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Does the grasshopper Chorthippus brunneus adapt to metal polluted habitats？ A study of glutathione-dependent enzymes in grasshopper nymphs

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Insect Science 2009年第1期16卷 33-42页

作者： Maria Augustyniak Agnieszka Babczynska michal Augustyniak Department of Animal Physiology and Ecotoxicology University of Silesia Bankowa 9 40-007 Katowice Faculty of Earth Sciences University of Silesia Bedzinska 60 PL 41-200 Sosnowiec Poland

Glutathione contents and activity ofglutathione-dependent enzymes in the body of insects inhabiting polluted areas depend on toxin kind, concentration and exposure time. Enzymatic response may be modified by gender, age, developmental stage and state of nutrition. Also, chronic exposure to metals in the environment may cause the selection of individuals resistant to some environmental toxins. To assess the degree of adaptation of Chorthippus brunneus to metal-polluted habitats, we measured glutathione contents and the activity of selected glutathione-dependent enzymes in the offspring of aging mothers which differed in time and intensity of exposure to metals in their habitats. We tested whether differences represent temporal shifts in tolerance range or were genetically preserved and inherited by future generations. We investigated insects from three populations. Two live in heavily metal-burdened areas, exposed to metals for 170 （Szopienice） or 50 years （Olkusz） and the third inhabits an unpolluted reference site （Pilica）. The most important findings were age-by-site interactions for all biochemical analyses. Nymphs from Szopienice had lower glutathione contents and lower glutathione-dependent enzyme activity in comparison with nymphs from the reference site. This was especially distinct in nymphs hatched from eggs laid by young females. The offspring of aging females from Olkusz, in terms of glutathione contents and glutathione reductase activities, revealed similar patterns to those from the reference site. For the remaining parameters, enzyme activity patterns in nymphs from Olkusz were similar to those of nymphs from Szopienice.

关键词： catalase diapause glutathione glutathione-dependent enzymes grasshoppers,heavy metals

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Transversal Instability for the Thermodiffusive Reaction-Diffusion System

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 871-882页

作者： michal KOWALCZYK Benoit PERTHAME Nicolas VAUCHELET Departamento de Ingenieria Matematica and Centro de Modelamiento Matem'atico(UMI CNRS 2807) Universidad de Chile Sorbonne Universités UPMC Univ Paris 06UMR 7598Laboratoire Jacques-Louis LionsF-75005ParisFrance CNRS UMR 7598Laboratoire Jacques-Louis LionsF-75005ParisFrance INRIA-Paris-Rocquencourt EPC MAMBADomaine de VoluceauBP10578153 Le Chesnay CedexFrance

The propagation of unstable interfaces is at the origin of remarkable patterns that are observed in various areas of science as chemical reactions, phase transitions, and growth of bacterial colonies. Since a scalar equation generates usually stable waves, the simplest mathematical description relies on two-by-two reaction-diffusion systems. The authors' interest is the extension of the Fisher/KPP equation to a two-species reaction which represents reactant concentration and temperature when used for flame propagation,and bacterial population and nutrient concentration when used in *** authors study circumstances in which instabilities can occur and in particular the effect of dimension. It is observed numerically that spherical waves can be unstable depending on the coefficients. A simpler mathematical framework is to study transversal instability, which means a one-dimensional wave propagating in two space ***, explicit analytical formulas give explicitely the range of paramaters for instability.

关键词： Traveling waves Stability analysis Reaction-diffusion equation Thermodiffusive system

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Passive Seismic Structure Imaging of a Coal Mine by Ambient Noise Seismic Interferometry on a Dense Array

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 37-39页

作者： GU Ning michal CHAMARCZUK GAO Ji michal MALINOWSKI ZHANG Haijiang Laboratory of Seismology and Physics of Earth’s Interior School of Earth and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China Institute of Geophysics Polish Academy of Science Warszawa 01-452Poland

Active source seismic method is generally used to image subsurface structures for resource exploration,including oil,gas and *** it can provide highresolution subsurface structures,due to some economic and environmental restrictions,it is not suitable in some *** recent 20 years,passive seismic survey based on ambient noise seismic interferometry(ANSI)has started to be widely used in imaging subsurface *** comparison,ANSI does not need active sources and can image subsurface structures at different depths as a lowcost alternative to active seismic exploration.

