Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood plasma.Meth...Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood plasma.Methods:Oxidative stress was induced by oral administration of ethanol(20%w/v) at a dosage of 5 niL/kg bw in rats.After 28 days of treatment,the rats were fasted overnight and sacrificed by cervical dislocation.Blood was collected with a 2 mL syringe by cardiac puncture and was centrifuged at 3000 rpm for 10 min.The plasma was analyzed to evaluate malondialdehyde(MDA),catalase activity,aspartate aminotransferase(AST),alkaline phosphatase(ALP) and alanine aminotransferase(ALT) concentrations.Results:Administration of alcohol caused a drastic increase(87.74%) in MDA level compared with the control.Pineapple peel extract significantly reduced the MDA level by 60.16%at 2.S mL/kg bw.Rats fed alcohol only had the highest catalase activity,treatment with pineapple peel extract at 2.5 mL/kg bw however, reduced the activity.Increased AST,ALP and ALT activities were observed in rats fed alcohol only respectively,treatment with pineapple peel extract drastically reduced their activities. Conclusions:The positive modulation of lipid peroxidation,catalase activities as well as hepatic biomarker levels of blood plasma by the methanolic extract of pineapple peels under alcoholinduced oxidative stress is an indication of its protective ability in the management of alcoholinduced toxicity.展开更多
The basic goal of accounting is to provide quality accounting information that will aid reliable decision-making. The quality level of this accounting information comes from the company＇s governance practices, thereb...The basic goal of accounting is to provide quality accounting information that will aid reliable decision-making. The quality level of this accounting information comes from the company＇s governance practices, thereby emphasizing the importance of corporate governance in companies. Recently, following the financial crises resulting in accounting scandals, attention has been moving towards internal audit function as an important factor in the structure of corporate governance. This paper therefore examined the extent of the relationship between internal audit function and the quality of accounting information of companies. The study adopted the survey research design. The research instrument employed was questionnaire which was administered to internal auditors of the ＂Big Four＂. Linear regression analysis was employed in the analysis of the data collected with the use of Statistical Packages for Social Sciences （SPSS）. The results revealed that there is a significant relationship between the internal audit characteristics and the quality of accounting information. It was recommended that in order to provide credibility to the financial statement, there should be a law in place mandating attachment of internal auditors report to the financial statement.展开更多
Theductility and hardness of AA6011/SiCp composites using NaCl, SnCl2, NH4Cl and PdCl2 as wetting reagents were investigated. SiCp was cleaned with the wetting reagents, and used as reinforcement in AA6011 alloy using...Theductility and hardness of AA6011/SiCp composites using NaCl, SnCl2, NH4Cl and PdCl2 as wetting reagents were investigated. SiCp was cleaned with the wetting reagents, and used as reinforcement in AA6011 alloy using the stir casting method. Ductility and hardness responses of the composites were measured using standard methods. Microstructural features were examined using scanning electron microscopy and the phases were determined with the help of an X-ray diffractometer. The results show that for all wetting agents, the increase in cleaning time leads to initial increase in ductility to a certain value, but a decrease afterwards with further increase in cleaning time. The best combination of hardness （BHN 57.88） and ductility （11.91%） was shown under conditions of 40 g/L SnCl2and cleaning time of 60 min. A minor formation of Al4C3was noted in diffraction patterns, indicating that the formation of deleterious precipitate was hindered by the cleaning process.展开更多
The effect of commercial enzymes on quality of wort developed from replacement of malted barley (100%) with sorghum as adjunct 50%, 60%, 70%, and 80% was investigated for pH, colour, filteration rate, extract asin, dr...The effect of commercial enzymes on quality of wort developed from replacement of malted barley (100%) with sorghum as adjunct 50%, 60%, 70%, and 80% was investigated for pH, colour, filteration rate, extract asin, dry extract, viscosity, total soluble nitrogen and free amino nitrogen. The wort pH (5.6 - 6.0) is relatively stable with no significant changes at all levels of replacements. The colour is lighter with increment in proportion of the sorghum as it appears as colour diluents. Wort filteration rate is reduced with the sorghum replacement and the wort produced tends to be turbid which affects the utilization of the wort. The total soluble nitrogen and free amino nitrogen value increased with the use of commercial enzymes while the viscosity decreases with enzymes. The use of ceremix and cereflo have been found to be relatively more effective in the preparation of beer wort as observed for the result obtained in proportions of sorghum and malt barley. The use of high percentage sorghum as adjunct with commercial enzymes are found to be useful in production of high quality wort with low cost and profitability.展开更多
<span style="line-height:1.5;"><span style="font-family:Verdana;">An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antio...<span style="line-height:1.5;"><span style="font-family:Verdana;">An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antioxidant systems possessed by living or</span><span style="font-family:Verdana;">g</span><span style="font-family:Verdana;">anisms are generally not enough to prevent them from oxidati</span><span style="font-family:Verdana;">ve damage</span><span style="font-family:Verdana;">s and the use</span></span><span style="line-height:1.5;font-family:Verdana;">s</span><span style="line-height:1.5;font-family:Verdana;"> of synthetic antioxidants also ha</span><span style="line-height:1.5;font-family:Verdana;">ve</span><span style="line-height:1.5;font-family:Verdana;"> some harmful effects. T</span><span style="line-height:1.5;"><span style="font-family:Verdana;">his study was aimed at evaluating the antioxidant activities of exopolysaccharides p</span><span style="font-family:Verdana;">roduced by lactic acid bacteria isolated from yoghurt. Lactic acid bac</span><span style="font-family:Verdana;">teria (LAB) were isolated from six different brands of commercially available yoghurt using deMan Rogosa Sharpe (MRS) agar. The LAB isolates were identified based on morphological and biochemical analyses and were screened for exopolysaccharide (EPS) production. The LAB isolates screened positive were used for EPS production in a liquid medium and the EPS produced were purified and quantified using standard methods. Antioxidant activities of the E</span><span style="font-family:Verdana;">PS were evaluated by determining the 1,1-dip</span><span style="font-family:Verdana;">henyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric ion reducing power, and total phenolic contents. Data obtained were analysed using Analysis of Variance. Total lactic acid bacterial count obtained from the yoghurt samples ranged from 0 - 3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL with sample A (Fan Yoghurt) having the