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In vivo imaging of the neuronal response to spinal cord injury:a narrative review
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作者 Junhao Deng Chang Sun +5 位作者 ying zheng Jianpeng Gao Xiang Cui Yu Wang Licheng Zhang Peifu Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期811-817,共7页
Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are ... Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are lacking.Emerging in vivo imaging and labeling methods offer great potential for observing dynamic neural processes in the central nervous system in conditions of health and disease.This review first discusses in vivo imaging of the mouse spinal cord with a focus on the latest imaging techniques,and then analyzes the dynamic biological response of spinal cord sensory and motor neurons to SCI.We then summarize and compare the techniques behind these studies and clarify the advantages of in vivo imaging compared with traditional neuroscience examinations.Finally,we identify the challenges and possible solutions for spinal cord neuron imaging. 展开更多
关键词 anterior horn neurons calcium imaging central nervous system dorsal horn neurons dorsal root ganglion in vivo imaging neuronal response spinal cord injury spinal cord two-photon microscopy
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Sustainable ammonia synthesis:An in-depth review of non-thermal plasma technologies
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作者 Vahid Shahed Gharahshiran ying zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期1-38,共38页
Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free combustion.Additionally,it offers convenient transport... Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free combustion.Additionally,it offers convenient transportation and storage as a hydrogen carrier.The dominant method used for large-scale ammonia production is the Haber-Bosch process,which requires high temperatures and pressures and is energy-intensive.However,non-thermal plasma offers an eco-friendly alternative for ammonia synthesis,gaining significant attention.It enables ammonia production at lower temperatures and pressures using plasma technology.This review provides insights into the catalyst and reactor developments,which are pivotal for promoting ammonia efficiency and addressing existing challenges.At first,the reaction kinetics and mechanisms are introduced to gain a comprehensive understanding of the reaction pathways involved in plasma-assisted ammonia synthesis.Thereafter,the enhancement of ammonia synthesis efficiency is discussed by developing and optimizing plasma reactors and effective catalysts.The effect of other feeding sources,such as water and methane,instead of hydrogen is also presented.Finally,the challenges and possible solutions are outlined to facilitate energy-saving and enhance ammonia efficiency in the future. 展开更多
关键词 Nitrogen fixation Ammonia synthesis NH_(3) Non-thermal plasma NI Ru catalyst
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Development of Fixture Layout Optimization for Thin-Walled Parts:A Review
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作者 Changhui Liu Jing Wang +3 位作者 Binghai Zhou Jianbo Yu ying zheng Jianfeng Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期15-39,共25页
An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past decades.However,few papers systematically review these researches.By analyzing existing lit... An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past decades.However,few papers systematically review these researches.By analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods applied.The process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout optimization.This paper makes a review of the fixture layout for thin-walled parts according to these three steps.First,two different kinds of optimization objectives are introduced.Researchers usually consider in-plane variations or out-of-plane deformations when designing objectives.Then,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based methods.Several common methods are discussed respectively.After that,optimization algorithms are reviewed systematically.There are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic algorithms.Finally,discussions on the current situation are provided.The research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization algorithms.Also,a new research point for fixture layout optimization is discussed.This paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field. 展开更多
