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Climate change symposium sur de changement climatique 2011
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Community based participatory epizootiology of livestock kept by Awotan Women, Ido LGA, Oyo State, Nigeria
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Page will reload when a filter is selected or excluded.- Niger Delta Development Commission 2 results 2
- Odi 2 results 2
- Peace and conflict impact assessment 2 results 2
- intervention programme 2 results 2
- A nationwide equine influenza virus surveillance was carried out between January 1989 and January 1995 during which nasopharyngeal swabs, tracheal washes and respiratory tract tissue homogenates were obtained from symptomatic and asymptomatic equine species in various parts of Nigeria for virus isolation and characterisation. Three equine influenza viruses were independently isolated in 10-11 day old embryonated hen eggs and Madin Darby canine kidney monolayer cells with TPCK-trypsin incorporated into the culture medium. The virus isolates were characterized antigenically, immunogenically and genetically which made them the first equine influenza viruses isolated and characterized in tropical Africa. Antigenic analyses with mono-specific antisera raised against a number of respiratory disease viruses including Paramyxoviruses, Adenoviruses, Herpes viruses, Alphavirus, Rhinoviruses, Equine arteritis viruses, African horse sickness viruses and Influenza viruses showed that the three virus isolates were influenza A viruses while haemagglutination and neuraminidase inhibition assays using influenza virus specific Mabs and polyclonal antisera showed the three viruses to be antigenically H3N8, members of equine-2 subtype of influenza A viruses. The three isolates were respectively named A/Equine/Ibadan/4/91, A/Equine/Ibadan/6/91 and A/Equine/Ibadan/9/91 in accordance with the recommendations of the World Health Organisation and the International Committee on Virus Taxonomy. Their antigenic cross-reactivity with panels of Mabs and polyclonal antisera indicated that the three viruses were antigenically divergent although they were all H3N8 viruses and were representatives of a homogenous population. They were reactive with Mabs and antisera directed against H3 equine viruses isolated in 1963, 1976, 1979, 1981 and 1986. This broad reactivity suggested that these isolates were similar to but not still different from those isolated in Europe and USA between 1963 and 1987. Virus protein synthesis and cleavability of the HA polypeptide in tissue culture were investigated by pulse-chase experiments. The results showed some heterogeneity in the non-glycosylated polypeptides particularly those of the ribonucleoprotein (RNP) complex while the HA glycoproteins of the three viruses were not cleaved in any of the cell types used in contrast to equine H7 and pathogenic avian H5 and H7 HAs. The molecular weights of the polypeptides were within the range previously determined for influenza A viruses. The heterogeneity of the RNP complex and antigenic divergence of the viruses’ HAs were confirmed by sequence analysis carried out in molecular studies. Virus infectivity was investigated by plaque assay using chicken embryo fibroblast (CEF) monolayer cells and virus titration in embryonated hen eggs. The results showed that the viruses were infectious with plaguing efficiency being comparable to efficiency of virus infectivity in embryonated hen eggs. Infectivity, antigenicity and immunogenicity of the three viruses were confirmed in-vitro using peripheral blood lymphocytes in lymphoproliferation assays and in-vivo in an equine model in which the viruses induced haemagglutination inhibiting and protective neutralising antibodies following experimental infections. The proliferating cells were also characterised and the immunoglobulin isotypes produced were determined. Molecular characterisation and genetic analyses of the three viruses were accomplished to determine the origin of the genes encoding the virus non-glycosylated polypeptides as well as those of the surface HA glycoprotein. Reverse transcription (RT) results showed the eight RNA segments of the three isolates and confirmed them as influenza A virus RNAs. No subgenomic RNAs or defective interfering particles were observed in the RNA transcripts. Nucleotide sequence analyses were carried out using three sequencing strategies of cDNA, vRNA and plasmid DNA sequencing with the dideoxy chain termination procedure. Partial nucleotide sequences were obtained from cDNAs, vRNAs and plasmid DNA clones of RNA segments 1, 2, 3, 5, 7 and 8 with the method of multiplex RT/PCR and cycle sequencing using radiolabelled segment specific oigonucleotides of 18, 24 or 25 mers. Complete nucleotide sequences of segment 4 (HA genes) were also determined on the same PCR products (cDNA) and vRNA using end-labelled oligonucleotides of both plus and minus sense. The partial nucleotide sequence data were analysed using a programme for "best-local-homology- rapid-search" on a digital array processor while the complete HA nucleotide and deduced amino acid sequence analyses were carried out using the University of Wisconsin Genetics Computer Group (GCG) package of programmes. Phytogenetic analysis was done with the distances, neighbour joining and DNAPARS of the PHYLIP package. Analyses of the viruses’ gene sequences confirmed that their genomes were similar to each other and to those of other H3N8 influenza viruses isolated from equines and also revealed the origin, evolution and genetic relatedness of the genes. Comparison of the partial cDNA sequences with virus DNA sequences in the database (EMBL sequence library) showed that for segments 1, 2, 5, and 7, the closest related sequences were from equine H3 viruses isolated in 1986 in USA (Tennesse/5/86 for segments 2, 5 and 7, Kentucky/2/86 for segments 1 and 5. Segment 5 was equally related to both viruses). The nucleotide sequence for segment 3 was most closely related to an equine-1 virus isolated in U.K. in 1973 (London/1416/73, H7N7) probably due to genetic exchange while segment 8 sequence was most closely related to an equine H3N8 virus isolated in U.K. in 1976 (Newmarket/76). The complete nucleotide and deduced amino acid sequences as well as phytogenetic analysis of the HA genes (RNA segment 4) showed a closer relationship albeit with nucleotide and amino acid substitutions between the three Ibadan viruses and those that were isolated in Europe in 1989 and 1991, the prototypic European strain, Suffolk/89 and Arundel/12369/91 isolated in U.K., Taby/91 isolated in Sweden, Hong Kong/92 isolated in the Far East in 1992 and Laplata/1/93 isolated in South America. These findings group the Ibadan viruses with those predominating and contemporarily causing disease in the Western Hemisphere rather than with viruses previously isolated from the north and south of African continent. Variation was observed in the nucleotide sequences of the Ibadan viruses HA genes. Some of the base changes resulted in amino acid changes which mapped to antigenic sites or within signal sequence in the HA1 domain as a result of a process of antigenic or genetic drift. The Ibadan viruses also showed some variation from the prototypic European virus (Suffolk/89) and these base changes also resulted in amino acid changes resulting in antigenic drift. Phytogenetic analysis showed the evolutionary lineages in equine H3 viruses isolated since 1963 along two paths one of which included the Ibadan viruses as well as viruses isolated in Europe between 1989 and 1991 and the Far East in 1992 and S. America in 1993 which form the 1989/93 cluster while the other lineage included viruses isolated in South America in 1987 and 1988 (Brazil/87, Laplata/88) and in the Far East in 1971 (Tokyo/3/71) all of which are very close to the original prototype equine-2 virus (Miami/63). These results demonstrate a faster evolutionary rate for recent equine H3 HA genes away from the original prototype virus. Overall, the results of these studies have (i) confirmed the occurrence of equine-2 H3N8 influenza viruses of distinct lineages in Nigerian equine populations in a tropical environment (ii) indicated antigenic drift among equine H3N8 viruses as earlier reported and confirmed that drift strains can co-circulate in equine populations, (iii) showed the origin, evolution and genetic relatedness of the viruses genes as well as their biological characteristics, (iv) provided the hitherto unavailable information on the status of equine influenza virus in this part of the world and (v) served to re-emphasise the potential of influenza virus for rapid global spread and the need for better control strategies. 1 results 1
- Access control 1 results 1
- Adaptation Strategies 1 results 1
- Aerobic exercise 1 results 1
- Agriculture 1 results 1
- Agro-industrial by-products are being used as an alternative to traditional building materials because the construction of buildings and roads emits greenhouse gases and consumes energy. This study explores pervious concrete (PC) that includes sorghum husk ash (SHA) and palm kernel shell (PKS) as alternatives to cement and natural aggregate (NA) to obtain a robust, sustainable and cost efficient pavement structure. Mixtures of PC were produced with 5–25% SHA at a level of 5% by weight as substitution for cement and 20–100% PKS at a level of 20% by weight as substitution for NA. The performance of SHA-PKS based PC was evaluated using density, compressive strength, porosity and permeability. Sustainability of combining SHA and PKS on PC was also examined by measuring embodied carbon and energy as well as cost efficacy. Thereafter, Artificial Neural Network (ANN) models to