Thesis and Dissertation

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FACTORS INFLUENCING ENROLMENT AND RETENTION OF STUDENTS IN PHYSICS IN SECONDARY SCHOOLS IN IMENTI SOUTH SUB-COUNTY KENYA
(2016) KAIRO NKIROTE CATHERINE
Despite the place of physics in science, technology and national development, the number of students taking physics as their choice in secondary schools is declining. The purpose of this study was to investigate factors influencing enrolment and retention of students in physics classes in secondary schools in Imenti South Sub-County of Meru County. The study was based on achievement motivation theory. The study adopted descriptive survey research design. The target population was 14,097 subjects comprising of 13,943 students and 154 physics teachers in secondary schools in Imenti South Sub-County. Simple random sampling technique was adopted to select students and physics teachers from the population in Imenti south Sub-county. The sample size was 364 respondents comprising of 356 students and 8 physics teachers. Data was collected by use of three questionnaires, for the form two students, form three students and the other for the physics teachers. Piloting was carried out in two secondary schools in the neighbouring Imenti North Sub-county where 42 students and 4 physics teachers participated. Spearman Brown formulae was used to estimate the reliability co-efficient of the instruments. The reliability coefficient of 0.851 and 0.957 for students and teachers questionnaire respectively was obtained. The research instruments were validated with the help of supervisors. The data collected was cleaned, coded and entered into the computer for analysis. Statistical Package for Social Science version18 was used for data analysis. The data was analyzed using descriptive statistics and the findings presented using tables, graphs and charts. The study established factors influencing enrolment and retention in physics include; lack of adequate teaching and learning apparatus, poor performance in physics, teaching methods used in practical lessons, playing with electrical gadget and making models during early childhood, naming constants and principles after male scientists. The research findings will provide important information to policy makers and other stake holders in the Ministry of Education on the influence of available teaching and learning physics resources in schools in regard to enrolment and choice of physics. The study will provide information to physics teachers on the influence of the methodologies used in teaching physics on selection of physics by the students. This may help physics teachers to know which intervention measures to take while teaching in order to improve student’s enrolment in physics. The study is of significance to the students because it enlightens them on the importance and the benefits of studying physics. The study also will sensitize the parents on the importance of physics and their role in exposing children to experiences that demonstrate physics knowledge during childhood. This will help in improving enrolment and retention of students in physics in secondary schools.
MODELING THE EFFECTS OF INTERFERENCE IN FERTILITY RATE: A CASE STUDY OF RWANDA, INDONESIA AND KENYA
(2016) ODERO EVERLYNE AKOTH
Many studies have been done on fertility for many years. However, very little has been documented in the existing literature concerning modeling of fertility in the presence of interference, yet interference to fertility is a common phenomenon. In this study fertility data sets for Rwanda, Indonesia and Kenya were modeled before and after interference. The parameters of the model were estimated ted by the maximum likelihood estimation method. The model life table approach was used to determine the Net Fertility Value, Fo. A relationship between fertility rate in the presence of interference and population growth was also determined Using Akaiko's Information Criteria (AIC) population growth was also determined. Using Akaike's Information Criteria, (AIC), it was established that amongst the distributions fitted; Gamma, Weibull and Lognormal, was established that amongst the distributions fitted: Gamma. Weibull and Lognormal Gamma gave the best fit for the fertility rate data, for all the countries studied, and interference simply shifts the Gamma distribution parameters. The result of this study would help the Governments to understand fully the effect of interference on fertility rate and plan for it. Demographers would also benefit from this study since it can be used to project population growth after an interference.
SEROPROFILE, GENETIC DIVERSITY AND DRUG RESISTANCE OF HEPATITIS B VIRUS AMONG INFECTED INDIVIDUAL ATTAENDING MAMA LUCY KIBAKI
(2016) SEPHA NYATICHI MABEYA
Human immune deficiency virus (HIV) and Hepatitis B virus(HBV) coinfection is highly prevalent among high risk populations including pregnant women and infants. This poses a global public health challenge in laboratory diagnosis and is a major consideration for anti-HIV treatment. These viruses share common modes of transmission that is; through blood and body fluids. Further, there is little information on sero-profiles and circulating HBV genotypes in Kenya. This study aimed at determining seroprofiles, genetic diversity and drug resistance of HBV among HIV infected individuals attending comprehensive care clinic of Mama Lucy Kibaki Hospital Nairobi, Kenya. Ethical approval was sought from Kenyatta university ethics review committee and a cross-sectional study was conducted whereby the participants/guardians who gave consent/assent were included into the study. Their demographic data was collected using a questionnaire and 5ml of blood was collected from each participant using systematic sampling technique. The HBV seroprofiles were determined using the HBV-5 panel rapid diagnostic cassette according to the manufacturer’s instructions (Healthaw Medical limited, Hangzhou, China) . Viral DNA was extracted using Qiagen® Miniviral DNA isolation kit and the HBV-pol gene amplified by nested PCR. The amplified products were sequenced using the Big Dye® sequence terminator kit (Applied Biosystem®) on an automated ABI 310 sequencer (Applied Biosystem, Foster City CA). The generated sequences of HBV were analysed for drug resistance and genetic diversity determined using Molecular Evolutionary Genetics Analysis (MEGA5). Four hundred participants were recruited and 293 were females, 107 were males with their age ranging between 4 months and 73 years. Of the 400 sera; (111) 27.8% were HBV immunized, 19 (4.8%) were recovery cases, 12 (3%) had acute disease, 10 (2.5%) were chronic, 9 (2.3%) had occult HBV and 7 (1.8%) asymptomatic. The prevalence of HBV/HIV was found to be 7.25% based on the presence of surface antigen. After the confirmation of HBV DNA by gel electrophoresis, 13 samples were successfully amplified, purified and sequenced. All the 13 sequences were confirmed as HBV genotype A. Nucleotide drug resistance mutations were found in six (6) participants’ samples. These were rtV173L, rtL180M, rtM204V which are major mutations associated with lamivudine, telbivudine and emtricitabine resistance. This study indicates that the utility of HBV seromarkers and infection staging are important in disease diagnosis. The findings confirm that, HBV genotype A remains the most predominant genotype circulating in Nairobi.This study proposes a need for a continuous surveillance of HBV genotype trends and evolution of drug resistance because the current findings have major implications on treatment of HBV in Kenya
Extraction and Characterization of Gelatin from Lates niloticus Scales and Potential Industrial Applications
(2016-07-31) CHEBON SAMMY KIPLAGAT
