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This paper examines board effectiveness through an examination of the work and relationships of non-executive directors. It is based on 40 in-depth interviews with company directors, commissioned for the Higgs Review. The paper observes that research on corporate governance lacks understanding of the behavioural processes and effects of boards of directors. Whilst board structure, composition and independence condition board effectiveness it is the actual conduct of the non-executive vis-a`-vis the executive that determines board effectiveness. Data about behaviour and relationships on boards suggest that traditional theoretical divisions between agency and stewardship theory, and control versus collaboration models of the board do not adequately reflect the lived experience of non-executive directors and other directors on the board. Developing accountability as a central concept in the explanation of how boards operate effectively enables the paper to both challenge the dominant grip of agency theory on governance research and support the search for theoretical pluralism and greater understanding of board processes and dynamics. Practically, the work suggests that corporate governance reform will be undermined by prescription that supports distant perceptions of board effectiveness but not the actual effectiveness of boards.

A study was conducted to determine the fidelity of DNA synthesis catalyzed in vitro by the reverse transcriptase from a human immunodeficiency virus type 1 (HIV-1). Like other retroviral reverse transcriptases, the HIV-1 enzyme does not correct errors by exonucleolytic proofreading. Measurements with M13mp2-based fidelity assays indicated that the HIV-1 enzyme, isolated either from virus particles or from Escherichia coli cells infected with a plasmid expressing the cloned gene, was exceptionally inaccurate, having an average error rate per detectable nucleotide incorporated of 1/1700. It was, in fact, the least accurate reverse transcriptase described to date, one-tenth as accurate as the polymerases isolated from avian myeloblastosis or murine leukemia viruses, which have average error rates of approximately 1/17,000 and approximately 1/30,000, respectively. DNA sequence analyses of mutations generated by HIV-1 polymerase showed that base substitution, addition, and deletion errors were all produced. Certain template positions were mutational hotspots where the error rate could be as high as 1 per 70 polymerized nucleotides. The data are consistent with the notion that the exceptional diversity of the HIV-1 genome results from error-prone reverse transcription.

Pain in adults with sickle cell disease is the rule rather than the exception and is far more prevalent and severe than previous large-scale studies have portrayed. It is mostly managed at home; therefore, its prevalence is probably underestimated by health care providers, resulting in misclassification, distorted communication, and undertreatment.

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