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Trends of Superoxide Dismutase and Soluble Protein of Aquatic Plants in Lakes of Different Trophic levels in the Middle and Lower Reaches of the Yangtze River, China

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Journal of Integrative Plant Biology 2009年第4期51卷 414-422页

作者： Ai-Ping Wu Te Cao Shi-Kai Wu le-Yi ni Ping Xie Donghu Experimental Station of Lake Ecosystems The State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 China Ecology Department College of Bioscience and Biotechnology Hunan Agricultural University Changsha 410128 China Graduate University of the Wuhan Branch Chinese Academy of Sciences Wuhan 430072 China

A limnological study was carried out to determine the responses of superoxide dismutase （SOD） activities and soluble protein （SP） contents of 11 common aquatic plants to eutrophication stress. Field investigation in 12 lakes in the middle and lower reaches of the Yangtze River was carried out from March to September 2004. Our results indicated that non- submersed （emergent and floating-leafed） plants and submersed plants showed different responses to eutrophication stress. Both SOD activities of the non-submersed and submersed plants were negatively correlated with their SP contents （P 〈 0.000 1）. SP contents of non-submersed plants were significantly correlated with all nitrogen variables in the water （P 〈 0.05）, whereas SP contents of submersed plants were only significantly correlated with carbon variables as well as ammonium and Secchi depth （SD） in water （P 〈 0.05）. Only SOD activities of submersed plants were decreased with decline of SD in water （P 〈 0.001）. Our results indicate that the decline of SOD activities of submersed plants were mainly caused by light limitation, this showed a coincidence with the decline of macrophytes in eutrophic lakes, which might imply that the antioxidant system of the submersed plants were impaired under eutrophication stress.

关键词： eutrophication macrophytes soluble protein superoxide dismutase.

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Hydroxyl-terminated Polyethylenes Bearing Functional Side Groups:Facile Synthesis and Their Properties

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Chinese Journal of Polymer Science 2021年第8期39卷 994-1003,I0006页

作者： Wan-Bin Zhang Jie Luo Yan-Meng Wang Xiu-Zhong Zhu Ce Zhang Jing Liu Mei-le ni Guang-Hua Zhang Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science&TechnologyXi'an 710021China School of Light Industry and Engineering Qi Lu University of Technology(Shandong Academy of Sciences)Jinan 250353China

A series of hydroxyl-terminated polyethylenes(HTPE)bearing various functional side groups(***,ester and butane groups)were synthesized by the combination of ring opening metathesis polymerization(ROMP)and visible light photocatalytic thiol-ene *** products are named as a,w-dihydroxyl-polyllpropionyloxythio)methinetrimethylene](HTPECarboxy),a,w dihydroxy-poly(methylpropionatethio)methinetrimethylene](HTPEeser)and a,wdihydroxyl-poly[(butylthio)methinetrimethylene](HTPEbutane)*** investigation of ROMP indicated that the molecular weight of resultant hydroxy-terminated polybutadiene(HTPB)can be tailored by varying the feed ratios of monomer to chain transfer agent(CTA).The exploration of the photocatalytic thiol-ene reaction between HTPB precursor and methyl-3-mercaptopropionate revealed that blue light as well as oxygen accelerated the reaction.1H-NMR and 13C-NMR results verified all the double bonds in HTPB can be modified,and the main chain of resultant polymer can be considered as ***,relationship between the structure of side groups and the thermal properties of functional PEs was *** the results suggested that the Tg was in the order of HTPEbuaneles exhibited poor thermostability as compared to ***,the promising applications for functional PEs were ***1 can be utilized as a smart material with pH-responsive properties due to its pH-dependent ionization of carboxyl side *** can be employed as a macro-initiator for building the triblock copolymer due to the presence of active hydroxyl end *** can serve as a plasticizer for PVC which can enhance the ductilityt of PVC without obviously sacrificing strength.

