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Light correcting light with nonlinear optics

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Advanced Photonics 2024年第2期6卷 41-49页

作者： Sachleen Singh Bereneice Sephton Wagner Tavares Buono Vincenzo D'Ambrosio Thomas konrad Andrew Forbes University of the Witwatersrand School of Physics Università degli studi di Napoli “Federico Ⅱ” Dipartimento di Fisica “E.Pancini” University of Kwa Zulu-Natal School of Chemistry and Physics

Structured light, where complex optical fields are tailored in all their degrees of freedom, has become highly topical of late, advanced by a sophisticated toolkit comprising both linear and nonlinear *** undesired structure from light is far less developed, leveraging mostly on inverting the distortion,e.g., with adaptive optics or the inverse transmission matrix of a complex channel, both requiring that the distortion be fully characterized through appropriate measurement. We show that distortions in spatially structured light can be corrected through difference-frequency generation in a nonlinear crystal without any need for the distortion to be known. We demonstrate the versatility of our approach using a wide range of aberrations and structured light modes, including higher-order orbital angular momentum(OAm) beams,showing excellent recovery of the original undistorted field. To highlight the efficacy of this process, we deploy the system in a prepare-and-measure communications link with OAm, showing minimal cross talk even when the transmission channel is highly aberrated, and outline how the approach could be extended to alternative experimental modalities and nonlinear processes. Our demonstration of light-correcting light without the need for measurement opens an approach to measurement-free error correction for classical and quantum structured light, with direct applications in imaging, sensing, and communication.

关键词： phase conjugation aberration correction orbital angular momentum nonlinear optics

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技术革新和世界范围的销售

世界制造技术与装备市场 1995年第3期 E006-E010页

作者： konrad mcke 张世莹

每两年一度的德国汉诺威国际展览会,显示了谨慎而乐观的形势,令人感觉到整个机器制造行业出现经济增长的势头。

关键词：机器制造工业技术革新展望

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The Silk roads: phylogeography of Central Asian dice snakes (Serpentes: Natricidae) shaped by rivers in deserts and mountain valleys

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Current Zoology 2024年第2期70卷 150-162页

作者： Daniel Jablonski konrad mebert Rafaqat masroor Evgeniy Simonov Oleg Kukushkin Timur Abduraupov Sylvia Hofmann Department of Zoology Comenius University in BratislavaBratislavaSlovakia Global Biology BirrSwitzerland Pakistan museum of Natural History ShakarparianIslamabadPakistan Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia T.I.Vyazemski Karadag Scientific Station-Nature Reserve—Branch of A.0.Kovalevsky Institute of Biology of the Southern Seas TheodosiaCrimea Zoological Institute of the RAS Saint PetersbourgRussia Institute of Zoology Academy of Sciences of the Republic of UzbekistanYunusabadTashkentUzbekistan museum Koenig Bonn LIBLeibniz Institute for the Analysis of Biodiversity ChangeBonnGermany UFZ-Helmholtz Centre for Environmental Research Department of Conservation BiologyPermoserstrasse 1504318 LeipzigGermany

Influenced by rapid changes in climate and landscape features since the miocene,widely distributed species provide suitable models to study the environmental impact on their evolution and current genetic *** dice snake Natrix tessellata,widely distributed in the Western Palearctic is one such *** aimed to resolve a detailed phylogeography of *** with a focus on the Central Asian clade with 4 and the Anatolia clade with 3 mitochondrial lineages,trace their origin,and correlate the environmental changes that affected their distribution through *** expected time of divergence of both clades began at 3.7 mya in the Pliocene,reaching lineage differentiation approximately 1 million years *** genetic diversity in both clades is rich,suggesting different ancestral areas,glacial refugia,demographic changes,and colonization *** Caspian lineage is the most widespread lineage in Central Asia,distributed around the Caspian Sea and reaching the foothills of the Hindu Kush mountains in Afghanistan,and Eastern European lowlands in the *** distribution is limited by deserts,moun-tains,and cold steppe ***,Kazakhstan and Uzbekistan lineages followed the Amu Darya and the Syr Darya water systems in Central Asia,with ranges delimited by the large Kyzylkum and Karakum *** the western side,there are several lineages within the Anatolia clade that converged in the central part of the peninsula with 2 being endemic to Western *** distribution of both main clades was affected by expansion from their Pleistocene glacial refugia around the Caspian Sea and in the valleys of Central Asia as well as by environmental changes,mostly through aridification.

