Ionic conductivity in irradiated KCL

International Nuclear Information System (INIS)

Vignolo Rubio, J.

1979-01-01

The ionic conductivity of X and gamma irradiated KCl single crystals has been studied between room temperature and 600 deg C. The radiation induced damage resulting in a decrease of the conductivity heals by thermal annealing in two steps which are at about 350 and 550 deg C respectively. It has been found that the radiation induced colour centres are not involved in the observed decrease of the ionic conductivity. Howewer, it has been observed that the effects of quenching and plastic deformation on the conductivity of the samples are very similar to the effect induced by irradiation. It is suggested that small radiation induced dislocation loops might cause the ionic conductivity decrease observed in irradiated samples. (auth)

Effect of irradiation of lipid peroxidation in serum, 2

International Nuclear Information System (INIS)

Haisa, Yoshio

1976-01-01

With blood obtained from patients irradiated for cervical uterine cancer (consisting of 4 cases of Stage I, 5 cases of Stage II and 4 cases of Stage III), changes of blood picture, serum lipid weight and serum lipid peroxide accompanying irradiation were studied on 3 occasions, before, during and after the irradiation. The following results were obtained. Serum lipid and serum lipid peroxide were found to increase along with the advance of uterine cancer from Stage I to II and III. At the termination of irradiation the serum lipid and serum lipid peroxide in the cases of cervical uterine cancer at Stage III were found to have recovered to close to the levels before irradiation, but in the other cases these values tended to increase with irradiation. Except the termination of irradiation treatment of cervical uterine cancer of Stage III, the decrease of leucocyte count has a mutual relationship with the increase of serum thiobarbituric acid (TBA), so that change in the serum TBA level can be assumed to be a criterion for irradiation injury. (auth.)

The feasibility of a study of the late effects of head and neck irradiation

International Nuclear Information System (INIS)

Daal, W.A.J. van; Goslings, B.M.; Hermans, J.; Ruiter, D.J.; Sepmeijer, C.F.; Vink, M.; Vloten, W.A. van

1981-01-01

With the ultimate goal of examining high-risk patients for radiation-induced tumours, and in order to gain more insight into the dose-effect correlations and the latency periods of induced tumours in various organs, a random sample of 2.5% (98 patients) was studied to determine the feasibility of examining all patients irradiated on the cervico-cephalic region for a benign lesion between 1932 and 1963. Thirty of the 98 patients were examined in the out-patient department. Nodular lesions in the thyroid were found in 7 cases. This prevalence is 6 times that to be expected in a non-irradiated population. Useful information was obtained in 82 of the 98 patients (84%). Further examination of the group that had been irradiated for cervical arthrosis was not considered indicated. (Auth.)

Anti-aggregation action of ultraviolet irradiation on platelet-rich plasma in the presence of antioxidants

International Nuclear Information System (INIS)

Roshchupkin, D.I.; Anosov, A.K.; Potapenko, A.Ya.

1983-01-01

UV irradiation of platelet-rich plasma (PRP) results in the inhibition of ADP-induced platelet aggregation. This is accounted for by the long-living photoproducts formed in plasma. Platelets destruct these photoproducts in the dark after irradiation. Lipid antioxidants α-tocopherol and BHT administered in PRP before irradiation reduce the anti-aggregation effect of UV light. Lipid photo-peroxidation is supposed to be responsible for the anti-aggregation effect of UV irradiation on platelet-rich plasma. (Auth.)

Anti-aggregation action of ultraviolet irradiation on platelet-rich plasma in the presence of antioxidants

International Nuclear Information System (INIS)

Roshchupkin, D.I.; Anosov, A.K.; Potapenko, A.Ya.

1983-01-01

UV irradiation of platelet-rich plasma (PRP) results in the inhibition of ADP-induced platelets aggregation. This is accounted for by the long-living photoproducts formed in plasma. Platelets destruct these photoproducts in the dark after irradiation. Lipid antioxidants α-tocopherol and BHT administered in PRP before irradiation reduce the anti-aggregation effect of UV light. Lipid photo-peroxidation is supposed to be responsible for the anti-aggregation effect of UV irradiation on platelet-rich plasma. (Auth.)

Annealing of dislocation loops in neutron-irradiated copper investigated by positron annihilation

International Nuclear Information System (INIS)

Gauster, W.B.; Mantl, S.; Schober, T.; Triftshauser, W.

1975-01-01

Positron annihilation angular correlation measurements were carried out on neutron-irradiated copper as a function of annealing temperature. Two types of specimens were used: single crystals irradiated with fast neutrons, and 10 B-doped polycrystalline samples irradiated with thermal neutrons. All irradiations were at approximately 320 0 K. A structure in the annealing curve, not previously observed by other techniques, indicates that between 460 and 600 0 K the dislocation loops present after irradiation dissociate and more effective positron trapping sites are formed. (auth)

The effect of low-temperature neutron irradiation on the critical current of some superconducting materials

International Nuclear Information System (INIS)

Takamura, S.; Okuda, S.

1978-01-01

The critical current densities of pure V and Nb single crystals, single core Nb-50 wt% Ti coated with Cu and Nb 3 Sn were measured after fast neutron irradiation at about 5 K and during subsequent annealings. The peak effect was observed in V and Nb single cyrstals immediately after irradiation. In V, the peak effect disappeared after subsequent annealing above 200 K (in the so-called stage III recovery where vacancies are considered to anneal out in V). In contrast, in Nb the peak effect did not disappear even after annealing at 300 K (above the stage III recovery of Nb). Furthermore, in V the peak effect showed a remarkable recovery at 120 K where about 50% of the resistivity increase recovered. The elementary force of the fluxoid-defect interaction was estimated in V single crystals. (Auth.)

Comparative study on the effect of RES-stimulating and blockading agents on the immunological response after irradiation

International Nuclear Information System (INIS)

Mori, Kazuhiro; Seto, Akira; Ito, Yohei

1975-01-01

The effects of carbon particles and bacterial endotoxins on immunological recovery after irradiation were compared in relation to the radioprotective effects of the agents. When mice were injected with 10 mg of carbon particles (sufficient to protect the animals from radiation-induced death) 24 hrs prior to the administration of sheep red blood cells, the recovery of their immune response to the antigen was not significantly affected. Administration of 1 mg of carbon particles caused a slight enhancement of immune response. Previous treatment of animals with endotoxin resulted in a significant suppression of the immune response regardless of irradiation, the degree of suppression depending on the dose given. These results strongly suggest that the radioprotective effect of carbon- or endotoxin-treatment is attributable to the apparent RES-blockade and to the enhancement of hemopoietic recovery rather than to the enhancement of immunological recovery after irradiation. (auth.)

Effects of X-irradiation on membranes of tumor cells

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Fonck, K.

1982-01-01

The aim of the investigation was to gain more insight into the effect of ionizing radiation on biomembranes, especially the membrane phospholipids. A general outline of the experimental approach is given in the first chapter. The influence of membrane-active agents and hyperthermia on cell survival after irradiation was studied. Phospholipid turnover was followed by measuring the incorporation of radioactive precursors. The second chapter is an introduction to general radiobiology and to phospholipid metabolism. After the presentation of some physico-chemical properties of ionizing radiation, the effects on cells and cellular components are described. In chapters 3 to 6 the experimental part is described. Chapter 3 starts with the determination of the cellular survival of L5178Y lymphoma cells after X-irradiation. In chapter 4 the lipid composition of lymphosarcoma cell nuclei is presented and in chapter 5 studies on the effect of X-irradiation on the incorporation of palmitate and arachidonate into the phospholipids of lymphosarcoma cells are described. Chapter 6 describes experiments in which lymphosarcoma cells isolated from the spleens of tumor-bearing mice were used to study the effect of a low dose of X-rays (5 Gy) on the incorporation of [ 3 H]palmitate and [ 14 C]arachidonate into the lipids of the tumor cells. These fatty acids were rapidly incorporated especially into the phospholipids of the cells. Chapter 7 contains a general discussion on the experimental results. (Auth.)

Effects of prior stress history on the irradiation creep of 20% cold-worked AISI 316 stainless steel

International Nuclear Information System (INIS)

Chin, B.A.; Straalsund, J.L.; Wire, G.L.

1979-01-01

The following conclusions resulted from this study: An in-reactor transient component of creep is found to occur whenever the stress level is increased. The transient is principally a thermal process, short in duration, and only weakly dependent on flux. The observed irradiation component of in-reactor creep is independent of prior stress history. Microstructural development during irradiation is influenced predominantly by the irradiation flux and temperature variables, and only to a minor extent by the irradiation stress history. (Auth.)

Response of growing bones to irradiation

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Gonzalez Gonzalez, D.

1980-01-01

This thesis describes the effects of ionizing radiations on growing bones. The epiphyseal disc of growing mouse tibia was selected as a model for the experiments. An attempt has been made to obtain clinical data from irradiated bones during the childhood and to quantitate this information. Within the range of possibilities correlations have been established between the experimental and clinical data. (Auth.)

Irradiation of 'carabao' (Manila 'super') mangoes II. Comparison of the effects of gamma radiation and the vapor heat treatment on fruit quality

International Nuclear Information System (INIS)

Lizada, M.C.C.; Esguerra, E.B.; Brena, S.R.; Fuentes, R.A.

1990-01-01

'Carabao' mango fruits subjected to gamma radiation at 100, 150 or 250 Gy resulted in fruits of an acceptable quality. In contrast to the vapor heat treatment, no internal breakdown was observed even in fruits irradiated at 350 Gy. At this dose a low but significant incidence of pulp discoloration was found, albeit in only one trial. Both the vapor heat treatment and gamma radiation need to be supplemented with hot water treatment for effective and more consistent disease control. Although irradiation appears to delay ripening, its effect seems to be largely on peel color development. The results of this study indicate that irradiation might be an appropriate quarantine treatment for the 'Carabao' mango. (Auth.). 7 tabs., 3 figs

Tocopherol in irradiation of temporary hypoxic tumours

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Kaagerud, A.; Lund, N.; Peterson, H.I.

1981-01-01

The influence of tocopherol on the effect of local irradiation under induced ischaemia by temporary tourniquet of two rat tumours transplanted intramuscularly into one hindleg was evaluated. An impaired retardation of growth rate occurred in tumours irradiated under ischaemia. This effect was eliminated by pretreatment of animals with tocopherol. In separate experiments the method of inducing ischaemia was investigated by MDO-electrode measurements of tumour tissue oxygen pressure. A significant tumour hypoxia was found under tourniquet of the tumour-bearing leg of the animals. Pretreatment with tocopherol did not influence the tumour pO 2 . (Auth.)

Spermatogenesis in adult rhesus monkeys following irradiation with X-rays or fission neutrons

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Rooij, D.G. de; Sonneveld, P.; Bekkum, D.W. van

A group of male rhesus monkeys was exposed to total body irradiation followed by autologous bone marrow transplantation. The animals were irradiated in the period between 1965 and 1976 and received a dose of 8.5 Gy of X-rays (300 KVP) or 3.6 Gy of 1 MeV fission neutrons. Of this group, a total of 11 male monkeys proved to be evaluable for studying the effects of irradiation on spermatogenesis. (Auth.)

Late effects of total body irradiation

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Barrett, A.; Gibson, B.

1987-01-01

Late effects of chemo-radiotherapy conditioning before bone marrow transplantation (BMT) are being increasingly recognised in long-term survivors, particularly children. They can be divided into two categories: those affecting hormonal status and those affecting specific organ function. All women treated develop ovarian failure with low levels of β-oestradiol and raised values of follicle-stimulating hormone (FSH) and leutinizing hormone (LH). In males, raised FSH and LH values are found with normal testosterone levels but most patients have azoospermia. In children, puberty is usually but not invariably delayed by treatment but can be induced by appropriate hormone replacement. Compensated hypothyroidism was found in 6/30 children. Growth hormone secretion may be impaired especially if previous cranial irradiation has been given. In children, a reduction in sitting height has been observed. Cataract has occurred in 20% of children between 3 and 6 years after treatment. Two second tumours have been observed. No other major organ toxicities have been encountered. (Auth.)

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

International Nuclear Information System (INIS)

Tomoda, Goro; Matsuyama, Jun; Hiramoto, Keiko; Izu, Kumie

1977-01-01

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

Acute effect of gamma-irradiation on blood vessels of the eye

International Nuclear Information System (INIS)

Matsushima, Hideno

1977-01-01

Radiation injuries to the eye were studied by examining the alteration of fine vasculature of irradiated rabbit eyes, by referring to the usual clinical findings, fundus photography, microangiography, and histological sections. These experiments were performed by using white rabbits whose eyes were locally irradiated with a single dose of 500, 1000, 2000, 3000, and 5000 R of 60 Co-γ-ray. The eyes were observed periodically for a period up to 10 weeks after irradiation, and the following results were obtained: 1) Radiation damage to the blood vessels was maximum around 6 weeks after irradiation for doses less than 2000 R, and the damage appeared to be reversible. 2) When given more than 3000 R irradiation, alteration of the blood vessels continued increasing for 10 weeks with no evidence of recovery. Experimental evidence from these studies supports the hypothesis that the degree of radiation injury of the eye depends highly on the damage to blood vessels serving each structure of the eye. (auth.)

Long-term effect of postoperative irradiation on the immune functions in patients with mammary carcinoma

International Nuclear Information System (INIS)

Toivanen, A.; Nordman, E.

1981-01-01

The effect of postoperative irradiation on the immune functions of 13 patients with breast carcinoma is reported, using as parameters the peipheral blood lymphocyte count, percentages of E and EAC rosette forming cells, and lymphocyte proliferative responses to PHA, Con A and PPD. After irradiation the number of peripheral blood lymphocytes was reduced during 8 months. The percentages of E and EAC rosette forming cells were not altered during the observation time of 7 to 36 months. In the proliferative responses of lymphocytes to PHA, Con A and PPD, the postoperative irradiation caused a decrease which, regarding PHA and Con A, lasted up to 8 months and then recovered. The decrease in the proliferative responses to PPD was stronger and lasted during the whole observation time. In the mitogenic responses of patients with recurrent or disseminating disease no difference could be demonstrated as compared with the patients living recurrence-free. (Auth.)

The effect of deformation twinning on irradiation embrittlement in iron single crystals

International Nuclear Information System (INIS)

Kayano, Hideo; Tokutomi, Shoichiro; Yajima, Seishi; Takaku, Hiroshi.

1978-01-01

Single crystals of iron with the [100] crystal orientation were irradiated in JMTR with fast neutrons to a fluence of 8 x 10 18 n/cm 2 (E > 1 MeV). All samples were deformed in tension at temperatures from liquid nitrogen temperature to 200 0 C at different strain rates using an Instron-type tensile testing machine. Scanning electron microscopy of the fractured surfaces revealed that deformation twinning is difficult to occur in irradiated samples, and also that twins formed in both irradiated and unirradiated samples inhibit fracture nucleation and growth. From the results of tensile deformation of the irradiated samples deformed in tension a different strain rates at 159 0 K, it is conceived that twinning suppression is greater in the irradiated than in the unirradiated samples, and that the nucleation and growth of twins are not necessarily related to those of cracks. It is suggested that the irradiation-induced defects impede plastic deformation of the crystals and deformation twinning is suppressed by irradiation, thus causing the irradiation embrittlement. (auth.)

Neutron irradiation effects on magnetic properties of some Heusler alloys

International Nuclear Information System (INIS)

Onodera, Hideya; Shinohara, Takeshi; Yamamoto, Hisao; Watanabe, Hiroshi

1975-01-01

The neutron irradiation effects were studied with measurements of temperature dependence of magnetization in ordered and disordered Heusler alloys. The irradiation was carried out in JMTR with a total flux of fast neutrons of 10 20 nvt. Fully ordered Cu 2 MnIn, partially ordered Cu 2 MnAl and completely disordered Cu 2 MnSn were prepared with various temperature treatments. The magnetization-temperature curves of each specimen were measured before and after irradiation. In the irradiated Cu 2 MnIn, the disordering by the irradiation gave rise to a decrease of magnetization, and the temperature dependence of magnetization showed that the disordered region contained various regions with different degrees of disorder. For the distribution of the disordered region, the calculation based on the theory of temperature spike by Seitz and Koekler gave a feasible result that a disordered region comprised a central core with a radius of 5.4 A which was completely disordered and a periphery of 3.3 A thickness which was partially disordered. From the magnetization-temperature curves of Cu 2 MnAl, it was considered that the disordered regions induced by the irradiation had different properties from those induced by the heat treatment. The former were the localized and comprised regions corresponding to various degrees of disorder, while the latter spread spatially in a wide range with a certain degree of disorder. The ordering by enhanced diffusion occurred simultaneously to an extent comparable to the disordering, and so it played an important role in the magnetization in the partially disordered Cu 2 MnAl. In the disordered Cu 2 MnSn, however, the ordering effect was very small. It is supposed to be difficult for the A2 structure to transform into the L2 1 structure by the enhanced diffusion. (auth.)

Effect of single and fractionated x-irradiation on maze learning ability of mice

International Nuclear Information System (INIS)

Aoyama, Takashi; Norimura, Toshiyuki; Nakamura, Takeshi; Yoshikawa, Isao

1976-01-01

Fifty-six-day-old male ddk mice at the starting of the investigation were used as subjects through the experiment for 64 weeks. After 15 days' preliminary training, and 16 times of weekly trial training using complete maze, 15 mice received a single 224 rads of x-rays (S group), another 15 mice received two 112 rads spaced two weeks apart (F group) and another 15 mice were sham-irradiated (Control group). Then those mice were tested on the multiple T-maze with nine-choice points and change of performance was observed in terms of errorchoices by giving one test trial a week. We introduced the concept of ''confusional trials'' as an index for surmising to what extent mice failed to exhibit good maze learning habits. In the results, the F group showed significantly worse performance than the two other groups at early stages, opposite to it the S group exhibited the same, but at late stages after irradiation. The worse performance of F group should be considered to be due to the psychological after-effect to fractionated irradiation and that for S group could be assumed to be due to the acceleration of aging by the irradiation. (auth.)

Effect of X-ray irradiation on germination of rice and wheat at different temperatures and pH levels of water

International Nuclear Information System (INIS)

Rajput, T.B.S.; Singh, Jaswant

1981-01-01

An experiment was conducted on the germination of ''Jaya'' rice (Oryza sativa Linn.) and ''Sonalika'' wheat (Triticum aestivum Linn. emend. Thell.) to study the effects of low doses of X-ray irradiation at different temperatures and pH levels of water. The percentage of germination was more at pH 7, and decreased with an increase or decrease in pH level. In most of the cases irradiation delayed the germination and proved to be harmful. But at 20deg C, 4 KR X-ray irradiation promoted the germination of rice by more than 15% at pH levels of 5.5-8.5. But in wheat no significant increase in germination percentage was noted at any combination of the parameters. (auth.)

Review of irradiation experiments for water reactor safety research

International Nuclear Information System (INIS)

Tobioka, Toshiaki

1977-02-01

A review is made of irradiation experiments for water reactor safety research under way in both commercial power plants and test reactors. Such experiments are grouped in two; first, LWR fuel performance under normal and abnormal operating conditions, and second, irradiation effects on fracture toughness in LWR vessels. In the former are fuel densification, swelling, and the influence of power ramp and cycling on fuel rod, and also fuel rod behavior under accident conditions in in-reactor experiment. In the latter are the effects of neutron exposure level on the ferritic steel of pressure vessels, etc.. (auth.)

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

International Nuclear Information System (INIS)

Sawai, Teruko; Shimokawa, Toshinari; Miki, Yasushi; Oseko, Koichi; Sawai, Takeshi

1978-01-01

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

Effects of X-irradiation on some aspects of protein metabolism in the frog, Rana hexadactyla

International Nuclear Information System (INIS)

Rajarami Reddy, G.; Sasira Babu, K.

1980-01-01

Changes in the level of total proteins and protease in brain, muscle and liver tissues of normal and X-irradiated frogs were determined. Low doses of radiation produced an increment in protein level while high doses produced decrement. However, protease activity at all doses exhibited an elevatory trend. Exposure of frogs to lethal doses resulted in increased protease activity and decreased protein content during post-irradiation periods. The results are discussed on the basis of protein destruction and lysosomal damage. (auth.)

Gamma ray irradiation to semi-purified diet

International Nuclear Information System (INIS)

Takigawa, Akihiro; Danbara, Hiroshi; Ohyama, Yoshinobu

1976-01-01

Semi-purified diet containing 10% soybean oil was irradiated with gamma rays at levels of 0.6, 3 and 6 Mrad and was fed to chicks. Crude fat contents of the diets decreased and a considerable amount of peroxide was formed with high doses of irradiation. Feed consumption and feed efficiency of the highly irradiated diets were less than those of control. Metabolizable energy and digestibility of the diets, especially of fat, were decreased with the irradiation. The chicks fed with irradiated diets showed marked dilatation of the small intestine and the liver, and their erythrocytes were more fragile than those of control. The same phenomena were found with the chicks fed the diet containing the oil highly oxidized by autoxidation. Irradiation of the diet excluding oil showed little effect on the growth of chicks. It was considered that these phenomena were caused by the peroxide or other oxidation products of fat which were formed with gamma ray irradiation. (auth.)

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.)

VHTR-fuel irradiation capsules for VT-1 hole of JRR-2

International Nuclear Information System (INIS)

Kikuchi, Teruo; Kikuchi, Akira; Tobita, Tsutomu; Kashimura, Satoru; Miyasaka, Yasuhiko

1977-02-01

Irradiations of VHTR fuels were made in the VT-1 irradiation hole of JRR-2. Three capsules, VP-1, VP-2 and VP-4, which contained fuel compacts, were irradiated for 300 hr at temperatures of 950 0 , 1370 0 and 1500 0 C up to the estimated burn-ups of 0.74, 0.87 and 0.80%FIMA, respectively. And, to study the amoeba effect of fuel particles, two capsules, VP-3 and VP-5, were irradiated for 300 hr at temperatures of 1650 0 and 1670 0 C up to the estimated burn-ups of 0.38 and 0.33%FIMA, respectively. (auth.)

Irradiation combined with Bleomycin treatment of synchronized cells in culture under oxic and hypoxic conditions

International Nuclear Information System (INIS)

Midander, J.; Littbrand, B.; Edsmyr, F.

1980-01-01

Bleomycin-treated cells are sensitized to radiation delivered under oxic conditions both in the early S and G 2 phases of the cycle, irradiated under hypoxic conditions, sensitization occurs only in the early S phase. This difference in the sensitizing effect of the drug is discussed in regard to the possible clinical advantages of a combined treatment of tumours with irradiation and Bleomycin. (Auth.)

Effects of gamma-ray irradiation on tensile properties of ultradrawn polyethylene

International Nuclear Information System (INIS)

Iida, Shozo; Sakami, Hiroshi

1977-01-01

The deformation of ultradrawn polyethylene was previously shown that crystalline chains were pulled out by the tension applied to tie chains which connected crystal blocks. This paper deals with the effects of γ-ray irradiation on crosslinking which prevent crystalline chains being pulled out and to improve the tensile properties. The tensile strength of high density polyethylene, drawn by a factor of 40, increased from 73 to 113 kg/mm 2 at 20 0 C and from 13 to 42 kg/mm 2 at 80 0 C with increasing irradiation dose from zero to 100 Mrad. The tensile elongation, the residual strain measured by cyclic strain test, and the rate of stress decrease by the stress relaxation measurement diminished with increasing irradiation dose. These facts showed the existence of preventive effects by crosslinks on pulling. The stress-strain relation of crosslinked polymer was calculated thermodynamically from the melting of crystalline chains accompanied by the sliding of chains, assuming that the sliding of crystalline chains was brought about by an unbalance of the tension applied to tie chains with which both sides of crystalline chains were connected. The equation of stress was derived; stress increased with increasing strain and was proportional to the Gibbs' free energy of fusion. The observed stress-strain relations obeyed the above mentioned equation. (auth.)

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.)

Studies on a possible using of penicillin and specific globulin for treatment of Siberia ulcer infection in irradiated animals

International Nuclear Information System (INIS)

Strel'nikov, V.A.; Mal'tsev, V.N.

1975-01-01

The efficiency of anti-anthracic globulin and penicillin for treating infectious anthrax was compared in experiments on 160 guinea pigs and 400 white mice irradiated with sub-lethal doses of cobalt-60 gamma rays. It was found that penicillin retained its effectiveness in the irradiated animals whereas anti-anthracic globulin lost much of its therapeutic efficiency. (auth.)

Late effects of x-irradiation in rats, 1

International Nuclear Information System (INIS)

Jankovic-Stejin, V.D.; Kanazir, D.T.

1978-01-01

The present cytogenetic study was made on the bone marrow cells of 48 male rats killed after 9 to 17 months following acute whole-body x-irradiation. We found that exposure to a dose of 700 rads of x-rays, delivered to animals at a high dose-rate (100 rads/min) resulted in a widespread karyotype variability. The number of cell types were existing independently in the haemopoietic tissue within the first week after irradiation, decreased with time. The selection process of persisting abnormalities as well a further evolution of the cells with new karyotypes to clones, were evident after a month following irradiation. Consequently, the analysis of haemopoietic tissue revealed, in 92% of the late survivors, a genetically heterogeneous cell population in which the number of normal diploid cells decreased to a considerable extent. Clones increased in size with elapsing time from exposure to radiation. Thus, the mean clone cell frequency for animals killed after 9 to 17 months following irradiation ranged from 20.6 +- 3.42% to 61.6 +- 4.26%. Analysis of the data showed a significant positive correlation between development of clones in vivo and the survival time after irradiation (r = 0.820; P<0.01). For such a finding, the occurrence of large clones especially in the bone marrow of rats with growing tumors was of the great influence. Relationship between the degree of mutagenesis on the chromosome level and the process of tumor advancement is discussed. (auth.)

Functional recovery in the irradiated kidney following removal of the contralateral unirradiated kidney

International Nuclear Information System (INIS)

Robbins, M.E.C.; Hopewell, J.W.; Golding, S.J.

1986-01-01

Radiation-induced damage to one kidney in the pig causes a fall in total renal function; this would be recognised and lead to a compensatory response in the unirradiated kidney. The presence of the unirradiated contralateral kidney may effectively prevent the irradiated kidney from expressing any potential for repair and/or recovery of function. If this were true then the question would obviously arise, does the irradiated kidney retain some capacity for recovery? In order to answer this question, the contralateral unirradiated kidney was removed from pigs 26 weeks after the irradiation of the other kidney. The subsequent response of the irradiated kidney to nephrectomy was assessed in terms of the changes in renal size and haemodynamics, i.e. GFR and effective renal plasma flow (ERPF). (Auth.)

After irradiation of the throat or nose area: pay attention to the eye

International Nuclear Information System (INIS)

Balen, A.Th.M. van

1984-01-01

Radiotherapy of carcinomas in the nose can give delayed side effects on the visual system. In this article four cases are described, in which a neuropathy of the optical nerve, caused by vascular damaging, developed one to three years after radiotherapy of nose-neoplasms, with total irradiation doses of 7000 rad. (Auth.)

Effects of gamma irradiation on rapeseed meal with special reference to the quantitative changes in oxazolidinethione and other constituents

International Nuclear Information System (INIS)

Nakaya, Tetsuro

1978-01-01

Experiments were carried out to confirm whether the irradiation treatment of rapeseed meal with gamma rays was effective in reducing the goitrogenic effect of meal, and to obtain the information on the reasonable dose level to reduce the above effect. The rapeseed meals from two ordinary and one non-commercial low glucosinolate (Brassica napus L. cv. Bronowski) seeds were exposed to gamma rays of 5, 10, 50 and 100 Mrad respectively. And the changes in oxazolidinethone (OZT) content of these meals by the irradiation were investigated compared with those by the autoclaving treatment under the reasonable condition. The influences of irradiation treatment on the content of the several constituents of meal were also examined. Furthermore, with chicks, the influences of irradiation treatment on the palatability of meal and on the apparent digestibility of its crude protein or crude fiber were investigated. When two ordinary meals were irradiated at the level of 50 Mrad or above, their OZT content reduced to the level of that in a low glucosinolate meal (Bronowski meal) and such irradiation dosages also resulted in a loss of the available lysine (AL) of meals. The extent of the above changes in the contents of OZT and AL was similar to that in rapeseed meal which was autoclaved under the reasonable condition. Treatment at irradiation dosage of either 50 or 100 Mrad resulted in lower crude fiber and higher reducing sugar content than those of non-irradiated meal respectively. Tests with chicks revealed that an irradiation treatment tended to improve the palatability and the crude fiber digestibility of meal but had no appreciable effect on the digestibility of its crude protein. In summary, these findings indicate that the gamma irradiation at dosage of 50 Mrad or above as well as the autoclaving treatment under the reasonable condition is effective in reducing the goitrogenic effect of rapeseed meal. (auth.)

Fractionated total body irradiation; the gastrointestinal toxicity versus the conditioning effect for bone marrow transplantation with different fractionation schedules

International Nuclear Information System (INIS)

Walma, E.P.; Klapwijk, W.M.; Miller, A.M.

1982-01-01

In most cases, bone marrow transplantation is preceded by a conditioning regimen employing irradiation and/or cytotoxic drugs. The authors are searching for better fractionation schedules in order to optimize the conditioning regimen prior to transplantation of stem-cell-enriched bone marrow. They have determined damage to the gastrointestinal tract in dogs and mice after total body irradiation in mice and dogs following a number of fractionation schedules, and these results are presented. The schedules were chosen such as to minimize the interval between irradiation and the bone marrow transplantation and to maximize clinical feasibility. (Auth./C.F.)

Repopulation in irradiated pig skin: late versus early effects

International Nuclear Information System (INIS)

Redpath, J.L.; Peel, D.M.; Dodd, P.; Simmonds, R.H.; Hopewell, J.W.

1985-01-01

In the first 16 weeks after irradiation, two distinct waves of reaction can be observed in pig skin, the first wave (3-9 weeks) represents the expression of damage to the epithelium while the second is indicative of primary damage to the dermis, mediated through vascular injury. Comparison of single doses with two equal doses separated by 28 days produced a D 2 -D 1 value of 14.0 Gy at the doses which produced moist desquamation in 50% of fields (ED 50 ) after strontium-90 irradiation. After X-irradiation, comparison of ED 50 doses for the later dermal reaction suggested a D 2 -D 1 value of 4.2 Gy. These values of D 2 -D 1 for epithelial and dermal reactions in pig skin were compared with earlier data from this laboratory for similar split-dose experiments with a one-day interval. Such a comparison allowed for the estimation of the component of recovery in the present 28-day interval experiments due to repopulation. This component was found to be 6.5 Gy for the early epithelial damage, but was zero for the later dermal damage. (Auth.)

Alloys of nickel-iron and nickel-silicon do not swell under fast neutron irradiation

International Nuclear Information System (INIS)

Silvestre, G.; Silvent, A.; Regnard, C.; Sainfort, G.

1975-01-01

This research is concerned with the effect of fast-neutron irradiation on the swelling of nickel and nickel alloys. Ni-Fe (0-60at%Fe) and Ni-Si (0-8at%Si) were studied, and the fluences were in the range 10 20 -4.3x10 22 n/cm 2 . In dilute alloys, the added elements are dissolved and reduce swelling, silicon being particularly effective. In more concentrated alloys, irradiation of Ni-Fe and Ni-Si alloys brings about the formation of plate-shaped precipitates of Ni 3 X and these alloys do not swell. (Auth.)

Long-term feeding studies in mice fed a diet containing irradiated fish. I

International Nuclear Information System (INIS)

Petten, L.E. van; Calkins, J.E.; McConnell, R.F.; Gottschalk, H.M.; Elias, P.S.

1980-01-01

A wholesomeness feeding study was carried out in mice fed equal amounts of cod or redfish, comprising 45% of the diet. Three groups of animals received either irradiated [1.75 kGy (175 krad)] fish, non-irradiated fish or stock ration. A 90-day subchronic study, a multigeneration reproduction, a dominant lethality and a teratology study were carried out together with an 80-week oncogenic study on the F 1 generation. No adverse effects were noted on growth, reproduction and litter behaviour, in relation to dominant lethality, teratogenicity or oncogenicity. (Auth.)

Effects of acute gamma-irradiation on spermatogenesis as revealed by flow cytometry

International Nuclear Information System (INIS)

Hacker, U.; Schumann, J.; Goehde, W.

1980-01-01

Mice irradiated with doses ranging from 0.1 to 15 Gy using a 60 Co-source and controls were killed at intervals varying from 2 to 35 days after irradiation. The DNA content of the testicular cells in single cell suspensions was measured with the pulse cytophotometer to determine the frequencies of the different stages in the spermatogenesis. The relative amount of S-phase and 4c-cells was reduced initially but increased subsequently to hypernormal values. A decrease of 2c-cells indicated a higher cell-kill of diploid spermatogonia. Gamma ray-induced spermatids with abnormal DNA-values (diploid sperm) were identified. The results suggest that the spermatogenesis can be analysed with flow cytometry and used as a biologic dosimeter even for small doses of ionizing radiation. (Auth.)

Polymerization of vinyl stearate multilayers by electron beam irradiation

International Nuclear Information System (INIS)

Nishii, Masanobu; Hatada, Motoyoshi

1975-01-01

Studies on the radiation-induced polymerization of vinyl stearate (VST) multilayers were carried out. The VST multilayers built-up on an aluminum plated glass plate by Langmuir-Blodgett technique were irradiated with electron beams from a Van de Graaff electron accelerator in nitrogen atmosphere. The structure of the multilayers and the effects of irradiation were investigated by X-ray diffractometry, contact angle measurement, multireflection infrared spectroscopy, and scanning electron microscopy. The VST multilayers became insoluble to methanol by the irradiation, and the multi-reflection infrared spectrum of the VST multilayers turned into that of poly (VST) with increasing dosage. The polymerization proceeded during the irradiation at the temperature range between -10 0 and 10 0 C, and the conversion attained to 90% within 2.5 minutes (total dose, 5.6 Mrads). The multilayers irradiated above 13 Mrads turned into the polymer film insoluble to benzene, indicating that the polymer chains were cross-linked by the irradiation. Stearic acid which was formed by the irradiation of VST at nitrogen-water interface as a hydrolysis product was not detected in this system. (auth.)

Spin trapping of radicals formed in gamma-irradiated methanol: effect of the irradiation temperature from 77K to 300K

International Nuclear Information System (INIS)

Schlick, S.; Kevan, L.

1976-01-01

The neutral radicals formed in gamma-irradiated methanol were studied by spin trapping with phenyl-t-butylnitrone (PBN) in an attempt to probe the primary neutral radicals formed. In the temperature range from approximately 157 K to 300 K both CH 2 OH and CH 3 O spin adducts are observed and their limiting ratio at high PBN concentrations is CH 2 OH/CH 3 O=1.5 over this temperature range. Below approximately 157 K this ratio increases exponentially with decreasing temperature with an apparent activation energy of 5.8 kJ/mole (1.4 kcal/mole); this is consistent with the finding that only CH 2 OH radicals are formed by gamma radiolysis at 77 K. Several possible models for the primary neutral radicals formed in gamma-irradiated methanol and their subsequent reactions as a function of irradiation temperature are discussed. It is suggested that the primary radical formation mechanisms are similar in the gas and liquid phases and become temperature dependent when molecular motion is arrested in the solid. (Auth.)

The enhancing effect of fractionated whole-body x-irradiation on replication of endogenous leukemia viruses in BALB/c mice

International Nuclear Information System (INIS)

Takamori, Yasuhiko; Okumoto, Masaaki; Iwai, Mineko; Iwai, Yoshiaki

1976-01-01

The incidence of leukemia, changes in the tissue weight of spleen and thymus, and the expression of endogenous viruses were examined with BALB/c mice following 4 weekly fractionated whole-body x-irradiation of 170 R each, starting at 4 weeks of age. The leukemia incidence was quite low for the unirradiated controls, while 60% of the irradiated male mice developed thymic lymphoma. The virus-positive cells appeared earlier in the spleen than in the thymus and bone marrow, and increased with aging. The time of appearance of virus-positive cells in these tissues was remarkably promoted by the fractionated x-irradiation, and its frequency was also enhanced. (auth.)

(100) faceted anion voids in electron irradiated fluorite

International Nuclear Information System (INIS)

Johnson, E.

1979-01-01

High fluence electron irradiation of fluorite crystals in the temperature range 150 to 320 K results in formation of a simple cubic anion void superlattice. Above 320 K the damage structure changes to a random distribution of large [001] faceted anion voids. This voidage behaviour, similar to that observed in a range of irradiated metals, is discussed in terms points defect rather than conventional colour centre terminology. (Auth.)

Studies on the supposition of liquid source for irradiation and its dose distribution, (1)

International Nuclear Information System (INIS)

Yoshimura, Seiji; Nishida, Tsuneo

1977-01-01

Recently radio isotope has been used and applied in the respective spheres. The application of the effects by irradiation will be specially paid attention to in the future. Today the source for irradiation has been considered to be the thing sealed in the solid state into various capsules. So we suppose that we use liquid radio isotope as the source for irradiation. This is because there are some advantages compared with the solid source in its freedom of the shape or additional easiness at attenuation. In these experiments we measured the dose distribution by the columnar liquid source. We expect that these will be put to practical use. (auth.)

The proposed cold neutron irradiation facility at the Breazeale reactor

International Nuclear Information System (INIS)

Dimeo, R. M.; Sokol, P. E.; Carpenter, J. M.

1997-01-01

We discuss the design considerations of a Cold Neutron Irradiation Facility (CNIF) originally to have been installed at the Penn State Breazeale Reactor (PSBR). The goal of this project was to study the effects of radiation-induced damage to cryogenic moderators and, in particular, solid methane. This work evolved through the design stage undergoing a full safety analysis and received tentative approval from the PSBR Safeguards Committee but was discontinued due to budgetary constraints. (auth)

Effects of fast neutron irradiation on the development of the mouse brain

International Nuclear Information System (INIS)

Deguchi, Hisao

1977-01-01

Mice on the 4th to 11th day of pregnancy were irradiated with 14.1 MeV fast neutron at a dose of 100 rad and their fetuses were examined macroscopically and histologically on the 9th to the 19th day of gestation. Sixty-one cases out of 73 malformed fetuses (20.3%) were arbitrarily chosen and examined. Two cases of exencephaly were observed by irradiation on the 7th day of pregnancy, 2 cases of microcephaly by irradiation on the 9th day, 2 cases of hydrocephaly by irradiation on the 6th day and 3 cases of hydrocephaly by irradiation on the 11th day. Three cases of tumor were observed by irradiation on the 7th day of pregnancy and one case of tumor by irradiation on the 10th day. One case each of abnormal folding of the pallium was detected by irradiation on the 7th day and 10th day of pregnancy. After irradiation, penetration of blood vessels into the developing brain resembles to that of the control group. In some cases, invasion of fibroblast-like cells was observed. In cases with tumor formation, the tumors consisted of homogeneous ventricular cells without any sign of malignancy. Three to four days after irradiation on the 10th or 11th day of pregnancy, rosette formation was observed in the pallium which later disappeared. It appears that slight damages of brain tissue could be repaired without resulting in any external morphological abnormalities. (auth.)

Inverse gamma ray dose rate effect in californium-252 RBE experiment with human T-1 cells irradiated in vitro

International Nuclear Information System (INIS)

Todd, P.; Feola, J.M.

1986-01-01

Metabolically deoxygenated suspensions of human T-1 cells were used to determine the RBE in hypoxia of low dose rate (LDR) Cf-252 radiation compared to LDR gamma radiation. Based upon the initial portion of the survival curves the RBE was 5.0 ± 1.0 for all components of the Cf-252 radiation and 7.1 ± 1.7 for the neutrons alone. An inverse dose rate effect was observed for LDR gamma radiation in which greater cell sensitivity was observed at lower dose rates and longer irradiation periods. It was demonstrated that there was little or no sublethal damage repair or cell progression during LDR at 21 deg C, and the observed decrease in cell survival probability with increasing irradiation time at a given dose was attributable to reoxygenation of the cell suspensions during the course of LDR exposures. (Auth.)

Structural changes of ultraviolet-irradiated DNA derived from hydrodynamic measurements

International Nuclear Information System (INIS)

Triebel, H.; Reinert, K.E.; Baeer, H.; Lang, H.

1979-01-01

The paper reports on sedimentation and viscosity measurements performed on ultraviolet-irradiated DNA from T7 phage and calf thymus. From the hydrodynamic data the relative changes in the mean molecular weight, radius of gyration, and effective Kuhn statistical segment length were calculated. The results show that ultraviolet irradiation (254 nm) leads to a significant decrease of the effective statistical segment length of DNA which may be due to small local helix kinks (produced by the generation of photodimers) and a local increase of chain flexibility. Alterations in the overall DNA conformation may be observed even at low fluence where the mean molecular weight almost stays constant. The locally distorted helix regions possibly may serve as recognition sites in the first step of excision repair. (Auth.)

Shallow irradiation of Citrus Unshiu by cathod ray, 2

International Nuclear Information System (INIS)

Takano, Hiroyuki; Kawashima, Koji; Umeda, Keiji

1978-01-01

The effect of 150 Krad cathode ray irradiation on the shelf life and quality of ''Citrus Unshiu'' was investigated. Citrus Unshiu (Japanese mandarin orange ''Satsuma'') were kept at 5 0 C for 2 months without pretreatment and irradiated. Both irradiated and non-irradiated samples were stored in the special storage boxes in which temperature, humidity and sterile air circulation were controlled. After 44 days, the percentage of spoiled oranges in irradiated and non-irradiated samples stored at 8 0 C were 57.5% and 64% respectively, on the other hand when stored at 3 0 C the percentage were 26% and 51% respectively. Rate of spoilage was significantly lower in the irradiated samples than non-irradiated ones. Irradiated effect on the shelf life extension was more conspicuous when the storage temperature was kept at 3 0 C. By the sensory examination, any difference for taste and flavor between irradiated and non-irradiated samples was not detected. The taste and flavor of the oranges stored at 8 0 C changed worse after long time storage but when stored at 3 0 C, such tendency was not observed. Undesirable odor and flavor were not detected by the panel with the irradiated samples in this experiment. The results showed that shelf life of the ''Citrus Unshiu'' could be extended by the combination of irradiation with 150 Krad cathode ray and storage at 3 0 C. (auth.)

The development of the cholinergic system in rat hippocampus following postnatal X-irradiation

International Nuclear Information System (INIS)

Ben-Barak, J.

1981-01-01

Postnatal X-irradiation of the rat hippocampus results in a marked reduction in the number of the postnatally developing granular neurons in the dentate gyrus and also caused a marked increase in the specific activity of acetylcholinesterase (AChE) and choline acetyltransferase (CAT) and a slight but consistent increase in the activity per whole hippocampus of AChE. The effect of irradiation on the granular neurons and on the cholinergic enzymes was found to be dose and age dependent. Drastic increase in specific enzymatic activities is also observed in the irradiated cerebellum whose granular neurons differentiate postnatally and to a lesser extent in the cerebral cortex in which cell formation is accomplished prior to birth. (Auth.)

Irradiation techniques for the release of bound heavy metals in natural waters and blood

International Nuclear Information System (INIS)

Batley, G.E.; Farrar, Y.J.

1978-01-01

Irradiation techniques are compared with conventional acid digestion procedures for the release of bound heavy metals in natural waters and in blood, before their determination by anodic stripping voltammetry. Ultra-violet irradiation of acidified water with a 550-W mercury vapour lamp releases bound zinc, cadmium, lead and copper after 4 h. The same results can be achieved with a 30 Mrad dose of high-energy γ-irradiation. These techniques are also effective for the release of metals in whole blood and blood plasma, where sample volumes as small as 200 μl are adequate in analyses for zinc, copper and lead. By comparison with acid digestion and solvent extraction methods, irradiation treatments offer the advantages of minimum sample manipulation and negligible reagent blanks. (Auth.)

Hormonal protection of spermatogenic stem cells during irradiation

International Nuclear Information System (INIS)

Kroonenburgh, M.J.P.G. van.

1986-01-01

In this thesis it is examined if by hormonal suppression of spermatogenesis the disadvantageous side-effects of radiation therapy on the gonads can be reduced. Therefore a rat model was investigated, where hormonal suppression of spermatogenesis during irradiation was achieved and stem cell survival was measured. Attention was focussed on the stem cell, because this cell is primarily responsible for the late effects of radiation on fertility. Flow cytometrical and histological techniques were used as parameters for measuring stem cell survival. Serum concentrations of FSH, LH and testosterone were measured to evaluate the hormonal suppression. (Auth.)

Tolerance of the central nervous system to photon irradiation

International Nuclear Information System (INIS)

Wigg, D.R.; Murray, R.M.L.; Koschel, K.

1982-01-01

Dose-response isoeffect equations have been determined for hypothalamic pituitary insufficiency following cranial irradiation. Of particular importance is the occurrence of complications at doses substantially less than those commonly used for the treatment of central nervous system tumors. Such complications may be severe and potentially life threatening. These complications occur when a small midline 'target' volume containing the pituitary gland, infundibulum and adjacent inferior hypothalamic structures is irradiated. Direct pituitary irradiation is unlikely to be a factor, at least in some cases. The possible role of incidental hypothalamic irradiation in the control of acromegaly and pituitary dependent Cushing's syndrome is discussed. (Auth.)

Effect of gamma-irradiation to prevent the spoilage of 'retainer type Kamaboko'

International Nuclear Information System (INIS)

Ito, Hitoshi; Iizuka, Hiroshi.

1978-01-01

The species of main microorganisms which can grow in retainer-Kamaboko a kind of fish meat jelly products were Bacillus subtilis and B. pumilus at 20 0 C, and B. pumilus, B. megaterium, b. cereus, Pseudomonas and yeasts at 10 0 C. When Kamaboko was stored at 5 0 C, microorganisms capable to grow were the species of Pseudomonas, Brevibacterium, Aeromonas and yeasts. Irradiation of Kamaboko at 300 krad and 450 krad reduced the aforementioned flora to the Bacillus and yeasts, and the storage life of Kamaboko was extended about 2 times at 10 0 C. The growth of Bacillus strains at 10 0 C was suppressed for 3 days or more after destruction to about 95% of the total viable cells by irradiation at 300 krad. The putrefaction in retainer-Kamaboko was brought mainly by Bacillus, which seemed to be originated mainly from starch at a manufacturing process. The number of microorganisms in Potato starch was 200 per gram, and they were consisted mainly of Bacillus. These bacteria in starch could be almost eliminated by means of 500 krad irradiation. (auth.)

