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A comienzos del siglo XVII, se presentaron unos conflictos al interior de las encomiendas de Susa y Turmequé, al nororiente de la Audiencia de Santafé. En el desarrollo de esos hechos estuvo presente un agente en común: el cura doctrinero Pedro de Zea. Este hombre se enfrentó a los propietarios de esas encomiendas (Isabel Ruiz y la Corona), ya que ellos denunciaron sus comportamientos y su inconstancia con la evangelización. Sin embargo, más allá de las denuncias que ambos agentes manifestaron, ellos exhibieron sus deseos, ilusiones e intereses personales; es decir, sus pasiones. En este escrito se describirá el “itinerario de vida” del presbítero Pedro de Zea, su paso por diferentes encomiendas de las provincias de Tunja y Santafé, entre 1600 y 1627, enfatizando en las tensiones que tuvo con diferentes encomenderos, y las pasiones que estos hechos originaron en los protagonistas y su incidencia en la cotidianidad de aquellas unidades político territoriales. Es una forma de comprender que más allá de los procesos políticos, económicos, sociales y culturales que se presentaron en el periodo colonial, había hombres y mujeres con unos complejos e intrincados mundos internos.

El Peru se ha caracterizado en los ultimos anos por atravesar una profunda crisis politica y juridica ocasionada, en buena parte, por las tensiones existentes entre los poderes Ejecutivo y Legislativo. En concreto, la causal de vacancia por incapacidad moral permanente ha sido utilizada de forma frecuente en los ultimos anos, lo que ha despertado un singular interes por delimitarla juridicamente. Bajo este tenor, el presente articulo estudiara cual es la delimitacion conceptual de la vacancia presidencial por incapacidad moral permanente que se ha esbozado desde la doctrina y, en tal sentido, enfatizara si efectivamente existe una necesidad de adoptar una delimitacion a nivel juridico que contribuya a la estabilidad democratica y la gobernabilidad.

Islands are key areas for biodiversity; however, they are extremely sensitive to anthropic actions. This has led to local species extinctions, especially large predators such as raptors. Consequently, reintroduction and conservation projects aimed at reversing population decline of endangered species have recently gained popularity. Nevertheless, their relatively elevated cost and chance of failure make them controversial, hence assessing their effectiveness is essential. Within the early stages of raptors, the post-fledging dependency period (PFDP) is the one in which individuals must face dangers without having completely developed their skills. Thereby, comparing PFDP patterns concerning reintroduced and wild individuals is of major interest as it would help to plan and improve future conservation actions. We analyzed the behavior of 38 juvenile Bonelli’s eagles (15 reintroduced and 23 wild) tracked through GPS telemetry, tagged as nestlings in two insular environments. The study period encompassed a total of nine-year movement data from reintroduced chicks in Mallorca (Spain) and wild chicks from Sicily (Italy). Movement parameters (i.e., age of first flight, age of dispersal, length of the PFDP, revisits to the natal or release area, and residence time in them) were analyzed together with their behavior during the PFDP for reintroduced and wild individuals. Similar movement patterns were obtained for both origins, although wild individuals revisited the natal site more often and dispersed earlier. Behavior was also similar, it varied throughout the PFDP, observing a more abrupt progress in wild individuals and an earlier development of travelling and hunting behaviors. Observed differences are probably related to food availability, which can improve body condition and thus delay onset of dispersal, together with parental presence, which can prompt an earlier ending of the PFDP by encouraging juvenile independence.

espanolResena del libro: Langebaek, Carl Henrik. Los muiscas. La historia milenaria de un pueblo chibcha. Bogota: Editorial Debate, 2019, 309 pp. EnglishReview of the book entitled: Langebaek, Carl Henrik. Los muiscas. La historia milenaria de un pueblo chibcha. Bogota: Editorial Debate, 2019, 309 pp.

