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Improvement of a MIMO antenna structure with combination of transmit beamforming and spatial multiplexing

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 91-95页

作者： yuan ting-ting zhang Lei YANG Hong-wen YANG Da-cheng School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Downlinks of the cellular systems generally have more transmit antennas than receive antennas. To efficiently exploit all antenna resources, a technique that combines the advantage of beamforming and spatial multiplexing has been proposed, which partitions the transmit antennas into neighboring sub-groups. In this article, this technique is further improved by Eq. （1） allowing non-contiguous antenna grouping, and Eq. （2） adopting two new grouping criteria： minimum signal distance maximization （MSDM） criterion and maximum correlation coefficient minimization （MCCM） criterion. Simulation results indicate that these improvements can bring noticeable gains in the Rayleigh fiat fading channel environment.

关键词： multiple-input multiple-output (MIMO) beamforming antenna grouping uncorrelated channel semi-correlated channel

Bio-based and Biodegradable Electrospun Fibers Composed of Poly(L-lactide) and Polyamide 4

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Chinese Journal of Polymer Science 2020年第1期38卷 53-62,I0006页

作者： Tao Chen Guo-Cheng Zhong yuan-ting zhang Li-Ming Zhao Yong-Jun Qiu School of Materials Science and Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Bio-based Material Engineering of China National Light Industry Council Shanghai200237China Shanghai Key Laboratory of Advanced Polymeric Materials Shanghai200237China School of Biotechnology East China University of Science and TechnologyShanghai200237China

Novel bio-based and biodegradable block copolymers were synthesized by "click" reaction between poly(L-lactide)(PLLA) and polyamide 4(PA4). Upon tuning the molar mass of PLLA block, the properties of copolymers and electrospun ultrafine fibers were investigated and compared with those of PLLA and PA4 blends. PLLA and PA4 were found incompatible and formed individual crystalline regions, along with reciprocal inhibition in crystallization. Electrospun fibers were highly hydrophobic, even if hydrophilic PA4 was the rich component. The crystallinity of either PLLA or PA4 decreased after electrospinning and PLLA-rich as-spun fibers were almost amorphous. Immersion tests proved that fibers of block copolymers were relatively homogeneous with micro-phase separation between PLLA and PA4. The fibrous structures of copolymers were different from those of the fibers electrospun from blends, for which sheath-core structure induced by macro-phase separation between homopolymers of PLLA and PA4 was confirmed by TEM, EDS, and XPS.

关键词： Poly(L-lactide) Polyamide 4 "Click"reaction Electrospinning Fiber

RECENT DEVELOPMENTS OF TERAHERTZ TECHNOLOGY IN BIOMEDICINE

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Journal of Innovative Optical Health Sciences 2008年第1期1卷 29-44页

作者： EMMA PICKWELL-MACPHERSON SHENGYANG HUANG KANIS WAI CHI KAN YIWEN SUN yuan ting zhang Joint Research Centre for Biomedical Engineering Department of Electronic Engineering The Chinese University of Hong Kong†Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced Technology Chinese Academy of Sciences China Key Laboratory for Biomedical Informatics and Health Engineering Chinese Academy of Science China

Terahertz technology is continually evolving and much progress has been made in recent *** new applications are being discovered and new ways to implement terahertz imaging *** this review,we limit our discussion to biomedical applications of terahertz imaging such as cancer detection,genetic sensing and molecular *** discussion of the development of new terahertz techniques is also focused on those that may accelerate the progress of terahertz imaging and spectroscopy in biomedicine.

