Imposicions estructurals en el drenatge de la conca del riu Onyar (Girona)

The Onyar River basin is situated in the depression of la Selva. His origins are related to tectonic activity during Neogen in this region. In his evolution, we note a slowly and continuous downfall which directs the morphodinamical behaviour. In this sense, the drainage network has a directional trend towards the north, as consecuence of fault systems, and specially the N-S oriented one. A fault of this system has an important influence in the basin morphology, directs the drainage towards the north and avoids a closely drainage in the basin

Del Simbolisme a l'abstracció: l'ideal de la unitat de les arts en l'obra de Kandinsky i Mondrian, 1886-1936

Aquesta tesi explora els orígens de la pintura abstracta des d'un punt de vista eminentment conceptual. Parteix de la hipòtesi que l'abstracció es pot considerar la culminació dels ideals estètics del Simbolisme finisecular; i considera que un dels elements de continuïtat entre Simbolisme i abstracció fou l'ideal de l'obra d'art total o Gesamtkunstwerk. La tesi estudia els pintors Vassily Kandinsky i Piet Mondrian per mostrar, a través de l'anàlisi de les seves obres i textos, que aquest ideal d'obra total fou per ambdós un leit-motiv fonamental en la seva evolució vers l'abstracció. En el cas de Kandinsky s'estudien especialment les seves composicions escèniques, i en el cas de Mondrian, l'arranjament del seu estudi, projectes en el marc dels quals es va desenvolupar la seva pintura. En ambdós casos, com també en el Simbolisme, el projecte de l'obra d'art total es considera tant des de la vessant artística, com en relació al seu valor utòpic.

Avaliação da aptidão física em alunos dos 11 aos 14 anos, praticantes e não praticantes desportivos : estudo de caso

Este estudo pretende caracterizar a Aptidão Física (ApF) de alunos que praticam e que não praticam atividade desportiva extracurricular, verificando a sua evolução durante um ano letivo e ao longo da idade. A amostra é constituída por 146 alunos, 78 do género masculino e 68 do género feminino, do 5º ao 9° ano de escolaridade, do Agrupamento de Escolas Josefa de Óbidos, com idades compreendidas entre os 11 e os 14 anos. A avaliação da ApF é feita através dos critérios previstos na bateria de testes do Fitnessgram, nas provas de Vaivem (CA), Força Média (FM), Senta e alcança (FL) e o nível e tipo de prática desportiva através de questionário. Para análise dos dados são utilizados procedimentos estatísticos essenciais, com um nível de significância 5% (p<0,05). Aplica-se o Independente-Samples T-test na comparação de não praticantes e praticantes, género e idade e o Teste t-pares na evolução da avaliação inicial para a final, usando o SPSS (versão 19). Das principais conclusões retira-se que: (1) Os níveis de ApF são crescentes e significativos do 1º para o 2º momento em não praticantes, excetuando quando analisados por idade na FM em rapazes e em raparigas não praticantes de 13 e 14 anos; na CA e FL nos não praticantes, rapazes de 12 e 13 anos e raparigas de 12 anos; (2) na comparação de não praticantes e praticantes verificam-se valores estatisticamente significativos em todos os testes, à exceção, do teste da FM, na avaliação inicial e na final. Quando analisados por idade verificam-se igualmente significativos na CA em rapazes de 11, 13 e 14 anos e nas raparigas de 13 anos. Idêntico comportamento ocorre na FL em rapazes de 14 anos e raparigas de 12 e 14 anos, em ambas as avaliações; (3) os níveis de ApF aumentam com a idade - a diferença mais acentuada ocorre dos 11 para os 12 anos na FM (rapazes praticantes e raparigas não praticantes) e na CA (rapazes e raparigas não praticantes); verificam-se pequenas variações na FL, sendo estatisticamente significativas, com decréscimo acentuado, dos 13 para os 14 anos em não praticantes e com aumento significativo, para as mesmas idades, nos praticantes.

