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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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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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Residential greenness,air pollution,and incident age-related macular degeneration:A prospective cohort study
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作者 Jiali Wang Yinyan Gao +2 位作者 Yijuan Lin Irene X.Y.Wu Fang Xiao 《Journal of Environmental Sciences》 2026年第1期242-249,共8页
Existing evidence suggests residential greenness is beneficial to human,while no research to date explored the associations of greenness with age-related macular degeneration(AMD).To evaluate the association of greenn... Existing evidence suggests residential greenness is beneficial to human,while no research to date explored the associations of greenness with age-related macular degeneration(AMD).To evaluate the association of greenness with AMD,modification and mediation effect of air pollution,we conducted this prospective study.We con-structed weighted quantile sum(WQS)index as co-exposure to nitrogen oxides(NO_(x)),particulate matter<2.5μm(PM_(2.5)),particulate matter<10μm(PM10).Stratified Cox regression models were applied to test the effect of exposure.Effect modification of air pollution was assessed.Stratified Cox models through the indirect method and Aalen additive risk models were used in mediation analysis.Over median follow-up of 11.67 years,4596 AMD events were ascertained.Hazard ratios(HRs)and 95%confidence intervals(95%CIs)of incident AMD for pollution per interquartile range(IQR)increment were 1.10(1.04–1.16)for nitrogen dioxide(NO_(2)),1.09(1.03–1.15)for NO_(x),1.14(1.05–1.24)for PM_(2.5),1.13(1.05–1.21)for PM10.The HR(95%CI)of AMD associated with greenness 1000 m buffer per IQR increment was 0.91(0.86–0.97),300 m buffer was 0.94(0.89–0.99).The as-sociation between greenness 1000 m and AMD was 28.59%,44.77%,35.59%,32.31%and 27.08%mediated by the decreased WQS index,NO_(2),NO_(x),PM_(2.5) and PM10,respectively.Increased greenness was associated with lower AMD incidence,and air pollution partly mediate it,which implies that interventions aimed at improving air quality and increasing greenness could have a dual benefit in mitigating AMD risk. 展开更多
关键词 Age-related macular degeneration(AMD) Residential greenness Ambient air pollution Mediation effect Prospective cohort 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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Multi-wave amplitude-preserved AVO modeling considering wave propagation effects
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作者 侯波 陈小宏 +1 位作者 李景叶 张孝珍 《Applied Geophysics》 SCIE CSCD 2011年第3期207-216,240,共11页
Traditional AVO forward modeling only considers the impact of reflection coefficients at the interface on seismic wave field amplitude and ignores various propagation effects. Introducing wave propagation effects incl... Traditional AVO forward modeling only considers the impact of reflection coefficients at the interface on seismic wave field amplitude and ignores various propagation effects. Introducing wave propagation effects including geometric spreading, transmission loss, attenuation into seismic wave propagation, multi-wave amplitude-preserved AVO forward modeling for horizontally layered media based on ray theory is proposed in this paper. We derived the multi-wave geometric spreading correction formulas for horizontally layered media in order to describe the geometric spreading effect of multi-wave propagation. Introducing the complex traveltime directly, we built the relationship between complex traveltime and quality factor without the help of complex velocity to describe the attenuation of viscoelastic media. Multi-wave transmission coefficients, obtained by solving the Zoeppritz equations directly, is used to describe the transmission loss. Numerical results show that the effects of geometric spreading, attenuation, and transmission loss on multi-wave amplitude varies with offset and multi-wave amplitude-preserved AVO forward modeling should consider the reconstructive effect of wave propagation on reflection amplitude. 展开更多
关键词 Amplitude-preserved AVO geometric spreading attenuation transmission loss complex traveltime multi-wave
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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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Reservoir prediction using multi-wave seismic attributes 被引量:2
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作者 Ye Yuan Yang Liu +2 位作者 Jingyu Zhang Xiucheng Wei Tiansheng Chen 《Earthquake Science》 CSCD 2011年第4期373-389,共17页
The main problems in seismic attribute technology are the redundancy of data and the uncertainty of attributes, and these problems become much more serious in multi-wave seismic exploration. Data redundancy will incre... The main problems in seismic attribute technology are the redundancy of data and the uncertainty of attributes, and these problems become much more serious in multi-wave seismic exploration. Data redundancy will increase the burden on interpreters, occupy large computer memory, take much more computing time, conceal the effective information, and especially cause the "curse of dimension". Uncertainty of attributes will reduce the accuracy of rebuilding the relationship between attributes and geological significance. In order to solve these problems, we study methods of principal component analysis (PCA), independent component analysis (ICA) for attribute optimization and support vector machine (SVM) for reservoir prediction. We propose a flow chart of multi-wave seismic attribute process and further apply it to multi-wave seismic reservoir prediction. The processing results of real seismic data demonstrate that reservoir prediction based on combination of PP- and PS-wave attributes, compared with that based on traditional PP-wave attributes, can improve the prediction accuracy. 展开更多
关键词 seismic attribute multi-wave exploration independent component analysis supportvector machine reservoir prediction
