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Conspecific cues and breeding territory selection in Whinchat on abandoned fields

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Avian Research 2024年第4期15卷 445-450页

作者： dmitry Shitikov Tatiana Vaytina Polina Lebedyanskaya Moscow Pedagogical State University 129164Kibalchicha Str.6/3MoscowRussia

Many bird species use social information to guide territory *** species in different habitats may use both pre-breeding and post-breeding conspecific *** agricultural fields are of particular interest for studies of conspecific attraction because the ephemeral nature of the habitat suggests territory search just before breeding,but high predation pressure suggests the use of performance-based conspecific *** investigated whether post-breeding or pre-breeding social cues affect Whinchat(Saxicola rubetra)abundance at the territorial scale during a two-year experiment in abandoned *** assigned 27 experimental plots(3.14 ha)to one of three treatments:post-breeding treatment,pre-breeding treatment and silent *** conducted playback experiments with fledgling calls(evidence of past reproductive success)during the post-breeding period and male songs(evidence of conspecific presence)during the pre-breeding *** estimated the difference in Whinchat abundance in two consecutive years and tested whether this value differed between treatment and control *** observed a slight increase(0.67±0.29 pairs per plot)in Whinchat abundance in the post-breeding treatment plots and no significant changes in the pre-breeding(-0.22±0.32 pairs per plot)and control(-0.22±0.22 pairs per plot)*** results suggest that Whinchats do not use conspecific acoustic cues during the pre-breeding period and provide limited evidence for the use of fledgling calls as conspecific cues in the post-breeding period.

关键词： Abandoned fields Conspecific attraction Fledgling calls Playback experiment Whinchat

Theoretical models for irradiation hardening and embrittlement in nuclear structural materials:a review and perspective

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Acta Mechanica Sinica 2020年第2期36卷 397-411页

作者： Xiazi Xiao dmitry Terentyev Haijian Chu Huiling Duan Department of Mechanics School of Civil EngineeringCentral South UniversityChangsha 410075China Structural Materials Group Institute of Nuclear Materials ScienceSCK-CEN2400 MolBelgium Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China State Key Laboratory for Turbulence and Complex System Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China CAPT HEDPS and IFSA CollaborativeInnovation Center of MoEBIC-ESATPeking UniversityBeijing 100871China

The study of irradiation hardening and embrittlement is critically important for the development of next-generation structural materials tolerant to neutron irradiation,and could dramatically affect the approach to the design of components for advanced nuclear *** addition,a growing interest is observed in the field of research and development of irradiation-resistant *** review aims to provide an overview of the theoretical development related to irradiation hardening and embrittlement at moderate irradiation conditions achieved in recent years,which can help extend our fundamental knowledge on nuclear structural *** a general introduction to the irradiation effects on metallic materials,recent research progress covering theoretical modelling is summarized for different types of structural *** fundamental mechanisms are elucidated within a wide range of temporal and spatial *** review closes with the current understanding of irradiation hardening and embrittlement,and puts some perspectives deserving further study.

关键词： Irradiation hardening Irradiation embrittlement Theoretical models Fundamental mechanisms

Laboratory investigation of a new scale inhibitor for preventing calcium carbonate precipitation in oil reservoirs and production equipment

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Petroleum Science 2016年第2期13卷 320-327页

作者： Azizollah Khormali dmitry G.Petrakov Department of Oil and Gas Field Development and Operation Oil and Gas FacultyNational Mineral Resources University(Mining University)

The formation of mineral scale is a complex problem during the oilfield operations. Scale inhibitors are widely used to prevent salt precipitation within reservoirs, in downhole equipment, and in production facilities. The scale inhibitors not only must have high effectiveness to prevent scale formation, but also have good adsorption- desorption characteristics, which determine the operation duration of the scale inhibitors. This work is focused on the development of a new scale inhibitor for preventing cal- cium carbonate formation in three different synthetic for- mation waters. Scale inhibition efficiency, optical density of the solution, induction time of calcium carbonate for- mation, corrosion activity, and adsorption-desorption ability were investigated for the developed scale inhibitor. The optimum concentration of hydrochloric acid in the inhibitor was determined by surface tension measurement on the boundary layer between oil and the aqueous scale inhibitor solution. The results show that the optimum mass percentage of 5 % hydrochloric acid solution in the inhi- bitor was in the range of 8 % to 10 %. The new scale inhibitor had high efficiency at a concentration of 30 mg/L. The results indicate that the induction period for calcium carbonate nucleation in the presence of the new inhibitor was about 3.5 times longer than the value in the absence of the inhibitors. During the desorption process at reservoir conditions, the number of pore volumes injected into the carbonate core for the developed inhibitor was significantly greater than the volume of a tested industrial inhibitor, showing better adsorption/desorption capacity.

