Fine spatiotemporal control of nitric oxide release by infrared pulse-laser irradiation of a photolabile donor.

PubMed

Nakagawa, Hidehiko; Hishikawa, Kazuhiro; Eto, Kei; Ieda, Naoya; Namikawa, Tomotaka; Kamada, Kenji; Suzuki, Takayoshi; Miyata, Naoki; Nabekura, Jun-ichi

2013-11-15

Two-photon-excitation release of nitric oxide (NO) from our recently synthesized photolabile NO donor, Flu-DNB, was confirmed to allow fine spatial and temporal control of NO release at the subcellular level in vitro. We then evaluated in vivo applications. Femtosecond near-infrared pulse laser irradiation of predefined regions of interest in living mouse brain treated with Flu-DNB induced NO-release-dependent, transient vasodilation specifically at the irradiated site. Photoirradiation in the absence of Flu-DNB had no effect. Further, NO release from Flu-DNB by pulse laser irradiation was shown to cause chemoattraction of microglial processes to the irradiated area in living mouse brain. To our knowledge, this is the first demonstration of induction of biological responses in vitro and in vivo by means of precisely controlled, two-photon-mediated release of NO.

THE EFFECT OF X-RAY IRRADIATION ON THE COURSE OF VACCINAL PROCESS CAUSED BY THE ADMINISTRATION OF LIVING BRUCELLOSIS VACCINE TO ANIMALS (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shevtsova, Z.V.

1959-10-01

Investigations were conducted on white rats irradiated at doses of 300 to 600 r and guinea pigs irradiated at doses of 150 to 250 r. It appeared that immunizition with vaccinal brucella culture it the height of radiation sickness increases the death rate of the irradiated animals. As demonstrated by bacteriological examination, development of generalized vaccinal process in the irradiated and immunized animals pursued the same course as in the immunized non- irradiated animals. This procoss was manifested in the dissemination of brucella vaccinal strain in various organs. However the irradiated animals become cleared of the vaccinal culture at amore » somewhat slower rate than in the non-irradiated ones. in guinea pigs, irradiated privious to vaccination there was a slower formation of agglutinins with lower titre than in control non-irradiated animals. Opsonic phagocytic blood index was somewhat lower only in the animals irradiated 24 hours previous to the vaccination. When irradiating white rats 24 hours or 10 days in advance or 24 hours after the vaccination, a delay in the agglutinin production has been observed during the first days following the vaccination. (auth)« less

Dosimetry procedures for an industrial irradiation plant

NASA Astrophysics Data System (ADS)

Grahn, Ch.

Accurate and reliable dosimetry procedures constitute a very important part of process control and quality assurance at a radiation processing plant. γ-Dose measurements were made on the GBS 84 irradiator for food and other products on pallets or in containers. Chemical dosimeters wre exposed in the facility under conditions of the typical plant operation. The choice of the dosimeter systems employed was based on the experience in chemical dosimetry gained over several years. Dose uniformity information was obtained in air, spices, bulbs, feeds, cosmetics, plastics and surgical goods. Most products currently irradiated require dose uniformity which can be efficiently provided by pallet or box irradiators like GBS 84. The radiation performance characteristics and some dosimetry procedures are discussed.

Effects of C3+ ion irradiation on structural, electrical and magnetic properties of Ni nanotubes

NASA Astrophysics Data System (ADS)

Shlimas, D. I.; Kozlovskiy, A. L.; Zdorovets, M. V.; Kadyrzhanov, K. K.; Uglov, V. V.; Kenzhina, I. E.; Shumskaya, E. E.; Kaniukov, E. Y.

2018-03-01

Ion irradiation is an attractive method for obtaining nanostructures that can be used under extreme conditions. Also, it is possible to control the technological process that allows obtaining nanomaterials with new properties at ion irradiation. In this paper, we study the effect of irradiation with 28 MeV C3+ ions and fluences up to 5 × 1011 cm-2 on the structure and properties of template-synthesized nickel nanotubes with a length of 12 μm, with diameters of 400 nm, and a wall thickness of 100 nm. It is demonstrated that the main factor influencing the degradation of nanostructures under irradiation in PET template is the processes of mixing the material of nanostructures with the surrounding polymer. The influence of irradiation with various fluences on the crystal structure, electrical and magnetic properties of nickel nanotubes is studied.

Changes of the antigenic and allergenic properties of a hen's egg albumin in a cake with gamma-irradiated egg white

NASA Astrophysics Data System (ADS)

Lee, Ju.-Woon; Seo, Ji.-Hyun; Kim, Jae.-Hun; Lee, Soo.-Young; Kim, Kwan.-Soo; Byun, Myung.-Woo

2005-04-01

Changes of the antigenicity and allergenicity of a hen's egg albumin (ovalbumin, OVA) in white layer cakes containing egg white gamma-irradiated with 10 or 20 kGy were monitored by an enzyme-linked immunosorbent assay (ELISA), individually formatted with mouse anti-OVA IgG (mouse IgG) and with egg allergic patients' IgE. Mouse IgG recognized OVA in the cakes with irradiated egg white better than that in the control with a non-irradiated one. Whereas, the detected concentrations of intact OVA in the control significantly decreased in the treatments, when determined by IgE-based ELISA. The results appeared to indicate that the antigenicity of the OVA increased, but that the allergenicity was decreased by irradiation and processing. Egg white irradiated for reducing the egg allergy could be used for producing a safer cake from the egg allergy.

Process simulation and dynamic control for marine oily wastewater treatment using UV irradiation.

PubMed

Jing, Liang; Chen, Bing; Zhang, Baiyu; Li, Pu

2015-09-15

UV irradiation and advanced oxidation processes have been recently regarded as promising solutions in removing polycyclic aromatic hydrocarbons (PAHs) from marine oily wastewater. However, such treatment methods are generally not sufficiently understood in terms of reaction mechanisms, process simulation and process control. These deficiencies can drastically hinder their application in shipping and offshore petroleum industries which produce bilge/ballast water and produced water as the main streams of marine oily wastewater. In this study, the factorial design of experiment was carried out to investigate the degradation mechanism of a typical PAH, namely naphthalene, under UV irradiation in seawater. Based on the experimental results, a three-layer feed-forward artificial neural network simulation model was developed to simulate the treatment process and to forecast the removal performance. A simulation-based dynamic mixed integer nonlinear programming (SDMINP) approach was then proposed to intelligently control the treatment process by integrating the developed simulation model, genetic algorithm and multi-stage programming. The applicability and effectiveness of the developed approach were further tested though a case study. The experimental results showed that the influences of fluence rate and temperature on the removal of naphthalene were greater than those of salinity and initial concentration. The developed simulation model could well predict the UV-induced removal process under varying conditions. The case study suggested that the SDMINP approach, with the aid of the multi-stage control strategy, was able to significantly reduce treatment cost when comparing to the traditional single-stage process optimization. The developed approach and its concept/framework have high potential of applicability in other environmental fields where a treatment process is involved and experimentation and modeling are used for process simulation and control. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of an electrochemical process for production of nano-copper oxides: Agglomeration kinetics modeling.

PubMed

Shahcheraghi, Seyed Hadi; Schaffie, Mahin; Ranjbar, Mohammad

2018-06-01

The main objective of this study was the development of a simple, clean, and industrial applicable electrochemical process for production of high pure nano-copper oxides from mining and industrial resources (e.g., ore, spent, slag and wastewater). To conduct the proposed process, a special set up containing an electrochemical cell in an ultrasonic system (28 kHz and 160 W) was proposed. Accordingly, using this set up and applying appropriate voltage (≈ 5 V) at 25 °C, in the presence of N 2 gas, the simultaneous anode dissolution and nano-copper oxides formation (≈ 24 nm) can be occurred, rapidly (less than 45 min). Then, the effect of N 2 gas and free radicals generated by ultrasonic irradiation was studied. The results showed, in the absence of ultrasonic irradiation and N 2 , an increase of electrolyte pH from 6.42 to 10.92, a decrease of electrolyte Eh from 285 mV to -1.14 V, and formation of copper nanoparticles. While, in the presence of ultrasonic and N 2 , the CuO nanoparticles were formed due to presence of H 2 O 2 generated by interaction of free radicals. Moreover, a novel method for kinetics modeling of nanoparticles agglomeration was proposed according to distributed activation energy model and Arrhenius parameters variation. The results showed that, in the absence of ultrasonic irradiation, the nanoparticle agglomerates were firstly formed (interface controlled mechanism) and then, the diffusion of nanoparticle agglomerates was occurred (diffusion controlled mechanism). Therefore, the control of nanoparticles size and shape may be impossible without surfactant. Also, in the presence of ultrasonic irradiation, the whole of agglomeration process followed interface controlled mechanism. Therefore, using ultrasonic irradiation, the nanoparticles shape and size don't change due to prevention of agglomerates diffusion. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of combination treatment of gamma irradiation and ascorbic acid on physicochemical and microbial quality of minimally processed eggplant (Solanum melongena L.)

NASA Astrophysics Data System (ADS)

Hussain, Peerzada R.; Omeera, A.; Suradkar, Prashant P.; Dar, Mohd A.

2014-10-01

Gamma irradiation alone and in combination with ascorbic acid was tested for preventing the surface browning and maintaining the quality attributes of minimally processed eggplant. Eggplant samples after preparation were subjected to treatment of gamma irradiation in the dose range of 0.25-1.0 kGy and to combination treatments of ascorbic acid dip at a concentration of 2.0% w/v and gamma irradiation (dose range 0.5-2.0 kGy) followed by storage at 3±1 °C, RH 80%. Studies revealed inverse correlation (r=-0.93) between the polyphenol oxidase (PPO) activity, browning index and the treatments of ascorbic acid and gamma irradiation. Combinatory treatment of 2.0% w/v ascorbic acid and 1.0 kGy gamma irradiation proved to be significantly (p≤0.05) effective in inhibiting the PPO activity, preventing the surface browning and maintaining the creamy white color and other quality attributes of minimally processed eggplant up to 6 days of refrigerated storage. Sensory evaluation revealed that control and 0.25 kGy irradiated samples were unacceptable only after 3 days of storage. Samples irradiated at 0.5 kGy and 0.75 kGy were unacceptable after 6 days of storage. Microbial analysis revealed that radiation processing of minimally processed eggplant at 1.0 kGy with and without ascorbic acid resulted in around 1 and 1.5 log reduction in yeast and mold count as well as bacterial count just after treatment and 6 days of storage therefore, enhances the microbial safety.

Food preservation using ionizing radiation.

PubMed

Andrews, L S; Ahmedna, M; Grodner, R M; Liuzzo, J A; Murano, P S; Murano, E A; Rao, R M; Shane, S; Wilson, P W

1998-01-01

Irradiation processing has been researched extensively and is now in use worldwide for many food commodities. Irradiation has been successfully used to reduce pathogenic bacteria, eliminate parasites, decrease postharvest sprouting, and extend the shelf life of fresh perishable foods. Although food irradiation is widely accepted in world food markets, U.S. markets have been slower to accept the idea of irradiated food products. For fruits and vegetables, irradiation is not a cure for shelf life problems; cost and quality problems damage preclude its general use. It appears that the most likely use of irradiation in fruits and vegetables is as an insect control in those commodities for which there is no effective alternative method. For grains such as rice and wheat, irradiation has been used primarily to control insect infestation when insects have been shown to develop resistance to the traditional fumigation methods. Treatment of spices with irradiation doses of 10 kGy has proved to extend shelf life without causing significant changes in sensory or chemical quality. Higher doses that effectively sterilize spices, however, may cause undesirable chemical and sensorial changes. For meat, especially red meat, irradiation is considered a viable alternative in the effort to improve the safety of meat products. With time, the authors believe that economic realities and the technical superiority of irradiation for specific poultry products will lead to public acceptance of the process. Irradiation of seafood products is still being considered for approval by the USFDA, although it is currently used in Asian and European markets, especially for shrimp. It is our belief that scientifically based research in food irradiation and the positive results thereof will also prove economical in the twenty-first century. As we move to a more peaceful world with reduced threat of nuclear holocaust, these valid opinions will prevail and will overshadow the distortions and misinformation generated by the opponents of irradiation.

Phenol induced by irradiation does not impair sensory quality of fenugreek and papaya

NASA Astrophysics Data System (ADS)

Chatterjee, Suchandra; Variyar, Prasad S.; Sharma, Arun

2013-11-01

The effect of radiation processing on the sensory quality of fenugreek and papaya exposed to doses in the range of 2.5-10 kGy and 100 Gy-2.5 kGy respectively was investigated. Despite an increase in the content of phenol in the volatile oil of these food products overall sensory quality of the irradiated and control samples was not significantly affected by radiation processing.

Influence of spatiotemporally distributed irradiance data input on temperature evolution in parabolic trough solar field simulations

NASA Astrophysics Data System (ADS)

Bubolz, K.; Schenk, H.; Hirsch, T.

2016-05-01

Concentrating solar field operation is affected by shadowing through cloud movement. For line focusing systems the impact of varying irradiance has been studied before by several authors with simulations of relevant thermodynamics assuming spatially homogeneous irradiance or using artificial test signals. While today's simulation capabilities allow more and more a higher spatiotemporal resolution of plant processes there are only few studies on influence of spatially distributed irradiance due to lack of available data. Based on recent work on generating real irradiance maps with high spatial resolution this paper demonstrates their influence on solar field thermodynamics. For a case study an irradiance time series is chosen. One solar field section with several loops and collecting header is modeled for simulation purpose of parabolic trough collectors and oil as heat transfer medium. Assuming homogeneous mass flow distribution among all loops we observe spatially varying temperature characteristics. They are analysed without and with mass flow control and their impact on solar field control design is discussed. Finally, the potential of distributed irradiance data is outlined.

Irradiation ageing of CSPE/EPR control command electric cables. Correlation between mechanical properties and oxidation

NASA Astrophysics Data System (ADS)

Calmet, J. F.; Carlin, F.; Nguyen, T. M.; Bousquet, S.; Quinot, P.

2002-03-01

In this paper, correlations between the elongation at break and the oxidation of chlorosulfonated polyethylene and ethylene propylene rubber (EPR) polymers in instrumentation and control cables irradiated at different dose rates are brought to evidence. During irradiation, the following phenomena are observed: an increase of oxygen consumption, a degradation of the mechanical properties and a reduction of the oxidation induction time (OIT) measured for EPR. A correlation between the mechanical properties and the OIT of the EPR has only been established in the case of irradiation at low dose rate. This reveals a difference in the oxidative degradation process at low and high dose rates. This study shows the possibility to assess the ageing of electric cables installed inside nuclear power plants by OIT measurements.

The influence of late-stage pupal irradiation and increased irradiated: un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton.

PubMed

Helinski, M E H; Knols, B G J

2009-06-01

Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments with a higher ratio of irradiated versus un-irradiated males were performed. Second, pupae were irradiated just prior to emergence and male mating competitiveness was determined. Males were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. Pupae were irradiated aged 20-26 h (young) as routinely performed, or the pupal stage was artificially prolonged by cooling and pupae were irradiated aged 42-48 h (old). Irradiated males competed at a ratio of 3:1:1 to un-irradiated males for mates in a large cage design. At the 3:1 ratio, the number of females inseminated by males irradiated with 70 Gy as young pupae was similar to the number inseminated by un-irradiated males for the majority of the replicates. At 120 Gy, significantly fewer females were inseminated by irradiated than by un-irradiated males. The irradiation of older pupae did not result in a significantly improved male mating competitiveness compared to the irradiation of young pupae. Our findings indicate that the loss of competitiveness after pupal stage irradiation can be compensated for by a threefold increase of irradiated males, but only for the partially-sterilizing dose. In addition, cooling might be a useful tool to facilitate handling processes of large numbers of mosquitoes in genetic control programmes.

Effects of gamma ray and electron beam irradiation on the mechanical, thermal, structural and physicochemical properties of poly (ether-block-amide) thermoplastic elastomers.

PubMed

Murray, Kieran A; Kennedy, James E; McEvoy, Brian; Vrain, Olivier; Ryan, Damien; Cowman, Richard; Higginbotham, Clement L

2013-01-01

Both gamma ray and electron beam irradiation are widely used as a means of medical device sterilisation. However, it is known that the radiation produced by both processes can lead to undesirable changes within biomedical polymers. The main objective of this research was to conduct a comparative study on the two key radiosterilisation methods (gamma ray and electron beam) in order to identify the more detrimental process in terms of the mechanical, structural, chemical and thermal properties of a common biomedical grade polymer. Poly (ether-block-amide) (PEBA) was prepared by injection moulding ASTM testing specimens and these were exposed to an extensive range of irradiation doses (5-200 kGy) in an air atmosphere. The effect of varying the irradiation dose concentration on the resultant PEBA properties was apparent. For instance, the tensile strength, percentage elongation at break and shore D hardness can be increased/decreased by controlling the aforementioned criteria. In addition, it was observed that the stiffness of the material increased with incremental irradiation doses as anticipated. Melt flow index demonstrated a dramatic increase in the melting strength of the material indicating a sharp increase in molecular weight. Conversely, modulated differential scanning calorimetry established that there were no significant alterations to the thermal transitions. Noteworthy trends were observed for the dynamic frequency sweeps of the material, where the crosslink density increased according to an increase in electron beam irradiation dose. Trans-vinylene unsaturations and the carbonyl group concentration increased with an increment in irradiation dose for both processes when observed by FTIR. The relationship between the irradiation dose rate, mechanical properties and the subsequent surface properties of PEBA material is further elucidated throughout this paper. This study revealed that the gamma irradiation process produced more adverse effects in the PEBA material in contrast to the electron beam irradiation process. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of instant cup noodle, irradiated for immuno-compromised patients

NASA Astrophysics Data System (ADS)

Lee, Ji-Hye; Kim, Jae-Kyung; Park, Jae-Nam; Yoon, Young-Min; Sung, Nak-Yun; Kim, Jae-Hun; Song, Beom-Seok; Yook, Hong-Sun; Kim, Byeong-Keun; Lee, Ju-Woon

2012-08-01

In the present study, initial microbial load of instant cup noodle (ICN) was investigated and gamma irradiation applied to develop immuno-compromised patients food for their safe consumption. The initial microbial population of dried vegetable and meat, and noodle was below the detection limit (1 log CFU/g); however, that of seasoning powder was just above 4 log CFU/g. Moreover, rehydrated-ICN with water at 100 °C still show above 3 log CFU/g of microbial load, which indicates the need for an additional process to control microbial safety of the seasoning powder. The total aerobic bacteria in seasoning powder and rehydrated-ICN could be controlled with 17 kGy gamma irradiation. This result referred 17 kGy gamma irradiation could reach 'practical sterility' of ICN. The overall difference in sensory properties between the non-irradiated and irradiated ICN was insignificant. Thus, gamma irradiation could improve the microbial quality of ICN, and reduce the risk of infection posed by the seasoning powder, without any adverse effects on their sensory quality. These results suggest that gamma-irradiated ICN can be used as a snack food for immuno-compromised patients.

Use of gamma radiation on control of Clostridium botulinum in mortadella formulated with different nitrite levels

NASA Astrophysics Data System (ADS)

Dutra, Monalisa Pereira; Aleixo, Glécia de Cássia; Ramos, Alcinéia de Lemos Souza; Silva, Maurício Henriques Louzada; Pereira, Marcio Tadeu; Piccoli, Roberta Hilsdorf; Ramos, Eduardo Mendes

2016-02-01

This study investigated the effects of applying different doses of gamma radiation (0, 10 and 20 kGy) on Clostridium botulinum spores (107 spores/g) inoculated into mortadellas with different nitrite contents (0, 150 and 300 ppm). We also evaluated the order of application of heat (cooking) and irradiation processing. The products were evaluated for survival of C. botulinum, pH, water activity (Aw), redox potential (Eh) and residual nitrite content. In the non-irradiated raw batters, almost all spores could be recovered when no nitrite was added and only half was recovered with the addition of 150 ppm of nitrite. The use of 150 ppm of nitrite was able to inhibit the germination or growth of C. botulinum in non-irradiated cooked mortadellas after 48 h of processing. However, after 30 days of chilling storage (4 °C), it was possible to recover 105 UFC/g of this microorganism. The gamma irradiation (>10 kGy) had a positive effect on the inactivation of C. botulinum in mortadellas, independent of the sodium nitrite level used and the cooking/irradiation processing order.

Status of food irradiation in the United States

NASA Astrophysics Data System (ADS)

Derr, Donald D.; Engel, Ronald E.

1993-07-01

The time immediately preceding the 8th International Meeting on Radiation Processing in September 1992 has been a landmark period for food irradiation in the United States. U.S. regulatory officials, industry and media representatives, and some consumer organizations share the opinion that radiation processing may be part of the solution to microbiological contamination of products of animal origin. Several new regulations being developed by U.S. regulatory agencies and being petitioned by industry groups are outlined. Renewed interest on the part of the U.S. Army in using irradiated foods in many of their nations is reviewed. The first commercial facility designed for food irradiation and two demonstration food irradiation facilities began operations early in 1992. The progress of these facilities is discussed. The North American Free Trade Agreement (NAFTA) and the Uruguay round of GATT negotiations may significantly lower barriers that impede international agricultural trade. International agreement on appropriate control and inspection procedures would eliminate unnecessary differences and improve mutual trust thus facilitating international trade in irradiated foods. The harmonization of radiation process practices, dosimetry standards, and other issues plays a very important role in meeting the provisions of trade agreeements. It is vitally important to address these issues early in the commercialization of food irradiation throughout the trading world. Some comments in that area are provided. Much has been done already to harmonize regulations and facilitate trade; but there is still much to be done. Regardless of how these issues are resolved, they will have a significant impact on the use of radiation processing for foods and the trade of irradiated foods all over the world.

Effects of irradiation on trans fatty acids formation in ground beef

NASA Astrophysics Data System (ADS)

Brito, Mônica S.; Villavicencio, Anna Lúcia C. H.; Mancini-filho, Jorge

2002-03-01

In order to give the consumer the assurance that meat processed by irradiation is a safe product, a great deal of research has been developed in the world. The effect of irradiation on the hygienic quality of meat and meat products is considered as related to the control of meat-borne parasites of humans; elimination of pathogens from fresh meat and poultry; and elimination of pathogens from processed meat. Lipid oxidation and associated changes are the major causes of the quality deterioration of meat during storage. Irradiation of lipids induces the production of free radicals, which react with oxygen, leading to the formation of carbonyls, responsible for alterations in food nutritional and sensorial characteristics. Trans fatty acids are present in ground beef and can also be formed during its processing. Interestingly, the trans fatty acids, due to their chemical and physical characteristics, show more resistance to the oxidizing process. This property motivated us to investigate the level of the trans fatty acids, as well as the level of oxidation in irradiated ground beef. Irradiation of ground beef was performed by gamma rays from a 60Co source. The applied radiation doses were 0; 1.0; 2.0; 3.0; 4.0; 5.0; 6.0; 7.0 and 8.0 kGy. Lipid peroxidation in terms of TBA number and carbonyl content was monitored during storage. The sample characteristics and trans fatty acids composition were measured, following irradiation and after 60 and 90 days of storage at -10°C.

Electron-Nuclear Quantum Information Processing

DTIC Science & Technology

2008-11-13

quantum information processing that exploits the anisotropic hyperfine coupling. This scheme enables universal control over a 1-electron, N-nuclear spin...exploits the anisotropic hyperfine coupling. This scheme enables universal control over a 1-electron, N-nuclear spin system, addressing only a...sample of irradiated malonic acid. (a) Papers published in peer-reviewed journals (N/A for none) Universal control of nuclear spins via anisotropic

Radiation resistance of non-0157:H7 Shiga Toxin-Producing Escherichia coli suspended in refrigerated catfish fillet meat

USDA-ARS?s Scientific Manuscript database

Ionization (gamma) irradiation is a sustainable and important non-thermal treatment that has been very effective in controlling microorganisms and improving the safety and shelf life of foods. In the design of the food irradiation process, the knowledge of the radiation resistance of the target orga...

Evaluation of microbial loads, physical characteristics, chemical constituents and biological properties of radiation processed Fagonia arabica

NASA Astrophysics Data System (ADS)

Khattak, Khanzadi Fatima

2012-06-01

Whole plant of Fagonia arabica with 3 different particle sizes (30, 50 and 70 mesh) were exposed to gamma radiation doses of 1-10 kGy from a Cobalt 60 source. A series of tests was performed in order to check the feasibility of irradiation processing of the plant. The applied radiation doses did not affect (P<0.05) pH and antimicrobial activities of the plant. The total weight of the dry extracts in methanol as well as water was found increased with irradiation. The irradiated samples showed significant increase in phenolic content and free radical scavenging activity using DPPH. Shortly after irradiation (on the day of radiation treatment) high amounts of free radicals were detected in the irradiated plant samples and the chemiluminescence measurements were generally found to be dose dependent. Maximum luminescence intensity was observed in case of samples with mesh size of 30 for all the radiation doses applied. After a period of one month the chemiluminescence signals of the irradiated samples approximated those of the controls. The study suggests that gamma irradiation treatment is effective for quality improvement and enhances certain beneficial biological properties of the treated materials.

Preliminary study on the effect of x-ray irradiation on Capsicum annum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Subhash, K.; Nizam, J.

The present experiment on Capsicum annum was conducted to study various cytological and genetic effects induced by x-ray irradiation. Dry and soaked seeds were exposed to irradiation by deep x rays at the Radium and Cancer Research Institute, Hyderabad at a dose rate of 99 rads/min. The doses administered were as follows: 3000 rads, 4000 rads, 5000 rads, and 10,000 rads. The cytological preparations were made by following Belling's technique. The irradiated seeds along with the controlled were sown in the soil to observe the morphological variations. The root tip squashes from the irradiated seed material revealed various chromosomal aberrationsmore » such as deletions, parallel bridges, and single and paired fragments of acentric chromosomes, showing cytological irregularities. Bridges were quite common at anaphases. The irradiated seeds were germinated in order to record morphological variations. A period of 150 days seems to be necessary from germination to seed formation; this period is not identical for the irradiated and controlled seeds. In some of the irradiated material the duration was reduced to 120 to 130 days. With this observation it may be presumed that mild doses of radiation have accelerated the germination time and also hastened the growth processes. (auth)« less

Electron beam technology for multipollutant emissions control from heavy fuel oil-fired boiler.

PubMed

Chmielewski, Andrzej G; Ostapczuk, Anna; Licki, Janusz

2010-08-01

The electron beam treatment technology for purification of exhaust gases from the burning of heavy fuel oil (HFO) mazout with sulfur content approximately 3 wt % was tested at the Institute of Nuclear Chemistry and Technology laboratory plant. The parametric study was conducted to determine the sulfur dioxide (SO2), oxides of nitrogen (NO(x)), and polycyclic aromatic hydrocarbon (PAH) removal efficiency as a function of temperature and humidity of irradiated gases, absorbed irradiation dose, and ammonia stoichiometry process parameters. In the test performed under optimal conditions with an irradiation dose of 12.4 kGy, simultaneous removal efficiencies of approximately 98% for SO2, and 80% for NO(x) were recorded. The simultaneous decrease of PAH and one-ringed aromatic hydrocarbon (benzene, toluene, and xylenes [BTX]) concentrations was observed in the irradiated flue gas. Overall removal efficiencies of approximately 42% for PAHs and 86% for BTXs were achieved with an irradiation dose 5.3 kGy. The decomposition ratio of these compounds increased with an increase of absorbed dose. The decrease of PAH and BTX concentrations was followed by the increase of oxygen-containing aromatic hydrocarbon concentrations. The PAH and BTX decomposition process was initialized through the reaction with hydroxyl radicals that formed in the electron beam irradiated flue gas. Their decomposition process is based on similar principles as the primary reaction concerning SO2 and NO(x) removal; that is, free radicals attack organic compound chains or rings, causing volatile organic compound decomposition. Thus, the electron beam flue gas treatment (EBFGT) technology ensures simultaneous removal of acid (SO2 and NO(x)) and organic (PAH and BTX) pollutants from flue gas emitted from burning of HFO. This technology is a multipollutant emission control technology that can be applied for treatment of flue gas emitted from coal-, lignite-, and HFO-fired boilers. Other thermal processes such as metallurgy and municipal waste incinerators are potential candidates for this technology application.

Effect of gamma irradiation on the vitamins, phytochemicals, antimicrobial and antioxidant properties of Ziziphus mauritiana Lam. leaves

NASA Astrophysics Data System (ADS)

Khattak, Khanzadi Fatima; Rahman, Taj Ur

2016-10-01

Plant based food products and medicines are given more consideration for their efficacy, safety and synergistic effects. Radiation processing has been valuably used for microbial decontamination and value addition of the plant materials. The current study is about the effect of gamma irradiation on the quality attributes of Ziziphus mauritiana Lam. leaves. The leaves of the plant were irradiated at the dose levels of 2.5, 5.0, 7.5, 10.0 and 12.5 kGy. The irradiated and control samples were evaluated for vitamin, phytochemicals, antibacterial and DPPH scavenging activities. The results showed that gamma irradiation doses up to 12.5 kGy enhanced the levels of certain phytochemicals and augmented the biological activities.

Shelf life extension of minimally processed cabbage and cucumber through gamma irradiation.

PubMed

Khattak, Amal Badshah; Bibi, Nizakat; Chaudry, Muhammad Ashraf; Khan, Misal; Khan, Maazullah; Qureshi, Muhammad Jamil

2005-01-01

The influence of irradiation of minimally processed cabbage and cucumber on microbial safety, texture, and sensory quality was investigated. Minimally processed, polyethylene-packed, and irradiated cabbage and cucumber were stored at refrigeration temperature (5 degrees C) for 2 weeks. The firmness values ranged from 3.23 kg (control) to 2.82 kg (3.0-kGy irradiated samples) for cucumbers, with a gradual decrease in firmness with increasing radiation dose (0 to 3 kGy). Cucumbers softened just after irradiation with a dose of 3.0 kGy and after 14 days storage, whereas the texture remained within acceptable limits up to a radiation dose of 2.5 kGy. The radiation treatment had no effect on the appearance scores of cabbage; however, scores decreased from 7.0 to 6.7 during storage. The appearance and flavor scores of cucumbers decreased with increasing radiation dose, and overall acceptability was better after radiation doses of 2.5 and 3.0 kGy. The aerobic plate counts per gram for cabbage increased from 3 to 5 log CFU (control), from 1.85 to 2.93 log CFU (2.5 kGy), and from a few colonies to 2.6 log CFU (3.0 kGy) after 14 days of storage at 5 degrees C. A similar trend was noted for cucumber samples. No coliform bacteria were detected at radiation doses greater than 2.0 kGy in either cabbage or cucumber samples. Total fungal counts per gram of sample were within acceptable limits for cucumbers irradiated at 3.0 kGy, and for cabbage no fungi were detected after 2.0-kGy irradiation. The D-values for Escherichia coli in cucumber and cabbage were 0.19 and 0.17 kGy, and those for Salmonella Paratyphi A were 0.25 and 0.29 kGy for cucumber and cabbage, respectively.

Low energy electron beam processing of YBCO thin films

NASA Astrophysics Data System (ADS)

Chromik, Š.; Camerlingo, C.; Sojková, M.; Štrbík, V.; Talacko, M.; Malka, I.; Bar, I.; Bareli, G.; Jung, G.

2017-02-01

Effects of low energy 30 keV electron irradiation of superconducting YBa2Cu3O7-δ thin films have been investigated by means of transport and micro-Raman spectroscopy measurements. The critical temperature and the critical current of 200 nm thick films initially increase with increasing fluency of the electron irradiation, reach the maximum at fluency 3 - 4 × 1020 electrons/cm2, and then decrease with further fluency increase. In much thinner films (75 nm), the critical temperature increases while the critical current decreases after low energy electron irradiation with fluencies below 1020 electrons/cm2. The Raman investigations suggest that critical temperature increase in irradiated films is due to healing of broken Cusbnd O chains that results in increased carrier's concentration in superconducting CuO2 planes. Changes in the critical current are controlled by changes in the density of oxygen vacancies acting as effective pinning centers for flux vortices. The effects of low energy electron irradiation of YBCO turned out to result from a subtle balance of many processes involving oxygen removal, both by thermal activation and kick-off processes, and ordering of chains environment by incident electrons.

[Effect of low-energy 633 nm red light stimulation on proliferation and reactive oxygen species level of human epidermal cell line HaCaT].

PubMed

Chen, Z Y; Li, D L; Duan, X D; Peng, D Z

2016-09-20

To investigate the changes of proliferative activity and reactive oxygen species level of human epidermal cell line HaCaT after being irradiated with low-energy 633 nm red light. Irradiation distance was determined through preliminary experiment. HaCaT cells were conventionally sub-cultured with RPMI 1640 culture medium containing 10% fetal calf serum, 100 U/mL penicillin, and 100 μg/mL streptomycin. Cells of the third passage were used in the following experiments. (1) Cells were divided into blank control group and 0.082, 0.164, 0.245, 0.491, 1.472, 2.453, 4.910, and 9.810 J/cm(2) irradiation groups according to the random number table, with 3 wells in each group. Cells in blank control group were not irradiated, while cells in the latter 8 irradiation groups were irradiated with 633 nm red light for 10, 20, 30, 60, 180, 300, 600, and 1 200 s in turn. Cells were reirradiated once every 8 hours. After being irradiated for 48 hours (6 times) in irradiation groups, the proliferative activity of cells in 9 groups was determined with cell counting kit 8 and microplate reader (denoted as absorbance value). (2) Another batch of cells were grouped and irradiated as in experiment (1). After being irradiated for once in irradiation groups, cells in 9 groups were conventionally cultured for 60 min with detection reagent of reactive oxygen species. At post culture minute (PCM) 0 (immediately), 30, 60, and 120, reactive oxygen species level of cells was determined with microplate reader (denoted as absorbance value). (3) Another batch of cells were divided into blank control group, 0.082, 0.491, 2.453, and 9.810 J/cm(2) irradiation groups, and positive control group. Cells in blank control group and positive control group were not irradiated (positive control reagent of reactive oxygen species was added to cells in positive control group), and cells in irradiation groups were irradiated as in experiment (1) for once. The expression of reactive oxygen species in cells of each group was observed by confocal laser scanning microscope. Data were processed with one-way analysis of variance, analysis of variance for repeated measurement, and t test. (1) Irradiation distance was 10 cm. Proliferative activity of cells in blank control group and 0.082, 0.164, 0.245, 0.491, 1.472, 2.453, 4.910, and 9.810 J/cm(2) irradiation groups was 1.000, 1.116±0.031, 1.146±0.016, 1.162±0.041, 1.179±0.016, 1.207±0.016, 1.247±0.040, 1.097±0.059, and 0.951±0.118, respectively. Compared with that in blank control group, proliferative activity of cells in 0.082-2.453 J/cm(2) irradiation groups was significantly higher (with t values from -22.803 to -6.779, P values below 0.05). Proliferative activity of cells in 4.910 and 9.810 J/cm(2) irradiation groups was similar to that in blank control group (with t values respectively -2.854 and 0.711, P values above 0.05). (2) Compared with that in blank control group, reactive oxygen species level of cells was significantly enhanced at PCM 0 and 30 in 0.164-2.453 J/cm(2) irradiation groups (with t values from -12.453 to -4.684, P<0.05 or P<0.01), while that showed no significant change in 0.082, 4.910, and 9.810 J/cm(2) irradiation groups (with t values from -3.925 to -0.672, P values above 0.05). Compared with that in blank control group, reactive oxygen species level of cells was significantly enhanced at PCM 60 in 0.082-2.453 J/cm(2) irradiation groups (with t values from -11.387 to -4.717, P<0.05 or P<0.01). Compared with that in blank control group, reactive oxygen species level of cells was significantly enhanced at PCM 120 in 0.491-2.453 J/cm(2) irradiation groups (with t values from -10.657 to -6.644, P<0.05 or P<0.01). (3) Compared with that in blank control group, the expression of reactive oxygen species of cells was increased in 0.082, 0.491, and 2.453 J/cm(2) irradiation groups and positive control group. The expression of reactive oxygen species of cells in 9.810 J/cm(2) irradiation group was attenuated when compared with the expressions in the other irradiation groups. Reactive oxygen species expressed in mitochondria of cells in each group. Low-energy 633 nm red light can enhance the proliferation of human epidermal cell line HaCaT, and the effect is closely related to the increase of reactive oxygen species produced by mitochondria after being stimulated by red light irradiation.

Dynamic control of magnetic nanowires by light-induced domain-wall kickoffs

NASA Astrophysics Data System (ADS)

Heintze, Eric; El Hallak, Fadi; Clauß, Conrad; Rettori, Angelo; Pini, Maria Gloria; Totti, Federico; Dressel, Martin; Bogani, Lapo

2013-03-01

Controlling the speed at which systems evolve is a challenge shared by all disciplines, and otherwise unrelated areas use common theoretical frameworks towards this goal. A particularly widespread model is Glauber dynamics, which describes the time evolution of the Ising model and can be applied to any binary system. Here we show, using molecular nanowires under irradiation, that Glauber dynamics can be controlled by a novel domain-wall kickoff mechanism. In contrast to known processes, the kickoff has unambiguous fingerprints, slowing down the spin-flip attempt rate by several orders of magnitude, and following a scaling law. The required irradiance is very low, a substantial improvement over present methods of magneto-optical switching. These results provide a new way to control and study stochastic dynamic processes. Being general for Glauber dynamics, they can be extended to different kinds of magnetic nanowires and to numerous fields, ranging from social evolution to neural networks and chemical reactivity.

Implementation of irradiation of pork for trichina control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Engel, R.E.; Post, A.R.; Post, R.C.

1988-07-01

This article describes the attempts to develop adequate regulatory framework for the use of ionizing radiations in the preservation of food. To be successful, a uniform set of guidelines are needed for the selection, calibration, and application of dosimetry systems; clearance of packaging materials; labeling information; and consumer education programs are essential. The primary regulatory agency that food processors must satisfy is the US FDA. In 1985, in response to an industry petition, the FDA amended its food additive regulations to permit the use of gamma radiation sources to irradiate fresh, non-heat processed pork cuts or carcasses to control Trichinellaspiralis.more » The regulation permits irradiation of only fresh pork within a dose range of 0.3 to 1 kGy.« less

HOMO-AUTOPLASTIC SURGERY IN BURNS OF IRRADIATED ANIMALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khaydarov, A.Kh.; Galayko, S.M.; Levin, S.I.

1962-01-01

Twenty-six rabbits of about the same weight and age were subjected to charring burns on their backs (9 cm/sup 2/) The necrotic scab was removed at regular time intervals and an auto- or homograft was immediately transplanted into the opened wound. Twenty rabbits were subjected to repeated x irradiation (2 x 600 r). Penetrating radiation affected the recipient of the homograft, which, when transplanted during the height of radiation sickness dissolved rapidly. The healing process of autografts was slower in the irradiated animals than in the controls. Homografts transplanted from irradiated animals, 7 days after irradiation with 600 r, tomore » healthy animals, remained alive for a long time and the epithelization of the wound occurred after 4 to 5 weeks. (OTS)« less

Melanin production through novel processing of proopiomelanocortin in the extracellular compartment of the auricular skin of C57BL/6 mice after UV-irradiation.

PubMed

Yamamoto, Hiroyuki; Yamane, Tomohiro; Iguchi, Kazuaki; Tanaka, Kiyotaka; Iddamalgoda, Arunasiri; Unno, Keiko; Hoshino, Minoru; Takeda, Atsushi

2015-09-29

The production of melanin is regulated by α-melanocyte-stimulating hormone (α-MSH), which is produced from proopiomelanocortin (POMC). Keratinocytes release POMC along with lower levels of α-MSH and ACTH. To clarify the mechanism of melanogenesis after ultraviolet (UV)-irradiation, this study focused on the expression of POMC and POMC-derived peptides after UV-irradiation. Western blot analysis and immunoassays indicated that both POMC and α-MSH-like immunoreactivity (α-MSH-LI) increased after UV-irradiation. However, other POMC-derived products were very low. In hypophysectomized mice, α-MSH-LI increased to the same level as in control mice after UV-irradiation. Structural analysis revealed that the major α-MSH-LI product was ACTH(1-8). Furthermore, ACTH(1-8) competed with [(125)I]-α-MSH for receptor binding and increased melanin production via a melanocortin-1 receptor. These results suggested that melanin was produced through ACTH(1-8) after UV-irradiation. Trypsin-like enzymatic activity, which is responsible for POMC activation, increased after UV-irradiation and was identified as tryptase. In mast cell-deficient mice, which do not produce tryptase, α-MSH-LI levels were unchanged after UV-irradiation. The present study demonstrates the production of ACTH(1-8) from POMC by tryptase, which is a novel peptide-processing mechanism in the extracellular compartment of the skin.

Evaluation of the effectiveness of non-irradiated and chlorine-free packaging for fresh beef preservation.

PubMed

Rodrigues, José B M; Sarantópoulos, Claire I G L; Bromberg, Renata; Andrade, Juliana C; Brunelli, Kleber; Miyagusku, Luciana; Marquezini, Miriam G; Yamada, Eunice A

2017-03-01

This study evaluates the potential of using non-irradiated barrier-shrink bags containing ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and ethylene ionomer in their structures to preserve vacuum-packaged fresh beef as an alternative to traditional gamma-ray cross-linked bags containing polyvinylidene chloride (PVDC). Boneless beef rib eye roll cuts were vacuum-packed in an industrial processing plant using EVOH 44% mol, EVOH 32% mol and a control PVDC barrier shrink bags. The cuts were evaluated during storage at 0.5°C. The EVOH films presented similar performance compared to control PVDC barrier shrink bags related to bacteria growth and purge loss. Packages with EVOH 32% mol film presented better performance than control bag with respect to the meat sensorial attributes, including fewer bubbles and better adhesion. EVOH 44% mol bags presented the highest rate of colour loss. The EVOH 32% mol non-irradiated and chlorine-free film is as effective for the preservation of fresh beef as traditional PVDC-irradiated shrink bags. Copyright © 2016 Elsevier Ltd. All rights reserved.

Surface patterning of multilayer graphene by ultraviolet laser irradiation in biomolecule sensing devices

NASA Astrophysics Data System (ADS)

Chang, Tien-Li; Chen, Zhao-Chi

2015-12-01

The study presents a direct process for surface patterning of multilayer graphene on the glass substrate as a biosensing device. In contrast to lithography with etching, the proposed process provides simultaneous surface patterning of multilayer graphene through nanosecond laser irradiation. In this study, the multilayer graphene was prepared by a screen printing process. Additionally, the wavelength of the laser beam was 355 nm. To perform the effective laser process with the small heat affected zone, the surface patterns on the sensing devices could be directly fabricated using the laser with optimal control of the pulse overlap at a fluence threshold of 0.63 J/cm2. The unique patterning of the laser-ablated surface exhibits their electrical and hydrophilic characteristics. The hydrophilic surface of graphene-based sensing devices was achieved in the process with the pulse overlap of 90%. Furthermore, the sensing devices for controlling the electrical response of glucose by using glucose oxidase can be used in sensors in commercial medical applications.

Physical-chemical analyses of irradiated papayas ( Carica papaya L.)

NASA Astrophysics Data System (ADS)

Camargo, R. J.; Tadini, C. C.; Sabato, S. F.

2007-11-01

Papaya is cultivated in Espírito Santo State/Brazil and as it stands up to irradiation, it is important to validate this technology, since it is already being applied in some countries. Penetration energy, ratio (relation between soluble solids and titrable acidity) and skin color were evaluated to verify the influence of four different doses of irradiation (0.0, 0.5, 0.75 and 1.00 kGy) on papayas, during 21 days. As a result for the skin color and the penetration energy, it was found that in the first days after irradiation, these variables increased with increase in radiation dose; however, after a time lapse, the tendency inverted and the irradiated fruits had a slower ripening process. For the ratio, a very important variable that it is responsible for the fruit taste, no difference was found between irradiated and the control fruit. Color and texture measurements are dependent on the storage temperature.

Backscattering measuring system for optimization of intravenous laser irradiation dose

NASA Astrophysics Data System (ADS)

Rusina, Tatyana V.; Popov, V. D.; Melnik, Ivan S.; Dets, Sergiy M.

1996-11-01

Intravenous laser blood irradiation as an effective method of biostimulation and physiotherapy becomes a more popular procedure. Optimal irradiation conditions for each patient are needed to be established individually. A fiber optics feedback system combined with conventional intravenous laser irradiation system was developed to control of irradiation process. The system consists of He-Ne laser, fiber optics probe and signal analyzer. Intravenous blood irradiation was performed in 7 healthy volunteers and 19 patients with different diseases. Measurements in vivo were related to in vitro blood irradiation which was performed in the same conditions with force-circulated venous blood. Comparison of temporal variations of backscattered light during all irradiation procedures has shown a strong discrepancy on optical properties of blood in patients with various health disorders since second procedure. The best cure effect was achieved when intensity of backscattered light was constant during at least five minutes. As a result, the optical irradiation does was considered to be equal 20 minutes' exposure of 3 mW He-Ne laser light at the end of fourth procedure.

Optimal control of multiphoton ionization dynamics of small alkali aggregates

NASA Astrophysics Data System (ADS)

Lindinger, A.; Bartelt, A.; Lupulescu, C.; Vajda, S.; Woste, Ludger

2003-11-01

We have performed transient multi-photon ionization experiments on small alkali clusters of different size in order to probe their wave packet dynamics, structural reorientations, charge transfers and dissociative events in different vibrationally excited electronic states including their ground state. The observed processes were highly dependent on the irradiated pulse parameters like wavelength range or its phase and amplitude; an emphasis to employ a feedback control system for generating the optimum pulse shapes. Their spectral and temporal behavior reflects interesting properties about the investigated system and the irradiated photo-chemical process. First, we present the vibrational dynamics of bound electronically excited states of alkali dimers and trimers. The scheme for observing the wave packet dynamics in the electronic ground state using stimulated Raman-pumping is shown. Since the employed pulse parameters significantly influence the efficiency of the irradiated dynamic pathways photo-induced ioniziation experiments were carried out. The controllability of 3-photon ionization pathways is investigated on the model-like systems NaK and K2. A closed learning loop for adaptive feedback control is used to find the optimal fs pulse shape. Sinusoidal parameterizations of the spectral phase modulation are investigated in regard to the obtained optimal field. By reducing the number of parameters and thereby the complexity of the phase moduation, optimal pulse shapes can be generated that carry fingerprints of the molecule's dynamical properties. This enables to find "understandable" optimal pulse forms and offers the possiblity to gain insight into the photo-induced control process. Characteristic motions of the involved wave packets are proposed to explain the optimized dynamic dissociation pathways.

The influence of radiation-induced vacancy on the formation of thin-film of compound layer during a reactive diffusion process

NASA Astrophysics Data System (ADS)

Akintunde, S. O.; Selyshchev, P. A.

2016-05-01

A theoretical approach is developed that describes the formation of a thin-film of AB-compound layer under the influence of radiation-induced vacancy. The AB-compound layer is formed as a result of a chemical reaction between the atomic species of A and B immiscible layers. The two layers are irradiated with a beam of energetic particles and this process leads to several vacant lattice sites creation in both layers due to the displacement of lattice atoms by irradiating particles. A- and B-atoms diffuse via these lattice sites by means of a vacancy mechanism in considerable amount to reaction interfaces A/AB and AB/B. The reaction interfaces increase in thickness as a result of chemical transformation between the diffusing species and surface atoms (near both layers). The compound layer formation occurs in two stages. The first stage begins as an interfacial reaction controlled process, and the second as a diffusion controlled process. The critical thickness and time are determined at a transition point between the two stages. The influence of radiation-induced vacancy on layer thickness, speed of growth, and reaction rate is investigated under irradiation within the framework of the model presented here. The result obtained shows that the layer thickness, speed of growth, and reaction rate increase strongly as the defect generation rate rises in the irradiated layers. It also shows the feasibility of producing a compound layer (especially in near-noble metal silicide considered in this study) at a temperature below their normal formation temperature under the influence of radiation.

Precipitate resolution in an electron irradiated ni-si alloy

NASA Astrophysics Data System (ADS)

Watanabe, H.; Muroga, T.; Yoshida, N.; Kitajima, K.

1988-09-01

Precipitate resolution processes in a Ni-12.6 at% Si alloy under electron irradiation have been observed by means of HVEM. Above 400°C, growth and resolution of Ni 3Si precipitates were observed simultaneously. The detail stereoscopic observation showed that the precipitates close to free surfaces grew, while those in the middle of a specimen dissolved. The critical dose when the precipitates start to shrink increases with increasing the depth. This depth dependence of the precipitate behavior under irradiation has a close relation with the formation of surface precipitates and the growth of solute depleted zone beneath them. The temperature and dose dependence of the resolution rate showed that the precipitates in the solute depleted zone dissolved by the interface controlled process of radiation-enhanced diffusion.

Effect of the gamma radiation dose rate on psychrotrophic bacteria, thiobarbituric acid reactive substances, and sensory characteristics of mechanically deboned chicken meat.

PubMed

Brito, Poliana P; Azevedo, Heliana; Cipolli, Kátia M V A B; Fukuma, Henrique T; Mourão, Gerson B; Roque, Cláudio V; Miya, Norma T; Pereira, José L

2011-03-01

Frozen samples of mechanically deboned chicken meat (MDCM) with skin were irradiated with gamma radiation doses of 0.0 kGy (control) and 3 kGy at 2 different radiation dose rates: 0.32 kGy/h (3 kGy) and 4.04 kGy/h (3 kGy). Batches of irradiated and control samples were evaluated during 11 d of refrigerated (2 ± 1 °C) storage for the following parameters: total psychrotrophic bacteria count, thiobarbituric acid reactive substances (TBARS), evaluation of objective color (L*, a*, and b*) and a sensory evaluation (irradiated odor, oxidized odor, pink and brown colors). No statistical difference (P > 0.05) was found amongst the TBARS values obtained for the MDCM samples irradiated with dose rates of 0.32 and 4.04 kGy/h. There was a significant increase (P < 0.05) in the psychrotrophic bacterial count as from the 7th day of refrigerated storage, for the MDCM samples irradiated at the dose rate of 4.04 kGy/h. With respect to the attribute of oxidized odor, the samples irradiated with a dose rate of 0.32 kGy/h showed a stronger intensity and were significantly different (P < 0.05) from the sample irradiated with a dose rate of 4.04 kGy/h on days 0 and 2 of refrigerated storage. Irradiation with a dose rate of 4.04 kGy/h (3 kGy) was shown to be the best condition for the processing of MDCM according to the evaluation of all the variables, under the conditions of this study. Practical Application:  The results obtained for the application of different dose rates of ionizing radiation to mechanically deboned chicken meat will provide the food industry with information concerning the definition of the best processing conditions to maximize the sensory and food quality.

Commercial implementation of food irradiation

NASA Astrophysics Data System (ADS)

Welt, M. A.

In July 1981, the first specifically designed multi-purpose irradiation facility for food irradiation was put into service by the Radiation Technology, Inc. subsidiary Process Technology, Inc. in West Memphis, Arkansas. The operational experience gained, resulted in an enhanced design which was put into commercial service in Haw River, North Carolina, by another subsidiary, Process Technology (N.C.), Inc. in October 1983. These facilities have enabled the food industry to assess the commercial viability of food irradiation. Further impetus towards commercialization of food irradiation was gained in March 1981 with the filing in the Federal Register, by the FDA, of an Advanced Proposed Notice of Rulemaking for Food Irradiation. Two years later in July 1983, the FDA approved the first food additive regulation involving food irradiation in nineteen years, when they approved the Radiation Technology, Inc. petition calling for the sanitization of spices, onion powder and garlic powder at a maximum dosage of 10 kGy. Since obtaining the spice irradiation approval, the FDA has accepted four additional petitions for filing in the Federal Register. One of the petitions which extended spice irradiation to include insect disinfestation has issued into a regulation while the remaining petitions covering the sanitization of herbs, spice blends, vegetable seasonings and dry powdery enzymes as well as the petition to irradiate hog carcasses and pork products for trichinae control at 1 kGy, are expected to issue either before the end of 1984 or early in 1985. More recently, food irradiation advocates in the United States received another vote of confidence by the announcement that a joint venture food irradiation facility to be constructed in Hawaii by Radiation Technology, is backed by a contractual committment for the processing of 40 million pounds of produce per year. Another step was taken when the Port of Salem, New Jersey announced that the Radiation Technology Model RT-4104-4048(TM) irradiation facility was chosen to interface with the only East Coast grain elevator in the United States. These factors, along with concern over the ban of EDB as a post harvest fumigant, coupled with the expected FDA action to approve the use of irradiation for the insect disinfestation of fruit and vegetables, should finally permit the commercial implementation of food irradiation to take hold in the United States.

Reconstruction of solar spectral irradiance since the Maunder minimum

NASA Astrophysics Data System (ADS)

Krivova, N. A.; Vieira, L. E. A.; Solanki, S. K.

2010-12-01

Solar irradiance is the main external driver of the Earth's climate. Whereas the total solar irradiance is the main source of energy input into the climate system, solar UV irradiance exerts control over chemical and physical processes in the Earth's upper atmosphere. The time series of accurate irradiance measurements are, however, relatively short and limit the assessment of the solar contribution to the climate change. Here we reconstruct solar total and spectral irradiance in the range 115-160,000 nm since 1610. The evolution of the solar photospheric magnetic flux, which is a central input to the model, is appraised from the historical record of the sunspot number using a simple but consistent physical model. The model predicts an increase of 1.25 W/m2, or about 0.09%, in the 11-year averaged solar total irradiance since the Maunder minimum. Also, irradiance in individual spectral intervals has generally increased during the past four centuries, the magnitude of the trend being higher toward shorter wavelengths. In particular, the 11-year averaged Ly-α irradiance has increased by almost 50%. An exception is the spectral interval between about 1500 and 2500 nm, where irradiance has slightly decreased (by about 0.02%).

Oxidative decomposition of aromatic hydrocarbons by electron beam irradiation

NASA Astrophysics Data System (ADS)

Han, Do-Hung; Stuchinskaya, Tatiana; Won, Yang-Soo; Park, Wan-Sik; Lim, Jae-Kyong

2003-05-01

Decomposition of aromatic volatile organic compounds (VOCs) under electron beam irradiation was studied in order to examine the kinetics of the process, to characterize the reaction product distribution and to develop a process of waste gas control technology. Toluene, ethylbenzene, o-, m-, p-xylenes and chlorobenzene were used as target materials. The experiments were carried out at doses ranging from 0.5 to 10 kGy, using a flow reactor utilized under electron beam irradiation. Maximum degrees of decomposition carried out at 10 kGy in air environment were 55-65% for “non-chlorinated” aromatic VOC and 85% for chlorobenzene. It was found that a combination of aromatic pollutants with chlorobenzene would considerably increase the degradation value up to nearly 50% compared to the same compounds in the absence of chlorine groups. Based on our experimental observation, the degradation mechanism of the aromatic compounds combined with chloro-compound suggests that a chlorine radical, formed from EB irradiation, induces a chain reaction, resulting in an accelerating oxidative destruction of aromatic VOCs.

Apparatus for decoupled thermo-photocatalytic pollution control

DOEpatents

Tabatabaie-Raissi, Ali; Muradov, Nazim Z.; Martin, Eric

2003-04-22

A new method for design and scale-up of photocatalytic and thermocatalytic processes is disclosed. The method is based on optimizing photoprocess energetics by decoupling of the process energy efficiency from the DRE for target contaminants. The technique is applicable to photo-thermocatalytic reactor design and scale-up. At low irradiance levels, the method is based on the implementation of low pressure drop biopolymeric and synthetic polymeric support for titanium dioxide and other band-gap media. At high irradiance levels, the method utilizes multifunctional metal oxide aerogels and other media within a novel rotating fluidized particle bed reactor.

Experimental validation of a numerical model predicting the charging characteristics of Teflon and Kapton under electron beam irradiation

NASA Technical Reports Server (NTRS)

Hazelton, R. C.; Yadlowsky, E. J.; Churchill, R. J.; Parker, L. W.; Sellers, B.

1981-01-01

The effect differential charging of spacecraft thermal control surfaces is assessed by studying the dynamics of the charging process. A program to experimentally validate a computer model of the charging process was established. Time resolved measurements of the surface potential were obtained for samples of Kapton and Teflon irradiated with a monoenergetic electron beam. Results indicate that the computer model and experimental measurements agree well and that for Teflon, secondary emission is the governing factor. Experimental data indicate that bulk conductivities play a significant role in the charging of Kapton.

[Soft- and hardware support for the setup for computer tracking of radiation teletherapy].

PubMed

Tarutin, I G; Piliavets, V I; Strakh, A G; Minenko, V F; Golubovskiĭ, A I

1983-06-01

A hard and soft ware computer assisted complex has been worked out for gamma-beam therapy. The complex included all radiotherapeutic units, including a Siemens program controlled betatron with an energy of 42 MEV computer ES-1022, a Medigraf system of the processing of graphic information, a Mars-256 system for control over the homogeneity of distribution of dose rate on the field of irradiation and a package of mathematical programs to select a plan of irradiation of various tumor sites. The prospects of the utilization of such complexes in the dosimetric support of radiation therapy are discussed.

Irradiation Effects in Fosterrite and the Nature of Interstellar Grains: A Coordinated Spectroscopy and Electron Microscopy Study

NASA Technical Reports Server (NTRS)

Keller, Lindsay P.; Christoffersen, R.

2007-01-01

Crystalline and amorphous silicates condense in the outflows of low mass evolved stars and massive red supergiant stars and are injected into the interstellar medium (ISM) where they are rendered almost completely amorphous by a multitude of destructive processes (e.g. shock, grain-grain collisions, and irradiation). Irradiation effects in particular may have played an important role in the genesis and modification of primitive grains in cometary dust, but unraveling those effects requires controlled experiments under appropriate conditions and with an emphasis on materials relevant to the ISM. Here we report our infrared (IR) microspectroscopy and trans-mission electron microscope (TEM) measurements on forsterite that was amorphized through irradiation by high energy heavy ions.

Controlled release of tyrosol and ferulic acid encapsulated in chitosan-gelatin films after electron beam irradiation

NASA Astrophysics Data System (ADS)

Benbettaïeb, Nasreddine; Assifaoui, Ali; Karbowiak, Thomas; Debeaufort, Frédéric; Chambin, Odile

2016-01-01

This work deals with the study of the release kinetics of antioxidants (ferulic acid and tyrosol) incorporated into chitosan-gelatin edible films after irradiation processes. The aim was to determine the influence of electron beam irradiation (at 60 kGy) on the retention of antioxidants in the film, their release in water (pH=7) at 25 °C, in relation with the barrier and mechanical properties of biopolymer films. The film preparation process coupled to the irradiation induced a loss of about 20% of tyrosol but did not affect the ferulic acid content. However, 27% of the ferulic acid remained entrapped in the biopolymer network during the release experiments whereas all tyrosol was released. Irradiation induced a reduction of the release rate for both compounds, revealing that cross-linking occurred during irradiation. This was confirmed by the mechanical properties enhancement which tensile strength value significantly increased and by the reduction of permeabilities. Although molecular weights, molar volume and molecular radius of the two compounds are very similar, the effective diffusivity of tyrosol was 40 times greater than that of ferulic acid. The much lower effective diffusion coefficient of ferulic acid as determined from the release kinetics was explained by the interactions settled between ferulic acid molecules and the gelatin-chitosan matrix. As expected, the electron beam irradiation allowed modulating the retention and then the release of antioxidants encapsulated.

Patterning and reduction of graphene oxide using femtosecond-laser irradiation

NASA Astrophysics Data System (ADS)

Kang, SeungYeon; Evans, Christopher C.; Shukla, Shobha; Reshef, Orad; Mazur, Eric

2018-07-01

Graphene has emerged as one of the most versatile materials ever discovered due to its extraordinary electronic, optical, thermal, and mechanical properties. However, device fabrication is a well-known challenge and requires novel fabrication methods to realize the complex integration of graphene-based devices. Here, we demonstrate direct laser writing of reduced graphene oxide using femtosecond-laser irradiation at λ = 795 nm. We perform a systematic study of the reduction process of graphene oxide to graphene by varying both the laser fluence and the pulse repetition rate. Our observations show that the reduction has both thermal and non-thermal features, and suggest that we can achieve better resolution and conductivity using kHz pulse trains than using MHz pulse trains or a continuous wave laser. Our reduced graphene oxide lines written at 10-kHz exhibit a 5 order-of-magnitude decrease in resistivity compared to a non-irradiated control sample. This study provides new insight into the reduction process of graphene oxide and opens doors to achieving a high degree of flexibility and control in the fabrication of graphene layers.

Temperature dependence on plasma-induced damage and chemical reactions in GaN etching processes using chlorine plasma

NASA Astrophysics Data System (ADS)

Liu, Zecheng; Ishikawa, Kenji; Imamura, Masato; Tsutsumi, Takayoshi; Kondo, Hiroki; Oda, Osamu; Sekine, Makoto; Hori, Masaru

2018-06-01

Plasma-induced damage (PID) on GaN was optimally reduced by high-temperature chlorine plasma etching. Energetic ion bombardments primarily induced PID involving stoichiometry, surface roughness, and photoluminescence (PL) degradation. Chemical reactions under ultraviolet (UV) irradiation and chlorine radical exposure at temperatures higher than 400 °C can be controlled by taking into account the synergism of simultaneous photon and radical irradiations to effectively reduce PID.

LabVIEW-based control software for para-hydrogen induced polarization instrumentation.

PubMed

Agraz, Jose; Grunfeld, Alexander; Li, Debiao; Cunningham, Karl; Willey, Cindy; Pozos, Robert; Wagner, Shawn

2014-04-01

The elucidation of cell metabolic mechanisms is the modern underpinning of the diagnosis, treatment, and in some cases the prevention of disease. Para-Hydrogen induced polarization (PHIP) enhances magnetic resonance imaging (MRI) signals over 10,000 fold, allowing for the MRI of cell metabolic mechanisms. This signal enhancement is the result of hyperpolarizing endogenous substances used as contrast agents during imaging. PHIP instrumentation hyperpolarizes Carbon-13 ((13)C) based substances using a process requiring control of a number of factors: chemical reaction timing, gas flow, monitoring of a static magnetic field (Bo), radio frequency (RF) irradiation timing, reaction temperature, and gas pressures. Current PHIP instruments manually control the hyperpolarization process resulting in the lack of the precise control of factors listed above, resulting in non-reproducible results. We discuss the design and implementation of a LabVIEW based computer program that automatically and precisely controls the delivery and manipulation of gases and samples, monitoring gas pressures, environmental temperature, and RF sample irradiation. We show that the automated control over the hyperpolarization process results in the hyperpolarization of hydroxyethylpropionate. The implementation of this software provides the fast prototyping of PHIP instrumentation for the evaluation of a myriad of (13)C based endogenous contrast agents used in molecular imaging.

LabVIEW-based control software for para-hydrogen induced polarization instrumentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agraz, Jose, E-mail: joseagraz@ucla.edu; Grunfeld, Alexander; Li, Debiao

2014-04-15

The elucidation of cell metabolic mechanisms is the modern underpinning of the diagnosis, treatment, and in some cases the prevention of disease. Para-Hydrogen induced polarization (PHIP) enhances magnetic resonance imaging (MRI) signals over 10 000 fold, allowing for the MRI of cell metabolic mechanisms. This signal enhancement is the result of hyperpolarizing endogenous substances used as contrast agents during imaging. PHIP instrumentation hyperpolarizes Carbon-13 ({sup 13}C) based substances using a process requiring control of a number of factors: chemical reaction timing, gas flow, monitoring of a static magnetic field (B{sub o}), radio frequency (RF) irradiation timing, reaction temperature, and gas pressures.more » Current PHIP instruments manually control the hyperpolarization process resulting in the lack of the precise control of factors listed above, resulting in non-reproducible results. We discuss the design and implementation of a LabVIEW based computer program that automatically and precisely controls the delivery and manipulation of gases and samples, monitoring gas pressures, environmental temperature, and RF sample irradiation. We show that the automated control over the hyperpolarization process results in the hyperpolarization of hydroxyethylpropionate. The implementation of this software provides the fast prototyping of PHIP instrumentation for the evaluation of a myriad of {sup 13}C based endogenous contrast agents used in molecular imaging.« less

Mammalian Target of Rapamycin Inhibition With Rapamycin Mitigates Radiation-Induced Pulmonary Fibrosis in a Murine Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chung, Eun Joo; Sowers, Anastasia; Thetford, Angela

Purpose: Radiation-induced pulmonary fibrosis (RIPF) is a late toxicity of therapeutic radiation. Signaling of the mammalian target of rapamycin drives several processes implicated in RIPF, including inflammatory cytokine production, fibroblast proliferation, and epithelial senescence. We sought to determine if mammalian target of rapamycin inhibition with rapamycin would mitigate RIPF. Methods and Materials: C57BL/6NCr mice received a diet formulated with rapamycin (14 mg/kg food) or a control diet 2 days before and continuing for 16 weeks after exposure to 5 daily fractions of 6 Gy of thoracic irradiation. Fibrosis was assessed with Masson trichrome staining and hydroxyproline assay. Cytokine expression was evaluated by quantitative real-timemore » polymerase chain reaction. Senescence was assessed by staining for β-galactosidase activity. Results: Administration of rapamycin extended the median survival of irradiated mice compared with the control diet from 116 days to 156 days (P=.006, log-rank test). Treatment with rapamycin reduced hydroxyproline content compared with the control diet (irradiation plus vehicle, 45.9 ± 11.8 μg per lung; irradiation plus rapamycin, 21.4 ± 6.0 μg per lung; P=.001) and reduced visible fibrotic foci. Rapamycin treatment attenuated interleukin 1β and transforming growth factor β induction in irradiated lungs compared with the control diet. Type II pneumocyte senescence after irradiation was reduced with rapamycin treatment at 16 weeks (3-fold reduction at 16 weeks, P<.001). Conclusions: Rapamycin protected against RIPF in a murine model. Rapamycin treatment reduced inflammatory cytokine expression, extracellular matrix production, and senescence in type II pneumocytes.« less

Mammalian Target of Rapamycin Inhibition With Rapamycin Mitigates Radiation-Induced Pulmonary Fibrosis in a Murine Model.

PubMed

Chung, Eun Joo; Sowers, Anastasia; Thetford, Angela; McKay-Corkum, Grace; Chung, Su I; Mitchell, James B; Citrin, Deborah E

2016-11-15

Radiation-induced pulmonary fibrosis (RIPF) is a late toxicity of therapeutic radiation. Signaling of the mammalian target of rapamycin drives several processes implicated in RIPF, including inflammatory cytokine production, fibroblast proliferation, and epithelial senescence. We sought to determine if mammalian target of rapamycin inhibition with rapamycin would mitigate RIPF. C57BL/6NCr mice received a diet formulated with rapamycin (14 mg/kg food) or a control diet 2 days before and continuing for 16 weeks after exposure to 5 daily fractions of 6 Gy of thoracic irradiation. Fibrosis was assessed with Masson trichrome staining and hydroxyproline assay. Cytokine expression was evaluated by quantitative real-time polymerase chain reaction. Senescence was assessed by staining for β-galactosidase activity. Administration of rapamycin extended the median survival of irradiated mice compared with the control diet from 116 days to 156 days (P=.006, log-rank test). Treatment with rapamycin reduced hydroxyproline content compared with the control diet (irradiation plus vehicle, 45.9 ± 11.8 μg per lung; irradiation plus rapamycin, 21.4 ± 6.0 μg per lung; P=.001) and reduced visible fibrotic foci. Rapamycin treatment attenuated interleukin 1β and transforming growth factor β induction in irradiated lungs compared with the control diet. Type II pneumocyte senescence after irradiation was reduced with rapamycin treatment at 16 weeks (3-fold reduction at 16 weeks, P<.001). Rapamycin protected against RIPF in a murine model. Rapamycin treatment reduced inflammatory cytokine expression, extracellular matrix production, and senescence in type II pneumocytes. Published by Elsevier Inc.

Short Communication: Rheological properties of blood serum of rats after irradiation with different gamma radiation doses in vivo.

PubMed

Abdelhalim, Mohamed Anwar K; Moussa, Sherif Aa; Ms, Al-Ayed

2016-01-01

The blood serum rheological properties open the door to find suitable radio-protectors and convenient therapy for many cases of radiation exposure. The present study aimed to investigate the rheological properties of rat blood serum at wide range of shear rates after whole body irradiation with different gamma radiation doses in vivo. Healthy male rats were divided into five groups; one control group and 4 irradiated groups. The irradiation process was carried out using Co60 source with dose rate of 0.883cG/sec. Several rheological parameters were measured using Brookfield LVDV-III Programmable rheometer. A significant increase in viscosity and shear stress was observed with 25 and 50Gy corresponding to each shear rate compared with the control; while a significant decrease observed with 75 and 100Gy. The viscosity exhibited a Non-Newtonian behaviour with the shear rate while shear stress values were linearly related with shear rate. The decrease in blood viscosity might be attributed to changes in molecular weight, pH sensitivity and protein structure. The changes in rheological properties of irradiated rats' blood serum might be attributed to destruction changes in the haematological and dimensional properties of rats' blood products.

Infrared Irradiation: Toward Green Chemistry, a Review.

PubMed

Escobedo, René; Miranda, René; Martínez, Joel

2016-03-26

This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included.

Infrared Irradiation: Toward Green Chemistry, a Review

PubMed Central

Escobedo, René; Miranda, René; Martínez, Joel

2016-01-01

This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included. PMID:27023535

Low-dose carbon ion irradiation effects on DNA damage and oxidative stress in the mouse testis

NASA Astrophysics Data System (ADS)

Liu, Yang; Long, Jing; Zhang, Luwei; Zhang, Hong; Liu, Bin; Zhao, Weiping; Wu, Zhehua

2011-01-01

To investigate the effects of low-dose carbon ion irradiation on reproductive system of mice, the testes of outbred Kunming strain mice were whole-body irradiated with 0, 0.05, 0.1, 0.5 and 1 Gy, respectively. We measured DNA double-strand breaks (DNA DSBs) and oxidative stress parameters including malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, and testis weight and sperm count at 12 h, 21 d and 35 d after irradiation in mouse testis. At 12 h postirradiation, a significant increase in DNA DSB level but no pronounced alterations in MDA content or SOD activity were observed in 0.5 and 1 Gy groups compared with the control group. At 21 d postirradiation, there was a significant reduction in sperm count and distinct enhancements of DSB level and MDA content in 0.5 and 1 Gy groups in comparison with control. At 35 d postirradiation, the levels of DNA DSBs and MDA, and SOD activity returned to the baseline except for the MDA content in 1 Gy (P < 0.05), while extreme falls of sperm count were still observed in 0.5 (P < 0.01) and 1 Gy (P < 0.01) groups. For the 0.05 or 0.1 Gy group, no differences were found in DNA DSB level and MDA content between control and at 12 h, 21 d and 35 d after irradiation, indicating that lower doses of carbon ion irradiation have no significant influence on spermatogenesis processes. In this study, male germ cells irradiated with over 0.5 Gy of carbon ions are difficult to repair completely marked by the sperm count. Furthermore, these data suggest that the deleterious effects may be chronic or delayed in reproductive system after whole-body exposure to acute high-dose carbon ions.

X-ray Irradiation Control of Frankliniella occidentalis and Frankliniella intonsa (Thysanoptera: Thripidae) in the Exportation of Freshly Cut Lily Flowers.

PubMed

Koo, Hyun-Na; Yun, Seung-Hwan; Kim, Hyun-Ju; Kim, Hyun Kyung; Kim, Gil-Hah

2017-04-01

Lily (Lilium longiflorum Thunb.) is the most representative bulb flower, and it is the third most important flower in the flower industry of South Korea after rose and chrysanthemum. To determine the efficacy of X-ray irradiation for use in quarantine processing, two species of flower thrips (Frankliniella intonsa (Trybom) and Frankliniella occidentalis (Pergande)) were placed in the top, middle, and bottom locations of lily boxes and irradiated with different X-ray doses. After irradiation with an X-ray dose of 150 Gy, the egg hatching of the two flower thrips was completely inhibited at every location in the lily boxes, and the irradiated F. intonsa and F. occidentalis nymphs failed to emerge as adult in every location of the lily boxes. When the adults were irradiated at 150 Gy, the fecundity of the two flower thrips was markedly lower than that of the untreated control groups. The F1 generation failed to hatch at the top and middle locations, whereas the F1 generation of both F. intonsa and F. occidentalis was not suppressed at the bottom locations, even at 200 Gy. However, hatching was perfectly inhibited at 300 Gy of X-ray irradiation. Also, X-rays did not affect the postharvest physiology of cut lilies. Therefore, a minimum dose of 300 Gy is recommended for the control of F. intonsa and F. occidentalis for the exportation of lily. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

GEH-4-42, 47; Hot pressed, I and E cooled fuel element irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neidner, R.

1959-11-02

In our continual effort to improve the present fuel elements which are irradiated in the numerous Hanford reactors, we have made what we believe to be a significant improvement in the hot pressing process for jacketing uranium fuel slugs. We are proposing a large scale evaluation testing program in the Hanford reactors but need the vital and basic information on the operating characteristics of this type slug under known and controlled operating conditions. We, therefore, have prepared two typical fuel slugs and will want them irradiated to about 1000 MWD/T exposure (this will require about four to five total cycles).

Low-level laser therapy (LLLT) reduces inflammatory infiltrate and enhances skeletal muscle repair: Histomorphometric parameters

NASA Astrophysics Data System (ADS)

Paiva-Oliveira, E. L.; Lima, N. C.; Silva, P. H.; Sousa, N. T. A.; Barbosa, F. S.; Orsini, M.; Silva, J. G.

