SRAP Marker Analysis of Genomic Mutation Induced by ^(60)Coγ-Ray Irradiation in Potato (Solanum tuberosum)

[Objective] This study was to explore the mutagenic effect of 60Co γ-ray on Solanum tuberosum chromosomes.[Method] The 60Co γ-ray at different irradiation doses was applied to treat the minitubers of potato variety ＇Favorita＇,and the genomic mutations in VM1 and VM2 gene rations in treatments with different doses were analyzed by SRAP markers.[Resalt] Thirty pairs of SRAP primers out of 88 pairs exhibited polymorphism with a rate of 34.1％ in the bulked selection of VM1 generation.A total of 225 bands were obtained,of which 64 were polymorphic with a rate of 28.4％.The polymorphism was reflected in the forms of deleted bands and added bands.Based on the result of the bulked selection of VM1 generation,25 primers with polymorphism were selected to scan VM2 generation.Five primers performed poorly,and nine of the rest 20 pairs revealed polymorphism and obtained nine polymorphic bands,of which only four bands were detected in VM1 generation and the other five ones were newly deleted bands.Only 9.8％ of the bands detected in VM1 generation were obtained in VM2 generation.Eventually,nine stable and dear polymorphic bands were recovered and cloned,and DNA sequences of six bands of them were acquired by sequencing.According to the comparative analysis,five fragments sequences were similar to potato chromosome with a similarity rate of 77％-89％,three of them located at the resistance gene cluster; another one fragment had a similarity of 93％ with some regions of the No.5 chromosome in tomato.[Conclusion] 60Co γ-ray irradiation can cause mutation of genomic DNA in potato;there is no significant correlation between the number of polymorphic bands and the irradiation dose; potymorphic bands are characterized by a larger number of deleted bands than that of the added ones.

Study on Color Information Degradation Induced byγ-ray Radiation in CMOS Cameras

Theγ-rays are widely and abundantly present in strong nuclear radiation environments,and when they act on the camera equipment used to obtain environmental visual information on nuclear robots,radiation effects will occur,which will degrade the performance of the camera system,reduce the imaging quality,and even cause catastrophic consequences.Color reducibility is an important index for evaluating the imaging quality of color camera,but its degradation mechanism in a nuclear radiation environment is still unclear.In this paper,theγ-ray irradiation experiments of CMOS cameras were carried out to analyse the degradation law of the camera’s color reducibility with cumulative irradiation and reveal the degradation mechanism of the color information of the CMOS camera underγ-ray irradiation.The results show that the spectral response of CMOS image sensor(CIS)and the spectral transmittance of lens after irradiation affect the values of a^(*)and b^(*)in the LAB color model.While the full well capacity(FWC)of CIS and transmittance of lens affect the value of L^(*)in the LAB color model,thus increase color difference and reduce brightness,the combined effect of color difference and brightness degradation will reduce the color reducibility of CMOS cameras.Therefore,the degradation of the color information of the CMOS camera afterγ-ray irradiation mainly comes from the changes in the FWC and spectral response of CIS,and the spectral transmittance of lens.

Mutagenic Effect of ^(60)Co γ-rays Irradiation on Turf Characteristics of Buchloe dactyloides (Nutt.) Engelm.

[Objective] This study aimed to investigate the mutagenic effect of 60 Co γ-rays irradiation on turf characteristics of Buchloe dactyloides （Nutt.） Engelm. [Method] Buffalo grass were irradiated with 60 Co γ-rays at five different radiation intensities （1 200, 1 400, 1 600, 1 800, 2 000 Gy） to determine the related turf characteristics and analyze the mutagenic effect of 60 Co γ-rays at different radiation intensities on buffalo grass. [Result] Germination rates of buffalo grass irradiated by different radiation intensities of 60 Co γ-rays varied inconsistently, and the root length and bud length were shorter than the control; compared with the control, the height of irradiated seedlings was significantly reduced, and the number of tillers, plant height, leaf length and leaf blade width were smaller than the control; however, the stolon length, stolon diameter and number of stolon nods had no significant difference compared with the control. [Conclusion] This study laid foundation for determining the appropriate radiation intensity of 60 Co γ-rays and selecting useful mutants of buffalo grass.

