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This work proposes an economic model predictive control (EMPC) strategy in the linear parameter varying (LPV) framework for the control of dissolved oxygen concentrations in the aerated reactors of a wastewater treatment plant (WWTP). A reduced model of the complex nonlinear plant is represented in a quasi-linear parameter varying (qLPV) form to reduce computational burden, enabling the real-time operation. To facilitate the formulation of the time-varying parameters which are functions of system states, as well as for feedback control purposes, a moving horizon estimator (MHE) that uses the qLPV WWTP model is proposed. The control strategy is investigated and evaluated based on the ASM1 simulation benchmark for performance assessment. The obtained results applying the EMPC strategy for the control of the aeration system in the WWTP of Girona (Spain) show its effectiveness.

Background: Literature focusing on youth has reported limited evidence and non-conclusive associations between neighborhood walkability measures and active commuting to and from school (ACS). Moreover, there is a lack of studies evaluating both macro- and micro-scale environmental factors of the neighborhood when ACS is analyzed. Likewise, most studies on built environment attributes and ACS focus on urban areas, whereas there is a lack of studies analyzing rural residential locations. Moreover, the relationship between built environment attributes and ACS may differ in children and adolescents. Hence, this study aimed to develop walkability indexes in relation to ACS for urban and rural children and adolescents, including both macro- and micro-scale school-neighborhood factors., Methods: A cross-sectional study of 4593 participants from Spain with a mean age of 12.2 (SD 3.6) years was carried out. Macro-scale environmental factors were evaluated using geographic information system data, and micro-scale factors were measured using observational procedures. Socio-demographic characteristics and ACS were assessed with a questionnaire. Several linear regression models were conducted, including all the possible combinations of six or less built environment factors in order to find the best walkability index., Results: Analyses showed that intersection density, number of four-way intersections, and residential density were positively related to ACS in urban participants, but negatively in rural participants. In rural children, positive streetscape characteristics, number of regulated crossings, traffic calming features, traffic lanes, and parking street buffers were also negatively related to ACS. In urban participants, other different factors were positively related to ACS: number of regulated crossings, positive streetscape characteristics, or crossing quality. Land use mix acted as a positive predictor only in urban adolescents. Distance to the school was a negative predictor on all the walkability indexes. However, aesthetic and social characteristics were not included in any of the indexes., Conclusions: Interventions focusing on improving built environments to increase ACS behavior need to have a better understanding of the walkability components that are specifically relevant to urban or rural samples.

This work studied the accumulation of plastic debris in a remote beach located in La Graciosa island (Chinijo archipelago, Canary Islands). Microplastics were sampled in the 1-5 mm mesh opening range. An average plastic density of 36.3 g/m 2 was obtained with a large variability along the 90 m of the beach (from 8.5 g/m 2 to 103.4 g/m 2 ). Microplastic particles preferentially accumulated in the part of the beach protected by rocks. A total number of 9149 plastic particles were collected, recorded and measured, 87% of which corresponded to fragments. Clear colours and microscopic evidence of weathering corresponded to aged plastics wind-driven by the surface Canary Current. The chemical composition of plastics particles corresponded to PE (63%), PP (32%) and PS (3%). Higher PE/PP ratios were recorded in the more protected parts of the beach, suggesting preferential accumulation of more aged fragments., (Copyright © 2019. Published by Elsevier Ltd.)

