High order structure preserving explicit methods for solving linear-quadratic optimal control problems

[EN] We consider the numerical integration of linear-quadratic optimal control problems. This problem requires the solution of a boundary value problem: a non-autonomous matrix Riccati differential equation (RDE) with final conditions coupled with the state vector equation with initial conditions. The RDE has positive definite matrix solution and to numerically preserve this qualitative property we propose first to integrate this equation backward in time with a sufficiently accurate scheme. Then, this problem turns into an initial value problem, and we analyse splitting and Magnus integrators for the forward time integration which preserve the positive definite matrix solutions for the RDE. Duplicating the time as two new coordinates and using appropriate splitting methods, high order methods preserving the desired property can be obtained. The schemes make sequential computations and do not require the storrage of intermediate results, so the storage requirements are minimal. The proposed methods are also adapted for solving linear-quadratic N-player differential games. The performance of the splitting methods can be considerably improved if the system is a perturbation of an exactly solvable problem and the system is properly split. Some numerical examples illustrate the performance of the proposed methods.The author wishes to thank the University of California San Diego for its hospitality where part of this work was done. He also acknowledges the support of the Ministerio de Ciencia e Innovacion (Spain) under the coordinated project MTM2010-18246-C03. The author also acknowledges the suggestions by the referees to improve the presentation of this work.Blanes Zamora, S. (2015). High order structure preserving explicit methods for solving linear-quadratic optimal control problems. 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Health-related quality of life of primary caregivers of persons with paraplegia

Study Design: A cross-sectional descriptive study was performed with structured questionnaires and interviews conducted with 60 primary caregivers of persons with paraplegia (T1 to S2) owing to traumatic spinal cord injury (SCI).Objectives: the purpose of this study was the assessment of the health-related quality of life (HRQoL) of primary caregivers of persons with paraplegia owing to traumatic SCI.Setting: Sa oSa Paulo, SP, Brazil.Methods: the HRQoL was assessed by the Short Form-36 (SF-36) health survey questionnaire and caregiver burden was evaluated by the Caregiver Burden Scale (CBS).Results: Among 60 caregivers evaluated, 49 (81.7%) were female, with mean age of 35.8 (SD = 12.91) years, 16 (26.6%) being wives and 14 (23.4%) sisters of pe rsons with paraplegia. It was found that the caregivers spend an average of 11.3 h/ day caring for individuals with paraplegia. Twenty-three caregivers (38.3%) had a chronic disease and 32 (53.3%) were sole caregivers taking upon themselves the full responsibility of caring for the persons with paraplegia. the subjects reported lower scores on bodily pain and vitality than the other dimensions of the SF-36. the mean global CBS score was 1.71 (SD = 0.50) and mean scores for each dimension ranged from 1.39 (SD = 0.64) for emotional involvement to 2.44 (SD = 0.79) for environment dimension.Conclusion: the primary caregivers of spinal cord-injured persons reported low scores on all of the SF-36 and CBS dimensions, bodily pain and vitality being the SF-36 dimensions that received the lowest scores.Universidade Federal de São Paulo, Discipline Plast Surg, Div Plast Surg, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Nursing, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Discipline Plast Surg, Div Plast Surg, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Nursing, BR-04023062 São Paulo, BrazilWeb of Scienc

High-throughput variable-to-fixed entropy codec using selective, stochastic code forests

Efficient high-throughput (HT) compression algorithms are paramount to meet the stringent constraints of present and upcoming data storage, processing, and transmission systems. In particular, latency, bandwidth and energy requirements are critical for those systems. Most HT codecs are designed to maximize compression speed, and secondarily to minimize compressed lengths. On the other hand, decompression speed is often equally or more critical than compression speed, especially in scenarios where decompression is performed multiple times and/or at critical parts of a system. In this work, an algorithm to design variable-to-fixed (VF) codes is proposed that prioritizes decompression speed. Stationary Markov analysis is employed to generate multiple, jointly optimized codes (denoted code forests). Their average compression efficiency is on par with the state of the art in VF codes, e.g., within 1% of Yamamoto et al.\u27s algorithm. The proposed code forest structure enables the implementation of highly efficient codecs, with decompression speeds 3.8 times faster than other state-of-the-art HT entropy codecs with equal or better compression ratios for natural data sources. Compared to these HT codecs, the proposed forests yields similar compression efficiency and speeds

