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Sensitivity of two drug-resistant bacteria to low-temperature air plasma in catheterassociated urinary tract infections under different environments 被引量:1
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作者 何媛媛 丁呈彪 +5 位作者 金涛 范玥瑶 吴征威 孙梦雯 王琨 纪拓 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第6期137-143,共7页
The high incidence of catheter-associated urinary tract infections,which are dominated by drugresistant bacteria,has attracted an increasing number of researchers interested in solving this public health problem.The p... The high incidence of catheter-associated urinary tract infections,which are dominated by drugresistant bacteria,has attracted an increasing number of researchers interested in solving this public health problem.The purpose of this study was to explore the killing effect of lowtemperature air plasma(LTAP)on extended-spectrum beta-lactamase-producing Escherichia coli and high level gentamycin resistance enterococci under two simulated environments in vitro.The results showed that the survival rate of these two kinds of bacteria decreased to less than20%after being treated by LTAP in different environments for 5 min.A comparison of the LTAP treatments showed that the killing efficacy of the two kinds of bacteria in the early stage(0-1 min)was up to 50%.Moreover,the results of transmission electron microscopy,reactive nitrogen species measurement,and a temperature test indicated that the bactericidal effect of the LTAP treatment on the two kinds of bacteria worked through the destruction of the ribosome and other organelles inside the bacteria,rather than the thermal effect,to achieve sterilization. 展开更多
关键词 CAUTI low-temperature air plasma ANTIBACTERIAL transmission electron microscopy
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聚二甲基硅氧烷-水性聚氨酯的合成与性能 被引量:5
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作者 张凡军 张玲玉 +3 位作者 贺媛媛 罗锋 李洁华 谭鸿 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第7期41-47,共7页
为了提高水性聚氨酯的耐水性和耐候性,文中以羟烷基聚二甲基硅氧烷(PDMS)和聚己二酸丁二醇酯二醇(PBA)为混合软段,间苯二亚甲基二异氰酸酯(XDI)和1,4-丁二醇(BDO)、二羟甲基丙酸(DMPA)为硬段,采用二步本体法合成一系列的聚二甲基硅氧烷... 为了提高水性聚氨酯的耐水性和耐候性,文中以羟烷基聚二甲基硅氧烷(PDMS)和聚己二酸丁二醇酯二醇(PBA)为混合软段,间苯二亚甲基二异氰酸酯(XDI)和1,4-丁二醇(BDO)、二羟甲基丙酸(DMPA)为硬段,采用二步本体法合成一系列的聚二甲基硅氧烷-水性聚氨酯(Si-XWPUs),研究了PDMS在软段中的含量对水性聚氨酯的表面性能、力学性能和耐水性的影响。研究发现,随着PDMS在软段中的含量从0%到20%逐渐增加,Si-XWPUs的微相分离程度略有提高,拉伸强度均达到10 MPa以上,作为涂层材料均具有较好的力学性能。同时,随PDMS在软段中比例的升高,Si-XWPUs薄膜表面Si元素的百分比呈增加趋势,并且表面的Si/C含量远远高于本体中理论Si/C含量,最高的迁移率达24倍,表现出良好的疏水性,同时吸水率降低。 展开更多
关键词 水性聚氨酯 聚二甲基硅氧烷 耐水性
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跨文化交际体验中的中国文化身份认同:对中国大学生的中国文化观的话语分析 被引量:1
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作者 和媛媛 肖琳 《Chinese Journal of Applied Linguistics》 2021年第2期219-240,264,共23页
本研究调查了一组中国大学生对“中国文化”的认知,考察了他们使用哪些话语为“中国文化”赋义,以及他们如何运用这些话语来建构其中国文化身份认同。研究者采用定性研究的方法,收集了北京某高校39名大学生关于关键性跨文化交际事件的... 本研究调查了一组中国大学生对“中国文化”的认知,考察了他们使用哪些话语为“中国文化”赋义,以及他们如何运用这些话语来建构其中国文化身份认同。研究者采用定性研究的方法,收集了北京某高校39名大学生关于关键性跨文化交际事件的反思报告。在反思报告中,这些大学生描述了以往跨文化交际经历中那些令他们产生强烈的中国文化身份认同感的事件,剖析了促使他们产生这一感受的中国文化要素。对反思报告的话语分析揭示了大学生对“中国文化”理解方式的多样性和流动性。研究结果对于我们认识当代大学生的中国文化身份认同及其备受争议的“文化身份认同危机”具有重要意义。 展开更多
关键词 中国文化身份认同 中国大学生 跨文化交际 社会建构主义 话语
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中成药辅助治疗对冠心病心绞痛患者主要不良心血管事件的影响:一项基于人群的回顾性队列研究
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作者 刘昳佳 李珠 +5 位作者 王旭 倪彤瑶 马梅 何媛媛 杨蓉蓉 雒明池 《Acupuncture and Herbal Medicine》 2022年第2期109-117,共9页
目的:本研究旨在探讨中成药(CPM)在降低冠心病(CHD)心绞痛患者主要不良心血管事件(MACE)发生率和提高临床疗效方面的作用,为其临床辅助治疗提供依据。方法:将6家医院28517例冠心病心绞痛住院患者分为CPM组(n=11374)和非CPM组(n=17143),... 目的:本研究旨在探讨中成药(CPM)在降低冠心病(CHD)心绞痛患者主要不良心血管事件(MACE)发生率和提高临床疗效方面的作用,为其临床辅助治疗提供依据。方法:将6家医院28517例冠心病心绞痛住院患者分为CPM组(n=11374)和非CPM组(n=17143),评估MACE的发生率,包括心肌梗死、经皮冠状动脉介入治疗、冠状动脉搭桥术。结果:CPM组MACE发生率低于非CPM组。CPM治疗是降低MACE总体风险的独立保护因素[HR=0.40,95%CI(0.33;0.49)]。CPM组中接受一种、两种或三种CPM的患者可以从CPM的辅助治疗中受益,并且服用更多类型的CPM与较低的MACE风险相关。此外,男性人群服用CPM优于女性,55-64岁的中年人更适合在西药基础上服用CPM。结论:CPM作为辅助治疗可降低冠心病心绞痛患者尤其是男性和中年人群MACE的发生,应优化相应药物治疗方案。然而,这一结论未来还需通过前瞻性队列研究进一步验证。 展开更多
