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Severe <i>Citrus tristeza virus</i>Isolates from Eastern Mexico Are Related to the T36 Genotype Group

American Journal of Plant Sciences 2020年第10期11卷 1521-1532页

作者： Patricia Rivas-Valencia Santiago Domínguez-Monge Ricardo Santillán-Mendoza emiliano loeza-kuk Oscar Pérez-Hernández Cynthia G. Rodríguez-Quibrera Claudia Lomas-Barrié Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias-Campo Experimental Valle de México Carretera Los Reyes-Texcoco km 13.5 Coatlinchán Texcoco México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias-Campo Experimental Ixtacuaco Carretera Martínez de la Tor-re-Tlapacoyan km 4.5 Tlapacoyan Veracruz México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias-Campo Experimental Ixtacuaco Carretera Martínez de la Torre-Tlapacoyan km 4.5 Tlapacoyan Veracruz México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias-Campo Experimental Mocochá Carretera Mérida-Motul km 25 Mocochá Yucatán México School of Agricultural Sciences Northwest Missouri State University Maryville USA

Citrus tristeza virus (CTV) outbreaks have been reported in the main citrus growing region of Mexico in the past four years. Recently, in eastern Mexico (the major citrus-growing region in the country), severe CTV isolates have been detected. However, the molecular identity of observed isolates remains unestablished. This research was undertaken to elucidate the molecular characterization of CTV populations spreading in this region and to compare it with phylogeny of existing isolates. Genotyping of 32 collected isolates was performed using reverse-transcription polymerase chain reaction (RT-PCR) with sequence analysis of the coat protein (CP) gene, putatively associated with pathogenicity. This protein is a 25 kDa major capsid protein, which forms a long virion body coating 95% of the particle length. A comparative sequence analysis was performed using CTV sequences from different geographical origins already published and deposited in the GenBank databases. Phylogenetic analysis showed that the degree of sequence divergence among isolates correlated with their pathogenicity. Based on the sequencing results, the collected isolates were cate

关键词： CTV Epidemiology Severe Isolates Stem Pitting Quick Decline Coat Protein Gene

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MULTIGRID METHOD FOR A MODIFIED CURVATURE DRIVEN DIFFUSION MODEL FOR IMAGE INPAINTING

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Journal of Computational Mathematics 2008年第6期26卷 856-875页

作者： Carlos Brito-loeza Department of Mathematical Sciences University of Liverpool

Digital inpainting is a fundamental problem in image processing and many variational models for this problem have appeared recently in the literature. Among them are the very successfully Total Variation （TV） model [11] designed for local inpainting and its improved version for large scale inpainting： the Curvature-Driven Diffusion （CDD） model [10]. For the above two models, their associated Euler Lagrange equations are highly nonlinear partial differential equations. For the TV model there exists a relatively fast and easy to implement fixed point method, so adapting the multigrid method of [24] to here is immediate. For the CDD model however, so far only the well known but usually very slow explicit time marching method has been reported and we explain why the implementation of a fixed point method for the CDD model is not straightforward. Consequently the multigrid method as in [Savage and Chen, Int. J. Comput. Math., 82 （2005）, pp. 1001-1015] will not work here. This fact represents a strong limitation to the range of applications of this model since usually fast solutions are expected. In this paper, we introduce a modification designed to enable a fixed point method to work and to preserve the features of the original CDD model. As a result, a fast and efficient multigrid method is developed for the modified model. Numerical experiments are presented to show the very good performance of the fast algorithm.

关键词： Image inpainting Variational models Regularization Multilevel methods.

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Recycling of reclaimed fibers from end-of-life tires in hot mix asphalt

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第5期7卷 678-687页

作者： Edoardo Bocci emiliano Prosperi Faculty of Engineering eCampus UniversityNovedrateCO 22060Italy Dipartimento di Ingegneria Civile Edile e Architettura UniversitàPolitecnica delle MarcheAncona 60131Italy

Nowadays, the disposal of end-of-life tires(ELT) is worldwide one of the major concerns for the environment as well as for public health. Crumb rubber and steel wires, the main byproducts(in terms of weight) deriving from the ELT processing, can be recycled in several ways. However, the textile fiber, representing about 10% of the waste by weight, is typically not reused and ends up in landfills or incinerators. The present paper deals with the use of reclaimed fibers from ELT in hot mix asphalt(HMA), with the aim to improve its performance. The study included the preliminary characterization of the fiber through microscope observation and Fourier trans form infrared(FTIR) spectroscopy and then the investigation of the mechanical properties of HMA containing ELT fibers, in comparison with an ordinary HMA with no fibers. In particular, indirect tensile strength(ITS), indirect tensile stiffness modulus(ITSM), semi-circular bending(SCB), three point bending(3PB)and indirect tensile fatigue(ITF) tests were carried out. The results showed that the use of ELT fibers does not reflect in a significant improvement in terms of strength and stiffness properties. However, the ELT fibers determine a noticeable increase of the HMA resistance to fatigue, probably related to the ability of the fibers in sewing the micro-crack edges and contrasting the macro-crack opening.

