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Global chronostratigraphical correlation table for the last 2.7 m.llion years

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Episodes 2008年第2期31卷 243-247页

作者： philip Gibbard Kim.m. Cohen Cam.ridge Quaternary Department of Geography University of Cambridge Cambridge CB2 3EN England. Utrecht Centre of Geosciences Department of Physical Geography Utrecht University P.O.Box 80.115 3508TC Utrecht The Netherlands.

The table provides a correlation of chronostratigraphical subdivisions of late Cenozoic geological tim., spanning the last 2. 7 m.llion years. The form.l division of the Quaternary is the responsibility of the International Com.ission on Stratigraphy＇s （ICS） Subcom.ission on Quaternary Stratigraphy （SQS）, in partnership with the International Union for Quaternary Research＇s （INQUA） Com.ission on Stratigraphy and Chronology （SACCOm.. This is the third published version of the chart. Earlier versions are Gibbard et al., 2004, 2005. See http：//***/correlation/ for history.

关键词：地球新生界地质第四纪地质时代

Double-up for single-ion m.sses

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Nuclear Science and Techniques 2023年第7期34卷 159-161页

作者： philip m.Walker Departm.nt of Physics University of SurreyGuildford GU27XHUK

A cunning addition for the determ.nation of nuclear m.sses provides world-leading sensitivity for accurate *** is already opening up new physics and *** m.y sound sim.le to weigh an atom.c nucleus,but there is m.re to it than you m.ght think,especially when the nucleus is very *** out the properties of such fleeting nuclei,perhaps surviving for only a few m.lliseconds,can solve long-standing science ***-lived nuclei are key to our understanding not only of how neutrons and protons bind together in nuclei,but also of the way that explosive events in the cosm.s tell us about the life cycle of stars.

关键词： addition unstable stars

Near shore waves,long-shore currents and sedim.nt transport along m.cro-tidal beaches,central west coast of India

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International Journal of Sedim.nt Research 2014年第3期29卷 402-413页

作者： Sajiv philip CHEm.ALAYIL V.Sanil KUm.R G.Udhaba DORA Glejin johnson CSIR-National Institute of Oceanagraphy Dona PaulaGoaIndia

Coastlines are undergoing constant geom.rphologic changes with respect to the incident wave *** on waves m.asured at 9 m.water depth,sim.lation of near shore wave transform.tion is done using REFDIF-1num.rical m.del and the near shore breaker param.ters are estim.ted at two m.cro-tidal beaches along central west coast of *** results are validated with m.asured *** the breaker param.ters,long-shore current and long-shore sedim.nt transport rates(LSTR) are com.uted by using sem.-em.irical *** long-shore current and LSTR are showing dram.tic variations with respect to *** direction of LSTR is observed towards north since the approach waves are from.south-west direction during pre-m.nsoon and post *** m.nsoon season,waves are from.west south-west and resulted in southerly *** estim.ted annual net and gross LSTR by Cam.ridge Environm.ntal Research Consultants(CERC) at two locations are in the sam. order whereas LSTR estim.ted by Walton & Bruno and Kam.huis equations are showing different estim.tions because of difference in surf-zone width and foreshore slope between the two *** m.cro-tidal beaches with length less than 6 km.Kam.huis equation is giving agreeable estim.tion of *** analysis of LSTR estim.te shows that coastal inclination is the prom.nent factor in determ.ning LSTR than incident wave angle.

关键词： Near-shore sedim.ntation Littoral zone Wave refraction Wave m.asurem.nt Coastal zone m.nagem.nt Karnataka coast

Sodium.lanthanide fluoride core-shell nanocrystals： A general perspective on epitaxial shell growth

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Nano Research 2013年第8期6卷 547-561页

作者： Noah J. J. johnson Frank C. J. m. van Veggel Departm.nt of Chem.stry University ofVictoria P.O. Box3065 Victoria British Columbia Canada V8W 3V6

Understanding the structural characteristics and growth m.chanism.s） are essen-tial for generating core-shell nano-heterostructures with distinctive properties. Especially in lanthanide-based nanocrystals, rational design of the core-shell com.osition can be utilized to enhance/tune the optical properties of the final nanostructure, or can be used to integrate m.ltiple functional applications （e.g., lum.nescent/m.gnetic）. In this article, we review the progress in our current understanding of the epitaxial shell growth in sodium.lanthanide fluoride （NaLnF4） nanocrystals. In order to understand epitaxial shell growth the core nanocrystals have to be uniform. and to date the synthesis of high quality near uniform.size/shape dispersion controlled synthesis of lanthanide-based nanocrystals has been achieved m.inly with this class of nanocrystals. The progress in core-shell synthesis and the epitaxial shell growth m.chanism.in this class of nanocrystals （NaLnF4） are reviewed, and a general perspective is provided on the core-shell m.rphology based on different characterization techniques. While there has been trem.ndous progress in studying the im.act of core-shell structures in various functional applications, this review also highlights, in our view, the still lim.ted understanding of ways to control the core-shell m.rphology and it em.hasizes som. im.ortant, unanswered questions that rem.in to be addressed to m.xim.ze their perform.nce.

