90 research outputs found
Strategies for managing scholarly content at universities in Kenya.
Ph. D. University of KwaZulu-Natal, Pietermaritzburg 2015.This study investigated strategies employed by universities in Kenya in managing scholarly content and addressed the following research questions: What kinds of scholarly content are generated and used in universities in Kenya? How is the scholarly content generated and/or acquired in universities in Kenya preserved and archived for current and future use? How do Kenyan scholars communicate amongst themselves in the various stages of their research work? To what extent do Kenyan scholars participate in local and/or international professional social networks? To what extent do existing institutional facilities in the universities support scholarsā research and communication needs? The study was underpinned by three theoretical lenses namely: The Conversation Theory, the Social Network Theory and the Knowledge Management Process Model. The Knowledge Management Process Model was the main theoretical lens used to underpin the research problem in this study as it encompassed most issues of the research problem on the subject matter of scholarly content management in universities in Kenya.
The study was based on the post-positivist paradigm and applied quantitative and qualitative approaches. A survey plan was employed within a multiple case study design. The population of the study consisted of academic staff and postgraduate students drawn from six purposively selected universities using the 2013 Webometric academic ranking of best Universities in Kenya (based on the qualitative and quantitative aspects of research output). Convenience sampling was used to identify participants for the study from academic staff and postgraduate students. In this strategy, those respondents who were available and willing to participate in the study when the questionnaires were being administered were included in the study. Academic staff and postgraduate students were targeted for the study since they were considered key actors in the scholarly communication process as creators and consumers of scholarly content. Purposive sampling was used to target all the six University Librarians and all six representatives of the universitiesā research units respectively. Therefore a census of the University Librarians and Representatives of the universitiesā research units was taken. These respondents were considered key informants since they were directly involved in facilitating and managing research and scholarly communication at the universities. Self-administered questionnaires were used to collect data from 350 academic staff and 370 postgraduate students while interviews were used to collect data from the key informants from the research units and also from the university librarians. Qualitative data were analysed and presented using derived themes while quantitative data were analysed using IBM SPSS Statistics and Gephi Social Network Analysis software. Descriptive and inferential statistics were generated by the statistical software while the social network analysis software was used to depict the social networks existing among scholars at the universities. Results of quantitative data analysis were presented using tables, graphs and charts. Cronbachās Alpha was generated for individual questions in the survey questionnaire to help determine internal validity. The study adhered to the ethical protocol of the University of KwaZulu-Natal. Moreover, permission was obtained from the National Council of Science and Technology in Kenya as well as from individual universities to allow the study to be undertaken in the selected universities.
The results revealed that several types of scholarly content were generated through research and publications in the universities surveyed, with the most common being theses, journal articles and conference papers. The results further revealed that a majority of academic staff in universities in Kenya were not actively involved in knowledge generation through research and publications with only 42% of academic staff and 37% of postgraduate students producing 1-3 journal articles in the period 2010-2014. The results also showed that there was high level of awareness among academic staff and postgraduate students regarding preservation of scholarly content as most respondents documented their research procedures, backed up information, moved files to newer computers and used printouts to preserve content. However, the respondents seemed to hardly use digital archives or university servers for preservation of their scholarly content. The results seemed to suggest heavy reliance on modern technology-enabled communication techniques and face-to-face interactions for communication amongst scholars. Institutional repositories were hardly used for scholarly communication although they existed in all universities surveyed. Social Network Analysis revealed limited participation by respondents in local and international scholarly networks with majority of collaborations taking place as independent dyads or triads. Results also revealed inadequate institutional support for research and scholarly communication including funding, material and physical infrastructure, mentorship, and ICT facilities.
