TOWARDS EFFECTIVE PLANNING, DESIGN AND MONITORING OF DAMS IN NIGERIA

Besides serving as a center of tourist attraction, creating jobs for the unemployed, a rich source of fish and a fallback in times of drought, a dam also creates electricity from nothing other than the falling of water through its turbines. In Nigeria, like in many other parts of the world, dam projects are often seen as key to economic solution through hydroelectric power supply. The technology of dam construction in Nigeria is still experimental. There are so many unknown factors in dam design, construction and operation that may affect dam’s safety and performance. Relying on field experience from various parts of Nigeria, this paper examines the essential details necessary for consideration in dam planning and design using the complete and accurate information on the important variables such as technical, environmental, socio-cultural, economic or cultural factors. The results of these examined factors indicated that most of dam projects in Nigeria are not properly planned. The basic planning flaws include hydrologic, environmental and social factors which are seen by dam builders as obstacles to be ignored, covered up or surrogated to engineering in the project planning. Incorrect calculation of flood flows has lead to dam failures and reservoir siltation has drastically reduced the lifespan of dams, making one to conclude that the entire concept of dam safety as a design criterion is a new one. It appears that Nigeria will have to live with these flaws and some of these cost for sometimes to come. There is, therefore, the need for us to reduce these through proper planning, design and monitoring of our dams. It is recommended that a comprehensive dam safety study of all old dams (i.e. ≥ 20 years) be carried out. &nbsp

The Influence of Organizational External Factors on Construction Risk Management among Nigerian Construction Companies

Background: Substantial empirical research has shown conflicting results regarding the influence of organizational external factors on construction risk management, suggesting the necessity to introduce a moderator into the study. The present research confirmed whether rules and regulations matter on the relationships between organizational external factors and construction risk management. Methods: Based on discouragement and organizational control theory, this research examined the effects of organizational external factors and rules and regulations on construction risk management among 238 employees operating in construction companies in Abuja and Lagos, Nigeria. A personally administered questionnaire was used to acquire the data. The data were analyzed using partial least squares structural equation modeling. Results: A significant positive relationship between organizational external factors and construction risk management was asserted. This study also found a significant positive relationship between rules and regulations and construction risk management. As anticipated, rules and regulations were found to moderate the relationship between organizational external factors and construction risk management, with a significant positive result. Similarly, a significant interaction effect was also found between rules and regulations and organizational external factors. Implications of the research from a Nigerian point of view have also been discussed. Conclusion: Political, economy, and technology factors helped the construction companies to reduce the chance of risk occurrence during the construction activities. Rules and regulations also helped to lessen the rate of accidents involving construction workers as well as the duration of the projects. Similarly, the influence of the organizational external factors with rules and regulations on construction risk management has proven that most of the construction companies that implement the aforementioned factors have the chance to deliver their projects within the stipulated time, cost, and qualities, which can be used as a yardstick to measure a good project

Open intramedullary nailing for segmental long bone fractures: an effective alternative in a resource restricted environment

Background: Closed, locked intramedullary nailing has been accepted as the gold standard in the care of femoral fractures, with reported union rates as high as 98–100%. Closed, locked intramedullary nailing often requires expensive equipment which is a challenge in developing countries. Segmental long bone fractures are often a result of high‑energy trauma and hence often associated with a lot of injuries to the surrounding soft tissues. This consequently results in higher rates of delayed or nonunion. This study was proposed to review the outcome of management of segmental fractures with locked intramedullary nails, using an open method of reduction. Methods: A retrospective analysis was made of data obtained from all segmental long bone fractures treated with intramedullary nailing over a 1‑year period. Records were retrieved from the folders of patients operated on from January 2011 to  December 2011. Patients were followed up for a minimum of 1 year after the surgery. Results: We managed a total of 12 segmental long bone fractures in 11 patients. Eight of the 12 fractures were femoral fractures and 10 of the fractures were closed fractures. All but one fracture (91.7%) achieved union within 4 months with no major complications.Conclusions: Open method of locked intramedullary nailing achieves satisfactory results when used for the management of long bone fractures. The method can be used for segmental fractures of the humerus, femur, and tibia, with high union rates. This is particularly useful in low‑income societies where the use of intraoperative imaging may be unavailable or unaffordable. It gives patients in such societies, a chance for comparable outcomes in terms of union rates as well as avoidance of major complications. Larger prospective studies will be necessary to conclusively validate the efficacy of this fixation method in this environment.Keywords: Locked intramedullary nailing, open reduction, segmental fracture

