Department of Science, Technology and Engineering

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Predicting daily streamflow in ungauged rural catchments: the case of Masinga catchment, Kenya
(Taylor&Francis, 2007) Mutua, Benedict Mwavu; Klik, Andreas
Access to daily streamflow data at the catchment scale, is a central component of many aspects of water resources and water quality management. However, the majority of river reaches in many catchments in Kenya are ungauged or poorly gauged, and in some cases existing measurement networks are declining. Long-term continuous monitoring is not being done due to high costs of equipment maintenance. Therefore, there is a need for an alternative tool such as a catchment-scale hydrological model that is capable of predicting the daily streamflow. An approach is presented of predicting daily streamflow using a physically-based catchment-scale model, the geospatial Stream Flow Model (SFM). The SFM was developed using the “C” programming language and the user interface was developed using the Avenue script of the ArcView software. The SFM simulates the dynamics of runoff processes by utilizing remotely sensed and widely available global or local data sets. The model was applied in the Masinga catchment, Kenya, and the results gave a model performance coefficient of 0.74 based on the Nash-Sutcliffe statistical criterion.
Effects of static electromagnetic fields at 24 hours incubation on the germination of rose coco beans (phaseolus vulgaris)
(2009-05) Odhiambo, J.O.; Ndiritu, F.G.; Wagara, I.N.
This study evaluates the percent germination of Rose coco beans (Phaseolus vulgaris L.) seeds, when exposed to static electromagnetic fields under laboratory conditions incubated for 24 h. This can be replicated in the field to aid short period production of beans, hence higher yield. For a given set of sample, germinating bean seeds were exposed to field generated by Helmholtz coil, North Pole or the South Pole with constant magnetic fields of 5 mT, 10 mT, 30 mT and 60 mT. The exposure period was fixed at 3, 4.5 and 6 h and exposed after 12 h incubation. The germinating seeds were counted after 24 h. Certain trends could be observed; statistical analysis has shown that there is statistical influence (p < 0.05, ANOVA test) of the magnetic treatment on germination of rose coco beans. Maximum seed germination occurred when exposed to South Pole field inducing percent germination of approximately 73% compared to 52% of the control at field strength of 30 mT at exposure period of 4.5 h. The research achieved its aim of proving the influence of static electromagnetic field to germination of seeds in addition to, challenging seed companies to come up with magnetized seeds that will germinate faster.
The influence of AC electromagnetic fields on the initial radicle growth rate of phaseolus vulgaris L.
(FACT Limited, 2009-10-07) Odhiambo, J.W.; Ndiritu, Francis G.; Wagara, Isabel N.
Objectives: To determine if AC electromagnetic fields can be used to improve growth of food crops. This would reduce and minimize contamination of yield that is associated with application of fertilizers to promote plant growth and chemicals to control pests and diseases. Methodology and results: Alternating 50Hz electromagnetic fields generated by Helmholtz coil of 0, 5, 10, 30 and 60mT were applied to germinated Rosecoco bean (Phaseolus vulgaris L.) seedlings. For a given sample, seedlings were exposed to AC electromagnetic field for 3, 4.5 and 6h per day. The radical length of beans was measured after every 12h over a 4 days incubation period. Linear regression analysis showed that the incubation period significantly influenced bean radicle elongation with mean optimum rate of 0.088cm/hr after incubation for 66h. Exposure period and strength of electromagnetic field did not significantly influence the initial rate of radicle elongation of Rosecoco beans. Conclusion and application of findings: Beans growing naturally have a more uniform increase in length than those exposed to AC electromagnetic fields. The growth regulators (hormones) are accelerated after exposure to magnetic field hence higher elongation of radicle. Further research on this need to be done especially if the pretreatment of seeds will give the same results so that it can be used in developing better quality and fast growing bean seed.
Effects of different agroecosystems on prevalence of different species of pests and coccinellid predators
(2012) Nyukuri, Robert W.; Wanjala, Fred M.E.; Cheramgoi, Evelyn; Odhiambo, J.O.; Kirui, Stella C.