This study sought to extract and characterize gelatin from Lates niloticus (Nile perch) scales, then blend it with polyvinyl alcohol (PVA). Hydrolysis of the scales was done using a crude alkaline protease harvested from a bacterium, Bacillus cereus strain wwcp 1, obtained from Lake Bogoria and the resulting solution lyophilized to obtain gelatin powder. The yield was calculated based on the dry weight of the scales and was shown to be 16.3%. The sample was characterized using infrared spectroscopy and showed peaks at 3442 cm-1, 1653 cm-1 and ~ 1590 cm-1 corresponding to Amide A, Amide I and Amide II bands respectively. Amino acid analysis of the sample was done using an Agilent 1260 HPLC. Glycine was the most abundant amino acid (21.7%), followed by proline (14.6%) and alanine (11.8%). Isoleucine, Histidine and Tyrosine were the least abundant (1.8, 1.4 and 0.9% respectively). Polyvinyl alcohol-gelatin blend films of various compositions ranging from 10% to 90% PVA were prepared by solution casting method, Differential Scanning Calorimetry (DSC) and Thermo-gravimetric Analysis (TGA) tests showed the films had glass transition, melting and thermal decomposition onset temperatures intermediate between those of the respective individual polymers ( PVA and gelatin). The thermal stability of the films reduced with the increase in the amount of the less thermally stable constituent. Lastly, potential applications of the prepared blend films were investigated. Batch experiments to assess the potential of the polymer blend films as adsorbent material were done using Methylene Blue dye. The films were found to adsorb up to 64% of the dye. The percent dye removal varied with initial concentration of the dye and contact time
AN ASSESSMENT OF THE RELATIONSHIP BETWEEN HEAD TEACHERS’ LEADERSHIP STYLES AND PUPILS’ ACADEMIC PERFORMANCE IN PUBLIC PRIMARY SCHOOLS IN MALINDI SUB-COUNTY, KENYA
(2016-11) FREDER MWALUNGO KATUNDA
This study aimed at investigating the relationship between head teachers’ leadership styles on pupils’ academic performance in public primary schools in Malindi Sub County, Kenya. More often than not, head teachers find themselves on the receiving end of poor performance in public primary schools. Most parents tend to attribute poor performance of their children to head teacher’s leadership styles. The objectives of the study were to: find out the relationship between democratic leadership style and pupils’ academic performance; determine relationship between the autocratic leadership style and pupils’ academic performance; find out the relationship between the transformative leadership styles and pupils’ academic performance; and determine the leadership the relationship between the transactional leadership styles and pupils’ academic performance. This study was based on Fiedler’s contingency theory and rationale theory of performance. quantitative methods were used in this study. The study adopted the correlational research design that sought to measure the relationship between the variables. The study targeted a population of 750 teachers and head teachers from 30 public primary schools in Malindi Sub County. The sample was 200 participants consisting of 192 teachers and 8 head teachers. The sample was obtained through stratified sampling to establish the number of head teachers and teachers to include in the study sample. Simple random sampling was used to select 8 head teachers from 30 schools and 192 teachers from 720 teachers. Questionnaires were used; one for teachers and another for head teachers to collect data. Pilot study was carried out in two neighbouring schools which were not included in the study. The validity of the instruments was ascertained by the supervisor and two other lecturers who gave verdict on their appropriateness. The reliability was verified by using the test retest method whereby Pearson Product Moment correlation was 0.75. To cover ethical issues, clearance was done with Mount Kenya University and a permit was obtained from NACOSTI and official letters from the County Director of Education and the District Education Officer. The participants signed informed consent forms and were assured of their privacy and confidentiality. The data was analyzed quantitatively using both descriptive and inferential statistics. The findings established that independent variables had positive and significant relationship with pupils’ academic performance since the estimated Pearson Linear correlation coefficient statistic was significant at the 99% level for all the variables (Sig.<.01, r>.9). All the null hypotheses filed to be accepted. The study concludes that from the three tests on a hypothesis that is correlation, regression and coefficient, all indicates rejection of the null hypothesis paving a way for alternative hypothesis. The study recommends that head teachers ought to be given refresher courses on appropriate leadership styles to be applied in their institutions. The ministry of education should allow teachers to teach in one school for at most 10 years so as to gain experience before transferring to another school. Quality assurance officers needed to be visiting schools regularly to establish level of performance and offer necessary intervention where things are not in order. The study findings are expected to provide useful information to head teachers in helping them to re-examine and appraise their own leadership styles and hence make adjustment where necessary.
EFFECTIVENESS OF DIFFERENTIATED INSTRUCTION IN ENHANCING STUDENTS’ ACADEMIC ACHIEVEMENTS, SELF-CONCEPT OF ABILITY AND MOTIVATION TOWARDS LEARNING OF CHEMISTRY IN SECONDARY SCHOOLS IN MAARA SUB-COUNTY, KENYA
(2016-11) ROSE GATUNE MUGWIRIA
Students perform poorly in Kenya Certificates of Secondary Education Chemistry examinations in Kenya. Chemistry is important for understanding composition, properties and behavior changes of matter that form the environment. The teaching of Chemistry aims at developing scientific attitudes, concept, principles and skills in learners. Differentiating instruction means tailoring instruction to meet individual needs of learners. Differentiating instruction consists of efforts of teachers to respond to the variance among learners in the classroom. This study investigated the effectiveness of differentiated instruction in enhancing students‟ academic achievements, self-concept of ability and motivation towards learning of chemistry. The study was guided by Howard Gadner Theory of multiple Intelligence. Quasi experimental research design was employed and in particular Solomon‟s four group design was used. The research was carried out in Four Day co-educational secondary schools in Maara sub-county, Kenya. The target population was 12,187 chemistry students. The accessible population was 1,242 form two chemistry students in Day co educational secondary schools. A purposive sampling technique was used to draw the participating schools. Simple random sampling was used to select and to assign participating schools in Experimental and Control groups. The sample size was 165 form two chemistry students. The research instruments used were Chemistry Achievement Test, Students‟ Self Concept of Ability Questionnaire and Students‟ Motivation Questionnaire. The instruments were piloted to determine their reliability, while validity of the instrument was ascertained by experts‟ opinions from Department of Education and Resource Development of Chuka University. Reliability coefficient for CAT, SSCAQ and SMQ was 0.74, 0.80 and 0.77 respectively. The experimental groups (E1 and E2) were taught using differentiated instruction teaching approach while the control groups (C1 and C2) were taught through conventional teaching approach. Statistical Package for Social Sciences (SPSS) version 21 was used for data analysis. The raw data obtained was analyzed using descriptive statistics (Mean, Standard deviation, percentages) and inferential statistics (One-way ANOVA, ANCOVA and t-test). The level of significance for acceptance or rejection of null hypotheses was at α = 0.05. The findings of the study indicated that differentiated instruction significantly improved the students‟ achievement, self concept of ability and motivation towards learning chemistry. It was also found out that when students were taught using differentiated instruction, gender did not affect their achievement in chemistry. The findings are expected to form a frame of reference for further research on innovative teaching strategies in chemistry education as well as in science education in general.
