Evolutionary ecology of host-symbiont interactions

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Long Term Evolution of the Size Distribution of Portuguese Cities

In this paper we study the evolution of the Portuguese urban system from 1864 to 2001. We apply the rank-size model and use rank-size estimates to describe the evolution of city-size hierarchy. Non paretian behaviour of the distribution is examined by adding a quadratic term to the basic equation of the model. Our results enhance two different processes in the evolution of urban system: until the middle of the twentieth century urban growth was accompanied by population concentration in the largest cities and proliferation of small cities; afterwards growth benefits middle size cities, reinforced in the last decades by heavy population losses in the two largest cities. From the association between the characteristics and evolving pattern of city size distribution and the spatial pattern of urban growth, it appears that the non paretian behaviour of city size distribution in the last decades can be linked to the particular growth process of cities located in the proximity of the central cities of the two metropolitan areas of Portugal’s mainland. In order to obtain a better understanding of the dynamics of the Portuguese urban system we examine the movements in the ranking of cities. We also analyse the existence of spatial correlation in the process of urban hierarchy restructuring.

The evolution of city size distribution in Portugal: 1864-2001

The rank-size model - which states that the size distribution of cities in a country follows a Pareto distribution - has been recognized as one of those stylised facts or amazing empirical regularities, in spatial economics. A common problem in city size distribution studies concerns the definition of “cities”, namely the consistency of those definitions over time. In this paper we use a city-proper data base which uses a consistent definition of cities from 1864 to 1991. Portugal is a country with long established national borders and whose mainland urban system shows a constant number of cities over that period. In Portugal, empirical evidence on city size distribution based on census data shows that two large cities dominate the urban system, associated with a large number of very small cities and a clear deficit of medium-size cities. In this paper we analyse the evolution of the rank size exponent and examine the effect of varying city size cut-offs on the estimated value of that exponent. Then, we study the deviations of the rank-size distribution from linearity. Finally, we explore the dynamics underlying the evolution of the urban system by examining the relationship between city growth rates and city size. Keywords: city size distribution, Zipf’s law, rank-size, urban hierarchy, urban primacy

The evolution of city size distribution in Portugal: 1864-2001

The rank-size model - which states that the size distribution of cities in a country follows a Pareto distribution - has been recognized as one of those stylized facts or amazing empirical regularities, in spatial economics. A common problem in city size distribution studies concerns the definition of “cities”, namely the consistency of those definitions over time. In this paper we use a city-proper data base which uses a consistent definition of cities from 1864 to 1991. Portugal is a country with long established national borders and whose mainland urban system shows a constant number of cities over that period. In Portugal, empirical evidence on city size distribution based on census data shows that two large cities dominate the urban system, associated with a large number of very small cities and a clear deficit of medium-size cities. In this paper we analyse the evolution of the rank size exponent and examine the effect of varying city size cut-offs on the estimate value of that exponent. Then, we study the deviations of the rank-size distribution from linearity. Finally, we explore the dynamics underlying the evolution of the urban system by examining the relationship between city growth rates and city size.city size distribution, Zipf’s law, urban hierarchy, urban primacy

Long term evolution of the size distribution of Portuguese cities

In this paper we study the evolution of the Portuguese urban system from 1864 to 2001. We apply the rank-size model and use rank-size estimates to describe the evolution of city-size hierarchy. NonParetian behavior of the distribution is examined by adding a quadratic term to the basic equation of the model. Our results enhance two different processes in the evolution of urban system: until the middle of the twentieth century urban growth was accompanied by population concentration in the largest cities; afterwards growth benefits middle size cities, reinforced in the last decades by heavy population losses in the two largest cities. From the association between the characteristics and evolving pattern of city size distribution and the spatial pattern of urban growth, it appears that the nonParetian behavior of city size distribution in the last decades can be linked to the particular growth process of cities located in the proximity of the central cities of the two metropolitan areas of mainland Portugal. In order to obtain a better understanding of the dynamics of the Portuguese urban system we examine the movements in the ranking of cities, through a Markov chain process. We also analyse the existence of spatial correlation in the process of urban hierarchy restructuring.Urban hierarchy, rank-size distribution, urban growth, Markov processes

