Faculty of Social Sciences and Technology

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    Application of resource dependency theory and transaction cost theory in analysing outsourcing information communication services decisions: A case of selected public university libraries in Kenya
    (Emerald Group Publishing Limited, 1983) Kiplang’at, Joseph; Gichoya, David; Mwai, Naomi Wangari
    Purpose – The aim of this paper is to establish how resource dependency theory (RDT) and transaction cost theory (TCT) can inform decisions to outsource ICT services by public university libraries in Kenya. Design/methodology/approach – The study adopted a multiple case study strategy in four selected public universities libraries in Kenya. Purposive sampling was used to identify respondents and data collection was done using a semi-structured interview schedule. Findings – The study highlights how RDT and TCT theoretical perspectives illuminate some of the reasons, and problems associated with Information and Communications Technology outsourcing in Libraries. The paper concludes with recommendations and the way forward. Research limitations/implications – The study was limited to the outsourcing of information technology services in four public university libraries in Kenya, namely, Kenyatta University (KU) in Kahawa, Nairobi; Moi University (MU) in Eldoret; University of Nairobi (UON) in Nairobi; and Jomo Kenyatta University of Agriculture and Technology (JKUAT) in Juja, Thika. This being a qualitative study (and taking into consideration the subjective views where bias could occur), the researchers ensured that the research was reliable by recording and taking notes during the interviews and by using peer-debriefing and professionals in the field to ascertain their views. Practical implications – The paper provides practical insights into outsourcing of Information Technology (IT) services in Public University libraries and information centres in Kenya. This study is useful for university libraries, information professionals, information communication technology professionals and university management. Social implications – The implications of the study are that outsourcing needs to be guided by clear policies that are documented and communicated to all the stakeholders. Originality/value – This research assesses IT outsourcing services in selected public academic libraries in Kenya
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    Temperature dependence of the Hg 6s6p(3P0→3P1) transition induced by nitrogen
    (Elsevier, 1987) Callear, Anthony B; Shiundu, Paul M
    The rate coefficient of the process Hg 6s6p(3P0→3P1) induced by nitrogen collisions has been measured over the range 285 to 340 K. The temperature variation closely matches that of the concentration of N2(v = 1). The results support the electronic to vibrational energy-transfer mechanism for the deactivation of 3P1 to 3P0 by nitrogen.
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    Computer-controlled apparatus for automated development of continuous flow methods
    (1989) Wentzell, Peter D; Hatton, Michael J; Shiundu, Paul M; Ree, Ronald M; Wade, Adrian P
    An automated apparatus to assist in the development ofanalytical continuous flow methods is described. The system is capable of controlling and monitoring a variety ofpumps, valves, and detectors through an IBM PC-AT compatible computer. System components consist of two types ofperistaltic pumps (including a multiplepump unit), syringepumps, electrically andpneumatically actuated valves, and an assortment of spectrophotometric and electrochemical detectors. Details ofthe interface circuitry are given where appropriate. To demonstrate the utility of the system, an automatically generated response surface is presentedfor theflow injection determination of iron(II) by its reaction with 1,10-phenanthroline.
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    Spectrophotometric determination of peroxydisulphate with o-dianisidine by flow injection
    (1990) Shiundu, Paul M; Wade, Adrian P; Jonnalagadda, S. B
    Precise and accurate knowledge of peroxydisulfate ion concentration is critical in industrial polymer production, where it is extensively used as an activator. Its ability to oxidize in either acidic, neutral, or alkali media also makes it widely applicable in many other areas of chemistry.In this paper we present an optimized spectrophotometric flow injection method for determination of peroxydisulfate. The analyte oxidizes o-dianisidine to form a stable product which has a convenient absorbance maximum at 450 nm. This provides a simple and sensitive alternative to present methods which are more costly, tedious, or complex. Keywords: spectrophotometric method, peroxydisulphate
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    Spectrophotometric determination of palladium with sulfochlorophenolazorhodanine by flow injection
    (1990) Shiundu, Paul M; Wentzell, Peter D; Wade, Adrian P
    Sulfochlorophenolazorhodanine (as its sodium salt) has been used in the automated development of a sensitive flow-injection procedure for the spectrophotometric determination of palladium. The resulting method has high sample throughput, good precision, and low consumption of both sample and reagents. The optimum pH for the reaction is 5.0 and the response is constant at pH between 4.7 and 5.3. The sensitivity (calibration slope) of the procedure is 4.4 × 103 l./mole. The linear dynamic range is 0.045–30.0 μg/ml. The sample throughput is at least 120/hr. An automated procedure for optimization of analytical variables is described and a two-variable response surface for the system is given. Interference studies on 19 metal ions show that the method has good selectivity.
