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Item Physicochemical characterization and genetic diversity studies on selected rice (oryza sativa l.) Genotypes based on gel consistency and alkali digestion(Kenyatta University, 2016) Chemutai, Lagat RoseKnowledge of rice genetic diversity is necessary to ascertain the germplasm conservation and the development of improved rice genotypes with good quality traits through various breeding programs. Blending of rice with good and poor quality traits by unscrupulous traders to make enormous profits causes a negative impact on the consumer preference and the rice trade. The aim of this study was to determine the physicochemical characterization and the genetic diversity based on gel consistency and alkali digestion among selected Kenyan and Tanzanian Oryza sativa genotypes using the SSR markers. In this study physicochemical test were conducted to determine the alkali digestion values and gel consistency of the 12 rice genotypes studied. Genetic diversity based on the gel consistency and alkali digestion using the 8 SSR markers that are tightly linked to the quantitative trait loci’s (QTLs) controlling these traits was also determined. Minitab 17.0 software package was used to determine the means and the standard error of means of the gel consistency physicochemical test results while the alkali digestion values were determined based on the standard evaluation system by International Rice Research Institute. PowerMarker version 3.25 was used to determine the major allele frequency, allele number, gene diversity and the polymorphic information content (PIC). GenAlEx version 6.41 was used to determine the principal coordinate analysis (PCoA) and analysis of molecular variance (AMOVA). DARwin 6.0.12 statistical software was used to determine the genetic dissimilarity matrix based on Jaccard’s coefficient with 1000 bootstrap values and to draw an unweighted neighbour joining tree. The rice genotypes were classified into various classes based on the existent standard evaluation systems. The number of alleles per locus ranged from 2 to 4 with an average of 2.75 across the 8 markers used. Polymorphic information content (PIC) ranged from 0.5224 (RM577) to 0.1411 (RM85) with an average of 0.3673 observed across all the markers. Gene diversity ranged from 0.5764 (RM577) to 0.1528 (RM85) with an average of 0.4181 with one rare allele was detected using RM577 loci. Pairwise genetic dissimilarity matrix ranged from ranged from 0.9333 to 0.1818 with the least genetic distance being observed between IR 54 and BS 370 while the highest, 0.9333 being between Saro 5 and IR 2793. The unweighted neighbour joining tree clustered the rice genotypes into three major clusters and subsequent sub clusters hence effectively differentiating the Kenyan and Tanzanian genotypes based on gel consistency and alkali digestion. These clustering was complemented with the findings in the principal coordinate analysis. These results show that determination of genetic diversity using SSR markers that are tightly linked to the QTLs and physicochemical characterization can be effectively utilized in analysis of diversity in rice germplasm.Item Determination of some trace elements with known immunological response and curative properties in some selected medicinal plants(2014) Njenga, Isaac KariukiThe emergence of drug resistant diseases coupled with the ever-nsmg cost of drugs and difficulties in assessing health care in Kenya has resulted in an upsurge of interest in herbal plants. Many sythentic drugs among them artemesinin used for malaria treatment have been derived from herbal plants.There has been a great emphasis on analysis of organic compounds in the herbal plants over the years.These bioactive compounds are part of the plant matrix which include the trace elements. Some trace elements have known immunological response and curative properties which might explain the efficacy of the herbal plants and thus the significance of this study. This study will be carried out to determine the concentrations of trace elements with known immunological response and healing properties in selected medicinal plants available in Kenya and used for treating various diseases. These plants are Prunus Africana (Hook f.) Kalkman,Urtica doica L., May ten us obscura (A. Rich.) Cuf., May tenus putterlickiodes, Azadiracta indica A. Juss , Mondia whytei (Hook. F.) , Zanthoxylum usambarense, Maerua edulis (Gilg & Gilg-Ben) , Trigonella foenum-graecum L. and Glycyrrhiza glabra . L. The last two are common exotic species.The concentrations of Zinc, Chromium, Vanadium and Selenium will be determined by the use of Atomic Absorption Spectroscopy (AAS) and Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF). The data will be analysed using SPSS and Ms Excel computer software. Spectral data analysis for EDXRF elemental concentration will be done using QAES, AXIL and S-100 computer software. The information obtained will be used to enhance the indigenous knowledge of the medicinal plants through dissemination to the public and health care providers.Item Vitro antimicrobial activity and safety of medicinal plants used to manage samonella typhi, campylobacter jejuni and shigella dysenteriae in Meru county, Kenya(Kenyatta University, 2014) Maithulia, Stephen MugambiPlants have been used in the management of human enteric bacterial pathogens (that causes bacterial gastroenteritis) without scientific evaluation on their antimicrobial activity, safety and efficacy. The main goal of this study is therefore to evaluate in vitro antimicrobial activity of aqueous extracts of Osyris lanceolata, Mimosa pudica and Zanthoxylum usambarense and assess their safety using the rat's model. The aqueous extracts will be evaluated in vitro on their activity against gram-negative enteric bacteria (Salmonella typhi, Camphylobacter jejuni and Shigella dysenteriae) using the Agar Disk Diffusion Method, MIC, MBC and Time Kill Kinetics. The safety of the extracts will be assessed by administering orally and intraperitoneally aqueous extracts of the three plants at 450, 670 and 1000g/kg body weight daily to rats for 28days and recording the changes in body and organ weight, hematological and biochemical parameters and histopathology. The phytochemical composition of the aqueous plant extracts will. be studied using standard qualitative and quantitative