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溴甲烷熏蒸对土壤反硝化作用及nosZ型反硝化微生物群落结构的影响 被引量:5
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作者 燕平梅 乔宏萍 +3 位作者 赵文婧 陈燕飞 单树花 曹坳程 《微生物学报》 CAS CSCD 北大核心 2015年第1期73-79,共7页
【目的】探究溴甲烷熏蒸对土壤反硝化作用的影响及机制。【方法】本研究采用nos Z-PCR-RFLP(Restriction fragment length polymorphism)方法、nos Z-MPN-PCR(Most-Probable-Number-PCR)计数法和土壤硝酸根的消灭率方法研究溴甲烷熏蒸... 【目的】探究溴甲烷熏蒸对土壤反硝化作用的影响及机制。【方法】本研究采用nos Z-PCR-RFLP(Restriction fragment length polymorphism)方法、nos Z-MPN-PCR(Most-Probable-Number-PCR)计数法和土壤硝酸根的消灭率方法研究溴甲烷熏蒸对土壤nos Z型反硝化细菌群落结构、数量及反硝化活性的影响。【结果】实验结果说明溴甲烷熏蒸剂熏蒸土壤100 d土壤的反硝化作用与对照无显著差异(P>0.05)。溴甲烷熏蒸土壤和对照土样nos Z型反硝化细菌群落的Margalef指数,Shannon-Wiener和Evenness指数无显著差异(P>0.05)。溴甲烷熏蒸土壤和对照土壤中存在Uncultured bacterium partial rhodopsendomonas、pseudomonas fluorescens、Herbacspirillum、Mesorhizobium和Bradyrhizobium,并且此6种微生物均是试验土样和对照土样的优势种群;对照土壤中检测到Azospirillum、Rhizobium melibei和Nitrosospira multiformis,在溴甲烷熏蒸土壤中未检测到;而溴甲烷熏蒸土壤中检测到Uncultured Azospirillum,Mesorhizobium在对照土壤中未检测到。通过nos Z-MPN-PCR计数法得出反硝化细菌数量比对照低1.4倍。【结论】说明溴甲烷熏蒸100d土壤的nos Z型反硝化微生物群落组成和反硝化细菌数量发生变化,而土壤的反硝化作用与对照无显著差异。 展开更多
关键词 溴甲烷 熏蒸 反硝化细菌 nosZ基因 群落结构
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Thyroid Hormones in Prostate Cancer:A Systematic Review and Bibliometric Study
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作者 Jinhai Wu Xuejin Zhu +2 位作者 yanfei chen Jing Li Bin Wang 《Proceedings of Anticancer Research》 2025年第5期16-27,共12页
Prostate cancer(PCa)is a prevalent malignancy in men,traditionally linked to androgen receptor signaling.Emerging evidence suggests thyroid hormones(THs,particularly T3/T4)play a complex role in PCa biology.THs regula... Prostate cancer(PCa)is a prevalent malignancy in men,traditionally linked to androgen receptor signaling.Emerging evidence suggests thyroid hormones(THs,particularly T3/T4)play a complex role in PCa biology.THs regulate gene transcription via nuclear receptors TRα/β,modulating proliferation,apoptosis,and AR signaling,while non-genomic pathways through integrin αvβ3 activate MAPK/PI3K-Akt signaling,driving metabolic reprogramming,migration,and angiogenesis.Local DIO enzymes fine-tune T3/T4 levels,with DIO2 enhancing proliferation and DIO3 creating a low-TH microenvironment to facilitate immune evasion.Epidemiological studies associate hyperthyroidism or low TSH with elevated PCa risk,whereas experimental models show inconsistent effects,reflecting regulation by hormone levels,receptor distribution,and tumor molecular features.Bibliometric analyses reveal a shift from epidemiological studies to molecular,immune,and metabolic mechanistic research,though clinical translation remains limited.This review synthesizes current knowledge on THs in PCa,highlighting mechanistic insights,evidence gaps,and future directions,aiming to inform early detection,stratification,and therapeutic strategies. 展开更多
关键词 Prostate cancer Thyroid hormones BIBLIOMETRICS CITESPACE VOSviewer
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1-丁基-3-甲基咪唑四氟硼酸盐改性淀粉/聚丁二酸丁二醇酯共混材料的结构与性能 被引量:2
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作者 杨召杰 徐进 +2 位作者 陈彦霏 梁兵 张熙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第1期134-140,共7页
以离子液体1-丁基-3-甲基咪唑四氟硼酸盐([BMIM]BF_(4))为改性剂,分别采用玉米淀粉(S)、羧甲基淀粉(CMS)和羟丙基淀粉(HPS)制备了淀粉/聚丁二酸丁二醇酯(PBS)共混材料,利用红外光谱、扫描电镜、X射线衍射、热重分析、差式扫描量热分析... 以离子液体1-丁基-3-甲基咪唑四氟硼酸盐([BMIM]BF_(4))为改性剂,分别采用玉米淀粉(S)、羧甲基淀粉(CMS)和羟丙基淀粉(HPS)制备了淀粉/聚丁二酸丁二醇酯(PBS)共混材料,利用红外光谱、扫描电镜、X射线衍射、热重分析、差式扫描量热分析及力学性能测试等方法研究了共混材料的结构与性能。结果表明,[BMIM]BF_(4)可破坏淀粉的原有氢键,降低淀粉/PBS的结晶度、提高淀粉与PBS的相容性。[BMIM]BF_(4)对采用不同结构淀粉制备的淀粉/PBS共混材料作用效果不同,淀粉中取代基的空间位阻及静电斥力有利于提高[BMIM]BF_(4)与大分子的相互作用,使[BMIM]BF_(4)的改性作用增强。[BMIM]BF_(4)对采用不同结构淀粉制备的淀粉/PBS共混材料改性作用强度为:CMS/PBS>HPS/PBS>S/PBS。在所研究的淀粉/PBS共混材料中,[BMIM]BF_(4)与CMS/PBS共混体系的相互作用最强,体系相容性最好,共混材料的断裂伸长率最高,韧性最好。 展开更多
关键词 聚丁二酸丁二醇酯 玉米淀粉 羟丙基淀粉 羧甲基淀粉 1-丁基-3-甲基咪唑四氟硼酸盐 共混材料
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甘油/1-丁基-3-甲基咪唑氯盐改性玉米淀粉/聚丁二酸丁二醇酯共混材料的结构与性能 被引量:6
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作者 陈彦霏 丁康 +1 位作者 杨召杰 张熙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第6期40-45,55,共7页
