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Research on the Implementation Strategies of Chemistry Science Popularization for Lower Grades in Primary Schools
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作者 Yaping He 《Journal of Contemporary Educational Research》 2025年第10期141-148,共8页
Chemistry science popularization for lower grades(Grades 1-2)in primary schools is an important part of science enlightenment education.However,in practice,it generally faces practical dilemmas such as insufficient co... Chemistry science popularization for lower grades(Grades 1-2)in primary schools is an important part of science enlightenment education.However,in practice,it generally faces practical dilemmas such as insufficient content adaptability,a single implementation method,and a lack of coordination mechanisms.Based on Piaget’s Cognitive Development Theory and the STSE(Science,Technology,Society,Environment)educational concept,this study constructed a four-in-one strategy system of“content development-teaching implementation-collaborative linkage-guarantee support”through literature analysis,action research,and empirical comparison.An empirical study was conducted in two primary schools for one academic year.The results show that this strategy system can increase students’interest in participating in chemistry science popularization by 42 percentage points,the compliance rate of observation ability reaches 85%,and the collaborative participation of families,schools,and society rises to 85%.The core strategies formed in the study,including“age-appropriate content screening,interactive teaching implementation,three-dimensional collaborative promotion,and full-process guarantee support,”provide a replicable practical model for the standardized and efficient development of chemistry science popularization for lower grades in primary schools.They also offer empirical references for fulfilling the requirement of“strengthening the pertinence and effectiveness of science popularization”in the Law of the People’s Republic of China on Popularization of Science and Technology(revised in 2024). 展开更多
关键词 Lower grades in primary schools Chemistry science popularization Implementation strategies Science enlightenment Collaborative education
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Interpretable model based on multisequence magnetic resonance imaging radiomics for predicting the pathological grades of hepatocellular carcinomas
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作者 Yue Shi Peng Zhang +4 位作者 Li Li Hui-Min Yang Zu-Mao Li Jing Zheng Lin Yang 《World Journal of Radiology》 2025年第12期42-55,共14页
BACKGROUND Despite the promising prospects of using artificial intelligence and machine learning(ML)for disease classification and prediction purposes,the complexity and lack of explainability of this method make it d... BACKGROUND Despite the promising prospects of using artificial intelligence and machine learning(ML)for disease classification and prediction purposes,the complexity and lack of explainability of this method make it difficult to apply the constructed models in clinical practice.We developed and validated an interpretable ML model based on magnetic resonance imaging(MRI)radiomics and clinical features for the preoperative prediction of the pathological grades of hepatocellular carcinomas(HCCs).This model will help clinicians better understand the situation and develop personalized treatment plans.AIM To develop and validate an interpretable ML model for preoperative pathological grade prediction in HCC patients via a combination of multisequence MRI radiomics and clinical features.METHODS MRI and clinical data derived from 125 patients with HCCs confirmed by postoperative pathological examinations were retrospectively analyzed.The patients were randomly split into training and validation groups(7:3 ratio).Univariate and multivariate logistic regression analyses were performed to identify independent clinical predictors.The tumor lesions observed on axial fatsuppressed T2-weighted imaging(FS-T2WI),arterial phase(AP),and portal venous phase(PVP)images were delineated in a slice-by-slice manner using 3D-slicer to generate volumetric regions of interest,and radiomic features were extracted.Interclass correlation coefficients were