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Comparison of bronchoalveolar lavage recovery across patient positions:a retrospective study
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作者 Yiting Wang Xinglai Sun 《Science International Innovative Medicine》 2025年第1期37-42,共6页
Objective To compare the effect of patient positioning on bronchoscopy-guided bronchoalveolar lavage(BAL)recovery rate and to inform position selection in clinical practice.Methods A retrospective study was conducted ... Objective To compare the effect of patient positioning on bronchoscopy-guided bronchoalveolar lavage(BAL)recovery rate and to inform position selection in clinical practice.Methods A retrospective study was conducted using routine BAL records from 2019 to 2024 at a single center.Four position groups were analyzed(n=110 each):supine,lateral nondependent(target lung up),lateral dependent(target lung down),and prone.The primary outcome was recovery rate(%).Distributional assumptions were evaluated with the Shapiro-Wilk test and Levene's test.Group differences were assessed by one-way analysis of variance(ANOVA);pairwise post-hoc comparisons used Welch's t test with mean differences and 95%confidence intervals(CI).A linear regression model adjusted for lobar site was used to estimate lobe-adjusted marginal means by position.Results Mean(x±SD)recovery rates were:supine 52.08±7.70%,lateral nondependent 62.66±8.27%,lateral dependent 45.98±8.50%,prone 55.12±7.59%.Between-group differences were significant(ANOVA F=82.14,P<0.001).Lobe-adjusted marginal means were directionally consistent with unadjusted results.Conclusions Patient position is significantly associated with BAL recovery.When clinically feasible and safe,placing the target lung in the nondependent position yields higher recovery rates. 展开更多
关键词 BRONCHOSCOPY bronchoalveolar lavage patient positioning recovery rate retrospective study
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Comparisons of various insulin resistance indices for new-onset metabolic syndrome before midlife:The CHIEF cohort study,2014-2020
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作者 Wei-Nung Liu Yi-Chiung Hsu +4 位作者 Yen-Po Lin Kun-Zhe Tsai Yen-Chen Lin Pang-Yen Liu Gen-Min Lin 《World Journal of Diabetes》 2025年第5期192-201,共10页
BACKGROUND Some non-insulin-based insulin resistance(IR)indices have been found to be associated with metabolic syndrome(MetS);however,few cohort studies have compared the capacities of these indices for predicting in... BACKGROUND Some non-insulin-based insulin resistance(IR)indices have been found to be associated with metabolic syndrome(MetS);however,few cohort studies have compared the capacities of these indices for predicting incident MetS in young adults.AIM To investigate the associations of various non-insulin-based IR(NI-IR)indices with new-onset MetS in young military personnel.METHODS A total of 2890 armed forces personnel in Taiwan who were aged 18-39 years and did not have MetS at baseline were followed to monitor the incidence of new-onset MetS from 2014 to the end of 2020.Six NI-IR indices,including the metabolic score for IR(METS-IR),triglyceride(TG)-to-high-density lipoprotein cholesterol(HDL-C)ratio,TG glucose(TyG)index,Zhejiang University(ZJU)index,total cholesterol(TC)-to-HDL-C ratio,and alanine transaminase(ALT)-to-aspartate transaminase(AST)ratio,were defined according to specific criteria.Incident MetS was identified on the basis of each annual health examination using the International Diabetes Federation criteria.Multiple Cox regression analyses were conducted,adjusting for age,sex,waist circumference,smoking status,alcohol consumption status,and physical activity,to assess the associations of the NI-IR indices with incident MetS.The area under the receiver operating characteristic curve(AUROC)was used to compare the capacities of these NI-IR indices for predicting new-onset MetS.RESULTS During a median follow-up of 5.8 years,there were 673 patients with new-onset MetS(23%).All six of the NI-IR indices were significantly and positively associated with incident MetS.In the entire cohort,the greatest AUROC was found for the METS-IR[0.782;95%confidence interval(CI):0.762-0.801;all P values compared to the other NIIR indices<0.05],followed by the TG/HDL-C ratio(0.752;95%CI:0.731-0.772),ZJU index(0.743;95%CI:0.722-0.764),TyG index(0.734;95%CI:0.713-0.756),TC/HDL-C ratio(0.731;95%CI:0.709-0.752),and then the ALT/AST ratio(0.734;95%CI:0.713-0.756).CONCLUSION This study suggests that almost all the NI-IR indices are associated with the development of MetS in military young adults.The METS-IR is the strongest predictor of new-onset MetS before midlife. 展开更多
关键词 Cohort study Insulin resistance indices Metabolic syndrome Young adults
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Examining emotional intelligence of hospital-based nursing students with comparison between full-time and part-time study modes:A cross-sectional study
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作者 Joanna Hiu Ki Ko Daniel Yee Tak Fong 《Nursing Communications》 2025年第17期1-6,共6页
