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甘蓝S-位点基因SRK、SLG和SP11/SCR密码子偏好性分析 被引量:6
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作者 张以忠 曾文艺 +8 位作者 邓琳琼 张贺翠 刘倩莹 左同鸿 谢琴琴 胡燈科 袁崇墨 廉小平 朱利泉 《作物学报》 CAS CSCD 北大核心 2022年第5期1152-1168,共17页
S位点是芸薹属植物自交不亲和反应的关键位点,控制自交不亲和反应的识别与启动。为明确甘蓝S位点基因SRK和SLG的S域和SP11/SCR编码序列密码子的使用特性,利用Codon W、SPSS软件、Python程序和EMBOSS在线程序分析甘蓝41个SRK、36个SLG和1... S位点是芸薹属植物自交不亲和反应的关键位点,控制自交不亲和反应的识别与启动。为明确甘蓝S位点基因SRK和SLG的S域和SP11/SCR编码序列密码子的使用特性,利用Codon W、SPSS软件、Python程序和EMBOSS在线程序分析甘蓝41个SRK、36个SLG和11个SP11/SCR等位基因的偏好性,同时通过中性绘图、ENC-GC3绘图、PR2绘图及多元统计分析探讨基因密码子偏好性形成原因,并利用不同方法对其进行聚类分析。结果表明,甘蓝SRK、SLG和SP11/SCR基因编码序列富含A/T,密码子偏好以A/T碱基结尾,偏好性较低。自然选择是影响密码子使用模式的主要因素,突变压力为次要因素,还受到二核苷酸丰度的影响。根据RSCU值发现,SRK和SLG基因高表现密码子有4个,SP11/SCR基因有11个。基于RSCU的聚类能够较准确地反应甘蓝SRK、SLG和SP11/SCR等位基因间的关系,并与基于CDS核酸序列的聚类具有一致性和可靠性。根据密码子使用偏好性和聚类关系发现,SRK的S域和SP11/SCR编码序列在密码子偏好性上可能是协同进化的。这为更好理解甘蓝中密码子的分布机制和SRK、SLG和SP11/SCR基因的进化提供新内容。 展开更多
关键词 甘蓝 自交不亲和 S-位点基因 密码子使用偏好 聚类分析
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Expression profiles of Cry1Ab protein and its insecticidal efficacy against the invasive fall armyworm for Chinese domestic GM maize DBN9936 被引量:7
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作者 LIANG Jin-gang ZHANG Dan-dan +13 位作者 LI Dong-yang ZHAO Sheng-yuan WANG Chen-yao XIAO Yu-tao XU Dong YANG yi-zhong LI Guo-ping WANG Li-li GAO Yu YANG Xue-qing yuan Hai-bin LIU Jian ZHANG Xiu-jie WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期792-803,共12页
The fall armyworm(FAW)Spodoptera frugiperda,which originated in the Americas,is advancing across China and threatening the nation’s maize crops.Currently,one widely used tool for its control is genetically modified(G... The fall armyworm(FAW)Spodoptera frugiperda,which originated in the Americas,is advancing across China and threatening the nation’s maize crops.Currently,one widely used tool for its control is genetically modified(GM)Bacillus thuringiensis(Bt)maize.Sufficient content of Bt protein in appropriate plant parts is crucial for enhancing resistance against insect pests.In this study,we conducted a systematic investigation of Cry1 Ab levels in Chinese domestic GM maize DBN9936,which has recently obtained a biosafety certificate,and evaluated its efficacy against FAW.Quantification of expression levels of Cry1 Ab,via ELISA,indicated a spatio-temporal dynamic,with significant variation of mean Cry1 Ab,ranging from 0.76 to 8.48μg g-1 FW with the Cry1 Ab protein level ranked as:V6-V8 leaf>R1 leaf>R4 leaf>R1 silk>VT tassel>R4 kernel.Among the nine locations,the Cry1 Ab levels in DBN9936 of the Xinxiang,Langfang,and Harbin fields were significantly lower than those from Wuhan and Shenyang,and were slightly,but not significantly lower than those from the other four fields.Furthermore,the artificial diet-Cry1 Ab mixture and plant tissue feeding bioassays revealed that DBN9936 has high efficacy against FAW.The insecticidal efficacy of different tissues against FAW larvae reached 34-100%with a descending order of lethality as follows:VT leaf>R4 leaf>R1 husk>R1 silk>VT tassel>R4 kernel.Taken together,our results showed that Bt-Cry1 Ab maize DBN9936 has potential as a promising strategy to manage FAW. 展开更多
