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Study on superoxide and hydroxyl radicals generated in indirect electrochemical oxidation by chemiluminescence and UV-Visible spectra 被引量:3
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作者 ZHANG, Bo-Tao ZHAO, Li-Xia LIN, Jin-Ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期1006-1011,共6页
The generation and transformation of radicals on the cathode of indirect electrochemical oxidation were studied by chemilumines- cence(CL)and UV-Visible spectra in the reactor with a salt bridge that connected the sep... The generation and transformation of radicals on the cathode of indirect electrochemical oxidation were studied by chemilumines- cence(CL)and UV-Visible spectra in the reactor with a salt bridge that connected the separated chambers.The CL intensity of 4×10^(-9)mol/L luminol on the cathode with bubbling oxygen was about seven times that of the intensity without it,which was because of the generation of reactive oxygen species(ROS).The existence of ROS,especially the generation of the superoxide radical,coul... 展开更多
关键词 chemiluminescence(CL) uv-visible RADICAL indirect electrochemical oxidation
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Inflammatory Bowel Disease and Dementia:Evidence Triangulation from a Meta-Analysis of Observational Studies and Mendelian Randomization Study
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作者 Di Liu Meiling Cao +9 位作者 Shanshan Wu Bingli Li Yiwen Jiang Tengfei Lin Fuxiao Li Weijie Cao Jinqiu Yuan Feng Sha Zhirong Yang Jinling Tang 《Biomedical and Environmental Sciences》 2025年第1期56-66,共11页
Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsist... Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsistent.It remains unclear whether these associations are causal.Methods We conducted a meta-analysis by systematically searching for observational studies on the association between IBD and dementia.Mendelian randomization(MR)analysis based on summary genome-wide association studies(GWASs)was performed.Genetic correlation and Bayesian colocalization analyses were used to provide robust genetic evidence.Results Ten observational studies involving 80,565,688 participants were included in this metaanalysis.IBD was significantly associated with dementia(risk ratio[RR]=1.36,95%CI=1.04-1.78;I2=84.8%)and VD(RR=2.60,95%CI=1.18-5.70;only one study),but not with AD(RR=2.00,95%CI=0.96-4.13;I^(2)=99.8%).MR analyses did not supported significant causal associations of IBD with dementia(dementia:odds ratio[OR]=1.01,95%CI=0.98-1.03;AD:OR=0.98,95%CI=0.95-1.01;VD:OR=1.02,95%CI=0.97-1.07).In addition,genetic correlation and co-localization analyses did not reveal any genetic associations between IBD and dementia.Conclusion Our study did not provide genetic evidence for a causal association between IBD and dementia risk.The increased risk of dementia observed in observational studies may be attributed to unobserved confounding factors or detection bias. 展开更多
关键词 DEMENTIA Inflammatory bowel disease META-ANALYSIS Observational studies Mendelian randomization Genetic evidence Evidence triangulation
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Research on the Training Model of“Foreign Languages+Area Studies”Interdisciplinary Talent Development:A Case Study of China’s Talent Training for International Ocean Affairs
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作者 GUO Rui 《Sino-US English Teaching》 2025年第1期22-27,共6页
This paper proposes an interdisciplinary talent training model that combines foreign language education with area studies.The model aims to cultivate international ocean affairs professionals with cross-cultural commu... This paper proposes an interdisciplinary talent training model that combines foreign language education with area studies.The model aims to cultivate international ocean affairs professionals with cross-cultural communication skills,in-depth regional and country knowledge,and practical expertise in ocean affairs.Additionally,the paper presents specific training pathways and policy recommendations for implementing this model. 展开更多
关键词 foreign languages area studies talent development for international ocean affairs educational reform
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Study on English Translations of“The Little Prince”from the Perspective of Descriptive Translation Studies
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作者 Xianting Yi 《Journal of Contemporary Educational Research》 2025年第9期358-365,共8页
