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On visualization techniques comparison for large social networks overview:A user experiment

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Visual Informatics 2020年第4期4卷 23-34页

作者： Bruno Pinaud Jason Vallet guy Melancn University of Bordeaux CNRS UMR 5800 LaBRIFrance

Visualizing social networks,especially an overview emphasizing their structure,i.e.,communities and their interconnections,is known to be a challenging *** this paper,we present a set of design rationales to build such overview visualizations of social networks and our solution called *** evaluate its performances against two of the most wide-spread visualization techniques(matrix and node-link diagram)in a human–computer controlled experiment based on community-related *** none of the techniques emerge as the overwhelming winner,Jasper appears to be one of the best methods for each task;a fact sustained by the marks given by the ***,Jasper can be seen as an all-encompassing solution for quickly producing legible and compact overviews of large social networks on a single modern computer.

关键词： Overview visualization User evaluation Graphs andnetworks Social networks

A Multigrid Method for a Model of the Implicit Immersed Boundary Equations

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Communications in Computational Physics 2012年第7期12卷 378-400页

作者： Robert D.guy Bobby Philip Department of Mathematics University of California DavisDavisCA 95616USA Oak Ridge National Laboratory Oak RidgeTN 37831USA

Explicit time stepping schemes for the immersed boundary method require very small time steps in order to maintain *** the equations that arise from an implicit discretization is ***,several different approaches have been proposed,but a complete understanding of this problem is still emerging.A multigrid method is developed and explored for solving the equations in an implicittime discretization of a model of the immersed boundary *** model problem consists of a scalar Poisson equation with conformation-dependent singular forces on an immersed *** model does not include the inertial terms or the incompressibility *** method is more efficient than an explicit method,but the efficiency gain is *** multigrid method alone may not be an effective solver,but when used as a preconditioner for Krylov methods,the speed-up over the explicit-time method is *** example,depending on the constitutive law for the boundary force,with a time step 100 times larger than the explicit method,the implicit method is about 15-100 times more efficient than the explicit method.A very attractive feature of this method is that the efficiency of the multigrid preconditioned Krylov solver is shown to be independent of the number of immersed boundary points.

关键词： Preconditioning implicit methods fluid-structure interaction

Genome editing in Bombyx mori: New opportunities for silkworm functional genomics and the sericulture industry

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Insect Science 2019年第6期26卷 964-972页

作者： San-Yuan Ma guy Smagghe Qing-You Xia State Key Laboratory of Silkworm Genome Biology Southwest University ChongqingChina Chongqing Engineering and Technology Research Center for Novel Silk Materials Southwest University Chongqing China Department of Crop Protection Faculty of Bioscience Engineering Ghent University Ghent Belgium

In recent years, research in life sciences has been remarkably revolutionized owing to the establishment, development and application of genome editing technologies. Genome editing has not only accelerated fundamental research but has also shown promising applications in agricultural breeding and therapy. In particular, the clustered, regularly interspaced, short palindromic repeat (CRISPR) technology has become an indispensable tool in molecular biology owing to its high efficacy and simplicity. Genome editing tools have also been established in silkworm (Bombyx mori), a model organism of Lepidoptera insects with high economic importance. This has remarkably improved the level and scope of silkworm research and could reveal new mechanisms or targets in basic entomology and pest management studies. In this review, we summarize the progress and potential of genome editing in silkworm and its applications in functional genomic studies for generating novel genetic materials.

关键词： CRISPR genome editing silkworm TALEN ZFN

Comparing growth and fine root distribution in monocultures and mixed plantations of hybrid poplar and spruce

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Journal of Forestry Research 2013年第2期24卷 247-254页

作者： Lahcen Benomar Annie DesRochers guy R. Larocque Chaire industrielle CRSNG-UQAT-UQAM en aménagement forestier durable. Université du Québec en Abitibi-Témiscamingue Natural Resources Canada Laurentian Forestry Centre

