Publications by authors named "Shem O Wandiga"

In this work, the adsorption-desorption dynamics of diuron in three typical Kenyan agricultural soils, Nzoia (NZ), Thika (TH) and Machakos (MK) was investigated. The equilibrium adsorption data, tested against three classical nonlinear adsorption isotherms, was best described by the Freundlich model. The Freundlich adsorption constant, (K), increased in the order MK > TH > NZ soil.

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Polychlorinated biphenyls (PCBs) are chemicals that have become ubiquitous environmental pollutants due to their past use, persistence, and long-range transport thus requiring continuous monitoring. Therefore, this research was carried out to investigate spatial and temporal trends of seven indicator PCBs and two others (PCB 105 and PCB 156) in the Nairobi River. Levels of PCBs ranged from below detection limit (bdl) to 157.

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Modern anti-cancer drugs target DNA specifically for rapid division of malignant cells. One downside of this approach is that they also target other rapidly dividing healthy cells, such as those involved in hair growth leading to serious toxic side effects and hair loss. Therefore, it would be better to develop novel agents that address cellular signaling mechanisms unique to cancerous cells, and new research is now focussing on such approaches.

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Article Synopsis
  • New palladium (Pd)II and platinum (Pt)II complexes derived from Schiff base ligands were developed and characterized using various techniques such as FTIR and NMR.
  • Conductivity tests indicated that these complexes are neutral and potentially lipophilic, with molar conductivity ranges between 4.0-8.8 μS/cm.
  • The complexes displayed notable anticancer effects, reducing cell viability in multiple cancer cell lines by over 60-80%, while showing selectivity and low toxicity towards noncancerous cells, suggesting promise for further research.
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Throughout the world, waste sector has been implicated in significant contribution to anthropogenic greenhouse gas (GHG) emissions. Involving communities in recycling their solid waste would ensure climate change effect mitigation and resilience. This study was carried out to improve waste management practices through a community-led intervention at Kube-Atenda community in Ibadan, Nigeria.

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Production and use of most organochlorine pesticides (OCPs) was banned through the Stockholm Convention on persistent organic pollutants. However, appreciable amounts are still detected in the environment due to their persistence, illegal use, and releases from contaminated soils and obsolete stocks. The present study investigated the levels of OCP residues in Nairobi River.

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A series of complexes with oxathiacrown ethers appended to a [Ru(bpy)] moiety have been synthesized and characterised using H NMR, C NMR, IR, electronic absorption and emission spectroscopies, mass spectrometry and elemental analyses. The complexes exhibit strong MLCT luminescence bands in the range 608-611 nm and one reversible metal centred oxidation potential in the range 1.00-1.

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The concentrations of polycyclic aromatic hydrocarbons (PAHs) in Lates niloticus, Oreochromis niloticus and Rastrineobola argentea from three beaches were assessed to establish whether they are sources of human exposure in Kisumu Bay, Winam Gulf, Lake Victoria, Kenya. O. niloticus had 12 PAHs detected (TPAH 3.

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Trace metals Cadmium (Cd), Lead (Pb), Copper (Cu), Zinc (Zn) and Iron (Fe) were analyzed in edible portions of three main finfish species namely Lates niloticus, Oreochromis niloticus and Rastrineobola argentea sampled from various beaches of Winam Gulf, Lake Victoria, Kenya, in order to determine any seasonal and site variations and the results showed significantly (p < 0.05) higher mean concentrations of Cd, Cu, Zn and Fe during the wet season compared to the dry season for all the three species indicating the impact of wash-off into the lake during the rainy periods. The overall mean concentrations of the heavy metals (in μg/g dry weight) in all combined samples ranged from 0.

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This paper presents results based on determination of residue levels of 1,1,1-trichloro-2,2-bis[p-chlorophenyl]ethane (DDT) and its metabolites in five fish species from Rwenshama landing site on Lake Edward, Uganda. The residue levels were analysed by using a GC-ECD and confirmed by GC-MS. The DDT residues detected in fish samples from Lake Edward were p,p'-DDT, o,p'-DDT, p,p'-DDE, o,p'-DDE, p,p'-DDD and o,p'-DDD.

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Cholera epidemics have a recorded history in the eastern Africa region dating to 1836. Cholera is now endemic in the Lake Victoria basin, a region with one of the poorest and fastest growing populations in the world. Analyses of precipitation, temperatures, and hydrological characteristics of selected stations in the Lake Victoria basin show that cholera epidemics are closely associated with El Niño years.

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