International Annals of Science
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The Solar Flux and Sunspot Number; A Long-Trend Analysis
Get PDFWe investigate the nature of monthly sunspot numbers and solar flux F10.7 by employing the linear and multiple regression techniques. We observed a brilliant correlation between monthly mean sunspot number and F10.7. We observed that even in deep solar minimum there exist some magnetic activities. We obtained the coefficient of determination R2 to be 0.9533. We estimated the correlation coefficient for solar flux F10.7 and sunspot number to be 0.97. We extrapolated the F10.7 back to the year 1700 and observed a good correspondence between the modelled F10.7 and sunspot nature. We also found a very good correspondence between the modelled and observed solar flux F10.7
Total Phenolic Contents and Antioxidant Variations in Raw and Cooked Dried Fruit of Xylopia aethiopica
Get PDFMost plant products undergo one or more different thermal processes before consumption despite the claims that cooking fruits and vegetables could have detrimental effects on the beneficial properties of the plants. This work investigated the changes in antioxidant status occurring in dried fruit of Xylopia aethiopica subjected to cooking at different temperatures. The analyses were performed on both raw and boiled samples to assess the total phenolic contents (TPCs) and the antioxidant potential through reduction of ferric chloride salt and bleaching of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The data obtained were subjected to analysis of variance and pairwise comparisons by Tukey-Kramer test at p < 0.05. There was a significant heat-trend difference between the phenolic contents of the samples at the selected temperatures with the highest TPC recorded at 70°C. Similarly, the ferric reducing potentials of the cooked samples were significantly different (p <0.05) from the raw. However, uncooked samples had significantly (p <0.05) higher percentage of DPPH radical scavenging activity compared to cooked samples. The overall effect of cooking the dried fruit of X. aethiopica was due to an elevation in total phenolics concentrations and reducing potentials of the aqueous infusions. However, boiling decreases the DPPH radical scavenging ability of the samples. Therefore, this study suggests an optimum cooking temperature of 70°C which could result in the highest retention of phenolic contents and ferric reducing potentials in the fruit of X. aethiopica and lowest appropriate temperature to conserve its intrinsic radical-scavenging activity in order to assure a higher quality food for the maintenance of human health. Moreover, losses in the phenolic contents and antioxidant potential should be considered when the procedural temperature during processing is unalterable
Biosorption of an Anionic Dye, Eosin Yellow onto Pineapple Peels: Isotherm and Thermodynamic Study
Get PDFEosin Yellow (EY), an anionic dye (acid dye) was adsorbed using an agricultural waste, pineapple peels (PP) as bio-sorbent in order to investigate its suitability as an alternative adsorbent, and to give insight into the mechanisms of binding. The study includes: equilibrium isotherms and thermodynamics studies. The adsorption isotherm and thermodynamics experiments were conducted using batch equilibrium techniques. The adsorption data were fitted into Langmuir, Freundlich and Temkin isotherm models; as a result, the data fitted well into the Langmuir model from which the adsorption capacity, qe was obtained as 11.76 mg/g. Experimental values of the thermodynamics parameters (ΔH, ΔS and ΔG) and separation factor (RL) in combination suggested that the adsorption process was endothermic, feasible, spontaneous, and had high degree of freedom. Combined results of the isotherms and thermodynamic study suggested a physisorption-chemisorption mechanism for the adsorption process. Therefore, the results of the study could provide useful information to evaluate the raw pineapple peel powder as a cheap source of adsorbent for the removal of EY from waste water
Comparative Study of the in vitro Antioxidant Properties of Methanolic Extracts of Chromolaena odorata and Ageratum conyzoides used in Wound Healing
Get PDFThis study sought to evaluate the potential antioxidative potencies of Chromolaena odorata and Ageratum conyzoides, commonly used herbs in Nigeria for wound first aid and healing. The antioxidant potentials were evaluated by measuring their abilities to scavenge radicals, reduce oxidised iron and quench the formation of lipid peroxides. The findings showed that the extract of Ageratum conyzoides exhibited significantly higher (p<0.05) antioxidant potential than the extract of Chromolaena odorata. The study therefore suggests that Ageratum conyzoides has higher potential for therapeutic value than Chromolaena odorata in terms of antioxidant potential
Periodic Solution and Stability Behavior for Nonlinear Oscillator Having a Cubic Nonlinearity Time-Delayed
