Degree of multicollinearity and variables involved in linear dependence in additive-dominant models

The objective of this work was to assess the degree of multicollinearity and to identify the variables involved in linear dependence relations in additive-dominant models. Data of birth weight (n=141,567), yearling weight (n=58,124), and scrotal circumference (n=20,371) of Montana Tropical composite cattle were used. Diagnosis of multicollinearity was based on the variance inflation factor (VIF) and on the evaluation of the condition indexes and eigenvalues from the correlation matrix among explanatory variables. The first model studied (RM) included the fixed effect of dam age class at calving and the covariates associated to the direct and maternal additive and non-additive effects. The second model (R) included all the effects of the RM model except the maternal additive effects. Multicollinearity was detected in both models for all traits considered, with VIF values of 1.03 - 70.20 for RM and 1.03 - 60.70 for R. Collinearity increased with the increase of variables in the model and the decrease in the number of observations, and it was classified as weak, with condition index values between 10.00 and 26.77. In general, the variables associated with additive and non-additive effects were involved in multicollinearity, partially due to the natural connection between these covariables as fractions of the biological types in breed composition.

El camino hacia la integración de sistemas de gestión de la información científica : el TCD (Trinity College Dublin) como estudio de caso. CERIF y euroCRIS

Pablo de Castro, Director de GrandIR, describió la visión que el Grupo euroCRIS tiene de la infraestructura integrada de gestión de la información científica, compuesta por un sistema CRIS institucional, un repositorio de publicaciones y un repositorio de datos y software, y presentó el modelo de infraestructura integrada del Trinity College Dublin (TCD) como estudio de caso internacional. El sistema CRIS del TCD (TCD Research Support System o RSS), desde su primera versión en 2002, está basado en el estándar CERIF, un modelo de descripción de la actividad científica que está adquiriendo una progresiva relevancia como base de los sistemas CRIS en Europa, particularmente en el Reino Unido. Se citaron en la presentación los ensayos para incorporar CERIF al modelo de datos del software ePrints de repositorios, habilitándolo así para soportar parte de las tareas de recolección de información que realiza un CRIS, y la progresiva cobertura de CERIF a ámbitos tales como la gestión de datos de investigación.

A note on the degree sequences of graphs with restrictions

Degree sequences of some types of graphs will be studied and characterizedin this paper.

Aspects on Process Engineering in the Finnish Pulp and Paper Industry : Thesis for the Degree of Licentiate in Science of Technology

Process development will be largely driven by the main equipment suppliers. The reason for this development is their ambition to supply complete plants or process systems instead of single pieces of equipment. The pulp and paper companies' interest lies in product development, as their main goal is to create winning brands and effective brand management. Design engineering companies will find their niche in detail engineering based on approved process solutions. Their development work will focus on increasing the efficiency of engineering work. Process design is a content-producing profession, which requires certain special characteristics: creativity, carefulness, the ability to work as a member of a design team according to time schedules and fluency in oral as well as written presentation. In the future, process engineers will increasingly need knowledge of chemistry as well as information and automation technology. Process engineering tools are developing rapidly. At the moment, these tools are good enough for static sizing and balancing, but dynamic simulation tools are not yet good enough for the complicated chemical reactions of pulp and paper chemistry. Dynamic simulation and virtual mill models are used as tools for training the operators. Computational fluid dynamics will certainlygain ground in process design.

An induction programme for Bologna first-year bachelor’s degree students in Spain

Introduction. The current study describes the planning process and aims of the university reforms in Spain and suggests an innovative proposal, namely the design and evaluation of a week-long induction programme for first-year bachelor‟s degree students at the University of Lleida (Spain), organised within the European higher education framework. The purpose of this induction programme is to help new students adapt to university life. Method. A total of 102 students and ten lecturers were involved in the study. These participants responded questionnaires and interviews. We contrasted all the results in order to obtain some results that were useful to evaluate the induction programmee which the University introduced in the first four degrees. Results. Findings of the study revealed that participants gave very positive feedback regarding the programme, and the results also highlighted areas which could be improved. Conclusion. The new proposals clearly require a higher level of staff participation to make them work, highlighting the need for appropriate training of university staff and improving coordination with appropriate systems.

Integrability of a linear center perturbed by a fourth degree homogeneous polynomial

In this work we study the integrability of a two-dimensional autonomous system in the plane with linear part of center type and non-linear part given by homogeneous polynomials of fourth degree. We give sufficient conditions for integrability in polar coordinates. Finally we establish a conjecture about the independence of the two classes of parameters which appear in the system; if this conjecture is true the integrable cases found will be the only possible ones.

Integrability of a linear center perturbed by a fifth degree homogeneous polynomial

In this work we study the integrability of two-dimensional autonomous system in the plane with linear part of center type and non-linear part given by homogeneous polynomials of fifth degree. We give a simple characterisation for the integrable cases in polar coordinates. Finally we formulate a conjecture about the independence of the two classes of parameters which appear on the system; if this conjecture is true the integrable cases found will be the only possible ones.

Why Mathematics is essential in Biomedical Sciences degree?

