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Insect host-parasite coevolution in the lig.t of experimental evolution

1999年

作者： James g. Mann y. A. Liu.

来源：畅想之星图书光盘版（南... 评论

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Insect Science 2014年第4期21卷 401-414页

作者： Niels A. g. Kerstes Oliver y. Martin Experimental Ecolog. Institute for Integrative Biology D-USYS ETH Zurich

The many.way. parasites can impact their host species have been the focus of intense study.using.a rang. of approaches. A particularly.promising.but under-used method in this context is experimental evolution, because it allows targ.ted manipulation of known populations exposed to contrasting.conditions. The strong.potential of apply.ng.this method to the study.of insect hosts and their associated parasites is demonstrated by.the few available long.term experiments where insects have been exposed to parasites. In this review, we summarize these studies, which have delivered valuable insig.ts into the evolution of resistance in response to parasite pressure, the underly.ng.mechanisms, as well as correlated g.netic responses. We further assess finding. from relevant artificial selection studies in the interrelated contexts of immunity. life history. and reproduction. In addition, we discuss a number of well-studied Tribolium castaneum-Nosema whitei coevolution experiments in more detail and provide sug.estions for research. Specifically. we sug.est that future experiments should also be performed using.nonmodel hosts and should incorporate contrasting.experimental conditions, such as population sizes or envi- ronments. Finally. we expect that adding.a third partner, for example, a second parasite or sy.biont, to a host-parasite sy.tem could strong.y.impact （co）evolutionary.dy.amics.

关键词： artificial selection immunity Nosema reproduction resistance Tribolium

INVESTIg.TION ON HOT DUCTILITy.AND STRENg.H OF CONTINUOUS CASTINg.SLAB FOR AH32 STEEL

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Acta Metallurg.ca Sinica(Eng.ish Letters) 2006年第1期19卷 75-78页

作者： g. y. Li X.F. Li L.g. Ao Technolog. Center Anshan Iron and Steel Group CorporationAnshan 114009 China

By.means of g.eeble-1500 testing.machine, the simulation of continuous casting.process forAH32 steel was carried out and hot ductility.and streng.h were determined. The cracking.sensitivity.was studied under the different temperatures and strain rates. The Precipitations of AIN at different temperatures and the fractures of hig.-temperature tensile samples were observed by.using.TEM （transmission electron microscope） and SEM （scanning.electron microscope）. The factors affecting.the brittle temperature zone were discussed.

关键词： continuous casting.slab brittle temperature zone tensile streng.h,ductility simulation

Quality.vs. quantity.of publications in nanotechnolog. field from the People’s Republic of China

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Chinese Science Bulletin 2008年第8期53卷 1272-1280页

作者： Ronald N. KOSTOFF Ry.n B. BARTH Clifford g. y. LAU Office of Naval Research 875 N. Randolph St. Arlington 22217 VA USA DDL-OMNI Eng.neering LLC 8260 Greensboro Drive Suite 600 McLean VA USA Institute for Defense Analy.es 4850 Mark Center Drive Alexandria VA USA

This study.evaluates trends in quality.of nanotechnolog. and nanoscience papers produced by.au- thors from the People’s Republic of China (PRC). The metric used to g.ug. quality.is ratio of hig.ly.cited nanotechnolog. papers to total nanotechnolog. papers produced in sequential time frames. The USA is both the most prolific nanotechnolog. publishing.country.and most represented country.on hig.ly.cited nanotechnolog. papers (both in absolute numbers of hig.ly.cited papers and hig.ly.cited papers relative to total publications) over the 1998―2003 time frame, based on the SCI/SSCI databases. Some of the smaller hi-tech countries have relatively.hig. ratios (~2) of hig.ly.cited papers to total publications (e.g. Denmark, Netherlands, Switzerland). Countries that have exhibited rapid g.owth in SCI/SSCI nanotechnolog. paper production in recent y.ars (e.g. PRC, South Korea) had ratios an order of mag.itude less than that of the USA for 1998, but by.2003 had increased to about 20% that of the USA (~2.5). PRC and South Korea have climbed in the publications ranking. from 6th and 9th in 1998, re- spectively. to 2nd and 6th in 2005, respectively. PRC’s ratio monotonically.increased from 0.16 to 0.45 over the 1998―2003 period, and South Korea’s ratio increased from 0.11 to about 0.6 over that same period, indicating.their papers are g.tting.more and more citations proportionately. Thus, under rapid g.owth conditions, PRC and South Korea have been able to increase their share of participation in hig.ly.cited papers. As of 2003, PRC and South Korea have ratios comparable to nations like Japan, France, Italy. and Australia but not y.t approaching.those of the hig.ly.cited countries. None of the top ten publications producing.institutions are from the USA, while all of the top ten hig.ly.cited publica- tions producers are from the USA. Over the 1998―2003 time period, the top six total publications pro- ducing.institutions (g.obally. remained the same, with Chinese Academy.of Scien

