Jomo Kenyatta University Of Agriculture And Technology Research Articles

Role of Church Affiliation and the Sexual Behaviour Choices of Students in Selected Universities in Nairobi County, Kenya

Purpose: The current study sheds light on the role of church affiliation in shaping sexual attitudes and behaviour. Not enough was known about how Christianity can influence the construction of values and beliefs that discourage risky sexual behaviour among adolescents at universities in Kenya. Little was understood on the role of church affiliation explaining variation in adolescent sexuality among Christian communities at universities. Spirituality is an understudied subtype of religiosity yet it may explain patterns of sexual behaviour. Most studies that have examined the relationship between sexual behaviours and religiosity have focused on sexual intercourse. These studies have not examined other sexual behaviour choices, like internet sex.
 Methodology: Using a mixed-methods design, the relationship between church affiliation and sexual behaviour was examined. In quantitative analysis, a stratified probability sample of (n=176 students) who attend regular prayer sessions in three universities: the Kenyatta University (KU) Main Campus, the Jomo Kenyatta University of Agriculture and Technology (JKUAT) Karen Campus, and the Daystar University was used. Qualitative interviews were conducted with university administrators, chaplains, and other church workers. Undergirding the study was the social identity theory, which articulates the idea of people seeking to gain membership and acceptance in any social group.
 Findings: The findings suggest church affiliation has a significant effect on sexual attitudes, values, and behaviour. There seems to be an interaction between extrinsic and intrinsic religiosity, with frequent church attendance appearing to induce more conservative sexual beliefs, attitudes and behaviour. Church affiliation had a significant effect on sexual behaviour choices, which includes internet sex and cohabitation and extreme sexual activities.

The effect of indigenous Arbuscular mycorrhizal fungi (AMF) on phyto-accumulation in Carica papaya hybrids

Papaya (Carica papaya L.) is a climacteric fruit with a resilient and distinctive aroma. The consumption of the fruit is global due to its high nutritive and medicinal values. However, there has been low production of quality papaya fruits due to unavailability of crucial mineral elements in the soils. The current study therefore, focuses on the effect of indigenous arbuscular mycorrhizal fungi (AMF) as a biofertilizer on the quality of papaya fruits. In order to verify AMF effectiveness on papaya fruits, four treatments were used: AMF inoculum only, composted farm yard manure (FYM) only, combination of AMF inoculum and compost FYM and control where only soil and sand media were used at a ratio of 1:1. Jomo Kenyatta University of Agriculture and Technology (JKUAT) and Malkia papaya hybrids were used. The papaya seeds from JKUAT and Malkia papaya hybrids were sown in trays and transplanted at 3 leaves stage into 5 litre pots within a green house. The AMF spores were bulked using sorghum plants to obtain the AMF inoculum. The treatments were added into the soil media of the papaya plantlets at a ratio of 1:3, every 4 weeks after first transplanting until they were 20 weeks old. They were then transplanted to 100 litre containers, where completely randomized design was used and replication of six papaya plants for each treatment and hybrid. Watering, weeding and cooling the green house with water fumes was carried out when necessary; as the papaya plants grew until the fruits attained physiological maturity. The fruits were separately harvested and ripened to a predetermined stage. They were then analysed for moisture content, crude fibre, minerals (nitrogen, phosphorous, potassium, magnesium, calcium, iron and zinc), ascorbic acid, total carotenoids and total polyphenols. Data obtained was subjected to two-way ANOVA at p ≤ 0.05 significance level; means were separated using Tukey's HSD test in Genstat's 15th edition. JKUAT hybrid with AMF inoculum treatment had 3.07%crude fibre and 8.42mg/100g phosphorous content while JKUAT hybrid with both AMF inoculum and manure treatments had 4.9 % crude fibre and 9.88 mg/100g phosphorous content. Malkia and JKUAT hybrids with compost FYM treatment had potassium content of 98.31mg/100g and 109.4 mg/100g respectively while the controls had 31.58 mg/100g and 35.32mg/100g respectively. Incorporating soil media with manure and AMF inoculum improved the nutritive quality of papaya fruits and this was contingent on papaya hybrids. Key words: biofertilizer, inoculum, mineral elements, nutritive quality, physiological maturity