为提高淀粉/聚丁二酸丁二醇酯(PBS)共混材料的相容性和力学性能,以甘油和1-丁基-3-甲基咪唑氯盐([BMIM]C1)复配作为改性剂,通过熔融共混法制备了玉米淀粉/PBS共混材料;采用红外光谱、X射线衍射分析、扫描电镜、差示扫描量热法及力学性... 为提高淀粉/聚丁二酸丁二醇酯(PBS)共混材料的相容性和力学性能,以甘油和1-丁基-3-甲基咪唑氯盐([BMIM]C1)复配作为改性剂,通过熔融共混法制备了玉米淀粉/PBS共混材料;采用红外光谱、X射线衍射分析、扫描电镜、差示扫描量热法及力学性能测试等方法研究了复配改性剂对淀粉/PBS共混材料结构和性能的影响。结果表明,该复配增塑剂对玉米淀粉/PBS有良好的改性作用,改性效果与组成配比有关,随着改性剂中[BMIM]Cl含量的增加,改性淀粉/PBS的断裂伸长率逐渐增大,当[BMIM]Cl与甘油的质量比为9:1时,共混材料的断裂伸长率最高,表现出比甘油或[BMIM]Cl更强的改性作用。甘油/[BMIM]Cl主要通过改变羟基的氢键、增强淀粉-改性剂-PBS分子间的作用实现改性,能提高淀粉与PBS的相容性,降低共混材料的结晶度,可在共混材料拉伸强度变化不大的条件下,显著提高共混材料的断裂伸长率。以甘油/[BMIM]Cl(质量比9:1,加量为淀粉质量35%)为改性剂制备的淀粉/PBS共混材料(淀粉占淀粉与PBS的总质量的40%)的拉伸强度为17.53 MPa、断裂伸长率可达211.50%。 展开更多
关键词 聚丁二酸丁二醇酯 玉米淀粉 1-丁基-3-甲基咪唑氯盐 甘油 共混材料
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HPMC/P(AM-co-AA)-Zr^(4+)/NaCl导电水凝胶的制备与性能 被引量:4
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作者 张甲樋 杜文浩 +1 位作者 陈彦霏 张熙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第8期1-8,17,共9页
为制备具有良好力学性能和导电性能的水凝胶,在羟丙基甲基纤维素(HPMC)存在的条件下,以丙烯酰胺(AM)和丙烯酸(AA)为共聚单体、Zr^(4+)为交联剂,通过原位自由基聚合制备了HPMC/P(AM-co-AA)-Zr^(4+)/NaCl双网络水凝胶,并对其力学性能、导... 为制备具有良好力学性能和导电性能的水凝胶,在羟丙基甲基纤维素(HPMC)存在的条件下,以丙烯酰胺(AM)和丙烯酸(AA)为共聚单体、Zr^(4+)为交联剂,通过原位自由基聚合制备了HPMC/P(AM-co-AA)-Zr^(4+)/NaCl双网络水凝胶,并对其力学性能、导电性能及相关传感性能进行了研究。结果表明,所制备的HPMC/P(AM-co-AA)-Zr^(4+)/NaCl水凝胶断裂应变达1820%、断裂强度为0.77 MPa、断裂能为4210 kJ/m^(3),电导率为8.44 S/m,可实现力学性能与导电性能的平衡。该水凝胶具有良好的回复能力和较高应变灵敏度,表现出宽的应变窗口(0%~800%),可望用于应变传感器。 展开更多
关键词 羟丙基甲基纤维素 丙烯酰胺-丙烯酸共聚物 导电水凝胶 力学性能 导电性能 应变传感器
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Recanalization of extracranial internal carotid artery occlusion A 12-year retrospective study 被引量:21
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作者 Liqun Jiao Gang Song +4 位作者 Yang Hua Yan Ma yanfei chen Yabing Wang Feng Ling 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第23期2204-2206,共3页
This study aimed to summarize therapy experience of carotid endarterectomy, carotid endarterec- tomy combined with Fogarty catheter embolectomy, and hybrid surgery for the treatment of extrac- ranial internal carotid ... This study aimed to summarize therapy experience of carotid endarterectomy, carotid endarterec- tomy combined with Fogarty catheter embolectomy, and hybrid surgery for the treatment of extrac- ranial internal carotid artery occlusion. The study included 65 patients with extracranial internal ca- rotid artery occlusion who underwent carotid endarterectomy, carotid endarterectomy combined with Fogarty catheter embotectomy, or hybrid surgery in the Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China between January 2006 and December 2012. Prior to surgery, all patients underwent perfusion CT or xenon CT to evaluate the occlusion. The procedure for each patient was chosen according to digital subtraction angiography data. The carotid artery was successfully recanalized in 46 of 51 patients who underwent carotid endarterectomy, 9 of 10 patients who underwent carotid endarterectomy combined with Fogarty catheter embolectomy, and 3 of 4 patients who underwent hybrid surgery. In patients with symptomatic carotid artery occlusion, the carotid artery can be recanalized by choosing a treatment procedure based on imaging ex- amination findings. 展开更多
关键词 neural regeneration carotid occlusion CAROTID carotid artery stenting carotid endarterectorny RECANALIZATION retrospective study grants-supported paper NEUROREGENERATION
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利用深度学习系统筛查新冠病毒肺炎 被引量:22
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作者 徐小微 蒋贤高 +18 位作者 马春莲 杜鹏 李旭坤 吕双志 俞亮 倪勤 陈燕飞 苏俊威 郎观晶 李永涛 赵宏 刘俊 徐凯进 阮凌翔 盛吉芳 裘云庆 吴炜 梁廷波 李兰娟 《Engineering》 SCIE EI 2020年第10期1266-1274,共9页
实时逆转录聚合酶链反应(RT-PCR)检测早期新冠病毒肺炎(COVID-19)患者的痰液或鼻咽拭子中的病毒RNA阳性率较低。同时,COVID-19的计算机断层扫描(CT)影像学的临床表现有其自身的特点,不同于甲型流感病毒性肺炎(IAVP)等其他类型的病毒性... 实时逆转录聚合酶链反应(RT-PCR)检测早期新冠病毒肺炎(COVID-19)患者的痰液或鼻咽拭子中的病毒RNA阳性率较低。同时,COVID-19的计算机断层扫描(CT)影像学的临床表现有其自身的特点,不同于甲型流感病毒性肺炎(IAVP)等其他类型的病毒性肺炎。本研究旨在应用深度学习技术,建立COVID-19、IAVP及健康人群肺部CT的早期筛查模型。本研究共采集618份CT样本,其中219份样本来自110例COVID-19患者(平均年龄50岁,其中男性63例,占57.3%),224份样本来自224例IAVP患者(平均年龄61岁,其中男性156例,占69.6%),175份样本来自健康人群(平均年龄39岁,其中男性97例,占55.4%)。所有CT样本均来自浙江省三家COVID-19定点收治医院。我们首先利用胸部CT图像集的三维(3D)深度学习模型分割出候选感染区域,然后利用位置敏感机制深度学习网络将这些分离的图像归类为COVID-19、IAVP以及与感染无关(ITI)的图像,并且输出相应置信度得分。最后,用Noisy-OR贝叶斯函数计算每份CT病例的感染类型及总置信度。测试数据集的实验结果表明,从整体CT病例来看,本研究利用深度学习系统建立的COVID-19患者的早期筛查模型的总体准确率为86.7%。该模型有望成为一线临床医生诊断COVID-19的一种有效的辅助方法。 展开更多
关键词 COVID-19 位置敏感机制深度学习网络 计算机断层扫描
