School of Science, Technology and Engineering

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3rd International Conference on Food chemistry and nutrition
(Journal of Experimental Food Chemistry, 2018-05-16) Mbakaya, Charles
Assessment of iron status among preschool children (6 to 59 months) with and without malaria in Western Province, Kenya
(Pan African Medical Journal, 2015-05-05) Mbakaya, Charles; Kisiangan, Isaac; Makokha, Anzelimo; Magu, Dennis
Iron deficiency is a major public health concern. Globally, iron deficiency ranks number 9 and is responsible for about 60% of all anemia cases among preschool children. In Africa iron deficiency is 43-52% while in Kenya, children under 5 years constitute the largest burden with 69% of them being deficient. There is limited iron deficiency data in Kenya. This study determined haemoglobin levels, serum ferritin levels, nutritional status and P.falciparum malaria infection in preschool children. Methods: A household cross sectional study was undertaken among 125 preschoolers in Western province, drawn from 37 clusters. Systematic random sampling was used for sample selection. Data was collected using pretested structured questionnaires, entered in Microsoft package. Data analysis was done in Statistical package for social science (SPSS) version 20 using bivariate and multivariate logistic regression and differences were considered significant at P < 0.05. Results: The prevalence of iron deficiency (Serum ferritin <12mg/l), anaemia (Hb<110g/l) and plasmodium falciparum malaria were 20.8%, 25% and 6.8% respectively. There was a significant association between iron deficiency and anaemia (OR=3.43, 95% CI: 1.33-8.84, p=0.008). A preschool child with anaemia was 3.43 times likely to be iron deficient compared to a preschool child who was not anaemic. Conclusion: Iron deficiency, anaemia and plasmodium falciparum malaria was prevalent among preschool children. The findings revealed a significant association between iron deficiency and anaemia. Therefore effective interventions to improve iron status will have large health benefits by greatly reducing anaemia in preschool children.
Assessment of microbiological contaminants in community water sources in lower Nyakach Division, Kisumu County, Kenya
(Elixir, 2014-09-04) Olal, B.A; Owuor, J. B. Okeyo; Tsingalia HM; Odipo Osano
The importance of water as a vehicle for spreading diseases has long been recognized and many studies have demonstrated the relationship between illness and deficiencies in water supply and sanitation. This study was conducted between October 2008 and July 2009, to determine microbiological water contaminants and related human health problems in community water sources in Lower Nyakach division, Kisumu County. Water samples were collected in selected water points, analyzed using membrane filter technique and their level of microbiological contamination determined using Escherichia coli type I as bio-indicator. Household level surveys and key informant interviews were conducted and secondary data obtained from Pap-Onditi district hospital on cases of environmental and human health risks associated with water contamination. Data from field samples and survey were analyzed usingthe Statistical Package for Social Sciences. Multiple comparisons between sites were made by Analysis of Variance (ANOVA) and the student t-test. Statistical significance was assessed at p ≤ 0.05. The mean counts for faecal coliforms were lower than that of total coliforms in all samples in both dry and rainy seasons although the mean counts total coliforms were higher during the rainy season than the dry season. Water samples from water impoundments showed significant differencesin total coliforms compared to recommended WHO levels and no significant differences for faecal coliforms (α = 0.05). Water samples from shallow wells showed significance difference for faecal coliforms between three sampling sites (Pap-Onditi, Urudi and Bonde). From the survey and hospital findings typhoid fever and amoebic dysentery were the most common water-borne diseases in the study area. Faecal contaminated water possesses high human health risks which are responsible for the reported increased water-borne diseases. The study concludes that total and faecal coliforms are important parameters in monitoring faecal contamination and water quality in the area. Most of the community water sources are seasonal and largely contaminated. Consequently, frequent monitoring of water quality and levels of contaminants using total and faecal coliforms is recommended at common water points to curb potential health related risks.
Assessment of temporal primary production in tropical inland swamp wetlands of Uasin Gishu county, Kenya
(2018-07-03) Onkware, Augustino; Mulei, Josephine M.; Otieno, Donald F.