关键词： Scale inhibitor Desorption Corrosionactivity - Precipitation Optical density

Russian school of the theory and geometry of gearing： Its origin and golden period （1935-1975）

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Frontiers of Mechanical Engineering 2016年第1期11卷 44-59页

作者： dmitry BABICHEV Sergey LAGUTIN Natalya BARMINA Department of Applied Mechanics Tyumen State Oil and Gas University Tyumen 625000 Russia Electrostal Plant of Heavy Machine Engineering Electrostal City144012 Russia Institute of Mechanics Kalashnikov Izhevsk State Technical Universitylzhevsk 426069 Russia

During the second half of the twentieth century, Soviet scientists were among the world leaders in the theory and geometry of gearing or the theoretical fundamentals of designing gears and gear-cutting tools. The authors of the current paper review works related to the development of the theory of gearing （TG） written in Russian from the mid-1930s to the present. Overall, the review covers more than 400 publications of nearly 200 authors （among more than 1000 studied works）. This review involves some works on gear strength and accuracy to attract more experts. This paper presents a short list of works from the seventeenth century to the nineteenth century and discusses the basic concepts of the TG. This paper also includes a review of more than 160 papers in Russian for the period of 1935-1975, which is the ＂golden age＂ of the TG. The main features and achievements during this period are also considered. The distinctive feature of this review is the use of diagrams that visually present TG experts and the dates and themes of their published works. The diagrams also show the following aspects： 1） The most popular and important themes in a specific period, 2） the most important publications on the themes of interest to readers, and 3） the direction of the works and scope of interests of every researcher.

关键词： theory of gearing (TG) gear geometry,generating surface gear synthesis gear analysis

Comparison of linear and nonlinear extreme wave statistics

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Acta Oceanologica Sinica 2016年第5期35卷 99-105页

作者： dmitry Chalikov ALEXANDER V.Babanin Swinburne University of Technology Victoria 3122 Australia P.P. Shirshov Institute of Oceanology Saint-Petersburg 199053 Russia

An extremely large（＂freak＂） wave is a typical though rare phenomenon observed in the sea. Special theories（for example, the modulation instability theory） were developed to explain mechanics and appearance of freak waves as a result of nonlinear wave-wave interactions. In this paper, it is demonstrated that the freak wave appearance can be also explained by superposition of linear modes with the realistic spectrum. The integral probability of trough-to-crest waves is calculated by two methods： the first one is based on the results of the numerical simulation of a wave field evolution performed with one-dimensional and two-dimensional nonlinear *** second method is based on calculation of the same probability over the ensembles of wave fields constructed as a superposition of linear waves with random phases and the spectrum similar to that used in the nonlinear simulations. It is shown that the integral probabilities for nonlinear and linear cases are of the same order of values

关键词： freak waves numerical modeling probability of linear and nonlinear waves ensemble modeling

Probing the endoplasmic reticulummitochondria interaction in Alzheimer's disease:searching far and wide

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Neural Regeneration Research 2024年第10期19卷 2103-2104页

作者： Giulia Dematteis Laura Tapella dmitry Lim Department of Pharmaceutical Sciences Universitàdel Piemonte Orientale“Amedeo Avogadro”NovaraItaly

Alzheimer's disease(AD)is the most frequent,form of dementia in elderly people and is an incurable disease with an exponentially growing number of *** deposition of amyloid-β(Aβ)plaques and intraneuronal formation o... 详细信息

关键词： Alzheimer Aβ reticulum

Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

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Frontiers of Structural and Civil Engineering 2019年第1期13卷 190-200页

作者： Eric N.LANDIS Roman KRAVCHUK dmitry LOSHKOV Department of Civil &Environmental Engineering University of MaineOronoME 04469USA