optimize the prediction of porosity and permeability were developed for the PC. Utilizing the coefficient of determination (R2), mean square error (MSE), and root mean square error (RMSE), the suitability of the ANN models was assessed. Results showed that as SHA and PKS amounts increased, PC densities declined. Except at 5%, when they were higher than the control, compressive strength decreased as SHA increased. On the other hand, the addition of PKS increased PC porosity and permeability while lowering density and compressive strength. Mixture of SHA-blended PKS based PC with 40% PKS and 20% SHA attained the compressive strength, porosity and permeability values specified for PC which is adequate for sidewalks and cycle ways. This mixture lowers the embodied carbon, embodied energy and cost by 23%, 20% and 24% respectively. The adopted ANN models adequately predicted the porosity and permeability of PC (R2: 0.99; MSE: 0.88–1.76; RMSE: 0.94–1.32). The findings of this work offer a sustainable path to recycle SHA and PKS for constructions. 1 results 1
- Analysis of social support networks of young adults was conducted on the basis of two scales. The Visual Analog Scale (VAS) and the Whom Do You Turn To Scale (WDYTT) among 150 Junior and Senior Civil Servants of the Oyo State secretariat Ibadan. Their mean (X) age was 37.5 while the Standard Deviation (SD) was 15.1. The VAS and WDYTT scale were used to assess the extend of variation in the social network in the adult period of the life cycle. That is, a Visual Analog Scale (VAS) assesses the extent of closeness for seven interpersonal relationships and a second scale determining to whom the respondents would turn to in 14 situations (WDYTT). Chi-Square-test and t-test analyses were employed. The result showed significant differences, between the best female friend mother etc. Family of orientation vs friends as well as intergenerational vs intra generational were also compared on WDYTT scale. Result also showed significant difference on the friends (interpersonal as first and second choice. The implication and recommendation of the study were made on the need for further researches on social network and relationship across the life-span in Nigeria. 1 results 1
- Availability 1 results 1
- Bone setting 1 results 1
- CEA 1 results 1
- Cardiorespiratory function 1 results 1
- Carotenoids 1 results 1
- Climate change 1 results 1
- Climate-variability 1 results 1
- Clinics 1 results 1
- Combining ability 1 results 1
- Common rust 1 results 1
- Community based 1 results 1
- Competition 1 results 1
- Corruption 1 results 1
- Cowpea 1 results 1
- Cycling of nutrient elements by exotic tree species is becoming increasingly important to the sustenance and productivity of rainforest environment. Apart from the provision of shade and fruits to rural farmers, the incorporation of these exotic tree stands into farmland helps to return nutrients to the soil. Despite the importance of exotic trees in the rainforest environment, information on nutrient cycling under individual tree stands in south-south Nigeria has not been adequately documented. In this study, the cycling of nutrients under isolated exotic stands of Terminalia cattapa, Mangifera indica and Persea gratissima in Orogun, Ughelli North Local Government Area, south-south Nigeria, was therefore investigated. Litterfall, rainwash (throughfall and stemflow) and soil samples were collected from 15 stands of each of the three exotic tree species as well as 15 control plots in the rainforest. Litterfall and rainwash were collected daily for a year. Litterfall was collected with 1m² litter traps, throughfall and incident rainfall with funnel-type collectors; and stemflow with ¾ mm hose wound round the tree trunks. Soil samples were collected from 0-15 cm and 15-30 cm depth using core sampler. Nitrogen, phosphorus and potassium content of samples of litter, rainwash and soil, as well as soil organic matter were analysed using standard techniques. Descriptive statistics and ANOVA were used to compare nutrients returned to soil by the isolated trees and the control via litterfall and rainwash; while soil nutrients were correlated with litterfall and rainwash. From the stands of T. cattapa, M. indica, P. gratissima and the control, litter productions were 83.0, 76.5, 60.2 and 77.3 g/m²/yr; annual throughfall volumes (%) were 89.2, 88.6, 91.0 and 84.2; while stemflow volumes (%) were 6.5, 6.2, 7.6 and 7.3 of the incident rainfall (4325mm). The nitrogen returned to the soil via litterfall was 5.7±1.4, 3.4±0.4, 2.4±0.1 and 9.1±1.7 kg/ha/yr respectively for T. cattapa, M. indica, P. gratissima and the control. The corresponding values of phosphorus returned in litterfall were 0.7±0.2, 0.5±0.1, 0.4±0.1 and 0.6±0.1 kg/ha/yr; while for potassium were 4.9±1.3, 2.6±0.2, 2.1±0.4 and 3.4±0.8 kg/ha/yr. The potassium returned via throughfall for the