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The Chapman-Richards Distribution and its Relationship to the Generalized Beta

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Forest Ecosystems 2019年第3期6卷 219-235页

作者： Jeffrey h.Gove thomas B.Lynch Mark J.Ducey USDA Forest Service Northern Research Station271 Mast Road Durham 03824NHUSA Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA Department of Natural Resources and the Environment University of New Hampshire114 James Hall Durham 03824NHUSA

Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptions of the Chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distribution. Therefore, unlike 'assumed' distribution models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the Chapman-Richards distribution can be recast as a subset of the generalized beta distribution of the first kind, a rich family of assumed probability distribution models with known properties. These known properties for the generalized beta are then immediately available for the Chapman-Richards distribution, such as the form of the compatible basal area-size distribution. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possible distribution shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilibrium assumption. The parameter estimates are shown to depend on both the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat by distribution shape, with the smaller, noisier samples providing less reliable estimates of the vital rates and final distribution forms. Conclusions: The Chapman-Richards distribution in its original form, or recast as a generalized beta form, presents a potentially useful model integrating vital rates and stand diameters into a flexible family of resultant distributions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are obtained.

关键词： Diameter distributions Chapman-Richards growth Generalized beta distribution of the first kind Maximum likelihood McKendrick-Von Foerster equation Physiologically structured population model Size-structured distributions

Time-Resolved Oxidation State Changes Are Key to Elucidating the Bifunctionality of Perovskite Catalysts for Oxygen Evolution and Reduction

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Energy & Environmental Materials 2024年第5期7卷 292-300页

作者： Casey E.Beall Emiliana Fabbri Adam h.Clark Vivian Meier Nur Sena Yüzbasi Benjamin h.Sj∅lin Ivano E.Castelli Dino Aegerter thomas Graule thomas J.Schmidt Paul Scherrer Institute(PSI) 5232Villigen PSISwitzerland Institute for Physical Molecular Science ETH Zürich8093ZürichSwitzerland Empa 8600DübendorfSwitzerland Department of Energy Conversion and Storage Technical University of DenmarkDK-2800Kgs.LyngbyDenmark

In a unified regenerative fuel cell(URFC)or reversible fuel cell,the oxygen bifunctional catalyst must switch reversibly between the oxygen reduction reaction(ORR),fuel cell mode,and the oxygen evolution reaction(OER),electrolyzer ***,it is often unclear what effect alternating between ORR and OER has on the electrochemical behavior and physiochemical properties of the ***,operando X-ray absorption spectroscopy(XAS)is utilized to monitor the continuous and dynamic evolution of the Co,Mn,and Fe oxidation states of perovskite catalysts Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)(BSCF)and La_(0.4)Sr_(0.6)MnO_(3-δ)(LSM),while the potential is oscillated between reducing and oxidizing potentials with cyclic *** results reveal the importance of investigating bifunctional catalysts by alternating between fuel cell and electrolyzer operation and highlight the limitations and challenges of bifunctional *** is shown that the requirements for ORR and OER performance are divergent and that the oxidative potentials of OER are detrimental to ORR *** findings are used to give guidelines for future bifunctional catalyst ***,it is demonstrated how sunlight can be used to reactivate the ORR activity of LSM after rigorous cycling.

关键词： BSCF LSM OER ORR XAS

植物系统发生海报——以演化视角介绍植物多样性的科教资料项目

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生物多样性 2025年

作者：蒋陈焜郁文彬饶广远黎怀成 Julien B.Bachelier hartmut h.hilger Theodor C.h.Cole 北京大学生命科学学院蛋白质与植物基因研究国家重点实验室北京大学前沿交叉学科研究院北京大学-清华大学生命科学联合中心中国科学院西双版纳热带植物园综合保护中心/云南省热带雨林与亚洲象保护重点实验室 Dahlem Centre of Plant Sciences (DCPS)， Institute of Biology， Structural and Functional Plant Diversity， Freie Universit?t Berlin