关键词 中成药 冠心病心绞痛 主要心血管不良事件 回顾性队列研究
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Combination of photodynamic therapy and stimulator of interferon genes(STING)agonist inhibits colorectal tumor growth and recurrence
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作者 Yang Hao Sen Ma +7 位作者 Zili Gu Alireza Haghparast Timo Schomann Zhenfeng Yu yuanyuan he Xiaoxv Dong Luis J Cruz Peter ten Dijke 《Cancer Communications》 SCIE 2023年第4期513-518,共6页
Dear Editor,Great progress has been made in the clinical use of photodynamic therapy(PDT)for the treatment of patients with superficial tumors[1].However,cancer recurrence and metastasis have limited the application o... Dear Editor,Great progress has been made in the clinical use of photodynamic therapy(PDT)for the treatment of patients with superficial tumors[1].However,cancer recurrence and metastasis have limited the application of PDT in the treatment of solid tumors and advanced cancers.In this context,combining PDT with other complementary immunotherapy regimens may overcome these limitations of PDT[2]. 展开更多
关键词 STIMULATOR SUPERFICIAL clinical
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Petrologic and geochemical characteristics of high-quality saline lacustrine source rocks in western Qaidam Basin 被引量:2
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作者 Bin Zhang yuanyuan he +3 位作者 Yan Chen Qingyang Meng Jiaxuan Huang Li Yuan 《Petroleum Research》 2018年第4期359-369,共11页
The main oil source in western Qaidam Basin is the Paleogene saline lacustrine source rocks.Traditionally,it was considered that these source rocks were characterized by low abundance and poor type of organic matter a... The main oil source in western Qaidam Basin is the Paleogene saline lacustrine source rocks.Traditionally,it was considered that these source rocks were characterized by low abundance and poor type of organic matter as well as limited oil generation potential,but this poor source rock condition was very inconsistent with good hydrocarbon exploration results.A previous study has just confirmed that this area develops high-quality source rocks,which is of great significance for recognizing potential of hydrocarbon resource and consolidating confidence to search large and medium-sized oil and gas fields in western Qaidam Basin.Based on fine geochemical analysis of source rocks,petrology,element geochemistry and organic geochemistry are applied to discuss development conditions of high-quality source rocks in this area.The results showed that the saline lacustrine sediments in western Qaidam Basin were deposited in relatively shallow and quiet water with relatively high salinity and low nutrient content;influenced by the drought and cold climate,the terrigenous supply of fresh water was limited,and few aquatic organisms were developed.Good preservation condition is favorable for rapid preservation of oil generating biomass(such as aquatic organisms),to form source rocks rich in hydrogen element with high soluble organic matter content;but relatively lower paleo-productivity makes organic matter abundance lower than that in the eastern saline lacustrine basins.The semi-deep lake,with relatively low salinity and abundant nutrients,is the most favorable are for development of high-quality source rocks;the source rocks have large thickness in the sedimentary depression areas,but due to high water salinity and far away from the provenance area,the water stratification was obvious,so it have moderate to high organic matter abundance. 展开更多