highest LAB count (3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL). The isolated LAB and their incidence rate were </span><i><span style="font-family:Verdana;">Lactobacillus plantarum </span></i><span style="font-family:Verdana;">(25.49%),</span><i><span style="font-family:Verdana;"> L. delbrueckii </span></i><span style="font-family:Verdana;">(19.61%),</span><i><span style="font-family:Verdana;"> L. fermentum </span></i><span style="font-family:Verdana;">(15.69%),</span><i><span style="font-family:Verdana;"> L. acidophilus </span></i><span style="font-family:Verdana;">(13.73%), </span><i><span style="font-family:Verdana;">Leuconostoc mesenteroides </span></i><span style="font-family:Verdana;">(11.76%),</span><i><span style="font-family:Verdana;"> Lactococcus lactis </span></i><span style="font-family:Verdana;">(7.84%), and </span><i><span style="font-family:Verdana;">Lactobacillus casei </span></i><span style="font-family:Verdana;">(5.88%). Fifty-one out of the 64 LAB isolates were screened positive for EPS production and only six were able to produce substantial quantity of EPS ranging from 127.4 - 208.5 mg/L. The exopolysaccharides produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> had the highest DPPH radical scavenging activity (62.90%) while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (23.10%) at a concentration of 1000 μg/mL. Also, the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> recorded the highest ferric ion reducing power (12.89 mg AAE/mL) at 1000 μg/mL while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (5.62 mg AAE/mL). At 1000 μg/mL, the total phenolic contents of the EPS samples ranged from 1.41 - 1.58 mg GAE/mL, and the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum </span></i><span style="font-family:Verdana;">had the highest (1.58 mg GAE/mL) while those produced by </span><i><span style="font-family:Verdana;">L. paracasei </span></i><span style="font-family:Verdana;">had the lowest (1.41 mg GAE/mL). This study revealed that the exopolysaccharides produced by the LAB isolates showed high antioxidant activities with respect to their DPPH free radical scavenging activity, ferric ion reducing power and total phenolic contents.展开更多
<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococ...<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococcus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> is reported severally to be resistant to the drugs often used empirically for treatment of urinary tract infections (UTIs). Their ability to exhibit resistance to multiple drugs is a great de</span><span style="font-family:Verdana;">al of threat to successes recorded in the management of UTIs cause</span><span style="font-family:Verdana;">d by this pathogen. Lactic acid bacteria (LAB) have been demonstrated to exhibit an</span><span style="font-family:Verdana;">timicrobial activities but studies about their prospect against multi</span><span style="font-family:Verdana;">-drug resistant </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> are quite few. This study therefore investigated acti</span><span><span style="font-family:Verdana;">vities of LAB against the multi-drug resistant </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> recover</span></span><span style="font-family:Verdana;">ed fro</span><span style="font-family:Verdana;">m urine samples of symptomatic women. The three differ</span><span style="font-family:Verdana;">ent species of LAB </span><span><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 62, </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 86 and </span><i><span style="font-family:Verdana;">Weis</span></i></span><i><span style="font-family:Verdana;">sella</span></i><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> BTA 40) previously isolated and identified by 16S rRNA s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;">quencing were selected based on their history of antimicrobial activities. Their</span><span style="font-family:Verdana;"> m</span><span style="font-family:Verdana;">etabolites were employed in the antagonistic assays against six (6) mu</span><span style="font-family:Verdana;">lti-drug resista</span><span style="font-family:Verdana;">nt test pathogens recovered fro</span><span style="font-family:Verdana;">m urine samples of symptomatic, non-pregnant women attending clinics in Lagos, Nigeria and the control (</span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> subs bovis strain DSM 18669) following standard procedures. </span><span style="font-family:Verdana;">The pathogens showed resistances to almost all the antibiotics except</span><span style="font-family:Verdana;"> levofloxaci</span><span style="font-family:Verdana;">n, ciprofloxacin, imipenem while the control showed resistance to thr</span><span style="font-family:Verdana;">ee. The LAB, </span><i><span style="font-family:Verdana;">L.</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> inhibited five (83.3%) of the pathogens with zone diameter of 12 - 17 mm, followed by </span><i><span style="font-family:Verdana;">W</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> inhibiting three (50%) with 15 - 17 mm. </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> on the other hand, inhibited a pathogen and the control with zones of 13 mm and 14 mm respectively. In conclusion, the extracted metabolites of LAB inhibited the growth of multi-drug resistant clinical isolates of uropathogenic </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> and may therefore be potent alternatives to antibiotics.</span></span>展开更多
In this study, Natural Raw Kaolinite (NRK) clay was used as an adsorbent for the investigation of the adsorption kinetics, isotherms and thermodynamic parameters of a cationic dye Safranine-O, also known as Basic Red ...In this study, Natural Raw Kaolinite (NRK) clay was used as an adsorbent for the investigation of the adsorption kinetics, isotherms and thermodynamic parameters of a cationic dye Safranine-O, also known as Basic Red 2 (BR2) from aqueous solution. The effects of pH, temperature, initial dye concentration and contact time on the adsorption capacity were evaluated and the adsorbent was characterized by XRD, BET and FTIR. The pseudo-first-order, pseudo-second-order kinetic models and the intraparticle diffusion model were used to describe the kinetic data and the rate constants were evaluated. The experimental data fitted very well with the pseudo-second-order kinetic model and also followed intraparticle diffusion model revealing that diffusion is not only the rate-controlling step. The Langmuir Freundlich and Dubinin-Radushkevic adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were also determined. The Langmuir model agrees with experimental data well. The activation energy, change of Gibbs free energy, enthalpy and entropy of adsorption were also evaluated for the adsorption of BR2 onto NRK.展开更多