calculated,and least absolute selection and shrinkage operator regression were conducted for feature selection purposes.Six predictive models were subsequently developed for pathological grade prediction:FS-T2WI,AP,PVP,integrated radiomics,clinical,and combined radiomics-clinical(RC)models.The effectiveness of these models was assessed by calculating their area under the receiver operating characteristic curve(AUC)values.The clinical applicability of the models was evaluated via decision curve analysis.Finally,the contributions of the different features contained in the model with optimal performance were interpreted via a SHapley Additive exPlanations analysis.RESULTS Among the 125 patients,87 were assigned to the training group,and 38 were assigned to the validation group.The maximum tumor diameter,hepatitis B virus status,and monocyte count were identified as independent predictors of pathological grade.Twelve optimal radiomic features were ultimately selected.The AUC values obtained for the FS-T2WI model,AP model,PVP model,radiomics model,clinical model,and combined RC model in the training group were 0.761[95%confidence interval(CI):0.562-0.857],0.870(95%CI:0.714-0.918),0.868(95%CI:0.714-0.959),0.917(95%CI:0.857-0.959),0.869(95%CI:0.643-0.973),and 0.941(95%CI:0.857-0.945),respectively;in the validation group,the AUC values were 0.724(95%CI:0.625-0.833),0.802(95%CI:0.686-1.000),0.797(95%CI:0.688-1.000),0.901(95%CI:0.833-0.906),0.865(95%CI:0.594-1.000),and 0.932(95%CI:0.812-1.000),respectively.The combined RC model demonstrated the best performance.Additionally,the decision curve analysis revealed that the combined RC model had satisfactory prediction efficiency,and the SHapley Additive exPlanations value analysis revealed that the“FS-T2WI-wavelet-HLL_gldm_Large Dependence High Gray Level Emphasis”feature contributed the most to the model,exhibiting a positive effect.CONCLUSION An interpretable ML model based on MRI radiomics provides a noninvasive tool for predicting the pathological grade of HCCs,which will help clinicians develop personalized treatment plans. 展开更多
关键词 Machine learning SHapley Additive exPlanations algorithms Radiomic model Hepatocellular carcinoma Magnetic resonance imaging Pathological grading Inflammatory markers
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脑安滴丸(胶囊)治疗偏头痛临床应用专家共识
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作者 廖书琴 樊欢欢 +3 位作者 赖新星 郝同 曹克刚 高颖 《中华中医药学刊》 北大核心 2026年第2期253-258,共6页
脑安滴丸(胶囊)是医保乙类品种,其采用川芎、当归、人参、红花、冰片等原料提取制剂而成,具有活血化瘀、益气通络的功效。上市近20年以来脑安滴丸在临床得到广泛应用,可用于脑血栓引起的半身不遂、偏身麻木、语言不利、口舌歪斜及偏头... 脑安滴丸(胶囊)是医保乙类品种,其采用川芎、当归、人参、红花、冰片等原料提取制剂而成,具有活血化瘀、益气通络的功效。上市近20年以来脑安滴丸在临床得到广泛应用,可用于脑血栓引起的半身不遂、偏身麻木、语言不利、口舌歪斜及偏头痛引起的健忘、头晕、恶心、畏光、神疲乏力等属于气虚血瘀证者,但目前尚无基于循证证据制订的指南或共识来指导脑安滴丸(胶囊)的临床应用。在中华中医药学会的支持下,由北京中医药大学东直门医院牵头,联合国内其他24家单位编制该共识。通过系统梳理药品说明书及进行纳入全国110名临床医生的临床调研,通过名义组法确定需解决的临床问题。根据临床问题系统检索临床研究证据,采用GRADE系统进行证据体质量评价,最后通过名义组法对推荐意见/共识建议达成共识。该共识明确了脑安滴丸(胶囊)治疗偏头痛的用药特点、用药介入时机、用法用量、使用疗程、注意事项、禁忌证和不良反应及处理等,可促进该产品临床应用的规范性,提高临床疗效,减少用药风险。目前,该共识已通过中华中医药学会标准化办公室审查并发布,共识编号:GS/CACM 359-2024。 展开更多
关键词 偏头痛 脑安滴丸 脑安胶囊 专家共识 中成药 GRADE系统
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《实体器官移植霉酚酸治疗药物监测循证指南》解读
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作者 刘爽 宋再伟 +6 位作者 张相林 石炳毅 翟所迪 张伶俐 缪丽燕 侯小飞 赵荣生 《中国医院用药评价与分析》 2026年第2期129-132,144,共5页
《实体器官移植霉酚酸治疗药物监测循证指南》严格遵从临床实践指南的最新定义与世界卫生组织指南制订的方法学规范,在系统分析3.6万余篇研究证据的基础上,对霉酚酸(MPA)类药物的治疗药物监测(TDM)相关证据进行了循证评价和定性、定量整... 《实体器官移植霉酚酸治疗药物监测循证指南》严格遵从临床实践指南的最新定义与世界卫生组织指南制订的方法学规范,在系统分析3.6万余篇研究证据的基础上,对霉酚酸(MPA)类药物的治疗药物监测(TDM)相关证据进行了循证评价和定性、定量整合,采用国际规范的推荐意见分级的评价、制定与评估(GRADE)体系进行证据质量分级,并纳入140例患者意愿调查结果,经50名临床医药专家及患者代表的外部评审,共形成了4个部分16条推荐意见,涉及目标人群、监测指标、检测方法、剂量方案及浓度影响因素。该指南中文解读版旨在为实体器官移植受者接受MPA类药物治疗提供更为全面和详细的指导,从而促进MPA类药物TDM在临床实践中的规范化和标准化,提高移植受者的治疗效果和安全性。 展开更多
关键词 霉酚酸类药物 治疗药物监测 实体器官移植 循证指南 GRADE
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针灸治疗脑卒中后偏瘫的系统评价再评价
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作者 张家玮 姚远 +5 位作者 郭可盈 刘正 郭千喜 马俊杰 陈怡然 马铁明 《中医康复》 2026年第2期41-47,共7页
目的:对针灸治疗脑卒中后偏瘫的MAs/SRs(Meta-Analyses/Systematic Reviews)进行方法学质量和证据质量等级的综合评价。方法:对维普数据库(VIP)、中国知网(CNKI)、万方数据库(Wanfang)、中国生物医学文献服务系统(CBM)及PubMed、Cochran... 目的:对针灸治疗脑卒中后偏瘫的MAs/SRs(Meta-Analyses/Systematic Reviews)进行方法学质量和证据质量等级的综合评价。方法:对维普数据库(VIP)、中国知网(CNKI)、万方数据库(Wanfang)、中国生物医学文献服务系统(CBM)及PubMed、Cochrane Library、Web of Science数据库中收录的针灸治疗脑卒中后偏瘫的MAs/SRs进行检索,检索时限均为建库至2024年12月。方法学质量评估工具为AMSTAR 2,证据质量评估工具为GRADE系统。结果:本文纳入18篇MAs/SRs。根据AMSTAR 2量表评估,纳入的18篇MAs/SRs的方法学质量均为极低。根据GRADE系统评估,共纳入结局指标46个,其中高等质量1个,低质量5个,极低质量40个。结论:针灸作为一种传统疗法,在治疗脑卒中后偏瘫中取得了一定的疗效,但近年针灸治疗脑卒中后偏瘫的MAs/SRs质量偏低,未来需要更多的高水平的MAs/SRs对相关研究进行验证,临床应用需谨慎。 展开更多
