1,386 research outputs found

    Comparative study of RPSALG algorithm for convex semi-infinite programming

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    The Remez penalty and smoothing algorithm (RPSALG) is a unified framework for penalty and smoothing methods for solving min-max convex semi-infinite programing problems, whose convergence was analyzed in a previous paper of three of the authors. In this paper we consider a partial implementation of RPSALG for solving ordinary convex semi-infinite programming problems. Each iteration of RPSALG involves two types of auxiliary optimization problems: the first one consists of obtaining an approximate solution of some discretized convex problem, while the second one requires to solve a non-convex optimization problem involving the parametric constraints as objective function with the parameter as variable. In this paper we tackle the latter problem with a variant of the cutting angle method called ECAM, a global optimization procedure for solving Lipschitz programming problems. We implement different variants of RPSALG which are compared with the unique publicly available SIP solver, NSIPS, on a battery of test problems.This research was partially supported by MINECO of Spain, Grants MTM2011-29064-C03-01/02

    Post-fledging dependence period and onset of natal dispersal in Bearded Vultures (Gypaetus barbatus): new insights from GPS satellite telemetry.

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    Utilizamos telemetría satelital para estudiar el periodo de dependencia post emplumamiento de tres individuos silvestres y seis individuos cautivos de Gypaetus barbatus. El primer vuelo tuvo lugar cuando los pollos tenían 126 ± 7 días de edad (rango  =  111-134 días) y el inicio de la dispersión ocurrió a los 193 ± 40 días desde el primer vuelo (rango  =  143-231 días). Los jóvenes permanecieron en sus áreas natales (o de liberación, en el caso de aves criadas en cautiverio) durante los primeros dos meses desde la fecha de emplumamiento. Luego, comenzaron a incrementar progresivamente la distancia a sus áreas natales; durante este tiempo, la mayoría de los desplazamientos de larga distancia (>15 km) tuvieron lugar antes del mediodía. Los tamaños de las áreas de acción registrados en este estudio fueron superiores a los descritos con anterioridad para la especie, principalmente debido a la diferencia en los métodos de rastreo empleados: la telemetría satelital permitió la detección de movimientos de larga distancia más allá del rango de medición del rastreo por radio convencional. Finalmente, la adquisición de la independencia (i.e., emancipación) se solapó con la siguiente temporada de cría de los adultos

    Self-assembly and properties of a discrete water-soluble Prussian blue analogue FeII/CoIII cube: confinement of a water molecule in aqueous solution

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    Novel types of water-soluble anionic cubic cages, K4[{CoIII(Me3-Tacn)}4{FeII(CN)6}4] and Na4[{CoIII(Me3-Tacn)}4{FeII(CN)6}4] (Me3-Tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane), were prepared by means of a mechanistically designed self-assembly process between [Co(Me3-Tacn)Cl3] and A4[FeII(CN)6] (M = Na or K), consisting of a rate-limiting outer-sphere redox step, followed by a fast substitution/inner-sphere redox reaction sequence. These compounds show remarkable stability in aqueous solution at different pH ranges, displaying neat protonation processes and reversible oxidation with peroxodisulfate to its neutral {FeIII4CoIII4} form. Furthermore, the cages behave as a robust and water-soluble molecular Prussian Blue analogue capable of encapsulating {Na-OH2}+ pairs and K+ cations in aqueous solution, with the cubic structure of the complex being preserved. Substitution of the {Na-OH2}+ pairs by K+ is easily accomplished, and the electrochemical properties of the sodium and potassium salts of the new cages have been found to be dramatically dependent on the encapsulated units

    Influence of vegetable oil sources on quality parameters of broiler meat

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    The use of different vegetable oils in animal nutrition has allowed the producer to obtain highly energetic diets at very low costs, while offering an optimum and well-appreciated product to the consumer. Nowadays, numerous efforts are taken to enrich poultry meat with polyunsaturated fatty acids (PUFA) and, especially, with omega-3 fatty acids, because of the proven benefits on human health (Kinsella et al., 1990; Knapp, 1991). But, up to now there have not been done complementary studies dealing with the influence of such nutritive improvements on the different technological characteristics of poultry meat. Besides this, there also exist few experiments dealing with the influence of the enrichment with PUFA on the subjective parameters of organoleptic quality. Those experiments are usually more related to the use of fish ingredients in animal diets. The aim of the present experiment was to study the effects of different vegetable oils (rapeseed, soybean, sunflower and linseed) on the technical, nutritive and organoleptic quality of chicken meat, and on the profiles of essential fatty acids (EFA) in the cloacal fat and in the tissues

