检索结果-南通市图书馆

Opportunism and the resilience of barnacles (Cirripedia: Thoracica) to environmental change

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Integrative Zoology 2012年第2期7卷 137-146页

作者： john s.BUCKERIDGE Earth and Oceanic systems RMIT UniversityMelbourneAustralia

Cirripede-like organisms have their origins in the Palaeozoic,but until the Cainozoic,were represented primarily by pedunculated forms,such as the *** barnacles(Balanomorpha)are first recorded after the Cretaceous-Tertiary extinction *** the late Palaeogene,rapid radiation of cirripedes resulted in sufficient diversification for them to occupy most marine *** they survived both the Palaeocene-Eocene Thermal Maximum and the Pleistocene glaciation is testament to their ability to rapidly adapt to *** wide habitat distribution of balanomorphs in particular is unparalleled;they are known from the upper littoral(Chthamalus)to depths of 3600 m(Tetrachaelasma)and within this attached to rock,wood and miscellaneous flotsam,plus in symbiosis or commensalism with larger marine ***’s(1854)view of the Tertiary as the age of barnacles is reflected in this diversity,distribution and *** cirripedes are,nonetheless,at risk,from rapid habitat change,competition,pollution and,especially in light of their sessile habit,from *** paper assesses the viability of a number of cirripedes and concludes that the Lepadiformes,scalpelliformes and Balanomorpha are the most resilient,and will most quickly adapt to occupy new niches when opportunities arise.

关键词： adaptation Cirripedia distribution environmental change

some biological consequences of environmental change:A study using barnacles(Cirripedia:Balanomorpha)and gum trees(Angiospermae:Myrtaceae)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Integrative Zoology 2010年第2期5卷 122-131页

作者： john s.BUCKERIDGE Earth and Oceanic systems RMIT UniversityMelbourneAustralia

Uniformitarianism permits understanding of the past on the basis of the present,and modeling the future through consideration of the fossil *** present paper addresses the impact environmental(climatic)change has had on acorn barnacles and eucalyptus *** barnacles(Balanomorpha)are first recorded after the K/T massextinction *** the Paleogene,rapid radiation resulted in their occupying most marine *** balanomorphs survived both the Paleocene–Eocene thermal maximum and the Pleistocene glaciation is testament to their ability to adapt to opportunities;they are known from the littoral(Chamaesipho)to depths of 3600 m(Tetrachaelasma)and within this from diverse substrates:rock,wood and miscellaneous flotsam,plus in symbiosis or commensalism with most larger marine ***’s(1854)view of the late Tertiary as the age of barnacles is reflected in their diversity,distribution and *** are contrasted with the Australian Myrtaceae:plants ranging from woody shrubs to tall *** most significant is Eucalyptus sensu lato,which typifies Australia’s flora,and is characterized by aromatic leaves that produce *** has evolved strategies that result in its domination of Australian open woodlands:these include production of highly flammable eucalyptol oil(with a flashpoint of 49℃)and an unprecedented ability to regenerate following forest *** trees and barnacles first appear in the Paleogene,their earliest records are Australasian,and they both demonstrate extraordinary resilience when environmental conditions are optimal.

关键词： adaption barnacles environmental change eucalypts evolution

Detrital zircon U-Pb geochronology and geochemistry of the Riachuelos and Palma sola beach sediments,Veracruz state,Gulf of Mexico:a new insight on palaeoenvironment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2020年第4期9卷 495-521页

作者： john s.Armstrong-Altrin Unidad de Procesos Oceánicos y Costeros Instituto de Ciencias del Mar y LimnologíaUniversidad Nacional Autónoma de MéxicoCiudad UniversitariaCiudad de México 04510México

Zircons are abundant in the beach *** this study,surface microtexture,mineralogy,bulk sediment geochemistry,trace element composition and U−Pb isotopic geochronology of detrital zircons collected from the Riachuelos and Palma sola beach areas,southwestern Gulf of Mexico were performed to infer the sediment provenance and *** zircon microtexture was categorized as mechanically-and/or chemically-induced *** weathering index values for the Riachuelos(~72−77)and Palma sola(~71−74)beach sediments indicated moderate weathering of both of the two source *** major and trace element data of bulk sediments suggested passive margin settings for the two *** trace elemental ratios and chondrite-normalized rare earth element(REE)patterns of bulk sediments revealed that the sediments were likely sourced by felsic and intermediate igneous *** the zircon Th/U ratios(mostly more than 0.2)and zircon REE patterns(with negative Eu and positive Ce anomalies)suggested a magmatic origin for both of the beach sediments from these two *** distinct zircon age peaks respectively belonging to the Paleozoic and the Cenozoic were identified both in the Riachuelos and Palma sola beach *** geochronology comparison research between the Riachuelos−Palma sola beach sediments and potential source areas in sW Gulf of Mexico revealed that the source terrane supplied the Paleozoic zircons of this study was identified as the Mesa Central Province(MCP),and the Cenozoic zircons were transported from the nearby Eastern Alkaline Province(EAP).Moreover,although the Precambrian zircons were very few in the studied sediments,their geochronology and geochemistry results still could infer that they were contributed by the source terranes of Grenvillian igneous suites in the Oaxaca and the Chiapas Massif Complexes.

