Exploring the influence of a multiliteracies approach on Grade 11 Physical Sciences learners' sense making and dispositions towards graphs of motion
- Authors: Mwiiyale, Laina Natangwe
- Date: 2017
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/17605 , vital:22264
- Description: Namibian students perform poorly in Physical Sciences and the Physics component in particular (DNEA, 2013). The Namibian Senior Secondary Certificate (NSSC) Examiner's report (DNEA, 2014) also reveals that many Physical Science learners have difficulties demonstrating an understanding of basic physics required for working with kinematic graphs (graphical representation of motion). Kinematics is an important tool in understanding the motion of objects - whether translational, oscillatory or circular. In kinematics, the relationships between distance, displacement, speed, velocity or acceleration and time are represented in graphs of motion. In teaching the topic, using graphs can be an alternative to the use of abstract formulas, or formulas can be used along with graphical representations to facilitate student understanding (Behzak, 2006). This study explored the influence of the multiliteracies approach on grade 11 Physical Science learners' dispositions and sense making towards graphs of motion. The intervention being investigated is informed by the Pedagogy of Multiliteracies (PoM) framework by Cazden et al., (1996) with the focus on overt instruction, situated practice, critical framing and transformed practice using semiotic patterns of meaning, in conjunction with Vygotsky's (1978) social constructivism theory - particularly, its notion of mediation. This action research study employed the interpretive paradigm. Data were collected using a pre-test, stimulated recall interviews, lesson observations, a post-test and learners' reflections. Data were coded and the codes then categorized into different themes in order to answer the research questions. The findings of this study were that learners are better able to make sense of graphs of motions when a PoM approach is employed. Their dispositions towards graphs of motion also improved as a result of the PoM intervention, due to it enabling a better understanding of kinematics concepts. This study also contributed to the professional development of the researcher, particularly in terms of it contributing to a broader understanding of the research and possible usefulness of semiotic mediation in science education. Implications of the study include the possibility of including the PoM approach in science teacher education and training programme curricula.
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- Date Issued: 2017
Investigating adaptation strategies to climate change by smallholder farmers : evidence from, Lesotho
- Authors: Morahanye, Mokhantso Lilian
- Date: 2017
- Subjects: Climatic changes -- South Africa Farms, Small -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5807 , vital:29397
- Description: In Lesotho, agriculture is the dominant activity and involves crop and livestock production, range management and forestry activities. The current climatic variability in the country has caused decline in food production as result of increased dry spells, frequency of droughts and erratic rainfall. These climatic events are expected to have a significant impact on the livelihoods of the smallholder farmers. In combatting the harmful effects of climate change, smallholder farmers in Lesotho have employed various adaptation strategies based on their local knowledge and limited means. While these strategies may not be optimal they obviously constitute the basis for potentially effective improved technologies which can be developed and communicated through an efficient extension system, hence the need to precisely identify them and understand the factors that affect their choice. The main objective of this study was therefore, to identify the adaptation strategies and investigate the factors influencing smallholder farmers’ choice of those adaptation strategies. The study made use of multi-stage stratified sampling technique to select 160 respondents across four agro-ecological zones (lowlands, highlands, foothills and Senqu River Valley) in Leribe and Mohales’Hoek districts of Lesotho. Primary data for the study were collected using semi - structured questionnaire assisted with interview schedules administered on the respondents. Data collected were analysed using descriptive statistics and the multinomial logistics regression model. The results show that there are more males than females, majority of the respondents’ attained primary education, and older people dominate the smallholder farming system. The adaptation strategies used in MNL model were soil and water management, crop management and livestock management. The results further revealed that soil and water management strategies were the most adopted climate change strategies amongst smallholder farmers. It is understood that marital status, age and gender, income, land tenure, crop grown, extension services, and agro-ecological zones are the determinant factors influencing the choice of the adaptation strategies. This study concludes by recommending that smallholder farmers should be sensitised about climate change and both government and non-government organisations working on climate change related issues should direct their attention to rural communities to ensure effective response to climate change.