Objective: To characterize the genetic diversity of Plasmodium falciparum ( P. falciparum ) field isolates in children from Lafia, North-central Nigeria, using the highly polymorphic P. falciparum merozoite surface pr...Objective: To characterize the genetic diversity of Plasmodium falciparum ( P. falciparum ) field isolates in children from Lafia, North-central Nigeria, using the highly polymorphic P. falciparum merozoite surface protein 2 (MSP-2) gene as molecular marker. Methods: Three hundred and twenty children were enrolled into the study between 2005 and 2006. These included 140 children who presented with uncomplicated malaria at the Dalhatu Araf Specialist Hospital, Lafia and another 180 children from the study area with asymptomatic infection. DNA was extracted from blood spot on filter paper and MSP-2 genes were genotyped using allele-specific nested PCR in order to analyze the genetic diversity of parasite isolates. Results: A total of 31 and 34 distinct MSP-2 alleles were identified in the asymptomatic and uncomplicated malaria groups respectively. No difference was found between the multiplicity of infection in the asymptomatic group and that of the uncomplicated malaria group ( P >0.05). However, isolates of the FC27 allele type were dominant in the asymptomatic group whereas isolates of the 3D7 allele type were dominant in the uncomplicated malaria group. Conclusions: This study showed a high genetic diversity of P. falciparum isolates in North-central Nigeria and is comparable to reports from similar areas with high malaria transmission intensity.展开更多
Objective:To investigate the ability of the methanolic extract of pineapple peel to attenuate alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues. Methods:Oxidative stress was induce...Objective:To investigate the ability of the methanolic extract of pineapple peel to attenuate alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues. Methods:Oxidative stress was induced by oral administration of ethanol(20%w/v) at a dosage of 5 mL/kg bw in rats.After 28 days of treatment,the rats were fasted overnight and sacrificed by cervical dislocation.Brain tissues were assayed for total phospholipid(TP) content and malondialdehyde(MDA).Results:Administration of alcohol significantly caused a reduction in TP content.Treatment with pineapple peel extract significantly increased the TP content. Significant high levels of MDA was observed in alcohol-fed rats,treatment with pineapple peel extract significantly reduced the MDA levels.Conclusions:Results obtained from this study indicates that pineapple peel extract protects against alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues.展开更多
The occurrence of earthquakes in oceanic tren- ches can pose a tsunami threat to lives and properties in active seismic zones. Therefore, the knowledge of focal depth, magnitude, and time distribution of earthquakes a...The occurrence of earthquakes in oceanic tren- ches can pose a tsunami threat to lives and properties in active seismic zones. Therefore, the knowledge of focal depth, magnitude, and time distribution of earthquakes along the trenches is needed to investigate the future occurrence of earthquakes in the zones. The oceanic trenches studied, were located from the seismicity map on： latitude ＋51 ° to＋53° and longitude -160° to 176° （Aleutian Trench）, latitude ＋40° to ＋53° and longitude ＋148° to＋165° （Japan Trench）, and latitude -75° to -64° and longitude -15° to ＋30° （Peru-Chile Trench）. The following features of seis- mic events were considered： magnitude distribution, focal depth distribution, and time distribution of earthquake. The results obtained in each trench revealed that the earthquakes increased with time in all the regions. This implies that the lithospheric layer is becoming more unstable. Thus, tectonic stress accumulation is increasing with time. The rate of increase in earthquakes at the Peru-Chile Trench is higher than that of the Japan Trench and the Aleutian Trench. This implies that the convergence of lithospheric plates is higher in the Peru-Chile Trench. Deep earthquakes were observed across all the trenches. The shallow earthquakes were more prominent than intermediate and deep earthquakes in all thetrenches. The seismic events in the trenches are mostly of magnitude range 3.0-4.9. This magnitude range may indi- cate the genesis of mild to moderate tsunamis in the trench zone in near future once sufficient slip would occur with displacement of water column.展开更多
Carbide precipitates in Thin Wall Ductile Iron (TWDI) used for automotive applications needs to be eliminated or reduced for improved strength, ductility, crack propagation resistance and good machinability. Ductile i...Carbide precipitates in Thin Wall Ductile Iron (TWDI) used for automotive applications needs to be eliminated or reduced for improved strength, ductility, crack propagation resistance and good machinability. Ductile iron thin section profiles (≤3 mm) present danger of massive carbide precipitations in the as-cast sample. Precipitated carbide phase is brittle and negatively affects the mechanical properties of the iron matrix. The suppression of carbide formation is associated with the nucleating properties of the nodularizer and innoculant alloys. This treatment is vital in ensuring that carbide precipitation, flake graphite structure and non-nodular graphite phases are reduced or completely eliminated in the TWDI castings. Therefore, the temperature and technique of treatment would influence the yield of the process, and ultimately the mechanical properties. In this study, the effect of nodularization and inoculation treatment temperature on the microstructure and mechanical properties of TWDI castings is examined. The results indicate that good nodularity and nodule count with better percent elongations are achieved using low treatment temperatures in descending order of 1490°C, 1470°C and 1450°C, but have negative effect at lower treatment temperature of 1430°C. However, TWDI castings have superior properties in terms of nodule counts and nodularity at 1450°C. Treatment temperature does not produce significant influence on ultimate tensile strength (UTS) and hardness of TWDI castings. TWDI castings show poor nodularity, nodule count and ductility at higher inoculation treatment temperatures of 1550°C, 1530°C and 1510°C.展开更多
Previous genetic studies in cowpea [Vigna unguiculata (L.) Walp] have shown that an active bipartite transposable element (TE) is responsible for a range of mutant phenotypes of its leaf, stem and flower. Since type I...Previous genetic studies in cowpea [Vigna unguiculata (L.) Walp] have shown that an active bipartite transposable element (TE) is responsible for a range of mutant phenotypes of its leaf, stem and flower. Since type II TEs have not been characterized at the molecular level in cowpea, this study was initiated to survey the presence of type II TEs in the cowpea genome. Type II TEs: Enhancer/Suppressor-mutator (En/Spm) and Miniature Inverted-repeat Transposable Elements (MITEs) were isolated and characterized. The sequence identity between the EnSpm TE clones was 46% at the nucleotide level (NL) and 30% at the amino acid level (AL) while that of MITEs was 71% at NL and 63% at AL. These cowpea En/Spm TEs were 80% homologous with En/Spm elements of other crops at NL and 46% at AL. The MITEs were 96% similar at NL and 18% homologous at AL. DNA gel blot analysis confirmed the presence of the En/Spm TEs in cowpea. RT-PCR (reverse transcriptase polymerase chain reaction) analysis showed that the VuEnSpm-3 and the MITE clone, VuPIF-1 were actively transcribed in wild type and mutant cowpea tissues. Overall, our data show that multiple, divergent lineages of En/Spm and MITEs are present in the cowpea genome, some of which are actively transcribed. Our findings also offer new molecular resource to further investigate the genetic determinants underlying previously described mutant cowpea phenotypes.展开更多
