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Provenance of sediments from Barra del Tordo and Tesoro beaches, Tamaulipas State, northwestern Gulf of Mexico

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Journal of Palaeogeography 2021年第3期10卷 382-398页

作者： Mayla A.Ramos-vazquez John S.Armstrong-Altrin Posgrado en Ciencias del Mar y Limnologpa Universidad Nacional Autonoma de MexicoCiudad UniversitariaCiudad de Mexico 04510Mexico Universidad Nacional Autonoma de Mexico Instituto de Ciencias del Mar y LimnologiaUnidad de Procesos Oceanicos y CosterosCiudad UniversitariaCiudad de Mexico 04510Mexico

The mineralogy, bulk sediment geochemical composition, and U–Pb ages of detrital zircons retrieved from the Barra del Tordo(Tordo) and Tesoro beach sediments in the northwestern Gulf of Mexico were analyzed to determine their provenance. The beach sediments are mainly composed of quartz, ilmenite, magnetite, titanite,zircon, and anorthite. The weathering proxies such as the Chemical Index of Alteration(CIA), Chemical Index of Weathering(CIW), and Plagioclase Index of Alteration(PIA), reveal a moderate-to-high intensity of weathering in the source area. The chondrite-normalized rare earth element(REE) patterns are similar to felsic igneous rocks, with large negative europium anomaly(Eu/Eu^(*)= ~ 0.47–0.80 and ~ 0.57–0.67 in the Tordo and Tesoro beach sediments,respectively).Three major zircon U–Pb age groups are identified in the Tordo and Tesoro beach sediments, i.e., Proterozoic(~2039–595 Ma), Mesozoic(~ 244–70.3 Ma), and Cenozoic(~ 65.9–1.2 Ma). The differences of the zircon age spectrum between the Tordo and Tesoro beach sediments are not significant. The comparison of zircon U–Pb ages in this study with ages of potential source terranes suggests that the Mesozoic and Cenozoic zircons of the studied Tordo and Tesoro beach sediments were derived from the Eastern Alkaline Province(EAP) and Mesa Central Province(MCP). Similarly, the likely sources for the Proterozoic zircons were the Sierra Madre Oriental(SMOr) and Oaxaquia in the northwestern Gulf of Mexico. The results of this study further indicate that the sediments delivered to the beaches by rivers and redistributed by longshore currents were crucial in determining the sediment provenance.

关键词： Geochemistry Sedimentary provenance Zircon U–Pb Beach sediment Rare earth elements Mexico

Analysis of correlated data with feedback for time-dependent covariates in psychiatry research

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General Psychiatry 2020年第5期33卷 374-377页

作者： Elsa vazquez Arreola Jeffrey R Wilson Ding-Geng Chen School of Mathematical and Statistical Sciences Arizona State UniversityTempeArizonaUSA Department of Economics W.P.Carey School of BusinessArizona State UniversityTempeArizonaUSA School of Social Work and Department of Biostatistics University of North Carolina at Chapel HillChapel HillNorth CarolinaUSA

In studies on psychiatry and neurodegenerative diseases,it is common to have data that are correlated due to the hierarchical structure in data collection or to repeated measures on the subject ***,the feedback effect created due to time-dependent covariates in these studies is often overlooked and seldom *** article reviews the methodological development of feedback effects with marginal models for longitudinal data and discusses their implementation.

关键词： diseases psy measures

Role of artificial intelligence in cardiology

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World Journal of Cardiology 2023年第4期15卷 116-118页

作者： Rafael Vidal-Perez Jose Manuel vazquez-Rodriguez Servicio de Cardiología Unidad de Imagen y Función CardíacaComplexo Hospitalario Universitario A Coruña Centro de Investigación Biomédica en Red-Instituto de Salud Carlos ⅢA Coruña 15006A CoruñaSpain Servicio de Cardiología Complexo Hospitalario Universitario A CoruñaA Coruña 15006A CoruñaSpain

Artificial intelligence(AI)is the process of having a computational program that can perform tasks of human intelligence by mimicking human thought *** is a rapidly evolving transdisciplinary field which integrates many elements to develop algorithms that aim to simulate human intuition,decision-making,and object *** overarching aims of AI in cardiovascular medicine are threefold:To optimize patient care,improve efficiency,and improve clinical *** cardiology,there has been a growth in the potential sources of new patient data,as well as advances in investigations and therapies,which position the field well to uniquely benefit from *** this editorial,we highlight some of the main research priorities currently and where the next steps are heading us.