关键词： Polyethylene Ring-opening metathesis polymerization Thiol-ene reaction Polybutadiene Structure property relationships

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Numerical Simulation of Integrative Flow Field for Hypersonic Vehicle

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Journal of Thermal Science 2001年第2期10卷 103-108页

作者： HE Yuanyuan le Jialing ni Hongli Computational Aerodynamic Institute, China Aerodynamic Research and Development Center, Mianyang Sichuan 621000, China Computational Aerodynamic Institute China Aerodynamic Research and Development Center Mianyang China

To meet the requirements for the aerodynamic performance and thrust force demanded in hypersonic missions, the integration design of fuselage and. engine must be considered for hypersonic vehicle with a scramjet engine. The configuration of wave rider is a typical hypersonic vehicle shape, whose fore-body can compress the flow in advance and provide uniform flow for the air intake, and whose aft-body,is used as an expansion surface of nozzle. In the present paper, an engineering method is applied to define total aerodynamic characteristics of an approximate wave rider configuration. A finite volume method based on the center of grid is also employed to numerically investigate the outflow pass the same configuration. The flow field details and the aerodynamic characteristics at given conditions are obtained. The evaluation for this configuration may be used as a guide for the hypersonic vehicle experiment.

关键词： hypersonic vehicle integration finite volume method.

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Histone modification landscape and the key significance of H3K27me3 in myocardial ischaemia/reperfusion injury

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Science China(Life Sciences) 2023年第6期66卷 1264-1279页

作者： le ni Bowen Lin Yanping Zhang Lingjie Hu Jianghua Lin Fengmei Fu Meiting Shen Can Li lei Chen Jian Yang Dan Shi Yi-Han Chen Department of Cardiology Shanghai East HospitalTongji University School of MedicineShanghai200120China Key Laboratory of Arrhythmias of the Ministry of Education of China Shanghai East HospitalTongji University School of MedicineShanghai200120China Department of Vascular and Cardiology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Jinzhou Medical University Liaoning121000China Shanghai Frontiers Science Center of Nanocatalytic Medicine Shanghai200092China Department of Pathology and Pathophysiology Tongji University School of MedicineShanghai200092China Research Units of Origin and Regulation of Heart Rhythm Chinese Academy of Medical SciencesShanghai200092China

Histone modifications play crucial roles in the pathogenesis of myocardial ischaemia/reperfusion(I/R)***,a genome-wide map of histone modifications and the underlying epigenetic signatures in myocardial I/R injury have not been ***,we integrated transcriptome and epigenome of histone modifications to characterize epigenetic signatures after I/R ***-specific histone mark alterations were mainly found in H3K27me3-,H3K27ac-,and H3K4me1-marked regions 24 and 48 h after I/*** differentially modified by H3K27ac,H3K4me1 and H3K27me3 were involved in immune response,heart conduction or contraction,cytoskeleton,and angiogenesis.H3K27me3 and its methyltransferase polycomb repressor complex 2(PRC2)were upregulated in myocardial tissues after I/*** selective inhibition of EZH2(the catalytic core of PRC2),the mice manifest improved cardiac function,enhanced angiogenesis,and reduced *** investigations confirmed that EZH2 inhibition regulated H3K27me3 modification of multiple pro-angiogenic genes and ultimately enhanced angiogenic properties in vivo and in *** study delineates a landscape of histone modifications in myocardial I/R injury,and identifies H3K27me3 as a key epigenetic modifier in I/R *** inhibition of H3K27me3 and its methyltransferase might be a potential strategy for myocardial I/R injury intervention.

关键词： histone modification myocardial ischemia/reperfusion EZH2 H3K27me3 angiogenesis

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The Place of Nursing Theory in the Management of Post-Operative Infections in a Hospital Environment: Case of Cibitoke District Hospital

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Open Journal of Nursing 2024年第5期14卷 225-238页

作者： Onésime Nduwimana le Béni Bugingo Arlette Ntigura Ishimwe Abias nibaruta Faculty of Health Sciences Hope Africa University Bujumbura Burundi Faculty of Health Sciences Integrated Polytechnic University Cibitoke Burundi