Nigeria is an agglomeration of different ethnic nationalities with multiplicity of religious inclination where Christianity and Islam are the dominant.The high level of intra and inter-ethnic rivalry between ethnic na...Nigeria is an agglomeration of different ethnic nationalities with multiplicity of religious inclination where Christianity and Islam are the dominant.The high level of intra and inter-ethnic rivalry between ethnic nationalities and extreme religious intolerance has resulted in many catastrophic clashes.These clashes have unquantifiable debilitating effects on the equilibrium of housing supply and delivery.The paper through deductive approach from literature review,and descriptive analysis,examined the various ethno-religious violence from post-independence Nigeria and its implications on the housing sector.Findings revealed that the importance of houses in African settings is beyond mere shelter,but are sacred and generational assets worth bequeathing.This underscores the reason it becomes target for attacks during ethno-religious violence.Deductive inferences made,indicated that the greater the severity of the violence on houses the more the number of IDPs(internally-displaced-persons),and this not healthy for a sustainable urban housing growth.展开更多
The nutritional, microbiological and sensory characteristics of improved kunu-zaki produced from malted cereals enriched with malted soymilk at different substitution levels (0% - 30%) were investigated. Enrichment wi...The nutritional, microbiological and sensory characteristics of improved kunu-zaki produced from malted cereals enriched with malted soymilk at different substitution levels (0% - 30%) were investigated. Enrichment with soymilk and malting increased the protein, amino acid, ash and moisture content of the improved kunu-zaki. Malting resulted in a decrease in carbohydrate and fat content. The protein content of the malted samples ranged between 2.79% and 3.82% while that of unmalted was 2.36%. There was decrease in the concentration of phytic acid and trypsin inhibitor after malting but the concentration increased as soymilk was added. Microbiological analyses showed that microbial load of samples increased with the addition of soymilk. There was a significant difference (p 0.05) in the sensory attributes, acceptability decrease with increase in soymilk addition because of the beany flavor.展开更多
The challenges facing public schools are multifaceted and include: teachers dissatisfaction, non-commitment of educators, chronic absenteeism by educators, low morale, poor work ethics by educators, late coming of bot...The challenges facing public schools are multifaceted and include: teachers dissatisfaction, non-commitment of educators, chronic absenteeism by educators, low morale, poor work ethics by educators, late coming of both educators and learners, overcrowding in classes, lack of technical resources and many more. A cursory investigation of public secondary school buildings in Ado-Odo/Ota L.G.A shows its deplorable conditions of structural, aesthetical and decorative disrepair. Therefore the paper focused on examining users “perception of the present deplorable physical condition and neglect of public secondary school. The study engaged the use of quantitative method of analysis, employing the use of questionnaire administered randomly and distributed face-to-face to targeted despondences”. The result of findings revealed performance/productivity of building users depends largely on working and learning condition of building. The outcomes of the research would help policy makers, facilities maintenance experts and professionals alike to device a policy for regular maintenance of public building in other to enhance performance and increase productivity amongst users.展开更多
The increasing demand for airline services amidst limited resources results in passenger dissatisfaction and dwindling revenue for airports and airlines. The dynamics of service demand and resource supply results in c...The increasing demand for airline services amidst limited resources results in passenger dissatisfaction and dwindling revenue for airports and airlines. The dynamics of service demand and resource supply results in check-in issues for the stakeholders in the commercial aviation industry. This has the effect of impacting negatively on service performance, cost of operations, customer satisfaction, and overall throughput. Hence, this paper modelled the travelers’ check-in process at the “D Wing” of the Departure Section of Murtala Muhammed International Airport (MMIA), Ikeja, using Arena Software Tool. The work was carried out by determining the parameters of the queues at designated service points in the check-in process. The primary data required to develop the model were acquired by direct observation of passenger flow and oral interview. Thus, the average check-in time was determined. Thereafter, a model of the international check-in system of the MMIA was developed using Arena software in combination with Microsoft Office tools. The data collected were therefore inputted into the model and simulated;the real result was compared with the simulation result of 133 completions and there was no significant difference. The result showed that the model is a representation of the real system under study. Further work will be tailored towards simulation (<em>i.e</em>. the model will be subjected to experimentation in order to have different scenario).展开更多
With the current situation of insecurity in Nigeria and the worsening condition of Nigerian roads, there is increasing demand for air travel. This increasing demand for airline services amidst limited resources result...With the current situation of insecurity in Nigeria and the worsening condition of Nigerian roads, there is increasing demand for air travel. This increasing demand for airline services amidst limited resources results in passenger dissatisfaction and reduction of revenue for airports and airlines. The dynamics of service demand and resource supply result in check-in issues for all the stakeholders in the commercial aviation industry. Hence, this research simulated the developed model for travelers’ check-in process at the “D Wing” of the Departure Section of Murtala Muhammed International Airport (MMIA), Ikeja, using Arena Software Tool. The simulation of the developed model was carried out by varying five different configurations of the servers with respect to the baggage weighing machines and passenger profiling devices to obtain the minimum average check-in time (ACT) for the process, with each configuration undergoing 133 completions of simulation runs. The result of the experimentation revealed that the 3 × 3 × 4 configuration of servers produced the smallest ACT of 18.25 minutes. This translates to a difference of about 58 minutes from the 76.16 minutes ACT of the real system;representing about 76% improvement in the check-in time of passengers. This study contributed to knowledge by revealing that the main choke points in the MMIA check-in system occur at the baggage weighing and passenger profiling areas as against the check-in counter sub-section as advanced by previous works. Furthermore, the research added value to knowledge by creating a balance between customer satisfaction and cost of operations thereby accommodating the interests of the passenger and the operator who are the two main stakeholders in the commercial aviation industry.展开更多
