Reconstructing paternal genotypes to infer patterns of sperm storage and sexual selection in the hawksbill turtle.

Postcopulatory sperm storage can serve a range of functions, including ensuring fertility, allowing delayed fertilization and facilitating sexual selection. Sperm storage is likely to be particularly important in wide-ranging animals with low population densities, but its prevalence and importance in such taxa, and its role in promoting sexual selection, are poorly known. Here, we use a powerful microsatellite array and paternal genotype reconstruction to assess the prevalence of sperm storage and test sexual selection hypotheses of genetic biases to paternity in one such species, the critically endangered hawksbill turtle, Eretmochelys imbricata. In the majority of females (90.7%, N = 43), all offspring were sired by a single male. In the few cases of multiple paternity (9.3%), two males fertilized each female. Importantly, the identity and proportional fertilization success of males were consistent across all sequential nests laid by individual females over the breeding season (up to five nests over 75 days). No males were identified as having fertilized more than one female, suggesting that a large number of males are available to females. No evidence for biases to paternity based on heterozygosity or relatedness was found. These results indicate that female hawksbill turtles are predominantly monogamous within a season, store sperm for the duration of the nesting season and do not re-mate between nests. Furthermore, females do not appear to be using sperm storage to facilitate sexual selection. Consequently, the primary value of storing sperm in marine turtles may be to uncouple mating and fertilization in time and avoid costly re-mating.

Detection of single nucleotide polymorphisms within a sequence of a gene associated with prostate cancer using a fluorophore-tagged DNA probe.

Single nucleotide polymorphisms within a sequence of a gene associated with prostate cancer were identified using oligodeoxynucleotide probe sequences bearing internal anthracene fluorophores proximal to the SNP site. Depending upon the nature of the synthesised target sequences, probe-target duplex formation could lead to enhanced or attenuated fluorescence emission from the anthracene, enabling detection of a proximal base-pair as either matching or mismatching.

The functioning of primary school learners with paraplegia/paraparesis in mainstream schools in the Western Cape, South Africa. An exploratory study.

PURPOSE: This study explores the reality of implementing policy guidelines that promote the inclusion of learners with disabilities in mainstream schools. According to the department of education in South Africa, learners who can satisfactorily be educated in an ordinary or mainstream school should be accommodated there. METHOD: The Craig handicap assessment and reporting technique were used to identify activity limitations and participation restrictions of learners with paraplegia/paraparesis in the mainstream school setting in the Western Cape, South Africa. The Craig hospital inventory of environmental factors identified contextual factors that facilitate or restrict the participation of learners. The views of the learners, teachers and parents were compared in order to identify the facilitators and barriers that influence the participation of physically disabled learners in mainstream schooling. The study population comprised 15 learners between the ages of 6 and 14 years old with paraplegia/paraparesis, their parents and relevant class teachers in 13 mainstream schools of the Western Cape, South Africa. RESULTS: Findings indicate that cognitive independence and mobility are the two areas that most restricted the participation of the learners in the school. Resource availability, social support and equality were critical to facilitating the inclusion of learners at mainstream schools. CONCLUSIONS: It is recommended that a comprehensive research project be undertaken. Teacher support and training is essential for keeping the educators motivated and informed. Physical assistance to the learners should be provided in a structured and appropriate way. Physical accessibility, transport and medical information should be addressed at the institutional (school) level and is not the responsibility of the parents or caregivers of the disabled learners.