Background: Nontuberculous mycobacteria (NTM) are common bacteria in water and especially water supply distribution systems. Some species can cause infections, especially in immunocompromised patients and other risk groups. This study examined the frequency of occurrence of NTM in 135 household potable water samples collected from household water taps in Tenerife Island., Methods: Mycobacteria species were identified by polymerase chain reaction targeting the 16S rRNA and 16S-23S rRNA regions, and by double-reverse hybridization on a dipstick using colloidal gold-bound and membrane-bound probes (Speed-Oligo(®) Mycobacteria). Some species were identified by sequencing the gene that encodes the 16S rRNA region., Results: NTM were present in 47.4% of the samples. Mycobacterium fortuitum was the NTM isolated most frequently (70.3%), followed by Mycobacterium canariasense (6.3%) and Mycobacterium chelonae (6.3%). Other species were isolated at lower percentage frequencies., Conclusion: We isolated and identified the species M. canariasense in water supplies for public consumption. This species has previously been reported only in hospital settings. The elevated presence of NTM in the water supply indicates that it may be a reservoir for infections caused by recently described species of mycobacteria., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Mycobacterium bovis populations in countries with persistent bovine tuberculosis usually show a prevalent spoligotype with a wide geographical distribution. This study applied mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) typing to a random panel of 115 M. bovis isolates that are representative of the most frequent spoligotype in the Iberian Peninsula, SB0121. VNTR typing targeted nine loci: ETR-A (alias VNTR2165), ETR-B (VNTR2461), ETR-D (MIRU4, VNTR580), ETR-E (MIRU31, VNTR3192), MIRU26 (VNTR2996), QUB11a (VNTR2163a), QUB11b (VNTR2163b), QUB26 (VNTR4052), and QUB3232 (VNTR3232). We found a high degree of diversity among the studied isolates (discriminatory index [D] = 0.9856), which were split into 65 different MIRU-VNTR types. An alternative short-format MIRU-VNTR typing targeting only the four loci with the highest variability values was found to offer an equivalent discriminatory index. Minimum spanning trees using the MIRU-VNTR data showed the hypothetical evolution of an apparent clonal group. MIRU-VNTR analysis was also applied to the isolates of 176 animals from 15 farms infected by M. bovis SB0121; in 10 farms, the analysis revealed the coexistence of two to five different MIRU types differing in one to six loci, which highlights the frequency of undetected heterogeneity.

Background: Bovine tuberculosis (bTB) is a chronic infectious disease mainly caused by Mycobacterium bovis. Although eradication is a priority for the European authorities, bTB remains active or even increasing in many countries, causing significant economic losses. The integral consideration of epidemiological factors is crucial to more cost-effectively allocate control measures. The aim of this study was to identify the nature and extent of the association between TB distribution and a list of potential risk factors regarding cattle, wild ungulates and environmental aspects in Ciudad Real, a Spanish province with one of the highest TB herd prevalences., Results: We used a Bayesian mixed effects multivariable logistic regression model to predict TB occurrence in either domestic or wild mammals per municipality in 2007 by using information from the previous year. The municipal TB distribution and endemicity was clustered in the western part of the region and clearly overlapped with the explanatory variables identified in the final model: (1) incident cattle farms, (2) number of years of veterinary inspection of big game hunting events, (3) prevalence in wild boar, (4) number of sampled cattle, (5) persistent bTB-infected cattle farms, (6) prevalence in red deer, (7) proportion of beef farms, and (8) farms devoted to bullfighting cattle., Conclusions: The combination of these eight variables in the final model highlights the importance of the persistence of the infection in the hosts, surveillance efforts and some cattle management choices in the circulation of M. bovis in the region. The spatial distribution of these variables, together with particular Mediterranean features that favour the wildlife-livestock interface may explain the M. bovis persistence in this region. Sanitary authorities should allocate efforts towards specific areas and epidemiological situations where the wildlife-livestock interface seems to critically hamper the definitive bTB eradication success.

Background: Eradication of bovine tuberculosis (bTB) through the application of test-and-cull programs is a declared goal of developed countries in which the disease is still endemic. Here, longitudinal data from more than 1,700 cattle herds tested during a 12 year-period in the eradication program in the region of Madrid, Spain, were analyzed to quantify the within-herd transmission coefficient (β) depending on the herd-type (beef/dairy/bullfighting). In addition, the probability to recover the officially bTB free (OTF) status in infected herds depending on the type of herd and the diagnostic strategy implemented was assessed using Cox proportional hazard models., Results: Overall, dairy herds showed higher β (median 4.7) than beef or bullfighting herds (2.3 and 2.2 respectively). Introduction of interferon-gamma (IFN-γ) as an ancillary test produced an apparent increase in the β coefficient regardless of production type, likely due to an increase in diagnostic sensitivity. Time to recover OTF status was also significantly lower in dairy herds, and length of bTB episodes was significantly reduced when the IFN-γ was implemented to manage the outbreak., Conclusions: Our results suggest that bTB spreads more rapidly in dairy herds compared to other herd types, a likely cause being management and demographic-related factors. However, outbreaks in dairy herds can be controlled more rapidly than in typically extensive herd types. Finally, IFN-γ proved its usefulness to rapidly eradicate bTB at a herd-level.