关键词 脑卒中 偏瘫 针灸 系统评价再评价 AMSTAR2 GRADE
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中医药治疗冠状动脉临界病变的系统评价与Meta分析
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作者 王心意 田文得 +1 位作者 徐浩 陈可冀 《中国循证心血管医学杂志》 2026年第1期23-31,共9页
目的对中医药治疗冠状动脉临界病变的随机对照研究进行系统评价与Meta分析,评价中医药疗效与安全性,并评估现有研究的证据等级。方法计算机检索PubMed、Embase、Cochrane Library、Web of Science、中国知网、中国生物医学文献数据库、... 目的对中医药治疗冠状动脉临界病变的随机对照研究进行系统评价与Meta分析,评价中医药疗效与安全性,并评估现有研究的证据等级。方法计算机检索PubMed、Embase、Cochrane Library、Web of Science、中国知网、中国生物医学文献数据库、维普和万方数据库中医药治疗冠状动脉临界病变的随机对照研究,采用Cochrane 5.1.0偏倚风险评估工具进行方法学质量评价,运用RevMan 5.3软件进行Meta分析,运用GRADE(grading of recommendations,assessment,development and evaluation)系统对有统计学意义结局指标的证据质量进行评价。结果最终纳入文献18篇,涉及样本量1799例。结果显示,相较于单纯西医治疗,中西医结合治疗可显著改善中医证候有效率、心绞痛有效率、心电图有效率、西雅图心绞痛量表的各项评分,降低超敏C反应蛋白、白细胞介素-6等炎症因子水平,降低总胆固醇、甘油三酯、低密度脂蛋白胆固醇水平,提升高密度脂蛋白胆固醇水平,降低冠状动脉直径平均狭窄程度,减少平板运动阳性人数,提高左室射血分数,降低主要不良心脏事件发生率。GRADE证据等级评价提示,中医药改善冠状动脉临界病变患者心绞痛症状总有效率、中医证候总有效率、主要不良心脏事件、低密度脂蛋白胆固醇、西雅图心绞痛量表-躯体活动、左室射血分数为高质量证据,其余指标为极低质量、低质量或中等质量证据。结论中医药治疗冠状动脉临界病变具有一定优势,但在证据产出方面还存在较多局限,未来应尽快构建适合中医药临床试验的冠状动脉临界病变核心指标集,开展大样本随机对照研究,为该领域提供更多高质量循证医学证据。 展开更多
关键词 冠状动脉临界病变 中医药 系统评价 META分析 GRADE评价
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Annual Monitoring and Evaluation of the Grades of Arable Land Quality——Taking Lingchuan County as an Example 被引量:2
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作者 全坚 谭咪 《Agricultural Science & Technology》 CAS 2017年第6期1112-1119,共8页
With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and developm... With the increasing requirement for the protection of arable land, monitor- ing the grades of arable land quality is becoming more important, which can accu- rately and fully reflect the current situation and development trends of arable land quality. It is also an important measure for protecting the quality of arable land. in the present study, the distribution and changes of arable lands of different gradient types and grades in Lingchuan County, Guangxi Zhuang Autonomous Region in 2015 were monitored and evaluated, to analyze the trends and reasons for the changes in the quality and productivity of arable lands, and to provide references for dynamic monitoring of the quality of arable land. 展开更多
关键词 Arable land grades MONITORING Evaluation Lingchuan County
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培土生金中药联合西医常规疗法治疗支气管哮喘缓解期肺脾两虚证的Meta分析及GRADE质量评价
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作者 余荣祥 宋德胤 《江西中医药》 2026年第1期45-49,共5页
目的:系统评价培土生金中药联合西医常规疗法治疗支气管哮喘缓解期肺脾两虚证的疗效以及证据质量,为临床决策及疾病指南制订提供循证依据。方法:检索中国知网(CNKI)、万方数据库(Wangfang)、Pubmed、Web of Science等8大中英文数据库,由... 目的:系统评价培土生金中药联合西医常规疗法治疗支气管哮喘缓解期肺脾两虚证的疗效以及证据质量,为临床决策及疾病指南制订提供循证依据。方法:检索中国知网(CNKI)、万方数据库(Wangfang)、Pubmed、Web of Science等8大中英文数据库,由2名研究者独立进行文献筛选、信息提取、偏倚风险评估及方法学质量评价,并对纳入研究的总有效率、中医证候积分、第一秒用力呼气容积(FEV1)、第一秒用力呼气容积/用力肺活量(FEV1/FVC)、哮喘控制测试(ACT)评分等结局指标进行Meta分析,最终依照GRADE评估证据质量。结果:共纳入14项研究,合计1263例患者。结果显示:(1)培土生金中药联合常规西医疗法可有效改善患者总有效率,降低患者中医证候积分,改善患者FEV1水平、FEV1/FVC及ACT评分。(2)总有效率证据质量较优,可信度高,其余指标证据质量较低,尚待更多高质量的研究支持以提升证据级别。结论:培土生金中药联合西医常规疗法治疗支气管哮喘缓解期肺脾两虚证优于单用西医常规治疗,且在总有效率上证据质量较高,具有一定的循证学意义。 展开更多
关键词 支气管哮喘 缓解期 肺脾两虚证 培土生金 中药 META分析 GRADE评价
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血必净注射液治疗脓毒症的系统评价再评价
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作者 姜晓薇 杨继 刘毅 《药学前沿》 2026年第2期311-321,共11页
目的对血必净注射液治疗脓毒症的系统评价/Meta分析进行再评价,综合评价其方法学质量、报告质量及证据质量,为临床实践和指南制定提供循证依据。方法检索中英文数据库,包括中国知网(CNKI)、万方、维普(VIP)、中国生物医学文献服务系统(S... 目的对血必净注射液治疗脓毒症的系统评价/Meta分析进行再评价,综合评价其方法学质量、报告质量及证据质量,为临床实践和指南制定提供循证依据。方法检索中英文数据库,包括中国知网(CNKI)、万方、维普(VIP)、中国生物医学文献服务系统(SinoMed)、PubMed、Embase、Cochrane Library及Web of Science(WOS),纳入截至2025年10月20日发表的血必净注射液治疗脓毒症的系统评价/Meta分析。采用AMSTAR 2量表评价方法学质量,PRISMA 2020核对单评价报告质量,并结合GRADE系统进行证据分级。结果共纳入16篇系统评价/Meta分析,发表时间为2010—2023年。主要结局指标包括病死率、急性生理与慢性健康评分(APACHEⅡ)、炎症因子及凝血指标。AMSTAR 2结果显示,方法学质量总体为低级至极低级,关键缺陷集中在注册方案缺失(条目2)。PRISMA 2020结果显示,报告完整度均值为57.41%,其他结果分析、注册和协议、利益冲突等条目缺失率>50%。GRADE评估结果表明,病死率、APACHEⅡ评分及安全性证据为中等质量。结论血必净注射液联合常规治疗可降低脓毒症病死率、改善器官功能及炎症反应,且安全性较好。但现有证据质量有限,尚需高质量、多中心随机对照试验与规范系统评价进一步验证。 展开更多
关键词 血必净注射液 脓毒症 系统评价再评价 AMSTAR 2 PRISMA 2020 GRADE 证据质量 随机对照试验
