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New observations-with older ones reviewed-on mass migrations in millipedes based on a recent outbreak on Hachijojima(Izu Islands) of the polydesmid diplopod(Chamberlinius hualienensis,Wang 1956):Nothing appears to make much sense

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Zoological Research 2015年第3期36卷 119-132页

作者： victor Benno MEYER-ROCHOW Research Institute of Luminous Organisms Department of Biology (El?inmuseo) University of Oulu

Mass aggregations and migrations of millipedes despite numerous attempts to find causes for their occurrences are still an enigma. They have been reported from both southern and northern hemisphere countries, from highlands and lowlands of both tropical and temperate regions and they can involve species belonging to the orders Julida and Spirobolida, Polydesmida and Glomerida. According to the main suggestions put forward in the past, mass occurrences in Diplopoda occur：（1） because of a lack of food and a population increase beyond sustainable levels;（2） for the purpose of reproduction and in order to locate suitable oviposition sites;（3） to find overwintering or aestivation sites;（4） because of habitat disruption and changes in the local environment;（5） as a consequence of weather conditions the year（or winter and spring） before. A recent outbreak（November 2014） of a mass migration of the polydesmid Chamberlinius hualienensis Wang 1956 on the Japanese Izu Island of Hachijojima 300 km to the south of Tokyo gave this author an opportunity to review the existing literature on millipede mass migrations and to carry out additional observations on the phenomenon in the field as well as the laboratory. Hitherto unreported heavy infestations with phoretic deutonymphs of the mite Histiostoma sp. as well as dense populations of internal rhabditid nematodes（Oscheius cf. necromena and an unidentified species of the genus Fictor）, suggest that infestations of this kind could be necromenic and either have been a contributing factor for the mass migration or been a consequence of so manyindividuals occurring together at close proximity. It is concluded that mass migrations and aggregations in millipedes do not have one common cause, but represent phenomena that often are seasonally recurring events and appear identical in their outcome, but which have evolved as responses to different causes in different millipede taxa and therefore need to be examined on a case-to-case basis.

关键词： Myriapoda Spawning migration Aggregation behaviour Diplopod commensals and parasites

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TiO_(2)/WO_(3)heterogeneous structures prepared by electrospinning and sintering steps:Characterization and analysis of the impedance variation to humidity

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Journal of Advanced Ceramics 2019年第2期8卷 238-246页

作者： Evando S.ARAuJO victor N.S.LEAO Research Group on Electrospinning and Nanotechnology Applications(GPEA-Nano) Department of Materials ScienceUniversidade Federal do Vale do Sao Francisco

Relative humidity(RH) is a critical environmental variable for transportation and storage of products and for the quality guarantee of several other production processes and services. Heterogeneous structures prepared from the selective semiconductor oxides may improve the sensitivity to humidity due to the better electronic and surface properties, when compared to pristine oxides. This work shows an alternative fabrication route for producing titanium dioxide/tungsten trioxide(TiO2/WO3) heterogeneous structures(by electrospinning and sintering) for potential application on the RH detection. The microstructural properties of the materials were analyzed by scanning electron microscopy(SEM), energy dispersive X-ray analysis(EDS), X-ray diffraction, and Raman spectroscopy. The electrical characterization of the structures was performed by electrical impedance spectroscopy in RH range of 10%–100%. Results indicated a p-to n-type conduction transition at around 30%–40% RH for all tested settings. The analysis of the impedance signature to humidity showed that the amount of fiber layers on the electrode and working temperature are important parameters to improve the humidity sensing of the TiO2/WO3 systems.

关键词： electrospinning heterogeneous structures preparation relative humidity semiconductors

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Some problerns in adsorption and calorimetric studies of the steps of catalytic processes

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Journal of Natural Gas Chemistry 2004年第3期13卷 123-147页

作者： victor E.Ostrovskii Karpov Institute of Physical Chemistry ul. Vorontsovo Pole 10 Moscow 105064 Russiarincipal side factors as well as technical and procedural peculiarities capable of distorting the results of measurements of adsorbed and desorbed amounts of falsifying the nature of the processes proceeding in the systems under study and of promoting artifacts in calorimetric and other studies of gas chemisorption on powders are considered. Modified techniques and procedures allowing the elimination of sources of side phenomena and artifacts and freeing traditional glass static adsorption apparatuses and experimental procedures from undesirable factors and peculiarities are proposed. Some available chemisorption and calorimetric data representing artifacts and also some data that are not artifacts but due to imperfections of chemisorption techniques show up as artifacts are presented and discussed. Several applications of the improved techniques and procedures to calorimetric and adsorption studies of the steps of catalytic processes proceeding on the basis of natural gas and of products of its processing are presented and discussed.

Principal side factors as well as technical and procedural peculiarities capable of distorting the results of measurements of adsorbed and desorbed amounts, of falsifying the nature of the processes proceeding in the systems under study, and of promoting artifacts in calorimetric and other studies of gas chemisorption on powders are considered. Modified techniques and procedures allowing the elimination of sources of side phenomena and artifacts and freeing traditional glass static adsorption apparatuses and experimental procedures from undesirable factors and peculiarities are proposed. Some available chemisorption and calorimetric data representing artifacts and also some data that are not artifacts but, due to imperfections of chemisorption techniques, show up as artifacts are presented and discussed. Several applications of the improved techniques and procedures to calorimetric and adsorption studies of the steps of catalytic processes proceeding on the basis of natural gas and of products of its processing are presented and discussed.

