58 research outputs found
Occurrence of a Polychlorinated Biphenyl (PCB) Congener in Surface Water, Sediments and Blackchin Tilapia (Sarotherodon melanotheron) from Ologe Lagoon, Nigeria
Polychlorinated biphenyls (PCBs) are persistent organochlorine chemicals that are toxic to aquatic organisms and humans. PCBs levels were assessed in surface water, sediments and fish from Ologe Lagoon, a major water body receiving treated effluents from Agbara Industrial Estate, using Gas Chromatograph-Electron Capture Detector (GCECD). 2,4,4’-Trichlorobiphenyl (2,4,4’-TCB) was the only PCB congener detected in the assessed matrices. Sediment 2,4,4’-TCB levels ranged from 0.0033±0.00333 to 0.0430 ± 0.00351ng/g. There was a significant (p < 0.05) seasonal variation in the levels in sediments and surface water. The level in surface water from Zone 3 was above USEPA’s safe limit (0.0005 mg/L) in the rainy season. There was no significant (p > 0.05) seasonal difference in the mean concentrations of 2,4,4’-TCB in fish, and the levels were lower than WHO’s safe limit (0.2 mg/kg). Based on the negligible to low levels of 2,4,4’-TCB in S. melanotheron inhabiting the lagoon, the fish was considered safe for consumption. Levels of 2,4,4’- TCB found in the sediments and surface water in this study indicate that levels may change with season, therefore, we recommend that the concentrations of the compound are regularly monitored in order to timely avert toxic levels of bioavailable 2,4,4’-TCB in the water body.Keywords: Polychlorinated biphenyls, Sarotherodon melanotheron, Sediments, Surface water
Assessment of the environmental impacts of solous municipal solid waste landfills using soil properties and earthworms (Eudrilus eugeniae)
This study assessed the effects of Solous Municipal Solid Waste Landfills on soil properties, heavy metal contamination and macro-invertebrates (earthworms). Soil and earthworm samples were collected from Solous municipal solid waste landfills with reference samples obtained from the Botanical Garden, University of Lagos and taken to the laboratory for analyses using standard methods. Results showed that pH and organic matter values of soil samples from the landfills ranged from 8.51±0.88 to 9.85±0.02 and 5.79±0.53 % to 7.11±1.19 % respectively, and they were statistically (P < .05) higher than the values of the reference samples. Most of the assessed heavy metals in soil and earthworms from the landfills were significantly (P < .05) higher when compared to the reference samples. The antioxidant enzymes and lipoperoxidation product levels were significantly (P < .05) higher in earthworms from most of the landfills in relation to the reference samples. The mean total protein concentrations in annelids from the landfills were lower than the mean concentration in the reference samples, however, only those from two of the landfills (Solous B and C) were significant (P < .05). Histological studies showed that the clitella of earthworms from the landfills had abnormalities such as disruption of body wall muscle layers, cellular degeneration, oedematous longitudinal muscle, and dark brown pigments. Solous Landfills had an obvious effect on the assessed abiotic and biotic parameters, and could be a source of heavy metal pollution in nearby vicinities especially their groundwater sources and surface water.Keywords: Biochemical markers, Bioindicator, Eudrilus eugeniae, Heavy metals, Landfill, Soil propertie
The Road to Academic Excellence : The Making of World-Class Research Universities
For middle-income and developing countries as well as some industrial nations a major challenge for building and sustaining successful research universities is determining the mechanisms that allow those universities to participate effectively in the global knowledge network on an equal basis with the top academic institutions in the world. These research universities provide advanced education for the academic profession, policy makers, and public and private sector professionals involved in the complex, globalized economies of the 21st century. In addition to their contribution to economic development, these universities play a key societal role by serving as cultural institutions, centers for social commentary and criticism, and intellectual hubs. The positive contribution of tertiary education is increasingly recognized as not limited to middle-income and advanced countries, because it applies equally to low-income economies. Tertiary education can help these countries to become more globally competitive by developing a skilled, productive, and flexible labor force and by creating, applying, and spreading new ideas and technologies. A recent study on how to accelerate economic growth in Sub-Saharan Africa spells out the crucial contribution of tertiary education in supporting this endeavor (World Bank 2008). It observes that the key for success in a globalized world increasingly lies in how effectively a country can assimilate available knowledge and build comparative advantages in areas with higher growth prospects and how it can use technology to address the most pressing environmental challenges. The main chapters of this book are nine case studies that illustrate what it takes to establish and sustain research universities and help validate the analytical model outlined above, including the paths to building research excellence
Literacy and multilingualism in Africa
Literacy and multilingualism in Africa is approached here as a field of practice rather than a unified field of research. This field presents a crucial paradox: African contexts present some of the world’s most diverse and vital multilingual situations but also feature in the world’s poorest literacy rates and are routinely said to lack a literate tradition altogether. By reviewing Africa’s script inventions this chapter offers counter-evidence for this deceptive view. Throughout Africa – from the Maghreb over West and Central Africa to the Horn of Africa – there have been significant indigenous script traditions and inventions, including Tifinagh, N’ko, Vai, Bamum and Ge’ez. In fact, some of the world’s oldest known scripts (e.g. Egyptian hieroglyphs) are African scripts. The chapter further outlines two relatively young fields of practice and research that have begun to make major contributions to literacy and multilingualism in Africa: digital literacy and linguistic landscape. These fields share a common interest in the materiality of real language as opposed to idealized images of language and in local agency and creativity in the site of struggle that is language. Like digital language practices, linguistic landscapes constitute a domain for African written multilingualism that is not generally supported or monitored by African states. Nor does either field present simple continuities from colonially inherited language policies and ideologies, in the way that classrooms do. As spaces for writing par excellence linguistic landscapes and mobile phones promise to contribute in no minor way to the development of African language literacies and multilingualism in Africa
Ascertaining the value of a virtual team strategy in development projects: a synchronicity conceptualization of communication performance
This research addresses the question of whether or not the adoption of a virtual team strategy creates value throughout the duration of a development project. It looks at the context in which communication occurs, and then examines the practices that are effective in facilitating communication performance. The thesis also presents discussions on the emerging new perspective of media synchronicity and its applicability to the analysis of the Nigerian operations of a development programme.Data collection is centred on Enterprise Resource Planning (ERP) activities. With that in consideration, the research adopts a case study design. The technique of template analysis is applied in the analysis of qualitative data. Three work systems involved in the ERP setting (i.e.Applications Development, Business Services and Infrastructure Support) are examined.Empirical analysis shows that communication media characteristics tend to influence an individual’s behaviour. People also behave differently based on the set of tool, policies and practices open to them – and so virtual teams don't all function in the same way. Research outcomes also contribute to managerial practices: it is suggested that enforcing appropriate control mechanisms can be more beneficial in a virtual team than instilling trust. Socio-emotional functions hold important implications for performance within these environments
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