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基于高仿真模型的模拟教学在剖宫产手术技能培训中的应用
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作者 郧丰 江若安 +3 位作者 诸林华 李雯 吕圆 徐冬 《首都食品与医药》 2025年第13期109-112,共4页
目的探讨基于高仿真模型的模拟教学在剖宫产手术技能培训中的适用性及教学效果。方法选取产科低年资医师33人,其中实验组(n=17)接受高仿真剖宫产手术模型培训,对照组(n=16)采用简单模型进行培训。通过问卷调查两组对培训课程、模型等的... 目的探讨基于高仿真模型的模拟教学在剖宫产手术技能培训中的适用性及教学效果。方法选取产科低年资医师33人,其中实验组(n=17)接受高仿真剖宫产手术模型培训,对照组(n=16)采用简单模型进行培训。通过问卷调查两组对培训课程、模型等的评价。结果实验组对模型操作课程的实用性和满意度评分显著高于对照组(P<0.05),且对模型拟真度的评价更高(P<0.01)。结论基于高仿真模型的模拟教学适用于产科低年资医师的剖宫产手术技能培训,教学效果良好。未来有必要扩大样本量并优化评价标准,进一步发掘其在临床教学中的应用潜力。 展开更多
关键词 剖宫产手术 模拟教学 高仿真模型 住院医师培训
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碱式硫酸铝脱硫富液压力与温度对解吸性能的影响
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作者 张子敬 杨淼 +4 位作者 刘运巍 云峰 李中义 王聪宇 张颖 《当代化工》 2025年第1期16-20,26,共6页
如何在较低的温度下获得较高的解吸性能是解决碱式硫酸铝解吸法脱硫的重要环节。对比常压热解吸研究了负压和解吸温度匹配关系对解吸性能的影响规律。结果表明:虽然提高温度和降低压力均能提高解吸率,但压力越低温度对解吸率提高的影响... 如何在较低的温度下获得较高的解吸性能是解决碱式硫酸铝解吸法脱硫的重要环节。对比常压热解吸研究了负压和解吸温度匹配关系对解吸性能的影响规律。结果表明:虽然提高温度和降低压力均能提高解吸率,但压力越低温度对解吸率提高的影响程度越高。相比80℃常压解吸的最优工况,降低压力至70 kPa和80 kPa,60℃仍具有等价的解吸能力,解吸率提高量分别为-0.52%~2.01%和-2.63%~-0.44%。进一步提高解吸温度至70℃和80℃,解吸率提高量随时间呈先增加后减少的变化规律,40 min达到最大值,且70 kPa相比80 kPa分别提高4.42%和1.63%。较高的解吸温度和较低的解吸压力对解吸速率的提高同样有利,但降低压力至80 kPa需要提高解吸温度或延长解吸时间才能发挥出更高的解吸潜能,过高的温度由于SO32-浓度较低导致解吸性能的提高能力变弱。相比90 kPa降低至80 kPa,压力从80 kPa降低至70 kPa的解吸速率提高幅度大幅降低至50%左右。实验工况最佳的压力与温度匹配关系为70 kPa、70℃。 展开更多
关键词 碱式硫酸铝 脱硫富液 负压解吸 温度
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一种轴承动、静态载荷摩擦力矩测量试验技术
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作者 孙勇 云峰 +4 位作者 孙宝瑞 何雨奇 焦杰 李洪营 邹杰 《工程与试验》 2025年第4期81-84,共4页
本文研究了一种采用平衡法测量轴承摩擦力矩的试验技术,可在动态工况下对轴承摩擦力矩进行准确测量。轴承摩擦阻力是影响轴承寿命的一项重要指标,也是影响轴承相关系统可靠性、精确性和安全性的重要因素。轴承动、静态载荷摩擦力矩测量... 本文研究了一种采用平衡法测量轴承摩擦力矩的试验技术,可在动态工况下对轴承摩擦力矩进行准确测量。轴承摩擦阻力是影响轴承寿命的一项重要指标,也是影响轴承相关系统可靠性、精确性和安全性的重要因素。轴承动、静态载荷摩擦力矩测量试验机是轴承试验检测中的一种多功能试验装备,其功能丰富、应用领域广泛,可精确检测各种滚动轴承在不同环境、不同载荷、不同转速下的动态力矩等性能。 展开更多
关键词 轴承 摩擦力矩 摩擦阻力 试验机 测量原理 闭环控制
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Causal relationship between multiple types of food intake and myopia:a Mendelian randomization study
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作者 Sha-Sha Zhang Jiao-Jiao Liang +4 位作者 yun feng Xia Hong Yi-Jia Zhao Ling Chen Ping Lin 《International Journal of Ophthalmology(English edition)》 2025年第9期1718-1729,共12页
AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to e... AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to examine associations between myopia and various dietary factors.MR analysis,incorporating both univariable and multivariable approaches,assessed the impact of food intake on myopia risk through five analytical methods,with inverse variance weighted(IVW)serving as the primary reference.Sensitivity analyses,including heterogeneity assessment,horizontal pleiotropy evaluation,and leave-oneout analysis,were conducted to validate the MR findings.RESULTS:Univariable MR analysis identified a causal link between food intake and myopia.Consumption of breaded fish,canned soup,sweet