association with academic and clinical performance.This study aimed to determine the EI level of hospital-based nursing students and examine differences between full-time and part-time students.Methods:We conducted a ... association with academic and clinical performance.This study aimed to determine the EI level of hospital-based nursing students and examine differences between full-time and part-time students.Methods:We conducted a cross-sectional study in a hospital-based nursing school.EI level was measured using the Schutte Self-report Emotional Intelligence Scale(SSEIS).Results:We recruited 287 participants(mean age:21.9 years).Their mean SSEIS score was 119.6(95%CI=118.57-120.65).The mean SSEIS scores of 172 full-time and 115 part-time nurses were 120.7(95%CI=119.3-122.0)and 118.1(95%CI=116.5-119.6),respectively.There was no significant difference between the groups.Conclusion:The EI difference between full-time and part-time nursing students was statistically insignificant.The need for further EI development among both full-time and part-time students must be addressed. 展开更多
关键词 emotional intelligence nursing education nursing students HOSPITAL-BASED FULL-TIME PART-TIME cross-sectional study
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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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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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Study of remote efficacy and safety of acupuncture on cerebral infarction at recovery phase:multi-central randomized comparison trial 被引量:4
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作者 杨志新 卞金玲 +6 位作者 许军峰 申鹏飞 熊杰 郭家奎 张智龙 李军 石学敏 《World Journal of Acupuncture-Moxibustion》 2009年第2期5-12,共8页
Objective To explore the remote efficacy and safety of consciousness-restoring resuscitation (Xingnao Kaiqiao, short for XNKQ) acupuncture on cerebral infarction at recovery phase. Methods Two hundred and thirty-fou... Objective To explore the remote efficacy and safety of consciousness-restoring resuscitation (Xingnao Kaiqiao, short for XNKQ) acupuncture on cerebral infarction at recovery phase. Methods Two hundred and thirty-four cases of cerebral infarction at recovery phase were randomized into XNKQ group and routine acupuncture group (routine group) in light of SAS code. One hundred and sixteen cases in the XNKQ group were treated with XNKQ acupuncture (once a day, totally 4 weeks) and routine treatment with western medicine. One hundred and eighteen cases in the routine group received routine acupuncture and routine treatment with western medicine. Follow-up lasted 6 months. Primary indexes: the situations of survival, treatment and recurrence at the end of follow-up. Secondary indexes: assessment of nerve functions at the end of follow-up and rate of adverse events during acupunc- ture. Results In 6 months follow-up, the mortality was 0.86% and rate of continuous treatment was 36.21% in the XNKQ group and they were 1.69% and 36.44% respectively in the routine group. The differences did not present statistical significance between the two groups (X^2 = 0.29, P=0.59; X^2 = 0.32, P = 0.57). Concerning to the decrease of recurrence rate and improvement of nerve functions, the out-comes in the XNKQ group were superior to those in the routine group (P〈0.01). Severe adverse events did not happen in the two groups. Conclusion XNKQ acupuncture is safe therapy and its remote efficacy is superior to that of routine acupuncture in the decrease of recurrence rate and improvement of nerve functions. 展开更多
关键词 Cerebral Infarction Acupuncture Therapy Consciousness-Restoring Resuscitation Randomized Controlled Trial Therapeutic Results Follow-up study
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Comparison study on calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949 被引量:1
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作者 淳庆 Van Balen Koenraad 韩宜丹 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期529-534,共6页
In order to study the calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949, tests on the mechanical performance of 66 rebars from different modem Chinese concrete buildings, t... In order to study the calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949, tests on the mechanical performance of 66 rebars from different modem Chinese concrete buildings, the concrete compressive strength of 12 modem Chinese concrete buildings, and the concrete cover thickness of 9 modem Chinese concrete buildings are carried out; and the actual material properties and structural conformations of modem Chinese concrete buildings are obtained. Then, the comparison on calculation methods of bending behavior including the original Chinese calculation method, the present Chinese calculation method, the present American calculation method and the present European calculation method is studied. The results show that the original Chinese calculation method of bending behavior is based on the allowable stress calculation method, and the design safety factors are 3.55 to 4. 0. In term of the calculation area of longitudinal rebars of reinforced concrete beams, without considering earthquake action, the original Chinese structural calculation method is safer than the present Chinese structural calculation method, the present European structural calculation method, and the present American structural calculation method. The results can provide support for the structural safety assessments of modem Chinese reinforced concrete buildings. 展开更多
