharan, N.G.; Joseph, Jojo; Kasiviswanathan, K.V.

    2010-01-01

    Six control rods with boron carbide pellets are used in FBTR for shutdown and control of reactor power. One control rod after being subjected to a fluence level of 7.2 x 10 22 n/cm 2 was received for post irradiation examination (PIE) to assess its irradiation behavior and to investigate the incident of dropping of control rod. Examinations carried out include precise dimensional measurements to investigate the possibility of interference between the control rod and outer sheath, Neutron radiography and x-radiograph to assess the integrity of the boron carbide pellets and other internals, density measurements to assess the swelling behaviour of boron carbide pellets and metallographic examinations to study the cracking behaviour and microstructural changes in the pellet and the clad. Depletion of B 10 in the pellet was studied using time of flight mass spectrometry. The paper highlights the examinations and results of the PIE carried out. (author)

  2. Post Irradiation Capabilities at the Idaho National Laboratory

    International Nuclear Information System (INIS)

    Schulthess, J.L.; Rosenberg, K.E.

    2011-01-01

    The U.S. Department of Energy (DOE), Office of Nuclear Energy (NE) oversees the efforts to ensure nuclear energy remains a viable option for the United States. A significant portion of these efforts are related to post-irradiation examinations (PIE) of highly activated fuel and materials that are subject to the extreme environment inside a nuclear reactor. As the lead national laboratory, Idaho National Laboratory (INL) has a rich history, experience, workforce and capabilities for performing PIE. However, new advances in tools and techniques for performing PIE now enable understanding the performance of fuels and materials at the nano-scale and smaller level. Examination at this level is critical since this is the scale at which irradiation damage occurs. The INL is on course to adopt these advanced tools and techniques to develop a comprehensive nuclear fuels and materials characterization capability that is unique in the world. Because INL has extensive PIE capabilities currently in place, a strong foundation exist to build upon as new capabilities are implemented and work load increases. In the recent past, INL has adopted significant capability to perform advanced PIE characterization. Looking forward, INL is planning for the addition of two facilities that will be built to meet the stringent demands of advanced tools and techniques for highly activated fuels and materials characterization. Dubbed the Irradiated Materials Characterization Laboratory (IMCL) and Advanced Post Irradiation Examination Capability, these facilities are next generation PIE laboratories designed to perform the work of PIE that cannot be performed in current DOE facilities. In addition to physical capabilities, INL has recently added two significant contributors to the Advanced Test Reactor-National Scientific User Facility (ATR-NSUF), Oak Ridge National Laboratory and University of California, Berkeley.

  3. On the determination of the post-irradiation time from the glow curve of TLD-100

    International Nuclear Information System (INIS)

    Weinstein, M.; German, U.; Dubinsky, S.; Alfassi, Z.B.

    2003-01-01

    The ratio of peak 3 to the sum of peaks 4 + 5 in TLD-100 was measured for various pre-irradiation and post-irradiation time periods, under conditions characteristic of routine personal dosimetry. It was confirmed that the value of this ratio depends only on the elapsed time between the prior readout and the present one, independent of the moment when the irradiation took place during the total time interval (storage time). This effect indicates that fading of peak 3 seems to be due mainly to changes in the unoccupied traps, and not to decay of trapped charges, being almost independent of the presence of electrons or holes in the traps. This observation leads to the conclusion that the suggestions in the past to use the decay of peak 3 in TLD-100 for the measurement of the elapsed time between irradiation and readout may have been wrong. On the other hand, the decay of peak 2 can be used to measure the elapsed time from irradiation, since the rate of decay is different when related to pre-irradiation and post-irradiation times, indicating a much higher decay rate of the trapped charges (Randall-Wilkins decay). However, because of the fast decay rate of peak 2, its use for determination of the elapsed time since irradiation is of little practical significance. (author)

  4. Protective effect of plant polysaccharides against radiation injury

    International Nuclear Information System (INIS)

    Wang Bingji; Huang Shafei; Cheng Lurong

    1989-01-01

    A series of polysaccharides have been isolated from Chinese traditional medicinal herbs and tested in mice subjected to ionizing radiation for their protective action. The polysaccharides from different origins showed various degrees of radioprotection. Those isolated from Hericium erinaceus and Armillaria mellea showed a higher radioprotective effect than some other polysaccharides. They could increase the survival rate of irradiated mice to 60%. But the polysaccheride separated from Apocynum venetum has negligible effect. In general, most of these polysaccharides are effective only on administration before irradiation. No apparent protection was observed when given post irradiation. The polysaccharide isolated from Armillaria venetum could raise the survival rate of mice irradiated by lethal dose of γ-rays to 58%. It is effective even when administered after irradiation. Some work has been carried out to clarify the mechanism of radioprotective action of polysaccharides. Protection of hemapoietic organs, regulation of immunological system, induction of release of some endogeneous bioactive substances in the organism and reduction of oxygen tension in some vital tissues may be correlated with the protection of organism against radiation injury

  5. Free radical generation in post-irradiation period: an evidence from the conversion of xanthine dehydrogenase into xanthine oxidase

    International Nuclear Information System (INIS)

    Kale, R.K.

    2003-01-01

    Xanthine oxidoreductase (XOR) system which consists of xanthine dehydrogenase (XDH) and xathine oxidase (XO), is one of the major sources of free radicals in biological systems. XOR system is pre-dominantly present as XDH in the normal tissue and converts into free radical generating XO-Form in the damaged tissue. Therefore, XO-Form of XOR system, is expected to be mainly found in the radiolytically damaged tissue. In such an event, XO may catalyze the generation of free radicals and potentiate the radiation effects in post-irradiation period. Recent findings on the effect of ionizing radiation on XOR system in the liver of mice, peroxidative damage and lactate dehydrogenase support this possibility. From these results it has been hypothized that free radical generating systems could be activated in the radiolytically damaged cell and in turn contribute to the cause and complications of late effects and their persistence in post-irradiation period. This aspect may have great significance in understanding the radiation - induced damages. It may also have serious implication in various fields like radiation therapy, health physics, carcinogenesis, space travelling radiation exposures and post nuclear accident care. Further, it is suggested that efforts need to be made to search more system(s) which could be activated particularly at lower doses of radiation and generate free radicals in post-irradiation period

  6. Post-irradiation hyperamylasemia as a biological dosimeter

    International Nuclear Information System (INIS)

    Dubray, Bernard; Girinski, Theo; Hennequin, Christophe; Socie, Gerard; Bonnay, Marc; Cosset, J.M.; Thames, H.D.; Becciolini, Aldo; Porciani, Sauro

    1992-01-01

    Serum alpha-amylasemia was measured before and 24 h after either total body (31 patients) or localized irradiation including salivary glands (40 patients) or pancreatic area (22 patients). A significant increase in amylasemia was observed for doses to the parotid glands larger than 0.5Gy. A sigmoid function of dose was fitted to the data and predicted a maximum amylasemia level for doses larger than 4Gy and smaller than 10Gy. Raw data from other published series were adequately described by the same model. However, confidence limits of parameters remained wide, because of a considerable interindividual variability. Post-irradiation hyperamylasemia appears to provide good criteria for triage of accidentally irradiated patients: 24 h after a dose larger than 2Gy to the parotid glands, 91% of patients had an amylasemia level higher than 2.5-fold the upper normal value (sensitivity). Conversely, 96% had their serum amylasemia lower than 2.5-fold the upper normal value when dose was smaller than 2Gy (specificity). However, a retrospective estimation of the absorbed dose (dosimetry) is not likely to be very precise because of the large interindividual variability. (author). 21 ref.; 1 fig.; 3 tabs

  7. Post-irradiation examinations of THERMHET composite fuels for transmutation

    Science.gov (United States)

    Noirot, J.; Desgranges, L.; Chauvin, N.; Georgenthum, V.

    2003-07-01

    The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl 2O 4 spinel inert matrix and around 40% weight of UO 2 to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

  8. Post-irradiation examinations of THERMHET composite fuels for transmutation

    Energy Technology Data Exchange (ETDEWEB)

    Noirot, J. E-mail: jnoirot@cea.fr; Desgranges, L.; Chauvin, N.; Georgenthum, V

    2003-07-01

    The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl{sub 2}O{sub 4} spinel inert matrix and around 40% weight of UO{sub 2} to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

  9. Post-irradiation examinations of THERMHET composite fuels for transmutation

    International Nuclear Information System (INIS)

    Noirot, J.; Desgranges, L.; Chauvin, N.; Georgenthum, V.

    2003-01-01

    The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl 2 O 4 spinel inert matrix and around 40% weight of UO 2 to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour

  10. Post-irradiation examination of overheated fuel bundles

    International Nuclear Information System (INIS)

    Sears, D.F.; Primeau, M.F.; Leach, D.A.

    1995-01-01

    Post-irradiation examinations (PIE) were conducted on prototype 43-element CANDU fuel bundles that overheated during test irradiations in the NRU reactor. PIE revealed that the bundles remained physically intact, but on several elements the Zr-4 sheath collapsed into axial gaps between the pellet stack and end caps, between adjacent pellets within the stacks, and into missing pellet chips and cracks. Helium pressurization tests showed that none of the collapsed elements leaked. Hydride blisters were discovered on a few elements, but the source of the hydrogen was not linked to a breach of the cladding or end caps. These defects were attributed to primary hydriding. Microstructural changes in the fuel and cladding indicate that the cladding-was briefly exposed to temperatures in the range 600-800 o C and pressures above 11.2 MPa. The results show that Zr-4 cladding behaves in a highly ductile manner during such transient, high-temperature and high-pressure excursions. (author)

  11. Post-irradiation examination of overheated fuel bundles

    International Nuclear Information System (INIS)

    Sears, D.F.; Primeau, M.F.; Leach, D.A.

    1997-08-01

    Post-irradiation examinations (PIE) were conducted on prototype 43-element CANDU fuel bundles that overheated during test irradiations in the NRU reactor. PIE revealed that the bundles remained physically intact, but on several elements the Zr-4 sheath collapsed into axial gaps between the pellet stack and end caps, between adjacent pellets within the stacks, and into missing pellet chips and cracks. Helium pressurization tests showed that none of the collapsed elements leaked. Hydride blisters were discovered on a few elements, but the source of the hydrogen was.not linked to a breach of the cladding or end caps. These defects were attributed to primary hydriding. Microstructural changes in the fuel and cladding indicate that the cladding was briefly exposed to temperatures in the range 600-800 o C and pressures above 11.2MPa. The results show that Zr-4 cladding behaves in a highly ductile manner during such transient, high-temperature and high-pressure excursions. (author)

  12. The operation of post-irradiation examination facility

    International Nuclear Information System (INIS)

    Kim, Eun Ka; Min, Duk Ki; Lee, Young Kil

    1994-12-01

    The operation of post-irradiation examination facility was performed as follow. HVAC and pool water treatment system were continuously operated, and radiation monitoring in PIE facility has been carried out to maintain the facility safely. Inspection of the fuel assembly (F02) transported from Kori Unit 1 was performed in pool, and fuel rods extracted from the fuel assembly (J44) of Kori Unit 2 NPP were examined in hot cell. A part of deteriorated pipe line of drinking water was exchanged for stainless steel pipe to prevent leaking accidents. Halon gas system was also installed in the exhausting blower room for fire fighting. And IAEA inspection camera for safeguard of nuclear materials was fixed at the wall in pool area. Radiation monitoring system were improved to display the area radioactive value at CRT monitor in health physics control room. And automatic check system for battery and emergency diesel generator was developed to measure the voltage and current of them. The performance test of oxide thickness measuring device installed in hot cell for irradiated fuel rod and improvement of the device were performed, and good measuring results using standard sample were obtained. The safeguard inspection of nuclear materials and operation inspection of the facility were carried out through the annual operation inspection, quarterly IAEA inspection and quality assurance auditing. 26 tabs., 43 figs., 14 refs. (Author) .new

  13. Protective effects of the fermented milk Kefir on X-ray irradiation-induced intestinal damage in B6C3F1 mice

    International Nuclear Information System (INIS)

    Teruya, Kiichiro; Nakamichi, Noboru; Shirahata, Sanetaka; Myojin-Maekawa, Yuki; Shimamoto, Fumio; Watanabe, Hiromitsu; Tokumaru, Koichiro; Tokumaru, Sennosuke

    2013-01-01

    Gastrointestinal damage associated with radiation therapy is currently an inevitable outcome. The protective effect of Kefir was assessed for its usefulness against radiation-induced gastrointestinal damage. A Kefir supernatant was diluted by 2- or 10-fold and administered for 1 week prior to 8 Gray (Gy) X-ray irradiation at a dose rate of 2 Gy/min, with an additional 15d of administration post-irradiation. The survival rate of control mice with normal drinking water dropped to 70% on days 4 through 9 post-irradiation. On the other hand, 100% of mice in the 10- and 2-fold-diluted Kefir groups survived up to day 9 post-irradiation (p<0.05 and p<0.01, respectively). Examinations for crypt regeneration against 8, 10 and 12 Gy irradiation at a dose rate of 4 Gy/min revealed that the crypt number was significantly increased in the mice administered both diluted Kefir solutions (p<0.01 for each). Histological and immunohistochemical examinations revealed that the diluted Kefir solutions protected the crypts from radiation, and promoted crypt regeneration. In addition, lyophilized Kefir powder was found to significantly recover the testis weights (p<0.05), but had no effects on the body and spleen weights, after 8 Gy irradiation. These findings suggest that Kefir could be a promising candidate as a radiation-protective agent. (author)

  14. Kinetic Monte Carlo simulation of nanostructural evolution under post-irradiation annealing in dilute FeMnNi

    Energy Technology Data Exchange (ETDEWEB)

    Chiapetto, M. [SCK-CEN, Nuclear Materials Science Institute, Mol (Belgium); Unite Materiaux et Transformations (UMET), UMR 8207, Universite de Lille 1, ENSCL, Villeneuve d' Ascq (France); Becquart, C.S. [Unite Materiaux et Transformations (UMET), UMR 8207, Universite de Lille 1, ENSCL, Villeneuve d' Ascq (France); Laboratoire commun EDF-CNRS, Etude et Modelisation des Microstructures pour le Vieillissement des Materiaux (EM2VM) (France); Domain, C. [EDF R and D, Departement Materiaux et Mecanique des Composants, Les Renardieres, Moret sur Loing (France); Laboratoire commun EDF-CNRS, Etude et Modelisation des Microstructures pour le Vieillissement des Materiaux (EM2VM) (France); Malerba, L. [SCK-CEN, Nuclear Materials Science Institute, Mol (Belgium)

    2015-01-01

    Post-irradiation annealing experiments are often used to obtain clearer information on the nature of defects produced by irradiation. However, their interpretation is not always straightforward without the support of physical models. We apply here a physically-based set of parameters for object kinetic Monte Carlo (OKMC) simulations of the nanostructural evolution of FeMnNi alloys under irradiation to the simulation of their post-irradiation isochronal annealing, from 290 to 600 C. The model adopts a ''grey alloy'' scheme, i.e. the solute atoms are not introduced explicitly, only their effect on the properties of point-defect clusters is. Namely, it is assumed that both vacancy and SIA clusters are significantly slowed down by the solutes. The slowing down increases with size until the clusters become immobile. Specifically, the slowing down of SIA clusters by Mn and Ni can be justified in terms of the interaction between these atoms and crowdions in Fe. The results of the model compare quantitatively well with post-irradiation isochronal annealing experimental data, providing clear insight into the mechanisms that determine the disappearance or re-arrangement of defects as functions of annealing time and temperature. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Investigation of neutron irradiated reactor vessel steels using post-irradiation annealing techniques

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, Hayato; Fukuya, Koji [Institute of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2001-09-01

    The matrix damage is known to be a major factor that contributes to embrittlement and hardening of irradiated reactor vessel steels, and is assumed to be composed of the point defect clusters. However field emission gun scanning transmission electron microscopy (FEGSTEM) and atom probe (AP) could not detect any evidence of the matrix damage. In this study, post irradiation annealing experiments combining positron annihilation lineshape analysis (PALA) and hardness experiments were applied to an actual surveillance test specimen and a sample of reactor vessel steel irradiated in a material test reactor (MTR), in order to investigate the matrix damage recovery behavior and its contribution to hardening. It was confirmed that higher fluence increased the hardness and the volume fraction of open volume defects and that higher flux decreased the thermal stability of matrix damage and the effect on hardening. The contribution of matrix damage to hardening could be estimated to be below 30%. (author)

  16. Design of a decontamination section of the post-irradiation examination laboratory

    International Nuclear Information System (INIS)

    Homberger, Victor; Coronel, Ruben R.; Laumann, Victor; Perez, Jorge O.; Quinteros, Andrea N.; Ratner, Marcos

    1999-01-01

    The Post-Irradiation Examination Laboratory activities include the decontamination of expensive equipment of different sizes and weight, involving the complexity and extension of the necessary decontamination. A decontamination section has been designed for that purpose. (author)

  17. MR characterization of post-irradiation soft tissue edema

    International Nuclear Information System (INIS)

    Richardson, M.L.; Zink-Brody, G.C.; Patten, R.M.; Koh Wuijin; Conrad, E.U.

    1996-01-01

    Objective. Radiation therapy is often used to treat bone und soft tissue neoplasms, and commonly results in soft tissue edema in the radiation field. However, the time course, distribution and degree of this edema have not been well characterized. Our study was carried out to better define these features of the edema seen following neutron and photon radiation therapy. Results. In general, soft tissue signal intensity in the radiation field initially increased over time, peaking at about 6 months for neutron-treated patients and at about 12-18 months for photon-treated patients. Signal intensity then decreased slowly over time. However, at the end of the follow-up period, signal intensity remained elevated for most patients in both groups. Signal intensity in a particular tissue was greater and tended to persist longer on STIR sequences than on T2-weighted sequences. Survival analysis of signal intensity demonstrated much longer edema survival times for neutron-treated patients than for photon-treated patients. Signal intensity increase in the intramuscular septa persisted for much longer than for fat or muscle. A mild increase in size was noted in the subcutaneous fat and intramuscular septa. Muscle, on the other hand, showed a decrease in size following treatment. This was mild for the photon-treated group and more marked for the neutron-treated group. Conclusions. There is a relatively wide variation in the duration and degree of post-irradiation edema in soft tissues. This edema seems to persist longer in the intramuscular septa than in fat or muscle. Although the duration of follow-up was limited, our study suggests that this edema resolves in roughly half the photon-treated patients within 2-3 years post-treatment and in less than 20% of neutron-treated patients by 3-4 years post-treatment. Muscle atrophy was seen in both photon- and neutron-treated patients, but was more severe in the neutron-treated group. (orig./vhe). With 4 figs

  18. Development of a hot cell for post-irradiation analysis of nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Selma S.C.; Silva Junior, Silverio Ferreira da; Loureiro, Joao Roberto M. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: selmasallam@yahoo.com.br, e-mail: silvasf@cdtn.br, e-mail: jrmattos@cdtn.br

    2009-07-01

    Post irradiation examinations of nuclear fuels are performed in order to verify their in-service behavior. Examinations are conducted in compact structures called hot cells, designed to attend the different types of tests and analysis for fuel's characterization. The characterization of fuel microstructure is an activity performed in hot cells. Usually, hot cells for microstructural fuel analysis are designed to allow the metallographic and ceramographic samples preparation and after that, microscopical analysis of the fuel's microstructure. Due to the complexity of the foreseen operations, the severe limitations imposed by the available space into the hot cells, the capabilities of the remote manipulation devices, the procedures of radiological protection and the needs to obtain samples with an adequate surface quality for microscopic analysis, the design of a hot cell for fuel samples preparation presents a high level of complexity. In this paper, the methodology used to develop a hot cell facility for nuclear fuel's metallographic and ceramographic samples preparation is presented. Equipment, devices and systems used in conventional sample preparation processes were evaluated during bench tests. After the necessary adjustments and processes adaptations, they were assembled in a mock-up of the respective hot cell, where they were tested in conditions as realistic as possible, in order to improve the operations and processes to be performed at the real hot cells. (author)

  19. Development of a hot cell for post-irradiation analysis of nuclear fuels

    International Nuclear Information System (INIS)

    Silva, Selma S.C.; Silva Junior, Silverio Ferreira da; Loureiro, Joao Roberto M.

    2009-01-01

    Post irradiation examinations of nuclear fuels are performed in order to verify their in-service behavior. Examinations are conducted in compact structures called hot cells, designed to attend the different types of tests and analysis for fuel's characterization. The characterization of fuel microstructure is an activity performed in hot cells. Usually, hot cells for microstructural fuel analysis are designed to allow the metallographic and ceramographic samples preparation and after that, microscopical analysis of the fuel's microstructure. Due to the complexity of the foreseen operations, the severe limitations imposed by the available space into the hot cells, the capabilities of the remote manipulation devices, the procedures of radiological protection and the needs to obtain samples with an adequate surface quality for microscopic analysis, the design of a hot cell for fuel samples preparation presents a high level of complexity. In this paper, the methodology used to develop a hot cell facility for nuclear fuel's metallographic and ceramographic samples preparation is presented. Equipment, devices and systems used in conventional sample preparation processes were evaluated during bench tests. After the necessary adjustments and processes adaptations, they were assembled in a mock-up of the respective hot cell, where they were tested in conditions as realistic as possible, in order to improve the operations and processes to be performed at the real hot cells. (author)

  20. Main results of post-irradiation examinations of new-generation fuel assemblies VVER-1000

    International Nuclear Information System (INIS)

    Zvir, E.; Markov, D.; Polenok, V.; Zhitelev, V.; Kobylyansky, G.

    2009-01-01

    To increase the competitiveness of Russian nuclear fuel at the foreign market and to improve its technical and economic performance in order to provide a necessary level of safety, it is necessary to solve certain important tasks: Increase of fuel burn-up; Extension of operational lifetime of fuel assemblies and operational reliability of nuclear fuel; Introduction of cost-beneficial and flexible fuel cycles. Alternative fuel assemblies TVSA VVER-1000 and TVS-2 are used as a basis to optimize the nuclear fuel and develop advanced fuel cycles for nuclear power plants with VVER-1000 reactor types. Four fuel assemblies TVSA operated during 1 and up to 6 reactor cycles, reference fuel assembly TVS-2 operated during three reactor cycles and achieved an average fuel burnup of 48MW·day/kgU as well as failed fuel assembly TVS-2 operated during one cycle were examined at RIAR in recent years. The main objectives of these examinations were to obtain experimental data in support of operational integrity of products or to find out reasons of their failure. The performed post-irradiation examinations confirmed the operational integrity of alternative fuel assemblies TVSA including their geometrical stability up to the average fuel burnup of 55 MW·day/kgU over the fuel assembly (FA) (up to the maximal fuel burnup of ∼73 MW·day/kgU in fuel rods) and of TVS-2 up to the average fuel burnup of 48 MW·day/kgU over the fuel assembly. The changes introduced in the design of VVER-1000 fuel assembly during the development of alternative fuel assembly TVSA and TVS-2 did not make any negative effect on fuel rods. It was proved that causes of fuel rod failure were not related to design features of fuel assemblies. The design features and operating conditions of fuel assemblies under examinations are briefly described. Post-irradiation examinations proved the geometrical stability of fuel assemblies TVSA and TVS-2 under operation up to the fuel burnup of ∼50 MW day/kgU, as for the

  1. Survey of post-irradiation examinations made of mixed carbide fuels

    International Nuclear Information System (INIS)

    Coquerelle, M.

    1997-01-01

    Post-irradiation examinations on mixed carbide, nitride and carbonitride fuels irradiated in fast flux reactors Rapsodie and DFR were carried out during the seventies and early eighties. In this report, emphasis was put on the fission gas release, cladding carburization and head-end gaseous oxidation process of these fuels, in particular, of mixed carbides. (author). 8 refs, 16 figs, 3 tabs

  2. Studies on Post-Irradiation DNA Degradation in Micrococcus Radiodurans, Strain RII51

    DEFF Research Database (Denmark)

    Auda, H.; Emborg, C.

    1973-01-01

    The influence of irradiation condition on post-irradiation DNA degradation was studied in a radiation resistant mutant of M. radiodurans, strain ${\\rm R}_{{\\rm II}}5$. After irradiation with 1 Mrad or higher more DNA is degraded in cells irradiated in wet condition than in cells irradiated with t...

  3. Fabrication, irradiation and post-irradiation examinations of MO2 and UO2 sphere-pac and UO2 pellet fuel pins irradiated in a PWR loop

    International Nuclear Information System (INIS)

    Linde, A. van der; Lucas Luijckx, H.J.B.; Verheugen, J.H.N.

    1981-04-01

    Three fuel pin bundles, R-109/1, 2 and 3, were irradiated in a PWR loop in the HFR at Petten during respectively 131, 57 and 57 effective full power days at average powers of approximately 39 kW.m -1 and at peak powers of approximately 60 kW.m -1 . The results of the post-irradiation examinations of these fuel bundles are presented. (Auth.)

  4. Shear Wave Elastography--A New Quantitative Assessment of Post-Irradiation Neck Fibrosis.

    Science.gov (United States)

    Liu, K H; Bhatia, K; Chu, W; He, L T; Leung, S F; Ahuja, A T

    2015-08-01

    Shear wave elastography (SWE) is a new technique which provides quantitative assessment of soft tissue stiffness. The aim of this study was to assess the reliability of SWE stiffness measurements and its usefulness in evaluating post-irradiation neck fibrosis. 50 subjects (25 patients with previous radiotherapy to the neck and 25 sex and age-matched controls) were recruited for comparison of SWE stiffness measurements (Aixplorer, Supersonic Imagine). 30 subjects (16 healthy individuals and 14 post-irradiated patients) were recruited for a reliability study of SWE stiffness measurements. SWE stiffness measurements of the sternocleidomastoid muscle and the overlying subcutaneous tissues of the neck were made. The cross-sectional area and thickness of the sternocleidomastoid muscle and the overlying subcutaneous tissue thickness of the neck were also measured. The post-irradiation duration of the patients was recorded. The intraclass correlation coefficients for the intraoperator and interoperator reliability of deep and subcutaneous tissue SWE stiffness ranged from 0.90-0.99 and 0.77-0.94, respectively. The SWE stiffness measurements (mean +/- SD) of deep and subcutaneous tissues were significantly higher in the post-irradiated patients (64.6 ± 46.8 kPa and 63.9 ± 53.1 kPa, respectively) than the sex and age-matched controls (19.9 ± 7.8 kPa and 15.3 ± 8.37 respectively) (p < 0.001). The SWE stiffness increased with increasing post-irradiation therapy duration in the Kruskal Wallis test (p < 0.001) and correlated with muscle atrophy and subcutaneous tissue thinning (p < 0.01). SWE is a reliable technique and may potentially be an objective and specific tool in quantifying deep and subcutaneous tissue stiffness, which in turn reflects the severity of neck fibrosis. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Fission gas release during post irradiation annealing of large grain size fuels from Hinkley point B

    International Nuclear Information System (INIS)

    Killeen, J.C.

    1997-01-01

    A series of post-irradiation anneals has been carried out on fuel taken from an experimental stringer from Hinkley Point B AGR. The stringer was part of an experimental programme in the reactor to study the effect of large grain size fuel. Three differing fuel types were present in separate pins in the stringer. One variant of large grain size fuel had been prepared by using an MgO dopant during fuel manufactured, a second by high temperature sintering of standard fuel and the third was a reference, 12μm grain size fuel. Both large grain size variants had similar grain sizes around 35μm. The present experiments took fuel samples from highly rated pins from the stringer with local burn-up in excess of 25GWd/tU and annealed these to temperature of up to 1535 deg. C under reducing conditions to allow a comparison of fission gas behaviour at high release levels. The results demonstrate the beneficial effect of large grain size on release rate of 85 Kr following interlinkage. At low temperatures and release rates there was no difference between the fuel types, but at temperatures in excess of 1400 deg. C the release rate was found to be inversely dependent on the fuel grain size. The experiments showed some differences between the doped and undoped large grains size fuel in that the former became interlinked at a lower temperature, releasing fission gas at an increased rate at this temperature. At higher temperatures the grain size effect was dominant. The temperature dependence for fission gas release was determined over a narrow range of temperature and found to be similar for all three types and for both pre-interlinkage and post-interlinkage releases, the difference between the release rates is then seen to be controlled by grain size. (author). 4 refs, 7 figs, 3 tabs

  6. Fission gas release during post irradiation annealing of large grain size fuels from Hinkley point B

    Energy Technology Data Exchange (ETDEWEB)

    Killeen, J C [Nuclear Electric plc, Barnwood (United Kingdom)

    1997-08-01

    A series of post-irradiation anneals has been carried out on fuel taken from an experimental stringer from Hinkley Point B AGR. The stringer was part of an experimental programme in the reactor to study the effect of large grain size fuel. Three differing fuel types were present in separate pins in the stringer. One variant of large grain size fuel had been prepared by using an MgO dopant during fuel manufactured, a second by high temperature sintering of standard fuel and the third was a reference, 12{mu}m grain size fuel. Both large grain size variants had similar grain sizes around 35{mu}m. The present experiments took fuel samples from highly rated pins from the stringer with local burn-up in excess of 25GWd/tU and annealed these to temperature of up to 1535 deg. C under reducing conditions to allow a comparison of fission gas behaviour at high release levels. The results demonstrate the beneficial effect of large grain size on release rate of {sup 85}Kr following interlinkage. At low temperatures and release rates there was no difference between the fuel types, but at temperatures in excess of 1400 deg. C the release rate was found to be inversely dependent on the fuel grain size. The experiments showed some differences between the doped and undoped large grains size fuel in that the former became interlinked at a lower temperature, releasing fission gas at an increased rate at this temperature. At higher temperatures the grain size effect was dominant. The temperature dependence for fission gas release was determined over a narrow range of temperature and found to be similar for all three types and for both pre-interlinkage and post-interlinkage releases, the difference between the release rates is then seen to be controlled by grain size. (author). 4 refs, 7 figs, 3 tabs.

  7. Gamma radiolysis and post-irradiation leaching of ion exchange resins

    International Nuclear Information System (INIS)

    Traboulsi, A.

    2012-01-01

    The knowledge of the behavior under irradiation and in presence of water of Ion Exchange Resins (IER) is very necessary to predict their impact on the environment during the storage phase and in a possible deep geological disposal. The IER studied are the MB400 mixed bed resin and its 'pure' anionic and cationic components. The experimental strategy used in this work was based on the use of chemometric tools permitting to estimate the effect of the irradiation atmosphere, the dose rate, the absorbed dose and the leaching temperature. The gaseous and water-soluble radiolysis products were analyzed by gas Mass Spectrometry (MS) and Ion Chromatography (IC). The IER generated principally H 2 g, CO 2 g and amines for which quantities depended of the resin nature and the irradiation conditions. The analysis of solid irradiated resins was investigated by Fourier Transformed Infrared (FTIR) and Nuclear Magnetic Resonance ( 13 C NMR) techniques. The last ones revealed structural modifications of the IER solid matrix in function of the experimental conditions. Their behavior in presence of water was studied during 143 days by characterization of the organic matter released after their post-irradiation leaching. The kinetics showed that all the water-soluble components were releasing at the first contact with water. The Total Organic Carbon (TOC) quantity released depends, according to the resin nature, either on the dose, either on the irradiation atmosphere. The dose rate has no effect on the degradation and the leaching of the MB400 resin, which behaved differently than its pure components. (author) [fr

  8. Protective effect of vitamins C and E on Gamma radiation induced Genetic injuries in male mice germ cells

    International Nuclear Information System (INIS)

    Anwar, W.A.; El-Daway, H.A.E.; Tawfik, S.S.M.

    1999-01-01

    The effects of vitamins C and E on meiotic chromosomal metaphase-8 at diakinesis of the mouse to 3 Gy of whole body gamma- irradiation were studied. These vitamins were injected intraperitoneally as acute doses 2 hr before irradiation. Both vitamins significantly reduced the frequencies of chromosomal aberration in spermatic germ cells. The protective effect of vitamin E was greater than that afforded by vitamin C. A combined treatment of both vitamins resulted in additional protection over that offered by each vitamine alone. In all animal groups the most frequent aberration found was translocation in the from of either ring four (R IV) or chain four (C IV). The percentage of each or them was significantly increased in male mice sacrificed after 15 days post-irradiation. Other types of aberrations as autosomal univalent, X-Gamma univalent and polyploidy were rarely present

  9. Pharmacology of post-irradiation damage of blood capillaries

    International Nuclear Information System (INIS)

    Pospisil, J.; Pouckova, P.

    1979-01-01

    Available literature data are summed up on the effect of a number of substances on irradiation damage to blood capillaries. The substances include vitamins, bioflavonoids, serotonine, histamine, bradykinin, ACTH, adrenal hormones, vasopressin, estrogens, prostaglandins, escin 1-butanol, diisopropylfluorophosphate, phenoxybenzamine, 1,4-dihydroxybenzenesulphonic acid derivatives, and xi-aminohexanoic acid. The data include the effects of the substances administered before and after irradiation on blood capillary damage and on mortality. (Ha)

  10. Dose-time relationships for post-irradiation cutaneous telangiectasia

    International Nuclear Information System (INIS)

    Cohen, L.; Ubaldi, S.E.

    1977-01-01

    Seventy-five patients who had received electron beam radiation a year or more previously were studied. The irradiated skin portals were photographed and late reactions graded in terms of the number and severity of telangiectatic lesions observed. The skin dose, number of fractions, overall treatment time and irradiated volume were recorded in each case. A Strandqvist-type iso-effect line was derived for this response. A multi-probit search program also was used to derive best-fitting cell population kinetic parameters for the same data. From these parameters a comprehensive iso-effect table could be computed for a wide range of treatment schedules including daily treatment as well as fractionation at shorter and longer intervals; this provided a useful set of normal tissue tolerance limits for late effects

  11. ORNL capability to conduct post irradiation examination of full-length commercial nuclear fuel rods

    International Nuclear Information System (INIS)

    Spellman, Donald J.

    2007-01-01

    Hot cells at Oak Ridge National Laboratory (ORNL) are nearing completion of a multi-year upgrade program to implement 21. century capabilities to meet the examination demands for higher burnup fuels and the future demands that will come from fuel recycling programs. Fuel reliability and zero tolerance for fuel failure is more than an industry goal. Fuel reliability is becoming a requirement that supports the renaissance of nuclear power generation. Thus, fuel development and management of new forms of waste that will come from programs such as the Global Nuclear Energy Partnership (GNEP) will require extensive use of the flexible, high-quality, technically advanced hot cells at ORNL. ORNL has the capability to perform post irradiation examination (PIE) of irradiated commercial nuclear fuel rods and the management structure to ensure a timely, cost-effective result. ORNL can: 1) Handle the transportation issues, 2) Perform macroscopic fuel rod examinations, 3) Perform microscopic fuel and clad examinations, and 4) Manage legacy material and waste disposal issues from PIE activities. All four of these items will be managed in a way that allows the customer day-to-day access to the results and data. Hot cell examination equipment that is necessary to determine the characteristics and performance of irradiated materials must operate in a hostile environment and is subject to long-term degradation that may result in reliability and quality assurance (QA) issues. ORNL has modernized its hot cell nuclear fuel examination equipment, installing state-of-the-art automated examination equipment and data gathering capabilities. ORNL is planning a major commitment to nuclear fuel examination and development, and future improvements will continue to be made over the next few years. (author)

  12. Biochemical Post-Irradiation Changes and Radiation Indicators: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Streffer, G. [Radiologisches Institut, University of Freiburg, Freiburg im Breisgau, Federal Republic of Germany (Germany)

    1971-03-15

    In a number of mammalian tissues a breakdown of the biological macromolecules, as nucleic acids and proteins, is observed after irradiation. This degradation appears in lymphatic tissues even after a radiation exposure less than 100 R and proceeds with increasing exposure to about 600 R. On the other hand, other biochemical effects are found after the whole-body irradiation of mammals which seem to have some relation to the functional status of the organs and the organisms. It appears therefore useful to classify the biochemical effects of radiation into two groups: (1) Observations which are a consequence of the degradation processes; (2) observations which are a consequence of functional changes. Most investigations in the field of biochemical indicators after irradiation have been concerned with the first class of reactions. The excretion of deoxycytidine, thymidine and pseudouridine have been extensively investigated in animals during recent years. However, in humans the normal deoxycytidine excretion is very low, as this substance is metabolized to a higher degree in humans than in other species. {beta}-aminoisobutyric acid (BAIBA), a metabolite of thymine, was also investigated in this connection. Besides nucleic acids, proteins are broken down in these radiosensitive organs. This leads to an increased content of amino acids for instance in the lymphatic tissues and to an increase in urinary excretion of amino acids. There are two amino acids which play a special role for this discussion: cysteine and tryptophan. Taurine, a metabolite of cysteine, is excreted in the urine to an increased extent after the irradiation of mice, rats and man. Again the enhancement is proportional to the radiation exposure between 100 and 300 R. Another substance which has been extensively studied is creatine. It has been shown that there is a good relationship between radiation exposure (up to about 600 R) and the increased excretion of creatine/creatinine in the urine of rats

  13. Alleviation of acute radiation damages by post-irradiation treatments

    International Nuclear Information System (INIS)

    Kurishita, A.; Ono, T.

    1992-01-01

    Radiation induced hematopoietic and gastro-intestinal damages in mice were tried to alleviate experimentally by post-treatment. Combined treatment of OK-432 and aztreonam clearly prevented the radiation induced sepsis and elevated the survival rate in mice; the survival was 80% in the OK-432 plus aztreonam group while it was 55% in the group treated with OK-432 alone and 0% with saline. Irsogladine maleate, an anti-ulcer drug, increased the survival rate of jejunal crypt stem cells with a clear dose-related trend. The D 0 for irsogladine maleate was 2.8 Gy although it was 2.3 Gy for saline, These findings suggest that some conventional drugs are effective for radiation induced hematopoietic and gastro-intestinal damages and the possibility that they can be applied for people exposed to radiation accidentally. (author)

  14. Post-irradiation abortion: a slaughter of innocents

    International Nuclear Information System (INIS)

    Dalrymple, G.V.; Baker, M.L.

    1977-01-01

    The medical profession and the lay public have not been overly concerned about the effects of diagnostic x-rays or radioactive isotopes until the last decade when radiation was rediscovered to cause damage to the fetus. In addition, radiation is associated with increased incidence of childhood cancer as well as chromosome damage and related birth defects. While some fear of radiation during the embryonic-fetal period, one of great radiosensitivity, is justified, the anxiety has been intensified by the attitudes of some physicians. Instances have occurred in which a patient who had received a very small amount of radiation (from diagnostic x-ray examination) was advised to have an abortion. A foreseeable result of such events has been litigation against involved physicians. Counter-measures that have been suggested are: do not irradiate women known to be pregnant without a firm clinical indication; if accidental iradiation is discovered the actual dose to the fetus should be estimated. Usual diagnostic examination will give fewer than 5 rads to the fetus and such doses do not represent grounds for abortion. For doses of 5-10 rads abortion could be considered and above 10 rads there would be stronger consideration for such a recommendation. other factors to be considered include age of the mother, and environmental factors (medicines, food additives, cigarettes, coffee, etc.). Proper radiologic practice will eliminate or reduce the number of pregnant women irradiated

  15. Post-Irradiation Examination and In-Pile Measurement Techniques for Water Reactor Fuels

    International Nuclear Information System (INIS)

    2009-12-01

    in the 1960s when the construction of NPPs was being started. Evidently it can be assumed that infrastructure with basic unique equipments is old enough, both morally and physically, and needs to be up-graded or replaced. Thus, a sharp increase of the hydrocarbon fuel cost, green-house effect, necessity to construct more safe and efficient NPPs, justification of the lifetime prolongation of the existing NPPs, moral and physical ageing of the hot labs and research reactors equipment lead to the strong necessity to develop more perfect and more precise methods and equipment to examine irradiated components of nuclear reactors, first of all the most expensive one - nuclear fuel. Now the national hot laboratories and material testing reactors usually act as individual independent research establishments without any common and coordinated technical and business strategy towards the future needs and challenges. Even if there are not many joint programs for the development of nuclear power engineering in different countries, the method base and accumulated experience of the in- and post-reactor experiments should be widely shared so as to decrease the cost of this base in each country and to enforce its development. Thus, both problems and results of the application of new techniques to examine nuclear reactor components, as well as the conditions of separate labs should be discussed at the international level. The IAEA technical meetings are one of the most convenient means of arranging such discussion on the problems of the hot labs and research reactors development and application of new original techniques for examination of reactor materials properties. This publication represents a summary and proceedings of the two technical meetings (TMs) organized by IAEA on the subjects of Hot Cell Post-Irradiation Examination (PIE) Techniques and Pool Side Inspection of Water Reactor Fuel Assemblies and Fuel Rod Instrumentation and In-Pile Measurement Techniques. The first TM was

  16. Post irradiation examination of garter springs from Indian PHWRs

    International Nuclear Information System (INIS)

    Dubey, J.S.; Shah, Priti Kotak; Mishra, Prerna; Singh, H.N.; Alur, V.D.; Kumar, Ashwini; Bhandekar, A.; Pandit, K.M.; Anantharaman, S.

    2013-12-01

    Irradiated Zr-2.5Nb-0.5Cu garter springs, belonging to Indian Pressurised Heavy Water Reactors, which had experienced 8 to 10 Effective Full Power Years of operation were subjected to visual, dimensional, chemical, metallographic examination and relevant mechanical tests. Methodology of the tests conducted and results are presented. The digital photographs were used to measure the inner and outer circumferences by image processing. The hydrogen (H) content in the spring coils were measured using Differential Scanning Calorimetry (DSC). In the stretch test, all the irradiated GSs were found to require an additional load, as compared to unirradiated GS, to produce a given amount of residual extension which indicated that the irradiated GSs had undergone significant irradiation hardening. The crush test results showed that the minimum load required to crush the coil or cause a sudden sideways shift in the grips was higher than 400 N/coil, much higher than the design load. The test results indicated that the irradiated GS, after 10 EFPY of operation, have adequate strength and ductility to continue to meet the design intent. Mechanical tests were carried out on irradiated girdle wires taken out of the loose fit garter springs (GS) from (NAPS-1, ∼ 8.5 EFPY) and tight fit garter spring from KAPS-2 (∼ 8.0 EFPY) PHWRs. Tensile tests on the irradiated girdle wires, showed irradiation hardening in the material and reduction in ductility. The irradiated girdle wires have around 4 to 5% residual ductility level against the 15% ductility of unirradiated wire. The fracture surfaces of the irradiated as well as the un-irradiated girdle wires were observed in SEM. (author)

  17. The reduction of radiation damage to the spinal cord by post-irradiation administration of vasoactive drugs

    International Nuclear Information System (INIS)

    Hornsey, S.; Myers, R.; Jenkinson, T.

    1990-01-01

    Radiation induced white matter necrosis in the rat spinal cord is preceded by changes in permeability of the blood brain-barrier, reduced blood flow, and infarction so that the necrosis is an ischemic necrosis. Attempts have been made to modify this developing pathology by the administration of drugs post-irradiation but just prior to the changes in vascular permeability. Verapamyl, a calcium channel blocker, had no effect on the development of ataxia. Dipyridamole, a drug which increases blood flow and reduces thrombosis, delayed and reduced the onset of ataxia. A low iron diet and desferrioxamine which reduces reperfusion injury also delayed and reduced ataxia. These results support the thesis that vascular changes are an important pathway in the development of radiation necrosis and that reperfusion injury is an important factor in the development and exacerbation of radiation damage to the spinal cord

  18. Post irradiation examination of HANARO nucler mini-element fuel (metallographic and density test)

    International Nuclear Information System (INIS)

    Yoo, Byung Ok; Hong, K. P.; Park, D. G.; Choo, Y. S.; Baik, S. J.; Kim, K. H.; Kim, H. C.; Jung, Y. H.

    2001-05-01

    The post irradiation examination of a HANARO mini-element nuclear fuel, KH96C-004, was done in June 6, 2000. The purpose of this project is to evaluate the in-core performance and reliability of mini-element nuclear fuel for HANARO developed by the project T he Nuclear Fuel Material Development of Research Reactor . And, in order to examine the performance of mini-element nuclear fuel in normal output condition, the post irradiation examination of a nuclear fuel bundle composed by 6 mini nuclear fuel rods and 12 dummy fuel rods was performed. Based on these examination results, the safety and reliability of HANARO fuel and the basic data on the design of HANARO nuclear fuel can be ensured and obtained,

  19. Chemical changes after irradiation and post-irradiation storage in tilapia and Spanish mackerel

    International Nuclear Information System (INIS)

    Al-Kahtani, H.A.; Abu-Tarboush, H.M.; Bajaber, A.S.; Atia, M.; Abou-Arab, A.A.; El-Mojaddidi, M.A.

    1996-01-01

    Influence of gamma irradiation (1.5-10 kGy) and post-irradiation storage up to 20 days at 2 +/- 2 degrees C on some chemical criteria of tilapia and spanish mackerel were studied. Total volatile basic nitrogen formation was lower in irradiated fish than in the unirradiated. Irradiation also caused a larger increase in thiobarbituric acid values which continued gradually during storage. Some fatty acids decreased by irradiation treatments at all doses. Thiamin loss was more severe at higher doses (greater than or equal to 4.5 kGy), whereas riboflavin was not affected. Alpha and gamma tocopherols of tilapia and alpha, beta, gamma, and delta tocopherols, in Spanish mackerel, decreased with increased dose and continued to decrease during 20-day post-irradiation storage

  20. Preliminary test results for post irradiation examination on the HTTR fuel

    International Nuclear Information System (INIS)

    Ueta, Shohei; Umeda, Masayuki; Sawa, Kazuhiro; Sozawa, Shizuo; Shimizu, Michio; Ishigaki, Yoshinobu; Obata, Hiroyuki

    2007-01-01

    The future post-irradiation program for the first-loading fuel of the HTTR is scheduled using the HTTR fuel handling facilities and the Hot Laboratory in the Japan Materials Testing Reactor (JMTR) to confirm its irradiation resistance and to obtain data on its irradiation characteristics in the core. This report describes the preliminary test results and the future plan for a post-irradiation examination for the HTTR fuel. In the preliminary test, fuel compacts made with the same SiC-coated fuel particle as the first loading fuel were used. In the preliminary test, dimension, weight, fuel failure fraction, and burnup were measured, and X-ray radiograph, SEM, and EPMA observations were carried out. Finally, it was confirmed that the first-loading fuel of the HTTR showed good quality under an irradiation condition. The future plan for the post-irradiation tests was described to confirm its irradiation performance and to obtain data on its irradiation characteristics in the HTTR core. (author)

  1. Clinical analysis of post-irradiation sensorineural hearing loss in patients suffering from nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Lu Xueguan; Liu Zhiyong; Zhang Liyuan; Tian Ye

    2005-01-01

    Objective: To investigate the incidence of post-irradiation sensorineural hearing loss (SNHL) in patients suffering from nasopharyngeal carcinoma and to evaluate its potentially contributing factors. Methods: Pure tonetest and impedance audiography were carried out in patients suffering from nasopharyngeal carcinoma with a post-irradiation follow-up time over 1 year. Additionally, the test results were combined with clinical data and analyzed retrospectively. Results: The follow-up time of all patients ranged from 12 to 94 months (median 53 months). The incidences of SNHL at low and high frequencies were 8% and 42% respectively. Univariate analysis showed that patient's age and follow-up time affected the incidence of SNHL at high frequencies (t=2.051, P=0.0269; t=2.978, P=0.0011), but sex, preirradiation subjective hearing loss, irradiation dose and chemotherapy including cisplatin had no significance. Multivariate analysis by Binary Logistic Regression revealed that the risk of SNHL was correlated with patient's age and follow-up time (P=0.02; P=0.009). Conclusion: Post-irradiation SNHL at high frequencies in patients suffering from nasopharyngeal carcinoma is more common than that at low frequencies. The independent prognostic factors for development of SNHL at high frequencies are patient's age and follow-up time. But the role of preirradiation hearing level ,irradiation dose and chemotherapy including cisplatin are not conclusive and further research is needed. (authors)

  2. Irradiation Behavior and Post-Irradiation Examinations of an Acoustic Sensor Using a Piezoelectric Transducer

    International Nuclear Information System (INIS)

    Lambert, T.; Zacharie-Aubrun, I.; Hanifi, K.; Valot, Ch.; Fayette, L.; Rosenkantz, E.; Ferrandis, J.Y.; Tiratay, X.

    2013-06-01

    The development of advanced instrumentation for in-pile experiments in Material Testing Reactor constitutes a main goal for the improvement of the nuclear fuel behavior knowledge. In the framework of high burn-up fuel experiments under transient operating conditions, an innovative sensor based on acoustic method was developed by CEA and IES (Southern Electronic Institute).This sensor is used to determine the on-line composition of the gases located in fuel rodlet free volume and thus, allows calculating the molar fractions of fission gases and helium. The main principle of the composition determination by acoustic method consists in measuring the time of flight of an acoustic signal emitted and reflected in a specific cavity. A piezoelectric transducer, driven by a pulse generator, generates the acoustic wave in the cavity. The piezoelectric transducer is a PZT ceramic disk, mainly consisting of lead, zirconium and titanium. This acoustic method was tested with success during a first experiment called REMORA 3, and the results were used to differentiate helium and fission gas release kinetics under transient operating conditions. However, during the irradiation test, acoustic signal degradation was observed, mainly due to irradiation effect but also due to the increasing of the gas temperature. Despite this acoustic signal degradation, the time of flight measurements were carried out with good accuracy throughout the test, thanks to the development of a more efficient signal processing. After experiment, neutronic calculations were performed in order to determine neutron fluence at the level of the piezoelectric transducer. In order to have a better understanding of the acoustic sensor behavior under irradiation, Post Irradiation Examination program was done on piezoelectric transducer and on acoustic coupling material too. These examinations were also realized on a non-irradiated acoustic sensor built in the same conditions and with the same materials and the same

  3. Post-irradiation examination of the vipac fuel assemblies IFA-104 and IFA-203, irradiated in the Halden boiling water reactor

    International Nuclear Information System (INIS)

    Linde, A. van der; Lucas Luyckx, H.J.B.

    1976-11-01

    Two seven pin assemblies, IFA-104 and IFA-203, have been irradiated in the Halding Boiling Water Reactor. The Zircaloy clad pins contained vibrationally compacted, sharp edged UO 2 particles with smear densities of 84-88% theoretical density and a fuel stack length of about 1520 mm. The IFA-104 pins operated satisfactorily during approximately 240 effective full power days at an average linear heat rating of about 340 W/cm, and a peak rating of about 480 W/cm. Ingress of water via a pressure transducer into one of the IFA-203 pins necessitated the premature termination of the irradiation after approximately 30 effective full power days at an average rating of about 460 W/cm, and a peak rating of about 550 W/cm. One IFA-104 pin and two IFA-203 pins failed early. The primary cause of these failures has been sought in the oxidation reaction of the tantalum tube which protected the W/Re thermocouples with the surrounding UO 2 or with moisture in the fuel at temperatures in excess of approximately 1700degC. The fuel centre temperature and the internal gas pressure measurements during the beginning of lifetime and the results of the post-irradiation chemical and microscopic analysis on fuel pin cross-sections have been correlated with corresponding data calculated on a Gapcon-Thermal computer programme written for pellet fuel pins. Fairly good agreement could be achieved between the measured data on the vipac pins and the calculated data of a pellet pin. During the corrosion of the Zircaloy-2 cladding of the IFA-104 pins which were autoclaved in 400degC steam prior to the irradiation, relatively large amounts of H 2 entered the cladding from the D 2 O coolant side. With 0.66 mole% H 2 O in the D 2 O the calculated hydrogen uptake preference ratio was 33

  4. Protective Effect of Vitamin E against Gamma Radiation Injury in Mice Histological and Ultrastructural Studies

    International Nuclear Information System (INIS)

    Abu Nour, S.M.; Abd EI Azeem, M.G.

    2009-01-01

    Vitamin E has been shown to ameliorate the effect of ionising radiation. The present study was designed to study the effect of high dose of gamma-radiation on the intestinal tissue of mice and the protective effect of the natural antioxidant vitamin E; a slow acting free radical scavenger. 24 adult albino male mice were divided into 4 groups (6 animals each). The first group represents the control group. The second experimental group received orally daily doses of vitamin E (100 mg/ kg body wt for 15 days). The third experimental group were exposed to 7 Gy gamma-rays as a single dose, while the fourth experimental group received vitamin E in the same dose before being irradiated. All animals were scarified and jejunal specimens were processed and prepared for histological and ultrastructural study after one day post irradiation. The results suggested that gamma-radiation induced different histological changes in the intestine of irradiated animals. Degeneration of the intestinal cells and microvilli were seen by light microscopic examination. SEM electron microscope (SEM) revealed haemorrhagic ulcerating tissues. In addition, the mitochondria were markedly swollen and loss of cristae, thickness of the terminal web zone was seen by transmission electron microscope. On the contrary, in animals treated with vitamin E, the intestinal tissues revealed structure almost similar to the control group. We conclude that vitamin E had protective effects against gamma-radiation induced oxidative stress

  5. Protective effects of bacterial endotoxin in reconstruction of hematopoiesis after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wenzhong, Zhao; Renqian, Zhong [Second Military medical Coll., Shanghai, SH (China). Dept. of Radiation Medicine

    1989-06-01

    The mechanism of protective effects of bacterial endotoxin (ET) in reconstruction of hemopoiesis post-irradiation has been studied. The results showed that (1) in normal men, dogs, rabbits and rats, after im injection of typhobacterial endotoxin (ETt), the peripheral blood leucocytes (PBL) increased in number remarkably; (2) the injection of microdoses of ETt into hypothalamus of the rabbits and rats caused no obvious change in number of PBL, suggesting that there was neither regulation on the granulomacrophagopoiesis of the vegetative nervous center in hypothalamus nor the regulative effect of the hypothalamo-pituitary endocrine system. The curves of the stimulating factor (CSF) levels in serum after injection of bacillus coli endotoxin (ETc) were compared between the mouse bone marrow cell (BMC) membrane {sup 3}H-galactose incorporation method and the agar cellular colony culture technique. It was shown that they had obvious relationships with the dose-response curve of purified CSF-1. There was no effect on the incorporation value and colony number when ETc was added to culture well directly. The protective effects of the ETc-serum on the 8 Gy irradiated mice was realized by inducing GM-CSF and promoting the reconstruction of hematopoiesis.

  6. Available post-irradiation examination techniques at Romanian institute for nuclear research

    International Nuclear Information System (INIS)

    Parvan, Marcel; Sorescu, Antonius; Mincu, Marin; Uta, Octavian; Dobrin, Relu

    2005-01-01

    The Romanian Institute for Nuclear Research (INR) has a set of nuclear facilities consisting of TRIGA 14 MW(th) materials testing reactor and LEPI (Romanian acronym for post-irradiation examination laboratory) which enable to investigate the behaviour of the nuclear fuel and materials under various irradiation conditions. The available techniques of post-irradiation examination (PIE) and purposes of PIE for CANDU reactor fuel are as follows. 1) Visual inspection and photography by periscope: To examine the surface condition such as deposits, corrosion etc. 2) Eddy current testing: To verify the cladding integrity. 3) Profilometry and length measurement performed both before and after irradiation: To measure the parameters which highlight the dimensional changes i.e. diameter, length, diametral and axial sheath deformation, circumferential sheath ridging height, bow and ovality. 4) Gamma scanning and Tomography: To determine the burnup, axial and radial fission products activity distribution and to check for flux peaking and loading homogeneity. 5) Puncture test: To measure the pressure, volume and composition of fission gas and the inner free volume. 6) Optical microscopy: To highlight the structural changes and hydriding, to examine the condition of the fuel-sheath interface and to measure the oxide thickness and Vickers microhardness. 7) Mass spectrometry: To measure the burnup. 8) Tensile testing: To check the mechanical properties. So far, non-destructive and destructive post-irradiation examinations have been performed on a significant number of CANDU fuel rods (about 100) manufactured by INR and irradiated to different power histories in the INR 14 MW(th) TRIGA reactor. These examinations have been performed as part of the Romanian research programme for the manufacturing, development and safety of the CANDU fuel. The paper describes the PIE techniques and some results. (Author)

  7. Isothermal and isochronal annealing methodology to study post-irradiation temperature activated phenomena

    International Nuclear Information System (INIS)

    Chabrerie, C.; Autran, J.L.; Paillet, P.; Flament, O.; Leray, J.L.; Boudenot, J.C.

    1997-01-01

    In this work, the evolution of the oxide trapped charge has been modeled, to predict post-irradiation behavior for arbitrary anneal conditions (i.e., arbitrary temperature-time profiles). Using experimental data obtained from a single isochronal anneal, the method consists of calculating the evolution of the energy distribution of the oxide trapped charge, in the framework of a thermally activated charge detrapping model. This methodology is illustrated in this paper by the prediction of experimental isothermal data from isochronal measurements. The implications of these results to hardness assurance test methods are discussed

  8. 16-rod-bundle: Irradiation in the MZFR and post-irradiation examinations

    International Nuclear Information System (INIS)

    Manzel, R.

    1979-04-01

    In the course of the irradiation of a 16-rod prototype bundle, the basis has been established for the irradiation of experimental fuel assemblies containing full-length PWR fuel rods in standard positions of the MZFR. The prototype bundle was discharged after an irradiation time of 284 full power days and a burnup of 11400 MWd/tU. The overall performance of the prototype bundle was highly satisfactory. Detailed post-irradiation examinations confirmed the good conditions of bundle structures and fuel rods. (orig.) [de

  9. Post-irradiation treatment of human lymphocytes with spermidine reduced frequency of chromatid breaks

    International Nuclear Information System (INIS)

    Bocian, E.; Rosiek, O.; Ziemba-Zoltowska, B.

