Strategic Approach for Controlling Soil and Groundwater Contamination in Urban and Rural Areas of Nigeria

Soil pollution and groundwater contamination are rampant in urban and rural areas of various developing countries including Nigeria. The quality of groundwater is a vivacious concern for human beings since it is directly associated with the human welfare and it is needed to conserve water resources. This paper x-rays strategic approach for controlling soil and groundwater contamination to enhance the efficiency of civil and environmental engineering design through recent trends and practice which will play a vital role in handling environmental pollution. Strategic approach highlighted involves the formulation and implementation of the major goals and initiatives based on consideration of resources and an assessment of the internal and external environments in which the organization competes. One or more of these approaches are often combined for more cost-effective treatment. The field studies for assessment of contamination comprised of detailed hydro-geological investigations which include geophysical investigations, borehole drilling, development of monitoring wells, followed by collection and analysis of existing field samples (dumpsite, subsurface soil and groundwater) are very critical for efficient handling of environmental pollution. It has been concluded that basic necessities for a healthy environment and public health include clean air, safe and sufficient water Safe and adequate food, safe and peaceful settlements, stable global environment in order to achieve excellent public health without soil pollution and groundwater contamination. Strategic approaches to remediation of contaminated soils include isolation, bioremediation, immobilization, toxicity reduction, physical separation and extraction

Optimization of the Operational Conditions for Cross Flow Turbine Developed for Power Generation

In a bid to optimize the performance of a Cross Flow Turbine designed and fabricated by Oyebode (2014), the performance evaluation of the turbine at various conditions was carried out using a portion of the overflow from the University of Ilorin (UNILORIN) dam. The Dam has a net head of 4 m, flow rate of 0.017m3 and hence theoretical hydropower energy of 668W. The turbine was tested and the optimized value of operating conditions namely; angle of inclination of the water jet (15o above tangent, tangential and 15o below tangent), height of water jet to impact point (200mm, 250mm and 300mm) and length of the water jet to impact point (50mm, 100mm and 150mm) were pre-set at their various levels while testing the Turbine. The measured outputs were Turbine Speed, Turbine Torque, Alternator Speed as well as the output voltage. The optimum values of the process output or measured parameters were determined statistically using a 33X2 factorial experiment in three replicates. An optimum turbine speed of 330.09 rpm was achieved by pre-setting 250mm height to impact point, 100mm length to impact point and the water jet 15º below tangent. Same combination also yielded an optimum turbine torque of 39.07kNm. During loading (i.e. when the alternator becomes connected to the turbine), an optimum Turbine Speed of 197.66rpm was achieved by pre-setting 250mm height to impact point, 100mm length to impact point and the water jet 15º below tangent. Same combination also yielded an optimum Turbine Torque of 25.02kNm, optimum Alternator speed of 879.24rpm and an optimum output voltage of 4.05V. The results therefore show that the turbine must be set at these operational conditions for it to perform optimally. Key words: Micro hydropower, Cross Flow turbine, Power generation, Dam overflo

Development of Hydropower Turbines Powered by Dam Overflow

The epileptic power supply in most rural areas in Nigeria and its attendant negative impact on the economy of the Nation, Agricultural productivity and huge rural emigration, is a serious source of concern. This necessitated the development of two hydro-power turbines powered by the overflow (which was rather considered a waste) from University of Ilorin (UNILORIN) dam. A portion of the overflow was channeled into a Polyvinyl Chloride (PVC) pipe and the flow rate was calculated to be 0.017m3/sec using the bucket method. The change in elevation between the overflow and the point of usage was reported to be 4m. The flow (Q) and Head (h) were typical values for many streams and rivers in different rural areas of Nigeria, hence its suitability and adoption for this study. Two turbines viz: Pelton Wheel (PW) and Cross Flow (CF) were developed and tested. The PW generated a speed of 538.4rpm and a torque of 46.2kNm at off load condition while the CF generated a speed of 330.1rpm and a torque of 39.07kNm at the same condition. During loading – when the alternator had been connected to the turbine - the PW turbine speed and torque became 392.0rpm and 36.5kNm respectively, while that of the CF became 197.7rpm and 25.0kNm respectively. A belt and pulley mechanism was used to deliver the rotational speed to the alternator and this increased the alternator speed from the PW and CF turbines to 1768.6rpm and 879.24rpm respectively. The speed from the PW was enough to power the alternator as the alternator only requires 1500rpm to function optimally. The PW was thus adjudged the most suitable for use

Differential protection of neuromuscular sensory and motor axons and their endings in Wld(S) mutant mice