Tetraethyl orthosilicate (TEOS) and trimethyl orthosilicate (TMOS) alkoxysilanes are expensive common precursors for silicate based solgel derived bioactive glasses. Facile approa- ches involving low cost substitutes ...Tetraethyl orthosilicate (TEOS) and trimethyl orthosilicate (TMOS) alkoxysilanes are expensive common precursors for silicate based solgel derived bioactive glasses. Facile approa- ches involving low cost substitutes are a necessity for bioactive glass implants in bone regeneration therapy. Quaternary SiO2–Na2O–CaO– P2O5 bioactive glass was prepared by the solgel method from locally sourced sand as precursor. The monolith glass material obtained was subjected to immersion studies in simulated body fluid (SBF) for 21 days. The surface morphology and composition of the glass before and after immersion in SBF was studied using SEM-EDX, while pH analysis was used to monitor changes on the glass surface in SBF solution. FTIR was used to confirm apatite formation on the material. Results showed that the concentration of Ca, P and C increased on the surface of the glass sample as immersion time increased, which was attributed to the formation of carbonated hydroxyapatite (HCA). The material shows ability to bond to bone making it a promising scaffold material for bone repair.展开更多
Porous silica was synthesized via the sol-gel process using clay obtained locally from Ijero-Ekiti in Ekiti State, Nigeria and compared with silica synthesized under similar conditions from sodium metasilicate (Na2SiO...Porous silica was synthesized via the sol-gel process using clay obtained locally from Ijero-Ekiti in Ekiti State, Nigeria and compared with silica synthesized under similar conditions from sodium metasilicate (Na2SiO3) obtained comer- cially. The clay was initially refluxed with sodium hydroxide (NaOH) for 2 hours to extract SiO2 to form Na2SiO3, which was subsequently hydrolyzed to form a gel. The gel obtained was washed with deionized water to get rid of im-purities, dried and calcined at 800°C for 3 hours. The obtained silica powders were characterized using atomic absorp-tion spectrophotometer, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results showed that the vibrational modes and diffraction patterns of the silica derived from com-mercial Na2SiO3 and that prepared from clay were similar containing pure amorphous SiO2. The morphology of the commercially obtained silica showed better arrangement of particles and exhibited slightly lesser porosity (62.4%) compared to that derived from clay which had a porosity of 65.5%. The result indicates that clay has a potential for use as an environmentally safe and economic starting material for preparing porous silica instead of high quality precursors.展开更多
文摘Objective:To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation,changes in catalase activities and hepatic biochemical marker levels in blood plasma.Methods:Oxidative stress was induced by oral administration of ethanol(20%w/v) at a dosage of 5 niL/kg bw in rats.After 28 days of treatment,the rats were fasted overnight and sacrificed by cervical dislocation.Blood was collected with a 2 mL syringe by cardiac puncture and was centrifuged at 3000 rpm for 10 min.The plasma was analyzed to evaluate malondialdehyde(MDA),catalase activity,aspartate aminotransferase(AST),alkaline phosphatase(ALP) and alanine aminotransferase(ALT) concentrations.Results:Administration of alcohol caused a drastic increase(87.74%) in MDA level compared with the control.Pineapple peel extract significantly reduced the MDA level by 60.16%at 2.S mL/kg bw.Rats fed alcohol only had the highest catalase activity,treatment with pineapple peel extract at 2.5 mL/kg bw however, reduced the activity.Increased AST,ALP and ALT activities were observed in rats fed alcohol only respectively,treatment with pineapple peel extract drastically reduced their activities. Conclusions:The positive modulation of lipid peroxidation,catalase activities as well as hepatic biomarker levels of blood plasma by the methanolic extract of pineapple peels under alcoholinduced oxidative stress is an indication of its protective ability in the management of alcoholinduced toxicity.
文摘The basic goal of accounting is to provide quality accounting information that will aid reliable decision-making. The quality level of this accounting information comes from the company＇s governance practices, thereby emphasizing the importance of corporate governance in companies. Recently, following the financial crises resulting in accounting scandals, attention has been moving towards internal audit function as an important factor in the structure of corporate governance. This paper therefore examined the extent of the relationship between internal audit function and the quality of accounting information of companies. The study adopted the survey research design. The research instrument employed was questionnaire which was administered to internal auditors of the ＂Big Four＂. Linear regression analysis was employed in the analysis of the data collected with the use of Statistical Packages for Social Sciences （SPSS）. The results revealed that there is a significant relationship between the internal audit characteristics and the quality of accounting information. It was recommended that in order to provide credibility to the financial statement, there should be a law in place mandating attachment of internal auditors report to the financial statement.
基金the University of Lagos, Nigeria, for providing the platform for the Tetfund Research Grant (CRC/ TETFUND/No.2011/2013) used for this research
文摘Theductility and hardness of AA6011/SiCp composites using NaCl, SnCl2, NH4Cl and PdCl2 as wetting reagents were investigated. SiCp was cleaned with the wetting reagents, and used as reinforcement in AA6011 alloy using the stir casting method. Ductility and hardness responses of the composites were measured using standard methods. Microstructural features were examined using scanning electron microscopy and the phases were determined with the help of an X-ray diffractometer. The results show that for all wetting agents, the increase in cleaning time leads to initial increase in ductility to a certain value, but a decrease afterwards with further increase in cleaning time. The best combination of hardness （BHN 57.88） and ductility （11.91%） was shown under conditions of 40 g/L SnCl2and cleaning time of 60 min. A minor formation of Al4C3was noted in diffraction patterns, indicating that the formation of deleterious precipitate was hindered by the cleaning process.
文摘The effect of commercial enzymes on quality of wort developed from replacement of malted barley (100%) with sorghum as adjunct 50%, 60%, 70%, and 80% was investigated for pH, colour, filteration rate, extract asin, dry extract, viscosity, total soluble nitrogen and free amino nitrogen. The wort pH (5.6 - 6.0) is relatively stable with no significant changes at all levels of replacements. The colour is lighter with increment in proportion of the sorghum as it appears as colour diluents. Wort filteration rate is reduced with the sorghum replacement and the wort produced tends to be turbid which affects the utilization of the wort. The total soluble nitrogen and free amino nitrogen value increased with the use of commercial enzymes while the viscosity decreases with enzymes. The use of ceremix and cereflo have been found to be relatively more effective in the preparation of beer wort as observed for the result obtained in proportions of sorghum and malt barley. The use of high percentage sorghum as adjunct with commercial enzymes are found to be useful in production of high quality wort with low cost and profitability.
