Testing strong line metallicity diagnostics at z~2

High-z galaxy gas-phase metallicities are usually determined through observations of strong optical emission lines with calibrations tied to the local universe. Recent debate has questioned if these calibrations are valid in the high-z universe. We investigate this by analysing a sample of 16 galaxies at z~2 available in the literature, and for which the metallicity can be robustly determined using oxygen auroral lines. The sample spans a redshift range of 1.4 < z < 3.6, has metallicities of 7.4-8.4 in 12+log(O/H) and stellar masses 10^7.5-10^11 Msun. We test commonly used strong line diagnostics (R23, O3, O2, O32, N2, O3N2 and Ne3O2 ) as prescribed by four different sets of empirical calibrations, as well as one fully theoretical calibration. We find that none of the strong line diagnostics (or calibration set) tested perform consistently better than the others. Amongst the line ratios tested, R23 and O3 deliver the best results, with accuracies as good as 0.01-0.04 dex and dispersions of ~0.2 dex in two of the calibrations tested. Generally, line ratios involving nitrogen predict higher values of metallicity, while results with O32 and Ne3O2 show large dispersions. The theoretical calibration yields an accuracy of 0.06 dex, comparable to the best strong line methods. We conclude that, within the metallicity range tested in this work, the locally calibrated diagnostics can still be reliably applied at z~2.Comment: 12 pages, 8 Figures, accepted for publication in MNRA

From the web of bibliographic data to the web of bibliographic meaning: structuring, interlinking and validating ontologies on the semantic web

Bibliographic data sets have revealed good levels of technical interoperability observing the principles and good practices of linked data. However, they have a low level of quality from the semantic point of view, due to many factors: lack of a common conceptual framework for a diversity of standards often used together, reduced number of links between the ontologies underlying data sets, proliferation of heterogeneous vocabularies, underuse of semantic mechanisms in data structures, "ontology hijacking" (Feeney et al., 2018), point-to-point mappings, as well as limitations of semantic web languages for the requirements of bibliographic data interoperability. After reviewing such issues, a research direction is proposed to overcome the misalignments found by means of a reference model and a superontology, using Shapes Constraint Language (SHACL) to solve current limitations of RDF languages.info:eu-repo/semantics/acceptedVersio

Generalized inverses and their relations with clean decompositions

An element a in a ring R is called clean if it is the sum of an idempotent e and a unit u. Such a clean decomposition a = e + u is said to be strongly clean if eu = ue and special clean if aR eR = (0). In this paper, we prove that a is Drazin invertible if and only if there exists an idempotent e and a unit u such that an = e + u is both a strongly clean decomposition and a special clean decomposition, for some positive integer n. Also, the existence of the Moore-Penrose and group inverses is related to the existence of certain - clean decompositions.This research is supported by the Natural Science Foundation of Anhui Province (No. 1808085QA16), the Fundamental Research Funds for the Central Universities (No. JZ2018HGTB0233), China Postdoctoral Science Foundation (No. 2018M632385) and the Portuguese Funds through FCT- ‘Fundação para a Ciência e a Tecnologia’, within the project UID-MAT-00013/2013

Undulation instabilities in the meniscus of smectic membranes

Using optical microscopy, phase shifting interferometry and atomic force microscopy, we demonstrate the existence of undulated structures in the meniscus of ferroelectric smectic-C* films. The meniscus is characterized by a periodic undulation of the smectic-air interface, which manifests itself in a striped pattern. The instability disappears in the untilted smectic-A phase. The modulation amplitude and wavelength both depend on meniscus thickness. We study the temperature evolution of the structure and propose a simple model that accounts for the observed undulations.Comment: Submitted to PR

State of the art of business models: A bibliometric analysis

Various studies have investigated the business model (BM) in different dimensions. However, bibliometric analyses in this discipline are still limited. This study aims to conduct a bibliometric analysis of business model research, identifying the state of the art, trends, and other indicators by analyzing articles published on the Web of Science (WoS) platform from 2017 to 2022. The present study examines the simultaneous occurrence of publications by year, keyword trends, bibliographic coupling, analysis of co-authorship, cities, and institutions, and finds that the literature on business models rapidly expanded between 2017 and 2020. A total of 14,881 articles were obtained as samples. The present study employs VOSviewer software to analyze the data. A considerable amount of literature has been produced on BMs, but researchers have stopped developing further literature which is thought-provoking. Based on the findings of this study, it is concluded that there is a need to research BMs in different domains such as sustainability and digitalization.info:eu-repo/semantics/publishedVersio

Fratura Proximal do Fémur Bilateral. Incidência e Fatores de Risco de Fratura Contralateral

