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Chinese Chemical Letters 2024年第9期35卷 135-139页

作者： Wenyu Gao Liming Zhang Chuang Zhao lixiang liu Xingran Yang Jinbo Zhao Faulty of Chemistry and Life Science Changchun University of TechnologyChangchun 130012China

We describe a versatile electrophile addition/SPR sequence of readily available cyclopropyl carbinols that affords multi-substituted carbonylated cyclopropanes with high *** approach tolerates various heteroatom electrophiles,migration of carbon moiety of all possible hybridization states,facile ring reorganization and natural compound *** examples represent an unprecedented version of SPR wherein migration to a non-benzylic bulky tertiary carbo-cation is realized with promising enantiocontrol.

关键词： Cyclopropeneα-carbinols Electrophile addition Semi-Pinacol rearrangement Cyclopropane

DNA Methylation of KLRC1 and KLRC3 in Autoimmune Thyroiditis:Perspective of Different Water Iodine Exposure

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Biomedical and Environmental Sciences 2024年第9期37卷 1044-1055页

作者： Yao Chen Jinjin liu Mengying Qu Bingxuan Ren Huaiyong Wu Li Zhang Zheng Zhou lixiang liu Hongmei Shen Disorders Control Centre for Endemic Disease ControlChinese Centre for Disease Control and PreventionHarbin Medical UniversityHarbin 150081HeilongjiangChina National Health Commission&Education Bureau of Heilongjiang Province Key Laboratory of Etiology and EpidemiologyHarbin Medical UniversityHarbin 150081HeilongjiangChina Heilongjiang Provincial Key Laboratory of Trace Elements and Human Health Harbin Medical UniversityHarbin 150081HeilongjiangChina Division of Health Risk Factor Monitoring and Control Shanghai Municipal Center for Disease Control and PreventionShanghai 200336China Department of Public Health Administration Affiliated Hospital of Jining Medical UniversityJining 272060ShandongChina Heze Municipal Hospital Shandong Provincial Hospital Heze HospitalHeze 274700ShandongChina

Objective This study aimed to identify differentially methylated genes(DMGs) associated with natural killer cells in patients with autoimmune thyroiditis(AIT), focusing on the influence of varying water iodine exposure *** Participants were divided into categories based on median water iodine(MWI)concentrations: iodine-fortified areas(IFA, MWI 300 μg/L). A total of 176 matched AIT cases and controls were recruited and divided into 89, 40, and 47 pairs for IFA, IAA, and IEA, respectively. DMGs were identified using 850K Bead Chip analysis for 10/10 paired samples. Validation of DNA methylation and m RNA expression levels of the DMGs was conducted using Methyl Target^(TM) and QRT-PCR for 176/176paired *** KLRC1, KLRC3, and SH2D1B were identified as significant DMGs. Validation revealed that KLRC1 was hypomethylated and highly expressed, whereas KLRC3 was hypermethylated and highly expressed in individuals with AIT. Furthermore, KLRC1 was hypomethylated and highly expressed in both IFA and *** The DNA methylation status of KLRC1 and KLRC3 may play crucial roles in AIT pathogenesis. Additionally, DNA methylation of KLRC1 seems to be influenced by different iodine concentrations in water.

关键词： Autoimmune thyroiditis DNA methylation KLRC1 KLRC3 SH2D1B Iodine

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面向多联体叶片的机器人喷涂无干涉路径规划

机械工程学报 2024年第1期60卷 210-219页

作者：漆琪刘礼祥杨吉祥丁汉华中科技大学智能制造装备与技术全国重点实验室武汉430074 中国航发沈阳黎明航空发动机有限责任公司沈阳110043

多联体叶片存在曲面复杂、叶片间距小等结构特点。等离子喷涂为铸造多联体叶片的重要工序,可使叶片表面强化与改性,其喷涂质量直接决定叶片的成品率与性能。现有的机器人等离子喷涂的路径生成主要依靠手动示教,而喷涂过程中的喷涂距离... 详细信息

