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Sex differences in the foraging behavior of a generalist hawkmoth

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Insect Science 2022年第1期29卷 304-314页

作者： Gordon P.Smith Goggy Davidowitz Ruben Alarcón Daniel R.Papaj Judith L.bronstein Department of Ecology and Evolutionary Biology University of ArizonaTucsonArizonaUSA Department of Entomology University of ArizonaTucsonArizonaUSA Department of Biology California State University Channel IslandsCamarilloCaliforniaUSA Current address:Department of Neurobiology and Behavior Cornell UniversityIthacaNew YorkUSA

Within-species variation in pollinator behavior is widely observed, but its causes have been minimally investigated. Pollinator sex is associated with large differences in behavior that may lead to predictable differences in flower foraging, but this expectation has not been explicitly tested. We investigate sex-associated differences in nectar-foraging behavior of the hawkmoth Hyles lineata, using pollen on the proboscis as a proxy for flower visitation. We tested two predictions emerging from the literature: (1) the sexes differ in the flower species they visit, (2) females are more specialized in flower choice. We also examined potential drivers underlying these predictions by performing field and laboratory experiments to test whether males (3) switch among flower species more frequently, or (4) fly farther and therefore encounter more species than females. Consistent with prediction (1), pollen load composition differed between the sexes, indicative of visitation differences. Contrary to prediction (2), females consistently carried more species-rich pollen loads than males. (3) Both sexes switched between flower species at similar rates, suggesting that differences in floral fidelity are unlikely to explain why females are less specialized than males. (4) Males flew longer distances than females;coupled with larger between-site differences in pollen composition for females, this result suggests that sex differences in mobility influence foraging, and that females may forage more frequently and in smaller areas than males. Together, our results demonstrate that sex-associated foraging differences can be large and consistent over time, and highlight the importance of sex as a driver of variation in pollinator behavior.

关键词： hawkmoths intraspecific variation pollination sex differences

Partial Shape Matching Without Point-Wise Correspondence

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Numerical Mathematics(Theory,Methods and Applications) 2013年第1期6卷 223-244页

作者： Jonathan Pokrass Alexander M.bronstein Michael M.bronstein School of Electrical Engineering Tel Aviv UniversityIsrael Institute of Computational Science Faculty of InformaticsUniversitàdella Svizzera Italiana(USI)LuganoSwitzerland

Partial similarity of shapes is a challenging problem arising in many important applications in computer vision,shape analysis,and graphics,*** one has to deal with partial information and acquisition *** problem is especially hard when the underlying shapes are non-rigid and are given up to a *** matching is usually approached by computing local descriptors on a pair of shapes and then establishing a point-wise non-bijective correspondence between the two,taking into account possibly different *** this paper,we introduce an alternative correspondence-less approach to matching fragments to an entire shape undergoing a non-rigid *** use region-wise local descriptors and optimize over the integration domains on which the integral descriptors of the two parts *** problem is regularized using the Mumford-Shah *** show an efficient discretization based on the Ambrosio-Tortorelli approximation generalized to triangular point clouds and meshes,and present experiments demonstrating the success of the proposed method.

关键词： Deformable shapes partial matching partial correspondence partial similarity diffusion geometry Laplace-Beltrami operator shape descriptors heat kernel signature Mumford-Shah regularization

Geometric and Photometric Data Fusion in Non-Rigid Shape Analysis

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Numerical Mathematics(Theory,Methods and Applications) 2013年第1期6卷 199-222页

作者： Artiom Kovnatsky Dan Raviv Michael M.bronstein Alexander M.bronstein Ron Kimmel Institute of Computational Science Faculty of InformaticsUniversitàdella Svizzera ItalianaLuganoSwitzerland School of Electrical Engineering Tel Aviv UniversityIsrael Technion–Israel Institute of Technology Computer Science DepartmentHaifaIsrael

In this paper,we explore the use of the diffusion geometry framework for the fusion of geometric and photometric information in local and global shape *** construction is based on the definition of a diffusion process on the shape manifold embedded into a high-dimensional space where the embedding coordinates represent the photometric *** results show that such data fusion is useful in coping with different challenges of shape analysis where pure geometric and pure photometric methods fail.

关键词： Laplace-Beltrami operator diffusion equation heat kernel descriptors 3D shape retrieval deformation invariance

绝对伏特加，“绝对”经典!——访美国纽约摄影师Steve bronstein

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影像视觉 2007年第3期8卷 7-11页

作者：赵英 Steve bronstein

Sleve bronstein,拍摄绝对伏特加而出名,两次被授予独创性摄影师称号。不论是为大众公司设计的雪天道路堵塞场面,还是为可口可乐公司设计的原始热带海滩,他都能在工作室通过传统的模型制作和强大的数码后期里完成,而不需要去昂贵又有风... 详细信息

Sleve bronstein,拍摄绝对伏特加而出名,两次被授予独创性摄影师称号。不论是为大众公司设计的雪天道路堵塞场面,还是为可口可乐公司设计的原始热带海滩,他都能在工作室通过传统的模型制作和强大的数码后期里完成,而不需要去昂贵又有风险的外景拍摄。

关键词：伏特加摄影师经典纽约数码设计后期独创性大众公司道路堵塞

Two-dimensional Covalent Organic Frameworks（2D-COFs） Via Schiff-base Condensation Reactions Between Porphyrins

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Two-dimensional Covalent Organic Frameworks（2D-COFs） Via S...