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Review on mechanics of ultra-high-temperature materials 被引量:6
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作者 Daining Fang Weiguo Li +4 位作者 Tianbao cheng Zhaoliang Qu yanfei chen Ruzhuan Wang Shigang Ai 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2021年第9期1347-1370,I0001,共25页
Ultra-high-temperature materials have applications in aerospace and nuclear industry.They are usually subjected to complex thermal environments during service.The mechanical properties of materials in ultra-high-tempe... Ultra-high-temperature materials have applications in aerospace and nuclear industry.They are usually subjected to complex thermal environments during service.The mechanical properties of materials in ultra-high-temperature environments have been attracted increasing attentions.However,the characterization and evaluation of ultra-high-temperature mechanical properties of materials are still challenging work.This article presents a review on the mechanical properties of materials at elevated temperatures.The experimental results and techniques on the ultra-high-temperature mechanical properties of materials are reviewed.The constitutive models of materials at elevated temperatures are discussed.The recent research progress on the quantitative theoretical characterization models for the temperature-dependent fracture strength of advanced ceramics and their composites is also given,and the emphasis is placed on the applications of the force-heat equivalence energy density principle.The thermal–mechanical-oxygen coupled computational mechanics of materials are discussed.Furthermore,the outlook and concluding remarks are highlighted. 展开更多
关键词 Ultra-high-temperature materials Mechanical properties Mechanical testing Theoretical characterization Numerical simulation
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Simulating the Spreading of Two Competing Public Opinion Information on Complex Network 被引量:9
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作者 Mengshu Xie Zhen Jia +1 位作者 yanfei chen Qixiang Deng 《Applied Mathematics》 2012年第9期1074-1078,共5页
In this paper, we investigate the regularity of spreading of information and public opinions towards two competing products in complex networks. By building its mathematical model and simulating its evolution process,... In this paper, we investigate the regularity of spreading of information and public opinions towards two competing products in complex networks. By building its mathematical model and simulating its evolution process, we have found the statistical regularity for support rates of two different products at a steady stage. The research shows that strength of the public opinion spreading is proportional to the final support rates of a product. 展开更多
关键词 COMPLEX Network PUBLIC OPINION INFORMATION Competing SPREADING
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An improved particle filter indoor fusion positioning approach based on Wi-Fi/PDR/geomagnetic field 被引量:2
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作者 Tianfa Wang Litao Han +5 位作者 Qiaoli Kong Zeyu Li Changsong Li Jingwei Han Qi Bai yanfei chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期443-458,共16页
The existing indoor fusion positioning methods based on Pedestrian Dead Reckoning(PDR)and geomagnetic technology have the problems of large initial position error,low sensor accuracy,and geomagnetic mismatch.In this s... The existing indoor fusion positioning methods based on Pedestrian Dead Reckoning(PDR)and geomagnetic technology have the problems of large initial position error,low sensor accuracy,and geomagnetic mismatch.In this study,a novel indoor fusion positioning approach based on the improved particle filter algorithm by geomagnetic iterative matching is proposed,where Wi-Fi,PDR,and geomagnetic signals are integrated to improve indoor positioning performances.One important contribution is that geomagnetic iterative matching is firstly proposed based on the particle filter algorithm.During the positioning process,an iterative window and a constraint window are introduced to limit the particle generation range and the geomagnetic matching range respectively.The