CHILD EXPOSURE TO LEAD IN THE VICINITIES OF INFORMAL USED LEAD-ACID BATTERY RECYCLING OPERATIONS IN SLUMS, KENYA
(2016-11) MAUREEN AUMA ONDAYO
Leadexposure frominformal used lead-acidbattery (ULAB) recyclingoperations is a seriousenvironmental healthconcern. Researchshows that youngchildrenliving inthe vicinitiesoftheseoperationshaveelevatedbloodleadlevelsandfatalitieshavealsobeen reported. FromJanuary2015 toAugust 2015, thestudy investigatedchildexposure to lead inthevicinitiesof informalULABrecyclingoperations inNairobi slums,Kenya. This was in consideration of activity patterns of children under seven years that influencedexposurelevelsthroughhousedustandsoil.Topsoil (N=232)andfloordust (N=322)sampleswerecollectedfromdwellingunits(N=120)andpreparatoryschools (N:44)andanalyzedusing inductivelycoupledplasma-optical emissionspectrometer (ICP-OES) at theMines aridGeological Department Laboratory in theMinistryof Mining,Nairobi.Fromthe lead levels insoil andhousedustobtained,childblood lead levelswere subsequently predictedusing the IntegratedExposureUptakeBiokinetic Model forLead inChildren(IEUBK),Windowsversion.Results indicatedhigh indoor andoutdoor lead contamination instudied areas. Lead loadings inall the floor dust samples (100%) fromDandota, Kariobangi andMukuruslums exceeded theUSEPA guidancevaluefor leadonfloorswitharangeof65.2-58,l94ug/ft2.Control floordust samples recorded lower lead loadingsas compared to thevalues recorded inDandora, Kariobangi andMukuruslums. 70.7%ofthesoil samplescollectedfromwastedumps, industrial sites, residential areas, playgrounds and preparatory schools in Dandora, Kariobangi andMukururecorded leadconcentrations that exceeded the respectiveUS EPAguidancevalues for lead insoils. Leadconcentration inall (100%of) thecontrol soil sampleswerebelowtherespectiveUSEPAguidancevalues. Fromthe IEUBKwin predictions,nearly99.9%ofchildren<7yearsoldlivingnear informalULABrecycling operations inDandora, Kariobangi andMukuru slums, were at riskof being lead poisonedwithpredictedbloodleadlevelsabovetheCDCreferencevalueforbloodlead. 99.9%ofexposedchildrenlivinginDandora,KariobangiandMukumslumsarelikelyto havebloodlead levelsabove20kg/dL, 19kg/dLand34kg/dLrespectively.Thestudy establishedthatDandora,Kariobangi andMukuruslums facevastenvironmentalhealth challenges,withmanychildrenat riskofleadpoisoningduetotherapidunprecedented growthof informalULABrecycling. Thesoil andhousedust results demonstrate the need for coordinatedefforts towards decreasing leademissions frominformal battery recycling inNairobi slumsand to remediateexisting soilsparticularlyaroundbattery workplaces and dumpsites. Childblood lead levels should be clinically tested and appropriateinterventionmeasurestaken.
USE OF FISH BIOMARKERS TO ASSESS MICRO- POLLUTANT EXPOSURE AND EFFECTS IN LAKE KANYABOLI, KENYA
(2016-11) CORNEL AKWIR OMONDI
A lot of research in ecotoxicology is currently focused on identifying and developing suitable biomarkers for use in assessing environmental pollution. This study, set out to evaluate the use of a suite of biomarkers in Clarias gariepinus in assessing micropollutant exposure and effects in Lake Kanyaboli from November 2013 to April 2014. Fish were collected with the aid of a gill net of mesh size 4” and 5” whereas bottom sediment was collected by ErkMan crab sampler. The concentrations of Cadmium, Chromium, Zinc, Copper, and Lead in lake sediment and in the liver of Clarias gariepinus were determined using Flame Atomic Absorption Spectrophotometry (AAS). A necropsy-based health assessment index (HAI), the condition factor, hepatosomatic index (HSI), and splenosomatic index (SSI) were measured in fish from all the sampling stations. Fish were semi-quantitatively sampled from which an organ index was calculated to examine the micro- pollutant exposure and effects in fish from all the study stations. Metals concentrations were significantly (Fα, v1, v2 = 7.16; p < 0.05) higher in station 2 than at the other stations. The mean heavy metal concentration in Clarias gariepinus liver were Cd (nd-0.22±0.01), Cr (0.37 ± 0.01 - 1.67 ± 0.03), Zn (7.12 ± 0.03 - 13.40 ± 0.32), Cu (2.12 ± 0.12 - 4.16 ± 0.12) and Pb (1.63 ± 0.33 - 14.40 ± 0.58). Zn exhibited a significance difference between the stations (Fα, v1, v2 = 7.79; p < 0.05). Redundancy ordination analysis (RDA) revealed positive linear relation between heavy metals in sediments and fish liver except for Zinc concentration in sediments and fish liver which showed a negative relationship. The mean of the biomarkers were HAI (20.61 ± 1.01 - 47.43 ± 1.12), Condition factor (0.60 ± 0.03 - 0.91 ± 0.29), HSI (0.53 ± 0.03 - 0.67 ± 0.03), SSI (0.08 ± 0.00 - 0.12 ± 0.01) and Semi-quantitative histological assessment index (8.3 ± 0.41 - 17.63 ± 0.36). The multivariate analysis of the histology – based fish health assessment index (HBFHAI) showed that these biomarkers are being influenced by the concentration of heavy metals in sediments as well as fish liver and therefore qualified as biomarkers for assessing pollutant exposure and effects. It is concluded that histology-based fish health assessment index biomarkers can be used to assess the health of aquatic organisms and ecological health of Lake Kanyaboli and other aquatic habitats within the Lake Victoria Basin. However, a more comprehensive chemical analysis of water and sediments samples including the measurements of endocrine disrupting chemicals is recommended for future studies to further investigate possible causative agents regarding liver alterations identified.
