383 research outputs found
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High Frequency Mesh Network for Control and Sensor Arrays
No full textThis is a journal articleThis paper explores wireless mesh networking by establishing short-range telemetry links in the Industrial Scientific and Medical (ISM) frequency band of 13.56MHz and demonstrating the forwarding capabilities of a mesh network. For this purpose three transceivers are designed and built which act as nodes on the network, two of which are embedded nodes.The transceivers are designed using Phase Locked Loops (PLLs)both as a signal source and a direct Frequency
Modulation (FM) demodulator
Lunar Drift Explains Lunar Eccentricity Rate
No full textLunar Drift Explains Lunar Eccentricity Rate is an articleIn this short letter, we argue that the observed +38mm/yr secular Lunar drift from
the Earth does ? to an admirable degree of agreement between theory and observa-
tions; explain the observed secular increase in the Lunar eccentricity. At present, the
recession of the Moon from the Earth is not any more considered as an anomaly as this
is believed to be well explained by conventional physics of Lunar-Earth tides. However,
the same is not true when it come to the observed increase in the Lunar eccentricity
which is considered to be an anomaly requiring an explanation as to what is the cause
behind this phenomenon. We not only demonstrate an intimate connection between
these two seemingly unrelated phenomenon, but show that the intimate relationship
that we deduce fits so well with observations to a point that ? logic dictates that, the
Lunar drift must surely be the cause of the secular increase in the Lunar eccentricity
Hepatic Cytosolic Glutathione S- Transferases of ostrich (struthio camelus): partial characterisation and interaction with xenobiotics.
No full textAn article with pictures.The glutathione S-transferases (GSTs) in affinity purified pools of male and
female ostrich liver were studied. The GSTs were purified from crude liver cytosols
by S-hexylglutathione sepharose affinity chromatography with yields comparable
to those reported for GST from mammalian livers. The K, for both glutathione
(GSH) and 1-chloro-2,4-dinitroSenzenzene (CDNB) were determined and found to be
within the range of values known for mammalian and invertebrate species. 1-
chloro-2,4-dinitrobenzene proved to be the best of nine substrates tested to
measure activity. Activity was inhibited by bromosulphophthalein and cibacron
blue which are well known inhibitors of the mammalian enzyme. Our results
indicate that the ostrich liver enzymes behave similarly to the mammalian liver
enzyme in terms of substrate requirements and inhibition characteristics.Zimban
On the Cosmic Variation of the Fine Structure Constant. Was the Universe Created at an Instant?
No full textThis is an articleWithout veering off the shores of conventional physics and without making any exogenous addition on our part, but well within the mathematical and physical logic of the accepted domains and confines of classical Maxwellian electrodynamics - in a very simple way, we pristinely demonstrate
that the variation of Fine Structure Constant (FSC) can be explained as a purely classical phenomenon without the need to resorting to exotic ideas as is the case in present day approaches to this problem. The need, spirited thrust and effort currently under-way to explain the variation of the FSC has been necessitated and triggered by observations of Quasar absorption lines from various ions of iron and magnesium by Professor John Webb and his collaborators who have interpreted their measurements as strongly pointing to a possible time and spacial variation of the FSC. Our interpretation of the variation of the FSC ? if correct, then, we may need to rethink if not reconsider anew, our standard cosmological models, especially those cosmological models that are beholden to the now seemingly sacrosanct notion that all matter, energy and all of existence as we know it, was created at an instant. If the ideas propagated herein on the proposed mechanism behind the variation of the FSC, then, we argue that it should be possible to resolve the issue of the distances of Quasars i.e., whether or not Quasars are at their cosmological distances
Effect of Changing Coating Process Parameters in the Preparation of Antimicrobial-Coated Silk Sutures: An In Vitro Study
No full textEffect of Changing Coating Process
Parameters in the Preparation of Antimicrobial-Coated
Silk Sutures: An In Vitro Study,is a published article of the textile technology department.Braided silk sutures were coated using a combination of poly(?-caprolactone) (PCL) and sulfamethoxazole
