Clinical and Bacteriological Profile of Infections in Sickle Cell Children in Two Referral Hospitals in Niamey, Niger

Introduction: Infections are significant causes of mortality in sickle cell children in resource-limited countries. This study aimed to determine the clinical profile and bacterial ecology of infections in children with sickle-cell disease in two referral hospitals in Niamey. Patients and methods: A retrospective descriptive study was conducted from January 2018 to July 2020 in two referral hospitals in Niamey. All children aged one (1) to 15 years with sickle cell disease admitted for suspected infection, including at least one bacterial culture, were studied. Bacteriological analysis was performed using the appropriate culture media, using BactAlert (Reference 4700003 BTA3D60 BioMérieux). Results: Over 36-months, 350 children with a mean age of 10.9 months were admitted. The sex ratio was 1.2. The SS electrophoretic profile was the most common (93.4%). Immunization status was up to date in 66% of patients. Fever was the common reason for consultation (55.1%). Infection was confirmed in 62 patients (17.7%). The primary diagnoses were bacterial gastroenteritis (24.2%) and urinary tract infection (19.4%). Blood cultures were isolated from Salmonella typhi (13.0%) and Escherichia coli (8.7%). Klebsiella spp (7.1%) and Escherichia coli (5.0%) were detected in cytobacteriological examination of urine. Salmonella typhi (23.5%) and Escherichia coli (5.9%) were isolated on coproculture. Conclusion: Bacterial ecology appears not different from that usually observed in sickle-cell children. Salmonella and Escherichia coli were predominant.

Enzymatic Characterization of Pectinex XXL,a Pectinase Produced by Aspergillus niger,and Its Application in Fruit Juice Production

Pectinex XXL,a commercially prepared pectinase,was investigated for its potential application in the fruit juice industry.Polygalacturonic acid was used as the substrate for determining the enzymatic properties of Pectinex XXL using the DNS method.According to the results,the optimal pH for Pectinex XXL activity was 4.5,and the enzyme was stable in the pH range of 3.0~4.5.The optimal pH and pH stability range are consistent with those of some tropical and subtropical fruits.The optimal temperature for Pectinex XXL activity was 60℃,and the enzyme remained stable after one hour in a water bath set at 40℃.Additionally,the enzymatic activity was not inhibited in the presence of 1 mmol/L of Na^(+),Mg^(2+),Ba^(2+),Co^(2+),Zn^(2+),and Fe^(2+),whereas it was slightly inhibited in the presence of 2 mmol/L of K^(+)and Fe^(2+)and partially inhibited in the presence of 1 and 2 mmol/L of Ca^(2+)and Mn^(2+),demonstrating its good stability in acids and excellent thermal catalytic performance.Based on the above experimental results,depectinization experiments were performed on plantain and cherry tomato juices using different amounts of Pectinex XXL.After one hour reaction with 16 U/mL of the enzyme,the yields of the plantain and cherry tomato juices were substantially increased by 119.03%and 15.97%,respectively,while their light transmittance was remarkably enhanced by 37.65%and 12.35%,respectively.Furthermore,the enzyme reduced the viscosity of the plantain and cherry tomato juices by 88.29%and 29.50%,respectively.The juice production experiments confirmed that this enzyme can significantly improve the yield and light transmittance of plantain juice,while effectively reducing its viscosity.These findings indicate the potential of Pectinex XXL in the industrial production of plantain juice.

Evaluation of formation susceptibility and sand production potential in an offshore field,Niger Delta Basin,Nigeria

Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil facilities.The vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta Basin.The foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(GR),density(RHOB),compressional slowness(DTC),and shear slowness(DTS)logs.Within the Areo oil field,two wells(well 001 and well 002)were correlated.The evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale units.High compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high moduli.The maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the shale.It means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the formations.The Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi respectively.However,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce sand.These findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored into process optimization and cost reduction plans.

