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Contractor-Related Factors and Performance of Bridge Construction Projects Implemented by Kenya National Highways Authority (KeNHA) Kenya
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作者 Joan Anyika Otike Charles Kabubo Victoria Okumu 《Open Journal of Civil Engineering》 2024年第2期214-224,共11页
The performance of bridge projects in Kenya is poor in terms of completion by schedule, cost, and quality (scope). Yet, there is less evidence of empirical research on what factors contribute to this outcome. This stu... The performance of bridge projects in Kenya is poor in terms of completion by schedule, cost, and quality (scope). Yet, there is less evidence of empirical research on what factors contribute to this outcome. This study aimed to bridge this gap by examining the effects of contractor-related factors on the performance of bridge construction projects in Kenya through a case study of the Bridge projects Implemented by the Kenya National Highway Agency (KeNHA). The theory of constraints (TOC) was adopted as its theoretical framework. Descriptive research was used, and the target population was 18 bridge construction projects, which were the units of analysis from 2012 to 2022. In each of these projects, 18 respondents, namely clients, consultants, contractors, engineers, environment and social guards, project managers, stakeholders, subcontractors, technical advisors, and inspectors, were included in a target population of 144 respondents. A census was conducted and a structured questionnaire was administered from which a response rate of 68% was achieved. The information was analyzed using descriptive, correlation, and multiple linear regression analysis. The contractor-related factors considered in the study were staff and management factors. The findings indicated that staff and management factors had a positive and significant outcome on performance of bridge construction projects. The study recommends continuous training and a safe learning environment for staff to improve their skills and performance in future projects. The study also recommends that a special category for bridge contractors be created in Kenya’s National Construction Authority rankings to ensure that only qualified contractors implement the Bridge projects. 展开更多
关键词 Staff Factors Management Factors Performance Bridge projects KeNHA
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Multi-Criteria Wildfire Risk Hazard Assessment in GIS Environment: Projection for the Future and Impact on RES Projects Installation Planning
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作者 Aggelos Pallikarakis Flora Konstantopoulou 《Journal of Geoscience and Environment Protection》 2024年第5期242-265,共24页
It is alarming for the fact that Wildfires number, severity and consequently impact have significantly increased during the last years, an aftermath of the Climate Change. One of the most affected areas worldwide is M... It is alarming for the fact that Wildfires number, severity and consequently impact have significantly increased during the last years, an aftermath of the Climate Change. One of the most affected areas worldwide is Mediterranean, due to the unique combination of its type of vegetation and demanding climatic conditions. This research is focused on the Region of Epirus in Greece, an area with significant natural vegetation and a range of geomorphological aspects. In order to estimate the Wildfire Risk Hazard, several factors have been used: geomorphological (slope, aspect, elevation, TWI, Hydrographic network), social (Settlements and landfils, roads, overhead lines and substations), environmental (land cover) and climatic (Fire Weather Index). Through a multi-criteria decision analysis (MCDA) and an analytic hierarchy process (AHP) in a GIS environment, the Wildfire Risk Hazard has been estimated not only for current conditions but also for future projections for the near future (2031-2060) and the far future (2071-2100). The selected case study includes the potential impact of the Wildfires to the installed (or targeted to be installed) RES projects in the studied region. 展开更多