    1978-01-01

    Human lymphocyte cultures were X-irradiated with a single dose of 100 or 200 rad 46 h after phytohemagglutinin stimulation. In dose-fractionation experiments, 2h later the second dose was applied. All the cultures were harvested at 54 h after their initiation. In lymphocytes irradiated with a single dose of 200 rad, 2h post-irradiation contact with 10 -5 M exogeneous spermidine resulted in reduction of chromatid breaks by 34 %. Introduction of spermidine into culture medium for fractionation interval between the 2 doses of 100 rad reduced the frequency of chromatid breaks by 42 %. (author)

  10. Facilities for post-irradiation examination of experimental fuel elements at Chalk River Nuclear Laboratories

    International Nuclear Information System (INIS)

    Mizzan, E.; Chenier, R.J.

    1979-10-01

    Expansion of post-irradiation facilities at the Chalk River Nuclear Laboratories and steady improvement in hot-cell techniques and equipment are providing more support to Canada's reactor fuel development program. The hot-cell facility primarily used for examination of experimental fuels averages a quarterly throughput of 40 elements and 110 metallographic specimens. New developments in ultrasonic testing, metallographic sample preparation, active storage, active waste filtration, and fissile accountability are coming into use to increase the efficiency and safety of hot-cell operations. (author)

  11. Study on radiation protective effect of resveratrol and its molecular mechanism

    International Nuclear Information System (INIS)

    Lv Qiujun; Wen Liqing; Zhang Min; Guo Shaoming; Chen Yuanyuan; Wu Zuze

    2004-01-01

    Objective: To investigate radiation-protective effect of resveratrol and its molecular mechanism. Methods: Kunming mice were administered with resveratrol before 60 Co γ-irradiation. Thirty-day survival rate and the average life span of dead mice post-irradiation were observed. The apoptosis of spleen from irradiated mice was detected by FACS and in situ terminal labeling method. The effect of resveratrol on the activities of Caspase-3 and Caspase-8, and the expression levels of Bcl-2 and Fas were examined. Results: Administration with resveratrol resulted in increases of 30-day survival rate and prolongation of average life span of the dead mice. Apoptotic rate of spleen cells decreased, expression level of bcl-2 increased, the expression of Fas did not change, and the activities of Caspase-3 and Caspase-8 increased in spleen cells of irradiation groups. Conclusion: The results indicate that resveratrol has radiation-protective effect and its mechanism might be related with its suppression of apoptosis of radiation-sensitive cells

  12. Surgical treatments for post-irradiation intestinal injury in uterine cervix cancer patients

    International Nuclear Information System (INIS)

    Nozaki, Isao; Yokoyama, Nobuji; Takashima, Shigemitsu

    1997-01-01

    We examined 19 patients with post-irradiation intestinal injury in the uterine cervix cancer for 12 years between 1985 and 1996. We discuss the usefulness and complications of surgery, mainly colostomy. The patients aged from 36 to 80 (average age 61) were treated, and their disease states were 12 cases of rectovaginal fistula, 2 of small intestinal fisfula, 1 of rectum posterior membranous fistula, 3 of proctostenosis, and 14 of proctitis with hemorrhage (including duplication). Surgical methods used were 18 cases of colostomy (2 cases were treated under peritoneum mirror) and 2 of enterocolostomy (including duplication). Eleven out of 19 patients who underwent surgery are alive now. Generally the post-irradiation intestinal injury was intractable, and the method of treatments were limited due to the coexistence of various diseases. The colostomy is safe and less invasive. Therefore patients with uterine cervix cancer having various complications can obtain high quality of life (QOL) such as the improvement of anemia and/or the increase of digestion by the colostomy. (K.H.)

  13. Surgical treatments for post-irradiation intestinal injury in uterine cervix cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Nozaki, Isao; Yokoyama, Nobuji; Takashima, Shigemitsu [National Shikoku Cancer Center Hospital, Matsuyama, Ehime (Japan)

    1997-06-01

    We examined 19 patients with post-irradiation intestinal injury in the uterine cervix cancer for 12 years between 1985 and 1996. We discuss the usefulness and complications of surgery, mainly colostomy. The patients aged from 36 to 80 (average age 61) were treated, and their disease states were 12 cases of rectovaginal fistula, 2 of small intestinal fisfula, 1 of rectum posterior membranous fistula, 3 of proctostenosis, and 14 of proctitis with hemorrhage (including duplication). Surgical methods used were 18 cases of colostomy (2 cases were treated under peritoneum mirror) and 2 of enterocolostomy (including duplication). Eleven out of 19 patients who underwent surgery are alive now. Generally the post-irradiation intestinal injury was intractable, and the method of treatments were limited due to the coexistence of various diseases. The colostomy is safe and less invasive. Therefore patients with uterine cervix cancer having various complications can obtain high quality of life (QOL) such as the improvement of anemia and/or the increase of digestion by the colostomy. (K.H.)

  14. AGR-1 Compact 5-3-1 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Phil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ploger, Scott A. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-12-01

    The Advanced Gas Reactor (AGR) Fuel Development and Qualification Program was established to perform the requisite research and development on tristructural isotropic (TRISO) coated particle fuel to support deployment of a high-temperature gas-cooled reactor (HTGR). The work continues as part of the Advanced Reactor Technologies (ART) TRISO Fuel program. The overarching program goal is to provide a baseline fuel qualification data set to support licensing and operation of an HTGR. To achieve these goals, the program includes the elements of fuel fabrication, irradiation, post-irradiation examination (PIE) and safety testing, fuel performance, and fission product transport (INL 2015). A series of fuel irradiation experiments is being planned and conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). These experiments will provide data on fuel performance under irradiation, support fuel process development, qualify the fuel for normal operating conditions, provide irradiated fuel for safety testing, and support the development of fuel performance and fission product transport models. The first of these irradiation tests, designated AGR-1, began in the ATR in December 2006 and ended in November 2009. This experiment was conducted primarily to act as a shakedown test of the multicapsule test train design and provide early data on fuel performance for use in fuel fabrication process development. It also provided samples for post-irradiation safety testing, where fission product retention of the fuel at high temperatures will be experimentally measured. The capsule design and details of the AGR-1 experiment have been presented previously.

  15. Post-irradiation pericardial malignant mesothelioma with deletion of p16: a case report.

    Science.gov (United States)

    Naeini, Yalda B; Arcega, Ramir; Hirschowitz, Sharon; Rao, Nagesh; Xu, Haodong

    2018-02-01

    Malignant mesotheliomas are rather uncommon neoplasms associated primarily with asbestos exposure; however, they may also arise as second primary malignancies after radiation therapy, with a latency period of 15-25 years. Numerous studies have reported an association between pleural malignant mesothelioma and chest radiation performed for other malignancies; on the other hand, post-irradiation mesotheliomas of the pericardium have been reported in only a few published cases to date, and no homozygous deletion of 9p21 has been described in such cases. We report the case of a 48-year-old man with a history of Hodgkin's lymphoma and no prior asbestos exposure who developed pericardial malignant epithelioid mesothelioma. We further discuss the cytologic, histologic, immunophenotypic, and fluorescence in situ hybridization findings in this case. To our knowledge, this is the first well-documented case of post-radiation pericardial malignant mesothelioma showing homozygous deletion of 9p21. Homozygous deletion of 9p21, the locus harboring the p16 gene, is present in post-irradiation pericardial malignant mesothelioma.

  16. SU-E-T-222: Investigation of Pre and Post Irradiation Fading of the TLD100 Thermoluminescence Dosimetry for Photon Beams

    International Nuclear Information System (INIS)

    Sina, S; Sadeghi, M; Faghihi, R

    2014-01-01

    Purpose: The pre-irradiation and post-irradiation fading of the Thermoluminescense dosimeter signals were investigated in this study. Methods: Two groups of TLD chips with pre-determined ECC values were used in this study. The two groups were divided into 6 series, each composing of 5 TLD chips.The first group was used for pre-irradiation fading. 5 TLDs were exposed to a known amount of radiation from Cs-137 source, and were read out the next day. After seven days, the other 5 TLDs were exposed to the same amount of radiation and were read out after a day. The other series of 5 TLDs were also exposed after 7,19,28, 59, and 90 days, and were read out a day after irradiation. The loss in TLD signal were obtained for all the above cases. The second group, was used for postirradiation fading. All the TLDs of this group were exposed to a known amount of radiation from Cs-137 source. The 6 series composed of 5 TLDs were read out after 1,7,19,28,59, and 90 days. The above-mentioned procedures for obtaining pre-irradiation, and post-irradiation fading were performed for three storage temperatures (25°C, 4°C, and −18°C). Results: According to the results obtained in this study, in case of pre-irradiation fading study, the signal losses after 90 days are 12%, 24%, and 17% for 25°C, 4°C, and −18°C respectively. In case of post-irradiation fading study, the sensitivity losses after 90 days are 25%, 216%, and 20% for 25°C, 4°C, and −18°C respectively. Conclusion: The results indicate that the optimized time between exposing and reading out, and also the optimized time between annealing and exposing is 1 day.The reduction of Storage temperature will reduce the post-irradiation fading, While temperature reduction does not have any effect on pre-irradiation fading

  17. SU-E-T-222: Investigation of Pre and Post Irradiation Fading of the TLD100 Thermoluminescence Dosimetry for Photon Beams

    Energy Technology Data Exchange (ETDEWEB)

    Sina, S [Radiation Research Center, Shiraz University, Shiraz (Iran, Islamic Republic of); Sadeghi, M [Nuclear Engineering department, Shiraz university, Shiraz (Iran, Islamic Republic of); Faghihi, R [Radiation Research Center, Shiraz University, Shiraz (Iran, Islamic Republic of); Nuclear Engineering department, Shiraz university, Shiraz (Iran, Islamic Republic of)

    2014-06-01

    Purpose: The pre-irradiation and post-irradiation fading of the Thermoluminescense dosimeter signals were investigated in this study. Methods: Two groups of TLD chips with pre-determined ECC values were used in this study. The two groups were divided into 6 series, each composing of 5 TLD chips.The first group was used for pre-irradiation fading. 5 TLDs were exposed to a known amount of radiation from Cs-137 source, and were read out the next day. After seven days, the other 5 TLDs were exposed to the same amount of radiation and were read out after a day. The other series of 5 TLDs were also exposed after 7,19,28, 59, and 90 days, and were read out a day after irradiation. The loss in TLD signal were obtained for all the above cases. The second group, was used for postirradiation fading. All the TLDs of this group were exposed to a known amount of radiation from Cs-137 source. The 6 series composed of 5 TLDs were read out after 1,7,19,28,59, and 90 days. The above-mentioned procedures for obtaining pre-irradiation, and post-irradiation fading were performed for three storage temperatures (25°C, 4°C, and −18°C). Results: According to the results obtained in this study, in case of pre-irradiation fading study, the signal losses after 90 days are 12%, 24%, and 17% for 25°C, 4°C, and −18°C respectively. In case of post-irradiation fading study, the sensitivity losses after 90 days are 25%, 216%, and 20% for 25°C, 4°C, and −18°C respectively. Conclusion: The results indicate that the optimized time between exposing and reading out, and also the optimized time between annealing and exposing is 1 day.The reduction of Storage temperature will reduce the post-irradiation fading, While temperature reduction does not have any effect on pre-irradiation fading.

  18. Evaluation of the protective and curative role of curcumin and venoruton against biological effects of radiation

    International Nuclear Information System (INIS)

    El-Sayed, N.M.

    2006-01-01

    Curcumin (diferuloyl methane) and venoruton [O-(beta-hydroxyethyl)-rutosides] are powerful antioxidants and are important in protecting the cells from damage. The present study aims to evaluate the role of curcumin alone and curcumin with venoruton on radiation-induced changes in male rats exposed to a dose of 5 Gy gamma irradiation. Experimental analyses were performed 1, 7 and 14 days post-irradiation in all animal groups. Exposure to ionizing radiation resulted in decrease in glutathione content and SOD, G6PD and CPK activities and increase in lactate dehydrogenase and GOT activities and creatinine level. The results obtained showed that treatment of rats with olive oil pre and post-irradiation has significantly minimized radiation-induced changes. Curcumin dissolved in olive oil pre and post-irradiation significantly improved the radiation-induced changes while administration of venoruton with curcumin in olive oil provided a better amelioration. It could be concluded that, curcumin in olive oil plus venoruton showed an obvious protective and curative role against the hazards of gamma radiation in male rats

  19. Pre- and post-irradiation characterization and properties measurements of ZrC coated surrogate TRISO particles

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevamurthy, Gokul [ORNL; Katoh, Yutai [ORNL; Hunn, John D [ORNL; Snead, Lance Lewis [ORNL

    2010-09-01

    Zirconium carbide is a candidate to either replace or supplement silicon carbide as a coating material in TRISO fuel particles for high temperature gas-cooled reactor fuels. Six sets of ZrC coated surrogate microsphere samples, fabricated by the Japan Atomic Energy Agency using the fluidized bed chemical vapor deposition method, were irradiated in the High Flux Isotope Reactor at the Oak Ridge National Laboratory. These developmental samples available for the irradiation experiment were in conditions of either as-fabricated coated particles or particles that had been heat-treated to simulate the fuel compacting process. Five sets of samples were composed of nominally stoichiometric compositions, with the sixth being richer in carbon (C/Zr = 1.4). The samples were irradiated at 800 and 1250 C with fast neutron fluences of 2 and 6 dpa. Post-irradiation, the samples were retrieved from the irradiation capsules followed by microstructural examination performed at the Oak Ridge National Laboratory's Low Activation Materials Development and Analysis Laboratory. This work was supported by the US Department of Energy Office of Nuclear Energy's Advanced Gas Reactor program as part of International Nuclear Energy Research Initiative collaboration with Japan. This report includes progress from that INERI collaboration, as well as results of some follow-up examination of the irradiated specimens. Post-irradiation examination items included microstructural characterization, and nanoindentation hardness/modulus measurements. The examinations revealed grain size enhancement and softening as the primary effects of both heat-treatment and irradiation in stoichiometric ZrC with a non-layered, homogeneous grain structure, raising serious concerns on the mechanical suitability of these particular developmental coatings as a replacement for SiC in TRISO fuel. Samples with either free carbon or carbon-rich layers dispersed in the ZrC coatings experienced negligible grain size

  20. Protective effect of atorvastatin on radiation-induced endothelial cell injury

    Energy Technology Data Exchange (ETDEWEB)

    Xinze, Ran; Huaien, Zheng; Fengchao, Wang; Xi, Ran; Aiping, Wang; Jing, Han; Yanqi, Zhang; Jun, Chen [Institute of Combined Injury, State Key Laboratory of Trauma, Burns and Combined Injury, College of Preventive Medicine, Third Military Medical University, Chongqing (China)

    2009-04-15

    Objective: To explore the protective effect of atorvastatin on irradiated endothelium and the thrombomodulin (TM) expression. Methods: Cultured human coronary artery endothelial cells (HCAEC) and human umbilical vein endothelial cells (HUVEC) were treated by atorvastatin at the final concentration of 10 {mu}mol/ml for 10 min, and then irradiated with 2 and 25 Gy. Cell cycles status and TM expression were quantitatively measured by flow cytometry 24 hours after irradiation. Protein C activation in endothelial cells was also assessod. Results: After administration with atorvastatin for 24 h, the TM expression increased by 77%, 59% and 61% in normal control group, 2 Gy group and 25 Gy group, respectively (t=27.395, 26.420, 58.065; P=0.000). The protein C levels decreased by 23% and 34% compared with the normal group post-irradiation to 2 and 25 Gy, but increased by 79% and 76% compared with the irradiated control group after administration with atorvastatin. The rates of cell apoptosis decreased by 6% and 16% in 2 Gy and 25 Gy groups, respectively after administration with atorvastatin for 24 h (t=4.178, 17.863; P=0.000). Conclusions: Atorva statin can protect endothelia cell from irradiation-induced apeptosis by increasing TM expression and protein C activation. (authors)

  1. Protective effect of atorvastatin on radiation-induced endothelial cell injury

    International Nuclear Information System (INIS)

    Ran Xinze; Zheng Huaien; Wang Fengchao; Ran Xi; Wang Aiping; Han Jing; Zhang Yanqi; Chen Jun

    2009-01-01

    Objective: To explore the protective effect of atorvastatin on irradiated endothelium and the thrombomodulin (TM) expression. Methods: Cultured human coronary artery endothelial cells (HCAEC) and human umbilical vein endothelial cells (HUVEC) were treated by atorvastatin at the final concentration of 10 μmol/ml for 10 min, and then irradiated with 2 and 25 Gy. Cell cycles status and TM expression were quantitatively measured by flow cytometry 24 hours after irradiation. Protein C activation in endothelial cells was also assessod. Results: After administration with atorvastatin for 24 h, the TM expression increased by 77%, 59% and 61% in normal control group, 2 Gy group and 25 Gy group, respectively (t=27.395, 26.420, 58.065; P=0.000). The protein C levels decreased by 23% and 34% compared with the normal group post-irradiation to 2 and 25 Gy, but increased by 79% and 76% compared with the irradiated control group after administration with atorvastatin. The rates of cell apoptosis decreased by 6% and 16% in 2 Gy and 25 Gy groups, respectively after administration with atorvastatin for 24 h (t=4.178, 17.863; P=0.000). Conclusions: Atorva statin can protect endothelia cell from irradiation-induced apeptosis by increasing TM expression and protein C activation. (authors)

  2. Lunar electrostatic effects and protection

    International Nuclear Information System (INIS)

    Sun, Yongwei; Yuan, Qingyun; Xiong, Jiuliang

    2013-01-01

    The space environment and features on the moon surface are factors in strong electrostatic electrification. Static electricity will be produced in upon friction between lunar soil and detectors or astronauts on the lunar surface. Lunar electrostatic environment effects from lunar exploration equipment are very harmful. Lunar dust with electrostatic charge may enter the equipment or even cover the instruments. It can affect the normal performance of moon detectors. Owing to the huge environmental differences between the moon and the earth, the electrostatic protection technology on the earth can not be applied. In this paper, we review the electrostatic characteristics of lunar dust, its effects on aerospace equipment and moon static elimination technologies. It was concluded that the effect of charged lunar dust on detectors and astronauts should be completely researched as soon as possible.

  3. Post-irradiation studies on knock-out and pseudo-recoil releases of fission products from fissioning UO2

    International Nuclear Information System (INIS)

    Yamagishi, S.; Tanifuji, T.

    1976-01-01

    By using post-irradiation techniques, in-pile releases of 133 Xe, sup(85m)Kr, 88 Kr, 87 Kr and 138 Xe from UO 2 fissioning at low temperatures below about 200 0 C are studied: these are analyzed into a time-dependent knock-out and time-independent pseudo-recoil releases. For the latter, a 'self knock-out' mechanism is proposed: when a fission fragment loses thoroughly its energy near the UO 2 surface and stops there, it will knock out the surface substances and accordingly the fragment (i.e. the fission product) will be released. The effective thickness of the layer where the self knock-out occurs is found to be approximately 7A. As for the knock-out release, the following is estimated from its dependence on various factors: the knock-out release of fission products occurs from the surface layer with the effective thickness of approximately 20A: the shape of UO 2 matrix knocked out by one fission fragment passing through the surface is equivalent to a cylinder approximately 32A diameter by approximately 27A thick, (i.e. the knock-out coefficient for UO 2 is approximately 660 uranium atoms per knock-out event). On the basis of the above estimations, the conclusions derived from the past in-pile studies of fission gas releases are evaluated. (Auth.)

  4. The post-irradiated examination of CANDU type fuel irradiated in the Institute for Nuclear Research TRIGA reactor

    International Nuclear Information System (INIS)

    Tuturici, I.L.; Parvan, M.; Dobrin, R.; Popov, M.; Radulescu, R.; Toma, V.

    1995-01-01

    This post-irradiation examination work has been done under the Research Contract No. 7756/RB, concluded between the International Atomic Energy Agency and the Institute for Nuclear Research. The paper contains a general description of the INR post-irradiation facility and methods and the relevant post-irradiation examination results obtained from an irradiated experimental CANDU type fuel element designed, manufactured and tested by INR in a power ramp test in the 100 kW Pressurised Water Irradiation Loop of the TRIGA 14 MW(th) Reactor. The irradiation experiment consisted in testing an assembly of six fuel elements, designed to reach a bumup of ∼ 200 MWh/kgU, with typical CANDU linear power and ramp rate. (author)

  5. Chemical protection against radiation effects on Serum transaminase and the levels of glutamic and pyruvic acids following gamma irradiation of rats

    International Nuclear Information System (INIS)

    Mahdy, A.M.; EL-Kashef, H.S.

    1988-01-01

    The present study been carried out to evaluate the radioprotective efficiency of urea and vitamin E for protecting certain enzymatic systems from deleterious radiation effects. The activities of serum transaminase; aspartate aminotransferase (A S T) and alanine aminotransferase (A L T); as well as their relative substrates; glutamic and pyruvic acid levels; were selected for this study. The results indicated that whole body gamma irradiation at the dose of 7 Gy caused an evident elevation in the activities of both A S T and A L T and in the level of pyruvic acid at the experiment period (first,third,seventh and tenth days post irradiation). On the other hand the free glutamic acid level decreased at all post irradiation days. The variation in both enzymatic activities, pyruvic and glutamic acid levels became less pronounced in rats treated with either urea or vitamin E as chemical radioprotectors before whole body gamma irradiation. The results showed that the two agents are good radioprotectors, with respect to these parameters under investigation

  6. Fuels and materials research under the high neutron fluence using a fast reactor Joyo and post-irradiation examination facilities

    International Nuclear Information System (INIS)

    Soga, Tomonori; Ito, Chikara; Aoyama, Takafumi; Suzuki, Soju

    2009-01-01

    The experimental fast reactor Joyo at Oarai Research and Development Center (ORDC) of Japan Atomic Energy Agency (JAEA) is Japan's sodium-cooled fast reactor (FR). In 2003, this reactor's upgrade to the 140MWt MK-III core was completed to increase the irradiation testing capability. The MK-III core provides the fast neutron flux of 4.0x10 15 n/cm 2 s as an irradiation test bed for improving the fuels and material of FR in Japan. Three post-irradiation examination (PIE) facilities named FMF, MMF and AGF related to Joyo are in ORDC. Irradiated subassemblies and core components are carried into the FMF (Fuel Monitoring Facility) and conducted nondestructive examinations. Each subassembly is disassembled to conduct some destructive examinations and to prepare the fuel and material samples for further detailed examinations. Fuel samples are sent to the AGF (Alpha-Gamma Facility), and material samples are sent to the MMF (Materials Monitoring Facility). These overall and elaborate data provided by PIE contribute to investigate the irradiation effect and behavior of fuels and materials. This facility complex is indispensable to promote the R and D of FR in Japan. And, the function and technology of irradiation test and PIE enable to contribute to the R and D of innovative fission or fusion reactor material which will be required to use under the high neutron exposure. (author)

  7. Protective Effect of Anthocyanins from Lingonberry on Radiation-induced Damages

    Directory of Open Access Journals (Sweden)

    Shuang-Qi Tian

    2012-12-01

    Full Text Available There is a growing concern about the serious harm of radioactive materials, which are widely used in energy production, scientific research, medicine, industry and other areas. In recent years, owing to the great side effects of anti-radiation drugs, research on the radiation protectants has gradually expanded from the previous chemicals to the use of natural anti-radiation drugs and functional foods. Some reports have confirmed that anthocyanins are good antioxidants, which can effectively eliminate free radicals, but studies on the immunoregulatory and anti-radiation effects of anthocyanins from lingonberry (ALB are less reported. In this experiment, mice were given orally once daily for 14 consecutive days before exposure to 6 Gy of gamma-radiation and were sacrificed on the 7th day post-irradiation. The results showed that the selected dose of extract did not lead to acute toxicity in mice; while groups given anthocyanins orally were significantly better than radiation control group according to blood analysis; pretreatment of anthocyanins significantly (p < 0.05 enhanced the thymus and spleen indices and spleen cell survival compared to the irradiation control group. Pretreatment with anthocyanins before irradiation significantly reduced the numbers of micronuclei (MN in bone marrow polychromatic erythrocytes (PCEs. These findings indicate that anthocyanins have immunostimulatory potential against immunosuppression induced by the radiation.

  8. Post-irradiation dietary vitamin E does not affect the development of radiation-induced lung damage in rats

    International Nuclear Information System (INIS)

    Wiegman, Erwin M.; Gameren, Mieke M. van; Kampinga, Harm H.; Szabo, Ben G.; Coppes, Rob P.

    2004-01-01

    The purpose of this study was to investigate whether application of post-irradiation vitamin E, an anti-oxidant, could prevent the development of radiation induced lung damage. Wistar rats were given vitamin E enriched or vitamin E deprived food starting from 4 weeks after 18 Gy single dose irradiation of the right thorax. Neither breathing frequencies nor CT density measurements revealed differences between the groups. It is concluded that post-irradiation vitamin E does not influence radiation-induced fibrosis to the lung

  9. Possible curative role of the anti psychotic drug fluphenazine against post-irradiation injury in rats

    International Nuclear Information System (INIS)

    Hassan, S.H.M.; Abu-Ghadeer, A.R.M.; Osman, S.A.A.; Roushdy, H.M.

    1986-01-01

    In the present study, investigation of the possible curative role of the anti psychotic agent ''fluphenazine'' against post irradiation injury of certain sensitive biological targets has been studied in rats. Such investigation includes evaluation of the haematological levels, liver function as manifested by levels of relevant serum enzymes and kidney function as reflected by level of serum creatinine and rate of urine creatinine clearance. Data of the present study indicated that fractionated whole body gamma-irradiation resulted in haematological disorders, significant elevation in serum enzyme activities of both serum glutamic pyruvic transaminase (SGPT) and serum alkaline phosphatase (SALKPH.), significant decrease in serum cholinesterase (SCHE) activity and a significant increase in serum creatinine accompanied by a significant decrease in creatinine clearance. 4 figs., 4 tabs

  10. AECL hot-cell facilities and post-irradiation examination services

    International Nuclear Information System (INIS)

    Schankula, M.H.; Plaice, E.L.; Woodworth, L.G.

    1995-01-01

    This paper presents an overview of the post-irradiation examination (PIE) services available at AECL's hot-cell facilities (HCF). The HCFs are used primarily to provide PIE support for operating CANDU power reactors in Canada and abroad, and for the examination of experimental fuel bundles and core components irradiated in research reactors at the Chalk River Laboratories (CRL) and off-shore. A variety of examinations and analysis are performed ranging from non-destructive visual and dimensional inspections to detailed optical and scanning electron microscopic examinations. Several hot cells are dedicated to mechanical property testing of structural materials and to determine the fitness-for-service of reactor core components. Facility upgrades and the development of innovative examination techniques continue to improve AECL's PIE capabilities. (author)

  11. Post-irradiation vasculopathy of intracranial major arteries in children; Report of two cases

    Energy Technology Data Exchange (ETDEWEB)

    Nishizawa, Shigeru; Ryu, Hiroshi; Yokoyama, Tetsuo; Ninchoji, Toshiaki; Shimoyama, Ichiro; Yamamoto, Seiji; Uemura, Kenichi [Hamamatsu Univ. School of Medicine, Shizuoka (Japan)

    1991-06-01

    We report two rare cases of post-irradiation vasculopathy of intracranial major arteries in children. A 13-year-old girl suffered from transient right hemiparesis 1 year after irradiation for suprasellar germinoma. Left carotid angiograms revealed marked stenoses of the intracranial internal carotid, middle cerebral, and anterior cerebral arteries, which were previously normal, and moyamoya vessels. A 2.5-year-old girl underwent internal irradiation with {sup 198}Au colloid for cystic craniopharyngioma. At the age of 10 years, she suddenly became unconscious after vomiting. Computed tomographic scans showed a right frontal intracerebral hematoma. Right carotid angiograms disclosed complete obstruction of the intracranial internal carotid, middle cerebral, and anterior cerebral arteries and moyamoya vessels, previously not present. The danger of radiation therapy causing occlusive vasculopathy in small and major cerebral arteries in children is emphasized. To prevent permanent ischemic neurological deficits, vasculopathy should be treated either medically or surgically as early as possible. (author).

  12. AECL hot-cell facilities and post-irradiation examination services

    International Nuclear Information System (INIS)

    Schankula, M.H.; Plaice, E.L.; Woodworth, L.G.

    1998-04-01

    This paper presents an overview of the post-irradiation examination (PIE) services available at AECL's hot-cell facilities (HCF). The HCFs are used primarily to provide PIE support for operating CANDU power reactors in Canada and abroad, and for the examination of experimental fuel bundles and core components irradiated in research reactors at the Chalk River Laboratories (CRL) and off-shore. A variety of examinations and analyses are performed ranging from non-destructive visual and dimensional inspections to detailed optical and scanning electron microscopic examinations. Several hot cells are dedicated to mechanical property testing of structural materials and to determine the fitness-for-service of reactor core components. Facility upgrades and the development of innovative examination techniques continue to improve AECL's PIE capabilities. (author)

  13. Development status of post irradiation examination techniques at the JMTR Hot Laboratory

    International Nuclear Information System (INIS)

    Ohmi, M.; Ohsawa, K.; Nakagawa, T.; Umino, A.; Shimizu, M.; Satoh, H.; Oyamada, R.

    1992-01-01

    Hot laboratory at Oarai Research Establishment was founded to examine the objects mainly irradiated at JMTR (Japan Materials Testing Reactor) and has been operated since 1971. A wide variety of post-irradiation examinations (PIE) is available using the hot laboratory. Continuous efforts are made to develop new PIE techniques to accommodate the user's requirements. The following are main techniques recently developed in the hot laboratory; 1. Remote capsule assembly including remote weld of irradiated objects for reirradiation in JMTR. 2. Fracture toughness tests of reactor component materials. 3. Creep tests of heat resistance alloys in high temperature conditions. 4. Tests of irradiation assisted stress corrosion cracking (IASCC). 5. Examination techniques of miniaturized test specimens. This report describes an outline of the hot laboratory with main emphasis on the new PIE techniques. (author)

  14. Study on "1"4C content in post-irradiation graphite spheres of HTR-10

    International Nuclear Information System (INIS)

    Wang Shouang; Pi Yue; Xie Feng; Li Hong; Cao Jianzhu

    2014-01-01

    Since the production mechanism of the "1"4C in spherical fuel elements was similar to that of fuel-free graphite spheres, in order to obtain the amount of "1"4C in fuel elements and graphite spheres of HTR-10, the production mechanism of the "1"4C in graphite spheres was studied. The production sources of the "1"4C in graphite spheres and fuel elements were summarized, the amount of "1"4C in the post-irradiation graphite spheres was calculated, the decomposition techniques of graphite spheres were compared, and experimental methods for decomposing the graphite spheres and preparing the "1"4C sample were proposed. The results can lay the foundation for further experimental research and provide theoretical calculations for comparison. (authors)

  15. Post-irradiation repairing processes of glucose-6-phosphate dehydrogenase and catalase from Hansenula Polymorpha yeast

    International Nuclear Information System (INIS)

    Postolache, Carmen; Postolache, Cristian; Dinu, Diana; Dinischiotu, Anca; Sahini, Victor Emanuel

    2002-01-01

    The post-irradiation repairing mechanisms of two Hansenula Polymorpha yeast enzymes, glucose-6-phosphate dehydrogenase and catalase, were studied. The kinetic parameters of the selected enzymes were investigated over one month since the moment of γ-irradiation with different doses in the presence of oxygen. Dose dependent decrease of initial reaction rates was noticed for both enzymes. Small variation of initial reaction rate was recorded for glucose-6-phosphate dehydrogenase over one month, with a decreasing tendency. No significant electrophoretic changes of molecular forms of this enzyme were observed after irradiation. Continuous strong decrease of catalase activity was evident for the first 20 days after irradiation. Partial recovery process of the catalytic activity was revealed by this study. (authors)

  16. Post-Irradiation Non-Destructive Analyses of the AFIP-7 Experiment

    Science.gov (United States)

    Williams, W. J.; Robinson, A. B.; Rabin, B. H.

    2017-12-01

    This article reports the results and interpretation of post-irradiation non-destructive examinations performed on four curved full-size fuel plates that comprise the AFIP-7 experiment. These fuel plates, having a U-10 wt.%Mo monolithic design, were irradiated under moderate operating conditions in the Advanced Test Reactor to assess fuel performance for geometries that are prototypic of research reactor fuel assemblies. Non-destructive examinations include visual examination, neutron radiography, profilometry, and precision gamma scanning. This article evaluates the qualitative and quantitative data taken for each plate, compares corresponding data sets, and presents the results of swelling analyses. These characterization results demonstrate that the fuel meets established irradiation performance requirements for mechanical integrity, geometric stability, and stable and predictable behavior.

  17. Post-irradiation brain-necrosis resulting in apoplexia and death after 33 years of irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, A [Foevarosi Laszlo Korhaz, Budapest (Hungary). Korbonctani es Korszoevettani Oszt.

    1980-04-01

    A case of post-irradiation brain-necrosis resulting in apoplexia of the cerebellum after 33 years of irradiation (19984 r.) of a presumptive cerebellar tumour is reported. The pathohistologic study revealed symptoms of the ''late'' damage and the vascular changes appeared to be the most prominent. The thickening of the vessel walls, hyperplasia of collagen fibres and deposition of calcium in the media, were the most characteristic lesions revealed. In some of the small vessels isolated calcification of the media was observed. It seems most probable that in the development of apoplexia vascular alterations could play an important role. In the available literature no report has been found on a similarly long interval elapsing between the irradiation and death.

  18. Post-irradiation brain-necrosis resulting in apoplexia and death after 33 years of irradiation

    International Nuclear Information System (INIS)

    Froehlich, A.

    1980-01-01

    A case of post-irradiation brain-necrosis resulting in apoplexia of the cerebellum after 33 years of irradiation (19984 r.) of a presumptive cerebellar tumour is reported. The pathohistologic study revealed symptoms of the ''late'' damage and the vascular changes appeared to be the most prominent. The thickening of the vessel walls, hyperplasia of collagen fibres and deposition of calcium in the media, were the most characteristic lesions revealed. In some of the small vessels isolated calcification of the media was observed. It seems most probable that in the development of apoplexia vascular alterations could play an important role. In the available literature no report has been found on a similarly long interval elapsing between the irradiation and death. (author)

  19. A comparative study of post-irradiation growth kinetics of spheroids and monolayers

    International Nuclear Information System (INIS)

    Dertinger, J.; Luecke-Huhle, C.

    1975-01-01

    Post-irradiation growth kinetics of γ-irradiated spheroid and monolayer cells in exponential growth phase was investigated by means of dose-response curves based on cell counts after specified time intervals following irradiation. A mathematical model of cell-growth after irradiation was fitted to these curves. The model parameters (related to division delay and growth of non-surviving cells) obtained from this analysis consistently indicated increasing resistance to sub-lethal damage of cells cultured as multicellular spheroids under conditions of increasing three-dimensional contact. In contrast, no indication of an increased radiation-resistance was found with cells cultured on a substratum under a variety of conditions. (author)

  20. Analysis of recent post irradiation tests by Japanese and French burnup analysis code systems

    International Nuclear Information System (INIS)

    Iwasaki, Tomohiko; Hiraizumi, Hiroaki; Youinou, Gilles

    2002-01-01

    Benchmark problem based on Japanese Post Irradiation Experiment (PIE) data was analyzed by Japanese burnup analysis code and French one under the cooperative research program between the Japanese University Association (JUA) in Japan and Commissariat a l'Enegie Atomique (CEA) in France. Significant discrepancies over 10% were found between the Japanese and French results for 238 Pu, 243 Am, 244 Cm, 125 Sb, 154 Eu, 134 Cs and 144 Ce. It is supposed that the difference of C/E for 243 Am and 244 Cm between Japanese results and French ones is due to the (n,gamma) reaction of 242m Am. For 125 Sb and 154 Eu, the C/E values are improved by using new cross section and fission yield libraries. (author)

  1. AGR-1 Compact 1-3-1 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-12-01

    The Advanced Gas Reactor (AGR) Fuel Development and Qualification Program was established to perform the requisite research and development on tristructural isotropic (TRISO) coated particle fuel to support deployment of a high-temperature gas-cooled reactor (HTGR). The work continues as part of the Advanced Reactor Technologies (ART) TRISO Fuel program. The overarching program goal is to provide a baseline fuel qualification data set to support licensing and operation of an HTGR. To achieve these goals, the program includes the elements of fuel fabrication, irradiation, post-irradiation examination (PIE) and safety testing, fuel performance modeling, and fission product transport (INL 2015). A series of fuel irradiation experiments is being planned and conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). These experiments will provide data on fuel performance under irradiation, support fuel process development, qualify the fuel for normal operating conditions, provide irradiated fuel for safety testing, and support the development of fuel performance and fission product transport models. The first of these irradiation tests, designated AGR-1, began in the ATR in December 2006 and ended in November 2009. This experiment was conducted primarily to act as a shakedown test of the multicapsule test train design and provide early data on fuel performance for use in fuel fabrication process development. It also provided samples for post-irradiation safety testing, where fission product retention of the fuel at high temperatures will be experimentally measured. The capsule design and details of the AGR-1 experiment have been presented previously (Grover, Petti, and Maki 2010, Maki 2009).

  2. Welfare Effects of Employment Protection

    NARCIS (Netherlands)

    Belot, M.V.K.; Boone, J.; van Ours, J.C.

    2002-01-01

    Employment protection is often related to costs incurred by the firms when they hire a worker.The stability of the employment relationship, enhanced by employment protection, is also favorable to the productivity of the job.We analyze employment protection focusing on this trade-off between

  3. Post-irradiation dietary vitamin E does not affect the development of radiation-induced lung damage in rats

    NARCIS (Netherlands)

    Wiegman, EA; van Gameren, MA; Kampinga, HH; Szabo, BG; Coppes, RP

    The purpose of this study was to investigate whether application of post-irradiation vitamin E, an anti-oxidant, could prevent the development of radiation induced lung damage. Wistar rats were given vitamin E enriched or vitamin E deprived food starting from 4 weeks after 18 Gy single dose

  4. State of the VVER-1000 spent U-Gd fuel rods based on the results of post-irradiation examinations

    International Nuclear Information System (INIS)

    Shevlyakov, G.; Zvir, E.; Strozhuk, A.; Polenok, V.; Sidorenko, O.; Volkova, I.; Nikitin, O.

    2015-01-01

    The present paper is devoted to post-irradiation examinations (PIE) of U-Gd fuel rods with different geometry of the fuel pellets irradiated as part of the VVER-1000 fuel assembly. As evidenced by their PIE data, they did not exhaust their service life based on the main parameters (geometrical dimensions, corrosion state, and release of fission product gases). (author)

  5. Microstructure and mechanical properties of neutron irradiated OFHC-copper before and after post-irradiation annealing

    DEFF Research Database (Denmark)

    Singh, B.N.; Edwards, D.J.; Toft, P.

    2001-01-01

    of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates theproblem of yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade induced source hardening (CISH) and the dispersed...

  6. Gonad protective effect of radiation protective apron in chest radiography

    International Nuclear Information System (INIS)

    Hashimoto, Masatoshi; Kato, Hideyuki; Fujibuchi, Toshiou; Ochi, Shigehiro; Morita, Fuminori

    2004-01-01

    Depending on the facility, a radiation protective apron (protector) is used to protect the gonad from radiation exposure in chest radiography. To determine the necessity of using a protector during chest radiography, we measured the effect of the protector on the gonad in this study. First, using a human body phantom, we measured the absorbed dose of the female gonad with and without the protector, using a thermoluminescence dosimeter (TLD), and confirmed its protective effect. Using the protector, the absorbed dose was reduced to 28±2% and 39±4% for field sizes of 14 x 17 inch and 14 x 14 inch, respectively. Next, we used Monte Carlo simulation and confirmed, not only the validity of the actual measurement values, but also the fact that the influence of radiation on the absorbed dose of the gonad was mostly from scattered radiation from inside the body for the 14 x 17 inch field size, and also from the X-ray tube for the 14 x 14 inch field size. Although a certain protective effect is achieved by using the protector, the radiation dose to the gonad is only a few μGy even without a protector. Thus, the risk of a genetic effect would be as small as 10 -8 . Given that acceptable risk is below 10 -6 , we conclude the use of a radiation protective apron is not necessary for diagnostic chest radiography. (author)

  7. [Gonad protective effect of radiation protective apron in chest radiography].

    Science.gov (United States)

    Hashimoto, Masatoshi; Kato, Hideyuki; Fujibuchi, Toshiou; Ochi, Shigehiro; Morita, Fuminori

    2004-12-01

    Depending on the facility, a radiation protective apron (protector) is used to protect the gonad from radiation exposure in chest radiography. To determine the necessity of using a protector during chest radiography, we measured the effect of the protector on the gonad in this study. First, using a human body phantom, we measured the absorbed dose of the female gonad with and without the protector, using a thermoluminescence dosimeter (TLD), and confirmed its protective effect. Using the protector, the absorbed dose was reduced to 28+/-2% and 39+/-4% for field sizes of 14 x 17 inch and 14 x 14 inch, respectively. Next, we used Monte Carlo simulation and confirmed, not only the validity of the actual measurement values, but also the fact that the influence of radiation on the absorbed dose of the gonad was mostly from scattered radiation from inside the body for the 14 x 17 inch field size, and also from the X-ray tube for the 14 x 14 inch field size. Although a certain protective effect is achieved by using the protector, the radiation dose to the gonad is only a few microGy even without a protector. Thus, the risk of a genetic effect would be as small as 10(-8). Given that acceptable risk is below 10(-6), we conclude the use of a radiation protective apron is not necessary for diagnostic chest radiography.

  8. Pre- and post-irradiation properties of copper alloys at 250 deg. C following bonding and bakeout thermal cycles

    International Nuclear Information System (INIS)

    Singh, B.N.; Edwards, D.J.; Eldrup, M.; Toft, P.

    1997-01-01

    Screening experiments were carried out to investigate the effect of bonding and bakeout thermal cycles on microstructure, mechanical properties and electrical resistivity of the oxide dispersion strengthened (GlidCop, CuAl-25) and the precipitation hardened (CuCrZr, CuNiBe) copper alloys. Tensile specimens of CuCrZr and CuNiBe alloys were given various heat treatments corresponding to solution anneal, prime-ageing, and bonding thermal treatment followed by re-ageing and the reactor bakeout treatment at 350 deg. C for 100 h. Tensile specimens of CuAl-25 were given the heat treatment corresponding to the bonding thermal cycle. A number of heat treated specimens were neuron irradiated at 250 deg. C to a dose level of ∼ 0.3 dpa in the DR-3 reactor at Risoe. Both unirradiated and irradiated specimens with various heat treatments were tensile tested at 250 deg. C. The microstructure and electrical resistivity of these specimens were determined in the unirradiated as well as irradiated conditions. The post-deformation microstructure of the irradiated specimens was also investigated. The fracture surfaces of both unirradiated and irradiated specimens were examined. Results of these investigations are reported in the present report. The main effect of the bonding thermal cycle heat treatment was a slight decrease in strength of CuCrZr and CuNiBe alloys. The strength of CuAl-25, on the other hand, remained almost unaltered. The post irradiation tests at 250 deg. C showed a severe loss of ductility in the case of CuNiBe alloy. The irradiated CuAl-25 and CuCrZr specimens, on the other hand, exhibited a reasonable amount of uniform elongation. The results are briefly discussed in terms of thermal and irradiation stability of precipitates and particles and irradiation-induced segregation, precipitation and recovery of dislocation microstructure. (au) 7 tabs., 28 ills., 15 refs

  9. Transfer of test samples and wastes between post-irradiation test facilities (FMF, AGF, MMF)

    International Nuclear Information System (INIS)

    Ishida, Yasukazu; Suzuki, Kazuhisa; Ebihara, Hikoe; Matsushima, Yasuyoshi; Kashiwabara, Hidechiyo

    1975-02-01

    Wide review is given on the problems associated with the transfer of test samples and wastes between post-irradiation test facilities, FMF (Fuel Monitoring Facility), AGF (Alpha Gamma Facility), and MMF (Material Monitoring Facility) at the Oarai Engineering Center, PNC. The test facilities are connected with the JOYO plant, an experimental fast reactor being constructed at Oarai. As introductory remarks, some special features of transferring irradiated materials are described. In the second part, problems on the management of nuclear materials and radio isotopes are described item by item. In the third part, the specific materials that are envisaged to be transported between JOYO and the test facilities are listed together with their geometrical shapes, dimensions, etc. In the fourth part, various routes and methods of transportation are explained with many block charts and figures. Brief explanation with lists and drawings is also given to transportation casks and vessels. Finally, some future problems are discussed, such as the prevention of diffusive contamination, ease of decontamination, and the identification of test samples. (Aoki, K.)

  10. Defect sizing of post-irradiated nuclear fuels using grayscale thresholding in their radiographic images

    International Nuclear Information System (INIS)

    Chaudhary, Usman Khurshid; Iqbal, Masood; Ahmad, Munir

    2010-01-01

    Quantification of different types of material defects in a number of reference standard post-irradiated nuclear fuel image samples have been carried out by virtue of developing a computer program that takes radiographic images of the fuel as input. The program is based on user adjustable grayscale thresholding in the regime of image segmentation whereby it selects and counts the pixels having graylevel values less than or equal to the computed threshold. It can size the defects due to chipping in nuclear fuel, cracks, voids, melting, deformation, inclusion of foreign materials, heavy isotope accumulation, non-uniformity, etc. The classes of fuel range from those of research and power reactors to fast breeders and from pellets to annular and vibro-compacted fuel. The program has been validated against ground truth realities of some locally fabricated metallic plates having drilled holes of known sizes simulated as defects in them in which the results indicate that it either correctly selects and quantifies at least 94% of the actual required regions of interest in a given image or it gives less than 8.1% false alarm rate. Also, the developed program is independent of image size.

  11. Defect sizing of post-irradiated nuclear fuels using grayscale thresholding in their radiographic images

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhary, Usman Khurshid, E-mail: ukhurshid@hotmail.co [Department of Physics and Applied Mathematics, Pakistan Institute of Engineering and Applied Sciences, P.O. Nilore, Islamabad 45650 (Pakistan); Iqbal, Masood, E-mail: masiqbal@hotmail.co [Nuclear Engineering Division, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad 45650 (Pakistan); Ahmad, Munir [Nondestructive Testing Group, Directorate of Technology, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad 45650 (Pakistan)

    2010-10-15

    Quantification of different types of material defects in a number of reference standard post-irradiated nuclear fuel image samples have been carried out by virtue of developing a computer program that takes radiographic images of the fuel as input. The program is based on user adjustable grayscale thresholding in the regime of image segmentation whereby it selects and counts the pixels having graylevel values less than or equal to the computed threshold. It can size the defects due to chipping in nuclear fuel, cracks, voids, melting, deformation, inclusion of foreign materials, heavy isotope accumulation, non-uniformity, etc. The classes of fuel range from those of research and power reactors to fast breeders and from pellets to annular and vibro-compacted fuel. The program has been validated against ground truth realities of some locally fabricated metallic plates having drilled holes of known sizes simulated as defects in them in which the results indicate that it either correctly selects and quantifies at least 94% of the actual required regions of interest in a given image or it gives less than 8.1% false alarm rate. Also, the developed program is independent of image size.

  12. Advanced post-irradiation examination techniques for water reactor fuel. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    2002-03-01

    The purpose of the meeting was to provide and overview of the status of post-irradiation examination (PIE) techniques for water cooled reactor fuel assemblies and their components with emphasis given to advanced PIE techniques applied to high burnup fuel. Papers presented at the meeting described progress obtained in non-destructive (e.g. dimensional measurements, oxide layer thickness measurements, gamma scanning and tomography, neutron and X-ray radiography, etc.) and destructive PIE techniques (e.g. microstructural studies, elemental and isotopic analysis, measurement of physical and mechanical properties, etc.) used for investigation of water reactor fuel. Recent practice in high burnup fuel investigation revealed the importance of advanced PIE techniques, such as 3-D tomography, secondary ion mass spectrometry, laser flash, high resolution transmission and scanning electron microscopy, image analysis in microstructural studies, for understanding mechanisms of fuel behaviour under irradiation. Importance and needs for in-pile irradiation of samples and rodlets in instrumented rigs were also discussed. This TECDOC contains 20 individual papers presented at the meeting; each of the papers has been indexed separately

  13. Fuel Accident Condition Simulator (FACS) Furnace for Post-Irradiation Heating Tests of VHTR Fuel Compacts

    Energy Technology Data Exchange (ETDEWEB)

    Paul A Demkowicz; Paul Demkowicz; David V Laug

    2010-10-01

    Abstract –Fuel irradiation testing and post-irradiation examination are currently in progress as part of the Next Generation Nuclear Plant Fuels Development and Qualification Program. The PIE campaign will include extensive accident testing of irradiated very high temperature reactor fuel compacts to verify fission product retention characteristics at high temperatures. This work will be carried out at both the Idaho National Laboratory (INL) and the Oak Ridge National Laboratory, beginning with accident tests on irradiated fuel from the AGR-1 experiment in 2010. A new furnace system has been designed, built, and tested at INL to perform high temperature accident tests. The Fuel Accident Condition Simulator furnace system is designed to heat fuel specimens at temperatures up to 2000°C in helium while monitoring the release of volatile fission metals (e.g. Cs, Ag, Sr, Eu, and I) and fission gases (Kr, Xe). Fission gases released from the fuel to the sweep gas are monitored in real time using dual cryogenic traps fitted with high purity germanium detectors. Condensable fission products are collected on a plate attached to a water-cooled cold finger that can be exchanged periodically without interrupting the test. Analysis of fission products on the condensation plates involves dry gamma counting followed by chemical analysis of selected isotopes. This paper will describe design and operational details of the Fuel Accident Condition Simulator (FACS) furnace system, as well as preliminary system calibration results.

  14. Post-irradiation examination of fuel elements of Tarapur Atomic Power Station (Report-I)

    International Nuclear Information System (INIS)

    Bahl, J.K.; Sah, D.N.; Chatterjee, S.; Sivaramkrishnan, K.S.

    1979-01-01

    Detailed post-irradiation examination of three initial load fuel elements of the Tarapur Atomic Power Station (TAPS) has been carried out. The causes of the element failures have been analysed. It was observed that almost 90% of the length of the elements exoerienced nodular corrosion. It has been estimated that nodular corrosion would seriously affect the wall thickness and surface temperature of higher rated elements. Lunar shaped fret marks have also been observed at some spacer grid locations in the elements. The depth of the largest fret mark was measured to be 16.9% clad wall thickness. Detailed metallographic examination of the clad and fuel in the three elements has been done. The temperatures at different structural regions of the fuel cross-sections have been estimated. The change in fuel density during irradiation has been evaluated by comparing the irradiated fuel diameter with the mean pellet design diameter. The performance of the end plug welds and spacer grid sites in the elements has been assessed. The burnup distribution along the length of the elements has been evaluated by gamma scanning. The redistribution of fission products in the fuel has been examined by gamma scanning and beta-gamma autoradiography. Mechanical properties of the irradiated cladding have been examined by ring tensile testing. (auth.)

  15. Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target

    Energy Technology Data Exchange (ETDEWEB)

    Ammigan, K. [Fermilab; Hurh, P. [Fermilab; Sidorov, V. [Fermilab; Zwaska, R. [Fermilab; Asner, D. M. [PNL, Richland; Casella, Casella,A.M [PNL, Richland; Edwards, D. J. [PNL, Richland; Schemer-Kohrn, A. L. [PNL, Richland; Senor, D. J. [PNL, Richland

    2017-02-10

    The NT-02 neutrino target in the NuMI beamline at Fermilab is a 95 cm long target made up of segmented graphite fins. It is the longest running NuMI target, which operated with a 120 GeV proton beam with maximum power of 340 kW, and saw an integrated total proton on target of 6.1 1020. Over the last half of its life, gradual degradation of neutrino yield was observed until the target was replaced. The probable causes for the target performance degradation are attributed to radiation damage, possibly including cracking caused by reduction in thermal shock resistance, as well as potential localized oxidation in the heated region of the target. Understanding the long-termstructural response of target materials exposed to proton irradiation is critical as future proton accelerator sources are becoming increasingly more powerful. As a result, an autopsy of the target was carried out to facilitate post-irradiation examination of selected graphite fins. Advanced microstructural imaging and surface elemental analysis techniques were used to characterize the condition of the fins in an effort to identify degradation mechanisms, and the relevant findings are presented in this paper.

  16. Post-Irradiation Behaviour of I131 in TeO2

    International Nuclear Information System (INIS)

    Jaćimović, Lj.; Stevović, J.; Veljković, S.R.

    1965-01-01

    The system I 131 in TeO 2 is interesting because little is known about thermal chemical changes in this target. Radioiodine was produced by neutron irradiation of TeO 2 in the reactor. Irradiated TeO 2 was dissolved in diluted NaOH. The analysis of the iodine valency forms was made by ion exchange techniques. The thermal and radiation stability of TeO 2 was studied by using the spectrophotometric method for the determination of tellurium. Post-irradiation annealing of I 131 in TeO 2 was studied in dependence on the time and temperature of the heating. The main tendency of annealing was the reduction of radioiodine. The time dependence of this process indicates a fast change at high temperatures. The curves are more complex at lower temperatures. The annealing may appear complex because of the variety of thermal reactions of iodine intermediary. It may react with products of the following processes: tellurium recoil and corresponding hot zone, beta transition of Te 131 and TeO 2 itself. The kinetics of these changes was considered and an estimation of the processes during annealing was made. The influence of the neutron flux on the kinetics of annealing was also studied. (author) [fr

  17. Modeling plastic deformation of post-irradiated copper micro-pillars

    Energy Technology Data Exchange (ETDEWEB)

    Crosby, Tamer, E-mail: tcrosby@ucla.edu; Po, Giacomo, E-mail: gpo@ucla.edu; Ghoniem, Nasr M., E-mail: ghoniem@ucla.edu

    2014-12-15

    We present here an application of a fundamentally new theoretical framework for description of the simultaneous evolution of radiation damage and plasticity that can describe both in situ and ex situ deformation of structural materials [1]. The theory is based on the variational principle of maximum entropy production rate; with constraints on dislocation climb motion that are imposed by point defect fluxes as a result of irradiation. The developed theory is implemented in a new computational code that facilitates the simulation of irradiated and unirradiated materials alike in a consistent fashion [2]. Discrete Dislocation Dynamics (DDD) computer simulations are presented here for irradiated fcc metals that address the phenomenon of dislocation channel formation in post-irradiated copper. The focus of the simulations is on the role of micro-pillar boundaries and the statistics of dislocation pinning by stacking-fault tetrahedra (SFTs) on the onset of dislocation channel and incipient surface crack formation. The simulations show that the spatial heterogeneity in the distribution of SFTs naturally leads to localized plastic deformation and incipient surface fracture of micro-pillars.

  18. Technical review on irradiation tests and post-irradiation examinations in JMTR

    International Nuclear Information System (INIS)

    2017-07-01

    The Japan Materials Testing Reactor (JMTR) has been contributing to various R and D activities in the nuclear research such as the fundamental research of nuclear materials/ fuels, safety research and development of power reactors, radio isotope (RI) production since its beginning of the operation in 1968. Irradiation technologies and post irradiation examination (PIE) technologies are the important factors for irradiation test research. Moreover, these technologies induce the breakthrough in area of nuclear research. JMTR has been providing unique capabilities for the irradiation test research for about 40 years since 1968. In future, any needs for irradiation test research used irradiation test reactors will continue, such as R and D of generation 4 power reactors, fundamental research of materials/fuels, RI production. Now, decontamination and new research reactor construction are common issue in the world according to aging. This situation is the same in Japan. This report outlines irradiation and PIE technologies developed at JMTR in 40 years to contribute to the technology transfer and human resource development. We hope that this report will be used for the new research rector design as well as the irradiation test research and also used for the human resource development of nuclear engineers in future. (author)

  19. Post-irradiation regeneration of early B-lymphocyte precursor cells in mouse bone marrow

    International Nuclear Information System (INIS)

    Park, Y.-H.; Osmond, D.G.

    1989-01-01

    To examine the sequential development of early B-cell precursors in mouse bone marrow, B-lineage cells have been examined during a wave of post-irradiation regeneration. Cell phenotypes have been defined for (i) terminal deoxynucleotidyl transferase (TdT); (ii) B220 glycoprotein, (iii) μ heavy chains in the cytoplasm (cμ) and at the cell surface (sμ). Three populations of μ - cells (TdT + 14.8 - ; TdT + 14.8 + ; TdT - 14.8 + ) have been proposed to be early B-cell precursors which would give rise to cμ + sμ - pre-B cells and to sμ + B lymphocytes. The timing, cell-size shifts and progressive amplification of the waves of regeneration accord with a dynamic model in which the TdT + 14.8 - , TdT + 14.8 + and TdT - 14.8 + cells form three successive stages in B-cell differentiation before the expression of μ chains, presumptively including the stage of μ chain gene rearrangement. In addition, the results provide an experimental system for the enrichment of early B-cell precursors in mouse bone marrow. (author)

  20. Microstructural evolution of nanochannel CrN films under ion irradiation at elevated temperature and post-irradiation annealing

    Science.gov (United States)

    Tang, Jun; Hong, Mengqing; Wang, Yongqiang; Qin, Wenjing; Ren, Feng; Dong, Lan; Wang, Hui; Hu, Lulu; Cai, Guangxu; Jiang, Changzhong

    2018-03-01

    High-performance radiation tolerance materials are crucial for the success of future advanced nuclear reactors. In this paper, we present a further investigation that the "vein-like" nanochannel films can enhance radiation tolerance under ion irradiation at high temperature and post-irradiation annealing. The chromium nitride (CrN) nanochannel films with different nanochannel densities and the compact CrN film are chosen as a model system for these studies. Microstructural evolution of these films were investigated using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Elastic Recoil Detection (ERD) and Grazing Incidence X-ray Diffraction (GIXRD). Under the high fluence He+ ion irradiation at 500 °C, small He bubbles with low bubble densities are observed in the irradiated nanochannel CrN films, while the aligned large He bubbles, blistering and texture reconstruction are found in the irradiated compact CrN film. For the heavy Ar2+ ion irradiation at 500 °C, the microstructure of the nanochannel CrN RT film is more stable than that of the compact CrN film due to the effective releasing of defects via the nanochannel structure. Under the He+ ion irradiation and subsequent annealing, compared with the compact film, the nanochannel films have excellent performance for the suppression of He bubble growth and possess the strong microstructural stability. Basing on the analysis on the sizes and number densities of bubbles as well as the concentrations of He retained in the nanochannel CrN films and the compact CrN film under different experimental conditions, potential mechanism for the enhanced radiation tolerance are discussed. Nanochannels play a crucial role on the release of He/defects under ion irradiation. We conclude that the tailored "vein-like" nanochannel structure may be used as advanced radiation tolerance materials for future nuclear reactors.

