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Fruit fly courtship： The female perspective

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Current Zoology 2015年第6期61卷 1008-1014页

作者： Reuven DUKAS andrew SCOTT Animal Behaviour Group Department of Psychology Neuroscience and Behaviour McMaster University 1280 Main Street West Hamilton Ontario L8S 4K1 Canada

Research on fruit fly courtship has mostly focused on males＇ behavioral repertoire whereas females have been as- sumed to respond by either rejecting or accepting males. In many fruit fly species including Drosophila melanogaster, however, mating typically follows an extended period of courtship, which provides ample opportunities for females to inform males about their likelihood of mating. Our experiments indeed revealed that sexually immature females in both D. melanogasterand D. si- mulans showed responses to conspecific males that were distinct from those of sexually mature females. Furthermore, females＇ responses to conspecifie males were different from their responses to heterospecific males. Our data indicate that females＇ beha- vioral repertoire early in courtship can inform males about their probability of mating if they persist in courting. We hypothesize （i） that males can rely on behavioral feedback from females for optimally allocating their courtship efforts towards distinct female classes, （ii） that males may learn to modulate their courtship behavior based on specific feedback from females, and （iii） that fe- males may learn to alter their behavior towards distinct types of males in order to elicit the desired male response. Overall, we suggest that, although little explored, female behavior determines the dynamics of courtship and mating and can thus influence sexual selection and incipient speciation .

关键词： Courtship Female behavior Fruit flies Learning Mate choice Speciation

Testing decreasing variabililty of cockroach forewings through time using four Recent species： Blattella germanica, Polyphaga aegyptiaca, Shelfordella lateralis and Blaberus craniifer, with implications for the study of fossil cockroach forewings

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Insect Science 2012年第2期19卷 129-142页

作者： andrew J. Ross Department of Natural Sciences National Museums Scotland Edinburgh UK

Vrsansky, （2000） considered there is decreasing variability in the forewings of cockroaches through time, based on a study of fossil and Recent species. This study tests his theory, based on a study of four Recent species of cockroaches： Blattella germanica （Blattellidae）, Polyphaga aegyptiaca （Polyphagidae）, Shelfordella lateralis （Blattidae） and Blaberus craniifer （Blaberidae）. The new results, based on the coefficient of variation （CV） of the number of veins, indicate that Recent species can be more variable than fossil species and therefore do not support the theory. The results also show that at least 30 complete wings of the same species are required for a reliable CV value that is compa- rable between species.

关键词： Blaberidae Blattellidae Blattidae cockroach Polyphagidae variation

Advancing the Disaster and Development Paradigm

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International Journal of Disaster Risk Science 2018年第4期9卷 486-495页

作者： andrew E.Collins Department of Geography and Environmental Sciences /Disaster and Development Network (DDN) Northumbria University

Consolidation of disaster and development studies as an integrated field of action research that influences policy has proved to be fundamental to global disaster risk reduction, sustainable development, climate change, and humanitarian agreements. However, challenges in achieving targets, such as those of the Sendai Framework for Disaster Risk Reduction 2015–2030 and the Sustainable Development Goals, requires further advances of the disaster and development paradigm underpinning these aspirations. This article presents perspectives that grew primarily from local action research, particularly research carried out with marginalized and highly at-risk groups of people in Southern Africa and South *** fronts from these findings emphasize disaster and development risk assessment opportunities that consolidate earlier ideas and extend understanding of disaster and development-related risk intervention options. These acknowledge severe shortcomings in disaster risk reduction progress while including greater use of hope as an active ingredient. This process of paradigm exploration remains fundamental to achieving disaster risk reduction, sustainable development, and associated policy objectives. The analysis presented here reiterates earlier groundings in people-centric perspectives, emphasizing social relations and systems of meaning as essential active ingredients for challenging power structures, technology, education, and human behavior. The analysis proposes some consequent thematic fronts for increased investment. These includeinvesting in early buildup of well-being before a disaster,better living with uncertainty, and overcoming the barriers to desired disaster and development outcomes. The article is intended to contribute to an ever-evolving paradigm of disaster and development risk that requires impetus from personal and collective values beyond calculations of disaster and development.

关键词： Disaster and development paradigm Disaster risk reduction Disaster risk management Local action research

Seeing invisible objects with intelligent optics IsaacNape&andrewForbes

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Light(Science & Applications) 2024年第10期13卷 1995-1996页

作者： Isaac Nape andrew Forbes School of Physics University of the WitwatersrandJohannesburgSouth Africa

Transparent objects are invisible to traditional cameras because they can only detect intensity fluctuations,necessitating the need for interferometry followed by computationally intensive digital image *** it is shown that the necessary transformations can be performed optically by combining machine learning and diffractive optics,for a direct in-situ measurement of transparent objects with conventional cameras.

