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Development of gated fiber detectors for laser-induced strong electromagnetic pulse environments

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Nuclear Science and Techniques 2021年第6期32卷 36-44页

作者： Po Hu zhi-guo ma Kai Zhao guo-Qiang Zhang De-Qing Fang Bao-Ren Wei Chang-Bo Fu Yu-Gang ma Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China School of Nuclear Sciences and Technology University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

With the development of laser technologies,nuclear reactions can happen in high-temperature plasma environments induced by lasers and have attracted a lot of attention from different physical ***,studies on nuclear reactions in plasma are still limited by detecting *** is mainly due to the fact that extremely high electromagnetic pulses(EMPs)can also be induced when high-intensity lasers hit targets to induce plasma,and then cause dysfunction of many types of traditional ***,new particle detecting technologies are highly *** this paper,we report a recently developed gated fiber detector which can be used in harsh EMP *** this prototype detector,scintillating photons are coupled by fiber and then transferred to a gated photomultiplier tube which is located far away from the EMP source and shielded *** those measures,the EMPs can be avoided which may result that the device has the capability to identify a single event of nuclear reaction products generated in laser-induced plasma from noise EMP *** new type of detector can be widely used as a time-of-flight(TOF)detector in high-intensity laser nuclear physics experiments for detecting neutrons,photons,and other charged particles.

关键词： Gated fiber detector Radiation detection High-intensity laser Strong electromagnetic pulses

Isolation and chemotaxonomic significance of stenine- and stemoninine-type alkaloids from the roots of Stemona tuberosa

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Chinese Chemical Letters 2014年第9期25卷 1252-1255页

作者： Rong-Rong Zhang Hai-Yan Tian Yi Wu Xiao-Hui Sun Jian-Long Zhang zhi-guo ma Ren-Wang Jiang Institute of Traditional Chinese Medicine and Natural Products College of PharmacyJinan University Zhongshan Torch Polytechnic Shenzhen Engineering Laboratory of Lingnan Herbal Resource Development and Application Shenzhen Institute for Drug Control

One new stenine-type alkaloid, tuberostemonine D （1）, together with five known stenine-type alkaloids （2-6） and two known stemoninine-type alkaloids （7 and 8）, were isolated from the roots of Stemona tuberosa. Their structures were elucidated by extensive spectroscopic methods （IR, UV, MS, 1D and 2D NMR）, and the structure of I was further confirmed by X-ray diffraction analysis. First simultaneous isolation ofstenine- and stemoninine-type alkaloids not only added a new chemical type and increased the chemical diversity of Stemona tuberosa, but also provided chemotaxonomic clues for the close relationship between genera Stemona and Stichoneuron, and favored retaining them in the same family.

关键词： Sternona tuberosa Alkaloid Tuberostemonine-type

Arsenic Trioxide Induces Apoptosis of Glucocorticoid-Resistant Acute Lymphoblastic Leukemia CEM-C1 Cells

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Chinese Journal of Cancer Research 2009年第3期21卷 217-223页

作者： Jiao Ge Xia guo zhi-gui ma Ling Gu Qiang Li Department of Pediatric Hematology and Immunology West China Second Hospital Sichuan University Chengdu 610041 China

