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International Journal of Ophthalmology(English edition) 2017年第10期10卷 1620-1623页

作者： Joaquín Fernández Manuel Rodríguez-Vallejo Javier martínez Ana Tauste david P Pi?ero Department of Ophthalmology(Qvision) Vithas Virgen del Mar Hospital Department of Ophthalmology Torrecárdenas Hospital Complex Department of Optics Pharmacology and AnatomyUniversity of Alicante Department of Ophthalmology(Oftalmar) Vithas Medimar International Hospital

I am Dr. david P Pifiero from the Department of Optics, Pharmacology and Anatomy of the University of Alicante and from the Department of Ophthalmology of Vithas Medimar （Oftalmar） and Vithas Virgen del Carmen （Qv... 详细信息

关键词： Figure LASIK Above-average defocus curves in photopic and mesopic vision with multifocal intraocular lenses after laser assisted in situ keratomileusis IOL

Spatial Distribution of Nymphs Populations Bactericera cockerelli Sulc in Tomato Crops(Physalis ixocarpa Brot)

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 449-458页

作者： Roberto Rivera-martínez Agustín david Acosta-Guadarrama JoséFrancisco Ramírez-Dávila Fidel Lara Vazquez Dulce Karen Figueroa Figueroa Autonomous University of the State of Mexico Cerrillo Piedras Blancas n/n km 15Toluca50200Mexico Laboratory of Entomology Research and Technology in Precision Farming UAEMCerrillo Piedras Blancas n/n km 15Toluca50200México

Tomato crops(Physalis ixocarpa Brot.)are produced in almost all Mexico,part of the United States and Central *** the tomato production has suffered economic losses of 70%to 80%due the presence of yellowing and floral abortion,whose causal agent has been attributed to the presence of phytoplasma;an insect vector of these phytoplasma is Bactericera cockerrelli *** control of this psyllid has lacked effectiveness because their spatial distribution is unknown within tomato *** study aimed to determine the spatial distribution of populations of nymphs of *** in four tomato plots,the determination of the spatial distribution was performed by means of *** experimental semivariogram was determined to adjust to a theoretical model(spherical,exponential or Gaussian)through the program Variowin 2.2,the adjustment was validated with the method of cross-validation and aggregation maps of the pest were obtained through Kriging with Surfer 9.0 *** short-term time-space stability of the pest was determined through the tests Crámer-von *** results showed that populations of nymphs of *** have a distribution of aggregate type,which was corroborated by density *** are not present in 100%of the surface of the experimental plots,which helps to direct control measures on specific areas of infestation.

关键词： Geostatistics Bactericera cockerelli Sulc Kriging

Canola and Oat Forage Potential Evaluation in Four Early Planting Dates

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 435-448页

作者： Juan Isidro Sánchez-Duarte david Guadalupe Reta-Sánchez JoséAntonio Cueto-Wong Arturo Reyes-González Esmeralda Ochoa-martínez Campo Experimental La Laguna Instituto Nacional de Investigaciones ForestalesAgrícolas y Pecuarias(INIFAP).Blvd.JoséSantos Valdez 1200 Pte.Col.CentroMatamorosCoahuilaCP 27440México

Canola and oat forage potential may be affected by climatic conditions when sown *** objective of this study was to evaluate the forage canola and oat potential in four early sowing dates(September 11 and 25;October 9 and 23)during the 2012-2013 and 2013-2014 cycles in Matamoros,Coahuila,*** cycle duration,chemical composition,dry matter(DM),crude protein(CP),and net energy for lactation(NEL)yields were *** temperatures and long photoperiods affected crops seeded on September 11,accelerating growth and reducing canola(26.6%-31.7%)and oat(15.8%)DM *** of September 25,canola cv IMC 205 reached DM yields(7746 kg ha^(-1)-9276 kg ha^(-1))similar to those obtained by oat(8115 kg ha^(-1)-9507 kg ha^(-1)),while canola cv Hyola 401 obtained such yields only until October *** chemical composition was better than that found in oat,with higher CP,but lower acid detergent fiber(ADF)and neutral detergent fiber(NDF)*** equaled oat CP yields(972 kg ha^(-1)-1215 kg ha^(-1))in the first sowing date,while in the other three other canola sowings reached higher yields(1193 kg ha^(-1)-1889 kg ha^(-1)).As for NEL yields,no difference was observed between both *** best sowing date for canola is from September 25 on,with CP production advantages over oat.