FACTORS INFLUENCING ADHERENCE TO ANTIRETROVIRAL THERAPY IN EMBU TEACHING AND REFERRAL HOSPITAL, EMBU COUNTY, KENYA
(2017-03) EVANGELINE KANANU NJUE MUGOH
Adherence to antiretroviral therapy is a major predictor of the survival of individuals living with HIV/AIDS. Appropriate use of antiretrovirals (ARV’s) has improved the health of many human immunodeficiency virus (HIV) positive individuals. The effectiveness of HIV treatment depends on sustenance of high levels of adherence to ARV; however, ARV regimens are often complicated and can be affected by varying dosing schedules, failing to have proper dietary requirements and patients developing adverse effects. The main objective of this study was to determine factors influencing adherence to Anti-retroviral drugs among HIV and AIDS patients 18 years and above in Embu Teaching and Referral Hospital comprehensive care clinic. A cross sectional study was carried out at EmbuTeaching and Referral Hospital in EmbuCounty, Kenya. Stratified random sampling was used to obtain relative proportion of male and female adult respondents in the sample population. Three hundred and thirty one HIV positive patients were chosen from a total of 1694 patients who were active in ART for more than one year. A semi-structured interview schedules was used to obtain demographic information and patients view on various dimension or ART services at the facility. The study revealed thatalmost half (48.2%) of the respondents had optimal adherence to ART treatment while 51.8% had sub-optimal adherence to ART treatment. Over a third (34.9%) of the patients indicated that travelling was the main cause of hindrance to optimal adherence to treatment. Other reasons included forgetfulness 23.5%, tiredness of taking drugs all the time 20.8% and side effects 20.8%. Patients aged below 25 years were more likely to have optimal ART adherence as compared to respondents aged 56 years and above (ᵡ 2 =10.745, df=4, pvalue = .030). Monogamously married and polygamous married patients more likely to have optimal adherence as compared to widowed or widower respondents (ᵡ 2 =17.944, df=4, p-value = .001). Majority (88.0%) of the respondents had disclosed their HIV status to other people of whom 46.9% had disclosed to their spouse/sexual partner and 49.7% of them had been accorded moral support. There was significant association between adherence to ART and the type of drug respondent was using with AZT, ddl, NFV having the highest proportion of sub-optimal adherence to treatment while respondents on D4T, 3TC, NVP had the lowest proportion of suboptimal adherence to treatment. Patients who had sub-optimal ART adherence significantly had longer waiting time and deemed costs of co-infection treatment to be higher as compared to respondents who had optimal ART adherence. Convenience of the facilities for people with chronic ailments and waiting time at the facilities were reported to be lower. The study concludes that majoritypatients had sub-optimal adherence to ART treatment. Adherence was significantly influenced by age; marital status; engagement in income generating activity;type of drug takenand costof coinfection treatment;health facility accessibility and perceived waiting time.The study recommends that HIV patients should be sensitized on importance of carrying ART drugs when travelling and the use of treatment assistants to ensure optimal adherence thus enabling them fully realize its life extending benefits as it has been shown that there is significant non-adherence among HIV positive patients on ART in the County.
SCREENING, ISOLATION AND CHARACTERIZATION OF HYDROCARBONOCLASTIC BACTERIA FROM OIL CONTAMINATED SOILS
(2017-05) Mwaura N. Agnes
Petroleum and its products continue to serve as a principle source of energy for industries and daily life. However, their release into the environment is a worldwide concern since some products are acutely toxic or possess mutagenic, teratogenic and carcinogenic properties. Several oil disposal methods have been applied over time with bioremediation emerging as the most promising technology. It takes advantage of the versatility of soil microbes to degrade hydrocarbon contaminants. Unlike conventional disposal methods, bioremediation is an environmentally friendly and cost effective method that simulates natural processes for complete degradation of hydrocarbons into innocuous compounds. This study focused on isolation, morphological and biochemical characterization as well as molecular identification of bacteria possessing hydrocarbon-degrading properties. The study also aimed at optimizing appropriate culture conditions for the isolates as well as screening for alkane hydroxylase enzyme. Isolation of hydrocarbon degrading microbes from soils polluted with used motor oil around Ngara, Nairobi-Kenya was carried out using Bushnell Haas media supplemented with used engine oil. The isolates were screened for ability to utilize heating oil, hexane, octane, toluene and diesel oil hydrocarbons. Characterization of the isolates was carried out by performing Gram’s iodine and potassium hydroxide as well as starch, catalase and carbohydrate fermentation tests. The isolates were also identified through PCR amplification and sequencing of 16S rDNA gene and comparison of obtained sequences with those retrieved from Genbank database. Optimization of culture conditions of three efficient degraders was performed using diesel oil and cellular growth monitored through biomass determination. Hydrocarbon analysis was performed using GC-MS following culturing in diesel oil. Alkane hydroxylase (alkB) gene was amplified using alk-3F and alk-3R primer pair. Among 21 microbes isolated, nine were selected based on their ability to utilize the hydrocarbons and characterized. The isolates were observed to mineralize heating oil, hexane, octane and toluene as well as diesel oil. PCR amplification of 16S rDNA gene revealed that the nine isolates belong to six different genera; Pseudomonas, Acinetobacter, Klebsiella, Enterobacter, Salmonella and Ochrobactrum. Based on their ability to degrade the hydrocarbons, three isolates were selected and their growth conditions optimized. Optimum degradation of diesel oil was recorded at <1 % substrate concentration, pH 7, temperature of 37 0C and using yeast extract as a nitrogen source. GC-MS analysis of diesel oil degradation demonstrated that the isolates were capable of readily degrading linear, branched, cyclic and isoprenoid alkanes as well as aromatic hydrocarbons with fatty acids, aldehydes and alcohols produced as intermediate metabolites. Isolate 1C was identified as the most efficient hydrocarbon degrader based on utilization of the different hydrocarbons tested. Its alkane hydroxylase gene was successfully amplified indicating the isolate’s potential catabolic capability in degrading alkanes. Overall, the characterized bacterial isolates may constitute potential candidates for biotechnological application in environmental cleanup of petroleum contaminants
EVALUATION OF PERFORMANCE APPRAISAL TOOL ON EMPLOYEE PERFORMANCE IN KENYA COMMERCIAL BANK, NAIROBI COUNTY
(2017-06) LEAH NJERI NYAMU
Performance appraisals improve the work performance of employees by helping them realize their full potentials in carrying out their firm's mission and also, to provide information to employees and managers for use in making work-related decisions. They provide feedback to employees; determine training and development needs, numbers to be promoted as well as the levels of motivation. Performance appraisals, however, are beset with difficulties as a result of their complex nature. The general objective of the study therefore, was to evaluate the performance appraisal tool on employees‟ performance in Kenya Commercial Bank. The research design used in the study was descriptive research design because it was appropriate for the achievement of the research objectives. The population for the study was 355 and a sample size of 107 was selected using cluster sampling method to group the target population according job titles. The study applied purposive sampling to select Nairobi County because of easy of accessibility. Questionnaires were used as instruments for the study and 107 questionnaires were distributed to the members of staff and subordinate as the respondents. The data was analyzed using descriptive analysis. Organized data was interpreted on account of concurrence and standard deviation to objectives using a computer package SPSS version 21. The researcher in addition used correlation analysis and a multiple regression analysis to determine the relationship between dependent and independent variables and their level of significance. The research was based on Attribution Theory, Implicit Theory, Equity Theory and Expectancy Theory. The information obtained from this study provided commercial bank Human Resource Managers and decision makers with better insights into employee performance appraisal programs that could be used to improve employee performance.
