Investigating the production of a particulate plant-produced vaccine candidate against African horse sickness

African horse sickness (AHS) is a non-communicable, infectious disease that affects equids and is mainly prevalent in sub-Saharan Africa. The disease has a major impact on the economy of the equine industry as well as an emotional impact on horse owners. There are nine known serotypes of African horse sickness virus (AHSV), which is spread by Culicoides midges. Currently, a multivalent live attenuated vaccine is the only vaccine licensed for use in South Africa. However, it has the inherent risk of reverting to virulence as well as the possibility of genome segment reassortment between vaccine and outbreak strains. Additionally, it is not DIVA compliant (cannot Differentiate between Infected and Vaccinated Animals). There is therefore a need for a safer and more cost-effective alternative vaccine to protect horses against AHSV. Virus-like particles (VLPs) that display antigens on their surface may be suitable vaccine platforms. One such display particle is the phage AP205 VLP, which is comprised of AP205 coat proteins. To aid antigen display, studies have utilized the SpyTag (ST) - SpyCatcher (SC) or “plug-and-display” system, a novel conjugation system used to display several antigens fused to AP205 VLPs. This study aimed at displaying the neutralizing epitope of AHSV serotype 5, known as the VP2 domain (dom) (873bp), on phage AP205 VLP particles using the SpyTag/SpyCatcher technology. The display particle vaccine candidates were produced in Nicotiana benthamiana plants. Firstly, AHSV 5 VP2dom was expressed by being linked to either the ST or SC peptide at its C-terminus. Recombinant pEAQ-AHSV 5-VP2dom ST and pEAQ-AHSV 5- VP2domSC plasmid constructs were constructed from the full-length pEAQ-AHSV 5-VP2- SpyTag and pEAQ-AHSV 5-VP2-SpyCatcher clones using in-fusion cloning. The ST/SC constructs were transformed into Stellar™ competent E. coli cells and thereafter into Agrobacterium tumefaciens AGL-1 cells. Expression time trials were conducted on plants infiltrated with the recombinant Agrobacterial strains to examine transient AHSV 5- VP2domST/SC small-scale expression. Expression was detected for AHSV 5 VP2domSC but not AHSV 5 VP2domST using guinea pig anti-AHSV 5 and rabbit antiST-AP205 sera. Secondly, the development of a particle display vaccine candidate was investigated by coupling AHSV 5 VP2domSC to plant-expressed ST-AP205 VLPs. Three coupling techniques, namely in vitro coupling of purified products, co-infiltration and co-purification, were deployed to determine the assembly of ST-AP205_AHSV 5 VP2domSC VLPs. In vitro coupling involved carrying out separate infiltrations and purification of pEAQ-STAP205 VLPs and pEAQ-AHSV 5 VP2domSC in plants and thereafter mixing the purified products. For co-infiltration, pEAQ-ST-AP205 VLPs and VP2domSC recombinant cultures were used together to infiltrate plants and the presence of complex formations was determined. During co-purification, the presence of coupled products was analysed following separate infiltration of plants with pEAQ-ST-AP205 and VP2domSC recombinant Agrobacterial strains; the homogenates were then incubated together at different VLP: antigen leaf:weight ratios. From the three coupling techniques, copurification at a 1:1 VLP: antigen ratio was identified as the best coupling approach based on the quality and quantity of particles visualised by electron microscopy. These findings indicate the potential of producing an AHSV vaccine candidate in plants, which is ultimately a safer and cheaper alternative to the currently-produced AHSV vaccine. Moreover, this preliminary data may pave the way for developing a vaccine that provides protection against all nine serotypes of AHSV by displaying VP2domSC for other serotypes on the ST-AP205 display particles

Enhancing student engagement through an institutional blended learning initiative: A case study

Tertiary education institutions grapple with how to better engage students in their learning in high-enrolment, introductory courses. This paper presents a case study that examines a large-scale, faculty-level course redesign project in which this challenge was addressed through the use of blended learning models. The main research question was: Are students in blended formats engaged in their learning differently than those in the traditional formats? The first part of this paper describes the institutional policies, processes, and practices that were established to implement the course redesign project. The second part of the paper focuses on the effectiveness of the project, presenting the results of a longitudinal research study that examined changes in student engagement using the Classroom Survey of Student Engagement (CLASSE). The implications of the longitudinal evaluation and institutional strategy, structure, and support components are examined critically, as well as the project’s impact on students and on the larger university

