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C_c(X)Spaces with X Locally Compact

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Acta Mathematica Sinica,English Series 2007年第9期23卷 1593-1600页

作者： J.C.FERRANDO S.MOLL Centro de Investigación Operativa Universidad Miquel Hernández Departamento de Matemática Aplicada Universidad Politécnica

In this paper, we show, among other results, that if X is a [separable] locally compact space X [satisfying the first countability axiom] then the space Cc （X） has countable tightness [if and only if it has bounding tightness] if and only if it is Frechet-Urysohn, if and only if Cc （X） contains a dense （LM） subspace and if and only if X is a-compact.

关键词： Frechet-Urysohn space countable [bounding] tightness (LM)-space

Evaluation of different machine learning methods for land cover mapping of a Mediterranean area using multi-seasonal Landsat images and Digital Terrain Models

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International Journal of Digital Earth 2014年第6期7卷 492-509页

作者： Victor F.Rodriguez-Galiano Mario Chica-Rivas Departamento de Geodinamica Universidad de GranadaGranadaSpain Departamento de Analisis Matematico Universidad de GranadaGranadaSpain

Land cover monitoring using digital Earth data requires robust classification methods that allow the accurate mapping of complex land cover *** paper discusses the crucial issues related to the application of different up-to-date machine learning classifiers:classification trees(CT),artificial neural networks(ANN),support vector machines(SVM)and random forest(RF).The analysis of the statistical significance of the differences between the performance of these algorithms,as well as sensitivity to data set size reduction and noise were also ***-5 Thematic Mapper data captured in European spring and summer were used with auxiliary variables derived from a digital terrain model to classify 14 different land cover categories in south ***,statistically similar accuracies of over 91%were obtained for ANN,SVM and ***,the findings of this study show differences in the accuracy of the classifiers,being RF the most accurate classifier with a very simple ***,followed by RF,was the most robust classifier to noise and data *** differences in their performances were only reached for thresholds of noise and data reduction greater than 20%(noise,SVM)and 25%(noise,RF),and 80%(reduction,SVM)and 50%(reduction,RF),respectively.

关键词： land cover remote sensing classification trees random forest neural networks support vector machines

Frailty and acute coronary syndrome: does gender matter?

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Journal of Geriatric Cardiology 2019年第2期16卷 138-144页

作者： Lourdes Vicent Manuel Martinez-Selles Servicio de Cardiologia Hospital General Universitario Gregorio MaraiionCIBERCVMadridSpain universidad Europea Universidad ComplutenseMadridSpain

There are important sex-related differences in elderly patients with acute coronary syndrome(ACS).Women are older,more frequently frail,and present more comorbidities than *** symptoms at presentation are also more common in female patients,they are leaded to a delayed diagnosis and *** angiography and subsequent revascularization are frequently underused in elderly women and they tend to receive less guidelines-recommended *** prognosis in elderly frail women with ACS is poor,and it is with high mortality and readmissions *** is recurrent ischemic events in which it is more frequent in women than in *** time might be long,and a multidisciplinary approach is desirable to improve prognosis and quality of *** studies are needed in order to clarify the benefit of the different therapies in the group of frail women,and this is particularly true for revascularization,as scientific evidence in this group is very scarce.

关键词： Acute coronary syndrome Frailty The elderly Women

Development of a microcomposite with single-walled carbon nanotubes and Nd_2O_3 for determination of paracetamol in pharmaceutical dosage by adsorptive voltammetry

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Journal of Pharmaceutical Analysis 2019年第1期9卷 62-69页

作者： Verónica Arancibia Johisner Penagos-Llanos Edgar Nagles Olimpo García-Beltrán John J.Hurtado Pontificia universidad Católica de Chile Facultad de Química Facultad de Ciencias Naturales y Matemáticas Universidad de Ibagué Departamento de Química Universidad de los Andes

This study presents for the first time a new composite of carbon paste(CP), single-walled carbon nanotubes(SWCNTs) and Nd2 O3(NdOX). This versatile composite(NdOX-SWCNT/CPE) was applied to the oxidation of paracetamol(PCM). The newly formed surface was characterized by scanning electron microscopy(SEM), electrochemical impedance spectroscopy(EIS) and cyclic voltammetry(CV). The results showed greater conductivity and a higher surface area for the composite than those of the carbon paste alone. Moreover, the anodic peak currents for PCM increased from 1.6 to 3.6 m A with CPE and NdOXSWCNT/CPE, indicating an increase of nearly 51.0% for the anodic peak current. On the other hand, the anodic peak potentials shifted from 0.67 to 0.57 V. The detection limits were 0.05 mmol/L with NdOXSWCNT/CPE and 0.50 mmol/L with SWCNT/CPE. The relative standard deviations(RSDs) were 1.5%(n=7). The accuracy and interference of the methods were evaluated with a urine chemistry control spiked with known quantities of PCM, uric acid, dopamine, ascorbic acid, caffeine, acetylsalicylic acid,tartrazine, sunset yellow, allure red, rutin, morin and metal ions. Finally, the novelty and usefulness of the composite were evaluated to quantify PCM in pharmaceutical dosage forms such as tablets, powders and syrups for children.