position is corrected several times based on geomagnetic iterative matching in the location correction stage when the pedestrian movement is detected,which made up for the shortage of only one time of geomagnetic correction in the existing particle filter algorithm.In addition,this study also proposes a real-time step detection algorithm based on multi-threshold constraints to judge whether pedestrians are moving,which satisfies the real-time requirement of our fusion positioning approach.Through experimental verification,the average positioning accuracy of the proposed approach reaches 1.59 m,which improves 33.2%compared with the existing particle filter fusion positioning algorithms. 展开更多
关键词 Fusion positioning Particle filter Geomagnetic iterative matching Iterative window Constraint window
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Polar motion prediction using the combination of SSA and ARMA 被引量:2
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作者 Qiaoli Kong Jingwei Han +4 位作者 Xin Jin Changsong Li Tianfa Wang Qi Bai yanfei chen 《Geodesy and Geodynamics》 EI CSCD 2023年第4期368-376,共9页
High-precision polar motion(PM) prediction is of important significance in astronomy, geodesy, aviation,hydrographic mapping, interstellar navigation, and so on. SSA can effectively extract the trend and period terms ... High-precision polar motion(PM) prediction is of important significance in astronomy, geodesy, aviation,hydrographic mapping, interstellar navigation, and so on. SSA can effectively extract the trend and period terms of PM,in the process of achieving high-precision medium-and long-term polar motion prediction,it is necessary to solve the end effect problem and overfitting problem of SSA forecasting method;therefore, ARMA was applied to decreasethe end effect, and a suitable combination of reconstructed components was determined to avoid the high variance reaction of SSA overfitting. Based on the decomposition and reconstruction of the PM by SSA, the reconstructed components are determined to participate in the SSA iterative fitting model according to the variance contribution rate. The combination of the reconstructed components representing the polar motion period term and the trend term is determined according to the correlation analysis of the selected reconstructed components. After the above work, the principal component prediction sequence is obtained by fitting the period term and the trend term to convergence, respectively, and then, the SSA end effect is modified, and the residual term is predicted based on ARMA. The test results show that he prediction accuracy of SSA + ARMA at the front of the X and Y directions are improved by 96.90% and 97.53% compared with those of SSA, respectively,and the forecast accuracy of 365 days are improved by 37.93% and 19.53% in the X and Y directions compared with those of Bulletin A, respectively. 展开更多
关键词 Polar motion prediction SSA ARMA End effect
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Surface ozone in global cities:A synthesis of basic features,exposure risk,and leading meteorological driving factors 被引量:2
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作者 Jinmian Ni Jiming Jin +6 位作者 Yanwen Wang Bin Li Qian Wu yanfei chen Shenwen Du Yilin Li Chao He 《Geography and Sustainability》 CSCD 2024年第1期64-76,共13页
Long-term exposure to high surface ozone(O_(3))concentrations,a complex oxidative atmospheric pollutant,can adversely impact human health.Based on O_(3)monitoring data from 261 cities worldwide in 2020,generalized add... Long-term exposure to high surface ozone(O_(3))concentrations,a complex oxidative atmospheric pollutant,can adversely impact human health.Based on O_(3)monitoring data from 261 cities worldwide in 2020,generalized additive model(GAM)and spatial data analysis(SDA)methods were applied in this study to quantitatively evaluate the spatiotemporal distribution of O_(3)concentration,exposure risk,and dominant meteorological factors.Results indicated that over 40%of the cities worldwide were exposed to harmful O_(3)concentration ranges(40-60μg/m^(3)),with most cities distributed in China and India.Moreover,significant seasonal variations in global