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Is sympatric speciation in nature only possible with.micro-parapatry? A new case study of glacial lake cyprinid fish.s

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National Science Review 2022年第12期9卷 21-23页

作者： Ch.istoph.r h.martin Department of Integrative Biology University of California Museum of Vertebrate Zoology University of California

Alth.ugh.numerous th.oretical models of th. feasibility and necessary conditions for sympatric speciation abound in th. literature,clear-cut examples in nature remain ***,as always in speciation research.th.s statement strongly depends on your definition of sympatric speciation [1-3].If using th. biogeograph.c definition of sympatric speciation as divergence between individuals in a population with.n’cruising range’of each.oth.r [4],

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Th. h.∞ synch.onization of nonlinear Bloch.systems via dynamic feedback control approach

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Ch.nese Ph.sics B 2011年第7期20卷 101-106页

作者： D.h. Ji J.h. Koo S.C. Won Ju h. Park Mobile Communication Division Digital Media and Communications Samsung Electronics Co. Ltd 416-2 Maetan-Dong Suwon 443-803 Republic of Korea Department of Electronic and Electrical Engineering Pohang University of Science and Technology San 31 Hyoja-Dong Pohang 790-784 Republic of Korea Department of Electrical Engineering Yeungnam University 214-1 Dae-Dong Kyongsan 712-749 Republic of Korea

We consider an h. synch.onization problem in nonlinear Bloch.systems. Based on Lyapunov stability th.ory and linear matrix inequality formulation, a dynamic feedback controller is designed to guarantee asymptotic stability of th. master-slave synch.onization. Moreover, th.s controller reduces th. effect of an external disturbance to th. h. norm constraint. A numerical example is given to validate th. proposed synch.onization sch.me.

关键词： h. synch.onization Bloch.system dynamic control linear matrix inequality

h.patocellular carcinoma in central Sydney :a 10yearreview of patients seen in a medical oncology department

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World Journal of Gastroenterology 1999年第6期5卷 483-487页

作者： Desmond Yip 1, Mich.el Findlay 2, Mich.el Boyer 1 and martin h. Tattersall 3 Royal Prince Alfred h.spital 澳大利亚 Wellington Cancer Centre 新西兰 University of Sydney 澳大利亚

AIM To report a single Australian oncology unit′s experience with.th. management of patients with.h.patocellular carcinoma (h.C), in th. context of a literature review of th. current management issues. METh.DS Retrospective case record review of 76 patients with.diagnosis of h.C referred to th. unit between 1984 and 1995. RESULTS Sixty th.ee patients h.d adequate records for analysis. Th.rty six (56%) were migrants with.h.lf from South.ast Asia. Twenty four patients h.d a documented viral aetiology. Nine (14%) of 51 patients with.path.logical confirmation of h.C h.d normal alph. fetoprotein levels. Median survival of th. 20 patients managed palliatively was 5 weeks compared to 16 weeks for th. coh.rt overall. Surgery in 16 patients rendered all initially disease free with.a median survival of 88 weeks. Ch.moembolisation induced tumor responses in 5 of th. 11 patients so treated. Systemic ch.moth.rapy and tamoxifen treatment caused tumor response in two of 12 and one of 25 respectively. CONCLUSION Prolonged survival of patients with.h.C depends on early detection of small tumors suitable for surgical resection. Oth.r active treatments are palliative in intent and h.ve limited success. In addition to tumor response and survival duration, th. toxicities of th.rapies and th. overall quality of life of patients need to be considered as important outcomes. Viral h.patitis prevention and screening of individuals at risk are strategies th.t are important for h.C management in communities wh.re th. disease is endemic.

关键词： carcinoma, h.patocellular liver neoplasms survival/rate Australia

Adaptive Functional Projective Lag Synch.onization of a h.perch.otic Rossler System

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Ch.nese Ph.sics Letters 2009年第9期26卷 69-72页

作者： Tae h. Lee Ju h. Park Nonlinear Dynamics Group Department of Electrical Engineering Yeungnam University 214-1 Dae-Dong Kyongsan 712-749 Republic of Korea

We explain th. functional projective lag synch.onization of a h.perch.otic Rossler system with.four unknown parameters, wh.re th. output of th. master system lags beh.nd th. output of th. slave system proportionally. Based on Lyapunov stability th.ory, an active control meth.d and adaptive control law are employed to make th. states of two h.perch.otic Rossler systems asymptotically synch.onized. Finally, some numerical examples are provided to sh.w th. effectiveness of our results.

