45 research outputs found
Pattern of distribution of reactive localised hyperplasia of the oral cavity in patients at a tertiary health institution in Nigeria
Background: Reactive localized hyperplastic lesions of the oral cavity (RHLs) are relatively common peripheral lesions which present as a range of clinically similar lesions at dental centers. Diagnosis can be challenging if dentists are unfamiliar with their clinicopathological across various populations.Objective: This study reviews the pattern of distribution of RHLs of the oral mucosa in a hospital- the Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Ile-Ife.Materials and methods: We reviewed 10 years data from the archives of the Department of Oral Maxillofacial Surgery and Oral Pathology, Obafemi Awolowo University, Nigeria. Information on RHLs were extracted and recorded on standardized data forms and analyzed using STATA.Results: The most common lesions were pyogenic granuloma (43.7%) and focal fibrous hyperplasia (39.7%), respectively. RHLs were found to be more frequent in women (66.7%) than men (33.3%). The most common locations of involvement was the gingivae (84.6%), and lesions were more common in the 9–29 year age group and the mean age was 37.7 (±21.1) years. The relationship between age group and reactive lesions was however not statistically significant.Conclusion: The major benefit of this study is an improved knowledge of the frequency and distribution of oral reactive le- sions in sub-Saharan Africa which may be highly beneficial when establishing a diagnosis and treatment plan in clinical practice.Keywords: Focal fibrous hyperplasia, oral mucosa, peripheral giant cell granuloma, peripheral ossifying fibroma, pyogenic gran- uloma, reactive hyperplasia
Scope, trends and opportunities for sociohydrology research in Africa: A bibliometric analysis
Socio-hydrology research is concerned with the understanding of how humanity interacts with water resources. The purpose of this study was to assess the disparity between global and African trends as well as developments in the research domain of socio-hydrology. From the viewpoint of a multitude of research themes, multi-author collaborations between African and international researchers and the number of publications produced globally, the results reveal that the field of socio-hydrology is still underdeveloped and yet nascent. At a global level, the USA, China, and the Netherlands have the highest number of scientific publications, while in Africa, South Africa dominates, although these scientific publications are significantly much lower than the global output. The output of scientific publications on socio-hydrology research from Africa increased from 2016, with significant output reached in 2019. Water management and supply, hydrological modelling, flood monitoring as well as policies and decision-making, are some of the dominant themes found through keywords co-occurrence analysis. These main keywords may be considered as the foci of research in socio-hydrology. Although socio-hydrology research is still in the early stages of development in Africa, the cluster and emerging themes analysis provide opportunities for research in Africa that will underpin new frontiers of the research agenda encompassing topics such as the (1) impacts of climate change on socio-hydrology; (2) influence of socio-hydrology on water resources such as surface water and groundwater; (3) benefits of socio-hydrological models on river basins and (4) role of socio-hydrology in economic sectors such as agriculture. Overall, this study points to a need to advance socio-hydrology research in Africa in a bid to address pressing water crises that affect sustainable development as well as to understand the feedback mechanisms and linkages between water resources and different sectors of society.
Significance:• The field of socio-hydrology is still under-researched in Africa. • Limited research could be attributed to a lack of expertise, resources and data limitations.• Socio-hydrology research is likely to be strengthened through collaborations between Africa and other developed countries.• Existing gaps present opportunities to advance socio-hydrology research in Africa
Characteristics and long-term trends of heat stress for South Africa
Increasing air temperature coupled with high humidity due to ongoing climate change
across most parts of South Africa is likely to induce and intensify heat exposure, particularly in
densely populated areas. The adverse health implications, including heatstroke, are expected to
be common and more severe during extreme heat and heat wave events. The present study was
carried out to examine heat stress conditions and long-term trends in South Africa. The study aimed
to identify geographical locations exposed to elevated heat stress based on over two decades of
