Department of Science, Technology and Engineering
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Item The Specific Heat Of Boson-Fermion Pair Condensate In Optimally-Doped Cuprates(Journal of Multidisciplinary Engineering Science and Technology, 2021-12-12) Mukubwa, Abel; Makhokha, John; Masinde, FredRecent studies have shown that the interaction between a finite momentum Cooperpair boson and a fermion supports superconductivity in cuprates. Specifically, the occurrence of a superconducting energy gap in cuprates is defined by the collective excitation of boson-fermion pair condensates (BFPC) above the ground state. The ground state energy of BFPC in these materials show dependence on single-fermion spins. We study the specific heat of a BFPC in high temperature cuprates based on the ground state energy which represents the total internal energy of the system. The model results are in close proximity with the empirical findings. For instance, the specific heat of the model in Y123 is determined as 𝟏𝟏𝟖. 𝟗 𝐉𝐦𝐨𝐥−𝟏𝐊−𝟏, which close to the measured value of 𝟏𝟐𝟕. 𝟖 𝐉𝐦𝐨𝐥−𝟏𝐊−𝟏.Item DFT calculations of elastic, electronic and thermal properties of TiB2Mo(Oxford Open Materials Science, 2022-02-02) Wafula, Job; Manyali, George; Makhokha, JohnCeramics are materials with good mechanical properties; however, low fracture toughness, intrinsic brittleness and poor resistance against oxidation at high temperatures are challenges limiting their applications. TiB2Mo is a ceramic material whose all elastic properties have not been calculated. In this study, we investigated the elastic, electronic and thermal properties of TiB2Mo structure using first principles calculations. All first principles calculations were based on the density functional theory as implemented in Quantum ESPRESSO code with the help of Thermo-pw as a post-processing code. Obtained lattice parameters of TiB2Mo structure were in good agreement with other previous theoretical studies. TiB2Mo structure was found to be mechanically and dynamically stable at ground state conditions. The results also show that TiB2Mo is brittle, anisotropic and metallic in nature. Based on the calculated Vicker’s hardness Hv, we noted that TiB2Mo is classified as a hard material with fracture toughness of above 7MPam0:5; therefore, it is a promising ultra-high temperature ceramic.Item A technological infrastructure assessment framework for telemedicine adoption in Kenyan level four hospitals(KIBU, 2019-06-12) Randu, Karisa K.; Nambiro, Alice; Kilwake, JumaTelemedicine is the use of telecommunication and information technologies in order to provide clinical health care at a distance, it helps eliminate distance barriers and can improve access to medical services that would often not be consistently available in distant rural communities, many health professionals leave Kenya to find posts abroad, this results to a severe shortage of medical workers across the country. According to the World Health Organization, Kenya has just one doctor and only 12 nurses/midwives for every 10,000 people.Some of the level four hospitals lack specialized doctors therefore they are being forced to employ nurses who come in to assist in treatment of the patient. The use of telemedicine can sound costly but in the current environment of shortage of healthcare professionals, greater incidence of chronic conditions and rising healthcare costs may call for further research and telemedicine can come in to assist solving this problem. The aim of this paper is to establish the current status of telemedicine in level four hospitals and assess their technological infrastructure in order to identify the challenges that might be faced by these hospitals upon adopting telemedicine. The paper accomplishes its objectives by conducting an online review of the assessment of technological infrastructure of Kenyan level four hospitals, the telemedicine status and challenges faced by telemedicine adoption. It found that there is Lack of adequate technological infrastructure, lack of a change management plan, no business model, limited buy-in from practitioners, high staff turnover, limited e-Readiness, low bandwidth and inappropriate software. The findings of this paper can help improve the telemedicine adoption status which in turn improves the health of the community and population living around these hospitals by bringing more services, medical professionals sharing ideas and more importantly a tool to save a life.Item Contextualized science teaching and student performance: the case of a Kenyan girls science class(Instituto de Relaciones Internacionales" Daza de Valdes", 2017-06) Ooko, Selline; Beru, Festus K.; Nashon, Samson M.; Anderson, David; Namazzi, ElizabethThis paper is about a case study that investigated the impact of contextualized science teaching and learning onperformance of a Form three (Grade 11) class in one of Kenya’s girls high schools. The class experienced nine weeks ofcontextualized science learning. This involved a full day visit toJua Kaliwhere they interacted with artisans. ‘‘Jua Kali’’ is asmall-scale manufacturing and technology-based service sector where artisans manufacture equipment and otherhousehold items that are ubiquitous in everyday Kenyan culture. The visit was followed by organized classroom-basedgroup discussions about what they had learnt and considered most relevant and meaningful. Following this highlyengaging student learning discourse, their creativity and innovative abilities in science improved tremendously as reflectedin the quality of class presentations and participation in the National Science Congress. Moreover, the school’sperformance in the Kenya Certificate of Secondary Education (KCSE): a final national exam at the end of Form 4(Grade 12) improved from a mean of 9.3 in the previous year to 10.4 in the intervention year (p = 0.022). This was furtherattributable to significant improvement in all science subjects: biology, chemistry, physics and mathematics. Besides thecritical insights about theJua Kali’srichness in scientific phenomena, there is also great potential for contextualized scienceexperience to enhance students’ deeper understanding of science.Item 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.Item 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.Item 