Economic analysis of biogas production from pineapple waste as alternative source of energy in a pineapple processing plant, case of Del Monte Kenya Limited

<p>This paper evaluates the economic aspect of utilizing biogas from pineapple waste as a source of energy in a pineapple processing plant, case of Del Monte Kenya Limited (DMKL). Del Monte Kenya Limited, a known exporter of canned pineapple, lies on approximately 10,000 acres of pineapple plantation. The company’s processing capacity of 100,000 tons of pineapple yearly produces approximately 23,000 tons of pineapple waste per year. Currently these wastes are sold to local farmers as animal feed at $20 per ton. A study was conducted at Jomo Kenyatta University of Agriculture and Technology (JKUAT) that revealed that a ton of pineapple waste has the potential to generate 7.41 m<sup>3</sup>/day of biogas. Cost comparative analysis was conducted between employing anaerobic digester to treat pineapple wastes to generate biogas for usage within the plant and selling the waste to locals for feeding the livestock. The results revealed that it is more economical to use wastes to generate biogas as an alternative source of energy in the processing lines. The net present value (<em>NPV</em>) of $1,939,019 internal rate of return (<em>IRR</em>) of 16% and payback period of 4 years was estimated. The positive value of <em>NPV</em> shows that the project is viable.</p>

Genome‐wide association study of variation in cooking time among common bean (Phaseolus vulgaris L.) accessions using Diversity Arrays Technology markers

AbstractStored grains of common bean (Phaseolus vulgaris L.) develop the hard‐to‐cook trait (HTC), which is manifested in a prolonged cooking time, thereby imposing time and energy constraints. The objective of this study was to determine variation in cooking time among common bean genotypes and to identify single nucleotide polymorphism (SNP) markers associated with cooking time.Seeds of 222 common bean accessions sourced from Kenyan institutions were multiplied in the Jomo Kenyatta University of Agriculture and Technology (JKUAT) field in 2019. The freshly harvested seeds and those stored at 35°C and 50% red haricot (RH) for 4 months for accelerated aging were soaked in distilled water for 16 h and evaluated for cooking time using the finger‐pressing method. The accessions were also genotyped to determine variation in SNP markers using Diversity Arrays Technology Sequencing (DArTseq). Genome‐wide association study (GWAS) analysis was conducted to identify SNPs significantly associated with cooking time.The study revealed significant differences (p ≤ 0.05) within and between fresh and aged bean accessions. Fresh seeds had a lower cooking time with a mean of 40.8 min and ranged from 28.1 to 72.2 min, whereas aged seeds had a higher average cooking time of 54.1 min and ranged from 32.1 to 96.3 min. GWAS identified a region in Chromosome 10 to be significantly (p ≤ 0.05) associated with the cooking time of aged seeds. Consequently, two potential candidate genes Phvul.010G038000 and Phvul.010G038100 were revealed. The characterized common bean accessions and the identified SNP markers can be utilized in breeding programs to improve the cooking quality of the common bean.

Factors influencing the adoption and use of open access scholarly publishing in selected public universities in Kenya

The purpose of the study was to explore the factors that influence the adoption and use of open access scholarly publishing (OASP) by researchers in selected public universities in Kenya. Using the Unified Theory of Acceptance and Use of Technology (UTAUT) model as a study lens and the questionnaire as the data collection tool, the study collected data from academic researchers in three Kenyan public universities, namely the University of Nairobi (UoN), Kenyatta University (KU) and Jomo Kenyatta University of Agriculture and Technology (JKUAT).The findings of the study indicate that there are several factors associated with facilitating conditions (FC), performance expectancy (PE), internet skills, and social influence (SI) that influence there searchers’ intention to adopt and use OASP in the selected universities. Consequently, we believe that addressing the inhibitors of the adoption of OASP in Kenyan universities would be key to the successful and effective use of OASP. Enablers such as ICT infrastructure, staff capacity and clear policies should be enhanced so as to optimise researchers’ capabilities. Based on the findings, the study makes several recommendations to improve the adoption and use of OASP in Kenya’s institutions of higher learning.

