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A new type of cell related to organ movement for selfing in plants

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National Science Review 2023年第9期10卷 190-203页

作者： Yin-Zheng Wang Yan-Xiang Lin Qi Liu Jing Liu spencer c.h.barrett State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of Sciences china National Botanical Garden college of Life Sciences University of Chinese Academy of Sciences college of Pharmacy Fujian University of Traditional Chinese Medicine Department of Ecology and Evolutionary Biology University of Toronto

Many plants employ osmotic and hydrostatic pressure to generate movement for survival,but little is known about the cellular mechanisms ***,we report a new cell type in angiosperms termed ’contractile cells’ in the stigmas of the flowering plant chirita pumila with a much-expanded rough endoplasmic reticulum(RER).cryo-scanning electron microscopy and transmission electron microscopy analyses revealed that the RER is continuously distributed throughout the entirety of cells,confirmed by endoplasmic reticulum(ER)-specific fluorescent labeling,and is distinct from the common feature of plant *** RER is water-sensitive and extremely elongated with water *** show that the contractile cells drive circadian stigma closing-bending movements in response to day-to-night moisture ***-seq analyses demonstrated that contractile cells have distinct molecular ***,multiple microstructural changes in stigma movements convert an anti-selfing structure into a device promoting selfing—a unique cellular mechanism of reproductive adaptation for uncertain pollination environments.

关键词： stigma movement rough endoplasmic reticulum contractile cells circadian moisture changes reproductive transition

Evolutionary Genomics of Plant Gametophytic Selection

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Plant communications 2020年第6期1卷 18-33页

作者： Felix E.G.Beaudry Joanna L.Rifkin spencer c.h.barrett Stephen I.Wright Department of Ecology and Evolutionary Biology The University of Toronto25 Willcocks StreetTorontoON M5S 3B2Canada These authors contributed equally to this article

It has long been recognized that natural selection during the haploid gametophytic phase of the plant life cycle may have widespread importance for rates of evolution and the maintenance of genetic *** theoretical advances have further highlighted the significance of gametophytic selection for diverse evolutionary *** approaches offer exciting opportunities to address key questions about the extent and effects of gametophytic selection on plant evolution and ***,we review the progress and prospects for integrating functional and evolutionary genomics to test theoretical predictions,and to examine the importance of gametophytic selection on genetic diversity and rates of *** is growing evidence that selection during the gametophyte phase of the plant life cycle has important effects on both gene and genome evolution and is likely to have important pleiotropic effects on the *** discuss the opportunities to integrate comparative population genomics,genome-wide association studies,and experimental approaches to further distinguish how differential selection in the two phases of the plant life cycle contributes to genetic diversity and adaptive evolution.

关键词： gametophyte pollen ovule evolution genomics selection

Sex-specific plasticity of reproductive allocation in response to water depth in a clonal, dioecious macrophyte

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Sex-specific plasticity of reproductive allocation in respon...

characterization of 24 microsatellite markers in Primula chungensis(Primulaceae),a distylous-homostylous species,using MiSeq sequencing

中国植物学会第十六次全国会员代表大会暨85周年学术年会

作者： Lei Li spencer c.h.barrett Jiakuan chen center for Watershed Ecology Institute of Life Science and School of Life SciencesNanchang University Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of EducationNanchang University Department of Ecology and Evolutionary Biology University of Toronto The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Institute of Biodiversity ScienceFudan University

Sex-specific differences in reproduction investment contribute to sexual dimorphism in dioecious *** environmental gradients,males and females may plastically adjust reproductive allocation differently because of contrasting reproductive *** dioecious macrophytes,variation in water depth is likely to influence reproductive allocation but has not been investigated in ***,we experimentally examined in aquatic mesocosms plasticity in allocation using Vallisneria spinulosa,a dioecious,clonal,submerged macrophyte to investigate whether sexual dimorphism in reproductive allocation and vegetative growth change in response to varying water depths（50,100 and 150 cm）.Females invested a higher fraction of resources to sexual reproduction than males across all water depths and decreased proportional allocation to sexual structures in shallow and deep water compared to intermediate water *** contrast,males maintained similar sexual allocation across all water depth *** displayed larger vegetative size than males,despite greater sexual investment,but decreased vegetative biomass more than males in shallow or deep *** sexes invested similarly in clonal propagation by tubers at all water depths but a trade-off with sexual reproduction was only evident in *** results suggest that females of *** have mechanisms enabling compensation of the costs of sexual reproduction in heterogeneous *** to males,females expressed greater plasticity in biomass allocated to sexual reproduction and vegetative growth in response to water depth *** variation in underwater light availability probably elicited the sex-specific allocation strategies we observed in ***.

