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Migratory flight of insect pests within a year-round distribution: European corn borer as.a.case study

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Journal of Integrative Agriculture 2018年第7期17卷 1485-1505页

作者： thomas W.sappington Corn Insects.a.d Crop Genetics Res.a.ch Unit Agricultural Research ServiceUSDA

Insect migratory flight differs fundamentally from most other kinds of flight behavior, in that it is non-appetitive. The adult is not s.a.ching for anything, and migratory flight is not terminated by encounters with potential resources. Many insect pests of agricultural crops.a.e long-dis.a.ce migrants, moving from lower latitudes where they overwinter to higher latitudes in the spring to exploit superabundant, but s.a.onally ephemeral, host crops. The migratory nature of these pests is somewhat easy to recognize because of their sudden appearance in areas where they had been absent only a day or two earlier. Many other serious pests survive hostile winter conditions by diapausing, and therefore do not require migration to move between overwintering and breeding ranges. Yet there is evidence of migratory behavior engaged in by several pest species that inhabit high latitudes year-round. In these cases, the consequences of migratory flight are not immediately noticeable at the population level, because migration takes place for the most part within their larger year-round distribution. Nevertheless, the potential population-level consequences can be quite important in the contexts of pest management and insect resis.a.ce management. As.a.case study, I review the evidence for migratory flight behavior by individual European corn borer adults, and discuss the importance of unders.a.ding it. The kind of migratory behavior posited for pest species inhabiting a permanent distribution may be more common than we realize.

关键词： migration dispersal flight movement ecology European corn borer Ostrinia nubilalis

Non-leaving-face property for marked surfaces

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Frontiers of Mathematics in China 2019年第3期14卷 521-534页

作者： thomas BRUsTLE Jie ZHANG Departement de Mathematiques Universite de Sherbrooke Sherbrooke J1K 2R1 Canada school of Mathematics.a.d s.a.istics Beijing Institute of Technology Beijing 100081 China

Abstract We consider the polytope arising from a marked surface by flips of triangulations. D. D. sleator, R. E. Tarjan, and W. P. Thurston [J. Amer. Math. soc., 1988, 1(3): 647 681] studied the diameter of the associahedron, which is the polytope arising from a marked disc by flips of triangulations. They showed that every shortest path between two vertices in a face does not leave that face. We give a new method, which is different from the one used by V. Disarlo and H. Parlier [arXiv: 1411.4285] to es.a.lish the same non-leaving-face property for all unpunctured marked surfaces.

关键词： Marked surface non-leaving-face property exchange graph

JAMEs GLIMM:MATHEMATICIAN,FRIEND,MENTOR

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Acta Mathematica scientia 2010年第2期30卷 369-376页

作者： Arthur Jaffe thomas spencer Department of Mathematics Harvard University school of Mathematics Institute for Advanced Study

A description of Jim＇s contributions to mathematics would take us far beyond our expertise. Jim was never content to spend too long in any one area of mathematics. Operator algebras, hyperbolic systems of conservation laws, fluid dynamics, quantum field theory and s.a.istical mechanics.a.d the computational aspects of applied mathematics.a.e just a few of the areas to which Jim has contributed. Here we relate a few impressionistic recollections of personal interactions, together with some ideas.a.out his work in quantum field theory and s.a.istical mechanics. In spite of the non-technical character of these observations, we hope nevertheless that they will provide pleasure for our dear friend and for other readers.a. well.

关键词： JAMEs GLIMM work

A two-density approach to the general many-body problem and a proof of principle for s.a.l atoms.a.d molecules

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Frontiers of physics 2019年第2期14卷 89-96页

作者： thomas Pope Werner Hofer school of Natural and Environmental sciences Newcastle UniversityNewcastle NE1 7RUUnited Kingdom Institute of Physics & University of Chinese Academy of sciences Chinese Academy of SciencesBeijing 100190China

An extended electron model fully recovers many of the experimental results of quantum mechanics while it avoids many of the pitfalls.a.d remains generally free of paradoxes. The formulation of the manybody electronic problem here resembles the Kohn s.a. formulation of s.a.dard density functional theory. However, rather than referring electronic properties to a large set of single electron orbitals, the extended electron model uses only mass density and field components, leading to a subs.a.tial increase in computational efficiency. To date, the Hohenberg-Kohn theorems have not been proved for a model of this type, nor has.a.universal energy functional been presented. In this paper, we address these problems.a.d show that the Hohenberg Kohn theorems do also hold for a density model of this type. We then present a proof^of^concept practical implementation of this method and show that it reproduces the accuracy of more widely used methods on a test-set of s.a.l atomic systems, thus paving the way for the development of fast, efficient and accurate codes on this basis.