O_(3)concentrations were observed,presenting as summer(45.6μg/m^(3))>spring(47.3μg/m^(3))>autumn(38.0μg/m^(3))>winter(33.6μg/m^(3)).Exposure analysis revealed that approximately 12.2%of the population in 261 cities were exposed to an environment with high O_(3)concentrations(80-160μg/m^(3)),with about 36.32 million people in major countries.Thus,the persistent increase in high O_(3)levels worldwide is a critical factor contributing to threats to human health.Furthermore,GAM results indicated temperature,relative humidity,and wind speed as primary determinants of O_(3)variability.The synergy of meteorological factors is critical for understanding O_(3)changes.Our findings are important for enforcing robust air quality policies and mitigating public risk. 展开更多
关键词 Ozone pollution Spatiotemporal variation Exposure risk GAM Meteorological factors
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Identification of Monocytes Associated with Severe COVID-19 in the PBMCs of Severely Infected Patients Through Single-Cell Transcriptome Sequencing 被引量:1
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作者 Yan Zhang Shuting Wang +9 位作者 He Xia Jing Guo Kangxin He chenjie Huang Rui Luo yanfei chen Kaijin Xu Hainv Gao Jifang Sheng Lanjuan Li 《Engineering》 SCIE EI CAS 2022年第10期161-169,共9页
Understanding the immunological characteristics of monocytes-including the characteristics associated with fibrosis-in severe coronavirus disease 2019(COVID-19)is crucial for understanding the pathogenic mechanism of ... Understanding the immunological characteristics of monocytes-including the characteristics associated with fibrosis-in severe coronavirus disease 2019(COVID-19)is crucial for understanding the pathogenic mechanism of the disease and preventing disease severity.In this study,we performed single-cell transcriptomic sequencing of peripheral blood samples collected from six healthy controls and 14 COVID-19samples including severe,moderate,and convalescent samples from three severely/critically ill and four moderately ill patients.We found that the monocytes were strongly remodeled in the severely/critically ill patients with COVID-19,with an increased proportion of monocytes and seriously reduced diversity.In addition,we discovered two novel severe-disease-specific monocyte subsets:Mono 0 and Mono 5.These subsets expressed amphiregulin(AREG),epiregulin(EREG),and cytokine interleukin-18(IL-18)gene,exhibited an enriched erythroblastic leukemia viral oncogene homolog(ErbB)signaling pathway,and appeared to exhibit pro-fibrogenic and pro-inflammation characteristics.We also found metabolic changes in Mono 0 and Mono 5,including increased glycolysis/gluconeogenesis and an increased hypoxia inducible factor-1(HIF-1)signaling pathway.Notably,one pre-severe sample displayed a monocyte atlas similar to that of the severe/critical samples.In conclusion,our study discovered two novel severedisease-specific monocyte subsets as potential predictors and therapeutic targets for severe COVID-19.Overall,this study provides potential predictors for severe disease and therapeutic targets for COVID-19 and thus provides a resource for further studies on COVID-19. 展开更多
关键词 COVID-19 Severe infection Critically ill MONOCYTES FIBROSIS
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Adaptive Lag Synchronization of Lorenz Chaotic System with Uncertain Parameters 被引量:1
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作者 yanfei chen Zhen Jia Guangming Deng 《Applied Mathematics》 2012年第6期549-553,共5页
The paper discusses lag synchronization of Lorenz chaotic system with three uncertain parameters. Based on adaptive technique, the lag synchronization of Lorenz chaotic system is achieved by designing a novel nonlinea... The paper discusses lag synchronization of Lorenz chaotic system with three uncertain parameters. Based on adaptive technique, the lag synchronization of Lorenz chaotic system is achieved by designing a novel nonlinear controller. Furthermore, the parameters identification is realized simultaneously. A sufficient condition is given and proved theoreticcally by Lyapunov stability theory and LaSalle’s invariance principle. Finally, the numerical simulations are provided to show the effectiveness and feasibility of the proposed method. 展开更多