2012-09-01

Low level laser therapy (LLLT) has been suggested as an effective therapeutics in inflammatory processes modulation and tissue repairing. However, there is a lack of studies that analyze the anti-inflammatory effects of the infrared lasers in muscular skeletal injury. The aim of this study was to investigate the effects of low-level laser therapy 904 nm in the repair process of skeletal muscle tissue. Swiss mice were submitted to cryoinjury and divided in test (LLLT-treated) and control groups. Histological sections were stained with hematoxylin-eosin to assess general morphology and inflammatory influx, and Picrossirus to quantify collagen fibers deposition. Our results showed significant reduction in inflammatory infiltrated in irradiated mice after 4 days of treatment compared to control ( p = 0.01). After 8 days, the irradiated group showed high levels at regenerating myofibers with significant statistically differences in relation at control group ( p < 0.01). Collagen deposition was significantly increased in the final stages of regeneration at test group, when compared with control group ( p = 0.05). Our data suggests that LLLT reduces the inflammatory response in the initial stages of injury and accelerates the process of muscular tissue repair.

Dose controlled low energy electron irradiator for biomolecular films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, S. V. K., E-mail: svkk@tifr.res.in; Tare, Satej T.; Upalekar, Yogesh V.

2016-03-15

We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at −20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface weremore » developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.« less

Effect of amino acid starvation on UV sensitivity of Lactobacillus acidophilus cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soška, J.; Nečasová, J.

1973-11-01

In Lactobacillus acidophilus cultures uv irradiated in the exponential phase of growth, the dose-survival curve was of the simple exponential type, without any shoulder. If the bacteria were subjected to amino acid starvation prior to irradiation, a shoulder corresponding to a quasi-threshold dose (D) of about 780 ergs/mm/sup 2/ appeared in the curve. The administration of protein- or RNA-synthesis inhibitors prior to irradiation had the same effect. The effect of pre-irradiation amino acid starvation was abolished by simuitaneous thymidine starvation. It was likewise abolished if amino acid starvation was followed by incubation in the presence of amino acids (without thymidine)more » and then by irradiation of the cells. Post-irradiation amino acid starvation did not lead to the formation of a shoulder but if combined with thymidine starvation it did. It can be concluded from the results that post-irradiation repair processes are facilitated or promoted if, during the post-irradiation interval DNA synthesis is delayed. This delay represents a compensation of the pre-irradiation increase of cellular DNA-content, taking place during inhibition of proteosynthesis. The post-irradiation administration of caffeine did not abolish the formation of the shoulder induced by pre-irradiation amino acid starvation; on the contrary, it induced its formation even in exponentially growing, irradiated control bacteria. (auth)« less

Use of Irradiated Foods

NASA Technical Reports Server (NTRS)

Brynjolfsson, A.

1985-01-01

The safety of irradiated foods is reviewed. Guidelines and regulations for processing irradiated foods are considered. The radiolytic products formed in food when it is irradiated and its wholesomeness is discussed. It is concluded that food irradiation processing is not a panacea for all problems in food processing but when properly used will serve the space station well.

Elimination of coliforms and Salmonella spp. in sheep meat by gamma irradiation treatment

PubMed Central

Henriques, Luciana Salles Vasconcelos; da Costa Henry, Fábio; Barbosa, João Batista; Ladeira, Silvania Alves; de Faria Pereira, Silvia Menezes; da Silva Antonio, Isabela Maria; Teixeira, Gina Nunes; Martins, Meire Lelis Leal; de Carvalho Vital, Helio; dos Prazeres Rodrigues, Dália; dos Reis, Eliane Moura Falavina

2013-01-01

This study aimed at evaluating the bacteriological effects of the treatment of sheep meat contaminated with total coliforms, coliforms at 45 °C and Salmonella spp. by using irradiation at doses of 3 kGy and 5 kGy. Thirty sheep meat samples were collected from animals located in Rio de Janeiro State, Brazil, and then grouped in three lots including 10 samples: non-irradiated (control); irradiated with 3 kGy; and irradiated with 5 kGy. Exposure to gamma radiation in a 137Cs source-driven irradiating facility was perfomed at the Nuclear Defense Section of the Brazilian Army Technological Center (CTEx) in Rio de Janeiro. The samples were kept under freezing temperature (−18 °C) until the analyses, which occurred in two and four months after irradiation. The results were interpreted by comparison with the standards of the current legislation and demonstrated that non-irradiated samples were outside the parameters established by law for all groups of bacteria studied. Gamma irradiation was effective in inactivating those microorganisms at both doses tested and the optimal dose was achieved at 3 kGy. The results have shown not only the need for sanitary conditions improvements in slaughter and processing of sheep meat but also the irradiation effectiveness to eliminate coliform bacteria and Salmonella spp. PMID:24688504

Quality changes of the Mediterranean horse mackerel ( Trachurus mediterraneus) during chilled storage: The effect of low-dose gamma irradiation

NASA Astrophysics Data System (ADS)

Mbarki, Raouf; Sadok, Saloua; Barkallah, Insaf

2009-04-01

Pelagic fishes represent the main Mediterranean fisheries in terms of quantity. However, waste and spoilage of pelagic fish are substantial for a variety of reasons, such as their high perishability and the lack or inadequate supply of ice and freezing facilities. In this work, fresh Mediterranean horse mackerel ( Trachurus mediterraneus) were irradiated at 1 and 2 kGy and stored in ice for 18 days. Quality changes during storage were followed by the determination of microbial counts, trimethylamine (TMA) and volatile basic nitrogen contents. Similarly, lipid composition and sensory analysis were carried out. Irradiation treatment was effective in reducing total bacterial counts throughout storage. Total basic volatile nitrogen content (TVB-N) and TMA levels increased in all lots with storage time, their concentrations being significantly reduced by irradiation, even when the lower level (1 kGy) was used. According to the quality index method, the control lot had a sensory shelf-life of 4 days, whereas those of the irradiated lots were extended by 5 days. Also, low-dose irradiation had no adverse effect on the nutritionally important polyunsaturated fatty acids (PUFA) of Mediterranean horse mackerel. In the same way, thiobarbituric acid-reactive substances values increased with irradiation during the first day, but these values were lower at the end of storage, compared to the control. Results confirm the practical advantages of using γ irradiation as an additional process to chilled storage to enhance the microbiological quality and to extend the shelf-life of small pelagic species.

Effect of low-level laser therapy on the modulation of the mitochondrial activity of macrophages

PubMed Central

Souza, Nadhia H. C.; Ferrari, Raquel A. M.; Silva, Daniela F. T.; Nunes, Fabio D.; Bussadori, Sandra K.; Fernandes, Kristianne P. S.

2014-01-01

BACKGROUND: Macrophages play a major role among the inflammatory cells that invade muscle tissue following an injury. Low-level laser therapy (LLLT) has long been used in clinical practice to accelerate the muscle repair process. However, little is known regarding its effect on macrophages. OBJECTIVE: This study evaluated the effect of LLLT on the mitochondrial activity (MA) of macrophages. METHOD: J774 macrophages were treated with lipopolysaccharide (LPS) and interferon - gamma (IFN-γ) (activation) for 24 h to simulate an inflammatory process, then irradiated with LLLT using two sets of parameters (780 nm; 70 mW; 3 J/cm2 and 660 nm; 15 mW; 7.5 J/cm2). Non-activated/non-irradiated cells composed the control group. MA was evaluated by the cell mitochondrial activity (MTT) assay (after 1, 3 and 5 days) in three independent experiments. The data were analyzed statistically. RESULTS: After 1 day of culture, activated and 780 nm irradiated macrophages showed lower MA than activated macrophages, but activated and 660 nm irradiated macrophages showed MA similar to activated cells. After 3 days, activated and irradiated (660 nm and 780 nm) macrophages showed greater MA than activated macrophages, and after 5 days, the activated and irradiated (660 nm and 780 nm) macrophages showed similar MA to the activated macrophages. CONCLUSIONS: These results show that 660 nm and 780 nm LLLT can modulate the cellular activation status of macrophages in inflammation, highlighting the importance of this resource and of the correct determination of its parameters in the repair process of skeletal muscle. PMID:25076002

Carbon protrusions on PTFE surface prepared by ion irradiation and chemical defluorination

NASA Astrophysics Data System (ADS)

Kobayashi, T.; Iwaki, M.

2006-01-01

A surface of PTFE was covered with small protrusions by ion-beam irradiation. In this study, we converted PTFE protrusions into carbon protrusions by a defluorination (carbonization) process using sodium vapor. The morphology, composition and structure were analyzed by SEM-EDX, Raman spectroscopy and TEM. The irradiated PTFE sheets were packed in evacuated glass tubes with a sodium block and kept at 473 K for 2-48 h. The samples were then rinsed in HCl and distilled water to remove NaF precipitates. The EDX measurement showed that the NaF precipitates were completely removed by washing, and the percentage of carbon atoms was controlled from 60% to 99% by the treatment. Raman spectra showed that graphite structures grow during the defluorination process. TEM micrographs showed that the protrusions have a bubble structure and are covered with a thin wall. The carbonized protrusions were conductive and grew perpendicular to the substrate.

Rapid and reversible photoinduced switching of a rotaxane crystal

NASA Astrophysics Data System (ADS)

Chen, Kai-Jen; Tsai, Ya-Ching; Suzaki, Yuji; Osakada, Kohtaro; Miura, Atsushi; Horie, Masaki

2016-11-01

Crystalline phase transitions caused by external stimuli have been used to detect physical changes in the solid-state properties. This study presents the mechanical switching of crystals of ferrocene-containing rotaxane controlled by focused laser light. The expansion and contraction of the crystals can be driven by turning on and off laser light at 445 nm. The irradiation-induced expansion of the crystal involves elongation along the a, b and c axes at 30 °C, whereas heating of the crystal at 105 °C causes the shortening of c axis. The expansions reversibly occur and have the advantage of a rapid relaxation (reverse) process. Single-crystal X-ray crystallography reveals the detailed structural changes of the molecules, corresponding to a change in the size of the crystals on laser irradiation. This molecular crystal behaviour induced by laser irradiation, is demonstrated for the remote control of objects, namely, microparticle transport and microswitching in an electric circuit.

ELECTRON IRRADIATION OF SOLIDS

DOEpatents

Damask, A.C.

1959-11-01

A method is presented for altering physical properties of certain solids, such as enhancing the usefulness of solids, in which atomic interchange occurs through a vacancy mechanism, electron irradiation, and temperature control. In a centain class of metals, alloys, and semiconductors, diffusion or displacement of atoms occurs through a vacancy mechanism, i.e., an atom can only move when there exists a vacant atomic or lattice site in an adjacent position. In the process of the invention highenergy electron irradiation produces additional vacancies in a solid over those normally occurring at a given temperature and allows diffusion of the component atoms of the solid to proceed at temperatures at which it would not occur under thermal means alone in any reasonable length of time. The invention offers a precise way to increase the number of vacancies and thereby, to a controlled degree, change the physical properties of some materials, such as resistivity or hardness.

Characterization and application of two kinds of ESR dosimeters

NASA Astrophysics Data System (ADS)

Marchioni, Eric; Pabst, Jean-Yves; Kuntz, Florent

2002-09-01

Many previous papers described the use of low-concentration alanine pellets, powder or films for industrial high-dose application, but very few authors presented applications of such dosimeters to the low-dose range used for wastewater, flowers or radiotherapy treatment. The present paper describes the large-scale manufacturing process of high-concentration alanine pellets used for radiotherapy dose control in some French hospitals. The fading process due to sunlight exposure has been evaluated by means of direct UV light irradiation. The major disadvantage of alanine is its strong solubility in water (the pellets are completely dissolved when immersed for 10 min in pure water). The use of barium sulphate, not soluble in water, made it possible to carry out dosimetric measurements even when the dosimeter is completely immersed in water or stored after irradiation in high humidity levels. The paper presents manufacturing process of barium sulphate pellets, their dosimetric characteristics and one application of this dosimeter for the control of the absorbed doses during wastewater treatments.

Biostimulative effects of 809 nm diode laser on cutaneous skin wounds

NASA Astrophysics Data System (ADS)

Solmaz, Hakan; Gülsoy, Murat; Ülgen, Yekta

2015-03-01

The use of low-level laser therapy (LLLT) for therapeutic purposes in medicine has become widespread recently. There are many studies in literature supporting the idea of therapeutic effects of laser irradiation on biological tissues. The aim of this study is to investigate the biostimulative effect of 809nm infrared laser irradiation on the healing process of cutaneous incisional skin wounds. 3-4 months old male Wistar Albino rats weighing 300 to 350 gr were used throughout this study. Lowlevel laser therapy was applied through local irradiation of 809nm infrared laser on open skin incisional wounds of 1 cm length. Each animal had six identical incisions on their right and left dorsal region symmetrical to each other. The wounds were separated into three groups of control, 1 J/cm2 and 3 J/cm2 of laser irradiation. Two of these six wounds were kept as control group and did not receive any laser application. Rest of the incisions was irradiated with continuous diode laser of 809nm in wavelength and 20mW power output. Two of them were subjected to laser irradiation of 1 J/cm2 and the other two were subjected to laser light with energy density of 3 J/cm2. Biostimulation effects of irradiation were studied by means of tensile strength tests and histological examinations. Wounded skin samples were morphologically examined and removed for mechanical and histological examinations at days 3, 5 and 7 following the laser applications. Three of the six fragments of skin incisions including a portion of peripheral healthy tissue from each animal were subjected to mechanical tests by means of a universal tensile test machine, whereas the other three samples were embedded in paraffin and stained with hematoxylin and eosin for histological examinations. The findings of the study show that tissue repair following laser irradiation of 809nm has been accelerated in terms of tissue morphology, strength and cellular content. These results seem to be consistent with the results of many researches previously published in literature and support the idea that LLLT has therapeutic effect on wound healing process.

Detection and original dose assessment of egg powders subjected to gamma irradiation by using ESR technique

NASA Astrophysics Data System (ADS)

Aydın, Talat

2015-09-01

ESR (electron spin resonance) techniques were applied for detection and original dose estimation to radiation-processed egg powders. The un-irradiated (control) egg powders showed a single resonance line centered at g=2.0086±0.0005, 2.0081±0.0005, 2.0082±0.0005 (native signal) for yolk, white and whole egg, respectively. Irradiation induced at least one additional intense singlet overlapping to the control signal and caused a significant increase in signal intensity without any changes in spectral patterns. Responses of egg powders to different gamma radiation doses in the range 0-10 kGy were examined. The stability of the radiation-induced ESR signal of irradiated egg powders were investigated over a storage period of about 5 months. Additive reirradiation of the egg powders produces a reproducible dose response function, which can be used to assess the initial dose by back-extrapolation. The additive dose method gives an estimation of the original dose within ±12% at the end of the 720 h storage period.

The impact of solar radiation on the heating and cooling of buildings

NASA Astrophysics Data System (ADS)

Witmer, Lucas

This work focuses on the impact of solar energy on the heating and cooling of buildings. The sun can be the primary driver for building cooling loads as well as a significant source of heat in the winter. Methods are presented for the calculation of solar energy incident on tilted surfaces and the irradiance data source options. A key deficiency in current building energy modeling softwares is reviewed with a demonstration of the impact of calculating for shade on opaque surfaces. Several tools include methods for calculating shade incident on windows, while none do so automatically for opaque surfaces. The resulting calculations for fully irradiated wall surfaces underestimate building energy consumption in the winter and overestimate in the summer by significant margins. A method has been developed for processing and filtering solar irradiance data based on local shading. This method is used to compare situations where a model predictive control system can make poor decisions for building comfort control. An MPC system informed by poor quality solar data will negatively impact comfort in perimeter building zones during the cooling season. The direct component of irradiance is necessary for the calculation of irradiance on a tilted surface. Using graphical analysis and conditional probability distributions, this work demonstrates a proof of concept for estimating direct normal irradiance from a multi-pyranometer array by leveraging inter-surface relationships without directly inverting a sky model.

[Effect of External Irradiation and Immobilization Stress on the Reproductive System of Male Rats].

PubMed

Vereschako, G G; Tshueshova, N V; Gorokh, G A; Kozlov, I G; Naumov, A D

2016-01-01

We studied the state of the reproductive system of male rats after irradiation at a dose of 2.0 Gy, immobilization stress (6 hours/day for 7 days) and their combined effects. On the 30th day after the combined treatment (37 days after irradiation) a decrease in the testicular weight by almost 50% compared with the control and lesions connected with the process of spermatogenesis are observed. In the remote period--on the 60th day (67th after irradiation) the effect of irradiation and irradiation in combination with immobilization stress leads to a sharp drop in the number of epididymal sperm (up to 18% of the control), and a reduction of their viability. The reaction ofthe reproductive system to the immobilization stress is expressed in a certain increase in the mass of the testes and epididymis, moderate imbalances in the composition of spermatogenic cells in the testis tissue, and in the long term--in the increased number of epididymal sperm and the decrease in their viability. Changes of testosterone in the blood serum, especially significant for the combined effect, reflect impairments of the regulation of the reproductive system of males under these conditions. With regard to individual indicators of the reproductive system of male rats in some cases, the- combined effects of radiation and stress had a synergistic, or, on the contrary, antagonistic character.

Effects of high-frequency near-infrared diode laser irradiation on the proliferation and migration of mouse calvarial osteoblasts.

PubMed

Kunimatsu, Ryo; Gunji, Hidemi; Tsuka, Yuji; Yoshimi, Yuki; Awada, Tetsuya; Sumi, Keisuke; Nakajima, Kengo; Kimura, Aya; Hiraki, Tomoka; Abe, Takaharu; Naoto, Hirose; Yanoshita, Makoto; Tanimoto, Kotaro

2018-07-01

Laser irradiation activates a range of cellular processes and can promote tissue repair. Here, we examined the effects of high-frequency near-infrared (NIR) diode laser irradiation on the proliferation and migration of mouse calvarial osteoblastic cells (MC3T3-E1). MC3T3-E1 cells were cultured and exposed to high-frequency (30 kHz) 910-nm diode laser irradiation at a dose of 0, 1.42, 2.85, 5.7, or 17.1 J/cm 2 . Cell proliferation was evaluated with BrdU and ATP concentration assays. Cell migration was analyzed by quantitative assessment of wound healing using the Incucyt ® ZOOM system. In addition, phosphorylation of mitogen-activated protein kinase (MAPK) family members including p38 mitogen-activated protein kinase (p38), stress-activated protein kinase/Jun-amino-terminal kinase (SAPK/JNK), and extracellular signal-regulated protein kinase (ERK)1/2) after laser irradiation was examined with western blotting. Compared to the control, cell proliferation was significantly increased by laser irradiation at a dose of 2.85, 5.7, or 17.1 J/cm 2 . Laser irradiation at a dose of 2.85 J/cm 2 induced MC3T3-E1 cells to migrate more rapidly than non-irradiated control cells. Irradiation with the high-frequency 910-nm diode laser at a dose of 2.85 J/cm 2 induced phosphorylation of MAPK/ERK1/2 15 and 30 min later. However, phosphorylation of p38 MAPK and SAPK/JNK was not changed by NIR diode laser irradiation at a dose of 2.85 J/cm 2 . Irradiation with a high-frequency NIR diode laser increased cell division and migration of MT3T3-E1 cells, possibly via MAPK/ERK signaling. These observations may be important for enhancing proliferation and migration of osteoblasts to improve regeneration of bone tissues.

Polarization of electron-beam irradiated LDPE films: contribution to charge generation and transport

NASA Astrophysics Data System (ADS)

Banda, M. E.; Griseri, V.; Teyssèdre, G.; Le Roy, S.

2018-04-01

Electron-beam irradiation is an alternative way to generate charges in insulating materials, at controlled position and quantity, in order to monitor their behaviour in regard to transport phenomena under the space charge induced electric field or external field applied. In this study, low density polyethylene (LDPE) films were irradiated by a 80 keV electron-beam with a flux of 1 nA cm‑2 during 10 min in an irradiation chamber under vacuum conditions, and were then characterized outside the chamber using three experimental methods. The electrical behaviour of the irradiated material was assessed by space charge measurements using the pulsed electro-acoustic (PEA) method under dc stress. The influence of the applied electric field polarity and amplitude has been tested in order to better understand the charge behaviour after electron-beam irradiation. Fourier transform infra-red spectroscopy (FTIR) and photoluminescence (PL) measurements were performed to evaluate the impact of the electron beam irradiation, i.e. deposited charges and energy, on the chemical structure of the irradiated samples. The present results show that the electrical behaviour in LDPE after irradiation is mostly driven by charges, i.e. by physical process functions of the electric field, and that changes in the chemical structure seems to be mild.

Impact of electron beam irradiation on quality of sea buckthorn (Hippophae rhamnoides L.) oil.

PubMed

Nemţanu, Monica R; Braşoveanu, Mirela

2016-03-30

Sea buckthorn oil is a valuable product that can be incorporated into daily foodstuffs, cosmetics or pharmaceuticals. The effect of accelerated electron irradiation up to 8 kGy on quality characteristics of sea buckthorn oil was investigated in this study. Irradiation had no significant influence on phenolic content. Conversely, carotenoid content, antioxidant activity, and oxidative status suffered alterations as the irradiation dose increased. Although no colour changes were visible for oil irradiated up to 3 kGy, the total colour difference indicated clearly changes that involved a two-step pattern associated with slow degradation of oil colour up to 3 kGy, followed by a fast degradation up to 8 kGy. Some changes of the oil spectral features related to the frequency and intensity of some bands have been found after irradiation, indicating an alteration of the structural integrity induced by irradiation. The present investigation may be a useful starting point for irradiation processing of food or non-food matrices containing sea buckthorn oil. Thus, sea buckthorn oil safety can be ensured with minimal undesirable changes in its quality by applying irradiation doses up to 3 kGy, which allow control of the microbial contamination depending on microorganism type and initial microbial load. © 2015 Society of Chemical Industry.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vasileiadis, Thomas; Department of Materials Science, University of Patras, GR-26504 Rio-Patras; Yannopoulos, Spyros N., E-mail: sny@iceht.forth.gr

Controlled photo-induced oxidation and amorphization of elemental trigonal tellurium are achieved by laser irradiation at optical wavelengths. These processes are monitored in situ by time-resolved Raman scattering and ex situ by electron microscopies. Ultrathin TeO₂ films form on Te surfaces, as a result of irradiation, with an interface layer of amorphous Te intervening between them. It is shown that irradiation, apart from enabling the controllable transformation of bulk Te to one-dimensional nanostructures, such as Te nanotubes and hybrid core-Te/sheath-TeO₂ nanowires, causes also a series of light-driven (athermal) phase transitions involving the crystallization of the amorphous TeO₂ layers and its transformationmore » to a multiplicity of crystalline phases including the γ-, β-, and α-TeO₂ crystalline phases. The kinetics of the above photo-induced processes is investigated by Raman scattering at various laser fluences revealing exponential and non-exponential kinetics at low and high fluence, respectively. In addition, the formation of ultrathin (less than 10 nm) layers of amorphous TeO₂ offers the possibility to explore structural transitions in 2D glasses by observing changes in the short- and medium-range structural order induced by spatial confinement.« less

Neurobehavioural sequelae following cranial irradiation and chemotherapy in children: an analysis of risk factors.

PubMed

Anderson, V; Godber, T; Smibert, E; Ekert, H

1997-01-01

Neurobehavioural deficits are commonly reported following treatment for childhood cancers. This study examined the impact of cranial irradiation (CRT) and chemotherapy in children, aiming to identify factors detrimental to long-term outcome. The study compared survivors of acute lymphoblastic leukemia (ALL), treated with CRT and chemotherapy (CRT group: n = 100), survivors of cancers treated with chemotherapy only (n = 50) and healthy controls (n = 100) for intelligence, academic achievement, information processing, learning, and executive function. CRT and chemotherapy in combination were associated with reduced intelligence, educational skill, immediate memory, processing speed, and executive function. Children treated with chemotherapy alone exhibited subtle information processing deficits. Within the CRT group, younger age at treatment was predictive of deficits in non-verbal ability, educational skills and executive functions. High dose CRT was associated with poorer information processing and lower arithmetic ability.

The effect of low-intensity laser therapy on wound healing in Streptozotocin-induced diabetic rats

NASA Astrophysics Data System (ADS)

Rabelo, Sylvia B.; Villaverde, Antonio G. J. B.; Salgado, Miguel A. C.; Melo, Milene d. S.; Nicolau, Renata A.; Pacheco, Marcos T. T.

2004-10-01

Diabetes Mellitus is a condition that results in a delay of the wound healing process, that is associated with an insufficient production of collagen, a decrease of the amount of collagen fibrils and deficient blood flow in the wound area. It is sugested that Low Intensity Laser Therapy acts by improving wound healing in normal organisms, accelerating tissue regeneration. The aim of this work was to investigate the biostimulatory effect of the HeNe laser irradiation, at 632.8 nm, on wound healing in 15 male rats suffering from diabetes induced by Streptozotocin, compared to 15 control diabetic animals. Irradiation parameters were: laser power of 15mW, exposition time of 17 s., irradiated area of 0.025 cm2 and laser energy density of 10 J/cm2. Full-thickness skin squared samples, with 5 mm of non-injured tissue around the wound, were obtained at 4, 7 and 15 days after wounding procedure (5 treated and 5 control animals each time). The histopathologic analysis performed by haematoxylin-cosin staining. Results suggested that the irradiation of diabetic rats was efficient for wound healing. Treated group presented better quality of the wound tissues by the macroscopic observation than control group and the microscopic analysis demonstrated that treated animals had better histopathologic evaluation than non treated.

THE FORMATION OF BONE CALLUS DURING RADIATION SICKNESS (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nazarishvill, G.P.; Vepkhvadze, R.Ya.; Vakhtangashvili, T.A.

1957-01-01

>Six dogs were irradiated with an x-ray dose of 408 r, and the skin bone was thee broken immediately after radiation. The healing process was followed by x rays in the control group of dogs in which a well-developed bone callus could be observed on the 50th day. No sign of the formation of a bone callus at the fracture site could be observed in any of the irradiated dogs. Even on the l02nd day after the fracture a wide slit could be seen on thee x-ray diagram at the point of fracture where the bones had not knit togethermore » in the irradiated dogs. (TTT)« less

Comparison of measured and calculated composition of irradiated EBR-II blanket assemblies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grimm, K. N.

1998-07-13

In anticipation of processing irradiated EBR-II depleted uranium blanket subassemblies in the Fuel Conditioning Facility (FCF) at ANL-West, it has been possible to obtain a limited set of destructive chemical analyses of samples from a single EBR-II blanket subassembly. Comparison of calculated values with these measurements is being used to validate a depletion methodology based on a limited number of generic models of EBR-II to simulate the irradiation history of these subassemblies. Initial comparisons indicate these methods are adequate to meet the operations and material control and accountancy (MC and A) requirements for the FCF, but also indicate several shortcomingsmore » which may be corrected or improved.« less

Low-intensity LED therapy (658 nm) on burn healing: a series of cases.

PubMed

de Oliveira, Rauirys Alencar; Boson, Luara Lis Barbosa; Portela, Seísa Marina Martins; Filho, Antônio Luiz Martins Maia; de Oliveira Santiago, Denyberg

2018-05-01

The objective of this study was to evaluate the effects of LED on burns healing. Five patients with skin burns were submitted to photobiomodulation by LED, GaAsIP diode, (λ 658 nm) with 40 mW, 7 J/cm 2 on every other day. Biopsies of burned skin were performed and the healing process was photographed. Patients with bilateral burns were used as self-control, having one limb being irradiated and the contralateral limb irradiated with placebo. The burns treated with LED showed higher epithelization, with keratinocytes and fibroblasts proliferation, increased collagen synthesis, decreased pain, and pruritus. In conclusion, there was a faster clinical improvement in the irradiated limbs.

Facile Dry Surface Cleaning of Graphene by UV Treatment

NASA Astrophysics Data System (ADS)

Kim, Jin Hong; Haidari, Mohd Musaib; Choi, Jin Sik; Kim, Hakseong; Yu, Young-Jun; Park, Jonghyurk

2018-05-01

Graphene has been considered an ideal material for application in transparent lightweight wearable electronics due to its extraordinary mechanical, optical, and electrical properties originating from its ordered hexagonal carbon atomic lattice in a layer. Precise surface control is critical in maximizing its performance in electronic applications. Graphene grown by chemical vapor deposition is widely used but it produces polymeric residue following wet/chemical transfer process, which strongly affects its intrinsic electrical properties and limits the doping efficiency by adsorption. Here, we introduce a facile dry-cleaning method based on UV irradiation to eliminate the organic residues even after device fabrication. Through surface topography, Raman analysis, and electrical transport measurement characteristics, we confirm that the optimized UV treatment can recover the clean graphene surface and improve graphene-FET performance more effectively than thermal treatment. We propose our UV irradiation method as a systematically controllable and damage-free post process for application in large-area devices.

Radiation processing as a post-harvest quarantine control for raisins, dried figs and dried apricots

NASA Astrophysics Data System (ADS)

Cetinkaya, N.; Ozyardımci, B.; Denli, E.; Ic, E.

2006-03-01

The commercially packed samples of raisins, dried figs and dried apricots were irradiated using doses in the range of 0.5-1.0 kGy for disinfestation and 0.5-5.0 kGy for sensory analysis with the dose rate ranging from 1.44 to 1.92 kGy/h. Pests on dried fruits were evaluated after 0, 1, 2 and 3 months of storage for irradiated dried figs and 1, 3, 6 and 12 months of storage for raisins and dried apricots. Sensory analysis of dried figs, dried apricots and raisins were carried out after 0, 1, 3, 6 and 12 months of storage. The results indicated that radiation processing at low doses, (˜1.0 kGy) is an effective post-harvest treatment and quarantine control for these products with no adverse effects on sensory (marketing) attributes.

Laser Material Processing for Microengineering Applications

NASA Technical Reports Server (NTRS)

Helvajian, H.

1995-01-01

The processing of materials via laser irradiation is presented in a brief survey. Various techniques currently used in laser processing are outlined and the significance to the development of space qualified microinstrumentation are identified. In general the laser processing technique permits the transferring of patterns (i.e. lithography), machining (i.e. with nanometer precision), material deposition (e.g., metals, dielectrics), the removal of contaminants/debris/passivation layers and the ability to provide process control through spectroscopy.

STATUS OF TRISO FUEL IRRADIATIONS IN THE ADVANCED TEST REACTOR SUPPORTING HIGH-TEMPERATURE GAS-COOLED REACTOR DESIGNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davenport, Michael; Petti, D. A.; Palmer, Joe

2016-11-01

The United States Department of Energy’s Advanced Reactor Technologies (ART) Advanced Gas Reactor (AGR) Fuel Development and Qualification Program is irradiating up to seven low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States. The experiments will be irradiated over the next several years to demonstrate and qualify new TRISO coated particle fuel for use in high temperature gas reactors. The goals of the experimentsmore » are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which will each consist of several independent capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gas will also have on-line fission product monitoring on its effluent to track performance of the fuel in each individual capsule during irradiation. The first experiment (designated AGR-1) started irradiation in December 2006 and was completed in November 2009. The second experiment (AGR-2) started irradiation in June 2010 and completed in October 2013. The third and fourth experiments have been combined into a single experiment designated (AGR-3/4), which started its irradiation in December 2011 and completed in April 2014. Since the purpose of this experiment was to provide data on fission product migration and retention in the NGNP reactor, the design of this experiment was significantly different from the first two experiments, though the control and monitoring systems are very similar. The final experiment, AGR-5/6/7, is scheduled to begin irradiation in early summer 2017.« less

Mechanical properties of acellular mouse lungs after sterilization by gamma irradiation.

PubMed

Uriarte, Juan J; Nonaka, Paula N; Campillo, Noelia; Palma, Renata K; Melo, Esther; de Oliveira, Luis V F; Navajas, Daniel; Farré, Ramon

2014-12-01

Lung bioengineering using decellularized organ scaffolds is a potential alternative for lung transplantation. Clinical application will require donor scaffold sterilization. As gamma-irradiation is a conventional method for sterilizing tissue preparations for clinical application, the aim of this study was to evaluate the effects of lung scaffold sterilization by gamma irradiation on the mechanical properties of the acellular lung when subjected to the artificial ventilation maneuvers typical within bioreactors. Twenty-six mouse lungs were decellularized by a sodium dodecyl sulfate detergent protocol. Eight lungs were used as controls and 18 of them were submitted to a 31kGy gamma irradiation sterilization process (9 kept frozen in dry ice and 9 at room temperature). Mechanical properties of acellular lungs were measured before and after irradiation. Lung resistance (RL) and elastance (EL) were computed by linear regression fitting of recorded signals during mechanical ventilation (tracheal pressure, flow and volume). Static (Est) and dynamic (Edyn) elastances were obtained by the end-inspiratory occlusion method. After irradiation lungs presented higher values of resistance and elastance than before irradiation: RL increased by 41.1% (room temperature irradiation) and 32.8% (frozen irradiation) and EL increased by 41.8% (room temperature irradiation) and 31.8% (frozen irradiation). Similar increases were induced by irradiation in Est and Edyn. Scanning electron microscopy showed slight structural changes after irradiation, particularly those kept frozen. Sterilization by gamma irradiation at a conventional dose to ensure sterilization modifies acellular lung mechanics, with potential implications for lung bioengineering. Copyright © 2014 Elsevier Ltd. All rights reserved.

The status of food irradiation technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sivinski, J.S.

1989-01-01

Irradiation is a mature technology for many uses, such as medical product sterilization, crosslinking of plastics, application of coatings, stabilization of natural and synthetic rubbers prior to vulcanization, and in plant genetics. It also has many potential applications in the food and agriculture industries, especially in the postharvest activities associated with processing, storing, and distribution and in utilization and consumption. The safety of food irradiation has been thoroughly studied and established by distinguished scientists of international stature and unimpeachable credentials. Approximately 30 countries permit food irradiation and it is commercially used in 21. Parasites are of serious concern since theirmore » impact on human health and economic productivity is significant, especially in developing countries with sanitation and food control problems. Parasites in meat and fish can be rendered sterile or inactivated with irradiation, and the potential for improved human health is significant. The second area for immediate use of irradiation is in meeting plant quarantine requirements. The benefits described above and the approval of the scientific community are moving the technology toward greater utilization.« less

Chemical composition and lipoxygenase activity in soybeans (Glycine max L. Merr.) submitted to gamma irradiation

NASA Astrophysics Data System (ADS)

Barros, Érica Amanda de; Broetto, Fernando; Bressan, Dayanne F.; Sartori, Maria M. P.; Costa, Vladimir E.

2014-05-01

Soybeans are an important food due to their functional and nutritional characteristics. However, consumption by western populations is limited by the astringent taste of soybeans and their derivatives which results from the action of lipoxygenase, an enzyme activated during product processing. The aim of this study was to evaluate the effect of gamma irradiation on the chemical composition and specific activity of lipoxygenase in different soybean cultivars. Soybeans were stored in plastic bags and irradiated with doses of 2.5, 5 and 10 kGy. The chemical composition (moisture, protein, lipids, ashes, crude fiber, and carbohydrates) and lipoxygenase specific activity were determined for each sample. Gamma irradiation induced a small increase of protein and lipid content in some soybean cultivars, which did not exceed the highest content of 5% and 26%, respectively, when compared to control. Lipoxygenase specific activity decreased in the three cultivars with increasing gamma irradiation dose. In conclusion, the gamma irradiation doses used are suitable to inactivate part of lipoxygenase while not causing expressive changes in the chemical composition of the cultivars studied.

Investigation of solar cells fabricated on low-cost silicon sheet materials using 1 MeV electron irradiation

NASA Technical Reports Server (NTRS)

Kachare, A. H.; Hyland, S. L.; Garlick, G. F. J.

1981-01-01

The use of high energy electron irradiation is investigated as a controlled means to study in more detail the junction depletion layer processes of solar cells made on various low-cost silicon sheet materials. Results show that solar cells made on Czochralski grown silicon exhibit enhancement of spectral response in the shorter wavelength region when irradiated with high energy electrons. The base region damage can be reduced by subsequent annealing at 450 C which restores the degraded longer wavelength response, although the shorter wavelength enhancement persists. The second diode component of the cell dark forward bias current is also reduced by electron irradiation, while thermal annealing at 450 C without electron irradiation can also produce these same effects. Electron irradiation produces small changes in the shorter wavelength spectral responses and junction improvements in solar cells made on WEB, EFG, and HEM silicon. It is concluded that these beneficial effects on cell characteristics are due to the reduction of oxygen associated deep level recombination centers in the N(+) diffused layer and in the junction.

ASEPTIC INFLAMMATION IN THE LUNGS IN ACUTE RADIATION SICKNESS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivanov, A.E.

1963-09-01

Inflammation in the lungs of irradiated rabbits at the site of turpentine injection has much in common with the inflammatory changes arising in other tissues and organs during local irradiation or acute radiation sickness. The fact that the inflammatory changes under different conditions of irradiation are similar in type regardless of the character of the inflammatory agent suggests that the phenomenon has a common mechanism. The absence of polymorphonuclear (eosinophtlic) leukocytes from inflammatory foci in irradiated rabbits is due not only to the developing leukopenia, but also to a disturbance of the leukocyte emigration process into the inflammatory focus. Inmore » irradiated rabbits in cortrast to the controls, the normal arrangement of the fibrous structures is preserved in the necrotic lung tissue at the site of turpentine injection. In animals with severe acute radiation sickness induced by external irradiation in sublethal doses, the ability of the organism to respond to introduction of an inflammatory agent by an increase in the number of leukocytes in the blood and by a rise of the body temperature is to some extent preserved. (auth)« less

Effect of ionizing radiation on some quality attributes of nutraceutically valued lotus seeds.

PubMed

Bhat, Rajeev; Karim, A A

2009-01-01

Radiation processing has been employed successfully for value addition of food and agricultural products. Preliminary studies were undertaken to evaluate the changes induced by ionizing radiation (up to 30 kGy), in the form of gamma irradiation and electron beam irradiation, on some quality attributes and nutritive values of nutraceutically valued lotus seeds. Significant loss in seed firmness was recorded between control and irradiated seeds, irrespective of radiation source. Similarly, the specific viscosity of irradiated lotus seeds decreased significantly up to a dose of 7.5 kGy. Starch increased after exposure to gamma or electron beam irradiation, whereas the total phenolic contents were decreased. Gamma irradiation revealed an enhancement in protein, while the electron beam showed a decrease. Partial oxidation of the seeds during radiation treatments might have occurred as evidenced from the decomposition profiles (thermogravimetry) during heating. It is evident that ionizing radiation brought about significant and variable changes in the quality and nutritive values of lotus seed. Further exploration of this technology for safety and quality is warranted.

Effect of photodynamic therapy on mouse platelets

NASA Astrophysics Data System (ADS)

Zhou, Chuannong; Chi, Shunji; Deng, Jinsheng; Zhang, Hua; Liang, Junlin; Ha, Xian-wen

1993-03-01

Normal mice received hematoporphyrin derivative (10 mg/kg iv) immediately, 24 or 48 hrs prior to red light irradiation. The blood was collected and the platelet-rich plasma was irradiated by red light (100 J/cm2). The platelets were fixed immediately, 8 or 16 hrs after irradiation, and processed for EM examination. In comparison with those of control mice, the platelets of all experimental mice showed structural changes: 16 hrs after irradiation all platelets were necrotized; 8 hrs after irradiation almost one fourth of the platelets were necrotized and the remaining were considerably damaged; immediately after irradiation a small number of platelets became necrotic and most other platelets were swollen and deformed, often with many cytoplasmic projections and considerable dilatation of the canalicular membrane system. Our findings provided a clear evidence that platelets are highly sensitive to PDT action and can be directly and rapidly injured by PDT even in the absence of vascular endothelial cells. Our results give firm support to the hypothesis that both endothelial cells and platelets may play an important role in the initiation of early vascular damage and microcirculatory alterations induced by PDT in vivo.

Gamma irradiation as a phytosanitary treatment for fresh pome fruits produced in Patagonia

NASA Astrophysics Data System (ADS)

Pérez, J.; Lires, C.; Horak, C.; Pawlak, E.; Docters, A.; Kairiyama, E.

2009-07-01

Argentina produces 1.8 million tons/year of apples ( Malus domestica L.) and pears ( Pyrus communis L.) in the Patagonia region. Cydia pomonella, codling moth, and Grapholita molesta, Oriental fruit moth, ( Lepidoptera: Tortricidae) are quarantine pests in pome fruits. Irradiation is a promising phytosanitary treatment because a dose of 200 Gy completely prevents pest adult emergence. A pilot irradiation process of commercially packaged 'Red Delicious' apples and 'Packham's Triumph' pears was performed in an irradiation facility with a Cobalt 60 source. Quality analyses were carried out at 0, 2, 4, 6 and 8 months of storage (1 °C, RH 99%) to evaluate fruit tolerance at 200, 400 and 800 Gy. Irradiation at 200 and 400 Gy had no undesirable effects on fruit quality (pulp firmness, external colour, soluble solids content (SSC), titratable acidity (TA) and sensory evaluations). Irradiation of 'Red Delicious' apples and 'Packham's Triumph' pears can be applied as a commercial quarantine treatment with a minimum absorbed dose of 200 Gy (to control codling moth and Oriental fruit moth) and <800 Gy (according to quality results).

New irradiation facilities for development of production methods of medical radionuclides at cyclotrons at Forschungszentrum Jülich

NASA Astrophysics Data System (ADS)

Spellerberg, S.; Scholten, B.; Spahn, I.; Felden, O.; Gebel, R.; Qaim, S. M.; Bai, M.; Neumaier, B.

2017-05-01

An essential basis for research and development work on radiopharmaceuticals is the efficient production of radionuclides of high quality. In this process research-oriented studies aiming for elucidation of biochemical processes require novel products. The radionuclide development at INM-5 entails basic research, e.g. the determination of nuclear reaction data, as well as technical aspects of practical production, such as high-current targetry, chemical separation, formulation and quality control. In this work developments, adaptation and optimization of irradiation facilities at the BC 1710, JULIC as Injector of COSY and COSY itself are summarized, which shall allow the extension of radionuclide production possibilities, aiming at innovations in medical applications.

Method for extracting long-equivalent wavelength interferometric information

NASA Technical Reports Server (NTRS)

Hochberg, Eric B. (Inventor)

1991-01-01

A process for extracting long-equivalent wavelength interferometric information from a two-wavelength polychromatic or achromatic interferometer. The process comprises the steps of simultaneously recording a non-linear sum of two different frequency visible light interferograms on a high resolution film and then placing the developed film in an optical train for Fourier transformation, low pass spatial filtering and inverse transformation of the film image to produce low spatial frequency fringes corresponding to a long-equivalent wavelength interferogram. The recorded non-linear sum irradiance derived from the two-wavelength interferometer is obtained by controlling the exposure so that the average interferogram irradiance is set at either the noise level threshold or the saturation level threshold of the film.

Assessment of the effect of wave device application on morphological changes in organs and cells of irradiated animals.

PubMed

Bebeshko, V; Homolyako, I; Grynchyshyn, V

2017-12-01

To study the effect of the Device for wave influence on biological objects on the prevention of the development of acute radiation sickness and chronic radiation syndrome in vivo. The studies were performed on white rats irradiated at a dose of 8 Gy. The experimental group of irradiated rats was treated with a wave Device (Patent of Ukraine No. 53568) once, for 2.5 min, 1.5 h after irradiation. Their organs were processed by standard histologic methods. In the demagnetized rats, dystrophic changes in cells and tissues of liver, lungs, kidneys, brain, bone marrow and spleen were insignificant in 60 days compared to the control non-demagnetized group of animals. The Device reduced the magnetic charge of magneto-containing elements and their compounds in the organism of the irradiated animals, and decreased the formation of reactive oxygen species, which play a key role in the development of radiation-induced diseases.

Ion irradiation induced nucleation and growth of nanoparticles in amorphous silicon carbide at elevated temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Limin; Jiang, Weilin; Ai, Wensi

Ion irradiation induced crystallization in as-deposited amorphous SiC films is investigated using grazing-angle incidence x-ray diffraction (GIXRD), transmission electron microscopy (TEM) and Raman spectroscopy. Irradiation with 5 MeV Xe to fluence of 115 Xe/nm2 at 700 K results in a homogenous distribution of 3C-SiC grains with an average crystallite size of ~5.7 nm over the entire film thickness (~1 μm). The nucleation and growth processes exhibit a weak dependence on dose in displacements per atom (dpa) in the dose range from 6 to 20 dpa. A transformation of homonuclear C-C bonds from sp3 to sp2 hybridization is observed in themore » irradiated films, which may be partly responsible for the observed grain size saturation. The results from this study may have a significant impact on synthesis of nanograins in amorphous SiC and other similar materials with effective control of grain size and density by ion irradiation.« less

Focal brain lesions induced with ultraviolet irradiation.

PubMed

Nakata, Mariko; Nagasaka, Kazuaki; Shimoda, Masayuki; Takashima, Ichiro; Yamamoto, Shinya

2018-05-22

Lesion and inactivation methods have played important roles in neuroscience studies. However, traditional techniques for creating a brain lesion are highly invasive, and control of lesion size and shape using these techniques is not easy. Here, we developed a novel method for creating a lesion on the cortical surface via 365 nm ultraviolet (UV) irradiation without breaking the dura mater. We demonstrated that 2.0 mWh UV irradiation, but not the same amount of non-UV light irradiation, induced an inverted bell-shaped lesion with neuronal loss and accumulation of glial cells. Moreover, the volume of the UV irradiation-induced lesion depended on the UV light exposure amount. We further succeeded in visualizing the lesioned site in a living animal using magnetic resonance imaging (MRI). Importantly, we also observed using an optical imaging technique that the spread of neural activation evoked by adjacent cortical stimulation disappeared only at the UV-irradiated site. In summary, UV irradiation can induce a focal brain lesion with a stable shape and size in a less invasive manner than traditional lesioning methods. This method is applicable to not only neuroscientific lesion experiments but also studies of the focal brain injury recovery process.

Irradiance and spectral distribution control system for controlled environment chambers

NASA Technical Reports Server (NTRS)

Krones, M. J.; Sager, J. C.; Johnson, A. T.; Knott, W. M. (Principal Investigator)

1987-01-01

This paper describes a closed-loop control system for controlling the irradiance and spectral quality generated by fluorescent lamps in a controlled environment chamber. The 400 to 800 nm irradiance and the ratio of the red waveband (600 to 700 nm) to the far-red waveband (700 to 800 nm) were independently controlled and varied as functions of time. A suggested application is to investigate the possibility of synergistic effects of changing irradiance levels and changing spectral distributions on photoperiodism and photomorphogenesis.

Nitrogen-atom endohedral fullerene synthesis with high efficiency by controlling plasma-ion irradiation energy and C60 internal energy

NASA Astrophysics Data System (ADS)

Cho, Soon Cheon; Kaneko, Toshiro; Ishida, Hiroyasu; Hatakeyama, Rikizo

2015-03-01

The nitrogen-atom endohedral fullerene (N@C60) has been synthesized by controlling the plasma ion irradiation energy (Ei) and fullerene (C60) behavior in the sublimation phase. We examined the relationship between the synthesis purity of N@C60 [molar concentration ratio of N@C60 to pristine fullerene (C60)] and Ei, which was controlled by changing the substrate bias voltages (Vsub) and gas pressure (PN2) during the plasma irradiation process. High-density nitrogen-molecular ions (N2+) with a suitable Ei near 80 eV are confirmed to be the optimum condition of the nitrogen plasma for the synthesis of high-purity N@C60. In addition, high sublimation of C60 contributes to a higher yield due to the high internal energy of C60 and the related cage defects that are present under these conditions. As a result, a purity of 0.83% is realized for the first time, which is almost two orders of magnitude higher than that using other methods.

Low-intensity laser irradiation at 660 nm stimulates cytochrome c oxidase in stressed fibroblast cells.

PubMed

Houreld, Nicolette N; Masha, Roland T; Abrahamse, Heidi

2012-07-01

Low-intensity laser irradiation (LILI) has been used to modulate a variety of biological processes, including diabetic wound healing. The mechanism of action is thought to exist primarily with the mitochondria. This study aimed to determine the effect of irradiation on normal, diabetic, and ischemic mitochondrial electron transport chain (ETC) complexes. Normal, diabetic and ischemic human skin fibroblast mitochondria were irradiated in vitro at a wavelength of 660 nm and a fluence of either 5 or 15 J/cm(2). Non-irradiated mitochondria served as controls. Enzyme activities of mitochondrial complexes I, II, III, and IV were determined immediately post-irradiation. Normal, diabetic, and ischemic cells were irradiated and adenosine triphosphate (ATP) and active mitochondria were determined by luminescence and fluorescent microscopy, respectively. Irradiated diabetic mitochondria at a fluence of 15 J/cm(2) showed a significant decrease in complex III activity (P < 0.05). Normal (P < 0.01) and diabetic (P < 0.05) mitochondria irradiated at either 5 or 15 J/cm(2) showed a significant increase in complex IV activity. ATP results showed a significant increase in irradiated normal cells (5 J/cm(2); P < 0.05) and diabetic cells (15 J/cm(2); P < 0.01). There was a higher accumulation of active mitochondria in irradiated cells than non-irradiated cells. Irradiation at 660 nm has the ability to influence mitochondrial enzyme activity, in particular cytochrome c oxidase. This leads to increased mitochondrial activity and ATP synthesis. Copyright © 2012 Wiley Periodicals, Inc.

Impact of radiation processing on quality during storage and post-refrigeration decay of plum (Prunus domestica L.) cv. Santaroza

NASA Astrophysics Data System (ADS)

Hussain, Peerzada R.; Dar, Mohd A.; Wani, Ali M.

2013-04-01

Gamma irradiation treatment was tested for maintaining storage quality and extending the shelf life of plum fruit. Matured green plums were irradiated in the dose range of 0.2-1.5 kGy and stored under ambient (temperature 25±2 °C, RH 70%) and refrigerated (temperature 3±1 °C, RH 80%) conditions. Studies revealed that irradiation treatment significantly (p≤0.05) maintained the storage quality of plum fruit under ambient as well as refrigerated conditions. Positive correlations (r=0.88) existed between the irradiation doses and firmness retention under both the storage conditions. In samples irradiated at 1.0 kGy, 1.2 kGy and 1.5 kGy, no microbial load was detected up to 8 and 12 days of ambient storage. Dose range of 1.2-1.5 kGy significantly inhibited the decaying of plums up to 16 days of ambient storage. Irradiation in combination with refrigeration prevented the decaying of plums up to 35 days as against the 12.5% decay in un-irradiated control samples. Irradiation dose of 1.2-1.5 kGy also gave an extension of 8 days during additional ambient storage of the plums at 25±2 °C, RH 70% following 35 days of refrigeration.

Impacts of Irradiation Sources on Quality Attributes of Low-salt Sausage during Refrigerated Storage

PubMed Central

Kim, Hyun-Wook; Choi, Yun-Sang

2017-01-01

This study was performed to investigate the impacts of irradiation sources on quality attributes of low-salt sausage during refrigerated storage. Control sausage was prepared with 1.5% sodium chloride (NaCl), whereas low-salt sausage was formulated with 0.75% NaCl (a 50% reduction; L-control). Sausage samples were vacuum-packaged, and low-sausages were irradiated with gamma-ray, electron-beam and X-ray at 5 kGy, respectively. The samples were stored at 4°C for 28 d to determine changes in quality attributes. The pH of low-salt sausages was unaffected by irradiation at 5 kGy (p>0.05). Higher redness values were found at irradiated low-salt sausages compared to control (p<0.05). The hardness, gumminess and chewiness of control sausage were higher than those of low-salt sausages (p<0.05). However, there were no significant differences in the textural parameters between low-salt sausage treatments. The overall sensory acceptability score of irradiated/low-salt sausages were lower than L-control due to decreased scores for cooked meat flavor but increased radiolytic off-flavor (p<0.05). The initial 2-thiobarbituric acid-reactive substances (TBARS) values of irradiated/low-salt sausages were higher than control and L-control (p<0.05). However, the TBARS values of irradiated treatments were significantly lower than control at the end of storage. Irradiation could effectively inhibit the microorganism growth (total aerobic bacteria, coliforms, Enterobacteriaceae, and Pseudomonas spp.) in low-salt sausages (p<0.05). Therefore, our findings show that irradiation could be to improve microbial safety of low-salt sausages, and suggest that further studies should be necessary to reducing radiolytic off-flavor of irradiated/low-salt sausages. PMID:29147093

Biological effects of a semiconductor diode laser on human periodontal ligament fibroblasts

PubMed Central

Choi, Eun-Jeong; Yim, Ju-Young; Koo, Ki-Tae; Seol, Yang-Jo; Lee, Yong-Moo; Ku, Young; Rhyu, In-Chul; Chung, Chong-Pyoung

2010-01-01

Purpose It has been reported that low-level semiconductor diode lasers could enhance the wound healing process. The periodontal ligament is crucial for maintaining the tooth and surrounding tissues in periodontal wound healing. While low-level semiconductor diode lasers have been used in low-level laser therapy, there have been few reports on their effects on periodontal ligament fibroblasts (PDLFs). We performed this study to investigate the biological effects of semiconductor diode lasers on human PDLFs. Methods Human PDLFs were cultured and irradiated with a gallium-aluminum-arsenate (GaAlAs) semiconductor diode laser of which the wavelength was 810 nm. The power output was fixed at 500 mW in the continuous wave mode with various energy fluencies, which were 1.97, 3.94, and 5.91 J/cm2. A culture of PDLFs without laser irradiation was regarded as a control. Then, cells were additionally incubated in 72 hours for MTS assay and an alkaline phosphatase (ALPase) activity test. At 48 hours post-laser irradiation, western blot analysis was performed to determine extracellular signal-regulated kinase (ERK) activity. ANOVA was used to assess the significance level of the differences among groups (P<0.05). Results At all energy fluencies of laser irradiation, PDLFs proliferation gradually increased for 72 hours without any significant differences compared with the control over the entire period taken together. However, an increment of cell proliferation significantly greater than in the control occurred between 24 and 48 hours at laser irradiation settings of 1.97 and 3.94 J/cm2 (P<0.05). The highest ALPase activity was found at 48 and 72 hours post-laser irradiation with 3.94 J/cm2 energy fluency (P<0.05). The phosphorylated ERK level was more prominent at 3.94 J/cm2 energy fluency than in the control. Conclusions The present study demonstrated that the GaAlAs semiconductor diode laser promoted proliferation and differentiation of human PDLFs. PMID:20607054

EFFECT OF ABDOMINAL SHIELDING ON THE METABOLISM OF HYDROCORTISONE BY LIVER TISSUE OF X-IRRADIATED RATS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lott, J.R.

Liver slices removed from adult rats at various times following whole body x-irradiations of 850, 1500, and 2000 r were tested for their ability to metabolize hydrocortisone ( free alcohol). The animals were divided into a non- irradiated control group, an irradiated unshielded group, and an abdominal- shielded irradiated group. It was found that the irradiated unshielded liver slices metabo lized the hydrocortisone at a lower rate than control slices. Liver slices removed from animals whose abdominal regions were shielded during irradiation were found to metabolize hydrocortisone at a higher rate than control slices. The effects observed appeared to bemore » dependent on total dosage and time of removal of the liver post-irradiation. (auth)« less

Effects of Cell-Free Spleen Extract Treatment on the Hematopoietic Tissues of Irradiated Guinea-Pigs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ellinger, Friedrigh; Strike, Thomas A.

2004-07-01

Guinea pigs were given whole-body Co 60 irradiation (650 r) and injected daily thereafter with cell-free extracts of homologous and heterologous spleen. Spleen of irradiated control guinea pigs showed a progressive reduction of alkaline phosphatase staining commencing after the 3rd postirradiation day and reaching a maximum on or about the 9th day. Treatment of the animals with spleen extracts modified the radioinduced changes in alkaline phosphatase staining, so that an almost normal appearance was noted over the entire 14-day observation period. Most of the alkaiine phosphatase-staining spleen elements were mature neutrophils. It was concluded that spleen extract treatment affects apparentlymore » various celluiar elements of spleen in a different way. The results support the hypothesis that protection of phosphorylization processes against effects of irradiation represent one of the mechanisms by which the radiation protective effect of spleen extracts is effected.« less

635nm diode laser biostimulation on cutaneous wounds

NASA Astrophysics Data System (ADS)

Solmaz, Hakan; Gülsoy, Murat; Ülgen, Yekta

2014-05-01

Biostimulation is still a controversial subject in wound healing studies. The effect of laser depends of not only laser parameters applied but also the physiological state of the target tissue. The aim of this project is to investigate the biostimulation effects of 635nm laser irradiation on the healing processes of cutaneous wounds by means of morphological and histological examinations. 3-4 months old male Wistar Albino rats weighing 330 to 350 gr were used throughout this study. Low-level laser therapy was applied through local irradiation of red light on open skin excision wounds of 5mm in diameter prepared via punch biopsy. Each animal had three identical wounds on their right dorsal part, at which two of them were irradiated with continuous diode laser of 635nm in wavelength, 30mW of power output and two different energy densities of 1 J/cm2 and 3 J/cm2. The third wound was kept as control group and had no irradiation. In order to find out the biostimulation consequences during each step of wound healing, which are inflammation, proliferation and remodeling, wound tissues removed at days 3, 7, 10 and 14 following the laser irradiation are morphologically examined and than prepared for histological examination. Fragments of skin including the margin and neighboring healthy tissue were embedded in paraffin and 6 to 9 um thick sections cut are stained with hematoxylin and eosin. Histological examinations show that 635nm laser irradiation accelerated the healing process of cutaneous wounds while considering the changes of tissue morphology, inflammatory reaction, proliferation of newly formed fibroblasts and formation and deposition of collagen fibers. The data obtained gives rise to examine the effects of two distinct power densities of low-level laser irradiation and compare both with the non-treatment groups at different stages of healing process.

Hydrothermal microwave processing of microalgae as a pre-treatment and extraction technique for bio-fuels and bio-products.

PubMed

Biller, Patrick; Friedman, Cerri; Ross, Andrew B

2013-05-01

Microalgae are regarded as a promising source of lipids for bio-diesel production and bio-products. The current paper investigates the processing of microalgal slurries under controlled microwave irradiation. Microwave power was applied to reach temperatures of 80, 100, 120 and 140 °C at a constant residence time of 12 min. Microwave irradiation led to disruption of the algal cell walls which facilitated lipid extraction. The influence of inorganic material on microwave heating was assessed for three strains including, Nannochloropsis occulata, Chlorogloeopsis fritschii and Pseudochoricystis ellipsoidea. Mass balances were calculated and showed that the amount of carbon, nitrogen and total mass recovered in the residue was highly dependent on process conditions and algae strain. Hydrothermal microwave processing (HMP) was found to be an effective pre-treatment for hydrothermal liquefaction and extraction of lipids and phytochemicals. Copyright © 2013 Elsevier Ltd. All rights reserved.

Inactivation of Aspergillus flavus in drinking water after treatment with UV irradiation followed by chlorination.

PubMed

Al-Gabr, Hamid Mohammad; Zheng, Tianling; Yu, Xin

2013-10-01

The disinfection process for inactivating microorganisms at drinking water treatment plants is aimed for safety of drinking water for humans from a microorganism, such as bacteria, viruses, algae, fungi by using chlorination, ozonation, UV irradiation, etc. In the present study, a combination of two disinfectants, UV irradiation followed by chlorination, was evaluated for inactivating Aspergillus flavus under low contact time and low dosage of UV irradiation. The results indicated an inverse correlation between the inactivation of A. flavus by using UV irradiation only or chlorination alone. By using UV radiation, the 2 log10 control of A. flavus was achieved after 30 s of irradiation, while chlorination was observed to be more effective than UV, where the 2 log was achieved at chlorine concentration of 0.5, 1, 2 and 3 mg/l, in contact time of 60, 5, 1 and 1 min, respectively. However, combined use (UV irradiation followed by chlorination) was more effective than using either UV or chlorination alone; 5 s UV irradiation followed by chlorination produced 4 log10 reduction of A. flavus at chlorine concentrations of 2 and 3 mg/l under a contact time of 15 min. The results indicated that efficiency of UV irradiation improves when followed by chlorination at low concentrations. Copyright © 2013 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simone, Brittany A.; Ly, David; Savage, Jason E.

Purpose: Although ionizing radiation is critical in treating cancer, radiation-induced fibrosis (RIF) can have a devastating impact on patients' quality of life. The molecular changes leading to radiation-induced fibrosis must be elucidated so that novel treatments can be designed. Methods and Materials: To determine whether microRNAs (miRs) could be responsible for RIF, the fibrotic process was induced in the right hind legs of 9-week old CH3 mice by a single-fraction dose of irradiation to 35 Gy, and the left leg served as an unirradiated control. Fibrosis was quantified by measurements of leg length compared with control leg length. By 120 days aftermore » irradiation, the irradiated legs were 20% (P=.013) shorter on average than were the control legs. Results: Tissue analysis was done on muscle, skin, and subcutaneous tissue from irradiated and control legs. Fibrosis was noted on both gross and histologic examination by use of a pentachrome stain. Microarrays were performed at various times after irradiation, including 7 days, 14 days, 50 days, 90 days, and 120 days after irradiation. miR-15a, miR-21, miR-30a, and miR-34a were the miRs with the most significant alteration by array with miR-34a, proving most significant on confirmation by reverse transcriptase polymerase chain reaction, c-Met, a known effector of fibrosis and downstream molecule of miR-34a, was evaluated by use of 2 cell lines: HCT116 and 1522. The cell lines were exposed to various stressors to induce miR changes, specifically ionizing radiation. Additionally, in vitro transfections with pre-miRs and anti-miRs confirmed the relationship of miR-34a and c-Met. Conclusions: Our data demonstrate an inverse relationship with miR-34a and c-Met; the upregulation of miR-34a in RIF causes inhibition of c-Met production. miRs may play a role in RIF; in particular, miR-34a should be investigated as a potential target to prevent or treat this devastating side effect of irradiation.« less

microRNA alterations driving acute and late stages of radiation-induced fibrosis in a murine skin model.

PubMed

Simone, Brittany A; Ly, David; Savage, Jason E; Hewitt, Stephen M; Dan, Tu D; Ylaya, Kris; Shankavaram, Uma; Lim, Meng; Jin, Lianjin; Camphausen, Kevin; Mitchell, James B; Simone, Nicole L

2014-09-01

Although ionizing radiation is critical in treating cancer, radiation-induced fibrosis (RIF) can have a devastating impact on patients' quality of life. The molecular changes leading to radiation-induced fibrosis must be elucidated so that novel treatments can be designed. To determine whether microRNAs (miRs) could be responsible for RIF, the fibrotic process was induced in the right hind legs of 9-week old CH3 mice by a single-fraction dose of irradiation to 35 Gy, and the left leg served as an unirradiated control. Fibrosis was quantified by measurements of leg length compared with control leg length. By 120 days after irradiation, the irradiated legs were 20% (P=.013) shorter on average than were the control legs. Tissue analysis was done on muscle, skin, and subcutaneous tissue from irradiated and control legs. Fibrosis was noted on both gross and histologic examination by use of a pentachrome stain. Microarrays were performed at various times after irradiation, including 7 days, 14 days, 50 days, 90 days, and 120 days after irradiation. miR-15a, miR-21, miR-30a, and miR-34a were the miRs with the most significant alteration by array with miR-34a, proving most significant on confirmation by reverse transcriptase polymerase chain reaction, c-Met, a known effector of fibrosis and downstream molecule of miR-34a, was evaluated by use of 2 cell lines: HCT116 and 1522. The cell lines were exposed to various stressors to induce miR changes, specifically ionizing radiation. Additionally, in vitro transfections with pre-miRs and anti-miRs confirmed the relationship of miR-34a and c-Met. Our data demonstrate an inverse relationship with miR-34a and c-Met; the upregulation of miR-34a in RIF causes inhibition of c-Met production. miRs may play a role in RIF; in particular, miR-34a should be investigated as a potential target to prevent or treat this devastating side effect of irradiation. Published by Elsevier Inc.

The Alliance of Advanced Process Control and Accountability – A Future Safeguards-By-Design Tool

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lumetta, Gregg J.; Bresee, James C.; Paviet, Patricia D.

For any chemical separation process producing a valuable product, a material balance is an important process control measurement. That is particularly true for the separation of actinides from irradiated nuclear fuel, not only for their intrinsic value but also because an incomplete material balance may indicate diversion for unauthorized use. The DOE Office of Nuclear Energy is currently carrying out at the Pacific Northwest National Laboratory an experimental measurement of how well and with what precision current technologies can implement near real-time actinide material balances. This measurement effort is called the CoDCon project. It involves the separation of a productmore » with a 70/30 uranium/plutonium mass ratio. Initial tests will use dissolved fuel simulants prepared with pure uranium and plutonium nitrates at the same input ratios as irradiated fuel. Subsequent testing with actual irradiated fuel would be done to verify the results obtained with simulants. The experiments will use advanced on-line instrumentation supported by dynamic process models. Since accountability uncertainties could mask diversions, the aim of the project is not only to measure present-day capabilities but also, through sensitivity analyses, to identify those measurements with the greatest potential for overall material-balance improvements. The latter results will help identify priorities for future fuel cycle R&D programs. Advanced separations process control and material accountability technologies thus have a common goal: to provide the best tools available for safeguards-by-design [defined by the International Atomic Energy Agency (IAEA) as the integration of the design of a new nuclear facility through planning, construction, operation and decommissioning]. Since the potential domestic use of CoDCon results may be later than their possible foreign applications, arrangements may be feasible for possible bilateral or multinational cooperation in the CoDCon project.« less

Pulsed photoinitiated fabrication of inkjet printed titanium dioxide/reduced graphene oxide nanocomposite thin films.

PubMed

Bourgeois, Briley; Luo, Sijun; Riggs, Brian; Ji, Yaping; Adireddy, Shiva; Schroder, Kurt; Farnsworth, Stan; Chrisey, Douglas; Escarra, Matthew

2018-08-03

This work reports a new technique for scalable and low-temperature processing of nanostructured TiO 2 thin films, allowing for practical manufacturing of TiO 2 -based devices such as perovskite solar cells at low-temperature or on flexible substrates. Dual layers of dense and mesoporous TiO 2 /graphitic oxide nanocomposite films are synthesized simultaneously using inkjet printing and pulsed photonic irradiation. Investigation of process parameters including precursor concentration (10-20 wt%) and exposure fluence (4.5-8.5 J cm -2 ) reveals control over crystalline quality, graphitic oxide phase, film thickness, dendrite density, and optical properties. Raman spectroscopy shows the E g peak, characteristic of anatase phase titania, increases in intensity with higher photonic irradiation fluence, suggesting increased crystallinity through higher fluence processing. Film thickness and dendrite density is shown to increase with precursor concentration in the printed ink. The dense base layer thickness was controlled between 20 and 80 nm. The refractive index of the films is determined by ellipsometry to be 1.92 ± 0.08 at 650 nm. Films exhibit an energy weighted optical transparency of 91.1%, in comparison to 91.3% of a thermally processed film, when in situ carbon materials were removed. Transmission and diffuse reflectance are used to determine optical band gaps of the films ranging from 2.98 to 3.38 eV in accordance with the photonic irradiation fluence and suggests tunability of TiO 2 phase composition. The sheet resistance of the synthesized films is measured to be 14.54 ± 1.11 Ω/□ and 28.90 ± 2.24 Ω/□ for films as-processed and after carbon removal, respectively, which is comparable to high temperature processed TiO 2 thin films. The studied electrical and optical properties of the light processed films show comparable results to traditionally processed TiO 2 while offering the distinct advantages of scalable manufacturing, low-temperature processing, simultaneous bilayer fabrication, and in situ formation of removable carbon nanocomposites.

Laser synthesized super-hydrophobic conducting carbon with broccoli-type morphology as a counter-electrode for dye sensitized solar cells

NASA Astrophysics Data System (ADS)

Gokhale, Rohan; Agarkar, Shruti; Debgupta, Joyashish; Shinde, Deodatta; Lefez, Benoit; Banerjee, Abhik; Jog, Jyoti; More, Mahendra; Hannoyer, Beatrice; Ogale, Satishchandra

2012-10-01

A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode.A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode. Electronic supplementary information (ESI) available: Materials and equipment details, solar cell fabrication protocol, electrolyte spreading time measurement details, XPS spectra, electronic study, film adhesion test detailed analysis and field emission results. See DOI: 10.1039/c2nr32082g

76 FR 20509 - Irradiation in the Production, Processing, and Handling of Food

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

.... FDA-1998-F-0072] (Formerly 98F-0165) Irradiation in the Production, Processing, and Handling of Food..., Irradiation in the Production, Processing, and Handling of Food (21 CFR part 179), to provide for the safe use... irradiation of fresh shell eggs for the reduction of Salmonella at doses not to exceed 3.0 kiloGray (kGy...

Effect of radiation processing on antinutrients, in-vitro protein digestibility and protein efficiency ratio bioassay of legume seeds

NASA Astrophysics Data System (ADS)

El-Niely, Hania F. G.

2007-06-01

The effects of irradiation (dose levels of 5, 7.5 and 10 kGy) on nutritive characteristics of peas ( Pisum satinum L), cowpeas ( Vigna unguiculata L.Walp), lentils ( Lens culinaris Med), kidneybeans ( Phaseolus vulgaris L), and chickpeas ( Cicer arietinum L) were examined. Analyses included proximate composition, levels of anti-nutrients (phytic acid, tannins), available lysine (AL), in vitro protein digestibility (IVPD), and protein efficiency ratio (PER) in the growing rat. The results showed that moisture, crude protein, crude fat, crude fiber, and ash were unchanged by the irradiation. Radiation processing significantly ( p<0.05) reduced the levels of phytic acid (PA), tannins (TN), and AL. IVPD and PER were significantly enhanced in a dose-dependent manner, relative to unirradiated control samples, for all legumes. The data sets for each legume exhibited high correlation coefficients between radiation dose and PA, TN, AL, IVPD, and PER. These results demonstrate the benefits of irradiation on the nutritional properties of these legumes.

Unusual Attenuation Recovery Process After Fiber Optic Cable Irradiation

NASA Astrophysics Data System (ADS)

Konečná, Z.; Plaček, V.; Havránek, P.

2017-11-01

At present, the number of optical cables in nuclear power plants has been increasing. Fiber optic cables are commonly used at nuclear power plants in instrumentation and control systems but they are usually used in environments without radiation. Nevertheless, currently, the number of applications in NPP containment with radiation is increasing. One of the most prevalent effects of radiation exposure is an increase of signal attenuation (signal loss). This is the result of fiber darkening due to radiation exposure and it is the main limitation factor in application of fiber optics in radiation environment. However, after the irradiation, the fiber optics go through a “recovery process” during which the optical properties improve again; i.e. attenuation decreases. However, we have found cable, where the expected healing process after few days changed its trend and the attenuation increased again to a value well above the attenuation just after the irradiation. This paper describes experiments that were carried out to explain this unusual recovery behaviour.

Identification of differentially expressed proteins in Ostrinia furnacalis adults after exposure to ultraviolet A.

PubMed

Zhang, Changyu; Meng, Jianyu

2018-06-23

Ultraviolet A (UVA), the major component of solar UV irradiation, is an important environmental factor inducing damage to insects including cell death, photoreceptor damage, and oxidative stress. In order to improve understanding of the adaptation mechanisms of insect after UVA exposure, a comparative proteomic analysis was carried out to reveal differential protein expression in Ostrinia furnacalis. Three-day-old adults were treated with UVA for 1 h. Total proteins of control and UVA-treated insects were examined using two-dimensional electrophoresis (2-DE). 2-DE analysis demonstrated that 19 proteins were increased and 18 proteins were decreased significantly in O. furnacalis after UVA exposure, respectively. Thirty differentially expressed proteins were successfully identified by mass spectrometry. The identified proteins were involved in diverse biological processes, such as signal transduction, transport processing, cellular stress, metabolisms, and cytoskeleton organization. Our results reveal that the response patterns of O. furnacalis to UVA irradiation are complex and provide novel insights into the adaptation response to UVA irradiation stress.

Performance and applications of the 14 MEV electron radiation linac at CIAE

NASA Astrophysics Data System (ADS)

Zhai, X. L.; Chen, G. C.; Qi, B. M.; Xu, F. J.; Pan, L. H.; Zhang, Z. M.; Shi, X. Z.; Chen, J. K.; Wang, F. Y.

1993-07-01

A 14 MeV electron linear accelerator which was designed and manufactured by the China Institute of Atomic Energy (CIAE) has been modified into an radiation processing accelerator in 1987. It consists of an electron gun, two prebunchers, one buncher, a three meter long accelerating section, and a 90 degree bending magnet. The linac is S-band (2856 MHz), travelling wave accelerator driven by a Chinese-made klystron. The energy of electrons can be adjusted from 8 MeV to 18 MeV and the average beam power is about 2 kW. The beam width is 600 mm and the uniformity of scanning beam is better than 10%. The linac is used to irradiate power semiconductor devices for controlling the minority carrier lifetime (MCL). More than twenty factories and scientific institutions use this linac to irradiate silicon controlled rectifiers (SCR) and the fast recovery diodes (FRD), and more than 0.2 million pieces of SCR have been irradiated. Tests have also been carried out for colour-change of topaz.