Effect of Drying Method on Volatile Nutraceuticals and Microbial Growth in Moringa oleifera

Fresh Moringa oleifera leaves are very rich in phytonutrients, however the leaves are also highly perishable and require processing for increased shelf-life. The method of processing, specifically drying affects the nutritional value of the product. The present study therefore, analyzed the nutraceutical value and growth of toxic microbes when the leaves were dried under different conditions i.e. room temperature, greenhouse, 50% shade net, and in the oven at 60 oC for 4 h. The experiments were carried out at the Jomo Kenyatta University of Agriculture and Technology (JKUAT). The treatments were applied in triplicate and arranged on a completely randomized design (CRD). Data on nutritional value of dried Moringa leaves was subjected to analysis of variance (ANOVA) for parameterization and means separated using protected LSD0.05. The study showed that drying Moringa leaves under shade, room and greenhouse conditions significantly (P<0.05) affects the nutritional value of the product. The results showed highest levels of vitamin C, vitamin A, polyphenols and terpenoids when the leaves were dried under 50% shade net and room temperature conditions. In contrast, the glucosinolate content was significantly (P<0.05) higher when the leaves were dried instantly in the oven (9.1%/wt), followed by drying under greenhouse conditions (8.7%/wt) before oven drying. However, drying of Moringa leaves under shade before oven drying resulted in growth of toxic microbial organisms such as staphylococcus, yeast, E. coli and molds that can potentially affect the safety of the product. Finally, the drying conditions also significantly (P<0.05) affected the moisture content of the powder obtained. The results of this study form an important reference for small-holder Moringa growers and processors in the development of an optimal processing regime for high value Moringa powder.

English

Papaya is one of the most important fruits crops of Kenya. However, in the recent past, papaya productivity and quality have been limited by lack of high quality seeds. Most producers depend on farmer selected and imported seeds for propagation. However, this is not satisfactory since few farmers can afford imported seeds due to their high price. On the other hand, most of the farmer selected seeds give rise to trees with inferior fruit quality and are susceptible to diseases. The above mentioned challenges necessitated the development of new Jomo Kenyatta University of Agriculture and Technology (JKUAT) papaya lines with superior qualities to help boost fruit production. So far, the new JKUAT papaya has been evaluated only at JKUAT main campus in Kiambu County. This study evaluated the performance of newly developed JKUAT papaya lines (Line 1, 5, 6 and 7) in different agro-ecological zones of Kenya. The study sites were JKUAT (upper midlands zone), Nkubu (upper highlands zone), KALRO Mwea (upper midlands zone) and Mitunguu irrigation scheme (upper highlands zone). The results on morphological, fruiting and biochemical quality showed significant differences. The total number of fruits varied significantly where line 1 had the lowest number (84 fruits) in JKUAT and the highest number was recorded in line 5 (134 fruits) in KALRO, Mwea. The fruit weight varied significantly and ranged from 1.2 kg in line 5 in JKUAT to 2 kg in line 7 in KALRO Mwea. The total soluble solids (TSS) varied significantly from 8.3% in line 7 in KALRO Mwea to 13.7% in line 5 from Nkubu. The results revealed that new lines had good productivity and they should be commercialized in Kenya. However, there is a need to determine the performance of the newly developed papaya lines under heat and water stress conditions. Key words: Agro-ecological zones, fruit quality, fruit yield, morphology, papaya lines.

Characterization of Polyphenols, Flavonoids and Their Anti-microbial Activity in the Fruits of Vangueria madagascariensis J. F. Gmel