Constructing three emotion knowledge tests from the invariant measurement approach

Background. Psychological constructionist models like the Conceptual Act Theory (CAT) postulate that complex states such as emotions are composed of basic psychological ingredients that are more clearly respected by the brain than basic emotions. The objective of this study was the construction and initial validation of Emotion Knowledge measures from the CAT frame by means of an invariant measurement approach, the Rasch Model (RM). Psychological distance theory was used to inform item generation. Methods. Three EK testsemotion vocabulary (EV), close emotional situations (CES) and far emotional situations (FES)were constructed and tested with the RM in a community sample of 100 females and 100 males (age range: 18-65), both separately and conjointly. Results. It was corroborated that data-RM fit was sufficient. Then, the effect of type of test and emotion on Rasch-modelled item difficulty was tested. Significant effects of emotion on EK item difficulty were found, but the only statistically significant difference was that between "happiness" and the remaining emotions; neither type of test, nor interaction effects on EK item difficulty were statistically significant. The testing of gender differences was carried out after corroborating that differential item functioning (DIF) would not be a plausible alternative hypothesis for the results. No statistically significant sex-related differences were found out in EV, CES, FES, or total EK. However, the sign of d indicate that female participants were consistently better than male ones, a result that will be of interest for future meta-analyses. Discussion. The three EK tests are ready to be used as components of a higher-level measurement process.Fil: Delgado, Ana R.. Universidad de Salamanca; EspañaFil: Prieto, Gerardo. Universidad de Salamanca; EspañaFil: Burin, Debora Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Psicología; Argentin

Editorial

El desenvolupament d’internet permet configurar nous espais en l’àmbit digital més enllà de les fronteres geogràfiques i de les limitacions i barreres tradicionals, al mateix temps que genera noves necessitats de regulació i ordenació per part dels poders públics. Precisament, en aquest número es recullen algunes de les ponències i comunicacions presentades en el XII Congrés Internacional d’Internet, Dret i Política, dedicat al tema de la construcció d’un espai digital comú europeu (Building a European digital space).El desarrollo de internet permite configurar nuevos espacios en el ámbito digital más allá de las fronteras geográficas y de las limitaciones y barreras tradicionales, al mismo tiempo que genera nuevas necesidades de regulación y ordenación por parte de los poderes públicos. Precisamente, en este número se recogen algunas de las ponencias y comunicaciones presentadas en el XII Congreso Internacional de Internet Derecho y Política, dedicado al tema Building a european digital space.As the internet has developed, this has enabled new spaces to be created in the digital domain which have pushed geographical boundaries and limits, as well as more traditional boundaries, while also creating new requirements for regulation and classification by public authorities. That is precisely why some of the papers and talks delivered at the 12th International Internet, Law and Politics Congress, devoted to the topic of ‘Building a European digital space’, have been presented in this edition

Jornada sobre la asesoría fiscal y la organización de los despachos

El passat 24 de novembre del 2016 van tenir lloc les II Jornades d’Orientació Professional en Fiscalitat, en aquesta ocasió, dedicades a l’assessoria fiscal i l’organització dels despatxos. Les jornades, vinculades al màster universitari de Fiscalitat, les van organitzar els Estudis de Dret i Ciència Política de la Universitat Oberta de Catalunya com a instrument d’orientació  professional per als estudiants del màster i sota la direcció d’Ana María Delgado García, directora d’aquest, i de Rafael Oliver Cuello, professor col·laborador de Fiscalitat de la mateixa institució.On 24 November 2016 the 2nd Professional Guidance in Taxation Conference was held on the theme of “Tax advice and the organisation of firms". The Universitat Oberta de Catalunya’s Law and Political Science Department hosted this conference, connected to the Master’s degree in Taxation, as a means of professional guidance for the students reading for this Master’s course. It was led by Ana María Delgado García (Head of the UOC’s Master’s degree in Taxation) and Rafael Oliver Cuello (Assistant Lecturer in Taxation at the UOC)El pasado 24 de noviembre de 2016 tuvo lugar la II Jornada de Orientación Profesional en Fiscalidad, dedicada en esta ocasión a “La asesoría fiscal y la organización de los despachos”. Los Estudios de Derecho y Ciencia Política de la Universitat Oberta de Catalunya organizaron esta jornada, vinculada al Máster Universitario de Fiscalidad, como un instrumento de orientación profesional para los estudiantes de dicho Máster, y bajo la dirección de Ana María Delgado García (Directora del Máster Universitario de Fiscalidad de la UOC) y Rafael Oliver Cuello (Profesor Colaborador de Fiscalidad de la UOC)