trimethroprim (SMZ) to investigate their antimicrobial performance. SMZ (2500 ?g/ml) was combined with different PCL
concentrations, i.e., 2.5 %, 5 %, 7.5 %, and 10 % (w/v). Antimicrobial test results showed that SMZ and PCL-treated silk
sutures exhibited increasing antimicrobial efficacy against Gram-negative (Escherichia coli) and -positive bacteria
(Staphylococcus aureus) with increasing PCL concentrations. The tensile and knot strength of sutures coated with 10 % PCL
were significantly higher than those of sutures coated with 7.5 %, 5 %, and 2.5 % PCL. Treatment with PCL exhibited a
positive effect on drug release from the sutures. Significant traits of antibacterial activity were observed up to 4 days after
instalment of 10 % PCL-coated silk sutures. Under a scanning electron microscope, untreated silk sutures showed a surface
heavily coated with bacteria, whereas treated sutures showed a smooth surface without bacteria. The results of this study
indicate that SMZ combined with high concentrations of PCL may afford a suitable antibacterial coating agent for braided
silk sutures
Development of a Low Cost Re-usable Microfibre Sanitary Pad
No full textDevelopment of a Low Cost Re-usable Microfibre Sanitary Pad is a published article of the textile technology department.Menstrual hygiene management is a big problem for women
and girls in Zimbabwe as the sanitary pads are expensive.
An average pack of 8-10 at $US1.50 is significantly expensive
for females coming from low income families, which has
caused women and girls to resort to unhealthy ways such as
using grass and cow dung for managing their menstruation,
which exposes them to infections. The aim was to develop a
low-cost re-usable microfibre sanitary pad with good
performance properties and low cost maintenance,
affordable to poor women. The design was based on the
Johnson and Johnson re-usable (a rectangular shape) sanitary
pads. The new re-usable pad was developed from polyester
microfibre materials. It has a pocket for an insert of another
material that will enhance the collection of blood. The
developed pad was tested for wicking, leakage and strike
through properties. The newly developed pad exhibited
better properties and yet cheaper than the commercial
disposable pads
A dynamic programming operations management algorithim in a tile manufacturing industry: Case study of a tile company
No full textA Dynamic Programming Operations Management Algorithim in a Tile Manufacturing Industry: Case Study of a Tile Company is a published article of the Applied mathematics department.This research paper combined optimization algorithms, capacity planning, scheduling and
discrete event simulation in the tile manufacturing plant, by determining the tooling, personnel and
equipment resources that are required for optimal efficiency in the manufacturing process. A Dynamic
Programming knapsack algorithm is used to optimally select jobs (in a 12-stage manufacturing process)
such that they contribute to the production plan within a specified duration of time (28 days). This was done
in such a way that each stage contributed to an overall optimal production plan for the tile manufacturing
process with minimal costs. It is recommended that the designing of production processes should match
volume-variety requirements, process design positioning and the incorporation of appropriate process
technology. Furthermore job designs, recognising process variability, appropriately configuring process
tasks, capacity and adopting a minimal cost task-precedence are also recommended
Funding Civil Justice in the Age of Fiscal Austerity: The Case of Zimbabwe
No full textFunding Civil Justice in the Age of Fiscal Austerity: The Case of Zimbabwe is a published article by Davis Nyangare of the Finance department.This paper tackles the issue of civil court funding in Zimbabwe against a background
of fiscal austerity. Having gone through a decade of economic meltdown and
political transformation from 1999 to 2009, Zimbabwe has to fund a wide range of
public services from a paltry public budget of less than 5 billion United States dollars
each year. Fiscal constraints have meant that very few resources are available to
fund critical public services such as defense and justice among others. This paper
examines the pricing of civil court services in Zimbabwe with a view to determining
the scope for improved user funding of the courts. Based on a survey of court
accountants and magistrates, the study reveals that key court employees in
Zimbabwe acknowledge, in principle, the need for enhanced measures to improve
user funding of civil justice in Zimbabwe. It emerges that cost recovery rates of
