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Segregated Distribution of Liriope tetraphylla, Aglaura hemistoma and Nausithoe punctata (Cnidaria) in the Southern Gulf of Mexico

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Open Journal of Ecology 2016年第9期6卷 568-578页

作者： César flores-Coto Alejandro Puente-Tapia Laura Sanvicente Añorve Mariana fernández-Alamo Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de México Ciudad Universitaria México D.F. Mexico facultad de Ciencias Universidad Nacional Autónoma de México Ciudad Universitaria México D.F. Mexico

In order to study the segregated distribution of the three most abundant jellyfish species in the southern Gulf of Mexico, a total of 85 stations were sampled during an oceanographic cruise from 19 May to 18 June 2006. Trawling took place from surface to a maximum depth of 200 m, using a Bongo net with a 61 cm mouth diameter and 333 and 500 μm mesh sizes. Temperature and salinity were recorded. Samples were preserved in 4% formalin, neutralized with sodium borate, and changed to 70% ethylic alcohol after 24 hours for conservation. The jellyfish data were standardized to 100 m3 of filtered water. A total of 10,610 jellyfish were collected from the 333 μm mesh size net, of which eight species represented 88.49% of the total density: Aglaura hemistoma, Liriope tetraphylla, Nausithoe punctata, Clytia hemisphaerica, Persa incolorata, Obelia spp., Clytia folleata and Eutima gracilis. The former three species are the subject of this study. The results obtained indicate that the high density areas of these three species have a segregated distribution. Segregation values (White’s index) recorded between pairs of specie were very high: L. tetraphylla - A. hemistoma, 0.88;L. tetraphylla - N. punctata, 0.86 and A. hemistoma - N. punctata, 0.84. The spatial distribution of the high density areas of these species fits well with the three hydrodynamically different areas: A. hemistoma in Campeche Bank, L. tetraphylla on the Campeche and Tabasco shelves and N. punctata in Campeche Bay. This spatial distribution pattern corresponds to their main habitat and reproductive habits of the species, as well as the influence of the hydrodynamics that dominate each area.

关键词： Cnidarians Segregated Distribution Southern Gulf Mexico

Strengthening Eating Habits through a Communication Program, Case Study： Colegio Inter Canadiense de Puebla

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通讯和计算机（中英文版） 2011年第11期8卷 988-996页

作者： Jesus Roberto Sanchez Reina Hilda Gabriela Hernandez flores Jose Manuel ramos Rodriguez Universidad lnteramericana para el desarrollo Campus Atlixco Puebla 72000 Mexico Communications Science faculty Benemdrita Universidad Aut6noma de Puebla Puebla 72000 Mexico faculty of Communication. Autonomous University of Puebla Mexico Puebla CP 72800 Mexico

Electrostatic and Magnetostatic forces That Arise from Electrostatic and Magnetostatic Pressures

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Journal of Electromagnetic Analysis and Applications 2019年第3期11卷 25-40页

作者： José-Luis Jiménez-Ramírez Ignacio Campos-flores José-Antonio-Eduardo Roa-Neri Departamento de física Facultad de Ciencias Universidad Nacional Autónoma de México CDMX México área de física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México

With the insight provided by a balance equation of electromagnetic momentum, we compare the force on a dielectric slab inside a capacitor with the force on a magnetizable rod inside a solenoid. We conclude that these forces are not exactly analogous, as usually thought. We present a device that is a proper analogy of the case of a dielectric slab inside a capacitor. Our analysis shows the significance of the electrostatic and magnetostatic pressures to the understanding of these effects and shows the conceptual differences between both cases.

关键词： Polarizable Electric and Magnetic Media Electric and Magnetic Pressures Electromagnetic force Densities Macroscopic Maxwell Equations Balance Equations of Electromagnetic Momentum

Cardiac Lesions in Naturally Infected Dogs with Trypanosoma cruzi

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Journal of Agricultural Science and Technology(A) 2011年第6期1卷 932-938页

作者： K. Y. Acosta-Viana E. Guzman-Marin M. Jimenez-Coello M. A. Torres-Leon R. f. Colin-flores A.Ortega-Pacheco Laboratory of Cell Biology C.A. Biomedicine of Infectious and Parasitic Diseases Regional Research Centre ＂Dr. Hideyo Noguchi＂ Autonomous University of Yucatan Av. Itzaes # 490 Merida Yucatan Mexico Laboratory of Animal Pathology Faculty of Veterinary Medicine Autonomous University of Yucatan Merida Yucatan AP 4-116 Mexico Department of Internal Medicine and Surgery Faculty of Veterinary Medicine Autonomous University of Yucatan Merida Yucatan AP 4-116 Mexico

