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A New Perspective on Understanding the Reduced Spring Dust Storm Frequency in Inner Mongolia, China

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International Journal of Disaster Risk Science 2015年第3期6卷 216-225页

作者： Ning li li guo Bihang Fan State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Key Laboratory of Environmental Change and Natural Disasters Ministry of Education Beijing Normal University College of Global Change and Earth System Science Beijing Normal University

Spatiotemporal patterns of dust storms are affected by climate change through changes in convective instability, regional meteorological characteristics, and local sediment supply. linking dust storm dynamics to climate change helps the understanding of what controls the initiation of dust storms, and assists the prediction of future dust storm occurrence. This study examines the temporal dynamics of spring dust storms in Inner Mongolia, a major dust source area in East Asia. We found that severe spring dust storms have significantly declined from1954 to 2007. Four dust storm types showed similar decreasing trends from 2001 to 2012. This change in spring dust storm dynamics is attributed to the shift in vegetation green-up dates based on the analysis of a satellite derived vegetation index. Earlier vegetation green-up has a dampening effect on spring dust storms. Suitable environmental conditions for vegetation green-up hinder the emergence of dust storms. This study expands our understanding of the dynamics of spring dust storms in the changing climate through a new perspective on vegetation phenology in the spring.

关键词： Climate change Dust storm dynamics Green-up date Inner Mongolia Vegetation phenology

Sodium dehydroacetate treatment prolongs the shelf-life of'Kyoho'grape by regulating oxidative stress and DNA methylation

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Journal of Integrative Agriculture 2022年第5期21卷 1525-1533页

作者： guo Da-long liU Hai-nan WANG Zhen-guang guo li-li ZHANG guo-hai College of Horticulture and Plant Protection Henan University of Science and TechnologyLuoyang 471023P.R.China Henan Engineering Technology Research Center of Quality Regulation and Controlling of Horticultural Plants Luoyang 471023P.R.China

In this study,we tested the ability of sodium dehydroacetate(SD)to extend the shelf-life of‘Kyoho’*** the different concentrations of SD tested(0,0.01,0.1 and 1.0 mmol L^(-1)),0.01 mmol L^(-1) SD was the most effective in prolonging the shelf-life of‘Kyoho’*** with the control,the weight loss rate,browning index and hydrogen peroxide(H_(2)O_(2))and malonaldehyde contents were significantly lower in the 0.01 mmol L^(-1) SD treatment,whereas the healthy berry rate,berry firmness,total soluble solids(TSS)content,ascorbic acid content and superoxide dismutase(SOD)activity were significantly *** addition,an analysis of‘Kyoho’grape DNA using methylation sensitive amplification polymorphism(MSAP)markers showed that the average DNA methylation level was significantly higher in the 0.01 mmol L^(-1) SD treatment than in the ***,these results indicate that 0.01 mmol L^(-1) SD could be used to extend the shelf-life of‘Kyoho’***,a strong connection between reactive oxygen species(ROS)metabolism and DNA methylation change during storage was revealed.

关键词： grape sodium dehydroacetate DNA methylation MSAP shelf-life

openGauss: An Enterprise-Grade Open-Source Database System

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JOURNAL OF COMPUTER SCIENCE AND TECHNOLOGY 2024年第5期39卷 1007-1028页

作者： li, guo-liang Wang, Jiang Chen, guo Tsinghua Univ Dept Comp Sci Beijing 100084 Peoples R China Huawei Technol Co Ltd Beijing 100088 Peoples R China China Mobile Informat Technol Ctr Beijing 100027 Peoples R China

We have built openGauss, an enterprise-grade open-source database system. openGauss has fulfilled its design goal of high performance, high availability, high security, and high intelligence. For high performance, it leverages NUMA (non-uniform memory access)-aware data access among multiple cores to enable efficient concurrent transaction processing, and symmetric multi-processing to make use of parallel processing resources adaptively. Moreover, memory-optimized tables (MOTs) are designed to put everything in memory. For high availability, a three-tier pooling architecture that shares storage among the master and standby instances is proposed to achieve availability at 99.99%, containing both a distributed memory service (DMS) and a distributed storage service (DSS). For high security, it is a fully encrypted database with safe storage features, efficient complex querying, and tamper-proof. For high intelligence, an AI-based optimizer in the kernel and a self-driving platform named DBMind are demonstrated to achieve better performance and greater user-friendliness. openGauss has served over 150 enterprises and institutions since its release in 2020. We share the lessons we learned from its development and operation, and our customers.

关键词： database system open-source high performance storage engine

IC Cloud: Enabling Compositional Cloud

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International Journal of Automation and computing 2011年第3期8卷 269-279页

作者： Yi-Ke guo li guo Department of Computing Imperial College London London SW7 2BZ UK

Cloud computing has attracted great interest from both academic and industrial communities. Different paradigms, architectures and applications based on the concept of cloud have emerged. Although many of them have been quite successful, efforts are mainly focusing on the study and implementation of particular setups. However, a generic and more flexible solution for cloud construction is missing. In this paper, we present a composition-based approach for cloud computing （compositional cloud） using Imperial College Cloud （IC Cloud） as a demonstration example. Instead of studying a specific cloud computing system, our approach aims to enable a generic framework where wrious cloud computing architectures and implementation strategies can be systematically studied. With our approach, cloud computing providers/adopters are able to design and compose their own systems in a quick and flexible manner. Cloud computing systems will no longer be in fixed shapes but will be dynamic and adjustable according to the requirements of different application domains.

关键词： Cloud computing compositional cloud infrastructure as a service (IaaS) cloud service cloud elasticity.