关键词： Road engineering Hot mix asphalt End-of-life tire Fiber Fatigue Recycling

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Secular dynamics of navigation satellites in the MEO and GSO regions

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Astrodynamics 2022年第4期6卷 357-374页

作者： Hanlun Lei emiliano Ortore Christian Circi School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education Nanjing UniversityNanjing 210023China Department of Astronautical Electrical and Energy EngineeringSapienza University of RomeVia Salaria 851Rome 00138Italy

In this study,a dynamical model is developed to describe the secular evolution of navigation satellites under the geocentric reference frame with the Laplace orbit as the fundamental *** disturbing function,involving the effects of Earth's oblateness and lunisolar gravitational attraction,is averaged over the orbital periods of both the satellite and the *** the regions of medium-Earth orbits and geosynchronous orbits,there are varieties of lunisolar resonances for governing the secular dynamics of navigation *** these resonances,we are interested in the ones occurring at the critical inclinations as well as the lunar node *** each resonance of interest,the resonant center and width are identified ***,dynamical maps are compared with the analytical results.

关键词： secular resonances Laplace plane navigation satellites dynamical maps

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A Mean Curvature Regularized Based Model for Demodulating Phase Maps from Fringe Patterns

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Communications in Computational Physics 2018年第6期24卷 27-43页

作者： Carlos Brito-loeza Ricardo Legarda-Saenz Arturo Espinosa-Romero Anabel Martin-Gonzalez CLIR at Facultad de Matematicas Universidad Autonoma de YucatanMexico

We introduce a variationalmethod for demodulating phasemaps fromfringe *** newmethod is based on themean curvature of the level sets of the phase surface that is used for *** performance of the method is illustrated w... 详细信息

关键词： Fringe analysis interferometry high-order regularization variational models

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Cross-Layer Framework for Fine-Grained Channel Access in Next Generation High-Density Wi Fi Networks

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China Communications 2016年第2期13卷 55-67页

作者： ZHAO Haitao ZHANG Shaojie emiliano Garcia-Palacios College of Electronic Science and Engineering National University of Defense Technology ECIT Institute Queen's University Belfast

Densely deployed Wi Fi networks will play a crucial role in providing the capacity for next generation mobile internet. However, due to increasing interference, overlapped channels in Wi Fi networks and throughput efficiency degradation, densely deployed Wi Fi networks is not a guarantee to obtain higher throughput. An emergent challenge is how to effi ciently utilize scarce spectrum resources, by matching physical layer resources to traffi c demand. In this aspect, access control allocation strategies play a pivotal role but remain too coarse-grained. As a solution, this research proposes a flexible framework for fine-grained channel width adaptation and multi-channel access in Wi Fi networks. This approach, named SFCA(Subcarrier Fine-grained Channel Access), adopts DOFDM(Discontinuous Orthogonal Frequency Division Multiplexing) at the PHY layer. It allocates the frequency resource with a subcarrier granularity, which facilitates the channel width adaptation for multi-channel access and thus brings more fl exibility and higher frequency efficiency. The MAC layer uses a frequencytime domain backoff scheme, which combines the popular time-domain BEB scheme with a frequency-domain backoff to decrease access collision, resulting in higher access probability for the contending nodes. SFCA is compared with FICA(an established access scheme)showing significant outperformance. Finally we present results for next generation 802.11 ac Wi Fi networks.

