Biodiversity of macrozoobenthos in a large river, the Austrian Danube, including quantitative studies in a free-flowing stretch below Vienna: a short review

The Danube is ca. 2850 km in length and is the second largest river in Europe. The Austrian part of the Danube falls 156 metres in altitude over its 351 km length and, since the early 1950s, the river has been developed into a power-generating waterway, so that the continuity of the river is now interrupted by ten impounded areas. Only two stretches of the original free-flowing river are left, the Wachau region (above river-km 2005, west of Vienna) and the region downstream from the impoundment at Vienna (river-km 1921). Most of the recent theories and concepts related to invertebrates, in the context of the ecology of running waters, are based on studies on small streams, whereas investigations of large rivers have played a minor role for a long time, mainly due to methodological difficulties. The authors' recent detailed studies on macroinvertebrates in the free-flowing section of the Danube below Vienna, provide an excellent opportunity to survey or restate scientific hypotheses on the basis of a large river. In this review the main interest focuses on the investigation of biodiversity, i.e. the number of species and their relative proportions in the whole invertebrate community, as well as major governing environmental factors. The article summarises the species composition, the important environmental variables at the river cross-section and the effect of upstream impoundment on the riverbed and its fauna.

Quantifying Earthquake Collapse Risk of Tall Steel Braced Frame Buildings Using Rupture-to-Rafters Simulations

This thesis examines collapse risk of tall steel braced frame buildings using rupture-to-rafters simulations due to suite of San Andreas earthquakes. Two key advancements in this work are the development of (i) a rational methodology for assigning scenario earthquake probabilities and (ii) an artificial correction-free approach to broadband ground motion simulation. The work can be divided into the following sections: earthquake source modeling, earthquake probability calculations, ground motion simulations, building response, and performance analysis.

As a first step the kinematic source inversions of past earthquakes in the magnitude range of 6-8 are used to simulate 60 scenario earthquakes on the San Andreas fault. For each scenario earthquake a 30-year occurrence probability is calculated and we present a rational method to redistribute the forecast earthquake probabilities from UCERF to the simulated scenario earthquake. We illustrate the inner workings of the method through an example involving earthquakes on the San Andreas fault in southern California.

Next, three-component broadband ground motion histories are computed at 636 sites in the greater Los Angeles metropolitan area by superposing short-period (0.2~s-2.0~s) empirical Green's function synthetics on top of long-period ($>$ 2.0~s) spectral element synthetics. We superimpose these seismograms on low-frequency seismograms, computed from kinematic source models using the spectral element method, to produce broadband seismograms.

Using the ground motions at 636 sites for the 60 scenario earthquakes, 3-D nonlinear analysis of several variants of an 18-story steel braced frame building, designed for three soil types using the 1994 and 1997 Uniform Building Code provisions and subjected to these ground motions, are conducted. Model performance is classified into one of five performance levels: Immediate Occupancy, Life Safety, Collapse Prevention, Red-Tagged, and Model Collapse. The results are combined with the 30-year probability of occurrence of the San Andreas scenario earthquakes using the PEER performance based earthquake engineering framework to determine the probability of exceedance of these limit states over the next 30 years.

A short thesis on arc-welding

During the past few years the attention of architects, engineers and others encased in or connected with the building industry has been attracted to the possibilities of the application of welding processes to the joining of structural members. As oxy-acetylene welding was developed before electric arc welding became perfected it was only natural that the gas torch should be first considered. It developed however on examination of the two processes that while acetylene welding gave better results in most cases it was only in the hands of experts that it could consistently outscore the arc as a welding medium. Arc-welding has the advantage over the acetylene process, where each individual operator must use his own judgement as to the proper flame, in that a squad of arc-welders can work under the direction of a single expert supervisor who accepts the responsibility of fixing the current value and of determining the proper size of welding rod to be used on any given type of work.

Leitura e Alegoria em Fausto de Fernando Pessoa

Esta dissertação busca compreender de que forma a ideia de alegoria, concebida por Walter Benjamin e desenvolvida posteriormente por Paul de Man, pode lançar luz sobre certos aspectos do poema dramático Fausto do poeta português Fernando Pessoa. Pessoa entendeu seu Fausto como sendo encerrado pelo embate entre Inteligência e Vida, do qual a Inteligência sairia sempre vencida. Portanto, o presente estudo busca entender a derrota da Inteligência em termos dos aspectos alegóricos do poema em questão. Para tal, certas conexões estabelecidas tanto por Walter Benjamin quanto por Paul de Man serão pensadas como nosso ponto de partida. O que se tem em mente, neste ponto, são as conexões feitas por Benjamin entre alegoria e progressão e o entendimento de Paul de Man de que toda narrativa alegórica contaria a história de um fracasso de leitura. Desta forma, a derrota da Inteligência é compreendida tanto no sentido de progressão quanto no de um fracasso de leitura. Ademais, como o Fausto de Fernando Pessoa é composto de poemas que lidam com o embate entre Inteligência e Vida, tal relação será também ponto central desta dissertação

Dielectric recovery of short A-C arcs between low-boiling-point electrodes

The re-ignition characteristics (variation of re-ignition voltage with time after current zero) of short alternating current arcs between plane brass electrodes in air were studied by observing the average re-ignition voltages on the screen of a cathode-ray oscilloscope and controlling the rates of rise of voltage by varying the shunting capacitance and hence the natural period of oscillation of the reactors used to limit the current. The shape of these characteristics and the effects on them of varying the electrode separation, air pressure, and current strength were determined.