procedures and the mineral composition of the. aqueous plant extracts will be assessed using Energy Dispersive X-ray fluorescence system (EDXRF). The obtained results will be expressed as Mean±SEM and analyzed statistically using ANOVA and POST-ANOVA to compare the means to aid in comparing Antimicrobial activity of the different plant extracts. The results obtained will be used to prepare scientific report on antimicrobial activity of Osyris lanceolata, Mimosa pudica and Zanthoxylum usambarense and the recommendations for continued use or otherwise will be made based on the outcome for the study. In addition, the outcome of the study may necessitate recommendations for further study on the management of bacterial gastroenteritisItem A nano-based electrochemical immunosensor for rapid and sensitive diagnosis of schistosoma in Kenya(Kenyatta University, 2014) Odundo, Joseph O.Schistosomiasis also known as Bilharzia is caused by the parasites of the species Schistosoma and is one of the 17 Neglected Tropical Diseases (NTDs). It affects over 950million people in the world with Africa being the most affected due to escalating levels of poverty. In Kenya, it affects about 20 million people whose economic activities involve direct contact with otherwise infected waters. The effect of the disease becomes complicated with time and therefore early detection using a very sensitive and accurate method is important in its treatment and management. Its diagnosis currently is performed by microscopic detection of eggs (in urine or stool) or by immunological methods (antibody or antigen detection). However, these methods suffer low sensitivity and occasionally give unreliable results especially in low prevalence areas. This study sets to develop a versatile and sensitive electrochemical technique based on Silver (Ag) and Gold (Au) nano-particles (NPs) for detection of Schistosomiasis soluble egg antigens (SEA) in excreta from infected individuals. The nano-imrnunosensor will consist of a biolayer of Ag/Au-NPs conjugated to anti-schistosoma antibodies or SEA. The conjugate will be characterized by UVNis and Cyclic Voltarnmetry(CV) before immobilizing on a sensor platform. The molecular recognition of NPs-Antibody or NPs-SEA conjugate with an enzyme will be studied using Enzyme Linked Immunosorbent Assay (ELISA) and the analytical signal arising from this characterized electrochemically using CV. The signal will be relayed to a micro-processor and eventually to a display. This response signal is rapid, specific and fast enough to give real-time diagnostic results for Schistosomiasis. The data obtained on reliability, precision, selectivity and sensitivity tests shall be subjected to standard statistical analysis procedures.Item Behavioural and environmental highland malaria risk factors analysis in Nyamira North district, Nyamira County(Kenyatta University, 2014) Okonji, Gilbert, AsilenjeMalaria is caused by protozoan parasites of the genus Plasmodium. It is one of the leading causes of illness and death and one of the most important causes of human morbidity and mortality with enormous medical, economic and emotional impact in the world. Estimates indicate that there were about 207 million cases of malaria and an estimated 627 million deaths. Nyamira North District lies in the western Kenya highland and is known to be a malaria epidemic area with unstable transmission of varying seasonality. The highest peak of malaria transmission is usually reached between May - July and November-January periods preceding the short and long rain seasons. The current study aims to investigate the correlation between environment and household's knowledge, attitudes and practices with malaria epidemics in Nyamira North District. 890 participants of all ages (all-age cohort) from the study area will be enrolled. Data on environmental, socio-demographic, and economic factors will be collected from 21villages systematically selected. Environmental data will be collected from Olobal Positioning System (OPS) measurements. The dwelling in which the participant normally sleep will be assessed and distances to mapped forest edge, swamps, rivers, roads, and health centers will be calculated. Type of vegetation within 200 m of the house will be recorded. The presence and type of slope will also be determined. A questionnaire will be orally administered to ascertain socio-demographic, economic and behavioral characteristics. To establish whether there is any statistical relationship between the mentioned variables and malaria prevalence, Pearson Chi- square test will be used. An association between the two variables will be considered significant if the p value~0.05. Data generated by the study will be used by the Ministry of health in future control strategies for highland malaria in Nyamira North district.Item Performance of rapid immunochromatographic test and microscopy in determination of malaria prevalence among expectant women in Kericho county hospitals, kenya(Kenyatta University, 2014) Njeru, Annastasia WangariMalaria, a parasitic infection transmitted by mosquitoes, is one of the most devastating infectious diseases and contributes very significantly to maternal and foetal mortality. Microscopic analysis has been the standard diagnostic technique for identifying malaria infections for more than a century but is unable to detect all infections as parasites can be sequestered in the placenta. Good quality microscopy is also lacking in many resourcelimited settings, as it requires well-trained, competent personnel, infrastructure as well as effective quality control and assurance. It is also labour-intensive and time-consuming, sensitivity decreases as the density of malarial parasites in the blood decreases. The problems associated with implementing and sustaining a high level of skilled microscopy appropriate for clinical diagnosis, particularly in the field setting, have prompted the development of a variety of technologically simple malaria rapid diagnostic tests. Rapid immunochromatographic test may provide a solution as emerging evidence suggests that they are capable of detecting Plasmodiumfalciparum which sequesters in the intervillous space of the placenta better than microscopy. The proposed study aims at evaluating the performance of the rapid immunochromatographic strip test and microscopy in determination of malaria prevalence