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Molecular Characterization of Paramphistomes fromCattle from Matebeleland Region (Zimbabwe) using RandomAmplified Polymorphic DNA (RAPDs) and Amplified Ribosomal DNA Restriction Analysis (ARDRA)
No full textMolecular Characterization of Paramphistomes fromCattle from Matebeleland Region (Zimbabwe) using RandomAmplified Polymorphic DNA (RAPDs) and Amplified Ribosomal DNA Restriction Analysis (ARDRA) is a published article of the Applied Biology and Biochemistry department.Paramphistome isolates collected from local abattoirs were genetically characterised using the Random Ampl41i47fied
Polymorphic DNA (RAPD) technique and Amplified Ribosomal DNA Restriction Analysis (ARDRA). These isolates were
morphologically characterized using median sectioning and five putative species were identified. Of the 18 isolates that
were being investigated, 16 were positively identified: three belonged to Calicophoron calicophorum, two were
Calicophoron microbothrium, one was Gigantocotyle symmeri, 6 were identified as Calicophoron raja and the other 6
were identified as Calicophoron clavula. A restriction digest of the amplified ITS-2 region of all isolates was done using
two restriction enzymes Hae III and Sau 3A1 and the fragments obtained did not show any detectable polymorphisms on
all isolates. A total number of 110 bands were generated by RAPD-PCR and 91.82% of these were polymorphic with an
average genetic distance of 0.4810+/- 0.185 that showed substantial variability among the paramphistome isolates. The
RAPD-PCR technique however, gave banding patterns that on analysis were able to cluster (on the dendrogram) the
isolates into their respective species groups and even aid in identifying the two isolates that were not positively identified
morphologically as Calicophoron raja. A fragment of approximately 1300bp was generated from primer OPB 07 on
Calicophoron microbothrium isolates which can be used as a selectable marker for this species. The findings of the
present study therefore showed that the RAPD- PCR technique can be used for molecular identification of
paramphistomes
Are Photons Massless or Massive?
No full textThis is a journal articlePrevailing and conventional wisdom as drawn from both Professor Albert Einstein?s Special Theory of Relativity(STR) and our palatable experience, holds that photons are massless particles and that, every particle that travels at the speed of light must ? accordingly, be massless. Amongst other important but now resolved problems in physics, this assumption led to the Neutrino Mass Problem ? namely, ?Do neutrinos have mass?? Neutrinos appear very strongly to travel at the speed of light and according to the afore-stated, they must be massless. Massless neutrinos have a problem in that one is unable to explain the phenomenon of neutrino oscillations because this requires massive neutrinos. Experiments appear to strongly suggest that indeed, neutrinos most certainly are massive particles. While this solves the problem of neutrino
oscillation, it directly leads to another problem, namely that of ??How can a massive particle travel at the speed of light? Is not this speed a preserve and prerogative of only massless particles?? We argue herein that in principle, it is possible for massive particles to travel at the speed of light. In presenting the present letter, our hope is that this may aid or contribute significantly in solving the said problem of ?How can massive particles travel at the speed of light??Prof. Dr.P. Mundy, Dr. P. Makoni, Dr. D. J. Hlatywayo and Prof. Dr. Y.S. Nai
On the Secular Recession of Earth-Moon System as an Azimuthal Gravitational Phenomenon
No full textThis article is not published before being archived in our Institutional Repository.We here apply the ASTG-model to the observed anomalous secular trend in the mean Sun-(Earth-Moon) and Earth-Moon distances. For the recession of the Earth-Moon system, in agreement with observation, we obtain a recession of about 11.20 ? 0.20 cm/yr. The ASTG-model predicts orbital drift as being a result of the orbital inclination and the Solar mass loss rate. The Newtonian gravitational constant G is assumed to be absolute time constant. Standish (2005); Krasinsky and Brumberg (2004) reported for the Earth-Moon system, an orbital recession from the Sun of about (15.00?4.00) cm/yr; whileWilliams et al. (2004); Williams and Boggs (2009); Williams et al. (2014) report for the Moon, an orbital recession of about 38.00mm/yr from the Earth. The predictions of the ASTG-model for the Earth-Moon system agrees very well with those the findings of Standish (2005); Krasinsky and Brumberg (2004). The lost orbital angular momentum for the Earth-Moon system ? which we here hypothesize to be gained as spin by the two body Earth-Moon system; this lost angular momentum accounts very well for the observed lunar drift, therefore, one can safely safely say that the ASTG-model does to a reasonable degree of accuracy predict the observed lunar drift of about 38.00mm/yr from the Earth.National University of Science & Technology (NUST)?s Research & Innovation Department and Research Board: Prof.Dr. P. Mundy, Dr. P. Makoni, Dr. D. J. Hlatywayo and Prof. Dr. Y. S. Naik?
Magnetic susceptibility studies of the (Cr98.4Al1.6)100-x Mox alloy System
No full textProceedings of the South African Institute of Physics (SAIP), 2014. The 59th annual conference of the South African Institute of Physics.The magnetic susceptibility as a function of temperature, ??(??), on a spin-densitywave
antiferromagnetic (Cr98.4Al1.6)100-xMox alloy system in the concentration range 0 ? x ? 8.8
is reported in order to investigate the possibility of quantum critical behaviour in this alloy
system. N?el temperatures, TN, obtained from ??(??) measurements decrease with Mo
concentration and sharply tend towards 0 K at a critical concentration xc ? 4.5.