In modern society,the globalization of literary works is evident,with exceptional literary pieces from various countries spreading worldwide.Among these,children’s literature,due to the specificity of its target audi... In modern society,the globalization of literary works is evident,with exceptional literary pieces from various countries spreading worldwide.Among these,children’s literature,due to the specificity of its target audience,imposes distinct requirements on children’s books,compelling translators to approach the text from a child’s perspective.“The Little Prince”has renowned both within and outside of China,and a careful reading of this work can provide us with much inspiration.To this end,the present study adopts the perspective of Gideon Toury’s Descriptive Translation Studies to conduct an in-depth analysis of the different English and Chinese translations in conjunction with the original French novel.This approach aims to better guide literary research and explores translation methods for children’s literature through the analysis of translation norms and rules. 展开更多
关键词 Gideon toury Descriptive translation studies “The Little Prince” Children’s literature
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Root cause analysis from the perspectives of patients in primary care units:cases study of typical adverse drug events
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作者 Ping Gong Xing-Yang Chen +1 位作者 Qin Long Ting-Ting Zhou 《Frontiers of Nursing》 2026年第1期61-68,共8页
Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth... Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth interviews with patients and families,anchored by Interactive Patient Par ticipation Theory,to analyze 4 high-severity adverse drug events(ADE)cases.Cases were purposively sampled from 8 communities in China's National Adverse Event Monitor Center(2018-2023).Semi-structured interviews explored patient perspectives,with data analyzed via thematic coding and triangulation against clinical records.Results:Five interconnected themes emerged:(1)erosion of trust,(2)communication breakdowns,(3)information asymmetry,(4)environmental inadequacies,and(5)technological alienation.Notably,75% of participants had≤high school education,and 50% used≥7 medications daily,compounding ADE risks.Conclusions:We considered elements mentioned by theory,exploring trust,communication,information,and suppor t as the root causes.In addition,we added“adaptability to new technology”as an impor tant and necessary component.It is impor tant and necessary to analyze typical adverse drug events from the perspectives of patients. 展开更多
关键词 adverse drug events case study medication safety patients safety primary care units root cause analysis qualitative study THEORY
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Geographical differentiation of riverine DOM composition and source apportionment:A case study of a riverine network of a mountainous stream,a Plain River,and an artificial canal
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作者 Jun-wei Zhao Shuang-bing Huang +2 位作者 Zhao-xin Su Wei-Chao Huang Yong Qian 《Journal of Groundwater Science and Engineering》 2026年第1期59-68,共10页
To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river ... To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river types within Shandong Province:The mountainous Dawen River,the plain Tuhai River,and the artificial East Grand Canal.The DOM composition was analyzed using Ultraviolet-Visible(UV-Vis)absorption spectroscopy,Excitation-Emission Matrix(EEM)fluorescence spectroscopy,and parallel factor analysis(PARAFAC),while Principal Component Analysis(PCA)was employed to quantify the synergistic effects of natural processes and anthropogenic activities.Results revealed significant spatial heterogeneity in DOM composition and sources.The plain river exhibited the highest aromaticity(humic-like components:43.3%)due to long-term agricultural non-point source inputs and urban wastewater discharge.The mountain stream,shaped by complex terrain and relatively intact ecosystems,was dominated by autochthonous DOM derived from microbial metabolism,with higher Fluorescence Index(FI=2.12)and biological index(BIX=1.35)than other river types.The artificial canal retained protein-like components(64.2%),largely attributed to winter hydrological stagnation and disturbances from shipping activities.Further analysis demonstrated that geographical settings(e.g.,mountain terrain)and anthropogenic activities(e.g.,agriculture,shipping)jointly regulated DOM composition by altering the balance between input and transformation processes.Integrated fluorescence parameters and PCA results suggested differentiated management strategies:protecting ecological integrity in mountain streams to sustain selfpurification,enhancing non-point source interception in plain rivers,and mitigating shipping pollution in canals.This study systematically reveals the natural-anthropogenic coupling mechanisms driving DOM dynamics in northern China rivers,providing critical insights for precision water environment management at the watershed scale. 展开更多
关键词 Dissolved organic matter(DOM) uv-vis spectroscopy Parallel factor analysis(PARAFAC) Geographical settings Anthropogenic activities