From the results, it is concluded that strategies for managing scholarly content at universities in Kenya are weak, impacting negatively on quality, quantity and visibility of scholarly content. It is therefore concluded that a policy framework that would encompass the different facets of managing scholarly content is necessary. Specifically, research productivity in universities in Kenya was low owing to among other factors poor research culture, poor mentorship, weak social ties between scholars, and inadequate support for research and scholarly communication in the universities. Moreover, visibility of scholarly content was found to be poor owing to reliance by academic staff and postgraduate students on traditional publishing modes such as subject journals and conference proceedings compared to institutional websites and repositories. The study recommended among other things development of specific strategies to enhance management of scholarly content within the universities. The study recommends development of an elaborate policy framework to guide content generation, storage, dissemination, access and use of scholarly content in universities in Kenya. Additionally, the study recommended institutionalization of mentorship programs to entrench scholarship amongst academic staff and graduate students; nurturing of scholarly collaboration to facilitate knowledge sharing and enhance the quality, quantity and visibility of research output from the universities; provision of more research funds especially by government to strengthen research capacity of the universities; and strengthening of university research niches to improve quality of research. The study makes an original contribution to the area of managing scholarly content from the perspective of universities in Kenya. Unlike previous studies that focus primarily on management of scholarly content from academic staff, the present study included academic staff, postgraduate students and librarians. The Social Network Analysis model was used to depict the departmental, interdepartmental and international scholarly collaborations in the universities surveyed Suggestions for further research include research to establish the nature of policies required at institutional and government level to improve research capacity and training programs in universities in Kenya. It is evident that absence of such policies is negatively impacting on the quality of research going on in universities in Kenya, despite the large quantity of resources already invested on research. Therefore, without such policies, it is inevitable that quality of research within universities in Kenya will continue to be low. Further research is also necessary to evaluate the actual use of electronic resources in university libraries. The study results revealed low usage of these resources by scholars with some claiming they were inaccessible. Such a study would establish usage levels as well as reasons for use or non-use of the resources. A further suggestion is for analysis of the scholarly collaborations existing among Kenyan scholars by using bibliometric techniques and social network analysis to determine the level of research collaboration among scholars. This will provide a further understanding of the nature of their collaborations, as well as research productivity and visibility of these scholars in the global literature
Theoretical study of magnetic ordering of defects in diamond
Magnetic ordering of dopants in diamond holds the prospect of exploiting diamondās unique
properties in the emerging field of spintronics. Several transition metal defects have been
reported to order ferromagnetically in various semiconductors, however, low Curie
temperatures and lack of other fundamental material properties have hindered practical
implementation in room temperature spintronic applications. In this Thesis, we consider the
energetic stability of 3d transition metal doped-diamond and its magnetic ordering properties
at various lattice sites and charge states using ab initio Density Functional Theory methods.
We find the majority of 3d transition metal impurities in diamond at any charge state to be
energetically most stable at the divacancy site compared to substitutional or interstitial lattice
sites, with the interstitial site being highly unstable (by ~8 - 10 eV compared to the divacancy
site). At each lattice site and charge state, we find the formation energies of transition metals
in the middle of the 3d series (Cr, Mn, Fe, Co, Ni) to be considerably lower compared to
those early or late in the series. The energetic stability of transition metal impurities across
the 3d series is shown to be strongly dependent on the position of the Fermi level in the
diamond band gap, with the formation energies at any lattice site being lower in p-type or ntype
diamond compared to intrinsic diamond.
Further, we show that incorporation of isolated transition metal impurities into diamond
introduces spin polarised impurity bands into the diamond band gap, while maintaining its
semiconducting nature, with band gaps in both the spin-up and spin-down channels. These
impurity bands are shown to originate mainly from s, p-d hybridization between carbon sp
3
orbitals with the 3d orbitals of the transition metal. In addition, the 4p orbitals contribute
significantly to hybridization for transition metal atoms at the substitutional site, but not at
the divacancy site. In both cases, the spin polarisation and magnetic stabilization energies are
critically dependent on the lattice site and charge state of the transition metal impurity.