Preparation and Characterization of Fe3O4 Magnetic Nano-particles by ^（60）Co γ-ray Irradiation

By using a new method, ^60Co γ-ray irradiation, Fe3O4 magnetic nano-particles were successfully synthesized at room temperature under ambient pressure. The structure, morphology and magnetic properties of these nanoparticles were characterized by X-ray diffraction （XRD）, transmission electron microscope （TEM） and vibrating sample magnetometer （VSM）, respectively. The radiation formation mechanism was also discussed. The results show that the absorbed dose can greatly influence the structure, morphology and magnetic properties of the products. XRD and TEM studies show that the product prepared by γ-ray irradiation （10 kGy） is pure FesO4 phase and the mean diameter of these nano-particles is about 21 nm. The Fe3O4 nano-particles synthesized by γ-ray irradiation （10 kGy） are mainly in small cubic shape and the size uniformity of these particles is good.

Differential Expression of Retrotransposon WIS 2-1A Response to Vacuum, Low-Energy N^+ Implantation and ^(60)Coγ-ray Irradiation in Wheat

Mutagenesis and retrotransposons have a close relationship, but little attention has been paid yet to the activity of retrotransposons produced by physical mutagens. The variation of retrotransposon WIS 2-1A activity in wheat （Triticum aestivum L.） embryos at three different growth times （30 h, 45 h and 60 h） was investigated after they had been treated with N^＋ implantation in a vacuum of 5× 10^-2 Pa and irradiation by ^60Coγ-ray respectively. For each of the three growth times the expression of WIS 2-1A showed almost entirely a same trend of downregulation, upregulation, then downregulation, and upregulation again with the increase in dose of N^＋ implantation, but the expression appeared irregular with the increase in irradiation of ^60Coγ-ray. In conclusion, the acutely activating effect of WIS 2-1A stimulated by vacuum and high dose N^＋ implantation within a shorter incubation time may provide a convenient tool to advance the research on mutagenic breeding and function genes.

The effects of ^(60)Co γ-ray irradiation on the DC characteristics of enhancement-mode AlGaN/GaN high-electron-mobility transistors

The effects of ^60Co γ-ray irradiation on the DC characteristics of AlGaN/GaN enhancement-mode high-electron- mobility transistors （E-mode HEMTs） are investigated. The results show that having been irradiated by^60Co γ-rays at a dose of 3 Mrad （Si）, the E-mode HEMT reduces its saturation drain current and maximal transconductance by 6% and 5%, respectively, and significantly increases both forward and reverse gate currents, while its threshold voltage is affected only slightly. The obvious performance degradation of E-mode A1GaN/GaN HEMTs is consistent with the creation of electronegative surface state charges in the source-gate spacer and gate-drain spacer after being irradiated.

^(60)Co-γ辐射对2种锦带幼苗生长及生理指标的影响

为了探究辐射诱变对“白花锦带花”和“锦带花”形态及生理特性的影响,采用不同剂量(0~300 Gy)的^(60)Co-γ射线辐射“白花锦带花”与“锦带花”休眠期种子,观测辐射对锦带花生长的影响,测定其生长量及幼苗叶片的叶绿素含量、叶绿素荧光指标、光合作用参数、SOD、POD、MDA和可溶性蛋白含量。研究结果显示,由于辐射剂量的增大,苗高、叶长、叶宽、节间距、叶绿素荧光、光合作用参数、SOD活性、POD活性出现了明显的先升高后降低的趋势,在50 Gy时到达了峰值。同时,随着辐射剂量的增加,叶绿素含量和可溶性蛋白含量呈现出下降的趋势,MDA含量明显升高。综上所述,在(2 Gy/min)剂量率的辐射条件下“白花锦带花”种子较适宜的诱变剂量为50 Gy,而“锦带花”以50~100 Gy最合适。

