Showing items 361 - 380 of 523

Your selections:

Effects of natural antioxidants and thermal treatment on quality of meat from Bonsmara and non-descripts cattle

  • Authors: Falowo, Andrew Bamidele
  • Date: 2015
  • Subjects: Meat -- Preservation Antioxidants Meat -- Microbiology
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10353/2589 , vital:27906
  • Description: The broad objective of this study was to determine the effects of natural antioxidants and thermal treatment on quality of meat from Bonsmara and non-descript cattle. A survey was conducted among 222 consumers in Alice (Fort Hare University community), Eastern Cape Province to determine the level of their awareness on application of antioxidants as preservatives in meat and meat products during storage. Representative samples of Muscularis longissimuss thoracis et lumborum and liver were collected from each carcass of Bonsmara (n=40) and non-descript (n=40) cattle reared on natural pasture to determine the effect of natural antioxidants and thermal treatment on their quality. The results from the survey revealed that 51.35 percent of the respondents had not heard about the use of antioxidant as preservatives in meat products. However, among the remaining respondents (48.65 percent) that were aware of antioxidant and its use as preservative, about 19 percent knew of natural antioxidants, 35 percent synthetic antioxidants while 46 percent had knowledge of both. The results further revealed that the majority of the respondents (82 percent) that had knowledge of natural antioxidants were concerned about the use of synthetic antioxidants in meat and meat products due to their health consequences. The in vitro antioxidant and antibacterial analyses of Bidens pilosa and Moringa oleifera leaf extracts revealed that they contain rich bioactive compounds. Furthermore, the addition of leaf extracts from Moringa oleifera (ML, 0.05 and 0.1 percent w/w) and Biden pilosa (BP, 0.05 and 0.1 percent w/w) to ground raw beef as a natural antioxidant were found to improve the physicochemical, oxidative stability and microbiological qualities of meat compared to the control (meat without extract) and BHT treatment (0.02 percent w/w) during 6 days storage at 40 C. Cattle breed did not have much effect on colour parameters. However, the overall pH of ground beef treated with extracts showed lower values than control and BHT treated beef. Also, ground beef samples containing extracts exhibited (P < 0.05) better colour stability, especially higher redness (a* values), than the control. The formation of TBARS in beef samples treated with extracts was significantly (P < 0.05) lower than the control and BHT treatment. The antibacterial assay of the extracts revealed an appreciable broad spectrum activity against the tested bacteria and microbial counts in ground beef samples compared to control and BHT group. Ground beef treated with plant extracts exhibited lower microbial and lactic acid bacterial counts (P < 0.05) at day 0 and 3 than control samples. Moreover, it was observed that application of sous vides thermal method did not significantly affect the fatty acids and mineral loss in beef and liver across the treatments. However, the total concentration of MUFA was lower in raw liver (20.11±2.38 - 21.08±1.23 percent) than in beef (40.22±1.90 - 42.53±1.29 percent), while total PUFA content were higher in liver (30.73±2.60 - 31.11±1.19 percent) than in beef samples (10.13±3.36 - 11.02±2.74 percent) (p < 0.05). The results also revealed that liver samples from Bonsmara and non-descript cattle had a higher percentage of intramuscular fat content of 4.67 ± 0.53 percent and 4.44 ± 0.53 percent respectively, and fat free dry matter of 27.51 ± 1.05 percent and 25.73 ± 1.05 percent, respectively, than the beef samples (p < 0.05). The concentrations of Mg (52.80±0.22 - 53.70±0.02mg/100g) and Zn (8.90±0.15 - 19.60±0.15mg/100g) were higher in beef than liver samples. The level of Ca (17.00±0.17 - 17.50 ± 0.17mg/100g) in liver was higher than that of beef samples. It was concluded that most consumers preferred the use of natural antioxidants in meat products than synthetic antioxidants due to their health risk. The effectiveness of M. oleifera and B. pilosa leaf extracts on meat quality also revealed that these plants are promising candidates as natural preservatives and their application should be considered in the meat industry. Lastly, findings from this study showed that application of the sous vide technique could protect meat products from nutritional loss during thermal treatment.
  • Full Text:

Enabling and constraining factors in Zimbabwe's 3-3-3 teacher education curriculum model : the case of a secondary teacher education college

  • Authors: Shava, Nosizo
  • Date: 2015
  • Subjects: Education -- Curricula -- Zimbabwe Teacher participation in curriculum planning -- Zimbabwe Teachers -- Training of -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/5686 , vital:29362
  • Description: This study offers an explanation of enabling and / or constraining factors in Zimbabwe‘s 3-3-3 secondary teacher education model for Post ‗O‘ Level Science. It is a theory driven study that derives its theoretical foundation from Roy Bhaskar‘s critical realism and Margaret Archer‘s morphogenetic approach to reality. The study therefore offers explanations about structural, cultural and agential influences that facilitate and / or hinder the 3-year program for Post ‗O‘ Level Science. This was a qualitative case study of one secondary teacher education college in Zimbabwe. Qualitative data were collected through interviews, focus group discussions and document analysis. One official from the Department of Teacher Education(DTE) at the University of Zimbabwe(UZ),the Principal, the Vice Principal and 10 lecturers from the studied college,3 Heads of Science department in secondary schools,3mentors and 5 groups of 10 and 11eleven student teachers participated in the study. The DTE Handbook (2012), vision and mission statements and core values of the Ministry of Higher and Tertiary Education Science and Technology Development (MHTESTD),DTE and the studied college, syllabuses, teaching practice reports, policy documents, external examining reports, College Academic Board (CAB) minutes, admission records, mark profiles and pass lists among other relevant documents complemented interview data. As a theory driven study, structural, cultural and agential influences were found to be enabling and / or constraining the model. The acute shortage of Science teachers in secondary schools and the few Post ‗A‘ Level Science graduates led to the re-introduction of the 3- year Post ‗O‘ Level Science program in secondary teacher education colleges. The bureaucratic structures in educational institutions, the In-Out-In structure, institutional structures such as the family, the University, the studied college, secondary schools, infrastructural facilities, material and financial resources, transport facilities and utilities such as water, electricity and the internet were established as some among other structural factors affecting the 3-3-3 model. Discourses held about the teaching profession, the vision, mission and core values of the MHTESTD,DTE and the studied college, beliefs about what Science teachers should learn, knowledge, skills, attitudes and values they should acquire and how they should be taught were established as cultural factors enabling and / or constraining the 3-3-3 model. Agential influences offering causal explanation for enablers and / or constrainers of the model were established as the decision by the Principal and the CAB to re-introduce the 3- year Post ‗O‘ Level Science program, the decision by the students to enroll for the program, the recruitment of under qualified students, the use of various teaching methods, conducting staff development and mentorship workshops and failure to increase staff establishment. The study has put forth recommendations for the improvement on constraining factors in pre-service teacher education programs. With the understanding that agency has power to reinforce or transform structures and cultures, it should not be seen to be reinforcing disadvantaged structural positions and cultures; instead, after having identified structural and cultural constrainers, it should engage in communicative and meta-reflexivity to come up with the best possible solutions to the hindrances. Courses of action should then be taken accordingly.
  • Full Text:

Evaluation of the quality indices of the final effluents of two wastewater treatment plants in buffalo City Metropolitan Municipality in the Eastern Cape Province