By allowing magnetic interactions between transition metal atoms, we find that ferromagnetic
ordering is likely to be achieved in divacancy Cr+2, Mn+2, Mn+1 and Co0 as well as in
substitutional Fe+2 and Fe+1, indicating that transition metal-doped diamond is likely to form
a diluted magnetic semiconductor which may successfully be considered for room
temperature spintronic applications. In addition, these charge states correspond to p-type
diamond, except for divacancy Co0, suggesting that co-doping with shallow acceptors such as
B (
will result in an increase of charge concentration, which is likely to
enhance mediation of ferromagnetic spin coupling. The highest magnetic stabilization energy
occurs in substitutional Fe+1 (33.3 meV), which, also exhibits half metallic ferromagnetic
ordering at the Fermi level, with an induced magnetic moment of 1.0 Ī¼B per ion, thus
suggesting that 100 % spin polarisation may be achieved in Fe-doped diamond.PhysicsD. Phil. (Physics
Extraction and analysis of tea (Camellia sinensis) seed oil from different clones in Kenya
Kenyan tea (Camellia sinensis) is widely grown for its leaves and is commercialized as black tea. Product diversification and value addition is currently an area of great interest. This study provides data on the physico-chemical properties of Kenyan tea seed oil from selected clones of tea seeds to ascertain its potential applications. Soxhlet extraction using hexane was employed to obtain tea seed oil followed by chemical analysis to assess its properties. Oil yield, iodine value, saponification value, peroxide value, free fatty acids, total polyphenols and antioxidant activity were determined. The oil yields ranged between 16 to 25% w/w. Iodine value was in the range of 86 to 91 g I2/100 g, peroxide value < 3.5 meq O2/kg, saponification value between 182 to 187 mg KOH/g, free fatty acid < 1.5% oleic acid, total polyphenols 0.036 to 0.043 mg/L gallic acid and antioxidant activity of between 14 to 21% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. Tea seed oil is stable and can be a potential source of natural antioxidants.Keywords: Tea seed oil, iodine value, saponification value, peroxide value, free fatty acids, total polyphenols, antioxidant activityAfrican Journal of Biotechnology Vol. 12(8), pp. 841-84
The linkage between settlement profile and choice of sanitation system in peri-urban areas: a case study of Nakuru municipality
Presently human settlements in developing societies do not effectively address problems in urban areas
including inadequate housing, unreliable energy sources, inadequate water supply, poor sanitation
systems and lack of access roads in informal settlements. Recently, Nakuru town water supply has been
characterized by chronic shortages and this threatens sanitation in residential and industrial functions
within the Municipality. āFlying toiletsā and pit latrines are conspicuous in low income high density
settlements, while flush toilets, sewer systems and septic tanks are common among middle and high
income low density settlements. A study was carried out to assess and map linkages between sanitation
technologies and settlements profile in the municipality and examine implications of resource-oriented
sanitation technologies. Results showed that sanitation situation in low income settlements and choice of
sanitation technology is limited to multi-factors. 70% of respondents indicated a strain economically as a
determining factor in the choice of sanitation technology. The research recommended the adoption of
ecological sanitation as a paradigm shift from conventional sanitation
Polybrominated Diphenyl Ethers Pollution in Urban and Rural Settingsā Ambient Air in Kenya: An Insight into Concentration Levels, Compositional Profile and Seasonal Variation
Air samples were collected from three urban and one rural sites in Kenya with the aim of establishing pollution levels of Polybrominated Diphenyl Ethers. Forty-eight air Samples were collected by passive air sampling, Soxhlet extracted and analysed for brominated diphenyl ethers using gas chromatography coupled with mass spectrometer. The mean concentration of polybrominated diphenyl ethers residue in air ranged from ā¤0.9 to 152.72Ā±3.19 pgmā3. The predominant congener was 2,2ā²,4,4ā²-tetra-bromodiphenyl ether with mean concentration range of 1.94Ā±0.03 to 152.72Ā±3.19 pgmā3 followed by 2,2ā²,4,4ā²,5-penta- bromodiphenyl ether with mean concentration range of 1.32Ā±0.06 to 66.83Ā±1.19 pgmā3. Seasonal variations of the pollutants showed a high level of Polybrominated Diphenyl Ethers in hot dry season in range of 1.94Ā±0.03 to 152.72Ā±3.19 pgmā3. Air samples from Dandora and Industrial area both from urban location recorded high concentrations of the analysed polybrominated diphenyl ethers compared with the air samples from the rural location
SOME FACTORS INFLUENCING THE FREE FLUORIDE CONTENT IN BLACK TEA INFUSIONS
Fluoride is an essential micro-nutrient owing to its role in the
prevention of dental caries. Chronic exposure to high levels of the ion
(F-) results in both dental and skeletal fluorosis. A study was carried
out to determine free fluoride content in tea ( Camellia sinensis )
infusions of different grades of black Cut, Tear and Curl (CTC) tea.
Tea infusions, 1% w/v of 112 teas of different grades and origins, were
prepared using boiling distilled water and their free fluoride contents
quantified using a Fluoride Ion Selective Electrode (FISE) method. The
free fluoride content of the teas was 0.37\ub10.04 \ub5g F- ml-1.