关键词： spectroscopy. terahertz limit

pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-yuan Xiang Wen-Long zhang He-ting Li Ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

Clinical nursing value of predictive nursing in reducing complications of pregnant women undergoing short-term massive blood transfusion during cesarean section

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World Journal of Clinical Cases 2024年第1期12卷 51-58页

作者： Li Cheng Li-Ping Li yuan-yuan zhang Fang Deng ting-ting Lan Department of Obstertrics Wuhan Third HospitalWuhan 430000Hubei ProvinceChina Department of Gynaecology Wuhan No.1 HospitalWuHan 430030Hubei ProvinceChina Center for Reproductive Medicine Department of Obstetrics and GynecologySichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress ***,predictive nursing intervention has important clinical significance for *** To explore the effect of predictive nursing intervention on the stress response and complications of women undergoing short-term mass blood transfusion during cesarean section(CS).METHODS A clinical medical record of 100 pregnant women undergoing rapid mass blood transfusion during sections from June 2019 to June *** to the different nursing methods,patients divided into control group(n=50)and observation group(n=50).Among them,the control group implemented routine nursing,and the observation group implemented predictive nursing intervention based on the control ***,compared the differences in stress res-ponse,complications,and pain scores before and after the nursing of pregnant women undergoing rapid mass blood transfusion during *** The anxiety and depression scores of pregnant women in the two groups were significantly improved after nursing,and the psychological stress response of the observation group was significantly lower than that of the control group(P<0.05).The heart rate and mean arterial pressure(MAP)of the observation group during delivery were lower than those of the control group,and the MAP at the end of delivery was lower than that of the control group(P<0.05).Moreover,different pain scores improved significantly in both groups,with the observation group considerably less than the control group(P<0.05).After nursing,complications such as skin rash,urinary retention,chills,diarrhea,and anaphylactic shock in the observation group were 18%,which significantly higher than in the control group(4%)(P<0.05).CONCLUSION Predictive nursing intervention can effectively relieve the pain,reduce the incidence of complications,improve mood and stress response,and serve as a

关键词： Predictive care Rapid mass blood transfusion Cesarean section Stress response Complications

Timing theory integrated nursing combined behavior change integrated theory of nursing on primiparous influence

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World Journal of Clinical Cases 2024年第2期12卷 293-301页

作者： Yan-Xia He Yang Lv ting-ting Lan Fang Deng yuan-yuan zhang Department of Obstetrics and Gynecology Wuhan Children’s HospitalWuhan 430015Hubei ProvinceChina Center for Reproductive Medicine Department of Obstetrics and GynecologySichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for *** has the potential to enhance the psychological well-being and overall quality of life for primipara,while also furnishing healthcare providers with efficacious interventions to tackle the psychological and physiological obstacles encountered during the stages of pregnancy and *** To explore the effect of timing theory combined with behavior change on selfefficacy,negative emotions and quality of life in patients with *** A total of 80 primipara cases were selected and admitted to our hospital between August 2020 and May *** cases were divided into two groups,namely the observation group and the control group,with 40 cases in each *** nursing interventions differed between the two groups,with the control group receiving routine nursing and the observation group receiving integrated nursing based on the timing theory and behavior *** study aimed to compare the pre-and post-nursing scores of Chinese Perceived Stress Scale(CPSS),Edinburgh Postpartum Depression Scale(EPDS),Self-rating Anxiety Scale(SAS),breast milk knowledge,self-efficacy,and SF-36 quality of life in both *** After nursing,the CPSS,EPDS,and SAS scores of the two groups was significantly lower than that before nursing,and the CPSS,EPDS,and SAS scores of the observation group was significantly lower than that of the control group(P=0.002,P=0.011,and P=0.001 respectively).After nursing,the breastfeeding knowledge mastery,selfefficacy,and SF-36 quality of life scores was significantly higher than that before nursing,and the breastfeeding knowledge mastery(P=0.013),self-efficacy(P=0.008),and SF-36 quality of life(P=0.011)scores of the observation group was significantly higher than that of the control *** The integration of timing theory and behavior

关键词： Timing theory Behavior change Primipara Bad mood Quality of life

Research Progress in the Fabrication of Covalent Organic Framework Membranes for Chemical Separations

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Chinese Journal of Polymer Science 2024年第2期42卷 141-158,I0005页

作者： Cui-ting Ding Jin-Qiu yuan Meng-Ying Xie Qing-yuan Liu Zeng-Guang Yao Shi-Yu zhang Run-Nan zhang Hong Wu Zhong-Yi Jiang Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Zhejiang Institute of Tianjin University NingboZhejiang315201China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Tianjin Key Laboratory of Membrane Science and Desalination Technology Tianjin UniversityTianjin300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.

