43 research outputs found
Vulnerability mapping as a tool to foster groundwater protection in areas subject to rapid population expansion: The case study of Abuja Federal Capital Territory (Nigeria)
Study region
Abuja Federal Capital Territory (FCT; Nigeria).
Study Focus
Rapid population growth has led to significant land use changes, with potential negative impacts on groundwater quality. However, the lack of understanding of hydrogeological settings, often due to limited data availability, is one of the main obstacles to sound planning in rapidly changing environments. To assess the specific groundwater vulnerability to nitrate, a DRASTIC-LU model was applied, combining the land use data from the last 20 years with the intrinsic aquifer vulnerability. This study represents the first attempt to assess aquifer vulnerability in the region.
New hydrogeological insights for the region
Results show that the Abuja FCT has been affected by a dramatic change in land use with an increase in urbanized and agricultural areas and may induce nitrate contamination in groundwater. Currently, several wells in the region are showing nitrate concentrations that exceed the statutory limit for drinking purposes. The comparison of DRASTIC-LU results with nitrate concentrations shows that the highest concentrations are found in urban/peri-urban areas. Although fertilizers are generally considered to be the main source of nitrate contamination, these results suggest a possible mixed (urban and agricultural) pollution origin. This investigation therefore represents a starting point for future nitrate monitoring assessments and for supporting decision makers with adequate information for urban planning in view of the expected population growth in the area
Assessment of Foundation Instability Using Integrated Geotechnical and Geophysical Techniques: A Case Study of Giza, Keana LGA, Nasarawa State, North Central Nigeria
Engineering structures such as buildings, in Giza community (central Nigeria) have developed severe cracks, undergone differential settlement, and failed in some parts. These have been a disturbing situation to its inhabitants. Integrated geophysical, geotechnical, and hydrogeological techniques were employed to investigate the causes of this menace. Vertical Electric Sounding (VES) was used to delineate the subsurface geo-electric layers. Soil samples were analyzed for grain-size distribution, Atterberg Limit, moisture content, specific gravity, compaction, coefficient of permeability, and undrainedtriaxial test. Static water level measurements were carried out during wet and dry seasons to establish the zone of groundwater fluctuation. VES results revealed that foundations within the cracked zone are underlain by incompetent, low resistivity (2.77 – 24.8 Ωm) saturated clay (0.5-3.1m thick). The non-cracked zone is underlain by moderately competent, clayey sands (3.5-6.9m thick). Geotechnical results of the cracked zone revealed high plasticity (29-51%), high moisture content (10.11-12.02%,), and low permeability (4.26×10-5-5.36×10-7m/sec) which impedes drainage. Maximum dry density ranges from 1.76 – 1.88g/m3 with corresponding optimum moisture content of 10.11 – 12.02%. Cohesion contributes more to the shear strength than angle of internal friction in the cracked zone, compared to the non-cracked zone, which shear strength is controlled by both. The groundwater fluctuation zone was found to be 1.1-6.2m and within the clay layer. The shallow zone of fluctuation saturates clays under foundation making it highly plastic. The soils experiences swelling and shrinking as water level rises and falls, which cause buildings to heave, crack, or settles differentially leading to failures
Patterns of Antimicrobial Use in a Specialized Surgical Hospital in Southeast Nigeria: Need for a Standardized Protocol of Antimicrobial Use in the Tropics
Background: Antimicrobial resistance remains a growing global health menace. One of the key actions to curb this menace by the World Health Organization is antimicrobial stewardship (AMS). A prescription protocol is one of the cost‑effective AMS interventions in surgery. This study determines the patterns of antimicrobial usage in a hospital specialized in orthopedic and plastic surgeries care in Nigeria.
Methods: A cross-sectional survey was carried out at National Orthopaedic Hospital Enugu, a tertiary hospital specialized in orthopedic and plastic surgeries in Southeast Nigeria in May 2019. All the inpatients were included in the study. A standardized tool for point prevalence survey was used to collect data. Data were analyzed using Epi Info version 7.2.4.