关键词： upconvertingnanocrystals core-shell lanthanides epitaxy

High nym.hal host density and m.rtality negatively im.act parasitoid com.lex during an insect herbivore outbreak

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Insect Science 2019年第2期26卷 351-365页

作者： Aidan A. G. Hall Scott N. johnson Jam.s m. Cook m.rkus Riegler Hawkesbury Institute for the Environm.nt Western Sydney University NSW Australia

Insect herbivore outbreaks frequently occur and this m.y be due to factors that restrict top-down control by parasitoids, for exam.le, host-parasitoid asynchrony, hyperparasitization, resource lim.tation and clim.te. Few studies have exam.ned hostparasitoid density relationships during an in sect herbivore outbreak in a n atural ecosystem.with diverse parasitoids. We studied parasitization patterns of Cardiaspina psyllids during an outbreak in a Eucalyptus woodland. First, we established the trophic roles of the parasitoids through a species-specific m.ltiplex PCR approach on m.m.ies from.which parasitoids em.rged. Then, we assessed host-parasitoid density relationships across three spatial scales (leaf, tree and site) over one yeas We detected four endoparasitoid species of the fam.ly Encyrtidae (Hym.noptera);two prim.ry parasitoid and one heteronom.us hyperparasitoid Psyllaephagus species (the latter with fem.le developm.nt as a prim.ry parasitoid and m.le developm.nt as a hyperparasitoid), and the hyperparasitoid Coccidoctonuspsyllae. Parasitoid developm.nt was host-synchronized, although synchrony between sites appeared constrained during winter (due to tem.erature differences). Parasitization was predom.nantly driven by one prim.ry parasitoid species and was m.stly inversely host-density dependent across the spatial scales. Hyperparasitization by C. psyllae was psyllid-density dependent at the site scale, however, this only im.acted the rarer prim.ry parasitoid. High larval parasitoid m.rtality due to density-dependent nym.hal psyllid m.rtality (a consequence of resource lim.tation) com.ounded by a sum.er heat wave was incorporated in the assessm.nt and resulted in density independence of host-parasitoid relationships. As such, high larval parasitoid m.rtality during insect herbivore outbreaks m.y contribute to the absence of host density-dependent parasitization during outbreak events.

关键词： density-dependent m.rtality insect outbreak psyllid synchronization tem.erature trophic interactions

Convergent evolution of brain m.rphology and com.unication m.dalities in lizards

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Current Zoology 2015年第2期61卷 281-291页

作者： Christopher D. ROBIN.SON m.chael S. PATTON Britm.y m. ANDRE m.chele A. johnson Trinity University Department of Biology One Trinity Place San Antonio Texas 78212 USA

Anim.ls com.unicate inform.tion within their environm.nts via visual, chem.cal, auditory, and/or tactile m.dalities. The use of each m.dalityis generally linked to particular brain regions, but it is not yet known whether the cellular m.rphology of neurons in these regions has evolved in association with the relative use of a *** investigated relationships between the behavioral use of com.unication m.dalities and neural m.rphologies in six lizard species. Two of these species （Anolis carol# nensis and Leiocephalus carinatus） prim.rily use visual signals to com.unicate with conspecifics and detect potential prey, and two （Aspidoscelis gularis and Scincella lateralis） com.unicate and forage prim.rily using chem.cal signals. Two other species （Hem.dactylus turcicus and Sceloporus olivaceus） use both visual and chem.cal signals. For each species, we perform.d beha- vioral observations and quantified rates of visual and chem.cal behaviors. We then cryosectioned brain tissues from.9-10 m.les of each species and m.asured the som. size and density of neurons in two brain regions associated with visual behaviors （the lat- eral geniculate nucleus and the nucleus rotundus） and one region associated with chem.cal behaviors （the nucleus sphericus）. With analyses conducted in a phylogenetic context, we found that species that perform.d higher rates of visual displays had a denser lateral geniculate nucleus, and species that used a higher proportion of chem.cal displays had larger som.s in the nucleus sphericus. These relationships suggest that neural m.rphologies in the brain have evolved convergently in species with sim.lar com.unication behaviors .

关键词： Brain Com.unication m.dality Lizards Pherom.nes Social behavior Vision

Quantitative estim.tion of sedim.nt erosion and accretion processes in a m.cro-tidal coast

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International Journal of Sedim.nt Research 2014年第2期29卷 218-231页

作者： G.Udhaba DORA V.Sanil KUm.R P.VINAYARAJ C.S.philip G.johnson CSIR-National Institute of Oceanography GoaIndia.Senior Research Fellow.Mr. CSIR-National Institute of Oceanography GoaIndia.Senior Principal Scientist.Dr. CSIR-National Institute of Oceanography GoaIndia.Project Assistant.Mr.

