Empirical study of correlated survival times for recurrent events with proportional hazards margins and the effect of correlation and censoring.

Background: In longitudinal studies where subjects experience recurrent incidents over a period of time, such as respiratory infections, fever or diarrhea, statistical methods are required to take into account the within-subject correlation. Methods: For repeated events data with censored failure, the independent increment (AG), marginal (WLW) and conditional (PWP) models are three multiple failure models that generalize Cox"s proportional hazard model. In this paper, we revise the efficiency, accuracy and robustness of all three models under simulated scenarios with varying degrees of within-subject correlation, censoring levels, maximum number of possible recurrences and sample size. We also study the methods performance on a real dataset from a cohort study with bronchial obstruction. Results: We find substantial differences between methods and there is not an optimal method. AG and PWP seem to be preferable to WLW for low correlation levels but the situation reverts for high correlations. Conclusions: All methods are stable in front of censoring, worsen with increasing recurrence levels and share a bias problem which, among other consequences, makes asymptotic normal confidence intervals not fully reliable, although they are well developed theoretically.

Influence of rootstocks and pruning times on yield and on nutrient content and extraction in 'Niagara Rosada' grapevine

The objective of this work was to evaluate the influence of rootstocks and pruning times on yield and on nutrient content and extraction by pruned branches and harvested bunches of 'Niagara Rosada' grapevine in subtropical climate. The rootstocks 'IAC 766', 'IAC 572', 'IAC 313', 'IAC 571-6', and '106-8 Mgt' were evaluated. Treatments consisted of a combination between five rootstocks and three pruning times. At pruning, fresh and dry matter mass of branches were evaluated to estimate biomass accumulation. At harvest, yield was estimated by weighing of bunches per plant. Branches and bunches were sampled at pruning and at harvest, respectively, for nutrient content analysis. Nutrient content and dry matter mass of branches and bunches were used to estimate total nutrient extraction. 'Niagara Rosada' grapevine grafted onto the 'IAC 572' rootstock had the highest yield and dry matter mass of bunches, which were significantly different from the ones observed in 'Niagara Rosada'/'IAC 313'. 'Niagara Rosada' grafted onto the 'IAC 572' rootstock extracted the largest quantity of K, P, Mg, S, Cu, and Fe, differing from 'IAC 313' and 'IAC 766' in K and P extraction, and from '106-8 Mgt' in Mg and S extraction. Winter pruning results in higher yield, dry matter accumulation by branches, and total nutrient content and extraction.

Federal Dynamics in Times of Economic and Financial Crisis

The global economic and financial crisis is a challenge for all governments, but particularly for federal states because divided and/or shared territorial powers make federations susceptible to coordination problems in fiscal policy making. This article explores the effects of the ongoing crisis on federal relations. Three kinds of problems that may become the cause of federal tensions and conflicts are evoked: opportunism of subgovernments, centralisation and erosion of solidarity among members of the federation. Our analysis of fiscal policies and federal conflicts of 11 federations between 2007 and the present reveals three kinds of coordination problems: shirking in the use of federal government grants, rent-seeking in equalisation payments, and over-borrowing and over-spending. Our results show that shirking remained limited to few cases and occurred only in the first part of the crisis. However, rent-seeking and over-borrowing and over-spending led to a reduction of solidarity among subgovernments and to increased regulation of the fiscal discretion of the members of the federation. Subsequently, tensions in federal relations increased - although only in one case did this challenged the federal order.

Religion in Times of Crisis

Religion is alive and well all over the world, especially in times of personal, political, and social crisis. Even in Europe, long regarded the most "secular" continent, religion has taken centre stage in how people respond to the crises associated with modernity, or how they interact with the nation-state. In this book, scholars working in and on Europe offer fresh perspectives on how religion provides answers to existential crisis, how crisis increases the salience of religious identities and cultural polarization, and how religion is contributing to changes in the modern world in Europe and beyond. Cases from Poland to Pakistan and from Ireland to Zimbabwe, among others, demonstrate the complexity and ambivalence of religion's role in the contemporary world.