Spoligotyping and mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) analysis are the international standard techniques for molecular typing of members of the Mycobacterium tuberculosis complex. To enable the exploitation of molecular typing data for epidemiological purposes, the creation of large databases is indispensable. Here we describe mycoDB.es, a database for animal tuberculosis which forms part of the Spanish national programme for eradication of bovine tuberculosis. This database has been created as an epidemiological tool at national level and contains spoligotype patterns of 17,273 isolates clustered in 401 different spoligotypes of Mycobacterium bovis, Mycobacterium caprae and M. tuberculosis. The database offers an overview of the present spoligotypes, to a lower extent also of MIRU-VNTR types, affected animal species and furthermore of the spatial distribution of these genotypes., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Mycobacterium bovis isolates from the Iberian Peninsula are dominated by strains with spoligotype patterns deleted for spacer 21. Whole-genome sequencing of three Spanish strains with spacer 21 missing in their spoligotype pattern revealed a series of SNPs and subsequent screening of a selection of these SNPs identified one in gene guaA that is specific to these strains. This group of strains from the Iberian Peninsula missing spoligotype spacer 21 represents a new clonal complex of M. bovis, defined by the SNP profile with a distinct spoligotype signature. We have named this clonal complex European 2 (Eu2) and found that it was present at low frequency in both France and Italy and absent from the British Isles., (Copyright © 2011 Elsevier B.V. All rights reserved.)

This study describes the attempt to trace the first Mycobacterium bovis outbreak in alpacas (Lama pacos) in Spain by spoligotyping and variable-number tandem-repeat (VNTR) analysis. Due to high genotype diversity, no matching source was identified, but local expansion of a clonal group was found and its significance for molecular tracing is discussed.

Introduction: In July, 2005 the first vancomycin-resistant Enterococcus faecium (VREF) with a genotype vanA was isolated in Hospital Universitario de Canarias (HUC). From September to December 2005, VREF vanA was isolated from another 15 patients (3 nosocomial infections and 12 rectal carriers). All of them were kidney transplant patients hospitalized in the Nephrology ward. This study describes the first VREF vanA outbreak in the HUC and the epidemiological link of the first VREF vanA isolates found in another two university hospitals in the Canary Islands., Materials and Methods: We studied a total of 22 VREF isolates by microbiological and molecular methods. Epidemiological and clinical data of the patients involved were collected., Results and Conclusions: We confirmed that these VREF isolates belonged to the same clone using pulse-field gel electrophoresis (PFGE). In November 2005 and February 2006, the first VREF were isolated in two other University Hospitals in the Canary Islands and we also confirmed the link with the HUC cluster by comparison of patient-related information with the molecular typing data. These VREF isolates belonged to the ST18 associated to the Clonal Complex-17 (CC17). CC17 is the major hospital adapted lineage, representing a polyclonal population and associated to VREF outbreaks and infections in the five continents., (Copyright 2009 Elsevier España, S.L. All rights reserved.)

Background: In Chile, in approximately 50% of nursing students, nursing was not their first choice as career. Usually, during the first year, these students must decide whether they would like to continue in the same career. A valid tool is needed to identify decisional conflicts and their contributing factors among these students and to develop an appropriate strategy to support them during their decision-making process., Aim: To translate into Spanish and validate the Generic Decisional Conflict Scale (DCS)., Material and Methods: The DCS was translated from English to Spanish and was used with 331 first-year nursing students at the Pontificia Universidad Católica de Chile. The scale was assessed for validity and reliability using statistical tests, including factor analysis and Cronbach alpha test., Results: The Spanish version of the DCS had acceptable validity and reliability. Factorial analysis identified four factors and only the item: "advice" loaded the other factors. Cronbach alpha was 0.80., Conclusions: DCS is a valid and useful instrument to identify decisional conflicts and contributing factors to continue studies among nursing students.

This work provides evidence of the significant contribution of recombination to the genetic diversification of emerging begomovirus populations. In southern Spain, Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV) are distinct geminivirus species that coexist in the field and contribute to the tomato yellow leaf curl disease epidemic. A natural recombinant between TYLCSV and TYLCV has been detected and an infectious clone of a recombinant isolate (ES421/99) was obtained and characterized. Analysis of its genome showed that the recombination sites are located in the intergenic region in which a conserved stem-loop structure occurs and at the 3'-end of the replication enhancer protein open reading frame. ES421/99 exhibited a novel pathogenic phenotype that might provide it with a selective advantage over the parental genotypes. This agrees with results from field studies which revealed that the recombinant strain is becoming prevalent in the region in which it was detected.