不同^(60)Co-γ辐射剂量对月季仙境、北京红、金凤凰生长和开花的影响

为研究物理辐射对3个月季品种扦插苗的影响,利用0、10、20、40、60、80 Gy剂量的^(60)Co-γ对仙境、北京红、金凤凰月季扦插苗进行辐射处理,测定和分析处理后月季苗的形态指标、突变率、死亡率和半致死率等。结果表明,随着辐射剂量增加,3个月季品种的扦插苗的株高、冠幅、侧枝数、侧枝长度、复叶长、复叶宽随之降低,其中仙境和北京红在10 Gy辐射剂量下生长势最好,而金凤凰在20 Gy生长势最好。供试植株的死亡率随着辐射剂量增加而增加,仙境在10和20 Gy处理下死亡率较低且花色变异较多。仙境、北京红、金凤凰的半致死剂量分别为53、132、19.87 Gy。仙境在10 Gy辐射剂量下突变率最高达31.67%,产生了白色、水粉色、嫩粉色、粉白相间等多种花色突变;金凤凰在10 Gy剂量下花瓣边缘有缺裂,在20 Gy辐射剂量下花瓣边缘深裂、反卷;北京红在10 Gy剂量下有花瓣数量明显增加,花型为千重瓣。综上所述,^(60)Co-γ辐射剂量10和20 Gy有利于促进供试植株的生长,同时产生新的变异花色和新花型。本研究结果为月季的良种选育和新品系培育提供了参考。

Influence of ^(60)Co gamma radiation on fluorine plasma treated enhancement-mode high-electron-mobility transistor

A1GaN/GaN depletion-mode high-electron-mobility transistor （D-HEMT） and fluorine （F） plasma treated enhancement-mode high-electron-mobility transistor （E-HEMT） are exposed to 60Co gamma radiation with a dose of 1.6 Mrad （Si）. No degradation is observed in the performance of D-HEMT. However, the maximum transeonductance of E-HEMT is increased after radiation. The 2DEG density and the mobility are calculated from the results of capacitance-voltage measurement. The electron mobility decreases after fluorine plasma treatment and recovers after radiation. Conductance measurements in a frequency range from 10 kHz to 1 MHz are used to characterize the trapping effects in the devices. A new type of trap is observed in the F plasma treated E-HEMT compared with the D-HEMT, but the density of the trap decreases by radiation. Fitting of Gp/w data yields the trap densities DT = （1-3）Х1012 cm^-2.eV^-1 and DT = （0,2-0.8）Х10^12 cm^2-eV^-1 before and after radiation, respectively. The time constant is 0.5 ms-6 ms. With F plasma treatment, the trap is introduced by etch damage and degrades the electronic mobility. After 60Co gamma radiation, the etch damage decreases and the electron mobility is improved. The gamma radiation can recover the etch damage caused by F plasma treatment.

Apoptotic Sensitivity to Irradiation Increased after Transfection of chk1 Antisense Chain to HL-60 Cell Line

Summary： The HL-60 cells were transfected with chkl antisense and sense chain, and 24 h later subjected to irradiation. Twenty-four h after irradiation, the changes in the chk1 protein expression was assayed by Western blot, and the cell cycles and apoptosis rate detected by FCM. The irradiated apoptosis sensitivity was increased by antisense blocking of chk1 gene in HL-60 cell line with the apoptosis rate being 26.31 %, significantly higher than that by the sense blocking （10.34 %, 0. 025〈P〈0.05）. In HL-60 cells transfected with chkl antisense chain, the G2/M phase arrest was attenua：ted and the cells in G2/M phase were accounted for 38.42 %, significantly lower than those of the cells transfected with chkl sense chain （54.64 %, 0. 005〈P〈0.01）. It was concluded that antisense blocking of chk1 gene could increase the apoptosis sensitivity to irradiation.