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How does mindfulness influence study engagement?The role of affect and psychological capital pathways in university students
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作者 Xiang Deng Zaida Nor binti Zainudin +1 位作者 Xiaoling Wang Wan Norhayati Wan Othman 《Journal of Psychology in Africa》 2026年第1期9-20,共12页
Mindfulness would enhance university students’emotional well-being and study engagement.However,the role of affect(positive and negative emotions)and psychological resources(psychological capital)linking mindfulness ... Mindfulness would enhance university students’emotional well-being and study engagement.However,the role of affect(positive and negative emotions)and psychological resources(psychological capital)linking mindfulness to study engagement remain underexplored.This cross-sectional study surveyed 688 Chinese university students(females=413,mean age=20.3,SD=0.83),using validated self-report measures of mindfulness,positive and negative emotions,psychological capital,and study engagement.Structural equation modeling and bias-corrected bootstrap analyses(5000 resamples)revealed that mindfulness directly enhanced positive emotions,psychological capital,and study engagement,while reducing negative emotions.Positive emotions partially mediated the positive effect of mindfulness on psychological capital and study engagement.Negative emotions partially and negatively mediated only the mindfulness-psychological capital link.Psychological capital independently mediated the mindfulness-engagement relationship,and two sequential mediation pathways emerged:(a)mindfulness→positive emotions→psychological capital→higher study engagement and(b)mindfulness→reduced negative emotions→psychological capital→higher study engagement.Consistent with broaden-and-build(B&B)theory and Conservation of Resources(COR)theory,these findings suggest that mindfulness fosters study engagement primarily by promoting positive emotional experiences and strengthening psychological capital.By implication,university student support programs should employ mindfulness-based interventions to cultivate emotional and psychological resources for higher students’engagement and overall well-being. 展开更多
关键词 MINDFULNESS positive emotions negative emotions psychological capital study engagement
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Ethical awareness and issues in gastrointestinal endoscopy practice:A survey study
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作者 Yi Qin Ming-Yang Shi 《World Journal of Gastroenterology》 2026年第1期151-157,共7页
BACKGROUND Gastrointestinal endoscopy technology has significantly improved the diagnostic accuracy and the successful treatment of gastrointestinal diseases.However,a series of ethical issues have emerged,such as exp... BACKGROUND Gastrointestinal endoscopy technology has significantly improved the diagnostic accuracy and the successful treatment of gastrointestinal diseases.However,a series of ethical issues have emerged,such as expanding treatment indications,which affect the fair distribution of medical resources.There is limited research on ethical issues in the field of digestive endoscopy.AIM To investigate the level of ethical awareness among gastrointestinal endoscopy practitioners and analyze the ethical issues involved in gastrointestinal endoscopy technology.METHODS A questionnaire survey was performed to collect relevant data(gender,age,degree of education,professional title,personnel category,the level of understanding medical ethical principles,ethics training and its learning pathways)from gastrointestinal endoscopy practitioners at the Second Hospital of Dalian Medical University and Dalian Friendship Hospital,including licensed physicians and nurses(including trainees and graduate students).RESULTS The majority of gastrointestinal endoscopy practitioners have received training on ethics,but there is still considerable room for improvement in their ethical awareness.Different learning pathways may affect the mastery of ethical principles, and understanding of ethical principles is more easily achieved through hospital ethics institutions.CONCLUSIONTo address the ethical issues in gastrointestinal endoscopy technology, it is necessary to enhance the humanisticeducation of gastrointestinal endoscopy practitioners, incorporate ethical standards into the technology assessmentprocess, and establish a patient-centered diagnostic and treatment model to improve the ethical awareness of practitionersand achieve a balance between technology and ethics. 展开更多
关键词 Gastrointestinal endoscopy Ethical awareness Ethical issues Medical ethics Survey study
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In situ Studies of Electrochemical Energy Conversion and Storage Technologies:From Materials,Intermediates,and Products to Surroundings