关键词： many-body condensed matter Hartree-Fock density functional theory extended electrons

A GIs tool for infinite slope s.a.ility analysis(GIs-TIs.a.

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Geoscience Frontiers 2021年第2期12卷 756-768页

作者： Rüdiger Escobar-Wolf Jonathon D.sanders C.L.Vishnu thomas Oommen K.s.sajinkumar Department of Geological and Mining Engineering and sciences Michigan Technological UniversityHoughtonMIUSA Department of Geology University of KeralaThiruvananthapuram 695581KeralaIndia

Landslides.a.e one of the most common and a destructive natural hazard in mountainous terrain and thus evaluating their potential locations.a.d the conditions under which they may occur is crucial for their hazard *** landslide occurrence in soil and regolith covered slopes.a.e often modeled using the infinite slope model,which characterizes the slope s.a.ility in terms of a factor of safety(Fs) *** approaches have been followed to also assess.a.d propagate uncertainty through such ***(2004) introduced the use of the First Order second Moment(FOsM) method to propagate input uncertainty through the infinite slope model,further developing the model and implementing it in the PIsA-m software package(Haneberg,2007).Here we present an ArcPy implementation of PIsA-m algorithms,which can be run from EsRI ArcMap in an entirely consistent georeferenced framework,and which we call "GIs Tool for Infinite slope s.a.ility Analysis"(GIs-TIs.a..Users can select between different input options,e.g.,following a similar input style as for PIsA-m,i.e., using an *** parameters input file,or providing each input parameter as.a.raster or cons.a.t value,through the program graphic user *** outputs can include Fs mean and s.a.dard deviation estimates,the probability of failure(Fs same seismic analysis.a.proach as in PIsA-m, the Newmark acceleration can also be done,for which raster files of the mean,s.a.dard deviation,probability of exceedance,and RI are also *** of the code is done by replicating the results obtained with the PIsA-m code for different input options,within a 10-5 relative *** Carlo modeling is.a.so applied to validate GIs-TIs.a.outputs,showing a good overall correspondence.A case study was performed for Kannur district,Kerala,India,where an extensive landslide databa se for the year 2018 was.a.ailable.81.19% of the actual

关键词： Landslides GIs-TIssA PIsA-m FOsM Factor of safety

MIXED INTERIOR PENALTY DIsCONTINUOUs GALERKIN METHODs FOR ONE-DIMENsIONAL FULLY NONLINEAR sECOND ORDER ELLIPTIC AND PARABOLIC EQUATIONs

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Journal of Computational Mathematics 2014年第2期32卷 107-135页

作者： Xiaobing Feng thomas Lewis Department of Mathematics The University of Tennessee Knoxville TN 37996 U.S.A. Department of Mathematics.a.d s.a.istics The University of North Carolina at Greensboro NC 27402 U.S.A.

This paper is concerned with developing accurate and efficient numerical methods for one-dimensional fully nonlinear second order elliptic and parabolic partial differential equations （PDEs）. In the paper we present a general framework for constructing high order interior penalty discontinuous Galerkin （IP-DG） methods for approximating viscosity solutions of these fully nonlinear PDEs. In order to capture discontinuities of the second order derivative uxx of the solution u, three independent functions p1,p2 and p3 are introduced to represent numerical derivatives using various one-sided limits. The proposed DG frame- work, which is based on a nons.a.dard mixed formulation of the underlying PDE, embeds.a.nonlinear problem into a mostly linear system of equations where the nonlinearity has been modified to include multiple values of the second order derivative uxz. The proposed framework extends.a.companion finite difference framework developed by the authors in [9] and allows for the approximation of fully nonlinear PDEs using high order polynomials.a.d non-uniform meshes. In addition to the nons.a.dard mixed formulation setting, another main idea is to replace the fully nonlinear differential operator by a numerical operator which is consistent with the differential operator and satisfies certain monotonicity （called g-monotonicity） properties. To ensure such a g-monotonicity, the crux of the construction is to introduce the numerical moment, which plays.a.critical role in the proposed DG frame- work. The g-monotonicity gives the DG methods the ability to select the mathematically ＂correct＂ solution （i.e., the viscosity solution） among all possible solutions. Moreover, the g-monotonicity allows for the possible development of more efficient nonlinear solvers.a. the special nonlinearity of the algebraic systems can be explored to decouple the equations. This paper also presents.a.d analyzes numerical results for several numerical test problems which are used to guage

关键词： Fully nonlinear PDEs Viscosity solutions Discontinuous Galerkin methods.

