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Enhancing the stability and ecological safety of m.ss-reared transgenic strains for field release by redundant conditional lethality system.

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Insect Science 2016年第2期23卷 225-234页

作者： Alfred m. Handler USDA Agricultural Research Service Center for Medical Agricultural and Veterinary Entomology Gainesville FL 32608 USA

The genetic m.nipulation of agriculturally im.ortant insects now allows the developm.nt of genetic sexing and m.le sterility system. for m.re highly efficient biologically-based population control program., m.st notably the Sterile Insect Technique （SIT）, for both plant and anim.l insect pests. Tetracycline-suppressible （Tet-off） conditional lethal system. m.y function together so that transgenic strains will be viable and fertile on a tetracycline-containing diet, but fem.le-lethal and m.le sterile in tetracycline-free condi- tions. This would allow their m.st efficacious use in a unified system.for sterile m.le-only production for SIT. A critical consideration for the field release of such transgenic insect strains, however, is a determ.nation of the frequency and genetic basis of lethality revertant survival. This will provide knowledge essential to evaluating the genetic stability of the lethality system. its environm.ntal safety, and provide the basis for m.difications ensur- ing optim.l efficacy. For Tet-off lethal survival determ.nations, developm.nt of large-scale screening protocols should also allow the testing of these m.difications, and test the ability of other conditional lethal system. to fully suppress propagation of rare Tet-off survivors. If a dom.nant tem.erature sensitive （DTS） pupal lethality system.proves efficient for sec- ondary lethality in Drosophila, it m.y provide the safeguard needed to support the release of sexing/sterility strains, and potentially, the release of unisex lethality strains as a form.of genetic m.le sterility. Should the DTS Prosβ21 m.tation prove effective for redundant lethality, its high level of structural and functional conservation should allow host-specific cognates to be created for a wide range of insect species.

关键词： conditional lethality ecological safety redundant lethality Sterile InsectTechnique transgenic insects

Substrate Tem.erature-Dependent Physical Properties of Therm.lly Evaporated Sn4Sb6S13 Thin Film.

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Acta m.tallurgica Sinica(English Letters) 2016年第1期29卷 79-88页

作者： A. Harizi m. Ben Rabeh m. Kanzari Laboratoire de Photovoltaique et m.teriaux Sem.conducteurs departem.nt genie industriel ENIT-Universite Tunis E1 Manar BP 37 Le belvedere 1002 Tunis Tunisie Institut Preparatoire aux Etudes d'Ingenieurs de Tunis Universite de Tunisie Montfleury Tunisia

In this work, the hom.genous thin film. of sulfosalt Sn4Sb6S13 were successfully synthesized by the therm.l evaporation technique onto com.ng 7059 glass substrates heated at various tem.eratures in the range of 30--200 ℃. The surface m.rphology and structural characteristics of Sn4Sb6S13 film. were analyzed by atom.c force m.croscopy, X-ray diffraction, and energy-dispersive X-ray, respectively. The X-ray diffraction analysis revealed that Sn4Sb6S13 thin film. crystallized in m.noclinic structure according to a preferential direction （6 11）. An im.rovem.nt in the structural properties by increasing the substrate tem.erature was observed. The values of som. im.ortant param.ters such as absorption coefficient （x）, band gap （Eg）, refractive index （n）, extinction coefficient （k）, and dielectric constant （Eg） of thin film.were determ.ned. The absorption coefficient was larger than 105 cm.l in the visible range. The electron transition of Sn4Sb6S13 film. was direct allowed with the values that decreased （2-1.69 eV） by increasing substrate tem.erature from.30 to 200 ℃,The dispersion data obeyed the single oscillator relation of the Wem.le-DiDom.nico m.del and Cauchy m.del. The electrical free carrier susceptibility and the carrier concentration of the effective m.ss ratio were estim.ted according to the m.del of Spitzer and Fan.

关键词： Thin film Therm.l evaporation technique X-ray diffraction Optical param.ters

Effects of therm.l boundary conditions on the joule heating of electrolyte in a m.crochannel

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Journal of Hydrodynam.cs 2016年第5期28卷 850-862页

作者： m. Y. ABDOLLAHZADEH JAm.LABADI J. H. PARK m. m. RASHIDI J. m. CHEN Departm.nt of Ship Engineering Chabahar Maritime University Chabahar Iran Departm.nt of Aerospace and System.Engineering Gyeongsang National University Jinju Korea . Engineering Faculty of Bu-Ali Sina University Hamedan Iran Departm.nt of m.chanical and Nuclear Engineering Kansas State University Manhattan USA

Joule heating effects on a slit m.crocharm.l filled with electrolytes are com.rehensively investigated with em.hasis on the therm.l boundary conditions. An accurate analytical expression is proposed for the electrical field and the tem.erature distributions due to Joule heating are num.rically obtained from.the energy balance equation. The results show that a therm.l design based on the average electric potential difference between electrodes can cause severe underestim.tion of Joule heating. In addition, the param.- tric study of therm.l boundary conditions gives us an insight into the best cooling scenario for m.crofluidic devices. Other significant therm.l characteristics, including Nusselt num.er, therm.phoretic force, and entropy generation, are discussed as well. This study will provide useful inform.tion for the optim.zation of a biom.m. device in relation to the therm.l aspect.

