138 research outputs found

    Factors influencing access and usage of e-Resources at Nkumba University Uganda

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    Abstract: Electronic resources (e-Resources) are now generally perceived as powerful sources of information and are regarded as indispensable scholarly reference source. With easy access, e-Resources provide synthesized information sources with regularly updated information and hyperlinks to offsite contents providing latest information and thinking on a subject. Aiming to explore access and usage of e- Resources at Nkumba University Library (NUL), this study investigated the level of accessibility and usage of subscribed e-Resources by third year undergraduate students. Understanding the level of access and usage of e-Resource is important because it gives pointers to the level of access of contemporary knowledge in the learning and research processes by the students. A positivist approach hinged on the modified Unified Theory of Acceptance and Use of Technology (UTAUT) formed the theoretical basis of the study. Data was collected using a self-administered questionnaire, interviews and observations. A 51% of encompassing 110 individuals out of 216 responded to the questionnaire. This research provides evidence and pointers that need to be considered when designing interventions to encourage usage and access of e-Resources in contextually similar environments. The study proposes a conceptual framework that depicts factors cardinal in influencing access and usage of e-Resources more especially in resourceconstrained countries

    Quality by Design Optimization of Cold Sonochemical Synthesis of Zidovudine-Lamivudine Nanosuspensions:

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    Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used to manage HIV/AIDS infection. The compounds require frequent dosing, exhibit unpredictable bioavailability and a side effect profile that includes hepato- and haema-toxicity. A novel pseudo one-solvent bottom-up approach and Design of Experiments using sodium dodecyl sulphate (SDS) and α-tocopheryl polyethylene glycol succinate 1000 (TPGS 1000) to electrosterically stablize the nano co-crystals was used to develop, produce and optimize 3TC and AZT nano co-crystals. Equimolar solutions of 3TC in surfactant dissolved in de-ionised water and AZT in methanol were rapidly injected into a vessel and sonicated at 4 °C

    Assessing Stream-Aquifer Connectivity in a Coastal California Watershed

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    We report the results of field and laboratory investigations of stream-aquifer interactions in a watershed along the California coast to assess the impact of groundwater pumping for irrigation on stream flows. The methods used include subsurface sediment sampling using direct-push drilling, laboratory permeability and particle size analyses of sediment, piezometer installation and instrumentation, stream discharge and stage monitoring, pumping tests for aquifer characterization, resistivity surveys, and long-term passive monitoring of stream stage and groundwater levels. Spectral analysis of long-term water level data was used to assess correlation between stream and groundwater level time series data. The investigations revealed the presence of a thin low permeability silt-clay aquitard unit between the main aquifer and the stream. This suggested a three layer conceptual model of the subsurface comprising unconfined and confined aquifers separated by an aquitard layer. This was broadly confirmed by resistivity surveys and pumping tests, the latter of which indicated the occurrence of leakage across the aquitard. The aquitard was determined to be 2–3 orders of magnitude less permeable than the aquifer, which is indicative of weak stream-aquifer connectivity and was confirmed by spectral analysis of stream-aquifer water level time series. The results illustrate the importance of site-specific investigations and suggest that even in systems where the stream is not in direct hydraulic contact with the producing aquifer, long-term stream depletion can occur due to leakage across low permeability units. This has implications for management of stream flows, groundwater abstraction, and water resources management during prolonged periods of drought

    Multidisciplinarity in Data Science Curricula

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    This paper sought to identify and compare disciplinary emphases in data science curricula across South Africa’s 26 public universities using a website scoping review method. The key findings reveal that only 12 of the 26 universities offer data science programmes that are publicly accessible on their websites. Of those 12, only 5 offer data science at the undergraduate level, and these undergraduate programmes are objectified (entirely leaning) to the science, technology, engineering, and mathematics (STEM) disciplines. Only seven of the universities offer a few non-STEM subjects with only one offering more non-STEM subjects compared to STEM subjects. The implications are that curricula of data science, which is multidisciplinary in nature, are more likely to inherit the STEM curricula challenges. The resultant impact will therefore likely extend to skills, future careers, and employment, in view of the growing demand for data scientists amid the unemployment challenges. It is recommended that intentional efforts must be made to necessarily ideologise non-STEM disciplines into data science curricula in South Africa, that is, to deeply embed societal contexts into data science curricula

    Tomography of the Darcy velocity from self-potential measurements

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    An algorithm is developed to interpret self-potential (SP) data in terms of distribution of Darcy velocity of the ground water. The model is based on the proportionality existing between the streaming current density and the Darcy velocity. Because the inverse problem of current density determination from SP data is underdetermined, we use Tikhonov regularization with a smoothness constraint based on the differential Laplacian operator and a prior model. The regularization parameter is determined by the L-shape method. The distribution of the Darcy velocity depends on the localization and number of non-polarizing electrodes and information relative to the distribution of the electrical resistivity of the ground. A priori hydraulic information can be introduced in the inverse problem. This approach is tested on two synthetic cases and on real SP data resulting from infiltration of water from a ditch