关键词 RES projects Greece Epirus Analytic Hierarchy Process Multi-Criteria Decision Analysis
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A Review on Determinants Affecting Commercialization of Academic Institution Final Year Projects
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作者 Xin Lan Zaheril Bin Zainudin 《Journal of Sustainable Business and Economics》 2024年第2期44-61,共18页
Final year project is an important training and assessment component incorporated in many courses of academic institution.The ability to translate ideas,research,and creativity into actual products,services,or busines... Final year project is an important training and assessment component incorporated in many courses of academic institution.The ability to translate ideas,research,and creativity into actual products,services,or businesses shows how successful and impactful people or institutions can be in the wider economy.However,in most of the cases,the outcomes of the final year project usually remain as academic discussion without maximizing their potential to be converted into a commercialized product or services.In this review,theory and applications are discussed to understand how entrepreneurial skills and networking abilities,components of individuals’human capital can impact the commercialisation of final year projects.Furthermore,determinants affecting commercialization of final year projects will also be explored namely:entrepreneurial skills,networking ability,access to resources,institutional support as well as creativity and innovation. 展开更多
关键词 COMMERCIALIZATION Final Year projects ENTREPRENEURSHIP Institution Support Network Resources
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Exploration of the Maturity Evaluation of College Students’Innovation and Entrepreneurship Projects Based on Computer Database Technology
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作者 Shuai Yuan 《Journal of Electronic Research and Application》 2024年第6期89-95,共7页
The college innovation and entrepreneurship program is a powerful means to enhance students’innovation and entrepreneurship skills.Evaluating the maturity of innovation and entrepreneurship projects can stimulate stu... The college innovation and entrepreneurship program is a powerful means to enhance students’innovation and entrepreneurship skills.Evaluating the maturity of innovation and entrepreneurship projects can stimulate students’enthusiasm and initiative to participate.Utilizing computer database technology for maturity evaluation can make the process more efficient,accurate,and convenient,aligning with the needs of the information age.Exploring strategies for applying computer database technology in the maturity evaluation of innovation and entrepreneurship projects offers valuable insights and directions for developing these projects,while also providing strong support for enhancing students’innovation and entrepreneurship abilities. 展开更多
关键词 DATABASE Innovation and entrepreneurship projects Maturity evaluation
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Financial Calculation Problems and Countermeasure Analysis of Large-Scale Engineering Construction Projects
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作者 Qiong Hou 《Proceedings of Business and Economic Studies》 2024年第2期15-21,共7页
