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Science China Chemistry 2024年第10期67卷 3397-3405页

作者： Yidan Xing Rongrong Yu Mingdong Jiao ting wang Xianjie Fang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical EngineeringShanghai Jiao Tong University Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Key Laboratory of Organosilicon Material Technology of Zhejiang ProvinceCollege of MaterialChemistry and Chemical EngineeringHangzhou Normal University

The transition-metal-catalyzed migratory functionalization has emerged as a robust protocol for the building of C–C bonds remote from the “initiation” position. However, a similar strategy for the construction of quaternary carbon centers is still underdeveloped and only a limited number of reports exist. Herein, we report a nickel-catalyzed migratory hydrocyanation of unconjugated dienes to construct remote cyano-substituted quaternary carbon centers. This transformation features exceptional regioselectivity, mild reaction conditions, broad substrate scope and high yields. The synthetic utility of this method has been highlighted by a series of product derivatizations, and the potential of this transformation has been extended to synthesize TRPV1 antagonist and the key intermediate in the total synthesis of quebrachamine. Density functional theory(DFT) studies unveiled that the specific catalytic pocket assumed a significant role in the selective formation of cyano-substituted quaternary carbon centers.

关键词： chain-walking regioselectivity remote cyanation quaternary carbon centers unconjugated dienes

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基于改进凸分解的手势识别

北京理工大学学报 2018年第3期38卷 279-285页

作者：潘志庚王顺婷姚争为杭州师范大学数字媒体与人机交互研究中心浙江杭州311121

提出了一种新的基于Kinect的实时静态手势识别方法,主要贡献包括:提出了一种简易可行的、结合图像深度信息与肤色信息的手势区域检测与分割方法;提出了一种改进的凸分解算法,对手势区域进行近似凸形状分解,以得到表征手势特征的骨架信息... 详细信息

提出了一种新的基于Kinect的实时静态手势识别方法,主要贡献包括:提出了一种简易可行的、结合图像深度信息与肤色信息的手势区域检测与分割方法;提出了一种改进的凸分解算法,对手势区域进行近似凸形状分解,以得到表征手势特征的骨架信息;采用基于路径相似性的骨架图匹配算法对手势进行匹配以实现识别.针对特定手势集进行了对比实验,实验结果表明,本文方法在识别结果的准确率以及算法的效率上都有着良好的表现.

关键词：手势识别凸分解骨架图匹配深度信息

Epigenetics and environmental health

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FRONTIERS OF MEDICINE 2024年第4期18卷 571-596页

作者： Zhang, Min Hu, ting Ma, Tianyu Huang, Wei wang, Yan Chinese Acad Med Sci & Peking Union Med Coll Natl Canc Ctr Key Lab Canc & Microbiome State Key Lab Mol OncolNatl Clin Res Ctr CancCan Beijing 100021 Peoples R China Capital Med Univ Sch Basic Med Sci Dept Biochem & Mol Biol Beijing Key Lab Canc Invas & Metastasis Res Beijing 100069 Peoples R China

Epigenetic modifications including DNA methylation, histone modifications, chromatin remodeling, and RNA modifications complicate gene regulation and heredity and profoundly impact various physiological and pathological processes. In recent years, accumulating evidence indicates that epigenetics is vulnerable to environmental changes and regulates the growth, development, and diseases of individuals by affecting chromatin activity and regulating gene expression. Environmental exposure or induced epigenetic changes can regulate the state of development and lead to developmental disorders, aging, cardiovascular disease, Alzheimer's disease, cancers, and so on. However, epigenetic modifications are reversible. The use of specific epigenetic inhibitors targeting epigenetic changes in response to environmental exposure is useful in disease therapy. Here, we provide an overview of the role of epigenetics in various diseases. Furthermore, we summarize the mechanism of epigenetic alterations induced by different environmental exposures, the influence of different environmental exposures, and the crosstalk between environmental variation epigenetics, and genes that are implicated in the body's health. However, the interaction of multiple factors and epigenetics in regulating the initiation and progression of various diseases complicates clinical treatments. We discuss some commonly used epigenetic drugs targeting epigenetic modifications and methods to prevent or relieve various diseases regulated by environmental exposure and epigenetics through diet.

