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Integrative Zoology 2022年第2期17卷 328-329页

作者： Nils chr.sTENsETH Professor of Ecology and Evolution at the Centre for Ecological and Evolutionary synthesis(CEEs) University of OsloNorway Professor of Marine Biology at the Centre for Coastal Research(CCR) University of AgderKristiansandNorway President of the International society of Zoological sciences

The past 2 years we now have behind us have demonstrated the importance of understanding the dynamics of zoonotic diseases in the wild and how the disease agents spill over to the human *** the end of 2021,Integrative Zoology published 2 special subsections on this topic,one of which focuses on plague—a zoonotic infectious disease which through history has ravaged the ***,caused by the bacterium Yersinia pestis,continues to cause deaths among people.I am quite confident that we will not get rid of wildlife plague,but human plague epidemics might be history in the not too distant future(Baril et al.2019;Vallès et al.2020).

关键词： population Reflections

Computer simulation of the coagulation of suspended solids——The applicability of the Müller–smoluchowski theory

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Journal of Environmental sciences 2016年第6期28卷 197-203页

作者： Regina Wardzynska Beata Zaleska-chróst Department of Chemistry University of Warmia and Mazury in Olsztyn

The results of studies carried out using a computer programme simulating the coagulation of suspensions containing spherical sol particles and spherical coagulant particles are *** influence of the degree of dispersion of the system on the coagulation reaction kinetics was investigated. The obtained results of kinetic studies were tested in the light of classical Müller–smoluchowski equations. The influence of the physical properties of the coagulant,such as size, density and mass, on the coagulation rate was tested. It was found that within the range described in this paper, the rate of the simulated coagulation process fulfils both the kinetic equation of a first-order reaction, and the kinetic equation of a second-order *** the tested range, a significant influence of the mass and size of the coagulant on the coagulation rate was ascertained. The kinetic Müller–smoluchowski dependence is fulfilled in a broader range of the degree of dispersion, when the coagulant particle mass and the sol particle mass are equal. When the particle mass increases with an increase in the particle radius, the coagulation rate increases faster that it would result from the Müller＇s dependence.

关键词： Aggregation Computer simulation Coagulation rate sol

Analyzing short time series data from periodically fluctuating rodent populations by thresholdmodels: A nearest block bootstrap approach

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science China Mathematics 2009年第6期52卷 1085-1106页

作者： CHAN kung-sik TONG Howell sTENsETH Nils chr Department of statistics and Actuarial science The University of IowaIowa CityIA 52242USA Department of statistics London School of Economics & the University of Hong KongHong KongChina Centre for Ecological and Evolutionary synthesis(CEEs) Department of BiologyUniversity of OsloP.O.Box 1066 BlindernN-0316 OsloNorway

The study of the rodent fluctuations of the North was initiated in its modern form with Elton's pioneering *** scientific studies have been designed to collect yearly rodent abundance data,but the resulting time series are generally subject to at least two "problems":being short and *** explore the use of the continuous threshold autoregressive(TAR) models for analyzing such *** the simplest case,the continuous TAR models are additive autoregressive models,being piecewise linear in one lag,and linear in all other *** location of the slope change is called the threshold *** continuous TAR models for rodent abundance data can be derived from a general prey-predator model under some simplifying *** lag in which the threshold is located sheds important insights on the structure of the prey-predator *** propose to assess the uncertainty on the location of the threshold via a new bootstrap called the nearest block bootstrap(NBB) which combines the methods of moving block bootstrap and the nearest neighbor *** NBB assumes an underlying finite-order time-homogeneous Markov ***,the NBB bootstraps blocks of random block sizes,with each block being drawn from a non-parametric estimate of the future distribution given the realized past bootstrap *** illustrate the methods by simulations and on a particular rodent abundance time series from kilpisjrvi,Northern Finland.

