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Changshanian maximum Flooding Event in China and Its Global Correlation

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Acta Geologica Sinica(English Edition) 1996年第4期70卷 341-355,451页

作者： m.E.tucker U niverSity of Durhnm.U.K.

Various orders of condensed sections are recognized in the Cambrian of north China Carbonate Platform. Study of comparative sedimentology proves that CS4-CS5 in the Changshanian age is the maximum sea flooding sediments in the Cambrian, regardless of the distribution, thickness, internal structure of the condensed section series and K2O abundance. It is a two-layered composite condensed section series, characterized by the enrichment of such elements as K, P, mn, Ti, Co, V, Cr, Cu, Zr, ni, Li, Th, La, Ce, nd, Dy, Y, Sc and Be. The Changshanian maximum flooding event can be correlated on a global scale, and the corresponding sedimentary records are discovered in 26 intercontinental sections in n. Europe, n. America, and Tarim and the Yangtze Platform of China. Through detailed sedimentological research, meter-scale cycle analysis and Fischer plots, it is concluded that the Changshanian maximum flooding was a composite effect of the second-order eustacy superimposed by the third-and fourth-order eustacy, which lasted for 1.2-3 ma. An intercontinental model of the Changshanian maximum flooding is proposed at the end of this paper.

关键词： Changshanian age maximum flooding event condensed section global correlation Cambrian

Dual-shell silicate and alumina coating for long lasting and high capacity lithium ion batteries

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Journal of Energy Chemistry 2022年第5期31卷 314-323页

作者： marcos Lucero tucker m.holst.n Yudong Yao Ryan Faase maoyu Wang Alpha T.n’Diaye David P.Cann Joe Baio Junjing Deng Zhenxing Feng School of Chemical Biologicaland Environmental EngineeringOregon State UniversityCorvallisOR 97331United States Advanced Photon Source Argonne National LaboratoryArgonneIllinois 60439United States Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720United States materials Science School of MechanicalIndustrialand Manufacturing EngineeringOregon State UniversityCorvallisOR 97331United States

Here we demonstrate a theory-driven, novel dual-shell coating system of Li_(2)SrSiO_(4) and Al_(2)O_(3), achieved via a facile and scalable sol-gel technique on LiCoO_(2) electrode particles. The optimal thickness of each coating can lead to increased specific capacity(~185 m Ah/g at 0.5 C-rate) at a cut-off potential of 4.5 V, and greater cycling stability at very high C rates(up to 10 C) in half-cells with lithium metal. The mechanism of this superior performance was investigated using a combination of X-ray and electron characterization methods. It shows that the results of this investigation can inform future studies to identify still better dual-shell coating schemes, achieved by such industrially feasible techniques, for application on similar, nickel-rich cathode materials.

关键词： Lithium cobalt oxide Surface coating Sol-gel Silicate Alumina X-ray absorption spectroscopy

The evolution of sexual imprinting in socially monogamous populations

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Current Zoology 2015年第6期61卷 1043-1061页

作者： Edith InVERnIZZI R. tucker GILmAn Faculty of Life Sciences University of Manchester C. 1249a Michael Smith Building Dover Street Manchester M 13 9PL UK

Sexual imprinting is a common mechanism of mate preference learning. It is thought to influence how traits evolve and in some cases to promote speciation. Recently there has been increasing interest in how sexual imprinting itself evolves. Theoretical work on polygynous mating systems predicts that females will evolve paternal imprinting, which means they learn to prefer phenotypes expressed by their fathers. In nature however, females of some species learn to prefer phenotypes expressed by their mothers instead. We used a dynamical systems model and tools from adaptive dynamics to study how sexual imprinting evolves in species with socially monogamous mating systems. We considered cases in which the target trait for imprinting is un- der viability selection but is not a reliable signal of paternal investment. Thus, the target trait signals the genetic benefits rather than the parental care benefits of mate choice. When mating is socially monogamous and there is some extra-pair patemity, we show that maternal imprinting can be favored over paternal imprinting. Counterintuitively, females often become choosier when selecting social partners in systems where extra-pair mating is more frequent. That is, females may be more selective when choosing social partners that will sire a smaller percentage of their offspring. Our results offer new testable hypotheses, and ad- vance our understanding of the mechanisms that drive the evolution of mate choice strategies in nature .

