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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

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Preparation of neodymium-doped yttrium aluminum garnet powders and fibers

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Journal of Rare Earths 2008年第5期26卷 670-673页

作者： R. López J. Zárate E. A. Aguilar J. Muoz-Saldaa Instituto de investigaciones Metalurgicas UMSNH Morelia centro de investigación y de estudios avanzados del ipn Unidad Queretaro

Using nitrate precursors, a novel spray-drying assisted citrate gel process for the preparation of neodymium-doped yttrium alumi- num garnet （yAG） phase was developed. Synthesis of single-phase polycrystalline yAG was achieved at temperatures as low as 800 ℃ using the spray-drying methodology whilst conventional approaches currently available require 1000 ℃. Initially, a solution was prepared by mixing aluminum and yttrium nitrates, citric acid, etilenglycol and neodymium oxide. This solution was dried by pulverization （spray dryer） to obtain aggregated precursor powders of the compound. These aggregates were calcined at 800, 850 and 900 ℃ to determine the phase evolution from amorphous to crystalline by X-ray diffraction （XRD）. The morphology of aggregates was characterized by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Moreover, through XRD it was determined that the crystallization of yAG phase started at about 800 ℃ without any intermediate phases. The powders were composed of spherical aggregates with an average diameter of 1 um. From these powders, ceramic fibers with additions of 2at.% and 5at.% nd, were extracted from the melt with diameters ranging from 30 um to 50 um.

关键词： spray-drying melt extraction fibers yttrium aluminum garnet rare earths

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Vanadium mineralization at Los Chihuidos sediment-hosted Cu-V deposit,neuquén Basin,Argentina:An approach to vanadium ore forming processes

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Geoscience Frontiers 2024年第1期15卷 225-246页

作者： Ana L.Rainoldi Daniel Beaufort Marta B.Franchini Adolfo Giusiano Sabine Petit Patricia Patrier M.Josefina Pons Dpto.de Geología Universidad Nacional del Sur(UNS)8000 Bahía BlancaArgentina Consejo nacional de investigaciones Científicas y Técnicas Centro Patagónico de Estudios MetalogenéticosArgentina Universitéde Poitiers IC2MPCNRS-UMR 7285HydrasaF-86022 Poitiers CedexFrance Universidad nacional del Comahue Facultad de IngenieríaDepartamento de Geología y Petróleo8300 NeuquénArgentina Consultant Geologist 8300 NeuquénArgentina Universidad nacional de Río negro Instituto de Investigación en Paleobiología y GeologíaRío NegroArgentina

Vanadium mineralization at Los Chihuidos deposit of the neuquén Basin is linked to the development of a redox front system related to the inflow of hydrocarbons into the red sandstone of the Huincul *** of hydrocarbons with oxidized red beds and connate water generated redox reactions where hematite was dissolved due to iron reduction resulting in the discoloration of the red *** the contact between oxidized red sandstone and reduced white sandstone,precipitation of specific mineral phases resulted in the V ore with minor amounts of *** the implementation of the redox interface,abundant V-montmorillonite and V-hematite precipitated at the more oxidizing conditions and Cu-V-corrensite-type at the more reducing conditions of the redox *** the redox front advanced with fluids constantly migrating into the reservoir,more reducing conditions were stablished,promoting chloritization and minor illitization with V-Cu incorporation and continuous upgrading of the *** ore mineralogy consists of clay minerals including V-bearing montmorillonite,Cu-V-corrensite-type,V-di-trioctahedral chlorite and Cu-tri-trioctahedral chlorite with minor V-illite-smectite mixed-layer minerals and associated secondary *** over illitization was favored due to high amounts of Fe and Mg in detrital clasts and in connate fluids and by low K availability related to low amounts of detrital *** spatial transition of V and/or Cu bearing clay minerals observed through the mineralized redox front at Los Chihuidos deposit(kaolinite→smectite→illite/smectite→corrensite-type→di-trioctahedral-chlorite→tri-trioctahedral-chlorite)and the related variation of V-Cu concentrations in bulk rock are indicative of increasing pH and decreasing Eh of resident solutions from red to white sandstones during the hypogene mineralization *** influx of Cu-rich oxidized basinal brines precipitated main copper ore with Cu-sulfides in the white sandst

