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Detection of the Oscillation Marks on Casting Slabs Using Magnetic Flux Variation and the Nonexcitation Method
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作者 FENG Kaibin LIU Runcong +3 位作者 LI Silong WU Yunfei NA Xianzhao WANG Xiaodong 《材料导报》 北大核心 2026年第1期149-158,共10页
T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection met... T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection methods face challenges owing to surface oxide scales,and conventional high-precision magnetic sensors are ineffective at high temperatures.To overcome these limitations,a small coil sensor was employed to measure the residual magnetism strength in oscillation traces,using metal magnetic memory and electromagnetic induction methods,which can carry out detection without an external excitation source.Using this technology,the proposed scheme successfully detects defects at high tempe-ratures(up to 670℃)without a cooling device.The key findings include the ability to detect both surface and near-surface defects,such as cracks and oscillation marks,with an enhanced signal-to-noise ratio(SNR)of 7.2 dB after signal processing.The method’s practicality was validated in a steel mill environment,where testing on casting slabs effectively detected defects,providing a foundation for improving industrial quality control.The proposed detection scheme offers a significant advancement in nondestructive testing(NDT)for high-temperature applications,contributing to more efficient and accurate monitoring of ferromagnetic material integrity. 展开更多
关键词 oscillation marks REMANENCE metal magnetic memory near surface defects nondestructive testing(NDT)
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罗浮柿EST-SSR分子标记开发和种群遗传多样性评价
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作者 汤瑞瑜 李想 +2 位作者 黄钰琳 冯钰 张永华 《热带亚热带植物学报》 北大核心 2026年第1期63-71,共9页
该研究基于罗浮柿(Diospyros morrisiana)幼苗转录组数据,利用Candi SSR软件开发了1620对具有多态性的EST-SSR分子标记,并基于随机筛选的15对EST-SSR分子标记对8个天然种源地的157株罗浮柿野生植株的遗传多样性进行评价。结果表明,转录... 该研究基于罗浮柿(Diospyros morrisiana)幼苗转录组数据,利用Candi SSR软件开发了1620对具有多态性的EST-SSR分子标记,并基于随机筛选的15对EST-SSR分子标记对8个天然种源地的157株罗浮柿野生植株的遗传多样性进行评价。结果表明,转录组数据集包含100285条Unigene序列,总长为98738602 bp;其中含有34121个SSR位点,发生频率为34.02%,约每2.89 kb含1个SSR位点。从中随机选择的15对具有良好多态性的EST-SSR引物,多态性信息含量(PIC)为0.244~0.877,均值为0.623,其中12个位点具有高度多态性(PIC:0.543~0.788)。基于15对EST-SSR引物的8个罗浮柿野生种群的观测杂合度为0.503~0.650,期望杂合度为0.574~0.610,Shannon多样性指数为1.072~1.245,表现出中等遗传多样性。罗浮柿野生种群的遗传变异绝大部分在种群内(83.29%),种群间存在广泛的基因流,遗传关系较近。该研究为开展罗浮柿的种质资源评价、遗传多样性分析和分子标记辅助育种提供技术支持和科学依据。 展开更多
关键词 罗浮柿 引物开发 est-ssr 遗传结构 遗传多样性
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基于转录组数据的玉米小斑病菌EST-SSR分子标记开发及多态性分析
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作者 徐超 李迪 +5 位作者 杨艳艳 马旭阳 马庆周 郭雅双 施艳 张猛 《福建农林大学学报(自然科学版)》 北大核心 2026年第1期33-44,共12页
【目的】基于玉米小斑病菌(Bipolaris maydis)转录组数据鉴定简单重复序列(SSR)位点,开发可用于该植物病原真菌种内遗传变异分析的全新DNA分子标记。【方法】使用MISA软件对玉米小斑病菌去冗余的unigenes进行SSR标记检索与分析,采用Prim... 【目的】基于玉米小斑病菌(Bipolaris maydis)转录组数据鉴定简单重复序列(SSR)位点,开发可用于该植物病原真菌种内遗传变异分析的全新DNA分子标记。【方法】使用MISA软件对玉米小斑病菌去冗余的unigenes进行SSR标记检索与分析,采用Primer 3.0设计SSR引物,通过本地BLASTN比对以及原始测序数据的mapping筛选具有潜在扩增多态性的SSR引物,并通过非变性聚丙烯酰胺凝胶电泳验证所筛选引物的有效性、多态性和通用性。【结果】在14549条玉米小斑病菌unigenes序列中共检索到5767个SSR位点,发生频率和分布频率分别为23.52%和39.64%,平均分布距离为4.94 kb。其中,单核苷酸重复类型最丰富,占总SSR位点总数的40.70%,二核苷酸(28.18%)和三核苷酸重复类型(26.69%)次之。A/T、AC/GT、C/G和AG/CT是其优势重复基序,共占SSR位点总数的67.05%。SSR基序的重复次数主要在5~14次之间,以10次重复最多(占25.92%),其中,绝大部分为单核苷酸。SSR序列长度的分布范围为10~84 bp,以长度为10 bp的SSR位点数量最多,占SSR位点总数的23.32%,序列长度≥20 bp(高多态性)的SSR共有1309条,占总数的22.70%。进一步通过生物信息学手段和PCR产物电泳检测从100对随机抽选的引物中筛选得到29对扩增性好且多态性较高的SSR引物。【结论】玉米小斑病菌转录组含丰富的SSR位点,具有开发多态性引物的潜力;本次筛选得到的SSR引物可用于后续玉米小斑病菌的种群变异及遗传图谱等研究。 展开更多
