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Direct enantioselective reduction of C=C bond of β-polyfluoro-alkylated enones via asymmetric photoredox catalysis

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Science China Chemistry 2024年第6期67卷 2016-2021页

作者： Linghong Zhang Jin Ma Xu Ban Xiaowei Zhao Yanli Yin Zhiyong Jiang Key Laboratory of Natural medicine and Immuno-Engineering of henan Province Henan UniversityKaifeng475004China school of Chemistry and Chemical Engineering Henan Normal UniversityPingyuan LaboratoryXinxiang453007China College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou450001China

Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric ***,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the ***,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.

关键词： photoredox catalysis Br?nsted acids asymmetric reduction enantioselective protonation azaarenes

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao Lin Cheng He school of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

MULTIRATE TIME ITERATIVE SCHEME WITH MULTIPHYSICS FINITE ELEMENT METHOD FOR A NONLINEAR POROELASTICITY

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Journal of Computational Mathematics 2024年第2期42卷 597-616页

作者： Zhihao Ge Hairun Li Tingting Li school of Mathematics and Statistics Henan UniversityKaifengHenan 475004China

In this paper,a multirate time iterative scheme with multiphysics finite element method is proposed and analyzed for the nonlinear poroelasticity *** original problem is reformulated into a generalized nonlinear Stokes problem coupled with a diffusion problem of a pseudo pressure field by a new multiphysics approach.A multiphysics finite element method is adopted for the spatial discretization,and the generalized nonlinear Stokes problem is solved in a coarse time step and the diffusion problem is solved in a finer time *** proposed algorithm is a decoupled algorithm,which is easily implemented in computation and reduces greatly computation *** stability analysis and the convergence analysis for the multirate iterative scheme with multiphysics finite element method are *** numerical tests are shown to demonstrate and validate the analysis results.

关键词： Nonlinear poroelasticity model Multiphysics finite element method Multirate iterative scheme

Semisymmetric Graphs of Order 2p^(3)with Valency p^(2)

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Algebra Colloquium 2024年第2期31卷 199-208页

作者： Li Wang Songtao Guo Genghua Fan school of Mathematics and Information Science Henan Polytechnic University JiaozuoHenan 454000China school of Mathematics and Statistics Henan University of Science and Technology LuoyangHenan 471023China 不详

A simple undirected regular graph is said to be semisymmetric if it is edge-transitive but not *** a semisymmetric graphΓof order 2p^(3),p a prime,it is well known thatΓis bipartite with two biparts having equal *** complete classification of such graphs has been given for the full automorphism group Aut(Γ)acting unfaithfully on at least one bipart ofΓ,which shows that there is only one infinite family of such graphs with valency p^(2).The graphs of this kind have been determined when Aut(Γ)acts faithfully and primitively on at least one bipart ofΓ,and thus there is only one remaining case for classifying such graphs of valency p^(2),Aut(Γ)acting faithfully and imprimitively on both biparts ofΓ,which is dealt with in this *** a result,there is only one infinite family of semisymmetric graphs of order 2p^(3)with valency p^(2).

关键词： semisymmetric graph semitransitive graph bi-coset graph

Suppressor tRNA in gene therapy

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Science China(Life Sciences) 2024年第10期67卷 2120-2131页

作者： Jingjing Ruan Xiaoxiao Yu Huixia Xu Wenrui Cui Kaiye Zhang Chenyang Liu Wenlong Sun Xiaodan Huang Lei An Yue Zhang The Children's Hospital National Clinical Research Center for Child HealthZhejiang University School of MedicineLiangzhu LaboratoryHangzhou 310000China Liangzhu Laboratory Zhejiang University School of MedicineHangzhou 311121China Department of Thoracic and Cardiovascular Surgery Huaihe Hospital of Henan UniversityHenan UniversityKaifeng 475000China Translational medicine Center Huaihe Hospital of Henan UniversityHenan UniversityKaifeng 475000China Eye Center The Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China

Suppressor tRNAs are engineered or naturally occurring transfer RNA molecules that have shown promise in gene therapy for diseases caused by nonsense mutations,which result in premature termination codons(PTCs)in coding sequence,leading to truncated,often nonfunctional *** t RNAs can recognize and pair with these PTCs,allowing the ribosome to continue translation and produce a full-length *** review introduces the mechanism and development of suppressor t RNAs,compares suppressor tRNAs with other readthrough therapies,discusses their potential for clinical therapy,limitations,and *** also summarize the applications of suppressor tRNAs in both in vitro and in vivo,offering new insights into the research and treatment of nonsense mutation diseases.