关键词 fall armyworm genetically modified maize DBN9936 Cry1Ab expression control efficacy
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妊娠高血压视网膜病变影响因素分析及血管内皮功能检测的临床意义 被引量:7
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作者 陈艺中 罗红 +2 位作者 袁昌亮 王苏 陈岚 《现代生物医学进展》 CAS 2020年第2期319-323,共5页
目的:探讨妊娠高血压视网膜病变的影响因素及血管内皮功能检测的临床意义。方法:前瞻性选取2017年1月~2018年12月期间湖北省妇幼保健院收治的150例妊娠高血压视网膜病变患者作为观察组,根据国际通用的Duker-Elder眼底分期标准分为Ⅰ期... 目的:探讨妊娠高血压视网膜病变的影响因素及血管内皮功能检测的临床意义。方法:前瞻性选取2017年1月~2018年12月期间湖北省妇幼保健院收治的150例妊娠高血压视网膜病变患者作为观察组,根据国际通用的Duker-Elder眼底分期标准分为Ⅰ期组69例,Ⅱ期组57例,Ⅲ期组24例。选取同时期该院收治的妊娠高血压无视网膜病变患者40例为对照组。采用酶联免疫吸附法检测血清胰岛素样生长因子(IGF-1)、内皮素-1(ET-1)水平,采用Pearson相关性分析IGF-1和ET-1水平与病变程度的相关性,采用多因素Logistic回归分析妊娠高血压视网膜病变的影响因素。结果:随着Duker-Elder眼底分期的增加,血清ET-1水平呈不断升高趋势,IGF-1水平呈不断下降趋势(P<0.05)。Pearson相关性分析显示,病变程度与血清IGF-1水平呈负相关,而与ET-1水平呈正相关(P<0.05)。单因素分析结果显示,妊娠高血压视网膜病变的发生与病程、孕周、血压、体质量、蛋白尿、红细胞压积有关(P<0.05),而与年龄无关(P>0.05)。Logistic回归分析结果显示,病程>3W、血压≥160/110 mm Hg、体质量>85kg、蛋白尿为+++、红细胞压积>0.35均是妊娠高血压视网膜病变发生的独立危险因素(P<0.05),而孕周>28W则是其保护因素(P<0.05)。结论:妊娠高血压视网膜病变患者存在IGF-1、ET-1的异常表达,且其表达水平与病变程度息息相关。血压、病程、蛋白尿、体质量、红细胞压积均是妊娠高血压视网膜病变发生的独立危险因素,孕周则是其保护因素。 展开更多
关键词 妊娠 高血压 视网膜病变 影响因素 胰岛素样生长因子 内皮素-1
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An overview of the resources and environment conditions and major geological problems in the Yangtze River economic zone, China 被引量:6
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作者 Yue-hua Jiang Liang-jun Lin +16 位作者 Li-de Chen Hua-yong Ni Wei-ya Ge Hang-xin Cheng Gang-yi Zhai Gui-ling Wang yi-zhong Ban yuan Li Ming-tang Lei Cheng-xuan Tan Jing-wen Su Quan-ping Zhou Tai-li Zhang Yun Li Hong-ying Liu Ke Peng Han-mei Wang 《China Geology》 2018年第3期435-449,共15页
Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land... Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land planning and construction are studied.The results show that the resource conditions of cultivated land,shale gas,geotherm,lithium and so on are superior in the Yangtze River economic zone,and the resources and environment conditions are conducive to develop the modern agriculture,clean energy industry and strategic emerging industries.3×1013 m^2 farmlands without heavy metal pollution are concentrated;there are three national level shale gas exploration and development bases with explored reserves of 5.441×1011 m^3;geothermal availability is 2.4×109 t of standard coal each year,equivalent to 19% of the amount of coal in 2014;Asia's largest energy lithium metal ore deposit is found.In some parts of Yangtze River economic zone,there are some major geological problems such as active faults,karst collapse,ground subsidence,landslide-collapse-debris flow,affecting the river-crossing channels,high-speed railway,urban agglomeration and green ecological corridor planning and construction.Those problems should be concerned,and the relevant suggestions and countermeasures are put forward.Meanwhile,the ideas to further support the development of the Yangtze River economic zone are put forward. 展开更多
关键词 The Yangtze River economic zone Resources and environment CONDITIONS MAJOR geological problems Environmental GEOLOGY HYDROGEOLOGY Disaster GEOLOGY
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Helicobacter pylori plays a key role in gastric adenocarcinoma induced by spasmolytic polypeptide-expressing metaplasia 被引量:2