isolated trees and the control were 10.6±5.9, 9.5±5.9, 7.4±4.4 and 8.8±5.7 kg/ha/yr; while the corresponding values of potassium returned via stemflow were 0.7±0.6, 0.3±0.3, 0.4±0.3 and 0.7±0.6 kg/ha/yr respectively. Nitrogen, phosphorus and potassium returned to soil via litterfall, throughfall and stemflow varied significantly (p<0.01) amongst the isolated exotic trees and the control. Litterfall, throughfall and stemflow accounted for 54%, 40% and 6% of the total quantities of nutrients returned to soil respectively. Litter production and soil organic matter correlated positively under T. cattapa (r=0.8), M. indica (r=0.8), P. gratissima (r=0.8) and the control (r=0.9). Soil nitrogen, phosphorus and potassium correlated positively with litterfall (r?0.2), throughfall (r?0.1) and stemflow (r?0.5) respectively. Isolated exotic trees over time returned nutrients to the soil, thereby improving soil nutrient status and sustaining soil productivity in the rainforest environment. 1 results 1
- DLC 1 results 1
- DNA Binding Site 1 results 1
- DNA and oxidative damage 1 results 1
- Development interventions are aimed at promoting positive change, but they can equally have negative impact, especially in conflict-prone contexts. Whereas existing studies on Odi and the Niger Delta at large mainly focused on the history, environ-ment, culture, conflict and security situations, the peace and conflict impact of Nige-rian government‘s socio-economic interventions in the area have not been fully ex-plored. This study, therefore, assessed the Niger Delta Development Commission‘s (NDDC) interventions, to determine their relationship with the Commission‘s man-date, strategies, and community needs; their interactions with the community; and their impact on the dynamics of peace and conflict in Odi, a community that has at-tracted many interventions after the 1999 massacre. The study adopted the grounded theory and case study research designs. Primary and secondary data were collected through key informant and in-depth interviews, official documents and non-participant observation. Fifty-four key informant interviews were conducted with seven members of the Traditional Ruling Council and the Community Development Committee, six religious leaders, five women leaders, five Youth Coun-cil executives, 24 project beneficiaries, 12 NDDC staff, and five NDDC consultants. Forty-seven in-depth interviews were also held with six school teachers, ten politi-cians, and two law enforcement agents in Odi, five international/non-governmental organisations staff, six activists, and eight academics and professionals. The Niger Delta Regional Development Master Plan, the NDDC Act, and website contents were consulted. Non-participant observations were carried out at NDDC project sites in Odi. The data gathered were content analysed. The NDDC integrated development strategy correlated with NDDC‘s mandate and people‘s needs. However, the Commission, in implementing its interventions, contra-vened some of its articulated guiding principles and policies like promoting good gov-ernance, transparency, participatory decision-making, and impact assessment. Also, inadequate community consultation caused dissonance in NDDC‘s and community‘s prioritisation of needs. Moreover, due to inadequate consideration for peace and con-flict sensitivity, the interventions produced series of positive and negative impact on peace and conflict dynamics in Odi. Construction of roads and educational facilities, rural electrification and training in modern agricultural practices impacted positively on the structural causes of conflict. They brought federal government‘s presence to Odi; provided income for male youths employed as labourers and for construction ma-terials‘ suppliers as well as capacity building in modern agricultural practices. How-ever, the community perceived the NDDC interventions as resources and competed for in a socio-political environment characterised by pervasive corruption and bad gov-ernance. This provided sufficient conditions for spirals of negative consequences that ultimately reduced the overall effectiveness of the interventions. The negative impact included entrenching corruption in intervention cycle, power disequilibrium between NDDC and Odi community, oppression and division, and gender inequality, commu-nal conflicts, and apathy. The Niger Delta Development Commission‘s interventions, intended for positive change, also had many negative consequences in Odi because the Commission failed to mainstream peace and conflict sensitivity in the interventions. The NDDC should therefore adhere strictly to its guiding principles and policies as well as international best practices in intervention programming in order to maximise the positive and minimise the negative impacts of its interventions. 1 results 1
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