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Capturing Near-Equilibrium Solutions: A Comparison between High-Order Discontinuous Galerkin Methods and Well-Balanced Schemes

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Communications in Computational Physics 2019年第6期26卷 1-34页

作者： maria han veiga David A.Velasco-Romero Remi Abgrall Romain Teyssier Institute of Computational Science University of ZurichSwitzerland Institute of Mathematics University of ZurichSwitzerland Universidad Autonoma del Estado de Morelos Mexico Instituto de Ciencias Fisicas Universidad Nacional Aut́onoma de ḾexicoMexico

Equilibrium or stationary solutions usually proceed through the exact balance between hyperbolic transport terms and source terms. Such equilibrium solutions are affected by truncation errors that prevent any classical numerical scheme from capturing the evolution of small amplitude waves of physical significance. In order to overcome this problem, we compare two commonly adopted strategies: going to very high order and reduce drastically the truncation errors on the equilibrium solution, or design a specific scheme that preserves by construction the equilibrium exactly, the so-called well-balanced approach. We present a modern numerical implementation of these two strategies and compare them in details, using hydrostatic but also dynamical equilibrium solutions of several simple test cases. Finally, we apply our methodology to the simulation of a protoplanetary disc in centrifugal equilibrium around its star and model its interaction with an embedded planet, illustrating in a realistic application the strength of both methods.

关键词： Numerical methods benchmark well-balanced methods discontinuous Galerkin methods

The First Ground-based White Light Lunar Polarization Imaging:A New Kind of FeO Observation on the Near Side of the Moon

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Research in Astronomy and Astrophysics 2024年第6期24卷 1-6页

作者： Wei-Nan Wang Jin-Song Ping Ming-Yuan Wang Wen-Zhao Zhang han-Lin Ye Xing-Wei han Song-Feng Kou Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Astronomy Department Beijing Normal UniversityBeijing 100875China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Nanjing Institute of Astronomical Optics and Technology Chinese Academy of SciencesNanjing 210042China

Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes *** study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the *** obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the *** findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria *** the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the *** study may serve as a new diagnostic tool for the Moon.

关键词： techniques:photometric polarization methods:observational Moon

Die in pieces:How Drosophila sheds light on neurite degeneration and clearance

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Journal of Genetics and Genomics 2019年第4期46卷 187-199页

作者： maria L.Sapar Chun han Weill Institute for Cell and Molecular Biology Department of Molecular Biology and GeneticsCornell University

Dendrites and axons are delicate neuronal membrane extensions that undergo degeneration after physical injuries. In neurodegenerative diseases, they often degenerate prior to neuronal death. Understanding the mechanisms of neurite degeneration has been an intense focus of neurobiology research in the last two decades. As a result, many discoveries have been made in the molecular pathways that lead to neurite degeneration and the cell-cell interactions responsible for the subsequent clearance of neuronal debris. Drosophila melanogaster has served as a prime in vivo model system for identifying and characterizing the key molecular players in neurite degeneration, thanks to its genetic tractability and easy access to its nervous system. The knowledge learned in the fly provided targets and fuel for studies in other model systems that have further enhanced our understanding of neurodegeneration. In this review, we will introduce the experimental systems developed in Drosophila to investigate injuryinduced neurite degeneration, and then discuss the biological pathways that drive degeneration. We will also cover what is known about the mechanisms of how phagocytes recognize and clear degenerating neurites, and how recent findings in this area enhance our understanding of neurodegenerative disease pathology.

关键词： Drosophila Neurite degeneration Axon Dendrite Wallerian degeneration Phagocyte Phagocytosis PS exposure Injury assay

Homotypic Vacuole Fusion Requires VTI11 and Is Regulated by Phosphoinositides

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Molecular Plant 2014年第6期7卷 1026-1040页

作者： Sang Won han maria Fernanda Rodriguez-Welsh Marcela Rojas-Pierce Department of Plant and Microbial Biology North Carolina State University Raleigh NC 27695 USA

Most plant cells contain a large central vacuole that is essential to maintain cellular turgor. We report a new mutant allele of VTI11 that implicates the SNARE protein VTI11 in homotypic fusion of protein storage and lytic vacuoles. Fusion of the multiple vacuoles present in vtill mutants could be induced by treatment with Wortmannin and LY294002, which are inhibitors of Phosphatidylinositol 3-Kinase （PI3K）. We provide evidence that Phosphatidylinositol 3-Phosphate （Ptdlns（3）P） regulates vacuole fusion in vtill mutants, and that fusion of these vacuoles requires intact microtubules and actin filaments. Finally, we show that Wortmannin also induced the fusion of guard cell vacuoles in fava beans, where vacuoles are naturally fragmented after ABA-induced stomata closure. These results suggest a ubiquitous role of phosphoinositides in vacuole fusion, both during the development of the large central vacuole and during the dynamic vacuole remodeling that occurs as part of stomata movements.

