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Parking choice behaviour analysis of rural residents based on the latent variable random forest model

Transportation Safety and Environment 2024年第3期6卷 167-180页

作者： Minqing zhu bo Zhao Hongjun Cui Sheng Yao Feng Xu School of Architecture and Art Design Hebei University of TechnologyTianjin 300130China School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China

The imbalance of rural parking supply and demand has a great impact on traffic congestion and environmental pollution,which has attracted the attention of many scholars as well as ***,most of the current research on parking choice focuses on urban business and residential areas rather than on rural parking choice behaviour,and focuses on the analysis of observable factors,ignoring the internal relationship with potential *** study considers the heterogeneity of individuals and uses the random forest(RF)algorithm to construct a model of rural residents’willingness to choose parking with both latent and explicit variables,to explore how much and in what ways individual characteristics and parking characteristics affect rural residents’parking choices,and to explore parking planning programmes and strategies that are truly applicable to rural *** results of the study suggest that the safety and convenience of the parking environment are key factors influencing the parking choice behaviour of rural residents,and can greatly improve the predictive accuracy of the parking willingness *** comparison,it is found that the application of the RF algorithm is also significantly better than the logit model in terms of prediction effect,indicating that there is a nonlinear effect among the factors influencing the parking choice behaviour of rural residents and that the RF model with the addition of latent variables provides a better explanatory ability for the study of the parking choice behaviour of rural residents.

关键词： rural residents parking choice random forest(RF) latent variable SEM-RF model

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Umbilical cord mesenchymal stem cell exosomes alleviate necrotizing enterocolitis in neonatal mice by regulating intestinal epithelial cells autophagy

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World Journal of Stem Cells 2024年第6期16卷 728-738页

作者： Lin zhu Lu He Wu Duan bo Yang Ning Li Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Division of Endocrinology Department of Internal MedicineQilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Shenzhen Research Institute of Shandong University Shenzhen 518000Guangdong ProvinceChina Institute of Organ Transplantation Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Department of Physical Education Heze UniversityHeze 274015Shandong ProvinceChina

BACKGROUND Necrotizing enterocolitis(NEC)is a severe gastrointestinal disease that affects premature *** mounting evidence supports the therapeutic effect of exosomes on NEC,the underlying mechanisms remain *** To investigate the mechanisms underlying the regulation of inflammatory response and intestinal barrier function by umbilical cord mesenchymal stem cell(UCMSCs)exosomes,as well as their potential in alleviating NEC in neonatal *** NEC was induced in 5-d-old C57BL/6 pups through hypoxia and gavage feeding of formula containing lipopolysaccharide(LPS),after which the mice received human UCMSC exosomes(hUCMSC-exos).The control mice were allowed to breastfeed with their *** tissues were collected from the mice and analyzed by histopathology and *** tissues were collected from NEC neonates and analyzed by *** biology and cell culture approaches were employed to study the related mechanisms in intestinal epithelial *** We found that autophagy is overactivated in intestinal epithelial cells during NEC,resulting in reduced expression of tight junction proteins and an increased inflammatory *** ability of hUCMSC-exos to ameliorate NEC in a mouse model was dependent on decreased intestinal *** also showed that hUCMSC-exos alleviate the inflammatory response and increase migration ability in intestinal epithelial cells induced by *** These results contribute to a better understanding of the protective mechanisms of hUCMSC-exos against NEC and provide a new theoretical and experimental foundation for NEC *** findings also enhance our understanding of the role of the autophagy mechanism in NEC,offering potential avenues for identifying new therapeutic targets.