关键词： Sexual imprinting mate preference learning monogamy Extra-pair mating Evolution model

Encouraging kids to hop,skip,and jump：Emphasizing the need for higher-intensity physical activity in childcare

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Journal of Sport and Health Science 2018年第3期7卷 333-336页

作者： molly Driediger Leigh m.Vanderloo Stephanie Truelove Brianne A.Bruijns Patricia tucker school of occupational therapy university of western ontario elborn collegeLondonOntario N6G 1H1Canada child health and evaluative sciences the hospital for sick childrenTorontoON M5G OA4Canada health and rehabilitation sciences university of western ontario elborn collegeLondon.Ontario N6G 1H1Canada

*** Daily physical activity（PA）participation is crucial to the health and well-being of young *** with total physical activity（TPA;all-intensity）,moderate-to-vigorous physical activity（mVPA）,or energetic play,is associated with greater health benefits,particularly for preschoolers（3-4 years）,including but not limited to improved bone and skeletal properties and cognitive and psychosocial health.1 Centered on this,both Canada and Australia have recently established 24-Hour movement Guidelines for the Early Years,recommending that.

关键词： Encouraging kids to hop,skip,and jump:Emphasizing the need for higher-intensity physical activity in childcare

milankovitch-driven cycles in the Precambrian of China:The Wumishan Formation

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Journal of Palaeogeography 2013年第4期2卷 369-389页

作者： mei mingxiang maurice E. tucker State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences (Beijing) Department of Earth Sciences University of Durham

Carbonate strata of the mesoproterozoic Wumishan Formation in the Jixian area near Tianjin are ~3300 m thick and were deposited over some 100 million years(from ~1310±20 ma to ~1207±10 ma).metre-scale cycles(parasequences) dominate the *** are generally of the peritidal carbonate type,and mostly show an approximately symmetrical lithofacies succession with thick stromatolite biostromes and small thromboliteoncolite bioherms constituting the central part and tidal-flat dolomites forming the upper and lower ***-supratidal dolomitic shales with palaeosol caps make up the topmost *** boundaries of the Wumishan cycles are typically exposure surfaces,and there is abundant evidence for fresh-water *** 1:4 stacking patterns indicate that the individual Wumishan cycles are sixthorder parasequences,with 4 parasequences constituting one fifth-order parasequence ***,5-8 beds or couplets,can be discerned in some of the *** regular vertical stacking pattern of beds within the sixth-order parasequences,forming the fifth-order parasequence sets,are interpreted as the result of environmental fluctuations controlled by milankovitch rhythms,namely the superimposition of precession,and short and *** widespread 1:4 stacking pattern in the cyclic succession,as well as the local 1:5-8 stacking patterns of the beds within the cycles,suggest that the milankovitch rhythms had similar ratios in the mesoproterozoic as in the *** on the cycle stacking patterns,26 thirdorder sequences can be distinguished and these group into 6 second-order,transgressiveregressive megasequences(or sequence sets),all reflecting a composite,hierarchical succession of relative sea-level changes.

关键词： peritidal carbonate cycles milankovitch rhythms Wumishan Formation mesoproterozoic Tianjin north China

The importance of large-diameter trees to the creation of snag and deadwood biomass

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Ecological Processes 2021年第1期10卷 380-393页

作者： James A.Lutz Soren Struckman Sara J.Germain tucker J.Furniss Department of Wildland Resources S.J.and Jessie E.Quinney College of Natural ResourcesUtah State University5230 Old Main HillLoganUT 84322-5230USA