Modeling the Spatio-Temporal Dynamics of Local Context for a Contextualized Diffusion of Agroecological Intensification Options in Niger

Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view to sustainable development. The territorial scale of municipalities is not sufficient for this necessary contextualization;the scale of the “village terroir” seems to be a better option. This is the hypothesis we put forward in the framework of the Global Collaboration for Resilient Food Systems program (CRFS), i.e. local context is spatially defined by village terroir. The study is based on data collected through participatory mapping and surveys in “village terroirs” in three regions of Niger (Maradi, Dosso and Tillabéri). Then the links between farm managers and their cultivated land, as well as the spatio-temporal dynamics of local context are analyzed. This study provides evidence of the existence and functional usefulness of the village terroir for farmers, their land management and their activities. It demonstrates the usefulness of contextualizing agricultural options at this scale. Their analysis elucidates the links between “terroirs village” and the specific functioning of the agrosocio-ecosystems acting on each of them, thus laying the systemic and geographical foundations for a model of the spatio- temporal dynamics of “village terroirs”. This initial work has opened up new perspectives in modeling and sustainable development.

Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet

BACKGROUND The gluten-free diet(GFD)has limitations,and there is intense research in the development of adjuvant therapies.AIM To examine the effects of orally administered Aspergillus niger prolyl endopeptidase protease(AN-PEP)on inadvertent gluten exposure and symptom prevention in adult celiac disease(CeD)patients following their usual GFD.METHODS This was an exploratory,double-blind,randomized,placebo-controlled trial that enrolled CeD patients on a long-term GFD.After a 4-wk run-in period,patients were randomized to 4 wk of two AN-PEP capsules(GliadinX;AVI Research,LLC,United States)at each of three meals per day or placebo.Outcome endpoints were:(1)Average weekly stool gluten immunogenic peptides(GIP)between the run-in and end of treatments and between AN-PEP and placebo;(2)celiac symptom index(CSI);(3)CeD-specific serology;and(4)quality of life.Stool samples were collected for GIP testing by ELISA every Tuesday and Friday during run-ins and treatments.RESULTS Forty patients were randomized for the intention-to-treat analysis,and three were excluded from the per-protocol assessment.Overall,628/640(98.1%)stool samples were collected.GIP was undetectable(<0.08μg/g)in 65.6%of samples,and no differences between treatment arms were detected.Only 0.5%of samples had GIP concentrations sufficiently high(>0.32μg/g)to potentially cause mucosal damage.Median GIP concentration in the AN-PEP arm was 44.7%lower than in the run-in period.One-third of patients exhibiting GIP>0.08μg/g during run-in had lower or undetectable GIP after AN-PEP treatment.Compared with the run-in period,the proportion of symptomatic patients(CSI>38)in the AN-PEP arm was significantly lower(P<0.03).AN-PEP did not result in changes in specific serologies.CONCLUSION This exploratory study conducted in a real-life setting revealed high adherence to the GFD.The AN-PEP treatment did not significantly reduce the overall GIP stool concentration.However,given the observation of a significantly lower prevalence of patients with severe symptoms in the AN-PEP arm,further clinical research is warranted.

Primary Non-Hodgkin’s Malignant Lymphoma of the Uterus at the Reference Hospital of Maradi/Niger: A Case Report

Malignant non-Hodgkins lymphoma (MHNL) of the uterus is uncommon. We report a case diagnosed on the basis of histologic and immunohistochemical studies of a hysterectomy specimen induced by a very painful pelvic mass in a 50-year-old patient with no previous history of the disease. It was classified as Ann Arbor IV Bb after imaging, given the medullary infiltration and signs of clinical and biological evolutivity: the patient had received two courses of chemotherapy, CHOP protocol. She died 23 days after the second treatment due to a hypertensive crisis.

Reform of the Irrigation Sector and Creation of Functional and Sustainable Irrigation Water Users Associations (AUEI) in Niger: Capitalization of the Experience of the Konni AHA

During the 1980s, as part of a policy of liberalization, following budgetary cuts linked to the implementation of structural adjustment programs, management responsibilities for AHAs were transferred from ONAHA to cooperatives concerned. Due to lack of financial resources, but also because of poor management, everywhere in Niger we are witnessing an accelerated deterioration of the irrigation infrastructure of hydro-agricultural developments. Institutional studies carried out on this situation led the State of Niger to initiate a reform of the governance of hydro-agricultural developments, by streng-thening the status of ONAHA, by creating an Association of Irrigation Water Users (AUEI) and by restructuring the old cooperatives. Indeed, this research aims to analyze the creation of functional and sustainable Irrigation Water User Associations (AUEI) in Niger in a context of reform of the irrigation sector, and based on the experience of the Konni AHA. It is based on a methodological approach which takes into account documentary research and the collection of data from 115 farmers, selected by reasoned choice and directly concerned by the management of the irrigated area. The data collected was analyzed and the results were analyzed using the systemic approach and the diagnostic process. The results show that the main mission of the AUEI is to ensure better management of water, hydraulic equipment and infrastructure on the hydro-agricultural developments of Konni. The creation of the Konni AUEI was possible thanks to massive support from the populations and authorities in the implementation process. After its establishment, the AUEI experienced a certain lethargy for some time due to the rehabilitation work of the AHA but currently it is functional and operational in terms of associative life and governance. Thus, the constraints linked to the legal system, the delay in the completion of the work, the uncertainties of access to irrigation water but also the problems linked to the change in mentality of certain ONAHA agents constitute the challenges that must be resolved in the short term for the operationalization of the Konni AUEI.

Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin

The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challenge.In the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the field.Within the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).In terms of bathymetry,it is noted that irrespective of systems tracts,the RSP Index(RI)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf areas.Amongst all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest RSP.Sand development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation rates.This is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand deposition.On the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine shales.Interpreted seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the field.The initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea level.This approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volume estimation.

Cotton Leafhoppers, Amrasca biguttula (Ishida, 1913) (Hemiptera: Cicadellidae), Identified as a New Species on Okra and Guinea Sorrel in Niger

Leafhoppers (jassids) are well-known pests of vegetable crops in Niger. They are often part of a parasitic complex that causes varying degrees of damage. Over the last two crop years, the Niamey region has seen a heavy outbreak of leaf hoppers on okra and guinea sorrel. These insects alone have caused spectacular damage, resulting in losses ranging from 50% to 100% of unharvested plants. Following this observation, infested fields were surveyed, specimens sampled, and the responsible species identified. Two sites were surveyed in the city of Niamey. At each site, two plots of okra and two of guinea sorrel were visited. Fifty (50) plants were randomly sampled using the double “W” method per plot. The sampled plants were used for active and passive leaf hopper capture, damage description and loss assessment. Captured leaf hoppers were identified based on their morphology observed with a binocular magnifying glass and compared with the data in the identification keys. The symptoms observed in the plots were yellowing, leaf curling and drying, stunting, abortion of flowers and immature fruit and very low production. Identification results revealed the single species Amrasca biguttula (Ishida, 1913), which can be considered a new invasive species in Niger. Further confirmation of this identification by molecular tests, the distribution of the pest in Niger and the development of appropriate control methods would yield good prospects.

Characteristics of Gold and Its Mineralization Style in the Boulon Djounga Eastern Perimeter of Liptako Mining Company (Central Southwestern Niger)

The Boulon Djounga eastern perimeter is part of the Tiawa operating permit of the Société des Mines du Liptako (SML), located in the central southwestern part of Liptako (Niger). In this study, we used field data, Reverse Circulation (RC) surveys and chemical analyzes of gold to determine the characteristics of gold and its mineralization style. The eastern perimeter of Boulon Djounga is represented by a succession of metabasalts and metasediments both intersected by intrusions of quartz and dolerite dykes, and covered by sandstone and clayey rocks. Gold is present in low contents (0.00 - 0.30 ppm) in the sedimentary cover and in medium (0.30 - 1.00 ppm) or high contents (1.00 - 4.534 ppm) in the metasediments, and in the gray quartz veins and locally in the volcanics. It exists in a disseminated state or in a concentrated state in the surrounding areas in the form of discrete grains associated with sulphurous minerals (pyrite: FeS2, chalcopyrite: CuFeS2 or arsenopyrite: FeAsS). The presence of gold in the quartz veins, and the NE-SW and NW-SE orientations of the ore bodies suggest that the eastern Boulon Djounga gold mineralization would be established during a late magmatic extensive phase.

New understanding and exploration direction of hydrocarbon accumulation in Termit Basin, Niger