biscuits,and certain fruits correlated with a lower risk of myopia,whereas intake of low-calorie hot chocolate and cereal was associated with an increased risk.Multivariable MR analysis further confirmed that breaded fish consumption exerted a direct protective effect against myopia,particularly when consumed alongside other dietary components.These findings highlight the intricate interplay between specific dietary factors and myopia development,offering valuable insights for further research.CONCLUSION:MR analysis provides evidence supporting a potential causal relationship between breaded fish intake and myopia,underscoring its relevance in targeted myopia prevention strategies. 展开更多
关键词 MYOPIA genome-wide association study food intakes univariable Mendelian randomization analysis multivariable Mendelian randomization analysis
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Adaptive Control of a Flexible Manipulator With Unknown Hysteresis and Intermittent Actuator Faults
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作者 Shouyan Chen Weitian He +3 位作者 Zhijia Zhao yun feng Zhijie Liu Keum-Shik Hong 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期148-158,共11页
In this study,we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults.First,an inverse hysteresis dynamics model is introduced,and then... In this study,we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults.First,an inverse hysteresis dynamics model is introduced,and then the control input is divided into an expected input and an error compensator.Second,a novel adaptive neural network-based control scheme is proposed to cancel the unknown input hysteresis.Subsequently,by modifying the adaptive laws and local control laws,a fault-tolerant control strategy is applied to address uncertain intermittent actuator faults in a flexible manipulator system.Through the direct Lyapunov theory,the proposed scheme allows the state errors to asymptotically converge to a specified interval.Finally,the effectiveness of the proposed scheme is verified through numerical simulations and experiments. 展开更多
关键词 Adaptive control flexible manipulator intermittent actuator faults inverse hysteresis dynamics vibration control
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Identifying ATP-Binding CassetteMember B5 as a New Biomarker for Oral Squamous Cell Carcinoma
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作者 Li Yu Xiaoyan Zhang +6 位作者 Yan feng Xinyue Liao Tiejun Zhou Hang Si yun feng Decai Wang Yongxian Lai 《Oncology Research》 2025年第8期2037-2053,共17页