Introduction: colorectal cancer is the third most frequently type of cancer diagnosed, both men and women; adequate and timely research is required to decrease morbidity and mortality rates from this type of cancer. Objective: to carry out research work of colorectal diseases in patients from 45 years old and older belonging to No- 18 Medical Office at Raúl Sánchez Polyclinic, in 2017. Methods: an observational, descriptive and cross-sectional study was conducted; the target group comprised 29 positive patients into the research, working with the totality of them. Theoretical, empirical and statistical percentage methods were applied; data were taken to tables for better understanding. Results: 15.05% of the population over 45 years old was positive in the study conducted into the research, where 58.97% belonged to male sex, out of them 35.90% were over 65 years old, and 53.85% had family history of colorectal diseases; 56.41% of the patients were overweight or obese; 76.92% presented smoking as a risk factor and it was found that 89.74% consumed high amounts of animal fat, 58.97% of the them were asymptomatic; while 30.77% presented colic or abdominal pain as symptoms. Conclusions: male patients over 65 years were susceptible to the development of colorectal diseases, where poor eating habits, obesity and smoking represented the major risk factors for the development of this disease.

El Modelo de la Conservación de los Recursos sirve de sustento teórico a muchas de las investigaciones sobre el estrés que desde hace algunos años se realizan a nivel internacional. Nuestro propósito es delinear, a partir de la bibliografía revisada, sus principios, corolarios y conceptos fundamentales, como los de “caravana”, “pasadizo” y “cruce de recursos”. También se aborda la relación de este modelo con el Síndrome de Desgaste Profesional y con el constructo “estrés percibido”. Se concluye que la capacidad del modelo para sustentar una amplia gama de hipótesis en el campo de la investigación sobre el estrés y su utilidad para la intervención clínica en individuos y grupos, y para el diseño de programas de intervención en comunidades bajo circunstancias de déficit o de pérdida de recursos, lo hace un importante referente teórico para la actividad práctica e investigativa en el contexto cubano.

1. Long‐distance migrations are among the most physically demanding feats animals perform. Understanding the potential costs and benefits of such behaviour is a fundamental question in ecology and evolution. A hypothetical cost of migration should be outweighed by higher productivity and/or higher annual survival, but few studies on migratory species have been able to directly quantify patterns of survival throughout the full annual cycle and across the majority of a species’ range. 2. Here, we use telemetry data from 220 migratory Egyptian vultures Neophron percnopterus, tracked for 3,186 bird months and across approximately 70% of the species’ global distribution, to test for differences in survival throughout the annual cycle. 3. We estimated monthly survival probability relative to migration and latitude using a multi‐event capture–recapture model in a Bayesian framework that accounted for age, origin, subpopulation and the uncertainty of classifying fates from tracking data. 4. We found lower survival during migration compared to stationary periods (β = −0.816; 95% credible interval: −1.290 to −0.318) and higher survival on non‐breeding grounds at southern latitudes (

Phylogenetics deals with the task of reconstructing all the ancestral relations among a set of lineages. For any given phylogenetic tree that explains their evolution, subject to the Kimura Three Parameters Model, Hadamard Conjugation is an equation that relates its tree weights (within a matrix Q) to its substitution patterns distribution (within a matrix P) on leaves. In practice, the latter matrix is approximated via the DNA sequence alignment. Some challenges have to be faced in the process such as filling the gaps when they exist. Throughout this manuscript, it is provided fully explanation of how the matrix P can be approximated. The authors contribute to the scientific community with one library running on Maple to lead with these tasks. We conclude this work with a fully developed example focused on three spieces of orchids of the genus Lophiarella distributed in southwestern Mexico and northwestern Mesoamerica for which we obtained the matrix P.

Knowledge discovery from databases is a very attractive and challenging task. The elicitation of fuzzy predicates (called FuzzyPred) in conjunctive and disjunctive normal form provides a convenient and effective general way to identify and to represent certain dependencies among items in fuzzy transactions. Konstanz Information Miner (KNIME) is a strong and comprehensive free platform for drag-and-drop analytics, machine learning, statistics, and data processing. It already offers a large variety of nodes, which enables easy execution of data pipelines. This paper presents a new plug-in that integrates FuzzyPred into KNIME. It allows reducing the amount of knowledge and experience required by users to use the method. A case of study is given to illustrate the use of the proposal.

