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Fully Developed Turbulence of Power⁃Law Fluids in Circular Pipe Based on Large Eddy Simulation

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Journal of Harbin Institute of Technology(New Series) 2021年第4期28卷 67-76页

作者： Shuyan Wang Miao Li Shuqing Wang Haoting Li Yujia Chen yimei ma Qiji Sun School of Petroleum Engineering Northeast Petroleum UniversityDaqing 163318HeilongjiangChina Key Laboratory of Enhanced Oil Recovery(Northeast Petroleum University) Ministry of EducationDaqing 163318HeilongjiangChina The Fourth Oil Production Factory Daqing Oilfield Corporation Ltd.Petro ChinaDaqing 163511HeilongjiangChina

In this study,Large eddy simulation(LES)of the fully developed turbulence of power⁃law fluids in a circular pipe was performed using the dynamic subgrid⁃scale model.Under a specific Reynolds number,the flow information of three fluids with a range of power⁃law indexes was obtained.The trends of the mean axial velocity and the normalized apparent viscosity were analyzed.Simulation results show that shearing⁃thinning fluid displayed more noticeable non⁃Newtonian characteristics than shear⁃thickening fluid.The predicted friction factors were approximately equal to the Dodge and Metzner correlation and Gomes correlation.The peak values of root mean squares(RMS)and Reynolds stress increased as the power⁃law index increased.The turbulence statistics(skewness and flatness)from the wall to the pipe center were calculated.From the calculated results,the velocity fluctuation near the wall had strong intermittent and asymmetry.As demonstrated by the contours of the normalized instantaneous axial velocity and viscosity,the turbulence was more developed as the power⁃law index increased.It is concluded that the LES is feasible to predict the turbulence of pipe flow under higher Reynolds numbers.

关键词： Large eddy simulation power⁃law fluids fully developed turbulence

老年支气管哮喘伴睡眠障碍患者应用孟鲁司特钠片辅助甲泼尼龙治疗效果观察

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首都食品与医药 2024年第7期31卷 77-79页

作者：兰秋艳沈赛赛丁春艳马义梅新疆军区乌鲁木齐第五离职干部休养所新疆乌鲁木齐830002 新疆军区乌鲁木齐第一离职干部休养所新疆乌鲁木齐830000 新疆四七四医院新疆乌鲁木齐830000

目的观察老年支气管哮喘伴睡眠障碍患者应用孟鲁司特钠片辅助甲泼尼龙治疗的效果。方法以新疆军区乌鲁木齐第五离职干部休养所门诊部于2021年1月-2023年1月收治的老年支气管哮喘伴睡眠障碍患者80例为研究观察对象,将患者依据随机数字表... 详细信息

目的观察老年支气管哮喘伴睡眠障碍患者应用孟鲁司特钠片辅助甲泼尼龙治疗的效果。方法以新疆军区乌鲁木齐第五离职干部休养所门诊部于2021年1月-2023年1月收治的老年支气管哮喘伴睡眠障碍患者80例为研究观察对象,将患者依据随机数字表法分为两组,即对照组(孟鲁司特钠片治疗)、实验组(孟鲁司特钠片+甲泼尼龙治疗),观察两组患者临床疗效、肺功能、睡眠质量、炎症情况、不良反应发生率。结果实验组治疗后治疗总有效率高于对照组,差异有统计学意义(P0.05)。结论治疗老年支气管哮喘伴睡眠障碍患者采用孟鲁司特钠片辅助甲泼尼龙治疗的总有效率高,明显改善患者睡眠情况、肺功能情况、炎症情况,治疗安全性较好,可推广应用。

关键词：孟鲁司特钠片支气管哮喘睡眠障碍甲泼尼龙肺功能

本科生导师制度对临床医学专业学生科研能力的影响

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中国继续医学教育 2024年第10期16卷 112-116页

作者：马义梅陆晓茜郭霞高举刘瀚旻四川大学华西第二医院儿童血液肿瘤科四川成都610041 四川大学出生缺陷与相关妇儿疾病教育部重点实验室四川成都610041 四川大学华西第二医院小儿呼吸免疫科四川成都610041 国家卫生健康委员会时间生物学重点实验室四川成都610041

目的评价本科生导师制度对临床医学专业学生科研能力的影响。方法 2023年5-6月,通过调查问卷的方式,将四川大学华西临床医学院临床医学专业全日制本科生160名纳入调查对象。采用问卷调查的方式分析临床医学专业本科生的基本情况、科研... 详细信息