AGR-2 and AGR-3/4 Release-to-Birth Ratio Data Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pham, Binh T.; Einerson, Jeffrey J.; Scates, Dawn M.

A series of Advanced Gas Reactor (AGR) irradiation tests is being conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tristructural isotropic (TRISO) low enriched fuel used in the High Temperature Gas-cooled Reactor (HTGR). Each AGR test consists of multiple independently controlled and monitored capsules containing fuel compacts placed in a graphite cylinder shrouded by a steel shell. These capsules are instrumented with thermocouples embedded in the graphite enabling temperature control. AGR configuration and irradiation conditions are based on prismatic HTGR technology that is distinguished primarily through use of heliummore » coolant, a low-power-density ceramic core capable of withstanding very high temperatures, and TRISO coated particle fuel. Thus, these tests provide valuable irradiation performance data to support fuel process development, qualify fuel for normal operating conditions, and support development and validation of fuel performance and fission product transport models and codes.« less

Revealing ionization-induced dynamic recovery in ion-irradiated SrTiO 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Velisa, Gihan; Wendler, Elke; Xue, Haizhou

The lack of fundamental understanding on the coupled effects of energy deposition to electrons and atomic nuclei on defect processes and irradiation response poses a significant roadblock for the design and control of material properties. In this work, SrTiO 3 has been irradiated with various ion species over a wide range of ion fluences at room temperature with a goal to deposit different amounts of energy to target electrons and atomic nuclei by varying the ratio of electronic to nuclear energy loss. Here, the results unambiguously show a dramatic difference in behavior of SrTiO 3 irradiated with light ions (Ne,more » O) compared to heavy ions (Ar). While the damage accumulation and amorphization under Ar ion irradiation are consistent with previous observations and existing models, the damage accumulation under Ne irradiation reveals a quasi-saturation state at a fractional disorder of 0.54 at the damage peak for an ion fluence corresponding to a dose of 0.5 dpa; this is followed by further increases in disorder with increasing ion fluence. In the case of O ion irradiation, the damage accumulation at the damage peak closely follows that for Ne ion irradiation up to a fluence corresponding to a dose of 0.5 dpa, where a quasi-saturation of fractional disorder level occurs at about 0.48; however, in this case, the disorder at the damage peak decreases slightly with further increases in fluence. This behavior is associated with changes in kinetics due to irradiation-enhanced diffusional processes that are dependent on electronic energy loss and the ratio of electronic to nuclear energy dissipation. Lastly, these findings are critical for advancing the fundamental understanding of ion-solid interactions and for a large number of applications in oxide electronics where SrTiO 3 is a foundational material.« less

Identification of isomers and control of ionization and dissociation processes using dual-mass-spectrometer scheme and genetic algorithm optimization

NASA Astrophysics Data System (ADS)

Chen, Zhou; Tong, Qiu-Nan; Zhang, Cong-Cong; Hu, Zhan

2015-04-01

Identification of acetone and its two isomers, and the control of their ionization and dissociation processes are performed using a dual-mass-spectrometer scheme. The scheme employs two sets of time of flight mass spectrometers to simultaneously acquire the mass spectra of two different molecules under the irradiation of identically shaped femtosecond laser pulses. The optimal laser pulses are found using closed-loop learning method based on a genetic algorithm. Compared with the mass spectra of the two isomers that are obtained with the transform limited pulse, those obtained under the irradiation of the optimal laser pulse show large differences and the various reaction pathways of the two molecules are selectively controlled. The experimental results demonstrate that the scheme is quite effective and useful in studies of two molecules having common mass peaks, which makes a traditional single mass spectrometer unfeasible. Project supported by the National Basic Research Program of China (Grant No. 2013CB922200) and the National Natural Science Foundation of China (Grant No. 11374124).

Address substrates as promising targets for laser histochemical surgery as a nontraditional line in medicine

NASA Astrophysics Data System (ADS)

Piruzyan, L. A.; Mikhailovskiy, Ye. M.; Piruzyan, A. L.

1999-12-01

The priority concept of the laser histochemical surgery as a potentially novel line in medicine is presented. The histochemical stains, selectively coloring some targets (address substrates), that are cells or their biochemical ingredients, sensitize them to the laser irradiation. Such sensitization to laser irradiation by staining turns the colored targets into targets for the laser beam. The action of the irradiation onto its specific targets beats out of the cell its ingredients which participate in a pathology process. In particular, the beating of a stained ferment out of the general stage of biochemical processes characteristic for the pathology interrupts their currence. The laser beam, when beating out its stained targets without any damage of the unstained tissues, acts like a scalpel that cuts off affected tissues not brushing healthy ones. A scheme for testing stains as sensitizers of the `address substrates' to the laser irradiation is presented. As the criterion of the stain sensitization the fact was chosen of absence or weakness of pathomorphologic and biochemical signs of the disease in an experimental model of the pathology irradiated with laser after a stain use, while the pathology signs are present in a control sample. The basis is done for study of the histochemical stains as potential means for the laser histochemical surgery of disseminated sclerosis, mucopolysaccharidosis, hypercholesterolemia, myocardial infarction, cardiosclerosis, caries and parodontosis.

Low Dose Irradiation of Fresh and Fresh-Cut Produce

USDA-ARS?s Scientific Manuscript database

Foodborne illness (FBI) outbreaks in the United States associated with contaminated fruits, vegetables, salads, and juices have prompted redoubled efforts to improve agricultural, post-harvest and supply-chain controls that reduce risk. However, the lack of a broadly applicable antimicrobial process...

The Rhythm of Oxidization Processes and its Disturbance Under the Action of Radiation; RITMIKA OKISLITEL'-NYKH PROTSESSOV I EE NARUSHENIE PRI DEISTVII RADIATSII

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frank, G.M.; Snezhko, A.D.

1961-08-28

A modified polarographic method has been developed to determine continuously variations in the oxygen content of tissue by inserting a platinum needle as an electrode directly into the tissue of a living animal. The''oxygen test," in which the animal is allowed to breathe a controlled amount of pure oxygen, gives information about the rate of utilization of oxygen by the tissue. Ordinarily the increase in the oxygen diffusion current DELTA I is stable in form and amplitude for any given experimental animal and for a given location of the electrode. Thus, after a total irradiation of 700 to 1000 r,more » the value of DELTA I increased by a factor of two. A decrease in the ability of tissue to utilize oxygen after irradiation is indicated. Local irradiation gives a low value of DELTA I, and indicates that the unirradiated cells utilize oxygen at a faster rate than before irradiation. The oxygen content of the tissue was observed to vary rhythmically with two periods. One rhythm had a small amplitude and a high frequency of 15 to 20 oscillations per minute, and the other rhythm had a large amplitude and a low frequency of 2 to 3 oscillations per minute. Irradiation leads to a suppression of this rhythmic oscillation in the oxygen content of the tissue. These effects are most readily apparent in the irradiation of growing rootlets (Vicia fabia) and of a multiplying yeast culture. This method sheds some light on the course of chemical processes such as oxidation that occur in the cell as a function of the period of time after irradiation. (TTT)« less

Effects of low level laser in the morphology of the skeletal muscle fiber during compensatory hypertrophy in plantar muscle of rats

NASA Astrophysics Data System (ADS)

Terena, Stella Maris Lins; Fernandes, Kristianne Porta Santos; Kalil, Sandra; Alves, Agnelo Neves; Mesquita Ferrari, Raquel Agnelli

2015-06-01

The hypertrophy is known as an increase the cross-sectional area of the muscle as a result of a muscular work against an overload, and it is compensatory because the overload is induced by functional elimination of synergistic muscles. The importance of study the compensatory hypertrophy is understand how this process can be influenced by the irradiation with regard to the weight and muscle cross-sectional area, to assist in the rehabilitation process and the effectiveness functional return. The aim was evaluate the effects of low-level laser irradiation on morphological aspects of muscle tissue, comparing the weight and cross-sectional area in rat skeletal muscle. Wistar rats were divided into three groups: control, hypertrophy group without irradiation (right plantar muscle) and hypertrophy group and irradiation (left plantar muscle), both analyzed after 7 and 14 days. The irradiation was performed daily immediately after the surgery. The parameters were: λ = 780nm, beam spot of 0.04 cm2, output power of 40mW, power density of 1W/cm2, energy density of 10J / cm2 and 10s exposure time with a total energy of 3.2 J. The results revealed that low level laser irradiation an increase the weight of the plantaris muscle after 7 and 14 days with a difference of 7.06% and 11.51% respectively. In conclusion, low level laser irradiation has an effect on compensatory hypertrophy to produce increased muscle weight and promoted an increase in cross-sectional area of muscle fibers in the compensatory hypertrophy model after 14 days with parameters cited above.

Irradiance optimization of outdoor microalgal cultures using solar tracked photobioreactors.

PubMed

Hindersin, Stefan; Leupold, Marco; Kerner, Martin; Hanelt, Dieter

2013-03-01

Photosynthetic activity and temperature regulation of microalgal cultures (Chlorella vulgaris and Scenedesmus obliquus) under different irradiances controlled by a solar tracker and different cell densities were studied in outdoor flat panel photobioreactors. An automated process control unit regulated light and temperature as well as pH value and nutrient concentration in the culture medium. CO2 was supplied using flue gas from an attached combined block heat and power station. Photosynthetic activity was determined by pulse amplitude modulation fluorometry. Compared to the horizontal irradiance of 55 mol photons m(-2) d(-1) on a clear day, the solar tracked photobioreactors enabled a decrease and increase in the overall light absorption from 19 mol photons m(-2) d(-1) (by rotation out of direct irradiance) to 79 mol photons m(-2) d(-1) (following the position of the sun). At biomass concentrations below 1.1 g cell dry weight (CDW) L(-1), photoinhibition of about 35 % occurred at irradiances of ≥1,000 μmol photons m(-2) s(-1) photosynthetic active radiation (PAR). Using solar tracked photobioreactors, photoinhibition can be reduced and at optimum biomass concentration (≥2.3 g CDW L(-1)), the culture was irradiated up to 2,000 μmol photons m(-2) s(-1) to overcome light limitation with biomass yields of 0.7 g CDW mol photons(-1) and high photosynthetic activities indicated by an effective quantum yield of 0.68 and a maximum quantum yield of 0.80 (F v/F m). Overheating due to high irradiance was avoided by turning the PBR out of the sun or using a cooling system, which maintained the temperature close to the species-specific temperature optima.

Isoconversional approach for non-isothermal decomposition of un-irradiated and photon-irradiated 5-fluorouracil.

PubMed

Mohamed, Hala Sh; Dahy, AbdelRahman A; Mahfouz, Refaat M

2017-10-25

Kinetic analysis for the non-isothermal decomposition of un-irradiated and photon-beam-irradiated 5-fluorouracil (5-FU) as anti-cancer drug, was carried out in static air. Thermal decomposition of 5-FU proceeds in two steps. One minor step in the temperature range of (270-283°C) followed by the major step in the temperature range of (285-360°C). The non-isothermal data for un-irradiated and photon-irradiated 5-FU were analyzed using linear (Tang) and non-linear (Vyazovkin) isoconversional methods. The results of the application of these free models on the present kinetic data showed quite a dependence of the activation energy on the extent of conversion. For un-irradiated 5-FU, the non-isothermal data analysis indicates that the decomposition is generally described by A3 and A4 modeles for the minor and major decomposition steps, respectively. For a photon-irradiated sample of 5-FU with total absorbed dose of 10Gy, the decomposition is controlled by A2 model throughout the coversion range. The activation energies calculated in case of photon-irradiated 5-FU were found to be lower compared to the values obtained from the thermal decomposition of the un-irradiated sample probably due to the formation of additional nucleation sites created by a photon-irradiation. The decomposition path was investigated by intrinsic reaction coordinate (IRC) at the B3LYP/6-311++G(d,p) level of DFT. Two transition states were involved in the process by homolytic rupture of NH bond and ring secession, respectively. Published by Elsevier B.V.

Effects of gamma irradiation on the radiation-resistant bacteria and polyphenol oxidase activity in fresh kale juice

NASA Astrophysics Data System (ADS)

Kim, Dongho; Song, Hyunpa; Lim, Sangyong; Yun, Hyejeong; Chung, Jinwoo

2007-07-01

Gamma radiation was performed to prolong the shelf life of natural kale juice. The total aerobic bacteria in fresh kale juice, prepared by a general kitchen process, was detected in the range of 10 6 cfu/ml, and about 10 2 cfu/ml of the bacteria survived in the juice in spite of gamma irradiation treatment with a dose of 5 kGy. Two typical radiation-resistant bacteria, Bacillus megaterium and Exiguobacterium acetylicum were isolated and identified from the 5 kGy-irradiated kale juices. The D10 values of the vegetative cell and endospore of the B. megaterium in peptone water were 0.63±0.05 and 1.52±0.05 kGy, respectively. The D10 value of the E. acetylicum was calculated as 0.65±0.06 kGy. In the inoculation test, the growth of the surviving B. megaterium and E. acetylicum in the 3-5 kGy-irradiated kale juice retarded and/or decreased significantly during a 3 d post-irradiation storage period. However, there were no significant differences in the residual polyphenol oxidase activity and browning index between the nonirradiated control and the gamma irradiated kale juice during a post-irradiation period.

A novel green approach for reduction of free standing graphene oxide: electrical and electronic structural investigations.

PubMed

Saravanan, K; Panigrahi, B K; Suresh, K; Sundaravel, B; Magudapathy, P; Gupta, Mukul

2018-08-24

Ion beam irradiation technique has been proposed, for efficient, fast and eco-friendly reduction of graphene oxide (GO), as an alternative to the conventional methods. 5 MeV, Au + ion beam has been used to reduce the free standing GO flake. Both electronic and nuclear energy loss mechanisms of the irradiation process play a major role in removal of oxygen moieties and recovery of graphene network. Atomic resolution scanning tunnelling microscopy analysis of the irradiated GO flake shows the characteristic honeycomb structure of graphene. X-ray absorption near edge structure analysis at C K-edge reveals that the features of the irradiated GO flake resemble the few layer graphene. Resonant Rutherford backscattering spectrometry analysis evidenced an enhanced C/O ratio of ∼23 in the irradiated GO. In situ sheet resistance measurements exhibit a sharp decrease of resistance (few 100 s of Ω) at a fluence of 6.5 × 10 14 ions cm -2 . Photoluminescence spectroscopic analysis of irradiated GO shows a sharp blue emission, while pristine GO exhibits a broad emission in the visible-near IR region. Region selective reduction, tunable electrical and optical properties by controlling C/O ratio makes ion irradiation as a versatile tool for the green reduction of GO for diverse applications.

Neutron-irradiation creep of silicon carbide materials beyond the initial transient

DOE PAGES

Katoh, Yutai; Ozawa, Kazumi; Shimoda, Kazuya; ...

2016-06-04

Irradiation creep beyond the transient regime was investigated for various silicon carbide (SiC) materials. Here, the materials examined included polycrystalline or monocrystalline high-purity SiC, nanopowder sintered SiC, highly crystalline and near-stoichiometric SiC fibers (including Hi-Nicalon Type S, Tyranno SA3, isotopically-controlled Sylramic and Sylramic-iBN fibers), and a Tyranno SA3 fiber–reinforced SiC matrix composite fabricated through a nano-infiltration transient eutectic phase process. Neutron irradiation experiments for bend stress relaxation tests were conducted at irradiation temperatures ranging from 430 to 1180 °C up to 30 dpa with initial bend stresses of up to ~1 GPa for the fibers and ~300 MPa for themore » other materials. Initial bend stress in the specimens continued to decrease from 1 to 30 dpa. Analysis revealed that (1) the stress exponent of irradiation creep above 1 dpa is approximately unity, (2) the stress normalized creep rate is ~1 × 10 –7 [dpa –1 MPa –1] at 430–750 °C for the range of 1–30 dpa for most polycrystalline SiC materials, and (3) the effects on irradiation creep of initial microstructures—such as grain boundary, crystal orientation, and secondary phases—increase with increasing irradiation temperature.« less

Decomposition and biodegradability enhancement of textile wastewater using a combination of electron beam irradiation and activated sludge process.

PubMed

Mohd Nasir, Norlirubayah; Teo Ming, Ting; Ahmadun, Fakhru'l-Razi; Sobri, Shafreeza

2010-01-01

The research conducted a study on decomposition and biodegradability enhancement of textile wastewater using a combination of electron beam irradiation and activated sludge process. The purposes of this research are to remove pollutant through decomposition and to enhance the biodegradability of textile wastewater. The wastewater is treated using electron beam irradiation as a pre-treatment before undergo an activated sludge process. As a result, for non-irradiated wastewater, the COD removal was achieved to be between 70% and 79% after activated sludge process. The improvement of COD removal efficiency increased to 94% after irradiation of treated effluent at the dose of 50 kGy. Meanwhile, the BOD(5) removal efficiencies of non-irradiated and irradiated textile wastewater were reported to be between 80 and 87%, and 82 and 99.2%, respectively. The maximum BOD(5) removal efficiency was achieved at day 1 (HRT 5 days) of the process of an irradiated textile wastewater which is 99.2%. The biodegradability ratio of non-irradiated wastewater was reported to be between 0.34 and 0.61, while the value of biodegradability ratio of an irradiated wastewater increased to be between 0.87 and 0.96. The biodegradability enhancement of textile wastewater is increased with increasing the doses. Therefore, an electron beam radiation holds a greatest application of removing pollutants and also on enhancing the biodegradability of textile wastewater.

Degradation of triclosan and its main intermediates during the combined irradiation and biological treatment.

PubMed

Wang, Shizong; Wang, Jianlong

2018-05-01

Triclosan is an extensively applied antimicrobial agent which has been frequently detected in the environment. In this paper, the degradation of triclosan and its main intermediates was investigated during the combined irradiation and biological treatment. The results showed that triclosan degradation increased with increase of absorbed dose, the removal efficiency of triclosan was 62%, 77%, 87%, 91% and 94%, respectively at 1, 2, 3, 4 and 5 kGy. The final removal efficiency of triclosan after the combined irradiation and biological process was 81%, 86%, 90%, 92% and 95%, respectively. During the irradiation process, two main intermediates, that is, 4,4'-2'-phenoxyphenol (Intermediate 1) and 4-chloro-2'-phenoxyphenol (Intermediate 2) were detected, in which Intermediate 1 dominated during the irradiation process. In the following biological treatment process, Intermediates 1 and 2 could be further degraded. In single biological treatment process, the final removal efficiency of triclosan was 54%, and Intermediates 1 and 2 were detected. Intermediate 1 could be biodegraded while Intermediate 2 could not. The concentration of Intermediate 2 increased during biological treatment process. In conclusion, irradiation as pre-treatment process can enhance the degradation of triclosan and improve the biodegradability of Intermediate 2. Combined irradiation and biological process can be promising for treating antibiotic-containing wastewater.

A study of hydrogen peroxide chemistry and photochemistry in tea stain solution with relevance to clinical tooth whitening.

PubMed

Young, Nigel; Fairley, Peter; Mohan, Veena; Jumeaux, Coline

2012-12-01

Tooth whitening using hydrogen peroxide is a complex process, and there is still some controversy about the roles of pH, temperature, chemical activators, and the use of light irradiation. In this work the basic interactions between whitening agents and stain molecules are studied in simple solutions, thus avoiding the physics of diffusion and light penetration in the tooth to give clarity on the basic chemistry which is occurring. The absorbance of tea stain solution at 450 nm was measured over a period of 40 min, with various compositions of whitening agent added (including hydrogen peroxide, ferrous gluconate and potassium hydroxide) and at the same time the samples were subjected to blue light (465 nm) or infra-red light (850 nm) irradiation, or alternatively they were heated to 37°C. It is shown that the reaction rates between chromogens in the tea solution and hydrogen peroxide can be accelerated significantly using ferrous gluconate activator and blue light irradiation. Infra red irradiation does not increase the reaction rate through photochemistry, it serves only to increase the temperature. Raising the temperature leads to inefficiency through the acceleration of exothermic decomposition reactions which produce only water and oxygen. By carrying out work in simple solution it was possible to show that ferrous activators and blue light irradiation significantly enhance the whitening process, whereas infra red irradiation has no significant effect over heating. The importance of controlling the pH within the tooth structure during whitening is also demonstrated. Copyright © 2012 Elsevier Ltd. All rights reserved.

Food irradiation in the United States: irradiation as a phytosanitary treatment for fresh fruits and vegetables and for the control of microorganisms in meat and poultry

NASA Astrophysics Data System (ADS)

Ross, Ralph T.; Engeljohn, Dan

2000-03-01

Recently there has been a renewed focus on food irradiation in the United States (US) for the disinfestation of fresh fruits and vegetables to eliminate pests from imported agricultural commodities that could threaten the economic viability of American agriculture and for the control of bacterium E. coli 0157:H7 in beef, a pathogen that threatens the safety of the US domestic food supply. In January 1999 USDA/APHIS published in the Federal Register a rule which authorized irradiation as a guarantee treatment for papayas for movement from Hawaii to the US mainland. This treatment was never used for a number of reasons. However, in December, 1993, the US Environmental Protection Agency (EPA) published its final rule to terminate production and consumption of methyl bromide, the only remaining broad spectrum fumigant for disinfesting agricultural commodities for pests of quarantine significance on imported and exported commodities. With increased global trade pressures and the possible loss of methyl bromide as a fumigant for regulatory pests treatment made it imperative that practical treatment options be explored including irradiation. In May 1996, USDA/APHIS published a Notice of Policy which sets forth a policy statement that share positions and policies of USDA concerning the use of irradiation as a phytosanitary treatment. Subsequently in July, 1997, USDA/APHIS amended its Hawaiian regulation by increasing the dose required for papayas intended for interstate movement and by allowing carambolas and litchis also to move interstate as well. Fruits from Hawaii to the US mainland are currently being irradiated and distributed in commerce throughout the US Irradiation treatments now afford movement of many exotic fruits to the US mainland that could not be done earlier due to the lack of available treatment methods. To help combat this potential public health problem, the US Food and Drug Administration (FDA) approved treating red meat products. This process has been favorably received by the US food industries and health organizations because it can control E. coli 0157:H7 and several other disease-causing microorganisms. However, irradiation will not be authorized until the USDA Food Safety and Inspection Service (FSIS), the US federal agency that regulates meat and poultry products, finalizes it regulations.

Peri-implant osseointegration after low-level laser therapy: micro-computed tomography and resonance frequency analysis in an animal model.

PubMed

Mayer, Luciano; Gomes, Fernando Vacilotto; de Oliveira, Marília Gerhardt; de Moraes, João Feliz Duarte; Carlsson, Lennart

2016-12-01

The purpose of the present study is to evaluate the effects of low-level laser therapy on the osseointegration process by comparing resonance frequency analysis measurements performed at implant placement and after 30 days and micro-computed tomography images in irradiated vs nonirradiated rabbits. Fourteen male New Zealand rabbits were randomly divided into two groups of seven animals each, one control group (nonirradiated animals) and one experimental group that received low-level laser therapy (Thera Lase®, aluminum-gallium-arsenide laser diode, 10 J per spot, two spots per session, seven sessions, 830 nm, 50 mW, CW, Ø 0.0028 cm 2 ). The mandibular left incisor was surgically extracted in all animals, and one osseointegrated implant was placed immediately afterward (3.25ø × 11.5 mm; NanoTite, BIOMET 3i). Resonance frequency analysis was performed with the Osstell® device at implant placement and at 30 days (immediately before euthanasia). Micro-computed tomography analyses were then conducted using a high-resolution scanner (SkyScan 1172 X-ray Micro-CT) to evaluate the amount of newly formed bone around the implants. Irradiated animals showed significantly higher implant stability quotients at 30 days (64.286 ± 1.596; 95 % confidence interval (CI) 60.808-67.764) than controls (56.357 ± 1.596; 95 %CI 52.879-59.835) (P = .000). The percentage of newly formed bone around the implants was also significantly higher in irradiated animals (75.523 ± 8.510; 95 %CI 61.893-89.155) than in controls (55.012 ± 19.840; 95 %CI 41.380-68.643) (P = .027). Laser therapy, based on the irradiation protocol used in this study, was able to provide greater implant stability and increase the volume of peri-implant newly formed bone, indicating that laser irradiation effected an improvement in the osseointegration process.

Nitrogen-atom endohedral fullerene synthesis with high efficiency by controlling plasma-ion irradiation energy and C{sub 60} internal energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, Soon Cheon; Kaneko, Toshiro, E-mail: kaneko@ecei.tohoku.ac.jp; Ishida, Hiroyasu

2015-03-28

The nitrogen-atom endohedral fullerene (N@C{sub 60}) has been synthesized by controlling the plasma ion irradiation energy (E{sub i}) and fullerene (C{sub 60}) behavior in the sublimation phase. We examined the relationship between the synthesis purity of N@C{sub 60} [molar concentration ratio of N@C{sub 60} to pristine fullerene (C{sub 60})] and E{sub i}, which was controlled by changing the substrate bias voltages (V{sub sub}) and gas pressure (P{sub N2}) during the plasma irradiation process. High-density nitrogen-molecular ions (N{sub 2}{sup +}) with a suitable E{sub i} near 80 eV are confirmed to be the optimum condition of the nitrogen plasma for themore » synthesis of high-purity N@C{sub 60}. In addition, high sublimation of C{sub 60} contributes to a higher yield due to the high internal energy of C{sub 60} and the related cage defects that are present under these conditions. As a result, a purity of 0.83% is realized for the first time, which is almost two orders of magnitude higher than that using other methods.« less

Application of gamma irradiation for aging control and improvement of shelf-life of kimchi, korean salted and fermented vegetables

NASA Astrophysics Data System (ADS)

Song, Hyun-Pa; Kim, Dong-Ho; Yook, Hong-Sun; Kim, Kyung-Soo; Kwon, Joong-Ho; Byun, Myung-Woo

2004-09-01

This study was carried out to evaluate the application of food irradiation as a method for extending shelf life of Kimchi. Gamma irradiation up to 10 kGy in the early stage of Kimchi fermentation had a dose-dependent effect on the inactivation of fermentative microbes, lowering the lactate dehydrogenase (LDH) activity and delaying acidification. Although gamma irradiation on the mid-fermentation stage of Kimchi inactivated the fermentative microbes effectively, LDH activity remained high and acidification continued. Kimchi irradiated at 10 kGy had lower scores in acceptability than those of control, 2.5 and 5 kGy irradiated. Therefore, gamma irradiation upto 5 kGy in the early fermentation stage is recommended for aging control and the improvement of shelf life of Kimchi.

Mortality, size of the gonads, and ultrastructure of primordial germ cell in chick embryos treated with gamma-irradiation or injected with donor cells.

PubMed

Maeda, T; Clark, M E; Etches, R J

1998-06-01

The effects of injection and/or gamma-irradiation prior to injection on mortality, size of the gonads, and ultrastructure of primordial germ cell (PGC) were examined after 5 d of incubation. The mortality of embryos injected with donor cells was significantly higher than that of control and irradiated embryos. All irradiated embryos were alive, although their development was delayed compared to those not exposed to irradiation. The size of the gonads of embryos injected with donor cells were similar to those of control embryos, however, the size of the gonads in irradiated embryos was significantly smaller than those of control embryos. The number of PGC in the gonads was significantly decreased by irradiation. There was no notable effect of irradiation or injection on the nuclei and cytoplasmic organelles in PGC.

Effect of low-level laser therapy on the post-surgical inflammatory process after third molar removal: study protocol for a double-blind randomized controlled trial.

PubMed

Oliveira Sierra, Simone; Melo Deana, Alessandro; Mesquita Ferrari, Raquel Agnelli; Maia Albarello, Priscilla; Bussadori, Sandra Kalil; Santos Fernandes, Kristianne Porta

2013-11-06

Low-level laser therapy (LLLT) has been shown to modulate the inflammatory process without adverse effects , by reducing pain and swelling and promoting the repair of damaged tissues. Because pain, swelling and muscle spasm are complications found in virtually all patients following oral surgery for the removal of impacted teeth, this model has been widely used to evaluate the effects of LLLT on the inflammatory process involving bone and, connective tissue and the muscles involved in mastication. After meeting the eligibility criteria, 60 patients treated at a Specialty Dental Center for the removal of impacted lower third molars will be randomly divided into five groups according to the type of laser therapy used at the end of surgery (intraoral irradiation with 660 nm laser; extraoral irradiation with 660 nm laser; intraoral irradiation with 808 nm laser; extraoral irradiation with 808 nm laser and no irradiation). To ensure that patients are blinded to the type of treatment they are receiving, the hand piece of the laser apparatus will be applied both intraorally and extraorally to all participants, but the device will be turned on only at the appropriate time, as determined by the randomization process. At 2 and 7 days after surgery, the patients will be evaluated by three blinded evaluators who will measure of swelling, mouth opening (muscle spasm evaluation) and pain (using two different pain scales). The 14-item Oral Health Impact Profile (OHIP-14) will be used to assess QOL. All data will be analyzed with respect to the normality of distribution using the Shapiro-Wilk test. Statistically significant differences between the experimental groups will be determined using analysis of variance, followed by a suitable post hoc test, when necessary. The significance level will be set at α = 0.05. The lack of standardization in studies with regard to the samples, methods and LLLT parameters complicates the determination of the actual effect of laser therapy on this model. The present study aims to provide a randomized, controlled, double-blind trial to compare four different LLLT parameters in relation to the outcomes of pain, swelling and muscle spasm following surgery for the extraction of impacted third molars and evaluate the effects os surgery on patients' quality os life (QOL). Brazilian Registry of Clinical Trials - Rebec (RBR-6XSB5H).

Effects of fibers and fabrication processes on mechanical properties of neutron irradiated SiC/SiC composites

NASA Astrophysics Data System (ADS)

Nozawa, T.; Hinoki, T.; Katoh, Y.; Kohyama, A.

2002-12-01

Radiation effects on flexural properties of SiC/SiC composites fabricated by forced thermal gradient chemical vapor infiltration (F-CVI) process, reaction sintered (RS) process and polymer impregnation and pyrolysis (PIP) process were investigated. In this study, neutron irradiation at 1073 K up to 0.4×10 25 n/m 2 ( E>0.1 MeV) was performed. For F-CVI and RS SiC/SiC, due to the irradiation damage of interphase like pyrolytic carbon and boron nitride, which were sensitive to neutron irradiation, composite stiffness was slightly decreased. On the contrary, for PIP SiC/SiC, there was no significant change in stiffness before and after irradiation. Composite strength, however, was nearly stable against high-temperature irradiation with such a low fluence, except for RS SiC/SiC, since mechanical characteristics of fiber and matrix themselves were still stable to neutron irradiation. However RS SiC/SiC had a slight reduction of flexural strength due to the severe degradation of the interface by neutron irradiation.

Coherent control of alkali cluster fragmentation dynamics

NASA Astrophysics Data System (ADS)

Lindinger, Albrecht; Lupulescu, Cosmin; Bartelt, Andreas; Vajda, Štefan; Wöste, Ludger

2003-06-01

Metal clusters exhibit extraordinary chemical and catalytic properties, which sensitively depend upon their size. This behavior makes them interesting candidates for the real-time analysis of ultrafast photo-induced processes—ultimately leading to coherent control scenarii. We have performed transient multi-photon ionization experiments on small alkali clusters of different size in order to probe their wave packet dynamics, structural reorientations, charge transfers and dissociative events in different vibrationally excited electronic states including their ground state. The observed processes were highly dependent on the irradiated pulse parameters, like its phase, amplitude and duration; an emphasis to employ a feedback control system for generating the optimum pulse shapes. Their spectral and temporal behavior reflects interesting properties about the investigated system and the irradiated photochemical process. We present first the vibrational dynamics of bound, dissociated, and pre-dissociated electronically excited states of alkali dimers and trimers. The scheme for observing the wave packet dynamics in the electronic ground state using stimulated Raman-pumping is shown. Since the employed pulse parameters significantly influence the efficiency of the irradiated dynamic pathways photo-induced fragmentation experiments on bifurcating reaction channels were carried out. In these experiments different branching ionization and fragmentation pathways of electronically excited Na 2K were investigated. By employing an evolutionary algorithm for optimizing the phase and amplitude of the applied laser field, the yield of the resulting parent or fragment ions could significantly be influenced and interesting features could be concluded from the obtained optimum pulse shapes revealing the characteristic molecular oscillation period. Moreover, the influence on the optimal pulse shape due to fragmentation from larger clusters into NaK is obtained. The substructure of the optimal pulse shape thereby offers new insight into the fragmentation channel during the control process. Characteristic motions of the involved wave packets are proposed, in order to explain the optimized dynamic dissociation pathways.

Investigation of the effect of power ultrasound on the nucleation of water during freezing of agar gel samples in tubing vials.

PubMed

Kiani, Hossein; Sun, Da-Wen; Delgado, Adriana; Zhang, Zhihang

2012-05-01

Nucleation, as an important stage of freezing process, can be induced by the irradiation of power ultrasound. In this study, the effect of irradiation temperature (-2 °C, -3 °C, -4 °C and -5 °C), irradiation duration (0s, 1s, 3s, 5s, 10s or 15s) and ultrasound intensity (0.07 W cm(-2), 0.14 W cm(-2), 0.25 W cm(-2), 0.35 W cm(-2) and 0.42 W cm(-2)) on the dynamic nucleation of ice in agar gel samples was studied. The samples were frozen in an ethylene glycol-water mixture (-20 °C) in an ultrasonic bath system after putting them into tubing vials. Results indicated that ultrasound irradiation is able to initiate nucleation at different supercooled temperatures (from -5 °C to -2 °C) in agar gel if optimum intensity and duration of ultrasound were chosen. Evaluation of the effect of 0.25 W cm(-2) ultrasound intensity and different durations of ultrasound application on agar gels showed that 1s was not long enough to induce nucleation, 3s induced the nucleation repeatedly but longer irradiation durations resulted in the generation of heat and therefore nucleation was postponed. Investigation of the effect of ultrasound intensity revealed that higher intensities of ultrasound were effective when a shorter period of irradiation was used, while lower intensities only resulted in nucleation when a longer irradiation time was applied. In addition to this, higher intensities were not effective at longer irradiation times due to the heat generated in the samples by the heating effect of ultrasound. In conclusion, the use of ultrasound as a means to control the crystallization process offers promising application in freezing of solid foods, however, optimum conditions should be selected. Copyright © 2011 Elsevier B.V. All rights reserved.

[Image-guided radiotherapy and partial delegation to radiotherapy technicians: Clermont-Ferrand experience].

PubMed

Loos, G; Moreau, J; Miroir, J; Benhaïm, C; Biau, J; Caillé, C; Bellière, A; Lapeyre, M

2013-10-01

The various image-guided radiotherapy techniques raise the question of how to achieve the control of patient positioning before irradiation session and sharing of tasks between radiation oncologists and radiotherapy technicians. We have put in place procedures and operating methods to make a partial delegation of tasks to radiotherapy technicians and secure the process in three situations: control by orthogonal kV imaging (kV-kV) of bony landmarks, control by kV-kV imaging of intraprostatic fiducial goldmarkers and control by cone beam CT (CBCT) imaging for prostate cancer. Significant medical overtime is required to control these three IGRT techniques. Because of their competence in imaging, these daily controls can be delegated to radiotherapy technicians. However, to secure the process, initial training and regular evaluation are essential. The analysis of the comparison of the use of kV/kV on bone structures allowed us to achieve a partial delegation of control to radiotherapy technicians. Controlling the positioning of the prostate through the use and automatic registration of fiducial goldmarkers allows better tracking of the prostate and can be easily delegated to radiotherapy technicians. The analysis of the use of daily cone beam CT for patients treated with intensity modulated irradiation is underway, and a comparison of practices between radiotherapy technicians and radiation oncologists is ongoing to know if a partial delegation of this control is possible. Copyright © 2013. Published by Elsevier SAS.

Physicochemical fabrication of antibacterial calcium phosphate submicrospheres with dispersed silver nanoparticles via coprecipitation and photoreduction under laser irradiation.

PubMed

Nakamura, Maki; Oyane, Ayako; Shimizu, Yoshiki; Miyata, Saori; Saeki, Ayumi; Miyaji, Hirofumi

2016-12-01

We achieved rapid, surfactant-free, and one-pot fabrication of antibacterial calcium phosphate (CaP) submicrospheres containing silver nanoparticles by combining physical laser and chemical coprecipitation processes. In this physicochemical process, weak pulsed laser irradiation (20min) was performed on a labile CaP reaction mixture supplemented with silver ions as a light-absorbing agent. The silver content in the submicrospheres was controlled for a wide range (Ag/P elemental ratio varied from 0.60 to 62.0) by tuning the initial concentration of silver ions (from 5 to 20mM) in the CaP reaction mixture. At the silver concentration of 5mM, we obtained unique nanocomposite particles: CaP submicrospheres (average diameter of approximately 500nm) containing metallic silver nanoparticles dispersed throughout, as a result of CaP and silver coprecipitation with simultaneous photoreduction of silver ions and spheroidization of the coprecipitates. These CaP submicrospheres containing silver nanoparticles (ca. 0.3mg silver per 1mg submicrospheres) exhibited antibacterial activity against major pathogenic oral bacteria, i.e., Streptococcus mutans, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis. Moreover, the CaP submicrospheres dissolved and neutralized the acidic environment generated by Streptococcus mutans, demonstrating their potential as acid-neutralizing and remineralizing agents. The present process and resulting antibacterial CaP-based submicrospheres are expected to be useful in dental healthcare and infection control. Nano- and microsized spheres of calcium phosphate (CaP) containing silver nanoparticles have great potential in dental applications. Conventional fabrication processes were time-consuming or weak regarding the size/shape control of the spheres. In this study, we achieved a simple (one-pot), rapid (20-min irradiation), and surfactant-free fabrication of CaP submicrospheres containing silver nanoparticles by pulsed laser irradiation to a mixture of calcium, phosphate, and silver ion solutions. The resulting CaP submicrospheres contained metallic silver nanoparticles dispersed throughout in a sequence of reactions: CaP and silver coprecipitation, laser-induced melting and spheroidization of the coprecipitates, and photoreduction of silver ions. These submicrospheres showed antibacterial activity against oral bacteria and acid-neutralizing property in the bacterial suspension, and hence are worth considering for dental applications. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Fractal model of polarization switching kinetics in ferroelectrics under nonequilibrium conditions of electron irradiation

NASA Astrophysics Data System (ADS)

Maslovskaya, A. G.; Barabash, T. K.

2018-03-01

The paper presents the results of the fractal and multifractal analysis of polarization switching current in ferroelectrics under electron irradiation, which allows statistical memory effects to be estimated at dynamics of domain structure. The mathematical model of formation of electron beam-induced polarization current in ferroelectrics was suggested taking into account the fractal nature of domain structure dynamics. In order to realize the model the computational scheme was constructed using the numerical solution approximation of fractional differential equation. Evidences of electron beam-induced polarization switching process in ferroelectrics were specified at a variation of control model parameters.

Protection against free radicals (UVB irradiation) of a water-soluble enzymatic extract from rice bran. Study using human keratinocyte monolayer and reconstructed human epidermis.

PubMed

Santa-María, C; Revilla, E; Miramontes, E; Bautista, J; García-Martínez, A; Romero, E; Carballo, M; Parrado, J

2010-01-01

The antioxidant capacity of a water-soluble enzymatic extract from rice bran (EERB) has been tested in two cell models: keratinocyte monolayers and human reconstructed epidermis. Cells were incubated in culture medium in presence of different amounts of EERB and were UVB irradiated. Cell population assessment (MTT assay) and MDA (malonaldehyde) production were evaluated. The EERB did not induce cytotoxic effect for concentrations inferior or equal to 100 microg/mL. Human keratinocyte monolayers were protected of irradiation preventing 33% the lipid peroxidation process at concentration of 10 microg/ml of EEBR. In reconstructed human epidermis, 100 microg/mL decreased lipid peroxidation process by 44% (p<0.01) with regards to irradiated negative control. This effect was comparable to that of vitamin E at 600 microg/mL. Our data indicate that EERB is potentially able to efficiently counteract UVB-induced response. The EERB, diluted at 10% with water has very good skin compatibility. This product showed a sun protection factor of 4.8+/-0.3. Thus we can propose EERB as a useful natural standardized extract in skin photoprotection with promising applications in the field of dermatology. Copyright 2009 Elsevier Ltd. All rights reserved.

General lighting requirements for photosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geiger, D.R.

1994-12-31

A review of the general lighting requirements for photosynthesis reveals that four aspects of light are important: irradiance, quality, timing and duration. These properties of light affect photosynthesis by providing the energy that drives carbon assimilation as well as by exerting control over physiology, structure and morphology of plants. Irradiance, expressed as energy flux, W m{sup -2}, or photon irradiance, {mu}mol m{sup -2} s{sup -1}, determines the rate at which energy is being delivered to the photosynthetic reaction centers. Spectral quality, the wavelength composition of light, is important because photons differ in their probability of being absorbed by the lightmore » harvesting complex and hence their ability to drive carbon assimilation. Also the various light receptors for light-mediated regulation of plant form and physiology have characteristic absorption spectra and hence photons differ in their effectiveness for eliciting responses. Duration is important because both carbon assimilation and regulation are affected by the total energy or integrated irradiance delivered during a given period. Many processes associated with photosynthesis are time-dependent, increasing or decreasing with duration. Timing is important because the effectiveness of light in the regulation of plant processes varies with the phase of the diumal cycle as determined by the plant`s time-measuring mechanisms.« less

Effect of freezing, irradiation, and frozen storage on survival of Salmonella in concentrated orange juice.

PubMed

Niemira, Brendan A; Sommers, Christopher H; Boyd, Glenn

2003-10-01

Six strains of Salmonella (Anatum F4317, Dublin 15480, Enteritidis 13076, Enteritidis WY15159, Stanley H0588, and Typhimurium 14028) were individually inoculated into orange juice concentrate (OJC) and frozen to -20 degrees C. The frozen samples were treated with 0 (nonirradiated), 0.5, 1.0, or 2.0 kGy of gamma radiation and held frozen for 1 h, and the surviving bacterial population was assessed. The strains showed significant variability in their response to freezing and to freezing in combination with irradiation. The response was dose dependent. Relative to the nonfrozen, nonirradiated control, the reduction following the highest dose (2.0 kGy) ranged from 1.29 log CFU/ml (Salmonella Typhimurium) to 2.17 log CFU/ml (Salmonella Stanley). Samples of OJC inoculated with Salmonella Enteritidis WY15159 and irradiated were stored at -20 degrees C for 1, 2, 7, or 14 days, and the surviving population was determined. Relative to the nonfrozen, nonirradiated control, after 14 days, the population was reduced by 1.2 log CFU/ml in the nonirradiated samples and by 3.3 log CFU/ml following treatment with 2.0 kGy. The combination of frozen storage plus irradiation resulted in greater overall reductions than either process alone.

Verification of a new biocompatible single-use film formulation with optimized additive content for multiple bioprocess applications.

PubMed

Jurkiewicz, Elke; Husemann, Ute; Greller, Gerhard; Barbaroux, Magali; Fenge, Christel

2014-01-01

Single-use bioprocessing bags and bioreactors gained significant importance in the industry as they offer a number of advantages over traditional stainless steel solutions. However, there is continued concern that the plastic materials might release potentially toxic substances negatively impacting cell growth and product titers, or even compromise drug safety when using single-use bags for intermediate or drug substance storage. In this study, we have focused on the in vitro detection of potentially cytotoxic leachables originating from the recently developed new polyethylene (PE) multilayer film called S80. This new film was developed to guarantee biocompatibility for multiple bioprocess applications, for example, storage of process fluids, mixing, and cell culture bioreactors. For this purpose, we examined a protein-free cell culture medium that had been used to extract leachables from freshly gamma-irradiated sample bags in a standardized cell culture assay. We investigated sample bags from films generated to establish the operating ranges of the film extrusion process. Further, we studied sample bags of different age after gamma-irradiation and finally, we performed extended media extraction trials at cold room conditions using sample bags. In contrast to a nonoptimized film formulation, our data demonstrate no cytotoxic effect of the S80 polymer film formulation under any of the investigated conditions. The S80 film formulation is based on an optimized PE polymer composition and additive package. Full traceability alongside specifications and controls of all critical raw materials, and process controls of the manufacturing process, that is, film extrusion and gamma-irradiation, have been established to ensure lot-to-lot consistency. © 2014 American Institute of Chemical Engineers.

Experimental analysis and modeling of ultrasound assisted freezing of potato spheres.

PubMed

Kiani, Hossein; Zhang, Zhihang; Sun, Da-Wen

2015-09-01

In recent years, innovative methods such as ultrasound assisted freezing have been developed in order to improve the freezing process. During freezing of foods, accurate prediction of the temperature distribution, phase ratios, and process time is very important. In the present study, ultrasound assisted immersion freezing process (in 1:1 ethylene glycol-water solution at 253.15K) of potato spheres (0.02 m diameter) was evaluated using experimental, numerical and analytical approaches. Ultrasound (25 kHz, 890 W m(-2)) was irradiated for different duty cycles (DCs=0-100%). A finite volume based enthalpy method was used in the numerical model, based on which temperature and liquid fraction profiles were simulated by a program developed using OpenFOAM® CFD software. An analytical technique was also employed to calculate freezing times. The results showed that ultrasound irradiation could decrease the characteristic freezing time of potatoes. Since ultrasound irradiation increased the heat transfer coefficient but simultaneously generated heat at the surface of the samples, an optimum DC was needed for the shortest freezing time which occurred in the range of 30-70% DC. DCs higher than 70% increased the freezing time. DCs lower than 30% did not provide significant effects on the freezing time compared to the control sample. The numerical model predicted the characteristic freezing time in accordance with the experimental results. In addition, analytical calculation of characteristic freezing time exhibited qualitative agreement with the experimental results. As the numerical simulations provided profiles of temperature and water fraction within potatoes frozen with or without ultrasound, the models can be used to study and control different operation situations, and to improve the understanding of the freezing process. Copyright © 2015 Elsevier B.V. All rights reserved.

PHOTONICS AND NANOTECHNOLOGY Laser-induced modification of transparent crystals and glasses

NASA Astrophysics Data System (ADS)

Bulgakova, N. M.; Stoian, Razvan; Rosenfeld, A.

2010-12-01

We analyse the processes taking place in transparent crystals and glasses irradiated by ultrashort laser pulses in the regimes typical of various applications in optoelectronics and photonics. We consider some phenomena, which have been previously described by the authors within the different model representations: charging of the dielectric surface due to electron photoemission resulting in a Coulomb explosion; crater shaping by using an adaptive control of the laser pulse shape; optimisation of the waveguide writing in materials strongly resistant to laser-induced compaction under ordinary irradiation conditions. The developed models and analysis of the processes relying on these models include the elements of the solid-state physics, plasma physics, thermodynamics, theory of elasticity and plasticity. Some important experimental observations which require explanations and adequate description are summarised.

Optical cell separation from three-dimensional environment in photodegradable hydrogels for pure culture techniques.

PubMed

Tamura, Masato; Yanagawa, Fumiki; Sugiura, Shinji; Takagi, Toshiyuki; Sumaru, Kimio; Matsui, Hirofumi; Kanamori, Toshiyuki

2014-05-07

Cell sorting is an essential and efficient experimental tool for the isolation and characterization of target cells. A three-dimensional environment is crucial in determining cell behavior and cell fate in biological analysis. Herein, we have applied photodegradable hydrogels to optical cell separation from a 3D environment using a computer-controlled light irradiation system. The hydrogel is composed of photocleavable tetra-arm polyethylene glycol and gelatin, which optimized cytocompatibility to adjust a composition of crosslinker and gelatin. Local light irradiation could degrade the hydrogel corresponding to the micropattern image designed on a laptop; minimum resolution of photodegradation was estimated at 20 µm. Light irradiation separated an encapsulated fluorescent microbead without any contamination of neighbor beads, even at multiple targets. Upon selective separation of target cells in the hydrogels, the separated cells have grown on another dish, resulting in pure culture. Cell encapsulation, light irradiation and degradation products exhibited negligible cytotoxicity in overall process.

Study on optimizing ultrasonic irradiation period for thick polycrystalline PZT film by hydrothermal method.

PubMed

Ohta, Kanako; Isobe, Gaku; Bornmann, Peter; Hemsel, Tobias; Morita, Takeshi

2013-04-01

The hydrothermal method utilizes a solution-based chemical reaction to synthesize piezoelectric thin films and powders. This method has a number of advantages, such as low-temperature synthesis, and high purity and high quality of the product. In order to promote hydrothermal reactions, we developed an ultrasonic assisted hydrothermal method and confirmed that it produces dense and thick lead-zirconate-titanate (PZT) films. In the hydrothermal method, a crystal growth process follows the nucleation process. In this study, we verified that ultrasonic irradiation is effective for the nucleation process, and there is an optimum irradiation period to obtain thicker PZT films. With this optimization, a 9.2-μm-thick PZT polycrystalline film was obtained in a single deposition process. For this film, ultrasonic irradiation was carried out from the beginning of the reaction for 18 h, followed by a 6 h deposition without ultrasonic irradiation. These results indicate that the ultrasonic irradiation mainly promotes the nucleation process. Copyright © 2012 Elsevier B.V. All rights reserved.

78 FR 34565 - Irradiation in the Production, Processing, and Handling of Animal Feed and Pet Food; Electron...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-10

.... FDA-2012-F-0178] Irradiation in the Production, Processing, and Handling of Animal Feed and Pet Food; Electron Beam and X-Ray Sources for Irradiation of Poultry Feed and Poultry Feed Ingredients; Correction... Administration (FDA) is correcting a document amending the regulations for irradiation of animal feed and pet...

78 FR 27303 - Irradiation in the Production, Processing, and Handling of Animal Feed and Pet Food; Electron...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-10

...-0178] Irradiation in the Production, Processing, and Handling of Animal Feed and Pet Food; Electron Beam and X-Ray Sources for Irradiation of Poultry Feed and Poultry Feed Ingredients AGENCY: Food and... amending the regulations for irradiation of animal feed and pet food to provide for the safe use of...

In situ growth of copper nanocrystals from carbonaceous microspheres with electrochemical glucose sensing properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Xiaoliang; Yan, Zhengguang, E-mail: yanzg2004@gmail.com; Han, Xiaodong, E-mail: xdhan@bjut.edu.cn

2014-02-01

Graphical abstract: In situ growth of copper nanoparticles from hydrothermal copper-containing carbonaceous microspheres was induced by annealing or electron beam irradiation. Obtained micro-nano carbon/copper composite microspheres show electrochemical glucose sensing properties. - Highlights: • We synthesized carbonaceous microspheres containing non-nanoparicle copper species through a hydrothermal route. • By annealing or electron beam irradiation, copper nanoparticles would form from the carbonaceous microspheres in situ. • By controlling the annealing temperature, particle size of copper could be controlled in the range of 50–500 nm. • The annealed carbon/copper hierarchical composite microspheres were used to fabricate an electrochemical glucose sensor. - Abstract: Inmore » situ growth of copper nanocrystals from carbon/copper microspheres was observed in a well-controlled annealing or an electron beam irradiation process. Carbonaceous microspheres containing copper species with a smooth appearance were yielded by a hydrothermal synthesis using copper nitrate and ascorbic acid as reactants. When annealing the carbonaceous microspheres under inert atmosphere, copper nanoparticles were formed on carbon microspheres and the copper particle sizes can be increased to a range of 50–500 nm by altering the heating temperature. Similarly, in situ formation of copper nanocrystals from these carbonaceous microspheres was observed on the hydrothermal product carbonaceous microspheres with electron beam irradiation in a vacuum transmission electron microscopy chamber. The carbon/copper composite microspheres obtained through annealing were used to modify a glassy carbon electrode and tested as an electrochemical glucose sensor.« less

Effects of processing and dopant on radiation damage removal in silicon solar cells

NASA Technical Reports Server (NTRS)

Weinberg, I.; Brandhorst, H. W., Jr.; Swartz, C. K.; Mehta, S.

1982-01-01

Gallium and boron doped silicon solar cells, processed by ion-implantation followed by either laser or furnace anneal were irradiated by 1 MeV electrons and their post-irradiation recovery by thermal annealing determined. During the post-irradiation anneal, gallium-doped cells prepared by both processes recovered more rapidly and exhibited none of the severe reverse annealing observed for similarly processed 2 ohm-cm boron doped cells. Ion-implanted furnace annealed 0.1 ohm-cm boron doped cells exhibited the lowest post-irradiation annealing temperatures (200 C) after irradiation to 5 x 10 to the 13th e(-)/sq cm. The drastically lowered recovery temperature is attributed to the reduced oxygen and carbon content of the 0.1 ohm-cm cells. Analysis based on defect properties and annealing kinetics indicates that further reduction in annealing temperature should be attainable with further reduction in the silicon's carbon and/or divacancy content after irradiation.

Titanium nitride formation by a dual-stage femtosecond laser process

NASA Astrophysics Data System (ADS)

Hammouti, S.; Holybee, B.; Zhu, W.; Allain, J. P.; Jurczyk, B.; Ruzic, D. N.

2018-06-01

Formation of TiN by femtosecond laser processing in controlled gas atmosphere is reported. A dual-stage process was designed and aimed to first remove and restructure the native oxide layer of titanium surface through laser irradiation under an argon-controlled atmosphere, and then to maximize titanium nitride formation through an irradiation under a nitrogen reactive environment. An extensive XPS study was performed to identify and quantify laser-induced titanium surface chemistry modifications after a single-stage laser process (Ar and N2 individually), and a dual-stage laser process. The importance of each step that composes the dual-stage laser process was demonstrated and leads to the dual-stage laser process for the formation of TiO, Ti2O3 and TiN. In this study, the largest nitride formation occurs for the dual stage process with laser conditions at 4 W/1.3 J cm-2 under argon and 5 W/1.6 J cm-2 under nitrogen, yielding a total TiN composition of 8.9%. Characterization of both single-stage and dual-stage laser process-induced surface morphologies has been performed as well, leading to the observation of a wide range of hierarchical surface structures such as high-frequency ripples, grooves, protuberances and pillow-like patterns. Finally, water wettability was assessed by means of contact angle measurements on untreated titanium surface, and titanium surfaces resulting from either single-stage laser process or dual-stage laser process. Dual-stage laser process allows a transition of titanium surface, from phobic (93°) to philic (35°), making accessible both hydrophilic and chemically functionalized hierarchical surfaces.

Roll-to-roll-compatible, flexible, transparent electrodes based on self-nanoembedded Cu nanowires using intense pulsed light irradiation

NASA Astrophysics Data System (ADS)

Zhong, Zhaoyang; Woo, Kyoohee; Kim, Inhyuk; Hwang, Hyewon; Kwon, Sin; Choi, Young-Man; Lee, Youngu; Lee, Taik-Min; Kim, Kwangyoung; Moon, Jooho

2016-04-01

Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced oxidation stability. Moreover, Cu NW FTCEs with high uniformities are successfully fabricated on a large area (150 mm × 200 mm) via successive IPL irradiation that is synchronized with the motion of the sample stage. This study demonstrates the possibility of roll-to-roll-based, large-scale production of low-cost, high-performance Cu NW-based FTCEs.Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced oxidation stability. Moreover, Cu NW FTCEs with high uniformities are successfully fabricated on a large area (150 mm × 200 mm) via successive IPL irradiation that is synchronized with the motion of the sample stage. This study demonstrates the possibility of roll-to-roll-based, large-scale production of low-cost, high-performance Cu NW-based FTCEs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00444j

Controlled gas-liquid interfacial plasmas for synthesis of nano-bio-carbon conjugate materials

NASA Astrophysics Data System (ADS)

Kaneko, Toshiro; Hatakeyama, Rikizo

2018-01-01

Plasmas generated in contact with a liquid have been recognized to be a novel reactive field in nano-bio-carbon conjugate creation because several new chemical reactions have been yielded at the gas-liquid interface, which were induced by the physical dynamics of non-equilibrium plasmas. One is the ion irradiation to a liquid, which caused the spatially selective dissociation of the liquid and the generation of additive reducing and oxidizing agents, resulting in the spatially controlled synthesis of nanostructures. The other is the electron irradiation to a liquid, which directly enhanced the reduction action at the plasma-liquid interface, resulting in temporally controlled nanomaterial synthesis. Using this novel reaction field, gold nanoparticles with controlled interparticle distance were synthesized using carbon nanotubes as a template. Furthermore, nanoparticle-biomolecule conjugates and nanocarbon-biomolecule conjugates were successfully synthesized by an aqueous-solution contact plasma and an electrolyte plasma, respectively, which were rapid and low-damage processes suitable for nano-bio-carbon conjugate materials.

Dental resin curing blue light induces vasoconstriction through release of hydrogen peroxide.

PubMed

Oktay, Elif Aybala; Tort, Huseyin; Yıldız, Oguzhan; Ulusoy, Kemal Gokhan; Topcu, Fulya Toksoy; Ozer, Cigdem

2018-05-26

Dental resin curing blue light (BL) is frequently used during treatments in dental clinics. However, little is known about the influence of BL irradiation on pulpal blood vessels. The aim of the present study was to investigate the mechanism of effect of BL irradiation on vascular tone. Rat aorta (RA) rings were irradiated with a BL source in organ baths, and the responses were recorded isometrically. Effect of BL irradiation on phenylephrine (PE) -precontraction and acetylcholine (ACh) -induced relaxation after PE -precontraction were obtained and compared in BL -irradiated and control RA rings. Effect of 20 min preincubation with catalase (enzyme that breaks down hydrogene peroxide, 1200 u/ml) on PE -precontraced and BL-irradiated rings was also evaluated. Total oxidative stress (TOS) and total antioxidant capacity (TAC) in BL-irradiated and control RA preparations were measured with special assay kits and spectrophotometry. BL slightly decreased ACh -induced endothelium -dependent relaxations in PE (1 μM) -precontracted RA rings (n = 6, p > 0.05 vs. control). BL induced marked contraction 23.88 + 3.10% of PE (maximum contraction) in isolated RA ring segments precontracted with PE (p < 0.05 vs. control). The contractile effect of BL was inhibited by 1200 u/ml catalase (n = 6, p < 0.05 vs. control). BL irradiation increased the level of TOS in RA rings (n = 6, p < 0.05 vs. control). TAC levels were similar in BL-irradiated and control preparations. These results suggest that BL induces contraction in RA, and the mechanism of this effect may to be through release of hydrogen peroxide. Copyright © 2018 Elsevier B.V. All rights reserved.

3D Printing Optical Engine for Controlling Material Microstructure

NASA Astrophysics Data System (ADS)

Huang, Wei-Chin; Chang, Kuang-Po; Wu, Ping-Han; Wu, Chih-Hsien; Lin, Ching-Chih; Chuang, Chuan-Sheng; Lin, De-Yau; Liu, Sung-Ho; Horng, Ji-Bin; Tsau, Fang-Hei

Controlling the cooling rate of alloy during melting and resolidification is the most commonly used method for varying the material microstructure and consequently the resuling property. However, the cooling rate of a selective laser melting (SLM) production is restricted by a preset optimal parameter of a good dense product. The head room for locally manipulating material property in a process is marginal. In this study, we invent an Optical Engine for locally controlling material microstructure in a SLM process. It develops an invovative method to control and adjust thermal history of the solidification process to gain desired material microstucture and consequently drastically improving the quality. Process parameters selected locally for specific materials requirement according to designed characteristics by using thermal dynamic principles of solidification process. It utilize a technique of complex laser beam shape of adaptive irradiation profile to permit local control of material characteristics as desired. This technology could be useful for industrial application of medical implant, aerospace and automobile industries.

Microstructured polymer films by X-ray lithographic exposure and grafting

NASA Astrophysics Data System (ADS)

Gürsel, Selmiye A.; Padeste, Celestino; Solak, Harun H.; Scherer, Günther G.

2005-07-01

Recently we reported on a new technique to generate micro- and nanostructured polymer materials by the combination of selective irradiation of polymer substrates with X-rays and subsequent grafting of a second polymer. Here we focus on the spatially defined grafting throughout the thickness of poly(ethylene-alt-tetrafluoroethylene) (ETFE) and poly (tetrafluoroethylene-co-hexafluoropropylene) (FEP) films using X-ray irradiation through a metal mask, followed by grafting with styrene. Calculations of the transmission of X-rays through the polymer as a function of the wavelength have revealed that energy deposition within the substrate material, which should control the density of created radicals, can be selected in a wide range. Depending on the used wavelength the radicals are created either near the surface or in the bulk of the sample. First experiments demonstrated spatially defined grafting through a 100 μm thick ETFE film and 25 μm thick FEP film. The achieved graft level depends on the irradiation dose as well as on the grafting parameters such as concentration, temperature and time. The precision of structure definition within the film depends on the properties of the X-ray source, the metal mask and the grafting process. The presented process allows controlled grafting through fluoropolymer films with micrometer resolution and local modification of the properties of the films, such as ion conductivity, diffusion of specific molecules or optical properties.

Near infrared light-mediated photoactivation of cytotoxic Re(i) complexes by using lanthanide-doped upconversion nanoparticles.

PubMed

Hu, Ming; Zhao, Jixian; Ai, Xiangzhao; Budanovic, Maja; Mu, Jing; Webster, Richard D; Cao, Qian; Mao, Zongwan; Xing, Bengang

2016-09-13

Platinum-based chemotherapy, although it has been well proven to be effective in the battle against cancer, suffers from limited specificity, severe side effects and drug resistance. The development of new alternatives with potent anticancer effects and improved specificity is therefore urgently needed. Recently, there are some new chemotherapy reagents based on photoactive Re(i) complexes which have been reported as promising alternatives to improve specificity mainly attributed to the spatial and temporal activation process by light irradiation. However, most of them respond to short-wavelength light (e.g. UV, blue or green light), which may cause unwanted photo damage to cells. Herein, we demonstrate a system for near-infrared (NIR) light controlled activation of Re(i) complex cytotoxicity by integration of photoactivatable Re(i) complexes and lanthanide-doped upconversion nanoparticles (UCNPs). Upon NIR irradiation at 980 nm, the Re(i) complex can be locally activated by upconverted UV light emitted from UCNPs and subsequently leads to enhanced cell lethality. Cytotoxicity studies showed effective inactivation of both drug susceptible human ovarian carcinoma A2780 cells and cisplatin resistant subline A2780cis cells by our UCNP based system with NIR irradiation, and there was minimum light toxicity observed in the whole process, suggesting that such a system could provide a promising strategy to control localized activation of Re(i) complexes and therefore minimize potential side effects.

The sterile insect technique for the management of the spotted wing drosophila, Drosophila suzukii: Establishing the optimum irradiation dose

PubMed Central

Brodeur, Jacques; Fournier, François; Martel, Véronique; Vreysen, Marc; Cáceres, Carlos; Firlej, Annabelle

2017-01-01

The spotted wing drosophila Drosophila suzukii Matsumura (Diptera: Drosophilidae), a pest of berries stone fruits, invaded North America and Europe in 2008. Current control methods rely mainly on insecticides. The sterile insect technique (SIT) has potential as an additional control tactic for the integrated management of D. suzukii. As a step towards the development of the SIT, this study aimed at finding the optimum irradiation dose to sterilize D. suzukii under controlled laboratory conditions. Four-day-old D. suzukii pupae were irradiated 12 to 24 hours prior to adult emergence in a 60Co Gamma Cell 220 and in a 137Cs Gamma Cell 3000 with doses of 30, 50, 70, 80, 90, 100 or 120 Gy. Emergence rate (88.1%), percent of deformed flies (4.0%) and survival curves were not affected by the tested irradiation doses. However, some reproductive parameters of the flies were affected by irradiation. Females irradiated with a dose of 50 Gy or more had almost no fecundity. When non-irradiated females were mated with irradiated males, egg hatch decreased exponentially with irradiation dose from 82.6% for the untreated control males to 4.0% for males irradiated with 120 Gy. Mortality of F1 individuals from the irradiated treatment also occurred during larval and pupal stages, with an egg to adult survival of 0.2%. However, descendants produced by the irradiated generation were fertile. These results are an encouraging first experimental step towards the development of the SIT for the management of D. suzukii populations. PMID:28957331

THE COURSE OF A SMALLPOX VACCINAL PROCESS AND THE FORMATION OF ANTISMALLPOX IMMUNITY IN RABBITS DUE TO THE EFFECT OF X IRRADIATION (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamalyan, L.A.

1961-01-01

A study of vaccination process peculiarities in rabbits, previously irradiated with an x-ray dose of 700 r, shows that the course of the process grows worse, the duration of the locai reaction becomes longer, the disease spreads and some of the animals die. A repeated infection of the rabbits (cutaneous and cerebral) shows that the intensity of antismallpox immunity is lower in irradiated animals than in nonirradiated ones in the case of primary and secondary immurization. A total irradiation suppresses the process of hemagglutination. (auth)

Stochastic Short-term High-resolution Prediction of Solar Irradiance and Photovoltaic Power Output

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melin, Alexander M.; Olama, Mohammed M.; Dong, Jin

The increased penetration of solar photovoltaic (PV) energy sources into electric grids has increased the need for accurate modeling and prediction of solar irradiance and power production. Existing modeling and prediction techniques focus on long-term low-resolution prediction over minutes to years. This paper examines the stochastic modeling and short-term high-resolution prediction of solar irradiance and PV power output. We propose a stochastic state-space model to characterize the behaviors of solar irradiance and PV power output. This prediction model is suitable for the development of optimal power controllers for PV sources. A filter-based expectation-maximization and Kalman filtering mechanism is employed tomore » estimate the parameters and states in the state-space model. The mechanism results in a finite dimensional filter which only uses the first and second order statistics. The structure of the scheme contributes to a direct prediction of the solar irradiance and PV power output without any linearization process or simplifying assumptions of the signal’s model. This enables the system to accurately predict small as well as large fluctuations of the solar signals. The mechanism is recursive allowing the solar irradiance and PV power to be predicted online from measurements. The mechanism is tested using solar irradiance and PV power measurement data collected locally in our lab.« less

Comparative immunohistologic studies in an adoptive transfer model of acute rat cardiac allograft rejection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forbes, R.D.; Lowry, R.P.; Gomersall, M.

1985-07-01

It has been shown that fulminant acute rejection of rat cardiac allografts across a full haplotype disparity may occur as a direct result of adoptive transfer of sensitized W3/25+ MRC OX8- SIg- T helper/DTH syngeneic spleen cells to sublethally irradiated recipients. In order to establish the immunohistologic parameters of this form of rejection, allografts and recipient lymphoid tissue were analyzed using a panel of monoclonal antibodies of known cellular distribution. These data were compared with those obtained following reconstitution of irradiated allograft recipients with unseparated sensitized spleen cells, with unreconstituted irradiated donor recipient pairs, with unmodified first-set rejection, and withmore » induced myocardial infarction of syngeneic heart grafts transplanted to normal and to sublethally irradiated recipients. Rejecting cardiac allografts transplanted to all reconstituted irradiated recipients were characterized by extensive infiltration with MRC OX8+ (T cytotoxic-suppressor, natural killer) cells even when this subset was virtually excluded from the reconstituting inocula. A similar proportional accumulation of MRC OX8+ cells observed at the infarct margins of syngeneic heart grafts transplanted to irradiated unreconstituted recipients greatly exceeded that present in normal nonirradiated controls. These data provide evidence that under conditions of heavy recipient irradiation, MRC OX8+ cells may be sequestered within heart grafts in response to nonspecific injury unrelated to the rejection process.« less

Micro-orientation control of silicon polymer thin films on graphite surfaces modified by heteroatom doping

NASA Astrophysics Data System (ADS)

Shimoyama, Iwao; Baba, Yuji; Hirao, Norie

2017-05-01

Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy is applied to study orientation structures of polydimethylsilane (PDMS) films deposited on heteroatom-doped graphite substrates prepared by ion beam doping. The Si K-edge NEXAFS spectra of PDMS show opposite trends of polarization dependence for non irradiated and N2+-irradiated substrates, and show no polarization dependence for an Ar+-irradiated substrate. Based on a theoretical interpretation of the NEXAFS spectra via first-principles calculations, we clarify that PDMS films have lying, standing, and random orientations on the non irradiated, N2+-irradiated, and Ar+-irradiated substrates, respectively. Furthermore, photoemission electron microscopy indicates that the orientation of a PDMS film can be controlled with microstructures on the order of μm by separating irradiated and non irradiated areas on the graphite surface. These results suggest that surface modification of graphite using ion beam doping is useful for micro-orientation control of organic thin films.

Application of the microbiological method DEFT/APC to detect minimally processed vegetables treated with gamma radiation

NASA Astrophysics Data System (ADS)

Araújo, M. M.; Duarte, R. C.; Silva, P. V.; Marchioni, E.; Villavicencio, A. L. C. H.

2009-07-01

Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent health effect. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and to inactivate food-borne pathogens. In combination with minimal processing it could improve safety and quality of MPV. A microbiological screening method based on the use of direct epifluorescent filter technique (DEFT) and aerobic plate count (APC) has been established for the detection of irradiated foodstuffs. The aim of this study was to evaluate the applicability of this technique in detecting MPV irradiation. Samples from retail markets were irradiated with 0.5 and 1.0 kGy using a 60Co facility. In general, with a dose increment, DEFT counts remained similar independent of the irradiation while APC counts decreased gradually. The difference of the two counts gradually increased with dose increment in all samples. It could be suggested that a DEFT/APC difference over 2.0 log would be a criteria to judge if a MPV was treated by irradiation. The DEFT/APC method could be used satisfactorily as a screening method for indicating irradiation processing.

Chemical sporulation and germination: cytoprotective nanocoating of individual mammalian cells with a degradable tannic acid-FeIII complex

NASA Astrophysics Data System (ADS)

Lee, Juno; Cho, Hyeoncheol; Choi, Jinsu; Kim, Doyeon; Hong, Daewha; Park, Ji Hun; Yang, Sung Ho; Choi, Insung S.

2015-11-01

Individual mammalian cells were coated with cytoprotective and degradable films by cytocompatible processes maintaining the cell viability. Three types of mammalian cells (HeLa, NIH 3T3, and Jurkat cells) were coated with a metal-organic complex of tannic acid (TA) and ferric ion, and the TA-FeIII nanocoat effectively protected the coated mammalian cells against UV-C irradiation and a toxic compound. More importantly, the cell proliferation was controlled by programmed formation and degradation of the TA-FeIII nanocoat, mimicking the sporulation and germination processes found in nature.Individual mammalian cells were coated with cytoprotective and degradable films by cytocompatible processes maintaining the cell viability. Three types of mammalian cells (HeLa, NIH 3T3, and Jurkat cells) were coated with a metal-organic complex of tannic acid (TA) and ferric ion, and the TA-FeIII nanocoat effectively protected the coated mammalian cells against UV-C irradiation and a toxic compound. More importantly, the cell proliferation was controlled by programmed formation and degradation of the TA-FeIII nanocoat, mimicking the sporulation and germination processes found in nature. Electronic supplementary information (ESI) available: Experimental details, LSCM images, and SEM and TEM images. See DOI: 10.1039/c5nr05573c

Solar irradiance dictates settlement timing and intensity of marine mussels

PubMed Central

Fuentes-Santos, Isabel; Labarta, Uxío; Álvarez-Salgado, X. Antón; Fernández-Reiriz, Mª José

2016-01-01

Identifying the environmental factors driving larval settlement processes is crucial to understand the population dynamics of marine invertebrates. This work aims to go a step ahead and predict larval presence and intensity. For this purpose we consider the influence of solar irradiance, wind regime and continental runoff on the settlement processes. For the first time, we conducted a 5-years weekly monitoring of Mytilus galloprovincialis settlement on artificial suspended substrates, which allowed us to search for interannual variability in the settlement patterns. Comparison between the seasonal pattern of larval settlement and solar irradiance, as well as the well-known effect of solar irradiance on water temperature and food availability, suggest that solar irradiance indirectly influences the settlement process, and support the use of this meteorological variable to predict settlement occurrence. Our results show that solar irradiance allows predicting the beginning and end of the settlement cycle a month in advance: Particularly we have observed that solar irradiance during late winter indirectly drives the timing and intensity of the settlement onset, Finally, a functional generalise additive model, which considers the influence of solar irradiance and continental runoff on the settlement process, provides an accurate prediction of settlement intensity a fortnight in advance. PMID:27384527

Solar irradiance dictates settlement timing and intensity of marine mussels

NASA Astrophysics Data System (ADS)

Fuentes-Santos, Isabel; Labarta, Uxío; Álvarez-Salgado, X. Antón; Fernández-Reiriz, Mª José

2016-07-01

Identifying the environmental factors driving larval settlement processes is crucial to understand the population dynamics of marine invertebrates. This work aims to go a step ahead and predict larval presence and intensity. For this purpose we consider the influence of solar irradiance, wind regime and continental runoff on the settlement processes. For the first time, we conducted a 5-years weekly monitoring of Mytilus galloprovincialis settlement on artificial suspended substrates, which allowed us to search for interannual variability in the settlement patterns. Comparison between the seasonal pattern of larval settlement and solar irradiance, as well as the well-known effect of solar irradiance on water temperature and food availability, suggest that solar irradiance indirectly influences the settlement process, and support the use of this meteorological variable to predict settlement occurrence. Our results show that solar irradiance allows predicting the beginning and end of the settlement cycle a month in advance: Particularly we have observed that solar irradiance during late winter indirectly drives the timing and intensity of the settlement onset, Finally, a functional generalise additive model, which considers the influence of solar irradiance and continental runoff on the settlement process, provides an accurate prediction of settlement intensity a fortnight in advance.