With the purpose to determine the frequency and type of cardiac lesions in naturally exposed dogs to Trypanosoma cruzi, ninety one stray dogs, capture by the Canine and feline Control Center （dog pound） from the municipality of Merida, were studied. Before euthanasia, blood samples were taken to detect 72 cruzi antigens by indirect immunofluorescence antibody test and Western Blot and to detect the genome of parasite by Polymerase Chain Reaction. Immediately after euthanasia, hearts were macroscopically evaluated and a sample of the middle right atrial wall of each dog was taken for histopathological analyses. DNA was also obtained from paraffin blocks of seropositives animals with microscopic lesions to detect 72 cruzi genome. Of ninety one dogs, thirteen were seropositive. All seropositive dogs showed an association （P 〈 0.05） with lymphocytoplasmatic myocarditis. The presence of the 72 cruzi genome was also detected by PCR in cardiac septum tissue of seropositive dogs and in all the cases with microscopic lesions indicating the high pathogenicity of the local circulating strain. No association with macroscopic lesions was observed in seropositive dogs. Also, the presence of Dirofilaria immitis （D. immitis） was found in 6% of dogs evaluated. This study demonstrates a high tropism to cardiac tissue and virulence of the strains of 72 cruzi circulating in the studied dog population.

关键词： Dogs Trypanosoma cruzi IfAT PCR myocarditis.

A New Perspective of the force on a Magnetizable Rod inside a Solenoid

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Journal of Electromagnetic Analysis and Applications 2018年第10期10卷 171-183页

作者： José-Luis Jiménez-Ramírez Ignacio Campos-flores José-Antonio-Eduardo Roa-Neri Departamento de física Facultad de Ciencias Universidad Nacional Autónoma de México México D. F. México área de física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México

We analyze the familiar effect of the pulling of a magnetizable rod by a magnetic field inside a solenoid. We find that the analogy with the pulling of a dielectric slab by a charged capacitor is not as direct as usually thought. Indeed, there are two possibilities to pursue the analogy, according to the correspondence used,?either E → B and D → H, or E?→ H and D?→ B. One of these results in an incorrect sign in the force, while the other gives the correct result. We avoid this ambiguity in the usual energy method applying a momentum balance equation derived from Maxwell’s equations. This method permits the calculation of the force with a volume integration of a force density, or with a surface integration of a stress tensor. An interpretation of our results establishes that the force acts at the interface and has its origin in Maxwell′s magnetic stresses at the medium-vacuum interface. This approach provides new insights and a new perspective of the origin of this force.

关键词： force on a Rod in a Solenoid Magnetostatic force Maxwell Momentum Balance Equation

Study of the Reactivity of (100) felodipine Surface Model Based on DfT Concepts

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Open Journal of Physical Chemistry 2019年第1期9卷 1-12页

作者： Carlos Tepech-Carrillo Roxana Licona-Ibarra J. francisco Rivas-Silva Antonio flores-Riveros Instituto de física “Luis Rivera Terrazas” Benemérita Universidad Autónoma de Puebla Puebla México facultad de Ciencias Químicas Benemérita Universidad Autónoma de Puebla Puebla Mexico

In this study, Density functional Theory including a dispersion correction is employed to model and analyze the structural, electronic and local reactivity of the (100) surface of felodipine. The surface energy calculated at the Generalized Gradient Approximation (GGA) level, along with plane waves as basis set and ultrasoft pseudopotentials, shows that the (100) surface is the most stable as compared to the (010) and (110) ones. In particular, we have focused on performing a quantitative study of the reactivity of the surface by means of the fukui function and through the HOMO and LUMO populations. Our results can be related to some applications in the pharmaceutical chemistry of this compound.

关键词： 1 4-Dihydropyridine felodipine Density functional Theory fukui functions

How Does Arise the force on a Dielectric Slab in a Parallel Plate Capacitor?

