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Hydrogeochemical Model and Water Quality of Groundwater in the Granito-Basaltic Fractured Rock Aquiferous Formations in Bafoussam, West Region-Cameroon  [PDF]
R. A. Akoachere, T. A. Eyong, M. O. Eduvie, S. E. Egbe, O. O. Yaya, M. O. Nwude
Journal of Water Resource and Protection (JWARP) , 2018, DOI: 10.4236/jwarp.2018.1011068
Abstract: This study determined the hydrogeochemical model of groundwater and groundwater domestic-agro-industrial quality in Bafoussam using hydrogeochemical tools and physicochemical parameters: Ionic ratios, Gibbs diagrams, Piper diagrams, Durov diagrams and water quality indices. From physicochemical parameters; pH ranged from, 4.47 - 7.84; EC, 10 - 820 μS/cm; Temperature, 22.3°C - 29.5°C and TDS, 6.7 - 549.4 mg/L. The major ions fell below WHO acceptable limits. The sequences of major ionic abundance are: Ca2+ > Mg2+ > K+ > Na+ > NH+4, HCO-3 > Cl- > SO2-4 > NO3 > HPO2-4. Recharge by atmospheric precipitation, ion-exchange and simple dissolution processes are responsible for groundwater character, ionic content resulted from ion exchange and rock-weathering. Water types are Ca-HCO3 and Ca-Cl Hydrogeochemical facies are Ca-Mg-Cl-SO4 and Ca-Mg-HCO3. Domestic water quality was determined by use of pH, electrical Conductivity EC, total dissolved solids TDS, total Hardness HT and water quality index WQI. WQI values ranged from 0 - 42.09 and HT 67.89 - 339.01 indicating that water is of good domestic quality. Agro-industrial suitability of groundwater was determined using, sodium adsorption ratio SAR, permeability index PI, Magnesium adsorption ratio MAR, percent sodium %Na, Kelly’s ratio KR and Residual sodium carbonate RSC and Wilcox diagram; From irrigational water suitability parameters, SAR values ranged from 0.01 - 0 05; %Na 3.69 - 15.50; KR 0.005 - 0.023; PI 1.04 - 67.98; MAR 2.89 - 55.27; RSC -5.22 to -0.44 and Wilcox diagram indicate that inorganic groundwater content in the study area is excellent-good for irrigation; this is of significance since Bafoussam a major agroindustrial zone in Cameroon and Central Africa is in the process of developing large scaled irrigation based agricultural projects dependent on use of surface and groundwater. Recharge from precipitation exchanges ions with the weathered country rocks and mixes with regional flow in a generally south-east north-westerly direction by piston flow in the granito-basaltic aquiferous formations in Bafoussam. There is need for detailed studies to determine aquifer
Prevalence and causes of blindness at a tertiary hospital in Douala, Cameroon
Eballé AO, Mvogo CM, Koki G, Nyouma Moune E, Teutu C, Ellong A, Bella AL
Clinical Ophthalmology , 2011, DOI: http://dx.doi.org/10.2147/OPTH.S23064
Abstract: evalence and causes of blindness at a tertiary hospital in Douala, Cameroon Original Research (2753) Total Article Views Authors: Eballé AO, Mvogo CM, Koki G, Nyouma Moune E, Teutu C, Ellong A, Bella AL Published Date September 2011 Volume 2011:5 Pages 1325 - 1331 DOI: http://dx.doi.org/10.2147/OPTH.S23064 André Omgbwa Eballé1,4, C me Ebana Mvogo1,3, Godefroy Koki2, Nyouma Mounè3, Cyrille Teutu5, Augustin Ellong2,3, Assumpta Lucienne Bella2,4 1Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon; 2Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon; 3General Hospital of Douala, Ophthalmology Unit, Douala, Cameroon; 4Cameroon National Blindness Control Programme, Ministry of Public Health, Yaoundé, Cameroon; 5Higher Institute of Health Sciences, Mountain University, Banganté, Cameroon Purpose: The aim of this study was to determine the prevalence and causes of bilateral and unilateral blindness in the town of Douala and its environs based on data from the ophthalmic unit of a tertiary hospital in Douala. Methods: We conducted a retrospective epidemiological survey of consultations at the eye unit of the Douala General Hospital over the last 20 years (from January 1, 1990 to December 31, 2009). Results: Out of the 1927 cases of blindness, 1000 were unilateral, corresponding to a hospital prevalence of 1.84% and 927 cases were bilateral, corresponding to a hospital prevalence of 1.71%. No statistically significant difference was noted between the two (P = 0.14). The leading causes of bilateral blindness were cataract (50.1%), glaucoma (19.7%), and diabetic retinopathy (7.8%) while the leading causes of unilateral blindness were cataract (40.4%), glaucoma (14.1%), and retinal detachment (9.1%). Cataract (51.2%), cortical blindness (16.3%), and congenital glaucoma (10%) were the leading causes of bilateral blindness in children aged less than 10 years. Conclusion: Blindness remains a public health problem in the Douala region with a hospital prevalence which is relatively higher than the national estimate given by the National Blindness Control Program.
