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Spider odors induce stoichiometric changes in fruit fly Drosophila melanogaster

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Current Zoology 2021年第1期67卷 127-129页

作者： Ronalds KRAMS Tatj.na KRAMA Maris MUNKEVICS Sarah eichler David M.BUTLER Linda DOBKEVICA Priit j.ERS j.rge CONTRERAS-GARDUNO j.nina DAUKSTE Indrikis A.KRAMS Plant Health Estonian University of Life SciencesTartu 51006Estonia Department of Biotechnology Daugavpils UniversityDaugavpils 5401Latvia Institute of Ecology and Earth Sciences University of TartuTartu 51010Estonia Department of Zoology and Animal Ecology Faculty of BiologyUniversity of LatviaRiga 1004Latvia Department of Biological Sciences Kent State UniversityOhioSalem 4460USA Department of Plant Sciences University of TennesseeKnoxville 37996-4561USA Department of Environmental Science Faculty of Geography and Earth SciencesUniversity of LatviaRiga 1004Latvia Department of General and Microbial Biochemistry University of TartuTartu 51010Estonia Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Institute of Food Safety Animal Health and Environment BIORRiga 1076Latvia Department of Psychology University of TennesseeKnoxville 37996-4561USA

Animal senses and signals are amazingly diverse,and the maj.r modalities by which animals acquire sensory input from their environments are sound,light,vibration,and chemical *** mainly rely on visual,nociceptive,and olfactory cues to discriminate between rewards and *** has been shown that the visual and olfactory cues of predators substantially affect the adult phenotype in Drosophila melanogaster(Krams et al.2016),a prominent animal model for biological research.

关键词： melanogaster cues Drosophila

Comparison of the Overall CO_(2) Emissions of Different Powertrain Systems Depending on the Energy Sector Emissions

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同济大学学报（自然科学版） 2024年第S1期52卷 46-50页

作者： Tobias STOLL hans-j.rgen BERNER AndréCASAL KULZER Research Institute for Automotive Engineering and Powertrain Systems Stuttgart(FKFS) 70569 StuttgartGermany Institute of Automotive Engineering(IFS) University of Stuttgart70569 StuttgartGermany

A circular and sustainable economy for the private transport sector requires a holistic view of the emitted CO_(2) *** at the energy supplied to the vehicle in terms of a circular economy leads to *** remaining energy sources or forms are renewable electric energy,green hydrogen and renewable fuels.A holistic view of the CO_(2) emissions of these energy sources and forms and the resulting powertrain technologies must take into account all cradle-to-grave emissions for both the vehicle and the energy *** order to compare the different forms of energy,the three most relevant forms of powertrain technology are considered and a configuration is chosen that allows for an appropriate *** this purpose,data from the FVV proj.ct“Powertrain 2040”are used[1]and combined with research data on the energy supply chain for passenger *** three comparable powertrain configurations are a battery electric vehicle,a fuel cell electric vehicle and an internal combustion engine hybrid vehicle fueled with electric ***,the three selected powertrain configurations are presented in terms of their performance,weight,technology and other characteristics.A comparative analysis is carried out for different CO_(2) emissions of the electricity *** electricity mix is used for both the production of the vehicle and the *** results are presented in the form of cradle-to-wheel emissions,which consider the total CO_(2) emissions of the vehicle over its life ***,the results are analyzed and discussed to determine which powertrain technology fits best into which energy sector CO_(2) emissions window.

关键词： vehicles energy supply power system carbon emission

Relationship between rock macro-and micro-properties and wellbore breakout type

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Underground Space 2021年第1期6卷 62-75页

作者： Hossein Rahmati Alireza Nouri Dave Chan hans Vaziri University of Alberta AlbertaCanada BP America Inc. HoustonUSA

This study numerically investigates the effect of material micro-and macro-parameters on the failure mechanisms and geometry of a wellbore *** analysis of the borehole breakout is essential in addressing wellbore stability,well completion,and sand production *** three-dimensional discrete element method(DEM)was used in the *** numerical tool was used in numerical model simulations of drilling through sandstone in cubic samples at the laboratory scale subj.cted to pre-existing far-field ***,a series of triaxial testing simulations were performed to relate the micromechanical parameters to the macromechanical material *** results showed that the geometry of the breakout is affected,among the material micro-parameters,by the particle contact modulus,bond normal and shear strengths,particle crushing strength,and particle size ***,it was found that the macro-parameters including Young’s modulus,friction and dilation angles,and uniaxial compression strength(UCS)also affect the type of breakout.

