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Incipient sexual isolation in laupala cerasina： Females discriminate population-level divergence in acoustic characters

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Current Zoology 2012年第3期58卷 416-425页

作者： Jaime l. GRACE Kerry l. SHAW Department of Biology University of Maryland College Park MD 20742 USA Department of Neurobiology and Behavior Cornel1 University Ithaca NY 14853 USA kls4@cornell.edu

Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual selection occurs when evolution in traits and preferences within populations causes differentiation among populations, such that females in alternative populations prefer sexual signals of their own population relative to others. Differentiated traits and preferences thereby play an active role in limiting gene flow between divergent populations. The effectiveness of differentiated preferences in maintaining differentiated male signals against the homogenizing effects of gene flow across populations will be limited by both the degree to which fe- males can discriminate against non-local males, and the breeding values of traits and preferences. Populations of the Hawaiian cricket laupala cerasina have diverged in pulse rate, a sexually selected male signal, and female acoustic preference for pulse rate. Gene flow between neighboring populations may be reduced if migrants from sexually diverged populations experience re- duced mating success. We show that females discriminate among divergent songs characteristic of neighboring populations, that differences among populations in song and preference breed true in a common environment, and that mean preferences for each population closely match the mean pulse rates. Divergence in preference was observed only between populations that also dif- fered in song. Along with a striking ability to discriminate slight differences in song, correlated evolution of song and preference within populations could be a mechanism that promotes assortative mating among populations, thereby reducing gene flow, and leading to speciation in laupala [Current Zoology 58 （3）： 416-425, 2012].

关键词： Sexual selection Phenotypic divergence Behavioral isolation Preference functions Speciation

Integrating small mammal community variables into aircraft–wildlife collision management plans at Namibian airports

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Integrative Zoology 2015年第6期10卷 515-530页

作者： Morgan l.HAUPTFlEISCH Nico l.AVENANT Department of Agriculture and Natural Resources Sciences Polytechnic of NamibiaWindhoekNamibia Department of Mammalogy National Museumand Centre for Environmental ManagementUniversity of the Free StateBloemfonteinSouth Africa

Understanding ecosystems within and around airports can help to determine the causes and possible mitigation measures for collisions between aircraft and *** mammal communities are an important component of the semi-arid savanna ecosystems of Namibia,its productivity and its ecosystem *** are also a major direct attractant for raptors at *** present study compared the abundance and diversity of small mammals between Namibia’s 2 main airport properties(Hosea Kutako International Airport and Eros Airport),and among areas of land used for various purposes surrounding the airports.A total of 2150 small mammals(3 orders,11 species)were captured over 4 trapping *** mammal abundance was significantly higher at the end of the growing season than during the non-growing *** grass mowing regimen in current management plans at the airports resulted in a significant reduction of small mammal abundance at Hosea Kutako during the non-growing season only,thus indicating that annual mowing is effective but insufficient to reduce the overall abundance of mammal prey species for *** mammal numbers were significantly higher at Hosea Kutako Airport compared to the cattle and game farming land surrounding the airport,while no differences in small mammal densities or diversity were found for areas with different land uses at and surrounding *** study suggests that the fence around Hosea Kutako provides a refuge for small mammals,resulting in higher *** also indicates that different surrounding land use practices result in altered ecosystem function and productivity,an important consideration when identifying wildlife attractants at airports.

关键词： airport ecosystems bird strike risk Namibia small mammal indicators

Frictionally excited thermoelastic dynamic instability of functionally graded materials

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Acta Mechanica Sinica 2019年第1期35卷 99-111,I0004页

作者： J.liu l.l.Ke Y.S.Wang College of Engineering Huazhong Agricultural UniversityWuhan 430070China Institute of Engineering Mechanics Beijing JiaotongUniversity Beijing 100044China

The perturbation method is applied to investigate the frictionally excited thermoelastic dynamic instability (TEDI) of a functionally graded material (FGM) coating in half-plane sliding against a homogeneous half-plane. We assume that the thermoelastic properties of the FGM vary exponentially with thickness. We also examine the effects of the gradient index, sliding speed, and friction coefficient on the TEDI for various material combinations. The transverse normal stress for two different coating structures is calculated. Furthermore, the frictional sliding stability of two different coating structures is analyzed. The obtained results show that use of FGM coatings can improve the TEDI of this sliding system and reduce the possibility of interfacial failure by controlling the interfacial tensile stress.

