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Topology transition description of horseshoe vortex system in junctureflows with velocity characteristic lines
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作者 Bo Hu Hua Zhang +1 位作者 ran li Qingkuan liu 《Theoretical & Applied Mechanics Letters》 CSCD 2024年第6期540-547,共8页
Particle image velocimetry and numerical simulation results of juncture flows were analyzed to parametrically investigate topology transition. The vortex system evolutions from non-vortex to multi-vortex with variatio... Particle image velocimetry and numerical simulation results of juncture flows were analyzed to parametrically investigate topology transition. The vortex system evolutions from non-vortex to multi-vortex with variations in obstacle bluntness, obstacle width, flow velocity, and boundary layer thickness are discussed from the perspective of velocity characteristic lines. The velocity characteristic lines of u = 0, υ = 0, and ∇^(2) υ = 0 are adopted to describe the vortex system evolution. The motions of the characteristic lines with juncture flow parameters are described in detail, and the corresponding reflections of the vortex system patterns are illustrated. A panoramic picture of the development of velocity characteristic lines corresponding to the HSV topology transition from a non-vortex to a multi-vortex system with variations in the juncture flow parameter is established. Two methods for determining the attachment/separation pattern of the most upstream singularity are proposed. One method is based on the number of intersections of the u = 0 and υ = 0 velocity characteristic curve lines, and the other is based on the relative positions of the most upstream feet of the u = 0 and υ = 0 loop curves with both feet attached to the wall. 展开更多
关键词 Juncture flow Topology transition Velocity characteristic lines
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Uncovering Small RNAs in Penicillium digitatum by Transcriptome Sequencing 被引量:1
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作者 Pengcheng Zhang Qinru Yu +2 位作者 ran li Yaoyao liu Tongfei Lai 《American Journal of Plant Sciences》 CAS 2022年第7期1006-1022,共17页
Small RNAs in Penicillium digitatum were identified and analyzed via transcriptome sequencing on the BGISEQ-500 platform. A total of 15 predicted miRNAs and 10718 novel siRNAs were found. Their length distribution, se... Small RNAs in Penicillium digitatum were identified and analyzed via transcriptome sequencing on the BGISEQ-500 platform. A total of 15 predicted miRNAs and 10718 novel siRNAs were found. Their length distribution, sequence, predicted construction, base bias, expression levels and potential targets were determined as well. Through pathway and KEGG enrichment analysis, the miRNA target genes were mostly involved in carbohydrate metabolism, transport and catabolism, translation and amino acid metabolism. The target genes involved in aflatoxin biosynthesis and proteasome had a higher rich factor value. The results will provide a theoretical foundation for understanding the developmental and pathogenic mechanisms of P. digitatum at the transcriptional level. 展开更多
关键词 Penicillium digitatum Transcriptome Sequencing MICRORNA Small Interfering RNA
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Rolling velocity and relative motion of particle detector in local granular flow
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作者 ran li Bao-lin liu +1 位作者 Gang Zheng Hui Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期388-394,共7页
The velocity of a particle detector in granular flow can be regarded as the combination of rolling and sliding velocities.The study of the contribution of rolling velocity and sliding velocity provides a new explanati... The velocity of a particle detector in granular flow can be regarded as the combination of rolling and sliding velocities.The study of the contribution of rolling velocity and sliding velocity provides a new explanation to the relative motion between the detector and the local granular flow.In this study,a spherical detector using embedded inertial navigation technology is placed in the chute granular flow to study the movement of the detector relative to the granular flow.It is shown by particle image velocimetry(PIV)that the velocity of chute granular flow conforms to Silbert’s formula.And the velocity of the detector is greater than that of the granular flow around it.By decomposing the velocity into sliding and rolling velocity,it is indicated that the movement of the detector relative to the granular flow is mainly caused by rolling.The rolling detail shown by DEM simulation leads to two potential mechanisms based on the position and drive of the detector. 展开更多