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作者 Mian-Li Li Xin-Xin Hong +7 位作者 Wei-Jian Zhang yi-zhong Liang Tian-Tian Cai yi-Fei Xu Hua-Feng Pan Jian-yuan Kang Shao-Ju Guo Hai-Wen Li 《World Journal of Clinical Cases》 SCIE 2023年第16期3714-3724,共11页
Heliobacter pylori(H. pylori), a group 1 human gastric carcinogen, is significantly associated with chronic gastritis, gastric mucosal atrophy, and gastric cancer.Approximately 20% of patients infected with H. pylori ... Heliobacter pylori(H. pylori), a group 1 human gastric carcinogen, is significantly associated with chronic gastritis, gastric mucosal atrophy, and gastric cancer.Approximately 20% of patients infected with H. pylori develop precancerous lesions, among which metaplasia is the most critical. Except for intestinal metaplasia(IM), which is characterized by goblet cells appearing in the stomach glands, one type of mucous cell metaplasia, spasmolytic polypeptide-expressing metaplasia(SPEM), has attracted much attention. Epidemiological and clinicopathological studies suggest that SPEM may be more strongly linked to gastric adenocarcinoma than IM. SPEM, characterized by abnormal expression of trefoil factor 2, mucin 6, and Griffonia simplicifolia lectin II in the deep glands of the stomach, is caused by acute injury or inflammation. Although it is generally believed that the loss of parietal cells alone is a sufficient and direct cause of SPEM, further in-depth studies have revealed the critical role of immunosignals.There is controversy regarding whether SPEM cells originate from the transdifferentiation of mature chief cells or professional progenitors. SPEM plays a functional role in the repair of gastric epithelial injury. However, chronic inflammation and immune responses caused by H. pylori infection can induce further progression of SPEM to IM, dysplasia, and adenocarcinoma. SPEM cells upregulate the expression of whey acidic protein 4-disulfide core domain protein 2 and CD44 variant 9, which recruit M2 macrophages to the wound. Studies have revealed that interleukin-33, the most significantly upregulated cytokine in macrophages, promotes SPEM toward more advanced metaplasia. Overall, more effort is needed to reveal the specific mechanism of SPEM malignant progression driven by H.pylori infection. 展开更多
关键词 Gastric cancers Helicobacter pylori Intestinal metaplasia Macrophages Spasmolytic polypeptide-expressing metaplasia
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Hemolysis attributed to high dose vitamin C:Two case reports
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作者 Shi-Wan Wang Xiao-Wei Zhang +6 位作者 Jin-Xiu Qu yi-zhong Rao Shuai Lu Bing Wang Jia He yuan Zhao Ben-Qiang Rao 《World Journal of Clinical Cases》 SCIE 2024年第17期3168-3176,共9页
BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the se... BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the severity of its adverse effects may have been underestimated.The most serious adverse effect is hemolysis,which may result in acute kidney injury or death.Although glucose-6-phosphate dehydrogenase(G6PD)deficiency is considered to be the main cause,the probability and pathological mechanism are not completely understood,leading to a lack of effective and standardized treatment methods.CASE SUMMARY Two patients with colorectal cancer developed hemolytic anemia after using 1 g/kg HVCT.In contrast to previous cases,the lowest hemoglobin level in the two cases was<50 g/L,which was lower than previously reported.This may be because Case 1 had chronic hepatitis B for many years,which caused abnormal liver reserve function,and Case 2 had grade II bone marrow suppression.Both patients improved and were discharged after blood replacement therapy.Our cases had the most severe degree of hemolysis but the best prognosis,suggesting that our treatment may be helpful for rescue of drug-induced hemolysis.This is the first review of the literature on hemolysis caused by HVCT,and we found that all patients with G6PD deficiency developed hemolysis after HVCT.CONCLUSION G6PD deficiency should be considered as a contraindication to HVCT,and it is not recommended for patients with bone marrow suppression,moderate-tosevere anemia,hematopoietic abnormalities,or abnormal liver and kidney function.Early blood purification and steroid therapy may avoid acute kidney injury or death caused by HVCT-related hemolytic anemia. 展开更多
关键词 HEMOLYSIS Vitamin C Adverse effects Acute kidney injury CANCER Case report
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可缓存筒子纱包装整列系统的设计与实现 被引量:6
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作者 庄英豪 陈纪旸 +2 位作者 栾义忠 陈远方 郭政良 《化工自动化及仪表》 CAS 2019年第2期87-90,共4页
根据全自动筒子纱编织袋包装生产线的生产工艺要求,设计了一种新型的筒子纱整列系统,实现了筒子纱的快速整列装袋功能。相较于传统的整列系统,添加了缓存功能,提高了筒子纱包装的效率。利用西门子的TIA Portal软件进行编程,使用顺序功... 根据全自动筒子纱编织袋包装生产线的生产工艺要求,设计了一种新型的筒子纱整列系统,实现了筒子纱的快速整列装袋功能。相较于传统的整列系统,添加了缓存功能,提高了筒子纱包装的效率。利用西门子的TIA Portal软件进行编程,使用顺序功能图对整列系统的控制程序进行分析与开发。设计出的新型整列系统可以满足整条生产线的效率要求,节省了成本,具有良好的应用前景。 展开更多
关键词 自动控制 筒子纱包装 整列系统 缓存
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浅埋隧道单侧扩建施工方案优化 被引量:5
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作者 谭仪忠 刘元雪 +2 位作者 蔡守军 王培勇 陈俞龙 《公路交通科技》 CAS CSCD 北大核心 2019年第4期108-116,共9页
目前国内外常见隧道扩建施工大都采用传统新建隧道的施工方法,但由于传统开挖方法忽略了原隧道衬砌对围岩的长期支撑稳定优势,降低了施工效率。依托重庆渝州隧道扩建施工实例对扩建优化施工方案进行了深入研究,提出了浅埋隧道单侧扩建... 目前国内外常见隧道扩建施工大都采用传统新建隧道的施工方法,但由于传统开挖方法忽略了原隧道衬砌对围岩的长期支撑稳定优势,降低了施工效率。依托重庆渝州隧道扩建施工实例对扩建优化施工方案进行了深入研究,提出了浅埋隧道单侧扩建优化施工方案,即横向采用合理拱轴线开挖,纵向采用跳槽开挖的新方法。通过现场监控量测和ANSYS三维有限元模拟还原施工全过程进行对比分析。采用优化施工方案时,随着开挖掌子面的推进,原隧道衬砌受压应力计算值增大,纵向跳槽开挖时未拆除的原隧道衬砌能够发挥柱的作用,承担因跳槽开挖而产生的围岩压力,可有效提高施工安全稳定性。横向采用合理拱轴线开挖,使得开挖后围岩压力传递更加合理,并显著降低了初期支护结构拉应力和一定程度上增加了初期支护结构压应力。数值计算结果及现场监控量测数据对比显示,浅埋隧道单侧扩建开挖方案优化后拱顶位移比现状开挖方式小约16%~20%,且拱顶基本不出现受拉区,证明优化后的开挖方案在地下工程开挖卸荷时改变了原围岩的应力路径,能够充分调动围岩的自稳能力。故采用优化施工方案不但能够减少拱顶沉降,降低衬砌的拉应力,还能在保证施工安全的同时缩短施工工期,为今后的类似隧道扩建工程提供借鉴。 展开更多
关键词 隧道工程 施工方案 对比分析 跳槽开挖 浅埋隧道 单侧扩建
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Comparison of the mechanisms of microwave roasting and conventional roasting and of their effects on vanadium extraction from stone coal 被引量:4
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作者 yi-zhong yuan yi-min Zhang +1 位作者 Tao Liu Tie-jun Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第5期476-482,共7页