关键词 reinforced concrete beam the Republic of China era from 1912 to 1949 bending behavior calculation method comparative study
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A Comparison study of First and Second Language Acquisition 被引量:2
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作者 赵健 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S1期339-341,共3页
More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relati... More focuses of foreign language teaching theory and practice are on the study of first language and second language acquisition. The article deals with the concept of first and second language acquisition, the relationship between them and the factors influencing on them. The characteristics of the children acquisition and adult acquisition are also studied. 展开更多
关键词 first language acquisition second language acquisition comparison study
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A Comparison Study of Tropical Pacific Ocean State Estimation:Low-Resolution Assimilation vs.High-Resolution Simulation 被引量:5
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作者 符伟伟 朱江 +1 位作者 周广庆 王会军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第2期212-219,共8页
A comparison study is performed to contrast the improvements in the tropical Pacific oceanic state of a low-resolution model respectively via data assimilation and by an increase in horizontal resolution. A low resolu... A comparison study is performed to contrast the improvements in the tropical Pacific oceanic state of a low-resolution model respectively via data assimilation and by an increase in horizontal resolution. A low resolution model (LR) (1°lat by 2°lon) and a high-resolution model (HR) (0.5°lat by 0.5°lon) are employed for the comparison. The authors perform 20-yr numerical experiments and analyze the annual mean fields of temperature and salinity. The results indicate that the low-resolution model with data assimilation behaves better than the high-resolution model in the estimation of ocean large-scale features. From 1990 to 2000, the average of HR's RMSE (root-mean-square error) relative to independent Tropical Atmosphere Ocean project (TAO) mooring data at randomly selected points is 0.97℃ compared to a RMSE of 0.56℃ for LR with temperature assimilation. Moreover, the LR with data assimilation is more frugal in computation. Although there is room to improve the high-resolution model, the low-resolution model with data assimilation may be an advisable choice in achieving a more realistic large-scale state of the ocean at the limited level of information provided by the current observational system. 展开更多
关键词 comparison study high-resolution model data assimilation low-resolution model
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A comparison study of two Tricept units for reconfigurable parallel kinematic machines 被引量:2
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作者 石俊山 Tang Xiaoqiang Lin Chunshen Wang Liping 《High Technology Letters》 EI CAS 2005年第4期392-396,共5页
This paper presents a comparison study of workspace and dexterity of two Tricept units for Reconfigurable Parallel Kinematic Machines (RPKMs). The modular leg of RPKMs is designed and the RPKMs can be built by chang... This paper presents a comparison study of workspace and dexterity of two Tricept units for Reconfigurable Parallel Kinematic Machines (RPKMs). The modular leg of RPKMs is designed and the RPKMs can be built by changing tile setting of modules. A compositive kinematic model is developed accordingly. The inverse kinematics and Jacobian of these two Trieept units are analyzed. Considering workspaee volume and dexterity, the effeets of geometric size of some modules on the two Trieept units are discussed. In the end, comparison results of these two Tricept units are. given. The eomparison of two kinds of Parallel Kinematic Machines (PKMs) can be of help in the design and configuration planning of the RPKMs. 展开更多
关键词 RPKMs comparison study DEXTERITY WORKSPACE
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A Comparison Study of Hydrogen Storage Thermodynamics and Kinetics of YMg11Ni Alloy Prepared by Melt Spinning and Ball Milling 被引量:3
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作者 Yang-Huan Zhang Wei Zhang +3 位作者 Jin-Liang Gao Ze-Ming Yuan Wen-Gang Bu Yan Qi 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第11期1040-1048,共9页