The financial aspects of large-scale engineering construction projects profoundly influence their success.Strengthening cost control and establishing a scientific financial evaluation system can enhance the project’s... The financial aspects of large-scale engineering construction projects profoundly influence their success.Strengthening cost control and establishing a scientific financial evaluation system can enhance the project’s economic benefits,minimize unnecessary costs,and provide decision-makers with a robust financial foundation.Additionally,implementing an effective cash flow control mechanism and conducting a comprehensive assessment of potential project risks can ensure financial stability and mitigate the risk of fund shortages.Developing a practical and feasible fundraising plan,along with stringent fund management practices,can prevent fund wastage and optimize fund utilization efficiency.These measures not only facilitate smooth project progression and improve project management efficiency but also enhance the project’s economic and social outcomes. 展开更多
关键词 Large-scale engineering construction projects Financial calculation Fund management
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Trust beyond Technology Algorithms: A Theoretical Exploration of Consumer Trust and Behavior in Technological Consumption and AI Projects
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作者 David Oyekunle Ugochukwu Okwudili Matthew +1 位作者 David Preston David Boohene 《Journal of Computer and Communications》 2024年第6期72-102,共31页
In an era dominated by artificial intelligence (AI), establishing customer confidence is crucial for the integration and acceptance of AI technologies. This interdisciplinary study examines factors influencing custome... In an era dominated by artificial intelligence (AI), establishing customer confidence is crucial for the integration and acceptance of AI technologies. This interdisciplinary study examines factors influencing customer trust in AI systems through a mixed-methods approach, blending quantitative analysis with qualitative insights to create a comprehensive conceptual framework. Quantitatively, the study analyzes responses from 1248 participants using structural equation modeling (SEM), exploring interactions between technological factors like perceived usefulness and transparency, psychological factors including perceived risk and domain expertise, and organizational factors such as leadership support and ethical accountability. The results confirm the model, showing significant impacts of these factors on consumer trust and AI adoption attitudes. Qualitatively, the study includes 35 semi-structured interviews and five case studies, providing deeper insight into the dynamics shaping trust. Key themes identified include the necessity of explainability, domain competence, corporate culture, and stakeholder engagement in fostering trust. The qualitative findings complement the quantitative data, highlighting the complex interplay between technology capabilities, human perceptions, and organizational practices in establishing trust in AI. By integrating these findings, the study proposes a novel conceptual model that elucidates how various elements collectively influence consumer trust in AI. This model not only advances theoretical understanding but also offers practical implications for businesses and policymakers. The research contributes to the discourse on trust creation and decision-making in technology, emphasizing the need for interdisciplinary efforts to address societal challenges associated with technological advancements. It lays the groundwork for future research, including longitudinal, cross-cultural, and industry-specific studies, to further explore consumer trust in AI. 展开更多
关键词 Consumer Trust AI-Driven projects TRANSPARENCY Ethical Accountability Structural Equation Modeling (SEM) Technology Acceptance Model (TAM) Interdisciplinary Study Organizational Factors Psychological Factors Behavioral Intention
