Fractionation and compositional studies of rabbit skeletal muscle membranes

The observations of Hooke (1665), Schleiden & Schwann (1839) and Virchow (1855) led to the identification of the cell as the basic structural unit of living material. In the intervening years, it has been firmly established that the chemical processes which underlie the proper functioning, development and reproduction of the organism are cellular activities. The development of the electron microscope has enabled cell structure to be studied in detail. A picture of the cell as an entity with a complex and highly organised internal structure has emerged from the work of Palade, Porter, Fernandez-Moran and many others. Although cells from different tissues and organisms differ in aspects of their structure and consequently in function, they have several features in common. A retentive membrane encloses a number of cell constituents, which include membrane-enclosed subcellular structures known as organelles. The cells of most tissues also contain a reticulum or system of branching tubules. The interplay of the biochemical activities of these structures enables the cell to function. Almost thirty years ago, Claude, Palade, Schneider, Hogeboom, de Duve and others set out to analytically fractionate the subcellular components obtained after the fragmentation of liver cells. This approach has become known as subcellular fractionation, and signalled a major conceptual breakthrough in biochemistry (reviewed by de Duve, 1964, 1967, 1971). The significance of this breakthrough has been underlined by the award of the 1974 Nobel Prize in Medicine to de Duve, Palade and Claude. This thesis is concerned with the application of subcellular fractionation techniques to the separation and characterisation of the membrane systems of the rabbit skeletal muscle cell.

Alcohol income and health: a complicated but desirable mix

The aim of this thesis is to examine if a difference exists in income for different categories of drinkers in Ireland using the 2007 Slán data set. The possible impact of alcohol consumption on health status and health care utilisation is also examined. Potential endogeneity and selection bias is accounted for throughout. Endogeneity is where an independent variable included in the model is determined within the context of the model (Chenhall and Moers, 2007). An endogenous relationship between income and alcohol and between health and alcohol is accounted for by the use of separate income equations and separate health status equations for each category of drinker similar to what was done in previous studies into the effects of alcohol on earnings (Hamilton and Hamilton, 1997; Barrett, 2002). Sample selection bias arises when a sector selection is non-random due to individuals choosing a particular sector because of their personal characteristics (Heckman, 1979; Zhang, 2004). In relation to alcohol consumption, selection bias may arise as people may select into a particular drinker group due to the fact that they know that by doing so it will not have a negative effect on their income or health (Hamilton and Hamilton, 1997; Di Pietro and Pedace, 2008; Barrett, 2002). Selection bias of alcohol consumption is accounted for by using the Multinomial Logit OLS Two Step Estimate as proposed by Lee (1982), which is an extension of the Heckman Probit OLS Two Step Estimate. Alcohol status as an ordered variable is examined and possible methods of estimation accounting for this ordinality while also accounting for selection bias are looked at. Limited Information Methods and Full Information Methods of estimation of simultaneous equations are assessed and compared. Findings show that in Ireland moderate drinkers have a higher income compared with abstainers or heavy drinkers. Some studies such as Barrett (2002) argue that this is as a consequence of alcohol improving ones health, which in turn can influence ones productivity which may ultimately be reflected in earnings, due to the fact that previous studies have found that moderate levels of alcohol consumption are beneficial towards ones health status. This study goes on to examine the relationship between health status and alcohol consumption and whether the correlation between income and the consumption of alcohol is similar in terms of sign and magnitude to the correlation between health status and the consumption of alcohol. Results indicate that moderate drinkers have a higher income than non or heavy drinkers, with the weekly household income of moderate drinkers being €660.10, non drinkers being €546.75 and heavy drinkers being €449.99. Moderate Drinkers also report having a better health status than non drinkers and a slightly better health status than heavy drinkers. More non-drinkers report poor health than either moderate or heavy drinkers. As part of the analysis into the effect of alcohol consumption on income and on health status, the relationship between other socio economic variables such as gender, age, education among others, with income, health and alcohol status is examined.

Aesthetic campaigns and counter-campaigns. Jorge Luis Borges and a century of the Argentine detective story (1877-1977)

This cultural history of Argentine crime fiction involves a comprehensive analysis of the literary and critical traditions within the genre, paying particular attention to the series of ‘aesthetic campaigns’ waged by Jorge Luis Borges and others during the period between 1933 and 1977. The methodological approach described in the introductory chapter builds upon the critical insight that in Argentina, generic discourse has consistently been the domain, not only of literary critics in the traditional mould, but also of prominent writers of fiction and specialists from other disciplines, effectively transcending the traditional tripartite ‘division of labour’ between writers, critics and readers. Chapter One charts the early development of crime fiction, and contextualises the evolution of the classical and hardboiled variants that were to provide a durable conceptual framework for discourse in the Argentine context. Chapter Two examines a number of pioneering early works by Argentine authors, before analysing Borges’ multi-faceted aesthetic campaign on behalf of the ‘classical’ detective story. Chapter Three examines a transitional period for the Argentine crime genre, book-ended by the three Vea y Lea magazine-sponsored detective story competitions that acted as a vital stimulus to innovation among Argentine writers. It includes a substantial treatment of the work of Rodolfo Walsh, documenting his transition from crime writer and anthologist to pioneer of the non-fiction novel and investigative journalism traditions. Chapter Four examines the period in which the novela negra came to achieve dominance in Argentina, in particular the aesthetic counter-campaigns conducted by Ricardo Piglia and others on behalf of the hard-boiled variant. The study concludes with a detailed analysis of Pablo Leonardo’s La mala guita (1976), which is considered as a paradigmatic example of crime fiction in Argentina in this period. The final chapter presents conclusions and a summary of the dissertation, and recommendations for further research.

The ecology of the Irish stoat

The Irish stoat, Mustela erminea hibernica (Thomas and Barrett-Hamilton), has been regarded as an intermediate between the British stoat and the weasel. In this study Irish stoats, mainly from road casualties, were collected and studied. A small number were also live-trapped and radio-tracked. Thus information was gathered on the stoat’s ecology, in particular its form (size and coat colours), reproduction, food habits, parasites, habitat utilisation mortality and predation. The Irish stoats studied were clearly not intermediate in size between British stoats and weasels. They showed considerable size overlap with British stoats, and marked size variation within Ireland. It is argued that size of stoats is determined by food supply early in life. The ventral coat pattern of Irish stoats is apparently unique in the Palaearctic, being similar to that of some stoats found on the west coast of North America. It is argued that this is an example of parallel evolution resulting from adaptation to similar climatic conditions. The stoats were reproductively active in spring and summer. Food consisted mainly of rabbits, but rats, birds, shrews mice and voles were also consumed. Mites were the most numerous ectoparasites, followed by lice, ticks and fleas. Damage by the parasitic nematode Skrjabingylus nasicola was found more frequently in female stoat skulls. Stoats were frequently found in a variety of habitats, both open and wooded. Some of the radio-tracked stoats climbed trees. Dens used were often rat holes. Only one home range, that of a breeding female, was considered to have been accurately measured. It was 22 ha. in size. Mortality is known to have been caused by road accidents and domestic carnivores. It is argued that predation by raptorial birds is important to stoat populations. Results of this study are compared with information available from elsewhere.