关键词 Thin-walled parts Assembly quality Fixture layout optimization Modeling methods Optimization algorithms
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Optimization of Fixture Number in Large Thin-Walled Parts Assembly Based on IPSO
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作者 Changhui Liu Jing Wang +3 位作者 ying zheng Ke Jin Jianbo Yu Jianfeng Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期213-227,共15页
There are lots of researches on fixture layout optimization for large thin-walled parts.Current researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of fixtures.However,how to... There are lots of researches on fixture layout optimization for large thin-walled parts.Current researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of fixtures.However,how to determine the number of fixtures is ignored.In most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra waste.Therefore,this paper constructs an optimization model to minimize the number of fixtures.The constraints are set in the optimization model to ensure that the part deformation is within the surface profile tolerance.In addition,the assembly gap between two parts is also controlled.To conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia weight.In the algorithm,particles are encoded according to the fixture position.Each dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization efficiency.Finally,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality requirements.This research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time. 展开更多
关键词 Assembly quality Large thin-walled parts Fixture layout PSO FEM
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Icariin Ameliorates D-galactose-induced Cell Injury in Neuron-like PC12 Cells by Inhibiting MPTP Opening
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作者 Shan-shan HU Tong-yao WANG +8 位作者 Lu NI Fan-xin HU Bo-wen YUE ying zheng Tian-lun WANG Abhishek KUMAR Yan-yan WANG Jin-e WANG Zhi-yong ZHOU 《Current Medical Science》 SCIE CAS 2024年第4期748-758,共11页
Objective Icariin(ICA)has a good neuroprotective effect and can upregulate neuronal basal autophagy in naturally aging rats.Mitochondrial dysfunction is associated with brain aging-related neurodegenerative diseases.A... Objective Icariin(ICA)has a good neuroprotective effect and can upregulate neuronal basal autophagy in naturally aging rats.Mitochondrial dysfunction is associated with brain aging-related neurodegenerative diseases.Abnormal opening of the mitochondrial permeability transition pore(mPTP)is a crucial factor in mitochondrial dysfunction and is associated with excessive autophagy.This study aimed to explore that ICA protects against neuronal injury by blocking the mPTP opening and down-regulating autophagy levels in a D-galactose(D-gal)-induced cell injury model.Methods A cell model of neuronal injury was established in rat pheochromocytoma cells(PC12 cells)treated with 200 mmol/L D-gal for 48 h.In this cell model,PC12 cells were pre-treated with different concentrations of ICA for 24 h.MTT was used to detect cell viability.Senescence associatedβ-galactosidase(SA-β-Gal)staining was used to observe cell senescence.Western blot analysis was performed to detect the expression levels of a senescence-related protein(p21),autophagy markers(LC3B,p62,Atg7,Atg5 and Beclin 1),mitochondrial fission and fusion-related proteins(Drp1,Mfn2 and Opa1),and mitophagy markers(Pink1 and Parkin).The changes of autophagic flow were detected by using mRFP-GFP-LC3 adenovirus.The intracellular ultrastructure was observed by transmission electron microscopy.Immunofluorescence was used to detect mPTP,mitochondrial membrane potential(MMP),mitochondrial reactive oxygen species(mtROS)and ROS levels.ROS and apoptosis levels were detected by flow cytometry.Results D-gal treatment significantly decreased the viability of PC12 cells,and markedly increased the SA-β-Gal positive cells as compared to the control group.With the D-gal stimulation,the expression of p21 was significantly up-regulated.Furthermore,D-gal stimulation