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Research on Intelligent Cost Estimation of Engineering Foundation Projects Based on CSIs Theory
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作者 Jie Di Wenhao Xing +2 位作者 Meng Wu Dan Zhang Jiashuo Zhao 《Journal of World Architecture》 2024年第5期29-35,共7页
Against the backdrop of rapid development in China’s construction and infrastructure sectors,discrepancies between project budgets and actual costs have become pronounced,manifesting in project overruns and suspensio... Against the backdrop of rapid development in China’s construction and infrastructure sectors,discrepancies between project budgets and actual costs have become pronounced,manifesting in project overruns and suspensions,posing significant challenges.To address inaccuracies in investment targets and operational complexities,this study focuses on a beam-bridge construction project in a district of Shijiazhuang city as a case study.Drawing upon historical analogs,the project employs a Work Breakdown Structure(WBS)to decompose the engineering works.Building on theories of Cost Significant(CS)and Whole Life Costing(WLC),the study constructs Cost Significant Items(CSIs)and develops a CNN-BiLSTM-Attention neural network for nonlinear prediction.By identifying significant cost drivers in engineering projects,this paper presents a streamlined cost estimation method that significantly reduces computational burdens,simplifies data collection processes,and optimizes data analysis and forecasting,thereby enhancing prediction accuracy.Finally,validation with real-world cost fluctuation data demonstrates minor errors,meeting predictive requirements across project execution phases. 展开更多
关键词 project management Cost Significant Items(CSIs) Engineering costing Intelligent estimation
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Construction Safety Management of Mechanical and Electrical Installation Projects
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作者 Honglou Chi 《Journal of Architectural Research and Development》 2024年第2期50-54,共5页
Various industries today rely on the support of electromechanical equipment,expanding its scope of application and leading to an increase in electromechanical installation projects.However,due to the high level of exp... Various industries today rely on the support of electromechanical equipment,expanding its scope of application and leading to an increase in electromechanical installation projects.However,due to the high level of expertise required and the potential risks involved,it is crucial to emphasize safety management during construction.This paper delves into the significance of construction safety management for electromechanical installation projects,identifies common problems encountered during construction,and proposes solutions.This analysis aims to provide relevant personnel with essential guidance and references for managing electromechanical installation projects safely. 展开更多
关键词 Construction safety Mechanical and electrical installation Installation engineering Engineering projects Safety management
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非小细胞肺癌患者血清CA211水平和NK细胞数与预后相关 被引量:1
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作者 丁飞 王洒 黄常新 《基础医学与临床》 2024年第2期180-184,共5页
目的 探究非小细胞肺癌(NSCLC)患者血清糖类抗原211(CA211)表达水平和自然杀伤(NK)细胞数与预后的相关性。方法 选取杭州师范大学附属医院2019年6月至2022年7月收治的132例NSCLC患者作为实验组,另选取同期收治的132例肺部良性病变患者... 目的 探究非小细胞肺癌(NSCLC)患者血清糖类抗原211(CA211)表达水平和自然杀伤(NK)细胞数与预后的相关性。方法 选取杭州师范大学附属医院2019年6月至2022年7月收治的132例NSCLC患者作为实验组,另选取同期收治的132例肺部良性病变患者作为对照组。从检验科收集数据分析NSCLC患者血清CA211表达水平和NK细胞数与患者预后关系以及影响NSCLC患者预后的相关因素。结果 实验组中性粒细胞/淋巴细胞值(NLR值)和血清CA211表达水平高于对照组(P<0.05),NK细胞数低于对照组(P<0.05);实验组血清CA211表达水平和NK细胞数呈负相关(r=-0.405,P<0.001);不同血清CA211表达水平和NK细胞数的患者淋巴结转移情况以及TNM分期存在显著性差异(P<0.05);CA211低表达者1年生存率高于CA211高表达者(P<0.05),NK细胞高水平者1年生存率高于NK细胞低水平者(P<0.05);淋巴结转移、TNM分期、CA211是影响NSCLC患者预后的危险因素(P<0.05),NK细胞是NSCLC患者预后的保护因素(P<0.05)。结论 NSCLC患者血清CA211表达水平及NK细胞数与临床病理特征及预后有密切联系。 展开更多