Dispositivos de iluminação natural: a sua evolução na arquitectura

Este estudo apresenta uma perspectiva da ‘janela’, como o dispositivo mais frequente de iluminação, na sua evolução e significado na arquitectura. A sua capacidade de caracterizar tendências e estilos arquitectónicos, permanece desde as primeiras referências históricas até aos elementos desenvolvidos e associados à iluminação natural dos dias de hoje. O interesse por este tema surgiu, principalmente, por ser o elemento arquitectónico que desde sempre permitiu a entrada de luz natural nas construções. Foi sempre um dos pontos de ligação e relação do interior com o exterior. Em determinadas situações tornou-se num elemento tão discreto, que nos passou despercebido, além de ter sido ocasionalmente desvalorizado. A janela ou dispositivo de iluminação natural, quando utilizado correctamente pode trazer muitos benefícios à arquitectura, assim como proporcionar conforto térmico sem necessidade de gastos energéticos excessivos.

The “Fashionable Knowledge” of Management Consulting

In the evolution of strategic disciplines much of the knowledge produced has been widely diffused by the management consulting industry. But can this sector be regarded as knowledge intensive activity based on true structure of expertise knowledge? One way to understand if we can consider that sector as a source of knowledge dissemination is realizing its relationship with the market in terms of knowledge, rather than identify only as a set of static techniques to be applied as in most of times they have been doing. This article presents itself as a reflection about the real reasons for the increasing use ofmanagement consulting services, indicating simultaneously that can really be a true field of opportunities for the academic class if the study will focused in the establishment and institutionalization of micropractices (strategy-as-practice) that there are used and its implications in terms of organizational results.

Soberanía e integración en América Latina (Tema Central)

El artículo hace referencia al desarrollo de la soberanía y las nuevas formas de regionalismo en América Latina. En esta lógica, el “nuevo regionalismo” surge en los últimos años bajo condiciones internas y externas que se traducen en el surgimiento de nuevas formas regionales como ALBA, UNASUR, CELAC. Adicionalmente, se recalca la persistencia de obstáculos a la integración regional como la soberanía nacional, pero al mismo tiempo se plantea enfrentar los mencionados desafíos a través de cambios conceptuales del término soberanía, en función de una estrategia a largo plazo que genere una gobernanza regional.

Lagrangian analysis of low level anthropogenic plume processing across the North Atlantic

The photochemical evolution of an anthropogenic plume from the New-York/Boston region during its transport at low altitudes over the North Atlantic to the European west coast has been studied using a Lagrangian framework. This plume, originally strongly polluted, was sampled by research aircraft just off the North American east coast on 3 successive days, and 3 days downwind off the west coast of Ireland where another aircraft re-sampled a weakly polluted plume. Changes in trace gas concentrations during transport were reproduced using a photochemical trajectory model including deposition and mixing effects. Chemical and wet deposition processing dominated the evolution of all pollutants in the plume. The mean net O3 production was evaluated to be -5 ppbv/day leading to low values of O3 by the time the plume reached Europe. Wet deposition of nitric acid was responsible for an 80% reduction in this O3 production. If the plume had not encountered precipitation, it would have reached the Europe with O3 levels up to 80-90 ppbv, and CO levels between 120 and 140 ppbv. Photochemical destruction also played a more important role than mixing in the evolution of plume CO due to high levels of both O3 and water vapour showing that CO cannot always be used as a tracer for polluted air masses, especially for plumes transported at low altitudes. The results also show that, in this case, an important increase in the O3/CO slope can be attributed to chemical destruction of CO and not to photochemical O3 production as is often assumed.

Reflections: 50 Years of Medieval Archaeology, 1957-2007

This volume celebrates the 50th anniversary of the Society for Medieval Archaeology (established in 1957), presenting reflections on the history, development and future prospects of the discipline. The papers are drawn from a series of conferences and workshops that took place in 2007-2008, in addition to a number of contributions that were commissioned especially for the volume. They range from personal commentaries on the history of the Society and the growth of the subject, to historiographical, regional and thematic overviews of major trends in the evolution and current practice of medieval archaeology in Britain. Critical overviews are presented of the archaeology of medieval landscapes, buildings and material culture; new developments in the scientific study of medieval health, diet and materials; and innovations in social approaches to medieval archaeology. A series of papers on southern Europe provide a comparative perspective, featuring overviews on medieval archaeology in Italy, Spain and southeastern Europe.

