Low-dose irradiation

In low-dose irradiated [83-86] or fuming nitric acid treated PE [87,88], hexagonal phases can be observed at low temperature and pressure. 

The use of ionizing irradiation on fruits and vegetables has not been intensively studied, but a few experiments have suggested that irradiation has potential for such an application (Allende et al., 2006 Zhang et al., 2006). Results from Buchanan et al. (1998) indicated that low-dose irradiation could easily eliminate E. coli 0157 H7 from fresh apple juice, but they also showed that acid-adapted strains needed higher doses of irradiation in order to obtain a 5 D inactivation in juice (73-value decimal reduction time, i.e. the amount of time it takes at a certain temperature to kill 90% of the organisms being studied (Wikipedia, 2006)). In experiments where sprouts were irradiated... 

Appreciable delay of ripening and consequent enhancement of shelf life have been noted in some tropical fruits such as bananas, plantain, and mangoes after low-dose irradiation (0.2-0.7 kGy) [40,41]. Maximum delay of ripening has been observed with fruits of lower maturity. However, these feasible levels of doses are close to those that induce phytotoxicity, and many factors (varietal differences, the fruit s stage of maturity at the time of irradiation, etc.) make the outcome of the treatment uncertain. 

Mild heat treatment such as a hot water dip in combination with low-dose irradiation found to be efficient to decrease rot and without adverse effect on nonmicrobial qualities of certain fruits such as mangoes [110,111] and clementines [112]. 

Gokmen, V., Akbudak, B., Serpen, A. (2007). Effects of controlled atmosphere storage and low-dose irradiation on potato tuber components affecting acrylamide and color formations upon frying. European Food Research and Technology, 224, 681-687. 

It was ultimately concluded that low-dose gamma irradiation of fresh shrimp reduced melanosis and resulted in a significant extension of their iced-storage life. However, if shrimp were held beyond the onset of melanogenesis, subsequent low-dose irradiation accelerated blackspot formation, which reduced consumer appeal, and therefore was definitely undesirable (3,13). 

Waksman R, Robinson KA, Crocker IR, et al. Endovascular low-dose irradiation inhibits neointima formation after coronary artery balloon injury in swine a possible role for radiation therapy in restenosis prevention. Circulation 1995 91 1533-1539. 

The effect of low-dose irradiation of the immune system was investigated in mice (Ren et al, 2006). When a 0.2 Gy (20 rad) dose of x-irradiation was administered every other day for a total of four times, the number of lymphocytes yielded by the liver, spleen, and thymus decreased by 10 days, but increased above the level of the control mice by day 28. The population of NK cells dramatically expanded, especially in the liver where primordial lymphocytes were present. Functional and phenotypic activation of these cells occurred at the recovery stage, raising the possibility that an initial activation of macrophages by low-dose irradiation mediated the innate immune system (Ren et al., 2006). 

Thus, it would appear that low dose irradiation is fully capable of inducing adaptive responses so that the overall response is below that when the adaptive response was not induced. Advocates of hormesis suggest that we may be ignoring the benefits of radiation hormesis (the low level that produces adaptation necessary to combat higher levels of radiation) if we set our allowable radiation limits too high. The next study addresses this concept. 

As it was shown above, the static kinetics of tunnelling luminescence is much simpler than the diffusion-controlled kinetics. The static tunnelling luminescence intensity often obeys the empirical Becquerel s law [87] I t) oc t ° , where the distinctive decay parameter a = —d ogI i)/ d ogt) is defined by the spatial distribution of defects only, usually considered to be either the isolated pairs of spatially well-correlated dissimilar defects (low dose irradiation) or the random mixture of dissimilar defects (high doses and/or high temperatures) [88]. Moreover, in the case of pairwise distribution, the partial lightsum method has been presented [88-91] in order to restorate the defect initial spatial distribution /(r) within geminate pairs -see equation (4.2.1) and below. What we have discussed here are the tran-... 

ESR spectroscopy, on the other hand, is much more sensitive and may be also used for the analysis of low-dose irradiation products. It yields details about the defect structure around an impurity atom and the chemical nature of its neighbors. The only drawback of the method is the difficulty in interpreting the ESR spectra unambiguously . ... 

Despite years of research on irradiation odor, many questions remain unanswered. There is no systematic descriptive sensory analysis of irradiation-induced odor and aroma in RTE meat products. The description of off-odor has been mostly reported for raw meats. Limited studies have indicated that the off-odor is not always found in low dose irradiation-induced RTE products. The descriptive analysis may be conducted on RTE products irradiated in higher doses, so distinguished odors can be detected. 

Kohler, F., Cardon, G., Pohlman, M., Gill, R., Schider, O. 1989. Enhancement of transformation rates in higher plants by low-dose irradiation are DNA repair systems involved in incorporation of exogenous DNA into the plant genome Plant Mol Biol 12 189-199. 

Influence of low dose irradiation on the reactor fixed internals. 

Whether Cu CVD or electroless Cu deposition, the result is a three-step process, as illustrated in Fig. 6, for patterned, adherent deposition of Cu on PTFE. Step one is patterned low-dose irradiation of PTFE with cither... 

Low-dose irradiation with 50 cGy of X-ray induced in vivo production of superoxide dismutase-like substances and accelerated antioxidant activity in liver, brain and bone marrow of male C57BL/6 mice (Yamaoka et al. 1999). 

Pai, H.H. Yang, M.G. Yang, J.S. Chen, E.R. Liu, M.S. Low dose irradiation of snail and fish for parasite control. Research Rep. No. 561. Food Industry Research and Development Institute, Hsinchu, Taiwan, ROC (in Chinese), 1989. 

For the irradiation itself, the sample is packed in polyethylene vials for total neutron doses of less than 10 cm and in high-purity quartz ampoules for longer irradiations at higher fluxes. The packed samples are transferred to the reactor in containers (rabbits) of aluminum, polyamide, graphite, or high-pressure polyehtylene for low-dose irradiation. 

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