between 55% and 60% are attainable for Zimbabwe?s civil courts, without
significantly compromising access to justice. The inclusion of key court employees in
the survey is a significant departure from previous studies, which have focused
unduly on the views of court users. The study recommends realignment of
incentives within the civil justice system in order to improve the sharing of litigation
risk between lawyers and consumers of civil justice services, and open more space
for user funding of courts
Evolution of antimicrobial resistance of Salmonella enteritidis (1972?2005)
No full textThis is a journal article.With the extensive use of antibiotics in livestock production, surveillance revealed an increase in salmonella resistance to the commonly used antimicrobials in veterinary and public
health. This serious threat to health care is further exacerbated by the limited epidemiological information about the common zoonotic agent, Salmonella enteritidis, required to determine
antibiotic therapy. The aim was to characterise the antimicrobial resistance patterns of S. enteritidis isolates across different timelines (1972?2005) with accompanying genetic changes being investigated. Thirty-seven stored S. enteritidis isolates were collected from
the Central Veterinary Laboratory, Harare, with antimicrobial susceptibility determined against eight antibiotics. Plasmids were isolated to analyse any genetic variation. An overall significant increase in resistance (p < 0.05) to nalidixic acid (0% ? 10%), ampicillin (14.3% ?50%), tetracycline (14.3% ? 30%) and erythromycin (71.4% ? 100%) was observed across the timeline. However, the highest rates of susceptibility were maintained for gentamicin, sulphamethoxazole-trimethoprim, kanamycin and chloramphenicol. We report an increase
in multidrug resistance (MDR) of 14.2% ? 50% with an increase in resistotypes and plasmid profiles across the timeline. Eleven plasmid profiles were obtained in the 37 isolates studied with a minority of isolates (21.6%, 8/37) harbouring a 54 kb plasmid, commonly serovarspecific. A concerning increase in antimicrobial resistance to commonly administered drugs
was observed across the timeline. The surge in MDR is of great concern and implies the need for consistent antimicrobial stewardship. No correlation was observed between the plasmid and antibiotic profiles
Attitudes of Technical Teacher Education Student Teachers at University on the Use of Information Communication Technology for Learning and Teaching
No full textAttitudes of Technical Teacher Education Student Teachers at University
on the Use of Information Communication Technology for Learning and
Teaching is a journal article.The study provides an indication about the attitudes of female and male student-teachers on the use information
communication technologies in learning and teaching. Female learners? lack of interest against the high interest shown by
their male counterparts in learning and teaching has implications on their performance. The introduction of ICT in learning
and teaching requires student-teachers as classroom instructors to be competent in using ICTs for a variety of activities in
order to impart those skills to younger learners. The study sought to find differences between female and male students in the
use of ICT and investigated students? attitudes to assess whether access to computers, background, stereotype and
experiences influenced female and male participants in using ICT in teaching and learning. The objective of the study was to
discover attitudes of female and male students towards ICT. The study was also to discover differences in attitudes towards
ICT between female and male student teachers and to what extent these differences could be explained by students, lecturers
and student-teachers? experience factors. Female and male students were exposed to the use of computers at university in
different education programs that included student teachers from art and design, clothing, textiles and fashion design and
computer study areas among others. The study did not reveal wide gender differences in computer attitudes between female
and male student teachers as it showed that both female and male students developed computer knowledge and confidence in
working with ICT although male students used ICT for experimentation while female students used them more for set
assignments. From the results it is recommended that female student teachers use computers more freely in their student
activities for the purpose of acquiring a variety of computer skills and for the male student teachers to focus on specific tasks
of learning and teaching when using computers