关键词：纳米技术纳米科学引用分析中国

STUDy.ON THE HOT DEFORMATION BEHAVIORS OF Al-Zn-Mg.Cu-Cr ALUMINUM ALLOy

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Acta Metallurg.ca Sinica(Eng.ish Letters) 2008年第2期21卷 109-115页

作者： g. y. Lin Z.F. Zhang.H. Zhang.D.S. Peng.J. Zhou School of Materials Science and Eng.neering Central South University Changsha 410083 China

The hot deformation behaviors and microstructures of A1-Zn-Mg.Cu-Cr aluminum alloy.have been studied using.thermal simulation test, optical microscopy.and transmission electron microscopy. As a result, the true stress versus true strain curves and the microstructures under various deformation conditions are obtained. The microstructures g.adually.incline to dy.amic-recry.tallization with the deformation temperature rising.and the recry.tallization g.ains refine with the decrease of deformation temperature or with raising.the strain rates. The quantitative relationship between the Zener-Hollomon parameter （Z） and averag. recry.tallization g.ain size in the subsequent heat treatment is set up.

关键词： A1-Zn-Mg.Cu-Cr aluminum alloy Hot deformation True stressvs true strain curve Microstructure

Mid-Infrared Lasers With Low Threshold and Photodetectors

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光学学报 2003年第S1期23卷 323-324页

作者： A. Z. Li H. Li y. g. Zhang.X. Zhang.y. L. Zheng.g. y. Xu M. Qi C. g.achl M. L. Peabody.A. y. Cho State Key.Laboratory.of Functional Materials foe Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Rd. Shanghai 200050 China Bell Laboratories Lucent Technologies 600 Mountain Avenue Murray HillNJ 07974 USA

We report the g.owth, fabrication, and operation of 2.0μm Ing.AsSb/Alg.AsSb laser diodes and 8.5μm g.InAs/AlInAs quantum cascade lasers with low threshold current and the latest improvements in the performance of In... 详细信息

关键词： threshold current laser diodes the g.owth

g.AIN g.OWINg.Dy.AMICS OF Mg.-CaO COMPOSITE CERAMICS

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Acta Metallurg.ca Sinica(Eng.ish Letters) 2000年第6期13卷 1155-1158页

作者： T.M. Jia and g. y. An (Harbin University.of Technolog., Harbin 150001, China) S.X. Che (Liaoning.Institute of Technolog., Jinzhou 121000, China) Harbin Univ. of Technol. Harbin 150001 China

The g.ain g.owing.dy.amics including.the g.owing.process, the g.owing.exponent and the g.owing.activation energ. is obtained for the Mg.-CaO composite ceramics with the additions of Fe2O3, CeO2 and/or ZrO2 as fluxes by.measuring.the size of g.ains with the method of Straig.t Line Across. The results show that all of the additions, in which Fe2O3 is the strong.st, have notable effects on the g.ain g.owing.dy.amics by.reducing.the g.owing.activation energ. and promoting.the g.ain g.owing. The research g.ves a g.od reference for the additions of fluxes to the matrix of ceramic filter.

关键词： Mg.-CaO composite ceramics g.owing.exponent activation energ.

Experimental Evaluation of the Attenuation Effect of a Passive Damper on a Road Vehicle Bumper

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World Journal of Eng.neering.and Technolog. 2014年第3期2卷 192-200页

作者： A. Ag.ei-Ag.emang.g. y. Obeng.P. y. Andoh Department of Mechanical Eng.neering College of Engineering Kwame Nkrumah University of Science and Technology (KNUST) Kumasi Ghana Technolog. Consultancy.Centre College of Engineering Kwame Nkrumah University of Science and Technology (KNUST) Kumasi Ghana

To mitig.te the deg.ee of damag. to passeng.rs caused by.automobile collisions, a friction damper was built and used in experimental tests to test its effectiveness in impact energ. attenuation. The study.revealed that energ. absorption capacity.of a bumper can be improved with the addition of a friction damper. The results revealed that the addition of the friction damper to an automobile bumper to g.ve a bumper-damper sy.tem could attenuate about 32.5 % more energ. than with the bumper alone. It can be concluded that the effectiveness of automobile bumpers to withstand impact of vehicles by.absorbing.the kinetic energ. from the impact can be improved with the use of a passive friction damper. That is, a passive friction damper sy.tem could be used to attenuate more road vehicle impact energ. in collisions.

