一种新型物理诱变剂--低温空气等离子体的遗传毒性

以酿酒酵母为指示生物,从致死和诱变两方面的剂量效应关系初步探讨低温空气等离子体的遗传毒性,得到150W放电功率下低温空气等离子体具有波动性致死应及较高的诱变效应。150W低温空气等离子体致死作用的这种特殊剂量效应关系使其诱变作用具有对细胞损伤相对较轻的特征。结果反映低温空气等离子作用作一种新型物理诱变剂的有效性和独特性。     

Penicilliumchrysogenum的低温空气等离子体诱变研究

以产黄青霉菌(Penicillium chrysogenum)Pc05为出发菌株,利用物理诱变方法低温空气等离子体技术对其进行诱变处理,结果表明:在处理时间为30 min内时,产黄青霉孢子的存活率随处理时间变化呈现出明显的“马鞍型”曲线;正突变株占所有突变株比例为44.19％,且负突变率很低.经过初筛、复筛获得突变株a...     

信号分子抑制剂对辐射后NFS-60细胞的影响

为了解造血因子受体信号转导在造血细胞辐射损伤时的变化及其与细胞增殖的关系，应用ＭＴＴ法分别观察了蛋白质酷氨酸和丝苏氨酸激酶及其磷酸酶抑制剂对照射及未照射ＮＦＳ－６０细胞增殖的影响。结果显示，一定浓度的磷酸酶抑制剂可促进细胞增殖，而激酶抑制剂则抑制细胞生长，同未照射细胞相比，磷酸酶抑制剂对３Ｇｙ照射细胞具有更强的促增殖作用，而某些激酶抑制剂则可加重细胞的辐射损伤。提示辐射后ＮＦＳ－６０细胞激酶／磷酸     

少突胶质细胞电离辐射损伤机制的研究进展

少突胶质细胞是中枢神经系统（CNS）电离辐射的重要靶细胞。了解少突胶质细胞的辐射损伤机制，对增强CNS对辐射耐受性、防护和治疗CNS的辐射损伤具有重要意义。本文介绍了电离辐射对少突胶质细胞膜的直接损伤、凋亡、氧化应激、诱导一系列基因表达、兴奋毒性损伤、神经营养因子缺乏、胶质细胞产物的作用等细胞机制，以及辐射诱导少突胶质细胞损伤的细胞凋亡信号转导及基因表达等分子机制。     

a粒子照射诱发细胞存活的旁效应及机理研究

以人-中国仓鼠卵巢杂交细胞（AL细胞）为靶，通过在照射源与受照射细胞间插入网格对细胞进行定比照射，以及用受照射细胞培养液培养未受照射细胞两种方式，检测未受照射细胞存活率变化，研究a粒子照射细胞时对未受照射细胞存活的影响。通过观察自由基清除剂二甲基亚砚（DMSO）和细胞间通讯阻断剂Lindane对a粒子照射诱发的细胞存活旁效应的抑制作用探讨其可能的机理。研究结果表明，a粒子照射细胞时的未受照射细胞，以及受a粒子照射细胞的培养液培养的未受照射细胞，其存活率均明显低于预期或正常细胞水平；而DMSO和Lindane均能明显提高细胞存活率。这提示a粒子照射细胞存在旁效应，活性氧和细胞间通讯在a粒子诱发细胞存活旁效应中可能起着重要作用。     

辐射致人胚肺细胞转化与DNA单链断裂

以细胞转化为实验模型，应用细胞生物学和分子生物学的实验手段，研究了辐射所致仍胚肺细胞体我转化以及辐射对细胞ＤＮＡ单链断裂损伤效应的规律。接受０．２５－５Ｇｙ＾３０Ｃｏγ射线作用后第２０代，各剂量组的人胚肺细胞半固体２琼脂培养集落均明显增加，说明人胚肺细胞在射线作用下发生了转化。而且细胞形态转化的出现具有时相性及作用剂理依赖性，采用缺口翻译技术检测细胞ＤＮＡ单链断裂损伤的结果表明，经不同剂量作用后，     

高能电子线辐射损伤对TGF-β1表达及Ⅰ、Ⅲ型胶原含量的影响

探讨了高能电子线辐射伤后Ⅰ、Ⅲ型胶原含量的改变情况及TGF-β1对其的调控作用。采用电子直线加速器照射制作动物的辐射损伤模型，对NIH3T3细胞进行照射，观察胶原总量及Ⅰ、Ⅲ型胶原含量的改变；测定损伤后细胞因子TGF-β1表达的变化情况。结果显示，损伤后胶原总量变化不大，而Ⅰ型胶原含量下降，Ⅲ型胶原含量上升；损伤后TGF-β1表达量增加。结果提示，放射性皮肤损伤引起了胶原代谢的变化，损伤后胶原代谢的调控机制中，TGF-β1可能起重要作用。     