Infusions of tea grades BP1 and BMF gave the highest (0.40\ub10.22
\ub5g F- ml-1) and lowest (0.32\ub10.10 \ub5g F- ml-1) free
fluoride contents, respectively. There being no national and
international Maxima Residue Limit (MRL) for fluoride in tea, all the
teas analysed may be regarded to be safe for consumption with regard to
their free fluoride contents based on the 1.5 \ub5g F- ml-1, World
Health Organisation\u2019s (WHO) guideline for fluoride in drinking
water. Further, the effects of tea grades and area of production, on
the fluoride content in tea infusions were significant (P<0.05),
hence the need to enact safety guidelines and monitor continuously the
fluoride levels for all types of tea products to prevent excessive
intake.Le Fluor est un micro-\ue9l\ue9ment essentiel lorsque consomm\ue9
en dessous de certains seuils eu \ue9gard \ue0 son r\uf4le dans
la pr\ue9vention des caries dentaires. Par ailleurs,
lorsqu\u2019utilis\ue9 en exc\ue8s, les ions (F-) entrainent une
fluorose des dents et du squelette . Une \ue9tude \ue9tait
men\ue9e pour d\ue9terminer la concentration en fluor libre des
infusions de th\ue9 ( Camellia sinensis ) de diff\ue9rentes
classes de the noir de la cat\ue9gorie CTC. Les infusions de
th\ue9, 1% p/v de 112 th\ue9s de diff\ue9rentes classes et
origines \ue9taient pr\ue9par\ue9es en utilisant une eau
bouillante distill\ue9e et leurs concentrations en fluor libre
quantifi\ue9es par la m\ue9thode dite de Fluoride Ion Selective
Electrode (FISE). La concentration en fluor libre dans les th\ue9s
\ue9tait de 0.37\ub10.04 \ub5g F-ml-1. Les classes de th\ue9
BP1 et BMF ont pr\ue9sent\ue9 respectivement des concentrations les
plus \ue9lev\ue9es de (0.40\ub10.22 \ub5g F-ml-1) et moins
elev\ue9es de (0.32\ub10.10 \ub5g F-ml-1) du fluor libre. Etant
donn\ue9 que sur le plan national et international il n\u2019ya pas
de Limite Maximale de R\ue9sidus (MRL) pour le fluor dans le
th\ue9, tous les \ue9chantillons des th\ue9s analys\ue9s
pourraient \ueatre consid\ue9r\ue9s comme appropri\ue9s \ue0
la consommation eu \ue9gard \ue0 leur concentrations en fluor libre
sur base de 1.5 \ub5g F-ml-1 tel que recommand\ue9 par
l\u2019Organisation Mondiale de la Sant\ue9 (OMS) pour l\u2019eau
potable. En plus, les effets des classes du th\ue9 et les
r\ue9gions productrices sur la concentration du fluor dans les
infusions de th\ue9 \ue9taient significatives (P<0.05),
d\u2019o\uf9 la n\ue9c\ue9ssit\ue9 de mettre sur pied des
mesures de protection et faire le suivi r\ue9gulier des niveaux du
fluor pour tous les types de produits de th\ue9 afin
d\u2019\ue9viter une consommation excessive du fluor
Computational Study of A15 Ru-Based Alloys for High-Temperature Structural Applications
The structural, magnetic, electronic and elastic properties of A15 X3Ru (XĀ =Ā Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) binary alloys are investigated using first-principles density functional theory (DFT) methods. Ru-based alloys have attracted remarkable research interest due to their unique properties, which make them suitable for high-temperature structural applications. In this chapter, the properties of several A15 Ru-based alloys are investigated in order to select the best suitable alloy/s for aerospace application. Heats of formation are calculated to determine the thermodynamic stability of the materials. Knowledge of the values of elastic constants is essential for understanding the mechanical properties of the materials. From our calculated elastic constants, the bulk modulus, shear modulus, Youngās modulus, Poissonās ratio, melting temperature, anisotropic factor and the ratio B/G are determined. The electronic density of states are calculated and discussed. Lastly, the magnetic properties of A15 X3Ru alloys are studied. Thermodynamically stable Mn3Ru possesses high-magnetic moment compared to other X3Ru alloys, these results could pave way to experimental realization (synthesis) of Mn3Ru material
Occurrence and Distribution of Polybrominated Diphenyl Ethers in Water from Nairobi River Basin, Kenya, East Africa
Polybrominated diphenyl ethers are linked to adverse health effects that includethyroid hormone disruption, neuro-developmental deficit, abnormal pregnancy,and potential carcinogens. This study was aimed at assessing the concentrationsof selected Polybrominated diphenyl ether compounds in water of Nairobi River.Water samples were collected by grab method from nine sites along the river andanalysed for brominated diphenyl ethers using gas chromatography coupled withmass spectrometer. The mean concentration of polybrominated diphenyl ethersresidue in water ranged from <0.0009 to 72.89 Ā± 6.15 ng/L. The dominantcongeners were 2,2ā²,4,4ā²-tetra- bromodiphenyl ether, 2,2ā²,4,4ā²,5,5ā²-hexabromodiphenylether, 2,2ā²,4,4ā²,6-penta-bromodiphenyl ether, 2,2ā²,4,4ā²,5,5ā²-hexabromodiphenylether and 2,2ā²,4,4ā²,5,6ā²-hexa-bromodiphenyl. The highest meanconcentration of 2,2ā²,4,4ā²-tetra- bromodiphenyl ether was 72.89 Ā± 6.15 ng/L,2,2ā²,3,4,4ā²-penta- bromodiphenyl ether was 14.08Ā±0.68 ng/L, 2,2ā²,4,4ā²,6-pentabromodiphenylether was 43.67Ā±1.47 ng/L, 2,2ā²,4,4ā²,5,5ā²-hexa-bromodiphenylether was 24.78Ā±2.49 ng/L, and 2,2ā²,3,4,4ā²,5ā²,6-hepta-bromodiphenyl ether was11.75Ā±0.97 ng/L. Consequently, as these compounds are known to bioaccumulatein fatty tissues, continued use of the river water poses a health risk toanimals and humans due to contamination across the food chain