关键词： Borehole breakout Numerical simulation Material properties

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FKFS和IFS氢能车辆驱动系统研究

同济大学学报（自然科学版） 2024年第S1期52卷 210-214页

作者： Anne BEYER hans-j.rgen BERNER AndréCASAL KULZER 斯图加特大学汽车工程学院(IFS) 德国斯图加特70569 斯图加特汽车工程与车辆发动机研究所(FKFS) 德国斯图加特70569

本文介绍氢气在交通运输领域的相关应用,以氢气直喷(H2-DI)内燃机的开发过程为例,阐述斯图加特汽车工程与车辆发动机研究所(FKFS)和斯图加特大学汽车工程学院(IFS)的研究工作。在单缸乘用车发动机试验台上研究氢气高压直喷特性(FVV项目)... 详细信息

本文介绍氢气在交通运输领域的相关应用,以氢气直喷(H2-DI)内燃机的开发过程为例,阐述斯图加特汽车工程与车辆发动机研究所(FKFS)和斯图加特大学汽车工程学院(IFS)的研究工作。在单缸乘用车发动机试验台上研究氢气高压直喷特性(FVV项目),目标是实现氢气发动机在当量混合条件下稳定运行,从而以较低的增压需求输出较大功率。当发动机在高负荷条件下工作时,当量混合比更容易导致爆震现象。为了防止末端气体发生预反应,喷射氢气将在点火上止点(TDCF)前不久开始,随后由火花塞点燃。喷射持续时间以及喷射的最大质量流量都将在不同程度上影响燃烧的持续时间。此外,本研究还探讨了氢气燃烧过程中所存在的问题,如较高的氮氧化合物排放量,以及未燃氢气进入排气系统等。

关键词：氢气内燃机直喷当量燃烧

Palynostratigraphy of the Zorritas Formation, Antofagasta region, Chile： Insights on the Devonian]Carboniferous boundary in western Gondwana

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Geoscience Frontiers 2017年第3期8卷 493-506页

作者： Claudia V. Rubinstein Elodie Petus hans Niemeyer IANIGLA CCT-CONICET Mendoza Av. Ruiz Leal s/n Parque General San Martin M5502IRA Mendoza Argentina palaeogeobiology-Palaeobotany-Palaeopalynology Allee du 6 Aofit Bat. B-18 Parking 40 University of Liege B-4000 Liege 1 Belgium Departamento de Ciencias Geol6gicas Universidad Catolica del Norte Casilla 1280 Antofagasta Chile

The Middle Member of the Zorritas Formation in the Antofagasta region of northern Chile, yielded terrestrial and marine palynomorph assemblages which span the Devonian/Carboniferous boundary. The assemblages show a clear predominance of terrestrial palynomorphs with 70 miospore species, 18 marine phytoplankton species, two non-marine algae and one chitinozoan species, all coming from 15 productive levels. Palynomorphs are poorly preserved and most of them are reworked. Three palyno- logical associations are recognized based on miospores. These are assigned to the Tournaisian-Visean, Tournaisian and probable latest Famennian. Age assignments are discussed in the frame of the spore zonal schemes established for Euramerica and western Gondwana. The stratigraphical distribution of spores allows the identification of the probable position of the Devonian/Carboniferous boundary within the Zorritas Formation. This system boundary is proposed for the first time in Palaeozoic sedimentary rocks of northern Chile. The presence of Gondwanan typical miospore species indicates affinities with this palaeocontinent even though the Tournaisian and Tournaisian-Viseao miospore associations sup- port the cosmopolitanism already suggested for the early Carboniferous flora. The significant number of reworked palynomorphs together with the sedimentological analysis of the studied sections, suggest that these deposits were severely impacted by the climatic change and maj.r sea level fluctuations. Similar conditions were recorded in coeval western Gondwana basins.

关键词： Miospores Phytoplankton Devonian/Carboniferous boundary Western Gondwana Chile

Pacing and predictors of performance during cross-country skiing races:A systematic review

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j.urnal of Sport and Health Science 2018年第4期7卷 381-393页

作者： Thomas Stogg Barbara Pellegrini hans-Christer Holmberg Department of Sport and Exercise Science University of SalzburgHallein/Rif 5400Austria CeRiSM Research Centre＂Sport Mountainand Health＂Rovereto 36068Italy Department of Neuroscience Biomedicine and MovementUniversity of VeronaVerona 37100Italy Swedish Winter Sports Research Centre Mid Sweden UniversityOstersund 83128Sweden School of Sport Sciences UiT Arctic University of NorwayTroms（）9037Norway School of Kinesiology University of British ColumbiaVancouverBC V6T 121Canada Department of Physiology and Pharmacology Karolinska InstitutetStockhol 17177Sweden Corresponding author.E-mail address：thomas.stoeggl@sbg.ac.at

Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subj.ct headings and keywords. Only original research articles published in peerreviewed j.urnals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single d

关键词： Classic style Competition Cycle characteristics Positive pacing Skating

Study of the degradation behavior and the biocompatibility of Mg-0.8Ca alloy for orthopedic implant applications

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j.urnal of Magnesium and Alloys 2019年第2期7卷 249-257页

