Recruitment and retention of tutors in problem-based learning: why teachers in medical education tutor

Introduction: Problem-based learning (PBL) is resource-intensive, particularly as it relates to tutors for small group learning. This study explores the factors that contributed to tutor participation in PBL in a medical training program, examining tutor recruitment and retention within the larger scope of teacher satisfaction and motivation in higher education. Method: From 2007 to 2010, following the introduction of new PBL-based curriculum in undergraduate medical education, all faculty members serving as tutors were invited to attend an interview as part of this study. Semi-structured interviews approximately one hour in length were conducted with 14 individuals- 11 who had tutored in PBL within the Faculty of Medicine and Dentistry and 3 faculty members who had chosen not to participate in PBL. Thematic analysis was employed as the framework for analysis of the data. Results: Seven factors were identified as affecting recruitment and retention of tutors in the undergraduate medical education program. Discussion: We suggest that identification and strengthening of the factors that promote tutor recruitment and retention may serve to strengthen PBL initiatives and, furthermore, may increase our understanding of motivation by academics in other aspects of medical education

Systematic revision of Southern African species in the genera Eptesicus, Neoromicia, Hypsugo and Pipistrellus (Chiroptera: Vespertilionidae).

Ph. D. University of KwaZulu-Natal 2005Abstract available in PDF file

Phenotypic convergence in genetically distinct lineages of a Rhinolophus species complex (Mammalia, Chiroptera)

Phenotypes of distantly related species may converge through adaptation to similar habitats and/or because they share biological constraints that limit the phenotypic variants produced. A common theme in bats is the sympatric occurrence of cryptic species that are convergent in morphology but divergent in echolocation frequency, suggesting that echolocation may facilitate niche partitioning, reducing competition. If so, allopatric populations freed from competition, could converge in both morphology and echolocation provided they occupy similar niches or share biological constraints. We investigated the evolutionary history of a widely distributed African horseshoe bat, Rhinolophus darlingi , in the context of phenotypic convergence. We used phylogenetic inference to identify and date lineage divergence together with phenotypic comparisons and ecological niche modelling to identify morphological and geographical correlates of those lineages. Our results indicate that R. darlingi is paraphyletic, the eastern and western parts of its distribution forming two distinct non-sister lineages that diverged ~9.7 Mya. We retain R. darlingi for the eastern lineage and argue that the western lineage, currently the sub-species R . d. damarensis , should be elevated to full species status. R. damarensis comprises two lineages that diverged ~5 Mya. Our findings concur with patterns of divergence of other co-distributed taxa which are associated with increased regional aridification between 7-5 Mya suggesting possible vicariant evolution. The morphology and echolocation calls of R. darlingi and R. damarensis are convergent despite occupying different biomes. This suggests that adaptation to similar habitats is not responsible for the convergence. Furthermore, R. darlingi forms part of a clade comprising species that are bigger and echolocate at lower frequencies than R. darlingi , suggesting that biological constraints are unlikely to have influenced the convergence. Instead, the striking similarity in morphology and sensory biology are probably the result of neutral evolutionary processes, resulting in the independent evolution of similar phenotypes

Assessing age related cranial characteristics and morphometrics of the Egyptian rousette (Rousettus aegyptiacus) from central Africa

This study assessed and related quantitative age determination methods based on cranial bone fusion and dental development to linear morphometrics in Rousettus aegyptiacus. Five growth development stages were identified based on cranial suture fusion and degree of second molar tooth eruption. Expressing these growth development stages in measurement size showed a linear growth pattern, with little overlap between smaller (stages 1, 2, and 3) and larger (stages 4 and 5) individuals. Total skull length (TSL), mastoid breadth (MB) and forearm length (FAL) had the highest influence on variation along the first and second principal components, accounting for 93% of variation. Advanced size was confirmed to relate to aging owing to development of cranial suture fusions and dental development. The smallest and largest individuals were significantly (P < 0.05) separated by measurements of TSL, MB and FAL. Meanwhile, some intermediate sized individuals overlapped despite being in different stages of cranial suture development. Species specific reliability in morphological approaches to age determination can be achieved by establishing a baseline reference, which may be directly related to the quantitative cementum growth assessment method.The National Research Foundation, Ditsong National Museum of Natural History small mammals collection and the Defence Threat Reduction Agency and the National United Nations Children’ Fund (UNICEF).https://bioone.org/journals/acta-chiropterologicaMedical VirologyZoology and Entomolog

New records of bat species using Gatkop Cave in the maternal season

Eight bat species were recorded at Gatkop Cave, in the northern part of South Africa in December 2011 (Cloeotis percivali, Hipposideros caffer, Myotis tricolor, Miniopterus natalensis, Nycteris thebaica, Rhinolophus blasii, Rhinolophus smithersi, and Rhinolophus simulator). With the exception of M. natalensis, R. simulator and Myo. tricolor, the other five species were recorded for the first time at Gatkop Cave during this time of the year, when thousands of M. natalensis use the cave as a maternity and nursery roost. Previously it was suggested the large numbers of M. natalensis using Gatkop Cave during the maternal period excluded other bat species. The reason for this recorded change in species roost composition at Gatkop Cave during the maternal period in relation to previous records made from the late 1960s and the mid 1980s is not clear, two possible reasons are the loss of other roosts, or these species were previously present but were not captured as a result of the particular methods used.http://www.degruyter.com/view/j/mamm2017-02-25am2017Centre for Wildlife Managemen