关键词： passive seismic imaging ambient noise interferometry coal mine body wave

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What do we know about biological nitrogen fixation in insects? Evidence and implications for the insect and the ecosystem

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Insect Science 2020年第3期27卷 392-403页

作者： Nitsan Bar-Shmuel Adi Behar michal Segoli Mitrani Department of Desert Ecology Jacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede Boqer CampusIsrael Kimron Veterinary Institute Department of ParasitologyBet DaganIsrael

Many insects feed on a low‐nitrogen diet,and the origin of their nitrogen supply is poorly *** has been hypothesized that some insects rely on nitrogen‐fixing bacteria(diazotrophs)to supplement their *** fixation by diazotrophs has been extensively studied and convincingly demonstrated in termites,while evidence for the occurrence and role of nitrogen fixation in the diet of other insects is less ***,we summarize the methods to detect nitrogen fixation in insects and review the available evidence for its occurrence(focusing on insects other than termites).We distinguish between three aspects of nitrogen fixation investigations:(i)detecting the presence of potential diazotrophs;(ii)detecting the activity of the nitrogen‐fixing enzyme;and(iii)detecting the assimilation of fixed nitrogen into the insect *** show that although evidence from investigations of the first aspect reveals ample opportunities for interactions with potential diazotrophs in a variety of insects,demonstrations of actual biological nitrogen fixation and the assimilation of fixed nitrogen are restricted to very few insect groups,including wood‐feeding beetles,fruit flies,leafcutter ants,and a wood *** then discuss potential implications for the insect's fitness and for the ecosystem as a *** suggest that combining these multiple approaches is crucial for the study of nitrogen fixation in insects,and argue that further demonstrations are desperately needed in order to determine the relative importance of diazotrophs for insect diet and fitness,as well as to evaluate their overall impact on the ecosystem.

关键词： biological nitrogen fixation diazotrophs gut microbiome insect diet

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Spin-preserving chiral photonic crystal mirror

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Light(Science & Applications) 2020年第1期9卷 1787-1798页

作者： Behrooz Semnani Jeremy Flannery Rubayet Al Maruf michal Bajcsy Institute for Quantum Computing(IQC) University of WaterlooWaterloo N2L3G1 ONCanada Department of Electrical&Computer Engineering University of WaterlooWaterloo N2L3G1 ONCanada Department of Physics and Astronomy University of WaterlooWaterloo N2L3G1 ONCanada

Chirality refers to a geometric phenomenon in which objects are not superimposable on their mirror *** made of nanoscale chiral elements can exhibit chiroptical effects,such as dichroism for left-and right-handed circularly polarized light,which makes these structures highly suitable for applications ranging from quantum information processing and quantum optics to circular dichroism spectroscopy and molecular *** the same time,strong chiroptical effects have been challenging to achieve even in synthetic optical media,and chiroptical effects for light with normal incidence have been speculated to be prohibited in thin,lossless quasi-two-dimensional ***,we report an experimental realization of a giant chiroptical effect in a thin monolithic photonic crystal *** conventional mirrors,our mirror selectively reflects only one spin state of light while preserving its handedness,with a near-unity level of circular *** operational principle of the photonic crystal mirror relies on guided-mode resonance(GMR)with a simultaneous excitation of leaky transverse electric(TE-like)and transverse magnetic(TM-like)Bloch modes in the photonic crystal *** modes are not reliant on the suppression of radiative losses through long-range destructive interference,and even small areas of the photonic crystal exhibit robust circular *** its simplicity,the mirror strongly outperforms earlier reported structures and,contrary to a prevailing notion,demonstrates that near-unity reflectivity contrast for opposite helicities is achievable in a quasi-two-dimensional structure.

关键词： mirror crystal circular

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NODAL O(h^4)-SUPERCONVERGENCE IN 3D BY AVERAGING PIECEWISE LINEAR,BILINEAR,AND TRILINEAR FE APPROXIMATIONS

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Journal of Computational Mathematics 2010年第1期28卷 1-10页

作者： Antti Hannukainen Sergey Korotov michal Krízek Institute of Mathematics Helsinki University of Technology Department of Mathematics Tampere University of Technology Institute of Mathematics Academy of Sciences

We construct and analyse a nodal O（h^4）-superconvergent FE scheme for approximating the Poisson equation with homogeneous boundary conditions in three-dimensional domains by means of piecewise trilinear functions. The scheme is based on averaging the equations that arise from FE approximations on uniform cubic, tetrahedral, and prismatic partitions. This approach presents a three-dimensional generalization of a two-dimensional averaging of linear and bilinear elements which also exhibits nodal O（h^4）-superconvergence （ultracon- vergence）. The obtained superconvergence result is illustrated by two numerical examples.

关键词： Higher order error estimates Tetrahedral and prismatic elements Supercon-vergence Averaging operators.

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Links Between HX-Groups and Hypergroups

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Algebra Colloquium 2021年第3期28卷 441-452页

作者： Irina Cristea michal Novák Babatunde Oluwaseun Onasanya Centre for Information Technologies and Applied Mathematics University of Nova Gorica Slovenia Faculty of Electrical Engineering and Communication Brno University of Technology Czech Republic Key Laboratory of Intelligent Information Processing and Control of Chongqing Municipal Institutions of Higher Education Chongqing Three Gorges University Chongqing 404000China Department of Mathematics University of IbadanNigeria

The concept of an HX-group is an upgrade of the concept of a group,in which a new operation is defined on the family of non-empty subsets of a *** this new support set together with the new operation is a group,then we call it an *** the other hand,a hyperoperation is a mapping having the same codomain as the operation of an HX-group,i.e.,the family of non-empty subsets of the initial set,but a different domain-the set *** could be(and was indeed)a source of confusion,which is clarified in this ***,HX-groups naturally lead to constructions of *** links between these two algebraic concepts are presented,with the aim of reviving the old notion of an HX-group in the current research on algebraic *** of such existing links and one newly established link are also discussed.

