32 research outputs found
Implementation of min–max MPC using hinging hyperplanes. Application to a heat exchanger
Min–max model predictive control (MMMPC) is one of the few control techniques able to cope with modelling errors or uncertainties in an explicit manner. The implementation of MMMPC suffers a large computational burden due to the numerical min–max problem that has to be solved at every sampling time. This fact severely limits the range of processes to which this control structure can be applied. An implementation scheme based on hinging hyperplanes that overcome these problems is presented here. Experimental results obtained when applying the controller to the heat exchanger of a pilot plant are given.Ministerio de Ciencia y Tecnología DPI2001-2380-C02-01Ministerio de Ciencia y Tecnología DPI2002-04375-C03-0
La formación del profesorado en las tecnologías de la información y comunicación
[Resumen] La formación en TICs! y más específicamente
en Internet de los docentes es resaltada
en muchos informes y estudios de casos
nacionales e internacionales como el factor
causal por excelencia para entender la mejor
o peor integración de las TICs en las aulas.
El hecho de que los profesores estén
familiarizados a nivel personal con el uso de
las TICs e Internet, no implica automáticamente
que sepan cómo utilizarlos con fines
pedagógicos.
Con nuestra investigación pretendemos
establecer las especificaciones de un proyecto
de red2 informática educativa del
Municipio de A Coruña dentro del programa
"Descubrir la Informática" que se viene
desarrollando cada curso educativo desde
1998. En este caso nos centramos en una de
las secciones analizadas como es la formación
del profesorado[Abstrac] The formation in Tics and more specifically in Internet of the educational ones is emphasized in many information and studies of national and international cases like the causal factor par excellence to understand best or worse integration of the Tics in the classrooms. The fact that the professors are familiarized
at personal level with the use of the TIC
and Internet, does not imply automatically
that they know how to use them with pedagogical aims. With our investigation we try to establish the specifications of a project of educative computer science network of the Municipality of A Corunna within the program "To discover the Computer science" that comes developing each educative course from 1998. In this case we were centered in one of the analyzed sections as it is the lormation
oft he teaching staf
SARS-CoV-2 viral load in nasopharyngeal swabs is not an independent predictor of unfavorable outcome
The aim was to assess the ability of nasopharyngeal SARS-CoV-2 viral load at first patient’s hospital evaluation to predict unfavorable outcomes. We conducted a prospective cohort study including 321 adult patients with confirmed COVID-19 through RT-PCR in nasopharyngeal swabs. Quantitative Synthetic SARS-CoV-2 RNA cycle threshold values were used to calculate the viral load in log10 copies/mL. Disease severity at the end of follow up was categorized into mild, moderate, and severe. Primary endpoint was a composite of intensive care unit (ICU) admission and/or death (n = 85, 26.4%). Univariable and multivariable logistic regression analyses were performed. Nasopharyngeal SARS-CoV-2 viral load over the second quartile (≥ 7.35 log10 copies/mL, p = 0.003) and second tertile (≥ 8.27 log10 copies/mL, p = 0.01) were associated to unfavorable outcome in the unadjusted logistic regression analysis. However, in the final multivariable analysis, viral load was not independently associated with an unfavorable outcome. Five predictors were independently associated with increased odds of ICU admission and/or death: age ≥ 70 years, SpO2, neutrophils > 7.5 × 103/µL, lactate dehydrogenase ≥ 300 U/L, and C-reactive protein ≥ 100 mg/L. In summary, nasopharyngeal SARS-CoV-2 viral load on admission is generally high in patients with COVID-19, regardless of illness severity, but it cannot be used as an independent predictor of unfavorable clinical outcome
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Marine Biodiversity in the Caribbean: Regional Estimates and Distribution Patterns
This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different taxa
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Application of a Self-tuning Regulator to a Solar Power Plant
7th Conference on Digital Computer Applications to Process Control
Viena, AustriaThis paper presents an application of a self-tuning regulator to the distributed collector field of a solar power plant. The distributed collector field consists of a series of parabolic mirrors that reflect solar radiation on a pipe where oil gets heated while circulating. The purpose of the regulator is to maintain the oil outlet temperature as near as possible to a desired level. This is accomplished by varying the flow of the fluid through the field. The field exhibits a variable delay time that depends on the control variable (flow). The transfer function of the process varies with factors such as irradiance level, mirrors reflectance and oil inlet temperature. The self-tuning regulator uses an identifier with a variable forgetting factor and an adaptive PI controller. The paper also describes the heuristic used to make the regulator work an the experiences obtained at the SSPS solar plant of Almeria (Spain)
EDITORIAL BOARD
La Universidad Surcolombiana tiene como misión la formación integral de ciudadanos profesionales a través de la asimilación, producción, aplicación y difusión de conocimientos científicos, humanísticos, tecnológicos, artísticos y culturales, con espíritu crítico para que aborden eficazmente la solución de los problemas del desarrollo humano integral de la región Surcolombiana con proyección nacional e internacional dentro de un marco de libertad de pensamiento, pluralismo ideológico y de conformidad con una ética que consolide la solidaridad y la dignidad humana. ENTORNOS Volumen 26. Núm. 1. Abril de 2013 Las opiniones expresadas en cada uno de los artículos son de exclusiva responsabilidad de los autore