during pregnancy using polymerase chain reaction as a confirmatory test. The study targets the primary health care setting using Kericho District Hospital, Kipsitet and Fort Ternan Health Centres which represent resourcelimited setting, reliant on microscopy as malaria diagnostic test. They lack well-trained, competent personnel, infrastructure as well as effective quality control and quality assurance to make accurate diagnosis. Participants will be drawn from a population of pregnant women aged 18 years and above, who have malaria symptoms and are not on antimalarial drugs attending antenatal care visits. Using microscopy as the gold standard, Polymerase Chain Reaction as a confirmatory test, the sensitivity, specificity, negative predictive value and positive predictive value of the IC test will be determined. The prevalence of malaria among expectant mothers will also be determined using microscopy and rapid ICTs. Data analysis will be done using SPSS version 17. McNemar's Chi square statistic will be used to test the level of agreement between the two tests. The findings of this study will be crucial in determining the suitability and reliability of rapid immunochromatographic test that will allow community health care workers to make rapid and accurate diagnosis of malaria in expectant mothers and make immediate therapeutic decisionsItem Plasma interleukin- 10 levels in HIV and HBV co-infected adults From Mombasa county, Kenya(Kenyatta University, 2014) Otieno Hellen Achieng'I-Iuman Immunodeficiency Virus-I (HIV -1) and Hepatitis B Virus (HBV) co-infection is 4 common public and clinical health burden in Kenya. This is because these blood borne pathogens share modes of transmission. Drug users, especially injecting drug users (IDUs), are at a higher risk of acquiring and transmitting these viruses because they often share unsterilized I syringes and engage in risky sexual behaviors. Mombasa County serves as the entry and transit point for drugs and consequently have the highest number of IDUs. Co-infection with HlV-1 and I-IBV results in severe disease outcomes and rapid progress to AIDS. Following HBV infection, HlV-1 infected patients are six times more at risk of developing chronic hepatitis B than HfV-1 negative individuals. HIV -1 also enhances the development of HBV related liver diseases. Interleukin 10 is an immunoregulator cytokine that function to control the balance between immunopathology and protective responses in infection. Interleukin 10 is usually associated with antiviral immune response suppression. Both HIV -1 and HBV infections up regulate It 10 expression which in turn controls various aspects of the infection processes. Despite the importance of lL-l 0 in disease progr~ss, little is known about the role it plays in IIIV-1 and IIBV co-infection pathology mechanisms. Therefore, a cross sectional study will be conducted at Bomu Medical Centre, Mombasa County to determine the levels of circulating IL- 10 and their effect on immunological correlates in HIV -1 and HBV co- and mono-infected adults in Mombasa County. lL-10 levels will be measured using lL-l 0 enzyme linked immunosorbent _, assay. The samples will be tested for HIV -1 using Abbott Determine® HlV -1/2 rapid test and confirmed using Uni-Gold® test. HBsAg presence will be determined using one-step HBV-5 panel rapid diagnostic kit. The viral loads will be determined using polymerase chain reaction. CD4 T cells will be enumerated using FACSCalibur machine. Basal metabolic index will be calculated using the height and weight measurements of the study subjects. The data collected will be analyzed using SPSS (version 22) and GraphPad Prism (version 6.0) statistical programs. Across groups comparison will be done using Kruskal Wallis whereas paired groups comparison will be done using Manu-Whitney U test. Spearman's rank correlation test will be used to determine the relationship between IL-I0 and CD4 T cells, viral load and basal metabolic index. A probability of :S0.05 will be considered statistically significant. The results obtained will help in improving the understanding of HIV and HBV co-infection pathology and development of new therapies that can be effective against the coinfection and vaccinesItem Investigation of anticancer activity of selected plants among uvaria scheffleri, artemisia afra and azadiracht a indica against breast and prostate cancer cells lines(Kenyatta University, 2014-11-28) Maina, Gladys WanjiruCancer is one of the major non-communicable diseases (NCDs) and it is estimated to kill over 8 million people globally every year constituting close to 13% of total deaths worldwide. In Kenya, cancer ranks third as a cause of death after infectious diseases and cardiovascular diseases. It causes 7% of total national mortality every year. Although population based data does not exist in the country, it is estimated that the annual incidence of cancer is about 28,000 cases and the annual mortality to be over 22,000 persons. To date, many anticancer drugs have been developed and applied to cancer patients. However, resistance to anticancer drugs has been reported and this treatment is neither available nor avoidable to the poor and marginalized communities. Synthesis or modification of known drugs continues as an important aspect of research, but the relatively small improvement over the prototype drugs, which have resulted from the vast amount of synthetic work, is discouraging. Therefore, research and development of new and safe drugs is necessary for the pharmaceutical industry. The long established use of vinca alkaloids (Vinblastine and vincristine), etoposides, taxanes and the isolation of the cytotoxic podophyllotoxins as highly effective anticancer agents demonstrate that plant species are an important resource for the discovery for novel natural anticancer agents. Kenya is endowed with a rich diversity of tropical rainforest plants, some of them being used traditionally as herbal remedies. In addition, there is an abundance of extremely biodiverse population of plant species that have not been subjected to anti-tumor activity assays for the advancement of cancer treatment. It is therefore necessary to evaluate the traditional anticancer plants with the aim of incorporating them into the national health care systems or discovering new potent cytotoxic molecules which may be developed into drugs or may be used as templates or leads for synthesis or development of new more potent synthetic analogues. In search for new antitumor principles, three plants namely of Uvaria schejjleri Diel, Azadirachta indica Juss and Artemisia afra Jacq-ex wild normally used to treat cancer and other ailments in Kilifi and Meru County will be investigated. The crude extracts and the bioactive active principles will be screened for in vitro anticancer activity against breast (DU-4475) and prostate (DU-145) cancer cells lines. Isolation and purification of bioactive principles present in the active extracts will be done using chromatographic techniques (CC, TLC, Prep TLC). The chemical structures will established conclusively by using UV, IR, MS and extensive IH and l3C NMR spectra analysis and comparison with data from the cited literature. 