The excreted microbiota of bats : evidence of niche specialisation based on multiple body habitats

Animal-associated microbiotas form complex communities, which play crucial functions for their host, including susceptibility to infections. Despite increasing attention to bats as reservoirs of zoonotic pathogens, their microbiota is poorly documented, especially for samples potentially implicated in pathogen transmission such as urine and saliva. Here, using low-biomass individual samples, we examined the composition and structure of bacterial communities excreted by insectivorous bats, focusing on three body habitats (saliva, urine and faeces). We show that niche specialisation occurs as bacterial community composition was distinct across body habitats with the majority of phylotypes being body habitat specific. Our results suggest that urine harbours more diverse bacterial communities than saliva and faeces and reveal potentially zoonotic bacteria such as Leptospira, Rickettsia, Bartonella and Coxiella in all body habitats. Our study emphasised that, in addition to the traditional use of gut-associated samples such as faeces, both urine and saliva are also of interest because of their diverse microbiota and the potential transmission of pathogenic bacteria. Our results represent a critical baseline for future studies investigating the interactions between microbiota and infection dynamics in bats.This work was supported by the National Research Foundation (NRF) of South Africa [Grant UID 78566 (NRF RISP grant for the ABI3500), UID 91496 and UID 92524], and by the Grant or Cooperative Agreement Number, [1U2GGH001874-01], funded by the Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Preventionor the Department of Health and Human Services. MD’s postdoctoral fellowship is funded by a Capacity Building Grant from the National Research Foundation, South Africa [Grant UID 92524].http://femsec.oxfordjournals.org2018-01-31hb2017Centre for Wildlife ManagementMedical Virolog

Synchronized shift of oral, faecal and urinary microbiotas in bats and natural infection dynamics during seasonal reproduction

Seasonal reproduction is a period of extreme physiological and behavioural changes, yet we know little about how it may affect host microbial communities (i.e. microbiota) and pathogen transmission. Here, we investigated shifts of the bacterial microbiota in saliva, urine and faeces during the seasonal reproduction of bats in South Africa, and test for an interaction in shedding patterns of both bacterial (Leptospira) and viral (adeno- and herpesviruses) agents. Based on a comparative approach in two cave-dwelling bat species and high-throughput sequencing of the 16S rRNA gene, we demonstrated a clear signature in microbiota changes over the reproduction season, consistent across the multiple body habitats investigated, and associated with the sex, age and reproductive condition of bats. We observed in parallel highly dynamic shedding patterns for both bacteria and viruses, but did not find a significant association between viral shedding and bacterial microbiota composition. Indeed, only Leptospira shedding was associated with alterations in both the diversity and composition of the urinary microbiota. These results illustrate how seasonal reproduction in bats substantially affects microbiota composition and infection dynamics, and have broad implications for the understanding of disease ecology in important reservoir hosts, such as bats.In part by the National Research Foundation (NRF) of South Africa: the NRF-DST South African Research Chair held by Prof Markotter, grant no. 98339, as well as grant numbers 92524, 85756 and 91496, and grant UID 78566 (NRF RISP grant for the ABI3500). This research was partially supported by the Cooperative Agreement Number [5 NU2GGH001874-02-00], funded by the Centers for Disease Control and Prevention, USA. M.D.’s postdoctoral fellowship was funded by a Capacity Building Grant from the National Research Foundation, South Africa (grant no. UID 92524).http://rsos.royalsocietypublishing.orgam2018Centre for Wildlife ManagementMammal Research InstituteMedical Virolog

Host conservation through their parasites: molecular surveillance of vector-borne microorganisms in bats using ectoparasitic bat flies

Most vertebrates host a wide variety of haematophagous parasites, which may play an important role in the transmission of vector-borne microorganisms to hosts. Surveillance is usually performed by collecting blood and/or tissue samples from vertebrate hosts. There are multiple methods to obtain samples, which can be stored for decades if properly kept. However, blood sampling is considered an invasive method and may possibly be harmful to the sampled individual. In this study, we investigated the use of ectoparasites as a tool to acquire molecular information about the presence and diversity of infectious microorganism in host populations. We tested the presence of three distinct vector-borne microorganisms in both bat blood and bat flies: Bartonella bacteria, malaria-like Polychromophilus sp. (Apicomplexa), and Trypanosoma sp. (Kinetoplastea). We detected the presence of these microorganisms both in bats and in their bat flies, with the exception of Trypanosoma sp. in South African bat flies. Additionally, we found Bartonella sp. in bat flies from one population in Spain, suggesting its presence in the host population even if not detected in bats. Bartonella and Polychromophilus infection showed the highest prevalence in both bat and bat fly populations. Single, co- and triple infections were also frequently present in both. We highlight the use of haematophagous ectoparasites to study the presence of infectious microorganism in host blood and its use as an alternative, less invasive sampling method