The characteristics of DNA repair synthesis induced by DNA polymerase β in hepatoma cells after γ rays irradiation

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KELEA, Cosmic Rays, Cloud Formation and Electromagnetic Radiation: Electropollution as a Possible Explanation for Climate Change

The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attraction) from its presumed association with cosmic rays. Cosmic ray delivered KELEA is viewed as normally participating in the formation of cloud condensation nuclei (CCN). It may do so by transforming electrostatically inert particles into electrostatic aerosols capable of acting as CCN. The resulting clouds act as a reflective barrier to some of the infrared radiation from the sun and, thereby, reduce the earth’s heat. This article proposes that increasing levels of electromagnetic radiation in the atmosphere is reducing the capacity of cosmic rays to deliver adequate KELEA to maintain climate stability through optimal cloud formation. Specifically, the fluctuating electrical fields accompanying electromagnetic radiation may do so by competitively withdrawing some of the KELEA from the incoming cosmic rays. Previously described studies by Dr. Wilhelm Reich attributed to an energy force termed orgone, are consistent with weather activity being inducible using a device that likely delivers KELEA to the atmosphere. In addition to the foregoing consideration, there are many agricultural and industrial applications of KELEA activated fluids that can reduce carbon emissions. It is important that the scope of climate science be broadened to include a detailed understanding of KELEA and of its many potential practical applications in addressing global warming.

Effect of ^( 60)Co γ Ray Irradiation on Contents of La, Pr, Yb and Mineral Elements in Fruitbodies of Agaricus biazei Murvill

The effects of 60Co γ ray irradiation on the contents of rare earth and mineral elements and their relativities in the fruitbodies of Agaricus biazei Murvill and their relativities were studied. The results show that there are significant difference at the 0.01 level in the contents of rare earth and mineral elements in the fruitbodies among different treatments, and that the variational laws of different elements contents are different with the varieties of the dosages accordingly. Thereinto, the contents of Pr and Mo increase with the increase of the dosage, but they decrease when the dosage are in a certain degree(1.5 KGy). But the Yb content decreases with the increase of the dosage. The variational laws of the contents of K and Cu were similar along with the variety of the dosage, and they all decrease with the increase of the dosage. But the contents of them increase and are higher than that of the three anterior treatments(0, 0.5, 1.0 KGy) when the dosage are 1.5 KGy. It can be seen that the contents of rare earth and mineral elements in the fruitbodies have something to do with the dosages in different degrees, and that rare earth also has something to do with mineral elements in different degrees. Thereinto there lied good linear relationship between the content of Yb and the dosage.

Measurement of Gamma-Rays Induced Luminescence Generated in a Sapphire Based Fiber-Optic Radiation Sensor

In this study, we fabricated a sapphire based fiber-optic radiation sensor. To evaluate the fiber- optic radiation sensor, we measured the spectrum and intensity of the luminescence generated from the fiber-optic radiation sensor according to the thickness of the PMMA block by irradiation of gamma rays emitted from a Co-60 source. And the result was compared with the value calculated from the formula of Lambert-Beer.

^(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.

Analyzing the transient effects of 60Co gamma rays in a CIS by Monte Carlo method

The objective of this work is to analyze the transient effects of ^60Co gamma rays in the CMOS image sensor (CIS) using the Monte Carlo method, based on Geant4. The track, energy spectrum, and angle of produced electrons when gamma rays traversed a silicon or silicon dioxide cube were calculated. A simplified model of a 500 × 500 CIS array was established, and the transient effects of gamma rays in the CIS were simulated. The raw images were captured when the CIS was irradiated by gamma rays. The experimental results were compared with the simulation results. The characteristics of the typical events induced by transient effects were analyzed.

^(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.

γ radiation caused graphene defects and increased carrier density

We report on a micro-Raman investigation of inducing defects in mono-layer, hi-layer and tri-layer graphene by γ ray radiation. It is found that the radiation exposure results in two-dimensional （2D） and G band position evolution with the layer number increasing and D and D~ bands rising, suggesting the presence of defects and related crystal lattice deformation in graphene. Bi-layer graphene is more stable than mono- and tri-layer graphene, indicating that the former is a better candidate in the application of radiation environments. Also, the DC electrical property of the mono-layer graphene device shows that the defects increase the carrier density.

Effect of Gamma Irradiation on Morpho-Agronomic Characteristics of Groundnut (<i>Arachis hypogaea</i>L.)

Induced mutation in plant improvement has been used in several crops to generate new sources of genetic variations. A study was conducted to determine the effect of different doses of gamma irradiation on different morpho-agronomic characteristics. Agronomic traits that were analyzed included: grain yield, number of pods/plant, number of seeds/plant and weight of 100 seeds and numbers of days to 50% flowering. Morphometric characterisation of the descriptive data included plant height, stem diameter, number of leaves/plant, leaflet length, leaflet width and number of ramification/ plant. Groundnut seeds were treated with various doses of gamma rays (100, 200, 400 and 600 Gy). Among the various dose treatments, gamma rays treatment at 100 Gy resulted in a higher increase of grain yield and other morpho-agronomic parameters especially for the JL24 variety. In fact the gamma irradiation at 100 Gy increased significantly grain yield by 14% for JL24, and 4 % for JL12. The number of pods per plant was increased by 2% for JL12 and 37% for JL24. For the number of seeds per plant, there was a significant increase of 8% for JL12, and 62% for JL24 at 100 Gy. A similar trend was observed for the JL24 at 200 Gy dose. Higher doses of gamma rays (400 and 600 Gy) reduced significantly plant growth and grain yield. The usefulness of the mutants identified in a groundnut breeding program is discussed.