关键词 玉米小斑病 玉蜀黍平脐蠕孢 转录组 est-ssr 多态性
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Mark Ⅲ型围护系统绝缘板安装精益物流应用研究
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作者 孙剑 谭颖 +2 位作者 毛海波 孟天家 朱碧雯 《物流科技》 2026年第3期72-77,共6页
文章针对MarkⅢ型围护系统绝缘板安装过程中在物料搬运、配送延迟及库存管理等方面的物流管理问题,提出精益物流理念与原则中的拉动式生产与配送为核心的解决方案。结合看板管理系统与移动平均法需求预测技术,优化了绝缘板从仓储到安装... 文章针对MarkⅢ型围护系统绝缘板安装过程中在物料搬运、配送延迟及库存管理等方面的物流管理问题,提出精益物流理念与原则中的拉动式生产与配送为核心的解决方案。结合看板管理系统与移动平均法需求预测技术,优化了绝缘板从仓储到安装现场的物流流程,降低了物料搬运损耗与库存积压。为物流优化提供了理论支撑与实践参考,具有一定的工程推广价值。 展开更多
关键词 精益物流 markⅢ型围护系统 绝缘板安装 物流优化 拉动式生产
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冲击载荷下的LNG船Mark Ⅲ型围护系统强度分析和结构优化
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作者 史望 张媛 +3 位作者 张兆德 郝立猛 杨哲宇 康传印 《船舶与海洋工程》 2026年第1期35-41,共7页
为探究液化天然气(Liquefied Natural Gas,LNG)船Mark Ⅲ型液舱围护系统的失效模式和冲击响应,基于Abaqus软件建立其局部模型,归纳其在不同失效模式下的应力分布规律和极限载荷。分析该模型在晃荡冲击作用下的动态应力响应,并通过动态... 为探究液化天然气(Liquefied Natural Gas,LNG)船Mark Ⅲ型液舱围护系统的失效模式和冲击响应,基于Abaqus软件建立其局部模型,归纳其在不同失效模式下的应力分布规律和极限载荷。分析该模型在晃荡冲击作用下的动态应力响应,并通过动态放大系数探究冲击速率与应力峰值的关系。基于Isight优化软件对该模型进行参数分析和以提高静强度为目标的优化研究,梳理不同尺寸参数对模型静强度的影响。在此基础上,结合多岛遗传算法得到优化方案,并对其进行动态模拟试验,结果显示优化后模型的应力峰值在固有频率处的下降幅度达4.5%。该研究可供LNG船Mark Ⅲ型围护系统的优化设计参考。 展开更多
关键词 液化天然气(LNG)船 markⅢ型围护系统 安全性评价 结构强度 尺寸优化
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Impact of pre-neoadjuvant radioactive iodine seed marking on pathologic complete response and survival in early-stage breast cancer patients
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作者 Yihao Geng Qi Zhang +6 位作者 Zhao Bi Zhiqiang Shi Qiuchen Zhao Xiaowei Qi Rongrong Zhao Yongsheng Wang Pengfei Qiu 《Cancer Biology & Medicine》 2026年第1期78-85,共8页
Neoadjuvant therapy(NAT)has become the standard treatment for patients with locally advanced breast cancer and stage II-III HER2-positive(HER2+)or triple-negative breast cancer(TNBC)1,2.It is essential to accurately m... Neoadjuvant therapy(NAT)has become the standard treatment for patients with locally advanced breast cancer and stage II-III HER2-positive(HER2+)or triple-negative breast cancer(TNBC)1,2.It is essential to accurately mark the primary breast tumor and positive axillary lymph nodes(ALNs)prior to NAT to ensure precise surgical excision,guide axillary downstaging,and guarantee reliable lesion retrieval for pathologic evaluation3.The false-negative rate of sentinel lymph node biopsy(SLNB)after NAT can be reduced to<10%by applying modalities,such as the identification of≥3 sentinel lymph nodes(SLNs)with dual-mapping techniques or removal of the marked lymph node with target axillary dissection(TAD)according to the ASCO,NCCN,and CBCS guidelines3-5.However,there is a lack of consensus regarding the optimal methods and materials for accurate marking6,7.Conventional techniques include clip placement,guidewire localization,and carbon or ink tattooing,whereas wireless technologies,such as MagseedR,radiofrequency identification tags,SAVI SCOUTR,and radioactive iodine-125(125I)seeds,have also been adopted.Traditional marking techniques have a localization failure rate of approximately 10%.In contrast,the use of 125I seeds(with a radiation dose of 0.1-0.3 mCi)has significantly improved localization accuracy8,9.Nevertheless,owing to radioactive properties,concerns have been raised regarding the potential impact of 125I seed marking on assessing the pathologic complete response(pCR)after NAT10.Moreover,whether the influence of 125I seed marking on pCR could lead to suboptimal adjuvant treatment decisions and potentially compromise long-term oncologic outcomes has not been established.To investigate the potential impact of 125I seed placement on the pCR rate and long-term outcomes in breast cancer patients receiving NAT,we conducted a retrospective cohort study utilizing propensity score matching(PSM). 展开更多