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT - microtiter plate assay) will be used to determine the cytotoxicity of agents tested against various cell lines. Therefore, the current study seek to investigate the anticancer activities of extracts of the three plants against human breast and prostate cancer cells.Item Physiological and molecular responses in adult and larvae anopheles gambiae s.s. to murraya koenigii phytochemicals(Kenyatta University, 2014-11-28) Mang'era, Clarence MaikuriContinuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non-target organisms including human health. Naturally occurring plant compounds and their derivatives are, therefore, of increasing interest for the development of new compounds against the malaria vector. In this study, adulticidal and larvicidal activity of essential oil and crude extracts isolated from the leaves of Murraya koenigii against mosquito vectors will be investigated. Essential oil will be isolated from the leaves of M koenigii using hydro-distillation method. Different compounds will be identified by gas chromatography-mass spectrometry analysis. Larvicidal activity of crude chloroform, dichloromethane and methanol extracts of the leaves will be tested against the early fourth instar larvae of Anopheles gambiae s.s. and larval mortality observed after 24 h of exposure relative to the positive control Temephos, an effective emulsifiable concentrate larvicide. Susceptibility tests on adult mosquitos will be carried out using WHO insecticide susceptibility standard procedures. The fumigant toxicity assays will be repeated with commercially available constituents of the essential oils and blends of these at their natural proportions in the oils and in amounts present in the minimum 100% lethal dose of the oils. Each component will then be subtracted from the blend in turn to determine its relative contribution to the overall toxicity of the natural oil. RNA will be extracted from mosquito stages exhibiting unique response to the plant compounds, allowing detection of genes that might show differential expression in a constitutive and/or inducible way. The extracted RNA will be treated with DNase and the RNA quantified. Three replicate experiments will be performed for each observation. The cDNA libraries will be developed from the extracted RNA and sequenced on illumina platform using established protocols. The libraries will be made from three independent collections from each observation, and will be barcorded for sequencing. Resultant transcriptome sequences will be subjected to quality control checks using FastQC software following which the reads will be mapped to their respective reference genomes and splice junctions between exons identified using combinations of TopHat and Bowtie software. Differential expression and regulation among and between samples from different species will be determined using cufflinks software. Specific methods adopted will be determined by the inherent nature of the data, following standard biometric procedures (e.g normality test where appropriate), and software. Our approach employs the repellent, toxic or otherwise bioactive effects of major components of essential oils through subtraction assays that will provide an additional insight into the relative contribution of these components and potentially explore new targets in the malaria vector that will spur research into novel synthetic formulations.Item Metabolites and hormones as indicators of postpartum reproductive efficiency of pasture based Friesian dairy cows in Kari-Lanet, Kenya(Kenyatta University, 2014-11-28) Indetie, Annah HokaAgricultural production remains the main source of livelihood for rural communities in sub- Saharan Africa, providing employment to more than 60% of the population and contributes about 30% of domestic products. There is a deficit of up to 15 mg /day of metabolisable energy and effective rumen degradable protein of 235g1 day to support desired levels of milk output. This deficit has led to low milk 'production and inefficient reproductive performance of smallholder daily cows. In other parts of the world, influences of Hormones and .metabolites ..on..Iepr.oducti¥€ .perfcrmance .of.daiJ¥ .cattle hase.been .established, In K€ll¥a, information on whether metabolites and hormonal levels are indicators of nutritional levels and reproductive performance of postpartum daily cows is not sufficient. Therefore this study seeks to determine indicators of postpartum ovarian cyclicity in Friesian daily cows. The study will be conducted at KARJ- Lanet within the Rift Valley. Purposive sampling technique will be used to select 30 Friesian cows of parities 1-4 and of body condition score 2-4. The cows will be grazed on Elba Rhodes. Test group cows (20 cows) will be supplemented with 2kg of total mixed ration (TMR) of Bracharia and Dolichos lab lab pre and 4kg of TMR postpartum whereas control group cows (10 cows) will not be supplemented. Water and minerals will be given adlibitum to all cows. Daily milk will be recorded. Cows' weights and •a0dy ,c0nGi~i0n' -seore -will• •re •r-eo0f€led• weekly. •Cal,ving •a0Gy -ceadition will ore recorded. Reproductive data will include days from calving to first observed estrus, days to first service, and conception at first service, and number of services to conception. Blood samples will be aseptically collected into heparinised tubes twice a week from each cow via jugular vein into well labeled tubes and will be centrifuged for 15 minutes at l500xg to give plasma for blood metabolites