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    Indigenous strategies and empirical models for adaptability of the maize-bean intercropping system to climate change
    (UZ Foundatoin, 2016-12) Mapanda, S.; Chitja, J. M.; Duffy, Kevin Jan
    This review article discusses on different ways of indigenous strategies and empirical models as an adaptation to climate change by smallholder farmers in Africa. Indigenous adaptation strategies are methods that enable individuals or communities to adjust to the impacts of climate change in local areas. Some of the strategies practiced are: zero tillage, mulching, soil management techniques, organic agriculture and fallow system of cultiva-tion, intercropping with legumes, early planting and use of tolerant varieties to drought, water conservation and crop diversification. Scientists developed many empirical models that are used to project the impact of climate change to agriculture. Some of the empirical models include: CERES-Maize Crop Model, Global Circulation Models (GCM) and histori-cal data records. There is also use of empirical evidence such as indigenous land unit framework, indigenous early warning systems, use of rainmakers, movement of birds, ants and crying of dogs by the indigenous smallholder farmers in Africa. Intercropping system is the best practice used as a strategy to climate change adaptability, and one of the most suitable intercropping systems is that of maize and bean. However, the current research findings revealed that there is a lack of consideration of indigenous knowledge that could enhance livelihoods that depend on natural resources directly affected by climate change.
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    Characterization of brewery wastewater composition
    (WASET, 2015) Enitan, Abimbola Motunrayo; Adeyemo, Josiah; Kumari, Sheena K.; Swalaha, Feroz Mahomed; Bux, Faizal
    Industries produce millions of cubic meters of effluent every year and the wastewater produced may be released into the surrounding water bodies, treated on-site or at municipal treatment plants. The determination of organic matter in the wastewater generated is very important to avoid any negative effect on the aquatic ecosystem. The scope of the present work is to assess the physicochemical composition of the wastewater produced from one of the brewery industry in South Africa. This is to estimate the environmental impact of its discharge into the receiving water bodies or the municipal treatment plant. The parameters monitored for the quantitative analysis of brewery wastewater include biological oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids, volatile suspended solids, ammonia, total oxidized nitrogen, nitrate, nitrite, phosphorus and alkalinity content. In average, the COD concentration of the brewery effluent was 5340.97 mg/l with average pH values of 4.0 to 6.7. The BOD5 and the solids content of the wastewater from the brewery industry were high. This means that the effluent is very rich in organic content and its discharge into the water bodies or the municipal treatment plant could cause environmental pollution or damage the treatment plant. In addition, there were variations in the wastewater composition throughout the monitoring period. This might be as a result of different activities that take place during the production process, as well as the effects of peak period of beer production on the water usage.
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    Symmetrized exponential oscillator
    (World Scientific Publishing, 2016-09-01) Znojil, Miloslav
    Several properties of bound states in potential V(x) = g² exp(Formula presented.)x(Formula presented.) are studied. Firstly, with the emphasis on the reliability of our arbitrary-precision construction, wave functions are considered in the two alternative (viz. asymptotically decreasing or regular) exact Bessel-function forms which obey the asymptotic or matching conditions, respectively. The merits of the resulting complementary transcendental secular equation approaches are compared and their applicability is discussed.
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    Synthesis and performance evaluation of a new polymeric composite for the treatment of textile wastewater
    (ACS Publications, 2015) Gupta, Sanjay Kumar; Nayunigari, Mithil Kumar; Misra, Rohit; Ansari, Faiz Ahmad; Dionysiou, Dionysios (Dion) D.; Maity, Arjun; Bux, Faizal
    Azo dyes are synthetic colorants widely used in textile industry and are considered to be major contaminants in dye wastewater. Coagulation−flocculation is most preferred techniques to treat dye wastewater. A N,N-diisopropylamine-based new polymer was synthesized by polycondensation of epichlorohydrin, N,N-diisopropylamine, and ethylinediamine. The chemical and thermal properties of the polymer were investigated by FTIR, XRD, TGA, and viscosity measurements. The flocculation efficiency of the polymer was evaluated at different coagulant dose, organic load, and pH. The flocculation efficiency of this polymer was found to be higher over a pH range of 2−10 at its optimal dose of 80 mg/L. Morphological changes in the floc were studied by light and scanning electron microscopy. The zeta potential results clearly indicated that flocculation at the optimum doses is the result of charge neutralization and adsorption bridging. This study demonstrates the successful synthesis of the polymer, its excellent color removal efficiency (>98%) at lower doses, and effectiveness in dye wastewater treatment.