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Additive Manufacturing of Functionally Graded Lattice Structures for Personalized Below-Knee Prosthetic Dampers
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作者 Guy O'Keefe Naser A.Alsaleh +3 位作者 Mahmoud A.El-Sayed A.Jiménez Sabbah Ataya Khamis Essa 《Chinese Journal of Polymer Science》 2026年第1期173-188,I0014,共17页
Functionally graded cellular structures(FGCSs)have a multitude of applications to a wide range of industries.Utilising the ever-progressing technology of additive manufacturing(AM),FGCSs can be applied to control mate... Functionally graded cellular structures(FGCSs)have a multitude of applications to a wide range of industries.Utilising the ever-progressing technology of additive manufacturing(AM),FGCSs can be applied to control material grading and achieve the desired mechanical properties.The current study explores the design and optimisation of FGCSs for AM,with a focus on improving the compression and impact performance of below knee(BK)prosthetic limbs made of thermoplastic polyurethane(TPU).A multiscale research methodology integrating topology optimization(TO),finite element analysis(FEA),and design of experiments(Do E)was adopted to optimise lattice structures in terms of stiffness and lightweight properties.Two-unit cell designs were considered in the study:Schwarz P gyroid and body-centered cubic(BCC).Response surface methodology(RSM)was implemented to analyse the effect of minimum and maximum cell wall thickness,cell size,and unit cell type on the mechanical performance of TPU FGCS structures.The results indicated that a Schwarz P FGCS structure with cell size,minimum and maximum cell wall thickness of 6,0.9 and 2.8 mm,respectively,could be optimal for a compromise between performance and weight.In this optimized case,stiffness and volume fraction values of 684 N/mm and 0.64 were obtained,respectively.The study also presents a proof-of-concept design for a BK prosthetic damper,highlighting the potential of FGCSs to enhance patient comfort,reduce manufacturing costs,and enable personalised designs through 3D scanning and AM.The obtained results could be a step forward towards the incorporation of AM technologies in prosthetics,offering a pathway to lightweight,cost-effective,and functionally tailored solutions. 展开更多
关键词 Additive manufacturing Functionally graded cellular structures Topology optimization PROSTHETICS
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A Cooperative Hybrid Learning Framework for Automated Dandruff Severity Grading
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作者 Sin-Ye Jhong Hui-Che Hsu +3 位作者 Hsin-Hua Huang Chih-Hsien Hsia Yulius Harjoseputro Yung-Yao Chen 《Computers, Materials & Continua》 2026年第4期2272-2285,共14页
Automated grading of dandruff severity is a clinically significant but challenging task due to the inherent ordinal nature of severity levels and the high prevalence of label noise from subjective expert annotations.S... Automated grading of dandruff severity is a clinically significant but challenging task due to the inherent ordinal nature of severity levels and the high prevalence of label noise from subjective expert annotations.Standard classification methods fail to address these dual challenges,limiting their real-world performance.In this paper,a novel,three-phase training framework is proposed that learns a robust ordinal classifier directly from noisy labels.The approach synergistically combines a rank-based ordinal regression backbone with a cooperative,semi-supervised learning strategy to dynamically partition the data into clean and noisy subsets.A hybrid training objective is then employed,applying a supervised ordinal loss to the clean set.The noisy set is simultaneously trained using a dualobjective that combines a semi-supervised ordinal loss with a parallel,label-agnostic contrastive loss.This design allows themodel to learn fromthe entire noisy subset while using contrastive learning to mitigate the risk of error propagation frompotentially corrupt supervision.Extensive experiments on a new,large-scale,multi-site clinical dataset validate our approach.Themethod achieves state-of-the-art performance with 80.71%accuracy and a 76.86%F1-score,significantly outperforming existing approaches,including a 2.26%improvement over the strongest baseline method.This work provides not only a robust solution for a practical medical imaging problem but also a generalizable framework for other tasks plagued by noisy ordinal labels. 展开更多