关键词 Saline lacustrine source rocks TOC Major and trace elements Biomarker Paleo-productivity Preservation condition Qaidam basin
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Working principle and application of photocatalytic optical fibers for the degradation and conversion of gaseous pollutants
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作者 Wenhao Xiang Jilin Yuan +6 位作者 Yongwu Wu Hongyang Luo Chuanbao Xiao Nianbing Zhong Mingfu Zhao Dengjie Zhong yuanyuan he 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第8期3632-3640,共9页
Photocatalytic optical fibers are promising for the degradation of gaseous and volatile pollutants in air due to their high specific surface area,high light utilization efficiency,easy regeneration,and sustainability.... Photocatalytic optical fibers are promising for the degradation of gaseous and volatile pollutants in air due to their high specific surface area,high light utilization efficiency,easy regeneration,and sustainability.In particular,photocatalytic optical fibers have proven highly useful for the removal and conversion of different kinds of air pollutants in air.However,these fibers suffer from low photocatalytic degradation efficiencies.In this review,we have focused on introducing photocatalytic quartz optical fibers and photocatalytic plastic optical fibers for the degradation and transformation of gas-phase air pollutants.The principle of photocatalytic optical fibers and main methods for improving their photocatalytic and light utilization efficiencies based on semiconductor photocatalytic coatings are summarized.Moreover,the Langmuir-Hinshelwood kinetic rate equation was summarized to analyze the photocatalytic reduction of gaseous pollutants.Finally,an outlook on the future of photocatalytic optical fibers toward the removal and conversion of gaseous air pollutants is discussed. 展开更多
关键词 Photocatalytic optical fibers Semiconductor photocatalysts Gaseous pollutant Photocatalytic activity Photocatalytic efficiency
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Aerodynamic analysis of insect-like flapping wings in fan-sweep and parallel motions with the slit effect
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作者 Zenggang Zhu Jingtai Zhao +3 位作者 yuanyuan he Shijun Guo Si Chen Bing Ji 《Biomimetic Intelligence & Robotics》 2022年第2期55-66,共12页
In this study,the aerodynamic performance of flapping wings using a parallel motion was investigated and compared with the insect-like‘‘fan-sweep’’motion,and the effect of adding a slit to the wings was analyzed.F... In this study,the aerodynamic performance of flapping wings using a parallel motion was investigated and compared with the insect-like‘‘fan-sweep’’motion,and the effect of adding a slit to the wings was analyzed.First,numerical simulations were performed to analyze the wing aerodynamics of two flapping motions with equivalent stroke amplitudes over a range of pitching angles based on computational fluid dynamics(CFD).The simulation results indicated that flapping wings with a rapid and short parallel motion achieved better lift and efficiency than those of the fan-sweep motion while maintaining the same aerodynamic characteristics regarding stall delay and leading-edge vortices.For a parallel motion with a pitching angle of 25◦and 100 mm stroke amplitude,the wings generated an average lift of 8.4 gf with a lift-to-drag ratio of 1.06,respectively,which were 1.8%and 26%greater than those of the fan-sweep motion with a corresponding 96◦stroke amplitude.This situation was reversed when the pitching angle and stroke amplitude were increased to 45◦and 144◦for the fan-sweep motion,which was equivalent to the parallel motion with a 150 mm stroke amplitude.The slit effect in the parallel motion was also evaluated,and the CFD results indicated that a slit width of 1 mm(1/50 wing chord)increased the lift of the wing by approximately 27%in the case of the 150 mm stroke amplitude.Further,the slit width slightly influenced the lift and aerodynamic efficiency. 展开更多