resulted in an elevated LC3B II/I ratio and decreased p62 expression.Meanwhile,autophagosomes and autolysosomes were significantly increased,indicating abnormal activation of autophagy levels.In addition,in this D-gal-induced model of cell injury,the mPTP was abnormally open,the ROS generation was continuously increased,the MMP was gradually decreased,and the apoptosis was increased.ICA effectively improved mitochondrial dysfunction to protect against D-gal-induced cell injury and apoptosis.It strongly inhibited excessive autophagy by blocking the opening of the mPTP.Cotreatment with ICA and an mPTP inhibitor(cyclosporin A)did not ameliorate mitochondrial dysfunction.However,the protective effects were attenuated by cotreatment with ICA and an mPTP activator(lonidamine).Conclusion ICA inhibits the activation of excessive autophagy and thus improves mitochondrial dysfunction by blocking the mPTP opening. 展开更多
关键词 ICARIIN neuronal injury mitochondrial dysfunction mitochondrial permeability transition pore AUTOPHAGY
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Advanced nanomedicines and immunotherapeutics to treat respiratory diseases especially COVID-19 induced thrombosis
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作者 Jie Wu ying zheng +3 位作者 Li-Na Zhang Cai-Li Gu Wang-Li Chen Min-Qiang Chang 《World Journal of Clinical Cases》 SCIE 2024年第16期2704-2712,共9页
Immunotherapy and associated immune regulation strategies gained huge attraction in order to be utilized for treatment and prevention of respiratory diseases.Engineering specifically nanomedicines can be used to regul... Immunotherapy and associated immune regulation strategies gained huge attraction in order to be utilized for treatment and prevention of respiratory diseases.Engineering specifically nanomedicines can be used to regulate host immunity in lungs in the case of respiratory diseases including coronavirus disease 2019(COVID-19)infection.COVID-19 causes pulmonary embolisms,thus new therapeutic options are required to target thrombosis,as conventional treatment options are either not effective due to the complexity of the immunethrombosis pathophysiology.In this review,we discuss regulation of immune response in respiratory diseases especially COVID-19.We further discuss thrombosis and provide an overview of some antithrombotic nanoparticles,which can be used to develop nanomedicine against thrombo-inflammation induced by COVID-19 and other respiratory infectious diseases.We also elaborate the importance of immunomodulatory nanomedicines that can block pro-inflammatory signalling pathways,and thus can be recommended to treat respiratory infectious diseases. 展开更多
关键词 NANOMEDICINES IMMUNOTHERAPEUTICS Respiratory diseases COVID-19 THROMBOSIS
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安徽省2种外来植物分布新记录
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作者 邹晓东 应征 张思宇 《安徽林业科技》 2024年第3期62-64,共3页
本文介绍了近年发现于安徽蚌埠的2种外来植物分布新记录——芒苞车前(Plantago aristata)、睫毛坚扣草(Hexasepalum teres),并提供了详细的形态描述和照片、采集地点及分布状况等信息。这2种外来植物在安徽的新分布记录显示,外来植物入... 本文介绍了近年发现于安徽蚌埠的2种外来植物分布新记录——芒苞车前(Plantago aristata)、睫毛坚扣草(Hexasepalum teres),并提供了详细的形态描述和照片、采集地点及分布状况等信息。这2种外来植物在安徽的新分布记录显示,外来植物入侵范围进一步扩大。 展开更多
关键词 新记录 分布 外来植物
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Enhanced selective hydrogenation of glycolaldehyde to ethylene glycol over Cu^(0)-Cu^(+)sites 被引量:1
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作者 Qi Yang Weikang Dai +8 位作者 Maoshuai Li Jie Wei Yi Feng Cheng Yang Wanxin Yang ying zheng Jie Ding Mei-Yan Wang Xinbin Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期141-150,共10页
Selective hydrogenation of hydroxyaldehydes to polyalcohols is challenging due to the competitive hydrogenation of C=O and CAO.This study develops heterogeneous Cu catalysts for the selective synthesis of ethylene gly... Selective hydrogenation of hydroxyaldehydes to polyalcohols is challenging due to the competitive hydrogenation of C=O and CAO.This study develops heterogeneous Cu catalysts for the selective synthesis of ethylene glycol via batch liquid-phase hydrogenation of glycolaldehyde.SiO_(2)supported Cu,fabricated by ammonia evaporation,enables to catalyze the C=O bond hydrogenation with retaining the CAO bond intact,yielding higher selective hydrogenation activity with ethylene glycol selectivity up to 99.8%relative to MgO,Al_(2)O_(3),CeO_(2),and TiO_(2)supports and Cu/SiO_(2)synthesized by deposition–precipitation and impregnation.Characterizations confirm that highly efficient 20Cu/SiO_(2)-AE-623 K catalyst fabricated by ammonia evaporation is featured with larger Cu^(0)and Cu^(+)surface areas,of which the Cu^(+)species created from reducing copper phyllosilicate exhibit higher reactivity.A synergistic effect between Cu^(+)and Cu^(0)facilitates the selective adsorption/activation of glycolaldehyde on Cu^(+)sites and the dissociation of H_(2)on Cu^(0)sites,bringing a remarkable improvement in the selective hydrogenation performance. 展开更多
