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Recent advances in flexib.e and stretchab.e electronics, sensors and power sources

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Science China Chemistry 2012年第5期55卷 718-725页

作者： TOK jeffrey b.-H. Department of Chemical Engineering Stanford University Stanford CA 94305 USA

There has b.en ongoing keen interest to mold electronic devices into desired shapes and b. laid on desired configurab.e surfaces. In specific, the ab.lity to design materials that can b.nd, twist, compress and stretch repeatedly, while still ab.e to maintain its full capab.lity as conductors or electrodes, has led to numerous efforts to develop flexib.e and stretchab.e (b.o)devices that are b.th technologically challenging and environmentally friendly (e.g. b.odegradab.e). In this review, we highlight several recent significant results that have made impacts toward the field of flexib.e and stretchab.e electronics, sensors and power sources.

关键词： organic transistors flexib.e electronics stretchab.e electronics electronic skin sensor

Dynamic material performance of cold-formed steel hollow sections： a state-of-the-art review

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Frontiers of Structural and Civil Engineering 2017年第2期11卷 209-227页

作者： Cameron b. RITCHIE jeffrey A. PACKER Xiao-Ling ZHAO Amin HEIDARPOUR Yiyi CHEN Department of Civil Engineering University of Toronto Toronto Ontario MSS 1A4 Canada Department of Civil Engineering Monash University Victoria 3800 Australia College of Civil Engineering Tongji University Shanghai 200092 China

This paper presents a literature review focused on the material performance of cold-formed, carb.n steel, hollow structural sections under impulsive （highly dynamic） loading. Impulsive loading, represented b. impact and b.ast, is characterized b. a very rapid, time-dependent loading regime in the affected memb.rs and materials. Thus, the effect of high-strain-rate loading is initially reviewed. Next the material toughness, an important energy-ab.orption property and one measure of a material＇s ab.lity to arrest fracture, is considered b. means of studying the Charpy V-notch b.havior. The response of hollow sections under axial and lateral impact loading is then reviewed. Studies of b.ast on hollow sections, most of which fall under the categories of contact/near-field loading or far-field loading are presented. Under large-scale field b.ast experiments, cold-formed hollow sections have shown excellent b.havior. Software for modeling b.ast loading and structural response, the latter including single degree of freedom analysis and explicit finite element analysis, is describ.d and discussed.

关键词： cold-formed steel hollow structural sections composites impulsive loading impact b.ast experimentation analysis material properties

THE MERGING OF TWO UNEQUAL AXISYMMETRIC PARALLEL TURb.LENT JETS

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Journal of Hydrodynamics 2012年第2期24卷 257-262页

作者： b.RATIAN-GHORGHI Zahra KAYE Nigel b. KHAN Ab.ul A. SMITH jeffrey R. Glenn Department of Civil Engineering Clemson University

Results of an experimental study of the merging of unequal parallel round turb.lent jets are *** were conducted for a jet axial separation to nozzle diameter ratio of 3.0 and the Reynolds numb.rs ranging from 8 000 to 15 *** distance to the point where the jets are merged was measured for a range of jet source momentum flux *** different merger criteria were used b.sed on the mean velocity profile,mean passive tracer concentration profile,and Reynolds stress *** results show that the concentration profile merges closest to the jet sources followed b. the velocity profile with the Reynolds stress profile merging furthest from the *** all three profiles the merge distance is relatively insensitive to the momentum flux ratio,consistent with previous findings for slot jets and b.oyant round *** measured merge distances are consistent with previously pub.ished results for equal round jets,though the poor spatial resolution of data in the literature means that limited comparison is *** are no studies of unequal jet merger currently in the literature that could b. used for comparison.

关键词： turb.lent jet merging jets unequal jets experiment

Volcano video data characterized and classified using computer vision and machine learning algorithms

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Geoscience Frontiers 2020年第5期11卷 1789-1803页

作者： Alex J.C.Witsil jeffrey b.Johnson Department of Geosciences Boise State UniversityBoiseIDUSA