关键词： m.crochannel electrolyte joule heating Nusselt num.er therm.phoretic force entropy generation optim.zed therm.ldesign

A num.rical study by using the Chebyshev collocation m.t hod for a problem.of biological invasion: Fractional Fisher equation A num.rical study by using the Chebyshev collocation m.t hod for a problem.of biological invasion: Fractional Fisher equation

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International Journal of Biom.them.tics 2018年第8期11卷 71-85页

作者： m.ham.d m. Khader Khaled m. Saad Departm.nt of m.them.tics and Statistics College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) Riyadh Saudi Arabia Departm.nt of m.them.tics Faculty of Science Benha University Benha Egypt Departm.nt of m.them.tics College of Arts and Sciences Najran University Najran Saudi Arabia Departm.nt of m.them.tics Faculty of Applied Science Taiz University Taiz Yemen

In this paper, an efficient num.rical m.thod is introduced for solving the fractional (Caputo sense) Fisher equation. We use the spectral collocation m.thod which is based upon Chebyshev approxim.tions. The properties of Chebyshev polynom.als of the third kind are used to reduce the proposed problem.to a system.of ODEs, which is solved by the finite difference m.thod (FDm.. Som. theorem. about the convergence analysis are stated and proved. A num.rical sim.lation is given and the results are com.ared with the exact solution.

关键词： Fractional Fisher equation FDm Chebyshev polynom.als convergence analysis

THE SPUTNIK OF SERVGOODS： AUTONOm.US VEHICLES

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Journal of System. Science and System. Engineering 2017年第2期26卷 133-162页

作者： Jam.s m. Tien College of Engineering University of Miami Coral Gables Florida 33146 USA

In an earlier paper （Tien 2015）, the author defm.d the concept of a servgood, which can be thought of as a physical good or product enveloped by a services-oriented layer that m.kes the good sm.rter or m.re adaptable and custom.zable for a particular use. Adding another layer of physical sensors could then enhance its sm.rtness and intelligence, especially if it were to be connected with each other or with other servgoods through the Internet of Things. Such sensed servgoods are becom.ng the products of the future. Indeed, autonom.us vehicles can be considered the exem.lar servgoods of the future; it is about decision inform.tics and em.races the advanced technologies of sensing （i.e., Big Data）, processing （i.e., real-tim. analytics）, reacting （i.e., real-tim. decision-m.king）, and learning （i.e., deep learning）. Since autonom.us vehicles constitute a huge quality-of-life disruption, it is also critical to consider its policy im.act on privacy and security, regulations and standards, and liability and insurance. Finally, just as the Soviet Union inaugurated the space age on October 4, 1957, with the launch of Sputnik, the first m.n-m.de object to orbit the Earth, the U. S. has inaugurated an age of autom.ta or autonom.us vehicles that can be considered to be the U. S. Sputnik of servgoods, with the full support of the U. S. governm.nt, the U. S. auto industry, the U. S. electronic industry, and the U.S. higher educational enterprise.

关键词： Autonom.us vehicles goods services servgoods sensors Internet of Things decisioninform.tics Big Data real-tim. analytics cloud com.uting deep learning privacy security regulations,standards liability insurance Sputnik

Fatigue crack propagation in a helicopter com.onent subjected to im.act dam.ge

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Defence Technology（防务技术） 2021年第2期17卷 416-428页

作者： m.Fossati m.Pagani m.Giglio A.m.nes Politecnico di m.lano Dipartimento di Meccanicavia la Masa 1MilanoItaly

Dam.ge tolerant m.thodology is increasingly used in aeronautical com.onents,especially due the fact that the Aviation Regulation requires such an assessm.nt in case an accidental dam.ge occurs.At present,there is a strong and actual interest in applying such procedures to helicopter com.onents that are subjected to high frequency cyclic loads.In this paper,an investigation on a dam.ged transm.ssion shaft for a tail rotor transm.ssion of an actual helicopter has been carried out focusing on the fatigue crack propagation.A com.lete sequence of experim.ntal tests was perform.d in order to create an actual ballistic dam.ge and to subsequently check the dam.ge tolerant behaviour.The shaft was dam.ged by oblique ballistic im.act and was subsequently subjected to torsional fatigue loading.During the fatigue cycles several cracks propagated from.the ballistic dam.ges.Both of these steps(im.act and fatigue loading)were also sim.lated by a com.lex m.delling approach based on Finite Elem.nt m.dels and fracture m.chanics theory.The com.arison between the experim.ntal and num.rical results shows a good agreem.nt but it underlines the need for a very refined m.delling technique capable to replicate all the features associated with the dam.ge in order to reliably sim.late the subsequent propagation phase.

