Star fows and multisingular hyperbolicity

A vector field X is called a star flow if every periodic orbit, of any vector field C1-close to X, is hyperbolic. It is known that the chain recurrence classes of a generic star flow X on a 3 or 4 manifold are either hyperbolic or singular hyperbolic (see [MPP] for 3-manifolds and [GLW] on 4-manifolds). As it is defined, the notion of singular hyperbolicity forces the singularities in the same class to have the same index. However, in higher dimension (i.e $\geq 5$) \cite{BdL} shows that singularities of different indices may be robustly in the same chain recurrence class of a star flow. Therefore the usual notion of singular hyperbolicity is not enough for characterizing the star flows. We present a form of hyperbolicity (called multi-singular hyperbolic) which makes compatible the hyperbolic structure of regular orbits together with the one of singularities even if they have different indices. We show that multisingular hyperbolicity implies that the flow is star, and conversely, there is a C1-open and dense subset of the an open set of star flows which are multisingular hyperbolic. More generally, for most of the hyperbolic structures (dominated splitting, partial hyperbolicity etc...) well defined on regular orbits, we propose a way for generalizing it to a compact set containing singular points.Comment: There are new results in section 7 compared with the previous versio

Data science for infection management & antimicrobial stewardship

Improving infection management and supporting the rational use of antimicrobials through antimicrobial stewardship requires different disciplines to interact in shared clinical decision-making processes. This thesis explores the use of data science to support these processes by leveraging data from routine electronic health records. New approaches to data wrangling, data visualization, and data modelling and prediction were developed and tested for their potential to support clinicians with data insights that can ultimately improve the quality of patient care

First report of Metarhizium anisopliae IP 46 pathogenicity in adult Anopheles gambiae s.s. and An. arabiensis (Diptera; Culicidae).

The entomopathogenic fungus Metarhizium anisopliae isolate IP 46, originating from a soil sample collected in 2001 in the Cerrado of Central Brazil, was tested for its ability to reduce the survival of adult male and female Anopheles gambiae s.s. and An. arabiensis mosquitoes. A 6-h exposure to the fungus coated on test paper at a concentration of 3.3 x 106 conidia cm-2 reduced the daily survival of both mosquito species (HR = 3.14, p < 0.001), with higher risk of dying in An. gambiae s.s relative to An. arabiensis (HR = 1.38, p < 0.001). Fungal sporulation was observed in >95% of mosquito cadavers in the treatment groups. The results indicate that M. anisopliae IP 46 has the potential to be a bio-control agent for African malaria vector species, and is a suitable candidate for further research and development

Dos aproximaciones a la metodología de diseño a momento flexionante de secciones T en concreto reforzado que se comportan como rectangulares y constituyen la sección recta de la viguetería de losas aligeradas

El presente artículo esboza dos aproximaciones sobre la ecuación de diseño a momento flexionante de secciones T en concreto reforzado que se comportan como secciones rectangulares y que trabajan como viguetería de losas aligeradas. La primera aproximación discute la viabilidad de usar el ancho del nervio de la vigueta en lugar de usar el ancho efectivo de la aleta, dentro del proceso de la obtención del acero, requerida para asumir un momento flexionante; la segunda aproximación discute la viabilidad de aproximar la ecuación cuadrática que rige la obtención del área del acero requerida para obtener un momento flexionante en una ecuación lineal, cuyas únicas variables son el área del acero y la altura efectiva de la sección T. Se ha dimensionado geométricamente un conjunto de secciones de losas aligeradas siguiendo los requisitos del título C13 de la norma sismo resistente colombiana NSR98, los cuales se obtuvieron para un modelo simplemente apoyado, cuya luz varía entre [2 - 7] m y el ancho del casetón ente [0.30 – 1] m. El dimensionamiento antes mencionado fue utilizado para sensibilizar la efectividad de cada una de las aproximaciones propuestas respecto a la solución general para la obtención del área del acero de la sección T que se comporta como rectangular

Electricity, hot water and cold water production from biomass. Energetic and economical analysis of the compact system of cogeneration run with woodgas from a small downdraft gasifier