Uses of airborne scanning laser altimetry for river flood modelling and coastal geomorphology

Two ongoing projects at ESSC that involve the development of new techniques for extracting information from airborne LiDAR data and combining this information with environmental models will be discussed. The first project in conjunction with Bristol University is aiming to improve 2-D river flood flow models by using remote sensing to provide distributed data for model calibration and validation. Airborne LiDAR can provide such models with a dense and accurate floodplain topography together with vegetation heights for parameterisation of model friction. The vegetation height data can be used to specify a friction factor at each node of a model’s finite element mesh. A LiDAR range image segmenter has been developed which converts a LiDAR image into separate raster maps of surface topography and vegetation height for use in the model. Satellite and airborne SAR data have been used to measure flood extent remotely in order to validate the modelled flood extent. Methods have also been developed for improving the models by decomposing the model’s finite element mesh to reflect floodplain features such as hedges and trees having different frictional properties to their surroundings. Originally developed for rural floodplains, the segmenter is currently being extended to provide DEMs and friction parameter maps for urban floods, by fusing the LiDAR data with digital map data. The second project is concerned with the extraction of tidal channel networks from LiDAR. These networks are important features of the inter-tidal zone, and play a key role in tidal propagation and in the evolution of salt-marshes and tidal flats. The study of their morphology is currently an active area of research, and a number of theories related to networks have been developed which require validation using dense and extensive observations of network forms and cross-sections. The conventional method of measuring networks is cumbersome and subjective, involving manual digitisation of aerial photographs in conjunction with field measurement of channel depths and widths for selected parts of the network. A semi-automatic technique has been developed to extract networks from LiDAR data of the inter-tidal zone. A multi-level knowledge-based approach has been implemented, whereby low level algorithms first extract channel fragments based mainly on image properties then a high level processing stage improves the network using domain knowledge. The approach adopted at low level uses multi-scale edge detection to detect channel edges, then associates adjacent anti-parallel edges together to form channels. The higher level processing includes a channel repair mechanism.

Bridging the gaps between agricultural policy, land-use and biodiversity

The fate of biodiversity is intimately linked to agricultural development. Policy reform is an important driver of changes in agricultural land-use, but there is considerable spatial variation in response to policy and its potential impact on biodiversity. We review the links between policy, land-use and biodiversity and advocate a more integrated approach. Ecologists need to recognize that wildlife-friendly farming is not the only land-use strategy that can be used to conserve biodiversity and to research alternative options such as land sparing. There is also a need for social scientists and ecologists to bring their approaches together, so that land-use change and its consequences can be investigated in a more holistic way.

Insight overview: natural selection 150 years on

The theory of evolution by natural selection has prospered in its first 150 years and provides a consistent account of species as highly adapted and rare survivors in the struggle for existence. It now faces the challenge of finding order in the evolution of complex systems, including human society.

Fungicide resistance: the dose rate debate

It makes economic sense to use as little fungicide as possible on a crop. In many settings, it is common to apply less than the manufacturer's recommended dose. If sources of disease are scarce, or conditions are unsuitable for it to increase, the reduced control from a low dose may be adequate. In other cases, a big reduction in dose may cause little reduction in control, again permitting savings - especially for growers prepared to run a little risk. But the label recommendations for most fungicides state that to avoid resistance, a full dose must always be used. Are individual cost-savings therefore endangering everyone's access to an exceptionally useful tool? The emergence of fungicide resistance is evolution in action. In all cases, it involves the genetic replacement of the original susceptible population of the pathogen by a new population with genetically distinct biochemistry, which confers resistance. The resistant biochemistry originates in rare genetic mutations, so rare that initially the population is hardly altered. Replacement of susceptible forms by resistant ones happens because, with fungicide present, the resistant form multiplies more rapidly than the susceptible form. The key point to notice is that only the relative rates of multiplication of the resistant and susceptible types are involved in the evolution of resistance. The absolute rates are irrelevant.

