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Revealing the underlying mechanisms behind TE extraordinary THz transmission

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Photonics Research 2020年第4期8卷 430-439页

作者： SUZANNA FREER miguel camacho SERGEI A.KUZNETSOV RAFAEL R.BOIX miguel BERUETE miguel NAVARRO-CíA School of Physics and Astronomy University of BirminghamBirmingham B152TTUK Department of Physics and Astronomy University of ExeterExeter EX44QDUK Rzhanov Institute of Semiconductor Physics SB RAS Novosibirsk Branch TDIAM Novosibirsk 630090Russia Physics Department Novosibirsk State UniversityNovosibirsk 630090Russia Department of Electronics and Electromagnetism Faculty of PhysicsUniversity of Seville41012 SevilleSpain Antennas Group-TERALAB Universidad Pública de Navarra31006 PamplonaSpain Institute of Smart Cities Universidad Pública de Navarra31006 PamplonaSpain

Transmission through seemingly opaque surfaces,so-called extraordinary transmission,provides an exciting platform for strong light–matter interaction,spectroscopy,optical trapping,and color *** of the effort has been devoted to understanding and exploiting TM extraordinary transmission,while TE anomalous extraordinary transmission has been largely omitted in the *** is regrettable from a practical point of view since the stronger dependence of the TE anomalous extraordinary transmission on the array’s substrate provides additional design parameters for *** provide high-performance and cost-effective applications based on TE anomalous extraordinary transmission,a complete physical insight about the underlying mechanisms of the phenomenon must be first laid *** this end,resorting to a combined methodology including quasi-optical terahertz(THz)time-domain measurements,full-wave simulations,and method of moments analysis,subwavelength slit arrays under s-polarized illumination are studied here,filling the void in the current *** believe this work unequivocally reveals the leaky-wave role of the grounded-dielectric slab mode mediating in TE anomalous extraordinary transmission and provides the necessary framework to design practical high-performance THz components and systems.

关键词： Revealing the underlying mechanisms TE extraordinary transmission THz

Geophysical Modeling with Satellite Gravity Data: Eigen-6C4 vs. GGM Plus

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Engineering（科研） 2021年第12期13卷 690-706页

作者： miguel camacho Román Alvarez Posgrado en Ciencias de la Tierra Universidad Nacional Autónoma de México Mexico City Mexico Román Alvarez Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas (IIMAS) Universidad Nacional Autónoma de México CDMX Mexico City Mexico

Satellite data sets are an asset in global gravity collections;their characteristics vary in coverage and resolution. New collections appear often, and the user must adapt fast to their characteristics. Their use in geophysical modeling is rapidly increasing;with this in mind we compare two of the most densely populated sets: EIGEN-6C4 and GGMplus. We characterize them in terms of their frequency histograms, Free Air anomalies, power spectrum, and simple Bouguer anomalies. The nature of the digital elevation models used for data reduction is discussed. We conclude that the GGMplus data set offers a better spatial resolution. To evaluate their effect in geophysical modelling, we chose an inland region with a prominent volcanic structure in which we perform 3D inversions of the respective Bouguer anomalies, obtaining density variations that in principle can be associated with the geologic materials and the structure of the volcanic edifice. Model results are analyzed along sections of the inverted data;we conclude that the GGMplus data set offers higher resolution in the cases analyzed.

关键词： EIGEN-6C4 GGMplus Satellite Gravity Data 3D inversions Nevado de Toluca

Structural Analysis of TiC and TiC-C Core-Shell Nanostructures Produced by Pulsed-Laser Ablation

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Journal of Materials Science and Chemical Engineering 2023年第7期11卷 1-13页

作者： Luis Enrique Iniesta Piña miguel Ángel camacho López Rafael Vilchis Néstor Víctor Hugo Castrejón Sánchez Delfino Reyes Contreras Mestría en Ciencia de Materiales Facultad de Química Campus Rosedal Universidad Autónoma del Estado de México Toluca México Laboratorio de Fotomedicina Biofotónica y Espectroscopía Láser de Pulsos Ultracortos Facultad de Medicina Universidad Autónoma del Estado de México Toluca México Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM Toluca México TecNM/Tecnológico de Estudios Superiores de Jocotitlán Jocotitlán México Laboratorio de Acústica y Nanomateriales Facultad de Ciencias Campus el Cerrillo Universidad Autónoma del Estado de México Toluca México