Abstract: This study was aimed at determining the effects of mixed and single cropping agroecosystems on the prevalence of different species of insect pests and coccinellids. It involved six growing crops: maize Zea mays L., beans Phaseolus vulgaris L. and cowpeas Vignaunguiculata L. Walp in single and mixed stands and sampling throughout the phenology of the crops. Eight insect pest species were recorded on maize grown alone, while thirty seven insect species were endemic on cowpea mono cropped and were of six orders whereas twenty two insect pest species occurred on beans. The predator population was most abundant in the mixed stands of maize and beans (2.33 predators per 30 aphids) as compared to their occurrence in pure stands of cowpeas (0.85 predators per 30 aphids) as there were numerous aphids on beans at pre-flowering phase that supported a higher population level of coccinellids. Also, predator population was at the peak during the tussling stage of maize as they fed on the pollen grains while aphids on cowpeas co-existed mutualistically with black ants that protected them against predation. The genus Cheilomenes spp. was the most ubiquitous predator with a mean of 4.00 individuals per 30 aphids while Hippodamiavariegata was the least abundant predator species with a mean of 0.92 individuals per 30 aphids in all the agroecosystems as the Cheilomenes spp. had a faster discovery rate, range of perception, effective capture efficiency and a shorter handling time of a prey. Key words: Phenology, stands, Zea mays L., Phaseolus vulgaris L., Vignaunguiculata L. Walp, agroecosystem.
The effectiveness of coccinellids as natural enemies of aphids in maize, beans and cowpeas intercrop
(2012) Nyukuri, Robert W.; Kirui, Stella C.; Wanjala, Fred M.E.; Odhiambo, J.O.; Cheramgoi, Evelyne
Abstract: A field study was conducted in Busia district of Kenya to elucidate the dynamics of ladybirds in mixed stands of maize, beans and cowpeas to determine their efficacy as sole control measures for Aphids. Maize, beans and cowpeas were intercropped using conventional husbandry practices and the general Coccinellid quantified as follows: Colonies of four Coccinellids, starved for 12 hours to enhance feeding on Aphids were assessed. The effects of weather on the abundance of Coccinellids were also investigated and involved collection of meteorological data from the Busia District Agricultural Office (BDAO) and from Busia Farmers Training Centre (BFTC) and relating them to the abundance and predation values. The predator population was most abundant in the mixed stands of maize and beans (2.33 predators/30 Aphids) as compared to their occurrence in pure stands of cowpeas (0.85 predators/30 Aphids). The genus Cheilomenes spp. was the most ubiquitous predator with a mean of 4.00 individuals/30 Aphids while Hippodamia variegata was the least abundant predator species with a mean of 0.92 individuals/30 Aphids in all the agro-ecosystems. The larvae of Hippodamia variegata were the most bio-efficient, consuming 32.44 Aphids while their adults were the least bio-efficient, consuming 4.22 individuals for a period of 12 hours. The Coccinellids consumed more Aphids at higher aphid densities (24.05 Aphids) than at lower aphid densities (9.44 Aphids) over the same period of time. Rainfall and relative humidity had significant (F = 3.675; P < 0.05) effects on the abundance of Coccinellids. Temperature had significant (F = 3.58; P < 0.05) effect on the abundance of Coccinellids though at a lower level. Rainfall (r = -0.162) and relative humidity (r = - 0.084) were both inversely correlated with the abundance of Coccinellids. On the other hand, temperature was positively correlated (r = 0.159) with the prevalence of Coccinellids indicating that warmer and drier conditions favoured their multiplication. Key words: Efficacy, Coccinellids, Aphids, natural enemies, ecological factors, crops.
