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The role of antioxidant system in freezing acclimation-induced freezing resistance of Populus suaveolens cuttings

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Forestry Studies in China 2007年第2期9卷 107-113页

作者： Luo Lei Lin Shan-zhi zheng hui-quan Lei Yang Zhang Qian Zhang zhi-yi Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants Ministry of Education Beijing Forestry UniversityBeijing 100083 P. R. China

We investigated the changes in the contents of H202, malonaldehyde （MDA） and endogenous antioxidants, the activities of protective enzymes and some critical enzymes involved in the ascorbate-glutathione （ASA-GSH） cycle as well as freezing resistance （expressed as LT50） and correlations mentioned above, in detail using Populus suaveolens cuttings. The purpose was to explore the physiological mechanism of the enhancement of freezing resistance induced by freezing acclimation at -20℃, and to elucidate the physiological mechanisms by which trees adapt to freezing. The results showed that freezing acclimation enhanced the activities of superoxide dismutase （SOD）, peroxidase （POD）, catalase （CAT）, monodehydroascorbate reductase （MDAR）, ascorbate peroxidase （APX）, dehydroascorbate reductase （DHAR） and glutathione reductase （GR）. And it increased the contents of reduced ascorbate （ASA）, reduced glutathione （GSH）, dehydroascorbate （DHA） and oxidized glutathione （GSSG）. However, H202 and MDA contents and LT50 of cuttings were decreased. LTs0 in cuttings was found to be closely correlated to the levels of SOD, POD, CAT, APX, DHAR, MDAR, GR, H202, MDA, ASA, GSH, DHA and GSSG during freezing acclimation. This suggested that the enhancement of freezing resistance of cuttings induced by freezing acclimation may relate to the distinct increase for the levels of SOD, POD, CAT, APX, DHAR, MDAR, GR, ASA, GSH, DHA, and GSSG. In addition, the observed levels of APX, DHAR, MDAR, GR, ASA, DHA, GSH and GSSG were higher than those of SOD, POD and CAT during freezing acclimation. It indicated that a higher capacity of the ASA-GSH cycle is required for H202 detoxification, and growth and development of cuttings. Based on the obtained results, it can be concluded that the ASA-GSH cycle plays an important role in enhancement of freezing resistance of P. suaveolens cuttings during freezing acclimation.

关键词： Populus suaveolens freezing acclimation antioxidant system ASA-GSH cycle

基于群组分析的组织信任在护士信任患者与工作投入间的中介效应

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护理学报 2024年第5期31卷 1-6页

作者：卢康媛王洁陈玉蓓纪雪梅郑智慧福建中医药大学护理学院福建福州350122 福建医科大学附属三明市第一医院护理部福建三明365000 尤溪县中医医院护理部福建三明365100

目的基于多群组分析,探讨不同级别医院间组织信任在护士信任患者与工作投入之间的中介效应。方法采取便利抽样法,于2022年6月-10月选取福建省三明市共35所三级、二级、一级医院的1 141名临床护士作为研究对象。采用一般资料问卷、工... 详细信息

目的基于多群组分析,探讨不同级别医院间组织信任在护士信任患者与工作投入之间的中介效应。方法采取便利抽样法,于2022年6月-10月选取福建省三明市共35所三级、二级、一级医院的1 141名临床护士作为研究对象。采用一般资料问卷、工作投入量表、护士信任患者量表、组织信任量表进行调查。采用SPSS 26.0分析护士信任患者、组织信任、工作投入的相关性,采用AMOS 26.0构建结构方程模型,分析组织信任在护士信任患者与工作投入间的中介效应,采用多群组分析不同级别医院间模型的差异。结果本研究护士总体的工作投入、护士信任患者、组织信任总分分别为41.00(27.00,48.00)分、48.00(38.00,53.00)分、52.00(52.00,64.00)分。组织信任在护士信任患者与工作投入间存在部分中介作用(β=0.318,P<0.001),中介效应占总效应的56.28%。多群组分析结果显示,二级医院的护士信任患者对组织信任的路径影响(B=0.771,P<0.001)及护士信任患者对工作投入(B=0.289,P<0.001)的路径影响作用最高,三级医院的组织信任对护士工作投入的路径影响作用最高(B=0.454,P<0.001)。结论护士信任患者、组织信任及工作投入总分均处于中等偏上水平,护士对患者的信任可以通过组织信任间接影响工作投入。不同级别医院间护士信任患者、组织信任及工作投入的路径关系存在差异。建议不同级别医院的护理管理者应针对性地制订不同的措施,塑造积极的工作氛围,以提升护理团队的工作投入水平。