This paper reports on the ablation process of a pure Ti solid target immersed in a C-enriched acetone solution, leading to the production of titanium carbide (TiC) and Ti-C core-shell nanostructures. The used route of synthesis is generally called pulsed laser ablation in liquid (PLAL). The presence of carbon structures in the solution contributed to the carbon content in the produced Ti-based nanomaterials. The atomic composition of the produced nanostructures was analyzed using SEM-EDS, while TEM micrographs revealed the formation of spherical TiC and core-shell nanostructures ranging from 40 to 100 nm. The identification of atomic planes by HRTEM confirmed a 10 nm diameter C-shell with a graphite structure surrounding the Ti-core. Raman spectroscopy allowed for the identification of D and G peaks for graphite and a Raman signal at 380 and 600 cm−1, assigned to TiC. The results contribute to the state-of-the-art production of TiC and Ti-C core-shell nanostructures using the PLAL route.

关键词： Laser Ablation TiC Nanoparticles Core-Shell Nanoparticles Pulsed Laser

Effect of split applications of urea on protein size distribution, physical dough properties, and baking performance of five experimental bread wheat lines

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Agricultural Sciences 2011年第3期2卷 181-190页

作者： Alma Rosa Islas-Rubio Karla Chávez-Quiroz Francisco Vásquez-Lara Brenda Silva-Espinoza María del Carmen Granados-Nevárez Humberto Gonzalez-Ríos miguel camacho-Casas Departamento de Tecnología de Alimentos de Origen Vegetal Centro de Investigación en Alimentación y Desarrollo A.C. Carretera a la Victoria Km 0.6 Hermosillo Sonora México Departamento de Tecnología de Alimentos de Origen Vegetal Centro de Investigación en Alimentación y Desarrollo A.C. Carretera a la Victoria Km 0.6 Hermosillo Sonora México. 83000

Five experimental bread wheat lines (BWL) were grown at the Yaqui Valley Experimental Station in Sonora, México during two consecutive growing cycles. The effect of five nitrogen fertilization (NF) treatments on protein size distribution (PSD), physical dough properties (PDP), and baking performance of the BWL was evaluated. Polymeric and monomeric proteins were evalu-ated by SE-HPLC. PDP were carried out by the National Mixograph and the TA-XT2 Texture Analyzer. Baking performance was evaluated using the straight dough method. Protein content (PC), main protein fractions (glutenins, gliadins, albumins-globulins), and mixograph development time (MDT) were significantly influenced by NF treatment and BWL but not by their interaction. On the other hand, PDP measured by the Kieffer rig, and baking performance were significantly influenced by the main factors (NF and BWL) and their interaction. The amount and timing of fertilizer applied to the BWL modified the PC, PSD, PDP, and bread loaf volume. PDP exhibited a larger variation in comparison to the PSD of glutenins. The split application of 150 kg of urea/ha (50-50-50) to all BWL showed a better loaf volume response than the same amount of urea applied at sowing (150-0-0). The application of 300 kg of urea/ha to all BWL, either at sowing or at three split applications of 100 kg of urea/ha each, resulted in higher flour unextractable polymeric protein (FUPP). On the other hand, the split application of 100-100-100 kg of urea/ha to three of the BWL represented the higher total unextractable polymeric protein (TUPP). Differences on PC and PSD were reflected on differences on PDP and bread loaf volume observed among the BWL.

关键词： Wheat Nitrogen Fertilization Protein Composition Dough Properties

Approximate Metric for a Rotating Deformed Mass

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International Journal of Astronomy and Astrophysics 2015年第1期5卷 1-10页

作者： Francisco Frutos-Alfaro Paulo Montero-camacho miguel Araya Javier Bonatti-González Space Research Center and School of Physics University of Costa Rica San José Costa Rica Nuclear Research Center and School of Physics University of Costa Rica San José Costa Rica

A new Kerr-like metric with quadrupole moment is obtained by means of perturbing the Kerr spacetime. The form of this new metric is simple as the Kerr metric. By comparison with the exterior Hartle-Thorne metric, it is shown that it could be matched to an interior solution. This approximate metric may represent the spacetime of a real astrophysical object with any Kerr rotation parameter a and slightly deformed.