关键词 LAG Synchronization ADAPTIVE Technique UNCERTAIN Parameters LORENZ CHAOTIC System
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Characterization of the Gastric Mucosal Microbiota in Patients with Liver Cirrhosis and Its Associations with Gastrointestinal Symptoms
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作者 yanfei chen Jing Guo +4 位作者 Chunlei chen Ding Shi Daiqiong Fang Feng Ji Lanjuan Li 《Engineering》 SCIE EI 2021年第4期507-514,共8页
Several studies have indicated that the oral and gut microbiota may exhibit differences in patients with cirrhosis.Less is known about the microbiota in the stomach,which is located between the oral cavity and the int... Several studies have indicated that the oral and gut microbiota may exhibit differences in patients with cirrhosis.Less is known about the microbiota in the stomach,which is located between the oral cavity and the intestinal tract.In this study,the gastric mucosal microbiota of patients with liver cirrhosis and controls were analyzed with 16S ribosomal RNA(rRNA)pyrosequencing.Cirrhotic patients had significantly lower Helicobacter pylori(H.pylori)infection rates,as confirmed by both the histological method and the pyrosequencing method.In H.pylori-negative subjects,gastric bacterial communities of healthy and cirrhosis cohorts were clustered into four clusters based on bacterial compositions:Cluster_1 and Cluster_2(mostly cirrhosis),Cluster_3(mostly healthy),and Cluster_4(around half of each).Compositional and functional differences were observed among these different clusters.At the genus level,Cluster_1 and Cluster_2 showed enrichment of Neisseria and Streptococcus,respectively.Functionally,Cluster_2 was characterized as depleted of genetic information processing,as well as of modules related to glycan biosynthesis and metabolism.Patients in Cluster_2 had more severe gastrointestinal symptoms and a higher rate of previous endoscopic variceal ligation(EVL)therapy than patients in other clusters.Our findings suggest that the colonization of both H.pylori and non-H.pylori is influenced in liver cirrhosis.Although the H.pylori-negative gastric mucosal microbiota showed considerable heterogeneity,associations between specific gastric microbiota and clinical characteristics could be observed.Previous EVL therapy might lead to a distinct structure of the gastric mucosal microbiota,thus aggravating the gastrointestinal symptoms in H.pylori-negative cirrhotic patients. 展开更多
关键词 MICROBIOME Liver cirrhosis SYMPTOMS VARICES Gastric endoscopy
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Ultra-conservative noncoding RNA uc.243 confers chemo-resistance by facilitating the efflux of the chemotherapeutic drug in ovarian cancer
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作者 SHAN JIANG XIUFENG LIN +2 位作者 yanfei chen XINNING LI JIALI KANG 《BIOCELL》 SCIE 2024年第8期1265-1273,共9页
Background:Despite improvements in objective response rates to cisplatin-based combination chemotherapy,the majority of advanced ovarian cancer remains suboptimal,resulting in poor survival.it has been found that non-... Background:Despite improvements in objective response rates to cisplatin-based combination chemotherapy,the majority of advanced ovarian cancer remains suboptimal,resulting in poor survival.it has been found that non-coding RNAs(ncRNAs)not only participate in the transmission of signals between various cells but also participate in tumor immunity and anti-tumor immune responses,thereby regulating tumor occurrence and development.However,the function and detailed mechanism of ultraconserved RNA(ucRNA)in ovarian cancer chemoresistance is still unclear.Methods:Western blotting assay,Quantitative real-time PCR analysis(qPCR),and Kaplan-Meier Plotter analysis were performed to analyze the expression and prognosis of uc.243 in ovarian carcinoma.Cytotoxicity assay and Annexin V assay were performed to analyze the function of uc.243 in cisplatin resistance in ovarian cancer cells.RNA pull-down and qPCR experiments were performed to explore the molecular mechanism of uc.243 enhancing cisplatin resistance in ovarian cancer