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Open Journal of Ecology 2015年第12期5卷 574-581页

作者： Daniel Sierra-Franco martin Emilio Pereda-Solís josé Hugo martínez-Guerrero Irene Ruvalcaba Ortega Universidad Juárez del Estado de Durango Cuerpo Académico de Fauna Silvestre Durango México Facultad de medicina Veterinaria y Zootecnia Universidad Juárez del Estado de Durango Cuerpo Académico de Fauna Silvestre Durango México Facultad de Ciencias Biológicas Universidad Autónoma de Nuevo León Cuerpo Académico de Ecología y Biodiversidad San Nicolás de los Garza México

Grassland bird populations have declined more than any other group of bird species in North America. Some species such as the grasshopper (Ammodramus savannarum) and Baird’s sparrows (Ammodramus bairdii) are of particular conservation concern, since they have shown negative trends in their population over the last 50 years. Their winter ecology has only begun to be studied recently and information is limited. The purpose of this study is to achieve the morphometric characterization of these two grassland species during the wintering season. The study is conducted in the Rancho Santa Teresa located in Villa Hidalgo, Durango, mexico and the Ecological reserve “El Uno”, located in Janos, Chihuahua, mexico. During winter 2013-2014, 135 birds were captured;banded and zoometric measurements were taken such as total body weight, wing chord, tail length, culmen, and beak depth and width. Two indices of body condition (BCI) are also calculated. All measurements and indices are compared per species and per sex. Both species are sexed with molecular techniques, determining 20 females and 18 males for A. bairdii and 41 females and 56 males for A. savannarum. All variables are significant different between species (p measurements are not significantly different when comparing birds of different sexes (same species), with the exception of beak width of A. bairdii (p male’s weight, wing chord, tail length, as well as one of the body condition indices (BCI2) are significantly higher (p males’ for both species. BCI1 shows significant differences (p metric data obtained in this study can be used as reference values wintering populations of both species.

关键词： Grasshopper Sparrow Baird’s Sparrow Wintering morphometric Body Condition Index

Cost Optimisation for minimizing the Visual Impact of Ornamental Stone Quarrying. A Case Study in murcia Region

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Journal of Geoscience and Environment Protection 2018年第2期6卷 74-88页

作者： josé molina-Ruiz maría josé martínez-Sánchez Carmen Pérez-Sirvent mari Luz García-Lorenzo maría Luz Tudela-Serrano Department of Geography Faculty of Geography University of Murcia Campus de la Merced Murcia Spain Department of Agricultural Chemistry Geology and Pedology Faculty of Chemistry University of Murcia Campus de Espinardo Murcia Spain Department of mineralogy and Petrology Faculty of Geology University Complutense of Madrid Madrid Spain

Quarrying of ornamental stone has adverse effects that are both visual and environmental. This paper aims to develop a methodology for minimising the costs associated with reducing the visual impact of ornamental stone quarrying. This study uses digital topographical maps of the study zone and a GPS and GIS application to calculate the extent of the area affected by quarrying activities for each altitude designated in the work plan and to calculate the extent of the potential visual impact. The results obtained applying the proposed methodology for the selected area suggested that the potential visual impact is minimal for an altitude of 520 metres, this being the optimal point for the observer. When altitude increases, the potential visual impact increases and the optimal point for the observer diminishes until the highest impact altitude (740 m) is readied. The optimal point that the exploitation should reach is that at which the values of the diagram generated by the (%) area of potential visual impact and area of exploitation (%) intersect. The methodology allows the optimal altitude to be determined for mining exploitations and helps assess the viability of a given exploitation from an environmental point of view.

关键词： Restoration Costs Ornamental Stone Visual Impact Limestone Quarrying

Biomimetic Synthesized Conductive Copolymer EDOT-Pyrrole Electrodes for Electrocardiogram Recording in Humans

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Journal of materials Science and Chemical Engineering 2021年第10期9卷 19-40页

作者： manuel Eduardo martínez-Cartagena Juan Bernal-martínez Carlos Alberto Aranda-Sánchez Arnulfo Banda-Villanueva josé Luis Gonzalez-Zapata Antonio Ledezma-Pérez Alfredo Aguilar-Elguezabal Jorge Romero-García Advanced materials Department Research Center in Applied Chemistry (CIQA) Saltillo Coahula México Laboratory in Biomedicine and Nanotechnology Aguascalientes Aguascalientes México Department of Reactions Engineering Research Center in Applied Chemistry (CIQA) Saltillo Coahula México Department of Engineering and Chemistry of materials Research Center in Advanced Materials (CIMAV) Chihuahua México

We report on electrodes fabricated with EDOT-Pyrrole copolymer through electrophoretic deposition and used for recording and sensing bio-electrical signals. We measured the electrical properties of the copolymer deposited on a stainless-steel substrate, and we performed Cyclic Voltammetry (CV) and Scanning Electron microscopy (SEm) studies to characterize the morphological properties and copolymer distribution on the metal surface. We found that electrodes fabricated with EDOT-Pyrrole copolymer exhibit a high signal-to-noise ratio as well as an accurate and stable conductivity compared with other commonly used electroconductive polymers. Stainless-steel-coated EDOT-Pyrrole electrodes are suitable to record electrocardiograms in humans with high resolution comparable to standard silver-electrodes.