Wetlands are highly productive ecosystems offering valuable ecosystem and socio-economic services. Worldwide they are threatened by encroachment due to increasing human population. Limited research has been done on the integrity of the ecosystems and their benefits to the surrounding communities in Uasin Gishu County, Kenya. The study assessed the spatial variations in the physicochemical quality of water and soil and plant production in four freshwater swamps of Uasin Gishu County. Physico-chemical properties data was collected at an interval of one month for one year while that on nutrients was collected at an interval of three months for one year. Primary production was assessed using 0.25m2 quadrats laid systematically along transects at peak biomass. All data was subjected to analysis of variance test and multiple relationships existing between biomass and physicochemical parameters were tested using principal component analysis. Significant (P < 0.05) spatial variations in the physico-chemical properties and plant biomass were recorded. Plant biomass was mainly influenced by DO, TN, TP, Fe and the pH of the water and Na concentration in the soil. Physicochemical attributes vary significantly in the swamps and production is high despite their small size. Their protection and conservation should be considered.
Assessment of temporal primary production in tropical inland swamp wetlands of Uasin Gishu County, Kenya
(J. Wetlands Biodiversity, 2018-07-03) Josephine M. Mulei; Onkware, Augustino; Donald F. Otieno
Wetlands are highly productive ecosystems offering valuable ecosystem and socio-economic services. Worldwide they are threatened by encroachment due to increasing human population. Limited research has been done on the integrity of the ecosystems and their benefits to the surrounding communities in Uasin Gishu County, Kenya. The study assessed the spatial variations in the physicochemical quality of water and soil and plant production in four freshwater swamps of Uasin Gishu County. Physico-chemical properties data was collected at an interval of one month for one year while that on nutrients was collected at an interval of three months for one year. Primary production was assessed using 0.25m2 quadrats laid systematically along transects at peak biomass. All data was subjected to analysis of variance test and multiple relationships existing between biomass and physicochemical parameters were tested using principal component analysis. Significant (P < 0.05) spatial variations in the physico-chemical properties and plant biomass were recorded. Plant biomass was mainly influenced by DO, TN, TP, Fe and the pH of the water and Na concentration in the soil. Physicochemical attributes vary significantly in the swamps and production is high despite their small size. Their protection and conservation should be considered.
Assessment of the Impact of Anthropogenic Activities on the Drinking Water Qualities of Boreholes/Shallows Well Water in Huruma Estate -Eldoret, Kenya
(Journal of Environment and Earth Science, 2016) Olal, Francis Ongachi; Nyamolo, Moses
The objective of this research was to investigate the drinking water qualities of boreholes/shallows well water used by inhabitants of Huruma –Eldoret , by comparing the chemical, physical and bacteriological qualities with WHO standards. Samples were collected in the dry season in the months of January and February, 2014 and analysed for pH, Turbidity, TDS, Conductivity, Total Hardness, Chloride, Nitrate, Phosphate, Calcium, Magnesium, Lead, Zinc, Total Iron, Copper, Manganese, Cadmium, Total Chromium, Total Coliform, Feacal Coliform and E-coli. Standard methods were adopted for field and laboratory studies. Results of the comparisons from the four sampled stations showed that the water was not acidic as the pH was within acceptable limits. The turbidity level was high in three of the sampled stations with the highest in Lutheran church (55.0 NTU). The metals were within the safe limits. The heavy metals investigated were within tolerable limits of WHO standards with the exception of lead and total iron. Lead and total iron were detected in all the sampled stations butexceeded tolerable limits in Bondeni and Lutheran church. The Total coliform exceeded the tolerable limits for drinking water. However the hardness levels were within tolerable limits. These results showed that the borehole/well water from Huruma estate is contaminated with some pollutants entering the water table. The borehole water should therefore be protected and treated before consumption. There is need for periodic monitoring of water samples from boreholes/wells sources to ascertain their qualities.
