γ-射线照射对于麦芽及大麦制麦质量的影响

采用一种６０钴（６０Ｃｏ）源在两种不同照射剂量范围（０．０５～０．７５ＫＧＹ和０．５～５．０ＫＧＹ），对两种二棱大麦品种Ｔｏｋａｋ和Ｃｌｅｒｉｎｅ进行照射。在制麦前的大麦用中等剂量水平照射时，对于大部分麦芽质量标准产生不利的影响，照射剂量达到０．２５ＫＧＹ时的不利影响较小。然而，照射麦芽样品时仅产生轻微的或者没有质量性质的变化。

^(60)Co γ-射线诱导人膀胱癌EJ细胞中磷酸化组蛋白H2AX焦点形成

目的探讨60Co γ-射线是否可在人膀胱癌EJ细胞中诱导磷酸化组蛋白H2AX焦点形成以及形成的焦点数量与照射剂量及照射后时间的关系。方法免疫印迹法和流式细胞分析法用于检测不同剂量60Co γ-射线照射后EJ细胞中γH2AX蛋白表达的变化;免疫荧光法检测不同剂量照射后以及2 Gy照射后不同时间EJ细胞中γH2AX焦点的数量。结果γ-射线照射后γH2AX蛋白表达明显增加,但量效关系不明显;免疫荧光法可检测γH2AX焦点形成的数量和大小,并且存在剂量-效应关系及有时间依赖性,随着照射剂量的增加,γH2AX焦点数目及大小均明显增加,照射的剂量范围从0.1~4.0 Gy均可检测,照射后24 h仍可检测到γH2AX焦点,但焦点数随时间延长而减少、减弱。结论免疫荧光法检测照射后γH2AX焦点数目可敏感、直观地反映DNA损伤及修复情况,有望成为辐射检测及辐射致癌的好的生物指标。

Radiation-induced attenuation self-compensating effect in super-fluorescent fiber source

The compact super-fluorescent fiber source(SFS) output spectra variations at different pump currents and under different dose of gamma-ray radiation were measured and compared respectively. The radiation-induced attenuation(RIA)self-compensating effect in SFS based on photo-bleaching was found and the general mathematic model of SFS output spectra variations was made. The radiation-induced background attenuation(RIBA) at the pump wavelength was identified to be the main cause of the total output power and spectra variations and the variations can then be compensated by active control of the pump power to enhance the self-compensating effect. With closed-loop feedback control of pump current,double-pass backward(DPB) configuration and spectrum re-shaping technology, an SFS prototype was made and tested.The mean-wavelength stability of about 87.4 ppm and output power instability of less than 5% were achieved under up to200 krad(Si) gamma-ray irradiation.

Impact of substrate bias on radiation-induced edge effects in MOSFETs

This paper investigates the effects of gamma-ray irradiation on the Shallow-Trench Isolation (STI) leakage currents in 180-nm complementary metal oxide semiconductor technology.No hump effect in the subthreshold region is observed after irradiation,which is considered to be due to the thin STI corner oxide thickness.A negative substrate bias could effectively suppress the STI leakage,but it also impairs the device characteristics.The three-dimensional simulation is introduced to understand the impact of substrate bias.Moreover,we propose a simple method for extracting the best substrate bias value,which not only eliminates the STI leakage but also has the least impact on the device characteristics.

复方黄芪口服液对放射小鼠细胞周期及免疫功能的影响

目的 :探讨复方黄芪口服液对放射小鼠细胞周期及免疫功能的影响。方法 :应用流式细胞仪 (FCM)检测脾脏细胞周期和免疫参数 (NK、CD4 +、CD8+)。结果 :该复方中药能使受照小鼠脾细胞S、G2 +M期的比例升高 ,促进脾细胞增殖 ,并能提高NK细胞活性和CD4 +百分率及CD4 +/CD8+比值。结论