Background:Oral squamous cell carcinoma(OSCC)is the most common head and neck malig-nancy with a low five-year survival rate.ATP-binding cassette subfamily B member 5(ABCB5)has been linked to tumorigenesis.However,its... Background:Oral squamous cell carcinoma(OSCC)is the most common head and neck malig-nancy with a low five-year survival rate.ATP-binding cassette subfamily B member 5(ABCB5)has been linked to tumorigenesis.However,its role in inducing OSCC remains unclear.Methods:Quantitative reverse transcription polymerase chain reaction(qRT-PCR),western blot,and immunocytochemistry(ICC)were performed to examine the level of ABCB5 in OSCC(CAL27 and HSC-3)and human oral keratinocyte(HOK).ABCB5 was knocked down in CAL27 cells using ABCB5-specific small interfering RNA(ABCB5 siRNA),and its contribution to migration,invasion,and epithelial-mesenchymal transition(EMT),a process by which epithelial cells lose their tight junction and acquire an increased migratory and invasive phenotype resembling that of mesenchymal cells,were evaluated by three-dimension and transwell migration and invasion assays,qRT-PCR and ICC.An in vivo OSCC model was established using 4-nitroquinoline-1-oxide(4NQO),a carcinogenic chemical that is commonly used to develop OSCC by destroying DNA synthesis and oxidative stress.Pathological alterations,ABCB5,and EMT markers were evaluated by H&E staining,immunohistochemistry,and qRT-PCR.Results:ABCB5 was significantly upregulated in CAL27 and HSC-3 cells as compared to HOK.Knockdown of ABCB5 significantly reduced the number of migrated and invaded CAL27 cells,accompanied by the significantly increased E-cadherin and decreased Vimentin and N-cadherin under Transforming growth factorβ(TGF-β)treatment.In vivo,as OSCC advanced,a notable rise in the expressions of ABCB5,N-cadherin,and Vimentin,while a statistical decrease in E-cadherin was demonstrated.Conclusion:ABCB5 promotes the migration,invasion,and EMT of OSCC.ABCB5 might be a new biomarker and potential therapeutic target for OSCC. 展开更多
关键词 Oral squamous cell carcinoma(OSCC) ATP-binding cassette subfamily B member 5(ABCB5) migration INVASION epithelial-mesenchymal transition(EMT)
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某换流站调相机转子叶片断裂故障失效分析
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作者 刘高飞 田博海 +9 位作者 赵敏 梁启军 王志惠 贾海龙 云峰 李生龙 莫冰玉 张丰丽 陈莲君 张烁 《青海电力》 2025年第2期81-91,共11页
利用化学成分检测、微观形貌检测、金相检测、力学性能检测、断口形貌分析及有限元仿真等试验方法对某换流站调相机转子叶片断裂原因进行了分析。得出该叶片属于疲劳断裂,叶片螺纹牙底圆弧偏小、牙型角偏小,螺纹牙底应力超出材料许用安... 利用化学成分检测、微观形貌检测、金相检测、力学性能检测、断口形貌分析及有限元仿真等试验方法对某换流站调相机转子叶片断裂原因进行了分析。得出该叶片属于疲劳断裂,叶片螺纹牙底圆弧偏小、牙型角偏小,螺纹牙底应力超出材料许用安全应力规范值,造成服役状态叶片螺纹处萌生初始裂纹。在运行过程中,因转速、振动、风压波动中产生交变应力,造成叶片裂纹疲劳发展,螺杆受力面逐渐降低,当应力超过限值后,被径向载荷瞬间拉断。为防止再次出现调相机转子叶片断裂故障提出了针对性的建议。 展开更多
关键词 调相机 转子叶片 断裂 铝合金 失效分析
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六维加载试验平台运动学建模与仿真
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作者 何雨奇 孙勇 +6 位作者 云峰 董凌宇 梁超 陈云超 李洪营 石伟 王伟 《工程与试验》 2025年第1期17-19,共3页
本文研究了大型六维加载试验平台六自由度的运动学位姿反解问题。首先对试验平台的运动位置逆解进行了理论分析,建立了机构的位置逆解数学模型,并基于Matlab/Simulink仿真集成环境建立其Simulink模型,实现了平台位姿逆解实时解算。其次... 本文研究了大型六维加载试验平台六自由度的运动学位姿反解问题。首先对试验平台的运动位置逆解进行了理论分析,建立了机构的位置逆解数学模型,并基于Matlab/Simulink仿真集成环境建立其Simulink模型,实现了平台位姿逆解实时解算。其次,采用多体系统动力学仿真软件Recurdyn建立平台的物理模型,并与Simulink进行联合仿真验证。最后,由所建立的反解模型求解出了加载平台按一定期望姿态运动时各液压缸的伸缩量,为控制平台实现相应运动姿态提供输入量,并将监测的加载平台实际运动姿态参数与期望姿态进行相互对比验证,结果较为精确,证明了所建立的反解模型及解算的正确性。 展开更多
关键词 六自由度 运动学分析 Recurdyn仿真 数学模型 液压缸