关键词： Detrital zircon Beach sediment U-Pb dating Zircon grain morphology Microtexture Mineralogy Geochemistry Geochronology Gulf of Mexico

Interaction between gut microbiota and COVID-19 and its vaccines

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2022年第40期28卷 5801-5806页

作者： john s M Leung Cardiothoracic Unit St.Paul’s HospitalHong KongChina

The whole world has been continuously afflicted by the coronavirus disease 2019(COVID-19)pandemic for the past 3 *** countries have tried many methods to control this virus infection with varying successes and *** gut microbiota is a biosystem spanning the entire length of the digestive tract and playing important roles in health and *** is much affected by *** return it also substantially impacts *** particular,the gut microbiota has established a bidirectional interaction with the COVID-19 vaccines,enhancing or reducing vaccine efficacy by virtue of its varying ***,COVID-19 vaccines also make a substantial impact on the gut microbiota,reducing its overall population and *** is hoped that by exploring and harnessing this bidirectional interaction we may break new ground and develop new methods to prevent and treat this formidable virus infection.

关键词： Gut microbiota COVID-19 vaccines Vaccine interactions Gut microbiota alterations

On ethics,the pursuit of knowledge,truth and status in the hallowed halls of academe

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Integrative Zoology 2013年第3期8卷 223-231页

作者： john s.BUCKERIDGE Rob WATTs Earth&Oceanic systems Group RMIT UniversityMelbourneVictoriaAustralia

Advancement in academe is largely on the basis of research output;that is,refereed journal *** paper first explores pressures on academics,especially emerging researchers,when English is not a first *** assess why,when faculty members rush to improve their station that they may elect to circumvent ethical protocols to accelerate their promotion and *** resulting unethical behavior includes plagiarism and forms of duplication such as *** is then given to the wider implications of both plagiarism and the theft of intellectual property,and the role these have played in the development of individuals,the university and society.

关键词： ethics plagiarism promotion publication social evolution

A FAsT LAGRANGIAN sIMULATION METHOD FOR FLOW ANALYsIs AND RUNNER DEsIGN IN PELTON TURBINEs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2012年第6期24卷 930-941页

作者： ANAGNOsTOPOULOs john s. PAPANTONIs Dimitris E. school of Mechanical Engineering National Technical University of Athens

In the present work, an alternative numerical methodology is developed for a fast and effective simulation and analysis of the complex flow and energy conversion in Pelton impulse hydro turbines. The algorithm is based on the Lagrangian approach and the unsteady free-surface flow during the jet-bucket interaction is simulated by tracking the trajectories of representative fluid particles at very low computer cost. Modern regression tools are implemented in a new parameterization technique of the inner bucket surface. Key-feature of the model is the introduction of additional terms into the particle motion equations to account for various hydraulic losses and the flow spreading, which are regulated and evaluated with the aid of experimental data in a Laboratory Pelton turbine. The model is applied to study the jet-runner interaction in various operation conditions and then to perform numerical design optimization of the bucket shape, using a stochastic optimizer based on evolutionary algorithms. The obtained optimum runner attains remarkably higher hydraulic efficiency in the entire load range. Finally, a new small Pelton turbine （150 kW） is designed, manufactured and tested in the Laboratory, and its performance and efficiency verify the model predictions.

关键词： Pelton turbine hydraulic efficiency Lagrangian simulation bucket shape parameterization numerical design optimization

Human development across the lifespan Updated 5th ed.

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The“Tears of the Virgin”at Lakes Entrance,southeast Australia were made by the intertidal barnacle Chthamalus antennatus(Cirripedia:Thoracica)and cyanobacteria

2004年

作者： john s. Dacey john F. Travers.

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Integrative Zoology 2017年第3期12卷 228-236页

作者： john s.BUCKERIDGE William A.NEWMAN Earth&Oceanic systems Group RMIT UniversityMelbourneVictoriaAustralia scripps Institution of Oceanography La JollaCaliforniaUSA

Curious eroded depressions,most resembling an eye shedding an elongate tear,are found in gently sloping,intertidal,carbonate-rich arenite outcropping on the sea coast near Lakes Entrance,Victoria,southeast *** depressions,known locally as“Tears of the Virgin,”are evidently formed by multiple generations of a barnacle,Chthamalus antennatus Darwin,1854 in association with *** the round part of a depression offers the barnacle a modicum of protection from impacts during high tides,it is also partially inhabited by cyanobacteria,which extend into and tend to fill the elongate *** such,this appears to be the first case of mutualism between a higher invertebrate and cyanobacteria,with the cyanobacteria reducing the barnacle’s risk of desiccation while receiving metabolic wastes from it during low *** is also the first record of a balanomorph barnacle eroding calcareous arenite beneath its shell,the net effect of which would be expected to reduce its adhesion to the ***,the siliceous residue,resulting from the barnacle’s dissolution of the more than 80%of the calcite-rich sedimentary rock,is sequestered in delicate folds on the inside of the shell wall as it grows.A brief review of cirripedes capable of excavation includes the first photographic documentation of excavation of a mollusc shell by a verrucomorph.

关键词： burrowing barnacles Chthamalus antennatus Cirripedia cyanobacteria mutualism

CR deformations for rational homogeneous surface singularities

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

science China Mathematics 2005年第Z1期48卷 74-85页

作者： john s.Bland Department of Mathematics University of Toronto TorontoM5S 3G3Canada

In this paper, we will present a CR-construction of the versal deformations of the singularities Vn (～- )C2/Zn, n ∈ {2, 3, 4,…} defined by the immersions of C2 into Cn+1Xn: (z,w) → (zn,zn-1w,…,zwn-1,wn).

关键词： CR deformation, obstruction.