    Experimental methodology for characterizing flame emissivity of small scale forest fires using infrared thermography techniques

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    An experimental methodology based on thermography techniques has been developed and implemented with the aim of finding emissivity values of forest fuel flames. In this paper, previous works by different authors are discussed and theoretical fundamentals of heat transfer by radiation and of infrared thermography on which experimental method relies are briefly described. Then, designed methodology, equipments, devices and experimental tests are detailed in depth. Finally, analysis procedure is pointed out and some conclusions from the study of theresults are announced.Postprint (published version

    What Do Adolescents Believe About Performing and Accepting Intimate Partner Violence Behaviors? A Reasoned Action Approach

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    Intimate partner violence against adolescent girls is of increasing political and social concern. This paper presents formative research on the reasoned action approach (RAA) to the prediction of boys’ perpetration and girls’ acceptance of four psychologically abusive behaviors. Our objectives were: (1) to identify the behavioral and normative modal beliefs behind males’ performance and girls’ acceptance of the behaviors and (2) to explore the relationship between attitudes, perceived social norm, intention and behavior. A total of 479 adolescents between 14 and 18 years of age completed questionnaires on the performance (boys) or acceptance (girls) of a specific behavior. We used a grouping process to identify modal beliefs and carried out eight exploratory multiple regression analysis (one per behavior) to study attitude and social norm as predictors of intention and behavior. Positive and negative behavioral beliefs coexist in boys’ and girls’ minds, which can reflect an unclear positioning against abusive behaviors. Positive outcomes seem to be influenced by socialization processes and love myths. Peers can be a risk factor whereas parents are a protective factor against the performance and acceptance of these behaviors. Results showed significant relationships between the constructs in the sense specified by the model. Prevention programs could benefit by: managing participants’ individual behavior, intervening separately with boys and girls, overcoming adolescents’ confusion regarding these behaviors, and targeting parents as a means of discouraging their performance and acceptance. The RAA appears a useful tool for explaining and predicting the performance and acceptance of abusive behavior

    Spatial Bayesian Modeling Applied to the Surveys of Xylella fastidiosa in Alicante (Spain) and Apulia (Italy)

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    The plant-pathogenic bacterium Xylella fastidiosa was first reported in Europe in 2013, in the province of Lecce, Italy, where extensive areas were affected by the olive quick decline syndrome, caused by the subsp. pauca. In Alicante, Spain, almond leaf scorch, caused by X. fastidiosa subsp. multiplex, was detected in 2017. The effects of climatic and spatial factors on the geographic distribution of X. fastidiosa in these two infested regions in Europe were studied. The presence/absence data of X. fastidiosa in the official surveys were analyzed using Bayesian hierarchical models through the integrated nested Laplace approximation (INLA) methodology. Climatic covariates were obtained from the WorldClim v.2 database. A categorical variable was also included according to Purcell’s minimum winter temperature thresholds for the risk of occurrence of Pierce’s disease of grapevine, caused by X. fastidiosa subsp. fastidiosa. In Alicante, data were presented aggregated on a 1 km grid (lattice data), where the spatial effect was included in the model through a conditional autoregressive structure. In Lecce, data were observed at continuous locations occurring within a defined spatial domain (geostatistical data). Therefore, the spatial effect was included via the stochastic partial differential equation approach. In Alicante, the pathogen was detected in all four of Purcell’s categories, illustrating the environmental plasticity of the subsp. multiplex. Here, none of the climatic covariates were retained in the selected model. Only two of Purcell’s categories were represented in Lecce. The mean diurnal range (bio2) and the mean temperature of the wettest quarter (bio8) were retained in the selected model, with a negative relationship with the presence of the pathogen. However, this may be due to the heterogeneous sampling distribution having a confounding effect with the climatic covariates. In both regions, the spatial structure had a strong influence on the models, but not the climatic covariates. Therefore, pathogen distribution was largely defined by the spatial relationship between geographic locations

    Influencia de la longitud de la biela en la eficiencia y biomecánica del pedaleo submáximo