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Effect of double-extrusion following by stepwise-hot-rolling on microstructures and mechanical properties of Mg-Gd-Y-Zn-Zr alloy
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作者 Jinjun Wang Muhammad Abubaker Khan +4 位作者 Shang Dai yun feng Han Wang Mohamed A.Afifi Jingyuan Li 《Journal of Magnesium and Alloys》 2025年第9期4327-4345,共19页
Mg alloys with a combination of high strength and excellent ductility are increasingly required for structural applications.This study investigates the influence of advanced processing techniques on the mechanical pro... Mg alloys with a combination of high strength and excellent ductility are increasingly required for structural applications.This study investigates the influence of advanced processing techniques on the mechanical properties and microstructural evolution of Mg-Gd-Y-Zn-Zr alloys.Utilizing a combination of double extrusion and stepwise hot rolling followed by aging treatments,significant enhancements in the mechanical performance of these alloys are demonstrated.The processing techniques applied lead to notable refinement in grain-size and modifications in the microstructure,including the transformation of LPSO phases from 18R to 24R and the dispersion of β phase particles.These microstructural transformations contribute to a substantial increase in yield-strength,ultimate-tensile-strength,and ductility.Furthermore,findings reveal that these improvements are also supported by alterations in material texture,which influence dislocation dynamics as indicated by changes in Kernel Average Misorientation(KAM)values.The combined effect of grain boundary(GB)strengthening,phase distribution,and texture modification elucidates the observed mechanical enhancements.This research provides valuable insights into the design and optimization of Mg-Gd-Y-Zn-Zr alloys for critical applications in aerospace and automotive industries where high strength and ductility are paramount. 展开更多
关键词 Mg-Re alloys Microstructural evolution Mechanical property Advanced processing techniques
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Gut microbiota helps identify clinical subtypes of Parkinson’s disease
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作者 Jing-Yi Wang Rui Xie +5 位作者 yun feng Min-Na Zhang Le He Bo Yang Hong-Gang Wang Xiao-Zhong Yang 《Military Medical Research》 2025年第6期972-974,共3页
Dear Editor,The role of the microbiota-gut-brain axis in Parkinson’s disease(PD)has garnered increasing att ention[1].Among the various empirical subtype systems of PD,motor subtype classifi cation into tremor-domina... Dear Editor,The role of the microbiota-gut-brain axis in Parkinson’s disease(PD)has garnered increasing att ention[1].Among the various empirical subtype systems of PD,motor subtype classifi cation into tremor-dominant(TD)and postural instability and gait diffi culty(PIGD)is the most commonly utilized[2].However,the relationship between gut microbiota and clinical subtypes of PD remains unclear. 展开更多