关键词 HYDROGENATION Multiphase reaction Biomass Copper phyllosilicate Ammonia evaporation
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Joint Detection of Serum Vitamin D,Body Mass Index,and Tumor Necrosis Factor Alpha for the Diagnosis of Crohn’s Disease 被引量:1
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作者 ying zheng Jing-hong LI +7 位作者 Shan-ying LIAO Yi-ming FU Yan-jun ZHANG Jun-long LIN Xin-bin CHEN Wei-hong SHA Shi-xue DAI Wen-jun MA 《Current Medical Science》 SCIE CAS 2023年第3期496-504,共9页
Objective Vitamin D(VD)deficiency was reported to contribute to the progression of Crohn’s disease(CD)and affect the prognosis of CD patients.This study investigated the role of serum VD,body mass index(BMI),and tumo... Objective Vitamin D(VD)deficiency was reported to contribute to the progression of Crohn’s disease(CD)and affect the prognosis of CD patients.This study investigated the role of serum VD,body mass index(BMI),and tumor necrosis factor alpha(TNF-α)in the diagnosis of Crohn’s disease.Methods CD patients(n=76)and healthy subjects(n=76)were enrolled between May 2019 and December 2020.The serum 25-hydroxyvitamin D[25(OH)D]levels,BMI,and TNF-αlevels,together with other biochemical parameters,were assessed before treatment.The diagnostic efficacy of the single and joint detection of serum 25(OH)D,BMI,and TNF-αwas determined using receiver operating characteristic(ROC)curves.Results The levels of 25(OH)D,BMI,and nutritional indicators,including hemoglobin,total protein,albumin,and high-density lipoprotein cholesterol,were much lower,and the TNF-αlevels were much higher in the CD patients than in the healthy subjects(P<0.05 for all).The areas under the ROC curve for the single detection of 25(OH)D,BMI,and TNF-αwere 0.887,0.896,and 0.838,respectively,with the optimal cutoff values being 20.64 ng/mL,19.77 kg/m^(2),and 6.85 fmol/mL,respectively.The diagnostic efficacy of the joint detection of 25(OH)D,BMI,and TNF-αwas the highest,with an area under the ROC curve of 0.988(95%CI:0.968–1.000).Conclusion The joint detection of 25(OH)D,TNF-α,and BMI showed high sensitivity,specificity,and accuracy in CD diagnosis;thus,it would be effective for the diagnosis of CD in clinical practice. 展开更多
关键词 Crohn’s disease vitamin D body mass index tumor necrosis factor alpha
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基于神经网络的焊缝跟踪系统视觉标定方法 被引量:1
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作者 王嘉盛 张斌 +1 位作者 应征 林子祥 《现代电子技术》 2023年第11期55-59,共5页
文中提出一种基于深度神经网络的焊缝跟踪系统机器人视觉标定方法,实现了机器人的简单快速标定。将焊缝跟踪传感器安装在机械臂末端,使用线激光器对被检测角点进行定位,工业相机拍摄对应的标定棋盘图像,用角点提取算法获取到相应棋盘格... 文中提出一种基于深度神经网络的焊缝跟踪系统机器人视觉标定方法,实现了机器人的简单快速标定。将焊缝跟踪传感器安装在机械臂末端,使用线激光器对被检测角点进行定位,工业相机拍摄对应的标定棋盘图像,用角点提取算法获取到相应棋盘格点的数字图像坐标,并通过示教器读取机械臂的各个关节角,利用神经网络极强的非线性映射能力,将其传入训练好的BP神经网络进行三维空间坐标的预测。此方法能够实现机器人的快速标定,避开传统标定方法中复杂的非线性运算,并减少坐标转换间的累积误差。实验结果表明,基于神经网络的标定方法具有较高的精度,且标定过程简单,为机器人视觉标定提供了一种新的方法。 展开更多
关键词 视觉标定 焊缝跟踪系统 神经网络 机器人标定 像素点提取 空间坐标预测
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Non-symmetric distributions of solids deposition for solid-water stratified flow in deviated tubing strings
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作者 Xin-Fu Liu Chun-Hua Liu +7 位作者 Zhong-Xian Hao ying zheng Kai Zhang Jian-Feng Wang Song-Bo Wei Ai-Gang Hao Jun-Ling Tao Hui Cheng 《Petroleum Science》 SCIE EI CSCD 2023年第5期3048-3061,共14页
