A DECOMPOSITION PROCEDURE BASED ON APPROXIMATE NEWTON DIRECTIONS

The efficient solution of large-scale linear and nonlinear optimization problems may require exploiting any special structure in them in an efficient manner. We describe and analyze some cases in which this special structure can be used with very little cost to obtain search directions from decomposed subproblems. We also study how to correct these directions using (decomposable) preconditioned conjugate gradient methods to ensure local convergence in all cases. The choice of appropriate preconditioners results in a natural manner from the structure in the problem. Finally, we conduct computational experiments to compare the resulting procedures with direct methods, as well as to study the impact of different preconditioner choices.

Estimation of kinetic parameters in a chromatographic separation model via Bayesian inference

A modelagem de processos de adsorção tem sido empregada com frequência nas indústrias químicas, petroquímicas e refinarias, por exemplo para separação e purificação de misturas em unidade de Leito Móvel Simulado (LMS). Na representação matemática do modelo, a determinação de parâmetros é um passo importante para o projeto de condições cromatográficas para a separação contínua, em processos do tipo LMS. Este trabalho tem por objetivo a análise de estimativa de parâmetros em processos de adsorção, usando um sistema cromatográfico com uma coluna, para a separação das substâncias Glicose e Frutose. Investiga-se o uso da abordagem Bayesiana, através de métodos de Monte Carlo via Cadeias de Markov (MCMC), assim como o uso da abordagem da máxima verossimilhança, utilizando duas técnicas estocásticas diferentes, o Algoritmo de Colisão de Partículas (PCA - Particle Collision Algorithm), e o Algoritmo de Otimização por Enxame de Partículas (PSO - Particle Swarm Optimization) para executar a tarefa de minimização da função objetivo. Diferentes casos são apresentados com o objetivo de analisar a significância estatística das estimativas obtidas para os parâmetros, fazendo-se uma comparação crítica entre a solução via inferência Bayesiana e via minimização da função objetivo com métodos estocásticos. Os resultados obtidos demonstram que o uso da abordagem Bayesiana fornece uma proposta vantajosa para a estimativa de parâmetros em transferência de massa, oferecendo resultados com maior riqueza de informação estatística.The modeling of adsorption processes appears quite frequently in the chemical industry, petrochemical plants and refineries, for example for separation and purification of mixtures in Simulated Moving Bed (SMB) units. In the mathematical formulation, the accurate determination of the model parameters is an important step for the design of chromatographic conditions for continuous separation in SMB processes. This work is aimed at the estimation of the model parameters in adsorption processes, using a chromatographic column for the separation of glucose and fructose. The Bayesian framework for inverse problems is investigated through the implementation of Markov Chain Monte Carlo methods (MCMC) and a critical comparison against the classical Maximum Likelihood approach, with the minimization of the objective function via two different stochastic techniques, namely the Particle Collision Algorithm (PCA), and the Particle Swarm Optimization (PSO) is performed. Different cases are presented in order to investigate the statistical significance of the estimates obtained, and perform comparisons between the solution via Bayesian inference and via the minimization of the objective function with the stochastic methods. The results demonstrate that the Bayesian approach employs less computational effort to achieve estimates with comparable statistical information.Peer Reviewe

Newborn patients exhibit an unusual pattern of interleukin 10 and interferon γ serum levels in response to cardiac surgery

AbstractObjective: The aim of this study was to determine the clinical significance of serum levels of interleukin 10 and interferon γ in pediatric patients undergoing cardiopulmonary bypass. Methods: We divided the patients into 2 groups: 8 neonates and 19 nonnewborn children. Interleukin 10 and interferon γ serum levels were quantified before sternotomy, at admission to the pediatric intensive care unit (30 minutes postoperatively), 24 hours after the onset of the operation, and 3 days after the operation. Results: Newborn patients displayed significantly greater amounts of serum interleukin 10 than older children, not only in regard to the peak level achieved but also at every postoperative time point analyzed. In contrast, no significant changes in interferon γ serum levels were observed in neonates at any time point, whereas nonnewborn pediatric patients showed a significant increase in interferon γ serum concentrations immediately after the operation. This unusual pattern of cytokine response in newborn patients was not associated with modifications in cortisol serum levels. Furthermore, although neonates had significantly different surgical and clinical variables than did the nonnewborn pediatric patients, the variation in interleukin 10 production in neonates could not be accounted for by differences in the magnitude of surgical injury. In the group of neonates, there were significant positive correlations between peak interleukin 10 serum levels and both partial pressure of arterial oxygen/fraction of inspired oxygen ratio and postoperative body weight gain. Conclusions: Newborn patients undergoing cardiopulmonary bypass exhibit a distinctive biologic response pattern characterized by high levels of serum interleukin 10 without changes in serum interferon γ. This cytokine imbalance could have potential clinical implications.J Thorac Cardiovasc Surg 2002;123:451-