hourly ground-based data. Selected heat stress indicators were calculated based on Steadman’s
apparent temperature (AT in â—¦C). The trends in AT were assessed based on the non-parametric
Mann–Kendall (MK) trend test at 5% significance level. Positive trends were detected in 88% of the
selected weather stations except in Welkom-FS, Ficksburg-FS, Langebaanweg-WC, Lambertsbaai
Nortier-WC, Skukuza-MP, and Thabazimbi-LP. Approximately 47% of the detected positive trends
are statistically significant at 5% significant level. Overall, high climatological annual median
(ATmed) values (>32 â—¦C) were observed at 42 stations, most of which are in low altitude regions,
predominately along the coastlines. The hottest towns with ATmed values in the danger category
(i.e., 39–50 ◦C) were found to be Patensie-EC (41 ◦C), Pietermaritzburg-KZN (39 ◦C), Pongola-KZN
(39 â—¦C), Knysna-WC (39 â—¦C), Hoedspruit-LP (39 â—¦C), Skukuza-MP (45 â—¦C), and Komatidraai-MP
(44 â—¦C). The results provide insight into heat stress characteristics and pinpoint geographical locations
vulnerable to heat stress conditions at the community level in South Africa. Such information can be
useful in monitoring hotspots of heat stress and contribute to the development of local heat–health
adaptation plans.The Water Research Commission of South Africa.https://www.mdpi.com/journal/sustainabilitydm2022Geography, Geoinformatics and Meteorolog
Pattern of distribution of reactive localised hyperplasia of the oral cavity in patients at a tertiary health institution in Nigeria
Background: Reactive localized hyperplastic lesions of the oral cavity
(RHLs) are relatively common peripheral lesions which present as a
range of clinically similar lesions at dental centers. Diagnosis can be
challenging if dentists are unfamiliar with their clinicopathological
across various populations. Objective: This study reviews the pattern
of distribution of RHLs of the oral mucosa in a hospital- the Obafemi
Awolowo University Teaching Hospital Complex (OAUTHC), Ile-Ife.
Materials and methods: We reviewed 10 years data from the archives of
the Department of Oral Maxillofacial Surgery and Oral Pathology,
Obafemi Awolowo University, Nigeria. Information on RHLs were extracted
and recorded on standardized data forms and analyzed using STATA.
Results: The most common lesions were pyogenic granuloma (43.7%) and
focal fibrous hyperplasia (39.7%), respectively. RHLs were found to be
more frequent in women (66.7%) than men (33.3%). The most common
locations of involvement was the gingivae (84.6%), and lesions were
more common in the 9\u201329 year age group and the mean age was 37.7
(\ub121.1) years. The relationship between age group and reactive
lesions was however not statistically significant. Conclusion: The
major benefit of this study is an improved knowledge of the frequency
and distribution of oral reactive lesions in sub-Saharan Africa which
may be highly beneficial when establishing a diagnosis and treatment
plan in clinical practice. DOI:
https://dx.doi.org/10.4314/ahs.v19i1.45 Cite as: Soyele OO, Ladeji AM,
Adebiyi KE, Adesina OM, Aborisade AO, Olatunji AS, et al. Pattern of
distribution of reactive localised hyperplasia of the oral cavity in
patients at a tertiary health institution in Nigeria. Afri Health Sci.
2019;19(1). 1687-1694. https://dx.doi. org/10.4314/ ahs. v19i1.4
Hydrological drought assessment based on the standardized streamflow index : a case study of the three Cape provinces of South Africa
Global impacts of drought conditions pose a major challenge towards the achievement
of the 2030 Sustainable Development Goals. As a result, a clarion call for nations to take actions
aimed at mitigating the adverse negative effects, managing key natural resources and strengthening
socioeconomic development can never be overemphasized. The present study evaluated hydrological
drought conditions in three Cape provinces (Eastern, Western and Northern Cape) of South Africa,
based on the Standardized Streamflow Index (SSI) calculated at 3- and 6-month accumulation periods
from streamflow data spanning over the 3.5 decades. The SSI features were quantified by assessing
the corresponding annual trends computed by using the Modified Mann–Kendall test. Drought
conditions were also characterized in terms of the duration and severity across the three Cape
provinces. The return levels of drought duration (DD) and drought severity (DS) associated with
2-, 5-, 10-, 20- and 50-year periods were estimated based on the generalized extreme value (GEV)
distribution. The results indicate that hydrological drought conditions have become more frequent
and yet exhibit spatial contrasts throughout the study region during the analyzed period. To this end,
there is compelling evidence that DD and DS have increased over time in the three Cape provinces.
