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Phenology of high-arctic butterflies and their floral resources： Species-specific responses to climate change

Current Zoology 2014年第2期60卷 243-251页

作者： Toke T.HФYE Anne ESKILDSEN Rikke R. HANSEN Joseph J.BOWDEN Niels m.schmidt W.Daniel KISSLING Aarhus Institute of Advanced Studies Hoegh-Guldbergs Gade 6B bldgs. 1630-1632 DK-8000 Aarhus C Denmark Department ofBioscience Kalo Aarhus University Grenaivej 14 DK-8410 Ronde Denmark Arctic Research Centre Aarhus University C.F. Mollers Allé 8 bldg. 1110 DK-8000 Aarhus C Denmark Department of Bioscience Aarhus Aarhus University Ny Munkegade bldg. 1540 DK-8000 Aarhus C Denmark Department of Bioscience Aarhus University Frederiksborgvej 399 DK-4000 Roskilde Denmark Institute for Biodiversity and Ecosystem Dynamics (IBED) University of Amsterdam P.O. Box 94248 1090 GE AmsterdamThe Netherlands

Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtually absent. We examined butterfly specimens collected from yellow pitfall traps over 14 years （1996-2009） at Zackenberg in high-arctic, north-east Greenland. Specimens were previously sorted to the family level. We identified them to the species level and examined long-term species-specific phenological responses to recent summer wanning. Two species were rare in the samples （Polaris fritillary Boloria polaris and Arctic blue Plebejus glandon） and statistical analyses of phenological responses were therefore restricted to the two most abundant species （Arctic fritillary, B. chariclea and Northern clouded yellow Colias hecla）. Our analyses demonstrated a trend towards earlier flight seasons in B. chariclea, but not in C. hecla. The timing of onset, peak and end of the flight season in B. chariclea were closely related to snowmelt, July temperature and their interaction, whereas onset, peak and end of the flight season in C. hecla were only related to timing of snowmelt. The duration of the butterfly flight season was significantly positively related to the temporal overlap with floral resources in both butterfly species. We further demonstrate that yellow pitfall traps are a useful alternative to transect walks for butterfly recording in tundra habitats. more phenological studies of Arctic arthropods should be carded out at the species level and ideally be analysed in context with interacting species to assess how ongoing climate change will affect Arctic biodiversity in the near future [Current Zoology 60 （2）： 243-251, 2014].

关键词： Arctic Arthropod Flight period Greenland Pitfall trap Zackenberg

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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A NOTE ON A TRANSFERENCE THEOREm OF LINEAR FORmS

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Science China mathematics 1979年第3期 276-280页

作者： WOLFGANG m.schmidt,王元 Department of mathematics University of Colorado USA Institute of mathematics Academia Sinica

In this paper, a transference theorem of linear forms in diophantine approximation is proved. The proof of the theorem depends on a theorem of mahler.

关键词： A NOTE ON A TRANSFERENCE THEOREm OF LINEAR FORmS over

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Concise Synthesis of Lactococcus garvieae Lipoteichoic Acids Through an Additive-modulated Preactivation Protocol and the Immunological Studies

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CCS Chemistry 2024年第2期6卷 403-414页

作者： Tianlu Li Tong Li Yue Yang Haoru Zhuang Jianwu Lv Ning Zhou miaomiao Zhang Fengshan Wang Yiqun Geng Richard R.schmidt Peng Peng National Glycoengineering Research Center Shandong Key Laboratory of Carbohydrate Chemistry and GlycobiologyNMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate Based MedicineShandong UniversityQingdao 266237 State Key Laboratory of Bioactive Substance and Function of Natural medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050 Department of Chemistry University of KonstanzD-78457 Konstanz

Lipoteichoic acids(LTAs)are macroamphiphiles composed of alditol,lipid,phosphate,and carbohydrate *** to their inherent complexity,it is a severe challenge to access LTAs with structural integrity from natural sources for biological or immunological ***,we describe the first total synthesis of Lactococcus garvieae LTA(type II LTA),containing five distinct 1,2-cis gluco/galactopyranosidic linkages,via a novel additive-modulated O-glycosyl trichloroacetimidate preactivation glycosidation *** strategy features(1)high glycosidation yields and excellent 1,2-cis stereoselectivities independent of the donor anomeric configuration,(2)common and inexpensive reagents as promoters and additives,(3)application to standard glycosyl imidate donors without resorting to participating protection,and(4)general application to reactive and less reactive glycosyl ***,via the precise stereocontrolled construction of three galactopyranosidic and two glucopyranosidic bonds on a multigram scale,a series of structurally well-defined LTA molecules were successfully *** evaluation of these type II synthetic LTAs showed a structure–activity relationship in the stimulation of a proinflammatory response.

关键词： 1,2-cis glycosidation stereoselectivity lipoteichoic acid total synthesis additive-modulated trichloroacetimidate glycosidation immune response

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Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： Semiconductor TiO_(2) Rare earths Congo red methylene blue Solar spectrum Photodegradation

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肩关节造影术的方法和影象对比

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放射学实践 1989年第2期4卷 44-52页

作者： m.schmidt 王■ Institut für Rntgen-Diagnostik Krankenhaus Moabit 同济医科大学附属协和医院

用等渗性非离子型造影剂进行的肩关节造影术与早期应用的造影剂相比,其并发症的发生率明显减少。这一方法对诊断的价值很大。

关键词：肩关节造影术造影剂 X线诊断

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语法惊异——论语言戏剧化的认知情感机制

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当代语言学 2024年第3期26卷 317-335页

作者：井茁俄勒冈大学东亚语言文学系

在日常生活中,戏剧化的语言呈现令人惊的事件、表达强烈的情感体验。那么戏剧化的语言有哪些特征?其戏剧性又从何而来呢?继“戏剧化语言”这一概念提出以来,汉语语言学界对相关现象的研究不断深入,不仅分析了语言戏剧性在汉语词汇句法... 详细信息

在日常生活中,戏剧化的语言呈现令人惊的事件、表达强烈的情感体验。那么戏剧化的语言有哪些特征?其戏剧性又从何而来呢?继“戏剧化语言”这一概念提出以来,汉语语言学界对相关现象的研究不断深入,不仅分析了语言戏剧性在汉语词汇句法上的表现,而且从戏曲审美和戏剧语言的角度发掘、论述了汉语特有的戏剧化模式与手段。这些研究成果进一步深化拓展了语言主观性研究的理论视野。同时,戏剧化语言作为一个理论构建还有待进一步界定和锤炼。本文拟从信息的情感认知层面探讨语言的戏剧性和戏剧化机制,提出“语法惊异”这一理论构建,即创造性的语法逾矩所产生的惊异情感认知体验在语言体系中的凝结、更新、再创造。我们认为,语法惊异作为戏剧性语言的心理基础,在理论上补充了先前提出的以认知显著性和情感表达力为标志的戏剧化语言命题。文章以汉语、英语和德语为例,从语法惊异的视角阐释语言戏剧性的具身性,并探讨语言类型学特征对语法惊异编码的制约。

关键词：戏剧化语法惊异主观构建具身性类型学

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Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABAD m.H.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** Hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

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Enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m Setodeh Kheirabady m K Tavassoly m Rafeie E Ghasemian Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Department of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. more interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

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