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Iron accumulation and its impact on osteoporotic fractures in postmenopausal women

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第4期24卷 301-311页

作者： Hui CAI Huimei zhang Weiting HE Heng Zhang Department of Pharmacy the First Affiliated Hospital of Bengbu Medical CollegeBengbu Medical CollegeBengbu 233004China School of Pharmacy Bengbu Medical CollegeBengbu 233030China School of Clinical Medicine Bengbu Medical CollegeBengbu 233030China Department of Orthopedics the First Affiliated Hospital of Bengbu Medical CollegeLaboratory of Tissue and Transplant in Anhui ProvinceBengbu Medical CollegeBengbu 233004China Department of Orthopedics Jinling HospitalSchool of MedicineNanjing UniversityNanjing 210002China

Postmenopausal osteoporosis is a kind of degenerative disease,also described as“invisible killer.”Estrogen is generally considered as the key hormone for women to maintain bone mineral content during their lives.Iron accumulation refers to a state of human serum ferritin that is higher than the normal value but less than 1000μg/L.It has been found that iron accumulation and osteoporosis could occur simultaneously with the decrease in estrogen level after menopause.In recent years,many studies indicated that iron accumulation plays a vital role in postmenopausal osteoporosis,and a significant correlation has been found between iron accumulation and fragility fractures.In this review,we summarize and analyze the relevant literature including randomized controlled trials,systematic reviews,and meta-analyses between January 1996 and July 2022.We investigate the mechanism of the effect of iron accumulation on bone metabolism and discuss the relationship of iron accumulation,osteoporosis,and postmenopausal fragility fractures,as well as the main clinical treatment strategies.We conclude that it is necessary to pay attention to the phenomenon of iron accumulation in postmenopausal women with osteoporosis and explore the in-depth mechanism of abnormal bone metabolism caused by iron accumulation,in order to facilitate the discovery of effective therapeutic targets for postmenopausal osteoporosis.

关键词： Iron accumulation Postmenopausal osteoporosis Bone metabolism Osteoporotic fracture

Double-decoupled inverse design of natural laminar flow nacelle under transonic conditions

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Chinese Journal of Aeronautics 2023年第6期36卷 1-18页

作者： Heng Zhang Jie LI Zhao YANG School of Aerospace Engineering Tsinghua UniversityBeijing 100084China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

The inverse design based on the pressure distribution is an essential approach to realize the improvement of Natural Laminar Flow(NLF) performance for nacelles. However, the direct definition of target pressure distribution at design point is challenging for the dilemma to consider the constraints of shock wave and laminar flow at the same time. In addition, the universality of method will be limited when the inverse design is strongly coupled with the solver. Thus, a double-decoupled methodology based on the relationship of pressure distributions between design and off-design points is proposed in this paper, which realizes the decoupling of constraints in shock wave and laminar flow on target pressure distribution as well as the decoupling of flow field solution and inverse design method. Aimed at an isolated flow-through-nacelle of high bypass ratio, the target pressure distribution with appropriate favorable gradient and shock-free feature is defined according to physical principles at the off-design point of Ma = 0.80 while the transonic and laminar performance are examined at the design point of Ma = 0.85. The solution of flow field is based on γ-Re_(θ) transition model and the inverse design is based on residual-correction method. With the inverse design starting from off-design point, the performance of shock wave and laminar flow at design point are both improved. The local shock wave after the lip of nacelle is eliminated effectively while the streamwise length of laminar flow region is doubled and exceeds to 30% of the chord length. The percentage of drag reduction for outboard surface is 12.7% for friction drag, 7.8%for pressure drag and 10.5% for total drag. The effects of inverse design on the process of transition are analyzed with detailed flow features. The robustness of laminar flow is examined under different variation factors of freestream which are deviated from the design point.

关键词： Drag reduction Inverse design method Nacelle Natural laminar flow Transonic

Source free unsupervised domain adaptation for electro-mechanical actuator fault diagnosis

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Chinese Journal of Aeronautics 2023年第4期36卷 252-267页

作者： Jianyu WANG Heng Zhang Qiang MIAO College of Electrical Engineering Sichuan UniversityChengdu 610065China

A common necessity for prior unsupervised domain adaptation methods that can improve the domain adaptation in unlabeled target domain dataset is access to source domain data-set and target domain dataset simultaneously.However,data privacy makes it not always possible to access source domain dataset and target domain dataset in actual industrial equipment simulta-neously,especially for aviation component like Electro-Mechanical Actuator(EMA)whose dataset are often not shareable due to the data copyright and confidentiality.To address this problem,this paper proposes a source free unsupervised domain adaptation framework for EMA fault diagnosis.The proposed framework is a combination of feature network and classifier.Firstly,source domain datasets are only applied to train a source model.Secondly,the well-trained source model is trans-ferred to target domain and classifier is frozen based on source domain hypothesis.Thirdly,nearest centroid filtering is introduced to filter the reliable pseudo labels for unlabeled target domain data-set,and finally,supervised learning and pseudo label clustering are applied to fine-tune the trans-ferred model.In comparison with several traditional unsupervised domain adaptation methods,case studies based on low-and high-frequency monitoring signals on EMA indicate the effectiveness of the proposed method.