Diclofenac is a non-steroidal anti-inflammatory drug (NSAID) with a well-known toxicity for old world vultures that ingest the carrion of domestic animals treated with it. Diclofenac intoxication was directly related to the dramatic declines in the populations of three native South Asian Gyps vulture species two decades ago. In 2013, this NSAID was authorised for veterinary use in Spain, which has the largest vulture populations in Europe. One of these species is the cinereous vulture (Aegypius monachus), which is classified as “near threatened” by the International Union for Conservation of Nature (IUCN). This species has been reintroduced and monitored in Catalonia (NE Spain) since 2007, and in 2020 its current population consisted of 15 breeding pairs and a total number of 61 individuals. In September 2020, one fledgling was found dead in the nest. Post-mortem examination revealed severe generalised visceral and articular gout, which was confirmed histologically. Diclofenac was detected at average concentrations of 26.5 ng/g in the liver and 51.4 ng/g in kidney replicates (n = 3), respectively. These findings support a diagnosis of fatal gout caused by diclofenac intoxication. This is the first case of diclofenac poisoning in Spain (and in Europe), in addition to being the first report of diclofenac poisoning in cinereous vultures. This case report, therefore, supports the need to closely monitor vulture populations and carry out strict regulatory measures with which to prevent these poisonings., The programme to reintroduce the cinereous vulture into the Catalan pre-Pyrenees has been funded by “Obra Social la Caixa” (through a contract with the “Generalitat de Catalunya”), the “Red Eléctrica de España” and the “Fundación Biodiversidad” from the Spanish Ministry of Ecological Transition and Demographic Challenge (MITECO).

Evolutionary algorithms (EAs) have been with us for several decades and are highly popular given that they have proved competitive in the face of challenging problems’ features such as deceptiveness, multiple local optima, among other characteristics. However, it is necessary to define multiple hyper-parameter values to have a working EA, which is a drawback for many practitioners. In the case of genetic programming (GP), an EA for the evolution of models and programs, hyper-parameter optimization has been extensively studied only recently. This work builds on recent findings and explores the hyper-parameter space of a specific GP system called neat-GP that controls model size. This is conducted using two large sets of symbolic regression benchmark problems to evaluate system performance, while hyper-parameter optimization is carried out using three variants of the iterated F-Race algorithm, for the first time applied to GP. From all the automatic parametrizations produced by optimization process, several findings are drawn. Automatic parametrizations do not outperform the manual configuration in many cases, and overall, the differences are not substantial in terms of testing error. Moreover, finding parametrizations that produce highly accurate models that are also compact is not trivially done, at least if the hyper-parameter optimization process (F-Race) is only guided by predictive error. This work is intended to foster more research and scrutiny of hyper-parameters in EAs, in general, and GP, in particular.

This work presents a new method for assisting in the identifcation process of missing persons in several contexts, such as enforced disappearances. We apply a Bayesian technique to incorporate non-genetic variables in the construction of prior information. In that way, we can learn from the already-solved cases of a particular mass event of death, and use that information to guide the search among remaining victims. This paper describes a particular application to the proposed method to the identifcation of human remains of the so-called disappeared during the last dictatorship in Argentina, which lasted from 1976 until 1983. Potential applications of the techniques presented hereby, however, are much wider. The central idea of our work is to take advantage of the already-solved cases within a certain event to use the gathered knowledge to assist in the investigation process, enabling the construction of prioritized rankings of victims that could correspond to each certain unidentifed human remains., Facultad de Ingeniería