多联体叶片存在曲面复杂、叶片间距小等结构特点。等离子喷涂为铸造多联体叶片的重要工序,可使叶片表面强化与改性,其喷涂质量直接决定叶片的成品率与性能。现有的机器人等离子喷涂的路径生成主要依靠手动示教,而喷涂过程中的喷涂距离与喷涂夹角无法量化导致喷涂质量不均且示教方法繁琐、效率低。基于此,提出一种面向多联体叶片的工业机器人等离子喷涂无干涉路径生成及光顺方法。首先,根据CAD模型,将多联体叶片型面转为非均匀有理B样条(NURBS)曲面,利用NURBS曲面解析特性,生成约束喷涂行距与喷涂叶片边缘距离的初始路径点;然后将喷涂焰流简化为方向包围盒,将干涉曲面转为三角面片,采用基于分离轴检测的方法进行碰撞干涉检测,生成考虑最小喷涂倾角约束的喷涂姿态。采用基于球面样条四元数插值变步长姿态优化方法进行姿态光顺,生成无干涉且路径光顺的喷涂路径。经过仿真与实验验证,提出干涉避免算法能有效避免喷涂过程中的干涉现象。对比未光顺路径,所提出算法机器人运行效率提高52.6%,机器人振动下降,运行更加平稳,其中关节加速度最大下降55.8%,最小下降2.9%,末端瞬时加速度最大下降39.6%,最小下降14.4%。

关键词：多联体叶片机器人喷涂干涉检测路径光顺

H_(2) FPEF和HFA-PEFF评分在我国射血分数保留心力衰竭及射血分数保留心力衰竭合并心房颤动患者中的适用性分析

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中国医学科学院学报 2024年第2期46卷 154-160页

作者：贾晓艳刘离香王东伟马西文刘永铭郑州大学附属郑州中心医院病案管理科郑州450007 兰州大学第一医院老年心血管科甘肃省老年疾病临床医学研究中心兰州730000 郑州大学附属郑州中心医院心脏康复科郑州450007 郑州大学附属郑州中心医院老年医学科郑州450007

目的分析H_(2) FPEF和HFA-PEFF评分对我国单纯射血分数保留的心力衰竭(HFpEF)和HFpEF合并心房颤动(AF)的诊断价值,并探讨其相关因素。方法本研究为横断面研究,连续纳入2009至2020年兰州大学第一医院老年心血管内科收治的HFpEF患者835例... 详细信息

目的分析H_(2) FPEF和HFA-PEFF评分对我国单纯射血分数保留的心力衰竭(HFpEF)和HFpEF合并心房颤动(AF)的诊断价值,并探讨其相关因素。方法本研究为横断面研究,连续纳入2009至2020年兰州大学第一医院老年心血管内科收治的HFpEF患者835例,根据是否合并AF分为HFpEF合并AF组(n=267)和单纯HFpEF组(n=568);采用HFA-PEFF和H_(2) FPEF评分进行回顾性诊断,并评估两种评分系统诊断的一致性。选取同期136名年龄、性别分别与观察组频数匹配的健康人作为健康对照组,分别对HFpEF合并AF和单纯HFpEF进行受试者工作特征曲线分析,评估H_(2) FPEF和HFA-PEFF两种评分识别HFpEF合并AF和单纯HFpEF的能力。结果HFpEF合并AF组和单纯HFpEF组HFA-PEFF评分比较差异无统计学意义(P=0.070),但HFpEF合并AF组平均H_(2) FPEF评分和评分≥6分的比例均明显高于单纯HFpEF组(P均<0.001)。受试者工作特征曲线分析显示,HFA-PEFF和H_(2) FPEF评分诊断全部HFpEF患者的效能均较高,受试者工作特征曲线下面积(AUC)分别为0.892和0.922,最佳临界值均为4。HFA-PEFF评分诊断单纯HFpEF和HFpEF合并AF的效能接近,AUC分别为0.899和0.911。H_(2) FPEF评分诊断HFpEF合并AF的效能较高,AUC约为1.000,而诊断单纯HFpEF的价值相对较低,AUC为0.885。结论HFA-PEFF评分在单纯HFpEF和HFpEF合并AF中均具有较高的适应性,但H_(2) FPEF评分可能低估了我国患者的单纯HFpEF,H_(2) FPEF评分在我国单纯HFpEF患者中的适用性有待进一步研究。