关键词 Parkinson’s disease Gut microbiota Functional magnetic resonance imaging
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益气健脾汤治疗脾气亏虚型IGT患者的临床观察及对血糖变异系数的影响 被引量:2
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作者 运锋 张靖寅 +2 位作者 李爱平 乔文琪 田源 《中医药学报》 CAS 2024年第8期78-83,共6页
目的:研究益气健脾汤治疗脾气亏虚型糖耐量减低(IGT)患者的疗效以及对血糖波动指数的影响。方法:纳入2023年12月—2024年2月在黑龙江中医药大学附属第三医院内分泌(老年病)科门诊、住院部的60例IGT(脾气亏虚型)患者,按照随机数字表法分... 目的:研究益气健脾汤治疗脾气亏虚型糖耐量减低(IGT)患者的疗效以及对血糖波动指数的影响。方法:纳入2023年12月—2024年2月在黑龙江中医药大学附属第三医院内分泌(老年病)科门诊、住院部的60例IGT(脾气亏虚型)患者,按照随机数字表法分为对照组和治疗组,每组30例。两组患者均给予饮食、宣教、运动等一般基础治疗。对照组在基础治疗的基础上给予阿卡波糖胶囊;治疗组在对照组基础上加用益气健脾汤联合治疗。两组患者均治疗6周。观察两组在治疗前后的空腹血糖(FPG)、2 h血糖(2 h PG)、糖化血红蛋白(HbA1c);甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL);血糖变异系数(GLUCV)、血糖标准差(GLUsd)、平均血糖值(GLUmean)、日内平均血糖波动幅度(MAGE)、日间血糖平均绝对差(MODD)及中医证候评分,并观察其疗程结束时的随访转归情况。结果:治疗6周后,两组患者的糖代谢指标、GLUsd、GLUmean、GLUCV、MAGE、中医证候评分均显著降低(P<0.05),治疗组的糖代谢指标、GLUsd、GLUCV、MAGE、中医证候评分显著低于对照组,差异有统计学意义(P<0.05)。结论:益气健脾汤能有效改善IGT患者症状,调节糖代谢,并能缩小血糖波动,延缓2型糖尿病发生发展,比单纯生活方式干预和阿卡波糖治疗持久有效。 展开更多
关键词 益气健脾汤 糖耐量异常 脾气亏虚 血糖波动
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基于“体用同治”理论探讨调神调脏针刺法治疗围绝经期抑郁 被引量:2
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作者 运锋 李爱平 +2 位作者 张靖寅 乔文琪 田源 《中医药信息》 2024年第7期51-55,共5页
目的:以“体用同治”理论为指导,观察调神调脏针刺法治疗围绝经期抑郁的临床疗效,探讨其对神志病的作用。方法:选取符合纳入标准的围绝经期抑郁患者66例,依据随机数字表随机分为对照组和治疗组。对照组在基础治疗上加用调脏针刺,治疗组... 目的:以“体用同治”理论为指导,观察调神调脏针刺法治疗围绝经期抑郁的临床疗效,探讨其对神志病的作用。方法:选取符合纳入标准的围绝经期抑郁患者66例,依据随机数字表随机分为对照组和治疗组。对照组在基础治疗上加用调脏针刺,治疗组在对照组的基础上加用调神针刺,两组均持续治疗8周。观察两组患者治疗前后HAMD评分、Kupperman评分、血清E_(2)、FSH、LH水平的变化情况,同时比较临床疗效。结果:两组患者治疗后HAMD评分和Kupperman评分均低于治疗前(P<0.05),且治疗组HAMD评分和Kupperman评分均低于对照组(P<0.05)。治疗组临床有效率93.9%(31/33)明显高于对照组87.9%(29/33)(P<0.05)。两组患者治疗后FSH、LH水平均低于治疗前,E_(2)水平高于治疗前(P<0.05),且治疗组FSH、LH水平均低于对照组,E_(2)水平高于对照组(P<0.05)。结论:“体用同治”理论指导下的调神调脏针刺法,可提高围绝经期抑郁患者的临床疗效,改善激素水平、降低HAMD、Kupperman评分,明显改善患者的抑郁状态。 展开更多
关键词 针刺 体用同治 神脏同调 围绝经期抑郁
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Tumor-related fungi and crosstalk with gut fungi in the tumor microenvironment 被引量:1
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作者 Yue Wang Yiwen Wang +3 位作者 Yuhang Zhou yun feng Tao Sun Junnan Xu 《Cancer Biology & Medicine》 CSCD 2024年第11期977-994,共18页
Most studies on the human gut microbiome have focused on the bacterial fraction rather than fungal biomics,which as resulted in an incomplete understanding of the fungal microbiome.Recent advances in microbiota detect... Most studies on the human gut microbiome have focused on the bacterial fraction rather than fungal biomics,which as resulted in an incomplete understanding of the fungal microbiome.Recent advances in microbiota detection and next-generation sequencing technology have boosted an increase in research on fungi.Symbiotic fungi have become increasingly influential in health and disease and modulate various physiologic functions within the host.Fungal infections can result in high morbidity and mortality rates and are life-threatening in some immunocompromised patients.In