关键词 local velocity distribution rolling velocity inertial navigation technology relative velocity dependent(RVD)rolling friction
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Effect of granular shape on radial segregation in a two-dimensional drum
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作者 徐悦 李然 +3 位作者 迟志鹏 修文正 孙其诚 杨晖 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期509-514,共6页
Granular segregation is widely observed in nature and industry.Most research has focused on segregation caused by differences in the size and density of spherical grains.However,due to the fact that grains typically h... Granular segregation is widely observed in nature and industry.Most research has focused on segregation caused by differences in the size and density of spherical grains.However,due to the fact that grains typically have different shapes,the focus is shifting towards shape segregation.In this study,experiments are conducted by mixing cubic and spherical grains.The results indicate that spherical grains gather at the center and cubic grains are distributed around them,and the degree of segregation is low.Through experiments,a structured analysis of local regions is conducted to explain the inability to form stable segregation patterns with obviously different geometric shapes.Further,through simulations,the reasons for the central and peripheral distributions are explained by comparing velocities and the number of collisions of the grains in the flow layer. 展开更多
关键词 granular materials cubic grains shape segregation segregation mechanism
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Probiotic Lactobacillus rhamnosus GG improves insulin sensitivity and offspring survival via modulation of gut microbiota and serum metabolite in a sow model
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作者 Tianle Gao ran li +13 位作者 liang Hu Quanfang Hu Hongmei Wen Rui Zhou Peiqiang Yuan Xiaoling Zhang lingjie Huang Yong Zhuo Shengyu Xu Yan lin Bin Feng lianqiang Che De Wu Zhengfeng Fang 《Journal of Animal Science and Biotechnology》 CSCD 2024年第6期2506-2523,共18页
Background Sows commonly experience insulin resistance in late gestation and lactation,causing lower feed intake and milk production,which can lead to higher mortality rates in newborn piglets.The probiotic Lactobacif... Background Sows commonly experience insulin resistance in late gestation and lactation,causing lower feed intake and milk production,which can lead to higher mortality rates in newborn piglets.The probiotic Lactobaciflus rhamnosus GG(LGG)is known to improve insulin resistance.However,whether supplementing LGG can improve insulin sensitivity in sows and enhance lactation performance,particularly the early survival of offspring remains unclea r.Hence,we explored the effects and mechanisms of supplementing LGG during late gestation and lactation on sow insulin sensitivity,lactation performance,and offspring survival.In total,20 sows were randomly allocated to an LGG(n=10)and control group(n=10).Results In sows,LGG supplementation significantly improved insulin sensitivity during late gestation and lactation,increased feed intake,milk production and colostrum lactose levels in early lactation,and enhanced newborn piglet survival.Moreover,LGG treatment significantly reshaped the gut microbiota in sows,notably increasing microbiota diversity and enriching the relative abundance of insulin sensitivity-associated probiotics such as Lactobacillus,Bifidobacterium,and Bacteroides.Serum metabolite and amino acid profiling in late-gestation sows also revealed decreased branched-chain amino acid and kynurenine serum levels following LGG supplementation.Further analyses highlighted a correlation between mitigated insulin resistance in late pregnancy and lactation by LGG and gut microbiota reshaping and changes in serum amino acid metabolism.Furthermore,maternal LGG enhanced immunity in newborn piglets,reduced inflammation,and fa cilitated the establishment of a gut microbiota.Conclusions We provide the first evidence that LGG mitigates insulin resistance in sows and enhances offspring survival by modulating the gut microbiota and amino acid metabolism. 展开更多
