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Diagnosis and control of foot rot pathogens of wheat
Foot rot disease of wheat is caused by the pathogens Fusarium culmorum, F. avenaceum and Microdochium nivale. Symptoms of foot rot are a general browning of the stem base and leaf sheath. There is a discrepancy between the ability of fungicides to control these pathogens in vivo and in vitro, and no relationship between disease symptom severity and yield loss has been established in wheat. The identification of the causal agents of foot rot disease is not possible from examination of disease symptoms alone.
This work showed that the azole fungicides flusilazole and prochloraz inhibited the germination of conidia and mycelial growth of F. culmorum, F. avenaceum and M. nivale in vitro to a varying extent. However, no consistent control of these pathogens in wheat was observed in the field using the same fungicides. Further studies employing a semicontrolled outdoor experiment showed a relationship between density and timing of inoculum application, disease symptom severity and yield loss in wheat artificially inoculated with F. culmorum and M. nivale.
Molecular marker systems were used to address the problem of pathogen detection and identification. A Random Amplified Polymorphic DNA (RAPD) assay was developed to differentiate F. culmorum, F. avenaceum and two types ofM. nivale (M. nivale var.nivale and M. nivale var.majus in vitro. Selected RAPD products were cloned and sequenced and species specific primers constructed from this sequence information. These primers were used in the polymerase chain reaction (peR) and were shown to detect the pathogens in host tissue. This technique was adapted by addition of a competitor fragment to the peR reaction resulting in a quantifiable competitive peR assay. Using this method the fungal biomass of each pathogen present in the host tissue could be estimated. The development of these techniques for the identification, detection and quantification of F. culmorum, F. avenaceum, M. nivale var.nivale and M. nivale var. majus in plant tissue will allow more extensive studies of the epidemiology of these species, the competition between species and the effect of fungicides on these pathogens can be carried out
Community as a Sustaining Force: Strategies for Online Scholarly Support
This paper discusses the ways that community connections serve to sustain and support scholarly growth, retention, and success, particularly in longer-term online contexts. These strategies are seen through the reflective experience of a faculty mentor and two recent graduates who co-developed community support strategies that help doctoral students stay motivated, connected, and succeed over many years of what might otherwise be a long, individual, and lonely journeyâparticularly when undertaken online. A matrix of strategies, apps, and online tools emerged from this process and is offered for consideration
Trainee teachers' beliefs about, and attitudes towards, gay and lesbian learners : a correlational study.
M. Soc. Sc. University of KwaZulu-Natal, Durban 2014.This studyâs predominant aim was to investigate whether a correlation existed between the knowledge about homosexuality, and the attitudes towards homosexuals, of trainee teachers in KwaZulu-Natal. The scarcity of empirical data guiding homophobic intervention programs in teacher training colleges, as well as the importance of such research, led to the motivation behind this study. This study was therefore based upon the following objectives; to explore whether low levels of knowledge about homosexuality was related to high levels of homophobic attitudes, to test whether the previous attendance on a course in which homosexuality was included in the syllabus resulted in significantly higher levels of knowledge and lower levels of homophobic attitudes, and finally to make preliminary recommendations for intervention programs based on the findings of this study. This research used quantitative methodology with a correlational research design to achieve its objectives. A sample of 106 first year students at a teacher training college in KwaZulu-Natal were given questionnaires that comprised of 2 psychometric scales; Knowledge about Homosexuality Questionnaire (Harris, Nightengale, & Owen, 1995) and The Modern Homophobia Scale (Raja & Stokes, 1998). Biographic information as well as scores for each participant was obtained indicating their knowledge about homosexuality and attitudes towards gay men, lesbians and homosexuals in general. Findings of this study indicate that lower levels of knowledge about homosexuality are related to higher levels of homophobia. It was also found that previous attendance on a course in which homosexuality was included in the syllabus did not result in significant differences in the trainee teachersâ knowledge about, or attitudes towards homosexuality. Supplementary findings of this study indicated that male trainee teachersâ attitudes towards gay men are significantly more negative when compared to female trainee teachers. Furthermore, knowledge about homosexuality scores for male trainee teachers were significantly lower when compared to female trainee teachers. Another supplementary finding suggested that having close contact with a homosexual individual resulted in significantly lower levels of homophobic attitudes in trainee teachers when compared to those who did not. Preliminary recommendations for homophobia-intervention courses that were made based on this studyâs findings included the need to address the low levels of knowledge about homosexuality, the need to expand the scope of the course content to include broader issues of sexuality, specifically gender roles, and lastly to include contact with homosexual individuals while on the course
'It is just the way it was in the past before I went to test': a qualitative study to explore responses to HIV prevention counselling in rural Tanzania.