关键词 Dandruff severity grading ordinal regression noisy label learning self-supervised learning contrastive learning medical image analysis
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The steady-state dynamic contact of a viscoelastic FGM-coated half-plane under a rigid flat punch
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作者 Xiaomin WANG Liaoliang KE +1 位作者 Jie SU Junhong GUO 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期61-76,共16页
This study explores the dynamic contact response of a viscoelastic functionally graded material(FGM)-coated half-plane under a rigid flat punch subjected to a time-harmonic vertical force.The elastic modulus and mass ... This study explores the dynamic contact response of a viscoelastic functionally graded material(FGM)-coated half-plane under a rigid flat punch subjected to a time-harmonic vertical force.The elastic modulus and mass density of the FGM coating vary exponentially along the thickness direction.The FGM coating and the homogeneous half-plane possess viscoelastic properties,which are described by a linearly hysteretic damping model.By applying the asymptotic method and the Fourier integral transform technique,the contact problem is converted into a Cauchy singular integral equation.The effects of excitation frequency,gradient index,damping factor ratio,and punch width on the vertical impedance and dynamic contact stress are analyzed.The results indicate that adjusting the gradient index of the FGM coating can significantly affect the contact stress and vertical impedance. 展开更多
关键词 dynamic contact functionally graded material(FGM)coating hysteretic damping flat punch
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High-performance thermomagnetic generation in low-grade waste heat recovery
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作者 Haodong Chen Hu Zhang +4 位作者 Mingze Liu Kaiming Qiao Lichen Wang Fengxia Hu Baogen Shen 《Chinese Physics B》 2026年第2期25-41,共17页
Thermomagnetic generation(TMG),a heat-to-electricity conversion technology based on the thermomagnetic effect,offers high reliability and broad adaptability to diverse heat sources.By exploiting the temperature-depend... Thermomagnetic generation(TMG),a heat-to-electricity conversion technology based on the thermomagnetic effect,offers high reliability and broad adaptability to diverse heat sources.By exploiting the temperature-dependent magnetization of thermomagnetic materials,TMG converts thermal energy into electrical energy through cyclic changes in magnetic flux based on Faraday's law.The performance of TMG systems is largely governed by the intrinsic properties of the working materials and the design of device architecture.Ideal TMG materials exhibit sharp and reversible magnetization transitions near the operating temperature,low thermal hysteresis,and high thermal conductivity.Device configurations can be broadly categorized into active and passive systems:active TMG devices rely on controlled thermal cycling and optimized magnetic circuits for enhanced output,whereas passive devices utilize self-actuated mechanical motion to generate electricity.In this topical review,we provide a comprehensive overview of recent advances in TMG materials and device configurations.Furthermore,we discuss future development trends and offer perspectives on experimental strategies to advance this field. 展开更多
关键词 low grade waste heat thermal energy recovery thermomagnetic generation
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Moderately large amplitude forced vibration of sandwich functionally graded auxetic beams:an analytical approach
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作者 F.M.NASREKANI H.EIPAKCHI 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期99-114,共16页
