3,048 research outputs found

    Factors affecting the performance of small-scale construction firms in Nigeria

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    Small-Scale Construction Firms (SSCFs) in Nigeria are confronted with several problems that tend to limits their contributions to the country’s GDP, employment generation as well as infrastructural development. Although the prospect for improved contribution towards development still exists, there is the need for implementation of good management practices and support measures. Therefore, this study uses focus group to explore factors affecting the performance of small-scale construction firms and possible remedial measures. The study identified 113 factors that negatively affect performance. The interview further helped in grouping the variables into seven (7) groups. The focus group participants helped to identify and classify eighty-two (82) measures into internal and external measures. Internal measures are to be implemented by the construction firms towards solving internal constraints and external measures to be implemented by government and other stakeholders towards minimizing problems that are outside the control of the small-scale construction firms. Results revealed critical factors affecting performance such as financial indiscipline by contractors, lack of experience and track records, poor policy by commercial banks on SMEs, corruption, effects of globalisation, multiple taxation, stringent prequalification criteria, poor design and specifications, lack of entrepreneurship skills and delay in payment for work done. The study recommends the implementation of remedial measures by management of small-scale construction firms and governments with other stakeholders that could improve performance. Keywords: small-scale constructions firms, focus group, problems, remedial measures and performance.&nbsp

    Stability Study of Some Selected Nigerian Crude Oil Emulsions and the Effectiveness of Locally Produced Demulsifier

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    Crude oil emulsion stability causes high viscosity of crude oil which leads to problems in pipeline transportation and processing. In this research, four samples of crude oil emulsions were collected from Ughelli East Wellhead and labeled A, B, C and D. These samples were characterized to determine their specific gravity, 0API gravity, structural composition, density, temperature, amount of water, amount of gas and the gross crude oil production. The 0API at 60 0F showed that all the samples had values below 30 0API which was an indication that the crude oil produced from these wells were heavy crude oil. The FTIR spectra showed bands at 3444.55 cm-1 for Sample A, 3418.23 cm-1 and 3175.94 cm-1for Sample B, 3444.61 cm-1 for Sample C and  3444.49 cm-1 for Sample D attributing to strong and broad O-H stretch, H-bonded and an indication of Asphaltenes presence; the alkanes signal, C-H stretch at 2961.14 cm-1 for Sample A, 2926.00 cm-1 for Sample B, 2924.15 cm-1 for Sample C and 2922.88 cm-1 for Sample D are indications of the presence of wax; C=O stretch at 1737.74 cm-1 only present in sample C is an indication of the presence of resins. The well test details showed that sample A and B had smaller water percentage in the gross crude oil production than Sample C and D with high water percentage. Therefore crude oil produced from these four wells represented by samples A, B, C and D contains natural emulsion stabilizers and stable. However, the stability of Samples A and B are more than that of Samples C and D. The performance of locally produced demulsifier increased with increase in residence time of contacting it with the emulsion samples at their operating temperatures, while equal dosage of patent Separol N46 demulsifier showed no performance within thesame residence time. However, treatments AWHT, BRT, CWHT and DWHT all at well head temperatures of 35.6 0C, 27 0C, 48.2 0C and 48.8 0C respectively showed that most water was expelled in 480 minutes. Key words: Stability, Selected, Crude oil, Emulsion, Demulsifiers, Treatmen

    Isolation and characterisation of microorganisms contaminating herbal infusion sold in Minna, Nigeria

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    The microbiological assessment of ten herbal infusion samples from ten different locations in Minna, Niger State was investigated. The assessment of the microbial contamination on the herbal products was carried out, using standard methods. Pour plate method was used to cultivate serially diluted portions of the medicinal plant infusion samples. The results revealed that all the herbal preparations had the presence of microbial contaminants. The total heterotrophic counts of the different herbal samples ranged from 0 cfu/mL to 25.0 × 108cfu/mL while the total fungal counts ranged from 3.0×106cfu/mL to 3.5×108cfu/mL. The total viable bacteria counts showed that the highest counts of 25.0 × 108cfu/mL was recorded in the sample from Bosso and the least counts of 0 cfu/mL from Kasuwan-Gwari while the total fungal counts showed that the highest count of 3.5×108cfu/mL was found in the sample obtained from FUT campus and the least counts of 3.0×106cfu/mL in the sample from Mai-Kunkele. One way analysis of variance (ANOVA) showed that there was significant difference (p<0.05) in the microbial load of the herbal infusions from each location. The microbial isolates identified were E. coli, Staphylococcus aureus, Shigella sp, Klebsiella sp, Pseudomonas sp, Micrococcus sp, Salmonella sp, Aspergillus sp, Penicillium sp and Saccharomyces cerevisaie. Members of the genus Aspergillus were found to be predominant. This suggests that the herbal infusion harbors microorganisms that could be hazardous to human health and hence producers should maintain the highest possible level of hygiene during the processing and packaging of the products in order to ensure safety of the products

