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Woody plant taxonomic,functional,and phylogenetic diversity decrease along elevational gradients in Andean tropical montane forests:Environmental filtering and arrival of temperate taxa

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Plant Diversity 2024年第4期46卷 491-501页

作者： Guillermo Bañares-de-Dios Manuel J.Macía gabriel Arellano Íñigo Granzow-de la Cerda Julia Vega-álvarez Itziar Arnelas Carlos I.Espinosa Norma Salinas Luis Cayuela Departamento de Biología y Geología Física y Química InorgánicaUniversidad Rey Juan CarlosCalle Tulipán s/nMóstolesMadridES-28933Spain Departamento de Biología Área de BotánicaUniversidad Autónoma de MadridCalle Darwin 2MadridES-28049Spain Centro de Investigación en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autónoma de MadridCalle Darwin 2MadridES-28049Spain Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109USA Oikobit LLC ***AlbuquerqueNM87120USA Real Jardín Botánico–CSIC Plaza Murillo 2MadridES-28014Spain Departamento de Biología Animal EcologíaParasitologíaEdafología y Química AgrícolaUniversidad de SalamancaCalle Donantes de Sangre s/nSalamancaES-37007Spain Departamento de Biodiversidad Ecología y EvoluciónUniversidad Complutense de MadridCalle JoséAntonio Nováis 12Ciudad UniversitariaES-28040Spain Departamento de Ciencias Biológicas y Agropecuarias Universidad Técnica Particular de LojaA.P.11-01-608 LojaEcuador Sección Química Pontificia Universidad Católica del PerúA.P.Lima 32LimaPeru ECI School of Geography and EnvironmentUniversity of OxfordOX13QYOxfordshireUnited Kingdom Instituto de Investigación en Cambio Global(IICG-URJC) Universidad Rey Juan CarlosCalle Tulipán s/nMóstolesMadridES-28933Spain

Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short *** research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients,but other facets should be *** first time,we simultaneously assessed elevational trends in taxonomic,functional,and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary *** investigation covered four transects(traversing ca.2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range(ca.10°).Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic,functional,and phylogenetic diversity as elevation increased,although the decrease was less pronounced for higher Hill *** exception was a slight increase in phylogenetic diversity when dominant species were *** decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands,where the increasingly harsher conditions exclude species and functional ***,the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional *** phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate *** could be explained by a decreasing presence and abundance of temperate,extratropical taxa towards the central Andes relative to northern or southern Andes,where they are more prevalent.

关键词： Altitudinal gradients Andes Environmentalﬁltering Out of the Tropical Lowlands Functional rarity Tropical Niche Conservatism

Structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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Journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A García-murillo A Carrillo-Romo F de J Cruz-Santiago L A Chadeyron G morales-Ramírez A de J Velumani S T.A. Post-graduate Student. Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F Departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de Chimie de Clermont-Ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France Department of Electrical Engineering (SEES) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, LCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with FT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the Scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

磺酸多相催化剂用于二甲基亚砜中C_6-单糖脱水制5-羟甲基糠醛(英)

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催化学报 2014年第5期35卷 644-655页

作者： gabriel morales Juan A.Melero Marta Paniagua Jose Iglesias Blanca Hernandez Maria Sanz Department of Chemical and Environmental Technology Universidad Rey Juan Carlos. C/Tulipan s/n. Mostoles. E28933Madrid Spain Department of Chemical and Energy Technology Universidad Rey Juan Carlos. C/Tulipan s/n. Mostoles. E28933 Madrid Spain

Sulfonic acid-functionalized heterogeneous catalysts have been evaluated in the catalytic dehydration of C(,monosaccharides into 5-hydroxymethylfurfural(HMF) using dimethyl sulfoxide(DMSO)as *** commercial resin Amberlyst-70 was the most active catalyst,which was ascribed to its higher concentration of sulfonic acid sites as compared with the other catalysts,and it gave 93 mol%yield of HMF from fructose in 1 *** glucose as the starting material,which is a much more difficult reaction,the reaction conditions(time,temperature,and catalyst loading) were optimized for Amberlyst-70 by a response surface methodology,which gave a maximum HMF yield of 33 mol%at 147 °C with 23 wt%catalyst loading based on glucose and 24 h reaction *** promotes the dehydration of glucose into anhydroglucose,which acts as a reservoir of the substrate to facilitate the production of HMF by reducing side *** reuse without a regeneration treatment showed a gradual but not very significant decay in catalytic activity.