关键词： Necrotizing enterocolitis Autophagy Umbilical cord mesenchymal stem cell Exosomes Intestinal epithelial cell Intestinal barrier function

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一种无人机用数字无刷电动推缸的设计

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电力电子技术 2020年第4期54卷 36-39页

作者：朱剑波中国空空导弹研究院河南洛阳471009

实现了一种无人机(UAV)用数字无刷电动推缸,采用TMS320F2812型数字信号处理器(DSP)作为控制核心,以线性可变差动变压(LVDT)器作为反馈装置,以无刷直流电动机作为伺服电机,以滚珠丝杠副+摇臂机构作为执行机构以实现力矩的传递、直线运动... 详细信息

实现了一种无人机(UAV)用数字无刷电动推缸,采用TMS320F2812型数字信号处理器(DSP)作为控制核心,以线性可变差动变压(LVDT)器作为反馈装置,以无刷直流电动机作为伺服电机,以滚珠丝杠副+摇臂机构作为执行机构以实现力矩的传递、直线运动和旋转转动的相互转化,实现了伺服系统的高实时性、高可靠性、高精度。试验测试结果表明,该系统对于1°/20 Hz输入信号的相位延迟为34.93°;对于10°阶跃的稳态误差达到0.08°;在20 N·m负载力矩加载条件下,角速度达到450.2°·s^1。

关键词：无刷直流电动机数字无刷电动推缸数字信号处理器

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A new interacting capillary bundle model on the multiphase flow in micropores of tight rocks

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Petroleum Science 2024年第2期21卷 1099-1112页

作者： Wen-Quan Deng Tian-bo Liang Wen-Zhong Wang Hao Liu Jun-Lin Wu Fu-jian Zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettability alteration by surfactants. Although the interacting capillary bundle(ICB) model shows potential in characterizing imbibition rates in different pores during wettability alteration, the existing ICB models neglect the influence of wettability and viscosity ratio on the imbibition behavior, making it difficult to accurately describe the oil-water imbibition behavior within the porous media. In this work,a new ICB mathematical model is established by introducing pressure balance without assuming the position of the leading front to comprehensively describe the imbibition behavior in a porous medium under different conditions, including gas-liquid spontaneous imbibition and oil-water *** the pore size distribution of a tight rock is known, this new model can predict the changes of water saturation during the displacement process in the tight rock, and also determine the imbibition rate in pores of different sizes. The water saturation profiles obtained from the new model are validated against the waterflooding simulation results from the CMG, while the imbibition rates calculated by the model are validated against the experimental observations of gas-liquid spontaneous imbibition. The good match above indicates the newly proposed model can show the water saturation profile at a macroscopic scale while capture the underlying physics of the multiphase flow in a porous medium at a microscopic scale. Simulation results obtained from this model indicate that both wettability and viscosity ratio can affect the sequence of fluid imbibition into pores of different sizes during the multiphase flow, where less-viscous wetting fluid is preferentially imbibed into larger pores while more-viscous wetting fluid tends to be imbibed into smaller pores. Fur

关键词： Imbibition Multiphase flow Tight rock Interacting capillary bundle model Wettability

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A dual-function selection system enables positive selection of multigene CRISPR mutants and negative selection of Cas9-free progeny in Arabidopsis

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aBIOTECH 2024年第2期5卷 140-150页

作者： Feng-zhu Wang Ying Bao Zhenxiang Li Xiangyu Xiong jian-Feng Li State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

The CRISPR/Cas9 technology revolutionizes targeted gene knockout in diverse organisms including ***,screening edited alleles,particularly those with multiplex editing,from herbicide-or antibiotic-resistant transgenic plants and segregating out the Cas9 transgene represent two laborious *** solutions to facilitate these processes rely on different selection ***,by taking advantage of the opposite functions of a D-amino acid oxidase(DAO)in detoxifying D-serine and in metabolizing non-toxic D-valine to a cytotoxic product,we develop a DAO-based selection system that simultaneously enables the enrichment of multigene edited alleles and elimination of Cas9-containing progeny in Arabidopsis *** five DAOs tested in Escherichia coli,the one encoded by Trigonopsis variabilis(TvDAO)could confer slightly stronger D-serine resistance than other *** expression of TvDAO in Arabidopsis allowed a clear distinction between transgenic and nontransgenic plants in both D-serine-conditioned positive selection and D-valine-conditioned negative *** a proof of concept,we combined CRISPR-induced single-strand annealing repair of a dead TvDAO with D-serine-based positive selection to help identify transgenic plants with multiplex editing,where D-serine-resistant plants exhibited considerably higher co-editing frequencies at three endogenous target genes than those selected by ***,D-valine-based negative selection successfully removed Cas9 and TvDAO transgenes from the survival offspring carrying inherited ***,this work provides a novel strategy to ease CRISPR mutant identification and Cas9 transgene elimination using a single selection marker,which promises more efficient and simplified multiplex CRISPR editing in plants.