关键词： AIC continuous threshold autoregressive model non-nested hypotheses partial residual plots

Investigations on the Corrosion Behaviour and structural Characteristics of Low Temperature Nitrided and Carburised Austenitic stainless steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： D. Mnter H.-J. spies H. Biermann chr. Eckstein Department of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

The wear resistance of austenitic stainless steels can be improved by thermo-chemical surface treatment with nitrogen and carbon. However, it is possible that the corrosion resistance will be impaired by the precipitation of chromiumnitrid or -carbide. The present contribution deals with investigations of the corrosion behaviour and structural characteristics of a low temperature nitrided and carburised austenitic stainless steel. The material investigated was AIsI 316L (X2CrNiMol7-12-2) austenitic stainless steel. A commercial plasma-nitriding unit (pulsed dc) was used for the nitriding and carburising process. Additional samples were treated by the gasoxinitriding process for a comparison between plasma- and gasoxinitriding. The nitrided and carburised layer of austenitic stainless steel consists of the nitrogen or carbon s-phase (expanded austenite), respectively. X-ray diffraction investigations show the typical shift of the peaks to lower angles, indicating expansion of the fee lattice. Also the X-ray diffraction technique was employed to study the residual stresses in the nitrogen and carbon s-phase. The corrosion behaviour of surface engineered samples was investigated with electrochemical methods. Anodic potentiodynamic polarisation curves were recorded for testing the resistance against general corrosion (in H2sO4) and pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力

Diversity of arbuscular mycorrhizal fungi associated with desert ephemerals growing under and beyond the canopies of Tamarisk shrubs

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Chinese science Bulletin 2006年第A1期51卷 132-139页

作者： sHI Zhaoyong ZHANG Liyun FENG Gu chr stie Peter TIAN Changyan LI Xiaolin Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China College of Resources and Environmental sciences China Agricultural University Beijing 100094 China Agricultural and Environmental science Department Queen's University Belfast Belfast BT9 PX UK

arbuscular mycorrhizal (AM ) 四很普通的短暂植物种的真菌的地位， Chorispora tenella (棺罩) DC， Cerato-cephalus testiculatus (Crantz ) 贝丝， Eremopyrum 面向(L) Jaub et spash 和在树柳属植物灌木(Tamarix spp ) 统治的一个区域成长的维朗妮卡 campy-lopoda Boiss 被调查。四 ephemerals 和他们的根围土壤的样品从在下面并且在 Tamariskshrubs 的华盖以外被收集。植物 mycorrhizal 地位和土壤 AM 真菌的孢子密度和社区结构被分析并且比较在下面并且在灌木华盖以外。在他们的相应根围土壤的 ephemerals 和孢子密度的 mycorrhizal 殖民率在灌木华盖下面是显著地更低的比在远处。在灌木(12 ) 下面的 AM 真菌的种类的数字也比在华盖(19 ) 以外低。什么时候在四 ephemerals 的根围玷污性质，被检验的、可得到的 N 和 P 和全部的 P，有机物内容，全部的盐内容和电的电导率(EC ) 都在华盖下面是更高的比在远处。相反，玷污显示出的可得到的 k 和酸碱值没有如此的趋势。上午 21 点的一个总数真菌的种类从四 ephemerals 的根围土壤被孤立。五属于 Acaulospora，到 Archaeo-spora， 13 到血管球并且二到 Paraglomus。我们得出结论 Tamarix spp 的华盖。对 ephemerals 的 AM 地位并且在 AM 真菌的社区和一些他们的根围土壤的性质上施加了一些影响。

关键词：灌木真菌短生植物树冠撑柳

Contrasting phenology responses to climate warming across the northern extra-tropics

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Fundamental Research 2022年第5期2卷 708-715页

作者： Xiaojun Geng Yaru Zhang Yongshuo H.Fu Fanghua Hao Ivan A.Janssens Josep Penuelas shilong Piao Jing Tang Zhaofei Wu Jing Zhang Xuan Zhang Nils chr.stenseth College of Water sciences Beijing Normal UniversityBeijing 100875China General Institute of Water Resources and Hydropower Planning and Design(GIWP) Ministry of Water ResourcesBeijing 100053China Plants and Ecosystems Department of BiologyUniversity of AntwerpAntwerpBelgium CREAF Cerdanyola del VallèsBarcelona 08193CataloniaSpain CsIC Global Ecology Unit CREAF-CSIC-UABBellaterraBarcelona 08193CataloniaSpain Pecking University Beijing100847China Department of Physical Geography and Ecosystem science Lund UniversitySE22362 LundSweden Terrestrial Ecology section Department of BiologyUniversity of CopenhagenDK2100CopenhagenDenmark Center for Permafrost(CENPERM) University of CopenhagenDK1350CopenhagenDenmark Centre for Ecological and Evolutionary synthesis(CEEs) Department of BiosciencesUniversity of OsloN-0316 OsloNorway