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    El principal objetivo de este estudio es analizar el efecto de pequeños cambios en la longitud de la biela en el gasto energético y la técnica de pedaleo submáximo. Participaron 12 ciclistas de fondo en carretera bien entrenados, que realizaron pruebas de pedaleo a tres potencias con cadencia estable, utilizando tres longitudes de biela (en orden aleatorio). Sus bicicletas fueron exactamente reproducidas en un ergómetro que medía el torque ejercido sobre la biela izquierda y derecha de forma independiente. Simultáneamente se registró cinemática 2D de la pierna derecha y el gasto energético al pedalear (eficiencia gruesa). Los resultados muestran que los cambios en la longitud de la biela no tuvieron efecto en la eficiencia gruesa, pero sí en las variables biomecánicas. Una biela de mayor longitud provocó una pérdida de eficiencia mecánica y un aumento en la flexión y el rango de movimiento de la cadera y la rodilla, sin cambios en el tobillo. Aunque estos cambios no fueron lo suficientemente importantes para alterar la eficiencia gruesa, sí que podrían tener implicaciones negativas a largo plazo (peor técnica de pedaleo y riesgo de lesión). En conclusión, el efecto de pequeños cambios en la longitud de la biela, que serían asumibles por ciclistas de competición, producen alteraciones en la biomecánica de pedaleo, pero no en su eficiencia gruesa. Futuros estudios deben abordar los efectos a largo plazo de estos cambios.The main purpose of this study was to analyze the effects of small changes in crank length on gross efficiency and pedaling technique during submaximal cycling. Twelve well-trained road cyclists participated. They pedaled at three power outputs and steady cadence with three crank lengths (in a randomized order). Their bicycles were exactly reproduced on an ergometer where crank torque of the left and right legs were independently registered. 2D kinematic of the right leg and energy cost (gross efficiency) were recorded. The results showed that changes in crank length had no effect on the gross efficiency, but had effect on the biomechanical variables. A longer crank caused a decreased in mechanical efficiency and an increase in the flexion and range of movement of the hip and the knee, without changes in the ankle. These alterations were not significant enough to alter the gross efficiency, but they could have negative long-term implications (worse pedaling technique and possible injuries). In conclusion, the small changes in crank arm length which are feasible for competitive cyclists affected cycling biomechanics, but not gross efficiency. Future studies should study long-term effects of these changes.Peer Reviewe

    Solving Man-Induced Large-Scale Conservation Problems: The Spanish Imperial Eagle and Power Lines

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    [Background] Man-induced mortality of birds caused by electrocution with poorly-designed pylons and power lines has been reported to be an important mortality factor that could become a major cause of population decline of one of the world rarest raptors, the Spanish imperial eagle (Aquila adalberti). Consequently it has resulted in an increasing awareness of this problem amongst land managers and the public at large, as well as increased research into the distribution of electrocution events and likely mitigation measures.[Methodology/Principal Findings] We provide information of how mitigation measures implemented on a regional level under the conservation program of the Spanish imperial eagle have resulted in a positive shift of demographic trends in Spain. A 35 years temporal data set (1974–2009) on mortality of Spanish imperial eagle was recorded, including population censuses, and data on electrocution and non-electrocution of birds. Additional information was obtained from 32 radio-tracked young eagles and specific field surveys. Data were divided into two periods, before and after the approval of a regional regulation of power line design in 1990 which established mandatory rules aimed at minimizing or eliminating the negative impacts of power lines facilities on avian populations. Our results show how population size and the average annual percentage of population change have increased between the two periods, whereas the number of electrocuted birds has been reduced in spite of the continuous growing of the wiring network.[Conclusions] Our results demonstrate that solving bird electrocution is an affordable problem if political interest is shown and financial investment is made. The combination of an adequate spatial planning with a sustainable development of human infrastructures will contribute positively to the conservation of the Spanish imperial eagle and may underpin population growth and range expansion, with positive side effects on other endangered species.P. López-López was supported by FPU grant of the Spanish Ministerio de Educación (reference AP2005-0874) and wrote this paper during a pre-doctoral stay at Doñana Biological Station (CSIC) in Sevilla, Spain. The funders of this study (Spanish Ministry of Education, Natural Research Ltd. and Junta de Andalucía) had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe
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