Split-cylinder fracture of fiber-reinforced ultra-high-performance concrete (UHPC)was examined using two complementary techniques:X-ray computed tomography (CT)and acoustic emission (AE).Fifty-mm-diameter specimens of two different fiber types were scanned both before and after load *** the CT images,fiber orientation was evaluated to establish optimum and pessimum specimen orientations,at which fibers would have maximum and minimum effect,*** expected,fiber orientation affected both the peak load and the toughness of the specimen,with the optimum toughness being between 20% and 30%higher than the *** AE energy was also affected *** CT scans of the specimens were used to measure internal damage. Damage was quantified in terms of internal energy dissipation due to both matrix cracking and fiber pullout by using calibration measurements for *** results showed that fiber pullout was the dominant energy dissipation mechanism;however,the sum of the internal energy dissipation measured amounted to only 60% of the total energy dissipated by the specimens as measured by the net work of *** is postulated that localized compaction of the UHPC matrix as well as internal friction between fractured fragments makes up the balance of internal energy dissipation.

关键词： ultra-high-performance concrete concrete fracture X-ray computed tomography acoustic emission

Ecological Niche Modelling Reveals the Peculiarities of Ecological Disjunction Between Two Sympatric Racerunners in Kazakhstan:Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867)

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Asian Herpetological Research 2023年第2期14卷 123-137页

作者： Marina A.CHIRIKOVA dmitry V.MALAKHOV Institute of Zoology Committee of Scientific Ministry of Science and Higher EducationAl-Farabi 93 AkademgorodokAlmaty 050060Kazakhstan

The ecological-niche models for two sympatric species,Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867),reveal evidence of spatial and temporal disjunction in the actual niches of both *** lineolata demonstrates a wide range of adaptations and,at the same time,has a greater need for winter precipitation and minimal temperature than *** explanations for the thermal diversity of both species are *** variables(monthly temperatures,monthly solar radiation,etc.)are traditionally important for ectotherm ***,as many as half of the key variables in both species are related to different aspects of environmental water balance(precipitation,air humidity,vapor pressure).There are several ways in which moisture may impact the lizard’s life *** humidity is related to soil temperature and may be important during winter *** summer,soil humidity may support successful *** during the warm months is a key factor in maintaining the moisture content of the *** winter,snow cover provides a better thermal balance of the soil’s top layers where winter shelters are *** niche modeling(ENM)is an interdisciplinary approach combining the geographical,climatic,ecological,and biological aspects of the wellbeing of *** interdisciplinary approach lifts biological studies onto a new,integrative level,providing a comprehensive view on species biology and answering the questions that might not be answered if the traditional methods for studying animals were used alone.

关键词： ecology Kazakhstan niche modelling racerunners species distribution

Unsteady bio-fluid dynamics in flying and swimming

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Acta Mechanica Sinica 2017年第4期33卷 663-684页

作者： Hao Liu dmitry Kolomenskiy Toshiyuki Nakata Gen Li Graduate School of Engineering Chiba University 1-33Yayoi-cho Inage-ku Chiba Japan Shanghai-Jiao Tong University and Chiba UniversityInternational Cooperative Research Centre (SJTU-CU ICRC) Shanghai 200240 China

Flying and swimming in nature present sophisticated and exciting ventures in biomimetics, which seeks sustainable solutions and solves practical problems by emulating nature＇s time-tested patterns, functions, and strategies. Bio-fluids in insect and bird flight, as well as in fish swimming are highly dynamic and unsteady; however, they have been studied mostly with a focus on the phenomena associated with a body or wings moving in a steady flow. Characterized by unsteady wing flapping and body undulation, fluid-structure interactions, flexible wings and bodies, turbulent environments, and complex maneuver, bio-fluid dynamics normally have challenges associated with low Reynolds number regime and high unsteadiness in modeling and analysis of flow physics. In this article, we review and highlight recent advances in unsteady bio-fluid dynamics in terms of leading-edge vortices, passive mechanisms in flexible wings and hinges, flapping flight in unsteady environments, and micro-structured aerodynamics in flapping flight, as well as undulatory swimming, flapping-fin hydrodynamics, body–fin interac-tion, C-start and maneuvering, swimming in turbulence,collective swimming, and micro-structured hydrodynamics in swimming. We further give a perspective outlook on future challenges and tasks of several key issues of the field.

关键词： swimming wings unsteady turbulence hydrodynamics turbulent body kinematics vortex street