Sandwich functionally graded(FG)auxetic beams are extensively utilized in aerospace,automotive,and biomedical industries due to their excellent strength-toweight ratio,impact resistance,and tunable mechanical properti... Sandwich functionally graded(FG)auxetic beams are extensively utilized in aerospace,automotive,and biomedical industries due to their excellent strength-toweight ratio,impact resistance,and tunable mechanical properties.The integration of FG materials with auxetic structures enhances their adaptability in advanced engineering applications.However,understanding their dynamic behavior under external excitations is essential for optimal design and structural reliability.Nonlinear interactions in such structures pose significant challenges in vibration analysis,necessitating robust analytical methods.This study presents a closed-form solution for the nonlinear forced vibration analysis of sandwich FG auxetic beams,offering an accurate and efficient method for predicting their dynamic response.The beam consists of two FG face sheets with material properties varying through the thickness and a re-entrant honeycomb auxetic core with an adjustable Poisson's ratio.The governing nonlinear equations of motion are derived using the first-order shear deformation theory(FSDT),the modified Gibson model,and the von Kármán relations,formulated through Hamilton's principle.A closed-form solution is obtained via the Galerkin method and multiple-scale technique.The results demonstrate that FG layers enable control of the overweight and dynamic response amplitude,with positive power law indexes reducing weight.Comparisons with finite element results confirm the accuracy of the proposed formulation. 展开更多
关键词 functionally graded(FG)auxetic beam nonlinear forced vibration closedform solution multiple-scale method first-order shear deformation theory(FSDT)
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Characterization and comparison of the aroma-active compounds on different grades of sesame-flavor Baijiu by headspace solid-phase microextraction and gas chromatography-olfactometry-mass spectrometry 被引量:17
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作者 Dan Qin Jiawen Duan +4 位作者 Hehe Li Fuping Zheng Huan Cheng Xingqian Ye Baoguo Sun 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期79-88,共10页
This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfact... This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction(HS-SPME)coupled with gas chromatography-olfactometry-mass spectrometry(GC-O-MS).A total of 54 aroma-active compounds were detected.Principal component analysis showed that JZ1,JZ2,and JZ3 were well separated from each other.JZ1 as the premium-grade Baijiu had the highest aroma intensities,concentrations.According to aroma intensities and concentrations,dimethyl trisulfide,butanoic acid,phenylacetaldehyde,2-furylmethanethiol,ethyl hexanoate,2,6-dimethylpyrazine,etc.could be potentially applied as volatile makers to distinguish the three different grades of sesame-flavor Baijiu as their significant difference(P<0.05)in three Baijiu samples.Roasted aroma had the significant difference(P<0.05)in three sample base on aroma profiles.Meanwhile,2-furylmethanethiol,2,6-dimethylpyrazine were related to the roasted aroma,they may be had a significant contribution to the differences of three different grades of sesame-flavor Baijiu.This study has provided a comprehensive understanding of the differences of three different grades of sesame-flavor Baijiu. 展开更多
关键词 Sesame-flavor Baijiu Baijiu grades Sensory evaluation Principal component analysis 2-Furylmethanethiol
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Trends in the Different Grades of Precipitation over South China during 1960–2010 and the Possible Link with Anthropogenic Aerosols 被引量:10
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作者 FU Chuanbo DAN Li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第2期480-491,共12页
Using observed daily precipitation data to classify five levels of rainy days by strength in South China (SC),with an emphasis on the Pearl River Delta (PRD) region,the spatiotemporal variation of different grades... Using observed daily precipitation data to classify five levels of rainy days by strength in South China (SC),with an emphasis on the Pearl River Delta (PRD) region,the spatiotemporal variation of different grades of precipitation during the period 1960-2010 was analyzed and the possible link with anthropogenic aerosols examined.Statistical analysis showed that drizzle and small precipitation has significantly decreased,whereas medium to heavy precipitation has increased slightly over the past 50 years (although not statistically significant).Further data analysis suggested that the decline in drizzle and small precipitation probably has a strong link to increased concentrations of anthropogenic aerosols produced by large-scale human activities related to the rapid socioeconomic development of the PRD region.These aerosols may also have led to the obvious decreasing trend in horizontal visibility and sunshine duration in SC,which is statistically significant according to the t-test. 展开更多