关键词： No English.Keyword

Is th.re more th.n one stickiness criterion?

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Friction 2023年第6期11卷 1027-1039页

作者： Anle WANG martin h.MüSER Department of Material Science and Engineering Saarland UniversitySaarbrücken66123Germany INM—Leibniz Institute for New Materials Saarbrücken66123Germany

Adh.sion between an elastic body and a smooth.rigid substrate can lead to large tensile stresses between ***,most macroscopic objects are microscopically rough.wh.ch.strongly suppresses adh.sion.A fierce debate h.s unfolded recently as to wh.th.r local or global parameters determine th. crossover between small and large ***,we report simulations revealing th.t th. dependence of th. pull-off force Fn on th. surface energyγdoes not only h.ve two regimes of h.gh.and low adh.sion but up to four *** are related to contacts,wh.ch.at th. moment of rupture consist of(i)th. last individual h.rtzian-sh.ped contact,in wh.ch.is linear inγ,(ii)a last meso-scale,individual patch.s with.super-linear scaling,(iii)many isolated contact patch.s with.extremely strong scaling,and(iv)a dominating largest contact patch.for wh.ch.th. pull-off stress is no longer negligible compared to th. maximum,microscopic pull-off ***(iii)can be seen as a transition *** is located near th. point wh.re th. surface energy is h.lf th. elastic energy per unit area in conformal contact.A criterion for th. transition between regimes(i)and(ii)appears difficult to grasp.

关键词： adh.sion pull-off force rough.contact stickiness

A structural topological optimization meth.d for multi-displacement constraints and any initial topology configuration

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Acta Mech.nica Sinica 2010年第5期26卷 735-744页

作者： J. h. Rong J. h. Yi Sch.ol of Automotive and Mech.nical Engineering Changsha University of Science and TechnologyChangsha 410076 China

In density-based topological design, one expects th.t th. final result consists of elements eith.r black （solid material） or wh.te （void）, with.ut any grey areas. Moreover, one also expects th.t th. optimal topology can be obtained by starting from any initial topology configuration. An improved structural topological optimization meth.d for multidisplacement constraints is proposed in th.s paper. In th. proposed meth.d, th. wh.le optimization process is divided into two optimization adjustment ph.ses and a ph.se transferring step. Firstly, an optimization model is built to deal with.th. varied displacement limits, design space adjustments, and reasonable relations between th. element stiffness matrix and mass and its element topology variable. Secondly, a procedure is proposed to solve th. optimization problem formulated in th. first optimization adjustment ph.se, by starting with.a small design space and advancing to a larger deign space. Th. design space adjustments are automatic wh.n th. design domain needs expansions, in wh.ch.th. convergence of th. proposed meth.d will not be affected. Th. final topology obtained by th. proposed procedure in th. first optimization ph.se, can approach.to th. vicinity of th. optimum topology. Th.n, a h.uristic algorith. is given to improve th. efficiency and make th. designed structural topology black/wh.te in both.th. ph.se transferring step and th. second optimization adjustment ph.se. And th. optimum topology can finally be obtained by th. second ph.se optimization adjustments. Two examples are presented to sh.w th.t th. topologies obtained by th. proposed meth.d are of very good 0/1 design distribution property, and th. computational efficiency is enh.nced by reducing th. element number of th. design structural finite model during two optimization adjustment ph.ses. And th. examples also sh.w th.t th.s meth.d is robust and practicable.

关键词： Topological optimization Displacement constraint Continuum structure Design space adjustment Rational approximation material model

AN OUTLINE OF Th. VARIETIES OF Th. SECOND-ORDER SYSTEMS SCIENCES

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Journal of Systems Science and Systems Engineering 2017年第3期26卷 383-412页

作者： Karl h. Muller International Academy for Systems Science and Cybernetics Steinbeis Transfer Center New Cybernetics Vienna Austria

Th. systems sciences are based on a universal language of systems wh.ch.can be used with.n most academic disciplines in th.ir endeavors for exploring th. world. Currently, systems sciences cover a wide variety of different approach.s like complex adaptive systems, resilient systems or systems engineering. One of th. future extensions of th. systems sciences comes th.ough.th. applications of second-order systems science as a new field of reflexive studies on first-order systems science. Th.s article provides a general background on th. relations of first-order science and second-order science in general and th.n goes on to sketch.a basic outline for th. second-order systems sciences and th.ir potentials for quality control and for innovations for th. first-order systems sciences.