Nos doentes com fratura osteoporótica da extremidade proximal do fémur, pouco é conhecido sobre a incidência e fatores de risco de fratura contralateral da extremidade proximal do fémur. O objetivo deste trabalho foi, através de um estudo retrospetivo determinar a incidência e os fatores de risco para fratura bilateral da extremidade proximal do fémur não contemporânea. Foram analisados os processos de 1911 doentes com fratura da extremidade proximal do fémur entre 2003 e 2009. Os dados recolhidos sobre as fraturas, tratamentos e comorbilidades foram trabalhados estatisticamente. Um total de 64 doentes (3,24%) teve fratura bilateral da extremidade proximal do fémur, com uma média de idades acima dos 80 anos. Determinou-se que existe uma relação direta entre o tipo da primeira e segunda fratura (intracapsular vs extraapsular), e que 70% das segundas fraturas ocorrem nos primeiros três anos após fratura. Das comorbilidades verificou-se que a doença de Parkinson, Hipertensão Arterial, doença Cardíaca, Anemia e alterações da Visão representam um risco acrescido para fratura contralateral da extremidade proximal do fémur. Propomos um follow-up mais rigoroso nos primeiros três anos após a primeira fratura e estabelecidas melhores formas de prevenção de fraturas e otimização das comorbilidades nos doentes com fatores de risco

Benefits measurement of a plan to reduce hypertension in a healthcare foundation using the BCTool

The hypertension is a well know problem and associated with a high salt consuming is one of the commonest chronic diseases.To measure the impact of this consuming it has been applied the methodology provided by the Business Case tool (BC Tool), in a Portuguese foundation for elderly, in order to contribute for Intervention Plan for the reduction of hypertension which aims to reduce salt consumption in the Portuguese population and to improve the control of Hypertension through a phased reduction in salt consumption.This objective has been achieved by changing the availability of foods with lower salt contents and by decreasing the addition of salt in cooking. The results of these measures provided a substantial benefit in terms of Benefits Measurements and Cost Analysis besides the results of SROI measurement in order to obtain the social benefits of this initiative of the Intervention plan to reduce hypertension. Along these results it has been collected the suggestions for improvements that would allow the Sarah Beirão Foundation's response to the needs of its users to be improved.info:eu-repo/semantics/publishedVersio

Bibliographic ontologies and the semantic web: limitations and research proposals

A literatura sobre dados e ontologias bibliográficos na Web Semântica identifica problemas, não ao nível das instâncias de dados ou da sua publicação em conjuntos isolados, mas sim relativamente às ontologias que descrevem os conceitos que lhe estão subjacentes, com reflexo na qualidade da interoperabilidade semântica e na partilha de ontologias entre sistemas. Aborda-se a adequação à Web Semântica dos modelos conceptuais e limitações de FRBR - Functional Requirements for Bibliographic Records (IFLA 1998, 2018) ; a ausência de enquadramento conceptual comum; a insuficiência de mecanismos semânticos; a baixa e deficiente reutilização de vocabulários externos; e a inadequação das metodologias de mapeamento aplicadas. Apresenta-se um projeto de investigação que propõe uma solução para os problemas semânticos de partilha de ontologias, através da criação de um modelo de referência conceptualmente enquadrador e de uma ontologia de referência que funcione como instrumento de relacionamento semântico de alto nível e de validação de dados, recorrendo à linguagem SHACL - Shapes Constraint Language (KNUBLAUCH e KONTOKOSTAS, 2017).info:eu-repo/semantics/publishedVersio

Global phylogeography and evolution of chelonid fibropapilloma-associated herpesvirus

A global phylogeny for chelonid fibropapilloma-associated herpesvirus (CFPHV), the most likely aetiological agent of fibropapillomatosis (FP) in sea turtles, was inferred, using dated sequences, through Bayesian Markov chain Monte Carlo analysis and used to estimate the virus evolutionary rate independent of the evolution of the host, and to resolve the phylogenetic positions of new haplotypes from Puerto Rico and the Gulf of Guinea. Four phylogeographical groups were identified: eastern Pacific, western Atlantic/eastern Caribbean, mid-west Pacific and Atlantic. The latter comprises the Gulf of Guinea and Puerto Rico, suggesting recent virus gene flow between these two regions. One virus haplotype from Florida remained elusive, representing either an independent lineage sharing a common ancestor with all other identified virus variants or an Atlantic representative of the lineage giving rise to the eastern Pacific group. The virus evolutionary rate ranged from 1.62x10(-4) to 2.22x10(-4) substitutions per site per year, which is much faster than what is expected for a herpesvirus. The mean time for the most recent common ancestor of the modern virus variants was estimated at 192.90-429.71 years ago, which, although more recent than previous estimates, still supports an interpretation that the global FP pandemic is not the result of a recent acquisition of a virulence mutation(s). The phylogeographical pattern obtained seems partially to reflect sea turtle movements, whereas altered environments appear to be implicated in current FP outbreaks and in the modern evolutionary history of CFPHV.DNER-PR; US NMFS (NMFS-NOAA) [NA08NMF4720436]; US-Fish and Wildlife Service (USFWS); Sociedad Chelonia; WIDECAST; US Environmental Protection Agency (US-EPA); Lisbon Oceanarium, Portugal; Interdisciplinary Research Center for Animal Health of the Faculty of Veterinary Medicine of the Technical University of Lisbon (FMV/TUL)info:eu-repo/semantics/publishedVersio