Long-term feeding studies in mice fed a diet containing irradiated fish. II

International Nuclear Information System (INIS)

Benson, H.G.; Miller, T.J.; Gottschalk, H.M.; Elias, P.S.

1980-01-01

Three groups of mice (Fsub(2b) generation of Part I study) were fed for 90 days, either stock ration or diets containing 45% fish, either non-irradiated or irradiated with 1.75 kGy. Equal amounts of cod and redfish (ocean perch) constituted the fish portion of the diet. Haematological and clinical chemical examinations revealed no treatment-related effects. There were no untoward terminal gross or histopathological changes. An initial lag in weight gain of males fed fish diets was attibuted to reduced food consumption, due to the difference in texture of the fish diets compared with the stock ration. (Auth.)

Radiation effects on lifespan of the fish Oryzias latipes

International Nuclear Information System (INIS)

Egami, N.

1979-01-01

The mortality rate of adult fish exposed to continuous γ-ray irradiation was examined and the results summarized. Initial results into the effects of low-dose γ-irradiation during early developmental stages (one day embryo - 3 month old young) on lifespan, indicate that in this fish the life-shortening effects of radiation are marked at high doses but not at low doses. Age-related histological changes in various tissues have been observed in both irradiated and non-irradiated fish. (Auth.)

X-ray and fast neutron-induced mutations in Arabidopsis thaliana, and the effect of dithiothreitol upon the mutant spectrum

International Nuclear Information System (INIS)

Dellaert, L.M.W.

1980-01-01

The author discusses the genetic effects of X-ray and fast neutron seed-irradiation of Arabidopsis thaliana (L.) Heynh., and the influence of a pre-irradiation treatment with the radio-protector dithiothreitol (DTT). (Auth.)

Effect of experimental immune atrophic gastritis on the induction of gastric carcinoma by x-irradiation in ICR mice

International Nuclear Information System (INIS)

Hirose, Fumio; Watanabe, Hiromitsu; Takeichi, Nobuo; Naito, Yukiko; Inoue, Shozo

1976-01-01

Divided doses of 6,000 or 8,000 rad of x-ray were given to the gastric region of ICR/JCL female mice with immune atrophic gastritis produced by the injection with allogenic stomach antigen. The carcinogenic effect of x-rays for inducing gastric carcinoma was significantly increased by this method. Two points can be presented as its reason. First, the pyloric gland mucosa regenerating from injuries by immunization was exposed to the divided doses of x-rays. Second, the marked requirement of gastrin secretion attributable to severe injuries of parietal cell mass by immunization and local x-irradiation acted as a promoting factor on the induction of gastric carcinoma by x-ray for a long time through the trophic effects on the pyloric gland. (auth.)

Ectopic intestinal glands after segmental small bowel irradiation in the cat

International Nuclear Information System (INIS)

Rubio, C.A.; Eriksson, B.; Johnsson, L.

1983-01-01

Following segmental irradiation of the small bowel, 5 of 64 cats demonstrated ectopic intestinal glands in the submucosal tissue. In addition, one of these 5 cats had foci of abnormal glands in the muscularis mucosae. In 2 of the 5 animals, cellular polymorphism, nucleolar irregularity and loss of cellular polarity were present in irradiation-induced ectopic intestinal glands. The review of the literature indicates that intestinal irradiation may induce intestinal adenocarcinomas with metastatic growth. The possibility that ectopic intestinal glands are precancerous lesions in the irradiated cat is discussed. (Auth.)

Irradiation deformation due to SIPA induced dislocation anisotropy

International Nuclear Information System (INIS)

Woo, CH.

1980-02-01

A contribution to irradiation deformation resulting from the stress-induced preferred adsorption (SIPA) effect is considered. SIPA causes a variation of the growth rates of irradiation-generated dislocation loops, according to the alignment of their Burgers vectors with respect to the applied stress. A prolinged period under an applied stress then creates an anisotropic dislocation structure in which the majority of dislocations have their Burgers vectors in alignment with the stress. In the presence of 'neutral' sinks, the resulting anisotropic dislocation structure causes plastic deformation similar to the way in which irradiation growth occurs in zirconium. This mechanism is called SIPA-induced growth (SIG). We have shown that SIG is very significant in comparison to SIPA, except when little or no loop growth has occurred during the period the stress is applied. This report contains the detailed formulation and derivation of the formulae for the evaluation of the contribution due to SIG. (auth)

Effect of temperature during UV and gamma irradiations of TL phosphor CaSO4:Dy

International Nuclear Information System (INIS)

Nagpal, J.S.; Pendurkar, H.K.

1979-01-01

Temperature is an important parameter in thermoluminescence studies. Irradiation at enhanced temperatures reduces the γ response of TL phosphor CaSO 4 :Dy. However, in the presence of fluorescent lights, the γ response of the phosphor is enhanced by approximately 20% for temperatures around 60-100 0 C. If the phosphor temperature during UV exposure is kept high, the integrated TL output continues to increase until it reaches 18 times at 160 0 C as compared to that produced by UV exposure at room temperature. (Auth.)

Recovery from inhibition of transcription in γ-irradiated Euglena cells

International Nuclear Information System (INIS)

Tsushimoto, G.; Kikuchi, T.; Ishida, M.R.

1982-01-01

Transcriptional activity was inhibited with low doses of γ-irradiation which did not cause the death of cells, but induced the delay of cell division in the unicellular alga Euglena. The incorporation of [ 14 C]uracil into cells was inhibited to about 50% of non-irradiated cells immediately after 3 krad irradiation. The suppressed transcriptional activity was gradually recovered after irradiation. At about 12 h post-irradiation, the rate of incorporation of [ 14 C]uracil recovered to that of non-irradiated cells. The synthesis of ribosomal RNA was inhibited immediately after 3 krad irradiation, but it recovered within 12 h after irradiation. The synthesis of cytosol ribosomal RNA precursor was more strongly inhibited than that of other cytosol ribosomal RNAs. The synthesis of cytoplasmic organelle ribosomal RNA was also inhibited and recovered after 3 krad irradiation. (Auth.)

Inhibition of DNA repair in ultraviolet-irradiated human cells by hydroxyurea

International Nuclear Information System (INIS)

Francis, A.A.; Carrier, W.L.; Smith, D.P.; Regan, J.D.; Blevins, R.D.

1979-01-01

The effect on DNA repair in ultraviolet-irradiated human skin fibroblasts by hydroxyurea has been examined in this study using three independent methods for measuring DNA repair: the 5-bromodeoxyuridine photolysis assay which measures DNA repair replication, chromatographic measurement of thymine-containing dimers, and measurement of specific ultraviolet-endonuclease-sensitive sites in irradiated DNA. Little effect on hydroxyurea was observed at the concentration of 2mM, which is often used to inhibit semiconservative DNA synthesis; however, 10 mM hydroxyurea resulted in marked inhibition (65-70%) of excision repair. This inhibition was accompanied by a possible doubling in the size of the repaired region. The accumulation of large numbers of single-strand breaks following ultraviolet irradiation and hydroxyurea incubation seen by other investigators was not observed with the normal skin fibroblasts used in this study. A comparison of hydroxyurea effects on the different DNA repair assays indicates inhibition of one step in DNA repair also results in varying degrees of inhibition of other steps as well. (Auth.)

Low-temperature deuteron irradiation of differently reacted Nb3Sn superconductors

International Nuclear Information System (INIS)

Maier, P.; Seibt, E.

1978-01-01

Irradiation measurements with 50 MeV deuterons at 18 K and subsequent annealing measurements were performed on Nb 3 Sn single and multifilamentary superconductors at the Helium-Bath Irradiation Facility of the Karlsruhe Cyclotron. The critical current densities jsub(c) of Nb 3 Sn bronze-reacted wire samples at various reaction temperatures (Tsub(R)=650,700,750,800 and 850 0 C) with equal layer thickness were measured for integral deuteron fluxes up to PHIsub(t)=0.7x10 18 cm -2 . After a decrease in jsub(c) of 85% at maximum dose a relatively small annealing effect (4 to 10%) was observed at ambient temperatures. The maximum value of the normalized critical current density, jsub(c)/jsub(c0), at PHIsub(t)approximately=10 17 cm -2 increases with increasing reaction temperature. The difference in volume pinning forces before and after irradiation increases less than linear (approximately√PHIsub(t)) with the irradiation dose. An almost linear dependence between the inverse grain diameter (dsub(K) -1 )) and volume pinning force is obtained both before and after irradiation. (Auth.)

Experimental study associated to irradiation of FBR structural material, (4)

International Nuclear Information System (INIS)

1976-01-01

The study presents one of the bases to evaluate the results of the post-irradiation tests to conduct the thermal control tests related to the second JMTR irradiation (70M-61P) of the demestic austenitic stainless steels for the structural material of the FBR performed by Power Reactor and Nuclear Fuel Development Corporation. The thermal control specimens were given the temperature history which simulated that of the irradiation temperature in vacuum by the electrical furnance, and then the tensile, fatigue and Charpy impact tests were performed. The changes of the material properties caused by the thermal history were investigated. (auth.)

A disposal centre for irradiated nuclear fuel: conceptual design study

International Nuclear Information System (INIS)

1980-09-01

This report describes a conceptual design of a disposal centre for irradiated nuclear fuel. The surface facilities consist of plants for the preparation of steel cylinders containing irradiated nuclear fuel immobilized in lead, shaft headframe buildings, and all necessary support facilities. The undergound disposal vault is located on one level at a depth of 1000 metres. The cylinders containing the irradiated fuel are emplaced on a one-metre thick layer of backfill material and then completely covered with backfill. All surface and subsurface facilities are described, operations and schedules are summarized, and cost estimates and manpower requirements are given. (auth)

Biliary and pancreatic secretions in abdominal irradiation

International Nuclear Information System (INIS)

Becciolini, A.; Cionini, L.; Cappellini, M.; Atzeni, G.

1979-01-01

The biliary and pancreatic secretions have been determined in patients given pelvic or para-aortic irradiation, with a dose of 50 Gy in the former group and between 36 and 40 Gy in the latter. A test meal containing polyethylene glycol (PEG) as reference substance was used. Each sample of the duodenal content was assayed for volume, PEG content, amylase and trypsin activity, pH and biliary secretion. No significant modifications of biliary and pancreatic secretions were demonstrated after irradiation, suggesting that these functions are not involved in the pathogenesis of the malabsorption radiation syndrome. (Auth.)

Potential for irradiation of marine foods in New Zealand

International Nuclear Information System (INIS)

Burns, D.J.W.

1984-01-01

The potential for treatment of fish with ionising radiation to extend the useful shelf life lies with low dose pasteurization methods. A practical extension of 1 week or more under optimal refrigeration conditions can be achieved although a background loss of quality due to autolysis continues throughout storage. Of New Zealands markets for fish products only Australia could be serviced by sea freight with irradiated fresh fish. Two difficulties are forseen: firstly a market advantage for fresh over frozen fish is unproven; secondly the industry is dispersed and does not lend itself to a central irradiation facility. Some possibilities for irradiation may arise in future. (auth.)

Irradiation enhanced diffusion and irradiation creep tests in stainless steel alloys

International Nuclear Information System (INIS)

Loelgen, R.H.; Cundy, M.R.; Schuele, W.

1977-01-01

A review is given of investigations on the rate of phase changes during neutron and electron irradiation in many different fcc alloys showing either precipitation or ordering. The diffusion rate was determined as a function of the irradiation flux, the irradiation temperature and the irradiation dose. It was found that the radiation enhanced diffusion in all the investigated alloys is nearly temperature independent and linearly dependent on the flux. From these results conclusions were drawn concerning the properties of point defects and diffusion mechanisms rate determining during irradiation, which appears to be of a common nature for fcc alloys having a similar structure to those investigated. It has been recognized that the same dependencies which are found for the diffusion rate were also observed for the irradiation creep rate in stainless steels, as reported in literature. On the basis of this obervation a combination of measurements is suggested, of radiation enhanced diffusion and radiation enhanced creep in stainless steel alloys. Measurements of radiation enhanced diffusion are less time consuming and expensive than irradiation creep tests and information on this property can be obtained rather quickly, prior to the selection of stainless steel alloys for creep tests. In order to investigate irradiation creep on many samples at a time two special rigs were developed which are distinguished only by the mode of stress applied to the steel specimens. Finally, a few uniaxial tensile creep tests will be performed in fully instrumented rigs. (Auth.)

Selective survival of β1-adenergic receptors in rat cerebellum following neonatal X-irradiation

International Nuclear Information System (INIS)

Minneman, K.P.; Pittman, R.N.; Wolfe, B.B.; Molinoff, P.B.

1981-01-01

To investigate the cellular localization of β 1 - and β 2 -adrenergic receptors, the effects of intermittent neonatal X-irradiation focused on the cerebellum were determined on the densities of the two subtypes of β-adrenergic receptor. This treatment destroys the late-maturing cerebellar interneurons including the granule, basket and stellate cells. The total number of β 2 -adrenergic receptors per cerebellum was reduced by 81-83% in 6- and 12-week-old X-irradiated rats. However, the number of β 1 -adrenergic receptors per cerebellum in 6- and 12-week-old X-irradiated rats was not significantly different from that in control animals. The results suggest that β 2 receptors in the rat cerebellum are primarily associated with the small interneurons destroyed by neonatal X-irradiation. The β 1 receptors may be located on a cell population which is unaffected by this treatment, possibly on cerebellar Purkinje cells. (Auth.)

Storage and irradiation of Cucumis pollen and their influence on pollen vitality

International Nuclear Information System (INIS)

Oost, E.H.; Nijs, A.P.M. den

1979-01-01

In connection with an interspecific hybridization programme and a mentor pollen experiment in Cucumis, the optimal storage conditions and in vitro germination medium for both fresh and irradiated pollen of the cultivated cucumber and two wild African Cucumis species have been searched for. (Auth.)

The paradoxes in patterns and mechanism of bone marrow regeneration after irradiation. 1

International Nuclear Information System (INIS)

Scarantino, C.W.; Rubin, P.; Constine, L.S. III

1984-01-01

Bone marrow regeneration following irradiation has been largely studied as a dose-effect phenomenon, however, a large literature has simultaneously developed utilizing a wide variety of volumes, both in clinical studies and in experimental studies. Volume factors, more than dose, determine patterns of suppression and regeneration which have been documented by a variety of assay systems. Experimental evidence is presented which indicates that high dose irradiation to large volumes of bone marrow does not completely suppress bone marrow regeneration but results in a rapid compensatory response. Comparisons are made between the small and larger volumes at similar doses and indicate a greater overall compensatory response after the larger field irradiation, being more rapid in onset particularly after the 1000 rad dose. Although in-field regeneration of bone marrow occurs after single dose radiation to different volumes of bone marrow, experimental and clinical evidence from protracted conventional doses of irradiation to different volumes of bone marrow indicate significantly different response mechanisms. (Auth.)

Heat-shock-induced enhanced reactivation of UV-irradiated Herpesvirus

Energy Technology Data Exchange (ETDEWEB)

Yager, J.D.; Zurlo, J.; Penn, A.L.

1985-09-01

The objective of this study was to compare the ability of heat shock (HS) with that of another type of cellular stress, UV irradiation, to cause the induction of enhanced viral reactivation, a process that may represent an SOS-type repair process in mammalian cells. These results indicate that, like UV irradiation, HS at levels inhibitory to cell growth induced enhanced viral reactivation in Vero cells. The results also suggest that at least two proteins in the HS protein family are not necessary for this response to occur. (Auth.). 27 refs.; 5 figs.

Status of IVO-FR2-Vg7 experiment for irradiation of fast reactor fuel rods

International Nuclear Information System (INIS)

Elbel, H.; Kummerer, K.; Bojarsky, K.; Lopez Jimenez, J.; Otero de la Gandara, J.L.

1979-01-01

Report on the Seminar celebrated in Madrid between KfK (Karlsruhe) and JEN (Madrid) concerning a Joint Irradiation Program of Fast Reactor Fuel Rods. The design of fuel rods in general is defined, and, in particular of those with a density 94% DT and diameter 7.6 mm up to a burn-up of 7% FIMA, to be irradiated in the FR2 Reactor (Karlsruhe). Together with the design of NaK and single-wall capsules used in this irradiation, other possibilities of irradiation in the reactor will also be described. (auth.)

The effects of radiation on the diseases of aging in experimental animals: gerontological significance

International Nuclear Information System (INIS)

Hollander, C.F.; Zwieten, M.J. van; Broerse, J.J.

1979-01-01

A study of the effect of different types and doses of ionizing radiation on the induction of mammary tumours in rats and the role of ovarian hormones in tumour indication is reported. The occurrence of other diseases in the irradiated animals is also studied and compared to those occurring in non-irradiated controls. (Auth.)

'In situ' straining in the HVEM of neutron irradiated copper crystals

International Nuclear Information System (INIS)

Johnson, E.; Hirsch, P.B.

1976-01-01

High energy neutron irradiated copper single crystals strained 'in situ' in the high voltage electron microscope are observed to yield in relatively few strongly developed slip bands. The deformation in the slip bands is caused by glide of inclined dislocations close to screw orientation belonging to the primary slip system. Radiation induced point defect clusters are swept up by the dislocations whereby superjogs are formed. Some of the jogs will be sessile and act as pinning points for the gliding dislocations, which bow out under the applied stress to form perfect dipoles mainly of edge nature, as well as faulted dipoles, which are finally pinched off. The effective stress measured from the radius of curvature of the bowed-out dislocations is in agreement with resolved flow stress measurements from irradiated bulk crystals. (Auth.)

Sister-chromatid exchange induced by X-ray of human lymphocytes and the effect of L-crysteine

International Nuclear Information System (INIS)

Abramovski, I.; Vorsanger, G.; Hirschhorn, K.

1978-01-01

A staining technique that detects sister-chromatid exchanges (SCEs) has been used to examine the response of human lymphocyte chromosomes to various dosages of X-irradiation. The SCE frequency was markedly increased following irradiation. However, the increase was of a significantly smaller magnitude when irradiation occurred in the presence of an antimutagenic agent. Scoring SCEs may provide a useful technique for assaying the mutagenic effects of environmental carcinogens as well as the protective effects of antimutagenic agents. (Auth.)

A standard fission neutron irradiation facility

International Nuclear Information System (INIS)

Sahasrabudhe, S.G.; Chakraborty, P.P.; Iyer, M.R.; Kirthi, K.N.; Soman, S.D.

1979-01-01

A fission neutron irradiation facility (FISNIF) has been set up at the thermal column of the CIRUS reactor at BARC. The spectrum and the flux have been measured using threshold detectors. The paper describes the setting up of the facility, measurement and application. A concentric cylinder containing UO 2 powder sealed inside surrounds the irradiation point of a pneumatic sample transfer system located in the thermal column of the reactor. Samples are loaded in a standard aluminium capsule with cadmium lining and transported pneumatically. A sample transfer time of 1 s can be achieved in the facility. Typical applications of the facility for studying activation of iron and sodium in fission neutrons are also discussed. (Auth.)

Mechanisms and kinetics of precipitate restructuring during irradiation

International Nuclear Information System (INIS)

Potter, D.I.; Wiedersich, H.

1979-01-01

Irradiations were performed at temperatures from 400 to 700 0 C using 3.0-MeV 58 Ni + ions in order to investigate γ'-precipitate restructuring in two model alloys: Ni-12.8 at% Al and Ni-12.7 at% Si. The precipitates coarsened, with the third power of the average diameter proportional to the damage dose. The temperature dependence of the rate constants for irradiated specimens is described in terms of a modified Lifschitz-Slyozov-Wagner coarsening model that includes radiation-enhanced diffusion. Redistribution of precipitate by enhanced precipitation (Ni-Si) or precipitate dissolution (Ni-Al) at point-defect sinks caused maxima in γ' size with dose. Precipitate redistribution at the free surfaces of irradiated thin foils and at γ/γ' particle interfaces is described. (Auth.)

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)

The relationship between survival and mutagenesis in Escherichia coli after fractionated ultraviolet irradiation

International Nuclear Information System (INIS)

Dzidic, S.; Salaj-Smic, E.; Trgovcevic, Z.

1986-01-01

The relationship between survival and mutagenesis in Escherichia coli after fractionated ultraviolet (UV) irradiation was studied. The cells were incubated either in buffer or nutrient media. Regardless of incubation conditions, greater survival is observed after fractionated irradiation than after acute irradiation. When the cells are incubated in buffer, UV mutagenesis decreases with an increase in the number of dose fractions. However, when the cells are cultivated in nutrient media, the increased survival is coupled with the enhanced capacity for UV mutagenesis. The authors, therefore, assume that during incubation in nutrient media, fractionated irradiation leads to full and prolonged expression of all UV inducible (SOS) genes, including those required for mutagenesis. (Auth.)

The effect of caffeine on post-replication repair and survival in two L5178Y cell lines with different sensitivities to UV irradiation

International Nuclear Information System (INIS)

Walicka, M.; Beer, J.Z.; Koerner, I.; Malz, W.

1978-01-01

2 Strains of murine lymphoma L5178Y cells that varied from the point of view of sensitivity to UV irradiation (mean lethal doses: 3.6 and 8.5 J/m 2 for L5178Y-R and L5178Y-S cells, respectively) also differed with respect to sensitization by caffeine. L5178Y-S cells were sensitized to UV irradiation by 0.75 mM caffeine, whereas in the same conditions L5178Y-R cells were not sensitized. Sedimentation analysis of the newly synthesized DNA indicated UV-induced gap formation in L5178Y-S cells only. The subsequent gap filling was inhibited by caffeine. Exposure to UV irradiation induced no gaps in L5178Y-R cells. However, when caffeine was added immediately after irradiation, DNA with reduced molecular weight was found in irradiated cells of both strains after a 2-h chase. On the other hand, caffeine inhibited elongation of undamaged DNA strands in neither of the 2 cell strains. (Auth.)

Color changes of vienna sausage by gamma irradiation

International Nuclear Information System (INIS)

Kume, Tamikazu; Aoki, Shohei; Sato, Tomotaro

1978-01-01

Color change of vienna sausage induced by gamma irradiation was investigated. Discoloration of irradiated vienna sausage was evaluated by use of the color difference meter and sensory test. The discoloration by irradiation was influenced by oxygen contents in packing pouches. In the case of commercial vienna sausage, significant difference from unirradiated control by 99% of probability was recognized at the doses of 1.0 Mrad in nitrogen, 0.5 Mrad in air and 0.3 Mrad in oxygen, respectively. The color change of the specially prepared vienna sausage (40% pork, 40% mutton, 20% beef, and no additional preservatives) was less than that of the commercial one. The absorbance at 540 nm of extracts from vienna sausages with 80% acetone decreased with increasing irradiation dose and oxygen content. While, change in absorbance at 340 nm was practically unaffected by the oxygen concentration. These results suggest that the degradation of nitroso-heme complex by irradiation causes mainly the discoloration of vienna sausage. (auth.)

The effects of gamma irradiation on the volatile components of desiccated coconut during storage

International Nuclear Information System (INIS)

Acevedo, T.P.; Azanza, M.P.

1989-11-01

Flavor volatiles of desiccated and irradiated desiccated coconut stored for 24 weeks at room temperature were identified and quantified by gas chromatography. Chromatograms of fresh coconut meat revealed sone esters, ketones, aldehydes and alcohols which were responsible for its fruity odor. The oily odor of fresh coconut meat was attributed to minimal amount of delta lactones. Freshly desiccated coconut contained the same volatiles responsible for the fresh fruity odor but the concentration of the delta lactones was considerably higher. The newly irradiated desiccated coconut had the highest concentration of the delta lactones with other volatiles such as ethyl caproate, 1-hexanol, and caprylic aldehyde being also present. With storage, development of oily odor to rancid odor was noted due to increasing amount of delta lactones. Corresponding decrease of volatiles responsible for the fresh fruity odor was noted as shown by the chromatographic profiles of both irradiated and unirradiated samples. Odor deterioration was more pronounced in the irradiated sample. Significant changes in moisture content, peroxide and iodine values, and free acid were observed during storage. No significant changes, however were noted in percent oil, pH and water activity. Significant difference in color, taste and general acceptability were noted at the start of storage with odor changes becoming more evident only after 4 weeks of storage. (Auth.). 69 refs.; 15 figs.; 14 tabs.; Appendix p. 90-205

Lack of radiation protective effect of orgotein in normal and malignant mammalian cells

International Nuclear Information System (INIS)

Overgaard, J.; Nielsen, O.S.; Overgaard, M.; Steenholdt, S.; Jakobsen, A.; Sell, A.

1979-01-01

The potential radiation protective effect of orgotein, a metalloprotein with superoxide dismutase activity, was investigated in L 1 A 2 tumour cells in vitro, jejunal crypt cells and C 3 H mouse mammary carcinoma in vivo. No effect of orgotein, given either 2 hours before irradiation or 30 min after, was observed compared to the effect of irradiation alone. Thus, it was concluded that orgotein did not influence the primary radiation response in air in mammalian cells. (Auth.)

Effect of ionizing radiation on platelet function in vitro

International Nuclear Information System (INIS)

Kalovidouris, A.E.; Papayannis, A.G.

1981-01-01

The effect of ionizing radiation on platelet function was investigated in vitro. Platelet-rich plasma (300x10 9 /l) was irradiated with doses of 1, 4, 10, 20 and 50 Gy. Platelet function tests were performed on both irradiated and control (non-irradiated) platelet samples. The platelet function tests were (1) platelet aggregation by ADP (1, 2, 4 μmol final concentration), adrenaline and collagen, (2) ADP-release from platelets, (3) clot retraction and (4) platelet factor-3 availability. It was found that roentgen irradiation of platelets in vitro did not affect these platelet function tests. (Auth.)

Studies on gamma-irradiation of high amylose corn starch, 1

International Nuclear Information System (INIS)

Watanabe, Yukio; Ayano, Yuko; Obara, Tetsujiro.

1976-01-01

Amylomaize 7, amylomaize 5, normal corn, waxy corn and potato starches were irradiated with 60 Co-gamma rays at the dose levels from 2x10 4 to 100x10 4 rad to determine the changes in physicochemical properties by irradiation. Irradiated starches were characterized by determination of amylography, specific viscosity, blue value, pH, acidity, carbonyl content, reducing value and limit of β-amylolysis. Irradiated starches showed a decrease in viscosity and blue value, and an increase in reducing value with increasing dose levels. These results were seemed to indicate the degradation of starch molecule. A slight oxidation of starch was suggested by a decrease in pH and an increase in acidity and carbonyl content. Amylomaize 7 and amylomaize 5 starches were less sensitive than the other starches in terms of irradiation effects. The rheological properties determined by amylography and Ostwald viscometer changed at the lowest dose (5x10 4 rad) and the other properties changed above 20x10 4 rad. The limits of β-amylase hydrolysis of normal corn, waxy corn and potato starches increased slightly by irradiation (100x10 4 rad). On the other hand, β-amylolysis limits of amylomaize 7 and amylomaize 5 starches were lower about 5.5% and 2.5% respectively than that of nonirradiated samples. The decrease of β-amylolysis limit enlarged with increasing amylose content. (auth.)

Effect of x-irradiation in rats bearing walker-256-carcinosarcoma and normal rats

International Nuclear Information System (INIS)

Ehara, Kazuhiko

1978-01-01

Serum protein fractions and total proteins were studied with bloods obtained from the rats exposed each to the partial-, whole-bodies and the transplanted tumors (Walker-256-carcinosarcoma transplanted in the right hind leg). The electrophoretic variation induced in the sera of tumor-bearing rats (Group II), and the content of total proteins decreased. Early irradiation to the tumor part of rats less induced the variations of the electrophoretic pattern and the decrease of the amount of serum total proteins. When the distant metastasis appeared during irradiation treatment, the electrophoretic patterns and content of total proteins changed proportionally to the variation in sera of Group II. On the other hand, the γ-globulin (G) fraction increased in the long-term survival rat. The separation of the rat serum β-G into two peaks of β 1 - and β 2 -G was shown only in Group IV (late irradiation to the right hind leg). This finding supposed that some factors involve in the sera of rats with transplanted primary tumor grown up to a fixed size and guessed the appearance of the distant metastasis during x-irradiation. The percentages of the albumin and γ-G decreased slightly and those of the α 1 -, α 2 - and β-G increased slightly in the rats with 300 rad partial-body (the right hind leg) x-irradiation daily for 20 days. The remarkable decrease of the albumin and γ-G, the increase of the α 1 - and β-G, the marked increase of the α 2 -G and the decrease of serum total proteins were demonstrated for the sera of rats with 1,000 rad whole-body x-irradiation at a time. These phenomena seem to be related to the destructive and reticuloendothelial injury by the exposure. (auth.)

Effects of neutron irradiation and fatigue on ductility of stainless steel DIN 1.4948

International Nuclear Information System (INIS)

Vries, M.I. de; Schaaf, B. van der; Staal, H.U.; Elen, J.D.

1978-10-01

Test specimens of stainless steel DIN 1.4948, which is similar to AISI type 304, have been irradiated at 723 K and 823 K up to fluences of 1.10 23 neutrons (n).m -2 and 5.10 24 n.m -2 (E > 0.1 MeV). These are representative conditions for the SNR-300 reactor vessel and inner components after 16 years of operation. High temperature (723 K to 1023 K) tensile tests at strain rates (depsilon/dt) from 10 -7 s -1 to 10 s -1 show a considerable decrease of tensile ductility. The extent depends on helium content, test temperature and strain rate. The atomic helium fractions of 3.10 -7 and 7.10 -6 result from the reactions of thermal neutrons with the 14 ppm boron, present in the steel. Helium embrittlement sets in at strain rates below 1 s -1 to 10 s -1 (the range of interest for Bethe-Tait accident analyses). A minimum total elongation value of 6% is shown at 923 K. The post-irradiation fatigue life is reduced by up to about 50% due to intergranular cracking. The combination of irradiation and fatigue causes a decrease of ductility after a smaller number of prior fatigue cycles than in the case of unirradiated material. (Auth.)

Shrubs of the Field Irradiator - Gamma area in eastern Manitoba

International Nuclear Information System (INIS)

Dugle, J.R.; Mayoh, K.R.; Barclay, P.J.

1979-11-01

Detailed descriptions and line drawings are given of over 100 shrub taxa (including semi-woody shrubs and vines) which are common in Manitoba; most of them are found within the Field Irradiator - Gamma (FIG) area or its immediate surroundings. Ecological and morphological notes are included along with a few general remarks on the effects of exposure to long-term gamma radiation. Keys are given for certain genera, small family groups or other critical species groups. This document is intended to facilitate identification of shrubs for experimental purposes in the FIG projects, and it should also be useful to those who are generally interested in the shrubs of Manitoba. (auth)

Radiation effects control: eyes, skin. Final report, 1 October 1969--31 December 1974

International Nuclear Information System (INIS)

Hightower, D.; Smathers, J.B.

1974-12-01

Adverse effects on the lens of the eye and the skin due to exposure to proton radiation during manned space flight were evaluated. Actual proton irradiation which might be encountered in space was simulated. Irradiation regimes included single acute exposures, daily fractionated exposures, and weekly fractionated exposures. Animals were exposed and then maintained and examined periodically until data sufficient to meet the objective were obtained. No significant skin effects were noted and no serious sight impairment was exhibited. (auth)

Effect of irradiation on carbohydrates content

International Nuclear Information System (INIS)

Chantharasakul, S.

1971-01-01

Effect of gamma radiation on vitamin C and total acidity contents of Hom Tong banana was described. There was a slight decrease in vitamin C contents in both irradiated and non-irradiated banana during storage. No difference was detected in term of vitamin C contents between irradiated and non-irradiated banana at any storage time. The total acidity of the banana increased with increasing time of storage owing to the ripening effect of the fruit. Higher total acidity content of non-irradiated banana during storage indicated the faster rate of ripening of the fruit

A computer program (FUGI) for design and operation of a conveyor type irradiator with multi-tier and multi-layer

International Nuclear Information System (INIS)

Hoshi, Tatsuo; Aggarwal, K.S.

1976-10-01

A computer program (FUGI) was established to facilitate the determination of factors related to design and operation of a conveyor type irradiator with multi-tier and multi-layer. The factors determined by this program are as follows: (1) maximum dose, minimum dose and dose uniformity in irradiated material; (2) dose rate distribution on the path of irradiated material; (3) mass flow rate of irradiated material; (4) requisite activity of source; (5) requisite speed of conveyor; (6) utilization efficiency. This program partly uses the program FUDGE 4A for determination of dose rate in irradiated material in static state by Galanter and Krishnamurthy. (auth.)

Total lymphoid irradiation in rhesus monkeys

International Nuclear Information System (INIS)

Vriesendorp, H.M.; Maat, B.; Hogeweg, B.

Total lymphoid irradiation (TLI) consists of three contiguous fields, a mantle, an inverted Y and a spleen field. TLI induces a state of immunosuppression in patients with Hodgkin disease or in small rodents. Infusion of allogeneic bone marrow cells into mice after TLI led to the development split haemopoietic chimerism and indefinite survival of skin grafts from the bone marrow donor. A protocol for TLI was developed for rhesus monkeys to attempt to verify these interesting observations in a pre-clinical animal model. (Auth.)

Fractionated vs acute irradiation: the effects of treating adult boll weevils (Coleoptera: Curculionidae) at different ages

International Nuclear Information System (INIS)

Haynes, J.W.; Wright, J.E.; Mattix, E.

1979-01-01

When 6-7 days old mass-reared ebony boll weevils, Anthonomus grandis Boheman, were given 25 doses of γ-irradiation totaling 6625 rads, mortality was 14%-15% less 1 week later than when young weevils (1-2 day-old) were similarly treated. However, giving older weevils an acute dose of 6625 rads did not reduce mortality. Seven-day-old weevils receiving the acute treatment mated 10% more than weevils that were 3 days old at the time of treatment. Seven-day-old male weevils exposed to the fractionated treatment transferred sperm to 12% more females than 7-day-old males exposed to the acute treatment. (Auth.)

Food irradiation technology and some implications for New Zealand

International Nuclear Information System (INIS)

Roberts, P.B.; Sutton, H.C.

1986-01-01

The use of irradiation in the food industry overseas is growing steadily, but it is likely to be several years before New Zealand industry makes extensive use of the process. The design, operation, and likely costs of facilities to provide controlled doses of radiation to foods are reviewed. Different sources of radiation 60 Co, 137 Cs, accelerators, and mobile units) and a variety of package handling methods are discussed. (auths)

Influence of adjuvant irradiation on shoulder joint function after mastectomy for breast carcinoma

International Nuclear Information System (INIS)

Ryttov, N.; Blichert-Toft, M.; Madsen, E.L.; Weber, J.

1983-01-01

The influence of postoperative radiation therapy on ipsilateral shoulder function following mastectomy was evaluated from a series of 52 women with primarily operable carcinoma of the breast. Mastectomy and partial axillary dissection were carried out in all patients. In addition, 29 of the patients received postoperative irradiation with 36.6 Gy applied mid-axillarily in 12 fractions with irradiation twice a week. A significant impairment of the active shoulder mobility was found in the irradiated group (p<0.01). The passive mobility did not differ significantly between the two groups. The impairment of active shoulder mobility is suggested to be caused by radiation induced subcutaneous fibrosis. (Auth.)

Effect of packaging films on the microflora of gamma irradiated vienna sausages

International Nuclear Information System (INIS)

Ito, Hitoshi; Watanabe, Hiroshi; Aoki, Shohei; Sato, Tomotaro

1977-01-01

Slime production of radurized VS (vienna sausage) was prevented largely in a package of O 2 gas unpermeable films such as K-cellophane and EG-Q more than cellophane-polyethylene film when packed with N 2 gas and stored at 10 0 C, 90% r.h. All of the total microbial count in non-irradiated VS packed in every film reached 1 x 10 6 per gram after 2 to 3 days storage, and slime production was observed at this level. In the case of radurized VS, the total count reached 1 x 10 6 per gram after 4 to 5 days at 300 krad and after 7 to 8 days at 500 krad in cellophane-polyethylene, while it prolonged for 7 to 9 days at 300 krad and for more than 13 or 15 days at 500 krad in K-cellophane or EG-Q. The main microorganisms occurring in non-irradiated VS packed with N 2 or CO 2 gas in K-cellophane or EG-Q were lactic acid bacteria, and the growth of other organisms such as MA (an Intermediate type of Moraxella-Acinetobacter), yeasts and Micrococcus was suppressed under these conditions. The growth of surviving organisms consisting of MA and yeasts in radurized VS was also suppressed. A small amount of off-flavor detected after irradiation at 500 krad disappeared in cellophane-polyethylene after 7 days storage. But it remained in the O 2 gas unpermeable films. (auth.)

Studies on the flavour and aroma of peel oil from citrus unshu irradiated with cathode ray

International Nuclear Information System (INIS)

Nagashima, Toshio; Asari, Takayasu; Obara, Tetsujiro

1975-01-01

The flavor of peel oil from citrus unshu irradiated with 150 krad cathode ray were investigated by gas chromatography. The sample irradiated and stored for 30 days showed browning and unfavorable odor although the degree of the browning was not same as the report of Ojima et al. The yield of essential oil showed only a slight difference in all samples. Some changes were found in the carbohydrate components immediately after irradiation, whereas some changes were detected in hydrocarbon components, especially d-linonen and pinene after storage of irradiated samples. Unfavorable odor might be caused by the changes of quantitative ratio of the components. (auth.)

Pyrolysis of γ-ray irradiated poly(tetrafluorethylene) powder

International Nuclear Information System (INIS)

Kagiya, Tsutomu; Yokoyama, Norio; Ueno, Toru

1974-01-01

Pyrolysis of γ-ray irradiated poly(tetrafluoroethylene) powder (PTFE) has been studied at temperatures from 200 0 C to 390 0 C in the presence of air. By heating, the weight decrease of the powder and the formation of gaseous CO 2 and CO were observed. The weight decrease of the powder increased with total dose of irradiation. γ-ray irradiated PTFE decomposed partly by heating above 250 0 C. By heating at 300 0 C, the degree of weight decrease increased with heating time and reached a constant value. While at 390 0 C, successive decomposition was observed. The melting point of PTFE was depressed by irradiation, while it did not change by heating. No change of IR spectrum of PTFE by irradiation and/or heating was observed. In the irradiated PTFE, stable peroxy radical was observed by ESR measurement at room temperature, but decreased by heating at 150 0 C and disappeared at 250 0 C. Upon pre-heating the irradiated PTFE above 200 0 C, the weight decrease of the powder at 390 0 C decreased remarkably. On the basis of these results, mechanisms of the pyrolysis and thermo-stabilization of the irradiated PTFE were discussed. (auth.)

Performance of a sphere-pac mixed carbide fuel pin irradiated in the Dounreay Fast Reactor (DFR 527/1 experiment)

International Nuclear Information System (INIS)

Bischoff, K.; Smith, L.; Stratton, R.W.

1980-10-01

The DFR 527/1 experiment was the first irradiation of EIR sphere-pac uranium-plutonium mixed carbide fuel in a fast flux. The experiment has been successfully irradiated to a burn-up of 7.3% FIMA at ratings between 45 and 62 kW m - 1 and clad temperatures between 300 and 600 0 C. Restructuring and elemental redistribution has been found to be similar to the pattern established for pellet type fuel and follows effects seen in earlier sphere-pac carbide tests. Gas release of 12-14% has been measured. A preliminary comparison of radial temperature distribution calculations using a first version of the fuel behaviour modelling code SPECKLE with the actual metallography has been attempted. (Auth.)

dLocAuth: a dynamic multifactor authentication scheme for mCommerce applications using independent location-based obfuscation

Science.gov (United States)

Kuseler, Torben; Lami, Ihsan A.

2012-06-01

This paper proposes a new technique to obfuscate an authentication-challenge program (named LocProg) using randomly generated data together with a client's current location in real-time. LocProg can be used to enable any handsetapplication on mobile-devices (e.g. mCommerce on Smartphones) that requires authentication with a remote authenticator (e.g. bank). The motivation of this novel technique is to a) enhance the security against replay attacks, which is currently based on using real-time nonce(s), and b) add a new security factor, which is location verified by two independent sources, to challenge / response methods for authentication. To assure a secure-live transaction, thus reducing the possibility of replay and other remote attacks, the authors have devised a novel technique to obtain the client's location from two independent sources of GPS on the client's side and the cellular network on authenticator's side. The algorithm of LocProg is based on obfuscating "random elements plus a client's data" with a location-based key, generated on the bank side. LocProg is then sent to the client and is designed so it will automatically integrate into the target application on the client's handset. The client can then de-obfuscate LocProg if s/he is within a certain range around the location calculated by the bank and if the correct personal data is supplied. LocProg also has features to protect against trial/error attacks. Analysis of LocAuth's security (trust, threat and system models) and trials based on a prototype implementation (on Android platform) prove the viability and novelty of LocAuth.

Selective irradiation for fast switching thyristor with low forward voltage drop

International Nuclear Information System (INIS)

Brown, J.L.

1975-01-01

The switching speed of a thyristor is increased without correspondingly increasing the forward voltage drop by selectively irradiating at least portions of the PN junction between the conducting and gating portions, and 5 to 30 percent of the adjacent surface area of the conducting portions of the device. 50 to 100 percent of the surface area of the gating portions, and the peripheral portions can also be irradiated at the same time to decrease gate sensitivity and increase blocking voltage of the thyristor, respectively. Preferably, the thyristor is irradiated with electron radiation which preferably is of an intensity greater than 1 MeV and most desirably about 2 MeV. The electron irradiation is preferably to a dosage of between about 1 x 10 13 electrons/cm 2 and 1 x 10 15 electrons/cm 2 . (auth)

A reliable method for reconstituting thymectomized, lethally irradiated guinea pigs with bone marrow cells

International Nuclear Information System (INIS)

Terata, N.; Tanio, Y.; Zbar, B.

1984-01-01

The authors developed a reliable method for reconstituting thymectomized, lethally irradiated guinea pigs. Injection of 2.5-10 x 10 7 syngeneic bone marrow cells into adult thymectomized, lethally irradiated guinea pigs produced survival of 46-100% of treated animals. Gentamycin sulfate (5 mg/kg of body weight) for 10 days was required for optimal results. Acidified drinking water (pH 2.5) appeared to be required for optimal results. Thymectomized, lethally irradiated, bone marrow reconstituted ('B') guinea pigs had impaired ability to develop delayed cutaneous hypersensitivity to mycobacterial antigens and cutaneous basophil hypersensitivity to keyhole limpet hemocyanin; proliferative responses to phytohemagglutinin were impaired. (Auth.)

Studies on c-AMP contents in sea urchin eggs fertilized with normal and x-irradiated sperm

International Nuclear Information System (INIS)

Kimura, Hiroshi

1975-01-01

Intracellular levels of cyclic 3', 5'-adenosine monophosphate (c-AMP) seemed to remain constant through the first cleavage cycle of sea urchin eggs. X-irradiation to the sperm, which induced the first cleavage delay, did not change this level. Although it was shown in the previous paper that X-ray-induced cleavage delay was reduced by caffeine but not by aminophyline, both caffeine and aminophyline caused an increase in c-AMP levels. These results indicated the possibility that c-AMP does not mediate this caffeine effect on cleavage delay. (auth.)

Hypopituitarism as a delayed result of irradiation of the facial skin

International Nuclear Information System (INIS)

Boers, G.H.J.; Jong, M. de

1978-01-01

This paper describes a man aged 63 with complaints and deficiencies caused by hypopituitarism. Examination of the endocrine functions showed that the deficiency was generally of hypothalamic origin. The most plausible cause of this hypothalamic dysfunction proved to be damage due to an overdose of skin irradiation of both cheeks and the nose, in the treatment of a cutaneous form of lupus erythematosus. (Auth.)

Dechanneling measurements of defect depth profiles and effective cross-channel distribution of misaligned atoms in ion-irradiated gold

International Nuclear Information System (INIS)

Pronko, P.P.

1976-01-01

Defect depth profiles for self-ion and He + irradiated gold are obtained from single and multiple scatter dechanneling analysis in single-crystal gold films. Quantitative defect densities are obtained through use of atomic-scattering cross sections. Integral damage profiles are extracted from the dechanneling spectra and subsequently differentiated to yield the volume concentration of defects as a function of depth. Results from the self-ion irradiations suggest that incident ions produce defect distributions across depths much greater than predicted by random stopping theory. This is in agreement with TEM observations of others. Comparison of the experimental profiles is made with theoretical vacancy distributions predicted by defect diffusion in a radiation environment. Similarities are observed for the low-fluence irradiations, suggesting that profile characteristics may be controlled by rapid migration and loss of interstitials to the film surfaces during irradiation. Information on the across-channel distribution of misaligned atoms in the damaged films is obtained with the steady increase of transverse energy model. A predominance of slight misalignment is observed with no contribution to dechanneling coming from atoms displaced significantly close to the center of the channels. This is in keeping with what is expected for crystal distortions caused by the strain fields associated with vacancy cluster defects. (Auth.)

Influence of second phase dispersion on void formation during irradiation

International Nuclear Information System (INIS)

Sundararaman, M.; Banerjee, S.; Krishnan, R.

