1,720,956 research outputs found
In vitro conservation of selected endangered plant species indigenous to the Cape Floristic Region, South Africa
No full textThesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2016.This study focused on optimising four types of in-vitro conservation methods, namely: 1), micropropagation, 2) in-vitro slow growth, 3) seed germination and 4) cryopreservation for selected endangered plant species indigenous to the Cape Floristic Region. It is one of the targets set by United Nations millennium development goals, to integrate different conservation measures in order to preserve plant diversity and mitigate losses of genetic diversity. Therefore this study uses Phalaenopsis hybrids as a trial species that can be studied for the conservation of endangered Disa and Eulophia species through micropropagation and in vitro slow growth. Also conservation attempts on Leucadendron and Mimetes species that occur in the Cape Floristic Region were attemted to increase population densities by increasing germination percentages using smoke. Furthermore, the study attempted to store seeds by assessing different cooling rates for optimising cryopreservation measures for effective conservation. The use of tissue culture to increase propagules especially critically endangered species in South African has proven to be feasible. For the trial hybrids, shoot and protocorm explants of Phalaenopsis Psychosis Pink X P. No. 1; P. Large white X P. Large pink; P. No. 1 X P. Large pink; P. Mini pink X Brighton belle; and the P. aphrodite formed clusters of protocorms and shoots when cultured on ½ strength MS media supplemented with 10, 20 and 30gL-1 banana extract or ½ strength Murashige and Skoog, (1962) (MS) media supplemented with peptone. Continuous protocorms formation could therefore be obtained by culturing endangered Disa and Eulophia shoots and protocorms on banana containing media. Plantlet conversion from somatic embryos produced on 10gL-1 banana extract enriched media was successfully achieved on ½ strength MS supplemented with 20gL-1 sucrose and no plant growth regulators in the medium. However, optimum rooting was achieved on ½ strength MS supplemented with 30gL-1 of banana extract and this medium yielded the highest survival percentages for plantlet acclimatisation. Furthermore, ½ strength MS supplemented with 1gL-1 of peptone served as a stimulant for shoot development and protocorm formation. When coupled with banana extract at all stages of development, regeneration and rooting were enhanced
The use of traditional weather forecasting by agro-pastoralists of different social groups in Bobirwa sub-district, Botswana
Get PDFAgro-pastoralists of Bobirwa sub-district depend mainly on rain-fed agriculture as a source of their livelihood. However, this agro-pastoralism is affected by climatic variability. Advanced warning of upcoming weather information is, therefore, important in informing farming decisions. Traditional weather forecasting is often a major planning tool used to inform agro-pastoralists’ decision making and has been handed from one generation to another. For instance, local knowledge indicators are used to determine onset of rainfall and quality of the rainfall expected. However, there are numerous factors that may have affected the effective use of and dependence on traditional weather forecasting over the years. For this reason, it is critical to examine the current state and use of traditional weather forecasting among the agro-pastoralists. This thesis describes the traditional weather forecasting that agro-pastoralists in Bobirwa sub-district Botswana hold and use in planning for agricultural activities to cope with climate variability. It also examines changes that have been observed in the use of traditional weather forecasting over time. By exploring the knowledge used to generate early warning systems and coping strategies to climate variability of agro-pastoralists, we examine underlying vulnerabilities and resilience possibilities. Data was collected through purposively selecting a total of 101 agro-pastoralists who were further stratified by age and gender. The following qualitative techniques were used in data collection: semi-structured interviews (54 interviewees constituting 37 forecasters and 17 non-forecasters), focus group discussions (47 participants consisting of between 4 and 12 participants), and key informant interviews (11 forecasters who use multiple indicators). The snowballing technique was the main sampling strategy. Knowledgeable traditional forecasters in FGD’s were used to identify key informants with whom semi-structured interviews were conducted. All data was analysed using the thematic analysis method. Data was constructed using a cyclical process to generate themes which consisted of the initialisation (capturing participants’ accounts), construction of themes, relating the themes and developing results. From the study, it was found that male and female elderly agro-pastoralists in Bobirwa are more knowledgeable about traditional weather forecasting and use the traditional weather forecasting techniques to inform their decisions, while the less-knowledgeable adults and youth expressed having limited use of traditional weather forecasting in decision making. There were also differences in the use of specific traditional indicators based on the positionality of an individual in the society as well as age and gender. While the participants indicated that traditional weather forecasting is a reliable technique, climate change is believed to have resulted in unpredictable trends in recent years. For example, excessive floods, patchy and reduced rainfall, extensive heat spells with no specific patterns, changes in biological indicators, and thus, present a challenge to these agro-pastoralists. In all, traditional weather forecasting remains a cultural artefact in the community and will always be practised by the agro-pastoralists. However, many elements threaten the existence of the traditional weather forecasting such as the death of custodians of knowledge, the disruptive nature of climate change, youth migration to cities and the ubiquity of modern practices. Further to this, the prevalence of modern practices, for example Christianity, is transforming the use and beliefs of individuals in traditional weather forecasting leading to reduced intergenerational transfers of the traditional weather forecasting. It is prudent to expect that as cultural practices change within societies, cognisant of the fact that culture is dynamic, it is also expected that the use of traditional weather forecasting will change. It should, however, not be construed that the changes in the use of traditional weather and seasonal forecasting are an indication of the unreliability of traditional indicators, but inability of individuals to forecast. In turn, the study recommends the conservation of the traditional weather forecasting and traditionally important biological indicators. This can be promoted through documentation and teaching of traditional weather and seasonal forecasting techniques in conventional educational programmes. Alongside this, integration of traditional and scientific weather forecasting could be used to develop national policies to facilitate effective drought and flood coping strategies that are inclusive and aimed at limiting the traditional weather forecasting knowledge gap among agro-pastoralists of different age and gender groups. Interventions by the government can be redirected to traditional leaders or elders who bear extensive knowledge on traditional weather indicators to create awareness and facilitate knowledge exchange especially in aiding agro-pastoralists to cope with climate variability. Also, for those who are sceptical of traditional weather forecasting, the use of religious gatherings of different denominations can be an option to facilitate awareness raising of coping strategies that can be explored to reduce vulnerability amongst this group of agro-pastoralists by teaching them to adapt to the changing weather using local knowledge
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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