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The role of male contest competition over mates in speciation

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Current Zoology 2012年第3期58卷 493-509页

作者： Anna QVARnSTROM niclas VALLIn Andreas RUDH Animal Ecology/Department of Ecology and Genetics Evolutionary Biology Centre Uppsala University Norbyv~gen 18DSE-752 36 Uppsala Sweden

Research on the role of sexual selection in the speciation process largely focuses on the diversifying role of mate choice. In particular, much attention has been drawn to the fact that population divergence in mate choice and in the male traits subject to choice directly can lead to assortative mating. However, male contest competition over mates also constitutes an important mechanism of sexual selection. We review recent empirical studies and argue that sexual selection through male contest competition can affect speciation in ways other than mate choice. For example, biases in aggression towards similar competitors can lead to disruptive and negative frequency-dependent selection on the traits used in contest competition in a similar way as competition for other types of limited resources. Moreover, male contest abilities often trade-off against other abilities such as parasite resistance, protection against predators and general stress tolerance. Populations experiencing different ecological condi- tions should therefore quickly diverge non-randomly in a number of traits including male contest abilities. In resource based breeding systems, a feedback loop between competitive ability and habitat use may lead to further population divergence. We discuss how population divergence in traits used in male contest competition can lead to the build up of reproductive isolation through a number of different pathways. Our main conclusion is that the role of male contest competition in speciation remains largely scientifically unexplored [Current Zoology 58 （3）： 493-509, 2012].

关键词： Male-male competition Sexual selection Speciation Resource based breeding systems Contest competition Population divergence Reproductive isolation

Direct GHG emissions from a pilot scale MBR-process treating municipal wastewater

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Advances in Climate Change Research 2022年第1期13卷 138-145页

作者： Christian BARESEL Jingjing YAnG niclas BORnOLD Kare TJUS Linda KAnDERS Klara WESTLInG IVL Swedish Environmental Research Institute AB Valhallavagen 81Stockholm 10031Sweden

To evaluate direct greenhouse gas emissions from Membrane Biological Reactor(MBR),measurements of nitrous oxide(n_(2)O)and methane(CH_(4))were made at a pilot-scale MBR treating municipal wastewater Measurements were conducted during two campaigns with some changes in processes,*** a pre-aeration tank in the second measurement,different distributions of aeration in the treatment line,not the same wastewater inflow rate,two types of ultrafiltration *** was found that about 0.004% and 0.07% of the total ammonium loads were emitted as n_(2)O,CH_(4) emissions were 0.026% and 0.12% of incoming TOC(0.008% and 0.04% of incoming COD)in 2014 and *** obtained n_(2)O emission values were relatively *** study suggested that a high aeration at the beginning of the treatment line may result in significantly high emissions of both n_(2)O and CH_(4).A significant change in aeration in the membrane ultrafiltration tank did not have the same *** MBR process is known for high quality effluent but have been questioned due to its higher carbon footprint due to energy *** study gave a reference case about direct GHG emissions from MBR process and provide information for the further evaluation of MBR processes.

关键词： Greenhouse gases(GHGs) nitrous oxide(n_(2)O) Methane(CH_(4)) Membrane biological reactor(MBR)

A Virtual Prototyping Approach for Development of PMSM on Real‑Time Platforms: A Case Study on Temperature Sensitivity

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Automotive Innovation 2022年第3期5卷 285-298页

作者： René Scheer Yannick Bergheim Simon Aleff Daniel Heintges niclas Rahner Rafael Gries Jakob Andert Teaching and Research Area Mechatronics in Mobile Propulsion RWTH Aachen UniversityForckenbeckstr.4Aachen 52074Germany DEnSO Automotive Deutschland GmbH Friedrich‑List‑Allee 42Wegberg 41844Germany

This paper presents a comprehensive evaluation of system interactions in a battery electric vehicle caused by temperature sensitivity of permanent magnet synchronous machines(PMSM).An analytical model of a PMSM considering iron losses and thermal impact is implemented on a field programmable gate array suitable for hardware-in-the-loop *** the presented virtual prototyping approach,different machine characteristics defined by the design are used to parameterize the analytical *** investigated temperature effect is understood as an interacting influence between machine character-istics and control,which are investigated in terms of torque generation,voltage utilization and efficiency under closed-loop condition in a vehicle *** particular,using a surface permanent magnet rotor and an interior permanent magnet rotor,the performance of both machine designs is analyzed by varying temperature-adjusted feedforward control strategies on the basis of a driving cycle from a *** comparison shows that the machine design with surface-mounted mag-nets is associated with higher temperature *** this case,the temperature consideration in the feedforward control provides a14%loss reduction in closed-loop vehicle test *** can be summarized that the electromagnetic torque is less sensitive to a temperature variation with increasing *** presented development approach demonstrates the impact of interactions in electric powertrains without the need of real prototypes.