关键词 Gut microbiota Insulin resistance Lactobacillus rhamnosus GG Lactation performance PIGLET SOW
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First Report of a Postharvest Fruit Rot on Apple Caused by <i>Diaporthe phaseolorum</i>var. <i>caulivora</i>in China: A Note
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作者 Yuanzhi Chen Quan Zhou +3 位作者 Yangying Sun ran li Yaoyao liu Ting Zhou 《American Journal of Plant Sciences》 2020年第10期1612-1617,共6页
Brown rots of Red Fuji apples were observed in Hangzhou city (Zhengjiang Province, China). The causal agent was isolated and identified in both morphological and molecular genetic levels. The phenotype and phylogeneti... Brown rots of Red Fuji apples were observed in Hangzhou city (Zhengjiang Province, China). The causal agent was isolated and identified in both morphological and molecular genetic levels. The phenotype and phylogenetic analysis revealed that the isolate was </span><i><span style="font-family:Verdana;">Diaporthe phaseolorum</span></i><span style="font-family:Verdana;"> var. </span><i><span style="font-family:Verdana;">caulivora</span></i><span style="font-family:Verdana;">, and its pathogenicity on apple fruit was confirmed by re-inoculation experiment. To our knowledge, this is the first report of </span><i><span style="font-family:Verdana;">D. phaseolorum</span></i><span style="font-family:Verdana;"> var. </span><i><span style="font-family:Verdana;">caulivora</span></i><span style="font-family:Verdana;"> causing postharvest fruit rot on apple in China. 展开更多
关键词 APPLE Postharvest Pathogen ITS-rDNA Diaporthe phaseolorum var. caulivora
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刺血醒脑法对大鼠脑缺血再灌注损伤的脑保护作用实验研究
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作者 曾子修 刘晓君 +3 位作者 官玥玥 冉丽 罗晓琼 唐军 《中国中医急症》 2025年第3期409-415,共7页
目的利用转录组测序(RNA-seq)技术探究刺血醒脑法对大鼠脑缺血再灌注损伤的脑保护作用及其潜在机制。方法将75只SD大鼠随机分为假手术组、模型组和刺血醒脑组。采用改良线栓法建立脑缺血再灌注(MCAO/R)模型,并对模型组大鼠实施刺血醒脑... 目的利用转录组测序(RNA-seq)技术探究刺血醒脑法对大鼠脑缺血再灌注损伤的脑保护作用及其潜在机制。方法将75只SD大鼠随机分为假手术组、模型组和刺血醒脑组。采用改良线栓法建立脑缺血再灌注(MCAO/R)模型,并对模型组大鼠实施刺血醒脑法干预。在缺血再灌注后0、24、48、72 h关键时间点,记录大鼠存活率和体重变化,采用Garcia评分评估神经功能,旷场试验评价行为学表现,TTC染色法观察和定量分析脑梗死体积,HE染色检测脑组织病理形态学,TUNEL染色检测细胞凋亡;利用RNA-seq技术筛选刺血醒脑法治疗后的关键靶点及调控途径,并通过Western blotting验证相关通路。结果在脑缺血再灌注后72 h,刺血醒脑法显著改善了MCAO/R模型大鼠的神经功能缺损及行为学测试结果,缩小了脑梗死体积,保护了脑组织细胞结构的完整性,并减少了神经细胞凋亡(P<0.05);转录组学研究显示,刺血醒脑法干预后,差异基因富集通路与NOD样受体信号通路显著相关,其中Nlrp3、Casp1、IL-18等基因表达显著下调。Western blotting结果表明,与模型组相比,刺血醒脑组中NLRP3、ASC、Caspase-1、IL-1β、IL-18等蛋白表达水平明显下降(P<0.05)。结论刺血醒脑法对脑缺血再灌注损伤的大鼠具有显著的脑保护作用,其作用机制可能涉及抑制NLRP3/Caspase-1/IL-1β信号通路,进而发挥抗炎效应。 展开更多
关键词 脑缺血再灌注 针刺 刺血醒脑法 转录组学 NLRP3/Caspase-1/IL-1β 大鼠
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续命通脉汤联合替罗非班治疗静脉溶栓后早期神经功能恶化的急性缺血性卒中患者的临床疗效
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作者 冉丽 曾子修 +1 位作者 官玥玥 唐军 《现代医药卫生》 2025年第1期57-61,共5页
目的探讨续命通脉汤联合替罗非班治疗静脉溶栓后早期神经功能恶化的急性缺血性卒中(AIS)患者的临床疗效及安全性。方法纳入2020年1月至2023年12月该院卒中单元收治的接受静脉溶栓治疗,并在治疗24 h内出现神经功能恶化的AIS患者,共52例,... 目的探讨续命通脉汤联合替罗非班治疗静脉溶栓后早期神经功能恶化的急性缺血性卒中(AIS)患者的临床疗效及安全性。方法纳入2020年1月至2023年12月该院卒中单元收治的接受静脉溶栓治疗,并在治疗24 h内出现神经功能恶化的AIS患者,共52例,采用随机数字表法将其分为联合治疗组和常规治疗组。常规治疗组为静脉予以替罗非班治疗24 h,联合治疗组在替罗非班治疗基础上予以续命通脉汤联合治疗。分别于治疗前及治疗14 d后,对2组患者的美国国立卫生研究院卒中量表(NIHSS)评分、改良运动功能(mRS)评分、Barthel指数(BI)评分、血清神经元特异性烯醇化酶(NSE)、S100B蛋白浓度等多个维度进行评估,并以90 d mRS评分判定患者远期预后。结果与治疗前相比,2组患者治疗14 d后NIHSS评分、mRS评分、BI评分均明显改善,NSE及S100B水平均显著降低,且联合治疗组患者上述指标改善情况优于常规治疗组,差异均有统计学意义(P<0.05)。随访90 d,联合治疗组患者远期神经功能预后良好(mRS≤2分)比例高于常规治疗组[88.5%(23/26)vs.65.4%(17/26)],差异有统计学意义(P<0.05)。结论续命通脉汤与替罗非班联合治疗可显著改善静脉溶栓后早期神经功能恶化的AIS患者神经功能缺损症状,具有临床应用价值。 展开更多
关键词 续命通脉汤 替罗非班 急性缺血性卒中 早期神经功能恶化 静脉溶栓
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双层电介质界面极化电流测量装置的设计与实现 被引量:1
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作者 曹晓燕 周凯 +2 位作者 冉立 杨帆 王吉祥 《实验室研究与探索》 CAS 北大核心 2024年第3期36-40,共5页
界面夹层极化现象是高电压技术中的重要知识点。为了使学生更好地掌握双层电介质界面极化电流的测量,研制了一套界面极化电流测量装置——极化-去极化电流测量装置。基于极化-去极化电流测量原理,设计了无线传输数据的皮安表、可输出0~5... 界面夹层极化现象是高电压技术中的重要知识点。为了使学生更好地掌握双层电介质界面极化电流的测量,研制了一套界面极化电流测量装置——极化-去极化电流测量装置。基于极化-去极化电流测量原理,设计了无线传输数据的皮安表、可输出0~5 kV电压的程控直流高压电源以及分析显示数据的上位机控制程序,然后基于该测量装置设计了双层电介质界面极化电流测量实验。结果表明,该测量装置解决了双层电介质界面极化电流不易测量、学生理解难的问题。将实验教学与实际工程问题紧密连接,把微观的工程技术问题转变为宏观的实验现象,对于培养学生的科研思维及分析问题、解决问题能力有重要意义。 展开更多
关键词 双层电介质 界面极化电流 皮安表 测量实验 工程问题