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    Uptake of inorganic and organic nutrient species during cultivation of a Chlorella Isolate in Anaerobically digested dairy waste
    (American Institute of Chemical Engineers, 2016-06-23) Wahal, Shantanu; Viamajala, Sridhar
    A natural assemblage of microalgae from a facultative lagoon system treating municipal wastewater was enriched for growth in the effluents of an anaerobic digester processing dairy waste. A green microalga with close resemblance to Chlorella sp. was found to be dominant after multiple cycles of sub-culturing. Subsequently, the strain (designated as LLAI) was isolated and cultivated in 203 diluted digester effluents under various incident light intensities (255–1,100 mmoles m22 s21) to systematically assess growth and nutrient utilization. Our results showed that LLAI production increased with increasing incident light and a maximum productivity of 0.34 g L21 d21 was attained when the incident irradiance was 1,100 mmoles m22 s21. Lack of growth in the absence of light indicated that the cul-tures did not grow heterotrophically on the organic compounds present in the medium. How-ever, the cultures were able to uptake organic N and P under phototrophic conditions and our calculations suggest that the carbon associated with these organic nutrients contributed significantly to the production of biomass. Overall, under high light conditions, LLAI cul-tures utilized half of the soluble organic nitrogen and >90% of the ammonium, orthophos-phate, and dissolved organic phosphorus present in the diluted waste. Strain LLAI was also found to accumulate triacylglycerides (TAG) even before the onset of nutrient limitation and a lipid productivity of 37 mg-TAG L21 d21 was measured in cultures incubated at an inci-dent irradiance of 1,100 mmoles m22 s21. The results of this study suggest that microalgae isolates from natural environments are well-suited for nutrient remediation and biomass pro-duction from wastewater containing diverse inorganic and organic nutrient species
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    Polyhydroxyalkanoates production from fermented paperboard mill wastewater using acetate-enriched bacteria
    (Springer-Verlag Berlin Heidelberg, 2017) Farghaly, Ahmed Mustafa; Enitan, Abimbola Motunrayo; Kumari, Sheena K.; Bux, Faizal; Tawfik, Ahmed
    The aim of the study was to investigate the use of dark fermented paperboard mill wastewater (PMW) containing volatile fatty acids for polyhydroxyalkanoates (PHA) production. Six sequencing batch reactors (SBRs) were initially fed with synthetic feed containing acetate and operated at different organic loading rates (OLRs) of 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 gCOD l-1 day-1 for PHA-storing bacteria enrichment. The maximum PHA content and yield (YPHA/S) were 67.44 ± 5.88 % and 0.45 ± 0.39 C-mol C-mol-1 at OLR of 1.5 gCOD l-1 day-1, respectively. The synthetic feed was replaced by dark fermented PMW effluent rich in acetate, butyrate, propionate, and lactate at the accumulation stage resulting in a PHA content and yield of 58.57 ± 4.02 % and 0.46 ± 0.09 C-mol C-mol-1, respectively. The maximum specific PHA production rate max ) amounted to 0.29 ± 0.1 C-mol C-mol-1 X-1 h-1.(qPHA Illumina MiSeq sequencing of bacterial 16S rRNA gene showed that Proteobacteria and Bacteroidetes increased from 37.4 to 77.6 % and from 2.49 to 17.66 % at enrich-ment and accumulation stages, respectively. Actinobacteria (15.44 %), Chloroflexi (8.15 %), Planctomycetes (7.46 %), and Acidobacteria (6.0 %) were detected at the enrichment SBRs.
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    Dual role of Chlorella sorokiniana and Scenedesmus obliquus for comprehensive wastewater treatment and biomass production for bio-fuels
    (Elsevier, 2016) Gupta, Sanjay Kumar; Ansari, Faiz Ahmad; Shriwastav, Amritanshu; Sahoo, Narendra Kumar; Rawat, Ismail; Bux, Faizal
    Microalgal treatment of raw sewage presents many complexities, mainly resulting from the inability of the algal species to sustain increased physiological stresses due to variable nutrient levels and high concentrations of organics. Chlorella sorokiniana and Scenedesmus obliquus have been identified to tolerate higher amounts of organic loading and physiological stresses. Nutrient removal, pathogen removal, and lipid accumulation with secondary or tertiary effluents have been demonstrated inde-pendently for these organisms. However, their potentials for accomplishing these objectives simulta-neously with raw sewage have not been investigated. This study presents comprehensive investigations of applicability of C. sorokiniana and S. obliquus to wastewater treatment without the requirement for any additional treatment. S. obliquus showed greater potential for removing organic carbon (76.13 ± 1.59%COD removal), nutrients (98.54 ± 3.30% N-removal, 97.99 ± 3.59% P-removal) and comparable pathogens removal (99.93 ± 0.12% total coliforms removal, 100% faecal coliform removal) in comparison to C. sorokiniana (69.38 ± 1.81% COD removal, 86.93 ± 3.49% N-removal, 68.24 ± 11.69% P-removal, 99.78 ± 0.12% total coliforms removal, 100% faecal coliform removal) with 15 days of cultivation with filtered raw sewage, but also encountered increased levels of stress (Fv/Fm of 0.48 ± 0.03) which accounted for increased lipid accumulation in the cells (23.26 ± 3.95% w/w) but might also affect their biomass productivity and treatment potential in longer applications. In comparison, C. sorokiniana demonstrated better adaptability to physiological stresses (Fv/Fm of 0.53 ± 0.01) and may be suitable for achieving comprehensive treatment and sufficient lipid accumulation (22.74 ± 3.11% w/w) without compromising these potentials during prolonged applications. These results highlight the importance of selecting algal species with better stress resistance to extend their applicability for comprehensive wastewater treatment and lipid production.