关键词： adsorption techniques and procedures adsorption and calorimetric artifacts calorimetric and chemisorption techniques chemisorption heats catalytic mechanisms chemisorption mechanisms heats of adsorption.

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Positive and negative streamers in air and nitrogen in a sharply inhomogeneous electric field under conditions of runaway electron generation

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High Voltage 2023年第3期8卷 527-537页

作者： Dmitry Beloplotov victor Tarasenko Dmitry Sorokin Cheng Zhang Tao Shao Institute of High Current Electronics Siberian Branch of the Russian Academy of ScienceTomskRussia Beijing International S&T Cooperation Base for Plasma Science and Energy Conversion Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina

The development of positive and negative streamers in a point-to-plane gap filled with air and nitrogen at various pressures(50-200 kPa)and voltages(8-25 kV)was studied.A four-channel intensified charge-coupled device(ICCD)and a streak-camera were *** parameters were measured with high resolution(10 GHz).An original method of measuring a displacement current caused by a streamer was *** was expected,positive streamer branches in nitrogen at low voltages and/or elevated pressures while a large-diameter streamer is formed in ***,at high voltages or negative polarity,the large-diameter streamer is formed both in nitrogen and air in the entire pressure *** was found that runaway electrons(REs)are generated in the very first picoseconds of gas ionisation near the pointed *** was assumed that REs can be generated near the pointed anode and produce bremsstrahlung radiation due to a sharply inhomogeneous distribution of electrical *** was found that in the final stage of negative streamer development in air and nitrogen,the gas between the streamer front and the opposite electrode is ionised almost simultaneously in the entire volume when the streamer diameter is almost equal to the interelectrode gap.

关键词： sharply inhomogeneous electrode

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Molecular mechanisms of NMDA receptor-mediated excitotoxicity:implications for neuroprotective therapeutics for stroke

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Neural Regeneration Research 2016年第11期11卷 1752-1753页

作者： victor Li Yu Tian Wang Djavad Mowafaghian Centre for Brain Health and Department of Medicine Vancouver Coastal Health Research InstituteUniversity of British Columbia Vancouver

Excitotoxicity is a process observed in many disease states by which an excessive synaptic excitation causes neuronal death, and is thought to be triggered by the extracellular accumulation of the excitatory neurotransmitter glutamate, which binds and activates ionotropic N-methyl-D-aspartate glutamatergic receptors （NMDARs） in the brain. Normally, NMDARs mediate calcium entry into the cell to regulate physiological processes such as synaptic plasticity and memory,

关键词： NMDAR Molecular mechanisms of NMDA receptor-mediated excitotoxicity

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Evaluation of different Krylov subspace methods for simulation of the water faucet problem

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Nuclear Science and Techniques 2021年第5期32卷 1-16页

作者： Hong-Yang Wei Kevin Briggs victor Quintanilla Yi-Tung Chen Department of Mechanical Engineering University of NevadaLas VegasNV 89154USA

In this study,a one-dimensional two-phase flow four-equation model was developed to simulate the water faucet *** performance of six different Krylov subspace methods,namely the generalized minimal residual(GMRES),transpose-free quasi-minimal residual,quasi-minimal residual,conjugate gradient squared,biconjugate gradient stabilized,and biconjugate gradient,was evaluated with and without the application of an incomplete LU(ILU)factorization preconditioner for solving the water faucet *** simulation results indicate that using the ILU preconditioner with the Krylov subspace methods produces better convergence performance than that without the ILU *** the GMRES demonstrated an acceptable convergence performance under the Krylov subspace methods without the *** velocity and pressure distribution in the water faucet problem could be determined using the Krylov subspace methods with an ILU preconditioner,while GMRES could determine it without the need for a ***,there are significant advantages of using an ILU preconditioner with the GMRES in terms of *** different Krylov subspace methods showed similar performance in terms of computational efficiency under the application of the ILU preconditioner.

关键词： Water faucet problem Krylov subspace methods ILU preconditioner

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Seamless morphing trailing edge flaps for UAS-S45 using high-fidelity aerodynamic optimization

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Chinese Journal of Aeronautics 2024年第2期37卷 12-29页

作者： Mir Hossein NEGAHBAN Musavir BASHIR victor TRAISNEL Ruxandra Mihaela BOTEZ LARCASE Laboratory of Applied Research in Active Controls Avionics and AeroservoelasticityEcole de Technologie SuperieureUniversite du QuebecMontreal H3C1K3Canada

The seamless trailing edge morphing flap is investigated using a high-fidelity steady-state aerodynamic shape optimization to determine its optimum configuration for different flight conditions,including climb,cruise,and gliding descent.A comparative study is also conducted between a wing equipped with morphing flap and a wing with conventional hinged *** optimization is performed by specifying a certain objective function and the flight performance goal for each flight *** the climb rate,extending the flight range and endurance in cruise,and decreasing the descend rate,are the flight performance goals covered in this *** optimum configurations were found for the morphing wing by determining the optimum morphing flap deflection for each flight condition,based on its objective function,each of which performed better than that of the baseline *** was shown that by using optimum configuration for the morphing wing in climb condition,the required power could be reduced by up to 3.8%and climb rate increases by 6.13%.The comparative study also revealed that the morphing wing enhances aerodynamic efficiency by up to 17.8%and extends the laminar ***,the optimum configuration for the gliding descent brought about a 43%reduction in the descent rate.