关键词： Thermoelastic dynamic instability Frictional heat Functionally graded materials Stress analysis

Grafting affects yield and phenolic prof ile of Solanum melongena l. landraces

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Journal of Integrative Agriculture 2016年第5期15卷 1017-1024页

作者： l Sabatino G Iapichino A Maggio E D’ Anna M Bruno F D’ Anna Department of Agricultural and Forest Sciences University of Palermo Department of Biological Chemical and Pharmaceutical Sciences and Technologies University of Palermo Regional Centres for Agricultural Technologies (Ce.R.T.A.) University of Foggia

The influence of grafting on agronomical and qualitative characteristics of four Sicilian eggplant landraces was investigated. Grafted and ungrafted plants were compared in the open field in the northern coast of Sicily. Solanum torvum seedlings were used as rootstock. Regardless of genotypes tested, grafting significantly increased total fruit production, marketable production, and number of marketable fruits, but did not affect weight of marketable fruits and waste production. landrace 2（Sciacca）, with black epidermal tissue and pyriform fruit shape, when grafted onto S. torvum not only gave a higher yield performance than ungrafted plants, but also showed a higher phenolic antioxidant content. landrace 4（Sicilia）, with black epidermal tissue and small cylindrical fruits also benefited, when grafted onto S. torvum, from a substantial increase in antioxidant fruit content. As consumers＇ demand for fruits and vegetables rich in compounds important for human health is steadily increasing, these landrace/rootstock combinations should deserve more attention by plant nurseries involved in grafted seedling production and interested in the valorization and conservation of eggplant biodiversity.

关键词： eggplant propagation technique yield polyphenols HPlC analysis

Novel heating-and deformation-induced phase transitions and mechanical properties for multicomponent Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=Fe,Co,Ni,Cu)amorphous alloys

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Journal of Materials Science & Technology 2022年第9期104卷 109-118页

作者： J.Ding A.Inoue F.l.Kong S.l.Zhu Y.l.Pu E.Shalaan A.A.Al-Ghamdi A.l.Greer School of Materials Science and Engineering Tianjin UniversityTianjin 300072China International Institute of Green Materials Josai International UniversityTogane 283-8555Japan Institute of Massive Amorphous Alloy Science China University of Mining TechnologyXuzhou 221116China Department of Physics King Abdulaziz UniversityJeddah 22254Saudi Arabia MISiS National University of Science and TechnologyMoscow 119049Russia School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Department of Materials Science and Metallurgy University of CambridgeCambridge CB30FSUK

Multicomponent alloys of Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=Fe,Co,Ni,Cu)can be melt-spun to obtain amorphous *** maximum thickness for fully amorphous ribbons varies with composition in the range 34-53μ*** contrast,fully amorphous ribbons are not obtainable for binary Zr_(50)Ni_(50)or ternary Zr_(50)(Ni,Cu)_(50)***-induced crystallization occurs through:two stages of amorphous[am]→[~(am')+B2]→[B2+B33]for Zr_(50)M_(50);and[am]→[am'+B2]→[B2+AgZr]for Zr_(50)(M,Ag)_(50);and a single stage of[am]→[B2]for Zr_(50)(M,Pd)_(50),while no B2 phase is formed for the binary and ternary Zr_(50)Q_(50)(Q=Ni or/and Cu)***-spun amorphous ribbons have good bending ***,Zr_(50)M_(50)ribbons in tension show 0.22-0.28%plastic elongation and work-hardening(the yield stress is~820 MPa,the fracture stress is~1200 MPa).When cold-rolled at room temperature to 30%reduction in thickness,Zr_(50)M_(50)ribbons show 10%increase in hardness,while retaining good bending ***-rolling induces precipitation of spheroidal B2 and irregular B33 particles,while deformation in tension induces B2,B33 and also plate-like monoclinic *** B2 and B33 particles form by polymorphic transformation,and include a high density of internal *** novel deformationinduced precipitation has not been recognized for any Zr_(50)Q_(50)binary or ternary *** new multicomponent systems are encouraging for future progress as structural amorphous alloys.