cells.Results:Herein,we found that uc.243 was remarkably upregulated and correlated with patient survival in chemoresistance ovarian cancer patients compared with chemo-sensitive ovarian cancer.Functional experiment displayed that uc.243 induced cisplatin resistance on ovarian cancer cells by facilitating the efflux of cisplatin(CDDP);but inhibiting the expression of uc.243 significantly reverses this function.Mechanistically,uc.243 can inhibit the binding of RNA binding protein DGCR8 microprocessor complex subunit to pri-miR-155,thereby inhibiting the cleavage of pri-miR-155 and decrease in mature miR-155,subsequently upregulates the expression of ATP binding cassette subfamily B member(ABCB1,ABCC2).Conclusion:Our research findings indicate that uc.243 can induce chemotherapy resistance in ovarian cancer,suggesting that it may become a new prognostic biomarker for malignant ovarian cancer. 展开更多
关键词 Ultra-conserved non-coding RNA uc.243 Drug efflux Drug transporters Chemoresistance Ovarian cancer
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Temperature dependence of pattern transitions on water surface in contact with DC microplasmas
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作者 yanfei chen Bowen FENG +3 位作者 Qing ZHANG Ruoyu WANG Kostya(Ken)OSTRIKOV Xiaoxia ZHONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第5期63-69,共7页
The DC-driven atmospheric-pressure microplasma is generated in a helium gas flowing through the metal tube cathode and is brought into contact with the surface of the water with the immersed Pt anode.By adjusting the ... The DC-driven atmospheric-pressure microplasma is generated in a helium gas flowing through the metal tube cathode and is brought into contact with the surface of the water with the immersed Pt anode.By adjusting the gas flow,discharge current and gap distance,self-organized patterns are observed and varied sequentially from the homogeneous spot to the ring-like shape,distinct spot shape and the gearwheel shape on the water surface.The electrode temperature is measured and the gas temperature of the plasma discharge is calculated through the numericalfitting of the second positive system of the spectrum of N2 molecules.It is shown that the pattern transition is related to the electrode and gas temperatures of the plasma.Moreover,specific discretization features of the patterns are shown to appear at certain gas temperatures. 展开更多
关键词 MICROPLASMA self-organized pattern optical emission spectroscopy
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Features of Otolithic Dysfunction in Patients with Sudden Sensorineural Hearing Loss at Different Ages
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作者 Xiaorong Niu Qing Zhang +9 位作者 Xinda Xu Peng Han Ying cheng Ying Gao Rui Zhang Yintong Yang Zichen chen Juan Hu yanfei chen Min Xu 《Journal of Biosciences and Medicines》 2015年第10期1-8,共8页
Objective: To observe the otolithic function in sudden sensorineural hearing loss (SSHL) patients in different age groups by using vestibular evoked myogenic potentials (VEMPs). Methods: One hundred and seventy unilat... Objective: To observe the otolithic function in sudden sensorineural hearing loss (SSHL) patients in different age groups by using vestibular evoked myogenic potentials (VEMPs). Methods: One hundred and seventy unilateral SSHL patients were divided into 5 age groups. The 170 affected ears belonged to study group. The opposite healthy ears of 170 patients and 138 normal ears of 69 age and sex-matched normal people at different ages were set as control groups. Ocular VEMP (oVEMP) and cervical VEMP (cVEMP) both evoked by air-conducted sound (ACS) were employed for vestibular otolithic function assessment. Results: The response rates of cVEMP and oVEMP were lower and abnormal rates were higher in affected ears of SSHL patients compared to the opposite healthy ears and normal control ears in all age groups, except patients over 60 years. The response rates of VEMPs significantly declined with increasing age, not only in normal control ears, but also in affected and healthy ears of SSHL patients. But, the abnormal rates of VEMPs showed no significant difference in affected ears at different ages. Conclusions: Dysfunction of vestibular otolithic organs in SSHL patients presented respective features at different ages. It is necessary to consider the age when the clinicians determine the otolithic condition of patients based on the VEMPs. 展开更多