关键词： Clay minerals V-chlorite Redox front Bleaching Hydrocarbons

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Preparation and Characterization of Flexible, Transparent and Thermally Stable Aromatic Co-polyamides

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Chinese Journal of Polymer Science 2019年第2期37卷 136-141页

作者： José Antonio Tec-Sánchez Andrés Iván Oliva Arias Manuel Aguilar-Vega Juan Valerio Cauich-Rodríguez José Luis Santiago-García Unidad de Materiales Centro de Investigación Científica de Yucatán A. C. centro de investigación y de estudios avanzados del ipn Unidad Mérida Departamento de Física Aplicada

Two aromatic co-polyamides were synthesized combining two diacid monomers containing bulky pendant groups, 5-(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)isophthalic acid(deAIA) and 5-tert-butylisophthalic acid(TERT), with 4,4′-(hexafluoroisopropylidene)dianiline(HFA) or 2,3,5,6-tetramethyl-1,4-phenylenediamine(Durene) by direct polycondensation. The structures of the obtained aromatic co-polyamides were confirmed by FTIR, Raman and 1 H-nMR. The co-copolyamide films, DHTH and DDTD, exhibited rms-roughness values between 0.94 and 1.60 nm, respectively. Moreover, they presented good thermal stability up to300 °C. young's moduli of the co-polyamide films were between 4.1 and 4.3 GPa. X-ray diffraction results showed that the co-polyamide films were amorphous due to the incorporation of both bulky pendant groups, tert-butyl and dibenzobarrelene. The combination of bulky pendant groups provided intrinsically transparent co-polyamide films with a transmittance higher than 88% in the range of 400-780 *** to these outstanding film and optical properties, they are suggested to be flexible substrates in applications for solar cell and other portable electronic devices.

关键词： Co-polyamides Flexible films Transmittance Thermal stability Polycondensation

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Influence of Angiotensin II on α₁-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells

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Journal of Biosciences and Medicines 2024年第4期12卷 123-134页

作者： Itzell Alejandrina Gallardo-Ortíz Juan Pablo de Jesús Benítez-Garrido Santiago C. Sigrist-Flores Juan Javier López-Guerrero Enrique Hong Rafael Villalobos-Molina Unidad de Biomedicina Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico Carrera de Enfermerí a Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico departamento de Farmacobiologí a Centro de Investigaci&#243n and de Estudios Avanzados-IPN Ciudad de M&#233xico M&#233xico Carrera de Mé dico Cirujano Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico

Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT1 and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of Ang II on the expression and function of α1-adrenergic receptors (α1-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24 h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. Ang II was added (1 × 10−5 M), and in some experiments, 5-Methylurapidil (α1A-AR antagonist), AH11110A (α1B-AR antagonist), or BMy-7378 (α1D-AR antagonist), were used to identify the α1-AR involved in the response. desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the Ang II action. α1D-AR was protected from desensitization by BMy-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to Ang II and α1-ARs proteins were evaluated. α1D-AR increased at 30 and 60 min post Ang II exposure, the α1A-AR diminished from 1 to 4 h, while α1B-AR remained unchanged over 24 h of Ang II exposure. Ang II induced an increase of α1D-AR at short times, and BMy-7378 protected α1D-AR from desensitization.