Antioxidant activity and effects of Kenyan Tea (Camellia sinensis) on the liver function and serum biochemistry in male Wistar rats
Background: Tea is a beverage that is most widely consumed worldwide. Studies have shown that oral consumption of tea has health benefits however, there is paucity of data in Kenya detailing the biochemical effects of tea in the liver and elucidation of its mechanism of action.Methods: The polyphenol composition and antioxidant capacity of tea were determined by HPLC and the Folins Ciocalteu spectrophotometric methods. Metal levels were determined using flame Atomic Absorption Spectrometer (AAS). Aqueous black and green tea extracts were administered to the rats at dosages of 400mg/kg b.w.t. The effect of tea on total blood proteins, Albumin, ZHX1, TBARS, AST, ALP and ALT were determined by spectrophotometric methods. The body weight of each rat was also determined at one week interval.Results: Total Polyphenols (TP), Total Catechins (TC) and Antioxidant Activity (AA) between the black and green teas were significantly (P0.05) effect on TP, ALB, ALT, AST, ALP, MDA and ZHX1 in the test animals compared with the controls. This data indicates that green tea is rich in catechins while black tea being rich in Theaflavins (TFs) and Thearubigins (TRs). Both tea products possess essential and non-essential metals well within the maximum permissible concentrations.Conclusions: Findings from this study indicate both green and black tea aqueous extracts have polyphenols and high antioxidant activity. Administration of the aqueous tea extracts have no toxicological effect on the liver.
Context-acceptability theories: example of family planning interventions in five African countries.
BACKGROUND: Family planning (FP) can lengthen birth intervals and potentially reduce the risk of foetal death, low birthweight, prematurity, and being small for gestational age. Effective FP is most easily achieved through access to and acceptability of modern contraceptive methods (MCMs). This study aimed to identify mechanisms of acceptability and the contexts in which they are triggered and to generate theories to improve the selection and implementation of effective interventions by studying an intervention integrating FP with childhood immunisation services. METHODS: Qualitative interpretative synthesis of findings from realist evaluations of FP interventions in five African countries was guided by an analytical framework. Empirical mechanisms of acceptability were identified from semi-structured interviews and focus group discussions with key stakeholders (N = 253). The context in which these mechanisms were triggered was also defined. Empirical mechanisms of acceptability were matched to constructs of a theoretical framework of acceptability. Context-acceptability theories (CATs) were developed, which summarised constructs of acceptability triggered for specific actors in specified contexts. Examples of interventions that may be used to trigger acceptability for these actors were described. RESULTS: Seven CATs were developed for contexts with strong beliefs in religious values and with powerful religious leaders, a traditional desire for large families, stigmatisation of MCM use, male partners who are non-accepting of FP, and rumours or experiences of MCM side effects. Acceptability mechanisms included alignment with values and beliefs without requiring compromise, actors' certainty about their ability to avoid harm and make the intervention work, and understanding the intervention and how it works. Additionally, acceptability by one group of actors was found to alter the context, triggering acceptability mechanisms amongst others. CONCLUSIONS: This study demonstrated the value of embedding realist approaches within implementation research. CATs are transferable theories that answer the question: given the context, what construct of acceptability does an intervention need to trigger, or more simply, what intervention do we need to apply here to achieve our outcomes? CATs facilitate transfer of interventions across geographies within defined contexts
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