目的评价本科生导师制度对临床医学专业学生科研能力的影响。方法 2023年5-6月,通过调查问卷的方式,将四川大学华西临床医学院临床医学专业全日制本科生160名纳入调查对象。采用问卷调查的方式分析临床医学专业本科生的基本情况、科研产出以及对本科生导师制度的态度、现状与建议。根据本科生科研产出的相关因素,将所有调查对象分为科研产出组和无产出组。比较2组本科生导师科室、本科生导师职称、与导师见面频次的差异。结果本次调查共发放调查问卷160份,回收153份,有效回收率95.6%。110名(71.9%)学生支持实施本科生导师制度,96名(62.7%)学生表示本科生导师制度有助于提升和锻炼自己的科研能力。在完善本科生导师制度的建议方面,83.7%的学生建议增加与导师见面的频次。调查结果显示,有科研产出者89人(58.2%),无科研产出者64人(41.8%)。科研产出组和无产出组学生在性别、本科生导师科室、本科生导师职称方面比较,差异无统计学意义(P> 0.05)。产出组学生与导师见面的高频次共38名(42.7%),中频次共34名(38.2%),低频次共17名(19.1%);无产出组,学生与导师见面的高频次共17名(26.6%),中频次共19名(29.7%),低频次共28名(43.8%)。产出组和无产出组学生与导师见面的频次比较,差异有统计学意义(P <0.05)。结论本科生导师制度有效地提高了临床医学生的科研能力,增加了科研产出。本科生导师与学生的联系频次影响学生的科研产出。

关键词：本科生导师制度临床医学专业调查问卷科研能力科研产出人才培养

儿童烧伤创面操作性疼痛非药物管理的最佳证据总结

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中华损伤与修复杂志（电子版） 2024年第2期19卷 159-164页

作者：刘芳黄纯渊王凤林马轶美汤焘侯文佳刘蕾上海交通大学医学院附属上海儿童医学中心烧伤整复外科 200127 华中科技大学同济医学院附属协和医院感染科武汉430022

目的总结儿童烧伤创面操作性疼痛非药物管理的最佳证据。方法采用文献计量学方法。系统检索UpToDate、BMJ Best Practice、Cochrane Library、PubMed、Embase、Web of Science、CINAHL、Registered Nurses′Association of Ontario、Scottish Intercollegiate Guidelines Network、New Zealand Guidelines Group、Joanna Briggs Institute Evidence-Based Practice Database、American Burn Association、中国知网、万方数据库、维普数据库、中国生物医学文献服务系统、医脉通、梅斯医学等数据库公开发表的关于儿童烧伤创面操作性疼痛非药物管理的所有证据,包括指南、临床决策、证据总结、推荐实践、专家共识、系统评价,检索时限为建库至2023年8月。筛选文献并评价文献质量,从中提取证据并进行评价,总结最佳证据。结果纳入文献15篇,包括指南3篇、临床决策3篇、证据总结3篇、系统评价6篇,从疼痛多维度评估与识别,非药物管理原则、方法及注意事项,社会干预,健康教育,建立多学科团队,换药操作技术方面总结出31条最佳证据。结论从8个方面总结出31条有关儿童烧伤创面操作性疼痛非药物管理的最佳证据,可为临床烧伤患儿创面换药实践提供决策依据。

关键词：烧伤儿童操作性疼痛非药物干预证据总结

Ultrathin Zincophilic Interphase Regulated Electric Double Layer Enabling Highly Stable Aqueous Zinc‑Ion Batteries

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Nano-Micro Letters 2024年第5期16卷 285-299页

作者： yimei Chen Zhiping Deng Yongxiang Sun Yue Li Hao Zhang Ge Li Hongbo Zeng Xiaolei Wang Department of Chemical and materials Engineering University of Alberta9211‑116 Street NWEdmontonAB T6G 1H9Canada Department of Mechanical Engineering University of Alberta9211‑116 Street NWEdmontonAB T6G 1H9Canada

The practical application of aqueous zinc-ion batteries for large-grid scale systems is still hindered by uncontrolled zinc dendrite and side reactions.Regulating the elec-trical double layer via the electrode/electrolyte interface layer is an effective strategy to improve the stability of Zn anodes.Herein,we report an ultrathin zincophilic ZnS layer as a model regu-lator.At a given cycling current,the cell with Zn@ZnS electrode displays a lower potential drop over the Helmholtz layer(stern layer)and a suppressed diffuse layer,indicating the regulated charge distribution and decreased electric double layer repulsion force.Boosted zinc adsorption sites are also expected as proved by the enhanced electric double-layer capacitance.Consequently,the symmetric cell with the ZnS protection layer can stably cycle for around 3,000 h at 1 ma cm^(-2) with a lower overpotential of 25 mV.When coupled with an I2/AC cathode,the cell demonstrates a high rate performance of 160 mah g^(-1) at 0.1 A g^(-1) and long cycling stability of over 10,000 cycles at 10 A g^(-1).The Zn||MnO_(2) also sustains both high capacity and long cycling stability of 130 mah g^(-1) after 1,200 cycles at 0.5 A g^(-1).