Aim: The study aimed to characterize phenolic acids, flavonoids, and determine their antimicrobial activities in fruits of Vangueria madagascariensis (Tamarind of Indies).&#x0D; Study Design: The design of the study included picking of Vangueria madagascariensis fruits from Jomo Kenyatta University of Agriculture and Technology (JKUAT) botanical garden and analysis for their antimicrobial activities at the Botany department research laboratory, JKUAT. Characterization of phenolic acids and flavonoids were conducted at MacEwan University Canada.&#x0D; Place and Duration: JKUAT, Kenya and MacEwan University, Edmonton, Alberta Canada between June 2013 and June 2016.&#x0D; Methodology: Phenolic acids and flavonoids from Tamarind of Indies were determined by high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MSN). The antimicrobial assay was determined using the disk diffusion method.&#x0D; Results: Based on the retention time, the UV spectrum, and the tandem MS behavior, the results revealed a profile composed of 25 phenolic compounds. Some of the identified phenolic compounds included: 3-caffeoylquinic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, 4-feruloyl quinic acid, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin, 3,4-di-caffeoylquinic acid, 4, 5-di-caffeoylquinic acid, kaempferol, diosmetin, caffeic acid, epicatechin, kaempferol 3-O-glucoside. The fruit extracts had a probable presence of quercetin 3-O-6’-malonylglucoside, ikarisoside C, epimedin C, unknown epigallocatechin-3-gallate and quercetin conjugate derivatives. Furthermore, the fruit extracts from Vangueria madagascariensis showed appreciable antimicrobial properties against human pathogen strains. Strong antimicrobial activity was observed for Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The Vangueria madagascariensis was found to be highly potent against Escherichia coli and Bacillus subtilis even at low concentrations of 0.1 mg/mL.&#x0D; Conclusion: The research findings may suggest value of the use of Vangueria madagascariensis fruits as a rich source of antioxidants with therapeutic and nutraceutical value.

Monochoria africana N.E.Br. [Family Pontederiaceae]: Probable Reasons for Limited Distribution of This Rare Species in Kenya

Monochoria africana N.E.Br. is an extremely rare plant with limited distribution in Kenya. Rare plant species are often specialists for a rare microhabitat and there is all likelihood that Monochoria africana is a habitat specialist. Our research on distribution of this species in Kenya has so far located it in a very small isolated microhabitat in the Tana River delta, coastal region of Kenya. So far, this plant has only been located in one community farm in a small village called Ozi, near Kipini, Latitude 2°30’33’’S and Longitude 40°27’20’’E. The methodology used in this study entailed direct observations, line transects, meander and patterned searches in its narrow area of endemism.&#x0D; In this short communication, the authors hypothesize various reasons for the limited distribution of this rare species. Viz: diverse edaphic factors, inbreeding depression, low levels of seed set, genetic bottlenecks, specialized pollination systems etc. At the Jomo Kenyatta University of Agriculture and Technology (JKUAT) department of Botany greenhouses, we have embarked on some studies to try and unravel probable reasons for rarity of Monochoria africana.

Safety and Fertility Potential of Kenyan Grewia tenax (Mukawa Wa Guba) Root Extract Secondary Metabolites

Aim: To screen Kenyan Grewia tenax root extract phytochemicals and correlate the attribute fertility enhancing effects and safety in female albino rats.&#x0D; Study Design: An experimental study design was used.&#x0D; Place and Duration of Study: The phytochemical studies were done at Jomo Kenyatta University of Agriculture and Technology (JKUAT), Department of Botany Laboratory, while acute oral toxicity studies were done at the Department of Veterinary Anatomy and Physiology, University of Nairobi (UON) animal house. The study was done during the month of March to June 2019.&#x0D; Methodology: Grewia tenax was harvested with the help of a plant taxonomist. The roots were chopped into small pieces and dried under shade for three weeks. They were then ground into powder. Organic extracts were prepared by sequential extraction (petroleum ether, dichloromethane (DCM), ethyl acetate and methanol), by use of cold maceration. Aqueous extracts were obtained by hot maceration. Phytochemical screening of extracts was done by standard phytochemical procedures. A total of 12 female albino rats were used in acute oral toxicity studies as per OECD 423 guidelines.&#x0D; Results: Methanol extract had the highest composition of phytochemicals, i.e. alkaloids, flavonoids, saponins, sterols, terpenes and cardiac glycosides. Aqueous and DCM extracts showed presence of alkaloids, saponins and cardiac glycosides, while petroleum ether and ethyl acetate extracts showed presence of alkaloids and cardiac glycosides. Steroids and tannins were absent in all extracts. Flavonoids, alkaloids and terpenes are fertility enhancing compounds due to their antioxidant and radical scavenging properties. Flavonoids, alkaloids and glycosides improve fertility by inducing ovarian steroidogenesis and folliculogenesis. In the acute oral toxicity study, there were no adverse effects at 5000 mg/kg extract administration.&#x0D; Conclusion: Kenyan Grewia tenax root extract has phytochemicals postulated to enhance fertility and is orally safe. These findings may require further verification using in vivo studies.

