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Evolution of a Late Pleistocene palaeolake in Dali Nor area of southeastern Inner Mongolia Plateau,China

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Geoscience Frontiers 2018年第1期9卷 223-237页

作者： Yuanhong lan Mingzhong tian Xujiao Zhang Xuefeng Wen Chunjing Kang School of Earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China College of Agriculture Guizhou UniversityGuiyang 550025China The Fourth Geological Exploration Institute of Henan Geology and Mineral Bureau Zhengzhou 450001China

Lithological,geochronological,granulometric,and scanning electron microscope(SEM)analyses of eight lacustrine outcrops indicate the existence of a large palaeolake in Dali Nor area during 149-24.6 ka(MIS5-3)and a small one in upstream of the Xilamulun River during 12.96-11.69 *** large palaeolake recorded its highest water level above 1300 m during the MIS3 and covered the whole Dali Nor basin and upstream of the Xilamulun River within an area of about 3000 km^***,the small palaeolake with a highest water level above 1200 m,covered an area of about 600 km^*** the reconstruction of palaeolake areas,this study also looked into the evolutionary process of the palaeolake during the Late *** data provide insights on the timing of appearance of the large palaeolakes and a better understanding of the mechanism responsible for variations in the environment conditions of dry lands in middle latitudes.

关键词： Late Pleistocene High lake level Dali Nor area Palaeolake

A Better Zn-Ion Storage Device:Recent Progress for Zn-Ion Hybrid Supercapacitors

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Nano-Micro Letters 2022年第4期14卷 158-206页

作者： Jialun jin Xiangshun Geng Qiang Chen tian-Ling Ren School of Integrated Circuits and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084People’s Republic of China College of Material Science and Engineering Zhejiang University of TechnologyHangzhou 310014People’s Republic of China

As a new generation of Zn-ion storage systems,Zn-ion hybrid supercapacitors(ZHSCs)garner tremendous interests recently from researchers due to the perfect integration of batteries and *** have excellent integration of high energy density and power density,which seamlessly bridges the gap between batteries and supercapacitors,becoming one of the most viable future options for large-scale equipment and portable electronic ***,the currently reported two configurations of ZHSCs and corresponding energy storage mechanisms still lack systematic ***,this review will be prudently organized from the perspectives of design strategies,electrode configurations,energy storage mechanisms,recent advances in electrode materials,electrolyte behaviors and further applications(micro or flexible devices)of *** synthesis processes and electrochemical properties of well-designed Zn anodes,capacitor-type electrodes and novel Zn-ion battery-type cathodes are comprehensively ***,a brief summary and outlook for the further development of ZHSCs are presented as *** review will provide timely access for researchers to the recent works regarding ZHSCs.

关键词： Zn-ion storage systems Zn-ion hybrid supercapacitors Carbon electrodes Zinc anodes Electrolytes

Characterization of a novel DUF1618 gene family in rice

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Journal of Integrative Plant Biology 2014年第2期56卷 151-158页

作者： lan Wang Rongxin Shen Le-tian Chen Yao-Guang Liu State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of Life Sciences South China Agricultural University College of Agriculture South China Agricultural University Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms College of Life Sciences South China Agricultural University

Domain of unknown function （DUF） proteins represent a number of gene families that encode functionally uncharacterized proteins in eukaryotes. For example, DUF1618 family members in plants possess a 56-199-amino acid conserved domain and this family has not been described previously. Here, we report the characterization of 121 DUF1618 genes identified in the rice genome. Based on phylogenetic analysis, the rice DUF1618 family was divided into two major groups, each group consisting of two clades. Most DUF1618 genes with close phylogenetic relationships are located in gene clusters on the chromosomes, indicating that gene duplications increased the number of DUF1618 genes. A search for DUF1618 genes in genomic and/or expressed sequence tag databases for 35 other plant species showed that DUF1618 genes are only present in several monocot plants, suggesting that DUF1618 is a new gene family that originated after the dicot-monocot divergence. Based on public microarray databases, most rice DUF1618 genes are expressed at relatively low levels. Further experimental analysis showed that the transcriptional levels of some DUF1618 genes varied in different cultivars, and some responded to stress and hormone conditions, suggesting their important roles for development and fitness in rice （Oryza sativa L.）.