    Dietary Supplementation with Different ω-6 to ω-3 Fatty Acid Ratios Affects the Sustainability of Performance, Egg Quality, Fatty Acid Profile, Immunity and Egg Health Indices of Laying Hens

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    The supplementation of different ω-6/ω-3 ratio to the diets of the laying hens has been studied to evaluate the effects on performance, egg quality, egg health indices, egg fatty acid profiles, and immune response. One-hundred and twenty, 50-weeks-old hens were divided into three groups fed diets with different ω-6/ω-3 polyunsaturated fatty acids (PUFA) at ratio: 16.7:1, 9.3:1, and 5.5:1, respectively. Each group contained eight replicates of five hens. Hens fed the diet with the highest ω-6/ω-3 ratio had significantly increased weight gain compared to those fed the 5.5:1 and 9.3:1 ω-6/ω-3 ratios. In contrast, hens fed the 9.3:1 ω-6/ω-3 ratios laid significantly more eggs, had increased egg mass, greater livability, and a better FCR than the control group. However, hens fed a ratio of 5.5:1 ω-6/ω-3 PUFA showed improved thrombogenic, atherogenic, hypocholesteremia, and hypocholesteremia/hypercholesteremia indices. In conclusion, laying hens of the 9.3:1 ω-6/ω-3 PUFA group showed improved laying performance, while a ratio of 5.5:1 enriched the ω-3 PUFA in eggs and boosted the immune response of hens

    Impact of germination on the techno‐functional properties, nutritional composition, and health‐promoting compounds of brown rice and its products:a review

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    Rice is a popular grain and forms part of the daily diet of people throughout the world. However, the consumption of rice and its products is sometimes limited by its high glycemic index due to its high starch content, low protein content and quality, and low bioavailability of minerals due to the presence of anti‐nutritional factors. This has partly stimulated research interest in recent times toward the use of bioprocessing techniques such as germination as cheap and natural means to improve the nutritional quality, digestibility, and health properties of cereals, including rice, to partially achieve nutrition and food security in the developing regions of the world. This review highlights the impact of germination on the nutritional quality, health‐promoting properties, and techno‐functional characteristics of germinated brown rice grains and their products. The review demonstrated that germinated rice grains and their products have improved nutritional quality and digestibility, modified functional properties, and showed antioxidant, anti‐inflammatory, anti‐diabetic, anti‐obesity, anti‐cancer, and anti‐cardiovascular activities. Germination appears to be a suitable bioprocessing method to improve the nutritional quality and bioactive constituents and modify the techno‐functional properties of rice grains for diverse food applications and improved global nutrition and food safety

    Policies for care during the third stage of labour: a survey of maternity units in Syria

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    <p>Abstract</p> <p>Background</p> <p>Care for women during the third stage aims to reduce the risk of major haemorrhage, but is very variable. The current World Health Organisation (WHO) recommendation is that care should include administration of a uterotonic (oxytocin, if it is available) soon after birth of the baby, delayed cord clamping, and delivery of the placenta by controlled cord traction.</p> <p>Methods</p> <p>To ascertain care policies used during the third stage of labour in maternity units in Syria, we conducted a survey of 69 maternity units in obstetric and general public hospitals. A brief questionnaire was administered by face to face interview or telephone with senior obstetricians and midwives. Outcome measures were the use of prophylactic uterotonic drugs, timing of cord clamping, use of controlled cord traction, and treatment for postpartum haemorrhage. Obstetricians were asked about both vaginal and caesarean births, midwives only about vaginal births.</p> <p>Results</p> <p>Responses were obtained for 66 (96%) hospitals: a midwife and an obstetrician were interviewed in 40; an obstetrician only in 20; a midwife only in 6. Responses were similar, although midwives were more likely to report that the umbilical cord was clamped after 1-3 minutes or after cessation of pulsation (2/40 obstetricians and 9/40 midwives). Responses have therefore been combined.</p> <p>One hospital reported never using a prophylactic uterotonic drug. The uterotonic was Syntometrine<sup>® </sup>(oxytocin and ergometrine) in two thirds of hospitals; given after delivery of the placenta in 60 (91%) for vaginal births, and in 47 (78%) for caesarean births. Cord clamping was within 20 seconds at 42 hospitals 64%) for vaginal births and 45 (75%) for caesarean births. Controlled cord traction was never used in a quarter (17/66) of hospitals for vaginal births and a half (32/60) for caesarean births.</p> <p>68% of respondents (45/66) thought there was a need for more randomised trials of interventions during the third stage of labour.</p> <p>Conclusion</p> <p>Most maternity units report using Syntometrine<sup>®</sup>, usually given after delivery of the placenta, clamping the cord within 20 seconds, and using controlled cord traction.</p

    Combined search for the quarks of a sequential fourth generation

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    Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO

    Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

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    A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

    Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

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    The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO
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