Irradiation-induced void formation in alloys has been found to be strongly influenced by the microstructure, the important microstructural parameters being the dislocation density and the nature, density and distribution of second-phase precipitates. The effects of various types of precipitates on void swelling have been examined using the generally-accepted model of void formation : void embryos are assumed to grow in a situation where equal numbers of vacancies and interstitials are continuously generated by the incident irradiation, the interstitials being somewhat perferentially absorbed in some sinks present in the material. The mechanism of the trapping of defects by a distribution of precipitates has been discussed and the available experimental results on the suppression of void formation in materials containing coherent precipitates have been reviewed. Experimental results on the microstructure developed in a nickel-base alloys, Inconel-718 (considered to be a candidate material for structural applications in fast reactors), have been presented. The method of determination of the coherency strain associated with the precipitates has been illustrated with the help of certain observations made on this alloy. The major difficulty in using a two-phase alloy in an irradiation environment is associated with the irradiation-induced instability of the precipitates. Several processes such as precipitate dislocation (in which the incident radiation removes the outer layer of precipitates by recoil), enhanced diffusion disordering, fragmentation of precipitates, etc. are responsible for bringinq about a significant change in the structure of a two-phase material during irradiation. The effect of these processes on the continued performance of a two-phase alloy subjected to irradiation at an elevated temperature has been discussed. (auth.)

Kraft cooking of gamma irradiated wood, (1). Effect of alcohol additives on pre-irradiation

Energy Technology Data Exchange (ETDEWEB)

Inaba, M; Meshitsuka, G; Nakano, J [Tokyo Univ. (Japan). Faculty of Agriculture

1979-12-01

Studies have been made of kraft cooking of gamma irradiated wood. Beech (Fagus crenata Blume) wood meal suspended in aqueous alkaline alcohol was irradiated up to 1.5 KGy (0.15 Mrad) with gamma rays from a Co-60 source in the presence or absence of oxygen. The irradiated wood meals were washed thoroughly with fresh water, air dried and cooked under the ordinary cooking conditions. The results are summarized as follows: (1) Pre-irradiation in aqueous alkali have negligible effect on kraft cooking. (2) In the case of ethanol addition (50 g/l), pre-irradiation in vacuo shows acceleration of delignification and stabilization of carbohydrates during kraft cooking. Cooked yield gain by pre-irradiation was about 1.2 in all, over the range of delignification from 80 to 90%. Aqueous ethanol without alkali also shows positive but smaller effect than that with alkali. (3) Propanol, iso-propanol and butanol show positive but smaller effects than ethanol. However, methanol does not show any positive effect. (4) Irradiation in the presence of oxygen does not show any attractive effect on kraft cooking.

Immunomodulation of murine B16 melanoma metastasis: thymosin, thymectomy and irradiation

International Nuclear Information System (INIS)

Naylor, P.H.; Bhakoo, H.S.; Rosen, F.; Paolini, N.S.; Goldstein, A.L.

1983-01-01

Thymosin, a product of the endocrine system, was used to further define the effects of immunomodulation of metastasis. Adult thymectomized C57BL/6 mice, 4 wk post-irradiation (400 R) had a decrease in the number of pulmonary metastases (compared to controls) following tail vein injection of 5 X 10 4 B16 melanoma cells. Thymosin fraction 5 (fr. 5) administration (200 μg/mouse, 3 times weekly beginning 2 days post-thymectomy) returned the number of metastases to the nonthymectomized values. Thymosin treatment of sham-operated, sham-operated irradiated, or thymectomized nonirradiated mice did not significantly elevate the number of metastases compared to the respective controls. Variant tumors which have an increase in metastasis following thymectomy and irradiation were also used. Thymosin administration reversed the effects of thymectomy in such variants, resulting in a decrease in metastasis. Metastases in thymosin-treated control mice were not significantly altered. A role for the thymus in metastasis via an endocrine product (thymosin) is suggested by these studies. Since thymosin did not increase metastasis in intact mice with tumors, further clinical trials with thymosin in cancer patients are not counterindicated by the results. These experiments confirm that thymosin fr. 5 is an important probe of the immunoendocrine events involved in tumor growth and metastasis. (Auth.)

Progress on untargeted effects of ionizing irradiation

International Nuclear Information System (INIS)

Liu Jing; Chen Jihong; Li Wenjian

2010-01-01

The side effect of ionizing irradiation has been paid more attention with its widely using in tumor treating and mutation breeding. In recent years, untargeted effects induced by ionizing irradiation have become a hotspot of radiobiology. Here, according to reported results, we reviewed the types (genomic instability, bystander effect and adaptive response) and mechanisms of untargeted effects of ionizing irradiation in this paper. (authors)

Basal cell carcinoma treated with MTDQ and irradiation

International Nuclear Information System (INIS)

Pollak, Z.; Fodor, J.; Erdelyi, V.; Bihari, O.; Eckhardt, S.

1979-01-01

Patients with basal cell carcinoma of the skin were treated with combined MTDQ (6,6'-methylene-bis-(2,2,4-trimethyl-1,2-dihydroquinoline)) adminstration and irradiation. Significantly better results were obtained with a skin exposure of 2000 R combined with MTDQ than with the same dose alone. The results were comparable to those obtained with an exposure of 4000 R. MTDQ adminstration induced disease of tissular malonaldehyde concentration and suggested the peroxide-decomposing action of the radiation sensitizer. (Auth.)

Effects of mediastinal irradiation on oesophageal function

Energy Technology Data Exchange (ETDEWEB)

Yeoh, E.; Holloway, R.H.; Russo, A.; Tippett, M.; Bermingham, H.; Chatterton, B.; Horowitz, M. [Royal Adelaide Hospital, SA (Australia)

1996-02-01

Although it is well recognised that oesophageal symptoms are common during therapeutic irradiation of intrathoracic malignant diseases, the effects of mediastinal irradiation on oesophageal function are poorly defined. To clarify the pathogenesis of these sequelae a prospective study was performed to document comprehensively the effects of mediastinal irradiation on oesophageal function. Oesophageal symptoms, barium swallow, endoscopy, and combined radionuclide scintigraphy and oesophageal manometry were evaluated in eight patients with potentially curable intrathoracic malignant disease before treatment, during the last week of mediastinal irradiation, and six to eight weeks after its completion. Before irradiation, structural abnormalities were excluded by barium swallow and endoscopy. All but one patient experienced odynophagia or dysphagia, or both, during mediastinal irradiation (p<0.001) but endoscopic abnormalities were observed in only three patients and there was no correlation between oesophageal symptoms and endoscopic changes. Irradiation, however, had no significant effect on oesophageal motility or transit. It is concluded that oesophageal symptoms which develop during mediastinal irradiation are not a result of altered oesophageal motility or transit and may reflect increased mucosal sensitivity. (author).

A comparative study of total body irradiation as a method of inducing granulocyte depletion in mice

International Nuclear Information System (INIS)

Bogman, M.J.J.T.; Cornelissen, I.M.H.A.; Berden, J.H.M.; Jong, J. de; Koene, R.A.P.

1984-01-01

Since conventional methods of inducing depletion of polymorphonuclear granulocytes (PMNs) in mice, such as treatment with cytostatic drugs and anti-PMN sera, proved to be insufficient to induce a stable PMN depletion for several days, and were accompanied by considerable toxic side effects, we induced neutrophil depletion in mice by total body irradiation (TBI) in a single dose of 6.0 Gy (600 rads.) at a dose rate of 0.20 Gy/min. This treatment reduced the number of PMNs in the peripheral circulation to values below 150/μl from day 3-10 after irradiation. The number of lymphocytes fell simultaneously. Platelet counts remained above 60% of normal values during the first 7 days after irradiation. Complement levels were not significantly affected by TBI. The results show that TBI of 6.0 Gy induces pronounced and stable PMN depletion in mice for at least 7 days. Furthermore, under an aseptic regimen the mice can be kept in good condition and losses are less than 5%. (Auth.)

Conceptual design of a conveyor system for the Philippine multipurpose cobalt-60 gamma irradiation facility

International Nuclear Information System (INIS)

Borras, A.M.

1992-01-01

The Multipurpose Cobalt-60 Gamma Irradiation Facility at the PNRI presently utilizes the batch irradiation method using turntables to rotate the product boxes. The target materials or products are being carried manually or with the use of pushcart through the personnel maze. This paper presents a conceptual design for the best suitable product-handling or conveyor system for the Philippine Multipurpose Cobalt-60 Gamma Irradiation Facility. The main irradiation conveyor line shall be a 55 cm x 200 cm slat-type conveyor made of SUS 304 material that could be operated in a semi-batch continuous flow and/or shuffle-dwell method with a tact-time range of 10 min to 7 h. The products can be irradiated in a single direction, two-pass, two-sided method. (auth.). 11 refs.; 4 figs.; 2 tabs

Effective suppression of bystander effects by DMSO treatment of irradiated CHO cells

International Nuclear Information System (INIS)

Kashino, Genro; Prise, K.M.; Suzuki, Keiji

2007-01-01

Evidence is accumulating that irradiated cells produce some signals which interact with non-exposed cells in the same population via a bystander effect. Here, we examined whether dimethyl sulfoxide (DMSO) is effective in suppressing radiation induced bystander effects in Chinese hamster ovary (CHO) and repair deficient xrs5 cells. When 1 Gy-irradiated CHO cells were treated with 0.5% DMSO for 1 hr before irradiation, the induction of micronuclei in irradiated cells was suppressed to 80% of that in non-treated irradiated cells. The suppressive effect of DMSO on the formation of bystander signals was examined and the results demonstrated that 0.5% DMSO treatment of irradiated cells completely suppressed the induction of micronuclei by the bystander effect in non-irradiated cells. It is suggested that irradiated cells ceased signal formation for bystander effects by the action of DMSO. To determine the involvement of reactive oxygen species on the formation of bystander signals, we examined oxidative stress levels using the 2',7'-dichlorofluorescein (DCFH) staining method in irradiated populations. The results showed that the treatment of irradiated cells with 0.5% DMSO did not suppress oxidative stress levels. These results suggest that the prevention of oxidative stress is independent of the suppressive effect of DMSO on the formation of the bystander signal in irradiated cells. It is suggested that increased reactive oxygen species (ROS) in irradiated cells is not a substantial trigger of a bystander signal. (author)

Influence of irradiation conditions on the gamma irradiation effect in polyethylene

International Nuclear Information System (INIS)

Kacarevic-Popovic, Z.; Gal, O.; Novakovic, L.J.; Secerov, B.

2002-01-01

Complete text of publication follows. The radiation cross-linking of polyethylene, due to its high cross-linking yield, has resulted in the radiation technology that has found application in radiation production of heat shrinkable structures and in improvement of mechanical and thermo-physical properties of oriented polyethylene objects. It is observed that the cross-linking efficiency decreases when the irradiation is carried out in the presence of oxygen. In order to estimate the conditions that improve cross-linking efficiency, gamma irradiation effect in two types of polyethylene, irradiated in water and air was investigated. The polyethylene samples used were the low density (LDPE) Lotrene CdF 0302 with 45% crystallinity and the high density (HDPE) Hiplex EHM 6003 with 73% crystallinity. Both kinds of samples, fixed in the Pyrex glass tubes, were simultaneously irradiated with 60 Co gamma rays in distilled water and air, at a doses rate of 9,5 kGy/h (determined by the Fricke dosimeter) at room temperature. Radiation induced oxidative degradation was followed through oxygen containing group formation by the carbonyl group band (1720 cm -1 ) and transvinylene group formation by the band at 966 cm -1 in the infrared spectra. Cross-linking efficiency was determined by gel content using the procedure of the extraction in xylene. The monitored effects of gamma irradiation in water and air point to the conclusion that irradiation in water leads to the lower oxidative degradation and higher cross-linking compared with the effects measured after irradiation in air

Radiobiological considerations in the treatment of neuroblastoma by total body irradiation

International Nuclear Information System (INIS)

Wheldon, T.E.; O'Donoghue, J.; Gregor, A.; Livingstone, A.; Wilson, L.; West of Scotland Health Boards, Glasgow

1986-01-01

Neuroblastoma is a radiosensitive neoplasm for which total body irradiation (TBI) is presently under clinical consideration. Collated data on the radiobiology of human neuroblastoma cells in vitro indicates moderate cellular radiosensitivity and low capacity for accumulation of sublethal damage. Mathematical studies incorporating these parameters suggest that low dose fractionated TBI is unlikely to achieve significant levels of tumour cell kill. When high dose TBI is used in conjuction with bone marrow rescue a tumour 'log cell kill' of 4-5 should be achievable. This effect would be additional to that acheived by chemotherapy. Fractionated TBI with bone marrow rescue may be curative for some patients in clinical remission who are presently destined to relapse. (Auth.)

Polymerization of impregnated monomer in wood by microwave irradiation

International Nuclear Information System (INIS)

Kawase, Kaoru; Hayakawa, Kiyoshi

1976-01-01

The manufacturing of a wood-plastic combination (WPC) by irradiation of microwave (2,450 and 915 +- 50 MHz) or gamma-ray was carried out. After the impregnation of dry woods (Hinoki: Chamaecyparis obtusa Endl., Buna: Acer mono Maxim., and Kaede: Fagus crenata Blume) with the mixture of the vinyl monomers and chemical reagents, the monomer in wood was polymerized by irradiation. In case of polymerization with microwave (2,450 MHz) the effect of oxygen was not recognized, but in the case of gamma-ray the rate of polymerization remarkably decreased in the presence of oxygen. The polymerization of various monomers was carried out also in the air, and the conversions of styrene, methyl-, ethyl-, n-propyl-, and n-butyl-methacrylate were 51.8 -- 89.1%, but that of vinyl acetate was lower (4.3 -- 8.2%). The conversion of monomers with irradiation of 915 MHz microwave was very low (2.6 -- 33.5%). The conversion of monomers increased when toluylene diisocyanate was added in the monomers. The percentage of extraction with hot benzene of WPC (chip) decreased by the addition of toluylene diisocyanate. It was concluded from C.H.N. analyses that the reaction took place among the wood, toluylene diisocyanate and methyl methacrylate. (auth.)

Economic feasibility of food irradiation in the Philippines

International Nuclear Information System (INIS)

Singson, C.C.; De Guzman, Z.M.; Pasion, W.B.

1991-01-01

Food irradiation is not a new technology and is accepted in many countries. Market acceptance of irradiated foods is established and the importance of radiation to reduce post-harvest food losses, increase shelf-life and improve hygienic quality of foods has been recognized in Asia and the Pacific. Countries with strict quarantine restrictions, such as the United States and Japan, require treatment of fresh fruits and produce for insect pests disinfestation. Several studies have established the technical feasibility of using radiation to preserve some food items in the country such as mangoes, onions, garlic, black pepper, coffee, prawns and desiccated coconut. The aim of this study is to determine the feasibility of setting up an irradiation facility in the Philippines, to undertake the processing of selected food items especially those with good export potentials, to identify areas of concern vital to the success or failure of this type of undertaking and to make recommendations to enhance the viability of this project. (auth.). 13 refs.; appendices; 6 tabs

Unirradiated UO2 in irradiated zirconium alloy sheathing

International Nuclear Information System (INIS)

MacDonald, R.D.; Hardy, D.G.; Hunt, C.E.L.; Scoberg, J.A.

1979-07-01

Zircaloy-clad UO 2 fuel elements have defected in power reactors when element power outputs were raised significantly after a long irradiation at low power. We have irradiated fuel elements fabricated from fresh UO 2 pellets and zirconium alloy sheaths previously irradiated without fuel. This gave a fuel element with radiation-damaged low-ductility sheathing but with no fission products in the fuel. The elements were power boosted in-reactor to linear power outputs up to 84 kW/m for two five-day periods. No elements defected despite sheath strains of 0.82 percent at circumferential ridge postions. Half of these elements were subsequently soaked at low power to build up the fission product inventory in the fuel and then power boosted to 63 kW/m for a third time. Two elements defected on this final boost. We conclude that these defects were caused by fission product induced stress-corrosion cracking and that this mechanism plays an importent role in power reactor fuel defects. (auth)

Thermal/hydraulic bowing stability analysis of grid-supported multi-pin bundles with differential swelling and irradiation creep

International Nuclear Information System (INIS)

McAreavey, G.

1977-01-01

Azimuthal variations of clad temperature in fuel pin bundles leads to pin bowing by differential thermal expansion. During irradiation in a fast flux further possibly more severe bowing is caused by differential neutron induced voidage swelling, which, being temperature sensitive, will also vary azimuthally. The problem of pin bowing in a fuel element cluster involves consideration of the thermal/hydraulic behaviour, allowing for both inherent and induced clad temperature non-uniformities, coupled with the restrained bowing behaviour, including differential thermal expansion, differential swelling, and irradiation creep. All pins must be considered simultaneously. In the temperature and stress ranges of interest thermal creep may be neglected. An existing computer code, IAMBIC solves the zero time thermal bowing problem for a cluster of up to 61 pins on hexagonal pitch, with up to 21 supports at arbitrary axial spacing. The present paper describes the basis of TRIAMBIC, a time dependent code which analyses the irradiation induced effects in fuel pin bunbles due to fast neutrons. (Auth.)

Effects of irradiation on the vascularity of lung

Energy Technology Data Exchange (ETDEWEB)

Fujiwara, K; Takegawa, Y; Nagase, M; Akiyama, H [Tokushima Univ. (Japan). School of Medicine

1975-06-01

Effects of irradiation on the intravascular volume of the lung were studied with respect to changes in intravascular volume over a period of time after irradiation, the effect of fractionation of the dose and the influence of the irradiation dose rate. After a single irradiation with 1000 rad or 3000 rad, applied locally to the lung, the intravascular volume decreased significantly in 1 to 3 months after irradiation. The changes in the intravascular volumes of lungs could be lessened by fractionation of the dose or by low dose rate irradiation.

Irradiation effect on animal feeds and feedstuffs

International Nuclear Information System (INIS)

Kume, Tamikazu

1983-10-01

Aiming to secure the safety of animal feeds and develop the new resources, the effect of γ-irradiation on disinfection and the changes in components were investigated. Salmonellae and coliforms contaminating in animal feeds and feedstuffs were eliminated by 0.5 -- 0.6 Mrad and 0.5 -- 0.8 Mrad, and osmophilic moulds were sterilized by 0.7 -- 0.75 Mrad. From these results, it is concluded that the dose for disinfection of animal feeds is 0.8 Mrad. The main components were hardly changed by irradiation up to 5 Mrad, and the component changes in irradiated samples could be suppressed during storage while the components in unirradiated samples were markedly changed with the growth of osmophilic moulds. Histamine and lysinoalanine, which may cause the feed poisoning, were never accumulated in feedstuffs by irradiation. The nutritional value of chick feeds was not changed by 1.0 Mrad irradiation. From these results, it is considered that no problem for wholesomeness of animal feeds occurs by irradiation. Therefore, the irradiation is effective for disinfection and keeping the nutritional value of animal feeds during storage. Irradiation promotes the recovery of proteins in the wastewater by coagulation of proteins and improves the property of coagulants due to the degradation of polysaccharides. These results indicate that irradiation is effective to develop the new resources for animal feeds. (author)

Gastrointestinal decontamination in healthy and lethally irradiated monkeys

International Nuclear Information System (INIS)

Hendriks, W.D.H.

1980-01-01

In periods of extreme immunosuppression, infections which are often life-threatening, frequently occur. In an attempt to prevent such infections in lethally irradiated rhesus monkeys, the animals were subjected to strict reverse isolation prior to irradiation and administrated orally with nonabsorbable antibiotics in order to eliminate their microflora. The antibiotic combination was selected on the basis of a sensitivity test and was added to the liquid food supply. To rapidly achieve a high bactericidal concentration in the intestine, the same antibiotics were additionally given orally for 5 days. The microflora was reduced rapidly; within a few days sterile cultures were obtained. Particularly after discontinuation of the administration of the additional antibiotics were colonizations found. In contrast to colonizations persisting from the first day of treatment on, the first were rather easy to suppress. (Auth.)

Induction and repair of strand breaks and 3'-hydroxy terminals in the DNA of mouse brain following gamma irradiation

International Nuclear Information System (INIS)

Yoshizawa, K.; Furuno, I.; Yada, T.; Matsudaira, H.

1978-01-01

DNA was isolated from mouse brain after in vivo γ-ray irradiation, treated with endonuclease S 1 from Aspergillus oryzae if necessary, and analysed further by alkaline and neutral sucrose gradient centrifugation. In parallel, its template activity was determined by DNA polymerase (EC 2.7.7.7, enzyme A of Klenow from Escherichia coli) assay as described previously. Similar experiments were performed with cultured mouse leukaemia cells (L5178Y) irradiated in vitro at 0 0 C. (Auth.)

Purification and physicochemical properties of α-amylase from irradiated wheat

International Nuclear Information System (INIS)

Machaiah, J.P.; Vakil, U.K.

1981-01-01

α-Amylases from control and gamma-irradiated (at 0.2 and 2.0 kGy dose levels) wheat seedlings were purified to homogeneity and characterized. The molecular weight of the enzyme from a 2 kGy irradiated sample was slightly lower than that of the control; other general and catalytic properties also showed some differences. α-Amylase from the irradiated (2kGy) sample had a narrow range of pH optimum and was inactivated faster at alkaline pH and by heat treatment than the enzyme from unirradiated wheat. A high apparent Michaelis constant (Ksub(m)) and a low maximal velocity (Vsub(max)) for the hydrolysis of soluble starch catalyzed by the enzyme from irradiated (2kGy) wheat, suggested some modifications in the formation of the substrate α-amylase complex. Further, of the total number of amino acid residues lost on irradiation, dicarboxylic amino acids constituted the largest percentage; these structural alterations in the enzyme may be responsible for its partial inactivation. The total sugars liberated upon amylolysis of starch with the 2kGy irradiated enzyme were lower than control, and there was accumulation of higher maltodextrins in the place of maltose. (auth.)

Effects of CO, O2, NO, H2O, and irradiation temperature on the radiation-induced oxidation of SO2

International Nuclear Information System (INIS)

Tokunaga, Okihiro; Nishimura, Koichi; Suzuki, Nobutake; Washino, Masamitsu

1977-01-01

When a SO 2 -H 2 O-O 2 -N 2 gaseous mixture was irradiated by electron beams of 1.5 MeV, SO 2 was easily oxidized to H 2 SO 4 . Effects of CO, O 2 , NO, H 2 O, and irradiation temperature on the radiation-induced oxidation of SO 2 were studied by measuring the SO 2 concentration gas chromatographically. The G(-SO 2 ) increased greatly at the addition of a small amount of O 2 , and then decreased gradually with an increase in the O 2 concentration, i.e., the G(-SO 2 ) values were 0.9, 8.0, and 5.3 for the 0, 0.1, and 20% O 2 concentrations at 100 0 C, respectively (Fig.4). The G(-SO 2 ) was independent of the H 2 O concentration in the range of 0.84 to 8.4% (Fig.5). The G(-SO 2 ) decreased with a rise in the irradiation temperature (Fig.6) and an apparent activation energy of the oxidation reaction of SO 2 obtained was -4.2 kcal.mol -1 . The effects of CO, NO, and O 2 on the G(-SO 2 ) showed that SO 2 was mainly oxidized by OH and O and that the contribution of OH to the oxidation of SO 2 increased with an increase in the O 2 concentration (Table 1). The rate constants for the reactions of SO 2 with OH and O, obtained from competitive reactions of SO 2 with CO and O 2 , were 5.4 x 10 11 cm 3 .mol -1 .sec -1 and 5.0 x 10 11 cm 3 .mol -1 .sec -1 , respectively. (auth.)

A summary of recent developments in the sludge irradiation program at Sandia laboratories

International Nuclear Information System (INIS)

Morris, M.E.; Sivinski, J.S.; Brandon, J.R.; Neuhauser, K.S.; Ward, R.L.

1978-01-01

Sandia Laboratories has shifted the emphasis of its Sewage Sludge Irradiation Program toward treating dried sewage sludges rather than liquid sludges for the following reasons: (1) cities' interests in composting sewage sludge before final disposal; (2) need for disinfection of the product before sale to the public; and (3) low cost of disinfection by radiation processing. As a result of this shift, the Sandia Irradiator for Dried Sewage Solids (SIDSS), was designed and is near completion. The irradiator will treat up to 8 tons/day of solids with a 1 megarad absorbed dose. A bucket conveyor will transport the sewage sludge past a 1 megacurie cesium-137 γ-ray source. If a lower dose than 1 megarad is acceptable for disinfection, the daily throughput of the irradiator will be correspondingly increased. The irradiator is designed so that the cesium-137 γ-ray sources used to charge the facility can be manipulated underwater. After source unloading is complete, the water will be drained and the irradiator will be operated dry. Either bagged or bulk solids can be irradiated with the system. (Auth.)

Effects of ion beam irradiation on semiconductor devices

Energy Technology Data Exchange (ETDEWEB)

Nashiyama, Isamu; Hirao, Toshio; Itoh, Hisayoshi; Ohshima, Takeshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1997-03-01

Energetic heavy-ion irradiation apparatus has been developed for single-event effects (SEE) testing. We have applied three irradiation methods such as a scattered-ion irradiation method, a recoiled-atom irradiation method, and a direct-beam irradiation method to perform SEE testing efficiently. (author)

Effect of irradiation on foodstuffs Pt. 4

International Nuclear Information System (INIS)

Kluender, U.; Boegl, W.

1980-01-01

In the present study of the relevant literature the results of irradiation experiments with 32 foodstuffs have been compiled and discussed. This study is intented to give a survey on chemical changes in irradiated food, and neither microbiological nor toxicological and physiological aspects were taken into account. The results published by the authors of the original papers have been compiled in form of a dictionary which contains all important data such as radiation source, irradiation conditions, treatment and characteristics of the sample, investigation methods, results of the chemical and organoleptical changes etc. In addition, the effects of irradiation both on individual food substances and individual groups of foodstuffs have been summarized. Furthermore, the effects of irradiation on sensory characteristics and the atmospheric influence during irradiation are given seperately. The last chapter contains a comparison between the chemical changes of food due to irradiation treatment and those caused by conventional methods. The final discussion of the results will be published seperately. (orig./MG) [de

Effects of fission neutrons and X-rays on the epithelium of the mouse stomach

International Nuclear Information System (INIS)

Kingma-ter Haar, J.M.

1982-07-01

A quantitative study is presented of the effects of whole-body irradiation on the stomach of mice. Two types of ionizing radiation were compared - fast fission neutrons of 1.0 MeV mean energy and 300 kVp X-rays. The effects on the functional cell populations, on gastric secretion and on gastric stem cell populations were studied. These effects have been investigated a) for a neutron dose in the lethal dose-range of 4.0 Gy as a function of time and b) at a post-irradiation interval of 3 weeks as a function of neutron and X-ray dose. (Auth.)

Ion beam irradiation effects on aromatic polymers

International Nuclear Information System (INIS)

Shukushima, Satoshi; Ueno, Keiji

1995-01-01

We studied the optical and thermal properties of aromatic polymer films which had been irradiated with 1 MeV H + , H 2 + and He + ions. The examined aromatic polymers were polyetherether ketone(PEEK), polyetherimide(PEI), polyether sulfon(PES), polysulfon(PSF), and polyphenylene sulfide(PPS). The optical densities at 300nm of PES and PSF greatly increased after the irradiation. The optical densities at 400nm of all the examined polymer lineally increased with the irradiation dose. The PEEK film which had been irradiated with 1 MeV H + was not deformed above melting point. This demonstrates that cross-linking occurs in PEEK films by ion beam irradiation. As for the effects, depending on the mass of the irradiated ions, it was found that the ions with a high mass induced larger effects on the aromatic polymers for the same absorption energy. (author)

The involvement of nuclear nucleases in rat thymocyte DNA degradation after γ-irradiation

International Nuclear Information System (INIS)

Nikonova, L.V.; Nelipovich, P.A.; Umansky, S.R.

1982-01-01

Possible mechanisms of internucleosomal DNA fragmentation in thymocytes of irradiated rats were studied. It was shown that thymocyte nuclei contain at least two nucleases that cleave DNA between nucleosomes - a Ca 2+ /Mg 2+ -dependent nuclease and an acidic one which does not depend on bivalent ions. 2 and 3 h after irradiation at a dose of 10 Gy the initial rate of DNA cleavage by Ca 2+ /Mg 2+ -dependent nuclease in isolated nuclei increased three and seven times, respectively, but the kinetics of DNA digestion by acidic nuclease did not change. The experiments with cycloheximide indicated that Ca 2+ /Mg 2+ -dependent endonuclease turns over at a high rate. The activity of the cytoplasmic acidic and Mg 2+ -dependent nucleases was shown to increase (by 40 and 50%, respectively) 3h after irradiation. The effect is caused by the de novo synthesis of the nucleases. At the same time the activity of nuclear nucleases did not essentially change. The chromatin isolated from rat thymocytes 3 h after irradiation did not differ in its sensitivity to some exogenic nucleases (DNAase I, micrococcal nuclease and nuclease from Serratia marcescens) from the control. Thus, Ca 2+ /Mg 2+ -dependent endonuclease seems to be responsible for the postirradiation internucleosomal DNA fragmentation in dying thymocytes. (Auth.)

Low temperature irradiation facility at Kyoto University Reactor (KUR)

International Nuclear Information System (INIS)

Atobe, Kozo; Okada, Moritami; Yoshida, Hiroyuki; Kodaka, Hisao; Miyata, Kiyomi.

1977-01-01

A new refrigeration system has been substituted to the low temperature irradiation facility at KUR instead of the previous one, since April in 1975. The model 1204 CTi He liquifier was designed to be modified for the refrigerator with the capacity of 30 watts at 10 K. The refrigeration capacity of 38 watts at 10 K was defined using a special cryostat and transfer-tubes, and the lowest temperature of about 18 K was measured using the irradiation loop without reactor operation. The reconstructed facility enables us to hold the many specimens simultaneously in the sample chamber of the irradiation loop at about 25 K during reactor operation of 5 MW. The irradiation dose has been reached about 6.6 x 10 16 n sub(f)/cm 2 and 6.1 x 10 17 n sub(th)/cm 2 with the normal reactor operation cycle of up to 77 hours. The stable operation condition of the machine and the special safety system for the refrigeration system enable us to maintain easily the facility with a constant operation condition for such a long time irradiation. Many kinds of low temperature neutron irradiation experiments are carried out using the facility, which techniques are partially reported. (auth.)

Food irradiation and its biological effects

International Nuclear Information System (INIS)

Shah, Alok; Nanjappa, C.; Chauhan, O.P.

2014-01-01

Irradiation of foods drew attention mostly in 1960s for disinfestation of food grains, spices and sprout inhibition in mainly potato and onion. γ-irradiation at 0.25 to 1 kGy dosage levels are usually used for irradiating grains, legumes, spices and sprout-prone vegetables. Irradiation of foods with in permissible dosage levels of 0.25 to 5 kGy is usually considered fairly safe from human consumption point of view not withstanding usual health concerns about its usage in foods. Irradiation of foods, in mostly solid or semi-solid form, at 5 kGy levels of γ-irradiation can achieve radicidation or, radiation equivalent of pasteurization and, if γ-irradiation is used at 10 kGy, it can achieve radappertization or, radiation equivalent of thermal commercial sterilization. However, the food industry uses γ-irradiation at 0.25 to 2 kGy only for mostly disinfestation of food grains/legumes, spices, sprout inhibition in potato and onion and, for surface sanitation of frozen fish, poultry and meat. Exposure to irradiation creates free radicals in foods that are capable of destroying some of the spoilage and pathogenic microflora but the same can also damage vitamins and enzymes besides creating some new harmful new chemical species, called unique radiolytic products (URPs), by combining with certain chemicals that a food may be laced with (like pesticides/fungicides). Exposure to high-energy electron beams are also known to create deleterious biological effects which may even lead to detection of trace amounts of radioactivity in the food. Some possible causes delineated for such harmful biological effects of irradiation include: irradiation induced vitamin deficiencies, the inactivity of enzymes in the foods, DNA damage and toxic radiolytic products in the foods. Irradiation, a non-thermal food preservation technique, has a role in salvaging enormous post harvest losses (25-30%) in developing economies to increase the per capita availability of foods. (author)

Studies on the formation of volatile amines from trimethylamine oxide by gamma-irradiation, (1)

International Nuclear Information System (INIS)

Uchiyama, Sadao; Kondo, Tatsuo; Uchiyama, Mitsuru

1976-01-01

The fundamental investigation concerning the formation of volatile amines from trimethylamine oxide (TMAO) by gamma-irradiation was carried out as a model of the irradiation of fish-meat products like Kamaboko. By the irradiation of 5.8 Mrad, 5 x 10 -6 mol of dimethylamine (DMA) was produced from 1 x 10 -4 mol of TMAO in a phosphate buffer (pH 6.5). Fe 2+ , Fe 3+ , Zn 2+ and Al 3+ promoted the formation of amines but Ca 2+ , Mg 2+ and Na + scarcely affected it. On the other hand, cysteine, which is known as a protecting agent against gamma-ray, promoted the formation of DMA. However, protain worked repressibly for amine formation even when Fe 3+ was contained. (auth.)

Study of irradiation effect on curcuma polyphenols

International Nuclear Information System (INIS)

Rejeb, Imen

2008-01-01

The present study was carried out to evaluate the effect of gamma irradiation on curcumin (Curcuma Longa rhizome) component, particularly the polyphenolic fraction. Powdered rhizome was irradiated at 0, 5, 10 and 15 KGy (dose rate of 6 KGy / H). Polyphenolics were extracted and total polyphenols conent (TPC) was quantified using the Folin-Ciocalteau method. The irradiation effect was also evaluated by the HPLC technique. The chromatographic analysis showed that the irradiated and non-irradiated curcumin spectrum gave similar data. The antioxidant and antibacterial activities of the phenolic extracts were also assessed. the anti oxidative potential of the sample was evaluated using two radical scavenging methods with DPPH and ABTS. The antimicrobial analysis showed that the phenolic extracts of curcumin inhibited the growth of the studied microorganisms. Our results showed that irradiated samples were not affected in terms of polyphenols content and characteristics. (Author)

Neutron irradiation effects in pressure vessel steels and weldments

Energy Technology Data Exchange (ETDEWEB)

Ianko, L [International Atomic Energy Agency, Vienna (Austria). Div. of Nuclear Power; Davies, L M

1994-12-31

This paper deals with the effects of neutron irradiation on the steel and welds used for the pressure vessels which house the reactor cores in light water reactors: irradiation effects on mechanical properties and the shift in ductile-brittle transition temperature, importance of the knowledge of the neutron fluence and of the monitoring and surveillance programmes; empirical and mechanistic modelling of irradiation effects and the necessity of data extension to new operational limits; consequences on the manufacturing and structural design of materials and structures; mitigation of irradiation effects by annealing; international activities and programmes in the field of neutron irradiation effects on PV steels and welds. 37 refs., 22 figs.

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

In-reactor precipitation and ferritic transformation in neutron-irradiated stainless steels

International Nuclear Information System (INIS)

Porter, D.L.; Wood, E.L.

1979-01-01

Ferritic transformation (γ→α) was observed in type 304L, 20% cold-worked AISI 316, and solution-annealed AISI 316 stainless steels when subjected to fast neutron irradiation. Each material demonstrated an increasing propensity for transformation with increasing irradiation temperature between 40 and 550 0 C. Irradiation-induced segregation of Ni solute to precipitates was found not to be a controlling factor in the transformation kinetics in 304L. Similar composition data from 316 materials demonstrates a much greater dependence of matrix Ni depletion by precipitation reactions during neutron irradiation. The 316 data establishes a strong link between such depletion and the observed γ→α transformation. Moreover, the lack of correlation between precipitate-related Ni depletion and the γ→α transformation in 304L can be related to the fact that irradiation-induced voids nucleate very quickly in 304L steel during irradiation. These voids present competing sites for Ni segregation through a defect drag mechanism, and hence Ni segregates to voids rather than to precipitates, as evidenced by observed stable γ shells around voids in areas of complete transformation. (Auth.)

The effect of γ-irradiation on changes of blood chemistry in RC-MAP after irradiation

International Nuclear Information System (INIS)

Hirose, Tetsuhito; Katayama, Norifumi; Okamoto, Yukiharu; Tsuda, Tadaaki; Ota, Kiichiro; Nishioka, Shingo; Tsumura, Michiyo; Yukawa, Mariko

1997-01-01

Irradiation to transfused blood is obligated to prevent from post transfusion graft-versus-host disease (PT-GVHD) by inactivation of lymphocytes. The rule of irradiated dose was not determined, it's dose being ranged from 15 to 50 Gy, but it's dose was done by each institute. We investigated an adequate dose of irradiation to blood on effects of plasma Na, potassium (K), Chloride (Cl), LDH, GOT, BUN and total protein (T.P) after irradiation of transfused blood. By comparison of plasma Na and K in non-irradiated blood, plasma K was increased and decreased in a parallelism of period of stored irradiated blood, two days after it's irradiation. Effects of Na and K levels were dose dependent. LDH level was increased in a time-dependency, but not by it's dose plasma Cl, LDH, GOT, BUN and T.P levels were not influenced. Our results indicated that the mechanism of RBC permeability after irradiation seemed to be inactivated Na-K ATPase activity in RBC cell membrane. (author)

Quantitative analysis of the gas evolved from high polymers in γ-irradiation

International Nuclear Information System (INIS)

Arakawa, Kazuo; Hayakawa, Naohiro; Kuriyama, Isamu

1977-09-01

Polymers are used as insulator of cables in nuclear-reactor radiation field. To estimate the evolution of gases when irradiated, total gas yield and composition were measured for variety of polymers. Samples were irradiated at room temperature in vacuo with 60 Co-γ rays. For ethylene propylene rubber (EPR), irradiation in high-temperature steam was also made. Composition of the gas was determined with a mass spectrometer. G-value of the total gaseous product was 3.2 to 3.4 for low-density polyethylene (LDPE) and 2.5 to 2.7 for high-density polyethylene (HDPE). In both polyethylene, hydrogen gas predominated. When an anti-radiation oil was added to LDPE, gas evolution was reduced drastically. For chloro-sulfonated PE (Hypalon), SO 2 gas was one of the major products even when the polymer contained only about 1% of sulfonyl groups. G-value of the total gas for EPR irradiated in high-temperature steam was 3.1, regardless of the temperature. (auth.)

In-reactor measurement of clad strain: effect of power history

International Nuclear Information System (INIS)

Fehrenbach, P.J.; Morel, P.A.

1980-01-01

A series of experimental irradiations has been undertaken at CRNL to measure directly the in-reactor deformation of fuel elements while they are operating at power. Power histories have been chosen to allow investigation of power, time at power and burnup on pellet-clad interaction for element linear powers to 60kW/m. Results are presented which indicate that irradiation of a fresh fuel element at high power is effective in minimizing clad hoop stresses during subsequent ramps or cycles to that power. The effectiveness of this preconditioning appears to be due primarily to fuel densification rather than stress relaxation in the clad. (auth)

Effect of irradiation on sweet corn preservation

International Nuclear Information System (INIS)

Fu Junjie

2002-01-01

60 Co γ-ray was used to irradiate newly-harvested sweet corn and the results showed that the effects of irradiation on soluble solids, sucrose, starch and total sugar were not significant. The viscosity of starch decreased with the increasing of irradiation dose. The preservation duration of irradiated sweet corn was 7 days longer than that of CK, and the sweet, smell, taste of sweet corn had no abnormal change

A method for the selective β-irradiation of individual lymphocyte microcultures and its application in a preliminary study of radiation sensitivity

International Nuclear Information System (INIS)

Webb, C.; Sheldon, P.

1984-01-01

A method that permits high-energy β-irradiation to be applied to individual lymphocyte microplate cultures is described. The principle involves the introduction of single energy sources (in this case 32 P) contained within tubes which rest inside wells containing the lymphocyte cultures. Cell viability and mitogen-induced transformation were studied under these conditions. Dose-response effects were clearly demonstrated. The method is simple and, provided the precautions described are adhered to, safe. It should be applicable to studies of radiation sensitivity of putative target cells in various clinical situations. (Auth.)

Effect of x-ray irradiated rat fetus mandible

International Nuclear Information System (INIS)

Han, Chang Gun; You, Dong Soo

1978-01-01

The effect of irradiation of x-ray to developing rat mandible in the gestation stage was focused on the study of mandible development and the side effect of x-ray irradiation. The author studied the effect of x-ray irradiation with the gestated rat and their offsprings. 100 rads, 200 rads, 300 rads and 400 rads of x-ray was irradiated in regular order schematically at the lower left abdomen of gestated rat. 18 1/2 days after conception, their offsprings were sacrificed and examined their developing mandible with histological findings. The results were as followed. 1. In the 100-200 rads irradiated rat offsprings, bony trabeclulation was revealed irregular shape. In combine with this finding, osteoblast and fibroblast were appeared shrunken of their nucleus and location of eccentric position. 2. In the 300-400 rads irradiated rat offsprings, decrease of fibroblast and osteoblast appearance in the periosteum were prominently observed and empty lacunae were frequently appeared in their bone matrix. 3. The advent of osteoclast and resorption of cortical bone were appeared in proportion to increasing of x-ray irradiation.

Appearance of thymic nurse cells after gamma irradiation

International Nuclear Information System (INIS)

Mulder, A.H.; Bekkum, D.W. van

1983-01-01

Since prothymocytes home from the bone marrow to the thymus, it was tested in the mouse whether prothymocytes could be recaptured from thymic nurse cells (TNC). Bone marrow cells were labelled with the red fluorescing anthracycline daunomycin and varying numbers (up to 25 x 10 6 nucleated bone marrow cells) were injected into lethally irradiated recipients. At several time intervals after transplantation (up to 24 hours), thymuses were removed and the TNCs were isolated. No specific red fluorescence was found within the TNCs. These experiments were repeated with supravital compounds at concentrations which have been shown not to affect viability, homing pattern and function. Again, no specific fluoresence was found in the TNC after transplantation of labelled bone marrow into irradiated mice. The relationship between the dose of total body gamma irradiation and the time after irradiation was investigated. Maximal numbers of TNCs were found at 6 hours after irradiation with 4 Gy. Eight to 12 hours after irradiation, the number of TNCs isolated decreased and had returned to preirradiation levels at 24 hours. The relation between TBI dose and the number of TNCs per thymus is shown. The number determined at 3 hours increased with the dose to reach a maximum at 4 Gy. The authors later studied the morphology of the TNCs isolated at 4 to 6 hours after irradiation. On electron microscopic examination, signs of degeneration and death of the enclosed thymocytes was detected. (Auth.)

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish

International Nuclear Information System (INIS)

Smith, Richard W.; Seymour, Colin B.; Moccia, Richard D.; Mothersill, Carmel E.

2016-01-01

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent on

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish

Energy Technology Data Exchange (ETDEWEB)

Smith, Richard W., E-mail: rich.wilson.smith@gmail.com [Department of Animal Biosciences, University of Guelph, Guelph, Ontario (Canada); Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada); Seymour, Colin B. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada); Moccia, Richard D. [Department of Animal Biosciences, University of Guelph, Guelph, Ontario (Canada); Mothersill, Carmel E. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada)

2016-02-15

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent on

Irradiation induced effects in zirconium (A review)

International Nuclear Information System (INIS)

Madden, P.K.

1975-06-01

Irradiation creep in zirconium and its alloys is comprehensively discussed. The main theories are outlined and the gaps between them and the observed creep behaviour, indicated. Although irradiation induced point defects play an important role, effects due to irradiation induced dislocation loops seem insignificant. The experimental results suggest that microstructural variations due to prior cold-working or hydrogen injection perturb the irradiation growth and the irradiation creep of zircaloy. Further investigations into these areas are required. One disadvantage of creep experiments lies in their duration. The possibility of accelerated experiments using ion implantation or electron irradiation is examined in the final section, and its possible advantages and disadvantages are outlined. (author)

Effect of gamma radiation on glucose and sodium chloride solutions for injection

International Nuclear Information System (INIS)

Lakoza, G.N.; Grigor'eva, O.L.; Mart'yanova, B.M.; Vorob'eva, E.N.; Kuznetsova, R.M.

1976-01-01

Irradiation of 40% glucose solution with 0.5-4.0 Mrads di not affect the detoxicating properties of glucose or its ability to raise blood sugar levels. Such doses had no effect on the toxicological properties of 40% glucose solution and on 0.9% sodium chloride solution. The biological and physicochemical properties of 40% solution and 0.9% sodium chloride solutions irradiated with sterilizing doses showed no significant alterations during storage for one and three years, respectively. It is concluded that the solutions studied may be sterilized by radiation. (auth.)

Electron migration in hydrated biopolymers following pulsed irradiation at low temperatures

International Nuclear Information System (INIS)

Lith, D. van.

1987-01-01

Charge migration in biopolymer-water mixtures and the effect of water concentration on the charge migration is investigated by measuring the electrical conductivity and the light emission with the pulse radiolysis technique. A preliminary account of the microwave conductivity observed in hydrated DNA and collagen at low temperature after pulsed irradiation is given. The results show that when hydrated DNA or collagen are irradiated at low temperatures, conductivity transients with microsecond lifetime are observed. It is tentatively concluded that these transients are due to the highly mobile dry electron. The effect of water concentration on mobility, lifetime and migration distance of the electron is discussed. The effect of additives to the hydrated systems on the behaviour of the electron is described. It is shown that the observed effects of the additives confirm the earlier conclusions that the dry electron is the species responsible for the radiation induced conductivity. The water concentration in the DNA- and collagen-systems could be varied only between zero and approximately fifty percent, due to inhomogeneities which occur at higher water concentrations. Experiments on gelatin, a biopolymer which forms homogeneous samples with levels of hydration varying from almost zero to 100% water (ice) are described. Both the radiation induced and the dark microwave conductivity have been studied as a function of water content. Preliminary results of a study of the light emission from pulse irradiated DNA-water mixtures are reported in an attempt to establish a relation between the observed electron migration and the formation of excited states via charge neutralization. (Auth.)