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Journal of Electromagnetic Analysis and Applications 2018年第7期10卷 131-142页

作者： Ignacio Campos-flores José-Luis Jiménez-Ramírez José-Antonio-Eduardo Roa-Neri Departamento de física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City Mexico rea de física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City Mexico

We address the problem of the force exerted on a dielectric slab partially introduced into a charged parallel plate capacitor. This elementary problem is usually solved calculating this force as the gradient of an energy and attributing its origin to the action of the fringing field outside the capacitor on the dipoles of the dielectric slab. By applying Maxwell’s theory of electromagnetic stresses, we show that this force acts at the interface dielectric-vacuum and originates from the action of these stresses. This approach permits to obtain the force as a volume integration of a force density, or as a surface integral of a stress tensor. This force density and the stress tensor are part of a momentum balance equation derived from Maxwell’s equations.

关键词： Classical Electromagnetism Maxwell Equations Electrostatics Maxwell Balance Equation Maxwell Stress Tensor

基于多种深度学习算法的田间玉米籽粒检测与计数

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智慧农业（中英文） 2022年第4期4卷 49-60页

作者：刘晓航张昭刘嘉滢张漫李寒 Paulo flores 韩雄哲中国农业大学智慧农业系统集成研究教育部重点实验室北京100083 中国农业大学农业农村部农业信息获取技术重点实验室北京100083 北达科他州州立大学农业与生物工程系美国法戈58102 韩国江原大学生物系统工程系韩国春川24341 韩国江原大学韩国春川24341

为快速准确获取玉米收获过程中遗失籽粒数信息,进行收割损失调节等管理,对比评估了单阶段和两阶段主流目标检测网络对田间玉米籽粒计数的性能。首先,利用RGB相机获取包含不同背景和不同光照的图像数据,并进一步生成数据集;其次,构建籽... 详细信息

为快速准确获取玉米收获过程中遗失籽粒数信息,进行收割损失调节等管理,对比评估了单阶段和两阶段主流目标检测网络对田间玉米籽粒计数的性能。首先,利用RGB相机获取包含不同背景和不同光照的图像数据,并进一步生成数据集;其次,构建籽粒识别的不同目标检测网络,包括Mask RCNN、EfficientDet-D5、YOLOv5-L、YOLOX-L,并利用所采集的420幅有效图像对构建的四种网络进行训练、验证、测试,图像数分别为200、40和180幅;最后,依据测试集图像的识别结果进行籽粒计数性能评价。试验结果表明,YOLOv5-L网络对测试集图像检测的平均精度为78.3%,模型尺寸仅为89.3 MB;籽粒计数的检测正确率、漏检率和f1值分别为90.7%、9.3%和91.1%,处理速度为55.55 f/s,识别与计数性能均优于Mask R-CNN、EfficientDet-D5和YOLOX-L网络,并对具有不同地表遮挡程度和籽粒聚集状态的图像具有较强的鲁棒性。深度学习目标检测网络YOLOv5-L可实现实际作业中玉米收获损失籽粒的实时监测,精度高、适用性强。

关键词：收获损失田间玉米籽粒深度学习籽粒计数 YOLOv5-L YOLOX-L Mask R-CNN EfficientDet-D5

Balance Equations of Electromagnetic Angular Momentum

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Journal of Electromagnetic Analysis and Applications 2017年第12期9卷 203-217页

作者： Ignacio Campos-flores José Luis Jiménez-Ramírez José Antonio Eduardo Roa-Neri Departamento de física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City México área de física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City México

We give theoretical foundation to torque densities proposed in the past, like the one used by Beth to study experimentally the action of circularly polarized radiation on a birefringent material, or that proposed by Mansuripur to resolve a seeming paradox concerning the Lorentz force law and relativity. Our results provide new insights into electromagnetic theory, since they provide a unified and general treatment of the balance of lineal and angular momentum that permits a better assessment of some torques. Thus in this work we extend the derivations we have made of balance equations for electromagnetic linear momentum to balance equations for electromagnetic angular momentum. These balance equations are derived from the macroscopic Maxwell equations by means of vector and tensor identities and from the different ways in which these equations are written in terms of fields E, D, B, and H, as well as polarizations P, and M. Therefore these balance equations are as sound as the macroscopic Maxwell equations, with the limitations of the constitutive relations.

关键词： Balance Equations foundations of Electrodynamics Electromagnetic Angular Momentum Macroscopic Maxwell Equations Abraham-Minkowski Controversy