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Integrative Zoology 2018年第5期13卷 604-611页

作者： Joacim nÄSLUnD niklas WEnGSTRÖM Fredrik WAHLQVIST david ALDVÉn LiborZÁVORKA Johan HÖJESJÖ Department of Biological and Environmental Sciences University of GothenburgGothenburgSweden Department of Ecosystem Biology University of South Bohemia inČeskéBudějoviceČeskéBudějoviceCzech Republic Swedish Anglers Association GothenburgSweden

Movement activity levels of wild animals often differ consistently among individuals,reflecting different behavioral *** studies have shown that laboratory-scored activity can predict several ecologically relevant *** an experiment on wild brown trout Salmo trutta,spanning from June to October,we investigated how spring swimming activity,measured in a standardized laboratory test,related to relative recapture probability in *** on laboratory activity scores,individuals clustered into 2 groups,which showed contrasting patterns in the size-dependency of their recapture *** had a slightly positive effect on recapture probability for passive fish but a clear negative effect on active *** results show that the population structure in a cohort,in terms of relative proportions of behavioral types in different size classes,can vary over *** results of this study could depend on either selective mortality or ***,selective disappearance of individuals with specific phenotypes,regardless of the mechanism,will have implications for trout population management,such as stocking efficiency of hatchery fish with high growth rates or maintenance of fishways past migration barriers.

关键词： animal personality freshwater fish recapture rate Salmonidae size-dependency

The elphbolt ab initio solver for the coupled electron-phonon Boltzmann transport equations

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npj Computational Materials 2022年第1期8卷 236-244页

作者： nakib H.Protik Chunhua Li Miguel Pruneda david Broido Pablo Ordejón Catalan Institute of nanoscience and nanotechnology(ICn2) CSIC and BISTCampus Bellaterra8193BarcelonaSpain Department of Physics Boston CollegeChestnut HillBostonMA02467USA

elphbolt is a modern Fortran (2018 standard) code for efficiently solving the coupled electron–phonon Boltzmann transport equations from first *** results from density functional and density functional perturbation theory as inputs,it can calculate the effect of the non-equilibrium phonons on the electronic transport (phonon drag) and non-equilibrium electrons on the phononic transport (electron drag) in a fully self-consistent manner and obeying the constraints mandated by *** can calculate the lattice,charge,and thermoelectric transport coefficients for the temperature gradient and electric fields,and the effect of the mutual electron–phonon drag on these transport *** code fully exploits the symmetries of the crystal and the transport-active window to allow the sampling of extremely fine electron and phonon wave vector meshes required for accurately capturing the drag *** coarray feature of modern Fortran,which offers native and convenient support for parallelization,is *** code is compact,readable,well-documented,and extensible by design.

关键词： properties phonon equations

Stem cell differentiation and human liver disease

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World Journal of Gastroenterology 2012年第17期18卷 2018-2025页

作者： Wen-Li Zhou Claire n Medine Liang Zhu david C Hay Department of Gastroenterology Changzheng Hospital Second Military Medical University ofChina Shanghai 200003 China Medical Re-search Council Centre for Regenerative Medicine University ofEdinburgh Edinburgh EH 16 4UU Scotland United Kingdom

Human stem cells are scalable cell populations capable of cellular *** makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary *** an approach has the potential to improve our understanding of human biology and treating *** the future it may be possible to deploy novel stem cell-based approaches to treat human liver *** recent years,eff icient hepatic differentiation from human stem cells has been achieved by several research groups including our *** this review we provide an overview of the f ield and discuss the future potential and limitations of stem cell technology.

关键词： Differentiation Pluripotent stem cells Hepatocyte-like cells Liver development Polymer chemistry Regenerative medicine Transplantation Bio-artif icial liver

Predisposing factors’effects on mortality of oak (Quercus) and hickory (Carya) species in mature forests undergoing mesophication in Appalachian Ohio

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Forest Ecosystems 2021年第1期8卷 81-94页

作者： Don C.Radcliffe david M.Hix Stephen n.Matthews School of Environment and natural Resources The Ohio State University2021 Coffey RoadColumbus OH 43210USA School of Environmental and Forest Sciences University of WashingtonBox 352100Seattle WA 98195-2100USA