Prevalence and causes of blindness at a tertiary hospital in Douala, Cameroon  [cached]
Eballé AO,Mvogo CM,Koki G,Nyouma Moune E
Clinical Ophthalmology , 2011,
Abstract: André Omgbwa Eballé1,4, C me Ebana Mvogo1,3, Godefroy Koki2, Nyouma Mounè3, Cyrille Teutu5, Augustin Ellong2,3, Assumpta Lucienne Bella2,41Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon; 2Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon; 3General Hospital of Douala, Ophthalmology Unit, Douala, Cameroon; 4Cameroon National Blindness Control Programme, Ministry of Public Health, Yaoundé, Cameroon; 5Higher Institute of Health Sciences, Mountain University, Banganté, CameroonPurpose: The aim of this study was to determine the prevalence and causes of bilateral and unilateral blindness in the town of Douala and its environs based on data from the ophthalmic unit of a tertiary hospital in Douala.Methods: We conducted a retrospective epidemiological survey of consultations at the eye unit of the Douala General Hospital over the last 20 years (from January 1, 1990 to December 31, 2009).Results: Out of the 1927 cases of blindness, 1000 were unilateral, corresponding to a hospital prevalence of 1.84% and 927 cases were bilateral, corresponding to a hospital prevalence of 1.71%. No statistically significant difference was noted between the two (P = 0.14). The leading causes of bilateral blindness were cataract (50.1%), glaucoma (19.7%), and diabetic retinopathy (7.8%) while the leading causes of unilateral blindness were cataract (40.4%), glaucoma (14.1%), and retinal detachment (9.1%). Cataract (51.2%), cortical blindness (16.3%), and congenital glaucoma (10%) were the leading causes of bilateral blindness in children aged less than 10 years.Conclusion: Blindness remains a public health problem in the Douala region with a hospital prevalence which is relatively higher than the national estimate given by the National Blindness Control Program.Keywords: bilateral blindness, unilateral blindness, prevalence, Douala, Cameroon
MODIFICATION OF THE CASAGRANDE'S EQUATION OF PHREATIC LINE  [PDF]
A.K. SHRIVASTAVA, ANURAG JAIN, DEEPALI KANSAL, SHASHANK GUPTA
International Journal of Civil Engineering & Technology (IJCIET) , 2016,
Abstract: The purpose of the present paper is to carry out the seepage analysis for a model to derive the equation of the phreatic line experimentally and thereafter proposing the best solution to trace the line. Sandy silt is used as a base material for this case. Phreatic Line for the model is plotted by carrying out 3 iterations each for two cases, that is, earthen dam without filter and with filter. Their corresponding phreatic line curves are traced on the butter paper on one of the longer side of the model. Plastic channel sections are used to contain the model sealing it air tight with the use of mseal and rubber stoppers. Further, the traced curves are compared with the Analytical solution of Casagrande[2]. Thereafter, a detailed analysis that is using regression modeling, a more accurate solution to obtain an equation of phreatic line in case of sandy silt earthen dam is proposed. The equation can be used for both the cases to determine the phreatic line more accurately than suggested by Casagrande.