关键词 非小细胞肺癌 糖类抗原211 自然杀伤细胞 预后
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circFAT1调节miR-211-5p/CCND2轴对糖尿病心肌病大鼠心肌损伤的影响
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作者 谷君 许峥嵘 +3 位作者 史丽 任卫东 左丽娟 张秋子 《中国医科大学学报》 CAS 北大核心 2024年第6期516-524,共9页
目的探讨circFAT1对糖尿病心肌病(DCM)大鼠心肌损伤的影响及对miR-211-5p/细胞周期蛋白D2(CCND2)轴的调节机制。方法利用高糖高脂饲料联合链脲佐菌素建立DCM大鼠模型,并随机分为DCM组、circ-NC组、circFAT1组、circFAT1+激动剂-NC组和ci... 目的探讨circFAT1对糖尿病心肌病(DCM)大鼠心肌损伤的影响及对miR-211-5p/细胞周期蛋白D2(CCND2)轴的调节机制。方法利用高糖高脂饲料联合链脲佐菌素建立DCM大鼠模型,并随机分为DCM组、circ-NC组、circFAT1组、circFAT1+激动剂-NC组和circFAT1+miR-211-5p激动剂组,以喂食普通饲料的大鼠作为对照组,每组20只。实时PCR检测心肌组织中circFAT1、miR-211-5p、CCND2水平;Western blotting检测心肌组织CCND2蛋白表达;生化分析仪检测大鼠空腹血糖(FBG)、总胆固醇(TC)和甘油三酯(TG)水平;心脏超声检测大鼠心功能;HE和Masson染色观察心肌组织病理形态;TUNEL染色检测心肌细胞凋亡情况;ELISA法检测白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平;双荧光素酶报告基因实验验证circFAT1、miR-211-5p、CCND2之间的靶向关系。结果与对照组相比,DCM组circFAT1、CCND2 mRNA及蛋白表达,左心室射血分数(LVEF)、左心室缩短分数(LVFS)水平降低(P<0.05),FBG、TC、TG、左心室舒张末期直径(LVEDd)、左心室收缩末期直径(LVEDs)、胶原容积分数(CVF)、细胞凋亡率、IL-1β、IL-6、TNF-α水平均升高(P<0.05);与DCM组相比,circFAT1组circFAT1、CCND2 mRNA及蛋白表达,LVEF、LVFS水平升高(P<0.05),FBG、TC、TG、LVEDd、LVEDs、CVF、细胞凋亡率、IL-1β、IL-6、TNF-α水平降低(P<0.05);miR-211-5p激动剂逆转了circFAT1对DCM心肌损伤的缓解作用,且CCND2 mRNA及蛋白表达降低(P<0.05)。结论circFAT1通过调控miR-211-5p/CCND2轴减轻DCM大鼠心肌组织损伤。 展开更多
关键词 circFAT1 miR-211-5p 细胞周期蛋白D2 糖尿病心肌病 心肌损伤
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血清CYFRA211、CA153、AFP联合检测在卵巢癌诊断中的应用价值
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作者 李珊珊 《哈尔滨医药》 2024年第2期79-81,共3页
目的探究血清细胞角蛋白19血清片段211(CYFRA211)、糖类抗原153(CA153)、甲胎蛋白(AFP)联合检测在卵巢癌诊断中的应用价值。方法回顾性选取进行手术治疗的卵巢肿瘤85例患者的临床资料,按术后病理结果分为恶性肿瘤51例(Ⅰ期11例,Ⅱ期10例... 目的探究血清细胞角蛋白19血清片段211(CYFRA211)、糖类抗原153(CA153)、甲胎蛋白(AFP)联合检测在卵巢癌诊断中的应用价值。方法回顾性选取进行手术治疗的卵巢肿瘤85例患者的临床资料,按术后病理结果分为恶性肿瘤51例(Ⅰ期11例,Ⅱ期10例,Ⅲ期18例,Ⅳ期12例),设为恶性组,剩余34例均为良性肿瘤,设为良性组,并同期选取30例于本院妇科进行体检的女性,作为对照组,收集卵巢肿瘤患者术后及对照组相关实验室数据资料,比较三组研究对象、恶性肿瘤不同分期患者血清CYFRA211、CA153、AFP水平差异,并分析血清CYFRA211、CA153、AFP联合检测卵巢癌的诊断价值。结果三组血清CYFRA211、CA153、AFP水平比较,差异有统计学意义(P<0.05)。恶性组各血清学指标水平均明显高于良性组、对照组,良性组血清学指标水平明显高于对照组,差异均有统计学意义(P<0.05)。不同分期的恶性肿瘤患者血清CYFRA211、CA153、AFP水平比较,差异有统计学意义(P<0.05),且各指标水平随分期升高而升高;血清CYFRA211、CA153、AFP及联合检测诊断卵巢癌的灵敏度分别为82.35%、86.27%、94.11%、68.43%,特异度分别为70.59%、78.41%、94.11%、68.43%;其中AFP检测灵敏度最高,三项联合检测的特异度明显高于单项检测,差异均有统计学意义(P<0.05)。结论卵巢癌会导致患者血清CYFRA211、CA153、AFP水平明显升高,血清CYFRA211、CA153、AFP水平对于诊断卵巢癌具有一定诊断效能,且联合诊断特异度更好。 展开更多
关键词 卵巢癌 细胞角蛋白19血清片段211 糖类抗原153 甲胎蛋白 诊断效能
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211Z.1铝合金微观组织及力学性能研究
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作者 张中可 车云 +1 位作者 门三泉 李祥 《贵州科学》 2024年第4期93-96,共4页
主要对211Z.1铝合金材料进行了金属型铸造加工及力学性能测试。实验结果显示,制备出的铸造试棒表面光滑,无铸造缺陷。经过T5热处理工艺之后,其平均抗拉强度达到了349.8 MPa,断后延伸率为21.3%,布氏硬度100,展现出优良的力学性能。通过... 主要对211Z.1铝合金材料进行了金属型铸造加工及力学性能测试。实验结果显示,制备出的铸造试棒表面光滑,无铸造缺陷。经过T5热处理工艺之后,其平均抗拉强度达到了349.8 MPa,断后延伸率为21.3%,布氏硬度100,展现出优良的力学性能。通过光学显微镜(OM)、扫描电子显微镜(SEM)等技术手段,实施了对合金微观结构的深入分析,探索了微观组织对合金力学性能的影响,并揭示了其性能的内在联系。本研究结果为211Z.1铝合金在工程领域的应用以及未来材料设计方面提供了理论探索和实践指引。 展开更多
关键词 211Z.1铝合金 微观组织 力学性能
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用于^(211)At生产的高功率金属Bi靶热效应模拟
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作者 熊杰 窦国梁 +5 位作者 孙良亭 王洋 秦芝 任洁茹 赵永涛 赵红卫 《强激光与粒子束》 CAS CSCD 北大核心 2024年第9期88-93,共6页
为提高用于医用同位素^(211)At生产的金属Bi靶在高束流功率作用下的可靠性与使役寿命,对多种束流均匀化方法进行了模拟与对比,利用计算流体力学(CFD)方法模拟分析了在wobbler磁铁作用下强度为500 eμA的α束流轰击Bi靶产生的热效应,为... 为提高用于医用同位素^(211)At生产的金属Bi靶在高束流功率作用下的可靠性与使役寿命,对多种束流均匀化方法进行了模拟与对比,利用计算流体力学(CFD)方法模拟分析了在wobbler磁铁作用下强度为500 eμA的α束流轰击Bi靶产生的热效应,为靶系统的设计和寿命的延长提供了关键技术支撑。结果表明,通过扫描实现束流均匀化可大幅降低靶上的最大热功率密度;在靶前采用wobbler磁铁对束流进行周期性圆扫描可有效降低Bi靶的表面温度。当扫描频率为50 Hz时,Bi靶最高温度为189.8℃,低于其熔点(271.3℃),能够满足Bi靶在此高功率束流照射下安全运行的温度要求。 展开更多