复方中药在受照小鼠中抗放射及抗菌群失调的作用研究

目的研究复方中药对受照小鼠的生物学效应及菌群变化。方法采取灌胃方法给药,60Co-γ射线一次性照射。结果复方中药能提高受照小鼠30 d的存活率,并能增加白细胞数量和降低微核率的功能。还能增加生理性细菌的数量,防止菌群失调。结论复方中药对受照小鼠有一定的辐射防护作用。

Preparation and utilization of phosphate biofertilizers using agricultural waste

In this study, Aspergillus niger 1107 was isolated and identified as an efficient phosphate-solubilizing fungus(PSF). This strain generated 689 mg soluble P L–1 NBRIP medium after 10 d of culture. To produce an affordable biofertilizer using A. niger 1107, the potential of widely available carrier materials for growth and maintenance of this strain were evaluated. The effects of sterilization procedures(autoclaving and gamma-ray irradiation) on the suitability of these carriers to maintain growth of the fungus were also investigated. The carrier materials were peat, corn cobs with 20%(w/w) perlite(CCP), wheat husks with 20%(w/w) perlite(WHP), and composted cattle manure with 20%(w/w) perlite(CCMP). In the first 5-6 mon of storage, the carriers sterilized by gamma-ray irradiation maintained higher inoculum loads than those in carriers sterilized by autoclaving. However, this effect was not detectable after 7 mon of storage. For the P-biofertilizer on WHP, more than 2.0×107 viable spores of A. niger g–1 inoculant survived after 7 mon of storage. When this biofertilizer was applied to Chinese cabbage in a pot experiment, there were 5.6×106 spores of A. niger g–1 soil before plant harvesting. In the pot experiment, Chinese cabbage plants grown in soil treated with peat- and WHP-based P-biofertilizers showed significantly greater growth(P<0.05) than that of plants grown in soil treated with free-cell biofertilizer or the CCMP-based biofertilizer. Also, the peat- and WHP-based P-biofertilizers increased the available P content in soil.

Identification of Two Novel Mitochondrial DNA Deletions Induced by Ionizing Radiation

Objective We identify ionizing radiation-induced mitochondrial DNA (mtDNA) deletions in human lymphocytes and their distribution in normal populations. Methods Long-range polymerase chain reactions (PCR) using two pairs of primers specific for the human mitochondrial genome were used to analyze the lymphoblastoid cell line following exposure to 10 Gy 60 Co γ-rays. Limited-condition PCR, cloning and sequencing techniques were applied to verify the mtDNA deletions detected with long-range PCR. Human peripheral blood samples were irradiated with 0, 2 and 6 Gy 60 Co γ-rays, and real-time PCR analysis was performed to validate the mtDNA deletions. In order to know the distribution of mtDNA deletions in normal population, 222 healthy Chinese adults were also investigated. Results Two mtDNA deletions, a 7455-bp deletion (nt475-nt7929 in heavy strand) and a 9225-bp deletion (nt7714 -nt369 in heavy strand), occurring between two 8-bp direct repeats, were identified in lymphoblastoid cells using long-range PCR, limited-condition PCR and sequencing. These results were also observed for 60 Co γ-rays irradiated human peripheral blood cells. Conclusion Two novel mtDNA deletions, a 7455-bp deletion and a 9225-bp deletion, were induced by ionizing radiation. The rate of the mtDNA deletions within a normal population was related to the donors' age, but was independent of gender.

含有特定乙丙共聚物、胺类光稳定剂和非酚类抗氧剂的耐γ-射线乙丙共聚物树脂组成物

韩国专利KR2005，0053937A 目的：提供一种耐γ-射线的乙烯-丙烯共聚物树脂组成物，在γ-射线照射后不至于破坏，适用于放射线灭菌的医疗器械材料。组成：乙丙共聚物树脂组成物包含95—99．7wt％的乙烯-丙烯共聚物（230℃下熔流指数为0．1～20g／10min）、0．5～50wt％的乙烯、0．01～1wt％的胺类光稳定剂和0．01～1wt％的非酚类抗氧化剂。