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El propósito de este estudio, de carácter transversal y multicéntrico, es indagar en las experiencias didácticas en materia de sostenibilidad llevadas a cabo por el profesorado de Educación Secundaria Obligatoria (ESO) que ejerce su docencia en la Comunidad de Madrid. Cuenta con un muestreo no probabilístico por conveniencia, compuesto por un total de 153 participantes. Se elaboró un cuestionario a través de la plataforma Google Forms, el cual fue sometido al proceso de validación de expertos y de fiabilidad. La información obtenida sobre las experiencias didácticas desarrolladas por el profesorado de ESO en su práctica docente fue analizada mediante software de análisis cualitativo ATLAS TI 9. Los resultados demuestran que las actividades para promover la educación para el desarrollo sostenible, incorporadas por el profesorado de ESO fomentan el cuidado del medio ambiente, centrándose especialmente en el cambio climático. Otras estaban vinculadas a aspectos sociales como, por ejemplo, la desigualdad y algunas, aunque en menor medida, en los económicos.Sin embargo, parte del profesorado no promovió la educación para el desarrollo sostenible en sus aulas. Como conclusión, se detectan prácticas didácticas que carecen de interconexión entre ellas. Por lo que se considera que el profesorado necesita formación en materia de sostenibilidad para lograr la transformación a nivel global.

The expansion of renewable energy production, especially wind power, is one of the cornerstones of our strategy for mitigating climate change. However, there is growing concern about the impacts of this energy source on biodiversity, and a need to develop tools to adequately assess this impact and mitigate its effects. In particular, very little is known about the impact on groups of fauna such as bats, which are especially sensitive to environmental changes. We investigated the temporal patterns of bat fatalities in wind farms in the province of Cádiz, in the south of the Iberian Peninsula. An eleven-year data set (2009–2019) from a surveillance program of bird and bat mortality in wind farms was analysed. A total of 2,858 fatalities concerning 10 bat genera were reported, although more than 90% of the affected animals were individuals of the genera Pipistrellus, Eptesicus and Nyctalus. Bat mortality occurred throughout the year, including all winter months in the case of the genus Pipistrellus. Nonetheless, the majority of fatalities of bats with wind turbines in the province of Cádiz occurred during summer and autumn, especially during August. The probability of mortality was positively correlated with the maximum daily temperature. According to the model prediction, the probability of fatality begins to increase slightly from 20°C and then rises sharply when the temperature exceeds 30°C. According to the regional projections of global climate models, an increase in maximum temperatures and the arrival of milder winters may lead to an increase in the annual mortality of bats in wind farms in the coming decades.

Este trabajo presenta los primeros resultados de una investigación que busca comprender cómo los líderes escolares “crean sentido” durante la fase inicial de una reforma a gran escala que ha comenzado a implementarse en Chile, conocida como “Nueva Educación Pública” (NEP). Se realizaron entrevistas semiestructuradas a doce directores de escuelas que participan en esta reforma. Los resultados arrojan que existe una amplia diversidad de significados asociados a la NEP, que pueden clasificarse en tres principales (“cambio de paradigma”, “cambio pedagógico” y “cambio burocrático”). La indagación permitió adicionalmente identificar algunos factores asociados al significado que los líderes asignan a la Nueva Educación Pública, así como describir las primeras consecuencias que tiene este proceso de “sense-making” en la implementación de esta reforma a nivel de las escuelas. Se discuten algunas implicancias para el diseño e implementación de reformas a gran escala., This paper presents the first results of a research that seeks to understand how school leaders "make sense" during the initial phase of a large-scale reform that has begun to be implemented in Chile, known as "New Public Education" (NPE). Semi-structured interviews were conducted with twelve school principals participating in this reform. The results show that there is a wide diversity of meanings associated with the NEP, which can be classified into three main ones ("paradigm change", "pedagogical change" and "bureaucratic change"). The research also made it possible to identify some factors associated with the meaning that leaders assign to the New Public Education, as well as to describe the first consequences of this "sense-making" process in the implementation of this reform at the school level. Some implications for the design and implementation of large-scale reforms are discussed.