  1. Defects annihilation behavior of neutron-irradiated SiC ceramics densified by liquid-phase-assisted method after post-irradiation annealing

    Directory of Open Access Journals (Sweden)

    Mohd Idzat Idris

    2016-12-01

    Full Text Available Numerous studies on the recovery behavior of neutron-irradiated high-purity SiC have shown that most of the defects present in it are annihilated by post-irradiation annealing, if the neutron fluence is less than 1×1026 n/m2 (>0.1MeV and the irradiation is performed at temperatures lower than 973K. However, the recovery behavior of SiC fabricated by the nanoinfiltrated and transient eutectic phase (NITE process is not well understood. In this study, the effects of secondary phases on the irradiation-related swelling and recovery behavior of monolithic NITE-SiC after post-irradiation annealing were studied. The NITE-SiC specimens were irradiated in the BR2 reactor at fluences of up to 2.0–2.5×1024 n/m2 (E>0.1MeV at 333–363K. This resulted in the specimens swelling up ∼1.3%, which is 0.1% higher than the increase seen in concurrently irradiated high-purity SiC. The recovery behaviors of the specimens after post-irradiation thermal annealing were examined using a precision dilatometer; the specimens were heated at temperatures of up to 1673K using a step-heating method. The recovery curves were analyzed using a first-order model, and the rate constants for each annealing step were obtained to determine the activation energy for volume recovery. The NITE-A specimen (containing 12 wt% sintering additives recovered completely after annealing at ∼1573K; however, it shrank because of the volatilization of the oxide phases at 1673K. The NITE-B specimen (containing 18wt% sintering additives did not recover fully, since the secondary phase (YAG was crystallized during the annealing process. The recovery mechanism of NITE-A SiC was based on the recombination of the C and Si Frenkel pairs, which were very closely sited or only slightly separated at temperatures lower than 1223K, as well as the recombination of the slightly separated C Frenkel pairs and the migration of C and Si interstitials at temperatures of 1223–1573K. That is to say, the

  2. Protective effects of acemannan against radiation induced damage in Swiss albino mice

    International Nuclear Information System (INIS)

    Kumar, Sumit; Tiku, Ashu Bhan

    2013-01-01

    Aloe vera is one of the well known medicinal plant and posses a large no. of beneficial bioactive components like Anthraquinone, C-glycosides, anthrones, emodin, acemannan etc. Acemannan (poly-acetylated mannose) is one of the active component present in aloe vera gel and has anticancerous and antimicrobial properties. It has also been reported to have wound healing properties and has role as immunomodulator. The objective of the present study was to evaluate protective efficacy of acemannan against radiation induced damage in in-vitro and in in-vivo using murine splenocytes and Swiss albino mice as a model system. In vitro studies were done using primary mouse splenocytes cultures and effect of radiation on cell proliferation, viability, ROS, DNA damage and apoptosis were studies using MTT, trypan blue, DCFDA, single cell gel electrophoresis and ladder assay respectively. For in-vivo studies mice were pretreated with different doses of drug for 7 days followed by irradiation (5 Gy). Twenty four hours post-irradiation mice was sacrificed to observe the activity of antioxidant enzymes and level of protein expression. Acemannan showed a significant induction of proliferation of splenocytes in radiation treated groups both in in-vitro and in in-vivo. Beside a decrease in radiation induced ROS and DNA damage was observed in in-vitro system. Acemannan treatment was able to reduce the radiation induced apoptosis by about 50% both in in-vitro and in in-vivo. In in-vivo acemannan helps in the restoration of the antioxidant enzyme level (catalase, SOD, DTD and GST) besides maintaining the proper redox status via GSH, in irradiated mice. In our studies a dose of 50 mg/kg body wt of acemannan showed the best protective effects. On the basis of the above results it could be concluded that acemannan may have radioprotective potential. (author)

  3. Post-irradiation examination of a 13000C-HTR fuel experiment Project J 96.M3

    International Nuclear Information System (INIS)

    Bueger, J. de; Roettger, H.

    1977-01-01

    A large variety of loose coated fuel particles have been irradiated in the BR2 at Mol/Belgium at temperatures between 1200 0 C and 1400 0 C and up to a fast neutron fluence of 1.2x1022 cm -2 (E>0.1 MeV) as a Euratom sponsored experiment for the advanced testing of HTR fuel. The specimens have been provided by Belgonucleaire and the Dragon Project. A short description of the experiment as well as the results of post-irradiation examination mainly carried out at Petten (N.H.), The Netherlands, are presented here. The post-irradiation examination has shown that the required performance can be achieved by a number of the tested fuel specimens without serious damage

  4. Post-irradiation analysis of low enriched U-Mo/Al dispersions fuel miniplate tests, RERTR 4 and 5

    International Nuclear Information System (INIS)

    Hofman, G.L.; Finlay, M.R.; Kim, Y.S.

    2005-01-01

    Interpretation of the post irradiation data of U-Mo/Al dispersion fuel mini plates irradiated in the Advanced Test Reactor to a maximum U-235 burn up of 80% are presented. The analyses addresses fuel swelling and porosity formation as these fuel performance issues relate to fuel fabrication and irradiation parameters. Specifically, mechanisms involved in the formation of porosity observed in the U-Mo/Al interaction phase are discussed and, means of mitigating or eliminating this irradiation phenomenon are offered. (author)

  5. International interest in the BONAPARTE measurement bench. Post-irradiation examination of lower-enriched fuel plates

    International Nuclear Information System (INIS)

    2014-01-01

    The Belgian Nuclear Research Center SCK-CEN has developed a measurement bench (BONAPARTE) for the non-destructive analysis on fuel plate and rod type fuel elements. BONAPARTE is a modular device that can be employed for many purposes. The article discusses the employment of the BONAPARTE device for the accurate full post-irradiation mapping of fuel plate swelling with degree of precision of just a few micrometers.

  6. Post-irradiation examination of HTR-fuel at the Austrian Research Centre Seibersdorf Ltd

    International Nuclear Information System (INIS)

    Reitsamer, G.; Proksch, E.; Stolba, G.; Strigl, A.; Falta, G.; Zeger, J.

    1985-01-01

    Austrian R and D activities in the HTR-field reach back almost to the beginning of this advanced reactor line. For more than 20 years post-irradiation examination (PIE) of HTR-fuel has been performed at the laboratories of the Austrian Research Centre Seibersdorf Ltd. (OEFZS) (formerly OESGAE) and a high degree of qualification has been achieved in the course of that time. Most of the PIE-work has been carried out by international cooperation on contract basis with the OECD-DRAGON-project and with KFA-Juelich (FRG). There has also been some collaboration with GA (USA), Belgonucleaire and others in the past. HTR-fuel elements contain the fissile and fertile materials in form of coated particles (CPs) which are embedded in a graphite matrix. Because of this special design it has been necessary from the very beginning of the PIE work up to now to develop new methods (i.e. fuel element disintegration methods, chlorine gas leach, single particle examination techniques...) as well as to adapt and improve already existing methods (i.e. gamma spectrometry, mass-spectrometry, optical methods...). The main interests on PIE-work at Seibersdorf are concentrated on particle performance, fission product distribution and the 'free' Uranium content (contamination and broken particles) of the fuel elements (fuel spheres or cylindrical compacts). A short compilation of the applied methods and of available instrumental facilities is given as follows: deconsolidation of fuel elements; equipment for electrochemical deconsolidation; examinations and measurements of graphite and electrolyte samples; examination of coated particles; single particle examinations

  7. Post-irradiation examination of CANDU fuel bundles fuelled with (Th, Pu)O2

    International Nuclear Information System (INIS)

    Karam, M.; Dimayuga, F.C.; Montin, J.

    2010-01-01

    AECL has extensive experience with thoria-based fuel irradiations as part of an ongoing R&D program on thorium within the Advanced Fuel Cycles Program. The BDL-422 experiment was one component of the thorium program that involved the fabrication and irradiation testing of six Bruce-type bundles fuelled with (Th, Pu)O 2 pellets. The fuel was manufactured in the Recycle Fuel Fabrication Laboratories (RFFL) at Chalk River allowing AECL to gain valuable experience in fabrication and handling of thoria fuel. The fuel pellets contained 86.05 wt.% Th and 1.53 wt.% Pu in (Th, Pu)O 2 . The objectives of the BDL-422 experiment were to demonstrate the ability of 37-element geometry (Th, Pu)O 2 fuel bundles to operate to high burnups up to 1000 MWh/kgHE (42 MWd/kgHE), and to examine the (Th, Pu)O 2 fuel performance. This paper describes the post-irradiation examination (PIE) results of BDL-422 fuel bundles irradiated to burnups up to 856 MWh/kgHE (36 MWd/kgHE), with power ratings ranging from 52 to 67 kW/m. PIE results for the high burnup bundles (>1000 MWh/kgHE) are being analyzed and will be reported at a later date. The (Th, Pu)O 2 fuel performance characteristics were superior to UO 2 fuel irradiated under similar conditions. Minimal grain growth was observed and was accompanied by benign fission gas release and sheath strain. Other fuel performance parameters, such as sheath oxidation and hydrogen distribution, are also discussed. (author)

  8. Integration of post-irradiation examination results of failed WWER fuel rods

    International Nuclear Information System (INIS)

    Smirnov, A.; Markov, D.; Smirnov, V.; Polenok, V.; Perepelkin, S.

    2003-01-01

    The aim of the work is to investigate the causes of WWER fuel rod failures and to reveal the dependence of the failed fuel rod behaviour and state on the damage characteristics and duration of their operation in the core. The post-irradiation examination of 12 leaky fuel assemblies (5 for WWER-440 and 7 for WWER-1000) has been done at SSC RF RIAR. The results show that the main mechanism responsible for the majority of cases of the WWER fuel rod perforation is debris-damage of the claddings. Debris fretting of the claddings spread randomly over the fuel assembly cross-section and they are registered in the area of the bundle supporting grid or under the lower spacer grids along the fuel assembly height. In the WWER fuel rods, the areas of secondary hydrogenating of cladding are spaced from the primary defects by ∼2500-3000 mm, as a rule, and are often adjacent closely to the upper welded joints. There is no pronounced dependence of the distance between the primary and secondary cladding defects neither on the linear power, at which the fuel rods were operated, nor on the period of their operation in the leaky state. The time period of the significant secondary damage formation is about 250 ± 50 calendar days for the WWER fuel rods with slight through primary defects (∼0.1 - 0.5 mm 2 ) operated in the linear power range 170-215 W/cm. Cladding degradation, taking place due to the secondary hydrogenating, does not occur in case of large through debris-defects during operation up to 600 calendar days

  9. Post-irradiation examination of a failed PHWR fuel bundle of KAPS-2

    International Nuclear Information System (INIS)

    Mishra, Prerna; Unnikrishnan, K.; Viswanathan, U.K.; Shriwastaw, R.S.; Singh, J.L.; Ouseph, P.M.; Alur, V.D.; Singh, H.N.; Anantharaman, S.; Sah, D.N.

    2006-08-01

    Detailed post irradiation examination was carried out on a PHWR fuel bundle irradiated at Kakrapar Atomic Power Station unit 2 (KAPS-2). The fuel bundle had failed early in life at a low burnup of 387 MWd/T. Non destructive and destructive examination was carried out to identify the cause of fuel failure. Visual examination and leak testing indicated failure in two fuel pins of the outer ring of the bundle in the form of axial cracks near the end plug location. Ultrasonic testing of the end cap weld indicated presence of lack of fusion type defect in the two fuel pins. No defect was found in other fuel pins of the bundle. Metallographic examination of fuel sections taken from the crack location in the failed fuel pin showed extensive restructuring of fuel. The centre temperature of the fuel had exceeded 1700 degC at this location in the failed fuel pin, whereas fuel centre temperature in the un-failed fuel pin was only about 1300 degC. Severe fuel clad interaction was observed in the failed fuel pin at and near the location of failure but no such interaction was observed in the un-failed fuel pins. Several incipient cracks originating from the inside surface were found in the cladding near failure location in addition to the main through wall crack. The incipient cracks were filled with interaction products and hydride platelets were present at tip of the cracks. It was concluded from the observations that the primary cause of failure was the presence of a part-wall defect in the end cap weld of the fuel pins. These defects opened up during reactor operation leading to steam ingress into the fuel, which caused high fuel centre temperature and severe fuel-cladding interaction resulting in secondary failures. A more stringent inspection and quality control of end plug weld during fabrication using ultrasonic test has been recommended to avoid such failure. (author)

  10. Post-irradiation examination of HTR-fuel at the Austrian Research Centre Seibersdorf Ltd

    Energy Technology Data Exchange (ETDEWEB)

    Reitsamer, G; Proksch, E; Stolba, G; Strigl, A; Falta, G; Zeger, J [Department of Chemistry, Austrian Research Centre Seibersdorf Ltd., Seibersdorf (Austria)

    1985-07-01

    Austrian R and D activities in the HTR-field reach back almost to the beginning of this advanced reactor line. For more than 20 years post-irradiation examination (PIE) of HTR-fuel has been performed at the laboratories of the Austrian Research Centre Seibersdorf Ltd. (OEFZS) (formerly OESGAE) and a high degree of qualification has been achieved in the course of that time. Most of the PIE-work has been carried out by international cooperation on contract basis with the OECD-DRAGON-project and with KFA-Juelich (FRG). There has also been some collaboration with GA (USA), Belgonucleaire and others in the past. HTR-fuel elements contain the fissile and fertile materials in form of coated particles (CPs) which are embedded in a graphite matrix. Because of this special design it has been necessary from the very beginning of the PIE work up to now to develop new methods (i.e., fuel element disintegration methods, chlorine gas leach, single particle examination techniques...) as well as to adapt and improve already existing methods (i.e. gamma spectrometry, mass-spectrometry, optical methods...). The main interests on PIE-work at Seibersdorf are concentrated on particle performance, fission product distribution and the 'free' Uranium content (contamination and broken particles) of the fuel elements (fuel spheres or cylindrical compacts). A short compilation of the applied methods and of available instrumental facilities is given as follows: deconsolidation of fuel elements; equipment for electrochemical deconsolidation; examinations and measurements of graphite and electrolyte samples; examination of coated particles; single particle examinations.

  11. Enhancement of tumor cell killing in vitro by pre- and post-irradiation exposure to aclacinomycin A

    International Nuclear Information System (INIS)

    Bill, C.A.; Mendoza, A.; Vrdoljak, E.; Tofilon, P.J.

    1993-01-01

    Aclacinomycin A (ACM), a potent inducer of leukemic cell differentiation, significantly enhances the radiosensitivity of a human colon tumor cell line (Clone A) when cultures are exposed to 15-nM concentrations for 3 days before irradiation. We now demonstrate that incubation with ACM after irradiation can also enhance Clone A cell killing. The maximum increase in cell killing, based on colony-forming ability, occurred when Clone A cells were exposed for 1 h to 5 μM ACM model added 1 or 2 h after irradiation. The post-irradiation ACM protocol reduced the terminal slope (as reflected by D o ) of the radiation cell survival curve with no change in the low-dose, shoulder region of the curve (D q value). In contrast, for pre-irradiation treatment with ACM (15 nM, 3 days), the shoulder region of the curve was reduced with no change in the terminal slope. For pre- and post-irradiation ACM treatment the dose enhancement factors at 0.10 survival were 1.22 and 1.28, respectively. When ACM was given both before and after irradiation both the shoulder and terminal slope values decreased to produce a dose enhancement factor at a surviving fraction of 0.10 of 1.50. These data suggest that the enhanced cell killing produced by pre- and post-irradiation treatment with ACM is achieved through different mechanisms. (author) 26 refs., 3 tabs., 2 figs

  12. Microstructure and mechanical properties of neutron irradiated OFHC-copper before and after post-irradiation annealing

    International Nuclear Information System (INIS)

    Singh, B.N.; Edwards, D.J.; Toft, P.

    2001-02-01

    Tensile specimens of OFHC-copper were irradiated with fission neutrons in the DR-3 reactor at Risoe National Laboratory at 100 deg. C to different displacement dose levels in the range of 0.01 to 0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 deg. C whereas other were given a post-irradiation annealing at 300 deg. C for 50 h and subsequently tested at 100 deg. C. Transmission electron microscopy was used to characterize the microstructure of specimens in the as-irradiation as well as irradiation and annealed conditions both before and after tensile deformation. The results show that while the interstitial loop microstructure coarsens with irradiation dose, no significant changes are observed in the population of stacking fault tetrahedra. The results also illustrates that the post-irradiation annealing leads to only a partial recovery and that the level of recovery depends on the irradiation dose level. However, the post-irradiation annealing eliminates the problem of yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade induced source hardening (CISH) and the dispersed barrier hardening (DBH) models. Both technological and scientific implications of these results are considered. (au)

  13. Protective effect of an herbal preparation (HemoHIM) on radiation-induced intestinal injury in mice.

    Science.gov (United States)

    Kim, Sung Ho; Lee, Hae June; Kim, Joong Sun; Moon, Changjong; Kim, Jong Choon; Park, Hae-Ran; Jung, Uhee; Jang, Jong Sik; Jo, Sung Kee

    2009-12-01

    The protective properties of an herbal preparation (HemoHIM) against intestinal damage were examined by evaluating its effects on jejunal crypt survival, morphological changes, and apoptosis in gamma-irradiated mice. The mice were whole-body irradiated with 12 Gy for the examination of jejunal crypt survival and any morphological changes and with 2 Gy for the detection of apoptosis and Ki-67 labeling. Irradiation was conducted using (60)Co gamma-rays. HemoHIM treatment was administered intraperitonially at a dosage of 50 mg/kg of body weight at 36 and 12 hours pre-irradiation and 30 minutes post-irradiation or orally at a dosage of 250 mg/kg of body weight/day for 7 or 11 days before necropsy. The HemoHIM-treated group displayed a significant increase in survival of jejunal crypts, when compared to the irradiation controls. HemoHIM treatment decreased intestinal morphological changes such as crypt depth, villus height, mucosal length, and basal lamina length of 10 enterocytes after irradiation. Furthermore, the administration of HemoHIM protected intestinal cells from irradiation-induced apoptosis. These results suggested that HemoHIM may be therapeutically useful to reduce intestinal injury following irradiation.

  14. Molecular mechanism of cell damage and protection against ionizing radiation. Communication 3. Correlation between the protective effect and development of a non-specific reaction

    International Nuclear Information System (INIS)

    Veksler, A.M.; Ermekova, V.M.; Kozlovich, L.I.

    1975-01-01

    The dynamics of reversible unspecific reaction (UR) of chinese hamster fibroblast cell culture to hypothermia and cysteamine addition has been studied. A correlation between UR development and radioresistance has been established. The post-irradiation protection has been shown to grow undulatorilly o cysteamine addition at different times after irradiation. This is explained by superimposition of two processes: realization of latent lesions which is delayed by UR development, and repair of these lesions by the enzymatic system the activity of which changes periodicallY, also as a result of UR development

  15. AGR-1 Fuel Compact 6-3-2 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Paul demkowicz; jason Harp; Scott Ploger

    2012-12-01

    Destructive post-irradiation examination was performed on fuel Compact 6-3-2, which was irradiated in the AGR-1 experiment to a final compact average burnup of 11.3% FIMA and a time-average, volume-average temperature of 1070°C. The analysis of this compact was focused on characterizing the extent of fission product release from the particles and examining particles to determine the condition of the kernels and coating layers. The work included deconsolidation of the compact and leach-burn-leach analysis, visual inspection and gamma counting of individual particles, measurement of fuel burnup by several methods, metallurgical preparation of selected particles, and examination of particle cross-sections with optical microscopy. A single particle with a defective SiC layer was identified during deconsolidation-leach-burn-leach analysis, which is in agreement with previous measurements showing elevated cesium in the Capsule 6 graphite fuel holder associated with this fuel compact. The fraction of the compact europium inventory released from the particles and retained in the matrix was relatively high (approximately 6E-3), indicating release from intact particle coatings. The Ag-110m inventory in individual particles exhibited a very broad distribution, with some particles retaining =80% of the predicted inventory and others retaining less than 25%. The average degree of Ag-110m retention in 60 gamma counted particles was approximately 50%. This elevated silver release is in agreement with analysis of silver on the Capsule 6 components, which indicated an average release of 38% of the Capsule 6 inventory from the fuel compacts. In spite of the relatively high degree of silver release from the particles, virtually none of the Ag-110m released was found in the compact matrix, and presumably migrated out of the compact and was deposited on the irradiation capsule components. Release of all other fission products from the particles appears to be less than a single

  16. Effective dose: a radiation protection quantity

    CERN Document Server

    Menzel, H G

    2012-01-01

    Modern radiation protection is based on the principles of justification, limitation, and optimisation. Assessment of radiation risks for individuals or groups of individuals is, however, not a primary objective of radiological protection. The implementation of the principles of limitation and optimisation requires an appropriate quantification of radiation exposure. The International Commission on Radiological Protection (ICRP) has introduced effective dose as the principal radiological protection quantity to be used for setting and controlling dose limits for stochastic effects in the regulatory context, and for the practical implementation of the optimisation principle. Effective dose is the tissue weighted sum of radiation weighted organ and tissue doses of a reference person from exposure to external irradiations and internal emitters. The specific normalised values of tissue weighting factors are defined by ICRP for individual tissues, and used as an approximate age- and sex-averaged representation of th...

  17. protective effect of combined administration of isoflavones genistein and daidzein against irradiation -induced damage in female rats

    International Nuclear Information System (INIS)

    Ashry, O.M.

    2009-01-01

    The renewed interests in the search for plant-derived drugs in the field of alternative medicine necessitate further studies. the present work aimed to evaluate the efficacy of diet phyto estrogens such as diadzein and genistein on repairing oxidative damage and protecting calcium homeostatic system against radiation induced disorders in female rats. soybean isoflavones were orally administered in a dose of 9 mg/kg body wt/day for 21 and 26 days. irradiated animals received diadzein and genistein for 11 consecutive days before exposing female rats to 6 Gy gamma irradiation and continued to receive soybean isoflavones until sacrificed 10 and 15 days post irradiation . Irradiation induced significant decrease in white blood cells(WBCs), red blood cells (RBCs), haemoglobin (HB), haematocrit (Ht %), glutathione (GSH), calcium (CA) and estradiol, while it induced significant elevation in serum malondialdehyde(MDA), inorganic phosphorus, thyroxine 3 (T 3 ) and thyroxine 4 (T 4 ), 10 and 15 days post -irradiation . diadzein and genistein treatment before and through irradiation accelerated the recovery of circulating WBCs and RBCs, elevated HB, Hct % GSH meanwhile hindered the depression in CA. Soy isoflavones depressed MDA and ameliorated the increase in T 3 , T 4 and elevated estradiol and phosphorus levels 10 and 15 days post irradiation. the results recommend combined treatment with genistein and daidzein to mitigate irradiation-induced damage and bon loss and suggest clinical application of these isoflavones in radiotherapy

  18. Mechanism of protection of bystander cells by exogenous carbon monoxide: Impaired response to damage signal of radiation-induced bystander effect

    International Nuclear Information System (INIS)

    Han, W.; Yu, K.N.; Wu, L.J.; Wu, Y.C.; Wang, H.Z.

    2011-01-01

    A protective effect of exogenous carbon monoxide (CO), generated by CO releasing molecule ticarbonyldichlororuthenium (II) dimer (CORM-2), on the bystander cells from the toxicity of radiation-induced bystander effect (RIBE) was revealed in our previous study. In the present work, a possible mechanism of this CO effect was investigated. The results from medium transfer experiments showed that α-particle irradiated Chinese hamster ovary (CHO) cells would release nitric oxide (NO), which was detected with specific NO fluorescence probe, to induce p53 binding protein 1 (BP1) formation in the cell population receiving the medium, and the release peak was found to be at 1 h post irradiation. Treating the irradiated or bystander cells separately with CO (CORM-2) demonstrated that CO was effective in the bystander cells but not the irradiated cells. Measurements of NO production and release with a specific NO fluorescence probe also showed that CO treatment did not affect the production and release of NO by irradiated cells. Protection of CO on cells to peroxynitrite, an oxidizing free radical from NO, suggested that CO might protect bystander cells via impaired response of bystander cells to NO, a RIBE signal in our research system.

  19. Mechanism of protection of bystander cells by exogenous carbon monoxide: Impaired response to damage signal of radiation-induced bystander effect

    Energy Technology Data Exchange (ETDEWEB)

    Han, W. [Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Kowloon (Hong Kong); Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China); Yu, K.N., E-mail: peter.yu@cityu.edu.hk [Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Kowloon (Hong Kong); Wu, L.J. [Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China); Wu, Y.C. [Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China); School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230029 (China); Wang, H.Z. [Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031 (China)

    2011-05-10

    A protective effect of exogenous carbon monoxide (CO), generated by CO releasing molecule ticarbonyldichlororuthenium (II) dimer (CORM-2), on the bystander cells from the toxicity of radiation-induced bystander effect (RIBE) was revealed in our previous study. In the present work, a possible mechanism of this CO effect was investigated. The results from medium transfer experiments showed that {alpha}-particle irradiated Chinese hamster ovary (CHO) cells would release nitric oxide (NO), which was detected with specific NO fluorescence probe, to induce p53 binding protein 1 (BP1) formation in the cell population receiving the medium, and the release peak was found to be at 1 h post irradiation. Treating the irradiated or bystander cells separately with CO (CORM-2) demonstrated that CO was effective in the bystander cells but not the irradiated cells. Measurements of NO production and release with a specific NO fluorescence probe also showed that CO treatment did not affect the production and release of NO by irradiated cells. Protection of CO on cells to peroxynitrite, an oxidizing free radical from NO, suggested that CO might protect bystander cells via impaired response of bystander cells to NO, a RIBE signal in our research system.

  20. Effect of radiation on the nutritive value of post irradiated potatoes

    International Nuclear Information System (INIS)

    Pringsulaka, Vachira.

    1983-12-01

    Harvested fresh potatoes of Spunta variety, were irradiated at 0, 60, 90, 120 and 150 gray and then stored at three temperatures; room temperature (30+-5 deg C) with 55-65 percent R.H., and 15 deg C and 10 deg C both with 85-95 percent R.H. The biochemical assay of total sugar, protein, and vitamin C were conducted for the determination of changing in nutritive value. The results of the experiment are as follows. Both non-irradiated and irradiated potatoes, stored at room temperature with 55-65 percent R.H., showed higher changing in percentage of total sugar and vitamin C, but only slightly changing in protein was observed. Furthermore, no significant difference was found in nutritive value between irradiated and non-irradiated potatoes stored at 15 deg C and 10 deg C with 85-95 percent R.H

  1. 8 x 8 fuel surveillance program at Monticello site - end of Cycle 6: fourth post-irradiation inspection, October 1978

    International Nuclear Information System (INIS)

    Skarshaug, N.H.

    1980-09-01

    A fuel surveillance program for a lead 8 x 8 reload fuel assembly was implemented at the Monticello Nuclear Power Station in May 1974 prior to Reactor Cycle 3. Inspection results of the fourth post-irradiation inspection performed on this surveillance fuel assembly in October 1978 at EOC 6, after a bundle average exposure of 25,900 MWd/MT, are presented. The measurement techniques, results obtained and comparisons to previous measurements are discussed. The bundle and individual rods examined exhibited characteristics of normal operation and were approved for continued irradiation during Monticello operating Cycle 7

  2. AGR-1 Compact 4-1-1 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ploger, Scott A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); van Rooyen, Isabella J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-02-01

    Destructive post-irradiation examination was performed on AGR-1 fuel Compact 4-1-1, which was irradiated to a final compact-average burnup of 19.4% FIMA (fissions per initial metal atom) and a time-average, volume-average temperature of 1072°C. The analysis of this compact focused on characterizing the extent of fission product release from the particles and examining particles to determine the condition of the kernels and coating layers. The work included deconsolidation of the compact and leach-burn-leach analysis, visual inspection and gamma counting of individual particles, metallurgical preparation of selected particles, and examination of particle cross-sections with optical microscopy, electron microscopy, and elemental analysis. Deconsolidation-leach-burn-leach (DLBL) analysis revealed no particles with failed TRISO or failed SiC layers (as indicated by very low uranium inventory in all of the leach solutions). The total fractions of the predicted compact inventories of fission products Ce-144, Cs-134, Cs-137, and Sr-90 that were present in the compact outside of the SiC layers were <2×10-6, based on DLBL data. The Ag-110m fraction in the compact outside the SiC layers was 3.3×10-2, indicating appreciable release of silver through the intact coatings and subsequent retention in the OPyC layers or matrix. The Eu-154 fraction was 2.4×10-4, which is equivalent to the inventory in one average particle, and indicates a small but measurable level of release from the intact coatings. Gamma counting of 61 individual particles indicated no particles with anomalously low fission product retention. The average ratio of measured inventory to calculated inventory was close to a value of 1.0 for several fission product isotopes (Ce-144, Cs-134, and Cs-137), indicating good retention and reasonably good agreement with the predicted inventories. Measured-to-calculated (M/C) activity ratios for fission products Eu-154, Eu-155, Ru-106, Sb

  3. Post-irradiation examination of Al-61 wt% U3Si fuel rods from the NRU reactor

    International Nuclear Information System (INIS)

    Sears, D.F.; Wang, N.

    1997-01-01

    This paper describes the post-irradiation examination of 4 intact low enrichment uranium (LEU) fuel rods from the national research universal (NRU) reactor at the Chalk River Laboratories of AECL. The rods were irradiated during the period 1993 through 1995, under typical driver fuel operating conditions in NRU, i.e., nominal D 2 O coolant inlet temperature 37E C, inlet pressure 654 kPa and mass flow 12.4 L/s. Irradiation exposures ranged from 147 to 251 full-power days, corresponding to 40 to 84 atom % 235 U burnup. The maximum rod power was ∼2 MW, with element linear power ratings up to 68 kW/m. Post-irradiation examinations, conducted in 1997, focused on optical metallography to measure cladding oxide thickness and fuel core and cladding microstructural examinations. The cladding oxide was approximately 24 : m thick at the mid-plane of fuel rods irradiated to 251 full-power days, with small areas up to 34 : m thick on the fins. The cladding retained significant ductility after irradiation, and its microstructure appeared unchanged. Fuel core diametral increases were small (up to 4%) and within the range previously observed on Al-61 wt% U 3 Si fuel irradiated in the NRU reactor. (author)

  4. Post-irradiation examination of A1-61 wt % U3Si fuel rods from the NRU reactor

    International Nuclear Information System (INIS)

    Sears, D.F.; Wang, N.

    1997-09-01

    This paper describes the post-irradiation examination of 4 intact low-enrichment uranium (LEU) fuel rods from the national research universal (NRU) reactor at the Chalk River Laboratories of AECL. The rods were irradiated during the period 1993 through 1995, under typical driver fuel operating conditions in NRU, i.e., nominal D 2 0 coolant inlet temperature 37 degrees C, inlet pressure 654 kPa and mass flow 12.4 L/s. Irradiation exposures ranged from 147 to 251 full-power days, corresponding to 40 to 84 atom % 235 U burnup. The maximum rod power was ∼2 MW, with element linear power ratings up to 68 kW/m. Post-irradiation examinations, conducted in 1997, focused on optical metallography to measure cladding oxide thickness and fuel core and cladding microstructural examinations. The cladding oxide was approximately 24 μm thick at the mid-plane of fuel rods irradiated to 251 full-power days, with small areas up to 34 μm thick on the fins. The cladding retained significant ductility after irradiation, and its microstructure appeared unchanged. Fuel core diametral increases were small (up to 4%) and within the range previously observed on A1-61 wt % U 3 Si fuel irradiated in the NRU reactor. (author)

  5. Post irradiation examination of RAF/M steels after fast reactor irradiation up to 33 dpa and < 340 C (ARBOR1). RAFM steels. Metallurgical and mechanical characterisation. Final report for TW2-TTMS-001b, D9

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, C. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). EURATOM, Inst. fuer Materialforschung, Programm Kernfusion

    2010-07-01

    In an energy generating fusion reactor structural materials will be exposed to very high dpa-levels of about 100 dpa. Due to this fact and because fast reactor irradiation facilities in Europe are not available anymore, a reactor irradiation at the State Scientific Center of the Russian Federation with its Research Institute of Atomic Reactors (SSC RIAR), Dimitrovgrad, had been performed in the fast reactor BOR 60 with an instrumented test rig. This test rig contained tensile, impact and Low Cycle Fatigue type specimens used at FZK since many years. Samples of actual Reduced Activation Ferritic/Martensitic (RAF/M) -steels (e.g. EUROFER 97) had been irradiated in this reactor at a lower temperature (< 340 C) up to a damage of 33 dpa. This irradiation campaign was called ARBOR 1. Starting in 2003 one half of these irradiated samples were post irradiation examined (PIE) by tensile testing, low cycle fatigue testing and impact testing under the ISTC Partner Contract 2781p in the hot cells of SSC RIAR. In the post irradiation instrumented impact tests a significant increase in the Ductile to Brittle Transition Temperature as an effect of irradiation has been detected. During tensile testing the strength values are increasing and the strain values reduced due to substantial irradiation hardening. The hardening rate is decreasing with increasing damage level, but it does not show saturation. The low cycle fatigue behaviour of all examined RAF/M - steels show at total strain amplitudes below 1 % an increase of number of cycles to failure, due to irradiation hardening. From these post irradiation experiments, like tensile, low cycle fatigue and impact tests, radiation induced design data, e.g. for verification of design codes, can be generated.

  6. Protective Effect of Exogenous Dehydro-epiandrosterone Sulfate (DHEAS) on Liver Cell Organs of Whole Body y-Irradiated Rats

    International Nuclear Information System (INIS)

    Abdel-Fattah, K.I.; El-Gawish, M.A.; Abou-Safi, H.M.

    2005-01-01

    Dehydroepiandrosterone (DHEA) and its sulfate (DHES) are adrenal hormones. They are powerful endogenous antioxidants and are important in protecting the cells from damage. The present work aimed to evaluate the exogenous DHEAS as a protector against the whole body exposure to gamma radiation damages on DNA and RNA content of the nuclear fraction, calcium and acid phosphatase in the mitochondria fraction and glutathione (GSH) and malonaldehyde (MDA) in the cytosol fraction in the liver of male rats. Fifty male albino rats weighing 130-150 g were categorized into the following groups: 1-Control untreated. 2-Exposed to whole body gamma irradiation (6.5 Gy). 3-Received a single oral administration of DHEAS at a dose level of 200 mg/kg b.wt. 4-Administered with DHEAS (200 mg/kg) two h pre-exposure to whole body gamma irradiation (6.5 Gy). Three time intervals were determined for tissue sampling: after one day, one week and two weeks post irradiation (groups 2 and 4) and post administration of DHEAS (group 3). The results showed that: 1- DHEAS has a radioprotective effect on DNA and RNA content decreases in the liver nuclear fraction. 2- It significantly ameliorated the changes in mitochondria Ca21 content and acid phosphatase activity. 3- It improved both GSH and MDA contents in the cytosolic fraction. It could be concluded that, DHEAS showed an obvious protective role against the hazard of gamma radiation on liver cells. Several mechanisms were discussed about its effects. Therefore, more investigations are needed to understand well the role of DHEAS in protecting the animal tissues against ionizing radiation hazard

  7. POST-IRRADIATION ANALYSES OF U-MO DISPERSION FUEL RODS OF KOMO TESTS AT HANARO

    Directory of Open Access Journals (Sweden)

    H.J. RYU

    2013-12-01

    Full Text Available Since 2001, a series of five irradiation test campaigns for atomized U-Mo dispersion fuel rods, KOMO-1, -2, -3, -4, and -5, has been conducted at HANARO (Korea in order to develop high performance low enriched uranium dispersion fuel for research reactors. The KOMO irradiation tests provided valuable information on the irradiation behavior of U-Mo fuel that results from the distinct fuel design and irradiation conditions of the rod fuel for HANARO. Full size U-Mo dispersion fuel rods of 4–5 g-U/cm3 were irradiated at a maximum linear power of approximately 105 kW/m up to 85% of the initial U-235 depletion burnup without breakaway swelling or fuel cladding failure. Electron probe microanalyses of the irradiated samples showed localized distribution of the silicon that was added in the matrix during fuel fabrication and confirmed its beneficial effect on interaction layer growth during irradiation. The modifications of U-Mo fuel particles by the addition of a ternary alloying element (Ti or Zr, additional protective coatings (silicide or nitride, and the use of larger fuel particles resulted in significantly reduced interaction layers between fuel particles and Al.

  8. Radio protective effects of selenium on rats

    International Nuclear Information System (INIS)

    Bakir, A.; Alya, G

    2005-11-01

    Potential radio-protective effects of different selenium supplement concentrations of 4, 8, 15 and 30 ppm were evaluated in rats. Four groups of rats were administered different concentrations of selenium in drinking water for 30 days before irradiation starting from the ablactation which considered as day 0. The results showed that the sodium selenite of 4 ppm and 8 ppm enhance the 30-day survival of irradiated rats at 7 Gy ( sup 6 sup 0 Co source, whole body irradiation dose rate of 1 Gy x min sup - sup 1) compared to the control group. The mean cumulated probability of survival of rats was 69%+-6 (mean+-S.E.) and 77%+-6 in 4 and 8 ppm groups, respectively, versus 42%+-9 for control group (P<0.001). It was also indicated that sodium selenite with concentrations of 15 and 30 ppm had no significant reduction in mortality. The mean cumulated probability of survival of rats was 50%+-12 (P=0.39) and 49%+-14 (P=0.04), respectively. The toxic effects of selenium were observed at 15 ppm and 30 ppm, survivals after 30 days of selenium intake were 76% and 46%, respectively. It was concluded that 4 and 8 ppm sodium selenite have a radio-protective effect. 15 and 30 ppm sodium selenite had no radio-protective effects in rats, this may be due to a synergism of toxicity and radiation effects. (author)

  9. Hot Cell Post-Irradiation Examination and Poolside Inspection of Nuclear Fuel. Proceedings of the IAEA-HOTLAB Technical Meeting

    International Nuclear Information System (INIS)

    2013-04-01

    The growing operational requirements for nuclear fuel, such as longer fuel cycles, higher burnups and wider use of transient regimes, require more robust fuel designs and more radiation resistant materials. Development of such advanced fuels is only possible with testing and analysis of their performance and application of adequate post-irradiation examination (PIE) methods and techniques. In addition, operational feedback data from poolside and PIE facilities are absolutely necessary for verification of fuel modelling codes and analysis of fuel failure mechanisms. For these reasons, the International Atomic Energy Agency (IAEA) has supported the international exchange of knowledge and sharing of best practices in the application of modern destructive and non-destructive methods of investigation of highly radioactive materials through a series of technical meetings (TMs), the last of which was held in 2006 in Buenos Aires. Since 1963, similar meetings, initially at the European level, have been organized by the Hot Laboratories and Remote Handling Working Group (HOTLAB), a partner in the development of the IAEA's Post Irradiation Examination Facilities Database (PIEDB), part of the IAEA's Integrated Nuclear Fuel Cycle Information System. With this successful partnership in mind, in 2010 the IAEA Technical Working Group on Fuel Performance and Technology recommended that a joint IAEA-HOTLAB TM be held on 'Hot Cell Post-Irradiation Examination and Pool-Side Inspection of Nuclear Fuel', covering questions relevant to the IAEA sub-programmes on 'Nuclear Power Reactor Fuel Engineering' and 'Management of Spent Fuel from Nuclear Power Reactors'. The TM was held on 23-27 May 2011, in Smolenice, Slovakia, with the participation of a large number of interested organizations and comprehensive coverage of major PIE and poolside inspection issues relating to both operation and storage of fuel for nuclear power reactors. The proceedings, summaries and conclusions of that joint

  10. Radio protective effects of some medicinal plants

    International Nuclear Information System (INIS)

    Barupal, G.K.

    2012-01-01

    Many plants are known to have beneficial therapeutic effects as noted in the traditional Indian system of medicine, Ayurveda and used since time immemorial for curing diseases. Even today, nearly 70% of the world's population is dependent on plants for handling their health related problems and plants have been utilized successfully for the treatment of free radical-mediated diseases in human such as Rheumatoid arthritis, Atherosclerosis, Cancer, Alzheimer's disease, Parkinson's disease, aging and several other conditions including inflammatory diseases. Plant extracts eliciting radio protective efficacy contain a plethora of compounds including antioxidants, immunostimulants, cell proliferation stimulators, anti-inflammatory and antimicrobial agent, some of which may act in isolation as well as in combination with other constituents from the same plants. Glycyrrhiza glabra, Allium sepa, Allium sativum, Aloe arborescens, Amaranthus paniculatus, Curcuma longa, Moringa olefera and Syzygium cumini are some important radio protective plants. Alium sativum has been reported to possess antioxidant antimicrobial, antitumor, antimutagenic and anti-inflammatory properties. Aloe arborescens acts as a cell proliferate, healer and allergy reducer. Amaranthus paniculatus is used for purifying blood and treating scrofulous sores. Curcuma longa is widely used in antitumor and antibacterial activities. Leaf extract of Moringa oleifera is significantly used in nervous debility and healing of wound. Chlorella is well known nutrient dense superfood that contains 60% protein, 18 amino acids (including all the essential amino acids), more than 20 vitamins and minerals. Chlorell has been used to treat cancer and also protect the body from the effects of cancer radiation treatment due to its chlorophyll in abundance level. However they have little attention for their radio protective as well as antioxidant. There is an urgent need to develop newer, more efficient and reliable bioassays

  11. Validation of a continuous-energy Monte Carlo burn-up code MVP-BURN and its application to analysis of post irradiation experiment

    International Nuclear Information System (INIS)

    Okumura, Keisuke; Mori, Takamasa; Nakagawa, Masayuki; Kaneko, Kunio

    2000-01-01

    In order to confirm the reliability of a continuous-energy Monte Carlo burn-up calculation code MVP-BURN, it was applied to the burn-up benchmark problems for a high conversion LWR lattice and a BWR lattice with burnable poison rods. The results of MVP-BURN have shown good agreements with those of a deterministic code SRAC95 for burn-up changes of infinite neutron multiplication factor, conversion ratio, power distribution, and number densities of major fuel nuclides. Serious propagation of statistical errors along burn-up was not observed even in a highly heterogeneous lattice. MVP-BURN was applied to the analysis of a post irradiation experiment for a sample fuel irradiated up to 34.1 GWd/t, together with SRAC95 and SWAT. It was confirmed that the effect of statistical errors of MVP-BURN on a burned fuel composition was sufficiently small, and it could give a reference solution for other codes. In the analysis, the results of the three codes with JENDL-3.2 agreed with measured values within an error of 10% for most nuclides. However, large underestimation by about 20% was observed for 238 Pu, 242m Am and 244 Cm. It is probable that these discrepancies are a common problem for most current nuclear data files. (author)

  12. INL Initial Input to the Mission Need for Advanced Post-Irradiation Examination Capability A Non-Major System Acquisition Project

    International Nuclear Information System (INIS)

    Tonc, Vince

    2010-01-01

    Consolidated and comprehensive post-irradiation examination (PIE) capabilities will enable the science and engineering understanding needed to develop the innovative nuclear fuels and materials that are critical to the success of the U.S. Department of Energy's (DOE) Office of Nuclear Energy (NE) programs. Existing PIE capabilities at DOE Laboratories, universities, and in the private sector are widely distributed, largely antiquated, and insufficient to support the long-range mission needs. In addition, DOE's aging nuclear infrastructure was not designed to accommodate modern, state-of-the-art equipment and instrumentation. Currently, the U.S. does not have the capability to make use of state-of-the-art technology in a remote, hot cell environment to characterize irradiated fuels and materials on the micro, nano, and atomic scale. This 'advanced PIE capability' to make use of state-of-the-art scientific instruments in a consolidated nuclear operating environment will enable comprehensive characterization and investigation that is essential for effectively implementing the nuclear fuels and materials development programs in support of achieving the U.S. DOE-NE Mission.

  13. Post-irradiation replication and repair in UV-irradiated cells of Proteus mirabilis depends on protein synthesis and a functioning rec+ gene

    International Nuclear Information System (INIS)

    Hofemeister, J.

    1977-01-01

    The amount of and the molecular weight of newly synthesized DNA (piDNA) as well as its repair after UV irradiation in excision-proficient strains of P.mirabilis and E.coli K12 have been compared. A fraction of post-replication repair (PRR) in P.mirabilis is found to be dependent on de novo protein synthesis after UV irradiation. Pre-irradiation by UV and pre-treatment with nalidixic acid increase the efficiency of post-irradiation replication and PRR even in the presence of chloramphenicol. An inducible repair function in P.mirabilis is supposed to stimulate post-irradiation replication and repair. (author)

  14. Post-irradiation replication and repair in uv-irradiated cells of Proteus mirabilis depends on protein synthesis and a functioning rec/sup +/ gene

    Energy Technology Data Exchange (ETDEWEB)

    Hofemeister, J [Akademie der Wissenschaften der DDR, Gatersleben. Zentralinstitut fuer Genetik und Kulturpflanzenforschung

    1977-02-28

    The amount of and the molecular weight of newly synthesized DNA (piDNA) as well as its repair after uv irradiation in excision-proficient strains of P.mirabilis and E.coli K12 have been compared. A fraction of post-replication repair (PRR) in P.mirabilis is found to be dependent on de novo protein synthesis after uv irradiation. Pre-irradiation by uv and pre-treatment with nalidixic acid increase the efficiency of post-irradiation replication and PRR even in the presence of chloramphenicol. An inducible repair function in P.mirabilis is supposed to stimulate post-irradiation replication and repair.

  15. Post-irradiation examinations of uranium-plutonium mixed nitride fuel irradiated in JMTR (89F-3A capsule)

    International Nuclear Information System (INIS)

    Iwai, Takashi; Nakajima, Kunihisa; Kikuchi, Hironobu; Arai, Yasuo; Kimura, Yasuhiko; Nagashima, Hisao; Sekita, Noriaki

    2000-03-01

    Two helium-bonded fuel pins filled with uranium-plutonium mixed nitride pellets were encapsulated in 89F-3A and irradiated in JMTR up to 5.5% FIMA at a maximum linear power of 73 kW/m. The capsule cooled for ∼5 months was transported to Reactor Fuel Examination Facility and subjected to non-destructive and destructive post irradiation examinations. Any failure was not observed in the irradiated fuel pins. Very low fission gas release rate of about 2 ∼ 3% was observed, while the diametric increase of fuel pin was limited to ∼0.4% at the position of maximum reading. The inner surface of cladding tube did not show any signs of chemical interaction with fuel pellet. (author)

  16. Applicability of Machine-Learning Enabled LIBS in Post Irradiation Nuclear Forensic Analysis of High Level Waste

    International Nuclear Information System (INIS)

    Onkongi, J.; Maina, D.; Angeyo, H.K.

    2017-01-01

    Nuclear Forensics seeks Information to determine; Chemical Composition, Routes of transit, Origin (Provenance) and Intended use. Post Irradiation/Post detonation NF In a post-detonation event could you get clues/signatures from glass debris, minute sample sizes? Nuclear Forensic Technique Should be State-of -the art that is Rapid, Non-invasive, Remote ability and Non-destructive. Laser Induced Breakdown Spectroscopy (LIBS) unlike other Analytic Techniques that require tedious sample preparations such as Dissolution, digestion & matrix removal, which generate additional nuclear wastes that require proper Procedures for handling, storage & ultimate disposal, LIBS overcomes these limitations. Utility of Machine Learning Techniques employed include; Artificial Neural Networks, ANN (Regression/Modelling), Principal component Analysis, PCA (Classification) and Support Vector Machine SVM (Comparative study/Classification Machine Learning coupled with LIBS gives a state of the art analytic method. Utility of the technic in safeguards security and non-proliferation

  17. Post-irradiation examinations of inert matrix nitride fuel irradiated in JMTR (01F-51A capsule)

    International Nuclear Information System (INIS)

    Iwai, Takashi; Nakajima, Kunihisa; Kikuchi, Hironobu; Honda, Junichi; Hatakeyama, Yuichi; Ono, Katsuto; Matsui, Hiroki; Arai, Yasuo

    2007-03-01

    A plutonium nitride fuel pin containing inert matrix such as ZrN and TiN was encapsulated in 01F-51A and irradiated in JMTR. Minor actinides are surrogated by plutonium. Average linear powers and burnups were 408W/cm, 30000MWd/t(Zr+Pu) [132000MWd/t-Pu] for (Zr,Pu)N and 355W/cm, 38000MWd/t(Ti+Pu) [153000MWd/t-Pu] for (TiN,PuN). The irradiated capsule was transported to Reactor Fuel Examination Facility and subjected to non-destructive and destructive post irradiation examinations. Any failure was not observed in the irradiated fuel pin. Very low fission gas release rate of about 1.6% was measured. The inner surface of cladding tube did not show any signs of chemical interaction with fuel pellet. (author)

  18. Applicability of Machine-Learning Enabled LIBS in Post Irradiation Nuclear Forensic Analysis of High Level Nuclear Waste

    International Nuclear Information System (INIS)

    Onkongi, J.; Maina, D.; Angeyo, H. K.

    2017-01-01

    Nuclear Forensics seeks Information to determine; Chemical Composition, Routes of transit, Origin (Provenance) and Intended use. Post Irradiation/Post detonation NF In a post-detonation event could you get clues/signatures from glass debris, minute sample sizes? Nuclear Forensic Technique Should be State-of -the art that is Rapid, Non-invasive, Remote ability and Non-destructive. Laser Induced Breakdown Spectroscopy (LIBS) unlike other Analytic Techniques that require tedious sample preparations such as Dissolution, digestion & matrix removal, which generate additional nuclear wastes that require proper Procedures for handling, storage & ultimate disposal, LIBS overcomes these limitations. Utility of Machine Learning Techniques employed include; Artificial Neural Networks, ANN (Regression/Modelling), Principal component Analysis, PCA (Classification) and Support Vector Machine SVM (Comparative study/Classification Machine Learning coupled with LIBS gives a state of the art analytic method. Utility of the technic in safeguards security and non-proliferation

  19. Post-irradiation hardness of resin-modified glass ionomer cements and a polyacid-modified composite resin

    International Nuclear Information System (INIS)

    Yap, A.U.J.

    1997-01-01

    This study examined the post-irradiation hardness of resin-modified glass ionomer cements and a polyacid-modified composite resin using a digital microhardness tester. Change in hardness of these materials over a period of 6 months was compared to that of conventional glass ionomer cements and a composite resin. With the exception of the composite resin, all materials showed a significant increase in hardness over 24 h after their initial set. Dual-cure resin-modified glass ionomer cements showed decreased hardness with increased storage time in saline at 37 o C. Results suggest that the addition of resins to glass ionomer cements does not improve initial hardness and does not negate the acid-base reaction of conventional cements. Resin addition may, however, lead to increased water sorption and decreased hardness. (author)

  20. Influence of UV Photo-Transfer on Post Irradiated Double Sulphate Poly-Crystals By Gamma And X-rays

    International Nuclear Information System (INIS)

    El-kolaly, M.A.

    2000-01-01

    Solid state thermoluminescence (TL) dosimetry has for many years been the pre-eminent method for quantifying ionizing radiation dose. In this work, thermoluminescence characteristics of the double sulphate (Li Cs So 4 ) poly-crystals have been studied after exposure to different doses from X and gamma radiation. The glue curves showed TL response of three peaks at 75,125,250 degree. The structure of the glue peaks due to X-rays is quite different from that due to gamma rays. UV exposure yields a regeneration of the TL peaks for the post irradiated samples for X or gamma radiation with some changes in the peaks structure especially the third peak. For the post X-ray irradiated crystals, the area under the third glow peak (III) increased linearly with the integrated time of UV exposures till about 30 min. after which no changes were observed; while , for the post gamma-irradiated crystals two linear regions were observed

  1. Temper embrittlement, irradiation induced phosphorus segregation and implications for post-irradiation annealing of reactor pressure vessels

    International Nuclear Information System (INIS)

    McElroy, R.J.; English, C.A.; Foreman, A.J.; Gage, G.; Hyde, J.M.; Ray, P.H.N.; Vatter, I.A.

    1999-01-01

    Three steels designated JPB, JPC and JPG from the IAEA Phase 3 Programme containing two copper and phosphorus levels were pre- and post-irradiation Charpy and hardness tested in the as-received (AR), 1200 C/0.5h heat treated (HT) and heat treated and 450 C/2000h aged (HTA) conditions. The HT condition was designed to simulate coarse grained heat-affected zones (HAZ's) and showed a marked sensitivity to thermal ageing in all three alloys. Embrittlement after thermal ageing was greater in the higher phosphorus alloys JPB and JPG. Charpy shifts due to thermal ageing of between 118 and 209 C were observed and accompanied by pronounced intergranular fracture, due to phosphorus segregation. The irradiation embrittlement response was complex. The low copper alloys, JPC and JPB, in the HT and HTA condition exhibited significant irradiation induced Charpy shift but very low or even negative hardness changes indicating non-hardening embrittlement. The higher copper alloy, JPG, also exhibited irradiation hardening in line with its copper content. Fractographic and microchemical studies indicated irradiation induced phosphorus segregation and a transition from cleavage to intergranular failure at grain boundary phosphorus concentrations above a critical level. The enhanced grain boundary phosphorus level increased with dose in agreement with a kinetic segregation model developed at Harwell. The relevance of the thermal ageing studies to RPV Annealing for Plant-Life Extension was identified early in the program. It is of concern that annealing of RPV's has been performed, or is proposed, at temperatures in the range 425--475 C for periods of about 1 week (168h). Much attention has been given to the use of in-situ hardness measurements and machining miniature Charpy and tensile specimens from belt-line plate and weld materials. However, HAZ's, often containing higher phosphorus levels than the present materials, have largely been ignored. A post-irradiation annealing (PIA

  2. Management of spent fuel from research and prototype power reactors and residues from post-irradiation examination of fuel

    International Nuclear Information System (INIS)

    1989-09-01

    The safe and economic management of spent fuel is important for all countries which have nuclear research or power reactors. It involves all aspects of the handling, transportation, storage, conditioning and reprocessing or final disposal of the spent fuel. In the case of spent fuel management from power reactors the shortage of available reprocessing capacity and the rising economic interest in the direct disposal of spent fuel have led to an increasing interest in the long term storage and management of spent fuel. The IAEA has played a major role in coordinating the national activities of the Member States in this area. It was against this background that the Technical Committee Meeting on ''Safe Management of Spent Fuel From Research Reactors, Prototype Power Reactors and Fuel From Commercial Power Reactors That Has Been Subjected to PIE (Post Irradiated Examination)'' (28th November - 1st December 1988) was organised. The aims of the current meeting have been to: 1. Review the state-of-the-art in the field of management of spent fuel from research and prototype power reactors, as well as the residues from post irradiation examination of commercial power reactor fuel. The emphasis was to be on the safe handling, conditioning, transportation, storage and/or disposal of the spent fuel during operation and final decommissioning of the reactors. Information was sought on design details, including shielding, criticality and radionuclide release prevention, heat removal, automation and remote control, planning and staff training; licensing and operational practices during each of the phases of spent fuel management. 2. Identify areas where additional research and development are needed. 3. Recommend areas for future international cooperation in this field. Refs, figs and tabs

  3. Effects of ventilation tunnel protection on stability

    Energy Technology Data Exchange (ETDEWEB)

    Strizhiboroda, S K; Kuritsyn, B I; Anosov, O S

    1983-09-01

    Analyzed are effects of strata control on a ventilation gate road situated at a depth of 860 m in a coal seam 0.65 m thick with dip angle of 48 degrees. The direct roof and floor consisted of limestone and the main roof of shales. The ventilation gate road with a cross section of 8.2 m/Sup 2/ was supported by the AP-9.2 arched steel supports. The following methods for gate road protection were used: timber cribbings, reinforced cribbings, strips of pneumatic stowing (using waste rocks), and coal support pillars. Effects of gate road protection on roof subsidence, subsidence rate and on support deformation in the gate road were analyzed considering strata control method and the distance to the advancing longwall face. The results of comparative evaluations, given in 4 diagrams, showed that timber cribbings guaranteed the most regular stress distribution and regular roof subsidence. Use of coal support pillars negatively influenced stress distribution. Irrespective of strata control method from 60 to 80% of roof subsidence occurred at a distance from 0 to 40 m behind a working face. Roof subsidence ranged from 17.3 to 38.3 mm/d when support pillars were used, was 27 mm/d when reinforced cribbings were used and ranged from 9.6 to 16.5 mm/d when pneumatic stowing was used. Use of blocks of reinforced concrete for protecting ventilation gate roads in inclined strata is recommended.