Nutrient reduction in runoff water from sugarcane farms by sedimentation method
(Environmentalist Journal, 2012-09-02) Omwoma, Solomon; Omwoyo, N.W.; Alwala, J.O.; Ongeri, David; Lagat, Sylas; Lalah, Joseph
Due to intensive use of agronomic inputs in sugarcane farming, runoff water from these farms is loaded with high concentrations of nutrients. These nutrients find their way into rivers, lakes and sinks, eutrophicating them. Reducing the levels of these nutrients in runoff water from sugarcane farms before it is discharged into sinks will help solve the problems that arise out of eutrophication. This study employed a simple sedimentation method of making depressions in canals draining runoff water from sugarcane farms and emptying them fortnightly during the rainy season and monthly during the dry season. The method was found to significantly (p ≤ 0.05) reduce water conductivity (μS/cm), turbidity (Nephelometric Turbidity Units), total phosphates, nitrate–nitrogen, potassium, calcium, magnesium, iron, copper, sodium and zinc (ppm) in the dry season from 52.89, 148.70,0.87, 3.34, 446.00, 420.00, 205.00, 12,941.00, 261.00, 398.00, and 484.00 in untreated canals to 48.33, 30.22, 0.21, 2.95, 120.00, 154.00, 98.00, 456.00, 181.00, 234.00, and 311.00 in treated canals, respectively. And in the wet season, the parameters were reduced from 261.46, 719.30, 820.00, 25.16, 654.00, 549.00, 493.00, 19,230.00, 763.00, 748.00, and 903.00 to 128.67, 365.70, 3.47, 10.12, 136.00, 187.00, 167.00, 654.00, 207.00, 321.00, and 231.00, respectively. Dissolved oxygen significantly (p ≤ 0.05) increased from 5.11 to 8.14 ppm in the dry season and from 3.82 to 7.92 ppm wet season. Acidity reduced in the wet season from pH 5.02 to 6.20. It is, therefore, recommended
Sorption and Availability of Potassium in selected Soils from Kenya: Effects of organic matter and pH on concentration of adsorbed potassium in sugarcane and maize growing zones
(Lambert Academic Publishing, 2013-01-01) Alwala, J.O.
Potassium fertilizers have been found to increase yields of food crops in soils of Kenya and the world. The availability of potassium in maize and sugarcane growing soils in Kenya is unknown and this could be causing the low crop yields. It is therefore necessary to establish the availability of soil potassium to determine its efficiency for maize and sugarcane needs with reference to regions in Kenya. The necessity of the work is to ensure optimum nutrient availability and low cost of nutrient application with high yield of maize and sugarcane. The study of the availability of potassium reserves in these areas will enable farmers to determine whether or not to apply fertilizer. The book is divided into five chapters. This study is useful to farmers who want to practice large scale production of maize and sugarcane. The farmers are able to know the effect of pH, organic matter and potassium concentration on adsorption capacity of the soils because the adsorbed potassium concentration fit to Langmuir and Freundlich isotherms and adsorption of potassium differs significantly (p≤ 0.05) with organic matter and pH.
Investigation of radiative characteristics of the Kenyan atmosphere due to aerosols using sun spectrophotometry measurements and the COART model
(Taiwan Association for Aerosol Research : Aerosol and Air Quality, 2013-01-01) Makokha, John Wanjala; Angeyo, H.K.
Variations in the radiative characteristics of aerosols can be used to quantify their effects on climate. This study evaluated the temporal-spatial variability of aerosol radiative characteristics at λ = 440 nm, λ = 675 nm, λ = 870 nm and λ = 1020 nm over the Nairobi-1°S, 36°E, Mbita-0°S, 34°E and Malindi-2°S, 40°E sites of Kenya. Aerosol optical properties from AERONET were used as inputs in the Coupled Ocean Atmosphere Radiative Transfer (COART) code to model aerosol radiative effects. The results over Nairobi showed an increase in reflectance of 2.6%, 6.7%, 7.2% and 2.4% for 2006–2007 at the specified wavelengths, respectively. Drops of 2.7%, 12.2%, 50.6% and 25.6% were noted in the same wavelengths for the 2007–2008 period. The reflectance over Mbita (0.2284) was higher than that over Nairobi (0.1396) at λ = 675 nm for 2007, due to biomass burning at site. Maritime conditions and aerosols coupled with long range transport of monsoon winds explain the higher reflectance observed over Malindi when compared to Nairobi, except for λ = 440 nm in 2008. This is as a result of aerosols from vehicular and industrial emissions that dominate the λ = 440 nm over Nairobi. The variability of downward and upward spectral irradiance measured at the surface and 12 km levels depended on the wavelength of measurement, but was temporally invariant. Upward irradiance decreased with increasing Solar Zenith Angles (SZAs) due to strong Fresnel reflection at large angles. The equality in the upwelling irradiances at the two atmospheric levels at all sites for λ = 870 nm and λ = 1020 nm was due to the near IR absorption by aerosols. The radiant flux lost in the spectral range 440–1020 nm remained relatively constant over the study sites, and thus the influence of aerosols on radiative characteristics was independent of both site and period of study.