关键词： channel width adaptation channel access high-density WiFi

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Discussion on “Gaining Effciency via Weight Estimators for Multivariate Failure Time Data” by Fan, Zhou and Chen

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Science China Mathematics 2009年第6期52卷 1129-1130页

作者： kuk Anthony Department of Statistics and Applied Probability National University of Singapore Singapore

The survival analysis literature has always lagged behind the categorical data literature in developing methods to analyze clustered or multivariate data. While estimators based on

关键词： Discussion on Gaining Effciency via Weight Estimators for Multivariate Failure Time Data Zhou and Chen by Fan

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Towards very high RAP content asphalt mixes:A comprehensive performance-based study of rejuvenated binders

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第6期8卷 1022-1035页

作者： Marco Pasetto Andrea Baliello Giovanni Giacomello emiliano Pasquini Department of Civil Environmental and Architectural Engineering(ICEA)University of PaduaPaduaItaly

Hot recycling of reclaimed asphalt pavement(RAP)from replacement of deteriorated asphalt pavements is a widespread technique,and able to ensure clear economic and environmental *** this reason,paving industries,agencies and researchers are spending significant efforts in order to maximize such advantages by increasing the amount of RAP within new asphalt ***,adequate performance of recycled mixtures must be guaranteed despite the re-use of high amounts of RAP which involves the presence of aged,oxidized and stiffened *** this perspective,the present study aimed at evaluating the rheological properties at mid-service and high-service temperatures of bituminous blends composed by 40%of virgin binder and 60%of aged rejuvenated bitumen(simulating the aged hard bitumen coming from the RAP).Such proportion was selected to represent a high recycling rate of RAP(about 60%of the total weight of aggregates,RAP included).A chemical commercial additive at the liquid state was selected as rejuvenator;it was dosed at the optimum content based on empirical and rheological preliminary *** performance of the recycled blend was then compared to that of a virgin reference *** shear rheometer tests were carried out to determine the master curves and the failure characteristics(at mid and high service temperatures)of the selected *** effect of aging(related to the durability over the material lifetime)was also studied analyzing binders’responses in unaged,shortterm and long-term aged ***,experimental findings demonstrated the efficacy of the rejuvenation of recycled binders containing very high amount of aged bitumen.

关键词： Pavement engineering Hot recycling Reclaimed asphalt Rejuvenation DSR Rheology

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Reconfigurable elastomeric graded-index optical elements controlled by light

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Light(Science & Applications) 2018年第1期7卷 964-972页

作者： Angelo Angelini Federica Pirani Francesca Frascella emiliano Descrovi Department of Applied Science and Technology(DISAT) Politecnico di TorinoC.so Duca degli Abruzzi 24Torino IT-10129Italy Center for Sustainable Future Technologies@PoliTo Istituto Italiano di TecnologiaC.so Trento 21Torino IT-10129Italy

In many optical applications,there is an increasing need for dynamically tunable optical elements that are able to shape the wavefront of light‘on demand’.In this work,an elastomeric easy-to-fabricate optical element whose transmission functions can be reversibly phase configured by visible light is *** light responsivity of proper azopolymers incorporated within an elastomeric matrix is exploited to induce a light-controlled graded refractive index(GRIN)distribution within the bulk *** induced refractive index distribution is continuous and conformal to the intensity profile of the illumination at moderate power.A 100mW doubled-frequency Nd:YAG Gaussian beam focused to a 650μm waist is shown to induce a maximum relative refractive index change of~0.4%in the elastomeric matrix,with an approximately parabolic *** restoring characteristics of the elastomeric matrix enable full recovery of the initial homogeneous refractive index distribution within a few seconds when the incident laser is switched *** an exemplary application,the configurable GRIN element is used in a microscope-based imaging system for light control of the effective focal length.

关键词： optical switched index

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Effect of friction on the contact stress of a coated polymer gear

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Friction 2020年第6期8卷 1169-1177页

作者： Su-Min BAE kuk-Jin SEO Dae-Eun KIM Department of Mechanical Engineering Yonsei UniversitySeoul 03722Republic of Korea

Polymer gears are used extensively in various ***,durability issues have been emerging because of friction at gear tooth contact *** extend the lifetime of polymer gears,a low-frictional coating has been considered as a possible *** this study,a finite element simulation method was performed to investigate the contact stress between a pair of coated polymer *** simulation included various friction coefficients(COFs)for studying the effects of friction during the *** results revealed that the friction causes the contact stress to shift over the roll angle,which is attributed to the direction of the sliding friction based on a free-body *** also investigated the effects of coating and found that a thin coating has little effect on the bulk deformation behavior of the ***,the stress distribution in the coating at the pitch point was investigated as the COF *** zero friction,three notable stress regions were observed:1)the center of the surface,2)the end of the contact,and 3)the overall contact *** COF was increased in the micro-slip region of the contact interface,both tensile and compressive stresses in the coating *** study provides significant aid to engineers for understanding the stress response of the coating applied to polymer gears to achieve an optimal design.

关键词： coating contact stress finite element method(FEM) friction polymer gear

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