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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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Monitoring the change in horizontal stress with multi-wave time-lapse seismic response based on nonlinear elasticity theory 被引量:2
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作者 Fu-Bin Chen Zhao-Yun Zong Xing-Yao Yin 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期815-826,共12页
Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (... Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (CO_(2)) injection and storage, shallow surface prospecting and deep-earth structure description. The change in in-situ stress induced by hydrocarbon production and localized tectonic movements causes the changes in rock mechanic properties (e.g. wave velocities, density and anisotropy) and further causes the changes in seismic amplitudes, phases and travel times. In this study, the nonlinear elasticity theory that regards the rock skeleton (solid phase) and pore fluid as an effective whole is used to characterize the effect of horizontal principal stress on rock overall elastic properties and the stress-dependent anisotropy parameters are therefore formulated. Then the approximate P-wave, SV-wave and SH-wave angle-dependent reflection coefficient equations for the horizontal-stress-induced anisotropic media are proposed. It is shown that, on the different reflectors, the stress-induced relative changes in reflectivities (i.e., relative difference) of elastic parameters (i.e., P- and S-wave velocities and density) are much less than the changes in contrasts of anisotropy parameters. Therefore, the effects of stress change on the reflectivities of three elastic parameters are reasonably neglected to further propose an AVO inversion approach incorporating P-, SH- and SV-wave information to estimate the change in horizontal principal stress from the corresponding time-lapse seismic data. Compared with the existing methods, our method eliminates the need for man-made rock-physical or fitting parameters, providing more stable predictive power. 1D test illustrates that the estimated result from time-lapse P-wave reflection data shows the most reasonable agreement with the real model, while the estimated result from SH-wave reflection data shows the largest bias. 2D test illustrates the feasibility of the proposed inversion method for estimating the change in horizontal stress from P-wave time-lapse seismic data. 展开更多
关键词 Monitoring change in horizontal stress multi-wave reflection coefficients Nonlinear elasticity theory Time-lapse seismic data
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STABILITY OF STEADY MULTI-WAVE CONFIGURATIONS FOR THE FULL EULER EQUATIONS OF COMPRESSIBLE FLUID FLOW 被引量:2
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作者 Gui-Qiang G.CHEN Matthew RIGBY 《Acta Mathematica Scientia》 SCIE CSCD 2018年第5期1485-1514,共30页
We are concerned with the stability of steady multi-wave configurations for the full Euler equations of compressible fluid flow. In this paper, we focus on the stability of steady four-wave configurations that are the... We are concerned with the stability of steady multi-wave configurations for the full Euler equations of compressible fluid flow. In this paper, we focus on the stability of steady four-wave configurations that are the solutions of the Riemann problem in the flow direction, consisting of two shocks, one vortex sheet, and one entropy wave, which is one of the core multi-wave configurations for the two-dimensional Euler equations. It is proved that such steady four-wave configurations in supersonic flow are stable in structure globally, even under the BV perturbation of the incoming flow in the flow direction. In order to achieve this, we first formulate the problem as the Cauchy problem (initial value problem) in the flow direction, and then develop a modified Glimm difference scheme and identify a Glimm-type functional to obtain the required BV estimates by tracing the interactions not only between the strong shocks and weak waves, but also between the strong vortex sheet/entropy wave and weak waves. The key feature of the Euler equations is that the reflection coefficient is always less than 1, when a weak wave of different family interacts with the strong vortex sheet/entropy wave or the shock wave, which is crucial to guarantee that the Glimm functional is decreasing. Then these estimates are employed to establish the convergence of the approximate solutions to a global entropy solution, close to the background solution of steady four-wave configuration. 展开更多
关键词 STABILITY multi-wave configuration vortex sheet entropy wave shock wave BV perturbation full Euler equations steady wave interactions Glimm scheme
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Coffee consumption and risk of type 2 diabetes mellitus in Asians:A meta-epidemiological study of population-based cohort studies 被引量:1
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作者 Jong-Myon Bae 《World Journal of Diabetes》 SCIE 2021年第6期908-915,共8页
BACKGROUND Previous systematic reviews have consistently reported that coffee consumption has a preventive effect on the occurrence of type 2 diabetes mellitus(T2DM).However,further evaluations between coffee consumpt... BACKGROUND Previous systematic reviews have consistently reported that coffee consumption has a preventive effect on the occurrence of type 2 diabetes mellitus(T2DM).However,further evaluations between coffee consumption and the risk of T2DM in Asian populations are needed.AIM To conduct a meta-epidemiological study on systematic reviews evaluating the association between coffee consumption and the risk of T2DM in Asian people.METHODS The selection criterion was defined as a population-based prospective cohort study evaluating the association between coffee consumption and the risk of T2DM in Asian populations,reporting the adjusted relative risk(RR)and its 95%confidence interval(CI)for potential confounders.A fixed-effect model metaanalysis was applied to calculate the summary RR and its 95%CI in less than 50%of the I2 value indicating the level of heterogeneity.A two-stage fixed-effects doseresponse meta-analysis(DRMA)was performed to calculate the risk per unit dose(a cup per day).RESULTS A total of seven studies were selected in this meta-epidemiological study.The risk of T2DM in Asian populations was significantly reduced in the highest to the lowest dose group(summary RR=0.73,95%CI:0.66-0.82;I2 value=0.0%).The DRMA showed that drinking one cup of coffee per day reduced the risk of T2DM in Asian populations by 8%(RR=0.92,95%CI:0.90-0.95).CONCLUSION These findings support the conclusion that coffee consumption has a protective effect on the occurrence of T2DM in Asian men and women. 展开更多