关键词 Bi靶 α离子束 At-211 同位素生产 计算流体力学
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^(211)At干馏装置研制及分离工艺研究
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作者 覃贻琳 刘葳豪 +5 位作者 叶天真 杨远友 李飞泽 兰图 廖家莉 刘宁 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第4期742-750,共9页
^(211)At是一种α核素,其半衰期为7.2 h,不仅适用于α靶向内放射治疗,也可替代长半衰期核素用于α辐解的研究。为解决现有^(211)At干馏工艺产额低、稳定性差的问题,本研究优化设计了^(211)At干馏生产工艺,集成了一套半自动化^(211)At干... ^(211)At是一种α核素,其半衰期为7.2 h,不仅适用于α靶向内放射治疗,也可替代长半衰期核素用于α辐解的研究。为解决现有^(211)At干馏工艺产额低、稳定性差的问题,本研究优化设计了^(211)At干馏生产工艺,集成了一套半自动化^(211)At干馏分离装置。采用碘干馏模拟实验确定了影响干馏分离的主要影响因素,改进得到了简便可行的^(211)At干馏分离工艺步骤。^(211)At干馏分离结果表明:当加速器α束流强度为20μA、能量为28.5 MeV时,轰击Bi靶4 h后,^(211)At的3次平均产额为17.87 mCi(6.61×10^(8) Bq),产品核纯度>99.9%,无Bi、Cu等杂质。^(211)At收率达98%以上,分离耗时45~60 min。本研究不仅为各类^(211)At应用工作的开展垫定了良好的基础,也可为后续^(211)At干馏自动化装置的研制提供参考。 展开更多
关键词 ^(211)At 干馏分离 工艺 碘模拟工艺 干馏装置
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磁共振弥散加权成像联合血清CYFRA211在直肠癌术前分期诊断中的应用价值 被引量:1
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作者 李晓成 孟宪平 费锋 《中国医药导报》 CAS 2024年第4期21-24,69,共5页
目的 分析磁共振弥散加权成像(MRI-DWI)联合血清CYFRA211在直肠癌术前分期诊断中的应用价值。方法 回顾性分析2020年1月至2023年4月东南大学医学院附属江阴医院收治的124例直肠癌患者的临床资料。以病理结果为金标准,分析MRI-DWI联合血... 目的 分析磁共振弥散加权成像(MRI-DWI)联合血清CYFRA211在直肠癌术前分期诊断中的应用价值。方法 回顾性分析2020年1月至2023年4月东南大学医学院附属江阴医院收治的124例直肠癌患者的临床资料。以病理结果为金标准,分析MRI-DWI联合血清CYFRA211对直肠癌术前T、N分期的诊断价值。结果 病理结果显示,124例直肠癌患者中,T_(1)期16例、T_(2)期14例、T_(3)期46例、T_(4)期48例;N_(0)期54例、N_(1)期40例、N_(2)期30例。T_(4)期患者血清CYFRA211高于T_(1)、T_(2)、T_(3)期,T_(3)期患者血清CYFRA211高于T_(1)、T_(2)期,T_(2)期患者血清CYFRA211高于T_(1)期(P<0.05)。N_(2)期患者血清CYFRA211高于N_(0)、N_(1)期,N_(1)期患者血清CYFRA211高于N_(0)期(P<0.05)。血清CYFRA211诊断直肠癌术前T_(1)、T_(2)、T_(3)、T_(4)、N_(0)、N_(1)、N_(2)期曲线下面积分别为0.756、0.744、0.805、0.897、0.791、0.813、0.821。MRI-DWI对术前T_(1)、T_(2)、T_(3)、T_(4)期的诊断一致性一般(Kappa=0.452、0.587、0.672、0.720,P<0.01);MRI-DWI联合血清CYFRA211对术前T_(1)、T_(2)、T_(3)、T_(4)期的诊断一致性较好(Kappa=0.768、0.785、0.827、0.839,P<0.01)。MRI-DWI对术前N_(0)、N_(1)、N_(2)期的诊断一致性一般(Kappa=0.473、0.598、0.682,P<0.01),MRI-DWI联合血清CYFRA211对术前N_(0)、N_(1)、N_(2)期的诊断一致性较好(Kappa=0.795、0.821、0.834,P<0.01)。结论 MRI-DWI联合血清CYFRA211在直肠癌术前T、N分期的诊断价值更高。 展开更多
关键词 磁共振弥散加权成像 CYFRA211 直肠癌 术前分期
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Impact of estuarine reclamation projects on saltwater intrusion and freshwater resource 被引量:1
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作者 Hanghang LU Jianrong ZHU +3 位作者 Qing CHEN Ming LI Shunqi PAN Shenliang CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期38-56,共19页
Estuarine projects can change local topography and influence water transport and saltwater intrusion.The Changjiang(Yangtze)River estuary is a multichannel estuary,and four major reclamation projects have been impleme... Estuarine projects can change local topography and influence water transport and saltwater intrusion.The Changjiang(Yangtze)River estuary is a multichannel estuary,and four major reclamation projects have been implemented in the Changjiang River estuary in recent years:the Xincun Shoal reclamation project(RP-XCS),the Qingcao Shoal reclamation project(RP-QCS),the Eastern Hengsha Shoal reclamation project(RP-EHS),and the Nanhui Shoal reclamation project(RP-NHS).The effects of the four reclamation projects and each project on the saltwater intrusion and water resources in the Changjiang River estuary were simulated in a 3D numerical model.Results show that for a multichannel estuary,local reclamation projects change the local topography and water diversion ratio(WDR)between channels and influence water and salt transport and freshwater utilization in the estuary.During spring tide,under the cumulative effect of the four reclamation projects,the salinity decreases by approximately 0.5in the upper reaches of the North Branch and increases by 0.5-1.0 in the middle and lower reaches of the North Branch.In the North Channel,the salinity