关键词： epigenetics environmental exposure health prevention and therapy DNA-METHYLATION HISTONE MODIFICATION OXIDATIVE STRESS NONCODING RNAS BLOOD-PRESSURE EXPOSURE CANCER CELLS GENE MICROBIOTA

Deciphering dynamic surface of PtRu alloy nanocatalysts to revisit their synergistic effects during the electrooxidation

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Science China Chemistry 2024年第7期67卷 2224-2233页

作者： Xiao-Chong Li Bo wang Zhou Yu Qiang Wan Ju-Fang Zheng Emmanuel Maisonhaute Xiao-shun Zhou Ya-Hao wang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China Laboratoire Interface et Systèmes Electrochimiques CNRS UMR 8235Sorbonne UniversitéF-75252 Paris cedex 5France

Correlating dynamic structural transformation of catalysts with the surface intermediate species under operating conditions is critical for updating the understanding of structure–performance ***,we probe the electrochemical potentialdependent surface structures and adsorbed intermediates on PtRu binary alloy nanocatalysts to revisit its synergistic mechanisms for CO electrooxidation enhanced ***-situ spectral characteristics by using modified shell-isolated nanoparticle-enhanced Raman spectroscopy,show that in acidic solution,when the potential is positively scanned from 0.1 V to 1.5 V relative to reversible hydrogen electrode(RHE),the surface of the alloy catalyst evolves from metallic PtRu to adsorbed oxygen gradually covering and accumulating on Ru sites(denoted as PtRuO_(x),x≤2),forming segregated RuO_(2),and finally forming a threedimensional oxide layer(denoted as 3D PtRuO_(4)).Moreover,molecular evidence associated with periodic density functional theory calculations reveals that electronic effects promote ruthenium to become more oxidizable and *** particular,we found here that ^(*)O and ^(*)OH at surface RuO_(x) sites are highly efficient CO oxidation active species in comparison to the same entities adsorbed on metallic Ru *** work sheds light on the complex surface dynamic process of practical Pt-based binary nanocatalysts and improves the understanding of synergistic mechanism for the development of fuel cell devices.

关键词： in-situ Raman spectroscopy surface evolution bifunctional mechanism PtRu electrooxidation

Tbx 4 and Tbx 5 gene expression associated with appendage development and its relationship with the absence of the pelvic fin in Pampus argenteus

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Journal of Oceanology and Limnology 2024年第2期42卷 580-593页

作者： shun ZHANG Xiaojing ZHU Lingzhu HU Kai LIAO Shanliang XU Danli wang Chunyang GUO School of Marine Science Ningbo UniversityNingbo 315211China Key Laboratory of Applied Marine Biotechnology Ningbo UniversityChinese Ministry of EducationNingbo 315211China

The Tbx family is first known through the study of their functions in the body and limbs,and its members Tbx4 and Tbx5 genes are important factors in determining the characteristics of the *** argenteus is one of the important economical marine fishes widely distributed in offshore ***,it is necessary to study the role of Tbx family genes in the deletion of pelvic fin in *** this study,we cloned Tbx4 and Tbx5 cDNA sequence of ***(GenBank:MH709128 and MH712458).The Western blot and real time PCR were used to detect the expressions of Tbx4 and Tbx5 in different developmental stages and tissues of *** addition,whole-mount in-situ hybridization was used to study the localization of Tbx4 and Tbx5 genes in different developmental stages of *** show that the translation of Tbx4 mRNA was inhibited during the critical period of pelvic fin *** different tissues,Tbx4 protein levels were the lowest in the abdominal epithelium,and even lower than that in the pectoral fin,suggesting that the protein expression was also inhibited in the abdominal epithelium of adult ***,the results indicated that upstream genes regulation led to the key stage-specific and low expression of Tbx4 during pelvic fin development and in the abdominal epithelium.