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作者 Xing Chen Yu-Lin Sun +2 位作者 Xiu-Mei Lin Jin-Chao Dong Jian-Feng Li 《Nano-Micro Letters》 2026年第5期746-797,共52页
Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance ... Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance relies on elucidating reaction mechanisms and structure-performance relationships via in situ studies.This review summarizes recent in situ studies of EECSTs through a variety of advanced characterization techniques aiming at mapping reaction pathways for the rational design of overall high-performance reaction systems.We outline the principles,capabilities,advantages,and limitations of various in situ techniques.Their applications in in situ studies of fuel cells,water/CO_(2)electrolysis,and lithium batteries are highlighted with representative examples.These studies enable dynamic tracking of chemical and structural evolution of overall reaction systems,including materials,intermediates,products,and surroundings during operation,providing insights critical to rational system design.Future advancements will involve integrating multimodal in situ/operando approaches with artificial intelligence to enable real-time monitoring at practical scales.Such integration promises precise mechanistic insights and robust structure-performance correlations,ultimately accelerating the development of high-performance EECSTs aligned with sustainability and market requirements. 展开更多
关键词 In situ studies ELECTROCATALYSIS Lithium batteries Reaction mechanisms Structure-performance relationships
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Mechanisms and Heterogeneous Effects of Physical Activity on Mental Health:Evidence from the China Family Panel Studies
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作者 Chun-Chieh Hu Shuhan Zheng Youjia Lin 《International Journal of Mental Health Promotion》 2026年第2期83-111,共29页
Objectives:In recent years,mental health has emerged as a pressing public health concern in China,driven by mounting societal pressures and fast-paced urban lifestyles.Physical activity,a well-established means of enh... Objectives:In recent years,mental health has emerged as a pressing public health concern in China,driven by mounting societal pressures and fast-paced urban lifestyles.Physical activity,a well-established means of enhancing psychological well-being,has received growing scholarly and policy attention.This study uses panel data from the 2020 and 2022 waves of the China Family Panel Studies(CFPS)to examine the impact of exercise frequency on mental health(with indicators such as CESD-8 depression scores)among college students and young employees,thereby providing empirical support for targeted mental health interventions.Methods:This study examines the relationship between individual exercise frequency and mental health among college students and young employees,using panel data from the 2020 and 2022 waves of the China Family Panel Studies(CFPS),with the Chinese version of the 8-item Center for Epidemiologic Studies Depression Scale(CESD-8)depression scores,self-rated health,and life satisfaction as outcome variables.Specifically,this study tests three hypotheses:(H1)increased exercise frequency significantly reduces depression symptoms and enhances well-being;(H2)the effects of exercise vary by social roles,with stronger mental health benefits among employed individuals and those with lower education;and(H3)lifestyle factors such as smoking amount,sleep duration,and Body Mass Index(BMI)partially mediate the relationship between exercise and mental health.Employing a two-way fixed effects model,baseline results indicate that a one-unit increase in exercise frequency significantly reduces the CESD-8 score by 0.183 points.To address potential endogeneity and spurious regression concerns,an instrumental variable(IV)approach is further applied.The heterogeneity analysis differentiates between students and employed individuals.Results:Among students,the effects of exercise on mental health are not statistically significant,regardless of education level.In contrast,for the employed,exercise demonstrates a significant positive impact on mental health,with particularly pronounced effects among those with lower educational attainment.These findings underscore the importance of promoting exercise as part of comprehensive mental health strategies.Mediation analysis indicates that the beneficial effect of exercise on mental health is partially transmitted through reductions in adverse health behaviors,especially smoking.Conclusions:Policymakers should integrate physical activity promotion into health interventions,prioritizing vulnerable groups to enhance psychological resilience and foster inclusive,health-oriented development. 展开更多