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The IES dynamic time-scale scheduling strategy based on multiple load forecasting errors 被引量:5
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作者 Fan Sun ran li +3 位作者 Yi Han Shouang liu Fanrui liu Huilan liu 《Global Energy Interconnection》 CAS CSCD 2021年第1期58-68,共11页
Considering the complex coupling of multiple energies and the varying load forecasting errors for an integrated energy system(IES),this study proposes a dynamic time-scale scheduling strategy based on long short-term ... Considering the complex coupling of multiple energies and the varying load forecasting errors for an integrated energy system(IES),this study proposes a dynamic time-scale scheduling strategy based on long short-term memory(LSTM)and multiple load forecasting errors.This strategy dynamically selects a hybrid timescale which is suitable for a variety of energies for each month.This is obtained by combining the mean absolute percentage error(MAPE)curve of the load forecasting with the error restriction requirements of the dispatcher.Based on the day-ahead scheduling plan,the output of the partial equipment is selectively adjusted at each time-scale to realize multi-energy collaborative optimization and gives full play to the comprehensive advantages of the IES.This is achieved by considering the differences in the response speed for each piece of equipment within the intra-day scheduling.This study uses the IES as an example,and it dynamically determines the time scale of the energy monthly.In addition,this investigation presents a detailed analysis of the output plan of the key equipment to demonstrate the necessity and the advantages of the strategy. 展开更多
关键词 integrated energy system long short-term memory dynamic time-scale multi-layer optimization
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Analysis of the wide area differential correction for BeiDou global satellite navigation system 被引量:4
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作者 ran li Yue-ling Cao +6 位作者 Xiao-Gong Hu Cheng-Pan Tang Shan-Shi Zhou Xin Meng li liu ran-ran Su Zhi-Qiao Chang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第11期17-28,共12页
The regional BeiDou Satellite System, or BDS2, broadcasts a differential correction as Equivalent Satellite Clock Correction to correct both orbit and satellite clock errors. For the global BDS, or BDS3, satellite orb... The regional BeiDou Satellite System, or BDS2, broadcasts a differential correction as Equivalent Satellite Clock Correction to correct both orbit and satellite clock errors. For the global BDS, or BDS3, satellite orbit and clock corrections conforming with RTCA standards will be broadcast to authorized users. The hybrid constellation and regional monitoring network pose challenges for the high precision separation of orbit and satellite clock corrections. Three correction models of kinematic,dynamic and Two-way Satellite Time Frequency Transfer(TWSTFT)-based dynamic were studied to estimate the satellite orbit and clock corrections. The correction accuracy of the three models is compared and analyzed based on the BDS observation data. Results show that the accuracies(root mean square, RMS) of dual-frequency real-time positioning for the three models are about 1.76 m, 1.78 m and 2.08 m respectively, which are comparable with the performance of WAAS and EGNOS. With dynamic corrections, the precision of Precise Point Positioning(PPP) experiments may reach about 23 cm after convergence. 展开更多
关键词 celestial mechanics methods: data analysis space vehicles
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Protection effect of trigonelline on liver of rats with non-alcoholic fatty liver diseases 被引量:2
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作者 Dong-Fang Zhang Fan Zhang +2 位作者 Jin Zhang Rui-Ming Zhang ran li 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第8期639-642,共4页
Objective: To study the effect of trigonelline on the change of indicators of serum transaminase, lipoprotein and liver lipid of model rats with non-alcoholic fatty liver diseases and on the expression level of Bcl-2 ... Objective: To study the effect of trigonelline on the change of indicators of serum transaminase, lipoprotein and liver lipid of model rats with non-alcoholic fatty liver diseases and on the expression level of Bcl-2 and Bax proteins. Methods: A total of 45 SD rats were randomly divided into Fthe control group, model group and trigonelline intervention group. Rats in the control group were fed with the common diet, while rats in the model group and intervention group were fed with the high fat diet. 8 weeks later, the intervention group received the intragastric administration of trigonellin e(with the dosage of 40 mg/kg/d) for 8 weeks; while control group and model group received the intragastric administration of saline with the equal dosage. Blood was taken from the abdominal aorta of rats 8 weeks later, detecting the level of a series of indicators of ALT, AST, TG, TC, HDL-C and LDL-C in the serum. After the rats were sacrificed, detect the indicators of TG, TC, SOD and MDA in the liver tissue of rats, as well as the expression of Bcl-2 and Bax in the liver tissue. Results: Results of histopathologic examination showed that the damage degree of liver for rats in the trigonellineintervention group was smaller than the one in the model group, with significantly reduced hepatic steatosis and the partially visible hepatic lobule. The levels of ALT, AST, TC and LDL-C in the serum of rats in the trigonelline group were significantly reduced, while the change in the levels of TG and HDL-C was not significantly different. The levels of TG, TC and MDA in the liver tissues were significantly decreased, while the level of SOD significantly increased; the expression of Bcl-2 protein in the liver tissues of rats in the trigonelline intervention group was significantly increased, while the expression of Bax protein significantly decreased. Conclusions: The trigonelline contributes to the therapeutic effect of non-alcoholic fatty liver diseases. It can also increase the expression of Bcl-2 protein and decrease the expression of Bax protein in the liver tissues, which can protect the liver. 展开更多
关键词 TRIGONELLINE Non-alcoholic FATTY LIVER DISEASES Bcl-2 BAX
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Natriuretic peptide family as diagnostic/prognostic biomarker and treatment modality in management of adult and geriatric patients with heart failure: remaining issues and challenges 被引量:2
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作者 Zhen-Lu ZHANG ran li +1 位作者 Fei-Yan YANG Lei XI 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第8期540-546,共7页
B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP), the key members of natriuretic peptide family have been rec- ommended as the gold standard biomarkers for the diagnosis and prognosis of heart fa... B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP), the key members of natriuretic peptide family have been rec- ommended as the gold standard biomarkers for the diagnosis and prognosis of heart failure (HF) according to the current clinical guidelines. However, recent studies have revealed many previously unrecognized features about the natriuretic peptide family, including more accurate utilization of BNP and NT-proBNP in diagnosing HF. The pathophysiological mechanisms behind natriuretic peptide release, breakdown, and clearance are very complex and the diverse nature of circulating natriuretic peptides and fragments makes analytical detection particu- larly challenging. In addition, a new class of drug therapy, which works via natriuretic peptide family, has also been considered promising for cardiology application. Under this context, our present mini-review aims at providing a critical analysis on these new progresses on BNP and NT-proBNP with a special emphasis on their use in geriatric cardiology settings. We have focused on several remaining issues and chal- lenges regarding the clinical utilization of BNP and NT-proBNP, which include: (1) Different prevalence and diagnostic/prognostic values of BNP isoforms; (2) methodological issues on detection of BNP; (3) glycosylation of proBNP and its effect on biomarker testing; (4) specificity and comparability of BNP/NT-proBNP resulted from different testing platforms; (5) new development of natriuretic peptides as HF treatment modality; (6) BNP paradox in HF; and (7) special considerations of using BNP/NT-proBNP in elderly HF patients. These practical discussions on BNP/NT-proBNP may be instrumental for the healthcare providers in critically interpreting laboratory results and effective management of the HF patients. 展开更多
关键词 Angiotensin-renin-neprilysin-inhibitors Biomarker BNP Heart failure NT-proBNP