Evaluation of phototherapy in the differentiation of mesenchymal stem cells in the tissue repair of rats submitted to a hyperlipidemic diet

NASA Astrophysics Data System (ADS)

Oliveira, C. R. B.; Santos, L. S.; Silva, V. D. U.; Vitória, L. A.; Rodriguez, T. T.; Marques, A. M. C.; Xavier, F. C. A.; Ramalho, L.

2018-04-01

Obese people present a greater risk of developing other systemic diseases and comorbidities such as compromising the tissue repair process. Laser phototherapy can contribute to this repair by improving cellular functions, since stem cells may play an important role in repair due to their pluripotent potential. In this way, the influence of Laser Phototherapy (LP) was evaluated in the tissue repair of rats submitted to a hyperlipid diet through CD49 immunostaining for adipose stem cells. Forty-eight Wistar albinus rats were divided into two experimental groups: Standard Diet (SD) and Hyperlipid Diet (HD) for 20 weeks. After this period, excisional dorsal cutaneous wounds of 1 cm2 were made. The groups were subdivided into control and laser, the laser groups were irradiated (Diode Laser of Gallium and Aluminum Arsenide, λ660nm, 40mW, 6J / cm2) immediately after the surgery and every 48 hours. A group of rats were killed on day 7 and the other group on day 14 and the specimens processed by the immunohistochemical technique. The SD group presented antibodies marked with moderate to intense intensity, whereas in the HD group the weak staining for the time of 14 days prevailed. The irradiation protocol employed had no influence on the CD49 marker when compared to the control and irradiated groups over the same period. According to the methodology used and the results obtained it is concluded that laser light does not influence the recruitment of adipoderivative stem cells for the tissue repair process.

High doses of ionizing radiation on bone repair: is there effect outside the irradiated site?

PubMed

Rocha, Flaviana Soares; Dias, Pâmella Coelho; Limirio, Pedro Henrique Justino Oliveira; Lara, Vitor Carvalho; Batista, Jonas Dantas; Dechichi, Paula

2017-03-01

Local ionizing radiation causes damage to bone metabolism, it reduces blood supply and cellularity over time. Recent studies indicate that radiation promotes biological response outside the treatment field. The aim of this study was to investigate the effects of ionizing radiation on bone repair outside the irradiated field. Ten healthy male Wistar rats were used; and five animals were submitted to radiotherapy on the left femur. After 4 weeks, in all animals were created bone defects in the right and left femurs. Seven days after surgery, animals were euthanized. The femurs were removed and randomly divided into 3 groups (n=5): Control (C) (right femur of the non-irradiated animals); Local ionizing radiation (IR) (left femur of the irradiated animals); Contralateral ionizing radiation (CIR) (right femur of the irradiated animals). The femurs were processed and embedded in paraffin; and bone histologic sections were evaluated to quantify the bone neoformation. Histomorphometric analysis showed that there was no significant difference between groups C (24.6±7.04) and CIR (25.3±4.31); and IR group not showed bone neoformation. The results suggest that ionizing radiation affects bone repair, but does not interfere in bone repair distant from the primary irradiated site. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of different surface treatments on tensile bond strength of silicone-based soft denture liner.

PubMed

Akin, Hakan; Tugut, Faik; Mutaf, Burcu; Akin, Gulsah; Ozdemir, A Kemal

2011-11-01

Failure of the bond between the acrylic resin and resilient liner material is commonly encountered in clinical practice. The purpose of this study was to investigate the effect of different surface treatments (sandblasting, Er:YAG, Nd:YAG, and KTP lasers) on tensile bond strength of silicone-based soft denture liner. Polymethyl methacrylate test specimens were fabricated and each received one of eight surface treatments: untreated (control), sandblasted, Er:YAG laser irradiated, sandblasted + Er:YAG laser irradiated, Nd:YAG laser irradiated, sandblasted + Nd:YAG laser irradiated, KTP laser irradiated, and sandblasted + KTP laser irradiated. The resilient liner specimens (n = 15) were processed between two polymethyl methacrylate (PMMA) blocks. Bonding strength of the liners to PMMA were compared by tensile test with the use of a universal testing machine at a crosshead speed of 5 mm/min. Kruskal-Wallis and Wilcoxon tests were used to analyze the data (α = 0.05). Altering the polymethyl methacrylate surface by Er:YAG laser significantly increased the bond strengths in polymethyl methacrylate/silicone specimens, however, sandblasting before applying a lining material had a weakening effect on the bond. In addition, Nd:YAG and KTP lasers were found to be ineffective for increasing the strength of the bond.

Low-level laser therapy on skeletal muscle inflammation: evaluation of irradiation parameters

NASA Astrophysics Data System (ADS)

Mantineo, Matías; Pinheiro, João P.; Morgado, António M.

2014-09-01

We evaluated the effect of different irradiation parameters in low-level laser therapy (LLLT) for treating inflammation induced in the gastrocnemius muscle of rats through cytokines concentration in systemic blood and analysis of muscle tissue. We used continuous (830 and 980 nm) and pulsed illuminations (830 nm). Animals were divided into five groups per wavelength (10, 20, 30, 40, and 50 mW), and a control group. LLLT was applied during 5 days with a constant irradiation time and area. TNF-α, IL-1β, IL-2, and IL-6 cytokines were quantified by ELISA. Inflammatory cells were counted using microscopy. Identical methodology was used with pulsed illumination. Average power (40 mW) and duty cycle were kept constant (80%) at five frequencies (5, 25, 50, 100, and 200 Hz). For continuous irradiation, treatment effects occurred for all doses, with a reduction of TNF-α, IL-1β, and IL-6 cytokines and inflammatory cells. Continuous irradiation at 830 nm was more effective, a result explained by the action spectrum of cytochrome c oxidase (CCO). Best results were obtained for 40 mW, with data suggesting a biphasic dose response. Pulsed wave irradiation was only effective for higher frequencies, a result that might be related to the rate constants of the CCO internal electron transfer process.

Regulations on consume and commercialization of food irradiation in Mexico

NASA Astrophysics Data System (ADS)

Bustos Ramírez, Ma. Emilia; Jiménez Pérez, Jesús

1995-02-01

A Mexican standard for food irradiation is ready for final publication after the authority received and reviewed public comments of the project published in April 1994. The standard establish the radiation doses for different classes of food, based on ICGFI recommendations. Also included are controls for sampling, packaging, labelling, transportation, process inspection and accordance with international regulations. The results of the economical analysis of cost-benefit of the application of the standard show that the net present value is positive. The method of calculation is presented explaining the assumptions considered for the estimation of the total annual savings and surveillance costs. A final version of the research program report on radiation quarantine treatment of Mexican mangoes will be used for the petition to APHIS for the amendment of quarantine procedures to permit importation into the USA of irradiated products.

Effect of gamma irradiation on the microbial load, nutrient composition and free radical scavenging activity of Nelumbo nucifera rhizome

NASA Astrophysics Data System (ADS)

Khattak, Khanzadi Fatima; Simpson, Thomas James; Ihasnullah

2009-03-01

The assurance of microbial quality is necessary to make plant materials suitable for human consumption and commercialization. The aim of the present study was to evaluate the possibility to apply the gamma radiation treatment on the rhizome samples of Nelumbo nucifera for microbial decontamination. The radiation processing was carried out at dose levels of 1, 2, 4 and 6 kGy. The irradiated and control samples were analyzed for microbial load, organoleptic acceptance, extraction yield, proximate composition, phenolic contents and DPPH scavenging activity. The results indicated that gamma radiation treatment significantly reduced microbial load and increased the storability of the irradiated samples. The treated samples were also acceptable sensorically. The extraction yield and phenolic contents increased with the increase of radiation dose. Gamma radiation also enhanced the DPPH scavenging activity.

Effect of Panax ginseng saponins and Eleutherococcus senticosus on survival of cultured mammalian cells after ionizing radiation.

PubMed

Ben-Hur, E; Fulder, S

1981-01-01

Panax ginseng saponin and Eleutherococcus senticosus extract were applied to cells in culture in order to assess the effect of these substances on resistance to gamma-irradiation. Eleutherococcus was slightly radio protective. However, ginseng saponin at a dose of 10 microgram/ml was significantly radioprotective (Do = 2.25 Gy) compared to control (Do = 1.80 Gy) when it was present prior to gamma-irradiation. It enhanced radiation response if it was also present for 4-6 hours after gamma-irradiation (Do = 1.10 Gy). Ginseng-treated cells made 30% less RNA and 14% more protein during a 1 hour pulse of labeled intermediates. The cells were morphologically altered. It is concluded that ginseng saponin can increase radiation resistance. The effect is indirect, due to alterations in cell physiology rather than DNA repair processes.

Ferroelectric domain building blocks for photonic and nonlinear optical microstructures in LiNbO3

NASA Astrophysics Data System (ADS)

Zisis, G.; Ying, C. Y. J.; Soergel, E.; Mailis, S.

2014-03-01

The ability to manipulate the size and depth of poling inhibited domains, which are produced by UV laser irradiation of the +z face of lithium niobate crystals followed by electric field poling, is demonstrated. It is shown that complex domain structures, much wider than the irradiating laser spot, can be obtained by partially overlapping the subsequent UV laser irradiated tracks. The result of this stitching process is one uniform domain without any remaining trace of its constituent components thus increasing dramatically the utility of this method for the fabrication of surface microstructures as well as periodic and aperiodic domain lattices for nonlinear optical and surface acoustic wave applications. Finally, the impact of multi exposure on the domain characteristics is also investigated indicating that some control over the domain depth can be attained.

Food Irradiation Using Electron Beams and X-Rays

NASA Astrophysics Data System (ADS)

Miller, Bruce

2003-04-01

In this presentation we will discuss the technology of food irradiation using electron accelerators. Food irradiation has generally come to describe the use of ionizing radiation to decrease the population of, or prevent the growth of, undesirable biological organisms in food. The many beneficial applications include insect disinfestation, sprouting inhibition, delayed ripening, and the enhanced safety and sterilization of fresh and frozen meat products, seafood, and eggs. With special regard to food safety, bacteria such as Salmonella enteridis, Listeria monocytogenes, Campylobacter jejuni and Escherichia coli serotype O157:H7 are the primary causes of food poisoning in industrialized countries. Ionizing doses in the range of only 1-5 kilogray (kGy) can virtually eliminate these organisms from food, without affecting the food's sensory and nutritional qualities, and without inducing radioactivity. The key elements of an accelerator-based irradiation facility include the accelerator system, a scanning system, and a material handling system that moves the product through the beam in a precisely controlled manner. Extensive radiation shielding is necessary to reduce the external dose to acceptable levels, and a safety system is necessary to prevent accidental exposure of personnel during accelerator operation. Parameters that affect the dose distribution must be continuously monitored and controlled with process control software. The choice of electron beam vs x-ray depends on the areal density (density times thickness) of the product and the anticipated mass throughput. To eliminate nuclear activation concerns, the maximum kinetic energy of the accelerator is limited by regulation to 10 MeV for electron beams, and 5 MeV for x-rays. From penetration considerations, the largest areal density that can be treated by double-sided electron irradiation at 10 MeV is about 8.8 g/cm2. Products having greater areal densities must be processed using more penetrating x-rays. The mass throughput (dM/dt in kg/s) of an accelerator-based system is proportional to the average beam power (P in kW), and inversely proportional to the minimum required dose (Dm in kGy, with 1 kGy = 1 kJ/kg). The constant of proportionality is the mass throughput efficiency. Throughput efficiencies of 0.4 or better are typical of electron beam installations, but are only 0.025-0.035 for x-ray installations, primarily because of the inefficiency of bremsstrahlung generation at 5 MeV (about 8an axially-coupled, standing-wave, L-band linac with an average power in excess of 100 kW to achieve reasonable throughput rates with x-ray processing. Various design aspects of this new machine will be presented.

IL-6 Mediates Macrophage Infiltration after Irradiation via Up-regulation of CCL2/CCL5 in Non-small Cell Lung Cancer.

PubMed

Wang, Xin; Yang, Xiaodong; Tsai, Ying; Yang, Li; Chuang, Kuang-Hsiang; Keng, Peter C; Lee, Soo Ok; Chen, Yuhchyau

2017-01-01

Radiotherapy is effective in reducing primary tumors, however, it may enhance macrophage infiltration to tumor sites, accelerating tumor progression in several ways. We investigated whether radiation can increase macrophage infiltration into non-small cell lung carcinoma (NSCLC) cells. Analysis of in vitro macrophage (differentiated THP-1 cells) migration to either nonirradiated or irradiated tumor cells showed increased migration to the irradiated tumor cells. Because the IL-6 levels in A549 and H157 cells were significantly increased after irradiation, we then investigated whether this increased IL-6 level contributes to radiation-induced macrophage migration. Radiation-induced macrophage infiltration was reduced when IL-6 was knocked down in tumor cells, indicating a positive IL-6 role in this process. To validate this in vitro result, an orthotopic mouse model was developed using a luciferase-tagged H157siIL-6/scramble control (sc) cell set. After tumors developed, the lungs were irradiated, and infiltration of endogenous macrophages and tail-vein injected fluorescent macrophages to tumor sites was investigated. In both groups, increased macrophage infiltration was observed in H157sc cell-derived xenografts compared to H157siIL-6 cell-derived xenografts, confirming the positive IL-6 role in the radiation-induced macrophage infiltration process. In mechanistic dissection studies, radiation-induced up-regulation of CCL2 and CCL5 by IL-6 was detected, and blocking the action of CCL2/CCL5 molecules significantly reduced the number of migrated macrophages to tumor cells after irradiation. These results demonstrate that targeting the IL-6 signaling or CCL2/CCL5 molecules in combination with conventional radiotherapy potentially blocks undesired radiation-induced macrophage infiltration.

Degradation of carbendazim in water via photo-Fenton in Raceway Pond Reactor: assessment of acute toxicity and transformation products.

PubMed

da Costa, Elizângela Pinheiro; Bottrel, Sue Ellen C; Starling, Maria Clara V M; Leão, Mônica M D; Amorim, Camila Costa

2018-05-08

This study aimed at investigating the degradation of fungicide carbendazim (CBZ) via photo-Fenton reactions in artificially and solar irradiated photoreactors at laboratory scale and in a semi-pilot scale Raceway Pond Reactor (RPR), respectively. Acute toxicity was monitored by assessing the sensibility of bioluminescent bacteria (Aliivibrio fischeri) to samples taken during reactions. In addition, by-products formed during solar photo-Fenton were identified by liquid chromatography coupled to mass spectrometry (UFLC-MS). For tests performed in lab-scale, two artificial irradiation sources were compared (UV λ > 254nm and UV-Vis λ > 320nm ). A complete design of experiments was performed in the semi-pilot scale RPR in order to optimize reaction conditions (Fe 2+ and H 2 O 2 concentrations, and water depth). Efficient degradation of carbendazim (> 96%) and toxicity removal were achieved via artificially irradiated photo-Fenton under both irradiation sources. Control experiments (UV photolysis and UV-Vis peroxidation) were also efficient but led to increased acute toxicity. In addition, H 2 O 2 /UV λ > 254nm required longer reaction time (60 minutes) when compared to the photo-Fenton process (less than 1 min). While Fenton's reagent achieved high CBZ and acute toxicity removal, its efficiency demands higher concentration of reagents in comparison to irradiated processes. Solar photo-Fenton removed carbendazim within 15 min of reaction (96%, 0.75 kJ L -1 ), and monocarbomethoxyguanidine, benzimidazole isocyanate, and 2-aminobenzimidazole were identified as transformation products. Results suggest that both solar photo-Fenton and artificially irradiated systems are promising routes for carbendazim degradation.

Effect of gamma irradiation on the color, structure and morphology of nickel-doped polyvinyl alcohol films: Alternative use as dosimeter or irradiation indicator

NASA Astrophysics Data System (ADS)

Raouafi, A.; Daoudi, M.; Jouini, K.; Charradi, K.; Hamzaoui, A. H.; Blaise, P.; Farah, K.; Hosni, F.

2018-06-01

Nickel-doped poly vinyl alcohol (PVA) films were developed for potential application in industrial sectors like radiation processing. We report in this paper the results of an experimental investigation of 60Co source γ-radiation effect on colorimetric, structural and morphological properties of PVA films doped with 0.5% Ni2+ ions (PVA/Ni2+). The PVA/Ni2+ films were irradiated by different gamma-radiation doses varying from 5 to 100 kGy. Color modification of films were studied using L∗, a∗ and b∗ color space measurements as function of the γ-dose and post-irradiation time. The visual change in all samples was verified by microstructure analysis, Fourier transforms infrared (FTIR) spectroscopy, X-Rays diffraction (XRD) and scanning electron microscopy (SEM). The color space exhibited a linear dose response at a dose ranging from 5 to 50 kGy, and then it reached saturation for higher γ-doses. The calculated color changes (ΔE) show a linear dose response relationship from 9.90 to 115.02 in the dose range from 0 to 50 kGy. It showed also the activation of stable color centers. The variability of the color change did not exceed 3% during 80 h (h) post-irradiation. Furthermore, the microstructure analysis evidenced that the color modification due to the optical activation of nickel-oxide (NiO) color center were obtained by complexing Ni2+ ions in irradiated PVA films. The obtained results inspire the possibility to use PVA films for the control process in industrial radiation facilities in dose range 5-50 kGy.

EXTENSION OF STORAGE LIFE OF GARLIC BULBS BY $gamma$-IRRADIATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathur, P.B.

1963-12-01

Garlic bulbs were packaged in polyethylene bags and irradiated with 5 krad of Co/sup 60/ gamma rays. Irradiated and control bulbs were stored at 11- 12 deg C. Weight loss, number of bulbs sprouted, and number of bulbs decayed were greater in the control group than in the irradiated group. No adverse effect on the taste, flavor, texture, or pungency of irradiated garlic bulbs was determined organo-leptically at the end of seven months storage. (H.M.G.)

Impact of γ-rays on seed germination/short-term storage in four native alpine species: Correlation with free radical and antioxidant profiles

NASA Astrophysics Data System (ADS)

Zani, Deborah; Dondi, Daniele; Araújo, Susana; Mondoni, Andrea; Balestrazzi, Alma

2017-02-01

In this study, the impact of gamma (γ) radiation on seeds was investigated in four native alpine species, Campanula barbata L., Cirsium spinosissinum (L.) Scop., Plantago alpina L., and Silene vulgaris (Moench) Garcke. Seeds were γ-irradiated with 100 and 200 Gy total doses delivered at a high dose rate of 2.7 Gy min-1. Irradiated and non-irradiated seeds were used immediately, and subsequently 7 and 14 days after drying (15% Relative Humidity, 15 °C) to assess their response to standard seed bank processing. Germination rates, seedling length and weight, antioxidant activity and phenolics content were measured, while free radical accumulation profiles were acquired by electron paramagnetic resonance (EPR). Germination was only hampered in irradiated C. barbata seeds. C. barbata and C. spinosissinum seedlings obtained from irradiated seeds suffered a decrease in length and weight, while growth was not affected in P. alpina and S. vulgaris, when compared to non-irradiated control. Although profiles of seed antioxidant activity were not influenced immediately after γ-irradiation, subsequent drying under seed bank standards induced changes in seed antioxidant activity, depending on the species. According to EPR data, C. barbata and C. Spinosissinum seeds revealed high free radical levels in non-irradiated samples, which were further enhanced by γ-irradiation. An opposite behaviour was observed in P. alpina and S. vulgaris. The four alpine species showed different profiles of γ-ray sensitivity. The reported data encourage future research to test inter-specific variability in the plant response to γ-rays based on a multidisciplinary approach which integrates environmental data. Considering that seeds of alpine plants are short-lived in storage, γ-irradiation could emerge as a promissory priming tool for native endangered species.

In vivo analysis of THz wave irradiation induced acute inflammatory response in skin by laser-scanning confocal microscopy.

PubMed

Hwang, Yoonha; Ahn, Jinhyo; Mun, Jungho; Bae, Sangyoon; Jeong, Young Uk; Vinokurov, Nikolay A; Kim, Pilhan

2014-05-19

The recent development of THz sources in a wide range of THz frequencies and power levels has led to greatly increased interest in potential biomedical applications such as cancer and burn wound diagnosis. However, despite its importance in realizing THz wave based applications, our knowledge of how THz wave irradiation can affect a live tissue at the cellular level is very limited. In this study, an acute inflammatory response caused by pulsed THz wave irradiation on the skin of a live mouse was analyzed at the cellular level using intravital laser-scanning confocal microscopy. Pulsed THz wave (2.7 THz, 4 μs pulsewidth, 61.4 μJ per pulse, 3Hz repetition), generated using compact FEL, was used to irradiate an anesthetized mouse's ear skin with an average power of 260 mW/cm(2) for 30 minutes using a high-precision focused THz wave irradiation setup. In contrast to in vitro analysis using cultured cells at similar power levels of CW THz wave irradiation, no temperature change at the surface of the ear skin was observed when skin was examined with an IR camera. To monitor any potential inflammatory response, resident neutrophils in the same area of ear skin were repeatedly visualized before and after THz wave irradiation using a custom-built laser-scanning confocal microscopy system optimized for in vivo visualization. While non-irradiated control skin area showed no changes in the number of resident neutrophils, a massive recruitment of newly infiltrated neutrophils was observed in the THz wave irradiated skin area after 6 hours, which suggests an induction of acute inflammatory response by the pulsed THz wave irradiation on the skin via a non-thermal process.

Photobiomodulation laser improves the early repair process of hypothyroid rats

NASA Astrophysics Data System (ADS)

Uzêda e Silva, V. D.; Rodriguez, T. T.; Xavier, F. C. A.; dos Santos, J. N.; Vasconcelos, R. M.; Ramalho, L. M. P.

2018-04-01

Delay in wound healing has been observed in the hypothyroidism disfunction. Laser light can modulate various biological phenomena acting on different cell types. However, there are few reports in the literature regarding the effects of laser on wound healing of hypothyroid models. This study aimed to evaluate the differences in reepithelialization process of cutaneous wounds on hypothyroid and euthyroid rats treated with laser phototherapy. Forty-eight rats were divided into two main groups: euthyroid (EU) and hypothyroid (HYPO). Hypothyroidism was induced by Thyroidectomy. Each group was divided into subgroups: control (without laser) and laser groups. Standard surgical wound was created on the dorsum of each rat. The irradiation protocols (λ660 nm, 40 mW, CW; 10 J/cm2) was carried out immediately after wounding and repeated every 24h during 3 and 7 days. After animal death, specimens were taken, routinely processed, cut, stained with hematoxylin-eosin, and underwent histological analysis. Three days after the surgery, it was possible to observe initial reepithelialization in more advanced stages in the wound area of the irradiated hypothyroid group when compared to control hypothyroid group (p<0.05). No significant difference was found in the experimental period of 7 days among the groups. It was concluded that the laser light did influence reepithelialization process on hypothyroid rats in early stages of healing process.

The Impact of Gamma Radiation on Sediment Microbial Processes

PubMed Central

Brown, Ashley R.; Boothman, Christopher; Pimblott, Simon M.

2015-01-01

Microbial communities have the potential to control the biogeochemical fate of some radionuclides in contaminated land scenarios or in the vicinity of a geological repository for radioactive waste. However, there have been few studies of ionizing radiation effects on microbial communities in sediment systems. Here, acetate and lactate amended sediment microcosms irradiated with gamma radiation at 0.5 or 30 Gy h−1 for 8 weeks all displayed NO3− and Fe(III) reduction, although the rate of Fe(III) reduction was decreased in 30-Gy h−1 treatments. These systems were dominated by fermentation processes. Pyrosequencing indicated that the 30-Gy h−1 treatment resulted in a community dominated by two Clostridial species. In systems containing no added electron donor, irradiation at either dose rate did not restrict NO3−, Fe(III), or SO42− reduction. Rather, Fe(III) reduction was stimulated in the 0.5-Gy h−1-treated systems. In irradiated systems, there was a relative increase in the proportion of bacteria capable of Fe(III) reduction, with Geothrix fermentans and Geobacter sp. identified in the 0.5-Gy h−1 and 30-Gy h−1 treatments, respectively. These results indicate that biogeochemical processes will likely not be restricted by dose rates in such environments, and electron accepting processes may even be stimulated by radiation. PMID:25841009

Laboratory photochemical processing of aqueous aerosols: formation and degradation of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls

NASA Astrophysics Data System (ADS)

Pavuluri, C. M.; Kawamura, K.; Mihalopoulos, N.; Swaminathan, T.

2015-07-01

To better understand the photochemical processing of dicarboxylic acids and related polar compounds, we conducted batch UV irradiation experiments on two types of aerosol samples collected from India, which represent anthropogenic (AA) and biogenic (BA) aerosols, for time periods of 0.5 to 120 h. The irradiated samples were analyzed for molecular compositions of diacids, oxoacids and α-dicarbonyls. The results show that photochemical degradation of oxalic (C2), malonic (C3) and other C8-C12 diacids overwhelmed their production in aqueous aerosols, whereas succinic acid (C4) and C5-C7 diacids showed a significant increase (ca. 10 times) during the course of irradiation experiments. The photochemical formation of oxoacids and α-dicarbonyls overwhelmed their degradation during the early stages of experiment except for ω-oxooctanoic acid (ωC8), which showed a similar pattern to that of C4. We also found a gradual decrease in the relative abundance of C2 to total diacids and an increase in the relative abundance of C4 during prolonged experiment. Based on the changes in concentrations and mass ratios of selected species with the irradiation time, we hypothesize that iron-catalyzed photolysis of C2 and C3 diacids controls their concentrations in Fe-rich atmospheric waters, whereas photochemical formation of C4 diacid (via ωC8) is enhanced with photochemical processing of aqueous aerosols in the atmosphere. This study demonstrates that the ambient aerosols contain abundant precursors that produce diacids, oxoacids and α-dicarbonyls, although some species such as oxalic acid decompose extensively during an early stage of photochemical processing.

Treating cell culture media with UV irradiation against adventitious agents: minimal impact on CHO performance.

PubMed

Yen, Sandi; Sokolenko, Stanislav; Manocha, Bhavik; Blondeel, Eric J M; Aucoin, Marc G; Patras, Ankit; Daynouri-Pancino, Farnaz; Sasges, Michael

2014-01-01

Sterility of cell culture media is an important concern in biotherapeutic processing. In large scale biotherapeutic production, a unit contamination of cell culture media can have costly effects. Ultraviolet (UV) irradiation is a sterilization method effective against bacteria and viruses while being non-thermal and non-adulterating in its mechanism of action. This makes UV irradiation attractive for use in sterilization of cell culture media. The objective of this study was to evaluate the effect of UV irradiation of cell culture media in terms of chemical composition and the ability to grow cell cultures in the treated media. The results showed that UV irradiation of commercial cell culture media at relevant disinfection doses impacted the chemical composition of the media with respect to several carboxylic acids, and to a minimal extent, amino acids. The cumulative effect of these changes, however, did not negatively influence the ability to culture Chinese Hamster Ovary cells, as evaluated by cell viability, growth rate, and protein titer measurements in simple batch growth compared with the same cells cultured in control media exposed to visible light. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers.

Position of the American Dietetic Association: food irradiation.

PubMed

Wood, O B; Bruhn, C M

2000-02-01

Food irradiation has been identified a sa safe technology to reduce the risk of foodborne illness as part of high-quality food production, processing, handling, and preparation. Food irradiation's history of scientific research , evaluation, and testing spans more than 40 countries around the world and it has been endorsed or support by numerous national and international food and organizations and professional groups. Food irradiation utilizes a source of ionizing energy that passes through food to destroy harmful bacteria and other organism. Often referred to as "cold pasteurization," food irradiation offers negligible loss of nutrients or sensory qualities in food as it does not substantially raise the temperature of the food during processing. Food irradiation does not replace proper food production, processing, handling, or preparation, nor can it enhance the quality of or prevent contact with foodborne bacteria after irradiation. In the United States, manufacturers are required to identify irradiated food sold to consumers with an international symbol (Radura) and and terminology describing the process on product labels. In addiction, food irradiation facilities are thoroughly regulated and monitored for worker and environmental safety. Members of The American Dietetic Association (ADA) and other food, nutrition, and health professionals have a responsibility to educate consumers, food processors, manufacturers and retailers about the safety and application of the technology. When consumers are educated about food irradiation, many prefer irradiated products because of their increased safety. It is the position of ADA that food irradiation enhances the safety and quality of the food supply and helps protect consumers from foodborne illness. The ADA encourages the government, food manufactures, food commodity groups, and qualified food and nutrition professionals to work together to educate consumers about this additional food safety tool and make this choice available in the marketplace.

Anisotropic pyrochemical microetching of poly(tetrafluoroethylene) initiated by synchrotron radiation-induced scission of molecule bonds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamaguchi, Akinobu, E-mail: yamaguti@lasti.u-hyogo.ac.jp, E-mail: utsumi@lasti.u-hyogo.ac.jp; Kido, Hideki; Utsumi, Yuichi, E-mail: yamaguti@lasti.u-hyogo.ac.jp, E-mail: utsumi@lasti.u-hyogo.ac.jp

2016-02-01

We developed a process for micromachining polytetrafluoroethylene (PTFE): anisotropic pyrochemical microetching induced by synchrotron X-ray irradiation. X-ray irradiation was performed at room temperature. Upon heating, the irradiated PTFE substrates exhibited high-precision features. Both the X-ray diffraction peak and Raman signal from the irradiated areas of the substrate decreased with increasing irradiation dose. The etching mechanism is speculated as follows: X-ray irradiation caused chain scission, which decreased the number-average degree of polymerization. The melting temperature of irradiated PTFE decreased as the polymer chain length decreased, enabling the treated regions to melt at a lower temperature. The anisotropic pyrochemical etching process enabledmore » the fabrication of PTFE microstructures with higher precision than simultaneously heating and irradiating the sample.« less

Highly Controlled Codeposition Rate of Organolead Halide Perovskite by Laser Evaporation Method.

PubMed

Miyadera, Tetsuhiko; Sugita, Takeshi; Tampo, Hitoshi; Matsubara, Koji; Chikamatsu, Masayuki

2016-10-05

Organolead-halide perovskites can be promising materials for next-generation solar cells because of its high power conversion efficiency. The method of precise fabrication is required because both solution-process and vacuum-process fabrication of the perovskite have problems of controllability and reproducibility. Vacuum deposition process was expected to achieve precise control; however, vaporization of amine compound significantly degrades the controllability of deposition rate. Here we achieved the reduction of the vaporization by implementing the laser evaporation system for the codeposition of perovskite. Locally irradiated continuous-wave lasers on the source materials realized the reduced vaporization of CH 3 NH 3 I. The deposition rate was stabilized for several hours by adjusting the duty ratio of modulated laser based on proportional-integral control. Organic-photovoltaic-type perovskite solar cells were fabricated by codeposition of PbI 2 and CH 3 NH 3 I. A power-conversion efficiency of 16.0% with reduced hysteresis was achieved.

Infectivity and egg production of Nematospiroides dubius as affected by space flight and ultraviolet irradiation

NASA Technical Reports Server (NTRS)

Long, R. A.; Ellis, W. L.; Taylor, G. R.

1973-01-01

Nematospiroides dubius was tested to determine the infective potential of the third stage larvae and the egg-production and egg-viability rates of the resulting adults after they are exposed to space flight and solar ultraviolet irradiation. The results are indicative that space-flown larvae exposed to solar ultraviolet irradiation were rendered noninfective in C57 mice, whereas flight control larvae that received no solar ultraviolet irradiation matured at the same rate as the ground control larvae. However, depressed egg viability was evident in the flight control larvae.

THE INFLUENCE OF ANTITUBERCULOUS VACCINATION ON THE COURSE OF THE TUBERCULOUS PROCESS IN CHRONIC IRRADIATION (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khudushina, T.A.

1961-10-01

Preliminary antituberculosis vaccination of tuberculosisinfected rabbits subjected to protracted x irradiation (10 r daily) yields a positive effect only during the first stages of irradiation. Disturbance of specific antituberculous immunity occurs in the process of development of chronic radiation sickness. At this period the tuberculous process acquires a marked exudative-necrotic character. (auth)

Association of Diet With Skin Histological Features in UV-B-Exposed Mice.

PubMed

Bhattacharyya, Tapan K; Hsia, Yvonne; Weeks, David M; Dixon, Tatiana K; Lepe, Jessica; Thomas, J Regan

2017-09-01

Long-term exposure to solar radiation produces deleterious photoaging of the skin. It is not known if diet can influence skin photoaging. To study the influence of a calorie-restricted diet and an obesity diet in mice exposed to long-term UV-B irradiation to assess if there is an association between diet and histopathological response to UV-B irradiation. In this animal model study in an academic setting, the dorsal skin of SKH1 hairless mice receiving normal, calorie-restricted, and obesity diets was exposed to UV-B irradiation 3 times a week for 10 weeks and were compared with corresponding controls. The mice were placed in the following groups, with 8 animals in each group: (1) intact control (C) with regular diet and no UV-B exposure, (2) intact control with UV-B exposure (CR), (3) calorie-restricted diet (CrC), (4) calorie-restricted diet with UV-B exposure (CrR), (5) obesity diet (OC), and (6) obesity diet with UV-B exposure (OR). The experiment was conducted during October through December 2013. Tissue processing and histological analysis were completed in 2016. Histomorphometric analysis was performed on paraffin-embedded skin sections stained by histological and immunohistochemical methods for estimation of epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, mast cells, dermal cellularity, and adipose layer ratio. Changes in wrinkles were noted. Hairless female mice (age range, 6-8 weeks) were obtained. With a normal diet, changes from UV-B irradiation occurred in epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, and mast cells, which were modestly influenced by an obesity diet. Calorie restriction influenced the skin in nonirradiated control animals, with higher values for most variables. After UV-B exposure in animals with calorie restriction, epidermal thickness was increased, but other variables were unaffected. Animals receiving the calorie-restricted diet lost weight when exposed to long-term UV-B irradiation. Wrinkles were reduced in the calorie-restricted control group and in UV-B-exposed animals who received the obesity diet. Dietary alterations seem to modify histopathological responses to UV-B exposure in the skin of hairless mice. NA.

Regional Nodal Irradiation in Early-Stage Breast Cancer.

PubMed

Whelan, Timothy J; Olivotto, Ivo A; Parulekar, Wendy R; Ackerman, Ida; Chua, Boon H; Nabid, Abdenour; Vallis, Katherine A; White, Julia R; Rousseau, Pierre; Fortin, Andre; Pierce, Lori J; Manchul, Lee; Chafe, Susan; Nolan, Maureen C; Craighead, Peter; Bowen, Julie; McCready, David R; Pritchard, Kathleen I; Gelmon, Karen; Murray, Yvonne; Chapman, Judy-Anne W; Chen, Bingshu E; Levine, Mark N

2015-07-23

Most women with breast cancer who undergo breast-conserving surgery receive whole-breast irradiation. We examined whether the addition of regional nodal irradiation to whole-breast irradiation improved outcomes. We randomly assigned women with node-positive or high-risk node-negative breast cancer who were treated with breast-conserving surgery and adjuvant systemic therapy to undergo either whole-breast irradiation plus regional nodal irradiation (including internal mammary, supraclavicular, and axillary lymph nodes) (nodal-irradiation group) or whole-breast irradiation alone (control group). The primary outcome was overall survival. Secondary outcomes were disease-free survival, isolated locoregional disease-free survival, and distant disease-free survival. Between March 2000 and February 2007, a total of 1832 women were assigned to the nodal-irradiation group or the control group (916 women in each group). The median follow-up was 9.5 years. At the 10-year follow-up, there was no significant between-group difference in survival, with a rate of 82.8% in the nodal-irradiation group and 81.8% in the control group (hazard ratio, 0.91; 95% confidence interval [CI], 0.72 to 1.13; P=0.38). The rates of disease-free survival were 82.0% in the nodal-irradiation group and 77.0% in the control group (hazard ratio, 0.76; 95% CI, 0.61 to 0.94; P=0.01). Patients in the nodal-irradiation group had higher rates of grade 2 or greater acute pneumonitis (1.2% vs. 0.2%, P=0.01) and lymphedema (8.4% vs. 4.5%, P=0.001). Among women with node-positive or high-risk node-negative breast cancer, the addition of regional nodal irradiation to whole-breast irradiation did not improve overall survival but reduced the rate of breast-cancer recurrence. (Funded by the Canadian Cancer Society Research Institute and others; MA.20 ClinicalTrials.gov number, NCT00005957.).

Large-area one-step assembly of three-dimensional porous metal micro/nanocages by ethanol-assisted femtosecond laser irradiation for enhanced antireflection and hydrophobicity.

PubMed

Li, Guoqiang; Li, Jiawen; Zhang, Chenchu; Hu, Yanlei; Li, Xiaohong; Chu, Jiaru; Huang, Wenhao; Wu, Dong

2015-01-14

The capability to realize 2D-3D controllable metallic micro/nanostructures is of key importance for various fields such as plasmonics, electronics, bioscience, and chemistry due to unique properties such as electromagnetic field enhancement, catalysis, photoemission, and conductivity. However, most of the present techniques are limited to low-dimension (1D-2D), small area, or single function. Here we report the assembly of self-organized three-dimensional (3D) porous metal micro/nanocages arrays on nickel surface by ethanol-assisted femtosecond laser irradiation. The underlying formation mechanism was investigated by a series of femtosecond laser irradiation under exposure time from 5 to 30 ms. We also demonstrate the ability to control the size of micro/nanocage arrays from 0.8 to 2 μm by different laser pulse energy. This method features rapidness (∼10 min), simplicity (one-step process), and ease of large-area (4 cm(2) or more) fabrication. The 3D cagelike micro/nanostructures exhibit not only improved antireflection from 80% to 7% but also enhanced hydrophobicity from 98.5° to 142° without surface modification. This simple technique for 3D large-area controllable metal microstructures will find great potential applications in optoelectronics, physics, and chemistry.

Controllable Si (100) micro/nanostructures by chemical-etching-assisted femtosecond laser single-pulse irradiation

NASA Astrophysics Data System (ADS)

Li, Xiaowei; Xie, Qian; Jiang, Lan; Han, Weina; Wang, Qingsong; Wang, Andong; Hu, Jie; Lu, Yongfeng

2017-05-01

In this study, silicon micro/nanostructures of controlled size and shape are fabricated by chemical-etching-assisted femtosecond laser single-pulse irradiation, which is a flexible, high-throughput method. The pulse fluence is altered to create various laser printing patterns for the etching mask, resulting in the sequential evolution of three distinct surface micro/nanostructures, namely, ring-like microstructures, flat-top pillar microstructures, and spike nanostructures. The characterized diameter of micro/nanostructures reveals that they can be flexibly tuned from the micrometer (˜2 μm) to nanometer (˜313 nm) scales by varying the laser pulse fluence in a wide range. Micro-Raman spectroscopy and transmission electron microscopy are utilized to demonstrate that the phase state changes from single-crystalline silicon (c-Si) to amorphous silicon (a-Si) after single-pulse femtosecond laser irradiation. This amorphous layer with a lower etching rate then acts as a mask in the wet etching process. Meanwhile, the on-the-fly punching technique enables the efficient fabrication of large-area patterned surfaces on the centimeter scale. This study presents a highly efficient method of controllably manufacturing silicon micro/nanostructures with different single-pulse patterns, which has promising applications in the photonic, solar cell, and sensors fields.

Preliminary study of the effect of gamma irradiation on the vase life of Iridaceae Hollandica

NASA Astrophysics Data System (ADS)

Dennis, S.; Fisher, L.; Ware, C.; Giraldo, C. H. C.

2018-03-01

The vase life of irises (Iridaceae Hollandica 'Telstar') was determined before and after gamma irradiation in the Missouri S&T Research Reactor (MSTR) at 20, 80, 457, 1060, and 1473 Gy. It was determined that vase life improves by as much as 7% for the 20 Gy irradiation. At about 100 Gy the vase life is comparable to non-irradiated flowers. Unfortunately pest control requires 200-300 Gy. At 457 Gy the vase life is about 15% shorter, and it gets worse at higher doses (30% lower vase life at 1 kGy). Gamma irradiation of irises can be a viable method of pest control, but the irradiation dose should be kept as low as possible while still achieving the phytosanitary objectives depending on the type of pest to control.

Fabrication of (U,Am)O2 pellet with controlled porosity from oxide microspheres

NASA Astrophysics Data System (ADS)

Ramond, Laure; Coste, Philippe; Picart, Sébastien; Gauthé, Aurélie; Bataillea, Marc

2017-08-01

U1-xAmxO2±δ mixed-oxides are considered as promising compounds for americium heterogeneous transmutation in Sodium Fast Neutron Reactor. Porous microstructure is envisaged in order to facilitate helium and fission gas release and to reduce pellet swelling during irradiation and under self-irradiation. In this study, the porosity is created by reducing (U,Am)3O8 microspheres into (U,Am)O2 during the sintering. This reduction is accompanied by a decrease of the lattice volume that leads to the creation of open porosity. Finally, an (U0.90Am0.10)O2 porous ceramic pellet (D∼89% of the theoretical density TD) with controlled porosity (≥8% open porosity) was obtained from mixed-oxide microspheres obtained by the Weak Acid Resin (WAR) process.

Effects of irradiation of feed ingredients added to meal or pelleted diets on growth performance of weanling pigs.

PubMed

Groesbeck, C N; Derouchey, J M; Tokach, M D; Goodband, R D; Dritz, S S; Nelssen, J L

2009-12-01

Two experiments were conducted to evaluate the effects of irradiated ingredients in meal and pelleted diets on nursery pig performance. In Exp. 1, a total of 192 pigs (initial BW, 6.0 kg) were used in a 25-d experiment. Pigs were blocked by BW and randomly allotted in a 2 x 2 factorial arrangement of treatments with main effects of diet form (meal or pellet) and either irradiated (11.92 kGy) or nonirradiated spray-dried animal plasma (SDAP). Irradiated SDAP had less total bacterial amounts than nonirradiated SDAP, and pelleted diets also had less bacterial amounts than diets in meal form. However, the complete diets with and without irradiated SDAP had similar bacterial concentrations. There was a diet form x SDAP irradiation interaction (P < 0.05) for ADG from d 0 to 11 and d 0 to 25. Pigs fed irradiated SDAP in meal form had increased ADG compared with pigs fed the nonirradiated meal diet, with no change in ADG of pigs fed pelleted diets. In addition, from d 0 to 11, pigs fed irradiated SDAP or pelleted diets had greater G:F (P < 0.01) compared with pigs fed regular SDAP and meal diets, respectively. In Exp. 2, a total of 350 pigs (initial BW, 4.9 kg) were used in a 22-d experiment to determine the effects of feeding irradiated protein sources (SDAP, soybean meal, fish meal, or all 3) in meal and pellet diets on pig performance. Pigs were blocked by BW and randomly allotted to 1 of 10 treatments consisting of a single diet formulation fed in either meal or pellet form containing either no irradiated protein sources or irradiated SDAP, soybean meal, fish meal, or all 3 irradiated protein sources (10.20 kGy). Irradiated SDAP, soybean meal, and fish meal tended to have reduced total bacterial concentrations compared with nonirradiated plasma, and pelleted diets had reduced bacterial concentrations compared with diets in meal form. No irradiation x diet form interactions (P > 0.16) were observed. From d 0 to 11, pigs fed diets containing irradiated protein sources had greater (P < 0.03) G:F compared with pigs fed the control diets, with no difference in ADG or ADFI. From d 0 to 11, and overall (d 0 to 22), pigs fed pellet diets had greater G:F (P < 0.01) compared with pigs fed meal diets, with no difference in ADG and ADFI. These studies indicate that both irradiation and pelleting are manufacturing processes that can reduce bacteria concentrations in feed ingredients and diets. Irradiated SDAP, soybean meal, and fish meal improved G:F compared with control diets containing nonirradiated ingredients. Furthermore, pigs fed pelleted diets had increased G:F compared with pigs fed meal diets.

Effects of irradiation and semistarvation on rat thyrotropin beta subunit messenger ribonucleic acid, pituitary thyrotropin content, and thyroid hormone levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Litten, R.Z.; Carr, F.E.; Fein, H.G.

1990-01-01

The effect of radiation-induced anorexia on serum thyrotropin (TSH), pituitary TSH-{beta} mRNA, pituitary TSH content, serum thyroxine (T{sub 4}), and serum 3,5,3{prime}-triiodothyronine (T{sub 3}) was investigated using feed-matched controls. Rats received 10 Gy gamma whole-body irradiation and were examined 1-3 days postirradiation. Feed-matched and untreated controls were also studied. The average food intake of the irradiated and feed-matched groups was approximately 18% of the untreated controls. Over the three day period both the irradiated and feed-matched groups lost a significant amount of body weight. The serum T{sub 4} levels of both the irradiated and feed-matched groups were not significantly differentmore » from each other, but were significantly depressed when compared to the untreated control group. The serum TSH and T{sub 3} were, however, significantly greater in the irradiated than the feed-matched groups at day 3 posttreatment. To determine if the difference in the serum TSH level between the two groups was due to a pretranslational alteration in TSH production, we measured the TSH-{beta} mRNA using an RNA blot hybridization assay. We found that the TSH-{beta} mRNA level was the same in the irradiated and feed-matched groups, suggesting that the mechanism responsible for the radiation-induced increase in the serum TSH level is posttranscriptional. Pituitary TSH content in the irradiated rats was significantly less than in pair-fed controls, suggesting that irradiation may permit enhanced secretion of stored hormone.« less

Method and apparatus for controlled size distribution of gel microspheres formed from aqueous dispersions

DOEpatents

Ryon, Allen D.; Haas, Paul A.; Vavruska, John S.

1984-01-01

The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.

Molecular Determinants of Radioresponse in Prostate Cancer

DTIC Science & Technology

2002-08-01

SECURITY CLASSIFICATION OF ABSTRACT Unclassified 15. NUMBER OF PAGES 72 16. PRICE CODE 20. LIMITATION OF ABSTRACT Unlimited Standard Form...irradiated LNCaP cells; right panel, irradiated RAT-1 HO 15.19 positive control cells (magnification lOOOx); (b) Time course of IR-induced apoptosis... right ) at 5 days post-irradiation following doses of OGy (control, mock- irradiated), 2Gy and lOGy. Shown is a representative experiment with total cell

Inverse Analysis of Irradiated NuclearMaterial Gamma Spectra via Nonlinear Optimization

NASA Astrophysics Data System (ADS)

Dean, Garrett James

Nuclear forensics is the collection of technical methods used to identify the provenance of nuclear material interdicted outside of regulatory control. Techniques employed in nuclear forensics include optical microscopy, gas chromatography, mass spectrometry, and alpha, beta, and gamma spectrometry. This dissertation focuses on the application of inverse analysis to gamma spectroscopy to estimate the history of pulse irradiated nuclear material. Previous work in this area has (1) utilized destructive analysis techniques to supplement the nondestructive gamma measurements, and (2) been applied to samples composed of spent nuclear fuel with long irradiation and cooling times. Previous analyses have employed local nonlinear solvers, simple empirical models of gamma spectral features, and simple detector models of gamma spectral features. The algorithm described in this dissertation uses a forward model of the irradiation and measurement process within a global nonlinear optimizer to estimate the unknown irradiation history of pulse irradiated nuclear material. The forward model includes a detector response function for photopeaks only. The algorithm uses a novel hybrid global and local search algorithm to quickly estimate the irradiation parameters, including neutron fluence, cooling time and original composition. Sequential, time correlated series of measurements are used to reduce the uncertainty in the estimated irradiation parameters. This algorithm allows for in situ measurements of interdicted irradiated material. The increase in analysis speed comes with a decrease in information that can be determined, but the sample fluence, cooling time, and composition can be determined within minutes of a measurement. Furthermore, pulse irradiated nuclear material has a characteristic feature that irradiation time and flux cannot be independently estimated. The algorithm has been tested against pulse irradiated samples of pure special nuclear material with cooling times of four minutes to seven hours. The algorithm described is capable of determining the cooling time and fluence the sample was exposed to within 10% as well as roughly estimating the relative concentrations of nuclides present in the original composition.

Consumer acceptance of irradiated food: theory and reality

NASA Astrophysics Data System (ADS)

Bruhn, Christine M.

1998-06-01

For years most consumers have expressed less concern about food irradiation than other food processing technologies. Attitude studies have demonstrated that when given science-based information, from 60% to 90% of consumers prefer the advantages irradiation processing provides. When information is accompanied by samples, acceptance may increase to 99%. Information on irradiation should include product benefits, safety and wholesomeness, address environmental safety issues, and include endorsements by recognized health authorities. Educational and marketing programs should now be directed toward retailers and processors. Given the opportunity, consumers will buy high quality, safety-enhanced irradiated food.

The Effect of UVC Irradiation on the Mechanical Properties of Chitosan Membrane in Sterilization Process

NASA Astrophysics Data System (ADS)

Rupiasih, N. N.; Sumadiyasa, M.; Putra, I. K.

2018-04-01

The present study, we report about the effect of UVC irradiation on the mechanical properties of chitosan membrane in the sterilization process. The membrane used was chitosan membrane 2% which prepared by a casting method using chitosan as matrix and acetic acid 1% as a solvent. The UVC source used was germicidal ultraviolet (UVG) which widely used for sterilization purposes. Variation doses were done by the varying time of irradiation, e.g. 5 min, 15 min, 30 min, and 60 min. Those samples are named as S1, S2, S3, and S4, respectively. Chitosan membrane before irradiation namely S0 also used for comparative study. The effect of UVC irradiation on the mechanical properties of membranes has been examined by different techniques including FTIR, DMA, and the water uptake capability. The results showed that ultimate tensile strength (UTS) and moduli of elasticity (E) were increased by increasing the irradiation time. From FTIR analysis obtained that no new molecules were formed in irradiated membranes. The water uptakes capability of the membranes after irradiation was smaller compared with before irradiation, and among the irradiated membranes, the water uptake capabilities were increased by increasing the exposure time. These observations suggested that more care should be taken during the sterilization process and outdoor used of the membrane. The other side, the UVC irradiation can improve the mechanical properties of the membranes.

Whole-body γ-irradiation decelerates rat hepatocyte polyploidization.

PubMed

Ikhtiar, Adnan M

2015-07-01

To characterize hepatocyte polyploidization induced by intermediate dose of γ-ray. Male Wistar strain rats were whole-body irradiated (WBI) with 2 Gy of γ-ray at the age of 1 month, and 5-6 rats were sacrificed monthly at 0-25 months after irradiation. The nuclear DNA content of individual hepatocytes was measured by flow cytometry, then hepatocytes were classified into various ploidy classes. Survival percentage, after exposure up to the end of the study, did not indicate any differences between the irradiated groups and controls. The degree of polyploidization in hepatocytes of irradiated rats, was significantly lower than that for the control after 1 month of exposure, and it continued to be lower after up to 8 months. Thereafter, the degree of polyploidization in the irradiated group slowly returned to the control level when the irradiated rats reached the age of 10 months. Intermediate dose of ionizing radiation, in contrast to high doses, decelerate hepatocyte polyploidization, which may coincides with the hypothesis of the beneficial effects of low doses of ionizing radiation.

The effect of hold-times on the fatigue behavior of type AISI 316L stainless steel under deuteron irradiation

NASA Astrophysics Data System (ADS)

Scholz, R.; Mueller, R.

1998-10-01

Strain controlled fatigue tests have been performed in torsion at 400°C on type 316L stainless steel samples in both 20% cold worked and annealed conditions during an irradiation with 19 MeV deuterons. A hold-time was imposed in the loading cycle. For the cold worked (cw) material, at shear strain ranges of 1.13% and 1.3%, irradiation creep induced stress relaxation led to the built up of a mean stress. The fatigue life was significantly reduced in comparison to thermal control tests. For the annealed (ann) material, tested under similar experimental conditions, irradiation creep effects were negligibly small compared to cyclic and irradiation hardening. The fatigue life was only slightly reduced. Continuous cycling tests conducted under irradiation conditions lay in the scatter band of the thermal control tests. The difference in fatigue life between continuous cycling and hold-time tests is attributed mainly to the observed difference in irradiation hardening.

Response under low-energy electron irradiation of a thin film of a potential copper precursor for focused electron beam induced deposition (FEBID)

PubMed Central

Sala, Leo; Szymańska, Iwona B; Dablemont, Céline; Lafosse, Anne

2018-01-01

Background: Focused electron beam induced deposition (FEBID) allows for the deposition of free standing material within nanometre sizes. The improvement of the technique needs a combination of new precursors and optimized irradiation strategies to achieve a controlled fragmentation of the precursor for leaving deposited material of desired composition. Here a new class of copper precursors is studied following an approach that probes some surface processes involved in the fragmentation of precursors. We use complexes of copper(II) with amines and perfluorinated carboxylate ligands that are solid and stable under ambient conditions. They are directly deposited on the surface for studying the fragmentation with surface science tools. Results: Infrared spectroscopy and high-resolution electron energy loss spectroscopy (HREELS) are combined to show that the precursor is able to spontaneously lose amine ligands under vacuum. This loss can be enhanced by mild heating. The combination of mass spectrometry and low-energy electron irradiation (0–15 eV) shows that full amine ligands can be released upon irradiation, and that fragmentation of the perfluorinated ligands is induced by electrons of energy as low as 1.5 eV. Finally, the cross section for this process is estimated from the temporal evolution in the experiments on electron-stimulated desorption (ESD). Conclusion: The release of full ligands under high vacuum and by electron irradiation, and the cross section measured here for ligands fragmentation allow one to envisage the use of the two precursors for FEBID studies. PMID:29379701

Design and evaluation of a nondestructive fissile assay device for HTGR fuel samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

McNeany, S. R.; Knoll, R. W.; Jenkins, J. D.

1979-02-01

Nondestructive assay of fissile material plays an important role in nuclear fuel processing facilities. Information for product quality control, plant criticality safety, and nuclear materials accountability can be obtained from assay devices. All of this is necessary for a safe, efficient, and orderly operation of a production plant. Presented here is a design description and an operational evaluation of a device developed to nondestructively assay small samples of High-Temperature Gas-Cooled Reactor (HTGR) fuel. The measurement technique employed consists in thermal-neutron irradiation of a sample followed by pneumatic transfer to a high-efficiency neutron detector where delayed neutrons are counted. In general,more » samples undergo several irradiation and count cycles during a measurement. The total number of delayed-neutron counts accumulated is translated into grams of fissile mass through comparison with the counts accumulated in an identical irradiation and count sequence of calibration standards. Successful operation of the device through many experiments over a one-year period indicates high operational reliability. Tests of assay precision show this to be better than 0.25% for measurements of 10 min. Assay biases may be encountered if calibration standards are not representative of unknown samples, but reasonable care in construction and control of standards should lead to no more than 0.2% bias in the measurements. Nondestructive fissile assay of HTGR fuel samples by thermal-neutron irradiation and delayed-neutron detection has been demonstrated to be a rapid and accurate analysis technique. However, careful attention and control must be given to calibration standards to see that they remain representative of unknown samples.« less

INFLUENCE OF $gamma$-IRRADIATION ON SOME KINDS OF FRUITS AND ON CANNED FRUIT (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khatiashvili, Sh.M.; Tsetskhladze, T.V.; Cherkezishvili, L.I.

1960-01-01

Some results of observations of changes in organoleptic properties of different fresh fruits, their juices, and canned fruit under the influence of gamma irradiation (Co/sup 60/) are given. Irradiation of green persimmons to 1.5 million roentgen at 8500 r/hr leads to the gradual artificial ripening of the fruits. They do not gain any strange taste and are sweeter than the controls. During the same period of time the control green persimmons wither. Figs irradiated with 1.5 million roentgen are well conserved in hermetically closed jars for several weeks without changing their taste. Control flgs go sour in 2 to 3more » days under the same conditions. A wild plum is well conserved under gamma irradiation during a month without any changes of its taste or appearance. The total dose reached 1 miilion rcentgen per month. Control plums wither and rot after two or three days. Peaches irradiated in hermetically closed jars conserve their freshness, consistence, color, and taste for weeks when irradiated with 1.5 million roentgen at 8500 r/hr. With further storage the smell and taste of peaches changes sharply, but the appearance and consistence are conserved without any changes for more than 7 months. The control peaches under the same conditions of storage rot after 4 to 5 days. Tangerines and lemons under irradiation acquire a strange taste beginning at 100 thousand roentgen. If they are irradiated with 750 thousand roentgen, the period of storage is doubled or tripled. The irradiated tangerines have the taste of boiled ones. Grapes under the influence of gamma irradiation begin to spoil at 10000 r. Pink and black cherries are conserved for several weeks without changing their organoleptic properties if the dose is 750,000 r and the dose rate is 8500 r/hr. (auth)« less

Improving the electrical contact at a Pt/TiO2 nanowire interface by selective application of focused femtosecond laser irradiation

NASA Astrophysics Data System (ADS)

Xing, Songling; Lin, Luchan; Zou, Guisheng; Liu, Lei; Peng, Peng; Wu, Aiping; Duley, Walter W.; Zhou, Y. Norman

2017-10-01

In this paper, we show that tightly focused femtosecond laser irradiation is effective in improving nanojoining of an oxide nanowire (NW) (TiO2) to a metal electrode (Pt), and how this process can be used to modify contact states. Enhanced chemical bondings are created due to localized plasmonically enhanced optical absorption at the Pt/TiO2 interface as confirmed by finite element simulations of the localized field distribution during irradiation. Nano Auger electron spectroscopy shows that the resulting heterojunction is depleted in oxygen, suggesting that a TiO2-x layer is formed between the Pt electrode and the TiO2 NW. The presence of this redox layer at the metal/oxide interface plays an important role in decreasing the Schottky barrier height and in facilitating chemical bonding. After laser irradiation at the cathode for 10 s at a fluence of 5.02 mJ cm-2, the Pt/TiO2 NW/Pt structure displays different electrical properties under forward and reverse bias voltage, respectively. The creation of this asymmetric electrical characteristic shows the way in which modification of the electronic interface by laser engineering can replace the electroforming process in resistive switching devices and how it can be used to control contact states in a metal/oxide interface.

Improving the electrical contact at a Pt/TiO2 nanowire interface by selective application of focused femtosecond laser irradiation.

PubMed

Xing, Songling; Lin, Luchan; Zou, Guisheng; Liu, Lei; Peng, Peng; Wu, Aiping; Duley, Walter W; Zhou, Y Norman

2017-10-06

In this paper, we show that tightly focused femtosecond laser irradiation is effective in improving nanojoining of an oxide nanowire (NW) (TiO 2 ) to a metal electrode (Pt), and how this process can be used to modify contact states. Enhanced chemical bondings are created due to localized plasmonically enhanced optical absorption at the Pt/TiO 2 interface as confirmed by finite element simulations of the localized field distribution during irradiation. Nano Auger electron spectroscopy shows that the resulting heterojunction is depleted in oxygen, suggesting that a TiO 2-x layer is formed between the Pt electrode and the TiO 2 NW. The presence of this redox layer at the metal/oxide interface plays an important role in decreasing the Schottky barrier height and in facilitating chemical bonding. After laser irradiation at the cathode for 10 s at a fluence of 5.02 mJ cm -2 , the Pt/TiO 2 NW/Pt structure displays different electrical properties under forward and reverse bias voltage, respectively. The creation of this asymmetric electrical characteristic shows the way in which modification of the electronic interface by laser engineering can replace the electroforming process in resistive switching devices and how it can be used to control contact states in a metal/oxide interface.

Single ion hit detection set-up for the Zagreb ion microprobe

NASA Astrophysics Data System (ADS)

Smith, R. W.; Karlušić, M.; Jakšić, M.

2012-04-01

Irradiation of materials by heavy ions accelerated in MV tandem accelerators may lead to the production of latent ion tracks in many insulators and semiconductors. If irradiation is performed in a high resolution microprobe facility, ion tracks can be ordered by submicrometer positioning precision. However, full control of the ion track positioning can only be achieved by a reliable ion hit detection system that should provide a trigger signal irrespectively of the type and thickness of the material being irradiated. The most useful process that can be utilised for this purpose is emission of secondary electrons from the sample surface that follows the ion impact. The status report of the set-up presented here is based on the use of a channel electron multiplier (CEM) detector mounted on an interchangable sample holder that is inserted into the chamber in a close geometry along with the sample to be irradiated. The set-up has been tested at the Zagreb ion microprobe for different ions and energies, as well as different geometrical arrangements. For energies of heavy ions below 1 MeV/amu, results show that efficient (100%) control of ion impact can be achieved only for ions heavier than silicon. The successful use of the set-up is demonstrated by production of ordered single ion tracks in a polycarbonate film and by monitoring fluence during ion microbeam patterning of Foturan glass.

NREL Solar Radiation Research Laboratory (SRRL): Baseline Measurement System (BMS); Golden, Colorado (Data)

DOE Data Explorer

Stoffel, T.; Andreas, A.

1981-07-15

The SRRL was established at the Solar Energy Research Institute (now NREL) in 1981 to provide continuous measurements of the solar resources, outdoor calibrations of pyranometers and pyrheliometers, and to characterize commercially available instrumentation. The SRRL is an outdoor laboratory located on South Table Mountain, a mesa providing excellent solar access throughout the year, overlooking Denver. Beginning with the basic measurements of global horizontal irradiance, direct normal irradiance and diffuse horizontal irradiance at 5-minute intervals, the SRRL Baseline Measurement System now produces more than 130 data elements at 1-min intervals that are available from the Measurement & Instrumentation Data Center Web site. Data sources include global horizontal, direct normal, diffuse horizontal (from shadowband and tracking disk), global on tilted surfaces, reflected solar irradiance, ultraviolet, infrared (upwelling and downwelling), photometric and spectral radiometers, sky imagery, and surface meteorological conditions (temperature, relative humidity, barometric pressure, precipitation, snow cover, wind speed and direction at multiple levels). Data quality control and assessment include daily instrument maintenance (M-F) with automated data quality control based on real-time examinations of redundant instrumentation and internal consistency checks using NREL's SERI-QC methodology. Operators are notified of equipment problems by automatic e-mail messages generated by the data acquisition and processing system. Radiometers are recalibrated at least annually with reference instruments traceable to the World Radiometric Reference (WRR).

Quality of mixed tropical fruit following irradiation treatment

USDA-ARS?s Scientific Manuscript database

Irradiation can be used to control quarantine insect pests of fresh fruits and vegetables. The economic viability of irradiation improves if a diversity of crops can be treated, but the quality of irradiated produce determines market acceptance. Many tropical fruit tolerate irradiation doses less th...

Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

PubMed

Lemos, J; Neuparth, T; Trigo, M; Costa, P; Vieira, D; Cunha, L; Ponte, F; Costa, P S; Metello, L F; Carvalho, A P

2017-02-01

This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

Relationship of oxygen dose to angiogenesis induction in irradiated tissue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marx, R.E.; Ehler, W.J.; Tayapongsak, P.

1990-11-01

This study was accomplished in an irradiated rabbit model to assess the angiogenic properties of normobaric oxygen and hyperbaric oxygen as compared with air-breathing controls. Results indicated that normobaric oxygen had no angiogenic properties above normal revascularization of irradiated tissue than did air-breathing controls (p = 0.89). Hyperbaric oxygen demonstrated an eight- to ninefold increased vascular density over both normobaric oxygen and air-breathing controls (p = 0.001). Irradiated tissue develops a hypovascular-hypocellular-hypoxic tissue that does not revascularize spontaneously. Results failed to demonstrate an angiogenic effect of normobaric oxygen. It is suggested that oxygen in this sense is a drug requiringmore » hyperbaric pressures to generate therapeutic effects on chronically hypovascular irradiated tissue.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luce, F. P.; Azevedo, G. de M.; Baptista, D. L.

The formation and time resolved behavior of individual Pb nanoparticles embedded in silica have been studied by in-situ transmission electron microscopy observations at high temperatures (400–1100 °C) and under 200 keV electron irradiation. It is shown that under such extreme conditions, nanoparticles can migrate at long distances presenting a Brownian-like behavior and eventually coalesce. The particle migration phenomenon is discussed considering the influence of the thermal energy and the electron irradiation effects on the atomic diffusion process which is shown to control particle migration. These results and comparison with ex-situ experiments tackle the stability and the microstructure evolution of nanoparticles systems undermore » extreme conditions. It elucidates on the effects of energetic particle irradiation-annealing treatments either as a tool or as a detrimental issue that could hamper their long-term applications in radiation-harsh environments such as in space or nuclear sectors.« less

Effect of Panax ginseng saponins and Eleutherococcus senticosus on survival of cultured mammalian cells after ionizing radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ben-Hur, E.; Fulder, S.

Panax ginseng saponin and Eleutherococcus senticosus extract were applied to cells in culture in order to assess the effect of these substances on resistance to gamma-irradiation. Eleutherococcus was slightly radio protective. However, ginseng saponin at a dose of 10 microgram/ml was significantly radioprotective (Do . 2.25 Gy) compared to control (Do . 1.80 Gy) when it was present prior to gamma-irradiation. It enhanced radiation response if it was also present for 4-6 hours after gamma-irradiation (Do . 1.10 Gy). Ginseng-treated cells made 30% less RNA and 14% more protein during a 1 hour pulse of labeled intermediates. The cells weremore » morphologically altered. It is concluded that ginseng saponin can increase radiation resistance. The effect is indirect, due to alterations in cell physiology rather than DNA repair processes.« less

Trapping of hydrogen atoms in X-irradiated salts at room temperature and the decay kinetics

NASA Technical Reports Server (NTRS)

May, C. E.; Philipp, W. H.; Marsik, S. J.

1974-01-01

The salts (hypophosphites, formates, a phosphite, a phosphate, and an oxalate) were X-irradiated, whereby hydrogen formed chemically by a radiolytic process becomes trapped in the solid. By room temperature vacuum extraction, the kinetics for the evolution of this trapped hydrogen was studied mass spectrometrically. All salts except two exhibited second-order kinetics. The two exceptions (NaH2PO2(H2O) and K2HPO4) showed first-order kinetics. Based on experimental results, the escape of hydrogen involves three steps: the diffusion of hydrogen atoms from the bulk to the surface, association of these atoms on the surface (rate controlling step for second-order hydrogen evolution), and the desorption of molecular hydrogen from the surface. The hydrogen does not escape if the irradiated salt is stored in air, apparently because adsorbed air molecules occupy surface sites required in the escape mechanism.

Controlled nanopatterning & modifications of materials by energetic ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinha, O. P.

Compound semiconductors (InP, InAs and GaSb) has been exposed to energetic 3 keV Ar{sup +} ions for a varying fluence range of 10{sup 13} ions/cm{sup 2} to 10{sup 18} ions/cm{sup 2} at room temperature. Morphological modifications of the irradiated surfaces have been investigated by Scanning Tunneling Microscopy (STM) in UHV conditions. It is observed that InP and GaSb have fluence dependent nanopattering e.g. nanoneedle, aligned nanodots, superimposed nanodots ripple like structures while InAs has little fluence dependent behaviour indicating materials dependent growth of features on irradiated surfaces. Moreover, surface roughness and wavelength of the features are also depending on themore » materials and fluences. The RMS surface roughness has been found to be increased rapidly in the early stage of irradiation followed by slower escalate rate and later tends to saturate indicating influence of the nonlinear processes.« less

Comparison of the efficacy of gamma and UV irradiation in sanitization of fresh carrot juice

NASA Astrophysics Data System (ADS)

Jo, Cheorun; Lee, Kyung Haeng

2012-08-01

As there is no pasteurization procedure for the manufacture of fresh vegetable juice, both industry and consumers have sought a method for improving the storage stability and shelf-life of this category of products. In this study, the effects of commercially available, non-thermal pasteurization processes, such as gamma and UV irradiation, were compared for their efficacy in sanitizing fresh carrot juice (FCJ). FCJ was manufactured, packaged, and gamma irradiated with doses of 0, 1, 3, and 5 kGy. The manufactured FCJ was also passed through 4 UV light lamps at doses of 3.67, 4.69, and 6.50 kGy. The total aerobic bacterial count of the FCJ approached the legal limit (105 CFU/mL) after manufacturing. Both treatments were effective in reducing the number of total aerobic bacteria, and the reduced number was maintained during storage for 7 days. Gamma irradiation was more effective in suppressing microbial growth during storage. When the doses for UV treatment and gamma irradiation were higher, the inactivation effects were higher. The reduction of ascorbic acid content was greater upon gamma irradiation than UV treatment. No difference was found in the contents of flavonoids and polyphenols in FCJ after either treatment. After 3 days of refrigerated storage, the sensory scores of gamma- or UV-irradiated FCJ were superior to those of the control. The results indicate that both non-thermal treatments were effective in improving storage stability and extending shelf-life, but gamma irradiation was slightly better in suppressing microbial growth after treatment.

A Review of the Quality and Safety of Irradiated Food.

DTIC Science & Technology

1987-01-01

Construction or Planned.................16 Figure 4: Changes in the Levels of Certain Vitamins in Different Meats Irradiated at High Doses..........24...In the twenty year5 prior to this action, irradiation had been approved for wheat, wheat products, and white potatoes but the process wa- * never used...restriu-t the ujse of . this process or require some type ol labeling. Conumri %>:~ concern about the safety and quality of irradiated food - ha

Decrease in laminin content and protein excretion rate after five sixths nephrectomy and low-dose irradiation in the rat.

PubMed

Aunapuu, Marina; Arend, Andres; Kolts, Ivo; Egerbacher, Monika; Ots, Mai

2004-04-01

The effect of low-dose irradiation on laminin distribution and urine protein excretion in the remnant rat kidney has been studied. The rat remnant kidney formed after 5/6 nephrectomy is an experimental model of chronic renal failure. In the remnant kidney, focal segmental glomerulosclerosis is developed characterized by focal or segmental sclerosis in glomeruli, alterations in the tubules and thickening of the glomerular basement membrane. Low dose irradiation has been presumed to suppress sclerotic processes. In this study 24 male Wistar rats were subdivided into the nephrectomized group, nephrectomized and irradiated groups (1 or 3 Grey), and healthy control group. Animals were sacrificed at 2, 4 and 8 weeks after beginning the experiment. Laminin immunohistochemical staining was found along the tubular and glomerular basement membranes in all experimental groups, but with varying intensity. Laminin content in the basement membranes was decreased in early stages (week 2), especially after irradiation followed by increase during the later stages with relatively high levels at the end of the experiment (week 8). Irradiation at a dose of 3 Grey decreased protein excretion compared to the nephrectomized rats at all stages, while 1 Grey dose was ineffective. Based on decreased proteinuria we conclude that moderate low-dose irradiation has beneficial effects on the rat remnant kidney and that laminin in basement membranes is probably not the most crucial component in regulating membrane permeability.

INFLUENCE OF INTRAMUSCULAR FAT LEVEL ON ORGANOLEPTIC, PHYSICAL, AND CHEMICAL CHARACTERISTICS OF IRRADIATED PORK. I. HIGH-TEMPERATURE SHORT-TIME PRE-IRRADIATION HEAT TREATMENT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bray, R.W.; Weckel, K.G.; Evans, G.W.

1964-02-01

The influence of intramuscular fat (degree of marbling) on characteristics of precooked and irradiated pork muscle was studied. Loins were selected and categorized into three marbling levels by visual appraisal. A relatively high temperature (325 deg F) and short time (2 hr) heat treatment was used for enzyme inactivation. Samples were packed under vacuum in rigid containers and irradiated to 4.5 Mrad with gamma radiation. Irradiated and frozen control samples were evaluated up to 2l0 days later. Degree of marbling had no apparent influence on organoleptic properties of either irradiated or frozen control longissimus dorsi muscle samples. Frozen control samplesmore » were preferred in general appearance, flavor, and over-all acceptability by panelists. Irradiated samples were preferred in texture qualities. Storage time was not a major factor in organoleptic acceptability; however, acceptability of irradiated samples declined between 150 and 210 days of storage. Hunter color attributes were not affected by marbling level. L, a/sub L/ hue, and saturation were increased by radiation treatment. Mechanical tenderness values were decreased due to higher marbling level and radiation treatment. Expressible-moisture values were lowered by radiation treatment and increased with storage time. Iodine numbers were decreased by radiation. Degree of marbling did not affect thiobarbituric acid values but they were significantly lower for irradiated samples. pH values increased with higher levels of intramuscular fat, were significantly higher in irradiated samples than controls, and tended to increase steadily with advancing storage time. (BBB)« less

Effect of combination processing on the microbial, chemical and sensory quality of ready-to-eat (RTE) vegetable pulav

NASA Astrophysics Data System (ADS)

Kumar, R.; George, Johnsy; Rajamanickam, R.; Nataraju, S.; Sabhapathy, S. N.; Bawa, A. S.

2011-12-01

Effect of irradiation in combination with retort processing on the shelf life and safety aspects of an ethnic Indian food product like vegetable pulav was investigated. Gamma irradiation of RTE vegetable pulav was carried out at different dosage rates with 60Co followed by retort processing. The combination processed samples were analysed for microbiological, chemical and sensory characteristics. Microbiological analysis indicated that irradiation in combination with retort processing has significantly reduced the microbial loads whereas the chemical and sensory analysis proved that this combination processing is effective in retaining the properties even after storage for one year at ambient conditions. The results also indicated that a minimum irradiation dosage at 4.0 kGy along with retort processing at an F0 value of 2.0 is needed to achieve the desired shelf life with improved organoleptic qualities.

The pilot plant for electron beam food processing

NASA Astrophysics Data System (ADS)

Migdal, W.; Walis, L.; Chmielewski, A. G.