关键词： Approximate Solutions of Einstein Equations Kerr Metric Erez-Rosen Metric Quadrupole

Mutational landscape of gastric adenocarcinoma in Latin America: A genetic approach for precision medicine

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Genes & Diseases 2022年第4期9卷 928-940页

作者： Dennis Cerrato-Izaguirre Yolanda I.Chirino Claudia M.García-Cuellar miguel Santibáñez-Andrade Diddier Prada Angélica Hernández-Guerrero Octavio Alonso Larraga Javier camacho Yesennia Sánchez-Pérez Subdirección de Investigación Básica Instituto Nacional de Cancerología(INCan)TlalpanCiudad de MéxicoCP 14080Mexico Departamento de Farmacología Centro de Investigación y de Estudios Avanzados del I.P.N.(CINVESTAV)Ciudad de MéxicoCP 07360Mexico Unidad de Biomedicina Facultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoLos Reyes IztacalaTlalnepantla de BazEstado de MéxicoCP 54090Mexico Departamento de Informática Biomédica Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoCoyoacánCiudad de MéxicoCP 04510Mexico Department of Environmental Health Science Mailman School of Public HealthColumbia UniversityNew YorkNY 10027USA Servicio de Endoscopía Instituto Nacional de Cancerología(INCan)TlalpanCiudad de MéxicoCP 14080Mexico

Latin-America (LATAM) is the second region in gastric cancer incidence;gastric adenocarcinoma (GA) represents 95% of all cases. We provide a mutational landscape of GA highlighting a) germline pathogenic variants associated with hereditary GA, b) germline risk variants associated with sporadic GA, and c) somatic variants present in sporadic GA in LATAM, and analyze how this landscape can be applied for precision medicine. We found that Brazil, Chile, Colombia, Mexico, Peru, and Venezuela are the countries with more published studies from LATAM explicitly related to GA. Our analysis displayed that different germline pathogenic variants for the CDH1 gene have been identified for hereditary GA in Brazilian, Chilean, Colombian, and Mexican populations. An increased risk of developing somatic GA is associated with the following germline risk variants: IL-4, IL-8, TNF-α, PTGS2, NFKB1, RAF1, KRAS and MAPK1 in Brazilian;IL-10 in Chilean;IL-10 in Colombian;EGFR and ERRB2 in Mexican, TCF7L2 and Chr8q24 in Venezuelan population. The path from mutational landscape to precision medicine requires four development levels: 1) Data compilation, 2) Data analysis and integration, 3) Development and approval of clinical approaches, and 4) Population benefits. Generating local genomic information is the initial padlock to overcome to generate and apply precision medicine.

关键词： Ethnicities Genome Latin America Mutati on Precisi on medicine Stomach neoplasms

Potassium Concentration by Natural ^40K-^40Ar Y Rays Detection in Four Basic Diet Products （Milk, Eggs, Wheat and Corn）

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Journal of Life Sciences 2011年第8期5卷 614-617页

作者： Juan Manuel Navarrete Trinidad Martinez Luis Cabrera Pilar Lizarraga miguel Angel Zuniga Michelle camacho Faculty of Chemistry Building D National University of Mexico CU Mexico City ZC 04510 Mexico

The purpose of this paper is double： first to measure the natural radioactivity in any food by detecting the omnipresent radiation of ^40K, and then to use this date to obtain the concentration of the important mineral nutrient K, by dividing the specific activity of the sample （Bq/g） by the specific activity of elementary K （31.19 Bq/g）. The method implies the γ rays detection emitted by natural ^40K-^40Ar present in foodstuff, by using a 3 × 3＂ low background NaI （TI） scintillation detector coupled to a PC charged with the Maestro Program. When this detection system is calibrated in order to determine its efficiency for 1461 KeV γrays emitted during ^40K-^40Ar decaying, it is possible to measure easily and with enough precision the specific activity due to natural ^40K present in any foodstuff. Once this figure is divided by the constant value of ^40K specific activity of elementary K, the concentration of this element in the foodstuff sample is established. This paper describes the procedure and shows the results obtained with four basic diet products： milk （powdered, light and cream）, eggs （yellow and white）, wheat （whole and refined flour） and corn （whole and cornstarch flour）. The possible application of this study seems to be to establish the necessary threshold to evaluate the importance of any possible radioactive contamination, as well as to measure the concentration of the mineral nutrient K in foodstuff, by means of an easy, practicable method. Also, it might be useful as an experiment for teaching purposes.