Introduction: diabetes mellitus is considered one of the epidemics of the century, associated with inadequate lifestyles. Objective: to describe the risk factors related to nutrition and the nutritional status of patients with diabetes mellitus attended at the Hermanos Cruz polyclinic during 2017. Method: an observational, descriptive cross-sectional study was conducted between July and December 2017 at Hermanos Cruz polyclinic. From a target group of 1782 older adults with diabetes mellitus, a sample of 123 was randomly selected. A survey was applied, giving nutritional and food counseling, assessing anthropometry data, and the evaluation of eating habits and blood glucose measurement were performed. Data processing was carried out with the SPSS software package version 21.0. Medical ethics approaches were respected. Results: the average age was 65 years, women predominated (61,0 %); 89,4 % had not received counseling by a nutritionist, while 63,4 % had malnutrition due to excess. High carbohydrate intake (90,2 %), daily consumption of protein sources of high biological value (67,5 %), and the habit of sweetening with sugar (96,7 %) predominated in eating habits. The blood glucose values behaved over the recommended limits. Conclusions: there was a high prevalence of nutrition and nutritional risk factors in the sample studied, which resulted in the differentiated awareness that must be assumed with the Nutritional Counseling, taking into consideration that the causes mentioned above are a cause of complications in diabetic patients.

En el desarrollo del presente articulo, se analiza la posicion institucional del Congreso de la Republica en el sistema constitucional peruano. Para ello, se explica en que consiste el principio de democracia representativa y sus caracteristicas principales en los sistemas de representacion “unicameral” y “bicameral” del Congreso de la Republica. Posteriormente, se analizan los proyectos de ley que proponen restituir el sistema bicameral en el Congreso actual y se exponen los posibles efectos juridicos y politicos que podria causar su retorno en la politica peruana actual.

Drug is a general term that designates any substance with the capacity to alter a biological or chemical process in a living organism, with a determined purpose such as fighting a disease, increasing physical resistance or modifying the immune response. The research was carried out with the objective of describing drugs, their behavior in the world and their prevention; to conduct this research 20 literature references were searched. Drugs constitute a global health problem that affects the population, and it is fought with preventive actions by working teams and community participation in order to achieve a satisfactory health status.

Introduction: atherosclerosis is one of the great predators of human health; diabetes mellitus and aging are considered among its causes, which have become an important health problem. Objective: to identify the main risk factors of atherosclerosis in old people with type 2 diabetes mellitus in a medical office. Method: an observational, descriptive and cross-sectional study was carried out in the medical office No.16 at Hermanos Cruz Polyclinic in Pinar del Rio municipality and province, during December 2015 and February 2016. A target group of 77 old people with the diagnosis of diabetes mellitus type 2 was studied. All the old people under study applied a survey arranged by the authors. Descriptive statistics were used and the principles of medical ethics were met. Results: female sex was the most affected, hypertension 71,4 % was the prevailing risk factor in both sexes, the combination of most frequent risk factors were hypertension-obesity in 19,5 %, the consequent diseases of atherosclerosis turned out to be ischemic heart disease in 18,2 %, and in 16,4 % peripheral venous insufficiency. Conclusions: a high prevalence of risk factors for atherosclerosis and hypertension is the most frequent. Differentiated care has to be assumed in the presence of hypertension-obesity, due to its high association with the arteriosclerotic causes studied.

