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Chiral Lewis Base/Achiral Acid Co-Catalyzed Atroposelective Sulfenylation of Pyrrole Derivatives: Construction of C-N Axially Chiral Sulfides

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Chinese Journal of Chemistry 2024年第17期42卷 2005-2009页

作者： qin yang Hui-Yun Luo Deng Zhu Xin-Yu Zhang Hua Ke Zhi-Min Chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China Engineering Technooy Rearch Centeror Enviromental Proction Materas Pingxng Universty PingangJiangx355China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China

Chiral BINAM-derived selenide/achiral acid co-catalyzed atroposelective electrophilic sulfenylation of pyrrole derivatives has been realized for the first time.A variety of C-N axially chiral sulfur-containing pyrrole derivatives were readily obtained in moderate to good yields with moderate to excellent *** catalytic system involves sequential desymmetrization and kinetic resolution.

关键词： Electrophilic substitution Desymmetrization Kinetic resolution Atropisomerism Asymmetric catalysis Heterocycles

Mendelian randomization analysis of causal relationship between cheese intake and diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1905-1910页

作者： Cheng-Ye Tang Dong-Yong Tang Ying-qin yang Yu-Bing Liang Hao Liang Department of Ophthalmology the First Affiliated Hospital of Guangxi Medical UniversityNanning 530000Guangxi Zhuang Autonomous RegionChina Department of Ophthalmology the Affiliated Hospital of Guilin Medical UniversityGuilin 541001Guangxi Zhuang Autonomous RegionChina Department of Anesthesiology Guangxi Medical University Cancer HospitalNanning 530000Guangxi Zhuang Autonomous RegionChina

AIM:To assess whether there is a possible causal link between the intake of cheese and the risk of diabetic retinopathy(DR)utilizing a two-sample Mendelian randomization(MR)***:The research data were obtained from summary statistics of genome-wide association studies(GWAS).Genetic loci closely related to cheese intake were extracted as instrumental variables(IVs),and DR was the outcome *** data were extracted from individuals of European *** data of cheese intake consisted of 451486 samples with 9851867 single nucleotide polymorphisms(SNPs),while the DR data consisted of 206234 samples with 16380446 ***-one genetic loci closely related to cheese intake were selected as *** analysis was performed by inverse-variance weighted(IVW)method and MR-Egger regression *** causal relationship between cheese intake and DR was evaluated using odds ratios(ORs)and 95%confidence intervals(CIs).Egger-intercept test was used to test horizontal pleiotropy and sensitivity analysis was performed by leave-one-out ***:The P value of the IVW method was less than 0.05,indicating a significant negative correlation between cheese intake and ***-Egger regression showed that the intercept was 0.01 with a standard error of 0.022,and a P-value of 0.634,indicating no evidence of horizontal pleiotropy affecting the IVs related to the exposure ***,heterogeneity tests confirmed the absence of heterogeneity,and the“leave-one-out”sensitivity analysis demonstrated that the results were ***:Cheese intake is causally negatively correlated with the occurrence of DR,and cheese intake could reduce the risk of DR.

关键词： cheese intake diabetic retinopathy Mendelian randomization analysis

Regulable toehold lock for the effective control of strand displacement reaction sequence and circuit leakage

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Chinese Chemical Letters 2024年第7期35卷 372-376页

作者： Kuangdi Luo yang qin Xuehao Zhang Hanxu Ji Heao Zhang Jiangtian Li Xianjin Xiao Xinyu Wang Department of Breast Surgery Second Hospital of Jilin UniversityChangchun 130041China Institute of Reproductive Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Laboratory Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Pancreatic Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China School of Life Science and Technology Wuhan Polytechnic UniversityWuhan 430023China

Strand displacement reaction enables the construction of enzyme-free DNA reaction networks,thus has been widely applied to DNA circuit and *** has the characteristics of high efficiency,universality and ***,the existing regulation tools cannot enable effective control of the reaction sequence,which undoubtedly limits the construction of complex nucleic acid ***,we developed a regulation tool,toehold lock,and achieved strict control of reaction sequence without loss of the main reaction signal ***,we applied the tool to scenarios such as seesaw circuits,AND/OR logic gates,and entropy-driven circuits,and respectively demonstrated its significant superiority compared to the original *** believe that the proposed toehold lock has greatly optimized the efficiency of DNA strand displacement-based networks,and we anticipate that the tool will be widely used in multiple fields.

