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Attention-driven tile splitting method for improved efficiency of omnidirectional versatile video coding
Publication . Carreira, J.; Faria, Sergio M. M. de; Tavora, Luis M. N.; Navarro, Antonio; Assuncao, Pedro A.
A common approach used in omnidirectional video coding is based on frame splitting into tiles, allowing partial delivery of only the subset of tiles that is necessary to render the user’s current viewing region, defined as a specific viewport or Field-of-View (FoV). Since tiles can be independently encoded, such mechanism provides a flexible solution for encoding planar representations with ultra-high definition (UHD), such as the Equirectangular Projection (ERP), using Versatile Video Coding (VVC). By only selecting and transmitting the coded data that is required to render the necessary FoV, rather than the full 360°, a great deal of bandwidth can be saved. While current solutions are based on splitting the omnidirectional video frames into tiles of equal size, this paper proposes a new approach based on adaptive tile size, driven by visual attention. Those regions where the visual attention is higher are partitioned in smaller tiles to obtain higher bit rate granularity, allowing to decode the most frequent FoVs with minimum out-of-FoV pixels and reduced bandwidth. Optimal tile boundaries are found by solving a lagrangian minimisation problem with a cost function that achieves the best tradeoff between the standard deviation and the average attention-weighted bit rate per tile. The experimental results show that an average of 7.17% and 17.73% of bit rate savings is obtained in comparison with conventional tilling methods for the commonly used FoVs of 90° ×90° and 45° ×45°, respectively.
Movimentos de profissionalização histórica: a relação entre as catástrofes sociais e a enfermagem moderna
Publication . Santos, Paulo Alexandre Figueiredo dos; Rabiais, Isabel Cristina Mascarenhas; Amendoeira, José Joaquim Penedos; Figueiredo, Amélia Simões; Berenguer, Sílvia Maria Alves Caldeira; Pereira, Maria Cristina Queiroz Vaz
Contexto: É em contexto de catástrofes sociais que a afirmação socioprofissional do enfermeiro se constitui uma referência.
Objetivo: Dimensionar a relação entre as catástrofes sociais e a relevância do trabalho realizado por determinadas enfermeiras, no final do século XIX, com contributo para a construção/evolução da enfermagem enquanto profissão.
Metodologia: Embora as opções metodológicas na validação do caráter científico deste estudo histórico assentem na historiografia, os factos narrados e interpretados foram contextualizados em função da época histórica, permitindo o emergir de novos significados que possibilitem definir no próprio tecido documental, unidades, conjuntos, séries, relações inovadoras.
Resultados: Foram várias as enfermeiras que contribuíram para a evolução da enfermagem enquanto ciência. Experienciaram a sua profissão em contextos com um denominador comum: os conflitos armados que se traduziram num cenário de catástrofe social, onde imperava a necessidade de cuidar do Outro.
Conclusão: É inegável que os contextos de catástrofes sociais permitiram um campo de atuação que conferiu visibilidade à enfermagem moderna e possibilitou um caminho, traçado no sentido de construir a enfermagem enquanto disciplina.
The golden mackerel: first report of a xanthic Mediterranean horse mackerel Trachurus mediterraneus (Steindachner, 1868) from Sines, Portugal
Publication . Vasco-Rodrigues, Nuno; Santos, Simão; Espírito-Santo, Cristina; Almada, Frederico
In this study, a single xanthic case of the Mediterranean horse mackerel Trachurus mediterraneus is reported. The individual, with a total lenght (TL) of 306 mm, was captured off Sines (Portugal) in March 2018, by a local fishing boat, using a seine net. This represents the first record of xanthism for this species and for any species of mackerel. The specimen is described here and compared with those of normal pigmentation. Considerations about the paucity of records for this or similar species are presented here, and the possibility of this condition being more frequent than previously thought is discussed.
The Arabic Control Attitudes Scale-Revised: Method Effect (Negatively Worded Items) and Measurement Invariance as Threats to Its Construct Validity Are Remedied in a 5-Item Version With Improved Performance
Publication . Ali, Amira Mohammed; Al-Dossary, Saeed A.; Alharrasi, Maryam; Laranjeira, Carlos; Ayed, Ahmad; El-Gazar, Heba Emad; Zoromba, Mohamed Ali; Atalla, Amal Diab Ghanem; Alamer, Rasmieh; Al-Abri, Khalood; Subih, Maha; Pakai, Annamaria
Background:
The Control Attitudes Scale-Revised (CAS-R) is widely used to explore cardiac patients’ beliefs about their ability to manage illness. The CAS-R’s construct validity may be questionable in different cultural contexts. Conclusions/applications based on inaccurate construct validity can be misleading and incorrect.
Objective:
In this study, we aimed to evaluate the psychometric properties of the Arabic version of the CAS-R.
Methods:
Within a cross-sectional design involving 180 Omani patients with heart failure (mean age = 70.3 ± 9.8 years, 51.7% females), exploratory/confirmatory factor analysis (CFA) and multigroup CFA were used to evaluate the construct validity and measurement invariance of the CAS-R across gender and marital groups.
Results:
In exploratory factor analysis, 2 factors with eigenvalues >1 explained 37.9% of the variance. Despite the poor fit of the unidimensional CAS-R, CFA revealed an excellent fit of a 2-factor structure. Negative (5 and 8) and cross-loading items (1) contributed to scale variance at the configural level. Eliminating negative items and item 6 improved model fit, reliability (Cronbach’s α = 0.66 vs. 0.56), and invariance at all levels. In support of its convergent and criterion validity, the CAS-R 5 correlated with the CAS-R and depression (r = 0.953, −0.268; P values <.01).
Conclusions:
Negative items comprised a minor weak factor (helplessness) that was not stable across groups. Eliminating items 5, 6, and 8 resulted in a clean invariant short form (CAS-R 5) with superior properties that may implicate nursing decisions and interventions concerning perceived control.
Health Literacy of the Polytechnic of Leiria Students
Publication . Ascenso, Rita Margarida Teixeira; Dias, Sara Simões; Luis, Luis; Gonçalves, Dulce
Health Literacy (HL) has several definitions and numerous HL assessment tools. Several systematic reviews on HL identified tools for HL assessment. Health Literacy Survey with 47 questions (HLS-EU-Q47) for Europe was adapted for 16 questions (HLS-EU-Q16), and for only 6 questions (HLS-EU-Q6). These are already in Portuguese and have been used to assess HL since 2017. The studies involved the Portuguese population, and recently, in 2021, the HL evaluation in university students identified limitations in HL. The HLS-EU-Q16_Pt used showed adequate internal consistency (Cronbach's alpha = 0.778, [0.737, 0.816]). Among 251 students from the Polytechnic of Leiria there was a statistically significant association of HL scores with the health area, and more evident when students had a previous degree in health.