ASSESSMENT OF THE PHARMACEUTICAL MANUFACTURING INDUSTRY IN KENYA TO FORECAST LOCAL PRODUCTION SUFFICIENCY
(2017-10) SARAH KADESA VUGIGI
The World Health Organization’s global strategy on public health aims to support Member States to improve access to essential medicines. The desire of Kenya Government to implement this is expressed by formulation of Kenya National Pharmaceutical Policy (2010) which encourages local production of essential medicines for self-sufficiency. The pharmaceutical manufacturing industry in Kenya is engaged in production of various types of dosage forms but its capacity and capability to produce essential medicines for Kenyans have not been determined. The aim of this study was to assess the pharmaceutical manufacturing industry in Kenya to forecast local production sufficiency. This was attained by evaluating the manufacturing capability, production capacities and compliance with international marketing authorization standard of the Kenyan pharmaceutical industry. The 24 licensed manufacturers of medicines for human use were assessed. Data was collected on the current drug situation in Kenya by scanning Pharmacy and Poisons Board database to determine range of products that are registered in Kenya. Local pharmaceutical manufacturer’s product lists, Kenya Essential Medicines list and pharmaceutical tender lists of three major procurers in Kenya (Kenya Medical Supplies Authority, Kenyatta National Hospital and Mission for Essential Drugs and Supplies) were examined to establish the proportion of products which was manufactured locally. Prices competitiveness and market share of local products were evaluated and subsequently, pharmaceutical equivalents of 150 locally manufactured essential medicines were determined. Data on production capacity for 5 years (2010-2014) and compliance of facilities with good manufacturing practices standard and other prerequisites of marketing authorization was obtained using a structured questionnaire. Results showed that solid dosage forms were majority (54.9 %) of local products and sterile preparations were minority (2.7 %). Locally manufactured products accounted for 14.5 % of registered and 21.5 % of retained products. Local firms manufactured 38.4 % of products listed as essential medicines and 55.6 %, 24.5 % and 21.8 %, respectively, of pharmaceutical products procured by Kenya Medical Supplies Authority, Kenyatta National Hospital and Mission for Essential Drugs and Supplies. The overall percentage of local pharmaceutical equivalents was 32.5 % for registered products. There was no variation between mean prices of local and imported pharmaceutical equivalents. Scatter diagrams demonstrated that imported pharmaceutical products comprised both low and highly priced brands. The overall utilized production capacity (two shifts) was 21.5 %; tablets (24.1 %), capsules (12.8 %), liquids (25.3 %), dry syrups (21.8 %), external preparations (21.3 %) and oral rehydration salts (23.6 %). This study projected the year for self-sufficiency in non-sterile medicines produced in the local industry as 2043. Good manufacturing practices standard was satisfactory at 11 facilities while the rest were striving to achieve compliance. Research and development of new products was limited in most facilities with 1 % of the workforce deployed in this department. It is concluded from this study that Kenya depends heavily on imported drugs for her essential medicines needs. Majority of local products were less competitive than imported products and production capacity was underutilized. Majority of manufacturers adhered to current good manufacturing practice standards but were inadequate in research. This study recommends augmentation of research and development by the local pharmaceutical industry to generate new products. In addition, substantial government support is required to propel the industry to improve product range, product competitiveness and production capacity utilization.
PREVALENCE OF ECHINOCOCCOSIS IN DOGS, CATTLE, SHEEP AND GOATS, LEVEL OF KNOWLEDGE AND ASSOCIATED ECONOMIC LOSSES
(2018) MABEL INYANGALA GACHENGO
Cystic Echinococcosis (CE) is an emerging and re-emerging zoonotic infection caused by the larval stage of the dog tapeworm of the genus Echinococcus. It causes great public health and economic problems and remains neglected in Sub-Saharan Africa. The level of knowledge is poor in most developing countries. This study was carried out to determine the prevalence of echinococcosis and its trend, level of knowledge and associated economic losses in Laikipia West Sub-County. A total of 4969 animals (522 cattle, 3428 sheep and 1019 goats) slaughtered in abattoirs were inspected for hydatid cysts; a questionnaire was administered to one adult member from each of the 300 household using mobile data collection Kit. Faecal samples from 401dogs were used to determine prevalence of echinococcosis in dogs. Data from Veterinary office meat inspection reports 2010-2014 were used to determine trends and associated economic losses due to CE. The prevalence of CE in slaughtered animals was 8.8% in cattle, 1.7% in sheep and 1.7% in goats. Prevalence of echinococcosis in dogs was 0.5% (2/401). The level of knowledge of echinococcosis was 25% (n=300). A total of 98,495 animals were inspected during the period 2010-2014 and results showed an increasing trend with time for both prevalence and economic loss. There was evidence of CE transmission and the level of knowledge of Echinococcosis was low. The public health implications and economic losses call for concerted control efforts. More elaborate studies on echinococcosis are recommended in dogs and man.