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, JosephDue 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, recommendedItem 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.Item 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.Item 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.Item 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 industriesItem Thermodynamic properties of an interaction between cooper pairs and electrons in bismuth based cuprate superconductivity(KIBU, 2017-06-15) Odhiambo, J.O.; Sakwa, W.T.; Ayodo, K.Y.; Makokha, J.W.A theoretical study considering Bi2201, Bi2212 and Bi2223 bismuth based cuprates whose critical Temperatures (TC) are 20K, 95K and 110K with one, two and three CuO2 planes respectively; based on an interaction of Cooper pair and an electron in Bismuth based cuprates oxide shows that there is a direct correlation between energy of interaction and the number of CuO2 planes at the TC. The specific heat for a mole of Bismuth based cuprates at TC was found to be 7.471×10 −24J𝐾 −1 regardless of the number of CuO2 planes; though the specific heat per unit mass, Sommerfeld coefficient as well as entropy per unit mass decreased with an increase in the number of CuO2 planes. The entropy of a mole of Bismuth based cuprates at TC was found to be 5.603×10−24𝐽𝐾−1 irrespective of the TC or mass. The peak Sommerfeld coefficient temperature was noted to occur at the ratio T/TC=0.66 in the bismuth based cuprates.Item Seasonal variability in aerosol microphysical properties over selected rural, urban and maritime sites in Kenya(2018) Khamala, Geoffrey W.; Odhiambo, J.O.; Makokha, John W.Atmospheric aerosols are posing a great threat to the already stressed climate with the effects being felt more on African continent. Their presence and interaction with the clouds contribute to the strongest uncertainty in aerosol characteristics and Earth’s energy budget hence; calling for a long term assessment to be done. The present study analyses long term spatiotemporal microphysical aerosol characteristics (namely: effective radius (eff r) and surface-area concentration), using AErosolROboticNETwork (AERONET) framework over Kenyan urban atmosphere (Nairobi-1 S, 36 E), rural atmosphere (ICIPE-Mbita-0 S, 34 E) and maritime atmosphere (CRPSM-Malindi-2 S, 40 E). AERONET framework was used due to its availability over the selected sites; it is also located in sites that provided contrasting aerosols type, source and characteristics and due to its synergism with other frameworks. The findings indicated a spatial and temporal variability in microphysical properties over CRPSM-Malindi, Nairobi and ICIPE-Mbita. CRPSM-Malindi is dominated with coarse aerosols in all seasons while Nairobi with coarse mode in the DJF and MAM seasons. ICIPE-Mbita is on the other hand dominated with fine aerosols in all season. In terms of size distribution, the three AERONET sites displayed a bimodal distribution inflecting at 0.44 µm and fine mode radius of 0.15 µm while CRPSM-Malindi recorded a coarse mode of 3.86 µm and Nairobi and ICIPE-Mbita with 5.06 µm. The coarse aerosols have a higher concentration than the fine aerosols in all AERONET sites because of aerosol coagulation and dominance of certain type of aerosols that are coarse.Item Spatial-temporal characterization of atmospheric aerosols via airborne spectral imaging and growing hierarchical self-organizing maps(Scientific Research Publishing, 2018-06-25) Makokha, John W.; Odhiambo, J.O.Neural network analysis based on Growing Hierarchical Self-Organizing Map (GHSOM) is used to examine Spatial-Temporal characteristics in Aerosol Optical Depth (AOD), Ångström Exponent (ÅE) and Precipitation Rate (PR) over selected East African sites from 2000 to 2014. The selected sites of study are Nairobi (1˚S, 36˚E), Mbita (0˚S, 34˚E), Mau Forest (0.0˚ - 0.6˚S; 35.1˚E - 35.7˚E), Malindi (2˚S, 40˚E), Mount Kilimanjaro (3˚S, 37˚E) and Kampala (0˚N, 32.1˚E). GHSOM analysis reveals a marked spatial variability in AOD and ÅE that is associated to changing PR, urban heat islands, diffusion, direct emission, hygroscopic growth and their scavenging from the atmosphere specific to each site. Furthermore, spatial variability in AOD, ÅE and PR is distinct since each variable corresponds to a unique level of classification. On the other hand, GHSOM algorithm efficiently discriminated by means of clustering between AOD, ÅE and PR during Long and Short rain spells and dry spell over each variable emphasizing their temporal evolution. The utilization of GHSOM therefore confirms the fact that regional aerosol characteristics are highly variable be it spatially or temporally and as well modulated by PR received over each variable.Item Optical characterization of atmospheric aerosols via airborne spectral imaging and self-organizing map for climate change diagnostics(2018-08-03) Makokha, John W.; Odhiambo, J.O.Self-Organizing Map (SOM) analysis is used to perform optical characterization of both Aerosol Optical Depth (AOD) and Ångström Exponent (ÅE) retrieved from Moderate-resolution Imaging Spectroradiometer (MODIS) in relation to Precipitation Rate (PR) from Tropical Rainfall Measurement Mission (TRMM) over selected East African sites from 2000 to 2014 and further diagnose climate change over the region if any. SOM reveals a marked spatial variability in AOD and ÅE that is associated to changing aerosol transport, urban heat islands, diffusion, direct emission, hygroscopic growth and their scavenging from the atmosphere specific to each site. Temporally, all sites except Mbita and Kampala indicate two clusters in AOD that are associated to prevailing dry and wet seasons over East Africa. Moreover, all sites except Mbita and Mount Kilimanjaro show two clusters in ÅE that are related to aerosol mode of generation and composition over the region. The single cluster in AOD and ÅE over Mbita indicate that aerosol characteristics over the site are influenced by biomass burning and local air circulation rather than the monsoon precipitation throughout the study period.Item 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.Item 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.Item 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.Item 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.Item 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.