^(60)Co-γ辐射诱变在木本植物育种中的研究进展

^(60)Co-γ辐射育种是当前诱变育种研究中应用最广泛的诱变技术,为我国农业的发展作出了巨大的贡献,但是在木本植物育种方面应用相对较少,并且受限于木本植物漫长的生长周期,许多研究难以形成突破性的研究成果,急需系统性、全面性的理论指导。本文对近二十年来木本植物的^(60)Co-γ辐射诱变育种研究进行了总结,详细介绍了辐射诱变原理与方法、辐射材料与辐射强度的选择、突变体鉴定等技术,对^(60)Co-γ辐射诱变效应与分子机理进行了探讨,并提出后续研究的重点方向,为将来木本植物的^(60)Co-γ辐射诱变育种提供理论指导。

^(60)Co-γ辐射对朝天椒种子超微结构、叶表显微结构及分子鉴定的影响

由于朝天椒种质资源多态性低、遗传基础狭窄,加强人工培育朝天椒种质资源尤为重要。为研究^(60)Co-γ辐射对朝天椒的影响,以朝天椒常规品种中农千斤红为试材,对朝天椒干种子进行不同^(60)Co-γ辐射剂量处理(0、25、50、100、200、300、400、500、600 Gy),以无辐射种子为对照,对各处理种子发芽率、成苗率、畸形率、种胚超微结构、叶片显微结构进行测定,并采用SSR分子标记对辐射后长成的幼苗进行分子鉴定。结果表明:辐射剂量小于200 Gy时种子的发芽率、出苗率和成苗率均大于70%;辐射剂量为0、25、50 Gy时辣椒幼苗畸形率均为0%,辐射剂量达100 Gy后畸形率随辐射剂量的增加而增加。对照种子在种胚萌动过程中种胚细胞内线粒体及细胞核等主要细胞器的结构形态均表现正常,^(60)Co-γ辐射剂量为25、200 Gy时种胚内主要细胞器结构和形态仍较为正常,但是随着辐射剂量的增长和辐射时间的增加,种胚细胞的超微结构被损伤的程度愈发严重,线粒体由椭球形膨大成圆球形,脂体变透明,胞质膜、核膜破裂加重,细胞核变形严重,种胚细胞行为异常,直至丧失分裂、代谢功能。经过辐射处理的辣椒种子,长成的幼苗叶片上、下表皮的气孔数与辐射剂量成正相关,表皮细胞的形状也因辐射剂量的增长变得扭曲。经辐射诱变后的长成材料经SSR分子鉴定,较对照发生DNA水平上的变异,扩增谱带突变类型主要为“条带新增型”“混合型”和“条带缺失型”。本试验筛选出了适宜的^(60)Co-γ辐射剂量为200 Gy,以及适宜的引物用于诱变材料SSR分子鉴定,为朝天椒辐射育种提供一定的有益参考。

The Gradient of γ-Rays Irradiation’s Energy and Its Use in Treatment of Cancer Diseases

The Ionising irradiations used mostly in the treatment of tumoral diseasses are: X, γ, β and e irradiations. The discussion will be about γ irradiations, produced in linear accelerator with photon energy 6 MV and 15 MV. It is important to know the absorption performance before and after the electronic equilibrium. This is a reason that we’ve used the function of dose gradient for irradiations γ. It represents the velocity of dose change as a function of depth in tissue. From skin to maximum dose value, the increase of G-function is more accentuated for γ-rays than for β-particles while after that the G-function decreasing is less sharp for γ-rays. Finally, we’ll discuss about the advantages in terms of radiation protection of γ-rays used in radiotherapy.