Potential use of Kenyan Entomopathogenic Nematodes and Neem (Azadirachta indica) for the Sustainable Management of Tomato Leaf Miner (Tuta absoluta)
(2018-06) DAVID MUNYUA MUTEGI
The tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) was reported in Kenya in 2014 and has become a devastating pest of tomato crop in both the field and in the greenhouse. The objectives of this study were; to determine the pathogenicity of Heterorhabdities species and Steinernema karii nematodes against tomato leaf miner in laboratory conditions; to evaluate the insecticidal effects of neem biopesticide against tomato leaf miner in the greenhouse and to evaluate the effectiveness of entomopathogenic nematodes and neem combined with entomopathogenic nematodes as management options for tomato leaf miner in the greenhouse conditions. Entomopathogenic nematodes (EPNs) used in the study were obtained from Kenya Agricultural and Livestock Research Organization (KALRO) entomopathogenic nematodes laboratories and Tuta absoluta larvae were obtained from a colony reared and maintained in a greenhouse at Kabete Campus Field Station, Nairobi. Multiplication of the EPNs was done by invivo method or the insect-bait technique with the third instar of greater wax moth (Galleria mellonella). Bioassays were conducted in petri dishes where the effects of EPNs concentrations; at 100, 300and 500Ijs/ml on Tuta absoluta larvae exposed for 24-72 hours were evaluated. Secondly, three different concentrations namely; 20ml/20L, 40ml/20L and 60ml/20L of Nimbecidine® (Azadirachtin) were evaluated against Tuta absoluta populations in the greenhouse. Thirdly, the following management options; Steinernema karii nematodes alone applied at a rate of 1000 Ijs/ml with oil adjuvant Addit® as a wetting agent in water, Steinernema karii nematodes and neem (Azadirachtin 0.03%) applied sequentially after one hour at a rate of 40ml/20L were evaluated against Tuta absoluta populations. These were compared with Coragen® SC (20% Chlorantraniliprole) synthetic pesticide applied at the rate of 3ml/20L and control where only water was applied. A delta sticky trap supplied with Tuta absoluta pheromone was hanged at the centre xiii of the greenhouse at a height of one metre for monitoring Tuta absoluta numbers to enable the initiation of treatments. The results obtained showed that, the evaluated concentration rates of Heterorhabditis species and Steinernema karii at 100Ijs/ml, 300 Ijs/ml and 500 Ijs/ml significantly caused (p < 0.05) mortality to the Tuta absoluta larvae and the highest mortality was recorded at 500 Ijs/ml concentrations with an exposure period of 72 hours. Steinernema karii was more pathogenic compared to Heterorhabditis species with respect to exposure time, having shown 100% and 91.5% larval mortality, respectively. Secondly, the evaluated neem concentrations 20ml/20L, 40ml/20L and 60ml/20L significantly (p < 0.05) reduced Tuta absoluta population in the greenhouse tomato. The high concentration (60ml/20L) was more effective in reducing Tuta absoluta population and fruit damage compared to the lower concentrations and control. High fruit damage of 96.2% was recorded in the control compared to 30.0%, 23.4% and 20.0% for 20ml/20L, 40ml/20L and 60ml/20L dose rates, respectively. Lastly, EPNs alone and EPNs combined with neem significantly (p < 0.05) reduced the population of Tuta absoluta. The number reduction of Tuta absolutaby EPNs combined with neem did not differ with that which was achieved in Coragen®. Tomato fruit damage was highest in the control with 91.5% compared to 10.8%, 7.9% and 3.0% for EPNs alone, EPNs combined with neem and Coragen®, respectively. This study demonstrates the potential of EPNs alone or in combination with neem applied successively at a one hour interval, as an alternative strategy for the sustainable management of Tuta absoluta in the greenhouse conditions.
FUNCTIONALIZED GEOPOLYMERS DERIVED FROM CLAY AND RICE HUSK FOR REMOVAL OF SELECTED HEAVY METALS AND METHYLENE BLUE FROM AQUEOUS SOLUTION
(2018-10) MAINGI MUKORA FRANCIS
With the onset of industrialization, humanity has witnessed various ecological issues in the society and disturbance of ecosystem. Heavy metals and methylene blue are very toxic substances known to cause detrimental effects to human health when ingested even at low concentrations. Several techniques are available for removal of heavy metals, and dyes from the wastewater such as chemical precipitation, ion exchange, adsorption, membrane among others. Among these technologies adsorption is preferable for wastewater treatment due to its simplicity in design, high efficiency and availability of materials involved. Geopolymers are inorganic polymers and have been in use in construction industries as alternatives to ordinary portland cement but very little information is available on their use in environmental pollution management. This study aimed at synthesizing and functionalizing amorphous geopolymers from common clay and rice husk ash for use as adsorbents in removal of heavy metal ions and methylene blue from contaminated water. There is adequate literature indicating that clay minerals contain both silicates and alumina while rice husk ash contains substantial amounts of silica. This work therefore reports synthesis of geopolymers GP 1, GP-2 and GP-3 using clays and rice husk ash that were functionalized using citric acid and EDTA for use in adsorption of heavy metals and colour. Characterization of the geopolymers was done using FT-IR, EDS, XRD and SEM. Batch experiments using Pb (II), Cd (II), Zn (II) ions and methylene blue (MB) were done. FT-IR indicated presence of Al-O and Si-O bonds which are the finger prints of geopolymers. XRD analysis showed presence of amorphous phase between 18-36° (2θ) an indication that geopolymerization occurred. SEM analysis revealed the formation of a heterogeneous matrix which consists of a dense continuous gel with microcracks and voids on geopolymer adsorbents. The mean percentage uptakes of 99.32 ± 0.04, 99.74 ± 0.01, 91.33 ± 0.06 and 91.99 ± 0.57 of Pb (II), Cd (II), Zn (II) and MB were achieved respectively. Various equilibrium models were employed and from the correlation coefficients (R2 > 0.94), the data was found to fit best in Langmuir Freundlich model (Sips). The highest adsorption capacities of Pb (II), Cd (II), Zn (II) and MB were 326.5, 175.5, 169.9 and 20.74 mg/g respectively, attained using GP-3E. Increased adsorption of Pb (II), Cd (II), Zn (II) ions and MB was observed upon functionalization as well as when Si/Al ratio increased. Kinetic studies showed that a pseudo- second order model was more suitable than the first order in explaining the adsorption mechanism. This indicated that the adsorption transient behaviour used valence forces or exchangeable electrons and that chemisorption was more pronounced in the rate determining step. Thermodynamic studies revealed that the adsorption process was endothermic and physisorption since values of ∆H° obtained were < 40 kJ/mol. From the adsorption data, it‟s evident that synthesized geopolymers are potential adsorbents for removal of heavy metals and MB and may be employed in wastewater management.