AIMSTo study the vision related quality of life (VRQoL) before and after a mass cataract surgery campaign in a low-income country and to describe the impact of cataract surgery on quality of life (QOL). METHODSAll the patients who had cataract surgery in Bobo-Dioulasso (Burkina Faso) during a campaign for the prevention blindness were examined. VRQoL was assessed using a modified version of the WHO/PBD VF20. The questionnaire was carried out before and three months after the surgery. A QOL related to vision index (QOL-RVI) was calculated from the scores obtained.RESULTSA total of 305 patients (56.1% male) underwent cataract extraction. Mean age was 61.97 ± 14.39 years. The majority of eyes (88.70%) had preoperatively poor visual acuity (CDVACONCLUSIONSCataract surgery increases the quality of life of patients living in low-income countries such as Burkina Faso and the improvement correlates with the recovery of the visual acuity.

Sparse structures are frequently sought when pursuing tractability in optimization problems. They are exploited from both theoretical and computational perspectives to handle complex problems that become manageable when sparsity is present. An example of this type of structure is given by treewidth: a graph theoretical parameter that measures how “tree-like” a graph is. This parameter has been used for decades for analyzing the complexity of various optimization problems and for obtaining tractable algorithms for problems where this parameter is bounded. The goal of this work is to contribute to the understanding of the limits of the treewidth-based tractability in optimization. Our results are as follows. First, we prove that, in a certain sense, the already known positive results on extension complexity based on low treewidth are the best possible. Secondly, under mild assumptions, we prove that treewidth is the only graph-theoretical parameter that yields tractability for a wide class of optimization problems, a fact well known in Graphical Models in Machine Learning and in Constraint Satisfaction Problems, which here we extend to an approximation setting in Optimization.

Production scheduling is a large-scale optimization problem that must be solved on a yearly basis by every open pit mining project throughout the world. Surprisingly, however, this problem has only recently started to receive much attention from the operations research community. In this article, O. Rivera, D. Espinoza, M. Goycoolea, E. Moreno, and G. Muñoz propose an integer programming methodology for tackling this problem that combines new classes of preprocessing schemes, cutting planes, heuristics, and branching mechanisms. This methodology is shown to compute near-optimal solutions on a number of real-world planning problems whose complexity is beyond the capabilities of preexisting approaches.

Quantifying factors that influence marine predator distributions is essential to understanding the current and future change in marine biodiversity. Here, we test whether marine predator distribution relates to prey, or is better predicted by other specific habitat features. We examine the correlation between spatial distribution of three seabird species and their prey, as well as environmental proxies (oceanographic characteristics) in the Gulf of Cadiz, NE Atlantic. We modeled the at-sea distribution of Cory's shearwater, Balearic shearwater and Northern gannet, based on: (i) pelagic fish abundance according to acoustic surveys, and (ii) a forecast-model of remotely sensed environmental variables (productivity, sea surface temperature, and salinity). In general, seabird distributions were better predicted by abundance of fish than by environmental variables at the habitat scale. We obtained consistent correlations between seabird presence and the abundance of medium-sized (- cm) sardines, anchovies and Mediterranean horse mackerel, providing information on their preferred prey. Additionally, oceanographic productivity variables moderately contributed to seabird distribution models, with better predictive value for the critically endangered Balearic shearwater and Northern gannet in the summer, whilst the model for Cory's shearwater's produced poorer predictions. Predator-prey combined studies may represent essential tools for an efficient ecosystem-based management of marine environments., SI