Estimation of radiative forcing due to aerosols over selected sites in Kenya
(Kenya Meteorological Society : Journal of Meteorology and Related Sciences, 2013-01-01) Makokha, John Wanjala; Angeyo, H.K.
Variations in the radiative characteristics of aerosols can be used to quantify their effects on climate. This study evaluated the temporal-spatial variability of aerosol radiative characteristics at λ = 440 nm, λ = 675 nm, λ = 870 nm and λ = 1020 nm over the Nairobi-1°S, 36°E, Mbita-0°S, 34°E and Malindi-2°S, 40°E sites of Kenya. Aerosol optical properties from AERONET were used as inputs in the Coupled Ocean Atmosphere Radiative Transfer (COART) code to model aerosol radiative effects. The results over Nairobi showed an increase in reflectance of 2.6%, 6.7%, 7.2% and 2.4% for 2006–2007 at the specified wavelengths, respectively. Drops of 2.7%, 12.2%, 50.6% and 25.6% were noted in the same wavelengths for the 2007–2008 period. The reflectance over Mbita (0.2284) was higher than that over Nairobi (0.1396) at λ = 675 nm for 2007, due to biomass burning at site. Maritime conditions and aerosols coupled with long range transport of monsoon winds explain the higher reflectance observed over Malindi when compared to Nairobi, except for λ = 440 nm in 2008. This is as a result of aerosols from vehicular and industrial emissions that dominate the λ = 440 nm over Nairobi. The variability of downward and upward spectral irradiance measured at the surface and 12 km levels depended on the wavelength of measurement, but was temporally invariant. Upward irradiance decreased with increasing Solar Zenith Angles (SZAs) due to strong Fresnel reflection at large angles. The equality in the upwelling irradiances at the two atmospheric levels at all sites for λ = 870 nm and λ = 1020 nm was due to the near IR absorption by aerosols. The radiant flux lost in the spectral range 440–1020 nm remained relatively constant over the study sites, and thus the influence of aerosols on radiative characteristics was independent of both site and period of study.
Characterization and evaluation of repellent effect of essential oil of mangifera indica l. from Kenya
(Journal of Essential Oil Bearing Plants, 2013-03-12) Alwala, J.O.; Wanzala, W.; Inyambukho, RA.
Ethnopharmacologically, the mango has a lot of applications in life in humanhealth and ethnoveterinary medicines since ancient times. The study aimed at characterizing theessential oil of Mangifera indica L. leaves and evaluating its repellent effect on the host-seekingfemale Anopheles gambiae,the vector of African malaria. The essential oil was obtained byhydrodistillation and analyzed by gas chromatography (GC) and gas chromatography-massspectrometry (GC-MS). The repellent effect of the essential oil was evaluated using the human-baittechnique to simulate field situation. Of the 26 major hydrocarbon compounds identified, α-pineneoccurred in the largest amount (33.3 %), followed by α-phellandrene (22.6 %), Limonene (13.2 %),p-cymene (6.1 %), Heptane (3.8 %), β-pinene (2.6 %), Ledene (1.3 %), (-)-α-gurjunene (1.2 %), β-myrcene (1.1 %), γ-terpinene (1.0 %), (+)-2-carene (0.9 %) and trans (β)-caryophyllene (0.9 %) inthat order. The oil showed a significant dose-dependent repellent effect on host-seeking femaleAnopheles gambiae s.s. The oil showed a complex composition of hydrocarbon compounds andmay be richer in monoterpenes than in any other type of compounds. It showed the potential to repelmosquitoes.
Determination of tannin concentrations in african indigenous vegetables, grains and cassava roots from Emuhaya District, western Kenya
(Sciknow Publications Ltd : American Journal of Nutrition and Food Science, 2014-01-01) Wanzala, W.; Alwala, J.O.; Kiema, Francis N.