Orthograde Wallerian degeneration normally brings about fragmentation of peripheral nerve axons and their sensory or motor endings within 24-48 h in mice. However, neuronal expression of the chimaeric, Wld(S) gene mutation extends survival of functioning axons and their distal endings for up to 3 weeks after nerve section. Here we studied the pattern and rate of degeneration of sensory axons and their annulospiral endings in deep lumbrical muscles of Wld(S) mice, and compared these with motor axons and their terminals, using neurone-specific transgenic expression of the fluorescent proteins yellow fluorescent protein (YFP) or cyan fluorescent protein (CFP) as morphological reporters. Surprisingly, sensory endings were preserved for up to 20 days, at least twice as long as the most resilient motor nerve terminals. Protection of sensory endings and axons was also much less sensitive to Wld(S) gene-copy number or age than motor axons and their endings. Protection of γ-motor axons and their terminals innervating the juxtaequatorial and polar regions of the spindles was less than sensory axons but greater than α-motor axons. The differences between sensory and motor axon protection persisted in electrically silent, organotypic nerve-explant cultures suggesting that residual axonal activity does not contribute to the sensory-motor axon differences in vivo. Quantitative, Wld(S)-specific immunostaining of dorsal root ganglion (DRG) neurones and motor neurones in homozygous Wld(S) mice suggested that the nuclei of large DRG neurones contain about 2.4 times as much Wld(S) protein as motor neurones. By contrast, nuclear fluorescence of DRG neurones in homozygotes was only 1.5 times brighter than in heterozygotes stained under identical conditions. Thus, differences in axonal or synaptic protection within the same Wld(S) mouse may most simply be explained by differences in expression level of Wld(S) protein between neurones. Mimicry of Wld(S)-induced protection may also have applications in treatment of neurotoxicity or peripheral neuropathies in which the integrity of sensory endings may be especially implicated

Modelling Water Productivity of Selected Grain Crops in Rain-fed and Surface Irrigated Fields in Northern Nigeria

Field trials of selected grain crops (rice, wheat and maize) were conducted for three years under rain-fed and surface irrigated systems to evaluate their water productivity and model same. A completely randomized design (CRD) experiment was used at the Irrigation Research Station, Kadawa, Kano State. Rice yield was 11.6, 9.9 and 5.3 tons/ha; wheat yield was 1.46, 1.92 and 2.0 tons/ha, while Maize yield was 0.8, 0.4 and 0.91 tons/ha in the 2009/2010, 2010/2011 and 2011/2012 cropping season, respectively. ANOVA revealed a highly significant difference in the yield of paddy rice, wheat and maize at both 1 % and 5% significant levels (Fcalc>Ftab), with p-value of 0.0002, 0.004 and 0.001 for rice, wheat and maize respectively. Crop – water productivity models developed revealed that optimum crop yield of 12.8 tons/ha of paddy rice, 2.7 tons/ha of wheat and 0.94 tons/ha of maize is achievable with 58.3 cm of rainfall, 34 cm and of 29.8 cm of irrigation water respectively

Evaluation of chloride mass balance and recharge in agricultural lands in Nigeria

Groundwater salinization studies and recharge estimation was carried out at the Irrigation Research Station, Kadawa, Nigeria. Groundwater samples from fifteen randomly selected piezometer locations were analyzed monthly for chloride using Mohr’s method for three years while recharge was estimated using the chloride mass balance (CMB) method. Groundwater chloride range from 22 - 91.4 mg/l, seasonal trend was identified with the hot dry season (April – June) having higher values than the wet season (July – October). Correlation analysis revealed chloride status that is not associated with one another in all soil types while salt build up was observed at the south western tip of the farmland indicating potential reduction of agricultural productivity. CMB revealed a mean annual recharge of 869 mm; the method was found to underestimate recharge because it does not account for lateral flow contribution, hence should be discouraged as a stand-alone methodology for recharge studies. Salt build-up was exacerbated by the collapse of the drainage system. Reconstruction of the drainage systems using tile drains should be executed to control the rising water level in the area; conjunctive use of groundwater and surface water is recommended to maximally utilise available water in order to ensure ecological sustainability and free some water for other uses

Medical Waste Management and Design of a Low-Cost Incinerator for Reduction of Environmental Pollution in a Multi-System Hospital

Pollution of the environment and inappropriate management of medical wastes are major challenges facing developing countries and this must be tackled with recent technology for public health, enhanced natural ecosystems, and a better environment. This research is a two-step process that involves the assessment of the existing Hospital waste management practices in a multi-system Hospital in Ado-Ekiti, Nigeria. Excess air, kerosene (auxiliary fuel), single chamber, Batch-fed (Manual feeding), and controlled air incinerator were designed. Wastes were loaded once at the beginning of the combustion cycle followed by combustion, ash burnout, cool down, and ash removal to assist medical waste management. Findings revealed that personnel involved in handling medical waste were equipped with inadequate protective gear. Medical waste was handled together with municipal waste and both wastes were incinerated in an open dumpsite without engineered sanitary landfill at disposal locations constituting a nuisance with a high risk of pollution to the surrounding environment. The incinerator was designed for a waste load of 269 kg.day-1. It consists of four zones; the waste and combustion zone (2.7 m × 1.8 m × 1 m), the ash zone (0.23 m height), the combustion fumes and one-second retention zone (0.43 m height) as well as the excess air zone (0.46 m height). This low-cost medical waste incinerator has a lot of improvement, operational effectiveness, and efficiency to the currently available techniques. Viable recommendations made will improve the state of environmental health and reduce the harmful effects of medical waste