High-order splitting methods for separable non-autonomous parabolic equations

We consider the numerical integration of non-autonomous separable parabolic equations using high order splitting methods with complex coefficients (methods with real coeffi- cients of order greater than two necessarily have negative coefficients). We propose to consider a class of methods that allows us to evaluate all time-dependent operators at real values of the time, leading to schemes which are stable and simple to implement. If the system can be considered as the perturbation of an exactly solvable problem and the flow of the dominant part is advanced using real coefficients, it is possible to build highly efficient methods for these problems. We show the performance of this class of methods on several numerical examples and present some new improved schemesThe authors thank the referees for their suggestions to improve the presentation of this work. The work of Sergio Blanes has been supported by Ministerio de Ciencia e Innovacion (Spain) under project MTM2010-18246-C03 and the Ministerio de Educacion, Cultura y Deporte, under Programa Nacional de Movilidad de Recursos Humanos del Plan Nacional de I-D+i 2008-2011 (PRX12/00547). The work of Muaz Seydaoglu has been supported by the Turkish Council of High Education through a grant for visiting the Instituto de Matematica Multidisciplinar at the Polytechnic University of Valencia where this work was carried out.Seydaoglu, M.; Blanes Zamora, S. (2014). High-order splitting methods for separable non-autonomous parabolic equations. Applied Numerical Mathematics. 84:22-32. https://doi.org/10.1016/j.apnum.2014.05.004S22328

Public health competencies and contents in Spanish university degree programmes of Veterinary Medicine

Objetivo: Consensuar las competencias profesionales de salud pública que deben adquirir los/las estudiantes en el Grado en Veterinaria y los contenidos fundamentales que deben incluir los programas de salud pública según el criterio de docentes de salud pública del Grado en Veterinaria representantes de distintas universidades españolas. Métodos: Se organizó la 3 ª Reunión del Foro de Profesorado Universitario de Salud Pública en la Facultad de Veterinaria de la Universidad de Córdoba (12-13 de enero de 2016). Participaron 42 docentes de nueve universidades españolas con Grado en Veterinaria y se distribuyeron en cinco grupos durante tres sesiones de trabajo para identificar y clasificar las competencias propias del grado, proponer contenidos de salud pública para las competencias identificadas, y organizar los contenidos en bloques temáticos. Los resultados se discutieron en distintas sesiones plenarias hasta alcanzar acuerdos. Resultados: El mayor número de competencias identificadas corresponde a actividades de las funciones «Valorar las necesidades de salud de la población» y «Desarrollar políticas de salud». El programa resultante incluye contenidos básicos organizados en cinco bloques: 1) Fundamentos de salud pública; 2) Estudio e investigación en salud pública; 3) Producción, sanidad animal y medio ambiente; 4) Seguridad alimentaria; y 5) Educación sanitaria y comunicación. Conclusiones: Los acuerdos alcanzados pueden ser un buen punto de partida para orientar una propuesta formativa en salud pública del grado para los futuros profesionales de veterinaria.Objective: To reach a consensus among public health faculty from various Spanish universities about the core public health competencies that should be integrated into the Veterinary Medicine degree training. Methods: The 3 rd Forum of University Professors of Public Health was held at the School of Veterinary Medicine of the University of Cordoba (12-13 January 2016). Forty-two university professors and lecturers from nine Spanish universities with veterinary degrees participated in the forum. They were divided into five working groups during three working sessions to identify and classify core public health competencies for the Veterinary Medicine degree, propose public health contents for the identified competencies and organize such contents in thematic blocks. The results were discussed in different plenary sessions. Results: The highest number of core competencies was identified in the activities related to the following public health functions: «Assessment of the population's health needs» and «Developing health policies». The final programme included basic contents organized into five units: 1) Fundamentals of public health; 2) Study and research in public health; 3) Production, animal health and environment; 4) Food security; and 5) Health education. Conclusions: The public health core competencies and contents identified in this Forum may be considered as a starting point to update public health training programmes for future veterinary professionals

Computer versus cardiologist: Is a machine learning algorithm able to outperform an expert in diagnosing a phospholamban p.Arg14del mutation on the electrocardiogram?