关键词： Data privacy Electro-mechanical actuator Pseudo-label clustering Nearest centroid filtering Unsupervised domain adaptation

Active DNA demethylation in plants:20 years of discovery and beyond

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Journal of Integrative Plant Biology 2022年第12期64卷 2217-2239页

作者： Heng Zhang Zhizhong Gong Jian-Kang Zhu State Key Laboratory of Molecular Plant Genetics Shanghai Centre for Plant Stress BiologyCentre for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai200032 China State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing100193 China School of Life Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaoding071002 China School of Life Sciences Institute of Advanced BiotechnologySouthern University of Science and TechnologyShenzhen518055 China

Maintaining proper DNA methylation levels in the genome requires active demethylation of DNA.However,removing the methyl group from a modified cytosine is chemically difficult and therefore,the underlying mechanism of demethylation had remained unclear for many years.The discovery of the first eukaryotic DNA demethylase,Arabidopsis thaliana REPRESSOR OF SILENCING 1(ROS1),led to elucidation of the 5-methylcytosine base excision repair mechanism of active DNA demethylation.In the 20 years since ROS1 was discovered,our understanding of this active DNA demethylation pathway,as well as its regulation and biological functions in plants,has greatly expanded.These exciting developments have laid the groundwork for further dissecting the regulatory mechanisms of active DNA demethylation,with potential applications in epigenome editing to facilitate crop breeding and gene therapy.

关键词： abiotic stress response base excision repair DNA demethylation DNA methylation histone modification plant growth and development plant microbe interaction

Overriding the inherent alkalinity to dual phosphinito bimetallic catalyst for C(sp^(2))-C(sp^(3))formation:A combined computational and experimental study

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中国化学快报:英文版 2023年第8期34卷 147-152页

作者： Sujuan Zheng Heng Zhang Qian Peng State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformation Tianjin 300192China

Unraveling the catalytic reaction mechanism is a long-term challenge for developing efficient catalysts.The blooming bimetallic catalyst have enabled to activate inert bonds and realize complex C-C formation.Herein,we theoretically discover a dual-phosphinito bridged hetero-bimetallic species that verified by NMR experiments.Our results indicate only dual-phosphinito Ni-Al model can be an active catalyst in asymmetric cycloadditions via C-C activation and C-H activation,which can well rationalize the experimental observations for both reactivity and stereo-selectivity.An unprecedented tandem redox dehydrogenation mechanism was revealed to control the formation of this active species overriding the inherent basicity.Synergistic Lewis acid and eg orbital interactions,including dz2 orbital reoccupation and d_(x^(2)−y^(2))orbital recombination,were disclosed to understand both thermodynamic and kinetic advance of dual-bridged model,displaying feasible redox properties.

关键词： Ni-Al bimetallic catalysis Secondary phosphine oxides Redox dehydrogenation Dual-SPO model

Expedient Trifluoromethylacylation of Styrenes Enabled by Photoredox Catalysis

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Chinese Journal of Chemistry 2022年第1期40卷 59-64页

作者： Lu Wang Heng Zhang Chuan Zhu Chao Feng Technical Institute of Fluorochemistry(TIF) Institute of Advanced Synthesis(IAS)School of Chemistry and Molecular EngineeringNanjing Tech University30 South Puzhu RoadNanjingJiangsu 211816China

Herein,we disclosed a photoredox enabled protocol for trifluoromethylacylation of styrenes through a radical-carboanion cascade and subsequent oxidation.With a broad range of aldehydes and inexpensive Langlois reagent as acyl and CF3 precursor,respectively,the alkene motif could be readily converted into β-trifluoromethyl ketones in moderate to good yields and with excellent regioselectivity.Besides CF3,di-,mono-and non-fluorinated C-radicals were revealed amenable in this reaction,providing good opportunity for the construction of structurally diverse ketones of interest in pharmaceutical research.Additionally,the utility of this protocol was further demonstrated by successful extension to trifluoromethylarylation and-alkylation by employing arylcyanide or acrylates in place of carbonyls.