关键词： DUF1618 domain phylogenetic analysis pollen fertility rice

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运动对大学生肠道菌群影响的系统综述

中国组织工程研究 2025年第11期29卷 2394-2401页

作者：刘昭志黄丽田浩冬李岚陈晓陶云飞彭莉西南大学体育学院重庆市400715 西南大学体育学院国家体育总局体质评价与运动机能监控重点实验室重庆市400715 山东中医药大学健康学院山东省济南市250000

背景:运动对肠道菌群的调节与人体健康密切相关,但肠道菌群涉及多方面因素影响,国内外研究尚缺乏有关运动对大学生肠道菌群影响的较为一致的证据。目的:探讨运动对大学生肠道菌群多样性和物种组成的影响。方法:通过系统检索PubMed、Web ... 详细信息

背景:运动对肠道菌群的调节与人体健康密切相关,但肠道菌群涉及多方面因素影响,国内外研究尚缺乏有关运动对大学生肠道菌群影响的较为一致的证据。目的:探讨运动对大学生肠道菌群多样性和物种组成的影响。方法:通过系统检索PubMed、Web of Science、Embase、Medline、Cochrane Library、中国知网、万方、维普数据库,筛选后纳入8篇实证研究,对其采用半定量的方法进行分析。结果与结论:①在运动改变大学生肠道菌群物种多样性方面,高强度间歇训练和太极拳运动均能显著提升大学生肠道菌群的物种多样性,而有氧运动对大学生肠道菌群多样性的提升效果不显著;②在运动影响肠道菌群物种组成方面,3种运动方式均能显著改变大学生肠道中菌群的组成结构,可以提高瘤胃球菌、普氏粪杆菌、布劳提亚菌等有益菌的丰度,降低埃希氏菌属等有害菌的丰度;相较于高强度间歇训练,有氧运动和太极拳运动引起了更多有益菌丰度的提升;③除肠道菌群特征的变化外,运动还可以改善大学生体成分、心肺功能以及执行功能等,这些健康效益与运动引起的菌群变化密切相关,这些菌群可通过代谢调节、屏障功能以及神经调节对机体产生健康效益;④虽然目前已有研究证实了运动与肠道菌群存在关联,但运动影响肠道菌群的机制尚未明确,同时定位与宿主健康相关的菌群是未来以肠道菌群为治疗靶点的关键,这些均值得学者进一步关注和探究。

关键词：运动干预大学生肠道菌群菌群多样性物种组成

Cosmological constraints on the Undulant Universe

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Research in Astronomy and Astrophysics 2010年第11期10卷 1109-1118页

作者： tian lan Yan Gong Hao-Yi Wan Tong-Jie Zhang Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Business Office Beijing Planetarium Beijing 100044 China Center for High Energy Physics Peking University Beijing 100871 China

We use the redshift Hubble parameter H（z） data derived from relative galaxy ages, distant type Ia supernovae （SNe Ia）, the Baryonic Acoustic Oscillation （BAO） peak, and the Cosmic Microwave Background （CMB） shift parameter data, to constrain cosmological parameters in the Undulant Universe. We marginalize the like- lihood functions over h by integrating the probability density 19 ∝ e-x^2/2. By using a Markov Chain Monte Carlo （MCMC） technique, we obtain the best fitting results and give the confidence regions in the b - Ωm0 plane. Then we compare their constraints. Our results show that the H（z） data play a similar role with the SNe Ia data in cosmological study. By presenting the independent and joint constraints, we find that the BAO and CMB data play very important roles in breaking the degeneracy compared with the H（z） and SNe Ia data alone. Combined with the BAO or CMB data, one can remarkably improve the constraints. The SNe Ia data sets constrain Ωm0 much tighter than the H（z） data sets, but the H（z） data sets constrain b much tighter than the SNe Ia data sets. All these results show that the Undulant Universe approaches the ACDM model. We expect more H（z） data to constrain cosmological parameters in the future.

