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Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： Francisco E Jorge josé R da costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

An illustrated checklist of macrofaunal molluscs from soft-sediments of the Abrolhos Parcel(northeastern,Brazil)with 15 new records

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Journal of Oceanology and Limnology 2021年第2期39卷 671-682页

作者： Flávia Maria pereira da costa Ana Maria Setubal PIRES-VANIN Departamento de Oceanografi a Biológica Instituto Oceanográfi coUniversidade de São PauloSão Paulo 05508-120Brazil

Comprehensive understanding of marine biodiversity is essential for conservation,especially for vulnerable *** this paper,we implemented and illustrated a checklist of molluscs from the Abrolhos Parcel,Brazil,the most important coralline area in South Atlantic *** list features 100 species belonging to 4 classes and 85 genera,of which 15 are new records for Bahia State,northeast *** results highlight the potential for new records in the *** species came from 54 unconsolidated sediment samples collected from the bottom of the reef with a 0.042-m^(2) van Veen *** the listed species,Curveulima sp.,Notarchus *** Guyanella clenchi are new records for the South Atlantic,while Caecum metamorphosicum,Eratoidea janeiroensis,Volvarina serrei,Solemya notialis,Solariorbis shimeri,and Amphithalamus glabrus are endemic to Brazilian waters.A comparison of our results with those obtained in other reef environments indicates that the Abrolhos Parcel has a rich malacofauna and suggests that many more species can still be found with more samplings.

关键词： Bivalvia Gastropoda micromolluscs Scaphopoda Solenogastres southwest Atlantic

Clinical prognostic factors for disabling Crohn's disease: A systematic review and meta-analysis

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World Journal of Gastroenterology 2013年第24期19卷 3866-3871页

作者： Cláudia Camila Dias Pedro pereira Rodrigues Altamiro da costa pereira Fernando Magro Health Information and Decision Sciences Department Faculty of Medicine University of Porto4200-319 Porto Portugal Centre for Research in Health Informatics Systems and Technologies (CINTESIS) 4200-319 Porto Portugal Laboratory of Artificial Intelligence and Decision Support INESC TEC Artificial Intelligence and Decision Support Laboratory4200-465 Porto Portugal Centro Hospital de So Joo Institute of Pharmacology and Therapeutics Faculty of Medicine Univer-sity of Porto4200-319 Porto Portugal Institute for Molecular and Cell Biology (IBMC) 4150-180 Porto Portugal

AIM: To identify demographic and clinical factors asso-ciated with disabling Crohn's disease (CD). METHODS: A systematic review and meta-analysisof observational studies, focusing on the factors that can predict the prognosis of different outcomes of CD was undertaken. PubMed, ISI Web of Knowledge and Scopus were searched to identify studies investigat-ing the above mentioned factors in adult patients with CD. Studies were eligible for inclusion if they describe prognostic factors in CD, with inclusion and exclusion criteria defined as follows. Studies with adult patients and CD, written in English and studying association between clinical factors and at least one prognosis out-come were included. Meta-analysis of effects was un-dertaken for the disabling disease outcome, using odds ratio (OR) to assess the effect of the different factors in the outcome. The statistical method used was Mantel-Haenszel for fixed effects. The 16-item quality assess-ment tool (QATSDD) was used to assess the quality of the studies (range: 0-42). RESULTS: Of the 913 papers initially selected, sixty studies were reviewed and three were included in the systematic review and meta-analysis. The global QA-TSDD scores of papers were 18, 21 and 22. Of a total of 1961 patients enrolled, 1332 (78%) were classified with disabling disease five years after diagnosis. In two studies, age at diagnosis was a factor associated with disabling disease five years after diagnosis. Individu-als under 40 years old had a higher risk of developing disabling disease. In two studies, patients who were treated with corticosteroids on the first flare developed disabling disease five years after diagnosis. Further, perianal disease was found to be relevant in all of the studies at two and five years after diagnosis. Finally, one study showed localization as a factor associated with disabling disease five years after diagnosis, with L3 being a higher risk factor. This meta-analysis showed a significantly higher risk

关键词： Crohn’s disease Disabling disease Prognos-tic factors Outcome Systematic review Meta-analysis

Competition among rare earth elements on sorption onto six seaweeds

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Journal of Rare Earths 2021年第6期39卷 734-741,I0005页