La heparina no fraccionada (HNF) es el anticoagulante de mayor uso en pacientes hospitalizados. El rango terapéutico (RT) se definió en adultos en relación a la prolongación del Tiempo de Tromboplastina Parcial activado (TTPa). Sin embargo, la recomendación es mantener un rango terapéutico con anti factor X activado (antiFXa). Como esta técnica es más compleja de realizar y menos disponible, se recomienda hacer curvas locales de correlación de TTPa con AntiFXa. Objetivo: determinar la correlación entre los valores de TTPa y AntiFXa, en pacientes en tratamiento con HNF. Pacientes y Método: Se reclutaron 52 pacientes entre 2 días y 14 años de edad hospitalizados en Unidad de Paciente Crítico Pediátrico. Recibieron tratamiento con HNF en infusión continua por al menos 24 horas. Se tomaron muestras de TTPa y AntiFXa de acuerdo al momento de anticoagulación. Para evaluar la concordancia de los niveles de TTPa con los de AntiFXa, se utilizó el coeficiente estadístico Kappa de Landis y Koch. Resultados: se obtuvieron 105 muestras de 52 pacientes. La concordancia general fue 0,452 (correlación moderada). En los pacientes < 1 mes (n = 40), se evidenció una correlación considerable (r = 0,617), edades 1 mes a < 6 meses (n = 18), y 6 meses - < 12 meses con TTPa < 120 segundos (n = 11), mostraron igualmente una correlación considerable (r = 0,636 y 0,615 respectivamente), en tanto que en > 12 meses (n = 37) con TTPa < 120 segundos, se evidenció una correlación moderada (r = 0,454). Conclusión: En nuestra población existe una correlación moderada entre los valores de TTPa y AntiFXa.

Este artículo tiene por objetivo comparar las opiniones de directores y directoras de centros educativos públicos y privados subvencionados sobre temas relevantes de política educativa, durante un periodo (2014-2018), en el que se pusieron en marcha importantes reformas educacionales en Chile. En base a una encuesta de opinión anual, se realiza un análisis descriptivo orientado a indagar en las diferencias existentes entre estos directivos. La comparación entre las opiniones de ambos grupos muestran que, por una parte, los directivos comparten una cierta visión general de la educación y sus desafíos, visualizan la necesidad de mejorar la formación inicial docente, coinciden en las políticas educativas más relevantes para mejorar la calidad educativa, y aspiran a una similar carrera directiva. Por otra parte, se diferencian respecto a la necesidad de cambios estructurales en el sistema educativo, difieren en la principal iniciativa del gobierno de la presidenta Bachelet (la “ley de inclusión”), dan cuenta de una relación muy distinta con sus administradores, y plantean diferentes prioridades y políticas posibles para potenciar el desempeño de su cargo. Los resultados obtenidos muestran la complejidad de que los directivos de estos dos subsistemas puedan constituirse como un actor socio-político relevante para las políticas educacionales en Chile.

Apresentação do Dossiê "Liderança Educacional". Presentation of the "Educational Leadership" dossier. Introducción del dossier "Liderazgo Educativo"

According to Chilean design practice, walls usually have complex geometries and discontinuities in height, mainly in the first story. However, the Chilean design code, similar to many design codes, does not provide special provisions for discontinuities. This paper shows the results of an experimental and numerical study of walls with a central opening at the base. Four slender walls are constructed with the same general dimensions, but with different shapes of the opening (15% and 30% of the length, and 11% and 22% of the wall height). The specimens were tested under constant axial load, while cyclic lateral loading is applied at the top. One of the specimens presents slab elements at the base. Results indicate that lateral strength is similar in all cases; however, displacement capacity varies with opening size. All specimens with openings have less ductility, where the specimen with wider and taller opening had a reduced displacement capacity (∼30% reduction). The width of the opening was more influential than the height in the displacement capacity. Numerical analysis was done through a finite element modeling, where one of the models considered all features of the formulation and a second model considered rigid beams placed in all levels forcing the Bernoulli hypothesis (flexural model). Both models can capture strength, stiffness and displacement capacity, and therefore a flexural model can be used for boundary detailing.

Given its wide spectrum of applications, the classical problem of all-terminal network reliability evaluation remains a highly relevant problem in network design. The associated optimization problem -- to find a network with the best possible reliability under multiple constraints -- presents an even more complex challenge, which has been addressed in the scientific literature but usually under strong assumptions over failures probabilities and/or the network topology. In this work, we propose a novel reliability optimization framework for network design with failures probabilities that are independent but not necessarily identical. We leverage the linear-time evaluation procedure for network reliability in the series-parallel graphs of Satyanarayana and Wood(1985) to formulate the reliability optimization problem as a mixed-integer nonlinear optimization problem. To solve this nonconvex problem, we use classical convex envelopes of bilinear functions, introduce custom cutting planes, and propose a new family of convex envelopes for expressions that appear in the evaluation of network reliability. Furthermore, we exploit the refinements produced by spatial branch-and-bound to locally strengthen our convex relaxations. Our experiments show that, using our framework, one can efficiently obtain optimal solutions in challenging instances of this problem.