Climate warming has substantially advanced the timing of spring leaf-out of woody species at middle and high latitudes,albeit with large *** in the spatial variation of this climate warming response may therefore help to constrain future trends in leaf-out and its impact on energy,water and carbon balances at global *** this study,we used in situ phenology observations of 38 species from 2067 study sites,distributed across the northern hemisphere in China,Europe and the United states,to investigate the latitudinal patterns of spring leaf-out and its sensitivity(s T,advance of leaf-out dates per degree of warming)and correlation(R_(T),partial correlation coefficient)to temperature during the period *** all species and sites,we found that s_(T) decreased significantly by 0.15±0.02 d℃^(-1)°N^(-1),and R_(T) increased by 0.02±0.001°N^(-1)(both at Ps in R_(T) and s_(T) were explained by the differences in requirements of chilling and thermal forcing that evolved to maximize tree fitness under local climate,particularly climate predictability and summed precipitation during the pre-leaf-out *** results thus showed complicated spatial differences in leaf-out responses to ongoing climate warming and indicated that spatial differences in the interactions among environmental cues need to be embedded into large-scale phenology models to improve the simulation accuracy.

关键词： Apparent temperature sensitivity Latitudinal pattern Leaf-out Temperate tree Climate change

Very Original Proofs of Two Famous Problems: “Are There Any Odd Perfect Numbers?” (Unsolved until to Date) and “Fermat’s Last Theorem: A New Proof of Theorem (Less than One and a Half Pages) and Its Generalization”

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Advances in Pure Mathematics 2021年第11期11卷 891-928页

作者： Demetrius chr. Poulkas Department of Mathematics Aristotle University of Thessaloniki Thessaloniki Greece school of Electrical and Computer Engineering National Technical University of Athens Athens Greece school of the Faculty of Engineering Aristotle University of Thessaloniki Thessaloniki Greece Department of Mechanical Engineering and Aeronautics Faculty of Engineering University of Patras Patra Greece

This article presents very original and relatively brief or very brief proofs about of two famous problems: 1) Are there any odd perfect numbers? and 2) “Fermat’s last theorem: A new proof of theorem and its generalization”. They are achieved with elementary mathematics. This is why these proofs can be easily understood by any mathematician or anyone who knows basic mathematics. Note that, in both problems, proof by contradiction was used as a method of proof. The first of the two problems to date has not been resolved. Its proof is completely original and was not based on the work of other researchers. On the contrary, it was based on a simple observation that all natural divisors of a positive integer appear in pairs. The aim of the first work is to solve one of the unsolved, for many years, problems of the mathematics which belong to the field of number theory. I believe that if the present proof is recognized by the mathematical community, it may signal a different way of solving unsolved problems. For the second problem, it is very important the fact that it is generalized to an arbitrarily large number of variables. This generalization is essentially a new theorem in the field of the number theory. To the classical problem, two solutions are given, which are presented in the chronological order in which they were achieved. Note that the second solution is very short and does not exceed one and a half pages. This leads me to believe that Fermat, as a great mathematician was not lying and that he had probably solved the problem, as he stated in his historic its letter, with a correspondingly brief solution. To win the bet on the question of whether Fermat was telling truth or lying, go immediately to the end of this article before the General Conclusions.

关键词： Perfect Numbers Odd Perfect Numbers Fermat’s Last Theorem Generalization of the Fermat’s Last Theorem Prime Number Problems Millennium Problems

LaAlO_3作为热障涂层顶级涂层材料的评价（英文）

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Transactions of Nonferrous Metals society of China 2018年第8期28卷 1582-1592页

作者： N.VOURDAs E.MARATHONITI P.k.PAndIs chr.ARGIRUsIs G.sOURkOUNI C.LEGROs s.MIRZA V.N.sTATHOPOULOs Laboratory of Chemistry and Materials Technology School of technological ApplicationsTechnological Educational Institute of Sterea Ellada 34400 Psachna Campus Evia Greece school of Chemical Engineering national Technical University of Athens I. Polytectmeiou 9 15780 Zografou Athens Greece Inst. f. Metallurgie Technische Universitat Clausthal Robert-Koch-Str. 42 38678 Clausthal-Zellerfeld Germany Institut de Chimie Moleculaire et des Materiaux d'Orsay université Paris Sud Bt 410 91405 Orsay Cedex France ELEMENT s.A. Hitchin SG4 0TW UK