Introduction: Post-operative infections, such as surgical site infections (SSIs), are a significant concern in healthcare settings. Nurses play a crucial role in the prevention and management of these infections. The use of nursing theory could contribute to the prevention of SSIs. The aim of this study was to evaluate the role of nursing theory in the management of surgical site infections (SSIs) in a hospital environment. Method: A cross-sectional study was conducted using descriptive and analytical methods to assess the role of nursing theory in the management of Post-operative infections (POI) in a hospital setting in October 2023. The study population consisted of nurses working in the Surgery, Emergency, and Maternity units at Cibitoke District Hospital. A sample size of 71 nurses working full or part time in the Surgery were invited to participate in this study. A questionnaire was used to collect the data, and SPSS version 21.0 software was used for analysis. Results: The study found that nursing theory did not have any statistically significant place in the management of POI (p-value = 0.523). However, the results showed that experience was the only significant factor influencing the management of POI (p-value = 0.004). This is explained by the analysis of the net effects of the explanatory variable where we noticed that those who had more experience were more likely to manage post-operative infections. The participants’ knowledge regarding nursing theory in the management was poor as they scored less than 30% in all the variables used to measure their knowledge. Conclusion: The study revealed that nurses’ knowledge of nursing theories and their applications in the management of SSIs was poor. Continuing professional development, curriculum review, and in-service training were highly recommended.

关键词： Nurses Postoperative Infection Surgical Site Infections Management Nursing Theory

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拐点与抉择:中国电视业发展的历史逻辑与现实进路

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现代传播（中国传媒大学学报） 2019年第9期41卷 82-88页

作者：周勇倪乐融中国人民大学新闻学院党委中国人民大学新闻与社会发展研究中心中国人民大学新闻学院

以中观视角对电视业发展进行历时性研究,选取"频道"作为电视业发展历程的贯穿性要素和观察中国电视业兴衰逻辑的重要指标。基于时段资源开发的电视频道发展,历经资源匮乏、粗放扩张和饱和分化期,直至当下面临发展困局,究其根本是频道供... 详细信息

以中观视角对电视业发展进行历时性研究,选取"频道"作为电视业发展历程的贯穿性要素和观察中国电视业兴衰逻辑的重要指标。基于时段资源开发的电视频道发展,历经资源匮乏、粗放扩张和饱和分化期,直至当下面临发展困局,究其根本是频道供应的过度饱和导致供需失衡和以时间逻辑为主导的传统电视传播模式失效。拐点时刻的中国电视业需要直面后频道时代,在行业生态、传播模式、理念认知与价值链塑造等方面寻求脱离频道模式桎梏的未来进路。

关键词：电视史电视频道时段电视传播模式后频道时代

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盐酸帕罗西汀中R-异构体的HPLC测定

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中国医药工业杂志 2005年第3期36卷 161-162页

作者：张孝君倪乐平浙江尖峰药业有限公司浙江金华321000

建立了HPLC法测定盐酸帕罗西汀中R-异构体的含量。采用Chiral-AGP手性色谱柱,考察了流动相中有机溶剂的种类和比例、磷酸盐缓冲液浓度和pH值,以及柱温、流速对分离效果的影响。结果表明,以甲醇-0.04mol/L磷酸盐缓冲液(pH5.0)(10∶90)为... 详细信息

建立了HPLC法测定盐酸帕罗西汀中R-异构体的含量。采用Chiral-AGP手性色谱柱,考察了流动相中有机溶剂的种类和比例、磷酸盐缓冲液浓度和pH值,以及柱温、流速对分离效果的影响。结果表明,以甲醇-0.04mol/L磷酸盐缓冲液(pH5.0)(10∶90)为流动相,流速0.8ml/min,检测波长293nm,盐酸帕罗西汀与其R-异构体能完全分离,两者检测限均为10ng。

关键词：帕罗西汀 R-异构体高效液相色谱测定

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Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm

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Energy Engineering 2025年第1期122卷 265-284页

作者： Chao Zhou NarisuWang Fuyin ni Wenchao Zhang School of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou213001China Jiangsu Key Laboratory of Power Transmission&Distribution Equipment Technology Jiangsu University of TechnologyChangzhou213001China

Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island *** response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization *** proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop ***,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control *** pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid ***,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee *** operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load *** strategy effectively mitigated transient voltage and current surges during mode ***,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid *** enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability.

