Streaming and User Behaviour in Omnidirectional Videos

Omnidirectional videos (ODVs) have gone beyond the passive paradigm of traditional video, offering higher degrees of immersion and interaction. The revolutionary novelty of this technology is the possibility for users to interact with the surrounding environment, and to feel a sense of engagement and presence in a virtual space. Users are clearly the main driving force of immersive applications and consequentially the services need to be properly tailored to them. In this context, this chapter highlights the importance of the new role of users in ODV streaming applications, and thus the need for understanding their behaviour while navigating within ODVs. A comprehensive overview of the research efforts aimed at advancing ODV streaming systems is also presented. In particular, the state-of-the-art solutions under examination in this chapter are distinguished in terms of system-centric and user-centric streaming approaches: the former approach comes from a quite straightforward extension of well-established solutions for the 2D video pipeline while the latter one takes the benefit of understanding users’ behaviour and enable more personalised ODV streaming

Quality Enhancement of Highly Degraded Music Using Deep Learning-Based Prediction Models for Lost Frequencies

Audio quality degradation can have many causes. For musical applications, this fragmentation may lead to highly unpleasant experiences. Restoration algorithms may be employed to reconstruct missing parts of the audio in a similar way as for image reconstruction-in an approach called audio inpainting. Current state-of-The art methods for audio inpainting cover limited scenarios, with well-defined gap windows and little variety of musical genres. In this work, we propose a Deep-Learning-based (DL-based) method for audio inpainting accompanied by a dataset with random fragmentation conditions that approximate real impairment situations. The dataset was collected using tracks from different music genres to provide a good signal variability. Our best model improved the quality of all musical genres, obtaining an average of 12.9 dB of PSNR, although it worked better for musical genres in which acoustic instruments are predominant

A Cluster-Based Method for Action Segmentation Using Spatio-Temporal and Positional Encoded Embeddings

A crucial task to overall video understanding is the recognition and localisation in time of different actions or events that are present along the scenes. To address this problem, action segmentation must be achieved. Action segmentation consists of temporally segmenting a video by labeling each frame with a specific action. In this work, we propose a novel action segmentation method that requires no prior video analysis and no annotated data. Our method involves extracting spatio-Temporal features from videos in samples of 0.5s using a pre-Trained deep network. Data is then transformed using a positional encoder and finally a clustering algorithm is applied with the use of a silhouette score to find the optimal number of clusters where each cluster presumably corresponds to a different single and distinguishable action. In experiments, we show that our method produces competitive results on Breakfast and Inria Instructional Videos dataset benchmarks

Metagenomic sequencing of clinical samples reveals a single widespread clone of Lawsonia intracellularis responsible for porcine proliferative enteropathy.

Lawsonia intracellularis is a Gram-negative obligate intracellular bacterium that is the aetiological agent of proliferative enteropathy (PE), a common intestinal disease of major economic importance in pigs and other animal species. To date, progress in understanding the biology of L. intracellularis for improved disease control has been hampered by the inability to culture the organism in vitro. In particular, our understanding of the genomic diversity and population structure of clinical L. intercellularis is very limited. Here, we utilized a metagenomic shotgun approach to directly sequence and assemble 21 L. intracellularis genomes from faecal and ileum samples of infected pigs and horses across three continents. Phylogenetic analysis revealed a genetically monomorphic clonal lineage responsible for infections in pigs, with distinct subtypes associated with infections in horses. The genome was highly conserved, with 94 % of genes shared by all isolates and a very small accessory genome made up of only 84 genes across all sequenced strains. In part, the accessory genome was represented by regions with a high density of SNPs, indicative of recombination events importing novel gene alleles. In summary, our analysis provides the first view of the population structure for L. intracellularis, revealing a single major lineage associated with disease of pigs. The limited diversity and broad geographical distribution suggest the recent emergence and clonal expansion of an important livestock pathogen

O ENSINO REMOTO DE EDUCAÇÃO FÍSICA EM NARRATIVA: ENTRE RUPTURAS E APRENDIZADOS NA EXPERIÊNCIA COM A TECNOLOGIA

A literatura tem apostado na compreensão coevolutiva entre tecnologia e educação destacando o professor como peça-chave neste processo. O objetivo do texto é problematizar a vivência pedagógica de uma professora de Educação Física da rede estadual de ensino durante a pandemia de covid-19, sob as lentes do neotecnicismo e das literacias emergentes. Adotou-se a metodologia qualitativa a partir dos estudos narrativos, dos casos pedagógicos e suas contribuições para formação docente. Como resultados percebeu-se o sentimento de incompetência para lidar com plataformas digitais, o apoio de uma rede de colaboração por pares, a urgência do “como utilizar ferramentas tecnológicas” e, em segundo plano, “o que ensinar”. Considera-se, por fim, que pensar o ensino remoto de Educação Física na pandemia é mais do que pensar em tecnologia, mas antes é refletir sobre como o professor se forma pela experiência e as possibilidades de modificação na percepção de aula de Educação Física neste contexto

O ensino remoto de Educação Física em narrativa: entre rupturas e aprendizados na experiência com a tecnologia