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- Date Issued: 2017
Physiochemical, fatty acids, lipid oxidation, sensory characteristics and consumer acceptance of warthog cabanossi produced with pork backfat and fat-tailed sheep backfat
- Authors: Mahachi, Leo Nyikadzino
- Date: 2017
- Subjects: Fatty acids Lipids -- Oxidation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6259 , vital:29530
- Description: The objective of this study was to determine the effect of different fat inclusion levels and fat types on the physical and chemical attributes, lipid oxidation, fatty acid composition and sensory characteristics of warthog cabanossi. To achieve this, three types of cabanossi with different pork backfat levels (10 percent, 20 percent and 30 percent) were produced for the first experiment. The results from the study showed that different inclusion levels of pork backfat had an influence (P ≤ 0.05) on the physicochemical and fatty acid composition of warthog cabanossi but did not influence lipid oxidation (P > 0.05). The highest (P ≤0.05) pH, weight and moisture decline was observed in the 10 percent pork backfat cabanossi compared to the 20 percent and 30 percent treatments. However, no differences (P > 0.05) in the water activity of the product were observed. As expected total fat was lower in the 10 percent fat treatment and increased concomitantly. Similarly, protein, ash and salt were higher in the 10 percent fat cabanossi and decreased concomitantly. Differences in the fatty acid composition were observed between treatments. Furthermore, backfat level affected the sensory attributes and consumer acceptance of the cabanossi. Ten percent backfat cabanossi was scored higher (P ≤0.05) for most sensory attributes. Consequently, it was observed that the consumer panel preferred and scored the 10 percent fat cabanossi higher with regards to appearance and taste. In the second experiment, two cabanossi treatments of different fat types (pork backfat and fat-tailed sheep backfat) were produced. The weight loss, moisture content, pH, water activity and salt content did not differ (P > 0.05) between the two cabanossi products. However, there were differences (P ≤0.05) in the protein, fat and ash contents; where protein and ash were higher in the pork backfat cabanossi whilst fat was higher in the sheep backfat cabanossi. Thiobarbituric reactive substances (TBARS) were similar (P > 0.05) between the two fat types cabanossi which could be explained by similar fatty acid profiles being reported for the two cabanossi although the n-6:n-3 ratio was higher (P ≤0.05) in sheep backfat cabanossi. Results from the descriptive sensory analysis showed two distinct products (P ≤0.01) where pork backfat cabanossi scored higher for most attributes. However, the lower scores for sheep backfat cabanossi were within an acceptable range. Sheep backfat cabanossi were also scored for unique attributes that were not detected in the pork backfat cabanossi. This study concluded that fat-tailed sheep backfat can be used to produce an unique cabanossi product of acceptable quality.
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- Date Issued: 2017
Agricultural-based commodity chains and development: the case of the tobacco sector in Zimbabwe
- Authors: Thring, Stephen Richard
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/5337 , vital:20814
- Description: This thesis examines the nature of governance in the Zimbabwean tobacco value chain and what upgrading implications this has for participants at the lower end of the value chain, with a particular focus on smallholder tobacco growers. The nature of governance and upgrading opportunities will provide further implications for broader economic development in Zimbabwe. Value chain analysis was the over-arching method, adopting a mixed methods approach of both quantitative and qualitative data analysis. Data attained from the Tobacco and Industry Marketing Board (TIMB) was used to construct a Zimbabwean tobacco profile. This information was used to construct a simple Global Value Chain (GVC) framework in order to obtain an understanding of the Zimbabwean tobacco value chain. Information was gathered at the top end of the value chain via documents and data from British American Tobacco (BAT) and information was gathered at the middle and lower end of the value chain through interviews. It was found that the Zimbabwean tobacco value chain is characterised by two types of governance: modular and hierarchy. Modular governance existed where the value chain was disjointed by the leaf merchant and hierarchy governance existed where cigarette manufacturers have vertically integrated themselves backwards into the tobacco growing segment. It was found that contract lines offer smallholder tobacco growers’ financial and technical support that would otherwise be difficult to attain. This increased the likelihood for smallholder tobacco growers to produce a high quality crop that met Good Agricultural Practices (GAP) and other compliancy requirements; therefore achieving product and process upgrading. However, the environmental impact of tobacco growing through deforestation and the possibility of lead cigarette manufacturers relocating their operations to a different geographical location (as is the nature of GVCs) threatens the sustainability of Zimbabwe’s tobacco industry. Despite these issues it was argued that the tobacco value chain could assist Zimbabwe’s economy in diversifying away from simple tobacco production towards valueadding tobacco sectors, such as processing, by-product processing and cigarette manufacturing.
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- Date Issued: 2017