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而， ... 详细信息

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而，现有资料多集中于物种的识别、鉴定与分类，缺乏从生物演化角度对植物多样性进行系统性介绍的内容。本文介绍了一个具有全球影响力的科教资料案例——由美裔德国植物学家Theodor C. h. Cole发起的植物系统发生海报(Plant Phylogeny Posters)项目。该项目通过整合最新的系统与演化植物学研究成果，以系统发生为线索介绍植物多样性及其亲缘关系，旨在利用系统发生树所蕴含的丰富演化思想内涵，启发读者理解植物多样性与演化。海报以系统发生树结合植物类群的形态、地理分布、物种数量等数据信息，直观展示了多个分类等级的重要类群的演化历史。在数十所大学和科研机构的45位研究人员的努力下， 70张系统发生海报已被翻译成中文，并向所有人免费开放获取。这一科教项目有望为增进公众深入理解植物多样性及其保护行动提供宝贵的资源和帮助。

关键词：植物多样性演化系统发生科教资料

Fore-aft asymmetry of the ~2h(n,γ)~3h at very low energies

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Chinese Physics C 2013年第9期37卷 13-18页

作者： h.Khalili h.Sadeghi Department of Physics Faculty of ScienceArak University

We have used the recent effective field theory （EFT） which is constructed from two- and three-nucleon interactions, using minimal substitution in the momentum dependence of these interactions. We present the calcula- tions of the fore-aft asymmetry of γ-rays in the reaction 2h（n,γ）3h which are based on EFT up to next-to-next-to leading order （N2LO）. The results are compared with the recently reported calculations and measurements of the fore-aft asymmetry of T-rays from neutron-deuteron radiative capture. The calculated fore-aft asymmetry of the nd radiative capture process above deuteron breakup threshold is in good agreement with the available experimental data up to 20 MeV.

关键词： effective field theory neutron-deuteron radiative capture photonuclear observables fore-aft asymmetry

Photon Linear Polarization Coefficient of the Radiative Capture Process ^(2)h(p,γ)^(3)he at Thermal Energies

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Chinese Physics Letters 2012年第12期29卷 52-56页

作者： h.Sadeghi Department of Physics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

The photon polarization parameter of the proton-deuteron radiative capture process at thermal proton energies is calculated up to leading order(LO),using pionless effective field theory(EFT).In order to make a comparative study of this model,we compare our results for the photon polarization parameter with the realistic Argonne(AV14)and Argonne v18(AV18)modern nucleon-nucleon potentials and Urbana IX or Tucson-Melbourne three-nucleon *** theoretical description of the ^(2)h(p,γ)^(3)he reaction at thermal energies is complicated by the presence of the Coulomb *** the s-wave capture contribution to the thermal energy of this reaction is ***-body currents give small but significant contributions to some of the observables in the proton-deuteron radiative capture cross section at thermal neutron *** result is in good agreement with the available experimental data and potential models'calculation at this order.

关键词： interaction. radiative Polarization

S-Factor of the ^(3)h(α,γ)^(7)Li Reaction at Astrophysical Energies

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Chinese Physics Letters 2013年第10期30卷 59-62页

作者： h.Sadeghi Department of Physics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

The astrophysical S-factor forα-^(3)h radiative capture is calculated at astrophysical *** construct conserved two-and three-body electromagnetic currents,using minimal substitution in the explicit momentum dependence of the two-and three-nucleon *** realistic Argonne v_(18) two-nucleon and Urbana IX or Tucson–Melbourne three-nucleon interactions are considered for *** extrapolation of results for the astrophysical S-factor at zero energy,the energy in the order of 1 keV and less is found to be S(0)=0.107(0.112)keV·b,with(without)three-body interactions in satisfactory agreement with other theoretical results and experimental data.