  • Authors: Osuolale, Olayinka O
  • Date: 2015
  • Language: English
  • Type: Thesis , Doctoral , PhD (Microbiology)
  • Identifier: vital:11292 , http://hdl.handle.net/10353/d1021079
  • Description: Waste waters can be sources of pollution to surface water and the environment with severe implications for public health. Most treatment plants in the Buffalo City Municipality in the Eastern Cape Province discharge their treated effluent into the surface waters which directly and indirectly impacts on the quality of surface waters in the region. The objective of this study was to determine the microbiological and physicochemical qualities of the final effluents of two wastewater treatment plants in the Buffalo City Municipality in the Eastern Cape Province of South Africa over a period of 12 months (September 2012 to August 2013). The qualities of the final effluents of WW-Ama Wastewater Treatment Plant with respect to phosphate (3.9 mg/l - 20.6 mg/l), free chlorine (0.05 mg/l - 0.71 mg/l), chemical oxygen demand (COD) (4.7 mg/l - 211 mg/l), and faecal coliform (0 - 2.92 × 104 CFU/100 ml) were not in compliance with the permissible limits set for effluent discharged to surface water by South Africa guidelines for effluent discharge. Other physicochemical parameters like biological oxygen demand (BOD) (2.2 mg/l - 9.0 mg/l), total dissolve solid (TDS) (253 mg/l - 336.3 mg/l) and turbidity (4.8 NTU - 43.20 NTU) with no SA regulatory set limits were compared to other regulatory standards and they do not comply with the limits. Also, at the second WWTP’s, the WW-Dim Treatment Plant effluent quality for free chlorine (0.06 mg/l - 7.2 mg/l), BOD (0.1 mg/l - 7.4 mg/l), and turbidity (4.02 NTU - 24.3 NTU) also did not comply. For microbiological qualities, counts of presumptive E. coli and Vibrio ranged between 0 - 2.92 × PROFESSOR ANTHONY I. OKOHAntibiogram of the bacterial isolates were determined using the disk diffusion method. A total of 107 confirmed E. coli and 100 confirmed Vibrio spp. were used for this assay. Results of antibiotic sensitivity test revealed that 63.6% of the E. coli isolates were resistance to ampicillin while 49.5% were resistant to tetracycline and cephalothin. The least resistances were observed against gentamicin (3.7%) and cefotaxime (1.9%). No resistance was observed against meropenem. For the Vibrio spp, resistance was most frequently observed against tetracycline (38%) ampicillin (26%), chloramphenicol (16%), cefotaxime (14%), trimethoprim-sulfamethoxazole (13%) and the least resistance observed was against ciprofloxacin (1%). This study demonstrates that poorly treated wastewater effluent can be a source of eutrophic water with high nutrient levels and pathogenic bacteria and enteric viruses as well as antibiotic resistance determinants that could impact negatively on human health. The finding of this study also suggests that WWTPs have to be properly monitored and controlled to ensure compliance to set guidelines. This could be attained through the application of appropriate treatment processes, which will help to minimize possible dangers to public environment health.
  • Full Text:

Graduateness and employability: a case of one polytechnic in Zimbabwe

  • Authors: Mutirwara, Miriam
  • Date: 2015
  • Subjects: Occupational training Employees -- Training -- Zimbabwe College graduates -- Employment -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD (Education)
  • Identifier: http://hdl.handle.net/10353/6125 , vital:29493
  • Description: The study explored the domains of graduateness and employability at one polytechnic in Zimbabwe. The focus was on how instructional delivery strategies and assessment tools could embed domains of graduateness and employer expectations. A phenomenological research approach was used in conducting the study. This qualitative research paradigm allowed the research to take place in a natural setting which enabled a holistic picture and use of an inductive mode of inquiry through the researcher’s immersion in the research setting. Human capital, teaching methods and flexible training models, among others, emerged as major strengths in training. However, these key strengths were marred by unprofessional practices and limited resources. In assessment, proficiency schedules, trade testing and use of external assessors emerged as key strengths. Pertaining to the curriculum, it emerged that on paper, curriculum specifications and design for implementation appeared relevant to the production of a graduate exhibiting attributes of graduateness. It however emerged that there was need to revisit the hidden curriculum, as training was dependent on the availability of resources. The study proposes a framework for promoting graduateness and enhancing employability through creation of mutual partnerships to collectively develop a curriculum that is acceptable to institutions and industry. Moreover, graduateness domains should be enshrined in the curriculum. A need for strategic selection of teaching and assessment methods which promote critical thinking, interaction, decision making and retention of information was identified. Major recommendations are that institutions should align themselves with market demands and technological changes to ensure employability. Institutions should also prepare graduates for transition to the world of work, by rendering adequate preparation through teaming up with industry and the use of appropriate teaching methodology.
  • Full Text:

Implication of tillage, texture and mineralogy on the sieving efficiency, physical-based soil organic matter and aggregate stability of some soils in the Eastern Cape

  • Authors: Peter, Prince Chinedu
  • Date: 2015
  • Subjects: Tillage Soil management -- South Africa -- Eastern Cape Soil physics -- South Africa -- Eastern Cape , Soil structure -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/2710 , vital:28058
  • Description: Soil structure and its associated physical properties are essential soil components. Soil texture and mineralogy are inherent soil properties that influence soil management. This study assessed the implication of tillage, texture and mineralogy on soil sieving, aggregate stability indices and physical fractions of organic matter in soils of Eastern Cape Province of South Africa. An Iris FTLVH – 0200 digital electromagnetic sieve shaker (Filtra Vibraciόn SL Spain), was used to determine settings for sieving efficiency. Mean weight diameter (MWD), water stable aggregate (WSA), state of aggregation (SA), dispersion ratio (DR), water dispersible clay (WDC), clay dispersion ratio (CDR), clay flocculation index (CFI), and potential structural deformation index (PSDI) were aggregate stability indices evaluated to check for sensitivity in evaluating aggregate stability of soils under two tillage systems and physical fractions of carbon and nitrogen in soils of Eastern Cape Province. The T4I3P2 and T4I4P3 settings were sensitive under tillage and T4I1P4, T3I4P3 and T4I4P3 were sensitive under mineralogical considerations for sieving efficiency. The total carbon in soils under conventional tillage (CT) was 17.7 g/kg and in soils under no tillage (NT) it was 15.8 g/kg. The total carbon content in the clay fraction of soils under CT was 24.1 percent higher than the total carbon content in the clay fraction of soils under NT. The total nitrogen content in the clay fraction of soils under CT was 5.4 percent higher than the total nitrogen content in the soils under NT. The total carbon in the sandy loam (SL) textured soils was 17.4 g/kg and in the sandy clay loam (SCL) textured soils it was 17.1 g/kg. The total nitrogen in SL soils was 3.7 g/kg and in SCL soils it was 3.7 g/kg. The clay fraction had higher total carbon than other fractions in Sl and SCL soils. The higher values of nitrogen were observed in the silt fraction for SL soils and clay fraction for SCL soils. The total carbon in the soils dominated with kaolinite was 17.3 g/kg and in quartz dominated soils the value was 16.9 g/kg. The total nitrogen in the soils dominated with kaolinite was 3.7 g/kg and in the soils dominated with quartz the value was 3.7 g/kg. For soils under NT the WDC was 135.8 g/kg and for soils under CT it was 139.7 g/kg. The ASC was 72.5 for soils under NT and 92.0for soils under CT. The DR was 0.9 for soils under NT and 0.8 for soils under CT. The CFI was 0.5 for soils under NT and 0.5 for soils under CT. The CDR was 0.5 for soils under NT and 0.5 for soils under CT. The MWDw was 1.6 mm for soils under NT and 1.4 mm for soils under CT. The MWDd was 4.0 mm for soils under NT and 4.0 for soils under CT. The percent WSA > 0.25 mm was 61.7 percent for soils under NT and 56.2 percent for soils under CT. The PSDI was 55.2 percent for soils under NT and 61.15 percent for soils under CT. The SA was 43.2 percent for soils under NT and 37.89 percent for soils under CT. The WDC was 125.7 g/kg for SCL soils and 151.4 g/kg for SL soils. The CDR was 0.5 for both SCL and SL soils. The DR was 0.9 for SCL soils and 0.8 for SL soils. The CFI was 0.5 for both SCL and SL soils. The ASC was 56.2 g/kg for SCL soils and 115 g/kg for SL soils. The MWDw was 1.5 mm for SCL soils and 1.4 mm for SL soils. The MWDd was 3.6 mm for SCL soils and 3.6 mm for SL soils. The percent WSA > 0.25 mm was 53.0 percent for SCL soils and 62.5 percent for SL soils. The PSDI was 59.2 percent for SCL soils and 59.7 percent for SL soils. The SA was 33.6 percent for SCL soils and 45.2 percent for SL soils. The WDC was 313.3 g/kg for kaolinitic soils and 120.7 g/kg for quartz dominated soils. The CDR was 0.5 for kaolinitic soils and 0.5 for quartz dominated soils. The DR was 0.9 for kaolinitic soils and 0.8 for quartz dominated soils. The CFI was 0.5 for kaolinitic soils and 0.5 for quartz dominated soils. The ASC was 110.0 g/kg for kaolinitic soils and 101.7 g/kg for quartz dominated soils. The WSA > 0.25 mm was 57.3 percent for quartz dominated soils and 68.4 percent for kaolinitic soils. The MWDw was 1.6 mm for quartz dominated soils and 0.8 mm for kaolinitic soils. The MWDd was 3.6 mm for quartz dominated soils and 3.4 mm for kaolinitic soils. The PSDI was 56.3 for quartz dominated soils and 76.0 for kaolinitic soils.
  • Full Text:

Intangible heritage: the production of post-apartheid memorial complexes

  • Authors: Dondolo,Luvuyo
  • Date: 2015
  • Subjects: Historic sites -- South Africa Cultural property -- South Africa Memorials -- South Africa Post-apartheid era -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , Degree
  • Identifier: http://hdl.handle.net/10353/3044 , vital:28242
  • Description: This study explores a number of issues relating to the nature and scope of intangible heritage and critically examines some of its salient components in South Africa. It affirms that intangible heritage is socially constructed. Aspects of intangible heritage that seem inherited in the present are social constructs and products of social progression. They present the historical development of the practicing communities. Furthermore, this study affirms that all heritage is intangible. This is expounded in the study by exploring the history of the concept of intangible heritage over the decades which provide its evolution both at international and national levels, and within heritage institutions. Heritage cannot be understood and defined in terms of traditions, indigenousness, pre-colonialism, North and South dichotomies or Western and non-Western dichotomies. This definition would racialise and regionalise heritage, and politics of indigeneity would surface. The separation of tangible, intangible and natural heritage is an artificial demarcation that is for heritage management discourse.
  • Full Text:

Isolation, characterisation of terpenoids and biosynthesis of silver nanoparticles of acacia mearnsii de wild and acacia Karroo Hayne and their Bioassays

  • Authors: Avoseh, Opeyemi Nudewhenu
  • Date: 2015
  • Language: English
  • Type: Thesis , Doctoral , PhD (Chemistry)
  • Identifier: vital:11355 , http://hdl.handle.net/10353/d1021292
  • Description: Great wealth of traditional knowledge about the use of plants had been transferred from generation to generations leading to the present day drug discovery and invention of new scientific methods of isolation, purification and identification. With the discovery of new diseases and drug-resistant organisms, there is no other source or deposit of lead compounds or drugs than the plant kingdom. As a result of this, about 25% of the current drug administered owe their origin to plant sources with the view to reduce the carcinogenic effect of synthetic drugs. Volatile terpenoids among other broad spectrum of natural product had been implicated to show high therapeutic properly. In the present study, selected locally-used medicinal plants were exploited for the presence of potent bioactive compounds and ability to form nanoparticles with distinctive property for use as chemoprotective agent against inflammation, tumors, cancer and other chronic diseases. Acacia mearnsii De Wild and Acacia karroo Hayne studied in this report are known to be invasive species with no proper regulation to conserve and preserve them. However, ethnopharmacology report of these plant species in the Southern Africa region reveals that they are good antiseptic, anti-diarrhea, anti-inflammation and a forage for livestock. These plants were subjected to volatile extraction protocol of some parts of the plants (stem and leaves) followed by examination of the anti-inflammation capacity of the extracts using an animal model. In addition, the bye-product (hydrosol) from the stem bark of each species possess a high reducing and stabilizing property leading to synthesis of silver nanoparticles, followed by investigation of the anti-inflammation potential of the synthesized silver nanoparticles using animal model. The volatile oils of the leaves and stem bark of Acacia mearnsii De Wild obtained by hydro-distillation were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Twenty, Thirty-Eight, Twenty-nine and Thirty-Eight components accounting for 93.8%, 92.1%, 78.5% and 90.9% of the total oils of the fresh, dry leaves and fresh, dry stem bark respectively. The major components of the oil were octadecyl alcohol (25.5%) and phytol (10.5%); cis-verbenol (29.5%); phytol (10.1%) and phytol (23.4%) for the fresh leaves, dried leaves, and fresh stem, dry stem bark respectively. Oral administration of essential oils at the dose of 2% showed significant (p<0.05) anti-inflammatory properties in the albumin induced test model in rats. Oils from the fresh leaves and dry stems inhibited inflammation beyond 4 h post treatment. Furthermore, the chemical composition of the essential oils obtained by hydro-distillation from the leaves and stem bark (dry and fresh) of Acacia karroo Hayne, analysed by GC-MS, shows that hexanal (10.67%) and ß-ionone (9.74%) were dominant in the dried leaves, β-pinene (14.30%), and (Z)-2-Hexen-1-ol (10.21%) in the fresh leaves while Octacosane (10.59%) and phytol (23.38%) were dominant in the dry and fresh stem respectively. The anti-inflammation ability of these oils after an albumin-induced inflammation on wistar rats, shows a significant effect at the 1st h of treatment with a significance of P< 0.01 for all part plants, while the fresh leaves shows further inhibitory activities at the 2nd h of analysis. Silver nanoparticles (AgNPs) were successfully synthesized from AgNO3 through a green route using the aqueous extract (hydrosols) of Acacia mearnsii De Wild and Acacia karroo Hayne as reducing agent and as well as capping agent. The Acacia-mediated AgNPs were characterized with the use of UV-vis absorption spectroscopy, Fourier Transform Spectroscopy (FT-IR), Transmission electron microscope (TEM), Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDX), and X-ray Diffractometry (XRD). A spherical, 10-40 nm diameter silver nanoparticles were synthesized with very low level of stability for the AMDS and the AKDS-AgNPs. In addition, nociceptive activity with a mice rat reveals higher inhibition at the neurogenic phase for the AKDS-AgNPs, while AMDS-AgNPs exhibited a high inhibition at the inflammatory phase. The potent anti-inflammatory activity of essential oils of A. mearnsii De Wild and A. karroo Hayne hereby confirmed its traditional use in treating various inflammatory diseases, while the inflammatory studies on the synthesized AgNPs reveals a very active compound which can be used as a potent opioid or non-steroidal anti-inflammatory drug (NSAID).
  • Full Text:

Nutritional value and cultivation requirements of Cleome Gynandra: a wild vegetable growing in the Eastern Cape Province, South Africa

