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Gene Network Analysis and Functional Studies of Senescence-associated Genes Reveal Novel Regulators of Arabidopsis Leaf Senescence

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Journal of Integrative Plant Biology 2012年第8期54卷 526-539页

作者： Zhonahai li Jinying Peng Xing wen Hongwei Guo State Key Laboratory of Protein and Plant Gene Research College of Life SciencesPeking UniversityPeking-Tsinghua Center for Life SciencesBeijing 100871China

Plant leaf senescence has been recognized as the last phase of plant development, a highly ordered process regulated by genes known as senescence associated genes （SAGs）. However, the function of most of SAGs in regulating leaf senescence as well as regulators of those functionally known SAGs are still unclear. We have previously developed a curated database of genes potentially associated with leaf senescence, the Leaf Senescence Database （LSD）. In this study, we built gene networks to identify common regulators of leaf senescence in Arabidopsis thaliana using promoting or delaying senescence genes in LSD. Our results demonstrated that plant hormones cytokinin, auxin, nitric oxide as well as small molecules, such as Ca2＋, delay leaf senescence. By contrast, ethylene, ABA, SA and JA as well as small molecules, such as oxygen, promote leaf senescence, altogether supporting the idea that phytohormones play a critical role in regulating leaf senescence. Functional analysis of candidate SAGs in LSD revealed that a WRKY transcription factor WRKY75 and a Cys2/His2-type transcription factor AZF2 are positive regulators of leaf senescence and loss-of-function of WRKY75 or AZF2 delayed leaf senescence. We also found that silencing of a protein phosphatase, AtMKP2, promoted early senescence. Collectively, LSD can serve as a comprehensive resource for systematic study of the molecular mechanism of leaf senescence as well as offer candidate genes for functional analyses.

关键词： Arabidopsis leaf senescence SAG phytohormone systems biology.

Nanoscale ultraviolet photodetectors based on one- dimensional metal oxide nanostructures

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Nano Research 2015年第2期8卷 382-405页

作者： wei Tian Hao Lu liang li College of Physics Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology SoochowUniversity Suzhou 215006 China

Among the important optoelectronic devices, ultraviolet （UV） photodetectors show wide applications in fire monitoring, biological analysis, environmental sensors, space exploration, and UV irradiation detections. Research interest has focused on the utilization of one-dimensional （1D） metal oxide nanostructures to build advanced UV photodetectors through various processes. With large surface-to-volume ratio and well-controlled morphology and composition, 1D metal oxide nanostructures are regarded as promising candidates as components for building photodetectors with excellent sensitivity, superior quantum efficiency, and fast response speed. This article reviews the latest achievements with 1D metal oxide nanostructures reported over the past five years and their applications in UV light detection. It begins with an introduction of 1D metal oxide nanostructures, and the significance, key parameters and types of photo- detectors. Then we present several kinds of widely-studied 1D nanostructures and their photodetection performance, focusing on binary oxides with wide- bandgap （such as ZnO, SnO2, Ga203, Nb2Os, and WO3） and ternary oxides （such as Zn2SnO4, Zn2GeO4, and In2Ge2OT）. Finally, the review concludes with our perspectives and outlook on future research directions in this field.

关键词： metal oxide 1D nanostructures UV light photodetector nanodevices

Infrared Small Target Detection Algorithm Based on ISTD-CenterNet

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Computers, Materials & Continua 2023年第12期77卷 3511-3531页

作者： Ning li Shucai Huang Daozhi wei Air and Missile Defense College Air Force Engineering UniversityXi’an710051China

This paper proposes a real-time detection method to improve the Infrared small target detection CenterNet(ISTD-CenterNet)network for detecting small infrared targets in complex *** method eliminates the need for an anchor frame,addressing the issues of low accuracy and slow *** is used as the framework for feature extraction,and an ECBAM attention module is added to each stage branch for intelligent identification of the positions of small targets and significant objects.A scale enhancement module is also added to obtain a high-level semantic representation and fine-resolution prediction map for the entire infrared ***,an improved sensory field enhancement module is designed to leverage semantic information in low-resolution feature maps,and a convolutional attention mechanism module is used to increase network stability and convergence *** experiments conducted on the infrared small target data set *** experiments show that compared to the benchmark network CenterNet-HRNet,the proposed ISTD-CenterNet improves the recall by 22.85%and the detection accuracy by 13.36%.Compared to the state-of-the-art YOLOv5small,the ISTD-CenterNet recall is improved by 5.88%,the detection precision is improved by 2.33%,and the detection frame rate is 48.94 frames/sec,which realizes the accurate real-time detection of small infrared targets.