Evaluating Preceptor Perception of Role Development and Support Initiatives in a Collaborative Bachelor of Science in Nursing Program

Background: Nurse preceptors fulfill a vital role in the success of preceptorship experiences during clinical education of nursing students in their final year of study. Literature does not provide insight on preceptors’ perceptions about whether they feel supported in their knowledge about how to guide undergraduate nursing students in complex clinical learning environments. Objectives: The purpose of this study was to explore Saskatchewan preceptors’ perceptions of their role preparation/development and support, and make recommendations to enhance preceptors’ support to ensure quality learning for preceptored nursing students. Methods: The sample comprised of registered nurses who were current or past preceptors for fourth year undergraduate students. A cross sectional study design was used. Data were gathered through Qualtrics® survey and analyzed to identify statistically significant differences in sub-scales score by demographic subgroups. Results: Significant differences were found between preceptors aged 60 years and older and those aged 30-39 years or 40-49 years on the preparation subscale. In both cases those in \u3e 60 years subgroup scored higher with medium effect sizes. In regard to the years of practice, those with 10-19 years’ experience score higher than those with 5-9 years and 20-29 years, again with medium effect sizes. Conclusion and Recommendations: Gaining understanding of preceptors’ perspectives of what they need to fulfill their role as preceptors is integral to preceptor satisfaction. Enhancing preceptor satisfaction can increase recruitment and retention of preceptors for the future. Additional faculty training and support are needed to ensure faculty and preceptors have a better understanding of their roles. There is need for further development of preceptor manuals to include relevant material for specific clinical areas, a review of evaluation documents, and increased support for younger and least experienced preceptors. Contexte : Les infirmières préceptrices jouent un rôle essentiel dans le succès des expériences de préceptorat durant la formation clinique des étudiantes en dernière année de leurs études en sciences infirmières. La littérature ne fournit aucune information sur les perceptions des préceptrices, à savoir si elles se sentent appuyées lorsqu’elles doivent guider des étudiantes de premier cycle à travers des environnements d’apprentissage clinique complexes. Objectifs : Cette étude visait à explorer les perceptions des infirmières préceptrices en Saskatchewan concernant le développement, la préparation et le soutien en lien avec leur rôle, ainsi qu’à formuler des recommandations pour améliorer le soutien offert aux préceptrices pour assurer un apprentissage de qualité aux étudiantes en sciences infirmières. Méthodes : L’échantillon était composé d’infirmières qui agissaient – ou avaient agi – à titre de préceptrice pour des étudiantes en dernière année de leur programme de premier cycle. Un devis transversal a été utilisé pour cette étude. Les données ont été recueillies au moyen d’un sondage QualtricsMD et analysées dans le but de dégager des différences statistiquement significatives dans le score des sous-échelles pour chaque sous-groupe démographique. Résultats : Sur la sous-échelle de préparation, des différences significatives ont été observées entre les préceptrices âgées de 60 ans et plus et celles âgées de 30 à 39 ou de 40 à 49 ans. Dans les deux cas, celles se trouvant dans le sous-groupe « plus de 60 ans » ont obtenu un meilleur résultat avec des tailles d’effet moyennes. En ce qui concerne les années de pratique, celles ayant de 10 à 19 ans d’expérience ont obtenu un meilleur résultat que celles ayant de 5 à 9 ou de 20 à 29 ans d’expérience. Conclusion et recommandations : Il est essentiel, pour la satisfaction des infirmières préceptrices, de mieux comprendre leurs perspectives en ce qui a trait à leurs besoins pour remplir leur rôle. Le fait d’augmenter la satisfaction des préceptrices peut contribuer favorablement à leur recrutement et leur rétention à l’avenir. Il importe d’accroître la formation et le soutien des membres du corps professoral pour assurer qu’elles ainsi que les infirmières préceptrices comprennent davantage le rôle de ces dernières. Il sera également nécessaire d’actualiser les guides des préceptrices en incluant une documentation pertinente aux domaines cliniques spécifiques, de revoir les documents d’évaluation, et de soutenir davantage les préceptrices plus jeunes et moins expérimentées