1993-07-01

In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in INCT. The pilot plant has been constructed inside an old fort what decreases significantly the cost of the investment. The pilot plant is equipped with a small research accelerator Pilot (10 MeV, 1 kW) and an industrial unit Elektronika (10 MeV, 10 kW). This allows both laboratory and full technological scale testing of the elaborated process to be conducted. The industrial unit is being equipped with e-/X conversion target, for high density products irradiation. On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permissions for permanent treatment of spices, garlic, onions and temporary permissions for mushrooms, and potatoes. Dosimetric methods have been elaborated for the routine use at the plant. In the INCT laboratory methods for the control of e-/X treated food have been established.

Spatial and temporal laser pulse design for material processing on ultrafast scales

NASA Astrophysics Data System (ADS)

Stoian, R.; Colombier, J. P.; Mauclair, C.; Cheng, G.; Bhuyan, M. K.; Velpula, P. K.; Srisungsitthisunti, P.

2014-01-01

The spatio-temporal design of ultrafast laser excitation can have a determinant influence on the physical and engineering aspects of laser-matter interactions, with the potential of upgrading laser processing effects. Energy relaxation channels can be synergetically stimulated as the energy delivery rate is synchronized with the material response on ps timescales. Experimental and theoretical loops based on the temporal design of laser irradiation and rapid monitoring of irradiation effects are, therefore, able to predict and determine ideal optimal laser pulse forms for specific ablation objectives. We illustrate this with examples on manipulating the thermodynamic relaxation pathways impacting the ablation products and nanostructuring of bulk and surfaces using longer pulse envelopes. Some of the potential control factors will be pointed out. At the same time the spatial character can dramatically influence the development of laser interaction. We discuss spatial beam engineering examples such as parallel and non-diffractive approaches designed for high-throughput, high-accuracy processing events.

Exercise ameliorates neurocognitive impairments in a translational model of pediatric radiotherapy.

PubMed

Sahnoune, Iman; Inoue, Taeko; Kesler, Shelli R; Rodgers, Shaefali P; Sabek, Omaima M; Pedersen, Steen E; Zawaski, Janice A; Nelson, Katharine H; Ris, M Douglas; Leasure, J Leigh; Gaber, M Waleed

2018-04-09

While cranial radiation therapy (CRT) is an effective treatment, healthy areas surrounding irradiation sites are negatively affected. Frontal lobe functions involving attention, processing speed, and inhibition control are impaired. These deficits appear months to years after CRT and impair quality of life. Exercise has been shown to rejuvenate the brain and aid in recovery post-injury through its effects on neurogenesis and cognition. We developed a juvenile rodent CRT model that reproduces neurocognitive deficits. Next, we utilized the model to test whether exercise ameliorates these deficits. Fischer rats (31 days old) were irradiated with a fractionated dose of 4 Gy × 5 days, trained and tested at 6, 9, and 12 months post-CRT using 5-choice serial reaction time task. After testing, fixed rat brains were imaged using diffusion tensor imaging and immunohistochemistry. CRT caused early and lasting impairments in task acquisition, accuracy, and latency to correct response, as well as causing stunting of growth and changes in brain volume and diffusion. Exercising after irradiation improved acquisition, behavioral control, and processing speed, mitigated the stunting of brain size, and increased brain fiber numbers compared with sedentary CRT values. Further, exercise partially restored global connectome organization, including assortativity and characteristic path length, and while it did not improve the specific regional connections that were lowered by CRT, it appeared to remodel these connections by increasing connectivity between alternate regional pairs. Our data strongly suggest that exercise may be useful in combination with interventions aimed at improving cognitive outcome following pediatric CRT.

Effect of x-ray irradiation on maize inbred line B73 tissue cultures and regenerated plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, A.S.; Cheng, D.S.K.; Milcic, J.B.

In order to enhance variation induced by the tissue culture process and to obtain agronomically desirable mutants, friable embryogenic tissue cultures of maize (Zea mays L.) inbred line B73 were x-ray irradiated with 11 doses (0-8.4 kilorads (kR)). Reductions in callus growth rate and embryogenic callus formation occurred with increasing x-ray doses 20 d and 3 months after irradiation. Callus irradiated with 0.8 kR showed a significant increase in growth rate and a 20% increase in embryogenic callus 9 months after irradiation. A total of 230 R/sub 0/ plants were regenerated for evaluation. Pollen fertility and seed set of R/submore » 0/ plants decreased with increasing x-ray dosage. Days to anthesis and plant height of R/sub 0/ plants varied among x-ray treatments but were generally reduced with higher dosages. The number of chromosomal aberrations increased with x-ray dosage. The R/sub 1/ seeds taken from R/sub 0/ plants were also grown and tested for mutant segregation. Plants regenerated from irradiated calli had a two- to 10-fold increase in mutations over plants regenerated from unirradiated control callus. Germination frequency of seeds from R/sub 0/ plants decreased with increasing x-ray dosage. Although chlorophyll mutants were most frequently observed, a number of vigorous plants with earlier anthesis date were also recovered.« less

Non-contact profilometry of eroded and abraded enamel irradiated with an Er:YAG laser

PubMed Central

Scatolin, Renata Siqueira; Colucci, Vivian; Lepri, Taísa Penazzo; de Alexandria, Adílis Kalina; Maia, Lucianne Cople; Galo, Rodrigo; Borsatto, Maria Cristina; Corona, Silmara Aparecida Milori

2018-01-01

Abstract Literature has reported positive results regarding the use of lasers in the control of erosive lesions; however, evaluating whether they are effective in the control of the progression of erosive/abrasive lesions is important. Objectives This study aimed to evaluate the effect of the Er:YAG laser irradiation in controlling the progression of erosion associated with abrasive lesions in enamel. Material and methods Bovine incisors were sectioned, flattened and polished. Forty-eight enamel slabs were subjected to treatment in an intraoral phase. Twelve volunteers used an intraoral appliance containing one slab that was irradiated with an Er:YAG laser (5.2 J/cm2, 85 mJ, 2 Hz) and another non-irradiated slab on each side of the appliance, during one phase of 5 d, under a split-mouth design. Devices were subjected to erosive challenges (1% citric acid, 5 min, 3 times a day) and abrasive challenges one h after (brushing force of 1.5 N for 15 s) randomly and independently on each side of the device. Measurements of enamel loss were performed via 3D optical profilometry (μm). We analyzed data using the Kruskal-Wallis and Mann-Whitney tests and morphological characteristics via scanning electron microscopy. Results Following erosive and abrasive challenges, the group that was irradiated with the Er:YAG laser presented less loss of structure than the non-irradiated group. The group that underwent erosion and irradiation did not exhibit a significant difference from the non-irradiated group. Conclusion Irradiation with the Er:YAG laser did not control the loss of structure of enamel subjected to erosion but did control abrasion after erosion. PMID:29742259

Non-contact profilometry of eroded and abraded enamel irradiated with an Er:YAG laser.

PubMed

Scatolin, Renata Siqueira; Colucci, Vivian; Lepri, Taísa Penazzo; Alexandria, Adílis Kalina de; Maia, Lucianne Cople; Galo, Rodrigo; Borsatto, Maria Cristina; Corona, Silmara Aparecida Milori

2018-01-01

Literature has reported positive results regarding the use of lasers in the control of erosive lesions; however, evaluating whether they are effective in the control of the progression of erosive/abrasive lesions is important. Objectives This study aimed to evaluate the effect of the Er:YAG laser irradiation in controlling the progression of erosion associated with abrasive lesions in enamel. Material and methods Bovine incisors were sectioned, flattened and polished. Forty-eight enamel slabs were subjected to treatment in an intraoral phase. Twelve volunteers used an intraoral appliance containing one slab that was irradiated with an Er:YAG laser (5.2 J/cm2, 85 mJ, 2 Hz) and another non-irradiated slab on each side of the appliance, during one phase of 5 d, under a split-mouth design. Devices were subjected to erosive challenges (1% citric acid, 5 min, 3 times a day) and abrasive challenges one h after (brushing force of 1.5 N for 15 s) randomly and independently on each side of the device. Measurements of enamel loss were performed via 3D optical profilometry (μm). We analyzed data using the Kruskal-Wallis and Mann-Whitney tests and morphological characteristics via scanning electron microscopy. Results Following erosive and abrasive challenges, the group that was irradiated with the Er:YAG laser presented less loss of structure than the non-irradiated group. The group that underwent erosion and irradiation did not exhibit a significant difference from the non-irradiated group. Conclusion Irradiation with the Er:YAG laser did not control the loss of structure of enamel subjected to erosion but did control abrasion after erosion.

SU-F-P-52: A Meta-Analysis of Controlled Clinical Trials Comparing Elective Nodal Irradiation with Involved-Field Irradiation for Conformal Or Intensity-Modulated Radiotherapy in Patients with Esophageal Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bai, W; Zhang, R; Zhou, Z

Purpose: To compare elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer by a metaanalysis. Methods: Wanfang, CNKI, VIP, CBM databases, PubMed, Embase and Cochrane Library were searched to identify the controlled clinical trials of elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. The obtained data were analyzed using Stata 11.0. The difference between two groups was estimated by calculating the odds ratio (OR) with 95% confidence interval (95% CI). Results: A total of 12 controlled clinical trials involving 1095 esophagealmore » cancer patients, which were selected according to inclusion and exclusion criteria, were included in this meta-analysis. The meta-analysis showed that the elective nodal irradiation group reduced the rates of out-field failure comparing with involved-field irradiation group (OR=3.727, P=0.007). However, the rates of ≥grades 3 acute radiation pneumonitis and esophagitis were significantly higher in the elective nodal irradiation group than in the involved-field irradiation group (OR=0.348, P=0.001, OR=0.385, P=0.000). 1-, 2-, 3-year local control rates (OR=0.966, P=0.837, OR=0.946, P=0.781; OR=0.732P=0.098) and 1-, 3-, 5-year survival rates were similar in the two groups ( OR=0.966, P=0.837; OR=0.946, P=0.781; OR=0.732, P=0.098; OR=0.952, P=0.756; OR=1.149, P=0.422; OR=0.768, P=0.120). It is the same with the rates of distant metastasis (OR=0.986, P=0.937). Conclusion: Compared with involved-field irradiation, the elective nodal irradiation can reduce the rates of out-field failure for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. However, its advantage of local control and survival rates is not obvious and it increases the incidence of toxicities.« less

Treatment of radioactive liquid effluents by reverse osmosis membranes: From lab-scale to pilot-scale.

PubMed

Combernoux, Nicolas; Schrive, Luc; Labed, Véronique; Wyart, Yvan; Carretier, Emilie; Moulin, Philippe

2017-10-15

The recent use of the reverse osmosis (RO) process at the damaged Fukushima-Daiichi nuclear power plant generated a growing interest in the application of this process for decontamination purposes. This study focused on the development of a robust RO process for decontamination of two kinds of liquid effluents: a contaminated groundwater after a nuclear disaster and a contaminated seawater during a nuclear accident. The SW30 HR membrane was selected among other in this study due to higher retentions (96% for Cs and 98% for Sr) in a true groundwater. Significant fouling and scaling phenomenon, attributed to calcium and strontium precipitation, were evidenced in this work: this underscored the importance of the lab scale experiment in the process. Validation of the separation performances on trace radionuclides concentration was performed with similar retention around 96% between surrogates Cs (inactive) and 137 Cs (radioactive). The scale up to a 2.6 m 2 spiral wound membrane led to equivalent retentions (around 96% for Cs and 99% for Sr) but lower flux values: this underlined that the hydrodynamic parameters (flowrate/cross-flow velocity) should be optimized. This methodology was also applied on the reconstituted seawater effluent: retentions were slightly lower than for the groundwater and the same hydrodynamic effects were observed on the pilot scale. Then, ageing of the membrane through irradiation experiments were performed. Results showed that the membrane active layer composition influenced the membrane resistance towards γ irradiation: the SW30 HR membrane performances (retention and permeability) were better than the Osmonics SE at 1 MGy. Finally, to supplement the scale up approach, the irradiation of a spiral wound membrane revealed a limited effect on the permeability and retention. This indicated that irradiation conditions need to be controlled for a further development of the process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Controllable photoinduced optical attenuation in a single-mode optical fiber by irradiation of a femtosecond pulse laser.

PubMed

Himei, Yusuke; Qiu, Jianrong; Nakajima, Sotohiro; Sakamoto, Akihiko; Hirao, Kazuyuki

2004-12-01

Novel optical attenuation fibers were fabricated by the irradiation of a focused infrared femtosecond pulsed laser onto the core of a silica glass single-mode optical fiber. Optical attenuation at a wavelength of 1.55 microm proportionally increased with increasing numbers of irradiation points and was controllable under laser irradiation conditions. The single-mode property of the waveguide and the mode-field diameter of the optical fiber were maintained after irradiation of the femtosecond laser. It is suggested that the attenuation results from optical scattering at photoinduced spots formed inside the fiber core.

Effect of radiation on metabolism of selected minerals in cattle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sasser, L.B.; Wade, L. Jr.; Bell, M.C.

1974-01-01

Zinc, Cu, Ca, Mg, and Fe contents of plasma and/or erythrocytes of steers were studied following exposure of the steers to either whole-body gamma irradiation, BETA irradiation of the gastrointestinal tract, BETA irradiation of the skin, or all combinations of the above. Gastrointestinal (GI) irradiation reduced plasma Zn concentrations 1, 2, and 3 weeks after irradiation, but no detectable change occurred in the erythrocyte concentration of stable Zn. The uptake of /sup 65/Zn by erythrocytes from control steers averaged about 5%; whereas the uptakes of the GI- and skin-irradiated steers exceeded l0%. Hypoferremia and hypercupremia accompanied the injury and infectionmore » produced by GI and skin irradiation. The decline of plasma Ca and Mg levels following GI irradiation appeared to be the result of radiation-induced anorexia, as control animals with a restricted feed intake had a similar reduction in plasma Ca and Mg. (auth)« less

Evaluation of irradiation effects of near-infrared free-electron-laser of silver alloy for dental application.

PubMed

Kuwada-Kusunose, Takao; Kusunose, Alisa; Wakami, Masanobu; Takebayashi, Chikako; Goto, Haruhiko; Aida, Masahiro; Sakai, Takeshi; Nakao, Keisuke; Nogami, Kyoko; Inagaki, Manabu; Hayakawa, Ken; Suzuki, Kunihiro; Sakae, Toshiro

2017-08-01

In the application of lasers in dentistry, there is a delicate balance between the benefits gained from laser treatment and the heat-related damage arising from laser irradiation. Hence, it is necessary to understand the different processes associated with the irradiation of lasers on dental materials. To obtain insight for the development of a safe and general-purpose laser for dentistry, the present study examines the physical effects associated with the irradiation of a near-infrared free-electron laser (FEL) on the surface of a commonly used silver dental alloy. The irradiation experiments using a 2900-nm FEL confirmed the formation of a pit in the dental alloy. The pit was formed with one macro-pulse of FEL irradiation, therefore, suggesting the possibility of efficient material processing with an FEL. Additionally, there was only a slight increase in the silver alloy temperature (less than 0.9 °C) despite the long duration of FEL irradiation, thus inferring that fixed prostheses in the oral cavity can be processed by FEL without thermal damage to the surrounding tissue. These results indicate that dental hard tissues and dental materials in the oral cavity can be safely and efficiently processed by the irradiation of a laser, which has the high repetition rate of a femtosecond laser pulse with a wavelength around 2900 nm.

Effects of irradiated Ergosan on the growth performance and mucus biological components of rainbow trout Oncorhynchus mykiss

NASA Astrophysics Data System (ADS)

Sheikhzadeh, Najmeh; Chehrara, Fatemeh; Heidarieh, Marzieh; Nofouzi, Katayoon; Baradaran, Behzad

2016-01-01

Effects of irradiated and non-irradiated Ergosan extract (alginic acid) on rainbow trout growth performance and skin mucosal immunity were compared. Ergosan was irradiated at 30 kGy in a cobalt-60 irradiator. A total of 252 fish (128.03±9.4 g) were randomly divided into four equal groups, given the basal diet either unsupplemented with Ergosan (control group) or supplemented with crude Ergosan (5 g/kg), ethanol-extracted Ergosan (0.33 g/kg) or irradiated Ergosan (0.33 g/kg) according to this protocol: basal diet for 15 days, treatment diet for 15 days, basal diet for 10 days and treatment diet for 15 days. Highest growth performance was observed in fish fed irradiated Ergosan ( P <0.05). Dietary administration of different Ergosan types did not cause any changes in mucus protein level, but improved alkaline phosphatase level and hemagglutination titer compared with the control (basal diet without Ergosan) on day 55 of feeding trial ( P <0.05). Furthermore, the highest value of lysozyme activity was observed in gamma-irradiated Ergosan on day 55. In conclusion, gamma-irradiated Ergosan at 0.33 g/kg was found to improve growth performance and mucus biological components significantly in comparison with the control group (basal diet without Ergosan).

AGR-1 Irradiation Test Final As-Run Report, Rev. 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collin, Blaise P.

2015-01-01

This document presents the as-run analysis of the AGR-1 irradiation experiment. AGR-1 is the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the US Department of Energy (DOE) as part of the Next-Generation Nuclear Plant (NGNP) project. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel processmore » development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment was irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) for a total duration of 620 effective full power days of irradiation. Irradiation began on December 24, 2006 and ended on November 6, 2009 spanning 13 ATR cycles and approximately three calendar years. The test contained six independently controlled and monitored capsules. Each capsule contained 12 compacts of a single type, or variant, of the AGR coated fuel. No fuel particles failed during the AGR-1 irradiation. Final burnup values on a per compact basis ranged from 11.5 to 19.6 %FIMA, while fast fluence values ranged from 2.21 to 4.39 x 10 25 n/m 2 (E >0.18 MeV). We’ll say something here about temperatures once thermal recalc is done. Thermocouples performed well, failing at a lower rate than expected. At the end of the irradiation, nine of the originally-planned 19 TCs were considered functional. Fission product release-to-birth (R/B) ratios were quite low. In most capsules, R/B values at the end of the irradiation were at or below 10 -7 with only one capsule significantly exceeding this value. A maximum R/B of around 2 x 10 -7 was reached at the end of the irradiation in Capsule 5. Several shakedown issues were encountered and resolved during the first three cycles. These include the repair of minor gas line leaks; repair of faulty gas line valves; the need to position moisture monitors in regions of low radiation fields for proper functioning; the enforcement of proper on-line data storage and backup, the need to monitor thermocouple performance, correcting for detector spectral gain shift, and a change in the mass flow rate range of the neon flow controllers.« less

Resistive switching characteristics of solution-processed Al-Zn-Sn-O films annealed by microwave irradiation

NASA Astrophysics Data System (ADS)

Kim, Tae-Wan; Baek, Il-Jin; Cho, Won-Ju

2018-02-01

In this study, we employed microwave irradiation (MWI) at low temperature in the fabrication of solution-processed AlZnSnO (AZTO) resistive random access memory (ReRAM) devices with a structure of Ti/AZTO/Pt and compared the memory characteristics with the conventional thermal annealing (CTA) process. Typical bipolar resistance switching (BRS) behavior was observed in AZTO ReRAM devices treated with as-deposited (as-dep), CTA and MWI. In the low resistance state, the Ohmic conduction mechanism describes the dominant conduction of these devices. On the other hand, the trap-controlled space charge limited conduction (SCLC) mechanism predominates in the high resistance state. The AZTO ReRAM devices processed with MWI showed larger memory windows, uniform distribution of resistance state and operating voltage, stable DC durability (>103 cycles) and stable retention characteristics (>104 s). In addition, the AZTO ReRAM devices treated with MWI exhibited multistage storage characteristics by modulating the amplitude of the reset bias, and eight distinct resistance levels were obtained with stable retention capability.

Microwave Processing for Sample Preparation to Evaluate Mitochondrial Ultrastructural Damage in Hemorrhagic Shock

NASA Astrophysics Data System (ADS)

Josephsen, Gary D.; Josephsen, Kelly A.; Beilman, Greg J.; Taylor, Jodie H.; Muiler, Kristine E.

2005-12-01

This is a report of the adaptation of microwave processing in the preparation of liver biopsies for transmission electron microscopy (TEM) to examine ultrastructural damage of mitochondria in the setting of metabolic stress. Hemorrhagic shock was induced in pigs via 35% total blood volume bleed and a 90-min period of shock followed by resuscitation. Hepatic biopsies were collected before shock and after resuscitation. Following collection, biopsies were processed for TEM by a rapid method involving microwave irradiation (Giberson, 2001). Samples pre- and postshock of each of two animals were viewed and scored using the mitochondrial ultrastructure scoring system (Crouser et al., 2002), a system used to quantify the severity of ultrastructural damage during shock. Results showed evidence of increased ultrastructural damage in the postshock samples, which scored 4.00 and 3.42, versus their preshock controls, which scored 1.18 and 1.27. The results of this analysis were similar to those obtained in another model of shock (Crouser et al., 2002). However, the amount of time used to process the samples was significantly shortened with methods involving microwave irradiation.

Energy determination in industrial X-ray processing facilities

NASA Astrophysics Data System (ADS)

Cleland, M. R.; Gregoire, O.; Stichelbaut, F.; Gomola, I.; Galloway, R. A.; Schlecht, J.

2005-12-01

In industrial irradiation facilities, the determination of maximum photon or electron energy is important for regulated processes, such as food irradiation, and for assurance of treatment reproducibility. With electron beam irradiators, this has been done by measuring the depth-dose distribution in a homogeneous material. For X-ray irradiators, an analogous method has not yet been recommended. This paper describes a procedure suitable for typical industrial irradiation processes, which is based on common practice in the field of therapeutic X-ray treatment. It utilizes a measurement of the slope of the exponential attenuation curve of X-rays in a thick stack of polyethylene plates. Monte Carlo simulations and experimental tests have been performed to verify the suitability and accuracy of the method between 3 MeV and 8 MeV.

Platelet-Rich Fibrin Lysate Can Ameliorate Dysfunction of Chronically UVA-Irradiated Human Dermal Fibroblasts.

PubMed

Wirohadidjojo, Yohanes Widodo; Budiyanto, Arief; Soebono, Hardyanto

2016-09-01

To determine whether platelet-rich fibrin lysate (PRF-L) could restore the function of chronically ultraviolet-A (UVA)-irradiated human dermal fibroblasts (HDFs), we isolated and sub-cultured HDFs from six different human foreskins. HDFs were divided into two groups: those that received chronic UVA irradiation (total dosages of 10 J cm⁻²) and those that were not irradiated. We compared the proliferation rates, collagen deposition, and migration rates between the groups and between chronically UVA-irradiated HDFs in control and PRF-L-treated media. Our experiment showed that chronic UVA irradiation significantly decreased (p<0.05) the proliferation rates, migration rates, and collagen deposition of HDFs, compared to controls. Compared to control media, chronically UVA-irradiated HDFs in 50% PRF-L had significantly increased proliferation rates, migration rates, and collagen deposition (p<0.05), and the migration rates and collagen deposition of chronically UVA-irradiated HDFs in 50% PRF-L were equal to those of normal fibroblasts. Based on this experiment, we concluded that PRF-L is a good candidate material for treating UVA-induced photoaging of skin, although the best method for its clinical application remains to be determined.

Room-Temperature Activation of InGaZnO Thin-Film Transistors via He+ Irradiation.

PubMed

Stanford, Michael G; Noh, Joo Hyon; Mahady, Kyle; Ievlev, Anton V; Maksymovych, Peter; Ovchinnikova, Olga S; Rack, Philip D

2017-10-11

Amorphous indium gallium zinc oxide (a-IGZO) is a transparent semiconductor which has demonstrated excellent electrical performance as thin-film transistors (TFTs). However, a high-temperature activation process is generally required which is incompatible for next-generation flexible electronic applications. In this work, He + irradiation is demonstrated as an athermal activation process for a-IGZO TFTs. Controlling the He + dose enables the tuning of charge density, and a dose of 1 × 10 14 He + /cm 2 induces a change in charge density of 2.3 × 10 12 cm -2 . Time-dependent transport measurements and time-of-flight secondary ion mass spectroscopy (ToF-SIMS) indicate that the He + -induced trapped charge is introduced because of preferential oxygen-vacancy generation. Scanning microwave impedance microscopy confirms that He + irradiation improves the conductivity of the a-IGZO. For realization of a permanent activation, IGZO was exposed with a He + dose of 5 × 10 14 He + /cm 2 and then aged 24 h to allow decay of the trapped oxide charge originating for electron-hole pair generation. The resultant shift in the charge density is primarily attributed to oxygen vacancies generated by He + sputtering in the near-surface region.

Kinetic Monte Carlo simulations for transient thermal fields: Computational methodology and application to the submicrosecond laser processes in implanted silicon.

PubMed

Fisicaro, G; Pelaz, L; Lopez, P; La Magna, A

2012-09-01

Pulsed laser irradiation of damaged solids promotes ultrafast nonequilibrium kinetics, on the submicrosecond scale, leading to microscopic modifications of the material state. Reliable theoretical predictions of this evolution can be achieved only by simulating particle interactions in the presence of large and transient gradients of the thermal field. We propose a kinetic Monte Carlo (KMC) method for the simulation of damaged systems in the extremely far-from-equilibrium conditions caused by the laser irradiation. The reference systems are nonideal crystals containing point defect excesses, an order of magnitude larger than the equilibrium density, due to a preirradiation ion implantation process. The thermal and, eventual, melting problem is solved within the phase-field methodology, and the numerical solutions for the space- and time-dependent thermal field were then dynamically coupled to the KMC code. The formalism, implementation, and related tests of our computational code are discussed in detail. As an application example we analyze the evolution of the defect system caused by P ion implantation in Si under nanosecond pulsed irradiation. The simulation results suggest a significant annihilation of the implantation damage which can be well controlled by the laser fluence.

Communication: Light driven remote control of microgels' size in the presence of photosensitive surfactant: Complete phase diagram

NASA Astrophysics Data System (ADS)

Schimka, Selina; Gordievskaya, Yulia D.; Lomadze, Nino; Lehmann, Maren; von Klitzing, Regine; Rumyantsev, Artem M.; Kramarenko, Elena Yu.; Santer, Svetlana

2017-07-01

Here we report on a light triggered remote control of microgel size in the presence of photosensitive surfactant. The hydrophobic tail of the cationic surfactant contains azobenzene group that undergoes a reversible photo-isomerization reaction from a trans- to a cis-state accompanied by a change in the hydrophobicity of the surfactant. We have investigated light assisted behaviour and the complex formation of the microgels with azobenzene containing surfactant over the broad concentrational range starting far below and exceeding several times of the critical micelle concentration (CMC). At small surfactant concentration in solution (far below CMC), the surfactant in the trans-state accommodates within the microgel causing its compaction, while the cis-isomer desorbs out of microgel resulting in its swelling. The process of the microgel size change can be described as swelling on UV irradiation (trans-cis isomerization) and shrinking on irradiation with blue light (cis-trans isomerization). However, at the surfactant concentrations larger than CMC, the opposite behaviour is observed: the microgel swells on blue irradiation and shrinks during exposure to UV light. We explain this behaviour theoretically taking into account isomer dependent micellization of surfactant within the microgels.

Effects of phototherapy on cartilage structure and inflammatory markers in an experimental model of osteoarthritis

NASA Astrophysics Data System (ADS)

Oliveira, Poliani; Santos, Anderson Amaro; Rodrigues, Tamara; Tim, Carla Roberta; Pinto, Karina Zambone; Magri, Angela Maria Paiva; Fernandes, Kelly Rossetti; Mattiello, Stela M.; Parizotto, Nivaldo Antonio; Anibal, Fernanda Freitas; Rennó, Ana Claudia Muniz

2013-12-01

The aim of this study was to evaluate the effects of laser phototherapy on the degenerative modifications on the articular cartilage after the anterior cruciate ligament transection (ACLT) in the knee of rats. Eighty male rats (Wistar) were distributed into four groups: intact control group (IG), injured control group (CG), injured laser treated group at 10 J/cm2 (L10), and injured laser treated group at 50 J/cm2 (L50). Animals were distributed into two subgroups, sacrificed in 5 and 8 weeks postsurgery. The ACLT was used to induce knee osteoarthritis in rats. After 2 weeks postsurgery, laser phototherapy initiated and it was performed for 15 and 30 sessions. The histological findings revealed that laser irradiation, especially at 10 J/cm2, modulated the progression of the degenerative process, showing a better cartilage structure and lower number of condrocytes compared to the other groups. Laser phototherapy was not able to decrease the degenerative process measured by Mankin score and prevent the increase of cartilage thickness related to the degenerative process. Moreover, it did not have any effect in the biomodulation of the expression of markers IL1β, tumor necrosis factor-α, and metalloprotein-13. Furthermore, laser irradiated animals, at 50 J/cm2 showed a lower amount of collagen type 1.

Controllable generation of reactive oxygen species by femtosecond-laser irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Wei; He, Hao, E-mail: haohe@tju.edu.cn; Wang, Yintao

Femtosecond lasers have been advancing Biophotonics research in the past two decades with multiphoton microscopy, microsurgery, and photodynamic therapy. Nevertheless, laser irradiation is identified to bring photodamage to cells via reactive oxygen species (ROS) generation with unclear mechanism. Meanwhile, currently in biological researches, there is no effective method to provide controllable ROS production precisely, which originally is leaked from mitochondria during respiration and plays a key role in a lot of important cellular processes and cellular signaling pathways. In this study, we show the process of how the tightly focused femtosecond-laser induces ROS generation solely in mitochondria at the verymore » beginning and then release to cytosol if the stimulus is intense enough. At certain weak power levels, the laser pulses induce merely moderate Ca{sup 2+} release but this is necessary for the laser to generate ROS in mitochondria. Cellular original ROS are also involved with a small contribution. When the power is above a threshold, ROS are then released to cytosol, indicating photodamage overwhelming cellular repair ability. The mechanisms in those two cases are quite different. Those results clarify parts of the mechanism in laser-induced ROS generation. Hence, it is possible to further this optical scheme to provide controllable ROS generation for ROS-related biological researches including mitochondrial diseases and aging.« less

Effect of gamma irradiation on the antimicrobial and free radical scavenging activities of Glycyrrhiza glabra root

NASA Astrophysics Data System (ADS)

Fatima Khattak, Khanzadi; James Simpson, Thomas

2010-04-01

The efficacy of gamma irradiation as a method of decontamination for food and herbal materials is well established. In the present study, Glycyrrhiza glabra roots were irradiated at doses 5, 10, 15, 20 and 25 kGy in a cobalt-60 irradiator. The irradiated and un-irradiated control samples were evaluated for phenolic contents, antimicrobial activities and DPPH scavenging properties. The result of the present study showed that radiation treatment up to 20 kGy does not affect the antifungal and antibacterial activity of the plant. While sample irradiated at 25 kGy does showed changes in the antibacterial activity against some selected pathogens. No significant differences in the phenolic contents were observed for control and samples irradiated at 5, 10 and 15 kGy radiation doses. However, phenolic contents increased in samples treated with 20 and 25 kGy doses. The DPPH scavenging activity significantly ( p<0.05) increased in all irradiated samples of the plant.

PROCESS FOR DECONTAMINATING THORIUM AND URANIUM WITH RESPECT TO RUTHENIUM

DOEpatents

Meservey, A.A.; Rainey, R.H.

1959-10-20

The control of ruthenium extraction in solvent-extraction processing of neutron-irradiated thorium is presented. Ruthenium is rendered organic-insoluble by the provision of sulfite or bisulfite ions in the aqueous feed solution. As a result the ruthenium remains in the aqueous phase along with other fission product and protactinium values, thorium and uranium values being extracted into the organic phase. This process is particularly applicable to the use of a nitrate-ion-deficient aqueous feed solution and to the use of tributyl phosphate as the organic extractant.

Light induced kickoff of magnetic domain walls in Ising chains

NASA Astrophysics Data System (ADS)

Bogani, Lapo

2012-02-01

Controlling the speed at which systems evolve is a challenge shared by all disciplines, and otherwise unrelated areas use common theoretical frameworks towards this goal. A particularly widespread model is Glauber dynamics, which describes the time evolution of the Ising model and can be applied to any binary system. Here we show, using molecular nanowires under irradiation, that Glauber dynamics can be controlled by a novel domain-wall kickoff mechanism. Contrary to known processes, the kickoff has unambiguous fingerprints, slowing down the spin-flip attempt rate by several orders of magnitude, and following a scaling law. The required irradiation power is very low, a substantial improvement over present methods of magnetooptical switching: in our experimental demonstration we switched molecular nanowires with light, using powers thousands of times lower than in previous optical switching methods. This manipulation of stochastic dynamic processes is extremely clean, leading to fingerprint signatures and scaling laws. These observations can be used, in material science, to better study domain-wall displacements and solitons in discrete lattices. These results provide a new way to control and study stochastic dynamic processes. Being general for Glauber dynamics, they can be extended to different kinds of magnetic nanowires and to a myriad of fields, ranging from social evolution to neural networks and chemical reactivity. For nanoelectronics and molecular spintronics the kickoff affords external control of molecular spin-valves and a magnetic fingerprint in single molecule measurements. It can also be applied to the dynamics of mechanical switches and the related study of phasons and order-disorder transitions.

A coherent light scanner for optical processing of large format transparencies

NASA Technical Reports Server (NTRS)

Callen, W. R.; Weaver, J. E.; Shackelford, R. G.; Walsh, J. R.

1975-01-01

A laser scanner is discussed in which the scanning beam is random-access addressable and perpendicular to the image input plane and the irradiance of the scanned beam is controlled so that a constant average irradiance is maintained after passage through the image plane. The scanner's optical system and design are described, and its performance is evaluated. It is noted that with this scanner, data in the form of large-format transparencies can be processed without the expense, space, maintenance, and precautions attendant to the operation of a high-power laser with large-aperture collimating optics. It is shown that the scanned format as well as the diameter of the scanning beam may be increased by simple design modifications and that higher scan rates can be achieved at the expense of resolution by employing acousto-optic deflectors with different relay optics.

Photomorphogenesis in Sinningia speciosa, cv. Queen Victoria II. Stem Elongation: Interaction of a Phytochrome Controlled Process and a Red-requiring, Energy Dependent Reaction.

PubMed

Satter, R L; Wetherell, D F

1968-06-01

When Sinningia plants were grown with fluorescent light of photosynthetic intensity for 8 hours each day, stems became abnormally elongated when the P(FR) level was lowered by far red light given during the last half of several consecutive nights. However, plants were even taller if the source also emitted red light. Elongation was independent of the red/far red energy ratio if it was lower than one, but dependent upon irradiance at all values tested.Elongation of plants irradiated by a well filtered far red source was presumed to be limited by a shortage of respiratory substrate. Enhancement by radiation shorter than 700 mmu was attributed to promotion of processes leading to increased substrate supply. Protochlorophyllide was regarded as the primary photoreceptor. Its photoreduction promoted chlorophyll synthesis which, in turn, increased photosynthetic capacity and thus substrate supply.

Total Ionizing Dose Effects on Strained Ge pMOS FinFETs on Bulk Si

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, En Xia; Fleetwood, Daniel M.; Hachtel, Jordan A.

2016-12-02

In this paper, we have characterized the total ionizing dose response of strained Ge p MOS FinFETs built on bulk Si using a fin replacement process. Devices irradiated to 1.0 Mrad(SiO 2) show minimal transconductance degradation (less than 5%), very small V th shifts (less than 40 mV in magnitude) and very little ON/OFF current ratio degradation (<5%), and only modest variation in radiation response with transistor geometry (typically less than normal part-to-part variation). Both before and after irradiation, the performance of these strained Ge p MOS FinFETs is far superior to that of past generations of planar Ge pmore » MOS devices. Finally, these improved properties result from significant improvements in processing technology, as well as the enhanced gate control provided by the strained Ge FinFET technology.« less

A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber

NASA Astrophysics Data System (ADS)

Chiang, W. Y.; Wu, M. H.; Wu, K. L.; Lin, M. H.; Teng, H. H.; Tsai, Y. F.; Ko, C. C.; Yang, E. C.; Jiang, J. A.; Barnett, L. R.; Chu, K. R.

2014-08-01

Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.

Photomorphogenesis in Sinningia speciosa, cv. Queen Victoria I. Characterization of Phytochrome Control.

PubMed

Satter, R L; Wetherell, D F

1968-06-01

The morphological development of Sinningia speciosa plants that were exposed to supplementary far red light was very different from that of plants receiving dark nights. After several nights of such irradiation, stems and petioles were elongated, petioles were angulated, leaf blade expansion was inhibited, plants were chlorotic and the accumulation of shoot dry weight was retarded.Red reversibility of the morphological changes potentiated by far red light indicated control by the phytochrome system. A high P(FR) level during the last half of the night inhibited stem elongation and promoted leaf blade expansion, but both of these processes were hardly affected by the P(FR) level during the first half of the night. Thus sensitivity to P(FR) was cyclic.The interpretation of our experiments was complicated by quantitative morphological differences resulting from long, as compared to short, far red irradiations.

A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber.

PubMed

Chiang, W Y; Wu, M H; Wu, K L; Lin, M H; Teng, H H; Tsai, Y F; Ko, C C; Yang, E C; Jiang, J A; Barnett, L R; Chu, K R

2014-08-01

Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.

CAPABILITY TO RECOVER PLUTONIUM-238 IN H-CANYON/HB-LINE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuller, Kenneth S. Jr.; Smith, Robert H. Jr.; Goergen, Charles R.

2013-01-09

Plutonium-238 is used in Radioisotope Thermoelectric Generators (RTGs) to generate electrical power and in Radioisotope Heater Units (RHUs) to produce heat for electronics and environmental control for deep space missions. The domestic supply of Pu-238 consists of scrap material from previous mission production or material purchased from Russia. Currently, the United States has no significant production scale operational capability to produce and separate new Pu-238 from irradiated neptunium-237 targets. The Department of Energy - Nuclear Energy is currently evaluating and developing plans to reconstitute the United States capability to produce Pu-238 from irradiated Np-237 targets. The Savannah River Site hadmore » previously produced and/or processed all the Pu-238 utilized in Radioisotope Thermoelectric Generators (RTGs) for deep space missions up to and including the majority of the plutonium for the Cassini Mission. The previous full production cycle capabilities included: Np-237 target fabrication, target irradiation, target dissolution and Np-237 and Pu-238 separation and purification, conversion of Np-237 and Pu-238 to oxide, scrap recovery, and Pu-238 encapsulation. The capability and equipment still exist and could be revitalized or put back into service to recover and purify Pu-238/Np-237 or broken General Purpose Heat Source (GPHS) pellets utilizing existing process equipment in HB-Line Scrap Recovery, and H-anyon Frame Waste Recovery processes. The conversion of Np-237 and Pu-238 to oxide can be performed in the existing HB-Line Phase-2 and Phase-3 Processes. Dissolution of irradiated Np-237 target material, and separation and purification of Np-237 and Pu-238 product streams would be possible at production rates of ~ 2 kg/month of Pu-238 if the existing H-Canyon Frames Process spare equipment were re-installed. Previously, the primary H-Canyon Frames equipment was removed to be replaced: however, the replacement project was stopped. The spare equipment is stored and still available for installation. Out of specification Pu-238 scrap material can be purified and recovered by utilizing the HB-Line Phase-1 Scrap Recovery Line and the Phase-3 Pu-238 Oxide Conversion Line along with H-Canyon Frame Waste Recovery process. In addition, it also covers and describes utilizing the Phase-2 Np-237 Oxide Conversion Line, in conjunction with the H-Canyon Frames Process to restore the H-Canyon capability to process and recover Np-237 and Pu-238 from irradiated Np-237 targets and address potential synergies with other programs like recovery of Pu-244 and heavy isotopes of curium from other target material.« less

Transfusion of irradiated red blood cell units with a potassium adsorption filter: A randomized controlled trial.

PubMed

Cid, Joan; Villegas, Vanessa; Carbassé, Gloria; Alba, Cristina; Perea, Dolores; Lozano, Miguel

2016-05-01

The irradiation of red blood cells (RBCs) causes damage of the RBC membrane with increased potassium (K) leak during storage compared with nonirradiated RBC units of similar age. A previous in vitro study showed a mean reduction of K of 94 ± 5% with a potassium adsorption filter (PAF). A prospective, single-center, nonblinded, randomized controlled trial (RCT) was designed to evaluate the safety and efficacy of transfusing irradiated RBC units with the PAF. Patients 18 years of age or older who received irradiated RBC units due to chemotherapy-induced anemia were randomly assigned to receive irradiated RBC units with the PAF (PAF group) or with the standard blood infusion set (control group). Primary outcome measures were safety and efficacy of the PAF (absolute change in hemoglobin [Hb] and K, respectively, in patient's blood values after transfusing the irradiated RBC units with or without the PAF). A total of 63 irradiated RBC units were transfused to 17 patients in the control group, and a total of 56 irradiated RBC units were transfused to 13 patients in the PAF group. The absolute change of Hb (9.3 ± 6.3 g/L vs. 8.1 ± 5.8 g/L; p = 0.3) and the absolute change of K (-0.01 ± 0.4 mmol/L vs. -0.01 ± 0.3 mmol/L; p = 0.2) were comparable between the two groups of the trial. The transfusion of 1 irradiated RBC unit with the PAF was as safe and efficacious as the transfusion of 1 irradiated RBC unit with the standard blood infusion set in patients with chemotherapy-induced anemia. © 2016 AABB.

Industrial uses of radiation processing in Belgium

NASA Astrophysics Data System (ADS)

Lacroix, J. P.

Since 1979, the Irradiation Department of IRE, in conjunction with universities and the industrial sector, has set up an extensive programme of research, development and promotion of the radiation process applied to cross-linking and polymerization of plastics, to waste treatment and to food preservation. Starting from scratch, it is thanks to our research in this last-mentioned field that we have been able to develop and to increase the application of the irradiation process within the food industry. At present, two irradiation facilities of a total design capacity of 2.5 10 6 Ci irradiate 24 hours per day mostly for the agro-industry.

Verification on the Dose Profile Variation of a 3-D—NIPAM Polymer Gel Dosimeter

NASA Astrophysics Data System (ADS)

Hsieh, Bor-Tsung; Wu, Jay; Chang, Yuan-Jen

2013-04-01

A gel dosimeter is a three-dimensional (3-D) device that is used in radiotherapy. It is more efficient than traditional one-dimensional and two-dimensional dosimeters because it can be used in complicated radiation therapy applications. However, the achievement of temporal and spatial stabilities for gel dosimeters remains challenging in clinical applications because the fabrication process affects the polymerization reaction during irradiation. This study investigated the dose profile variation of an N-isopropyl acrylamide (NIPAM) polymer gel dosimeter by using the 3-D optical computed tomography scanner OCTOPUSTM 10X (MGS Research Inc.). Two acrylic containers (diameter=10, height=10, and diameter=15, height=15cm ) filled with polymer gel (gelatin: 5%, NIPAM: 5%, Bis: 3%, THPC: 5 mM) were irradiated by using intensity-modulated radiotherapy (SIEMENS Oncor Impression, 6 MV Photo beam). The treatment field was a 3 cm 3 cm square field, and the prescribed dose was 5 Gy. The results of the reconstruction line profile showed that the uncertainty of non-irradiated gel is less than 1.3% when a container with 10 cm diameters cooled in a refrigerator with a water bath. The maximum uncertainties of the irradiated gel at 24 h, 48 h, and 72 h post-irradiation were 2.9%, 2.9%, and 3.1%, respectively. However, the maximum uncertainty of the non-irradiated gel dosimeter increased to 3% when a container with 15 cm diameter was cooled in the same refrigerator. After irradiation, the maximum uncertainties of the irradiated gel at 24 h, 48 h, and 72 h post-irradiation were 13.1%, 13.7%, and 12.95%, respectively. The uncertainty differences for gels at different container sizes were attributed to the different cooling rates that were applied to the gels. The time required for large gel containers to cool in the refrigerator was more than 10 h, whereas the cooling process only took 4.2 h for gels in a small container. The time difference produced different temperature histories for gels and may result in changes in gel sensitivity. Given the thermally induced pre-radiation polymerization, the time difference resulted in a deviation in dose profiles. This study reports that thermal control during gel preparation should be carefully performed for clinical applications to achieve a more accurate dose distribution in 3-D image reconstruction.

Proteomic Analysis Implicates Dominant Alterations of RNA Metabolism and the Proteasome Pathway in the Cellular Response to Carbon-Ion Irradiation

PubMed Central

Xie, Da-Fei; Xie, Yi; Liu, Xiao-Dan; Wang, Qi; Sui, Li; Song, Man; Zhang, Hong; Zhou, Jianhua; Zhou, Ping-Kun

2016-01-01

Radiotherapy with heavy ions is considered advantageous compared to irradiation with photons due to the characteristics of the Braggs peak and the high linear energy transfer (LET) value. To understand the mechanisms of cellular responses to different LET values and dosages of heavy ion radiation, we analyzed the proteomic profiles of mouse embryo fibroblast MEF cells exposed to two doses from different LET values of heavy ion 12C. Total proteins were extracted from these cells and examined by Q Exactive with Liquid Chromatography (LC)—Electrospray Ionization (ESI) Tandem MS (MS/MS). Using bioinformatics approaches, differentially expressed proteins with 1.5 or 2.0-fold changes between different dosages of exposure were compared. With the higher the dosage and/or LET of ion irradiation, the worse response the cells were in terms of protein expression. For instance, compared to the control (0 Gy), 771 (20.2%) proteins in cells irradiated at 0.2 Gy of carbon-ion radiation with 12.6 keV/μm, 313 proteins (8.2%) in cells irradiated at 2 Gy of carbon-ion radiation with 12.6 keV/μm, and 243 proteins (6.4%) in cells irradiated at 2 Gy of carbon-ion radiation with 31.5 keV/μm exhibited changes of 1.5-fold or greater. Gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Munich Information Center for Protein Sequences (MIPS) analysis, and BioCarta analysis all indicated that RNA metabolic processes (RNA splicing, destabilization and deadenylation) and proteasome pathways may play key roles in the cellular response to heavy-ion irradiation. Proteasome pathways ranked highest among all biological processes associated with heavy carbon-ion irradiation. In addition, network analysis revealed that cellular pathways involving proteins such as Col1a1 and Fn1 continued to respond to high dosages of heavy-ion irradiation, suggesting that these pathways still protect cells against damage. However, pathways such as those involving Ikbkg1 responded better at lower dosages than at higher dosages, implying that cell damage would occur when the networks involving these proteins stop responding. Our investigation provides valuable proteomic information for elucidating the mechanism of biological effects induced by carbon ions in general. PMID:27711237

Effects of gamma radiation on raspberries: safety and quality issues.

PubMed

Verde, S Cabo; Trigo, M J; Sousa, M B; Ferreira, A; Ramos, A C; Nunes, I; Junqueira, C; Melo, R; Santos, P M P; Botelho, M L

2013-01-01

There is an ever-increasing global demand from consumers for high-quality foods with major emphasis placed on quality and safety attributes. One of the main demands that consumers display is for minimally processed, high-nutrition/low-energy natural foods with no or minimal chemical preservatives. The nutritional value of raspberry fruit is widely recognized. In particular, red raspberries are known to demonstrate a strong antioxidant capacity that might prove beneficial to human health by preventing free radical-induced oxidative stress. However, food products that are consumed raw, are increasingly being recognized as important vehicles for transmission of human pathogens. Food irradiation is one of the few technologies that address both food quality and safety by virtue of its ability to control spoilage and foodborne pathogenic microorganisms without significantly affecting sensory or other organoleptic attributes of the food. Food irradiation is well established as a physical, nonthermal treatment (cold pasteurization) that processes foods at or nearly at ambient temperature in the final packaging, reducing the possibility of cross contamination until the food is actually used by the consumer. The aim of this study was to evaluate effects of gamma radiation on raspberries in order to assess consequences of irradiation. Freshly packed raspberries (Rubus idaeus L.) were irradiated in a (60)Co source at several doses (0.5, 1, or 1.5 kGy). Bioburden, total phenolic content, antioxidant activity, physicochemical properties such as texture, color, pH, soluble solids content, and acidity, and sensorial parameters were assessed before and after irradiation and during storage time up to 14 d at 4°C. Characterization of raspberries microbiota showed an average bioburden value of 10(4) colony-forming units (CFU)/g and a diverse microbial population predominantly composed of two morphological types (gram-negative, oxidase-negative rods, 35%, and filamentous fungi, 41%). The inactivation studies on the raspberries mesophilic population indicated a one log reduction of microbial load (95% inactivation efficiency for 1.5 kGy), in the surviving population mainly constituted by filamentous fungi (79-98%). The total phenolic content of raspberries indicated an increase with radiation doses and a decrease with storage time. The same trend was found for raspberries' antioxidant capacity with storage time. Regarding raspberries physicochemical properties, irradiation induced a significant decrease in firmness compared with nonirradiated fruit. However, nonirradiated and irradiated fruit presented similar physicochemical and sensory properties during storage time. Further studies are needed to elucidate the benefits of irradiation as a raspberries treatment process.

Methods for routine control of irradiated food: Determination of the irradiation status of shellfish by thermoluminescence analysis

NASA Astrophysics Data System (ADS)

Schreiber, G. A.; Hoffmann, A.; Helle, N.; Bögl, K. W.

1994-06-01

In some countries, clearance has been given for treating certain types of shellfish by ionizing radiation in order to increase the shelf-life and to reduce health hazards which might be caused by contaminating microorganisms. In the present study, thermoluminescence (TL) analysis was used to examine the irradiation status of shellfish products purchased from local suppliers. For analysis minerals were isolated from the guts of the animals. Although on none of the examined products an irradiation treatment prior to analysis could be shown, the results obtained on non-irradiated and irradiated products have revealed that irradiation within the commercially used dose range can clearly be detected. Already first glow TL intensities of minerald indicated irradiation treatments. Normalized TL signals of non-irradiated and irradiated samples were clearly separated. By calculation of differences of TL intensities and TL signals between non-irradiated and irradiated samples in dependency of integration temperature an optimized integration area for glow curves was determined. The result of this study agree well with results obtained by two large-scale intercomparisons between food control laboratories to detect irradiation treatment of spices and herbal products as well as of fruit and vegetables by TL analysis of contaminating minerals.

Effects of X-ray irradiation on different stages of Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae) and DNA damage

NASA Astrophysics Data System (ADS)

Avan Aksoy, Hatice; Yazıcı, Nizamettin; Erel, Yakup

2017-01-01

The corn stalk borer, Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae) is an important corn pest in the Mediterranean countries. In this study, we investigated the influence of X-ray irradiation on different developmental stages, reproduction and DNA damage to the insect. Eggs (0-24 h old), larvae (5th instar), pupae (5 days after pupation) and adults (24 h after emergence) were irradiated with X-ray irradiation at target doses of 0 (control), 50, 100, 150 and 200 Gy. Eggs irradiated at all doses did not hatch. When 5th instar were irradiated pupation and adult emergence significantly decreased. Fecundity of adults from irradiated pupae was inhibited and no eggs were laid. Moreover, adult longevity decreased after irradiation compared to control. Larvae, pupae, and adults of S. nonagrioides were studied using the single-cell gel electrophoresis (DNA comet) directly after irradiation. X-ray irradiated larvae, pupae, and adults showed typical DNA fragmentation in a dose-dependent manner compared with cells from non-irradiated groups. The amount of DNA damage increased as doses increased and possibly could be used to estimate dose applied in commercial phytosanitary irradiation treatments. Furthermore, irradiation would be an effective phytosanitary treatment for shipped commodities at risk infestation with S. nonagrioides.

Effect of Ultrasonic Frequency on Lactic Acid Fermentation Promotion by Ultrasonic Irradiation

NASA Astrophysics Data System (ADS)

Shimada, Tadayuki; Ohdaira, Etsuzo; Masuzawa, Nobuyoshi

2004-05-01

The authors have been researching the promotion of lactic acid fermentation by ultrasonic irradiation. In the past research, it was proven that ultrasonic irradiation is effective in the process of fermentation, and the production of yoghurt and kefir was promoted. In this study, the effect of the ultrasonic frequency in this fermentation process was examined. In the frequency range of this study, it was found that the action of fermentation promotion was exponentially proportionate to the irradiated ultrasonic frequency.

[Study on chemical compositions and crystallinity changes of bamboo treated with gamma rays].

PubMed

Sun, Feng-Bo; Jiang, Ze-hui; Fei, Ben-hua; Lu, Fang; Yu, Zi-xuan; Chang, Xiang-zhen

2011-07-01

The structures and qualities of main chemical compositions in cell wall of bamboo treated with gamma rays were tested by nuclear magnetic resonance spectrometer (NMR) and X-ray Diffraction (XRD). The result indicated that the bamboo crystallinity increased at the beginning of irradiation process, while the crystallinity reduced when the irradiation dose was raised to about 100 kGy. During the whole irradiation process, hemicellulose degraded, and with the irradiation doses increased the non-phenolic lignin changed to the phenolic.

[Study on bamboo treated with gamma rays by X-ray diffraction].

PubMed

Sun, Feng-Bo; Fei, Ben-Hua; Jiang, Ze-Hui; Yu, Zi-Xuan; Tian, Gen-Lin; Yang, Quan-Wen

2011-06-01

The microfibril angle and crystallinity of bamboo treated with gamma rays were tested by X-ray diffraction (XRD). The result indicated that crystallinity in bamboo increased when irradiation dose was less than 100 kGy, while the irradiation dose was raised to about 100 kGy, crystallinity in bamboo reduced. But during the whole irradiation process, the influence on microfibril angle was not obvious, so it was not the dominant factors on variation in physical-mechanical properties of bamboo during the process of irradiation.

Aquatic Plant Control Research Program: Effects of Salinity and Irradiance Conditions on the Growth, Morphology and Chemical Composition of Submersed Aquatic Macrophytes

DTIC Science & Technology

1990-07-01

L , AQUATIC PLANT CONTROL RESEARCH PROGRAM * * TECHNICAL REPORT A-90-5 EFFECTS OF SALINITY AND IRRADIANCE CONDITIONS ON THE GROWTH, MORPHOLOGY AND...UNIT ELEMENT NO. NO. NO. ACCESSION NO. 11. TITLE (Indude Security Classification) Effects of Salinity and Irradiance Conditions on the Growth...Dr. Robert W. Whalin. This report should be cited as follows: Twilley, Robert R., and Barko, John W. 1990. " Effects of Salinity and Irradiance

Cost effective alternative to low irradiance measurements

NASA Technical Reports Server (NTRS)

Oleary, Scott T.

1988-01-01

Martin Marietta's Space Simulation Laboratory (SSL) has a Thermal Environment Simulator (TES) with 56 individually controlled heater zones. The TES has a temperature range of approximately minus 129 C to plus 149 C. Because of the ability of TES to provide complex irradiance distributions, it is necessary to be able to measure a wide range of irradiance levels. SSL currently uses ambient temperature controlled radiometers with the capacity to measure sink irradiance levels of approximately 42.6 mw/sq cm, sink temperature equals 21 C and up. These radiometers could not be used to accurately measure the lower irradiance levels of the TES. Therefore, it was necessary to obtain a radiometer or develop techniques which could be used to measure lower irradiance levels.

Generation of novel covalent RNA-protein complexes in cells by ultraviolet B irradiation: implications for autoimmunity.

PubMed

Andrade, Felipe; Casciola-Rosen, Livia A; Rosen, Antony

2005-04-01

To determine whether ultraviolet B (UVB) irradiation induces novel modifications in autoantigens targeted during experimental photoinduced epidermal damage. To search for novel UVB-induced autoantigen modifications, lysates made from UVB-irradiated human keratinocytes or HeLa cells were immunoblotted using human autoantibodies that recognize ribonucleoprotein autoantigens. Novel autoantigen structures identified were further characterized using nucleases and RNA hybridization. Human sera that recognize U1-70 kd (U1-70K) and La by immunoblotting also recognized multiple novel species when they were used to immunoblot lysates of UVB-irradiated keratinocytes or HeLa cells. These species were not present in control cells and were not observed when apoptosis was induced by Fas ligation or cytotoxic lymphocyte granule contents. Biochemical analysis using multiple assays revealed that these novel UVB-induced molecular species result from the covalent crosslinking between the U1 RNA and the hYRNA molecules with their associated proteins, including U1-70K, La, and likely components of the Sm particle. These data demonstrate that UVB irradiation of live cells can directly induce covalent RNA-protein complexes, which are recognized by human autoantibodies. As previously described for other autoantigens, these covalent complexes of RNA and proteins may have important consequences in terms of antigen capture and processing.

Induction of Senescence-Like Deterioration of Microsomal Membranes from Cauliflower by Free Radicals Generated during Gamma Irradiation 1

PubMed Central

Voisine, Richard; Vézina, Louis-P.; Willemot, Claude

1991-01-01

Membrane deterioration differs in aging and senescent tissues. Involvement of free radicals in the process is generally recognized. Little is known about the physiological effects of gamma irradiation on plant tissues. Degradation of microsomal membranes by the action of free radicals, generated in vivo by gamma rays, was investigated. Cauliflower florets (Brassica oleracea L., Botrytis group) were exposed to 2 or 4 kiloGray of gamma radiation. Membrane deterioration was assessed during 8-day storage at 13°C. Some senescence was indicated in nonirradiated controls by a parallel depletion of lipid phosphate and protein. Irradiation caused an immediate increase in tissue electrolyte leakage and a small increase in the free fatty acid content of membranes. In irradiated samples, leakage of electrolytes and the ratios of sterol to phospholipid and of free fatty acid to phospholipid increased with storage. During this period, membrane protein was progressively lost and the lipid phosphate-to-protein ratio increased markedly. Polyunsaturated fatty acids were selectively depleted from the free fatty acid fraction for all treatments, suggesting lipoxygenase activity. No change in lipid saturation was observed in the polar lipid fraction. The results suggest an enzyme-catalyzed senescence-like membrane deterioration, probably induced by chemical deesterification of phospholipids by free radicals generated during irradiation. PMID:16668433

Irradiation resistance of intravolume shading elements embedded in photomasks used for CD uniformity control by local intra-field transmission attenuation

NASA Astrophysics Data System (ADS)

Zait, Eitan; Ben-Zvi, Guy; Dmitriev, Vladimir; Oshemkov, Sergey; Pforr, Rainer; Hennig, Mario

2006-05-01

Intra-field CD variation is, besides OPC errors, a main contributor to the total CD variation budget in IC manufacturing. It is caused mainly by mask CD errors. In advanced memory device manufacturing the minimum features are close to the resolution limit resulting in large mask error enhancement factors hence large intra-field CD variations. Consequently tight CD Control (CDC) of the mask features is required, which results in increasing significantly the cost of mask and hence the litho process costs. Alternatively there is a search for such techniques (1) which will allow improving the intrafield CD control for a given moderate mask and scanner imaging performance. Currently a new technique (2) has been proposed which is based on correcting the printed CD by applying shading elements generated in the substrate bulk of the mask by ultrashort pulsed laser exposure. The blank transmittance across a feature is controlled by changing the density of light scattering pixels. The technique has been demonstrated to be very successful in correcting intra-field CD variations caused by the mask and the projection system (2). A key application criterion of this technique in device manufacturing is the stability of the absorbing pixels against DUV light irradiation being applied during mask projection in scanners. This paper describes the procedures and results of such an investigation. To do it with acceptable effort a special experimental setup has been chosen allowing an evaluation within reasonable time. A 193nm excimer laser with pulse duration of 25 ns has been used for blank irradiation. Accumulated dose equivalent to 100,000 300 mm wafer exposures has been applied to Half Tone PSM mask areas with and without CDC shadowing elements. This allows the discrimination of effects appearing in treated and untreated glass regions. Several intensities have been investigated to define an acceptable threshold intensity to avoid glass compaction or generation of color centers in the glass. The impact of the irradiation on the mask transmittance of both areas has been studied by measurements of the printed CD on wafer using a wafer scanner before and after DUV irradiation.

Effect of tube processing methods on microstructure, mechanical properties and irradiation response of 14YWT nanostructured ferritic alloys

DOE PAGES

Aydogan, E.; Maloy, S. A.; Anderoglu, O.; ...

2017-06-06

In this research, innovative thermal spray deposition (Process I) and conventional hot extrusion processing (Process II) methods have been used to produce thin walled tubing (~0.5 mm wall thickness) out of 14YWT, a nanostructured ferritic alloy. The effects of processing methods on the microstructure, mechanical properties and irradiation response have been investigated by using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and, micro- and nano-hardness techniques. It has been found that these two processes have a significant effect on the microstructure and mechanical properties of the as-fabricated 14YWT tubes. Even though both processing methods yield the formation of variousmore » size Y-Ti-O particles, the conventional hot extrusion method results in a microstructure with smaller, homogenously distributed nano-oxides (NOs, Y-Ti-O particles < 5 nm) with higher density. Therefore, Process II tubes exhibit twice the hardness of Process I tubes. It has also been found that these two tremendously different initial microstructures strongly affect irradiation response in these tubes under extremely high dose ion irradiations up to 1100 peak dpa at 450 °C. The finer, denser and homogenously distributed NOs in the Process II tube result in a reduction in swelling by two orders of magnitude. On the other hand, inhomogeneity of the initial microstructure in the Process I tube leads to large variations in both swelling and irradiation induced hardening. Moreover, hardening mechanisms before and after irradiation were measured and compared with detailed calculations. In conclusion, this study clearly indicates the crucial effect of initial microstructure on radiation response of 14YWT alloys.« less

Effect of tube processing methods on microstructure, mechanical properties and irradiation response of 14YWT nanostructured ferritic alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aydogan, E.; Maloy, S. A.; Anderoglu, O.

In this research, innovative thermal spray deposition (Process I) and conventional hot extrusion processing (Process II) methods have been used to produce thin walled tubing (~0.5 mm wall thickness) out of 14YWT, a nanostructured ferritic alloy. The effects of processing methods on the microstructure, mechanical properties and irradiation response have been investigated by using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and, micro- and nano-hardness techniques. It has been found that these two processes have a significant effect on the microstructure and mechanical properties of the as-fabricated 14YWT tubes. Even though both processing methods yield the formation of variousmore » size Y-Ti-O particles, the conventional hot extrusion method results in a microstructure with smaller, homogenously distributed nano-oxides (NOs, Y-Ti-O particles < 5 nm) with higher density. Therefore, Process II tubes exhibit twice the hardness of Process I tubes. It has also been found that these two tremendously different initial microstructures strongly affect irradiation response in these tubes under extremely high dose ion irradiations up to 1100 peak dpa at 450 °C. The finer, denser and homogenously distributed NOs in the Process II tube result in a reduction in swelling by two orders of magnitude. On the other hand, inhomogeneity of the initial microstructure in the Process I tube leads to large variations in both swelling and irradiation induced hardening. Moreover, hardening mechanisms before and after irradiation were measured and compared with detailed calculations. In conclusion, this study clearly indicates the crucial effect of initial microstructure on radiation response of 14YWT alloys.« less

Model predictive control of a solar-thermal reactor

NASA Astrophysics Data System (ADS)

Saade Saade, Maria Elizabeth

Solar-thermal reactors represent a promising alternative to fossil fuels because they can harvest solar energy and transform it into storable and transportable fuels. The operation of solar-thermal reactors is restricted by the available sunlight and its inherently transient behavior, which affects the performance of the reactors and limits their efficiency. Before solar-thermal reactors can become commercially viable, they need to be able to maintain a continuous high-performance operation, even in the presence of passing clouds. A well-designed control system can preserve product quality and maintain stable product compositions, resulting in a more efficient and cost-effective operation, which can ultimately lead to scale-up and commercialization of solar thermochemical technologies. In this work, we propose a model predictive control (MPC) system for a solar-thermal reactor for the steam-gasification of biomass. The proposed controller aims at rejecting the disturbances in solar irradiation caused by the presence of clouds. A first-principles dynamic model of the process was developed. The model was used to study the dynamic responses of the process variables and to identify a linear time-invariant model used in the MPC algorithm. To provide an estimation of the disturbances for the control algorithm, a one-minute-ahead direct normal irradiance (DNI) predictor was developed. The proposed predictor utilizes information obtained through the analysis of sky images, in combination with current atmospheric measurements, to produce the DNI forecast. In the end, a robust controller was designed capable of rejecting disturbances within the operating region. Extensive simulation experiments showed that the controller outperforms a finely-tuned multi-loop feedback control strategy. The results obtained suggest that our controller is suitable for practical implementation.

Effect of high-dose irradiation on quality characteristics of ready-to-eat chicken breast

NASA Astrophysics Data System (ADS)

Yun, Hyejeong; Haeng Lee, Kyung; Jung Lee, Hyun; Woon Lee, Ju; Uk Ahn, Dong; Jo, Cheorun

2012-08-01

High-dose (higher than 30 kGy) irradiation has been used to sterilize specific-purposed foods for safe and long-term storage. The objective of this study was to investigate the effect of high-dose irradiation on the quality characteristics of ready-to-eat chicken breast in comparison with those of the low-dose irradiation. Ready-to-eat chicken breast was manufactured, vacuum-packaged, and irradiated at 0, 5, and 40 kGy. The populations of total aerobic bacteria were 4.75 and 2.26 Log CFU/g in the samples irradiated at 0 and 5 kGy, respectively. However, no viable cells were detected in the samples irradiated at 40 kGy. On day 10, bacteria were not detected in the samples irradiated at 40 kGy but the number of bacteria in the samples irradiated at 5 kGy was increased. The pH at day 0 was higher in the samples irradiated at 40 kGy than those at 0 and 5 kGy. The 2-thiobarbituric acid reactive substance (TBARS) values of the samples were not significantly different on day 0. However, on day 10, the TBARS value was significantly higher in the samples irradiated at 40 kGy than those at 0 and 5 kGy. There was no difference in the sensory scores of the samples, except for off-flavor, which was stronger in samples irradiated at 5 and 40 kGy than control. However, no difference in off-flavor between the irradiated ones was observed. After 10 days of storage, only the samples irradiated at 40 kGy showed higher off-flavor score. SPME-GC-MS analysis revealed that 5 kGy of irradiation produced 2-methylbutanal and 3-methylbutanal, which were not present in the control, whereas 40 kGy of irradiation produced hexane, heptane, pentanal, dimethly disulfide, heptanal, and nonanal, which were not detected in the control or the samples irradiated at 5 kGy. However, the amount of compounds such as allyl sulfide and diallyl disulfide decreased significantly in the samples irradiated at 5 kGy and 40 kGy.

Control of campylobacter in poultry industry from farm to poultry processing unit: A review.

PubMed

Umaraw, Pramila; Prajapati, A; Verma, Akhilesh K; Pathak, V; Singh, V P

2017-03-04

Campylobacter is an emerging zoonotic bacterial threat in the poultry industry. Most of the human cases of campylobacteriosis recorded have revealed their poultry origins. Various control measures have been employed both at the farm and processing levels to combat with it. The antibiotic treatment, phage therapy, competitive exclusion, and vaccination have been adapted at the farm level to reduce colonization of Campylobacter in poultry gut. While prevention of intestinal spillage, scheduled slaughter, logistic slaughter, chemical decontamination of carcasses are recommended to reduce contamination during processing. The postharvest interventions such as heat treatment, freezing, irradiation of contaminated carcass can effectively reduce Campylobacter contamination. Thus, integrated approaches are required to tackle infection of Campylobacter in humans.

INFLUENCE OF INTRAMUSCULAR FAT LEVEL ON ORGANOLEPTIC, PHYSICAL, AND CHEMICAL CHARACTERISTICS OF IRRADIATED PORK. II. LOW-TEMPERATURE LONG-TIME PRE-IRRADIATION HEAT TREATMENT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bray, R.W.; Weckel, K.G.; Evans, G.W.

1964-02-01

Pork muscle (longissimus dorsi) was graded in three marbling levels by both visual appraisal and ether-extraction analysis of total fat. A low- temperature (121 deg F, gradually increasing to 191 deg F), long-time (19-hr) heat treatment was used for enzyme inactivation. Samples were packed under vacuum in rigid containers and irradiated to 4.5 Mrad with gamma radiation. Irradiated and frozen control samples were evaluated at intervals over a 180-day period. The heat treatment caused excessive connective-tissue breakdown as evidenced by a soft, dry texture. Marbling level had no significant effect on consumer-panel judgments of irradiated or frozen control samples (servedmore » plain, without bread). Lower degrees of marbling were preferred in irradiated sandwich items. Irradiated samples were less preferred than frozen control samples in both plain and sandwich form. Hunter L (color) values a/sub L/ (redness), hue, and saturation attributes were increased by irradiation treatment. Hunter L and b/sub L/ (yellowness) values of highly marbled irradiated sample-s were elevated. Highly marbled samples displayed greater tenderness qualities, as evidenced by mechanical tenderness measurements. Expressible moisture values were decreased by marbling degree and radiation treatment and increased by advancing storage time. As a measure of oxidation rancidity, thiobarbituric acid values were increased by increasing levels of marbling and advancing storage time, but were not influenced by preservation method. No significant differences in pH values due to marbling level or preservation method were detected. Bacteriologic counts of randomly selected irradiated samples indicated that they were commercially sterile (average of 57 colonies/g of sample). Methylene blue stains of colonles revealed Micrococcus. Frozen (control) samples contained moderate numbers of colonies (av. 2300 colonies per g of sample). Micrococcus colonies were again predominant, but a few colonles of film yeasts were also seen. Irradiated samples were negative for thermophilic anaerobic spores producing gas. Control samples were positive, containing gram-negative rods, Escherichia coli, and gram- positive cocci. (BBB)« less

One-step synthesis of gene carrier via gamma irradiation and its application in tumor gene therapy

PubMed Central

Kim, Eun-Ji; Heo, Hun; Park, Jong-Seok; Gwon, Hui-Jeong; Lim, Youn-Mook; Jang, Mi-Kyeong

2018-01-01

Introduction Although numerous studies have been conducted with the aim of developing drug-delivery systems, chemically synthesized gene carriers have shown limited applications in the biomedical fields due to several problems, such as low-grafting yields, undesirable reactions, difficulties in controlling the reactions, and high-cost production owing to multi-step manufacturing processes. Materials and methods We developed a 1-step synthesis process to produce 2-aminoethyl methacrylate-grafted water-soluble chitosan (AEMA-g-WSC) as a gene carrier, using gamma irradiation for simultaneous synthesis and sterilization, but no catalysts or photoinitiators. We analyzed the AEMA graft site on WSC using 2-dimensional nuclear magnetic resonance spectroscopy (2D NMR; 1H and 13C NMR), and assayed gene transfection effects in vitro and in vivo. Results We revealed selective grafting of AEMA onto C6-OH groups of WSC. AEMA-g-WSC effectively condensed plasmid DNA to form polyplexes in the size range of 170 to 282 nm. AEMA-g-WSC polyplexes in combination with psi-hBCL2 (a vector expressing short hairpin RNA against BCL2 mRNA) inhibited tumor cell proliferation and tumor growth in vitro and in vivo, respectively, by inducing apoptosis. Conclusion The simple grafting process mediated via gamma irradiation is a promising method for synthesizing gene carriers. PMID:29416333

Superpulsed (Ga-As, 904 nm) low-level laser therapy (LLLT) attenuates inflammatory response and enhances healing of burn wounds.

PubMed

Gupta, Asheesh; Keshri, Gaurav K; Yadav, Anju; Gola, Shefali; Chauhan, Satish; Salhan, Ashok K; Bala Singh, Shashi

2015-06-01

Low-level laser therapy (LLLT) using superpulsed near-infrared light can penetrate deeper in the injured tissue and could allow non-pharmacological treatment for chronic wound healing. This study investigated the effects of superpulsed laser (Ga-As 904 nm, 200 ns pulse width; 100 Hz; 0.7 mW mean output power; 0.4 mW/cm(2) average irradiance; 0.2 J/cm(2) total fluence) on the healing of burn wounds in rats, and further explored the probable associated mechanisms of action. Irradiated group exhibited enhanced DNA, total protein, hydroxyproline and hexosamine contents compared to the control and silver sulfadiazine (reference care) treated groups. LLLT exhibited decreased TNF-α level and NF-kB, and up-regulated protein levels of VEGF, FGFR-1, HSP-60, HSP-90, HIF-1α and matrix metalloproteinases-2 and 9 compared to the controls. In conclusion, LLLT using superpulsed 904 nm laser reduced the inflammatory response and was able to enhance cellular proliferation, collagen deposition and wound contraction in the repair process of burn wounds. Photomicrographs showing no, absence inflammation and faster wound contraction in LLLT superpulsed (904 nm) laser treated burn wounds as compared to the non-irradiated control and silver sulfadiazine (SSD) ointment (reference care) treated wounds. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Study of the effect of gamma irradiation on a commercial polycyclooctene I. Thermal and mechanical properties

NASA Astrophysics Data System (ADS)

García-Huete, N.; Laza, J. M.; Cuevas, J. M.; Vilas, J. L.; Bilbao, E.; León, L. M.

2014-09-01

A gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical, chemical and mechanical properties. Gamma irradiation originates free radicals able to induce chain scission or recombination of radicals, which induces annihilation, branching or crosslinking processes. The aim of this work is to research the structural, thermal and mechanical changes induced on a commercial polycyclooctene (PCO) when it is irradiated with a gamma source of 60Co at different doses (25-200 kGy). After gamma irradiation, gel content was determined by Soxhlet extraction in cyclohexane. Furthermore, thermal properties were evaluated before and after Soxhlet extraction by means of Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC), as well as mechanical properties were measured by Dynamic Mechanical Thermal Analysis (DMTA). The results showed the variations of the properties depending on the irradiation dose. Finally, a first approach to evaluate qualitatively the shape memory behaviour of all irradiated PCO samples was performed by a visually monitoring shape recovery process.