关键词： HX-group hyperstructure theory Chinese hypergroupoid EL-hyperstructure power set

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Past,present and future of industrial plantation forestry and implication on future timber harvesting technology

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Journal of Forestry Research 2020年第2期31卷 339-351页

作者： Andrew McEwan Enrico Marchi Raffaele Spinelli michal Brink Department of Agriculture Food and Forest SystemsFlorence UniversityVia San Bonaventura1350145 FlorenceItaly School of Natural Resource Management Nelson Mandela Metropolitan UniversityGeorge CampusGeorgeSouth Africa Consiglio Nazionale delle Ricerche Istituto per la BioEconomiaVia Madonna del Piano 10Sesto FiorentinoItaly Australian Forest Operations Research Alliance University of the Sunshine CoastLocked Bag 4Maroochydore DCQLD 4558Australia University of Pretoria Private Bag X20HatfieldPretoria 0028South Africa

Plantation forests are established,and expanding,to satisfy increasing global demand for timber *** societal values,such as safety,productivity,environmental,quality and social are influencing the plantation forestry *** is primarily driven through an ever increasing world population,which in turn influences the way nations view the value systems by which they *** people require more resources-also forest ***,the availability of information is influencing the pace of technological *** changes could result in a difference in the management of plantations that could affect the forest engineering systems of the *** review aimed to summarize the current status of plantation forests;summarize future developments and possible scenarios in forest plantation management for the various products;and assess whether these developments in a plantation environment could affect the harvesting systems *** influencing the form of plantations include the type and nature of the plantation owner;the change in demand for different and new forest products;climate change factors,including the use of biomass for energy,carbon sequestration and trading;ecosystem services and other products and services;and sustainability certification of forest *** impact and influence of these factors were summarised into a series of key drivers that will influence the technology used in harvesting machines,as well as the choice of harvesting machines,systems and *** drivers were the effect of variations in tree size,the expansion of plantation areas onto more difficult terrain,diversity in plantation design,increased attention towards site impacts and the increased use of biomass for *** information is provided regarding how the harvesting systems could be affected.

关键词： Plantations Forest products Biomass Harvesting system Mechanization Trends Technology

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Dextran-modified iron oxide nanoparticles

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China Particuology 2007年第1期5卷 162-168页

作者： Jií Hradil Alexander Pisarev michal Babi Daniel Hork Institute of Macromolecular Chemistry Academy of Sciences of the Czech Republic Heyrovsky Sq. 2 162 06 Prague Czech Republic

Dextran-modified iron oxide nanoparticles were prepared by precipitation of Fe（Ⅱ） and Fe（Ⅲ） salts with ammonium hydroxide by two methods. Iron oxide was precipitated either in the presence of dextran solution, or the dextran solution was added after precipitation. In the second method, the iron oxide particle size and size distribution could be controlled depending on the concentration of dextran in the solution. The nanoparticles were characterized by size-exclusion chromatography, transmission electron microscopy and dynamic light scattering. Optimal conditions for preparation of stable iron oxide colloid particles were determined, The dextran/iron oxide ratio 0-0,16 used in precipitation of iron salts can be recommended for synthesis of nanoparticles suitable for biomedical applications, as the colloid does not contain excess dextran and does not coagulate.

关键词： Iron oxide Nanoparticles Dextran Size-exclusion chromatography Particle size

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Molecular dynamics simulation on generalized stacking fault energies of FCC metals under preloading stress

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Chinese Physics B 2015年第8期24卷 586-593页

作者：张亮吕程 Tieu Kiet 赵星裴林清 michal Guillaume School of Mechanical Materials and Mechatronic Engineering University of Wollongong

Molecular dynamics(MD) simulations are performed to investigate the effects of stress on generalized stacking fault(GSF) energy of three fcc metals(Cu, Al, and Ni). The simulation model is deformed by uniaxial tension or compression in each of [111], [11-2], and [1-10] directions, respectively, before shifting the lattice to calculate the GSF curve. Simulation results show that the values of unstable stacking fault energy(γusf), stable stacking fault energy(γsf), and unstable twin fault energy(γutf) of the three elements can change with the preloaded tensile or compressive stress in different *** ratio of γsf/γusf, which is related to the energy barrier for full dislocation nucleation, and the ratio of γutf/γusf, which is related to the energy barrier for twinning formation are plotted each as a function of the preloading stress. The results of this study reveal that the stress state can change the energy barrier of defect nucleation in the crystal lattice, and thereby can play an important role in the deformation mechanism of nanocrystalline material.

关键词： molecular dynamics embeded atom method generalized stacking fault

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