The studyevaluated tanninconcentrations in four vegetables, three grains and cassava roots as the most common foodstuffs in the diet of local communities from Emuhaya district in western Kenyaand their nutritional health implication. Plant specimens were collected from local arable farms and market centres and their identities confirmed at Maseno University herbarium. Tannincontent was evaluated using the International Phamacopoeia Method.Percent compositionof tannins in the sampled specimens were: 9.49±0.6 for rattle pod (Crotalaria brevidens(Emiroo); Family, Fabaceae), 8.38±0.3 for narrow-leaf bitter-pea(Daviesialeptophylla(Omurere); Family, Fabaceae), 2.49±0.2 for amaranth (Amaranthushybridus(Tsimboka); Family, Amaranthaceae), 0.42±0.04for black nightshade(Solanumnigrum(Lisutsa); Family, Solanaceae), 9.21±0.4 for peanut/groundnut (Arachishypogaea(Tsinjugu); Family, Fabaceae), 8.24±0.4 for sesame(Sesamumindicum(Tsinuni); Family, Pedaliaceae), 8.11±0.2 for finger millet (Eleusinecoracana(Obulee); Family, Poaceae) and 6.99±0.5 for cassava (Manihotesculenta(Emioko); Family, Euphorbiaceae). Solanumnigrumhad significantly the lowest tannin composition profile followed by A. hybridusand M. esculentain that order (P < 0.05). Interestingly, these three plants are preferred in the diet to the rest of the plants. The results provide scientific rationale for dietary exploitationof these plants bythe local communities and may lay down some groundwork for exploiting partially refined products such as peanut butter and a wide range of grades of flour for human consumption and livestock feeds. However, consumption of tannins in the diet may sometimes benecessary for optimal health but caution needs to be taken for their conflicting adverse medical-based nutritional and physiological effects.
Internal energy of a grand canonical ensemble of a mixture of helium isotopes with duo-fermion spin degeneracy
(Centre for Info Biotechnology-IJPMS, 2015-12-01) Lusamamba, Simon Mwatulo; Sakwa, Thomas W.; Odhiambo, Jared Oloo; Oketch, Vincent O.; Ochola, Alphayo
We have considered a system consisting of a mixture of helium isotopes 3He-4He interacting weakly in pairs. The partition function of the system with duo-spin and varying number of bosons and fermions is developed to bring out the superfluid properties of the system. The study focused on a Grand Canonical ensemble of 3He - 4He isotopes whose superfluid properties have been determined by distinctively singling out the duo spin component. The internal energy was established algebraically, analyzed and found out to be increasing with temperature. For high temperatures, internal energy remains constant due to particle saturation.
Sun-photometric study and multivariate analysis of aerosol optical depth variability over some representative sites of the Kenyan atmosphere
(International Journal of BioChemiPhysics,, 2015-12-01) Makokha, John Wanjala; Angeyo, H.K.; Muthama, John Nzioka
The goal of this study was to explore the temporal-spatial characteristics of aerosol optical depth (τ)over the Kenyan urban (Nairobi-1°S, 36°E), rural (Mbita-0°S, 34°E) and maritime (Malindi-2°S, 40°E) atmospheres using sun spectrophotometric measurements obtained from Aerosol Robotic Network (AERONET).AERONET measurements have been taken in Kenya since 2006 and are aimed at assessing aerosol effects on climate and improving the aerosol data base in the region. The multivariate nature of environmental measurements however allows only a limited understanding of atmospheric aerosol characteristics when univariate analysis technique is used. Temporal-spatial characteristics of atmospheric aerosol optical depth can be understood comprehensively if it is appropriately retrieved from ground-based spectrophotometric measurements and then decoupled and analyzed using multivariate analysis techniques since they can explore groups of variables simultaneously, thus providing a more meaningful insight into the temporal-spatial variability of τ is inevitable. The influence of rain and dry spells and temperature on τ at wavelengths, λ = 440 nm and λ = 1020 nm as quantified by Principal Component Analysis (PCA) ranged between 76-83 % and 7-14 %and 4-7 % respectively for all the sites. It was found out that urban heat island (over Nairobi) and local air circulation effects (over Mbita and Malindi) modulate the characteristics of aerosol optical depth over the studied sites. Spatial variability in τ as shown by Hierarchical Cluster Analysis (HCA) is independent of measurement wavelength but dependent on aerosol burden in the atmosphere for each site. The individual and coupled influence of weather parameters on atmospheric aerosols has been\ isolated and quantified and found to be site dependent.