Genesis and expansion of metazoan transcription factor gene classes

We know little about the genomic events that led to the advent of a multicellular grade of organization in animals, one of the most dramatic transitions in evolution. Metazoan multicellularity is correlated with the evolution of embryogenesis, which presumably was underpinned by a gene regulatory network reliant on the differential activation of signaling pathways and transcription factors. Many transcription factor genes that play critical roles in bilaterian development largely appear to have evolved before the divergence of cnidarian and bilaterian lineages. In contrast, sponges seem to have a more limited suite of transcription factors, suggesting that the developmental regulatory gene repertoire changed markedly during early metazoan evolution. Using whole- genome information from the sponge Amphimedon queenslandica, a range of eumetazoans, and the choanoflagellate Monosiga brevicollis, we investigate the genesis and expansion of homeobox, Sox, T- box, and Fox transcription factor genes. Comparative analyses reveal that novel transcription factor domains ( such as Paired, POU, and T- box) arose very early in metazoan evolution, prior to the separation of extant metazoan phyla but after the divergence of choanoflagellate and metazoan lineages. Phylogenetic analyses indicate that transcription factor classes then gradually expanded at the base of Metazoa before the bilaterian radiation, with each class following a different evolutionary trajectory. Based on the limited number of transcription factors in the Amphimedon genome, we infer that the genome of the metazoan last common ancestor included fewer gene members in each class than are present in extant eumetazoans. Transcription factor orthologues present in sponge, cnidarian, and bilaterian genomes may represent part of the core metazoan regulatory network underlying the origin of animal development and multicellularity.

Phylogenetic mixture models can reduce node-density artifacts

We investigate the performance of phylogenetic mixture models in reducing a well-known and pervasive artifact of phylogenetic inference known as the node-density effect, comparing them to partitioned analyses of the same data. The node-density effect refers to the tendency for the amount of evolutionary change in longer branches of phylogenies to be underestimated compared to that in regions of the tree where there are more nodes and thus branches are typically shorter. Mixture models allow more than one model of sequence evolution to describe the sites in an alignment without prior knowledge of the evolutionary processes that characterize the data or how they correspond to different sites. If multiple evolutionary patterns are common in sequence evolution, mixture models may be capable of reducing node-density effects by characterizing the evolutionary processes more accurately. In gene-sequence alignments simulated to have heterogeneous patterns of evolution, we find that mixture models can reduce node-density effects to negligible levels or remove them altogether, performing as well as partitioned analyses based on the known simulated patterns. The mixture models achieve this without knowledge of the patterns that generated the data and even in some cases without specifying the full or true model of sequence evolution known to underlie the data. The latter result is especially important in real applications, as the true model of evolution is seldom known. We find the same patterns of results for two real data sets with evidence of complex patterns of sequence evolution: mixture models substantially reduced node-density effects and returned better likelihoods compared to partitioning models specifically fitted to these data. We suggest that the presence of more than one pattern of evolution in the data is a common source of error in phylogenetic inference and that mixture models can often detect these patterns even without prior knowledge of their presence in the data. Routine use of mixture models alongside other approaches to phylogenetic inference may often reveal hidden or unexpected patterns of sequence evolution and can improve phylogenetic inference.

Adaptation and speciation: what can F-st tell us?

A useful way of summarizing genetic variability among different populations is through estimates of the inbreeding coefficient, F-st. Several recent studies have tried to use the distribution of estimates of F-st from individual genetic loci to detect the effects of natural selection. However, the promise of this approach has yet to be fully realized owing to the pervasive dogma that this distribution is highly dependent on demographic history. Here, I review recent theoretical results that indicate that the distribution of estimates of F-st is generally expected to be robust to the vagaries of demographic history. I suggest that analyses based on it provide a useful first step for identifying candidate genes that might be under selection, and explore the ways in which this information can be used in ecological and evolutionary studies.