Numerical Comparison of Line Search Criteria in Nonlinear Conjugate Gradient Algorithms

One of the open problems known to researchers on the application of nonlinear conjugate gradient methods for addressing unconstrained optimization problems is the influence of accuracy of linear search procedure on the performance of the conjugate gradient algorithm. Key to any CG algorithm is the computation of an optimalstep size for which many procedures have been postulated. In this paper, we assess and compare the performance of a modified Armijo and Wolfe line search procedures on three variants of nonlinear CGM by carrying out a numerical test. Experiments reveal that our modified procedure and the strong Wolfe procedures guaranteed fast convergence

Epidemiological Factors in Prevalence of Malaria Parasites in Primary Health Facilities Attendees, Ogun State, Nigeria

Malaria caused by Plasmodium species is often observed in areas where malaria is endemic. Malaria prevalence in metropolitan Abeokuta of Ogun State, Nigeria was studied between October, 2012 and January 2013. Oral interviews were used to get personal data of participants. Blood samples were obtained from 384 consented participants from the seven primary health centers. Blood film examination using Giemsa staining techniques was used to detect malaria parasites in the blood. From the 384 participants examined 273 (71.1%) were positive with malaria parasites. Species detected included Plasmodium falciparum (95.6%), Plasmodium malariae (3.3%), P. ovale (0.7%) and P. vivax (0.4%). The age-group 1-11 years had the highest malaria prevalence 94 (81%) while 51-60 had the least 6(54.5%). The malaria prevalence in relation to age was significant (p=0.011, p<0.05). The males 110 (73.8%) were slightly more affected than the females 163 (69.4%), but not statistically significant (p=0.347, p>0.05). Malaria prevalence was significantly higher among those with no formal education 80 (81.6%) and least among post-secondary educational. Prevalence among occupational groups showed significant difference, where the unemployed group were more infected and the retiree group had the least infection (p=0.014, p<0.05). The singles (56.4%) were more infected than the married (43.6%). The prevalence in relation to age was significant (p=0.000, p<0.05). The study has revealed that malaria disease can affect all age groups and both males and females’ sexes irrespective of their educational and occupational cadre. Public enlightenment efforts need to be intensified towards the prevention of malaria

Evaluation of Rapid Methods in Malaria Diagnosis from Persons attending Primary Health Facilities, Ogun State, Nigeria

Malaria in Nigeria is treated blindly in most cases and where diagnostic measures exist, efficacies of several are still in doubt. This study evaluated performance of microscopy and rapid (RDT) methods in confirming prevalence of malaria parasites (MP),parasite species and percent parasitized red blood cells in 384 persons systematically selected from seven primary healthcare facilities in Ogun State, Nigeria from October to December 2012. Giemsa thin and thick film techniques and RDT (SD Bioline Ag P.f/Pan kit) were employed on the blood samples. Data were analysed using SPSS version 16. Demographic results showed that females were 61% and males 39%,but of varying age groups. Seventy-one percent of the blood samples were positive for MP by microscopic blood films, and only 24% samples were positive by RDT. Paired sample T-test showed a significant difference (P=0.000)between microscopy and RDT methods. Of the 273 positive blood samples,95.6%were P. falciparum,3.3% were P. malariae, 0.7% was P. ovale and P. vivax (0.4%). For RDT, P. falciparum was 74% while mixed infections were 26%. Prevalence in risk groups 0–10 and 11–20 age groups was observed to be higher with significant differences (p=0.011, p=0.023) for both microscopy and RDT respectively. RDT sensitivity and specificity were 23.4% and 74.7% compared to microscopy. Positive Predictive Value and Negative Predictive Value were 69.6% and 28.4%. The efficiency of the RDT was 38.3%. The low sensitivity of RDT observed means that malaria diagnosis by microscopy method remains the gold standar

Evaluationof0 r M r 8 earthquake datasets in African – Asian regionduring1966–2015