BIOEFFICACY OF ORGANIC EXTRACTS OF FISH POISON BUSH (GNIDIA GLAUCA, FRESEN) AGAINST COWPEA WEAVIL (CALLOSOBRUCHUS MACULATUS, FABRICIUS)
(2018-11) WILHELMY MARION JEBET
Cowpea weevil (Callosobruchus maculatus) is a major pests of stored cowpea in the tropical region of the world. In Kenya, the damage caused by C. maculatus impacts negatively on its economic and nutritional values and contributes to food insecurity. The widely adopted use of chemical pesticides is marred with health and environmental hazards. Global concern on synthetic chemicals has led to heightened restrictions and limitations on their use. This, therefore, has prompted the search for alternatives to synthetic pesticides. New studies are focusing on the use of botanicals as a novel approach to the management of pests. Gnidia glauca has been exploited by local people in control of post-harvest pests. However, no scientific research has been undertaken to evaluate its potential anti-insect properties. In this study, four organic leaf extracts of G. glauca (methanol, ethyl acetate, DCM and blend) were evaluated for contact toxicity, oviposition deterrence, inhibition of progeny emergence and repellency against cowpea weevil. The plant leaves were collected from Embu County, Kenya. The samples were prepared, extracted and investigation carried out under ambient laboratory conditions. The experimental design entailed five test concentrations (2g/100ml, 4g/100m, 6g/100ml, 8g/100ml, and 10g/100ml) of each extract, the untreated control, the solvent control and the positive control-Actellic. Each bioassay had four replications. Adult weevils (1-3 days old) were exposed to the extracts and mortality was monitored daily for the first four days. Subsequently, oviposition deterrence was assessed on the 15th day while inhibition of progeny emergence was evaluated on the 49th-day post-treatment. Extract repellency was assessed for the first 6 hours after treatment. Screening for plants phytochemicals was conducted using the standard recommended procedures. The results of this study revealed all G. glauca extracts, to a varied extent, induced mortality on C. maculatus. Mortality was concentration and exposure time dependent. Highest mortality of 89.74% was recorded with 10g/100ml ethyl acetate extract 96 hours post-treatment. The extracts significantly deterred oviposition with the 10g/100ml concentration of ethyl acetate, DCMand blend statistically (p>0.05) comparable to the activity of synthetic pesticide. All the extracts were found effective in inhibition of progeny emergence. Ethyl acetate extract at the test dose of 10g/100ml demonstrated the highest inhibition of 99.3% while the least inhibition of 9.03% was exhibited by 2g/100ml methanol extract. G. glauca extracts proved to be attractant of C. maculatus rather than repellant, none of the extract concentration attained repellency greater than 50%. Results also showed that the extracts had tannins, phenols, flavonoids, terpenoids, saponins, alkaloids, cardiac glycosides and steroids which have been associated with insect control properties. It was therefore concluded that the plant extracts, possess bioactivities against Callosobruchus maculatus on the tested parameters of contact toxicity, oviposition deterrence, inhibition of progeny emergence and repellency. Hence the studied extracts can further be purified and developed into the plant-derived bio-pesticides to control C. maculatus.
ELECTRON IMPACT ELASTIC SCATTERING OF STRONTIUM USING DISTORTED WAVE METHOD
(2018-11) KIMANI MARTIN KIRUGU
Differential and integral cross sections for electron-atom are useful for interpretation and understanding of electron contact with the targets and for determining dynamics of the collision processes. They are useful in X-ray photoelectron spectroscopy (XPS), upper atmosphere dynamics, Monte-Carlo simulation (MCS), Auger-electron spectroscopy (AES), in gaseous-exchange, laser development, plasma physics and fluorescent lighting. For elastic scattering of strontium very few calculations have been performed and currently there are no known results using the present method. Also the available theoretical results do not have other results to be compared with so it makes it important to obtain results to compare them and to be compared with future experimental results. In calculation of differential and integral cross section for elastic scattering of electron by strontium atom, first-order distorted wave born approximation method has been used to determine DCS and ICS at impact energies of 10eV to 200eV and scattering angles ranging from 00 to 1800 . Also in this study at the initial state, both initial and final channel distortion potential of elastic scattering of electron by a strontium atom are taken as the static potentials since it is an elastic scattering. The distorted waves are expanded in terms of radial wavefunctions and spherical harmonics, Numerov method was then used to solve the radial equations to obtain the radial wavefunctions. The Madison and Bartschat computer program DWBA1 for e- - H scattering was modified to perform the mathematical computations for e - - Sr scattering and the results for differential and integral cross sections are calculated and compared with the available results. The integral cross sections (ICS) results agree well qualitatively with the other theoretical results. At lower incident energies (10-30 eV), the present differential cross section (DCS) results disagree with results obtained from optical potential method. This is because the first order distorted wave method gives poor results at low impact energies and also the nature of the distortion potential used. At intermediate and higher energies (60-200 eV), the present DCS results agree well with the results obtained from optical potential method. In conclusion, the DWBA was developed and applied to 𝑒− - Sr scattering, changes on the DWBA1 computer program were made for strontium, differential cross section (DCS) and integral cross section (ICS) at impact energies 10-200eV for elastic scattering of electron-strontium were determined using DWBA at intermediate and high energies and the results compared with the other available results. From this work it was recommended that some experimental studies on electron impact elastic scattering of strontium should be made to give results for comparison with the calculated results, more theoretical studies using other methods should be conducted on DCS and ICS for purposes of comparison with the present results, a distortion potential that incorporates the polarization potential, exchange potential and absorption potential should be used in the calculation and the present method incorporating all the distortion potentials should be extended further for electron impact elastic scattering of other alkaline earth metals such as beryllium, cesium, ytterbium, and radium.
DETERMINATION OF FECAL CONTAMINATION STATUS OF SHALLOW WELLS IN DEDE DIVISION, MIGORI COUNTY, KENYA
(2018-12) OLUOCH EVANCE ODIWUOR
A shallow well is a hole dug, bored or drilled less than 50M deep to extract water. Contamination of shallow wells with fecal matter presents a grave public health threat in developing countries, such as Kenya, where large numbers of households lack access to clean and safe water supplies and rely on untreated surface water sources or shallow unprotected groundwater for domestic utilization. A report by WHO shows that 1 billion people practice open defecation with nine out of ten of them in rural areas and it is estimated that 1.8 billion people use a source of drinking water that is fecally contaminated. In Kenya unsafe water, sanitation and hygiene are the 2nd leading risk factors causing morbidity and mortality at the national and county levels respectively. In Dede Division, 65.5% of households depend on shallow wells for domestic needs and there are rising trends of confirmed cases of fecal-related diseases. The study sought to assess human and technical determinants of fecal contamination status of shallow wells in Dede Division. A cross-sectional study of households using the wells was conducted. Fisher’s formula was then used to calculate the sample size of the heads of households. Since the approximated number of households using shallow wells was <10,000 (4008), the two stages of the formula were adopted, giving a sample size of 386 heads of households. Out of the 180 shallow wells, 54 (30% of 180) were proportionately sampled and grab sampling technique adopted while sampling water from each of the sampled shallow wells. Basic physical parameters like temperature, turbidity and pH were analysed by a portable turbidity meter and pH meter while H2S rapid field test was employed for total corliforms analysis of grab samples in the field. Fecal contamination status of each well was determined by Membrane Filter Technique in kisumu government labaratory. Chi-square test was used to measure associations between variables while Multi-variate logistic regression analysis applied to test the hypotheses. The study reported significant relationship between level of knowledge of respondents on a well being too close to a latrine as a potential route (risk factor), a well located downhill a latrine, an open/uncovered well, surface run-offs into wells, dropping objects in shallow wells, using a dirty drawer, people/animals dropping in wells, doing laundry next to a well, and human/animal feces dropping in the well as potential routes of fecal contamination. It further revealed significant associations between several technical determinants and fecal contamination status of shallow wells e.g distance (M) from a latrine to a well, with majority of wells within safe distances of contamination (>10M) but still tested positive for fecal corliforms, distance (M) from the nearest cattle pen if any with a significant majority of shallow wells testing positive for fecal corliforms, damage or lack of concrete plinth, breaks/cracks on the parapet walls, breaks/cracks in the cover/top slab, breaks in the drainage channels, shallow well covered while not in use and shallow well fenced out respectively. Majority of shallow wells (69%) tested positive for E. Coli, a strong indicator for presence of fecal matter in water, with only 31% testing negative. Common human and technical determinants (risk factors) by and large are functions of fecal contamination status of shallow wells in Dede Division. Efficient protection of shallow wells is a critical pointer to their ground water quality. Households in Dede Division should ensure adequate treatment of shallow wells for fecal contamination before utilization of water from these sources. This can be both at source or household level. They should be sensitized by the relevant authorities on common routes of fecal contamination of shallow well water and safe hygiene and sanitation practices around shallow wells to prevent fecal contamination of the wells. Households using shallow wells in Dede Division should ensure proper sighting and location of latrines in relation to shallow wells to avoid fecal contamination of the wells through leaching. The pit latrines should be sighted down hill the shallow wells and located atleast 10 meters apart.