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    Automated exploration and exploitation of flow-injection response surfaces
    (Elsevier, 1990) Wadell, A.P; Shiundu, P.M; Wentze, P.D
    Three-dimensional plots of instrumental responses vs. chemical concentrations or flow parameters have been 1 obtained in an automated manner on a computer-controlled flow-injection methods development system. Consideration of several alternative responses for flow-injection systems is shown to help characterize a chemistry more thoroughly and reveal the best experimental conditions. One may see the effects of individual experimental variables (reagent concentrations, pH, flow-rates, etc.), the interactions of these variables, instrumental factors and limitations of the surface exploration procedure employed. Chemical systems studied were the photometric determination of phosphate, palladium(II), iron(II) and persulfate. The propriety of automated response surface mapping is demonstrated and the efficacies of simplex and grid search approaches to response surface exploration are contrasted. Responses obtained include absorbance at peak maximum, relative standard deviation of maximum absorbance, time from injection to peak maximum and wavelength of maximum absorbance. Higher dimensional response surface representations of peak shape and absorbance spectra are also presented. The results show that the response chosen governs the general shape of the surface and the height at any point. This approach to automated characterization of chemical reactions in flow analysis is critically assessed
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    Versatile IEEE-488 data acquisition and control routines for a diode array spectrophotometer
    (1991) Shiundu, Paul M; Wade, Adrian P
    The UV-visible diode array spectrophotometer is a work-horse instrument for many laboratories. This article provides simple data acquisition and control routines in Microsoft QuickBasic for a HP-8452A diode array spectrophotometer interfaced to an IBM PC/XT/AT, or compatible, microcomputer. These allow capture of full spectra and measure absorbance at one or several wavelengths at preset time intervals. The variance in absorbance at each wavelength is available as an option.
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    Spectrophotometric method for determination of sulfide with iron (III) and nitrilotriacetic acid by flow injection
    (Elsevier, 1992) Kester, Michael D; Shiundu, Paul M; Wade, Adrian P.
    A manual colorimetric method for determination of sulfide has been adapted to flow injection, systematically optimized, and more fully characterized. Its intended application is for measurement of sodium sulfide reagent strength in pulp process streams, and sulfide contamination in effluent from Kraft pulp mills. In the flow-injection method developed, a sample solution containing sulfide is reacted with a mixture of iron(III) and nitrilotriacetic acid under ammoniacal conditions. The absorbance of the intensely-colored green product of this reaction is measured at 636 nm. Excess sulfite is present as a color stabilizer. A linear dynamic range of 20–100 ppm sulfide is readily achieved; the relative standard deviation is less than 1.2% (n = 10) throughout this range, and 0.37% (n = 10) midrange at 60 ppm. The usable dynamic range is 8–250 ppm sulfide. Long-term stability of the method is ensured by periodically performing an automatic cleaning cycle using a hydrochloric acid wash solution. This prevents tube discoloration and removes any precipitates which are formed under strongly alkaline conditions. The sample throuhput rate is at least 30/hr, given alternate acid wash cycles.
