Origins of the amphiploid species Brassica napus L. investigated by chloroplast and nuclear molecular markers

Background: The amphiploid species Brassica napus (oilseed rape, Canola) is a globally important oil crop yielding food, biofuels and industrial compounds such as lubricants and surfactants. Identification of the likely ancestors of each of the two genomes (designated A and C) found in B. napus would facilitate incorporation of novel alleles from the wider Brassica genepool in oilseed rape crop genetic improvement programmes. Knowledge of the closest extant relatives of the genotypes involved in the initial formation of B. napus would also allow further investigation of the genetic factors required for the formation of a stable amphiploid and permit the more efficient creation of fully fertile re-synthesised B. napus. We have used a combination of chloroplast and nuclear genetic markers to investigate the closest extant relatives of the original maternal progenitors of B. napus. This was based on a comprehensive sampling of the relevant genepools, including 83 accessions of A genome B. rapa L. (both wild and cultivated types), 94 accessions of B. napus and 181 accessions of C genome wild and cultivated B. oleracea L. and related species. Results: Three chloroplast haplotypes occurred in B. napus. The most prevalent haplotype (found in 79% of accessions) was not present within the C genome accessions but was found at low frequencies in B. rapa. Chloroplast haplotypes characteristic of B. napus were found in a small number of wild and weedy B. rapa populations, and also in two accessions of cultivated B. rapa 'brocoletto'. Whilst introgression of the B. napus chloroplast type in the wild and weedy B. rapa populations has been proposed by other studies, the presence of this haplotype within the two brocoletto accessions is unexplained. Conclusions: The distribution of chloroplast haplotypes eliminates any of the C genome species as being the maternal ancestor of the majority of the B. napus accessions. The presence of multiple chloroplast haplotypes in B. napus and B. rapa accessions was not correlated with nuclear genetic diversity as determined by AFLPs, indicating that such accessions do not represent recent hybrids. Whilst some chloroplast diversity observed within B. napus can be explained by introgression from inter-specific crosses made during crop improvement programmes, there is evidence that the original hybridisation event resulting in to B. napus occurred on more than one occasion, and involved different maternal genotypes

Porcine reproductive and respiratory syndrome virus (PRRSV) in GB pig herds : farm characteristics associated with heterogeneity in seroprevalence

Background: The between- and within-herd variability of porcine reproductive and respiratory syndrome virus (PRRSV) antibodies were investigated in a cross-sectional study of 103 British pig herds conducted 2003–2004. Fifty pigs from each farm were tested for anti-PRRSV antibodies using ELISA. A binomial logistic model was used to investigate management risks for farms with and without pigs with PRRSV antibodies and multilevel statistical models were used to investigate variability in pigs' log ELISA IRPC (relative index × 100) in positive herds. Results: Thirty-five herds (34.0%) were seronegative, 41 (39.8%) were seropositive and 27 (26.2%) were vaccinated. Herds were more likely to be seronegative if they had < 250 sows (OR 3.86 (95% CI 1.46, 10.19)) and if the nearest pig herd was ≥ 2 miles away (OR 3.42 (95% CI 1.29, 9.12)). The mean log IRPC in seropositive herds was 3.02 (range, 0.83 – 5.58). Sixteen seropositive herds had only seropositive adult pigs. In these herds, pigs had -0.06 (95% CI -0.10, -0.01) lower log IRPC for every mile increase in distance to the nearest pig unit, and -0.56 (95% CI -1.02, -0.10) lower log IRPC when quarantine facilities were present. For 25 herds with seropositive young stock and adults, lower log IRPC were associated with isolating purchased stock for ≥ 6 days (coefficient - 0.46, 95% CI -0.81, -0.11), requesting ≥ 48 hours 'pig-free time' from humans (coefficient -0.44, 95% CI -0.79, -0.10) and purchasing gilts (coefficient -0.61, 95% CI -0.92, -0.29). Conclusion: These patterns are consistent with PRRSV failing to persist indefinitely on some infected farms, with fadeout more likely in smaller herds with little/no reintroduction of infectious stock. Persistence of infection may be associated with large herds in pig-dense regions with repeated reintroduction

Transitions from Undergraduate to Taught Postgraduate Study: Emotion, Integration and Ambiguity

The notion and terminology of ‘transition(s)’ have long dominated discussions of pathways from youth to adulthood and have increasingly come to characterise the educational journeys people make, with a strong emphasis on the shift from schooling to undergraduate study. However, the transitional experiences of postgraduate students have been significantly overlooked with powerful presumptions around postgraduate students being educational ‘experts’ and ‘naturals’ obscuring the often highly challenging nature of their transitions. The lack of literature in this field is most pronounced around the taught postgraduate (PGT) population, about whom the least is known. This is due in part to ambiguousness around PGT study itself (Glazer-Raymo, 2005) which falls between the clearly-defined undergraduate and doctoral degrees, and has been declared as the “forgotten sector” (Millward, 2015) of higher education.  This paper addresses this gap in understanding by synthesising the available literature on PGT transitions, and on postgraduate transitions more generally, alongside qualitative focus group data from a small-scale project with Masters students and supervisors conducted at a Scottish university. It finds that transitions to PGT education are complex, emotional and challenging for most students, and highlights some institutional practices that can isolate, confuse and hinder the progress of Masters students.  Thus, the paper argues that, contrary to conventional assumptions, transitions from undergraduate to PGT education are not inevitably straightforward and can be characterised, at least initially, by anxiety, self-doubt and disorientation. Key challenges for Masters students do not necessarily relate to the higher learning materials, but the lack of clarity around what PGT level study entails and the limited opportunities for integration and sense of belonging. Greater clarity of expectations and earlier feedback, alongside peer support, can help to smooth transitions to postgraduate study. The paper also highlights the particularly difficult transitions of students unfamiliar to the university and identifies challenges specific to funded and non-funded students