Melt spinning (MS) and ball milling (BM) were employed to fabricate YMg11Ni alloy, and their structures and hydrogen storage performances were examined. The results reveal that the as-spun and as-milled alloys bot... Melt spinning (MS) and ball milling (BM) were employed to fabricate YMg11Ni alloy, and their structures and hydrogen storage performances were examined. The results reveal that the as-spun and as-milled alloys both exhibit the nanocrystalline and amorphous structure. The as-milled alloy shows a larger hydrogen absorption capacity as compared with the as-spun alloy. More than that, the as-milled alloy exhibits lower onset hydrogen desorption temperature than the as-spun one, which are 549.8 and 560.9 K, respectively. Additionally, the as-milled alloy shows a superior hydrogen desorption property to the as-spun one. On the basis of the time needed by desorbing hydrogen of 3 wt% H2, for the as- milled alloy, it needs 1106, 456, 343, and 180 s corresponding to hydrogen desorption temperatures of 593, 613, 633, and 653 K. However, for the as-spun alloy, the time needed is greater than 2928, 842, 356, and 197 s corresponding to the same temperatures. Hydrogen desorption activation energies of as-milled and as-spun alloys are 98.01 and 105.49 kJ/mol, respectively, which is responsible for that the as-milled alloy possesses a much faster dehydriding rate. By means of the measurement of pressure-composition-temperature (P-C-T) curves, the dehydrogenation enthalpy change of the alloys prepared by MS (△Hoe(MS)) and BM (△Hdc(BM)) is 81.84 and 79.46 kJ/mol, respectively, viz. △Hde(MS) 〉 △Hoc(BM). 展开更多
关键词 Mg-based alloy Ball milling Melt spinning Hydrogen storage kinetics comparison
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Comparison Study on the Microstructure of Nanocrystalline TiO_2 in Different Ti-Si Binary Oxides 被引量:1
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作者 Luyan WANG Yanping SUN Bingshe XU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第5期604-610,共7页
Three different Ti-Si oxide structuares, silica supported titania, silica coated titania and intimately mixed silicatitania, containing 10%-40% SiO2, were made by sol-gel process. The variations of microstructure para... Three different Ti-Si oxide structuares, silica supported titania, silica coated titania and intimately mixed silicatitania, containing 10%-40% SiO2, were made by sol-gel process. The variations of microstructure parameters of nanocrystalline (nc) TiO2-anatase in the three kirds of binary oxides, including in-plane spacing d, cell constants (ao, co), cell volume V, cell axial ratio co/ao and crystal grain size, were comparatively investigated by high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). It is found that the microstructure parameters vary remarkably with increasing SiO2 content and annealing temperature. Different structured Ti-Si binary oxides lead to different variation tendencies of microstructure parameters. The more SiO2 the binary oxide contains, the more lattice defects of nc TiO2-anatase appear; diffusion or migration of Si cations could be an important influential factor in the variations of microstructure. The grain size of nc TiO2 in the three kinds of binary oxides not only depends on SiO2 content and annealing temperature but also on the degree of lattice microstrain and distortion of nc TiO2-anatase. Both grain size and phase transformation of nc TiO2-anatase are effectively inhibited with increasing SiO2 content. 展开更多
关键词 Ti-Si binary oxide SOL-GEL Microstructure parameter comparison
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Interspecific comparison of the flight performance between sparrowhawks and common buzzards migrating at the Falsterbo peninsula: A radar study 被引量:4
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作者 Gintaras MALMIGA Cecilia NILSSON Johan BACKMAN Thomas ALERSTAM 《Current Zoology》 SCIE CAS CSCD 2014年第5期670-679,共10页
In order to compare the two species' flight performance over the exposed and windy Falsterbo Peninsula, where thermal conditions seldomly are very favorable, we used tracking radar to study flight parameters of sparr... In order to compare the two species' flight performance over the exposed and windy Falsterbo Peninsula, where thermal conditions seldomly are very favorable, we used tracking radar to study flight parameters of sparrowhawks Accipiter ni- sus and common buzzards Buteo buteo during autumn migration. The results showed a clear difference between sparrowhawks and common buzzards in their flight altitudes and speeds, and in the wind conditions they encountered. Common buzzards had higher flight altitudes and were more selective of wind. Flight altitude was negatively related to the wind speed, which was most pronounced for common buzzards. Sparrowhawks had higher mean air- and cross-country speeds than common buzzards. Air- speed was negatively related, whereas ground and cross-country speeds were positively related to the tailwind component for both raptors. The differences between sparrowhawks and buzzards could to a large degree be explained by a larger dependence on thermal soaring among the common buzzards; a strategy associated with selectivity for favourable thermal and wind conditions during migratory flight. An additional important explanation for the interspecific differences was the habit of the sparrowhawks to combine migratory flight with hunting for prey, which makes it prone to fly at lower altitudes and use flapping flight to a much larger degree than common buzzards which do not forage during their migratory passage of the Falsterbo Peninsula [Current Zoo- logy 60(5): 670-679, 2014]. 展开更多