Perception about being an aged person in South-Western Nigeria

This paper investigates the perception about being an aged person in SouthWestern Nigeria. 594 aged persons were interviewed through questionnaire administration in Lagos and Oyo states of South-western Nigeria. The univariate, bivariate and One-way Analysis of variance (F-ratios) were employed in the analyses of this research. The major findings of this study are: firstly, the univariate and bivariate results indicate that there is low-perception about being an aged person. Secondly, One-way Analysis of variance (F-ratios) show that the study location, age category, means of livelihood; and usual place of residence (Oyo and Lagos state rural settings) have significant influences on perception about being an aged person in South-Western Nigeria. Thus, the paper recommends the following: firstly, that aged persons from Lagos state who are 50-79 years should begin to admit from now that they are ‘elderly people’ despite the fact that some of them are retired and still physically active. Secondly, the salary earners who are still working as well as Lagos-rural dwellers should urgently assume their roles as elders both in the families and in larger Nigerian society

Building sustainability in the construction industry through firm capabilities, technology and business innovativeness: empirical evidence from Malaysia

While the identification of the drivers of social sustainability in construction firms has remained one of the popular topics in the literature, many questions about these drivers remain unanswered, especially in the context of the developing countries. This study empirically determines some organizational internal drivers influencing the social sustainability performance in construction firms. To achieve this, we developed a conceptual model and tested on a sample of registered and active large construction firms from the Malaysian Construction Industry Development Board, using partial least-squares structural equation modelling for analysis. The study reveals that organizational internal drivers could trigger social sustainability performance. However, our analysis shows that organizational capabilities – complex tangible and intangible resources that are controlled by a firm through certain organizational practices and which enable it to implement value-creating strategies-partially mediates the relationship between these drivers and social sustainability. While few limitations of this study include the fact that the data used are the subjective opinions of the top officials who responded to the survey, our findings reveal that construction firms with efficient resource capabilities tend to adopt more sustainability in project delivery. This study contributes to the ongoing discussion on the important factors for social sustainability in construction

The first-line antituberculosis drugs, and their fixed-dose combination induced abnormal sperm morphology and histological lesions in the testicular cells of male mice

Rifampicin (RIF), Isoniazid (INH), Ethambutol (EMB), Pyrazinamide (PZA), and/or their fixed-dose combination (FDC) are extensively prescribed in the cure of Tuberculosis (TB) globally. In spite of the beneficial effect, these drugs are capable of inducing cellular toxicity. Existing information on the genotoxic effects of the first-line anti-TB drugs is limited and contentious. Herein, we evaluated the reproductive genotoxicity of RIF, INH, EMB, PZA, and their FDC utilizing the mouse sperm morphology assay. Histological examination of the testes of exposed mice was also performed. Male Swiss albino mice (11–13 weeks old) were intraperitoneally exposed for 5 consecutive days to each of the anti-TB drugs at four different doses of 6.25, 12.5, 25, and 50 mg/kg bw of PZA; 2.5, 5.0, 10, and 20 mg/kg bw of RIF; 1.25, 2.5, 5.0 and 10 mg/kg bw of INH; 3.75, 7.5, 15 and 30 mg/kg bw of EMB; and 7, 14, 28 and 56 mg/kg bw of FDC corresponding respectively to ×0.25, ×0.5, ×1 and ×2.0 of the standard daily dose. In comparison with the negative control (normal saline), there was no significant difference in the testicular weight and organo-somatic index of exposed mice. There was an increase (p > 0.05) in the frequency of abnormal spermatozoa at most of the tested doses of each drug and a dose-dependent decrease with the FDC. Each of the anti-TB drugs except the FDC induced pathological lesions in the testes. These findings suggest that the individual first-line anti-TB drug unlike the FDC has the potential to provoke testicular anomalies in male mice

World Health Organization Discontinues Its Drinking-Water Guideline for Manganese

Background: The World Health Organization (WHO) released the fourth edition of Guidelines for Drinking-Water Quality in July 2011. In this edition, the 400-µg/L drinking-water guideline for manganese (Mn) was discontinued with the assertion that because “this health-based value is well above concentrations of manganese normally found in drinking water, it is not considered necessary to derive a formal guideline value.