关键词 precipitation grades rainy days horizontal visibility sunshine duration anthropogenic aerosols
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Tumor regression grades:Potential outcome predictor of locally advanced rectal adenocarcinoma after preoperative radiotherapy 被引量:8
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作者 Yi-Fan Peng Wei-Dong Yu +5 位作者 Hong-Da Pan Lin Wang Ming Li Yun-Feng Yao Jun Zhao Jin Gu 《World Journal of Gastroenterology》 SCIE CAS 2015年第6期1851-1856,共6页
AIM:To analyze tumor regression grade(TRG)for prognosis of locally advanced rectal adenocarcinoma(LARA)treated with preoperative radiotherapy.METHODS:One hundred and ninety patients with clinical stageⅡ/ⅢLARA were s... AIM:To analyze tumor regression grade(TRG)for prognosis of locally advanced rectal adenocarcinoma(LARA)treated with preoperative radiotherapy.METHODS:One hundred and ninety patients with clinical stageⅡ/ⅢLARA were studied.All patients underwent radical surgery(between 2004 and 2010)after 30-Gy/10-fraction preoperative radiotherapy(preRT).All 190 patients received a short course of preRT and were reassessed for disease recurrence and survival;the slides of surgical specimens were reviewed and classified according to Mandard TRG.We compared patients with good response(Mandard TRG1 or TRG2)vs patients with bad/poor response(Mandard TRG3-5).Outcomes evaluated were 5-year overall survival(OS),5-year disease-free survival(DFS),and local,distant and mixed recurrence.Fisher’s exact test orχ2 test,logrank test and proportional hazards regression analysis were used to calculate the probability that Mandard TRG was associated with patient outcomes.RESULTS:One hundred and sixty-six of 190 patients(87.4%)were identified as Mandard bad responders(TRG3-5).High Mandard grade was correlated with tumor height(41.7%<6 cm vs 58.3%≥6 cm,P=0.050),yp T stage(75%yp T0-2 vs 25%yp T3-4,P=0.000),and yp N stage(75%yp N0 vs 25%yp N1,P=0.031).In univariate survival analysis,Mandard grade bad responders had significantly worse OS and DFSthan good responders(TRG1/2)(OS,83.1%vs 96.4%,P=0.000;DFS,72.3%vs 92.0%,P=0.002).In multivariate survival analysis,Mandard bad responders had significantly worse DFS than Mandard good responders(DFS 3.8 years(95%CI:1.2-12.2 years,P=0.026).CONCLUSION:Mandard grade good responders had a favorable prognosis.TRG may be a potential predictor for DFS in LARA after pre-RT. 展开更多
关键词 TUMOR regression GRADE PREOPERATIVE RADIOTHERAPY R
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Effects of PM2.5 Exposure in Different Air Quality Grades on Daily Outpatient Visits for Childhood Asthma in Shijiazhuang, China 被引量:8
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作者 FU Gui Qin JIANG Yan Feng +4 位作者 LIU Lan Ping LIU Hua Yue ZHOU Ji CUI Xiao Wei WANG Shi Gong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第12期888-892,共5页
Asthma is a common chronic inflammatory disorder that is more prevalent in children than in adults.China has seen an increasing prevalence of childhood asthma in recentdecades[1].Earlier studies have shown that air pa... Asthma is a common chronic inflammatory disorder that is more prevalent in children than in adults.China has seen an increasing prevalence of childhood asthma in recentdecades[1].Earlier studies have shown that air particulate matter (PM),particularly fine particulate matter(PM2.5)[2],is an important factor triggering childhood asthma. Since nationalPM2.5data were nota vailabl euntil 2013, 展开更多
关键词 Effects of PM China Exposure in Different Air Quality grades on Daily Outpatient Visits for Childhood Asthma in Shijiazhuang
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Aluminum potassium sulfate and tannic acid sclerotherapy for Goligher GradesⅡandⅢhemorrhoids:Results from a multicenter study 被引量:11