Return levels analysis across the studied periods also indicate that DD and DS are expected to be
predominant across the three Cape provinces, becoming more prolonged and severe during the
extended periods (e.g., 20- and 50-year). The results of the present study (a) contribute to the scientific
discourse of drought monitoring, forecasting and prediction and (b) provide practical insights on
the nature of drought occurrences in the region. Consequently, the study provides the basis for
policy- and decision-making in support of preparedness for and adaptation to the drought risks in
the water-linked sectors and robust water resource management. Based on the results reported in
this study, it is recommended that water agencies and the government should be more proactive in
searching for better strategies to improve water resources management and drought mitigation in
the region.Water Research Commission of South Africahttps://www.mdpi.com/journal/waterdm2022Geography, Geoinformatics and Meteorolog
Drought risk analysis in the Eastern Cape Province of South Africa : the copula lens
This research study was carried out to investigate the characteristics of drought based on the
joint distribution of two dependent variables, the duration and severity, in the Eastern Cape Province,
South Africa. The drought variables were computed from the Standardized Precipitation Index for
6- and 12-month accumulation period (hereafter SPI-6 and SPI-12) time series calculated from the
monthly rainfall data spanning the last five decades. In this context, the characteristics of climatological
drought duration and severity were based on multivariate copula analysis. Five copula functions
(from the Archimedean and Elliptical families) were selected and fitted to the drought duration
and severity series in order to assess the dependency measure of the two variables. In addition,
Joe and Gaussian copula functions were considered and fitted to the drought duration and severity
to assess the joint return periods for the dual and cooperative cases. The results indicate that the
dependency measure of drought duration and severity are best described by Tawn copula families.
The dependence structure results suggest that the study area exhibited low probability of drought
duration and high probability of drought severity. Furthermore, the multivariate return period
for the dual case is found to be always longer across all the selected univariate return periods.
Based on multivariate analysis, the study area (particularly Bu alo City, OR Tambo and Alfred Zoo
regions) is determined to have higher/lower risks in terms of the conjunctive/cooperative multivariate
drought risk (copula) probability index. The results of the present study could contribute towards
policy and decision making through e.g., formulation of the forward-looking contingent plans for
sustainable management of water resources and the consequent applications in the preparedness for
and adaptation to the drought risks in the water-linked sectors of the economy.The Water Research Commission, South Africahttp://www.mdpi.com/journal/wateram2021Geography, Geoinformatics and MeteorologyUP Centre for Sustainable Malaria Control (UP CSMC
Assessing industrial development influence on land use/cover drivers and change detection for West Bank East London, South Africa
South Africa’s nationwide socio-economic industrial development zone drive focuses on alleviating of the apartheid social ills legacy. To ensure sustainable industrial ecological development, land-cover monitoring is needed though limited attention has been accorded. This study, aimed at assessing the influence of East London Industrial Development Zone (ELIDZ) on land-use/land-cover (LULC) drivers and detecting LULC changes for 15 years over the West Bank East London. An integration of remote sensing with qualitative approaches was adopted to provide robust temporal and spatial LULC change analysis. Object-based classification was performed on the satellite images for 1998, 2007 and 2013. Normalised Difference Vegetation Index (NDVI) and Normalised Difference Built-up Index (NDBI) complemented and validated observed land cover changes. The study reveals that industrial development has been a key driver for land-use changes in West Bank. The classification indicated that vegetation (5.97%) and bare land (-9.06%) classes had the highest percentage increase and decrease respectively. Water (0.02%) and bare land (-0.6%) classes had the lowest annual rate of change. Built-up and bare land classes varied considerably. An overall land-cover classification mean accuracy assessment of 97.24% and a mean Kappa coefficient of 0.95 were attained for the entire study period. This study offers the value of integrated methods in monitoring land-cover change to enhance informed decision-making especially in rapidly changing landscapes for conservation purposes.This manuscript stems from the corresponding authors’ postgraduate study and who performed most of the experiments.The University of Pretoria and the United State Geological Survey (USCS).http://www.ripublication.comam2019Geography, Geoinformatics and Meteorolog
Partnership for International Development:Finland-Nigeria Conference on Climate, Food, Health and Entrepreneurship