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    An innovative electrochemical process to alleviate the challenges for harvesting of small size microalgae by using non-sacrificial carbon electrodes
    (Elsevier, 2015-09-04) Guldhe, Abhishek; Misra, Rohit; Singh, Poonam; Rawat, Ismail; Bux, Faizal
    Harvesting of microalgal biomass is still a bottleneck to its commercial scale application, due to small cell size, low culture densities, colloidal stability and thus unfavourable economics. Centrifugation is an efficient technique but the high energy consumption makes it unsuitable for low value microalgal products. Chemical flocculation and filtration are inefficient and time consuming methods for harvesting of small size microalgae. In this study, an electrochemical harvesting (ECH) process was assessed for the harvesting of a small size microalga Ankistrodesmus falcatus by using non-sacrificial carbon electrodes. Harvesting efficiency of ECH was compared to centrifugation and flocculation using alum and chitosan. The highest recovery efficiency was obtained by cen-trifugation (93% after 15 min) followed by ECH process (91% after 30 min), alum (86% after 60 min) and chitosan (55% after 60 min). However, the energy consumption of ECH process (1.76 kWh kg−1) was much lower than the centrifugation process (65.34 kWh kg−1). The biochemical composition of harvested biomass was also assessed, and it was found that the ECH process has no deteriorating effect on the quality of biomass. High recovery effi-ciency, low energy consumption and the use of non-sacrificial electrodes make ECH a sustainable harvesting technique for small size microalgae.
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    Cultivation of Chlorella pyrenoidosa in outdoor open raceway pond using domestic wastewater as medium in arid desert region
    (Elsevier, 2016) Dahmani, Siham; Zerrouki, Djamal; Ramanna, Luveshan; Rawat, Ismail; Bux, Faizal
    Chlorella pyrenoidosa was cultivated in secondary wastewater effluent to assess its nutrient removal capa-bilities. Wastewaters were obtained from a wastewater treatment plant located in Ouargla, Algeria. The experiments were conducted in winter under natural sunlight in an outdoor open raceway pond situated in the desert area. The highest biomass of the microalgae was found to be 1.71 ± 0.04 g/L. Temperatures ranged between 18 and 31 C. The average annual insolation was no less than 3500 h with an annual solar irradiance of more than 2000 kWh/m2. Analyses of different parameters including COD, NH4-N and TP were conducted throughout the cultivation period. Their average removal efficiencies were 78%, 95%and 81% respectively. The results demonstrated the potential of nutrient removal by microalgae grown on secondary wastewater in arid areas.
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    Effect of interaction of methanol leaf extract of Spondias Mombin (Linn) and Amoxicillin on some Diarrheagenic Escherichia coli
    (Pharmacotherapy Group, 2016-03) Adegoke, Anthony Ayodeji; Aiyegoro, Olayinka A.; Stenström, Thor-Axel
    Purpose: To study the effect of interaction between methanol leaf extract of Spondias mombin and amoxicillin on diarrheagenic Escherichia coli (DEC). Methods: Cold methanol extraction of Spondias mombin leaf and its phytochemical screening were carried out. Isolated, characterized and identified strains of enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), and enterohemorrhagic E. coli (EHEC) from watery stool, mucoid bloody stool and watery bloody stool of diarrheal patients, respectively, were confirmed and typed by conventional and molecular methods. The minimum inhibitory concentration (MIC) and ½ MIC at which the extract and amoxicillin interacted were determined. Results: Spondias mombin extract showed remarkable antibacterial activity at extract concentration of 50 - 200 mg/mL with a mean zone of inhibition (MZ) ≥ 11.1 and activity index (AI) of 0.8 - 1.1. MIC of 12.5 mg/mL was observed for both ETEC and EIEC while it was 6.25 mg/mL for EHEC. The extract showed synergistic interaction at various concentrations (50 – 200, 12.5 and 6.25 mg/mL, respectively) with amoxycillin against ETEC, EHEC and EIEC. Synergy across a wide range of concentrations compared favourably with the ½ MIC and MIC of both extract and amoxycillin for ETEC. The extract contained moderate levels of alkaloids, flavonoids and tannins, as well as a lot of saponins, and low levels of phenol. The activity of the extract of Spondias mombin compares well with that of amoxicillin with AI ≥ 1 in some cases. Conclusion: A synergistic interaction between the leaf extract of S. mombin and amoxicillin confirms the extract as potential antibacterial agent but further studies are required to ascertain this.