An experience beyond continuous assessment activities: virtual tour to the medieval medicinal plant garden of the Pedralbes monastery

[eng] The group of teaching innovation in the area of Botany (GIBAF), University of Barcelona (UB), is raised each year to design new accreditation activities under continuous evaluation framework. We present the experience carried out during the academic year 2008-09 in the course of Pharmaceutical Botany. The aim has been to involve students for a semester in the authorship of a tutored project immediately useful and of easy permanence, beyond its assessment proving usefulness. The Medicinal Plants Garden of the Monastery of Pedralbes has been used as a resource and a collaboration agreement has been signed between the UB faculty and the Institute of Culture of Barcelona. The students have developed the work using the Moodle platform CampusvirtualUB into five stages which included preparation of files by students that have been modified in some steps following the various feedbacks from teachers. At the beginning of the activity, students were provided with a complete schedule of activities, the schedule for its implementation, and a total of 18 forced-use library resources. Finally, through Google sites, a website has been implemented, allowing for a virtual tour of the garden, documenting by referenced literature 50 medicinal plants for their nomenclature, botanical description, distribution, uses historical, current and future) and toxicity. The result of the activity was presented at a public ceremony in the Monastery of Pedralbes and is available at: http://sites.google.com/site/jardimedievalpedralbes/ [spa] El grupo de innovación docente integrado por profesores del área de Botánica (GIBAF) de la Universidad de Barcelona (UB) se plantea cada curso el diseño de nuevas actividades acreditativas en el marco de la evaluación continuada. Se presenta la experiencia llevada a cabo durante el curso 2008-09 en la asignatura Botánica Farmacéutica. El objetivo ha sido implicar durante un semestre a los estudiantes en la autoría de un proyecto tutorizado de inmediata utilidad y clara perdurabilidad, más allá de su utilidad acreditativa. Como recurso se ha utilizado el Jardín de Plantas Medicinales del Monasterio de Pedralbes y se ha firmado un convenio de colaboración docente entre la UB y el Instituto de Cultura de Barcelona. Los estudiantes han realizado el trabajo utilizando la plataforma Moodle del Campus virtual de la UB en cinco etapas que han incluido la confección de unas fichas que se han ido modificando en función de las diversas retroacciones de los profesores. Al inicio de la actividad, se facilitó a los estudiantes el cronograma completo de la actividad, la pauta para su realización, así como un total de 18 recursos bibliográficos de uso obligado. Finalmente, a través de GoogleSites, se ha realizado una web que permite realizar un paseo virtual por el jardín, documentando de forma referenciada para las 50 plantas medicinales su nomenclatura, descripción botánica, distribución, usos (históricos, actuales y futuros) y toxicidad. El resultado de la actividad fue presentado en un acto público en el Monasterio de Pedralbes y puede consultarse en: http://sites.google.com/site/jardimedievalpedralbes/

Sant Llorenç del Montsec (La Noguera): un despoblat medieval

The medieval deserted village of St. Lloreng, a fortified place in the west lands of Catalonia, in Lleida, near Aragon, is studied from its origins in 11th. century unti1 14th.C. The growth and evolution of population during this time is shown by the houses, placed between the castle and the church, some so simply with only one room, some wider. The authors don't know why the village became deserted, but they indicate the possible move of the population into the limits of the Ager valley.

The Omega model: from bankruptcy to occupation times in the red

Ruin occurs the first time when the surplus of a company or an institution is negative. In the Omega model, it is assumed that even with a negative surplus, the company can do business as usual until bankruptcy occurs. The probability of bankruptcy at a point of time only depends on the value of the negative surplus at that time. Under the assumption of Brownian motion for the surplus, the expected discounted value of a penalty at bankruptcy is determined, and hence the probability of bankruptcy. There is an intrinsic relation between the probability of no bankruptcy and an exposure random variable. In special cases, the distribution of the total time the Brownian motion spends below zero is found, and the Laplace transform of the integral of the negative part of the Brownian motion is expressed in terms of the Airy function of the first kind.

La noció d'Espanya a la Catalunya medieval

A partir de la necessitat de conèixer les bases del propi present i d'assolir puntals on arrelar els discursos de futur, ara i adés les diferents col·lectivitats es remeten als orígens, "l'obsessió pels orígens" deia Marc Bloch. I aquests, en una Europa que parla de l'Edat Mitjana com la infantesa de la pròpia identitat, s'aboquen a una època medieval on conflueixen -en el que des de la llunyania de la nostra quotidianitat pot semblar una amalgama poc destriada- tant les realitats gresoladores dels actuals signes d'identitat culrurals, socials i lingüístics, com les projeccions que delerosament hi cerquen les justificacions del present i els condicionants del furur. Així doncs, convé apamar bé l'espai físic i conceptual per definir adientment la realitat existent en aquells moments que han alimentat les arrels d'identitats que, travessant diferents estímuls al llarg de la història, han menat fins als nostres dies.

El naixement d'un vilar medieval: Moredell (Gironès) en època carolíngia

This is the description of the birth, development and transformations of a small rural community in carolingian epoch through the written documentation and the analysis of the landscape.