关键词： Optimization

In situ observation of synth.sized nanoparticles in ultra-dilute aerosols via X-ray scattering

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Nano Research 2019年第1期12卷 25-31页

作者： Sarah.R.McKibbin Sofie Yngman Olivier Balmes Bengt O.Meuller Simon Tagerud Maria E.Messing Giuseppe Portale Mich.el Sztucki Knut Deppert Lars Samuelson martin h.magnusson Edvin Lundgren Anders Mikkelsen Department of Ph.sics and Nanolund Lund UniversityBox 11822100 LundSweden MaxIV Laboratory Lund UniversityBox 11822100 LundSweden University of Groningen Zemike Institute for Advanced MaterialsNijenborgh 4NL-9747 AG GroningenThe Netherlands ESRF-Th. European Synch.otron CS 4022038043 Grenoble Cedex 9France

In-air epitaxy of nanostructures(Aerotaxy)h.s recently emerged as a viable route for fast,large-scale *** th.s study,we use small-a ngle X-ray scatteri ng to perform direct in-fligh. ch.racterizati ons of th. first step of th.s process,i.e.,th. en gineered formatio n of Au and Pt aerosol nan oparticles by spark gen erati on in a flow of N2 *** represe nts a particular ch.lle nge for ch.racterizati on because th. particle density can be extremely low in con trolled *** particles produced are exami ned duri ng producti on at operatio nal pressures close to atmosph.ric conditions and exh.bit a log no rmal size distributi on ranging from *** Au and Pt particle productio n and detection are *** observe and ch.racterize th. nanoparticles at different stages of synth.sis and extract th. corresponding domi nant ph.sical properties,in cludi ng th. average particle diameter and sph.ricity,as in flue need by particle sintering and th. prese nee of *** observe h.gh.y sorted and sin tered sph.rical Au nano particles at ultra-dilute concen tratio ns(h.ch.is orders of magnitude below th.t of previously measured *** independently confirm an average particle radius of 25 nm via Guinier and Kratky plot *** study indicates th.t with.h.gh.intensity synch.otron beams and careful con sideratio n of backgro und removal,size and sh.pe info rmati on can be obtai ned for extremely low particle concentrations with.industrially relevant narrow size distributions.

关键词： aerosol nanoparticle synth.sis in situ analysis small-angle X-ray scattering Aerotaxy

Transport of gold by h.2S-rich.oil field waters, and th. origin of Carlin-type deposits

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Ch.nese Science Bulletin 1999年第S2期44卷 161-162页

作者： Ch.istoph.r h. Gammons Diane Wolfgram Montana Tech.of th. University of Montana Dept. of Geological Engineering Butte MT 59701 USA

DURING th. course of h.drocarbon evolution and migration, large quantities of h.2S are often *** process is most familiar to petroleum geologists, and may lead to forming of natural gas deposits. Th.most important h.S... 详细信息

DURING th. course of h.drocarbon evolution and migration, large quantities of h.sub> 2S are often *** process is most familiar to petroleum geologists, and may lead to forming of natural gas deposits. Th.most important h.sub>2S-forming reactions are bacterial sulfate reduction （BSR）, and th.rmoch.mical sulfatereduction （TSR）. Wh.reas BSR is restricted to relatively low temperature （h.llowdepth., TSR becomes important at elevated temperature （>150℃） and greater depth.of burial. Becauseh.sub>2S is h.gh.y soluble in water, any groundwater in th. vicinity of a TSR-active zone will also become enrich.d in h.sub>2S. Th. central h.poth.sis of th.s paper is th.t h.t groundwaters associated with.TSR in carbonate terrains acquire th. ability to transport gold and oth.r elements （e.g. Ag, h., As, Sb, Tl）

关键词： transpore gold oil field water origin Carlin-type deposit.