and hormone analysis. Non-esterified fatty acids, Insulin-like-growth factor-I, will be measured using commercial kits. Twenty milliliters (mls) of evening milk will aseptically be collected into 25mls sample bottles containing sodium azide as a preservative. The milk will be centrifuged at 300 revolutions per minute for 30 minutes and the resulting skimmed milk used for progesterone analysis using lAEAIF AO bench protocal. Plasma Leptin concentration will be determined every 4 days using established methods. Pasture ana .f0tal••mi*ea •rati0B feede -ana-lysi•g -will •ae -done •using wet •chel'Il:-istry to •give chemical composition of the feeds. Milk production, BCS, metabolites and hormonal concentrations will be analysed by mixed procedure (SAS institute Inc. Cary, NC. USA). Turkey Kramer tests will be conducted to analyse differences within and across treatments. Factors affecting the initiation of ovarian cyclicity will be evaluated by regression analysis using backward elimination procedure. The independent variable will be the re-initiation of ovarian cyclicity and the dependent variables will include parity, BCS at parturition, body weight, milk production, total protein, urea, NEFA, IGF-l and leptin. The recommendations of this study could put interventions in place for reproductive efficiency leading to increased milk and meatItem Computational and optoelectronic studies of rare earth metals doped titania for photochromic applications(Kenyatta University, 2014-11-28) Osoro, Mosiori GeoffreyNanofabrication of Ti02 makes it useful in varieties of applications like photocatalysis, photochromic devices, self-cleaning coatings, fog proof glass and water purifier. Titanium (IV)-oxide occurs in nature in three mineral forms: anatase, brookite and rutile. All three forms are characterized with high refractive index, low absorption and low dispersion in visible and near-infrared spectral regions, high chemical and thermal stabilities. This important metal-oxide semiconductor with relatively wide band gap (3.25 eV for anatase, 3.0 eV for rutile, 1.9 eV for brookite) and low phonon energy «700 em") is an excellent host for various rare earth (RE) impurities providing their efficient emission in visible range. These systems are of possible interest in white light emission diode (LED) industry, photocatalysts and photochromic applications. At the same time, being non-toxic and biocompatible, rareearth doped anatase has strong potential to replace standard types of fluorophores (quantum dots, organic dyes, etc.), traditionally used as fluorescent markers in medicine and biological applications. Titanium and Rare earth doped Ti02 nanoparticles will be synthesized by sol gel and wet precipitation method. Theoretical optical properties will be estimated by density functional theory (DFT) using quantum EXPRESSO software, which will be corroborated with experimental data. Morphological and structural properties will be characterized by Scanning electron microscope (SEM), transmission electron microscope (TEM) Energy dispersive X-ray (EDX), X-ray diffraction (XRD), UV-visible spectroscopy, Fourier Transform infrared (FTIR) spectroscopy and photolumnisce spectroscopy.Item Identification and characterization of kenyan marine microalgae strains towards biofuel production(Kenyatta University, 2014-11-03) Musungu, Kathleen KhakasaThe rising global energy demand in both developed and developing countries is heavily straining the limited energy reservoir. The increased use of fossil fuels result in large Green House Gases (GHS) emissions, that are usually considered the main cause of global warming. Microalgae are projected to be the source for the third generation biofuel. The proposed study seeks to identify, characterize microalgae from the Indian Ocean and its environs for biofuel production. Algal strains will beisolated, identified and evaluated for their use in biodiesel production. The methods of isolation will include; Dilution in liquid media (Wahle, TAP and F/2Media) Density centrifugation and addition of antibiotics. The strains will be screened for lipid component using the Ni1e red staining method, while tatty acid profiles will be screened during the selection of suitable candidates. The identified algae will be subjected to WaJne and F/2 Media whose component has potential of influencing lipid production. Both conventional and molecular characterization methods will be adopted to identify the microalgae strains. Conventional methods used will include; microscopy accompanied by the Phytoplankton guide. Molecular characterization will be done using 18S rDNA Sequencing of the Polymerase chain reaction (peR) products will be done using the ABI 3750 capillary electrophoresis machine. GeneMapper software will be used to calculate the allele sizes of the samples. Power Marker version 4.0 software will be used for genetic analysis and construction of a dendrogram to determine the phylogenetic relationship of the isolated algal strains. Suitable candidate strains will be recommended for mass cultivation for mass biodiesel production exploitation. Parametric statistics will be used to analyze the occurrences of micro algae in various locations. Data for growth rates and lipid productivity will be analyzed by Analysis of variance (ANOV A) with different microalgae species as the source of variance and growth rate or lipid productivity as the dependent variable. Scatter plots will be made to establish bivariate relations between the variables and the outcome. Correlation coefficient values v,iill also be obtained between the physico-chemical parameters and phytoplankton abundance and diversityItem Effects of land use practices on namulonge wetland cover, Wakiso district, central Uganda.