Based on the seismic and drilling data, casting thin sections, geochemical analysis of oil and rock samples, and hydrocarbon generation history simulation, the hydrocarbon accumulation characteristics and exploration direction of Termit superimposed marine–continental rift basin are discussed. The Termit basin is superimposed with two-phase rifts(Early Cretaceous and Paleogene). The subsidence curves from two wells on the Trakes slope in the east of the basin show high subsidence rate in the Late Cretaceous, which is believed to be high deposition rate influenced by transgression. However, a weak rift may also be developed. The depositional sequences in the Termit basin were controlled by the Late Cretaceous marine transgression cycle and the Paleogene lacustrine transgression cycle, giving rise to two types of superimposed marine–continental “source-sink” deposits. The marine and continental mixed source rocks developed universally in the whole basinduring the marine transgression period, and are overlaid by the Paleogene Sokor 1 reservoir rocks and Sokor 2 caprocks developed during the lacustrine transgression period, forming the unique superimposed marine–continental basin in WCARS. The early low geothermal gradient in the Termit basin resulted in the late hydrocarbon generated by the source rock of Upper Cretaceous Yogou in Paleogene. Mature source rock of Upper Cretaceous Donga developed in the Trakes slope, so that the double-source-supply hydrocarbon and accumulation models are proposed for the Trakes slope in which formed the oil fields. Due to virtue of the newly proposed hydrocarbon accumulation model and the exploration activities in recent years in the Termit superimposed marine–continental rift basin, an additional effective exploration area of about 2500 km2has been confirmed in the east of the basin. It is believed that potential domains such as Sokor 1, Donga and Upper Cretaceous lithologic traps in the southeast of the basin are key expected targets for exploration and frontier evaluation in future.

Inventory of Host Plants and Parasitoids of the Fall Armyworm (FAW), Spodoptera frugiperda (JE Smith), in the Southern Agricultural Zone of Niger

The fall armyworm, Spodoptera frugiperda (JE Smith), is a polyphagous pest reported in sub-Saharan Africa since 2016 and has expanded rapidly in almost Africa. In Niger, Spodoptera frugiperda (JE Smith) is considered like a major pest of maize, to which it causes significant damage, in a context where proven control methods against this moth remain almost non-existent. The objective of the present study was to determine the economic importance of FAW through the damage caused to the different host plants and to identify the parasitoids of this caterpillar. The study was conducted in the southern agricultural zone of Niger, specifically in the regions of Dosso, Maradi, Tahoua and Zinder. FAW eggs and caterpillars were collected from six villages in each region and then incubated and reared in the entomology laboratory of INRAN in Maradi. The rate of infestation of the different crops by FAW was determined as well as the observation of the beneficiaries. The results obtained indicate the presence of FAW on millet with an attack rate varying from 45.7% to 68%, sorghum with 47.2% to 62.25% and sesame with 9.7%. This work also revealed an oophagous parasitoid, Telenomus remus with 138 ± 23 and larval parasitoids, Cotesia sp with 16 ± 1 maximum number of individuals emerged from the collected material. Also, it was identified the parasitoid Cotesia icipe with a rate of parasitism from 4.6% to 5.75%;the Charops ater whose rate of parasitism varies from 4.5% and 12.25% but for Chelonus insularis with 17.25% and Tachnidae with 53%. These very interesting results will constitute a basis for the development of biological control and a component of an agroecological management strategy of caterpillar.

Application of Spatial Techniques for the Identification of Discontinuous Aquifers of the Basement in Semi-Arid Environment: A Case of Bagzan Mount Plateau, Aïr Massif (North, Niger)

Bagzan mount is located in the Aïr massifs region. This locality, which is constituted only by the granites and volcanic formations, knows the difficulty of water supply that depends on rainfall. This present study has the objective of fracture mapping that allowed to the fractured aquifer in Bagzan mount. The methodological approach used has a treatment of Digital Elevation Model (DEM imagery), hydrogeological and geological approach in the field. This process allowed us to map the lineaments and elaborate a fracturing map after the validation stage. The fracturing map showed that the fractures network is distributed in the N70°-N80°, N60°-N70°, N50°-N60°, and two secondary directions N90°-N100° and N120°-N140°. These fracturing maps allowed us to have precious information in groundwater research in Bagzan mount, due to their geological and hydrogeological complexity.

Antibiotic Resistance in the Uropathogenic Enterobacteria Isolated from Patients Attending General Reference Hospital (GRH) of Niamey, Niger