关键词 OCULAR VESTIBULAR EVOKED MYOGENIC POTENTIAL (oVEMP) Cervical VESTIBULAR EVOKED MYOGENIC POTENTIAL (cVEMP) SSHL Age Otolithic Function
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Characteristics of Diesel/N-Butanol Blend on a Common Rail Diesel Engine with Exhaust Gas Recirculation
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作者 yanfei chen Jingjing He +2 位作者 Hao chen Xin Su Bin Xie 《Energy Engineering》 EI 2022年第3期1239-1259,共21页
20%n-butanol is blended in diesel by volume(noted as D80B20)and experiment has been carried out to study the effect on the combustion and emission characteristics based on a common rail diesel engine with exhaust gas ... 20%n-butanol is blended in diesel by volume(noted as D80B20)and experiment has been carried out to study the effect on the combustion and emission characteristics based on a common rail diesel engine with exhaust gas recirculation(EGR)system.The results reveal thatD80B20 has longer ignition delay,shorter combustion duration and higher maximumin-cylinder temperature than pure diesel(noted as D100).Further,the number concentration and volume concentration of ultrafine particles decrease significantly while NO_(X) emissions increase a little with the addition of n-butanol.When the exhaust gas is induced into cylinder,NO_(X) emissions significantly decrease and ultrafine particles emissions increase.The number geometric mean diameters and volume geometricmean diameters of ultrafine particles increase withEGR ratio.Compared toD100 without EGR,D80B20 with 20%EGR ratio can reduce both NO_(X) and ultrafine particles emissions at 0.14MPa BMEP and 0.56MPa BMEP. 展开更多
关键词 N-BUTANOL ultrafine particles COMBUSTION EMISSION common rail diesel engine
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Large Storage Tank Structure Design Cases-Based Teaching in Teaching Reform for Major of Oil&Gas Storage and Transportation Engineering
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作者 yanfei chen Heng Ni +1 位作者 Hong Zhang Fuheng Hou 《Journal of Educational Theory and Management》 2021年第1期5-9,共5页
As one of the compulsory courses of oil and gas storage and transportation engineering,“Strength Design and Safety Management of Storage and Transportation Facilities”is a comprehensive course of both practicality a... As one of the compulsory courses of oil and gas storage and transportation engineering,“Strength Design and Safety Management of Storage and Transportation Facilities”is a comprehensive course of both practicality and theory.In order to solve the unbalanced distribution of theoretical and applied content in the teaching process,the teaching team reformed the teaching mode of the structure design of large storage tanks in the course of“Strength Design and Safety Management of Storage and Transportation Facilities”and introduced case-based teaching.On the basis of the original course,practical engineering case analysis such as wind-induced buckling of large storage tank and uneven settlement of tank foundation was added,which increased the proportion of application content.It is a new type of discussion teaching integrating case collection,group discussion and afterclass experience exchange.According to the recent three years of teaching practice,students’interest in this course has increased greatly and teaching quality has improved significantly,which fully verified the feasibility of engineering case-based teaching in teaching reform.The teaching team has gradually improved the teaching process according to the relevant experience and lessons in classroom practice and made a successful attempt in the teaching reform of storage and transportation structure safety courses,which is of positive significance for training application-oriented composite talents with the ability to solve practical problems in the new era. 展开更多
关键词 Large storage tank Teaching reform Project case Case-based teaching
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