    A comparative study of the effect of different stabilizers on the critical quality attributes of self-assembling nano co-crystals

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    Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used orally to manage HIV/AIDS infection. A pseudo one-solvent bottom-up approach was used to develop and produce nano co-crystals of 3TC and AZT. Equimolar amounts of 3TC dissolved in de-ionized water and AZT in methanol were rapidly injected into a pre-cooled vessel and sonicated at 4 °C. The resultant suspensions were characterized using a Zetasizer. The particle size, polydispersity index and Zeta potential were elucidated. Further characterization was undertaken using powder X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and energy dispersive X-ray spectroscopy scanning electron microscopy. Different surfactants were assessed for their ability to stabilize the nano co-crystals and for their ability to produce nano co-crystals with specific and desirable critical quality attributes (CQA) including particle size (PS) less than 1000 nm, polydispersity index (PDI) less than 0.500 and Zeta potential (ZP) less than −30 mV. All surfactants produced co-crystals in the nanometer range. The PDI and PS are concentration-dependent for all nano co-crystals manufactured while only ZP was within specification when sodium dodecyl sulfate was used in the process

    Top-Down Synthesis of a Lamivudine-Zidovudine Nano Co-Crystal

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    Lamivudine (3TC) and zidovudine (AZT) are antiretroviral agents used to manage HIV/AIDS infection. A wet media milling top-down approach was used to develop and produce nano co-crystals of 3TC and AZT. Micro co-crystals were prepared by solvent evaporation and subsequently milled in the presence of two surfactants, viz., sodium lauryl sulfate (SLS) and α-tocopheryl polyethylene glycol succinate 1000 (TPGS 1000). Optimisation was undertaken using design of experiments (DoE) and response surface methodology (RSM) to establish and identify parameters that may affect the manufacturing of nano co-crystals. The impact of SLS and TPGS 1000 concentration, milling time, and number of units of milling medium on the manufacturing of nano co-crystals, was investigated. The critical quality attributes (CQA) monitored were particle size (PS), Zeta potential (ZP), and polydispersity index (PDI). Powder X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry, transmission electron microscopy, energy dispersive X-ray spectroscopy scanning electron microscopy, and cytotoxicity assays were used for additional characterization of the optimised nano co-crystal. The mean PS, PDI, and ZP of the optimised top-down nanocrystal were 271.0 ± 92.0 nm, 0.467 ± 0.073, and −41.9 ± 3.94 mV, respectively. In conclusion, a simple, inexpensive, rapid, and precise method of nano co-crystal manufacturing was developed, validated, and optimised using DoE and RSM, and the final product exhibited the target CQA

    Information knowledge and technology for Development in Africa

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    Information, knowledge, and technology occupy significant space in the information and knowledge society and ongoing debates on development such as sustainable development goals (SDGs) agenda 2030 and the fourth industrial revolution (4IR). Disruptive technologies and cyber-physical systems, obscuring the lines between the physical, digital and biological, escalated by the COVID-19 pandemic, present a ‘new normal’ that profoundly affects the nature and magnitude of responses required to sustain and benefit from the new developments. Africa, known for late adoption of new technologies and innovations, is leapfrogging development stages in several enviable ways. This book, Information knowledge and technology for development in Africa’, written by eminent African scholars, comprises chapters that satisfactorily address information access, artificial intelligence, information ethics, e-learning, library and information science education (LISE) in the 4IR, data literacy and e-scholarship, and knowledge management, which are increasingly essential for information access, services, and LISE in Africa. We expect the book to support research, teaching and learning in African higher education and worldwide for comparative scholarship

    Cash or Food? Which Works Better to Improve Nutrition Status and Treatment Adherence for HIV Patients Starting Antiretroviral Therapy

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    The overall objective of this DFID-funded study was to understand whether cash or food transfers were more effective for HIV-positive individuals starting antiretroviral therapy (ART) in improving nutrition, health status and adherence to ART. HIV-positive individuals initiating ART at the St Francis Mission Hospital in Katete District, Eastern Province, were randomly allocated to two treatment groups (cash and food), and given a food basket or its cash equivalent monthly, for eight months. Both treatment groups saw significant increases (p-value <0.001) in Body Mass Index (BMI), Household Dietary Diversity Score, good adherence to ART, and in mean CD4 count, but there were no significant differences between the two treatment groups in these measures. The study concluded that the provision of cash or food for eight months when clients start ART confers similar and significantly positive effects in improving clients’ nutrition and health. Providing cash is likely to be more cost-effective
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