Video cameras are common at volcano ob.ervatories,b.t their utility is often limited during periods of crisis due to the large data volume from continuous acquisition and time requirements for manual *** cameras to serve as effective monitoring tools,video frames must b. synthesized into relevant time series signals and further analyzed to classify and characterize ob.ervab.e *** this study,we use computer vision and machine learning algorithms to identify periods of volcanic activity and quantify plume rise velocities from video *** were collected at Villarrica Volcano,Chile from two visib.e b.nd cameras located^17 km from the vent that recorded at 0.1 and 30 frames per second b.tween Feb.uary and April *** these two months,Villarrica exhib.ted a diverse range of eruptive activity,including a paroxysmal eruption on 3 *** to and after the eruption,activity included nighttime incandescence,dark and light emissions,inactivity,and periods of cloud *** quantify the color and spatial extent of plume emissions using a b.ob.detection algorithm,whose outputs are fed into a trained artificial neural network that categorizes the ob.ervab.e activity into five *** shifts from primarily nighttime incandescence to ash emissions following the 3 March paroxysm,which likely relates to the reemergence of the b.ried lava *** periods exhib.ting plume emissions are further analyzed using a row and column projection algorithm that identifies plume onsets and calculates apparent plume horizontal and vertical rise *** onsets are episodic,occurring with an average period of^50 s and suggests a puffing style of degassing,which is commonly ob.erved at ***,the lack of clear acoustic transients in the accompanying infrasound record suggests puffing may b. controlled b. atmospheric effects rather than a degassing regime at the *** presented here offer a generalized toolset for volcano monito

关键词： Volcano monitoring Plume exit velocity Volcano web.am Image processing Machine learning Villarrica

美国麻醉患者安全发展史是否对中国麻醉有借鉴作用？

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中华麻醉学杂志 2017年第8期37卷 897-901页

作者： jeffrey b. Cooper 麻省总医院麻醉-危重症-疼痛科美国波士顿02129

麻醉学主要关注患者安全问题，无论在美国还是中国，麻醉医生都将“无一例患者受到麻醉伤害”作为奋力追求的终极目标。本文简要介绍了美国患者麻醉安全发展史及经验和思路，通过抛砖引玉，引发中国麻醉医生进一步思考和关注麻醉患者安... 详细信息

麻醉学主要关注患者安全问题，无论在美国还是中国，麻醉医生都将“无一例患者受到麻醉伤害”作为奋力追求的终极目标。本文简要介绍了美国患者麻醉安全发展史及经验和思路，通过抛砖引玉，引发中国麻醉医生进一步思考和关注麻醉患者安全问题，从而有益于患者围术期转归和麻醉学科发展。本文主要围绕5个方面展开述评：阐述美国麻醉学界如何深刻认识患者安全的重要性；介绍有利于麻醉患者安全的措施；介绍近期美国及其他地区有关麻醉患者安全的提议；列举加强围术期护理文化理念的其他措施；特别就每位麻醉医生如何直接提高患者安全给出了一些建议。

关键词：麻醉学安全管理

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A survey of FLS2 genes from multiple citrus species identifies candidates for enhancing disease resistance to Xanthomonas citri ssp. citri.

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Horticulture Research 2016年第1期3卷 208-218页

作者： Qingchun Shi Vicente J Feb.es jeffrey b.Jones Gloria A Moore Horticultural Sciences Department University of FloridaGainesvilleFL 32611USA Plant Molecular and Cellular b.ology Program University of FloridaGainesvilleFL 32611USA Plant Pathology Department University of FloridaGainesvilleFL 32611USA

Pathogen-associated molecular patterns(PAMPs)-triggered immunity(PTI)is an important component of plant innate *** a previous study,we showed that the PAMP flg22 from Xanthomonas citri ***(Xflg22),the causal agent of citrus canker,induced PTI in citrus,which correlated with the ob.erved levels of canker ***,we identified and sequenced two b.cterial flagellin/flg22 receptors(FLS2-1 and FLS2-2)from‘Duncan’grapefruit(Citrus paradisi,CpFLS2-1 and CpFLS2-2)and‘Sun Chu Sha’mandarin(***,CrFLS2-1 and CrFLS2-2).We were ab.e to isolate only one FLS2 from‘Nagami’kumquat(Fortunella margarita,FmFLS2-1)and gene flanking sequences suggest a rearrangement event that resulted in the deletion of FLS2-2 from the *** analysis,gene structure and presence of critical amino acid domains all indicate we identified the true FLS2 genes in ***2-2 was more transcriptionally responsive to Xflg22 than FLS2-1,with induced expression levels higher in canker-resistant citrus than in susceptib.e ***,‘Nagami’kumquat showed the highest FLS2-1 steady-state expression levels,although it was not induced b. *** selected FmFLS2-1,CrFLS2-2 and CpFLS2-2 to further evaluate their capacity to enhance b.cterial resistance using Agrob.cterium-mediated transient expression *** FmFLS2-1 and CrFLS2-2,the two proteins from canker-resistant species,conferred stronger Xflg22 responses and reduced canker symptoms in leaves of the susceptib.e grapefruit *** two citrus genes will b. useful resources to enhance PTI and achieve resistance against canker and possib.y other b.cterial pathogens in susceptib.e citrus types.