Experiments comparing microwave blank roasting and conventional blank roasting for typical vanadium-bearing stone coal from Hubei Province in central China, in which vanadium is present in muscovite, were conducted to... Experiments comparing microwave blank roasting and conventional blank roasting for typical vanadium-bearing stone coal from Hubei Province in central China, in which vanadium is present in muscovite, were conducted to investigate the effects of roasting tempera- ture, roasting time, H2SO4 concentration, and leaching time on vanadium extraction. The results show that the vanadium leaching efficiency is 84% when the sample is roasted at 800℃ for 30 min by microwave irradiation and the H2SO4 concentration, liquid/solid ratio, leaching temperature, and leaching time are set as 20vo1%, 1.5:1 mL.g-1, 95℃, and 8 h, respectively. However, the vanadium leaching efficiency achieved for the sample subjected to conventional roasting at 900℃ for 60 min is just 71% under the same leaching conditions. Scanning electron microscopy (SEM) analysis shows that the microwave roasted samples contain more cracks and that the particles are more porous compared to the conventionally roasted samples. According to the results of X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) analyses, neither of these roasting methods could completely destroy the mica lattice structure under the experimental conditions; however, both methods deformed the muscovite structure and facilitated the leaching process. Comparing with conventional roasting, microwave roasting causes a greater deformation of the mineral structure at a lower temperature for a shorter roasting time. 展开更多
关键词 vanadium metallurgy extraction stone coal microwave roasting LEACHING vanadium oxides
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基于决策树模型探讨灯盏细辛和血栓通注射剂治疗脑梗死的成本-效果分析
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作者 高卫芳 郭锦辉 +3 位作者 卢乙众 张之亮 袁红昌 贾素洁 《中国药物评价》 2023年第3期277-280,共4页
目的:研究灯盏细辛注射液和注射用血栓通治疗脑梗死的有效性和经济性。方法:随机将我院2022年1月至2022年6月的脑梗死患者344例分为灯盏细辛组和血栓通组,每组172例,通过spss 23.0软件和决策树模型软件Treeage Pro 2022考察两组的有效... 目的:研究灯盏细辛注射液和注射用血栓通治疗脑梗死的有效性和经济性。方法:随机将我院2022年1月至2022年6月的脑梗死患者344例分为灯盏细辛组和血栓通组,每组172例,通过spss 23.0软件和决策树模型软件Treeage Pro 2022考察两组的有效率和药物经济性,并比较两组的成本-效果比值(ICER)。结果:灯盏细辛组和血栓通组总有效率分别为93%、84.9%,灯盏细辛组相比血栓通组的ICER为583.45元。单因素敏感性分析结果显示脑梗死治疗平均费用和灯盏细辛有效率对ICER值影响较大,概率性敏感性分析显示灯盏细辛相对于血栓通具有经济性概率为77%。结论:患者意愿支付阈值设为29650元,灯盏细辛治疗脑梗死具有较优的疗效和经济性。 展开更多
关键词 决策树模型 脑梗死 成本-效果分析
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DmpIRFs and DmpST:DAMPE instrument response functions and science tools for gamma-ray data analysis 被引量:4
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作者 Kai-Kai Duan Wei Jiang +15 位作者 Yun-Feng Liang Zhao-Qiang Shen Zun-Lei Xu yi-zhong Fan Fabio Gargano Simone Garrappa Dong-Ya Guo Shi-Jun Lei Xiang Li Mario Nicola Mazziotta Maria Ferna Munoz Salinas Meng Su Valerio Vagelli Qiang yuan Chuan Yue Stephan Zimmer 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第9期109-118,共10页