BACKGROUND: Voluntary counselling and testing (VCT) for HIV first evolved in Western settings, with one aim being to promote behaviours which lower the risk of onward transmission or acquisition of HIV. However, although quantitative studies have shown that the impact of VCT on sexual behaviour change has been limited in African settings, there is a lack of qualitative research exploring perceptions of HIV prevention counselling messages, particularly among clients testing HIV-negative. We conducted a qualitative study to explore healthcare worker, community and both HIV-negative and HIV-positive clients' perceptions of HIV prevention counselling messages in rural Tanzania. METHODS: This study was carried out within the context of an ongoing community HIV cohort study in Kisesa, northwest Tanzania. Nine group sessions incorporating participatory learning and action (PLA) activities were conducted in order to gain general community perspectives of HIV testing and counselling (HTC) services. Thirty in-depth interviews (IDIs) with HIV-negative and HIV-positive service users explored individual perceptions of HIV prevention counselling messages, while five IDIs were carried out with nurses or counsellors offering HTC in order to explore provider perspectives. RESULTS: Two key themes revolving around socio-cultural and contextual factors emerged in understanding responses to HIV prevention counselling messages. The first included constraints to client-counsellor interactions, which were impeded as a result of difficulties discussing private sexual behaviours during counselling sessions, a hierarchical relationship between healthcare providers and clients, insufficient levels of training and support for counsellors, and client concerns about confidentiality. The second theme related to imbalanced gender-power dynamics, which constrained the extent to which women felt able to control their HIV-related risk. CONCLUSION: Within the broader social context of a rural African setting, HIV prevention counselling based on a Western model of individual-level agency seems unlikely to make a significant contribution to sexual behaviour change until there is greater recognition by counsellors of the ways in which power dynamics within many relationships influence behaviour change. More culturally relevant counselling strategies and messages and infrastructural improvements such as additional training for counsellors and counselling rooms which ensure privacy and confidentiality, may lead to better outcomes in terms of sexual risk reduction
Characterisation of acute respiratory infections at a United Kingdom paediatric teaching hospital: observational study assessing the impact of influenza A (2009 pdmH1N1) on predominant viral pathogens
Background According to the World Health Organisation, influenza A (2009 pdmH1N1) has moved into the post-pandemic phase, but there were still high numbers of infections occurring in the United Kingdom in 2010-11. It is therefore important to examine the burden of acute respiratory infections at a large childrenâs hospital to determine pathogen prevalence, occurrence of co-infection, prevalence of co-morbidities and diagnostic yield of sampling methods. Methods This was a retrospective study of respiratory virus aetiology in acute admissions to a paediatric teaching hospital in the North West of England between 1st April 2010 and 31st March 2011. Respiratory samples were analysed either with a rapid RSV test if the patient had symptoms suggestive of bronchiolitis, followed by multiplex PCR testing for ten respiratory viruses, or with multiplex PCR testing alone if the patient had suspected other ARI. Patient demographics and data regarding severity of illness, presence of co-morbidities and respiratory virus sampling method were retrieved from case notes. Results 645 patients were admitted during the study period. 82/645 (12.7%) patients were positive for 2009 pdmH1N1, of whom 24 (29.2%) required PICU admission, with 7.3% mortality rate. Viral co-infection occurred in 48/645 (7.4%) patients and was not associated with more severe disease. Co-morbidities were present more frequently in older children, but there was no significant difference in prevalence of co-morbidity between 2009 pdmH1N1 patients and those with other ARI. NPA samples had the highest diagnostic yield with 192/210 (91.4%) samples yielding an organism. Conclusions Influenza A (2009 pdmH1N1) is an ongoing cause of occasionally severe disease affecting both healthy children and those with co-morbidities. Surveillance of viral pathogens provides valuable information on patterns of disease
The discrete roles of individual FOXO transcription factor family members in B-cell malignancies
Forkhead box (FOX) class O (FOXO) proteins are a dynamic family of transcription factors composed of four family members: FOXO1, FOXO3, FOXO4 and FOXO6. As context-dependent transcriptional activators and repressors, the FOXO family regulates diverse cellular processes including cell cycle arrest, apoptosis, metabolism, longevity and cell fate determination. A central pathway responsible for negative regulation of FOXO activity is the phosphatidylinositol-3-kinase (PI3K)-AKT signalling pathway, enabling cell survival and proliferation. FOXO family members can be further regulated by distinct kinases, both positively (e.g., JNK, AMPK) and negatively (e.g., ERK-MAPK, CDK2), with additional post-translational modifications further impacting on FOXO activity. Evidence has suggested that FOXOs behave as âbona fideâ tumour suppressors, through transcriptional