钙钛矿是一种多用途氧化物材料,可以通过调整成分而改变其性能以满足特定的需求。采用柠檬酸法制备La AlO_3,用XRD和FT-IR检测确认其钙钛矿结构,并评估其用于热障涂层(TBC)技术所需的性能。检测溶液前驱物的粘度并通过激光粒度仪分析其... 详细信息

钙钛矿是一种多用途氧化物材料,可以通过调整成分而改变其性能以满足特定的需求。采用柠檬酸法制备La AlO_3,用XRD和FT-IR检测确认其钙钛矿结构,并评估其用于热障涂层(TBC)技术所需的性能。检测溶液前驱物的粘度并通过激光粒度仪分析其粒度。采用传统烧结和放电等离子烧结使材料致密化。用阿基米德法测试材料的表观孔隙率,并测试材料的导热系数和热膨胀系数。测试材料的高温(最高达1300°C)力学性能和断裂性能。结果表明,在1200~1400°C烧结的样品,其热膨胀系数为(5.5~6.5)×10^(-6) k^(-1),热导率为2.2~3.4 W/(m·k)。在1000~1300°C范围内测量弹性模量和极限应力,通过微压痕测算的断裂韧性约为3 MPa/m1/2。热处理温度从1200°C提高到1500°C,材料发生明显致密化,密度从3.21 g/cm3提高到5.81 g/cm^3,表明材料热处理的最低温度应为1400°C。在相变温度下,La AlO_3从菱方结构(R3c)转变为理想的立方结构(Pm3m),而其晶格尺寸的变化可以忽略。本研究报道的数据可用于比较涉及La AlO_3的不同TBC的力学和断裂行为,也可用于数值模拟。

关键词：钙钛矿铝化镧热障涂层(TBC)

Evaluating the effectiveness of control measures in multiple regions during the early phase of the COVID-19 pandemic in 2020

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Biosafety and Health 2021年第5期3卷 264-275页

作者： Zengmiao Wang Jason Whittington Hsiang-Yu Yuan Hui Miao Huaiyu Tian Nils chr.stenseth state key Laboratory of Remote sensing science Center for Global Change and Public HealthCollege of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100091China Centre for Ecological and Evolutionary synthesis(CEEs) Department of BiosciencesUniversity of OsloOslo N-0315Norway Department of Biomedical sciences Jockey Club College of Veterinary Medicine and Life SciencesCity University of Hong KongHong Kong 999077China Department of statistics College of Art and ScienceOhio State UniversityColumbusOH 43210USA

The number of COVID-19 confirmed cases rapidly grew since the sARs-CoV-2 virus was identified in late *** to the high transmissibility of this virus,more countries are experiencing the repeated waves of the COVID-19 ***,with limited manufacturing and distribution of vaccines,control measures might still be the most critical measures to contain outbreaks ***,evaluating the effectiveness of various control measures is necessary to inform policymakers and improve future *** addition,there is an ongoing need to enhance our understanding of the epidemiological parameters and the transmission patterns for a better response to the COVID-19 *** review focuses on how various models were applied to guide the COVID-19 response by estimating key epidemiologic parameters and evaluating the effectiveness of control *** also discuss the insights obtained from the prediction of COVID-19 trajectories under different control measures scenarios.

关键词： COVID-19 Models Application

A Brief New Proof to Fermat’s Last Theorem and Its Generalization

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Journal of Applied Mathematics and Physics 2020年第4期8卷 684-697页

作者： Demetrius chr. Poulkas Department of Mathematics of Aristotle University of Thessaloniki Thessaloniki Greece school of the Faculty of Engineering of Aristotle University of Thessaloniki Thessaloniki Greece school of Electrical and Computer Engineering of National Technical University of Athens Athens Greece Department of Mechanical Engineering and Aeronautics of Faculty of Engineering of University of Patras Patra Greece

This article presents a brief and new solution to the problem known as the “Fermat’s Last Theorem”. It is achieved without the use of abstract algebra elements or elements from other fields of modern mathematics of the twentieth century. For this reason it can be easily understood by any mathematician or by anyone who knows basic mathematics. The important thing is that the above “theorem” is generalized. Thus, this generalization is essentially a new theorem in the field of number theory.

关键词： Brief Proof of Fermat’s Last Theorem Unsolved Mathematical Problems Fermat’s Last Theorem Generalization of the Fermat’s Last Theorem Prime Number Problems Millennium Problems