Recovery of uranium from an irradiated solid target after removal of molybdenum-99 produced from the irradiated target

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reilly, Sean Douglas; May, Iain; Copping, Roy

A process for minimizing waste and maximizing utilization of uranium involves recovering uranium from an irradiated solid target after separating the medical isotope product, molybdenum-99, produced from the irradiated target. The process includes irradiating a solid target comprising uranium to produce fission products comprising molybdenum-99, and thereafter dissolving the target and conditioning the solution to prepare an aqueous nitric acid solution containing irradiated uranium. The acidic solution is then contacted with a solid sorbent whereby molybdenum-99 remains adsorbed to the sorbent for subsequent recovery. The uranium passes through the sorbent. The concentrations of acid and uranium are then adjusted tomore » concentrations suitable for crystallization of uranyl nitrate hydrates. After inducing the crystallization, the uranyl nitrate hydrates are separated from a supernatant. The process results in the purification of uranyl nitrate hydrates from fission products and other contaminants. The uranium is therefore available for reuse, storage, or disposal.« less

Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

NASA Astrophysics Data System (ADS)

Ribeiro, J.; Cavaglieri, L.; Vital, H.; Cristofolini, A.; Merkis, C.; Astoreca, A.; Orlando, J.; Carú, M.; Dalcero, A.; Rosa, C. A. R.

2011-05-01

The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B 1 and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

The post-thaw irradiation of avian spermatozoa with He-Ne laser differently affects chicken, pheasant and turkey sperm quality.

PubMed

Iaffaldano, N; Paventi, G; Pizzuto, R; Passarella, S; Cerolini, S; Zaniboni, L; Marzoni, M; Castillo, A; Rosato, M P

2013-11-30

The effects of post-thaw Helium-Neon (He-Ne) laser irradiation on mobility and functional integrity of frozen/thawed chicken, pheasant and turkey spermatozoa were investigated. Cytochrome C oxidase (COX) activity was also determined as a measure of the effect of irradiation on mitochondrial bioenergetics. Semen samples from each species were collected, processed and frozen according to the pellet procedure. After thawing, each semen sample was divided into two subsamples: the first one was the control; the second one was irradiated with a single mode continuous He-Ne laser wave (wavelength 632.8 nm; 6 mW; 3.96 J/cm(2)). Then the samples were assessed for sperm mobility (Accudenz(®) swim-down test), viability (SYBR-14/PI staining), osmotic-resistance (HOS test) and COX activity. The irradiation was effective P<0.05 increasing sperm motility in the turkey semen (0.228 ± 0.01 compared with 0.294 ± 0.02). The irradiation also caused an increase (P<0.05) of the COX activity in pheasant (+135 ± 4%) and turkey (+116 ± 4%) sperm, without affecting viability and osmotic-resistance. The COX was positively correlated (P<0.05) with the viability of chicken sperm, however no significant interactions were found between mobility and COX activity in the three avian species. Due to the difference in energetic metabolism among avian species used in this study, the He-Ne laser irradiation has a differential action on bio-stimulation of turkey, chicken and pheasant spermatozoa. The present results are the first to elucidate the possibility for restoration of motility of cryopreserved avian spermatozoa by bio-stimulation provided via He-Ne laser irradiation. Copyright © 2013 Elsevier B.V. All rights reserved.

77 FR 29352 - Agency Information Collection Activities; Proposed Collection; Comment Request; Irradiation in...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-17

...] Agency Information Collection Activities; Proposed Collection; Comment Request; Irradiation in the... information collection provisions of FDA's requirements for food irradiation processors. DATES: Submit either... of information technology. Irradiation in the Production, Processing, and Handling of Food--21 CFR...

Current status and prospects of radiation processing studies in Taiwan, R. O. C.

NASA Astrophysics Data System (ADS)

Fu, Ying-Kai

The research on radiation processing in past 5 years in Taiwan covers industrial application of radiation-induced polymerization and curing, medical application of radiosterilization of medical supplies, chemicals, and amniotic membrane for wound dressing as well as agricultural application of food irradiation and genogenesis etc. Radiation-induced polymerization applied on wood and bamboo plastic composite of methyl methacrylate, radiation curing on polyurethane and silicon rubber for biomedical material using to separate oxygen from nitrogen and on crosslinking of pp and ps for artificial skin for wound dressing were all success. Radio-sterilization of disposable medical supplies appears for immediate application after the studies of the dose requirement of several radioresistant microorganisms, dose distribution measured by chemical dosimeters of ceric sulfate and Fricke dosimeter as well as quality control system were completed. The radiosterilization study of tetracycline - HCl and few detoxic agents like atropine sulfate and toxogonin has shown the promising results on radiosterilization of chemicals, the radiosterilization of amniotic membrane for wound dressing are also success. Food irradiation on sprouting inhibition of potatoes, garlic etc, on radiodisinfestation of cereal insects, tobacco bettles, soybean insects, and flour beetles, as well as on frog legs and porks have been also discussed. The legislation on radiosterilization of medical supplies and food irradiation of 14 items has been approved by National Health Administration, R.O.C. in July of 1982 and January of 1985 respectively. Even 24 hrs-operation of 1 Mega curie irradiation plant at INER can not satisfy the requirement of radiosterilization of medical supplies. A private commercial irradiation plant is urgently needed in Taiwan other than at INER now.

Factors affecting ultraviolet-A photon emission from β-irradiated human keratinocyte cells.

PubMed

Le, M; Mothersill, C E; Seymour, C B; Ahmad, S B; Armstrong, A; Rainbow, A J; McNeill, F E

2015-08-21

The luminescence intensity of 340±5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to (90)Y β-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from β-irradiated cells. Exposure of 1 x 10(4) cells/5 mL to 703 μCi resulted in maximum UVA photoemission at 44.8 x 10(3)±2.5 x 10(3) counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for (90)Y activities 14 to 703 μCi where a positive relationship between photoemission and (90)Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1 x 10(4) cells/5 mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low β activities (⩽400 μCi). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

The effect of standard and high-fluence corneal cross-linking (CXL) on cornea and limbus.

PubMed

Richoz, Olivier; Tabibian, David; Hammer, Arthur; Majo, François; Nicolas, Michael; Hafezi, Farhad

2014-07-22

When treating peripheral ectatic disease-like pellucid marginal degeneration (PMD), corneal cross-linking with UV-A and riboflavin (CXL) must be applied eccentrically to the periphery of the lower cornea, partly irradiating the corneal limbus. Here, we investigated the effect of standard and double-standard fluence corneal cross-linking with riboflavin and UV-A (CXL) on cornea and corneal limbus in the rabbit eye in vivo. Epithelium-off CXL was performed in male New Zealand White rabbits with two irradiation diameters (7 mm central cornea, 13 mm cornea and limbus), using standard fluence (5.4 J/cm(2)) and double-standard fluence (10.8 J/cm(2)) settings. Controls were subjected to epithelial removal and riboflavin instillation, but were not irradiated with UV-A. Following CXL, animals were examined daily until complete closure of the epithelium, and at 7, 14, 21, and 28 days. Animals were killed and a corneoscleral button was excised and processed for light microscopy and immunohistochemistry. For both irradiation diameters and fluences tested, no signs of endothelial damage or limbal vessel thrombosis were observed, and time to re-epithelialization was similar to untreated controls. Histological and immunohistochemical analysis revealed no differences in the p63 putative stem cell marker expression pattern. Even when using fluence twice as high as the one used in current clinical CXL settings, circumferential UV-A irradiation of the corneal limbus does not alter the regenerative capacity of the limbal epithelial cells, and the expression pattern of the putative stem cell marker p63 remains unchanged. This suggests that eccentric CXL may be performed safely in PMD. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Influence of different iodinated contrast media on the induction of DNA double-strand breaks after in vitro X-ray irradiation.

PubMed

Deinzer, Christoph K W; Danova, Daniela; Kleb, Beate; Klose, Klaus J; Heverhagen, Johannes T

2014-01-01

The objective of this work was to examine differences in DNA double-strand break induction in peripheral blood lymphocytes after in vitro X-ray irradiation between iodinated contrast agents. Four different iodinated X-ray contrast agents--three of them with two different iodine concentrations--and mannitol (negative control; concentration of 150 mg mannitol per ml blood) were pipetted into blood samples so that there was a concentration of 0, 7.5 or 15 mg of iodine per ml blood in the samples. Negative controls without contrast medium (0 mg of iodine per ml blood) were also processed for every irradiation dose. The tubes were exposed to 0, 20 or 500 mGy in vitro X-ray irradiation. After that, the lymphocytes were separated by using density-gradient centrifugation. Fluorescence microscopy was applied to determine the average number of γH2AX-foci per lymphocyte in the presence or absence of different contrast media or mannitol. Differences in the number of γH2AX-foci were statistically analysed by one-way ANOVA and post-hoc Tukey's honestly significant difference test. Iodinated contrast agents led to a statistically significant increase in DNA double-strand breaks after in vitro irradiation. This effect increased statistically significant with rising radiation dose and appeared independent of the contrast agent used (iopromid, iodixanol, iomeprol, iopamidol). A statistically significant difference in DNA damage between the different tested contrast agents was not found. Therefore, the increase in DNA double-strand breaks depends solely on the amount of iodine applied. For evaluation of clinical consequences, our findings could be tested in further animal studies. Copyright © 2014 John Wiley & Sons, Ltd.

THE ABSCOPAL EFFECT OF X IRRADIATION ON BONE GROWTH IN RATS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pappas, A.M.; Cohen, J.

1963-06-01

The abscopal effect of irradiation (that which is evident at a distance from the irradiated volume but within the same organism) was investigated in rats. It was possible to demonstrate the effects on growth locally and abscopally when x-ray doses of 400 and 800 r were delivered to the lower extremity and when 800 r was delivered to the knee alone. A distinction between abscopal effects after local irradiation and systemic effects after whole-body irradiation is discussed. The weights of control and irradiated animals were similar for the first 21 days, during which period they did not exhibit any untowardmore » effects of irradiation. However, after 21 days there was a decrease in weight gain, which persisted until the 72nd day. Group A (controls) was the heaviest group, with a mean weight of 412 g. Group B (800 r to the left hind extremity) had a mean weight of 378. Group C (400 r to the left hind extremity) and Group D (800 r to the left knee) exhibited mean weights of 391 and 394 g, respectively. Roentgenographic measurements revealed that all animals receiving irradiation had retardation in the growth of the irradiated tibiae, which were shorter than both the control and the contralateral (unirradiated) tibiae. Only the animals that had received 800 r to their leff hind extremity showed significant differences in the lengths of their unirradiated bones compared with the bones of the control animals of Group A, that is, a significant abscopal growth retardation. Although the abscopal effect appeared to be associated with the volume of tissue irradiated, the way this effect is mediated is not known. The weight gains of the animals demonstrated a strong association between decrease in weight gain, the volume of tissue irradiated, and the dose administered. The impaired weight gsin roughly paralleled the abscopal retardation of bone growth. The animals which received the highest dose of irradiation, 800 r, to the largest volume of tissue, 10% of the body volume, revealed the greatest deviation from the control group. It is concluded that irradiation effects in animals are composites of the responses of the whole organism to the injury, of the responses of local tissues, and vessels at their level of tissue organization, and of the responses of individual cells. All of these responses may be interdependent. The evidence indicates that a systemic inhibition of all bone growth and weight gain occurs when a sufficient volume of tissue is irradiated at a sufficiently high dosage. (BBB)« less

Modification of WS2 nanosheets with controllable layers via oxygen ion irradiation

NASA Astrophysics Data System (ADS)

Song, Honglian; Yu, Xiaofei; Chen, Ming; Qiao, Mei; Wang, Tiejun; Zhang, Jing; Liu, Yong; Liu, Peng; Wang, Xuelin

2018-05-01

As one kind of two-dimensional materials, WS2 nanosheets have drawn much attention with different kinds of research methods. Yet ion irradiation method was barely used for WS2 nanosheets. In this paper, the structure, composition and optical band gap (Eg) of the multilayer WS2 films deposited by chemical vapor deposition (CVD) method on sapphire substrates before and after oxygen ion irradiation with different energy and fluences were studied. Precise tailored layer-structures and a controllable optical band gap of WS2 nanosheets were achieved after oxygen ion irradiation. The results shows higher energy oxygen irradiation changed the shape from triangular shaped grains to irregular rectangle shape but did not change 2H-WS2 phase structure. The intensity of E2g1 (Г) and A1g (Г) modes decreased and have small shifts after oxygen ion irradiation. The peak frequency difference between the E2g1 (Г) and A1g (Г) modes (Δω) decreased after oxygen ion irradiation, and this result indicates the number of layers decreased after oxygen ion irradiation. The Eg decreased with the increase of the energy and the fluence of oxygen ions. The number of layers, thickness and optical band gap changed after ion irradiation with different ion fluences and energies. The results proposed a new strategy for precise control of multilayer nanosheets and demonstrated the high applicability of ion irradiation in super-capacitors, field effect transistors and other applications.

Effects of processing treatment and sorbate addition on the flavor characteristics of apple cider.

PubMed

Boylston, Terri D; Wang, Hui; Reitmeier, Cheryll A; Glatz, Bonita A

2003-03-26

Processing treatments used to produce a microbiologically "safe" apple cider were evaluated to determine the impact of these treatments on the overall flavor characteristics. Apple cider with (0.1%) and without (0%) potassium sorbate was subjected to four processing treatments: untreated, irradiated at 2 kGy, irradiated at 4 kGy, and pasteurized. Volatile flavor compounds were isolated from the cider using solid-phase microextraction methods with gas chromatographic analysis. A trained descriptive analysis panel evaluated sensory attributes. The effects of the processing treatment were dependent on the presence of sorbate in the apple cider. Irradiation treatments resulted in a decrease in the content of esters characteristic of apple flavor and an increase in the content of alcohols and aldehydes formed through lipid oxidation reactions. The presence of sorbate reduced the effects of the irradiation treatments on these volatile flavor compounds. Sensory panelists, however, detected higher intensities of undesirable flavor attributes, including "cardboard flavor", and lower intensities of the desirable "apple flavor" in irradiated cider with added sorbate.

Influence of the fractioned irradiation energy in the phototherapy with low intensity laser on the growth of human dental pulp fibroblasts

NASA Astrophysics Data System (ADS)

Meneguzzo, D. T.; Eduardo, C. P.; Ribeiro, M. S.; Marques, M. M.

2008-03-01

Laser phototherapy has proven to improve treatment of several pathologies in dentistry. The aim of the present study was to analyze the low power laser phototherapy effects comparing multiple irradiations with the same total energy at once. This in vitro study focuses on the biostimulation of cellular growth of pulp fibroblasts (FP5 cell lineage). The cells were grown in Dulbecco's Modified Eagle's (DME) medium with either 5% (nutritional deficit) or 10% fetal bovine serum (FBS). Laser irradiation was carried out with diode lasers with the following parameters: 685 nm, 40 mW, spot size 0.019 cm2. The groups were: G1(6.3J/cm2, 3 s, 0.12J), G2 (12.6J/cm2, 6 s, 0.24J), G3 (18.9J/cm2, 9 s, 0.36J), G4 (2 irradiations of 6.3J/cm2, 0.24J), G5 (3 irradiations of 6.3J/cm2, 0.36J), G6 (5% SFB, negative control, without irradiation), and G7 (10% SFB, positive control, without irradiation). On groups G4 and G5 the irradiation was performed with 6h-intervals. For growth analysis, the MTT test was used 24 hours after the last irradiation. The data from spectrophotometer were analyzed by ANOVA followed by the Tukey's test. The groups submitted to multiple irradiations presented significantly higher cell growth than the groups with single irradiation. This cell growth was similar to that of positive control group. The laser phototherapy with multiple irradiations is more effective on cellular growth.

Laser Consolidation - A Novel One-Step Manufacturing Process for Making Net-Shape Functional Components

DTIC Science & Technology

2006-05-01

dies. This process uses a laser beam to melt a controlled amount of injected powder on a base plate to deposit the first layer and on previous passes...Consolidation” to build functional net-shape components directly from metallic powder in one step [1-3]. The laser consolidation is a one-step computer-aided...A focused laser beam is irradiated on the substrate to create a molten pool, while metallic powder is injected simultaneously into the pool. A

Paraneoplastic Syndromes

MedlinePlus

... cortisone or prednisone, high-dose intravenous immunoglobulin, or irradiation. Plasmapheresis, a process that cleanses antibodies from the ... cortisone or prednisone, high-dose intravenous immunoglobulin, or irradiation. Plasmapheresis, a process that cleanses antibodies from the ...

Performance of the HIMAC beam control system using multiple-energy synchrotron operation

NASA Astrophysics Data System (ADS)

Mizushima, K.; Furukawa, T.; Iwata, Y.; Hara, Y.; Saotome, N.; Saraya, Y.; Tansho, R.; Sato, S.; Fujimoto, T.; Shirai, T.; Noda, K.

2017-09-01

Multiple-energy synchrotron operation was developed to realize fast 3D scanning irradiation for carbon-ion radiotherapy. This type of operation can output various carbon-ion beams with different energies in a single synchrotron cycle. The beam control system used in this kind of operation was developed to quickly provide the beam energy and intensity required from the irradiation control system. The performance of the system was verified by experimental tests. The system could output beams of 197 different energies in 63 s. The beam intensity could be controlled for all the output beams without large ripples or overshooting. The experimental test of irradiation for prostate cancer treatment was also successfully performed, and the test results proved that our system can greatly reduce the irradiation time.

10 CFR 36.23 - Access control.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Access control. 36.23 Section 36.23 Energy NUCLEAR... Requirements for Irradiators § 36.23 Access control. (a) Each entrance to a radiation room at a panoramic... radiation room at a panoramic irradiator must have an independent backup access control to detect personnel...

10 CFR 36.23 - Access control.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Access control. 36.23 Section 36.23 Energy NUCLEAR... Requirements for Irradiators § 36.23 Access control. (a) Each entrance to a radiation room at a panoramic... radiation room at a panoramic irradiator must have an independent backup access control to detect personnel...

10 CFR 36.23 - Access control.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Access control. 36.23 Section 36.23 Energy NUCLEAR... Requirements for Irradiators § 36.23 Access control. (a) Each entrance to a radiation room at a panoramic... radiation room at a panoramic irradiator must have an independent backup access control to detect personnel...

Food processors requirements met by radiation processing

NASA Astrophysics Data System (ADS)

Durante, Raymond W.

2002-03-01

Processing food using irradiation provides significant advantages to food producers by destroying harmful pathogens and extending shelf life without any detectable physical or chemical changes. It is expected that through increased public education, food irradiation will emerge as a viable commercial industry. Food production in most countries involves state of the art manufacturing, packaging, labeling, and shipping techniques that provides maximum efficiency and profit. In the United States, food sales are extremely competitive and profit margins small. Most food producers have heavily invested in equipment and are hesitant to modify their equipment. Meat and poultry producers in particular utilize sophisticated production machinery that processes enormous volumes of product on a continuous basis. It is incumbent on the food irradiation equipment suppliers to develop equipment that can easily merge with existing processes without requiring major changes to either the final food product or the process utilized to produce that product. Before a food producer can include irradiation as part of their food production process, they must be certain the available equipment meets their needs. This paper will examine several major requirements of food processors that will most likely have to be provided by the supplier of the irradiation equipment.

Low-angle X-ray scattering properties of irradiated spices

NASA Astrophysics Data System (ADS)

Almeida, A. P. G.; Braz, D.; Barroso, R. C.; Lopes, R. T.

2007-09-01

The scattering of X-rays at low angles (LAXS) is a technique dominated by the coherent scattering process. One characteristic observation of low-angle coherent scattering is the so-called molecular interference effect, being characterized by the presence of one or more peaks in the forward direction of scattering. In the present study, LAXS profiles from five different spices are carefully measured in order to establish characteristic scattering signatures. Samples of Ceylon cinnamon, cumin, nutmeg, paprika and black pepper were bought in local market in Rio de Janeiro, Brazil. The LAXS patterns were obtained using a Shimadzu DRX 6000 diffractometer in reflection geometry. Coherent scattering patterns are measured for the samples for θ=5-35°. The data were collected in 0.05° increments every 3 s. In order to evaluate the possible molecular structure changes caused to the irradiation procedure, the signatures obtained for control (non-irradiated) spices were compared with spice samples irradiated with different doses varying from 3 to 40 kGy. The LAXS patterns of all samples were obtained after 30, 60, 90, 120 days to evaluate the effect of storage period. Scattering profiles from spices irradiated with different irradiation doses were obtained and the results compared. For each spice, there is no considerable deviation in shape in function of the irradiation dose. It indicates that the molecular structure of each analyzed spices is preserved considering the dose range chosen. The results show that the molecular structure was found to be stable during storage at the ambient temperature for up to 4 months.

Microbiological and biochemical characteristics of ground beef as affected by gamma irradiation, food additives and edible coating film

NASA Astrophysics Data System (ADS)

Ouattara, B.; Giroux, M.; Yefsah, R.; Smoragiewicz, W.; Saucier, L.; Borsa, J.; Lacroix, M.

2002-03-01

The current interest in "minimally processed foods" has attracted the attention for combination of mild treatments to improve food safety and shelf-life extention. The present study was conducted to evaluate the combined effect of gamma irradiation and incorporation of naturally occurring antimicrobial compounds on microbial and biochemistry characteristics of ground beef. Ground beef patties (23% fat ) were purchased from a local grocery store (IGA, Laval, Que., Canada) and divided into 3 separate treatment groups: (i) control (ground beef without additive), (ii) ground beef with 0.5% (w/w) ascorbic acid, and (iii) ground beef with 0.5% ascorbic acid and coated with a protein-based coating containing selected spices. Samples were irradiated at 0, 1, 2, and 3 kGy final dose at the CIC. Samples were stored at 4°C and evaluated periodically for microbial growth, total thiobarbituric reactive substances (TBARS) and free sulfydryl content. At the end of the storage period, Enterobacteriaceae, Lactic acid bacteria, Pseudomonas and Brochothrix thermosphacta were enumerated. Regardless of the treatment group, irradiation significantly ( p⩽0.05) reduced the total aerobic plate counts (APC). Irradiation doses of 1, 2, and 3 kGy produced immediate reduction of 2, 3, and 4 log units of APCs, respectively. Also, shelf-life periods were higher for ground beef samples containing food additives. Lactic acid bacteria and Brochothrix thermosphacta were more resistant to irradiation than Enterobacteriaceae and Pseudomonas. Concentration of TBARS and free sulfydryl concentrations were stabilized during post-irradiation storage for samples containing ascorbic acid and coated with the protein-based coating containing spices.

Effects of telmisartan and losartan on irradiated testes.

PubMed

da Silva Mansano, Naira; Jorge, Isabela Fernandes; Chies, Agnaldo Bruno; Viani, Gustavo Arruda; Spadella, Maria Angélica

2018-02-01

To analyze the effects of radiation on the reproductive tissue of male Wistar rats and to evaluate whether treatment with the Ang II AT1 receptor antagonists telmisartan and losartan mitigate the dysfunctions resulting from this exposure. Rats were randomly divided into groups: Control, Irradiated, Telmisartan, Losartan, Irradiated+Telmisartan, and Irradiated+Losartan. Single dose of 5Gy was administered directly into the scrotum, followed by treatment with telmisartan (12mg/kg/day) or losartan (34mg/kg/two times/day) for 60days. Testicular function parameters were evaluated from spermatozoa of the vas deferens. Testes were processed for histopathological and morphometric-stereological analysis. Proliferating cell nuclear antigen (PCNA) immunohistochemistry was evaluated. Radiation significantly reduced sperm motility, concentration, vitality, and increased the number of abnormal spermatozoa. Telmisartan and losartan did not significantly prevent these radiation-induced disorders. Seminiferous tubules were atrophied in both untreated and treated irradiated testes, and exhibited vacuoles, increased interstitial tissue and high number of blood vessels. However, several seminiferous tubules in recuperation were founded among damaged tubules in the testes of treated animals. The PCNA immunohistochemistry confirmed these outcomes. PCNA-positive cells were detected in dividing spermatogonia and spermatocytes from irradiated telmisartan and losartan treated rats whereas in the only-irradiated group, PCNA staining was observed in the nuclei of only the surviving spermatogonia. Under these experimental conditions, the testicular function parameters showed that radiation produced marked damage that was not reversed by treatments. However, gonadal restructuring and recovery of spermatogenesis in treated animals may to reflect attenuation of radiation-induced damages and potential start of recovery. Copyright © 2017 Elsevier Inc. All rights reserved.

IRRADIATION OF EGGS AND EGG PRODUCTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brooks, J.; Hannan, R.S.; Hobbs, B.C.

It has been known for some time that egg products may contain members of the Salmonella group capable of causing food poisoning, and the position has been rendered more serious by the recent discovery of S. paratyphi B in some of the samples of egg products. Attempts to destroy salmonellae in liquid egg by pasteurization before freezing or drying have met with considerable success but the process requires careful control. The tins in which the frozen product is distributed hold up to 20 kg, and are therefore of a size suitable for treatment with gamma -radiation. After treatment of smallmore » samples of frozen whole egg with 2 Mev cathode rays it was concluded that a dose of about O.3 to 0.5 Mrad would destroy the numbers of salmonellae normally encountered in the product without impairing the baking qualities of the material. Whole tins, each containing 10 kg of infected material, were therefore irradiated in the frozen state with Co/sup 60/ gamma -rays. Two tins were treated at each of three dose levels of 0.3, 0.4, and 0.5 Mrad. No salmonellae were detected in duplicate samples of 25 g of material taken from each of the tins after irradiation. If the effectiveness of the treatment is confirmed, the process has obvious attractions since it dispenses with the need to thaw or otherwise to handle the product. The paper also contains a general discussion on the irradiation of eggs and egg products. (auth)« less

Swift heavy ion irradiation reduces porous silicon thermal conductivity

NASA Astrophysics Data System (ADS)

Massoud, M.; Canut, B.; Newby, P.; Frechette, L.; Chapuis, P. O.; Bluet, J. M.

2014-12-01

While the electrical conductivity of semiconductors can be easily changed over order of magnitudes (8 in silicon) by playing on the doping, the thermal conductivity (TC) control is a challenging issue. Nevertheless, numerous applications require TC control in Si down to 1 W m-1 K-1. Among them, there are thermal insulation requirements in MEMS, thermal management issues in 3D packaging or TC reduction for thermoelectric applications. Towards this end, the formation of nanoporous Si by electrochemical anodisation is efficient. Nevertheless, in this case the material is too fragile for MEMS application or even to withstand CMOS technological processes. In this work, we show that ion irradiation in the electronic regime is efficient for reducing TC in meso-porous Si (PSi), which is more mechanically robust than the nanoporous PSi. We have studied three different mass to energy ratios (238U at 110 MeV and 130Xe at 91 MeV and 29 MeV) with fluences ranging from 1012 cm-2 to 7 × 1013 cm-2. The sample properties, after irradiation, have been measured by infrared spectroscopy, Raman spectroscopy and scanning electron microscopy. The TC has been measured using scanning thermal microscopy. Although, bulk Si is insensitive to ion interaction in the electronic regime, we have observed the amorphisation of the PSi resulting in a TC reduction even for the low dose and energy. For the highest irradiation dose a very important reduction factor of four was obtained.

Effect of irradiation on queen survivorship and reproduction in the invasive fire ant Solenopsis invicta,(Hymenoptera: Formicidae) and a generic phytosanitary irradiation treatment for ants

USDA-ARS?s Scientific Manuscript database

Ants are common hitchhiker pests on traded agricultural commodities that could be controlled by postharvest irradiation treatment. We studied radiation tolerance in queens of the red imported fire ant Solenopsis invicta Buren to determine the dose sufficient for its control. Virgin or fertile queens...

Effects of high-intensity pulse irradiation with linear polarized near-infrared rays and stretching on muscle tone in patients with cerebrovascular disease: a randomized controlled trial.

PubMed

Takeuchi, Nobuyuki; Takezako, Nobuhiro; Shimonishi, Yuko; Usuda, Shigeru

2017-08-01

[Purpose] The purpose of this study was to clarify the influence of high-intensity pulse irradiation with linear polarized near-infrared rays (HI-LPNR) and stretching on hypertonia in cerebrovascular disease patients. [Subjects and Methods] The subjects were 40 cerebrovascular disease patients with hypertonia of the ankle joint plantar flexor muscle. The subjects were randomly allocated to groups undergoing treatment with HI-LPNR irradiation (HI-LPNR group), stretching (stretching group), HI-LPNR irradiation followed by stretching (combination group), and control group (10 subjects each). In all groups, the passive range of motion of ankle dorsiflexion and passive resistive joint torque of ankle dorsiflexion were measured before and after the specified intervention. [Results] The changes in passive range of motion, significant increase in the stretching and combination groups compared with that in the control group. The changes in passive resistive joint torque, significant decrease in HI-LPNR, stretching, and combination groups compared with that in the control group. [Conclusion] HI-LPNR irradiation and stretching has effect of decrease muscle tone. However, combination of HI-LPNR irradiation and stretching has no multiplier effect.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schuster, J.J.; Stryker, J.A.; Demers, L.M.

The pathophysiology of chronic radiation-induced diarrhea was evaluated in 28 patients who had undergone pelvic irradiation for gynecologic neoplasms 2 to 7 years previously. Twenty-seven patients undergoing radiotherapy with techniques that did not require abdominal or pelvic irradiation served as controls. The glycine conjugates of cholic acid (GC) were measured in serum by radioimmunoassay. Fasting and 2 hr. pp GC levels for the pelvic irradiated patients were 11.0 +/- 11.1 (mean +/- SD) and 24.8 +/- 17.3 micrograms/dl. Fasting and 2 hr. pp GC levels for controls were 12.6 +/- 7.4 and 28.0 +/- 14.7. There were no significant differencesmore » in the post-prandial increases in serum GC between pelvic irradiated patients and controls (p = .23, Type II error probability = .13). There was also no significant difference in the 2 hr. pp and fasting GC ratio (p = .39). There was significant difference between the stool frequency (p less than .01) and the prevalence of diarrhea (p less than .02) between pelvic irradiated patients and controls. The data suggest that bile acid malabsorption due to ileal dysfunction is not an inevitable late complication of pelvic irradiation and is not the major determinant in the pathophysiology of chronic radiation-induced diarrhea.« less

Method for analyzing passive silicon carbide thermometry with a continuous dilatometer to determine irradiation temperature

DOE PAGES

Campbell, Anne A.; Porter, Wallace D.; Katoh, Yutai; ...

2016-01-14

Silicon carbide is used as a passive post-irradiation temperature monitor because the irradiation defects will anneal out above the irradiation temperature. The irradiation temperature is determined by measuring a property change after isochronal annealing, i.e., lattice spacing, dimensions, electrical resistivity, thermal diffusivity, or bulk density. However, such methods are time-consuming since the steps involved must be performed in a serial manner. This work presents the use of thermal expansion from continuous dilatometry to calculate the SiC irradiation temperature, which is an automated process requiring minimal setup time. Analysis software was written that performs the calculations to obtain the irradiation temperaturemore » and removes possible user-introduced error while standardizing the analysis. In addition, this method has been compared to an electrical resistivity and isochronal annealing investigation, and the results revealed agreement of the calculated temperatures. These results show that dilatometry is a reliable and less time-intensive process for determining irradiation temperature from passive SiC thermometry.« less

Method for analyzing passive silicon carbide thermometry with a continuous dilatometer to determine irradiation temperature

NASA Astrophysics Data System (ADS)

Campbell, Anne A.; Porter, Wallace D.; Katoh, Yutai; Snead, Lance L.

2016-03-01

Silicon carbide is used as a passive post-irradiation temperature monitor because the irradiation defects will anneal out above the irradiation temperature. The irradiation temperature is determined by measuring a property change after isochronal annealing, i.e., lattice spacing, dimensions, electrical resistivity, thermal diffusivity, or bulk density. However, such methods are time-consuming since the steps involved must be performed in a serial manner. This work presents the use of thermal expansion from continuous dilatometry to calculate the SiC irradiation temperature, which is an automated process requiring minimal setup time. Analysis software was written that performs the calculations to obtain the irradiation temperature and removes possible user-introduced error while standardizing the analysis. This method has been compared to an electrical resistivity and isochronal annealing investigation, and the results revealed agreement of the calculated temperatures. These results show that dilatometry is a reliable and less time-intensive process for determining irradiation temperature from passive SiC thermometry.

Shear bond, wettability and AFM evaluations on CO2 laser-irradiated CAD/CAM ceramic surfaces.

PubMed

El Gamal, Ahmed; Medioni, Etienne; Rocca, Jean Paul; Fornaini, Carlo; Muhammad, Omid H; Brulat-Bouchard, Nathalie

2017-05-01

The purpose of this study is to determine the CO 2 laser irradiation in comparison with sandblasting (Sb), hydrofluoric acid (Hf) and silane coupling agent (Si) on shear bond strength (SBS), roughness (Rg) and wettability (Wt) of resin cement to CAD/CAM ceramics. Sixty (CAD/CAM) ceramic discs were prepared and distributed into six different groups: group A, control lithium disilicate (Li); group B, control zirconia (Zr); group C, Li: CO 2 /HF/Si; group D, Li: HF/Si; group E, Zr: CO 2 /Sb/Si; group F, Zr: Sb/Si. Result showed significant difference between irradiated and non-irradiated in terms of shear bond strength for zirconia ceramics (p value = 0.014). Moreover, partial surface wettability for irradiated and non-irradiated ceramics. Irradiated surface demonstrated more rough surface in lithium disilicate than zirconia ceramics. CO 2 irradiation could increase shear bond strength, surface roughness and wettability for both CAD/CAM ceramics.

Expression of fas protein on CD4+T cells irradiated by low level He-Ne

NASA Astrophysics Data System (ADS)

Nie, Fan; Zhu, Jing; Zhang, Hui-Guo

2005-07-01

Objective: To investigate the influence on the Expression of Fas protein on CD4+ T cells irradiated by low level He-Ne laser in the cases of psoriasis. Methods:the expression of CD4+ T Fas protein was determined in the casee of psoriasis(n=5) pre and post-low level laser irradiation(30 min、60min and 120min)by flow cytometry as compared withthe control(n=5). Results:In the cases of psoriasis,the expression of CD4+T FAS protein 21.4+/-3.1% was increased significantly than that of control group 16.8+/-2.1% pre-irradiation, p<0.05in the control,there is no difference between pre and post- irradiation,p>0.05in the cases , the expression of CD4+T Fas protein wae positively corelated to the irradiation times, when the energy density arrived to 22.92J/cm2（60 minutes）and 45.84J/cm2（120minutes）, the expression of CD4+ T Fas protein was increased significantly as compared with pre-irradiation,p<0.05.Conclusion: The expression of CD4+T Fas protein may be increased by low level He-Ne laser irradiation ,the uncontrolled status of apoptosis could be corrected.

Influence of gamma irradiation on productivity indices of the edible Emperor moth caterpillar, Cirina forda (Lepidoptera: Saturniidae).

PubMed

Odeyemi, M O; Fasoranti, J O; Ande, A T; Olayemi, I K

2013-08-01

This study was aimed at generating baseline information for sustainable genetic improvement of Cirana forda larvae for entomophagy, through the use of gamma irradiation. Eggs of C. forda were irradiated with increasing doses of gamma rays from 0 to 200 Gy and raised through larval instal stages under laboratory conditions. The Body Weight (BW) and Head Capsule Width (HCW) of the larval instar stages were monitored as indices of productivity. Successful larval emergence was recorded for all irradiation doses tested and BW of the 1st and 2nd instar larvae were not significantly (p > 0.05) different between the control and treated groups (range = 0.021 +/- 0.003 g/larva in the 200 Gy treatment to 0.028 +/- 0.003 g/larva in the control group and 0.105 +/- 0.003 g/larva in 20 Gy treatment to 0.172 +/- 0.009 g/larva in the control group, respectively). On the other hand, BW during the 3rd and 4th larval instars were significantly (p < 0.05) lower among the irradiated treatments than control. Pattern of distribution of HCW was different from that of BW; as HCW increased with irradiation dose from 10-50 Gy during the 3rd and 4th larval instars. Also, HCW during the 5th instar larvae among the irradiated treatments (range = 5.256 +/- 0.012 to 5.662 +/- 0.026 mm) were not higher than that of the 6th instar in the control group (6.065 +/- 0.010 mm). These results suggest promising potentials of the use of gamma irradiation in sustainably improving the productivity of C. forda larvae for entomophagy.

Irradiated foods

MedlinePlus

... materials that kill bacteria. The process is called irradiation. It is used to remove germs from food. ... it reduces the risk for food poisoning . Food irradiation is used in many countries. It was first ...

Irradiation creep and stress-enhanced swelling of Fe-16Cr-15Ni-Nb austenitic stainless steel in BN-350

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vorobjev, A.N.; Porollo, S.I.; Konobeev, Yu.V.

1997-04-01

Irradiation creep and void swelling will be important damage processes for stainless steels when subjected to fusion neutron irradiation at elevated temperatures. The absence of an irradiation device with fusion-relevant neutron spectra requires that data on these processes be collected in surrogate devices such as fast reactors. This paper presents the response of an annealed austenitic steel when exposed to 60 dpa at 480{degrees}C and to 20 dpa at 520{degrees}C. This material was irradiated as thin-walled argon-pressurized tubes in the BN-350 reactor located in Kazakhstan. These tubes were irradiated at hoop stresses ranging from 0 to 200 MPa. After irradiationmore » both destructive and non-destructive examination was conducted.« less

Developments and potential of radiation processing in the Philippines

NASA Astrophysics Data System (ADS)

Singson, C.; Carmona, C.

This paper describes the research and development activities in three areas of radiation processing, namely: food irradiation, medical product sterilization and wood plastic combination. Plans and efforts exerted to acquire a larger gamma source to augment our present 5,000 curie source are discussed. Cost estimates for a radiation facility is presented on the basis of the market potential of food irradiation and medical product sterilization. Existing local industries that can benefit from the adaptation of irradiation technology in their processing requirements is described.

Design of continuous surface-relief phase plates by surface-based simulated annealing to achieve control of focal-plane irradiance

NASA Astrophysics Data System (ADS)

Lin, Y.; Kessler, T. J.; Lawrence, G. N.

1996-10-01

High-performance phase plates are of vital concern for controlling the far-field irradiance of laser-fusion systems. Several designs for solving this difficult problem have been reported in Optics Letters [e. g., S. N. Dixit et al., Opt. Lett. 19, 417 (1994)]. We report a surface-based form of simulated annealing that significantly improves the irradiance control while eliminating the high-scatter problems that have plagued other methods.

Association of Diet With Skin Histological Features in UV-B–Exposed Mice

PubMed Central

Hsia, Yvonne; Weeks, David M.; Dixon, Tatiana K.; Lepe, Jessica; Thomas, J. Regan

2017-01-01

Importance Long-term exposure to solar radiation produces deleterious photoaging of the skin. It is not known if diet can influence skin photoaging. Objectives To study the influence of a calorie-restricted diet and an obesity diet in mice exposed to long-term UV-B irradiation to assess if there is an association between diet and histopathological response to UV-B irradiation. Design, Setting, and Participants In this animal model study in an academic setting, the dorsal skin of SKH1 hairless mice receiving normal, calorie-restricted, and obesity diets was exposed to UV-B irradiation 3 times a week for 10 weeks and were compared with corresponding controls. The mice were placed in the following groups, with 8 animals in each group: (1) intact control (C) with regular diet and no UV-B exposure, (2) intact control with UV-B exposure (CR), (3) calorie-restricted diet (CrC), (4) calorie-restricted diet with UV-B exposure (CrR), (5) obesity diet (OC), and (6) obesity diet with UV-B exposure (OR). The experiment was conducted during October through December 2013. Tissue processing and histological analysis were completed in 2016. Main Outcomes and Measures Histomorphometric analysis was performed on paraffin-embedded skin sections stained by histological and immunohistochemical methods for estimation of epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, mast cells, dermal cellularity, and adipose layer ratio. Changes in wrinkles were noted. Results Hairless female mice (age range, 6-8 weeks) were obtained. With a normal diet, changes from UV-B irradiation occurred in epidermal thickness, epidermal proliferating cell nuclear antigen index, collagen I, elastic fibers, fibroblasts, and mast cells, which were modestly influenced by an obesity diet. Calorie restriction influenced the skin in nonirradiated control animals, with higher values for most variables. After UV-B exposure in animals with calorie restriction, epidermal thickness was increased, but other variables were unaffected. Animals receiving the calorie-restricted diet lost weight when exposed to long-term UV-B irradiation. Wrinkles were reduced in the calorie-restricted control group and in UV-B–exposed animals who received the obesity diet. Conclusions and Relevance Dietary alterations seem to modify histopathological responses to UV-B exposure in the skin of hairless mice. Level of Evidence NA. PMID:28418519

Electron irradiation of dry food products

NASA Astrophysics Data System (ADS)

Grünewald, Th.

The interest of the industrial food producer is increasing in having the irradiation facility installed in the food processing chain. The throughput of the irradiator should be high and the residence time of the product in the facility should be short. These conditions can be accomplished by electron irradiators. To clarify the irradiation conditions spices taken out of the industrial process, food grade salt, sugar, and gums as models of dry food products were irradiated. With a radiation dose of 10 kGy microbial load can be reduced on 10∗∗4 microorganisms/g. The sensory properties of the spices were not changed in an atypical way. For food grade salt and sugar changes of colour were observed which are due to lattice defects or initiated browning. The irradiation of several gums led only in some cases to an improvement of the thickness properties in the application below 50°C, in most cases the thickness effect was reduced. The products were packaged before irradiation. But it would be possible also to irradiate the products without packaging moving the product through the iradiation field in a closed conveyor system.

Facilities for studing radiation damage in nonmetals during irradiation

NASA Astrophysics Data System (ADS)

Levy, P. W.

1984-08-01

Two facilities were developed for making optical absorption, luminescence and other measurements on a single sample before, during and after irradiation. One facility uses Co-60 gamma rays and the other 0.5 to 3 MeV electrons from an accelerator. Optical relays function as spectrophotometers, luminescence detectors, etc. All radiation sensitive components are outside of walk-in irradiation chambers; all measurement control and data recording is computerized. Irradiations are made at controlled temperatures between 5 K and 900 C. The materials studied include glasses, quartz, alkali halides (especially natural rock salt), organic crystals, etc. As determined from color center measurements the damage formation rate in all materials studied at 25 C or above is strongly temperature dependent. The defect concentration during irradiation is usually much greater than that measured after irradiation. The fraction of defects annealing after irradiation and the annealing rate usually increases as the irradiation temperature increases. The completed studies demonstrate that, in most cases, the extent of maximum damage and the damage formation and annealing kinetics can be determined only by making measurements during irradiation.

THE EFFECT OF IRRADIATION OF THE BODY ON THE VIRULENCE OF TYPHOID FEVER BACILLI (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chekatilo, G.A.

1958-03-01

The study was carried out on the pathogenic properties of typhoid fever bacilli from the organism of irradiated (by 100, 200, and 300 r) and non- irradiated (control) guinea pigs. The animals were infected intracutaneously, after irradiation. The pathogenic properties of the microbes, isolated from the cutaneous foci, were examined by intraperitoneal inoculation of white mice with the dose of 15 and 30 million microbes. The total of 156 strains were examined and 762 mice were infected. lt was established that the mortality of mice infected with the bacterial cultures isolated from irradiated guinea pigs was higher than in micemore » infected with cultures isolated from non-irradiated mice (54.5% in the experimental group, as against 38% in the control group). Besides, it was revealed that the longer the microbes remained in the tissues of the macroorganism the greater became their virulence. This property was more pronounced in irradiated animals. Therefore, increase of the microbe virulence in the irradiated orgaaism is connected with the effect of irradiation which acts upon the microbes through the organism. (tr-auth)« less

21 CFR 179.21 - Sources of radiation used for inspection of food, for inspection of packaged food, and for...

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sources of radiation used for inspection of food, for inspection of packaged food, and for controlling food processing. 179.21 Section 179.21 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) IRRADIATION IN...

Economics of food irradiation

NASA Astrophysics Data System (ADS)

Kunstadt, Peter; Eng, P.; Steeves, Colyn; Beaulieu, Daniel; Eng, P.

1993-07-01

The number of products being radiation processed worldwide is constantly increasing and today includes such diverse items as medical disposables, fruits and vegetables, spices, meats, seafoods and waste products. This range of products to be processed has resulted in a wide range of irradiator designs and capital and operating cost requirements. This paper discusses the economics of low dose food irradiation applications and the effects of various parameters on unit processing costs. It provides a model for calculating specific unit processing costs by correlating known capital costs with annual operating costs and annual throughputs. It is intended to provide the reader with a general knowledge of how unit processing costs are derived.

Low Doses of Gamma-Irradiation Induce an Early Bystander Effect in Zebrafish Cells Which Is Sufficient to Radioprotect Cells

PubMed Central

Pereira, Sandrine; Malard, Véronique; Ravanat, Jean-Luc; Davin, Anne-Hélène; Armengaud, Jean; Foray, Nicolas; Adam-Guillermin, Christelle

2014-01-01

The term “bystander effect” is used to describe an effect in which cells that have not been exposed to radiation are affected by irradiated cells though various intracellular signaling mechanisms. In this study we analyzed the kinetics and mechanisms of bystander effect and radioadaptation in embryonic zebrafish cells (ZF4) exposed to chronic low dose of gamma rays. ZF4 cells were irradiated for 4 hours with total doses of gamma irradiation ranging from 0.01–0.1 Gy. In two experimental conditions, the transfer of irradiated cells or culture medium from irradiated cells results in the occurrence of DNA double strand breaks in non-irradiated cells (assessed by the number of γ-H2AX foci) that are repaired at 24 hours post-irradiation whatever the dose. At low total irradiation doses the bystander effect observed does not affect DNA repair mechanisms in targeted and bystander cells. An increase in global methylation of ZF4 cells was observed in irradiated cells and bystander cells compared to control cells. We observed that pre-irradiated cells which are then irradiated for a second time with the same doses contained significantly less γ-H2AX foci than in 24 h gamma-irradiated control cells. We also showed that bystander cells that have been in contact with the pre-irradiated cells and then irradiated alone present less γ-H2AX foci compared to the control cells. This radioadaptation effect is significantly more pronounced at the highest doses. To determine the factors involved in the early events of the bystander effect, we performed an extensive comparative proteomic study of the ZF4 secretomes upon irradiation. In the experimental conditions assayed here, we showed that the early events of bystander effect are probably not due to the secretion of specific proteins neither the oxidation of these secreted proteins. These results suggest that early bystander effect may be due probably to a combination of multiple factors. PMID:24667817

Radiosensitivity study and radiation effects on morphology characterization of grey oyster mushroom Pleurotus sajor-caju

NASA Astrophysics Data System (ADS)

Rashid, Rosnani Abdul; Daud, Fauzi; Senafi, Sahidan; Awang, Mat Rasol; Mohamad, Azhar; Mutaat, Hassan Hamdani; Maskom, Mohd Meswan

2014-09-01

Radiosensitive dosage and morphology characterization of irradiated grey oyster mushroom Pleurotus sajor-caju by gamma rays was investigated due to effects of irradiation. In order to establish the effect, mycelium of P. sajor-caju was irradiated by gamma rays at dose 0.1 to 8.0 kGy with dose rate 0.227 Gy sec-1. The irradiation of mycelia was carried out at the radiation facility in Malaysian Nuclear Agency. The radiosensitivity study was performed by evaluating the percentage of survival irradiated mycelia. The lethal dose of the mycelium P. sajor-caju was determined at 4.0 kGy and LD50 to be equal at 2.2 kGy. The radiation effects on morphology were evaluated based on growth rate of irradiated mycelia, mycelia types, colonization period on substrate, morphology of fruit bodies and yields. The results shown growth rate of irradiated mycelium was slightly lower than the control and decreased as the dose increased. Irradiation was found can induced the primordia formation on PDA and the BE of irradiated seed is higher than to control. The irradiation is proven to be useful for generating new varieties of mushroom with commercial value to the industry.

Chemiluminescence measurements on irradiated garlic powder by the single photon counting technique

NASA Astrophysics Data System (ADS)

Narvaiz, P.

1995-02-01

The feasibility of identifying irradiated garlic powder measuring chemiluminescence by liquid scintillation spectrometry was studied. Samples packed in 100 μm thick polyethylene bags were irradiated in a 60Co semi-industrial facility, with doses of 10 and 30 kGy. Control and irradiated samples were stored at 20 ± 4°C and 70 ± 10% RH in darkness for 2 years. Assays were performed to establish the best sample concentration and pH of the buffer solution in which garlic powder was to be suspended for its measurement. The water content of garlic samples was also analyzed throughout storage time, as it related to the stability of the species causing luminescence. Chemiluminescence values diminished in every sample over storage time following an exponential pattern. Irradiated samples showed values significantly higher than those of the control samples, according to the radiation dose, throughout the storage period. This does not necessarily imply that the identification of the irradiated samples would be certain, since values of control samples coming from different origins have been found to fluctuate within a rather wide range. Nonetheless, in principle, the method looks promising for the measurement of chemiluminescence in irradiated samples

Synergistic Effect of Freezing and Irradiation on Bonito Fish ( Sarda sarda Bloch, 1793).

PubMed

Altan, Can Okan; Turan, Hülya

2016-12-01

In this study, bonito fish ( Sarda sarda Bloch, 1793) were irradiated at 3 or 5 kGy, packaged, frozen, and stored at -20 ± 2°C for 12 months. During storage, the microbiological, physical, and chemical changes of the fish flesh were then assessed. Increasing the irradiation dose to 5 kGy provided greater inhibition of mesophilic and psychotropic aerobic bacteria (P < 0.05). Because fewer bacteria were detected in irradiated (3 and 5 kGy) as compared with unirradiated control fish suggests that freezing and irradiation yielded better results when combined. Irradiation at 3 and 5 kGy also positively impacted water activity, total volatile basic nitrogen, thiobarbituric acid-reactive substances, trimethylamine, and odor compared with the control group. However, a significant difference was not seen between the 3- and 5-kGy groups in terms of water activity, total volatile basic nitrogen, thiobarbituric acid-reactive substances, trimethylamine, and odor results (P > 0.05). Based on these findings, fish irradiated at 3 and 5 kGy remained within consumable limits during 12 months of frozen storage, while the control group was unacceptable after 9 months.

Neuropathological evaluation of monkeys exposed to body-alone X-radiation.

NASA Technical Reports Server (NTRS)

Haymaker, W.; Sturrock, D.; Kirk, J. H.; Casey, H. W.; Call, N. A.

1972-01-01

Investigation of the problem of whether morphological changes occurring in the central nervous system (CNS) following whole-body irradiation are attributable in part to abscopal factors. The 12 monkeys irradiated and the 6 that served as controls were chosen from a pool of 25 young monkeys. Over the postirradiation survival period of 14 days the hematocrit and hemoglobin values varied only slightly from the baseline values and from the values in the 6 control animals. White cell fractions were reduced in quantity but tended to recover relatively soon after irradiation. The design of this experiment was regarded as adequate to allow a conclusion whether pathological changes in the CNS of the irradiated animals differed from or exceeded those observed in the control animals. That such occurred on both counts in 3 of the 12 irradiated animals was evident. It appears that all the lesions must have been abscopally induced.

Effects of chemical, physical, and technological processes on the nature of food allergens.

PubMed

Poms, Roland E; Anklam, Elke

2004-01-01

A review is presented of studies of different processing techniques and their effect on the allergenicity and antigenicity of certain allergenic foods. An overview of investigated technologies is given with regard to their impact on the protein structure and their potential application in the production of hypoallergenic foods. The use of physical processes (such as heating, high pressure, microparticulation, ultrafiltration, and irradiation), chemical processes (such as proteolysis, fermentation, and refining by extraction), and biotechnological approaches, as well as the effects of these processes on individual allergenic foods, are included. Additionally, the implications of food processing for food allergen analysis with respect to food safety assessment and industrial quality control are briefly discussed.

Unraveling atomic-level self-organization at the plasma-material interface

NASA Astrophysics Data System (ADS)

Allain, J. P.; Shetty, A.

2017-07-01

The intrinsic dynamic interactions at the plasma-material interface and critical role of irradiation-driven mechanisms at the atomic scale during exposure to energetic particles require a priori the use of in situ surface characterization techniques. Characterization of ‘active’ surfaces during modification at atomic-scale levels is becoming more important as advances in processing modalities are limited by an understanding of the behavior of these surfaces under realistic environmental conditions. Self-organization from exposure to non-equilibrium and thermalized plasmas enable dramatic control of surface morphology, topography, composition, chemistry and structure yielding the ability to tune material properties with an unprecedented level of control. Deciphering self-organization mechanisms of nanoscale morphology (e.g. nanodots, ripples) and composition on a variety of materials including: compound semiconductors, semiconductors, ceramics, polymers and polycrystalline metals via low-energy ion-beam assisted plasma irradiation are critical to manipulate functionality in nanostructured systems. By operating at ultra-low energies near the damage threshold, irradiation-driven defect engineering can be optimized and surface-driven mechanisms controlled. Tunability of optical, electronic, magnetic and bioactive properties is realized by reaching metastable phases controlled by atomic-scale irradiation-driven mechanisms elucidated by novel in situ diagnosis coupled to atomistic-level computational tools. Emphasis will be made on tailored surface modification from plasma-enhanced environments on particle-surface interactions and their subsequent modification of hard and soft matter interfaces. In this review, we examine current trends towards in situ and in operando surface and sub-surface characterization to unravel atomic-scale mechanisms at the plasma-material interface. This work will emphasize on recent advances in the field of plasma and ion-induced nanopatterning and nanostructuring as well as ultra-thin film deposition. Future outlook will examine the critical role of complementary surface-sensitive techniques and trends towards advances in both in situ and in operando tooling.

Effects of irradiation source and dose level on quality characteristics of processed meat products

NASA Astrophysics Data System (ADS)

Ham, Youn-Kyung; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Kim, Yong-Jae; Choi, Yun-Sang; Song, Beom-Seok; Park, Jong-Heum; Kim, Cheon-Jei

2017-01-01

The effect of irradiation source (gamma-ray, electron-beam, and X-ray) and dose levels on the physicochemical, organoleptic and microbial properties of cooked beef patties and pork sausages was studied, during 10 days of storage at 30±1 °C. The processed meat products were irradiated at 0, 2.5, 5, 7.5, and 10 kGy by three different irradiation sources. The pH of cooked beef patties and pork sausages was unaffected by irradiation sources or their doses. The redness of beef patties linearly decreased with increasing dose level (P<0.05), obviously by e-beam irradiation compared to gamma-ray and X-ray (P<0.05). The redness of pork sausages was increased by gamma-ray irradiation, whereas it decreased by e-beam irradiation depending on absorbed dose level. No significant changes in overall acceptability were observed for pork sausages regardless of irradiation source (P>0.05), while gamma-ray irradiated beef patties showed significantly decreased overall acceptability in a dose-dependent manner (P<0.05). Lipid oxidation of samples was accelerated by irradiation depending on irradiation sources and dose levels during storage at 30 °C. E-beam reduced total aerobic bacteria of beef patties more effectively, while gamma-ray considerably decreased microbes in pork sausages as irradiation dose increased. The results of this study indicate that quality attributes of meat products, in particular color, lipid oxidation, and microbial properties are significantly influenced by the irradiation sources.

21 CFR 579.12 - Incorporation of regulations in part 179.

Code of Federal Regulations, 2014 CFR

2014-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IRRADIATION IN THE PRODUCTION, PROCESSING, AND HANDLING.... Regulations providing for irradiation in the production, processing, and handling of food in part 179 of this...

21 CFR 579.12 - Incorporation of regulations in part 179.

Code of Federal Regulations, 2012 CFR

2012-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IRRADIATION IN THE PRODUCTION, PROCESSING, AND HANDLING.... Regulations providing for irradiation in the production, processing, and handling of food in part 179 of this...

21 CFR 579.12 - Incorporation of regulations in part 179.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IRRADIATION IN THE PRODUCTION, PROCESSING, AND HANDLING.... Regulations providing for irradiation in the production, processing, and handling of food in part 179 of this...

21 CFR 579.12 - Incorporation of regulations in part 179.

Code of Federal Regulations, 2011 CFR

2011-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IRRADIATION IN THE PRODUCTION, PROCESSING, AND HANDLING.... Regulations providing for irradiation in the production, processing, and handling of food in part 179 of this...

21 CFR 579.12 - Incorporation of regulations in part 179.

Code of Federal Regulations, 2013 CFR

2013-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IRRADIATION IN THE PRODUCTION, PROCESSING, AND HANDLING.... Regulations providing for irradiation in the production, processing, and handling of food in part 179 of this...

21 CFR 179.25 - General provisions for food irradiation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false General provisions for food irradiation. 179.25... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.25 General provisions for food irradiation. For the purposes...

21 CFR 179.25 - General provisions for food irradiation.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false General provisions for food irradiation. 179.25... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.25 General provisions for food irradiation. For the purposes...

21 CFR 179.25 - General provisions for food irradiation.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false General provisions for food irradiation. 179.25... (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.25 General provisions for food irradiation. For the purposes of § 179.26, current good...

21 CFR 179.25 - General provisions for food irradiation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true General provisions for food irradiation. 179.25... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.25 General provisions for food irradiation. For the purposes...

21 CFR 179.25 - General provisions for food irradiation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false General provisions for food irradiation. 179.25... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.25 General provisions for food irradiation. For the purposes...

Target volume delineation for radical radiotherapy of early oesophageal carcinoma in elderly patients.

PubMed

Su, J; Zhu, S; Liu, Z; Zhao, Y; Song, C

2017-02-01

To compare the prognosis of elderly patients with early oesophageal carcinoma between radical elective nodal prophylactic irradiation and involved-field irradiation and to estimate the failure modes and adverse effects, then to provide the patients the safe and individual therapeutic regimens. The charts of 96 patients aged 65 and over with early stage oesophageal carcinoma receiving radical radiotherapy in our department were retrospectively analysed. Of all the patients, 49 received elective nodal prophylactic irradiation and the other 47 received involved-field irradiation. After completion of the whole treatment, we analysed short-term effects, tumour local control, overall survival of the patients, failure modes and adverse effects. The 1-, 3-, and 5-year local control rate in elective nodal irradiation and involved-field irradiation groups were 80.6%, 57.4%, 54.0% and 65.4%, 46.5%, 30.5% respectively, and the difference was statistically significant (χ 2 =4.478, P=0.03). The differences of overall survival and progression-free survival were not significant (P>0.05). The difference of 1-, 3-, and 5-years local regional failure rate was statistically significant between elective nodal prophylactic irradiation and involved-field irradiation groups, except for the overall failure and distant metastasis rates. The overall incidence of radiation-induced oesophagitis after elective nodal irradiation or involved-field irradiation was 79.6% and 59.6%, and the difference was statistically significant (χ 2 =4.559, P=0.03). The difference of radiation pneumonitis between elective nodal prophylactic irradiation and involved-field irradiation was not significant (12.2% vs 14.9%; χ 2 =0.144, P=0.7). For elderly patients with early stage oesophageal carcinoma receiving radical radiotherapy, although elective nodal prophylactic irradiation could increase the incidence of radiation-induced oesophagitis, patients could tolerate the treatment and benefit from local control. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Effect of pulmonary irradiation from inhaled /sup 90/Y on immunity to Listeria monocytogenes in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanchez, A.; Lundgren, D.L.; McClellan, R.O.

1976-01-01

The immunological response of mice subjected to irradiation from particles deposited in the lungs and challenged with Listeria monocytogenes was investigated. Mice, exposed by inhalation to /sup 90/Y (a beta-emitting radionuclide) in relatively insoluble fused aluminosilicate particles, were immunized with L. monocytogenes either before or after exposure. Two additional groups of mice were either immunized or irradiated only. A group of control mice received no irradiation or immunization. The beta radiation dose absorbed by the lungs of each mouse at time of challenge averaged 10,000 rads. Fourteen days after immunization, all mice were challenged with 2 LD/sub 50/ doses ofmore » L. monocytogenes via the respiratory route. Survival of all immunized mice either with or without exposure to /sup 90/Y varied from 90 to 100% as compared to 10 to 20% for the mice irradiated only and for control mice through 14 days after challenge. Pulmonary clearance of inhaled L. monocytogenes during the first 4 hr after challenge was suppressed in the mice irradiated only but not in those immunized only, or in the immunized and irradiated groups, and control mice. There appeared to be a suppression of proliferation of L. monocytogenes in lungs and spleen in the immunized groups 72 hr after challenge, whereas the lungs and spleens of the mice irradiated only and the control mice had extensive bacterial invasion. It was concluded that the 10,000 rads of beta radiation absorbed by the lungs did not suppress the immune mechanisms of the immunized mice.« less

The effectiveness of the microbiological radiation decontamination process of agricultural products with the use of low energy electron beam

NASA Astrophysics Data System (ADS)

Gryczka, Urszula; Migdał, Wojciech; Bułka, Sylwester

2018-02-01

The effectiveness of the radiation decontamination process was tested for electron beam of energy 200 keV and 300 keV. The energy of electrons was controlled by the measurements of its penetration ability in stack of B3 dosimetric film. In the presented work, the reduction of total aerobic bacteria count was observed, depending on time of irradiation for samples of dried black pepper, onion flakes and bay leaves. The results were compared with the effect observed for the process where high energy electron beam was used.

Laser synthesized super-hydrophobic conducting carbon with broccoli-type morphology as a counter-electrode for dye sensitized solar cells.

PubMed

Gokhale, Rohan; Agarkar, Shruti; Debgupta, Joyashish; Shinde, Deodatta; Lefez, Benoit; Banerjee, Abhik; Jog, Jyoti; More, Mahendra; Hannoyer, Beatrice; Ogale, Satishchandra

2012-11-07

A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode.

Neutron radiation effects on Fabry-Perot fiber optic sensors

NASA Astrophysics Data System (ADS)

Liu, Hanying; Talnagi, Joseph; Miller, Don W.

2003-07-01

Nuclear Power Plant operators and Generation IV plant designers are considering advanced data transmission and measurement systems to improve system economics and safety, while concurrently addressing the issue of obsolescence of instrumentation and control systems. Fiber optic sensors have advantages over traditional sensors such as immunity to electromagnetic interference or radio frequency interference, higher sensitivity and accuracy, smaller size and less weight, higher bandwidth and multiplexing capability. A Fabry-Perot fiber optic sensor utilizes a unique interferometric mechanism and data processing technique, and has potential applications in nuclear radiation environments. Three sensors with different gamma irradiation history were irradiated in a mixed neutron/gamma irradiation field, in which the total neutron fluence was 2.6×10 16 neutrons/cm 2 and the total gamma dose was 1.09 MGy. All of them experienced a temperature shift of about 34°F but responded linearly to temperature changes. An annealing phenomenon was observed as the environmental temperature increased, which reduced the offset by approximately 63%.

Research on the liquid coolant applied in the high repetition rate slab amplifier

NASA Astrophysics Data System (ADS)

Wang, Bingyan; Li, Yangshuai; Zhang, Panzheng; Wang, Li; Zhang, Yanli; Feng, Tao; Zhou, Qiong; Liu, Qiang; Li, Haiyuan; Zhang, Xu; Zhou, Shenlei; Ma, Weixin; Zhu, Jian; Zhu, Jianqiang

2018-03-01

High repetition rate slab amplifier (HRRSA) is extraordinarily indispensable for the future fusion power plant, ultra-short laser, laser weapon, and so on. Thermal controlling is the decisive factor for the repetition rate and the output energy of the slab amplifier. For larger clear aperture HRRSA, flash-lamp pumped slab amplifier based on neodymium phosphate glass (Nd:glass) is chosen with the liquid cooling. The liquid coolant circulates across the Nd:glass and takes off the thermal induced in the pumping process. A novel liquid coolant (Series A) whose refractive index is the same with Nd:glass is proposed to alleviate the wavefront distortion induced by thermal. The chemical stability of the liquid coolant under high energy flash-lamp irradiation with 200 shots and under the irradiation of a 1053nm laser with 19 hours and 37 hours are experimented. The results show that the chemical stability of the liquid coolant is stable under irradiation.

Pulsed-Laser Irradiation Space Weathering of a Carbonaceous Chondrite

NASA Astrophysics Data System (ADS)

Thompson, M. S.; Keller, L. P.; Christoffersen, R.; Loeffler, M. J.; Morris, R. V.; Graff, T. G.; Rahman, Z.

2017-07-01

We used pulsed laser irradiation of the Murchison meteorite to simulate space weathering processes in the laboratory. We analyzed changes in the spectral, chemical, and microstructural characteristics of the material after irradiation.

Micromachined microwave signal control device and method for making same

DOEpatents

Forman, Michael A [San Francisco, CA

2008-09-02

A method for fabricating a signal controller, e.g., a filter or a switch, for a coplanar waveguide during the LIGA fabrication process of the waveguide. Both patterns for the waveguide and patterns for the signal controllers are created on a mask. Radiation travels through the mask and reaches a photoresist layer on a substrate. The irradiated portions are removed and channels are formed on the substrate. A metal is filled into the channels to form the conductors of the waveguide and the signal controllers. Micromachined quasi-lumped elements are used alone or together as filters. The switch includes a comb drive, a spring, a metal plunger, and anchors.

Method for making a micromachined microwave signal control device

DOEpatents

Forman, Michael A [Mountain House, CA

2011-02-15

A method for fabricating a signal controller, e.g., a filter or a switch, for a coplanar waveguide during the LIGA fabrication process of the waveguide. Both patterns for the waveguide and patterns for the signal controllers are created on a mask. Radiation travels through the mask and reaches a photoresist layer on a substrate. The irradiated portions are removed and channels are formed on the substrate. A metal is filled into the channels to form the conductors of the waveguide and the signal controllers. Micromachined quasi-lumped elements are used alone or together as filters. The switch includes a comb drive, a spring, a metal plunger, and anchors.

Investigation on the Maximum Power Point in Solar Panel Characteristics Due to Irradiance Changes

NASA Astrophysics Data System (ADS)

Abdullah, M. A.; Fauziah Toha, Siti; Ahmad, Salmiah

2017-03-01

One of the disadvantages of the photovoltaic module as compared to other renewable resources is the dynamic characteristics of solar irradiance due to inconsistency weather condition and surrounding temperature. Commonly, a photovoltaic power generation systems consist of an embedded control system to maximize the power generation due to the inconsistency in irradiance. In order to improve the simplicity of the power optimization control, this paper present the characteristic of Maximum Power Point with various irradiance levels for Maximum Power Point Tracking (MPPT). The technique requires a set of data from photovoltaic simulation model to be extrapolated as a standard relationship between irradiance and maximum power. The result shows that the relationship between irradiance and maximum power can be represented by a simplified quadratic equation. The first section in your paper

Production of ochratoxin A by Aspergillus ochraceus NRRL-3174 before and after exposures to 60Co irradiation.

PubMed Central

Applegate, K L; Chipley, J R

1976-01-01

Spores from the toxigenic organism Aspergillus ochraceus NRRL-3174 were exposed to specific levels of gamma irradiation and then allowed to germinate on selected media. Increases in ochratoxin A production by irradiated, compared to non-irradiated, spores were observed after inoculation of spores onto a cracked red wheat or into a synthetic liquid medium. Variations in daily ochratoxin production were also observed for control and irradiated spore-derived cultures developing on both media, with maximum toxin production varying from 7 to 11 days of incubation. The most notable increases in ochratoxin A production occurred from cultures developing from spores having been irradiated with 10, 25, or 50 krad. Exposures to 400 or 600 krad resulted in complete inhibition of spore germination and, consequently, no ochratoxin production. Of the two substrates used, wheat and synthetic, the quantities of ochratoxin A produced were significantly lower in the synthetic media than on the natural substrate. Higher and more rapid toxin production occurred from spores having been irradiated with 10, 25, 50, and 100 krad than occurred from the non-irradiated control spores when grown on synthetic media. Cultures derived from spores having been exposed to 10, 25, 50, and 100 krad produced significantly higher levels of ochratoxin A after 8 days of incubation on natural substrate than did the controls. Analysis of variance revealed that substrate, length of incubation, as well as irradiation levels all affected the time required to produce maximum levels of ochratoxin A. PMID:938031

Microstructure evolution during helium irradiation and post-irradiation annealing in a nanostructured reduced activation steel

NASA Astrophysics Data System (ADS)

Liu, W. B.; Ji, Y. Z.; Tan, P. K.; Zhang, C.; He, C. H.; Yang, Z. G.

2016-10-01

Severe plastic deformation, intense single-beam He-ion irradiation and post-irradiation annealing were performed on a nanostructured reduced activation ferritic/martensitic (RAFM) steel to investigate the effect of grain boundaries (GBs) on its microstructure evolution during these processes. A surface layer with a depth-dependent nanocrystalline (NC) microstructure was prepared in the RAFM steel using surface mechanical attrition treatment (SMAT). Microstructure evolution after helium (He) irradiation (24.8 dpa) at room temperature and after post-irradiation annealing was investigated using Transmission Electron Microscopy (TEM). Experimental observation shows that GBs play an important role during both the irradiation and the post-irradiation annealing process. He bubbles are preferentially trapped at GBs/interfaces during irradiation and cavities with large sizes are also preferentially trapped at GBs/interfaces during post-irradiation annealing, but void denuded zones (VDZs) near GBs could not be unambiguously observed. Compared with cavities at GBs and within larger grains, cavities with smaller size and higher density are found in smaller grains. The average size of cavities increases rapidly with the increase of time during post-irradiation annealing at 823 K. Cavities with a large size are observed just after annealing for 5 min, although many of the cavities with small sizes also exist after annealing for 240 min. The potential mechanism of cavity growth behavior during post-irradiation annealing is also discussed.

In Situ analysis of CO2 laser irradiation on controlling progression of erosive lesions on dental enamel.

PubMed

Lepri, Taísa Penazzo; Scatolin, Renata Siqueira; Colucci, Vivian; De Alexandria, Adílis Kalina; Maia, Lucianne Cople; Turssi, Cecília Pedroso; Corona, Silmara Aparecida Milori

2014-08-01

The present study aimed to evaluate in situ the effect of CO2 laser irradiation to control the progression of enamel erosive lesions. Fifty-six slabs of bovine incisors enamel (5 × 3 × 2.5 mm(3) ) were divided in four distinct areas: (1) sound (reference area), (2) initial erosion, (3) treatment (irradiated or nonirradiated with CO2 laser), (4) final erosion (after in situ phase). The initial erosive challenge was performed with 1% citric acid (pH = 2.3), for 5 min, 2×/day, for 2 days. The slabs were divided in two groups according to surface treatment: irradiated with CO2 laser (λ = 10.6 µm; 0.5 W) and nonirradiate. After a 2-day lead-in period, 14 volunteers wore an intraoral palatal appliance containing two slabs (irradiated and nonirradiated), in two intraoral phases of 5 days each. Following a cross-over design during the first intraoral phase, half of the volunteers immersed the appliance in 100 mL of citric acid for 5 min, 3×/day, while other half of the volunteers used deionized water (control). The volunteers were crossed over in the second phase. Enamel wear was determined by an optical 3D profilometer. Three-way ANOVA for repeated measures revealed that there was no significant interaction between erosive challenge and CO2 laser irradiation (P = 0.419). Erosive challenge significantly increased enamel wear (P = 0.001), regardless whether or not CO2 laser irradiation was performed. There was no difference in enamel wear between specimens CO2 -laser irradiated and non-irradiated (P = 0.513). Under intraoral conditions, CO2 laser irradiation did not control the progression of erosive lesions in enamel caused by citric acid. © 2014 Wiley Periodicals, Inc.

Absolute cavity pyrgeometer

DOEpatents

Reda, Ibrahim

2013-10-29

Implementations of the present disclosure involve an apparatus and method to measure the long-wave irradiance of the atmosphere or long-wave source. The apparatus may involve a thermopile, a concentrator and temperature controller. The incoming long-wave irradiance may be reflected from the concentrator to a thermopile receiver located at the bottom of the concentrator to receive the reflected long-wave irradiance. In addition, the thermopile may be thermally connected to a temperature controller to control the device temperature. Through use of the apparatus, the long-wave irradiance of the atmosphere may be calculated from several measurements provided by the apparatus. In addition, the apparatus may provide an international standard of pyrgeometers' calibration that is traceable back to the International System of Units (SI) rather than to a blackbody atmospheric simulator.

Pulsed-Laser Irradiation Space Weathering Of A Carbonaceous Chondrite

NASA Technical Reports Server (NTRS)

Thompson, M. S.; Keller, L. P.; Christoffersen, R.; Loeffler, M. J.; Morris, R. V.; Graff, T. G.; Rahman, Z.

2017-01-01

Grains on the surfaces of airless bodies experience irradiation from solar energetic particles and melting, vaporization and recondensation processes associated with micrometeorite impacts. Collectively, these processes are known as space weathering and they affect the spectral properties, composition, and microstructure of material on the surfaces of airless bodies, e.g. Recent efforts have focused on space weathering of carbonaceous materials which will be critical for interpreting results from the OSIRIS-REx and Hayabusa2 missions targeting primitive, organic-rich asteroids. In addition to returned sample analyses, space weathering processes are quantified through laboratory experiments. For example, the short-duration thermal pulse from hypervelocity micrometeorite impacts have been simulated using pulsed-laser irradiation of target material e.g. Recent work however, has shown that pulsed-laser irradiation has variable effects on the spectral properties and microstructure of carbonaceous chondrite samples. Here we investigate the spectral characteristics of pulsed-laser irradiated CM2 carbonaceous chondrite, Murchison, including the vaporized component. We also report the chemical and structural characteristics of specific mineral phases within the meteorite as a result of pulsed-laser irradiation.