关键词： Avena sativa L. Brassica napus L.var.oleifera chemical composition dry matter yield nutrients

Automatic Mexican Sign Language Recognition Using Normalized Moments and Artificial Neural Networks

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Engineering（科研） 2016年第10期8卷 733-740页

作者： Francisco Solís david martínez Oscar Espinoza Universitary Center UAEM of Teotihuacan Valley Autonomous University of Mexico’s State Axapusco México

This document presents a computer vision system for the automatic recognition of Mexican Sign Language (MSL), based on normalized moments as invariant (to translation and scale transforms) descriptors, using artificial neural networks as pattern recognition model. An experimental feature selection was performed to reduce computational costs due to this work focusing on automatic recognition. The computer vision system includes four LED-reflectors of 700 lumens each in order to improve image acquisition quality;this illumination system allows reducing shadows in each sign of the MSL. MSL contains 27 signs in total but 6 of them are expressed with movement;this paper presents a framework for the automatic recognition of 21 static signs of MSL. The proposed system achieved 93% of recognition rate.

关键词： Mexican Sign Language Automatic Sign Language Recognition Normalized Moments Computer Vision System

A review of the thermal stability of metastable austenite in steels:martensite formation

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Journal of Materials Science & Technology 2021年第32期91卷 200-214页

作者： Yong Li david San martín Jinliang Wang Chenchong Wang Wei Xu State key laboratory of rolling and automation Northeastern UniversityShenyang 110819China Materalia Research Group Centro Nacional de Investigaciones Metalúrgicas(CENIM-CSIC)Avda Gregorio del Amo 8Madrid E-28040Spain School of Mechanical and Power Engineering Guangdong Ocean UniversityZhanjiang 524088China

Metastable austenite plays a critical role in achieving improved combinations of high strength and high ductility/toughness in the design of advanced high-strength steels(AHSS). The thermal stability of metastable austenite determines the transformation characteristics of AHSS and thus primarily determines the microstructure evolution during complex processes, e.g., the quenching and partitioning process, to achieve the desirable microstructure. This study provides a review of the thermal stability of austenite and its influence on martensitic transformation from both experimental and theoretical modeling perspectives. From the experimental perspective, factors affecting the thermal stability are analyzed,the relative sensitivities are compared, and their corresponding mechanisms are discussed. From the theoretical modeling perspective, the most representative kinetic models that describe athermal and isothermal martensitic transformation are reviewed. The advantages, shortcomings, and applicability of each model are discussed. The systematic review of both experimental and theoretical aspects reveals critical factors in tailoring the stability of metastable austenite and, therefore, provides guidance for the design of advanced steels.

关键词： Austenite Thermal stability martensitic transformation Kinetic models

Effective use of FibroTest to generate decision trees in hepatitis C

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World Journal of Gastroenterology 2009年第21期15卷 2617-2622页

作者： Dana Lau-Corona Luís Alberto Pineda Héctor Hugo Avilés Gabriela Gutiérrez-Reyes Blanca Eugenia Farfan-Labonne Rafael Núez-Nateras Alan Bonder Rosalinda martínez-García Clara Corona-Lau Marco Antonio Olivera-martínez Maria Concepción Gutiérrez-Ruiz Guillermo Robles-Díaz david Kershenobich Department of Experimental Medicine School of MedicineUniversidad Nacional Autonoma de MexicoGeneral Hospital of Mexico Department of Computer Sciences Institute for Applied Mathematics and SystemsUniversidad Nacional Autonoma de Mexico Department of Gastroenterology Lomas Altas Clinic