  4. Effects of eprosartan on target organ protection

    Directory of Open Access Journals (Sweden)

    Alejandro de la Sierra

    2006-03-01

    Full Text Available Alejandro de la SierraHypertension Unit, Department of Internal Medicine, Hospital Clínic, IDIBAPS, University of Barcelona, SpainAbstract: Hypertension is the most important cardiovascular risk factor for stroke. Blood pressure reduction by antihypertensive treatment is clearly efficacious in the prevention of stroke (both primary and secondary, although no clear differences have yet been observed between antihypertensive drug classes. However, a recent study reported the clear superiority of the angiotensin-receptor blocker eprosartan over the calcium channel blocker nitrendipine in cardiovascular protection of hypertensive patients with a previous stroke. Comparative studies using angiotensin-receptor blockers have also suggested the superiority of this class of drugs on primary stroke prevention. This effect may be linked to their beneficial actions on left ventricular hypertrophy, atrial enlargement, and supraventricular arrhythmias, endothelial dysfunction, inflammation, and remodelling, as well as a direct neuroprotective effect mediated through the stimulation of the angiotensin II type-2 receptor. In addition, a sympathoinhibition observed with the renin–angiotensin system blockers and particularly demonstrated with eprosartan, may help to explain the better cardiovascular and cerebrovascular protection in comparison with the calcium antagonist nitrendipine.Keywords: eprosartan, angiotensin-receptor blockers, hypertension, stroke, organ protection

  5. Radiation protective agents possessing anti-oxidative properties

    Energy Technology Data Exchange (ETDEWEB)

    Anzai, Kazunori; Ueno, Emi; Yoshida, Akira; Furuse, Masako; Ikota, Nobuo [National Inst. of Radiological Sciences, Research Center for Radiation Safety, Chiba, Chiba (Japan)

    2005-11-15

    The purpose of studies is to see mechanisms of radiation protection of agents possessing anti-oxidative properties because the initial step resulting in radiation hazard is the formation of radicals by water radiolysis. Agents were commercially available or synthesized proxyl derivatives (spin prove agents), commercially available spin-trapping agents, edaravone and TMG (a tocopherol glycoside). Mice and cultured cells were X-irradiated by Shimadzu Pantak HF-320 or 320S. Survivals of cells were determined by colony assay and of mice, to which the agents were given intraperitoneally before or after X-irradiation, within 30 days post irradiation. Plasma and marrow concentrations of proxyls were estimated by electron spin resonance (ESR) spectrometry. Mechanisms of their radiation protective effects were shown different from agent to agent. TMG was found effective even post irradiation, which suggests a possibility for a new drug development. Some (spin trapping agents and TMG), virtually ineffective at the cell level, were found effective in the whole body, suggesting the necessity of studies on their disposition and metabolism. (S.I.)

  6. Radiation protective agents possessing anti-oxidative properties

    International Nuclear Information System (INIS)

    Anzai, Kazunori; Ueno, Emi; Yoshida, Akira; Furuse, Masako; Ikota, Nobuo

    2005-01-01

    The purpose of studies is to see mechanisms of radiation protection of agents possessing anti-oxidative properties because the initial step resulting in radiation hazard is the formation of radicals by water radiolysis. Agents were commercially available or synthesized proxyl derivatives (spin prove agents), commercially available spin-trapping agents, edaravone and TMG (a tocopherol glycoside). Mice and cultured cells were X-irradiated by Shimadzu Pantak HF-320 or 320S. Survivals of cells were determined by colony assay and of mice, to which the agents were given intraperitoneally before or after X-irradiation, within 30 days post irradiation. Plasma and marrow concentrations of proxyls were estimated by electron spin resonance (ESR) spectrometry. Mechanisms of their radiation protective effects were shown different from agent to agent. TMG was found effective even post irradiation, which suggests a possibility for a new drug development. Some (spin trapping agents and TMG), virtually ineffective at the cell level, were found effective in the whole body, suggesting the necessity of studies on their disposition and metabolism. (S.I.)

  7. Protective effect by EDTA in radiation inactivation of enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Kumakura, M; Kaetsu, I

    1985-11-05

    Protective effect by EDTA in radiation inactivation of enzymes such as glucoamylase, cellulase, and urease was studied. A remarkable protective effect by EDTA was observed and had a maximum at certain EDTA concentration. The protective effect was compared with other protective agents in the irradiation of urease, in which the protective ability of EDTA was greater than those of sulfhydryl compounds such as cysteine. (author).

  8. Differential post-irradiation caffeine response in normal diploid versus SV40-transformed human fibroblasts: potential role of nuclear organization and protein-composition

    International Nuclear Information System (INIS)

    Taylor, Y.C.; Parsian, A.J.; Duncan, P.G.

    1993-01-01

    To test the hypothesis that the enhancement of cell killing by post-irradiation treatment with caffeine (CAF) is mediated by alterations in chromatin structure, several nuclear parameters were examined in both caffeine-responsive and non-responsive cell lines. (author)

  9. Differential post-irradiation caffeine response in normal diploid versus SV40-transformed human fibroblasts: potential role of nuclear organization and protein-composition

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Y.C.; Parsian, A.J.; Duncan, P.G. (Washington Univ., St. Louis, MO (United States). School of Medicine)

    1993-07-01

    To test the hypothesis that the enhancement of cell killing by post-irradiation treatment with caffeine (CAF) is mediated by alterations in chromatin structure, several nuclear parameters were examined in both caffeine-responsive and non-responsive cell lines. (author).

  10. The post irradiation examination of a sphere-pac (UPu)C fuel pin irradiated in the BR-2 reactor (MFBS 7 experiment)

    International Nuclear Information System (INIS)

    Smith, L.; Aerne, E.T.; Buergisser, B.; Flueckiger, U.; Hofer, R.; Petrik, F.

    1979-09-01

    A pin fuelled with Swiss made (UPu)C microspheres has been successfully irradiated to a peak burn-up of 6% fima in the Belgian BR2 Reactor. The pin, rated up to 95 kW/m, was intact after irradiation and exhibited a peak strain of just over 0.5%. The results of the post irradiation examination are reported. (Auth.)

  11. Protective Effects of Ginseng on Neurological Disorders

    Directory of Open Access Journals (Sweden)

    Wei-Yi eOng

    2015-07-01

    Full Text Available Ginseng (Order: Apiales, Family: Araliaceae, Genus: Panax has been used as a traditional herbal medicine for over 2000 years, and is recorded to have antianxiety, antidepressant and cognition enhancing properties. The protective effect of ginseng on neurological disorders is discussed in this review. Ginseng species and ginsenosides, and their intestinal metabolism and bioavailability are briefly introduced. This is followed by molecular mechanisms of effects of ginseng on the brain, including glutamatergic transmission, monoamine transmission, estrogen signaling, nitric oxide production, the Keap1/Nrf2 adaptive cellular stress pathway, neuronal survival, apoptosis, neural stem cells and neuroregeneration, microglia, astrocytes, oligodendrocytes and cerebral microvessels. The molecular mechanisms of the neuroprotective effects of ginseng in Alzheimer’s disease including Aβ formation, tau hyperphosphorylation and oxidative stress, major depression, stroke, Parkinson’s disease and multiple sclerosis / experimental allergic encephalitis are then presented. It is hoped that this discussion will stimulate more studies on the use of ginseng in these disorders.

  12. DNA microarray analyses reveal a post-irradiation differential time-dependent gene expression profile in yeast cells exposed to X-rays and gamma-rays.

    Science.gov (United States)

    Kimura, Shinzo; Ishidou, Emi; Kurita, Sakiko; Suzuki, Yoshiteru; Shibato, Junko; Rakwal, Randeep; Iwahashi, Hitoshi

    2006-07-21

    Ionizing radiation (IR) is the most enigmatic of genotoxic stress inducers in our environment that has been around from the eons of time. IR is generally considered harmful, and has been the subject of numerous studies, mostly looking at the DNA damaging effects in cells and the repair mechanisms therein. Moreover, few studies have focused on large-scale identification of cellular responses to IR, and to this end, we describe here an initial study on the transcriptional responses of the unicellular genome model, yeast (Saccharomyces cerevisiae strain S288C), by cDNA microarray. The effect of two different IR, X-rays, and gamma (gamma)-rays, was investigated by irradiating the yeast cells cultured in YPD medium with 50 Gy doses of X- and gamma-rays, followed by resuspension of the cells in YPD for time-course experiments. The samples were collected for microarray analysis at 20, 40, and 80 min after irradiation. Microarray analysis revealed a time-course transcriptional profile of changed gene expressions. Up-regulated genes belonged to the functional categories mainly related to cell cycle and DNA processing, cell rescue defense and virulence, protein and cell fate, and metabolism (X- and gamma-rays). Similarly, for X- and gamma-rays, the down-regulated genes belonged to mostly transcription and protein synthesis, cell cycle and DNA processing, control of cellular organization, cell fate, and C-compound and carbohydrate metabolism categories, respectively. This study provides for the first time a snapshot of the genome-wide mRNA expression profiles in X- and gamma-ray post-irradiated yeast cells and comparatively interprets/discusses the changed gene functional categories as effects of these two radiations vis-à-vis their energy levels.

  13. Protective effects of ischemic postconditioning on intestinal

    Directory of Open Access Journals (Sweden)

    DING Jun-tao

    2011-04-01

    Full Text Available 【Abstract】Objective: To explore the protective effects of two types of ischemic postconditioning (IP on intestinal mucosa barrier in rabbits with crush injury of the hind limb. Methods: This study was conducted between August and December 2008 in the Department of Trauma Surgery, Daping Hospital, Third Military Medical University, Chongqing, China. The model of crush injury to the hind limb of rabbits was firstly developed by a 25 kg object with the right hind limbs fixed by wooden splints, and then two types of IP were established, including occluding/opening the common iliac artery and vein alternatively (traditional IP, IP A and binding/loosening the proximum of the injured hind limb alternatively (modified IP, IP B. Thirty-six male New Zealand white rabbits were randomly divided into three groups: IP A group, IP B group and control group, with 12 rabbits in each group. The serum levels of diamine oxidase (DAO and intestinal fatty acid-binding protein (I-FABP were detected at 2, 6, 12 and 24 hours after injury. Pathological changes of ileum were examined at 24 hours after injury. Results: The serum levels of I-FABP at 2, 6, 12 and 24 hours after injury in both IP A and IP B groups had a significant decrease, compared with control group. DAO levels also showed the same change trend at 2 and 6 hours after injury, but showed no significant difference between two IP groups. No difference in pathological changes of ileum was found among the three groups. Conclusions: IP can protect intestinal mucosa barrier function on the model of hind limb crush injury in rabbits. Meanwhile the modified IP B shows the same protection as the traditional IP A, and is worth applying in clinic. Key words: Ischemic postconditioning; Crush syndrome; Intestinal mucosa

  14. Corrosion and protection in reinforced concrete : Pulse cathodic protection: an improved cost-effective alternative

    NARCIS (Netherlands)

    Koleva, D.A.

    2007-01-01

    Corrosion and protection in reinforced concrete. Pulse cathodic protection: an improved cost-effective alternative. The aim of the research project was to study the possibilities for establishing a new or improved electrochemical method for corrosion prevention/protection for reinforced concrete.

  15. Post-irradiation creep properties of four plates and two forgings DIN 1.4948 steel from the SNR-300 permanent primary structures

    International Nuclear Information System (INIS)

    Schaaf, B. van der.

    1987-01-01

    The safety authorities, involved in the licensing procedure of the SNR-300, have required the determination of the irradiation effect on the heat-to-heat variation of tensile and creep properties of Werkst. No. DIN 1.4948 austenitic stainless steel. These data are lacking in the present codes and they are necessary for the design and safety considerations of the permanent structures. Results are presented of about 200 tests on irradiated and unirradiated material of 6 heats used in the production of the SNR-300 permanent structures. After irradiation in the HFR-Petten to neutron fluences relevant for the SNR-300 service conditions post-irradiation tensile and creep tests (up to 10,000 hrs rupture time) were performed in the temperature range 723 K to 923 K. All heats are embrittled by irradiation resulting in reduction of rupture times, creep strength and ultimate tensile strength. The considerable reduction is attributed to helium enhanced intergranular creep crack growth, which reduces the ductility and strength, but does not affect the creep rate. The variation of tensile and creep properties is large and independent of irradiation. The minimum derived creep strength in irradiated condition drops below the values expected in the ASME Code and VdTuV Blatt. In design and safety analyses the irradiation effect on creep properties must be accounted for with an appropriate reduction factor. The predictions given, have to be verified with long-term creep tests and parts of the SNR surveillance programme. 172 figs.; 17 refs.; 58 tables

  16. Accounting for biological effectiveness in radiological protection

    International Nuclear Information System (INIS)

    Dennis, J.A.

    1989-01-01

    Relative biological effectiveness (RBE) presents a practical problem to radiological protection when attempts are made to ensure that the assessed risks from different types of radiation and different modes of exposure to radiation are commensurate with one another. Unfortunately, the theoretical understanding of RBE is still in the stage of competing explanations and hypotheses. Furthermore, the division of the concept of dose equivalent into a set of concepts for risk assessment and another set for measurement and control has introduced conflicting requirements of a practical nature that are difficult to resolve. Many of those working in radiobiology and radiation protection have perceived the need to increase the quality factors for photon and neutron radiations. It may be more reasonable to change the quality factors for neutrons than for other radiations. The advantages and disadvantages of different methods for accommodating such changes within the dose-equivalent concepts are to be examined. The method of accommodating such a change that has the least practical disadvantages is to increase the quality factors for all secondary particles produced in tissue by neutron radiations by a constant factor. The only disadvantage would be the perception that the quality factors for these secondary particles were not treated in a consistent fashion for all types of ionising radiation. (author)

  17. Post-irradiation treatment with OK432 can prevent radiation-induced bone marrow death

    International Nuclear Information System (INIS)

    Kurishita, A.; Uehara, Y.; Tohoku Univ., Sendai; Katoh, H.; Hirose, S.; Uchida, A.; Mizutani, Y.; Okada, S.; Ono, T.

    1991-01-01

    The radioprotective effect of OK432, a Streptocuccus haemolyticus preparation, on bone marrow death was examined in mice. The LD 50 value was increased from 7.55 Gy in controls to 8.45 Gy in mice treated once with OK432 immediately after irradiation. Multiple administration of the agent further elevated the LD 50 value to 9.56 Gy. The radioprotective effect was also apparent when multiple treatments were commenced as late as 72 h after irradiation. (author)

  18. Stability of the post irradiation traps in LiF: Mg, Cu, P

    International Nuclear Information System (INIS)

    Gonzalez, P.R.; Furetta, C.; Azorin, J.

    2004-01-01

    In this work the results of the study of the stability of the traps are presented in dosemeters Tl of LiF: Mg,Cu,P, irradiated with gamma radiation of 60 Co. The studied dosemeters were of LiF: Mg,Cu,P + Ptfe, developed in the ININ, taking like reference to the commercial dosemeter GR200A of Chinese manufacture. Before being exposed to the radiation, the dosemeters received their standard treatment from having erased, two hours after the irradiation they took the initial readings. The dosemeters faded again and they were irradiated to the same dose, soon after they stayed under normal conditions, protected of the light, later on they were taken their readings periodically during six months. The readings taken Tl the same day of the irradiation presented four peaks whose energy, determined by the deconvolution method were; 1.30 ± 0.01 eV, 1.50 ± 0.01 eV, 1.70 ± 0.01 eV and 2.58 ± 0.02 eV, for LiF: Mg,Cu,P + Ptfe, while GR200A stops the energy they were: 1.33 ± 0.11 eV, 1.58 ± 0.11 eV, 1.73 ± 0.11 eV and 2.60 ± 0.03 eV. In both cases the peak 1, with the energy but it lowers, it disappears completely after some later hours to the irradiation, while the peak 2, it disappears completely after 122 days for the local dosemeter and after 94 days for the commercial dosemeter. The energy of the peaks 3 and 4 that remained visible during the whole period of study it was: 1.38 ± 0.01 eV and 2.65 ± 0.01 eV, for LiF: Mg,Cu,P + Ptfe respectively, in the same order for GR200A, the energies were: 1.51 ± 0.02 eV and 2.64 ± 0.03 eV. In all the cases the peaks with energy below 2 eV, showed tendency to the drop, while the main peak, showed certain tendency to increase, as they show it the results. (Author)

  19. The post irradiation examination of three fuel rods from the IFA 429 experiment irradiated in the Halden Reactor

    International Nuclear Information System (INIS)

    Williams, J.

    1979-11-01

    A series of fuel rod irradiation experiments were performed in the Halden Heavy Boiling Water Reactor in Norway. These were designed to provide a range of fuel property data as a function of burn-up. One of these experiments was the IFA-429. This was designed to study the absorption of helium filling gas by the UO 2 fuel pellets, steady state and transient fission gas release and fuel thermal behaviour to high burn-up. This data was to be obtained as a function of fuel density, fuel grain size, initial fuel/cladding gap, average linear heat rating, burn-up and overpower transients. All the fuel is in the form of pressed and sintered UO 2 pellets enriched to 13 weight percent 235 U. All the rods were clad in Zircaloy 4 tube. The details of the experiment are given. The post irradiation examination included: visual examination, neutron radiography, dimensional measurements, gamma scanning, measurement of gases in fuel rods and internal free volume, burn-up analysis, metallographic examination, measurement of retained gas in UO 2 pellets, measurement of bulk density of UO 2 . The results are given and discussed. (U.K.)

  20. Post-irradiation examination of prototype Al-64 wt% U3Si2 fuel rods from NRU

    International Nuclear Information System (INIS)

    Sears, D.F.; Primeau, M.F.; Buchanan, C.; Rose, D.

    1997-01-01

    Three prototype fuel rods containing Al-64 wt% U 3 Si 2 (3.15 gU/cm 3 ) have been irradiated to their design burnup in the NRU reactor without incident. The fuel was fabricated using production-scale equipment and processes previously developed for Al-U 3 Si fuel fabrication at Chalk River Laboratories, and special equipment developed for U 3 Si 2 powder production and handling. The rods were irradiated in NRU up to 87 at% U-235 burnup under typical driver fuel conditions; i.e., nominal coolant inlet temperature 37 degrees C, inlet pressure 654 kPa, mass flow 12.4 L/s, and element linear power ratings up to 73 kW/m. Post-irradiation examinations showed that the fuel elements survived the irradiation without defects. Fuel core diametral increases and volumetric swelling were significantly lower than that of Al-61 wt% U 3 Si fuel irradiated under similar conditions. This irradiation demonstrated that the fabrication techniques are adequate for full-scale fuel manufacture, and qualified the fuel for use in AECL's research reactors

  1. Evolution of the radiation-induced defect structure in 316 type stainless steel after post-irradiation annealing

    Energy Technology Data Exchange (ETDEWEB)

    Van Renterghem, W., E-mail: wvrenter@sckcen.be; Konstantinović, M.J., E-mail: mkonstan@sckcen.be; Vankeerberghen, M., E-mail: mvankeer@sckcen.be

    2014-09-15

    Highlights: • TEM study of irradiated CW316 steel after post-irradiation annealing. • Frank loops were removed after annealing at 550 °C, by unfaulting and growing. • The cavity density decreases after annealing at 550 °C, but not completely removed. • Frank loop and cavity removal is controlled by the annealing temperature. • The dissolution of γ' precipitates is controlled by the iron diffusion length. - Abstract: The thermal stability of Frank loops, black dots, cavities and γ′ precipitates in an irradiated 316 stainless steel was studied by transmission electron microscopy. The samples were retrieved from a thimble tube irradiated at around 320 °C up to 80 dpa in a commercial nuclear power reactor, and thermally annealed, varying both annealing temperature and time. With increasing annealing temperature the density of all defects gradually decreased, resulting in the complete removal of Frank loops at 550 °C. In contrast to other defects, the density of the γ′ precipitates sharply decreased with increasing annealing time, which indicates that the dissolution of the γ′ precipitates is governed by the iron diffusion length.

  2. A case of divided latissimus dorsi flap repair for chest wall defect after wide resection of post-irradiation angiosarcoma

    International Nuclear Information System (INIS)

    Matsubara, Yukiko; Sawaizumi, Masayuki; Imai, Tomohiro; Maeda, Takuma; Fujita, Kazutoshi; Matsumoto, Seiichi; Iwase, Takuji; Motoi, Noriko; Kanda, Hiroaki

    2011-01-01

    We report the case of a 76-year-old woman who had undergone breast-conserving surgery for left breast cancer, followed by irradiation at a total dose of 66 Gy in 2005. When 5 years 1 month had elapsed after the operation, redness of the left chest wall was observed. A biopsy was performed and the histopathological diagnosis was angiosarcoma. Extended resection of the full thickness of the skin was performed. Adequate resection left a massive defect 15 x 18 cm in size. The divided latissimus dorsi flap was designed, and the oval-shaped skin defect was closed with the skin island of this flap. Post-irradiation sarcoma involving the vessels is a rare entity and occurs in 0.07-0.48% of all cases after radiation therapy. It metastasizes to the distant organs in an early stage and has a poor prognosis. No standard therapy for the disease has been established. Early detection and extended resection are considered to contribute to improvement of the prognosis. The divided latissimus dorsi flap is very useful for reconstructing a wide chest wall defect without the need to wide skin graft the donor site. (author)

  3. Post irradiation characterization of beryllium and beryllides after high temperature irradiation up to 3000 appm helium production in HIDOBE-01

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, A.V., E-mail: fedorov@nrg.eu [Nuclear Research and Consultancy Group, Westerduinweg 3, Postbus 25, Petten, 1755 ZG (Netherlands); Til, S. van; Stijkel, M.P. [Nuclear Research and Consultancy Group, Westerduinweg 3, Postbus 25, Petten, 1755 ZG (Netherlands); Nakamichi, M. [Japan Atomic Energy Agency, Rokkasho (Japan); Zmitko, M. [The European Joint Undertaking for ITER and the Development of Fusion Energy, c/ Josep Pla, n° 2, Torres Diagonal Litoral, Edificio B3, Barcelona 08019 (Spain)

    2016-01-15

    Titanium beryllides are considered as advanced candidate material for neutron multiplier for the helium cooled pebble bed (HCPB) and/or the water cooled ceramic breeder (WCCB) breeder blankets. In the HIDOBE-01 (HIgh DOse irradiation of BEryllium) experiment, beryllium and beryllide pellets with 5 at% and 7 at% Ti are irradiated at four different target temperatures (T{sub irr}): 425 °C, 525 °C, 650 °C and 750 °C up to the dose corresponding to 3000 appm He production in beryllium. The pellets were supplied by JAEA. During post irradiation examinations the critical properties of volumetric swelling and tritium retention were studied. Both titanium beryllide grades show significantly less swelling than the beryllium grade, with the difference increasing with the irradiation temperature. The irradiation induced swelling was studied by using direct dimensions. Both beryllide grades showed much less swelling as compare to the reference beryllium grade. Densities of the grades were studied by Archimedean immersion and by He-pycnometry, giving indications of porosity formation. While both beryllide grades show no significant reduction in density at all irradiation temperatures, the beryllium density falls steeply at higher T{sub irr}. Finally, the tritium release and retention were studied by temperature programmed desorption (TPD). Beryllium shows the same strong tritium retention as earlier observed in studies on beryllium pebbles, while the tritium inventory of the beryllides is significantly less, already at the lowest T{sub irr} of 425 °C.

  4. Post-irradiation examination of U3SIX-AL fuel element manufactured and irradiated in Argentina

    International Nuclear Information System (INIS)

    Ruggirello, Gabriel; Calabroni, Hector; Sanchez, Miguel; Hofman, Gerard

    2002-01-01

    As a part of CNEA's qualification program as a supplier of low enriched Al-U 3 Si 2 dispersion fuel elements for research reactors, a post irradiation examination (PIE) of the first prototype of this kind, called P-04, manufactured and irradiated in Argentina, was carried out. The main purpose of this work was to set up various standard PIE techniques in the hot cell, looking forward to the next steps of the qualification program, as well as to acquire experience on the behaviour of this nuclear material and on the control of the manufacturing process. After an appropriate cooling period, on May 2000 the P-04 was transported to the hot cell in Ezeiza Atomic Centre. Non destructive and destructive tests were performed following the PIE procedures developed in Argonne National Laboratory (ANL), this mainly included dimensional measurement, microstructural observations and chemical burn-up analyses. The methodology and results of which are outlined in this report. The results obtained show a behaviour consistent with that of other fuel elements of the same kind, tested previously. On the other hand the results of this PIE, specially those concerning burn-up analysis and stability and corrosion behaviour of the fuel plates, will be of use for the IAEA Regional Program on the characterization of MTR spent fuel. (author)

  5. Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert; Gao, Fei; Sun, Xin; Tonks, Michael; Biner, Bullent; Millet, Paul; Tikare, Veena; Radhakrishnan, Balasubramaniam; Andersson , David

    2012-04-11

    A study was conducted to evaluate the capabilities of different numerical methods used to represent microstructure behavior at the mesoscale for irradiated material using an idealized benchmark problem. The purpose of the mesoscale benchmark problem was to provide a common basis to assess several mesoscale methods with the objective of identifying the strengths and areas of improvement in the predictive modeling of microstructure evolution. In this work, mesoscale models (phase-field, Potts, and kinetic Monte Carlo) developed by PNNL, INL, SNL, and ORNL were used to calculate the evolution kinetics of intra-granular fission gas bubbles in UO2 fuel under post-irradiation thermal annealing conditions. The benchmark problem was constructed to include important microstructural evolution mechanisms on the kinetics of intra-granular fission gas bubble behavior such as the atomic diffusion of Xe atoms, U vacancies, and O vacancies, the effect of vacancy capture and emission from defects, and the elastic interaction of non-equilibrium gas bubbles. An idealized set of assumptions was imposed on the benchmark problem to simplify the mechanisms considered. The capability and numerical efficiency of different models are compared against selected experimental and simulation results. These comparisons find that the phase-field methods, by the nature of the free energy formulation, are able to represent a larger subset of the mechanisms influencing the intra-granular bubble growth and coarsening mechanisms in the idealized benchmark problem as compared to the Potts and kinetic Monte Carlo methods. It is recognized that the mesoscale benchmark problem as formulated does not specifically highlight the strengths of the discrete particle modeling used in the Potts and kinetic Monte Carlo methods. Future efforts are recommended to construct increasingly more complex mesoscale benchmark problems to further verify and validate the predictive capabilities of the mesoscale modeling

  6. SU-E-T-628: Predicted Risk of Post-Irradiation Cerebral Necrosis in Pediatric Brain Cancer Patients: A Treatment Planning Comparison of Proton Vs. Photon Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Freund, D [Willis Knighton Cancer Center, Shreveport, LA (United States); Zhang, R; Sanders, M [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Newhauser, W [Louisiana State University, Baton Rouge, LA (United States)

    2015-06-15

    Purpose: Post-irradiation cerebral necrosis (PICN) is a severe late effect that can Result from brain cancers treatment using radiation therapy. The purpose of this study was to compare the treatment plans and predicted risk of PICN after volumetric modulated arc therapy (VMAT) to the risk after passively scattered proton therapy (PSPT) and intensity modulated proton therapy (IMPT) in a cohort of pediatric patients. Methods: Thirteen pediatric patients with varying age and sex were selected for this study. A clinical treatment volume (CTV) was constructed for 8 glioma patients and 5 ependymoma patients. Prescribed dose was 54 Gy over 30 fractions to the planning volume. Dosimetric endpoints were compared between VMAT and proton plans. The normal tissue complication probability (NTCP) following VMAT and proton therapy planning was also calculated using PICN as the biological endpoint. Sensitivity tests were performed to determine if predicted risk of PICN was sensitive to positional errors, proton range errors and selection of risk models. Results: Both PSPT and IMPT plans resulted in a significant increase in the maximum dose and reduction in the total brain volume irradiated to low doses compared with the VMAT plans. The average ratios of NTCP between PSPT and VMAT were 0.56 and 0.38 for glioma and ependymoma patients respectively and the average ratios of NTCP between IMPT and VMAT were 0.67 and 0.68 for glioma and ependymoma plans respectively. Sensitivity test revealed that predicted ratios of risk were insensitive to range and positional errors but varied with risk model selection. Conclusion: Both PSPT and IMPT plans resulted in a decrease in the predictive risk of necrosis for the pediatric plans studied in this work. Sensitivity analysis upheld the qualitative findings of the risk models used in this study, however more accurate models that take into account dose and volume are needed.

  7. Post-Irradiation Properties of Candidate Materials for High-Power Targets

    International Nuclear Information System (INIS)

    Kirk, H.G.; Ludewig, H.; Mausner, L.F.; Simos, N.; Thieberger, P.; Brookhaven; Hayato, Y.; Yoshimura, K.; McDonald, K.T.; Sheppard, J.; Trung, L.P.

    2006-01-01

    The desire of the high-energy-physics community for more intense secondary particle beams motivates the development of multi-megawatt, pulsed proton sources. The targets needed to produce these secondary particle beams must be sufficiently robust to withstand the intense pressure waves arising from the high peak-energy deposition which an intense pulsed beam will deliver. In addition, the materials used for the targets must continue to perform in a severe radiation environment. The effect of the beam-induced pressure waves can be mitigated by use of target materials with high-yield strength and/or low coefficient of thermal expansion (CTE) [1, 2, 3]. We report here first results of an expanded study of the effects of irradiation on several additional candidate materials with high strength (AlBeMet, beryllium, Ti-V6-Al4) or low CTE (a carbon-carbon composite, a new Toyota ''gum'' metal alloy [4], Super-Invar)

  8. Harmful Effects of Formaldehyde and Possible Protective Effect of ...

    African Journals Online (AJOL)

    2017-05-22

    May 22, 2017 ... the ocular and respiratory system, but it also affects the nervous and genital system. ... possible protective effect of Nigella sativa on the trachea of rats. Niger ..... Vitamin A deficiency in the tracheal epithelium of rats has been ...

  9. Post-Irradiation Examination Test of the Parts of X-Gen Nuclear Fuel Assembly

    International Nuclear Information System (INIS)

    Ahn, S. B.; Ryu, W. S.; Choo, Y. S.

    2008-08-01

    The mechanical properties of the parts of a nuclear fuel assembly are degraded during the operation of the reactor, through the mechanism of irradiation damage. The properties changes of the parts of the fuel assembly should be quantitatively estimated to ensure the safety of the fuel assembly and rod during the operation. The test techniques developed in this report are used to produce the irradiation data of the grid 1x1 cell spring, the grid 1x1 cell, the spring on one face of the 1x1 cell, the inner/outer strip of the grid and the welded part. The specimens were irradiated in the CT test hole of HANARO of a 30 MW thermal output at 300 deg. C during about 100 days From the spring test of mid grid 1x1 cell and grid plate, the irradiation effects can be examined. The irradiation effects on the irradiation growth also were occurred. The buckling load of mid grid 1x1 cell does not change with a neutron irradiation. From the tensile tests, the strengths increased but the elongations decreased due to an irradiation. The tensile test and microstructure examination of the spot and fillet welded parts are performed for the evaluation of an irradiation effects. Through these tests of components, the essential data on the fuel assembly design could be obtained. These results will be used to update the irradiation behavior databases, to improve the performance of fuel assembly, and to predict the service life of the fuel assembly in a reactor

  10. Electrical in situ and post-irradiation properties of ceramics relevant to fusion irradiation conditions

    International Nuclear Information System (INIS)

    Shikama, Tatsuo; Zinkle, S.J.

    2002-01-01

    Electrical properties of ceramic candidate materials for the next-generation nuclear fusion devices under relevant irradiation conditions are reviewed. A main focal point is placed on the degradation behavior of the electrical insulating ability during and after irradiation. Several important radiation induced effects play important roles: radiation induced conductivity, thermally stimulated electrical conductivity, radiation induced electrical charge separation, and radiation induced electromotive force. These phenomena will interact with each other under fusion relevant irradiation conditions. The design of electrical components for the next-generation fusion devices should take into account these complicated interactions among the radiation induced phenomena

  11. DAMAGE IN MOLYBDENUM ASSOCIATED WITH NEUTRON IRRADIATION AND SUBSEQUENT POST-IRRADIATION ANNEALING

    Energy Technology Data Exchange (ETDEWEB)

    Mastel, B.

    1963-07-23

    Molybdemum containing carbon was studied in an attempt to establish the combined effect of impurity content and neutron irradiation on the properties and structure of specific metals. Molybdenum foils were punched into discs and heat treated in vacuum. They were then slow-cooled and irradiated. After irradiation and subsequent decay of radioactivity to a low level the foils were subjected to x-ray diffraction measurements. Cold-worked foils with less than 10 ppm carbon showed no change in microstructure due to irradiation. Molybdenum foils that were annealed prior to irradiation showed spot defects. In foils containing up to 500 ppm carbon, it was concluded that the small loops present after irradiation are due to the clustering of point defects at interstitial carbon atoms, followed by collapse to form a dislocation loop. The amount of lattice expansion after irradiation was strongly dependent on impurity content. Neutron irradiation was found to reduce the number of active slip systems. (M.C.G.)

  12. Post-irradiation characterization of PH13-8Mo martensitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Jong, M.; Schmalz, F.; Rensman, J.W. [Nuclear Research and consultancy Group, Westerduinweg 3, 1755 ZG Petten (Netherlands); Luzginova, N.V., E-mail: luzginova@nrg.eu [Nuclear Research and consultancy Group, Westerduinweg 3, 1755 ZG Petten (Netherlands); Wouters, O.; Hegeman, J.B.J.; Laan, J.G. van der [Nuclear Research and consultancy Group, Westerduinweg 3, 1755 ZG Petten (Netherlands)

    2011-10-01

    The irradiation response of PH13-8Mo stainless steel was measured up to 2.5 dpa at 200 and 300 deg. C irradiation temperatures. The PH13-8Mo, a martensitic precipitation-hardened steel, was produced by Hot Isostatic Pressing at 1030 deg. C. The fatigue tests (high cycle fatigue and fatigue crack propagation) showed a test temperature dependency but no irradiation effects. Tensile tests showed irradiation hardening (yield stress increase) of approximately 37% for 200 deg. C irradiated material tested at 60 deg. C and approximately 32% for 300 deg. C irradiated material tested at 60 deg. C. This contradicts the shift in reference temperature (T{sub 0}) measured in toughness tests (Master Curve approach), where the {Delta}T{sub 0} for 300 deg. C irradiated is approximately 170 deg. C and the {Delta}T{sub 0} for the 200 deg. C irradiated is approximately 160 deg. C. This means that the irradiation hardening of PH13-8Mo steel is not suitable to predict the shift in the reference temperature for the Master Curve approach.

  13. Post irradiation fracture properties of precipitation-strengthened alloy D21

    International Nuclear Information System (INIS)

    Huang, F.H.

    1986-03-01

    The precipitation strengthened alloys have the potential for use in fuel cladding and duct applications for liquid metal reactors due to their high strength and low swelling rate. Unfortunately, these high strength alloys tend to exhibit poor fracture toughness, and the effects of neutron irradiation on the fracture properties of the material are of concern. Compact tension specimens of alloy D21 were irradiated in the Experimental Breeder Reactor II to a fluence of 2.7 x 10 22 n/cm 2 (E > 0.1 MeV) at 425, 500, 550 and 600 0 C. Fracture toughness tests on these specimens wre performed using electric potential techniques at temperatures ranging from 205 to 425 C. The material exhibited low postirradiation fracture toughness which increased with either increasing test or irradiation temperature. The tearing modulus, however, increased with increasing irradiation temperature but decreased with increasing test temperature. Results wre analyzed using the J-integral approach. The fracture toughness of irradiated D21 was evaluated essentially following the procedure recommended in ASTM Test Method E813. It was found that the data elimination limits illustrated in E813 were too large for the specimens tested, although the thickness criterion was satisfied. The precautions needed to determine J/sub 1c/ based on a reduced data qualification range were disussed

  14. Development of a miniaturized bulge test (small punch test) for post-irradiation mechanical property evaluation

    International Nuclear Information System (INIS)

    Eto, Motokuni; Suzuki, Masahide; Nishiyama, Yutaka; Fukaya, Kiyoshi; Jitsukawa, Shiro; Misawa, Toshihei

    1993-01-01

    To examine the effectiveness of the small punch test for evaluating strength and toughness of irradiated ferritic steels, detailed procedures are described aiming at standardization of the test. The statistical approach to analysis of the SP energy as a function of temperature for evaluation of DBTT was also reviewed. The method was then applied to neutron-irradiated ferritic steels, which included F-82, F-82H, HT-9, and 2 1/4 Cr-1Mo steel. Fluence and irradiation temperatures ranged from 2 to 12 x 10 23 n/m 2 (E ≥ 1 MeV) and from 573 to 673 K, respectively. Comparison of parameters obtained from the small punch test with the properties measured by the conventional method indicated that: (a) the 0.2% offset stress and the ultimate tensile strength at room temperature can be correlated well with the parameters, P y /(t 0 ) 2 and P max /(t 0 ) 2 , respectively. Here, P y and P max are the loads corresponding to the yield and the maximum, and t 0 is the initial thickness of a specimen; (b) fracture toughness, J IC , can be evaluated using equivalent fracture strain, anti ε qf , and the previously established relationship between these values; and (c) DBTT measured by a Charpy test can be predicted from the results of temperature dependence of SP energy determined from the area under the load-deflection curve using a statistical analysis based on a Weibull distribution

  15. The Possible Protective Role of Curcumin against Radiation Induced Cytogenetic Damages in Mice

    International Nuclear Information System (INIS)

    Hassan, M.R.M.

    2014-01-01

    This study was undertaken to investigate the effect of curcumin on radiation induced damages in albino male mice. Animals were injected intraperitoneally with 20 mg/kg body weight curcumin 30 minutes prior to whole body gamma-irradiation (4Gy). Animals were sacrificed after 1, 3 and 7 days of the irradiation. The possible radioprotective effect of curcumin on bone marrow chromosomes, DNA fragmentation, superoxide dismutase (SOD) activity, reduced glutathione (GSH) content, malondialdehyde (MDA) level, total free radicals in spleen, and peripheral blood differential count was examined at the different time intervals of the experiment. Radiation exposure resulted in a statistically significant elevation in the percentage of the aberrant metaphases, total amount of chromosomal damage, percentage of the DNA fragmentation, (MDA) level, decline in the activities of (SOD) and (GSH) contents, at 1, 3 and 7 days post-irradiation, elevation in the total free radicals one day post-irradiation and percentage of the total number of normal and abnormal white blood cells after 1, 3 days of irradiation specially the abnormal lymphocytes and neutrophils. Curcumin showed a clastogenic effect that it caused elevation of the total number of aberrant cells, structural and numerical aberrant cells after 1 and 3 days of the experiment. Moreover, curcumin caused a decline in the liver (GSH) content after 1, 3 and 7 days of the experiment. On the other hand, intraperitoneal injection of curcumin before irradiation didn‘t show any protective effect on the total aberrant cells and structural aberrant cells induced by irradiation, liver (GSH) content and the percentage of the DNA fragmentation, liver (MDA) level and number of abnormal leukocytes. In contrast, it showed potentiating effect on the numerical type aberrations especially endomitosis after one day post-irradiation. In addition, elevation in the percentage of the total free radicals induced by curcumin 3 and 7 days post-irradiation

  16. Intermittent hormonal therapy in the treatment of post-irradiation residual/recurrent prostate cancer

    International Nuclear Information System (INIS)

    Williams, Aaron O; Kocherill, Paul G; Wallace, Michelle; Forman, Jeffrey D

    1996-01-01

    time, lower cost, fewer side effects and possibly improved quality of life. Whether IHT will prolong the duration of response remains to be determined

  17. Sun protection counseling by pediatricians has little effect on parent and child sun protection behavior.

    Science.gov (United States)

    Cohen, Liza; Brown, Judith; Haukness, Heather; Walsh, Lori; Robinson, June K

    2013-02-01

    To compare counseling concerning sun protection and outdoor exercise with the parent's report of the behavior of a child aged 9-16 years old. Structured interviews of medical personnel in 3 Chicago area practices elicited information about counseling methods and recommendations. In each practice, a convenience sample of parents completed a self-reported survey of their and their child's behavior. Sun protection counseling occurred more frequently than exercise counseling in all practices (P = .014). Sun protection counseling was associated with parental prompting (P = .004), performing a summer camp physical (P = .002), and the child having a sunburn (P = .003). After controlling for the child's age, sex, and skin tone, sun protection counseling was not associated with the child's use of sun protection. In multivariate analysis of the child's sun protection behavior, parental sunburns, indoor tanning in the last 12 months, perception of skin cancer risk, and sun protection self-efficacy were significant (P = .02). Children who pursued outdoor sports were twice as likely to use inadequate sun protection and sustain sunburns (CI 1.3-1.7). The child's sun protection behavior was influenced by parental sun protection, parental perception of skin cancer risk, and parental sun protection self-efficacy; therefore, sun protection for children needs to be aimed at parents as well as children. Communication with parents in a way that incorporates the principles of motivational interviewing may be more effective in promoting behavioral change than admonitions to use sunscreen. Copyright © 2013 Mosby, Inc. All rights reserved.

  18. Neutron effects in humans: protection considerations

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1985-01-01

    Committee I of the International Commission on Radiological Protection has recommended that the Quality Factor for neutrons should be changed from 10 to 20. This article is an interesting recount of the tale of Q from the viewpoint of an observer which illustrates many of the problems that the selection of protection standards pose. 32 refs., 5 tabs

  19. Protective Effect of Phoenix dactylifera-L Extracts against Radiation-Induced Cardio-Toxicity and Some Biochemical Changes in Male Albino Rats

    International Nuclear Information System (INIS)

    Mangood, S.A.; Kamal, A.M.

    2011-01-01

    The Antioxidant properties of the date palm fruit; Phoenix dactylifera-L in mitigation of cellular injury following free radicals release by ionizing radiation has been investigated. Forty-eight male albino rats divided equally into 6 groups were used in this study. Group 1 (G.1) acted as control, G.2 received date extract orally (4 ml/ kg/ day) for 21 days, G.3 was exposed to a single dose of gamma irradiation (6 Gy), G.4 received date extract orally at an identical dose and duration to G.2 and irradiation to G.3, G.5 received the daily date extract for 7 days post irradiation and G.6 received the daily date extract for 21 days before and for 7 days after irradiation. Heart tissue was examined histologically and biochemical testing for total cholesterol (TC), triglycerides (TG), high and low density lipoprotein-cholesterol (HDL-C and LDL-C), creatine kinase (CK), creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) was performed for each rat group. Data from the investigation showed that gamma irradiation caused histopathological damage to the heart tissue and disturbances in most parameters related to cardiac function. Administration of date extracts pre-irradiation provided evidence of a potential protective effect against irradiation hazard

  20. Fabrication, irradiation and post-irradiation examinations of MO2 and UO2 sphere-pac and UO2 pellet fuel pins irradiated in a PWR loop

    International Nuclear Information System (INIS)

    Linde, A. van der; Lucas Luijckx, H.J.B.; Verheugen, J.H.N.

    1982-01-01

    The document reports in detail the fuel pin fabrication data and describes the irradiation conditions and history. All the relevant results of the non-destructive and destructive post-irradiation examinations are reported. They include: visual inspection and chemical analysis of crud; length and diameter measurements; neutron radiography and gamma scanning; juncture tests and fission gas analysis (including residual gas in fuel samples); microscopy and alpha + beta/gamma autoradiography; microprobe investigations; burn-up and isotopic analysis; and hydrogen analysis in clad. The data and observations obtained are discussed in detail and conclusions are given. The irradiation and post-irradiation examinations of the R-109 pins have shown the safe, pre-calculable performance of LWR fuel pins containing mixed-oxide sphere-pac fuel with the fissile material mainly present in the large spheres

  1. Radio-protective effect of sodium meclofenamate. A prospective clinical trial

    International Nuclear Information System (INIS)

    Mahafzah, M.; Halpern, J.; Nava, H.R.; Huben, R.P.; Sayyid, S.; Bryson, W.; Ambrus, J.L.

    1989-01-01

    Twentyfour patients treated with irradiation to either their pelvis or their chest for neoplastic disease were included in a randomized study of radioprotection with sodium meclofenamate (Meclomen) (SM). Seventeen patients received SM 100 mg, p.os, t.i.d., and seven received placebo. The long-range radiation related chronic gastrointestinal and urinary tract toxicity was diminished by SM. At 12 months post irradiation, SM treated patients experienced less gastrointestinal and urinary symptoms, as well as less measured bladder contraction, than the controls. Acute gastrointestinal signs of radiotoxicity, however, seemed to have been enhanced by SM. The treated patients suffered from nausea, vomiting, and diarrhea. These acute toxic effects were temporary and reversible

  2. Post-irradiation lumbosacral radiculopathy associated with multiple cavernous malformations of the cauda equina: Case report and review of the literature

    OpenAIRE

    Drazin, Doniel; Kappel, Ari; Withrow, Stefan; Perry, Tiffany; Chu, Ray; Phuphanich, Surasak

    2017-01-01

    Background: Multiple radiation-induced cavernous malformations of the cauda equina are extremely rare. A review of the literature suggested that the post-irradiation lumbosacral radiculopathy in our patient was most likely associated with a diagnosis of multiple radiation-induced cavernous malformations of the cauda equina. Case Description: A 76-year-old man with a remote history of abdominal radiation therapy presented with a 6-month history of progressively worsening right foot drop and...

  3. Experimental and inspection facilities in post-irradiation of spent fuel pools for the analysis of the behaviour of nuclear fuels in power reactors

    International Nuclear Information System (INIS)

    Ruggirello, G.; Zawerucha, A.

    1992-01-01

    Since the beginning of the Atomic Nuclear Reactors (PHWR) Atucha I and Embalse in Argentine are employed different techniques for the knowing of the fuel bundles performances. It is detailed the facilities on post-irradiation examination. The techniques described are: online measurements, visual inspections, identifications of defective fuels and rods assemblies in spent fuel pools. This controls have made possible the feed-back to the manufactory process and the changes in the manufactory quality controls. (author)

  4. First results of the post-irradiation examination of the Ceramic Breeder materials from the Pebble Bed Assemblies Irradiation for the HCPB Blanket concept

    International Nuclear Information System (INIS)

    Hegeman, J.; Magielsen, A.J.; Peeters, M.; Stijkel, M.P.; Fokkens, J.H.; Laan, J.G. van der

    2006-01-01

    In the framework of developing the European Helium Cooled Pebble-Bed (HCPB) blanket an irradiation test of pebble-bed assemblies is performed in the HFR Petten. The experiment is focused on the thermo-mechanical behavior of the HCPB type breeder pebble-bed at DEMO representative levels of temperature and defined thermal-mechanical loads. To achieve representative conditions a section of the HCPB is simulated by EUROFER-97 cylinders with a horizontal bed of ceramic breeder pebbles sandwiched between two beryllium beds. Floating Eurofer-97 steel plates separate the pebble-beds. The structural integrity of the ceramic breeder materials is an issue for the design of the Helium Cooled Pebble Bed concept. Therefore the objective of the post irradiation examination is to study deformation of pebbles and the pebble beds and to investigate the microstructure of the ceramic pebbles from the Pebble Bed Assemblies. This paper concentrates on the Post Irradiation Examination (PIE) of the four ceramic pebble beds that have been irradiated in the Pebble Bed Assembly experiment for the HCPB blanket concept. Two assemblies with Li 4 SiO 4 pebble-beds are operated at different maximum temperatures of approximately 600 o C and 800 o C. Post irradiation computational analysis has shown that both have different creep deformation. Two other assemblies have been loaded with a ceramic breeder bed of two types of Li 2 TiO 3 beds having different sintering temperatures and consequently different creep behavior. The irradiation maximum temperature of the Li 2 TiO 3 was 800 o C. To support the first PIE result, the post irradiation thermal analysis will be discussed because thermal gradients have influence on the pebble-bed thermo-mechanical behavior and as a result it may have impact on the structural integrity of the ceramic breeder materials. (author)

  5. Post irradiation examination of type 316 stainless steels for in-pile Oarai water loop No.2 (OWL-2)

    International Nuclear Information System (INIS)

    Shibata, Akira; Kimura, Tadashi; Nagata, Hiroshi; Aoyama, Masashi; Kanno, Masaru; Ohmi, Masao

    2010-11-01

    The Oarai water loop No.2 (OWL-2) was installed in JMTR in 1972 for the purpose of irradiation experiments of fuel element and component material for light water reactors. Type 316 stainless steels (SSs) were used for tube material of OWL-2 in the reactor. But data of mechanical properties of highly irradiated Type 316 SSs has been insufficient since OWL-2 was installed. Therefore surveillance tests of type 316 SSs which were irradiated up to 3.4x10 25 n/m 2 in fast neutron fluence (>1 MeV) were performed. Meanwhile type 316 stainless steel (SS) is widely used in JMTR such as other irradiation apparatus and irradiation capsule, and additional data of type 316 SSs irradiated higher is required. Therefore post irradiation examinations of surveillance specimens made of type 316 SSs which were irradiated up to 1.0x10 26 n/m 2 in fast neutron fluence were performed and reported in this paper. In this result of surveillance tests of type 316 SSs irradiated up to 1.0x10 26 n/m 2 , tensile strength increase with increase of Neutron fluence and total elongation decreased with increase of Neutron fluence compared to unirradiated specimens and specimens irradiated up to 3.4x10 25 n/m 2 . This tendency has good agreement with results of 10 24 - 10 25 n/m 2 in fast neutron fluence. More than 37% in total elongation was confirmed in all test conditions. It was confirmed that type 316 SS irradiated up to 1.0x10 26 n/m 2 in fast neutron fluence has enough ductility as structure material. (author)

  6. Improving thermal model prediction through statistical analysis of irradiation and post-irradiation data from AGR experiments

    International Nuclear Information System (INIS)

    Pham, Binh T.; Hawkes, Grant L.; Einerson, Jeffrey J.

    2014-01-01

    As part of the High Temperature Reactors (HTR) R and D program, a series of irradiation tests, designated as Advanced Gas-cooled Reactor (AGR), have been defined to support development and qualification of fuel design, fabrication process, and fuel performance under normal operation and accident conditions. The AGR tests employ fuel compacts placed in a graphite cylinder shrouded by a steel capsule and instrumented with thermocouples (TC) embedded in graphite blocks enabling temperature control. While not possible to obtain by direct measurements in the tests, crucial fuel conditions (e.g., temperature, neutron fast fluence, and burnup) are calculated using core physics and thermal modeling codes. This paper is focused on AGR test fuel temperature predicted by the ABAQUS code's finite element-based thermal models. The work follows up on a previous study, in which several statistical analysis methods were adapted, implemented in the NGNP Data Management and Analysis System (NDMAS), and applied for qualification of AGR-1 thermocouple data. Abnormal trends in measured data revealed by the statistical analysis are traced to either measuring instrument deterioration or physical mechanisms in capsules that may have shifted the system thermal response. The main thrust of this work is to exploit the variety of data obtained in irradiation and post-irradiation examination (PIE) for assessment of modeling assumptions. As an example, the uneven reduction of the control gas gap in Capsule 5 found in the capsule metrology measurements in PIE helps identify mechanisms other than TC drift causing the decrease in TC readings. This suggests a more physics-based modification of the thermal model that leads to a better fit with experimental data, thus reducing model uncertainty and increasing confidence in the calculated fuel temperatures of the AGR-1 test

  7. Improving thermal model prediction through statistical analysis of irradiation and post-irradiation data from AGR experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Binh T., E-mail: Binh.Pham@inl.gov [Human Factor, Controls and Statistics Department, Nuclear Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Hawkes, Grant L. [Thermal Science and Safety Analysis Department, Nuclear Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Einerson, Jeffrey J. [Human Factor, Controls and Statistics Department, Nuclear Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415 (United States)

    2014-05-01

    As part of the High Temperature Reactors (HTR) R and D program, a series of irradiation tests, designated as Advanced Gas-cooled Reactor (AGR), have been defined to support development and qualification of fuel design, fabrication process, and fuel performance under normal operation and accident conditions. The AGR tests employ fuel compacts placed in a graphite cylinder shrouded by a steel capsule and instrumented with thermocouples (TC) embedded in graphite blocks enabling temperature control. While not possible to obtain by direct measurements in the tests, crucial fuel conditions (e.g., temperature, neutron fast fluence, and burnup) are calculated using core physics and thermal modeling codes. This paper is focused on AGR test fuel temperature predicted by the ABAQUS code's finite element-based thermal models. The work follows up on a previous study, in which several statistical analysis methods were adapted, implemented in the NGNP Data Management and Analysis System (NDMAS), and applied for qualification of AGR-1 thermocouple data. Abnormal trends in measured data revealed by the statistical analysis are traced to either measuring instrument deterioration or physical mechanisms in capsules that may have shifted the system thermal response. The main thrust of this work is to exploit the variety of data obtained in irradiation and post-irradiation examination (PIE) for assessment of modeling assumptions. As an example, the uneven reduction of the control gas gap in Capsule 5 found in the capsule metrology measurements in PIE helps identify mechanisms other than TC drift causing the decrease in TC readings. This suggests a more physics-based modification of the thermal model that leads to a better fit with experimental data, thus reducing model uncertainty and increasing confidence in the calculated fuel temperatures of the AGR-1 test.

  8. Analysis on the post-irradiation examination of the HANARO miniplate-1 irradiation test for Kijang research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Man; Tahk, Young Wook; Jeong, Yong Jin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); and others

    2017-08-15

    The construction project of the Kijang research reactor (KJRR), which is the second research reactor in Korea, has been launched. The KJRR was designed to use, for the first time, U–Mo fuel. Plate-type U–7 wt.% Mo/Al–5 wt.% Si, referred to as U–7Mo/Al–5Si, dispersion fuel with a uranium loading of 8.0 gU/cm{sup 3}, was selected to achieve higher fuel efficiency and performance than are possible when using U{sub 3}Si{sub 2}/Al dispersion fuel. To qualify the U–Mo fuel in terms of plate geometry, the first miniplates [HANARO Miniplate (HAMP-1)], containing U–7Mo/Al–5Si dispersion fuel (8 gU/cm{sup 3}), were fabricated at the Korea Atomic Energy Research Institute and recently irradiated at HANARO. The PIE (Post-irradiation Examination) results of the HAMP-1 irradiation test were analyzed in depth in order to verify the safe in-pile performance of the U–7Mo/Al–5Si dispersion fuel under the KJRR irradiation conditions. Nondestructive analyses included visual inspection, gamma spectrometric mapping, and two-dimensional measurements of the plate thickness and oxide thickness. Destructive PIE work was also carried out, focusing on characterization of the microstructural behavior using optical microscopy and scanning electron microscopy. Electron probe microanalysis was also used to measure the elemental concentrations in the interaction layer formed between the U–Mo kernels and the matrix. A blistering threshold test and a bending test were performed on the irradiated HAMP-1 miniplates that were saved from the destructive tests. Swelling evaluation of the U–Mo fuel was also conducted using two methods: plate thickness measurement and meat thickness measurement.

  9. Analysis on the post-irradiation examination of the HANARO miniplate-1 irradiation test for kijang research reactor

    Directory of Open Access Journals (Sweden)

    Jong Man Park

    2017-08-01

    Full Text Available The construction project of the Kijang research reactor (KJRR, which is the second research reactor in Korea, has been launched. The KJRR was designed to use, for the first time, U–Mo fuel. Plate-type U–7 wt.% Mo/Al–5 wt.% Si, referred to as U–7Mo/Al–5Si, dispersion fuel with a uranium loading of 8.0 gU/cm3, was selected to achieve higher fuel efficiency and performance than are possible when using U3Si2/Al dispersion fuel. To qualify the U–Mo fuel in terms of plate geometry, the first miniplates [HANARO Miniplate (HAMP-1], containing U–7Mo/Al–5Si dispersion fuel (8 gU/cm3, were fabricated at the Korea Atomic Energy Research Institute and recently irradiated at HANARO. The PIE (Post-irradiation Examination results of the HAMP-1 irradiation test were analyzed in depth in order to verify the safe in-pile performance of the U–7Mo/Al–5Si dispersion fuel under the KJRR irradiation conditions. Nondestructive analyses included visual inspection, gamma spectrometric mapping, and two-dimensional measurements of the plate thickness and oxide thickness. Destructive PIE work was also carried out, focusing on characterization of the microstructural behavior using optical microscopy and scanning electron microscopy. Electron probe microanalysis was also used to measure the elemental concentrations in the interaction layer formed between the U–Mo kernels and the matrix. A blistering threshold test and a bending test were performed on the irradiated HAMP-1 miniplates that were saved from the destructive tests. Swelling evaluation of the U–Mo fuel was also conducted using two methods: plate thickness measurement and meat thickness measurement.

  10. Post irradiation conical keratosis

    International Nuclear Information System (INIS)

    Vestey, J.P.; Hunter, J.A.A.; Mallet, R.B.; Rodger, A.

    1989-01-01

    The authors have recently seen 3 patients affected by a widespread eruption of minute keratoses confined to areas of irradiated skin with clinical and histologial features of which they have been unable to find previous literary descriptions. A fourth patient with similar clinical and histopathological features occurring after exposure only to actinic irradiation is described. (author)

  11. Post irradiation conical keratosis

    Energy Technology Data Exchange (ETDEWEB)

    Vestey, J.P.; Hunter, J.A.A. (Royal Infirmary, Edinburgh (UK)); Mallet, R.B. (Westminster Hospital, London (UK)); Rodger, A. (Western General Hospital, Edinburgh (UK))

    1989-03-01

    The authors have recently seen 3 patients affected by a widespread eruption of minute keratoses confined to areas of irradiated skin with clinical and histologial features of which they have been unable to find previous literary descriptions. A fourth patient with similar clinical and histopathological features occurring after exposure only to actinic irradiation is described. (author).