Assessment of the Impact of Urban Runoff from Migor i Town on the Concentration Levels of Selected Heavy Metals i n Migori River, Kenya
(Journal of Environment and Earth Science, 2015) Olal, Francis Ongachi
Water pollution and decreasing water quality is a major threat to water resources in urban set ups in the developing world. The key culprits include; agricultural runoff, untreated industrial and domestic wastewater, storm water and urban runoff. Migori is a rapidly growing city in Kenya with various land uses including crop and animal farming, industries, municipal markets, and commercial and residential set ups. The large volumes of urban runoffs generated in the town and its environs wash large pollutant loads into Migori River which is the main source of water in the region. This study investigated the effect of urban runoff from Migori town and its environs on the water quality of Migori River in terms of selected heavy metals. Water samples were collected from six established sampling stations along the river for six months (in wet and dry seasons). The water quality values were summarized as mean ± SE. Results indicated continued adverse impacts on the water quality of Migori River by urban runoffs. Water quality impairment in the river increased downstream – towards the town. Lead and nickel concentration levels are way above the WHO recommended guidelines for surface waters. Thus the river water poses serious risks to humans, animals and aquatic life. There is need for public awar eness regarding the pollution problems and the consequences arising thereof in Migori River. There is also need for a study cataloguing the different chemicals used by d ifferent factories within Migori town. This will hopefully establish the definite sources of the heavy metals and nutrients and control their concentrations before they become too high andharmful to the ecosystem. Keywords: Urban run-off, Migori, water quality, pollution
Assessment of the Impact of Urban Runoff from Migori Town on the Concentration Levels of Selected Heavy Metals in Migori River, Kenya
(Journal of Environment and Earth Science, 2015-10) Olal, Francis Ongachi
Water pollution and decreasing water quality is a major threat to water resources in urban set ups in the developing world. The key culprits include; agricultural runoff, untreated industrial and domestic wastewater, storm water and urban runoff. Migori is a rapidly growing city in Kenya with various land uses including crop and animal farming, industries, municipal markets, and commercial and residential set ups. The large volumes of urban runoffs generated in the town and its environs wash large pollutant loads into Migori River which is the main source of water in the region. This study investigated the effect of urban runoff from Migori town and its environs on the water quality of Migori River in terms of selected heavy metals. Water samples were collected from six established sampling stations along the river for six months (in wet and dry seasons). The water quality values were summarized as mean ± SE. Results indicated continued adverse impacts on the water quality of Migori River by urban runoffs. Water quality impairment in the river increased downstream – towards the town. Lead and nickel concentration levels are way above the WHO recommended guidelines for surface waters. Thus the river water poses serious risks to humans, animals and aquatic life. There is need for public awareness regarding the pollution problems and the consequences arising thereof in Migori River. There is also need for a study cataloguing the different chemicals used by different factories within Migori town. This will hopefully establish the definite sources of the heavy metals and nutrients and control their concentrations before they become too high and harmful to the ecosystem
Biogas enhancement using iron oxide nanoparticles and multi-wall carbon nanotubes
(International Journal of Chemical, Molecular, Nuclear, Materials and Metalurgical Engineering, 2016) Ambuchi, John Justo; Zhang, Zhaohan; Feng, Yujie
Biosorption of Selected Heavy Metals Using Green Algae, Spirogyra Species
(Journal of Natural Sciences Research, 2016-07) Olal, Francis Ongachi
Biosorption studies were conducted to determine the adsorption parameters (pH, contact time and adsorption capacity) of cadmium, chromium, copper and lead in model aqueous solutions using green algae, spirogyra species. pH was optimized for each heavy metal. The optimum pH values were found to be 5.5, 5.8, 5.9 and 5.0 for cadmium, chromium, copper and lead, respectively. The adsorption process was second order and fitted the Langmuir isotherm better than the Freundlich. Adsorption capacities were found to be 22.52, 38.19, 35.59 and 94.34 mg/g for cadmium, chromium, copper and lead, respectively. The biosorption process was rapid with contact times of 15 minutes for cadmium, 40 minutes for chromium and copper and 50 minutes for lead. The optimum initial concentrations for metal adsorption ranged from 500 - 700 µg/mL. Adsorption kinetics of the metals on green algae were also investigated. The experimental data was tested for biosorption kinetics using first and second order kinetic models and was found to follow