(Kenyatta University, 2014-11-03) Tumuhimbise, ImmaculateWetlands are amongst the most productive ecosystems in Sub-Saharan Africa; because of their capacity to store, distribute, filter and gradually release large quantities of fresh water stock. However, there has been unsustainable use ofNamulonge wetland due to uncontrolled land use practices resulting into its degradation. This is likely to lead to low crop yields, high cost of agricultural production and reduction in fish stock hence hastening food insecurity and threatening ecological systems in the catchment. Therefore, the main objective of the study is to assess the effects ofland use practices on Namulonge wetland cover, Wakiso District, Central-Uganda. Specific objectives include; to investigate the various land use practices carried out in Namulonge wetland; to analyze the trends in wetland cover from1983 -2013; to evaluate effects of each land use practice on wetland cover. To achieve these objectives, a cross sectional data on land use practices will be collected from 80 households who will be purposively sampled from a total of 424 households using questionnaires. Step-wise regression model will be used to analyse data on the various land use practices carried out in Namulonge wetland. A trend analysis will be done for objective two over the longer term covering Namulonge wetland. Wetland loss and gain will be quantified by computerized (GIS) analysis. Statistical Package for Social Sciences and Microsoft Excel software will be used to draw tables, charts and graphs for analysis. The findings will be presented as tables, charts and graphs from which inferential conclusions will be drawn. The study will provide information that will guide on wetland use, thus adding value to knowledge sharing initiatives within the sub-catchment in the field of wetland conservation studies. Also, the study will provide information about wetland functions and values to sustainably use them to support people's livelihoodsItem Effects of aspergillus niger on mechanical, diffusion and thermal degradation properties of recycled low density polyethylene(Kenyatta University, 2014-10-31) Kamau, Samuel GithiraPlastics have wide applications in our daily lives. However, plastics wastes accumulating in the environment pose great danger to stability of ecological system. The use of plastics, therefore, has generated serious global concern due to their nonbiodegradability. Considerable effort has been devoted to develop biodegradable polymeric materials. Microorganisms have been. identified as potential biodegradative agents. In this proposed study, effects of Aspergillus niger inoculated at different times on the degradation of recycled low density polyethylene (rLOPE) . will be investigated. Dynamical mechanical analysis (OMA), creep, thermal degradation and biodegradability measurement will be conducted. OMA will be carried out in the '"reqll\.'lh\ range 0.3 to 30 HZ and temperature range from O°Cto 100"e. Creep measurements wiII he lilllh.' at 30°C, 50 °C and lOo°e. Time application will be 10 minutes and the recovery time wi II be 10 minutes. Diffusion measurements will be done by monitoring water uptake at room temperature by measuring mass difference at specific periods of time. Thermogravimetric Analysis (TGA) will be done using Lindberg Blue Tube Furnace from 25 °C to 700°C at heating rate of lOoC/minute. The models of analysis for DMA and creep data will be Vogel-Fulcher -Tammann (VFT) / William-Landel-Ferrry (WLF) and Arrhenius laws while in diffusion measurements Fick's second law of diffusion will be used.Item Impact of land-use activities on water quality of river Karoroha, Malewa catchment, Nyandarua county, Kenya(Kenyatta University, 2014-10-09) Oundo, Dickson DancanWater is the most important resource on the earth surface without which living organisms cannot survive. Human developments of any kind have a directlindirect impact on water quality and quantity. It should be an objective of every individual to ensure that water quality is maintained at all costs. This research examines the quantitative effects of land use activities on the water quality of River Karoroha in Malewa catchment in Nyandarua County, Kenya. The general obj ectrve of the study is to identify the impacts of land use activities on water quality of a river basin and model a relationship between land-use activities and the water quality. The research will employ an experimental research design to achieve this objective Water samples will be drawn from the river and water quality parameters will be measured both in situ and 111 a laboratory The water quality parameters are total suspended solids (TSS), total dissolved solids (TDS), temperature, pH, color, phosphorous, nitrogen, biological oxygen demand (BOD) and dissolved oxygen (DO). The obtained results will be compared to the set standards both by WRMA and WHO. Sampling and water collection will be done during both hydrological extremes between Sept-Dec so as to make a conclusive comparison The land use activities in the area will be identified by use of satellite images, observation and focus group discussions with the resource persons in the sub county The obtained results will be used to establish a relationship between land-use activities and water quality using ANOVA (analysis of variance) and regression analysis The results of t1115 research will be useful both to the country and the Nyandarua County The proposed research is vital in helping the government meet its vision 2030 especially under the social pillar flagship proj ects of rehabilitating and protecting the five water towers, inventory of illegal effluent discharge and water monitoring in cities and comprehensive mapping of land use patterns in Kenya The research will also help meet Nyandarua county strategic plan on water which is a key priority area for the county as it aims at investing in provision of clean water for domestic use as well as protecting the water catchment areas (Republic of Kenya 2013). This research is vital and has potential benefits to all stakeholders once undertaken.Item Plasma Adiponectin'hormone Levels in HIV and Tb Co-Infected Non-Injection Drug Users from Mombasa County, Kenya(Kenyatta University, 2014-10-09) Nebere, Saraphine NekesaHuman immunodeficiency virus (Hl'V) and tuberculosis (TB) co-infections are the main cause of increased morbidity and mortality in Kenya. Most of the antiretrovirals (ART) used in management of mY/AIDS are associated with dysregulation in adiponectin hormone levels. Low adiponectin levels are associated with insulin resistance, dyslipidemia and fat redistribution in HIV patients on combined ART. Altered levels of adiponectin are also associated with tuberculosis infection. Recently, the concentration of adiponectin in plasma has been used to assess severity of pulmonary TB in TB affected patients. Although there are profound metabolic alterations in HIV and TB co-infected patients, the levels of adiponectin as well as their association with clinical