Dynamic performance on solids flow with water in deviated tubing is essential for the reliability of pump and normal operation of horizontal and directional wells.Compared with coal-water flow in vertical tubing and s... Dynamic performance on solids flow with water in deviated tubing is essential for the reliability of pump and normal operation of horizontal and directional wells.Compared with coal-water flow in vertical tubing and sand-oil flow with high production in deviated tubing,solids deposition with water shows obvious non-symmetric distributions in deviated tubing from simulations and experiments.The mathematical model of two phase flow was developed under coupling conditions of deviated tubing,low flow rate and viscosity based on the kinetic theory of granular flow and first-order discrete scheme.The results show that solid-water stratified flow in deviated tubing can be divided into two zones of suspension bed and the moving bed throughout the flow field.The solid flowing velocity with water is negative and particles slide down at the bottom of moving bed zone.The process of solids flow with water in deviated tubing will produce pressure loss and consume the kinetic energy.The thickness of deposited layer and the flowing velocity of solids flow downward with water at the moving bed zone enhance with the decreased inlet flow rate and the increased particle size,tubing inside diameter(ID)and inclination angle.Solids are easier into suspension from the upper part of moving bed zone to suspension bed zone and more solid particles flow with water towards the tubing outlet with the increase of inlet flowing velocity.The decision is made to reduce the screen width,tubing ID and inclination angle to maintain to be greater than critical deposition velocity in order to prevent solids settling.And it provides the theoretical basis and technical reserves for solid control and offers an effective approach to enhance tubing cleaning in deviated strings. 展开更多
关键词 Deviated tubing Stratified flow Solid deposition Critical velocity Prevent solids settling
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Predicting liposome formulations by the integrated machine learning and molecular modeling approaches
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作者 Run Han Zhuyifan Ye +3 位作者 Yunsen Zhang Yaxin Cheng ying zheng Defang Ouyang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第3期104-117,共14页
Liposome is one of the most widely used carriers for drug delivery because of the great biocompatibility and biodegradability.Due to the complex formulation components and preparation process,formulation screening mos... Liposome is one of the most widely used carriers for drug delivery because of the great biocompatibility and biodegradability.Due to the complex formulation components and preparation process,formulation screening mostly relies on trial-and-error process with low efficiency.Here liposome formulation prediction models have been built by machine learning(ML)approaches.The important parameters of liposomes,including size,polydispersity index(PDI),zeta potential and encapsulation,are predicted individually by optimal ML algorithm,while the formulation features are also ranked to provide important guidance for formulation design.The analysis of key parameter reveals that drug molecules with logS[-3,-6],molecular complexity[500,1000]and XLogP3(≥2)are priority for preparing liposome with higher encapsulation.In addition,naproxen(NAP)and palmatine HCl(PAL)represented the insoluble and water-soluble molecules are prepared as liposome formulations to validate prediction ability.The consistency between predicted and experimental value verifies the satisfied accuracy of ML models.As the drug properties are critical for liposome particles,the molecular interactions and dynamics of NAP and PAL liposome are further investigated by coarse-grained molecular dynamics simulations.The modeling structure reveals that NAP molecules could distribute into lipid layer,while most PAL molecules aggregate in the inner aqueous phase of liposome.The completely different physical state of NAP and PAL confirms the importance of drug properties for liposome formulations.In summary,the general prediction models are built to predict liposome formulations,and the impacts of key factors are analyzed by combing ML with molecular modeling.The availability and rationality of these intelligent prediction systems have been proved in this study,which could be applied for liposome formulation development in the future. 展开更多
关键词 LIPOSOME Formulation prediction Machine learning Molecular modeling