关键词： Paracetamol Neodymium(Ⅲ) Oxide Single-walled carbon nanotubes Pharmaceutical dosage

Towards Fully Secure 5G Ultra-Low Latency Communications: A Cost-Security Functions Analysis

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Computers, Materials & Continua 2023年第1期74卷 855-880页

作者： Borja Bordel Ramón Alcarria Joaquin Chung Rajkumar Kettimuthu Tomás Robles Iván Armuelles universidad Politecnica de Madrid MadridEspana Argonne National Laboratory LemontILUSA universidad de Panama PanamaPanama

Future components to enhance the basic,native security of 5G networks are either complex mechanisms whose impact in the requiring 5G communications are not considered,or lightweight solutions adapted to ultrareliable low-latency communications(URLLC)but whose security properties remain under *** different 5G network slices may have different requirements,in general,both visions seem to fall short at provisioning secure URLLC in the *** this work we address this challenge,by introducing cost-security functions as a method to evaluate the performance and adequacy of most developed and employed non-native enhanced security mechanisms in 5G *** categorize those new security components into different groups according to their purpose and deployment *** propose to analyze them in the context of existing 5G architectures using two different ***,using model checking techniques,we will evaluate the probability of an attacker to be successful against each security ***,using analytical models,we will analyze the impact of these security mechanisms in terms of delay,throughput consumption,and ***,we will combine both approaches using stochastic cost-security functions and the PRISM model checker to create a global *** results are first evidence of how a 5G network that covers and strengthened all security areas through enhanced,dedicated non-native mechanisms could only guarantee secure URLLC with a probability of∼55%.

关键词： 5G networks security analysis secure low latency communications URLLC eMBBC

Synthesis of activated carbons from black sapote seeds,characterization and application in the elimination of heavy metals and textile dyes

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Chinese Journal of Chemical Engineering 2020年第2期28卷 613-623页

作者： Alejandra Alicia Peláez-Cid Vincent Romero-Hernández Ana María Herrera-González Alejandro Bautista-Hernández Oscar Coreno-Alonso Facultad de Ingeniería Benemérita Universidad Autónoma de PueblaMexico Instituto de Ciencias Básicas e Ingeniería Universidad Autónoma del Estado de HidalgoMexico División de Ingenierías Universidad de GuanajuatoMexico

Many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue(black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir’s equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using FTIR, EA, SEM, Nitrogen adsorption(specific surface areas of 879 and 652 m2·g-1), and their points of zero charge(2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed(58–59.8 mg·g-1) in greater amounts compared to anionic dyes(10–58.8 mg·g-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system.

关键词： Activated carbons Black sapote seeds Heavy metal adsorption Textile dye adsorption Wastewater treatment

Attitude toward preventive counseling and healthy practices among medical students at a Colombian university

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Frontiers of Medicine 2015年第2期9卷 251-259页

作者： Luz Helena Alba Nora Badoui Fabian Gil Department of Preventive and Social Medicine Pontificia Universidad Javeriana Bogota Colombia Department of Clinical Epidemiology and Biostatistics Pontificia Universidad Javeriana Bogota Colombia

Unhealthy behaviors of medical students influence their attitudes toward preventive counseling. The burden of chronic diseases is continually growing in developing countries, emphasizing the need for the increased role of general practitioners in preventive counseling. The objective of this study was to describe the effect of medical training on the risk profiles and attitudes of medical students toward preventive counseling in a Colombian university. Students in their first and fifth years of training were surveyed using the ＂Healthy Doctor = Healthy Patient＂ questionnaire to assess counseling attitudes; personal practices, such as risky drinking, smoking, inadequate nutrition, and non-compliance with physical activity recommendations; and the university environment. The association among these components was estimated, as well as the effect of the university environment. Risky drinking and smoking decreased from first to fifth year （59.3% vs. 37.1%, P = 0.021 and 31.5~ vs. 25.9%, P = 0.51, respectively）, whereas inadequate nutrition and non-compliance with physical activity recommendations increased. Physical activity （PA） was associated with positive counseling attitude （ORs： nutrition 7.6; alcohol 5.2; PA 10.6）. Areas governed by institutional policies that are emphasized in the curriculum positively affected student practices. PA promoted preventive counseling and healthy lifestyles most effectively. Universities should therefore strengthen their preventive medicine curricula and modify social determinants.

关键词： lifestyle medical students preventive medicine counseling universities schools medical

Temporal decay of the catalytic oxidation of methane over palladium supported on silica

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Science China Chemistry 2013年第11期56卷 1601-1607页

作者： CORTS Joaquín VALENCIA Eliana PINEDA Marcelo ARAYA Paulo Departamento de Ingeniería Química y Biotecnología Universidad de Chile Departamento de Ciencia de Materiales Universidad de Chile

The temporal decay of the oxidation of methane(CH4-O2reaction)over palladium supported on silica is determined experimentally at different temperatures,comparing the results with those of various classical models which show the behavior of the adsorbed phase as the cause of the *** effect is visualized through Monte Carlo simulations of the CH4-O2reaction on a mixed lattice whose partial poisoning,due to the configuration of the OH groups on the surface of the adsorbate,is translated into a gradual decay of the reaction’s activity.

关键词： catalytic CH4-O2 reaction surface heterogeneity in superficial reaction Monte Carlo simulation superficial catalyticreaction CH4-O2 reaction over palladium

THE BANACH-LIE GROUP OF LIE TRIPLE AUTOMORPHISMS OF AN H^＊-ALGEBRA^＊

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Acta Mathematica Scientia 2010年第4期30卷 1219-1226页

作者： A.J.Calderón Martín C.Martín González Departamento de Matemáticas Universidad de Cádiz Departamento de Algebra Geometría y Topología Universidad de Málaga

We study the Banach-Lie group Ltaut（A） of Lie triple automorphisms of a complex associative H^＊-algebra A. Some consequences about its Lie algebra, the algebra of Lie triple derivations of A, Ltder（A）, are obtained. For a topologically simple A, in the infinite-dimensional case we have Ltaut（A）0 = Aut（A） implying Ltder（A） = Der（A）. In the finite-dimensional case Ltaut（A）0 is a direct product of Aut（A） and a certain subgroup of Lie derivations δ from A to its center, annihilating commutators.

关键词： Banach-Lie group Lie triple automorphism Lie triple derivation