Observing GeV gamma-rays is an important goal of the DArk Matter Particle Explorer(DAMPE)for indirect dark matter searching and high energy astrophysics. In this work, we present a set of accurate instrument response ... Observing GeV gamma-rays is an important goal of the DArk Matter Particle Explorer(DAMPE)for indirect dark matter searching and high energy astrophysics. In this work, we present a set of accurate instrument response functions for DAMPE(DmpIRFs) including the effective area, point-spread function and energy dispersion, which are crucial for gamma-ray data analysis based on statistics from simulation data. A dedicated software named DmpST is developed to facilitate the scientific analyses of DAMPE gamma-ray data. Considering the limited number of photons and angular resolution of DAMPE, the maximum likelihood method is adopted in DmpST to better disentangle different source components. The basic mathematics and framework regarding this software are also introduced in this paper. 展开更多
关键词 GAMMA rays:general instrumentation:detectors methods:statistical
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A thermally reversible supramolecular system based on biphenyl polydiacetylene 被引量:4
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作者 Lei Zhang yi-zhong yuan +1 位作者 Xiao-Hui Tian Jin-Yu Sun 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第9期1133-1136,共4页
A new type of diacetylene monomer which includes a biphenylcarboxylic acid group as its head group is synthesized.Polymerization was performed after monomer form spherical vesicle by self-assembly in the water.The pol... A new type of diacetylene monomer which includes a biphenylcarboxylic acid group as its head group is synthesized.Polymerization was performed after monomer form spherical vesicle by self-assembly in the water.The polydiacetylene displayed completely thermochromic color change in the range of 20-95℃ owing to the presence of strong π-π interaction caused by biphenyl group and hydrogen bonding between head group. 展开更多
关键词 Polydiacetylene Head group Self-assembly Reversible
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甚大面积伽马射线空间望远镜计划 被引量:1
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作者 范一中 常进 +34 位作者 郭建华 袁强 胡一鸣 李翔 岳川 黄光顺 刘树彬 封常青 张云龙 魏逸丰 孙志宇 余玉洪 孔洁 赵承心 藏京京 蒋维 潘旭 韦家驹 汪慎 段凯凯 沈兆强 夏子晴 徐遵磊 冯磊 黄晓渊 蔡岳霖 魏俊杰 曾厚敦 贺昊宁 李剑 杨睿智 颜景志 张毅 吴雪峰 韦大明 《天文学报》 CAS CSCD 北大核心 2022年第3期13-30,共18页
高能伽马射线探测是研究极端天体物理的主要途径之一.空间高能伽马射线探测具有覆盖波段宽、时间连续性好、能量分辨率高等突出优势.在成功研发并运行我国首颗天文卫星—"悟空"号(DArk Matter Particle Explorer,DAMPE)的基础... 高能伽马射线探测是研究极端天体物理的主要途径之一.空间高能伽马射线探测具有覆盖波段宽、时间连续性好、能量分辨率高等突出优势.在成功研发并运行我国首颗天文卫星—"悟空"号(DArk Matter Particle Explorer,DAMPE)的基础上,紫金山天文台联合国内的多家单位提议研制甚大面积伽马射线空间望远镜(Very Large Areagamma-ray Space Telescope,VLAST),该望远镜在GeV-TeV能段接受度高达10 m^(2)·sr,并具有强的MeV-GeV波段探测能力,其综合性能预期比费米卫星的大面积伽马望远镜(Fermi-LAT(Large Area Telescope))提升10倍之上.重点介绍了VLAST的主要科学目标,探测器的初步配置及预期性能指标. 展开更多
关键词 仪器:探测器 伽马射线:普通 辐射机制:非热 粒子天体物理
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基于到达时间量测的多传感器协同定位算法研究 被引量:2
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作者 方艺忠 姜浩楠 +2 位作者 陈旸 蔡远利 孟刚 《导弹与航天运载技术》 CSCD 北大核心 2022年第3期60-63,75,共5页
针对基于到达时间量测的多传感器协同目标定位问题,研究不同准则下的解析算法和数值迭代算法,并分析比较了它们各自的优缺点。首先,通过对原始的高斯-牛顿算法进行修正,改善了数值迭代算法在量测噪声强度较大情况下算法的估计效果。随后... 针对基于到达时间量测的多传感器协同目标定位问题,研究不同准则下的解析算法和数值迭代算法,并分析比较了它们各自的优缺点。首先,通过对原始的高斯-牛顿算法进行修正,改善了数值迭代算法在量测噪声强度较大情况下算法的估计效果。随后,利用热图分析了两类算法在不同目标位置时的估计效果差异。最后,在不同噪声强度下对比了多种算法的估计效果,分析了不同算法效果差异存在的原因以及适用条件。研究结果能够对不同场景下如何选择定位算法提供建议。 展开更多
关键词 到达时间量测 多传感器 协同定位
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装备维修保障能力实战化演练评估组织实施分析 被引量:3