outcomes including among others, CD4 counts, mv -1 viral loads and BMI in HIV and TB co-infected patients has not been ascertained. This study, hence seeks to determine the levels of adiponectin, CD4 counts, viral loads and anthropometric measures in the following groups of non-injection drug users from Mombasa County: - HIV and TB co-infected patients, mv mono-infected patients, TB mono-infected patients and Healthy controls. HIV infected groups will further be divided into ART- naive and ART-exposed groups. Adiponectin levels will be measured using sandwich enzyme linked immunosorbent assay (ELISA) technique, CD4+ T-cell counts will be enumerated by the FACSCalibur machine while Hl'V-Iviral loads will be determined by real time polymerase chain reaction (PCR). SPSS Version 19.0 will be used to analyze the data obtained. Parametric data including adiponectin levels, CD4 counts, and anthropometric data will be summarized as medians and presented as box plots. Statistical comparisons across groups will be performed using non-parametric ANOVA tests followed by post-hoc Bonferroni correlation for multiple comparisons. Spearman's rank correlation tests will be used to determine the association between adiponectin levels and HIV-l disease outcomes. All tests will be two-tailed and an a-value of 5% (p<0.05) will be used for statistical inferences. This study will provide data on adiponectin levels in HIV and TB coinfected non-injection drug users from Mombasa County and their association with Hlv-I clinical outcomes. The results will also be important in the understanding of disease progression, staging and monitoring ART and TB treatment during HIV and TB co-infectionItem Identification and Functional Characterization of Striga Resistance Genes in Rice Ioryza Sativa L.)(Kenyatta University, 2014-10-09) Kuria, Eric KimaniRice, the second most important cereal crop globally, is mainly grown for food and is a staple food for more than half of the world's population. In sub-Saharan Africa, biotic stresses and lack of resources are major production constraints to farmers. An estimated yield loss of 16% attributed to weed infestation is recorded in the region with Striga spp. being the most prominent cause. Striga are members of the Orobanchaceae family with 89 genera containing 2061 species. However, Striga hermonthica (Del.) Benth. and Striga asiatica (L.) Kuntze are of the greatest economic importance in the region. Cultural control methods such as crop rotation, intercropping, different planting techniques, management of soil fertility and seed based technologies, have been tried against Striga with only modest gains. Striga resistance in crops has been attributed to differences in a few genetic regions within the genomes. Resistance or susceptibility to Striga in crops is influenced by genes. The growth regulating factors have been suspected to play a role during striga infection. This study attempts to identify and characterize Striga resistance genes in rice. Cloning of these genes, screening their function in transformed rice roots under laboratory conditions, stable rice transformations with putative resistance genes and assessment of the transgenic rice will be done. Agrobacterium rhizogenes will be used for induction of transformed hairy roots in composite plants carrying identified putative Striga resistance genes for analysis of Striga resistance in rice. Real time quantitative polymerase chain reaction will be used for analysis of expression of Striga resistance genes during infection with Striga hermonthica. Agrobacterium tumefaciens will be used for stable transformation of rice with putative Striga resistance genes and the resistance screened under laboratory conditions. For effective management of striga it is important to understand how it overcomes host defense mechanisms. This will be done through identification of effector genes whose products neutralize host defenses. Rice is an excellent model for genetic studies. Thus identification of Striga resistance genes will help in breeding and development of resistant rice as well as other crops such as maize and sorghum that are seriously affected by Striga in the sub Saharan Africa.Item Development and On-Host Evaluation of Controlled-Release Formulations of Optimised Potent Repellents or Blends against Rhipicephalus Appendiculatus(Kenyatta University, 2014-10-08) Kariuki, Margaret WangechiTick borne diseases are major constraints to livestock productivity and food security in many developing countries. They cause high morbidity and mortality in cattle, and prevent the introduction of highly productive but disease-susceptible breeds of cattle. They are also expensive to control and place a huge economic burden on poor small holder farmers. East Coast Fever (ECF, Theileria parva, Theiler 1904) is one of the most serious of the theileria species. ECF is transmitted primarily by the brown ear tick Rhipicephalus appendiculatus. In Africa, it is estimated that 1.1 million cattle suffer from ECF resulting to losses at US dollars 168 million. In Kenya, about 50-80% of the national cattle population of about 10 million animals is exposed to tick infestations and out of this 1% die of ECF each year. Use of semiochemicals represents a strategy for the control management of the vector which is eco-friendly. On host behavior studies of adult R. appendiculatus shows preference to feed mainly inside and around the ear of their host. Combination of a repellent blend from the anal region and an attractive blend at the ear has been shown to play natural "push" and "pull" roles, respectively, to guide these ticks to the cattle ears. In a preliminary study, application of a crude repellent blend collected from the anal region at the ears has been shown to confuse the ticks, most of which drop off the cattle. Preliminary work showed the presence of forty three compounds in the GC-MS of the anal odour. These compounds include ketones, phenols, amines and alcohols. The major constituents comprised of 4-methylguaiacol, 4-hydroxy-4-methl-2-pentanone, and 3-methyl-2-pentanone among others. Bioassays of blends of these and individual constituents showed varying levels of repellence, with 4-methylguaiacol showing the most repellent effect. A number of analogues of this constituent was tested and 2,4-dimethylphenol was found to be most repellent . The present research will