关键词： suppressor tRNA PTC nonsense mutation readthrough gene therapy

Interplay between mesenchymal stem cells and macrophages:Promoting bone tissue repair

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World Journal of Stem Cells 2024年第4期16卷 375-388页

作者： Fei-Fan Zhang Yang Hao Kuai-Xiang Zhang Jiang-Jia Yang Zhi-Qiang Zhao Hong-Jian Liu Ji-Tian Li Molecular Biology Lab Henan Luoyang Orthopedic Hospital(Henan Provincial Orthopedic Hospital)Zhengzhou 450000Henan ProvinceChina Graduate school Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Graduate school Henan University of Chinese MedicineZhengzhou 450046Henan ProvinceChina Department of Orthopaedics The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

The repair of bone tissue damage is a complex process that is well-orchestrated in time and space,a focus and difficulty in orthopedic *** recent years,the success of mesenchymal stem cells(MSCs)-mediated bone repair in clinical trials of large-area bone defects and bone necrosis has made it a candidate in bone tissue repair engineering and regenerative *** are closely related to *** one hand,MSCs regulate the immune regulatory function by influencing macrophages proliferation,infiltration,and phenotype polarization,while also affecting the osteoclasts differentiation of *** the other hand,macrophages activate MSCs and mediate the multilineage differentiation of MSCs by regulating the immune *** cross-talk between MSCs and macrophages plays a crucial role in regulating the immune system and in promoting tissue *** full use of the relationship between MSCs and macrophages will enhance the efficacy of MSCs therapy in bone tissue repair,and will also provide a reference for further application of MSCs in other diseases.

关键词： Bone tissue damage Inflammation Macrophages Mesenchymal stem cells Tissue regeneration

Facile interfacial synthesis of gold micronails with adjustable length and roughness and their superior SERS properties for the detection of p-aminothiophenol Author links open overlay panel

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Particuology 2024年第8期91卷 333-340页

作者： Hang Li Kaisheng Yao Tianhang Liu Weiwei Lu school of Chemistry and Chemical Engineering Henan University of Science and TechnozlogyLuoyang471023China school of Physics and Engineering Henan University of Science and TechnologyLuoyang471023China

Au hierarchical architectures with special morphology and structures are strongly desired in varied ***,a simple synthesis method was developed for the one-step preparation of Au micronails(MNs)at the planar liquid-liquid interface under mild *** well-defined Au MNs were grown and constructed at CHCl_(3)-H_(2)O interface at room temperature using aniline in CHCl_(3)as reducing agent and HAuCl_(4)in H_(2)O as precursor and no surfactant or seed is *** intriguing Au MNs with rough surface consist of big heads and thin rods,just like iron nails in ***,through simple changing the reagent concentrations,the length and surface roughness of Au MNs can be adjusted *** effects of a series of factors on the morphology and structure of the products are studied in *** p-aminothiophenol as a molecular probe,the as-obtained Au MNs all exhibit dramatically improved surface enhanced Raman scattering sensitivity and high reproducibility,the enhancement factor and limit of detection of Au MNs are 5.4×10^(5)and 1.0×10^(-10),respectively.

关键词： Au micronails Liquid-liquid interface synthesis Surface enhanced Raman scattering P-aminothiophenol

Efficacy of scraping therapy on blood pressure and sleep quality in stage Ⅰ and Ⅱ essential hypertension: A systematic review and meta-analysis

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Journal of Integrative medicine 2024年第1期22卷 12-21页

作者： Zheng-gang Zhu Jian-ru Wang Xiao-yan Pan school of Nursing Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina school of Health Sciences Universiti Sains MalaysiaKubang Kerian 16150KelantanMalaysia Department of Cardiovascular medicine the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

Background Scraping therapy is widely used in treating stage I and II essential hypertension in ***,there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential *** strategy Seven electronic databases(PubMed,Scopus,Cochrane Library,Web of Science,EBSCO,China National Knowledge Infrastructure and Wanfang Data electronic databases)were searched from inception to December *** on the principle of combining subject words with text words,the search strategy was constructed around search terms for“scraping therapy,”“scraping,”“Guasha,”“Gua sha,”“hypertension,”and“high blood pressure”during the database *** criteria Randomized controlled trials(RCTs)were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy *** intervention group received antihypertensive drugs and scraping therapy,while the control group only took antihypertensive *** extraction and analysis Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the *** quality of the selected RCTs was assessed using the PEDro *** sensitivity analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify any studies with greater influence on the *** analysis was performed to find the source of *** plots were used to evaluate the publication bias of included *** Nine RCTs including 765 participants were ***-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure(mean difference[MD]=?5.09,95%confidence interval[CI]=?6.50 to?3.67,P<0.001)and diastolic blood pressure(MD=?2.66,95%CI=?3.17 to?2.14,P<0.001).Subgroup analysis showed tha

关键词： Scraping therapy Essential hypertension Efficacy Blood pressure Sleep quality Systematic review Meta-analysis

Enhancing electromagnetic wave absorption with core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres

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Carbon Energy 2024年第8期6卷 90-104页

作者： Xuewen Jiang Qian Wang Limeng Song Hongxia Lu Hongliang Xu Gang Shao Hailong Wang Rui Zhang Changan Wang Bingbing Fan school of Material Science and Engineering Zhengzhou UniversityZhengzhouHenanChina henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhouHenanChina school of Materials Science and Engineering Tsinghua UniversityBeijingChina

Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of *** alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)*** architecture,comprising SiO_(2)as the core,MXene as the intermediate layer,and MoS_(2)as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal *** complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2)***,the synergistic combination of SiO_(2)and MoS_(2)with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance ***,the core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 *** work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.”

关键词： core‐shell structure electromagnetic wave absorption multiloss mechanism SiO_(2)@MXene@MoS_(2)