关键词： Angiotensin II α1D-AR α1-AR Expression Rat aorta Smooth Muscle Cells

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road to stemness in hepatocellular carcinoma

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World Journal of Gastroenterology 2017年第37期23卷 6750-6776页

作者： Teresita nJ Flores-Téllez Saúl Villa-Trevino Carolina Pina-Vázquez departam ento de Biología Celular Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV-IPN) Av.IPN No.2508 Col

Carcinogenic process has been proposed to relay on the capacity to induce local tissue damage and proliferative repair. Liver has a great regeneration capacity and currently, most studies point towards the dominant role of hepatocytes in regeneration at all levels of liver damage. The most frequent liver cancer is hepatocellular carcinoma(HCC). Historical findings originally led to the idea that the cell of origin of HCC might be a progenitor cell. However, current linage tracing studies put the progenitor hypothesis of HCC origin into question. In agreement with their dominant role in liver regeneration, mature hepatocytes are emerging as the cell of origin of HCC, although, the specific hepatocyte subpopulation of origin is yet to be determined. The relationship between the cancer cell of origin(CCO) and cancer-propagating cells, known as hepatic cancer stem cell(HCSC) is unknown. It has been challenging to identify the definitive phenotypic marker of HCSC, probably due to the existence of different cancer stem cells(CSC) subpopulations with different functions within HCC. There is a dynamic interconversion among different CSCs, and between CSC and non-CSCs. Because of that, CSC-state is currently defined as a description of a highly adaptable and dynamic intrinsic property of tumor cells, instead of a static subpopulation of a tumor. Altered conditions could trigger the gain of stemness, some of them include: EMT-MET, epigenetics, microenvironment and selective stimulus such as chemotherapy. This CSC heterogeneity and dynamism makes them out reach from therapeutic protocols directed to a single target. A further avenue of research in this line will be to uncover mechanisms that trigger this interconversion of cell populations within tumors and target it.

关键词： Cancer stem cell Liver progenitor cell Liver stem progenitor cell Stemness Plasticity Cancer cell of origin Cancer stem cells subpopulations

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Microstructural evaluation and nanohardness of an AlCoCuCrFeniTi high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 634-641页

作者： C.D.Gómez-Esparza R.Peréz-Bustamante J.M.Alvarado-Orozco J.Mu?oz-Salda?a R.Martínez-Sánchez J.M.Olivares-Ramírez A.Duarte-Moller centro de investigación en Materiales avanzados (CIMAV) Laboratorio Nacional de Nanotecnología COnACyT-Corporación Mexicana de investigación en Materiales S.A.de C.V.(COMIMSA) centro de Ingeniería y desarrollo Industrial Querétaro Campus centro de investigación y de estudios avanzados del ipn Unidad Querétaro Universidad Tecnológica de San Juan del Río Escuela de Ingeniería Civil Industrialy Mecánica Universidad De La Salle Bajío

An AlCoCuCrFeniTi high-entropy alloy(HEA) was prepared by mechanical alloying and sintering to study the effect of Ti addition to the widely studied AlCoCuCrFeni system. The structural and microstructural characteristics were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), and transmission electron microscopy(TEM). The formation of four micrometric phases was detected: a Cu-rich phase with a face-centered cubic(fcc) structure, a body-centered cubic(bcc) solid solution with Cu-rich plate-like precipitates(fcc), an ordered bcc phase, and a tetragonal structure. The XRD patterns corroborate the presence of a mixture of bcc-, fcc-, and tetragonal-structured phases. The Vickers hardness of the alloy under study was more than twice that of the AlCoCuCrFeni alloy. nanoindentation tests were performed to evaluate the mechanical response of the individual phases to elucidate the relationship between chemical composition, crystal structure, and mechanical performance of the multiphase microstructure of the AlCoCuCrFeniTi HEA.

关键词： high-entropy alloys mechanical alloying microstructure nanoindentation

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A versatile microfluidic device for multiple ex vivo/ in vitro tissue assays unrestrained from tissue topography

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Microsystems & nanoengineering 2020年第1期6卷 806-819页

作者： Jose M.de Hoyos-Vega Alan M.Gonzalez-Suarez Jose L.Garcia-Cordero Unidad Monterrey Centro de Investigacion y de Estudios Avanzados del IPNVia del conocimiento 201Parque PIITApodacaNL 66628Mexico