The results show that short arc spaces recover dielectric strength in two distinct stages. The first stage agrees in shape and magnitude with a previously developed theory that all voltage is concentrated across a partially deionized space charge layer which increases its breakdown voltage with diminishing density of ionization in the field-tree space. The second stage appears to follow complete deionization by the electric field due to displacement of the field-free region by the space charge layer, its magnitude and shape appearing to be due simply to increase in gas density due to cooling. Temperatures calculated from this second stage and ion densities determined from the first stage by means of the space charge equation and an extrapolation of the temperature curve are consistent with recent measurements of arc value by other methods. Analysis or the decrease with time of the apparent ion density shows that diffusion alone is adequate to explain the results and that volume recombination is not. The effects on the characteristics of variations in the parameters investigated are found to be in accord with previous results and with the theory if deionization mainly by diffusion be assumed.

A Poética de Adélia Prado: espaço de articulação entre língua portuguesa e língua literária

A tese estuda a obra poética de Adélia Prado sob o ponto de vista da Estilística. Mostra que a metáfora é o recurso mais afeito a construir a língua literária e, no caso da poetisa, modelá-la em português. O estudo atesta que a linguagem conotativa da poetisa alcança os três níveis da língua e promove o inesperado e o distante da expressão comum. Afirma a importância da polifonia e da intertextualidade , além da excelência do discurso indireto livre na criação literária, não só da poetisa, mas de todo uso da língua portuguesa como ferramenta de expressão poética, principalmente se a intenção do autor é criar o discurso surrealista. A pesquisa mostra que há, na obra, um grande número de poemas em que predomina a linguagem religiosa católica. Ocorre a expressão da alma feminina , marcada com orgulho pela poetisa. A autora cria prosodemas, inaugura neologismos ,aproveitando todos os processos de criação vocabular. Assim, a obra se notabiliza pelo aproveitamento da sonoridade das palavras, pela escolha lexical inédita, por uma estrutura frasal apositiva, evocativa, sucinta e nominal, não escravizada às regras do registro culto como padrão literário. A tese reconhece que a autora lida eficientemente com as classes de palavras, com a construção nominal e com uma estruturação sintática peculiar, em que sobressai a oração adjetiva com função de sujeito, apesar de conter verbo: a oração adjetiva subjetivada. A essência da pesquisa são os conjuntos metafóricos, verdadeiros modelos universais, que permitem reconhecer a possível existência de uma língua literária em português. No mesmo contexto, focaliza um grupo de poemas chamados de telegráficos, curtos e de teor filosófico. Tal qualidade metafórica mostra a importância da poetisa Adélia Prado para a articulação da língua literária em língua portuguesa

A facultatividade da concordância: português formal real versus gramática escolar

No ensino de língua nacional, concordância é um dos tópicos em cujo aprendizado observa dificuldade por parte dos discentes, principalmente pelo grande número de regras facultativas das gramáticas, que muitas vezes não levam em conta o uso formal real da língua. Este trabalho visa a descrever esse uso, a partir da observação de um corpus do caderno opinião de jornais de grande circulação, confrontando os resultados com as prescrições da norma gramatical escolar, a fim de separar, em tais prescrições, a parte aproveitável da não coincidente com a realidade do corpus, se for o caso. Pretende-se, dessa forma, contribuir para a boa qualidade do ensino da língua portuguesa nos níveis fundamental e médio, especificamente no que se refere à concordância

A (her)story of ones own: fiction and autobiography in Julia Alvarezs novels

Escritoras migrantes frequentemente publicam romances autobiográficos que mesclam ficção com suas histórias pessoais. Essas escritoras usam suas experiências pessoais para discutir questões coletivas relacionadas aos diversos tipos de deslocamento associados ao processo diaspórico. As migrações em massa das ex-colônias para as metrópoles dos países desenvolvidos cresceram significantemente após a Segunda Guerra Mundial, gerando ao mesmo tempo contato mais próximos e conflitos entre culturas. Essa dissertação pretende analisar os romances autobiográficos How the García Girls Lost their Accents (1991) e Yo! (1997) da escritora dominicana-americana Julia Alvarez, A família Alvarez migrou para os Estados Unidos em 1960 devido a perseguição política. Em seus romances, a escritora lida com os traumas do deslocamento e com o processo de crescimento de meninas divididas entre valores culturais diferentes. Pretendo discutir como Alvarez, em sua prática autobiográfica, problematiza questões relacionadas à migração, como gênero, hibridismo cultural, memória lacunar e identidades fragmentadas. Também analiso como essas narrativas contestam as convenções formais tanto do gênero autobiográfico como da ficção, frisando o quanto o limite entre o real e o fictício, entre o privado e o político, é tênue

Systematic liquidity: commonality and inter-temporal variation in the Portuguese stock market

[EN] The aim of this paper is to study systematic liquidity at the Euronext Lisbon Stock Exchange. The motivation for this research is provided by the growing interest in financial literature about stock liquidity and the implications of commonality in liquidity for asset pricing since it could represent a source of non-diversifiable risk. Namely, it is analysed whether there exist common factors that drive the variation in individual stock liquidity and the causes of the inter-temporal variation of aggregate liquidity. Monthly data for the period between January 1988 and December 2011 is used to compute some of the most used proxies for liquidity: bid-ask spreads, turnover rate, trading volume, proportion of zero returns and the illiquidity ratio. Following Chordia et al. (2000) methodology, some evidence of commonality in liquidity is found in the Portuguese stock market when the proportion of zero returns is used as a measure of liquidity. In relation to the factors that drive the inter-temporal variation of the Portuguese stock market liquidity, the results obtained within a VAR framework suggest that changes in real economy activity, monetary policy (proxied by changes in monetary aggregate M1) and stock market returns play an important role as determinants of commonality in liquidity.