  12. Post-irradiation DNA synthesis inhibition and G2 phase delay in radiosensitive body cells from non-Hodgkin's lymphoma patients: An indication of cell cycle defects

    International Nuclear Information System (INIS)

    Hannan, Mohammed A.; Kunhi, Mohammed; Einspenner, Michael; Khan, Bashir A.; Al-Sedairy, Sultan

    1994-01-01

    In the present study, both post-irradiation DNA synthesis and G 2 phase accumulation were analyzed in lymphoblastoid cell lines (LCLs) and fibroblast cell strains derived from (Saudi) patients with non-Hodgkin's lymphoma (NHL), ataxia telangiectasia (AT), AT heterozygotes and normal subjects. A comparison of the percent DNA synthesis inhibition (assayed by 3 H-thymidine uptake 30 min after irradiation), and a 24 h post-irradiation G 2 phase accumulation determined by flow cytometry placed the AT heterozygotes and the NHL patients in an intermediate position between the normal subjects (with maximum DNA synthesis inhibition and minimum G 2 phase accumulation) and the AT homozygotes (with minimum DNA synthesis inhibition and maximum G 2 accumulation). The similarity between AT heterozygotes and the NHL patients with respect to the two parameters studied after irradiation was statistically significant. The data indicating a moderate abnormality in the control of cell cycle progression after irradiation in the LCLs and fibroblasts from NHL patients may explain the enhanced cellular and chromosomal radiosensitivity in these patients reported by us earlier. In addition to demonstrating a link between cell cycle abnormality and radiosensitivity as a possible basis for cancer susceptibility, particularly in the NHL patients, the present studies emphasized the usefulness of the assay for 24 h post-irradiation G 2 phase accumulation developed elsewhere in characterizing AT heterozygote-like cell cycle anomaly in cancer patients irrespective of whether they carried the AT gene or any other affecting the cell cycle

  13. Radiation biology and radiation protection

    International Nuclear Information System (INIS)

    Hendry, J.H.

    2012-01-01

    For protection purposes, the biological effects of radiation are separated into stochastic effects (cancer, hereditary effects) presumed to be unicellular in origin, and tissue reactions due to injury in populations of cells. The latter are deterministic effects, renamed ‘tissue reactions’ in the 2007 Recommendations of the International Commission on Radiological Protection because of the increasing evidence of the ability to modify responses after irradiation. Tissue reactions become manifest either early or late after doses above a threshold dose, which is the basis for recommended dose limits for avoiding such effects. Latency time before manifestation is related to cell turnover rates, and tissue proliferative and structural organisation. Threshold doses have been defined for practical purposes at 1% incidence of an effect. In general, threshold doses are lower for longer follow-up times because of the slow progression of injury before manifestation. Radiosensitive individuals in the population may contribute to low threshold doses, and in the future, threshold doses may be increased by the use of various biological response modifiers post irradiation for reducing injury. Threshold doses would be expected to be higher for fractionated or protracted doses, unless doses below the threshold dose only cause single-hit-type events that are not modified by repair/recovery phenomena, or if different mechanisms of injury are involved at low and high doses.

  14. Effective construction of environmental protection agreements

    International Nuclear Information System (INIS)

    French, H.F.

    1995-01-01

    By now 170 international agreements are designed to protect air, ground, water and organisms from man-made hazards. Nevertheless are innovative approaches required for global conventions to make the Earth a sanctuary of life for good. (orig.) [de

  15. Measuring the effectiveness of protected area networks in reducing deforestation.

    Science.gov (United States)

    Andam, Kwaw S; Ferraro, Paul J; Pfaff, Alexander; Sanchez-Azofeifa, G Arturo; Robalino, Juan A

    2008-10-21

    Global efforts to reduce tropical deforestation rely heavily on the establishment of protected areas. Measuring the effectiveness of these areas is difficult because the amount of deforestation that would have occurred in the absence of legal protection cannot be directly observed. Conventional methods of evaluating the effectiveness of protected areas can be biased because protection is not randomly assigned and because protection can induce deforestation spillovers (displacement) to neighboring forests. We demonstrate that estimates of effectiveness can be substantially improved by controlling for biases along dimensions that are observable, measuring spatial spillovers, and testing the sensitivity of estimates to potential hidden biases. We apply matching methods to evaluate the impact on deforestation of Costa Rica's renowned protected-area system between 1960 and 1997. We find that protection reduced deforestation: approximately 10% of the protected forests would have been deforested had they not been protected. Conventional approaches to evaluating conservation impact, which fail to control for observable covariates correlated with both protection and deforestation, substantially overestimate avoided deforestation (by over 65%, based on our estimates). We also find that deforestation spillovers from protected to unprotected forests are negligible. Our conclusions are robust to potential hidden bias, as well as to changes in modeling assumptions. Our results show that, with appropriate empirical methods, conservation scientists and policy makers can better understand the relationships between human and natural systems and can use this to guide their attempts to protect critical ecosystem services.

  16. Experimental and theoretical studies on radiation protective effect of a lighter non-lead protective apron

    International Nuclear Information System (INIS)

    Takano, Yoshihisa; Ono, Koji; Okazaki, Keiichiro

    2005-01-01

    Non-lead aprons using composite materials are often used for radiation protective aprons instead of heavy lead aprons. However, the protective effect of the lighter, non-lead aprons has not been well evaluated, and it is not yet clear how they compare with lead aprons. Therefore, we investigated the protective performance of non-lead aprons theoretically and experimentally by comparing them with lead aprons under clinical conditions. We measured the energy spectra for direct and scattered-rays passing through protective aprons or not, and measured doses with glass dosimeters for validation of theoretical calculations based on the energy spectra. We found that the protective effect of non-lead aprons was higher than that of lead aprons at X-ray of tube voltages of 70-100 kV, which are often used for radiography and fluorography. This demonstrated that the non-lead aprons are more useful in many situations than heavy lead aprons. (author)

  17. The effect of non-steroid antiphlogistics on the course of acute radiation sickness

    International Nuclear Information System (INIS)

    Juchelkova, L.; Hofer, M.; Pospisil, M.

    1998-01-01

    A number of new non-steroid antiphlogistics have been synthesized recently with a view to reducing their side effects on the gastrointestinal tract. Among them is a derivative of one of conventional antiphlogistics, flurbiprofen 4-nitroxybutyl ester, from which nitrogen oxide (NO) is released in the gastrointestinal tract. NO has a protective effect on the mucous membrane. Experiments gave evidence that this modification of the flurbiprofen molecule does not bring about reduction of the stimulating effect on the post-irradiation recovery of blood formation. Owing to its low toxicity towards the gastrointestinal tract, flurbiprofen 4-nitroxybutyl ester appears to be a promising drug for protection against radiation-induced myelosuppression

  18. The post irradiation examination of fuel in support of Bruce A nuclear division fueling with flow program

    International Nuclear Information System (INIS)

    Montin, J.; Sagat, S.; Day, R.; Novak, J.; Bromfield, H.

    1995-01-01

    Bruce A Nuclear Division (BAND) units are operating at ∼ 75% of full power, because of the potential of a power pulse in the event of an inlet header break. As a result, BAND is converting to fueling with flow, to eliminate the potential of a power pulse and to allow for full-power operation. Concerns regarding the integrity of the end-of-life (EOL) bundles interacting with the latch at the downstream end of the fuel channel were raised. BAND carried out a test program in which EOL bundles in the upstream position 13 of Unit 2 were cascaded into the downstream latch position 1 of another channel. Six of twelve cascaded bundles and two typical EOL position 13 (benchmark) bundles were selected for post-irradiation examination (PIE). Incipient cracks were found in the assembly welds (endplateto-endcap welds) of all six cascaded bundles. No incipient cracks were found in the benchmark bundles. Metallographic and fractographic examination, along with crack dating, and hydrogen and deuterium analyses, indicated that the incipient cracks were the result of delayed-hydride assisted cracking at the EOL. Consequently, Ontario Hydro changed the design of the outlet shield plug to support all three rings of the fuel bundle, to minimize stress and prevent endplate cracking. Also, an ultrasonic endplate inspection tool (UT) was developed and located in the fuel bay. to inspect fuelbundle endplates for cracks. A second test was done involving a series of four bundle cascades in BAND Unit 4 channels that had new outlet shield plugs. The latch bundles were discharged after a hot shutdown. The cascaded Unit 2 and Unit 4 latch bundles were checked for cracks using the UT. The PIE found incipient cracks or less-than-ideal welds in the assembly welds of fuel elements from Unit 2 (latch-supported fuel bundles) that had been identified by the UT as having incipient cracks. No incipient cracks were found in the assembly welds of fuel elements from Unit 4 (new outlet shield

  19. The post-irradiation examination of fuel in support of Bruce A Nuclear Division fueling with flow program

    International Nuclear Information System (INIS)

    Montin, J.; Sagat, S.

    1995-10-01

    Bruce A Nuclear Division (BAND) units are operating at ∼ 75% of full power, because of the potential of a power pulse in the event of an inlet header break. As a result, BAND is converting to fueling with flow, to eliminate the potential of a power pulse and to allow for full-power operation. Concerns regarding the integrity of the end-of-life (EOL) bundles interacting with the latch at the downstream end of the fuel channel were raised. BAND carried out a test program in which EOL bundles in the upstream position of 13 of Unit 2 were cascaded into the downstream latch position 1 of another channel. Six of twelve cascaded bundles and two typical EOL position 13 (benchmark) bundles were selected for post-irradiation examination (PIE). Incipient cracks were found in the benchmark bundles. Metallographic and fractographic examination, along with crack dating, and hydrogen and deuterium analyses, indicated that the incipient cracks were the result of delayed-hydride assisted cracking at the EOL. Consequently, Ontario Hydro changed the design of the outlet shield plug to support all three rings of the fuel bundle, to minimize stress and prevent end plate cracking. Also, an ultrasonic end plate inspection tool (UT) was developed and located in the fuel bay, to inspect fuel-bundle end plates for cracks. A second test was done involving a series of four bundle cascades in BAND Unit 4 channels that had new outlet shield plugs. The latch bundles were discharged after a hot shutdown. The cascaded Unite 2 and Unit 4 latch bundles were checked for cracks using the UT. The PIE found incipient cracks or less-than-ideal welds in the assembly welds of fuel elements from Unit 2 (latch-supported fuel bundles) that had been identified by the UT as having incipient cracks. No incipient cracks were found in the assemble welds of fuel elements from Unit 4 (new outlet shield-supported fuel bundles) confirming the UT results. (author). 5 refs., 8 figs

  20. Protective effect of edaravone against tobramycin-induced ototoxicity

    NARCIS (Netherlands)

    Asplund, Monika Stenkvist; Lidian, Adnan; Linder, Birgitta; Takumida, Masaya; Anniko, Matti

    2009-01-01

    Conclusion. It is suggested that simultaneous treatment with the radical scavenger edaravone has an effective protective effect against tobramycin ototoxicity in rat. Even if the edaravone treatment is postponed for 7 days, it can still prevent hearing loss, but a 14 day delay cannot protect from

  1. Early Post-Irradiation Changes in the Metabolism of Biogenic Amines; Les Changements Precoces du Metabolisme des Amines Biogenes apres Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Deanovic, Z [Institut Rudjer Boskovic, Zagreb, Yugoslavia (Croatia)

    1971-03-15

    There is accumulating evidence for the radiation-induced release of biogenic amines from their body stores. Having in mind the high patho-physiological activity of these ''local'' hormones and ''neuro-hormones'', it is reasonable to assume that they play an important role in the pathogenesis of the acute radiation syndrome. Under these pathological conditions the possible synergic and antagonistic effects of biogenic amines due to their complex interactions must be taken into consideration. The extent and dose-dependence of post-irradiation changes in the metabolism of histamine, serotonin, catecholamines and acetylcholine will be examined regarding particularly the search for biochemical indicators of radiation injury. The determination of bio-amines and their metabolites in urine seems to be a suitable method for following up those metabolic changes which could be of a biodosimetrical and/or prognostical value. Data published on this subject, obtained in experimental animals as well as in man, have been reviewed and the applicability of these tests is discussed. (author) [French] Des preuves se sont accumulees, qui demontrent que les amines biogenes sont liberees de leurs depots sous l'effet des rayonnements ionisants. Etant donne la grande activite pathophysiologique de ces hormones 'locales' et 'neurohormones', il est raisonnable de considerer que ces substances biogenes jouent un role important dans la pathogenese du syndrome aigu d'irradiation. Dans ces conditions pathologiques il faut tenir compte des effets synergiques et antagonistes des bio-amines, lies a des interactions compliquees. Les changements metaboliques en fonction de la dose recue font l'objet d'un examen qui englobe les alterations quantitatives de .'histamine, de la serotonine, des catecholamines et de l'acetylcholine et dont l'objectif est la recherche sur des indicateurs biochimiques de la lesion provoquee par l'irradiation. L'analyse des bio-amines et de leurs metabolites dans les urines

  2. Methodology For Evaluation Of Regulatory Effectiveness In Physical Protection

    International Nuclear Information System (INIS)

    Izmaylov, Alexander; Valente, John; Griggs, James R.; Rexroth, Paul; Piskarev, Alexander; Babkin, Vladimir; Sokolov, Egor; Melton, Ronald B.; Cunningham, Mitchel E.; Baker, Kathryn A.; Brothers, Alan J.

    2005-01-01

    Material protection, control, and accounting (MPC and A) regulatory documents play an important role in securing and protecting nuclear material by regulating a variety of activities at different hierarchical levels. The development, implementation, and practical application of these regulatory documents requires a significant investment of financial and material resources. Therefore, it is important to evaluate the effectiveness of the regulatory development process and the extent to which regulations improve the effectiveness of MPC and A at nuclear sites. The joint Russian and U.S. Regulatory Development Project has a goal of evaluating the effectiveness of regulatory documents developed for MPC and A. As part of this joint Project, a methodology for evaluating effectiveness has been developed. This methodology was developed around physical protection objectives. The developed methodology specifies physical protection objectives to be accomplished through the implementation of a regulatory system based on the physical protection goals at the nuclear sites. It includes approaches to assessing regulatory effectiveness, the hierarchical structure of physical protection objectives to be accomplished through implementing regulations, a 'mapping' of the physical protection objectives to the regulatory framework, a list of criteria for evaluating the effectiveness of physical protection regulations and effectiveness indicators, as well as means and methods for gathering information and implementation of this evaluation.

  3. Can selection explain the protective effects of farming on asthma?

    Directory of Open Access Journals (Sweden)

    Wijnand Eduard

    2015-09-01

    No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  4. Protective effects of flavonoids from corn silk on oxidative stress ...

    African Journals Online (AJOL)

    Protective effects of flavonoids from corn silk on oxidative stress induced by ... The present study aims at exploring the effects of flavonoids from corn silk (FCS) on oxidative stress induced by exhaustive exercise in mice. ... from 32 Countries:.

  5. Protective effect of building against nuclear fallout

    International Nuclear Information System (INIS)

    Mueck, K.; Lovranich, E.; Steger, F.

    1995-02-01

    In order to adopt appropriate countermeasures to protect the public in case of a wide-spread contamination after a severe reactor accident, a profound knowledge of the dose to be expected and of the dose reduction to be expected if a specific countermeasure is adopted is required. Since external radiation contributes a major fraction of up to 80 % to the total dose, the interest is focused on the reduction of external dose by staying indoors. For this purpose measurements of the dose reduction by external radiation were performed in 40 residential rooms in Vienna which were chosen according to their fraction of the Viennese building structure. They were performed by measurement of the reduction of the gamma-flux in the interior of buildings compared to the gamma-flux outside. Measurements were carried out by a HPGe-detector which was positioned 1 m above ground. The observed dose reduction factors amounted to 0.013 on the average (protection factor 78.7 ± 49.7), with the protection factors of the investigated building types ranging from 6.5 (single house in garden) to 122.9 (edicifices of the turn of the century). The observed protection factors do not include the dose reduction by dense arrangement of buildings in urban areas which has to be considered separately. The dose reduction due to different radionuclide mixtures after severe reactor accidents was also investigated. Factors similar to that observed for Cs-137 were found. The maximum deviations amounted only 12 % and therefore may be neglected in the consideration of protective measures. Additional measurements were performed with the same detector shielded by lead on all sides to determine the contribution of the interior contamination. A contribution of between < 10 % to 50 % to the external dose in the interior of buildings was observed. Measures to reduce the inner contamination in rooms (closing of windows and doors, cleaning upon entering the building interior) in case of an event are therefore

  6. Estimation of dependence between mean of fractionation of photons and neutrons dose and intensity of post-irradiation reaction of mouse large intestine

    International Nuclear Information System (INIS)

    Gasinska, A.

    1995-01-01

    The aim of the work was verification of mouse large intestine tolerance on fractionated 250 kV X-rays and 2.3 MeV neutrons doses. Two cm of large intestine of mouse CBA/HT strain were irradiated with various fraction doses: from 0.25 to 35 Gy of X-rays and 0.05-12 Gy of neutrons. The measure of injury was handicap of intestine function. Early post-irradiation reaction was measured by loss of body weight (2-3 weeks after irradiation) and mouse mortality (till 2 months after irradiation, LD50/2). The late reaction was measured on the base of maximal body weight in 1 year period after irradiation, deformation of excrements (after 10 months) and death of animals (till 12. month after irradiation, LD50/12). Fractionation of X-ray dose influenced on decrease of intensification of late irradiation effects. After fractionation of neutrons this effect has not been observed. α/β coefficient for X-rays was 19.9 Gy [15.2; 27.0] for body weight nadir, 13.4 Gy [9.3; 19.5] for early mortality (LD50/2), 6.4 Gy [3.6;11.0] for maximal body weight and 6.9 [4.2; 10.8] for late mortality (LD50/12). Analysis of influence of low doses of photons 90.25-4 Gy) and neutrons (0.05-0.8 Gy) showed trend to reduction α/β for photons only (LD50/2=5.4 Gy; LD50/12=4.6 Gy). α/β coefficient for neutrons was defined by LQ model only for maximal body weight and was 19.9 Gy [9.5; 61.0]. In application of graphic method α/β for neutrons was 230 Gy for early and 48 Gy for late effects. Lower values of α/β coefficient for late irradiation effects for photon radiation demonstrate the big influence of fractionation of photons dose on large intestine tolerance (decrease intensity in all biological effects). Author did not observe increase of intestine tolerance in fractionation of neutrons dose. Effect of irradiation damages repair in interfraction pauses, measured by percent of regenerated dose (F r ) was much bigger for photons. For X-rays it was 50% for early and 63% for late effects. In case of

  7. Evaluating heterogeneous conservation effects of forest protection in Indonesia.

    Directory of Open Access Journals (Sweden)

    Payal Shah

    Full Text Available Establishing legal protection for forest areas is the most common policy used to limit forest loss. This article evaluates the effectiveness of seven Indonesian forest protected areas introduced between 1999 and 2012. Specifically, we explore how the effectiveness of these parks varies over space. Protected areas have mixed success in preserving forest, and it is important for conservationists to understand where they work and where they do not. Observed differences in the estimated treatment effect of protection may be driven by several factors. Indonesia is particularly diverse, with the landscape, forest and forest threats varying greatly from region to region, and this diversity may drive differences in the effectiveness of protected areas in conserving forest. However, the observed variation may also be spurious and arise from differing degrees of bias in the estimated treatment effect over space. In this paper, we use a difference-in-differences approach comparing treated observations and matched controls to estimate the effect of each protected area. We then distinguish the true variation in protected area effectiveness from spurious variation driven by several sources of estimation bias. Based on our most flexible method that allows the data generating process to vary across space, we find that the national average effect of protection preserves an additional 1.1% of forest cover; however the effect of individual parks range from a decrease of 3.4% to an increase of 5.3% and the effect of most parks differ from the national average. Potential biases may affect estimates in two parks, but results consistently show Sebangau National Park is more effective while two parks are substantially less able to protect forest cover than the national average.

  8. Effect of curcumin and curcumin copper complex (1:1) on radiation-induced changes of anti-oxidant enzymes levels in the livers of Swiss albino mice

    Energy Technology Data Exchange (ETDEWEB)

    Koiram, P R; Veerapur, V P; Mazhuvancherry, U K [Manipal Coll. of Pharmaceutical Sciences, Manipal (India); Kunwar, A; Mishra, B; Barik, A; Priyadarsini, I K [Bhabha Atomic Research Center, Mumbai (India)

    2007-05-15

    The effect of mononuclear copper (II) complex of curcumin in 1:1 stoichiometry (hereafter referred to as complex) administered 30 mim before {gamma}-irradiation (4.5 Gy) on alterations in antioxidant and Thiobarbituric acid reactive substances (TBARS) levels in livers was studied in comparison to curcumin at a dose of 50 mg/kg. The different antioxidants like glutathione (GSH), glutathione-S-transferase (GST), catalase, superoxide dismuatase (SOD), TBARS and total thiols were estimated in the liver homogenates excised at different time intervals (1, 2 and 4 h) post irradiation using colorimetric methods. There was a radiation-induced decrease in the levels of all the studied enzymes at 1 h post irradiation, while an increase was observed at later time points. Both curcumin and complex treatment in sham-irradiated mice decreased the levels of GSH and total thiols, whereas there was an increase in the levels of catalase, GST and SOD compared to normal control. Under the influence of irradiation, both curcumin and complex treatment protected the decline in the levels of GSH, GST, SOD, catalase and total thiols, and inhibited radiation-induced lipid peroxidation. Further, the complex was found to be more effective in protecting the enzymes at 1 h post irradiation compared to curcumin treated group. This may be due to the higher rate constants of the complex compared to curcumin for their reactions with various free radicals. (author)

  9. Effect of curcumin and curcumin copper complex (1:1) on radiation-induced changes of anti-oxidant enzymes levels in the livers of Swiss albino mice

    International Nuclear Information System (INIS)

    Koiram, P.R.; Veerapur, V.P.; Mazhuvancherry, U.K.; Kunwar, A.; Mishra, B.; Barik, A.; Priyadarsini, I.K.

    2007-01-01

    The effect of mononuclear copper (II) complex of curcumin in 1:1 stoichiometry (hereafter referred to as complex) administered 30 mim before γ-irradiation (4.5 Gy) on alterations in antioxidant and Thiobarbituric acid reactive substances (TBARS) levels in livers was studied in comparison to curcumin at a dose of 50 mg/kg. The different antioxidants like glutathione (GSH), glutathione-S-transferase (GST), catalase, superoxide dismuatase (SOD), TBARS and total thiols were estimated in the liver homogenates excised at different time intervals (1, 2 and 4 h) post irradiation using colorimetric methods. There was a radiation-induced decrease in the levels of all the studied enzymes at 1 h post irradiation, while an increase was observed at later time points. Both curcumin and complex treatment in sham-irradiated mice decreased the levels of GSH and total thiols, whereas there was an increase in the levels of catalase, GST and SOD compared to normal control. Under the influence of irradiation, both curcumin and complex treatment protected the decline in the levels of GSH, GST, SOD, catalase and total thiols, and inhibited radiation-induced lipid peroxidation. Further, the complex was found to be more effective in protecting the enzymes at 1 h post irradiation compared to curcumin treated group. This may be due to the higher rate constants of the complex compared to curcumin for their reactions with various free radicals. (author)

  10. Evaluation of the effectiveness of gonad protection in diagnostic radiology

    International Nuclear Information System (INIS)

    Kawaura, Chiyo; Aoyama, Takahiko; Koyama, Shuji

    2004-01-01

    In the present study we describes the evaluation of the effectiveness of gonad protection in diagnostic radiology based on the measurement of organ and the effective doses with and without lead clothing to gonads. We devised in-phantom dosimetry system and measured organ and effective doses in x-ray radiography and CT examinations with the new dosimetry system. From the data of organ and the effective doses we assessed the effectiveness of radiological protection by the use of lead clothing to gonads. Although in chest radiography and chest CT examinations, the effectiveness of radiological protection was not found, in the case of hip joint radiography (AP), gonad doses decreased remarkably by using lead clothing. The effectiveness of radiological protection, i.e. the ratio of the decreased dose to the dose value without protection, in testis and ovary were found to be 91.4% and 68.0%, respectively. It was also found that gonad doses observed with and without gonad protection were extremely lower than those of threshold for sterility recommended by the International Commission on Radiological Protection 60 (ICRP Publ. 60). (author)

  11. [Evaluation of the effectiveness of gonad protection in diagnostic radiology].

    Science.gov (United States)

    Kawaura, Chiyo; Aoyama, Takahiko; Koyama, Shuji

    2004-01-01

    In the present study we describe the evaluation of the effectiveness of gonad protection in diagnostic radiology based on the measurement of organ and the effective doses with and without lead clothing to gonads. We devised in-phantom dosimetry system and measured organ and effective doses in x-ray radiography and CT examinations with the new dosimetry system. From the data of organ and the effective doses we assessed the effectiveness of radiological protection by the use of lead clothing to gonads. Although in chest radiography and chest CT examinations, the effectiveness of radiological protection was not found, in the case of hip joint radiography (AP), gonad doses decreased remarkably by using lead clothing. The effectiveness of radiological protection, i.e. the ratio of the decreased dose to the dose value without protection, in testis and ovary were found to be 91.4% and 68.0%, respectively. It was also found that gonad doses observed with and without gonad protection were extremely lower than those of threshold for sterility recommended by the International Commission on Radiological Protection 60 (ICRP Publ. 60).

  12. Recent developments in post-irradiation examination techniques for water reactor fuel. Proceedings of a technical committee meeting held in Cadarache, France, 17-21 October 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    At the invitation of the Government of France, following a proposal of the International Working Group on Water Reactor Fuel Performance and Technology (IWGFPT) the IAEA convened a Technical Committee meeting from 14 to 21 October 1994 in Cadarache to discuss recent technical advances and improvements in the field of post-irradiation examination (PIE) of fuel used in nuclear power plants. Fifty participants representing 14 countries attended the meeting and 30 papers were presented and discussed during five technical sessions. Working Groups composed of the session chairmen and authors of papers prepared summaries of each session including conclusions and recommendations for future work. Refs, figs and tabs.

  13. Recent developments in post-irradiation examination techniques for water reactor fuel. Proceedings of a technical committee meeting held in Cadarache, France, 17-21 October 1994

    International Nuclear Information System (INIS)

    1995-09-01

    At the invitation of the Government of France, following a proposal of the International Working Group on Water Reactor Fuel Performance and Technology (IWGFPT) the IAEA convened a Technical Committee meeting from 14 to 21 October 1994 in Cadarache to discuss recent technical advances and improvements in the field of post-irradiation examination (PIE) of fuel used in nuclear power plants. Fifty participants representing 14 countries attended the meeting and 30 papers were presented and discussed during five technical sessions. Working Groups composed of the session chairmen and authors of papers prepared summaries of each session including conclusions and recommendations for future work. Refs, figs and tabs

  14. Post-irradiation examinations on the KNK II/1 fuel element NY-203 with 400 equivalent full-power days residence time and 10 % burnup

    International Nuclear Information System (INIS)

    Patzer, G.; Geier, F.

    1984-09-01

    The fuel assembly NY-203 has been irradiated in the first core of KNK II up to a burnup of about 10 % and a residence time of 400 equivalent full-power days. The assembly contained 211 fuel pins with 6.0 mm outer diameter and fuel pellets with the composition (U 0 .7Pu 0 .3)O 2 .00. The cladding material was the austenitic steel 1.4988 lg. Some selected pins were examined in the hot cells of the KfK Karlsruhe. The post-irradiation examinations did not reveal any critical design aspects [de

  15. Measurement of the yield and tensile strengths of neutron-irradiated and post-irradiation recovered vessel steels with notched specimens

    International Nuclear Information System (INIS)

    Valiente, A.

    1996-01-01

    Tensile circumferentially notched bars are examined as test specimens for measuring the yield and tensile strengths of nuclear pressure vessel steels under several conditions of irradiation and temperature that a vessel can experience during its service life, including recovery post-irradiation treatment. For all the vessel steels, notch geometries and conditions explored, it has been found that notched specimens fail by plastic collapse, and simple formulae have been derived that allow the yield and tensile strengths to be determined from the yielding and plastic collapse load of a notched specimen. Values measured in this way show good agreement with those measured by the standard tensile test method. (orig.)

  16. Distribution of nuclease attack sites and complexity of DNA in the products of post-irradiation degradiation of rat thymus chromatin

    International Nuclear Information System (INIS)

    Zvonareva, N.B.; Zhivotovsky, B.D.; Hanson, K.P.

    1983-01-01

    The distribution of nuclease attack sites in chromatin has been studied on the basis of the quantitative relationship of the single- and double-stranded fragments of various lengths in the products of post-irradiation degradation of chromatin (PDN). It has been shown that in irradiated thymocytes internucleosome degradation of chromatin occurs and the products of the enzymic digestion of chromatin derive from randomly distributed genome areas accumulate. Analysis of the reassociation curves has not shown any differences in the complexity of the PDN fractions and total DNA. (author)

  17. Protective role of garlic against gamma radiation induced histological and histochemical changes in rat liver

    International Nuclear Information System (INIS)

    Abdel Motaal, N.A.; Abdel Maguid, A.

    2007-01-01

    The present work was planned to evaluate the radioprotective effect of garlic (Allium sativum) against the hazardous action of gamma radiation on liver of rat one and ten days post-exposure. Garlic was orally administered (100 mg/ kg body wt) to rats daily for two weeks before exposure to single dose whole body gamma-irradiation (5Gy). The results showed that exposure of rats to gamma- irradiation caused massive portal infiltration with inflammatory cells, dilatation of blood sinusoids, an increase in the number of Kupffer cells, vacuolation of some hepatocytes as well as pyknosis and karyolysis of hepatic nuclei in the liver tissue. Histochemical examination of liver one day post- irradiation illustrated weak to moderate glycogen particles. While, on ten days post-irradiation, a strong activity for glycogen was detected. The disturbance in carbohydrate metabolism is closely related to the radiation induced histological damage in the liver tissue. Administration of garlic for 2 weeks pre-irradiation reduced the radiation induced histopathological changes and showed marked protection against the tissue damaging effect of radiation. It could be concluded that treatment of rats with garlic before exposure to gamma-irradiation offered a noticeable radioprotective effect of the studied organ

  18. The effect of moisture content within multilayer protective clothing on protection from radiation and steam.

    Science.gov (United States)

    Su, Yun; Li, Jun; Song, Guowen

    2018-06-01

    The moisture from skin sweat and atmospheric water affects the thermal protective performance provided by multilayer protective clothing. Four levels of moisture content were selected to evaluate the impact of moisture on thermal protection under dry (thermal radiation) and wet (thermal radiation and low-pressure steam) heat exposure. Also, the role of moisture and its relationship with exposure time were analyzed based on skin heat flux and Henriques integral value. The addition of moisture to a fabric system was found to result in differences in second-degree and third-degree skin burn times. When moisture is added to a fabric system, it both acts as a thermal conductor to present a negative effect and provides a positive effect owing to thermal storage of water and evaporative heat loss. The positive or negative effects of moisture are mainly dependent on the thermal exposure time, the moisture content and the presence of hot steam.

  19. The protective effect of plasma antioxidants during ozone ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-18

    Jul 18, 2008 ... In this study we investigated the possible protective effects of the plasma antioxidant defense system during O3-AHT. Venous blood from six ..... immune deficiency syndrome (AIDS), and a rationale for ozone therapy and other ...

  20. Protective Effect of Vitamin E on Nicotine Induced Reproductive ...

    African Journals Online (AJOL)

    Protective Effect of Vitamin E on Nicotine Induced Reproductive Toxicity in ... The health implications of cigarette smoking and ..... toxic byproducts of many metabolic processes in ... Male infertility, clinical ... rats: A possible role of cessation.

  1. Protective effect of Ziziphus mauritiana leaf extract on carbon ...

    African Journals Online (AJOL)

    Owner

    2005-09-13

    Sep 13, 2005 ... Short Communication. Protective effect of Ziziphus ... INTRODUCTION. Medicinal plants play a key role in the human health care. About 80% of the world .... McGraw Hill International Edition, London. Gregus Z, Kiwassen C ...

  2. Protective effect of (-)-epigallocatechin gallate on ultraviolet b ...

    African Journals Online (AJOL)

    Purpose: To investigate the protective effect of green tea (-)-epigallocatechin gallate (EGCg) on ultraviolet B (UV-B)-induced skin damages in hairless mice in order to develop a natural sunscreen ... hydrophilic cream has also showed high.

  3. Protective effect of Moringa peregrina leaves extract on ...

    African Journals Online (AJOL)

    Protective effect of Moringa peregrina leaves extract on acetaminophen - induced liver toxicity in albino rats. Samy Abdelfatah Abdel Azim, Mohamed Taha Abdelrahem, Mostafa Mohamed Said, Alshaimaa Khattab ...

  4. Protective effect of Parthenium hysterophorus against carbon ...

    African Journals Online (AJOL)

    admin

    Results: Pre-treatment of rabbits with Ph.Cr reduced ALT, ALP and TB levels (p ... treatment of liver disorders. Because of more effectiveness, less consequences of side effects and low cost, natural remedies are now .... showed hepatocyte necrosis, vacuolization of ..... myocardium, cardiac pacemakers and vascular smooth.

  5. Protective effect of onion extract against experimental ...

    African Journals Online (AJOL)

    Background: The wrong use of drugs results in disturbances in the immunity that affect human health. These drugs have side effects that may lead to death because of lake of immunity. Human beings need to use natural products to strength the immune system and avoid such side effects. Of these products is the onion that ...

  6. Post-irradiation examination of a fuel pin using a microscopic X-ray system: Measurement of carbon deposition and pin metrology

    International Nuclear Information System (INIS)

    Gras, Ch.; Stanley, S.J.

    2008-01-01

    The paper presents some interesting aspects associated with X-ray imaging and its potential application in the nuclear industry. The feasibility of using X-ray technology for the post-irradiation examination of a fuel pin has been explored, more specifically pin metrology and carbon deposition measurement. The non-active sample was specially designed to mimic the structure of an AGR fuel pin whilst a carbon based material was applied to the mock up fuel rod in order to mimic carbon deposition. Short duration low energy (50 kV) 2D digital radiography was employed and provided encouraging results (with respect to carbon deposition thickness and structure measurements) for the mock up fuel pin with a spatial resolution of around 10 μm. Obtaining quantitative data from the resultant images is the principal added value associated with X-ray imaging. A higher intensity X-ray beam (≥90 kV) was also used in conjunction with the low energy set-up to produce a clear picture of the cladding as well as the interface between the lead (Pb mimics the uranium oxide) and stainless steel cladding. Spent fuel metrology and routine radiography are two additional tasks that X-ray imaging could perform for the post-irradiation examination programme. Therefore, when compared to other techniques developed to deliver information on one particular parameter, X-ray imaging offers the possibility to extract useful information on a range of parameters

  7. Strand breaks, base release and post-irradiation changes in DNA γ-irradiated in dilute O2-saturated aqueous solution

    International Nuclear Information System (INIS)

    Ward, J.F.; Kuo, I.

    1976-01-01

    Gamma irradiation of DNA in dilute O 2 -saturated aqueous solution releases free bases and damaged bases from the macromolecule. The yields of these products were measured after column chromatographic separation. For double stranded DNA the immediate yield of bases varies from G = 0.012 for cytosine to G = 0.033 for adenine. The yields of released bases increase with post-irradiation time (the majority of the increase occurs in the first 2 hrs.) to yields in the range of G = 0.07 +- 0.012. Yields of two released damaged thymine radiation products from γ-irradiated 3 H thymine labelled DNA also increased with post-irradiation time. Strand breaks were measured in γ-irradiated single stranded DNA the initial yield G = 0.02 was low but increased with time to G = 0.07. No direct correlation between strand-break production and release of low molecular weight products is possible. The findings are discussed in terms of damage to DNA in vivo and its enzymatic repair

  8. Pulmonary antioxidants exert differential protective effects against ...

    Indian Academy of Sciences (India)

    Unknown

    PM collections from both urban and industrial sites caused 50% oxidative degradation of DNA in vitro at concentrations as low ... chemical analysis in order that progress can be made in ... One popular hypothesis is that PM exerts toxic effects.

  9. Dose dependent sun protective effect of topical melatonin

    DEFF Research Database (Denmark)

    Scheuer, Cecilie; Pommergaard, Hans-Christian; Rosenberg, Jacob

    2016-01-01

    BACKGROUND: Ultraviolet radiation (UVR) by sunlight results in an increasing number of skin conditions. Earlier studies have suggested a protective effect of topical treatment with the pineal hormone melatonin. However, this protective effect has never been evaluated in natural sunlight......-blind study in healthy volunteers. Twenty-three healthy volunteers, 8 male and 15 female, were enrolled. The protective effect of three different doses of melatonin cream (0.5%, 2.5%, 12.5%) against erythema induced by natural sunlight was tested. All participants had their backs exposed to sun from 1:22 PM.......5% concentrations. CONCLUSION: Application of melatonin cream 12.5% protects against natural sunlight induced erythema....

  10. Protective

    Directory of Open Access Journals (Sweden)

    Wessam M. Abdel-Wahab

    2013-10-01

    Full Text Available Many active ingredients extracted from herbal and medicinal plants are extensively studied for their beneficial effects. Antioxidant activity and free radical scavenging properties of thymoquinone (TQ have been reported. The present study evaluated the possible protective effects of TQ against the toxicity and oxidative stress of sodium fluoride (NaF in the liver of rats. Rats were divided into four groups, the first group served as the control group and was administered distilled water whereas the NaF group received NaF orally at a dose of 10 mg/kg for 4 weeks, TQ group was administered TQ orally at a dose of 10 mg/kg for 5 weeks, and the NaF-TQ group was first given TQ for 1 week and was secondly administered 10 mg/kg/day NaF in association with 10 mg/kg TQ for 4 weeks. Rats intoxicated with NaF showed a significant increase in lipid peroxidation whereas the level of reduced glutathione (GSH and the activity of superoxide dismutase (SOD, catalase (CAT, glutathione S-transferase (GST and glutathione peroxidase (GPx were reduced in hepatic tissues. The proper functioning of the liver was also disrupted as indicated by alterations in the measured liver function indices and biochemical parameters. TQ supplementation counteracted the NaF-induced hepatotoxicity probably due to its strong antioxidant activity. In conclusion, the results obtained clearly indicated the role of oxidative stress in the induction of NaF toxicity and suggested hepatoprotective effects of TQ against the toxicity of fluoride compounds.

  11. Protective Effects of Tetrahydrocurcumin and Curcumin against ...

    African Journals Online (AJOL)

    Purpose: To investigate the cytoprotective effect of tetrahydrocurcumin, (THC) and curcumin (CUR) on cytotoxicity induced by doxorubicin and cadmium in Chang liver cells. Methods: Cytotoxicity was determined by sulforhodamine B assay. The expression of nuclear factorerythroid- 2-related factor 2 (Nrf2) Nrf2 regulated ...

  12. Pinoresinol diglucoside exhibits protective effect on dexamethasone ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of pinoresinol diglucoside (PDG) on dexamethasone-induced osteoporosis in rats. Methods: Sixty Wistar rats were randomly and equally divided into normal, control, alendronate and PDG (10, 20 or 40 mg/kg) groups. Bone tissue parameters, including length, transverse diameter, weight, ...

  13. Skin Protective Effect of Epigallocatechin Gallate

    Directory of Open Access Journals (Sweden)

    Eunji Kim

    2018-01-01

    Full Text Available Epigallocatechin gallate (EGCG is a catechin and an abundant polyphenol in green tea. Although several papers have evaluated EGCG as a cosmetic constituent, the skin hydration effect of EGCG is poorly understood. We aimed to investigate the mechanism by which EGCG promotes skin hydration by measuring hyaluronic acid synthase (HAS and hyaluronidase (HYAL gene expression and antioxidant and anti-pigmentation properties using cell proliferation assay, Western blotting analysis, luciferase assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH assay, and reverse transcription polymerase chain reaction (RT-PCR analysis. RT-PCR showed that EGCG increased the expression of natural moisturizing factor-related genes filaggrin (FLG, transglutaminase-1, HAS-1, and HAS-2. Under UVB irradiation conditions, the expression level of HYAL was decreased in HaCaT cells. Furthermore, we confirmed the antioxidant activity of EGCG and also showed a preventive effect against radical-evoked apoptosis by downregulation of caspase-8 and -3 in HaCaT cells. EGCG reduced melanin secretion and production in melanoma cells. Together, these results suggest that EGCG might be used as a cosmetic ingredient with positive effects on skin hydration, moisture retention, and wrinkle formation, in addition to radical scavenging activity and reduction of melanin generation.

  14. Protective Effect against Oxidative Stress in Medicinal Plant Extracts

    International Nuclear Information System (INIS)

    Kim, Jeong Hee; Lee, Eun Ju; Shin, Dong O; Hong, Sung Eun; Kim, Jin Kyu

    2000-01-01

    Protective effect of medicinal plant extracts against oxidative stress were screened in this study. Methanol extracts from 48 medicinal plants, which were reported to have antioxidative or anti-inflammatory effect were prepared and screened for their protective activity against chemically-induced and radiation-induced oxidative stress by using MTT assay. Thirty three samples showed protective activity against chemically-induced oxidative stress in various extent. Among those samples, extract of Glycyrrhiza uralensis revealed the strongest activity (25.9% at 100 μg/ml) with relatively lower cytotoxicity. Seven other samples showed higher than 20% protection at 100 μg/ml. These samples were tested for protection activity against radiation-induced oxidative stress. Methanol extract of Alpina officinarum showed the highest activity (17.8% at 20 μg/ml). Five fractions were prepared from the each 10 methanol extracts which showed high protective activity against oxidative stress. Among those fraction samples butanol fractions of Areca catechu var. dulcissima and Spirodela polyrrhiza showed the highest protective activities (78.8% and 77.2%, respectively, at 20 μg/ml)

  15. The effect of impact modifier and of nucleating agent on the radiation tolerance of polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Liu Dongyuan (Beijing Normal Univ., BJ (China)); Czvikovszky, T.; Dobo, J.; Somogyi, A. (Research Inst. for the Plastics Industry, Budapest (Hungary))

    1990-01-01

    The effect of two types of additives was investigated with respect to the oxidative post-irradiation stability of polypropylene: SBS thermoplastic rubbers as impact modifiers and benzoic acid as nucleating agent. Testing was performed by ultimate deformation on bending. The thermoplastic rubber additive increased the post-irradiation stability of polypropylene substantially. (author).

  16. The effect of impact modifier and of nucleating agent on the radiation tolerance of polypropylene

    International Nuclear Information System (INIS)

    Liu Dongyuan; Czvikovszky, T.; Dobo, J.; Somogyi, A.

    1990-01-01

    The effect of two types of additives was investigated with respect to the oxidative post-irradiation stability of polypropylene: SBS thermoplastic rubbers as impact modifiers and benzoic acid as nucleating agent. Testing was performed by ultimate deformation on bending. The thermoplastic rubber additive increased the post-irradiation stability of polypropylene substantially. (author)

  17. Protective Effect of Chitin Urocanate Nanofibers against Ultraviolet Radiation

    Directory of Open Access Journals (Sweden)

    Ikuko Ito

    2015-12-01

    Full Text Available Urocanic acid is a major ultraviolet (UV-absorbing chromophore. Chitins are highly crystalline structures that are found predominantly in crustacean shells. Alpha-chitin consists of microfibers that contain nanofibrils embedded in a protein matrix. Acid hydrolysis is a common method used to prepare chitin nanofibrils (NFs. We typically obtain NFs by hydrolyzing chitin with acetic acid. However, in the present study, we used urocanic acid to prepare urocanic acid chitin NFs (UNFs and examined its protective effect against UVB radiation. Hos: HR-1 mice coated with UNFs were UVB irradiated (302 nm, 150 mJ/cm2, and these mice showed markedly lower UVB radiation-induced cutaneous erythema than the control. Additionally, sunburn cells were rarely detected in the epidermis of UNFs-coated mice after UVB irradiation. Although the difference was not as significant as UNFs, the number of sunburn cells in mice treated with acetic acid chitin nanofibrils (ANFs tended to be lower than in control mice. These results demonstrate that ANFs have a protective effect against UVB and suggest that the anti-inflammatory and antioxidant effects of NFs influence the protective effect of ANFs against UVB radiation. The combination of NFs with other substances that possess UV-protective effects, such as urocanic acid, may provide an enhanced protective effect against UVB radiation.

  18. Could caffeine have some vaso protective effect?

    International Nuclear Information System (INIS)

    Buitrago, Lorena; Barrera, Gladys; Zuniga, Carolina and others

    2004-01-01

    Coffee is the most consumed hot drink in the world. it is part of the current and cultural diet of our society. There is a myth around coffee, considering it injurious based on clinical studies, whose results have been contradictory and without a solid scientific support. Nevertheless, in the last few years, there have been studies that describe the kindness of the coffee upon convecting, digestive and cardiovascular system. We want to present the vasodilator effect of caffeine in a experimental model that used aorta rings of normal and hipercholesterolemic rabbits, mounted in a organ bath system (Kent scientific corporation, Litchfield CT containing krebs, solution. The solution was kept at 37 Celsius degrade and aerated continuously with a 95% o 2 5% CO 2 gas mixture. The rings were pre contracted with norepinephrine (-5.5 log m) and relaxed with nitroglycerin (endothelium independent relaxation), acetylcholine (endothelium dependant relaxation) and caffeine

  19. Research on radiation effect and radiation protection at JAEA

    International Nuclear Information System (INIS)

    Saito, Kimiaki

    2007-01-01

    Researches on radiation effect and radiation protection at JAEA have been carried out in different sections. In recent years, the organizations were rearranged to attain better research circumstances, and new research programs started. At present, radiation effect studies focus on radiation effect mechanisms at atomic, molecular and cellular levels including simulation studies, and protection studies focus on dosimetry for conditions difficult to cover with currently used methods and data as well as the related basic studies. The outlines of the whole studies and also some descriptions on selected subjects will be given in this paper. (author)

  20. The ecological effectiveness of protected areas: the United Kingdom

    NARCIS (Netherlands)

    Gaston, K.J.; Charman, K.; Jackson, S.F.; Armsworth, P.R.; Bonn, A.; Briers, R.A.; Callaghan, C.S.Q.; Catchpole, R.; Hopkins, J.; Kunin, W.E.; Latham, J.; Opdam, P.F.M.; Stoneman, R.; Stroud, D.A.; Tratt, R.

    2006-01-01

    Given the importance placed on protected areas, determining their effectiveness in representing and maintaining biodiversity is a core issue in conservation biology. Nonetheless, frameworks identifying the breadth of issues associated with this effectiveness, and case studies of how well these are

  1. The protective effect of plasma antioxidants during ozone ...

    African Journals Online (AJOL)

    Ozone (O3) therapy forms part of a group of complementary and alternative medical therapies and is gaining more and more interest worldwide. There is, however, some concern regarding O3-toxicity and uncertainty about the effectiveness of O3-therapy. In this study we investigated the possible protective effects of the ...

  2. Protective effect of Carica papaya fruit extract against gamma ...

    African Journals Online (AJOL)

    Radiation side effects have been reported to induce oxidative stress by free radical generation. The protective effect of Carica papaya (CP) fruit extract, vitamins C and E against gamma radiation-induced oxidative damage on postnatal developing rat cerebellum was studied. Forty-two female Wistar rats were mated and ...

  3. Management effectiveness evaluation in protected areas of southern Ecuador.

    Science.gov (United States)

    López-Rodríguez, Fausto; Rosado, Daniel

    2017-04-01

    Protected areas are home to biodiversity, habitats and ecosystem as well as a critical component of human well-being and a generator of leisure-related revenues. However, management is sometimes unsatisfactory and requires new ways of evaluation. Management effectiveness of 36 protected areas in southern Ecuador have been assessed. The protected areas belong to three categories: Heritage of Natural Areas of the Ecuadorian State (PANE), created and funded by the State, Areas of Forest and Protective Vegetation (ABVP), created but no funded by the State, and private reserves, declared and funded by private entities. Management effectiveness was evaluated by answers of managers of the protected areas to questionnaires adapted to the socio-economic and environmental characteristics of the region. Questions were classified into six elements of evaluation: context, planning, inputs, processes, outputs and outcomes as recommended by IUCN. Results were classified into four levels: unsatisfactory, slightly satisfactory, satisfactory and very satisfactory. The PANE areas and private reserves showed higher management effectiveness levels (satisfactory and very satisfactory) than ABVP areas, where slightly satisfactory and unsatisfactory levels prevailed. Resources availability was found as the main reason behind this difference. The extension, age and province of location were found irrelevant. Outputs, inputs and processes require main efforts to improve management effectiveness. Improving planning and input in the PANE areas and inputs and outcomes on ABVP areas is necessary to obtain a similar result in all areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. [Methods of gonad protection against effects of chemotherapy].

    Science.gov (United States)

    Kowalska, A

    1994-05-01

    Together with increasing therapeutic effectiveness neoplastic diseases, the interest in late consequences of adverse effects of chemotherapy is increasing. Such problems include disturbances of gonad function. Treatment of neoplastic diseases leads frequently to infertility and hormonal disturbances resulting from damages to the gonads. Many attempts have been undertaken at protection of the gonads against unfavourable action of drugs. They are based mainly on the "interruption" of the hypothalamo-hypophyseo-gonadal axis in order to make the gonads quiescent. Other direction includes the influence on the metabolism of oncological drugs aimed at inhibition of the development of gonadotoxic derivatives. Another method includes appropriate choice of cytostatics: antimetabolites exert weaker unfavourable action on the gonads than alkylating drugs. The problem of gonad protection remains open. Searching is necessary for drugs without gonadotoxic action and effective methods of protection.

  5. Power-to-melt evaluation of fresh mixed-oxide fast reactor fuel. Technical improvements of the post-irradiation-experiment and the evaluation of the results for the power-to-melt test PTM-2 in 'JOYO'

    International Nuclear Information System (INIS)

    Yamamoto, Kazuya; Kushida, Naoya; Koizumi, Atsuhiro

    1999-11-01

    The second Power-To-Melt (PTM) test, PTM-2, was performed in the experimental fast reactor 'JOYO'. All of the twenty-four fuel pins of the irradiation vehicle, B5D-2, for the PTM-2 test, were provided for post-irradiation-experiment (PIE) to evaluate the PTM values. In this study, the PIE technique for PTM test was established and the PTM results were evaluated. The findings are as follows: The maximum fuel-melting ratio on the transverse section was 10.7%, and was within the limit of fuel-melting in this PTM test enough. Unexpected fuel-melting amount to a ratio of 11.8% was found at ∼24 mm below the peak power elevation in a test fuel pin. It is possible that this arose from secondary fuel-melting. Combination of metallographical observation with X-ray microanalysis of plutonium distribution was very effective for the identification of once-molten fuel zone. The PTM evaluation suggested that dependence of the PTM on the fuel pellet density was stronger than that of previous foreign PTM tests, while the dependence on the pellet-cladding gap and the oxygen-to-metal ratio was indistinctly. The dependence on the cladding temperature and the fill gas composition was not shown as well. (author)

  6. Gamma-ray irradiation and post-irradiation at room and elevated temperature response of pMOS dosimeters with thick gate oxides

    Directory of Open Access Journals (Sweden)

    Pejović Momčilo M.

    2011-01-01

    Full Text Available Gamma-ray irradiation and post-irradiation response at room and elevated temperature have been studied for radiation sensitive pMOS transistors with gate oxide thickness of 100 and 400 nm, respectively. Their response was followed based on the changes in the threshold voltage shift which was estimated on the basis of transfer characteristics in saturation. The presence of radiation-induced fixed oxide traps and switching traps - which lead to a change in the threshold voltage - was estimated from the sub-threshold I-V curves, using the midgap technique. It was shown that fixed oxide traps have a dominant influence on the change in the threshold voltage shift during gamma-ray irradiation and annealing.

  7. The second Euratom sponsored 9000C HTR fuel irradiation experiment in the HFR Petten Project E 96.02: Pt.2. Post-irradiation examination

    International Nuclear Information System (INIS)

    Roettger, R.; Bueger, J. de; Schoots, T.

    1977-01-01

    A large variety of HTR fuel specimens, loose coated particles, coupons and compacts provided by Belgonucleaire, the Dragon Project and the KFA Juelich have been irradiated in the HFR at Petten at about 900 0 C up to a maximum fast neutron fluence of about 7x10 21 cm -2 (EDN) as a Euratom sponsored experiment. The maximum burn-ups were between 11 and 18.5% FIMA. The results of the post-irradiation examinations, comprising visual inspection, dimensional measurements, microradiography, metallography, and burn-up determinations are presented in this part 2 of the final report. The examinations have shown that the endurance limit of most of the tested fuel varieties is beyond the reached irradiation values

  8. Examples of CEA managements of spent fuels from a prototype power reactor (PHENIX) and from commercial power reactors after post irradiation examinations

    International Nuclear Information System (INIS)

    Guay, P.

    1988-01-01

    CEA gained a good experience in the management of spent fuels from its research or power prototype reactors and of the fuel samples for post irradiation examinations. The solution for these products is the reprocessing. The delay to apply that solution is bound to the disponibility of the reprocessing facilities, and in several cases induce a delayed reprocessing. Only particular and limited fuels are planned to be sent in a definitive storage. The definitive storage is choosen only for a few fuels essentially requiring important modifications of the dissolution process. The treatments and operations on the spent fuels must be carried out following the French safety rules. Long and detailed flowsheet studies are therefore necessary before the setting up of the operations. Generally the cost of the management of limited quantities of fuels, as it is the case here, is high. The flowsheets are established in taking into account, as far as possible, the use of existing facilities, procedures, transport casks

  9. Alexandre - a multi-project, multi-material and multi-technique action for an irradiation experiment in Osiris and post irradiation examination

    International Nuclear Information System (INIS)

    Averty, X.; Brachet, J.C.; Bertin, J.L.; Pizzanelli, J.P.; Rozenblum, F.

    1999-01-01

    This paper presents the data obtained on different classes of steels neutron irradiated at 325 deg C in pressurized water with a PWR-type chemistry. This irradiation, nicknamed 'Alexandre', took place in the OSIRIS reactor and finished in November 1999, for a maximum irradiation damage of ∼9 dpa. The preliminary results (up to 3.4 dpa), discussed in relation to chemical composition and initial metallurgical conditions, are listed below: - Evolution of the mechanical properties as a function of irradiation dose including the measurements of the Reduction-in-Area to failure by image analysis. - Comparison between out-of-pile and in-pile uniform corrosion. - Microstructural aspects (fractography, Transmission Electron Microscopy, and Small Angle Neutron Scattering measurements). - Post-irradiation evolution of residual. activity. (authors)

  10. Program description for the qualification of CNEA - Argentina as a supplier of LEU silicide fuel and post-irradiation examinations plan for the first prototype irradiated in Argentina

    International Nuclear Information System (INIS)

    Rugirello, Gabriel; Adelfang, Pablo; Denis, Alicia; Zawerucha, Andres; Marco, Agustin di; Guillaume, Eduardo; Sbaffoni, Monica; Lacoste, Pablo

    1998-01-01

    In this report we present a description of the ongoing and future stages of the program for the qualification of CNEA, Argentina, as a supplier of low enriched uranium silicide fuel elements for research reactor. Particularly we will focus on the characteristics of the future irradiation experiment on a new detachable prototype, the post-irradiation examinations (PIE) plan for the already irradiated prototype PO4 and an overview of the recently implemented PIE facilities and equipment. The program is divided in several steps, some of which have been already completed. It concludes: development of the uranium silicide fissile material, irradiation and PIE of several full-scale prototypes. Important investments have been already carried out in the facilities for the FE production and PIE. (author)

  11. Synthesis and characterization polymer composites prepared by low-temperature post-irradiation polymerization of C_2F_4 in the presence of graphene-like material

    International Nuclear Information System (INIS)

    Shulga, Y.M.; Kiryukhin, D.P.; Vasilets, V.N.

    2015-01-01

    Polymer polytetrafluoroethylene (Ptfe)-microwave exfoliated graphene oxide (MEGO) composites containing up to 80 wt.% PTFE were prepared by low-temperature post-irradiation polymerization of C_2F_4 in the presence of the graphene-like material. Composites were characterized by elemental analysis, XPS, NMR, and DSC techniques. The melting point of PTFE in the composite (332.5°C) was higher than that of pure PTFE by 8.8°C. The measured values of the melting enthalpy (ΔHm=51.5 and 45.4 J/g) were used to calculate the extent of crystallinity in the PTFE and PTFE-MEGO composite (0.63 and 0.55, respectively). No - CF_3 end groups typical of commercial PTFE have been detected in the PTFE-MEGO composites. (authors)

  12. Neutron activation analysis with pre- and post-irradiation chemical separation for the value assignments of Al, V, and Ni in the new bovine liver SRM 1577C

    International Nuclear Information System (INIS)

    Zeisler, R.; Tomlin, B.E.; Murphy, K.E.

    2009-01-01

    Instrumental neutron activation analysis as carried out at the National Institute of Standards and Technology (NIST) is inadequate for determining Al, Ni, and V at the levels found in the newly prepared Standard Reference Material R (SRM) 1577c Bovine Liver. To overcome shortcomings in the value assignment, the authors initiated a cooperative approach using NAA with previously established chemical separation procedures and with significantly different neutron energy spectra to determine Al and V with pre-irradiation separation of the elements at NIST, and V and Ni with post-irradiation separation at the Nuclear Physics Institute Rez. The determinations were confirmed with the analyses of several SRMs. The work supported the certification of mass fraction values for V and Ni in SRM 1577c. (author)

  13. 133Xe release during post-irradiation annealing of uranium metal in the presence of a constant volume of air Pt. 1

    International Nuclear Information System (INIS)

    Marei, S.A.; El-Garhy, M.; El-Bayoumy, S.; Muenze, R.; Hladik, O.

