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Studies on paramphistomes infecting goats and sheep from Gwanda District in Zimbabwe
No full textParamphistomes were collected from 3000 goats and 1000 sheep from various localities in Gwanda district in Matabeleland South Province Zimbabwe. On slaughter their stomachs,rumens and reticulum were cut open and their inner walls were examined for attached paramphistomes. Identifications were based on the morphological structures and measurements of diagnostic features from flattened and median sagittal sections. Analysis of the structures of the acetabulum, pharynx and genital atrium revealed the following parasites in the area, Calicophoron microbothrium, Calicophoron clavula and Ceylonocotyle dicranocoelium. The degree of tissue damage on the host was generally slight except for cases where Ceylonocotyle dicranocoelium was involved. The percentage of goats infected with paramphistomes was 2% while in sheep it was 6%. The number of parasites in goats ranged from 5 to 500 while in sheep the range was 5 to 1000
Simulations of a parallel-plate electrorheological (ER) actuator as a robotic drive
No full textPublished in the proceedings of the 25th International Conference of CAD/CAM, Robotics & Factories of the Future,13-16 July 2010 Pretoria,South AfricaThis paper presents, briefly, results of tests conducted on a parallel-plate electrorheological (ER) clutch for use as an actuator for small-to-medium size robots, and simulations of scenarios of the ER actuator driving simple model scale robotic joints. An ER clutch is a device that uses a special typeof fluids known as ER fluids or suspensions as a coupling medium. These fluids are normally Newtonian, but become non-Newtonian and subsequently solid when subjected to electric fields of sufficient strength (of the order of 103 V(mm)-1). The ER effect has been shown to have an inverse dependence on fluid temperature and thus it is necessary to provide cooling for the device in order to achieve best performance. The challenges in the design are the large operational electric fields and the desire or need to keep the mass of the moving robotic links to a minimum. The output torque from the device is relatively low, but it is thought that coupling the device?s output to a gearbox with a high transmission ratio can achieve good results
Cleaner Production Techniques for Mitigation of Tannery Waste: Case Study ABC
No full textProceedings of the 4th Engineers Without Borders International Conference, Victoria Falls, Zimbabwe, 10th ? 14th November 2010.The need for sustainable use of resources has come to the fore in recent years as the globe has realised that there are finite resources available on the earth that must also be utilised by future generations. It is within this scenario that manufacturing has evolved to incorporate environmentally friendly practices and so called ?green? technology. Smaller firms especially in
developing countries have however not been exposed to these new technologies making them
liable for legislative penalties and less efficient than they otherwise could be. This paper presents a tool that will enhance the ability of a medium scale tannery to manufacture in line with current international environmental standards through the implementation of an environmental management system. The paper focuses on the application of cleaner production principles in the mitigation of identified environmental risks and the ensuing development of alternative processing strategies that will both increase efficiency as well as reduce the
environmental impact of the leather tanning operations of the given firm
?Visible Hectares, Vanishing Livelihoods?: A case of the Fast Track Land Reform and Resettlement Programme in southern Matabeleland - Zimbabwe
No full textThesis submitted in fulfilment of the requirement for the Degree of Doctor of Social Sciences (Development Studies) Faculty of Social Science and Humanities University of Fort Hare.Land reform has been going on in Zimbabwe since the state attained independence from Britain in 1980 as a way of enhancing agrarian livelihoods for the formerly marginalized people. This study argues that, the Land Reform Programme in Southern Matabeleland rather than enhancing agrarian livelihoods, well established livelihoods have actually been drastically reduced. This has been exacerbated by the state programme of land re-distribution that prescribes a ?one size fits all? model. Yet this is contrary to the thinking in development discourse that equitable land distribution increases rural livelihoods. As a way of gathering data this study utilized ethnography and case study methodologies. I spent two years interacting and interviewing purposively selected new resettles, communal residents, migrant workers and gold panners in this region. Results from this study confirm that, land reform has greatly reduced livelihoods, particularly agrarian livelihoods. Also, this research has found out that, the majority of residents now depend on off-farm livelihoods such as gold panning and migration to neighbouring South Africa. This thesis therefore concludes that, despite a massive expropriation of former commercial farms, people of Southern Matabeleland have not benefitted much as the village settlements (A1) and the small size farms (A2) have not received support from this live-stocking community. People in this region pin their hopes on livestock rearing to sustain their livelihoods and this study therefore recommends that, any agrarian transformation programmes should address the issues that promote livestock rearing
A Preliminary Study on Causes of Non Retention of Masendu Ward Girls at Secondary School