Quantum thermodynamics of a strongly interacting bose-fermi mixture in a three-dimensional anharmonic potential
(Researchgate, 2016) Mumali, O.W.; Ayodo, Y.K.; Ndinya, B.O.; Odhiambo, J.O.
Thermodynamic properties of Bose-Fermi mixture at ultra-low temperatures were studied using perturbation theory in three Cartesian coordinates. The Hamiltonian for the mixture was developed in terms of boson-boson, boson-fermion and fermion-fermion interactions. In both first and second excited states the mixture had about 150 joules of energy at about 40 kelvins. In both first and third excited states, the mixture had energy value of about 200 joules at a temperature of about 48 kelvins. The mixture had energy value of about 240 joules at about 58 kelvins in both the second and the third excited states. The specific heat capacity versus temperature curves showed sharp turning points with peak values of specific heat capacity being 11.58J/mol/ at about 6.9 kelvins for first excited state, 7.88J/mol/ at about 13.7 kelvins for second excited state and 6.758J/mol/ at about 20.9 kelvins for third excited state. Entropy of the BF mixture in an excited state was found to increase with temperature and became constant at higher temperatures.
Effect of CuO2 plane on the thermodynamic properties of double Tl-O layered cuprate based on an interaction between cooper pair and an electron
(2016) Odhiambo, J.O.; Sakwa, T.W.; Rapando, B.W.; Ayodo, Y.K.
Electron interaction near the critical temperature is viewed as a contributor to the establishment of the energy gap which of late is projected to be a harbinger to explaining microscopic mechanism behind High temperature superconductivity. This study investigated the effects of the number of planes of CuO2 on the thermodynamic properties of double Tl-O layered compounds: Tl2Ba2CaxCuyOz (Tl22XY) High temperature superconducting cuprates due to an interaction between a Cooper Pair and an electron. The energy of interaction at the critical temperature (Tc) was seen to increase with increase in the number of CuO2 planes. The specific heat per unit mass, Sommerfeld coefficient as well as the entropy per unit mass, decreased with an increase in the number of CuO2 planes. The peak Sommerfeld coefficient temperature (T’) was noted to be approximately 0.66Tc in all considered cases of Tl22XY.
A survey of the applications and use of ethnomedicinal plants and plant products for healthcare from the ukambani region in Eastern Kenya
(IJEPP, 2016-01-01) Wanzala, W.; Syombua, Sr. Marcellina; Alwala, J.O.
The Akamba people of Kenya have a long history of ethnobotany, dating back to the pre-colonial era. Building on the Akamba’shistorical businesses involving the trade of various plants and plant products called ‘Miti,’ literally meaning plants, the Mitiare used in primary healthcare systems. Overall, the Mitilack proper documentation. Thus, the primary purpose of this paper is to record and classify the plants used by the Akamba. Non-alienating, dialogic, participatory action research (PAR) and participatory rural appraisal (PRA) approaches wereused to survery 25 women and men between the ages of 50 and 86 years old. Results indicated 200 useful medicinal plant species from 58 families, while their application methods for a wide range of ill-health conditions affecting humans, cattle and poultry were also documented. The recorded medicial conditions ranged from those that manifest clinically to those that are cultural, spiritual and psychological in nature. Management of many chronic and complicated ill-health conditions showed that the Kambaethnomedical system may practically be comparable to that of conventional medicine, particularly following an in-depth scientific studies.
Chemical composition of essential oil oftithonia diversifolia(hemsl.) a. gray from the southern slopes of Mount Elgon in western Kenya
(I J E P P, 2016-06-01) Wanzala, W.; Osundwa, E.M.; Alwala, O.J.; Gakuubi, M.M.