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Effects of different intervention methods on psychological flexibility,negative emotions and sleep quality in chronic hepatitis B
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作者 ying zheng Xiao-Wei Wang Chen-Xi Xia 《World Journal of Psychiatry》 SCIE 2023年第10期753-762,共10页
BACKGROUND Patients with chronic hepatitis B(CHB)experience various problems,including low psychological flexibility,negative emotions,and poor sleep quality.Therefore,effective nursing interventions are required to r... BACKGROUND Patients with chronic hepatitis B(CHB)experience various problems,including low psychological flexibility,negative emotions,and poor sleep quality.Therefore,effective nursing interventions are required to reduce adverse events.Acceptance and commitment therapy(ACT)combined with enabling cognitivebehavioral education(ECBE)can improve patients'psychological and sleep.Therefore,we speculate that this may also be effective in patients with CHB.AIM To investigate the effects of different intervention methods on psychological flexibility,negative emotions,and sleep quality in patients with CHB.METHODS This retrospective study examined clinical and evaluation data of 129 patients with CHB.Intervention methods were divided into a conventional group(routine nursing,n=69)and a combination group(ACT combined with ECBE,n=60).We observed changes in psychological flexibility,negative emotions,sleep quality,and self-care ability in both groups.Observation items were evaluated using the Acceptance and Action Questionnaire-2nd Edition(AAQ-II),Self-Rating Anxiety Scale(SAS),Self-Rating Depression Scale(SDS),Pittsburgh Sleep Quality Index(PSQI),and Exercise of Self-Care Agency Scale(ESCA).RESULTS Compared with the conventional group,the AAQ-II score of the combined group was lower(F_(between-group effect)=8.548;F_(time effects)=25.020;F_(interaction effects)=52.930;all P<0.001),the SAS score(t=5.445)and SDS score(t=7.076)were lower(all P<0.001),as were the PSQI dimensions(tsleep quality=4.581,tfall sleep time=2.826,tsleep time=2.436,tsleep efficiency=5.787,tsleep disorder=5.008,thypnotic drugs=3.786,tdaytime dysfunction=4.812);all P<0.05).The ESCA scores for all dimensions were higher(thealth knowledge level=6.994,t self-concept=5.902,tself-responsibility=19.820,tself-care skills=8.470;all P<0.001).CONCLUSION ACT combined with ECBE in patients with CHB can improve psychological flexibility and sleep quality,alleviate negative emotions,and improve self-care. 展开更多
关键词 Acceptance and commitment therapy Empowerment cognitive-behavioral education Chronic hepatitis B Psychological flexibility Negative emotion Sleep quality
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聚酰亚胺/TiO_2有机-无机纳米复合膜材料的合成与表征 被引量:19
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作者 杜宏伟 孔瑛 +1 位作者 ying zheng 史德青 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2004年第1期83-86,共4页
以钛酸丁酯作前驱物,NMP为共溶剂,在可溶性聚酰亚胺PI(HQDPA-DMMDA)中通过溶胶-凝胶法制备出高TiO2含量的PI/TiO2有机-无机纳米复合膜材料。TiO2的实际含量高达35.5%时仍能成膜,低于27.2%时为透明浅黄色纳米复合膜。并通过XPS、WAXD、TG... 以钛酸丁酯作前驱物,NMP为共溶剂,在可溶性聚酰亚胺PI(HQDPA-DMMDA)中通过溶胶-凝胶法制备出高TiO2含量的PI/TiO2有机-无机纳米复合膜材料。TiO2的实际含量高达35.5%时仍能成膜,低于27.2%时为透明浅黄色纳米复合膜。并通过XPS、WAXD、TG、DSC等手段对复合材料的结构和性能进行了表征。结果表明,在TiO2含量为27.2%时,PI/TiO2复合材料中TiO2的平均颗粒尺寸为35nm左右;热分解温度和玻璃化转变温度明显升高;复合材料力学性能良好。 展开更多
关键词 聚酰亚胺 二氧化钛 有机-无机纳米复合膜 结构 力学性能
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专利信号如何缓解企业融资约束——基于专利质押融资政策的效果评价 被引量:12
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作者 郑莹 张庆垒 《管理学季刊》 2019年第1期55-72,100,共19页
信号理论相关研究认为专利可以作为一种质量信号,帮助企业获得投资者的认可,缓解企业融资约束。本文基于信号环境和信号有效性的理论关系,探索了中国情境下政府政策演变对专利融资作用的影响,评估了近十年来各地推行的专利质押政策的政... 信号理论相关研究认为专利可以作为一种质量信号,帮助企业获得投资者的认可,缓解企业融资约束。本文基于信号环境和信号有效性的理论关系,探索了中国情境下政府政策演变对专利融资作用的影响,评估了近十年来各地推行的专利质押政策的政策效果。基于2000~2015年11621个企业-年度观测值的面板数据与广义双差分(DID)政策评价模型分析结果显示,专利缓解了中国企业的融资约束,但仅限于发明专利;同时,地方政府推行专利质押政策总体上并没有加强专利的融资作用。事后分析进一步指出,专利质押政策效果在技术交易发达地区却是显著的。该结果意味着政策效果的发挥还依赖于市场完善度,投资者对信号的认可度受到制度和市场环境的共同影响。 展开更多
关键词 信号理论 融资约束 专利质押 政策评价
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城市垃圾管理模式比较研究——以香港和新加坡为例 被引量:1
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作者 英震 《时代经贸》 2019年第30期44-45,共2页
面对日益严重的城市垃圾问题,香港、新加坡根据地方自身实际,设计采用了一套行之有效的垃圾管理模式,值得比较分析、学习借鉴。城市在让人们生活更美好的同时,迅速增长的垃圾也已成为威胁城市发展的重要议题。香港、新加坡通过采取有效... 面对日益严重的城市垃圾问题,香港、新加坡根据地方自身实际,设计采用了一套行之有效的垃圾管理模式,值得比较分析、学习借鉴。城市在让人们生活更美好的同时,迅速增长的垃圾也已成为威胁城市发展的重要议题。香港、新加坡通过采取有效措施,较好应对了“垃圾围城”这一难题。 展开更多