关键词 Mental health EXERCISE China family panel studies educational level SMOKING
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Causal relationships between 41 inflammatory cytokines and myopia:a Mendelian randomization study
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作者 Xiao-Fei Wu Lei Yu +3 位作者 Ying Zhang Shuang Li Rui Li Lian-Yi Sun 《International Journal of Ophthalmology(English edition)》 2026年第3期575-581,共7页
AIM:To investigate the potential causal associations between 41 inflammatory cytokines and myopia using a two-sample Mendelian randomization(MR)approach.METHODS:Publicly available genome-wide association study(GWAS)da... AIM:To investigate the potential causal associations between 41 inflammatory cytokines and myopia using a two-sample Mendelian randomization(MR)approach.METHODS:Publicly available genome-wide association study(GWAS)datasets were utilized for this two-sample MR analysis.Inflammatory cytokine-related GWAS data were extracted from The University of Bristol’s Research Data Repository,and myopia-related GWAS data were obtained from the FinnGen project.Single nucleotide polymorphisms(SNPs)associated with inflammatory cytokines were systematically selected as instrumental variables(IVs)based on three rigorous criteria:relevance,independence,and exclusion of pleiotropy.Five MR methods were employed for causal inference:the inverse-variance weighted(IVW)method as the primary analysis,supplemented by MREgger regression,weighted median estimator,simple mode,and weighted mode approaches.Sensitivity analyses were performed to evaluate the robustness of the causal estimates.RESULTS:A total of 773 myopia-associated SNPs were identified.MR analysis revealed that higher levels of macrophage inflammatory protein 1-α(MIP-1α)were associated with a 17%reduced risk of myopia[odds ratio(OR)=0.83;95%confidence interval(CI):0.69-0.99;P<0.05].In contrast,elevated levels of eotaxin(OR=1.26;95%CI:1.07-1.47;P<0.01),stromal cell-derived factor-1α(SDF-1α;OR=1.68;95%CI:1.08-2.62;P<0.05),and interleukin-2 receptor subunit alpha(IL-2Rα;OR=1.25;95%CI:1.01-1.53;P<0.05)were significantly associated with an increased risk of myopia.Sensitivity analyses confirmed the reliability of these results.CONCLUSION:This study provides evidence supporting a causal relationship between specific inflammatory cytokines and myopia.MIP-1αmay act as a protective factor against myopia,while eotaxin,SDF-1α,and IL-2Rαare potential risk factors for myopia.These findings emphasize the critical role of inflammatory pathways in the pathogenesis of myopia,offering novel insights for the development of preventive and therapeutic strategies for myopia. 展开更多
关键词 MYOPIA inflammatory cytokines Mendelian randomization causal association single nucleotide polymorphism genome-wide association study
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Profiling vaccine attitudes and subsequent uptake in 1·1 million people in England:a nationwide cohort study
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作者 Matthew Whitaker 《四川生理科学杂志》 2026年第1期216-216,共1页
Background:Despite highly effective vaccines against SARS-CoV-2,COVID-19 vaccine hesitancy persisted in some populations in England during the pandemic,with rates and motivations for hesitancy varying by demographic g... Background:Despite highly effective vaccines against SARS-CoV-2,COVID-19 vaccine hesitancy persisted in some populations in England during the pandemic,with rates and motivations for hesitancy varying by demographic group.Addressing the drivers of vaccine hesitancy through targeted interventions in hesitant groups is a public health priority for better and more rapid control of disease spread.We aimed to characterise the determinants and subtypes of vaccine hesitancy and identify more persistent forms of hesitancy via analysis of vaccine uptake in a large cross-sectional cohort with linked National Health Service(NHS)data. 展开更多
关键词 vaccine hesitancy demographic group targeted interventions vaccine uptake vaccine attitudes SARS CoV public health priority nationwide cohort study
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Early GLP-1 Agonist Use and Cancer Risk in Type 2 Diabetes:A Real-World Data Cohort Study
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作者 Cheng-Hsun Chuang Ping-Kun Tsai +2 位作者 Shih-Wen Kao Yu-Hsun Wang Chao-Bin Yeh 《Oncology Research》 2026年第1期237-253,共17页