Models for calculating phreatic water evaporation on bare and Tamarix-vegetated lands
Shunjun Hu,Changyan Tian,Yudong Song,Xiaobing Chen,Yuetan Li
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-8206-z
Abstract: Groundwater is the main source of water consumption of natural vegetation in arid regions. It is an effective approach to study ecological water demand of natural vegetation by phreatic evaporation. In order to study the ecological water demand of Tarim river basin, based on the observation data of phreatic evaporation on bare lands at the Aksu Water Balance Experimental station from 1989 to 1996, by analyzing the relationship of phreatic evaporation, depth of phreatic surface and evaporation of water, taking the limit rate of phreatic evaporation as the control condition, and based on the objective law that the relation between phreatic evaporation and evaporation of water is nonlinear, we establish models for calculating phreatic evaporation on bare land, which can fully reflect the law of phreatic evaporation in the Tarim river basin. According to the data of depth of phreatic surface and soil moisture when pheratic level decline is caused just by evapotranspiration on Tamarix-vegetated land from 2003 to 2004, we calculate the amount of phreatic evapora-tion and set up models for calculating phreatic evaporation on Tamarix-vegetated land. Phreatic evaporation on bare land and Tamarix-vegetated land could be transformed each other by a Tamarix vegetation conversion coefficient. The test results show that the calculation accuracy of the models is high and the models are suitable for Tarim river basin.
Electrical and Geological Investigations to Conduct Petrophysical Study in Douala-Cameroon Sedimentary Basin  [PDF]
Philippe Njandjock Nouck, Dieudonné Miyem, Aristide Binyam-bi-Mpeck, Quentin Yene Atangana, Simon Ngos
Open Journal of Geology (OJG) , 2013, DOI: 10.4236/ojg.2013.34031
Abstract:

Electrical and geological methods are used to conduct petrophysical study in Douala-Cameroon sedimentary basin along Yaounde-Douala National road No. 3. Studies in this region are made of three outcrops, namely: Missolè II located on the sedimentary basin of Douala, Edea and Sikoum which are outcrops of basement rocks that form the eastern boundary of the sedimentary basin of Douala. This study reveals that the rocks of the sedimentary basin of Douala are mainly composed of sandstone and clay. Both basement rocks of Edea and Sikoum are subjected to the same phases of deformation. These phases of deformation give the quartzite a particular structure that greatly influences the resistivity and density of these rocks and give it a planar anisotropy.

Development Polarisation in Limbe and Kribi (Littoral Cameroon): Growth Challenges, Lessons from Douala and Options  [PDF]
Ojuku Tiafack, Ngouanet Chrétien, Ngwa Nebasina Emmanuel
Current Urban Studies (CUS) , 2014, DOI: 10.4236/cus.2014.24034
Abstract: Limbe and Kribi respectfully in the Southwest and South Regions of Cameroon have been at the centre of Cameroon’s industrial development since the beginning of the 21st Century. These cities are being called upon to play important economic roles through heavy capital investments in the creation of deep sea ports, fishing, mining and energy production industries, the Chad-Cameroon pipeline terminus in Kribi, the cement factory and the petroleum refinery in Limbe amongst others. These developments are attracting and will continue to pull huge population numbers in these cities for jobs leading to urban growth. It is feared that if appropriate measures are not put in place, these emerging industrial towns located along the coastline of Cameroon will face problems of urban growth that are typical of Douala—the pioneer industrial capital of Cameroon and major nerve centre of the Central African sub Region. The growth challenges that Kribi and Limbe will face as well as lessons to learn from the experiences of Douala constitute the first focal point of this paper. These challenges are enormous and include pollution, crime and urban disorder resulting from uncoordinated transport, haphazard construction of habitats and risk vulnerability that threatens the sustainability of these cities. Decision makers in several Sub Saharan African countries are eager to develop their cities but do fail at the onset to project emerging problems that could stiffen this development process in the long run. Consequently, high cost intervention to combat urban disorder becomes the last option and therapy, when it is too late. The diverse measures put in place to redress the problems created are not only costly to the stakeholders (government, benevolent NGOs and the victims) but are indicators of development failures. This of recent has been typical of Yaounde and Douala, the political and economic capitals, respectively, of the Republic of Cameroon. The second important focal point of this paper examines the possible adverse effects of development polarisation in Limbe and Kribi and how the Douala scenario can be averted.