AIM： To assess the usefulness of FibroTest to forecast scores by constructing decision trees in patients with chronic hepatitis C.METHODS： We used the C4.5 classification algorithm to construct decision trees with data from 261 patients with chronic hepatitis C without a liver biopsy. The FibroTest attributes of age, gender, bilirubin, apolipoprotein, haptoglobin, α2 macroglobulin, and γ-glutamyl transpeptidase were used as predictors, and the FibroTest score as the target. For testing, a 10-fold cross validation was used.RESULTS： The overall classification error was 14.9% （accuracy 85.1%）. FibroTest＇s cases with true scores of FO and F4 were classified with very high accuracy （18/20 for FO, 9/9 for FO-1 and 92/96 for F4） and the largest confusion centered on F3. The algorithm produced a set of compound rules out of the ten classification trees and was used to classify the 261 patients. The rules for the classification of patients in FO and F4 were effective in more than 75% of the cases in which they were tested.CONCLUSION： The recognition of clinical subgroups should help to enhance our ability to assess differences in fibrosis scores in clinical studies and improve our understanding of fibrosis progression,

关键词： Hepatitis C FibroTest Decision trees C4.5algorithm Non-invasive biomarkers

Evaluation of a new nomogram for Ferrara ring segment implantation in keratoconus

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1371-1383页

作者： Joaquín Fernández Cristina Peris-martínez Antonio Pérez-Rueda Sidi Mohamed Hamida Abdelkader María JoséRoig-Revert david P.Pinero Department of Ophthalmology(Qvision) Vithas Virgen del Mar HospitalAlmeria 04120Spain Department of Ophthalmology Torrecardenas Hospital ComplexAlmeria 04009Spain Comea and External Diseases Unit FISABIO-Oftalmologia Medica(FOM)Valencia 46015Spain Avino Peris Eye Clinic Valencia 46001Spain Department of Surgery OphthalmologyUniversity of ValenciaValencia 46010Spain Department of Optics Pharmacologyand AnatomyUniversity of AlicanteAlicante 03690Spain

AIM:To evaluate the short-term clinical outcomes of Ferrara rings in keratoconus using an optimized nomogram developed after several years of research and retrospective analysis of clinical ***:This prospective longitudinal non-comparative clinical trial evaluated 88 eyes of 88 patients(age 18-62 y)with keratoconus diagnosis from two Spanish *** ring segment(AJL Ophthalmic)implantation was performed in all cases,using the mechanical procedure in 25 eyes(28.4%)and a femtosecond laser-assisted procedure in 63 eyes(71.6%).The ring segments implanted in each case were selected using a new optimized nomogram that considered variables such as anterior corneal asphericity and astigmatism or the discrepancy among astigmatism and coma ***,refractive,corneal topographic,aberrometric,and pachymetric changes after surgery were evaluated during a 3-month ***:The implants induced a significant refractive change as well as an improvement in uncorrected(UDVA)and corrected distance visual acuity(CDVA;P<0.001).Postoperative CDVA of 0.10 log MAR or better was achieved in 28.4%and 46.5%of eyes,*** eyes(2.3%)lost two or more lines of CDVA whereas a total of 53.5%of eyes gained lines of CDVA.A significant central anterior and posterior corneal flattening was induced(P≤0.003),with a significant reduction of anterior(P<0.001)and posterior corneal astigmatisms(P=0.048),and a change in anterior asphericity(P<0.001).Total primary coma(6 mm pupil)change was also statistically significant(preoperative 3.66±3.04μm vs postoperative 2.33±2.26μm,P<0.001).No significant differences were found in the effect of ring segments between cases implanted using the mechanical and femtosecond techniques(P≥0.101).CONCLUSION:The implantation of Ferrara rings based on the nomogram evaluated is safe and effective for promoting a visual rehabilitation in keratoconus,with a relevant control of primary coma aberration.

关键词： intracorneal ring segment Ferrara ring segment femtosecond keratoconus coma aberration

Mexican Sign Language Recognition Using Jacobi-Fourier Moments

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Engineering（科研） 2015年第10期7卷 700-705页

作者： Francisco Solís Carina Toxqui david martínez University Center UAEM Teotihucan Valley Autonomous University of Mexico State M&eacute xico Polytechnic University of Tulancingo Tulancingo M&eacute xico

The present work introduces a system for recognizing static signs in Mexican Sign Language (MSL) using Jacobi-Fourier Moments (JFMs) and Artificial Neural Networks (ANN). The original color images of static signs are cropped, segmented and converted to grayscale. Then to reduce computational costs 64 JFMs were calculated to represent each image. The JFMs are sorted to select a subset that improves recognition according to a metric proposed by us based on a ratio between dispersion measures. Using WEKA software to test a Multilayer-Perceptron with this subset of JFMs reached 95% of recognition rate.