addition to bacterial dysbiosis,alterations in fungal communities are important and have been linked to many diseases,including asthma,mental illness,and various cancers.When investigating cancer it is imperative to consider the role of fungi alongside viruses and bacteria.This review examined the impact of intestinal fungi and peri-tumor fungi on tumorigenesis,cancer progression,and response to anticancer therapies.The review highlights the specific involvement of some fungal species in cancers include digestive tract tumors such as colorectal,pancreatic,liver,and gastric cancers,as well as non-digestive tract tumors such as lung,melanoma,breast,and ovarian cancers.Furthermore,fungal mechanisms of action,including fungus-host recognition and immune regulation,biofilm formation,toxin and metabolite production in the tumor microenvironment,and the complex effects of fungus-bacteria interactions on tumorigenesis and development,highlight the significance of potential biomarkers in cancer diagnosis and treatment. 展开更多
关键词 Gut microbiota FUNGI INTRATUMORAL CANCER cancer treatment responsiveness Candida albicans
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科学传播的舞台管理与信息控制: MCN信息披露对信任的影响机制研究 被引量:1
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作者 杨正 冯韵 吴福仲 《全球传媒学刊》 CSSCI 2024年第6期114-134,共21页
随着短视频时代科学传播内容制作的专业化与精细化,科学家群体与MCN(Multi-Channel Network)机构联盟进行科学传播内容创作已经成为值得关注的趋势。但当公众感知到MCN参与科学传播的进程时,他们对科学传播者与科学传播内容的信任程度... 随着短视频时代科学传播内容制作的专业化与精细化,科学家群体与MCN(Multi-Channel Network)机构联盟进行科学传播内容创作已经成为值得关注的趋势。但当公众感知到MCN参与科学传播的进程时,他们对科学传播者与科学传播内容的信任程度是否会发生变化?基于科学传播的“舞台管理”与“信息控制”理论,本研究通过两组线上实验,分别探索了在“科学饮食”和“疫苗接种”两个话题情境下,MCN信息披露对于科学传播中公众信任的影响及权威感知与亲近感知的中介角色。结果一致表明,MCN信息披露显著负向影响受众对科学传播者和传播内容的信任程度。在“科学饮食”的情境中,亲近感知负向中介了这一效应,权威感知的中介效应不显著;在“疫苗接种”的情境中,亲近感知与权威感知的负向中介效应均显著。本研究为不同议题情境下短视频平台的科学传播实践提供了启示。 展开更多
关键词 科学传播 MCN信息披露 舞台管理 信息控制 短视频
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一起110 kV电缆GIS终端爆炸故障分析 被引量:2
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作者 张毅涛 朱广秀源 +4 位作者 李剑武 董生成 贾海龙 云峰 甘云峰 《青海电力》 2024年第S01期90-95,共6页
分析了一起110 kV电缆GIS终端爆炸故障,通过解体检查、合金分析和X射线检测等手段判断本次故障的主要原因是电缆GIS终端应力锥端部局部放电造成绝缘老化,泄漏电流增大发热,在放电和发热共同作用下应力锥和环氧套管结合面绝缘强度降低发... 分析了一起110 kV电缆GIS终端爆炸故障,通过解体检查、合金分析和X射线检测等手段判断本次故障的主要原因是电缆GIS终端应力锥端部局部放电造成绝缘老化,泄漏电流增大发热,在放电和发热共同作用下应力锥和环氧套管结合面绝缘强度降低发生闪络。 展开更多
关键词 电缆GIS终端 应力锥 局部放电 过热
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中心点控制技术在双轴四缸电液伺服试验机上的应用 被引量:1
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作者 何雨奇 孙勇 +4 位作者 云峰 李洪营 张宁含玉 周皓月 张国志 《工程与试验》 2024年第1期69-70,78,共3页
为准确地反映复杂加载路径下的材料性能,近年来专家学者不断探索双轴拉伸试验方法,其中包括十字形试样法,但因试样的特殊性,常规的电液伺服试验机无法满足其试验要求,本文使用双轴四缸电液伺服试验机来解决此问题。由于试验过程中需要... 为准确地反映复杂加载路径下的材料性能,近年来专家学者不断探索双轴拉伸试验方法,其中包括十字形试样法,但因试样的特殊性,常规的电液伺服试验机无法满足其试验要求,本文使用双轴四缸电液伺服试验机来解决此问题。由于试验过程中需要试样的中心位置固定,为此采用基于中心位置控制的方法,设计了双轴PID协调加载控制技术。经试验验证,双轴四缸试验机满足试样中心区偏移可控要求,确保加载的协调控制。 展开更多
关键词 双轴四缸 中心点控制 电液伺服试验机
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Quantifying peripapillary vessel density and retinal nerve fibre layer in type 1 diabetic children without clinically detectable retinopathy using OCTA