关键词： cosmology observations - dark matter

Churn-Resilient Task Scheduling in a Tiered IoT Infrastructure

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China Communications 2019年第8期16卷 162-175页

作者： Jianhua Fan Xianglin Wei Tongxiang Wang tian lan Suresh Subramaniam Nanjing Telecommunication Technology Research Institute Nanjing210007China George Washington University Washington DC20052US

Cloud-as-the-center computing paradigms face multiple challenges in the 5G and Internet of Things scenarios, where the service requests are usually initiated by the end-user devices located at network edge and have rigid time constraints. Therefore, Fog computing, or mobile edge computing, is introduced as a promising solution to the service provision in the tiered IoT infrastructure to compensate the shortage of traditional cloud-only architecture. In this cloud-to-things continuum, several cloudlet or mobile edge server entities are placed at the access network to handle the task offloading and processing problems at the network edge. This raises the resource scheduling problem in this tiered system, which is vital for the promotion of the system efficiency. Therefore, in this paper, a scheduling mechanism for the cloudlets or fog nodes are presented, which takes the mobile tasks’ deadline and resources requirements at the same time while promoting the overall profit of the system. First, the problem at the cloudlet, to which IoT devices offload their tasks, is formulated as a multi-dimensional 0-1 knapsack problem. Second, based on ant colony optimization, a scheduling algorithm is presented which treat this problem as a subset selection problem. Third, to promote the performance of the system in the dynamic environments,a churn-refined algorithm is further put forward. A series of simulation experiments have shown that out proposal outperforms many state-of-the-art algorithms in both profit and guarantee ratio.

关键词： fog computing task scheduling deadline constrained internet of things ant colony optimization

SDH-FCOS:An Efficient Neural Network for Defect Detection in Urban Underground Pipelines

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Computers, Materials & Continua 2024年第1期78卷 633-652页

作者： Bin Zhou Bo Li Wenfei lan Congwen tian Wei Yao College of Computer Science South-Central Minzu UniversityWuhan430074China

Urban underground pipelines are an important infrastructure in cities,and timely investigation of problems in underground pipelines can help ensure the normal operation of *** to the growing demand for defect detection in urban underground pipelines,this study developed an improved defect detection method for urban underground pipelines based on fully convolutional one-stage object detector(FCOS),called spatial pyramid pooling-fast(SPPF)feature fusion and dual detection heads based on FCOS(SDH-FCOS)*** study improved the feature fusion component of the model network based on FCOS,introduced an SPPF network structure behind the last output feature layer of the backbone network,fused the local and global features,added a top-down path to accelerate the circulation of shallowinformation,and enriched the semantic information acquired by shallow *** ability of the model to detect objects with multiple morphologies was strengthened by introducing dual detection *** experimental results using an open dataset of underground pipes show that the proposed SDH-FCOS model can recognize underground pipe defects more accurately;the average accuracy was improved by 2.7% compared with the original FCOS model,reducing the leakage rate to a large extent and achieving real-time ***,our model achieved a good trade-off between accuracy and speed compared with other mainstream *** proved the effectiveness of the proposed model.

关键词： Urban underground pipelines defect detection SDH-FCOS feature fusion SPPF dual detection heads

Effect of nitrogen introduction methods on the microstructure and properties of gradient cemented carbides

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 709-716页

作者： tian-en Yang Ji Xiong lan Sun Zhi-xing Guo Ding Cao School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China

Gradient cemented carbides with the surface depleted in cubic phases were prepared following normal powder metallurgical *** zone formation and the influence of nitrogen introduction methods on the microstructure and performance of the alloys were *** results show that the simple one-step vacuum sintering technique is doable for producing gradient cemented *** structure formation is attributed to the gradient in nitrogen activity during sintering,but is independent from nitrogen introduced methods.A uniform carbon distribution is found throughout the ***,the transverse rupture strength of the cemented carbides can be increased by a gradient *** nitrogen carriers give the alloys distinguishing microstructure and mechanical properties,and a gradient alloy with ultrafine-TiC0.5N0.5 is found optimal.

关键词： gradient cemented carbide gradient methods nitrogen microstructure mechanical properties sintering

Assessment of the relationship between resilience and quality of life in patients with digestive cancer

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World Journal of Gastroenterology 2014年第48期20卷 18439-18444页

作者： Jun tian jin-Sheng Hong Department of Epidemiology and Health Statistics Fujian Medical University Department of Radiotherapy First Affiliated Hospital of Fujian Medical University

AIM: To study the relationship between resilience and quality of life (QOL) in patients with digestive cancer.

关键词： Resilience Psychological distress Fatigue Quality of life Path analysis Digestive cancer