AbstractWood gasification technologies to convert the biomass into fuel gas stand out. On the other hand, producing electrical energy from stationary engine is widely spread, and its application in rural communities where the electrical network doesn’t exist is very required. The recovery of exhaust gases (engine) is a possibility that makes the system attractive when compared with the same components used to obtain individual heat such as electric power. This paper presents an energetic alternative to adapt a fixed bed gasifier with a compact cogeneration system in order to cover electrical and thermal demands in a rural area and showing an energy solution for small social communities using renewable fuels. Therefore, an energetic and economical analysis from a cogeneration system producing electric energy, hot and cold water, using wooden gas as fuel from a small-sized gasifier was calculated. The energy balance that includes the energy efficiency (electric generation as well as hot and cold water system; performance coefficient and the heat exchanger, among other items), was calculated. Considering the annual interest rates and the amortization periods, the costs of production of electrical energy, hot and cold water were calculated, taking into account the investment, the operation and the maintenance cost of the equipments

Heterogeneidad en los retornos a la educación terciaria de los jóvenes de bajos ingresos: Análisis de calidad vs cantidad.

Este artículo utiliza registros administrativos de diferentes fuentes para construir un base datos de estudiantes de bajos ingresos en Colombia nacidos entre 1980 y 1990. Estos datos incluyen resultados de pruebas cognitivas, información socioeconómica en su último año de secundaria, e información sobre su trabajo, años después de la graduación de la secundaria. Evaluamos los rendimientos de la educación terciaria estimando el “efecto marginal de tratamiento” (MTE) de la inversión en educación terciaria. El MTE permite estimar un parámetro aleatorio para el rendimiento de la educación, que varía con la heterogeneidad no observada de los trabajadores. Encontramos una heterogeneidad considerable en los retornos, al punto de que, para una masa de la población, el retorno es cercano a cero. Utilizando los modelos estimados, simulamos dos tipos de políticas: una que aumenta la oferta de educación terciaria y otra que mejora la calidad de la educación secundaria. Se encuentra que una política que mejora la calidad de la educación secundaria da rendimientos similares a una política ambiciosa de incrementos en la oferta de educación terciaria.This paper uses administrative records from different sources to construct a unique data set of low-income students in Colombia born from 1980 to 1990. This data includes cognitive test results, socio-economic information at their high school final year, and information on their labor market results, many years after high school graduation. We evaluate the returns by estimating the Marginal Treatment Effect (MTE) of the tertiary investment decision. The MTE allows estimating a random parameter for tertiary education return, which varies with unobserved heterogeneity across workers. We find sizeable heterogeneity in returns, as recent literature has also identified, to the extent that for a considerable mass of the population, the return is negligible. Using the estimated models, we simulate two types of policies: one that increases the supply of tertiary education and another that enhances secondary education quality. We find that a less costly policy that improves secondary education quality gives similar returns than a more ambitious policy that increases tertiary education supply.Enfoque En Colombia, al igual que muchos países de América Latina, se observó una expansión de la educación terciaria en respuesta a la amplia cobertura de la educación secundaria durante 1991-2010. Varios estudios han reportado un incremento importante en el número de universidades en países como México, Brasil y Perú, donde la tasa de crecimiento del número de instituciones de educación superior creció entre 2005 y 2010 en 14%, 6,8% y 6,6%, respectivamente. En Colombia, de acuerdo con el Ministerio de Educación, entre 2000 y 2010 el número de instituciones de educación terciaria se incrementó en un 26%, con un incremento aun mayor en el número de programas académicos ofrecidos por estas instituciones (70%). Nuestro objetivo es evaluar cómo la expansión de estos programas académicos y universidades incrementan la probabilidad de acceder a la universidad, y de esta manera, encontrar el retorno marginal de incrementar la oferta en educación terciaria. En el mismo sentido, teniendo en cuenta la expansión en la educación secundaria, evaluamos el impacto del incremento en la calidad de la educación secundaria en la probabilidad de matricularse en la universidad, y así encontramos el retorno marginal de incrementar la calidad de la educación secundaria. Para evaluar los retornos de la inversión en educación terciaria utilizamos el enfoque del Efecto Marginal del Tratamiento (MTE). Para estimar los modelos econométricos, se construye una base de datos de la cohorte de estudiantes nacidos entre 1980-1990 y cuyas familias son de bajos ingresos económicos. Contribución: Este trabajo contribuye a la discusión sobre sí la inversión pública en educación se debe concentrar en la expansión de la educación terciaria, o si por el contrario esta se debe concentrar en la mejora en la calidad de la educación básica y secundaria. Dado que el enfoque de MTE nos permite estimar los retornos de la inversión en educación terciaria para el individuo marginal, aquel que puede ser inducido a invertir en educación como resultado de una política, podemos evaluar el retorno de políticas específicas como: la política de expansión de la oferta de educación terciaria observada en los últimos años y la política alternativa de incrementar la calidad de los colegios. Una mejora en la calidad de la educación secundaria en Colombia puede traducirse en importantes retornos de la educación terciaria. Los subsidios a la educación universitaria se basan en un sistema meritocrático, donde el examen del ICFES (Saber 11) o el examen de admisión de las universidades públicas, son el principal mecanismo de selección que determina la admisión a una institución pública. Adicionalmente, aún en el caso de las universidades privadas, el acceso a subsidios de crédito es igualmente meritocrático. De esta manera, la mejora en la calidad de la educación secundaria puede incrementar la probabilidad de acceso a la educación terciaria, especialmente de aquellos estudiantes que pertenecen a familias de bajos ingresos económicos. Resultados Nuestros resultados proveen evidencia que los retornos de una política ambiciosa de expansión de la oferta de educación terciaria son similares a los retornos de una política de incrementar la calidad de la educación secundaria. Adicionalmente, al igual que en previos estudios, encontramos que los retornos a la educación terciaria son heterogéneos; para el percentil 90 el retorno anualizado de la educación terciaria es aproximadamente de 3%, mientras que para el percentil 10 este retorno es aproximadamente del 12%. El retorno promedio anualizado es de 5,5%. Encontramos que individuos con más habilidades tienen una mayor probabilidad de invertir en educación terciaria y al mismo tiempo obtener un mayor salario en el mercado laboral. FRASE DESTACADA: Nuestros resultados proveen evidencia que los retornos de una política ambiciosa de expansión de la oferta de educación terciaria son similares a los retornos de una política de incrementar la calidad de la educación secundaria