关键词： DNA circuit Toehold lock DNA strand displacement Reaction sequence Seesaw circuit

Challenges and Prospects of Molecular Spintronics

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Precision Chemistry 2024年第1期2卷 1-13页

作者： Xianrong Gu Lidan Guo yang qin Tingting yang Ke Meng Shunhua Hu Xiangnan Sun Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190P.R.China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049P.R.China

Molecular spintronics,as an emerging field that makes full use of the advantage of ultralong room-temperature spin lifetime and abundant electrical-optical-magnetic properties of molecular semiconductors,has gained wide attention for its great potential for further commercial *** the significant progress that has been made,there remain several huge challenges that limit the future development of this *** Perspective provides discussions on the spin transport mechanisms and performances of molecular semiconductors,spinterface effect,and related spin injection in spintronic devices,and current spin-charge interactive functionalities,along with the summarization of the main obstacles of these ***,we particularly propose targeted solutions,aiming to enhance the spin injection and transport efficiency by molecular design and interface engineering and explore diverse spinrelated *** this Perspective,we hope it will help the spintronic community identify the research trends and accelerate the development of molecular spintronics.

关键词： Molecular spintronics spin transport spintronic materials spin injection spinterface effect spin-related functionality

Sperm acrosin activity may be a useful factor in choosing between ICSI and IVF for infertile male patients

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Asian Journal of Andrology 2024年第1期26卷 85-90页

作者： Ye-Na Hu Liang Hu Xin-Yu Yin Huan Zhang yang-qin Peng Gang Liu Ge Lin Wei-Na Li The Institute of Reproductive and Stem Cell Engineering School of Basic Medical ScienceCentral South UniversityChangsha 410008China Department of Andrology Reproductive and Genetic Hospital of CITiC-XiangyaChangsha 410013China Clinical Research Center for Reproduction and Genetics in Hunan Province Changsha 410013China Hunan Guangxiu Hi-tech Life Technology Co. Ltd.Changsha 410013China

The clinical applications of acrosin activity are *** analyzed 61578 male partners in infertile couples who visited the outpatient department of the Reproductive and Genetic Hospital of CITIC-Xiangya(Changsha,China)between August 2014 and December 2019 to determine the reference ranges and thresholds for acrosin activity in infertile Chinese men;to determine whether correlations exist between acrosin activity and age,sperm concentration,sperm morphology,or sperm motility;and to evaluate whether acrosin activity could serve as an effective prognostic indicator for choosing between in vitro fertilization(IvF)and intracytoplasmic sperm injection(icsl)in the *** cut-off value for the normal reference range of acrosin activity for male partners in infertile couples was 24.78μlU per 106 *** was no significant association between acrosin activity and age,sperm concentration,semen volume,total sperm count,progressive motility,or total motile spermatozoa.A weak positive correlation was found between acrosin activity and normal sperm *** was a statistically significant difference in abnormal acrosome morphology between the group with high acrosin activity(>24.78μlU per 106 sperm)and the group with low acrosin activity(<24.78μlU per 106 sperm).The group with a low IVF fertilization rate had a high index of abnormal acrosomal morphology at 21.2%,while the group with a high IVF fertilization rate had a low index of 0.2%.At an acrosin activity of<24.78μlU per 10 sperm,in one cycle of the same patient,the fertilization rate,normal fertilization rate,and good-quality embryo rate for Icsl were significantly higher than those for ***,the most promising application of acrosin activity could be in the selection of IcsI over IVF for infertile male patients with complete fertilization failure or a low fertilization rate.

关键词： acrosin activity fertilization rate ICSI IVF semen parameters

Toeless and reversible DNA strand displacement based on Hoogsteen-bond triplex

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Chinese Chemical Letters 2024年第5期35卷 330-337页

作者： yang qin Jiangtian Li Xuehao Zhang Kaixuan Wan Heao Zhang Feiyang Huang Limei Wang Hongxun Wang Longjie Li Xianjin Xiao Institute of Reproductive Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Pancreatic Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Wuhan Polytechnic University Wuhan 430023China

Strand displacement reaction is a crucial component in the assembly of diverse DNA-based nanodevices,with the toehold-mediated strand displacement reaction representing the prevailing ***,the single-stranded Watson-Crick sticky region that serves as the trigger for strand displacement can also cause leakage reactions by introducing crosstalk in complex DNA ***,we proposed the toeless and reversible DNA strand displacement reaction based on the Hoogsteen-bond triplex,which is compatible with most of the existing DNA *** demonstrated that our proposed reaction can occur at pH 5 and can be reversed at pH *** also observed an approximately linear relationship between the degree of reaction and pH within the range of pH 5-6,providing the potential for precise regulation of the ***,by altering the sequence orientation,we have demonstrated that our proposed reaction can be initiated or regulated through the same toeless mechanism without the requirement for protonation in low pH *** on the proposed reaction principle,we further constructed a variety of DNA nanodevices,including two types of DNA logic gates that rely on pH 5/pH 9 changes for initiating and reversing:the AND gate and the OR *** also successfully constructed a DNA Walker based on our proposed reaction modes,which can move along a given track after the introduction of a programmable DNA sequence and complete a cycle after 4 *** findings suggest that this innovative approach will have broad utility in the development of DNA circuits,molecular sensors,and other complex biological systems.