关键词： Infrared small target detection CenterNet data enhancement feature enhancement attention mechanism

A Transductive Scheme Based Inference Techniques for Network Forensic Analysis

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China Communications 2015年第2期12卷 167-176页

作者： TIAN Zhihong JIANG wei li Yang Harbin Institute of Technology College of Computer Science Beijing University of Technology School of Computer National University of Defense Technology China International Capital Corporation limited

Network forensics is a security infrastructure,and becomes the research focus of forensic *** many challenges still exist in conducting network forensics:network has produced large amounts of data;the comprehensibility of evidence extracting from collected data;the efficiency of evidence analysis methods,*** solve these problems,in this paper we develop a network intrusion forensics system based on transductive scheme that can detect and analyze efficiently computer crime in networked environments,and extract digital evidence *** the end of the paper,we evaluate our method on a series of experiments on KDD Cup 1999 *** results demonstrate that our methods are actually effective for real-time network forensics,and can provide comprehensible aid for a forensic expert.

关键词： network forensics transductive scheme security digital evidence

Application of power law to vertical distribution of longshore currents

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Water Science and Engineering 2019年第1期12卷 73-83页

作者： Zhen-wei Zhang Zhi-li Zou School of Civil Engineering and Architecture Xiamen University of Technology Xiamen 361021 China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

The vertical profiles of longshore currents have been examined experimentally over plane and barred beaches. In most cases, the vertical profiles of longshore currents are expressed by the logarithmic law. The power law is not commonly used to describe the profile of longshore currents. In this paper, however, a power-type formula is proposed to describe the vertical profiles of longshore currents. The formula has two parameters: the power law index (a) and the depth-averaged velocity. Based on previous studies, power law indices were set as a=1/10 and a=1/7. Depth-averaged velocity can be obtained through measurement. The fitting of the measured velocity profiles to a=1/10 and a=1/7 was assessed for the vertical longshore profiles. The vertical profile of longshore currents is well described by the power-type formula with a=1/10 for a plane beach. However, for a barred beach, different values of a needed to be used for different regions. For the region from the bar trough to the offshore side of the bar crest, the vertical profiles of longshore currents given by the power-type formula with a=1/10 and a=1/7 fit the data well. However, the fit was slightly better with a=1/10 than that with a=1/7. For the data over the trough region of cross-shore distribution of the depth-averaged longshore currents, the power formula with a=1/3 provided a good fit. The formulas with a=1/10 and a=1/7 were further examined using published data from four sources covering laboratory and field experiments. The results indicate that the power-type formula fits the data well for the laboratory and field data with a=1/10.

关键词： Waves Coast Logarithmic law Power law Surf zone

Rounded Data Analysis Based on Multi-Layer Ranked Set Sampling

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2507-2518页

作者： wei Ming li Zhi Dong BAI KLMIB and School of Mathematics and Systems Science Beijing University of Aeronautics and Astronautics Beijing 100191 P. R. China Key Laboratory for Applied Statistics of MOE and School of Mathematics and Statistics Northeast Normal University Changchun 130024 P. R. China

Observations of sampling are often subject to rounding, but are modeled as though they were unrounded. This paper examines the impact of rounding errors on parameter estimation with multi-layer ranked set sampling. It shows that the rounding errors seriously distort the behavior of covariance matrix estimate, and lead to inconsistent estimation. Taking this into account, we present a new approach to implement the estimation for this model, and further establish the strong consistency and asymptotic normality of the proposed estimators. Simulation experiments show that our estimates based on rounded multi-layer ranked set sampling are always more efficient than those based on rounded simple random sampling.

关键词： Rounding error multi-layer ranked set sampling work likelihood method

Effect of Potassium on Ultrastructure of Maize Stalk Pith and Young Root and Their Relation to Stalk Rot Resistance

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Agricultural Sciences in China 2010年第10期9卷 1467-1474页

作者： li wen-juan HE Ping JIN Ji-yun Key Laboratory of Plant Nutrition and Nutrient Cycling Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