Optimal Operation Control of Microgrid Connected Photovoltaic-Diesel Generator Backup System Under Time of Use Tariff

With the exponentially increasing demand of electrical energy, many developing countries are struggling to provide electricity to the end-users. This challenge has mainly strained traditional power systems. To mitigate against this strain, governments are diversifying and liberalizing the energy market to meet future energy demand. In addition, end-users have several alternatives to reduce electricity cost at demand side. This can be realized either by using efficient devices or incorporating renewable energy sources while scheduling their powers economically. Within this framework, microgrids are considered as efficient power systems to exploit renewable energy sources with demand side management program. Nowadays, microgrids which can harness photovoltaic solar source at low cost are becoming an attractive option for reduction in electricity cost at demand side. To ensure uninterrupted power supply, diesel generators are often used as backup energy systems in most large-scale or industrial applications in Kenya. Therefore, this paper proposes a constrained optimal operation control strategy of microgrid connected photovoltaic with diesel generator backup system related to commercial and industrial (C&I) setups in Kenya. Particularly, the objective function simultaneously aims at reducing energy purchased from utility grid and the fuel consumption cost of the conventional diesel generator. The constraints related to control variables are taken in the context of C&I in Kenya. The optimal operation control is carried out using FMINCON interior-point algorithm, and two scenarios are analysed. The first scenario is carried out by considering the intermittent mode from 7:00 hrs to 18:00 hrs, while the second scenario is considered in the intermittent connected mode. A case study is done based on the daily load profile of the Engineering workshops at Jomo Kenyatta University of Agriculture and Technology (JKUAT) located at $$-$$ 1.099 $$^{\circ } $$ latitude and 37.014 $$^{\circ } $$ longitude. The optimal operation control has shown great benefits in terms of energy saving, cost saving as well as daily revenue. The daily energy saving is increased up to 52.1%, the daily cost saving is 20%, and daily energy sold is found to be 142.4 kWh which can generate daily income of $17.

Chemical composition, antioxidant potential and antimicrobial activities of Ixora scheffleri subspecies keniensis essential oil

Background: Essential oil (EO) obtained from Ixora scheffleri subspecies (subsp.) keniensis has valuable biological properties and can play a possible therapeutic role because of its antimicrobial and antioxidant nature. Aim: In this article, the chemical constituents, antimicrobial activity and antioxidant capacity of the EO obtained from Ixora scheffleri subsp. keniensis were determined using standard procedures. Setting: Plant material collection, essential oils extractions and antimicrobial assays were performed at Jomo Kenyatta University of Agriculture and Technology (JKUAT), Department of Botany Laboratories. Gas Chromatography Mass Spectrophotometry (GC/MS) analysis was carried out at the Physical Science Laboratory, MacEwan University, Canada. Methods: The chemical constituents were determined using GC/MS. The total phenol content was evaluated using the Folin–Ciocalteu procedure. The antioxidant activity was determined using 2,2-diphenyl-1- picrylhydrazyl (DPPH) and β -carotene linoleic acid assays. The antimicrobial assay was performed using the disc diffusion method. Results: The total phenol content of the EO was estimated to be 91.6 µ g/mg ± 0.5 µ g/mg. The antioxidant activity of EO obtained from Ixora relative to ascorbic acid was found to be 52% using the β -carotene linoleic acid assay. The DPPH scavenging activity of 30 µ g/mL EO obtained from Ixora and 30 µ g/mL ascorbic acid was 81.65% and 97.0%, respectively. The EO was found to have significant susceptibility against Escherichia coli , and intermediate susceptibility against Candida albicans . However, Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa showed complete resistance. Conclusion: The in vitro chemical compositional analysis of EO obtained from Ixora scheffleri subsp. keniensis confirms the presence of phenolic compounds attesting to the antioxidant properties and antimicrobial properties.