Spectral Classification; Old and Contemporary

Beginning with a historical account of the spectral classification, its refinement through additional criteria is presented. The line strengths and ratios used in two dimensional classifications of each spectral class are described. A parallel classification scheme for metal-poor stars and the standards used for classification are presented. The extension of spectral classification beyond M to L and T and spectroscopic classification criteria relevant to these classes are described. Contemporary methods of classifications based upon different automated approaches are introduced.Comment: To be published in "Principles and Perspectives in Cosmochemistry" Lecture Notes on Kodai School on Synthesis of Elements in Stars: Ed Aruna Goswami & Eswar Reddy, Springer Verlag, 2009, 17 pages, 10 figure

Effect of an alcohol-free beer enriched with isomaltulose and a resistant dextrin on insulin resistance in diabetic patients with overweight or obesity

Background & aims: The quality of carbohydrates has an essential role in nutritional management of type 2 diabetes mellitus (T2DM) because of its substantial impact on glucose homeostasis. Alcohol-free beer has beneficial bioactive components but it has a relatively high glycemic-index so its consumption is restricted in diabetic subjects. We aimed to explore the effect of an alcohol-free beer with modified carbohydrate composition almost completely eliminating maltose and adding isomaltulose (16.5 g/day) and a resistant maltodextrin (5.28 g/day) in comparison to a regular alcohol-free beer on glycemic control of diabetic subjects with overweight or obesity. Design: We randomized 41 subjects into two groups: a) consumption of 66 cL/day of; regular alcohol-free beer for the first 10 weeks and 66 cL/day of alcohol-free beer with modified carbohydrate composition for the next 10 weeks; b) the same described intervention in opposite order. There was a washout period for 6–8 weeks between the two interventions. Participants were counseled to adhere to a healthy diet for cardiovascular health and to increase physical activity. Clinical, biochemical, anthropometric, lifestyle and satiety assessments were performed at the beginning and at the end of each period. Results: Subjects showed significantly weight loss after the two ten weeks periods (-1.69 ± 3.21% and -1.77 ± 3.70% after experimental and regular alcohol-free beers, respectively, P = 0.881). Glucose and glycated hemoglobin did not significantly change after any period. Insulin concentrations and HOMA-IR significantly decreased (-11.1 [–21.3-4.64]% and -1.92 ± 32.8% respectively) after the intake of experimental alcohol-free beer but not after regular alcohol-free beer. Reductions remained statistically significant after adjusting for weight loss, energy intake, physical activity and intervention order. Subjects reported higher satiety scores after consuming experimental alcohol-free beer. Conclusions: An alcohol-free beer including the substitution of regular carbohydrates for low doses of isomaltulose and the addition of a resistant maltodextrin within meals led to an improvement in insulin resistance in subjects with T2DM and overweight or obesity. Clinical trial registration: The clinical trial has been registered in ClinicalTrials.gov (Identifier: NCT03337828)

A new tool based on artificial intelligence and GIS for preventive conservation of heritage buildings

This paper describes a new predictive model for preventive conservation of buildings. It allows for multiscenarios of several hazards, assessments of environmental risks, and the use level of buildings together with cultural val-ues of monuments. This modeling approach is based on fuzzy logic and geographic information system available to organizations dedicated to the restoration and rehabilitation in Spain. This system has a transversal development that includes urban, architectural, cultural heritage value, and the analysis of environmental and sociodemographic situations around the monuments. This new tool allows for decision making based on scientific criteria and minimizes risklosses of cultural asset