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作者 尹旭阳 阮拥军 +2 位作者 贾仪忠 林源和 赵明 《价值工程》 2021年第5期18-20,共3页
着眼部队编制体制改革后维修保障体系结构变化和评估活动面临的新问题,根据实战化演练评估实践经验和组织实施的有关原则,从演练评估的组织准备、组织实施两个阶段重点入手,规范了组织实施流程、梳理组织实施相关要素,可为陆军部队开展... 着眼部队编制体制改革后维修保障体系结构变化和评估活动面临的新问题,根据实战化演练评估实践经验和组织实施的有关原则,从演练评估的组织准备、组织实施两个阶段重点入手,规范了组织实施流程、梳理组织实施相关要素,可为陆军部队开展评估活动提供了参考。 展开更多
关键词 装备维修保障能力 实战化演练 评估 组织实施
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Implications on the origin of cosmic rays in light of 10 TV spectral softenings 被引量:2
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作者 Cliuan Yue Peng-Xiong Ma +25 位作者 Qiang yuan yi-zhong Fan Zhan-Fang Chen Ming-Yang Cui Hao-Ting Dai Tie-Kuang Dong Xiaoyuan Huang Wei Jiang Shi-Jun Lei Xiang Li Cheng-Ming Liu Hao Liu Yang Liu Chuan-Ning Luo Xu Pan Wen-Xi Peng Rui Qiao yi-Feng Wei Li-Bo Wu Zhi-Hui Xu Zun-Lei Xu Guan-Wen yuan Jing-Jing Zang Ya-Peng Zhang Yong-Jie Zhang Yun-Long Zhang 《Frontiers of physics》 SCIE CSCD 2020年第2期101-109,F0004,共10页
Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Prev... Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons(and probably also for Helium nuclei).Very recently,the DArk Matter Particle Explorer(DAMPE)measurement about the proton spectrum clearly reveals such a softening with a high significance.Here we study the implications of these new measurements,as well as the groundbased indirect measurements,on the origin of CRs.We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously.In the framework of multiple components,we discuss two possible scenarios,the multiple source population scenario and the background plus nearby source scenario.Both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies.Considering the anisotropy observations,the nearby source model is favored. 展开更多
关键词 COSMIC RAYS
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A common origin of muon g-2 anomaly,Galaxy Center GeV excess and AMS-02 anti-proton excess in the NMSSM 被引量:2
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作者 Murat Abdughani yi-zhong Fan +3 位作者 Lei Feng Yue-Lin Sming Tsai Lei Wu Qiang yuan 《Science Bulletin》 SCIE EI CSCD 2021年第21期2170-2174,M0003,共6页
The supersymmetric model is one of the most attractive extensions of the Standard Model of particle physics.In light of the most recently reported anomaly of the muon g-2 measurement by the FermiLab E989 experiment,an... The supersymmetric model is one of the most attractive extensions of the Standard Model of particle physics.In light of the most recently reported anomaly of the muon g-2 measurement by the FermiLab E989 experiment,and the excesses of gamma rays at the Galactic center observed by Fermi-LAT space telescope,as well as the antiproton excess observed by the Alpha Magnetic Spectrometer,we propose to account for all these anomalies or excesses in the Next-to-Minimal Supersymmetric Standard Model(NMSSM).Considering various experimental constraints including the Higgs mass,B-physics,collider data,dark matter relic density and direct detections,we find that a~60 GeV bino-like neutralino is able to successfully explain all these observations.Our scenario can be sensitively probed by future direct detection experiments. 展开更多