Objective： To explore the effects of arsenic trioxide （ATO） on the apoptosis of glucocorticoid （GC）-resistant T-acute lymphoblastic leukemia （ALL） CEM-C1 cells and its possible mechanisms. Methods： Different concentrations of ATO （0.25 μmol/L-5 μmol/L） were used to induce the apoptosis of CEM-C1 cells. The inhibition rate of cell proliferation and apoptosis were detected by MTT test, Annexin V-FITC/PI flow cytometry and optical microscopy, respectively. RT-PCR was applied to semi-quantitatively analyze the mRNA expression of pro-apoptotic proteins （Bad and PDCD4） and anti-apoptotic proteins （XIAP and MCL-1） induced by different concentrations of ATO at different time points. Results： ATO could inhibit proliferation and induce apoptosis of CEM-C1 cells at a concentration and time dependent manner. Low-dose ATO mildly inhibited the proliferation of CEM-C1 cells while higher concentrations （1 μmol/L and 5 μmol/L） had strong anti-tumor effect with the inhibiting rates of 40.07±7.98% and 88.67±2.88%, respectively. Annexin V-FITC/PI flow cytometry showed that the apoptotic rates of CEM-C1 ceils were significantly increased after 48 hours treatment of different concentrations of ATO. RT-PCR demonstrated up-regulated mRNA expression of pro-apoptotic protein Bad and PDCD4 but down-regulated mRNA expression of anti-apoptotic protein XIAP when CEM-C1 cells were treated with different concentrations of ATO at different time points. The MCL-1 mRNA expression was down-regulated only after the treatment of 5 μmol/L ATO. Conclusion： ATO can inhibit cell proliferation and induce cell apoptosis in GC-resistant CEM-C1 cells. The molecular mechanisms might involve the increased mRNA expression of pro-apoptotic protein Bad and PDCD-4, and rapid down-regulation of XIAP mRNA expression.

关键词： Acute lymphoblastic leukemia CEM-C1 cells Apoptosis arsenic trioxide (ATO)

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan YANG Zhaoyang ma Xingming guo Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

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高温米糠粕蒸汽闪爆工艺优化及蛋白性质分析

食品研究与开发 2017年第2期38卷 95-102页

作者：那治国马永强王鑫哈尔滨商业大学食品工程学院黑龙江哈尔滨150076 黑龙江东方学院食品与环境工程学部黑龙江哈尔滨150066

为提高高温米糠粕中蛋白质的溶解性,以高温米糠粕为原料,研究蒸汽闪爆处理高温米糠粕以提高蛋白质溶解性的最优工艺条件。选择蒸汽压力、保压时间、含水率和颗粒度4个因素分别进行单因素试验,根据单因素试验结果设计Box-Behnken试验,以... 详细信息

为提高高温米糠粕中蛋白质的溶解性,以高温米糠粕为原料,研究蒸汽闪爆处理高温米糠粕以提高蛋白质溶解性的最优工艺条件。选择蒸汽压力、保压时间、含水率和颗粒度4个因素分别进行单因素试验,根据单因素试验结果设计Box-Behnken试验,以氮溶解指数为指标值,采用响应面分析法确定蒸汽闪爆处理的最优工艺参数,并采用扫描电镜、差示扫描热量和表面疏水性测定等方法,对高温米糠蛋白蒸汽闪爆后理化性质的变化进行了研究。结果表明:最优工艺参数为蒸汽压力2.3 MPa、保压时间210 s、含水率57%、颗粒度50目,此条件下氮溶解指数为57.23%,比优化前提高了1.65倍。经蒸汽闪爆处理后米糠粕的聚集体分散开来,整体形态不再保持完整性,且米糠分离蛋白的热稳定性和表面疏水性显著下降。蒸汽闪爆处理能显著改善高温米糠蛋白质的溶解性。

关键词：高温米糠粕蒸汽闪爆响应面法理化性质氮溶解指数

科学技术与法学共荣——中国科学技术法学会2006年盛会

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科技与法律 2007年第1期 86-90页

作者：马治国

中国科学技术法学会2006年年会，是一次在学会历史上具有里程碑意义的盛会。这次会议的成功举行，标志着科技法学再创辉煌机遇的到来，预示着科技法制建设崭新局面的开端。科技法学的创始者们独到的智慧，超前的眼光，精心的设计，不懈... 详细信息

中国科学技术法学会2006年年会，是一次在学会历史上具有里程碑意义的盛会。这次会议的成功举行，标志着科技法学再创辉煌机遇的到来，预示着科技法制建设崭新局面的开端。科技法学的创始者们独到的智慧，超前的眼光，精心的设计，不懈的努力，其成果在本次会议上都开始显现出来。现将本次会议综述如下，以期发扬成绩，总结经验，明确目标，加快发展!