关键词： CRISPR Genome editing D-amino acid oxidase Cas9-free Selection marker

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Analyses of fin ray types to detect strontium markers in juvenile blunt-snout bream Megalobrama amblycephala

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Ecological Processes 2024年第1期13卷 206-216页

作者： Yahua zhu Tao jiang Xiubao Chen Hongbo Liu Quinton Phelps jian Yang Wuxi Fisheries College Nanjing Agricultural University (WFCNAU) Laboratory of Fishery Microchemistry Freshwater Fisheries Research Center Chinese Academy of Fishery Sciences (FFRCCAFS) Department of Biology Missouri State University (DBMSU)

Background Restocking by introducing hatchery-reared fish into wild habitats aids in the restoration of fishery aquatic ecosystems and reefs to increase the abundance of fish resources, restore the ecological balance of water bodies, and enhance ecosystem functioning. Accurately, rapidly, and effectively evaluating the success of restocking using chemical markers（e.g., strontium [Sr]） remains challenging for fisheries management. Consequently, for nonlethal fish sampling, hard tissues, such as fin rays, have received increasing attention as a target for marking method. However, data on the differences in marking different types of fin rays remain limited. Therefore, we exposed juvenile blunt snout bream individuals（Megalobrama amblycephala） to 0（control group） or 800 mg/L of SrCl2·6H2O（marked group） for 5 days and transferred them into normal aerated water for post-immersion culture. We sampled their pectoral, dorsal, ventral, anal, and caudal fin rays. The Sr marks among the fin types were sampled at 0 and 20 days post-immersion and evaluated using an electron probe micro-analyzer（EPMA） for the five-day Sr/Ca ratios, along with line transect and Sr mapping *** Sr marking signatures were observed in all fin types in the marked group, with a success rate of up to 100%. Although marking efficiency varied among the different fin ray types, the highest Sr/Ca ratios were most often detected in the dorsal fin. Cross-sectional Sr concentration maps of all fin rays sampled showed high-Sr domains in the marked group; in contrast, the entire cross-sections of the control group displayed low Sr contents, indicating successful marking *** Fin ray Sr marking is a successful method for juvenile M. amblycephala, with the advantages of nonlethality and negligible sampling injuries, facilitating the rapid and effective evaluation of Sr marking in restocking M. amblycephala.

关键词： Megalobrama amblycephala Juvenile Fin ray Strontium marking Electron probe micro-analyzer

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大渡河某平原型水电站工程对地下水影响的数值模拟分析

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成都理工大学学报（自然科学版） 2013年第4期40卷 474-480页

作者：罗敏朱剑波任蕊四川省地质工程勘察院成都610072

利用数值模拟方法,预测大渡河某平原型水电站工程建设对地下水的影响,为工程建设提供参考依据。预测结果,工程建成后,设置的防渗墙阻挡了河水与阶地内地下水之间的水力联系,使右岸两个阶地形成较为封闭的水文地质单元,枯水期地下水位降... 详细信息

利用数值模拟方法,预测大渡河某平原型水电站工程建设对地下水的影响,为工程建设提供参考依据。预测结果,工程建成后,设置的防渗墙阻挡了河水与阶地内地下水之间的水力联系,使右岸两个阶地形成较为封闭的水文地质单元,枯水期地下水位降幅较大,相对于现状地下水位已下降的状态分别继续下降0.43～0.97m、0.47～1.59m,丰水期则在局部低洼地带可能出现内涝;左岸片区则影响较小。建议妥善解决村民饮用水问题,同时做好地表排水措施。

关键词：平原水库水电站数值模拟地下水

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A resonant high-pressure microsensor based on a composite pressure-sensitive mechanism of diaphragm bending and volume compression

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Microsystems & Nanoengineering 2024年第2期10卷 57-66页

作者： Pan Qian Zongze Yu Jie Yu Yulan Lu bo Xie jian Chen Deyong Chen Junbo Wang The State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing100049China

