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Reflections from the president of the International society of Zoological sciences:the zoology of zoonotic infectious diseases

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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

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 62M10 62P10

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

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

Evaluation of La AlO_3 as top coat material for thermal barrier coatings

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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

Perovskite is a versatile group of oxide materials allowing their properties to be tailored by composition towards specific requirements. La Al O3 was prepared to study and report its properties in the context of its potential in thermal barrier coatings（TBCs） technology. A citric acid method was used for synthesis and the perovskite structure was confirmed using XRD and FT-IR. Viscosity of the solution precursor was checked as well as the particle size by laser particle size analysis. Densification behavior of the material was followed by conventional sintering and by spark plasma sintering. Apparent porosity by the Archimedes method, thermal conductivity and thermal expansion coefficient were studied. Mechanical and fracture properties were measured at elevated temperatures up to 1300 ℃ For samples sintered at 1200-1400 ℃, coefficient of thermal expansion ranged from 5.5×10^-6 to 6.5×10^-6 k^-1 and thermal conductivity ranged between 2.2 and 3.4 W/（m？k）. Elastic modulus and ultimate stress were measured at 1000-1300 ℃, while by micro-indentation, fracture toughness was found to be 3 MPa·m1/2. As the sintering temperature increased from 1200 to 1500 ℃, significant densification from 3.21 to 5.81 g/cm^3 was found, indicating that material annealing should be made at least at 1400 ℃. Under this condition, negligible dimensional change in phase transition temperature of La Al O3 from the rhombohedral（R3 c） to the ideal cubic（Pm3 m） is found. Data reported in this work can be useful for comparing the mechanical and fracture behaviours of different TBCs developed involving La Al O3 as well as input for numerical simulations.

关键词： perovsldte lanthanum aluminate thermal barrier coating (TBC)

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

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营养生物发酵剂在乳品中的应用

中国食品工业 1997年第12期 42-43页

作者： chr.Hansen A/s

乳品经发酵变酸后,便具有更强的防腐能力,保质期更长。在发酵乳的生产中,一般都是采用乳酸菌进行发酵。经研究发现,有些乳酸菌能促进人体健康,这就是所谓的营养乳酸菌(probiotic lactic acid bacteria)。随着人们生活的富足,对加工食品... 详细信息

乳品经发酵变酸后,便具有更强的防腐能力,保质期更长。在发酵乳的生产中,一般都是采用乳酸菌进行发酵。经研究发现,有些乳酸菌能促进人体健康,这就是所谓的营养乳酸菌(probiotic lactic acid bacteria)。随着人们生活的富足,对加工食品的要求除了用以充饥外,更要求具有保健功能。富含营养乳酸菌的营养生物发酵剂除了能在任何发酵乳制品中引发发酵过程外,还能增加发酵乳已有的营养价值作用,其发展潜力非常广阔。

关键词：乳品发酵营养生物发酵剂发酵剂

Rank CFAR Detector in Presence of Randomly Arriving Impulse Interference

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Rank CFAR Detector in Presence of Randomly Arriving Impulse ...