关键词： Seamless morphing trailing edge flap Aerodynamic optimization Gradient-based optimiza-tion Climb flight condition Gliding descent Flight range Endurance

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Controlling cooperativity of a metastable open system coupled weakly to a noisy environment

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Chinese Physics B 2015年第2期24卷 501-512页

作者： victor I.Teslenko Oleksiy L.Kapitanchuk Zhao Yang Bogolyubov Institute for Theoretical Physics National Academy of Sciences of Ukraine Division of Materials Science Nanyang Technological University

The notion of cooperativity comprises a specific characteristic of a multipartite system concerning its ability to demonstrate a sigmoidal-type response of varying sensitivities to input stimuli in transitions between states under controlled *** a statistical physics viewpoint,in this work we attempt to describe the cooperativity by the stability of a metastable open system with respect to *** treat the evolution of a system weakly coupled to the environment in a kinetic framework,we consider two fluctuating energy levels of different dimensionalities,initial population of one level,reversible transitions of population between the levels,and irreversible depopulation of another *** average is made over level fluctuations and environment vibrations so that an inter-level transition rate can be obtained accounting for the influences of external control on level position and *** is found that the cooperativity of the two-level system is bounded approximately between 0.736 and unity,with the lower bound indicating worsening system stability.

关键词： metastable open system nonstationary kinetic processes irreversibility energy fluctuations

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Growth performance,haematology,serum biochemistry and meat quality characteristics of Japanese quail(Coturnix coturnix japonica)fed canola meal-based diets

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Animal Nutrition 2018年第1期4卷 37-43页

作者： Caven M.Mnisi victor Mlambo Department of Animal Science School of Agricultural SciencesFaculty of AgricultureScience and TechnologyNorth-West University Food Security and Safety Niche Area Faculty of AgricultureScience and TechnologyNorth-West University

The present study investigated the effect of partial replacement of soybean meal(Glycine max) with canola meal(CM)(Brassica napus) on the growth performance,haematology,serum biochemistry and meat quality characteristics of female Japanese quails in a 35-day feeding *** hundred and forty6-week-old quails 158.28 ± 11.919 g were randomly allocated to 5 isonitrogenous and isoenergetic experimental diets: control diet(CM0; with no CM inclusion); CM0 with 2.5%(CM25),5.0%(CM50),12.5%(CM125) and 17.5%(CM175) soybean meal replaced with *** weekly gain(AWG) and feed conversion efficiency(FCE) were ***,serum biochemistry,carcass traits and meat quality parameters were determined at *** fed CM175 had the lowest(P 0.05) on cooking losses and peak positive force of quail *** was concluded that CM can replace soybean in quail diets up to 12.5% without compromising growth performance,health and quality of *** levels beyond 12.5% promoted poor voluntary feed intake and thus may require feed additives to enhance utilization.

关键词： Japanese quail Haematology Meat Feed intake Canola meal

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Stability of a Viscous Liquid Film in a Rotating Cylindrical Cavity under Angular Vibrations

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Fluid Dynamics & Materials Processing 2024年第12期20卷 2693-2707页

作者： victor Kozlov Alsu Zimasova Nikolai Kozlov Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia Institut de Mécanique des Fluides de Toulouse Toulouse INPToulouse31400France

The behavior of a viscous liquid film on the wall of a rapidly rotating cylinder subjected to angular vibrations is experimentally *** cavity is filled with an immiscible low-viscosity liquid of lower *** the absence of vibrations,the high viscosity liquid covers the inner surface of the cylinder with a relatively thin axisymmetric film;the low-viscosity liquid is located in the cavity *** is found that with an increase in the amplitude of rotational vibrations,the axisymmetric interphase boundary loses *** azimuthally periodic 2D“frozen wave”appears on the film surface in a threshold *** is shown that the frozen wave excitation is associated with the oscillatory Kelvin—Helmholtz instability,and the stability threshold depends on a vibrational *** new vibrational effects in rotating cavities are studied accordingly:the stability(critical value of vibrational parameter)grows with decreasing the contrast in liquids viscosity;the rotation(the Coriolis force)stabilizes the interface–the critical value of vibrational parameter grows with the dimensionless rotation rate,the threshold is characterized by the product of the aforementioned vibrational parameter and the dimensionless rotation rate to some *** discovered phenomena can be useful for vibrational control of interfaces in many technological processes,especially in the field of materials science.

关键词： Rotation oscillations immiscible fluids interface viscosity contrast “frozen wave”instability

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