关键词： Multicomponent Microstructure Mechanical properties Phase transition Amorphous alloy

A Reinvestigation of the Physical Properties of Pismis 3 based on 2MASS Photometry

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Chinese Journal of Astronomy and Astrophysics 2008年第3期8卷 362-368页

作者： Tadross A.l. National Research Institute of Astronomy and Geophysics 11421-HelwanCairoEgypt

As a continuation of a series of work, we aim to refine and re-determine the physical parameters of previously rarely or un-studied open star clusters with good quality CMDs using Near-IR JHK photometry. Here we present a morphological analysis of the 2MASS database （the digital ＂Two Micron All Sky Survey＂） for the open cluster Pismis 3. Some of the physical parameters are estimated for the first time, and some others, re-determined.

关键词： techniques photometric -- Galaxy open clusters and associations -- stars luminosity function -- stellar clusters individual Pismis 3

An Alternative to Free Entropy for Free Group Factors

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Acta Mathematica Sinica,English Series 2003年第3期19卷 419-472页

作者： MichalDOST/~l DonHADWIN Mexicka4 Praha10CZ-10100CzechRepublic DepartmentofMathematics UniversityofNewHampshireDurhamNH03824-3591USA

In this paper we define a very simple invariant η(V^-) for a k-tuple V^-of unitaries in a finite factor von Neumann algebra, and we show how this invariant can replace free entropy in many of the important applications. We also introduce a notion of metric free entropy and some related *** include proofs, using η, of the theorems of liming Ge and of D. Voiculescu, respectively, on the primeness of and on the absence of Cartan snbalgebras in the noncommutative free group factors.

关键词： FREE groups AlGEBRA

Existence for a Class of Non-Newtonian Fluids with a Nonlocal Friction Boundary Condition

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Acta Mathematica Sinica,English Series 2006年第2期22卷 523-534页

作者： l.CONSIGlIERI Department of Mathematics and CMAF Sciences Faculty of University of Lisbon 1749-016 Lisboa Portugal

We deal with a variational inequality describing the motion of incompressible fluids, whose viscous stress tensors belong to the subdifferential of a functional at the point given by the symmetric part of the velocity gradient, with a nonlocal friction condition on a part of the boundary obtained by a generalized mollification of the stresses. We establish an existence result of a solution to the nonlocal friction problem for this class of non-Newtonian flows. The result is based on the Faedo-Galerkin and Moreau Yosida methods, the duality theory of convex analysis and the Tychonov-Kakutani-Glicksberg fixed point theorem for multi-valued mappings in an appropriate functional space framework.

关键词： Non-Newtonian fluids Coulomb and nonlocal friction

Acoustic Velocities and Elastic Properties of Pyrite (FeS2) to 9.6 GPa

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Journal of Earth Science 2010年第5期21卷 792-800页

作者： Matthew l Whitaker Mineral Physics Institute Stony Brook University Geodynamics Research Center Ehime University

Ultrasonic interferometry was utilized in conjunction with synchrotron-based X-ray diffraction and X-radiographic imaging to determine the compressional and shear wave velocities and unlt-cdl volumes of pyrite （FeS2） at room temperature and pressures up to 9.6 GPa. Fitting all of the experimental volume and velocity data to third-order finite-strain equations yielded the adiabatic zero-pressure bulk and shear moduli and their first pressure derivatives： Ks0=138.9（7） GPa, Go=U2.3（3） GPa, （δKS0/δP）T=KS0＇=6.0（1）, （δG0/δP）T=G0＇=3.0（〈1）, where the numbers in parentheses represent the 1δ uncertainty in the last significant digit. These results are in good agreement with several previous static compression studies on this material but differ quite strongly from the results obtained via first principles calculations. This study presents the first direct measurement of the bulk shear properties of this material.

关键词： mineral physics ultrasonic interferometry high pressure iron sulfide elastic property equation of state.