Precision-cut tissue slices are an important in vitro system to study organ function because they preserve most of the native cellular microenvironments of organs,including complex intercellular ***,during sample manipulation or slicing,some of the natural surface topology and structure of these tissues is lost or ***,we introduce a microfluidic platform to perform multiple assays on the surface of a tissue section,unhindered by surface *** device consists of a valve on one side and eight open microchannels located on the opposite side,with the tissue section sandwiched between these two *** the valve is actuated,eight independent microfluidic channels are formed over a tissue *** strategy prevents cross-contamination when performing assays and enables *** irregular tissues such as an aorta,we conducted multiple in vitro and ex vivo assays on tissue sections,including short-term culturing,a drug toxicity assay,a fluorescence immunohistochemistry staining assay,and an immune cell assay,in which we observed the interaction of neutrophils with lipopolysaccharide(LPS)-stimulated *** microfluidic platform can be employed in other disciplines,such as tissue physiology and pathophysiology,morphogenesis,drug toxicity and efficiency,metabolism studies,and diagnostics,enabling the conduction of several assays with a single biopsy sample.

关键词： metabolism topography versatile

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nano to micro size transition of hydroxyapatite in porcine bone during heat treatment with low heating rates

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Progress in natural Science:Materials International 2020年第4期30卷 494-501页

作者： Angélica M.Castillo-Paz Sandra M.Londo?o-Restrepo Liliana Tirado-Mejía M.A.Mondragón Mario E.Rodríguez-García Grupo de Optoelectrónica Instituto Interdisciplinario de las Ciencias Universidad del Quindío centro de investigación y de estudios avanzados del ipn departamento de nanotecnología Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla

This work focuses on the changes of raw hydroxyapatite obtained from porcine bones during heat treatment with heating rates of 2.5 and 5.0 °C/min between 600 °C and 1100 °C. High-Resolution transmission electron microscopy(HR-TEM) images showed that raw hydroxyapatite was formed by high-ordered nanometric platelet crystals with a length of around 18 nm and width around 7 nm. High-Resolution scanning electron microscopy(HR-SEM) images evidenced the coalescence phenomena during heating giving. It was found that the growth of the crystals and the transition from nano to a micro-size occurred at around 700 °C. And the changes in the full width at half maximum(FWHM) for the characteristic(002) plane of the X-ray diffraction patterns and the FWHM of the characteristic Raman band at 960 cm-1 for ν1 PO43-exhibited the transition from nano to a micro size, that was confirmed by HR-SEM images and the thermogravimetric(TG) analysis. The porosity of the BIOHAp changes from intra nanometric to intercrystalline.

关键词： Bone composition Hydroxyapatite nanoparticles Mineral composition Porosity formation Raman analysis

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Tale of two kinases:Protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ in pre-diabetic cardiomyopathy

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World Journal of Diabetes 2021年第10期12卷 1704-1718页

作者： Pamela Gaitán-González Rommel Sánchez-Hernández José-Antonio Arias-Montaño Angélica Rueda department of Biochemistry Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalCiudad de México 07360Mexico department of Physiology Biophysics and NeurosciencesCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalCiudad de México 07360Mexico

Metabolic syndrome is a pre-diabetic state characterized by several biochemical and physiological alterations,including insulin resistance,visceral fat accumulation,and dyslipidemias,which increase the risk for developing cardiovascular *** syndrome is associated with augmented sympathetic tone,which could account for the etiology of pre-diabetic *** review summarizes the current knowledge of the pathophysiological consequences of enhanced and sustainedβ-adrenergic response in pre-diabetes,focusing on cardiac dysfunction reported in diet-induced experimental models of pre-diabetic *** research reviewed indicates that both protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ play important roles in functional responses mediated byβ1-adrenoceptors;therefore,alterations in the expression or function of these kinases can be *** review also outlines recent information on the role of protein kinase A and Ca^(2+)/calmodulin-dependent protein kinase Ⅱ in abnormal Ca^(2+)handling by cardiomyocytes from diet-induced models of pre-diabetic cardiomyopathy.

关键词： Ca^(2+)/calmodulin-dependent protein kinase II Protein kinase A Metabolic syndrome Pre-diabetes Pre-diabetic cardiomyopathy β-Adrenoceptors

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