关键词： Electrocardiogram Bioelectrical Signals Biomimetic Conductive Polymers

Correcting distortions of thin-walled machined parts by machine hammer peening

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Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor mADARIAGA mikel CUESTA Gorka ORTIZ-DE-ZARATE Eneko SAENZ-DE-ARGANDONA Denis SORIANO michael B.PRImE Pedro jose ARRAZOLA Department of materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEm model was used to predict distortions caused by machining in a representative ***,the RS induced by hammer peening were included in an FEm model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 mPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics machining,Hammer Peening Aluminium alloy Distortions Residual Stress

Slip-model Performance for Underexpanded micro-scale Rocket Nozzle Flows

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Journal of Thermal Science 2007年第3期16卷 223-230页

作者： joséA.morí■igo joséHermidaQuesada Francisco Caballero Requena Dept.of Space Programmes Dept.of

In aerospace micro-Electro mechanical Systems （mEmS）, the characteristic length scale of the flow approaches the molecular mean free path, thus invalidating the continuum description and enforcing the use of particle methods, like the Direct Simulation monte Carlo （DSmC）, to deal with the non-equilibrium regions. Within the slip-regime （0.01〈Kn〈-0.1） both approaches, continuum and particle-based, seem to behave well in terms of accuracy. The present study summarizes the implementation and results obtained with a 2nO-order slip boundary condition in a Navier-Stokes solver to address the rarefaction near the nozzle walls. Its assessment and application to a cold-gas micro-scale conical nozzle of 300μm throat diameter, discharging into the low-pressure freestream, constitutes the major aim of the work. The slip-model incorporates the velocity slip with thermal creep and temperature jump, thus permitting to deal with non-isothermal flows as well. Results show that the gas experiences an intense rarefaction in the lip vicinity, pointing to the limits of model validity. Furthermore, a strong mach deceleration is observed, attributed to the rather thick subsonic boundary layer and supersonic bulk heating caused by the viscous dissipation, in contrast with the expansion to occur in large rocket nozzles during underexpanded operation.

关键词： Slip flow mEmS micronozzles

Hydroelectrolytic and Energetic Replenisher in Horses Undergoing marcha Training

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Open Journal of Veterinary medicine 2024年第8期14卷 203-216页

作者： josé D. Ribeiro Filho Bruna m. Ribeiro micheline O. Silva Samuel R. Alves Anaïs C. Benitez Waleska m. F. Dantas marcel F. B. Avanza Raffaella B. C. Teixeira Pedro Ancelmo N. Ermita Laice A. Silva Rinaldo B. Viana Hélio C. manso Filho Department of Veterinary Federal University of Viosa Viosa Brazil Institute of Studies of the Wet Tropic Federal University of Southern and Southeastern Par Xinguara Brazil Department of Veterinary Clinic and Surgery Federal University of Minas Gerais Belo Horizonte Brazil Institute of Animal Health and Production Federal Rural University of Amazonia Belm Brazil Zootecnics Department Federal Rural University of Pernambuco Recife Brazil

The study aimed to assess the clinical, laboratory, and blood gas analysis of horses undergoing marcha training and the effects of voluntary ingestion of hydroelectrolytic and energy replenishers after exercise. Eight horses of both genders aged between 5 and 10 years, were included in the study. The exercise consisted of a 10-min warm-up followed by 45 min uninterrupted marcha on a flat dirt track in the morning. After exercise, the horses received one of the following treatments: Drinking water (control group);Hydroelectrolytic and energy replenisher containing sodium chloride, potassium chloride, calcium acetate, magnesium chloride, sodium citrate, dextrose, maltodextrin, and sucrose in three different concentrations (Replenishers A, B, and C). The horses were distributed across the four treatments in a 4 × 4 Latin Squares design using a Split-plot system with 48-hr intervals. Clinical and laboratory evaluations were conducted at four time points: T0 - 5 min before exercise;T1 - up to 5 min after exercise;T2 - 2 hr after starting treatment;and T4 - 4 hr after beginning treatment. Concentrations of urea, creatinine, lactate, phosphorus, and ionized calcium significantly changed after exercise. An increase in blood pH and a decrease in chloride concentrations were observed when replenishers B and C were offered after exercise. The replacements were ingested spontaneously by the animals in a volume greater than that of the control group (water). Replacement B was the most ingested by the animals, demonstrating its greatest potential.

