Rol de los sistemas de producción de aves y cerdos de traspatio en la emergencia y mantención de patógenos zoonóticos en Chile

En Chile la producción de aves y cerdos se concentra en unidades de producción industrial con altosestándares de productividad, calidad y bioseguridad. Este sector industrial concentra más del 85% de laspoblaciones de aves y cerdos en el país.Sin embargo, existen otras formas de producción animal. Una de ellas está en manos de pequeñosproductores, y se denomina como "producción animal de traspatio", que en Chile estaría representada pormás de 150 mil productores, 3,7 millones de aves y 400 mil cerdos.Los sistemas de producción animal de traspatio (SPT) son considerados como la forma de producción animalmás común a nivel mundial. Además, se reconoce que la mantención de estas unidades productivas juega unrol relevante para subsistencia de pequeños agricultores y su grupo familiar, siendo principalmente uncomplemento a las fuentes de alimentación que generan recursos económicos esporádicos. Sin embargo, segeneraliza a estas unidades productivas como poseedoras de severas deficiencias en bioseguridad

Pathogenesis and clinical approaches to anticonvulsant hypersensitivity syndrome: current state of knowledge.

Anticonvulsant hypersensitivity syndrome (AHS) is a rare, but severe and potentially fatal, adverse reaction that occurs in patients who are treated with commonly used older anticonvulsant drugs (phenytoin, carbamazepine and phenobarbital) and/or with some newer agents (lamotrigine). Paediatric patients are at an increased risk for the development of AHS for the higher incidence of seizure disorder in the first decade of life. Hypersensitivity reactions range from simple maculopapular skin eruptions to a severe life-threatening disorder. AHS is typically associated with the development of skin rash, fever and internal organ dysfunctions. Recent evidence suggests that AHS is the result of a chemotoxic and immunologically-mediated injury, characterized by skin and mucosal bioactivation of antiepileptic drugs and by major histocompatibility complex-dependent clonal expansion of T cells. Early recognition of AHS and withdrawal of anticonvulsant therapy are essential for a successful outcome. In vivo and vitro tests can be helpful for the diagnosis that actually depends essentially on clinical recognition

Backyard poultry production in Chile: animal health management and contribution to food access in an upper middle-income country

Backyard production systems (BPS) that involve poultry are a good way to improve food security and poverty alleviation. Few studies have been carried out to quantify the contribution of poultry production to these households and the constraints they might face if a priority animal disease enters these systems. This study aims to characterize the poultry-rearing BPS in central Chile and to identify socio-economic factors associated to households’ consumption of poultry. Data was collected from 384 BPS through a face-to-face semi-structured questionnaire. Value chain framework associated with BPS poultry rearing and cash flow analysis of BPS was done to identify the inputs/outputs of the system and to know the profitability of the system. Multiple linear regression was performed to identify the BPS and household factors associated to poultry consumption. The results of this study suggest that BPS in central Chile have biosecurity deficiencies such as: lack of confinement, lack of veterinary assistance and incorrect handling of dead animals. Cash flow analysis indicated that 62% of the BPS had a positive balance from production. Distance to closest market and per capita income were factors associated to poultry value to farmers. Different factors were significant predictors of household poultry consumption. Positive predictors of consumption were identified as: (i) older owners, (ii) higher transportation price to closest market, (iii) larger flock size (iv) birds raised by women and (v) owning a car. On the contrary, (i) higher per capita income and (ii) bigger household size predicted a reduction in consumption. The results indicate the importance of BPS to low-income families and those living in remote areas while also highlighting the vulnerability of these systems to disease risks

Theoretical and practical convergence of a self-adaptive penalty algorithm for constrained global optimization

This paper proposes a self-adaptive penalty function and presents a penalty-based algorithm for solving nonsmooth and nonconvex constrained optimization problems. We prove that the general constrained optimization problem is equivalent to a bound constrained problem in the sense that they have the same global solutions. The global minimizer of the penalty function subject to a set of bound constraints may be obtained by a population-based meta-heuristic. Further, a hybrid self-adaptive penalty firefly algorithm, with a local intensification search, is designed, and its convergence analysis is established. The numerical experiments and a comparison with other penalty-based approaches show the effectiveness of the new self-adaptive penalty algorithm in solving constrained global optimization problems.The authors would like to thank the referees, the Associate Editor and the Editor-in-Chief for their valuable comments and suggestions to improve the paper. This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Funda¸c˜ao para a Ciˆencia e Tecnologia within the projects UID/CEC/00319/2013 and UID/MAT/00013/2013.info:eu-repo/semantics/publishedVersio

On a smoothed penalty-based algorithm for global optimization

This paper presents a coercive smoothed penalty framework for nonsmooth and nonconvex constrained global optimization problems. The properties of the smoothed penalty function are derived. Convergence to an ε -global minimizer is proved. At each iteration k, the framework requires the ε(k) -global minimizer of a subproblem, where ε(k)→ε . We show that the subproblem may be solved by well-known stochastic metaheuristics, as well as by the artificial fish swarm (AFS) algorithm. In the limit, the AFS algorithm convergence to an ε(k) -global minimum of the real-valued smoothed penalty function is guaranteed with probability one, using the limiting behavior of Markov chains. In this context, we show that the transition probability of the Markov chain produced by the AFS algorithm, when generating a population where the best fitness is in the ε(k)-neighborhood of the global minimum, is one when this property holds in the current population, and is strictly bounded from zero when the property does not hold. Preliminary numerical experiments show that the presented penalty algorithm based on the coercive smoothed penalty gives very competitive results when compared with other penalty-based methods.The authors would like to thank two anonymous referees for their valuable comments and suggestions to improve the paper. This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Fundac¸ao para a Ci ˜ encia e Tecnologia within the projects UID/CEC/00319/2013 and ˆ UID/MAT/00013/2013.info:eu-repo/semantics/publishedVersio

An algorithm for the nonlinear programming problem of the railway Yield Management

In this paper we consider the problem of solving a special class of nonlinear constrained optimization problems. The study of this class of problems has been motivated by a practical application, namely the railway yield management problem. The aim of this paper is to define a nonlinear minimization algorithm which exploits as much as possible the structure of the problems under consideration. The approach followed is to transform the original constrained problem into the unconstrained minimization of a continuously differentiable merit function whose unconstrained minimizers give a solution of the original constrained problem. In comparison with the merit functions proposed before in the literature, this new merit function has the distinguishing feature of taking full advantage of the particular structure of the constraints of the original problem. Furthermore we show also that it is possible to define descent search directions which are particularly well suited for the proposed merit..

Cecità e ipovisione in Italia

Gli Autori hanno eseguito uno studio epidemiologico sulla cecità e ipovisione in Italia basandosi su dati ISTAT, dati INPS, dati UICI

An Augmented Lagrangian Method Exploiting an Active-Set Strategy and Second-Order Information

In this paper, we consider nonlinear optimization problems with nonlinear equality constraints and bound constraints on the variables. For the solution of such problems, many augmented Lagrangian methods have been defined in the literature. Here, we propose to modify one of these algorithms, namely ALGENCAN by Andreani et al., in such a way to incorporate second-order information into the augmented Lagrangian framework, using an active-set strategy. We show that the overall algorithm has the same convergence properties as ALGENCAN and an asymptotic quadratic convergence rate under suitable assumptions. The numerical results confirm that the proposed algorithm is a viable alternative to ALGENCAN with greater robustness