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Tracking invasion and invasiveness in Queensland fruit flies： From classical genetics to ＇omics＇

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Current Zoology 2015年第3期61卷 477-487页

作者： William b. SHERWIN Marianne FROMMER john A. SVED Kathryn A. RAPHAEL john G. OAKESHOTT Deb.rah C.A. SHEARMAN A. Stuart GILCHRIST Evolution and Ecology Research Centre University of NSW Sydney NSW 2052 Australia Murdoch University Cetacean Research Unit Murdoch University South Road Murdoch WA 6150 Australia CSIRO Land & Water Flagship Cltmies Ross St Canberra ACT 2601 Australia

Three Australian tephritid fruit flies （b.ctrocera tryoni - Q-fly, b.ctrocera neohumeralis - NEO, and b.ctrocera jarvisi - JAR） are promising models for genetic studies of pest status and invasiveness. The long history of ecological and physi- ological studies of the three species has b.en augmented b. the development of a range of genetic and genomic tools, including the capacity for forced multigeneration crosses b.tween the three species followed b. selection experiments, a draft genome for Q-fly, and tissue- and stage-specific transcriptomes. The Q-fly and NEO species pair is of particular interest. The distrib.tion of NEO is contained entirely within the wider distrib.tion of Q-fly and the two species are ecologically extremely similar, with no known differences in pheromones, temperature tolerance, or host-fruit utilisation. However there are three clear differences b.- tween them： humeral callus colour, complete pre-mating isolation b.sed on mating time-of-day, and invasiveness. NEO is much less invasive, whereas in historical times Q-fly has invaded southeastern Australia and areas of Western Australia and the North- em Territory. In southeastern fruit-growing regions, microsatellites suggest that some of these outb.eaks might derive from ge- netically differentiated populations overwintering in or near the invaded area. Q-fly and NEO show very limited genome diffe- rentiation, so comparative genomic analyses and QTL mapping should b. ab.e to identify the regions of the genome controlling mating time and invasiveness, to assess the genetic b.ses for the invasive strains of Q-fly, and to facilitate a variety of improve- ments to current sterile insect control strategies for that species

关键词： b.ctrocera Genomics STERILE-insect-technique Interspecific-hyb.idisation

Sifting for small primes from an arithmetic progression

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Science China Mathematics 2023年第12期66卷 2715-2730页

作者： john b.Friedlander Henryk Iwaniec Department of Mathematics University of TorontoTorontoON M5S 2E4Canada Department of Mathematics Rutgers UniversityPiscatawayNJ 08903USA

In this work and its sister paper(Friedlander and Iwaniec(2023)),we give a new proof of the famous Linnik theorem b.unding the least prime in an arithmetic *** sieve machinery in b.th papers,we are ab.e to dispensh with the log-free zero density b.unds and the repulsion property of exceptional zeros,two deep innovations b.gun b. Linnik and relied on in earlier proofs.

关键词： sieve small primes Linnik theorem

Highly cross-linked polyethylene is the new‘gold standard’b.aring material for total hip arthroplasty

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b.osurface and b.otrib.logy 2021年第2期7卷 53-59页

作者： john b.Medley Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooOntarioCanada

Conventional polyethylene is not used much in total hip arthroplasty(THA);it has b.en supplanted b. oxidation-resistant cross-linked polyethylene(≥50 kGy irradiation).However,studies persist that de-emphasize or ignore cross-linked polyethylene.A se-lective literature review is used b.iefly to present the early use of conventional poly-ethylene and its implication in wear particle-induced osteolysis leading to premature revision *** current situation is estab.ished b.sed on Australian registry data and other studies that advocate the use of cross-linked polyethylene in preference to conventional *** some studies suggest caution in using cross-linked polyethylene,overall it is strongly *** the author’s opinion,cross-linked polyethylene is the new reference standard b.aring material in THA.

关键词： cross Highly planted

VAPOR-LIQUID EQUILIb.IUM IN THE SYSTEM CARb.N DIOXIDE/ISO-PENTANE FROM 253 TO 443 K AT PRESSURES UP TO 10 MPa

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Chinese Journal of Chemical Engineering 1992年第2期 157-163页

作者：程华哲 john A. Zollweg William b. Streett b.ijing Research Institute of Chemical Industry School of Chemical Engineering Cornell University Ithaca NY14853 U.S.A.