Resumen El concepto de problema matemático constituye una categoría central para la didáctica de la matemática. Su definición ha sido interés de diversos autores, aunque aún es un aspecto polémico dentro del quehacer investigativo de los especialistas. En las referidas definiciones se aprecia un mayor énfasis en los rasgos estructurales externos de los problemas, lo que ha generado que las mismas tengan un marcado carácter descriptivo en detrimento de su función explicativa. La situación descripta afecta la comprensión de la esencia de dicho objeto de estudio y por tanto la dirección de su proceso de enseñanza-aprendizaje. Por lo anteriormente expuesto en el artículo se persigue el objetivo de reflexionar sobre el concepto de problema matemático. El empleo de métodos teóricos, tales como: el analítico – sintético, el inductivo – deductivo y el histórico–lógico permitieron develar las tendencias predominantes en la definición del concepto objeto de estudio y realizar una redefinición del mismo. Abstract The concept of mathematical problem constitutes a central category for the Didactics of the Mathematical one. To grief that the same one has been defined by diverse authors, not yet consensus among them exists. In the referred definitions each author has emphasized in particular elements, which has generated that the same ones have a noticeable descriptive character. The situation deciphers affects the understanding of the essence of this object of study and therefore the direction of its process of teaching - learning. By previously exposed in the article the objective is persecuted to reflect about the concept of mathematical problem. The use of theoretical methods, such as: analytical – the synthetic one, inductive – deductive and historical – logical one allowed to reveal the predominant tendencies in the definition of the concept study object and to make a redefinition of the same one. &nbsp

In the additive hazards model the hazard function of a survival variable T is modeled additively as , where λ0(t) is a common non parametric baseline hazard function and is a vector of independent variables. For this model, the pioneering work of Lin and Ying (1994) develops a closed-form estimator for the regression parameter from a new estimating equation. That equation has a similar structure to the corresponding partial likelihood score function for the multiplicative model (Cox 1972) in that it exploits a martingale structure and it allows estimation of separate from the baseline hazard function. Their estimator is asymptotically normal and highly efficient. However, a potential drawback is that it is very sensitive to outliers. In this paper we propose a family of robust alternatives for estimation of the parameter in the additive hazards model which is robust to outliers and still highly efficient and asymptotically normal. We prove Fisher-consistency, obtain the influence function, and ill...

We analyses the main causes of landslides in the Tijuana metropolitan area (Baja California, Mexico) and discuss the conditioning and triggering factors affecting land instability in the region. The case of a landslide occurred in a neighbourhood of the city, which affected several buildings, and study to investigate its causes is presented. The study included the analysis of static and dynamic stability and the calculation of safety factors. Analysis of the causes of land instability in the region and this particular case study enabled us to draw conclusions regarding the natural and anthropic factors with the greatest bearing on landslides occurring in the city and to make recommendations for non-structural actions and measures aimed at reducing the risk of damage to the land and buildings.

Este trabajo fue realizado con el objetivo de evaluar el efecto de la inclusión de Bore (Alocasia macrorhyza) en la ración de cerdos en las fases de levante y ceba sobre el consumo de alimento, ganancia diaria de peso y conversión alimenticia. El estudio se realizó en el Municipio de Granada (Meta), con 24 cerdos de raza Pietrain, distribuidos en 4 tratamientos de dos cerdos cada uno, con tres repeticiones. Los tratamientos fueron: Tratamiento testigo, el cual corresponde a un núcleo comercial con aceite de palma, CT; bore a voluntad + núcleo proteico de 46.9% proteína bruta, NPB; bore a voluntad + núcleo proteico + 0.1 kg de aceite de palma, NPB-AP100; bore, a voluntad + núcleo proteico + 0.2 kg de aceite de palma NPB-AP200. Los niveles de bore influyeron significativamente (P

The efficient excavatability of ground is an issue that has still to be fully resolved. Although many existing criteria currently address this problem, they do not coincide with respect to the question whether mechanical methods are better than drilling and blasting for a specific type of ground. This is undoubtedly due to the variety of parameters involved. In the present study, ground in which a cut was to be made was chosen in order to compare the different existing criteria, highlighting the differences between them. To carry out this study, numerous laboratory and field trials were conducted, including the performing of mechanical tests to select the optimum method for excavating the ground in the area under study.

