Molecular and pedigree measures of relatedness provide similar estimates of inbreeding depression in a bottlenecked population.

Individual-based estimates of the degree of inbreeding or parental relatedness from pedigrees provide a critical starting point for studies of inbreeding depression, but in practice wild pedigrees are difficult to obtain. Because inbreeding increases the proportion of genomewide loci that are identical by descent, inbreeding variation within populations has the potential to generate observable correlations between heterozygosity measured using molecular markers and a variety of fitness related traits. Termed heterozygosity-fitness correlations (HFCs), these correlations have been observed in a wide variety of taxa. The difficulty of obtaining wild pedigree data, however, means that empirical investigations of how pedigree inbreeding influences HFCs are rare. Here, we assess evidence for inbreeding depression in three life-history traits (hatching and fledging success and juvenile survival) in an isolated population of Stewart Island robins using both pedigree- and molecular-derived measures of relatedness. We found results from the two measures were highly correlated and supported evidence for significant but weak inbreeding depression. However, standardized effect sizes for inbreeding depression based on the pedigree-based kin coefficients (k) were greater and had smaller standard errors than those based on molecular genetic measures of relatedness (RI), particularly for hatching and fledging success. Nevertheless, the results presented here support the use of molecular-based measures of relatedness in bottlenecked populations when information regarding inbreeding depression is desired but pedigree data on relatedness are unavailable.

AlleleRetain: a program to assess management options for conserving allelic diversity in small, isolated populations.

Preserving genetic health is an important aspect of species conservation. Allelic diversity is particularly important to conserve, as it provides capacity for adaptation and thus enables long-term population viability. Allele retention is difficult to predict beyond one generation for real populations with complex demography and life-history traits, so we developed a computer model to simulate allele retention in small populations. AlleleRetain is an individual-based model implemented in r and can be applied to assess management options for conserving allelic diversity in small populations of animals with overlapping generations. AlleleRetain remedies the limitations of similar existing software, and its source code is freely available for further modification. AlleleRetain and its supporting materials can be downloaded from https://sites.google.com/site/alleleretain/ or CRAN (http://cran.r-project.org).

Multimodel inference in ecology and evolution: challenges and solutions.

Information theoretic approaches and model averaging are increasing in popularity, but this approach can be difficult to apply to the realistic, complex models that typify many ecological and evolutionary analyses. This is especially true for those researchers without a formal background in information theory. Here, we highlight a number of practical obstacles to model averaging complex models. Although not meant to be an exhaustive review, we identify several important issues with tentative solutions where they exist (e.g. dealing with collinearity amongst predictors; how to compute model-averaged parameters) and highlight areas for future research where solutions are not clear (e.g. when to use random intercepts or slopes; which information criteria to use when random factors are involved). We also provide a worked example of a mixed model analysis of inbreeding depression in a wild population. By providing an overview of these issues, we hope that this approach will become more accessible to those investigating any process where multiple variables impact an evolutionary or ecological response.

Historic and contemporary levels of genetic variation in two New Zealand passerines with different histories of decline.

We compared historic and contemporary genetic variation in two threatened New Zealand birds (saddlebacks and robins) with disparate bottleneck histories. Saddlebacks showed massive loss of genetic variation when extirpated from the mainland, but no significant loss of variation following a severe bottleneck in the 1960s when the last population was reduced from approximately 1000 to 36 birds. Low genetic variation was probably characteristic of this isolated island population: considerably more genetic variation would exist in saddlebacks today if a mainland population had survived. In contrast to saddlebacks, contemporary robin populations showed only a small decrease in genetic variation compared with historical populations. Genetic variation in robins was probably maintained because of their superior ability to disperse and coexist with introduced predators. These results demonstrate that contemporary genetic variation may depend more greatly on the nature of the source population and its genetic past than it does on recent bottlenecks.

Impact of a newly opened prison on an accident and emergency department.