关键词： Vehicle Bumper Equivalent Energ. Speed (EES) Impact Attenuation Passive Damper

Artificial-intellig.nt-powered safety.and efficiency.improvement for controlling.and scheduling.in integ.ated railway.sy.tems

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Hig.-speed Railway 2024年第3期2卷 172-179页

作者： Liu J. Liu g. Wang.y. Zhang.W. Beijing.National Railway.Research & Desig. Institute of Sig.al & Communication g.oup Co. Ltd Beijing 100070 China Eng.neering.Research Center of Railway.Industry.of Intellig.nt and Autonomous Train Control Beijing 100070 China

The multi-mode integ.ated railway.sy.tem, anchored by.the hig.-speed railway. caters to the diverse travel requirements both within and between cities, offering.safe, comfortable, punctual, and eco-friendly.transportation services. With the expansion of the railway.networks, enhancing.the efficiency.and safety.of the comprehensive sy.tem has become a crucial issue in the advanced development of railway.transportation. In lig.t of the prevailing.application of artificial intellig.nce technolog.es within railway.sy.tems, this study.leverag.s larg. model technolog. characterized by.robust learning.capabilities, efficient associative abilities, and linkag. analy.is to propose an Artificial-intellig.nt (AI)-powered railway.control and dispatching.sy.tem. This sy.tem is elaborately.desig.ed with four core functions, including.g.obal optimum unattended dispatching. sy.erg.tic transportation in multiple modes, hig.-speed automatic control, and precise maintenance decision and execution. The deploy.ent pathway.and essential tasks of the sy.tem are further delineated, along.ide the challeng.s and obstacles encountered. The AI-powered sy.tem promises a sig.ificant enhancement in the operational efficiency.and safety.of the composite railway.sy.tem, ensuring.a more effective alig.ment between transportation services and passeng.r demands. © 2024 Beijing.Jiaotong.University

关键词： Artificial intellig.nce Hig.-speed railway Larg.-scale mode, sy.tem framework Multi-mode railway.sy.tem Safety.and efficiency.improvement

Restoration of Damag.d Ecosy.tem Services on Wetlands in Northern Part of the Volg.-Akhtuba Floodplain (Russia)

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Journal of g.oscience and Environment Protection 2015年第6期3卷 6-10页

作者： A. V. Lukonina g. y. Klinkova N. B. Lopantzeva Botanic g.rden of “Volg.g.ad State Socio-Pedag.g.cal University. Volgograd Russia Chair of Park-and-g.rden and Landscape Construction of “Volg.g.ad State Socio-Pedag.g.cal University. Volgograd Russia Lower Volg. and Northern Caspian Reg.on of UNDP/g.F-MNR RF Project “Mainstreaming.Biodiversity.Conservation into Russia’s Energ. Sector Policies and Operations” Volgograd Russia

Due to the reg.lation of the river Volg. flow, expanding.of the territories intended for construction and development of ag.iculture wetlands Volg.-Akhtuba floodplain are being.sig.ificantly.transformed and are losing.many.of their qualities. Non-reg.lated loads lead to the break of natural phy.ical and chemical characteristics of water bodies, loss of biodiversity. deg.adation of structure and functions of biolog.cal communities and, as a result, to decreasing.of potential ecosy.tem services. Restoration of the lost qualities of water ecosy.tems is a key.factor in increasing.sustainability.of reclaimed landscapes and creating.comfortable conditions for living.of locals and their economic activity. On the territory.of the biosphere reserve “Nature park” “Volg.-Akhtuba floodplain” a number of model sites were defined in order for research projects and practical work on restoration of deg.aded landscapes to be executed. The widest rang. of the lost ecosy.tem qualities is being.restored during.work on Lake Zapornoy.. Restoration of ecosy.tem functions is being.implemented according.to the main economic activities carried out in this area. Ecosy.tem services of the area are specified in accordance with its functional purpose. The existing.landscape and ecolog. conditions have been studied and estimated to see if the planned ecosy.tem services can be provided. The project sug.ests the following.activities: restoration of hy.ro-morpholog.cal characteristics, reconstruction of habitats for biodiversity.and their ecosy.tem services, improvement to restore and preserve recreational qualities of landscape. The project includes the monitoring.the effectiveness of restoration. Monitoring.prog.am is based on indices of environmental assessment.

关键词： Restoration of Wetlands Ecosy.tem Services the Volg.-Akhtuba Floodplain