MINE DEWATERING: A VERITABLE COMPONENT IN MINE COST ANALYSIS IN THE DEVELOPMENT AND MINING OF THE LAFIA-OBI COAL, NIGERIA

The impact of water in surface and underground mining activities is of great concern to Mining Engineers and Geoscientists to the effect that its accumulation in excess quantity can render mining of minerals ineffective. Surface and underground mines must therefore constantly be dewatered in order to forestall over-flooding and its attended effects on mining machinery, infrastructures industrial health, and productivity. In mine planning and design the cost of dewatering of mines is often captured as capital costs at the initial stage of mine development and afterwards in the cause of mining as operating costs both playing significant roles in profit or loss of Mining companies. Mines are often excavated below the water table where mine voids serve as low-pressure sinks inducing groundwater to move to the openings from the surrounding saturated rock. The result is the dewatering of nearby rock units via drainage of fractures and water-bearing strata in contact with the mine workings. There is also the potential for impacts to more remote water-bearing units and surface water bodies depending on the degree of hydrologic communication. The extent and severity of the impact on the local surface water and groundwater systems depends on the depth of the mine, the topographic and hydro-geologic setting, and the hydrologic characteristics of adjacent strata. The dewatering of mines and its cost implications starts from mineral exploration and mine development from where the rate of water flow is approximated thereby providing the initial clue to the choice of dewatering pumps and other drainage infrastructures. The paper dwells on the sources of water and its menace in surface and sub-surface mines, its control, and effects on the cost analysis of mineral investments

Engineering Students’ Virtual Learning Challenges during COVID-19 Pandemic Lockdown: A Case Study

As a result of the pandemic lockdown, most Faculty, Staff, and students in Nigerian universities were unable to learn online because of irregular power and internet unavailability. As a major concern to the Nigerian Deans of Engineering, a study was commissioned by the Deans to identify the extent of the problem with a view to identifying the research and development areas and proffer an indigenous solution to the problems identified. This paper discusses the results of an online survey administered during the lockdown to a stratified sample size from the over 80,000 engineering students’ population in Nigeria. The initial results showed that there is need to develop some form of a cost�effective but modular and mobile integrated boosted internet�ready power system suitable for teaching, learning and research which is always-on both day and night for learning

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

MITIGATING THE ACTIVITIES OF ARTISANAL AND SMALL-SCALE MINERS IN AFRICA: AN OVERVIEW

The concept of appropriate social contract for artisanal and small-scale mining(ASM) emerged amid calls for more humane working conditions for this cadre of miners, whose contribution to the alleviation of poverty especially in the developed nations of the world has been recognized by the United Nations. The sector which is a form of subsistence mining provides a direct or indirect livelihood for over 100 million people in the developing world out of which about 5 million are from Africa. Of particular note is the contribution of this sector to the world supply of strategic minerals such as coltan, diamond, gold etc. The presence of ASM is very often associated with challenges, including poor environmental, health and safety practices, the spread of communicable disease, heightened security risks to neighbouring communities and operations, child and forced labour, inequitable distribution of benefits in communities and an illegal trade in minerals. There is overwhelming consensus that the current worldwide natural resource constraints and the high rising cost of mineral investment and ecosystem pressures require new economic and social contract trajectories which should protect the interests of the artisanal and small-scale miners. These trajectories should address alternatives mining/processing methods and marketing of vital minerals in an environmentally friendly manner as well as improving the economic status of the miners. It is already the mainstream economy of the future, which is desirable to particularly support the rising African and population within the context of sustainable consumption and production patterns. The opportunity exists to make better use of the artisanal mining personnel towards the exploitation of natural resources and use mitigation and adaptation actions as a tool towards a more inclusive development path for the developing countries of Africa. Although concerted effort is being made by some organs of the United Nations, the civil society etc, what is essentially required by National governments Africa, is the adaption of a new Minerals and Mining Acts and institutional reforms/ frameworks and Fiscal Regimes which are in tandem with international best-practices and capable of adding socio-economic values to ASM activities