关键词 surgical excisionguide breast tumor lesion retrieval neoadjuvant therapy nat sentinel lymph node biopsy slnb breast cancer pre neoadjuvant radioactive iodine seed marking pathologic evaluation
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Development and Characterizations of EST-SSR Markers in Rubber Tree(Hevea brasiliensis) 被引量:1
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作者 李德军 邓治 +1 位作者 郭会娜 夏志辉 《Agricultural Science & Technology》 CAS 2014年第5期733-737,共5页
To further develop EST-SSR marker in rubber tree, we assembled the sequences downloaded from NCBI and Malaysia EST databases of rubber tree. By analyzing the assembled 3 733 unigenes, we identified 566 potential SSR s... To further develop EST-SSR marker in rubber tree, we assembled the sequences downloaded from NCBI and Malaysia EST databases of rubber tree. By analyzing the assembled 3 733 unigenes, we identified 566 potential SSR sites in this study. That is to say, there was one EST-SSR in every 3.96 kb. The di-nu-cleotide repeat was the most abundant type, fol owed by tri-, hexa-, tetra- and pen-ta-nucleotide repeat. The most common number of repeat units was 5, fol owed by more than 12, 6 and 7. Of 51 SSR motifs identified in this study, di-, tri-, tetra-, penta- and hexa-nucleotide repeats were 6, 26, 5, 3 and 11 types, respectively. The GA/CT di-nucleotide repeat was the most abundant motif, fol owed by TC/AG, AT/TA, CTT/GAA, TTC/AAG and TCT/AGA. In total, 158 new EST-SSRs were developed and amplified with the DNA of RRIM600 as a template. The results showed that the PCR products of 99 EST-SSRs generated clear amplifying bands. The EST-SSR markers developed in this study further enrich the number of molecular marker in rubber tree, and they wil be widely applied in DNA fingerprinting, genetic diversity, marker-assisted selection and genetic mapping, etc. 展开更多
关键词 est-ssr Rubber tree est-ssr Molecular marker
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Marks恐怖强迫量表在中国应用的信度效度研究 被引量:1
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作者 尹平 赵耕源 周迁漳 《中国临床心理学杂志》 CSCD 2003年第2期113-115,共3页
Objective:To evaluate the reliability and validity of the MSCPOR used in China.Methods:45 subjects with OCD,35 subjects with phobias and 35 subjects with anxiety were selected as patient group,and 44 healthy persons w... Objective:To evaluate the reliability and validity of the MSCPOR used in China.Methods:45 subjects with OCD,35 subjects with phobias and 35 subjects with anxiety were selected as patient group,and 44 healthy persons were selected as control group.All subjects were rated according to the Chinese version of the MSCPOR,the Yale-Brown Obsessive Compulsive Scale(Y-BOCS)and the Hamilton Anxiety Scale(HAMA).Two or three weeks after the first rating,16 health persons were re=rated by MSCPOR;12 patients were re-rated with MSCPOR,Y-BOCS and HAMA.15 subjects were rated with MSCPOR and scored by two independent raters at the same time.Results:Test-retest reliability was 0.72~0.99;the homogeneity reliability(Chronbach’s α )in the OCD group were 0.82~0.88 and in phobias group 0.78~0.82;Spearman correlation coefficients were 0.35~0.94 in OCD group and 0.30~0.84 in phobias group;the inter-rater reliability(kappa index) were 0.53~1.For validity,correlation coefficients( γ )among different dimension of MSCPOR in OCD group was 0.36~0.92 and 0.10~0.80 in phobias group.Spearman correlation coefficients between MSCPOR vs Y-BOCS scores and MSCPOR vs HAMA were 0.62 and 0.41~0.44.The results of discriminate analysis showed that diagnosis error for MSCPOR was 40.1%.Conclusion:The reliability and validity of MSCPOR used in China were satisfactory;MSCPOR isn’t a suitable instrument for diagnosis but good for symptom assessment. 展开更多