文摘<span style="line-height:1.5;"><span style="font-family:Verdana;">An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antioxidant systems possessed by living or</span><span style="font-family:Verdana;">g</span><span style="font-family:Verdana;">anisms are generally not enough to prevent them from oxidati</span><span style="font-family:Verdana;">ve damage</span><span style="font-family:Verdana;">s and the use</span></span><span style="line-height:1.5;font-family:Verdana;">s</span><span style="line-height:1.5;font-family:Verdana;"> of synthetic antioxidants also ha</span><span style="line-height:1.5;font-family:Verdana;">ve</span><span style="line-height:1.5;font-family:Verdana;"> some harmful effects. T</span><span style="line-height:1.5;"><span style="font-family:Verdana;">his study was aimed at evaluating the antioxidant activities of exopolysaccharides p</span><span style="font-family:Verdana;">roduced by lactic acid bacteria isolated from yoghurt. Lactic acid bac</span><span style="font-family:Verdana;">teria (LAB) were isolated from six different brands of commercially available yoghurt using deMan Rogosa Sharpe (MRS) agar. The LAB isolates were identified based on morphological and biochemical analyses and were screened for exopolysaccharide (EPS) production. The LAB isolates screened positive were used for EPS production in a liquid medium and the EPS produced were purified and quantified using standard methods. Antioxidant activities of the E</span><span style="font-family:Verdana;">PS were evaluated by determining the 1,1-dip</span><span style="font-family:Verdana;">henyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric ion reducing power, and total phenolic contents. Data obtained were analysed using Analysis of Variance. Total lactic acid bacterial count obtained from the yoghurt samples ranged from 0 - 3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL with sample A (Fan Yoghurt) having the highest LAB count (3.9 × 10</span><sup><span style="font-family:Verdana;">4</span></sup><span style="font-family:Verdana;"> CFU/mL). The isolated LAB and their incidence rate were </span><i><span style="font-family:Verdana;">Lactobacillus plantarum </span></i><span style="font-family:Verdana;">(25.49%),</span><i><span style="font-family:Verdana;"> L. delbrueckii </span></i><span style="font-family:Verdana;">(19.61%),</span><i><span style="font-family:Verdana;"> L. fermentum </span></i><span style="font-family:Verdana;">(15.69%),</span><i><span style="font-family:Verdana;"> L. acidophilus </span></i><span style="font-family:Verdana;">(13.73%), </span><i><span style="font-family:Verdana;">Leuconostoc mesenteroides </span></i><span style="font-family:Verdana;">(11.76%),</span><i><span style="font-family:Verdana;"> Lactococcus lactis </span></i><span style="font-family:Verdana;">(7.84%), and </span><i><span style="font-family:Verdana;">Lactobacillus casei </span></i><span style="font-family:Verdana;">(5.88%). Fifty-one out of the 64 LAB isolates were screened positive for EPS production and only six were able to produce substantial quantity of EPS ranging from 127.4 - 208.5 mg/L. The exopolysaccharides produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> had the highest DPPH radical scavenging activity (62.90%) while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (23.10%) at a concentration of 1000 μg/mL. Also, the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum</span></i><span style="font-family:Verdana;"> recorded the highest ferric ion reducing power (12.89 mg AAE/mL) at 1000 μg/mL while that of </span><i><span style="font-family:Verdana;">L. plantarum</span></i><span style="font-family:Verdana;"> had the lowest (5.62 mg AAE/mL). At 1000 μg/mL, the total phenolic contents of the EPS samples ranged from 1.41 - 1.58 mg GAE/mL, and the EPS produced by </span><i><span style="font-family:Verdana;">L. fermentum </span></i><span style="font-family:Verdana;">had the highest (1.58 mg GAE/mL) while those produced by </span><i><span style="font-family:Verdana;">L. paracasei </span></i><span style="font-family:Verdana;">had the lowest (1.41 mg GAE/mL). This study revealed that the exopolysaccharides produced by the LAB isolates showed high antioxidant activities with respect to their DPPH free radical scavenging activity, ferric ion reducing power and total phenolic contents.
文摘<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococcus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> is reported severally to be resistant to the drugs often used empirically for treatment of urinary tract infections (UTIs). Their ability to exhibit resistance to multiple drugs is a great de</span><span style="font-family:Verdana;">al of threat to successes recorded in the management of UTIs cause</span><span style="font-family:Verdana;">d by this pathogen. Lactic acid bacteria (LAB) have been demonstrated to exhibit an</span><span style="font-family:Verdana;">timicrobial activities but studies about their prospect against multi</span><span style="font-family:Verdana;">-drug resistant </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> are quite few. This study therefore investigated acti</span><span><span style="font-family:Verdana;">vities of LAB against the multi-drug resistant </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> recover</span></span><span style="font-family:Verdana;">ed fro</span><span style="font-family:Verdana;">m urine samples of symptomatic women. The three differ</span><span style="font-family:Verdana;">ent species of LAB </span><span><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 62, </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 86 and </span><i><span style="font-family:Verdana;">Weis</span></i></span><i><span style="font-family:Verdana;">sella</span></i><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> BTA 40) previously isolated and identified by 16S rRNA s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;">quencing were selected based on their history of antimicrobial activities. Their</span><span style="font-family:Verdana;"> m</span><span style="font-family:Verdana;">etabolites were employed in the antagonistic assays against six (6) mu</span><span style="font-family:Verdana;">lti-drug resista</span><span style="font-family:Verdana;">nt test pathogens recovered fro</span><span style="font-family:Verdana;">m urine samples of symptomatic, non-pregnant women attending clinics in Lagos, Nigeria and the control (</span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> subs bovis strain DSM 18669) following standard procedures. </span><span style="font-family:Verdana;">The pathogens showed resistances to almost all the antibiotics except</span><span style="font-family:Verdana;"> levofloxaci</span><span style="font-family:Verdana;">n, ciprofloxacin, imipenem while the control showed resistance to thr</span><span style="font-family:Verdana;">ee. The LAB, </span><i><span style="font-family:Verdana;">L.</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> inhibited five (83.3%) of the pathogens with zone diameter of 12 - 17 mm, followed by </span><i><span style="font-family:Verdana;">W</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> inhibiting three (50%) with 15 - 17 mm. </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> on the other hand, inhibited a pathogen and the control with zones of 13 mm and 14 mm respectively. In conclusion, the extracted metabolites of LAB inhibited the growth of multi-drug resistant clinical isolates of uropathogenic </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> and may therefore be potent alternatives to antibiotics.</span></span>
文摘In this study, Natural Raw Kaolinite (NRK) clay was used as an adsorbent for the investigation of the adsorption kinetics, isotherms and thermodynamic parameters of a cationic dye Safranine-O, also known as Basic Red 2 (BR2) from aqueous solution. The effects of pH, temperature, initial dye concentration and contact time on the adsorption capacity were evaluated and the adsorbent was characterized by XRD, BET and FTIR. The pseudo-first-order, pseudo-second-order kinetic models and the intraparticle diffusion model were used to describe the kinetic data and the rate constants were evaluated. The experimental data fitted very well with the pseudo-second-order kinetic model and also followed intraparticle diffusion model revealing that diffusion is not only the rate-controlling step. The Langmuir Freundlich and Dubinin-Radushkevic adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were also determined. The Langmuir model agrees with experimental data well. The activation energy, change of Gibbs free energy, enthalpy and entropy of adsorption were also evaluated for the adsorption of BR2 onto NRK.