In this paper,a composite pressure-sensitive mechanism combining diaphragm bending and volume compression was developed for resonant pressure microsensors to achieve high-pressure measurements with excellent *** composite mechanism was explained,and the sensor structure was designed based on theoretical analysis and finite element *** all-silicon resonant high-pressure microsensor with multiple miniaturized cavities and dual resonators was developed,where dual resonators positioned in two resonant cavities with suitably different widths are used to perform opposite characteristics in pressure and the same characteristics at different temperatures,which can improve pressure sensitivities and realize temperature self-compensation by differential frequency *** microsensor was fabricated by microfabrication,and the experimental results showed that the sensor had an accuracy of±0.015%full scale(FS)in a pressure range of 0.1~100 MPa and a temperature range of−10~50℃.The pressure sensitivity of the differential frequency was 261.10 Hz/MPa(~2523 ppm/MPa)at a temperature of 20℃,and the temperature sensitivities of the dual resonators were−1.54 Hz/℃(~−14.5 ppm/℃)and−1.57 Hz/℃(~−15.6 ppm/℃)at a pressure of 2 *** differential output had an outstanding stability within±0.02 Hz under constant temperature and ***,this research provides a convenient solution for high-pressure measurements because of its advantages,namely,large range,excellent accuracy and stability.

关键词： stability resonant bending

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Ellagic Acid Enhances Antioxidant System Activity and Maintains the Quality of Strawberry Fruit during Storage

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Phyton-International Journal of Experimental botany 2024年第1期93卷 15-28页

作者： jian Chen Jing Zhang Gang Pan Dandan Huang Shuhua zhu College of Chemistry and Material Science Shandong Agricultural UniversityTaian271018China Agriculture and Rural Bureau of Penglai District Yantai265699China Laiyang Inspection and Testing Center Yantai265299China

Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improving the quality index of postharvest fruit have rarely been *** this experiment,the strawberries were soaked in 0,100,200,300,400,and 500 mg L^(−1) EA,respectively,and the influential EA on fruit quality and the antioxidant system of strawberries were *** with the control,EA treatment can reduce the browning degree and rotting rate of strawberry fruit during storage and augment the soluble solid content(SSC).EA treatment can also increase the content of related stuff and enzyme activity in antioxidant systems;the gene expression level of polyphenol oxidase(PPO)in strawberries treated with EA was always down-regulated,correspondingly,the expression of other antioxidant enzyme genes was *** the strawberry fruits treated with EA of different concentrations,300 mg L^(−1) EA had the best effect in the process of strawberry *** results suggested that the proper concentration of exogenous EA at 300 mg L−1 could maintain strawberries’quality and enhance the antioxidant system by improving the activities of antioxidative enzymes and the ascorbateglutathione(AsA-GSH)cycle during storage.

关键词： Strawberry ellagic acid antioxidative enzyme AsA-GSH cycle storage

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Single-atom Ni-N_(4) for enhanced electrochemical sensing

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Nano Research 2024年第8期17卷 7658-7664页

作者： zhuhui Qin bo Tang Guiru Zhang Chongqing zhu Kun jiang bowei Zhang Fu-Zhen Xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Interdisciplinary Research Center School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Single-atom catalysts(SACs)attract widespread attention in heterogeneous catalysis due to their maximum atomic utilization efficiency and unique physical and chemical ***,their applications in chemical sensing keep huge potential but remain ***,a Ni-N_(4)-C SAC was synthesized for the trace detection of dopamine(DA)and uric acid(UA).The Ni-N_(4)-C SAC exhibited superior sensing performance compared to the Ni *** detection range for DA and UA were 0.05–75μM and 5–90μM with detection limits of 0.027 and 0.82μM,*** functional theory(DFT)computations indicate that Ni-N_(4)-C has a lower reaction barrier during electrochemical process,indicating that the atomic Ni sites possess higher intrinsic activity than Ni ***,DA and UA show strong potential dependency on the Ni-N_(4)-C catalyst,indicating its applicability for their concurrent *** work extends the application of SACs in chemical sensing.

关键词： single-atom catalysts chemical sensing dopamine uric acid

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