关键词 marks恐怖强迫量表 中国 信度 效度 强迫症 恐怖症
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Development of Walnut EST-SSR Markers and Primer Design 被引量:3
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作者 冯怡 张智俊 +1 位作者 张舍龙 罗淑萍 《Agricultural Science & Technology》 CAS 2011年第12期1810-1813,共4页
[Objective] This research aimed to develop walnut EST-SSR markers and design corresponding primers.[Method] 5213 EST sequences of walnut(Juglans regia Linn.) public online in NCBI were used for character analysis wi... [Objective] This research aimed to develop walnut EST-SSR markers and design corresponding primers.[Method] 5213 EST sequences of walnut(Juglans regia Linn.) public online in NCBI were used for character analysis with bioinformatics methods,and primers were designed for the selected EST sequences by using Primer 3.0 software.[Result] 207 SSRs were obtained from the EST sequences,including 188 non-redundant sequences,the detection rate was 3.97% with an average distribution distance of 21.12 kb.Totally 92 types of repeat motifs were involved,which were mainly composed of dinucleotide and trinucleotide,accounting for 31.40% and 35.27% of the total number of repeat motifs,respectively.30 pairs of primers were initially selected from the 50 randomly-selected SSR primers by PCR amplification.[Conclusion] This research would lay foundations for the development of EST-SSR molecular markers in walnut and design of the targeted EST-SSR primers by mining and analyzing the SSR sites in walnut EST sequences. 展开更多
关键词 WALNUT est-ssr MICROSATELLITE PRIMERS
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猕猴桃果肉颜色性状基因及其EST-SSR标记发掘
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作者 孙淑霞 涂美艳 +6 位作者 李靖 陈栋 宋海岩 徐子鸿 廖明安 李明章 江国良 《分子植物育种》 北大核心 2025年第5期1469-1480,共12页
果肉颜色是猕猴桃重要的品质性状,不同果肉颜色的猕猴桃在色素成分、糖和维生素C含量等方面存在很大差异。为了探究猕猴桃果肉颜色形成的分子机制,本研究以红肉猕猴桃‘红实2号’和黄肉猕猴桃‘金实1号’为研究对象,采用RNA-seq技术,通... 果肉颜色是猕猴桃重要的品质性状,不同果肉颜色的猕猴桃在色素成分、糖和维生素C含量等方面存在很大差异。为了探究猕猴桃果肉颜色形成的分子机制,本研究以红肉猕猴桃‘红实2号’和黄肉猕猴桃‘金实1号’为研究对象,采用RNA-seq技术,通过分析果实不同时期不同部位的转录组表达差异。结果表明,编码花青素合成的Achn385311(3GGT)基因可能是控制‘红实2号’内果皮呈红色的主效基因,‘金实1号’后期果肉呈深黄色可能与Achn158981(GT7)、Achn150731、Achn068721(PAO)、Achn282201(PAO)和Achn176251(UGT71A16)等基因的表达调控有关。针对差异表达的230个猕猴桃果肉颜色相关基因,利用Primer Premier 5.0设计出727对EST-SSR引物,以7份不同果肉颜色的猕猴桃基因组DNA为模板,随机选择112对引物进行有效性验证,筛选出了具有清晰的扩增产物的引物78对,有效扩增率为69.64%,58对具有多态性,多态性频率为74.36%。本研究结果为猕猴桃果实呈色机理研究及分子标记辅助育种提供了理论基础。 展开更多
关键词 猕猴桃 转录组 花青素 类胡萝卜素 est-ssr
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基于EST-SSR的钟花樱与近缘种的聚类分析及嫁接亲和性研究
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作者 刘夔 李梓函 +4 位作者 张依 郝文洁 姜蕾 叶琦 付涛 《广西植物》 北大核心 2025年第4期761-772,共12页
该研究以16种樱属植物为研究材料,利用EST-SSR分子标记技术对其进行聚类分析,旨在为钟花樱及其近缘种的物种分类、物种资源保护、砧木选择和杂交亲本选择提供分子水平的依据和技术支持。结果表明:(1)遗传多样性分析发现17对EST-SSR引物... 该研究以16种樱属植物为研究材料,利用EST-SSR分子标记技术对其进行聚类分析,旨在为钟花樱及其近缘种的物种分类、物种资源保护、砧木选择和杂交亲本选择提供分子水平的依据和技术支持。结果表明:(1)遗传多样性分析发现17对EST-SSR引物共检测出98个等位基因,每对引物平均为5.76个,有效等位基因数(N_(e))为1.16~7.64,平均值为3.22;观察杂合度(H_(o))为0.04~0.54,平均值为0.28;期望杂合度(H_(e))为0.58~0.92,平均值为0.77;Shannon’s指数(I)为1.38~2.65,平均值为2.14;多态信息含量(PIC)为0.62~0.92,平均值为0.78。(2)聚类分析结果发现除了野生早樱和黑樱桃外,其余14个物种亲缘关系密切,聚为一大类(遗传相似系数C_(GS)为0.6531~0.9184),其中,钟花樱和高盆樱之间的亲缘关系最高(C_(GS)=0.9184),钟花樱和野生早樱之间的亲缘关系最低(C_(GS)=0.7755),因此,建议使用亲缘关系较远的野生早樱和黑樱桃与钟花樱进行杂交实验。(3)在我国南方的生产实践中,已出现以华中樱为砧木,以钟花樱为接穗嫁接的高接苗。因此,从理论上讲,与钟花樱亲缘关系较近的华中樱、山樱、散毛樱和浙闽樱等也可以作为砧木,但还应考虑砧木的抗性、长势、繁殖和寿命等。通过嫁接实验得知,华中樱和山樱作为砧木嫁接钟花樱成活率最高(≥80%),与分子实验基本一致,比较适合作为嫁接钟花樱的砧木。该研究结果为钟花樱的选育、繁殖、保护和利用以及樱属之间的物种分类提供了分子依据。 展开更多