关键词 Tracking radar Raptor migration Sparrowhawk Common buzzard Flight performance Interspecific comparison Falsterbo peninsula
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A Model Comparison Study of Fragment Production in 140 A MeV 58,64Ni+9Be Reactions
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作者 马春旺 张艳丽 +1 位作者 王闪闪 乔春源 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期29-33,共5页
The cross sections of fragments produced in the 140 A MeV58,64Ni+9 Be projectile fragmentation reactions are calculated by using the antisymmetrized molecular dynamics (AMD) model, the modified statistical abrasion... The cross sections of fragments produced in the 140 A MeV58,64Ni+9 Be projectile fragmentation reactions are calculated by using the antisymmetrized molecular dynamics (AMD) model, the modified statistical abrasion- ablation (SAA) model, and the empirical EPAX2/EPAX3 formulae. The Gogny-gO interaction is taken as the effective nucleon-nucleon interaction in the AMD calculation, and the decays of fragments obtained from the AMD results are calculated by using the GEMINI code. The calculated cross sections of fragments are compared. 展开更多
关键词 BE A Model comparison study of Fragment Production in 140 A MeV REACTIONS AMD NI
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Comparison of dimension reduction-based logistic regression models for case-control genome-wide association study:principal components analysis vs.partial least squares 被引量:2
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作者 Honggang Yi Hongmei Wo +9 位作者 Yang Zhao Ruyang Zhang Junchen Dai Guangfu Jin Hongxia Ma Tangchun Wu Zhibin Hu Dongxin Lin Hongbing Shen Feng Chen 《The Journal of Biomedical Research》 CAS CSCD 2015年第4期298-307,共10页
With recent advances in biotechnology, genome-wide association study (GWAS) has been widely used to identify genetic variants that underlie human complex diseases and traits. In case-control GWAS, typical statistica... With recent advances in biotechnology, genome-wide association study (GWAS) has been widely used to identify genetic variants that underlie human complex diseases and traits. In case-control GWAS, typical statistical strategy is traditional logistical regression (LR) based on single-locus analysis. However, such a single-locus analysis leads to the well-known multiplicity problem, with a risk of inflating type I error and reducing power. Dimension reduction-based techniques, such as principal component-based logistic regression (PC-LR), partial least squares-based logistic regression (PLS-LR), have recently gained much attention in the analysis of high dimensional genomic data. However, the perfor- mance of these methods is still not clear, especially in GWAS. We conducted simulations and real data application to compare the type I error and power of PC-LR, PLS-LR and LR applicable to GWAS within a defined single nucleotide polymorphism (SNP) set region. We found that PC-LR and PLS can reasonably control type I error under null hypothesis. On contrast, LR, which is corrected by Bonferroni method, was more conserved in all simulation settings. In particular, we found that PC-LR and PLS-LR had comparable power and they both outperformed LR, especially when the causal SNP was in high linkage disequilibrium with genotyped ones and with a small effective size in simulation. Based on SNP set analysis, we applied all three methods to analyze non-small cell lung cancer GWAS data. 展开更多
关键词 principal components analysis partial least squares-based logistic regression genome-wide association study type I error POWER
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A computational simulation study for techno-economic comparison of conventional and stripping gas methods for natural gas dehydration 被引量:4
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作者 Muhammad Salman Liangliang Zhang Jianfeng Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第9期2285-2293,共9页
In the present work,the conventional natural gas dehydration method(CDM)and stripping gas method(SGM)are technically and economically analyzed,utilizing Aspen HYSYS and Aspen Process Economic Analyzer(APEA),respective... In the present work,the conventional natural gas dehydration method(CDM)and stripping gas method(SGM)are technically and economically analyzed,utilizing Aspen HYSYS and Aspen Process Economic Analyzer(APEA),respectively.To optimize the CDM and SGM,the sensitivities of the water content of dry gas,reboiler duty and raw material loss are analyzed against solvent rate and stripping gas rate.The optimized processes are set to achieve a targeted value of water content in dry gas and analyzed at optimized point.The analysis shows that SGM gives 46%lower TEG feed rate,42%lower reboiler duty and 99.97%pure regenerated TEG.Moreover,economic analysis reveals that SGM has 38%lower annual operating cost compared to CDM.According to results,from both technical and economic point of view,SGM is more feasible for natural gas dehydration compared to CDM. 展开更多
关键词 Natural gas dehydration Technical analysis Parametric optimization Economic study Aspen HYSYS
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