Background:Mature oak(Quercus spp.)and hickory(Carya spp.)trees are gradually being replaced by more shadetolerant tree species across the eastern U.S.,likely due to fire suppression and increased *** and hickories are highly valuable to wildlife;therefore,studying their mortality patterns can provide information on the longevity of habitat quality for many animal *** mortality has most often been studied following large oak decline events,but background mortality rates in forests with aging oak and hickory canopies warrant equal attention,especially in the context of widespread oak and hickory regeneration ***:We studied background mortality rates of five oak and one hickory species over a 23–25 year time period(1993–1995 to 2018),using 821/20th hectare permanent plots on the Marietta Unit of the Wayne national Forest in southeastern *** calculated mortality rates based on remeasurement of individual trees for white oak(Quercus alba),chestnut oak(Quercus montana),northern red oak(Quercus rubra),black oak(Quercus velutina),scarlet oak(Quercus coccinea),and pignut hickory(Carya glabra).For each of these species other than scarlet oak,we also modeled the relationships of mortality probability with a priori topographic,soil,stand structural,and individual tree covariates,using a mixed-effects logistic regression ***:The species with the highest mortality rate was scarlet oak(61.3%),followed by northern red oak(41.4%),black oak(26.7%),pignut hickory(23.9%),white oak(23.4%),and chestnut oak(19.1%).In our models,northern red oak mortality was associated with more mesic slope positions,shallower solums,more acidic soils,and older stand *** hickory and chestnut oak mortality rates were associated with higher basal areas on the plot,while white oak mortality showed the opposite ***:Our data suggest that red oak subgenus trees in mature forests of our area will become increasingly uncommon relative t

关键词： Mortality Quercus Carya Mesophication Wildlife habitat

Two-Factor Cancelable Biometrics Authenticator

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Journal of Computer Science & Technology 2007年第1期22卷 54-59页

作者：彭颖涵 Andrew T. B. J david n. C. L Faculty of Information Science and Technology Multimedia University dalan Ayev Keroh Lama 75450 Melaka Malaysia

Biometrics-based authentication system offers advantages of providing high reliability and accuracy. However the contemporary authentication system is impuissance to compromise. If a biometrics data is compromised, it cannot be replaced and rendered unusable. In this paper, a cancelable biometrics-based authenticator is proposed to solve this irrevocability issue. The proposed approach is a two-factor authentication system, which requires both of the random data and facial feature in order to access the system. In this system, tokenized pseudo-random data is coupled with momentbased facial feature via inner product algorithm. The output of the product is then discretized to generate a set of private binary code, coined as 2factor-Hashing code, which is acted as verification key. If this biometrics-based verification key is compromised, a new one can be issued by replacing a different set of random number via token replacement. Then, the compromised one is rendered completely useless. This feature offers an extra protection layer against biometrics fabrication since the verification code is replaceable. Experimental results demonstrate that the proposed system provides zero Equal Error Rate in which there is a clear separation in between the genuine and the imposter distribution populations.

关键词： cancelable biometrics face recognition Geometric moments,pseudo Zernike moment

Characterization and catalytic behavior of EDTA modified silica nanosprings (nS)-supported cobalt catalyst for Fischer-Tropsch CO-hydrogenation

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燃料化学学报 2018年第8期46卷 957-966页

作者： Abdulbaset M.Alayat Elena Echeverria david n.Mcllroy Armando G.McDonald Environmental Science University of IdahoMoscowID83844-3006United States Renewable Materials Program Department of Forest Rangeland and Fire Sciences University of IdahoMoscow ID 83844-1133 United States Department of Physics Oklahoma S

The effect of ethylene diamine tetraacetic acid(EDTA) modification on the physico-chemical properties and catalytic performance of silica nanosprings(nS) supported cobalt(Co) catalyst was investigated in the conversion of syngas(H^(2+) CO) to hydrocarbons by Fischer-Tropsch synthesis(FTS). The unmodified Co/nS and modified Co/nS-EDTA catalysts were synthesized via an impregnation method. The prepared Co/nS and Co/nS-EDTA catalysts were characterized before the FTS reaction by BET surface area,X-ray diffraction(XRD),transmission electron microscopy(TEM),temperature programmed reduction(TPR),X-ray photoelectron spectroscopy(XPS),differential thermal analysis(DTA) and thermogravimetric analysis(TGA) in order to find correlations between physico-chemical properties of catalysts and catalytic performance. FTS was carried out in a quartz fixedbed microreactor(H_2/CO of 2 ∶1,230 ℃ and atmospheric pressure) and the products trapped and analyzed by GC-TCD and GC-MS to determine CO conversion and reaction selectivity. The experimental results indicated that the modified Co/nS-EDTA catalyst displayed a more-dispersed phase of Co_3O_4 nanoparticles(10.9%) and the Co_3O_4 average crystallite size was about 12.4 nm. The EDTA modified catalyst showed relatively higher CO conversion(70.3%) and selectivity toward C_(6-18)(JP-8,Jet A and diesel) than the Co/nS catalyst(C_(6-14))(JP-4).