关键词：科学技术法学会中国科技法制建设科技法学总结经验发扬

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辛基二茂铁分子结构特性的量子化学计算

固体火箭技术 2016年第5期39卷 672-677页

作者：郭志贤马晓燕王灵侠孙坤高燕陈智群西北工业大学理学院陕西省高分子科学与技术重点实验室西安710072 西安近代化学研究所西安710065

辛基二茂铁按照取代辛烷异构可分为(1-辛基)-二茂铁、(2-辛基)-二茂铁、(3-辛基)-二茂铁和(4-辛基)-二茂铁。由于目前缺乏高纯度的各种辛基二茂铁,所以也缺乏相关物理性能数据。通过量子化学密度泛函B3LYP的方法,对4种辛基二茂铁异构体... 详细信息

辛基二茂铁按照取代辛烷异构可分为(1-辛基)-二茂铁、(2-辛基)-二茂铁、(3-辛基)-二茂铁和(4-辛基)-二茂铁。由于目前缺乏高纯度的各种辛基二茂铁,所以也缺乏相关物理性能数据。通过量子化学密度泛函B3LYP的方法,对4种辛基二茂铁异构体的结构进行理论计算。结果表明,气相辛基二茂铁的稳定构象中,二茂铁基团构象是重叠式,属于D5h点群,Fe可视为含有一定正电荷的离子;偶极矩分析结果表示,分子极性大小顺序为(4-辛基)-二茂铁>(3-辛基)-二茂铁>(2-辛基)-二茂铁>(1-辛基)二茂铁。用GIAO方法模拟出4种辛基二茂铁的核磁共振碳谱、氢谱,分析了辛基二茂铁中碳原子、氢原子的化学环境,为辛基二茂铁同分异构体的研究工作提供参考。

关键词：量子化学密度泛函 B3LYP 固体推进剂辛基二茂铁

Relationships between Weight Status and Bullying Victimization among School-aged Adolescents in Guangdong Province of China

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Biomedical and Environmental Sciences 2010年第2期23卷 108-112页

作者： QIAO-zhi guo, WEN-JUN ma, SHAO-PING NIE, YAN-JUN XU, HAO-FENG XU, AND YU-RUN ZHANG Department of Noncommunicable Disease Control and Prevention, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 510300, Guangdong, China [a] Department of Noncommunicable Disease Control Prevention Guangdong Provincial Center for Disease Control Prevention Guangzhou 510300 Guangdong China

Objective To examine relationships between weight status and different forms of bullying victimization among adolescents aged 11-18 years. Methods The relationships between weight status and bullying victimization （physical, verbal, and relational） were examined utilizing data from the Guangdong Provincial Youth Health Behavior Survey. Data on height, weight, and victimization behaviors were collected by self-reporting from 12 439 subjects, Х^2 test and logistic regression were used to analyze relationships between weight and bullying victimization. Results The incidence of victimization for adolescents aged 11-18 years was 8.6%, with higher rates for boys （12.4%） than for girls （4.7%）. For children with normal, overweight and obese body mass index （BMI）, the incidence rates of victimization were 8,2%, 17.3%, and 11.5%, respectively. Compared to normal weight, overweight was a risk factor for bullying victimization（OR=1.60, 95% CI： 1.18-2.17）, and it also increased children＇s risk of being teased in a hurtful way （OR=2.13, 95% CI： 1.41-3.24） and being made fun of due to physical appearance （OR=3.58, 95% CI： 2.27-5.67）. Obesity only increased the risk for children of being made tim of due to physical appearance （OR=2.45, 95% CI： 1.44-4.15）. Conclusions The victimization for children at school is common in Guangdong province, China. Overweight and obese children are more likely to be victims of bullying behaviors, especially verbal victimization.

关键词： Body mass index Adolescents Victimization

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin ma Yang Qu Jiaxin Ren Yingying Sun Zhen-Ni guo Yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents