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World Journal of Clinical Cases 2024年第9期12卷 1606-1621页

作者： yu-yi yuan Hui Wu Qian-yun Chen Heng Fan Bo Shuai Department of Integrated Traditional Chinese and Western Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Circular RNAs(circRNAs)are involved in the pathogenesis of many diseases through competing endogenous RNA(ceRNA)regulatory *** To investigate a circRNA-related ceRNA regulatory network and a new predictive model by circRNA to understand the diagnostic mechanism of circRNAs in ulcerative colitis(UC).METHODS We obtained gene expression profiles of circRNAs,miRNAs,and mRNAs in UC from the Gene Expression Omnibus *** circRNA-miRNA-mRNA network was constructed based on circRNA-miRNA and miRNA-mRNA *** enrichment analysis was performed to identify the biological mechanisms involved in *** identified the most relevant differential circRNAs for diagnosing UC and constructed a new predictive nomogram,whose efficacy was tested with the C-index,receiver operating characteristic curve(ROC),and decision curve analysis(DCA).RESULTS A circRNA-miRNA-mRNA regulatory network was obtained,containing 12 circRNAs,three miRNAs,and 38 *** optimal prognostic-related differentially expressed circRNAs,hsa_circ_0085323 and hsa_circ_0036906,were included to construct a predictive *** model showed good discrimination,with a C-index of 1(>0.9,high accuracy).ROC and DCA suggested that the nomogram had a beneficial diagnostic *** This novel predictive nomogram incorporating hsa_circ_0085323 and hsa_circ_0036906 can be conveniently used to predict the risk of *** circRNa-miRNA-mRNA network in UC could be more clinically significant.

关键词： Circular RNAs RNA regulatory network Ulcerative colitis New predictive model Bioinformatics Diagnose

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林业资源保护和森林草原防火技术探析

园艺与种苗 2024年第7期44卷 51-52页

作者：易玉媛甘肃祁连山国家级自然保护区管护中心寺大隆自然保护站甘肃张掖734000

林业资源保护和森林草原防火技术是当今社会面临的重要议题之一,全球极端天气频发、森林覆盖率不断增加、人类活动扩张等因素对森林生态系统造成了巨大的威胁,保护森林资源和有效预防森林火灾的技术是至关重要的。该文详述了林业资源保... 详细信息

林业资源保护和森林草原防火技术是当今社会面临的重要议题之一,全球极端天气频发、森林覆盖率不断增加、人类活动扩张等因素对森林生态系统造成了巨大的威胁,保护森林资源和有效预防森林火灾的技术是至关重要的。该文详述了林业资源保护和森林草原防火技术的重要性,并对有效应对林业资源保护和森林火灾问题提供理论和实践指导。

关键词：资源保护森林防火草原防火

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祁连山青海云杉林下苔藓层持水及截留特征

兰州大学学报（自然科学版） 2024年第1期60卷 60-67页

作者：周碧莲顾继雄易玉媛赵传燕兰州大学草地农业科技学院草地农业生态系统国家重点实验室兰州730020 甘肃祁连山国家级自然保护区管理局甘肃张掖734000

为了探究祁连山青海云杉林下苔藓层的水文截留特性及其对土壤层水文功能的影响,设置不同坡度因子界定自然降雨条件下对土壤层水文功能的影响,研究祁连山青海云杉样地内苔藓层蓄积量、最大持水量和吸水速率等水文特征参数.结果表明,在自... 详细信息

为了探究祁连山青海云杉林下苔藓层的水文截留特性及其对土壤层水文功能的影响,设置不同坡度因子界定自然降雨条件下对土壤层水文功能的影响,研究祁连山青海云杉样地内苔藓层蓄积量、最大持水量和吸水速率等水文特征参数.结果表明,在自然降雨事件中,青海云杉样地的苔藓层在坡度为43°开始补充给土壤水分的降雨阈值最大(14.3 mm);在0°时开始补充给土壤水分的降雨阈值最小(10.7 mm),说明坡度会对苔藓植物的持水能力产生影响.林下苔藓层持水量随浸泡时间的延长而增加,其规律遵循对数方程W=k ln(t)+p.苔藓层吸水速率随浸泡时间延长按方程V=ktb的趋势下降.在模拟小降雨强度条件下,苔藓层最大持水量随降雨强度的增加而升高,最大持水量均高于浸泡法测定值的80%.

关键词：山羽藓坡度持水能力祁连山

Study of Flow and Heat Transfer in an Ejector-Driven Swirl Anti-Icing Chamber

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Fluid Dynamics & Materials Processing 2024年第5期20卷 989-1014页

作者： yi Tu yuan Wu yu Zeng Hunan University of Arts and Sciences Hunan Key Laboratory of Distributed Electric Propulsion Vehicle Control TechnologyChangde415000China Liaoning Provincial Key Laboratory of Aircraft Ice Protection AVIC Aerodynamics Research InstituteShenyang110034China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic *** Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annular chamber to heat the engine inlet lip surface and prevent *** study employs a validated Computational Fluid Dynamics(CFD)approach to study the impact of key geometric parameters of this system on flow and heat transfer characteristics within the anti-icing ***,the entropy generation rate and exergy efficiency are analyzed to assess the energy utilization in the *** research findings indicate that,within the considered flow range,reducing the nozzle specific areaφfrom 0.03061 to 0.01083 can enhance the ejection coefficient by over 60.7%.This enhancement increases the air circulating rate,thereby intensifying convective heat transfer within the SAI ***,the reduction inφalso leads to a significant increase in the required bleed air pressure and a higher entropy generation rate,indicating lower exergy *** nozzle angleθnotably affects the distribution of hot and cold spots on the lip surface of the SAI ***θfrom 0°to 20°reduces the maximum temperature difference on the anti-icing chamber surface by 60 K.

关键词： Swirl anti-icing heat transfer exergy efficiency hot and cold spot aircraft engine

A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： Huan yuan San-yi yuan Jie Wu Wen-Jing Sang yu-He Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

Simultaneously enhanced electrochemical performance and air stability of Ni-rich cathode with a modified washing process

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Rare Metals 2024年第1期43卷 87-97页

作者： Ben-Rui Hu ying-yi yuan yu-Cheng Wang Xun-Hui Xiong School of Environment and Energy Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510640China

Water washing has been regarded as one of the most effective strategies to remove surface residual lithium of nickel-rich layered oxides for lithium-ion batteries(LIBs).However,the loss of lattice lithium during the water washing process deteriorates the electrochemical performances and air ***,washing the LiNi_(0.90)Co_(0.05)Al_(0.02)O_(2)(NCA) with ammonium dihydrogen phosphate(NH_(4)H_(2)PO_(4)) solution has been proposed to simultaneously enhance electrochemical performances and air stability,in which in-situ generated Li_(3)PO_(4) coating layer on surface of NCA can suppress the loss of lattice ***,as a fast ionic conductor,Li_(3)PO_(4) coating layer on NCA can prevent the direct contact with electrolyte/*** a result,the NH_(4)H_(2)PO_(4) solution washed NCA cathode can deliver a high capacity of131.9 mAh·g^(-1) at 10.0C rate as well as impressive cycle stability with a capacity retention of 83.1% after 100 cycles at 1.0C,much higher than those of water washed NCA(WS-NCA) *** exposed in air for 7 days,the NH_(4)H_(2)PO_(4) solution washed NCA electrode can more effectively maintain the structural integrity as well as the electrochemical performances than water-washed *** work provides a simple and effective approach to enhance the cycle stability and air stability of Nickel-rich cathode materials.

关键词： Layered Ni-rich cathode Residual lithium Li_(3)PO_(4)coating Rate performance Air stability

A Symmetric-Actuating Linear Piezoceramic Ultrasonic Motor Capable of Producing a Scissoring Effect

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Research 2024年第1期2023卷 571-581页

作者： Zhanmiao Li Xingyu yi Rongqi Zhu Zhonghui yu Xiaoting yuan MohammadJavad PourhosseiniAsl Shuxiang Dong School of Materials Science and Engineering Peking UniversityBeijing 100871China College of Mechatronics and Control Engineering and Institute for Advanced StudyShenzhen UniversityShenzhen 518051China

Conventionally,to produce a linear motion,one motor’s stator is employed to drive one runner moving forward or *** far,there is almost no report of one electromechanical motor or piezoelectric ultrasonic motor that can directly generate two symmetrical linear motions,while this function is desired for precise scissoring and grasping in the minimally invasive surgery ***,we report a brandnew symmetric-actuating linear piezoceramic ultrasonic motor capable of generating symmetrical linear motions of two outputs directly without additional mechanical transmission *** key component of the motor is an(2×3)arrayed piezoceramic bar stator operating in the coupled resonant mode of the first longitudinal(L_(1))and third bending(B_(3))modes,leading to symmetric elliptical vibration trajectories at its two ends.A pair of microsurgical scissors is used as the end-effector,demonstrating a very promising future for high-precision microsurgical operations.

关键词： field symmetric backward

Nature-inspired design of droplet-synthesized polymeric nanoelectrode for photoelectrochemical microRNA sensing within single cells

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Science Bulletin 2024年第2期69卷 159-162页

作者： Si-yuan yu yi-Li Liu Zheng Li Dechen Jiang Jing-Juan Xu Hong-yuan Chen Wei-Wei Zhao State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Nanoelectrodes have been shown to be powerful tools for nanoscopic research on single entities,deepening the understanding of heterogeneity and stochastics for single molecules,nanoparticles and cells[1–3].However,despite their importance,current nanoelectrode preparations are highly restrained to flame/electrochemical etching,metal sputtering,electrochemical deposition,etc.[3],resulting in a limited range of materials(mainly gold,platinum and carbon)for potential-resolved detection of redox-active species(Table S1 online).The enrichment of preparation methods to introduce novel materials and mechanisms should prove significant for the development of nanoelectrodes.

关键词： electrode deepening restrained

Coordinated Voltage Control of Distribution Network ConsideringMultiple Types of Electric Vehicles

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Energy Engineering 2024年第2期121卷 377-404页

作者： Liang Liu Guangda Xu yuan Zhao yi Lu yu Li Jing Gao State Grid Jibei Electric Power Research Institute(North China Electric Power Research Institute Co. Ltd.)Beijing100045China

The couple between the power network and the transportation network(TN)is deepening gradually with the increasing penetration rate of electric vehicles(EV),which also poses a great challenge to the traditional voltage control *** this paper,we propose a coordinated voltage control strategy for the active distribution networks considering multiple types of *** the first stage,the action of on-load tap changer and capacitor banks,etc.,are determined by optimal power flow calculation,and the node electricity price is also determined based on dynamic time-of-use tariff *** the second stage,multiple operating scenarios of multiple types of EVs such as cabs,private cars and buses are considered,and the scheduling results of each EV are solved by building an optimization model based on constraints such as queuing theory,Floyd-Warshall algorithm and traffic flow *** the third stage,the output power of photovoltaic and energy storage systems is fine-tuned in the normal control *** charging power of EVs is also regulated in the emergency control mode to reduce the voltage deviation,and the amount of regulation is calculated based on the fair voltage control mode of ***,we test the modified IEEE 33-bus distribution system coupled with the 24-bus Beijing *** simulation results show that the proposed scheme can mitigate voltage violations well.

关键词： Electric vehicle transportation network voltage control queuing theory

A multi-mechanism numerical simulation model for CO_(2)-EOR and storage in fractured shale oil reservoirs

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Petroleum Science 2024年第3期21卷 1814-1828页

作者： yuan-Zheng Wang Ren-yi Cao Zhi-Hao Jia Bin-yu Wang Ming Ma Lin-Song Cheng College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China John&Willie Leone Department of Energy&Mineral Engineering The Pennsylvania State UniversityUniversity Park16802PA.USA

Under the policy background and advocacy of carbon capture,utilization,and storage(CCUS),CO_(2)-EOR has become a promising direction in the shale oil reservoir *** multi-scale pore structure distribution and fracture structure lead to complex multiphase flow,comprehensively considering multiple mechanisms is crucial for development and CO_(2) storage in fractured shale *** this paper,a multi-mechanism coupled model is developed by *** to the traditional Eclipse300 and MATLAB Reservoir Simulation Toolbox(MRST),this model considers the impact of pore structure on fluid phase behavior by the modified Peng—Robinson equation of state(PR-EOS),and the effect simultaneously radiate to Maxwell—Stefan(M—S)diffusion,stress sensitivity,the nano-confinement(NC)***,a modified embedded discrete fracture model(EDFM)is used to model the complex fractures,which optimizes connection types and half-transmissibility calculation approaches between non-neighboring connections(NNCs).The full implicit equation adopts the finite volume method(FVM)and Newton—Raphson iteration for discretization and *** model verification with the Eclipse300 and MRST is *** results show that the interaction between the mechanisms significantly affects the production performance and storage *** effect of molecular diffusion may be overestimated in oil-dominated(liquid-dominated)shale *** well spacing and injection gas rate are the most crucial factors affecting the production by sensitivity ***,the potential gas invasion risk is *** model provides a reliable theoretical basis for CO_(2)-EOR and sequestration in shale oil reservoirs.

关键词： CO_(2)-EOR CO_(2)storage Shale oil reservoir Complex fracture model Multiple mechanisms