Breaking the final barrier in reproductive animal cloning: macaque monkeys cloned

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National Science Review 2018年第3期5卷 301-303页

作者： Hongjun Song guo-li Ming Department of Neuroscience and Mahoney Institute for Neurosciences Department of Cell and Developmental Biology Institute for Regenerative Medicine University of Pennsylvania

Animal models are essential in research aiming to understand human biology and diseases,yet far too often clinical trials fail with drugs and therapeutic approaches that have been developed through,tested and built up... 详细信息

关键词： Breaking the final barrier in reproductive animal cloning macaque monkeys cloned

How to co-add images? I. A new iterative method for image reconstruction of dithered observations

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Research in Astronomy and Astrophysics 2017年第10期17卷 1-14页

作者： Lei Wang guo-liang li Purple Mountain Observatory Chinese Academy of Sciences

By employing the previous Voronoi approach and replacing its nearest neighbor approx- imation with Drizzle in iterative signal extraction, we develop a fast iterative Drizzle algorithm, namedfiDrizzle, to reconstruct the underlying band-limited image from undersampled dithered frames. Compared with the existing iDrizzle, the new algorithm improves rate of convergence and accelerates the computational speed. Moreover, under the same conditions （e.g. the same number of dithers and iterations）, fiDrizzle can make a better quality reconstruction than iDrizzle, due to the newly discov- ered High Sampling caused Decelerating Convergence （HSDC） effect in the iterative signal extraction *** demonstrates its powerful ability to perform image deconvolution from undersampled dithers.

关键词： techniques: image processing -- methods: observational -- stars: imaging -- planets andsatellites: detection -- gravitational lensing

Acute pulmonary embolism originating from upper limb venous thrombosis following breast cancer surgery:Two case reports

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World Journal of Clinical Cases 2022年第21期10卷 7445-7450页

作者： Yan Duan guo-li Wang Xin guo li-li Yang Fu-guo Tian Department of Critical Care Medicine Shanxi Provincial Cancer HospitalTaiyuan 030013Shanxi ProvinceChina Breast Diagnosis and Treatment Center Shanxi Provincial Cancer HospitalTaiyuan 030013Shanxi ProvinceChina

BACKGROUND Upper limb venous thrombosis(ULVT)is rarer than lower-extremity deep venous thrombosis,and is related to Paget-Schroetter syndrome,central venous catheterization,and *** are few reports of pulmonary embolism(PE)from upper-extremity vein thrombosis due to ***,we report two cases of PE that originated from upper limb venous thrombosis on the surgical side in two patients undergoing modified radical mastectomy for breast *** cases challenge the traditional theory that PE originate only from the lower *** SUMMARY We describe two female patients,aged 68 and 65 years,respectively,who had undergone modified radical mastectomy for breast *** did not have a central venous catheter and did not undergo preoperative neoadjuvant *** were transferred to the intensive care unit due to symptomatic PE on the first day after *** Doppler ultrasound identified fresh thrombosis in their upper limb veins,which was the presumed source of the *** all received anticoagulation therapy,and one of them experienced bleeding that required discontinuation of the ***,they were discharged in stable *** ULVT as a source of PE after breast cancer surgery cannot be ignored.

关键词： Pulmonary embolism Upper limb venous thrombosis Modified radical mastectomy for breast Case report

Large-eddy simulation of circular cylinder flow at subcritical Reynolds number:Turbulent wake and sound radiation

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Acta Mechanica Sinica 2016年第1期32卷 1-11页

作者： li guo Xing Zhang guowei He China Academy of Aerospace Aerodynamics Beijing 100074China State Key Laboratory of Non-linear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

The flows past a number 3900 are simulated circular cylinder at Reynolds using large-eddy simulation （LES） and the far-field sound is calculated from the LES results. A low dissipation energy-conserving finite volume scheme is used to discretize the incompressible Navier- Stokes equations. The dynamic global coefficient version of the Vreman＇s subgrid scale （SGS） model is used to com- pute the sub-grid stresses. Curie＇s integral of lighthill＇s acoustic analogy is used to extract the sound radiated from the cylinder. The profiles of mean velocity and turbulent fluctua- tions obtained are consistent with the previous experimental and computational results. The sound radiation at far field exhibits the characteristic of a dipole and directivity. The sound spectra display the -5/3 power law. It is shown that Vreman＇s SGS model in company with dynamic procedure is suitable for LES of turbulence generated noise.

关键词： Flows past circular cylinder Aerodynamicnoise Large-eddy simulation Unstructured grid Acousticanalogy

Size distribution of inclusions in 12%Cr stainless steel with a wide range of solidification cooling rates

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1157-1162页

作者： Han-song Yu Jian-guo li School of Materials Science and Engineering Shanghai Jiao Tong University

The effect of solidification cooling rate on the size and distribution of inclusions in 12%Cr stainless steel was investigated. A wide range of solidification cooling rates（from 0.05 to 106 K·s^-1） was achieved using various solidification processes, including conventional casting, laser remelting, and melt spinning. The size and distribution of inclusions in the steel were observed and statistically collected. For comparison, mathematical models were used to calculate the sizes of inclusions at different solidification cooling rates. Both the statistical size determined from observations and that predicted from calculations tended to decrease with increasing cooling rate; however, the experimental and calculated results did not agree well with each other at excessively high or low cooling rate. The reasons for this discrepancy were theoretically analyzed. For the size distribution of inclusions, the effect of cooling rate on the number densities of large-sized（〉 2 μm） inclusions and small-sized（≤ 2 μm） inclusions were distinct. The number density of inclusions larger than 1 μm was not affected when the cooing rate was less than or equal to 6 K·s^-1 because inclusion precipitation was suppressed by the increased cooling rate.

关键词： solidification cooling rate inclusions size distribution number density stainless steels