383 research outputs found
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Antioxidant enzyme profiles in a species of ornamental fish (koi)
No full textPresented at the Research Day 1999.The aim of this work was to determine whether, and at what levels, antioxidant enzymes are expressed in the various organs of the koi. The activity of the antioxidant enzymes catalase (CAT), glutathione peroxidase (GPX), NAD(P)H: :' quinone oxidoreductase (NQOR) and malondialdehyde (MDA) content were determined in tissue homogenates of liver, kidney, pectoral muscle, gills, eggs, blood, heart and intestine. There was a marked variability (up to tenfold difference) in enzyme activity in the various organs, but much less individual variability ( - three fold difference). NQOR activity was highest in eggs (- 5.56(A/min/mg). Catalase activity also found heterogeneously in all organs had its highest activity in the liver ( - 5.02(A/min/mg). GPX (selenium dependent) activity was highest in the liver (5.14(A/min/mg). Thiobarbituric acid reactive substances (MDA) content, a measure of lipid peroxidation was, significantly low in all organs and tissues with an A535/mg of 0.00145(0.0027. The results suggest that antioxidant enzymes are expressed in most organs of the koi and that this species of fish is likely to be protected when exposed to compounds that either undergo redox cycling or that exerl a direct oxidative stress.Biochemical and Molecular Biology Society of Zimbabw
Differential Effects Of Some Quinoline Antimalarial Drugs On Rat Antioxidant Enzyme Activities
No full textPresented at the Bio-Y2K meeting hosted by Rhodes University in the year 2000.Quinoline-based antimalarial drugs have played a crucial role in the fight against malaria for decades. However, with the resurgence in drug tolerance among malaria parasites worldwide. The onus is on drug designers to synthesize more effective and less toxic drugs. In this study we sought to determine the effects of quinine, and the synthetic quinolines primaquine and chloroquine, on antioxidant enzymes so as to gain a better understanding of their effects on various enzyme systems which might be of value in the development of new, safe and more effective drugs. We used the Sprague-Dawley rat as a model to study the effects of these drugs on various hepatic and renal antioxidant enzymes. Our results show that primaquine administration increased the activities of some antioxidant enzymes (superoxide dismutase, glutathione peroxidase, and catalase), whereas chloroquine increased the activity of only superoxide dismutase while decreasing that of glutathione peroxidase and catalase. These results indicate a predisposition of the organs towards oxidative damage as evidenced by increases in parameters of lipid peroxidation in the same organs. Unlike the two synthetic drugs, however, quinine did not appear to cause any significant alterations in the activities of the antioxidant enzymes and neither did it cause any oxidative damage in rat organs. From these results, we conclude that since quinoline is still an effective drug against some chloroquine-resistant strains of malaria,the renewed interest in quinoline drugs should aim to design and synthesize quinine analogues which are less toxic and have enhanced antimalarial activity
Privacy and public access: using Internet caf?s in Zimbabwe
No full textPaper presented at the 14th Information Studies (IS) Annual Conference, University of Zululand, South Africa, 4-6th September 2013People who use Internet caf?s, like any other Internet users, risk the invasion of their personal
privacy. This is because the Internet has become a ?field? for data mining. Evidence from
empirical research on the nature of the threat to personal privacy faced by Internet caf? users
when using the Internet in a developing country was not readily available; hence this study
which sought to contribute in closing this gap. The study consisted of two sections. The first
section, which was guided by an individualistic definition of privacy, involved a study of
Internet caf? operators in the City of Bulawayo, where data was collected through interviews,
and an analysis of websites of some of the institutional entities in Zimbabwe. Judgemental
sampling was used in both instances. Qualitative data was collected and analysed on the basis
of themes that emerged from the literature. The second section was a normative assessment
for postulating the way forward for Internet-based services in Zimbabwe
The findings showed that, overall, the country was in transition, especially as evidenced by
the state of the legislative regime. A data protection bill was at draft stage, and the Internet
Service Providers (ISPs) did not seem to be adhering to the current legislation that required
them to monitor transactions of Internet caf?s; and at the same time, the Internet caf?
operators reported that they were ignorant of the legislation that required them to observe the
personal privacy of their patrons. Some of the Internet caf?s had instituted measures to
protect their computers and patrons while others had not bothered. The normative assessment
concluded by recommending use of the communitarian position, utilitarian view and social
contract theory in developing a society that respects the personal privacy of its citizens in a
digital age.National University of Science and Technology Research Boar
The Engineering Council of Zimbabwe (ECZ) regulating the operations of Engineers and Engineering Technicians.
No full textPublished in The Chronicle of August 2013 on the productivity column.An Engineer is a professional mandated with using science to design and develop equipment, processes
and systems that make life desirable and easy to live. An engineer has been defined as, ?a professional
practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to
develop solutions for technical problems?. Engineers design materials, structures, and systems while
considering the limitations imposed by practicality, regulation, safety, and cost. Check around you and
admire the fruits of the engineer. You can hardly conduct your business without realizing or utilization
what has been developed by an engineer. This is not at the expense of other professions but just to
state the significance of the engineering profession in our lives. It complements and supplements many
other disciplines and professions and it is thus equally critical
Capitalising on advanced manufacturing technologies for global Competitiveness.