关键词： optics visible interferometry

Large quantum alphabets with a tiny footprint

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Light(Science & Applications) 2024年第9期13卷 1701-1703页

作者： Fazilah Nothlawala andrew Forbes School of Physics University of the WitwatersrandJohannesburgSouth Africa

High-dimensional quantum states are known to offer advantages over their two-dimensional qubit counterparts,but their preparation and manipulation has been bulky and ***,quantum state control has been demonstrated on-chip with a~1μm2 footprint and nm-scale features,producing up to eight-dimensional quantum states and ushering in a new route to large quantum information encoding on a small footprint.

关键词： quantum states dimensional

Exceptionally high strain hardening via two-dimensional atomic scale faulting

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Science China Materials 2023年第12期66卷 4897-4898页

作者： andrew Godfrey Xiaoxu Huang Laboratory of Advanced Materials School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China International Joint Laboratory for Light Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400044China

Strain hardening is a characteristic and important property of metals whereby they are strengthened by the introduction of lattice defects during plastic *** general,a high strain hardening ability is desired,both to ensure the safety of metal components under load and to enable high ductility,allowing the formation of complex *** underlying mechanisms of strain hardening have been extensively studied and are related to an increase in the density of linear lattice defects,i.e.,dislocations,and to the interaction between these defects during the evolution of three-dimensional dislocation structures[1±3].Coarse-grained(CG)metals generally show the highest strain hardening and the best tensile ductility due to the more abundant space for storage of dislocations in various forms of patterning.

关键词： strain ductility dimensional

Digital switched hydraulics

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Frontiers of Mechanical Engineering 2018年第2期13卷 225-231页

作者： Min PAN andrew PLUMMER Centre for Power Transmission and Motion Control Department of Mechanical Engineering University of Bath BA2 7AY Bath UK

This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems （SIHSs）. The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.

关键词： digital hydraulics switched inertance hydraulic systems energy efficiency high-speed switching valve fluid-borne noise

Strong Laws of Large Numbers for Double Sums of Banach Space Valued Random Elements

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Acta Mathematica Sinica,English Series 2019年第5期35卷 583-596页

作者： Robert PARKER andrew ROSALSKY Department of Biostatistics University of Florida Department of Statistics University of Florida

For a double array {V_(m,n), m ≥ 1, n ≥ 1} of independent, mean 0 random elements in a real separable Rademacher type p(1 ≤ p ≤ 2) Banach space and an increasing double array {b_(m,n), m ≥1, n ≥ 1} of positive constants, the limit law ■ and in L_p as m∨n→∞ is shown to hold if ■ This strong law of large numbers provides a complete characterization of Rademacher type p Banach spaces. Results of this form are also established when 0 < p ≤ 1 where no independence or mean 0 conditions are placed on the random elements and without any geometric conditions placed on the underlying Banach space.

关键词： Real separable Banach space double array of independent random elements strong law of large numbers almost sure convergence Rademacher type p Banach space convergence in Lp

Mshpy23:a user-friendly,parameterized model of magnetosheath conditions

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Earth and Planetary Physics 2024年第1期8卷 89-104页

作者： Jaewoong Jung Hyunju Connor andrew Dimmock Steve Sembay andrew Read Jan Soucek NASA Goddard Space Flight Center GreenbeltMDUSA Department of Astronomy University of MarylandCollege ParkMDUSA Swedish Institude of Space Physics UppsalaSweden University of Leicester LeicesterUK Institute of Atmospheric Physics Academy of Sciences of the Czech Republic

Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind−Magnetosphere−Ionosphere Link Explorer(SMILE)will observe magnetosheath and its boundary motion in soft X-rays for understanding magnetopause reconnection modes under various solar wind conditions after their respective launches in 2024 and *** conditions,namely,plasma density,velocity,and temperature,are key parameters for predicting and analyzing soft X-ray images from the LEXI and SMILE *** developed a userfriendly model of magnetosheath that parameterizes number density,velocity,temperature,and magnetic field by utilizing the global Magnetohydrodynamics(MHD)model as well as the pre-existing gas-dynamic and analytic *** this parameterized magnetosheath model,scientists can easily reconstruct expected soft X-ray images and utilize them for analysis of observed images of LEXI and SMILE without simulating the complicated global magnetosphere ***,we created an MHD-based magnetosheath model by running a total of 14 OpenGGCM global MHD simulations under 7 solar wind densities(1,5,10,15,20,25,and 30 cm)and 2 interplanetary magnetic field Bz components(±4 nT),and then parameterizing the results in new magnetosheath *** compared the magnetosheath model result with THEMIS statistical data and it showed good agreement with a weighted Pearson correlation coefficient greater than 0.77,especially for plasma density and plasma ***,we compiled a suite of magnetosheath models incorporating previous magnetosheath models(gas-dynamic,analytic),and did two case studies to test the *** MHD-based model was comparable to or better than the previous models while providing self-consistency among the magnetosheath ***,we constructed a tool to calculate a soft X-ray image from any given vantage point,which can support the planning and data analysis of the aforementioned LEXI and SMILE missions.A release of the code has been uploaded to a Git

关键词： magnetosheath python modeling