作者： Joāo Pinto Marcelo costa Bruno Henriques joséSoares Mariana Dias Thainara Viana Nicole Ferreira Carlos Vale joséPinheiro-Torres Eduarda pereira Department of Chemistry University of Aveiro3810-193 AveiroPortugal CESAM Department of ChemistryUniversity of Aveiro3810-193 AveiroPortugal LAQV-REQUIMTE Department of Chemistry&Central Laboratory of AnalysisUniversity of Aveiro3810-193 AveiroPortugal CIIMAR一Interdisciplinary Centre of Marine and Environmental Research MatosinhosPortugal N9VE-Nature Ocean and ValueLdaPortoPortugal Central Laboratory of Analysis University of Aveiro3810-193 AveiroPortugal

Sorption has been proposed as a promising approach towards a sustainable water decontamination and recently to the recycling of rare earth elements(REE).Although living seaweed have been shown to be capable of removing REE from contaminated solutions,no studies have yet compared the effects of REE competition on sorption onto different groups of *** effects were analysed in the present study by exposing six living seaweeds(Ulva lactuca,Ulva intestinalis,Fucus spiralis,Fucus vesiculosus,Gracilaria *** Osmundea pinnatifida)(3 g/L,fresh weight) to mono-element and multi-element solutions of Y,La,Ce,Pr,Nd,Eu,Gd,Tb and Dy(1 μmol/L).Results show a preference towards light REE in mono-element solutions,which is reduced when in competition with other *** competitive effect is less pronounced in heavy REE indicating that these are still able to bind to the macroalgae despite the presence of competing *** to water content(%),seaweed specific surface area(cm^(2)/g) shows to be an important factor in the sorption of REE,since larger surface area is associated with higher removal and larger competitive effect.

关键词： Bioaccumulation Wastewater e-waste Recovery Removal Marine macroalgae

Soil texture prediction through stratification of a regional soil spectral library

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Pedosphere 2022年第2期32卷 294-306页

作者： josé Janderson Ferreira costa élvio GIASSON Elisangela Benedet da SILVA Tales TIECHER Antonny Francisco Sampaio DE SENA Ryshardson Geovane pereira de Oliveira E SILVA Department of Soil Science Faculty of AgronomyUniversity of Rio Grande do SulBento Gonçalves Avenue 7712Porto Alegre 91540-000Brazil Agricultural Research and Rural Extension Corporation of Santa Catarina Rodovia Admar Gonzaga 1347FlorianópolisSanta Catarina 88034-901Brazil

Knowing the spatial distribution of soil texture,which is a physical property,is essential to support agricultural and environmental decision *** texture can be estimated using visible,near infrared,and shortwave infrared(Vis-NIR-SWIR)***,the performance of spectroscopic models is variable because of soil ***,few studies address the effects of soil sample variability on the performance of the models,especially for larger spectral libraries that include soils that are more ***,the objectives of this study were to:i)apply Vis-based color parameters on the stratification of a regional soil spectral library;ii)evaluate the performance of the predictive models generated from the spectral library stratification;iii)compare the performance of stratified models(SMs)and the model without stratification(WSM),and iv)explain possible changes in prediction accuracy based on the ***,a regional soil spectral library with 1535 samples from the State of Santa Catarina,Brazil was *** reflectance data were obtained by Vis-NIR-SWIR spectroscopy in the laboratory using a spectroradiometer covering the 350–2500 nm spectral ***,silt,and clay fractions were determined using the pipette ***-two components of color parameters were derived from the Vis spectrum using the colorimetric models.A cubist regression algorithm was used to assess the accuracy of the applicability of the initial models(SMs and WSM)and of the validation between the *** order derivatives(FODs)at 0.5,1.5,and 2 intervals were used to explain possible changes in the performance of the *** SMs with higher contents of clay and iron oxides obtained the highest accuracy,and the most important spectral bands were identified,mainly in the 480–550 and 850–900 nm ranges and the 1400,1900,and 2200 nm ***,stratification of soil spectral libraries is a good strategy to improve regional assessments of soil resou

关键词： color parameters cubist regression fractional order derivatives soil spectroscopy spectroscopic model stratified model Vis-NIR-SWIR

Hole-doping induced ferromagnetism in 2D materials

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npj Computational Materials 2022年第1期8卷 2180-2189页

作者： Ruishen Meng Lino da costa pereira Jean-Pierre Locquet Valeri Afanas’ev Geoffrey Pourtois Michel Houssa Department of Physics and Astronomy KU LeuvenCelestijnenlaan 200DLeuvenB-3001Belgium imec Kapeldreef 75B-3001LeuvenBelgium