  • Authors: Sowunmi, Linda Ifeanyichukwu
  • Date: 2015
  • Subjects: Ethnobotany -- South Africa -- Eastern Cape Vegetables -- South Africa -- Eastern Cape Nutrition -- South Africa -- Evaluation
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10353/2600 , vital:27907
  • Description: South Africa has wide ranges of plants among which are leafy vegetables growing in the wild. These wild vegetables have been reported to have high nutritive and medicinal potentials. Yet, there is still high prevalence of malnutrition and micronutrients deficiencies among the low income bracket of the population. Effective utilization of wild vegetables has been proposed as part of the solutions to address the problem of dietary deficiencies among the populace. Their importance is mainly as relish to accompany and complement starch based diets. They are also known to serve as supplements for food which have the potential to improve the health status of its consumers in many rural communities. Cleome gynandra L. (Capparaceae) is one of the underutilized species mentioned during asurvey conducted in Nkonkobe municipality of the Eastern Cape Province, South Africa. The plant is an erect annual herb with alternate, palmately compound leaves and its petals are white, pink or lilac. It grows as a weed in this part of the Province and is usually gathered from the wild for food and medicine. It is commonly found on wastes land, road sides and on grass lands. Therefore, this research work was designed to contribute to the possible domestication of this wild vegetable in order to explore the nutritive and therapeutic potentials which would broaden the food base in the Eastern Cape Province. The ultra-micromorphological features of plants have become an essential tool in proper identification and authentication of several plant species. In the light of this, the micromorphology of Cleome gynandra was examined to reveal the micro-morphological characters of the plantand to determine if micro and macro mineral elements are present using energy dispersive x-rays. The present study revealed the epidermal cells of the leaves to be asymmetric in shape with undulating cell walls having four subsidiary cells around the stomata. The leaves have anomocyctic stomata which are more distributed in the abaxial surface than the adaxial surface. The mean length and width of the guard cells in the abaxial surface are 0.09 ± 0.01 mm and 0.08 ± 0.01 mm respectively while that of adaxial surface are 0.1± 0.01 mm and 0.07 ± 0.01 mm respectively. The energy dispersive x-rays (EDXS) micro-analysis of the leaf revealed the presence of phosphorus, manganese, iron, calcium, sodium, magnesium, potassium and zinc as the major constituents of the crystal deposits present in the stomata pores and the mesophyll. C. gynandra was collected from the wild and analysed for its mineral and proximatecomposition using standard analytical methods. The plant showed high levels of sodium, iron, zinc, calcium and potassium while many other macro and micro minerals were moderately present. Amongst the proximate factors investigated, moisture content was found to be 82.1% while crude fibre and protein contents were 39.9 percent and 31.03 percent respectively. Vitamin C was also high (345.3 mg/100g). The anti-nutrients compositions revealed low concentrations of oxalate (7.4 ± 0.4) and phytate (0.6 ± 0.0) mg/100g. The study revealed high nutritive value of the species growing naturally from the wild. Interest in the phenolic compounds has greatly increased recently because these compounds have been implicated in suppressing the risk of degenerative diseases in humans. The pharmacological properties of plants may be related to their antioxidant capacities and hence there was need to investigate the antioxidant potential using aqueous, ethanolic and acetone extracts of different parts of C. gynandra. The quantities of phenols, flavonoids and flavonols were significantly higher (p < 0.05) in both aqueous and ethanol extracts of the leaf while the concentration of proanthocyanidins was higher in the aqueous stem extract compared to other plant parts. The aqueous extract of the different parts exhibited better ABTS, reducing power and NO radical scavenging abilities than ethanol extract.
  • Full Text:

Phytochemical, antibacterial and pharmacological investigations of Clausena Anisata (Wild). Hook : bone of the medicinal plants used for traditional treatment of "tuberculosis" in Eastern Cape, South Africa

  • Authors: Lawal, Ibraheem O
  • Date: 2015
  • Subjects: Traditional medicine--South Africa--Eastern Cape Tuberculosis--Treatment--South Africa--Eastern Cape Mycobacterial diseases--South Africa--Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , Ethnobotany
  • Identifier: http://hdl.handle.net/10353/11828 , vital:39110
  • Description: Clausena anisata (Willd) Hook, is the only species out of the 15 species of the genus found in the African continent and is regarded as a threatened species in this area of Southern region of Africa. Its distribution spread across Africa to south-east Asia. C. anisata has a wide range of ethno-pharmacological importance. Despite the numerous studies on the pharmacological profile of the plant, there is still dearth of scientific literature on the foliar micro-morphology of this valuable medicinal plant. The morphorlogical structure of the leaves of C. anisata was examined under Light Microscopy (LM), Scanning Electron Microscopy (SEM) and Energy Dispersive x-ray Spectroscopy (EDS) following standard procedures. LM indicates the types of stomata of the leaves (amphistomatic). SEM revealed the presence of the whip like trichomes with its uniqueness to the plants. EDS showed the chemical composition of the foliar appendages which indicated the presence Ca, Mg, S, and Fe. The indication of the elements could probably be helpful in the herbal drug regulation based on the mineral composition and in return reduced herbal drug toxicity.
  • Full Text:

Supporting the implementation of alternatives to corporal punishment in the Eastern Cape secondary schools : towards a framework for school management teams and teachers

  • Authors: Kalipa, Velelo Clifton
  • Date: 2015
  • Subjects: School discipline -- South Africa -- Eastern Cape Corporal punishment of children -- South Africa -- Eastern Cape Rewards and punishments in education
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/5664 , vital:29359
  • Description: Alternative to corporal punishment in schools is a worldwide practice. Most countries have banned the use of corporal punishment in schools and have promulgated laws and adopted policies aiming to enforce the practice of alternative to corporal punishment. South Africa is one of the countries that have introduced policy on alternatives to corporal punishment. However, this policy does not provide details on how School Management Teams (SMTs) and teachers should support the implementation of alternatives to corporal punishment; as a result, schools end up having different approaches in as far as implementing alternatives to corporal punishment is concerned. There is also a serious problem of indiscipline in schools and this has since attracted growing attention of researchers in South Africa and the whole world. There are serious offences by learners in schools which range from serious criminal ones such as drug abuse, assaults, theft, murders and rapes to less serious ones such as truancy, incomplete projects, absenteeism and lateness, dodging and bunking of classes in schools. This study therefore sought to investigate how SMT and teachers support the implementation of alternatives to corporal punishment in schools. This was a multi case study of four secondary schools in the King Williams Town Education District which was conducted through qualitative research approach. Interviews and documentary analysis were used to collect data and a total of 16 participants (four principals, four SMT members and eight teachers) were selected. From the data, it emerged that some teachers were fixed in using corporal punishment to discipline learners in schools. The data also showed that the alternatives to corporal punishment (ATCP) policies were inconsistently applied as schools had different approaches in as far as how ATCP is implemented and that some schools had no ATCP policies at all. It also emerged from the data that school leadership was a problem in as far as supporting the implementation of ATCP in schools as in some schools the issues of disciplining learners was centralised in the principal’s office. It also became clear that the majority of participants did not understand the national policy on ATCP. There were no indications of parental involvement in the implementation of ATCP in schools. It can be concluded that the channels of communication among principals, SMTs, teachers with regards to the implementation of ATCP was problematic as there were no clear roles as to how each of these officials should implement ATCP. Some teachers still perceived the ATCP as unsuitable for maintaining discipline in rural schools and their discipline strategies were still characterized by punitive measures which border on corporal punishment. School discipline was not seen as a societal matter where other relevant stakeholders could play a pivotal role in learner discipline. This had a negative impact on the school discipline. Learners had no responsibility on maintenance of positive school atmosphere as they were not in any way part taking in the maintenance of discipline in schools. This study therefore recommends a comprehensive framework for the implementation of ATCP that will give details on the roles of SMTs and teachers in the implementation of ATCP in schools. It is recommended that this framework be inclusive of parents and other community stakeholders who would give different perspectives on the implementation of ATCP in schools as education is a societal matter. It is also recommended that more research be conducted that will deal with urban schools and on the involvement of parents and other stakeholders in the implementation of ATCP.
  • Full Text:

Synthesis, characterization & application of visible light responsive nitrogen doped Tio2 and copolymer-grafted asymmetric membranes with ozonolysis for water treatment

  • Authors: Mungondori, Henry H
  • Date: 2015
  • Language: English
  • Type: Thesis , Doctoral , PhD (Chemistry)
  • Identifier: vital:11350 , http://hdl.handle.net/10353/d1020257
  • Description: The use of titanium dioxide for the photo-catalytic removal of organic, inorganic, and microbial pollutants from natural water and wastewater has been considered a very promising technique. The aim of this study was to prepare nitrogen doped titanium dioxide, immobilize it on asymmetric polymeric membranes of poly (methacrylic acid) grafted onto poly (vinylidene difluoride) (PVDF) blended with poly (acrylonitrile) (PAN), and evaluate the photo-catalytic, antimicrobial, and antifouling properties of the membranes. Nitrogen doped titanium dioxide (N-TiO2) nano-particles were prepared by a low temperature sol gel synthesis technique. The modification of TiO2 with nitrogen allows photo-sensitization of the photo-catalyst towards visible light utilization. The N-TiO2 nano-particles were characterized by fourier transform infrared spectroscopy (FT-IR), scanning x-ray photoelectron spectroscopy (SXPS), X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS), Brunauer Emmett Teller (BET) surface area analysis, and transmission electron microscopy (TEM). The characterizations revealed the presence of the expected functional groups and confirmed successful doping and that the product was visible light responsive. Novel poly (methacrylic acid) grafted onto poly (vinylidene difluoride)/ poly (acrylonitrile) (PMAA-g-PVDF/ PAN) asymmetric membranes were prepared by the dry-wet phase inversion technique. The poly (methacrylic acid) (PMAA) side chains where grafted onto an activated PVDF backbone by reversible addition fragmentation chain transfer (RAFT) polymerization. The photo-catalytic membranes were generated by blending N-TiO2 with the polymer solution before casting the membranes. The membranes were characterized by FT-IR, nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). FT-IR and NMR analyses confirmed successful grafting of MAA chains onto PVDF while SEM confirmed the successful preparation of membranes with asymmetric structure. The efficacy of the photo-catalytic asymmetric membranes was evaluated on the removal of herbicides from synthetic water. Bentazon was easily degraded while atrazine and paraquat were recalcitrant and proved difficult to degrade. The best results were observed with 3 % N-TiO2-PMAA-g-PVDF/ PAN asymmetric membranes on the photo-degradation of bentazon, atrazine and paraquat in water. Significant enhancement in the photo-degradation of the three herbicides was observed when photo-catalytic degradation was coupled with ozonation. Liquid chromatography-mass spectrometry (LC-MS) analysis confirmed the presence of a degradation by-product during the photo-catalytic degradation of bentazon. The photo-catalytic membranes were also evaluated on the photo-catalytic reduction of heavy metals Pb2+ and Fe3+ in water, and the best results were obtained using 1 % N-TiO2-PMAA-g-PVDF/ PAN and 1 % N-TiO2-PAN asymmetric membranes. All prepared photo-catalytic membranes where capable of completely inactivating E. coli ATCC 8739 within 120 minutes of exposure and inactivation rate increased with increasing N-TiO2 photo-catalyst loading. However, there was an indication from the results obtained that N-TiO2 supported on PMAA-g-PVDF/ PAN showed a higher inactivation rate of E. coli ATCC 8739 compared to N-TiO2-PAN and N-TiO2-PVDF membranes. The 1 % N-TiO2-PMAA-g-PVDF/ PAN membranes gave the highest pure water flux (421.83 L/m2h). This increase (PVDF = 30.50 L/m2h, PAN = 73.85 L/m2h) in pure water flux is owedb to PMAA grafting as well as addition of N-TiO2. These modifications resulted in an increased membrane surface hydrophilicity, which promoted permeation of pure water through the membrane structure. A high bovine serum albumin (BSA) rejection (76.5 %) was noted and can be attributed to steric hindrance brought about by PMAA side chains which prevented the bulky BSA molecules from attaching to the membrane surface for PMAA-g-PVDF/ PAN membranes. However, the supporting porous sub-layer of an asymmetric membrane seemed to play a very important role in the overall permeability of a membrane. PVDF membranes are highly hydrophobic hence they gave a very low pure water flux.
  • Full Text:

The effects of distance travelled, lairage duration and animal-related factors on pre-slaughter stress indicators, carcass characteristics, nanostructure and technological properties of beef

  • Authors: Chulayo, Amanda Yucca
  • Date: 2015
  • Subjects: Slaughtering and slaughter-houses -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape , Nanostructured materials -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD (Animal Science)
  • Identifier: vital:11835 , http://hdl.handle.net/10353/d1021275 , Slaughtering and slaughter-houses -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape , Nanostructured materials -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape
  • Description: The main objective of the current study was to determine the effect of distance travelled (DT), lairage duration (LDhr) and animal-related factors (animal class, breed, sex) on pre-slaughter stress indicators, carcass characteristics, nanostructure and technological properties of beef. The study was conducted in an Eastern Cape abattoir under the Buffalo City District Municipality. Six genotypes of cattle (Beefmaster, Bonsmara, Brahman, Holstein-Friesian, Non-descript and Nguni) brought for slaughter at the abattoir on different days were used in the study. Slaughter weight (SWT), warm and cold carcass weight (WCW and CCW), fatness and conformation of each animal were measured and recorded. Representative samples of blood plasma and meat quality from the Muscularis thoracis et lumborum (LTL) were collected at slaughter and 24 hours after slaughter, respectively. Heat shock proteins 70kDa (HSPA1A), glucose (GLU), cortisol (CORT), creatine kinase (CK) and lactate dehydrogenase (LDH) were determined from the blood plasma. The representative LTL muscle was used to determine ultimate pH (pHu), lightness (L*), redness (a*), yellowness (b*), meat temperature (Tm), Warner Bratzler Shear Force (WBSF) and histological structure of beef. There were significant effects of distance on pHu, Tm, a*, b*, TL%, CK and LDH. Pearson correlations were observed between distance travelled (DT), creatine kinase (CK), lactate dehydrogenase (LDH), ultimate pH (pHu), colour coordinates (L*, a* and b*) and Warner Bratzler Shear Force (WBSF). Principal component analysis (PCA) revealed that the 1st (pHu), 2nd (Tm) and 3rd (L*) principal components were the critical meat quality attributes. Positive relationships between carcass weights and beef quality characteristics for bovine cattle where the cumulative percentage of the first six principal component`s (PC`s) (SWT, WCW, CCW, DP, pHu and Tm contributed to 93.4 % of the total variance. Significant correlation coefficients between DT (r = 0.15), LDhr (r = 0.29), Ta (r = -0.52), Tm (r = 0.26), L* (r = 0.33), a* (r = 0.32) and WBSF (r = -0.49) were observed. Meat from Brahman (BR), Non-descript (ND) and Nguni (NG) cows had visible skeletal muscle fibres which were thin and long indicating improved tenderness of beef. Exposing animals to longer hours of transportation did not only reduce glucose levels but also increased the expression of HSPA1A and levels of cortisol. The CK and LDH were not related to beef quality. Therefore, CK and LDH can be used as indicators of animal welfare in slaughter cattle but cannot be used to predict the quality of meat. Bulls were the heaviest, although heifers had the highest dressing percentage than cows. Furthermore, the nanostructure of beef indicated that heifers had the best muscle fibres, sarcomere length and visible intercalated discs. The observed nanostructures of Nguni genotype are an indication of tender meat. Beef from heifers of Nguni had visible and tender meat with traces of intramuscular fat while males had shorter sarcomere length and tougher meat.
  • Full Text:

The process of naturalisation of refugees under international and South African law and its implications for human rights