Rationally connected varieties -On a conjecture of Mumford

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science China Mathematics 2017年第6期60卷 1019-1028页

作者： LAZIC Vladimir PETERNELL thomas Mathematisches Institut Universitat Bonn Bonn 53115 Germany Mathematisches Institut Universitat Bayreuth Bayreuth 95440 Germany

We es.a.lish a conjecture of Mumford characterizing rationally connected complex projective manifolds in several cases.

关键词： rationally connected varieties Mumford conjecture non vanishing conjecture abundance

THERE Is NO MATHEMATICAL VALIDITY FOR UsING FUZZY NUMBER CRUNCHING IN THE ANALYTIC HIERARCHY PROCEss

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Journal of systems science and systems Engineering 2006年第4期15卷 457-464页

作者： thomas L. s.a.Y University of Pittsburgh Pittsburgh PA 15260

Fuzzy logic has difficulty producing valid answers in decision-making. Absent are theorems to prove that it works to produce results.a.ready known that are being estimated with judgments by transforming such judgments numerically. The numerical representation of judgments in the AHP is.a.ready fuzzy. Making fuzzy judgments more fuzzy does not lead to a better more valid outcome and it often leads to a worse one. The compatibility index of the AHP is used to illustrate how the answers obtained by fuzzifying AHP judgments do not produce better results than direct derivation of the principal eigenvector. Other authors who did experiments with given data in decision making quoted in the conclusions section of the paper, have observed that fuzzy sets gives the poorest answers.a.ong all methods used to derive best decisions.

关键词： Analytic Hierarchy Process fuzzy logic compatibility index validity

Hydrothermal carbonization of livestock mortality for the reduction of pathogens.a.d microbially-derived DNA

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Frontiers of Environmental science & Engineering 2017年第3期11卷 107-114页

作者： thomas F. Ducey Jessica C. Collins Kyoung s. Ro Bryan L. Woodbury D. Dee Griffin Coas.a. Plains soil Water and Plant Research Center Agricultural Research Service United States Department of Agriculture Florence SC 29501 USA south Carolina Governor's school for science and Mathematics Hartsville SC 29550 USA U.s. Meat Animal Res.a.ch Center Agricultural Research Service United States Department of Agriculture Clay Center NE 68933 USA University of Nebras.a.Lincoln Great Plains Veterinary Education Center Lincoln NE 68588 USA

Hydrothermal carbonization （HTC）, utilizing high temperature and pressure, has the potential to treat agricultural waste via inactivating pathogens, antibiotic resis.a.ce genes （ARG）, and contaminants of emerging concern （CEC） in a environmental and economical manner. Livestock mortality is one facet of agricultural waste that can pose a threat to the surrounding environment. While several methods.a.e utilized to treat livestock mortality, there remains.a.paucity of data on the elimination of microbially- derived DNA in these treatment practices. This DNA, most notably ARGs, if it survives treatment can be reintroduced in agricultural environments where it could potentially be passed to pathogens, posing a risk to animal and human populations. HTC treatments have been successfully utilized for the treatment of CECs, however very little is understood on how ARGs survive HTC treatment. This study aims to fill this knowledge gap by examining the survivability ofmicrobially-derived DNA in the HTC treatment of livestock mortality. We examined three treatment temperatures （100℃, 150℃, and 200℃） at autogenic pressures.a. three treatment times （30, 60, and 240 min）. We examined the amplification of a plasmid-bome reporter gene carried by Escherichia coli DH 10B introduced to both beef bone and tissue. Results indicate that while all three temperatures, at all treatment times, were suitable for complete pathogen kill, only temperatures of 150℃ and 200℃ were sufficient for eliminating microbial DNA. These results serve as the basis for future potential HTC treatment recommendations for livestock mortality when considering the elimination of pathogens.a.d ARGs.

关键词： High-temperature carbonization Microbial DNA Livestock mortality