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Shale gas transport in nanopores with mobile water films and water bridge 被引量:1
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作者 ran li Zhangxin Chen +1 位作者 Keliu Wu Jinze Xu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1068-1076,共9页
Gas flow properties in nanopores are significantly determined by the flow patterns. Slug flow pattern is a potential water–gas two phase flow pattern, in which gas molecules flow in form of gas slugs and water molecu... Gas flow properties in nanopores are significantly determined by the flow patterns. Slug flow pattern is a potential water–gas two phase flow pattern, in which gas molecules flow in form of gas slugs and water molecules separate gas slugs. Considering water slippage, a portion of water molecules accumulates at the wall with lower mobility, while the remaining water molecules take the shape of a water bridge. Adopting foam apparent viscosity model to represent slug rheological behavior, how water bridge disturbs on gas flow capacity is estimated. The results are compared with the water–gas two phase flow model that assumes annular flow pattern as well as the single gas flow model without the consideration of water. The comparison illustrates that gas molecular movement is significantly hindered by flow space reduction and loss of gas slippage. The impact from water phase of slug flow pattern is more significant than that of annular flow pattern on gas flow capacity. It is discovered that larger nanopores improve gas flow capacity while maintaining bulk water layer thickness and increasing water bridge thickness tend to reduce gas transport ability. A better understanding of the structure and transport of water and gas molecules is conducive to figure out the specific gas–water flow behavior and predict shale gas production. 展开更多
关键词 Shale gas Water bridge Water film NANOPORE
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A novel particle tracking velocimetry method for complex granular flow field 被引量:1
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作者 Bi-De Wang Jian Song +3 位作者 ran li Ren Han Gang Zheng Hui Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期293-299,共7页
Particle tracking velocimetry(PTV)is one of the most commonly applied granular flow velocity measurement methods.However,traditional PTV methods may have issues such as high mismatching rates and a narrow measurement ... Particle tracking velocimetry(PTV)is one of the most commonly applied granular flow velocity measurement methods.However,traditional PTV methods may have issues such as high mismatching rates and a narrow measurement range when measuring granular flows with large bulk density and high-speed contrast.In this study,a novel PTV method is introduced to solve these problems using an optical flow matching algorithm with two further processing steps.The first step involves displacement correction,which is used to solve the mismatching problem in the case of high stacking density.The other step is trajectory splicing,which is used to solve the problem of a measurement range reduction in the case of high-speed contrast The hopper flow experimental results demonstrate superior performance of this proposed method in controlling the number of mismatched particles and better measuring efficiency in comparison with the traditional PTV method. 展开更多
关键词 particle tracking velocimetry optical flow displacement correction trajectory splicing
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Hypothyroidism with elevated pancreatic amylase and lipase without clinical symptoms: A case report 被引量:1
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作者 Yong-Wei Xu ran li Shu-Chang Xu 《World Journal of Clinical Cases》 SCIE 2020年第15期3299-3304,共6页