Disease prevention, biodiversity, productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations. The objective of this study was to evaluate early growth and productivity of two hybrid poplar clones, P. balsamifera x trichocarpa （PBT） and P. maximowiczii x balsamifera （PMB）, one improved family of Norway spruce （Picea glauca （PA）） and one improved family of white spruce （Picea abies （PG）） growing under different spacings in monocultures and mixed plots. The plantations were established in 2003 in Abitibi-Témiscamingue, Quebec, Canada, in a split plot design with spacing as the whole plot factor （1 × 1 m, 3 × 3 m and 5 × 5 m） and mixture treatments as subplot factor （pure： PBT, PMB, PA and PG, and 1：1 mixture PBT：PA, PBT：PG, PMB：PA and PMB：PG）. Results showed a beneficial effect of the hybrid poplar-spruce mixture on diameter growth for hybrid poplar clones, but not for the 5 × 5 m spacing because of the relatively young age of the plantations. Diameter growth of the spruces decreased in mixed plantings in the 1 × 1 m, while their height growth increased, resulting in similar aboveground biomass per tree across treatments. Because of the large size differences between spruces and poplars, aboveground biomass in the mixed plantings was generally less than that in pure poplar plots. Leaf nitrogen concentration for the two spruce families and hybrid poplar clone PMB was greater in mixed plots than in monocultures, while leaf nitrogen concentration of clone PBT was similar among mixture treatments. Because of its faster growth rate and greater soil resources demands, clone PMB was the only one showing an increase in leaf N with increased spacing between trees. Fine roots density was greater for both hybrid poplars than spruces. The vertical distribution of fine roots was insensitive to mixture treatment.

关键词： Picea glauca Populus balsamifera × trichocarpa P. maximowiczii × balsamifera mixed-species monoculture spacing fine root

Myosuppressin influences fecundity in the Colorado potato beetle,Leptinotarsa decemlineata

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Insect Science 2021年第4期28卷 1191-1201页

作者： Shun-Hua Gui Clauvis Nji Tizi Taning guy Smagghe Laboratory of Agrozoology Department of Plants and CorpsGhent UniversityGhentBelgium

Insect neuropeptides regulate various physiological processes,such as reproduction,feeding,growth and development,and have been considered as viable targets in the development of alternative strategies for pest *** these neuropeptides is myosuppressin(MS),a very conserved neuropeptide that has been reported to regulate cardiac and skeletal muscle contractility,feeding and pupal diapause in *** this study,we investigated the involvement of MS in fecundity in a notorious defoliator of potato and other solanaceous plants,the Colorado potato beetle(CPB),Leptinotarsa *** identified an MS-precursor-encoding transcript in the *** transcriptomic database and then evaluated its transcript levels in various CPB *** transcript levels were found to be highest in the central nervous system,gut and muscle of CPB males and *** investigate the role of MS in fecundity,MS was silenced in adult CPBs through RNA interference(RNAi).This resulted in a significant reduction in oviposition(over 80%)and oocyte size(69%)in the treated beetles compared to the ***,the reduction in oviposition in treated females was confirmed to be dependent on MS knockdown and independent of male ***,MS-knockdown in females resulted in decreased levels of ecdysteroid hormone titers and the transcript levels of its ***,the injection of 20-hydroxyecdysone into females following MS knockdown could rescue ovary ***,this study highlights the important role played by MS in regulating fecundity in CPB.

关键词： ecdysteroid fecundity Leptinotarsa decemlineata myosuppressin neuropeptide

AN EXPERIMENTAL STUDY ON THE SOL/GEL PHASE TRANSITION OF LINEAR POLYMER IN THE PRESENCE OF CROSSLINKERS

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Chinese Journal of Polymer Science 1996年第1期14卷 63-70页

作者：韩明施良和叶美玲 MULLER guy Polymer Physics Laboratory Institute of Chemistry Academia Sinica Beijing 100080 Polymeres Biopolymeres Membranes URA 500 du CNRS Faculte des Sciences Universite de Rouen 76134 Mont Saint-Aignan France

The sol/gel phase diagrams were studied for two systems: polyacrylamide/Cr (III) and polyacrylamide/glyoxal. Sol or gel phase could be distinguished according to the concentrations of polymer and crosslinker. The boundary polymer concentration did not depend on the types of gelation and decreased with increasing polymer dimension (molecular weight and conformation). The gelation, which is basically interchain bonding, requires the occurrence of entanglement. The overlap concentration is thus considered as the minimum polymer concentration required for gelation.

关键词： polyacrylamide gel sol/gel phase diagram overlap concentration Cr (III) glyoxal

Characterisation of likelihood of gas hydrates occurrence in the South China Sea based on Bonferroni mean-based TOPSIS and fuzzy set theory

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Geoscience Frontiers 2023年第2期14卷 59-70页

作者： Pierre guy Atangana Njock Shui-Long Shen Annan Zhou MOE Key Laboratory of Intelligent Manufacturing Technology Department of Civil and Environmental EngineeringCollege of EngineeringShantou UniversityGuangdong 515063China Discipline of Civil and Infrastructure Engineering School of EngineeringRoyal Melbourne Institute of TechnologyVictoria 3001Australia