关键词： Radioactivity nourishment potassium concentration ^40K-^40Ar Y rays.

Radioisotopes and Analytical Chemistry

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World Journal of Nuclear Science and Technology 2013年第1期3卷 6-13页

作者： Manuel Navarrete Trinidad Martínez Alberto Fernández miguelángel Zúniga Michelle camacho Mónica Flores Department of Inorganic and Nuclear Chemistry Faculty of ChemistryNational University of MexicoMexico CityMexico

When Periodic Chart of elements is consulted to find natural radioisotopes, one firstly finds tritium, followed by 10Be, 14C, 50V and many others. Before Bi, 12 cosmogenic radioisotopes are listed. They are those continuously produced by nuclear reactions among light elements present in earthly atmosphere and radiations coming from the outside space. Eighteen additional primordial radioisotopes are listed. They were created at the same time that the non-radioactive isotopes composing the 92 natural elements in the periodic table. From Bi on, every isotope is radioactive, up to U. Then follow the artificial elements produced by laboratory nuclear reactions from Np to element with atomic number 118. In this way, from 118 known elements, 64 are radioactive, which amount 55% of all those units forming the chemical compounds. Therefore, the complete understanding of radioactivity should be a suitable tool to advance our knowledge of Universe, and consequent applications to get better living conditions. So, this paper deals with radioisotopes as suitable instruments for chemical analysis.

关键词： Radioisotopes Radiations Chemical Quantitative Analysis

Effect of the sintering technique on the ferroelectric and d33 piezoelectric coefficients of Bi0.5(Na0.84K0.16)0.5TiO3 ceramic

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Journal of Advanced Ceramics 2019年第2期8卷 278-288页

作者： G.HERNANDEZ-CUEVAS J.R.LEYVA MENDOZA P.E.GARCíA-CASILLAS C.A.RODRíGUEZ GONZáLEZ J.F.HERNANDEZ-PAZ G.HERRERA-PéREZ L.FUENTES-COBAS S.DíAZ DE LA TORRE O.RAYMOND-HERRERA H.camacho-MONTES Instituto de Ingeniería y Tecnología Universidad Autónoma de Ciudad JuárezAv.Del Charro 450 Norte Cd.JuárezChihuahua32310México Centro de Investigación en Materiales Avanzados Miguel de Cervantes 120Chihuahua 31109ChihuahuaMéxico Centro de Investigación e Innovación Tecnológica Instituto Politécnico NacionalCerrada de Cecati s/nAzcapotzalcoSanta Catarina02250Ciudad de MéxicoMéxico Centro de Nanociencias y Nanotecnología Universidad Nacional Autónoma de MéxicoKm.107 Carretera Tijuana-EnsenadaAP.14Ensenada 22860Baja CaliforniaMéxico

In the search of lead-free piezoelectric materials,ceramic processing techniques offer potential tools to increase the piezoelectric and ferroelectric properties in addition to new chemical *** of pure BNKT16(Bi0.5(Na0.84K0.16)0.5TiO3)phase were synthesized by sol–gel method with a low crystallization temperature(750℃).Ceramic samples were sintered by pressureless sintering(PLS),sinter-forging(SF),and spark plasma sintering(SPS)***,morphological,and chemical characterizations were performed by XRD,Raman,EDS,and *** samples by PLS and SF exhibit rod-like grains associated to bismuth *** highest remanent polarization(11.05μC/cm2),coercive field(26.2 kV/mm),and piezoelectric coefficient(165 pC/N)were obtained for SF *** piezoresponse force microscopy(PFM)analysis shows that the crystallites at the nanoscale exhibit piezoelectric phenomenon and the highest piezoelectric response is reported for PLS *** presence of the rhombohedral phase,the increase in grain and crystallite size,and the oriented rod-like inclusions favoring the crystallographic texture are facts that enhance the piezoelectric coefficient for BNKT16 piezoceramics.

关键词： lead-free piezoelectrics sol–gel pressureless sintering (PLS) sinter-forging (SF) spark plasma sintering(SPS) piezoresponse