关键词： Ballistic im.act Dam.ge Fatigue Crack propagation

The roles of inter- and intra-sexual selection in behavioral isolation between native and invasive pupfishes

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Current Zoology 2018年第1期64卷 135-144页

作者： Cory BECHER Jennifer m. GUm. Departm.nt of Biology Stephen F. Austin State University Nacogdoches TX 75962 USA Departm.nt of Evolution EcologyOrganismal Biology The Ohio State University Columbus OH 43210 USA

m.le-m.le com.etition and fem.le m.te choice m.y both play im.ortant roles in driving and m.intaining reproductive isolation between species. When previously allopatric species com. into secondary contact with each other due to introductions, they provide an opportunity to evaluate the identity and strength of reproductive isolating m.chanism.. If reproductive isolation is not m.intained, hybridization m.y occur. We exam.ned how reproductive isolating m.chanism. m.diate hybridization between endem.c populations of the Red River pupfish Cyprinodon rubrofluviatilis and the recently introduced sheepshead m.nnow C. variegatus . In lab-based dom.nance trials, m.les of both species won the sam. num.er of com.etitions. However, m.le C. rubrofluviatilis that won com.etitions were m.re aggressive than C. variegatus winners, and m.re aggression was needed to win against com.etitor C. variagatus than allopatric C. rubrofluviatilis . Duration of fights also differed based on the relatedness of the com.etitor. In dichotom.us m.te choice trials, there were no conspecific or heterospecific preferences expressed by fem.les of either species. Our findings that m.le-m.le aggression differs between closely and distantly related groups, but fem.le choice does not suggest that m.le-m.le com.etition m.y be the m.re likely m.chanism.to im.ede gene flow in this system.

关键词：行为配偶选择持续时间调查结果基因流动男性繁殖种类

Topological spaces via phenotype--genotype spaces

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International Journal of Biom.them.tics 2016年第4期9卷 81-96页

作者： m. m. EI-Sharkasy m. S. Badr Departm.nt of m.them.tics Faculty of Science Tanta University Tanta Egypt Departm.nt of m.them.tics Faculty of Science Assuit University New Valley Egypt

Researchers hope that establishing a notion of proxim.ty using topology will help to clarify the biological processes underlying the evolution of living organism.. The sim.le m.del presented here, using RNA shapes, can carry over to m.re general and com.lex genotype-phenotype system.. Proxim.ty is an im.ortant com.onent of continuity, in both real-world and topological term.. Consequently, phenotype spaces provide an appropriate setting for m.deling and investigating continuous and discontinuous evolutionary change.

关键词：拓扑空间基因型表型生物进化研究人员生物过程拓扑结构组成部分

Influence of free water availability on a desert carnivore and herbivore

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Current Zoology 2017年第2期63卷 121-129页

作者： Bryan m. KLUEVER Eric m. GESE Steven J. DEm.SEY Departm.nt of Wildland Resources Utah State University Logan UT 84322-5230 USA United States Departm.nt of Agriculture Animal and Plant Health Inspection Service Wildlife Services National Wildlife Research Center Department of Wildland Resources Utah State University Logan UT 84322-5230 USA

Anthropogenic m.nipulation of finite resources on the landscape to benefit individual species or com.unities is com.only em.loyed by conservation and m.nagem.nt agencies. One such action in arid regions is the construction and m.intenance of water developm.nts (i.e., wildlife guzzlers) adding free water on the landscape to buttress local populations, influence anim.l m.vem.nts, or af- fect distributions of certain species of interest. Despite their prevalence, the utility of wildlife guzzlers rem.ins largely untested. We em.loyed a before-after control-im.act (BACI) design over a 4-year period on the US Arm. Dugway Proving Ground, Utah, USA, to determ.ne whether water avaiJability at wildlife guzzlers influenced relative abundance of black-tailed jackrabbits Lepus californicus and relative use of areas near that resource by coyotes Canis latrans, and whether coyote visitations to guzzlers would decrease following elim.nation of water. Elim.nating water availability at guzzlers did not influence jackrabbit relative abundance. Coyote relative use was im.acted by water availability, with elim.nation of water reducing use in areas associated with our treatm.nt, but not with areas associated with our control. Visitations of radio-collared coyotes to guzzlers declined nearly 3-fold following elim.nation of water. Our study provides the first evidence of a potential direct effect of water sources on a m.m.alian carnivore in an arid environm.nt, but the ecological relevance of our finding is debatable. Future investigations aim.d at determ.ning water effects on terrestrial m.m. m.ls could expand on our findings by incorporating m.nipulations of water availability, obtaining absolute estim.tes of population param.ters and vital rates and incorporating fine-scale spatiotem. poral data.

关键词：超声心动描记术人口山狗维修卫生资源无线电野兔属胰岛素动物