BACKGROUND Hypothyroidism is an endocrine disorder that has worldwide prevalence and can affect multiple organ systems.We report a case of hypothyroidism with elevated pancreatic amylase and trypsin without acute panc... BACKGROUND Hypothyroidism is an endocrine disorder that has worldwide prevalence and can affect multiple organ systems.We report a case of hypothyroidism with elevated pancreatic amylase and trypsin without acute pancreatitis.No such case has been previously reported.CASE SUMMARY A 29-year-old woman did not pay much attention to a fever 4 d prior.During this time,she experienced anorexia and only drank a small amount of water every day.She did not present with abdominal distension,postprandial nausea,vomiting,cough or expectoration.After physical and laboratory examinations,the patient was diagnosed with hypothyroidism.During the course of the disease,hypothyroidism was generally accompanied by constantly increased pancreatic amylase and trypsin.After admission,the possible etiology of the patient was excluded and the concentrations of pancreatic lipase and amylase in serum were>2000U/L(reference range 23-300 U/L)and 410 U/L(reference range 30-110 U/L),respectively.So we highly suspected that it may be acute pancreatitis.Interestingly,she never developed any complications associated with acute pancreatitis despite high levels of serum pancreatic amylase and trypsin,and she reported no symptoms of abdominal pain.Serum amylase and lipase decreased gradually after active thyroxine supplementation,and the patient was discharged from the hospital after active treatment.CONCLUSION This case suggests that clinicians should pay attention to hypothyroidism with elevated pancreatic amylase and trypsin,even if no complications of acute pancreatitis are reported. 展开更多
关键词 HYPOTHYROIDISM AMYLASE TRYPSIN Acute pancreatitis Clinical symptoms Case report
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Systematic Errors Induced by the Elliptical Power-law model in Galaxy–Galaxy Strong Lens Modeling 被引量:1
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作者 Xiaoyue Cao ran li +9 位作者 J.W.Nightingale Richard Massey Andrew Robertson Carlos SFrenk Aristeidis Amvrosiadis Nicola CAmorisco Qiuhan He Amy Etherington Shaun Cole Kai Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第2期143-172,共30页
The elliptical power-law model of the mass in a galaxy is widely used in strong gravitational lensing analyses.However,the distribution of mass in real galaxies is more complex.We quantify the biases due to this model... The elliptical power-law model of the mass in a galaxy is widely used in strong gravitational lensing analyses.However,the distribution of mass in real galaxies is more complex.We quantify the biases due to this model mismatch by simulating and then analyzing mock Hubble Space Telescope imaging of lenses with mass distributions inferred from SDSS-Ma NGA stellar dynamics data.We find accurate recovery of source galaxy morphology,except for a slight tendency to infer sources to be more compact than their true size.The Einstein radius of the lens is also robustly recovered with 0.1%accuracy,as is the global density slope,with 2.5%relative systematic error,compared to the 3.4%intrinsic dispersion.However,asymmetry in real lenses also leads to a spurious fitted"external shear"with typical strengthγext=0.015.Furthermore,time delays inferred from lens modeling without measurements of stellar dynamics are typically underestimated by~5%.Using such measurements from a sub-sample of 37 lenses would bias measurements of the Hubble constant H0 by~9%.Although this work is based on a particular set of Ma NGA galaxies,and the specific value of the detected biases may change for another set of strong lenses,our results strongly suggest the next generation cosmography needs to use more complex lens mass models. 展开更多
关键词 galaxies:structure galaxies:halos gravitational lensing:strong
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玻璃纤维增强聚合物筋增强混凝土柱的轴压承载力评估 被引量:1
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作者 冉黎 吴文 周磊 《复合材料科学与工程》 CAS 北大核心 2024年第10期72-78,共7页
玻璃纤维增强聚合物(GFRP)筋对混凝土柱承载力的影响十分关键,为深入评估GFRP筋设计应用于增强混凝土柱的承载力性能,利用随机森林(RF)、人工神经网络(ANN)、AdaBoost和XGBoost算法,分别建立了各自的GFRP筋增强混凝土柱承载力模型。建立... 玻璃纤维增强聚合物(GFRP)筋对混凝土柱承载力的影响十分关键,为深入评估GFRP筋设计应用于增强混凝土柱的承载力性能,利用随机森林(RF)、人工神经网络(ANN)、AdaBoost和XGBoost算法,分别建立了各自的GFRP筋增强混凝土柱承载力模型。建立了GFRP筋增强混凝土柱的试验数据库,对已有的GFRP筋增强混凝土柱承载力理论公式进行了初步评估,并进一步对比分析GFRP筋增强混凝土柱承载力的RF模型、ANN模型、AdaBoost模型和XGBoost模型的预测精度。结果表明:已有的GFRP筋增强混凝土柱承载力理论公式的判定系数(0.70左右)均小于RF模型(0.82)、AdaBoost模型(0.80)和XGBoost模型(0.80)的制定系数,且平均绝对误差和均方根误差基本都大于RF模型、ANN模型、AdaBoost模型和XGBoost模型的相应值,表明现有理论公式的准确性低于RF模型、ANN模型、AdaBoost模型和XGBoost模型准确性。与ANN模型相比,RF模型、AdaBoost模型和XGBoost模型均可较为准确地评估GFRP筋增强混凝土柱的实际承载力性能(尤其是RF模型)。研究可为GFRP筋设计应用于增强混凝土结构时的承载力设计和分析提供参考。 展开更多
关键词 玻璃纤维增强聚合物筋 混凝土柱 轴压承载力 复合材料 随机森林
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Simultaneous determination of clopidogrel,2-oxo-clopidogrel,and the thiol metabolite of clopidogrel in human plasma by LC-MS/MS