Get PDFThe current paper investigates the dynamics of the dissipative system with a cubic nonlinear time-delayed of the type of the damping Duffing equation. A coupling between the method of the multiple scales and the homotopy perturbation has been utilized to study the complicated dynamic problem. Through this approach, a cubic nonlinear amplitude equation resulted in at the first-order of perturbation; meanwhile, a quintic equation appears at the second-order of perturbation. These equations are combined into one nonlinear quintic Landau equation. The polar form solution is used, and linearized stability configuration is applied to the nonlinear amplitude equation. Also, a second-order approximate solution is achieved. The numerical illustrations showed that the damping, delay coefficient, and time delay play dual roles in the stability behavior. In addition, the nonlinear coefficient plays a destabilizing influence
Comparative Growth Response of Three Jatropha Species on Heavy Metal Contaminated Soil
Get PDFThis study investigated the comparative phytotoxcity effect of heavy metal contamination on Jatropha curcas, Jatropha gossypifolia and Jatropha multifida in contaminated soil from a dump site in Ibadan Nigeria. Seeds of J. curcas, J. gossypifolia and J. multifida were planted in a germination tray and later transplanted into polythene pots filled with 2kg of either control soil or heavy metal contaminated soil, a 3 × 2 factorial experiment laid out in complete randomized design (CRD) replicated four times was adopted; treatments imposed include T1 – J. curcas/Control Soil, T2 – J. gossypifolia/Control Soil, T3 – J. multifida/Control Soil, T4 – J. curcas/Contaminated soil, T5 – J. gossypifolia/Contaminated Soil, and T6 – J. multifida/Contaminated Soil. Weekly variation in growth parameters: the plant height, leave production and stem diameter were measured over the course of 12 weeks. The growth parameters were dependent on a combination of both specie type and level of heavy metal contamination of soil. J. multifida (T3) (36.93cm) performed best, comparable with J. gossypifolia (T2) (34.1cm) after 12 weeks while J. multifida (T6) had the lowest mean plant height (7.23cm) which is not significantly (p<0.05) different from other species on the contaminated soil; for leave production, J. gossypifolia (T2) produced the highest mean number of leaves (9.67) which is comparable with J. multifida (T3) (9.00) and less so with J. curcas (T1) (6.67) with significant leave losses on the contaminated soils after 12 weeks; variation in stem diameter shows that J. curcas (T1) had the highest stem girth (1.96 mm) which is comparable to the value obtained for J. curcas (T4) (1.95mm), while J. multifida (T6) had the lowest stem girth (1.09 mm). J. gossypifolia (T2) and J. multifida (T3) had comparable stem girth of 1.57mm and 1.47mm respectively. Toxicity of heavy metals in the contaminated soil greatly affect the growth parameters of the Jatropha
Contemporary Issues of Climate Change on Oil and Gas Industry Operations
Get PDFThe reality of climate change as an aspect of broader global and environmental change attributable to either natural or anthropogenic cause is becoming more evident. Equally, energy, chiefly oil and gas is not only a major climate change inducer via greenhouse gas emissions anymore, but also a victim of the impacts therein. As such, this paper examines the impact of recorded changes in climatic variables on oil and gas operations categorized into upstream, midstream and downstream operations representing exploration and production, transportation, along with processing and distribution respectively. Identified changes in weather events primarily driven by general climate change having significant impact on oil and gas operations and infrastructure include increasing temperature, increasing flooding, storm surges, sea level rise, coastal erosion, intense winds and waves, drought/water shortage and subsidence/landslides/mudslides and they all pose tremendous risk to onshore and offshore (shallow and deep water) operations and installations. Several adaptation measures are currently being implemented some of which are already yielding positive results. Adaptation measures are being complemented with mitigation strategies as long-term solutions. Sadly, most developing oil producing countries are still way behind in adopting various existing adaptation measures and implementing mitigative strategies due to prevalent low capacity
Biological Control of Anthracnose Disease of Tomato Using Ethanolic Extracts of Azadirachta Indica and Nicotiana Tabacum
Get PDFTomato is a commercially important vegetable throughout the whole world and its availability all the year is grossly affected by anthracnose disease, hence, the need for an effective bio-control that is affordable and user friendly. This study therefore investigated the inhibitory effect of ethanol extracts of Azadirachta indica and Tabacum nicotianaon the mycelium growth of fungi associated with anthracnose disease of tomato. Tomatoes that showed black circular lesions with concentric ring and black spores were bought from Aleshinloye market in Ibadan; samples (3×3mm) from the sterilized margin of the lesion were inoculated on potato dextrose agar and observed for mycelium growth for five days. The obtained cultures were then sub cultured to obtain pure cultures which were introduced into healthy tomato fruits to confirm koch’s postulate. The in-vitro antifungal effects of ethanol extracts of Azadirachta indica and Nicotiana tabacum on isolated fungus causing anthracnose disease of tomato was investigated using agar dilution method. Based on cultural and microscopic characteristics of conidia, Colletotrichum coccodewas identified as organism causing