  • Authors: Masumbe, Paul Sakwe
  • Date: 2015
  • Subjects: Naturalization -- Africa Human rights -- Africa Refugees -- Legal status, laws, etc. -- Sout -- Africa
  • Language: English
  • Type: Thesis , Doctoral , LLD
  • Identifier: http://hdl.handle.net/10353/5608 , vital:29351
  • Description: This study seeks to examine the naturalisation of refugees under international law with specific focus on the South African refugee system. The universalised nature of human rights and the difficulties of refugees finding new roots in host states form the basis of this study. This study takes a closer look at the South African refugee system and the path to naturalisation of refugees. It identifies policy and legal gaps in the process of naturalisation of refugees and argues that the practice as it stands today, fundamentally abuses the rights of refugees and questions South Africa’s good faith in meeting its international obligations under the 1951 Refugee Convention. It argues further that the biopolitical philosophy upon which South African citizenship is anchored is itself a hindrance to the realisation of efforts aimed at naturalising refugees and their descendants. The research methodology used in this study is non-empirical. This is so because the study is based on available data, information already available in print or on the internet. The study attempts to accomplish the above by undertaking an in-depth analysis of the history of refugees, the current position of naturalisation under international law, and identifies the inherent challenges. In the South African context, the study makes use of extensive statutory, constitutional and case law materials to justify that the current treatment of refugees in their quest for naturalisation is indefensible within the context of a human rights-based approach and the dictates of the Constitution. This study concludes by making recommendations that would help close the legal and policy gaps that obtain presently. These include amendments to the Refugees, Immigration and Citizenship Acts and strengthening policy implementation at the DHA. It is hoped that the recommendations will strengthen and evolve a human rights culture and bring refugee, immigration and citizenship laws in line with the Constitution. It will also pave the way for a more just and peaceful South Africa as she strives to meet her obligations under regional and international law.
  • Full Text:

The role of academic middle managers in the planning and implementation of curriculum change in private higher education institutions in Botswana

  • Authors: Rudhumbu, Norman
  • Date: 2015
  • Subjects: Universities and colleges -- Botswana -- Administration Education, Higher -- Aims and objectives -- Botswana Curriculum planning -- Botswana
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/2979 , vital:28214
  • Description: The purpose of the study was to examine the role of academic middle managers (AMMs) in the planning and implementation of curriculum change in private higher education institutions in Botswana. This study employed a mixed methods research approach which utilised a structured questionnaire and a semi-structured interview guide to gather data on AMMs‟ role in the planning and implementation of curriculum change in PHEIs in Botswana. SPSS version 21 was used for analysing quantitative data while thematic analysis was used for analysing qualitative data on the role of AMMs in the planning and implementation of curriculum change in PHEIs. The study showed that the role of AMMs in the planning and implementation of curriculum change in PHEIs was too complex and demanding because they spent most of their time on daily administrative routines instead of on core academic activities such as planning and implementing curriculum change in their departments. The AMMs in the PHEIs under study operated more like managers in academic departments than academics in management. As a result the study showed that AMMs faced more challenges than opportunities in their planning and implementation of curriculum change in PHEIs. The major challenges AMMs faced in the planning and implementation of curriculum change were a highly controlled and strict work environment, role conflict, lack of autonomy, role strain and heavy workloads which limited the time AMMs spent on the core business of managing curriculum change in their departments. The study also highlighted some of the strategies albeit a few, which, despite the numerous challenges AMMs faced, are used to try and make the planning and implementation of curriculum change by AMMs was to some extent successful. The study provided insight on the influence of AMMs biographical characteristics as well as the influence of AMM job requirements (such as having a detailed job description and having authority over curriculum matters) on how AMMs enacted their role in curriculum change. Based on the results of the study, a model to assist AMMs in the effective planning and implementation of curriculum change was proposed.
  • Full Text:

Towards a changing context and performance practice of mbira dzavadzimu music in Zimbabwe

  • Authors: Chipendo, Claudio
  • Date: 2015
  • Subjects: Mbira music -- Zimbabwe Shona (African people) -- Music
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/6357 , vital:29588
  • Description: Mbira dzavadzimu music and performance practice has been in existence since the pre-colonial era. It played a crucial role in ritual and non-ritual activities of the Shona people of Zimbabwe. However, political, social and global influences as well as technological advancement have resulted in change of context and performance practice. Unfortunately, these have not been recorded for future generations. The major aim of the study is therefore to examine the change of context and performance practice of mbira dzavadzimu in Zimbabwe. This was achieved by reviewing mbira dzavadzimu music and performance practice within the modern setting of dandaro. I looked at change from a theoretical lens of the theory of diffusion, syncretism and mediatisation. The study was in the qualitative form superimposed on some case studies. Unstructured interviews, participant and non-participant observations were the main instruments used to collect data from both traditional and modern mbira performances. Data was also collected from museums, archives, radio and television stations. The study established that the changes in context and performance practice of mbira dzavadzimu in Zimbabwe were to a larger extent due to foreign influences such as colonialism, the coming of missionaries, modernisation, urbanisation, commercialisation, mediatisation, the use of modern technology and institutionalisation. Due to the aforementioned influences, the environmental settings, the change of context from sacred to secular, the relationship with ancestral spirits, musical practices, performance situations and quality of sound, have been modified and adjusted in response to the influences of the globalised world’s ever changing audience and performance space. In short, this has resulted in a shift of mbira performances from its traditional to modern settings, from the village to the city and onto the international scene with a new performer-audience setting. Various innovations were carried out on the instrument and its music as a result of the advent of modern technology. The use of microphones, modern amplification systems, recording studios, radio and television broadcast, audio and video cassettes, CDs, DVD, teaching of the instrument using audio and video instructional models and the use of internet sites in learning how to play mbira dzavadzimu and other instruments have become a reality. It has been evident from the study that urban and rural areas take up change in different ways and that in the former change is more pronounced than in the latter. Urban area communities are more “developed” than their rural counterparts because the former are more exposed to technological influences and the commercialisation of music. The study has also established that Zimbabwean mbira music is a good example of modern transculturality. The instrument and its music have played a major role in breaking down cultural boundaries and bringing the people of the world together for purposes of performing on the instrument. From the findings of this study, I attribute most of the changes to technologisation, for most of the changes that have taken place on mbira dzavadzimu were a result of the highly technologised way of life Zimbabweans now lead.
  • Full Text:

Aggregate stability, crust formation, steady state infiltration and mode of seedling emergence in soils with various texture and mineralogy