Background: Urinary tract infections (UTIs) are a frequent reason for consultation and lead to a significant and sometimes inappropriate prescription of antibiotics. The latter favors antibiotic resistance and an increase in mortality as well as the cost of treatment. The present study aims to contribute to the fight against antibiotic resistance of enterobacteria. Methods: This is a prospective study from January to December, 2021 in the Microbiology laboratory of the General Reference Hospital (GRH) of Niamey including 3369 urine samples. The antibiotic resistance of enterobacteria was determined using the Viteck-2 method. Results: At least 280 strains of Enterobacteriaceae were isolated from the patient’s urine. Among these strains, Escherichia coli was the most predominant (74.64%), followed by Klebsiella pneumoniae (16.07%) and Enterobacter cloacae (7.14%) and other enterobacteria 2.15%. These Enterobacteriaceae are more common in community patients than in hospitalized patients. The average age of patients is 52 years and the age group most affected by these enterobacteria is 46 - 60 years (23.33%). The female sex is the most affected sex with (51.07%) against (48.97%) for the male sex with 1.04 as sex ratio. The hospitalization departments most affected by these enterobacteria are Nephrology (29.23%) and Endocrinology (21.54%). Up to 75% of the Enterobacteriaceae isolates show high resistance to ampicillin, amoxicillin-clavulanic acid, ticarcillin, piperacillin-tazobactam, cefoxitin, cefixime, ceftazidime, ceftriaxone, cotrimoxazole, nalidixic acid and ofloxacin. Conclusion: The high rate of antibiotic resistance among enterobacteria in urine is of concern. Only a few Enterobacteriaceae show low resistance to ertapenem, imipenem, amikacin, gentamicin, fosfomycin and nitrofurantoin. Therefore, these antibiotics are recommended as first line treatment for urinary tract infections.

Challenges of Groundwater Development and Supply in the Niger Delta, Nigeria

Some problems of groundwater development in the Niger Delta ranging from negligence to geological peculiarities are examined to highlight the importance and application of geologic knowledge and research for decision making and averting failure in groundwater development for provisional use. Although the geology and hydrogeologic properties of the aquifer system in the Niger Delta immensely favors groundwater development, there are several recorded cases of failed groundwater development projects poor water quality, dry boreholes and boreholes with surprisingly low yield which could have been avoided. This is due to the perception that since groundwater is prolific, geologic and locational peculiarities can be ignored. This research has highlighted the importance of the knowledge of the hydrogeology of the different geologic units as significant factor in the success of groundwater projects through the correlation of past research of geologic units and groundwater potentials, quality and challenges with the present projects implemented in some of the locations. Cases where groundwater projects are executed with wrong exploration options and without consideration of the peculiarity of the geologic units of the project area, including engagement of incompetent contractors, and negligence to the existing regulatory framework for groundwater development in Nigeria are presented. In order to promote sustainable groundwater development and management in the Niger Delta, this research highlights and recommends the pragmatic use of geologic information including various technical, institutional, regulatory and management measures which have the capacity to avert challenges in groundwater development for provisional use.

Factors Associated with Non-Adherence to Treatment in Sickle Cell Patients Monitored at the National Reference Center for Sickle Cell Disease in Niger

Introduction: Sickle cell disease is a real public health problem in the world and particularly in Niger where the prevalence of the S gene is estimated at 25% and that of the homozygous forms at between 1% and 2%. Treatment combines quarterly follow-up of patients and management of complications. The objective of this study was to identify the potential explanatory factors of non-adherence to treatment in sickle cell patients followed at the national reference center for sickle cell disease in Niger. Methods: This is a cross-sectional study of sickle cell cases followed at the CNRD in Niger. The population consisted of all sickle cell patients followed in this center in 2021. The data collection techniques were individual interviews and documentary reviews. Non-adherence was assessed with the Girerd test. Descriptive statistical tests and simple and multiple logistic regression models were performed. Results: A total of 368 patients were enrolled. The median age is 7 years (4;10) and the sex ratio is 1.04. Ninety-eight (98) or 26.6% were compliant and 270 (73.4%) were non-compliant. In multivariate analysis, the factors independently and negatively associated with non-adherence to treatment were schooling (adjusted OR [95% CI], p-value), 0.17 [0.10 - 0.30];p Conclusion: The factors influencing treatment compliance identified in this study are all modifiable. To prevent the complications of sickle cell disease, we must fight against ignorance, make care services accessible and make care free.