Background:Baseline levels of tree mortality can,over time,contribute to high snag densities and high levels of deadwood(down woody debris)if fire is infrequent and decomposition is *** can be important for tree recruitment,and it plays a major role in terrestrial carbon cycling,but deadwood is rarely examined in a spatially explicit ***:Between 2011 and 2019,we annually tracked all trees and snags≥1 cm in diameter and mapped all pieces of deadwood≥10 cm diameter and≥1 m in length in 25.6 ha of Tsuga heterophylla/Pseudotsuga menziesii *** analyzed the amount,biomass,and spatial distribution of deadwood,and we assessed how various causes of mortality that contributed uniquely to deadwood ***:Compared to aboveground woody live biomass of 481 mg ha^(−1)(from trees≥10 cm diameter),snag biomass was 74 mg ha^(−1) and deadwood biomass was 109 mg ha^(−1)(from boles≥10 cm diameter).Biomass from large-diameter trees(≥60 cm)accounted for 85%,88%,and 58%,of trees,snags,and deadwood,*** aboveground woody live and dead biomass was 668 mg ha^(−1).The annual production of downed wood(≥10 cm diameter)from tree boles averaged 4 mg ha^(−1) yr^(−1).Woody debris was spatially heterogeneous,varying more than two orders of magnitude from 4 to 587 mg ha^(−1) at the scale of 20 m×20 m *** all causes of deadwood creation varied in importance between large-diameter trees and small-diameter *** of standing stems and deadwood had weak inverse distributions,reflecting the long period of time required for trees to reach large diameters following antecedent tree mortalities and the centennial scale time required for deadwood ***:Old-growth forests contain large stores of biomass in living trees,as well as in snag and deadwood biomass pools that are stable long after tree *** biomass(or carbon)in deadwood pools can lead to substantial underestimations of sequestration and stability.

关键词： Carbon sequestration Old-growth forest Pseudotsuga menziesii Tree mortality Tsuga heterophylla Wind River Forest Dynamics Plot

Sustainability and Public Engagement in mining： The Role of Engineers

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Journal of Earth Science and Engineering 2015年第5期5卷 280-288页

作者： marcello m. Veiga Christopher tucker norman B. Keevil Institute of mining Engineering University of British Columbia Vancouver V6TI Z4 Canada

Social issues are increasingly recognized as significant inhibitors to mineral development projects. Increasingly, social risk is being recognized as a key factor determining the success of a mineral investment. Groups opposed to a mine for social or political reasons otten use environmental impacts, real or perceived, to prevent mine development. These risk factors depend largely on cultural perceptions of mining activities and must be understood as such in order to be appropriately managed. A first step to addressing social issues is inclusive, transparent and meaningful engagement of stakeholders. This process allows stakeholders to understand what the other parties value in order to collectively establish a common currency for development and the creation of mutual value. Expanding the scope of benefits and values a mine can bring is of increasing importance to mining companies who typically consult outside specialists remote from the mine site and late in the development timeline for this purpose. Training technical staff, engineers and geologists, who make initial and ongoing contact with local interests, in a holistic approach to mine development is crucial to successful and economic mineral development projects. Further extending this conversation to the genera/ public, media governments and non-govemmental organizations is a necessary step in developing a meaningful discourse on the benefit of mining activities.

关键词： Social issues in mining mining and society public engagement sustainability of mining.

Outcomes and impact of an advanced clinical ultrasound track in an emergency medicine residency

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World Journal of Emergency medicine 2024年第6期15卷 486-489页

作者： Charles W.Kropf David A.Haidar Ryan V.tucker William Peterson neil Khanna Rob D.Huang Christopher m.Fung nik Theyyunni Department of Emergency medicine University of Michigan Medical SchoolMichigan 48109USA Department of Emergency medicine University of ColoradoColorado 80045USA Department of Emergency medicine Henry Ford Health SystemMichigan 48109USA

Point-of-care ultrasound(POCUS)is a core component of emergency medicine(Em)residency training used to guide medical decision making and to enhance procedural competence.[1-3]many repetitions of POCUS exams are required to achieve competency,and it is difficult to quantify a minimum needed to achieve mastery.[4,5]For Em residents whose career goals require greater depth of knowledge and skill in POCUS,educators can consider expanded training through a professional development track.

关键词： repetition expanded impact

Carbonate sedimentation in a starved pull-apart basin,middle to Late Devonian,southern Guilin,South China

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Carbonate sedimentation in a starved pull-apart basin,Middle...