关键词： vacuole SNARE phosphoinositides membrane fusion Wortmannin.

Green Attitudes, Human Values, and Wellbeing among Hospitality Service Employees

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International Journal of Mental Health Promotion 2022年第6期24卷 917-932页

作者： Faisal Mahmood maria Saleem Antonio Ariza-Montes Heesup han The University of Faisalabad Faisalabad38000Pakistan Social Matters Research Group Universidad Loyola AndalucíaCórdoba14004Spain College of Hospitality and Tourism Management Sejong UniversitySeoul05006Korea

This research aims to explore the intricate nature of the association between green attitudes and well-being in theworkplace. Based on the basic human value theory, this study attempted to unearth the moderating effects of itstwo main bipolar segments, namely self-transcendence-self-enhancement and openness to change-conservation.A quantitative approach with a sample of 1,532 hospitality employees from 35 European countries was used. Wefound that a green attitude contributes to deriving employee well-being. Further, we found empirical support forthe influence of human values, in the sense that this relationship is reinforced among the workers who are morealtruistic and receptive to changes. Moreover, this research suggests strategies oriented to reduce environmentaldegradation and achieve sustainable development in the hospitality sector. This article provides ideas to cope withthe challenges posed by COVID-19, particularly in the hospitality industry seriously damaged by the pandemicwhere the future of many jobs is in jeopardy.

关键词： Green attitude well-being human values hospitality employees hospitality sector environmental management

Diagnosis and characterization of the ribosomal DNA-ITS of potato rot nematode(Ditylenchus destructor) populations from Chinese medicinal herbs

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Journal of Integrative Agriculture 2023年第6期22卷 1763-1781页

作者： NI Chun-hui han Bian LIU Yong-gang maria MUNAWAR LIU Shi-ming LI Wen-hao SHI Ming-ming LI Hui-xia PENG De-liang College of Plant Protection Gansu Agricultural University/Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu ProvinceLanzhou 730070P.R.China Institute of Plant Protection Gansu Academy of Agricultural SciencesLanzhou 730070P.R.China Department of Biological Sciences University of LethbridgeLethbridge 4401Canada State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China

The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different hosts across China, including 37 populations from Chinese herbal medicine plants. Obtained sequences of ITS-rDNA and D2–D3of 28S-rDNA genes of D. destructor were compared and analyzed. Nine types of significant length variations in ITS sequences were observed among all populations. The differences in ITS1 length were mainly caused by the presence of repetitive elements with substantial base substitutions. Reconstructions of ITS1 secondary structures showed that the minisatellites formed a stem structure. Ten haplotypes were observed in all populations based on mutations and variations of helix H9. Among them, 3 known haplotypes(A–C) were found in 7 populations isolated from potato,sweet potato, and Codonopsis pilosula, and 7 unique haplotypes were found in other 36 populations collected from C. pilosula and Angelica sinensis compared with 7 haplotypes(A–G) according to Subbotin' system. These unique haplotypes were different from haplotypes A–G, and we named them as haplotypes H–N. The present results showed that a total of 14 haplotypes(A–N) of ITS-rDNA have been found in D. destructor. Phylogenetic analyses of ITSrDNA and D2–D3 showed that all populations of D. destructor were clustered into two major clades: one clade only containing haplotype A from sweet potato and the other containing haplotypes B–N from other plants. For further verification, PCR-ITS-RFLP profiles were conducted on 7 new haplotypes. Collectively, our study suggests that D. destructor populations on Chinese medicinal materials are very different from those on other hosts and this work provides a paradigm for relevant researches.