Evaluation of Levels of Cadmium, Chromium and Lead in Bio Fertilizer from Various Feed Stocks and in Inorganic Fertilizers Used in Kenya

This study was conducted to compare the levels of selected heavy metals (Pb, Cr and Cd) in inorganic fertilizers and bio slurry from different feed stocks. Bio slurry samples from chicken droppings, cow dung and pig wastes were analyzed for levels of selected heavy metals. Inorganic fertilizers for analysis DAP, CAN, Urea and NPK were procured from local market in Juja town next to Jomo Kenyatta University of Agriculture and Technology (JKUAT). Bio slurry samples were collected from Githunguri Sub County in Kiambu County and from mini digesters set up at JKUAT. Concentrations of Cd, Cr, and Pb were determined by Flame Atomic Absorption Spectrophotometer (Shimadzu 6200). Inorganic fertilizers were found to contain detectable amounts of lead metal. DAP had the highest amount of Pb at 0.03 mg/l followed by CAN (0.02 mg/l) Urea and NPK had 0.01 mg/l each. Bio slurry samples contained lower amounts of lead which was below detectable limit in chicken litter and pig wastes. Inorganic fertilizers contained Cd with the highest levels being in the phosphorous containing fertilizers DAP (0.41 mg/l) and NPK (0.48 mg/l). All samples contained Cr with the highest in bio slurry samples being 0.09 mg/l in cow dung collected from Githunguri. CAN had the highest level of Cr (0.08 mg/l) among the inorganic fertilizers. Bio slurry is a better alternative fertilizer in reducing heavy metal uptake and their subsequent bioaccumulation.

Assessment of Drinking Water Quality in Umoja Innercore Estate, Nairobi

Water quality is one of the main indicators of the quality of service provided to consumers. Quality has an impact on both the public health and aesthetic value of water as a consumable product. Kenya is classified as a water-scarce country with only 647 cubic meters of renewable freshwater per capita. Water distributed in Nairobi is faced with a myriad of challenges leading to a compromise to its quality. This study focused on evaluating quality of drinking water since human health depends on adequate, clean, reliable water. Analyses were carried out at National Environmental Management Authority (NEMA) accredited Jomo Kenyatta University of Agriculture and Technology (JKUAT) laboratories to determine the chemical, bacteriological and physical characteristics of consumed water in Umoja Innercore Estate in Nairobi. In the study area, 7 HH and 6 BH sites were randomly distributed. pH, turbidity and temperature measurements were analyzed in-situ while bacteria and chemicals were analyzed in laboratories. The study found that 100% of boreholes recorded unsatisfactory water with up to 1100 of Escherichia coli (E. coli) showing high contamination with faecal coliforms and 83% of boreholes recording pH of up to 9.53. Dissolved oxygen was 5.08 mg/L below recommended 12.0 mg/L, salinity of 0.47 mg/L and 0.03 mg/L for boreholes and households respectively. The study reveals the deprived quality of water available to the residents of Umoja Innercore, Nairobi. The study recommends the use of biosand filtration methods for septic tanks, digging of deeper boreholes and lining septic tanks with impermeable materials to prevent contamination of ground water with raw water from septic.

Multi-objective optimal sizing of grid connected photovoltaic batteryless system minimizing the total life cycle cost and the grid energy

The increasing demand of electricity has led to drastic use of renewable energy resources because of the scarcity and environmental effects of fossil fuel. Photovoltaic energy is one of renewable energy sources that emerges exponentially due to its environmentally friendly, operating and maintenance free, among other benefits. However, the main drawback of photovoltaic energy is its unreliability due to unpredictable nature of solar. Thus, this paper tackles a novel optimization technique based on multi-objective sizing of grid connected photovoltaic without energy storage systems. The objective aims at minimizing the total life cycle cost (TLCC) and energy purchased from utility grid while maximizing the reliability. In this study, the microgrid system reliability is expressed by the loss of power supply probability (LPSP). Mixed integer linear programming has been used to determine the decision variables which are the optimal number of photovoltaic panels and the hourly powers from utility grid. A case study has been done based on daily power demand of Engineering workshops at Jomo Kenyatta University of Agriculture and Technology (JKUAT). From the results obtained, the optimal number is 354 photovoltaic arrays, 0.6022 kWh is purchased from the grid from 7:00 h to 18:00 h, and the total life cycle cost of the project is found to be 191630$. The daily potential energy saving is up to 64.16%.