Thisarticleevaluatestheoccurrenceof0 r M r 8 earthquakedata setsfortheperiodof50years(thatis,January1,1966toDecember 31,2015)inAfricanandWesternAsiaregion.Itisboundedby latitude40° S to40° N andlongitude30° W to60° E withthefocal depthof0–700km.Seventyseventhousand,sixhundredand ninety-sixdatapointswerepresentedfortheanalysis.Thedata usedwereextractedfromearthquakecatalogofAdvancedNational Seismicsystemvia http://quake.geo.berkeley.edu/cnss/, anofficial websiteoftheNorthernCaliforniaEarthquakeDataCentre,USA. Eachdatumcomprisedtheearthquakeoccurrencedate,timeofthe earthquakeoccurrence,epicenter’s coordinates,focaldepthand magnitude.TheGutenberg-Richter’s relationshipbeingthelongest observedempiricalrelationshipinseismology,analysisofvariance andtimeserieswereusedtoanalyzetheseismicityofthestudy area.Annualdistributionsofearthquakeoccurrencebasedon magnitudevariationswiththelimit0 r M r 8 werepresented. ThetwoconstantsaandbintheGutenberg-Richter’s equation, magnitudeofcompleteness(MC)adjustedR-Squareand F-valuefor theperiodof1966–1975,1976–1985,1986–1995,1996–2005,2006– 2015,andtheentireperiodofinvestigationrangingfrom1966t

Pathways for the Valorization of Animal and Human Waste to Biofuels, Sustainable Materials, and Value-Added Chemicals

Human and animal waste, including waste products originating from human or animal digestive systems, such as urine, feces, and animal manure, have constituted a nuisance to the environment. Inappropriate disposal and poor sanitation of human and animal waste often cause negative impacts on human health through contamination of the terrestrial environment, soil, and water bodies. Therefore, it is necessary to convert these wastes into useful resources to mitigate their adverse environmental effect. The present study provides an overview and research progress of different thermochemical and biological conversion pathways for the transformation of human- and animal-derived waste into valuable resources. The physicochemical properties of human and animal waste are meticulously discussed, as well as nutrient recovery strategies. In addition, a bibliometric analysis is provided to identify the trends in research and knowledge gaps. The results reveal that the USA, China, and England are the dominant countries in the research areas related to resource recovery from human or animal waste. In addition, researchers from the University of Illinois, the University of California Davis, the Chinese Academy of Sciences, and Zhejiang University are front runners in research related to these areas. Future research could be extended to the development of technologies for on-site recovery of resources, exploring integrated resource recovery pathways, and exploring different safe waste processing methods

Pathways for the Valorization of Animal and Human Waste to Biofuels, Sustainable Materials and Value-Added Chemicals

Human and animal waste, including waste products originating from human or animal digestive systems such as urine, feces, and animal manure, have constituted a nuisance to the environment. Inappropriate disposal and poor sanitation of human and animal waste often cause negative impacts on human health through contamination of the terrestrial environment, soil, and water bodies. Therefore, it is necessary to convert these wastes into useful resources to mitigate their adverse environmental effect. The present study provides an overview and research progress of different thermochemical and biological conversion pathways for the transformation of human- and animal-derived waste into valuable resources. The physicochemical properties of human and animal waste are meticulously discussed as well as nutrient recovery strategies. In addition, a bibliometric analysis is provided to identify the trends in research and knowledge gaps. The results reveal that the U.S.A, China and England are the dominant countries in the research areas related to resource recovery from human or animal waste. In addition, researchers from the University of Illinois, the University of California Davis, the Chinese Academy of Science and Zhejiang University are front runners in research related to these areas. Future research should be centred on developing technologies for the on-site recovery of resources, exploring integrated resource recovery pathways, and exploring different safe waste processing methods

A review of ceramic/bio-based hybrid reinforced aluminium matrix composites

The quest for light and durable materials which can withstand harsh conditions of modern advanced applications in many fields such as aviation, automobile, sport, and so on, has been scientifically sought for. Studies in the last few decades have found aluminium metal composites (AMCs) reinforced with bio-based fibres of diverse origins as a suitable advanced material because of improved physical and mechanical properties that are obtainable. Such reinforcements may be single (usage of one reinforcement) or hybridized (more than one reinforcement) with synthesized particulate materials; however, they impart better physico-mechanical and wear behavior on the aluminium alloy matrix. Thus, this review examines some of these composites produced by stir-casting procedures and their properties currently trending in materials research circles. It has been established that by varying parameters such as stirring speed/time and reinforcement types and composition, the use of stir casting process is a viable method to produce AMCs with good physical properties, mechanical properties, and wear behavior. AMCs are eminently useful in the production of parts for the automotive, aerospace and aviation industries