关键词： cost of reproduction dioecy reproductive effort sexual dimorphism submerged aquatic Vallisneria spinulosa water depth

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植物分类与资源学报 2016年第2期38卷 110-113页

作者： Wei Zhou haidong Li Zhikun Wu spencer c.h.barrett Dezhu Li hong Wang Plant Germplasm and Genomics center Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of Sciences Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences Kunming college of Life Sciences University of Chinese Academy of Sciences Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of Sciences Department of Ecology and Evolutionary Biology University of Toronto

Primula chungensis is a species with considerable floral and mating-system variation,including distylous(outcrossing),homostylous(selfing) and mixed populations that contain both outcrossing and selfing *** isolated 24 microsatellite markers from *** using Illumina Mi Seq *** and genetic diversity were then measured based on a sample of 24 individuals from a natural population in southern *** loci were polymorphic with the number of alleles per locus ranging from 2 to *** observed and expected heterozygosity ranged from 0 to 1 and 0.219 to 0.708,*** microsatellite markers we have identified will serve as valuable tools for the investigation of the population genetic structure and phylogeography of *** and will inform models of the evolutionary history of mating systems in the species.

关键词： Distyly homostyly Microsatellites Polymorphism Primula chungensis

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A continental back-arc setting for the Namaqua belt:Evidence from the Kakamas Domain

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Geoscience Frontiers 2022年第4期13卷 193-221页

作者： P.h.Macey R.J.Thomas A.F.M.Kisters J.F.A.Diener M.Angombe S.Doggart c.A.Groenewald c.W.Lambert J.A.Miller h.Minnaar h.Smith h.F.G.Moen E.Muvangua A.Nguno G.Shifotoka J.Indongo D.Frei c.spencer P.le Roux R.A.Armstrong c.Tinguely council for Geoscience P.O.Box 572BellvilleSouth Africa Department of Geology University of StellenboschSouth Africa Department of Geological Sciences University of Cape TownSouth Africa Geological Survey of Namibia WindhoekNamibia Department of Geology University of Free StateSouth Africa Department of Earth Sciences University of the Western CapeSouth Africa The Institute of Geoscience Research Dept.Applied GeologyCurtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK RSES Australian NationalUniversityCanberraACTAustralia

A study of the NW Kakamas Domain in South Africa/Namibia provides a new,unified lithostratigraphy and evolutionary history applicable to the whole Namaqua *** Mesoproterozoic history ranges from~1350 Ma to 960 Ma,but isotopic evidence suggests it was built upon pre-existing Paleoproterozoic continental crust that extended west from the Archaean *** eastern Namaqualand,early rift-related magmatism and sedimentation at~1350 Ma occurred in a confined ocean *** tectonic reversal and subduction at~1290–1240 Ma led to establishment of the Areachap,Konkiep and Kaaien *** the Kakamas Domain,widespread deposition of pelitic sediments occurred at~1220 Ma(Narries Group).These contain detrital zircons derived from proximal crust with ages between~2020 Ma and 1800 Ma(western Palaeoproterozoic domains)and 1350–1240 Ma(eastern early Namaqua domains),suggesting pre-sedimentation *** pelites underwent granulite grade metamorphism at~1210 Ma(peak conditions:4.5–6 kbar and 770–850°c),associated with voluminous,predominantly S-type granitoid orthogneisses between~1210 Ma and 1190 Ma(Eendoorn and ham River Suites)and low-angle ductile(D_(2))deformation which continued until~1110 Ma,interspersed with periods of *** enduring P-T regime is inconsistent with the expected crustal over-thickening associated with the generally-accepted collision-accretion Namaqualand ***,we propose the Namaqua Sector is a‘hot orogen’developed in a wide continental back-arc with subduction west of the present-day *** observed high geotherm resulted from thinned back-arc lithosphere accompanied by an influx of mantle-derived *** D_(2)deformation resulted from"bottom-driven"tectonics and viscous drag within the crust by convective flow in the underlying asthenospheric *** extended tectonothermal regime ceased at~1110 Ma when SW-directed thrusting stacked the Namaqua Domains into their current positions,constrained in

关键词： Kakamas Namaqua Geodynamics Geochronology hot orogeny Mesoproterozoic

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Formidable females redux:male social integration into female networks and the value of dynamic multilayer networks

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current Zoology 2021年第1期67卷 49-57页

