A computer-algebraic approach to the study of the symmetry properties of molecules and clusters

This thesis work is dedicated to use the computer-algebraic approach for dealing with the group symmetries and studying the symmetry properties of molecules and clusters. The Maple package Bethe, created to extract and manipulate the group-theoretical data and to simplify some of the symmetry applications, is introduced. First of all the advantages of using Bethe to generate the group theoretical data are demonstrated. In the current version, the data of 72 frequently applied point groups can be used, together with the data for all of the corresponding double groups. The emphasize of this work is placed to the applications of this package in physics of molecules and clusters. Apart from the analysis of the spectral activity of molecules with point-group symmetry, it is demonstrated how Bethe can be used to understand the field splitting in crystals or to construct the corresponding wave functions. Several examples are worked out to display (some of) the present features of the Bethe program. While we cannot show all the details explicitly, these examples certainly demonstrate the great potential in applying computer algebraic techniques to study the symmetry properties of molecules and clusters. A special attention is placed in this thesis work on the flexibility of the Bethe package, which makes it possible to implement another applications of symmetry. This implementation is very reasonable, because some of the most complicated steps of the possible future applications are already realized within the Bethe. For instance, the vibrational coordinates in terms of the internal displacement vectors for the Wilson's method and the same coordinates in terms of cartesian displacement vectors as well as the Clebsch-Gordan coefficients for the Jahn-Teller problem are generated in the present version of the program. For the Jahn-Teller problem, moreover, use of the computer-algebraic tool seems to be even inevitable, because this problem demands an analytical access to the adiabatic potential and, therefore, can not be realized by the numerical algorithm. However, the ability of the Bethe package is not exhausted by applications, mentioned in this thesis work. There are various directions in which the Bethe program could be developed in the future. Apart from (i) studying of the magnetic properties of materials and (ii) optical transitions, interest can be pointed out for (iii) the vibronic spectroscopy, and many others. Implementation of these applications into the package can make Bethe a much more powerful tool.

Multilevel multitrait-multimethod model: application to the measurement of egocentered social networks

Our goal in this paper is to assess reliability and validity of egocentered network data using multilevel analysis (Muthen, 1989, Hox, 1993) under the multitrait-multimethod approach. The confirmatory factor analysis model for multitrait-multimethod data (Werts & Linn, 1970; Andrews, 1984) is used for our analyses. In this study we reanalyse a part of data of another study (Kogovšek et al., 2002) done on a representative sample of the inhabitants of Ljubljana. The traits used in our article are the name interpreters. We consider egocentered network data as hierarchical; therefore a multilevel analysis is required. We use Muthen's partial maximum likelihood approach, called pseudobalanced solution (Muthen, 1989, 1990, 1994) which produces estimations close to maximum likelihood for large ego sample sizes (Hox & Mass, 2001). Several analyses will be done in order to compare this multilevel analysis to classic methods of analysis such as the ones made in Kogovšek et al. (2002), who analysed the data only at group (ego) level considering averages of all alters within the ego. We show that some of the results obtained by classic methods are biased and that multilevel analysis provides more detailed information that much enriches the interpretation of reliability and validity of hierarchical data. Within and between-ego reliabilities and validities and other related quality measures are defined, computed and interpreted

An integrating approach to the study of burnout in University Professors. 'Una aproximaci??n integradora al estudio del burnout en los profesores de Universidad'

Resumen tomado de la publicaci??n

A new approach to the classification of mammographic masses and normal breast tissue

A new approach to mammographic mass detection is presented in this paper. Although different algorithms have been proposed for such a task, most of them are application dependent. In contrast, our approach makes use of a kindred topic in computer vision adapted to our particular problem. In this sense, we translate the eigenfaces approach for face detection/classification problems to a mass detection. Two different databases were used to show the robustness of the approach. The first one consisted on a set of 160 regions of interest (RoIs) extracted from the MIAS database, being 40 of them with confirmed masses and the rest normal tissue. The second set of RoIs was extracted from the DDSM database, and contained 196 RoIs containing masses and 392 with normal, but suspicious regions. Initial results demonstrate the feasibility of using such approach with performances comparable to other algorithms, with the advantage of being a more general, simple and cost-effective approach

Administrative authorization for the demolition of urban rental units pursuant to the law of 1964: a spanish example of problematic over-activity in the application of transitional laws

Transitional provisions are defined as the set of regulations that rule juridical relationships on the occasion of a legislative change. Out of this context of law succession, their indiscriminate application can lead to serious inconsistencies. The analysis of a Spanish private law example is offered to illustrate this fact. It concerns the administrative authorization for the demolition of rented buildings in the cities. A regulation repealed more than fifteen years ago and however widespread utilised on ancient constructions that, after recent urban development, have acquired great economic value; something that in the end explains the current importance of such provisions. What is happening in Spain: denaturalization of the original  figure due to a mixture of formalist interpretations and speculative market interests, is presented here to call the attention on the necessary limitation of transitional provisions’ effects.