关键词 樱属 钟花樱 遗传多样性 亲缘关系 育种 est-ssr
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BOCOG Promotes Protection of Olympic Marks
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作者 卢爱龙 《中学生英语(高中版)》 2005年第6期26-26,共1页
The BOCOG promoted the protection of Olympic intellectual property rights(知识产权)by giving out leaflets(传单),showing display boards and playing promotional videos to the public at Beijing Lufthansa Friendship Shopp... The BOCOG promoted the protection of Olympic intellectual property rights(知识产权)by giving out leaflets(传单),showing display boards and playing promotional videos to the public at Beijing Lufthansa Friendship Shopping Mall in eastern part of Beijing on the moming of April 26, 2005. The promotional activity was jointly held by the BOCOG legal department and the Chaoyang Branch of Beijing Adminis tration of Industry and Commerce(BAIC). 展开更多
关键词 BOCOG Promotes Protection of Olympic marks
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A vision-based navigation approach with multiple radial shape marks for indoor aircraft locating 被引量:7
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作者 Zhou Haoyin Zhang Tao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第1期76-84,共9页
Since GPS signals are unavailable for indoor navigation, current research mainly focuses on vision-based locating with a single mark. An obvious disadvantage with this approach is that locating will fail when the mark... Since GPS signals are unavailable for indoor navigation, current research mainly focuses on vision-based locating with a single mark. An obvious disadvantage with this approach is that locating will fail when the mark cannot be seen. The use of multiple marks can solve this problem. However, the extra process to design and identify different marks will significantly increase system complexity. In this paper, a novel vision-based locating method is proposed by using marks with feature points arranged in a radial shape. The feature points of the marks consist of inner points and outer points. The positions of the inner points are the same in all marks, while the positions of the outer points are different in different marks. Unlike traditional camera locating methods (the PnP methods), the proposed method can calculate the camera location and the positions of the outer points simultaneously. Then the calculation results of the positions of the outer points are used to identify the mark. This method can make navigation with multiple marks more efficient. Simulations and real world experiments are carried out, and their results show that the proposed method is fast, accurate and robust to noise. 展开更多
关键词 Flexible mark Indoor aircraft Multiple marks Navigation Vision-based locating
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Cultural Differences in the Translation of Trade Marks
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作者 何懿文 《中国校外教育》 2009年第9期24-24,29,共2页