The efficiency of gas hydrate production depends on the success of gas exploration and occurrence *** existing evaluation models are generally univariate and only applicable to certain geological *** study presents a holistic approach to evaluate the likelihood of gas hydrate occurrence by supplying an index for mapping gas hydrate levels with *** approach integrates a generalised TOPSIS method with the fuzzy set *** expedition of gas hydrate conducted in the Shenhu area of the South China Sea was adopted as a case study to assess the reliability of the proposed *** a multivariate model,the proposed approach enables the capture of non-linearity associated with gas hydrates in its *** magnitude of the strength of the influential factor varies substantially from one site to another across the Shenhu *** results also show that no site achieves the highest likelihood‘Level V’.These results are consistent with the gas saturation values obtained using Archie’s *** example,at SH4 and SH7,the values of the likelihood index are the highest between 170–185 m and 150–165 m,respectively,and the observed saturation at these locations varies from 20%(SH4)to 43%(SH7).The proposed likelihood index yields a prominent ability to quantify the level of occurrence of gas hydrates with depth at different *** appears to be an efficient multicriteria system bound to improve the management of the gas production trial stage.

关键词： Gas hydrates South China Sea Geologic controls Occurrence characterization Energy resource

GEOLOGICAL DATING PRINCIPLES QUESTIONED Paleohydraulics:a new approach

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大地测量与地球动力学 2003年第B12期23卷 119-126页

作者： guy Berthault 28 boulevard Thiers

Stratigraphy, the basis of geological dating was founded in the ⅩⅦ century on the three well known principles assumed by Stenon: superposition, continuity, original horizontality. These three principles came from a postulate in sedimentology: layers of sub soil are strata of ancient successive sediments. Stratigraphy is, therefore,based upon data acquired from *** the basis of successive observations and experiments this paper realises and verifies that Stenon’s stratigraphic model was not in line with experimental data because it had “overlooked” the major variable factor of sedimentology: the current and its chronological effects. The sedimentological process can, effectively, be divided into three phases: erosion, transport and deposit of sediments,with the liquid current being the vector of transport. Stenon’s stratigraphy only took into account the third phase of sedimentology, the deposit, implicitly assuming the velocity of current to be nil. The author of this paper simulated the constitution of layers of sediment generated at variable velocities from differing *** reincorporated the chronology of currents into the field of his scientific investigations, as it was indispensable for modelling all the interlinked sequences in sedimentology, stratigraphy and geological *** author introduced paleohydraulics as the new approach to geological dating to integrate the two ends of the chain,and refers to radiometric dating measures of eruptive rocks recognised as aberrant in relation to the date of *** speaking,the new approach paleohydraulics brings about the establishment of experimental sedimentology and Stenon’s ⅩⅦ century postulate and principles are no more than interpretations that must be carefully checked with data from observation and the laboratory.

关键词：地质时期古水利学地层学沉积学实验室研究主要阶段研究原则

Spatial and Temporal Variability of Farm Size in China in Context of Rapid Urbanization

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Chinese Geographical Science 2013年第5期23卷 607-619页

作者： TAN Minghong guy M ROBINSON LI Xiubin XIN Liangjie Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Centre for Rural Health&Community Development University of South Australia

During the last 30 years, China has witnessed rapid economic growth and dramatic urbanization, with about 1.2 x 107 rural people migrating annually into urban areas. Meanwhile, especially since 1995, the rural population has been declining, which is closely linked to land circulation and the increase in farm size in many villages. Increasing scale of farming operations is often regarded as a key to avoiding the abandonment of farmland and to increasing the income of rural farmers. However, until now, there has been little research on the spatial and temporal variability of farm size at the national level in China. Using data from the national agricultural cen- sus and rural household surveys, this study examines the characteristics of land use circulation and the consequent changes in the area of farmland per household. The results show that： 1） 12.2% of rural households were involved in land circulation at the national level. The highest amounts of land circulation have occurred in those provinces where the farmland per capita is more than 0.2 ha or less than 0.1 ha; 2） over 80% of households operate less than 0.6 ha of farmland; 3） the proportion of mid-sized farms （between 0.2 ha and 0.6 ha per household） has decreased while the smallest and the largest farms have increased. This bears some similarity with the phenomenon known as the ＇disappearing middle＇, referring to the changes in farm size. This study establishes a framework for interpreting the factors affecting the changes in farm size in China, which include two promoting factors （urbanization and agriculture） and four hindering fac- tors （agricultual land system, household registration, stable clan system, and farmland loss）.

关键词： farm size land circulation urbanization China