second order kinetics. The concentration of the selected metals was determined in algae and in the parent water. The results in both samples by ICP – OES were 1.81 ± 0.11, 64.33 ± 0.35, 17.14 ± 0.155 and 12.08 ± 1.80 µg/L in water and 2.30 ± 0.09, 12.17 ± 0.20, 25.61 ± 0.74 and 60.50 ± 1.57 µg/g for cadmium, chromium, copper and lead in algae, respectively. The average concentration factors were Cd (2547.01), Cr (367.02), Cu (1843.59) and Pb (7154.95). Little correlation was found between the heavy metal concentration in parent water and in algae from the same water (R ≤ 0.32). The concentration of the acid-leached metal fraction from the algal surface, correlated well with the total metal taken up by the algae, (0.55 ≤ R ≤ 0.94). This work demonstrates the potential of green algae as both a biosorbent and bioindicator of water pollution by the selected heavy metals
Carpet characteristics of eichhornia crassipes [mart.] solms (water hyacinth) in the winam gulf (lake victoria, kenya)
(2017-07-31) Otieno, Wagai Samuel; Opande, George; Onyango, Charles; Musyimi, David
The occurrence and spread of the water hyacinth (Eichhornia crassipes [Mart.] Solms), in the Winam gulf has created numerous attributes to the human population that live around the lake, thereby making its control a priority. Navigation within the lake is a major economic activity that has been greatly affected. Before this study, little was known about the characteristics of these weed carpets, and specifically the weight that a healthy inter-connected or entangled carpet can support before it was able to sink or even get submerged. Can a light herbivore or human stranded in the lake walk on a healthy carpet to safety?. In order to better understand these unknown, a study was initiated at five locations (i.e; Dunga beach, Kisumu pier, Kusa, Kobala and Kendu bay) within the lake that appeared to contain healthy dense carpets. Carpet connectivity, mat buoyancy, distribution of mass, biomass density, rhizome length and population density were calculated. Carpet connectivity was determined as the difference in pressure when weights were added on a mesh wire measuring 0.434m2 until the carpet submerged and the pressure on the same carpet that was required to submerge it after a complete disconnection. Standing population density was determined by counting the number of plants found within quadrants measuring 1 m2; while biomass density was determined when oven dried plant materials collected from quadrants measuring 1 m2 was weighed. Plant mass and rhizome length measurements were correlated, while population density was correlated to biomass density. These observations show that water hyacinth distribution in the Winam gulf is seasonal and adopts residence in secluded bays, carpets measuring 0,434m2 in size that have a connectivity of 288.4 Pa (pascals) are able to support a weight of only 12.6 kg, with any additional weight causing them to submerge. Distribution of mass was normal except in locations that are subjected to external factors
Carpet characteristics of eichhornia crassipes [mart.] solms (water hyacinth) in the Winam gulf (lake victoria, Kenya)
(Journal of Asian Scientific Research, 2017) Opande, George T.; Otieno, Wagai Samuel; Onyango, J. Charles; Musyimi, David M.
The occurrence and spread of the water hyacinth (Eichhornia crassipes [Mart.] Solms), in the Winam gulf has created numerous attributes to the human population that live around the lake, thereby making its control a priority. Navigation within the lake is a major economic activity that has been greatly affected. Before this study, little was known about the characteristics of these weed carpets, and specifically the weight that a healthy inter-connected or entangled carpet can support before it was able to sink or even get submerged. Can a light herbivore or human stranded in the lake walk on a healthy carpet to safety?. In order to better understand these unknown, a study was initiated at five locations (i.e; Dunga beach, Kisumu pier, Kusa, Kobala and Kendu bay) within the lake that appeared to contain healthy dense carpets. Carpet connectivity, mat buoyancy, distribution of mass, biomass density, rhizome length and population density were calculated. Carpet connectivity was determined as the difference in pressure when weights were added on a mesh wire measuring 0.434m2 until the carpet submerged and the pressure on the same carpet that was required to submerge it after a complete disconnection. Standing population density was determined by counting the number of plants found within quadrants measuring 1 m2; while biomass density was determined when oven dried plant materials collected from quadrants measuring 1 m2 was weighed. Plant mass and rhizome length measurements were correlated, while population density was correlated to biomass density. These observations show that water hyacinth distribution in the Winam gulf is seasonal and adopts residence in secluded bays, carpets measuring 0,434m2 in size that have a connectivity of 288.4 Pa (pascals) are able to support a weight of only 12.6 kg, with any additional weight causing them to submerge. Distribution of mass was normal except in locations that are subjected to external factors.