The percutaneous absorption of soman in a damaged skin porcine model and the evaluation of WoundStat™ as a topical decontaminant

PURPOSE: The aim of this study was to evaluate a candidate haemostat (WoundStat™), down-selected from previous in vitro studies, for efficacy as a potential skin decontaminant against the chemical warfare agent pinacoyl methylfluorophosphonate (Soman, GD) using an in vivo pig model. MATERIALS AND METHODS: An area of approximately 3 cm2 was dermatomed from the dorsal ear skin to a nominal depth of 100 µm. A discrete droplet of 14C-GD (300 µg kg-1) was applied directly onto the surface of the damaged skin at the centre of the dosing site. Animals assigned to the treatment group were given a 2 g application of WoundStat™ 30 s after GD challenge. The decontamination efficacy of WoundStat™ against GD was measured by the direct quantification of the distribution of 14C-GD, as well as routine determination of whole blood cholinesterase and physiological measurements. RESULTS: WoundStat™ sequestered approximately 70% of the applied 14C-GD. Internal radiolabel recovery from treated animals was approximately 1% of the initially applied dose. Whole blood cholinesterase levels decreased to less than 10% of the original value by 15 min post WoundStat™ treatment and gradually decreased until the onset of apnoea or until euthanasia. All treated animals showed signs of GD intoxication that could be grouped into early (mastication, fasciculations and tremor), intermediate (miosis, salivation and nasal secretions) and late onset (lacrimation, body spasm and apnoea) effects. Two of the six WoundStat™ treated animals survived the study duration. CONCLUSIONS: The current study has shown that the use of WoundStat™ as a decontaminant on damaged pig ear skin was unable to fully protect against GD toxicity. Importantly, the findings indicate that the use of WoundStat™ in GD contaminated wounds would not exacerbate GD toxicity. These data suggest that absorbent haemostatic products may offer some limited functionality as wound decontaminants.Peer reviewedFinal Accepted Versio

Dissecting the role of Complex I ROS production via forward and reverse electron transport in the brain of Drosophila melanogaster

Ph. D. ThesesThe dual nature of reactive oxygen species (ROS) is a widely recognised paradox. For many years, mitochondrial ROS were characterised as the main cause of ageing and chronic ROS production was documented in many age-related diseases. In contrast, recent studies have described ROS as signalling molecules essential for maintaining cellular homeostasis. Further experimentation has revealed that the extent of ROS production, as well as the location, can be important in determining the behaviour of ROS. The best example is the process known as Reverse Electron Transport (RET). RET is associated with a large increase in site-specific ROS production at CI and is responsible for stimulating key signalling pathways that control stress adaptation and cellular fate. Additionally, the expression of the alternative NADH dehydrogenase, Ndi1, which promotes ROS-RET, leads to extension of lifespan in Drosophila melanogaster. Exploring ROS-RET signalling may be instrumental in understanding the role of ROS in health and disease. In the following chapters, I investigate the mechanisms behind ROS-RET. I use ex vivo ROS measurements in the brain of Drosophila melanogaster to demonstrate that ROS-RET occurs under physiological conditions when flies are exposed to heat stress. I describe in detail how manipulation of the electron transport chain affects the occurrence of ROS-RET. My results reveal that the entry of electrons through CI and CII is essential for ROS-RET to occur. However, blocking the exit of electrons (CIII-CIV) increases ROS production but not via ROS-RET. Finally I have performed a genome-wide RNAi screen, taking advantage of the alternative oxidase (AOX) that supresses ROS-RET, where I have found new candidate genes responsible for regulating mitochondrial ROS levels. In summary, I provide evidence of how ROS-RET can be regulated in vivo including its physiological stimulation, factors essential for its generation and new genes involved in its regulation

Allogeneic CAR-T cells: more than ease of access?