As more and more Chinese products are getting into foreign markets,it is important to translate a Chinese trade mark into English properly. This paper points out what is a trade mark and its importance in the modern w... As more and more Chinese products are getting into foreign markets,it is important to translate a Chinese trade mark into English properly. This paper points out what is a trade mark and its importance in the modern world. It then gives reason why it is necessary to translate the Chinese trade marks properly into English. It also gives the standard of a good trade mark. Furthermore it analyses several kinds of improper translation and the cause of these mistakes. Last it introduces the main rules and three main skills of translation of trade marks. 展开更多
关键词 中国 商标 翻译 英语
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Differences of EST-SSR and genomic-SSR markers in assessing genetic diversity in poplar 被引量:5
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作者 SONG Yue-peng JIANG Xi-bing +5 位作者 ZHANG Man WANG Ze-liang BO Wen-hao AN Xin-min Zhang De-qiang ZHANG Zhi-yi 《Forestry Studies in China》 CAS 2012年第1期1-7,共7页
We analyzed the genetic differences of 16 poplar clones between genomic-SSR and EST-SSR markers. The statistical results show that the average number of alleles detected by genomic-SSR was 4.1, Shannon's index 1.0646... We analyzed the genetic differences of 16 poplar clones between genomic-SSR and EST-SSR markers. The statistical results show that the average number of alleles detected by genomic-SSR was 4.1, Shannon's index 1.0646, observed heterozygos- ity 0.4427 and expected heterozygosity 0.5523, while for the EST-SSR, the average number of alleles was 2.8, Shannon's index 0.6985, observed heterozygosity 0.2330 and expected heterozygosity 0.4684. Cluster analysis indicated that the EST-SSR capacity of genotypic identification was more precise than that of genomic-SSR. These resuks reveal that EST-SSR and genomic-SSR have statistically significant genetic differences in polymorphism detection and genotypic identification. These differences could provide a theoretical basis for the rational use of SSR markers in species diversity and other related research. 展开更多
关键词 POPLAR GENOMIC-SSR est-ssr genetic differences
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Development of Soybean EST-SSR Markers and Their Use to Assess Genetic Diversity in the Subgenus Soja 被引量:6
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作者 LIU Yu-lin LI Ying-hui +4 位作者 ZHOU Guo-an Uzokwe N CHANG Ru-zhen CHEN Shou-yi QIU Li-juan 《Agricultural Sciences in China》 CSCD 2010年第10期1423-1429,共7页
Developing expressed sequence tag-derived SSR (EST-SSR) markers is imperative in genetic research. In this paper, we reported 37 EST-SSR markers which were developed from 286 unigenes obtained from soybean cDNA libr... Developing expressed sequence tag-derived SSR (EST-SSR) markers is imperative in genetic research. In this paper, we reported 37 EST-SSR markers which were developed from 286 unigenes obtained from soybean cDNA library. Among the 286 markers designed for the 4 accessions of Glycine max and 6 of its wild progenitor (G. soja) within the subgenus Soja, 209 markers amplified DNA fragments, taking 73.1% and 37 markers appeared to be polymorphic, which was 12.9% of the total. The 37 loci detected a total of 142 alleles, while the PIC values varied from 0.194 to 0.794. Both the number of alleles per locus and PIC value were significantly related to the SSR motif. Six EST-SSR loci may be fixed for different alleles between G. max and G. soja since they were particularly polymorphic among the 6 G. soja accessions. A neighbor-joining tree placed the G. max accessions together as a group within the G. soja, though the average genetic distance among G. soja accessions was much higher. These new EST-SSRs markers will be useful for genetic diversity analysis, genetic mapping construction and gene discovery in Soja subgenus. 展开更多