关键词 COFFEE Diabetes mellitus Cohort studies META-ANALYSIS Systematic reviews
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A Comparative Study of Of Studies and Wang Zuoliang's Translated Version
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作者 陈健飞 《海外英语》 2014年第21期139-140,152,共3页
Of Studies is an important one in The Essays of Francis Bacon, of which words are concise and refining, reasoning is profound and logic. Wang Zuoliang's translated version is so efficient and smooth with classical... Of Studies is an important one in The Essays of Francis Bacon, of which words are concise and refining, reasoning is profound and logic. Wang Zuoliang's translated version is so efficient and smooth with classical Chinese style that it perfectly reveals the original text, turning out to be the best version among all the translation of Of Studies. This thesis compares Of Studies and Wang Zuoliang's translated version to analyze their linguistic feature in terms of diction, sentence and figures of speech. 展开更多
关键词 Of Studies translated VERSION DICTION SENTENCE FIG
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An ultrasonic multi-wave focusing and imaging method for linear phased arrays
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作者 Yu-Xiang Dai Shou-Guo Yan Bi-Xing Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期303-310,共8页
To overcome the inherent limits of traditional single wave imaging for nondestructive testing,the multi-wave focusing and imaging method is thoroughly studied.This method makes the compressional waves and shear waves ... To overcome the inherent limits of traditional single wave imaging for nondestructive testing,the multi-wave focusing and imaging method is thoroughly studied.This method makes the compressional waves and shear waves focused in both emission and reception processes,which strengthens the focusing energy and improves the signal-to-noise ratio of received signals.A numerical model is developed to study the characteristics of a multi-wave focusing field.It is shown that the element width approaching 0.8 wavelengths of shear waves can keep a balance between the radiation energy of two waves,which can achieve a desirable multi-wave focusing performance.And an experiment using different imaging methods for a linear phased array is performed.It can be concluded that due to the combination of the propagation and reflection characteristics of two waves,the multi-wave focusing and imaging method can significantly improve the imaging distinguishability of defects and expand the available sweeping range to a sector of-650 to 65°. 展开更多
关键词 multi-wave focusing ultrasonic imaging phased array non-destructive testing
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Optical Multi-wave Mixing Process Based on Electromagnetically InducedTransparency
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作者 LIJia-Hua PENGJu-Cun CHENAi-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期106-110,共5页
In this paper, we propose and analyze an optical multi-wave mixing scheme for the generation of coherent light in a five-level atomic system in the context of electromagnetically induced transparency. A detailed semic... In this paper, we propose and analyze an optical multi-wave mixing scheme for the generation of coherent light in a five-level atomic system in the context of electromagnetically induced transparency. A detailed semiclassical study of the propagation of generated mixing and probe fields is demonstrated. The analytical dependence of the generated mixing field on the probe field and the respective detuning is predicted. Such a nonlinear optical process can be used for generating short-wavelength radiation at low pump intensities. 展开更多
关键词 optical multi-wave mixing electromagnetically induced transparency Rabi frequency
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Dressed multi-wave mixing in a V-type four-level atomic system
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作者 姜彤 张彦鹏 +8 位作者 聂志强 李岭 李沛哲 沈磊剑 傅鑫 甘琛利 赵荣阔 宋建平 卢克清 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2984-2992,共9页
The dressed four- and six-wave mixings in a V-type four-level system are considered. Under two different dressed conditions, two- and three-photon resonant Autler-Townes splittings, accompanied by enhancement and supp... The dressed four- and six-wave mixings in a V-type four-level system are considered. Under two different dressed conditions, two- and three-photon resonant Autler-Townes splittings, accompanied by enhancement and suppression of wave mixing signal, are obtained analytically. Meanwhile, an electromagnetic induced transparency of multi-wave mixing is presented, which shows multiple peaks and asymmetric effects caused by one-photon, two-photon and three-photon resonances, separately. The slow light propagation multiple region of multi-wave mixing signal is also obtained. 展开更多
关键词 Autler-Townes splitting electromagnetic induced transparency multi-wave mixing
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Study design in evidence-based surgery:What is the role of case-control studies?
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作者 Amy M Cao Michael R Cox Guy D Eslick 《World Journal of Methodology》 2016年第1期101-104,共4页
Randomized controlled trials(RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become... Randomized controlled trials(RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become the major study design used in surgical research when RCTs are unable to be conducted and definitely replacing case series which offer little insight into surgical outcomes and disease processes. 展开更多
关键词 Research STUDIES CASE-CONTROL STUDIES RANDOMIZED CLINICAL trials BIAS SAMPLE size
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