Literature has focused on the co-evolutionary understanding between technology and education, highlighting the teacher as a key player in this process. The objective of the text is to problematize the pedagogical experience of a Physical Education teacher from the state education network during the Covid-19 pandemic, under the lens of neotechnicism and emerging literacies. A qualitative methodology was adopted based on narrative studies, pedagogical cases and their contributions to teacher training. As a result, it was noticed the feeling of incompetence to deal with digital platforms, the support of a peer collaboration network, the urgency of “how to use technological tools” and, in the background, “what to teach”. Finally, it is considered that thinking about remote Physical Education teaching in the pandemic is more than thinking about technology, but rather it is reflecting on how the teacher is formed by experience and the possibilities of modifying the perception of Physical Education classes in this context.La literatura se ha centrado en la comprensión coevolutiva entre tecnología y educación, destacando al docente como elemento clave en este proceso. Este texto tiene como objetivo problematizar la experiencia pedagógica de una profesora de Educación Física de la red estatal de educación durante la pandemia de Covid-19, bajo el lente del neotecnicismo y de las literacias emergentes. Se adoptó una metodología cualitativa basada en estudios narrativos, casos pedagógicos y sus aportes a la formación docente. Como resultado, se percibió el sentimiento de incompetencia para trabajar con plataformas digitales, el apoyo a una red de colaboración entre pares, la urgencia de saber “cómo usar las herramientas tecnológicas” y, en segundo plano, “qué enseñar”. Finalmente, se considera que pensar en la enseñanza a distancia de la Educación Física en la pandemia es más que pensar en tecnología, más bien es reflexionar sobre cómo el profesor se forma a partir de la experiencia y las posibilidades de modificar la percepción de las clases de Educación Física en este contexto.A literatura tem apostado na compreensão coevolutiva entre tecnologia e educação destacando o professor como peça-chave neste processo. O objetivo do texto é problematizar a vivência pedagógica de uma professora de Educação Física da rede estadual de ensino durante a pandemia de covid-19, sob as lentes do neotecnicismo e das literacias emergentes. Adotou-se a metodologia qualitativa a partir dos estudos narrativos, dos casos pedagógicos e suas contribuições para formação docente. Como resultados percebeu-se o sentimento de incompetência para lidar com plataformas digitais, o apoio de uma rede de colaboração por pares, a urgência do “como utilizar ferramentas tecnológicas” e, em segundo plano, “o que ensinar”. Considera-se, por fim, que pensar o ensino remoto de Educação Física na pandemia é mais do que pensar em tecnologia, mas antes é refletir sobre como o professor se forma pela experiência e as possibilidades de modificação na percepção de aula de Educação Física neste contexto

The Star Formation History and Dust Content in the Far Outer Disc of M31

We present a detailed analysis of two fields located 26 kpc (~5 scalelengths) from the centre of M31. One field samples the major axis populations--the Outer Disc field--while the other is offset by ~18' and samples the Warp in the stellar disc. The CMDs based on HST/ACS imaging reach old main-sequence turn-offs (~12.5 Gyr). We apply the CMD-fitting technique to the Warp field to reconstruct the star formation history (SFH). We find that after undergoing roughly constant SF until about 4.5 Gyr ago, there was a rapid decline in activity and then a ~1.5 Gyr lull, followed by a strong burst lasting 1.5 Gyr and responsible for 25% of the total stellar mass in this field. This burst appears to be accompanied by a decline in metallicity which could be a signature of the inflow of metal-poor gas. The onset of the burst (~3 Gyr ago) corresponds to the last close passage of M31 and M33 as predicted by detailed N-body modelling, and may have been triggered by this event. We reprocess the deep M33 outer disc field data of Barker et al. (2011) in order to compare consistently-derived SFHs. This reveals a similar duration burst that is exactly coeval with that seen in the M31 Warp field, lending further support to the interaction hypothesis. The complex SFHs and the smoothly-varying age-metallicity relations suggest that the stellar populations observed in the far outer discs of both galaxies have largely formed in situ rather than migrated from smaller galactocentric radii. The strong differential reddening affecting the CMD of the Outer Disc field prevents derivation of the SFH. Instead, we quantify this reddening and find that the fine-scale distribution of dust precisely follows that of the HI gas. This indicates that the outer HI disc of M31 contains a substantial amount of dust and therefore suggests significant metal enrichment in these parts, consistent with inferences from our CMD analysis.Comment: Abstract shortened. 17 pages, 12 figures (+ 6 pages & 5 figures in Appendix). MNRAS, in pres

Oral Kaposi sarcoma development is associated with HIV viral load, CD4+ count and CD4+/CD8+ ratio

Kaposi?s sarcoma (KS) is an uncommon, multifocal and angioproliferative lesion, which demonstrates a poor prognosis. The aim of the present research was to explore the association of HIV viral load, CD4+ and CD8+ counts and the CD4+/CD8+ ratio on the risk of oral Kaposi?s sarcoma (KS) development. A total of 62 patients were retrieved from March 2008 to October 2020 from the files of two oral pathology centres. Clinical, laboratory and follow-up data were retrieved from their medical files. Poisson regression was used to explore the role of history of immunosuppression and its association with oral KS development. A P-value <0.05 was considered significant. Sixty-two patients were included in the present study (32 with oral KS and 30 with no presentation of lesions anywhere on the body). Patients with oral KS presented a mean age of 32.6 years, and male patients were more affected. The hard palate (15 cases; 46.8%) was the main anatomical site affected. The lesions were mostly presented as swellings (13 cases; 40.6%) and nodules (12 cases; 37.5%). Systemic manifestations were also observed, including candidiasis (4 cases; 12.5%), bacterial infection (3 cases; 9.3%), tuberculosis (3 cases; 9.3%), herpes simplex (3 cases; 9.3%) and pneumonia (3 cases; 9.3%). A significant correlation was observed between HIV viral load, CD4+ count and the CD4+/CD8+ ratio with oral KS development. HIV viral load, CD4+ count and the CD4+/CD8+ ratio are associated with oral KS development