关键词： Artificial intelligence Machine learning Deep learning Electrocardiography Cardiac imaging

Kinetic study of austenite formation during continuous heating of unalloyed ductile iron

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 27-31页

作者： Octvio vazquez-Gómez Jos Antonio Barrera-Godínez Hctor Javier Vergara-Hernndez Faculty of Chemistry Metallurgical Engineering DepartmentAutonomous National University of Mexico Metallurgy Science Postgraduate Programme Morelia Institute of Technology

The austenite formation kinetics in unalloyed cast ductile iron was studied on the basis of dilatometry measurements, and Avrami＇s equation was used to estimate the material＇s kinetic parameters. A continuous heating transformation diagram was constructed us-ing heating rates in the range of 0.06 to 0.83℃·s^-1. As the heating rate was augmented, the critical temperatures, c1A and Aα, as well as the intercritical range, which was evaluated as the difference between the critical temperatures, α c1Δ T =A_a- A_c1 , increased. At a low heating rate, the kinetics of austenite formation was slow as a consequence of the iron＇s silicon content. The effect of heating rate on k and n, the kinetic parameters of Avrami＇s equation, was also determined. Parameter n, which is associated with nucleation sites and growth geometry, de-creased with an increase in heating rate. In addition, parameter k increased with the increase of heating rate, suggesting that the nucleation and growth rates are carbon-and silicon-diffusion controlled during austenite formation under continuous heating.

关键词： ductile iron austenite continuous heating heating rate kinetics dilatometry

Event-triggered leader-following formation control for multi-agent systems under communication faults: application to a fleet of unmanned aerial vehicles

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1014-1022页

作者： vazquez TREJO Juan Antonio GUENARD Adrien ADAM-MEDINA Manuel PONSART Jean-Christophe CIARLETTA Laurent ROTONDO Damiano THEILLIOL Didier Research Center for Automatic Control of Nancy University of LorraineNancy F-54000France Electronic Engineering Department National Institute of Technology of MexicoCuernavaca Morelos 62490Mexico Lorraine Research Laboratory in Computer Science and Its Applications University of LorraineNancy F-54000France University of Stavanger Department of Electrical and Computer EngineeringStavanger 4021Norway

The main contribution of this paper is the design of an event-triggered formation control for leader-following consensus in second-order multi-agent systems(MASs)under communication *** the agents must follow the trajectories of a virtual leader despite communication faults considered as smooth time-varying delays dependent on the distance between the *** matrix inequalities(LMIs)-based conditions are obtained to synthesize a controller gain that guarantees stability of the synchronization *** on the closed-loop system,an event-triggered mechanism is designed to reduce the control law update and information exchange in order to reduce energy *** proposed approach is implemented in a real platform of a fleet of unmanned aerial vehicles(UAVs)under communication faults.A comparison between a state-of-the-art technique and the proposed technique has been provided,demonstrating the performance improvement brought by the proposed approach.

关键词： event-triggered leader-following consensus communication fault formation control unmanned aerial vehicle(UAV) experimental result

Stepwise magnetization reversal of geometrically tuned in diameter Ni and FeCo bi-segmented nanowire arrays

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Nano Research 2019年第7期12卷 1547-1553页

作者： Ester M. Palmero Miguel Mendez Silvia Gonzalez Cristina Bran Victor Vega Manuel vazquez Victor M. Prida Institute of Materials Science of Madrid (ICMM-CSIC) Madrid 28049Spain Department of Physics University of OviedoFederico Garda Lorca 18Oviedo 33007Spain Division of Permanent Magnets and Applications IMDEA NanoscienceMadrid 28049Spain

Magnetization reversal processes of hexagonal dense arrays of bi-segmented Ni and Fe50Co50 nanowires consisting of two well defined diameters (45 and 80 nm) have been *** nanowires were grown inside of tailored pores of anodic alumina templates by combined anodization,atomic layer deposition (ALD) and electrodeposition *** experiments have allowed to identify their two-step magnetization reversal process ascribed to the respective segments of different *** is concluded from the differential susceptibility observed in the hysteresis loops,contrary to those for nanowires with homogeneous *** results are also confirmed by the first-order reversal curve (FORC) distribution diagrams,where an elongation parallel to the interaction axis around two coercive field values is obtained,which is correlated to the difference in diameter of the two *** well-defined two-step magnetization reversal process through the nanowire diameter design is thought to be very useful for the advanced control of the remagnetization in arrays of magnetic multidomain systems.