基金supported by a Deutscher Akademischer Austausch Dienst (DAAD) Research Fellowship as well as a Staff Training Grant from Bells University of Technology, Ota, Nigeria
文摘Objective: To characterize the genetic diversity of Plasmodium falciparum ( P. falciparum ) field isolates in children from Lafia, North-central Nigeria, using the highly polymorphic P. falciparum merozoite surface protein 2 (MSP-2) gene as molecular marker. Methods: Three hundred and twenty children were enrolled into the study between 2005 and 2006. These included 140 children who presented with uncomplicated malaria at the Dalhatu Araf Specialist Hospital, Lafia and another 180 children from the study area with asymptomatic infection. DNA was extracted from blood spot on filter paper and MSP-2 genes were genotyped using allele-specific nested PCR in order to analyze the genetic diversity of parasite isolates. Results: A total of 31 and 34 distinct MSP-2 alleles were identified in the asymptomatic and uncomplicated malaria groups respectively. No difference was found between the multiplicity of infection in the asymptomatic group and that of the uncomplicated malaria group ( P >0.05). However, isolates of the FC27 allele type were dominant in the asymptomatic group whereas isolates of the 3D7 allele type were dominant in the uncomplicated malaria group. Conclusions: This study showed a high genetic diversity of P. falciparum isolates in North-central Nigeria and is comparable to reports from similar areas with high malaria transmission intensity.
文摘Objective:To investigate the ability of the methanolic extract of pineapple peel to attenuate alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues. Methods:Oxidative stress was induced by oral administration of ethanol(20%w/v) at a dosage of 5 mL/kg bw in rats.After 28 days of treatment,the rats were fasted overnight and sacrificed by cervical dislocation.Brain tissues were assayed for total phospholipid(TP) content and malondialdehyde(MDA).Results:Administration of alcohol significantly caused a reduction in TP content.Treatment with pineapple peel extract significantly increased the TP content. Significant high levels of MDA was observed in alcohol-fed rats,treatment with pineapple peel extract significantly reduced the MDA levels.Conclusions:Results obtained from this study indicates that pineapple peel extract protects against alcohol-induced changes in total phospholipids and lipid peroxidation in brain tissues.
文摘The occurrence of earthquakes in oceanic tren- ches can pose a tsunami threat to lives and properties in active seismic zones. Therefore, the knowledge of focal depth, magnitude, and time distribution of earthquakes along the trenches is needed to investigate the future occurrence of earthquakes in the zones. The oceanic trenches studied, were located from the seismicity map on： latitude ＋51 ° to＋53° and longitude -160° to 176° （Aleutian Trench）, latitude ＋40° to ＋53° and longitude ＋148° to＋165° （Japan Trench）, and latitude -75° to -64° and longitude -15° to ＋30° （Peru-Chile Trench）. The following features of seis- mic events were considered： magnitude distribution, focal depth distribution, and time distribution of earthquake. The results obtained in each trench revealed that the earthquakes increased with time in all the regions. This implies that the lithospheric layer is becoming more unstable. Thus, tectonic stress accumulation is increasing with time. The rate of increase in earthquakes at the Peru-Chile Trench is higher than that of the Japan Trench and the Aleutian Trench. This implies that the convergence of lithospheric plates is higher in the Peru-Chile Trench. Deep earthquakes were observed across all the trenches. The shallow earthquakes were more prominent than intermediate and deep earthquakes in all thetrenches. The seismic events in the trenches are mostly of magnitude range 3.0-4.9. This magnitude range may indi- cate the genesis of mild to moderate tsunamis in the trench zone in near future once sufficient slip would occur with displacement of water column.
文摘Carbide precipitates in Thin Wall Ductile Iron (TWDI) used for automotive applications needs to be eliminated or reduced for improved strength, ductility, crack propagation resistance and good machinability. Ductile iron thin section profiles (≤3 mm) present danger of massive carbide precipitations in the as-cast sample. Precipitated carbide phase is brittle and negatively affects the mechanical properties of the iron matrix. The suppression of carbide formation is associated with the nucleating properties of the nodularizer and innoculant alloys. This treatment is vital in ensuring that carbide precipitation, flake graphite structure and non-nodular graphite phases are reduced or completely eliminated in the TWDI castings. Therefore, the temperature and technique of treatment would influence the yield of the process, and ultimately the mechanical properties. In this study, the effect of nodularization and inoculation treatment temperature on the microstructure and mechanical properties of TWDI castings is examined. The results indicate that good nodularity and nodule count with better percent elongations are achieved using low treatment temperatures in descending order of 1490°C, 1470°C and 1450°C, but have negative effect at lower treatment temperature of 1430°C. However, TWDI castings have superior properties in terms of nodule counts and nodularity at 1450°C. Treatment temperature does not produce significant influence on ultimate tensile strength (UTS) and hardness of TWDI castings. TWDI castings show poor nodularity, nodule count and ductility at higher inoculation treatment temperatures of 1550°C, 1530°C and 1510°C.
文摘Previous genetic studies in cowpea [Vigna unguiculata (L.) Walp] have shown that an active bipartite transposable element (TE) is responsible for a range of mutant phenotypes of its leaf, stem and flower. Since type II TEs have not been characterized at the molecular level in cowpea, this study was initiated to survey the presence of type II TEs in the cowpea genome. Type II TEs: Enhancer/Suppressor-mutator (En/Spm) and Miniature Inverted-repeat Transposable Elements (MITEs) were isolated and characterized. The sequence identity between the EnSpm TE clones was 46% at the nucleotide level (NL) and 30% at the amino acid level (AL) while that of MITEs was 71% at NL and 63% at AL. These cowpea En/Spm TEs were 80% homologous with En/Spm elements of other crops at NL and 46% at AL. The MITEs were 96% similar at NL and 18% homologous at AL. DNA gel blot analysis confirmed the presence of the En/Spm TEs in cowpea. RT-PCR (reverse transcriptase polymerase chain reaction) analysis showed that the VuEnSpm-3 and the MITE clone, VuPIF-1 were actively transcribed in wild type and mutant cowpea tissues. Overall, our data show that multiple, divergent lineages of En/Spm and MITEs are present in the cowpea genome, some of which are actively transcribed. Our findings also offer new molecular resource to further investigate the genetic determinants underlying previously described mutant cowpea phenotypes.