Equal Switching Distribution Method for Multi-Level Cascaded Inverters

中国化学会第十六届胶体与界面化学会议

作者：胡雅 Hugo bronstein Matthew Blunt Department of Chemistry University College London School of Materials Science and Engineering Sun Yat-Sen University

Since the successful isolation of individual graphene sheets in 2003 two-dimensional covalent materials have evolved in to one of the most widely studied areas of chemistry and physics.A particularly successful way of synthesizing new 2 D covalent materials has been via a bottom-up approach in which suitably functionalised molecules are covalently linked together to form 2 D covalent-organic frameworks（2 D-COFs）.This approach has been employed with a range of different reactions schemes and molecular building *** important step forward in this area was the use of reversible reactions that allowed the formation of the 2 D-COF to take place under thermodynamic control,leading to the formation of highly ordered *** this work we present recent scanning tunneling microscopy（STM） and atomic force microscopy（AFM） results on the growth of 2 D-COFs using free-base and metal-containing tetraphenyl amine porphyrin（TAPP） building *** TAPP molecules are linked together via a Schiff-base condensation reaction with benzene-1,4-dicarboxaldehyde（BDCA）.This reaction forms imine linkages between the porphyrin *** controlling the synthesis conditions highly ordered and large scale（100’s nm） 2 D-COFs can be *** addition,by controlling the symmetry and chemical functionality of both the porphyrin and the linking aldehyde molecule 2 D-COFs with more complex structures can be ***,investigations on the possibility of post synthesis functionalization of the resulting 2 D-COF structures will be discussed.

关键词： On-surface synthesis Monolayer covalent-organic frameworks Scanning probe microscopy Schiff-base condensation

来源： cnki会议评论

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Energy and Power Engineering 2013年第9期5卷 560-569页

作者： Saad Tapuchi Raul Rabinovici Dmitry Baimel Nina Baimel Svetlana bronstein Department of Computer Science Sapir College Sderot Israel Department of Electrical and Computer Engineering Ben Gurion University Beer Sheva Israel Department of Electrical and Electronics Engineering Shamoon College of Engineering Beer Sheva Israel

The paper proposes a new method of equal switching distribution that can be applied to cascaded multi-level inverters. This method is based on the fact that in the cascaded multilevel inverters, the output phase voltage is the sum of voltage waveforms produced by all cascaded cells. By periodically exchanging cells’ voltage waveforms, the proposed method ensures equal average switchings distribution between all cascaded cells. This method is applied to the 13-level inverter, which consists of three cascaded 5-level H-bridge cells per phase. However, the proposed method can be extended to any desired number of voltage levels and applied to any type of cascaded multi-level inverter. Extensive simulation results of the tested 13-level inverter with the equal switching distribution are presented. Moreover, the proposed method is compared to the standard control approaches and its advantages are shown.

关键词： Switchings Cascaded Inverter Multi-Level PWM

Acute liver failure is frequent during heat stroke

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World Journal of Gastroenterology 2008年第1期14卷 158-159页

作者： JM Garcin JA bronstein S Cremades P Courbin F Cointet Clinique médicale hpital d'instruction des armées Bégin F 94163 Saint Mandé France Service de pathologie digestive hpital d'instruction des armées Clermont Tonnerre F 29200 Brest France

Acute liver failure (ALF) is relatively frequent during heat stroke (HS). This risk must be emphasized, because its incidence is higher than is usually thought. In a recent study by Weigand et al , two cases were reported in which liver failure was the leading symptom. We have confirmed their conclusion in a study of 25 cases of HS with ALF, compared with 25 other cases without ALF. Moreover, we observed that hypophosphatemia on admission could predict occurrence of ALF during HS. As for clinical and other biological parameters, phosphatemia should be monitored for at least 3 d in all cases of HS, even when it is thought to be mild.

关键词：中暑血磷酸盐过少急性肝功能衰竭肝脏疾病

Dizziness : a practical approach to diagnosis and management

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2007年

作者： Adolfo M. bronstein Thomas Lempert.

来源：畅想之星图书光盘版（南... 评论

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曙光系列收藏品：天然彩色钻石中初升的太阳

中国宝石 2008年第4期17卷 144-145页

作者： Alan bronstein

中国人对自然总是有着天生的敬畏，这种敬畏已经深深的融入了他们的文化、艺术以及精神形态的方方面面。在过去的200年间．科学已经将人类带入生物及矿物质的微妙世界，让人们欣赏自然的美妙与神奇。而对于天然彩色钻石世界的探寻，仅... 详细信息

中国人对自然总是有着天生的敬畏，这种敬畏已经深深的融入了他们的文化、艺术以及精神形态的方方面面。在过去的200年间．科学已经将人类带入生物及矿物质的微妙世界，让人们欣赏自然的美妙与神奇。而对于天然彩色钻石世界的探寻，仅仅是近年来的事情。那么为什么天然彩色钻石让人如此神往？而这些神奇的钻石又从何而来呢？

关键词：彩色钻石天然收藏品太阳中国人矿物质自然世界