Dilemmas in Regards to the Restitution of Lands in Colombia

The text argues that, even if different sectors of society have some strategic points of agreement on the issue of land, which converge on the specific issue of restitution, they strongly disagree on various other points. On one side are some who advocate “pure restitution” and consequently support a restitution policy that focuses on correcting the illegal dispossession and clarifying land titles and individual rights to property, which would serve to boost the land market and allow for rural development policies that modernize agricultural production, fundamentally based on large, corporate ownership. On the other end of the spectrum are advocates of what we call “comprehensive restitution,” who promote adopting a restitution policy that meets the requirements not only of corrective justice but also of recognition and redistribution, advancing the interest of peasant, indigenous, and afro-Colombian communities.

Application of agent-based modeling to the study of gender stereotypes

Gender stereotypes are sets of characteristics that people believe to be typically true of a man or woman. We report an agent-based model (ABM) that simulates how stereotypes disseminate in a group through associative mechanisms. The model consists of agents that carry one of several different versions of a stereotype, which share part of their conceptual content. When an agent acts according to his/her stereotype, and that stereotype is shared by an observer, then the latter’s stereotype strengthens. Contrarily, if the agent does not act according to his/ her stereotype, then the observer’s stereotype weakens. In successive interactions, agents develop preferences, such that there will be a higher probability of interaction with agents that confirm their stereotypes. Depending on the proportion of shared conceptual content in the stereotype’s different versions, three dynamics emerge: all stereotypes in the population strengthen, all weaken, or a bifurcation occurs, i.e., some strengthen and some weaken. Additionally, we discuss the use of agent-based modeling to study social phenomena and the practical consequences that the model’s results might have on stereotype research and their effects on a community

Nongenetic inheritance, linguistic competence, prenatal experience and behavior manipulation: recent contributions from behavioral neurobiology and neuropsychology to the explanation of behavior

This article gives an overview of presuppositions and explanations posed by behaviorist psychology (particularly its radical branch), cognitive–nativist sciences (i.e. psycholinguistics and a branch of cognitive psychology) and other disciplines regarding important psychological events such as anxiety, stress, fear, mood states and language. In relation to the discussion of environment versus genetics, contributions from behavioral neurobiology and neuropsychology are added, showing evidence of traits that can be multigenerationally inherited in a non-genetic way, which have an impact thought the life of organisms and on their way of interacting with the environment; ways in which behavior can be altered by recently unsuspected environmental agents or events, and the overlooked role of prenatal experiences in the explanation of behavior. The evidence calls into question presuppositions made by the academic disciplines listed above, and suggests alternative behavior reinterpretations and explanations

Contribution from neuropsychology to the study of semantic memory

Semantic memory has been studied from various fields. The first models emerged from cognitive psychology from the hand of the division proposed by Tulving between semantic and episodic memory. Over the past thirty years there have been parallel developments in the fields of psycholinguistics, cognitive psychology and cognitive neuropsychology. The present work is to review the contributions that have emerged within the neuropsychology to the study of semantic memory and to present an updated overview of the points of consensus. First, it is defined the term "semantics" conceptually within the field of neuropsychology. Then, there is a dichotomy that passes through both psychological and neuropsychological models on semantic memory: the existence of modals versus amodal representations. Third, there are  developed the main theoretical models in neuropsychology that emerged in an attempt to explain categoryspecific semantic deficits. Finally, more robust contributions and points that still generate some discussion are reviewed.

Advances and limitations in the attention to the problems of housing and urban land in Mexico. An approach from the legal-institutional frame

In this work we analyze the reforms carried out by the Mexican state in the nineties of the 20th century, in the items concerning the policies of housing and urban land, based on an exhaustive review of the main actions, programs and changes in the legal and institutional frame that applies for each of these fields. The nineties represent a "breaking point" in the way the State considers the satisfaction of the right to the housing and attends the offer of urbanized land for a tidy and sustainable urban development. In this period of time, the approach of direct intervention in developing and financing housing and creation of land reserves has changed into another one, ruled by the logic of the market. The balance to the first decade of the 21st century is ambiguous, as neither the housing policy has solved the housing shortage for low-income population, nor the land policy has eliminated the illegal urban growth.

An approximation to the standard of living index: the Colombian case

El documento busca mostrar las principales propiedades de un indicador de estándar de vida dentro del enfoque teórico de Amartya Sen. Establecemos un puente entre conceptos tales como: bienestar económico, bienestar, logro de agencia y estándar de vida. La metodología del Optimal scaling fue usada para probar las propiedades de Monotonicidad, No independencia de alternativas irrelevantes, Concavidad, informatividad y sustituibilidad.

An Approach to the Integration of Skills in English Teaching. 'Un acercamiento a la integración de habilidades en la enseñanza del inglés'.

Resumen de la revista

From the assimilation to the acceptance of the other? : educational policy for indigenous peoples in Latin America and the 'intercultural bilingual education' policy in Chile. '¿De la asimilación a la aceptación del otro? : política educativa para pueblos indígenas en América Latina y la política de 'educación intercultural bilingüe' en Chile'.

Monográfico con el título: 'Desde la diversidad hacia la desigualdad: ¿destino inexorable de la globalización?'. Resumen basado en el de la publicación