关键词： Zinc anode Electric double-layer regulation Multifunction SEI layer Inhibited side reactions and dendrite Rapid kinetics

Network analysis of suicide ideation and depression-anxiety symptoms among Chinese adolescents

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General Psychiatry 2024年第2期37卷 216-223页

作者： Shuyin Xu Yumeng Ju Xiyu Wei Wenwen Ou Mohan ma Guanyi Lv Xiaotian Zhao Yaqi Qin Yunjing Li Liang Li Mei Huang Siqi Yang yimei Lu Yafei Chen Junwu Liu Jin Liu Bangshan Liu Yan Zhang Department of Psychiatry National Clinical Research Center for Mental Disordersand National Center for Mental DisordersThe Second Xiangya Hospital of Central South UniversityChangshaHunanChina Mental Health Institute of Central South University China National Technology Institute on Mental DisordersHunan Technology Institute of PsychiatryHunan Key Laboratory of Psychiatry and Mental HealthHunan Medical Center for Mental HealthChangshaHunanChina

Background The co-occurrence of depression and anxiety among adolescents is typically associated with suicide ideation.Aims The study aimed to investigate the symptom-level relationship between suicide ideation and the comorbidity of depression and anxiety.Methods 1501 adolescents aged 12-19 years were assessed using the Patient Health Questionnaire(PHQ-9)and the Generalized Anxiety Disorder Scale,and 716 adolescents who scored≥5 on both scales were selected as participants.Network analysis was used to identify the network structure of depressive symptoms and anxiety symptoms.Participants were categorised into either the suicide ideation or non-suicide ideation groups based on their scoring on the suicide-related item in PHQ-9.A comparison was made between the depression-anxiety symptom networks of the two groups.Results‘Restlessness’,‘sad mood’and‘trouble relaxing’were the most prominent central symptoms in the depression-anxiety symptom network,and‘restlessness’,‘nervousness’and‘reduced movement’were the bridge symptoms in this network.‘Sad mood’was found to be directly related to‘suicide ideation’with the highest variance.The network structure was significantly different in properties between the suicide ideation group and the non-suicide ideation group,with‘restlessness’and‘sad mood’exhibiting significantly higher influence in the network of the suicide ideation group than that in the non-suicide ideation group.Conclusion Restlessness and sad mood could be targeted for the intervention of depression-anxiety symptoms among adolescents with suicide ideation.

关键词： symptoms adolescent assessed

VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

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Journal of Environmental Sciences 2024年第1期135卷 570-584页

作者： Jiawei ma Lin Li State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for VOCs Pollution Control material&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises.In the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing compounds.Ketones were the main components of waste gases,accounting for 44.13%-77.85%of the overall VOCs.Process-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions.Dimethyl heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system.Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind.Furthermore,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs.Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharmaceutical Volatile organic compound Priority pollutant Exposure risk Secondary pollution

Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang Hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and families.Additionally, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implications of nuclear phylogenomic analyses on ancestral

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny

Uniform decomposition of velocity gradient tensor

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Journal of Hydrodynamics 2024年第1期36卷 24-34页

作者： Chenxi ma Chaoqun Liu Department of mathematics University of Texas at ArlingtonArlingtonTXUSA

In this paper,the principal decomposition of the velocity gradient tensor[∇v]is discussed in 3 cases based on the discriminant∆:∆0 with 3 distinct real eigen values,and∆=0 with 1 or 2 distinct real eigen values.The velocity gradient tensor can also be classified as rotation point,which can be decomposed into three parts,i.e.,rotation[R],shear[S]and stretching/compression[SC],and non-rotation point,we defined a new resistance term[L],and the tensor can be decomposed into three parts,i.e.,resistance[L],shear[S]and stretching/compression[SC].Example matric are also displayed to demonstrate the new decomposition.Connections of principal decomposition between 3 different cases,and between Resistance and Liutex will also be discussed.

关键词： Velocity gradient Liutex resistance fluid kinematics