A joint collaboration between the Arctic Centre of the University of Lapland, Finland and the Federal Institute of Industrial Research, Oshodi, Lagos, Nigeria was organised as a hybrid conference on several topics that are related to climate, food, health and entrepreneurship. The utilisation of natural resources in both regions is an important theme in meeting the sustainable development goals agenda. The topics discussed were multidisciplinary, they include Nigerian indigenous foods, bioeconomy, circular economy, nutrition, health, innovation and entrepreneurship under four themes (Climate, Food, Health and Entrepreneurship). There were dignitaries from Finland and Nigeria. The presenters are researchers from Nigerian universities (University of Ibadan, University of Abuja and Eko university, Lagos), Nigerian Federal Institute of Industrial research centre and from the Finnish side we have the university of Lapland, Rovaniemi, University of Oulu, Oulu and the Centria University of Applied Sciences, Kokkola. The topics discussed will serve as training materials for students and learners, the discussion focussed on research opportunities for institutions in both countries. The experts from both countries will continue to dialogue on the possibility of promoting common topics as research agenda in these important areas with the possibilities of creating more jobs
Variability of satellite derived phenological parameters across maize producing areas of South Africa
Changes in phenology can be used as a proxy to elucidate the short and long term trends
in climate change and variability. Such phenological changes are driven by weather and climate
as well as environmental and ecological factors. Climate change affects plant phenology largely
during the vegetative and reproductive stages. The focus of this study was to investigate the changes
in phenological parameters of maize as well as to assess their causal factors across the selected
maize-producing Provinces (viz: North West, Free State, Mpumalanga and KwaZulu-Natal) of South
Africa. For this purpose, five phenological parameters i.e., the length of season (LOS), start of season
(SOS), end of season (EOS), position of peak value (POP), and position of trough value (POT) derived
from the MODIS NDVI data (MOD13Q1) were analysed. In addition, climatic variables (Potential
Evapotranspiration (PET), Precipitation (PRE), Maximum (TMX) and Minimum (TMN) Temperatures
spanning from 2000 to 2015 were also analysed. Based on the results, the maize-producing Provinces
considered exhibit a decreasing trend in NDVI values. The results further show that Mpumalanga
and Free State Provinces have SOS and EOS in December and April respectively. In terms of the
LOS, KwaZulu-Natal Province had the highest days (194), followed by Mpumalanga with 177 days,
while NorthWest and Free State Provinces had 149 and 148 days, respectively. Our results further
demonstrate that the influences of climate variables on phenological parameters exhibit a strong
space-time and common covariate dependence. For instance, TMN dominated in North West
and Free State, PET and TMX are the main dominant factors in KwaZulu-Natal Province whereas
PRE highly dominated in Mpumalanga. Furthermore, the result of the Partial Least Square Path
Modeling (PLS-PM) analysis indicates that climatic variables predict about 46% of the variability
of phenology indicators and about 63% of the variability of yield indicators for the entire study
area. The goodness of fit index indicates that the model has a prediction power of 75% over the
entire study area. This study contributes towards enhancing the knowledge of the dynamics in the phenological parameters and the results can assist farmers to make the necessary adjustment in
order to have an optimal production and thereby enhance food security for both human and livestock.The Department of Science
and Technology (DST) and The National Research Foundation (NRF).http://www.mdpi.com/journal/sustainabilityam2018Animal and Wildlife SciencesGeography, Geoinformatics and MeteorologyPlant Production and Soil Scienc
Environmental factors and population at risk of malaria in Nkomazi municipality, South Africa
OBJECTIVE : Nkomazi local municipality of South Africa is a high-risk malaria region with an
incidence rate of about 500 cases per 100 000. We examined the influence of environmental factors
on population (age group) at risk of malaria.
methods R software was used to statistically analyse data. Using remote sensing technology, a Landsat
8 image of 4th October 2015 was classified using object-based classification and a 5-m resolution. Spot
height data were used to generate a digital elevation model of the area. RESULTS : A total of 60 718 malaria cases were notified across 48 health facilities in Nkomazi municipality between January 1997 and August 2015. Malaria incidence was highly associated with
irrigated land (P = 0.001), water body (P = 0.011) and altitude ≤400 m (P = 0.001). The multivariate
model showed that with 10% increase in the extent of irrigated areas, malaria risk increased by almost
39% in the entire study area and by almost 44% in the 2-km buffer zone of selected villages. Malaria
incidence is more pronounced in the economically active population aged 15–64 and in males. Both
incidence and case fatality rate drastically declined over the study period. CONCLUSION : A predictive model based on environmental factors would be useful in the effort towards malaria elimination by fostering appropriate targeting of control measures and allocating of resources.This study was supported by the EU project ‘Quantifying
Weather and Climate Impacts on health in developing
countries’, an European Commission’s Seventh Framework
Research Programme by providing a 2-year student
bursary to the primary author. We acknowledge the support
of the University of Pretoria, Centre for Sustainable
Malaria Control and of the Earth and Atmospheric
Remote Sensing Research Group, University of Pretoria.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-31562017-05-31hb2016Centre for Environmental StudiesCentre for Geoinformation ScienceGeography, Geoinformatics and Meteorolog