关键词： Mexican Sign Language Jacobi-Fourier Moments Digital Image Processing

Contributions to data transmission at critical moments on unmanned aerial vehicles

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Chinese Journal of Aeronautics 2023年第8期36卷 247-257页

作者： Jose Enrique RODRIGUEZ david SEGURADO Manuel SANCHEZ Jose Javier martInez Rafael GONZALEZ National Institute of Aerospace Technology Madrid 28850Spain Department of Computer Science University of AlcalaAlcala de HenaresMadrid 28054Spain

As for unmanned aircraft, the knowledge of the aircraft performance is directly related with the navigation, guidance, and control system programming. Therefore, the measured data in each phase of the flight must be sufficiently precise to obtain a good characterization of *** article proposes new methods of sending information to ground, which make it possible to know the aircraft behavior accurately, and for this purpose, four contributions have been made for ALO(Avión Ligero de Observación, Spanish acronym for Light Observation Aircraft). Currently, the characterization is based on data obtained at ten samples per second, insufficient to acquire detailed knowledge of what happened during the whole flight of an aircraft. As a result of these contributions, many more samples per second of accelerations and angular velocities are obtained at the most critical moments of the flight, such as takeoff or landing. Among the improvements included are data compression techniques, providing references to locate the measured data in time and identifying labels of each parameter.

关键词： Critical moments Data transmission Datacompression tech-niques Radio-modem Recommended Standard 232(RS-232) Unmannedaerial vehicle

Switchgrass Biochar Effects on Plant Biomass and Microbial Dynamics in Two Soils from Different Regions

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Pedosphere 2015年第3期25卷 329-342页

作者： Charlene N.KELLY Francisco C.CALDERóN Verónica ACOSTA-martínez Maysoon M.MIKHA Joseph BENJAMIN david W.RUTHERFORD Colleen E.ROSTAD Western Carolina University Department of Geosciences and Natural Resources331 Stillwell HallCullowheeNC 28723 (USA) U.S.Geological Survey Denver CO 80225 (USA) USDA-ARS Akron CO 80720 (USA) USDA-ARS Lubbock TX 79403 (USA)

Biochar amendments to soils may alter soil function and fertility in various ways, including through induced changes in the microbial community. We assessed microbial activity and community composition of two distinct clayey soil types, an Aridisol from Colorado （CO） in the U.S. Central Great Plains, and an Alfisol from Virginia （VA） in the southeastern USA following the application of switchgrass （Panicum virgatum） biochar. The switchgrass biochar was applied at four levels, 0%,0, 2.5%, 5%, and 10%, approximately equivalent to biochar additions of 0, 25, 50, and 100 t ha^-1, respectively, to the soils grown with wheat （Triticum aestivum） in an eight-week growth chamber experiment. We measured wheat shoot biomass and nitrogen （N） content and soil nutrient availability and N mineralization rates, and characterized the microbial fatty acid methyl ester （FAME） profiles of the soils. Net N mineralization rates decreased in both soils in proportion to an increase in biochar levels, but the effect was more marked in the VA soil, where net N mineralization decreased from -2.1 to -38.4 mg kg^-1. The 10% biochar addition increased soil pH, electrical conductivity, Mehlich- and bicarbonate-extractable phosphorus （P）, and extractable potassium （K） in both soil types. The wheat shoot biomass decreased from 17.7 to 9.1 g with incremental additions of biochar in the CO soil, but no difference was noted in plants grown in the VA soil. The FAME recovery assay indicated that the switchgrass biochar addition could introduce artifacts in analysis, so the results needed to be interpreted with caution. Non-corrected total FAME concentrations indicated a decline by 457o and 34% with 10% biochar addition in the CO and VA soils, respectively, though these differences became nonsignificant when the extraction efficiency correction factor was applied. A significant decline in the fungi：bacteria ratio was still evident upon correction in the CO soil with biochar. Switchgrass biochar had the p

关键词： correction factor extraction efficiency fatty acid methyl ester profile nitrogen mineralization soil microbial community soil nutrient availability wheat