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An evaluation of the antimicrobial activities of aloe barbadensis:A. chabaudii and A. arborescens leaf extracts used in folklore veterinary medicine in Zimbabwe
No full textAppears in the Journal of Animal and Veterinary Advances 9 (23): 2918-2923, Medwell Journals, 2010The antimicrobial activities of Aloe barbadensis Miller(Aloe vera), A. chabaudii and A. Arborescens sap extracts on selected microorganisms were determined. Methanol as well as aqueous extracts of these plants were obtained and then tested for their antimicrobial activities using the disc diffusion assay. The extracts were assayed againstgram positive bacteria (Staphylococcus aureus, Bacillus substilis), gram negative bacteria (Escherichia coli, Salmonella typhimurium, S. gallinarum, Klebsiellasp., Proteussp.) and Candida albicans. The study showed that the sap extracts of the three Aloes had antimicrobial activity against all the tested microorganisms. The antimicrobial activity of the methanol extracts were significantly higher than those of the aqueous (warm and cold) extracts (one tailed t-test, p<0.05). There was no significant difference in the antimicrobial activities of the aqueous extracts (one tailed t-test, p<0.05). S. typhimurium and S. gallinarum were the least susceptible to the extracts tested E. coli, Proteussp., Klebsiellasp. and C. albicans were the most sensitive.National University of Science and Technology
(NUST) Research Board
Lepton Generation Problem Some Properties and Implications of the Curved Space Time Dirac Equation ( Curved Spacetime Dirac Equation II).
No full textThis reading is a continuation of the earlier reading of Nyambuya (2008)Where three new Curved Spacetime Dirac Equations have been derived mainly to try and account in a natural way for the observed
anomalous gyromagnetic ratio of fermions and the suggestions is that particles including the Electron, which is thought to be a point particle, do have a finite spatial size and this is one of the reasons for the observed
anomalous gyromagnetic ratio. Combining the idea in Nyambuya (2008) which lead to the derivation of the three new Curved Spacetime Dirac Equations, and the proposed Unified Field Theory (Nyambuya 2007), a
total of 12 equations each with 16 sub-components are generated thus leading to a total of 192 equations for
the Curved Spacetime Dirac Equation. Some symmetries of these equations are investigated, i.e., the Lorentz
symmetry, charge conjugation symmetry (C), time reversal symmetry (T), Space reversal (P) and a combination
of the C, P&T-symmetries. It is shown that these equations are Lorentz invariant, obey C-symmetry and that
some violate T and P-symmetry while others do not and that they all obey PT-symmetry. These symmetries
show (or modestly said ? seem to suggest) that anti-particles have positive mass and energy but a negative
rest-mass and the opposite sign in electronic charge. Through the inspection of these symmetries, a suggestion
is (here) made to the effect that the rest-mass of a particle must be related to the electronic charge of that
particle thus leading us to a possible resolution of whether or not Neutrinos do have a none-zero rest-mass.
Additionally, we demonstrate that these equations have the potency to explain naturally the observed lepton
generation phenomena
A comparison of metal levels and antioxidant enzymes in freshwater snails,Lymnaea natalensis, exposed to sediment and water collected from Wright Dam and Lower Mguza Dam, Bulawayo, Zimbabwe.
No full textThe journal article is available online at ScienceDirectWe compared the bioaccuniulation of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), nickel (Ni) and
iron (Fe) with antioxidant enzyme activity in tissues of the snails, Lymnaea natalensis, exposed to
elements of two differently polluted dams. 45 snails were exposed to sediment and water collected
from Wight Dam (reference) whilst another 45 snails were also exposed to sediment and water
collected from Lower Mguza Dam (polluted dam). Except for Fe in sediment and Pb in water, metal
concentrations were statistically higher in sediment and water collected from Lower Mguza Dam. Lead.
Cd and Zn were two times higher in tissues of snails exposed to Lower Mguza Dam elements. On one
hand, superoxide dismutase (SOD), diphosphotriphosphodiaphorase (DTD) and catalase (CAT) activities
were significantly lower whilst malondialdehyde (MDA) levels were significantly higher in tissues of
snails exposed to Lower Mguza Dam sediment and water. On the other hand, selenium-dependent
glutathione peroxidase (Se-GPX) activity was significantly elevated in tissues of snails exposed to Lower
Mguza Dam sediment and water. Snails exposed to Lower Mguza Dam elements seem to have
responded to pollution by increasing CAT and Se-GPX specific activity in an effort to detoxify peroxides
produced as a result of metal induced oxidative stress.International
Program for Chemical Sciences, Sweden and Research Board,
National University of Science and Technology, Zimbabwe
A Quasi-Linear Model Of Design Cognition
No full textAvailable online at http://journals.cluteonline.com/index.php/TLC/article/view/246/236The continuum of human learning has been the subject of research by behaviourists, cognitivists,
constructivists and lately by neural scientists among others. The style and order of learning have
also been identified, notably by Benjamin Bloom et al (1956) and Gagne and Briggs (1992).
Skills-learning has been the subject of attention in competency-based learning strategies. Yet
another milestone in the continuum of learning is to be innovative and creative, which enables a
learner to conceive and design new objects and concepts. Design cognition is an under-explored
faculty of humankind. Human capability to design appears to be a complex phenomenon
influenced by several factors, implicitly or explicitly, such as socio-educational background,
learning to think innovatively, interaction with innovators and creators, exercising initiative,
experimenting with new ideas, creating designs with confidence and finally moving into seeking
design patents and making commercial use of design. In this paper the authors develop first a
linear model of acquiring design capability and then modify it to a quasi linear model after
validation by interaction with a sample of design students and design professionals through
analysis and reflection on questionnaire responses with both qualitative and quantitative data.