关键词： biogeography colonization Eurasia genetic diversity mitochondrial DNA Paratethys refugia water snakes.

Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas konrad Shahab Alizadeh Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini Chris Edwards Carina Scharf David George Behm Institute of Human movement Science Sport and HealthGraz UniversityGraz A-8010Austria School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada Department of Sport Injuries and Corrective Exercises Faculty of Sport SciencesShahid Bahonar University of KermanKerman 76169-13439Iran

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROm).However,to date more information is needed regarding which training variables might have greater influence on improvements in ***,the purpose of this metaanalysis was to investigate the effects of stretch training on ROm in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch ***:We searched through Pubmed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect ***,by applying a mixed-effect model,we performed the respective subgroup *** find potential relationships between stretch duration or age and effect sizes,we performed a ***:We found a significant overall effect,indicating that stretch training can increase ROm with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;pmuscular facilitation and static stretching produced greater ROm than did ballistic/dynamic ***,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROm compared to ***,further moderating analysis showed no significant relation or ***:When the goal is to maximize ROm in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be *** to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were

关键词： Flexibility Long-term stretching Stretch training

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德国南部钻石城太空送来的七万吨礼物

环球人文地理 2024年第3期 96-103页

作者：袁莘捷 lebaer Wolfgang Ralf ArTo konrad filbert Andrey＿Lobachev Sina Ettmer flickr

钻石受到无数人追捧，其高昂的价格也让人望而却步。让人意外的是，在德国巴伐利亚州的西部山区，人们竟用七万吨钻石，建造了一座闪闪发光的钻石城。诺德林根是一座中世纪小镇，距今已有上千年历史。这里四面都有围墙，是德国目前仅有...

钻石受到无数人追捧，其高昂的价格也让人望而却步。让人意外的是，在德国巴伐利亚州的西部山区，人们竟用七万吨钻石，建造了一座闪闪发光的钻石城。诺德林根是一座中世纪小镇，距今已有上千年历史。这里四面都有围墙，是德国目前仅有的三座完全被城墙环绕的城市之一。小镇曾经安宁祥和，也曾经饱经硝烟，而许多建筑，甚至差点毁于一场大火。

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Natural variation in social conditions affects male mate choosiness in the amphipod Gammarus roeselii

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Current Zoology 2022年第4期68卷 459-467页

作者： konrad Lipkowski Sophie Steigerwald Lisa m Schulte Carolin Sommer-Trembo Jonas Jourdan Department of Wildlife/Zoo-Animal-Biology and Systematics Institute for EcologyEvolution and Diversity Goethe University FrankfurtMaxvon-Laue-Straße 13Frankfurt am MainD-60438Germany Department of Environmental Science Stockholm UniversitySvante Arrheniusväg 8StockholmSE-11418Sweden Zoological Institute University of BaselVesalgasse 1BaselCH-4051Switzerland Department of Aquatic Ecotoxicology Institute for EcologyEvolution and DiversityGoethe University Frankfurt am MainFrankfurt am MainGermany

The extent of male mate choosiness is driven by a trade-off between various environmental factors associated with the costs of mate acquisition,quality assessment and opportunity *** knowledge about natural variation in male mate choosiness across different populations of the same species,however,remains *** this study,we compared male mate choosiness across 10 natural populations of the freshwater amphipod Gammarus roeselii(Gervais 1835),a species with overall high male mating investments,and evaluated the relative influence of population density and sex ratio(both affecting mate availability)on male mate *** investigated amplexus establishment after separating mating pairs and presenting focal males with a novel,size-matched female from the same *** analysis revealed considerable effects of sex ratio and(to a lesser extent)population density on time until amplexus establishment(choosiness).male amphipods are able to perceive variable social conditions(e.g.,sex ratio)and modify their mating strategy accordingly:We found choosiness to be reduced in increasingly male-biased populations,whereas selectivity increases when sex ratio becomes female *** this,our study expands our limited knowledge on natural variations in male mate choosiness and illustrates the importance of sex ratio(i.e.,level of competition)for male mating decisions in natural *** for variation in sex ratios,therefore,allows envisioning a distinctive variation of choosiness in natural populations and highlights the importance of considering social background information in future behavioral studies.

关键词： amplexus Crustacea local adaptation mate choice population density sex ratio