关键词： calculation substitution momentum

KMAP-O framework for care management research of patients with type 2 diabetes

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World Journal of Diabetes 2017年第4期8卷 165-171页

作者： thomas T h Wan Amanda Terry Bobbie McKee Waleed Kattan College of health and Public Affairs University of Central Florida Florida hospital Creation health Research Center

AIM To review impacts of interventions involving self-management education, health coaching, and motivational interviewing for type 2 diabetes. METhODS A thorough review of the scientific literature on diabetes care and management was executed by a research team. RESULTS This article summarizes important findings in regard to the validity of developing a comprehensive behavioral system as a framework for empirical investigation. The behavioral system framework consists of patients' knowledge(K), motivation(M), attitude(A), and practice(P) as predictor variables for diabetes care outcomes(O). Care management strategies or health education programs serve as the intervention variable that directly influences K, M, A, and P and then indirectly affects the variability in patient care outcomes of patients with type 2 diabetes. CONCLUSION This review contributes to the understanding of the KMAP-O framework and how it can guide the care management of patients with type 2 diabetes. It will allow the tailoring of interventions to be more effective through knowledge enhancement, increased motivation, attitudinal changes, and improved preventive practice to reduce the progression of type 2 diabetes and comorbidities. Furthermore, the use of health information technology for enhancing changes in KMAP and communications is advocated in health promotion and development.

关键词： KMAP-O framework Type 2 diabetes Behavioral intervention strategies Causal mechanisms

Validity and reliability of the Dutch version of the displaced aggression questionnaire

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World Journal of Psychiatry 2021年第12期11卷 1288-1300页

作者： Danique Smeijers thomas F Denson Erik h Bulten Inti A Brazil Behavioural Science Institute Radboud UniversityNijmegen 6525 HRThe Netherlands Pompestichting Nijmegen 6532 CNThe Netherlands School of Psychology University of New South WalesSydney 2052Australia Radboud University Donders Institute for Brain Cognition and BehaviourNijmegen 6525 GDThe Netherlands

BACKGROUND Displaced aggression occurs when a person encounters a provoking situation,is unable or unwilling to retaliate against the original provocateur,and subsequently aggresses against a target that is not the source of the initial *** displaced aggression questionnaire(DAQ)was developed to measure individual differences in the tendency to displace *** To develop a Dutch version of the DAQ and examine relationships between the DAQ and novel individual *** The Dutch version of the DAQ was created using a back-translation *** students(n=413)participated in the current *** questionnaires were administered *** The results confirmed the original three-factor structure and showed good reliability and *** also found differential relationships between trait displaced aggression,social anxiety and cognitive *** The results may indicate that distinct patterns exist in the development of the different dimensions of trait displaced *** study adds to the growing cross-cultural literature showing the robustness of trait displaced aggression in several different cultures.

关键词： Displaced aggression questionnaire Displaced aggression Questionnaire Dutch translation Psychometric properties

Microstructure and long-term stability of Ni–YSZ anode supported fuel cells:a review

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Materials Futures 2022年第4期1卷 18-51页

作者： Sajad Vafaeenezhad Amir Reza hanifi Miguel A Laguna-Bercero thomas h Etsell Partha Sarkar Department of Chemical and Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada Instituto de Nanociencia y Materiales de Aragón(INMA) CSIC-Universidad de ZaragozaC/Pedro Cerbuna 12Zaragoza E-50009Spain

Nickel–yttria stabilized zirconia(Ni–YSZ)cermet is the most commonly used anode in solid oxide fuel cells(SOFCs).The current article provides an insight into parameters which affect cell performance and stability by reviewing and discussing the related publications in this *** the parameters which affect the microstructure of Ni–YSZ such as grain size(Leng et al 2003 *** Sources 11726–34)and ratio of Ni to YSZ,volume fraction of porosity,pore size and its distribution,tortuosity factor,characteristic pathway diameter and density of triple phase boundaries is the key to designing a fuel cell which shows high electrochemical *** of stability has been the main barrier to commercialization of SOFC *** influencing the degradation of Ni–YSZ supported SOFCs such as Ni migration inside the anode during prolonged operation are *** longest Ni-supported SOFC tests reported so far are examined and the crucial role of chromium poisoning due to interconnects,stack design and operating conditions in degradation of SOFCs is *** importance of calcination and milling of YSZ to development of porous structures suitable for Ni infiltration is explained and several methods to improve the electrochemical performance and stability of Ni–YSZ anode supported SOFCs are suggested.

关键词： long-term stability Ni YSZ microstructure SOFC anode