Effectiveness of Sprayed Bioactive Fruit Extracts in Counteracting Protein Oxidation in Lamb Cutlets Subjected to a High-Oxygen MAP

High-oxygen packaging atmosphere (High-Ox-MAP) promotes meat protein oxidation and leads to texture deterioration. This study was conceived to assess the extent to which sprayed fruit extracts could inhibit the oxidative damage to proteins in lamb cutlets subjected to High-Ox-MAP (10 days/4 °C) and subsequent roasting (10 min/180 °C). Extracts from oaknut (Quercus ilex subsp. ballota; QI), rose hips (Rosa canina L.; RC), common hawthorn (Crataegus monogyna Jacq.; CM) and strawberry tree (Arbutus unedo L.; AU) were characterized for bioactive compounds (phenolic subclasses, tocopherols and ascorbic acid) and in vitro bioactivities. While the four fruits showed relevant antioxidant potential, CM had the highest phenolics and tocopherol content and that was reflected in efficient antiradical activity. The in vitro activity of this fruit to inhibit meat protein oxidation was, however, lower than that displayed by the other fruits. Taking the results altogether, CM was also found to be most efficient in protecting lamb cutlets from lipid oxidation. All fruits were able to inhibit thiols oxidation except RC, which seemed to reduce protein thiols. Among fruits, QI was the most efficient in protecting lamb cutlets against protein carbonylation as a plausible involvement of ellagitannins. The inhibition of protein oxidation by QI was reflected in significantly lower instrumental hardness in cooked lamb cutlets. Spraying lamb cutlets with extracts from QI, RC and CM improved consumers’ purchase intention after chilled storage. This antioxidant strategy seems to be a feasible and efficient solution to the pro-oxidative effects caused by High-Ox-MAP in red meat.EEA Santiago del EsteroFil: Morcuende, David. University of Extremadura. Food Technology. IPROCAR Research Institute; EspañaFil: Vallejo Torres, Christian. Technical State University of Quevedo. Food Engineering School; EcuadorFil: Ventanas, Sonia. University of Extremadura. Food Technology. IPROCAR Research Institute; EspañaFil: Martinez, Sandra L. Universidad Nacional de Santiago del Estero. Laboratorio de Calidad de la Carne; ArgentinaFil: Ruiz, Silvana Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santiago del Estero; ArgentinaFil: Estévez, Mario. University of Extremadura. Food Technology. IPROCAR Research Institute; Españ

Respiratory muscle strength in chronic stroke survivors and its relation with the 6-minute walk test