关键词： FPGA PMSM Iron loss FEM Spatial harmonics RT-MIL Virtual prototyping Frontloading Closed-

Vertical integration of microchips by magnetic assembly and edge wire bonding

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Microsystems & nanoengineering 2020年第1期6卷 1233-1246页

作者： Federico Ribet Xiaojing Wang Miku Laakso Simone Pagliano Frank niklaus niclas Roxhed Goran Stemme Division of Micro and nanosystems School of Electrical Engineering and Computer ScienceKTH Royal Institute of TechnologyMalvinas vag 1010044 StockholmSweden

The out-of-plane integration of microfabricated planar microchips into functional three-dimensional(3D)devices is a challenge in various emerging MEMS applications such as advanced biosensors and flow ***,no conventional approach currently provides a versatile solution to vertically assemble sensitive or fragile microchips into a separate receiving substrate and to create electrical *** this study,we present a method to realize vertical magnetic-field-assisted assembly of discrete silicon microchips into a target receiving substrate and subsequent electrical contacting of the microchips by edge wire bonding,to create interconnections between the receiving substrate and the vertically oriented *** assembly is achieved by combining carefully designed microchip geometries for shape matching and striped patterns of the ferromagnetic material(nickel)on the backside of the microchips,enabling controlled vertical lifting directionality independently of the microchip’s aspect *** form electrical connections between the receiving substrate and a vertically assembled microchip,featuring standard metallic contact electrodes only on its frontside,an edge wire bonding process was developed to realize ball bonds on the top sidewall of the vertically placed *** top sidewall features silicon trenches in correspondence to the frontside electrodes,which induce deformation of the free air balls and result in both mechanical ball bond fixation and around-the-edge metallic *** edge wire bonds are realized at room temperature and show minimal contact resistance(nd excellent mechanical robustness(>168 mn in pull tests).In our approach,the microchips and the receiving substrate are independently manufactured using standard silicon micromachining processes and materials,with a subsequent heterogeneous integration of the ***,this integration technology potentially enables emerging MEMS applications that requ

关键词： bonding Vertical magnetic

no association between brain size and male sexual behavior in the guppy

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Current Zoology 2015年第2期61卷 265-273页

作者： Alberto CORRAL-LOPEZ Simon ECKERSTROM-LIEDHOLM Wouter VAn DER BIJL Alexander KOTRSCHAL niclas KOLM Department of Zoology/Ethology Stockholm University Svante Arrhenius v~ig 18B. SE-10691 Stockholm Sweden

Animal behavior is remarkably variable at all taxonomic levels. Over the last decades, research on animal behavior has focused on understanding ultimate processes. Yet, it has progressively become more evident that to fully understand beha- vioral variation, ultimate explanations need to be complemented with proximate ones. In particular, the mechanisms generating variation in sexual behavior remain an open question. Variation in aspects of brain morphology has been suggested as a plausible mechanism underlying this variation. However, our knowledge of this potential association is based almost exclusively on com- parative analyses. Experimental studies are needed to establish causality and bridge the gap between micro- and macroevolutio- nary mechanisms concerning the link between brain and sexual behavior. We used male guppies that had been artificially selected for large or small relative brain size to study this association. We paired males with females and scored the full known set of male and female sexual behaviors described in guppies. We found several previously demonstrated associations between male traits, male behavior and female behavior. Females responded more strongly towards males that courted more and males with more orange coloration. Also, larger males and males with less conspicuous coloration attempted more coerced copulations. However, courting, frequency of coerced copulation attempts, total intensity of sexual behavior, and female response did not differ between large- and small-brained males. Our data suggest that relative brain size is an unlikely mechanism underlying variation in sexual behavior of the male guppy. We discuss these findings in the context of the conditions under which relative brain size might affect male sexual behavior .

关键词： Brain size Brain morphology Sexual behavior Guppy Artificial selection Behavioral mechanisms

Physio-chemical interaction of Ethylene-Vinyl Acetate copolymer on bonding ability in the cementing material used for oil and gas well

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Petroleum Research 2022年第3期7卷 341-349页

作者： Sai Teja Lanka niclas Galih Anak Moses Raja Rajeswary Suppiah Belladonna Troxylon Maulianda Universiti Teknologi PETROnAS Seri IskandarPerak32610Malaysia PTPERTAMInA(Persero) Jakarta10110Indonesia

Effective bond of cement sheath to casing or formation depends on higher tensile strength and lower young's modulus which are a measure of its ability to withstand deformation under load without *** work utilized Ethylene Vinyl Acetate(EVA)redispersible polymer powder as additive in the class G cement to characterize bonding *** strength was measured for samples cured at 90°C for 3 days,whereas compressive strength was measured for samples cured at 120°C for 1 day and 3 days under atmospheric *** results showed that,with the addition of beyond 10% by weight of cement(BWOC)of polymer,not only tensile strength was improved,but also reduced young's *** of EVA additive beyond 10% BWOC showed significant benefit of flexibility in the cement ***(Fourier Transform Infrared Spectroscopy)indicated that presence of high VA(Vinyl Acetate)has no effect on polymerization of Silicates,which shows it does not hider in the formation of C–S–H *** of chemical bond augmented with longer curing time and increased polymer content,as seen in O–H stretching vibration at 3434 cm^(−1) and from Carboxylate anion at 1571 cm^(−1) to confirm on *** Intrusion porosimeter(MIP)showed significant reduction in fraction of mesopore sizes within the cement matrix,with the polymer addition.