^(60)Co-γ射线对蝴蝶兰生长发育的影响

为了解^(60)Co-γ射线辐照处理对蝴蝶兰生长的影响及辐射处理后植株的变异表现,对‘郑农火凤凰’和‘郑农鸿运’两个蝴蝶兰品种进行不同剂量的^(60)Co-γ辐射处理,探究辐射处理对蝴蝶兰生长的影响,确定合适的诱变剂量范围。结果表明:(1)^(60)Co-γ辐射处理影响蝴蝶兰植株的生长发育,不同品种的蝴蝶兰对辐射的敏感度不同,‘郑农鸿运’对^(60)Co-γ射线更敏感;(2)植株SPAD值随着辐射剂量的增加呈先增加后降低的趋势,‘郑农火凤凰’和‘郑农鸿运’分别在60Gy和40Gy时具有最高SPAD平均值。(3)辐射处理诱变的植株表观变异具有多样性,不同辐射剂量处理均会导致植株叶片增厚。10Gy剂量的辐射处理时植株出现变异,25Gy时花朵出现变异,40Gy及以上剂量的辐射处理抑制蝴蝶兰植株开花,推测蝴蝶兰合适的诱变剂量范围为10~40Gy。研究结果为蝴蝶兰诱变育种提供了理论依据和剂量参考。

盐酸头孢噻呋注射液^(60)Co-γ辐照灭菌的研究

研究旨在探讨盐酸头孢噻呋注射液使用辐照灭菌的可能性。试验采用不同辐照剂量(8、16、24、32、40 kGy)对盐酸头孢噻呋注射液样品进行辐照,辐照前后样品进行沉降体积比、含量、有关物质及无菌等项目的检测,并将辐照后的样品进行40℃加速稳定性试验。结果显示,与辐照前相比,样品的沉降体积比无明显变化,不同的辐照剂量辐照后均能够保证产品无菌。随着辐照剂量的增加,样品的含量有所降低,杂质有所升高;当辐照剂量为32、40 kGy时,样品性状发生改变。在40℃加速条件下,随着加速时间延长,辐照剂量为8~16 kGy的样品含量略有降低,有关物质略有增加,加速6个月后各检测项均在合格范围内。研究表明,盐酸头孢噻呋注射液样品可采用辐照灭菌,根据产品的加速稳定性结果,初步筛选最佳辐照剂量为8~16 kGy。

^(60)Co辐射灭菌对紫草油质量的影响

目的:考察三批次不同剂量^(60)Co辐射灭菌对院内制剂紫草油的性状、定性鉴别、含量测定、微生物限度检查等质量控制指标的影响,为紫草油实现最终灭菌提供参考。方法:根据2020版《中华人民共和国药典》、四川省药品监督管理局批准的质量标准SZBZ20081112要求,观察紫草油性状变化;采用薄层色谱法对紫草油与紫草对照药材进行定性鉴别;采用紫外分光光度法,检测羟基萘醌总色素含量,在520 nm波长处测定吸光度,按左旋紫草素(C6H16O5)的吸收系数(E1%1 cm)为242计;采用微生物计数法,进行需氧菌总数、霉菌和酵母菌总数、控制菌检查(金黄色葡萄球菌、铜绿假单胞菌)等微生物限度检测。结果:3 kgy、5 kgy、6 kgy辐射灭菌后的制剂均符合质量标准的要求,10 kgy、20 kgy辐射灭菌后的制剂不符合质量标准的要求。结论:^(60)Co辐射灭菌,具有灭菌作用显著、穿透力强、不需升高温度、无化学残留物、可实现带包装最终灭菌、操作简便等特点,能达到灭菌的效果,不影响紫草油质量,有实用价值。

Preparation and characterization of iron-ore-imbedded silicone rubber materials for radiation protection

Iron-ore-imbedded silicone rubber materials were produced for radiation shielding. Samples were tested against a Co-60 gamma source, which is widely used in nuclear technology and medicine. Decreasing the particle size of iron ore resulted in better gamma radiation protection owing to more homogenous distribution. In addition, the materials had flexible properties up to the addition of 60 wt% iron ore content. Further, 0.5 mm Pb E gamma protection was provided by using 2.06-mm-thick SDT-60 as the Co-60 source. Iron ore–silicone rubber composites are candidate materials for lead-free flexible radiation protection systems owing to their relatively inexpensive and easy production.