关键词 Dark matter Supersymmetry Muon g-2 anomaly Galactic center GeV excess Anti-proton excess Global analysis
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甘蓝自交不亲和相关基因BoPUB9的克隆及表达分析
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作者 谢琴琴 左同鸿 +6 位作者 胡燈科 刘倩莹 张以忠 张贺翠 曾文艺 袁崇墨 朱利泉 《作物学报》 CAS CSCD 北大核心 2022年第1期108-120,共13页
自交不亲和性(self-incompatibility,SI)是指植株的雌蕊对自身花粉和异体花粉进行识别从而抑制自身花粉萌发的特性,PUB(Plant U-Box)蛋白在植物抗逆及信号转导过程中起着重要的作用。本研究通过分析甘蓝自花授粉0~60 min的柱头转录组数... 自交不亲和性(self-incompatibility,SI)是指植株的雌蕊对自身花粉和异体花粉进行识别从而抑制自身花粉萌发的特性,PUB(Plant U-Box)蛋白在植物抗逆及信号转导过程中起着重要的作用。本研究通过分析甘蓝自花授粉0~60 min的柱头转录组数据,筛选到1个受自花授粉诱导上调表达的PUB蛋白编码基因BoPUB9。BoPUB9 cDNA序列长度为1368 bp,gDNA序列全长1720 bp,含有1个臂重复结构域和1个U-box结构域。荧光定量PCR结果显示,BoPUB9基因在甘蓝的不同组织中均有表达,在萼片中的表达量最高,花瓣、雄蕊、柱头表达量次之,在花粉花蕾中表达量相对较低,同GUS染色结果保持一致。BoPUB9基因在自花授粉0~30 min内快速上调表达,15 min后为异花授粉后表达量的20多倍,在30 min后达到差异最大,自花授粉后的表达量为异花授粉的40多倍。亚细胞定位结果显示,BoPUB9蛋白在细胞核和细胞质中均有表达,且BoPUB9蛋白在大肠杆菌中被成功诱导表达,相对分子质量为51 kD,与预测结果一致。酵母双杂交与poll-down结果显示,SRK胞内域与PUB9蛋白存在相互作用。推测BoPUB9可能是一种参与甘蓝自交不亲和反应过程的新基因,这为甘蓝自交不亲和的进一步研究和利用提供了新内容。 展开更多
关键词 甘蓝 基因克隆 自交不亲和 表达分析 酵母双杂交
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具有隐藏故障的多状态竞争失效系统检测策略研究 被引量:1
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作者 张延静 马义中 +2 位作者 沈静远 刘丽君 孟晓华 《中国管理科学》 CSSCI CSCD 北大核心 2021年第12期237-248,共12页
复杂工业系统的故障中有40%属于隐藏故障,若隐藏故障得不到及时消除,则可能导致巨大的经济损失。本文针对具有隐藏故障的多状态竞争失效系统,在考虑不完全检测的基础上,对其进行了维修建模。首先,基于制定的视情维修策略,分析了系统的... 复杂工业系统的故障中有40%属于隐藏故障,若隐藏故障得不到及时消除,则可能导致巨大的经济损失。本文针对具有隐藏故障的多状态竞争失效系统,在考虑不完全检测的基础上,对其进行了维修建模。首先,基于制定的视情维修策略,分析了系统的更新情形;然后,基于所推导出的各种系统更新情形的发生概率,建立了以期望成本率为目标函数,以检测间隔时间为决策变量的维修模型。最后,以电容器组为例对所构建维修模型的适用性和有效性进行了验证,研究结果表明,检测质量对检测策略的制定有重要影响,因此研究具有隐藏故障的多状态竞争失效系统的检测策略时,有必要考虑检测误差。本文提出的维修建模方法不仅能在一定程度上丰富多状态竞争失效系统的维修策略理论与方法,还能为工程实际中复杂工业系统的维修工作提供理论基础与决策依据。 展开更多
关键词 隐藏故障 多状态竞争失效系统 不完全检测 视情维修
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Clinical Observation of Infantile Cerebral Palsy Mainly Treated by Scalp Acupuncture 被引量:1
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作者 REN yi-zhong CHEN Rui-hua LIAO Rong-gui XIAO yuan-chun 《Journal of Acupuncture and Tuina Science》 2003年第6期11-12,共2页
Purpose: The clinical effects of scalp acupuncture in treating infantile cerebral palsy were observed.Methods: Forty-five patients were treated by scalp acupuncture, functional exercise, intravenous drip, and parents&... Purpose: The clinical effects of scalp acupuncture in treating infantile cerebral palsy were observed.Methods: Forty-five patients were treated by scalp acupuncture, functional exercise, intravenous drip, and parents' instructive training.Results: Basic recovery occurred in 4 cases, marked effectiveness in 21 cases and effectiveness in 15 cases. The total effective rate was 88.9%. The shorter duration and the longer course were, the better curative effects got.Conclusion: A combined treatment of scalp acupuncture, physiotherapy and intravenous drip can markedly improve clinical symptoms, signs, and intelligence in children with cerebral palsy. Key Words Cerebral Palsy - Acupuncture Medication Combined - Scalp Acupuncture Author: REN Yi-zhong (1965-), male, attending physicianTranslator: XIAO Yuan-chun 展开更多
关键词 Cerebral Palsy Acupuncture Medication Combined Scalp Acupuncture
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