Effect of irradiation on functional properties of Gum Tragacanth

Directory of Open Access Journals (Sweden)

Neda Mollakhalili meybodi

2017-03-01

Full Text Available Background and objective: irradiation is a physical treatment in which products are exposed to ionized radiation such as gamma and x rays to improve the security and quality. Hydrocolloids are components that are used in food science to improve texture properties. Exposing to irradiation treatment may change structural and functional properties. By regard to the importance of irradiation on decontaminating of hydrocolloids in food application, the aim of this study is studying the effect of irradiation at different doses on functional properties of Gum Tragacanth in food application. Material and methods: effect of irradiation treatment was studied on the rheological properties, zeta potential, particle size distribution and surface tension of dispersion systems contained 0/5% w/ w gum tragacanth that is irradiated at different doses (0, 0.75. 3, 5 kGy. The effect of irradiation on rheological properties was monitored by rheometer. In order to monitor the effect of irradiation treatment on particle size distribution, zeta potential and surface tension, particle sizer, Brookhaven zeta plus and tensiometer sere used respectively. All treatments were performed three times and the data were analyzed by one way ANOVA. Significant differences between means were identified (P values < 0.05 using Duncan test. Results: Irradiation, change rheologiacal properties and particle size distribution of dispersion contained gum tragacanth. Irradiation treatment up to 0.75 kGy increase zeta potential, but irradiating at higher doses decrease it again. Results of studying parameters showed that irradiation changes the functional properties by affecting on structure. These changes depend on irradiation dose Conclusion: Gum tragacanth irradiation may improve the functional properties by affecting on structure.

Failure of the capsule for coated particles irradiation

International Nuclear Information System (INIS)

Yamaki, Jikei; Nomura, Yasushi; Nagamatsuya, Takaaki; Yamahara, Takeshi; Sakai, Haruyuki

1975-10-01

During operation cycle No. 27 of the JMTR (Japan Material Testing Reactor) on May 20, 1974, leakage of the fission product gas occurred from the capsule 72F-7A, which contained coated particles for the irradiation; the coated particles are for the development of a multi-purpose high temperature gas cooled reactor. The capsule was designed for heat 1600 0 C. Three nickel plates as the heat reflector were sandwiched in between the plates of titanium and zirconium, which were adsorbents for the impurity gases in the cladding tube (Nb-1%Zr). Temperatures of the plates were about 1000 0 C under the irradiation, so one metal diffused into the other metal through interfaces, resulting in the formation of an alloy. Its melting point was lower than those of metals in the capsule. The cladding material Nb-1%Zr was melted by the alloy and finally a pin hole developed through the cladding. The process of failure, design of the capsule, post-irradiation test of the capsule and the failure-reproducing experiment with a mock-up capsule are described. (auth.)

Calculation of flux density distribution on irradiation field of electron accelerator

International Nuclear Information System (INIS)

Tanaka, Ryuichi

1977-03-01

The simple equation of flux density distribution in the irradiation field of an ordinary electron accelerator is a function of the physical parameters concerning electron irradiation. Calculation is based on the mean square scattering angle derived from a simple multiple scattering theory, with the correction factors of air scattering, beam scanning and number transmission coefficient. The flux density distribution was measured by charge absorption in a graphite target set in the air. For the calculated mean square scattering angles of 0.089-0.29, the values of calculation agree with those by experiment within about 10% except at large scattering angles. The method is applicable to dose evaluation of ordinary electron accelerators and design of various irradiators for radiation chemical reaction. Applicability of the simple multiple scattering theory in calculation of the scattered flux density and periodical variation of the flux density of scanning beam are also described. (auth.)

Irradiation of liquid manure for the purpose of utilization in agriculture

International Nuclear Information System (INIS)

Simon, J.; Gleria, M. di; Szemeredi, Gy.

1980-01-01

The authors give an account of the use of ionizing radiation for disinfection of swine liquid manure. The most common representatives of pathogenic and facultative pathogenic microorganisms of swine liquid manure have been irradiated and their sensitivity to different doses of 60 Co has been examined. The microorganisms proved to be more resistant to irradiation in culture media than in swine liquid manure, where most of the studied bacteria were killed by radiation dose of 4 kGy. However, a very high resistance has been found at the saprophytic and pathogenic mycobacteria and at the spore containing Clostridium perfringens having required a lethal dose of 10 and 15 kGy respectively. After radiation-treatment the liquid manure can be used in agriculture for irrigation and it can be recycled to the stall cleaning procedures. The use of irradiated liquid manure as a possible animal food is also discussed. (Auth.)

Effects of irradiation on color and lipid oxidation of prosciutto

International Nuclear Information System (INIS)

Kong Qiulian; Qi Wenyuan; Yue Ling; Chen Zhijun; Bao Yingzi; Dai Xudong; Xu Yun

2012-01-01

This study dealt with the effect of irradiation on the color, irradiation odor and lipid oxidation of prosciutto crudo. The hams were irradiated by γ-ray and electronic beam (EB). Changes of color, irradiation odor, TBA value (TBARS), peroxide value (POV), carbonyl value and conjugated diene value were analyzed and compared with non-irradiated hams. Results showed that color index (a * ) of control, γ-ray irradiated and EB irradiated were 14.39, 9.45 and 11.71 respectively. The ratios of a * /b * were different with the type of rays. The ratio of a * /b * of EB irradiation was same with control, while that of γ-ray irradiation was decreased apparently. γ-ray irradiation had been shown to have apparently detrimental effect on the color and odor of hams, while EB irradiation had little detrimental effect. Irradiation increased POV and conjugated diene value, but the amounts of lipid oxidation products (TBARS, carbonyl value) were less than nonirradiated hams. (authors)

Postreplicational formation and repair of DNA double-strand breaks in UV-irradiated Escherichia coli uvrB cells

International Nuclear Information System (INIS)

Wang, Tzuchien V.; Smith, K.C.

1986-01-01

The number of DNA double-strand breaks formed in UV-irradiated uvrB recF recB cells correlates with the number of unrepaired DNA daughter-strand gaps, and is dependent on DNA synthesis after UV-irradiation. These results are consistent with the model that the DNA double-strand breaks that are produced in UV-irradiated excision-deficient cells occur as the result of breaks in the parental DNA opposite unrepaired DNA daughter-strand gaps. By employing a temperature-sensitive recA200 mutation, we have devised an improved assay for studying the formation and repair of these DNA double-strand breaks. Possible mechanisms for the postreplication repair of DNA double-strand breaks are discussed. (Auth.)

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

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.

Proton irradiation effects in silicon devices

Energy Technology Data Exchange (ETDEWEB)

Simoen, E; Vanhellemont, J; Alaerts, A [IMEC, Leuven (Belgium); and others

1997-03-01

Proton irradiation effects in silicon devices are studied for components fabricated in various substrates in order to reveal possible hardening effects. The degradation of p-n junction diodes increases in first order proportionally with the fluence, when submitted to 10 MeV proton irradiations in the range 5x10{sup 9} cm{sup -2} to 5x10{sup 11} cm{sup -2}. The damage coefficients for both p- and n-type Czochralski, Float-Zone and epitaxial wafers are reported. Charge-Coupled Devices fabricated in a 1.2 {mu}m CCD-CMOS technology are shown to be quite resistant to 59 MeV H{sup +} irradiations, irrespective of the substrate type. (author)

Proton irradiation effects on organic polymers

International Nuclear Information System (INIS)

Seguchi, T.; Sasuga, T.; Kawakami, W.; Hagiwara, M.; Kohno, I.; Kamitsubo, H.

1987-01-01

Organic polymer films(100 μm thickness) of polyethylene, polypropylene, polyethyleneterephtalate, and polyethersulfone were irradiated by protons of 8 MeV using a cyclotron, and their radiation effects were investigated by the changes of mechanical properties. In order to irradiate protons uniformly over wide area of polymer films, specimens were scanned during proton irradiation using a special apparatus. The absorbed dose was measured by CTA and RCD film dosimeters, and can be determined that 1 μC/cm 2 of 8 MeV proton fluence is equivalent to 54 kGy. For polyethylene and polypropylene, there was no significant difference between proton and electron irradiation for same doses. However, for polyethersulfone the decay of mechanical property was observed to be less than that of irradiation by electron. (author)

Two reactions method for accurate analysis by irradiation with charged particles

International Nuclear Information System (INIS)

Ishii, K.; Sastri, C.S.; Valladon, M.; Borderie, B.; Debrun, J.L.

1978-01-01

In the average stopping power method the formula error itself was negligible but systematic errors could be introduced by the stopping power data used in this formula. A method directly derived from the average stopping power method, but based on the use of two nuclear reactions, is described here. This method has a negligible formula error and does not require the use of any stopping power or range data: accurate and 'self-consistent' analysis by irradiation with charged particles is then possible. (Auth.)

Neutron irradiation effects on plasma facing materials

Science.gov (United States)

Barabash, V.; Federici, G.; Rödig, M.; Snead, L. L.; Wu, C. H.

2000-12-01

This paper reviews the effects of neutron irradiation on thermal and mechanical properties and bulk tritium retention of armour materials (beryllium, tungsten and carbon). For each material, the main properties affected by neutron irradiation are described and the specific tests of neutron irradiated armour materials under thermal shock and disruption conditions are summarized. Based on current knowledge, the expected thermal and structural performance of neutron irradiated armour materials in the ITER plasma facing components are analysed.

Neutron irradiation effects on plasma facing materials

International Nuclear Information System (INIS)

Barabash, V.; Federici, G.; Roedig, M.; Snead, L.L.; Wu, C.H.

2000-01-01

This paper reviews the effects of neutron irradiation on thermal and mechanical properties and bulk tritium retention of armour materials (beryllium, tungsten and carbon). For each material, the main properties affected by neutron irradiation are described and the specific tests of neutron irradiated armour materials under thermal shock and disruption conditions are summarized. Based on current knowledge, the expected thermal and structural performance of neutron irradiated armour materials in the ITER plasma facing components are analysed

Effect of irradiation spectrum on the microstructure of ion-irradiated Al2O3

International Nuclear Information System (INIS)

Zinkle, S.J.

1994-01-01

Polycrystalline samples of alpha-alumina have been irradiated with various ions ranging from 3.6 MeV Fe + to 1 MeV H + ions at 650 C. Cross-section transmission electron microscopy was used to investigate the depth-dependent microstructure of the irradiated specimens. The microstructure following irradiation was observed to be dependent on the irradiation spectrum. In particular, defect cluster nucleation was effectively suppressed in specimens irradiated with light ions such as 1 MeV H + ions. On the other hand, light ion irradiation tended to accelerate the growth rate of dislocation loops. The microstructural observations are discussed in terms of ionization enhanced diffusion processes

Effects of gamma irradiation on wheat quality

International Nuclear Information System (INIS)

Ozkaya, B.; Koksel, H.; Ozkaya, H.; Tutluer, H.

1994-01-01

Effect of gamma irradiation at the doses of 2.5,5.0,7.5,10.0 and 12.5 kGy on two bread wheat samples (Bezostaya and Gerek) with distinct physical and technological properties was investigated in this study.Irradiation at the levels used had no significant effect on the flour yields of both varieties.No apparent changes were observed in ash,protein and wet gluten contents of the irradiated samples and control.However,as the radiation level was increased the falling number and sedimentation values of the irradiated samples showed a steady decrease.Thiamine and riboflavin contents also decreased significantly with irradiation.Farinograph absorption increased with increasing radiation exposure.However, dough development time,stability and valorimeter values decreased as radiation levels increased.Maximum resistance to extension(Rm), resistance at constant deformation (R 5) and area(A) values of extensograms decreased in both varieties as radiation levels increased

A hypothetical stochastic mechanism of radiation effects in single cells: some further thoughts and results

International Nuclear Information System (INIS)

Puri, P.S.

1982-01-01

The author briefly describes a stochastic model for radiation effects in single cells, discusses some results based on this model and then raises several questions which need further attention. While the ultimate goal is to develop appropriate stochastic models of phenomena arising in irradiated experimental animals, the present concern however is limited to irradiation effects on cells of some homogeneous tissue. The basic assumptions underlying the stochastic model are presented. Some of the model implications are compared with empirical findings in the literature. The question of whether or not a primary particle of UV radiation generates any secondary particles is also considered. (Auth.)

Babesia divergens: protection of intact calves against heterologous challenge by the injection of irradiated piroplasms

International Nuclear Information System (INIS)

Lewis, D.; Purnell, R.E.; Brocklesby, D.W.

1980-01-01

Blood from a splenectomized calf infected with Babesia divergens was divided into 20 ml aliquots which were γ-irradiated at doses of 0, 24, 28, 32, 36 and 40 krad and then inoculated into groups of three intact calves. Animals receiving non-irradiated blood had typical mild B. divergens reactions, but those receiving irradiated blood had either very mild reactions or no overt reaction. When the calves were challenged with a similar number (7.5 X 10 9 ) of heterologous parasites of a recently-isolated field strain, those which had received blood irradiated at 0, 24, 28 and 32 krad were all immune whereas four of the five surviving animals which had received blood irradiated at 36 or 40 krad were susceptible. The immune status of individual cattle was reflected accurately in the results of the micro-ELISA test, which detected a significant rise in serum antibody titre of the four susceptible animals by day 21 after challenge. (Auth.)

Combined effect of formaldehyde and gamma-irradiation. Vitamin complex effect

International Nuclear Information System (INIS)

Ban'kovskij, A.A.; El'chaninova, M.A.

1996-01-01

Combined inhalation effect of formaldehyde and gamma-irradiation on the activities of alcohol and aldehyde dehydrogenases in rat lung tissue was studied. The possibility of fitting the parameters studied by the vitamin PP, A and E and complex was shown. At investigation of white rats in conditions of formaldehyde inhalation in concentration 10 mg/m 3 and gamma-irradiation by dose 0.25 Gy the changes of activities of alcohol and aldehyde dehydrogenases in the rat lung tissue were detected. An injection of PP, A and E vitamin complex after combined effect of formaldehyde and gamma-irradiation contributes to normalization of studied parameters. The K(C -1 ) constant is reduced. On this basis it is proposed that in such conditions formaldehyde stabilizes membranes and protects important metabolic processes against damages. Thus, vitamin complex is capable to level a toxic combined effect of formaldehyde and gamma-irradiation. 9 refs., 1 tab

Irradiation effects on perfluorinated polymers

International Nuclear Information System (INIS)

Lappan, U.; Geissler, U.; Haeussler, L.; Pompe, G.; Scheler, U.; Lunkwitz, K.

2002-01-01

Complete text of publication follows. High-energy radiation affects the properties of polymers by chain scission and crosslinking reactions. Both types of reaction occur simultaneously in irradiated polymers. However, one process will usually predominate, depending on the chemical structure of the polymer and the irradiation conditions such as temperature and atmosphere. Polytetrafluoroethylene (PTFE) undergoes predominantly chain scission, if the irradiation is performed at room temperature. This shortcoming is exploited by converting PTFE into low molecular weight micropowders. The use of PTFE micropowders functionalized with COOH groups as additive in polyamides to improve the sliding properties of the materials has been studied. During the compounding process in a twin screw extruder the COOH groups of the irradiated PTFE react with the polyamides. For these studies, it became necessary to investigate the content of end groups in irradiated PTFE by FTIR and 19 F solid-state NMR. These date were used to calculate number-average molecular weights. The ratios of COOH groups to CF 3 groups are discussed in terms of the mechanism of PTFE degradation. If PTFE is irradiated at temperatures above its crystalline melting point in an oxygen-free atmosphere, branching and crosslinking occur. The dependence of radiation effects on perfluorinated copolymers (FEP, PFA) on temperature has been studied. Melt flow index measurements have shown that branching and crosslinking predominate over chain scission with increasing irradiation temperature both in FEP and in PFA. Quantitative analysis of 19 F solid-state NMR data has shown that the content of branching groups (>CF-) exceeds the content of end groups in the case of PFA irradiated above its crystalline melting point. The formation of COF and COOH groups in the irradiated PFA is interpreted as a result of partial degradation of perfluorovinyl ether comonomer units

Effects of gamma irradiation on physiological effectiveness of Korean medicinal herbs

International Nuclear Information System (INIS)

Byun, Myung-Woo; Yook, Hong-Sun; Kim, Kyong-Su; Chung, Cha-Kwon

1999-01-01

Effects of gamma irradiation on the physiological effectiveness of Korean medicinal herbs were investigated. The physiological effectiveness including antioxidant and anticomplement function, nitrite scavenging and electron donating ability of Korean medicinal herbs by gamma irradiation at 10 kGy did not differ from that of the nonirradiated control

Recovery of the spermatogenetic epithelium in the mouse after irradiation with 1-MeV fission neutrons

International Nuclear Information System (INIS)

Aardweg, G.J.M.J. van den.

1983-01-01

In this thesis the recovery of the spermatogenetic epithelium in the mouse is studied after damage with 1-MeV fission neutrons. A severe depletion of A-spermatogonia and radiosensitive stem cells occurs after neutron irradiation. Recovery of the epithelium is initiated by surviving radioresistant stem cells giving rise to colonies, which grow into the empty seminiferous tubules. After discussing properties of normal and irradiated spermatogenetic epithelium, the growth and the differentiation of spermatogenetic colonies in the mouse testis after irradiation, as well as response and kinetics of colony-forming spermatogonial stem cells in CBA mice up to 30 weeks after a first neutron dose and recovery of the epithelium after a second irradiation are investigated. These four subjects are dealt with in separate papers. Finally, a discussion and a summary of these studies is presented. (Auth.)

Chromosome aberrations of the peripheral lymphocytes in rabbits exposed to single and fractionated whole-body x-irradiations

International Nuclear Information System (INIS)

Tamura, Hiroaki; Sakurai, Masaharu; Sugahara, Tsutomu.

1978-01-01

The changes in the frequency of peripheral lymphocytes with chromosome aberrations were observed during or after irradiation of rabbits exposed to fractionated or single whole-body irradiations. In rabbits given daily fractionated whole-body irradiations the incidence of the aberrations showed a linear increase in the first week; however, the incidence decreased thereafter though exposures were repeated. The lymphocyte count tended to decrease as the number of irradiations increased. In rabbits exposed to a single dose of 250 R or 500 R the incidence of aberrations rapidly decreased over a period of 10 days following irradiation, and then showed a little change thereafter. The lymphocyte count in the peripheral blood reached a nadir 2 - 5 days after irradiation, and then started to increase gradually. It was speculated that there are two types of lymphocytes, long-lived and short-lived, in the peripheral blood of rabbits, both of which are PHA-committed. (auth.)

Transformation of ultraviolet-irradiated human fibroblasts by simian virus 40 is enhanced by cellular DNA repair functions

International Nuclear Information System (INIS)

Hall, J.D.

1981-01-01

Human fibroblasts irradiated with ultraviolet light were either tested for survival (colony formation) or infected with simian virus 40 and examined for transformation (foci formation). For normal cell cultures, the fractions of surviving colonies which were also transformed increased with increasing irradiation dose. In contrast, little increase in the transformation of ultraviolet-irradiated repair-deficient (xeroderma pigmentosum and xeroderma pigmentosum variant) cells was observed. Similar experiments with xeroderma pigmentosum variant cells treated with caffeine following irradiation indicated that, under these conditions, the deficient cells produced more transformants among the survivors of ultraviolet irradiation than did unirradiated cells. These results suggest (1) that DNA repair functions, not DNA damage per se, are required for enhanced viral transformation in normal cells; (2) that functions involved in excision repair and functions needed for replication of ultraviolet-damaged DNA appear necessary for this stimulation; and (3) that blocking DNA replication in ultraviolet-irradiated xeroderma pigmentosum variant cells by caffeine enhances viral transformation. (Auth.)

Modifying effect of low dose irradiation

International Nuclear Information System (INIS)

Kalendo, G.S.

1989-01-01

It is shown that irradiation of Hela cells with stimulating doses of 0,1 Gy changes the cells' response to the subsequent radiation effect of greater value: instead of DNA synthesis inhibition stimulation takes place. Modifying effect of preliminary irradiation with 0,1 Gy manifests it self only in case if there is a certain time interval not less than 3 minutes and not more than 10 minutes (3-5 minutes is optimal interval). Data on modifying effect with 0,1 Gy at subcellular and cellular-population levels are presented. 21 refs.; 6 figs

Recovery in stages I and II of thermal and fission neutron irradiated molybdenum

International Nuclear Information System (INIS)

Coltman, R.R. Jr.; Klabunde, C.E.; Redman, J.K.

1975-01-01

The influence of initial dose and irradiation doping upon the recovery of Mo was studied for the markedly different types of damage produced by thermal and fission neutrons. The features of the Stage I recovery commonly seen for several fcc metals can be identified, including a I/sub D/ peak at 40 0 K. The typical dose-dependent behavior of a I/sub E/ subpeak was observed at approximately 47 0 K, and evidence for free interstitial migration is further supported by irradiation doping results. Stage II shows a first-order peak at 120 0 K in which the population percentage increases with increasing initial dose in opposite fashion to fcc impurity detrapping peaks. (auth)

Immunization with irradiated larvae against Dictyocaulus filaria in young lambs

International Nuclear Information System (INIS)

Dhar, D.N.; Sharma, R.L.

1981-01-01

In the lungworm-endemic areas of Kashmir, 6-10 week old lambs of Karnah and Kashmir Merino breeds were vaccinated with two doses of 50 kR gamma-irradiated larvae of Dictyocaulus filaria, given a month apart. Assessed on the basis of reduced prevalence and significantly lower faecal larval output over an eight-month observation period, vaccinated lambs showed a high degree of resistance to naturally acquired D. filaria infection. The results also show that vaccination against D. filaria provided some degree of protection against infection with other lungworm species. (Auth.)

Effects of irradiation upon spices

Energy Technology Data Exchange (ETDEWEB)

1978-04-01

ESR studies were performed on untreated and irradiated samples of paprika powder, ground black pepper, and a spice mixture of the following composition: paprika, 55%; black pepper, 14%; allspice, 9%; coriander, 9%; marjoram, 7%; cumin, 4%; and nutmeg, 2%. Gamma radiation doses from 0.5 to 5 Mrad were applied. In the case of paprika samples, the effect of moisture content on the formation and disappearance of radiation-induced free radicals was also investigated. Shortly after irradiation (on the day of radiation treatment) high amounts of free radicals were detected in irradiated spice samples but they diminished upon storage. After a period of 3 months the ESR signals of the irradiated samples approximated those of the controls. The free radicals found in unirradiated ground spices did not disappear during a storage period as long as one year. The formation and disappearance of radiation-induced free radicals were found to be strongly affected by the moisture content of samples. If a sample of low moisture content containing a high free radical concentration after irradiation was placed in an atmosphere of higher moisture content, the free radicals decayed rapidly.

Effect of irradiation on the Porphyromonas gingivalis

Energy Technology Data Exchange (ETDEWEB)

Lee, Chang Hee; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [School of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

2008-03-15

The aim of this study was to observe a direct effect of irradiation on the periodontopathic Porphyromonas gingivalis (P. gingivalis). P. gingivalis 2561 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Changes in viability and antibiotic sensitivity, morphology, transcription, and protein profile of the bacterium after irradiation were examined by pour plating method, disc diffusion method, transmission electron microscopy, RT-PCR, and immunoblot, respectively. Viability of irradiated P. gingivalis drastically reduced as irradiation dose was increased. Irradiated P. gingivalis was found to have become more sensitive to antibiotics as radiation dose was increased. With observation under the transmission electron microscope, the number of morphologically abnormal cells was increased with increasing of irradiation dose. In RT-PCR, decrease in the expression of fim A and sod was observed in irradiated P. gingivalis. In immunoblot, change of profile in irradiated P. gingivalis was found in a number of proteins including 43-kDa fimbrillin. These results suggest that irradiation may affect the cell integrity of P. gingivalis, which is manifested by the change in cell morphology and antibiotic sensitivity, affecting viability of the bacterium.

Effect of irradiation on the Porphyromonas gingivalis

International Nuclear Information System (INIS)

Lee, Chang Hee; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2008-01-01

The aim of this study was to observe a direct effect of irradiation on the periodontopathic Porphyromonas gingivalis (P. gingivalis). P. gingivalis 2561 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Changes in viability and antibiotic sensitivity, morphology, transcription, and protein profile of the bacterium after irradiation were examined by pour plating method, disc diffusion method, transmission electron microscopy, RT-PCR, and immunoblot, respectively. Viability of irradiated P. gingivalis drastically reduced as irradiation dose was increased. Irradiated P. gingivalis was found to have become more sensitive to antibiotics as radiation dose was increased. With observation under the transmission electron microscope, the number of morphologically abnormal cells was increased with increasing of irradiation dose. In RT-PCR, decrease in the expression of fim A and sod was observed in irradiated P. gingivalis. In immunoblot, change of profile in irradiated P. gingivalis was found in a number of proteins including 43-kDa fimbrillin. These results suggest that irradiation may affect the cell integrity of P. gingivalis, which is manifested by the change in cell morphology and antibiotic sensitivity, affecting viability of the bacterium.

Synergistic effects of irradiation of waste water

International Nuclear Information System (INIS)

Woodbridge, D.D.; Cooper, P.C.; Vandenburg, A.J.; Musselman, H.D.; Lowe, H.N.; Florida Inst. of Tech., Melbourne; Army Facilities Engineering Support Agency, Fort Belvoir, Va.

1975-01-01

Theoretical considerations of the use of high level radiation in the treatment of waste water have failed to consider the effects of the hydrated electron and the potential of possible synergistic effects of combining chlorine, oxygen, and irradiation. An extensive testing program at the University Center for Pollution Research of Florida Institute of Technology over the past four years has shown that irradiation of waste water samples immersed in an aqueous environment provide bacterial kill and reduction in organic pollution far greater than that obtained from theoretical considerations of G values and earlier experiments where the waste samples were not immersed in an aqueous environment. These testing programs have investigated the synergistic effects of combining oxygen and irradiation. Each of these combined treatments resulted in an increased bacterial kill factor. Tests on Staphylococcus aureus bacteria and fecal streptococcus bacteria indicate that the synergistic effects observed for fecal coliform bacteria also apply to the pathogenic bacteria. A statistical analysis of the data obtained shows the interrelationships between the various effects on the bacteria. A definite shielding factor due to the turbidity of the waste water has been shown to exist. Synergistic effects have been shown to significantly offset the shielding effects. Optimization of these synergistic effects can greatly increase the effectiveness of irradiation in the treatment of waste water. (orig.) [de

Radioresistance and immunization effectiveness under internal irradiation

International Nuclear Information System (INIS)

Kal'nitskij, S.A.

1978-01-01

The effect of preliminary immunization on the radioresistance of mice to internal irradiation from incorporated 137 Cs or 90 Sr was studied, and it was found that a preliminary single immunization with bacterial vaccines had a favorable effect on the outcome of radiation injury. The present results suggested that vaccination had a very pronounced radioprotective effect and so may be used as a means of biologic protection from internal irradiation

Dried gamma-irradiated sewage solids use on calcareous soils: crop yields and heavy metals uptake

International Nuclear Information System (INIS)

McCaslin, B.D.; Sivinski, J.S.

1980-01-01

The fertilizer values of gamma-irradiated digested sewage solids (RDSS) and gamma-irradiated undigested sewage solids (RUSS) have been examined on calcareous soils. Previously published data from Sandia Laboratories have shown that approximately 1 mega-rad of gamma-irradiation effectively destroys pathogenic bacteria, parasites and plant seeds in dried sewage solids. Greenhouse experiments directly comparing gamma-irradiated and non-irradiated undigested and digested dried sewage solids as fertilizers indicate little or no effect of 1 mega-rad gamma radiation treatment on plant yield or plant-nutrient uptake and demonstrated considerable benefit from using sewage solids on calcareous soils. Plant response to undigested sewage solids was considerably greater than to digested sewage solids when applied at levels that were isonitrogenous. The calcareous soils in New Mexico typically range in pH from 7.5 to 9.0, limiting the plant-availability of many elements, especially heavy metals. Soils irrigated with sewage-effluent for 40 years demonstrated beneficial use of supplied plant-nutrients with no apparent increase in plant-uptake of heavy metals. RDSS applied to a calcareous soil low in plant-available iron increased plant growth in the greenhouse considerably more than treatments with equal amounts of nitrogen, phosphorus and iron applied as common fertilizer materials. Plant tissue concentrations of Fe, Zn, Mn and Cu showed that RDSS was a good source of these nutrients. Results also indicated that the total soluble salt concentration of the RDSS was the factor most limiting plant growth. Chromium, Cd, Ni and Pd plant-tissue concentrations were apparently not increased by RDSS treatments. (Auth.)

Effects of irradiation on color and lipid oxidation of prosciutto

International Nuclear Information System (INIS)

Kong Qiulian; Qi Wenyuan; Yue Ling; Chen Zhijun; Bao Yingzi; Dai Xudong; Xu Yun

2011-01-01

This study dealt with the effect of irradiation on the color, ordor and lipid oxidation of prosciutto crudo. The hams were irradiated by γ-ray and electronic beam (EB). Changes of color, ordor, TBA value (TBARS), peroxide value (POV), carbonyl value and conjugated diene value were analyzed and compared with nonirradiated hams. Results showed that color index (a * ) of control, γ-ray irradiated and EB irradiated were 14.39, 9.45 and 11.71 respectively. γ-ray irradiation had been shown to have apparently detrimental effect on the color and ordor of hams, while EB irradiation had little detrimental effect. Irradiation increased POV and conjugated diene value, but the amounts of lipid oxidation products (TBARS, carbonyl value) were less than nonirradiated hams. (authors)

Induction of resistance to rice tungro virus disease in rice cultivar Pusa 2-21 through irradiation

International Nuclear Information System (INIS)

Mathur, S.C.; Rao, M.; Prakash, Jitendra

1979-01-01

The dry seeds of Pusa 2-21, a moderately resistant rice cultivar, were subjected to 10, 15 and 20 Krad (dose rate 12.3 Krad/min) radiation dosages of gamma rays to induce resistance against rice tungro virus disease. The height of M 1 seedling was significantly reduced in 15 and 20 Krad treatments. However, there was no effect of gamma irradiation on seed germination. A limited population of M 2 and M 3 generation was screened at the rate of 3 viruliferous leafhoppers/seedling using single plant caging technique. In M 2 generation 22.0, 17.6 and 25.0 percent seedlings exhibited green colour (symptomless) representing resistant reaction to the disease in 10, 15 and 20 Krad treatments, respectively. Out of 1470 seedlings in M 3 generation, 2.7 percent seedlings showing no symptoms of tungro could be isolated indicating the possibility of inducing higher degree of resistance than that of the parent to RTV through irradiation for the first time. (auth.)

Studies on cross-immunity among syngeneic tumors by immunization with gamma-irradiated tumor cells

International Nuclear Information System (INIS)

Ito, Izumi

1977-01-01

In order to clarify whether cross-immunity among 3-methyl-cholanthrene (MCA)-induced sarcomas in C3H/He mice can be established or not, transplantations of syngeneic tumors were carried out in mice immunized with gamma-irradiated (13,000 rad 60 Co) tumor cells and in those immunized with living tumor cells thereafter. The following results were obtained. By using immunizing procedure with only gamma-irradiated tumor cells, a pair of tumors originating from one and the same mouse showed cross-resistance to each other. However, no such evidence was seen among tumors originating from different mice. Cross-immunity among syngeneic tumors originating from different mice could be clearly observed, when immunizing procedure using living tumor cells was added after the treatment with gamma-irradiated tumor cells. It was considered that common antigenicity among MCA-induced sarcoma cells was decreased by gamma-irradiation and that individual differences of tumor antigenecity were shown distinctly under such conditions. (auth.)

Radiation effects on the species-specific cell sorting-out of the cellular slime molds

International Nuclear Information System (INIS)

Satow, Takashi

1976-01-01

The effects of gamma-rays irradiation on the development and the species-specific cell sorting-out of the cellular slime mold, Dictyostelium discoideum, were investigated. The interphase amoebae of the organism showed extremely resistant to 60 Co gamma-rays. The percentage of non-stained cells estimated by dye staining method was more than 90% at the dose of 270 kR. The amoebae irradiated at 270 kR performed the development similar in the most respects to that of the un-irradiated amoebae except that a little portion of the fruiting bodies were abnormal and that the appearance of aggregates and slugs delayed 3 hrs. The ability of the species-specific cell sorting-out was not affected by gamma-rays irradiation at 270 kR. (auth.)

Radioprotective effect of exogenic hypoxia in fractionated irradiation

International Nuclear Information System (INIS)

Kazymbetov, P.; Yarmonenko, S.P.; Vajnson, A.A.

1988-01-01

During the experiments with mice it is established, that exogenic hypoxia protective effect (8%O 2 ), evaluated according to survival rate, decreases at the change from single to fractionated irradiation. Dose change factor (DCF) is equal to 1.55 and 1.22-1.31, respectively. Skin protection using exogenic hypoxia at the local fractionated irradiation is expressed more, than at the fractionated one. DCF is equal to 1.56 and 1.28, respectively. Exogenic hypoxia protection effect in the tumor is expressed rather weakly. DCF at single and fractionated irradiation constitutes 1.03 and 1.07-1.13, respectively. Due to skin preferential protection the therapeutic gain factor at irradiation under the exogenic hypoxia conditions constitutes 1.24 and 1.38-1.46, respectively, at single and fractionated irradiation

Comparison of sensitivity of repair-proficient and repair-deficient strains of Bacillus subtilis to ultraviolet irradiation and hydrogen peroxide

International Nuclear Information System (INIS)

Bayliss, C.E.; Shah, J.; Waites, W.M.

1982-01-01

Dormant bacterial spores are very resistant to irradiation with ultraviolet (UV) light. The authors have shown that simultaneous treatment with far-UV (254 nm) and hydrogen peroxide in a kill up to 2000-fold greater than that produced by irradiation either alone or followed by treatment with hydrogen peroxide. UV irradiation of hydrogen peroxide produces free hydroxyl radicals which are particularly lethal to microorganisms but free radical quenchers fail to protect spores against simultaneous UV and hydrogen peroxide. It is possible, therefore, that another mechanism is responsible for this synergistic killing. In this study the resistance was examined to simultaneous treatment with UV and hydrogen peroxide of a mutant of Bacillus subtilis which forms UV-sensitive spores. (Auth.)

Modification of genetic effect of gamma irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1985-01-01

The effect of direct electric current of different value and polarity on genetic sequences of γ-irradiation of Vicia faba seedlings has been studied. The previously found modifying effect of direct electric current is confirmed. The extent and character of this effect depend on the value and polarity of current as well as time between irradiation and electric effects. Current effect modes having no effect on irradiated seedlings protecting cells from injury and the modes aggravating radiation effect have been found. At certain modes the effects of direct electric current on irradiated seedlings changes in the rearrangement spectrum are observed, particularly the number of bridges is increased

Effects of irradiation on platelet function

International Nuclear Information System (INIS)

Rock, G.; Adams, G.A.; Labow, R.S.

1988-01-01

Current medical practice involves the irradiation of blood components, including platelet concentrates, before their administration to patients with severe immunosuppression. The authors studied the effect of irradiation on in vitro platelet function and the leaching of plasticizers from the bag, both immediately and after 5 days of storage. The platelet count, white cell count, pH, glucose, lactate, platelet aggregation and release reaction, and serotonin uptake were not altered by the irradiation of random-donor or apheresis units with 2000 rads carried out at 0 and 24 hours and 5 days after collection. The leaching of di(2-ethylhexyl)phthalate from the plastic bags followed by the conversion to mono(2-ethylhexyl)phthalate was not increased by irradiation. Therefore, it is possible to irradiate platelet concentrates on the day of collection and subsequently store them for at least 5 days while maintaining in vitro function. This procedure could have considerable benefit for blood banks involved in the provision of many platelet products

Elective brain irradiation in patients with small-cell carcinoma of the lung: preliminary report

International Nuclear Information System (INIS)

Katsenis, A.T.; Karpasitis, N.; Giannakakis, D.; Maragoudakis, N.; Kiparissiadis, P.

1982-01-01

The brain is a common site of metastases in small-cell carcinoma of the lung. Prophylactic brain irradiation with doses of 4000-4500 rads in 3-4 weeks appears to decrease the occurrence of brain metastases although it does not prevent this completely. In a group of patients with small-cell carcinoma of the lung and without evidence of brain metastases, the authors review the site and extent of the primary, the methods of treatment, the techniques of brain irradiation, and the relapses rate in relation to the status of the primary and the rate of brain metastases in another group without prophylactic brain irradiation. They further attempt to investigate combined modalities of treatment which would prolong life and prevent neurological complications in the small number of long survivors with small-cell carcinoma of the lung. (Auth.)

Mutagenic effect of cyclophosphan on bone marrow cells of irradiated rats

International Nuclear Information System (INIS)

Barkan, R.S.; Yakovleva, T.K.

1979-01-01

The frequency of chromosome aberrations in bone marrow cells of male rats was studied 24 hours after the intraperitoneal injection of cyclophosphane (25 mg/kg weight). Cyclophosphane (CP) was injected to animals that had been earlier (15 days before, 1, 3, 4, 6 and 9 months earlier) exposed to X-ray and γ-irradiation at the dose of 400 rad. It has been shown that the preliminary irradiation of animals results in a higher mutagenic CP effect as against its effect for non irradiated rats. The effect was recorded during four months following the acute single x-irradiation (dose rate of 70 rad/min) and within one month following chronic γ-irradiation (dose rate of 100 rad/day). At later periods, the above effect fully disappeared. Chronic irradiation was less effective with regard to the subsequent mutagenic CP action than the acute irradiation. In most experiments with acute irradiation an increase in mutagenic CP efficiency revealed itself both in an increase in the frequency of cells with chromosome aberrations and in the cell damage rate. The possible mechanisms of the effect of preliminary irradiation on the subsequent mutagenic effect of chemical compounds are discussed

Irradiation growth in zirconium alloys: a review

International Nuclear Information System (INIS)

Fidleris, V.

1980-09-01

The change in shape during irradiation without external stress, irradiation growth, was first discovered in uranium and later in graphite, zirconium and other core materials which exhibit anisotropic physical properties. The direction of maximum growth of metals invariably corresponds with the direction of minimum thermal expansion. In polycrystalline zirconium alloys growth is positive in the direction of maximum deformation during fabrication and in other directions it can be either positive or negative depending on the preferred orientation of grains (crystallographic texture). Growth increases gradually with temperature between 300 K and 620 K and rapidly with fluence up to about 1 x 10 25 n.m. -2 (Eμ1 MeV). At higher fluences the growth appears to saturate in annealed materials and reach a steady rate approximately proportional to dislocation density in cold-worked materials. Above 600 K both annealed and cold-worked materials have similar steady growth rates. Irradiation growth is caused by the segregation to different sinks of the vacancies and interstitials generated by irradiation, but the dominant types of sinks for each type of point defect and the mode of transport of the point defects to sinks cannot therefore be predicted theoretically. For the purpose of designing reactor core components empirical equations have been derived that can satisfactorily predict the steady state growth behaviour from texture and microstructure. (auth)

Gamma irradiation effects in optical fibres, splitters, and connectors

Directory of Open Access Journals (Sweden)

Srećković Milesa Ž.

2017-01-01

Full Text Available The paper presents a brief overview of contemporary ELION techniques with stress on their use for material modification and dosimetry. In the attempt to avoid some common misjudges of irradiation effects, special attention is paid to exact definition of irradiation geometry and careful adjustment of dose rates, which enable a proper elaboration of experimental results. In particular, effects of g-rays irradiation on properties of commercial optical fibres, splitters, connectors, and fibre joints are examined, which enables monitoring of irradiation effects in complex configurations made of materials with different radiation hardness (resistance. It has been established that g-rays irradiation of the investigated elements influences, in different ways, the transmission of laser beam signals of various wavelengths, under different modulation regimes. After irradiation, the signal attenuation is noticeably larger, both in optical connectors and optical splitter, than before it, and the effect increases in time. The effects are more pronounced at the 99 % than at the 1 % Y-splitter output at both measured wavelengths, and are more pronounced at 1310 nm than at 1550 nm. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III43009 and Grant no. III45012

Genetic effects of heavy ion irradiation in maize and soybean

International Nuclear Information System (INIS)

Yatou, Osamu; Amano, Etsuo; Takahashi, Tan.

1992-01-01

Somatic mutation on leaves of maize and soybean were observed to investigate genetic effects of heavy ion irradiation. Maize seeds were irradiated with N, Fe and U ions and soybean seeds were irradiated with N ions. This is a preliminary report of the experiment, 1) to examine the mutagenic effects of the heavy ion irradiation, and 2) to evaluate the genetic effects of cosmic ray exposure in a space ship outside the earth. (author)

Studies on combination effects of peplomycin and x-ray irradiation

International Nuclear Information System (INIS)

Munenaga, Yasuichi

1984-01-01

In order to study effects and methods of combination of peplomycin (PEP) and x-ray irradiation, inhibitory effects on DNA synthesis were investigated with synchronized cells from the parotid gland of mice treated with isoproterenol (IPR) and inhibitory effects on cell proliferation were investigated with Ehrlich solid tumor cells. PEP had dose-dependent effects on the inhibition of DNA synthesis and on the prolongation of cell cycles in the IPR-treated mouse cells. When 3.0 and 5.0 mg/kg of PEP were combined with 200 rad of x-ray irradiation at the early phase of G 1 , synergistic effects on the inhibition of DNA synthesis were seen. This was most noted in the group with PEP 30 minutes before irradiation. PEP had also dose-dependent inhibitory effects on the proliferation of Ehrlich solid tumor cells. This was increased when x-ray irradiation was combined with PEP. Inhibitory effects on the proliferation of tumor cells were greater when PEP was given before x-ray irradiation than after x-ray irradiation, regardless of the amount. The greatest effect was seen in the group with PEP 30 minutes before irradiation, as well as in the experiment with IPR-treated mouse cells. (Namekawa, K.)

Characterisation of irradiation effect on geo-polymers

International Nuclear Information System (INIS)

Chupin, Frederic

2015-01-01

This study aims to improve knowledge about the radiation effect on geo-polymer behavior in terms of dihydrogen release and general strength in order to consider them as an alternative to usual nuclear waste cementitious coating matrices. Using various characterization techniques (nitrogen adsorption, low temperature DSC, FTIR and 1 H NMR spectroscopy) and by means of simulation irradiations (gamma, heavy ions), it has been shown that all the water present in the geo-polymer could be radiolyzed and that there was a confinement effect on the water radiolysis under low LET irradiation, probably due to efficient energy transfers from the solid matrix to the interstitial solution. Three dihydrogen production rates have been identified with the absorbed dose, depending on the concentration of dissolved dioxygen and the dihydrogen accumulation in the geo-polymer matrix. The good mechanical strength of the geo-polymer has been shown up to 9 MGy under gamma irradiation and is due to its high stability under irradiation. This could be explained by the fast recombination of the defects observed by EPR spectroscopy. However, phase crystallization was revealed during irradiation with heavy ions, which may induce some weakening of the geo-polymer network under alpha irradiation. The overall results helped to understand the phenomenology in a waste package under storage conditions. (author) [fr

Molecular events associated with increased regenerative capacity of the goldfish retinal ganglion cells following X-irradiation: decreased level of axonal growth inhibitors

International Nuclear Information System (INIS)

Rachailovich, I.; Schwartz, M.

1984-01-01

In our previous work we established conditions to study the contribution of non-neuronal cells to the process of goldfish optic nerve regeneration. This issue has been studied successfully by adapting the use of X-irradiation to manipulate division of non-neuronal cells associated with the injured nerve. The regenerative capacity of the goldfish retinal ganglion cells was determined subsequent to the X-ray treatment. The authors present an analysis of the molecular events associated with regeneration and enhanced regenerative capacity which follows X-irradiation. (Auth.)

Genetic effects of feeding irradiated wheat to mice

International Nuclear Information System (INIS)

Vijayalaxmi

1976-01-01

The effects of feeding irradiated wheat in mice on bone marrow and testis chromosomes, germ cell numbers and dominant lethal mutations were investigated. Feeding of freshly irradiated wheat resulted in significantly increased incidence of polyploid cells in bone marrow, aneuploid cells in testis, reduction in number of spermatogonia of types A, B and resting primary spermatocytes as well as a higher mutagenic index. Such a response was not observed when mice were fed stored irradiated wheat. Also there was no difference between the mice fed un-irradiated wheat and stored irradiated wheat. (author)

Workshop on materials irradiation effects and applications 2012

International Nuclear Information System (INIS)

Xu, Qiu; Sato, Koichi; Yoshiie, Toshimasa

2013-01-01

For the study of the material irradiation effects, irradiation fields with improved control capabilities, advanced post irradiation experiments and well developed data analyses are required. This workshop aims to discuss new results and to plan the future irradiation research in the KUR. General meeting was held from December 14, 2012 to December 15, 2012 with 44 participants and 28 papers were presented. Especially recent experimental results using irradiation facilities in the KUR such as Materials Controlled Irradiation Facility, Low Temperature Loop and LINAC, and results of computer simulation, and fruitful discussions were performed. This volume contains the summary and selected transparencies presented in the meeting. (author)

Effects of low-level chronic irradiation on aquatic organisms

Energy Technology Data Exchange (ETDEWEB)

Etoh, H. (National Inst. of Radiological Sciences, Chiba (Japan))

1980-10-01

Effects of continual irradiation for a long term on fishes and aquatic invertebrates were outlined. Effects of low-level chronic irradiation on aquatic organisms were less than acute effects induced when the same dose was irradiated once. The radiosensitivity of the genital organ to continual irradiation was high. There was a difference in radiosensitivity of the genital organ between female and male, and the degree of the difference varied according to kinds of animals. In an experiment on continual irradiation of adult killifishes, ova recovered from radiation damage, but spermatozoa did not recover. Incubation rates of eggs obtained from aquatic organisms which lived in water where radioactive sewage flowed into decreased significantly, and the frequency of reverse position of salivary gland chromosomes which were peculiar to exposed organisms increased in larvae of Chironomus tentans.

Effect of irradiation on the streptococcus mutans

International Nuclear Information System (INIS)

Ahn, Ki Dong; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2007-01-01

To observe direct effect of irradiation on cariogenic Streptococcus mutans. S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, Transmission electron microscopy. RT-PCR, and SDS-PAGE, respectively. After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased. a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium

Effect of irradiation on the streptococcus mutans

Energy Technology Data Exchange (ETDEWEB)

Ahn, Ki Dong; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ., Seoul (Korea, Republic of)

2007-03-15

To observe direct effect of irradiation on cariogenic Streptococcus mutans. S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, Transmission electron microscopy. RT-PCR, and SDS-PAGE, respectively. After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased. a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

The effects of 500 keV electron irradiation and subsequent annealing on 1/f noise in copper films

International Nuclear Information System (INIS)

Pelz, J.; Clarke, J.

1986-01-01

Polycrystalline copper films were maintained at 90K on the cold stage of an electron microscope and irradiated with 500keV electrons to induce defects. With an electron dose of about 5 x 10 20 cm -2 , the spectral density of the noise voltage across the films increased by an order of magnitude while the electrical resistivity increased by at most 10%. The films were annealed at progressively higher temperatures; after each annealing process the 1/f noise and resistivity were remeasured at 90K. Both the 1/f noise and resistivity were reduced, but at the lower annealing temperatures the fractional reduction in the added noise was substantially more than in the added resistivity. These results suggest that a large fraction of the added noise may be generated by a small mobile fraction of the added defects that are more readily annealed than the majority of the defects. After a room temperature annealing process, both the noise and resistivity returned nearly to their initial values. The temperature dependence of the noise after irradiation and partial annealing was consistent with the Dutta-Dimon-Horn thermal activation model. (Auth.)

Effect of irradiation of sensory quality of cigarettes

International Nuclear Information System (INIS)

Feng Min; Zhu Jiating; Yang Ping; Wang Dening; Gu Guiqiang

2012-01-01

3 brands of cigarettes were irradiated and smoked to make sure the effect of irradiation on sensory qualities of cigarettes, luster, aroma, harmony, offensive taste, irritancy, after taste and total scores of irradiated cigarettes were studied. The results showed that, compared with each index of CK, some indexes changed after irradiation, sensory quality of cigarettes might be improved by suitable dose. The sensory qualities of cigarettes of different brands or different styles change differently, though they were irradiated by the same dose. There was no obvious relation between score of any index and irradiation dose, when cigarette of a same brand irradiated by different doses. Above all, the changes of sensory quality of cigarette may meet the requirements of different smokers on the palate. (authors)

Contribution to the study of the radioprotective effect of serotonin on brain spontaneous and evoked electrical activities in the adult rabbit following whole-body lethal $gamma$-irradiation

Energy Technology Data Exchange (ETDEWEB)

Fatome, M; Court, L

1973-11-01

Thesis. Submitted to Paris Univ., (France). A 1 to 12 mg/kg serotonin- creatine-sulfate intravenous injection seems to act only slightly on the chronic implanted rabbit CNS except for an increase in latencies and delays of the fast components of evoked potentials and a generalized decrease in the total energy of the signal occurring 20 to 60 min after the injection. The CNS is given a real protection by a 10 mg/kg serotonin injec, tion 20 min before a 650 R whole-body exposure, the spontaneous or induced electrical activity being slightly disturbed. In the hours following irradiation the total energy increase is less important than in the unprotected animal, and there is no clear variation towards the low frequencies. Serotonin could act on the brain structures and the total energy of the signal through its depressing effect. Its radioprotective effect could act, at least partly, through the CNS. (auth)

Effect of gamma irradiation on Korean traditional multicolored paintwork

International Nuclear Information System (INIS)

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

2015-01-01

Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe 2 O 3 ), Jangdan (Minium; Pb 3 O 4 ), Whangyun (Crocoite; PbCrO 4 ), and Jidang (Rutile; TiO 2 ), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d’Eclairage (CIE) color values (L*, a*, b*) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE* unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong. - Highlights: • Effects of gamma irradiation on the Dancheong were evaluated. • We confirmed that optical and structural properties of Dancheong were maintained. • Irradiation can contribute the

Immediate effect of irradiation on microvasculature

International Nuclear Information System (INIS)

Krishnan, L.; Krishnan, E.C.; Jewell, W.R.

1988-01-01

The immediate effects of irradiation on microvasculature in muscle in an animal model are described in this paper. By using triple isotopes of 125 I, 131 I, and 22 Na, the transcapillary transfer of albumin from the vascular bed to the extravascular space is determined in terms of mg/g of tissue, after single doses of 2 to 14 Gy. These results reveal an increase in the extravascular albumin immediately after irradiation and suggest an instantaneous compromise in vascular permeability even after 2 Gy. This effect was apparently dose related

Late radiation effects in animals surviving lethal irradiation

International Nuclear Information System (INIS)

Dimitrov, L.A.

1974-01-01

Animals (rats, mice, dogs) survived lethal irradiation by means of prophylactic-therapeutic treatments or previously irradiated, were studied for late radiation effects: life span, cachexia and fat growing of hypophysical type, tissue or organ hypoplasia manifested by disturbed hemopoiesis, suppressed function of adrenal gland, etc., suppressed immune reactivity of the irradiated organism, atypical biochemical changes in DNA and protein metabolism, epilation, chronic dermatitis, ulcerations, reduced reproductivity or full sterility, damage of kidneys leading to nephrosclerosis, dishormonal states, cataracts, diffuse sclerotic processes, various kinds of malignant and non-malignant tumors. In these cases hemopoiesis compensated for a definite time peripheral blood composition, but during the late period it showed features of incompleteness: shorter life survival of erythrocytes and thrombocytes manifested by a decreased binding of labelled methionine in these blood elements, anemia and relative thrombocytopenia sometimes with an increased number of polychromatic erythrocytes in peripheral blood and a decreased number of reticulocytes at the same time; lymphopenia and relative leucopenia with an increased number of hypersegmented neutrophils. Decreased reproductivity and atypical biochemical changes available in the first generation of the irradiated animals showed the probable role of mutagenic factors in the emergence of some late radiation effects. A significant part of late radiation sequences were due to neuro-endocrine desintegrations which lead to a disturbed supply of the vessels and afterwards to their sclerosis. Some of the described late radiation effects were also observed in biological controls as festures of ageing while in irradiated animals they were manifested in an earlier period. After application of optimal amounts radioprotectors (AET, cysteamine, serotonin) a more marked protective effect is demonstrated in the early reactions (time survival

Calculations on neutron irradiation damage in reactor materials

International Nuclear Information System (INIS)

Sone, Kazuho; Shiraishi, Kensuke

1976-01-01

Neutron irradiation damage calculations were made for Mo, Nb, V, Fe, Ni and Cr. Firstly, damage functions were calculated as a function of neutron energy with neutron cross sections of elastic and inelastic scatterings, and (n,2n) and (n,γ) reactions filed in ENDF/B-III. Secondly, displacement damage expressed in displacements per atom (DPA) was estimated for neutron environments such as fission spectrum, thermal neutron reactor (JMTR), fast breeder reactor (MONJU) and two fusion reactors (The Conceptual Design of Fusion Reactor in JAERI and ORNL-Benchmark). then, damage cross section in units of dpa. barn was defined as a factor to convert a given neutron fluence to the DPA value, and was calculated for the materials in the above neutron environments. Finally, production rates of helium and hydrogen atoms were calculated with (n,α) and (n,p) cross sections in ENDF/B-III for the materials irradiated in the above reactors. (auth.)

Effects of irradiation on ceramics for fusion-reactor applications

International Nuclear Information System (INIS)

Porter, D.L.

1982-12-01

The purpose of this study, coordinated with efforts of LANL and Grumman Aircraft, was to lay some basic groundwork to study the irradiation effects on the engineering properties of some useful classes of ceramic materials; ANL's efforts were pointed towards multiphase materials (glass ceramics and partially-stabilized zirconias). The materials were irradiated at 400 and 550 0 C to fast (E > 0.1 MeV) neutron fluences of approx. 2 x 10 22 n/cm 2 . Fluorophlogapite mica based glass ceramics (Macor, etc.) were found susceptible to weakening due to void formtion between mica plates. Composition variations within this class of glass ceramics seemed to cause sharp variations in the magnitude of the effect. Lithium silicate glass ceramic (ReX) showed sharp contrasts between the effects of ionization irradiation and displacement damage, neutron irradiation having little effect on the ReX structure while electron irradiation creating lithium silicate vitrification and rapid structural annealing

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish.

Science.gov (United States)

Smith, Richard W; Seymour, Colin B; Moccia, Richard D; Mothersill, Carmel E

2016-02-01

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. Copyright © 2015 Elsevier Inc. All rights reserved.

Radioprotective effect of RSP-CM on mice irradiated with different doses

International Nuclear Information System (INIS)

Zhang Xia; Yang Rujun; Zhang Xin; Yang Yunfang; Jin Zhijun; Xiang Yingsong

2000-01-01

Objective: To investigate the radioprotective effects of cytokines on hematopoietic impairment of irradiated mice. Methods: Using RSP-CM and LP3-CM respectively originated GM-CSF and G-CSF to treat ICR mice irradiated with different doses of 60 Co γ-rays. The 30-day survival rate of mice, the mean survival days of dead mice were determined and the numbers of peripheral white blood cells and BMC of part of the mice were counted. At the same time, GM clonogenic activity of BM was assayed. Results:RSP-CM could effectively raise 30-day survival rate of mice irradiated with 7.5 Gy. However, LP3-CM had no obvious effect. Judging from the comparative survival ratio, only the RSP-CM treated group showed protective effect on the 8.0 Gy -irradiated mice. The 8.5 Gy-irradiated mice all died within 30 days, indicating that GM-CSF had weak effect on higher dose-irradiated mice. Conclusion: GM-CSF can stimulate the hematopoietic system of irradiated mice, and has dose-effect and time-effect relations. M-CSF used singly has no obvious effect

Radiation effects on vasoproliferation

International Nuclear Information System (INIS)

Yamaura, Hirotsugu; Matsuzawa, Taiju

1975-01-01

The authors quantitatively examined radiation effects on vascular proliferarion, using the rat transparent chamber technique to observe the living microcirculation. We studied the process of vasoproliferation and revascularization from the surrounding pre-existing vessels into the surgically avascularized area in the chamber, by measuring the vascular lenght photographically. A hyper-vascularized zone, about 0.5 mm in with, was formed on the vascularizing frontier, the significance of which is so far not known. When the chambers were irradiated with various doses of 60 Co γ-rays, a dose dependent inhibition of vasoproliferation was observed. (auth.)

Effect of helium irradiation on fracture modes

International Nuclear Information System (INIS)

Hanamura, T.; Jesser, W.A.

1982-01-01

The objective of this work is to determine the crack opening mode during in-situ HVEM tensile testing and how it is influenced by test temperature and helium irradiation. Most cracks were mixed mode I and II. However, between 250 0 C and room temperature the effect of helium irradiation is to increase the amount of mode I crack propagation. Mode II crack opening was observed as grain boundary sliding initiated by a predominantly mode I crack steeply intersecting the grain boundary. Mode II crack opening was absent in irradiated specimens tested between 250 0 C and room temperature, but could be restored by a post irradiation anneal

Low-energy irradiation effects of gas cluster ion beams

International Nuclear Information System (INIS)

Houzumi, Shingo; Takeshima, Keigo; Mochiji, Kozo; Toyoda, Noriaki; Yamada, Isao

2007-01-01

A cluster-ion irradiation system with cluster-size selection has been developed to study the effects of the cluster size for surface processes using cluster ions. A permanent magnet with a magnetic field of 1.2 T is installed for size separation of large cluster ions. Trace formations at HOPG surface by the irradiation with size-selected Ar-cluster ions under acceleration energy of 30 keV were investigated by a scanning tunneling microscopy. Generation behavior of the crater-like traces is strongly affected by the number of constituent atoms (cluster size) of the irradiating cluster ion. When the incident cluster ion is composed of 100-3000 atoms, crater-like traces are observed on the irradiated surfaces. In contrast, such traces are not observed at all with the irradiation of the cluster-ions composed of over 5000 atoms. Such the behavior is discussed on the basis of the kinetic energy per constituent atom of the cluster ion. To study GCIB irradiation effects against macromolecule, GCIB was irradiated on DNA molecules absorbed on graphite surface. By the GCIB irradiation, much more DNA molecules was sputtered away as compared with the monomer-ion irradiation. (author)

Paint compositions for indicating irradiation dose

International Nuclear Information System (INIS)

Maruyama, T.; Murata, K.

1975-01-01

Paint compositions for indicating irradiation dose are prepared from chlorine-combined polyester, 5 to 30 percent by weight of a reductive discoloring substance or a mixture of said substances, and/or 0.005 to 2.0 percent by weight of a reducing dyestuff or a mixture of said dyestuffs, in which said chlorine-combined polyester is obtained by a chlorinated dibasic acid or its anhydride as an acid component or a part of an acid component selected from a group consisting of 3-chlorophthalic acid, 4-chlorophthalic acid, dichlorinated phthalic acid, tetrachlorophthalic acid, 1,4,5,6,7,7-hexachlorobicyclo-(2,2,1)-5-heptene-2,3-dicarboxylic acid, 4-chloro-4-cyclohexene-1,2-dicarboxylic acid and the anhydrides corresponding to said acids. (auth)

Irradiation effects in superconductor oxides. Effets d'irradiation dans les oxydes supraconducteurs

Energy Technology Data Exchange (ETDEWEB)

Rullier-Albenque, F; Konczykowski, M [CEA-Ecole Polytechnique, 91 - Palaiseau (France). Lab. d' Etudes des Solides Irradies

1993-01-01

Several effects of irradiation on the 92 K - oxide superconductor YBa[sub 2]Cu[sub 3]O[sub 7] are reported. Whatever irradiation type, the critical temperature T[sub c] is found to decrease and the resistivity to increase. At sufficiently high damage levels, YBa[sub 2]Cu[sub 3]O[sub 7] is no longer superconducting and even displays a semiconducting-like behaviour. The alterations of superconducting properties are clearly related to oxygen defects - in the CuO[sub 2] planes or CuO chains... but we have shown experimentally that copper defects are also important. Magnetic properties of YBa[sub 2]Cu[sub 3]O[sub 7] in mixed state are also very sensitive to irradiation. By pinning the flux lines, irradiation defects can considerably increase the critical current density j[sub c]. At present, irradiations by highly energetic heavy ions (6 GeV Pb for instance), which produce cylindrical tubes of amorphous material (latent tracks) throughout the whole thickness of the samples, are probably the most efficient way to enhance j[sub c]. (Author). 18 refs., 7 figs.

Similarity between the effects of carbon-ion irradiation and X-irradiation on the development of rat brain

International Nuclear Information System (INIS)

Inouye, Minoru; Hayasaka, Shizu; Murata, Yoshiharu; Takahashi, Sentaro; Kubota, Yoshihisa

2000-01-01

The effects of carbon-ion irradiation and X-irradiation on the development of rat brain were compared. Twenty pregnant rats were injected with bromodeoxyuridine (BrdU) at 9 pm on day 18 pregnancy and divided into five groups. Three hours after injection (day 19.0) one group was exposed to 290 MeV/u carbon-ion radiation by a single dose of 1.5 Gy. Other groups were exposed to X-radiation by 1.5, 2.0 or 2.5 Gy, or sham-treated, respectively. Fetuses were removed from one dam in each group 8 h after exposure and examined histologically. Extensive cell death was observed in the brain mantle from the irradiated groups. The cell death after 1.5 Gy carbon-ion irradiation was remarkably more extensive than that after 1.5 Gy X-irradiation, but comparable to that after 2.0 Gy or 2.5 Gy X-irradiation. The remaining rats were allowed to give birth and the offspring were sacrificed at 6 weeks of age. All of the irradiated offspring manifested microcephaly. The size of the brain mantle exposed to 1.5 Gy carbon-ion radiation was significantly smaller than that exposed to 1.5 Gy X-radiation and larger than that exposed to 2.5 Gy X-radiation. A histological examination of the cerebral cortex revealed that cortical layers II-IV were malformed. The defect by 1.5 Gy carbon-ion irradiation was more severe than that by the same dose of X-irradiation. Although the BrdU-incorporated neurons were greatly reduced in number in all irradiated groups, these cells reached the superficial area of the cortex. These findings indicated that the effects of both carbon-ion irradiation and X-irradiation on the development of rat brain are similar in character, and the effect of 1.5 Gy carbon-ion irradiation compares to that of 2.0-2.5 Gy X-irradiation. (author)

Combined effect of external and internal irradiation

International Nuclear Information System (INIS)

Kiradzhiev, G.

1987-01-01

Some of the general regularities of the combined effect of external irradiation and iodine 131 are discussed. Data are adduced showing that modification of the effects of these two radiation factors, when jointly applied, is also determined by the quantitative relations of the applied doses of external and internal irradiation, referred to a particular moment of the effects. It was shown that the effects of the radionuclides in these combined radiation injuries are basically realized by two mechanisms: 1. changes are found in the radionuclide kinetic parameters (nonspecific effects); 2. changes in their kinetic parameters are absent (specific effect). These two mechanisms underlie different approaches to therapy

Neutron irradiation damage in Al2O3 and Y2O3

International Nuclear Information System (INIS)

Clinard, F.W. Jr.; Bunch, J.M.; Ranken, W.A.

1975-01-01

Two ceramics under consideration for use in fusion reactors, Al 2 O 3 and Y 2 O 3 , were irradiated in the EBR-II fission reactor at 650, 875, and 1025 0 K to fluences between 2 and 6 x 10 21 n/cm 2 (E greater than 0.1 MeV). Samples evaluated include sapphire, Lucalox, alumina, Y 2 O 3 , and Y 2 O 3 -10 percent ZrO 2 (Yttralox). All Al 2 O 3 specimens swelled significantly (1 to 3 percent), with most of the growth observed in sapphire along the c-axis at the higher temperatures. Al 2 O 3 samples irradiated at 875 to 1025 0 K contained a high density of small aligned ''pores''. Irradiated Y 2 O 3 -based ceramics exhibited dimensional stability and a defect content consisting primarily of unresolved damage and/or dislocation loops. The behavior of these ceramics under irradiation is discussed, and the relevance of fission neutron damage studies to fusion reactor applications is considered. (auth)

Research on sprout inhibition effect of refrigerated garlic by irradiation

International Nuclear Information System (INIS)

Zhang Xuan; He Jianzhong; Li Ruijun

2005-01-01

This paper researches the sprout inhibition effect by irradiation on refrigerated garlic. The results shows that, the garlic is still in the period of dormancy within 7 days after taken out from the refrigerated warehouse, and irradiation have a good sprout inhibition effect on it. The irradiation dose is 40-90 Gy, the same as that of the post harvest irradiation treatment on garlic. Refrigerate the Zhongmu Garlic (at -2 degree C-0 degree C) until the middle ten days of February the next year, place it at the room temperature (10 degree C-15 degree C) for 1-7 days after taking it out of the warehouse, then use 60 Co γ-ray to irradiate it until the absorbed dose reaches 40-90 Gy, the sprout inhibition effect can be realized. The test also indicates that the deposited time after taking out of the refrigerated warehouse is crucial to the sprout inhibition effect of refrigerated garlic by irradiation. (authors)

Dose-response relations for dicentric yields in G0 lymphocytes of man and crab-eating monkey following acute and chronic γ-irradiations

International Nuclear Information System (INIS)

Takahashi, E.; Hirai, M.; Tobari, I.; Nakai, S.A.

1979-01-01

A comparison has been made of dicentric yields in G 0 lymphocytes between man and crab-eating monkey, Macaca fascicularis, after acute and chronic γ-irradiations. With acute irradiation (49.6 rad/min) there was no significant difference between them, but for the chronic irradiation (17.1 rad/h) a significant difference was observed between the species. When the dose-response relations were fitted to the linear-quadratic model (Y = αD + βD 2 ), the species-difference observed for chronic irradiation was almost entirely due to change in the value of β. In addition, after chronic irradiation the β-value for monkey was almost negligible, but that for man was significant. Post-irradiation incubation experiment showed that cells with dicentrics were partly eliminated during the course of chronic irradiation, because there were appreciable reductions of dicentric yields (ca. 25% for both man and monkey at 400 rad) together with mitotic indices (ca. 30% and 60% for man and monkey, respectively, at 400 rad). Accordingly, it would be reasonable to postulate that G 0 repair for dicentrics other than selection mechanism must play a major role in the effects of low dose rate. It can be further suggested that G 0 -repair capacity for chromosal damages leading to dicentrics may be different among different primate species. (Auth.)

Preparation by irradiation of a solid support for enzyme immunoassay

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.

1984-01-01

Reagents (immobilized anti-α-fetoprotein discs) having a porous structure were prepared for enzyme immunoassay of α-fetoprotein by radiation polymerization at low temperatures. Discs were attached to sticks for easy handling. The activity (determined by absorbance at 492 nm) of the discs varied with the hydrophilic properties and size of the discs. The discs are sufficiently sensitive and precise for enzyme immunoassay of α-fetoprotein. Anti-AFP dissolved in PBS solution was mixed with a monomer solution of hydroxyethyl methacrylate and hydroxypropyl methacrylate. The mixture was frozen to -78 0 C and gamma irradiated. (Auth.)

Effects of cryogenic reactor irradiation on organic insulators

International Nuclear Information System (INIS)

Kato, Teruo

1995-01-01

Insulators for the superconducting magnets of fusion reactor are classified as electrical and thermal insulators for which tough organic materials will be used. When the magnet is exposed by fast neutrons and gamma-rays from plasma in a fusion reactor, the fusion reactor systems will cause fatal damage by the degradation of insulators. Therefore, it is necessary to select materials resistant irradiation damage for use as insulators. Electrical and mechanical tests were carried out at 4.2 K without warmup after the reactor irradiation at 5 K. The effects of reactor irradiation at the dose of 10 7 Gy on epoxy resins (bisphenol-A), G-10 CR, VL-E 200 and G-11 CR caused large decreases in mechanical strength. Polyetheretherketone (PEEK), polyimide and phenol novolac resins, which were used to laminate reinforced plastics with glass-cloth against irradiation, showed good resistance. Effects of cryogenic reactor irradiation on several organic materials and epoxy laminate-reinforced plastics with glass-cloth and Kevlar-cloth were also discussed. (author)

Electron irradiation effect on single crystal of niobium

International Nuclear Information System (INIS)

Otero, M.P.; Lucki, G.

1984-01-01

The effect of electron irradiation (900 KeV) on gliding dislocations of single crystal Nb with its tensile axe in the [941] orientation was observed for the in-situ deformation in a high voltage electron microscope (HVEM) at Argonne National Laboratory. The experimental was carried out by the 1 hour-electron irradiation with no stress applied. Straight dislocations actuating as sinks for the electron produced defects became helicoidal as the irradiation proceeded. Frenkel pairs were created in Nb for electron energies > = 650 KeV and, as the single vacancies do not undergo long-range migration in Nb at temperatures much below 620 K, the defects that are entrapped by the dislocations are self-interstitials produced by electron displacement. Applying the stress it was possible to observe that modified dislocations did not glide while the dislocations not affected by the irradiation are visibly in movement. This important result explains the neutron and electron-irradiation induced work-hardening effect for Nb that was previously observed. (Author) [pt

Effects of irradiation on mechanical properties

International Nuclear Information System (INIS)

Server, W.L.; Griesbach, T.J.; Dragunov, Y.; Amaev, A.

1998-01-01

As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In this report, background and contemporary views on specially identified areas of the subject are considered as self-contained chapters, written by experts. The effects of irradiation on the mechanical properties of reactor pressure vessel steels are explained. This chapter provides some background on the critical elements controlling neutron damage effects. Distinction is made between vessels made in the USA and in the former USSR

Effect of endotoxin preparations (LPS) with irradiation decreased toxicity on the immune response of normal and irradiated rats

Energy Technology Data Exchange (ETDEWEB)

Elekes, E; Bertok, L [Orszagos Frederic Joliot-Curie Sugarbiologiai es Sugaregeszsegugyi Kutato Intezet, Budapest (Hungary)

1979-03-01

A comparison of the immunostimulating effect of parent and radiodetoxified with 50, 100, 150 and 200 kGy (5, 10, 15 and 20 Mrad) /sup 60/Co ..gamma..-rays endotoxin preparations in normal and irradiated rats is given. By increasing the dose of irradiation the immunostimulating effect decreased. The preparations detoxified even with the highest (200 kGy) dose is characterized by a pronounced adjuvant effect in irradiated animals.

Effects of irradiation on minerals and their consequences in geo-chronology

International Nuclear Information System (INIS)

Seydoux-Guillaume, Anne-Magali

2011-01-01

In this HDR (accreditation to supervise research studies) report, the author first gives a brief overview of her scientific approach. Then, addressing the irradiation of minerals by a radioactive source, she discusses the effects of irradiation, notably in the case of monazite, reports an experimental approach of external irradiation by ion beams, and comments some side effects like irradiation of host minerals. She also comments how irradiation-induced damages interfere with some processes like diffusion kinetics and dissolution. She addresses the case of mineral irradiation by means of a femto-second laser source: scientific approach, effects on mineral microstructure, notably in the case of monazite and quartz. The last part discusses issues in abeyance and perspectives in the field of irradiation textures, consequences on the geo-chronological response, alteration mechanisms, role of defects, and contribution of experimental irradiation

Modification of the genetic effect of gamma irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1985-01-01

The authors study the effect of direct current of varying strength and polarity on the genetic damage due to gamma irradiation of Vicia faba seedlings. The modificational effect of direct current observed earlier is confirmed here. The extent and nature of this effect depends on the strength and polarity of the current as well as interval between irradiation and exposure to the electric field. Conditions having no effect on the irradiated seedlings, those protecting the cells from damage and enhancing the irradiation effect, are identified

Tradescantia in studies of genetic effects of low level radiation

International Nuclear Information System (INIS)

Yamashita, Atsushi

1976-01-01

Tradescantia in studies on genetic effects of low level radiation is briefly introduced. Radiosensitivity, method of screening stamen hair mutation, materials in current uses, spontaneous mutation rate, and modifying factors are refered. For stamen hair mutation b values in exponential model were lower in irradiation with low dose rate at high environmental temperature. The dose response curves under these modifying conditions, when extrapolated to low dose range, well fit to the line which was obtained by Sparrow's experiment of low level irradiation. In chronic irradiation, the frequency of stamen hair mutation reaches to the constant value after 17 days from the start of irradiation, and is as much as 4 times higher than the peak value in one day irradiation at the same exposure rate. The spontaneous mutation rate of KU-7 varied with temperature. The increase with 1 0 C increment of mean temperature was -0.04%. Uses of Tradescantia in monitoring the environmental radiation is discussed. (auth.)

Selective inhibition of precursor incorporation into ribosomal RNA in gamma-irradiated Tetrahymena pyriformis

International Nuclear Information System (INIS)

Ernst, S.G.; Oleinick, N.L.; Rustad, R.C.; Greenblatt, R.M.

1979-01-01

Sublethal doses of γ radiation are known to inhibit total RNA synthesis in the ciliate protozoan Tetrahymena. To determine if the synthesis of a particular class of RNA is preferentially inhibited, pulse-labeled RNA was isolated from normal exponentially growing cells, irradiated cells, and cells in which total RNA synthesis had recovered to the pre-irradiation level. The RNAs were analyzed by SDS-polyacrylamide gel electrphoresis and oligo(dT)-cellulose column chromatography. Inhibition of RNA synthesis primarily involves ribosomal RNA. However, radiation does not cause a delay in the processing of precursor rRNA or a preferential loss of either of the mature rRNAs. Following irradiation, poly(A)-containing RNA [poly(A+)RNA] is synthesized at a rate up to three times greater than the control rate. The elevated poly(A+)RNA synthesis occurs during the period of depressed rRNA synthesis and even after rRNA synthesis has recovered to its pre-irradiation rate. While the sizes of the total cellular ribonucleoside triphosphate pools are depressed in the irradiated cells, these pools probably do not represent the actual compartments containing the precursors for RNA synthesis, and the observed changes cannot explain the modifications in macromolecular synthesis in irradiated Tetrahymena. (Auth.)

Thymic nurse cells and thymic repopulation after whole body sublethal irradiation in mice

International Nuclear Information System (INIS)

Houben-Defresne, M.P.; Varlet, A.; Boniver, J.

1984-01-01

Thymic Nurse Cells (TNCs) are lymphoepithelial complexes which are thought to play a role in the early stages of the intrathymic differentiation pathway. Their repopulation kinetics were analyzed in mice after sublethal whole-body irradiation. Changes of the number of TNCs per thymus were parallel with the evolution of the whole thymocyte population. Particularly, a first wave of TNCs restoration was followed by a secondary depletion and a final recovery. This suggests that TNCs restoration is related to the proliferating progeny of intrathymic radioresistant thymocytes. When normal bone marrow cells were grafted intravenously after irradiation, no secondary depletion was found. This pattern of restoration was obviously related to thymic repopulation by cells which were derived from the inoculated bone marrow. Homing studies with FITC labelled bone marrow cells showed that inoculated bone marrow cells did not penetrate TNCs early after irradiation. Later on, when immigrant cells started to proliferate, they were found preferentially within TNCs before spreading in the whole thymus. (Auth.)

The biological effectiveness of antiproton irradiation

DEFF Research Database (Denmark)

Holzscheiter, Michael H.; Bassler, Niels; Agazaryan, Nzhde

2006-01-01

ever measurements of the biological effectiveness of antiprotons. Materials and methods: V79 cells were suspended in a semi-solid matrix and irradiated with 46.7 MeV antiprotons, 48 MeV protons, or 60Co c-rays. Clonogenic survival was determined as a function of depth along the particle beams. Dose...... and particle fluence response relationships were constructed from data in the plateau and Bragg peak regions of the beams and used to assess the biological effectiveness. Results: Due to uncertainties in antiproton dosimetry we defined a new term, called the biologically effective dose ratio (BEDR), which...... has a higher relative biological effectiveness (RBE). Conclusion: We have produced the first measurements of the biological consequences of antiproton irradiation. These data substantiate theoretical predictions of the biological effects of antiproton annihilation within the Bragg peak, and suggest...

Effect of gamma irradiation on Korean traditional multicolored paintwork

Science.gov (United States)

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

2015-10-01

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

Effect of irradiation on analgesia induced by morphine and endorphin

International Nuclear Information System (INIS)

Kim, Jin Kyu; Lee, Byoung Hun; Hyun, Soung Hee; Chung, Ki Myung

2003-01-01

Morphine and endorphin administered intracerebroventricularly (i.c.v.) produce analgesia by activating different descending pain inhibitory systems. Gamma irradiation attenuates the acute analgesic action of i.c.v. injected morphine in mice. This study was done to investigate the effect of-irradiation on the analgesia produced by i.c.v. injected morphine and endorphin in male ICR mice. In one group, mice were exposed to whole-body irradiation at a dose of 5 Gy from a 60 Co source and the analgesic effects were tested 5, 30, 60, 90 and 180 min after irradiation using the acetic acid-induced writhing test. The analgesic effect was produced time-dependently and reached its maximum at 90 min after irradiation. Thus, time was fixed in the following studies. In another group, mice were irradiated with 5 Gy and tested 90 minutes later for analgesia produced by i.c.v. administration of morphine or endorphin. Irradiation significantly potentiated the analgesia produced by endorphin. However, the antinociception produced by morphine was not affected by irradiation. These results support the hypothesis that morphine and endorphin administered supraspinally produce antinocieception by different neuronal mechanisms

Effect of irradiation on analgesia induced by morphine and endorphin

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Kyu; Lee, Byoung Hun; Hyun, Soung Hee; Chung, Ki Myung [KAERI, Daejeon (Korea, Republic of)

2003-07-01

Morphine and endorphin administered intracerebroventricularly (i.c.v.) produce analgesia by activating different descending pain inhibitory systems. Gamma irradiation attenuates the acute analgesic action of i.c.v. injected morphine in mice. This study was done to investigate the effect of-irradiation on the analgesia produced by i.c.v. injected morphine and endorphin in male ICR mice. In one group, mice were exposed to whole-body irradiation at a dose of 5 Gy from a {sup 60}Co source and the analgesic effects were tested 5, 30, 60, 90 and 180 min after irradiation using the acetic acid-induced writhing test. The analgesic effect was produced time-dependently and reached its maximum at 90 min after irradiation. Thus, time was fixed in the following studies. In another group, mice were irradiated with 5 Gy and tested 90 minutes later for analgesia produced by i.c.v. administration of morphine or endorphin. Irradiation significantly potentiated the analgesia produced by endorphin. However, the antinociception produced by morphine was not affected by irradiation. These results support the hypothesis that morphine and endorphin administered supraspinally produce antinocieception by different neuronal mechanisms.

Induced effect of irradiated exogenous DNA on wheat

International Nuclear Information System (INIS)

Li Zhongjie; Sun Guangzu; Wang Guangjin

1996-01-01

Irradiated exogenous DNA introduced into wheat can give rise to break of DNA-chain and damage of part of alkali radicals. Introducing exogenous DNA irradiated by γ rays could increase Do fructification rate and decrease seed size and plumpness. These tendencies became obvious with dose increase. In comparison with control DNA, introducing DNA irradiated could raise evidently mutagenic effect of pollen tube pathway technique

S1-sensitive sites in DNA after γ-irradiation

International Nuclear Information System (INIS)

Martin-Bertram, H.

1981-01-01

DNA from γ-irradiated T 1 bacteriophages was analyzed for 'single-stranded' sites by cleavage with S1 nuclease from Aspergillus oryzae as lesion probe. The ratio of 'S1-sensitive sites' to the amount of radiation-induced single-strand breaks was about one. Presumably these 'denatured' sites were associated with single-strand breaks. The subsequent check for the persistence of 'single-stranded' sites within the DNA molecule by thermokinetics demonstrated a strong affinity of the nuclease to its substrate, the single-stranded lesion, and a perfect excision. It is assumed that the direct absorption of radiation energy in the DNA gives rise to the formation of such bulky lesions. (Auth.)

Effect of electron beam irradiation on fisheries water

International Nuclear Information System (INIS)

Sarala Selambakkannu; Khomsaton Abu Bakar; Jamaliah Shariff; Suhairi Alimon

2012-01-01

This paper studies about water obtained from fish pond of fisheries research centre. Usual water quality parameters such as pH, COD, Turbidity and Ammonia content were analyzed before and after irradiation. Electron beam irradiation was used to irradiate the water with the dose 100 kGy, 200 kGy and 300 kGy. Only high dose was applied on this water as only a limited amount of samples was supplied. All the parameters indicated a slight increase after irradiation except for the ammonia content, which showed a gradual decrease as irradiation dose increases. Sample condition was changed before irradiation in order to obtain more effective results in the following batch. The water sample from fisheries was diluted with distilled water to the ratio of 1:1.This was followed with irradiation at 100 kGy, 200 kGy and 300 kGy. The results still showed an increase in all parameters after irradiation except for ammonia content. For the following irradiation batch, the pH of the sample was adjusted to pH 4 and pH 8 before irradiation. For this sample the irradiation dose selected was only 100 kGy. A higher value of ammonia was observed for the sample with pH 4 after irradiation. Other parameters were almost the same as the first two batches. (author)

The electron irradiation effects in different structures of diodes

International Nuclear Information System (INIS)

Li Quanfen; Wang Jiaxu

1993-01-01

This paper describes the different electron irradiation effects in different structures of diodes and the different results produced by different irradiation ways. From this work, we can know how to choose proper manufacture arts and comprehensive factors according to the structures of diodes and the irradiation conditions

Effects of irradiation on the components of implantable pacemakers

CERN Document Server

Kawamura, S; Kuga, N; Shiba, T; Hirose, T; Fujimoto, H; Toyoshima, T; Hyodo, K; Matoba, M

2003-01-01

The purpose of this study was to examine the effects of irradiation on implantable pacemaker components. The pacemaker was divided into three components: lead wire and electrode, battery, and electrical circuit, and each component was irradiated by X-ray and electron beams, respectively. The pacemaker parameters were measured by both telemetry data of the programmer and directly measured data from the output terminal. The following results were obtained. For the lead wire and electrode, there was no effect on the pacemaker function due to irradiation by X-ray and electron beams. In the case of battery irradiation, there was no change in battery voltage or current up to 236 Gy X-ray dose. In the electrical circuit, the pacemaker reverted to the regular beating rate (fixed-rate mode) immediately after the start of X-ray irradiation, and it continued in this mode during irradiation. In patients with their own heartbeat rhythm, changing to the fixed-rate mode may cause dangerous conditions such as ventricular fib...

Effects of irradiation of sewage sludge on heavy metal bioavailability

International Nuclear Information System (INIS)

Sheppard, S.C.; Mayoh, K.R.

1986-10-01

Sewage sludges are a valuable resource to agriculture, but their use is limited by the hazards of pathogens, toxic chemicals and heavy metals. Irradiation can control the pathogens and deactivate some of the toxic chemicals. The relative cost of industrial-scale irradiation using accelerators has decreased progressively. This, coupled with the increasing necessity to recycle wastes, has led to renewed interest in irradiation of sludges. In response to this renewed interest, this report examines what is known about the effects of irradiation on the bioavailability of heavy metals. Very few studies have addressed this topic, although workers in the U.S. have claimed decreased solubility of metals in irradiated sludges. We have also briefly reviewed the general literature on sludge to gain indirect evidence on the likely effects. The scant data, often based on less than ideal experimental methodologies, show no major consistent effects of irradiation on the availability of heavy metals from sludge. The data are not sufficient to rule out such effects entirely, but the effects appear to be fairly subtle and not likely to persist beyond one growth season. 85 refs

The effect of irradiation atmosphere on NMR absorption of 60Co γ-rays irradiated polytetrafluoroethylene

International Nuclear Information System (INIS)

Tutiya, Mituaki

1975-01-01

The radiation stability of polytetrafluoroethylene (PTFE) is sensitive to the presence of oxygen during irradiation. In semicrystalline polymers such as PTFE, it is expected that the influence of irradiation differs in crystalline and amorphous regions, therefore the magnitude of irradiation effect in amorphous region was compared with that in crystalline region of PTFE. In the NMR measurement by the author, the main difference between the PTFE samples annealed after irradiation in air and in vacuum was that the increase in crystallinity and the lowering of crystalline transition temperature Tsub(t) were accelerated in the former case. The scission probability of C-C bonds r can be estimated from the radiation-induced increase in crystallinity in the amorphous region of PTFE, and the value of r in the crystalline region can also be calculated. According to previous papers, the ratio of the scission probability in air to that in vacuum was estimated to be about 7 in the amorphous region and 1.8 in the crystalline region of PTFE. From this fact, the following conclusions were drawn. Main chain scission was accelerated when PTFE was irradiated in air. In PTFE, the amorphous region was affected more by irradiation atmosphere than the crystalline region. In both air and vacuum irradiation, the scission probability in the amorphous region was larger than that in the crystalline region. The effect of irradiation on PTFE was affected by oxygen diffusion, the life time of free radicals, and the degree of packing of molecular chains. (Kako, I.)

Ion irradiation-induced swelling and hardening effect of Hastelloy N alloy

Energy Technology Data Exchange (ETDEWEB)

Zhang, S.J. [Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li, D.H.; Chen, H.C.; Lei, G.H.; Huang, H.F.; Zhang, W.; Wang, C.B. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Yan, L., E-mail: yanlong@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Fu, D.J. [Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Tang, M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2017-06-15

The volumetric swelling and hardening effect of irradiated Hastelloy N alloy were investigated in this paper. 7 MeV and 1 MeV Xe ions irradiations were performed at room temperature (RT) with irradiation dose ranging from 0.5 to 27 dpa. The volumetric swelling increases with increasing irradiation dose, and reaches up to 3.2% at 27 dpa. And the irradiation induced lattice expansion is also observed. The irradiation induced hardening initiates at low ion dose (≤1dpa) then saturates with higher ion dose. The irradiation induced volumetric swelling may be ascribed to excess atomic volume of defects. The irradiation induced hardening may be explained by the pinning effect where the defects can act as obstacles for the free movement of dislocation lines. And the evolution of the defects' size and number density could be responsible for the saturation of hardness. - Highlights: •Irradiation Swelling: The irradiation induced volumetric swelling increases with ion dose. •Irradiation Hardening: The irradiation hardening initiates below 1 dpa, then saturates with higher ion dose (1–10 dpa). •Irradiation Mechanism: The irradiation phenomena are ascribed to the microstructural evolution of the irradiation defects.

Effect of γ-ray irradiation on the properties of concrete

International Nuclear Information System (INIS)

Muraoka, Susumu; Murase, Yoshinobu; Yamada, Kiyotsugu

1983-02-01

In order to obtain the fundamental data of concretes which are used in the construction of storange facilities of HLW, the effect of γ-ray irradiation on the properties of concretes was evaluated. After curing in water for about 4 weeks, concretes were stored under three different condition; 1) heating with γ-ray irradiation, 2) heating without γ-ray irradiation, and 3) controlled at 20 0 C, Relative Humidty of 90%; for 300, 600, and 1200 hours. Then, concretes were tested about the changes of weight, compressive strength, modulus of elasticity, Poisson's ratio, dimension and carbonation depth. Heating temperature were 100, 160 and 190 0 C. Consequently, it was concluded that the effect of γ-ray irradiation within the range of 1.0 x 10 9 R on the properties of concrete was uncertain, and that the effect of heating was more distinguished than γ-ray irradiation effect. (author)

The work of the 'Irradiation Damage' sub-group of the EURATOM Working Group on Research Reactor Dosimetry

International Nuclear Information System (INIS)

Genthon, J.P.

1975-01-01

The EURATOM Working Group on Reactor Dosimetry is investigating the problems of the dosimetry of radiation damage experiments. Papers have been published on the dosimetry of graphite and irradiation of metals: the model chosen, the quantities employed to express the fluences, numerical values, measurements, and measurement techniques. The ensuing work of the EURATOM Working Group of Reactor Dosimetry in these areas will deal with the measurement methods required for the dosimetry of radiation damage. (Auth.)

Growth hormone and somatomedin effects on calcification following X-irradiation, glucocorticoid treatment or fasting

International Nuclear Information System (INIS)

Dearden, L.C.; Mosier, H.D. Jr.

1986-01-01

Growth hormone (GH) is thought to activate the liver to produce a peptide called somatomedin (SM) and this substance putatively stimulates linear growth in long bones by its action on cartilagenous epiphyseal plates. These actions include stimulating chondrocytes to synthesize the carbohydrate and protein components of proteoglycan and of collagen, enhancing the synthesis of ribo and desoxyribonucleic acids, and possibly to increase cell division. In GH deficiencies there is a narrowing of the epiphyseal growth plate and cartilage calcification is enhanced concurrent with proteoglycan and collagen alterations in the extracellular matrix. Calcium and phosphate ions accumulate in mitochondria followed by their release as the calcification zone is approached, and matrix vesicles, which possess the chemical machinery necessary to induce the format0344of apatite crystals within them, increase. Therefore, if GH and/or SM levels are altered, there should be corresponding alterations in growth or in cartilage calcification. In the present study we have investigated rats after head X-irradiation, fasting, and corticosteroid treatment, and all of these treatments reduce GH and SM. (Auth.)

Meiosis in untreated and irradiated cyperus eragrostis vahl

International Nuclear Information System (INIS)

Bokhari, F.S.

1976-01-01

A cytological investigation of meiosis is seed irradiated Cyperus eragrostis has shown that the diffuse centromeric type of chromosome organisation leads to the formation of inviable chromosome complements, in which complex configurations resulting from stickiness as well as pairing of homologous regions, and numerous fragments, persist to the formation of pollen grains. At the higher doses, however, there is complete sterility, and low fertility even at the lower doses. The small numbers of M 2 and M 3 plants produced at lower doses show much reduced chromosomal abnormalities, indicating severe selection among the gametes and zygotes formed. There is little advantage in terms of survival from radiation damage, resulting from the possession of the diffuse centromere. (auth.)

Combined radiosensitizer infusion and irradiation of osteogenic sarcomas

International Nuclear Information System (INIS)

Goffinet, D.R.; Kaplan, H.S.; Donaldson, S.S.; Bagshaw, M.A.; Wilbur, J.R.

1975-01-01

Three children with osteogenic sarcomas which were either unresectable or whose parents refused permission to amputate were treated with combined intra-arterial 5'bromodeoxyuridine (BUdR) infusion and high-dose-per-fraction megavoltage irradiation to the primary site. Pulsed, 48-hour BUdR infusions were performed prior to each 600-rad radiation therapy fraction, with a total radiation dose to the primary site of 4,200 to 4,800 rads in five weeks. Local control was obtained in all 3 children. One child is alive two years after treatment, another died with metastatic disease, and the third patient who received radiotherapy to the lungs for pulmonary metastases is without evidence of disease one year later. (auth)

Effect of electron beam irradiation on seed germination

Energy Technology Data Exchange (ETDEWEB)

Han, Seunghee; Bae, Youngmin [Changwon Univ., Changwon (Korea, Republic of)

2013-07-01

Effect of electron beam irradiation on seed germination was investigated in this research. Electron beam of 0.5, 1.0, 1.5 and 2.0 kGy was irradiated to the seeds of lettuce, green onion and cucumber, and the irradiated seeds were incubated at 25 .deg. Cn Nitsch medium solidified with 0.2% Phytagel. Germination percentage and the length of the sprouts were determined after 72 hours. Germination percentage of lettuce seeds was greatly reduced by the irradiation, and that of the green onion and cucumber were moderately reduced or unchanged by the irradiation. Although average length of the lettuce sprouts was reduced severely, that of the green onion and cucumber was unchanged or moderately reduced. Conclusively, electron beam irradiation might be a useful way of disinfecting some plant seeds including green onion and cucumber.

Effect of electron beam irradiation on seed germination

International Nuclear Information System (INIS)

Han, Seunghee; Bae, Youngmin

2013-01-01

Effect of electron beam irradiation on seed germination was investigated in this research. Electron beam of 0.5, 1.0, 1.5 and 2.0 kGy was irradiated to the seeds of lettuce, green onion and cucumber, and the irradiated seeds were incubated at 25 .deg. Cn Nitsch medium solidified with 0.2% Phytagel. Germination percentage and the length of the sprouts were determined after 72 hours. Germination percentage of lettuce seeds was greatly reduced by the irradiation, and that of the green onion and cucumber were moderately reduced or unchanged by the irradiation. Although average length of the lettuce sprouts was reduced severely, that of the green onion and cucumber was unchanged or moderately reduced. Conclusively, electron beam irradiation might be a useful way of disinfecting some plant seeds including green onion and cucumber

Synergistic effects of irradiation of waste-water

International Nuclear Information System (INIS)

Woodbridge, D.D.

1975-01-01

Water is an absolute necessity for all forms of animal and plant life. As man's requirements for water increase, the need for better methods of purification also increase. Technology has been slow to develop new methods of water treatment for the direct utilization of waste-water. Many new construction projects are at a standstill because waste-water treatment methods have not been developed to handle adequately the ever-increasing flow of sewage. Theoretical considerations of the use of high-level radiation in the treatment of waste-water have failed to consider the effects of the hydrated electron, and the potential of the possible synergistic effects of combining chlorine, oxygen and irradiation. An extensive testing programme at the University Center for Pollution Research of the Florida Institute of Technology over the past four years has shown that irradiation of waste-water samples immersed in an aqueous environment provide bacterial kill and reduction in organic pollution far greater than that obtained from theoretical considerations of G values and earlier experiments where the waste samples were not immersed in an aqueous environment. These testing programmes have investigated the synergistic effects of combining oxygen and irradiation. Each of these combined treatments resulted in an increased bacterial kill factor. Tests on Staphylococcus aureus bacteria and faecal streptococcus bacteria indicate that the synergistic effects observed for faecal coliform bacteria also apply to the pathogenic bacteria. A statistical analysis of the data obtained shows the relationships between the various effects on the bacteria. A definite shielding factor from the turbidity of the waste-water has been shown to exist. Synergistic effects have been shown to offset significantly the shielding effects. Optimization of these synergistic effects can greatly increase the effectiveness of irradiation in the treatment of waste-water. (author)

Effectiveness of thermoluminescence analysis to detect low quantity of gamma-irradiated component in non-irradiated mushroom powders

International Nuclear Information System (INIS)

Akram, Kashif; Ahn, Jae-Jun; Shahbaz, Hafiz Muhammad; Jo, Deokjo; Kwon, Joong-Ho

2013-01-01

Gamma-irradiated (0–10 kGy) dried mushrooms (Lentinus edodes) powders were mixed at different ratios (1–10%) in the non-irradiated samples and investigated using photostimulated-luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) techniques. The PSL results were negative for all samples at 1% mixing ratio, whereas intermediate results were observed for the samples containing 5% or 10% irradiated component with the exception (positive) of 10% mixing of 10 kGy-irradiated sample. The ESR analysis showed the presence of crystalline sugar radicals in the irradiated samples but the radiation-specific spectral features were absent in the mixed samples. TL analysis showed the radiation-specific TL glow curves; however, the complicated results were observed at 1% mixing of 2 and 5 kGy-irradiated samples, which required careful evaluations to draw the final conclusion about the irradiation status of the samples. TL ratios could only confirm the results of samples with 5% and 10% mixing of 10 kGy, and 10% mixing of 5 kGy-irradiated components. SEM-EDX analysis showed that feldspar and quartz were major contaminating minerals, responsible for the radiation-specific luminescence characteristics. -- Highlights: ► Detection of irradiated food is important to enforce the applied regulations. ► The effectiveness of TL analysis was investigated to detect irradiated component. ► The TL results were compared with those from PSL and ESR analysis. ► TL analysis was most effective to characterize the irradiation status of samples. ► SEM-EDX analysis showed feldspar and quartz as the main source of TL properties

Effectiveness of thermoluminescence analysis to detect low quantity of gamma-irradiated component in non-irradiated mushroom powders

Energy Technology Data Exchange (ETDEWEB)

Akram, Kashif [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Institute of Food Science and Nutrition, University of Sargodha, Sargodha 40100 (Pakistan); Ahn, Jae-Jun [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Shahbaz, Hafiz Muhammad [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Institute of Food Science and Nutrition, University of Sargodha, Sargodha 40100 (Pakistan); Jo, Deokjo [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kwon, Joong-Ho, E-mail: jhkwon@knu.ac.kr [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

2013-04-15

Gamma-irradiated (0–10 kGy) dried mushrooms (Lentinus edodes) powders were mixed at different ratios (1–10%) in the non-irradiated samples and investigated using photostimulated-luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) techniques. The PSL results were negative for all samples at 1% mixing ratio, whereas intermediate results were observed for the samples containing 5% or 10% irradiated component with the exception (positive) of 10% mixing of 10 kGy-irradiated sample. The ESR analysis showed the presence of crystalline sugar radicals in the irradiated samples but the radiation-specific spectral features were absent in the mixed samples. TL analysis showed the radiation-specific TL glow curves; however, the complicated results were observed at 1% mixing of 2 and 5 kGy-irradiated samples, which required careful evaluations to draw the final conclusion about the irradiation status of the samples. TL ratios could only confirm the results of samples with 5% and 10% mixing of 10 kGy, and 10% mixing of 5 kGy-irradiated components. SEM-EDX analysis showed that feldspar and quartz were major contaminating minerals, responsible for the radiation-specific luminescence characteristics. -- Highlights: ► Detection of irradiated food is important to enforce the applied regulations. ► The effectiveness of TL analysis was investigated to detect irradiated component. ► The TL results were compared with those from PSL and ESR analysis. ► TL analysis was most effective to characterize the irradiation status of samples. ► SEM-EDX analysis showed feldspar and quartz as the main source of TL properties.

Effects on storage life and quality of irradiated mangoes

International Nuclear Information System (INIS)

Pongsuwan, Dara; Therapawa, Wallapa; Akawassapong, Pakinee; Jattanajet, Jumlong.

1982-01-01

Investigations on the effect of irradiation at 50 Krad, hot water treatment at 55 degC 5 min and hot water treatment followed by irradiation were carried out on the mature green Keaw mango to eradicate anthracnose disease development and delay ripening. Before introducing all treatments, mangoes were inoculated by Colletotrichum gloeosporioides. All samples were determined after stored at 10 +- 2 degC and at 85% RH for 3 weeks. No difference in disease control between untreated and irradiated batches, but fruits treated with hot water followed by irradiation were significantly different from untreated ones. All treatments were effective in delaying ripening. Higher dosage of irradiation with a combination of hot water treatment was studied on colour break Pimsen Prure mango and 75 Krad after hot water treatment proved to be promising. Further study is being conducted

Structural properties and neutron irradiation effects of ceramics

International Nuclear Information System (INIS)

Yano, Toyohiko

1994-01-01

In high temperature gas-cooled reactors and nuclear fusion reactors being developed at present, various ceramics are to be used in the environment of neutron irradiation for undertaking important functions. The change of the characteristics of those materials by neutron irradiation must be exactly forecast, but it has been known that the response of the materials is different respectively. The production method of ceramics and the resulted structures of ceramics which control their characteristics are explained. The features of covalent bond and ionic bond, the synthesis of powder and the phase change by heating, sintering and sintering agent, and grain boundary phase are described. The smelling of ceramics by neutron irradiation is caused by the formation of the clusters of Frenkel defects and minute spot defects. Its restoration by annealing is explained. The defects remaining in materials after irradiation are the physical defects by flipping atoms cut due to the collision with high energy particles and the chemical defects by nuclear transformation. Some physical defects can be restored, but chemical defects are never restored. The mechanical properties of ceramics and the effect of irradiation on them, and the thermal properties of ceramics and the effect of irradiation on them are reported. (K.I.)

The effect of low-dose X-irradiation on immune system

International Nuclear Information System (INIS)

Ishii, Keiichiro

1996-01-01

The hypothesis of radiation hormesis has been proposed. To elucidate the hormetic effect on the immune system, we studied the mitogen-induced proliferation of splenocytes of F344/NSlc rat and BALB/c mouse after low-dose X-irradiation. Con A, PHA or LPS-induced proliferation of rat splenocytes prepared at 4 hr after irradiation was augmented with 5 cGy. This augmentation was observed within a few hours after irradiation, being a temporary effect. In case of mice, the proliferation of splenocytes induced by Con A, PHA or LPS was augmented by irradiation with 2.5 cGy. Thus, some phenomena of hormetic effect on the immune system were observed. However, the mechanism of augmentation of immune splenocytes is uncertainty. Therefore, we examined changes in production of LTB 4 and IL-1 being inflammatory mediators. After 5 cGy irradiation the production of LTB 4 of rat splenocyte showed a significant increase. Furthermore, 2.5 cGy irradiation also enhanced, the biological activity of intracellular IL-1 of LPS-stimulated mouse splenocytes. Additionally, to elucidate the stimulative effect on the antitumor immunity by low-dose X-irradiation, we studied the changes in the incidence of thymic lymphoma using AKR mice and of spontaneous metastasis to lung using tumor bearing mice. The incidence of thymic lymphoma was significantly decreased and the life span was significantly prolonged by periodical low-dose X-irradiation in terms of breeding of AKR mice. By an irradiation with 15 cGy, numbers of lung colony in the tumor bearing mice were decreased by 57% relative to the sham-irradiated controls. Then, IL-6 and TNF-α production of tumor bearing mice splenocytes were enhanced. These findings suggest that the low-dose X-irradiation might have caused a light inflammation and might have induced an augmentation of immune splenocytes. Furthermore, these results indicate that an augmentation of the antitumor immunity was induced by low-dose X-irradiation. (author). 127 refs

The effect of low-dose X-irradiation on immune system

Energy Technology Data Exchange (ETDEWEB)

Ishii, Keiichiro [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab.

1996-06-01

The hypothesis of radiation hormesis has been proposed. To elucidate the hormetic effect on the immune system, we studied the mitogen-induced proliferation of splenocytes of F344/NSlc rat and BALB/c mouse after low-dose X-irradiation. Con A, PHA or LPS-induced proliferation of rat splenocytes prepared at 4 hr after irradiation was augmented with 5 cGy. This augmentation was observed within a few hours after irradiation, being a temporary effect. In case of mice, the proliferation of splenocytes induced by Con A, PHA or LPS was augmented by irradiation with 2.5 cGy. Thus, some phenomena of hormetic effect on the immune system were observed. However, the mechanism of augmentation of immune splenocytes is uncertainty. Therefore, we examined changes in production of LTB{sub 4} and IL-1 being inflammatory mediators. After 5 cGy irradiation the production of LTB{sub 4} of rat splenocyte showed a significant increase. Furthermore, 2.5 cGy irradiation also enhanced, the biological activity of intracellular IL-1 of LPS-stimulated mouse splenocytes. Additionally, to elucidate the stimulative effect on the antitumor immunity by low-dose X-irradiation, we studied the changes in the incidence of thymic lymphoma using AKR mice and of spontaneous metastasis to lung using tumor bearing mice. The incidence of thymic lymphoma was significantly decreased and the life span was significantly prolonged by periodical low-dose X-irradiation in terms of breeding of AKR mice. By an irradiation with 15 cGy, numbers of lung colony in the tumor bearing mice were decreased by 57% relative to the sham-irradiated controls. Then, IL-6 and TNF-{alpha} production of tumor bearing mice splenocytes were enhanced. These findings suggest that the low-dose X-irradiation might have caused a light inflammation and might have induced an augmentation of immune splenocytes. Furthermore, these results indicate that an augmentation of the antitumor immunity was induced by low-dose X-irradiation. 127 refs.

Unscheduled DNA synthesis after β-irradiation of mouse skin in situ

International Nuclear Information System (INIS)

Ootsuyama, Akira; Tanooka, Hiroshi

1986-01-01

The skin of ICR mouse was irradiated with β-rays from 90 Sr- 90 Y with surface doses up to 30 krad. Unscheduled DNA synthesis (UDS) was measured by autoradiography after labeling the skin with radioactive thymidine using the forceps-clamping method. The level of UDS in epithelial cells of the skin was detected as an increasing function of radiation dose. Fibroblastic cells, compared with epithelial cells and hair follicle cells at the same depth of the skin, showed a lower level of UDS, indicating a lower DNA repair activity in fibroblasts. Cancer risk of the skin was discussed. (Auth.)

Effects of gamma irradiation on antioxidants of medicinal plants

International Nuclear Information System (INIS)

Jetawattana, Suwimol; Chaichantipyuth, Chaiyo

2003-06-01

The antioxidant effect of water extracts from irradiated medicinal plants on inhibition of lipid peroxidation in human plasma was examined. The results presented herein indicate that crude extracts from 29 kinds, 31 extracts, of medicinal plants, irradiated at 10 and 25 kilo gray. showed no significant change in inhibition of lipid peroxidation in plasma induced by gamma irradiation (p<0.05). It also found that extraction yields in some irradiated plants were increased

Effects of gamma irradiation on antioxidants of medicinal plants

Energy Technology Data Exchange (ETDEWEB)

Jetawattana, Suwimol [The irradiation research for agriculture program, Office of Atoms for Peace, BK (Thailand); Chaichantipyuth, Chaiyo [Faculty of Pharmacy, Chulalongkorn University, BK (Thailand)

2003-06-01

The antioxidant effect of water extracts from irradiated medicinal plants on inhibition of lipid peroxidation in human plasma was examined. The results presented herein indicate that crude extracts from 29 kinds, 31 extracts, of medicinal plants, irradiated at 10 and 25 kilo gray. showed no significant change in inhibition of lipid peroxidation in plasma induced by gamma irradiation (p<0.05). It also found that extraction yields in some irradiated plants were increased.

Effect of gamma irradiation on storability of Syrian walnut

Energy Technology Data Exchange (ETDEWEB)

Al-Bachir, M [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Radiation Technology

2001-12-01

Walnut fruits of Baladi variety were irradiated with 0, 0.5, 1.0, 1.5 and 2.0 kGy of gamma irradiation. The irradiated and unirradiated fruits were stored at room temperature (15 to 18 Centigrade) and at a relative humidity of 50 to 70%. Fungal load, proximate composition, chemical changes and sensory properties of nuts were evaluated immediately after irradiation, 6 and 12 months of storage. The results indicated that gamma irradiation reduced the fungal load. Used doses did not cause any significant change in proximate composition of walnuts. Immediately after irradiation, gamma irradiation increased total acidity and decreased iodine value and the volatile basic nitrogen (VBN). whereas, after 12 months of storage, gamma irradiation decreased total acidity and peroxide value and increased iodine value and (VBN). Immediately after irradiation no significant differences were observed between irradiated and non-irradiated samples in flavor and aroma. Whereas, after 12 months of storage higher doses (1.5 and 2.0 kGy) had a negative effect on sensory characteristics. (author)

Effect of gamma irradiation on storability of Syrian walnut

International Nuclear Information System (INIS)

Al-Bachir, M.

2002-01-01

Walnut fruits of Baladi variety were irradiated with 0, 0.5, 1.0, 1.5 and 2.0 kGy of gamma irradiation. The irradiated and unirradiated fruits were stored at room temperature (15 to 18 Centigrade) and at a relative humidity of 50 to 70%. Fungal load, proximate composition, chemical changes and sensory properties of nuts were evaluated immediately after irradiation, 6 and 12 months of storage. The results indicated that gamma irradiation reduced the fungal load. Used doses did not cause any significant change in proximate composition of walnuts. Immediately after irradiation, gamma irradiation increased total acidity and decreased iodine value and the volatile basic nitrogen (VBN). whereas, after 12 months of storage, gamma irradiation decreased total acidity and peroxide value and increased iodine value and (VBN). Immediately after irradiation no significant differences were observed between irradiated and non-irradiated samples in flavor and aroma. Whereas, after 12 months of storage higher doses (1.5 and 2.0 kGy) had a negative effect on sensory characteristics. (author)

Irradiation Effects of Electron Beam on Optical Fibers

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Kyu; Cho, Gyu Seong [KAIST, Daejeon (Korea, Republic of); Choi, Hong Gu; Oh, Kyung Hwan [Yonsei University, Seoul (Korea, Republic of); Cho, Ho Jin [Nucron Co. Ltd., Seoul (Korea, Republic of)

2009-10-15

The surveillance or monitoring systems used in space station, nuclear power plant and nuclear waste repository, are often equipped with optical fibers to remotely locating expensive camera systems so as to protect them from direct irradiation. Especially in nuclear power plant and nuclear waste repository, irradiation by gamma-ray and beta-ray are most concerned. The effective life-time of such surveillance system may depend on the soundness of the optical fiber because it is the component to be exposed the high intensity of radiation field by purpose. Though the degradation of mechanical properties such as hardness and elasticity may occur but the degradation of the optical property such as spectral transmittance is the most possible cause of the effective life-time limitation. Generally 30 % reduction of light signal transmittance is considered as the life-time threshold point of such optical systems. In this paper, we studied irradiation effects on spectral transparency of various commonly-used optical fibers with high energy electron beam to conveniently simulate the both gamma-ray and beta-ray irradiation situation.

Effects of gamma irradiation on deteriorated paper

Science.gov (United States)

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

2016-08-01

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

Irradiation of graphene field effect transistors with highly charged ions

Energy Technology Data Exchange (ETDEWEB)

Ernst, P.; Kozubek, R.; Madauß, L.; Sonntag, J.; Lorke, A.; Schleberger, M., E-mail: marika.schleberger@uni-due.de

2016-09-01

In this work, graphene field-effect transistors are used to detect defects due to irradiation with slow, highly charged ions. In order to avoid contamination effects, a dedicated ultra-high vacuum set up has been designed and installed for the in situ cleaning and electrical characterization of graphene field-effect transistors during irradiation. To investigate the electrical and structural modifications of irradiated graphene field-effect transistors, their transfer characteristics as well as the corresponding Raman spectra are analyzed as a function of ion fluence for two different charge states. The irradiation experiments show a decreasing mobility with increasing fluences. The mobility reduction scales with the potential energy of the ions. In comparison to Raman spectroscopy, the transport properties of graphene show an extremely high sensitivity with respect to ion irradiation: a significant drop of the mobility is observed already at fluences below 15 ions/μm{sup 2}, which is more than one order of magnitude lower than what is required for Raman spectroscopy.

Defense of cutaneous cells against uv irradiation. II. Restricted photomediated binding of trimethyl psoralen to pigmented skin in vivo

International Nuclear Information System (INIS)

Carter, D.M.; Jegasothy, B.V.; Condit, E.S.

1973-01-01

Distinct differences in grain distribution were seen in autoradiographs of pigmented and nonpigmented skin from spotted guinea-pig ears subjected to photosensitizing conditions by the topical application of tritiated trimethyl psoralen ( 3 H TMP) and exposure to uv irradiation at 365 nm. Grains were localized over cells throughout the epidermis in nonpigmented skin, but they were not seen beneath the stratum corneum in pigmented skin. Since TMP covalently binds to epidermal nucleic acids only after irradiation, these experiments demonstrate that the compacted melanized cells of the outer epidermis shield the DNA of underlying cells by severely restricting the penetration of uv light into the skin. (auth)

Effects of residual stress on irradiation hardening in stainless steels

Energy Technology Data Exchange (ETDEWEB)

Okubo, N.; Kondo, K.; Kaji, Y. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Miwa, Y. [Nuclear Energy and Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Ibaraki-ken (Japan)

2007-07-01

Full text of publication follows: Structural materials in fusion reactor with water cooling system will undergo corrosion in aqueous environment and heavier irradiation than that in LWR. Irradiation assisted stress corrosion (IASCC) may be induced in stainless steels exposed in these environment for a long term of reactor operation. The IASCC is considered to be caused in a welding zone. It is difficult to predict and estimate the IASCC, because several irradiation effects (irradiation hardening, swelling, irradiation induced stress relaxation, etc) work intricately. Firstly, effects of residual stress on irradiation hardening were investigated in stainless steels. Specimens used in this study were SUS316 and SUS316L. By bending deformation, the specimens with several % plastic strain, which corresponds to weld residual stress, were prepared. Ion irradiations of 12 MeV Ni{sup 3+} were performed at 330, 400 and 550 deg. C to 45 dpa in TIARA facility at JAEA. No bent specimen was simultaneously irradiated with the bent specimen. The residual stress was estimated by X-ray residual stress measurements before and after the irradiation. The micro-hardness was measured by using nano-indenter. The irradiation hardening and the stress relaxation were changed by irradiation under bending deformation. The residual stress did not relax even for the case of the higher temperature aging at 500 deg. C for the same time of irradiation. The residual stress after ion irradiation, however, relaxed at these experimental temperatures in SUS316L. The hardness was obviously suppressed in bent SUS316L irradiated at 300 deg. C to 6 or 12 dpa. It was evident that irradiation induced stress relaxation occasionally suppressed the irradiation hardening in SUS316L. (authors)

Immunological effects of irradiation: waiting for a model

International Nuclear Information System (INIS)

Doria, G.

1979-01-01

Decreased resistance to pathogens, is an effect of ionizing radiations, is largely mediated by impairment of the specific immune response. It has been established that the antibody response is depressed when the antigen is injected shortly before or immediately after irradiation. Recovery of the response in animals immunized after sublethal irradiation starts after about 1 week and may be complete 2 months after irradiation. If animals are immunized a few or several days before radiation exposure, some parameters of the antibody response are unaffected while others may display lower or higher values than normal, depending on the nature and physical form of the antigen. Recent studies have described the effects of whole-body irradiation on antibody ability. Since this antibody property affects the stability of immune complexes and, therefore, the antibody's ability to neutralize viruses and toxins, affinity was felt to be of importance to counteract infections in irradiated animals. Antibody affinity was found up to 20 times greater in irradiated than in control mice when antigen was injected 1 to 5 days before or 2 hr to 8 weeks after a sublethal dose of x-rays. Recovery profiles of mitotic responses of spleen cells to PHA, ConA, or LPS suggest that the enhancement of antibody affinity in irradiated mice could result from a relative lack of suppressor T cells. Dysfunctions of the immune system of irradiated animals can be attributed to alterations of the populations of immunologically competent cells. Unlike auxiliary cells, lymphocytes are extremely sensitive to ionizing radiations. Subpopulations of T and B lymphocytes appear to have different radiosensitivities and to develop with different efficiencies in irradiated animals. B cells seem to be more radiosensitive and to recover faster than T cells

The anti-tumor effect of ACNU and x-irradiation on mouse glioma

International Nuclear Information System (INIS)

Nakagawa, Hidemitsu; Hori, Masaharu; Hasegawa, Hiroshi; Mogami, Heitaro; Hayakawa, Toru.

1979-01-01

Anti-tumor activities of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and x-irradiation on methylcholanthrene induced glioma in C 57 BL mice were studied in vitro and in vivo. In vitro experiments using cultured glioma cells (MGB cells), the synchronization of cell cycle was done by excess addition of thymidine, and the anti-tumor cell effect were investigated by mean of determinations of DNA synthesis, mitotic index and the number of the living cells following the treatments. As the results, it appeared obvious that ACNU was most effective on MGB cells in S phase and x-irradiation in M phase. As to the combined therapy of ACNU and x-irradiation, the anti-tumor effect was most remarkable when the cells were treated by x-irradiation in the G 2 , M phase, which were hervested by addition of ACNU 44 hours before irradiation. However simultaneous treatment of ACNU and x-irradiation on the cells in G 1 phase was not so remarkable. In vivo experiments the anti-tumor effect of ACNU and x-irradiation on subcutaneously or intracranially transplanted glioma in mice was investigated. Either ACNU 10 mg/kg or local x-irradiation 1240 rads showed inhibitory effect on the tumor growth and prolonged the survival time of the tumor bearing mice. The combination therapy was more effective than ACNU or x-irradiation alone, particularly combination therapy of ACNU and repeated small doses irradiation of x-ray was remarkably effective. Evidence obtained indicated that the combination therapy of ACNU and x-irradiation have synergistic anti-tumor effect on experimental mouse glioma. (author)

Search for the lowest irradiation dose from literatures on radiation-induced cancer in uterus

International Nuclear Information System (INIS)

Yoshizawa, Yasuo; Kusama, Tomoko

1975-01-01

A survey of past case reports on radiation-induced cancer of the uterus was carried out with the main object of finding the lowest irradiation dose. Search of literature published since 1912 revealed 548 cases of radiation-induced cancer of the uterus. All of these cases of radiation-induced cancer had received radiation for the treatment of non-malignant disease. The primary gynecological conditions which were the object of radiation therapy were functional bleeding, endometrial hyperplasia, myoma, endometritis, and polyps. The lowest irradiation dose was estimated at 1000-1450 rad in the case of external X-ray irradiation, and 100 mg.hr for intrauterine radium therapy, which corresponds to 100-1000 rad. It was noted that were more cases of corpus cancer than cervical cancer. Histopathological findings of radiation-induced uterine cancer were carcinoma, sarcoma, and mixed mesodermal tumors. The latent period was distributed in the range of 1 to 40 years, with the average of 10.1 years. (auth.)

The irradiation effects of ultraviolet rays on Leptospira cells

International Nuclear Information System (INIS)

Maeda, Hidezo

1982-01-01

The irradiation effects of ultraviolets rays (UV) on leptospira cells were investigated. Four serovar strains of Genus Leptospira ; L. copenhageni, L. canicola, L. biflexa and L. illini were used. A sterilization lamp (Toshiba-GL-15) were lighted at intervals of 90mm on the sample fluid for several minutes. Loss of motility, survival growth and morphological damages were recognized under several conditions. The medium conditions were important, that is, the Korthof's medium was less effective than phosphate buffered saline (PBS). The irradiation time was also important, that is, L. canicola cells in PBS lost their motility and survive ability within 300sec. of irradiation, however, much more time, such as 1.200sec. was necessary in Korthof's medium. This phenomenon may be depended upon defensibility of albumin in the latter. Among the strains, L. biflexa cells showed the highest resistance in loss of motility and survive ability, and other three strains were inferior. The remarkable efects of cellular structures were also seen in the materials with 30 min. of irradiation, in both immediate time or after 24h incubation. The damages observed after 24th of irradiation were much more drastic than those of immediate time. No effect could be seen on the cells suspended in the Korthof's medium irradiated for 24h. Regarding morphological effect, there appeared relaxation of helical body, spherical body and semighost as the immediate changes. Structural damages were recognized as the collapse of cell body, such as scattering of capsule, release of axial flagella, loss or change of cytoplasmic density and break down of wall membrane complex. These phenomena were regarded as the indirect effects of UV-irradiation and autolysis in a post-mortem change. (author)

Effect of low dose x-irradiation on alloantigen sensitized and unsensitized lymphocytes

Energy Technology Data Exchange (ETDEWEB)

Dohi, Kiyohiko; Yahata, Hiroshi; Fukuda, Yasuhiko; Asahara, Toshimasa; Ono, Eiji; Ezaki, Haruo

1984-12-01

The effect of local graft irradiation on immune response in allograft in which acute rejection occurs was studied using an in vitro model. Unidirectional mixed lymphocyte culture (MLC) was used as the in vitro model of acute rejection. 150 and 300 rad x-irradiation suppressed mixed lymphocyte reaction (MLR) but did not cell-mediated-lympholysis (CML) of unsensitized lymphocytes. X-irradiated alloantigen sensitized cells (ASC) generated in 6-day MLC suppressed MLR and CML of unsensitized lymphocytes. Suppressive effects of x-irradiated ASC were of the same degree by x-irradiation doses of 150-500 rad. Suppressive effect of x-irradiation was maintained for only a short period after x-irradiation. Potential function of suppressor precursor cells among unsensitized lymphocytes was abolished by x-irradiation of 300 rad. (author).

Effects of low priming dose irradiation on cell cycle arrest of HepG2 cells caused by high dose irradiation

International Nuclear Information System (INIS)

Xia Jingguang; Jin Xiaodong; Chinese Academy of Sciences, Beijing; Li Wenjian; Wang Jufang; Guo Chuanling; Gao Qingxiang

2005-01-01

Human hepatoma cells hepG2 were irradiated twice by 60 Co γ-rays with a priming dose of 5 cGy and a higher dose of 3 Gy performed 4h or 8h after the low dose irradiation. Effects of the priming dose irradiation on cell cycle arrest caused by high dose were examined with flow cytometry. Cells in G 2 /M phase accumulated temporarily after the 5 cGy irradiation, and proliferation of tumor cells was promoted significantly by the low dose irradiation. After the 3 Gy irradiation, G 2 phase arrest occurred, and S phase delayed temporally. In comparison with 3 kGy irradiation only, the priming dose delivered 4h prior to the high dose irradiation facilitated accumulation of hepG2 cells in G 2 /M phase, whereas the priming dose delivered 8h prior to the high dose irradiation helped the cells to overcome G 2 arrest. It was concluded that effects of the priming dose treatment on cell cycle arrest caused by high dose irradiation were dependent on time interval between the two irradiations. (authors)

Proton irradiation effects on beryllium – A macroscopic assessment

Energy Technology Data Exchange (ETDEWEB)

Simos, Nikolaos, E-mail: simos@bnl.gov [Nuclear Sciences & Technology Department, Brookhaven National Laboratory, Upton, NY, 11973 (United States); Elbakhshwan, Mohamed [Nuclear Sciences & Technology Department, Brookhaven National Laboratory, Upton, NY, 11973 (United States); Zhong, Zhong [Photon Sciences, NSLS II, Brookhaven National Laboratory, Upton, NY, 11973 (United States); Camino, Fernando [Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973 (United States)

2016-10-15

Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting its lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This paper focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.

Emulation of neutron irradiation effects with protons: validation of principle

International Nuclear Information System (INIS)

Was, G.S.; Busby, J.T.; Allen, T.; Kenik, E.A.; Jensson, A.; Bruemmer, S.M.; Gan, J.; Edwards, A.D.; Scott, P.M.; Andreson, P.L.

2002-01-01

This paper presents the results of the irradiation, characterization and irradiation assisted stress corrosion cracking (IASCC) behavior of proton- and neutron-irradiated samples of 304SS and 316SS from the same heats. The objective of the study was to determine whether proton irradiation does indeed emulate the full range of effects of in-reactor neutron irradiation: radiation-induced segregation (RIS), irradiated microstructure, radiation hardening and IASCC susceptibility. The work focused on commercial heats of 304 stainless steel (heat B) and 316 stainless steel (heat P). Irradiation with protons was conducted at 360 deg. C to doses between 0.3 and 5.0 dpa to approximate those by neutron irradiation at 275 deg. C over the same dose range. Characterization consisted of grain boundary microchemistry, dislocation loop microstructure, hardness as well as stress corrosion cracking (SCC) susceptibility of both un-irradiated and irradiated samples in oxygenated and de-oxygenated water environments at 288 deg. C. Overall, microchemistry, microstructure, hardening and SCC behavior of proton- and neutron-irradiated samples were in excellent agreement. RIS analysis showed that in both heats and for both irradiating particles, the pre-existing grain boundary Cr enrichment transformed into a 'W' shaped profile at 1.0 dpa and then into a 'V' shaped profile between 3.0 and 5.0 dpa. Grain boundary segregation of Cr, Ni, Si, and Mo all followed the same trends and agreed well in magnitude. The microstructure of both proton- and neutron-irradiated samples was dominated by small, faulted dislocation loops. Loop size distributions were nearly identical in both heats over a range of doses. Saturated loop size following neutron irradiation was about 30% larger than that following proton irradiation. Loop density increased with dose through 5.0 dpa for both particle irradiations and was a factor of 3 greater in neutron-irradiated samples vs. proton-irradiated samples. Grain boundary

Effect of gamma-irradiation on oocysts of Eimeria necatrix

International Nuclear Information System (INIS)

Singh, J.; Gill, B.S.

1975-01-01

Effect of γ radiation on oocysts of Eimeria necatrix was investigated. It was observed that oocysts exposed to 200kR or above did not sporulate. Irradiation at 10 to 150kR caused a progressive decrease in sporulation. Irradiation affected normal development of unsporulated oocysts as the zygote protoplasm divided into unequal masses or was shattered into granules. Increase in the intensity of irradiation of sporulated oocysts resulted in the progressive decrease in severity of the resultant infections in chicks and their effects - mortality, type of lesions developed, total oocyst production and immunity produced - were comparable with infections induced by decreasing the number of unirradiated oocysts. Infection produced by 1000 unirradiated oocysts was comparable with that resulting from 50,000 oocysts irradiated at 25kR. Infection obtained with 20,000 unexposed oocysts approximated to that produced by 50,000 oocysts irradiated at 2.5kR. It was concluded that irradiation abolished infectivity of the oocysts/sporozoites rather than bringing about attenuation of the parasite. (author)

Effect of UV-irradiation on rotavirus

International Nuclear Information System (INIS)

Smirnov, Y.A.; Kapitulets, S.P.; Kaverin, N.V.; Amitina, N.N.; Ginevskaya, V.A.

1991-01-01

The effect of UV-irradiation on the infectivity of the SAll rotavirus was examined. The time behavior of the inactivation of infectivity generally exhibited the one-hit pattern. The effect was studied with respect to two phenomena, viz. the RNA-protein linkage and the formation of uracil dimers. To determine the number of the latter, purified 3 H-uridine-labelled rotavirus was exposed to UV radiation, and the RNA was extracted and analyzed by paper chromatography in the ascending mode. The formation of photodimers was found to be an important mechanism in the rotavirus inactivation on conventional irradiation, whereas RNA-protein linkages were observed on the application of high doses only. (author). 3 figs., 10 refs

Effect of gamma irradiation on Hom Tong banana

International Nuclear Information System (INIS)

1971-01-01

This report contains research on the use of gamma irradiation to retard the ripening and extend the shelf life of bananas. The major concerns were the effects that irradiation would have on the nutritional content, the organoleptic properties and the pigment of the fruit

The effect of ionizing radiation and bleomycin on transfecting ability of Bacillus subtilis phage DNA

International Nuclear Information System (INIS)

Schafers, F.; Kohnlein, W.

1979-01-01

Infectious DNA of Bacillus subtilis phage 029 and SPP1 has been subjected to ionizing radiation and/or bleomycin treatment. The extent of degradation of the treated DNA was determined on sucrose gradients and biological activity was analyzed using the transfection principle. It was found that loss of biological activity following irradiation or bleomycin treatment of the DNA cannot be accounted for by the production of single- or double-strand breaks. Furthermore, it was observed that pre-irradiation exhibits a synergistic effect on loss of biological activity and production of strand breaks following bleomycin treatment. The authors propose here a simple system capable of detecting biological damage in DNA following irradiation doses as low as 0.5 Gy prior to bleomycin treatment. (Auth.)

Effect of irradiation on vitamin C and acidity

International Nuclear Information System (INIS)

Jiravatana, V.

1971-01-01

Effect of gamma radiation on the total carbohydrates content of Hom Tong banana stored for various time was discussed. The total carbohydrates of unirradiated banana increased more rapidly during storage than those of irradiated ones. Radiation did not appear to have any effect on the total carbohydrate content in the banana. No significant difference was found on the total carbohydrates between irradiated and unirradiated banana at the same stage of ripeness

Effects of irradiation on the gelation properties of muscle protein

International Nuclear Information System (INIS)

Lin Xianping; Yang Wenge

2014-01-01

Gel properties of muscle protein are the important functional characteristics in meat and its products. which determine the meat products' unique quality. such as texture. Juiciness. fat content and sensory characteristics As a novel food preservation technique, irradiation may lead to changes in the composition and structure of protein molecule. and impact the gel forming ability and gelation properties of muscle protein. Based on the introduction of gel forming mechanism of muscle protein, effects of irradiation on the water holding capacity, mechanical properties and structure of muscle protein gel were reviewed in detail. High-dose irradiation could weaken the water holding capacity of muscle protein and result in the loss of meat juice. With different irradiation conditions or raw materials, influences of irradiation on the texture and theological properties of muscle protein gels are varied, and effects on the structure of muscle protein and its gel are more complex. Finally, the research trend of irradiation effects on the gelation properties of muscle protein is put forward. (authors)

A comparison of effects between accelerated heavy ion irradiation and X-irradiation on the development of rat cerebellum

International Nuclear Information System (INIS)

Inouye, Minoru; Hayasaka, Shizu; Murata, Yoshiharu; Takahashi, Sentaro; Kubota, Yoshihisa

1999-01-01

The purpose of this experiment is to compare the effects of 290 MeV/u carbon-ion irradiation and X-irradiation on the development of rat cerebellum. Pregnant rats were exposed to carbon-ion beams at a single dose of 1.5 Gy on day 19.0 of gestation. Other groups of pregnant rats were exposed to X-rays on day 19.0 at single doses of 1.5, 2.0 and 2.5 Gy. Their fetuses were removed 8 hr after exposure, and an acute effect examined microscopically for cell death in the external granular layer of the cerebellum. Other dams were allowed to give birth and rear their litters. The offspring were sacrificed at 6 weeks of age, and their cerebella were examined for foliar malformation. The results showed that the effect of 1.5 Gy carbon-ion irradiation on the development of cerebellum was stronger than that of 1.5 Gy X-irradiation and similar to 2.0-2.5 Gy X-irradiation. (author)

Effect of neutron irradiation on p-type silicon

International Nuclear Information System (INIS)

Sopko, B.

1973-01-01

The possibilities are discussed of silicon isotope reactions with neutrons of all energies. In the reactions, 30 Si is converted to a stable phosphorus isotope forming n-type impurities in silicon. The above reactions proceed as a result of thermal neutron irradiation. An experiment is reported involving irradiation of two p-type silicon single crystals having a specific resistance of 2000 ohm.cm and 5000 to 20 000 ohm.cm, respectively, which changed as a result of irradiation into n-type silicon with a given specific resistance. The specific resistance may be pre-calculated from the concentration of impurities and the time of irradiation. The effects of irradiation on other silicon parameters and thus on the suitability of silicon for the manufacture of semiconductor elements are discussed. (J.K.)

Effects of Irradiation on Insect Host-Parasite Relationship

Energy Technology Data Exchange (ETDEWEB)

Rahalkar, G. W.; Ramakrishnan, V. [Biology Division, Bhabha Atomic Research Centre, Trombay, Bombay (India)

1968-06-15

Effects of host irradiation on the development of its parasite were investigated. Females of Bracon brevicomis readily accepted irradiated larvae of tile wax moth (Galleria mellonella) and rice moth (Corcyra cephalonica) for oviposition. However, irradiated wax moth larvae adversely influenced the viability of eggs laid on them and also the survival of the parasite grubs feeding on their bodies. The female grubs were affected more than the males. Rice moth larvae, on the other hand, exerted no significant influence on the viability of parasite eggs, but adversely affected the survival of the grubs. The progeny of parents that had been reared on irradiated larvae also exhibited some developmental changes although grown on non-irradiated host larvae, and these changes were more pronounced when G. mellonella was used as the host insect. (author)

Effect of soy sauce on lipid oxidation of irradiated pork patties

International Nuclear Information System (INIS)

Kim, Hyun-Wook; Hwang, Ko-Eun; Choi, Yun-Sang; Choi, Ji-Hun; Lee, Mi-Ai; Song, Dong-Heon; Kim, Hack-Youn; Lee, Ju-Woon; Kim, Cheon-Jei

2013-01-01

This study was conducted to find out the antioxidant effect of the soy sauce on lipid oxidation of electron beam irradiated pork patties. The pork patties prepared with sodium chloride or soy sauce solution at identical salt concentrations were irradiated at 0 or 5 kGy, and peroxide value, conjugated diene, 2-thiobarbituric acid, and free fatty acid values were evaluated for 10 days (4 °C). The irradiated pork patties treated with soy sauce showed the lowest peroxide value and 2-thiobarbituric acid value at the end of storage compared to those prepared with sodium chloride. The irradiated pork patties formulated with soy sauce and 0.5% ascorbic acid had similar 2-thiobarbituric acid and free fatty acid values compared to those of the non-irradiated pork patties treated with sodium chloride. Our results suggested that the soy sauce can retard the lipid oxidation of irradiated pork patty, and a synergistic effect between soy sauce and ascorbic acid was observed. - Highlights: • Antioxidant effect of soy sauce on irradiated pork patties was studied. • The soy sauce can retard lipid oxidation of the irradiated pork patties. • A synergistic effect of ascorbic acid for preventing lipid oxidation was observed

Some features of irradiated chitosan and its biological effect

International Nuclear Information System (INIS)

Hai, Le; Hien, Nguyen Quoc; Luan, Le Quang; Hanh, Truong Thi; Man, Nguyen Tan; Ha, Pham Thi Le; Thuy, Tran Thi; Yoshii, Fumio; Kume, Tamikazu

2001-01-01

Preparation of chitosan oligomer by radiation degradation was carried out on the gamma Co-60 source. The radiation degradation yield (G d ) of the chitosan was found to be of 1.03. The oligochitosan with 50% of dp>8 fraction was obtained by irradiating the 10% (w/v) chitosan solution in 5% acetic acid at 45 kGy for the chitosan having the initial viscometric average molecular weight, Mv=60,000. Irradiated chitosan showed higher antifungal effect than that of unirradiated one. Furthermore, the irradiated chitosan also showed the growth-promotion effect for plants. (author)

The sanitary effect of gamma irradiation on sewage sludge

International Nuclear Information System (INIS)

Hess, E.; Breer, C.

1975-01-01

Sludge contains Salmonellae in more than 90% of samples. The maximum number reaches 10 7 per liter. Neither aerobic stabilization nor anaerobic digestion significantly reduces the contamination with Salmonellae. Moreover, Salmonellae in sewage sludge spread on grass may survive up to 72 weeks. Fertilizing with unsanitized sludge may therefore lead to transmission from plant to animal. Sanitizing of sludge to be used as fertilizer is therefore urgent. The sanitary effect of pasteurisation and of gamma irradiation on sewage sludge was investigated. For this the number of Enterobacteriaceae before and after irradiation in 259 specimens of sludge from 44 different sewage disposal plants was examined. The doses applied were 100, 200, 300, 400 and sometimes 500 krad. A linear reduction of Enterobacteriaceae was achieved with increasing radiation doses. A dose of 300 krad resulted in a death rate of 10 4 - 10 8 , occasionally 10 9 Enterobacteriaceae. Less than 10 Enterobacteriaceae per gramm were found in 97.2% of the samples irradiated with 300 krad. The effect found in the above mentioned model experiments could be perfectly confirmed under practical conditions in the irradiation plant of Geiselbullach. The sanitary effect of gamma irradiation with 300-350 krad, determined by Enterobacteriaceae reduction, was equivalent to the effect of heat treatment by pasteurisation. (orig./MG) [de

Low-temperature irradiation of niobium with 15-MeV neutrons

International Nuclear Information System (INIS)

Kerchner, H.R.; Coltman, R.R. Jr.; Klabunde, C.E.; Sekula, S.T.

1978-01-01

Niobium was irradiated at 4.2 K with high energy d-Be neutrons to a fluence of 3.7x10 15 n/cm 2 . The neutrons were generated at the Oak Ridge Isochronous Cyclotron by the breakup reaction of 40-MeV deuterons in a thick Be target. The resulting neutron energy spectrum was broadly peaked near 15 MeV. The 0.012-cm-diameter wire sample (RRR=200) was situated in a uniform transverse magnetic field. The critical current, flux flow resistance, and normal state resistance were measured by using a standard four-terminal technique. The critical current density and the flux flow resistivity were observed to increase with irradiation and to decrease toward the preirradiation values with subsequent isochronal annealing between 4.2 K and 360 K. Using recent theories of flux line lattice deformation, the elementary pinning force is deduced and the result is compared to theoretical calculations. (Auth.)

Pyrimidine dimers in Drosophila chromatin become increasingly accessible after irradiation

International Nuclear Information System (INIS)

Harris, P.V.; Boyd, J.B.

1987-01-01

A prokaryotic DNA-repair enzyme has been utilized as a probe for changes in the accessibility of pyrimidine dimers in Drosophila chromatin following UV irradiation. The results demonstrate a rapid cellular response to physiologically relevant doses of radiation which results in at least a 40% increase in accessible dimers. This increase occurs in two incision-deficient mutants which indicates that the excision-repair process, at or beyond the incision step, is not required or responsible for the increase. In the absence of excision the increase in accessibility persists for a least 2 days following irradiation. The observed increase in accessibility is inhibited by both novobiocin and coumermycin. These inhibitors do not inhibit the initial rate of incision, but do reduce dimer excision measured over more extended periods. A pre-incision process is proposed which actively exposes DNA lesions to excision repair. A fraction of the genome is postulated to be accessible without the intervention of that process. (Auth.)

Heavy ion irradiation effects of polymer film on absorption of light

Energy Technology Data Exchange (ETDEWEB)

Kasai, Noboru; Seguchi, Tadao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Arakawa, Tetsuhito

1997-03-01

Ion irradiation effects on the absorption of light for three types of polymer films; polyethylene-terephthalate (PET), polyethylene-naphthalate (PEN), and polyether-ether-ketone (PEEK) were investigated by irradiation of heavy ions with Ni{sup 4+}(15MeV), O{sup 6+}(160MeV), and Ar{sup 8+}(175MeV), and compared with electron beams(EB) irradiation. The change of absorption at 400nm by a photometer was almost proportional to total dose for ions and EB. The absorption per absorbed dose was much high in Ni{sup 4+}, but rather small in O{sup 6+} and Ar{sup 8+} irradiation, and the absorption by EB irradiation was accelerated by the temperature of polymer film during irradiation. The beam heating of materials during ion irradiation was assumed, especially for Ni ion irradiation. The heavy ion irradiation effect of polymers was thought to be much affected by the ion beam heating than the linear energy transfer(LET) of radiation source. (author)

Radiosensitizers and the oxygen effects in mammalian cells

International Nuclear Information System (INIS)

Millar, B.C.; Fielden, E.M.; Steele, J.J.

1979-01-01

The survival curves for Chinese Hamster cells irradiated under various oxygen tensions have been determined. The variation in OER with oxygen concentration shows two distinct components. Between 1.4 and 7.0 μM the OER is constant with a value of 1.9. Experiments with nitroaromatic radiosensitizers in combination with low concentrations of oxygen show that they can all mimic the 'low concentration' oxygen effect. Of the compounds tested only misonidazole can apparently mimic the 'high concentration' oxygen effect although the full OER cannot be obtained with the authors cell line because of toxicity by the sensitizer. (Auth.)