Studies of the radiation environment on the Mars surface using the Geant4 toolkit

The radiation environment on the surface of Mars is a potential threat for future manned exploration missions to this planet.In this study,a simple geometrical model was built for simulating the radiation environment on the Mars surface caused by galactic cosmic rays;the model was built and studied using the Geant4 toolkit.The simulation results were compared with the data reported by a radiation assessment detector(RAD).The simulated spectra of neutrons,photons,protons,α particles,and particle groups Z=3-5,Z=6-8,Z=9-13,and Z=14-24 were in a reasonable agreement with the RAD data.However,for deuterons,tritons,and 3He,the simulations yielded much smaller values than for the corresponding RAD data.In addition,the particles’spectra within the 90 zenith angle were also obtained.Based on these spectra,we calculated the radiation dose that would have been received by an average human body on Mars.The distribution of the dose throughout the human body was not uniform.The absorbed and equivalent doses for the brain were the highest among all of the organs,reaching 62.0±1.7 mGy/y and 234.1±8.0 mSv/y,respectively.The average absorbed and equivalent doses for the entire body were approximately 44 mGy/y and 153 mSv/y,respectively.Further analysis revealed that most of the radiation dose was owing to a particles,protons,and heavy ions.We then studied the shielding effect of the Mars soil with respect to the radiation.The body dose decreased significantly with increasing soil depth.At the depth of 1.5 m,the effective dose for the entire body was 17.9±2.4 mSv/y,lower than the dose limit for occupational exposure.At the depth of 3 m,the effective dose to the body was 2.7±1.0 mSv/y,still higher than the accepted dose limit.

Fast 3D EM scattering and radiation solvers based on MLFMA

As the fastest integral equation solver to date, the multilevel fast multipole algorithm （MLFMA） has been applied successfully to solve electromagnetic scattering and radiation from 3D electrically large objects. But for very large-scale problems, the storage and CPU time required in MLFMA are still expensive. Fast 3D electromagnetic scattering and radiation solvers are introduced based on MLFMA. A brief review of MLFMA is first given. Then, four fast methods including higher-order MLFMA （HO-MLFMA）, fast far field approximation combined with adaptive ray propagation MLFMA （FAFFA-ARP-MLFMA）, local MLFMA and parallel MLFMA are introduced. Some typical numerical results demonstrate the efficiency of these fast methods.

Effect of ^(137)Cs Gamma Rays to Panicles on Rice Anther Culture

Panicles of an indica rice line TM7-5 were subjected to radiation with 137^Cs gamma rays at 0 （control）, 5, 10, 15 and 20 Gy respectively, and then its anthers were cultured. There were slight differences among the treatments in peak emerging time of callus initiation, from 38 to 44 days after inoculation （DAI） as well as the frequency of callus initiation （2.3-3.5%）. About two thirds calli were induced before 44 DAI, and calli derived beyond 60 DAI lost the regeneration ability. Green plant regeneration frequency was significantly stimulated from two- to three-fold by irradiation of the 1370S gamma rays compared with the control, and the maximum was 22,81% （15 Gy）. The culture ability based on callus initiation and green plantlet regeneration was 0.19% for the control while it was over 0.45% for all the irradiated treatments, and the maximum was 0,59% for 15 Gy treatment. The advantages of panicle irradiation before anther culture and the potential application in rice anther culture, especially for recalcitrant indica rice, were discussed.

Radionuclide Contents and Physicochemical Water Quality Indicators in Stream, Well and Borehole Water Sources in High Radiation Area of Abeokuta, Southwestern Nigeria

Water samples from streams, hand-dug wells and boreholes in high background radiation areas in Abeokuta, Nigeria have been collected in order to determine the activity concentrations of 40K, 226Ra and 232Th in the samples as well as their physicochemical characteristics. These parameters were evaluated in order to deter-mine the quality of these water sources to the local population, who use these water resources for drinking and domestic activities. Measurements of radioactivity in the water samples were carried out using γ-ray spectroscopy, while standard chemistry methods were used for the physicochemical determinations of these quality parameters. A total of fourteen representative water samples from streams (7), boreholes (4), and hand dug wells (3) were collected for study. The determined activity concentrations of the radionuclides in these samples were used to calculate the effective dose to the population from due to ingestion of and drink-ing the locally available water. The total annual ingestion effective doses were found to vary between 115.00 &#177;1.15μSv and 1362.30 &#177;438.02 μSv. The physicochemical parameters where found to be lower than the prescribed standard safe limits in the water sources except for the nitrate and phosphate levels which were particularly high in the water samples from boreholes and hand-dug wells. The radiation effective ingestion dose due to ingestion of water from dug wells and streams was found to be higher than the dose due to inges-tion of water from borehole sources in the studied areas. The results obtained in this study, have been taken as a baselines for physicochemical parameters and activity concentrations of natural radionuclides in water samples within Odeda and Obafemi-owode parts of Abeokuta, Nigeria.

^(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。