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    Influence of bulk and surface composition on the retention of colloidal particles in thermal field-flow fractionation
    (Elsevier, 1995) Shiundu, Paul M; Giddings, J. Calvin
    In this paper we report a wide range of cases in which the retention of colloidal particles in thermal field-flow fractionation (FFF) shows a strong dependence on the chemical composition of the particles or of the particle surfaces. These results are observed among similar particles (such as different latexes) or between dissimilar particles (including latexes as well as inorganic and metallic colloids). These compositional effects are observed for particles suspended in both aqueous and nonaqueous carrier liquids. The dependence of retention on composition is complementary to its dependence on particle size, which has been amply demonstrated in previous studies. The compositional effect is attributed to the dependence of the thermal diffusion coefficient on compositional factors. A number of cases are presented here where compositional effects are significant. Examples include the baseline resolution of 0.30-μm silica particles and 0.300-μm polystyrene (PS) particles and a large difference in retention times between 0.232-μm PS and 0.229-μm polymethylmethacrylate (PMMA) latexes in aqueous suspensions. Also, metallic particles (e.g., palladium) were less retained than silica particles, with latex particles most retained. The resolution of equal-size particles in the nonaqueous carrier liquid acetonitrile is also demonstrated. Surface compositional effects have also been found in this study. These effects suggest the possibility of colloidal surface analysis by thermal FFF. The potential for performing both bulk and surface compositional analysis of particles by thermal FFF makes this FFF technique complementary to both sedimentation FFF and flow FFF techniques for the analysis of complex particulate materials.
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    Size and compositional studies of core-shell latexes using flow and thermal field-flow fractionation
    (Elsevier, 1995) Ratanathanawongs, S Kim; Shiundu, Paul M; Giddings, J Calvin
    Two field-flow fractionation (FFF) techniques, flow FFF and thermal FFF, have been used as complementary techniques in a study of core-shell latex particles. Different types of physicochemical information about the particles can be obtained since the fields used in the two techniques interact with different particle properties. The hydrodynamic diameters (and diameter distributions) of the latex particles were measured as a function of pH using flow FFF. Retention in thermal FFF was found to depend on shell composition. These FFF techniques, used together, are shown to be capable of characterizing both the physical size and shell composition of this important class of particles.
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    Separation of Particles in Nonaqueous Suspensions by Thermal Field-Flow Fractionation
    (1995) Shiundu, Paul M; Liu, Guangyue; Giddings, J. Calvin
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    Isolation and characterization of polymeric and particulate components of acrylonitrile–butadiene–styrene (ABS) plastics by thermal field-flow fractionation
    (Wiley, 1996) Shiundu, Paul M; Remsen, Edward E; Giddings, J. Calvin
    Thermal field-flow fractionation (ThFFF) is shown here to be capable of isolating the polymeric and rubber particulate components of acrylonitrile–butadiene–styrene (ABS) plastic in a simple analytical procedure. To facilitate the separation, the ionic strength of the two carrier liquids used here (THF and DMF) was brought up to 0.10 mM to increase the retention of the rubber particles. At a field strength (temperature drop) δT of 50 K, the two components were well separated, although the polymer component was not completely resolved from the void peak due to its low molecular weight. To facilitate a more rapid separation of the components, both field programming and high flow-rate conditions were examined in some detail. Both the particle-size distribution (PSD) of the rubber particles and the molecular weight distribution (MWD) of the polymer components were obtained using ThFFF. Measured MWD and PSD agreed favorably with PSD determined by dynamic light scattering and MWD obtained by size-exclusion chromatography.
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    On farm green manure trials: 1997–1998.