Ethnopharmacologically, Tithonia diversifolia has a lot of applications in the history of human life. The current study aimed at characterizing the essential oil from fresh aerial parts of T. diversifolia. The plant materials were obtained from western Kenya and oil extracted by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Compounds were identified by comparison of their mass spectra with those in Wiley NBS and NIST databases and GC retention times to those of authentic samples. The percentage yield of the essential oil of T. diversifoliawas 0.00015% w/w. The oil showed a complex composition of about 50 compounds, a mixture of monoterpenes and sesquiterpenes, 54% and 46%, respectively.Within the sub-classes of terpenes, hydrogen-carbon-containing terpenes (72%) occurred more than oxygen-containing terpenes (28%) with hydrogen-carbon-containing sesquiterpenes (38%) occurring in the highest proportion, followed by hydrogen-carbon-containing monoterpenes (34%), oxygenated monoterpenes (20%) and oxygenated sesquiterpenes (8%). Twenty-four percent of the 50 compounds and most of the monoterpenes were found in literature to have some repellence properties. Of these 50 compounds, α-pinene occurred in the largest amount (63.64%), followed by β-pinene (15.0%), iso-caryophyllene (7.62%), nerolidol (3.70%), 1-tridecanol (1.75%), limonene (1.52%), sabinene (1.00%), α-copaene (0.95%), α-gurjunene (0.56%) and cyclodecene (0.54%). With multipotential applications nature of T. diversifoliaplant and its products, these compounds may in future be useful in pharmaceutical, agricultural, food and perfumery industries
Thermodynamic properties of mercury based cuprate due to Cooper pair-electron interaction
(JMEST, 2016-07) Odhiambo, J.O.; Sakwa, T.W.; Ayodo, Y.K.; Rapando, B.W.
Interaction between electrons at the critical temperature that culminates into formation of Cooper pair holds the key in explaining cuprates high temperature superconductivity. We study the effects of the number of copper oxide planes on thermodynamic properties of Mercury based high temperature superconductivity due to an interaction between cooper pair and electrons. We noted that the energy of interaction at the critical temperature was seen to increase with increase in the number of copper oxide planes. The specific heat, Sommerfeld coefficient and the entropy per unit mass, decreased with an increase in the number of copper oxide planes. The peak Sommerfeld coefficient temperature was noted to be approximately 0.66 times critical temperature in all considered cases of mercury based cuprates.
Transformations in Kenyan science teachers’ locus of control: the influence of contextualized science and emancipated student learning
(Routledge, 2017-02-21) Anderson, D.; Nashon, N.; Namazzi, E.; Okemwa, P.; Ombogo, P.; Ooko, S.; Beru, Festus K.
This study investigated Kenyan science teachers’ pedagogical transformations, which manifested as they enacted and experienced a reformed contextualized science curriculum in which students’ learning experiences were critical catalysts of teacher change. Twelve high school teachers voluntarily participated in the study and were interviewed about their pedagogical transformations following their enactment of a reformed contextualized science curriculum. The outcomes demonstrated that students’ emancipated behaviours, learning and performance, qualitatively influenced teacher change and pedagogical reform. Specifically, changes in students, as a result of the ways the science curriculum was implemented, resulted in epiphanies and dilemmas for teachers who subsequently resolved to surrender their tightly held pedagogical control (locus of control) for the betterment of the learning environment and their sense of professional satisfaction.
Aerosol optical depth and precipitation rate projections over east africa utilizing self organizing map
(The International Journal Of Science & Technoledge, 2017-03-01) Makokha, John Wanjala; Angeyo, H.K.; Muthama, John Nzioka
Assessment of future aerosols impacts on both regional and global climate change requires a comprehensive projection tool that reliably provides information on aerosol evolution characteristics with high fidelity. In the current study, we propose an algorithm based on Self-Organizing Map (SOM) and Community Atmosphere Model 4 (CAM4) for long term Aerosol Optical Depth (AOD) and Precipitation Rate (PR) projections over East Africa. To start with, AOD and PR retrievals from Moderate Resolution Imaging Spectroradiometer (MODIS) and Tropical Rainfall Measurement Mission (TRMM) respectively were cross validated with simulation from CAM4 so as to assess the uncertainty between the measured and simulated retrievals from 2000 to 2014.The error analysis between CAM4 simulations and MODIS measurements (from 2000 to 2014)shows a close match where R2 varies from 0.58 to 0.83 with a corresponding RMSE of between 0.014 and 0.065 (for AOD). Likewise, the uncertainty between simulate and measured PR from CAM4 and TRMM showed an estimated R2 to range between 0.40 and 0.78 while the RMSE varied from 0.021 to 0.091 in the same period and study sites. Based on proposed SOM algorithm and simulated CAM4 retrievals over each study site, an increase of between 1.34-2.43 % for AOD and a decrease of between 1.03-1.98 % in PR are projected over the region by 2030.

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