关键词： Stromateidae pelvic fin protein translation T-box aquaculture broodstock

The effects of deformation parameters and cooling rates on the aging behavior of AZ80+0.4%Ce

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Journal of Magnesium and Alloys 2024年第2期12卷 639-658页

作者： Yongbiao Yang Jinxuan Guo Cuiying wang ting Yan Zhang Wenxuan Jiang Zhimin Zhang Qiang wang Guojun Li Jun wang College of Materials Science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxiChina030051 State Key Laboratory of Advanced Stainless Steel Materials Taiyuan Iron Steel(Group)Co.Ltd.Taiyuan 030003China Technology Center Shanxi Taigang Stainless Steel Co.Ltd.Taiyuan 030003China

The extruded AZ80+0.4%Ce magnesium alloy was twisted in the temperature range of 300-380℃by using a Gleeble 3500 thermal simulation test machine with a torsion *** deformed cylindrical specimens were cooled at a cooling rate of 10℃/s or 0.1℃/s,respectively,and aged at 170℃.The microstructure analysis results showed that the grain size decreased with increasing specimen radial position from center(SRPC),and that the strong initial basal texture of the extruded magnesium alloy was *** continuous and discontinuous dynamic recrystallization mechanisms were involved in contributing to the grain refinement for all specimens *** a novel extension twinning induced dynamic recrystallization mechanism was proposed for specimen deformed at 300℃.For the specimens deformed at 300℃and 340℃followed by a slow cooling rate(0.1℃/s),precipitates of various shapes(β-Mg_(17)Al_(12)),with the dominant precipitates being on the grains boundaries,appeared on the surface *** specimen deformed at 380℃,lamellar precipitates(LPS)in the interiors of the grains were *** aging,the LPS still dominated for specimens twisted at 380℃;however,the LPS gradually decreased with decreasing deformation temperatures from 380℃to 300℃.Dynamically precipitatedβ,especially those decorating the grain boundaries,changed the competition pictures for the LPS and precipitates of other shapes after ***,LPS dominated the areas for the center section of the specimens after aging regardless of deformation *** temperature deformation with high SRPC followed by rapid cooling rate increased the micro hardness of the alloy after aging due to refined grain,reduced precipitates size,decreased lamellar spacing as well as strain hardening.

关键词： AZ80+0.4%Ce magnesium alloy Hot torsion Deformation parameters Cooling rate Aging Micro hardness

Effect of BaO and MgO on structure and properties of aluminate slag with various CaO/Al_(2)0_(3)ratios

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Journal of Iron and Steel Research International 2024年第1期31卷 204-214页

作者： Yu-qi Kong ting Wu Wen-zhi Xia Wen Yang Hai-chuan wang School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction and Resource Recycling(Ministry of Education) Anhui University of TechnologyMa’anshan243002AnhuiChina

To provide theoretical guidance for performance stability control of low-reactive mold fluxes,the effects of BaO and MgO on the structure and properties of aluminate slag with various CaO/Al_(2)0_(3)(C/A)ratios were investigated using the Fourier transform infrared spectrometer,Raman spectroscope,hemispherical melting point instrument,rotational viscometer and X-ray *** results indicated that with BaO and MgO addition,the structure polymerization was first weakened and then enhanced at C/A of 1.1,and the transition contents corresponded to 8 wt.%BaO and 2 wt.%MgO,respectively,while the structure polymerization decreased continuously at C/A of *** the viscosity change was well consistent with the structure evolution,the polymerization degree played a more prominent role in the slag viscosity than superheat degree when the melting temperature difference was within 40℃.The break temperature decreased initially and then increased with augment of BaO and MgO at C/A of 1.1,while it manifested a decrease trend with BaO addition,and it decreased obviously but then turned to increase with MgO increment at C/A of *** crystallization phase and crystallization ratio kept stable with BaO increment,while the crystallization ratio rose greatly with MgO promoting LiAlO_(2)precipitation at C/A of *** crystal types of all experimental slags were mainly Ca_(12)Al_(14)O_(33)and CaF_(2)at C/A of 1.3,and the precipitation of crystalline phase BaAl2O4 demonstrated a rising trend,while that of Ca_(12)Al_(14)O_(33)gradually declined with BaO augment.

