http://repository.tharaka.ac.ke/xmlui/handle/1/4345 2026-05-25T13:22:34Z http://repository.tharaka.ac.ke/xmlui/handle/1/4462 IMPEDIMENTS TO YOUTH ENTERPRISE DEVELOPMENT FUND LOAN REPAYMENT AMONG YOUTH GROUPS IN THARAKA NORTH SUB COUNTY, THARAKA NITHI COUNTY, KENYA MUTEGI, JUDITH K This study examined the impediments to youth enterprise development fund loan repayment. Studies show that youths successfully repay loans consistently in the initial months after being awarded loans, but default there-after for reasons that are virtually unknown. Lack of steady repayment until the principal loan sum is fully cleared provides a breach that this study pursued to explore. This study set out to examine how entrepreneurship training, socio-economic factors, and business performance influence loan repayment among youth group beneficiaries. It was grounded in Group Lending Theory and Social Traits Theory; frameworks that explore how shared accountability and individual characteristics shape financial behavior. A descriptive research design was used, drawing on primary data sources. The research targeted 16 registered youth groups, including YEDF beneficiaries and fund officers. From this population, a stratified random sample of 123 respondents was selected. Data were collected through structured questionnaires and interviews, then analyzed using the Statistical Package for Social Sciences (SPSS) 27.0. Both descriptive statistics and thematic analysis were applied to the quantitative data, while qualitative responses were examined through thematic analysis. The findings showed that most beneficiaries reported gains in financial literacy and business management skills following entrepreneurship training. However, several constraints such as limited startup capital, low-income levels, and weak market linkages posed significant barriers to consistent loan repayment. Broader socio-economic challenges also emerged, including high unemployment, a poor culture of saving, and dependence on unstable income streams. In addition, business performance factors like low profitability and inadequate record-keeping were found to have a strong influence on repayment behavior’s study concludes that while the Youth Enterprise Development Fund (YEDF) has expanded access to credit for young people, the sustainability of these gains is undermined by fragile repayment structures and insufficient follow-up after loan disbursement. To address these gaps, the study recommends ongoing entrepreneurship training, increased loan amounts tailored to real business needs, stronger post-loan monitoring systems, and improved collaboration between YEDF and local actors to boost accountability and compliance. These findings offer valuable insights for policymakers, development practitioners, and researchers seeking to strengthen youth credit systems and advance inclusive economic empowerment strategies. 2025-11-01T00:00:00Z http://repository.tharaka.ac.ke/xmlui/handle/1/4461 A STUDY ON PERFORMANCE EVALUATION OF STABILIZED EXPANSIVE CLAY SOIL WITH SORGHUM HUSK ASH CEMENT BLENDS IN NKONDI, KENYA KATHENYA, FESTUS K Expansive soils, which are widespread globally, are a major cause of structural damage such as cracks in buildings, roads, and pavements. Stabilizing these soils is essential to minimize their plasticity, shrinkage or swelling potential, and thus improve their strength and durability. One of the most common approaches to soil stabilization is chemical treatment, where chemical additives are mixed with the soil to trigger a chemical reaction. Ordinary Portland Cement (OPC) has been the most widely used additive for stabilizing expansive soils. However, its high cost makes it less accessible to low-income populations, particularly in developing nations. Additionally, the production of OPC is a major environmental concern, contributing 5-8% of the global human-made carbon (IV) oxide emissions. The study examined the performance of expansive clay soil stabilized with sorghum husk ash (SHA) blended cement. Soil samples were collected from Nkondi ward in Tharaka Nithi County, Kenya at varying depths of 0–30, 30–60, and 60–90 cm, while sorghum husks were obtained from Mwanyani location in the same ward. The clay soil was characterized before and after calcination to establish mineralogical and chemical properties. The clay soil samples were calcined at a temperature of 700 oC for 2 hours in a furnace to transform the unreactive kaolinite mineral into metakaolin, which is the reactive phase. The sorghum husks samples were burnt in a furnace to produce the ash at a temperature of 600, 700 and 800 oC for 2hours each. Clinker, limestone, and gypsum were sourced commercially sourced from Ndovu cement company. Sorghum Husk Ash and calcined clay was incorporated in cement by substituting clinker from 40 to 80% in three samples labelled as S2, S3 and S4. S2 was prepared by combining 80% clinker, 15% limestone and 5% gypsum totaling to 100%. The rest of the samples were prepared by reducing clinker to 40% with varying proportions of calcined clay and SHA, while gypsum and limestone contents were fixed at 5% and 15% respectively totaling to 100%. S1 soil sample was the unstabilized clay soil. The stabilized soils were tested for compaction, Atterberg limits, linear shrinkage, particle size distribution, and California Bearing Ratio (CBR). X-ray diffraction (XRD) results indicated that raw clay samples contained kaolinite, quartz, and feldspars. Calcination reduced kaolinite phases, with increased amorphous aluminosilicate phases observed. X-ray fluorescence (XRF) analysis of calcined clay showed an increase in silica and alumina oxides, enhancing pozzolanic potential. The chemical composition of sorghum husk ash burnt at 700 oC for 2 hours showed silica at 68.93%, alumina at 3.3%, and ferric oxide at 3.85%, giving a combined total of 76.08%, which satisfied the pozzolanic criteria. Grading was done by particle size distribution and the results showed that 4.0% of soil was retained on the 10 mm sieve, 4.7% on the 5.0 mm sieve, 3.5% on the 2.0 mm sieve, 1.9% on the 1.0 mm sieve, 5.5% on the 0.425 mm sieve, and 17.8% on the 0.075 mm sieve, with 62.6% passing the pan. Proctor compaction gave a maximum dry density of 1.601 gcm-3 and optimum moisture