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作者 Hidenori Miyamoto Takenori Hada +2 位作者 Gentaro Ishiyama Yoshito Ono Hideo Watanabe 《World Journal of Hepatology》 CAS 2016年第20期844-849,共6页
AIM:To show that aluminum potassium sulfate and tannic acid(ALTA)sclerotherapy has a high success rate for GradeⅡandⅢhemorrhoids.METHODS:This study was based on the clinical data of 604 patients with hemorrhoids who... AIM:To show that aluminum potassium sulfate and tannic acid(ALTA)sclerotherapy has a high success rate for GradeⅡandⅢhemorrhoids.METHODS:This study was based on the clinical data of 604 patients with hemorrhoids who underwent ALTA sclerotherapy between January 2009 and February 2015.The objective of this study was to assess the efficacy of this treatment for GradesⅡandⅢhemorrhoids.Preoperative and postoperative symptoms,complications and success rate were all assessed retrospectively.Follow-up consisted of a simple questionnaire,physical examination and an anoscopy.Patients were followed-up at one day,one week,two weeks,one month,one year,two years,three years,four years and five years after the ALTA sclerotherapy.RESULTS:One hundred and sixty-nine patients were diagnosed with GradeⅡhemorrhoids and 435 patients were diagnosed with GradeⅢhemorrhoids.The one year,three year and five year cumulative success rates of ALTA sclerotherapy for GradesⅡandⅢhemo-rrhoids were 95.9%and 93.1%;89.3%and 83.7%;and 89.3%and 78.2%,respectively.No significant differences were observed in the cumulative success rates after ALTA sclerotherapy between GradesⅡandⅢhemorrhoids(P=0.09).There were forty-seven post-operative complications(low grade fever;anal pain;urinary retention;rectal ulcer;and others).No serious or life-threatening complications occurred and all cases improved through conservative treatment.At univariate analysis there were no predictive factors of failure.CONCLUSION:ALTA sclerotherapy has had a high success rate for GradeⅡandⅢhemorrhoids during five years of post-operative treatment.However,additional studies are needed to evaluate the efficacy of this ALTA sclerotherapy in the management of hemorrhoidal disease. 展开更多
关键词 SCLEROTHERAPY Aluminum potassium sulfate and tannic acid Goligher gradeⅢ Minimally invasive treatment HEMORRHOID
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Essential competencies for three grades of midwives in China 被引量:5
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作者 Yazhen Yin Jie Li +2 位作者 Hong Lu Jiasi Yao Rui Hou 《International Journal of Nursing Sciences》 2018年第1期18-23,共6页
Objective:To identify the essential competencies for different grades of midwives in China.Methods:A nationwide modified Delphi process was implemented to amend and screen the indicators.Thirty expert panellists inclu... Objective:To identify the essential competencies for different grades of midwives in China.Methods:A nationwide modified Delphi process was implemented to amend and screen the indicators.Thirty expert panellists including practitioners (nurse-midwives),clinical managers,academic educators and obstetricians completed a two-round Delphi study through an electronic survey that was supplemented by an expert panel meeting for discussion of comments and suggestions.Results:All panellists completed two rounds of Delphi study and at least 75% of them achieved a consensus on 224 items (W1 =0.150,W2 =0.173).Seven domains were established,namely,'Professional quality','Antenatal care','Intrapartum care','Postnatal care','Neonatal care','Gynaecological care','Public health care & Integrative competency'.Generalised maternal and neonatal knowledge and perinatal care skills were set for'junior'midwives,pathological care for'senior'ones and supervisory abilities and promotion of discipline for'expert'ones.Conclusions:This research developed three grades of essential competencies for midwives in China.The next step will be assessment in clinical settings for further response.The set was in line with the concepts of International Confederation of Midwives under the domestic context.This set could be adopted as a reference in developing normalised midwifery practice,education and certification. 展开更多
关键词 ESSENTIAL COMPETENCY GRADE MIDWIVES
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