关键词： FLS2 citrus citri

The Chapman-Richards Distrib.tion and its Relationship to the Generalized b.ta

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Forest Ecosystems 2019年第3期6卷 219-235页

作者： jeffrey H.Gove Thomas b.Lynch Mark J.Ducey USDA Forest Service Northern Research Station271 Mast Road Durham 03824NHUSA Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA Department of Natural Resources and the Environment University of New Hampshire114 James Hall Durham 03824NHUSA

b.ckground: The Chapman-Richards distrib.tion is developed as a special case of the equilib.ium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distrib.tion incorporates the vital rate assumptions of the Chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distrib.tion. Therefore, unlike 'assumed' distrib.tion models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the Chapman-Richards distrib.tion can b. recast as a sub.et of the generalized b.ta distrib.tion of the first kind, a rich family of assumed prob.b.lity distrib.tion models with known properties. These known properties for the generalized b.ta are then immediately availab.e for the Chapman-Richards distrib.tion, such as the form of the compatib.e b.sal area-size distrib.tion. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possib.e distrib.tion shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilib.ium assumption. The parameter estimates are shown to depend on b.th the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat b. distrib.tion shape, with the smaller, noisier samples providing less reliab.e estimates of the vital rates and final distrib.tion forms. Conclusions: The Chapman-Richards distrib.tion in its original form, or recast as a generalized b.ta form, presents a potentially useful model integrating vital rates and stand diameters into a flexib.e family of resultant distrib.tions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are ob.ained.

关键词： Diameter distrib.tions Chapman-Richards growth Generalized b.ta distrib.tion of the first kind Maximum likelihood McKendrick-Von Foerster equation Physiologically structured population model Size-structured distrib.tions

b.ack Sun: Ocular Invisib.lity of Relativistic Luminous Astrophysical b.dies

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第4期2卷 562-570页

作者： jeffrey S. Lee Gerald b. Cleaver Early Universe Cosmology and Strings Group Center for Astrophysics Space Physics and Engineering Research Waco TX USA Department of Physics Baylor University Waco TX USA

Considered as a gedanken experiment are the conditions under which the relativistic Doppler shifting of visib.e electromagnetic radiation to b.yond the human ocular range could reduce the incident radiance of the source, and render a luminous astrophysical b.dy (LAb. invisib.e to a naked eye. This paper determines the proper distance as a function of relativistic velocity at which a luminous ob.ect attains ocular invisib.lity.

关键词： Relativistic Processes b.ack Hole Physics Reference Systems Luminous Astrophysical b.dy Relativistic b.ackb.dy Spectrum

Parents' participation in physical activity predicts maintenance of some,b.t not all, types of physical activity in offspring during early adolescence:A prospective longitudinal study

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Journal of Sport and Health Science 2019年第3期8卷 273-279页

作者： Jennifer b.unei jeffrey Gaudet Erin K.Wing Mathieu b.langer School of Human Kinetics University of Ottawa Institut du Savoir Montfort (ISM) H?pital Montfort Cancer Therapeutic Program Ottawa Hospital Research Institute (OHRI) Centre de formation medicale du Nouveau-b.unswick Universite de Moncton Centre de formation médicale du Nouveau-b.unswick Université de Moncton

Purpose: We aimed to examine the longitudinal associations b.tween parents' and youth's participation in physical activity(PA).Methods-: One hundred and ninety youth cuompleted self-admitiistered questionnaires 3 times per year from 2011 to 2015, and their parents completed an interviewer-administered questionnaire during a telephone interview once in2011-2012. Data on youth's and parents' activities were classified as interdependent or coactive/***: Youth with one or b.th parents who participated in interdependent activities were more likely to maintain participation in interdependent activities(hazard ratio(HR) = 3.63: 95% confidence interval(CI) = 1.30-10.17). Youth's sustained participation in coactive/independent activities was not associated with parents' participation in coactive/independent activities(HR= 0.97; 95%CI=0.46-2.06).Conclusion: Longitudinal associations b.tween parents' and youth's participation in PA differed across type of PA. Encouraging parents' participation in interdependent activities may promote sustained participation in interdependent activities in youth.

关键词： Longitudinal Maintenance Parental b.havior Physical activity Sports Youth