[Abstract] Objectives. To compare respiratory muscle strength in stroke survivors (SS) with that in a control group (CG) of healthy people matched by age and sex, as well as to investigate any relation between respiratory muscle strength and the distance walked during the 6-minute walk test (6MWT). Design. Cross-sectional study. Setting. This study comprised patients from a private neurological rehabilitation center and a public association for patients with acquired brain injury. Participants. Chronic SS with a diagnosis of hemiplegia/hemiparesis who were able to walk (n=30) and healthy individuals matched by sex and age (n=30) (N=60). Interventions. Not applicable. Main Outcome Measures. Respiratory muscle strength was assessed using maximal expiratory pressure (MEP) and maximal inspiratory pressure (MIP) with a pressure transducer and a diver nozzle. The distance walked during the 6MWT was also registered for both groups. The motricity index and the Scale Impact of Stroke version 16.0 were also measured in SS. Results. The Student t test revealed significantly lower values of MIP and MEP in SS than in the CG (MEP, 95.93±43.12cmH2O in SS vs 158.43±41.6cmH2O in the CG; MIP, 58.7±24.67cmH2O in SS vs 105.7±23.14cmH2O in the CG; P<.001). Moreover, these findings were clinically relevant because both MIP and MEP in SS were <60% of the predicted values. A positive correlation between the 6MWT and MIP was found using the Pearson coefficient (r=.43; P<.018). Conclusions. Respiratory muscle weakness should be considered in a holistic approach to stroke rehabilitation

RadaR (Rapid analysis of diagnostic and antimicrobial patterns in R) - an interactive open source software tool

Background: Analysing outcome and quality of care indicators for infectious patients in an entire hospital requires processing large datasets, accounting for numerous patient parameters and treatment guidelines. Rapid, reproducible and adaptable analyses usually require substantial technical expertise. We describe a dashboard tool (RadaR) allowing user-friendly, intuitive and interactive analysis of large datasets without prior in-depth knowledge. This tool was developed for studying the effect of taking blood cultures on length of stay (LOS) and antibiotic consumption in patients receiving intravenous (IV) antibiotics at an academic tertiary referral hospital. RadaR handled a modelling dataset of more than 80,000 patients (eight years, 59 sub-specialties, 35 different antibiotic agents). Materials/methods: RadaR was built in R (version 3.4.2), an open source programming language using Shiny package (version 1.0.5), a web application framework for R. Analytical graphs are generated with ggplot2 and survminer packages. The source code and additional required R packages for RadaR can be found at github.com/ceefluz/radar with a running example at ceefluz.shinyapps.io/radar. Results: RadaR visualizes analytical graphs in an interactive manner within seconds. Users can control different input variables: time of blood culture taken, study year, patient age, specialty, admission route and antibiotic agents. For a predefined grouping variable (e.g. blood cultures taken vs. not taken) in the selected patient population RadaR automatically calculates the following: LOS distribution, animated LOS distribution over time, Kaplan-Meier estimates for hospital discharge, frequencies and ratios in antibiotic prescriptions, antibiotic consumption (in DDD) and mortality. Stratification can be done for (sub-)specialties, admission route, age, gender, admissions per quarter and antibiotic agent. Moreover, multiple logistic and Cox regression analysis in RadaR allows to investigate the grouping variable further. Finally, datasets of identified groups can easily be downloaded for further analysis. Conclusions: This tool enables intuitive, rapid and reproducible quality of care pattern analysis of infectious patients without prior software experience. Hence, it facilitates understanding and communication of important trends, performances and patient outcome. We have started using RadaR to investigate blood culture use at our institution. However, due to its open source nature this tool can be easily adapted to different objectives and settings

Better antimicrobial resistance data analysis and reporting in less time

Objectives: Insights about local antimicrobial resistance (AMR) levels and epidemiology are essential to guide decision-making processes in antimicrobial use. However, dedicated tools for reliable and reproducible AMR data analysis and reporting are often lacking. We aimed to compare traditional data analysis and reporting versus a new approach for reliable and reproducible AMR data analysis in a clinical setting.Methods: Ten professionals who routinely work with AMR data were provided with blood culture test results including antimicrobial susceptibility results. Participants were asked to perform a detailed AMR data analysis in a two-round process: first using their software of choice and next using our newly developed software tool. Accuracy of the results and time spent were compared between both rounds. Finally, participants rated the usability using the System Usability Scale (SUS).Results: The mean time spent on creating the AMR report reduced from 93.7 to 22.4 min (P Conclusions: This study demonstrated the significant improvement in efficiency and accuracy in standard AMR data analysis and reporting workflows through open-source software. Integrating these tools in clinical settings can democratize the access to fast and reliable insights about local microbial epidemiology and associated AMR levels. Thereby, our approach can support evidence-based decision-making processes in the use of antimicrobials