Two-dimensional(2D)ferromagnetic materials are considered as promising candidates for the future generations of spintronic ***,2D materials with intrinsic ferromagnetism are ***,high-throughput first-principles simulations are performed to screen 2D materials that present a non-magnetic to a ferromagnetic transition upon hole doping.A global evolutionary search is subsequently performed to identify alternative possible atomic structures of the eligible candidates,and 122 materials exhibiting a hole-doping induced ferromagnetism are *** energetic and dynamic stability,as well as magnetic properties under hole doping are investigated *** of these 2D materials are metal halides,followed by chalcogenides,oxides,and nitrides,some of them having predicted Curie temperatures above 300 *** exchange interactions responsible for the ferromagnetic order are also *** work not only provides theoretical insights into hole-doped 2D ferromagnetic materials,but also enriches the family of 2D magnetic materials for possible spintronic applications.

关键词： ferromagnetic doping materials

Performance of masonry enclosure walls:lessons learned from recent earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第1期11卷 23-34页

作者： Romeu Silva Vicente Hugo Rodrigues Humberto Varum Aníbal costa jos António Raimundo Mendes da Silva University of Aveiro Civil Engineering Department Campus Universitario de SantiagoAveiroPT3810-193Portugal University of Coimbra Civil Engineering Pinhal de MarrocosPolo ⅡCoimbraPT3030Portugal

This paper discusses the issue of performance requirements and construction criteria for masonry enclosure and infill walls. Vertical building enclosures in European countries are very often constituted by non-load-bearing masonry walls, using horizontally perforated clay bricks. These walls are generally supported and confined by a reinforced concrete frame structure of columns and beams/slabs. Since these walls are commonly considered to be nonstructural elements and their influence on the structural response is ignored, their consideration in the design of structures as well as their connection to the adjacent structural elements is frequently negligent or insufficiently detailed. As a consequence, nonstructural elements, as for wall enclosures, are relatively sensitive to drift and acceleration demands when buildings are subjected to seismic actions. Many international standards and technical documents stress the need for design acceptability criteria for nonstructural elements, however they do not specifically indicate how to prevent collapse and severe cracking, and how to enhance the overall stability in the case of moderate to high seismic loading. Furthermore, a review of appropriate measures to improve enclosure wall performance and both in-plane and out-of-plane integrity under seismic actions is addressed.

关键词： RC structures masonry enclosure walls infill walls in-plane out-of-plane cracking performanceimprovement

What exists beyond cag A and vacA? Helicobacter pylori genes in gastric diseases

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World Journal of Gastroenterology 2015年第37期21卷 10563-10572页

作者： Débora Menezes da costa Eliane dos Santos pereira Silvia Helena Barem Rabenhorst Molecular Genetics Laboratory Department of Pathology and Forensic Medicine School of Medicine Federal University of Ceará

Helicobacter pylori(H. pylori) infection is present in more than half the world's population and has been associated with several gastric disorders, such as gastritis, peptic ulceration, and gastric *** clinical outcome of this infection depends on host and bacterial factors where H. pylori virulence genes seem to play a relevant role. Studies of cag A and vac A genes established that they were determining factors in gastric pathogenesis. However, there are gastric cancer cases that are cag A-negative. Several other virulence genes have been searched for, but these genes remain less well known that cag A and vac A. Thus, this review aimed to establish which genes have been suggested as potentially relevant virulence factors for H. pylori-associated gastrointestinal diseases. We focused on the cag-pathogenicity island, genes with adherence and motility functions, and ice A based on the relevance shown in several studies in the literature.

关键词： Helicobacter pylori Virulence genes Cagpathogenici

EFFECTIVE NETWORKS FOR REAL-TIME DISTRIBUTED PROCESSING

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Journal of Systems Science & Complexity 2011年第1期24卷 39-50页

作者： Gonzalo TRAVIESO Luciando da Fontoura costa Instituto de Fisica de Sao Carlos Universidade de Sao Paulo Av. do Trabalhador SSo-Carlensc 400 13566 - 590 Sao Carlos SP Brazil.

This paper applies the concepts and methods of complex networks to the development of models and simulations of master-slave distributed real-time systems by introducing an upper bound in the allowable delivery time of the packets with computation results. Two representative intercom nection models are taken into account： Uniformly random and scale free （Barabasi-Albert）, including the presence of background traffic of packets. The obtained results include the identification of the uniformly random interconnectivity scheme as being largely more efficient than the scale-free counterpart. Also, increased latency tolerance of the application provides no help under congestion.

关键词： Complex networks distributed computing real-time.