Conventional and advanced oxidation processes used in disinfection of treated urban wastewater.

PubMed

Rodríguez-Chueca, J; Ormad, M P; Mosteo, R; Sarasa, J; Ovelleiro, J L

2015-03-01

The purpose of the current study is to compare the inactivation of Escherichia coli in wastewater effluents using conventional treatments (chlorination) and advanced oxidation processes (AOPs) such as UV irradiation, hydrogen peroxide (H2O2)/solar irradiation, and photo-Fenton processes. In addition, an analysis of the operational costs of each treatment is carried out taking into account the optimal dosages of chemicals used. Total inactivation of bacteria (7.5 log) was achieved by means of chlorination and UV irradiation. However, bacterial regrowth was observed 6 hours after the completion of UV treatment, obtaining a disinfection value around 3 to 4 log. On the other hand, the combination H2O2/solar irradiation achieved a maximum inactivation of E. coli of 3.30 ± 0.35 log. The photo-Fenton reaction achieved a level of inactivation of 4.87 ± 0.10 log. The order of disinfection, taking into account the reagent/cost ratio of each treatment, is as follows: chlorination > UV irradiation > photo-Fenton > H2O2/sunlight irradiation.

Chemical composition, at consuming ripeness level of tomatoes irradiated at mature green and greenish yellow stages of maturity

NASA Astrophysics Data System (ADS)

Al-Wandawi, H. K.; Abdul-Rahman, M. H.; Al-Shaickley, K. A.

Tomatoes (Lycopersicon esculentum L.,var.Monte carlo) have been Y-irradiated (100-400Krad) and left to ripen to consuming ripeness. The results revealed that in fruits irradiated with 100,200 and 300 krad at mature-green, 48 hour after harvesting and at greenish yellow stages of maturity, 24 hours after harvesting, the levels of ascorbic acid were accounted to 62, 51, 27% and 84, 59, 34% of control samples respectively. In fruits irradiated with 200 krad at mature-green stage and 48 hours after harvesting and in fruits irradiated with 400 krad at greenish yellow stage and 48 hours after harvesting, the levels of lycopene were 279 and 246% of that of control samples; while the lowest levels of lycopene were in fruits irradiated with 400 krad and at mature-green and greenish yellow stages and 48 hours after harvesting where lycopene accounted to 11 and 24% respectively when compared to control samples . on the other hand, radiation had no significant effect on PH, titrable acidity and °Brix of tomatoes.

Gamma greenhouse: A chronic facility for crops improvement and agrobiotechnology

NASA Astrophysics Data System (ADS)

Azhar, M.; Ahsanulkhaliqin, A. W.

2014-02-01

Gamma irradiation is one of the most common procedures in plant mutagenesis and agrobiotechnology activities. The procedures consist of chronic and acute gamma radiation. Generally, 60Co and 137Cs are gamma radiation sources for radiation processing with relatively high energy (half-life 5.27 years for 60Co and 30.1 years for 137Cs). The energy associated with gamma radiation is high enough to break the molecular bonds and ionize atoms without affecting structure of the atomic nucleus (avoiding induction of radioactivity). The Gamma Green House (GGH) is the only chronic irradiation facility in Malaysia, located at Malaysian Nuclear Agency (Nuclear Malaysia). GGH is used for induction of mutation in plants and other biological samples at low dose radiation over period of time depending on the nature and sensitivity of the plant species. The GGH consist of circular green house with 30 meters radius, control room and irradiator with interlock system. The irradiator produces low dose gamma radiation derived from Caesium-137 radioactive source. The biological samples can be exposed to low dose radiation in days, weeks, months or years. The current irradiation rate for GGH is 2.67 Gy/hr at 1 meter from the source. Chronic gamma irradiation produces a wider mutation spectrum and useful for minimizing radiation damages towards obtaining new improved traits for research and commercial values. The prospect of the gamma greenhouse is its uses in research, educations and services on induced mutation techniques for the improvement of plant varieties and microbes. In generating awareness and attract users to the facility, Nuclear Malaysia provides wide range of irradiation services for plant species and mutagenesis consultancies to academicians, students scientists, and plant breeders, from local universities, other research institutes, and growers. Charges for irradiation and consultancy services are at nominal rates. The utilization activities of the gamma greenhouse mainly cover Research and Development, Research Collaboration, Exchange of Information, Irradiation Services, Training Programs, Education, Exchange of Scientists and Seminars/ Conferences.

Emerging materials for solar cell applications: Electrodeposited CdTe

NASA Astrophysics Data System (ADS)

Rod, R. L.; Basol, B. M.; Stafsudd, O.

1980-09-01

Work was centered about improving electroplating processes and cell fabrication techniques, with emphasis being given to three differing n-CdTe/Au Schottky configurations. The highest values of efficiency related parameters achieved with a simulated solar irradiation of 100 mW/sq cm were 0.57V for open circuit voltage, 0.6 for fill factor, and 6 mA/sq cm for short circuit current. Four important parameters are known to control the quality of the Monosolar electrodeposition process and resultant solar cells. They are electrolyte temperature, Te concentration in the solution at a specific pH, deposition or quasi-rest potential, and flow pattern of the electrolyte (stirring). The first three considerations are believed to be fully understood and optimized. Work is underway to further understand the effects of stirring on the diffusion of ionic components and the effects on CdTe film performance. Work was accelerated during the quarter to increase the short circuit current. Parallel programs using laser irradiation of finished CdTe films, heat treatment, and changes in the electrodeposition process itself to recrystallize films were started.

High-energy proton irradiation of C57Bl6 mice under hindlimb unloading

NASA Astrophysics Data System (ADS)

Mendonca, Marc; Todd, Paul; Orschell, Christie; Chin-Sinex, Helen; Farr, Jonathan; Klein, Susan; Sokol, Paul

2012-07-01

Solar proton events (SPEs) pose substantial risk for crewmembers on deep space missions. It has been shown that low gravity and ionizing radiation both produce transient anemia and immunodeficiencies. We utilized the C57Bl/6 based hindlimb suspension model to investigate the consequences of hindlimb-unloading induced immune suppression on the sensitivity to whole body irradiation with modulated 208 MeV protons. Eight-week old C57Bl/6 female mice were conditioned by hindlimb-unloading. Serial CBC and hematocrit assays by HEMAVET were accumulated for the hindlimb-unloaded mice and parallel control animals subjected to identical conditions without unloading. One week of hindlimb-unloading resulted in a persistent, statistically significant 10% reduction in RBC count and a persistent, statistically significant 35% drop in lymphocyte count. This inhibition is consistent with published observations of low Earth orbit flown mice and with crewmember blood analyses. In our experiments the cell count suppression was sustained for the entire six-week period of observation and persisted for at least 7 days beyond the period of active hindlimb-unloading. C57Bl/6 mice were also irradiated with 208 MeV Spread Out Bragg Peak (SOBP) protons at the Midwest Proton Radiotherapy Institute at the Indiana University Cyclotron Facility. We found that at 8.5 Gy hindlimb-unloaded mice were significantly more radiation sensitive with 35 lethalities out of 51 mice versus 15 out of 45 control (non-suspended) mice within 30 days of receiving 8.5 Gy of SOBP protons (p =0.001). Both control and hindlimb-unloaded stocktickerCBC analyses of 8.5 Gy proton irradiated and control mice by HEMAVET demonstrated severe reductions in WBC counts (Lymphocytes and PMNs) by day 2 post-irradiation, followed a week to ten days later by reductions in platelets, and then reductions in RBCs about 2 weeks post-irradiation. Recovery of all blood components commenced by three weeks post-irradiation. CBC analyses of 8.5 Gy proton irradiated hindlimb-unloaded mice indicated that the recovery of the WBC counts appeared delayed compared to 8.5 Gy irradiated controls. However, stocktickerRBC recovery appeared similar in both sets of irradiated mice. Our data indicate that hindlimb-unloaded mice are more radiation sensitive compared to irradiated controls. We thank Brian Allen and Rick Jessup for valuable assistance with dosimetry and physical arrangements at the IU Cyclotron Facility and Midwest Proton Radiotherapy Institute and Alan Constance for design of hindlimb-unloading cages. Research supported in part by NASA Grant NNJ06HE95A.

Photoresponsive lipid-polymer hybrid nanoparticles for controlled doxorubicin release

NASA Astrophysics Data System (ADS)

Yao, Cuiping; Wu, Ming; Zhang, Cecheng; Lin, Xinyi; Wei, Zuwu; Zheng, Youshi; Zhang, Da; Zhang, Zhenxi; Liu, Xiaolong

2017-06-01

Currently, photoresponsive nanomaterials are particularly attractive due to their spatial and temporal controlled drug release abilities. In this work, we report a photoresponsive lipid-polymer hybrid nanoparticle for remote controlled delivery of anticancer drugs. This hybrid nanoparticle comprises three distinct functional components: (i) a poly(D,L-lactide-co-glycolide) (PLGA) core to encapsulate doxorubicin; (ii) a soybean lecithin monolayer at the interface of the core and shell to act as a molecular fence to prevent drug leakage; (iii) a photoresponsive polymeric shell with anti-biofouling properties to enhance nanoparticle stability, which could be detached from the nanoparticle to trigger the drug release via a decrease in the nanoparticle’s stability under light irradiation. In vitro results revealed that this core-shell nanoparticle had excellent light-controlled drug release behavior (76% release with light irradiation versus 10% release without light irradiation). The confocal microscopy and flow cytometry results also further demonstrated the light-controlled drug release behavior inside the cancer cells. Furthermore, a CCK8 assay demonstrated that light irradiation could significantly improve the efficiency of killing cancer cells. Meanwhile, whole-animal fluorescence imaging of a tumor-bearing mouse also confirmed that light irradiation could trigger drug release in vivo. Taken together, our data suggested that a hybrid nanoparticle could be a novel light controlled drug delivery system for cancer therapy.

[Protective Effect of S-isopentenyl-L-cysteine against DNA Damage in Irradiated Mice].

PubMed

Zheng, Qi-sheng; Yu, Guang-yun; He, Xin; Jiang, Ming; Chu, Xiao-fei; Zhao, Shu-yi; Fan, Sai-jun; Liu, Pei-xun

2015-10-01

To evaluate the protective effect of S-isopentenyl-L-cysteine,a new cysteine derivative,on DNA damage induced by radiation by using acute radiation injury animal models. Forty ICR mice were randomly divided into five groups:the control group,1.0Gy gamma irradiation group,1.0Gy gamma irradiation combined with S-isopentenyl-L-cysteine group,7.2Gy gamma irradiation group,and 7.2Gy gamma irradiation combined with S-isopentenyl-L-cysteine group,with 8 mice in each group.The comet assay and bone marrow polychromatic micronucleus experiments were performed to evaluate the double-strand DNA breaks in ICR mice exposed to 1.0 and 7.2Gy gamma-ray, respectively. The tail DNA percentage,tail length,tail moment,and olive tail moment of peripheral blood lymphocytes in 7.2Gy gamma irradiation group were significantly higher than that of the control group (P<0.01).And it was also observed that above experimental indexes of 7.2Gy gamma irradiation combined with S-isopentenyl-L-cysteine group was significantly less than that of 7.2Gy gamma irradiation group (P<0.05). In addition,the micronucleus rate of 1.0Gy gamma irradiation group and 7.2Gy gamma irradiation group were both significantly higher than in the control group (P<0.01). In addition,in mice given S-isopentenyl-L-cysteine before irradiation,the micronucleus rate of ICR mice exposed to 1.0 and 7.2Gy gamma-ray decreased from (39.5000 ± 3.3141)‰ to (28.1667±4.1345)‰ (P=0.033) and from (76.5000 ± 4.6242)‰ to (22.8333 ± 3.6553)‰(P=0.000),respectively. The bone marrow polychromatic micronucleus experiment indicated that the value of polychromatic erythrocyte (PCE)/normochromatic erythrocyte(NCE) of ICR mice exposed to 1.0 and 7.2Gy gamma-ray was less than the control group(P<0.05). Meanwhile,after irradiating by certain dose,the value of PCE/NCE in mice given S-isopentenyl-L-cysteine before irradiation was significantly higher than the corresponding groups (P<0.05). S-isopentenyl-L-cysteine has a good protective effect against DNA damage induced by radiation.

Nucleosynthetic Heterogeneity Controls Vanadium Isotope Variations in Bulk Chondrites

NASA Technical Reports Server (NTRS)

Nielsen, S. G.; Righter, K.; Wu, F.; Owens, J. D.; Prytulak, J.; Burton, K.; Parkinson, I.; Davis, D.

2018-01-01

The vanadium (V) isotope composition of early solar system materials have been hypothesized to be sensitive to high energy irradiation that originated from the young Sun. Vanadium has two isotopes with masses 50 and 51 that have (51)V/(50)V ratio of approximately 410. High energy irradiation produces (50)V from various target isotopes of Ti, Cr and Fe, which would result in light V isotope compositions (expressed as delta (51)V in per mille = 1000 x (((51)V/(50)V(sub sample)/(51)V/(50)V(sub AlfaAesar)) - 1)) relative to a presumably chondritic starting composition. Recently published V isotope data for calcium aluminium inclusions (CAIs) has revealed some very negative values relative to chondrites (by almost -4 per mille) that were indeed interpreted to reflect irradiation processes despite the fact that the studied CAIs all exhibited significant initial abundances of (10)Be, while only a few CAIs displayed light V isotope compositions. It is difficult to relate V isotope variations directly to a singular process because V only possesses two isotopes. Therefore, V isotope variations can principally be produced both mass dependent and independent processes. Mass dependent kinetic stable isotope fractionation is common in CAIs for refractory elements due to partial condensation/evaporation processes. The element strontium (Sr) has an almost identical condensation temperature to V and studies of stable Sr isotope compositions in CAIs reveal both heavy and light values relative to chondrites of several permil. These variations are similar in magnitude to those reported for V isotopes in CAIs, which suggests it is possible that some of the V isotope variation in CAIs could be due to kinetic stable isotope fractionation during condensation/evaporation processes.

Laboratory evaluation on a potential birth control diet for fruit fly sterile insect technique (SIT).

PubMed

Chang, Chiou Ling

2017-08-01

Sterile insect technique (SIT) is one of the most effective fruit fly control technologies. Irradiation has been used to sterilize male fruit flies before release to the field to compete with the wild males for females. Imagine an environmental and cost effective method using a rearing diet that can make insects sterile indefinitely, by feeding for 7days before release. This could replace costly irradiation process. A potential birth control diet was evaluated on fertility, mating, survival, and protein analysis for fruit fly species in Hawaii. Insects were continuously fed an agar diet with lufenuron (LFN) for 7d after emergence and then switched to a control diet to simulate the actual field condition. The influence on egg hatch was dose dependent. With dose of 2-4mg/g in the diet, egg hatch from LFN-fed was almost 100% suppressed for 24 experimental days if adults of Ceratitia capitate (Widemann), Bactrocera dorsalis (Hendel), and B. latifrons (Hendel) continued to feed on LFN diet. B. cucurbitae (Coquillett) was not affected by LFN. However, egg hatch from LFN fed B. latifrons and B. dorsalis were suppressed for at least 2weeks after switching to the control diet at 7d. Egg hatch did not recover >4% up to 24d. Proteome analysis revealed that ABD-4 protein was under expressed by 70-83% on LFN fed females and males of B. latifrons and B. dorsalis while Pbprp2 protein was significantly over expressed by 6-12 fold on LFN fed males only. These two proteins were not expressed in C. capitata and B. cucurbitae. Therefore, this report focused more on B. latifrons and B. dorsalis. This finding suggested a great potential for one alternative to sterilize fruit flies for SIT without irradiation. Published by Elsevier Inc.

Effect of radiation processing on meat tenderisation

NASA Astrophysics Data System (ADS)

Kanatt, Sweetie R.; Chawla, S. P.; Sharma, Arun

2015-06-01

The effect of radiation processing (0, 2.5, 5 and 10 kGy) on the tenderness of three types of popularly consumed meat in India namely chicken, lamb and buffalo was investigated. In irradiated meat samples dose dependant reduction in water holding capacity, cooking yield and shear force was observed. Reduction in shear force upon radiation processing was more pronounced in buffalo meat. Protein and collagen solubility as well as TCA soluble protein content increased on irradiation. Radiation processing of meat samples resulted in some change in colour of meat. Results suggested that irradiation leads to dose dependant tenderization of meat. Radiation processing of meat at a dose of 2.5 kGy improved its texture and had acceptable odour.

An experimental investigation of wastewater treatment using electron beam irradiation

NASA Astrophysics Data System (ADS)

Emami-Meibodi, M.; Parsaeian, M. R.; Amraei, R.; Banaei, M.; Anvari, F.; Tahami, S. M. R.; Vakhshoor, B.; Mehdizadeh, A.; Fallah Nejad, N.; Shirmardi, S. P.; Mostafavi, S. J.; Mousavi, S. M. J.

2016-08-01

Electron beam (EB) is used for disinfection and treatment of different types of sewage and industrial wastewater. However, high capital investment required and the abundant energy consumed by this process raise doubts about its cost-effectiveness. In this paper, different wastewaters, including two textile sewages and one municipal wastewater are experimentally studied under different irradiation strategies (i.e. batch, 60 l/min and 1000 m3/day) in order to establish the reliability and the optimum conditions for the treatment process. According to the results, EB improves the efficiency of traditional wastewater treatment methods, but, for textile samples, coagulation before EB irradiation is recommended. The cost estimation of EB treatment compared to conventional methods shows that EB has been more expensive than chlorination and less expensive than activated sludge. Therefore, EB irradiation is advisable if and only if conventional methods of textile wastewater treatment are insufficient or chlorination of municipal wastewater is not allowed for health reasons. Nevertheless, among the advanced oxidation processes (AOP), EB irradiation process may be the most suitable one in industrial scale operations.

X-ray-induced changes in growth of Mozambique tilapia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jana, B.B.; Basu, M.

1995-01-01

Early fry (30 d postfertilization) and 7-8-week-old Mozambique tilapias (Tilapia mossambica) were exposed to X rays in dosages of 50, 100, 200, 300, 400 or 500 roentgens and reared in outdoor culture tanks between May 1981 and October 1988. Fish of either sex that were irradiated as fry grew faster than controls at all test X-ray doses. Among fish irradiated at 7-8 weeks, males grew significantly faster, but females grew significantly slower, than controls at all test doses. X-ray-induced changes in growth were dose-dependent: growth rates of fry (both sexes) and of juvenile males rose relative to those of controlsmore » with increased radiation dose. The growth increase per unit of radiation dose was higher for fry than for older juveniles. The length-weight regression was steeper for irradiated males than for controls. The average weights of F{sub 1} offspring of irradiated fish were greatly reduced as compared with controls, which suggests the transfer of the detrimental effects of X rays from irradiated parents to their offspring. 39 refs., 3 figs., 3 tabs.« less

Marketing of irradiated commodities in South Africa

NASA Astrophysics Data System (ADS)

Du Plessis, TA; Stevens, RCB

Although the industrial exploitation of radiation processing in the medical and allied fields has been successfully marketed and applied for the past two decades in South Africa, the introduction of food radurisation on an industrial level adds a completely new dimension to the marketing of this processing technique. Extensive research into the use of radiation for the treatment of various foodstuffs has been carried out by the Nuclear Development Corporation of South Africa for more than a decade, resulting in South Africa being one of the first countries where a commercial irradiator dedicated to this branch of radiation processing, was established. The marketing of this process is especially difficult due to the emotive aspects associated with radiation and man's sensitive reaction to anything pertaining to his food. This situation was made even more difficult by the general public's apprehension towards nuclear activities throughout the world. In an attempt to transform the unfavourable public image associated with this process, an important first step was to form a National Steering Committee for the Marketing of Radurised Food, the members of which were drawn from various agricultural controlling bodies, the Department of Health, and other controlling bodies held in high esteem by the public, such as the Consumer Council and representatives from commerce and industry. This approach proved to be very successful and greatly assisted in creating a climate whereby the public in South Africa today generally has a favourable attitude towards the radurisation of foodstuffs. The development of this marketing strategy for food radurisation in South Africa is discussed in detail.

Radiation-induced degradation of cyclohexanebutyric acid in aqueous solutions by gamma ray irradiation

NASA Astrophysics Data System (ADS)

Jia, Wenbao; He, Yanquan; Ling, Yongsheng; Hei, Daqian; Shan, Qing; Zhang, Yan; Li, Jiatong

2015-04-01

The radiation-induced degradation of cyclohexanebutyric acid under gamma ray irradiation was investigated. Degradation experiments were performed with 100 mL sealed Pyrex glass vessels loaded with 80 mL of cyclohexanebutyric acid solutions at various initial concentrations of 10, 20, and 40 mg L-1. The absorbed doses were controlled at 0, 0.65, 1.95, 3.25, 6.5, 9.75, and 13 kGy. The results showed that gamma ray irradiation could effectively degrade cyclohexanebutyric acid in aqueous solutions. The removal rate of cyclohexanebutyric acid increased significantly with the increase of absorbed dose and the decrease of its initial concentration. At the same time, the removal of chemical oxygen demand (COD) was as effective as that of cyclohexanebutyric acid. The kinetic studies showed that the degradation of cyclohexanebutyric acid followed pseudo first-order reaction. Above all, the proposed mechanism obtained when NaNO2, NaNO3 and tert-butanol were added showed that the •OH radical played a major role in the gamma degradation process of cyclohexanebutyric acid, while •H and eaq- played a minor role in the gamma degradation process. The degradation products were identified by Fourier transform infrared spectroscopy (FTIR) and gas chromatography/mass spectrometry (GC/MS) during cyclohexanebutyric acid degradation.

Induction of Cell Death through Alteration of Oxidants and Antioxidants in Epithelial Cells Exposed to High Energy Protons

NASA Technical Reports Server (NTRS)

Ramesh, Govindarajan; Wu, Honglu

2012-01-01

Radiation affects several cellular and molecular processes including double strand breakage, modifications of sugar moieties and bases. In outer space, protons are the primary radiation source which poses a range of potential health risks to astronauts. On the other hand, the use of proton radiation for tumor radiation therapy is increasing as it largely spares healthy tissues while killing tumor tissues. Although radiation related research has been conducted extensively, the molecular toxicology and cellular mechanisms affected by proton radiation remain poorly understood. Therefore, in the present study, we irradiated rat epithelial cells (LE) with different doses of protons and investigated their effects on cell proliferation and cell death. Our data showed an inhibition of cell proliferation in proton irradiated cells with a significant dose dependent activation and repression of reactive oxygen species (ROS) and antioxidants, glutathione and superoxide dismutase respectively as compared to control cells. In addition, apoptotic related genes such as caspase-3 and -8 activities were induced in a dose dependent manner with corresponding increased levels of DNA fragmentation in proton irradiated cells than control cells. Together, our results show that proton radiation alters oxidant and antioxidant levels in the cells to activate apoptotic pathway for cell death.

Design of continuous surface-relief phase plates by surface-based simulated annealing to achieve control of focal-plane irradiance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Y.; Kessler, T.J.; Lawrence, G.N.

1996-10-01

High-performance phase plates are of vital concern for controlling the far-field irradiance of laser-fusion systems. Several designs for solving this difficult problem have been reported in {ital Optics} {ital Letters} [e.g., S. N. Dixit {ital et} {ital al}., Opt. Lett. {bold 19}, 417 (1994)]. We report a surface-based form of simulated annealing that significantly improves the irradiance control while eliminating the high-scatter problems that have plagued other methods. {copyright} {ital 1996 Optical Society of America.}

Irradiation of amelanotic melanoma cells with 532 nm high peak power pulsed laser radiation in the presence of the photothermal sensitizer Cu(II)-hematoporphyrin: a new approach to cell photoinactivation.

PubMed

Soncin, M; Busetti, A; Fusi, F; Jori, G; Rodgers, M A

1999-06-01

Cu(II)-hematoporphyrin (CuHp) was efficiently accumulated by B78H1 amelanotic melanoma cells upon incubation with porphyrin concentrations up to 52 microM. When the cells incubated for 18 h with 13 microM CuHp were irradiated with 532 nm light from a Q-switched Nd: YAG laser operated in a pulsed mode (10 ns pulses, 10 Hz) a significant decrease in cell survival was observed. The cell photoinactivation was not the consequence of a photodynamic process, as CuHp gave no detectable triplet signal upon laser flash photolysis excitation and no decrease in cell survival was observed upon continuous wave irradiation. Thus, it is likely that CuHp sensitization takes place by photothermal pathways. The efficiency of the photoprocess was modulated by different parameters; thus, while varying the amount of added CuHp in the 3.25-26 microM range had little effect, pulse energies larger than 50 mJ and irradiation times of at least 120 s were necessary to induce a cell inactivation of about 50%. The porphyrin-cell incubation time prior to irradiation had a major influence on cell survival, suggesting that the nature of the CuHp microenvironment can control the efficiency of photothermal sensitization.

Formation of TiO2 nanorings due to rapid thermal annealing of swift heavy ion irradiated films.

PubMed

Thakurdesai, Madhavi; Sulania, I; Narsale, A M; Kanjilal, D; Bhattacharyya, Varsha

2008-09-01

Amorphous thin films of TiO2 deposited by Pulsed Laser Deposition (PLD) method are irradiated by Swift Heavy Ion (SHI) beam. The irradiated films are subsequently annealed by Rapid Thermal Annealing (RTA) method. Atomic Force Microscopy (AFM) study reveals formation of nano-rings on the surface after RTA processing. Phase change is identified by Glancing Angle X-ray Diffraction (GAXRD) and Raman spectroscopy. Optical characterisation is carried out by UV-VIS absorption spectroscopy. Though no shift of absorption edge is observed after irradiation, RTA processing does show redshift.

21 CFR 179.45 - Packaging materials for use during the irradiation of prepackaged foods.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Packaging materials for use during the irradiation... OF HEALTH AND HUMAN SERVICES (CONTINUED) IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF... irradiation of prepackaged foods. The packaging materials identified in this section may be safely subjected...

7 CFR 319.74-2 - Conditions governing the entry of cut flowers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... eliminated. (e) Irradiation. Cut flowers and foliage that are required under this part to be treated or subjected to inspection to control one or more of the plant pests for which irradiation is an approved treatment under part 305 of this chapter may instead be treated with irradiation. Irradiation treatment must...

7 CFR 319.74-2 - Conditions governing the entry of cut flowers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... eliminated. (e) Irradiation. Cut flowers and foliage that are required under this part to be treated or subjected to inspection to control one or more of the plant pests for which irradiation is an approved treatment under part 305 of this chapter may instead be treated with irradiation. Irradiation treatment must...

7 CFR 319.74-2 - Conditions governing the entry of cut flowers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... eliminated. (e) Irradiation. Cut flowers and foliage that are required under this part to be treated or subjected to inspection to control one or more of the plant pests for which irradiation is an approved treatment under part 305 of this chapter may instead be treated with irradiation. Irradiation treatment must...

7 CFR 319.74-2 - Conditions governing the entry of cut flowers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... eliminated. (e) Irradiation. Cut flowers and foliage that are required under this part to be treated or subjected to inspection to control one or more of the plant pests for which irradiation is an approved treatment under part 305 of this chapter may instead be treated with irradiation. Irradiation treatment must...

Effect of gamma-ray irradiation on the device process-induced defects in 4H-SiC epilayers

NASA Astrophysics Data System (ADS)

Miyazaki, T.; Makino, T.; Takeyama, A.; Onoda, S.; Ohshima, T.; Tanaka, Y.; Kandori, M.; Yoshie, T.; Hijikata, Y.

2016-11-01

We investigated the gamma-ray irradiation effect on 4H-SiC device process-induced defects by photoluminescence (PL) imaging and deep level transient spectroscopy (DLTS). We found that basal plane dislocations (BPDs) that were present before the irradiation were eliminated by gamma-ray irradiation of 1 MGy. The reduction mechanism of BPD was discussed in terms of BPD-threading edge dislocation (TED) transformation and shrinkage of stacking faults. In addition, the entire PL image was gradually darkened with increasing absorbed dose, which is presumably due to the point defects generated by gamma-ray irradiation. We obtained DLTS peaks that could be assigned to complex defects, termed RD series, and found that the peaks increased with absorbed dose.

The nature of compensatory and restorative processes in the livers of animals irradiated during hypokinesia

NASA Technical Reports Server (NTRS)

Chernov, I. P.; Trusova, L. V.

1981-01-01

The nature of postirradiation repair in the livers of rats irradiated during hypokinesia is investigated. Hepatocyte population counts, mitotic activity, binuclear cell content, and karyometric studies were done to ascertain the effects of combined hypokinesia and radiation. Hypokinesia is shown to change the nature and rate of post-irradiation changes in the liver, the effect varying with the timing of irradiation relative to the length of hypokinesia. It is concluded that the changes in the compensatory and restorative processes are caused by stress developed in response to isolation and restricted mobility. By changing neuroendocrine system activity, the stress stimulates cell and tissue repair mechanisms at a certain stage essential to the body's reaction of subsequent irradiation.

Microbial pathogens in raw pork, chicken, and beef: benefit estimates for control using irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roberts, T.

1985-12-01

Various control procedures have been suggested for reducing foodborne infectious diseases. Receiving considerable attention is irradiation. This report estimates the medical and wage (or productivity) benefits associated with prevention of five human diseases transmitted by beef, pork, and chicken. (These diseases can also be transmitted by other vectors, such as eggs, milk, and pets. But these sources are not included in the analysis.) All of these foodborne infectious diseases - salmonellosis, campylobacteriosis, trichinosis, tapeworm, and toxoplasmosis - could be significantly reduced by irradiating meat and poultry. The Food and Drug Administration (FDA) has just approved irradiation of pork to preventmore » trichinosis (50FR 29658-59) and is considering approval of irradiation of chicken to kill Salmonella. 22 references.« less

GENETIC EFFECTS OF X IRRADIATION OF 10, 15, AND 20 GENERATIONS OF MALE MICE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spalding, J.F.; Brooks, M.R.; Archuleta, R.F.

1963-01-01

Male mice were exposed to 200 rads of x rays (acute whole body exposures) for 20 consecutive generations. Comparative studies were done on breeding characteristics of offspring from 10 and 15 generations of irradinted males. Irradiated line mice were less efficient breeders than were control line mice, and the decrement increased with the number of generations irradiated. Female mice from 10 to 20 generations of irradiated males were studied for resistance to low intensity gamma -rays and were found to be less resistant than control line mice. It was concluded that x irradiation to consecutive generations of male mice producesmore » a genetic decrement affecting both breeding and efficiency and stamina. (auth)« less

Cherry Irradiation Studies. 1984 annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eakin, D.E.; Hungate, F.P.; Tingey, G.L.

1985-04-01

Fresh cherries, cherry fruit fly larvae, and codling moth larvae were irradiated using the PNL cobalt-60 facility to determine the efficacy of irradiation treatment for insect disinfestation and potential shelf life extension. Irradiation is an effective disinfestation treatment with no significant degradation of fruit at doses well above those required for quarantine treatment. Sufficient codling moth control was achieved at projected doses of less than 25 krad; cherry fruit fly control, at projected doses of less than 15 krad. Dose levels up to 60 krad did not adversely affect cherry quality factors tested. Irradiation above 60 krad reduced the firmnessmore » of cherries but had no significant impact on other quality factors tested. Irradiation of cherries below 80 krad did not result in any significant differences in sensory evaluations (appearance, flavor, and firmness) in tests conducted at OSU. Irradiation up to 200 krad at a temperature of about 25/sup 0/C (77/sup 0/F) did not measurably extend shelf life. Irradiation at 500 krad at 25/sup 0/C (77/sup 0/F) increased mold and rotting of cherries tested. There is no apparent advantage of irradiation over low-temperature fumigation.« less

THE EFFECT OF IRRADIATION ON REPRODUCTION BY THE HETEROGENETIC GENERATION OF STRONGYLOIDES PAPILLOSUS. I. IRRADIATION OF MALES AND FEMALES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katz, F.F.

1960-06-01

Fourth and fifth stage male and third and fourth stage female S. papillosus were subjected to various doses of Co/sup 60/ gamma irradiation and cultured in vitro with controls of the opposite sex. Fewer offspring were produced in cultures containing irradiated males than in cultures of irradiated females. A single experiment involving several doses and one control gave a more linear picture of the effects of irradiation than individual experiments carried out at various times for different dose levels. In the former, larvae were obtained in cultures of nematodes exposed to 20 kr but not to 40, 60, 80 ormore » 100 kr; in the latter, larvae occurred in cultures of males irradiated at 42 kr and in cultures of females exposed to 50 kr but not at the higher levels employed. With increased doses of irradiation, there was a decrease in the percentage of eggs hatching. The dominant lethal effect was observed in cultures with males exposed to 20 kr and higher doses. In cultures with irradiated females, this phenomenon was observed at 40 kr and higher levels. (auth)« less

Improvement of foaming ability of egg white product by irradiation and its application

NASA Astrophysics Data System (ADS)

Song, Hyun-Pa; Kim, Binna; Choe, Jun-Ho; Jung, Samooel; Kim, Kyong-Su; Kim, Dong-Ho; Jo, Cheorun

2009-03-01

To investigate the enhancement of foaming abilities of liquid egg white (LEW) and egg white powder (EWP) by irradiation and its application for bakery product, LEW and EWP were irradiated at 0, 1, 2, and 5 kGy by Co-60 gamma ray. There was no pH change found among treatments in both LEW and EWP. The viscosity of LEW decreased significantly by irradiation ( P<0.05), whereas that of EWP was not affected by irradiation. The foaming ability of LEW and EWP was significantly increased by irradiation as a dose-dependent manner ( P<0.05). The volume and the height of angel cake baked with irradiated LEW were significantly higher than those of unirradiated control ( P<0.05). For EWP, the volume and the height of angel cake were greater at 2 kGy only than those of control. A significant decrease in hardness, chewiness, and gumminess values and an increase in Hunter L* value were observed in the angel cakes prepared from irradiated egg white products ( P<0.05). Results indicated that irradiation of egg white could offer advantages in increasing foaming ability and improving quality of final bakery products.

Expression of Filaggrin and its Degradation Products in Human Skin Following Erythemal Doses of Ultraviolet B Irradiation.

PubMed

Simonsen, Stine; Thyssen, Jacob P; Heegaard, Steffen; Kezic, Sanja; Skov, Lone

2017-07-06

Epidermal filaggrin level is affected by ultraviolet B irradiation in animal and experimental models. This study examined the effect of ultraviolet B irradiation on epidermal filaggrin and natural moisturizing factors in vivo in healthy adults (n = 22). Participants were irradiated with 2 minimal erythema doses of ultraviolet B on the skin. Biopsies and tape strips were collected from skin irradiated 24 and 72 h earlier and from non-irradiated skin (control). Real-time quantitative PCR on skin biopsies showed significantly reduced profilaggrin mRNA expression 24 h after irradiation (mean relative mRNA expression ± standard deviation: control, 3.86 ± 2.06 vs. 24 h, 1.52 ± 0.640; p = 0.02; n = 8). Immunohistochemistry showed aberrant spatial distribution of filaggrin protein 72 h after irradiation (n = 3). High-pressure liquid chromatography of tape extracts showed no change in mean total natural moisturizing factor levels after irradiation, but mean trans-urocanic acid was significantly reduced, as expected (n = 8). In conclusion, erythemal doses of ultraviolet B exert acute effects on profilaggrin mRNA and filaggrin protein in human skin in vivo.

Different doses of partial liver irradiation promotes hepatic regeneration in rat

PubMed Central

Liu, Ying; Shi, Changzheng; Cui, Meng; Yang, Zhenhua; Gan, Danhui; Wang, Yiming

2015-01-01

The aim of this study is to investigate whether partial liver irradiation promotes hepatic regeneration in rat. Left-half liver of rat was irradiated to 10 Gy, and the Right-half to 0, 5, 10 and 15 Gy, respectively. Then, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels were evaluated on 0 day, 15-day, 30-day, 45-day and 60-day after liver irradiation. Next, the serum HGF, NF-κB and TGF-β1 levels were also analyzed on 60-day after liver irradiation. Lastly, the cyclinD1 protein expression was appraised by western blots on 60-day after liver irradiation. ALT, AST and ALP levels were reduced compared with that of controls. The serum HGF, NF-κB and TGF-β1 levels, and the cyclinD1 protein expression in liver irradiation group were increased compared with that of controls group. However, hepatic regeneration of higher dose-irradiated cirrhotic liver was triggered a more enhanced regeneration, compared with that of higher doses group. In summary, these results suggest that different doses of partial liver irradiation promotes hepatic regeneration in rat. PMID:26261535

Capability to Recover Plutonium-238 in H-Canyon/HB-Line - 13248

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuller, Kenneth S. Jr.; Smith, Robert H. Jr.; Goergen, Charles R.

2013-07-01

Plutonium-238 is used in Radioisotope Thermoelectric Generators (RTGs) to generate electrical power and in Radioisotope Heater Units (RHUs) to produce heat for electronics and environmental control for deep space missions. The domestic supply of Pu-238 consists of scrap material from previous mission production or material purchased from Russia. Currently, the United States has no significant production scale operational capability to produce and separate new Pu-238 from irradiated neptunium-237 targets. The Department of Energy - Nuclear Energy is currently evaluating and developing plans to reconstitute the United States capability to produce Pu-238 from irradiated Np-237 targets. The Savannah River Site hadmore » previously produced and/or processed all the Pu-238 utilized in Radioisotope Thermoelectric Generators (RTGs) for deep space missions up to and including the majority of the plutonium for the Cassini Mission. The previous full production cycle capabilities included: Np- 237 target fabrication, target irradiation, target dissolution and Np-237 and Pu-238 separation and purification, conversion of Np-237 and Pu-238 to oxide, scrap recovery, and Pu-238 encapsulation. The capability and equipment still exist and could be revitalized or put back into service to recover and purify Pu-238/Np-237 or broken General Purpose Heat Source (GPHS) pellets utilizing existing process equipment in HB-Line Scrap Recovery, and H-Canyon Frame Waste Recovery processes. The conversion of Np-237 and Pu-238 to oxide can be performed in the existing HB-Line Phase-2 and Phase- 3 Processes. Dissolution of irradiated Np-237 target material, and separation and purification of Np-237 and Pu-238 product streams would be possible at production rates of ∼2 kg/month of Pu-238 if the existing H-Canyon Frames Process spare equipment were re-installed. Previously, the primary H-Canyon Frames equipment was removed to be replaced: however, the replacement project was stopped. The spare equipment is stored and still available for installation. Out of specification Pu-238 scrap material can be purified and recovered by utilizing the HB-Line Phase- 1 Scrap Recovery Line and the Phase-3 Pu-238 Oxide Conversion Line along with H-Canyon Frame Waste Recovery process. In addition, it also covers and describes utilizing the Phase-2 Np-237 Oxide Conversion Line, in conjunction with the H-Canyon Frames Process to restore the H-Canyon capability to process and recover Np-237 and Pu-238 from irradiated Np-237 targets and address potential synergies with other programs like recovery of Pu-244 and heavy isotopes of curium from other target material. (authors)« less

Thermoluminscence of irradiated herbs and spices

NASA Astrophysics Data System (ADS)

Mamoon, A.; Abdul-Fattah, A. A.; Abulfaraj, W. H.

1994-07-01

Several types of herbs and spices from the local market were irradiated with different doses of γ radiations. Doses varied from a few kilograys to 10 kilograys. Thermoluminescence of the irradiated samples and their controls was investigated. For the same type of herb or spice glow curves of different magnitudes, corresponding somewhat to the doses given, were obtained from the irradiated samples. Most control samples gave little or insignificant glow. Glow curves from different herbs and spices irradiated with the same doses were not similar in the strength of the glow signal given. Samples of the black pepper obtained from different packages sometimes give glow curves of very different intensities. Samples from irradiated black pepper were found to show little fading of their glow curves even at 9 months postirradiation. All irradiations were done under the same experimental conditions and at a dose rate of approximately 1 kGy h-1. The glow curves were obtained using a heating rate of about 9°C s-1 and a constant nitrogen flow rate.

Intervention strategies for control of foodborne pathogens

NASA Astrophysics Data System (ADS)

Juneja, Vijay K.

2004-03-01

The increasing numbers of illnesses associated with foodborne pathogens such as Listeria monocytogenes and Escherichia coli O157:H7, has renewed concerns about food safety because of consumer preferences for minimally processed foods that offer convenience in availability and preparation. Accordingly, the need for better control of foodborne pathogens has been paramount in recent years. Mechanical removal of microorganisms from food can be accomplished by centrifugation, filtration, trimming and washing. Cleaning and sanitation strategies can be used for minimizing the access of microorganisms in foods from various sources. Other strategies for control of foodborne pathogens include established physical microbiocidal treatments such as ionizing radiation and heating. Research has continued to demonstrate that food irradiation is a suitable process to control and possibly eliminate foodborne pathogens, for example Listeria monocytogenes and Escherichia coli O157:H7, from a number of raw and cooked meat and poultry products. Heat treatment is the most common method in use today for the inactivation of microorganisms. Microorganisms can also be destroyed by nonthermal treatments, such as application of high hydrostatic pressure, pulsed electric fields, oscillating magnetic fields or a combination of physical processes such as heat-irradiation, or heat-high hydrostatic pressure, etc. Each of the non-thermal technologies has specific applications in terms of the types of food that can be processed. Both conventional and newly developed physical treatments can be used in combination for controlling foodborne pathogens and enhancing the safety and shelf life of foods. Recent research has focused on combining traditional preservation factors with emerging intervention technologies. However, many key issues still need to be addressed for combination preservation factors or technologies to be useful in the food industry to meet public demands for foods with enhanced safety, freshness and appeal. As a result of systematic study in these areas together with detailed assessment of technological performance of available preservatives and preservation technologies in real food formulations, new intervention processes and products are likely to be developed. The ultimate goal is to identify potential new approaches for the safer production of foods. The purpose of this presentation is to discuss key developmental activities concerning microbial reduction by intervention technologies.

Irradiation in the production, processing, and handling of food. Final rule.

PubMed

2005-08-16

The Food and Drug Administration (FDA) is amending the food additive regulations to provide for the safe use of ionizing radiation for control of Vibrio species and other foodborne pathogens in fresh or frozen molluscan shellfish (e.g., oysters, mussels, clams, etc.). This action is in response to a petition filed by the National Fisheries Institute and the Louisiana Department of Agriculture and Forestry.

Effect of low-level laser therapy (λ780 nm) on the mechanically damaged dentin-pulp complex in a model of extrusive luxation in rat incisors.

PubMed

de Santana, Dandara Andrade; Fonseca, Gabriela Ferraz; Ramalho, Luciana Maria Pedreira; Rodriguez, Tânia Tavares; Aguiar, Marcio Cajazeira

2017-12-01

In order to regenerate the dental pulp, many strategies have been developed as phototherapy. In the pulp repair, we do not know if gallium-aluminum-arsenide (GaAlAs) laser preserves the primary odontoblasts or stimulates the formation of more dentin matrix when dental pulp is damaged. The aim of the present study was to examine the effect of laser phototherapy (λ780 nm) on vascularization, inflammation, density of the primary odontoblast layer, and formation of reactionary and reparative dentin in the dental pulp by provoking extrusion of the rat incisor. The upper incisors were extruded 3 mm and then repositioned into their original sockets followed by a laser irradiation of the palatal mucosa (λ = 780 nm; p = 70 mW; CW; 4.2 J/cm 2 ; 60 s) every 48 h. Non-traumatized and/or non-irradiated incisors were used as the controls. At 8 and 30 days after surgery, incisors were processed for histological and histomorphometric analysis. Morphological analysis revealed no differences in vascularization between groups, but showed discrete inflammation in some non-irradiated and injured specimens, which correlated with a more irregular reparative dentin. The density of primary odontoblasts in the groups treated with lasers was higher when compared to non-irradiated groups, but no statistically significant difference between groups (p > 0.05). The thickness of the tertiary dentin was increased in both traumatized groups with no statistically significant difference between non-irradiated and irradiated groups (p > 0.05).The present findings revealed that the GaAlAs laser induced small changes on dentin-pulp complex, with more regular dentin matrix in the irradiated dental pulps.

Effects of prenatal X-irradiation on postnatal testicular development and function in the Wistar rat: development/teratology/behavior/radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jensh, R.P.; Brent, R.L.

1988-11-01

It is evident that significant permanent tissue hypoplasia can be produced following radiation exposure late in fetal development. Because two organs, brain and testes, are developmentally and functionally interrelated, it was of interest to determine whether fetal testicular hypoplasia was a primary or a secondary effect of fetal brain irradiation. Twenty-four pregnant Wistar strain rats were randomly assigned to one of four groups, and a laparotomy was performed on day 18 of gestation. The fetuses received sham irradiation, whole body irradiation, or only head/thorax or pelvic body irradiation at a dosage level of 1.5 Gy. Mothers were allowed to delivermore » and raise their offspring until postnatal day 30, when the offspring were weaned. At 60 days of age, 74 male offspring were allowed to mate with colony control females of similar age until successful insemination or until the males reached 90 days of age, when they were killed. Testes were weighed and processed for histologic examination. Direct radiation of testes, due to whole body or pelvic exposure, resulted in testicular growth retardation and significantly reduced spermatogenesis. Breeding activity of the males and the percent of positive inseminations were also slightly reduced. However, a significant percentage of male offspring receiving direct testicular radiation did produce offspring. Head/thorax-only irradiation did not adversely affect testicular growth or spermatogenesis. Therefore, the use of histologic analysis as the sole determinant of infertility may be misleading. This study indicates that testicular growth retardation and an increased infertility rate result from direct prenatal exposure of rat testes to X-radiation and are not necessarily mediated via X-irradiation effects on the central nervous system.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rupich, Martin W.; Sathyamurthy, Srivatsan; Fleshler, Steven

We demonstrate a twofold increase in the in-field critical current of AMSC's standard 2G coil wire by irradiation with 18-MeV Au ions. The optimum pinning enhancement is achieved with a dose of 6 × 10 11 Au ions/cm 2. Although the 77 K, self-field critical current is reduced by about 35%, the in-field critical current (H//c) shows a significant enhancement between 4 and 50 K in fields > 1 T. The process was used for the roll-to-roll irradiation of AMSC's standard 46-mm-wide production coated conductor strips, which were further processed into standard copper laminated coil wire. The long-length wires showmore » the same enhancement as attained with short static irradiated samples. The roll-to-roll irradiation process can be incorporated in the standard 2G wire manufacturing, with no modifications to the current process. In conclusion, the enhanced performance of the wire will benefit rotating machine and magnet applications.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rupich, Martin W.; Sathyamurthy, Srivatsan; Fleshler, Steven

We demonstrate a twofold increase in the in-field critical current of AMSC's standard 2G coil wire by irradiation with 18-MeV Au ions. The optimum pinning enhancement is achieved with a dose of 6 x 10(11) Au ions/cm(2). Although the 77 K, self-field critical current is reduced by about 35%, the in-field critical current (H//c) shows a significant enhancement between 4 and 50 K in fields > 1 T. The process was used for the roll-to-roll irradiation of AMSC's standard 46-mm-wide production coated conductor strips, which were further processed into standard copper laminated coil wire. The long-length wires show the samemore » enhancement as attained with short static irradiated samples. The roll-to-roll irradiation process can be incorporated in the standard 2G wire manufacturing, with no modifications to the current process. The enhanced performance of the wire will benefit rotating machine and magnet applications.« less

Effect of combination of chitosan coating and irradiation on physicochemical and functional properties of chicken egg during room-temperature storage

NASA Astrophysics Data System (ADS)

Liu, Xian De; Jang, Aera; Kim, Dong Hun; Lee, Bong Duk; Lee, Mooha; Jo, Cheorun

2009-07-01

The effect of combination of chitosan coating and irradiation on quality and storage stability of shell egg was investigated. Salmonella typhimurium inoculated on eggshell was not detected by irradiation of 2.0 kGy at day 0 and/or chitosan coating (1%, pH 5.0) after 3 days of storage. One-day-old fresh chicken egg was chitosan coated and irradiated at 0, 0.5, 1.0, 1.5 and 2.0 kGy by gamma ray. The egg samples were stored at room temperature for 14 days and the effects of the combination treatment on internal physicochemical and functional properties were investigated. The Haugh unit of egg was decreased by irradiation even at 0.5 kGy. Irradiation increased the lipid oxidation in egg yolk at 2 kGy but the egg with chitosan coating reduced the level of lipid oxidation. Irradiation increased the foaming ability of egg white and decreased viscosity of egg yolk and white. Results suggested that combination of irradiation and chitosan coating can improve safety of shell egg but irradiation treatment may reduce the egg quality for direct consumption. However, an improved functional property for further processing and efficient separation of egg white and yolk can be expected for egg processing industry using irradiation.

Radiosensitivity study and radiation effects on morphology characterization of grey oyster mushroom Pleurotus sajor-caju

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rashid, Rosnani Abdul; Awang, Mat Rasol; Mohamad, Azhar

2014-09-03

Radiosensitive dosage and morphology characterization of irradiated grey oyster mushroom Pleurotus sajor-caju by gamma rays was investigated due to effects of irradiation. In order to establish the effect, mycelium of P. sajor-caju was irradiated by gamma rays at dose 0.1 to 8.0 kGy with dose rate 0.227 Gy sec{sup −1}. The irradiation of mycelia was carried out at the radiation facility in Malaysian Nuclear Agency. The radiosensitivity study was performed by evaluating the percentage of survival irradiated mycelia. The lethal dose of the mycelium P. sajor-caju was determined at 4.0 kGy and LD{sub 50} to be equal at 2.2 kGy.more » The radiation effects on morphology were evaluated based on growth rate of irradiated mycelia, mycelia types, colonization period on substrate, morphology of fruit bodies and yields. The results shown growth rate of irradiated mycelium was slightly lower than the control and decreased as the dose increased. Irradiation was found can induced the primordia formation on PDA and the BE of irradiated seed is higher than to control. The irradiation is proven to be useful for generating new varieties of mushroom with commercial value to the industry.« less

Stimulatory Effects of Gamma Irradiation on Phytochemical Properties, Mitotic Behaviour, and Nutritional Composition of Sainfoin (Onobrychis viciifolia Scop.)

PubMed Central

Mat Taha, Rosna; Lay, Ma Ma; Khalili, Mahsa

2014-01-01

Sainfoin (Onobrychis viciifolia Scop. Syn. Onobrychis sativa L.) is a bloat-safe forage crop with high levels of tannins, which is renowned for its medicinal qualities in grazing animals. Mutagenesis technique was applied to investigate the influence of gamma irradiation at 30, 60, 90, and 120 Gy on mitotic behavior, in vitro growth factors, phytochemical and nutritional constituents of sainfoin. Although a percentage of plant necrosis and non-growing seed were enhanced by irradiation increment, the germination speed was significantly decreased. It was observed that gamma irradiated seeds had higher value of crude protein and dry matter digestibility compared to control seeds. Toxicity of copper was reduced in sainfoin irradiated seeds at different doses of gamma rays. Anthocyanin content also decreased in inverse proportion to irradiation intensity. Accumulation of phenolic and flavonoid compounds was enhanced by gamma irradiation exposure in leaf cells. HPLC profiles differed in peak areas of the two important alkaloids, Berberine and Sanguinarine, in 120 Gy irradiated seeds compared to control seeds. There were positive correlations between irradiation dose and some abnormality divisions such as laggard chromosome, micronucleus, binucleated cells, chromosome bridge, and cytomixis. In reality, radiocytological evaluation was proven to be essential in deducing the effectiveness of gamma irradiation to induce somaclonal variation in sainfoin. PMID:25147870

The role of granulocyte macrophage colony stimulating factor (GM-CSF) in radiation-induced tumor cell migration.

PubMed

Vilalta, Marta; Brune, Jourdan; Rafat, Marjan; Soto, Luis; Graves, Edward E

2018-03-13

Recently it has been observed in preclinical models that that radiation enhances the recruitment of circulating tumor cells to primary tumors, and results in tumor regrowth after treatment. This process may have implications for clinical radiotherapy, which improves control of a number of tumor types but which, despite continued dose escalation and aggressive fractionation, is unable to fully prevent local recurrences. By irradiating a single tumor within an animal bearing multiple lesions, we observed an increase in tumor cell migration to irradiated and unirradiated sites, suggesting a systemic component to this process. Previous work has identified the cytokine GM-CSF, produced by tumor cells following irradiation, as a key effector of this process. We evaluated the ability of systemic injections of a PEGylated form of GM-CSF to stimulate tumor cell migration. While increases in invasion and migration were observed for tumor cells in a transwell assay, we found that daily injections of PEG-GM-CSF to tumor-bearing animals did not increase migration of cells to tumors, despite the anticipated changes in circulating levels of granulocytes and monocytes produced by this treatment. Combination of PEG-GM-CSF treatment with radiation also did not increase tumor cell migration. These findings suggest that clinical use of GM-CSF to treat neutropenia in cancer patients will not have negative effects on the aggressiveness of residual cancer cells. However, further work is needed to characterize the mechanism by which GM-CSF facilitates systemic recruitment of trafficking tumor cells to tumors.

Improvement of shelf stability and processing properties of meat products by gamma irradiation

NASA Astrophysics Data System (ADS)

Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Lee, Kyong-Haeng; Kim, Hee-Yun

2002-03-01

To evaluate the effects of gamma irradiation on the processing properties of meat products, emulsion-type sausage, beef patties and pork loin ham were manufactured. Most contaminated bacteria were killed by 3 kGy-irradiation to raw ground beef, and sausage can be manufactured with desirable flavor, a reduction of NaCl and phosphate, and extension of shelf life using gamma irradiation on the raw meat. The beef patties were manufactured with the addition of antioxidants (200 ppm), BHA, ascorbyl palmitate, α-tocopherol, or β-carotene, and gamma-irradiation. Retardation of lipid oxidation appeared at the patties with an antioxidant. A dose of 5 kGy was observed to be as effective as the use of 200 ppm NaNO 2 to provide and maintain the desired color of the product during storage. After curing, irradiation, heating and smoking could extensively prolong the shelf life of the hams.

Effect of Irradiation on Tissue Penetration Depth of Doxorubicin after Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) in a Novel Ex-Vivo Model.

PubMed

Khosrawipour, Veria; Giger-Pabst, Urs; Khosrawipour, Tanja; Pour, Yousef Hedayat; Diaz-Carballo, David; Förster, Eckart; Böse-Ribeiro, Hugo; Adamietz, Irenäus Anton; Zieren, Jürgen; Fakhrian, Khashayar

2016-01-01

This study was performed to assess the impact of irradiation on the tissue penetration depth of doxorubicin delivered during Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC). Fresh post mortem swine peritoneum was cut into 10 proportional sections. Except for 2 control samples, all received irradiation with 1, 2, 7 and 14 Gy, respectively. Four samples received PIPAC 15 minutes after irradiation and 4 other after 24 hours. Doxorubicin was aerosolized in an ex-vivo PIPAC model at 12 mmHg/36°C. In-tissue doxorubicin penetration was measured using fluorescence microscopy on frozen thin sections. Doxorubicin penetration after PIPAC (15 minutes after irradiation) was 476 ± 74 µm for the control sample, 450 ± 45µm after 1 Gy (p > 0.05), 438 ± 29 µm after 2 Gy (p > 0.05), 396 ± 32 µm after 7 Gy (p = 0.005) and 284 ± 57 after 14 Gy irradiation (p < 0.001). The doxorubicin penetration after PIPAC (24 hours after irradiation) was 428 ± 77 µm for the control sample, 393 ± 41 µm after 1 Gy (p > 0.05), 379 ± 56 µm after 2 Gy (p > 0.05), 352 ± 53 µm after 7 Gy (p = 0.008) and 345 ± 53 after 14 Gy irradiation (p = 0.001). Higher (fractional) radiation dose might reduce the tissue penetration depth of doxorubicin in our ex-vivo model. However, irradiation with lower (fractional) radiation dose does not affect the tissue penetration negatively. Further studies are warranted to investigate if irradiation can be used safely as chemopotenting agent for patients with peritoneal metastases treated with PIPAC.

Space Plasma Ion Processing of Ilmenite in the Lunar Soil: Insights from In-Situ TEM Ion Irradiation Experiments

NASA Technical Reports Server (NTRS)

Christoffersen, R.; Keller, L. P.

2007-01-01

Space weathering on the moon and asteroids results largely from the alteration of the outer surfaces of regolith grains by the combined effects of solar ion irradiation and other processes that include deposition of impact or sputter-derived vapors. Although no longer considered the sole driver of space weathering, solar ion irradiation remains a key part of the space weathering puzzle, and quantitative data on its effects on regolith minerals are still in short supply. For the lunar regolith, previous transmission electron microscope (TEM) studies performed by ourselves and others have uncovered altered rims on ilmenite (FeTiO3) grains that point to this phase as a unique "witness plate" for unraveling nanoscale space weathering processes. Most notably, the radiation processed portions of these ilmenite rims consistently have a crystalline structure, in contrast to radiation damaged rims on regolith silicates that are characteristically amorphous. While this has tended to support informal designation of ilmenite as a "radiation resistant" regolith mineral, there are to date no experimental data that directly and quantitatively compare ilmenite s response to ion radiation relative to lunar silicates. Such data are needed because the radiation processed rims on ilmenite grains, although crystalline, are microstructurally and chemically complex, and exhibit changes linked to the formation of nanophase Fe metal, a key space weathering process. We report here the first ion radiation processing study of ilmenite performed by in-situ means using the Intermediate Voltage Electron Microscope- Tandem Irradiation facility (IVEM-Tandem) at Argonne National Laboratory. The capability of this facility for performing real time TEM observations of samples concurrent with ion irradiation makes it uniquely suited for studying the dose-dependence of amorphization and other changes in irradiated samples.

Mice receiving infrared irradiation have a higher survival rate under forced swimming in cold.

PubMed

Tsai, Jui-Feng

2009-10-01

To explore the effect of infrared (IR) irradiation on the survival rates of mice under forced swimming in cold conditions. IR irradiation has been found to be beneficial for wound healing, tumor reduction, pain relief, and even against depression. However, whether the antidepressant effect of IR irradiation came from heat has remained unanswered. The goals of the study were originally aimed at using an animal model for depression to understand the relationship between the antidepressant effect of IR irradiation and hyperthermia as well as seasonality. Forty-four mice were housed in cages in a room subject to the outdoor temperature, and randomly assigned to the IR-treated group (n = 15), the heat-treated group (n = 14), and the control group (n = 15) during winter. The mice of the IR-treated group received whole-body IR irradiation for 60 min daily, while the heat-treated group received heat diffusion to reach the same temperature level. The control group received neither IR nor heat. All groups of mice underwent a forced swimming test weekly. Incidentally, two episodes of cold current occurred during the study period, and some mice died. The survival rates were compared pairwise against the control. The IR-treated group had a significantly reduced relative risk (p = 0.013) when compared with the control group, while the heat-treated group did not show any significant reduction (p = 0.087). There was no significant difference in body temperatures of the three groups before and after the irradiation. IR irradiation resulted in a significantly higher survival rate for mice that were concurrently subjected to cold and a forced swimming test. This result may be beyond the thermal effect.

Protective effects of melatonin against 12C6+ beam irradiation-induced oxidative stress and DNA injury in the mouse brain

NASA Astrophysics Data System (ADS)

Wu, Z. H.; Zhang, H.; Wang, X. Y.; Yang, R.; Liu, B.; Liu, Y.; Zhao, W. P.; Feng, H. Y.; Xue, L. G.; Hao, J. F.; Niu, B. T.; Wang, Z. H.

2012-01-01

The purpose of this experiment was to estimate the protective effects of melatonin against radiation-induced brain damages in mice induced by heavy ion beams. Kun-Ming mice were randomly divided into five groups: normal control group, irradiation control group, and three different doses of melatonin (5, 10, and 20 mg/kg, i.p.) treated groups. Apart from the normal control group, the other four groups were exposed to whole-body 4.0 Gy carbon ion beam irradiation (approximately 0.5 Gy/min) after i.p. administration of normal saline or melatonin 1 h before irradiation. The oxidative redox status of brain tissue was assessed by measurement of malondiadehyde (MDA) levels, total superoxide dismutase (T-SOD), cytosolic superoxide dismutase (Cu/ZnSOD, SOD1) and mitochondrial superoxide dismutase (MnSOD, SOD2) activities at 8 h after irradiation. DNA damages were determined using the Comet assay and apoptosis and cell cycle distribution were detected by flow cytometric analyses. A dramatic dose-dependent decrease in MDA levels, tail moment, rates of tailing cells, and apoptosis, and a dose-dependent increase in T-SOD and SOD2 activities, in brain tissues in the melatonin-treated groups were detected compared with the irradiation only group. Furthermore, flow cytometric analysis demonstrated that the percentage of brain cells in the G0/G1 phase decreased significantly, while those in the S and G2/M stage increased dramatically, with mice pretreated with melatonin compared to the irradiation control group. These data indicate that melatonin has protective effects against irradiation-induced brain injury, and that its underlying protective mechanisms may relate to modulation of oxidative stress induced by heavy ionirradiation.

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice

PubMed Central

Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil

2014-01-01

BACKGROUND/OBJECTIVES Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. MATERIALS/METHODS Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). RESULTS The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. CONCLUSIONS Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression. PMID:25110559

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice.

PubMed

Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil; Hwang, Jae-Kwan

2014-08-01

Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression.

A multifunctional setup to record FTIR and UV-vis spectra of organic molecules and their photoproducts in astronomical ices.

PubMed

Kofman, V; Witlox, M J A; Bouwman, J; Ten Kate, I L; Linnartz, H

2018-05-01

This article describes a new, multi-functional, high-vacuum ice setup that allows to record the in situ and real-time spectra of vacuum UV (VUV)-irradiated non-volatile molecules embedded in a low-temperature (10 K) amorphous solid water environment. Three complementary diagnostic tools-UV-visible (UV-vis) and Fourier Transform Infrared (FTIR) spectroscopy and temperature-programmed desorption quadrupole mass spectrometry-can be used to simultaneously study the physical and chemical behavior of the organic molecules in the ice upon VUV irradiation. The setup is equipped with a temperature-controlled sublimation oven that enables the controlled homogeneous deposition of solid species such as amino acids, nucleobases, and polycyclic aromatic hydrocarbons (PAHs) in ice mixtures prepared from precursor gases and/or liquids. The resulting ice is photo-processed with a microwave discharge hydrogen lamp, generating VUV radiation with a spectral energy distribution representative for the interstellar medium. The characteristics, performance, and future potential of the system are discussed by describing three different applications. First, a new method is introduced, which uses broadband interference transmission fringes recorded during ice deposition, to determine the wavelength-dependent refractive index, n λ , of amorphous solid water. This approach is also applicable to other solids, pure and mixed. Second, the UV-vis and FTIR spectroscopy of an VUV-irradiated triphenylene:water ice mixture is discussed, monitoring the ionization efficiency of PAHs in interstellar ice environments. The third and final example investigates the stability of solid glycine upon VUV irradiation by monitoring the formation of dissociation products in real time.

A multifunctional setup to record FTIR and UV-vis spectra of organic molecules and their photoproducts in astronomical ices

NASA Astrophysics Data System (ADS)

Kofman, V.; Witlox, M. J. A.; Bouwman, J.; ten Kate, I. L.; Linnartz, H.

2018-05-01

This article describes a new, multi-functional, high-vacuum ice setup that allows to record the in situ and real-time spectra of vacuum UV (VUV)-irradiated non-volatile molecules embedded in a low-temperature (10 K) amorphous solid water environment. Three complementary diagnostic tools—UV-visible (UV-vis) and Fourier Transform Infrared (FTIR) spectroscopy and temperature-programmed desorption quadrupole mass spectrometry—can be used to simultaneously study the physical and chemical behavior of the organic molecules in the ice upon VUV irradiation. The setup is equipped with a temperature-controlled sublimation oven that enables the controlled homogeneous deposition of solid species such as amino acids, nucleobases, and polycyclic aromatic hydrocarbons (PAHs) in ice mixtures prepared from precursor gases and/or liquids. The resulting ice is photo-processed with a microwave discharge hydrogen lamp, generating VUV radiation with a spectral energy distribution representative for the interstellar medium. The characteristics, performance, and future potential of the system are discussed by describing three different applications. First, a new method is introduced, which uses broadband interference transmission fringes recorded during ice deposition, to determine the wavelength-dependent refractive index, nλ, of amorphous solid water. This approach is also applicable to other solids, pure and mixed. Second, the UV-vis and FTIR spectroscopy of an VUV-irradiated triphenylene:water ice mixture is discussed, monitoring the ionization efficiency of PAHs in interstellar ice environments. The third and final example investigates the stability of solid glycine upon VUV irradiation by monitoring the formation of dissociation products in real time.

The Effect of Postmastectomy Radiation Therapy on Breast Implants: Material Analysis on Silicone and Polyurethane Prosthesis.

PubMed

Lo Torto, Federico; Relucenti, Michela; Familiari, Giuseppe; Vaia, Nicola; Casella, Donato; Matassa, Roberto; Miglietta, Selenia; Marinozzi, Franco; Bini, Fabiano; Fratoddi, Ilaria; Sciubba, Fabio; Cassese, Raffaele; Tombolini, Vincenzo; Ribuffo, Diego

2018-05-17

The pathogenic mechanism underlying capsular contracture is still unknown. It is certainly a multifactorial process, resulting from human body reaction, biofilm activation, bacteremic seeding, or silicone exposure. The scope of the present article is to investigate the effect of hypofractionated radiotherapy protocol (2.66 Gy × 16 sessions) both on silicone and polyurethane breast implants. Silicone implants and polyurethane underwent irradiation according to a hypofractionated radiotherapy protocol for the treatment of breast cancer. After irradiation implant shells underwent mechanical, chemical, and microstructural evaluation by means of tensile testing, infrared spectra in attenuated total reflectance mode, nuclear magnetic resonance, and field emission scanning electron microscopy. At superficial analysis, irradiated silicone samples show several visible secondary and tertiary blebs. Polyurethane implants showed an open cell structure, which closely resembles a sponge. Morphological observation of struts from treated polyurethane sample shows a more compact structure, with significantly shorter and thicker struts compared with untreated sample. The infrared spectra in attenuated total reflectance mode spectra of irradiated and control samples were compared either for silicon and polyurethane samples. In the case of silicone-based membranes, treated and control specimens showed similar bands, with little differences in the treated one. Nuclear magnetic resonance spectra on the fraction soluble in CDCl3 support these observations. Tensile tests on silicone samples showed a softer behavior of the treated ones. Tensile tests on Polyurethane samples showed no significant differences. Polyurethane implants seem to be more resistant to radiotherapy damage, whereas silicone prosthesis showed more structural, mechanical, and chemical modifications.

Trace concentrations of vitamin E protect radiation crosslinked UHMWPE from oxidative degradation.

PubMed

Kurtz, S M; Dumbleton, J; Siskey, R S; Wang, A; Manley, M

2009-08-01

The effect of very low concentrations of Vitamin E on the stability and mechanical behavior of UHMWPE remains unknown. We tested the hypothesis that the oxidation resistance of Vitamin E-blended UHMWPE would be influenced by trace doses of antioxidant, resin, and radiation treatment. Trace concentrations (< or =500 ppm w/w%) of alpha-tocopherol (Vitamin E) were blended separately with GUR 1020 and 1050 resins and molded into disks. From each disk, three groups of 10 mm thick blocks were machined: (1) no irradiation (control); (2) 30 kGy of gamma irradiation in nitrogen; and (3) 75 kGy of gamma irradiation in air. Specimens were subjected to three aging protocols: (a) no aging (control); (b) two weeks and (c) four weeks of accelerated aging in accordance with ASTM F 2003 (i.e., 70 degrees C and 5 atm oxygen). The minimum concentration of Vitamin E needed to stabilize UHMWPE during our accelerated tests depended upon the method of radiation processing. For the 30 and 75 kGy irradiated materials, the addition of 125 ppm or more Vitamin E was sufficient to maintain baseline mechanical and chemical properties through two weeks of accelerated aging. For these groups, the addition of 375 ppm or 500 ppm, respectively, was necessary to maintain baseline mechanical and chemical properties throughout the four-week accelerated aging period. UHMWPE resin molecular weight did not have an effect on oxidation behavior. The results of this experiment therefore supported our hypotheses that trace concentrations of Vitamin E, coupled with radiation treatment-but not resin grade-influence the mechanical and oxidative degradation behavior of UHMWPE.

Optical metabolic imaging of irradiated rat heart exposed to ischemia-reperfusion injury

NASA Astrophysics Data System (ADS)

la Cour, Mette Funding; Mehrvar, Shima; Heisner, James S.; Motlagh, Mohammad Masoudi; Medhora, Meetha; Ranji, Mahsa; Camara, Amadou K. S.

2018-01-01

Whole thoracic irradiation (WTI) is known to cause deterioration in cardiac function. Whether irradiation predisposes the heart to further ischemia and reperfusion (IR) injury is not well known. The aim of this study is to examine the susceptibility of rat hearts to IR injury following a single fraction of 15 Gy WTI and to investigate the role of mitochondrial metabolism in the differential susceptibility to IR injury. After day 35 of irradiation, ex vivo hearts from irradiated and nonirradiated rats (controls) were exposed to 25-min global ischemia followed by 60-min IR, or hearts were perfused without IR for the same protocol duration [time controls (TC)]. Online fluorometry of metabolic indices [redox state: reduced nicotinamide adenine dinucleotide (NADH), oxidized flavin adenine dinucleotide (FAD), and NADH/FAD redox ratio] and functional variables [systolic left ventricular pressure (LVP), diastolic LVP (diaLVP), coronary flow (CF), and heart rate were recorded in the beating heart; developed LVP (dLVP) and rate pressure product (RPP)] were derived. At the end of each experimental protocol, hearts were immediately snap frozen in liquid N2 for later three-dimensional imaging of the mitochondrial redox state using optical cryoimaging. Irradiation caused a delay in recovery of dLVP and RPP after IR when compared to nonirradiated hearts but recovered to the same level at the end of reperfusion. CF in the irradiated hearts recovered better than the control hearts after IR injury. Both fluorometry and 3-D cryoimaging showed that in WTI and control hearts, the redox ratio increased during ischemia (reduced) and decreased on reperfusion (oxidized) when compared to their respective TCs; however, there was no significant difference in the redox state between WTI and controls. In conclusion, our results show that although irradiation of rat hearts compromised baseline cardiovascular function, it did not alter cardiac mitochondrial redox state and induce greater susceptibility of these hearts to IR injury.

Effect of laser irradiation for healing of the skin-muscle wounds of animals

NASA Astrophysics Data System (ADS)

Lapina, Victoria A.; Veremei, Eduard I.; Pancovets, Evgeniy A.

2000-05-01

The purpose of our investigation was to study the medical effect of low-intensity laser influence on healing of skin- muscle wounds of agricultural animals. We used the laser radiation of low intensity for cub's therapy: to sucking-pigs after herniotomy and castration, to cattle cubs after skin- muscle wounds. The animals were kept under clinical observation up to their recovery. The recuperation dynamic was observed by changing of blood quotients, leukograms, sizes of inflammatory edema, general behavior of animals. The positive dynamic of blood quotients of the experimental animal groups was really higher than that in control. The analysis of wound healing after laser influence shows that wound surface of experimental group was to a great extent smaller in comparison with control group of animals. So, these facts testify about anti-inflammatory action of laser radiation, which hastens regenerative and rehabilitative processes. Analysis of the obtained experimental data has revealed the positive influence of laser irradiation on the dynamics of wound adhesion of agricultural animals.

Method and apparatus for controlled size distribution of gel microspheres formed from aqueous dispersions. [Patent application

DOEpatents

Ryon, A.D.; Haas, P.A.; Vavruska, J.S.

1982-01-19

The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. This is accomplished by subjecting aqueous dispersions of a sol, within a water-immiscible organic liquid to a turbulent flow. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.

Acceptability of minimally processed and irradiated pineapple and watermelon among Brazilian consumers

NASA Astrophysics Data System (ADS)

Martins, Cecília Geraldes; Aragon-Alegro, Lina Casale; Behrens, Jorge Herman; Oliveira Souza, Kátia Leani; Martins Vizeu, Dirceu; Hutzler, Beatriz Weltman; Teresa Destro, Maria; Landgraf, Mariza

2008-06-01

This study aimed at evaluating the acceptance of MP watermelon and pineapple exposed to 1.0 and 2.5 kGy compared to non-irradiated samples. No significant differences were observed in liking between irradiated and non-irradiated samples, and also between doses of 1.0 and 2.5 kGy. Significant differences in sourness (pineapple) or sweetness (watermelon) and between intention of purchase of irradiated and non-irradiated fruits were not observed as well. Results showed that MP watermelon and pineapple could be irradiated with doses up to 2.5 kGy without significant changes in acceptability.

Effect of gamma irradiation on physical characteristics of Jordanian durum wheat and quality of semolina and lasagna products

NASA Astrophysics Data System (ADS)

Azzeh, F. S.; Amr, A. S.

2009-09-01

This study was conducted to determine the effect of using varying gamma irradiation doses on the physiochemical and rheological properties of semolina and its products. Ash, protein and water content were not influenced with gamma irradiation, while falling number and fungi counts decreased with increasing irradiation dose. Irradiation adversely affected wet gluten at 5 kGy dose. Dough stability was deteriorated vigorously with increasing irradiation dose. Sensory evaluation showed that lasagna produced from 0.25- and 1 kGy-irradiated semolina did not show any significant differences as compared with the control sample.