No full textThis case study is a preliminary attempt to identify possible factors that might contribute to poor retention and progression of a girl-child in Secondary School education in Masendu Area. The study was conducted using school leavers from Masendu ward, in the Bulilima district of Zimbabwe. The results presented in this study were collected from a workshop attended by 13 female and 2 male school leavers from Masendu Ward and 10 female students from the National University of Science and Technology. Questionnaires and focus group discussions were used as instruments for collecting data. The results serve as a preliminary to the pilot study conducted at the Mangwe district in Plumtree. A paper on the study is to follow. From the data collected in the workshop, twelve major problems were identified which most participants viewed as the key contributors to the poor retention and progression of a girl child in secondary school education. The problems identified included just to mention a few: early pregnancies, lack of finance, lack of moral support and protection from unruly
characters on the way , after school sporting activities which cause the children to leave school late, leaving school to seek job in neighbouring countries. Some of the suggestions of improving the retention on a girl ?child at secondary school included the need to educate school girls on importance of abstinence, community to seek sponsorships, need for intervention from the community at large to safeguard the education of all children irrespective of gender, provision of cheap accommodation at school or at villages near school, sport activities could be scheduled one morning of a chosen day during the week to enable the students to leave school early and get home before it of dark. Lessons for that day could be covered by extending the other remain 4 days by a lesson or two, career guidance that emphases the need of education for a long lasting career
The Usefulness of One-Wire Networks
No full textThe class of networks generally known as ?one-wire ? is introduced and the salient points of architecture, collision handing and protocol are described. The suitability of these networks for communication between microcontrollers is explained and three methods of interfacing are outlined. Such systems are illustrated by reference to the CAN network, the Dallas iButton and a home security system
Are Flyby Anomalies an ASTG Phenomenon? (ASTGII)
No full textThis reading expounds with expediency on the recently proposed Azimuthally Symmetric Theory of Gravitation(ASTG) set-up earlier. At its inspection,it was demonstrated that the ASTG is capable (among others solar anomalies) of explaining the precession of the perihelion of solar planets. In the present, we show that the ASTG is capable of explaining the puzzling observation
of ?yby anomalies, i.e. the anomalous asymptotic speed increases of the osculating
hyperbolic speed excess. It is shown that these ?yby anomalies occur naturally in the ASTG. We derive the empirical formula proposed by Andersonet al. in 2008,which up to now has no physical or foundational basis except that experience suggest it. If the ASTG model is correct,then for the ?rst time the Andersonet al.formula is given a physical meaning
Modelling within host parasite dynamics of schistosomiasis
No full textThis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. It is also available at: http://www.hindawi.com/journals/cmmm/2010/124376/abs/Schistosomiasis infection is characterized by the presence of adult worms in the portal
and mesenteric veins of humans as part of a complex migratory cycle initiated by
cutaneous penetration of the cercariae shed by infected freshwater snails. The drug
praziquantel is not always effective in the treatment against schistosomiasis at larvae
stage. However, our simulations show that it is effective against mature worms and
eggs. As a result, the study and understanding of immunological responses is key in
understanding parasite dynamics. We therefore introduce quantitative interpretations
of human immunological responses of the disease to formulate mathematical models
for the within-host dynamics of schistosomiasis. We also use numerical simulations to
demonstrate that it is the level of T cells that differentiates between either an effective
immune response or some degree of infection. These cells are responsible for the
differentiation and recruitment of eosinophils that are instrumental in clearing the
parasite. From the model analysis, we conclude that control of infection is much
attributed to the value of a function f, a measure of the average number of larvae
penetrating a susceptible individual having hatched from an egg released by an infected
individual. This agrees with evidence that there is a close association between the
ecology, the distribution of infection and the disease.African Mathematics Millennium Science Initiative (AMMSI)
The longitudinally excited continuous wave CO2 laser
No full textThe design and development of a longitudinally excited continuous wave carbon dioxide laser is discussed. Theory related to laser design and development is presented in chapters 1 and 2. A brief overview of the literature behind the CO2 laser is also outlined. In chapter 3 the design and development of the laser are discussed in detail and illustrations to help explain the intricacies of the various processes have been included. In this booked series of experimental results obtained with the developed CW CO2 laser that focusses on the basic characterisation of the laser are discussed. Beam profile analysis forms part of the experimental results that are presenteded
Structure, Creep and Fatigue Relationships of Nylon6.6 Tyre Materials
No full textCreep and Fatigue experiments were carried out on nylon6.6 tyre materials in order to
examine the structure-creep-fatigue relationships of these materials. Creep experiments were conducted at different temperature levels using a specially designed apparatus. Flex fatigue
experiments were conducted at ambient temperature. Materials under different stress levels were flexed over a pin. The results showed structural change in the nylon polymer during both creep and fatigue. This was highly influenced by change in temperature and stress level. High temperatures and stress levels accelerated molecular movement causing quick failure