关键词： Aluminate slag Structure MgO BaO Viscosity Property

Bioengineered skin organoids:from development to applications

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Military Medical Research 2024年第3期11卷 449-466页

作者： Zi-Xuan Hong shun-Tian Zhu Hao Li Jing-Zhi Luo Yu Yang Yang An Xi wang Kai wang Department of Physiology and Pathophysiology School of Basic Medical SciencesState Key Laboratory of Vascular Homeostasis and RemodelingPeking UniversityBeijing 100191China Department of Hepatopancreatobiliary Surgery the Third Affiliated Hospital of Soochow UniversityChangzhou 213000JiangsuChina Department of Plastic Surgery Peking University Third HospitalBeijing 100191China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China State Key Laboratory of Cardiovascular Disease Fuwai HospitalBeijing 100037China Beijing Key Laboratory of Metabolic Disorder Related Cardiovascular Disease Capital Medical UniversityBeijing 100050China

Signifcant advancements have been made in recent years in the development of highly sophisticated skin *** as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex structures and are increasingly recognized as efective alternatives to traditional culture models and human skin due to their ability to overcome the limitations of two-dimensional(2D)systems and ethical *** inherent plasticity of skin organoids allows for their construction into physiological and pathological models,enabling the study of skin development and dynamic *** review provides an overview of the pivotal work in the progression from 3D layered epidermis to cyst-like skin organoids with ***,it highlights the latest advancements in organoid construction facilitated by state-of-the-art engineering techniques,such as 3D printing and microfuidic *** review also summarizes and discusses the diverse applications of skin organoids in developmental biology,disease modelling,regenerative medicine,and personalized medicine,while considering their prospects and limitations.

关键词： Skin organoid Organoid generation Skin appendage Tissue engineering Disease modelling Regenerative medicine

In vitro performance of a biodegradable zinc alloy adjustable-loop cortical suspension fixation for anterior cruciate ligament reconstruction

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 887-898页

作者： ting wang Zhangzhi Shi Hongyong Zhong Xiangmin Li Jinling Sun Wei Yin Xiaojing Ji Qiang wang Anqi Zhao Luning wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Anterior cruciate ligament(ACL)injuries of the knee are one of the most common and serious athletic *** widely used cortical suspension fixation buttons for ligament reconstruction are permanent implants,particularly those made from conventional steel or titanium *** this study,a biodegradable Zn-0.45Mn-0.2Mg(ZMM42)alloy with the yield strength of 300.4 MPa and tensile strength of 329.8 MPa was prepared through hot *** use of zinc alloys in the preparation of cortical suspension fixation buttons was proposed for the first *** 35 d of immersion in simulated body fluids,the ZMM42 alloy fixation buttons were degraded at a rate of 44μm/a,and the fixation strength was retained(379.55 N)in the traction ***,the ZMM42 alloy fixation buttons exhibited an increase in MC3T3-E1 cell viability and high antibacterial activity against Escherichia coli and Staphylococcus *** results reveal the potential of biodegradable zinc alloys for use as ligament reconstruction materials and for developing diverse zinc alloy cortical suspension fixation devices.

关键词： anterior cruciate ligament reconstruction zinc alloy fixation buttons mechanical property corrosion behavior biocompatibility

Efficient electroreduction of nitrate via enriched active phases on copper-cobalt oxides

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Chinese Chemical Letters 2024年第4期35卷 204-209页

作者： Ling Fang Sha wang shun Lu Fengjun Yin Yujie Dai Lin Chang Hong Liu Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China

Electrochemical conversion of nitrate(NO_(3)~-) to ammonia(NH_(3)) can target two birds with one stone well, in NO_(3)^(-)-containing sewage remediation and sustainable NH_(3) production. However, single metalbased catalysts are difficult to drive high-efficient NO_(3)~- removal due to the multi-electron transfer ***, we present a tandem catalyst with simple structure, Cu-Co binary metal oxides(Cu-Co-O), by engineering intermediate phases as catalytic active species for NO_(3)~- conversion. Electrochemical evaluation,X-ray photoelectron spectroscopy, and in situ Raman spectra together suggest that the newly-generated Cu-based phases was prone to NO_(3)~- to NO_(2)~- conversion, then NO_(2)~- was reduced to NH_(3) on Co-based species. At an applied potential of -1.1 V vs. saturated calomel electrode, the Cu-Co-O catalyst achieved NO_(3)~- -N removal of 90% and NH_(3) faradaic efficiency of 81% for 120 min in 100 m L of 50 mg/L NO_(3)~- -N,consuming only 0.69 k Wh/mol in a two-electrode system. This study provides a facile and efficient engineering strategy for developing high-performance catalysts for electrocatalytic nitrate conversion.

关键词： NO_(3)^(-)-containing sewage remediation Electrocatalytic reduction Copper-cobalt oxides Tandem reactivity Enriched active phases