Results: A total of 127 inpatients participated in the survey with 387 antimicrobial encounters. The most common reasons for antimicrobial use were for the treatment of community-acquired infections (65.0%) and prophylaxis (29.4%). The decision for their use was made majorly on an empirical basis (92.4%). The reasons for antimicrobial prescriptions were documented in the majority (97.5%) of the cases and stop review dates in all (100%) of the prescriptions. Ceftriaxone (25.7%), tinidazole (21.9%), and metronidazole (14.6%) were the commonest antimicrobials prescribed among the patients.
Conclusion: Orthopedic and plastic surgery practices require tailored prophylactic antibiotic regimens in the tropics due to peculiarities of both the specialties and the subregion. The claim that existing protocols in the temperate regions may apply in the tropics has been questioned due to the microbial profile on the tropics.
Keywords: Antimicrobial protocol in surgery, antimicrobial resistance, antimicrobial stewardship, prophylactic antibiotic
Immunological insights into COVID-19 in Southern Nigeria
Introduction: One of the unexpected outcomes of the COVID-19 pandemic was the relatively low levels of morbidity and mortality in Africa compared to the rest of the world. Nigeria, Africa's most populous nation, accounted for less than 0.01% of the global COVID-19 fatalities. The factors responsible for Nigeria's relatively low loss of life due to COVID-19 are unknown. Also, the correlates of protective immunity to SARS-CoV-2 and the impact of pre-existing immunity on the outcome of the COVID-19 pandemic in Africa are yet to be elucidated. Here, we evaluated the natural and vaccine-induced immune responses from vaccinated, non-vaccinated and convalescent individuals in Southern Nigeria throughout the three waves of the COVID-19 pandemic in Nigeria. We also examined the pre-existing immune responses to SARS-CoV-2 from samples collected prior to the COVID-19 pandemic.
Methods: We used spike RBD and N- IgG antibody ELISA to measure binding antibody responses, SARS-CoV-2 pseudotype assay protocol expressing the spike protein of different variants (D614G, Delta, Beta, Omicron BA1) to measure neutralizing antibody responses and nucleoprotein (N) and spike (S1, S2) direct ex vivo interferon gamma (IFNγ) T cell ELISpot to measure T cell responses.
Result: Our study demonstrated a similar magnitude of both binding (N-IgG (74% and 62%), S-RBD IgG (70% and 53%) and neutralizing (D614G (49% and 29%), Delta (56% and 47%), Beta (48% and 24%), Omicron BA1 (41% and 21%)) antibody responses from symptomatic and asymptomatic survivors in Nigeria. A similar magnitude was also seen among vaccinated participants. Interestingly, we revealed the presence of preexisting binding antibodies (N-IgG (60%) and S-RBD IgG (44%)) but no neutralizing antibodies from samples collected prior to the pandemic.
Discussion: These findings revealed that both vaccinated, non-vaccinated and convalescent individuals in Southern Nigeria make similar magnitude of both binding and cross-reactive neutralizing antibody responses. It supported the presence of preexisting binding antibody responses among some Nigerians prior to the COVID-19 pandemic. Lastly, hybrid immunity and heterologous vaccine boosting induced the strongest binding and broadly neutralizing antibody responses compared to vaccine or infection-acquired immunity alone
Climate Variation-Induced Migration, Land Conflicts, and Security Situation in Nigeria
Climate variation largely impacts migration in with the capacity to worsen conflict and security situations in parts of Africa, Nigeria in particularly, already facing security threats from the activities of sedentary and nomadic pastoral farmer’s interaction. Increasing variations in rainfall patterns significantly impact the migration patterns of vulnerable households and constitute a risk factor to their livelihoods. For effective adaptation plan and sustainable livelihood decision that has climate resilient future, there is need for better understanding of the conflict and security implications of climate variation. This paper, therefore, interrogates the nexus between climate variation and migration, as well as the impact of this nexus on conflicts and security of lives and properties in Nigeria. Using critical analysis and qualitative methodology, the study establishes that migration settlement policies that fail to define the rights and duties of settlers and those of indigenes of any particular community, create loopholes for the reification of identities and identity-induced crisis. The conclusion of the paper is that migration issues resulting from climate variation have not been adequately addressed to involve all stakeholders. There is the need to harvest environmental impact assessment data of climate variation to guide the provision of alternative options to climate-related emergencies across Nigeria