Convexification based on convex envelopes is ubiquitous in the non-linear optimization literature. Thanks to considerable efforts of the optimization community for decades, we are able to compute the convex envelopes of a considerable number of functions that appear in practice, and thus obtain tight and tractable approximations to challenging problems. We contribute to this line of work by considering a family of functions that, to the best of our knowledge, has not been considered before in the literature. We call this family ray-concave functions. We show sufficient conditions that allow us to easily compute closed-form expressions for the convex envelope of ray-concave functions over arbitrary polytopes. With these tools, we are able to provide new perspectives to previously known convex envelopes and derive a previously unknown convex envelope for a function that arises in probability contexts.

Objective. The aim of this research was to compare three cephalometric analyses and their correlation with the airway volume in subjects with different skeletal classes using 2D and 3D images. Study Design. Cross-sectional descriptive study. Material and Method. Steiner, McNamara, and Ricketts analyses and the airway volume were compared in 115 subjects who were candidates for orthognathic surgery under diagnosis using cone beam computed tomography (CBCT); 46 males (40%) and 69 females (60%) were included. The sagittal positions of the maxilla and mandible, the angulation of the mandibular plane, the sagittal positions of the upper and lower incisors, measurements of the largest or shortest airway area, and the volume were compared using Spearman’s test considering a p value p = 0.01 ). For mandibular angulation, there was a greater difference between values for Steiner and Ricketts techniques ( p = 0.001 ). In the upper incisor, the results for McNamara and Ricketts techniques were significantly different ( p = 0.004 ). Analysing the airway, subjects with a class II skeletal pattern had a smaller volume than those with a class III pattern ( p = 0.034 ). Conclusion. It may be concluded that skeletal class II patients have a significantly smaller airway volume than class III patients. The skeletal parameter does not always relate to the airway volume; however, the high mandibular angle could be related to the airway conditions.

The aim of this study was to develop a Preventive Oral Health Exam for Elderly People (EDePAM), using the e-Delphi technique, to diagnose oral health problems in people 65 or older. The e-Delphi technique was used with experts in multiple stages, and in a final workshop, where an agreement on an examination protocol was reached for diagnosing dental caries, oral mucosa lesions, periodontal diseases, and masticatory function disorders. Quantitative analyses of all the rounds of the e-Delphi method were conducted. It was agreed that the International Caries Detection and Assessment System (ICDAS) should be used together with a modified version of the Nyvad criteria to detect and assess caries lesions. It was also agreed that an assessment was needed of the different factors involved in determining caries risk, namely socioeconomic level, access to fluoride, level of dependence/functionality, salivary flow, history of head and neck cancer treatment, use of medications that decrease salivary flow, diet, use of removable dental prostheses, exposure of root surfaces, and caries history. Furthermore, patients would be required to undergo an examination of the oral mucosa, where any existing lesion should be described in terms of its clinical appearance, location, and risk potential. It was also agreed that an assessment of masticatory function should be performed using the Leake index, together with chewing-gum combined with a color scale to categorize masticatory performance. The number of pairs of occluding antagonist teeth was considered as the best predictor of masticatory function. The 2018 classification by the American Academy of Periodontology (AAP) / European Federation of Periodontology (EFP) was accepted as the standard to assess periodontal status, and it was agreed that this assessment should include an evaluation of clinical attachment loss and bleeding on probing. The novel EDePAM was considered as appropriate for conducting a functional assessment of oral health by providing a comprehensive diagnosis of oral diseases.