文摘Nigeria is an agglomeration of different ethnic nationalities with multiplicity of religious inclination where Christianity and Islam are the dominant.The high level of intra and inter-ethnic rivalry between ethnic nationalities and extreme religious intolerance has resulted in many catastrophic clashes.These clashes have unquantifiable debilitating effects on the equilibrium of housing supply and delivery.The paper through deductive approach from literature review,and descriptive analysis,examined the various ethno-religious violence from post-independence Nigeria and its implications on the housing sector.Findings revealed that the importance of houses in African settings is beyond mere shelter,but are sacred and generational assets worth bequeathing.This underscores the reason it becomes target for attacks during ethno-religious violence.Deductive inferences made,indicated that the greater the severity of the violence on houses the more the number of IDPs(internally-displaced-persons),and this not healthy for a sustainable urban housing growth.
文摘The nutritional, microbiological and sensory characteristics of improved kunu-zaki produced from malted cereals enriched with malted soymilk at different substitution levels (0% - 30%) were investigated. Enrichment with soymilk and malting increased the protein, amino acid, ash and moisture content of the improved kunu-zaki. Malting resulted in a decrease in carbohydrate and fat content. The protein content of the malted samples ranged between 2.79% and 3.82% while that of unmalted was 2.36%. There was decrease in the concentration of phytic acid and trypsin inhibitor after malting but the concentration increased as soymilk was added. Microbiological analyses showed that microbial load of samples increased with the addition of soymilk. There was a significant difference (p 0.05) in the sensory attributes, acceptability decrease with increase in soymilk addition because of the beany flavor.
文摘The challenges facing public schools are multifaceted and include: teachers dissatisfaction, non-commitment of educators, chronic absenteeism by educators, low morale, poor work ethics by educators, late coming of both educators and learners, overcrowding in classes, lack of technical resources and many more. A cursory investigation of public secondary school buildings in Ado-Odo/Ota L.G.A shows its deplorable conditions of structural, aesthetical and decorative disrepair. Therefore the paper focused on examining users “perception of the present deplorable physical condition and neglect of public secondary school. The study engaged the use of quantitative method of analysis, employing the use of questionnaire administered randomly and distributed face-to-face to targeted despondences”. The result of findings revealed performance/productivity of building users depends largely on working and learning condition of building. The outcomes of the research would help policy makers, facilities maintenance experts and professionals alike to device a policy for regular maintenance of public building in other to enhance performance and increase productivity amongst users.
文摘The increasing demand for airline services amidst limited resources results in passenger dissatisfaction and dwindling revenue for airports and airlines. The dynamics of service demand and resource supply results in check-in issues for the stakeholders in the commercial aviation industry. This has the effect of impacting negatively on service performance, cost of operations, customer satisfaction, and overall throughput. Hence, this paper modelled the travelers’ check-in process at the “D Wing” of the Departure Section of Murtala Muhammed International Airport (MMIA), Ikeja, using Arena Software Tool. The work was carried out by determining the parameters of the queues at designated service points in the check-in process. The primary data required to develop the model were acquired by direct observation of passenger flow and oral interview. Thus, the average check-in time was determined. Thereafter, a model of the international check-in system of the MMIA was developed using Arena software in combination with Microsoft Office tools. The data collected were therefore inputted into the model and simulated;the real result was compared with the simulation result of 133 completions and there was no significant difference. The result showed that the model is a representation of the real system under study. Further work will be tailored towards simulation (<em>i.e</em>. the model will be subjected to experimentation in order to have different scenario).
文摘With the current situation of insecurity in Nigeria and the worsening condition of Nigerian roads, there is increasing demand for air travel. This increasing demand for airline services amidst limited resources results in passenger dissatisfaction and reduction of revenue for airports and airlines. The dynamics of service demand and resource supply result in check-in issues for all the stakeholders in the commercial aviation industry. Hence, this research simulated the developed model for travelers’ check-in process at the “D Wing” of the Departure Section of Murtala Muhammed International Airport (MMIA), Ikeja, using Arena Software Tool. The simulation of the developed model was carried out by varying five different configurations of the servers with respect to the baggage weighing machines and passenger profiling devices to obtain the minimum average check-in time (ACT) for the process, with each configuration undergoing 133 completions of simulation runs. The result of the experimentation revealed that the 3 × 3 × 4 configuration of servers produced the smallest ACT of 18.25 minutes. This translates to a difference of about 58 minutes from the 76.16 minutes ACT of the real system;representing about 76% improvement in the check-in time of passengers. This study contributed to knowledge by revealing that the main choke points in the MMIA check-in system occur at the baggage weighing and passenger profiling areas as against the check-in counter sub-section as advanced by previous works. Furthermore, the research added value to knowledge by creating a balance between customer satisfaction and cost of operations thereby accommodating the interests of the passenger and the operator who are the two main stakeholders in the commercial aviation industry.
文摘Tetraethyl orthosilicate (TEOS) and trimethyl orthosilicate (TMOS) alkoxysilanes are expensive common precursors for silicate based solgel derived bioactive glasses. Facile approa- ches involving low cost substitutes are a necessity for bioactive glass implants in bone regeneration therapy. Quaternary SiO2–Na2O–CaO– P2O5 bioactive glass was prepared by the solgel method from locally sourced sand as precursor. The monolith glass material obtained was subjected to immersion studies in simulated body fluid (SBF) for 21 days. The surface morphology and composition of the glass before and after immersion in SBF was studied using SEM-EDX, while pH analysis was used to monitor changes on the glass surface in SBF solution. FTIR was used to confirm apatite formation on the material. Results showed that the concentration of Ca, P and C increased on the surface of the glass sample as immersion time increased, which was attributed to the formation of carbonated hydroxyapatite (HCA). The material shows ability to bond to bone making it a promising scaffold material for bone repair.
文摘Porous silica was synthesized via the sol-gel process using clay obtained locally from Ijero-Ekiti in Ekiti State, Nigeria and compared with silica synthesized under similar conditions from sodium metasilicate (Na2SiO3) obtained comer- cially. The clay was initially refluxed with sodium hydroxide (NaOH) for 2 hours to extract SiO2 to form Na2SiO3, which was subsequently hydrolyzed to form a gel. The gel obtained was washed with deionized water to get rid of im-purities, dried and calcined at 800°C for 3 hours. The obtained silica powders were characterized using atomic absorp-tion spectrophotometer, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results showed that the vibrational modes and diffraction patterns of the silica derived from com-mercial Na2SiO3 and that prepared from clay were similar containing pure amorphous SiO2. The morphology of the commercially obtained silica showed better arrangement of particles and exhibited slightly lesser porosity (62.4%) compared to that derived from clay which had a porosity of 65.5%. The result indicates that clay has a potential for use as an environmentally safe and economic starting material for preparing porous silica instead of high quality precursors.