No full textPublished in The Chronicle Newspaper of 15 August 2013 on the productivity columnAdvanced Manufacturing Technologies involves the use of technology to improve products
and/or processes. The world keeps moving in many aspects and all nations have to catch up with
the swiftness with which any such movement is happening. One aspect of mention is the
advances that are happening in manufacturing technologies. These advances are exacerbated by
further and swift advances in information and communication technologies. All organisations
need to know and realise the technologies that are available in their areas of specialisation. This
should be done by some form of benchmarking. That way, there will be reason to map the way
forward
Geospatial Analysis of the Aquiferous Potential Zones in the Crystalline Basement of Bulawayo Metropolitan Area, Zimbabwe
No full text64th International Astronautical Congress, Beijing, China.Efforts have been made to review the literatures on groundwater exploitation and the constraints to effective and sustainable management of groundwater in Bulawayo Metropolitan, Zimbabwe. However, the attempts are hindered by the underlain crystalline basement aquifers which are complex in nature and highly heterogeneous in yield. Therefore this study seeks to demarcate the potential aquiferous zones in Bulawayo Metropolitan for groundwater development using satellite data and geological inference. Remote Sensing and Geographical Information Systems (GIS) are useful in the recognition and delineation of aquiferous zones for potential groundwater in crystalline basement aquifers. LANDSAT ETM+ image, SRTM data, aeromagnetic data and other ancillary data sets were utilized to extract information on the groundwater storing controlling features of this study area. GIS modeling using the index overlay method was used to produce the groundwater potential map. The study revealed that the regional lineaments correlate with faults, fracture zones, and lithological contrasts along fold belts in the crystalline basement rocks, while the main direction of faulting and jointing is north-north-west to north, with several faults oriented to the north-north-east parallel to the Zimbabwe Great Dyke. The areas close to lineaments are the highest zone of increased porosity and permeability, which in turn have a greater chance of accumulating groundwater. The results have shown massive spatial variability of ground water potential ranging from very good to poor. The variability closely followed variations in the structures, geology, topography/slope, drainage density and land use/land cover in the project area. This exploratory work needs to be validated by the use of high-resolution terrain data and satellite imagery, along with quantitative analysis, which should be done using geophysical and hydrogeological surveys
The Antimicrobial Efficacy Study of Pretreated Antimicrobial Silk Suture
No full textThe Antimicrobial Efficacy Study of Pretreated Antimicrobial Silk Suture is a published article of the Textile Technology department.In recent years many antimicrobial sutures have been developed in a quest to
deal with the problem of surgical site infections in the medical world. This study was
done to find out the effects of pre-treating the braided suture materials before applying
the antibacterial coating agent. 0.1N sodium hydroxide (NaOH) solution was used to pre
treat / pre scour the sutures to remove impurities and also to open the structure of the silk
sutures so as to allow the coating agent to penetrate into the suture structure. A
biodegradable polymer and an antibacterial drug, that is, polycaprolactone (PCL) and
Sulphamethoxazole trimethropm (SMZ) were used as the coating agent. The polymer
PCL was made into a solution of 10% whilst the drug SMZ was made into a solution of
2500 ?g/ml. 5cm pieces of silk braided sutures were first cut aseptically and then washed
in 0.1N NaOH solution and dried. After this pretreatment, they were coated with the
antimicrobial coating agent and then dried. The pretreated sutures were then evaluated
and compared, with non treated sutures acting as the control. Antimicrobial tests were
then carried out to find out the effects of pre-treated and non pre-treated sutures on the
antimicrobial properties of the sutures. Through this study it was found that the pretreated
sutures exerted a better sustained efficacy assay compared to those that are not
pretreated, however mechanical properties were lowered but were still within the required
standards for antimicrobial sutures
Magnetic properties of the (Cr -xAlx) V alloy system
No full textProceedings of the South African Institute of Physics (SAIP), 2013. The 58th annual conference of the South African Institute of PhysicsElectrical resistivity (?), Seebeck coefficient (S) and magnetic susceptibility (?)
measurements as a function of temperature on the (Cr -xAlx) V alloy system, with 0 < x
are reported. N?el temperatures (TN) obtained from all these measurements decrease with Al
concentration, disappearing near x ? 1.5, again reappearing for x ? . ?(T) and S(T) for
samples with x ? 6.1 show weak anomalies making the determination of TN difficult. However,
these anomalies are sharply defined in ?(T), proving that it is an important tool in probing
antiferromagnetic in this system. The present results show that the addition of just 1 at.% V to
the Cr -xAlx alloy system suppresses antiferromagnetism in the concentration range
5 ? x ? . This behaviour is similar to that observed for the (Cr -xAlx) 5Mo5 alloy system
Needs Analysis for Language, Communication and Related Competencies at National University of Science and Technology.
No full textReport Compiled for: Language & Communication Centre Records, Deans, Chairs Of Departments and Other Interested Parties,9 July 201
Cost of Quality as a Driver for Continuous Improvement - Case Study ? Company X
No full textPresented as part of the International Journal of Innovative Technology and Exploring Engineering (IJITEE)2013In the manufacturing, metal casting industry is one of the oldest basic principal and most important industries. The casting process is hindered by the occurrence of various defects. High casting reject levels and customer returns have a considerable adverse effect on productivity, delivery performance, customer satisfaction and employee morale. In addition excessive rejection reduces yield, wastes valuable raw materials and involves management time in problem solving. All foundry processes generate a certain level of rejection that is closely related to the type of casting, the processes used and the equipment available. This paper seeks to establish the extent to which cost of quality can impact on continuous improvement of the products and the relationship with the customers of the organization. To determine the cost of quality (COQ) at casting company X, the researchers used existing company records, publications and historical evidence of the company. The researchers utilized techniques such as, bar charts and tables in presenting and interpreting data. The above techniques have the ability to provide methods for collecting, presenting, and analysis and meaningfully interpret data. The research findings estimated the COQ to be 6.6% of sales revenue.International Journal of Innovative Technology and Exploring Engineering (IJITEE