关键词： Well cementing EVA-Modified cement Flexibility Infrared spectroscopy Pore size distribution

Giant mid-IR resonant coupling to molecular vibrations in sub-nm gaps of plasmonic multilayer metafilms

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Light(Science & Applications) 2022年第10期11卷 2476-2484页

作者： Rakesh Arul David-Benjamin Grys Rohit Chikkaraddy niclas S.Mueller Angelos Xomalis Ermanno Miele Tijmen Geuser Jeremy J.Baumberg nanoPhotonics Centre Cavendish LaboratoryDepartment of PhysicsJJ Thompson AvenueUniversity of CambridgeCambridge CB30HEUnited Kingdom The Faraday Institution Quad OneHarwell Science and Innovation CampusDidcotUnited Kingdom

nanomaterials capable of confining light are desirable for enhancing spectroscopies such as Raman scattering,infrared absorption,and nonlinear optical *** superlattices have shown the ability to host collective resonances in the mid-infrared,but require stringent fabrication processes to create well-ordered ***,we demonstrate how short-range-ordered Au nanoparticle multilayers on a mirror,self-assembled by a sub-nm molecular spacer,support collective plasmon-polariton resonances in the visible and infrared,continuously tunable beyond 11 pm by simply varying the nanoparticle size and number of *** resulting molecule-plasmon system approaches vibrational strong coupling,and displays giant Fano dip strengths,SEIRA enhancement factors~106,light-matter coupling strengths g~100 cm-1,Purcell factors~106,and mode volume compression factors~*** collectiive plasmon-polariton mode is highly robust to nanoparticle vacancy disorder and is sustained by the consistent gap size defined by the molecular *** disorder efficiently couples light into the gaps between the multilayers and mirror,enabling Raman and infrared sensing of sub-picolitre sample volumes.

关键词： coupling collective mirror

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气候变化--对钢铁工业的最大挑战

钢铁 2003年第Z1期38卷 8-9页

作者： niclas Svenningsen （United nations Environment Programme）

　　钢铁是长期以来对社会和发展起主要作用的基础材料.基础结构、运输、集装箱、电力生产和输送、商品制作甚至金融系统都以不同形式在使用着钢铁产品.近数十年已有几个预言,指出钢铁作为社会的主要材料已快结束.替代材料,如合成材料... 详细信息

　　钢铁是长期以来对社会和发展起主要作用的基础材料.基础结构、运输、集装箱、电力生产和输送、商品制作甚至金融系统都以不同形式在使用着钢铁产品.近数十年已有几个预言,指出钢铁作为社会的主要材料已快结束.替代材料,如合成材料、塑料、陶瓷和玻璃,已发展有新的性能,在许多应用方面可以取代钢铁.但同一时间,优秀的钢铁产品设计扩大了其应用范围,涉及钢铁产品应用开发的投资在继续扩大.因此,尽管有相反的预言,但在近期的将来,没有理由去期待钢铁应用会衰落下去.　　……

关键词：气候变化钢铁工业钢铁产品应用开发替代材料应用范围金融系统基础结构基础材料合成材料电力生产产品设计集装箱制作运输性能投资陶瓷塑料衰落

Integrating MEMS and ICs

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Microsystems & nanoengineering 2015年第1期1卷 165-180页

作者： Andreas C.Fischer Fredrik Forsberg Martin Lapisa Simon J.Bleiker Göran Stemme niclas Roxhed Frank niklaus Department of Micro and nanosystems School of Electrical EngineeringKTH Royal Institute of TechnologySE-10044 StockholmSweden

The majority of microelectromechanical system(MEMS)devices must be combined with integrated circuits(ICs)for operation in larger electronic *** MEMS transducers sense or control physical,optical or chemical quantities,ICs typically provide functionalities related to the signals of these transducers,such as analog-to-digital conversion,amplification,filtering and information processing as well as communication between the MEMS transducer and the outside ***,the vast majority of commercial MEMS products,such as accelerometers,gyroscopes and micro-mirror arrays,are integrated and packaged together with *** are a variety of possible methods of integrating and packaging MEMS and IC components,and the technology of choice strongly depends on the device,the field of application and the commercial *** this review paper,traditional as well as innovative and emerging approaches to MEMS and IC integration are *** include approaches based on the hybrid integration of multiple chips(multi-chip solutions)as well as system-on-chip solutions based on wafer-level monolithic integration and heterogeneous integration *** are important technological building blocks for the‘More-Than-Moore’paradigm described in the International Technology Roadmap for *** this paper,the various approaches are categorized in a coherent manner,their merits are discussed,and suitable application areas and implementations are critically *** implications of the different MEMS and IC integration approaches for packaging,testing and final system costs are reviewed.

关键词： cofabrication platforms integrated circuits(ICs) microelectromechanical system(MEMS) More-Than-Moore multichip modules(MCMs) system-in-package(SiP) system-on-chip(SoC) three-dimensional(3D)heterogeneous integration