Improvement of mathematical education and motivation of students in the mathematics" area is needed. What can be done? We introduce some ideas to generate the student"s interest for mathematics, because they often present difficulties in appreciating the relevance of mathematics and its role in the health sciences. We consider that a cornerstone in the strategy to attract the students" interest is linking the mathematics with real biomedical situations. We proceed in the following manner: We first present a real biomedical situation to produce interest and to generate curiosity. Second, we ask thought-provoking questions to students as: Which is the biomedical problem presented? Which is my knowledge on this situation? What could I do to solve this biomedical situation? Do I need some new mathematical concepts and procedures? Thereupon, the teacher explains the mathematical concepts necessary to solve the case presented, providing definitions, properties and tools for graphical display and/or mathematical calculations. In this learning methodology, ICTs were cornerstones for reaching the proposed competences. Furthermore, ICTs can also be used in the evaluative task in its two possible aspects: formative and for obtaining a qualification. Comments from students about this new mathematics teaching method indicate that the use of real biomedical case studies kept the lessons in mathematics interesting.

Percolation of spatially constrained Erdos-R enyi networks with degree correlations

Motivated by experiments on activity in neuronal cultures [J. Soriano, M. Rodr ́ıguez Mart́ınez, T. Tlusty, and E. Moses, Proc. Natl. Acad. Sci. 105, 13758 (2008)], we investigate the percolation transition and critical exponents of spatially embedded Erd̋os-Ŕenyi networks with degree correlations. In our model networks, nodes are randomly distributed in a two-dimensional spatial domain, and the connection probability depends on Euclidian link length by a power law as well as on the degrees of linked nodes. Generally, spatial constraints lead to higher percolation thresholds in the sense that more links are needed to achieve global connectivity. However, degree correlations favor or do not favor percolation depending on the connectivity rules. We employ two construction methods to introduce degree correlations. In the first one, nodes stay homogeneously distributed and are connected via a distance- and degree-dependent probability. We observe that assortativity in the resulting network leads to a decrease of the percolation threshold. In the second construction methods, nodes are first spatially segregated depending on their degree and afterwards connected with a distance-dependent probability. In this segregated model, we find a threshold increase that accompanies the rising assortativity. Additionally, when the network is constructed in a disassortative way, we observe that this property has little effect on the percolation transition.

La percepción de los estudiantes universitarios de Bellas Artes sobre sus dificultades de aprendizaje: el caso de las competencias de búsqueda y selección de información relevante

[spa]Identificar las dificultades halladas en el proceso de aprendizaje con la especial relación entre el esfuerzo y el logro experimentada por los estudiantes implica afrontar uno de los problemas fundamentales del aprendizaje. El presente artículo pretende abordar los aprendizajes vinculados a las competencias transversales de la búsqueda y selección de información desde el examen de la percepción de los estudiantes universitarios de arte en la realización de una carpeta de aprendizaje adaptada a la titulación y al perfil del estudiante. A partir de un enfoque cuantitativo, y mediante un estudio descriptivo transversal, se analizará la relación existente entre el esfuerzo realizado, los resultados de aprendizaje declarados y la relación entre ambas cuestiones -lo que a la postre define las dificultades- que manifiestan los estudiantes. [eng]This article aims to address the learning skills associated with the competence of searching and selecting information from the examination of the perceptions of art college students in the drawing up of a learning portfolio tailored to the degree and student profile. From a quantitative approach, and through a cross-sectional descriptive study, we will analyze the relationship between effort, stated learning outcomes and the relationship between these two issues what ultimately defines the difficulties which declare the students.

Dimensional structure of the Brief Symptom Inventory with Spanish College students.

The Brief Symptom Inventory is designed to assess symptoms of psychological disorders in adolescents and adults. The dimensional structure of the inventory, using exploratory and confirmatory factor analyses, was examined with a cross-sectional design in a Spanish sample of college students (N = 1,033, aged between 18 and 30 years old). Two hypotheses were tested: the original distribution of the items in nine factors, and the unidimensionality of the inventory. According to the results, a nine-factor structure seemed to be confirmed, although the strong intercorrelations found among the subscales indicated that these were measuring closely related constructs. The importance of cultural influences when assessing psychological symptoms and the need to develop national and sex norms for instruments that assess psychopathology, are also discussed.

Passport to a profession in the degree of pharmacy: how to integrate university students into the real world of work: "Passport to a profession in Pharmacy"

The incorporation of the Spanish university system into the European Higher Education Areahas brought about a series of adaptations. Among the recommendations is the inclusion ofan external training period in a company, which has resulted in significant changes in thedegree syllabus in order to balance the theoretical and practical education required by thestudents. This new framework has been legally confirmed by the Spanish Government and, inthe case of the University of Barcelona, by the publication of internal guidelines. Takingadvantage of this new opportunity to adapt the Pharmacy degree to real-world problems inindustry, the Dean’s team of the Faculty of Pharmacy, with the support of the Facultyadministrative staff and the Students Advisory Service, have assumed the challenge ofincluding a new subject in the syllabus entitled Training in Companies.In parallel, a new activity has been set up to ensure that the students choose the mostsuitable company department/job for them and to help them pass the company interview.Under the name of Passport to a Profession, a series of ten explanatory talks has beenscheduled every academic year. These talks deal with a broad range of topics aimed atproviding the students with the basic tools they will need to make the most of a companytraining period and to make headway in the professional world when they finish theirdegree. In addition, three Faculty of Pharmacy-Pharmaceutical company workshops and tworound-table conferences have been held in the last two years in order to bring the universityand industry together. Notably, the project to provide students with company training isexpanding on an international level, with two to three undergraduate students contractedevery year by a United Kingdom-based multinational pharmaceutical company.The statistical data of the whole process has been analysed for a more in-depthunderstanding of the activity and to improve the programme.