关键词：射血分数保留的心力衰竭心房颤动 H_(2)FPEF评分 HFA-PEFF评分

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混动叉车势能与制动能量联合回收系统设计及AMESim-Simulink仿真分析

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液压与气动 2024年第9期48卷 179-188页

作者：刘理想祝俊张立杰王博江苏大学机械工程学院江苏镇江212013

针对混动叉车频繁升降及起停制动造成能量损耗严重等问题,聚焦混动叉车势能回收与行车时双动力能源分配控制策略能效提升的关键技术,进行了混动叉车势能与制动能量联合回收系统设计。在传统混动叉车并联式混动系统基础上改进优化,运用... 详细信息

针对混动叉车频繁升降及起停制动造成能量损耗严重等问题,聚焦混动叉车势能回收与行车时双动力能源分配控制策略能效提升的关键技术,进行了混动叉车势能与制动能量联合回收系统设计。在传统混动叉车并联式混动系统基础上改进优化,运用前向建模思想搭建仿真模型。为实现精准控制液压缸位移,提出了一种模糊PID自适应控制系统;为优化混动叉车在行车时发动机和驱动电机的工作效率并进行制动能量回收,基于发动机最优工作曲线提出一种制动能量回收控制策略。最后基于JB/T 11988—2014制定多种工况,运用AMESim和Simulink进行多种工况下仿真对比试验,验证该方法有效性,实现能量回收效率提升,势能与制动能量联合回收效率最高可达56.86%。

关键词：混动叉车势能回收制动能量回收模糊控制 PID AMESim-Simulink仿真

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高速公路钢箱梁施工技术研究及应用

葛洲坝集团科技 2024年第3期 32-35页

作者：刘科田少刚刘利祥中国葛洲坝集团三峡建设工程有限公司湖北省宜昌市443000

本文以武汉至重庆高速公路武汉至汉川段二标项目为例,从施工重难点、主要施工技术、施工工艺等方面详细阐述了钢箱梁安装施工技术,该技术不仅保证孝洪高速正常通行,而且提高了施工质量和进度,对类似工程施工具有较好的指导意义。

关键词：钢箱梁临时支架原位吊装交通疏导

Towards an end-to-end delay analysis of LEO satellite networks for seamless ubiquitous access

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Science China(Information Sciences) 2013年第11期56卷 5-17页

作者： CHEN JianZhou liu lixiang HU XiaoHui Science and Technology on Integrated Information System Laboratory Institute of SoftwareChinese Academy of Sciences University of Chinese Academy of Sciences

LEO satellite networks,with moderate propagation delay and low terminal power requirement,are considered as a promising solution to providing global seamless access services for ubiquitous *** order to satisfy the requirement of accessing computing resource for users,end-to-end delays should be bounded for a continual and reliable *** given dynamic topology and non-uniform distribution of terrestrial users,end-to-end delays within LEO satellite networks are liable to ***,to examine the delay constraint,an analytical model based on a tandem queue is established under a hot-spot trafc pattern,which is unfavorable for bounded *** departure interval moments of a target flow are calculated and ftted for the next link as input parameters,from which queuing delays under cross flows are iteratively *** analytical results show that this model is able to depict the influence by the trafc pattern with satisfying accuracy,which is valuable for the design of routing schemes in satellite networks.

关键词： LEO satellite networks delay analysis tandem hot-spot trafc

微丝调控卵母细胞减数分裂成熟的分子机制研究进展

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中国畜牧杂志 2024年第5期60卷 23-33页

作者：张旭林刘理想范冰峰张颖许保增中国农业科学院特产研究所吉林长春130117 中国农业科学院研究生院北京100081

卵母细胞在与精子融合形成合子前会经历2轮减数分裂。与有丝分裂不同的是,2次减数分裂都是不对称的,最终会产生1个大体积的具有全能性单倍体卵母细胞和2个小体积的注定退化的极体。肌动蛋白丝作为卵母细胞中的细胞骨架,与分裂过程中的... 详细信息