  • Authors: Nciizah, Adornis Dakarai
  • Date: 2014
  • Language: English
  • Type: Thesis , Doctoral , PhD (Crop Science)
  • Identifier: vital:11871 , http://hdl.handle.net/10353/d1015539
  • Description: The general objective of this study was to quantify the interactive effects of soil texture and mineralogy on soil crusting, infiltration and erosion and the subsequent effects on maize seedling emergence and early development using soils collected from 14 ecotopes in the Eastern Cape Province. The specific objectives were to determine; i) particulate organic matter, soil texture and mineralogy relations, ii) aggregate stability and breakdown mechanisms as affected by soil texture and organic matter, iii) crust formation and steady state infiltration, iv) rainfall pattern effects on crusting, infiltration and erodibility and v) rainfall intensity effects on crusting and mode of seedling emergence. Particulate organic matter (POM) was fractionated into litter POM, coarse POM and fine POM. Both total soil organic matter (SOM) and the POM in each fraction were determined using the weight loss on ignition procedure. Most ecotopes were either sandy loam or sandy clay loam and primary minerals especially quartz dominated the soil mineralogy. The clay content was significantly related to the total SOM (r = 0.78), hematite (r = 0.83) and quartz (r = -0.74). Aggregate stability was determined following methods described by Le Bissonnais (1996) i.e. fast wetting (FW), slow wetting (SW) and wet stirring (WSt). Aggregate breakdown followed the order; slaking < mechanical breakdown < micro-cracking for most ecotopes except Lujiko Leeufontein and Amatola Jozini where SW and WSt resulted in the least MWD respectively. Aggregate stability was significantly correlated to POM only for FW and SW and only positive but not significant for WSt. To study crust formation, aggregate sizes <2, 2 to 3, 3 to 5 mm were exposed to 60 mm hr-1 simulated rainfall. Sieving structural crusts, ~0.2 to ~0.8 mm thick with a surface layer of loose grains overlying a thin plasmic layer, formed in all ecotopes. Crusts with strengths between 0.25 and 3.42  10-4 kg m-2 developed on the <2 mm compared to <2.23  10-4 kg m-2 in the >2 mm aggregates. The reverse occurred in Alice Jozini, which had relatively low clay content of 120 g kg-1. Two significantly different groups of the SSIR were observed. The SSIR was between 1.24 and 3.60 mm hr-1 in the group of ecotopes dominated by primary minerals and relatively lower clay content. In the second group, consisting one ecotope dominated by kaolinite and relatively higher clay content, the SSIR was 15.23 mm hr-1. Rainfall pattern i.e. rainfall applied either as an eight minute single rainstorm (SR) or four-two minute intermittent rainstorms (IR) separated by a 48 h drying period significantly (p < 0.05) affected crust strength, SSIR and erosion. The IR resulted in higher crust strength and SSIR than SR. The effect of rainfall pattern on SSIR was mostly influenced by the primary minerals namely, quartz. Three maize seeds of equal size were planted in plastic pots, pre-wetted by capillary action and then subjected to simulated rainfall at three intensities for 5 min. Rainfall intensity (30, 45 and 60 mm h-1) significantly (P < 0.05) affected crust strength and mean emergence day (MED) but not emergence percentage (EMP) and shoot length (P > 0.05). The 60 mm h-1 rainfall intensity resulted in the highest crust strength and MED.
  • Full Text:

Alternative methods used by small-holder farmers to control ticks and bovine dermatophilosis and the impact of a changing interface of Amblyomma ticks on dermatophilosis in Zimbabwe

  • Authors: Ndhkovu, Daud Nyosi
  • Date: 2014
  • Subjects: Ticks -- Control -- Africa, Southern , Dermatophilosis
  • Language: English
  • Type: Thesis , Doctoral , PhD (Animal Science)
  • Identifier: vital:11830 , http://hdl.handle.net/10353/d1019764 , Ticks -- Control -- Africa, Southern , Dermatophilosis
  • Description: This study was carried out to document the ethno-veterinary plants and non-plant remedies that farmers used to control dermatophilosis and ticks, and validate these in vitro and in vivo, as well as determine how the interface of Amblyomma variegatum and A. hebraeum affected the epidemiology of bovine dermatophilosis at selected small-holder areas in North-West Zimbabwe. A structured questionnaire survey was used to collect information on the control methods used by farmers for the control of bovine dermatophilosis and ticks. A total of 39 plants were used by farmers for various diseases, eleven of these plants were used for the control of dermatophilosis while three were for tick control. Across the study sites, dermatophilosis was controlled using eleven plants. Among these plants; six plants; Cissus quadrangularis, Catunaregan spinosa, Pterocarpus angolensis Carica papaya, Manihot esculenta and Blumea decurrens which were frequently used were selected for further studies. In vitro and in vivo studies were conducted to validate the efficacy of these plants. The minimum inhibitory concentration and bactericidal concentration assays were used for the in vitro validation of C. quadrangularis, C. spinosa and P. angolensis. Dermatophilus congolensis was more sensitive to P. angolensis average MIC = 0.63 mg/ml than to C. quadrangularis average MIC = iii 1.25 mg/ml and C. spinosa average MIC = 2.08 mg/ml. Cissus quadrangularis was selected for in vivo studies as this plant was the one most frequently used by farmers. Its therapeutic efficacy was compared to conventional antibiotics that farmers used to treat dermatophilosis infection. In the in vivo trials C. quadrangularis did not lead to appreciable reduction in clinical disease compared to the conventional drugs. The larval packet assay was the in vitro assay used to validate the efficacy of Carica papaya, Manihot esculenta and Blumea decurrens against larvae of A. hebraeum and Rhipicephalus appendiculatus. Manihot esculenta at 20 % w/v exhibited the highest larvicidal activity against R. appendiculatus. In the in vivo study, efficacy of the plants were investigated on naturally tick-infested cattle. Mannihot esculenta exhibited the largest tick load reduction compared to the other two plants but its performance was lower than that of conventional acaricides. The effect of A. variegatum and A. hebraeum on bovine dermatophilosis was investigated by evaluating how the presence or absence of these ticks and other herd level risk factors predicted clinical dermatophilosis and its prevalence at herd level. A structured questionnaire survey was carried out to collect data on potential risk factors. At the same time, cattle were physically examined for the presence of bovine dermatophilosis, according to a pre-defined case definition, and presence or absence of Amblyomma ticks was also recorded. The multivariable binary logistic model was developed with disease status as outcome, tick presence and infestion and herd level risk factors as predictors. Of the herds examined clinical bovine dermatophilosis was detected in 45% (84/185; 95% CI: 38.2, 52.6%) of them. Herds infested with Amblyomma variegatum were associated with higher odds (OR= 6.8; iv 95% CI: 1.71, 27.10) of clinical dermatophilosis while the association was not significant (P > 0.05) in A. hebraeum infested herds. It was concluded that management practices aimed at movement and tick control would help reduce the prevalence of clinical dermatophilosis in herds.
  • Full Text:

An analysis of the relationship between bank efficiency and access to banking services in South Africa

  • Authors: Maredza, Andrew
  • Date: 2014
  • Language: English
  • Type: Thesis , Doctoral , Doctor of Administration (in Public Administration)
  • Identifier: http://hdl.handle.net/10353/910 , vital:26508
  • Description: The primary objective of this study is to investigate the nature of the relationship between bank efficiency gains and access to banking services in South Africa. The importance of making such an enquiry arises from the fact that various studies have identified access to financial services as an important vehicle for lifting the poor out of poverty. In particular, there is concern that banks` appetite for better scores on efficiency has the potential of reducing access to services for consumers particularly the low-income clients. The study attempted to answer two central research questions: Firstly, does the quest for banks to improve efficiency preclude access to banking services for some group of consumers? Secondly, do bank efficiency gains necessarily translate to improved accessibility to banking services? The researcher applied a two-stage methodology approach. In the first stage, the Hicks-Moorsteen aggregator functions were used to generate and decompose total factor productivity (TFP) into several efficiency measures for a panel of eight South African banks. First stage results revealed that the average banking sector total factor productivity efficiency (TFPE) was 59 percent implying that the observed TFP was 41 percent short of the maximum TFP possible using the available technology. A further comparison of performance revealed that large banks were better performing than small banks in terms of TFPE. Apart from estimating and decomposing TFP indices we needed to determine if there was a statistically significant change in the TFPE of South African banking system as a result of the global financial crisis. A general analysis of the generated scores showed that TFPE clearly decreased during 2008-2009, the period that coincided with the global financial crisis. We then used the Fixed Effects Model (FEM) in the second-stage analysis to examine the link between banking sector TFPE and access. The FEM was utilised to take account of bankspecific heterogeneity. The obtained results indicated existence of a positive and significant relationship between banking efficiency and access to banking services. This study suggests that banking sector efficiency plays a crucial role in promoting access to bank services in South Africa. We therefore underscore the need for all banks to attain and maintain high efficiency in order to augment government efforts towards improving accessibility for the unbanked South African people. We also found evidence similar to that reached by Kablan (2010) that an increase in the rural population is associated with a reduction in access to bank services. From this result, we speculated that banks are somewhat biased against providing their services to the general rural populace. Since the rural-population variable exerted the greatest marginal impact on access we suggested that perhaps investment in rural infrastructure would help broaden access and so improve financial inclusion on a larger scale. Finally we also investigated the link between banking sector efficiency and unemployment in South Africa. Of paramount importance in the second stage analysis was that we found a negative and significant association between banking sector efficiency and unemployment indicating that employment is influenced, inter alia, by the efficiency with which banks operate.
  • Full Text:

An integrated approach for the delineation of arable land and its cropping suitability under variable soil and climatic conditions in the Nkonkobe municipality, Eastern Cape, South Africa

  • Authors: Manyevere, Alen
  • Date: 2014
  • Subjects: Soils -- Classification -- South Africa -- Eastern Cape , Soil degradation -- South Africa -- Eastern Cape , Ethnoscience -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD (Soil Science)
  • Identifier: vital:11965 , http://hdl.handle.net/10353/d1019856 , Soils -- Classification -- South Africa -- Eastern Cape , Soil degradation -- South Africa -- Eastern Cape , Ethnoscience -- South Africa -- Eastern Cape
  • Description: Arable crop production in Nkonkobe Municipality is low due to abandonment of potentially productive land and low productivity of the cultivated land. Little attention has been given to farmers perspectives with regards to crop production and land abandonment. Understanding the relationships of indigenous knowledge systems, where local approaches to soil classification, appraisal, use and management and land evaluation, and scientific approaches could be important for the effective use of available soil resources while avoiding those resources that are vulnerable to degradation. In addition, the interactions between soil factors and climate could be useful in understanding the erodibility of soils. The intergration of scientific research and indigenous knowledge systems could help in the identification and delineation of high potential land and on crop suitability evaluation. The objectives of the study were: (i) to determine farmers‟ perspectives with regards to land utilisation and abandonment, constraints on crop production and crop preferences, (ii) to integrate and compare indigenous knowledge systems with scientific approaches of soil classification and potential, (iii) to determine the effect of climate and soil factors on erodibilities of soils in the Municipality (iv) to delineate arable land and evaluate its suitability for maize, potato, sorghum and cowpea under rainfed agriculture. Using semi-structured and open-ended interviews, information on limitations to crop production, cropping preferences, indigenous soil classifications, cropping potential ratings and erosion was captured. Descriptive and correlation statistics were used to analyse farmers‟ responses. The information was later used for a pilot participatory mapping and the determination of the agricultural potential of the soils in three selected villages of the Municipality. Field boundaries of soil texture, colour, depth, and slope position were captured using global positioning systems (GPS). The relationship between the degree of erosion and soil and slope factors was analysed by step-wise regression. Crop suitability for rainfed agriculture was done using the FAO guidelines for Land evaluation for rainfed agriculture. The spatially referenced crop suitability classes were produced by applying the Law of Limiting Combinationusing GIS Boolean Logic. The major biophysical factors, affecting crop production and land utilisation were soil degradation and low and erratic rainfall, while other factors included lack of farming equipment and security concerns. Maize, spinach and cabbage were the main crops grown, with maize sorghum and wheat the most abandoned crops. While it was difficult to accurately correlate indigenous classification with international scientific classification, the importance of colour, texture and soil depth for both classification and soil potential, suggests that some form of correlation is possible which enabled communication and other extension information to be conveyed. The shallow and stony soil (urhete) correlated well with the Leptosols in World Reference Base (WRB) or Mispah and shallow Glenrosa soils in the South African system. The red structured clays (umhlaba obomvu) matched the Nitisols in WRB or Shortlands in the South African system. The non-swelling black clayey soils (umhlaba omnyama) matched soils with melanic A horizons in both the WRB and South African soil classification systems. The dongwe and santi soils developed in alluvial sediments belonged to the Dundee, Oakleaf or Augrabies soils in the South African classification system and fluvisols or Cambisols in the WRB system. There was good agreement between farmers assessment of the cropping potential and scientific approaches but scientifically high potential red soils were rated lowly by the farmers due to difficulties in management caused by shortages of farm machinery, especially under dryland farming. Overall, the soil factors affecting erosion were influenced largely by climate, while parent material was also important. Climate had a dominant influence on soil factors most notably fine sand and very fine sand fractions and exchangeable sodium percentage being more important on soil forms occurring in arid and semi-arid climate and less in the sub-humid and humid areas, where clay mineralogy, particularly kaolinite and sesquioxide dominated. Dolerite derived soils were the most stable and should be given the highest priority for cropping development while mudstone and shale derived soils had a lower cropping potential. While slope gradient and length had some effect on soil erosion in arid and semi arid environments its influence was generally overshadowed by soil factors especially in humid zones. Cow pea and sorghum were the most adapted crops in the region while potato and maize were marginally suitable under rainfed agriculture. The study revealed that most adapted crops were not necessarily the most preferred crops by the farmers. A small percentage of the land was delineated as arable and therefore optimisation of this available land should be prioritized.
  • Full Text:

Assessment of the anti-Listerial properties of Garcinia kola (Heckel) seeds

  • Authors: Penduka, Dambudzo
  • Date: 2014
  • Subjects: Microbial sensitivity tests , Garcinia , Medicinal plants , Traditional medicine
  • Language: English
  • Type: Thesis , Doctoral , PhD (Microbiology)
  • Identifier: vital:11278 , http://hdl.handle.net/10353/d1015527 , Microbial sensitivity tests , Garcinia , Medicinal plants , Traditional medicine
  • Description: A follow-up of traditional medicinal plants uses is an important tool in highlighting their therapeutic potentials, as they have been found to be a source of a wide range of bioactive compounds that can be used as base compounds for new pharmaceutical drugs. This study therefore focuses on assessing the anti-Listerial properties of the seeds of Garcinia kola (Heckel) plant, which is a traditional medicinal plant of west and central African origin, and was and is still used to traditionally treat several ailments. Four different solvents crude extracts of the seeds were assessed for their anti-Listerial activities in-vitro, against a panel of 42 Listeria bacteria, which included Listeria monocytogenes, Listeria ivanovii and Listeria grayi species. At 10 mg/ml concentration the aqueous extract had activity against 29% of the test isolates while the other three crude extracts namely dichloromethane, n-hexane and the methanol extracts had activity against 45% of the test bacteria. The minimum inhibitory concentration (MIC) ranges of the extracts were 0.079-0.313 mg/ml for the dichloromethane extract; 0.079-0.625 mg/ml for the n-hexane extract; 0.157-0.625 mg/ml for the methanol extract; and 10->10 mg/ml for the aqueous extract. The minimum bactericidal concentration (MBC) ranges of the extracts were 0.625–10 mg/ml for both the n-hexane and the dichloromethane extract; 5-10 mg/ml for the methanol extract; and those for the aqueous extract were above 10 mg/ml against all the susceptible Listeria isolates. The rate of kill analysis was then determined for the three most active crude extracts that is excluding the aqueous extract and it was assessed against four representative Listeria species namely L. monocytogenes (LAL 8), L. grayi (LAL 15), L. ivanovii (LEL 30) and L. ivanovii (LEL 18). All the three extracts showed a general trend of being concentration and time dependent in their rate of kill profiles such that most bacteria cells were killed at the highest test concentration of 4× MIC value after the maximum exposure time of 2 h. The n-hexane, dichloromethane and methanol extracts were bactericidal against 4, 3 and 1 isolates out of the four test Listeria isolates respectively.
  • Full Text:
  • Disclaimer
  • Privacy
  • Copyright
  • Contact