Image_2_Soil nutrient management influences diversity, community association and functional structure of rhizosphere bacteriome under vegetable crop production.JPEG

IntroductionRhizosphere bacterial communities play a crucial role in promoting plant and soil ecosystem health and productivity. They also have great potential as key indicators of soil health in agroecosystems. Various environmental factors affect soil parameters, which have been demonstrated to influence soil microbial growth and activities. Thus, this study investigated how rhizosphere bacterial community structure and functions are affected by agronomic practices such as organic and conventional fertiliser application and plant species types.MethodsRhizosphere soil of vegetable crops cultivated under organic and conventional fertilisers in different farms was analysed using high-throughput sequencing of the 16S rRNA gene and co-occurrence network pattern among bacterial species. The functional structure was analysed with PICRUSt2 pipeline.ResultsOverall, rhizosphere bacterial communities varied in response to fertiliser type, with soil physicochemical parameters, including NH4, PO4, pH and moisture content largely driving the variations across the farms. Organic farms had a higher diversity richness and more unique amplicon sequence variants than conventional farms. Bacterial community structure in multivariate space was highly differentiated across the farms and between organic and conventional farms. Co-occurrence network patterns showed community segmentation for both farms, with keystone taxa more prevalent in organic than conventional farms.DiscussionModule hub composition and identity varied, signifying differences in keystone taxa across the farms and positive correlations between changes in microbial composition and ecosystem functions. The organic farms comprised functionally versatile communities characterised by plant growth-promoting keystone genera, such as Agromyces, Bacillus and Nocardioides. The results revealed that organic fertilisers support high functional diversity and stronger interactions within the rhizosphere bacterial community. This study provided useful information about the overall changes in soil microbial dynamics and how the changes influence ecosystem functioning under different soil nutrient management and agronomic practices.</p

Image_5_Soil nutrient management influences diversity, community association and functional structure of rhizosphere bacteriome under vegetable crop production.JPEG

IntroductionRhizosphere bacterial communities play a crucial role in promoting plant and soil ecosystem health and productivity. They also have great potential as key indicators of soil health in agroecosystems. Various environmental factors affect soil parameters, which have been demonstrated to influence soil microbial growth and activities. Thus, this study investigated how rhizosphere bacterial community structure and functions are affected by agronomic practices such as organic and conventional fertiliser application and plant species types.MethodsRhizosphere soil of vegetable crops cultivated under organic and conventional fertilisers in different farms was analysed using high-throughput sequencing of the 16S rRNA gene and co-occurrence network pattern among bacterial species. The functional structure was analysed with PICRUSt2 pipeline.ResultsOverall, rhizosphere bacterial communities varied in response to fertiliser type, with soil physicochemical parameters, including NH4, PO4, pH and moisture content largely driving the variations across the farms. Organic farms had a higher diversity richness and more unique amplicon sequence variants than conventional farms. Bacterial community structure in multivariate space was highly differentiated across the farms and between organic and conventional farms. Co-occurrence network patterns showed community segmentation for both farms, with keystone taxa more prevalent in organic than conventional farms.DiscussionModule hub composition and identity varied, signifying differences in keystone taxa across the farms and positive correlations between changes in microbial composition and ecosystem functions. The organic farms comprised functionally versatile communities characterised by plant growth-promoting keystone genera, such as Agromyces, Bacillus and Nocardioides. The results revealed that organic fertilisers support high functional diversity and stronger interactions within the rhizosphere bacterial community. This study provided useful information about the overall changes in soil microbial dynamics and how the changes influence ecosystem functioning under different soil nutrient management and agronomic practices.</p