关键词： Covalent organic frameworks Covalent organic framework membranes Water treatment Organic solvent nanofiltration Gas separation

Snap-through behaviors and nonlinear vibrations of a bistable composite laminated cantilever shell:an experimental and numerical study

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 779-794页

作者： Lele REN Wei zhang ting DONG Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

The snap-through behaviors and nonlinear vibrations are investigated for a bistable composite laminated cantilever shell subjected to transversal foundation excitation based on experimental and theoretical *** improved experimental specimen is designed in order to satisfy the cantilever support boundary condition,which is composed of an asymmetric region and a symmetric *** symmetric region of the experimental specimen is entirely clamped,which is rigidly connected to an electromagnetic shaker,while the asymmetric region remains free of *** motion paths are realized for the bistable cantilever shell by changing the input signal levels of the electromagnetic shaker,and the displacement responses of the shell are collected by the laser displacement *** numerical simulation is conducted based on the established theoretical model of the bistable composite laminated cantilever shell,and an off-axis three-dimensional dynamic snap-through domain is *** numerical solutions are in good agreement with the experimental *** nonlinear stiffness characteristics,dynamic snap-through domain,and chaos and bifurcation behaviors of the shell are quantitatively *** to the asymmetry of the boundary condition and the shell,the upper stable-state of the shell exhibits an obvious soft spring stiffness characteristic,and the lower stable-state shows a linear stiffness characteristic of the shell.

关键词： bistable composite laminated cantilever shell snap-through behavior nonlinear vibration nonlinear stiffness characteristic chaos and bifurcation

Histological Features of Uterine Myometrial Dysfunction:Possible Involvement of Localized Inflammation

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Current Medical Science 2024年第3期44卷 633-641页

作者： Sheng-lan ZHU Hui-ting zhang yuan-yuan DU Yi JIANG Shao-shuai WANG Wen-cheng DING Ling FENG National Clinical Research Center for Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective The latest perspective suggests that elevated levels of inflammation and cytokines are implicated in atonic postpartum ***(LPS)has been widely used to induce inflammation in animal ***,this study aimed to induce uterine inflammation using LPS to investigate whether local inflammation triggers dysfunction and atrophy in the myometrium,as well as the potential underlying molecular mechanisms *** In vivo,an animal model was established by intraperitoneal injection of 300μg/kg LPS in rats on gestational day ***-eosin(H&E)staining and Masson staining were employed to determine morphological changes in the rat uterine smooth ***-linked immunosorbent assay(ELISA)was used to detect inflammatory ***,tissue fluorescence,and Western blotting were conducted to assess the expression levels of the uterine contraction-related proteins Toll-like receptor 4(TLR4)and the nuclear factor kappa-B(NF-κB)signaling *** vitro,human uterine smooth muscle cells(HUtSMCs)were exposed to 2μg/mL LPS to further elucidate the involvement of the TLR4/NF-κB signaling pathway in LPS-mediated *** In this study,LPS induced uterine myometrial dysfunction in rats,leading to a disorganized arrangement,a significant increase in collagen fiber deposition,and widespread infiltration of inflammatory *** both in vivo animal models and in vitro HUtSMCs,LPS elevated IL-6,IL-1β,and TNF-αlevels while concurrently suppressing the expression of connexin 43(Cx43)and oxytocin receptor(OXTR).Mechanistically,the LPS-treated group exhibited TLR4 activation,and the phosphorylation levels of p65 and IκBαwere notably *** LPS triggered the TLR4/NF-κB signaling pathway,inducing an inflammatory response in the myometrium and leading to uterine myometrial dysfunction and uterine atony.

关键词： lipopolysaccharide inflammatory response TLR4 NF-κB myometrium