Neonatal Seizures: Epidemiological, Diagnostic Aspects and Short-Term Outcome at Issaka Gazoby Maternity Hospital of Niamey, Niger

Introduction: Neonatal seizures are one of the most challenging situations for paediatricians. The objective of this work was to study the epidemiological and diagnostic aspects and short-term outcomes of neonatal seizures at Issaka Gazoby Maternity Hospital in Niamey. Patients and Methods: This was a prospective study from November 2020 to April 2021 in the neonatology department of Issaka Gazoby Maternity Hospital. All newborns aged 0 to 28 days hospitalized for seizures and/or having convulsions during hospitalization were included. Neonatal characteristics, diagnostic aspects, and their outcomes were studied. Data were analyzed using SPSS version 20 software. Results: Of the 3.068 newborns admitted, 69 cases of neonatal seizures were recorded (2.24%). The sex ratio was 1.22, and 94.2% of neonates were born at term. Generalized crises were found in 50.7%. The main etiologies were perinatal asphyxia (46.4%) and early-onset neonatal infection (40.6%). The death rate was 20.3%. Neonates died between one (1) and three (3) days of age in 42.9%. The main death causes were perinatal asphyxia (50%) and early-onset neonatal infection (21.4%). Conclusion: Neonatal seizures are uncommon frequent, with a semiology dominated by generalized seizures. Mortality is high. The reinforcement of preventive measures is necessary.

Impact of Dredging on Coastal Infrastructure: Case Studies from Okrika and Port Harcourt, Niger Delta

Sand excavations in river beds have compromised the safety of several bridges in recent years. Large scale sand mining from river beds is now common in the Niger Delta, due to the necessity of reclaiming land for development purposes and to meet construction needs in the region. There is currently no regulation as to where sand can be mined in river channels because of the lack of adequate understanding of the risks to coastal infrastructure involved with its abstraction. The phenomenon of bridge Abutment and bank failure induced by excessive dredging of sand river bed is considered. Two types of instability were distinguished, one relating to the equilibrium slope of the riverbed and the other riverbank instability. An empirical relationship in the form Xs = 3Htan(90 - α) has been developed through analysis, supported by examples that a minimum distance of 94 m (for sand river beds) from a bridge should be observed for sand abstraction in order to guaranty the safety of bridge foundation. For clay riverbeds, slightly shorter minimum distances can be considered safe. The study further shows that the capacity of sand borrowing in river channels to generate bank instability is dependent on the composition and stratigraphy beneath the river bed.

Farmer Participatory Evaluation of Sorghum Hybrid in Niger

Participatory varietal selection (PVS) with farmers and Seed Companies was conducted at Maradi research station (07°05'E/13°48'N) and in farmer field to evaluate and select sorghum hybrid varieties for high yield and other important agronomic traits. The experimental design was a randomized complete block with three replications where flowering (days), plant height (cm) and yield (kg) were collected. The analysis of variance showed highly significance among treatments of all traits measured Environment and Genotype by Environment interactions also contributed significantly to the performance of yield components. The highest average grain yield was recorded from hybrids P9511A x ST9007-5-2-1 (4289 kg/ha), NE223A x 90SN1 (3666 kg/ha), NE223A x Sepon 82 (3533 kg/ha) and NE223A x P9405 (3519 kg/ha) across locations. Farmers’ preferences were the panicle size, good seed set, earliness, and seed color. Hence, in a variety selection farmer’s preferences focus more on prioritized yield-related trait. The best varieties ranked by traits of interest were P9511A x ST9007-5-2-1, NE223A x 90SN1, NE223A x P9405 and P9511A x SEPON 82 that performed well under their circumstances. The results showed that farmers’ preferred varieties match with researchers. Therefore, based on objectively measured traits, farmers’ preferences and the agro ecologies of the site, varieties NE223A x 90SN1 and P9511A x ST9007-5-2-1 were found promising for production.

Application of a Multi-Criteria Approach for the Assessment of Groundwater Potential in the Basement Zone: A Case of Tamou (South West Niger)

The commune of Tamou, located in the Department of Say in Niger, occupies the southwestern part of the Liptako crystallophyllian basement domain. In this area, the problem of the drinking water supply of the populations is acute, because of the low flow rates of the drillings capturing the crystallophyllian formations and the Voltaian sandstones, the failure rates of the drillings are very high there. Therefore, the main objective of this study is to improve the knowledge of the areas potentially favorable for the implantation of drillings likely to give more satisfactory flow rates. The methodological approach, based on the collection of data (Landsat 7 ETM+ satellite imagery, borehole data, geological and topographical maps) and their processing by a combination of remote sensing and GIS tools and a field check, allowed the elaboration of maps of availability, accessibility and exploitability of the groundwater resources in the study area. The maps developed were analyzed with a Spatial Reference Hydrogeological Information System following the technique of aggregation by weighting to generate the map of productive drilling sites. The results show that the area is moderately rich in groundwater (58%) and that only 31% of the potential is exploitable. The groundwater potential map shows that 46% of the study area is suitable for drilling.