关键词 est-ssr DIVERSITY Soja subgenus
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Genetic Diversity Analysis of Faba Bean (Vicia faba L.) Based on EST-SSR Markers 被引量:4
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作者 GONG Ya-ming XU Sheng-chun +4 位作者 MAO Wei-hua LI Ze-yun HU Qi-zan ZHANG Gu-wen DING Ju 《Agricultural Sciences in China》 CAS CSCD 2011年第6期838-844,共7页
Faba bean (Vicia faba L.), one of the most important legumes in the world, evolved different types of cultivars due to its partial cross-pollination. The development of simple sequence repeat (SSR) markers from ex... Faba bean (Vicia faba L.), one of the most important legumes in the world, evolved different types of cultivars due to its partial cross-pollination. The development of simple sequence repeat (SSR) markers from expressed sequence tags (EST) provided a useful tool for investigation of its genetic diversity. The purpose of the present study was to investigate the genetic diversity of faba bean from China and Europe using EST-SSR markers. 5 031 faba bean ESTs from the NCBI database were downloaded and assembled into 1 148 unigenes. A total of 107 microsatellites in 96 unigenes were identified, indicating that merely 8.36% of sequences contained SSRs. The most abundant SSR within faba bean was tri-nucleotide repeat motif, and among all the tri-nucleotide repeats, the motif AAG/CTT was the most abundant type. Based on these results, 11 EST-SSR markers were used to assess the genetic diversity of 29 faba bean cultivars from China and Europe with two to three alleles per locus. The polymorphism information content value ranged from 0.0644 to 0.4278 with an average of 0.2919. Principal coordinate analysis (PCA) and phylogenetic clustering based on these 11 EST-SSR markers distinguished these cultivars into different groups. The results indicated that faba bean in China had a narrow genetic basis, and the additional sources of genetic cultivars/accessions should be introduced to enhance the genetic variability. The results of this study proved that the EST-SSR marker is very effective in evaluation of faba bean germplasm. 展开更多
关键词 est-ssr expressed sequence tag faba bean genetic diversity MICROSATELLITE
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MEASUREMENT OF 2-DIMENSIONAL DISPLACEMENT USING 2-D ZERO-REFERENCE MARKS 被引量:2
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作者 WangYingnan ZhouChenggang HuangWenhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第2期314-316,共3页
Several 2-D displacement sensing methods are reviewed. As to the crossdiffraction grating, there is no absolute zero-reference. In regards to the optical fiber method,the output signal is affected greatly by the quali... Several 2-D displacement sensing methods are reviewed. As to the crossdiffraction grating, there is no absolute zero-reference. In regards to the optical fiber method,the output signal is affected greatly by the quality of the reflecting surface and it is hard to gethigh resolution. Considering the concentric-circle gratings, the displacement can only be gainedwith complicated calculating of the experiment data. Compared with the advantages and limitations ofthe methods above, a novel 2-D zero-reference mark is especially proposed and demonstrated. Thiskind of mark has an absolute zero-reference when used in pair, and the experimental result is simpleto dispose. By superimposing a pair of specially coded 2-D marks, the correct alignment position ofthe two marks can be detected by the maximum output of the sharp intensity peak. And each slope ofthe peak is of good linearity which can be used to achieve high resolution in positioning andalignment in two dimensions. Design and fabrication of such 2-D zero-reference marks are introducedin detail. The experiment results are agreed with the theoretical ones. 展开更多