Colour centre recovery in yttria-stabilised zirconia: photo-induced versus thermal processes

NASA Astrophysics Data System (ADS)

Costantini, Jean-Marc; Touati, Nadia; Binet, Laurent; Lelong, Gérald; Guillaumet, Maxime; Beuneu, François

2018-05-01

The photo-annealing of colour centres in yttria-stabilised zirconia (YSZ) was studied by electron paramagnetic resonance spectroscopy upon UV-ray or laser light illumination, and compared to thermal annealing. Stable hole centres (HCs) were produced in as-grown YSZ single crystals by UV-ray irradiation at room temperature (RT). The HCs produced by 200-MeV Au ion irradiation, as well as the F+-type centres (? centres involving oxygen vacancies) were left unchanged upon UV illumination. In contrast, a significant photo-annealing of the latter point defects was achieved in 1.4-MeV electron-irradiated YSZ by 553-nm laser light irradiation at RT. Almost complete photo-bleaching was achieved by laser irradiation inside the absorption band of ? centres centred at a wavelength 550 nm. Thermal annealing of these colour centres was also followed by UV-visible absorption spectroscopy showing full bleaching at 523 K. Colour-centre evolutions by photo-induced and thermally activated processes are discussed on the basis of charge exchange processes between point defects.

Synthesis of IgM and IgG antibodies in mice irradiated with x rays and immunized with tetanus toxoid (in Polish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galazka, A.; Albrycht, H.; Aleksandrowicz, J.

1972-01-01

White mice were immunized with adsorbed tetanus toxoid 1 to 2 hrs following irradiation with a dose of 300 R. The antibody response was tested in whole sera 7, 14, 28, and 42 days after immunization; it was found to be delayed and repressed compared with controls. In tests for antibody activity of different classes of immunoglobulins, isolated on Sephadex G-200, the IgM- producing mechanisms were found to be highly radiosensitive; peak of the response was greatly delayed (28 days); and peak titers were threefold lower than in controls. IgG antibody production also was delayed and in the initial periodmore » it was repressed. Six weeks after irradiation, IgG antibody levels were equal in the irradiated and control mice. The present results concerning radiosensitivity of IgM-producing mechanisms are discordant with data of other authors, who immunized animals with other antigens or investigated the metabolism of immunoglobulins in irradiated but nonimmunized animals. (auth)« less

Quantification of applied dose in irradiated citrus fruits by DNA Comet Assay together with image analysis.

PubMed

Cetinkaya, Nurcan; Ercin, Demet; Özvatan, Sümer; Erel, Yakup

2016-02-01

The experiments were conducted for quantification of applied dose for quarantine control in irradiated citrus fruits. Citrus fruits exposed to doses of 0.1 to 1.5 kGy and analyzed by DNA Comet Assay. Observed comets were evaluated by image analysis. The tail length, tail moment and tail DNA% of comets were used for the interpretation of comets. Irradiated citrus fruits showed the separated tails from the head of the comet by increasing applied doses from 0.1 to 1.5 kGy. The mean tail length and mean tail moment% levels of irradiated citrus fruits at all doses are significantly different (p < 0.01) from control even for the lowest dose at 0.1 kGy. Thus, DNA Comet Assay may be a practical quarantine control method for irradiated citrus fruits since it has been possible to estimate the applied low doses as small as 0.1 kGy when it is combined with image analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snepvangers, J.J.M.

Equipment and results are described connected with irradiation studies of UO/sub 2/ fuels, fuel element testing in pressurized water loops, graphite irradiation, and steel irradiations with and without temperature control. The apparatus described is associated with a 20-Mw pool-type research reactor. (T.F.H.)

Laser processing for manufacturing nanocarbon materials

NASA Astrophysics Data System (ADS)

Van, Hai Hoang

CNTs have been considered as the excellent candidate to revolutionize a broad range of applications. There have been many method developed to manipulate the chemistry and the structure of CNTs. Laser with non-contact treatment capability exhibits many processing advantages, including solid-state treatment, extremely fast processing rate, and high processing resolution. In addition, the outstanding monochromatic, coherent, and directional beam generates the powerful energy absorption and the resultant extreme processing conditions. In my research, a unique laser scanning method was developed to process CNTs, controlling the oxidation and the graphitization. The achieved controllability of this method was applied to address the important issues of the current CNT processing methods for three applications. The controllable oxidation of CNTs by laser scanning method was applied to cut CNT films to produce high-performance cathodes for FE devices. The production method includes two important self-developed techniques to produce the cold cathodes: the production of highly oriented and uniformly distributed CNT sheets and the precise laser trimming process. Laser cutting is the unique method to produce the cathodes with remarkable features, including ultrathin freestanding structure (~200 nm), greatly high aspect ratio, hybrid CNT-GNR emitter arrays, even emitter separation, and directional emitter alignment. This unique cathode structure was unachievable by other methods. The developed FE devices successfully solved the screening effect issue encounter by current FE devices. The laser-control oxidation method was further developed to sequentially remove graphitic walls of CNTs. The laser oxidation process was directed to occur along the CNT axes by the laser scanning direction. Additionally, the oxidation was further assisted by the curvature stress and the thermal expansion of the graphitic nanotubes, ultimately opening (namely unzipping) the tubular structure to produce GNRs. Therefore the developed laser scanning method optimally exploited the thermal laser-CNT interaction, successfully transforming CNTs into 2D GNRs. The solid-state laser unzipping process effectively addressed the issues of contamination and scalability encountered by the current unzipping methods. Additionally, the produced GNRs were uniquely featured with the freestanding structure and the smooth surfaces. If the scanning process was performed in an inert environment without the appearance of oxygen, the oxidation of CNTs would not happen. Instead, the greatly mobile carbon atoms of the heated CNTs would reorganize the crystal structure, inducing the graphitization process to improve the crystallinity. Many observations showing the structural improvement of CNTs under laser irradiation has been reported, confirming the capability of laser to heal graphitic defects. Laser methods were more time-efficient and energy-efficient than other annealing methods because laser can quickly heat CNTs to generate graphitization in less than one second. This subsecond heating process of laser irradiation was more effective than other heating methods because it avoided the undesired coalescence of CNTs. In my research, the laser scanning method was applied to generate the graphitization, healing the structural defects of CNTs. Different from the reported laser methods, the laser scanning directed the locally annealed areas to move along the CNT axes, migrating and coalescencing the graphitic defects to achieve better healing results. The critical information describing the CNT structural transformation caused by the moving laser irradiation was explored from the successful applications of the developed laser method. This knowledge inspires an important method to modifiy the general graphitic structure for important applications, such as carbon fiber production, CNT self-assembly process and CNT welding. This method will be effective, facile, versatile, and adaptable for laboratory and industrial facilities.

Investigation of Thermal Effects of Photocoagulation on Retinal Tissue Using Fine-Motion-Sensitive Dynamic Optical Coherence Tomography.

PubMed

Kurokawa, Kazuhiro; Makita, Shuichi; Yasuno, Yoshiaki

2016-01-01

To enable an objective evaluation of photocoagulation, we characterize thermal tissue changes induced by laser irradiation with different laser parameters using optical coherence tomography (OCT). Spectral-domain OCT with a newly developed image processing method was used to monitor the thermal changes of ex vivo porcine retina. A sequence of OCT B-scans was obtained at the same retinal position simultaneously with the photocoagulation. Cross-sectional tissue displacement maps with respect to an OCT image taken before laser irradiation were computed for images taken before, during, and after laser irradiation, by using a correlation-based custom algorithm. Cross-sectional correlation maps (OCT correlation maps) were also computed from an OCT image taken before laser irradiation as a base-line to visualize alterations of tissue microstructure induced by laser irradiation. By systematically controlling laser power and exposure times, tissue displacements and structural changes of 200 retinal regions of 10 porcine eyes were characterized. Thermal tissue changes were characterized by B-scan images, OCT correlation maps, and tissue displacement maps. Larger tissue deformation was induced with higher laser power and shorter exposure time, while the same total laser energy (10 mJ) was applied. The measured tissue displacements revealed the complicated dynamics of tissue displacements. Three types of dynamics were observed; lateral expansion, lateral constriction, and a type showing more complicated dynamics. The results demonstrated the ability of this OCT-based method to evaluate retinal changes induced by laser irradiation. This evaluation could lead to further understanding of thermal effects, and increasing reproducibility of photocoagulation therapy.

How gamma-rays and electron-beam irradiation would affect the antimicrobial activity of differently processed wild mushroom extracts?

PubMed

Alves, M J; Fernandes, Â; Barreira, J C M; Lourenço, I; Fernandes, D; Moura, A; Ribeiro, A R; Salgado, J; Antonio, A; Ferreira, I C F R

2015-03-01

The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial activity of mushroom species (Boletus edulis, Hydnum repandum, Macrolepiota procera and Russula delica) differently processed (fresh, dried, freeze) were evaluated. Clinical isolates with different resistance profiles from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal, were used as target micro-organisms. The mushrooms antimicrobial activity did not suffer significant changes that might compromise applying irradiation as a possible mushroom conservation technology. Two kGy dose (independently of using gamma-rays or electron-beams) seemed to be the most suitable choice to irradiate mushrooms. This study provides important results in antimicrobial activity of extracts prepared from irradiated mushroom species. © 2014 The Society for Applied Microbiology.

The effect of well-characterized, very low-dose x-ray radiation on fibroblasts

PubMed Central

Truong, Katelyn; Bradley, Suzanne; Baginski, Bryana; Wilson, Joseph R.; Medlin, Donald; Zheng, Leon; Wilson, R. Kevin; Rusin, Matthew; Takacs, Endre

2018-01-01

The purpose of this study is to determine the effects of low-dose radiation on fibroblast cells irradiated by spectrally and dosimetrically well-characterized soft x-rays. To achieve this, a new cell culture x-ray irradiation system was designed. This system generates characteristic fluorescent x-rays to irradiate the cell culture with x-rays of well-defined energies and doses. 3T3 fibroblast cells were cultured in cups with Mylar® surfaces and were irradiated for one hour with characteristic iron (Fe) K x-ray radiation at a dose rate of approximately 550 μGy/hr. Cell proliferation, total protein analysis, flow cytometry, and cell staining were performed on fibroblast cells to determine the various effects caused by the radiation. Irradiated cells demonstrated increased proliferation and protein production compared to control samples. Flow cytometry revealed that a higher percentage of irradiated cells were in the G0/G1 phase of the cell cycle compared to control counterparts, which is consistent with other low-dose studies. Cell staining results suggest that irradiated cells maintained normal cell functions after radiation exposure, as there were no qualitative differences between the images of the control and irradiated samples. The result of this study suggest that low-dose soft x-ray radiation might cause an initial pause, followed by a significant increase, in proliferation. An initial “pause” in cell proliferation could be a protective mechanism of the cells to minimize DNA damage caused by radiation exposure. The new cell irradiation system developed here allows for unprecedented control over the properties of the x-rays given to the cell cultures. This will allow for further studies on various cell types with known spectral distribution and carefully measured doses of radiation, which may help to elucidate the mechanisms behind varied cell responses to low-dose x-rays reported in the literature. PMID:29300773

The Effect of Solar Irradiated Vibrio cholerae on the Secretion of Pro-Inflammatory Cytokines and Chemokines by the JAWS II Dendritic Cell Line In Vitro

PubMed Central

Ssemakalu, Cornelius Cano; Ubomba-Jaswa, Eunice; Motaung, Keolebogile Shirley; Pillay, Michael

2015-01-01

The use of solar irradiation to sterilize water prior to its consumption has resulted in the reduction of water related illnesses in waterborne disease endemic communities worldwide. Currently, research on solar water disinfection (SODIS) has been directed towards understanding the underlying mechanisms through which solar irradiation inactivates the culturability of microorganisms in water, enhancement of the disinfection process, and the health impact of SODIS water consumption. However, the immunological consequences of SODIS water consumption have not been explored. In this study, we investigated the effect that solar irradiated V. cholerae may have had on the secretion of cytokines and chemokines by the JAWS II dendritic cell line in vitro. The JAWS II dendritic cell line was stimulated with the different strains of V. cholerae that had been: (i) prepared in PBS, (ii) inactivated through a combination of heat and chemical, (iii) solar irradiated, and (iv) non-solar irradiated, in bottled water. As controls, LPS (1 μg/ml) and CTB (1 μg/ml) were used as stimulants. After 48 hours of stimulation the tissue culture media from each treatment was qualitatively and quantitatively analysed for the presence of IL-1α, IL-1β, IL-6, IL-7, IL-10, IL-12p40, IL-12p70, IL-15, MIP-1α, MIP-1β, MIP-2, RANTES, TNF-α, IL-23 and IL-27. Results showed that solar irradiated cultures of V. cholerae induced dendritic cells to secrete significant (p<0.05) levels of pro-inflammatory cytokines in comparison to the unstimulated dendritic cells. Furthermore, the amount of pro-inflammatory cytokines secreted by the dendritic cells in response to solar irradiated cultures of V. cholerae was not as high as observed in treatments involving non-solar irradiated cultures of V. cholerae or LPS. Our results suggest that solar irradiated microorganisms are capable of inducing the secretion of pro-inflammatory cytokines and chemokines. This novel finding is key towards understanding the possible immunological consequences of consuming SODIS treated water. PMID:26066787

Speedy fabrication of diameter-controlled Ag nanowires using glycerolunder microwave irradiation conditions

EPA Science Inventory

Diameter-controlled Ag nanowires were rapidly fabricated (1 min) using inexpensive, abundant, and environmentally-friendly glycerol as both reductant and solvent under non-stirred microwave irradiation conditions; no Ag particles were formed using conventional heating methods. Th...

World Market Development and Consumer Acceptance of Irradiation Technology

PubMed Central

Maherani, Behnoush; Hossain, Farah; Criado, Paula; Ben-Fadhel, Yosra; Salmieri, Stephane; Lacroix, Monique

2016-01-01

Food irradiation is an efficient technology that can be used to ensure food safety by eliminating insects and pathogens to prolong the shelf life. The process could be applied to fresh or frozen products without affecting the nutritional value. Presently more than 60 countries have adopted the technology. However, the technology adaptation differs from one country to another and, in some cases, consumers’ misunderstanding and lack of acceptance may hinder the technology adaptation process. This review summarizes the development of irradiation treatment worldwide and consumer attitudes towards the introduction of this technology. Also, the wholesomeness, beneficial effects, and regulation of irradiation are assessed. PMID:28231173

Monitoring of the Irradiated Neutron Fluence in the Neutron Transmutation Doping Process of Hanaro

NASA Astrophysics Data System (ADS)

Kim, Myong-Seop; Park, Sang-Jun

2009-08-01

Neutron transmutation doping (NTD) for silicon is a process of the creation of phosphorus impurities in intrinsic or extrinsic silicon by neutron irradiation to obtain silicon semiconductors with extremely uniform dopant distribution. HANARO has two vertical holes for the NTD, and the irradiation for 5 and 6 inch silicon ingots has been going on at one hole. In order to achieve the accurate neutron fluence corresponding to the target resistivity, the real time neutron flux is monitored by self-powered neutron detectors. After irradiation, the total irradiation fluence is confirmed by measuring the absolute activity of activation detectors. In this work, a neutron fluence monitoring method using zirconium foils with the mass of 10 ~ 50 mg was applied to the NTD process of HANARO. We determined the proportional constant of the relationship between the resistivity of the irradiated silicon and the neutron fluence determined by using zirconium foils. The determined constant for the initially n-type silicon was 3.126 × 1019 n·Ω/cm. It was confirmed that the difference between this empirical value and the theoretical one was only 0.5%. Conclusively, the practical methodology to perform the neutron transmutation doping of silicon was established.

Light ion irradiation for unfavorable soft tissue sarcoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Linstadt, D.; Castro, J.R.; Phillips, T.L.

1990-09-01

Between 1978 and 1989, 32 patients with unfavorable soft tissue sarcoma underwent light ion (helium, neon) irradiation with curative intent at Lawrence Berkeley Laboratory. The tumors were located in the trunk in 22 patients and head and neck in 10. Macroscopic tumor was present in 22 at the time of irradiation. Two patients had tumors apparently induced by previous therapeutic irradiation. Follow-up times for surviving patients ranged from 4 to 121 months (median 27 months). The overall 3-year actuarial local control rate was 62%; the corresponding survival rate was 50%. The 3-year actuarial control rate for patients irradiated with macroscopicmore » tumors was 48%, while none of the patients with microscopic disease developed local recurrence (100%). The corresponding 3-year actuarial survival rates were 40% (macroscopic) and 78% (microscopic). Patients with retroperitoneal sarcoma did notably well; the local control rate and survival rate were 64% and 62%, respectively. Complications were acceptable; there were no radiation related deaths, while two patients (6%) required operations to correct significant radiation-related injuries. These results appear promising compared to those achieved by low -LET irradiation, and suggest that this technique merits further investigation.« less

Near-infrared laser irradiation improves the development of mouse pre-implantation embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yokoo, Masaki; Mori, Miho

The aim of the present study was to assess the effects of near-infrared laser irradiation on the in vitro development of mouse embryos. Female ICR mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin (hCG), and mated with male mice. Two-cell stage embryos were collected 40 h after administering hCG and cultured in M16 medium. Two-cell embryos (0 h after culture), 8-cell embryos (approx. 30 h after culture), morula (approx. 48 h after culture), and blastocysts (approx. 73 h after culture) were irradiated at 904 nm for 60 s. These embryos were cultured in a time-lapse monitoring system and the timing ofmore » blastocyst hatching was evaluated. Some of the irradiated blastocysts were transferred to the uterine horns of pseudopregnant recipients immediately after irradiation. Pregnancy rates, and offspring growth and fertility, were evaluated. Near-infrared laser irradiation increased the speed of in vitro mouse embryo development. In irradiated blastocysts, hatching was faster than in control (non-irradiated) blastocysts (18.4 vs. 28.2 h, P < 0.05). When 195 irradiated blastocysts were transferred to 18 pseudopregnant mice, all became pregnant and 92 (47.2%) normal-looking pups were born alive. When 182 control blastocysts were transferred to 17 pseudopregnant mice, 14 (82.4%) became pregnant and 54 (29.7%) normal-looking pups were born alive. The growth trajectories (up to 5 weeks) of offspring from irradiated blastocysts were similar to those from control blastocysts. Second generation offspring from transplanted animals were all fertile. These results indicate that near-infrared laser irradiation improves the quality of mouse embryo development in vitro, and increases the live birth rate without affecting the normality of the offspring. Thus, the near-infrared laser method may enhance the quality of embryos and contribute to improvements in reproductive technologies in mammals. - Highlights: • Irradiation of blastocysts with a near-infrared laser improves embryo development. • Irradiation of blastocysts increases the live birth rate after embryo transfer. • Irradiation of blastocysts did not affect the normality of the pups. • Near-infrared laser irradiation may be useful to enhance the quality of embryos. • This study may contribute to improvements in reproductive technologies in mammals.« less

Radiation processing of minimally processed vegetables and aromatic plants

NASA Astrophysics Data System (ADS)

Trigo, M. J.; Sousa, M. B.; Sapata, M. M.; Ferreira, A.; Curado, T.; Andrada, L.; Botelho, M. L.; Veloso, M. G.

2009-07-01

Vegetables are an essential part of people's diet all around the world. Due to cultivate techniques and handling after harvest, these products, may contain high microbial load that can cause food borne outbreaks. The irradiation of minimally processed vegetables is an efficient way to reduce the level of microorganisms and to inhibit parasites, helping a safe global trade. Evaluation of the irradiation's effects was carried out in minimal processed vegetables, as coriander ( Coriandrum sativum L .), mint ( Mentha spicata L.), parsley ( Petroselinum crispum Mill, (A.W. Hill)), lettuce ( Lactuca sativa L.) and watercress ( Nasturium officinale L.). The inactivation level of natural microbiota and the D 10 values of Escherichia coli O157:H7 and Listeria innocua in these products were determined. The physical-chemical and sensorial characteristics before and after irradiation at a range of 0.5 up to 2.0 kGy applied doses were also evaluated. No differences were verified in the overall of sensorial and physical properties after irradiation up to 1 kGy, a decrease of natural microbiota was noticed (⩾2 log). Based on the determined D10, the amount of radiation necessary to kill 10 5E. coli and L. innocua was between 0.70 and 1.55 kGy. Shelf life of irradiated coriander, mint and lettuce at 0.5 kGy increased 2, 3 and 4 days, respectively, when compared with non-irradiated.

WE-EF-BRA-10: Prophylactic Cranial Irradiation Reduces the Incidence of Brain Metastasis in a Mouse Model of Metastatic Breast Cancerr

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, D; Debeb, B; Larson, R

Purpose: Prophylactic cranial irradiation (PCI) is a clinical technique used to reduce the incidence of brain metastasis and improve overall survival in select patients with acute lymphoblastic leukemia and small-cell lung cancer. We examined whether PCI could benefit breast cancer patients at high risk of developing brain metastases. Methods: We utilized our mouse model in which 500k green fluorescent protein (GFP)-labeled breast cancer cells injected into the tail vein of SCID/Beige mice resulted in brain metastases in approximately two-thirds of untreated mice. To test the efficacy of PCI, one set of mice was irradiated five days after cell injection withmore » a single fraction of 4-Gy (two 2-Gy opposing fields) whole-brain irradiation on the XRAD 225Cx small-animal irradiator. Four controls were included: a non-irradiated group, a group irradiated two days prior to cell injection, and two groups irradiated 3 or 6 weeks after cell injection. Mice were sacrificed four and eight weeks post-injection and were evaluated for the presence of brain metastases on a fluorescent stereomicroscope. Results: The incidence of brain metastasis in the non-irradiated group was 77% and 90% at four and eight weeks, respectively. The PCI group had a significantly lower incidence, 20% and 30%, whereas the other three control groups had incidence rates similar to the non-treated control (70% to 100%). Further, the number of metastases and the metastatic burden were also significantly lower in the PCI group compared to all other groups. Conclusion: The timing of irradiation to treat subclinical disease is critical, as a small dose of whole-brain irradiation given five days after cell injection abrogated tumor burden by greater than 90%, but had no effect when administered twenty-one days after cell injection. PCI is likely to benefit breast cancer patients at high risk of developing brain metastases and should be strongly considered in the clinic.« less

Near-infrared laser irradiation improves the development of mouse pre-implantation embryos.

PubMed

Yokoo, Masaki; Mori, Miho

2017-05-27

The aim of the present study was to assess the effects of near-infrared laser irradiation on the in vitro development of mouse embryos. Female ICR mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin (hCG), and mated with male mice. Two-cell stage embryos were collected 40 h after administering hCG and cultured in M16 medium. Two-cell embryos (0 h after culture), 8-cell embryos (approx. 30 h after culture), morula (approx. 48 h after culture), and blastocysts (approx. 73 h after culture) were irradiated at 904 nm for 60 s. These embryos were cultured in a time-lapse monitoring system and the timing of blastocyst hatching was evaluated. Some of the irradiated blastocysts were transferred to the uterine horns of pseudopregnant recipients immediately after irradiation. Pregnancy rates, and offspring growth and fertility, were evaluated. Near-infrared laser irradiation increased the speed of in vitro mouse embryo development. In irradiated blastocysts, hatching was faster than in control (non-irradiated) blastocysts (18.4 vs. 28.2 h, P < 0.05). When 195 irradiated blastocysts were transferred to 18 pseudopregnant mice, all became pregnant and 92 (47.2%) normal-looking pups were born alive. When 182 control blastocysts were transferred to 17 pseudopregnant mice, 14 (82.4%) became pregnant and 54 (29.7%) normal-looking pups were born alive. The growth trajectories (up to 5 weeks) of offspring from irradiated blastocysts were similar to those from control blastocysts. Second generation offspring from transplanted animals were all fertile. These results indicate that near-infrared laser irradiation improves the quality of mouse embryo development in vitro, and increases the live birth rate without affecting the normality of the offspring. Thus, the near-infrared laser method may enhance the quality of embryos and contribute to improvements in reproductive technologies in mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of high-frequency near-infrared diode laser irradiation on periodontal tissues during experimental tooth movement in rats.

PubMed

Gunji, Hidemi; Kunimatsu, Ryo; Tsuka, Yuji; Yoshimi, Yuki; Sumi, Keisuke; Awada, Tetsuya; Nakajima, Kengo; Kimura, Aya; Hiraki, Tomoka; Hirose, Naoto; Yanoshita, Makoto; Tanimoto, Kotaro

2018-02-05

Tooth movement during orthodontic treatment is associated with bone neoplasticity and bone resorption on the tension and pressure sides. Previous clinical studies have suggested that low-power laser irradiation can accelerate tooth movement during orthodontic treatment, although the underlying mechanism remains unclear. In this study, we used a high-frequency near-infrared diode laser that generates less heat and examined the histologic changes in periodontal tissue during experimental tooth movement with laser irradiation. A nickel-titanium closed coil was mounted between the maxillary left side first molar and incisor of rats to model experimental tooth movement. The laser-irradiation and the control groups were set, and the amount of movement of the first molar on 7th and 14th days after the start of pulling of the first molar tooth on the maxillary left was measured by three-dimensional analysis of µCT. After tooth movement, tissue samples from the mesial and tension sides were collected, and successive horizontal sections were prepared and examined using hematoxylin-eosin and TRAP staining and immunohistochemical staining for RANKL, OPG, ALP, and proliferating cell nuclear antigen (PCNA). Changes in tissue temperature following laser irradiation were also examined. Laser irradiation significantly increased tooth movement compared with non-irradiated controls. Histologic staining of the pressure-side mesial root in laser-irradiated rats revealed enhanced RANKL expression and increased numbers of TRAP-positive cells compared with controls. By contrast, on the tension side, laser irradiation led to increased expression of ALP and PCNA. These data indicate that high-frequency near-infrared diode laser irradiation on the pressure side upregulates RANKL expression and accelerates osteoclast differentiation, facilitating bone resorption, whereas bone formation is induced on the tension side. This study demonstrates that high-frequency near-infrared diode laser irradiation of periodontal tissue leads to metabolic activation, which ultimately increases the rate of tooth movement. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Nanostructured Solar Irradiation Control Materials for Solar Energy Conversion

NASA Technical Reports Server (NTRS)

Kang, Jinho; Marshall, I. A.; Torrico, M. N.; Taylor, C. R.; Ely, Jeffry; Henderson, Angel Z.; Kim, J.-W.; Sauti, G.; Gibbons, L. J.; Park, C.;

Effects of gamma and electron beam irradiation on the microbial quality of steamed tofu rolls

NASA Astrophysics Data System (ADS)

Jia, Qian; Gao, Meixu; Li, Shurong; Wang, Zhidong

2013-01-01

The effectiveness of two kinds of radiation processing, gamma and electron beam (ebeam) irradiation, for the inactivation of Staphylococcus aureus, Salmonella enteritidis and Listeria innocua which were inoculated in pre-sterilised steamed tofu rolls was studied. The corresponding effects of both irradiation types on total bacterial counts (TBCs) in commercial steamed tofu rolls available in the market were also examined. The microbiological results demonstrated that gamma irradiation yielded D10 values of 0.20, 0.24 and 0.22 kGy for S. aureus, S. enteritidis and L. innocua, respectively. The respective D10 values for ebeam irradiation were 0.31, 0.35 and 0.27 kGy. Gamma and ebeam irradiation yielded D10 values of 0.48 and 0.43 kGy for total bacterial counts in commercial steamed tofu rolls, respectively. The results suggest that ebeam irradiation has similar effect on decreasing TBCs in steamed tofu rolls, and gamma irradiation is slightly more effective than ebeam irradiation in reducing the populations of pathogenic bacteria. The observed differences in D10-values between them might be due to the significant differences in dose rate applied, and radiation processing of soybean products to improve their microbial quality could be available for other sources of protein.

TUBERCULOSIS AND LETHAL AS WELL AS SUBLETHAL WHOLE-BODY X-RAY IRRADIATION OF GUINEA PIGS (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gabler, E.

1964-02-01

Lethally total-body-x-ray-irradiated (550 r) and simultaneously Tb- infected guinea pigs died earlier (1.5 to 3.2 days) than lethally irradiated control animals. A tuberculous focus formation could not be found microscopically or macroscopically in these guinea pigs or in sublethally irradiated and simultaneously infected animals. However, in tubcrculous control animals, which were killed at this time, specific foci could be found in liver, spleen, and lungs. Using sublethal irradiation (300 r) and simultaneous Tb inoculation half of the animals died a radiation death and the rest died of tuberculosis. It was found that 86.4% of the animals die a radiation deathmore » and 13.5% because of tuberculosis when irradiated sublethally 30 days after infection. The greatest tuberculosis foci in these animais appeared in lungs, spleen, and especially in the liver ( destroyed iiver''). Tuberculous giant cells of the Langhans-type were missing in case of irradiation and simultaneous tuberculosis. They appeared again about 20 to 30 days after irradiation. The native resistance to tuberculosis was very reduced in cases of simultaneous exposure; radioinduced cell shortage and cell damage permit tuberculous focus formation only after overcoming the acute radiation syndrome in case of sublethal irradiations. (auth)« less

Irradiation with low-dose gamma ray enhances tolerance to heat stress in Arabidopsis seedlings.

PubMed

Zhang, Liang; Zheng, Fengxia; Qi, Wencai; Wang, Tianqi; Ma, Lingyu; Qiu, Zongbo; Li, Jingyuan

2016-06-01

Gamma irradiation at low doses can stimulate the tolerance to environmental stress in plants. However, the knowledge regarding the mechanisms underlying the enhanced tolerance induced by low-dose gamma irradiation is far from fully understood. In this study, to investigate the physiological and molecular mechanisms of heat stress alleviated by low-dose gamma irradiation, the Arabidopsis seeds were exposed to a range of doses before subjected to heat treatment. Our results showed that 50-Gy gamma irradiation maximally promoted seedling growth in response to heat stress. The production rate of superoxide radical and contents of hydrogen peroxide and malondialdehyde in the seedlings irradiated with 50-Gy dose under heat stress were significantly lower than those of controls. The activities of antioxidant enzymes, glutathione (GSH) content and proline level in the gamma-irradiated seedlings were significantly increased compared with the controls. Furthermore, transcriptional expression analysis of selected genes revealed that some components related to heat tolerance were stimulated by low-dose gamma irradiation under heat shock. Our results suggest that low-dose gamma irradiation can modulate the physiological responses as well as gene expression related to heat tolerance, thus alleviating the stress damage in Arabidopsis seedlings. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigation of Damage with Cluster Ion Beam Irradiation Using HR-RBS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seki, Toshio; Aoki, Takaaki; Matsuo, Jiro

2008-11-03

Cluster ion beam can process targets with shallow damage because of the very low irradiation energy per atom. However, it is needed to investigate the damage with cluster ion beam irradiation, because recent applications demand process targets with ultra low damage. The shallow damage can be investigated from depth profiles of specific species before and after ion irradiation. They can be measured with secondary ion mass spectrometry (SIMS) and Rutherford backscattering spectroscopy (RBS). High resolution Rutherford backscattering spectroscopy (HR-RBS) is a non destructive measurement method and depth profiles can be measured with nano-resolution. The cluster ion beam mixing of thinmore » Ni layer in carbon targets can be investigated with HR-RBS. The mixing depth with cluster ion irradiation at 10 keV was about 10 nm. The mixing depth with cluster ion irradiation at 1 keV and 5 keV were less than 1 nm and 5 nm, respectively. The number of displaced Ni atoms with cluster ion irradiation was very larger than that with monomer ion irradiation of same energy. This result shows that violent mixing occurs with single cluster impact.« less

Pollen and spores as biological recorders of past ultraviolet irradiance

NASA Astrophysics Data System (ADS)

Jardine, Phillip E.; Fraser, Wesley T.; Lomax, Barry H.; Sephton, Mark A.; Shanahan, Timothy M.; Miller, Charlotte S.; Gosling, William D.

2016-12-01

Solar ultraviolet (UV) irradiance is a key driver of climatic and biotic change. Ultraviolet irradiance modulates stratospheric warming and ozone production, and influences the biosphere from ecosystem-level processes through to the largest scale patterns of diversification and extinction. Yet our understanding of ultraviolet irradiance is limited because no method has been validated to reconstruct its flux over timescales relevant to climatic or biotic processes. Here, we show that a recently developed proxy for ultraviolet irradiance based on spore and pollen chemistry can be used over long (105 years) timescales. Firstly we demonstrate that spatial variations in spore and pollen chemistry correlate with known latitudinal solar irradiance gradients. Using this relationship we provide a reconstruction of past changes in solar irradiance based on the pollen record from Lake Bosumtwi in Ghana. As anticipated, variations in the chemistry of grass pollen from the Lake Bosumtwi record show a link to multiple orbital precessional cycles (19-21 thousand years). By providing a unique, local proxy for broad spectrum solar irradiance, the chemical analysis of spores and pollen offers unprecedented opportunities to decouple solar variability, climate and vegetation change through geologic time and a new proxy with which to probe the Earth system.

Early and long-term effects of low- and high-LET radiation on rat behavior and monoamine metabolism in different brain regions

NASA Astrophysics Data System (ADS)

Belov, Oleg

Space radiation is one of the factors representing a significant health risk to the astronauts during deep-space missions. A most harmful component of space radiation beyond the Earth's magnetosphere is the galactic cosmic rays which are composed of high-energy protons, α particles, and high charge and energy (HZE) nuclei. Recent studies performed at particle accelerators have revealed a significant impact of HZE nuclei on the central nervous system and, in particular, on the cognitive functions. However the exact molecular mechanisms behind the observed impairments remain mostly unclear. This research is focused on study of early and long-term effects of low- and high-linear-energy-transfer (LET) radiation on the rat behavior and monoamine metabolism in the brain regions involved in behavior and motor control and form emotional and motivational states. Different groups of rats were whole-body exposed to 500 MeV/u (12) C particles (LET 10.6 keV/µm) available at the Nuclotron accelerator of the Joint Institute for Nuclear Research (Dubna, Russia) and to gamma rays at the equivalent dose of 1 Gy. An additional group of animals was sham-irradiated and considered as a control. The isolated brain regions have included the prefrontal cortex, nucleus accumbens, hypothalamus, hippocampus, and striatum where we determined the concentrations of noradrenalin, dopamine and its metabolites 3,4-doxyphenylacetic acid, homovanillic acid, and 3-methoxytyramine and serotonin and its metabolite 5-hydroxyindoleacetic acid. The following effects were observed in the different periods after irradiation. 1 day after exposure to (12) C particles strong changes in the concentration of monoamines and their metabolites were observed in three structures, namely, the prefrontal cortex, nucleus accumbens, and hippocampus. However, significant changes were found in the prefrontal cortex and weaker changes were seen in the nucleus accumbens, whereas changes were insignificant in the hippocampus. The experiments revealed the high sensitivity and reactivity of the prefrontal cortex, which we relate to the key role of this structure in essential processes of behavior. 30 days after irradiation with (12) C particles and gamma rays behavioral reactions of rats were evaluated by the open field test. The measurements have revealed differences between the effects observed after irradiation with HZE nuclei and gamma-rays at the same dose. The effect of accelerated carbon ions consisted in increasing motion activity measured as the number of sector border crossings and inhibiting exploratory activity of the animals estimated by burrowing, while gamma-irradiation had a significant impact only on the latter index. The rats' total activity increased by 18% after irradiation with (12) C ions, but exposure to gamma rays caused no significant differences from the control values. However the changes in total activity index after sparsely and densely ionizing radiations were also significant. In parallel to the analysis of monoamine metabolism, exploratory behavior, and general activity, some other immunohematological criteria were estimated on the 30th day after exposure to (12) C particles and gamma rays. The significant differences between the HZE-, gamma-irradiated, and control groups were found in the bone marrow cellularity. The changes in spleen mass were significant only between control and each of irradiated group whereas effects of (12) C and gamma rays were near the same. The similar difference was observed for the number of leucocytes in peripheral blood.

[Methods for the rapid preparation of paraffin blocks].

PubMed

Shmurun, R I

1992-01-01

Two accelerated chloroform-paraffin processings of materials with the use of ultrasound (US) and microwave (MW) irradiation in the stove "Electronica" as well as a combined method with US- and MW-irradiation are proposed to shorten drastically the duration of the prehistologic processing.

21 CFR 179.21 - Sources of radiation used for inspection of food, for inspection of packaged food, and for...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sources of radiation used for inspection of food, for inspection of packaged food, and for controlling food processing. 179.21 Section 179.21 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) IRRADIATION IN THE...

Amoeba behavior of UO/sub 2/ coated particle fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner-Loeffler, M.

1977-09-01

The data extracted from numerous irradiation tests were used to derive amoeba endurance parameters for UO/sub 2/. The data do not yet allow an unambiguous definition of the controlling mechanism, which may be due to either gaseous or solid-state diffusion processes. Adequate data on the amoeba effect are available for design of a steam-raising high-temperature gas-cooled reactor using UO/sub 2/ fuel.

Effects of elevated temperatures during interruption of irradiation on Harwell Red 4034 PMMA and Kodak Biomax alanine film dosimetry systems

NASA Astrophysics Data System (ADS)

Sidereas, P.; Patil, D. S.; Garcia, R.; Tracy, R. P.; Holzman, J. M.

2007-11-01

In the industrial setting it is not uncommon for a process interruption to occur during irradiation. In this event, dosimeters may be exposed to prolonged periods of elevated temperature without exposure to ionizing radiation. Once the process is restarted, the same dosimeters are exposed to ionizing radiation in order to achieve target dose. The goal of this experiment was to simulate a process interruption within limits and quantify the effects of a combination of factors (heat, time, and fractionation) on dosimeter response. We present an in-depth experimental study on the response of dosimeters that have been irradiated, stored for a fixed period of time at several temperatures, and then re-irradiated. This study was performed using Harwell Red 4034 polymethylmethacrylate (PMMA) and Kodak BioMax alanine film dosimeters.

Lens of controllable optical field with thin film metallic glasses for UV-LEDs.

PubMed

Pan, C T; Chen, Y C; Lin, Po-Hung; Hsieh, C C; Hsu, F T; Lin, Po-Hsun; Chang, C M; Hsu, J H; Huang, J C

2014-06-16

In the exposure process of photolithography, a free-form lens is designed and fabricated for UV-LED (Ultraviolet Light-Emitting Diode). Thin film metallic glasses (TFMG) are adopted as UV reflection layers to enhance the irradiance and uniformity. The Polydimethylsiloxane (PDMS) with high transmittance is used as the lens material. The 3-D fast printing is attempted to make the mold of the lens. The results show that the average irradiance can be enhanced by 6.5~6.7%, and high uniformity of 85~86% can be obtained. Exposure on commercial thick photoresist using this UV-LED system shows 3~5% dimensional deviation, lower than the 6~8% deviation for commercial mercury lamp system. This current system shows promising potential to replace the conventional mercury exposure systems.

Opto-mechanical system design of test system for near-infrared and visible target

NASA Astrophysics Data System (ADS)

Wang, Chunyan; Zhu, Guodong; Wang, Yuchao

2014-12-01

Guidance precision is the key indexes of the guided weapon shooting. The factors of guidance precision including: information processing precision, control system accuracy, laser irradiation accuracy and so on. The laser irradiation precision is an important factor. This paper aimed at the demand of the precision test of laser irradiator，and developed the laser precision test system. The system consists of modified cassegrain system, the wide range CCD camera, tracking turntable and industrial PC, and makes visible light and near infrared target imaging at the same time with a Near IR camera. Through the analysis of the design results, when it exposures the target of 1000 meters that the system measurement precision is43mm, fully meet the needs of the laser precision test.

Irradiation of municipal sludge for agricultural use

NASA Astrophysics Data System (ADS)

Ahlstrom, Scott B.

Research has demonstrated that irradiation is an effective means for reducing pathogens in sewage sludge to levels where sludge reuse in public areas meets criteria for protection of the public health. Complementary research has demonstrated the value of the irradiated sludge in both agronomic and animal science applications. The benefits of sludge application to cropland are well documented. The irradiation process does not increase the extractability and plant uptake of a broad range of nutrients and heavy metals from sludge-amended soils. However, it does eliminate the hazards associated with pathogen contamination when applying sludge to agricultural land. Irradiated sludge has also been evaluated as a supplemental foodstuff for cattle and sheep. The data indicate that products derived from raw sewage may have a substantial nutritive value for ruminant animals. Irradiation of sewage sludge is a practical means of sludge disinfection. Where a highly disinfected sludge is required, it should be considered as a viable sludge management alternative. Evaluation of sludge irradiation technology and its associated costs must be done with consideration of other sludge treatment processes to develop an acceptable sludge management system.

Guide to solar reference spectra and irradiance models

NASA Astrophysics Data System (ADS)

Tobiska, W. Kent

The international standard for determining solar irradiances was published by the International Standards Organization (ISO) in May 2007. The document, ISO 21348 Space Environment (natural and artificial) - Process for determining solar irradiances, describes the process for representing solar irradiances. We report on the next progression of standards work, i.e., the development of a guide that identifies solar reference spectra and irradiance models for use in engineering design or scientific research. This document will be produced as an AIAA Guideline and ISO Technical Report. It will describe the content of the reference spectra and models, uncertainties and limitations, technical basis, data bases from which the reference spectra and models are formed, publication references, and sources of computer code for reference spectra and solar irradiance models, including those which provide spectrally-resolved lines as well as solar indices and proxies and which are generally recognized in the solar sciences. The document is intended to assist aircraft and space vehicle designers and developers, heliophysicists, geophysicists, aeronomers, meteorologists, and climatologists in understanding available models, comparing sources of data, and interpreting engineering and scientific results based on different solar reference spectra and irradiance models.

Sucrose and color profiles in sugarcane (Saccharum sp.) juice analyzed by UFLC-ELSD and Synapt High-Definition Mass Spectrometry during radiation treatment

NASA Astrophysics Data System (ADS)

Lima, Roberta B.; de Aguiar, Claudio Lima; Galaverna, Renan; Baptista, Antonio S.; Eberlin, Marcos N.; Arthur, Valter

2016-04-01

This work evaluated the effect of electron beam irradiation (E-beam) on sugarcane juice and compared the results with preliminary tests performed on sugarcane juice treated with gamma irradiation. The samples were irradiated at 5, 10 and 20 kGy doses and results were compared wile control samples without irradiation. The results showed a significant increase (p≤0.05) of phenolic compounds in both treatments. We also observed increased contents of reducing sugars (glucose and fructose) for the samples irradiated with gamma rays and E-beam measured by the DNS methods. However, there was no significant difference of sugars content measured by chromatographic analyses performed in the sugarcane juice treated with E-beam. Therefore reducing sugars content could be overestimated by the DNS method because salts in sugarcane juice. The treatments were able to reduce sugarcane juice ICUMSA color intensity in both treatments with irradiation. E-beam reduced sugarcane juice color by roughly 49% compared the control, while gamma irradiation reduced it by 30%.

Effects of laser irradiation on immature olfactory neuroepithelial explants from the rat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mester, A.F.; Snow, J.B. Jr.

1988-07-01

The photobiological effect of low-output laser irradiation on the maturation and regeneration of immature olfactory bipolar receptor cells of the rat was studied. The maturation and regeneration of the receptor cells of rat fetuses were quantified in neuroepithelial explants with morphometric analysis. The number of explants with outgrowth and the number and length of neuritic outgrowths were determined on a regular basis for 12 days. Explants in the experimental group were irradiated with a helium-neon laser using different incident energy densities (IED). Explants in the fluorescent light control group were exposed to fluorescent light for the same periods of timemore » as those in the experimental group were exposed to laser irradiation. Explants in another control group were not exposed to laser or fluorescent light irradiation. The IED of 0.5 J/cm2 laser irradiation has been found to increase significantly the number of explants with outgrowth and the number and length of the outgrowths. Other laser IEDs or fluorescent light irradiation did not influence maturation or regeneration.« less

Development of bioactive coatings based on γ-irradiated proteins to preserve strawberries

NASA Astrophysics Data System (ADS)

Vu, K. D.; Hollingsworth, R. G.; Salmieri, S.; Takala, P. N.; Lacroix, M.

2012-08-01

Gamma irradiation was applied for creating cross-linked proteins to enhance the physicochemical properties of edible films made of calcium caseinate, whey protein isolate and glycerol. The characteristics of γ irradiated cross-linked proteins were analyzed by Fourier Transform Infrared spectroscopy. A second derivative spectra exhibited changes in band intensities that were correlated to an increase of β-sheet structure and a decrease of α-helix and unordered fractions of γ irradiated-cross-linked proteins as compared to the control without irradiation. Furthermore, on addition of methylcellulose to the irradiated protein matrix it was found that it has potential in enhancing the puncture strength and has no detrimental effect on water vapor permeability of protein based films. Finally, these film formulations were used as bioactive edible coatings containing natural antimicrobial agents (limonene and peppermint) to preserve the shelf life of fresh strawberries during storage. The bioactive coatings containing peppermint was found to be more efficient as preserving coatings than the formulations containing limonene. Irradiated proteins/methylcellulose/peppermint formulation had only 40% of decay at day 8 while it was 65% for the control.

Investigating Reflectance Properties of Mercury's Surface Material: Effect of Swift Heavy Ion Irradiation

NASA Astrophysics Data System (ADS)

Carli, C.; Brunetto, R.; Strazzulla, G.; Serventi, G.; Poulet, F.; Capaccioni, F.; Langevin, Y.; Gardes, E.; Martinez, R.; Boduch, P.; Domaracka, A.; Rothard, H.

2018-05-01

Mercury’s surface is affected by space weathering processes, interesting mineral properties. Here, we present a spectral study of swift heavy ion irradiation of two minerals, olivine and nepheline, as a simulation of heavy ion irradiation at Mercury.

Laser biostimulation of wound healing: bioimpedance measurements support histology.

PubMed

Solmaz, Hakan; Dervisoglu, Sergulen; Gulsoy, Murat; Ulgen, Yekta

2016-11-01

Laser biostimulation in medicine has become widespread supporting the idea of therapeutic effects of photobiomodulation in biological tissues. The aim of this study was to investigate the biostimulation effect of laser irradiation on healing of cutaneous skin wounds, in vivo, by means of bioimpedance measurements and histological examinations. Cutaneous skin wounds on rats were subjected to 635 nm diode laser irradiations at two energy densities of 1 and 3 J/cm 2 separately. Changes in the electrical properties of the wound sites were examined with multi-frequency electrical impedance measurements performed on the 3rd, 7th, 10th, and 14th days following the wounding. Tissue samples were both morphologically and histologically examined to determine the relationship between electrical properties and structure of tissues during healing. Laser irradiations of both energy densities stimulated the wound healing process. In particular, laser irradiation of lower energy density had more evidence especially for the first days of healing process. On the 7th day of healing, 3 J/cm 2 laser-irradiated tissues had significantly smaller wound areas compared to non-irradiated wounds (p < 0.05). The electrical impedance results supported the idea of laser biostimulation on healing of cutaneous skin wounds. Thus, bioimpedance measurements may be considered as a non-invasive supplementary method for following the healing process of laser-irradiated tissues.

Morphology-dependent photo-induced polarization recovery in ferroelectric thin films

NASA Astrophysics Data System (ADS)

Wang, J. Y.; Liu, G.; Sando, D.; Nagarajan, V.; Seidel, J.

2017-08-01

We investigate photo-induced ferroelectric domain switching in a series of Pb(Zr0.2Ti0.8)O3/La0.7Sr0.3MnO3 (PZT/LSMO) bilayer thin films with varying surface morphologies by piezoresponse force microscopy under light illumination. We demonstrate that reverse poled ferroelectric regions can be almost fully recovered under laser irradiation of the PZT layer and that the recovery process is dependent on the surface morphology on the nanometer scale. The recovery process is well described by the Kolmogorov-Avrami-Ishibashi model, and the evolution speed is controlled by light intensity, sample thickness, and initial write voltage. Our findings shed light on optical control of the domain structure in ferroelectric thin films with different surface morphologies.

Effects of gamma irradiation dose-rate on sterile male Aedesaegypti

NASA Astrophysics Data System (ADS)

Ernawan, Beni; Tambunan, Usman Sumo Friend; Sugoro, Irawan; Sasmita, Hadian Iman

2017-06-01

Aedesaegypti is the most important vector for dengue, yellow fever and Zika viruses. Considering its medical importance, vector population control program utilizing radiation-based sterile insect technique (SIT) is one of the potential methods for preventing and limiting the dispersal of these viruses. The present study was undertaken to evaluate the dose-rates effects of γ-sterilization on quality parameters of sterile males. Males Ae.aegypti at the pupal stage were sterilized by applying 70 Gyγ-rays in varies dose-rates, i.e. 0 (control), 300, 600, 900, 1200 and 1500Gy/h utilizing panoramic irradiator. Adult males that emerged from the pupal stage were assessed for their quality parameters, which are the percentage of emergence, longevity, sterility and mating competitiveness. The results herein indicate that there was no major effect of dose-rate on the percentage of emergence, the data showedthat there were no differences between irradiated males compared with control. Generally, the longevity of irradiated males was lower compared to control. The data also demonstrated that longevity was significantly increased at the dose-rate from 300 to 900Gy/h, then decreased at the dose-rate 900 to 1500 Gy/h. Sterility of irradiated maleswas significantly different compared to control, while there was no significantly different at dose rate 300 to 1500 Gy/h. Mating competitiveness of irradiated males was increased at the dose rate from 300 to 1200 Gy/h, then the value was decreased significantly at the dose rate 1500 Gy/h. The dose-rate effects of γ-sterilization were discussed in the context genetic vector control, in particular, the SIT. The results give information and contribute to better understanding towards γ-sterilization optimization and quality parameters of sterile male Ae. aegypti on SIT methods.

Which is the best method of sterilization for recycled bone autograft in limb salvage surgery: a radiological, biomechanical and histopathological study in rabbit.

PubMed

Yasin, Nor Faissal; Ajit Singh, Vivek; Saad, Marniza; Omar, Effat

2015-04-15

Limb salvage surgery is a treatment of choice for sarcomas of the extremities. One of the options in skeletal reconstruction after tumour resection is by using a recycled bone autograft. The present accepted methods of recycling bone autografts include autoclaving, pasteurization and irradiation. At the moment there is lack of studies that compare the effectiveness of various sterilization methods used for recycling bone autografts and their effects in terms of bone incorporation. This study was performed to determine the effects of different methods of sterilization on bone autografts in rabbit by radiological, biomechanical and histopathological evaluations. Fresh rabbit cortical bone is harvested from the tibial diaphysis and sterilized extracorporeally by pasteurization (n = 6), autoclaving (n = 6), irradiation (n = 6) and normal saline as control group (n = 6). The cortical bones were immediately reimplanted after the sterilization process. The subsequent process of graft incorporation was examined over a period of 12 weeks by serial radiographs, biomechanical and histopathological evaluations. Statistical analysis (ANOVA) was performed on these results. Significance level (α) and power (β) were set to 0.05 and 0.90, respectively. Radiographic analysis showed that irradiation group has higher score in bony union compared to other sterilization groups (p = 0.041). ANOVA analysis of 'failure stress', 'modulus' and 'strain to failure' demonstrated no significant differences (p = 0.389) between treated and untreated specimens under mechanical loading. In macroscopic histopathological analysis, the irradiated group has the highest percentage of bony union (91.7 percent). However in microscopic analysis of union, the pasteurization group has significantly higher score (p = 0.041) in callus formation, osteocytes percentage and bone marrow cellularity at the end of the study indicating good union potential. This experimental study shown that both irradiation and pasteurization techniques have more favourable outcome in terms of bony union based on radiographic and histopathological evaluations. Autoclaving has the worst outcome. These results indicate that extracorporeal irradiation or pasteurization of bone autografts, are viable option for recycling bone autografts. However, pasteurization has the best overall outcomes because of its osteocytes preservation and bone marrow cellularity.

Ultrasound Irradiation Combined with Hepatocyte Growth Factor Accelerate the Hepatic Differentiation of Human Bone Marrow Mesenchymal Stem Cells.

PubMed

Li, Fan; Liu, Yang; Cai, Yingyu; Li, Xin; Bai, Min; Sun, Ting; Du, Lianfang

2018-05-01

This study investigated the impact of ultrasound (US) irradiation on the hepatic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) induced by hepatocyte growth factor (HGF) and the possible mechanisms. We treated hBMSCs, using HGF with and without US irradiation. Cell viability and stem cell surface markers were analyzed. Hepatocyte-like cell markers and functional markers including α-fetoprotein (αFP/AFP), cytokeratin 18 (CK18), albumin (ALB) and glycogen content were analyzed at the time point of day 1, 3 and 5 after treatment. The involvement of Wnt/β-catenin signaling pathway was evaluated as well. The results showed that the US treatment at 1.0 W/cm 2 or 1.5 W/cm 2 for 30 s or 60 s conditions yielded favorable cell viability and engendered stem cell differentiation. At day 5, the expressions of AFP, CK18, ALB and the glycogen content were significantly elevated in the US-treated group at both messenger ribonucleic acid and protein levels (all p <0.05), in comparison with HGF and control groups. Among all the US treated groups, the expression levels of specific hepatic markers in the (1.5 W/cm 2 for 60 s) group were the highest. Furthermore, Wnt1, β-Catenin, c-Myc and Cyclin D1 were significantly increased after US irradiation (all p <0.05), and the enhancements of c-Myc and Cyclin D1 could be obviously impaired by the inhibitor ICG-001 (p <0.05, p <0.05), in accordance with decreased ALB and CK18 expression and glycogen content (all p <0.05). In conclusion, US irradiation was able to promote the hBMSCs' differentiation mediated by HGF in vitro safely, easily and controllably. The activation of Wnt/β-catenin signaling pathway was involved in this process. US irradiation could serve as a potentially beneficial tool for the research and application of stem cell differentiation. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

Effects of low-level gamma irradiation on the characteristics of fermented pork sausage during storage

NASA Astrophysics Data System (ADS)

Kim, I. S.; Jo, C.; Lee, K. H.; Lee, E. J.; Ahn, D. U.; Kang, S. N.

2012-04-01

The effect of gamma irradiation (0.5, 1, 2, and 4 kGy) on the quality of vacuum-packaged dry fermented sausages during refrigerated storage was evaluated. At Day 0 of irradiation, the pH, redness (CIE a*), yellowness (CIE b*), 2-thiobarbituric acid-reactive substances (TBARS) and volatile basic nitrogen (VBN) values of samples irradiated at 2 and 4 kGy were higher (p<0.05), but the CIE L* values (lightness) were lower than those of the non-irradiated control (p<0.05). At<1 kGy irradiation, however, the pH, CIE L*, CIE a* and CIE b*-value of samples were not significantly influenced by irradiation. The CIE a*, and CIE b*-values of samples irradiated at 2 and 4 kGy decreased with the increase of storage time. The VBN, TBARS, and CIE L*-values of samples irradiated at 4 kGy were not changed significantly during refrigerated storage for 90 days (p>0.05). The total plate counts (TPC) and lactic acid bacteria (LAB) in the samples irradiated at 4 kGy were significantly lower (p<0.01) than those with lower irradiation doses. At the end of storage, the TPC, coliform, and LAB in the samples were not increased after irradiation at 1, 0.5 and 1 kGy, respectively. TPC and LAB were not detected in samples irradiated at 4 kGy at Day 90. In addition, no coliform bacteria were found in samples irradiated at 1 kGy during refrigerated storage. Sensory evaluation indicated that the rancid flavor of samples irradiated at 4 kGy was significantly higher, but aroma and taste scores were lower than those of the control at Day 3 of storage. Irradiation of dry fermented sausages at 2 kGy was the best conditions to prolong the shelf-life and decrease the rancid flavor without significant quality deterioration.

Radioprotective effects of Sipunculus nudus L. polysaccharide combined with WR-2721, rhIL-11 and rhG-CSF on radiation-injured mice

PubMed Central

Jiang, Shuqi; Shen, Xianrong; Liu, Yuming; He, Ying; Jiang, Dingwen; Chen, Wei

2015-01-01

This study investigated the radioprotective effect of Sipunculus nudus L. polysaccharide (SNP) in combination with WR-2721, rhIL-11 and rhG-CSF on irradiated mice. A total of 70 Imprinting Control Region (ICR) mice were divided into seven groups: the control group, the model group and five administration groups. All groups, except the control group, were exposed to a 5 Gy 60Co γ-ray beam. Blood parameters [including white blood cell (WBC), red blood cell (RBC) and platelet counts and hemoglobin level] were assessed three days before irradiation, and the on the 3rd, 7th and 14th days after irradiation. Spleen, thymus and testicular indices, DNA contents of bone marrow cells, bone marrow nucleated cells, sperm counts, superoxide dismutase (SOD), malondialdehyde (MDA), testosterone and estradiol levels in the serum were assessed on the 14th day after irradiation. The combined administration of SNP, WR-2721, rhIL-11 and rhG-CSF exerted synergistic recovery effects on peripheral blood WBC, RBC and platelet counts and hemoglobin levels in irradiated mice, and synergistic promotion effects on spleen, thymus, testicle, bone marrow nucleated cells and sperm counts in irradiated mice. The synergistic administration increased the serum SOD activities and serum testosterone content of irradiated mice, but synergy decreased the content of serum MDA and estradiol in irradiated mice. These results suggest that the combined administration of SNP, WR-2721, rhIL-11 and rhG-CSF should increase the efficacy of these drugs for acute radiation sickness, protect immunity, hematopoiesis and the reproductive organs of irradiated-damaged mice, and improve oxidation resistance in the body. PMID:25852150

Carbon ion radiotherapy performed as re-irradiation using active beam delivery in patients with tumors of the brain, skull base and sacral region.

PubMed

Combs, Stephanie E; Kalbe, Adriana; Nikoghosyan, Anna; Ackermann, Benjamin; Jäkel, Oliver; Haberer, Thomas; Debus, Jürgen

2011-01-01

To asses carbon ion radiation therapy (RT) performed as re-irradiation in 28 patients with recurrent tumors. Twenty-eight patients were treated with carbon ion RT as re-irradiation for recurrent chordoma and chondrosarcoma of the skull base (n=16 and n=2), one chordoma and one chondrosarcoma of the os sacrum, high-risk meningioma (n=3), adenoid-cystic carcinoma (n=4) as well as one SCCHN. All patients were treated using active raster scanning, and treatment planning was performed on CT- and MRI-basis. All patients were followed prospectively during follow-up. In all patients re-irradiation could be applied safely without interruptions. For skull base tumors, local tumor control after re-irradiation was 92% at 24 months and 64% at 36 months. Survival after re-irradiation was 86% at 24 months, and 43% at 60 months. In all three meningiomas treated with C12 for re-irradiation, the tumor recurrence was located within the former RT-field. Two patients developed tumor progression at 6 months, and in one patient the tumor remained stable for 67 months. In patients with head-and-neck tumors, three patients developed local tumor progression at 12, 24 and 29 months after re-irradiation. Median local progression-free survival was 24 months. For sacral tumors, re-irradiation offered palliation with tumor control for 24 and 36 months. Due to the physical characteristics particle therapy offers a new treatment modality in cases with tumor recurrences. With carbon ions, the additional biological benefits may be exploited for long-term tumor control. Further evaluation in a larger patients' cohort will be performed in the future. Copyright © 2010. Published by Elsevier Ireland Ltd.

Platelet-activating factor receptor agonists mediate xeroderma pigmentosum A photosensitivity.

PubMed

Yao, Yongxue; Harrison, Kathleen A; Al-Hassani, Mohammed; Murphy, Robert C; Rezania, Samin; Konger, Raymond L; Travers, Jeffrey B

2012-03-16

To date, oxidized glycerophosphocholines (Ox-GPCs) with platelet-activating factor (PAF) activity produced non-enzymatically have not been definitively demonstrated to mediate any known disease processes. Here we provide evidence that these Ox-GPCs play a pivotal role in the photosensitivity associated with the deficiency of the DNA repair protein xeroderma pigmentosum type A (XPA). It should be noted that XPA-deficient cells are known to have decreased antioxidant defenses. These studies demonstrate that treatment of human XPA-deficient fibroblasts with the pro-oxidative stressor ultraviolet B (UVB) radiation resulted in increased reactive oxygen species and PAF receptor (PAF-R) agonistic activity in comparison with gene-corrected cells. The UVB irradiation-generated PAF-R agonists were inhibited by antioxidants. UVB irradiation of XPA-deficient (Xpa-/-) mice also resulted in increased PAF-R agonistic activity and skin inflammation in comparison with control mice. The increased UVB irradiation-mediated skin inflammation and TNF-α production in Xpa-/- mice were blocked by systemic antioxidants and by PAF-R antagonists. Structural characterization of PAF-R-stimulating activity in UVB-irradiated XPA-deficient fibroblasts using mass spectrometry revealed increased levels of sn-2 short-chain Ox-GPCs along with native PAF. These studies support a critical role for PAF-R agonistic Ox-GPCs in the pathophysiology of XPA photosensitivity.

Molecular DNA-based detection of ionising radiation in meat.

PubMed

Şakalar, Ergün

2017-05-01

Ionising radiation induces molecular alterations, such as formation of ions, free radicals, and new stable molecules, and cleavage of the chemical bonds of the molecules present in food. Irradiation-treated meat should be labelled to control the process and to ensure free consumer choice. Therefore, sensitive analytical methods are required to detect the irradiation dose. Meat samples were exposed to radiation doses of 0, 0.272, 0.497, 1.063, 3.64, 8.82 and 17.42 kGy in an industrial 60 Co gamma cell. Primers were designed to amplify 998, 498 and 250-base pair (bp) regions of the 18S rRNA gene of nuclear DNA from the irradiated samples. A new DNA-based method was developed to quantify the radiation exposed to the unstored meat and the meat stored at -20 °C for 3 and 6 months. The method was able to detect meat samples stored and unstored with dose limits of 1.063 and 3.64 kGy, respectively. The level of irradiation can be detected using primer pairs that target particularly different-sized sequences for DNA amplification by PCR. This method can be widely used for the analysis of not only meat samples, but also all biological materials containing DNA. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Lithium delays the radiation-induced apoptotic process in external granule cells of mouse cerebellum.

PubMed

Inouye, M; Yamamura, H; Nakano, A

1995-09-01

Proliferating cells of the external granular layer (EGL) in the developing cerebellum are highly sensitive to ionizing radiation. We examined the effect of lithium, an inhibitor of intracellular signaling, on the manifestation of radiation-induced apoptosis. Newborn mice were exposed to 0.5 Gy gamma-irradiation alone, or first were treated with lithium (10 mumol/g, SC) then given 0.5 Gy irradiation 2 hr later. The EGL was examined histologically for apoptosis at various times after treatment. Apoptotic cells increased rapidly, peaked (about 14%) 6 hr after irradiation, then decreased gradually to the control level by 24 hr. Prior treatment with lithium delayed the manifestation of apoptosis, the peak appearing at 12 hr. The disappearance of dead cells was delayed for about one day. The lithium concentration in the whole brain increased rapidly, being 30 micrograms/g at the time of irradiation and remaining at more than 40 micrograms/g for 40 hr. Lithium is reported to inhibit guanine-nucleotide binding to G proteins as well as phosphoinositide turnover. Of the variety of lesions induced by radiation, DNA double strand breaks are the most important source of cell lethality. The present findings, however, suggest that cyclic AMP-mediated and/or phosphoinositidemediated signaling systems regulate radiation-induced apoptosis.

An automated flow system incorporating in-line acid dissolution of bismuth metal from a cyclotron irradiated target assembly for use in the isolation of astatine-211

DOE Office of Scientific and Technical Information (OSTI.GOV)

O’Hara, Matthew J.; Krzysko, Anthony J.; Niver, Cynthia M.

Astatine-211 (211At) is a promising cyclotron-produced radionuclide being investigated for use in targeted alpha therapy of blood borne and metastatic cancers, as well as treatment of tumor remnants after surgical resections. The isolation of trace quantities of 211At, produced within several grams of a Bi metal cyclotron target, involves a complex, multi-step procedure: (1) Bi metal dissolution in strong HNO3, (2) distillation of the HNO3 to yield Bi salts containing 211At, (3) dissolution of the salts in strong HCl, (4) solvent extraction of 211At from bismuth salts with diisopropyl ether (DIPE), and (5) back-extraction of 211At from DIPE into NaOH,more » leading to a purified 211At product. Step (1) has been addressed first to begin the process of automating the onerous 211At isolation process. A computer-controlled Bi target dissolution system has been designed. The system performs in-line dissolution of Bi metal from the target assembly using an enclosed target dissolution block, routing the resulting solubilized 211At/Bi mixture to the subsequent process step. The primary parameters involved in Bi metal solubilization (HNO3 concentration and influent flow rate) were optimized prior to evaluation of the system performance on replicate cyclotron irradiated targets. The results indicate that the system performs reproducibly, having nearly quantitative release of 211At from irradiated targets, with cumulative 211At recoveries that follow a sigmoidal function. The predictable nature of the 211At release profile allows the user to tune the system to meet target processing requirements.« less

Effectiveness of a new method of disinfecting the root canal, using Er, Cr:YSGG laser to kill Enterococcus faecalis in an infected tooth model.

PubMed

Licata, M E; Albanese, A; Campisi, G; Geraci, D M; Russo, R; Gallina, G

2015-02-01

Some lasers have demonstrated to provide effective disinfection when used as adjunctive device to the conventional treatment. The aim of this in vitro study was to determine the effectiveness of the erbium, chromium:yttrium scandium gallium garnet (Er, Cr:YSGG) laser by measuring its bactericidal effect inside the root canal experimentally colonized with Enterococcus faecalis. The laser was tested at different irradiation times (30 and 60 s) and energy of impulses (75 and 25 mJ). A total of 52 single-rooted extracted human teeth were endodontically prepared with rotary instrumentation. All were sterilized and inoculated with a suspension of E. faecalis (105 bacteria/ml). The teeth were randomized into three treatment (group 1, group 2, and group 3) and one control groups. In all groups, teeth were chemically irrigated with 5.25% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Groups 1 and 2 were also irradiated at 30 and 60 s, respectively, with an Er, Cr:YSGG laser at 75 mJ. Teeth of group 3 were treated with laser for 60 s at 25 mJ. Samples were processed to detect the presence of E. faecalis. For all groups, a bactericidal effect was observed. The use of laser at 75 mJ with an irradiation time of 30 and 60 s eliminated a percentage of 92.3 and 100% of E. faecalis, respectively. In the control group, a reduction of 92.3% was observed. Lower percentage of reduction (46.1%) was obtained in teeth treated with laser at 25 mJ for 60 s. No statistical differences were observed between the groups (P = 0.543, Fisher's exact test). The results indicated a bactericidal effect of Er, Cr:YSGG laser irradiation at the settings used in this study. The highest bactericidal effect of this laser was observed at 60 s of irradiation time, using an energy pulse of 75 mJ.

Morphological alterations of periodontal pocket epithelium following Nd:YAG laser irradiation.

PubMed

Ting, Chun-Chan; Fukuda, Mitsuo; Watanabe, Tomohisa; Sanaoka, Atsushi; Mitani, Akio; Noguchi, Toshihide

2014-12-01

The purpose of this in vivo study was to examine morphologic alterations in the periodontal pocket epithelium with presence or absence of clinical inflammation following the use of the Neodymium: Yttrium-Aluminum-Garnet (Nd:YAG) laser irradiation. Subgingival Nd:YAG laser irradiation has been proposed as an alternative technique for treatment of chronic periodontitis. Several published studies have reported the clinical outcomes of such treatment. Twenty patients, diagnosed with moderate chronic periodontitis, were selected for the study. A total of 32 sites was identified and divided into a control (n=18) and laser-treated test groups (n=14). Probing depth (PD) and bleeding on probing (BOP) were recorded for all sites. Test sites were irradiated with an Nd:YAG laser using parameters of 2 W, 200 mJ pulse energy, and 10 pps delivered through a 320 μm diameter tip. Total laser treatment time ranged from 1 to 2 min. Following treatment, all specimens were harvested via biopsy and processed for scanning electron microscopy (SEM) and histologic examination. Control group specimens, depending upon initial PD, exhibited either a relatively smooth and intact epithelium with little desquamation (PD≤3 mm), or increasing degrees of epithelial desquamation and leukocytic infiltration at a PD of ≥4 mm. In the laser-treated test group, the specimens with PD≤3 mm that were BOP negative (-) exhibited a thin layer of epithelium that was disrupted. In the specimens with initial PD of ≥4 mm, complete removal of the epithelium whose extent and degree were increasing, was observed in the inflamed portion, while epithelium remained in the uninflamed portion. The SEM and histologic findings demonstrated the feasibility of ablating pocket epithelium with an Nd:YAG laser irradiation using parameters of 2 W of power (200 mJ, 10 pps). Furthermore, the presence or absence of clinical inflammation appeared to have an impact on the degree of laser-mediated epithelial ablation.

Irradiation of shell egg on the physicochemical and functional properties of liquid egg white.

PubMed

Min, B; Nam, K C; Jo, C; Ahn, D U

2012-10-01

This study was aimed at determining the effect of irradiation of shell eggs on the physiochemical and functional properties of liquid egg white during storage. Color and textural parameters of irradiated liquid egg white after cooking were also determined. Shell eggs were irradiated at 0, 2.5, 5, or 10 kGy using a linear accelerator. Egg white was separated from yolk and stored in at 4°C up to 14 d. Viscosity, pH, turbidity, foaming properties, color, and volatile profile of liquid egg white, and color and texture properties of cooked egg white were determined at 0, 7, and 14 d of storage. Irradiation increased the turbidity but decreased viscosity of liquid egg white. Foaming capacity and foam stability were not affected by irradiation at lower dose (2.5 kGy), but were deteriorated at higher doses (≥5.0 kGy) of irradiation. Sulfur-containing volatiles were generated by irradiation and their amounts increased as the irradiation dose increased. However, the sulfur volatiles disappeared during storage under aerobic conditions. Lightness (L* value) and yellowness (b* value) decreased, but greenness (-a* value) increased in cooked egg white in irradiation dose-dependent manners. All textural parameters (hardness, adhesiveness, cohesiveness, chewiness, and resilience) of cooked egg white increased as the irradiation dose increased, but those changes were marginal. Our results indicated that irradiation of shell egg at lower doses (up to 2.5 kGy) had little negative impact on the physiochemical and functional properties of liquid egg white, but can improve the efficiency of egg processing due to its viscosity-lowering effect. Therefore, irradiation of shell eggs at the lower doses has high potential to be used by the egg processing industry to improve the safety of liquid egg without compromising its quality.

The role of fluoride and chlorhexidine in preserving hardness and mineralization of enamel and cementum after gamma irradiation.

PubMed

Abdalla, Rowida; Niazy, Maha A; Jamil, Wael E; Hazzaa, Hala A; Elbatouti, Amal A

2017-05-01

The purpose of this study was to evaluate the effect of 0.05% sodium fluoride and 0.12% chlorhexidine mouthwashes on the micro-hardness of tooth enamel and cementum that was exposed to therapeutic doses of gamma radiation. Sixty extracted human teeth were divided into two groups, one was irradiated, the other was not irradiated. The two groups were further subdivided into three subgroups, which were each treated either with 0.05% sodium fluoride or with 0.12% chlorhexidine; the third subgroup served as a control. After demineralization-remineralization cycling, teeth from the irradiated groups showed a significantly lower micro-hardness when compared to those from the non-irradiated groups. Both in the irradiated and non-irradiated groups, teeth from the control subgroups showed a significantly lower micro-hardness, as compared to teeth treated with sodium fluoride and chlorhexidine. For non-irradiated enamel samples, those treated with chlorhexidine showed a significantly less micro-hardness compared to those treated with sodium fluoride. In contrast, irradiated enamel showed no significant difference in micro-hardness, whatever treatment (chlorhexidine or sodium fluoride) was applied. For cementum, treatment with chlorhexidine resulted in a significantly lower micro-hardness compared to sodium fluoride, both for the irradiated and non-irradiated groups. It is concluded that gamma irradiation with therapeutic doses typically used for head and neck carcinoma treatment has a direct effect in reducing micro-hardness of tooth enamel and cementum. Mouthwash protocols including, for example, application of 0.05% sodium fluoride or 0.12% chlorhexidine three times per day for 6 weeks, can protect enamel and cementum against the reduction in hardness and demineralization caused by gamma irradiation. Sodium fluoride offers more protection compared to chlorhexidine.

The effects of food irradiation on quality of pine nut kernels

NASA Astrophysics Data System (ADS)

Gölge, Evren; Ova, Gülden

2008-03-01

Pine nuts ( Pinus pinae) undergo gamma irradiation process with the doses 0.5, 1.0, 3.0, and 5.0 kGy. The changes in chemical, physical and sensory attributes were observed in the following 3 months of storage period. The data obtained from the experiments showed the peroxide values of the pine nut kernels increased proportionally to the dose. On contrary, irradiation process has no effect on the physical quality such as texture and color, fatty acid composition and sensory attributes.

Effect of /sup 60/Co. gamma. radiation on hexobarbital-induced sleeping times in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brady, M.E.; Hayton, W.L.

1977-03-01

The duration of the loss of righting reflex (sleeping time) was determined after intraperitoneal administration of 100 mg(/kg hexobarbital to adult male Sprague--Dawley rats that were exposed to /sup 60/Co ..gamma.. radiation or sham irradiated. No difference between irradiated and control animals was detected at 1, 3, 5, and 7 days after 850 R. Also, no difference between irradiated and control animals was detected at 5 days after 1000 or 1400 R.