关键词：非均相催化剂羟甲基糠醛二甲基亚砜磺酸脱水单糖响应面分析法 DMSO

A POSTERIORI ERROR ANALYSIS OF A FULLY-MIXED FINITE ELEMENT METHOD FOR A TWO-DIMENSIONAL FLUID-SOLID INTERACTION PROBLEM

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Journal of Computational Mathematics 2015年第6期33卷 606-641页

作者： Carolina Dominguez gabriel N. Gatica salim meddahi Instituto de Ciencias Fisicas y Matemdticas facultad de ciencias universidad austral de chile Avenida Eduardo morales Miranda - Campus isla teja valdivia chile CI2 MA and Departamento de Ingenieria Matematica Universidad de concapcion casilla 160 concepcion chile Departamento de Matemdticas Facultad de ciencias universidad de oiede calvo satela s/n oviedo espana

In this paper we develop an a posteriori error analysis of a fully-mixed finite element method for a fluid-solid interaction problem in 2D. The media are governed by the elas-todynamic and acoustic equations in time-harmonic regime, respectively, the transmission conditions are given by the equilibrium of forces and the equality of the corresponding normal displacements, and the fluid is supposed to occupy an annular region surrounding the solid, so that a Robin boundary condition imitating the behavior of the sommerfeld condition is imposed on its exterior boundary. Dual-mixed approaches are applied in both domains, and the governing equations are employed to eliminate the displacenent a of the solid and the pressure p of the fluid. In addition, since both transmission conditions become essential, they are enforced weakly by means of two suitable lahrange multipliers The unknowns of the solid and the fluid are then approximated by a conforming galerkin scheme defined in terms of PEERS elements in the solid, Raviart-Thomas of lowest order in the fluid, and continuous piecewise linear functions on the boundary, As the main con-tribution of this work, we derive a reliable and efficient residual-based a posteriori error estimator for the aforedescribed coupled problem. Some numerical results confirming the properties of the estimator are also reported.

关键词： Mixed finite elements Helmholtz equation Elastodynamic equation A poste- riori error analysis

Evaluation of Optical Localization in the Visible Band for Ultrasound Guidance in Radiotherapy Using A Robotic Arm

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肿瘤预防与治疗 2017年第5期30卷 319-329页

作者： Saskia Camps Matilde Costa Ester Stevens Pedro Gomes Sanches gabriel Paiva Fonseca murillo Bellezzo Frank Verhaegen Davide Fontanarosa Faculty of Electrical Engineering University of Technology Eindhoven Oncology Solutions Department Philips ResearchHigh Tech Campus 34 Department of Radiation Oncology ( MAASTRO) GROW-School for Oncology and Developmental BiologyMaastricht University Medical Center School of Clinical Sciences Queensland University of TechnologyGardens Point campus

In many medical fields,spatial localization of devices is of paramount importance to *** treatments correctly or to perform accurate diagnostic *** the different technologies available,optical localization in the visible band of the spectrum offers many advantages:minimum interference with other instruments,flexibility in position of the devices used and extra features such as patient/operator surface tracking or vital signs *** application in the domain of radiotherapy is novel,and potentially very *** this work we introduced a workflow to test the reliability of one of these systems,developed in house,to localize an ultrasound transducer for ultrasound guided radiation therapy(USg RT).Accuracy,precision,latency,sensitive volume and sensitivity to light intensity were *** workflow we proposed allowed us to establish that,while all the clinically relevant parameters of the system are acceptable,accuracy in locating the transducer could be as intended purpose of the system.

关键词：肿瘤学预防医学临床治疗症状

Extreme Adaptation to Extreme Environments in Hot Dry, Hot Sub-humid and Hot Humid Climates in Mexico

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Journal of Civil Engineering and Architecture 2014年第8期8卷 929-942页

作者： Luis gabriel Gomez-Azpeitia Gonzalo Bojorquez-morales Raul Pavel Ruiz Irene Marincic Eduardo Gonzalez Adalberto Tejeda Faculty of Architecture and Design University of Colima Coquimatlan 28040 Mexico Faculty of Architecture Autonomic University of Baja California Mexicali 21101 Mexico Faculty of Architecture Autonomic University of Chiapas Tuxtla Gutierrez 29050 Mexico Architecture and Design Department University of Sonora Hermosillo 83000 Mexico Faculty of Architecture and Design University of Zulia Maracaibo 4011 Venezuela Faculty of Electronic and Atmospheric Sciences Instrumentation Veracruz University Xalapa 91090 Mexico

The paper discusses the results of a field study carried out in four cities in Mexico： Hermosillo, Mexicali, Merida and Colima, during the warmest seasons of 2006-2007. The survey is according to the adaptive approach of thermal comfort. The cities＇ climates are hot dry, hot sub-humid and hot humid. The respondents were inhabitants of low cost housings without air conditioning. The research was performed during warm seasons and according to ISO 10551. The measurements were processed by the common method of linear regression and also by alternative methods, useful for asymmetric climates. Individuals declared comfort at very high temperatures, either high or low humidity, therefore, the resulting neutral temperatures are higher than 30 ℃, except in Colima （28.8 ℃）. The upper limits of comfort ranges achieved temperatures up to 35 ℃. The results suggest how great is the capacity of humans to adapt to conditions as extreme as those measured in the study.

关键词： Acclimation thermal comfort adaptive approach field studies

ATMOSPHERIC TRACE METAL MEASUREMENTS OF AIR PARTICULATE lN SOUTHERN PUERTO RICO

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ATMOSPHERIC TRACE METAL MEASUREMENTS OF AIR PARTICULATE lN S...