To study the mechanism of potassium （K） application on improvement of maize resistance to stalk rot at cellular level, scanning electron microscope and transmission electron microscope were used to observe the effect of K on the ultrastructure of maize stalk pith tissue and young root tip cell influenced by K and pathogen. In K deficient treatment, parenchyma cells of stalk pith had abnormal structure, and the cell wall between upper and lower adjacent cell was damaged, resulting in the loss of connections between vascular cells and insufficient supporting capacity. However, an improved K nutrition helped to keep a quite tight arrangement of root cell with thick cell wall, and prevent the invasion of pathogen effectively. Moreover, K treated root cell had abundant golgi apparatus, which could excrete large amount of secretions to degrade mycelium. Papillary and highly electronic intensity dot were accumulated at the invading point to prevent the deveJopment of the mycelium. Improved K nutrition could increase the resistant ability of maize plant to stalk rot, through keeping cell structure stability, preventing the expansion of intracellular space to reduce the chances of pathogen invasions, and through reinforcing cell wall and formation of intercellular and intracellular material to restrict further development of pathogen in host cell.

关键词： potassium (K) maize stalk rot ultrastructure disease resistance

Research hotspots and trends in gut microbiota and nonalcoholic fatty liver disease: A bibliometric study

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World Journal of Hepatology 2025年第1期17卷 132-149页

作者： Cai-Yun Huang Zhong-Zhi Luo wei-Ping Huang li-Ping lin You-Ting Yao Han-Xu Zhuang Qiu-Yong Xu Ya-Dong Lai Department of Gastroenterology Zhangzhou Affiliated Hospital of Fujian Medical UniversityZhangzhou 363000Fujian ProvinceChina Department of Electrocardiogram Zhangzhou Affiliated Hospital of Fujian Medical UniversityZhangzhou 363000Fujian ProvinceChina

BACKGROUND Recent research indicates that the intestinal microbial community,known as the gut microbiota,may play a crucial role in the pathogenesis of nonalcoholic fatty liver disease(NAFLD).To understand this relationship,this study used a compre-hensive bibliometric analysis to explore and analyze the currently little-known connection between gut microbiota and NAFLD,as well as new findings and possible future pathways in this *** To provide an in-depth analysis of the current focus issues and research deve-lopments on the interaction between gut microbiota and *** In this study,all data were collected from the Web of Science Core Collection,and the related searches were completed on one day(February 21,2024).The data were stored in plain text format to facilitate subsequent *** 1.6.20 and CiteSpace 6.1R6 Basic were used for knowledge graph construction and bibliometric *** The study included a total of 1256 articles published from 2013 to 2023,and the number of published papers demonstrated an upward trend,reaching a peak in the last two *** University of California,San Diego held the highest citation count,while Shanghai University of Traditional Chinese Medicine in China led in the number of published *** journal"Nutrients"had the highest publication count,while"Hepatology"was the most frequently *** Korean author Suk Ki Tae was the most prolific *** co-cited keyword cluster labels revealed ten major clusters,namely cortisol,endothelial dysfunction,carbohydrate metabolism,myocardial infarction,non-alcoholic steatohepatitis,lipotoxicity,glucagon-like peptide-1,non-islet dependent,ethnicity,and *** outbreak analysis highlighted metabolic syndrome,hepatic steatosis,insulin resistance,hepatocellular carcinoma,cardiovascular disease,intestinal permeability,and intestinal bacterial overgrowth as prominent areas of intense *** Through the quantitative analysis of r

关键词： Gut microbiota Nonalcoholic fatty liver disease Bibliometric Knowledge maps VOSviewer Citespace

A simple approach for determining the preload of a wire race ball bearing

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第7期11卷 511-519页

作者： Xiao-biao SHAN li-li WANG Tao XIE wei-shan CHEN 1School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China College of Science Northeast Forestry University Harbin 150040 China

Wire race ball bearings have been widely used in high-tech weapons. The preload of a wire race ball bearing is crucial in engineering applications. In this study, a more effective approach is proposed for exact determination of the wire race ball bearing preload. A new mathematical model of the preload and the starting torque of the wire race ball bearing was built using the theorem of the 3D rolling friction resistance and the non-conforming contact theory. Employing a wire race ball bearing with a 1000 mm diameter used in a specific type of aircraft simulating rotary table, the numerical analysis in MATLAB～ showed that the preload magnitude can be controlled in the range of 130–140 μm. As verification, the experimental results were in agreement with the theoretical results, and confirm the feasibility of this method. This new approach is more exact in the preload range of 10–158 μm than that computed by the numerical method reported in our previous work (Shan et al., 2007b). This implies that the present method contributes to more effectively preventing rolling noise, overturning moments and wear of the wire race ball bearing. The current research provides critical technical support for the engineering application of wire race ball bearings with large diameters.

关键词： Wire race ball bearing Rolling friction Starting torque Contact interface