programmes regulating several cellular behaviours including cell cycle arrest and apoptosis. However, an alternative paradigm has emerged which indicates that FOXOs operate as mediators of cellular homeostasis and/or resistance in both ânormalâ and pathophysiological scenarios. Distinct FOXO family members fulfil discrete roles during normal B cell maturation and function, and it is now clear that FOXOs are aberrantly expressed and mutated in discrete B-cell malignancies. While active FOXO function is generally associated with disease suppression in chronic lymphocytic leukemia for example, FOXO expression is associated with disease progression in diffuse large B cell lymphoma, an observation also seen in other cancers. The opposing functions of the FOXO family drives the debate about the circumstances in which FOXOs favour or hinder disease progression, and whether targeting FOXO-mediated processes would be effective in the treatment of B-cell malignancies. Here, we discuss the disparate roles of FOXO family members in B lineage cells, the regulatory events that influence FOXO function focusing mainly on post-translational modifications, and consider the potential for future development of therapies that target FOXO activity
Rape and respectability: ideas about sexual violence and social class
Women on low incomes are disproportionately represented among sexual violence survivors, yet feminist research on this topic has paid very little attention to social class. This article blends recent research on class, gender and sexuality with what we know about sexual violence. It is argued that there is a need to engage with classed distinctions between women in terms of contexts for and experiences of sexual violence, and to look at interactions between pejorative constructions of working-class sexualities and how complainants and defendants are perceived and treated. The classed division between the sexual and the feminine, drawn via the notion of respectability, is applied to these issues. This piece is intended to catalyse further research and debate, and raises a number of questions for future work on sexual violence and social class
Research is âa step into the unknownâ: an exploration of pharmacistsâ perceptions of factors impacting on research participation in the NHS
Objective This study explored National Health Service (NHS) pharmacists’ perceptions and experiences of pharmacist-led research in the workplace. Design Semistructured, face-to-face discussions continued until distinct clusters of opinion characteristics formed. Verbatim transcripts of audio-recordings were subjected to framework analysis. Setting Interviews were carried out with 54 pharmacists with diverse backgrounds and roles from general practices and secondary care in the UK's largest health authority. Results The purpose and potential of health services research (HSR) was understood and acknowledged to be worthwhile by participants, but a combination of individual and system-related themes tended to make participation difficult, except when this was part of formal postgraduate education leading to a qualification. Lack of prioritisation was routinely cited as the greatest barrier, with motivation, confidence and competence as additional impediments. System-related themes included lack of practical support and pharmacy professional issues. A minority of highly motivated individuals managed to embed research participation into routine activity. Conclusions Most pharmacists realised the desirability and necessity of research to underpin pharmacy service expansion, but a combination of individual and professional level changes is needed to increase activity. Our findings provide a starting point for better understanding the mindset of hospital-based and general practice-based pharmacists towards research, as well as their perceived barriers and supports
New functional families (FunFams) in CATH to improve the mapping of conserved functional sites to 3D structures.
CATH version 3.5 (Class, Architecture, Topology, Homology, available at http://www.cathdb.info/) contains 173 536 domains, 2626 homologous superfamilies and 1313 fold groups. When focusing on structural genomics (SG) structures, we observe that the number of new folds for CATH v3.5 is slightly less than for previous releases, and this observation suggests that we may now know the majority of folds that are easily accessible to structure determination. We have improved the accuracy of our functional family (FunFams) sub-classification method and the CATH sequence domain search facility has been extended to provide FunFam annotations for each domain. The CATH website has been redesigned. We have improved the display of functional data and of conserved sequence features associated with FunFams within each CATH superfamily
CATH: comprehensive structural and functional annotations for genome sequences.
The latest version of the CATH-Gene3D protein structure classification database (4.0, http://www.cathdb.info) provides annotations for over 235,000 protein domain structures and includes 25 million domain predictions. This article provides an update on the major developments in the 2 years since the last publication in this journal including: significant improvements to the predictive power of our functional families (FunFams); the release of our 'current' putative domain assignments (CATH-B); a new, strictly non-redundant data set of CATH domains suitable for homology benchmarking experiments (CATH-40) and a number of improvements to the web pages
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