作者： Aya Mohamed Ahmed MEl-Aziz hans-Georg Breitinger Materials Engineering Department German University in Cairo(GUC)11835 New CairoEgypt Department of Biochemistry German University in Cairo(GUC)11835 New CairoEgypt

Mg-Ca alloys have recently attracted great attention towards the research in the field of orthopedic biodegradable *** study presents an in vitro degradation assessment of Mg-0.8Ca(0.8 wt.%of Ca)alloy in Hank’s balanced salt solution(HBSS).Immersion,hydrogen evolution and electrochemical behavior was studied as well as the cytotoxicity of the degradation *** and phase composition of the corrosion products were studied using SEM,EDX and XRD *** in HBSS resulted in the formation of the needle-shaped carbonated hydroxyapatite which was similar to the biological apatite in the human *** kinetics showed that Mg-0.8Ca alloy had approximately 3-fold faster degradation rate than the pure Mg(1.08±0.38 mm/year for Mg-0.8Ca and 0.35±0.17 mm/year for pure Mg),as observed in two independent ***,pure Mg and Mg-0.8Ca alloy were biocompatible,generating no cytotoxic degradation products against human-derived HEK 293 ***,the Mg-0.8Ca alloy was found to be a promising biodegradable implant in terms of bioactivity and compatibility with human cell *** on the application of the implant and the estimated healing time of the bone,the desired degradation rate of an implant can be controlled by the Mg-Ca composition of such alloys.

关键词： Mg-Ca alloys Biodegradability Orthopedic implants Biocompatibility Toxicity Hydroxyapatite

等通道转角挤压Al-Mg-Si铝合金的动态时效特性和力学性能

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材料研究学报 2016年第10期30卷 721-730页

作者：刘满平韦江涛李毅超江家威姜奎 hans j.Roven 江苏大学材料科学与工程学院江苏省高端结构材料重点实验室镇江212013 挪威科技大学材料科学与工程学院挪威特隆赫姆7491

在不同温度对固溶处理后的6061铝合金进行等通道转角挤压(ECAP),以实现动态时效处理。采用X射线衍射(XRD)、差示扫描量热法(DSC)、透射电镜(TEM)及拉伸测试,研究了6061 Al-Mg-Si铝合金的动态时效行为和力学性能。DSC分析结果表明,合金在... 详细信息

在不同温度对固溶处理后的6061铝合金进行等通道转角挤压(ECAP),以实现动态时效处理。采用X射线衍射(XRD)、差示扫描量热法(DSC)、透射电镜(TEM)及拉伸测试,研究了6061 Al-Mg-Si铝合金的动态时效行为和力学性能。DSC分析结果表明,合金在ECAP过程中发生动态时效析出。XRD,DSC和TEM的分析结果均表明,合金在动态时效过程中生成了大量的位错和β″析出相。在不同温度进行ECAP动态时效,制备出几种高韧性(均匀伸长率大于10%)和高强度兼备的6061铝合金。ECAP动态时效铝合金的最高抗拉强度和屈服强度,分别为450 MPa和425 MPa。ECAP铝合金的高强高韧,可归因于ECAP后极细的β''析出相和高密度位错的交互作用。

关键词：金属材料等通道转角挤压大塑性变形 Al-Mg-Si铝合金动态时效力学性能强韧性

Computational fluid dynamics modeling of abutment scour under steady current using the level set method

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International j.urnal of Sediment Research 2020年第4期35卷 355-364页

作者： Mohammad Saud Afzal hans Bihs Lalit Kumar Department of Civil Engineering Indian Institute of Technology Department of Civil and Environmental Engineering Norwegian University of Science and Technology

The scour and deposition pattern around an abutment under constant discharge condition is calculated using a three dimensional(3D) Computational Fluid Dynamics(CFD) *** Reynolds-Averaged Navier Stokes(RANS) equations are solved in three dimensions using a CFD *** Level Set Method(LSM) is used for calculation of both free surface and bed *** two-equation turbulence model(k-ε and k-ω) is used to calculate the eddy viscosity in the RANS *** pressure term in the RANS equations on a staggered grid is modeled using the Chorin’s proj.ction *** 5th order Weighted Essentially Non-Oscillatory(WENO) scheme discretizes the convective term of the RANS *** Kovacs and Parker and Dey formulations are used for the reduction in bed shear stress on the sloping *** model also used the sandslide algorithm which limits bed shear stress reduction during the erosion *** numerical model solution is validated against experimental results collected at the Politecnico di Milano,Milan,*** r,the numerical model is tested for perfo rmance by varying the grid sizes and key parameters like the space and time discretization *** effect of varying bed porosity has been ***,the free surface is well represented in a realistic manner and bed topography is well predicted using the Level Set Method(LSM).

关键词： Sediment transport Computational Fluid Dynamics(CFD) Reynolds-Averaged Navier Stokes(RANS) Level Set Method(LSM) Weighted Essentially Non-Oscillatory(WENO) Total Variation Diminishing(TVD)