Effects of gamma irradiation on the performance of Jatropha (Jatropha curcas L.) accessions

Science.gov (United States)

Surahman, M.; Santosa, E.; Agusta, H.; Aisyah, S. I.; Nisya, F. N.

2018-03-01

This study aimed to assess the effects of mutation by using gamma ray on the performance of jatropha plants. The study was conducted at PAIR BATAN. Jatropha seeds obtained from the collection farm of SBRC LPPM IPB and PT Indocement Tunggal Prakarsa Tbk in Gunung Putri, Bogor, were irradiated. The irradiated seeds were grown in Jonggol Trial Farm of IPB. Gamma irradiation was conducted by using a GCM 4000A device. Treatments consisted of irradiation doses, irradiation methods, and accessions. Irradiation doses given were 175, 200, 225 Gy, and no irradiation (control). Irradiation methods consisted of acute, intermittent, and split-dose. Accessions used in this study were Dompu, Medan, Bima, Lombok, ITP II, IP2P, and Thailand. Results of the study were analysed until 5 months after planting showed that gamma ray mutation gave stimulating and inhibiting effects on similar traits. Irradiation dose of 225 Gy was good to be given in acute, intermittent, and split-dose methods. Irradiation effects were found to be significant in jatropha accessions. Effects of irradiation on production will be published soon.

Replicative intermediates in UV-irradiated Simian virus 40

International Nuclear Information System (INIS)

Clark, J.M.; Hanawalt, P.C.

1984-01-01

The authors have used Simian virus 40 (SV40) as a probe to study the replication of UV-damaged DNA in mammalian cells. Viral DNA replication in infected monkey kidney cells was synchronized by incubating a mutant of SV40 (tsA58) temperature-sensitive for the initiation of DNA synthesis at the restrictive temperature and then adding aphidicolin to temporarily inhibit DNA synthesis at the permissive temperature while permitting pre-replicative events to occur. After removal of the drug, the infected cells were irradiated at 100 J/m 2 (254 nm) to produce 6-7 pyrimidine dimers per SV40 genome, and returned to the restrictive temperature to prevent reinitiation of replication from the SV40 origin. Replicative intermediates (RI) were labeled with [ 3 H]thymidine. The size distribution of daughter DNA strands in RI isolated shortly after irradiation was skewed towards lengths less than the interdimer spacing in parental DNA; this bias persisted for at least 1 h after irradiation, but disappeared within 3 h by which time the size of the newly-synthesized DNA exceeded the interdimer distance. Evidence was obtained for the generation at late times after irradiation, of Form I molecules in which the daughter DNA strand contain dimers. Thus DNA strand exchange as well as trans-dimer synthesis may be involved in the generation of supercoiled Form I DNA from 0V-damaged SV40 replicative intermediates. (Auth.)

Late radiation effects in animals surviving lethal irradiation

Energy Technology Data Exchange (ETDEWEB)

Dimitrov, L A

1974-01-01

Animals (rats, mice, dogs) survived lethal irradiation by means of prophylactic-therapeutic treatments or previously irradiated, were studied for late radiation effects: life span, cachexia and fat growing of hypophysical type, tissue or organ hypoplasia manifested by disturbed hemopoiesis, suppressed function of adrenal gland, etc., suppressed immune reactivity of the irradiated organism, atypical biochemical changes in DNA and protein metabolism, epilation, chronic dermatitis, ulcerations, reduced reproductivity or full sterility, damage of kidneys leading to nephrosclerosis, dishormonal states, cataracts, diffuse sclerotic processes, various kinds of malignant and non-malignant tumors. In these cases hemopoiesis compensated for a definite time peripheral blood composition, but during the late period it showed features of incompleteness: shorter life survival of erythrocytes and thrombocytes manifested by a decreased binding of labelled methionine in these blood elements, anemia and relative thrombocytopenia sometimes with an increased number of polychromatic erythrocytes in peripheral blood and a decreased number of reticulocytes at the same time; lymphopenia and relative leucopenia with an increased number of hypersegmented neutrophils. Decreased reproductivity and atypical biochemical changes available in the first generation of the irradiated animals showed the probable role of mutagenic factors in the emergency of some late radiation effects. A significant part of late radiation sequences were due to neuro-endocrine disintegrations. Some of the described late radiation effects were also observed in biological controls as features of ageing. After application of radioprotectors (AET, cysteamine, serotonin) a more marked protective effect is demonstrated in the early reactions (time survival till 30th day, DNA and protein metabolism, immune reactions) of the lethally irradiated animals.

Effect of ion beam irradiation of fresh-keeping of strawberry

International Nuclear Information System (INIS)

Lei Qing; Huang Min; Wu Ling; Mo Yan; Du Xiaoying; Xie Yan; Wang Yan; Gao Peng; Kang Ju

2011-01-01

Effects of ion beam irradiation on strawberry quality were studied, in this study and microbial biomass, decay index, weight loss and biological index were detected. Irradiation dosage were 1.0, 2.0 and 3.0 kGy. The results showed that the irradiation decreased the number of microorganism in the strawberry and delayed the rotten speed. The soluble solide, Vc and total acid content of irradiated strawberry reduced slower than that of control. It indicated that the irradiation dosage did not affect the quality of strawberry in this study . Therefore, 2.0 ∼ 3.0 kGy of ion beam irradiation were an excellent irradiation dosage for strawberry preservation. (authors)

Irradiation effects on aluminium and beryllium

International Nuclear Information System (INIS)

Bieth, M.

1992-01-01

The High Flux Reactor (HFR) in Petten (The Netherlands) is a 45 MW light water cooled and moderated research reactor. The vessel was replaced in 1984 after more than 20 years of operation because doubts had arisen over the condition of the aluminium alloy construction material. Data on the mechanical properties of the aluminium alloy Al 5154 with and without neutron irradiation are necessary for the safety analysis of the new HFR vessel which is constructed from the same material as the old vessel. Fatigue, fracture mechanics (crack growth and fracture toughness) and tensile properties have been obtained from several experimental testing programmes with materials of the new and the old HFR vessel. 1) Low-cycle fatigue testing has been carried out on non-irradiated specimens from stock material of the new HFR vessel. The number of cycles to failure ranges from 90 to more than 50,000 for applied strain from 3.0% to 0.4%; 2) Fatigue crack growth rate testing has been conducted: - with unirradiated specimens from stock material of the new vessel; - with irradiated specimens from the remnants of the old core box. Irradiation has a minor effect on the sub-critical fatigue crack growth rate. The ultimate increase of the mean crack growth rate amounts to a factor of 2. However crack extension is strongly reduced due to the smaller crack length for crack growth instability (reduction of K IC ). - Irradiated material from the core box walls of the old vessel has been used for fracture toughness testing. The conditional fracture toughness values K IQ ranges from 30.3 down to 16.5 MPa√m. The lowermost meaningful 'K IC ' is 17.7 MPa√m corresponding to the thermal fluence of 7.5 10 26 n/m 2 for the End of Life (EOL) of the old vessel. - Testing carried out on irradiated material from the remnants of the old HFR core box shows an ultimate neutron irradiation hardening of 35 points increase of HSR 15N and an ultimate tensile yield stress of 589 MPa corresponding to the

Effect of irradiation on amino acid and sensory quality of braised chicken

International Nuclear Information System (INIS)

Hu Peng; Zhang Qizhi; Deng Peng; Wang Shoujing; Xu Fangzuo

2011-01-01

The effects of irradiation, the packaging methods, antioxidants and irradiation temperature on amino acid composition of braised chicken were studied and the sensory characteristics of irradiated braised chicken at different storage time were evaluated in this paper. Eighteen kinds of amino acids were determined by amino acid analyzer and peculiar smell during the storage was conducted with double blind method. The results showed that the packaging methods, antioxidants and irradiation temperature had no effect on amino acid composition of braised chicken at 6.5 kGy (P>0.05), and the irradiated braised chicken gave off peculiar smells significantly and the peculiar smells gradually lightened with the extension of storage time. Low-temperature irradiation combined with vacuum packaging and antioxidants were an effective method on braised chicken irradiation. (authors)

Effect of irradiation dose and irradiation temperature on the thiamin content of raw and cooked chicken breast meat

International Nuclear Information System (INIS)

Graham, W.D.; Stevenson, M.H.; Stewart, E.M.

1998-01-01

The usefulness of ionising radiation for the elimination of pathogenic bacteria in poultry meat has been well documented as have the effects of this processing treatment on the nutritional status of the food, in particular, the vitamins. Unfortunately, much of the earlier research carried out on the effect of irradiation on vitamins was carried out in solution or in model systems at doses much greater than those used commercially thereby resulting in considerable destruction of these compounds. Thus, those opposed to the process of food irradiation labelled the treated food as nutritionally poor. However, in reality, due to the complexity of food systems the effects of irradiation on vitamins are generally not as marked and many processes, for example cooking, cause the same degree of change to the vitamins. Thiamin (vitamin B1) is the most radiation sensitive of the water-soluble vitamins and is therefore a good indicator of the effect of irradiation treatment. In this study the effects of irradiation at either 4°C or −20°C followed by cooking on the thiamin content of chicken breast meat was determined. Results showed that whilst both irradiation and cooking resulted in a decrease in thiamin concentration, the losses incurred were unlikely to be of nutritional significance and could be further minimised by irradiating the chicken meat at a low temperature. Thiamin analyses were carried out using high-performance liquid chromatography since this technique is faster and more selective than the chemical or microbiological methods more commonly employed. Total thiamin, both free and combined form, was determined following acid and enzyme hydrolysis. © 1998 Society of Chemical Industry

About the study of irradiation effects on in-core instrumentation

International Nuclear Information System (INIS)

Angelino, G.

1972-01-01

The knowledge of in-core instrumentation performances is a very important item when irradiations of technological interest are concerned. When measurement of small changes in mechanical or thermal properties is of major importance, the effect of neutron and gamma irradiation on various transducers must be thoroughly evaluated. A rig mock-up was irradiated in the Triga Mark II Reactor of the Pavia University to assess the possibility of carrying out a study on irradiation effects on in-core instrumentation. Data on neutron flux distribution and γ-heating effect were collected from this preliminary experiment; at the same time a complete check was performed on rig assembling procedure, on the behaviour under operating conditions, and on the reactor loading and unloading operations. (author)

Effects of 60Co irradiation on the genetics of indian meal moth

International Nuclear Information System (INIS)

Yang Changju; Liu Ganming; Deng Wangxi; Yang Zhihui; Hu Jianfang

1993-01-01

4 ∼ 5 days old male pupae of Indian meal moth, Plodia interpunctella Hubner were irradiated with 1, 3, 5, 7 and 10 krad of 60 Co γ-ray. The male moths developed from treated pupae and their F 1 generation were put together with normal female moths for copulation separately. The genetic effects of irradiation was studied and the results showed that the effects of irradiation were significant, which related to the irradiation dosage, on both parental and filial generations. Only 40% of the pupae was emerged, when they were irradiated at 10 krad. The effects on deformation rates, survival rates, copulation abilities, fecundities, hatching rates and genetic sterilities varied with different irradiation dosage treatment. With consideration of the total irradiation effect, the dosage lower than 5 krad is desirable for inducing the sterility of adults and sex chain recessive lethal gene. With 1, 5 and 7 krad of irradiation, a mutant of P. interpunctella with transparent wings was induced, which provides a marking feature in control of Indian meal moth by sex chain recessive lethal gene

Effect of irradiation on biochemistry properties of shrimp allergen

International Nuclear Information System (INIS)

Gu Kefei; Gao Meixu; Li Chunhong; Li Shurong; Pan Jiarong

2007-01-01

Study on the effects of 60 Co γ-rays irradiation at the dose of 0,3,5,7,10 kGy on shrimp allergen biochemistry properties was conducted. The results indicated that the allergen protein molecule can be broken down to smaller molecules or coagulated to larger molecules by irradiation. The hydrophobicity and turbidity of irradiated allergen increased with the increase of absorbed dose. The results also show that allergen solution is more sensitive to irradiation than allergen in solid state or in the whole shrimp. (authors)

Axo-somatic synapses in the normal and X-irradiated dendate gyrus; factors affecting the density of afferent innervation

International Nuclear Information System (INIS)

Lee, K.S.; Gerbrandt, L.; Lynch, G.

1982-01-01

The density of synaptic input to the somata of dentate gyrus granule cells was examined utilizing quantitative electron microscopic techniques. In control (non-irradiated) material, greater numbers of axo-somatic synapses were observed in the superficial, earlier-generated cells as compared to the deep, later-generated cells. We further studied the X-irradiated dentate gyrus, in which the majority of granule cells were destroyed during postnatal genesis. The surviving cells displayed a density of innervation on their somata which exceeded that observed in either layer of the control material. These data are discussed in terms of the possible contribution of afferent-target cell interactions to the regulation of the density of synaptic innervation. (Auth.)

Irradiation spectrum and ionization-induced diffusion effects in ceramics

Energy Technology Data Exchange (ETDEWEB)

Zinkle, S.J. [Oak Ridge National Lab., TN (United States)

1997-08-01

There are two main components to the irradiation spectrum which need to be considered in radiation effects studies on nonmetals, namely the primary knock-on atom energy spectrum and ionizing radiation. The published low-temperature studies on Al{sub 2}O{sub 3} and MgO suggest that the defect production is nearly independent of the average primary knock-on atom energy, in sharp contrast to the situation for metals. On the other hand, ionizing radiation has been shown to exert a pronounced influence on the microstructural evolution of both semiconductors and insulators under certain conditions. Recent work on the microstructure of ion-irradiated ceramics is summarized, which provides evidence for significant ionization-induced diffusion. Polycrystalline samples of MgO, Al{sub 2}O{sub 3}, and MgAl{sub 2}O{sub 4} were irradiated with various ions ranging from 1 MeV H{sup +} to 4 MeV Zr{sup +} ions at temperatures between 25 and 650{degrees}C. Cross-section transmission electron microscopy was used to investigate the depth-dependent microstructural of the irradiated specimens. Dislocation loop nucleation was effectively suppressed in specimens irradiated with light ions, whereas the growth rate of dislocation loops was enhanced. The sensitivity to irradiation spectrum is attributed to ionization-induced diffusion. The interstitial migration energies in MgAl{sub 2}O{sub 4} and Al{sub 2}O{sub 3} are estimated to be {le}0.4 eV and {le}0.8 eV, respectively for irradiation conditions where ionization-induced diffusion effects are expected to be negligible.

Effect of gamma irradiation on thermal inactivation and injury of Bacillus subtilis spores

International Nuclear Information System (INIS)

El-Zawahry, Y.A.; Mostafa, S.A.; Awny, N.M.

1986-01-01

Bacillus subtilis spores which received preliminary irradiation doses were more sensitive to subsequent heating than non-irradiated spores. The thermal inactivation increased by increasing any of exposure temperature, thermal exposure time or preliminary irradiation dose. The thermal (D T -) value was much higher for non-irradiated spores than the D TR value for the pre-thermal irradiated spores. The radiosensitizing effect was directly proportional to the preliminary irradiation dose. The pre-thermal irradiation treatment of B. subtilis spores resulted in a synergistic effect in spore deactivation. This synergistic effect increased gradually by increasing the preliminary irradiation dose and/or the thermal temperature from 60 to 80 0 C, but decreased for 90 0 C and for the longer exposure periods at any of the examined temperature. Thermal injury of B. subtilis spores was more for the non-irradiated than for the irradiated spores

Effect of tumor therapeutic irradiation on the mechanical properties of teeth tissue

International Nuclear Information System (INIS)

Fraenzel, W.; Gerlach, R.; Hein, H.J.; Schaller, H.G.

2006-01-01

Tumor irradiation of the head-neck area is accompanied by the development of a so-called radiation caries in the treated patients. In spite of conservative therapeutic measures, the process results in tooth destruction. The present study investigated the effects of irradiation on the demineralization and remineralization of the dental tissue. For this purpose, retained third molars were prepared and assigned either to a test group, which was exposed to fractional irradiation up to 60 Gy, or to a non-irradiated control group. Irradiated and non-irradiated teeth were then demineralized using acidic hydroxyl-cellulose gel; afterwards the teeth were remineralized using either Bifluorid12 registered or elmex gelee registered . The nanoindentation technique was used to measure the mechanical properties, hardness and elasticity, of the teeth in each of the conditions. The values were compared to the non-irradiated control group. Irradiation decreased dramatically the mechanical parameters of enamel and dentine. In non-irradiated teeth, demineralization had nearly the same effects of irradiation on the mechanical properties. In irradiated teeth, the effects of demineralization were negligible in comparison to non-irradiated teeth. Remineralization with Bifluorid12 registered or elmex gelee registered led to a partial improvement of the mechanical properties of the teeth. The enamel was more positively affected, by remineralization than the dentine. (orig.)

Rescue Effects: Irradiated Cells Helped by Unirradiated Bystander Cells

Science.gov (United States)

Lam, R. K. K.; Fung, Y. K.; Han, W.; Yu, K. N.

2015-01-01

The rescue effect describes the phenomenon where irradiated cells or organisms derive benefits from the feedback signals sent from the bystander unirradiated cells or organisms. An example of the benefit is the mitigation of radiation-induced DNA damages in the irradiated cells. The rescue effect can compromise the efficacy of radioimmunotherapy (RIT) (and actually all radiotherapy). In this paper, the discovery and subsequent confirmation studies on the rescue effect were reviewed. The mechanisms and the chemical messengers responsible for the rescue effect studied to date were summarized. The rescue effect between irradiated and bystander unirradiated zebrafish embryos in vivo sharing the same medium was also described. In the discussion section, the mechanism proposed for the rescue effect involving activation of the nuclear factor κB (NF-κB) pathway was scrutinized. This mechanism could explain the promotion of cellular survival and correct repair of DNA damage, dependence on cyclic adenosine monophosphate (cAMP) and modulation of intracellular reactive oxygen species (ROS) level in irradiated cells. Exploitation of the NF-κB pathway to improve the effectiveness of RIT was proposed. Finally, the possibility of using zebrafish embryos as the model to study the efficacy of RIT in treating solid tumors was also discussed. PMID:25625514

Defect creation rates in CdTe irradiated by electrons

International Nuclear Information System (INIS)

Caillot, M.

1978-01-01

Up to now, the defect creation rates in CdTe irradiated by electrons were unknown. They have been calculated for different electron kinetic energies. As the samples studied are thick, the energy loss when the electrons penetrate the material has been taken into account. The cross-sections of Cd and Te displacements vs the depth of electron penetration were determined for different electron kinetic energies, and the defect creation rates obtained for each sublattice. These creation rates have been compared with those deduced from experiments and it was found that the experimental creation rates were lower than the calculated ones. This discrepancy can be explained in terms of creation of neutral Frenkel pairs. (Auth.)

Irradiation effects test series test IE-1 test results report

International Nuclear Information System (INIS)

Quapp, W.J.; Allison, C.M.; Farrar, L.C.; Mehner, A.S.

1977-03-01

The report describes the results of the first programmatic test in the Nuclear Regulatory Commission Irradiation Effects Test Series. This test (IE-1) used four 0.97m long PWR-type fuel rods fabricated from previously irradiated Saxton fuel. The objectives of this test were to evaluate the effect of fuel pellet density on pellet-cladding interaction during a power ramp and to evaluate the influence of the irradiated state of the fuel and cladding on rod behavior during film boiling operation. Data are presented on the behavior of irradiated fuel rods during steady-state operation, a power ramp, and film boiling operation. The effects of as-fabricated gap size, as-fabricated fuel density, rod power, and power ramp rate on pellet-cladding interaction are discussed. Test data are compared with FRAP-T2 computer model predictions, and comments on the consequences of sustained film boiling operation on irradiated fuel rod behavior are provided

Effect of gamma irradiation on storability of strawberry (Fragaria sp)

Energy Technology Data Exchange (ETDEWEB)

Al-Bachir, M; Farah, S [Atomic Energy Commission, Dept. of Agriculture, Damascus (Syrian Arab Republic)

1998-02-01

Despite the increased production of strawberry in Syria, the storability and marketability of fruits were not well studied. The objectives of this study were to investigate the effect of gamma irradiation on storability of Senga sengana strawberry produced in Syria and the effect of gamma irradiation on fungal sp. i.e. Botrytis; Penicillium; Rhizopus. The fruits were treated with 1 , 2 and 3 KGy of gamma rays. Treated and untreated fruits were stored at 2 to 4 centigrade and 80 to 90 % relative humidity (RH). In order to investigate their marketability, the fruits where held at room temperature (25 to 30 centigrade). Weight loss, microbial decay, and total loss, juice production, pH, total soluble solids of the juice and organoleptic qualities were evaluated throughout the different storage and marketing periods. The results indicate that gamma irradiation decreased the microbial decay and increased the storability and marketability of fruits by 50 and 100% after using 2 and 3 kGy, respectively. D10 were 1.8 and 2.4 for Botrytis and Rhizopus respectively. One day after irradiation total soluble solids and its pH values were increased. Fourteen days later, irradiated fruits produced more juice with higher pH, but total soluble solids were less. Gamma irradiation did not have an effect on aroma and colour of fruits, whereas, 3 kGy of gamma irradiation had an adverse negative effect on taste. (author)

Materials for cold neutron sources: Cryogenic and irradiation effects

International Nuclear Information System (INIS)

Alexander, D.J.

1990-01-01

Materials for the construction of cold neutron sources must satisfy a range of demands. The cryogenic temperature and irradiation create a severe environment. Candidate materials are identified and existing cold sources are briefly surveyed to determine which materials may be used. Aluminum- and magnesium-based alloys are the preferred materials. Existing data for the effects of cryogenic temperature and near-ambient irradiation on the mechanical properties of these alloys are briefly reviewed, and the very limited information on the effects of cryogenic irradiation are outlined. Generating mechanical property data under cold source operating conditions is a daunting prospect. It is clear that the cold source material will be degraded by neutron irradiation, and so the cold source must be designed as a brittle vessel. The continued effective operation of many different cold sources at a number of reactors makes it clear that this can be accomplished. 46 refs., 8 figs., 2 tab

Phytosanitary irradiation and fresh fruit quality: Cultivar and maturity effects

Science.gov (United States)

Irradiation is an effective quarantine treatment for global trade of fresh produce. Variation in cultivars and maturity stages can impact the tolerance of fresh fruits to irradiation for the purposes of quarantine security. Tolerance thresholds for irradiated fruit are lacking for a large number of ...

Adrenaline and serotonin therapeutic effect on the hemopoietic system of irradiated mice

International Nuclear Information System (INIS)

Smirnova, I.B.; Dontsova, G.V.; Rakhmanina, O.N.; Konstantinova, M.M.

1984-01-01

Post-irradiation effect of adrenaline and serotonin on the hemopoietic system of irradiated mice has been studied. The pharmaceuticals were injected subcutaneously 15 minutes before the X-radiation exposure at a dose of 7 Gy or immediately after it. The degree of radiation injury has been estimated from 30-day survival fraction of the animals, cell state of the bone marrow, mass of spleen, cfu quantity in the bone marrow at exo- and endocolonial growth (following implantation of bone marrow cells from mice that had been injected with these drugs to irradiated recipients). Post-irradiation effect of adrenaline turned to be weaker than that of serotonin, the latter increasing the survival rate of irradiated mice to 50%. It is stated that post-irradiation therapeutic effect of adrenaline and serotonin expressed in acceleration of the irradiated hemopoietic tissue repair can be realized under direct effect of drugs on the viable hemopoietic cells, probably, by enchancement of their proliferation

Radiation cancer in man, especially on the cases developed after irradiation for malignant conditions

International Nuclear Information System (INIS)

Kikuchi, Akira

1975-01-01

Twelve cases in which radiation cancer was observed at the Tohoku University are reported. Half of them had been treated for tuberculous cervical lymphadenitis, one for lupus vulgaris and five for various malignant conditions. The average latent period was 27 years in 7 cases which were treated for benign conditions and 13 years in 5 cases treated for malignant conditions. In Japan, 12 cases of radiation cancer after irradiation for malignant conditions, excluding leukemia, have been reported. The clinical features of these 17 cases in addition to 5 cases are reviewed. (auth.)

Influence of X-ray irradiation on metabolic effects of adrenaline

Energy Technology Data Exchange (ETDEWEB)

Szyszko, A [Wojskowy Instytut Higieny i Epidemiologii, Warsaw (Poland)

1976-01-01

Effects of irradiation in the whole-body dose of 650 R on changes in glycogen levels in liver, and in either diaphragm and skeletal muscles, and on blood glucose levels, induced in 10 min by adrenaline, were investigated in starved mice. One day after the exposure, the drops in liver glycogen levels due to starvation were found to be highly reduced by previous irradiation. This resulted in an over dozen-fold relative elevation of liver glycogen content in relation to starved not irradiated mice. The post-irradiation accumulation of liver glycogen was found to disappear after administration of adrenaline. Also in diaphragm and skeletal muscles, the changes in muscle glycogen content, induced by irradiation of starved mice, have turned out to be abolished or even reversed by adrenaline, as reflected in reduction of elevated levels and elevation of those reduced. In starved mice during first three days following irradition, adrenaline was found to be ineffective in increasing blood sugar levels, whereas its effect was noted in either not irradiated mice or on the fourth day after irradiation.

Influence of X-ray irradiation on metabolic effects of adrenaline

International Nuclear Information System (INIS)

Szyszko, A.

1976-01-01

Effects of X-ray irradiation in the whole-body dose of 650 R on changes in glycogen levels in liver, and in either diaphragm and skeletal muscles, and on blood glucose levels, induced in 10 min by adrenaline, were investigated in starved mice. One day after the exposure, the drops in liver glycogen levels due to starvation were found to be highly reduced by previous irradiation. This resulted in an over dozen-fold relative elevation of liver glycogen content in relation to starved not irradiated mice. The post-irradiation accumulation of liver glycogen was found to disappear after administration of adrenaline. Also in diaphragm and skeletal muscles, the changes in muscle glycogen content, induced by irradiation of starved mice, have turned out to be abolished or even reversed by adrenaline, what reflected in reduction of elevated levels and elevation of those reduced. In starved mice during first three days following irradition, adrenaline was found to be ineffective in increasing blood sugar levels, whereas this its effects was noted in either not irradiated mice or on the fourth day after irradiation. (author)

A technique for determining the depth distribution of cavities in He+-irradiated nickel

International Nuclear Information System (INIS)

Fenske, G.; Das, S.K.; Kaminsky, M.

1979-01-01

The authors describe a technique for examining the depth distribution of the damage (i.e., dislocations, bubbles and voids) in 4 He + ion-irradiated nickel. One existing technique is to section the sample parallel to the direction of the incident beam and prepare thin foils suitable for TEM. This technique has been used only in a few instances because of the difficulty in sample preparation, but it has the advantage that the entire depth distribution of damage can be obtained from a single sample. The technique described by the present authors is a modification of this type of technique and allows one to observe the depth distribution of bubbles and of damage in very near surface regions (<0.2μm) with excellent depth resolution and a small (approximately 50 A) uncertainty in locating the irradiated surface. (Auth.)

Reactivity-flooding effect of the MNSR inner irradiation sites

International Nuclear Information System (INIS)

Khamis, I.; Khattab, K.

1999-01-01

For the purpose of safety assessments, evaluation of the reactivity effects of inner irradiation sites, being flooded with water in the MNSR reactor was conducted both numerically and experimentally. Measured and calculated effect of different combination of inner irradiation sites being flooded with water was evaluated numerically and experimentally. Good agreement between measurement and calculated results were obtained

Effect of electron beam irradiation on quality of fresh chilled pork

International Nuclear Information System (INIS)

Shang Yibin; Gao Meixu; Li Shurong; Pei Ying; Wang Zhidong

2013-01-01

The effects of electron beam irradiation on nutrient quality, lipid oxidation and sensory quality of fresh chilled pork were investigated. Fresh chilled pork whose fat to muscle ratio was 1 : 6 was grounded and packaged, and then irradiated at doses of 0, 2.0, 3.8, 6.2, 8.3 and 10.5 kGy. The contents of fat andprotein, chromaticity, sensory characteristics, lipid oxidation index of TBARS value, POV, diene value of irradiated and unirradiated samples were measured. The results showed that there were no significant differences (5% level) in content of proteinand fat between irradiated and control samples, but irradiation could significantly increase TBARS value and POV. EB irradiation enhanced the increase of total diene value. The samples treated with 3.8 and 6.2 kGy showed good color during storage. There were no significant differences in sensory characteristics among different EB doses. It is concluded that 4-6 kGy EB irradiation, which is effective for decontamination, shows no significant effect on qualities of fresh chilled pork. (authors)

UV-irradiation effects on polyester nuclear track detector

International Nuclear Information System (INIS)

Agarwal, Chhavi; Kalsi, P.C.

2010-01-01

The effects of UV irradiation (λ=254 nm) on polyester nuclear track detector have been investigated employing bulk-etch technique, UV-visible spectrophotometry and infra-red spectrometry (FTIR). The activation energy values for bulk-etching were found to decrease with the UV-irradiation time indicating the scission of the polymer. Not much shift in the absorption edge due to UV irradiation was seen in the UV-visible spectra. FTIR studies also indicate the scission of the chemical bonds, thereby further validating the bulk-etch rate results.

Effects of temperature during the irradiation of calcium carbonate

Energy Technology Data Exchange (ETDEWEB)

Negron M, A.; Camargo R, C.; Ramos B, S. [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Gomez V, V. [UNAM, Instituto de Quimica, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Uribe, R. M., E-mail: negron@nucleares.unam.mx [Kent State University, College of Technology, Kent 44240 Ohio (United States)

2015-10-15

The gamma irradiation of calcium carbonate at different doses (0 to 309 kGy) and temperature regimes (77 K to 298 K) was carried out to study the effects of irradiation temperature. The changes were followed by EPR spectroscopy. We observed the formation of a composite EPR spectrum even at low radiation doses and temperature. There is a strong effect on the evaluation of the radicals formed as a function of irradiation temperature, probably due to the diffusion in the frozen powder. Response curves show that this system tends to saturate at 10 MGy at 298 K. (Author)

Effects of temperature during the irradiation of calcium carbonate

International Nuclear Information System (INIS)

Negron M, A.; Camargo R, C.; Ramos B, S.; Gomez V, V.; Uribe, R. M.

2015-10-01

The gamma irradiation of calcium carbonate at different doses (0 to 309 kGy) and temperature regimes (77 K to 298 K) was carried out to study the effects of irradiation temperature. The changes were followed by EPR spectroscopy. We observed the formation of a composite EPR spectrum even at low radiation doses and temperature. There is a strong effect on the evaluation of the radicals formed as a function of irradiation temperature, probably due to the diffusion in the frozen powder. Response curves show that this system tends to saturate at 10 MGy at 298 K. (Author)

Some features of irradiated chitosan and its biological effect

Energy Technology Data Exchange (ETDEWEB)

Hai, Le; Hien, Nguyen Quoc; Luan, Le Quang; Hanh, Truong Thi; Man, Nguyen Tan; Ha, Pham Thi Le; Thuy, Tran Thi [Nuclear Research Institute, VAEC, Dalat (Viet Nam); Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

2001-03-01

Preparation of chitosan oligomer by radiation degradation was carried out on the gamma Co-60 source. The radiation degradation yield (G{sub d}) of the chitosan was found to be of 1.03. The oligochitosan with 50% of dp>8 fraction was obtained by irradiating the 10% (w/v) chitosan solution in 5% acetic acid at 45 kGy for the chitosan having the initial viscometric average molecular weight, Mv=60,000. Irradiated chitosan showed higher antifungal effect than that of unirradiated one. Furthermore, the irradiated chitosan also showed the growth-promotion effect for plants. (author)

Postirradiation examination results for the Irradiation Effects Scoping Test 2

International Nuclear Information System (INIS)

Mehner, A.S.

1977-01-01

The postirradiation examination results are reported for two rods from the second scoping test (IE-ST-2) of the Nuclear Regulatory Commission Irradiation Effects Program. The rods were irradiated in the in-pile test loop of the Power Burst Facility at the Idaho National Engineering Laboratory. Rod IE-005 was fabricated from fresh fuel and cladding previously irradiated in the Saxton Reactor. Rod IE-006, fabricated from fresh fuel and unirradiated cladding, was equipped with six developmental cladding surface thermocouples. The rods were preconditioned, power ramped, and then subjected to film boiling operation. The performance of the rods and the developmental thermocouples are evaluated from the post irradiation examination results. The effects of prior irradiation damage in cladding are discussed in relation to fuel rod behavior during a power ramp and subsequent film boiling operation

The Effect of Gamma Irradiation on The Quality of Egyptian Kareash Cheese

International Nuclear Information System (INIS)

Aly, S; Farage, M. D.; Galal, E.A.

2008-01-01

The effect of gamma irradiation on the quality of kareash cheese was evaluated. Egyptian kareash cheese were subjected to gamma irradiation at different safety doses beginning from 1 kGy to a maximum of 5 kGy . The physico-chemical composition as well as microbiological quality of kareash cheese samples was monitored before and after irradiation. Soluble nitrogen, salt as well as pH values were higher in cheese samples before irradiation in comparison with the irradiated groups. Irradiation reduced population of bacteria i.e. total colony count, Total yeast and mold count, aerobic spore former count, Coliform count, total Enterobacteriacae count and the effect was more pronounced at the highest dose (5 kGy). It could be concluded that increasing the dose of irradiation up to 5 kGy had high reduction percentages for bacterial count with no effect on either sensory or chemical characteristics. Our results suggest that kareash cheese manufacturer could use gamma irradiation to improve the safety of their product. (author)

Effects of gamma irradiation of barley and malt on malting quality

International Nuclear Information System (INIS)

Köksel, H.; ÇElik, S.; ÖZkara, R.

1998-01-01

Two two-rowed barley cultivars, Tokak and Clerine, were irradiated at two different dose ranges (0.05–0.75 kGy and 0.5–5.0 kGy) using a 60Co source. Irradiation of barley at the medium levels before malting had detrimental effects on most of the malt quality criteria. The detrimental effects of irradiation was lower at doses up to 0.25 kGy. Irradiation of malt samples caused either slight or no deterioration of quality characteristics

Communicating the non-targeted effects of radiation from irradiated to non-irradiated cells

International Nuclear Information System (INIS)

Laiakis, E.C.; Morgan, W.F.

2005-01-01

For many years, the central dogma in radiobiology has been that energy deposited in the cell nucleus is responsible for the biological effects associated with radiation exposure. However, non-targeted and delayed effects of radiation have shifted this belief. The studies of radiation-induced genomic instability, the bystander and abscopal effects, clastogenic factors, and the Death Inducing Effect have dominated the interest of the radiobiology field of late. The passing of signals from irradiated to non-irradiated cells can be accomplished through cell-to-cell gap junction communication or secretion of molecules, which in turn can elicit a response through activation of signal transduction pathways. Proposed mediators of this phenotype include proteins involved with inflammation. Given their size and connection with oxidative stress, cytokines are an attractive candidate as mediators of the induction of the non-targeted effects of radiation. Here we review the evidence for a possible connection between these delayed non-targeted effects of radiation and the cytokine cascades associated with inflammation. (author)

Effect of gamma irradiation on physico-chemical charateristics of soybean

International Nuclear Information System (INIS)

Inayatullah; Hussain, B.; Zeb, A.; Ahmad, M.; Khan, I.

1987-01-01

Effect of gamma irradiation (0,25,50,100,250 and 500 Krad) on the physicochemical and cooking characteristics of Crawford, Dawson, Webber, Swat-84, S-76209 and Hobbit varieties of soybean was studied. Irradiation had no significant effect on proximate composition (water, protein, fat, ash, crude fiber, carbohydrate) and important mineral contents (calcium, phosphorous, iron) of soybean. Phytic acid content and cooking time were significantly decreased whereas peroxide value of soybean was significantly increased due to irradiation. (author)

Effects of prenatal ionizing irradiation on neural function and behavior

International Nuclear Information System (INIS)

Brizzee, K.R.; Ordy, J.M.; Pennwalt Corp., Rochester, NY

1986-01-01

Behavioral studies in the past decade on postnatal effects of prenatal ionizing irradiation (125-R) revealed alterations in circadian locomotor activity and modifications of duration, frequency and sequences of certain behavioral acts in irradiated rats. Other studies have shown that the effect of irradiation (150-R) and enriched environment were both significant in initial, repetitive and total error scores while at 200-R enrichment was less effective. Rats irradiated on the 13th, 14th and 15th day of gestation were born with a hopping gait, paired hind and forelimbs moving in unison. Thoracic cord section led to crossed extention hind-limb reflexes in control rats and simultaneus withdrawal of hind limbs in hopping rats, in response to pinprick. In 90 day old squirrel monkeys the percent of correct response in visual orientation, discrimination and reversal learning in 50- and 100-R offspring (Co 60 irradiation at 89-90 days gestation) were significantly lower than those of controls, and differences in reversal learning persisted undiminished at 2 years of age. Time required for body righting, head-up orientation and climbing at 45 0 incline was significantly greater in irradiated (mainly 100-R) than control animals at from 2 to 28 days of age. Visual acuity levels of 50- and 100-R 30 day old infants were significantly lower than in control infants. Stabilimeter activity in the dark was significantly higher in 50- and 100-R 30 day old infants than in controls. In the squirrel monkey studies effects of Co 60 irradiation (100-R) on postnatal development of the brain and behaviour can be identified at statistically significant levels of confidence independent of offspring nursery rearing effects. (orig.)

Silicon/HfO2 interface: Effects of proton irradiation

International Nuclear Information System (INIS)

Maurya, Savita; Radhakrishna, M.

2015-01-01

Substrate oxide interfaces are of paramount importance in deciding the quality of the semiconductor devices. In this work we have studied how 200 keV proton irradiation affects the interface of a 13 nm thick, atomic layer deposited hafnium dioxide on silicon substrate. Pre- and post-irradiation electrical measurements are used to quantify the effect of proton irradiation for varying electrode geometries. Proton irradiation introduces positive charge in the oxide and at the interface of Si/HfO 2 interface. The gate current is not very much affected under positive injection since the induced positive charge is compensated by the injected electrons. Current voltage characteristics under negative bias get affected by the proton irradiation

Effect of UV irradiation on cutaneous cicatrices

DEFF Research Database (Denmark)

Due, Eva; Rossen, Kristian; Sorensen, Lars Tue

2007-01-01

The aim of this study was to examine the effect of ultraviolet (UV) irradiation on human cutaneous cicatrices. In this randomized, controlled study, dermal punch biopsy wounds served as a wound healing model. Wounds healed by primary or second intention and were randomized to postoperative solar UV...... postoperatively, UV-irradiated cicatrices healing by second intention: (i) were significantly pointed out as the most disfiguring; (ii) obtained significantly higher scores of colour, infiltration and cicatrix area; and (iii) showed significantly higher increase in skin-reflectance measurements of skin......-pigmentation vs. non-irradiated cicatrices. No histological, immunohistochemical or biochemical differences were found. In conclusion, postoperative UV exposure aggravates the clinical appearance of cicatrices in humans....

Effects of hyperthermia and X-irradiation on mouse stromal tissue

NARCIS (Netherlands)

Wondergem, J.; Begg, A. C.; Haveman, J.

1986-01-01

The sensitivity of normal stroma to heat, irradiation and heat combined with irradiation has been studied using the tumour bed effect (TBE) assay. Irradiation before implantation led to a TBE. This TBE was dose dependent below 15 Gy, the TBE remaining relatively constant above 15 Gy. The interval

Renal effects of renal x irradiation and induced autoallergic glomerulonephritis

International Nuclear Information System (INIS)

Rappaport, D.S.; Casarett, G.W.

1979-01-01

This study was conducted to determine what influence a single large x-ray exposure of kidney has on the development and course of an experimental autoallergic glomerulonephritis (EAG) in rats. EAG was induced in female Sprague-Dawley rats by immunization with Bordetella pertussis vaccine and homogenate of homologous kidney tissue and Freund's complete adjuvant. Progressive arteriolonephrosclerosis (ANS) was observed in right (irradiated) kidneys following unilateral renal irradiation (1500 rad). Rats were either immunized, sham-immunized, irradiated, sham-irradiated, or both immunized and irradiated. Light and immunofluorescent microscopic observation, urine protein content, and kidney weights were evaluated. In immunized-irradiated animals the effects of irradiation and immunization were largely additive. Immunization did not considerably influence the development and course of ANS and irradiation did not considerably influence the development and course of EAG

The effect of Gamma-irradiation on the functional properties of starch

International Nuclear Information System (INIS)

BenBettaieb, Nasreddine

2008-01-01

Irradiation is one of the effective methods able to change starch structure and its functional properties. In this research the effect of gamma-irradiation (3, 5, 10, 20 and 50kGy) on the rheological, structural, thermal and morphological properties of corn starch was studied. Viscoamylograph test showed that the maximal consistency of the starch paste and its corresponding temperature decrease with increasing irradiation dose. Textural analysis of paste starch using strain-relaxation test showed the dominance of behaviour elastic after irradiation. Discriminant function analysis (DFA) revealed a good discrimination of the irradiation doses among rheological parameters in the strain-relaxation test. FTIR spectra showed that the irradiated starch displayed a significant decrease in the intensity of the O.H stretch (3000.3600 cm 1 ), C.H stretch (2800.3000 cm 1 ), bending mode of water (1600.1800 cm 1 ) and bending mode of glycosidic linkage (900-950 cm-1). The X-ray diffraction spectra show that did not any modification in the sharp and intensity of peaks after irradiation dose. Differential scanning calorimetry (DSC) of corn starch showed decreases in onset (To), final (Tf) and peak (Tp) gelatinisation temperature with increasing irradiation dose. icrophotographs of polarized light microscopy (LPM) showed that up to 50 kGy irradiation did not present any visible physical effect on the corn starch granule. (Author)

Effect of tumor therapeutic irradiation on the mechanical properties of teeth tissue

Energy Technology Data Exchange (ETDEWEB)

Fraenzel, W. [Dept. of Physics, Martin Luther Univ. Halle (Germany); Gerlach, R. [Univ. Clinic and Policlinic for Radiation Therapy, Martin Luther Univ. Halle (Germany); Hein, H.J. [Univ. Clinic and Policlinic for Orthopaedics and Physical Medicine, Martin Luther Univ. Halle (Germany); Schaller, H.G. [Dept. of Operative Dentistry and Periodontology, Martin Luther Univ. Halle (Germany)

2006-07-01

Tumor irradiation of the head-neck area is accompanied by the development of a so-called radiation caries in the treated patients. In spite of conservative therapeutic measures, the process results in tooth destruction. The present study investigated the effects of irradiation on the demineralization and remineralization of the dental tissue. For this purpose, retained third molars were prepared and assigned either to a test group, which was exposed to fractional irradiation up to 60 Gy, or to a non-irradiated control group. Irradiated and non-irradiated teeth were then demineralized using acidic hydroxyl-cellulose gel; afterwards the teeth were remineralized using either Bifluorid12 {sup registered} or elmex gelee {sup registered}. The nanoindentation technique was used to measure the mechanical properties, hardness and elasticity, of the teeth in each of the conditions. The values were compared to the non-irradiated control group. Irradiation decreased dramatically the mechanical parameters of enamel and dentine. In non-irradiated teeth, demineralization had nearly the same effects of irradiation on the mechanical properties. In irradiated teeth, the effects of demineralization were negligible in comparison to non-irradiated teeth. Remineralization with Bifluorid12 {sup registered} or elmex gelee {sup registered} led to a partial improvement of the mechanical properties of the teeth. The enamel was more positively affected, by remineralization than the dentine. (orig.)

Effect of low fluencies of near-ultraviolet radiation on Bacteroides fragilis survival

International Nuclear Information System (INIS)

Slade, H.J.K.; Jones, D.T.; Woods, D.R.

1982-01-01

Bacteroides fragilis is a convenient obligate anaerobe for an investigation on the effect of near-UV irradiation since the authors have shown that it can be maintained in aerobic solutions for at least 6 h without loss in viability. Furthermore, they recently demonstrated that B. fragilis differs from other bacteria in that it is more sensitive to far-UV (254 nm) radiation in the presence of oxygen. The role of oxygen on near-UV survival in B. fragilis, was investigated. The effect of chloramphenicol was also studied. Survival curves are presented. B. fragilis Bf-2 cells irradiated with increasing fluencies of near-UV light under anaerobic conditions showed no loss in viability. A 'V'-shaped survival curve was obtained when cells were irradiated aerobically. After the initial reduction in viability with fluencies up to 1.5 kJ/m 2 further irradiation resulted in the recovery of colony-forming ability which was maximal at 2.6 kJ/m 2 and remained at this level up to fluencies of 4 kJ/m 2 . (Auth.)