Cascade degradation of organic matters in brewery wastewater using a continuous stirred microbial electrochemical reactor and analysis of microbial communities
(Scientific Reports, 2016) Wang, Haiman; Qu, Youpeng; Li, Da; Ambuchi, John Justo; He, Weihua; Zhou, Xiangtong; Liu, Jia; Feng, Yujie
A continuous stirred microbial electrochemical reactor (CSMER), comprising of a complete mixing zone (CMZ) and microbial electrochemical zone (MEZ), was used for brewery wastewater treatment. The system realized 75.4±5.7% of TCOD and 64.9±4.9% of TSS when fed with brewery wastewater concomitantly achieving an average maximum power density of 304±31m W m−2. Cascade utilization of organic matters made the CSMER remove a wider range of substrates compared with a continuous stirred tank reactor (CSTR), in which process 79.1±5.6% of soluble protein and 86.6±2.2% of soluble carbohydrates were degraded by anaerobic digestion in the CMZ and short-chain volatile fatty acids were further decomposed and generated current in the MEZ. Co-existence of fermentative bacteria (Clostridium and Bacteroides, 19.7% and 5.0%), acetogenic bacteria (Syntrophobacter, 20.8%), methanogenic archaea (Methanosaeta and Methanobacterium, 40.3% and 38.4%) and exoelectrogens (Geobacter, 12.4%) as well as a clear spatial distribution and syntrophic interaction among them contributed to the cascade degradation process in CSMER. The CSMER shows great promise for practical wastewater treatment application due to high pre-hydrolysis and acidification rate, high energy recovery and low capital cost
Cell membrane integrity, callose accumulation, and root growth in aluminum-stressed sorghum seedlings
(2015-08-19) Gudu, Samuel; Onkware, Augustino; Emily Jepkosgei Too; Beatrice Ang’iyo Were; Anders S. Carlsson; Mulatu Geleta; T. Bryngelsson
Aluminum stress usually reduces plant root growth due to the accumulation of Al in specific zones of the root apex. The objectives of this study were to determine the localization of Al in the root apex of Sorghum bicolor (L.) Moech. and its effects on membrane integrity, callose accumulation, and root growth in selected cultivars. Seedlings were grown in a nutrient solution containing 0, 27, or 39 μM Al3+ for 24, 48, and 120 h. The Al stress significantly reduced root growth, especially after 48 and 120 h of exposure. A higher Al accumulation, determined by fluorescence microscopy after staining with a Morin dye, occurred in the root extension zone of the sensitive cultivar than in the tolerant cultivar. The membrane damage and callose accumulation were also higher in the sensitive than resistant cultivar. It was concluded that the Al stress significantly reduced root growth through the accumulation of Al in the root extension zone, callose accumulation, and impairment of plasma membrane integrity.
Cell membrane integrity, callose accumulation, and root growth in aluminum-stressed sorghum seedlings
(2015-08-21) Emily Jepkosgei Too; Beatrice Ang’iyo Were; Onkware, Augustino; Anders S. Carlsson; Mulatu Geleta; Gudu, Samuel; T. Bryngelsson
Aluminum stress usually reduces plant root growth due to the accumulation of Al in specific zones of the root apex. The objectives of this study were to determine the localization of Al in the root apex of Sorghum bicolor (L.) Moech. and its effects on membrane integrity, callose accumulation, and root growth in selected cultivars. Seedlings were grown in a nutrient solution containing 0, 27, or 39 μM Al3+ for 24, 48, and 120 h. The Al stress significantly reduced root growth, especially after 48 and 120 h of exposure. A higher Al accumulation, determined by fluorescence microscopy after staining with a Morin dye, occurred in the root extension zone of the sensitive cultivar than in the tolerant cultivar. The membrane damage and callose accumulation were also higher in the sensitive than resistant cultivar. It was concluded that the Al stress significantly reduced root growth through the accumulation of Al in the root extension zone, callose accumulation, and impairment of plasma membrane integrity.
Changes in population characteristics and diet of Nile tilapia Oreochromis niloticus (L.) from Nyanza Gulf of Lake Victoria, Kenya: what are the management options?
