The object binary interface: C++ objects for evolvable shared class libraries

Object-oriented design and object-oriented languages support the development of independent software components such as class libraries. When using such components, versioning becomes a key issue. While various ad-hoc techniques and coding idioms have been used to provide versioning, all of these techniques have deficiencies - ambiguity, the necessity of recompilation or re-coding, or the loss of binary compatibility of programs. Components from different software vendors are versioned at different times. Maintaining compatibility between versions must be consciously engineered. New technologies such as distributed objects further complicate libraries by requiring multiple implementations of a type simultaneously in a program. This paper describes a new C++ object model called the Shared Object Model for C++ users and a new implementation model called the Object Binary Interface for C++ implementors. These techniques provide a mechanism for allowing multiple implementations of an object in a program. Early analysis of this approach has shown it to have performance broadly comparable to conventional implementations.

The Irish paradigm on the natural progression of hepatitis C virus infection: an investigation in a homogeneous patient population infected with HCV 1b (Review)

The aetiological agent of chronic hepatitis C is the hepatitis C virus. The hepatitis C virus is spread by parenteral transmission of body fluids, primarily blood or blood products. In 1989, after more than a decade of research, HCV was isolated and characterised. The hepatitis C viral genome is a positive-sense, single-stranded RNA molecule approximately 9.4 kb in length, which encodes a polyprotein of about 3100 amino acids. There are 6 main genotypes of HCV, each further stratified by subtype. In 1994, a cohort of women was identified in Ireland as having been iatrogenically exposed to the hepatitis C virus. The women were all young and exposed as a consequence of the receipt of HCV 1b contaminated anti-D immunoglobulin. The source of the infection was identified as an acutely infected female. As part of a voluntary serological screening programme involving 62,667 people, 704 individuals were identified as seropositive for exposure to the hepatitis C virus; 55.4% were found to be positive for the viral genome 17 years after exposure. Of these women 98% had evidence of inflammation, but suprisingly, a remarkable 49% showed no evidence of fibrosis. Clinicopathology and virological analysis has identified associations between viral load and the histological activity index for inflammation, and, between inflammation and levels of the liver enzyme alanine aminotransferase. Infection at a younger age appears to protect individuals from progression to advanced liver disease. Molecular analyses of host immunogenetic elements shows that particular class II human leukocyte associated antigen alleles are associated with clearance of the hepatitis C virus. Additional class II alleles have been identified that are associated with stable viraemia over an extended period of patient follow-up. Although, investigation of large untreated homogeneous cohorts is likely to become more difficult, as the efficacy of anti-viral therapy improves, further investigation of host and viral factors that influence disease progression will help provide an evidence based approach were realistic expectations regarding patient prognosis can be ascertained.

Law, poetry and medicine: the literate professionals in autonomous Gaelic Ireland, c.1250 - c.1630

This thesis is about a class of literate professionals that served as hereditary brehons, poets and doctors to the Gaelic aristocracy over a period from c.1250-c.1630. My investigation into these families brings together evidence from Gaelic and English sources to highlight the work these families did for their patrons, their status in society and their subsequent fall in the seventeenth century. Such a broad canvas allows us to observe the vibrancy of Gaelic literary culture as these families adapted to the changing political landscape to absorb new Anglo-Norman patrons and assimilated English and Continental ideas while maintaining their distinctive identity. I want to look beyond the ideology espoused by these families to look at the practical choices members of these families made to maintain their status and relevance in a changing social context. To do this I have chosen to focus on each of the three professions in individual chapters to highlight the continuities and changes within the professions and ultimately by comparing the three groups to gauge the success or failure of these professional families to adapt to the encroachment of the New English and the ultimate collapse of the Gaelic world. This thesis takes a holistic approach to these families by including branches of these families not engaged in the hereditary profession. It seeks to provide a broader picture of Gaelic society below the level of the aristocracy by looking at the geographic distribution of these families, their proximity to centres of power, and to land and sea routes that can indicate their involvement in alternative economic activities.