关键词： Ditylenchus destructor minisatellites ITS-RFLP phylogeny RNA secondary structure

Remote Sensing of Tropical Cyclone Thermal Structure from Satellite Microwave Sounding Instruments:Impacts of Optimal Channel Selection on Retrievals

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Journal of Meteorological Research 2018年第5期32卷 804-818页

作者： Yang han Fuzhong WENG Nanjing University of Information Science&Technology Nanjing 210044 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081

Accurate information on atmospheric temperature of tropical cyclones （TCs） is important for monitoring and pre- diction of their developments and evolution. For hurricanes, temperature anomaly in the upper troposphere can be de-rived from Advanced Microwave Sounding Unit （AMSU） and Advanced Technology Microwave Sounder （ATMS） through either regression-based or variational retrieval algorithms. This study investigates the dependency of TC warm core structure on emission and scattering processes in the forward operator used for radiance computations in temperature retrievals. In particular, the precipitation scattering at ATMS high-frequency channels can significantly change the retrieval outcomes. The simulation results in this study reveal that the brightness temperatures at 183 GHz could be depressed by 30-50 K under cloud ice water path of 1.5 mm, and thus, the temperature structure in hur-ricane atmosphere could be distorted if the ice cloud scattering was inaccurately characterized in the retrieval system. It is found that for Hurricanes Irma, maria, and Harvey that occurred in 2017, their warm core anomalies retrieved from ATMS temperature sounding channels 4 15 were more reasonable and realistic, compared with the retrievals from all other channel combinations and earlier hurricane simulation results.

关键词： Advanced Technology Microwave Sounder (ATMS) Microwave Retrieval Testbed (MRT) Warm core hurricane Irma maria Harvey

横向学术治理与纵向行政约束的博弈——俄罗斯大学治理模式变革案例分析

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中国高教研究 2016年第5期 73-76,80页

作者： Yaroslav Kuzminov maria Yudkevich 韩梦洁国立研究大学高级经济学院副校长俄罗斯莫斯科101000 大连理工大学高等教育研究院讲师辽宁大连116024

俄罗斯大学的治理模式在很大程度上是由大学与国家(政府)之间的关系类型决定的,同时也受大学内部运行的机构要素制约。俄罗斯的高等教育系统存在较强的纵向(行政)控制和较弱的横向(学术)控制。这种权力分配在很大程度上是由国家学术市... 详细信息

俄罗斯大学的治理模式在很大程度上是由大学与国家(政府)之间的关系类型决定的,同时也受大学内部运行的机构要素制约。俄罗斯的高等教育系统存在较强的纵向(行政)控制和较弱的横向(学术)控制。这种权力分配在很大程度上是由国家学术市场的衰弱和机构之间教职流动性低造成的。在过去十年里,传统以教席主导教学为核心的治理模式伴随着许多支持教职参与研究政策的出现而悄然发生改变。以国立研究大学经济学高级学院为例,该校近来实施了基于学术治理的新的控制和分配机制的变革,着力摆脱传统的低效率治理模式。

关键词：大学治理教师聘任学术文化世界一流大学

Construction of Synergistic Co and Cu Diatomic Sites for Enhanced Higher Alcohol Synthesis

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CCS Chemistry 2023年第4期5卷 851-864页

作者： Gaofeng Chen Olga A.Syzgantseva maria A.Syzgantseva Shuliang Yang Guihua Yan Li Peng Changyan Cao Wenxing Chen Zhiwei Wang Fengjuan Qin Tingzhou Lei Xianhai Zeng Lu Lin Weiguo Song Buxing han College of Energy Xiamen UniversityXiamen 361102 Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991 Fujian Engineering and Research Center of Clean and High-Valued Technologies for Biomass Xiamen Key Laboratory of Clean and High-Valued Utilization for BiomassXiamen 361102 College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005 Beijing National Laboratory for Molecular Science CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049 Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081 School of Environmental Engineering Henan University of TechnologyZhengzhou 450001 Institute of Urban and Rural Mining Changzhou UniversityChangzhou 213164

Higher alcohol synthesis(HAS)from syngas could efficiently alleviate the dependence on the traditional fossil ***,it is still challenging to construct high-performance HAS catalysts with satisfying selectivity,space–time yield(STY),and ***,we designed a diatomic catalyst by anchoring Co and Cu sites onto a hierarchical porous N-doped carbon matrix(Co/Cu–N–C).The Co/Cu–N–C is efficient for HAS and is among the best catalysts *** a COconversion of 81.7%,C2+OHselectivity could reach 58.5%with an outstanding C2+OH STY of 851.8 mg/g·*** found that the N4–Co1 and Cu1–N4 showed an excellent synergistic *** adsorption of CO occurred on the Co site,and the surrounding nitrogen sites served as a hydrogen reservoir for the CO reduction reactions to form ***,the Cu sites stabilized a CHOCu species to interact with CHxCo,facilitating a barrier-free formation of C2 species,which is responsible for the high selectivity of higher alcohols.

关键词： dual atomic catalyst synergistic effect heterogeneous catalysis carbonmaterial higher alcohol synthesis