    1978-01-01

    The fractional release of 133 Xe at different temperatures was studied as a function of time in the presence of air during post-irradiation annealing of uranium metal. The relation between the fractional release and tsup(1/2) was found to be irregular. There is an initial step in the annealing curves (at the temperature range of 400-710 deg C) which decreases by increasing temperature and totally disappears at the high temperature of 800-1000 deg C. The initial step was found to be due to the surface oxidation of uranium metal. The other two parts of the release curves are normal for 133 Xe release from uranium metal. Since in this work the irradiation temperature is low ( 133 Xe. (T.G.)

  14. Evaluation on effects of isradipine on renal protection by SPECT

    International Nuclear Information System (INIS)

    Xu Fengpo; Dong Shenan; Zhang Wei; Wu Xinghong; Lu Guoyuan

    1999-01-01

    The protective effects of isradipine on renal function were evaluated in a study on 40 patients with mild-moderate essential hypertension. Isradipine was administered at ado-sage of 2.5 mg twice daily for 4 weeks after receiving placebo for one week. SPECT were used for detecting renal function. The results of these evaluation indicated that there was significantly increasing in ERPF and GFR (P<0.01) and significant decreasing in resistance of renal vessel (P<0.01), and FF remained unchanged. It suggests that isradipine has a protective effect on renal function and it is beneficial for the long-term therapy

  15. Protective Effect of HemoHIM on Epidermal Melanocytes in Ultraviolet-B irradiated Mice

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hae June [Korea Institute of Radiological and Medical Science, Seoul (Korea, Republic of); Kim, Jong Choon; Moon, Chang Jong; Kim, Sung Ho [Chonnam National University, Gwangju (Korea, Republic of); Jung, U Hee; Park, Hae Ran; Jo, Sung Kee [Jeongeup Campus of Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Jang, Jong Sik; Kim, Tae Hwan [Kyungpook National University, Daegu (Korea, Republic of)

    2011-06-15

    We induced the activation of melanocytes in the epidermis of C57BL/6 mice by ultraviolet-B (UV-B) irradiation, and observed the effect of an herbal preparation (HemoHIM, HH) on the formation, and decrease of UV-B-induced epidermal melanocytes. C57BL/6 mice were irradiated by UV-B 80 mJ:cm{sup -2} (0.5 mW:sec{sup -1}) daily for 7 days, and HH was intraperitoneally, orally or topically applied pre- or post-irradiation. For the estimation of change of epidermal melanocytes, light microscopic observation with dihydroxyphenylalanine (DOPA) stain was performed. Split epidermal sheets prepared from the ear of untreated mice exhibited 13∼15 melanocytes:mm{sup -2}, and one week after UV irradiation, the applied areas showed an increased number of strongly DOPA-positive melanocytes with stout dendrites. But intraperitoneal, oral or topical treatment with HH before each irradiation interrupted UV-B-induced pigmentation and resulted in a marked reduction in the number of epidermal melanocytes as compared to the number found in UV-B-irradiated, untreated control skin. The number and size of DOPA-positive epidermal melanocytes were also significantly decreased in intraperitoneally injected or topically applicated group after irradiation with HH at 3rd and 6th weeks after irradiation. The present study suggests the HH as inhibitor of UV-B-induced pigmentation, and depigmenting agent.

  16. Protective effect of Adeturone on E.coli survival

    International Nuclear Information System (INIS)

    Baldzhijska, M.; Minkova, M.; Pantev, T.

    1980-01-01

    Antiradiation potencies of AET, ATP, and the preparation Adeturone (AET salt of ATP) were studied in terms of E.coli survival following exposure to gamma-ray doses ranging from 1.29 K/kg to 20.64 K/kg AET was found to provide protection only in the case of the highest of three concentrations used, 625 micrograms per milliliter. ATP concentrations of 587 mcg/ml proved ineffective whether used solely or in a mixture with 262.5 mcg/ml of AET. These ineffective AET and ATP concentrations are equimolar with the amounts of AET and ATP contained in Adeturone. The latter showed a protective effect when applied at 625 mcg/ml, but failed to protect at a lower (312 mcg/ml) or at higher (1250 mcg/ml and 1500 mcg/ml) concentrations. Confirmative evidence was thus obtained that chemical binding of the two protectors raises the effectiveness of the combination

  17. In the Name of Effective Consumer Protection and Public Policy!

    DEFF Research Database (Denmark)

    Sørensen, Marie Jull

    2016-01-01

    I. The CJEU has established that under certain circumstances national courts have an obligation, ex officio, to apply specific consumer protection provisions. This article presents a model derived from the argumentation for this obligation in CJEU case law. The model consists of four steps...... that include the specific ideas behind consumer protection provisions as well as the interaction between the principle of effectiveness and principle of equivalence. It is found that the principle of effectiveness is stretched very long and is often not set aside by the “rule of reason”. It is also found...... that the CJEU is open to the idea of regarding consumer protection provisions as (EU) public policy rules which seems to challenge the traditional principle of equivalence. Based on the findings, the author elaborates on the concept of an European public policy doctrine....

  18. Protective effect of Adeturone on E. coli survival

    Energy Technology Data Exchange (ETDEWEB)

    Baldzhijska, M; Minkova, M; Pantev, T [Meditsinska Akademiya, Sofia (Bulgaria). Nauchen Inst. po Rentgenologiya i Radiobiologiya

    1980-01-01

    Antiradiation potencies of AET, ATP, and the preparation Adeturone (AET salt of ATP) were studied in terms of E.coli survival following exposure to gamma-ray doses ranging from 1.29 K/kg to 20.64 K/kg AET was found to provide protection only in the case of the highest of three concentrations used, 625 micrograms per milliliter. ATP concentrations of 587 mcg/ml proved ineffective whether used solely or in a mixture with 262.5 mcg/ml of AET. These ineffective AET and ATP concentrations are equimolar with the amounts of AET and ATP contained in Adeturone. The latter showed a protective effect when applied at 625 mcg/ml, but failed to protect at a lower (312 mcg/ml) or at higher (1250 mcg/ml and 1500 mcg/ml) concentrations. Confirmative evidence was thus obtained that chemical binding of the two protectors raises the effectiveness of the combination.

  19. Protective effect of lead aprons in medical radiology

    International Nuclear Information System (INIS)

    Huyskens, C.J.

    1995-01-01

    This article summarizes the results of an ongoing study regarding the protective effect that lead aprons, as used in medical radiology, have on the resulting effective dose for medical personnel. By means of model calculations we have analyzed the protection efficacy of lead aprons for various lead thicknesses, in function of tube potential and of variations in exposure geometry as they occur in practice. The degree of efficacy appears to be highly dependent on the fit of aprons because of the dominating influence of the equivalent dose of partially unshielded organs on the resulting effective dose. Also by model calculations we investigated the ratio between the effective dose and the operational quantify for personal dose monitoring. Our study enables the choice of appropriate correction factors for convering personal dosimetry measurements into effective dose, for typical exposure situations in medical radiology. (orig.) [de

  20. Swazi men's perception of the protective effect of male circumcision ...

    African Journals Online (AJOL)

    about the protective effect of circumcision against STIs including HIV, and its implication to the mass MC strategy. .... In addition, permission to conduct the study was also granted by the FLAS Research and Evaluation Unit. ..... Willingness to be circumcised for preventing HIV among Chinese men who have sex with men.

  1. Protective Effect of Purple Sweet Potato (Ipomoea batatas Linn ...

    African Journals Online (AJOL)

    Purpose: To evaluate the protective effects of purple sweet potato (Ipomoea batatas Linn, Convolvulaceae) extract (IBE) in stimulated BV-2 microglial cells and its anti-oxidant properties. Methods: Cell viability assessment was performed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5- diphenyltetrazolium bromide (MTT) assay.

  2. Effects of rumen-protected tryptophan on performance, nutrient ...

    African Journals Online (AJOL)

    Jane

    2011-06-27

    Jun 27, 2011 ... sources high in rumen-protected Trp (RPT) can be fed to complement the ... collected into plastic containers containing 50 ml of 50% HCl to prevent NH3 .... growth, higher Trp availability could have exerted an effect also on ...

  3. Protective Effects of Aqueous Extract of Sempervivum tectorum L ...

    African Journals Online (AJOL)

    Protective Effects of Aqueous Extract of Sempervivum tectorum L ( Crassulaceae ) on Aluminium-Induced Oxidative Stress in Rat Blood. ... Results: Aluminium (Al) exposure increased, compared to control group, the level of blood Al (293.64 %, p 0.05), glutathione ...

  4. Safety and protective effect of Lactobacillus acidophilus and ...

    African Journals Online (AJOL)

    The protective effect of Lactobacillus acidophilus and Lactobacillus casei, isolated from fresh cow milk, was studied in vivo. Toxicological data of rat serum revealed that the Lactobacillus isolates had liver improvement functions. Serum alanine aminotransferase (ALT) activities of the rats dosed with Lactobacillus isolates ...

  5. Protective Effect of Vitamin E on Nicotine Induced Reproductive ...

    African Journals Online (AJOL)

    The current study assessed the protective role of vitamin E in alleviating the detrimental effect of nicotine on reproductive functions in male rats. Twenty four male albino rats were divided into four groups of six rats. Control group was treated orally with 1.1 ml/kg body weight normal saline, nicotine treated group received 1.0 ...

  6. Protective effect of (-)-epigallocatechin gallate on ultraviolet b ...

    African Journals Online (AJOL)

    ... EGCg shows dose-dependent protective effect against UV-B-induced damage on hairless mouse skin. Thus, the plant compound can potentially be used as an alternative agent for photoprotection against UV-B exposure. Keywords: UV-B, Green tea EGCg, Photoprotection, Stratum corneum, Mitochondrion, Melanosome ...

  7. Protective effect of vanillic acid on ovariectomy-induced ...

    African Journals Online (AJOL)

    Background: The need for an anti-osteoporotic agent is in high demand since osteoporosis contributes to high rates of disability or impairment (high osteoporotic fracture), morbidity and mortality. Hence, the present study is designed to evaluate the protective effects of vanillic acid (VA) against bilateral ovariectomy-induced ...

  8. The reno-protective effects of dietary caloric restriction against ...

    African Journals Online (AJOL)

    Studies have shown that dietary caloric restriction (CR) without malnutrition can increase longevity. This study aims to evaluate the protective effects of CR on oxidative stress, lipid peroxidation and inflammatory cytokines in the kidney of streptozotocin-induced diabetic rats. Forty 12-week old male Wistar rats, weighing ...

  9. The protective effects of good parenting on adolescents.

    Science.gov (United States)

    DeVore, Elise R; Ginsburg, Kenneth R

    2005-08-01

    To explore recent developments in the literature regarding parenting practices and adolescent development, with a focus on parenting style, parental monitoring, communication, and supervision. There have been significant recent advances in the study of the relationship between parenting and adolescent development. Several recent intervention studies with a parenting component demonstrated immediate and long-term protective effects on adolescent risk behavior. Parent-child connectedness and authoritative parenting style are protective for teens. Parental monitoring has a protective effect on many adolescent risk behaviors in both middle-class populations and poor urban environments and has been shown both to moderate the effect of peer influence and to persist into late adolescence. Whereas unsupervised time, exposure to sexual possibility situations, and out-of-home care increase sexual behavior, improved parent-child communication reduces sexual risk behaviors. Recent scholarship demonstrates the significant, enduring, and protective influence of positive parenting practices on adolescent development. In particular, parental monitoring, open parent-child communication, supervision, and high quality of the parent-child relationship deter involvement in high-risk behavior. Authoritative parenting generally leads to the best outcomes for teens. Clinicians should find opportunities to discuss evidence-based parenting practices with families. Future research should focus on the development and long-term evaluation of effective parenting interventions.

  10. Protective Effect of Bombyx mori L Cocoon (Abresham) and its ...

    African Journals Online (AJOL)

    HP

    Protective Effect of Bombyx mori L Cocoon (Abresham) and its ... agonist, at high doses, has been reported to produce ... 12:12 h. Standard pellet diet and tap water were ... induction of myocardial injury on the scheduled ... Total protein in of B. mori cocoon (Abresham) ..... The authors thank Professor SK Maulik, Head,.

  11. Qualitative and quantitative radiation protection analysis of mucosa of ICR strained mice using selected herbal extracts such as GC-2112 from garlic (Allium sativum) and GX-2137 from ginseng (Panax sp.)

    International Nuclear Information System (INIS)

    Bunagan, J.B.

    2005-01-01

    Full text: Earlier reports showed that ginseng has significant radioprotective and stimulatory effect on the recovery of the lymphocytes and leukocytes. Using graded absorbed doses of radiation (1.5, 5, 20, 50 Gy) applied in ICR strain male white mice which was injected with GX-2137 from ginseng (Panax sp.) and GC-2112 from garlic (Allium sativum) was tested to prove some radioprotective efficiency. The herbal extracts were injected intraperitoneally and the experimental mice were sacrificed 2 and 48 hrs post-irradiation. Factors such as analyzing kinetics of critical tissue parameters (length of villi, the number of crypt and villi cells and cell density) and determining the Relative Protection Efficiencies (RPE) using quantitative histopathological techniques were used to quantify the radiation protection assay in the duodenum of ICR strain mice. Results showed that GC-2112 and GX-2137 protected the villi structures. After 2 hrs. post irradiation, tissue degeneration was evident. RPE values of significant radioprotection of the crypts is demonstrated at absorbed dose. It was found that some villi cells are even viable at non-physiologic dose of 50 Gy. (author)

  12. Review of the effects of protection in marine protected areas: current knowledge and gaps

    Directory of Open Access Journals (Sweden)

    Ojeda–Martínez, C.

    2011-06-01

    Full Text Available The effectiveness of marine protected areas (MPAs and the conservation of marine environments must be based on reliable information on the quality of the marine environment that can be obtained in a reasonable timeframe. We reviewed studies that evaluated all aspects related to the effectiveness of MPAs in order to describe how the studies were conducted and to detect fields in which research is lacking. Existing parameters used to evaluate the effectiveness of MPAs are summarised. Two-hundred and twenty-two publications were reviewed. We identified the most commonly used study subjects and methodological approaches. Most of the studies concentrated on biological parameters. Peer reviewed studies were based on control vs. impact design. BACI and mBACI designs were used in very few studies. Through this review, we have identified gaps in the objectives assigned to MPAs and the way in which they have been evaluated. We suggest some guidelines aimedat improving the assessment of the effects of protection in MPAs.

  13. Quantitative evaluation of the protective effect of respirators

    International Nuclear Information System (INIS)

    Murata, Mikio

    1983-01-01

    The present status and related problems of the quantitative evaluation method for respirator efficiency are generally reviewed. As the introduction, the special features of various types of respirators are summarized, and the basic concept of leakage and the protection factor are explained. As for the quantitative measurement of the protective efficiency, the features of various existing man-test methods such as NaCl aerosol man-test, DOP (dioctyl phthalate) man-test, and SF 6 gas man-test are reviewed and discussed. As the important problems associated with those man-tests, the following aspects are discussed. The measurement of the aerosol concentration within masks; the calculation method for the protection factor; the effect of beards. The examples of measuring the protection factor are also explained for the following respirator systems: half mask respirator with a high efficiency filter; full face mask respirator with a high efficiency filter; demand mode and pressure-demand mode respirators; and mound suit with suspenders. Finally, the outline of the manual of respiratory protection published by NRC in 1976 is briefly reviewed. (Aoki, K.)

  14. Differential protective effects of motorcycle helmets against head injury.

    Science.gov (United States)

    Singleton, Michael D

    2017-05-19

    Although numerous observational studies have demonstrated a protective effect of motorcycle helmets against head injury, the degree of protection against specific head injury types remains unclear. Experimental biomechanics studies involving cadavers, animals, and computer models have established that head injuries have varying etiologies. This retrospective cross-sectional study compared helmet protection against skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion in a consecutive series of motorcycle operators involved in recent traffic crashes in Kentucky. Police collision reports linked to hospital inpatient and emergency department (ED) claims were analyzed for the period 2008 to 2012. Motorcycle operators with known helmet use who were not killed at the crash scene were included in the study. Helmet use was ascertained from the police report. Skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion were identified from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes on the claims records. The relative risks of each type of head injury for helmeted versus unprotected operators were estimated using generalized estimating equations. Helmets offer substantial protection against skull fracture (relative risk [RR] = 0.31, 95% confidence interval [CI], 0.23, 0.34), cerebral contusion (RR = 0.29, 95% CI, 0.16, 0.53), and intracranial hemorrhage (RR = 0.47, 95% CI, 0.35, 0.63). The findings pertaining to uncomplicated concussion (RR = 0.80, 95% CI, 0.64, 1.01) were inconclusive. A modest protective effect (20% risk reduction) was suggested by the relative risk estimate, but the 95% confidence interval included the null value. Motorcycle helmets were associated with a 69% reduction in skull fractures, 71% reduction in cerebral contusion, and 53% reduction in intracranial hemorrhage. This study finds that current motorcycle helmets do not protect equally against

  15. A Model for Protective Behavior against the Harmful Effects of Radiation based on Medical Institution Classifications

    International Nuclear Information System (INIS)

    Han, Eun Ok; Kwon, Deok Mun; Dong, Kyung Rae; Han, Seung Moo

    2010-01-01

    This study surveyed a total of 1,322 radiation technologist in health care institutions throughout Korea. This is a comparative study conducted on the levels of protective behavior against the harmful effects of radiation in heath care institutions which indicated that university hospitals and general hospitals showed higher level of protective behavior than for medical practitioners. This study found university hospitals have the following 7 characteristics to manage protective behavior against the harmful effects of radiation, protective environment, self-efficacy by distinction of task , self-efficacy, expectation of the protective behavior, the number of patients, level of the education related to the protection of the harmful effects of radiation and protective attitude. While general hospitals have the following 3 characteristics protective environment, expectation of the protective behavior and protective attitude. Hospitals have the following 4 characteristics protective environment, expectation of the protective behavior, protective attitude and self-efficacy and medical clinics have characteristics protective environment

  16. A Model for Protective Behavior against the Harmful Effects of Radiation based on Medical Institution Classifications

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Ok; Kwon, Deok Mun [Daegu Health College, Daegu (Korea, Republic of); Dong, Kyung Rae [Gwangju Health College University, Gwangju (Korea, Republic of); Han, Seung Moo [Kyung Hee University, Seoul (Korea, Republic of)

    2010-12-15

    This study surveyed a total of 1,322 radiation technologist in health care institutions throughout Korea. This is a comparative study conducted on the levels of protective behavior against the harmful effects of radiation in heath care institutions which indicated that university hospitals and general hospitals showed higher level of protective behavior than for medical practitioners. This study found university hospitals have the following 7 characteristics to manage protective behavior against the harmful effects of radiation, protective environment, self-efficacy by distinction of task , self-efficacy, expectation of the protective behavior, the number of patients, level of the education related to the protection of the harmful effects of radiation and protective attitude. While general hospitals have the following 3 characteristics protective environment, expectation of the protective behavior and protective attitude. Hospitals have the following 4 characteristics protective environment, expectation of the protective behavior, protective attitude and self-efficacy and medical clinics have characteristics protective environment.

  17. The effect of crop protection strategy on pest and beneficials incidence in protected crops.

    Science.gov (United States)

    Lourenço, I; Rodrigues, S; Figueiredo, E; Godinho, M C; Marques, C; Amaro, F; Mexia, A

    2002-01-01

    This study took place in the Oeste region from 1996-1999 and it intended to analyse if the crop protection strategy followed by the farmer influenced the arthropod incidence and the natural control in protected vegetable crops under Mediterranean conditions. The observations were made fortnightly (Autumn/Winter) or weekly (Spring/Summer) in 30-60 plants/parcel (1 plant/35 m2) in order to evaluate incidences. Samples of pests and natural enemies were collected for systematic identification in two greenhouses for each protection strategy (traditional chemical control (TCC), integrated pest management (IPM) and pest control allowed in organic farming (OF)) in lettuce, tomato, green beans and cucumber. Data on incidence of mites, aphids, caterpillars, leafminers, whiteflies, thrips and respective natural enemies were registered as well as phytosanitary treatments performed (farmers' information and/or in loco traces). The leafminers were the pest whose incidence more often presented significant statistical differences between the studied protection strategies. In relation to this pest, the main results obtained were: a higher feeding punctures incidence in TCC than in IPM; higher incidence of adults, mines and feeding punctures in TCC than in OF; and a higher mines' incidence in IPM than in OF. Both in TCC and IPM high percentages of plants with mines were found although without an adult proportional presence. In the first case this was due to the repeatedly phytosanitary treatments applied; in the second case it was due to the natural control, since in IPM and OF greenhouses the collected larvae were mostly parasitized or dead. In spite of the fact these two strategies have as final result a similar mines and adults incidence, their production and environmental costs are quite different. Significant differences at the beneficials' population level between TCC greenhouses and IPM or OF greenhouses were found. As the farmers did no biological treatments these

  18. Radiation protection in the age of accountability - measuring our effectiveness

    International Nuclear Information System (INIS)

    Hutchinson, D.E.

    1993-01-01

    Effectiveness and accountability were catch-words of the 1980s for public and private enterprises. This mood has persisted into the current decade and radiation protection authorities have not escaped the organisational microscope. But whereas simple models and measures of effectiveness can be applied to most private companies and government agencies, organisations in the regulatory and preventative health areas cannot be assessed by the same criteria. These organisations are fundamentally different because their primary objective is one of minimisation. This paper looks at options for measuring and reporting the effectiveness of radiation protection organisations. Some performance indicators are proposed and evaluated. The intention is not, however, to present a 'solution' to this apparently vexing problem. Indeed, the answer may be that there is none. 11 refs., 4 figs

  19. Energy evaluation of protection effectiveness of anti-vibration gloves.

    Science.gov (United States)

    Hermann, Tomasz; Dobry, Marian Witalis

    2017-09-01

    This article describes an energy method of assessing protection effectiveness of anti-vibration gloves on the human dynamic structure. The study uses dynamic models of the human and the glove specified in Standard No. ISO 10068:2012. The physical models of human-tool systems were developed by combining human physical models with a power tool model. The combined human-tool models were then transformed into mathematical models from which energy models were finally derived. Comparative energy analysis was conducted in the domain of rms powers. The energy models of the human-tool systems were solved using numerical simulation implemented in the MATLAB/Simulink environment. The simulation procedure demonstrated the effectiveness of the anti-vibration glove as a method of protecting human operators of hand-held power tools against vibration. The desirable effect is achieved by lowering the flow of energy in the human-tool system when the anti-vibration glove is employed.

  20. Effectiveness of eye drops protective against ultraviolet radiation.

    Science.gov (United States)

    Daxer, A; Blumthaler, M; Schreder, J; Ettl, A

    1998-01-01

    To test the effectiveness of commercially available ultraviolet (UV)-protective eye drops (8-hydroxy-1-methylchinolinium methylsulphate) which are recommended for protection against both solar and artificial UV radiation. The spectral transmission in the wavelength range from 250 to 500 nm was investigated in 1-nm steps using a high-resolution double monochromator with holographic gratings of 2,400 lines/mm and a 1,000-watt halogen lamp as light source. The transmission spectrum was measured for different values of the layer thickness. The transmission of a liquid layer of about 10 microns, which corresponds to the thickness of the human tear film, shows a cut-off at 290 nm with a transmission of about 25-50% at shorter wavelengths. For wavelengths longer than 290 nm the transmission is higher than 90%. The threshold time ratio for keratitis formation with and without eye drops is above 0.93 considering solar radiation on the earth's surface and above 0.65 considering radiation from arc-welding, respectively. The transmission spectrum of the eye drops under realistic conditions does not show a protective effect against solar UV radiation. However, there exists reduction of UVC radiation in the spectral range typical of artificial UV sources such as arc-welding. We cannot recommend the application of these eye drops as an UV-protective aid against eye damage by solar UV radiation.

  1. Enhancement of the far-UV lethality in yeast Candida guilliermondii by near-UV post-irradiation

    International Nuclear Information System (INIS)

    Fraikin, G.Y.; Pospelov, M.E.; Rubin, L.B.

    1980-01-01

    In experiments with the non-photoreactivable yeast Candida guilliermondii, radiations at 313, 334 and 365 nm, having no effect on untreated cell populations, produced an 'enhancing' effect on the lethality of 254 nm-pretreated cells. Wavelengths in the visible region of the spectrum did not exhibit a similar effect. (author)

  2. Effect of Remote Back-Up Protection System Failure on the Optimum Routine Test Time Interval of Power System Protection

    Directory of Open Access Journals (Sweden)

    Y Damchi

    2013-12-01

    Full Text Available Appropriate operation of protection system is one of the effective factors to have a desirable reliability in power systems, which vitally needs routine test of protection system. Precise determination of optimum routine test time interval (ORTTI plays a vital role in predicting the maintenance costs of protection system. In the most previous studies, ORTTI has been determined while remote back-up protection system was considered fully reliable. This assumption is not exactly correct since remote back-up protection system may operate incorrectly or fail to operate, the same as the primary protection system. Therefore, in order to determine the ORTTI, an extended Markov model is proposed in this paper considering failure probability for remote back-up protection system. In the proposed Markov model of the protection systems, monitoring facility is taken into account. Moreover, it is assumed that the primary and back-up protection systems are maintained simultaneously. Results show that the effect of remote back-up protection system failures on the reliability indices and optimum routine test intervals of protection system is considerable.

  3. Variation in the Protective Effect of Higher Education Against Depression*

    Science.gov (United States)

    Bauldry, Shawn

    2016-01-01

    Numerous studies document that higher education is associated with a reduced likelihood of depression. The protective effects of higher education, however, are known to vary across population subgroups. This study tests competing theories for who is likely to obtain a greater protective benefit from a college degree against depression through an analysis of data from the National Longitudinal Study of Adolescent Health and recently developed methods for analyzing heterogeneous treatment effects involving the use of propensity scores. The analysis examines how the effects of two “treatments” (at least some college education and attaining at least a four-year college degree) on latent depressive symptomology vary by background disadvantage, as indicated by having a low propensity for completing some college or attaining a four-year college degree. Results indicate that people from disadvantaged backgrounds realize a greater protective effect of higher education, either completing some college or attaining a four-year degree, against depressive symptomology than people from advantaged backgrounds. This pattern is more pronounced for people who attain at least a four-year degree than for people who complete at least some college education. PMID:27840772

  4. Combined action of taurine and cations of certain metals on post-irradiation survival of SOC cell culture

    International Nuclear Information System (INIS)

    Yartsev, E.I.; Aldonyasov, V.I.; Yakovlev, V.G.

    1975-01-01

    Effects of combined application of taurine and metals (potassium, magnesium, calcium and zinc) on the cell level have been studied. It has been found that various concentrations of taurine and potassium and zinc salts increase the survival of irradiated SOC cells up to 40% while addition of magnesium and calcium salts does not affect the taurine effectiveness. The highest effectiveness is obtained when potassium and taurine are added in equimolar amounts to the incubation medium

  5. Effective Hamiltonian for protected edge states in graphene

    International Nuclear Information System (INIS)

    Winkler, R.; Deshpande, H.

    2017-01-01

    Edge states in topological insulators (TIs) disperse symmetrically about one of the time-reversal invariant momenta Λ in the Brillouin zone (BZ) with protected degeneracies at Λ. Commonly TIs are distinguished from trivial insulators by the values of one or multiple topological invariants that require an analysis of the bulk band structure across the BZ. We propose an effective two-band Hamiltonian for the electronic states in graphene based on a Taylor expansion of the tight-binding Hamiltonian about the time-reversal invariant M point at the edge of the BZ. This Hamiltonian provides a faithful description of the protected edge states for both zigzag and armchair ribbons, though the concept of a BZ is not part of such an effective model. In conclusion, we show that the edge states are determined by a band inversion in both reciprocal and real space, which allows one to select Λ for the edge states without affecting the bulk spectrum.

  6. An Effective Method for Protecting the Integrity of Mobile Agent

    OpenAIRE

    YARAHMADI, H.; KAMANKESH, M.

    2015-01-01

    Abstract. A mobile agent is software which performs an action autonomously and independently as a person or organizations assistance. Mobile agents are used for searching information, retrieval information, filtering, intruder recognition in networks, and so on. One of the important issues of mobile agent is their security. It must consider different security issues in effective and secured usage of mobile agent. One of those issues is the integrity’s protection of mobile agents.In this paper...

  7. Protective effect of corticosteroids on radiation pneumonitis in mice

    International Nuclear Information System (INIS)

    Gross, N.J.; Narine, K.R.; Wade, R.

    1988-01-01

    We explored the protective effect of corticosteroids on the mortality of mice that received thoracic irradiation. Methylprednisolone, 100 mg/kg/week, given from 11 weeks after gamma irradiation of the thorax resulted in an increase in the LD50 (11-26 weeks) from 14.3 +/- 0.3 (mean +/- SE) Gy to 17.6 +/- 0.4 Gy, P less than 0.001, a protection factor of 1.2. Withdrawal of steroids at various times during the period of radiation pneumonitis resulted in accelerated mortality in the next 2-4 weeks, so that the cumulative mortality caught up with that of control animals by 4 weeks after steroid withdrawal. However, after the end of the usual period of pneumonitis withdrawal of steroids did not result in accelerated mortality, suggesting that the time when steroids are protective corresponds to the duration of pneumonitis. A smaller dose of steroids, 25 mg/kg/week, was found to be as protective as the larger dose used in the above experiments. The possibility that corticosteroids reduce mortality, even when given many weeks after radiation, may have important practical and theoretical implications

  8. Protecting the fast breeders: Problem formulation and effects analysis

    International Nuclear Information System (INIS)

    Oughton, D.H.

    2003-01-01

    Recent debates on protection of the environment from ionising radiation have reached reasonable agreement over the ethical and philosophical basis of environmental protection and a recognition that a practical system of protection will need to support (at a minimum) the principles of sustainable development, biodiversity, and conservation. However, there is still some controversy over the use of dose assessment tools within risk evaluation and management. The paper uses the case of the Dounreay 'radioactive rabbits' to discuss the advantages and limitations of proposed systems, focusing primarily on the interaction between ecological risk assessment (ERA) and the reference flora and fauna approach. It concludes that the reference approach is a valuable tool for the analysis of environmental effects, but that there is a problem if it becomes the driving force of the protection framework. In particular, there is a need for a clearer focus on non-technical issues within the problem formulation stage of ERA, particularly the social, ethical, political and economic issues, and there should be a strong commitment to stakeholder involvement at this stage. The problem formulation stage should identify the relevant assessment tools; the assessment tool should dictate neither the problem formulation nor the risk management. (author)

  9. Protective Effect of HSP25 on Radiation Induced Tissue Damage

    International Nuclear Information System (INIS)

    Lee, Hae-June; Lee, Yoon-Jin; Kwon, Hee-Choong; Bae, Sang-Woo; Lee, Yun-Sil; Kim, Sung Ho

    2007-01-01

    Control of cancer by irradiation therapy alone or in conjunction with combination chemotherapy is often limited by organ specific toxicity. Ionizing irradiation toxicity is initiated by damage to normal tissue near the tumor target and within the transit volume of radiotherapy beams. Irradiation-induced cellular, tissue, and organ damage is mediated by acute effects, which can be dose limiting. A latent period follows recovery from the acute reaction, then chronic irradiation fibrosis (late effects) pose a second cause of organ failure. HSP25/27 has been suggested to protect cells against apoptotic cell death triggered by hyperthermia, ionizing radiation, oxidative stress, Fas ligand, and cytotoxic drugs. And several mechanisms have been proposed to account for HSP27-mediated apoptotic protection. However radioprotective effect of HSP25/27 in vivo system has not yet been evaluated. The aim of this study was to evaluate the potential of exogenous HSP25 expression, as delivered by adenoviral vectors, to protect animal from radiation induced tissue damage

  10. Protective Effects of Cilastatin against Vancomycin-Induced Nephrotoxicity

    Directory of Open Access Journals (Sweden)

    Blanca Humanes

    2015-01-01

    Full Text Available Vancomycin is a very effective antibiotic for treatment of severe infections. However, its use in clinical practice is limited by nephrotoxicity. Cilastatin is a dehydropeptidase I inhibitor that acts on the brush border membrane of the proximal tubule to prevent accumulation of imipenem and toxicity. The aim of this study was to investigate the potential protective effect of cilastatin on vancomycin-induced apoptosis and toxicity in cultured renal proximal tubular epithelial cells (RPTECs. Porcine RPTECs were cultured in the presence of vancomycin with and without cilastatin. Vancomycin induced dose-dependent apoptosis in cultured RPTECs, with DNA fragmentation, cell detachment, and a significant decrease in mitochondrial activity. Cilastatin prevented apoptotic events and diminished the antiproliferative effect and severe morphological changes induced by vancomycin. Cilastatin also improved the long-term recovery and survival of RPTECs exposed to vancomycin and partially attenuated vancomycin uptake by RPTECs. On the other hand, cilastatin had no effects on vancomycin-induced necrosis or the bactericidal effect of the antibiotic. This study indicates that cilastatin protects against vancomycin-induced proximal tubule apoptosis and increases cell viability, without compromising the antimicrobial effect of vancomycin. The beneficial effect could be attributed, at least in part, to decreased accumulation of vancomycin in RPTECs.

  11. Studies on sister chromatid exchange (SCE) induction by γ-irradiation and protective effect of L-cysteine in HeLa cells

    International Nuclear Information System (INIS)

    Shah, V.C.; Mittal, S.C.

    1987-01-01

    Effect of different doses of γ-irradiation on SCE induction in unifiliarly 5-bromo 2-deoxyuridine substituted DNA was studied in various phases of cell cycle. Changes in γ-irradiation induced SCE frequency was measured by post-irradiation treatment with antimutagen L-cysteine. Perturbation in cellular proliferation kinetics due to γ-irradiation and γ-irradiation plus L-cysteine was also studied. It was observed that γ-irradiation is an efficient inducer of SCE and is most effective in S phase. L-cysteine also causes SCE induction which is slightly higher than the spontaneous level of SCEs found in HeLa cells. However, post-irradiation addition of L-cysteine reduces SCE frequency in γ-irradiated cultures and this reduction is maximum in G 1 phase irradiated cells. γ-irradiation delayed the mitosis considerably and this delay continued to increase with increasing doses. L-cysteine reduced the delay in cell cycle caused by γ-irradiation. (orig.) [de

  12. Does cannabidiol protect against adverse psychological effects of THC?

    Directory of Open Access Journals (Sweden)

    Raymond J.M. eNiesink

    2013-10-01

    Full Text Available The recreational use of cannabis can have persistent adverse effects on mental health. Delta-9-tetrahydrocannabinol (THC is the main psychoactive constituent of cannabis, and most, if not all, of the effects associated with the use of cannabis are caused by THC. Recent studies have suggested a possible protective effect of another cannabinoid, cannabidiol (CBD. A literature search was performed in the bibliographic databases PubMed, PsycINFO and Web of Science using the keyword ‘cannabidiol.’ After removing duplicate entries, 1295 unique titles remained. Based on the titles and abstracts, an initial selection was made. The reference lists of the publications identified in this manner were examined for additional references. Cannabis is not a safe drug. Depending on how often someone uses, the age of onset, the potency of the cannabis that is used and someone's individual sensitivity, the recreational use of cannabis may cause permanent psychological disorders. Most recreational users will never be faced with such persistent mental illness, but in some individuals cannabis use leads to undesirable effects: cognitive impairment, anxiety, paranoia and increased risks of developing chronic psychosis or drug addiction. Studies examining the protective effects of CBD have shown that CBD can counteract the negative effects of THC. However, the question remains of how the laboratory results translate to the types of cannabis that are encountered by real-world recreational users.

  13. Composite symmetry-protected topological order and effective models

    Science.gov (United States)

    Nietner, A.; Krumnow, C.; Bergholtz, E. J.; Eisert, J.

    2017-12-01

    Strongly correlated quantum many-body systems at low dimension exhibit a wealth of phenomena, ranging from features of geometric frustration to signatures of symmetry-protected topological order. In suitable descriptions of such systems, it can be helpful to resort to effective models, which focus on the essential degrees of freedom of the given model. In this work, we analyze how to determine the validity of an effective model by demanding it to be in the same phase as the original model. We focus our study on one-dimensional spin-1 /2 systems and explain how nontrivial symmetry-protected topologically ordered (SPT) phases of an effective spin-1 model can arise depending on the couplings in the original Hamiltonian. In this analysis, tensor network methods feature in two ways: on the one hand, we make use of recent techniques for the classification of SPT phases using matrix product states in order to identify the phases in the effective model with those in the underlying physical system, employing Künneth's theorem for cohomology. As an intuitive paradigmatic model we exemplify the developed methodology by investigating the bilayered Δ chain. For strong ferromagnetic interlayer couplings, we find the system to transit into exactly the same phase as an effective spin-1 model. However, for weak but finite coupling strength, we identify a symmetry broken phase differing from this effective spin-1 description. On the other hand, we underpin our argument with a numerical analysis making use of matrix product states.

  14. The usage of phase change materials in fire fighter protective clothing: its effect on thermal protection

    Science.gov (United States)

    Zhao, Mengmeng

    2017-12-01

    The thermal protective performance of the fire fighter protective clothing is of vital importance for fire fighters. In the study fabrics treated by phase change materials (PCMs) were applied in the multi-layered fabrics of the fire fighter protective clothing ensemble. The PCM fabrics were placed at the different layers of the clothing and their thermal protective performance were measured by a TPP tester. Results show that with the application of the PCM fabrics the thermal protection of the multi-layered fabrics was greatly increased. The time to reach a second degree burn was largely reduced. The location of the PCM fabrics at the different layers did not affect much on the thermal protective performance. The higher amount of the PCM adds on, the higher thermal protection was brought. The fabrics with PCMs of a higher melting temperature could contribute to higher thermal protection.

  15. Training for effective environmental protection in the nuclear industry

    International Nuclear Information System (INIS)

    Parkinson, D.; Brake, J.; Hickman, C.; Tamm, J.

    2007-01-01

    This paper examines the role of environmental training in the delivery of effective environmental protection programs for construction projects in the nuclear industry. The paper uses a case study approach, based on Point Lepreau Generating Station's Refurbishment Project, to demonstrate how the underpinning principles of 'training, awareness and competence' can be delivered within a structured environmental management framework, to achieve sustained excellence in environmental management and performance. Key issues addressed by the paper include the early identification of different target audiences, making effective use of communication themes, and the importance of reinforcement and follow-up in support of training goals. (author)

  16. UV dose-effect relationships and current protection exposure standards

    International Nuclear Information System (INIS)

    Singh, M.S.; Campbell, G.W.

    1982-04-01

    In this paper we have attempted to quantify the health effects in man of uv-radiation exposure of wavelengths from 240 nm to 320 nm. Exposure to uv in this region could result in the formation of skin cancer or premature aging in man. The induction of cancer by uv radiation results from changes in genetic material. We have used the DNA action spectrum coupled with the uv skin cancer data available in the literature to derive the dose-effect relationships. The results are compared against the current uv protection standards

  17. Post irradiation examination and analysis of 13(U,Pu) C-fuel pins irradiated in the thermal flux of FR 2

    International Nuclear Information System (INIS)

    Weimar, P.; Steiner, H.

    1979-01-01

    The post-irradiation examination of the pins at Karlsruhe Hot Cells revealed the following results: Nearly all specimens showed noteworthy clad deformations (up to 3%). Defects in the form of cracks in the clad were found at three pins. The observed clad deformations resulted from mechanical interaction between fuel and cladding in consequence of an inexorable fuel swelling. A linear relationship between burnup and clad deformation was found. Defects were observed for burnups greater than 50 MWd/kgM and can be explained by the small fabrications clearances between clad and fuel pellets (50-90 μm) and high smear densities. Fission gas measurements were performed in a three fold way, gas release, gas trapped in pores and gas in solid solution in the lattice of the mixed carbide were determined. The gas release fraction showed values between 10 and 15%. Whereas the fission gas content trapped in large pores (> 1 μm) was linearly dependent on burnup, fission gas in small pores and in solid solution reached a saturation value at about 20 MWd/kgM. Measurements of micro-hardness revealed carburization depths of the clad of up to 40% at temperatures of about 650 0 C. Furtermore, it could be confirmed that the carburization depth followed an Arrhenius law. (orig.)

  18. Investigation on cause of outage of Wide Range Monitor (WRM) in High Temperature engineering Test Reactor (HTTR). Post Irradiation Examination (PIE) toward investigation of the cause

    International Nuclear Information System (INIS)

    Shinohara, Masanori; Saito, Kenji; Takada, Shoji; Ishimi, Akihiro; Katsuyama, Kozo; Motegi, Toshihiro

    2012-08-01

    An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the past developed life is one of the issues to develop the technology basis of High Temperature Gas cooled Reactor (HTGR). Then, two experimental investigations were carried out to reveal the cause of the outage by specifying the damaged part causing the event in the WRM. The one is a post irradiation examination using the X-ray computed tomography scanner in Fuels Monitoring Facility (FMF) to specify the damaged part in the WRM. The other is an experiment using a mock-up simulating the WRM fabricated by the fabricator. The characteristic impedance of the damaged WRM was measured by Time Domain Reflectometry, which was compared with that of the mock-up, which could narrow down the damaged part in the WRM. This report summarized the results of the PIE and the experimental investigation using the mock-up to reveal the cause of outage of WRM. (author)

  19. Post-irradiation examination of prototype Al-64 wt% U{sub 3}Si{sub 2} fuel rods from NRU

    Energy Technology Data Exchange (ETDEWEB)

    Sears, D.F.; Primeau, M.F.; Buchanan, C.; Rose, D. [Chalk River Labs., Ontario (Canada)

    1997-08-01

    Three prototype fuel rods containing Al-64 wt% U{sub 3}Si{sub 2} (3.15 gU/cm{sup 3}) have been irradiated to their design burnup in the NRU reactor without incident. The fuel was fabricated using production-scale equipment and processes previously developed for Al-U{sub 3}Si fuel fabrication at Chalk River Laboratories, and special equipment developed for U{sub 3}Si{sub 2} powder production and handling. The rods were irradiated in NRU up to 87 at% U-235 burnup under typical driver fuel conditions; i.e., nominal coolant inlet temperature 37{degrees}C, inlet pressure 654 kPa, mass flow 12.4 L/s, and element linear power ratings up to 73 kW/m. Post-irradiation examinations showed that the fuel elements survived the irradiation without defects. Fuel core diametral increases and volumetric swelling were significantly lower than that of Al-61 wt% U{sub 3}Si fuel irradiated under similar conditions. This irradiation demonstrated that the fabrication techniques are adequate for full-scale fuel manufacture, and qualified the fuel for use in AECL`s research reactors.

  20. Some results on development, irradiation and post-irradiation examinations of fuels for fast reactor-actinide burner (MOX and inert matrix fuel)

    International Nuclear Information System (INIS)

    Poplavsky, V.; Zabudko, L.; Moseev, L.; Rogozkin, B.; Kurina, I.

    1996-01-01

    Studies performed have shown principal feasibility of the BN-600 and BN-800 cores to achieve high efficiency of Pu burning when MOX fuel with Pu content up to 45% is used. Valuable experience on irradiation behaviour of oxide fuel with high Pu content (100%) was gained as a result of operation of two BR-10 core loadings where the maximum burnup 14 at.% was reached. Post-irradiation examination (PIE) allowed to reveal some specific features of the fuel with high plutonium content. Principal irradiation and PIE results are presented in the paper. Use of new fuel without U-238 provides the maximum burning capability as in this case the conversion ratio is reduced to zero. Technological investigations of inert matrix fuels have been continued now. Zirconium carbide, zirconium nitride, magnesium oxide and other matrix materials are under consideration. Inert matrices selection criteria are discussed in the paper. Results of technological study, of irradiation in the BOR-60 reactor and PIE results of some inert matrix fuels are summarized in this report. (author). 2 refs, 1 fig., 3 tabs

  1. Post-irradiation examinations and theoretical analyses of the fuel and fuel pin behavior of innovative systems

    International Nuclear Information System (INIS)

    Ernst, W.; Freund, D.; Geithoff, D.; Heck, M.; Jacobi, O.; Steiner, H.; Weimar, P.

    1995-01-01

    For the development of LMR cladding materials an irradiation test was performed in the KNK II reactor between 1986 and 1991. It demonstrated that a temperature gradient in the cladding has no observable effect on swelling behavior. PIEs of transient experiments in the Petten HFR have shown no significant cladding deformations. (orig.)

  2. Breast Milk Hormones and Their Protective Effect on Obesity

    Directory of Open Access Journals (Sweden)

    Fissore MariaF

    2009-11-01

    Full Text Available Data accumulated over recent years have significantly advanced our understanding of growth factors, cytokines, and hormones in breast milk. Here we deal with leptin, adiponectin, IGF-I, ghrelin, and the more recently discovered hormones, obestatin, and resistin, which are present in breast milk and involved in food intake regulation and energy balance. Little is known about these compounds in infant milk formulas. Nutrition in infancy has been implicated in the long-term tendency to obesity, and a longer duration of breastfeeding appears to protect against its development. Diet-related differences in serum leptin and ghrelin values in infancy might explain anthropometric differences and differences in dietary habits between breast-fed and formula-fed infants also later in life. However, there are still gaps in our understanding of how hormones present in breast milk affect children. Here we examine the data related to hormones contained in mother's milk and their potential protective effect on subsequent obesity.

  3. Psidium guajava Linn confers gastro protective effects on rats.

    Science.gov (United States)

    Livingston Raja, N R; Sundar, K

    2012-02-01

    The best alternatives to synthetic medicines, available, for the treatment of gastric ulcer disorders, are the natural products found in plants. They are known to exhibit a variety of activities. The present study is aimed at the screening of Psidium (P.) guajava Linn for its gastro protective effect. The methanol extracts of the leaves of P. guajava were tested in three different ulcer models viz. aspirin (ASP), pyloric ligation (PL) and ethanol (EtoH) induced ulcer models in rats. The treatment of P. guajava at varying doses (100 mg/kg and 200 mg/kg) significantly (p guajava may be responsible for the anti-ulcer property exhibited. The results further suggest that P. guajava possess gastro protective as well as ulcer healing properties which might also be due to its anti-secretory properties.

  4. Effectiveness of Human Research Protection Program Performance Measurements.

    Science.gov (United States)

    Tsan, Min-Fu; Nguyen, Yen

    2017-10-01

    We analyzed human research protection program performance metric data of all Department of Veterans Affairs research facilities obtained from 2010 to 2016. Among a total of 25 performance metrics, 21 (84%) showed improvement, four (16%) remained unchanged, and none deteriorated during the study period. The overall improvement from these 21 performance metrics was 81.1% ± 18.7% (mean ± SD), with a range of 30% to 100%. The four performance metrics that did not show improvement all had initial noncompliance/incidence rates of performance metrics that showed improvement ranged from 0.05% to 60%. However, of the 21 performance metrics that showed improvement, 10 had initial noncompliance/incidence rates of performance measurement is an effective tool in improving the performance of human research protection programs.

  5. Protected area effectiveness against land development in Spain.

    Science.gov (United States)

    Rodríguez-Rodríguez, David; Martínez-Vega, Javier

    2018-06-01

    Land use-land cover (LULC) changes towards artificial covers are one of the main global threats to biodiversity conservation. In this comprehensive study, we tested a number of methodological and research hypotheses, and a new covariate control technique in order to address common protected area (PA) assessment issues and accurately assess whether different PA networks have had an effect at preventing development of artificial LULCs in Spain, a highly biodiverse country that has experienced massive socioeconomic transformations in the past two decades. We used digital census data for four PA networks designated between 1990 and 2000: Nature Reserves (NRs), Nature Parks (NPs), Sites of Community Importance (SCIs) and Special Protection Areas (SPAs). We analysed the effect of explanatory variables on the ecological effectiveness of protected polygons (PPs): Legislation stringency, cummulative legal designations, management, size, age and bio-physical characteristics. A multiple Before-After-Control-Impact (BACI) semi-experimental research design was used whereby artificial land cover increase (ALCI) and proportional artificial land cover increase (PALCI) results were compared inside and outside PAs, using 1 km and 5 km buffer areas surrounding PAs as controls. LULC data were retrieved from Corine Land Cover (CLC) 1990 and 2006 data. Results from three spatial-statistical models using progressively restrictive criteria to select control areas increasingly more accurate and similar to the assessed PPs were compared. PAs were a generally effective territorial policy to prevent land development in Spain. NRs were the most effective PA category, with no new artificial land covers in the assessed period, although exact causality could not be attributed due to legal overlaps. SPAs were the least effective category, with worse ALCI data than their control areas. Legal protection was effective against land development, which was influenced by most bio-physical variables

  6. The protective effect of ischemic preconditioning on rat testis

    Directory of Open Access Journals (Sweden)

    Ciralik Harun

    2007-12-01

    Full Text Available Abstract Background It has been demonstrated that brief episodes of sublethal ischemia-reperfusion, so-called ischemic preconditioning, provide powerful tissue protection in different tissues such as heart, brain, skeletal muscle, lung, liver, intestine, kidney, retina, and endothelial cells. Although a recent study has claimed that there are no protective effects of ischemic preconditioning in rat testis, the protective effects of ischemic preconditioning on testicular tissue have not been investigated adequately. The present study was thus planned to investigate whether ischemic preconditioning has a protective effect on testicular tissue. Methods Rats were divided into seven groups that each contained seven rats. In group 1 (control group, only unilateral testicular ischemia was performed by creating a testicular torsion by a 720 degree clockwise rotation for 180 min. In group 2, group 3, group 4, group 5, group 6, and group 7, unilateral testicular ischemia was performed for 180 min following different periods of ischemic preconditioning. The ischemic preconditioning periods were as follows: 10 minutes of ischemia with 10 minutes of reperfusion in group 2; 20 minutes of ischemia with 10 minutes of reperfusion in group 3; 30 minutes of ischemia with 10 minutes of reperfusion in group 4; multiple preconditioning periods were used (3 × 10 min early phase transient ischemia with 10 min reperfusion in all episodes in group 5; multiple preconditioning periods were used (5, 10, and 15 min early phase transient ischemia with 10 min reperfusion in all episodes in group 6; and, multiple preconditioning periods were used (10, 20, and 30 min early phase transient ischemia with 10 min reperfusion in all episodes in group 7. After the ischemic protocols were carried out, animals were sacrificed by cervical dislocation and testicular tissue samples were taken for biochemical measurements (protein, malondialdehyde, nitric oxide and histological examination

  7. Bioavailability, metabolism and potential health protective effects of dietary flavonoids

    DEFF Research Database (Denmark)

    Bredsdorff, Lea

    Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several epidemiologi......Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several...... of their content. In addition, variation in individual metabolic genotype and microflora may greatly affect the actual flavonoid exposure. The preventive effects of flavonoids on CHD are mainly ascribed to their anti-inflammatory and antioxidant activities. Several mechanisms of anti-inflammatory and antioxidant...... effective absorption of hesperetin and naringenin from the small intestine when consumed as glucosides compared to absorption in the colon VII after microbial degradation of the rhamnoglucosides. In addition it was shown that the conjugate profile was neither affected by the absorption site nor by a 3-fold...

  8. Protective Effect of ECQ on Rat Reflux Esophagitis Model.

    Science.gov (United States)

    Jang, Hyeon-Soon; Han, Jeong Hoon; Jeong, Jun Yeong; Sohn, Uy Dong

    2012-12-01

    This study was designed to determine the protective effect of Rumex Aquaticus Herba extracts containing quercetin-3-β-D-glucuronopyranoside (ECQ) on experimental reflux esophagitis. Reflux esophagitis was induced by surgical procedure. The rats were divided into seven groups, namely normal group, control group, ECQ (1, 3, 10, 30 mg/kg) group and omeprazole (30 mg/kg) group. ECQ and omeprazole groups received intraduodenal administration. The Rats were starved for 24 hours before the experiments, but were freely allowed to drink water. ECQ group attenuated the gross esophagitis significantly compared to that treated with omeprazole in a dose-dependent manner. ECQ decreased the volume of gastric juice and increased the gastric pH, which are similar to those of omeprazole group. In addition, ECQ inhibited the acid output effectively in reflux esophagitis. Significantly increased amounts of malondialdehyde (MDA), myeloperoxidase (MPO) activity and the mucosal depletion of reduced glutathione (GSH) were observed in the reflux esophagitis. ECQ administration attenuated the decrement of the GSH levels and affected the MDA levels and MPO activity. These results suggest that the ECQ has a protective effect which may be attributed to its multiple effects including anti-secretory, anti-oxidative and anti-inflammatory actions on reflux esophagitis in rats.

  9. Protective gloves on manual sugar cane cutting are really effective?

    Science.gov (United States)

    Abrahão, R F; Gonzaga, M C; Braunbeck, O A

    2012-01-01

    Problems related to the use of personal protective equipment (PPE), specially the use of protective gloves for the manual sugar cane cutting, motivated this research, made possible by a tripartite negotiation involving the Ministry of Labor, the Union of Rural Workers and the Employer's Association of sugarcane agribusiness. The main objective was to evaluate, from an ergonomics perspective, the impact of use of the gloves during the manual cane sugar cutting, raising questions on safety, effectiveness and comfort. The research was carried in a sugarcane industry of São Paulo for two seasons involving 47 workers who made a qualitative analysis of acceptance of four models of protective gloves. The methodology included the use of semi-structured interviews, questionnaires and field observations and the experimental determination of the coefficient of static friction developed between the gloves and the surfaces of the machete handle. The main results indicate the general inadequacy of the gloves currently used forcing the employees to improvise. Workers found the glove of leather and nylon scraping the best reported for comfort in use. The overall results highlight the problem of detachment of test standards for the manufacture of PPE, ignoring users and the activity to be performed.

  10. Research on effectiveness assessment programs for physical protection system

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Janghoon; Yoo, Hosik; Ham, Taekyu [Korea Institute of Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of)

    2015-05-15

    PPS (Physical Protection System) is an integrated set of procedures, installation and human resources to protect valuable assets from physical attack of potential adversaries. Since nuclear facilities or radioactive materials can be attractive targets for terrorists, PPS should be installed and maintained throughout the entire lifecycle of nuclear energy systems. One of key ingredients for effective protection is a reliable assessment procedure of the PPS capability. Due to complexity of possible threat categories and pathways, several pathway analysis programs have been developed to ease analysis or visualization. ASSESS using ASD approach runs fast and adopts a relatively simple modeling process for facility elements. But uncertainty due to assumptions used in modeling might complicate the interpretation of results. On the other hand, 2D pathway program such as TESS can utilize more self-consistent detection probability and delay time since actual pathway on 2D map is available. Also, this pathway visualization helps users understand analysis result more intuitively. But, in general, 2D pathway programs require strong computational power and careful optimization. Another possible difference between two approaches is response force deployment and RFT.

  11. Protective effects of incensole acetate on cerebral ischemic injury.

    Science.gov (United States)

    Moussaieff, Arieh; Yu, Jin; Zhu, Hong; Gattoni-Celli, Sebastiano; Shohami, Esther; Kindy, Mark S

    2012-03-14

    The resin of Boswellia species is a major anti-inflammatory agent that has been used for centuries to treat various conditions including injuries and inflammatory conditions. Incensole acetate (IA), a major constituent of this resin, has been shown to inhibit NF-κB activation and concomitant inflammation, as well as the neurological deficit following head trauma. Here, we show that IA protects against ischemic neuronal damage and reperfusion injury in mice, attenuating the inflammatory nature of ischemic damage. IA given post-ischemia, reduced infarct volumes and improved neurological activities in the mouse model of ischemic injury in a dose dependent fashion. The protection from damage was accompanied by inhibition of TNF-α, IL-1β and TGF-β expression, as well as NF-κB activation following injury. In addition, IA is shown to have a therapeutic window of treatment up to 6h after ischemic injury. Finally, the protective effects of IA were partially mediated by TRPV3 channels as determined by the TRPV3 deficient mice and channel blocker studies. This study suggests that the anti-inflammatory and neuroprotective activities of IA may serve as a novel therapeutic treatment for ischemic and reperfusion injury, and as a tool in the ongoing research of mechanisms for neurological damage. Published by Elsevier B.V.

  12. Research on effectiveness assessment programs for physical protection system

    International Nuclear Information System (INIS)

    Seo, Janghoon; Yoo, Hosik; Ham, Taekyu

    2015-01-01

    PPS (Physical Protection System) is an integrated set of procedures, installation and human resources to protect valuable assets from physical attack of potential adversaries. Since nuclear facilities or radioactive materials can be attractive targets for terrorists, PPS should be installed and maintained throughout the entire lifecycle of nuclear energy systems. One of key ingredients for effective protection is a reliable assessment procedure of the PPS capability. Due to complexity of possible threat categories and pathways, several pathway analysis programs have been developed to ease analysis or visualization. ASSESS using ASD approach runs fast and adopts a relatively simple modeling process for facility elements. But uncertainty due to assumptions used in modeling might complicate the interpretation of results. On the other hand, 2D pathway program such as TESS can utilize more self-consistent detection probability and delay time since actual pathway on 2D map is available. Also, this pathway visualization helps users understand analysis result more intuitively. But, in general, 2D pathway programs require strong computational power and careful optimization. Another possible difference between two approaches is response force deployment and RFT

  13. DECOMMISSIONING OF SHIELDED FACILITIES AT WINFRITH USED FOR POST IRRADIATION EXAMINATION OF NUCLEAR FUELS and OTHER ACTIVE ITEMS

    International Nuclear Information System (INIS)

    Miller, K.D.; Parkinson, S.J.; Cornell, R.M.; Staples, A.T.