Due to both theoretical and practical considerations, relaxations of MINLPs are usually required to be convex. Nonetheless, current optimization solvers can often successfully handle a moderate presence of nonconvexities, which opens the door for the use of potentially tighter nonconvex relaxations. In this work, we exploit this fact and make use of a nonconvex relaxation obtained via aggregation of constraints: a surrogate relaxation. These relaxations were actively studied for linear integer programs in the 70s and 80s, but they have been scarcely considered since. We revisit these relaxations in an MINLP setting and show the computational benefits and challenges they can have. Additionally, we study a generalization of such relaxation that allows for multiple aggregations simultaneously and present the first algorithm that is capable of computing the best set of aggregations. We propose a multitude of computational enhancements for improving its practical performance and evaluate the algorithm’s ability to generate strong dual bounds through extensive computational experiments.

Título, resumen y palabras clave en español e inglés Resumen basado en el de la publicación Se definen competencias básicas profesionales que acrediten a los educadores sociales como agentes de sostenibilidad. Después de contextualizar la sostenibilidad, ésta se presenta como una competencia necesaria y global en Educación Superior. Posteriormente, a partir de una metodología socio-cualitativa de corte descriptivo, se identifican carencias en los planes de estudio del grado de Educación Social en lo referente a la sostenibilidad y la inclusión de los objetivos de desarrollo sostenible. Se muestra la necesidad de actualizar la formación del educador social con un currículum propositivo de 16 nuevas competencias formativas de carácter profesionalizante. ESP

The intersection cut paradigm is a powerful framework that facilitates the generation of valid linear inequalities, or cutting planes, for a potentially complex set S. The key ingredients in this construction are a simplicial conic relaxation of S and an S-free set: a convex zone whose interior does not intersect S. Ideally, such S-free set would be maximal inclusion-wise, as it would generate a deeper cutting plane. However, maximality can be a challenging goal in general. In this work, we show how to construct maximal S-free sets when S is defined as a general quadratic inequality. Our maximal S-free sets are such that efficient separation of a vertex in LP-based approaches to quadratically constrained problems is guaranteed. To the best of our knowledge, this work is the first to provide maximal quadratic-free sets.

En la última década, en Chile se ha puesto en marcha una serie de políticas destinadas a fomentar el liderazgo educativo. Sin embargo, poco se sabe acerca de las características de la investigación que se ha realizado en esta temática. Esta revisión topográfica analiza de manera sistemática los artículos en torno al liderazgo educativo en Chile, que cuentan con una base de investigación empírica y que fueron publicados en revistas indexadas en el período comprendido entre 2008 y 2019. Los resultados muestran que se han publicado 47 artículos, con un aumento sustantivo desde el año 2016 en adelante. Dichos artículos han sido publicados por un grupo de 85 autores, no obstante, la mayoría de ellos solo ha publicado un artículo. Las investigaciones se caracterizan por ser mayoritariamente descriptivas y cualitativas, siendo escasas las que han realizado muestreo de tipo aleatorio o que han explotado los datos secundarios existentes. Un 40% de los artículos declara no haber contado con recursos para desarrollar su investigación. Los focos de investigación más estudiados han sido los directores, así como las escuelas municipales. Las publicaciones se han concentrado en revistas latinoamericanas e indexadas en Scopus. La caracterización realizada permite considerar al campo de estudio como emergente, sugiriéndose un conjunto de medidas que permitirían su consolidación.