build on these results, undertake further structure-activity studies and evaluate potent compounds individually and in blends in laboratory assays and on cattle. This will be followed by development of a controlled-release formulation of a selected repellent or blend, which can then be evaluated in a push tactic on the host animals. All data will be analyzed using Analysis of Variance (AN OVA) while the mean will be compared by Student -Newrnan-Keuls test at P 20.05.Item Genetic characterisation of solanum nigrum and related species using simple sequence repeats(Kenyatta University, 2014-10-08) Rwigi, Susan WagioSolanum nigrum (commonly referred to as black nightshade) and related species are world-wide weeds on arable land, gardens, rubbish pits, soil rich in nitrogen in moderately light and warm situation which occur from sea to montare levels. Human consumption of leaves and fruits as food is wide spread, particularly in Africa and South East Asia. Nightshades have also been used in the field of medicine in the manufacture of analgesics, ointments and vasodilators. In Kenya there are three distinct varieties of black nightshade, grown in high, medium and low altitude areas. Broad leafed nightshades are found throughout Africa. There are several wild species but the most popular species is Solanum scabrum. A wild variety Solanum villosum has also been identified in a number of regions in Kenya. Solanum nigrum and related varieties can be grown in wide range of soil types but do not tolerate drought. Yields range from 20-40 tons per hectare under good management. Many of the species are poisonous giving varying degree of toxicity which may be mildly irritable to causing fatalities with small quantities. In Kenya these species are found extensively around Mt Kenya, Mau forest, Kisii highlands and Kakamega. Farming is not extensive and only few farmers produce the crop. The limited information available on importance and basic aspects of this neglected and underutilized family, such as black nightshade, hinders the development of these species as well as their sustainable conservation. Exisisting knowledge on the genetic potential of these plants are limited and the information regarding the genomic organization of Solanum nigrum complex species found in Kenya is scarce. However molecular markers could help us gain a better understanding and the information could improve the genetic analysis to facilitate future breeding programmes. This work targets the use of SSR molecular markers in determining the genetic diversity of both cultivated and wild varieties of black nightshades in selected parts of Kenya. Leaf samples will be collected from five regions and morphological analysis done on leaf shape, colour of the fruits, nature of leaf surface and type of leaf margin. Samples will then be dried in snaptop bag containing silica gel in readiness for DNA extraction using the CTAB protocol. A set of7 SSR primers as used by Angeline van Biljon et ai, 2010 will be used for PCR amplification of the DNA. Final DNA concentration will be confirmed by electrophoresis in 2% agarose gel run at 120v for 40min in a TAE (tris acetate ethlydiquine tetra acetic acid) buffer and visualized with ethidium bromide staining under UY light. Bands in the SSR profiles of each individual plant will be scored as present or absent (lor 0, respectively) and subjected to sequential clustering algorithm using the Unweighted Pairgroup method with Arithmetic Means (UPGMA).The lengths will be analysed in an automated ABIR31 0 sequencer (Applied Biosystem) that use gene mapper TMsoftware. Morphological data will be subjected to analysis of variance (ANOY A) by the GLM procedure of the Statistical Analysis System and correlation coefficient to determine the degree of diversity. The relationships within populations of cultivated and wild types will be generated using phylogenetic analysis package GenAlex 6.3.and presented in a dendogram. Findings from this study will be useful in the improvement of wild black nightshade germplasm to develop suitable plants using Marker Assisted SelectionItem Effect of deposition temperature on the properties of al doped Sn02 in SnxSey-Sn02:AI P-N solar cell(Kenyatta University, 2014-10-08) Muchangi, Philip Mumbere M'buriNon- renewable sources of energy have been used for a long time making the natural resources such as fuels to become depleted. This has led to the increase in demand for energy to sustain the fast growing technological world. This has triggered the need for advanced but affordable and more efficient renewable sources based on solar cell technology to be applied. In respect to this, transparent conducting oxides and certain metal layers have been applied as front and back contacts on the solar cells. The optimal optical, electrical performance and structural strength of such devices is determined by the methods of deposition and the conditions under which the deposition is carried out. In this research thin films of Aluminium doped tin oxide and tin selenide at different concentrations will be deposited on a glass substrate by reactive evaporation and evaporation respectively using Edwards 306 AUTO Evaporation system. Different ratios of tin to selenium would be used to form tin selenide whose optical and electrical properties would be studied. The Tin oxide will be deposited at various doping concentrations in the range of 1% to 10% by mass so as to improve its conductivity. The electrical properties of both tin selenide and Al doped Tin oxide thin films will be studied using the four point probe set up and readings obtained by Keithley 2400 source meter. The optical properties in the range of 300nm-1200nm will be studied using the UV-VIS-NIR spectrophotometer. Results obtained will then be analysed by scout software to determine the optical constants of the films. The ratio of Aluminium doped Tin oxide that gives the best results will be deposited at different temperatures ranging from 400°c-600°c and then electrical and optical characterization of the films will be carried out. Finally SexSey-Sn02:Sn solar cell will be fabricated at the optimum deposition temperature using the optimum doping concentration. The performance of the p-n junction such as short circuit current (Isc), open circuit voltage (Voc), fill factor (FF) and conversion efficiency (0) will be studied using a solar cell simulator.