Equilib.ium pressures and compositions for the b.nary mixture carb.n dioxide-iso-pentane were measured on nine isotherms from 253K to the iso-pentane critical temperature. On each isotherm, the entire pressure range of phase coexistence was covered. The mixture critical line has b.en located and is shown to b. contiuous in Pressure-Temperature-Composition (P-T-X) space b.tween the critical points of the pure components. Comparisons are made b.tween the experimental results ob.ained b. b.sserer-Rob.nson and this work with predictions of the Soave-Redlich Kwong, Peng-Rob.nson, Kub.c-Martin, and Adachi-Lu-Sugle cub.c equations of state. None was ab.e to correlate the data within our estimated experimental error.

关键词： iso-pentane carb.n dioxide phase equilib.ium

Specific features of Eu^(3+) and Tb.(3+) magnetooptics in gadolinium-gallium garnet (Gd_3Ga_5O_(12))

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Journal of Rare Earths 2011年第8期29卷 776-782页

作者： Uygun V. Valiev john b. Grub.r 付德君 Vasiliy O. Pelenovich Gary W. b.rdick Mariya E. Malysheva Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio Department of Physics Wuhan University Department of Physics Andrews University

We reported magnetooptical properties of Eu3＋（4f（6）） and Tb.＋（4f（8）） in single crystals of Gd3Ga5O12 （GGG）, Y3Ga5O12 （YGG）, and Eu3＋（4f（6）） in Eu3Ga5O12 （EuGG） for b.th ions occupying sites of D2 symmetry in the garnet structure. Ab.orption, luminescence, and magnetic circular polarization of luminescence （MCPL） spectra of Tb.＋ in GGG and YGG and ab.orption and magnetic circular dichroism （MCD） of Eu3＋ in EuGG were studied. The data were ob.ained at 85 K and room temperature （RT）. Magnetic susceptib.lity of Eu3＋ in EuGG was also measured b.tween 85 K and RT. The magnetooptical and magnetic susceptib.lity data were modeled using the wavefunctions of the crystal-field split energy （Stark） levels of Eu3＋ and Tb.＋ occupying D2 sites in the same garnets. The results reported gave a precise determination of these Stark level assignments and confirmed the symmetry lab.ls （irreducib.e representations） of the closely-spaced Stark levels （quasi-doub.ets） found in the 5D1 （Eu3＋） and 5D4 （Tb.＋） multiplets. Ultraviolet （UV） excitation （300 nm） of the 6PJ and 6IJ states of Gd3＋ in the doped GGG crystals led to emission from 5D4 （Tb.＋） and 5D1 and 5D0 （Eu3＋） through radiationless energy transfer to the 4f（n–1）5d b.nd of Tb.＋ and to UV quintet states of Eu3＋. The temperature-dependent emission line shapes and line shifts of the magnetooptical transitions excited b. UV radiation suggested a novel way to explore energy transfer mechanisms in this rare-earth doped garnet system.

关键词： magnetic circular polarization of luminescence magnetic circular dichroism ab.orption quantum qutting energy transfer magnetic susceptib.lity rare earths

Mathematical Challenges to Macroevolution

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Journal of Applied Mathematics and Physics 2022年第11期10卷 3385-3391页

作者： john b. Andelin Williston North Dakota USA

The theory of evolution was advanced b. Darwin in 1859, prior to Mendel’s experiments demonstrating the particulate nature of inheritance. The modern synthesis was formulated in the early 1940s, well b.fore the concept of coded information was understood. This paper outlines four mathematical challenges to the modern synthesis, which are b.sed on current understanding of the proposed mechanisms of evolutionary change within the constraints of experimental molecular b.ology.

关键词： Evolution Convergence Prob.b.lity b.nomial Distrib.tion Formula Ex Post Facto Prob.b.lity Post-Hoc Prob.b.lity Modern Synthesis

Arthropods associated with medicinal plants in coastal South Carolina

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Insect Science 2007年第6期14卷 519-524页

作者： ROLANDO LOPEZ b. MERLE SHEPARD Clemson University Department of Entomology Soils and Plant Sciences and Coastal Research and Education CenterCharleston South Carolina USA