Intersections between the culture of Xiao (孝) and caring for older relatives in China: perspectives of United Kingdom-based Chinese students on future care for their parents

Emphasis placed on Xiao (孝; filial piety) in Chinese culture highlights parents' investment in their children with the expectation of being cared for when older. An increasing number of Chinese students come to the United Kingdom (UK) to study, with the majority returning home and likely to become future care-givers for their parents. Little attention has been paid to the implications of transnational mobility of Chinese students on the reciprocal aspects of future care responsibility. With the uniquely changing family structure due to consequences of the One-Child Policy, we conducted proactive research on the opportunities and challenges that Chinese transnational students anticipate they may face in future care-giving for elderly parents. Hence, this study's aim was to make a novel contribution to knowledge through exploration of the perspectives of Chinese students in England on intergenerational ties and filial obligations. Adopting a social constructivist philosophical position, we conducted three focus groups with 19 UK-based Chinese students, using a semi-structured topic guide with informed consent. Interviews were translated, transcribed and analysed using reflective thematic analysis, capturing semantic and latent meanings, and employed a descriptive and interpretative approach. Six themes were discovered, revealing a ‘culture of duty’ where familial obligation and societal expectations were prominent. Prospective care-givers anticipated a future dilemma between balancing work commitments and providing care as mandated by Xiao. Furthermore, it appeared that lack of preparedness might further exacerbate barriers faced when accessing support. We surmised that the changing demographics and absence of formal support could compound stressors over time, especially if cognitive dissonance arises as realities of life do not fit with societal expectations. Our findings imply that policy makers, practitioners and the government will need to adequately support prospective family care-givers who are returnees in caring for older generations

Exploration of meaning, motivation, and preparedness to care amongst the One‐Child Policy generation in China

Objectives: In China there is a cultural expectation (Xiao, 孝- filial piety) that offspring should provide care for their parents. However, the sustainability of this is threatened by the impact of the One-Child Policy (1979-2015), which has resulted in a diminution in numbers of children available to care, rapid urbanisation and increase in the number of women in employment. In this context, the objective was to explore the motivations, meaning, and preparedness for future caregiving of offspring affected by the OCP. Design and Methods: We adopted a constructivist position using a hermeneutic phenomenology approach and interviewed eight current and prospective caregivers aged 20-35 years about future caregiving responsibilities. Data were obtained through in-depth interviews, analysed using reflective Thematic Analysis. Results and conclusion(s): Three prominent themes: (i) Caregiving beliefs, (ii) Caregiving conditions and (iii) Contextual factors were identified under an overarching theme “Competing pressures- meanings, motivation and preparedness”. Despite the inherent stress, participants envisaged providing or organising care in the future to fulfil Xiao, and most viewed long-term care settings as unviable. Ultimately, the findings suggested that the actual performance of caregiving would not always measure up to ideal expectations, resulting in ‘filial discrepancy’ i.e., a gap between societal expectations for caregiving to older relatives and actual caregiving performance. This could adversely impact the caregivers and quality of care provided. The findings highlighted the urgent need to develop culturally attuned services, including education and training for family caregivers, health and social care professionals

Performance evaluation of selected infiltration equations for irrigated (FADAMA) soils in Southern Kaduna Plain, Nigeria

ABSTRACT The need for continuous and in-depth study on the applicability and accuracy of infiltration equations cannot be exhausted since equation parameters and performance vary for different soils. The study reported herein, has evaluated four infiltration equations (Kostiakov's; Philip's; Horton; Talsma and Parlange). The field water infiltration data used in these equations were based on double ring infiltrometer tests conducted for 4 hours at two fadama irrigation area (Kuda and Kukumdaji). Measurements were made at two sites in each of the two Fadama irrigation area based on land management practice (Cultivated/fallow) giving a total of four experimental sites. The results of the measured infiltration rates reveals that site 2 (Kuda/fallow) gave the highest average final infiltration rate of 69mm/hr followed by site 1(Kuda/cultivated) of value 52mm/hr and then site 3(Kukumdaji/cultivated) of value 35mm/hr while site 4 (Kukumdaji/fallow) recorded the least of 18mm/hr. Results of the Comparism between measured and predicted infiltration rates reveal that Kostiakov's and Philip's equation gives the best fit when compared with the rest of the equations tested. Results from the study conclude that Kostiakov's and Philip's equation can be used to predict infiltration rates for the soil studied but that Kostiakov's equation approximated the measured infiltration rates with higher accuracy and best fit than did Philip's and Horton's equation. Talsma and Parlange's equation fail to approximate measured data particularly in the early stage of measurement