Background Phospholamban (PLN) p.Arg14del mutation carriers are known to develop dilated and/or arrhythmogenic cardiomyopathy, and typical electrocardiographic (ECG) features have been identified for diagnosis. Machine learning is a powerful tool used in ECG analysis and has shown to outperform cardiologists. Objectives We aimed to develop machine learning and deep learning models to diagnose PLN p.Arg14del cardiomyopathy using ECGs and evaluate their accuracy compared to an expert cardiologist. Methods We included 155 adult PLN mutation carriers and 155 age- and sex-matched control subjects. Twenty-one PLN mutation carriers (13.4%) were classified as symptomatic (symptoms of heart failure or malignant ventricular arrhythmias). The data set was split into training and testing sets using 4-fold cross-validation. Multiple models were developed to discriminate between PLN mutation carriers and control subjects. For comparison, expert cardiologists classified the same data set. The best performing models were validated using an external PLN p.Arg14del mutation carrier data set from Murcia, Spain (n = 50). We applied occlusion maps to visualize the most contributing ECG regions. Results In terms of specificity, expert cardiologists (0.99) outperformed all models (range 0.53–0.81). In terms of accuracy and sensitivity, experts (0.28 and 0.64) were outperformed by all models (sensitivity range 0.65–0.81). T-wave morphology was most important for classification of PLN p.Arg14del carriers. External validation showed comparable results, with the best model outperforming experts. Conclusion This study shows that machine learning can outperform experienced cardiologists in the diagnosis of PLN p.Arg14del cardiomyopathy and suggests that the shape of the T wave is of added importance to this diagnosis

Percepción de los escolares sobre los accidentes y las lesiones accidentales

Antecedentes/Objetivos: Las lesiones no intencionales constituyen la primera causa de muerte en la población infantil española (1-14 años) con una tasa de mortalidad de 6,5 por 100.000 niñas/os. Según datos de la Encuesta Nacional de Salud de 2006, la incidencia acumulada de lesiones accidentales en el último año previo a la encuesta fue de 10,6% de las/os niños entrevistadas/os, más frecuente en niños (51,4%) que en niñas (48,6%). Los accidentes se produjeron con mayor frecuencia en casa (29%), en la calle (23%) y en la escuela (22%). Pocos estudios han investigado la perspectiva de las/os niñas/os sobre las lesiones accidentales que sufren. El objetivo del estudio es explorar, describir y categorizar las percepciones de las/os niñas/os sobre las lesiones accidentales y las explicaciones de los accidentes que hayan podido experimentar. Métodos: Estudio exploratorio mediante análisis cualitativo sobre la percepción de salud de la población infantil. Los datos se obtuvieron de 6 grupos de discusión de entre 8 a 10 niños/as formados en 2006 mediante muestreo teórico intencional de niños/as de edades entre 8 y 12 años de 3º y 6º curso de primaria de colegios públicos y concertados de Alicante con los criterios de inclusión: Centro público/concertado; Zona centro o residencial/zona de clase trabajadora; Niños/niñas/grupo mixto; Tercero y Sexto de primaria. Los discursos fueron grabados, transcritos y posteriormente analizados usando el programa ATLASTI.v.4.1 y aplicando los principios de la grounded theory. Dos investigadores identificaron una estructura temática y un proceso de codificación abierta revisada por un tercero para validar el proceso y determinar las categorías y subcategorías resultantes. Resultados: Los accidentes fue un tema emergente del análisis del discurso. Se identificaron las categorías y subcategorías: Conceptualización de accidente (a. Oposición a salud, “Un niño sano no se rompe nada” b. Asociado a enfermedad “Cuando te rompes la mano o la muñeca” c. Suceso inevitable “Es algo que no se puede prevenir”) Causa y tipo de lesiones (“Por mucho que me caiga sólo me he hecho moraos”) Lugares donde se producen accidentes (a. Escuela “El patio es plano y cuando juegas al futbol algún niño se cae” b. Otros “Me hice una fisura en la calle”) Sugerencias para evitar accidentes (a. Espacios escolares “Arreglar el suelo del patio” b. Conductas personales “Tener más cuidado”). Conclusiones: La población infantil sabe identificar los accidentes como problema de salud. Los percibe como inevitables aunque propone formas de evitarlos. Ayudar a los escolares a identificar las causas de los accidentes puede eliminar su percepción de inevitabilidad y fortalecer su capacidad para afrontarlos.Escuela Valenciana de Estudios en Salud. Generalitat Valenciana 044/2006

A jade pished hand-axe from Tubino's Cection (Valencina de la Concepción Local Museum, Sevilla, Spain)

A pished axe donated to the Valencina de la Concepción Museum (Seville, Spain) in November 2010, and that had belonged to Francisco María Tubino y Oliva's (1833-1888) personal clection, is studied. Although the exact provenance of this object is unknown, there are reasons to think that it might have been found on some archaẽogical site of the Seville province. Through the application of two different analytical techniques (XRD, DCμRS), this axe is identified as a jade-jadeite of purity above 95 ml%, which necessarily implies it came from the Alps. In the conclusions a discussion of this artifact is made in terms of long distance contact in Iberian Late Prehistory.Peer Reviewe