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Robots are becoming more of a part of our daily lives. They have become an extension of some our human capabilities and there is a need to develop control algorithms that contribute to the successful deployment of these machines to navigate, explore and map indoor human environments. These robots and their actions, despite our effort to make them as predictable as possible, show stochastic behaviors, as well as motion and sensing uncertainties. We leverage the use of Constrained Markov Decision Processes (CMDP) to balance multi-cost problems with constraints, under the premise of having multiple possible sources of uncertainties. This dissertation engages in solving some of these problems in the following chapters.Initially, we highlight some of the theoretical background about Markov Decision Process (MDP) and its extension the CMDP. From this point we deal with the problem of multiple robots visiting multiple targets, while we fix temporal and failure probability constraints. We present our solution to expand the state space following a binary sequence that represents successful observations of each of the targets. All this is classified as the rapid deployment problem, which we define and solve for a team of robots.Closing the gap between reality and theory, we implement a stochastic model that recreates the motion primitives from a robot. We proceed to use these modeled primitives to create modeled trajectories and extract transition probabilities from them. These transition probabilities characterize some of the robot’s behavior and we use them with our formulation of a CMDP. Then we calculate a navigation policy to traverse some real scenarios.We create and implement a new spatial model dubbed Oriented Topological Semantic Map (OTSM). This new type of map can be built in run-time, and together with a CMDP, we assign actionable temporal deadlines to the robot executing an exploration task. We open-sourced a ROS framework that can be downloaded and used to reproduce our results and we published the first Reproducible Article or R-article in robotics. Consequently, we implement an OTSM by grouping an Orientation System (OS), an Intersection Detection System (IDS), and a Labeling System (LS), using odometry, accelerometers, a LIDAR, and a residual neural network resNet, to extract the orientation, the topology, and the semantics of an indoor environment.In the last part of this dissertation we propose a new algorithm to merge together pieces of OTSMs when a group of robots have the task to explore an unknown environment. Then they combine their local maps into a global map. Our solution was inspired from research in cognitive science that focused on object recognition. Applying this theory, we create a two-stage method to compare vertices in different OTSMs and measure their resemblance.

Background Advanced age is a well-known risk factor for poor prognosis in COVID-19. However, few studies have specifically focused on very old inpatients with COVID-19. This study aims to describe the clinical characteristics of very old inpatients with COVID-19 and identify risk factors for in-hospital mortality at admission. Methods We conducted a nationwide, multicenter, retrospective, observational study in patients ≥ 80 years hospitalized with COVID-19 in 150 Spanish hospitals (SEMI-COVID-19) Registry (March 1–May 29, 2020). The primary outcome was in-hospital mortality. A uni- and multivariate logistic regression was performed to assess predictors of mortality at admission. Results A total of 2772 consecutive patients (49.4% men, median age 86.3 years) were analyzed. Rates of atherosclerotic cardiovascular disease, diabetes mellitus, dementia, and Barthel Index < 60 were 30.8%, 25.6%, 30.5%, and 21.0%, respectively. The overall case-fatality rate was 46.9% (n: 1301) and increased with age (80–84 years: 41.6%; 85–90 years: 47.3%; 90–94 years: 52.7%; ≥95 years: 54.2%). After analysis, male sex and moderate-to-severe dependence were independently associated with in-hospital mortality; comorbidities were not predictive. At admission, independent risk factors for death were: oxygen saturation < 90%; temperature ≥ 37.8°C; quick sequential organ failure assessment (qSOFA) score ≥ 2; and unilateral–bilateral infiltrates on chest x-rays. Some analytical findings were independent risk factors for death, including estimated glomerular filtration rate < 45 mL/min/1.73 m2; lactate dehydrogenase ≥ 500 U/L; C-reactive protein ≥ 80 mg/L; neutrophils ≥ 7.5 × 103/μL; lymphocytes < 0.8 × 103/μL; and monocytes < 0.5 × 103/μL. Conclusions This first large, multicenter cohort of very old inpatients with COVID-19 shows that age, male sex, and poor preadmission functional status—not comorbidities—are independently associated with in-hospital mortality. Severe COVID-19 at admission is related to poor prognosis.

Additional file 1. List of the SEMI-COVID-19 Network members.

Additional file 1: Supplementary Figure 1. Hospitalization annual trends in people > 85 years old in Spain per 100 global discharges by age group, from 2000 to 2015. Supplementary Figure 2. Annual trends in people > 85 years of the proportion of deaths per age group, from 2000 to 2015. Supplementary Figure 3. Annual trends in people > 85 years of mean length of stay per age group, from 2000 to 2015

Background: Neurocysticercosis (NCC) is the most common parasitic neurological disease worldwide and a major cause of epilepsy. Spain is the country reporting the highest number of NCC imported cases in Europe. Methodology: Retrospective case series of NCC patients registered in the +REDIVI Network from October 1, 2009 to July 2018. A specific questionnaire, including clinical and diagnostic characteristics, was created and sent to the collaborator centers. Results: 46 cases were included in the analysis. 55% were male, mean age of 40 years. 95.6% were migrants. The median duration since migration from an endemic area was 10 years. Predominant nationalities were Ecuadorians (50%) and Bolivians (30.4%). Frequent locations were parenchymal (87%), subarachnoid (26.1%) and intraventricular cysts (10.9%). Serological analysis was performed in 91.3%, being 54.8% positive. Most prevalent clinical manifestations were persistent headache (60.9%), epilepsy (43.5%) and visual changes (13%). Patients were mainly treated with albendazole (76.1%), corticosteroids (67.4%), and anticonvulsionants (52.2%). 82.5% had a favorable clinical outcome. Conclusions: Most NCC cases were long-standing migrants. Few clinical differences were observed depending on the cysticerci location. The treatment was often not according to current recommendations, and no uniform criteria were followed when it came to the therapeutic regimen. NCC case management in Spain (including clinician awareness and laboratory capacity improvements) needs to be strengthened., We would thanks Maria Jesus Perteguer from the National Center of Microbiology for the information and update on NCC lab techniques currently performed in Spain. The corresponding author's affiliation centre belongs to the ISCIII-Sub. Gral. Redes-Network Biomedical Research on Tropical Diseases (RICET in Spanish) grant RD16CIII/0003/0001, RD16/0027/0020, RD16CIII/0003/0001 and the European Regional Development Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.