关键词 Cross diffraction grating Optical displacement sensor Concentric-circlegratings 2-D zero-reference marks Nano-positioning
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环境史的研究及反思——马立博(Robert B.Marks)教授学术访谈录 被引量:3
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作者 张程娟 张权 《史学月刊》 CSSCI 北大核心 2017年第7期117-123,共7页
环境史近年来成为历史研究的热点领域,马立博教授是西方环境史研究的领军人物。马立博的个人研究理路经历了从社会经济史到环境史的转变,他的众多作品中《虎》是一个关键节点。他的研究理路转变和对环境史的反思,对于我们理解环境史有... 环境史近年来成为历史研究的热点领域,马立博教授是西方环境史研究的领军人物。马立博的个人研究理路经历了从社会经济史到环境史的转变,他的众多作品中《虎》是一个关键节点。他的研究理路转变和对环境史的反思,对于我们理解环境史有很大助益。同时,他仍认同"加州学派"的基本观点,反对欧洲中心论,认为赋予中国关键角色的全球史对于现代世界如何形成的叙事至关重要。他指出中国环境史研究存在的问题并给出了宝贵建议,认为中国环境史研究应该增加更多关于生态科学的议题,注意人与环境互动的复杂性网络,包括我们如何看待环境和将非人类生命纳入我们的叙述体系中,进一步将中国环境史研究扩展到全球史的研究。马立博教授期待中国学者能在这一领域做出全球性的贡献。此外,他在访谈中提到的环境史研究学者及代表作尤其值得关注。 展开更多
关键词 环境史 马立博 中国史 全球史
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Assessment of EST-SSR Markers for Evaluating Genetic Diversity in Watermelon Accessions from Zimbabwe 被引量:5
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作者 Claid Mujaju Jasna Sehic Hilde Nybom 《American Journal of Plant Sciences》 2013年第7期1448-1456,共9页
Fifteen expressed sequence tag (EST)-derived simple sequence repeats (EST-SSRs) were used to investigate genetic diversity in 139 plants obtained from seeds of 35 watermelon accessions collected from all the geographi... Fifteen expressed sequence tag (EST)-derived simple sequence repeats (EST-SSRs) were used to investigate genetic diversity in 139 plants obtained from seeds of 35 watermelon accessions collected from all the geographical provinces of Zimbabwe. In addition, 15 plants representing three commercial varieties developed in the United States (USA) were analyzed for comparison. A total of 65 alleles were detected among all the watermelon accessions. For the 13 polymorphic EST-SSR loci, number of alleles per locus varied from 2 to 13, with an average of 5 alleles per locus. Values for the polymorphic information content increased as the number of alleles increased, and varied from 0.15 to 0.77 with an average of 0.54 suggesting sufficient discriminatory power. Both cluster analysis and principal coordinate analysis (PCA) produced two major clusters;one with the 22 cow-melon accessions and the other with the 16 sweet watermelon accessions. Within the sweet watermelon group, two distinct sub-clusters formed, one of which contained only two of the commercial varieties from USA. Partitioning of genetic variation in the Zimbabwean material using analysis of molecular variation (AMOVA) revealed that 64% of the total variation resides between the two major forms, i.e. sweet watermelons and cow-melons, 28% between accessions within forms and 8% within accessions. The EST-SSR markers revealed a somewhat higher diversity in sweet watermelon accessions compared to that of cow-melons. This finding is contrary to previous reports using other markers (genomic SSR loci or RAPD) and/or a plant material that is likely to have experienced more stringent selection procedures compared to the landraces analyzed in our study. 展开更多
关键词 est-ssrS SWEET WATERMELON Cow-Melons WATERMELON Genetic Diversity
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