    2003-01-01

    This paper describes the approaches used in the clearing, cleaning, decontamination and decommissioning of a very large suite of seven concrete shielded caves and other facilities used by UKAEA at Winfrith Technology Centre, England over a period of about 30 years for the postirradiation examination (PIE) of a wide range of nuclear fuels and other very active components. The basic construction of the facilities will first be described, setting the scene for the major challenges that 1970s' thinking posed for decommissioning engineers. The tendency then to use large and heavy items of equipment supported upon massive steel bench structures produced a series of major problems that had to be overcome. The means of solving these problems by utilization of relatively simple and inexpensive equipment will be described. Later, a further set of challenges was experienced to decontaminate the interior surfaces to allow man entries to be undertaken at acceptable dose rates. The paper will describe the types of tooling used and the range of complementary techniques that were employed to steadily reduce the dose rates down to acceptable levels. Some explanations will also be given for the creation of realistic dose budgets and the methods of recording and continuously assessing the progress against these budgets throughout the project. Some final considerations are given to the commercial approaches to be adopted throughout this major project by the decommissioning engineers. Particular emphasis will be given to the selection of equipment and techniques that are effective so that the whole process can be carried out in a cost-effective and timely manner. The paper also provides brief complementary information obtained during the decommissioning of a plutonium-contaminated facility used for a range of semi-experimental purposes in the late 1970s. The main objective here was to remove the alpha contamination in such a manner that the volume of Plutonium Contaminated Materials (P

  14. Influence of helium embrittlement on post-irradiation creep rupture behaviour of austenitic and martensitic stainless steels

    International Nuclear Information System (INIS)

    Wassilew, C.

    1982-01-01

    The author has investigated the influence of helium embrittlement on the creep rupture properties of the austenitic stainless steels 1.4970 and 1.4962 and the martensitic stainless steel 1.4914 after irradiation in the BR-2 reactor in Mol, Belgium. The results show that austenitic steels react much more strongly to the embrittlement effect of the helium than do martensitic steels. The causes of the lower embrittlement tendency of the martensitic than of both austenitic stainless steels were analysed carefully. A new embrittlement model was developed on the basis of data derived from the creep rupture experiments, and reinforced by a simple metallographic investigation of the fracture zone and its immediate environment. This model pays specific attention to the role of the twin planes as the most efficient area of increased vacancy production, and takes into account the ability of the twin boundaries to transport these vacancies with reduced energy and low loss into the high-angle grain boundaries. (author)

  15. Unique natural exopolysaccharides for biomimetic protective effect against urban pollution.

    Science.gov (United States)

    Borel, Magali; Lamarque, Elisabeth; Loing, Estelle

    Through natural selection, living organisms have evolved well-adapted survival strategies over time. The shallow salt waters of Moorea lagoon are the site of accumulation of microbial mats called "Kopara," in the native Polynesian language. This unique ecosystem is rich in film-forming exopolysaccharides (EPSs) secreted by microorganisms within the biofilm, as a mean to protect themselves from environmental stress (strong ultraviolet [UV], pH, salinity … ). Using blue biotechnology, a manufacturing process was developed to obtain an EPS with skin benefits. The active ingredient (EPS-229) protects against urban pollution, including free radicals, heavy metals, hydrocarbons, and PM 2.5 (particulate matter with a size lower than 2.5 μm). The anti-lipid peroxidation action of EPS-229 was studied in an in vitro UVB-irradiated keratinocyte culture model, using lipophilic fluorescent probe. The chelating properties of EPS-229 were evaluated in tubo in the presence of cadmium and lead. The protective effect of EPS-229 on pollution-exposed skin explants was investigated through quantification of released malondialdehyde (MDA) and histological observation of skin morphology using optical microscopy. Clinical evaluation of the protective and cleansing efficacy of a water solution containing EPS-229 (0.02% and 0.01% w/v, respectively) was performed, against placebo, on a panel of 18 volunteers. For these studies, the forearms of volunteers were treated with EPS-229 before (anti-adhesion affect) or after (cleansing effect) application of PM 2.5 (iron particles of 1 μm). The presence of skin-adherent particles was observed and quantified by image analysis, using specific digital masks. In vitro , EPS-229 significantly protected keratinocyte cell membranes from lipid peroxidation. A decrease of 28% was achieved when a concentration of 0.001% w/v EPS-229 was applied to the cell culture. In tubo , EPS-229 also presented strong chelating properties. Maximal adsorption was

  16. Protective effects of metformin on neointima formation in insulin resistance

    Directory of Open Access Journals (Sweden)

    Yu V Pankratova

    2013-06-01

    Full Text Available Реферат по материалам статьи Lu J, Ji J, Meng H, Wang D, Jiang B, Liu L, Randell E, Adeli K, Meng QH. The protective effect and underlying mechanism of metformin on neointima formation in fructose-induced insulin resistant rats. Cardiovasc Diabetol. 2013 Apr 5;12:58. doi: 10.1186/1475-2840-12-58.

  17. Post-irradiation examinations and high-temperature tests on undoped large-grain UO{sub 2} discs

    Energy Technology Data Exchange (ETDEWEB)

    Noirot, J., E-mail: jean.noirot@cea.fr [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Pontillon, Y. [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Yagnik, S. [EPRI, P.O. Box 10412, Palo Alto, CA 94303-0813 (United States); Turnbull, J.A. [Independent Consultant (United Kingdom)

    2015-07-15

    Within the Nuclear Fuel Industry Research (NFIR) programme, several fuel variants –in the form of thin circular discs – were irradiated in the Halden Boiling Water Reactor (HBWR) at burn-ups up to ∼100 GWd/t{sub HM}. The design of the fuel assembly was similar to that used in other HBWR programmes: the assembly contained several rods with fuel discs sandwiched between Mo discs, which limited temperature differences within each fuel disc. One such variant was made of large-grain UO{sub 2} discs (3D grain size = ∼45 μm) which were subjected to three burn-ups: 42, 72 and 96 GWd/t{sub HM}. Detailed characterizations of some of these irradiated large-grain UO{sub 2} discs were performed in the CEA Cadarache LECA-STAR hot laboratory. The techniques used included electron probe microanalysis (EPMA), scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS). Comparisons were then carried out with more standard grain size UO{sub 2} discs irradiated under the same conditions. Examination of the high burn-up large-grain UO{sub 2} discs revealed the limited formation of a high burn-up structure (HBS) when compared with the standard-grain UO{sub 2} discs at similar burn-up. High burn-up discs were submitted to temperature transients up to 1200 °C in the heating test device called Merarg at a relatively low temperature ramp rate (0.2 °C/s). In addition to the total gas release during these tests, the release peaks throughout the temperature ramp were monitored. Tests at 1600 °C were also conducted on the 42 GWd/t{sub HM} discs. The fuels were then characterized with the same microanalysis techniques as those used before the tests, to investigate the effects of these tests on the fuel’s microstructure and on the fission gas behaviour. This paper outlines the high resistance of this fuel to gas precipitation at high temperature and to HBS formation at high burn-up. It also shows the similarity of the positions, within the grains, where HBS forms

  18. Radiation protection and antitumor effects in Hatakeshimeji (Lyophyllum decastes sing)

    International Nuclear Information System (INIS)

    Ukawa, Yuuichi; Gu, Yeunhwa; Suzuki, Ikukatsu; Park, Sangrae; Hasegawa, Takeo; Tsukada, Sekihito; Terai, Kaoru; Tawaraya, Hitoshi

    2002-01-01

    The effect on an anti-tumor is admitted in the lyophyllum decastes sing extraction thing, and it has the action mechanism cleared to depend on the immunity action. The existence of the synergistic effect in effect on an anti-tumor radiation irradiation, an individual with the medication of lyophyllum decastes sing and effect on combination and the effect on protection of the leukocyte decrease by the radiation was examined by this research. After about 2x10 6 inoculated sarcoma 180 on the ICR mice, a lyophyllum decastes sing extraction thing gave 100mg/kg for 2 weeks in endoceliac at the every other day. After that, the radiation irradiation of 2 Gy was done three times, and it went to the sutra time target the number of the leukocytes, the lymph node ball some prizes of measurement. And, weight and tumor size were measured after the cancer cell inoculation two weeks. The decrease of the clear tumor size was recognized by the group that only a cancer cell was inoculated by the radiation independent irradiation group, lyophyllum decastes sing and the radiation combination group though tumor size increased as it passed. It faced by the group that only a cancer cell was inoculated after the irradiation 15 days though it died the precedent, and a half existed by lyophyllum decastes sing and the radiation combination group. And, the numbers of the leukocytes, the number of the lymphocyte were on the increase regardless of the existence of the radiation irradiation by the medication of lyophyllum decastes sing. It thinks with the thing that the effect is shown for the effect on immunity recovery in the radiotherapy and the prevention of a side effect of the radiation from this result. Showing the effect for not only effect on prevention of the cancer and effect on healing but also the effect on immunity recovery in the radiotherapy, the prevention of a side effect by taking lyophyllum decastes sing is considered

  19. Radiation-protective effect with screens of fluoroscopy

    International Nuclear Information System (INIS)

    Kitagawa, H.; Sasaki, Y.; Chaya, K.; Furui, Y.

    1991-01-01

    In a fluoroscopic situation supposing heartworm removal using flexible alligator forceps, the radiationprotective effect of lead-containing screens was examined. Regarding measurements using a gamma-survey meter, X-ray exposure to the operator was reduced from 24.6±7.5 micro-Sievert (μSv)/hr to 0.47±0.08μSv/hr by using protective screens at position A, which corresponds to the operator's face level. At position B, which corresponds to the position of operator's left-hand fingers, the exposure level decreased from 33.1±1.37μSv/hr to 3.01±1.23μSv/hr when screens were used, and decreased more to 0.44±0.16μSv/ hr with the use of protective gloves. At position C, which was at the operator's foot, the exposure level decreased from 0.65±0.27μSv/hr to 0.24±0.10μSv/hr. Regarding measurements using a film badge for 20 experimental dogs, in which each dog was fluoroscopied for 20 sec×15 times, the operator would be totally exposed to 0.1 mSv in H 3mm , dose equivalent value against the eye lens and H 70μm , dose equivalent value against the skin at position B, but below the minimal limit for detection of X-ray (0.1 mSv) in H 1cm , effective dose-equivalent value. Exposure levels were below the minimal limit at positions A and C and at all positions which were protected with screens. Also, dogs were exposed to X-ray 2.20±0.96 mSv on fluoroscopy for 20 sec x 15 times. (author)

  20. Effectiveness of China's National Forest Protection Program and nature reserves.

    Science.gov (United States)

    Ren, Guopeng; Young, Stephen S; Wang, Lin; Wang, Wei; Long, Yongcheng; Wu, Ruidong; Li, Junsheng; Zhu, Jianguo; Yu, Douglas W

    2015-10-01

    There is profound interest in knowing the degree to which China's institutions are capable of protecting its natural forests and biodiversity in the face of economic and political change. China's 2 most important forest-protection policies are its National Forest Protection Program (NFPP) and its national-level nature reserves (NNRs). The NFPP was implemented in 2000 in response to deforestation-caused flooding. We undertook the first national, quantitative assessment of the NFPP and NNRs to examine whether the NFPP achieved its deforestation-reduction target and whether the NNRs deter deforestation altogether. We used MODIS data to estimate forest cover and loss across mainland China (2000-2010). We also assembled the first-ever polygon dataset for China's forested NNRs (n = 237, 74,030 km(2) in 2000) and used both conventional and covariate-matching approaches to compare deforestation rates inside and outside NNRs (2000-2010). In 2000, 1.765 million km(2) or 18.7% of mainland China was forested (12.3% with canopy cover of ≥70%)) or woodland (6.4% with canopy cover <70% and tree plus shrub cover ≥40%). By 2010, 480,203 km(2) of forest and woodland had been lost, an annual deforestation rate of 2.7%. Forest-only loss was 127,473 km(2) (1.05% annually). In the NFPP provinces, the forest-only loss rate was 0.62%, which was 3.3 times lower than in the non-NFPP provinces. Moreover, the Landsat data suggest that these loss rates are overestimates due to large MODIS pixel size. Thus, China appears to have achieved, and even exceeded, its target of reducing deforestation to 1.1% annually in the NFPP provinces. About two-thirds of China's NNRs were effective in protecting forest cover (prevented loss 4073 km(2) unmatched approach; 3148 km(2) matched approach), and within-NNR deforestation rates were higher in provinces with higher overall deforestation. Our results indicate that China's existing institutions can protect domestic forest cover. © 2015 The Authors

  1. Method of forming latent image to protect documents based on the effect moire

    OpenAIRE

    Troyan, О.

    2015-01-01

    Analysis of modern methods of information protection based on printed documents. It is shown that methods of protection from moiré effect provide reliable and effective protection by gaining new protection technology that is displayed in the optical acceleration motion layers and causes moire in fraud. Latent images can securely protect paper documents. Introduce a system of equations to calculate curvilinear patterns, where the optical formula of acceleration and periods moire stored in i...

  2. Protective effects of dark chocolate on endothelial function and diabetes.

    Science.gov (United States)

    Grassi, Davide; Desideri, Giovambattista; Ferri, Claudio

    2013-11-01

    Relationship between cocoa consumption and cardiovascular disease, particularly focusing on clinical implications resulting from the beneficial effects of cocoa consumption on endothelial function and insulin resistance. This could be of clinical relevance and may suggest the mechanistic explanation for the reduced risk of cardiovascular events reported in the different studies after cocoa intake. Increasing evidence supports a protective effect of cocoa consumption against cardiovascular disease. Cocoa and flavonoids from cocoa have been described to improve endothelial function and insulin resistance. A proposed mechanism could be considered in the improvement of the endothelium-derived vasodilator nitric oxide by enhancing nitric oxide synthesis or by decreasing nitric oxide breakdown. The endothelium plays a pivotal role in the arterial homeostasis, and insulin resistance is the most important pathophysiological feature in various prediabetic and diabetic states. Reduced nitric oxide bioavailability with endothelial dysfunction is considered the earliest step in the pathogenesis of atherosclerosis. Further, insulin resistance could account, at least in part, for the endothelial dysfunction. Endothelial dysfunction has been considered an important and independent predictor of future development of cardiovascular risk and events. Cocoa and flavonoids from cocoa might positively modulate these mechanisms with a putative role in cardiovascular protection.

  3. Recovery behavior of high purity cubic SiC polycrystals by post-irradiation annealing up to 1673 K after low temperature neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Idris, Mohd Idzat, E-mail: idzat.i.aa@m.titech.ac.jp [Department of Nuclear Engineering, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8550 Japan (Japan); The National University of Malaysia, School of Applied Physics, Faculty of Science and Technology, 43600 Bangi Selangor (Malaysia); Yamazaki, Saishun; Yoshida, Katsumi; Yano, Toyohiko [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8550 Japan (Japan)

    2015-10-15

    Two kinds of high purity cubic (β) SiC polycrystals, PureBeta-SiC and CVD-SiC, were irradiated in the BR2 reactor (Belgium) up to a fluence of 2.0–2.5 × 10{sup 24} (E > 0.1 MeV) at 333–363 K. Changes in macroscopic lengths were examined by post-irradiation thermal annealing using a precision dilatometer up to 1673 K with a step-heating method. The specimen was held at each temperature step for 6 h and the change in length of the specimen was recorded during each isothermal annealing step from 373 K to 1673 K with 50 K increments. The recovery curves were analyzed with the first order model, and rate constants at each annealing step were obtained. Recovery of defects, induced by neutron irradiation in high purity β-SiC, has four stages of different activation energies. At 373–573 K, the activation energy of PureBeta-SiC and CVD-SiC was in the range of 0.17–0.24 eV and 0.12–0.14 eV; 0.002–0.04 eV and 0.006–0.04 eV at 723–923 K; 0.20–0.27 eV and 0.26–0.31 eV at 923–1223 K; and 1.37–1.38 eV and 1.26–1.29 eV at 1323–1523 K, respectively. Below ∼1223 K the recombination occurred possibly for closely positioned C and Si Frenkel pairs, and no long range migration is deemed essential. Nearly three-fourths of recovery, induced by neutron irradiation, occur by this mechanism. In addition, at 1323–1523 K, recombination of slightly separated C Frenkel pairs and more long-range migration of Si interstitials may have occurred for PureBeta-SiC and CVD-SiC specimens. Migration of both vacancies may be restricted up to ∼1523 K. Comparing to hexagonal α-SiC, high purity β-SiC recovered more quickly in the lower annealing temperature range of less than 873 K, in particular less than 573 K. - Highlights: • Two kinds of high purity cubic (β) SiC polycrystals were irradiated. • Macroscopic lengths were examined by post-irradiation thermal annealing. • The recovery curves were analyzed with first order model.

  4. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    International Nuclear Information System (INIS)

    Farah, K.; Kuntz, F.; Kadri, O.; Ghedira, L.

    2004-01-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by 2.2 MeV electrons beam accelerator and post irradiation storage on the response of several types of dosimeter films. All dosimeters showed a significant effect of temperature during irradiation and post-irradiation storage

  5. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Farah, K. E-mail: k.farah@cnstn.rnrt.tn; Kuntz, F.; Kadri, O.; Ghedira, L

    2004-10-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by 2.2 MeV electrons beam accelerator and post irradiation storage on the response of several types of dosimeter films. All dosimeters showed a significant effect of temperature during irradiation and post-irradiation storage.

  6. Late post-irradiation phenomena in mammalain cell populations. Pt. 2. Intraclonal recovery in sublines isolated from X-irradiated L5178Y-S cell populations

    International Nuclear Information System (INIS)

    Beer, J.Z.

    1975-01-01

    Clonal analysis of L5178Y-S cell populations irradiated with 300 rads of X-rays indicates occurence of cell sublines with considerably prolonged mean doubling times up to 22 h as compared to 10-11 h for control. Subsequent observations of growth of the handicapped sublines derived from single cells showed capability of all more than 100 studied sublines to recover normal proliferative activity. This process of intraclonal recovery required in many cases longer periods of time, corresponding to many tens, sometimes more than 200, generations. Late intraclonal recovery was further analysed by subcloning. It was found that although cytochemically assayed viability of the handicapped sublines was normal, cloning efficiency strongly depended on the stage of the recovery process. The recovery processes occuring in clones isolated from irradiated cell populations were compared with analogous processes occuring in slowly growing sublines isolated from non-irradiated cell cultures. Marked differences in kinetics of these processes show that either they are different in sublines derived from irradiated and non-irradiated cell populations or that the mechanisms of the late intraclonal recovery are affected by radiation. The results presented allow to conclude that gradual post-irradiation recovery of growth depends primarily on formation, in the developing populations, of cells with higher proliferative activities. Possible nature of the recovery processes is discussed in the light of available information on mammalian somatic cell variants with altered drug or temperature sensitivity, or with nutritional requirements. A sequence is proposed of changes leading from radiation-induced disturbance of the normably existing equilibrium between three basic cell subpopulations to ultimate restoration of this equilibrium. (author)

  7. Comparing the impact of melatonin and captopril on early effects of radiation on the heart tissue by studying glutathione, malondialdehyde, and lactate dehydrogenase enzyme activity in rats

    International Nuclear Information System (INIS)

    Shirazi, Alireza; Tabatabaie, Farnaz; Ghazi-Khansari, Mahmoud; Mirzaei, Hamidreza

    2015-01-01

    Prevention of secondary malignancy while the patient is receiving radiotherapy for the management of primary cancer has been an enormous challenge for biological and medical safety. The aim of the study is to compare protective effects of melatonin and captopril on early effects of radiation on the heart tissue of rats. Forty-eight adult male Wistar rats weighing 180-220 g were used. The rats were divided into six groups and the rats were exposed to 8 Gy whole body dose from Cobalt-60 sources. Thirty minutes prior to irradiation, six animals received melatonin (100 mg/kg body weight), and six animals received captopril (50 mg/kg body weight). All groups were sacrificed 10 days post-irradiation, and hearts were collected. Malondialdehyde (MDA), lactate dehydrogenase (LDH), and glutathione (GSH) were measured to evaluate cellular oxidative stress-induced injury. The biochemical data are presented as mean ± standard error of the mean, and the difference between the groups was analyzed using a two-way variance analysis. Treatment with captopril resulted in a significant increase in LDH and MDA, although the level of GSH was decreased (P < 0.01). MDA and LDH levels were decreased after melatonin treatment while GSH level was increased (P < 0.001). Melatonin has protective effects following radiation, while treatment with captopril post-irradiation seems to be radiosensitizing and does not have protective effects against radiation exposure. (author)

  8. Bioavailability, metabolism and potential health protective effects of dietary flavonoids

    DEFF Research Database (Denmark)

    Bredsdorff, Lea

    Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several...... epidemiological studies but the evidence is inconclusive. One major obstacle for epidemiological studies investigating associations between flavonoid intake and risk of CHD is the estimation of flavonoid intake. There is a vast variety of flavonoids in commonly eaten food products but only limited knowledge...... of their content. In addition, variation in individual metabolic genotype and microflora may greatly affect the actual flavonoid exposure. The preventive effects of flavonoids on CHD are mainly ascribed to their anti-inflammatory and antioxidant activities. Several mechanisms of anti-inflammatory and antioxidant...

  9. Post irradiation examination and experience

    International Nuclear Information System (INIS)

    1985-11-01

    The present meeting was scheduled by the International Atomic Energy Agency upon proposal from the members of the International Working Group on Water Reactor Fuel Performance and Technology. At the invitation of the Government of Japan, Japan Atomic Energy Research Institute and Nuclear Safety Research Association (of Japan), organized the meeting in Tokyo. 37 participants representing 13 countries and one international organization attended the meeting. 27 papers were presented in three sessions, namely: general fuel testing programme (3 papers), fuel performance study (10 papers), in-core, on-site and hot cell technique (8 papers). A separate abstract was prepared for each of these papers. Three syndicate meetings allowed participants to discuss the papers and to draw up conclusions and recommendations

  10. Protective Effect of Dietary Xylitol on Influenza A Virus Infection

    Science.gov (United States)

    Yin, Sun Young; Kim, Hyoung Jin; Kim, Hong-Jin

    2014-01-01

    Xylitol has been used as a substitute for sugar to prevent cavity-causing bacteria, and most studies have focused on its benefits in dental care. Meanwhile, the constituents of red ginseng (RG) are known to be effective in ameliorating the symptoms of influenza virus infection when they are administered orally for 14 days. In this study, we investigated the effect of dietary xylitol on influenza A virus infection (H1N1). We designed regimens containing various fractions of RG (RGs: whole extract, water soluble fraction, saponin and polysaccharide) and xylitol, and combination of xylitol with the RG fractions. Mice received the various combinations orally for 5 days prior to lethal influenza A virus infection. Almost all the mice died post challenge when xylitol or RGs were administered separately. Survival was markedly enhanced when xylitol was administered along with RGs, pointing to a synergistic effect. The effect of xylitol plus RG fractions increased with increasing dose of xylitol. Moreover, dietary xylitol along with the RG water soluble fraction significantly reduced lung virus titers after infection. Therefore, we suggest that dietary xylitol is effective in ameliorating influenza-induced symptoms when it is administered with RG fractions, and this protective effect of xylitol should be considered in relation to other diseases. PMID:24392148

  11. Protective effect of dietary xylitol on influenza A virus infection.

    Directory of Open Access Journals (Sweden)

    Sun Young Yin

    Full Text Available Xylitol has been used as a substitute for sugar to prevent cavity-causing bacteria, and most studies have focused on its benefits in dental care. Meanwhile, the constituents of red ginseng (RG are known to be effective in ameliorating the symptoms of influenza virus infection when they are administered orally for 14 days. In this study, we investigated the effect of dietary xylitol on influenza A virus infection (H1N1. We designed regimens containing various fractions of RG (RGs: whole extract, water soluble fraction, saponin and polysaccharide and xylitol, and combination of xylitol with the RG fractions. Mice received the various combinations orally for 5 days prior to lethal influenza A virus infection. Almost all the mice died post challenge when xylitol or RGs were administered separately. Survival was markedly enhanced when xylitol was administered along with RGs, pointing to a synergistic effect. The effect of xylitol plus RG fractions increased with increasing dose of xylitol. Moreover, dietary xylitol along with the RG water soluble fraction significantly reduced lung virus titers after infection. Therefore, we suggest that dietary xylitol is effective in ameliorating influenza-induced symptoms when it is administered with RG fractions, and this protective effect of xylitol should be considered in relation to other diseases.

  12. Protective effect of EDTA preadministration on renal ischemia

    Directory of Open Access Journals (Sweden)

    Belloni Daniela

    2006-03-01

    Full Text Available Abstract Background Chelation therapy with sodium edetate (EDTA improved renal function and slowed the progression of renal insufficiency in patients subjected to lead intoxication. This study was performed to identify the underlying mechanism of the ability of EDTA treatment to protect kidneys from damage. Methods The effects of EDTA administration were studied in a rat model of acute renal failure induced by 60 minutes ischemia followed or not by 60 minutes reperfusion. Renal ischemic damage was evaluated by histological studies and by functional studies, namely serum creatinine and blood urea nitrogen levels. Treatment with EDTA was performed 30 minutes before the induction of ischemia. Polymorphonuclear cell (PMN adhesion capability, plasmatic nitric oxide (NO levels and endothelial NO synthase (eNOS renal expression were studied as well as the EDTA protection from the TNFα-induced vascular leakage in the kidneys. Data was compared by two-way analysis of variance followed by a post hoc test. Results EDTA administration resulted in the preservation of both functional and histological parameters of rat kidneys. PMN obtained from peripheral blood of EDTA-treated ischemized rats, displayed a significant reduction in the expression of the adhesion molecule Mac-1 with respect to controls. NO was significantly increased by EDTA administration and eNOS expression was higher and more diffuse in kidneys of rats treated with EDTA than in the controls. Finally, EDTA administration was able to prevent in vivo the TNFα-induced vascular leakage in the kidneys. Conclusion This data provides evidence that EDTA treatment is able to protect rat kidneys from ischemic damage possibly through the stimulation of NO production.

  13. Melatonin Protective Effects against Liver Ischemia/Reperfusion Injury

    Directory of Open Access Journals (Sweden)

    Abbas Khonakdar-Tarsi

    2016-02-01

    Full Text Available Hepatic ischemia-reperfusion (I/R is a common phenomenon during liver surgery, transplantation, infection and trauma which results in damage and necrosis of the hepatic tissue through different pathways. Mechanisms involved in I/R damage are very intricate and cover several aspects. Several factors are involved in I/R-induced damages; briefly, decrease in sinusoidal perfusion and ATP generation because of low or no O2 supply, increase in production of reactive oxygen species (ROS and inflammatory factors and destruction of parenchymal cells resulted by these molecules are of the main causes of liver tissue injury during reperfusion. Melatonin’s antioxidant effect, and regulatory roles in the expression of different genes in the I/R insulted liver have been investigated by several studies. Melatonin and its metabolites are of the powerful direct scavengers of free radicals and ROS, so it can directly protect liver cell impairment from oxidative stress following I/R. In addition, this bioactive molecule up-regulates anti-oxidant enzyme genes like superoxide dismutase (SOD, glutathione peroxidase (GSH-Px and catalase (CAT. Tumor necrosis factors (TNF-α and interleukin-1 (IL-1, as potent pro-inflammatory factors, are generated in huge amounts during reperfusion. Melatonin is able to alleviate TNF-α generation and has hepatoprotective effect during I/R. It reduces the production of pro-inflammatory cytokines and chemokines via reducing the binding of NF-κB to DNA. Imbalance between vasodilators (nitric oxide, NO and vasoconstrictors (endothelin, ET during I/R was shown to be the primary cause of liver microcirculation disturbance. Melatonin helps maintaining the stability of liver circulation and reduces hepatic injury during I/R through preventing alteration of the normal balance between ET and NO. The aim of this review was to explore the mechanisms of liver I/R injuries and the protective effects of melatonin against them.

  14. Protective effect of agmatine in acute chlorpromazine hepatotoxicity in rats

    Directory of Open Access Journals (Sweden)

    Bratislav Dejanovic

    2014-01-01

    Full Text Available The present study focused on potentially beneficial effects of agmatine on oxidative stress development in the liver during chlorpromazine treatment in rats. We wanted to examine the role of reactive oxygen species and efficiency of antioxidant protection through the determination of malondylaldehyde and total glutathione concentrations in rat liver homogenate, as well as plasma concentrations of malonylaldehyde and sulfhydryl groups after the treatment. Also, liver tissue sections were examined to follow histological changes. Chlorpromazine was applied intraperitoneally at a single dose of 38.7 mg/kg b.w. The second group was treated with both chlorpromazine (at a single dose of 38.7 mg/kg b.w. and agmatine (at a single dose of 75 mg/kg b.w.. Agmatine was applied immediately after the chlorpromazine. The control group was treated with 0.9% saline solution in the same manner. Rats were sacrificed by decapitation 24 h after the treatment and biochemical and immunohistochemical examinations were performed. Analysis of data showed that treatment with agmatine significantly attenuated the oxidative stress indicators as evidenced by lowering malonylaldehyde concentrations in the liver and in plasma while not affecting liver concentrations of total glutathione and plasma concentration of sulfhydryl groups. Additionally, histological evaluation revealed the improvement of liver damage in this respect. The presented data indicated that intraperitoneally administered agmatine protects against chlorpromazine-induced liver disease in rats.

  15. The protective effect of ebselen on radiocontrast-induced nephrotoxicity.

    Science.gov (United States)

    Ozgur, Tumay; Tutanc, Murat; Zararsiz, Ismail; Motor, Sedat; Ozturk, Oktay Hasan; Yaldiz, Mehmet; Kurtgoz, Ozgur Yildirim

    2012-01-01

    Radiocontrast-induced nephropathy has become one of the most important causes of renal acute failure. The most effective management of reducing the incidence of contrast nephropathy is to understand and prevent its causes. We aimed to investigate the protective role of ebselen against radiocontrast-induced nephrotoxicity in terms of tissue oxidant/antioxidant parameters and light microscopy in rats. Albino Wistar rats were randomly separated into four groups. The Group 1 rats were treated with sodium chloride as the control group, Group 2 with radiocontrast, Group 3 with radiocontrast plus ebselen, and Group 4 with ebselen alone. After 24 h, the animals over the experimental period were euthanized and blood samples were analyzed for blood urea nitrogen (BUN) and serum creatinine (Cr) levels. Kidney sections were analyzed for malondialdehyde (MDA) levels and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities, as well as histopathological changes. In the radiocontrast group, BUN, MDA, and GSH-Px levels increased while SOD activity decreased compared with the control group. These decays were improved by ebselen administration in the radiocontrast group. Significant histological deteriorations were observed in the radiocontrast group. We noted improvement in the histologic findings with ebselen administration. These results indicate that ebselen might produce a protective mechanism against radiocontrast-induced nephrotoxicity.

  16. Protective effect of melatonin on thrombocytopoiesis in irratiated mice

    International Nuclear Information System (INIS)

    Liu Aiguo; Hu Qun; Yang Mo; Li Zhiguang; Huang Weizhe; Pang Yaxuan; Li Guixia; Wu Baixiang; Huo Taihui

    2005-01-01

    Objective: To study the protective effect of melatonin on thrombocytopoiesis (T) and its mechanism in total-bodily irradiated mice. Methods: Altogether 18 female BALB/c mice were randomly divided into three experimental groups (6 each): Group 1(normal control, N) received neither irradiation nor melatonin; Group 2 (model control, C); received total body-irradiation for 4 Gy gamma-rays and Group 3 (melatonin, M), received melatonin after irradiation at the dosage of 10 mg·kg -1 ·d -1 via i. p. injection in consecutive 21 days. In Group C normal saline instead of melatonin was administered in the same way as above. Peripheral blood platelets and white blood cells (WBC) were analyzed for the three groups on day 0, day 7, day 14, and day 21. All the mice were sacrificed to collect bone marrow cells for the assays of colony-forming unit-megakaryocyte (CFU-MK) and of colony-forming unit-fibroblast (CFU-F). The effects of melatonin of different concentrations (0-500 nmol/L) on CFU-MK formation were observed in vitro. Results: The results showed that melatonin enhanced the recovery of T. Moreover, melatonin also promoted the increase of CFU-F (28 ± 10.4 vs 14.6 ± 2.8) and CFU-MK (19.63 ± 3.28 vs 11 ± 2.24) in vivo. The amount of CFU-MK in vitro was dependent on the concentration of melatonin. Compared with the control group, the size of CFU-MK in Group M was much larger and MK cells were more mature, especially when the melatonin concentration was 200 nmol/L. Conclusion: Melatonin provides protective effect on T in irradiated mice. It enhances T in vivo and promotes the growth of bone marrow stromal cells as well as megakaryocytes in vitro. Therefore, we speculate that the T-protective activity of melatonin may be mediated via promoting growth of the progenitors of platelet, megakaryocytes, and bone marrow stromal cells. (authors)

  17. Investigating the Protective Effects of Vitamin D on Diabete

    Directory of Open Access Journals (Sweden)

    makan Cheraghpour

    2014-06-01

    Full Text Available Vitamin D directly (due to receptor activation by vitamin D or indirectly (through regulation of calcium homeostasis effects on the pathogenic mechanisms associated with both types of diabetes, such as pancreatic beta-cell dysfunction, impaired insulin action and systemic inflammation. It has been shown that using Vitamin D supplementation during pregnancy and infancy has relation with a reduced risk of type 1 diabetes. In non-obese diabetic mice studies, pharmacological doses of vitamin D can delay the onset of diabetes. Any direct link between vitamin D and risk of type 2 diabetes has not been established yet, however many questions such as the concentration of vitamin D for optimal glucose homeostasis and how long pursuit to understand the effect of vitamin D on insulin secretion and sensitivity is essential have not been fully answered. The use of 1, 25 (OH 2D3 for preventing or treating diabetes through its hypercalcemic effects and bone turnover is limited. On the other hand however, the protective effects only observed in response to doses higher than the physiological levels. In any case, a better understanding of the role of vitamin D can lead to the development of preventive strategies for both types of diabetes..

  18. Protective Effect of Laminaria japonica with Probiotics on Murine Colitis

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    Seok-Jae Ko

    2014-01-01

    Full Text Available Inflammatory bowel disease (IBD is a chronically relapsing inflammatory disorder of the gastrointestinal tract. Most IBD treatments are unsatisfactory; therefore, various dietary supplements have emerged as promising interventions. Laminaria japonica (LJ is an edible seaweed used to regulate digestive symptoms. Probiotics have been reported to improve digestive problems and their simultaneous administration with seaweeds has been shown to produce synergistic therapeutic effects. Here, we investigated the effect of LJ combination with probiotics on dextran sodium sulfate-induced colitis model in mice. Aqueous LJ extracts (LJE at doses from 100 to 300 mg/kg and probiotics at a dose of 300 mg/kg were orally administered for 7 days. Body weight, colon length, histological score, macroscopic damage, and the levels of cytokines IFN-γ, IL-1β, IL-6, IL-10, IL-12 (P40, IL-12 (P70, IL-17, and TNF-α were assessed. LJE alone caused a significant improvement of colitis signs such as colon length, histological score, and IL-1β and IL-6 production. LJE and probiotics demonstrated a synergistic effect by the histological score and levels of IL-1β, IL-6, and IL-12 (P40 but not IFN-γ, IL-10, and IL-12 (P70. In conclusion, LJE was effective in inducing protection against colitis in mice and acted synergistically with probiotics.

  19. Effectively protecting cyber infrastructure and assessing security needs

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, J.; Starman, R. [EWA Canada Ltd., Edmonton, AB (Canada)

    2002-07-01

    This presentation addressed some of the requirements for effectively protecting cyber infrastructure and assessing security needs. The paper discussed the hype regarding cyber attacks, and presented the Canadian reality (as viewed by CanCERT). An assessment of security concerns was also presented. Recent cyber attacks on computer networks have raised fears of unsafe energy networks. Some experts claim the attacks are linked to terrorism, others blame industrial spying and mischief. Others dismiss the notion that somebody could bring down a power grid with a laptop as being far-fetched. It was noted that the cyber security threat is real, and that attacks are becoming more sophisticated as we live in a target rich environment. The issue of assessing vulnerabilities was discussed along with the selection of safeguards such as improving SCADA systems and the latest encryption methods to prevent hackers from bringing down computer networks. 3 tabs., 23 figs.

  20. Meniscal repair following meniscectomy: Mechanism and protective effect

    International Nuclear Information System (INIS)

    Berjon, J.J.; Munuera, L.; Calvo, M.

    1990-01-01

    Meniscal repair was studied to evaluate the mechanism and its potential protective effects on the articular cartilage in an experimental model consisting of 68 knees of adult dogs on which five different types of medial meniscectomy were performed. The results were assessed by macroscopic, microangiographic, and histological methods, after a sequential follow-up period of 10-450 days. Two different mechanisms of meniscal repair were observed, depending on whether meniscal section had been performed in vascular (total meniscectomy) or avascular (subtotal or partial meniscectomy) zones. It was also observed that the repaired meniscal tissue does not prevent articular cartilage degeneration. This is more closely related to the size of the meniscal fragment preserved at meniscetomy. Due to the biomechanical importance of the meniscus and the lack of functional relevance of the repaired meniscal tissue, the most conservative approach possible to meniscectomy is recommended. (orig.)

  1. The effect of radiological protection standards on the uranium market

    International Nuclear Information System (INIS)

    Francois, Y.; Pradel, J.; Zettwoog, P.

    1975-01-01

    On the basis of concrete results obtained in the CEA's uranium mines over a period of 15 years, the authors determine to what extent the costs of radiological protection affect the price of uranium. The principles on which radiological protection is organized in the CEA mines are mentioned. Emphasis is placed on the precautions which have to be taken in order to ensure that radioactivity measurements are representative despite the extreme complexity and the variability of conditions in the workings. A description is given of the way in which the operation of the ventilation system is varied on the basis of radioactivity measurements as the workings are extended. The authors conclude that in the CEA mines, where the uranium content in the ores frequently exceeds one per cent, it is possible to ensure that the current standard is actually adhered to and that nevertheless the cost of radiological protection remains marginal. In the second part of the paper the possible effects of increasing the stringency of the standards are examined. The considerations are based on several thousands of measurements carried out in various workings and galleries. It is shown that the correlation between radon concentration and ore content is weak. It is pointed out that the state of equilibrium of radon daughters in the workings is of the order of 0.2 rather than the 0.5 assumed in the standard. On this basis the mean level of actual exposure, in total alpha energy, is of the order of 20% of the value 1.3 x 10 5 MeV α/litre, the level of the most highly exposed worker being 80% of that value. In addition, it is shown that with simple improvements to the design of the ventilation circuits and elementary precautions it is often possible to ''rejuvenate'' the radon in the workings and influence still further the state of equilibrium of the daughters. Finally, preliminary results obtained in the experimental mine at La Crouzille indicate that the radon concentration can be further

  2. Protective effects of L-selenomethionine on space radiation induced changes in gene expression.

    Science.gov (United States)

    Stewart, J; Ko, Y-H; Kennedy, A R

    2007-06-01

    Ionizing radiation can produce adverse biological effects in astronauts during space travel. Of particular concern are the types of radiation from highly energetic, heavy, charged particles known as HZE particles. The aims of our studies are to characterize HZE particle radiation induced biological effects and evaluate the effects of L-selenomethionine (SeM) on these adverse biological effects. In this study, microarray technology was used to measure HZE radiation induced changes in gene expression, as well as to evaluate modulation of these changes by SeM. Human thyroid epithelial cells (HTori-3) were irradiated (1 GeV/n iron ions) in the presence or in the absence of 5 microM SeM. At 6 h post-irradiation, all cells were harvested for RNA isolation. Gene Chip U133Av2 from Affymetrix was used for the analysis of gene expression, and ANOVA and EASE were used for a determination of the genes and biological processes whose differential expression is statistically significant. Results of this microarray study indicate that exposure to small doses of radiation from HZE particles, 10 and 20 cGy from iron ions, induces statistically significant differential expression of 196 and 610 genes, respectively. In the presence of SeM, differential expression of 77 out of 196 genes (exposure to 10 cGy) and 336 out of 610 genes (exposure to 20 cGy) is abolished. In the presence or in the absence of SeM, radiation from HZE particles induces differential expression of genes whose products have roles in the induction of G1/S arrest during the mitotic cell cycle, as well as heat shock proteins. Some of the genes, whose expressions were affected by radiation from HZE particles and were unchanged in irradiated cells treated with SeM, have been shown to have altered expression levels in cancer cells. The conclusions of this report are that radiation from HZE particles can induce differential expression of many genes, some of which are known to play roles in the same processes that have

  3. Teaching effective problem solving skills to radiation protection students

    International Nuclear Information System (INIS)

    Waller, Edward

    2008-01-01

    Full text: Problem solving skills are essential for all radiation protection personnel. Although some students have more natural problem solving skills than others, all students require practice to become comfortable using these skills. At the University of Ontario Institute of Technology (UOIT), a unique one-semester course was developed as part of the core curriculum to teach students problem solving skills and elements of modelling and simulation. The underlying emphasis of the course was to allow students to develop their own problem solving strategies, both individually and in groups. Direction was provided on how to examine problems from different perspectives, and how to determine the proper root problem statement. A five-point problem solving strategy was presented as: 1) Problem definition; 2) Solution generation; 3) Decision; 4) Implementation; 5) Evaluation. Within the strategy, problem solving techniques were integrated from diverse areas such as: De Bono 's six thinking hats, Kepner-Tregoe decision analysis, Covey's seven habits of highly effective people, Reason's swiss cheese theory of complex failure, and Howlett's common failure modes. As part of the evaluation step, students critically explore areas such as ethics and environmental responsibility. In addition to exploring problem solving methods, students learn the usefulness of simulation methods, and how to model and simulate complex phenomena of relevance to radiation protection. Computational aspects of problem solving are explored using the commercially available MATLAB computer code. A number of case studies are presented as both examples and problems to the students. Emphasis was placed on solutions to problems of interest to radiation protection, health physics and nuclear engineering. A group project, pertaining to an accident or event related to the nuclear industry is a course requirement. Students learn to utilize common time and project management tools such as flowcharting, Pareto

  4. Protecting effect on gamma-ray damage of DNA by tea catechin

    International Nuclear Information System (INIS)

    Yoshioka, H.; Akai, G.; Yoshinaga, K.; Hasegawa, K.; Yoshioka, H.

    1995-01-01

    The protecting effect of the tea catechin on the radiation induced scission of DNA in vitro. was examined. In addition, ESR spin-trapping method was used to make clear the mechanism of the protection. (author)

  5. [Protective effects of compound shenhua tablet on diabetic nephropathy rats].

    Science.gov (United States)

    Geng, Wen-Jia; Wei, Ri-Bao; Mao, Wei

    2012-03-01

    To observe the renal protection effects of Compound Shenhua Tablet (CST) on diabetic nephropathy (DN) rats. DN rats were given a normal diet for 9 months after they were induced by intraperitoneal injection of STZ at the dose of 65 mg/kg after uninephrectomized. They were randomly divided into 4 groups, i. e., the normal control group, the model control group, the CST group, and the Irbesartan group. The intervention was given by gastrogavage for 6 weeks. The general state, 24 h urine protein, urine micro-albumin (mAlb), serum creatinine (SCr), blood urea nitrogen (BUN), glucose (GLU), triglyceride (TG), total cholesterol (TC), total protein (TP), and albumin (ALB) levels were observed before and after intervention. Renal pathological changes were observed by PAS staining and transmission electron microscope. After 6 weeks of drug intervention, when compared with the model control group, the general state was improved in the CST group and the Irbesartan group. The levels of 24 h urine protein, urine mAlb, SCr, BUN, GLU, TG, and TC were obviously lower in the CST group and the Irbesartan group than in the model group as well as in the same group before treatment (P0.05). The renal pathological changes and the renal ultrastructure were improved to some degree in the two groups when compared with those in the model control group. CST could attenuate the renal damage of diabetes and delay renal deterioration process. Its effectiveness was equivalent to that of Irbesartan.

  6. Can selection explain the protective effects of farming on asthma?

    Directory of Open Access Journals (Sweden)

    Wijnand Eduard

    2015-09-01

    Full Text Available [i][/i]Introduction and objective. Reduced asthma and allergy risks in farmers have been ascribed to microbial exposures. However, selection may also play a role and this was assessed in two Scandinavian farming populations. Materials and methods. Asthma prevalence in 739 Danish farming students was compared to that of 1,105 siblings. 8,482 Norwegian farmers were also compared with 349 early retired farmers. Results. The prevalence of ever-asthma was 5.4% in farming students and 5.2% in siblings (OR 1.1; 95%CI 0.73–1.7. Current asthma in farmers was 3.0% compared to 6.3% in farmers who had retired early (OR 1.8, 95%CI 1.1–2.9. Adjustments for early retirement increased the asthma prevalence by 0.3–0.6%. Farmers who had changed production were more likely to have asthma (OR 9.8, 95% CI 6.0–16. Conclusions. No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.

  7. Protective Effects of Selected Botanical Agents on Bone

    Directory of Open Access Journals (Sweden)

    James Jam Jolly

    2018-05-01

    Full Text Available Osteoporosis is a serious health problem affecting more than 200 million elderly people worldwide. The early symptoms of this disease are hardly detectable. It causes progressive bone loss, which ultimately renders the patients susceptible to fractures. Osteoporosis must be prevented because the associated fragility fractures result in high morbidity, mortality, and healthcare costs. Many plants used in herbal medicine contain bioactive compounds possessing skeletal protective effects. This paper explores the anti-osteoporotic properties of selected herbal plants, including their actions on osteoblasts (bone forming cells, osteoclasts (bone resorbing cells, and bone remodelling. Some of the herbal plant families included in this review are Berberidaceae, Fabaceae, Arecaceae, Labiatae, Simaroubaceaea, and Myrsinaceae. Their active constituents, mechanisms of action, and pharmaceutical applications were discussed. The literature shows that very few herbal plants have undergone human clinical trials to evaluate their pharmacological effects on bone to date. Therefore, more intensive research should be performed on these plants to validate their anti-osteoporotic properties so that they can complement the currently available conventional drugs in the battle against osteoporosis.

  8. Protective Effects of Hydrogen Sulfide in the Ageing Kidney.

    Science.gov (United States)

    Hou, Cui-Lan; Wang, Ming-Jie; Sun, Chen; Huang, Yong; Jin, Sheng; Mu, Xue-Pan; Chen, Ying; Zhu, Yi-Chun

    2016-01-01

    Aims . The study aimed to examine whether hydrogen sulfide (H 2 S) generation changed in the kidney of the ageing mouse and its relationship with impaired kidney function. Results . H 2 S levels in the plasma, urine, and kidney decreased significantly in ageing mice. The expression of two known H 2 S-producing enzymes in kidney, cystathionine γ -lyase (CSE) and cystathionine- β -synthase (CBS), decreased significantly during ageing. Chronic H 2 S donor (NaHS, 50  μ mol/kg/day, 10 weeks) treatment could alleviate oxidative stress levels and renal tubular interstitial collagen deposition. These protective effects may relate to transcription factor Nrf2 activation and antioxidant proteins such as HO-1, SIRT1, SOD1, and SOD2 expression upregulation in the ageing kidney after NaHS treatment. Furthermore, the expression of H 2 S-producing enzymes changed with exogenous H 2 S administration and contributed to elevated H 2 S levels in the ageing kidney. Conclusions . Endogenous hydrogen sulfide production in the ageing kidney is insufficient. Exogenous H 2 S can partially rescue ageing-related kidney dysfunction by reducing oxidative stress, decreasing collagen deposition, and enhancing Nrf2 nuclear translocation. Recovery of endogenous hydrogen sulfide production may also contribute to the beneficial effects of NaHS treatment.

  9. Protective effects of dietary chamomile tea on diabetic complications.

    Science.gov (United States)

    Kato, Atsushi; Minoshima, Yuka; Yamamoto, Jo; Adachi, Isao; Watson, Alison A; Nash, Robert J

    2008-09-10

    Matricaria chamomilla L., known as "chamomile", has been used as an herbal tea or supplementary food all over the world. We investigated the effects of chamomile hot water extract and its major components on the prevention of hyperglycemia and the protection or improvement of diabetic complications in diabetes mellitus. Hot water extract, esculetin (3) and quercetin (7) have been found to show moderate inhibition of sucrase with IC50 values of 0.9 mg/mL and 72 and 71 microM, respectively. In a sucrose-loading test, the administration of esculetin (50 mg/kg body weight) fully suppressed hyperglycemia after 15 and 30 min, but the extract (500 mg/kg body weight) and quercetin (50 mg/kg body weight) were less effective. On the other hand, a long-term feed test (21 days) using a streptozotocin-induced rat diabetes model revealed that the same doses of extract and quercetin showed significant suppression of blood glucose levels. It was also found that these samples increased the liver glycogen levels. Moreover, chamomile extract showed potent inhibition against aldose reductase (ALR2), with an IC50 value of 16.9 microg/mL, and its components, umbelliferone (1), esculetin (3), luteolin (6), and quercetin (7), could significantly inhibit the accumulation of sorbitol in human erythrocytes. These results clearly suggested that daily consumption of chamomile tea with meals could contribute to the prevention of the progress of hyperglycemia and diabetic complications.

  10. Ebola virus disease: Effects of respiratory protection on healthcare workers

    Directory of Open Access Journals (Sweden)

    Hanan Mohammed Mohammed

    2015-07-01

    Full Text Available Ebola virus disease outbreak in West Africa sends an alarming message to all countries in the world, to increase the level of coordination and application of preventive measures globally to avoid a disastrous epidemic in the World, as the current situation in West Africa is critical especially after the World Health Organization increased the alarming level to an emergency in public health all over the world. Viral hemorrhagic fevers are important because they can readily spread within a hospital or mortuary setting, there is no effective cure or vaccine, they have a high mortality rate and they are difficult to recognize and diagnose rapidly. WHO has recommended respiratory protection for HCWs performing certain tasks such as aerosol-generating procedures, laboratory procedures, and autopsies. Particulate respirators are designed to help reduce the wearer’s exposure to certain airborne particles. The most effective way to block aerosolized particles is to use either a half-face or a full-face respirator. HCWs still need shoe covers, a full face respirator and latex or nitrile gloves to decrease the risk of Ebola virus contamination.

  11. Potential protective effect of honey against paracetamol-induced hepatotoxicity.

    Science.gov (United States)

    Galal, Reem M; Zaki, Hala F; Seif El-Nasr, Mona M; Agha, Azza M

    2012-11-01

    Paracetamol overdose causes severe hepatotoxicity that leads to liver failure in both humans and experimental animals. The present study investigates the protective effect of honey against paracetamol-induced hepatotoxicity in Wistar albino rats. We have used silymarin as a standard reference hepatoprotective drug. Hepatoprotective activity was assessed by measuring biochemical parameters such as the liver function enzymes, serum alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST). Equally, comparative effects of honey on oxidative stress biomarkers such as malondialdyhyde (MDA), reduced glutathione (GSH) and glutathione peroxidase (GPx) were also evaluated in the rat liver homogenates.  We estimated the effect of honey on serum levels and hepatic content of interleukin-1beta (IL-1β) because the initial event in paracetamol-induced hepatotoxicity has been shown to be a toxic-metabolic injury that leads to hepatocyte death, activation of the innate immune response and upregulation of inflammatory cytokines. Paracetamol caused marked liver damage as noted by significant increased activities of serum AST and ALT as well as the level of Il-1β. Paracetamol also resulted in a significant decrease in liver GSH content and GPx activity which paralleled an increase in Il-1β and MDA levels. Pretreatment with honey and silymarin prior to the administration of paracetamol significantly prevented the increase in the serum levels of hepatic enzyme markers, and reduced both oxidative stress and inflammatory cytokines. Histopathological evaluation of the livers also revealed that honey reduced the incidence of paracetamol-induced liver lesions. Honey can be used as an effective hepatoprotective agent against paracetamol-induced liver damage.

  12. The proceduralisation of data protection remedies under EU data protection law : Towards a more effective and data subject-oriented remedial system?

    NARCIS (Netherlands)

    Galetta, Antonella; de Hert, Paul

    2015-01-01

    The proceduralisation of data protection remedies under EU data protection law: towards a more effective and data subject-oriented remedial system?
The right to remedy breaches of data protection is laid down in both Directive 95/46/EC (Art. 22) and the Council of Europe Data Protection Convention

  13. Estimation of dependence between mean of fractionation of photons and neutrons dose and intensity of post-irradiation reaction of mouse large intestine; Ocena zaleznosci pomiedzy sposobem frakcjonowania dawki fotonow i neutronow a nasileniem popromiennego odczynu jelita grubego myszy

    Energy Technology Data Exchange (ETDEWEB)

    Gasinska, A. [Oncology Center, Cracow (Poland)

    1995-12-31

    The aim of the work was verification of mouse large intestine tolerance on fractionated 250 kV X-rays and 2.3 MeV neutrons doses. Two cm of large intestine of mouse CBA/HT strain were irradiated with various fraction doses: from 0.25 to 35 Gy of X-rays and 0.05-12 Gy of neutrons. The measure of injury was handicap of intestine function. Early post-irradiation reaction was measured by loss of body weight (2-3 weeks after irradiation) and mouse mortality (till 2 months after irradiation, LD50/2). The late reaction was measured on the base of maximal body weight in 1 year period after irradiation, deformation of excrements (after 10 months) and death of animals (till 12. month after irradiation, LD50/12). Fractionation of X-ray dose influenced on decrease of intensification of late irradiation effects. After fractionation of neutrons this effect has not been observed. {alpha}/{beta} coefficient for X-rays was 19.9 Gy [15.2; 27.0] for body weight nadir, 13.4 Gy [9.3; 19.5] for early mortality (LD50/2), 6.4 Gy [3.6;11.0] for maximal body weight and 6.9 [4.2; 10.8] for late mortality (LD50/12). Analysis of influence of low doses of photons 90.25-4 Gy) and neutrons (0.05-0.8 Gy) showed trend to reduction {alpha}/{beta} for photons only (LD50/2=5.4 Gy; LD50/12=4.6 Gy). {alpha}/{beta} coefficient for neutrons was defined by LQ model only for maximal body weight and was 19.9 Gy [9.5; 61.0]. In application of graphic method {alpha}/{beta} for neutrons was 230 Gy for early and 48 Gy for late effects. Lower values of {alpha}/{beta} coefficient for late irradiation effects for photon radiation demonstrate the big influence of fractionation of photons dose on large intestine tolerance (decrease intensity in all biological effects). Author did not observe increase of intestine tolerance in fractionation of neutrons dose. Effect of irradiation damages repair in interfraction pauses, measured by percent of regenerated dose (F{sub r}) was much bigger for photons. For X-rays it was 50

  14. The carrying capacity and the effects of protection level in three marine protected areas in the Balearic Islands (NW Mediterranean

    Directory of Open Access Journals (Sweden)

    Josep Coll

    2012-08-01

    Full Text Available The monitoring of fisheries target species in three marine protected areas (MPAs located in the NW Mediterranean provided important conclusions on management effects. The abundance, occurrence and biomass of large fish showed consistent and growing trends inside the MPAs. Fish diversity was also favoured by protection. Nevertheless, spatial variance of these indicators at a medium scale was often of the same order as that caused by time between different protection levels. The carrying capacity was determined for the first time in western Mediterranean MPAs in five out of six sites studied, and in all cases it was achieved within the first five years of protection. The observed values indicate that the system of the studied MPAs is representative of the general coastal environment of the Balearic Islands, but is far from the potential of other MPAs which are considered as hot spots in other localities. Likewise, this study shows that partially protected areas can also be fairly effective if their habitats fit with those required by target species and fishing modalities are suitably regulated or banned.

  15. [Protective effect of tanshinol on the hepatopulmonary syndrome in rat].

    Science.gov (United States)

    Jia, Jian-Tao; Zhang, Hui-Ying; Lai, Li-Na; Li, Xu-Jiong; Tian, Xiao-Xia; Zhang, Li-Li; Lv, Min-Li; Zhao, Zhong-Fu; Han, De-Wu; Cheng, Ji

    2014-05-01

    To explore the mechanism of tanshinol on alleviate the inflammatory injury of lung tissue in rat hepatopulmonary syndrome (HPS). SD rats were randomly divided into normal control group (n = 8), hepatopulmonary syndrome (HPS) group (n = 11) and tanshinol intervention group (n = 9). HE staining was used to observe the histopathology changes of pulmonary and hepatic tissues, and to count the number of macrophages in lung tissues. The activity of alanine transferase (ALT) and concentrations of endotoxin, tumor necrosis factor-a (TNF-alpha) and homocystein (Hcy) in plasma were detected. The concentrations of TNF-alpha, nitric oxide (NO) and malondialdehyde (MDA) and the activity of inducible nitric oxide synthase (iNOS) in the lung tissues were measured, respectively. Thickened alveolar septum and increased macrophages were observed in lungs in HPS rat. After administered with tanshinol, the pulmonary pathological changes were alleviated and the number of macrophages in lung tissue was decreased compared with HPS group. The activity of ALT and the concentrations of endotoxin, TNF-alpha and Hcy in plasma ,and TNF-alpha, iNOS, NO and MDA in lung tissue in HPS group were higher than those of normal control group; meanwhile, those tanshinol group were less those that of HPS group. Tanshinol may play an important role in delaying the development of HPS through protecting liver or directly antagonizing the effect of intestinal endotoxemia so as to alleviate the inflammatory reaction in lung tissue.