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作者 Ling Chen yun feng +2 位作者 Sha-Sha Zhang Yan-Fang Liu Ping Lin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期278-281,共4页
AIM:To quantify changes in radial peripapillary capillary vessel density(ppVD)and the peripapillary retinal nerve fiber layer(pRNFL)in children with type 1 diabetes without clinical diabetic retinopathy by optical coh... AIM:To quantify changes in radial peripapillary capillary vessel density(ppVD)and the peripapillary retinal nerve fiber layer(pRNFL)in children with type 1 diabetes without clinical diabetic retinopathy by optical coherence tomography angiography(OCTA),providing a basis for early retinopathy in children with type 1 diabetes.METHODS:This was a retrospective study.A total of 30 patients(3–14y)with type 1 diabetes without clinical diabetic retinopathy(NDR group)were included.A total of 30 age-matched healthy subjects were included as the normal control group(CON group).The HbA1c level in the last 3mo was measured once in the NDR group.The pRNFL thickness and ppVD were automatically measured,and the mean pRNFL and ppVD were calculated in the nasal,inferior,temporal,and superior quadrants.The changes in ppVD and pRNFL in the two groups were analyzed.RESULTS:Compared with CON group,the nasal and superior ppVDs decreased in the NDR group(all P<0.01).The thickness of the nasal pRNFL decreased significantly(P<0.01),while the inferior,temporal and superior pRNFLs slightly decreased but not significant in the NDR group(all P>0.05).Person and Spearman correlation analysis of ppVD and pRNFL thickness in each quadrant of the NDR group showed a positive correlation between nasal and superior(all P<0.01),while inferior and temporal had no significant correlation(all P>0.05).There was no significant correlation between the HbA1c level and ppVD and pRNFL in any quadrant(all P>0.05).There was no significant correlation between the course of diabetes mellitus and ppVD and pRNFL in any quadrant(all P>0.05).CONCLUSION:ppVD and pRNFL decrease in eyes of children with type 1 diabetes before clinically detectable retinopathy and OCTA is helpful for early monitoring. 展开更多
关键词 diabetic retinopathy CHILDREN peripapillary vessel density peripapillary retinal nerve fiber layer optical coherence tomography angiography
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高压燃油系统油管接头密封性能研究
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作者 贾小丽 云峰 +2 位作者 李丽萍 董伟杰 范立云 《船舶工程》 CSCD 北大核心 2024年第5期77-83,共7页
为了研究燃油系统油管接头密封性能的影响因素,以某柴油机高压油管接头为研究对象,借助Hypermesh及ANSYS软件建立高压油管接头密封的有限元模型。根据赫兹接触理论及vonMises应力计算,探究不同预紧力、不同轨压作用下高压油管接头密封... 为了研究燃油系统油管接头密封性能的影响因素,以某柴油机高压油管接头为研究对象,借助Hypermesh及ANSYS软件建立高压油管接头密封的有限元模型。根据赫兹接触理论及vonMises应力计算,探究不同预紧力、不同轨压作用下高压油管接头密封带宽度及最大等效塑性应变的变化规律。结果表明:密封带宽度、最大等效塑性应变与预紧力呈正相关,且最大等效塑性应变与预紧力变化呈三次方关系;密封带宽度与轨压呈负相关,而轨压对等效塑性应变影响不显著,该研究结果可为高压油管接头的安装设计及管接头预紧力的选择提供理论支撑。 展开更多
关键词 高压燃油系统 油管接头 密封带宽度 等效塑性应变 预紧力