(Tylor&Francis, 2007-11-26) Owuor, J.B. Okeyo; M. Muchiri; M. van der Knaap; I. G. Cowx
Length frequency data collected from 1998 to 2001 from commercial landings was used to estimate asymptotic length (L∞), growth coefficient (K), mortality (Z, F, M), growth performance index (φ ) and exploitation rate (E) of Oreochromis niloticus from the Nyanza Gulf of Lake Victoria, Kenya. Studies on the diet of O. niloticus collected by demersal trawl and seining between 1998 and 2000 were also conducted. Length frequency data were analyzed using the FISAT software (an FAO-ICLARM Stock Assessment Tool package). The L∞ had a mean value (±S.D) of 58.78 ± 2.42 cm TL, K of 0.59 ± 0.05 yr−1, Z of 2.16 ± 0.40 yr−1, M of 1.00 ± 0.06 yr−1, F of 1.12 ± 0.34 yr−1, E of 0.48 ± 0.11 and φ of 3.31 ± 0.04. Length at first entry into the fishery (L50) was observed at 26.18 ± 12.50 cm TL. Recruitment occurred throughout the year, with two peaks corresponding with the rainy seasons. A comparison with previous studies in the gulf indicates that O. niloticus is now caught at a smaller mean size, whereas K, Z, and M have increased. Fish appeared to become sexually mature at a smaller size. Nile tilapia originally known to be herbivorous, feeding mostly on algae, has diversified its diet to include insects, fish, algae and plant materials, all being important food items. The changes in population characteristics and diet of O. niloticus are discussed in context of changes occurring in the lake and its surroundings.
Clinical nurses’ perspective of cancer pain management of adult patients at Garissa county, Kenya
(Journal of Health, Medicine and Nursing, 2018) Elmi, Mohamed; Too, Wesley; Mwenda, Catherine; Affey, Fatuma
Purpose: Cancer pain is inadequately assessed and managed in Kenya. Despite the development of WHO analgesic ladder since 1986 with the effective response of 80%- 90%, cancer pain at Garissa County Referral Hospital (GCRH) remains inadequately managed. The purpose of this study was to determine the clinical nurses’ perspective of cancer pain management of adult patients at GCRH. Methods and Material: A total of 84 clinical nurses were administered with questionnaires to assess their knowledge on assessment and management of cancer pain based on utilisation of WHO analgesic ladder. Clinical nurses from various departments were purposively stratified and recruited using simple random sampling. Hospital based 94 cancer patients were also assessed for their frequency and level of pain management using MBPI (Modified Brief Pain Inventory). Cancer patients from outpatient and inpatient, aged 18 years and above, present during the study period of May 18th to November 17th were included in the study. Result: Majority of Clinical nurses 54 (64.3%) had a diploma level of training, and 37 (44%) had working experience of 1-3years. A total of 81% indicated they had no training on cancer pain management and 83.2% of them reported they had not utilised WHO analgesic ladder for pain management. Majority 78 % (66) indicated they had no tool for pain assessment and 81.9% (77) of cancer patients incorrectly utilised WHO analgesic ladder. Mean age of cancer patients was 50years, composed of 42(44.7%) male and 52 (55.3%) female. Prevalence of cancer pain was 78% with majority reporting moderate to severe pain. A total of 91% male and 70% female were undertreated with PIM of (p value < 0.05). Majority of them 65% (61) and 77.6% (73) considered alternative therapy of Quran and Somali herbs respectively for pain management. Unique contribution to theory, practice and policy: This study found a high prevalence of cancer pain, knowledge deficit among clinical nurses with a negative attitude and suboptimal cancer pain management. Thus recommend the capacity building of clinical nurses’ knowledge and review of the curriculum of nursing training. Cultural sensitive and innovative strategy for cancer pain management at GCRH is also encouraged.