关键词： Trifluoromethylacylation Alkenes Photocatalysis CF_(3)radical Radical-polar crossover

One-pot hydrothermal synthesis of hierarchical porous manganese silicate microspheres as excellent Fenton-like catalysts for organic dyes degradation

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Nano Research 2022年第4期15卷 2977-2986页

作者： Yuyu Zheng Lihua Wang Liyun zhang Heng Zhang Wancheng Zhu Department of Chemical Engineering Qufu Normal UniversityQufu 273165China

Towards bottlenecks demonstrated by typical Fenton-like catalysts in advanced oxidation processes(AOPs)for wastewater treatment,novel hierarchical porousMn^(2+)Mn_(6)^(3+)SiO_(12)(Mn_(7)SiO_(12),MSO-12)microspheres(specific surface area:434.90 m^(2)·g^(-1),pore volume:0.78 cm^(3)·g^(-1))were rationally designed and achieved via a simple one-pot hydrothermal method(150℃ and 12.0 h)without any pre-prepared templates or organic solvents,by using abundant MnCl_(2)·4H_(2)O and Na_(2)SiO_(3)·9H_(2)O as the basic raw materials.The MSO-12 microspheres are confirmed as high-efficiency Fenton-like catalysts for degradation of organic dyes(methylene blue(MeB),Rhodamine B(RhB),and methyl blue(MB))in the presence of H_(2)O_(2),with impressively high specific consumption amount of MeB(R=12.35 mg·g^(-1)·min^(-1))and extremely low leaching of Mn(Mnloss%=0.27%).Simultaneously,the synergetic effect of adsorption and degradation on the superior removal of MeB is uncovered.The excellent recycling performances,especially the satisfactory removal of MeB from the actual water bodies(e.g.,tap water and river water),as well as potential applications for degradation of RhB and MB enable the MSO-12 microspheres as a novel promising competitive candidate Fenton-like catalyst.

关键词： hierarchical porous manganese silicate microspheres Fenton-like catalysts degradation organic dyes

农业生产性服务、农业技术进步与农民增收——基于中介效应与面板门槛模型的分析

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农业现代化研究 2021年第4期42卷 652-663页

作者：张恒郭翔宇东北农业大学经济管理学院黑龙江哈尔滨150036

探讨农业生产性服务业发展对农民增收的作用机制与约束条件,对农业生产性服务业发展水平提高、农业技术成果转化和农民增收具有重要意义。基于2009—2018年的省级面板数据,运用中介效应模型,对农业生产性服务、农业技术进步和农民收入... 详细信息

探讨农业生产性服务业发展对农民增收的作用机制与约束条件,对农业生产性服务业发展水平提高、农业技术成果转化和农民增收具有重要意义。基于2009—2018年的省级面板数据,运用中介效应模型,对农业生产性服务、农业技术进步和农民收入之间的作用逻辑进行研究,建立以人均经营土地规模为门槛变量的面板门槛模型,探讨农业生产性服务对农民增收的非线性影响。结果表明,农业生产性服务与农业技术进步均正向影响农民收入,对工资性收入的提升效果强于对经营性收入的提升效果。农业技术进步为农业生产性服务与农民增收之间的中介变量,中介效应为4.5%,农业技术进步的中介作用在粮食主销区中最大,远远高于主产区和产销平衡区。通过农业生产性服务实现的技术进步更容易提高农业经营性收入;整体上,农业生产性服务对农民增收的影响表现为非线性,随着人均经营土地规模的扩大,农业生产性服务对农民总收入与工资性收入提升呈现出边际效应递增的规律,而服务对经营性收入的提升不受土地经营规模的影响。尤其在粮食主产区,当人均经营土地规模跨过一定门槛后,更有利于农业生产性服务增收效应的发挥。因此,目前应将农业生产性服务业的发展重点放在粮食主产区与产销平衡区,进一步重视并充分发挥农业生产性服务促进农业科技成果转化为生产力的能力,加强服务的技术支持,尤其是劳动替代性技术的引入,通过土地经营权流转与全程托管等形式的规模经营来缓解人多地少对农业生产性服务充分发挥作用的制约。

关键词：农业生产性服务农业技术进步农民增收粮食产销区中介效应模型面板门槛模型

Achieving Physical Layer Security Against Location Unknown Eavesdroppers via Friendly Jammer

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自动化学报:英文版 2023年第10期10卷 2038-2040页

作者： Heng Zhang Jianwei Sun Xin Wang Chenglong Gong School of Computer Engineering Jiangsu Ocean UniversityLianyungang 222000China School of Electronic Engineering Jiangsu Ocean UniversityLianyungang 222000China Shandong Provincial Key Laboratory of Computer Networks Shandong Computer Science CenterQilu University of TechnologyJinan 250014China

Dear Editor, This letter is concerning friendly jamming unmanned aerial vehicles(UAVs) to assist in the safe communication of UAV base stations. Due to the openness of UAV wireless communication, it is vulnerable to attacks leading to information disclosure or blockage. To address this issue, friendly jamming UAVs can assist UAV base stations and improve the security of wireless communications.

关键词： communication letter base