卵母细胞在与精子融合形成合子前会经历2轮减数分裂。与有丝分裂不同的是,2次减数分裂都是不对称的,最终会产生1个大体积的具有全能性单倍体卵母细胞和2个小体积的注定退化的极体。肌动蛋白丝作为卵母细胞中的细胞骨架,与分裂过程中的囊泡转运、细胞核定位、纺锤体迁移与锚定、极体排出和染色体分离等生物学事件存在重要联系。本文以哺乳动物为模型,总结了肌动蛋白在卵母细胞减数分裂成熟过程中的重要调节机制与信号通路,以期为进一步研究卵母细胞成熟过程的调控机制提供参考。

关键词：卵母细胞减数分裂肌动蛋白哺乳动物

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广东省污染土壤水泥窑协同处置技术应用研究

广东化工 2024年第7期51卷 127-131页

作者：廖敏劼刘理祥王晨莹广东省固体废物和化学品环境中心广东广州510000

水泥窑协同处置技术可快速将污染土壤从场地移除,缩短修复工期,消除环境风险,其作为“资源化、无害化”的典范得到广泛应用。通过数据分析,2016~2022年,广东省采用水泥窑协同处置技术的修复地块数量经历了“缓慢上升-下降-快速上升-急... 详细信息

水泥窑协同处置技术可快速将污染土壤从场地移除,缩短修复工期,消除环境风险,其作为“资源化、无害化”的典范得到广泛应用。通过数据分析,2016~2022年,广东省采用水泥窑协同处置技术的修复地块数量经历了“缓慢上升-下降-快速上升-急剧下降”的变化历程。广东省共有4个地级市的污染地块修复采用了水泥窑协同处置技术,其中涉及的污染地块数量和污染土壤方量最多的为广州市,其次为惠州市、深圳市和中山市。水泥窑可以安全协同处置25种不同的污染物,重金属及无机物污染土壤方量占比最大,为91.89%。广东省水泥生产企业重金属和无机物污染土壤以及重金属有机物复合污染土壤的掺烧比为2%~10%,有机物污染土壤的掺烧比约为5%。2022年广东省61.9%的地级市有水泥生产企业分布,广东省仍拥有巨大的协同处置污染土壤的水泥窑产能潜力。

关键词：广东省污染地块水泥窑协同处置水泥生产企业环境修复

Occurrence of Neoproterozoic low-grade metagranite in the western Beihuaiyang zone,the Dabie orogen

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Chinese Science Bulletin 2010年第30期55卷 3490-3498页

作者： liu YiCan liu lixiang GU XiaoFeng LI ShuGuang SONG Biao Key Laboratory of Crust-Mantle Materials and Environments Chinese Academy of Sciences School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Beifing SHRIMP Center Chinese Academy of Geological Sciences Beijing 100037 China

Based on detailed field investigations and petrographic observations,we discovered Neoproterozoic-emplaced granite from the metavolcanics of the Dingyuan Formation in the western Beihuaiyang zone,the Dabie orogen. This study reports the results of zircon U-Pb dating and preliminary petrographic observations on two metagranite samples. The studied rocks experienced epidote-amphibolite facies metamorphism and strong structural deformation. Their U-Pb ages are 726 ± 6 and 758 ± 12 Ma,respectively,similar to those for the Luzhenguan complex in the eastern segment of the Beihuaiyang zone. In combination with previously determined 635 ± 5 Ma low-grade metagabbro,this study suggests the occurrence of at least two types of Neoproterozoic intrusive rocks in the Beihuaiyang zone,the northern margin of the South China Block (SCB):726-758 Ma metagranite and 635 Ma metagabbro. These rocks occur within the metamorphosed Ordovician volcanic zone (originally named the Dingyuan Formation) and are in tectonic contact to each other,but they formed in different tectonic settings. The protolith ages for the Neoproterozoic low-grade metaigneous rocks are in good agreement not only with ages for two episodes of mid-and late-Neoproterozoic mafic and felsic magmatism in the Suizhou and Zaoyang area,Hubei Province,but also agree with protolith ages of ultrahigh-pressure metaigneous rocks in the Dabie-Sulu orogenic belt. In view of their tectonic relationships to country rocks,it appears that these Neoproterozoic low-grade rocks are exotic and they may have been detached and scraped from subducting SCB crust in the early Triassic during the initial continental subduction,and thrusted over Paleozoic metamorphosed rocks in the southern margin of the North China Block during continental collision.

关键词：大别山造山带新元古代北淮阳带低档西部变质作用构造背景苏鲁造山带