La pesquería de la almeja chocolata Megapitaria squalida es una actividad que no ha quedado exenta de la captura inmoderada, ya que su pesca que no presenta ningún tipo de restricción. Además, esta almeja es un importante recurso pesquero para el Estado de Sinaloa, por lo que es prioritario proponer recomendaciones para su conservación y manejo sustentable. El objetivo de esta investigación es evaluar el efecto de los parámetros ambientales en las respuestas metabólicas de organismos cultivados, y las respuestas reproductivas de una población silvestre de M. squalida. Se realizaron recolectas de organismos desde junio 2013 a junio 2014. Para el grupo de bivalvos cultivados, el experimento mostró estar negativamente correlacionado con la temperatura (r= -0.53), salinidad (r= -0.75), pH (r= -0.73), SST (r= -0.49), pero de manera positiva co las concentraciones de la Cla (r= 0.44) y MOP (r= 0.59), con el crecimiento. En los primeros meses de cultivo se observó una tendencia en el almacenamiento de nutrientes, posteriormente, se registró una disminución en los mismos, lo cual coincide con la etapa de mayor crecimiento de los animales. La longitud y peso inicial de la almeja fueron de 5.74 mm y 0.05 g, respectivamente. Después de un año de cultivo los animales alcanzaron 52.99 mm de longitud y 39.97 g de peso, obteniendo una tasa de crecimiento especifico de 4.47 mm/mes, mientras que el índice de condición de Fulton fluctuó entre 0.004 y 0.006. La proporción sexual (hembra:macho) de la población silvestre de M. squalida en Bahía Altata, Navolato, no mostró diferencias significativas (1.08:1; p

The behaviour of different gases (He, N 2 and CH 4 ) in coal was analyzed using a device for treating raw coal, designed for taking samples in the mine. This device was subsequently used to transport the samples and inject them with the gases under study. Experiments were conducted under different pressures, and a clear relationship was found between the drop in pressure and the occupation of different storage levels. On analysing the pressure evolution it was found that helium rapidly stabilised due to the characteristics of this gas. As for the other gases, N 2 showed a percentage fall much lower than that of CH 4 . In order to compare the storage capacity of different materials with respect to these gases, experiments were performed with different materials which form the mine's ceiling and walls. It was shown that the fall in pressure is very inferior. A fitting equation relating the evolution of pressure with time is proposed which may be used to define the time needed for the gas to stabilize in the coal. A normalized equation, very similar to that proposed by Langmuir, is likewise obtained to characterize the adsorption and desorption processes.

A general approach to Bayesian isotonic changepoint problems is developed. Such isotonic changepoint analysis includes trends and other constraint problems and it captures linear, non-smooth as well as abrupt changes. Desired marginal posterior densities are obtained using a Markov chain Monte Carlo method. The methodology is exemplified using one simulated and two real data examples, where it is shown that our proposed Bayesian approach captures the qualitative conclusion about the shape of the trend change., Departamento de Matemática

In this article, we present a new family of estimators for the regression parameter β in the Additive Hazards Model which represents a gain in robustness not only against outliers but also against unspecific contamination schemes. They are consistent and asymptotically normal and furthermore, and they have a nonzero breakdown point. In Survival Analysis, the Additive Hazards Model proposes a hazard function of the form λ (t)=λ0 (t)+β′z, where λ0(t) is a common nonparametric baseline hazard function and z is a vector of independent variables. For this model, the seminal work of Lin and Ying (1994) develops an estimator for the regression parameter β which is asymptotically normal and highly efficient. However, a potential drawback of that classical estimator is that it is very sensitive to outliers. In an attempt to gain robustness, Álvarez and Ferrarrio (2013) introduced a family of estimators for β which were still highly efficient and asymptotically normal, but they also had bounded influence functions. Those estimators, which are developed using classical Counting Processes methodology, still retain the drawback of having a zero breakdown point., Facultad de Ciencias Exactas

The aim of this study is to present a modification of the failure criteria of rock masses, separately considering the effect that the Bieniawski’s rock mass rating (RMR) has due to joints, as well as the RMR linked to compressive strength of the mass rock. This modification can be applied to three of the already existing criteria: that of Bieniawski–Yudhbir–Kalamaras, that of Sheorey, and that of Hoek–Brown, comparatively analysing the effects of the three modifications that have been proposed. The new, modified criterion will be validated with new data obtained in a marble mine exploited by means of rooms and pillars. The values observed and measured in the mine are compared to those obtained through numerical modelling of the pillars, using the Analisis Lagrangiano de Medios Continuos, Lagrangian Analysis of Continuous Media (ALMEC) program. Finally, several conclusions related to the application of these rock failure criteria to the analysis of mining excavation of rooms and pillars will be proposed.