关键词： Dehydration Electrolyte Replacement Exercise Rehydration Voluntary Intake

Structural Comportment of Extract of Bougainvillea xbuttiana Flower Incorporated in Silica Xerogel matrix

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American Journal of Plant Sciences 2016年第6期7卷 828-833页

作者： josé martínez-mendoza Erika Espericueta-González Diana Espericueta-González Gerardo Ortega-Zarzosa Azdrubal Lobo Guerrero Departamento de Físico-matemáticas Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ciencias Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ingeniería Universidad Autónoma de San Luis Potosí San Luis Potosí México Doctorado Institucional de Ciencia e Ingeniería de materiales Universidad Autónoma de San Luis Potosí San Luis Potosí México Instituto de Física Universidad Autónoma de San Luis Potosí San Luis Potosí México

measurement of the fluorescence comportment of Bougainvillea xbuttiana flowers embedded in silica xerogels matrix prepared with two different water to tetraethyl-orthosilicate [Si(OC2H5)4] ratio molar of 11 and 5, without heat-treatment, we report the grade of biostability of compound. The structural comportment for the PSI and PSII present in Bougainvillea flower is similar to the structural comportment for these photosystems present in leaves when they are incorporated on inorganic matrix such as silica xerogels. The contribution of the natural pigment of this kind of flower such as betalains which consist of betaxanthins and betacyanins, determines their colors contributed in the range of wavelength from about 550 nm to 660 nm.

关键词： Betalaine Chlorophyll Structure Biostability Sol-Gel

molecular isolation and identification of mycobacterium avium *** in Didelphis virginiana from Hidalgo,mexico

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Asian Pacific Journal of Tropical medicine 2020年第3期13卷 131-136页

作者： Nallely Rivero-Perez Juan Ocampo-López Benjamín Valladares-Carranza Fabián R.Gómez de Anda Francisco J.Pena Jiménez Victor m.martínez Juárez Armando Peláez Acero jose I.Olave Leyva Deyanira Ojeda-Ramírez Adrian Zaragoza-Bastida Area Académica de medicina Veterinaria y Zootecnia Instituto de Ciencias AgropecuariaUniversidad Autónoma del Estado de HidalgoAv.Universidad Km 1Ex-Hda.de AquetzalpaC.P.43600 TulancingoHidalgoMéxico Centro de Investigación y Estudios Avanzados en Salud Animal Facultad de Medicina Veterinaria y ZootecniaUniversidad Autónoma del Estado de MéxicoKm 15.5 Carretera Panamericana Toluca-AtlacomulcoC.P.50200 TolucaEstado de MéxicoMéxico Centro Universitario del Sur/División de Ciencias de la Salud/Departamento de Ciencias Clínicas/Hospital Veterinario CUSUR Universidad de Guadalajara Av.Enrique Arreola Silva No.883colonia centro C.P.49000Ciudad GuzmánJaliscoMéxico

Objective:To isolate and identify the exact species of the genus mycobacterium from Didelphis(D.)virginiana,and the direct implications of this bacterium to public health and veterinary ***:Thirty-one *** were captured and necropsied in Hidalgo,*** samples were collected to culture mycobacteria present and examine individual specimens’*** identification was obtained through the application of amplification and sequencing of 16S rDNA ***:Three strains were isolated and identified as mycobacterium(m.)avium *** by utilizing *** complexspecific *** lesions were observed in the subpleural zone(granuloma gradeⅡ)and bronchial(granuloma gradeⅠ)of the lungs of *** with positive ***:Three strains of *** ***,from lung tissue samples of *** were *** subspecies of *** has important implications in public health and veterinary medicine.

关键词： Didelphis virginiana mycobacterium avium complex mycobacterium avium subsp.hominissuis Public health

Thermo-Stability of Natural Products Based on Chlorophyll Species Embedded in Silica Xerogel

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American Journal of Analytical Chemistry 2016年第4期7卷 356-362页

作者： josé martínez-mendoza Erika Espericueta-González Diana Espericueta González Gerardo Ortega-Zarzosa Azdrubal Lobo Guerrero Departamento de Físico-matemáticas Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ciencias Universidad Autónoma de San Luis Potosí San Luis Potosí México Facultad de Ingeniería Universidad Autónoma de San Luis Potosí San Luis Potosí México Doctorado Institucional de Ciencia e Ingeniería de materiales Universidad Autónoma de San Luis Potosí San Luis Potosí México Instituto de Física Universidad Autónoma de San Luis Potosí San Luis Potosí México

This work studied the thermostability and the biostability of chlorophyll species obtained from an extract of spinach leaves embedded in a silica xerogel matrix. The analysis was done by monitoring the photosystem II (PSII) using fluorescence spectroscopy. Samples were prepared using the sol gel method with a molar ratio of ethanol/H2O/TEOS of 4:11.6:1. Then, silica xerogel matrix was loaded with an extract of spinach leaves, obtained in dark conditions. The measurement of the fluorescence spectra was done at selected temperatures to the corresponding non-physiological regimen. Results indicate that the PSII band position remains unchanged when heat treatment temperature increases up 200°C. For temperatures above 100?C, the fluorescence intensity diminishes linearly when the temperature increases. The photosystem II embedded in silica xerogel matrix is decomposed at temperatures above 200°C.

关键词： Chlorophyll Structure Biostability Sol-Gel