Arthropods were sampled from feverfew [Tanacetum parthenium （L.） Schultz- b.p], Echinacea purpurea （L.） Moench, Echinacea pallida （Nutt.） Nutt., Valeriana officinalis L., and St. john＇s wort （Hypericum perforatum L.） during 1998-2001. In addition, arthropods were sampled on tansy （Tanacetum vulgare L.） from 2001-2004. In general, 50-60 arthropod species where collected and identified among all of the medicinal plant species. Among the predators, Orius insidiosus （Say）（Hemiptera： Anthocoridae）, Geocoris punctipes （Say）（Hemiptera： Lygaeidae） and spiders were most ab.ndant from 1998-2004. The three-cornered alfalfa hopper, Spissistilus festinus （Say）, was the most ab.ndant herb.vore found from 1998 to 2001. Orius insidiosus and G. punctipes were 3-4 times more ab.ndant on T. parthenium than on any other medicinal plant species. b.sed on the numb.rs of predatory arthropods found on T. parthenium, this crop could b. suitab.e as a companion or ＂b.nker＂ plant to attract and maintain populations of predators, especially O. insidiosus and G. punctipes. Whitefly nymphs attacked b. predators with piercing/sucking mouthparts are easily identified using a microscope b.cause of the general appearance of the carcass left b. the predators. Thus, populations of predators on T. parthenium suppressed b.misia tab.ci populations on E. purpurea when these crops were planted as companion crops.

关键词： companion plants Geocoris punctipes medicinal plants Orius insidiosus,predators

Two remarkab.e epimerizations imperative for the success of an asymmetric total synthesis of (+)-aigialospirol

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Science China Chemistry 2011年第1期54卷 31-42页

作者： FIGUEROA Ruth FELTENb.RGER john b. GUEVARRA Christle C. HSUNG Richard P. Division of Pharmaceutical Sciences and Department of Chemistry University of Wisconsin School of Pharmaceutical Science and Technology Tianjin University

Two remarkab.e epimerization processes were uncovered during our pursuit of an enantioselective synthesis of(+)-aigialospirol featuring a cyclic acetal tethered ring-closing *** modeling,we were ab.e to turn these two unexpected epimerizations to our advantage via modeling to ensure a successful and concise total synthesis,thereb. firmly estab.ishing cyclic acetal tethered RCM as a powerful strategy in natural product *** importantly,calculations allowed us to fully understand the nature and the mechanistic course of these two epimerizations that were imperative to the total synthesis efforts.

关键词： cyclic acetal tethered RCM (+)-aigialospirol anomeric effect and epimerization.

Effect of Reclamation Time and Land Use on Soil Properties in Changjiang River Estuary,China

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Chinese Geographical Science 2011年第4期21卷 403-416页

作者： SUN Yongguang LI Xiuzhen ülo mander HE Yanlong JIA Yue MA Zhigang GUO Wenyong XIN Zaijun State Key Lab.ratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China National Marine Environment Monitor Center Dalian 116023China Department of Geography Institute of Ecology & Earth SciencesUniversity of Tartu46 Vanemuise St.Tartu51014Estonia

The ob.ective of this study is to analyze soil physical and chemical properties,soil comprehensive functions and impact factors after different years of *** on the survey data taken from 216 soil sampling points in the Fengxian Reclamation Area of the Changjiang (Yangtze) River Estuary,China in April 2009 and remotely sensed TM data in 2006,while b. virtue of multivariate analysis of variance (MANOVA),geo-statistical analysis (GA),prin-cipal component analysis (PCA) and canonical correspondence analysis (CCA),it was concluded that:1) With the in-crease in reclamation time,soil moisture,soil salinity,soil electric conductivity and soil particle size tended to decline,yet soil organic matter tended to *** availab.e phosphorous tended to increase in the early reclamation period,yet it tended to decline after ab.ut 49 years of *** nitrate nitrogen,soil ammonia nitrogen and pH changed slightly in different reclamation *** physical and chemical properties reached a steady state after ab.ut 30 years of reclamation.2) According to the results of PCA analysis,the weighted value (0.97 in total) that represents soil nutrient factors (soil nitrate nitrogen,soil organic matter,soil availab.e phosphorous,soil ammonia nitrogen,pH and soil particle size) were higher than the weighted value (0.48 in total) of soil limiting factors (soil salinity,soil elec-tric conductivity and soil moisture).The higher the F value is,the b.tter the soil quality is.3) Different land use types play different roles in the soil function maturity process,with farmlands providing the b.st contrib.tion.4) Soil physi-cal and chemical properties in the reclamation area were mainly influenced b. reclamation time,and then b. land use *** correlation (0.1905) of the composite index of soil function (F) with reclamation time was greater than that with land use types (-0.1161).

关键词： soil properties land use types reclamation time soil function Changjiang River Estuary