Antiferromagnetism is suppressed to below 4 K in alloys with x ? 4.5. Alloys in the
concentration range 0 ? x ? 3.0 depict an upturn in the ??(??) curves just above the N?el
temperature. The upturn is attributed to local magnetic moments formed around the impurity
atoms. The magnetic phase diagram of the alloy system points towards the existence of a
quantum critical point at the critical concentration x = xc. The suggestion of quantum critical
behaviour in this alloy system from previous electrical resistivity(??), Seebeck coefficient (??)
and specific heat (??p) measurements is corroborated in this study.South African National Research Foundatio
Are Photons Massless or Massive?
No full textAre Photons Massless or Massive? is a published article of the Applied physics department.Prevailing and conventional wisdom as drawn from both Professor Albert Einstein?s Special Theory of Relativity
(STR) and our palatable experience, holds that photons are massless particles and that, every particle
that travels at the speed of light must ? accordingly, be massless. Amongst other important but now resolved
problems in physics, this assumption led to the Neutrino Mass Problem ? namely, ?Do neutrinos have mass??
Neutrinos appear very strongly to travel at the speed of light and according to the afore-stated, they must be
massless. Massless neutrinos have a problem in that one is unable to explain the phenomenon of neutrino oscillations
because this requires massive neutrinos. Experiments appear to strongly suggest that indeed, neutrinos
most certainly are massive particles. While this solves the problem of neutrino oscillation, it directly leads to
another problem, namely that of ??How can a massive particle travel at the speed of light? Is not this speed a
preserve and prerogative of only massless particles?? We argue herein that in principle, it is possible for massive
particles to travel at the speed of light. In presenting the present letter, our hope is that this may aid or
contribute significantly in solving the said problem of ?How can massive particles travel at the speed of light?
Removal of Cr(VI) from Aqueous Solutions Using Powder of Potato Peelings as a Low Cost Sorbent
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 citedPotato peels which are a low cost, renewable agroindustry by-product were used for the removal of hexavalent chromium from
aqueous effluents. Batch experiments were carried out with an artificial effluent comprising of potassium dichromate in deionised
water. The effects of the initial hexavalent chromium concentration, dose of biosorbent, and removal kinetics were explored. An
adsorbent dosage of 4 g/L was effective in complete removal of the metal ion, at pH 2.5, in 48 minutes. The kinetic process of
Cr(VI) adsorption onto potato peel powder was tested by applying pseudo-first-order and pseudo-second-order models as well as
the Elovich kinetic equation to correlate the experimental data and to determine the kinetic parameters. The adsorption data were
correlated by the Langmuir and Freundlich isotherms. A maximum monolayer adsorption capacity of 3.28 mg/g was calculated
using the Langmuir adsorption isotherm, suggesting a functional group limited adsorption process. The results confirmed that
potato peels are an effective biosorbent for the removal of hexavalent chromium from effluent
Virulence factors and antibiotic resistance patterns of uropathogenic Escherichia coli
No full textThis is an article cover page
A study on Terry woven Fabrics? Dimensional stability and Areal Density during Wet processing
No full textA study on Terry woven Fabrics?
Dimensional stability and Areal Density during Wet processing,is a published article of the textile technology department.Experimental work on three fabrics, made from 100% cotton, with different pile ratios and yarn densities was conducted during wet processing. Areal density, dimensional stability, yarn crimp and yarn densities were investigated at three different stages of wet processing namely greige state,
bleached state and dyed state. Results showed an increase in dimensional contractions as pile ratio was
increased. Fabric dimensions were measured after each processing stage, and the widthwise contractions
were between 2.4% and 7.9% for all the fabrics whereas the lengthwise contractions were between 9.7%
and 14.6%. Areal density was determined using two methods thus by manual measurement and also by
calculation. The measure and calculated result both showed that the areal density for each fabrics
increased during all stages of wet processing. Generally warp crimp was higher than weft crimp for all
the three fabrics, at all three stages of fabric ion. Weft crimp was between 2% and 7% whereas warp
crimp was between 6% and 14%. The measured and calculated results were compared and analyzed using
regression analysis methods, and it was found that there was a correlation between the measured and
the calculated results. It was concluded that wet processes have a significant effect on dimensional
stability and areal density. Also it was concluded that the effect of wet processing is dependent on the
fabric construction parameters which include the pile ratio and yarn density
Implications For Post-dollarisation Market Efficiency
No full textAn Event Study Of The Zimbabwe Stock Exchange (ZSE):Implications For Post-dollarisation Market Efficiency is a published article of the marketing department.This paper investigates the impact of earnings (full-year, half-year and dividend) announcements
and cautionary statements on returns of ZSE listed companies post-dollarisation of the economy in 2009. A
standard CMRM based event study methodology (EVM) is applied to weekly returns from January 2010 to
December 2012. Findings suggest that earnings announcements and cautionary statements have no impact on
returns of companies traded on the ZSE characterised by a very weak correlation between ?good/bad news? and
the direction of significant CARs. We conclude that alleged insider trading, high costs of trading and market
undervaluation make it difficult for EVM to detect abnormal returns, thereby painting a picture of compliance
with the weak to semi-strong forms of the Efficient Market Hypothesis (EMH)