Financial Stock Market and Economic Growth in Developing Countries: The Case of Douala Stock Exchange in Cameroon
Boubakari Ake,Rachelle Wouono Ognaligui
International Journal of Business and Management , 2010, DOI: 10.5539/ijbm.v5n5p82
Abstract: In this article Sims’ causality test based on Granger definition of causality was used to examine causality relationships between stock markets and economic growth in Cameroon based on the time series data from 2006 to 2010. Our findings suggest that the Douala Stock Exchange still doesn’t affect Cameroonian economic growth. Research has been made in this topic and found positive relationship between financial stock market development and economic growth, but in Cameroon the purpose of the government to develop economy, by creating the Douala Stock Exchange is still not reached. After running variance decomposition test of Cholesky, we found systematic evidence that the market capitalization affects positively the GDP. Our paper comes up with the opportunity given to the Cameroonian government to understand that it is time to find financial policies, to encourage companies and develop financial stock market culture, and enhance to push companies to initiate IPO instead of bank loans when money is needed to increase their investment.
Pediatric Traumatic Brain Injury Pattern at the General Hospital, Douala, Cameroon  [PDF]
Aurélien Ndoumbe, Mathieu Motah, Angéline Rolande Assomo Dah, Mireille Moumi
Open Journal of Modern Neurosurgery (OJMN) , 2019, DOI: 10.4236/ojmn.2019.91007
Abstract: Traumatic brain injury is the most common injury during childhood comprising 60% to 90% injuries in children. Pediatric traumatic brain injury has peculiarities as compared to adults, such as less severe injuries and better prognosis. The purpose of this work was to study the pattern of pediatric traumatic brain injury at the General Hospital, Douala, Cameroon. This was a retrospective cross-sectional study, from January 1st, 2008 to December 31st, 2017. Included were all complete medical records of children aged 0 to 15 years old treated for traumatic brain injury, and excluded records of obstetric trauma. Data analysis was done by SPSS software version 18.0. One hundred and three cases of pediatric head injuries were recorded during the study period (frequency 10.43%). The mean age was 7.42 ± 5.028 years, and the sex ratio was 2.67 in favor of boys. Road traffic accidents were the most common etiology (44.7%). 83.5% of the patients were transferred to the emergency department of the Douala General Hospital in second intention and by non-medical transport. The traumatic brain injury was mild in 61.20%. The brain computed tomography scan was performed in 99% of the cases and the most observed lesion was cerebral edema (32.74%). Twenty-eight patients underwent surgical operation. 90.28% of patients have recovered fully, and the global mortality was 3.88%. The prevalence of pediatric traumatic brain injuries at the General Hospital, Douala during the last ten years was 10.43%. Most of the patients recovered fully and the mortality was low.
Indications and the Outcome of the Mammography at Douala General Hospital (Cameroon)  [PDF]
Mathurin Neossi Guena, Natacha Doudou Ra?ssa, Emmanuela Manka’a Wankie, Frantz Cedric Nyatte, Celestine Nguemgne, Wanko Woguep Laure Vanina, Joseph Fotsin Gonsu
Open Journal of Radiology (OJRad) , 2018, DOI: 10.4236/ojrad.2018.82012
Abstract: Background: Recent reports indicate that the use of mammography in breast screening plays a major role in reducing breast cancer-related deaths. It helps to improve quality of care and patient information. However, in Cameroon, there are no organized general breast screening programs which give women the opportunity to regularly screen their breasts, except for the few who take their own initiative for breast screening. Purpose: This study aimed to list indications and results of mammography and/or breast ultrasounds at Douala General Hospital in order to determine the proportion of routine mammographic screening. Method: This descriptive cross-sectional study was carried out at Douala General Hospital using pre-established data sheets. The study recruited all patients who met the selection criteria and reported to the radiology and medical imaging department for breast screening using physical examinations, mammography and/or ultrasounds. Results: The study recruited 372 patients, 96.8% of whom were between 40 to 50 years old. The reasons given for the medical consultation were systematic screening (33.01%); pain (27.18%) and lumps (25.24%). Breast examination by inspection was normal in 87.1% of women, and by palpation in 66.7%. Mammography revealed nodular opacities (18.3%), spiculated images (4.3%) and micro calcifications (3.2%), while ultrasound identified fibroadenomas (16.48%) and cysts (6.18%). Suspicious lesions (ACR 4 and 5) were discovered in 7.6% of cases by mammography and 8.51% of cases by ultrasound. The results indicated that there was no significant association between the use of clinical examination and mammography (p = 0.754). The use of clinical examination alone for breast screening may not be sufficient. Conclusion: Our findings indicate that in Cemaroon, the routine screening mammography accounts for less than one-third (33.1%) of all indications. Benign lesions were most common, however 7.6% and 8.51% of suspicious malignant lesions were observed using mammography and ultrasound respectively.
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