Collaboration between developing and developed countries and between developing countries in occupational health research and surveillance
(The Scandinavian Journal of Work, Environment & Health, the Finnish Institute of Occupational Health, the Danish National Research Centre for the Working Environment, and the Norwegian National Institute of Occupational Health, 2019) Mbakaya, Charles
Collaborative occupational health and safety studies between counterparts in developing and developed countries and between developing countries have demonstrated their potential for improving occupational health and safety. Such collaboration in occupational health and safety is encouraged in the development of infrastructure in research empowerment and capacity building. This action includes the setting of priorities, the identification and documen- tation of problems, sponsorship, databases and surveillance systems, technical support, methodology, publishing, research and training programs, controlled intervention, information exchange, and networking. Examples of priorities in occupational health and safety in the developing world include the informal sector (informally hired and independent workers), temporary work, pesticides, accidents, dusts, carcinogens, solvents, ergonomics, wom- en and child labor, human immunodeficiency virus/acquired immunodeficiencey syndrome (HIV/AIDS), and transfer of hazardous materials and technologies. The sustainability of occupational health and safety structures and functions in the developing countries is a primary concern. Socioethical principles emphasize local, national, mutual and global gains. Examples of collaboration are given. Pervasive problems and strategies toward theirsolution are highlighted.
A combined microbial desalination cell and electrodialysis system for copper-containing wastewater treatment and high-salinity-water desalination
(Journal of Hazardous Materials, 2017) Donga, Yue; Liua, Junfeng; Sui, Mingrui; Ambuchi, John Justo; Qub, Youpeng; Wanga, Haiman; Fenga, Yujie
A new concept for heavy metal removal by forming hydroxide precipitation using alkalinity produced by microbial desalination cell (MDC) was proposed. Four five-chamber MDCs were hydraulically connected to concurrently produce alkalinity to treat synthetic copper-containing wastewater and salt removal. There was nearly complete removal of copper, with a maximum removal rate of 5.07 kg/(m3 d) under the initial copper concentration of 5000 mg/L (final pH of 7). The final copper concentration met the emission standard for electroplating of China (0.5 mg/L, GB 21900-2008). XRD analysis indicated copper was precipitated as Cu2Cl(OH)3. The best performance of MDCs in terms of average power density, salt removal and COD removal rate achieved in stage 3 were 737.3 ± 201.1 mW/m2, 53.6 ± 0.8 kg/(m3 d), and 1.84 ± 0.05 kgCOD/(m3 d) respectively. For purposes of water recovery, an electrodialysis (ED) system was presented based on in-situ utilization of generated electricity by MDCs as post-desalination treatmentfor salt effluent after sedimentation. The maximum discharging voltage of 12.75 ± 1.26V at switching time (Ts) of 15 min using a capacitor-based circuit produced a maximum desalination efficiency of 30.4 ± 2.6%. These results indicatedthatthis combinedsystemholds greatpromise for real-worldtreatment of copper- containing wastewater and deep desalination of high-salinity-water.
Combining ability of some sorghum lines for dry lands and sub-humid environments of East Africa
(2015-08-19) Rathore Abhishek; Beatrice Ang’iyo Were; Mary Mgonja; Deshpande Santosh; Mneney Emmarold; Onkware, Augustino; Gudu, Samuel; Ringo Justin
Sorghum (Sorghum bicolor L. Moench) is a major food crop grown in dry lands and sub-humid areas of East Africa. A study was conducted between 2010 to 2012 in dry lands (Miwaleni, Kiboko) and sub- humid (Ukiriguru) environments to identify parents for hybrid production. It involved 121 lines from ICRISAT and 121 hybrids developed from 36 male sterile lines and 42 restorer lines in a line × tester crossing. Experiments were planted in an alpha lattice design with three replications. Analysis revealed significant (P < 0.05) differences between parents and between crosses for yield and yield components, indicative of potentiality for exploitation. Line IESV23010 expressed best (-6.5) general combing ability (GCA) for days to 50% flowering (DAF). Highest general combiner for height was -55.4 expressed in ICSR24007 and for yield was 382.8 expressed in IESV92156DL. The crosses SDSA4×ICSR43 and SDSA4×ICSR59059 exhibited high and significant specific combining ability (SCA) for DAF. Lines IESB2 and ICSB44 were suited to sub-humid, whereas BTX623, ICSB15 and ICSB6 to dry lands environments. Testers IESV91104DL, IESV91131DL, ICSR93034 were well suited to dry lands whereas KARI-MTAMA1 and IESV23019 to sub-humid environments. The parents identified could be used to produce hybrids and varieties for the dry lands and sub-humid environments.

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