Analytical Modeling of a Large Local Area Network - Part I: Internet Traffic Characterization

The goal of both IP network operators and the end users is to get the highest performance from the system for a given cost. This makes Performance a key criterion in the design, procurement, and use of computer and communication systems. In order to address problems associated with performance degradation of operational communicationssystems, over the last decade, traffic engineering techniques have emerged in an attempt to optimize communication systems’ performance and ensure more efficient use of their resources. One of these techniques is analytical modeling. Analytic performance models are an excellent tool for quickly evaluating the performance of operational or new systems. They are also well suited to comparing the performance of several alternative designs. However, analytical models can only be developed once detailed knowledge of characteristics of trafficcarried by a network is available. In Part I of this paper, traffic characterization of traffic carried by the largest Local Area Network (LAN) in Tanzania, University of Dar es Salaam Network (UDSMNET) is carried out. In Part II of this paper, an analytical model based on the Discrete Time Markov Modulated Poisson Process is proposed and validated for performance analysis of IP networks

Policy formulation in Malawi : case of police reform 1995-2000

This paper reviews the process of policy formulation in Malawi with particular reference to police reform between 1995 and 2000. After a long period of one party government, Malawi from 1994 made the transition to a multiparty parliamentary democracy. The Malawi Police is an important institution in the new regime. Within the frameworks of interest group theory and stakeholder theory the paper explores the way in which various interests influenced the reform of the police organization and management from 1995 to 2000. Reviews were undertaken of the literature on the policy process and the scholarly writing on interest group and stakeholder theory. Field research was carried out in the public documentation available in Malawi and by face to face interviews with senior officials and other participants in the reform process. The findings confirmed the utility of both interest group and stakeholder theory in explaining how public policies are formulated

Dissemination of Agro-based Information by Telecentres among Selected Rural Farmers in Tanzania with a focus on Moshi Rural District, Kilimanjaro Region

The study assessed the role of Telecentres in the dissemination of agro-based information among selected farmers in rural areas of Tanzania. A cross-sectional study design was conducted in Moshi Rural District, in Kilimanjaro Region, Tanzania. A total of 442 rural farmers aged 21-60 years were randomly selected as study respondents. Questionnaires were used to collect data from respondents. The study found that 205 (55%) respondents were not aware of the existence and services offered among Telecentres, whereas only 12 (7%) respondents reported visiting Telecentres once per day, and 70 (41%) once per year. A total of 140 respondents selected computer services including internet, printing, and scanning to be available among Telecentres. 162 respondents recommended promotion and marketing strategies to enhance the usage of Telecentres among rural farmers was recommended by 162 respondents, while 200 requested agro-based information on crop diseases and pest problems. Inadequate agro-based information in the local language (Swahili) was reported among the challenges hindering the usage of Telecentres among 180 respondents. We recommend the government to exploit the potential of Telecentres in the dissemination of agro-based information among farmers and societies at large

A Review of Characterization Approaches for Smallholder Farmers: Towards Predictive Farm Typologies.

This research article published by Hindawi, 2019Characterization of smallholder farmers has been conducted in various researches by using machine learning algorithms, participatory and expert-based methods. All approaches used end up with the development of some subgroups known as farm typologies. The main purpose of this paper is to highlight the main approaches used to characterize smallholder farmers, presenting the pros and cons of the approaches. By understanding the nature and key advantages of the reviewed approaches, the paper recommends a hybrid approach towards having predictive farm typologies. Search of relevant research articles published between 2007 and 2018 was done on ScienceDirect and Google Scholar. By using a generated search query, 20 research articles related to characterization of smallholder farmers were retained. Cluster-based algorithms appeared to be the mostly used in characterizing smallholder farmers. However, being highly unpredictable and inconsistent, use of clustering methods calls in for a discussion on how well the developed farm typologies can be used to predict future trends of the farmers. A thorough discussion is presented and recommends use of supervised models to validate unsupervised models. In order to achieve predictive farm typologies, three stages in characterization are recommended as tested in smallholder dairy farmers datasets: (a) develop farm types from a comparative analysis of more than two unsupervised learning algorithms by using training models, (b) assess the training models' robustness in predicting farm types for a testing dataset, and (c) assess the predictive power of the developed farm types from each algorithm by predicting the trend of several response variables