低剂量辐射诱导小鼠胸腺细胞凋亡及细胞周期进程的 …

应用流式细胞术观察７５ｍＧｙ Ｘ射线诱导小鼠胸腺细胞凋亡及细胞周期进程的适应性反应。结果表明，１．５或２．０Ｇｙ全身照射后，小鼠胸腺细胞凋亡小体（ＴＡＢ）百分数明显增加，Ｓ期ＴＡＢ百分数明显减少，而Ｇ０／Ｇ１和Ｇ２＋Ｍ期ＴＡＢ百分数明显增加；当１．５或２．０Ｇｙ（攻击剂量，Ｄ２）照射前６ｈ给予７５ｍＧｙ（诱导剂量，Ｄ１）照射时，明显减轻Ｄ２对胸腺细胞凋亡及细胞周期进程的损伤作用。提示，低剂量辐射可     

低剂量辐射诱导小鼠胸腺细胞凋亡及细胞周期进程的适应性反应

应用流式细胞术观察７５ｍＧｙＸ射线诱导小鼠胸腺细胞凋亡及细胞周期进程的适应性反应。结果表明，１．５或２．０Ｇｙ全身照射后，小鼠胸腺细胞凋亡小体（ＴＡＢ）百分数明显增加，Ｓ期ＴＡＢ百分数明显减少，而Ｇ０／Ｇ１和Ｇ２＋Ｍ期ＴＡＢ百分数明显增加；当１．５或２．０Ｇｙ（攻击剂量，Ｄ２）照射前６ｈ给予７５ｍＧｙ（诱导剂量，Ｄ１）照射时，明显减轻Ｄ２对胸腺细胞凋亡及细胞周期进程的损伤作用。提示，低剂量辐射可诱导胸腺细胞凋亡及细胞周期进程的适应性反应。     

C谱紫外线对体外培养小鼠胚细胞的影响

本实验对紫外线致体外培养的小鼠胚细胞的效应进行了研究。胚细胞取自１１天胎龄绵小鼠前，后肢芽及中脑，并用小脑成纤维母细胞株３Ｔ３进行参照。实验结果表明，在０－３０Ｊ／ｍ＾２的紫外线照射下观察到胚细胞生长和分化抑制作用及胸腺嘧啶聚合物和光产物的形成。紫外线对胚细胞分化的抑制作用比对增殖和抑制作用强，其对ＤＮＡ的损伤作用在胚细胞与参照细胞间相似，这两类细胞对ＤＮＡ损伤的修复动力学相似。     

Effect of Plasma on the Zeta Potential of Cotton Fabrics

In this work, the effect of a low-temperature plasma on the zeta potential of cotton fabric was studied. The silver particle absorption on cotton fabric when modified by a low-temperature plasma was also investigated. The modification consisted of plasma pre functionalization followed by a one-step wet treatment with silver nitrate solution. The process was performed in a low-temperature plasma medium, using a magnetron sputtering device. Oxygen and nitrogen were used as working gases in the system, and the results were compared. After preparing the samples, the zeta potentials of the untreated and plasma-treated cotton under a constant pH value solution were estimated and compared. Also, Fourier transform infrared spec troscopy (FTIR) was used to examine the functional groups of the corresponding samples. The amounts of silver absorption on plasma treated and untreated cotton were examined using the energy dispersive X-ray (EDX) method. The results show that the amount of zeta potential for the nitrogen plasma treated sample is less and the absorption of silver particles by cotton can be increased strongly with nitrogen plasma treatment.     

The Feasibility of Applying AC Driven Low-Temperature Plasma for Multi-Cycle Detonation Initiation

Ignition is a key system in pulse detonation engines(PDE). As advanced ignition methods, nanosecond pulse discharge low-temperature plasma ignition is used in some combustion systems, and continuous alternating current(AC) driven low-temperature plasma using dielectric barrier discharge(DBD) is used for the combustion assistant. However, continuous AC driven plasmas cannot be used for ignition in pulse detonation engines. In this paper, experimental and numerical studies of pneumatic valve PDE using an AC driven low-temperature plasma igniter were described. The pneumatic valve was jointly designed with the low-temperature plasma igniter,and the numerical simulation of the cold-state flow field in the pneumatic valve showed that a complex flow in the discharge area, along with low speed, was beneficial for successful ignition. In the experiments ethylene was used as the fuel and air as oxidizing agent, ignition by an AC driven low-temperature plasma achieved multi-cycle intermittent detonation combustion on a PDE, the working frequency of the PDE reached 15 Hz and the peak pressure of the detonation wave was approximately 2.0 MPa. The experimental verifications of the feasibility in PDE ignition expanded the application field of AC driven low-temperature plasma.     