作者： Tyler R.BONNELL chloéVILETTE christopher YOUNG Stephanus Peter hENZI ouise barrett Department of Psychology University of Lethbridge4401 University DriveLethbridgeT1K 3M4Canada Applied Behavioural Ecology and Ecosystems Research Unit University of South AfricaFloridaGautengSouth Africa Endocrine Research Laboratory Mammal Research InstituteFaculty of Natural and Agricultural ScienceUniversity of PretoriaPretoriaSouth Africa

The development of multilayer network techniques is a boon for researchers who wish to understand how different interaction layers might influence each other,and how these in turn might influence group ***,we investigate how integration between male and female grooming and aggression interaction networks influences male power trajectories in vervet monkeys chlorocebus *** previous analyses of this phenomenon used a monolayer approach,and our aim here is to extend these analyses using a dynamic multilayer *** do so,we constructed a temporal series of male and female interaction *** then used a multivariate multilevel autoregression model to compare cross-lagged associations between a male's centrality in the female grooming layer and changes in male Elo *** results confirmed our original findings:changes in male centrality within the female grooming network were weakly but positively tied to changes in their Elo ***,the multilayer network approach offered additional insights into this social process,identifying how changes in a male's centrality cascade through the other network *** dynamic view indicates that the changes in Elo ratings are likely to be short-lived,but that male centrality within the female network had a much stronger impact throughout the multilayer network as a whole,especially on reducing intermale aggression(i.e.,aggression directed by males toward other males).We suggest that multilayer social network approaches can take advantage of increased amounts of social data that are more commonly collected these days,using a variety of *** data are inherently multilevel and multilayered,and thus offer the ability to quantify more precisely the dynamics of animal social behaviors.

关键词： multilayer networks multilevel multivariate autoregressive model primate social dynamics social networks sociality time-aggregated networks vervet monkeys

hardening Effects in Superhard Transition-Metal Borides

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Accounts of Materials Research 2022年第1期3卷 100-109页

作者： Lisa E.Pangilinan Shanlin hu spencer G.hamilton Sarah h.Tolbert Richard B.Kaner Department of chemistry and Biochemistry University of CaliforniaLos Angeles(UCLA)Los AngelesCalifornia 90095United States Department of chemistry and Biochemistry Department of Materials Science and Engineeringand California NanoSystems Institute(CNSI)University of CaliforniaLos Angeles(UCLA)Los AngelesCalifornia 90095United States

cONSPEcTUS:Mechanical hardness is a physical property used to gauge the applications of materials in the manufacturing and machining *** of their high hardness and wear resistance,superhard materials(Vickers hardness,hv≥40 GPa)are commonly used as cutting tools and *** diamond is the hardest known material used for industrial applications,its synthesis requires both high pressure and high *** in the field of superhard materials research has led to the search for alternatives with high hardness and thermal stability at low *** discovery of novel ultraincompressible,superhard materials has largely developed through trial and error along two *** one approach,researchers combine light elements,such as boron,carbon,nitrogen,and oxygen,often at high pressure,to replicate the highly directional,dense,covalent bonds of *** the second approach,these light elements(B,c,N,and O)are combined with highly incompressible,electron-rich transition metals to form dense covalently bonded networks at ambient pressure.

关键词： Transition boron gauge

Spectral/hp element methods:Recent developments, applications, and perspectives

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Journal of hydrodynamics 2018年第1期30卷 1-22页

作者： hui Xu chris D.cantwell carlos Monteserin claes Eskilsson Allan P.Engsig-Karup spencer J.Sherwin Department of Aeronautics Imperial College London Department of Applied Mathematics and computer Science Technical University of Denmark Department of civil Engineering Aalborg University Division Safety and Transport Research Institutes of Sweden (RISE) center for Energy Resources Engineering (cERE) Technical University of Denmark

The spectral/hp element method combines the geometric flexibility of the classical h-type finite element technique with the desirable numerical properties of spectral methods, employing high-degree piecewise polynomial basis functions on coarse finite element-type meshes. The spatial approximation is based upon orthogonal polynomials, such as Legendre or chebychev polynomials,modified to accommodate a c~0-continuous expansion. computationally and theoretically, by increasing the polynomial order p,high-precision solutions and fast convergence can be obtained and, in particular, under certain regularity assumptions an exponential reduction in approximation error between numerical and exact solutions can be achieved. This method has now been applied in many simulation studies of both fundamental and practical engineering flows. This paper briefly describes the formulation of the spectral/hp element method and provides an overview of its application to computational fluid dynamics. In particular, it focuses on the use of the spectral/hp element method in transitional flows and ocean engineering. Finally, some of the major challenges to be overcome in order to use the spectral/hp element method in more complex science and engineering applications are discussed.

关键词： high-precision spectral/hp elements continuous Galerkin method discontinuous Galerkin method implicit large eddy simulation

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