PERSONAL COMPUTER-BASED CONTROL AND MONITORIBG SYSTEM FOR BIODIESEL ALGAE PHOTOBIOREACTOR

Growing of Algae for biodiesel production has gained popularity in recent times. This is becausebiodiesel from algae has an economic advantage over other oil crops. The oil content that can beextracted from microalgae biomass depends on the culture conditions and microalgae species. Thismeans that besides selecting the best microalgae species, it is also necessary to ensure and maintain thebest culture conditions for optimal biodiesel production. Optimum algae growth conditions can be bestbe provided by a Controlled Environment Bioproduction System (CEBS) for the algae called as photo-bioreactor (PBR). This paper reports design and fabrication of a PC based control system for a PBRproduction system for algae being developed at the School of Biosystems and EnvironmentalEngineering (SoBEE) in Jomo Kenyatta University of Agriculture and Technology (JKUAT) in Kenya.The control system is intended to ensure that optimum PH, temperature, nutrients content; lightintensity/duration and salinity of growth medium for algae are maintained. The paper covers the designand fabrication of the PC control and monitoring system. The control and monitoring system consists ofa computer program and a microcontroller connected to sensors and actuators. The computer program(master) provides the graphical user interface (GUI) consisting of control buttons and means for realtime data logging and analysis as well as real-time simulation of PBR activities. It is available inexecutable file that can be run in any windows OS computer. The microcontroller program (slave)provides the means for connecting sensors and is used to measure as well as monitor the conditions inthe PBR tanks. Communication between the computer program and the microcontroller is achievedthrough the universal serial bus (USB). The control system consists of both open and closed loopsystems. The open loop system is used to control the light duration at predetermined intervals of time.The closed loop system is used to control the nutrient concentration, light intensity, PH and oxygen:carbon dioxide ratio.

Status of e-learning Quality in Kenya: Case of Jomo Kenyatta University of Agriculture and Technology Postgraduate Students

There is a substantial increase in the use of learning management systems (LMSs) to support e-learning in higher education institutions, particularly in developing countries. This has been done with some measures of success and failure as well. There is evidence from literature that the provision of e-learning faces several quality issues relating to course design, content support, social support, administrative support, course assessment, learner characteristics, instructor characteristics, and institutional factors. It is clear that developing countries still remain behind in the great revolution of e-learning in Higher Education. Accordingly, further investigation into e-learning use in Kenya is required in order to fill in this gap of research, and extend the body of existing literature by highlighting major quality determinants in the application of e-learning for teaching and learning in developing countries. By using a case study of Jomo Kenyatta University of Agriculture and Technology (JKUAT), the study establishes the status of e-learning system quality in Kenya based on these determinants and then concludes with a discussion and recommendation of the constructs and indicators that are required to support qualify teaching and learning practices

Low Cost Filtration of Domestic Wastewater for Irrigation Purpose

Water scarcity in developing countries has forced farmers to use sewage as an alternative source of irrigation water. However, the usage of sewage for vegetable production has been known to cause excessive and often-unbalanced addition of nutrients hence posing a threat to food safety. The objective of this study was to determine the efficacy of slow sand filter and wetland plant in domestic wastewater treatment. To achieve this objective, samples were collected from the domestic wastewater collection pond within Jomo Kenyatta University of Agriculture and Technology (JKUAT). Laboratory tests were conducted on the collected samples and they revealed the presence of BOD, DO, pH, TDS, Sulfates, Chloride, Turbidity, Salinity, Conductivity, Alkalinity and Coliform; whose values varied when compared with that of the parameters for standard irrigation water. This gave insight to the kind of treatments and filtration medium that were required to transform domestic wastewater into water fit for irrigation. A slow sand filter bed was designed and constructed using precisely six samples materials; sand, sand and wetland plants, gravel, gravel and wetland plants, mixture of gravel and sand, mixture of gravel and sand with wetland plants. These materials were used to identify the chemical and biological changes in domestic wastewater within a seven-day period. The water collected from the slow sand filter was tested, results showed that, of all six samples, slow sand filter using the mixture of gravel, sand with wetland plants had an average percentage efficient of 90% in removing all impurities from domestic wastewater thereby turning it into water suitable for irrigation. It is hoped that this study will provide a safe, easy, eco-friendly and cheap method of wastewater treatment while ensuring the sustainability of wastewater for irrigation and the expansion of green spaces in urban and peri-urban areas.