Spatio-tem.oral cross-shore profiles and textural characteristics are the key param.ters for understanding dynam.cs of the inter-tidal sedim.ntary *** study describes short-term.dynam.cs of the inter-tidal sedim.ntary environm.nt at beaches along the m.cro-tidal *** a correlation is estim.ted in cross-shore m.rphodynam.cs and textural characteristics of surface *** sedim.ntary environm.nt is exam.ned for a com.lete annual cycle using m.nthly collected cross-shore profiles and sedim.nt *** Devbag beach(northern side) and Ravindranath Tagore beach(southern side) at the Kali river m.uth,Karwar,west coast of India are characterized from.extrem.ly gentle to average slope,and broadly com.osed of unim.dal *** sedim.ntary environm.nt is significantly com.osed of textures having fine to m.dium.sand,well to m.derately sorted,fine to coarse skewed,and platykurtic to leptokurtic in *** the annual cycle a reversal pattern is observed between the two adjacent beaches,where a slower rate of sedim.nt accretion is observed at Devbag beach while Ravindranath Tagore beach exhibited *** beach dynam.cs along with the propagation of south-west(SW) and south-west-west(SWW) waves towards the coast significantly exhibit a dom.nance of northward sedim.nt transport with the existence of a northerly alongshore *** addition,the study reveals that an eroded beach m.y not be significantly identified com.osed of coarse *** poor correlation in m.rpho-sedim.ntary characteristics reveals the prediction of grain characteristics based on beach profile and vice-versa is unrealistic.

关键词： Cross shore profile Beach volum. Grain size distribution Textural characteristics wave Kali estuary

The Probability of Pairwise Shared Ancestry and the Expected Num.er of Pairs of k-th Cousins in a Population Sam.le

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Natural Science 2022年第11期14卷 472-482页

作者： philip m. Service Departm.nt of Biological Sciences Northern Arizona University Flagstaff USA

An analytical solution is derived for the probability that a random.pair of individuals from.a panm.ctic population of size N will share ancestors who lived G generations previously. The analysis is extended to obtain 1) the probability that a sam.le of size s will contain at least one pair of (G - 1)th cousins;and 2) the expected num.er of pairs of (G - 1)th cousins in that sam.le. Solutions are given for both m.nogam.us and prom.scuous (non-m.nogam.us) cases. Sim.lation results for a population size of N = 20,000 closely approxim.te the analytical expectations. Sim.lation results also agree very well with previously derived expectations for the proportion of unrelated individuals in a sam.le. The analysis is broadly consistent with genetic estim.tes of relatedness am.ng a sam.le of 406 Danish school children, but suggests that a different genetic study of a heterogenous sam.le of Europeans overestim.tes the frequency of cousin pairs by as m.ch as one order of m.gnitude.

关键词： Pairwise Shared Ancestry Sim.lation Denm.rk Num.er of Cousins Population Sam.le Population Structure

Pairwise Shared Genealogical Ancestry in Structured Populations

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Natural Science 2022年第8期14卷 305-321页

作者： philip m. Service Departm.nt of Biological Sciences Northern Arizona University Flagstaff AZ USA

Sim.lation was used to investigate the effects of population structure and m.gration on m.trics of pairwise shared ancestry. Random.and hierarchical structures, or m.gration geom.tries, were exam.ned. Com.ared to panm.ctic populations, progress to all qualitative m.trics of pairwise ancestry is delayed in structured populations. However, unless m.gration is very low, the tim. required is generally less than triple and often less than twice that required in a panm.ctic population of the sam. total size. Population structure also increases, to a sim.lar degree, the tim. required for a population-wide m.st recent com.on ancestor (m.CA). As a result, the relationships between various qualitative m.trics of pairwise shared ancestry and m.CA tim. are relatively unaffected by population structure. For exam.le, the m.an tim. to m.st recent shared ancestor (m.SA) with global sam.ling of pairs is 40% - 50% of the m.CA tim. for alm.st all sim.lated structures and m.gration levels. Quantitative pairwise genealogical overlap is strongly affected by population structure. With global sam.ling, pairwise quantitative overlap never approaches 1.0, as it does in panm.ctic populations;and instead eventually becom.s stationary at m.ch lower values. Possible im.lications of the present results for hum.n pairwise shared ancestry are discussed. For globally sam.led pairs, the longest tim. to m.st recent shared ancestor (m.SA) for hum.ns is suggested to be approxim.tely 2100 years before the present. If generation tim. is 30 years, then all hum.ns are 69th, or closer, cousins. For people with recent European ancestry, the m.SA tim. m.y be only half as long, about 1000 years.

关键词： Population Structure Pairwise Shared Ancestry Genealogy m.gration m.st Recent Com.on Ancestor Hum.ns