OBJECTIVE: To determine the impact of a newly opened prison on an accident and emergency (A&E) department. METHOD: A new category B prison opened in April 1999, the first privately run prison in Scotland and the third largest in population. All prisoners referred to the A&E department for treatment were identified prospectively during the first year after the opening of the prison. RESULTS: 99 prisoners and four members of staff attended during the one year period. Ages ranged from 18-64 years with a mean age of 29.8 years. Presentations were as a result of deliberate self harm (22%), injury after violence (18%), sports injury (15%), surgical condition (15%), medical illness (13%), accidental injury (9%), ENT problem (2%), and miscellaneous (6%). Thirty seven prisoners (35.6%) were admitted to the hospital. Further review at outpatient clinics was arranged for 15 prisoners. One prisoner died, the result of suicide by hanging. The remaining prisoners were returned to the prison for further management by the prison medical and nursing team. Twelve prisoners re-attended a total of 37 times, ranging from twice to a maximum of eight visits. Some 42.3% of attendances were during "working hours" (09.00-17.00) and 57.7% attended "out of hours" (17.00-09.00). Twenty four referrals (23.1%) were deemed inappropriate by the prison medical team on retrospective review. Sixteen of these occurred "out of hours". Forty one prisoners (39.4%) were known to have a history of injecting drug misuse. Including re-attenders, 59 presentations (56.7%) to the A&E department had a history of injecting drug misuse. Of these 41 prisoners, 11 (26.8%) were hepatitis C positive, with eight of these having a positive polymerase chain reaction test. No prisoners had HIV and only one prisoner was hepatitis B positive. CONCLUSION: The opening of the prison resulted in only a slight increase in the workload of the A&E department. A significant proportion of prisoners were admitted to the hospital highlighting the practical and logistical problems of managing people restrained and in custody. Most cases can be safely referred back to the prison. Increased input is required from the prison medical team when dealing with deliberate self harm, frequent attenders, and "out of hours" referrals. All A&E staff must be aware of the increased risk of hepatitis C infection when dealing with a confined prison population.

Social factors associated with increases in tuberculosis notifications.

This study assessed the contribution of immigration and deprivation to the changes in tuberculosis notifications in Liverpool over the last 20 yrs. Ethnic origin was retrospectively assigned to all named cases from 1974 to 1995. Average tuberculosis rates were calculated for the 33 council wards in Liverpool for 1981-1985 and 1991-1995. Multiple regression was used to determine the independent effects of socioeconomic and population measures from the 1981 and 1991 censuses in explaining these ward-based rates. Since 1974, there has been a steady increase in the percentage of non-Caucasian cases of tuberculosis, from 8.7% in 1975-1977, 15.1% in 1981-1983, 17.5% in 1987-1989 to 28.0% in 1993-1995. Multiple regression analysis showed that in 1981 only unemployment had a significant independent relationship with tuberculosis rates, but in 1991 two indices of deprivation and ethnicity had a significant influence. The increasing proportion of non-Caucasian tuberculosis cases, both while the number of notifications was declining before 1987 and increasing afterwards, is not necessarily consistent with the concept that immigration has influenced the recent increase. However, the fact that ethnicity now independently explains some of the council ward variations but did not in the early 1980s suggests that immigration does influence the distribution of disease within the city.

The validation event: a critical appraisal?

Apart from the perennial concern with finance, questions of 'quality' and 'accountability' will be the principle themes in the higher education debate in the 1990s. The whole issue of 'quality' and 'accountability' has become critically important to the success or otherwise of colleges of nursing and midwifery in convincing their multiple stakeholders (clients, patients, students and purchasers) that they should have a place in the marketing of nursing and midwifery education. The validation process is an important component of the formalized quality assurance mechanism of a course. There have, however, been little or no empirical data relating to the effect of validation processes on quality of courses and, more important, in the long term, quality of care. The following issues are explored in the paper. How are 'quality' and 'accountability' defined within the context of a market orientated system? How is 'peer review' to be interpreted within a purchaser led system? Are practice outcomes prioritised within educationally led, practice-based courses? Is there a part to play for continuing external regulation? We suggest that recent developments in nursing and midwifery education have often been undermined, during validation events, by structural processes for conformity. Such a regression to the conventional has been strengthened by the absence of new conceptions of quality deliberately designed to match these innovatory courses. Conceptions, that is, framed in terms distinct from the traditional model in which quality in higher education tends to be regarded as largely an attribute of disciplinary knowledge. Finally, we suggest that the decisive determinant of professional skill, is the personal standards, the professionalism and the self-respect of the individual teacher.