    (1998) Kirungu, B. A. M; Kamwana, S; Shiundu, P.M; Kasiti, J
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    An analysis of the opportunities for information technology in improving access, transfer and the use of agricultural information in the rural areas of Kenya
    (MCB UP Ltd, 1999) Kiplang’at, Joseph
    Presented at the SCANUL‐ECS Conference held in Kenya 23‐26 July 1998. Examines the opportunities of information technology (IT) in improving access, transfer and use of agricultural information in the rural areas of Kenya. This paper has used the term “information technology” to include CD‐ROM, computer networks, desktop publishing, interactive video, packet radio, expert systems, geographical information systems and satellite communications. The methodology adopted by the study was the use of case studies of the organisations and institutions that use IT in disseminating agricultural information to the rural population in Kenya. The study was limited to agricultural information. The information technologies examined include CD‐ROM, computer networks, video and desktop publishing. Highlights the advantages and limitations of IT in disseminating information in the rural areas of Kenya. Among the factors that make IT relevant for rural development are vast storage, fast and inexpensive communication channels, links between different media, easy and enjoyable use at comparatively and steadily declining costs. Concludes that for IT to have more impact on rural development, it should be needs driven, rather than technology driven. This can only be achieved if the needs of the users are placed at the centre and appropriate technologies adopted.
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    Thermal stability of Vernonia galamensis seed oil
    (2000) Wamalwa, Benny M; Njuguna, Esther N; Shiundu, Paul M; Kamau, Geoffrey N
    The physicochemical changes of refined vernonia oil?RVO (which naturally contains epoxidized triglycerides) upon heating was evaluated and is reported in this manuscript. A boiling point range of 183 °C to 190 °C (at 760 mm Hg) for the vernonia oil was obtained using the Siwolobboff's method. The oil changed its physical appearance and consistency in the course of the heating. A homogenous free?flowing beige?sand shade refined vernonia oil at room temperature (25 °C) was transformed irreversibly to an intense?brown shade, becoming increasingly more viscous with increase in temperature, and ceasing to flow momentarily at 188 °C. On cooling to room temperature, the oil solidified into a brown rubber?like elastic material. The oil also exhibited a reduction in its oxirane content from 1.39±0.004 equivalent HBr kg?l at 25 °C to 0.542±0.002 equivalent HBr kg?l at 70 °C. This signifies a 61% drop in oxirane content for the 45 °C temperature rise. These findings point towards a thermally driven polymerization and/or decomposition of the refined vernonia oil (RVO).
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    A Conceptual Framework for Research in Music and Music Education within a Cultural Context
    (2001) Akuno, EA
    Music education in Kenya has been, and continues to be conducted along Western theories which fall short of defining music as experienced within traditional African cultures (New, 1980; Omondi, 1980; Kwami, 1989; Akuno, 1997; Kidula, 1998). Research in music, an attempt to find reality and meaning in it, involves discovering its components, how they make a cohesive and comprehensible whole, and how the produced item functions in the economy of the culture thai produces and consumes it. Since music must be understood from the participants' point of view, a true understanding involves analysis within the context in which it is created and practised. The created music is influenced by the artist's understanding of the subject through experience and knowledge gained in that genre. Such experience, gained from casual, informal contacts or deliberate, organised instruction, is drawn upon for musical creativity as manifested in performance, response to musical stimuli as well as composition. This paper examines this process to come up with a conceptual framework for the understanding of music within a cultural context
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    FACTORS AFFECTING PARTICLE RETENTION IN THERMAL FIELD-FLOW FRACTIONATION
    (2002) Shiundu, Paul M; Munguti, Stephen M; Wamalwa, Ben. M
    In this paper, we report a range of factors which affect the retention of colloidal particles in thermal field-flow fractionation (ThFFF). These results are observed among different sizes of polystyrene (PS) latex particles suspended in both aqueous and nonaqueous liquid carriers and very low density lipoproteins in a phosphate buffer. These factors include particle size and chemical composition, field strength, cold-wall temperature of the channel and the nature of the suspension medium. These results show that ThFFF can be used to fractionate colloidal particles according to size and that for an unknown colloidal sample material, a calibration curve must be obtained using particles of similar composition. This is necessary because the degree of retention of the colloidal material is dependent on chemical composition of sample material as evidenced by the chemical composition study. The potential of using ThFFF for physico-chemical characterization of colloidal material is illustrated through the evaluation of thermal diffusion coefficient of PS particles as a function of size, cold-wall temperature, and carrier solution composition. The tunabiliy of the extent of retention of the colloidal particles in a ThFFF channel is illustrated by results of the influence of field strength on retention.