Background:To determine whether initiating a glucagon-like peptide-1 receptor agonist(GLP-1 RA)within 3 months of type 2 diabetes(T2DM)diagnosis alters the subsequent risk of overall and site-specific cancer and wheth... Background:To determine whether initiating a glucagon-like peptide-1 receptor agonist(GLP-1 RA)within 3 months of type 2 diabetes(T2DM)diagnosis alters the subsequent risk of overall and site-specific cancer and whether this association differs by baseline body-mass index(BMI).Methods:This retrospective cohort study used electronic health records from the TriNetX U.S.research network.Adults aged 20 years or older diagnosed with T2DM between 2016 and 2024 were included if they received any hypoglycemic agents within 3 months before and after diagnosis.Following 1:1 propensity score matching,both the GLP-1 RA user and non-user groups included 183,264 patients.The study outcome was defined as a diagnosis of malignant neoplasms.Hazard ratios(HRs)for overall and site-specific cancer risk were estimated using Cox proportional hazards models.Kaplan–Meier analysis and stratified analysis by BMI were performed.Results:Early GLP-1 RA use demonstrated a modest but significant association with reduced overall cancer risk(HR 0.93;95%CI:0.90–0.96).Reduced risks were noted for cancers of the digestive(HR 0.81),respiratory(HR 0.66),and female genital(HR 0.87)systems.In stratified analysis,benefits were more pronounced in patients with BMI≥30,particularly for pancreatic and colorectal cancers.Conclusion:Early initiation of GLP-1 receptor agonists in patients with diagnosed T2DM was associated with a modest reduction in overall cancer risk,particularly among individuals with obesity.These findings highlight the dual metabolic and oncologic value of prompt GLP-1 RA therapy. 展开更多
关键词 Glucagon-like peptide-1(GLP-1)receptor agonists type 2 diabetes mellitus cancer risk OBESITY cohort study
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Comparative Studies on Tourist Satisfaction of World Heritage Sites——A Case Study of Huangshan Mountain,Lushan Mountain and Wuyi Mountain
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作者 顾晓艳 《Journal of Landscape Research》 2009年第4期85-90,共6页
Through the questionnaire survey and comparative studies on tourist satisfaction of tourism services among three world heritage sites,i.e.Huangshan Mountain,Lushan Mountain and Wuyi Mountain,this study pointed out the... Through the questionnaire survey and comparative studies on tourist satisfaction of tourism services among three world heritage sites,i.e.Huangshan Mountain,Lushan Mountain and Wuyi Mountain,this study pointed out the problems in tourism services of three scenic areas and then put forward relevant countermeasures for the management of scenic areas. 展开更多
关键词 World HERITAGE SITES TOURIST SATISFACTION COMPARATIVE study Huangshan MOUNTAIN Lushan MOUNTAIN Wuyi MOUNTAIN
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Characterization on the Exfoliation Degree of Graphite Oxide into Graphene Oxide by UV-visible Spectroscopy 被引量:3
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作者 艾凡荣 ZHONG Yu +1 位作者 HU Xiaowu YAN Xiluan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第3期515-518,共4页
The exfoliation degree of graphite oxide into graphene oxide plays an important role in the massive production method of reduced graphene oxide. It is significant to find a simple and feasible method to analyze the ex... The exfoliation degree of graphite oxide into graphene oxide plays an important role in the massive production method of reduced graphene oxide. It is significant to find a simple and feasible method to analyze the exfoliation degree of graphite oxide. In the present work, graphite oxide was synthesized by a modified Hummers method, and then graphene oxide colloids were obtained by exfoliation of graphite oxide dispersed in de-ionized water. UV-visible spectroscopy was used to characterize the absorption of the graphene oxide colloids, and the concentration of graphene oxide colloids indicated by absorption area of UV-visible spectra was studied. Results show that there is a relatively stable relationship between them, indicating that UV- visible spectroscopy is a potential method for analyzing the exfoliation degree of graphite oxide into graphene oxide. 展开更多
关键词 GRAPHENE graphene oxide graphene oxide colloids uv-visible spectroscopy
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Pressure-flow studies in patients with benign prostatic hyperplasia:a study comparing suprapubic and transurethral methods 被引量:2
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作者 Shan-Chao Zhao Shao-Bin Zheng Wan-Long Tan Peng Zhang Huan Qi 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第6期731-735,共5页