The proposed model promises to be a useful tool for design educators in several overlapping
areas of design
Effect of leaf size, thorn density and leaf accessibility on instantaneous intake rates of five woody species browsed by Matebele goats (Capra hircus L) in a semi-arid savanna, Zimbabwe
No full textBrowse instantaneous intake rate (IIR) is a product of bite size and bite rate which are constrained by plant morphology. We studied the effects of leaf size, thorn density and leaf accessibility on the IIRs of five browse species in semi-arid savanna over three leaf phenophases using cafeteria-style trials. Bite size was influenced by leaf size and bite rate by leaf accessibility, while thorn density had an impact on both bite size and bite rate. The lowest IIRs were recorded on the small leafed Acacia tortilis which also had the highest thorn density. Dichrostachys cinerea had the highest IIRs due to the large bite sizes. Although Terminalia prunioides and Commiphora pyracanthoides had small leaves, their arrangements in clusters allowed for higher IIRs, which were comparable to those of the large leafed D. cinerea. Instantaneous intake rate showed no clear trend in relation to leaf phenophase, although at early leaf the goats cropped smaller bites because of the small size of the newly sprouting leaves. We conclude that leaf size influenced IIRs through bite size, leaf accessibility through bite rate and thorn density through both bite size and bite rate
Engineering Research On Wind Energy And Its Impact On Provision Of Safe Drinking Water To Improve The Livelihoods Of Rural Communities In Zimbabwe.
No full textDescriptive studies on Paramphistomes of small domestic ruminants in Southern Nigeria
No full textGoats and sheep slaughtered in Southern Nigeria had their rumens and reticulums examined for the frequency and intensity of infections with paramphistomes. The overall frequency of infected goats and sheep was 30% and 80% respectively. The range of intensity of parasite in goats and sheep was, 2 to 500 and 2 to 700 respectively. From the morphological and histological studies of diagnostic features, which included the acetabulum, genetilium and
pharynx, carried out on flattened whole mounts and median sagittal sections the following parasites were identified, Cotylophoron cotylophorum infecting 8% of the goats,Cotylophoron fuelleborni infecting 20% of the goats, Carmyerius synethes infecting 4% of the goats and 70% sheep, and Calicophoron microbothrium infecting 20% of the goats and 33%,sheep. Goats were infected with all the four species while sheep infected with only the last two species. The degree of tissue damage on both hosts was mild
A comparison of metal levels and antioxidant enzymes in freshwater snails, Lymnaea natalensis, exposed to sediment and water collected from Wright Dam and Lower Mguza Dam, Bulawayo, Zimbabwe
No full textEcotoxicology and Environmental SafetyWe compared the bioaccumulation of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), nickel (Ni) and
iron (Fe) with antioxidant enzyme activity in tissues of the snails, Lymnaea natalensis, exposed to
elements of two differently polluted dams. 45 snails were exposed to sediment and water collected
from Wight Dam (reference) whilst another 45 snails were also exposed to sediment and water
collected from Lower Mguza Dam (polluted dam). Except for Fe in sediment and Pb in water, metal
concentrations were statistically higher in sediment and water collected from Lower Mguza Dam. Lead,
Cd and Zn were two times higher in tissues of snails exposed to Lower Mguza Dam elements. On one
hand, superoxide dismutase (SOD), diphosphotriphosphodiaphorase (DTD) and catalase (CAT) activities
were significantly lower whilst malondialdehyde (MDA) levels were significantly higher in tissues of
snails exposed to Lower Mguza Dam sediment and water. On the other hand, selenium-dependent
glutathione peroxidase (Se-GPX) activity was significantly elevated in tissues of snails exposed to Lower
Mguza Dam sediment and water. Snails exposed to Lower Mguza Dam elements seem to have
responded to pollution by increasing CAT and Se-GPX specific activity in an effort to detoxify peroxides
produced as a result of metal induced oxidative stress.supported by Grants from International
Program for Chemical Science
Studies on the Effects of Reducing the Period of Using Starter Mesh and Application of Probiotics to Broiler Chickens.
No full textInternational Journal of Poultry Science 8 (12): 1128-1131, 2009Two sets of 150 day old broiler chickens were fed with starter mesh for 14 and 21 days respectively and there after given grower mesh until day 35 after which both were fed on finisher until day 42. There was
no significant difference in the final carcass mass of both (p>0.05). Another trial was set up to investigate the effect of application of probiotics as liquid and as powder on 2500 birds per treatment and a control with no probiotics was also set up. The results showed that probiotics applied as liquid had the best effect on PEF
and FCR. The experiment to determine the best time to apply probiotics was conducted on 2000 birds per treatment. The results showed that the best performance was obtained when application of probiotics was
started at 14 days The PEF was also highest on birds which started probiotics on day 14
Improving Lives Stock Development in ACP Countries: The role of Science, Technology and Innovation in addressing the challenges to food security and economic empowerment
No full textThis policy brief outlines the major constraints to livestock development in ACP countries. It
places emphasis on the need for building science and technology capacity and applying advances
in science and technology to enhance innovation in livestock productivity, marketing and trade. It
also identifies the need for improving the ST&I policy framework for creating the enabling
environment to enhance the performance of the livestock sector and its contribution to food and
nutrition security, trade and economic growth and prosperity