decreases by approximately 0.5.In the North Passage,the salinity increases by 0.5-1.0.In the South Passage,the salinity increases by approximately 0.5 in the upper reaches and decreases by 0.2-0.5 on the north side of the middle and lower reaches.During neap tide,the cumulative effects of the four reclamation projects and the individual projects are similar to those during spring tide,but there are some differences.The effects of an individual reclamation project on WDR and saltwater intrusion during spring and neap tides are simulated and analyzed in detail.The cumulative effect of the four reclamation projects favors freshwater usage in the Changjiang River estuary. 展开更多
关键词 reclamation projects saltwater intrusion freshwater resources numerical model Changjiang River estuary
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皮肤恶性黑色素瘤血清miR-211、miR-128水平及与疗效关系
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作者 刘月丽 朱林 +1 位作者 魏星 吴勇 《分子诊断与治疗杂志》 2024年第1期178-182,共5页
目的探究皮肤恶性黑色素瘤(CMM)血清miR-211、miR-128水平及与疗效关系。方法选取2021年7月至2022年6月期间河南中医药大学第三附属医院收治的120例CMM患者为CMM组,选取同期90例非肿瘤皮肤病患者为对照组,比较两组血清miR-211、miR-128... 目的探究皮肤恶性黑色素瘤(CMM)血清miR-211、miR-128水平及与疗效关系。方法选取2021年7月至2022年6月期间河南中医药大学第三附属医院收治的120例CMM患者为CMM组,选取同期90例非肿瘤皮肤病患者为对照组,比较两组血清miR-211、miR-128表达水平,分析血清miR-211、miR-128表达与CMM临床病理特征关系;3个月后,根据CMM组患者实体瘤疗效分为缓解组和未缓解组,分析血清miR-211、miR-128表达与患者疗效关系。结果CMM组血清miR-211、miR-128表达量低于对照组,差异有统计学意义(t=18.186、48.871,P均<0.05)。不同病理类型、分化程度、淋巴结转移、临床分期、Ki-67指数患者血清miR-211表达比较差异有统计学意义(F或t=13.209、3.044、5.601、7.996、3.748,P均<0.05),不同分化程度、淋巴结转移、临床分期患者血清miR-128表达比较差异有统计学意义(t=5.940、9.592、12.895,P均<0.05)。缓解组与未缓解组病理类型、分化程度、有无淋巴结转移、临床分期、Ki-67指数水平、是否手术比较差异均有统计学意义(χ^(2)=8.062、19.171、7.333、14.436、5.025、4.309,P均<0.05);治疗后,缓解组血清miR-211、miR-128表达均高于未缓解组,差异有统计学意义(t=13.926、8.849,P均<0.05)。多因素Logistic回归分析显示,低分化(OR=2.275,95%CI:1.027~5.042)、淋巴结转移(OR=2.643,95%CI:1.243~5.622)、临床分期Ⅲ~Ⅳ期(OR=3.022,95%CI:1.348~6.777)、miR-211低表达(OR=2.208,95%CI:1.217~4.006)、miR-128低表达(OR=2.375,95%CI:1.086~5.192)是影响患者疗效的危险因素(P<0.05)。结论CMM患者血清miR-211、miR-128表达水平明显降低,两指标均与患者临床病理特征及疗效有关,具有一定参考价值。 展开更多
关键词 皮肤恶性黑色素瘤 微小RNA-211 微小RNA-128 临床病理特征
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miR-211-5p和miR-202-3p在抑郁症患者中的表达及其与患者病情程度和认知功能的关系
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作者 张果 赵方方 何丹丹 《成都医学院学报》 CAS 2024年第4期624-627,632,共5页
目的探究微小核糖核酸-211-5p(miR-211-5p)和微小核糖核酸-202-3p(miR-202-3p)在抑郁症患者中的表达及其与患者病情程度和认知功能的关系。方法选取2021年1月至2023年6月郑州大学第一附属医院精神科收治的92例确诊为抑郁症的患者为抑郁... 目的探究微小核糖核酸-211-5p(miR-211-5p)和微小核糖核酸-202-3p(miR-202-3p)在抑郁症患者中的表达及其与患者病情程度和认知功能的关系。方法选取2021年1月至2023年6月郑州大学第一附属医院精神科收治的92例确诊为抑郁症的患者为抑郁症组,同期选取本院体检健康(精神状态正常)的志愿者92例为对照组。根据抑郁自评量表(SDS)分为轻度抑郁组(SDS:53~62分)45例、中度抑郁组(SDS:63~72分)30例、重度抑郁组(SDS:73分及以上)17例。根据简易智力状态检查量表(MMSE)评分分为轻度认知功能障碍组(MMSE:21~26分)24例、中度认知功能障碍组(MMSE:10~20分)40例、重度认知功能障碍组(MMSE:1~9分)28例。实时荧光定量聚合酶链反应检测miR-211-5p和miR-202-3p水平。血清miR-211-5p、miR-202-3p水平对抑郁症的诊断价值采用ROC曲线进行分析。血清miR-211-5p、miR-202-3p水平与病情程度及认知功能的关系采用Spearman相关性分析。结果抑郁症患者血清miR-211-5p水平低于对照组,miR-202-3p水平高于对照组(P<0.05)。miR-211-5p、miR-202-3p联合诊断抑郁症的AUC高于miR-211-5p(Z=4.701,P<0.001)、miR-202-3p(Z=2.275,P=0.023)单独诊断的AUC。与轻度抑郁组相比,中度抑郁组和重度抑郁组miR-211-5p水平依次降低,与轻度抑郁组相比,中度抑郁组和重度抑郁组miR-202-3p水平依次升高。不同认知功能抑郁症患者血清miR-211-5p水平比较:重度认知功能障碍组<中度认知功能障碍组<轻度认知功能障碍组;miR-202-3p水平比较:重度认知功能障碍组>中度认知功能障碍组>轻度认知功能障碍组(P<0.05)。Spearman相关性分析显示,抑郁症患者血清miR-211-5p水平与病情程度及认知功能损害呈负相关,miR-202-3p水平与病情程度及认知功能损害呈正相关(P<0.05)。结论抑郁症患者血清miR-211-5p低表达,miR-202-3p高表达,二者与病情程度及认知功能有关,有成为抑郁症辅助诊断生物学指标的潜力。 展开更多
关键词 微小核糖核酸-211-5p 微小核糖核酸-202-3p 抑郁症 病情程度 认知功能
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Future changes in precipitation and water availability over the Tibetan Plateau projected by CMIP6 models constrained by climate sensitivity 被引量:1
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作者 Hui Qiu Tianjun Zhou +3 位作者 Liwei Zou Jie Jiang Xiaolong Chen Shuai Hu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期40-46,共7页
Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assesse... Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assessed likely range of equilibrium climate sensitivity(ECS)and the climatological precipitation performance,the authors constrain the CMIP6(phase 6 of the Coupled Model Intercomparison Project)model projection of summer precipitation and water availability over the TP.The best estimates of precipitation changes are 0.24,0.25,and 0.45 mm d^(−1)(5.9%,6.1%,and 11.2%)under the Shared Socioeconomic Pathway(SSP)scenarios of SSP1–2.6,SSP2–4.5,and SSP5–8.5 from 2050–2099 relative to 1965–2014,respectively.The corresponding constrained projections of water availability measured by precipitation minus evaporation(P–E)are 0.10,0.09,and 0.22 mm d^(−1)(5.7%,4.9%,and 13.2%),respectively.The increase of precipitation and P–E projected by the high-ECS models,whose ECS values are higher than the upper limit of the likely range,are about 1.7 times larger than those estimated by constrained projections.Spatially,there is a larger increase in precipitation and P–E over the eastern TP,while the western part shows a relatively weak difference in precipitation and a drier trend in P–E.The wetter TP projected by the high-ECS models resulted from both an approximately 1.2–1.4 times stronger hydrological sensitivity and additional warming of 0.6℃–1.2℃ under all three scenarios during 2050–2099.This study emphasizes that selecting climate models with climate sensitivity within the likely range is crucial to reducing the uncertainty in the projection of TP precipitation and water availability changes. 展开更多
关键词 Tibetan plateau Climate sensitivity Precipitation projection Water availability projection
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Projecting Spring Consecutive Rainfall Events in the Three Gorges Reservoir Based on Triple-Nested Dynamical Downscaling 被引量:2
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作者 Yanxin ZHENG Shuanglin LI +2 位作者 Noel KEENLYSIDE Shengping HE Lingling SUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1539-1558,共20页
Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate model... Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate models(GCMs) are subject to considerable uncertainties, largely caused by their coarse resolution. This study applies a triple-nested WRF(Weather Research and Forecasting) model dynamical downscaling, driven by a GCM, MIROC6(Model for Interdisciplinary Research on Climate, version 6), to improve the historical simulation and reduce the uncertainties in the future projection of CREs in the TGR. Results indicate that WRF has better performances in reproducing the observed rainfall in terms of the daily probability distribution, monthly evolution and duration of rainfall events, demonstrating the ability of WRF in simulating CREs. Thus, the triple-nested WRF is applied to project the future changes of CREs under the middle-of-the-road and fossil-fueled development scenarios. It is indicated that light and moderate rainfall and the duration of continuous rainfall spells will decrease in the TGR, leading to a decrease in the frequency of CREs. Meanwhile, the duration, rainfall amount, and intensity of CREs is projected to regional increase in the central-west TGR. These results are inconsistent with the raw projection of MIROC6. Observational diagnosis implies that CREs are mainly contributed by the vertical moisture advection. Such a synoptic contribution is captured well by WRF, which is not the case in MIROC6,indicating larger uncertainties in the CREs projected by MIROC6. 展开更多
关键词 triple-nested downscaling Three Gorges Reservoir area consecutive rainfall events geological hazards projectION
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