Revision and 90-day mortality following hip arthroplasty in patients with inflammatory arthritis and ankylosing spondylitis enrolled in the National Joint Registry for England and Wales

Aim: To assess revision rates and postoperative mortality in patients undergoing hip arthroplasty (HA) for inflammatory arthritis compared to hip osteoarthritis (OA). Methods: The analysis was conducted among cases of HA that were recorded in the National Joint Registry for England and Wales (NJR) between April 2003 and December 2012 and linked to Office for National Statistics mortality records. Procedures were identified where the indication for surgery was listed as seropositive rheumatoid arthritis (RA), ankylosing spondylitis (AS), other inflammatory arthritis (otherIA), or OA. 5-year revision risk and 90-day postoperative mortality according to indication were compared using Cox regression models adjusted for age, sex, American Society of Anaesthesiologists (ASA) grade, year of operation, implant type, and surgical approach. Results: The cohort included 1457 HA procedures conducted for RA, 615 for AS, 1000 for otherIA, and 183,108 for OA. When compared with OA, there was no increased revision risk for any form of inflammatory arthritis (adjusted HRs: RA: 0.93 (0.64–1.35); AS: 1.14 (0.73–1.79); otherIA: 1.08 (0.73–1.59)). Postoperative 90-day mortality was increased for RA when compared with OA (adjusted HR: 2.86 (1.68–4.88)), but not for AS (adjusted HR: 1.56 (0.59–4.18)) or otherIA (adjusted HR: 0.64 (0.16–2.55)). Conclusions: The revision risk in HA performed for all types of inflammatory arthritis is similar to that for HA performed for OA. The 3-fold increased risk of 90-day mortality in patients with RA compared with OA highlights the need for active management of associated comorbidities in RA patients during the perioperative period

Surgical site infection following surgery for hand trauma: a systematic review and meta-analysis

Surgical site infection is the most common healthcare-associated infection. Surgical site infection after surgery for hand trauma is associated with increased antibiotic prescribing, re-operation, hospital readmission and delayed rehabilitation, and in severe cases may lead to amputation. As the risk of surgical site infection after surgery for hand trauma remains unclear, we performed a systematic review and meta-analysis of all primary studies of hand trauma surgery, including randomized controlled trials, cohort studies, case-control studies and case series. A total of 8836 abstracts were screened, and 201 full studies with 315,618 patients included. The meta-analysis showed a 10% risk of surgical site infection in randomized control trials, with an overall risk of 5% when all studies were included. These summary statistics can be used clinically for informed consent and shared decision making, and for power calculations for future clinical trials of antimicrobial interventions in hand trauma

Evaluación de los costes de mantenimiento y restauración de edificios patrimoniales

En las últimas décadas, no se han adoptado protocolos de mantenimiento adecuados para la conservación y rehabilitación del patrimonio cultural. En España, el mantenimiento de estos edificios tiene, comúnmente, una naturaleza reactiva, estando condicionada por criterios subjetivos y por la existencia de fondos disponibles para la realización de las acciones de rehabilitación. Por tanto, es fundamental que los gestores del patrimonio construido tengan información relevante que ayude a tomar decisiones sobre la prioridad de intervención y las acciones preventivas a realizar en edificios patrimoniales. Existen cada vez más estudios relacionados con la definición de estrategias de mantenimiento adecuadas, que permitan mejorar el estado de conservación del patrimonio construido, con especial foco en la optimización de costos de mantenimiento empleados durante el ciclo de vida de estos edificios. Este trabajo identifica los factores que condicionan la decisión de intervenir en un conjunto de edificios patrimoniales, localizados en el sur de España. Se analizan las acciones de mantenimiento realizadas en un conjunto de 20 iglesias parroquiales y sus costes durante un período de 11 años (entre 2005 y 2015). En este estudio se evalúa la eficacia de las acciones realizadas, identificando los puntos fuertes y débiles de las intervenciones y estrategias adoptadas a lo largo del período de tiempo analizado. Los resultados obtenidos demuestran que las acciones de naturaleza reactiva deben ser minimizadas, para reducir los costes de mantenimiento. El conocimiento adquirido con las estrategias adoptadas en el pasado permite proporcionar información relevante para la planificación adecuada de futuras estrategias de mantenimient