关键词： Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching

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Clinical Preceptor’s Role in the Development of Nursing Training Based on Professional and Competency Frameworks in Two Health Care Facilities of Bujumbura

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Open Journal of Nursing 2021年第6期11卷 528-541页

作者： Ismaël nicoyishimiye Emmanuel Gasaba Jackson niyonzima Claudine Nshimirimana Jeanine Ndayizeye Médiatrice Nkurunziza le Béni Bugingo Edouard niyongabo Faculty of Health Sciences Hope Africa University Bujumbura Burundi Department of Public Health Sciences National Institute of Public Health Bujumbura Burundi

Background: The aim of clinical preceptors is to support the development of expertise related to the preceptorship of groups of trainees among nurses in clinical settings by the acquisition and use of theoretical knowledge, know-how and know-that. The support of students remains a major problem in hospitals, because the requirements of the preceptors according to the standards are not considered. The lack of guidelines on nursing preceptorships, theoretical application based on the professional curriculum, and professional expertise were the main problems assessed in the two Health Care (HUCK, VNC) in this study. The purpose of this study is to assess the knowledge of nurses and learners during their preceptorship practices and to contribute to the direction of evidence-based preceptorship. Method: A descriptive cross-sectional study design was used in this study during the 3-month period. A sample of 121 nurses as well as 56 learners were selected from 381 nurses and 80 learners using Alain Bouchard’s formula. A questionnaire developed according to the guidelines of Ernestine Wiedenbach’s theory of care, was distributed. The data were analyzed using the Microsoft Excel and the software program version 16 (SPSS-16). Results: The current study found that the majority of nurses do not know the importance of the clinical tutor. The results state that students experience clinical practice problems, thus clinical preceptorship is required. Nurses showed that there are different barriers often encountered during their practices. The overall nurse preceptorship process is not optimal and the average of 97.6% of nurses does not have expertise in coaching interns in clinical settings. Conclusion: Although that nurses have some experience at work, they express their weakness based on a low level of education, a lack of knowledge and trained professionals on the job, and clinical preceptorship guidelines.

关键词： Clinical Preceptor Clinical Support Nursing Training Healthcare Facilities

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长江中游浅水湖泊水生植物氮磷含量与水柱营养的关系

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水生生物学报 2005年第4期29卷 406-412页

作者：吴爱平吴世凯倪乐意中国科学院水生生物研究所东湖湖泊生态系统试验站武汉430072

水生植物组织内氮和磷(N和P)含量受到水体营养状况和植物生长状况影响。对长江中游江汉湖群不同营养水平湖泊中大型水生植物的N和P含量3个季度的研究表明,在不同生活型水生植物中,沉水植物主要分布在中营养到中富营养湖泊中,在富营养湖... 详细信息

水生植物组织内氮和磷(N和P)含量受到水体营养状况和植物生长状况影响。对长江中游江汉湖群不同营养水平湖泊中大型水生植物的N和P含量3个季度的研究表明,在不同生活型水生植物中,沉水植物主要分布在中营养到中富营养湖泊中,在富营养湖泊均无分布,浮叶和挺水植物在不同营养类型湖泊的沿岸带均有分布。N和P含量以沉水植物最高,浮叶植物次之,挺水植物最低。水生植物的N和P含量都达到或超过生长所需最低N和P阈值,代表性浮叶植物和沉水植物的N和P含量随着湖泊营养水平提高呈现规律性变化。湖泊5种常见的水生植物N和P含量与水柱中不同种类N和P浓度具有季节性相关:菱(TrapabispinosaRoxb.)春夏季P含量都与TP(总磷)和TDP(总溶解磷)明显相关,春季N含量与NH4—N(氨氮)明显相关;春季黄丝草(***.)的P含量与TP明显相关,夏季与TDP明显相关,春季和夏季黄丝草和穗花狐尾藻(MyriophyllumspicatumL.)的N含量与TN(总氮)和TDN(总溶解氮)显著正相关,秋季成负相关;夏季芦苇(PhragmitescommunisTrin.)P含量与TP和TDP显著相关;春季芦苇和香蒲(TyphaorientalisPresl.)N含量与NH4N和NO2N(亚硝态氮)显著相关。

关键词：水生植物氮磷含量相关关系营养类型长江中游地区浅水湖泊水质监测

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