Photomechanical Ablation of 304L Stainless Steel, Aluminum Oxide (Al₂O₃) Thin Film, and Pure Silicon

40th IUPAC Congress

作者： gabriel A Infante Sheila Vquez Daisy morales Jaime Prez Anderson Monmlvo Rev.T. Giangiacomo Scientific Research Center.Pontifical Catholic University ofPuerto Rico PoncePR 00717-9997 Rev.T. Giangiacomo Scientific Research Center.Pontifical Catholic University ofPuerto Rico PoncePR 00717-9997 Rev.T. Giangiacomo Scientific Research Center.Pontifical Catholic University ofPuerto Rico PoncePR 00717-9997 Rev.T. Giangiacomo Scientific Research Center.Pontifical Catholic University ofPuerto Rico PoncePR 00717-9997 Rev.T. Giangiacomo Scientific Research Center.Pontifical Catholic University ofPuerto Rico PoncePR 00717-9997

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Optics and Photonics Journal 2016年第10期6卷 275-288页

作者： gabriel de la Rosa-Santana Jose Alfredo Alvarez-Chavez Hector R. Morano-Okuno Angel J. morales-Ramirez Esmeralda Uribe Instituto Tecnologico y de Estudios Superiores de Monterrey Campus Estado de Mexico Atizapan de Zaragoza Mexico Instituto Politecnico Nacional-Centro de Investigacion e InnovacionTecnologica (CIITEC-IPN) Mexico City Mexico Instituto Tecnologico y de Estudios Superiores de Monterrey Campus Queretaro Santiago de Queretaro Mexico

Recently, a number of studies have focused on micro-manufacturing processes, which find use in a variety of applications, including the production of microelectromechanical systems (MEMS). The process of ablation in materials is mainly governed by the laser source and scanning speed. The rate of material ablation is influenced by chemical and physical properties. In this work, the energy from a CO2 laser was used to ablate three different materials, namely, stainless steel 304L, a thin film of amorphous aluminum oxide (Al2O3), and pure silicon, due to their wide use in MEMS technology. The laser parameters used were an average power of 18 W and a spot size of 200 μm. The maximum depth during the photomechanical ablation process was 72 μm in the case of 304L steel and 77 μm in the case of the Al2O3 thin film for a scan rate of 24 mm/min. However, at the same scan rate, silicon did not exhibit any penetration. As expected, while increasing scanning speed the ablation depth decreases due to reduced interaction time between laser and material. The theoretical ytterbium fiber laser shown in this study can thus be employed in the manufacturing of a wide variety of materials used in the production of MEMS as well as those used in clean energy technologies.

关键词： Laser Ablation MEMS Ytterbium-Doped Fiber Laser Thin Film

Ca^(2+)-亚氨二醋酸金属离子亲和色谱法吸附内毒素(英文)

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色谱 2012年第11期30卷 1194-1202页

作者： André Moreni LOPES Jorge Sánchez ROMEU Rolando Páez MEIRELES gabriel Marquez PERERA Rolando Perdomo morales Adalberto PESSOA Lourdes Zumalacárregui CáRDENAS Department of Biochemical and Pharmaceutical Technology School of Pharmaceutical SciencesUniversity of So Paulo(FCF/USP) Purification Development Department Center for Genetic Engineering and Biotechnology(CIGB) Center for Pharmaceuticals Research and Development(CIDEM) Higher Polytechnic Institute José Antonio Echeverría(CUJAE)

Endotoxins(also known as lipopolysaccharides(LPS)) are undesirable by-products of recombinant proteins,purified from Escherichia *** can be considered stable under a wide range of temperature and pH,making their removal one of the most difficult tasks in downstream processes during protein *** inherent toxicity of LPS makes their removal an important step for the application of these proteins in several biological assays and for a safe parenteral *** metal affinity chromatography(IMAC) enables the affinity interactions between the metal ions(immobilized on the support through the chelating compound) and the target molecules,thus enabling high-efficiency separation of the target molecules from other components present in a *** chromatography is applied with Ca2+-iminodiacetic acid(IDA) to remove most of the LPS contaminants from the end product(more than90%).In this study,the adsorption of LPS on an IDA-Ca2+ was *** adsorption Freundlich isotherm of LPS-IDA-Ca2+ provides a theoretical basis for LPS *** was found that LPS is bound mainly by interactions between the phosphate group in LPS and Ca2+ ligands on the *** factors such as pH(4.0 or 5.5) and ionic strength(1.0 mol/L) are essential to obtain effective removal of LPS for contaminant levels between endotoxin' concentration values less than100 EU/mL and 100 000 EU/*** new protocol represents a substantial advantage in time,effort,and production costs.

关键词： immobilized metal affinity chromatography(IMAC) lipopolysaccharides(LPS) endotoxin removal recombinant proteins isotherms protein purification