关键词 香港 新加坡 家居废物源头分类计划 自愿包装协议
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Value of bevacizumab in treatment of colorectal cancer: A meta-analysis 被引量:17
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作者 Chun-ying Qu ying zheng +4 位作者 Min Zhou Yi Zhang Feng Shen Jia Cao Lei-Ming Xu 《World Journal of Gastroenterology》 SCIE CAS 2015年第16期5072-5080,共9页
AIM:To assess the efficacy and safety of bevacizumab in the treatment of colorectal cancer.METHODS:All randomized controlled trials of bevacizumab for the treatment of colorectal cancer from January 2003 to June 2013 ... AIM:To assess the efficacy and safety of bevacizumab in the treatment of colorectal cancer.METHODS:All randomized controlled trials of bevacizumab for the treatment of colorectal cancer from January 2003 to June 2013 were collected by searching the Cochrane Library, Pub Med, Chinese National Knowledge Infrastructure and Wanfang databases.The primary endpoint was overall survival(OS), and the secondary endpoints were progression-free survival, overall response rate and adverse events.Two reviewers extracted data independently.Statistical analyses were performed with Stata 12.0.The degree of bias was assessed using funnel plots for the effect size of OS at the primary endpoint.RESULTS:Following the inclusion criteria and exclusion criteria, ten studies comprising 6977 cases were finally included, of which nine were considered to be of high quality(4-7 points) and one of low quality(1-3 points).Our meta-analysis revealed the efficacy of bevacizumab in patients with colorectal cancer in terms of OS(HR = 0.848, 95%CI:0.747-0.963), progressionfree survival(HR = 0.617, 95%CI:0.530-0.719), and overall response rate(OR = 1.627, 95%CI:1.199-2.207).Regarding safety, higher rates of grade ≥ 3 hypertension, proteinuria, bleeding, thrombosis, and gastrointestinal perforation were observed in the bevacizumab treatment group(P < 0.05); however, the incidence of serious toxicity was very low.There was no publication bias in the 10 reports included in this meta-analysis.CONCLUSION:The clinical application of bevacizumab in colorectal cancer is effective with good safety. 展开更多
关键词 BEVACIZUMAB COLORECTAL cancer Clinicalapplication RANDOMIZED controlled trials META-ANALYSIS
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Breast cancer screening and early diagnosis in Chinese women 被引量:17
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作者 Rui Ding Yi Xiao +3 位作者 Miao Mo ying zheng Yi-Zhou Jiang Zhi-Ming Shao 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第4期450-467,共18页
Breast cancer is the most common malignant tumor in Chinese women,and its incidence is increasing.Regular screening is an effective method for early tumor detection and improving patient prognosis.In this review,we an... Breast cancer is the most common malignant tumor in Chinese women,and its incidence is increasing.Regular screening is an effective method for early tumor detection and improving patient prognosis.In this review,we analyze the epidemiological changes and risk factors associated with breast cancer in China and describe the establishment of a screening strategy suitable for Chinese women.Chinese patients with breast cancer tend to be younger than Western patients and to have denser breasts.Therefore,the age of initial screening in Chinese women should be earlier,and the importance of screening with a combination of ultrasound and mammography is stressed.Moreover,Chinese patients with breast cancers have several ancestry-specific genetic features,and aiding in the determination of genetic screening strategies for identifying high-risk populations.On the basis of current studies,we summarize the development of risk-stratified breast cancer screening guidelines for Chinese women and describe the significant improvement in the prognosis of patients with breast cancer in China. 展开更多
关键词 Breast cancer SCREENING CHINESE imaging screening genetic test
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Enhancement of vitamin A combined vitamin D supplementation on immune response to Bacille Calmette-Guerin vaccine revaccinated in Chinese infants 被引量:5
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作者 ying zheng Xue-Gang Li +6 位作者 Qiu-Zhen Wang Ai-Guo Ma Ib Christian Bygbjerg Yong-Ye Sun Yong Li Ming-Ci zheng Xi Wang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第2期130-135,共6页