A histopathological effectiveness of pre-operative irradiation for biliary tract cancer

International Nuclear Information System (INIS)

Mizusaki, Kaoru

1993-01-01

There is almost no report on pre-operative irradiation therapy in biliary tract cancer. For the purpose of attaining improved operative results, pre-operative irradiation has so for been performed in our department. We experienced 106 cases of biliary tract cancer during the period from January 1982 to December 1990, including 30 cases treated by pre-operative irradiation. Among 30 cases, 20 cases, including 9 cases of gallbladder cancer and 11 cases of bile duct cancer, were resectable. Final histopathological findings were obtained in 8 cases of gallbladder cancer and 9 cases of bile duct cancer. The effectiveness of irradiation was evaluated according to the histopathological criteria proposed by Ohboshi and Shimosato in 1971. Four cases were Grade I, 2 cases were Grade IIA, and 2 cases were Grade IIB, and 1 case was Grade III of bile duct cancer. In both groups, no correlation was observed between the exposure doses and their effects. Although no correlation was noted between the degree of differentiation of tubular adenocarcinoma of microscopic pathological findings and the irradiation effects, 1 case of poorly differentiated tubular adenocarcinoma of the bile duct was evaluated as Grade III. Mucinous adenocarcinoma and papillary adenocarcinoma of the gallbladder were revealed to be Grade I. According to the main affected site of bile duct cancer, a good irradiation effect was obtained in patients with upper to middle bile duct cancer. The irradiation effect on the gallbladder and the bile duct wall was predominant on the mucous side but less effective on the serous side. From the histopathological findings, the effectiveness of pre-operative irradiation was suggested. These results suggested that the further clinical evaluation, such as rates of resection or prognostic outcome would be relevant. (author)

The effect of gamma-irradiation of Fe2O3 suspension

International Nuclear Information System (INIS)

Adachi, Motoaki; Irie, Setsuko; Kinoshita, Shosaku

1979-01-01

The effect of γ-irradiation on the sedimentation of suspended particles in distilled water has not been satisfactorily considered for disappearance of this effect. Therefore, we investigated the increase in sedimentation by irradiation, it's reappearance and the dependency on the coagulation. The following conclusion became clear; 1) the irradiation against Fe 2 O 3 suspension has the ability to increase the sedimentation velocity of interface and to decrease the turbidity, 2) these phenomena are due to the increase of coagulation induced by irradiation. (author)

Effects of oxygen during γ-irradiation of Micrococcus radiodurans

International Nuclear Information System (INIS)

Myers, D.K.; Johnson, L.D.

1977-01-01

A study has been made of the effects of oxygen on the yield of double strand breaks in the DNA of Micrococcus radiodurans, and of the relation of these effects to cell death. The o.e.r. values for cell survival were considerably smaller than those for the yield of double strand breaks, although they showed similar trends after irradiation in different media. The o.e.r. values for the inhibition of post-irradiation enzymatic repair were similar to those for cell survival. The o.e.r. for radiation-induced breaks in DNA therefore seems to depend on radiochemical reactions that are occurring during irradiation rather than on a preferential enzymatic repair of those strand breaks that are produced by anoxic irradiation. Cell survival depends less on the number of double strand breaks produced than on the ability of the cell to repair the double strand breaks. The maximum yield of double strand breaks after oxic γ-irradiation was approximately 1.7 breaks/krad/10 10 Daltons, corresponding to 1 break per 610 eV. (U.K.)

Effects of oxygen during. gamma. irradiation of Micrococcus radiodurans

Energy Technology Data Exchange (ETDEWEB)

Myers, D K; Johnson, L D [Atomic Energy of Canada Ltd., Chalk River, Ontario. Chalk River Nuclear Labs.

1977-09-01

A study has been made of the effects of oxygen on the yield of double strand breaks in the DNA of Micrococcus radiodurans, and of the relation of these effects to cell death. The OER values for cell survival were considerably smaller than those for the yield of double strand breaks, although they showed similar trends after irradiation in different media. The OER values for the inhibition of post-irradiation enzymatic repair were similar to those for cell survival. The OER for radiation-induced breaks in DNA therefore seems to depend on radiochemical reactions that are occurring during irradiation rather than on a preferential enzymatic repair of those strand breaks that are produced by anoxic irradiation. Cell survival depends less on the number of double strand breaks produced than on the ability of the cell to repair the double strand breaks. The maximum yield of double strand breaks after oxic ..gamma.. irradiation was approximately 1.7 breaks/krad/10/sup 10/Daltons, corresponding to 1 break per 610 eV.

Irradiation Effects on the Decontamination of Microorganisms in Honey

International Nuclear Information System (INIS)

Jo, Cheorun; Kim, Jae Kyung; Kang, Ho Jin; Lee Eun Young; Byun, Myung Woo

2005-09-01

Honey is usually contaminated with numerous microorganisms. Especially, the presence of the spore of Clostridium in honey is dangerous to infants and small children. To determine the effect of a gamma irradiation on the microorganisms in honey, our kinds of honeys (acacia flower, poly floral flower, native A, and native B) were irradiated (0, 5, and 10 kGy) and the total aerobic bacterial count, yeasts and molds, coliform, and Clostridium spp. were detected. In all the honeys, the coliform bacterial, yeast and molds counts were below. The limit of detection (< 101 cfu/g). Total aerobic bacterial and Clostridium spp counts ranged from 85 to 450 cfu/g and 0 to 450 cfu/g in the samples respectively. Acacia and poly floral flower honey were completely sterilized by a 5 kGy irradiation, and both the native honey A and B showed decreased populations of the total aerobic bacteria and Clostridium spp. with a 5 kGy irradiation. Therefore it is concluded that an irradiation treatment could be an effective tool to disinfect honey

Bystander effect of alpha-particle irradiation on mutagenicity and its associated mechanism

International Nuclear Information System (INIS)

Lu Ying; Yang Zhihua; Cao Zhenshan; Fan Feiyue; Zhu Maoxiang

2004-01-01

The work is to investigate α-particle irradiation-induced bystander effects on the mutagenicity in human chromosome 11 in the human-hamster hybrid (A L cells) and its possible mechanism. A L cells were used for assaying mutation rates of human chromosome 11 through screening mutants in the presence of anti-CD59 surface antigen antibody (S1) and complement. A grid was interposed between α-particle source and the cells being irradiated, so as to fix proportion of the irradiated cells (15%) and the bystander effects on the mutagenicity were detected. Free radical scavenger DMSO and intercellular communication inhibitor Lindane were selected to investigate the potential mechanism of α-particle induced bystander effect. There was clear dose-dependent relationship between mutation rate and the dose of alpha particle radiation. However, the mutant fractions of cell population shielded by the grid in α-particle irradiation system were much higher than the expected levels of irradiated cells. Lindane, but not DMSO, could obviously decrease this bystander effect induced by α-particle irradiation. Alpha-particle irradiation can induce bystander effect on the mutagenicity, in which intercellular communication may play important roles

Effects of γ-irradiation on β-pinene content and germination in grapefruit

International Nuclear Information System (INIS)

Uchiyama, Sadao; Kawamura, Yoko; Saito, Yukio; Nagashima, Kimiyo.

1988-01-01

Effects of γ-irradiation on β-pinene content and germination in grapefruit were investigated in order to develop a method to identify γ-irradiated grapefruit. β-Pinene is a component of essential oil in grapefruit and was reported to be susceptible to γ-irradiation. However, it was not degraded by irradiation (30 to 200 krad) in this experiment. When grapefruit irradiated at 50 krad were stored at 10degC for 2 months, no change of β-pinene content was found. β-Pinene itself was also stable to γ-irradiation at 1 Mrad. Thus, identification of irradiated grapefruit from the amount of β-pinene was impossible. On the other hand, the effect of γ-irradiation on radicle elongation was small but that on plumule expansion was so large as to prevent shooting in grapefruit irradiated even at 30 krad. Therefore it should be possible to identify γ-irradiated grapefruit by a germination method. (author)

Effects of ion beam irradiation on Oncidium lanceanum

International Nuclear Information System (INIS)

Zaiton Ahmad; Affrida Abu Hassan; Nurul Aliaa Idris; Mohd Nazir Basiran

2006-01-01

Protocorm-like bodies (PLBs) of an orchid (Oncidium lanceanum) were irradiated using 220 MeV 12 C 5+ ion, accelerated by AVF cyclotron at JAEA, Japan in 2005. Five different doses were applied to the PLBs; 0, 1.0, 2.0, 6.0 and 12.0 Gy. Following irradiation, these PLBs were maintained in cultures for germination and multiplication. Irradiation effects on growth and seedling regeneration patterns as well as morphological characteristics of the in vitro cultures were monitored and recorded. In general, average fresh weights of the irradiated PLBs increased progressively by irradiating the explants at 1.0, 2.0 and reached the maximum at 6.0 Gy. The figure however dropped when the explants were irradiated at 12 Gy. Surprisingly, although the highest average fresh weight was recorded on PLBs irradiated at 6.0 Gy, most of these PLBs were not able to regenerate into complete shoots. On average, only 21 seedlings were successfully regenerated from each gram of these PLBs. The highest shoot regeneration was recorded on cultures irradiated at 2.0 Gy in which 102 seedlings were obtained from one gram of the PLBs. Most of the regenerated seedlings have been transferred to glass house for morphological screening. Molecular analysis showed the presence of DNA polymorphisms among the seedlings from different doses

Some biochemical effects of combined action of external irradiation and strontium 89

International Nuclear Information System (INIS)

Khadzhirusev, S.; Kiradzhiev, G.; Lalova, Kh.

1979-01-01

An attempt was made to assess the influence of strontium 89 on some biochemical effects, induced by external total X-irradiation of the organism in the early terms after treatment. The serum alkaline and acid phosphatase activities and the serum copper and ceruloplasmin content in rats served as indices. Inference is made that in cases, when either of the two radiation actors is alone responsible for obtaining a definite effects, their combination may integrate the biological effect, their combination may integrate the biological effects. Considerations are adduced on the dose span, within which integration of the effect may be expected. The data of this study indicate, that there is integration, when the effective dose external irradiaton effective dose internal irradiation ratio ranks from 1 : 3 to 1 : 1. No integration of effect was found in case when the effective dose of external irradiation eceeds that of internal irradiation. Data are also presented that, in conformity with the parameters studied, the minimal effective radiostrontium dose, generated in the critical organs, is approximately 3 times higher than the minimal effective dose of external irradiation. (author)

Effect of gamma irradiation on the photoluminescence of porous silicon

Energy Technology Data Exchange (ETDEWEB)

Elistratova, M. A., E-mail: Marina.Elistratova@mail.ioffe.ru; Romanov, N. M. [Peter the Great St. Petersburg Polytechnic University (Russian Federation); Goryachev, D. N. [Russian Academy of Sciences, Ioffe Institute (Russian Federation); Zakharova, I. B. [Peter the Great St. Petersburg Polytechnic University (Russian Federation); Sreseli, O. M. [Russian Academy of Sciences, Ioffe Institute (Russian Federation)

2017-04-15

The effect of gamma irradiation on the luminescence properties of porous silicon produced by the electrochemical technique is studied. Changes in the photoluminescence intensity between irradiation doses and over a period of several days after the last irradiation are recorded. The quenching of photoluminescence at low irradiation doses and recovery after further irradiation are registered. It is found that porous silicon is strongly oxidized after gamma irradiation and the oxidation process continues for several days after irradiation. It is conceived that the change in the photoluminescence spectra and intensity of porous silicon after gamma irradiation is caused by a change in the passivation type of the porous surface: instead of hydrogen passivation, more stable oxygen passivation is observed. To stabilize the photoluminescence spectra of porous silicon, the use of fullerenes is proposed. No considerable changes in the photoluminescence spectra during irradiation and up to 18 days after irradiation are detected in a porous silicon sample with a thermally deposited fullerene layer. It is shown that porous silicon samples with a deposited C{sub 60} layer are stable to gamma irradiation and oxidation.

Acute and late effects of 16- and 50-MeV/sub d → Be/ neutrons on the oral mucosa of Rhesus monkeys

International Nuclear Information System (INIS)

Jardine, J.H.; Hussey, D.H.; Boyd, D.D.; Raulston, G.L.; Davidson, T.J.

1975-01-01

Twenty-five rhesus monkeys were randomly assigned to one of five mouth irradiation treatment schedules: control group, no irradiation; 60 Co γ five times weekly; 60 Co twice weekly; 16-MeV/sub d→Be/ neutrons twice weekly. Although the acute reactions of the oral mucosa were similar in the four irradiated groups, the late sequelae were more severe in the animals irradiated twice weekly with 60 Co γ or neutrons. All of the animals irradiated with 60 Co γ twice weekly or with 16 MeV/sub d→Be/ neutrons exhibited oromucosal necrosis, whereas none of those irradiated five times weekly with 60 Co γ did. The difference in the effect of photon fractionation on early and late radiation sequelae may be related to different patterns of redistribution of surviving cells through the division cycle in tissues responsible for early and late damage. (auth)

Irradiation and storage effect on some characteristics of soy seeds

International Nuclear Information System (INIS)

Ramirez Ascheri, Diego Palmiro; Devilla, Ivano Alessandro

2008-01-01

The irradiation has been applied frequently in seeds conservation to obtain reduction of losses caused by physiologic processes, besides reducing the microbial load. However, the irradiation process for X-rays is not a common practice in seeds; for that, it is necessary to study that process, in order to know irradiation effect on the soy seeds quality. The objective of this work was to verify the irradiation effect of X-rays and the storage period on the water, oil and protein contends of soy seeds (Glycine max L.) variety Emgopa 302. The experiment was represented by the combination of two factors: X-rays dosage with four irradiation levels [0, 50, 65 and 70 kV] and storage period in laboratory atmosphere with five levels (0, 15, 30, 45 and 60 days). The water content, oil and protein in seeds were assayed in the beginning and every 15 days of storage. The results showed the seeds quality stayed unaffected in irradiation function in the beginning of the experience, with alterations after 15 days, was verified a quality decreasing with the increasing of the X-rays dosage. The soy seeds irradiated had reduced quality in elapsing of the storage period. (author)

Depth distribution of bubbles in 4He+-ion irradiated nickel and the mechanism of blister formation

International Nuclear Information System (INIS)

Fenske, G.; Das, S.K.; Kaminsky, M.; Miley, G.H.

1978-01-01

While the radiation blistering phenomenon has been widely studied, the mechanism of blister formation is still not well understood. The present studies on depth distribution of helium bubbles in nickel were carried out in order to obtain a better understanding of the radiation blistering process. Particularly, the aim was to understand the experimental observation that the blister skin thickness for many metals irradiated with He + ions of energies lower than 20-keV is a factor of two or more larger than the calculated projected range. (Auth.)

Irradiation as an effective method of food conservation

International Nuclear Information System (INIS)

Stachowicz, W.

1994-01-01

Irradiation as an effective method for food preservation has been introduced. The worldwide history of radiation methods development has been shown. The state of art of international legislation connected with food irradiation and licensing of that technology in different countries has been reviewed. The list of food products commonly accepted for radiation conservation has also been performed

Effects of ion irradiation on the mechanical properties of several polymers

International Nuclear Information System (INIS)

Sasuga, Tsuneo; Kawanishi, Shunichi; Nishi, Masanobu; Seguchi, Tadao

1991-01-01

The effects of high-energy ion irradiation on the tensile properties of polymers were studied under conditions in which ions should pass completely through the specimen and the results were compared with 2 MeV electron irradiation effects. Experiments were carried out on polymers having various constituents and molecular structures, i.e. eight aliphatic polymers and four aromatic polymers. In the aliphatic polymers studied there was scarcely any difference in the dose dependence of the tensile strength and ultimate elongation between proton and electron irradiation. In the aromatic polymers, however, the decrements in the tensile strength and ultimate elongation vs proton dose were less than those for electron irradiation. In heavy-ion irradiation, the radiation damage of PE (an aliphatic polymer) decreased with increase of LET, but no obvious LET effects were observed in PES (an aromatic polymer). (author)

Biological effect of penetration controlled irradiation with ion beams

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Atsushi; Shimizu, Takashi; Kikuchi, Masahiro; Kobayashi, Yasuhiko; Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Yamashita, Takao

1997-03-01

To investigate the effect of local irradiation with ion beams on biological systems, technique for penetration controlled irradiation has been established. The range in a target was controlled by changing the distance from beam window in the atmosphere, and could be controlled linearly up to about 31 {mu}m in biological material. In addition, the effects of the penetration controlled irradiations with 1.5 MeV/u C and He ions were examined using tobacco pollen. The increased frequency of leaky pollen produced by ion beams suggests that the efficient pollen envelope damages would be induced at the range-end of ion beams. (author)

Effects of Si and Ti on the phase stability and swelling behavior of AISI 316 stainless steel

International Nuclear Information System (INIS)

Lee, E.H.; Rowcliffe, A.F.; Kenik, E.A.

1979-01-01

The swelling behavior of neutron irradiated stainless steels is strongly influenced by solute segregation and precipitation phenomena. The extent to which in-reactor swelling behavior may be simulated by heavy ion irradiation depends upon the extent to which in-reactor phase changes are reproduced; this question is addressed by comparing the precipitation behavior under neutron irradiation with behavior during 4 MeV Ni ion irradiation for AISI 316 stainless steel and a related stainless steel containing additions of titanium and silicon. The results are discussed qualitatively in terms of the effects of damage rate on solute segregation and the effects of displacement cascades on the dissolution of particles. It is shown that the partitioning of elements into various phases during irradiation is not a sufficient condition for the iniatiation of swelling in stainless steels modified with silicon and titanium. It is also necessary for helium to be generated simultaneously with the breakdown of the matrix into various phases; it is believed that helium trapping at the growing particle-matrix interface is responsible for the observed physical association between voids and precipitates. (Auth.)

Sanitary effect of gamma irradiation on sewage sludge

International Nuclear Information System (INIS)

Hess, E.; Breer, C.

1975-01-01

Our investigations prove that sludge contains Salmonellae in more than 90% of samples. The maximum number of organisms was 10 7 per litre. One of our most important findings was the fact that neither aerobic stabilization nor anaerobic digestion significantly reduces contamination with Salmonellae. Moreover we found that Salmonellae in sewage sludge spread on grass may survive up to 72 weeks. Fertilizing with unsanitized sludge may therefore lead to transmission from plant to animal. The increasing number of Salmonella carriers among our herds of cattle and their striking accumulation during the grazing period demonstrate that such transmission represents a growing danger. Sanitation of sludge to be used as fertilizer is therefore urgent. In our investigation of the sanitary effect of pasteurization (70degC for 30 min) and of gamma irradiation on sewage sludge, we examined the number of Enterobacteriaceae before and after irradiation in 259 specimens of sludge from 44 different sewage disposal plants. The doses applied were 100, 200, 300, 400 and also 500 krad. We found a linear reduction of Enterobacteriaceae with increasing doses; a dose of 300 krad resulted in a death rate of 10 4 - 10 8 , occasionally 10 9 Enterobacteriaceae; and there were less than 10 Enterobacteriaceae per gram in 97.2% of the samples irradiated with 300 krad. The results of these model experiments could be completely confirmed under practical conditions in the irradiation plant of Geiselbullach. The sanitary effect of gamma irradiation with 300-350 krad, determined by the reduction in Enterobacteriaceae, was equivalent to the effect of heat treatment by pasteurization. (author)

Effects of condition in vitro on the irradiation sensitivity of scales

International Nuclear Information System (INIS)

Zhang Dongxue; Wang Dan; Zhang Zhiwei

2007-01-01

The effects of irradiation and the interactions between irradiation and the ingredients of culture medium and the type of explants on radiation sensitivity of scales of lily were studied. The results showed that when lily scales were exposed to after cultured in vitro for about six days. The survival rate of scales in vitro decreased with the increase of irradiation dose. Irradiation significantly inhibited the sprouting rate and the number of sprouts of scales in vitro. During the bud induction, the effects of ingredients of culture medium on radiation sensitivity of scales were obvious at certain degree, and also the culture time. Both exterior scales and middle scales appeared an identical irradiation sensitivity. (authors)

Effect of bleeding on recovery of erythropoiesis in mice after irradiation

International Nuclear Information System (INIS)

Kubota, Nobuo

1975-01-01

The radioprotective effect of bleeding was studied by depleting 0.4 ml of blood immediately after whole body irradiation. As the indicator in this experiment, 30-day survival rate was used. To analyse the effect of bleeding, erythropoietic recovery after irradiation was examined. Before these experiments, erythropoietic activity after the depletion was examined in non-irradiated mice. Also, radioactive iron uptake was measured in the femur and spleen as an indicator of erythropoietic activity in both irradiated and non-irradiated groups. An increase in the 30-day survival rate was noted: 40% in the group with blood depletion after 700 R irradiation, but only 15% in the group without blood depletion. In blood depleted mice, marked erythropoietic activity was observed in the spleen, but this activity was not increased in the femur bone marrow. Gradual and relatively early increase in iron-59 uptake was observed immediately after irradiation in the blood-depleted mice but not in those with irradiation alone. This phenomenon indicated early recovery of erythropoietic repopulation in the spleen. The mean number of endogenous spleen colonies was 13 and 27 respectively, in the mice without and with blood depletion immediately after 750 R irradiation. (author)

Effect of gamma irradiation on textile waste water

International Nuclear Information System (INIS)

Sarala Selambakkannu; Khomsaton Abu Bakar; Ting Teo Ming; Jamaliah Sharif; Khairul Zaman Dahlan

2011-01-01

This paper studies the use of gamma irradiation for textile waste water treatment. Prior to irradiation, the raw waste water was diluted using tap water to targeted concentration of COD 400 mg/l. The sample was irradiated at selected dose between the ranges of 2 kGy to 100 kGy. The results showed that Irradiation was effective in removing the highly colored refractory organic pollutants. The COD removal at lowest dose, 2 kGy is about 310 mg/l. Meanwhile, at highest dose, 100 kGy the COD reduced to 100 mg/l. The degree of removal influenced by the dose introduced during the treatment process. As the dose increased, higher removal of organic pollutant was recorded. On the other hand, other properties of the wastewater such as pH, turbidity, suspended solid, BOD and color shows tremendous changes as the dose increases. This shows the concentration of pollutants and dose of irradiation applied are directly proportional to each other. (Author)

Effect of gamma irradiation on textile waste water

International Nuclear Information System (INIS)

Selambakkannu, S.; Khomsaton Abu Bakar; Ting, Teo Ming; Jamaliah Sharif; Khairul Zaman Dahlan

2010-01-01

This paper studies the use of gamma irradiation for textile waste water treatment. Prior to irradiation, the raw wastewater was diluted to using tap water to targeted concentration of COD 400 mg/ l. The sample was irradiated at selected dose between the ranges of 2 kGy to 100 kGy. The results showed that Irradiation was effective in removing the highly colored refractory organic pollutants. The degree of removal influenced by the dose introduced during the treatment process. As the dose increased, higher removal of organic pollutant was recorded. The COD removal at lowest dose, 2 kGy is about 310 mg/ l. Meanwhile, at highest dose, 100 kGy the COD reduced to 100 mg/ l. On the other hand, other properties of the wastewater such as pH, turbidity, suspended solid, BOD and color shows tremendous changes as the dose increases. This showed the concentration of pollutants and dose of irradiation applied are directly proportional to each other. (author)

Effect of irradiation on the survival of Salmonella in cooled meat

International Nuclear Information System (INIS)

Szczawinska, M.; Szczawinski, J.; Szulc, M.

1982-01-01

The effect of irradiation by X rays of 1, 2 and 3 kGy on the survival of Salmonella cells in meat during its storage at 0-2 0 C was investigated. The radioresistance of the Salmonella strains as well as the effect of irradiation on the organoleptic properties and shelf-life extension of meat was evaluated. Progressive dying of Salmonella cells which survived the irradiation was recorded during the storage of irradiated meat at 0-2 0 C. After irradiation and storage of meat at 8-10 0 C the number of bacteria decreased within the first days. Then, some of the strains were able to multiply, however after 14 days of storage, especially after irradiation with 3 kGy, the number of Salmonella was always lower than that immediately after irradiation. After the exposure to 3 kGy the shelf-life extension increased at least twice with the organoleptic properties changed insignificantly. (author)

Low dose irradiation effects on DIN 1.4948 mechanical properties

International Nuclear Information System (INIS)

Schaaf, B. van der; Vries, M.I. de

For the SNR 300 the licensing authorities require the determination of the lower boundaries of post-irradiation mechanical properties for DIN 1.4948 parent metal and welded joints. It has been established that with decreasing strain rate the post-irradiation tensile ductility decreases. A transition strain rate has been observed, above which there is no effect of irradiation on ductility. The transition strain rate increases with increasing temperature. Coarse grained heats show lower ultimate tensile strength above 800 K than fine grained heats. There is no significant effect of irradiation on load controlled high cycle fatigue with frequencies of 1 Hz or higher. In low cycle fatigue numbers of cycles to failure decrease with decreasing frequency. Increasing the test temperature reduces the number of cycles to failure even more. The frequency effect is more evident at 823 K. Parent metal has a better fatigue resistance than welded joints in unirradiated and irradiated condition. Creep strength is reduced by irradiation due to loss of ductility. It is shown that with increasing grain size the rupture strength decreases. The ductility of welded joints after irradiation is low, in some cases as low as 0.5% creep strain. After irradiation, tensile, creep and fatigue fracture surfaces show many more intergranular features than in the equivalent unirradiated condition. The promotion of intergranular fracture by irradiation and the consequent degradation of low strain rate mechanical properties is explained by the presence of helium on grain boundaries. Several measures to increase the helium content threshold can be taken, such as grain refinement, homogeneous boron distribution and promotion of helium bubble initiation. In cases where helium embrittlement is encountered, life reduction factors on unirradiated material properties must be applied

Effects of irradiation on the components of implantable pacemakers

International Nuclear Information System (INIS)

Kawamura, Shinji; Ono, Seiji; Kuga, Noriyuki; Shiba, Tooru; Hirose, Tetsuo; Matoba, Masaru

2003-01-01

The purpose of this study was to examine the effects of irradiation on implantable pacemaker components. The pacemaker was divided into three components: lead wire and electrode, battery, and electrical circuit, and each component was irradiated by X-ray and electron beams, respectively. The pacemaker parameters were measured by both telemetry data of the programmer and directly measured data from the output terminal. The following results were obtained. For the lead wire and electrode, there was no effect on the pacemaker function due to irradiation by X-ray and electron beams. In the case of battery irradiation, there was no change in battery voltage or current up to 236 Gy X-ray dose. In the electrical circuit, the pacemaker reverted to the regular beating rate (fixed-rate mode) immediately after the start of X-ray irradiation, and it continued in this mode during irradiation. In patients with their own heartbeat rhythm, changing to the fixed-rate mode may cause dangerous conditions such as ventricular fibrillation. When the accumulated irradiation dose is increased, another failure can be seen in the output voltage of the pacemaker. The pacing output voltage dropped rapidly by about 40% at 30-88 Gy. Decreasing the output voltage results in pacing disorders, and heart failure may occur. In the telemetry data of the programmer, no change in output voltage could be detected, highlighting the difference between telemetry data and actual pacing data. (author)

Decrease of H1 histone and changes in chromatin structure and transcription in pea seedlings after γ-irradiation

International Nuclear Information System (INIS)

Bagi, G.; Hidvegi, E.J.

1983-01-01

Seeds and seedlings of pea have been irradiated between zero to 300 Gy doses of 60 Co gamma-irradiation and examinations were carried out on the chromatin of shoots of 1-week-old etiolated seedlings. There was only a slight change in the gross composition of chromatin after irradiation (in the mass ratios of DNA:RNA:histone:non-histone proteins). Separation of histones, however, showed that after 300 Gy irradiation the quantity of H1 histones decreased by 33% after seed irradiation and 43% after seedling irradiation. The ratio of H1 subfractions also changed. Enzymes DNAase II and micrococcal nuclease digested the chromatin of the irradiated sample 30% faster than the unirradiated one. Transcription kinetics of chromatin showed a gradual decrease of Ksub(m) value on increasing doses of irradiation. There was, however, no difference in the rate of transcription of DNAs, isolated from the chromatin of the control and irradiated samples. Protease and RNAase activity of whole shoots showed enhancement after irradiation. These data suggest that irradiation of either seeds or seedlings results in loosening of the seedling chromatin structure, while there is no change in basic nucleosomal structure. The specific degradation or dissociation of histone H1, localized in the internucleosomal region may be responsible for these changes in the higher order structure of chromatin. This may explain the easier accessibility of chromatin to DNAase II after irradiation and the more tightly bound RNA polymerase, exhibited in decreasing Ksub(m) values. (Auth.)

Effect of irradiated food on life cycle of Trogoderma granarium by gamma irradiations infesting stored barley (Hordum vulgare)

International Nuclear Information System (INIS)

Sisodiya, Manju; Singhvi, P.M.

2012-01-01

To study the effect of irradiated food on the life cycle of Trogoderma granarium crushed barley were irradiated by Gamma irradiations. Fresh eggs were collected from stock culture for getting newly hatched first instar larvae. Twenty, first instar larvae were collected and transferred to the culture tubes containing irradiated food. The larva was observed till the emergence of adults. To calculate the survivality of insects the newly emerged adults were counted daily till the last adult and the emerged beetles were removed. The observation was also made in regard to the time required for adult emergence. The test insect was reared on Gamma irradiated food and survival rate, developmental period and growth index were recorded in different does as 0.1, 0.2, 0.3, 0.4 and 0.5 KGy. The survival rate, developmental period and growth rate of test insect were recorded as 95%, 26.00 and 0.049 respectively at highest dose of 0.5 KGy. Where as 96.67%, 25.33 and 0.051 at lowest dose of 0.1 KGy was recorded. In control condition, they were 98.33%, 29.67 and 0.043 respectively. Irradiation against barley grains had no such effect on the developmental period, survival rate and growth index of Trogoderma granarium. It provides effective alternative to fumigants chemical pesticides which have numerous hazards and create environmental pollution. (author)

Inhibitory Effect of Gamma-Irradiated Chitosan on the Growth of Denitrifiers

Directory of Open Access Journals (Sweden)

Javier Vilcáez

2009-01-01

Full Text Available In order to find an environmentally benign substitute to hazardous inhibitory agents, the inhibitory effect of -irradiated chitosans against a mixed culture of denitrifying bacteria was experimentally evaluated. Unlike other studies using pure aerobic cultures, the observed effect was not a complete inhibition but a transient inhibition reflected by prolonged lag phases and reduced growth rates. Raw chitosan under acid conditions (pH 6.3 exerted the strongest inhibition followed by the 100 kGy and 500 kGy irradiated chitosans, respectively. Therefore, because the molecular weight of chitosan decreases with the degree of -irradiation, the inhibitory properties of chitosan due to its high molecular weight were more relevant than the inhibitory properties gained due to the modification of the surface charge and/or chemical structure by -irradiation. High dosage of -irradiated appeared to increase the growth of mixed denitrifying bacteria in acid pH media. However, in neutral pH media, high dosage of -irradiation appeared to enhance the inhibitory effect of chitosan.

Teratogenic effect of Californium-252 irradiation in rats

International Nuclear Information System (INIS)

Satow, Yukio; Lee, Juing-Yi; Hori, Hiroshi; Okuda, Hiroe; Tsuchimoto, Shigeo; Sawada, Shozo; Yokoro, Kenjiro

1989-01-01

The teratogenicity of Californium-252 (Cf-252) irradiation which generates approximately 70% 2.3 MeV fast neutron and 30% gamma rays was evaluated. A single whole body exposure of Cf-252 at various doses was given to pregnant rats on day 8 or 9 of pregnancy, followed by microscopic autopsy of the fetuses at the terminal stage of pregnancy to search for external and internal malformations. For comparison, pregnant rats were irradiated with various doses of Cobalt-60 (Co-60) standard gamma rays at the same dose rate (1 rad/min.). The doses were 20-120 rad of Cf-252 and 80-220 rad of Co-60. Using frequency of radiation induced malformations observed on day 8 of pregnancy as an index, relative biological effectiveness (RBE) of 2.3-2.7 was obtained from the straight line obtained by modifying by the least squares method the frequency curves of malformed fetuses in total implants and in surviving fetuses. The types of malformations induced by Cf-252 and Co-60 irradiation were alike. Using fetal LD 50 as an index, 2.4 was obtained as RBE when irradiated on day 8 of pregnancy and 3.1 as that when irradiated on day 9. The results showed that Cf-252 had stronger a teratogenic effect than Co-60 gamma rays. (author)

Flux effect on neutron irradiation embrittlement of reactor pressure vessel steels irradiated to high fluences

International Nuclear Information System (INIS)

Soneda, N.; Dohi, K.; Nishida, K.; Nomoto, A.; Iwasaki, M.; Tsuno, S.; Akiyama, T.; Watanabe, S.; Ohta, T.

2011-01-01

Neutron irradiation embrittlement of reactor pressure vessel (RPV) steels is of great concern for the long term operation of light water reactors. In particular, the embrittlement of the RPV steels of pressurized water reactors (PWRs) at very high fluences beyond 6*10 19 n/cm 2 , E > 1 MeV, needs to be understood in more depth because materials irradiated in material test reactors (MTRs) to such high fluences show larger shifts than predicted by current embrittlement correlation equations available worldwide. The primary difference between the irradiation conditions of MTRs and surveillance capsules is the neutron flux. The neutron flux of MTR is typically more than one order of magnitude higher than that of surveillance capsule, but it is not necessarily clear if this difference in neutron flux causes difference in mechanical properties of RPV. In this paper, we perform direct comparison, in terms of mechanical property and microstructure, between the materials irradiated in surveillance capsules and MTRs to clarify the effect of flux at very high fluences and fluxes. We irradiate the archive materials of some of the commercial reactors in Japan in the MTR, LVR-15, of NRI Rez, Czech Republic. Charpy impact test results of the MTR-irradiated materials are compared with the data from surveillance tests. The comparison of the results of microstructural analyses by means of atom probe tomography is also described to demonstrate the similarity / differences in surveillance and MTR-irradiated materials in terms of solute atom behavior. It appears that high Cu material irradiated in a MTR presents larger shifts than those of surveillance data, while low Cu materials present similar embrittlement. The microstructural changes caused by MTR irradiation and surveillance irradiation are clearly different

Solar Irradiance Measurements Using Smart Devices: A Cost-Effective Technique for Estimation of Solar Irradiance for Sustainable Energy Systems

Directory of Open Access Journals (Sweden)

Hussein Al-Taani

2018-02-01

Full Text Available Solar irradiance measurement is a key component in estimating solar irradiation, which is necessary and essential to design sustainable energy systems such as photovoltaic (PV systems. The measurement is typically done with sophisticated devices designed for this purpose. In this paper we propose a smartphone-aided setup to estimate the solar irradiance in a certain location. The setup is accessible, easy to use and cost-effective. The method we propose does not have the accuracy of an irradiance meter of high precision but has the advantage of being readily accessible on any smartphone. It could serve as a quick tool to estimate irradiance measurements in the preliminary stages of PV systems design. Furthermore, it could act as a cost-effective educational tool in sustainable energy courses where understanding solar radiation variations is an important aspect.

Effect of irradiation on the canine exocrine pancreas

International Nuclear Information System (INIS)

Pieroni, P.L.; Rudick, J.; Adler, M.; Nacchiero, M.; Rybak, B.J.

1976-01-01

Effects of irradiation on the pancreas was studied in 6 dogs receiving a dose equivalent to the biologic effect of 4000 R/6 weeks (with a nominal standard dose of 1175 rets) given to patients with Hodgkins disease. After control secretory, histologic and pancreatographic studies, 6 Thomas fistula dogs were subjected to 2400 R tumor dose over two weeks. There was a biphasic response to secretin alone or secretin with cholecystokininpancreozymin. An initial hypersecretion occurred at 2 weeks--volume was increased, but bicarbonate and enzyme output remained unchanged. Thereafter there was a progressive reduction in volume, bicarbonate and enzyme outputs (greater than 90 percent after 3 months). Histology showed early ductal reduplication but with progressive fibrosis, features compatible with chronic pancreatitis. Pancreatic insufficiency may contribute to post-irradiation gastrointestinal symptomatology. Close field irradiation of the pancreas results in actual destruction of the parenchyma

Effect of irradiation and extractive solvents on the Thevetia seed oil ...

African Journals Online (AJOL)

Oil of irradiated thevetia seeds was extracted with different solvents. The effect of irradiation dosages on the extracted oils was studied by comparing the TLC chromatography of irradiated seed oil with that of non-radiated seeds. Saponification values were also compared.

Dietary protein effects on irradiated rat kidney function

International Nuclear Information System (INIS)

Mahler, P.A.; Yatuin, M.B.

1984-01-01

The authors have previously reported that unilaterally nephrectomized, kidney irradiated young male S-D rats have an increased median survival when placed on a low (4%) protein diet, as compared to a normal (20%) or high (50%) protein diet (200, 103, and 59 days respectively for 14 Gy irradiation). They have expanded these studies to examine the effects of irradiation and dietary protein levels on kidney function, by examining the parameters of blood urea nitrogen, serum creatinine, urine urea nitrogen, urine creatinine, urine osmolarity, urine volume, and water consumption. Irradiated 20% protein diet animals show an increase in water consumption and urine production and also a decrease in urine osmolarity, urine urea concentration and urine creatinine concentration. These changes all support the hypothesis the kidney irradiated rats fed a normal protein diet have a reduced capability to concentrate urine compared to nonirradiated control rats. Evaluation of the same parameters in irradiated rats fed a 4% protein diet does not indicate a similar loss of concentrating capability. Whether this protection is due to the growth inhibition of the 4% protein diet or some other phenomena remains to be determined

Study of irradiation effects in austenitic stainless steels

Energy Technology Data Exchange (ETDEWEB)

Etienne, A. [GPM UMR CNRS 6634, Universite et INSA de Rouen (France); Material Department, University of California, Santa Barbara (United States); Pareige, P.; Radiguet, B. [GPM UMR CNRS 6634, Universite et INSA de Rouen (France); Cunningham, N.J.; Odette, G.O. [Material Department, University of California, Santa Barbara (United States); Pokor, C. [EDF RD, departement MMC, site des Renardieres, Moret-sur-Loing (France)

2011-07-01

Chemical analyses using Atom Probe Tomography were performed on a bolt made of cold worked 316 austenitic stainless steel, extracted from the internal structures of a pressurized water reactor after seventeen years of reactor service. The irradiation temperature of these samples was 633 K and the irradiation dose was estimated to 12 dpa. These analyses have shown that neutron irradiation has a strong effect on the intragranular distribution of solute atoms. A very high number density (6.10{sup 23} m{sup -3}) of Ni-Si enriched and Cr-Fe depleted clusters was detected after irradiation. In order to bring complementary experimental results and to determine the mechanism of formation of these Ni-Si nano-clusters, Fe{sup 5+} ion irradiations have been performed on a 316 austenitic stainless steel. As after neutron irradiation, the formation of solute enriched features is observed. Linear features and two kinds of clusters, rounded and torus shaped, are present. Considering that solute enriched features are probably formed by radiation induced segregation on point defect sinks, these different shapes are due to the nature of the sinks where segregation occurs. (authors)

Mutagenicity of 8-methoxypsoralen and long-wave ultraviolet irradiation in V-79 Chinese hamster cells

International Nuclear Information System (INIS)

Burger, P.M.; Simons, J.W.I.M.

1979-01-01

The effect of 8-methoxypsoralen (8-MOP) and long-wave ultraviolet irradiation (UVA) on cell killing and mutation induction was studied in V-79 Chinese hamster cells. No effect was observed after treatment with 8-MOP alone (50 μg/ml, 4 h), UVA alone (9000 J/m 2 ), or 8-MOP metobolized by rat-liver microsomes. Combined treatment with 8-MOP and UVA induced both cell killing and mutation. This was also observed under conditins approaching patient treatment with PUVA photochemotherapy with respect to the concentration of 8-MOP in the skin and the amount of UVA received by the epidermal cells. A simple relation proved to apply for mutation induction under different treatment conditions: 5.5 X 10 -8 per J/m 2 per μg 8-MOP/ml. On this basis the mutation induction in dividing cells per session of PUVA-photochemotherapy amounts to 12.4 X 10 -5 , which is probably an over-estimation. (Auth.)

Effects of ion beam irradiation on Oncidium lanceanum orchids

International Nuclear Information System (INIS)

Zaiton Ahmad; Affrida Abu Hassan

2006-01-01

Protocorm-like bodies (PLBs) of an orchid (Oncidium lanceanum) were irradiated using 220 MeV 12 C 5+ ions, accelerated by AVF cyclotron at JAEA, Japan in 2005. Five different doses were applied to the PLBs; 0, 1.0, 2.0, 6.0 and 12.0 Gy. Following irradiation, these PLBs were maintained in cultures for germination and multiplication. Irradiation effects on growth and seedling regeneration patterns as well as molecular characteristics of the in vitro cultures were monitored and recorded. In general, average fresh weights of the irradiated PLBs increased progressively by irradiating the explants at 1.0, 2.0 and reached the maximum at 6.0 Gy. The figure however dropped when the explants were irradiated at 12 Gy. Surprisingly, although the highest average fresh weight was recorded on PLBs irradiated at 6.0 Gy, most of these PLBs were not able to regenerate into complete shoots. On average, after 4 months of irradiation, only 21 seedlings were successfully regenerated from each gram of these PLBs. The highest shoot regeneration was recorded on cultures irradiated at 2.0 Gy in which 102 seedlings were obtained from one gram of the PLBs. Some morphological changes were seen on in vitro plantlets derived from PLBs irradiated at doses of 1.0 and 2.0 Gy. Most of the regenerated seedlings have been transferred to glasshouse for further morphological selection. Molecular analysis showed the presence of DNA polymorphisms among the seedlings from different doses of irradiation. (Author)

Effect of electron beam irradiation on nutritional ingredient of Tegillarca granosa meat

International Nuclear Information System (INIS)

Li Chao; Yang Wenge; Xu Dalun; Ou Changrong; Shi Huidong

2011-01-01

The influences of 0, 1, 3, 5, 7 and 9 kGy electron beam irradiation on the contents of protein and amino acid and the composition of amino acids and fatty acids in Tegillarca granosa meat were investigated. The results showed that the electron beam had no significant effect on contents of moisture, ash and protein. Fat was sensitive to electron beam irradiation, which decreased with the increasing of irradiation dose. The composition of amino acids remained stable with different doses. The values of EAA/TAA and EAA/NEAA were kept in accordance with FAO/WHO protein model. Besides, electron beam irradiation made no effect on the limiting amino acid (the first and second limiting amino acids were Met + Cys and Val, respectively). The relative content of PUFA increased significantly 1 ∼ 7 kGy irradiation. Electron beam irradiation produced a notable impact on the essential fatty acid, induced the increase of linoleic acid, linolenic acid and arachidonic acid at the doses of 5 ∼ 9 kGy. After the irradiation of 9 kGy, the increments of relative contents of the three essential fatty acids reached 94.61%, 41.37% and 89.91%, respectively. Electron beam irradiation had positive effect on EPA with the doses of 3, 5 and 9 kGy. However, DHA was sensitive to electron beam irradiation, whose relative content decreased with the increasing of irradiation dose and undetected at the dose of 9 kGy. According to the research of decontamination effect, the recommended dose of electron beam irradiation on Tegillarca granosa ws fixed at 3 ∼ 5 kGy. (authors)

Intestinal uptake of bile acids: effect of external abdominal irradiation

International Nuclear Information System (INIS)

Thomson, A.B.R.; Cheeseman, C.I.; Walker, K.

1984-01-01

Abdominal irradiation has recently been shown to influence the uptake of hexoses, amino acids, fatty acids and cholesterol into the jejunum of rats. The present studies were undertaken with a previously validated in vitro technique to determine the effect of abdominal irradiation from a cesium source on the rates of uptake of six bile acids into the jejunum, ileum, and colon. The results show that: 1) there likely are multiple ileal carriers for bile acids: 2) abdominal irradiation has a variable effect on these carriers; 3) the passive permeability to bile acids varies with the bile acid and with the site along the intestine; and 4) abdominal irradiation is associated with a rise in the colonic permeability to only some bile acids

Effects of non-steady irradiation conditions on fusion materials performance

International Nuclear Information System (INIS)

Matsui, H.; Fukumoto, K.; Nagumo, T.; Nita, N.

2001-01-01

During startup of fusion reactors, materials are exposed to neutron irradiation under non-steady temperature condition. Since the temperature of irradiation has decisive effects on the microstructural evolution, the non-steady temperature will have important consequences in the performance of fusion reactor materials. In the present study, a series of vanadium based alloys have been irradiated with neutrons in a temperature cycling condition. It has been found from this study that cavity number density is much greater in temperature cycled specimens than in steady temperature irradiation. Keeping the upper temperature constant, cavity number density is greater for smaller difference between the upper and the lower temperature. It follows that relatively small temperature excursions may have rather significant effects on the fusion material performance in service. (author)

Effect of combination therapy with irradiation and ACNU on rectal cancer in mice

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Masahiko; Nakajima, Atsushi; Kato, Koichiro; Eiraku, Hitoshi (Tokyo Medical Coll. (Japan))

1992-03-01

Colon 26, a transplantable strain of colon cancer, was implanted in BALB/C mice, and the effect of combination therapy with irradiation and ACNU on the mice was studied. Regional irradiation with 9 MeV electron beams was administered once without anesthetization, and ACNU was injected intraperitoneally. The 102 mice used as subjects were divided into 6 groups: nontreated group, 3 Gy irradiation group, 9 Gy irradiation group, 20 mg/kg ACNU group, 40 mg/kg ACNU group, and 3 Gy irradiation + 20 mg/kg ACNU group. Antitumor effects were evaluated based on survival time and inhibition of tumor volume growth, which were calculated from mean days of survival, Kaplan-Meier survival rate curves, and tumor volume growth curves, and the results were compared among these 6 groups. In addition, pathological and cytological studies were performed. As a result, antitumor effect was found to be significantly remarkable in the group receiving the combination of irradiation and ACNU compared to any other group given either irradiation or ACNU alone, suggesting that the antitumor effect of irradiation was potentiated by ACNU. (author).

Irradiation of cells by single and double pulses of high intensity radiation: oxygen sensitization and diffusion kinetics

International Nuclear Information System (INIS)

Epp, E.R.; Ling, C.C.; Weiss, H.

1976-01-01

This paper discusses advances made on both experimental and theoretical approaches involving single and double pulses of high intensity ionizing radiation delivered to cultured bacterial and mammalian cells where the effect of oxygen is concerned. Information gained on the lifetime of oxygen-sensitive species suspected to be produced in critical molecules in irradiated cells and perhaps intimately related to the still unknown mechanisms of oxygen sensitization is described. The diffusion characteristics of oxygen at the cellular level obtained from experimental data are discussed. Current knowledge on intracellular radiolytic oxygen depletion is also presented. Future work on the use of high intensity pulsed radiation as a tool in cellular radiobiological research is outlined. It is expected that obtaining knowledge of the time available for damaged molecules to enter into chemical reactions may lead to insights into the mechanisms of radiation injury in cells, such as those involved in the oxygen effect. (Auth.)