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作者 Lei Xu ran li +7 位作者 Juan li Zhou Dong Jiaxin Zong Chuchu Tan Zekang Ye Lu Shi Xiaoxuan Gong Chunjian li 《The Journal of Biomedical Research》 CAS CSCD 2022年第2期109-119,共11页
Clopidogrel is a pro-drug which needs two-step metabolism to produce the active thiol metabolite.This study aimed to explore an efficient method to simultaneously determine the plasma clopidogrel,2-oxo-clopidogrel(2-O... Clopidogrel is a pro-drug which needs two-step metabolism to produce the active thiol metabolite.This study aimed to explore an efficient method to simultaneously determine the plasma clopidogrel,2-oxo-clopidogrel(2-Oxo-CLP),and the clopidogrel active metabolite(CAM).A high-throughput liquid chromatography tandem mass spectrometry(LC-MS/MS)was therefore developed.The analytes were extracted from plasma by using methyl tert-butyl ether(MTBE).Chromatographic separation was performed on a C18 column under an isocratic elution,accompanied with acetonitrile and deionized water containing 0.1%formic acid.After optimizing the condition of LC-MS/MS,a stable linearity was observed in the standard curves over the concentration ranges of 0.05 to 50.0 ng/mL for clopidogrel,0.5 to 50.0 ng/mL for 2-Oxo-CLP,and 0.5 to 100 ng/mL for clopidogrel active metabolite derivative(CAMD).The retention time was 4.78 minutes,3.79 minutes,3.59 minutes,and 4.82 minutes for clopidogrel,2-Oxo-CLP,CAMD,and internal standard,respectively.Both the relative standard deviation and the relative error were within the requirement of operating criteria.No significant degradation of clopidogrel,2-Oxo-CLP,and CAMD occurred under different storage conditions.This method was successfully validated in 3 patients with coronary artery disease.The results showed that the current LC-MS/MS method was efficient for simultaneously detecting clopidogrel,2-Oxo-CLP,and CAM with fine linearity,accuracy,precision,and stability. 展开更多
关键词 CLOPIDOGREL drug metabolites liquid chromatography tandem mass spectrometry coronary artery disease
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Novel glucose-lowering drugs for non-alcoholic fatty liver disease
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作者 Zuo-Di Fu Xiao-ling Cai +3 位作者 Wen-Jia Yang Ming-Ming Zhao ran li Yu-Feng li 《World Journal of Diabetes》 SCIE 2021年第1期84-97,共14页
BACKGROUND The efficacy of novel glucose-lowering drugs in treating non-alcoholic fatty liver disease(NAFLD)is unknown.AIM To evaluate the efficacy of glucose-lowering drugs dipeptidyl peptidase-4(DPP-4)inhibitors,glu... BACKGROUND The efficacy of novel glucose-lowering drugs in treating non-alcoholic fatty liver disease(NAFLD)is unknown.AIM To evaluate the efficacy of glucose-lowering drugs dipeptidyl peptidase-4(DPP-4)inhibitors,glucagon-like peptide-1 receptor agonists(GLP-1 RAs),and sodiumglucose cotransporter 2(SGLT2)inhibitors in treating NAFLD and to perform a comparison between these treatments.METHODS Electronic databases were systematically searched.The inclusion criteria were:Randomized controlled trials comparing DPP-4 inhibitors,GLP-1 RAs,or SGLT2 inhibitors against placebo or other active glucose-lowering drugs in NAFLD patients,with outcomes of changes in liver enzyme[alanine aminotransferase(ALT)and/or aspartate aminotransferase(AST)]from baseline.RESULTS Nineteen studies were finally included in this meta-analysis.Compared with placebo or other active glucose-lowering drug treatment,treatment with DPP-4 inhibitors,GLP-1 RAs,and SGLT2 inhibitors all led to a significant decrease in ALT change and AST change from baseline.The difference between the DPP-4 inhibitor and SGLT2 inhibitor groups in ALT change was significant in favor of DPP-4 inhibitor treatment(P<0.05).The trends of reduction in magnetic resonance imaging proton density fat fraction and visceral fat area changes were also observed in all the novel glucose-lowering agent treatment groups.CONCLUSION Treatment with DPP-4 inhibitors,GLP-1 RAs,and SGLT2 inhibitors resulted in improvements in serum ALT and AST levels and body fat composition,indicating a beneficial effect in improving liver injury and reducing liver fat in NAFLD patients. 展开更多
关键词 Non-alcoholic fatty liver disease Glucose-lowering drug META-ANALYSIS Dipeptidyl peptidase-4 inhibitor Sodium-glucose cotransporter 2 inhibitor Glucagon-like peptide-1 receptor agonist
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