关键词 Insect-like flapping wings Aerodynamic efficiency Fan-sweep Parallel flapping motion Wing slit
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Lightnin内插件强化混合器内湍流混合及反应特性
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作者 禹言芳 贺媛媛 +3 位作者 杨鹏 姚云娟 孟辉波 吴剑华 《过程工程学报》 CAS CSCD 北大核心 2022年第12期1683-1690,共8页
采用计算流体力学组分输运模型和SST k-ω湍流模型,在Re=3000~9000范围内研究Lightnin静态混合器内萘酚(组分A)与对氨基苯磺酸(组分B)偶合氮化串联竞争反应,分析化学反应场中各组分浓度分布规律、湍流流动及微观混合特性。Lightnin内插... 采用计算流体力学组分输运模型和SST k-ω湍流模型,在Re=3000~9000范围内研究Lightnin静态混合器内萘酚(组分A)与对氨基苯磺酸(组分B)偶合氮化串联竞争反应,分析化学反应场中各组分浓度分布规律、湍流流动及微观混合特性。Lightnin内插件能够推进管内主反应的高效进行,副产物S较少且其浓度在0.0004~0.03 mol/L,而主产物R的浓度较副产物S高两个数量级。湍流强度随着雷诺数的增大呈现明显上升趋势,Re=3000时z/l=2处的湍流强度峰值(达到2.95)是出口处的2.02倍。湍流耗散率ε随径向位置的增加而减小,w_(A)=0.5~0.6时浓度对ε的影响微弱,而w_(A)=0.7~0.9时ε的轴向和径向分布随着浓度的增大逐渐减小,w_(A)=0.6~0.9时z/l=10处的ε相比于w_(A)=0.5时依次减小2.43%,8.86%,19.80%,42.25%。Re=6000~9000时径流数呈周期规律分布,偶数旋流元件内形成小峰值,奇数元件内则内凹。组分A与组分B在摩尔比一定的条件下,Re=4000~9000出口位置处的微观混合特性相比于Re=3000时分别增强18.22%~55.34%。 展开更多
关键词 Lightnin内插件 组分输运模型 串联竞争反应 径流数 离集指数
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Depression and stress levels increase risk of liver cancer through epigenetic downregulation of hypocretin 被引量:2
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作者 Chunyun Pu Shaorong Tian +9 位作者 Sanxiu he Weihong Chen yuanyuan he Hongyan Ren Jing Zhu Jun Tang Xiaolan Huang Ying Xiang Yixiao Fu Tingxiu Xiang 《Genes & Diseases》 SCIE 2022年第4期1024-1037,共14页
Recent studies suggest that Hypocretin (HCRT, Orexin) are involved in stress regulation of depression through the hypothalamic-pituitary-adrenal (HPA) axis. However, the molecular mechanism by which Hypocretin regulat... Recent studies suggest that Hypocretin (HCRT, Orexin) are involved in stress regulation of depression through the hypothalamic-pituitary-adrenal (HPA) axis. However, the molecular mechanism by which Hypocretin regulate neurobiological responses is unknown. Herein, the effects of chronic stress on the epigenetic modification of HCRT and its association with depression were explored with regard to a potential role in cancer progression. In the study, Sprague Dawley (SD) rats were used to establish an animal model of cancer with depression by administrating n-nitrosodiethylamine (DEN) and chronic unpredictable mild stress (CUMS). RNA-sequencing was used to detect differentially expressed genes in the hippocampus of rats and quantitative real-time polymerase chain reaction (qRT-PCR) was used to validate the results of RNA-sequencing. The status of HCRT promoter methylation was assessed by methylation specific polymerase chain reaction. Behavioral tests showed that rats exposed to CUMS had significant depressive-like behaviors. The number of liver tumors and tumor load in depressed rats exposed to CUMS was higher than in SD rats without CUMS. RNA-sequencing revealed that HCRT was one of the most siginificantly downregulated gene in the hippocampus of SD rats with CUMS compared to non-stressed group, which was validated by qRT-PCR. HCRT mRNA expression was downregulated and the promoter for HCRT was hyper-methylated in those with depression. These results identified a critical role for chronic psychological stressors in tumorigenesis and cancer progression, via epigenetic HCRT downregulation. Such epigenetic downregulation may be the molecular basis for the association of cancer with depression. 展开更多
关键词 Cancer Chronic unpredictability mild stress CpG methylation Depressi on HYPOCRETIN
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