SOIL MOISTURE CONSERVATION, CROPPING SYSTEMS AND SOIL FERTILITY EFFECTS ON SOIL AND MAIZE PERFORMANCE IN MACHAKOS COUNTY, KENYA
(2019-05) NGIE MWENDE (B. Sc. [Hons], M. Sc.)
The main causes of food insecurity in semi–arid parts of Kenya are low soil fertility, low and unreliable rainfall. These two causes are the main challenges facing small-scale farmers in food production especially in semi-arid areas of the country. To overcome these challenges, soil and water management technologies especially those in soil and water conservation need to be embraced. The aim of the study was to determine the effect of tied ridges, fertilizers and cropping systems on soil properties (moisture, pH and organic carbon), growth and yield parameters of maize; and to identify the most cost effective water and soil management technology. This study was carried out in four seasons at Katumani in Machakos County. The experiment was a 2 x 4 x 2 factorial, laid out in a randomized complete block design (RCBD). The treatments were: tied ridging, flat bed planting, farm yard manure 0 t/ha, farm yard manure 5 t/ha, nitrogen fertilizer 20 kg/ha, farm yard manure 5 t/ha + nitrogen fertilizer 20 kg/ha, maize mono crop and maize cowpea intercrop. Data collected included soil moisture content, soil pH, total organic carbon, growth parameters and maize yield. The results showed that, treatments with flat bed planting in maize mono crop significantly increased soil moisture content at 0–20cm depth as compared to tied ridging in maize cowpeas intercrop during short rains 2015. Application of farm yard manure at 5 t/ha increased soil moisture content at 2 and 4 weeks after planting. The soil moisture content ranged from 6.30% to 23.80%. During the short rains 2015, maize mono crop significantly increased vegetative growth in comparison to maize cowpeas intercrop. Treatment with flat bed and 20 kg N/ha in maize mono crop had the highest mean for vegetative growth. However, during the long rains 2016, treatment with tied ridging and 20 kg N/ha in maize mono crop registered the highest mean for vegetative growth. During the short rains 2015, treatments with maize mono crop significantly increased grain yield with a range of 1.35 t/ha 3.59 t/ha. Flat bed planting with farm yard manure 5 t/ha in maize cowpea intercrop significantly increased the grain yield by 165.93%. The harvest index during the short rains 2015 ranged between 0.35 and 0.48. Treatments with maize mono crop significantly increased gross benefit, net profit, gross margin and cost benefit ratio during short rains 2015 and long rains 2016. Application of farm yard manure 5 t/ha + 20 kg N/ha had the highest variable cost. The cost benefit ratio was positive during the short rains 2015 with a range of 1.47–2.98. The yield differences among the four seasons could have been as a result of variations/distribution in rainfall amount, soil moisture content and soil fertility as induced by the treatments. Flat bed planting increased the yields during the short rains 2015 when the amount of rainfall was high whereas tied ridging resulted in improved yields during short rains 2014, long rains 2015 and 2016 when rainfall amount was low. For the farmers to maximize yields and profits in the study area, adoption of flat bed planting with farm yard manure 5 t/ha and maize cowpeas intercrop during the seasons of high rainfall could be appropriate treatment combination according to the findings of this study. However, during seasons with low rainfall, tied ridging with 20 kg N/ha and maize mono crop could be recommended for adoption. Also, variations in seasonal rainfall should be considered when integrating different soil and water management practices because the effectiveness of different technologies vary with the seasons. Farmers in Machakos County may have to consider use of supplementary irrigation during the dry spells to increase soil moisture.
DERIVATION OF CYCLE INDEX FORMULAS OF SEMIDIRECT PRODUCT GROUPS
(2019-12) Muthoka Geoffrey Ngovi
The concept of the cycle index formulas of a permutation group was discovered in the year 1937. Since then cycle index formulas of several groups have been studied by different scholars. For instance the cycle index of the dihedral group Dn acting on the set of vertices of a regular n−gon is known and has been applied in enumeration of different mathematical structures. In this study the relationship between the cycle index formula of a semidirect product group and the cycle index formulas of the two subgroups which the group is a semidirect product of was established. In particular the cycle index formula of the dihedral group Dn of order 2n is expressed in terms of the cycle index formula of a cyclic group of order two C2 and the cycle index formula of the cyclic group of order n, Cn; the cycle index formula of the symmetric group Sn is expressed in terms of the cycle index formula of the alternating group An and the cycle index formula of a group generated by a cycle of length two, h(ab)i. The cycle index formula of an affine(p) group has been derived by considering the different cycle types of elements of the group and expressed in terms of the cycle index formula of Cp = {x + b, where b ∈ Zp} and the cycle index formula of Cp−1 = {ax, where 0 6= a ∈ Zp}. We further extend this to affine(q) where q is a power of a prime p and to the affine square(p) and affine square(q) groups. Finally, the cycle index formula of a Frobenius group is expressed in terms of the cycle index formula of the Frobenius complement H and the cycle index formula of the Frobenius kernel M. The cycle index formulas which are known such as that of the dihedral group and the symmetric group were used and the groups whose cycle index formulas are not known such as the affine(p), affine square(p), affine(q) and affine square(q) group were first derived as part of the research. It was noted that for semidirect groups which are Frobenius such as the dihedral group Dn with an odd value of n, the affine groups and the affine square groups, we can fully express the cycle index of the group in terms of the cycle index formulas of the subgroups which the group is a semidirect of. However, for semidirect product groups which are not Frobenius such as the dihedral group Dn with an even value of n and the symmetric group Sn, the cycle index formula of the group cannot be expressed fully in terms of the cycle index formulas of the subgroups the group is a semidirect product of.

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