This study presents a three-dimensional development of the n–k–g influence function with the aim of predicting subsidence phenomena and characterizing the shape and dimensions of the corresponding trough. The parameters “ n ” and “ k ” characterize the ground and “ g ” is related to the gravity. This function depends on two physical concepts: the first is gravity, which characterizes the forces acting on the ground, and the second, the convergence of the roof and floor of the mine workings due to the stress state of the ground. Caving in of the roof generates direct subsidence, and the swelling of the floor, indirect subsidence, which allow us to establish the shape of the trough. The physical concepts introduced are fundamental in the mathematical implementation of the n–k–g influence function, allowing a more intuitive interpretation of the subsidence trough and notably facilitating the work of calibration, validation and sensitivity analysis. These concepts likewise allow the scope of application of influence functions to be extended to non-horizontal seams, also taking into account the quality of the rock mass and the presence of preferential sliding directions, in both the roof and the floor of the seam. In the development of this paper, we shall first see the physical concepts considered, to then present the three-dimensional implementation of our n–k–g influence function. We shall see the results obtained when calibrating the proposed numerical model with real data obtained from subsidence measurements in a coalmine in the Coal Basin of Asturias, situated in the North of Spain.

Automatic mesh generators of 2D polygonal domains, especially those that use structured meshes, generate elements (triangles or quadrilaterals), which, in relatively complex models, tend to lose their equilateral form. In order to avoid this, the posterior smoothing of elements is necessary to obtain meshes with minimum geometrical distortions. In this paper, one of these smoothing techniques is developed for use in underground modelling. A system of equations is generated in a similar mode to structural analysis, where the degrees of freedom are the smoothed values of each node coordinate, and the local stiffness matrix is a measure of the geometrical connectivity of each element in the mesh. This facilitates the smoothing of non-convex domains with interior islands, which allows the imposition of directionally constrained nodes on the boundary of the domain. At present, this method is being utilized to compliment our mesh generation technique for the discretization of tunnels in 2D.

Roofing slate exploitations in Spain are concentrated within the regions of Valdeorras and La Cabrera. These progressively increased their production in the early sixties, and generated great volum...

In this paper we present a model which allows us to determine methane development in an underground vertical coal seam exploited by sublevel stoping method. The degassification model allows to evaluate the total quantity of methane developped in a predetermined time interval and to know the time evolution of that development considering the exploitation method sequence, so that the ventilation system design will be optimized. Elastoplastic behaviour of rock mass with material softening/hardening and the sorption/desorption kinetics of methane in coal are simultaneously considered. The gas properties are depending on plastic strain in rocks mass. The results of a validation test are compared with the experimental measures in Mina La Camocha (Gijon -Spain)

Optimal shape design is one of the branches of optimal structural design which uses as design variables aspects of the configuration of the system, its geometrical disposition and its dimensions.

En el presente trabajo analizamos como influye genéticamente una población estable de plantas Y sobre otra población X de la misma especie, ambas infinitas. Dicha influencia se explica al suponer que la población Y es portadora de gametos masculinos para la población X. Ambas poblaciones son diploides y estudiamos un solo gen con alelos A y a, de modo que los cigotos asociados son AA, Aa y aa. En consecuencia, XyY se representaron por ternas de números reales, X= (x0, x1, x2) yY= (y0, y1, y2), con coordenadas no negativas que suman 1, que a su vez indican los porcentajes de los distintos genotipos en la población.