关键词： DNA strand displacement Toeless Triplex DNA strands Reversible DNA circuit DNA walker

Multi-Task Visual Semantic Embedding Network for Image-Text Retrieval

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Journal of Computer Science & Technology 2024年第4期39卷 811-826页

作者： Xue-yang qin Li-Shuang Li Jing-Yao Tang Fei Hao Mei-Ling Ge Guang-Yao Pang School of Computer Science and Technology Dalian University of TechnologyDalian 116024China School of Computer Science Shaanxi Normal UniversityXi’an 710119China School of Computer Engineering Weifang UniversityWeifang 261061China Guangxi Colleges and Universities Key Laboratory of Intelligent Industry Software Wuzhou UniversityWuzhou 543002 China

Image-text retrieval aims to capture the semantic correspondence between images and texts,which serves as a foundation and crucial component in multi-modal recommendations,search systems,and online *** mainstream methods primarily focus on modeling the association of image-text pairs while neglecting the advantageous impact of multi-task learning on image-text *** this end,a multi-task visual semantic embedding network(MVSEN)is proposed for image-text ***,we design two auxiliary tasks,including text-text matching and multi-label classification,for semantic constraints to improve the generalization and robustness of visual semantic embedding from a training ***,we present an intra-and inter-modality interaction scheme to learn discriminative visual and textual feature representations by facilitating information flow within and between ***,we utilize multi-layer graph convolutional networks in a cascading manner to infer the correlation of image-text *** results show that MVSEN outperforms state-of-the-art methods on two publicly available datasets,Flickr30K and MSCOCO,with rSum improvements of 8.2%and 3.0%,respectively.

关键词： image-text retrieval cross-modal retrieval multi-task learning graph convolutional network

废科举前后翰林文人群体的自救活动与知识转型

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河南师范大学学报（哲学社会科学版） 2024年第3期51卷 113-119页

作者：杨芹中国政法大学刑事司法学院北京100088

清末十年,长久以来地位尊崇的翰林文人群体,受到新政持续冲击,面临“政”“学”双重危机。如何调适因应,找到新定位,实现转型,成为一大难题。为此,编纂新书、办讲习馆,皆是翰林文人群体持续不断的尝试和努力,可以视为他们的“自救活动... 详细信息

清末十年,长久以来地位尊崇的翰林文人群体,受到新政持续冲击,面临“政”“学”双重危机。如何调适因应,找到新定位,实现转型,成为一大难题。为此,编纂新书、办讲习馆,皆是翰林文人群体持续不断的尝试和努力,可以视为他们的“自救活动”。这些自救活动既往所知有限,现可通过深度解读翰林文人群体的文集、日记而揭示出来。这既反映了新政时期安置旧人的复杂较量,也展示了政治和文化格局剧变时代,旧精英群体寻找新定位和知识转型的艰难历程。

关键词：翰林文人群体清末新政孙家鼐恽毓鼎徐兆玮

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渣油加氢装置催化剂全蜡油硫化技术应用总结

炼油技术与工程 2024年第3期54卷 14-19页

作者：杨勤中石化湖南石油化工有限公司湖南省岳阳市414000

分析了固定床渣油加氢装置开工全部使用蜡油硫化方案的可行性。某公司首次采用全蜡油硫化对新鲜催化剂进行预硫化,全蜡油硫化可节省装置开工时间16 h,减少装置开工柴油使用量,减少产生不合格蜡油720 t,在低温硫化阶段蜡油硫化的上硫率更... 详细信息

分析了固定床渣油加氢装置开工全部使用蜡油硫化方案的可行性。某公司首次采用全蜡油硫化对新鲜催化剂进行预硫化,全蜡油硫化可节省装置开工时间16 h,减少装置开工柴油使用量,减少产生不合格蜡油720 t,在低温硫化阶段蜡油硫化的上硫率更高,硫化更均匀。对比分析了全蜡油硫化与分阶段硫化的催化剂性能,在工艺条件、原料性质基本相同的条件下,两种不同方式硫化后的催化剂杂质脱除率同样高,活性相当。使用全蜡油硫化的催化剂运行周期相对较长,说明全蜡油硫化催化剂的稳定性较高。全蜡油硫化具有操作简单、节约资源、还原活性好等优点,对于其他同类装置具有借鉴意义,为今后同类装置开工优化预硫化操作提供了宝贵经验。

关键词：渣油加氢装置氧化态催化剂预硫化全蜡油硫化脱硫率脱氮率脱残炭率