关键词：信任护患信任组织信任工作投入

Dual-curvilinear beam enabled tunable manipulation of high-and low-refractive-index particles

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Photonics Research 2024年第7期12卷 1427-1436页

作者： zheng YUAN CHENCHEN ZHANG YUAN GAO WENXIANG YAN XIAN LONG zhi-CHENG REN XI-LIN WANG JIANPING DING hui-TIAN WANG National Laboratory of Solid State Microstructures and School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics Nanjing 210093China

We present an innovative approach for the simultaneous agile manipulation of high-refractive-index(HRI) and low-refractive-index(LRI) particles. Our method involves introducing a dual-curvilinear optical vortex beam(DC-OVB) generated by superimposing a pair of curved beams: HRI and LRI particles are controlled by the bright curve and the dark channel between the two curves, respectively. The proposed DC-OVB provides customizable motion paths and velocities for both LRI and HRI particles. Each curve of the DC-OVB can support a distinct orbital flow density(OFD), enabling the application of torques to HRI and LRI particles, guiding them to orbit along specified trajectories and prompting them to execute various curvilinear motions simultaneously,including curvilinear movement, revolution, and rotation.

关键词： tunable refractive beam

A robust tensor watermarking algorithm for diffusion-tensor images

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 384-397页

作者： Chengmeng LIU zhi LI Guomei WANG Long zheng State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang 550025China

Watermarking algorithms that use convolution neural networks have exhibited good robustness in studies of deep learning ***,after embedding watermark signals by convolution,the feature fusion eficiency of convolution is relatively low;this can easily lead to distortion in the embedded *** distortion occurs in medical images,especially in diffusion tensor images(DTIs),the clinical value of the DTI is *** address this issue,a robust watermarking algorithm for DTIs implemented by fusing convolution with a Transformer is proposed to ensure the robustness of the watermark and the consistency of sampling distance,which enhances the quality of the reconstructed image of the watermarked DTIs after embedding the watermark *** the watermark-embedding network,Ti-weighted(Tlw)images are used as prior *** correlation between T1w images and the original DTI is proposed to calculate the most significant features from the T1w images by using the Transformer *** maximum of the correlation is used as the most significant feature weight to improve the quality of the reconstructed *** the watermark extraction network,the most significant watermark features from the watermarked DTI are adequately learned by the Transformer to robustly extract the watermark signals from the watermark *** results show that the average peak signal-to-noise ratio of the watermarked DTI reaches 50.47 dB,the diffusion characteristics such as mean diffusivity and fractional anisotropy remain unchanged,and the main axis deflection angleαAc is close to *** proposed algorithm can effectively protect the copyright of the DTI and barely affects the clinical diagnosis.

关键词： Robust watermarking algorithm Transformer Image reconstruction Diffusion tensor images Soft attention Hard attention Tl-weighted images

Boundary Points,Minimal L^(2)Integrals and Concavity PropertyⅢ—Linearity on Riemann Surfaces and Fibrations over Open Riemann Surfaces

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2091-2152页

作者： Qi An GUAN zhi Tong MI zheng YUAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044P.R.China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China

In this article,we consider a modified version of minimal L^(2) integrals on sublevel sets of plurisubharmonic functions related to modules at boundary points,and obtain a concavity property of the modified *** applications,we give characterizations for the concavity degenerating to linearity on open Riemann surfaces and on fibrations over open Riemann surfaces.

关键词： Minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex Kähler manifold

Mechanism Design for Ancillary Service Market Considering Social Welfare and Fairness

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1000-1010页

作者： zhi Wu Yuanxi Wu Wei Gu zheng Xu Shu zheng Jingtao Zhao School of Electrical Engineering Southeast UniversityNanjing 210096China NARI Technology Co. Ltd.Nanjing 211106China IEEE CSEE

Increasing penetration of distributed energy resources in the distribution network(DN)is threatening safe operation of the DN,which necessitates setup of the ancillary service market in the *** the ancillary service market,distribution system operator(DSO)is responsible for safety of the DN by procuring available capacities of *** existing studies,this paper proposes a novel market mechanism composed of two parts:choice rule and payment *** proposed choice rule simultaneously considers social welfare and fairness,encouraging risk-averse aggregators to participate in the ancillary service *** is then formulated as a linear programming problem,and a distributed solution using the multi-cut Benders decomposition is ***,successful implementation of the choice rule depends on each aggregator’s truthful adoption of private ***,a payment rule is also designed,which is proved to possess two properties:incentive compatibility and individual *** results demonstrate effectiveness of the proposed choice rule on improving fairness and verify properties of the payment rule.