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Screening and field application of microbial-flooding activator systems
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作者 Xiutian Yao Lipeng Gai +6 位作者 yun feng Runlin Zhao Yang Gao Yucui Zhang Chuanzhi Cui Jun Ma Zhongwei Wu 《Energy Geoscience》 EI 2024年第2期14-20,共7页
This study aims to further enhance the oil recovery of reservoirs in the Zhong-2 Block of the Gudao Oilfield by identifying the most effective microbial-flooding activator systems and applying them in the field.We beg... This study aims to further enhance the oil recovery of reservoirs in the Zhong-2 Block of the Gudao Oilfield by identifying the most effective microbial-flooding activator systems and applying them in the field.We began by analyzing the structure of the reservoirs'endogenous microbial communities to understand the potential impact of microbial flooding.This was followed by determining commonly used activator systems based on their abilities to stimulate oil-displacement functional bacteria.Through laboratory experiments on oil displacement efficiency and sweep characteristics,we determined the optimal activator injection method(injection ratio)and the requisite bacterial concentration for maximal microbial-flooding efficacy.Finally,we selected the optimal activator systems and applied them to field tests.Our findings suggest the target block is highly receptive to microbial-flooding.In terms of performance,the activator systems ranked as No.3>No.4>No.1>No.2.Interestingly,a deep activator system,when compared to the top-performing No.3 system,exhibited a higher bacterial concentration peak and longer peaking duration.Optimal oil displacement effects were observed at a 1:4 vol ratio between the No.3 activator and deep activator systems,with bacterial concentrations of up to 106 cells/mL or above.Field tests with the selected activator systems,following a specific injection protocol,demonstrated a notable increase in oil production and a reduction in water cut. 展开更多
关键词 Zhong-2 Block of Gudao Oilfield Microbial flooding Laboratory experiment Screening of activator system Field application
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鼻内镜下低温等离子技术在鼻前庭囊肿治疗中的应用 被引量:19
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作者 刘津 冯云 +1 位作者 覃继新 黄焕来 《中国内镜杂志》 北大核心 2017年第7期6-10,共5页
目的比较鼻内镜辅助下低温等离子技术与传统唇龈沟入路在鼻前庭囊肿手术中的疗效。方法收集2013年1月-2016年11月在右江民族医学院附属医院耳鼻咽喉头颈外科收住的鼻前庭囊肿患者共38例,分为对照组20例和实验组18例,对照组采用唇龈沟入... 目的比较鼻内镜辅助下低温等离子技术与传统唇龈沟入路在鼻前庭囊肿手术中的疗效。方法收集2013年1月-2016年11月在右江民族医学院附属医院耳鼻咽喉头颈外科收住的鼻前庭囊肿患者共38例,分为对照组20例和实验组18例,对照组采用唇龈沟入路手术,实验组采用鼻内镜辅助下低温等离子消融,比较两组患者手术时间、术中出血量、术后住院时间、术后并发症以及复发情况等。结果实验组与对照组比较,平均手术时间减少[(65.45±27.51)vs(34.72±17.61)min,P=0.000]、术中出血量减少[(22.35±18.41)vs(3.17±1.69)ml,P=0.000]、术后住院时间缩短[(6.35±0.75)vs(3.61±1.19)d,P=0.000]和术后并发症减少(16 vs 1,P=0.000),两组复发情况差异无统计学意义(1 vs 0,P=0.783)。结论鼻内镜辅助下低温等离子技术治疗鼻前庭囊肿相对于传统唇龈沟入路,具有时间短、创伤小、恢复快、操作简单和疗效好的优势,值得推广。 展开更多
关键词 鼻前庭囊肿 鼻内镜 低温等离子
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