コトナル リュウド ノ スナ ニ オケル リュウドウ スベリ ノ ハッセイ ウンドウ ヨソク
京都大学0048新制・課程博士博士(理学)甲第12106号理博第3000号新制||理||1447(附属図書館)23942UT51-2006-J101京都大学大学院理学研究科地球惑星科学専攻(主査)教授 佐々 恭二, 教授 千木良 雅弘, 教授 橋本 学学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDA
THE ROLES OF ICT DEVELOPMENT IN OPEN AND DISTANCE EDUCATION: ACHEIVEMENTS, PROSPECTS AND CHALLENGES
The promises of information and communication technologies (ICT) have driven e-learning in transforming open distance education and thereby advancing the knowledge economy that rested on three arguments: E-learning could expand and widen access to tertiary education and learning; improve the quality of education; and reduce its cost. This article evaluates these three promises based on existing data and evidence. It concludes that the reality has not matched the promises so far in terms of pedagogic innovation. This does not mean that ICT development has not produced any significant positive results in improving the overall learning (and teaching) experience in the institutions and societies where it is implemented. That implies that what will help further to identify the new challenge. ICT development faces will be further research. Obstacles and problems of ICT that could have affected the open educational resource initiatives are yet to be established. The first section of the paper recalls some of the proposed values of e-learning. The second section compares achievements so far and suggests that e-learning could be only at an early stage of realising educational innovation aspirations. The third section highlights the challenges of future developments in e-learning
THE ROLES OF ICT DEVELOPMENT IN OPEN AND DISTANCE EDUCATION: ACHEIVEMENTS, PROSPECTS AND CHALLENGES
The promises of information and communication technologies (ICT) have driven e-learning in transforming open distance education and thereby advancing the knowledge economy that rested on three arguments: E-learning could expand and widen access to tertiary education and learning; improve the quality of education; and reduce its cost. This article evaluates these three promises based on existing data and evidence. It concludes that the reality has not matched the promises so far in terms of pedagogic innovation. This does not mean that ICT development has not produced any significant positive results in improving the overall learning (and teaching) experience in the institutions and societies where it is implemented. That implies that what will help further to identify the new challenge. ICT development faces will be further research. Obstacles and problems of ICT that could have affected the open educational resource initiatives are yet to be established. The first section of the paper recalls some of the proposed values of e-learning. The second section compares achievements so far and suggests that e-learning could be only at an early stage of realising educational innovation aspirations. The third section highlights the challenges of future developments in e-learning
Violent Conflicts as an impediment to the Achievement of Millennium Development Goals in Africa.
Abstract This paper aims to stimulate a debate on how Violent Conflict (VC) is obstructing the success of Millennium Development Goals (MDGs). It briefly examines progress with the MDGs in Africa using officially published United Nation (UN) Reports and global MDG monitoring information. It also provides readers with a preliminary exposition on how violent conflicts pose the greatest challenges to progress with achieving the MDGs. It argues that violent conflict makes chronic poverty even worse – from household to national levels. The paper warns that many countries in Africa will fall far behind in attaining the MDGs by the targeted date of 2015 unless African states and regional institutions such as the African Union can put a decisive end to the current conflicts and address the threat of new conflicts. Having presented comparative evidence from various countries (those on track to meet the MDGs and those lagging behind), the significance of conflict prevention, conflict resolution and peace building in increasing the likelihood of Africa’s achieving the MDGs within the timeframe were highlighted. Highlighting the critical importance of strengthening the link between durable peace and sustainable development, it was concluded that the MDGs, as a framework for policy, programs and international partnerships to reduce poverty, must explicitly articulate how to end violent conflict and support war-torn countries (and those emerging from conflict) as a matter of priority and that they must receive special consideration. Key words: Millennium Development Goals, Violent Conflict, Poverty, Regional Institutions, Conflict Resolution, Peace Building, Sustainable Development, International Partnerships