Patient derived anti-CD19 chimeric antigen receptor-T (CAR-T) cells are a powerful tool in achieving a complete remission in a range of B-cell malignancies, most notably B-acute lymphoblastic leukaemia (B-ALL) and diffuse large B-cell lymphoma (DLBCL). However, there are limitations, including inability to manufacture CAR-T cells from the patient’s own T cells, disease progression and death prior to return of engineered cells. T cell dysfunction is known to occur in cancer patients, and several groups have recently described differences in CAR-T cells generated from chronic lymphocytic leukaemia (CLL) patients compared with those from a healthy donor. This is thought to contribute to the low response rate in this disease group. Healthy donor, gene-edited CAR-T cells which do not require human leucocyte antigen (HLA) matching have the potential to provide an ‘off the shelf’ product, overcoming the manufacturing difficulties of producing CAR-T cells for each individual patient. They may also provide a more functional, potent product for malignancies such as CLL, where T cell dysfunction is common and frequently cannot be fully reversed during the manufacturing process. Here we review the potential benefits and obstacles for healthy donor, allogeneic CAR-T cells

The experiences of students with mental health difficulties at an Australian regional university: overcoming barriers to successful educational and employment outcomes

Educational achievement is consistently linked to better employment outcomes for individuals, but navigating through higher education can be particularly challenging for regional, rural, and remote students. Some individuals face additional difficulties linked to personal disability, and a particularly vulnerable group are those individuals with an identified mental health issue. Flexibility in study options can enable many students to access higher education, with distance education, a choice for many living regionally, providing both opportunities and challenges for study. The research presented here is part of a project funded by the National Centre for Student Equity in Higher Education (NCSEHE), which explored the lived experiences of individuals with a disability at a regional Australian university. The overall focus for the research was to understand individual resilience and what enables some students with mental health problems to be successful in their educational achievement. The present research draws on findings from semi-structured interviews with nine individuals identifying with mental health difficulties. Subsequent analysis followed Braun and Clarke’s (2006) approach to thematic analysis. The key themes identified were those of disclosure and the decision to register or not with disability services; interactions with ‘faculty’; and strategies for positive educational engagement. We concluded that a major challenge in the higher education sector relates to building disability support services that are responsive to the needs of students with a psychological disability. The findings from this study advance knowledge in understanding what strategies a successful student with a mental health issue draws upon in order to succeed, and what implications this may have for the shaping of student support services

Community College Instructional Support of Nontraditional Students Using Technology

Nontraditional students often enroll at institutions of higher learning without the technology skills needed to complete coursework and achieve academic success. The problem at a small community college in the Southern United States is that instructors are providing limited support for nontraditional students using technology, which may leave students ill-prepared to complete coursework. The purpose of this qualitative study was to examine instructional support of nontraditional students using technology to complete coursework and to make recommendations to improve instructional support of students. Knowles’s adult learning theory, Daloz’s mentoring theory, and Siemens’s connectivist theory provided the framework for the study. Research questions addressed how community college instructors support nontraditional students using technology in coursework and how such support aids academic success. Semistructured interviews with nine purposively selected instructors, the Policy and Procedure Manual for Distance and Electronic Learning, and Student Success Center documents were examined through coding and thematic analysis. Participants indicated nontraditional students lacked basic computer skills and internet access and were unfamiliar with the college’s learning management system. Document analysis revealed the college has a support system for both nontraditional students and instructors using technology. Participants recommended providing resources, individual help, and guidance to nontraditional students using technology, while documents suggested that students and instructors utilize the support system at the college. Study results presented in a position paper afforded an opportunity for social change by improving instructional support of nontraditional students in using technology to complete coursework and achieve academic success

Burnout among primary healthcare workers during implementation of integrated mental healthcare in rural Ethiopia: a cohort study

Background The short-term course of burnout in healthcare workers in low- and middle-income countries has undergone limited evaluation. The aim of this study was to assess the short-term outcome of burnout symptoms in the context of implementation of a new mental health programme in a rural African district. Methods We followed up 145 primary healthcare workers (HCWs) working in 66 rural primary healthcare (PHC) facilities in Southern Ethiopia, where a new integrated mental health service was being implemented. Burnout was assessed at baseline, i.e. when the new service was being introduced, and after 6 months. Data were collected through self-administered questionnaires, including the Maslach Burnout Inventory (MBI) and instruments measuring professional satisfaction and psychosocial factors. Generalised estimating equations (GEE) were used to assess the association between change in the core dimension of burnout (emotional exhaustion) and relevant work-related and psychosocial factors. Results A total of 136 (93.8%) of HCWs completed and returned their questionnaires at 6 months. There was a non-significant reduction in the burnout level between the two time points. In GEE regression models, high depression symptom scores (adjusted mean difference (aMD) 0.56, 95% CI 0.29, 0.83, p < 0.01), experiencing two or more stressful life events (aMD 1.37, 95% CI 0.06, 2.14, p < 0.01), being a community health extension worker vs. facility-based HCW (aMD 5.80, 95% CI 3.21, 8.38, p < 0.01), perceived job insecurity (aMD 0.73, 95% CI 0.08, 1.38, p = 0.03) and older age (aMD 0.36, 95% CI 0.09, 0.63, p = 0.01) were significantly associated with higher levels of emotional exhaustion longitudinally. Conclusion In the short-term, there was no significant change in the level of burnout in the context of adding mental healthcare to the workload of HCWs. However, longer term and larger scale studies are required to substantiate this. This evidence can serve as baseline information for an intervention development to enhance wellbeing and reduce burnout