anthracnose disease of tomato. The antifungal effect of the two ethanol plant extracts revealed that Azadirachta indica had the highest inhibitory effect of (45.00cm) at 100mg/ml and the least effect of (38.00cm) at 50mg/ml. Nicotiana tobacum equally had its highest inhibitory effect of (58.00cm) at 100mg/ml and lowest effect of (40.57cm) at 50mg/ml. This result also showed that Nicotiana tobacum had the highest inhibitory effect on Colletotrichum coccode than Azadirachta indica. Conclusively, the use of Tobacco and Neem plant extracts has antifungal activity against Colletotrichum which is responsible for Anthracnose disease of tomato. The plant could be a veritable and cheaper substitute for conventional drugs since the plant is easily obtainable and the extract can easily be made via a simple process of maceration or infusion
Phytominerals and Phytochemical Studies of Azadiracthta indica, Leea guineensis and Parkia biglobosa Leaves
Get PDFMedicinal plants have great importance in African medicine and are also used as precursors in drug discovery. The medicinal value of plants lie in their bioactive constituents which usually allow them to fight against several diseases. Plant-based natural constituents can be derived from any part of the plant like bark, leaves, flowers, roots, fruits, seeds. The mineral and phytochemical analysis of the leaves of Azadirachta indica, Parkia biglobosa and Leea guineensis were investigated. The leaves were collected from the Herbal Garden, Forestry Research Institute of Nigeria, Jericho hills, Ibadan, Nigeria and identified at Forest Herbarium Ibadan. Oyo State. The leaves were air dried and milled to powder using a medium-sized milling machine and stored in an air-tight container until needed for analysis. Phytochemical screening/analysis and mineral analysis were determined using standard analytical methods. Phytochemicals like Alkaloids, Flavonoids, Tannins, Saponins, Anthraquinone, Cardiac glycoside were determined. while Minerals, such as Potassium, Sodium determined using flame photometer; Calcium, Phosphorus, Magnesium, Iron, Zinc, Manganese, and Copper were determined using Atomic Absorption Spectrophotometer. Results indicates that the bioactive contents of the leaves varied significantly (p<0.05) among the medicinal plants. The phytochemical analysis showed that the three medicinal plants contained alkaloid, saponins, tannins, flavonoids, polyphenols, cardiac glycoside and anthraquinone in varying quantities with the trend: A indica > P. biglobosa > L. guineensis; the macro elements showed similar trend as the phytochemicals while the micro elements followed the trend: P. biglobosa > L. guineensis > A indica. These results conceivably indicate that the three medicinal plant are good source of essential minerals and phyto-nutrients which possess strong pharmacological activities and provide scientific credence for its therapeutic usage
Antibiotic Susceptibility Profiles of Bacteria from Diabetic Foot Infections in Selected Teaching Hospitals in Southwestern Nigeria
Get PDFOne of the serious complications associated with diabetes is foot ulcer and this condition affects the quality of life in patients in all classes, races and ages. Chronic wounds are prone to colonization by wide array of microorganisms which could be extremely hazardous to patients if effective and timely therapeutic intervention is not made. This study was conducted to determine the antibiotic susceptibility profiles of bacteria from diabetic foot infections in southwestern Nigeria. Samples were collected from a total of 142 diabetic foot ulcer patients with moistened sterile cotton swabs. Nutrient agar, Mac-Conkey agar, blood agar and mannitol salt agar media were used for the isolation of total viable bacteria, Gram-negative non-spore forming lactose fermenters, fastidious bacteria and staphylococci, respectively. Morphological and biochemical characteristics of pure cultures were determined in accordance with standard laboratory criteria. API 20 E and API 20 NE were used for the confirmation of identity of the bacterial isolates. The disc diffusion technique was employed for the determination of antibiotic susceptibility of bacterial isolates in accordance with standard procedures. The antibiotics investigated included amikacin, amoxicillin, ampicillin, ceftazidime, cefazolin, ceftriaxone, chloramphenicol, ciprofloxacin, clindamycin, gentamicin, imipenem, linezolid, methicillin, netilmicin, ofloxacin, oxacillin, penicillin, piperacilin, sulfamethoxazole, trimethoprim and vancomycin. One hundred and seventy-seven isolates were encountered and these were characterized into eleven bacterial species. These included Staphylococcus aureus (22.03%), Pseudomonas aeruginosa (16.95%), Staphylococcus epidermidis (12.43%), Proteus mirabilis (8.48%), Klebsiella pneumoniae (7.91%), E. coli (7.35%), Staphylococcus saprophyticus (6.78%), Streptococcus pyogenes (5.65%), Morganella morganii (5.09%), Citrobacter freundii (4.52%) and Acinetobacter baumannii (2.83%). Gram-negative bacteria showed 76.99% susceptibility to the antibiotics while 22.85% was resistant. Gram-positive bacteria showed 93.75% susceptibility and 5.01% resistance to the antibiotics. This study revealed that there is no definite aetiologic bacterial agent for diabetic foot infections and many of the associated bacteria are sensitive to certain antibiotics