Objective:To investigate whether there is an association between diameter of bacille CalmetteGuerin(BCG)sears and effect of purified protein derivative(PPD)reaction anil to determine whether vitamin A(VA)combined vita... Objective:To investigate whether there is an association between diameter of bacille CalmetteGuerin(BCG)sears and effect of purified protein derivative(PPD)reaction anil to determine whether vitamin A(VA)combined vitamin I)(VD)supplementation influences the immune response to BCG revueeinated in Chinese infants.Methods:A cross-section and 3-month community-randomised trial was conducted.A total of 5 629 infants at 3,6 and 12 months of age in Junan County of China were examined for BCG scar fonnation.Then,597 revuccinated infants were randomly assigned to supplementation(n=307)and control(n=290)groups.The supplementation group were daily assigned to 1 500 IU VA and 500 IU VD for 3 months.Then all infants were subjected to skin test with PPD.Results:The diameter of BCG sears was positively con-elated with diameter of skin indurations of PPD(r=0.17,P<0.05)in the 5 629 infants.The rate of positive response to PP1)was higher in the supplementation group than in the control group(96.1%versus 89.7%,P<0.05,prevalence ratio 1.07.95%CI 1.02-1.12).The prevalence ralio of PPD response for the supplementation group compared with that for the control group was 1.07(95%CI 1.01-1.13)for the males and 1.08(95%CI 1.00-1.17)for the females.For the supplementation group,the males got larger tuberculin induration than the females[(0.73±0.2l)cm versus(0.67±0.20)cm.P<0.05)after intervention.Conclusions:The diameter of BCG scars was effectively correlated with PPD response,which indicates BCG scar formation may be an useful tool Io evaluate the effect of tuberculosis prevention.VA combined VD supplementation may play an immunoregulatory rale in BCG revuecination.This may contribute to the prevention of childhood tuberculosis. 展开更多
关键词 TUBERCULOSIS Bacille CALMETTE-GUERIN Purified protein derivative VITAMIN A VITAMIN D REVACCINATION
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Recent Developments in Hydrodynamic Cavitation Reactors:Cavitation Mechanism,Reactor Design,and Applications 被引量:5
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作者 Haoxuan zheng ying zheng Jesse Zhu 《Engineering》 SCIE EI CAS 2022年第12期180-198,共19页
Hydrodynamic cavitation is considered to be a promising technology for process intensification,due to its high energy efficiency,cost-effective operation,ability to induce chemical reactions,and scale-up possibilities... Hydrodynamic cavitation is considered to be a promising technology for process intensification,due to its high energy efficiency,cost-effective operation,ability to induce chemical reactions,and scale-up possibilities.In the past decade,advancements have been made in the fundamental understanding of hydrodynamic cavitation and its main variables,which provide a basis for applications of hydrodynamic cavitation in radical-induced chemical reaction processes.Here,we provide an extensive review of these research efforts,including the fundamentals of hydrodynamic cavitation,the design of cavitation reactors,cavitation-induced reaction enhancement,and relevant industrial applications.Two types of hydrodynamic cavitation reactors—namely,stationary and rotational—are compared.The design parameters of a hydrodynamic cavitation reactor and reactor performance at the laboratory and pilot scales are discussed,and recommendations are made regarding optimal operation and geometric conditions.The commercial cavitation reactors that are currently on the market are reviewed here for the first time.The unique features of hydrodynamic cavitation have been widely applied to various chemical reactions,such as oxidization reactions and wastewater treatment,and to physical processes,such as emulsion generation and component extraction.The roles of radicals and gas bubble implosion are also thoroughly discussed. 展开更多
关键词 Hydrodynamic cavitation Cavitation nuclei Hydroxyl radicals Stationary/rotational hydrodynamic cavitation reactor Reaction enhancement Cavitation application
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