关键词： Aggregator ancillary service market distributed mechanism fairness mechanism design

Iso-propagation vortices with OAM-independent size and divergence toward future faster optical communications

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Advanced Photonics 2024年第3期6卷 51-59页

作者： Wenxiang Yan Zhaozhong Chen Xian Long Yuan Gao zheng Yuan zhi-Cheng Ren Xi-Lin Wang Jianping Ding hui-Tian Wang Nanjing University School of Physics National Laboratory of Solid State Microstructures Nanjing University Collaborative Innovation Center of Advanced Microstructures University of Glasgow James Watt School of Engineering Nanjing University Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics

Recognized in the 1990s, vortex beams' ability to carry orbital angular momentum(OAM) has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication. However, inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM, limiting vortex beams' applicability in areas such as spatial mode multiplexing communication, fiber-optic data transmission, and particle manipulation. These domains necessitate vortex beams with OAM-independent propagation *** introduce iso-propagation vortices(IPVs), vortex beams characterized by OAM-independent propagation behavior, achieved through precise radial index configuration of Laguerre–Gaussian beams. IPVs display notable transmission dynamics, including a reduced quality factor, resilience post-damage, and decreased and uniform modal scattering under atmospheric turbulence. Their distinctive attributes render IPVs valuable for potential applications in imaging, microscopy, optical communication, metrology, quantum information processing, and light–matter interactions. Notably, within optical communication, the case study suggests that the IPV basis, due to its OAM-independent propagation behavior, provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques, consequently augmenting information capacity.

关键词： orbital angular momentum optical communication structured light optical vortices

Degradation and biocompatibility of one-step electrodeposited magnesium thioctic acid/magnesium hydroxide hybrid coatings on ZE21B alloys for cardiovascular stents

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Journal of Magnesium and Alloys 2024年第1期12卷 120-138页

作者： Zhao-Qi Zhang Bing-zhi Li Pei-Duo Tong Shao-Kang Guan Li Wang zheng-hui Qiu Cun-Guo Lin Rong-Chang Zeng School of Material Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy&Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou University100 Science RoadZhengzhou 450001China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266101China Corrosion Laboratory for Light Metals College of Material Science and EngineeringShandong University of Science and TechnologyQingdao 266590China

Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based ***,the steps for preparing composite coatings are usually complicated and ***,a novel composite coating,composed of bioactive magnesium thioctic acid(MTA)layer formed by deposition and corrosion-resistant magnesium hydroxide(Mg(OH)_(2))layer grown in situ,is simply fabricated on ZE21B alloys via one-step *** electron microscopy(SEM)shows that the electrodeposited coating has a compact and uniform *** the high adhesion of the MTA/Mg(OH)_(2)hybrid coating is also confirmed by the micro-scratch *** test,scanning kelvin probe(SKP),and hydrogen evolution measurement indicate that the hybrid coating effectively reduces the degradation rate of Mg *** experiment and cell culture trial detect that the composite coating is of fine ***,the preparation mechanism of MTA/Mg(OH)_(2)hybrid coatings is discussed and *** coating shows a great potential application for cardiovascular stents.

关键词： Magnesium alloy Corrosion resistance Hybrid coating Endothelialization Biocompatibility

基于局部亮度直方图特征的实时目标识别与跟踪

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系统工程与电子技术 2011年第9期33卷 1927-1931页

作者：孙抗汪渤郑智辉北京理工大学自动化学院北京100081

针对自寻的电视导引头实时跟踪需求及其硬件平台的限制,借鉴离线训练的思想,提出一种基于局部亮度直方图的二进制特征描述算子,利用该算子设计了基于差异度函数和索引值的两级特征匹配方法。算子的二进制特性使得特征匹配过程主要通过... 详细信息

针对自寻的电视导引头实时跟踪需求及其硬件平台的限制,借鉴离线训练的思想,提出一种基于局部亮度直方图的二进制特征描述算子,利用该算子设计了基于差异度函数和索引值的两级特征匹配方法。算子的二进制特性使得特征匹配过程主要通过一系列二进制位运算完成,算法复杂度大大降低。实验表明,该算法实时性强,平均跟踪速度可达25 fps以上,运行过程中内存需求量小,并且对目标尺度变化、旋转、光照变化等具有较好的鲁棒性,满足了导引头实时目标识别与跟踪需求。

关键词：电视导引头特征匹配目标跟踪亮度直方图