低能离子辐照的刺激效应模型

注入离子的质量沉积产物对细胞修复等具有刺激作用。在综合考虑低能离子辐照的能量效应和质量沉积效应的基础上,推导出低能离子辐照下生物体的存活率公式及染色体畸变率和细胞突变率公式,对低能离子辐照下多种生物效应（如特殊的“马鞍型”存活率剂量效应等）作出了很好的拟合。     

Numerical and experimental investigation of plasma plume deflection with MHD flow control

This paper presents a composite magneto hydrodynamics(MHD) method to control the lowtemperature micro-ionized plasma flow generated by injecting alkali salt into the combustion gas to realize the thrust vector of an aeroengine.The principle of plasma flow with MHD control is analyzed.The feasibility of plasma jet deflection is investigated using numerical simulation with MHD control by loading the User-Defined Function model.A test rig with plasma flow controlled by MHD is established.An alkali salt compound with a low ionization energy is injected into combustion gas to obtain the low-temperature plasma flow.Finally,plasma plume deflection is obtained in different working conditions.The results demonstrate that plasma plume deflection with MHD control can be realized via numerical simulation.A low-temperature plasma flow can be obtained by injecting an alkali metal salt compound with low ionization energy into a combustion gas at 1800–2500 K.The vector angle of plasma plume deflection increases with the increase of gas temperature and the magnetic field intensity.It is feasible to realize the aim of the thrust vector of aeroengine by using MHD to control plasma flow deflection.     

Erosion research of CX-2002U carbon composites under low-temperature high-flux hydrogen plasma

The net erosion yield of CX-2002 U carbon fiber composites under high-flux low-temperature hydrogen plasma is investigated using a linear plasma device. It is found that the net erosion yield decreases rapidly first, and then tends to saturate with the increase of hydrogen–plasmaflux. When the temperature of the sample eroded by hydrogen plasma is above 300 °C, the hybridization of electrons outside the carbon atom would change. Then the carbon atoms combine with hydrogen atoms to form massive spherical nanoparticles of hydrocarbon compounds and deposit on the surface at the flux condition of 1.77?×?1022 m-2·s-1. Under the irradiation of hydrogen plasma loaded with negative bias, the surface morphology of the matrix carbon is changed dramatically. Moreover, the energy dependence of mass loss does not increase in proportion to the increase of hydrogen–plasma energy, but reaches a peak around 20 V negative bias voltage. Based on the analysis of different samples, it can be concluded that the enhancement of energy could make a contribution to chemical erosion and enlarge the size of pores existing on the surface.     

Polymer Surface Treatment by Atmospheric Pressure Low Temperature Surface Discharge Plasma： Its Characteristics and Comparison with Low Pressure Oxygen Plasma Treatment

The polymer treatment with a low-temperature plasma jet generated on the atmospheric pressure surface discharge （SD） plasma is performed. The change of the surface property over time, in comparison with low pressure oxygen （O2） plasma treatment, is examined. As one compares the treatment by atmospheric pressure plasma to that by the low pressure O2 plasma of PS （polystyrene） the treatment effects were almost in complete agreement. However, when the atmospheric pressure plasma was used for PP（polypropylene）, it produced remarkable hydrophilic effects.     

Design and characteristics investigation of a miniature low-temperature plasma spark discharge device

Atmospheric pressure low-temperature plasma is a promising tool in biomedicine applications including blood coagulation, bacterial inactivation, sterilization, and cancer treatment, due to its high chemical activity and limited thermal damage. It is of great importance to develop portable plasma sources that are safe to human touch and suitable for outdoor and household operation. In this work, a portable and rechargeable low-temperature plasma spark discharge device (130 mm × 80 mm × 35 mm, 300 g) was designed. The discharge frequency and plume length were optimized by the selection of resistance, capacitance, electrode gap, and ground electrode aperture. Results show that the spark plasma plume is generated with a length of 12 mm and a frequency of 10 Hz at a capacitance of 0.33 μF, resistance of 1 MΩ, electrode gap of 2 mm, and ground electrode aperture of 1.5 mm. Biological tests indicate that the plasma produced by this device contains abundant reactive species, which can be applied in plasma biomedicine, including daily sterilization and wound healing.     

Applications of cold atmospheric plasmas (CAPs) in agriculture: a brief review and the novel development of a radio-frequency CAP jet generator for plant mutation

Cold atmospheric plasmas (CAPs) have shown great applicability in agriculture. Many kinds of CAP sources have been studied in agricultural applications to promote plant growth and cure plant diseases. We briefly review the state-of-the-art stimulating effects of atmospheric-pressure dielectric-barrier-discharge (AP-DBD) plasmas, after the direct or indirect treatment of plants for growth promotion and disease control. We then discuss the special demands on the characteristics of the CAP sources for their applications in plant mutation breeding. An atmospheric and room temperature plasma (ARTP) jet generator with a large plasma irradiation area, a high enough concentration of chemically reactive species and a low gas temperature is designed for direct plant mutagenesis. Experimental measurements of the electrical, thermal and optical features of the ARTP generator are conducted. Then, an ARTP-P (ARTP for plant mutagenesis) mutation breeding machine is developed, and a typical case of plant mutation breeding by the ARTP-P mutation machine is presented using Coreopsis tinctoria Nutt. seeds. Physical and agricultural experiments show that the newly-developed ARTP-P mutation breeding machine with a large irradiation area can generate uniform CAP jets with high concentrations of chemically reactive species and mild gas temperatures, and have significant mutagenesis effects on the Coreopsis tinctoria Nutt. seeds. The ARTP-P mutation breeding machine may provide a platform for systematic studies on mutation mechanisms and results for various plant seeds under different operating conditions in future research.