Editorial

El fenomen actual de les dades massives o Big Data (és a dir, la generació i l’emmagatzematge d’una gran quantitat de conjunts de dades estructurades, no estructurades o semiestructurades a gran velocitat) s’accentua per l’auge de les xarxes socials o la proliferació del comerç electrònic, que requereixen una gestió molt elevada de grans volums d’informació. Així, les dades massives es nodreixen de diverses fonts: no tan sols d’internet i, especialment, de les xarxes socials, sinó també d’un altre tipus de fonts de l’àmbit públic i privat (tant les empreses com el sector públic recullen informació dels clients, els proveïdors, les operacions...). A més, la utilització generalitzada de dispositius mòbils, l’ús de satèl·lits, de sistemes GPS i de formats d’àudio i vídeo i la interconnexió d’ordinadors contribueixen a la generació d’aquestes dades. The modern-day phenomenon of Big Data (i.e. the high-speed generation and storage of a great quantity of structured, semi-structured and/or non-structured data sets) is being intensified by the ever more widespread use of social networks and the proliferation of e-commerce, which require sophisticated management of large volumes of information. Big Data thus has different sources. In addition to the internet and, in particular, social networks, there are sources of a different kind from the public and private sectors (businesses and public sector bodies alike compile information on their customers, users, suppliers, operations, etc.). Other contributing factors include mobile devices' omnipresence, GPS and satellite use, the consumption of audio and video material, and the interconnection of computers.El fenómeno actual de los macrodatos o Big Data (esto es, la generación y almacenamiento de gran cantidad de conjuntos de datos estructurados, no estructurados o semiestructurados a gran velocidad) se ve acentuado por el auge de las redes sociales o la proliferación del comercio electrónico, que requieren una elevada gestión de grandes volúmenes de información. Así, los macrodatos se nutren de diferentes fuentes: no solo de internet y, en especial, de las redes sociales, sino también de otro tipo de fuentes del ámbito público y privado (tanto las empresas como el sector público recopilan información acerca de sus clientes, proveedores, operaciones...). Además, contribuyen a la generación de tales datos la utilización generalizada de dispositivos móviles, el uso de satélites, de sistemas GPS y de formatos de audio y vídeo y la interconexión de ordenadores

Aspectos prácticos de las profesiones en el ámbito de la fiscalidad

El 10 d'octubre de 2014, els estudis de Dret i Ciència Política de la UOC, en el marc del màster universitari de Fiscalitat, van organitzar la «VI Jornada sobre Problemes Actuals de Fiscalitat. Aspectes Pràctics de les Professions en l'àmbit de la fiscalitat». La direcció va ser a càrrec d'Ana María Delgado García, catedràtica de Dret Financer i Tributari de la Universitat Oberta de Catalunya, i de Rafael Oliver Coll, consultor de Dret financer i tributari de la UOC.On 10 October 2014, the UOC's Law and Political Science Department held the 6th Conference on Current Taxation Problems on practical considerations for tax professionals as part of the University master's degree on taxation. The event was organized by Ana María Delgado García, Full Professor of Finance and Tax Law at the UOC, and Rafael Oliver Cuello, tutor for Finance and Tax Law at the UOC.El 10 de octubre de 2014, los Estudios de Derecho y Ciencia Política de la UOC, en el marco del máster universitario de Fiscalidad, organizaron la «VI Jornada sobre problemas actuales de fiscalidad. Aspectos prácticos de las profesiones en el ámbito de la fiscalidad». La dirección corrió a cargo de Ana María Delgado García, catedrática de Derecho Financiero y Tributario de la Universitat Oberta de Catalunya, y de Rafael Oliver Cuello, consultor de Derecho Financiero y Tributario de la Universitat Oberta de Catalunya