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Atrial fibrillation (AF) is one of the most common cardiac diseases. However, a complete understanding of how to treat patients suffering from AF is still not achieved. As the isolation of the pulmonary veins in the left atrium (LA) is the standard treatment for AF, the role of the right atrium (RA) in AF is rarely considered. We investigated the impact of including the RA on arrhythmia vulnerability in silico. We generated a dataset of five mono-atrial (LA) and five bi-atrial models with three different electrophysiological (EP) setups each, regarding different states of AF-induced remodelling. For every model, a pacing protocol was run to induce reentries from a set of stimulation points. The average share of inducing points across all EP setups was 0.0, 0.8 and 6.7% for the mono-atrial scenario, 0.5, 27.3 and 37.9% for the biatrial scenario. The increase in inducibility of LA stimulation points from mono- to bi-atrial scenario was 0.91 ± 2.03%, 34.55 ± 14.9% and 44.2 ± 14.9 %, respectively. In this study, the RA had a marked impact on the results of the vulnerability assessment that needs to be further investigated.

Atrial fibrillation (AF) is the most common sustained arrhythmia posing a significant burden to patients and leading to an increased risk of stroke and heart failure. Additional ablation of areas of arrhythmogenic substrate in the atrial body detected by either late gadolinium enhancement magnetic resonance imaging (LGE-MRI) or electroanatomical mapping (EAM) may increase the success rate of restoring and maintaining sinus rhythm compared to the standard treatment procedure of pulmonary vein isolation (PVI). To evaluate if LGE-MRI and EAM identify equivalent substrate as potential ablation targets, we divided the left atrium (LA) into six clinically important regions in ten patients. Then, we computed the correlation between both modalities by analyzing the regional extents of identified pathological tissue. In this regional analysis, we observed no correlation between late gadolinium enhancement (LGE) and low voltage areas (LVA), neither in any region nor with regard to the entire atrial surface (-0.3

The repeated, rapid and often pronounced patterns of evolutionary divergence observed in insular plants, or the 'plant island syndrome', include changes in leaf phenotypes, growth, as well as the acquisition of a perennial lifestyle. Here, we sequence and describe the genome of the critically endangered, Galápagos-endemic species Scalesia atractyloides Arnot., obtaining a chromosome-resolved, 3.2-Gbp assembly containing 43,093 candidate gene models. Using a combination of fossil transposable elements, k-mer spectra analyses and orthologue assignment, we identify the two ancestral genomes, and date their divergence and the polyploidization event, concluding that the ancestor of all extant Scalesia species was an allotetraploid. There are a comparable number of genes and transposable elements across the two subgenomes, and while their synteny has been mostly conserved, we find multiple inversions that may have facilitated adaptation. We identify clear signatures of selection across genes associated with vascular development, growth, adaptation to salinity and flowering time, thus finding compelling evidence for a genomic basis of the island syndrome in one of Darwin's giant daisies.

Background: The processes involved in this study were 2-fold. First, we analyzed the levels of resilience and internalized problems (defined as group of emotional symptoms) in children aged 9 to 12 years. Second, we examined whether the relationship between them varies according to the low or high vulnerability of school communities. Methods: About 1460 students from schools in northern Chile participated. A total of 52.6% were girls, and 47.4% were boys. The scales of internalizing problems of the System of Evaluation of Children and Adolescents (SENA) and the short scale of resilience (CYRM-12) were applied. Correlations in each group and differences between groups were analyzed using a MANOVA. A 2-level path analysis was also performed. Results: Resilience was higher in the context of low vulnerability while depression, social anxiety, and posttraumatic stress symptomatology were greater in the context of high vulnerability. A 2-level path analysis showed that the slope of gender, anxiety, and depression symptomatology varies between schools and an interaction effect between vulnerability and anxiety symptomatology. Conclusion: There are differences in the relationship between internalized problems and resilience according to whether the students belong to low or high vulnerability establishments. This study contributes to a better understanding of the relationship between internalizing problems and resilience.

There are a few baseline reef-systems available for understanding the microbiology of healthy coral reefs and their surrounding seawater. Here, we examined the seawater microbial ecology of 25 Northern Caribbean reefs varying in human impact and protection in Cuba and the Florida Keys, USA, by measuring nutrient concentrations, microbial abundances, and respiration rates as well as sequencing bacterial and archaeal amplicons and community functional genes. Overall, seawater microbial composition and biogeochemistry were influenced by reef location and hydrogeography. Seawater from the highly protected crown jewel offshore reefs in Jardines de la Reina, Cuba had low concentrations of nutrients and organic carbon, abundant Prochlorococcus, and high microbial community alpha diversity. Seawater from the less protected system of Los Canarreos, Cuba had elevated microbial community beta-diversity whereas waters from the most impacted nearshore reefs in the Florida Keys contained high organic carbon and nitrogen concentrations and potential microbial functions characteristic of microbialized reefs. Each reef system had distinct microbial signatures and within this context, we propose that the protection and offshore nature of Jardines de la Reina may preserve the oligotrophic paradigm and the metabolic dependence of the community on primary production by picocyanobacteria.

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The present work describes the challenges faced during the development of a countrywide Learning Analytics study and tool focused on tracking and understanding the trajectories of Uruguayan students during their first three years of secondary education. Due to the large scale of the project, which covers an entire national educational system, several challenges and constraints were faced during its conception and development. Examples of key challenges were: to understand the different nuances of the educational system, to satisfy ethical and legal requirements without narrowing down the scope and potential novelty of the initiative and to deal with integration and inconsistencies in the databases. This paper presents the design decisions and solutions found to address or mitigate the problems found as a contribution to facilitate similar large-scale projects. Three main experiments using data mining were conducted and their results are also described, pointing out the feasibility of finding meaningful patterns that can be used by educational authorities to improve their decision making and foster public educational policies. Finally, the paper describes the use of the data and the findings of the study to create an interactive visual tool to explore the relationship between student variables, performance and persistence in the system.