content of 20.8%. The natural moisture content was at 11.6%. California Bearing Ratio (CBR) results at 2.54 mm penetration were as follows; S1 recorded 21.2% at 10 blows, 64.8% at 30 blows, and 80.1% at 65 blows. S2 yielded 23.8%, 77.0%, and 90.6% under similar conditions. S3 exhibited 15.5, 26.0, and 45.9% while swell potentials reduced to 3.69, 0.01, 0.33, and 0.45% respectively. Atterberg limit tests showed liquid limits of 48.8 (S1), 44.3 (S2), 46.4 (S3), and 45.6% (S4), with constant plastic limit of 28% across samples, producing plasticity indices of 16, 18, and 17% respectively. Linear shrinkage values were 14% for S1, 9% for S2, 10% for S3, and 11% for S4. This study aimed to develop an eco-friendly construction material by increasing soil strength using sorghum husk ash 2025-11-01T00:00:00Z http://repository.tharaka.ac.ke/xmlui/handle/1/4459 DETERMINATION OF CHEMICAL COMPOSITION AND LARVICIDAL EFFICACY OF ESSENTIAL OILS OF Cymbopogon citratus, Chrysanthemum cinerariifolium AND Rosmarinus officinalis IN MERU AND THARAKA NITHI COUNTY AGAINST Aedes aegypti (DIPTERA: CULICIDAE) KITHETU, BENARD M Aedes aegypti is the mosquito species responsible for the viruses that cause yellow fever, zika disease, chikungunya fever and dengue fever. The four diseases have no cure, necessitating mosquito control as the proven ways of minimizing human vector contact eventually lead to reduced infections and prevalence rates of these diseases. The existing methods employ the use of insecticides, which present a number of challenges, including resistance, toxic hazards to the environment, non-target organisms, and humans. This study aimed to determine the chemical composition and larvicidal potential of essential oils extracted from Cymbopogon citratus, Chrysanthemum cinerariifolium, and Rosmarinus officinalis against Aedes aegypti larvae. These plants are preferred because of their earlier applications, traditionally as insecticides and pesticides. Plant materials (twigs, flowers, and leaves) were collected from Meru and Tharaka Nithi Counties, Kenya, and subjected individually to hydro-distillation for essential oil extraction. The chemical constituents of the oils were analyzed using a Thermo-Scientific Trace 1310 GC-MS system, and retention indices were calculated from mass spectra. The analysis revealed that C. cinerariifolium contained the highest number of compounds, predominantly the sesquiterpenes; α muurolene (30.98%) and β-farnesene (27.73%). R. officinalis was rich in the monoterpene α-pinene (21.96%), and the monoterpenoid eucalyptol (20.04) while C. citratus was dominated by the monoterpenoids; geranial (28%) and neral (19.01%). Bioassays demonstrated significant larvicidal activity, with C. cinerariifolium exhibiting the highest potency (LC₅₀ = 0.003 mg/L at 24 h), achieving 100% larval mortality at concentrations as low as 0.1 % concentration. R. officinalis (LC₅₀ = 0.056 mg/L at 24 h) and C. citratus (LC₅₀ = 0.610 mg/L at 24 h) also displayed activity, The LC50 and LC90 of R. officinalis and C. Citratus have no significant difference in the first 24 hours while C. cinerariifolium shows a significant difference and much lower, indicating that C. cinerariifolium is most potent though less pronounced. Therefore, essential oils from the three plants can be applied at different concentrations to counteract A. aegypti larva. The findings of this study show that the presence of sesquiterpenes in the essential oils increases the potency of A. aegypti larva, highlighting the potential of these plants, especially C. cinerariifolium, as promising natural alternatives for mosquito vector management 2025-11-01T00:00:00Z http://repository.tharaka.ac.ke/xmlui/handle/1/4458 MODELLING FLUID FLOW IN AN OPEN CIRCULAR CHANNEL WITH THREE LATERAL INFLOWS MUCUNKU, MISHECK M Kenya has been experiencing heavy rains in recent years, leading to significant flooding challenges. A flood happens when water spills over and covers land that is usually dry. Flooding can happen gradually over a long period or very quickly, within minutes. Floods are the most common natural disaster globally, causing extensive damage to properties and infrastructure. Therefore, there is a need to construct channels that divert water into rivers, lakes, and the ocean to reduce flooding. Many researchers are working to design drainage systems, navigation channels, irrigation canals, and ditches to efficiently convey water and generate hydroelectric power. Circular - shaped channels with three inflows have received less attention in open channel flow studies than rectangular, parabolic, trapezoidal, and horseshoe - shaped channels. This study aimed to model fluid movement in an open circular conduit that contains an incompressible Newtonian fluid and has three lateral inflows. Also, the research investigated consequences of raising length of the lateral entry channels, the lateral inflow’s angle channels (ranging from 0 0 to 900) on the cross - sectional area and the primary open channel’s velocity.Flow was controlled by the continuity and momentum equations. Via the application of a similarity transformation, these equations were changed to a set of ordinary differential equations that are non - linear. Following that, the finite difference approach was used to solve the resultant system numerically. Python software was used to analyse the results obtained from this study for the hydraulically efficient open circular channels, The results were subsequently presented in graphical form. The equations were first represented in dimensionless form. The findings showed that when lateral inflow increased, the main channel’s velocity decreased. Furthermore, it was noted that the velocity decreased as the lateral inflows’ angles increased. Similarly, the principal channel’s velocity decreased as the cross - sectional area of the lateral inflows increased. It is hoped that the findings of this study would be helpful to engineers when designing open circular channels with three lateral inflows that maximize hydraulic efficiency and water transfer capacity. These channels could be utilized for various applications, including flood mitigation, hydroelectric power generation, irrigation, and high - speed water operations in water mills 2025-11-01T00:00:00Z