关键词：化学分析煤矿燃烧

Identifying the ground state structures of point defects in solids

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npj Computational Materials 2023年第1期9卷 2095-2105页

作者： Irea Mosquera-Lois Seán R.Kavanagh Aron Walsh david O.Scanlon Thomas Young Centre and Department of Chemistry University College London20 Gordon StreetLondon WC1H 0AJUK Thomas Young Centre and Department of Materials Imperial College LondonExhibition RoadLondon SW72AZUK

Point defects are a universal feature of *** identification is addressed by combining experimental measurements with theoretical *** standard modelling approach is,however,prone to missing the ground state atomic configurations associated with energy-lowering reconstructions from the idealised crystallographic *** ground states compromise the accuracy of calculated *** address this issue,we report an approach to navigate the defect configurational landscape using targeted bond distortions and *** of our workflow to eight materials(CdTe,GaAs,Sb_(2)S_(3),Sb_(2)Se_(3),CeO_(2),In_(2)O_(3),ZnO,anatase-TiO_(2))reveals symmetry breaking in each host crystal that is not found via conventional local minimisation *** point defect distortions are classified by the associated physico-chemical *** demonstrate the impact of these defect distortions on derived properties,including formation energies,concentrations and charge transition *** work presents a step forward for quantitative modelling of imperfect solids.

关键词： ground distortion solids

An integrative view of the signaling phenotype： Dynamic links between signals, physiology, behavior and social context

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Current Zoology 2014年第6期60卷 739-754页

作者： Maren n. VITOUSEK david M. ZOnAnA Rebecca J. SAFRAn Department of neurobiology and Behavior Comell University Ithaca New York 14853 USA Department of Ecology and Evolutionary Biology University of Colorado Boulder Colorado 80309 USA

Signal traits are often linked with the physiological state and behavior of their bearer. Direct examination of the causal links among these variables has provided substantial insight into the information content of signals, and into the costs and benefits of signal expression. Yet recent empirical work suggests that the social context in which signals are developed and displayed can play a major role not only in how signals are received, but also in coordinating and mediating the signaling phenotype itself. Here we review both well-established and emerging evidence for direct feedbacks among an individual＇s physiological state, be- havior, and signal elaboration. We then describe an integrative view of signaling that takes into account the bidirectional rela- tionships among components of phenotype and the social context in which signals are developed and displayed. Integrating dy- namic feedback between context and phenotype within models of the evolution and maintenance of signals may yield insights into how signals evolve, how signaling phenotypes are coordinated and maintained on ecological and evolutionary time scales, and how static signals continue to convey relevant phenotypic information about their bearer through time.

关键词： Behavior Phenotype Physiology Signal trait Social feedback Sexual selection

Capacity of Old Trees to Respond to Environmental Change

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Journal of Integrative Plant Biology 2008年第11期50卷 1355-1364页

作者： nathan G.Phillips Thomas n.Buckley david T.Tissue Centre for Plant and Food Science University of Western Sydney Department of Geography and Environment Boston University Department of Biology Sonoma State University School of Biological Earth and Environmental SciencesUniversity of New South Wales Bushfire Cooperative Research Centre

Atmospheric carbon dioxide [CO2] has increased dramatically within the current life spans of long-lived trees and old forests. Consider that a 500-year-old tree in the early twenty-first century has spent 70% of its life growing under preindustrial levels of [CO2], which were 30% lower than current levels. Here we address the question of whether old trees have already responded to the rapid rise in [CO2] occurring over the past 150 years. In spite of limited data, aging trees have been shown to possess a substantial capacity for increased net growth after a period of post-maturity growth decline. Observations of renewed growth and physiological function in old trees have, in some instances, coincided with Industrial Age increases in key environmental resources, including [CO2], suggesting the potential for continued growth in old trees as a function of continued global climate change.

关键词： carbon dioxide hydraulic limitation old growth stomata tree rings.

Highly Efficient L-Band Fibre -DFB Lasers

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光学学报 2003年第S1期23卷 379-380页

作者： Morten Ibsen david J. Richardson david n. Payne ORC - University of Southampton Southampton SO17 1BJ United Kingdom. Also with Southampton Photonics Ltd. Southampton SO16 4NS United Kingdom.ORC - University of Southampton Southampton SO17 1BJ United Kingdom. Also with Southampton Photonics Ltd. Southampton SO16 4NS United Kingdom.ORC - University of Southampton Southampton SO17 1BJ United Kingdom. Also with Southampton Photonics Ltd. Southampton SO16 4NS United Kingdom.

A more than 12 mW highly efficient fibre-DFB laser operating at 1618.3 nm is fabricated and characterised. Its high-power, low-noise and single-polarisation characteristics make it very suitable WDM-source for L-band ... 详细信息

关键词： DFB Lasers high in for Highly Efficient L-Band Fibre WDM RIn