Feasibility of using recycled CRT funnel glass as partial replacement of high density magnetite sand in radiation shielding concrete

The recycled cathode ray tube(CRT)funnel glass was used as replacement of magnetite sand in the concrete,and its mass replacement rates were 0,20%,40%and 60%,respectively.The flowability,apparent density and mechanical properties of the radiation shielding concrete were investigated,while itsγ-ray radiation shielding parameters such as linear and mass attenuation coefficients(μandμm,respectively),thickness values of half-value layer(hHVL)and tenth-value layer(hTVL)were obtained by theoretical calculation,experiment and Monte.Carlo N-Particle(MCNP)simulation code.The experimental results show that the flowability of the concrete increases significantly,whilst its apparent density,compressive strength and static elastic modulus decrease slightly.The calculated,simulated and experimentalμm,μ,hHVL and hTVL values of all concrete samples are very consistent at the sameγ-ray photon energy,and it is feasible to use MCNP code to simulateγ-ray radiation shielding parameters of materials.The calculated results show that in a wide range ofγ-ray photon energy,theμm value of the concrete with CRT funnel glass replacing magnetite sand is improved effectively,and its radiation shielding performances are the same as those of the control concrete(M.1).By comprehensively comparing the flowability,mechanical properties andγ-ray radiation shielding properties,the concrete samples with 20%.40%funnel glass as fine aggregate have good performances.

^(60)Co-γ辐射对北美红花七叶树的诱变效应

【目的】为探讨^(60)Co-γ射线对北美红花七叶树种子的诱变效应并确定其辐射半致死剂量。【方法】以北美红花七叶树种子为试材,采用不同辐照剂量(0、100、200、300、400 Gy)^(60)Co-γ进行辐射处理,分析辐射对北美红花七叶树种子出苗及幼苗生长的影响。【结果】辐照剂量与种子相对出苗率为极显著负相关,种子辐射半致死剂量为217.76 Gy。辐射后幼苗出现叶型改变、叶面扭曲、叶边缘变异等,300 Gy剂量下叶型和叶边缘变异比例最高。辐射处理的北美红花七叶树生长性状与对照差异不显著。随着^(60)Co-γ射线辐照剂量的增加,抗氧化酶(SOD、POD、CAT)活性,叶绿素及类胡萝卜素含量均呈现先升高后下降的趋势,抗氧化酶活性在300 Gy最高。相关性分析得出,辐照剂量与复叶宽、小叶宽、可溶性蛋白、相对电导率存在显著相关性。【结论】综合种子半致死剂量和生长、生理指标,确定北美红花七叶树种子适宜的辐照剂量为200~300 Gy。可为七叶树属植物辐射育种提供科学参考。

^(60)Co-γ射线辐射对芦笋种子萌发及幼苗生长的影响

以“冠军”和“鲁芦笋七号”2个品种芦笋种子为试材,采用^(60)Co-γ射线对种子进行辐射处理,研究了不同辐射剂量(100、200、300、400、500、600 Gy)对芦笋种子萌发及幼苗生长的影响,探讨不同品种种子萌发及幼苗生长相关指标对不同辐射处理的响应,以期为芦笋辐射诱变育种研究提供参考依据。结果表明:2个品种的萌发指标均呈现先升高后降低的趋势,在剂量为100 Gy时对种子萌发有促进作用,当剂量达到400 Gy时,胚根、胚芽生长受到强烈抑制;种子成苗率与辐射剂量呈负相关。辐射剂量对幼苗生长的诱变效应也与品种有关,“冠军”幼苗生长与辐射剂量增加呈负相关,“鲁芦笋七号”幼苗的生长与辐射剂量增加呈先升高后降低趋势。线性回归分析结果表明,“冠军”和“鲁芦笋七号”对应的半致死剂量分别为389 Gy和362 Gy。