Rhizoclonium grande Bioethanol in Biofuel Production by Transesterification of Jatropha curcas Oil

There is a need for an alternative sustainable fuel based on renewable sources and efficient carbon dioxide scrubbers. Alkyl esters prepared by transesterification of vegetable oils from various plants have been evaluated. In this work the potential of sustainable macroalgae bioethanol in biofuel production by transesterification of Jatropha curcas oil was assessed. Rhizoclonium grande macroalgae was collected from Shimoni shores in Kwale, Shelly beach in Mombasa, Jamvi la Wageni in Mtongwe Likoni, English point near Kenya Marine and Fisheries Research Institute (KMFRI) Mombasa, dried and processed to obtain 5.36% ± 0.355% v/w bioethanol using Aspergilus niger for hydrolysis and Saccharomyces cerevisiae for fermentation. J. curcas seeds were collected from contracted farmers of Energy Africa in Shimba hills, Coast region. Oil from the seeds was machine cold pressed and solvent extracted using n-hexane giving 44% - 53%v/w yield. The physicochemical properties of the J. curcas oil were investigated. Transesterification of J. curcas oil was carried out using bioethanol from the algae with 63% - 70% FAEE yield. Characterisation of the bioethanol and ethyl esters was done using GC-MS. Physicochemical and fuel properties of the biofuel were investigated at Technical University of Mombasa (TUM), Jomo Kenyatta University of Agriculture and Technology (JKUAT), Government Chemist and Kenya Pipeline Laboratories in Mombasa. There was significant difference in physicochemical and fuel properties observed in density, calorific value, kinematic viscosity, pour point and cloud point between the Jatropha oil and Jatropha fatty acid ethyl esters (JAT FAEE) samples. No significant difference observed in the physicochemical and fuel properties between the JAT FAEE and standard biodiesel samples. This was according to statistical analysis of data done using STATA/SE 13.0 and Xlstat at 95% confidence level (P < 0.05) two-tailed. From the findings bioethanol from R. grande biomass used in transesterification has a potential to improve the sustainability, physicochemical and fuel properties of biofuel from J. curcas a non-food crop. The effect of the use of bioethanol and its byproduct on shelf life of the biofuel can further be investigated.

Linking Practical Spss Training to Research Competence Among Postgraduate Students at Jomo Kenyatta University of Agriculture and Technology (JKUAT), Westland’s Campus

Purpose: The purpose of the paper is to assess the effectiveness of the practical SPSS training to postgraduate students’ research competency.Methodology: An explanatory research design was used to establish the relationship between practical SPSS training and research competence of students. The population was 20 students and a census of the full population was taken. A questionnaire was administered at the end of the training to capture the pre and post training experience and test the effectiveness of the training. The analysis of the data was conducted through descriptive and inferential statistics. In particular, frequencies, means, standard deviations and paired t-test were used.Results: The post training evaluation results reveal that majority of the respondents had low knowledge in data entry, descriptive statistics, regression and correlation analysis, parametric and non-parametric analysis, and journal article extraction and publication. Results also reveal that the level of knowledge significantly increased after the training. This is supported by the paired t-tests conducted on each aspect of training.Unique Contribution to Theory, Policy and Practice: It was recommended that it would value to organize practical SPSS trainings regularly at the campus. It was suggested that University may consider supporting the training financially or the students to be requested to pay a token fee to make the training sustainable. In the event, that these recommendations were untenable, it was suggested that the training consultant to look for funding from the National Research Fund. It was also suggested that the training can be made compulsory for all students undertaking Business Research Methods and points to accrue once they attend the training. Further, trainings workshops can be used to test pedagogical theories which establish the right mix of training techniques, between theory based, practice based and the blend of theory and practical approaches to training.