关键词： Bi-segmented nanowires nickel iron cobalt alloy stepwise magnetization reversal first-order reversal curve (FORC)

Patency and agile capsules

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World Journal of Gastroenterology 2008年第34期14卷 5269-5273页

作者： ngel Caunedo-lvarez Javier Romero-vazquez Juan M Herrerias-Gutierrez Gastroenterology Service "Virgen Macarena" University Hospital

Small bowel strictures can be missed by current diagnostic methods. The Patency capsule is a new non-endoscopic dissolvable capsule which has as an objective of checking the patency of digestive tract, in a non-invasive manner. The available clinical trials have demonstrated that the Patency capsule is a good tool for assessment of the functional patency of the small bowel, and it allows identification of those patients who can safely undergo a capsule endoscopy, despite clinical and radiographic evidence of small-bowel obstruction. Some cases of intestinal occlusion have been reported with the Patency capsule, four of them needed surgery. So, a new capsule with two timer plugs (Agile capsule) has been recently developed in order to minimize the risk of occlusion. This new device stars its dissolution process earlier (30 h after ingestion) and its two timer plugs have been designed to begin the disintegration even when the device is blocked in a tight stricture.

关键词： Capsule endoscopy Patency capsule Agile capsule Small bowel strictures

Analysis and Validation for an Inverter-side Current Controller in LCL Grid-connected Power Systems

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 387-398页

作者： Jose MSosa Panfilo R.Martinez-Rodriguez Gerardo Escobar Gerardo vazquez Andres A.Valdez-Fernandez Juan F.Martinez-Garcia the Tecnologico Nacional de Mexico/ITS de Irapuato(TecNM/ITESI) IrapuatoGTO 36821Mexico the School of Sciences Autonomous University of San Luis Potosi(UASLP)San Luis PotosiSLP 78290Mexico Tecnologico de Monterrey N.L.64849Mexico

Transformerless grid-connected inverters offer greater efficiencies when transferring power from renewable energy sources to the electrical *** the grid-inverter connection is done with an LCL filter,high attenuation of switching harmonics is achieved while preserving a small-size output ***,damping must be included in the controller to assure closed-loop *** paper proposes a reference computation methodology for the inverter-side current feedback in a photovoltaic(PV)generation system connected to the grid through an LCL *** analysis of the closed-loop system stability and of the steady-state performance are presented as well as experimental validation of the closed-loop *** feedback controller includes active damping and relies on a resonant control structure which improves the ability of dealing with grid harmonic *** controller uses a reduced set of measurements,which requires the inverter-side current and grid voltage only,and assures a power factor close to unity.

关键词： LCL filter transformerless inverter grid connection inverter-side current feedback

Absorption of methionine sources in animals-is there more to know?

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Animal Nutrition 2023年第1期12卷 159-170页

作者： Philippe Becquet Mercedes vazquez-Anon Yves Mercier Dolores I.Batonon-Alavo Frances Yan Karen Wedekind Tahir Mahmood IMAA BrusselsBelgium Novus International Saint CharlesMissouriUSA Adisseo France SAS AntonyFrance

This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of knowledge regarding the absorption mechanism, experimental methodology, and factors affecting their absorption. The 2 Met sources differ in mechanism and site of absorption due to differences in their chemical characteristics and enzymatic conversion. This review addresses diffusion- and transport-mediated absorption systems for amino acids and carboxylic compounds, best elucidated by in vitro, ex vivo, and in vivo experimental models. Opportunities and limitations in the use of radioisotopes to depict absorption sites as well as host and microbial metabolism are described. Physiological and environmental conditions that lead to changes in gut absorptive capacity and the impact of Met source absorption are also evaluated. This review concludes that any comparison between HMTBa and DL-Met should consider their different behaviors during the absorption phase. Hence, the chemical characteristics of these 2 molecules entail different absorption sites and mechanisms, from passive absorption in the case of HMTBa and HMTBa-Ca to active transporters for DL-Met, HMTBa, and HMTBa-Ca. In addition, the different conversion modes of these 2 molecules further differentiate their absorption modes. Considering these important differences, it is easier to understand the apparent divergence between the conclusions of existing publications. When comparing these 2 molecules, it is recommended to properly adapt to the conditions under which the absorption of Met sources is evaluated.

关键词： DL-Methionine Hydroxy-analog of methionine 2-Hydroxy-4-methylthiobutyric acid AbsorptionM ethodology