Los directivos escolares suelen ser reivindicados en tanto ejecutores de políticas educativas, reconociéndoseles un rol clave para su éxito o fracaso en las escuelas que lideran. Este artículo analiza, a partir de encuestas anuales comparables, la opinión que los directores de centros educativos tuvieron respecto de las políticas educativas desarrolladas en Chile bajo el reformista gobierno de la presidenta Michelle Bachelet (2014-2017). Los resultados dan cuenta que la iniciativa que más marcó la opinión de los directivos fue la ley de inclusión educativa, aprobada de manera controversial a inicios del período. En torno a ella se produjo un mayor pesimismo inicial respecto del futuro de la educación nacional, así como se tendió a distanciar la opinión de los directivos que trabajan en el sector público respecto del privado. Igualmente puede apreciarse que la opinión de los directivos es dinámica, modificándose en el transcurso del gobierno, que aquella suele manifestar la urgencia de ciertas políticas educativas (como la mejora de la formación inicial docente) por sobre el resto y que también brinda valiosa información sobre los efectos de las políticas en los centros educativos mismos. Por ello, dada su calidad de informantes cualificados, los tomadores de decisión debiesen considerar sistemáticamente sus opiniones en el diseño e implementación de las políticas, School managers are often vindicated as executors of educational policies, recognizing a key role for their success or failure in the schools they lead. This article analyzes, from comparable annual surveys, the opinion that the directors of educational centers had regarding the educational policies developed in Chile under the reformist government of President Michelle Bachelet (2014-2017). The results show that the initiative that most marked the opinion of the directors was the law of educational inclusion, approved controversially at the beginning of the period. Around it there was greater initial pessimism regarding the future of national education, as well as a tendency to distance the opinion of managers working in the public sector with respect to the private sector. It can also be seen that the opinion of managers is dynamic, changing in the course of the government, which usually manifests the urgency of certain educational policies (such as improving initial teacher training) above the rest and also provides valuable information on the effects of policies in the educational centers themselves. Therefore, given their quality as qualified informants, decision makers should systematically consider their opinions in the design and implementation of policies

SUMMARY: It is critical to know the precise location and configuration of the mandibular canal (MC) to avoid damages in the alveolar inferior nerve during an invasive dental treatment. The aim of this study was to provide anatomic relationships of the mandibular canal in its entire pathway related to cortical walls and dental roots to serve as basic knowledge for dental clinical procedures performed in this area. We analyzed 50 CBCT images assessing the specific location of MC at the retromolar space as related to inferior teeth roots. Data were analyzed by side using descriptive statistics (median: mean [M], standard deviation [SD], 95 % confidence interval: lower endpoint [IC] and upper endpoint [IC’]). The MC length and pathway were measured from the mandibular foramen up to the mental foramen. MC was closer from lingual cortical than buccal at the retromolar space as well the distal root of the second molar and the root of the second premolar are closest to MC. A mean length for the MC of 70.8 (±5.3 mm) for the right side and 71 (±5.8 mm) for the left side were observed. In conclusion, it is critical for clinicians to know three-dimensionally the topographic relationships between the inferior teeth roots and the mandibular canal before proceeding to any invasive dental or surgical procedure at this region.

Las organizaciones de usuarios de aguas se entienden organizadas o formadas, segun la normativa vigente, solo cuando son registradas por la Direccion General de Aguas; tramite que es igualmente necesario cumplir cuando se modifican sus estatutos. Asimismo, el citado registro debe efectuarse ya sea cuando la O. U. se ha organizado o formado convencionalmente; o bien, cuando lo ha sido judicialmente. Sin embargo, en este ultimo caso, especialmente si en el respectivo procedimiento judicial ha existido controversia entre dos o mas de los interesados, el referido registro plantea algunos inconvenientes de caracter practico y otros de caracter juridico, sobre los cuales se ocupa el presente trabajo; y cuya solucion propondre, al finalizar, una solucion de caracter transitorio y otras de caracter definitivo.

We study a Lagrangian decomposition algorithm recently proposed by Dan Bienstock and Mark Zuckerberg for solving the LP relaxation of a class of open pit mine project scheduling problems. In this study we show that the Bienstock---Zuckerberg (BZ) algorithm can be used to solve LP relaxations corresponding to a much broader class of scheduling problems, including the well-known Resource Constrained Project Scheduling Problem (RCPSP), and multi-modal variants of the RCPSP that consider batch processing of jobs. We present a new, intuitive proof of correctness for the BZ algorithm that works by casting the BZ algorithm as a column generation algorithm. This analysis allows us to draw parallels with the well-known Dantzig---Wolfe decomposition (DW) algorithm. We discuss practical computational techniques for speeding up the performance of the BZ and DW algorithms on project scheduling problems. Finally, we present computational experiments independently testing the effectiveness of the BZ and DW algorithms on different sets of publicly available test instances. Our computational experiments confirm that the BZ algorithm significantly outperforms the DW algorithm for the problems considered. Our computational experiments also show that the proposed speed-up techniques can have a significant impact on the solve time. We provide some insights on what might be explaining this significant difference in performance.