Aim: To compare the use of the suprapubic puncture method versus the transurethral method in pressure-flow studies in patients with benign prostatic hyperplasia. Methods: Twenty-three men with benign prostatic hyper... Aim: To compare the use of the suprapubic puncture method versus the transurethral method in pressure-flow studies in patients with benign prostatic hyperplasia. Methods: Twenty-three men with benign prostatic hyperplasia underwent both suprapubic and transurethral pressure-flow studies during a single session. Standard pressure-flow variables were recorded in all patients with both methods, enabling calculation of obstruction using commonly used grading systems, such as the urethral resistance algorithm, the Abrams-Griffith (AG) number and the Schaefer linear nomogram. Results: There were statistically significant differences between the methods in the mean values of maximum flow rate (P 〈 0.05), detrusor pressure at the maximum flow (P 〈 0.01), urethral resistance algorithm (P 〈 0.01), AG number (P 〈 0.01) and maximum cystic capacity (P 〈 0.01). Of the men in the study, 10 (43.5%) remained in the same Schaefer class with both methods and 18 (78.3%) in the same AG number area. Using the transurethral method, 12 (52.2%) men increased their Schaefer class by one and 1 (4.3%) by two. There were also differences between the suprapubic and transurethral methods using the AG number: 4 (17.4%) men moved from a classification of equivocal to obstructed and 1 (4.3%) from unobstructed to equivocal. Conclusion: The differences between the techniques for measuring intravesical pressure alter the grading of obstruction determined by several of the commonly used classifications. An 8 F transurethral catheter significantly increases the likelihood of a diagnosis of bladder outlet obstruction when compared with the suprapubic method. 展开更多
关键词 URODYNAMICS pressure-flow study SUPRAPUBIC TRANSURETHRAL benign prostatic hyperplasia bladder outlet obstruction
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Sensitivity Enhancement in Uranium Determination by UV-Visible Spectroscopy Using Ion Imprinted Polymer 被引量:2
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作者 Tulin BICIM Mehmet YAMAN 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第6期1992-1997,共6页
There is need to determination of uranium concentration at ppb level in environmental matrices.Due to low sensitivity of FAAS,UV-Visible Spectroscopy is generally used as measurement technique.In this study,ion-imprin... There is need to determination of uranium concentration at ppb level in environmental matrices.Due to low sensitivity of FAAS,UV-Visible Spectroscopy is generally used as measurement technique.In this study,ion-imprinted polymers(IIP)were prepared for uranyl ion(imprint ion)by formation of ternary(salicylaldoxime and 4-vinylpyridine)complex in 2-methoxy ethanol(porogen)following copolymerization with methacrylic acid(MAA)as a functional monomer and ethylene glycol dimethacrylate(EGDMA)as crosslinking monomer using 2,2-azobisisobutyronitrile as initiator.The synthesized polymers were characterized by FTIR and TGA analysis.ArsenazoⅢin 3M HClO_4 was used as complexing agent in the measurement step.The optimal pH for preconcentration was found to be between 3.5~6.5values.The developed method was applied to uranium(Ⅵ)determination in natural water samples. 展开更多
关键词 URANIUM Ion imprinted polymer ArsenazoⅢ uv-vis Spectroscopy
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Contacted Ion Pairs in Aqueous CuCl2 by the Combination of Ratio Spectra, Difference Spectra, Second Order Difference Spectra in the UV-Visible Spectra
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作者 鞠思文 张宁 +4 位作者 王志强 张睿挺 曾德文 邵晓鹏 林珂 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第6期657-663,I0001,I0002,共9页
The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the... The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the UV-visible spectra of thin fihn of CuCl2/H2O solutions at different concentrations. This method is the combination of ratio spectra, difference spectra and second order difference spectra. By using this method, two new bands at -230 and -380 nm are obviously observed. The bands are assigned as the contacted ion pairs [CuCl3(H2O)n]- or [CuCl4(H2O)n]2-, which demonstrates that ion pairs exist in the CuCl2/H2O solution. Such finding agrees with the recent theoretical spectra obtained by time-dependent density functional theory. Furthermore, the populations of the contacted ion pairs are discussed. This study not only offers the direct spectroscopic evidence of [CuCl3(H2O)n]- or [CuCl4(H2O)n]2- in aqueous CuCl2, but also suggests that the spec- troscopic analysis method is powerful to extract the weak bands in a strong overlapping spectrum. 展开更多
关键词 uv-visible spectroscopy Ratio spectra Difference spectra CuCl2/H2O solution Ion pair
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UV-Vis Spectroscopy Study on Interaction between Microperoxidase-11 and Pr Ion Under Acid Rain Stress 被引量:2
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作者 吉红念 黄晓华 +1 位作者 周青 陆天虹 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期541-546,共6页
Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the ... Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm. 展开更多
关键词 rare earths PRASEODYMIUM MICROPEROXIDASE-11 uv-vis spectroscopy acid rain stress antagonistic effect
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