  16. Religiousness and Rape Myth Acceptance: Risk and Protective Effects.

    Science.gov (United States)

    Ensz, Samantha; Jankowski, Peter J

    2017-03-01

    This study addressed the lack of research simultaneously examining multiple dimensions of religiousness when predicting rape myth acceptance, and extended prior findings of a mediating role for right-wing authoritarianism (i.e., uncritical submission to authority and aggressive attitude toward those who do not conform to social norms) in the association between religiousness and prejudice. The sample consisted of 99 undergraduate and graduate students ( M age = 31.87 years, 66.7% female, 80.82% White, and 93% Christian affiliated) from a religiously affiliated university in the Midwest United States. As hypothesized, dimensions of religiousness exhibited differential associations with rape myth acceptance. Religious motivation characterized by openness and exploration (i.e., quest religiousness) was a significant negative predictor of rape myth acceptance, directly, and indirectly through right-wing authoritarianism. In contrast, rigid adherence to religious beliefs, assumed to be "right" and absolutely true (i.e., religious fundamentalism), and extrinsically motivated religiousness each exhibited a positive association with rape myth acceptance through right-wing authoritarianism. In addition, internally motivated religiousness and religious fundamentalism each moderated the nonlinear effect for quest predicting rape myth acceptance. Findings suggest that uncritical religious and secular submission to external authorities or uncommitted and nonexploring religiousness may have increased the extent to which persons adhered to rape myths, whereas religious exploration was protective. Practical implications center on the need for socioculturally relevant prevention and intervention efforts with religious identifying college students.

  17. Protective Effects of Flavonoid Pomiferin on Heart Ischemia-Reperfusion

    Directory of Open Access Journals (Sweden)

    J. Nečas

    2007-01-01

    Full Text Available The objective of the present 15-day study was to evaluate the cardioprotective potential of flavonoid pomiferin isolated from the infructences of Maclura pomifera, Moraceae, against ischemia-reperfusion induced injury in rat hearts as a model of antioxidant-based composite therapy. Studies were performed with isolated, modifi ed Langendorff-perfused rat hearts and ischemia of heart was initiated by stopping the coronary flow for 30 min, followed by 60 min of reperfusion (14 ml min-1. Wistar rats were divided into three groups. The treated group received pomiferin (5 mg/kg/day in 0.5% Avicel; the placebo group received only 0.5% Avicel; the intact group was left without any applications. Biochemical indicators of oxidative damage, lipid peroxidation product malondialdehyde, antioxidant enzymes (superoxide dismutase, glutathione peroxidase, total antioxidant activity in serum and myocardium has been evaluated. We also examined the effect of pomiferin on cardiac function (left ventricular end-diastolic pressure, left ventricular pressure, peak positive +dP/dt (rate of pressure development after ischemia and reperfusion. Our results demonstrate that pomiferin attenuates the myocardial dysfunction provoked by ischemiareperfusion. This was confirmed by the increase in both the antioxidant enzyme values and the total antioxidant activity. The cardio-protection provided by pomiferin treatment results from the suppression of oxidative stress and correlates with the improved ventricular function.

  18. Current knowledge in Polypodium leucotomos effect on skin protection.

    Science.gov (United States)

    Palomino, Olga María

    2015-04-01

    This article provides an overview of pharmacology, toxicity, pharmacokinetics and clinical data of Polypodium leucotomos L. (PL). PL aerial part has proven to exert antioxidant, photoprotective and immunomodulatory activities; its mechanism of action is complex and includes several activities: (1) PL diminishes the production of reactive oxygen and nitrogen species (ROS, RNS); (2) PL inhibits the photoisomerization of trans-urocanic acid (t-UCA); (3) PL inhibits apoptosis induced by ultraviolet radiation; (4) PL prevents damage to genetic material and (5) PL enhances DNA repair. PL is not mutagenic and does not induce acute or chronic toxicity. Its biological effects have been proved in cell cultures, animal models, murine models and in human beings. Photoprotective activity has been assessed in healthy volunteers as well as in patients suffering from several cutaneous diseases such as vitiligo, psoriasis, idiopathic photodermatosis or melasma. PL results to be an efficient treatment especially for sensitive cutaneous phototypes and adds extra protection when ultraviolet radiation (UVR) exposure cannot be avoided, such as wide or narrow band UVB phototherapy or treatment with psoralens plus UVA exposure radiation.

  19. Protective Effects of Edaravone against Methamphetamine-Induced cardiotoxicity

    Directory of Open Access Journals (Sweden)

    Motahareh Koohsari

    Full Text Available ABSTRACT Methamphetamine (METH is widely abused in worldwide. METH use could damage the dopaminergic system and induce cardiotoxicity via oxidative stress and mitochondrial dysfunction. Edaravone, a sedative-hypnotic agent, is known for it's antioxidant properties. In this study we used edaravone for attenuating of METH-induced cardiotoxicity in rats. The groups (six rats in each group were as follows: control, METH (5 mg/kg IP and edaravone (5, 10 and 20 mg/kg, IP was administered 30 min before METH. After 24 hours, animals were killed, heart tissue was separated and mitochondrial fraction was isolated and oxidative stress markers were measured. Edaravone significantly (p<0.05 protected the heart against lipid peroxidation by inhibition of reactive oxygen species (ROS formation. Edaravone also significantly (p<0.05 increased the levels of heart glutathione (GSH. METH administration significantly (p<0.05 disrupted mitochondrial function that edaravone pre-treatment significantly (p<0.05 inhibited METH-induced mitochondrial dysfunction. Protein carbonyl level also increased after METH exposure, but was significantly (p<0.05 decreased with edaravone pre-treatment. These results suggested that edaravone is able to inhibition of METH-induced oxidative stress and mitochondrial dysfunction and subsequently METH-induced cardiotoxicity. Therefore, the effectiveness of this antioxidant should be evaluated for the treatment of METH toxicity and cardio degenerative disease.

  20. Radiation protection standards: a summary of the biological effects of ionising radiation and principles of radiation protection

    International Nuclear Information System (INIS)

    1994-01-01

    This leaflet in the NRPB At-a-Glance-Series briefly summarises the biological effects of radiation, harm and sensitivity to radiation, radiation protection principles, acceptability of risk and the control of doses to workers, the public and in medical procedures in the UK. (UK)

  1. Effect of Dehydroepiandrosterone Sulfate Administration on the Levels of Thyroid Hormones and Testosterone in the γ-Irradiated Rat

    International Nuclear Information System (INIS)

    El-Seifi, S.A.; Abou-Safi, H.M.; Abdel-Hamid, G.R.

    2015-01-01

    Dehydroepiandrosterone Sulfate (DHEAS) is an adrenal hormone and is the most abundant circulatory steroid hormone in the body. This study intended to determine the role of exogenous DHEAS administration (20 mg/100 g b.wt.) and its possible protective and/or mitigating effect (s) against γ- irradiation (6 Gy) induced disorders in the irradiated rats. Five groups of male Albino rats were used. Samples were collected after one day, one week and two weeks post irradiation and/or DHEAS treatment. The levels of thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), testosterone (T) and acid phosphatase (ACP) enzyme activity were measured in plasma, reduced glutathione (GSH) content and thiobarbituric acid reactive species (TBARS) were estimated in testicular tissue. Obtained results showed that DHEAS administration pre-irradiation improved the disturbances induced by irradiation on the tested parameters: TSH, T3, T4, T and ACP. It also elevated reduced GSH level and decreased lipid peroxidation in the testicular tissue. DHEAS treatment pre-irradiation, rather than post-irradiation, exerts a prophylactic effect, by protecting the cellular vital components from ROS, generated by gamma radiation

  2. [Optimizing staff radiation protection in radiology by minimizing the effective dose].

    Science.gov (United States)

    von Boetticher, H; Lachmund, J; Hoffmann, W; Luska, G

    2006-03-01

    In the present study the optimization of radiation protection devices is achieved by minimizing the effective dose of the staff members since the stochastic radiation effects correlate to the effective dose. Radiation exposure dosimetry was performed with TLD measurements using one Alderson Phantom in the patient position and a second phantom in the typical position of the personnel. Various types of protective clothing as well as fixed shields were considered in the calculations. It was shown that the doses of the unshielded organs (thyroid, parts of the active bone marrow) contribute significantly to the effective dose of the staff. Therefore, there is no linear relationship between the shielding factors for protective garments and the effective dose. An additional thyroid protection collar reduces the effective dose by a factor of 1.7 - 3.0. X-ray protective clothing with a 0.35 mm lead equivalent and an additional thyroid protection collar provides better protection against radiation than an apron with a 0.5 mm lead equivalent but no collar. The use of thyroid protection collars is an effective preventive measure against exceeding occupational organ dose limits, and a thyroid shield also considerably reduces the effective dose. Therefore, thyroid protection collars should be a required component of anti-X protection.

  3. Determining localized anode condition to maintain effective corrosion protection.

    Science.gov (United States)

    2010-01-01

    Thermal sprayed zinc anodes used for impressed current cathodic protection of reinforced concrete deteriorate over time. : Two different technologies, ultrasound and electrical circuit resistance combined with water permeability, were : investigated ...

  4. Effectiveness of ultraviolet light personal protective equipment used ...

    African Journals Online (AJOL)

    Journal of Agriculture, Science and Technology ... (UV) light personal protective equipment (PPE) used by arc welders in the informal sector. ... all had formal education: 31.1% had primary school level as the highest attained education level, ...

  5. Oxide layers for silicon detector protection against enviroment effects

    International Nuclear Information System (INIS)

    Bel'tsazh, E.; Brylovska, I.; Valerian, M.

    1986-01-01

    It is shown that for protection of silicon detectors of nuclear radiations oxide layers could be used. The layers are produced by electrochemical oxidation of silicon surface with the following low-temperature annealing. These layers have characteristics similar to those for oxide layers produced by treatment of silicon samples at elevated temperature in oxygen flow. To determine properties of oxide layers produced by electrochemical oxidation the α-particle back-scattering method and the method of volt-farad characteristics were used. Protection properties of such layers were checked on the surface-barrier detectors. It was shown that protection properties of such detectors were conserved during long storage at room temperature and during their storage under wet-bulb temperature. Detectors without protection layer have worsened their characteristics

  6. Lactational Vitamin E Protects Against the Histotoxic Effects of ...

    African Journals Online (AJOL)

    olayemitoyin

    Summary: The work investigated the protective role of lactational vitamin E administration on vanadium-induced histotoxicity. ... includes vitamin C, glutathione, selenium, and .... Int. J. Cancer: 120: 13-23. ... Vanadium (IV) mediated free radical.

  7. Protective effect of WR-2823 in irradiated mice

    International Nuclear Information System (INIS)

    Milovanovicj, A.; Tanasijevicj, D.; Cvetkovicj, M.; Cjosicj, M.; Chizmicj, Z.

    1987-01-01

    A chemical compound named WR-2823 has been synthetised. The acute toxicity after IP application has been investigated and LD 50 estimated. The protective ability of the radioprotector has been investigated in mice with gamma rays of 60 Co, or at the origin of 252 Cf. High protective potency in mice, treated with lethal doses of gamma rays and neutrons have been estimated. (author) 8 refs.; 1 tab

  8. Effective protection of biological membranes against photo-oxidative damage: Polymeric antioxidant forming a protecting shield over the membrane.

    Science.gov (United States)

    Mertins, Omar; Mathews, Patrick D; Gomide, Andreza B; Baptista, Mauricio S; Itri, Rosangela

    2015-10-01

    We have prepared a chitosan polymer modified with gallic acid in order to develop an efficient protection strategy biological membranes against photodamage. Lipid bilayers were challenged with photoinduced damage by photosensitization with methylene blue, which usually causes formation of hydroperoxides, increasing area per lipid, and afterwards allowing leakage of internal materials. The damage was delayed by a solution of gallic acid in a concentration dependent manner, but further suppressed by the polymer at very low concentrations. The membrane of giant unilamellar vesicles was covered with this modified macromolecule leading to a powerful shield against singlet oxygen and thus effectively protecting the lipid membrane from oxidative stress. The results have proven the discovery of a promising strategy for photo protection of biological membranes. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Modulator Effect of Turmeric on Oxidative Damage in Whole Body Gamma Irradiated rats

    International Nuclear Information System (INIS)

    Amin, H.H.; Abdou, M.I.

    2012-01-01

    Because of its penetrating power and its ability to travel great distances, gamma rays are considered the primary hazard to the population during most radiological emergencies. So, there is a need to develop medical countermeasures to protect the first responders and remediation workers from biomedical effect of ionizing radiation. Turmeric has been reported to have many beneficial health effects, including a strong anti-oxidant effect, anti-inflammatory and anti-microbial properties. In the present study, turmeric was investigated as a therapeutic agent against hazards induced by ionizing radiation on kidney, liver, urinary and serum calcium levels and blood counts. A daily dose of 0.5 g/kg body weight was used in whole body gamma irradiated female rats with 3 Gy. Radiation effects were followed up for four weeks post irradiation. The results revealed that the administration of turmeric post-irradiation resulted in a significant inhibition in the frequency of radiation induced oxidative damage. It could be concluded that definite turmeric dose exerts a vital modulator role against gamma irradiation hazard

  10. Ionizing radiation biological effects and the proper protective measures against it's harmful effects

    International Nuclear Information System (INIS)

    Hhalel, A.M.

    1990-01-01

    This book intrduces a good knowledge in specifications of ionizing radiation biological effects and the proper protective measures againest harmful effectes. The book is devided in to five main sections, the first one introduces the hostorical bachground of the contributions of a number of scietists in the basic knolwledge of radiation and its biological effects. The second section deals with the physical and chemical principles of radiation the third one talks about radiation detection. While the fourth section talks (via seven chapter) about the effectes of ionizing radiation on living organisms molecules cells, tissues organs systems and the living organism the fifth section talks about the uses of radiation sources, the probability of radiation accidents, protective measures, international recommendations related to doses and safe use of ionizing radiation. (Abed Al-wali Al-ajlouni). 53 refs., 107 figs., 13 tabs

  11. Illustration of distributed generation effects on protection system coordination

    Science.gov (United States)

    Alawami, Hussain Adnan

    Environmental concerns, market forces, and emergence of new technologies have recently resulted in restructuring electric utility from vertically integrated networks to competitive deregulated entities. Distributed generation (DG) is playing a major role in such deregulated markets. When they are installed in small amounts and small sizes, their impacts on the system may be negligible. When their penetration levels increase as well as their sizes, however, they may start affecting the system performance from more than one aspect. Power system protection needs to be re-assessed after the emergence of DG. This thesis attempts to illustrate the impact of DG on the power system protection coordination. It will study the operation of the impedance relays, fuses, reclosers and overcurrent relays when a DG is added to the distribution network. Different DG sizes, distances from the network and locations within the distribution system will be considered. Power system protection coordination is very sensitive to the DG size where it is not for the DG distance. DG location has direct impact on the operation of the protective devices especially when it is inserted in the middle point of the distribution system. Key Words, Distributed Generation, Impedance relay, fuses, reclosers, overcurrent relays, power system protection coordination.

  12. Multilayer graphene as an effective corrosion protection coating for copper

    Science.gov (United States)

    Ravishankar, Vasumathy; Ramaprabhu, S.; Jaiswal, Manu

    2018-04-01

    Graphene grown by chemical vapor deposition (CVD) has been studied as a protective layer against corrosion of copper. The layer number dependence on the protective nature of graphene has been investigated using techniques such as Tafel analysis and Electroimpedance Spectroscopy. Multiple layers of graphene were achieved by wet transfer above CVD grown graphene. Though this might cause grain boundaries, the sites where corrosion is initiated, to be staggered, wet transfer inherently carries the disadvantage of tearing of graphene, as confirmed by Raman spectroscopy measurements. However, Electroimpedance Spectroscopy (EIS) reflects that graphene protected copper has a layer dependent resistance to corrosion. Decrease in corrosion current (Icorr) for graphene protected copper is presented. There is only small dependence of corrosion current on the layer number, Tafel plots clearly indicate passivation in the presence of graphene, whether it be single layer or multiple layers. Notwithstanding the crystallite size, defect free layers of graphene with staggered grain boundaries combined with passivation could offer good corrosion protection for metals.

  13. Use and effect of X-ray protective clothing

    International Nuclear Information System (INIS)

    Rothe, W.

    1976-01-01

    The use of X-ray protective clothing in direct handling the patient was studied in 76 X-ray departments. Mainly two types of lead rubber aprons are used, older ones with a lead equivalent of 0.2 mm and aprons according to TGL 200-1606 with a lead equivalent of 0.25 mm. Aprons are not yet worn in all surgical departments. Their replacement by protective skirts is to be refused. If at all, lead rubber gloves are only used in standardized fluoroscopic examinations, especially in examining the gastrointestinal tract. It is emphasized that only the protected fore-part is to be directed to the main radiation source, especially in seating or leaning forward positions. (author)

  14. Effectiveness of Protected Areas for Representing Species and Populations of Terrestrial Mammals in Costa Rica

    Science.gov (United States)

    González-Maya, José F.; Víquez-R, Luis R.; Belant, Jerrold L.; Ceballos, Gerardo

    2015-01-01

    Costa Rica has one of the greatest percentages (26%) of protected land in the world. The National Protected Areas System (NPAS) of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species’ geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5%) in protected areas, but low relative coverage (28.3% on average) of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection. PMID:25970293

  15. Effectiveness of protected areas for representing species and populations of terrestrial mammals in Costa Rica.

    Directory of Open Access Journals (Sweden)

    José F González-Maya

    Full Text Available Costa Rica has one of the greatest percentages (26% of protected land in the world. The National Protected Areas System (NPAS of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species' geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5% in protected areas, but low relative coverage (28.3% on average of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection.

  16. Herd protection effect of N95 respirators in healthcare workers.

    Science.gov (United States)

    Chen, Xin; Chughtai, Abrar Ahmad; MacIntyre, Chandini Raina

    2017-12-01

    Objective To determine if there was herd protection conferred to unprotected healthcare workers (HCWs) by N95 respirators worn by colleagues. Methods Data were analysed from a prospective cluster randomized clinical trial conducted in Beijing, China between 1 December 2008 and 15 January 2009. A minimum compliance level (MCL) of N95 respirators for prevention of clinical respiratory illness (CRI) was set based on various compliance cut-offs. The CRI rates were compared between compliant (≥MCL) and non-compliant (protection from use of N95 respirators by colleagues within a hospital ward.

  17. Effects of the communities that care prevention system on youth reports of protective factors.

    Science.gov (United States)

    Kim, B K Elizabeth; Gloppen, Kari M; Rhew, Isaac C; Oesterle, Sabrina; Hawkins, J David

    2015-07-01

    Many interventions seeking to reduce problem behaviors and promote healthy youth development target both risk and protective factors, yet few studies have examined the effect of preventive interventions on overall levels of protection community wide. In a community-randomized controlled trial, this study tested the effect of Communities That Care (CTC) on protective factors in 24 communities across seven states. Data on protective factors were collected from a panel of 4407 youths in CTC and control communities followed from grade 5 through grade 8. Hierarchical linear modeling compared mean levels of 15 protective factors derived from the social development model in CTC and control communities in grade 8, adjusted for individual and community characteristics and baseline levels of protective factors in grade 5. Global test statistics were calculated to examine effects on protection overall and by domain. Analyses across all protective factors found significantly higher levels of overall protection in CTC compared to control communities. Analyses by domain found significantly higher levels of protection in CTC than control communities in the community, school, and peer/individual domains, but not in the family domain. Significantly higher levels of opportunities for prosocial involvement in the community, recognition for prosocial involvement in school, interaction with prosocial peers, and social skills among CTC compared to control youth contributed to the overall and domain-specific results. This is consistent with CTC's theory of change, which posits that strengthening protective factors is a mechanism through which CTC prevents behavior problems.

  18. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  19. TOXIC EFFECTS OF CHLOROPICRIN AND IMPACT OF SORBED WATER STEAM ON PROTECTION

    Directory of Open Access Journals (Sweden)

    Milena Nikolić

    2013-01-01

    Full Text Available Chloropicrin is a chemical substance that has a very toxic effect. Exerts its effect on the respiratory system. Causes pulmonary edema and difficult breathing and suffocating effect. Respiratory protection may be carried into execution respiratory filters. On the protective power filter based on active coal affects adsorbed water vapor. This paper presents the results of the adsorption of water vapor on activated carbon from 5% to 25%. Was used for the experiment apparatus for dynamic adsorption, the results showed that the humidity of 5% coal provides most power protection, while humidity of 25% minimum protective power.

  20. Developing effective rockfall protection barriers for low energy impacts

    Science.gov (United States)

    Mentani, Alessio; Giacomini, Anna; Buzzi, Olivier; Govoni, Laura; Gottardi, Guido; Fityus, Stephen

    2016-04-01

    Recently, important progresses have been made towards the development of high capacity rockfall barriers (100 kJ - 8000 kJ). The interest of researchers and practitioners is now turning to the development of fences of minor capacity, whose use becomes essential in areas where rockfall events generally have low intensity and the use of high capacity barriers would be accompanied by excessive costs and high environmental impact. Low energy barriers can also provide a cost-effective solution even in areas where high energies events are expected. Results of full-scale tests are vital to any investigation on the behaviour of these structures. An experimental set-up has been developed at The University of Newcastle (AUS), to investigate the response of low energy rockfall barrier prototypes to low energy impacts. The Australian territory, and in particular New South Wales, is in fact characterised by rockfall events of low-to-medium intensity (50 kJ - 500 kJ) and the need of protection structures working within such energy range, is particularly felt [1]. The experiments involved the impact of a test block onto three spans, low energy barrier prototypes, made of steel structural posts, fully fixed at the base, side cables and a steel meshwork constituted by a double twist hexagonal wire net [2]. Test data enabled the development, calibration and assessment of FE models [3], on which non-linear and dynamic analyses have been performed addressing the effect of the block size. Results have shown that the response of the structure is strongly governed by the net. Data from tests conducted on the sole net and on the entire barrier showed in fact a similar trend, different to what typically observed for high capacity barriers, whose behaviour is also led by the presence of uphill cables and brakes. In particular, the numerical analyses have demonstrated a dependence of the net performance on the block size. In particular, a loss of capacity in the order of 50% occurred as the

  1. Design, irradiation, and post-irradiation examination of the UC and (U,Pu)C fuel rods of the test groups Mol-11/K1 and Mol-11/K2

    International Nuclear Information System (INIS)

    Freund, D.; Elbel, H.; Steiner, H.

    1976-06-01

    The test groups K1 and K2 of the irradiation experiment Mol-11 are reported. Design, irradiation, and post-irradiation examination of the fuel rods irradiated are described. Mol-11/K1 consisted of one fuel rod with UC of 94% T.D. and helium bonding. This test group was intended to prove the high power irradiation capsule in pile. Mol-11/K2 consists of three fuel rods in total. One of these is presently still in the reactor. In this test group mixed carbide fuel of 83% T.D. and 15% Pu content under helium bonding is irradiated. The fuel rod K2-2 was provided with a capillary tube for the continuous measurement of fission gas pressure built up. 1.4988 stainless steel was chosen as cladding material. The final burnup lies between 35 and 70 MWd/kg M. Post-irradiation examination of the two test groups covers a theoretical analysis of the irradiation behaviour. (orig./GSCH) [de

  2. Protective effects of cistanches herba aqueous extract on cisplatin ...

    African Journals Online (AJOL)

    Background: Chemotherapeutic treatment of premenopausal women has been linked to premature ovarian failure (POF). Cistanches Herba (CH) is a commonly used male impotence and female infertility treatment in China; however, whether CH protects ovaries from chemotherapeutic drug-induced POF remains unclear.

  3. Effect of ectomycorrhizal fungi in the protection of Uapaca kirkiana ...

    African Journals Online (AJOL)

    Investigations carried out on the use of ectomycorhhizal fungi in the management of Uapaca kirkiana root diseases caused by three pathogens (Rhizoctonia solani, Phytophthora parasitica and Pseudomonas solani) revealed that different mycorrhizal fungi vary in their ability to protect roots against these respective ...

  4. Ship Inspection Strategies: Effects on Maritime Safety and Environmental Protection

    NARCIS (Netherlands)

    C. Heij (Christiaan); G.E. Bijwaard (Govert); S. Knapp (Sabine)

    2010-01-01

    textabstractGlobal trade depends for a large part on maritime transport, and safe ships are needed not only to protect precious cargo but also to prevent environmental damage. Flag state and port state authorities spend much effort in ship safety inspections to ensure a minimum safety level and to

  5. Ship inspection strategies: effects on maritime safety and environmental protection

    NARCIS (Netherlands)

    Heij, C.; Bijwaard, G.E.; Knapp, S.

    2011-01-01

    Global trade largely depends on maritime transport, and appropriate ships are needed to protect cargo but to minimize environmental damage and to this end, flag and port state authorities expend considerable effort in ship safety inspections. This paper investigates the safety gains of current

  6. Assessment of the protective effect of male circumcision from HIV ...

    African Journals Online (AJOL)

    East African Journal of Public Health ... A cross-sectional comparative study based on secondary data of 18 Demographic Health Surveys (DHS) carried out in Sub-Saharan Africa starting from 2003 was conducted to assess the protective ... Adjustment was made for sexual history and basic socio-demographic variables.

  7. Protective Effects of Dimedone Pyrone on Podocytes in Rats with ...

    African Journals Online (AJOL)

    improvements while nephrin and podocin protein expression levels were significantly higher in the nephridial tissue. Decrease in relative kidney ... therapeutic importance in the treatment of diabetic nephropathy. Keywords: Dimedone pyrone ..... Brown WV. Microvascular complications of diabetes mellitus: renal protection ...

  8. Protective effects of aqueous extract of Telfairia occidentalis on ...

    African Journals Online (AJOL)

    Mercury intoxication in rodents causes damage to various organs including the brain via oxidative stress. Aqueous extract of Telfairia occidentalis (TOAE) may be a preventive agent by virtue of its reported antioxidant property. The present study was carried out to investigate the possible protective role of TOAE against ...

  9. Protective effect of salvianolic acid B against intestinal ischemia ...

    African Journals Online (AJOL)

    Conclusion: The results of this study demonstrate that SAB may protect the intestine by attenuating oxidative stress and inflammatory response and hence, may be potentially for treating IIRI. Keywords: Salvianolic acid B, Intestinal Ischemia-reperfusion, Antioxidants, Inflammation, Intestinal permeability ...

  10. Early stage beneficial effects of cathodic protection in concrete structures

    NARCIS (Netherlands)

    Polder, R.B.; Peelen, W.H.A.; Neeft, E.A.C.; Stoop, B.T.J.

    2010-01-01

    Over the last 25 years, cathodic protection (CP) of reinforced concrete structures suffering from chloride induced reinforcement corrosion has shown to be successful and durable. CP current causes steel polarisation, electrochemical reactions and ion transport in the concrete. CP systems are

  11. Protective effects of Punica granatum seeds extract against aging ...

    African Journals Online (AJOL)

    Punica granatum extract also significantly lowered lipid peroxidation level and increased antioxidant glutathione level in brain tissues. Punica granatum preparations could be protective in the treatment of cognitive disorders such as dementia and Alzheimer's disease. Key words: Punica granatum, Cognitive deficits, Vitamin ...

  12. Radiation Effects on PP/PS Blends as a Model of Protection Effects by Aromatics

    International Nuclear Information System (INIS)

    Gluszewski, W.

    2006-01-01

    Polypropylene (PP) is the most popular polymer for the application in construction of medical devices, due to the hardness and temperature resistance. Unfortunately, the virgin PP is of low resistance towards ionizing radiation, already to sterilization doses and cannot be applied without additives. Another option is a blend with a second polymer, especially aromatic, and therefore polystyrene (PS) was applied. The classic case of protection in the aliphatic/aromatic system (benzene/cyclohexane in liquid or solid state) shows that the surface area and structure of the interphase is crucial for the effectiveness of energy transfer. Our blends of PP (virgin, F401 from Orlen-Olefins) with PS were prepared in a variety of ways, from mechanical blending, to radiation induced grafting. Two linac accelerators (10 MeV, 6-9 kW) were applied, with different shapes of electron beam, formed according to particular methods used for the investigation of effects; doses were 10-600 kGy. As in the classic case, the protection effect was quantisized from the curve of the effect vs 0-100% PP, 100-0 % PS. Main recognition of the protection effect has been done by the diffused reflection spectroscopy (DRS) developed in our Laboratory for the application to irradiated polymers. The dependence of intensity of bands in the DRS spectrum, attributed to keton groups, which are final products of oxidation, shows clearly the protection effect of PP, executed by PS. The second method of observation of radiation effects is gas chromatography (GC), applied for irradiation products analysis. The maximum sensitivity has been achieved using the instrument type GC 2014 by Shimadzu, with thermal conductivity detector, column packed with molecular sieves 5A. Radiation induced formation of gaseous produced at ambient and lower temperatures is unique in the field of chemistry of polymers. There is no form of energy, except ionizing radiation, to cause chemical reactions to produce a wide spectrum of low

  13. Linking management effectiveness indicators to observed effects of protected areas on fire occurrence in the Amazon rainforest.

    Science.gov (United States)

    Nolte, Christoph; Agrawal, Arun

    2013-02-01

    Management-effectiveness scores are used widely by donors and implementers of conservation projects to prioritize, track, and evaluate investments in protected areas. However, there is little evidence that these scores actually reflect the capacity of protected areas to deliver conservation outcomes. We examined the relation between indicators of management effectiveness in protected areas and the effectiveness of protected areas in reducing fire occurrence in the Amazon rainforest. We used data collected with the Management Effectiveness Tracking Tool (METT) scorecard, adopted by some of the world's largest conservation organizations to track management characteristics believed to be crucial for protected-area effectiveness. We used the occurrence of forest fires from 2000 through 2010 as a measure of the effect of protected areas on undesired land-cover change in the Amazon basin. We used matching to compare the estimated effect of protected areas with low versus high METT scores on fire occurrence. We also estimated effects of individual protected areas on fire occurrence and explored the relation between these effects and METT scores. The relations between METT scores and effects of protected areas on fire occurrence were weak. Protected areas with higher METT scores in 2005 did not seem to have performed better than protected areas with lower METT scores at reducing fire occurrence over the last 10 years. Further research into the relations between management-effectiveness indicators and conservation outcomes in protected areas seems necessary, and our results show that the careful application of matching methods can be a suitable method for that purpose. ©2012 Society for Conservation Biology.

  14. Strengthening Radiation Protection Infrastructures in Africa: Towards Establishing Effective and Sustainable Co-operations and Networks

    International Nuclear Information System (INIS)

    2010-09-01

    The third African IRPA 2010 conference on Strengthening Radiation Protection Infrastructures in Africa: Towards Establishing Effective and Sustainable Co-operations and Networks. IAEA's role in radiation protection with focus in Africa. The controlling of exposure to indoor Radon. And Measure of activities and calculation of effective dose of indoor 222 Rn in some dwelling and enclosed areas in Africa - capacity building for radiation protection. It had also address Patient Radiation Protection in Radiotherapy, challenges for advancing medical physic globally, Heath effects and medical applications of non-ionizing radiation, nuclear safety and radiation protection consideration in the design of research and development. The International radiation protection association (IRPA) 2010-2011 strategic plan that address among other issues educations and training activities (2000-2020) and the current UNSCLEAR activities

  15. Ultraviolet-B-effects on plants: Spectra of harmful effects, primary damage and UV protective mechanisms

    International Nuclear Information System (INIS)

    Wellmann, E.; Beggs, C.; Moehle, B.; Schneider-Ziebert, U.; Steinmetz, V.; Koch, U.

    1986-01-01

    In two model systems of higher plants, damage caused by ultraviolet-B-radiation was analysed as to its mechanism of action and the spectral quantum efficiency. These investigations were to provide information on the relevance of such UV effects in cases of increased ultraviolet-B-irradiation owing to the destruction of ozone. The results indicate the very high tolerance of the plants to ultraviolet-B-radiation which obviously is the result of very effective protective mechanisms, and show at the same time that potential damage must already be reckoned with, given the current share of ultraviolet-B-radiation in solar radiation. Should ultraviolet-B-radiation be increased, then indirect damage to the plant from the destruction of ultraviolet protective mechanisms through UV-B-radiation will probably constitute a particular risk. (orig./MG) [de

  16. Protection of WWER type primary loops against extreme effects

    International Nuclear Information System (INIS)

    Podrouzek, J.; Rejent, B.

    1985-01-01

    Dynamic analyses of the WWER-440 primary loops for the Mochovce nuclear power plant showed that the unprotected primary loop is very soft with a first eigenfrequency of 0.38 Hz. Protection with amortisseurs and viscous shock absorbers was compared and the viscous shock absorber in all cases proved to be more suitable. GERB viscous absorbers will be installed at the Mochovce nuclear power plant. First calculations of the dynamic resistance of the WWER-1000 primary loops for the Temelin nuclear power plant to extreme events were also made. It was shown that the unprotected primary loop is rather soft with a first eigenfrequency of 0.9 Hz, or 0.6 Hz at the pressurizer branch. It will therefore be necessary to protect the primary loops with viscous shock absorbers. (Z.M.)

  17. Effective legal protection in the licensing of technical installations

    International Nuclear Information System (INIS)

    Froehler, L.

    1987-01-01

    Undeterminate concepts of law shall match the dynamism of technical progress in licensing technical installations (e.g. section 7, para. 2 no. 3 Atomic Energy Act). The administration and the courts have the duty to equalize normative deficits of regulation. Decrees and administrative provisions have an important impact. Administrative courts shall exercise legal protection more efficiently what e.g. can be possible after a shortening of stages of appeal. (CW) [de

  18. Effective construction of environmental protection agreements; Wirksame Gestaltung von Umweltschutzabkommen

    Energy Technology Data Exchange (ETDEWEB)

    French, H.F. [Worldwatch Inst., Washington, DC (United States)

    1995-02-01

    By now 170 international agreements are designed to protect air, ground, water and organisms from man-made hazards. Nevertheless are innovative approaches required for global conventions to make the Earth a sanctuary of life for good. (orig.) [Deutsch] Schon mehr als 170 internationale Vertraege sollen Luft, Boden, Wasser und die Organismen vor Gefaehrdungen durch den Menschen bewahren. Gleichwohl sind innovative Ansaetze fuer globale Vereinbarungen erforderlich, damit die Erde auf Dauer ein sicherer Hort des Lebens ist. (orig.)

  19. The polarising processes by cathodic protection and their effects

    Directory of Open Access Journals (Sweden)

    Vu¾cha Ján

    2004-09-01

    Full Text Available For the determination of appropriate protection against the corrosion of metal materials it is necessary to understand in details the principle of the corrosion. The corrosion is the oxidation of metal material which results in the change of its chemical composition. This chemical change is greatly influenced by the electrical current flowing in metal depending on electrical current flowing direction and intensity.

  20. E.S.R. studies of mechanisms of radiation protection effect by cysteine and cystine

    International Nuclear Information System (INIS)

    Xue-Peng, L.; Tie-Cheng, T.; Nian-Yun, L.

    1981-01-01

    By means of E.S.R. the repair mechanism of radiation induced spin transfer from dTMP to cysteine in binary system dTMP-cysteine has been confirmed. Furthermore, a new marked radiation protection effect, exerted by cysteine or cystine on thymine irradiated and observed at low temperature, has been detected. Another sort of fast protection mechanism, including electron transfer and excitation transfer, has been proposed, based on recent advances of primary radiation process of pyrimidine bases and analysed by molecular orbital theory. This fast radiation protection mechanism provides the possibility to utilize electrophilic sulfhydryl protectors for realizing excellent protection effect. (author)

  1. ESSAY ON THE EFFECTIVENESS OF THE COLLECTIVE PROTECTION IN PORTUGAL

    Directory of Open Access Journals (Sweden)

    Luciano Picoli Gagno

    2017-08-01

    Full Text Available This essay aims to examine certain aspects concerning collective judicial process by the light of some Portuguese cases, having as base the collective judicial protection understood as a fundamental right. With regard to the employed research method, the approach is the qualitative one, while the method is the deductive and the technique is the bibliographic e jurisprudential research. The theoretical framework is based on the doctrine and theory of some of the cited authors during the research. Among them are Robert Alexy, Mauro Cappelletti and Bryant Garth. In addition, this paper is divided into three sections: the first one is a brief study on access to justice clarified as a fundamental right of the citizen. In the second section a parallel is made with the first one, but the collective judicial protection is therefore seen as a fundamental right. In the third and last section we have the analysis of four cases of two superior courts of Portugal, being them the Supreme Court of Justice (STJ and the Supreme Administrative Court (STA, in order to understand the collective process in Portugal and to see which points that can offer a contribution for the brazilian collective procedural technic. As a result, it is found that collective judicial protection is inevitable and immanent for a substantial vision of the fundamental right of access to justice, understood like a orders of optimization, that may his realization in the biggest measure is possible

  2. Measuring impact of protected area management interventions: current and future use of the Global Database of Protected Area Management Effectiveness.

    Science.gov (United States)

    Coad, Lauren; Leverington, Fiona; Knights, Kathryn; Geldmann, Jonas; Eassom, April; Kapos, Valerie; Kingston, Naomi; de Lima, Marcelo; Zamora, Camilo; Cuardros, Ivon; Nolte, Christoph; Burgess, Neil D; Hockings, Marc

    2015-11-05

    Protected areas (PAs) are at the forefront of conservation efforts, and yet despite considerable progress towards the global target of having 17% of the world's land area within protected areas by 2020, biodiversity continues to decline. The discrepancy between increasing PA coverage and negative biodiversity trends has resulted in renewed efforts to enhance PA effectiveness. The global conservation community has conducted thousands of assessments of protected area management effectiveness (PAME), and interest in the use of these data to help measure the conservation impact of PA management interventions is high. Here, we summarize the status of PAME assessment, review the published evidence for a link between PAME assessment results and the conservation impacts of PAs, and discuss the limitations and future use of PAME data in measuring the impact of PA management interventions on conservation outcomes. We conclude that PAME data, while designed as a tool for local adaptive management, may also help to provide insights into the impact of PA management interventions from the local-to-global scale. However, the subjective and ordinal characteristics of the data present significant limitations for their application in rigorous scientific impact evaluations, a problem that should be recognized and mitigated where possible. © 2015 The Authors.

  3. Impact of vaccine herd-protection effects in cost-effectiveness analyses of childhood vaccinations. A quantitative comparative analysis.

    Science.gov (United States)

    Holubar, Marisa; Stavroulakis, Maria Christina; Maldonado, Yvonne; Ioannidis, John P A; Contopoulos-Ioannidis, Despina

    2017-01-01

    Inclusion of vaccine herd-protection effects in cost-effectiveness analyses (CEAs) can impact the CEAs-conclusions. However, empirical epidemiologic data on the size of herd-protection effects from original studies are limited. We performed a quantitative comparative analysis of the impact of herd-protection effects in CEAs for four childhood vaccinations (pneumococcal, meningococcal, rotavirus and influenza). We considered CEAs reporting incremental-cost-effectiveness-ratios (ICERs) (per quality-adjusted-life-years [QALY] gained; per life-years [LY] gained or per disability-adjusted-life-years [DALY] avoided), both with and without herd protection, while keeping all other model parameters stable. We calculated the size of the ICER-differences without vs with-herd-protection and estimated how often inclusion of herd-protection led to crossing of the cost-effectiveness threshold (of an assumed societal-willingness-to-pay) of $50,000 for more-developed countries or X3GDP/capita (WHO-threshold) for less-developed countries. We identified 35 CEA studies (20 pneumococcal, 4 meningococcal, 8 rotavirus and 3 influenza vaccines) with 99 ICER-analyses (55 per-QALY, 27 per-LY and 17 per-DALY). The median ICER-absolute differences per QALY, LY and DALY (without minus with herd-protection) were $15,620 (IQR: $877 to $48,376); $54,871 (IQR: $787 to $115,026) and $49 (IQR: $15 to $1,636) respectively. When the target-vaccination strategy was not cost-saving without herd-protection, inclusion of herd-protection always resulted in more favorable results. In CEAs that had ICERs above the cost-effectiveness threshold without herd-protection, inclusion of herd-protection led to crossing of that threshold in 45% of the cases. This impacted only CEAs for more developed countries, as all but one CEAs for less developed countries had ICERs below the WHO-cost-effectiveness threshold even without herd-protection. In several analyses, recommendation for the adoption of the target

  4. Ethical considerations in protecting the environment from the effects of ionizing radiation. A report for discussion

    International Nuclear Information System (INIS)

    2002-02-01

    In recent years awareness of the vulnerability of the environment has increased and the need to protect it against the effects of industrial pollutants has been recognized. This trend is reflected in new and developing international policies for environmental protection. In the context of protection of the environment against ionizing radiation, the existing international approach is based on providing for the protection of humans. The current recommendations of the International Commission on Radiological Protection (ICRP) include the statement that t he standard of environmental control needed to protect man to the degree currently thought desirable will ensure that other species are not put at risk... . In the light of the new focus of concern for the environment, this statement is being critically reviewed in several international fora. The IAEA has, over many years, sponsored studies of the effects of ionizing radiation on species other than humans. Most recently it published a discussion report as IAEA-TECDOC-1091 (1999) in which the need for developing a system for protecting the environment against the effects of ionizing radiation was elaborated and in which various related technical and philosophical issues for resolution were discussed. The current report explores the ethical principles that could underlie a system of environmental protection. It is intended as one step in the development of a framework for the protection of the environment from the effects of ionizing radiation, and is being published in order to promote awareness of the current developments in this field as well as to encourage discussion amongst those involved

  5. Effect of irradiation and storage post-irradiation of black pepper (Piper nigrum L.) on counts of microorganisms hygienic indicator using methods of conventional analysis and PETRIFILMTM plates

    International Nuclear Information System (INIS)

    Jaimes, Marcial Ibo Silva

    1988-01-01

    Fifteen samples of ground black pepper (Piper nigrum L.) purchased in Sao Paulo local stores, were submitted to irradiation in doses of 3, 6 and 10 kGy. All irradiated samples, including non-irradiated controls, were submitted to counts of yeasts and molds, aerobes (APC), coliforms and mesophilic aerobic spore formers (MASC), using conventional plate count methods and PETRIFILM TM plates. For yeasts and molds count, acidified potato dextrose agar (PDA) an PETRIFILM TM PFYM plates were used. For aerobes, plate count agar (PCA) and PETRIFILM TM PFAC plates were used. Violet red bile agar (VRBA) and PETRIFILM TM PFEC plates were employed for enumeration of coliforms. Counts of these groups of microorganisms obtained through the traditional plating procedures did not differ significantly from those using the corresponding PETRIFILM TM plates. In samples submitted to irradiation, a dose of 10 kGy caused a decrease of the yeasts and molds count from 10 4 -10 5 to less than 10 cfu/g. The same dose caused a decrease of the aerobic counts from 10 7 -10 8 to 10 2 -10 3 cfu/g, of coliforms from 10 4 -10 5 to less than 10 cfu/g and MASC from 10 6 -10 7 cfu/g to 10-10 2 cfu/g. The introduction of a injury repair step in the counting procedure resulted in a 32 to 89% increase in the number of coliforms. However, this additional step did not improve significantly the counts of MASC. After 270 days of storage of samples irradiated with 3 kGy, a decrease in the yeasts and molds population from 10 3 to 20 cfu/g was observed. The APC population in these samples was reduced from 5,0x10 6 to 2,4x10 4 cfu/g; in those irradiated with 6 kGy the reduction was from 4,0x10 4 to 5,0x10 3 cfu/g and in those irradiated with 10 kGy the counts were reduced from 30 to less than 10 cfu/g. After the same time of storage, the coliform population in non irradiated samples decreased from 2,8x10 5 to 1,5x10 4 cfu/g and from 9,1x10 3 to 20 cfu/g in those irradiated with 3 kGy. Similarly, the MASC decreased from 2,8x10 4 to 5,6x10 3 cfu/g in samples irradiated with 3 kGy and from 1,2x10 4 to 6,6,x10 2 cfu/g in samples irradiated with 6 kGy. (author)

  6. Effect of wound healing period and temperature, irradiation and post-irradiation storage temperature on the rot incidence of potatoes, after infection with Fasurium sulfurium

    NARCIS (Netherlands)

    Langerak, D.I.; Wolters, T.C.; Quan, V.H.; Oularbi, S.; Tayeb, Y.; Vroomen, L.H.M.

    1988-01-01

    Losses during star age in potatoes are mainly due to sprouting and rotting. It has indicated that irradiation by low dose (50 to 100 Gy) during the dormancy period is most e ffective for sprout inhibition. Some investigators, however , stated an increase of storage rot after an irradiation

  7. Theoretical and practical implications of the effects of temperature during irradiation and during pre- and post-irradiation storage on the response of thermoluminescence dosimeters

    International Nuclear Information System (INIS)

    Gail de Planque, E.

    1984-01-01

    Experiments have been conducted to determine the applicability of the Randall-Wilkins theory for describing the behavior of CaF 2 :Mn thermoluminescence dosimeters (Harshaw TLD-400 chips). Results were obtained for four different conditions: irradiation followed by storage, irradiation after storage, irradiation both preceded and followed by storage, and continuous simultaneous irradiation and storage. The experiments were performed for storage intervals of approximately 1, 2, 3, 5, 6 and 7 days at five different storage temperatures: -25, +20, +65, +150 and +175 0 C. The results indicate fading that is described not by the Randall-Wilkins theory but rather as a linear function of the logarithm of the storage time. While the results suggest that the trapping efficiency is independent of temperature, they do demonstrate a small decrease in TL response with storage time prior to irradiation which is independent of temperature and time (>17 hours) and hence probably not dosimetric in origin but perhaps optically related. Glow curve analyses support the concept of a band of traps rather than a single trap. The overall results are compared to other data available in the literature most of which is for room-temperature storage. These data, for storage periods ranging from minutes to one year, can also be described as a linear function of the logarithm of the storage time and are remarkably consistent when uniformly normalized. Although peripheral experiments revealed problems associated with self-irradiation as well as a decline in sensitivity with use, the stability experiment results verify the highly favorable stability properties of CaF 2 :Mn for widespread application

  8. Effect of protective atmosphere on color of goose meat.

    Science.gov (United States)

    Orkusz, A; Woloszyn, J; Haraf, G; Okruszek, A

    2013-08-01

    The objective of the work was to characterize the color of the of the goose breast meat packaged in protective atmosphere and stored in the refrigerated conditions. The aim was realized by determination of total heme pigment concentration; relative concentration of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L* (lightness), a* (redness), and b* (yellowness); and sensory evaluation of the surface color. The experimental material was White Kołuda goose boneless breast meat with the skin from industrial slaughter. The following 2 protective atmospheres were used in the study: vacuum and modified atmosphere (MA) consisting of 80% O2 and 20% CO2. The muscles packed in protective atmosphere were examined on d 4, 7, 11, and 14 of storage. A control sample was goose breast meat stored in air and tested after 24 h after slaughter. The total pigment concentration decreased gradually within 14 d of storage for samples packed in 2 types of atmospheres. The increase in relative concentration of metmyoglobin and the decrease in oxymyoglobin relative concentration in total heme pigments in the meat stored in MA was noticed. However, in all times of storage, the relative concentration of the 3 samples of myoglobin forms stored in vacuum was unchanged. The color parameters (L*, a*, b*) did not change for 14 d of storage in the muscles packed in vacuum. One can state a decrease of the value of the color parameter a* as well as an increase of the value of the color parameter b* in the samples packed in MA. From d 11 to 14 of storage, goose meat packed under MA had lower sensory evaluation intensity of color than muscles under vacuum. The obtained data indicated that the surface color of goose breast meat packed in MA (consisting of 80% O2, 20% CO2) or vacuum packed was maintained for 11 and 14 d, respectively.

  9. The Effect of Operating Lamps on the Protected Area of a Unidirectional Down Flow (UDF) System.

    Science.gov (United States)

    Traversari, A A L; Bottenheft, C; Louman, R; van Heumen, S P M; Böggemann, J

    2017-04-01

    Operating lamps are often seen as the most disruptive factors within the protective area in the operating theater (OT). The effect of the operation lamps (with different shapes) should be demonstrated in an OT by trial, since research on the effects of the lamps is still limited. The main aim of this study was to determine the effects of a skirt, different lamps, and the position of the lamp on the protected area. The concentration of airborne particles was measured under different circumstances, in order to determine the size and quality of the protected area. This entrainment/segregation test is based on the deliberate and controlled emission of particles outside the zone that is protected. The degree of protection (DP) at the center of the protected area was higher for the case with the skirt. This skirt stimulates more down flow and prevents the early entry of particles into the protected area. It can also be concluded that Lamp Y, due to its open shape, has the most positive effect on the DP at the center. It has also been shown that the position of the lamp has an effect on the protected area.

  10. Effect of thermal neutron irradiation on mechanical properties of alloys for HTR core applications

    International Nuclear Information System (INIS)

    Ogawa, Yutaka; Kondo, Tatsuo; Ishimoto, Kiyoshi; Ohtsuka, Tamotsu

    1979-01-01

    An industrial heat of Hastelloy-X containing 2.3 ppm boron was creep-tested at 900 0 C after irradiating thermal neutrons by 6.6 x 10 20 n.cm -2 at temperatures 670 to 880 0 C in JMTR. Significant reduction in rupture life and ductility was observed, and large shift of accelerated deformation stage to short time side was also apparent at comparatively high stresses. Below about 2.2 kg.mm -2 , apparent relief from the degradation was seen. The elongation, however, was found to be due to the formation of numerous intergranular cracks in the premature stage of deformation. Based on the post irradiation tensile properties of several industrial alloys the degree of the ductility loss was found to be nearly dependent on the boron content of the alloys. The post irradiation tensile tests for a special low boron grade heat revealed the means of protecting materials from the effect to be feasible. (author)

  11. Effect of thermal neutron irradiation on mechanical properties of alloys for HTR core applications

    International Nuclear Information System (INIS)

    Ogawa, Yutaka; Kondo, Tatsuo; Ishimoto, Kiyoshi; Ohtsuka, Tamotsu

    1979-02-01

    An industrial heat of Hastelloy-X containing 2.3 ppm boron was creep-tested at 900 0 C after irradiating thermal neutrons by 6.6 x 10 20 n/cm 2 at temperatures 670 to 880 0 C in JMTR. Significant reduction in rupture life and ductility was observed, and large shift of accelerated deformation stage to short time side was also apparent at comparatively high stresses. Below about 2.2 kg/mm 2 , apparent relief from the degradation was seen. The elongation, however, was found to be due to the formation of numerous intergranular cracks in the premature stage of deformation. Based on the post irradiation tensile properties of several industrial alloys the degree of the ductility loss was found to be nearly dependent on the boron content of the alloys. The post irradiation tensile tests for a special low boron grade heat revealed the means of protecting materials from the effect to be feasible. (author)

  12. Plenary panel 1: The scientific bases of radiation protection. Non-targeted effects of ionising radiation - Implications for radiation protection

    International Nuclear Information System (INIS)

    Salomaa, S.

    2006-01-01

    The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects, genomic instability and adaptive response. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. New aspects include the role of cellular communication and tissue-level responses. A better understanding of non-targeted effects may have important consequences for health risk assessment and, consequently, on radiation protection. Non-targeted effects may contribute to the estimation of cancer risk from occupational, medical and environmental exposures. In particular, they may have implications for the applicability of the Linear-No-Threshold (L.N.T.) model in extrapolating radiation risk data into the low-dose region. This also means that the adequacy of the concept of dose to estimate risk is challenged by these findings. Moreover, these effects may provide new mechanistic explanations for the development of non-cancer diseases. Further research is required to determine if these effects, typically measured in cell cultures, are applicable in tissue level, whole animals, and ultimately in humans. (authors)

  13. Plenary panel 1: The scientific bases of radiation protection. Non-targeted effects of ionising radiation - Implications for radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Salomaa, S. [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2006-07-01

    The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects, genomic instability and adaptive response. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. New aspects include the role of cellular communication and tissue-level responses. A better understanding of non-targeted effects may have important consequences for health risk assessment and, consequently, on radiation protection. Non-targeted effects may contribute to the estimation of cancer risk from occupational, medical and environmental exposures. In particular, they may have implications for the applicability of the Linear-No-Threshold (L.N.T.) model in extrapolating radiation risk data into the low-dose region. This also means that the adequacy of the concept of dose to estimate risk is challenged by these findings. Moreover, these effects may provide new mechanistic explanations for the development of non-cancer diseases. Further research is required to determine if these effects, typically measured in cell cultures, are applicable in tissue level, whole animals, and ultimately in humans. (authors)

  14. Protective effect of urinary trypsin inhibitor on the development of radiation-induced lung fibrosis in mice

    International Nuclear Information System (INIS)

    Katoh, Hiroyuki; Ishikawa, Hitoshi; Suzuki, Yoshiyuki; Ohno, Tatsuya; Takahashi, Takeo; Nakano, Takashi; Hasegawa, Masatoshi; Yoshida, Yukari

    2010-01-01

    This study aimed to analyze whether Ulinastatin, a urinary trypsin inhibitor (UTI), inhibits the transforming growth factor (TGF)-β signaling pathway and lung fibrosis induced by thoracic irradiation in a lung injury mouse model. The thoraces of 9-week-old female fibrosis-sensitive C57BL/6 mice were irradiated with a single X-ray dose of 12 Gy or 24 Gy. UTI was administrated intraperitoneally at a dose of 200,000 units/kg concurrently with radiation (concurrent UTI) or daily during the post-irradiation period for 8-14 days (post-RT UTI). Mice were sacrificed at 16 weeks after irradiation to assess the histological grade of lung fibrosis and immunohistochemical TGF-β expression. Survival rates of mice given 24 Gy to the whole lung ±UTI were also compared. Post-RT UTI reduced the score of lung fibrosis in mice, but concurrent UTI had no beneficial effects in irradiated mice. The fibrosis score in post-RT UTI mice was 3.2±1.0, which was significantly smaller than that of irradiated mice without UTI treatment (RT alone; 6.0±1.3; p 2 =0.26, p<0.01). The survival rate at 30 weeks for post-RT UTI mice was significantly better than that of RT alone mice (33% vs. 10%, p<0.05). The administration of post-RT UTI suppressed TGF-β expression and radiation-induced lung fibrosis, which resulted in significant survival prolongation of the irradiated mice. (author)

  15. DNA protective effect of ginseng and the antagonistic effect of Chinese turnip: A supplementation study.

    Science.gov (United States)

    Szeto, Yim Tong; Wong, Kam Shing; Han, Andrea; Pak, Sok Cheon; Kalle, Wouter

    2016-01-01

    The aim of this clinical study is to provide scientific evidence for supporting traditional Chinese application and usage to the patients. For this purpose, we tested the ability if Panax ginseng extract to lower oxidative damage to nuclear DNA in human lymphocytes by comparing the effect of cooked Chinese turnip on this effect. Seven healthy subjects (4 males and 3 females from 37 to 60 years) participated two occasions which were at least 2 weeks apart. About 2 mL of fasting blood sample for baseline measurement was taken on arrival. They were requested to ingest the content of 5 ginseng capsules in 200 mL water. The subject remained fasting for 2 h until the second blood sample taken. In the other occasion, the experiment was repeated except a piece of cooked turnip (10 g) was taken with the ginseng extract. The two occasions could be interchanged. Comet assay was performed on two specimens on the same day for the evaluation of lymphocytic DNA damage with or without oxidative stress. For the group with ginseng supplementation, there was a significant decrease in comet score for hydrogen peroxide (H 2 O 2 ) treatment over the 2-h period while no change in DNA damage for unstressed sample. For the group with ginseng together with turnip supplementation, there was no significant difference in comet score for both H 2 O 2 treatment and phosphate-buffered saline treatment. Ginseng extract could reduce DNA damage mediated by H 2 O 2 effectively, but this protection effect was antagonized by the ingestion of cooked turnip at the same time. In the current study, commercial ginseng extract was used for supplementing volunteers. Ginseng extract could protect DNA from oxidative stress in vivo while turnip diminished the protection.

  16. Older Adults' Perceptions of Nutrition as Protective against Detrimental Effects of Environmental Pollution

    Science.gov (United States)

    Dunn, Kristina; Gaetke, Lisa; Stephenson, Tammy; Brewer, Dawn

    2017-01-01

    The aging process makes older adults vulnerable to the detrimental health effects of environmental contaminants. Our study assessed older adults' perceptions regarding diet as protective against environmental contaminants, levels of concern about exposure to environmental contaminants, and interest in learning about protective food-related…

  17. The Court of Justice and Effective Judicial Protection: What Has the Charter Changed?

    NARCIS (Netherlands)

    Prechal, A.

    2015-01-01

    Since the coming into force of the Charter as primary law of the EU, Article 47 CFR is ‘the reference standard’ when the Court deals with issues of ffective judicial protection. However, the general principle of effective judicial protection existed already for some 25 years, developed in the case

  18. Labour Market Effects of Employment Protection. IAB Labour Market Research Topics.

    Science.gov (United States)

    Walwei, Ulrich

    The labor market effects of employment protection were examined in a study of Germany's employment protection regulations and their impact on employment practices and patterns. The following topics were considered: (1) the question of whether Germany's labor market problems are a result of regulations; (2) employment security as a subject of labor…

  19. Proposals for software analysis of cost effectiveness and cost-benefit for optimisation of radiation protection

    International Nuclear Information System (INIS)

    Schieber, C.; Lombard, J.; Lefaure, C.

    1990-06-01

    The objective of this report is to present the principles of decision making software for radiation protection option, applying ALARA principle. The choice of optimum options is performed by applying the models of cost effectiveness and cost-benefit. Options of radiation protection are described by two indicators: a simple economic indicator: cost of radiation protection; and dosimetry indicator: collective dose related to protection. For both analyses the software enables sensitivity analysis. It would be possible to complete the software by integrating a module which would take into account combinations of two options since they are not independent

  20. Protecting power equipment against magnetohydrodynamic effects (MHD of electromagnetic pulses (EMP

    Directory of Open Access Journals (Sweden)

    Gurevich Vladimir

    2015-01-01

    Full Text Available The article is devoted to the effects of geomagnetic-induced currents (GIC on electrical equipment of power systems and analyzes technical measures for protection against such effects. It is noted that the difference between highaltitude nuclear detonation and solar storm GICs forces applying different methods of electrical equipment protection. It also illustrates that enhancement of transformer immunity to GICs without saturation prevention is not an effective measure to protect the power system. The article offers a special relay designed for fast disconnection of the transformer under GICs.