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Antimethicilin resistance agents from marine actinomycetes from soil sediments of Lagos Lagoon

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Journal of Coastal Life Medicine 2015年第3期 193-198页

作者： davies olabisi flora Adeleye Isaac Adeyemi Wang Peng George Department of Microbiology University of LagosAkokaLagos StateNigeria Department of Chemistry Georgia State UniversityAtlantaGeorgiaUSA

Objective:To evaluate the isolation of actinomycetes strains with potential for producing antimicrobials with high methicilin resistance ***:The soil samples were collected from four different locations of Lagos *** Actinomycetes were isolated from the samples by serial dilution using spread plate *** were selected based on their cultural characteristics as well as their Gram reaction and phenotypically and molecularly characterized Streptomyces *** were inoculated in starch casein and Kuster’s broth media and secondary metabolites were screened for antimicrobial activity against the following microorganisms:methicillin resistant Staphylococcus aureus,Staphylococcus aureus ATCC 29213,Escherichia coli ATCC 29522,Pseudomonas aeruginosa ATCC 27853,Candida albicans,Enterococcus faecalis ATCC ***-negative staphylococci isolated from HIV patients were also used(Staphylococcus warneri,Staphylococcus xylosus and Staphylococcus epidermidis).The antimicrobial metabolites of the isolates were identified using gas chromatography-mass ***:Extracts from isolates ULS12 and ULS13 showed antimicrobial activity against methicillin resistant Staphylococcus aureus while ULK3 inhibited Candida albicans *** gas chromatography-mass spectrometer data analysis showed the antibiotic profile of these ***:The isolates ULS12 and ULS13 were found to display the highest antimicrobial activity against the test organisms and could be a potential source of new antibiotics.

关键词： Marine actinomycetes Streptomyces Antimethicillin resistance Molecular identification Morphological characteristics GC-MS

Himalomycin A and cycloheximide-producing marine actinomycete from Lagos Lagoon soil sediment

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Journal of Coastal Life Medicine 2015年第5期 361-365页

Objective:To isolate and screen Actinomycetes from Lagos Lagoon soil sediments for antibiotic ***:Soil samples were collected from four different locations of Lagos Lagoon and were dried for 2 *** were isolated by serial dilution using spread plate method on starch casein and Kuster’s agar supplemented with 80μg/mL cycloheximide to prevent fungal *** plates were incubated at 28°C for 1-2 *** were selected based on their cultural characteristics as well as their Gram’s reaction and subcultured on same media for isolation and incubated at 28°C for 3 *** cultures were maintained on nutrient agar slants at 4°***,they were inoculated into starch casein and Kuster’s broth media and incubated at 28°C for 8 *** resulting crude extracts were screened for antimicrobial activity against the following microorganisms:methicillin resistant Staphylococcus aureus,Staphylococcus aureus ATCC 29213,Escherichia coli ATCC 29522,Pseudomonas aeruginosa ATCC 27853,Candida albicans and Enterococcus faecalis ATCC ***-negative staphylococci isolated from HIV patients were also used(Staphylococcus warneri,Staphylococcus xylosus and Staphylococcus epidermidis).Extraction of secondary metabolites was carried out and analysed using gas chromatography-mass ***:All the isolates displayed varying antimicrobial activity against at least one of the test *** A was identified in the extract from isolate *** gas chromatography-mass spectrometer data analysis showed the antibiotic profile of these ***:The isolate ULS7 was found to display the highest antimicrobial activity against the test organisms.

关键词： Marine Actinomycetes Streptomyces Himalomycin A Cycloheximide Molecular identification Morphological characteristics Gaschromatography-mass spectrometer

Anticancer potential of metabolic compounds from marine actinomycetes isolated from Lagos Lagoon sediment

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Journal of Pharmaceutical Analysis 2019年第3期9卷 201-208页

作者： olabisi flora davies-Bolorunduro Isaac Adeyemi Adeleye Moshood Olushola Akinleye Peng George Wang Department of Microbiology University of Lagos Akoka Lagos Nigeria Department of Pharmaceutical Chemistry University of Lagos Idi-Araba Lagos Nigeria Department of Chemistry Georgia State University Atlanta GA United States

Thirty-two actinomycetes strains were isolated from sediment samples from 12 different sites at Lagos Lagoon and identified using standard physiological and biochemical procedures as well as 16S rDNA gene sequence analysis. Secondary metabolites were extracted from the strains and their anticancer activity on the K562 (Human acute myelocytic leukemia), HeLa (cervical carcinoma), AGS (Human gastric), MCF- 7 (breast adenocarcinoma) and HL-60 (Human acute promyelocytic leukemia) cell lines was determined. The metabolic extracts exhibited cytotoxicity with IC50 values ranging from 0.030 mg/mL to 4.4 mg/mL. The Streptomyces bingchenggensis ULS14 extract was cytotoxic against all the cell lines tested. The bioactivity-guided extraction and purification of the metabolic extracts from this strain yielded two purified anticancer compounds: ULDF4 and ULDF5. The structures of the extracted compounds were determined using spectroscopic analyses, including electrospray ionization mass spectrophotometer and nuclear magnetic resonance (1 Dimensional and 2 Dimensional), and were shown to be structurally similar to staurosporine and kigamicin. The IC50 of ULDF4 and ULDF5 against the HeLa cell line was 0.034 mg/mL and 0.075 mg/mL, respectively. This study is the first to reveal the anticancer potential of actinomycetes from Lagos Lagoon, which could be exploited for therapeutic purposes.

关键词： Streptomyces bingchenggensis ULS14 Metabolic extracts Cytotoxicity Spectroscopy Kigamicin Staurosporine

A synergistic effect of zinc oxide nanoparticles and polyethylene butene improving the rheology of waxy crude oil

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Petroleum Research 2023年第2期8卷 217-225页

作者： Toyin olabisi Odutola University of Port Harcourt Nigeria

This research examined the use of 75 nm zinc oxide nanoparticles(nano ZnO)and polyethylene butene(PEB)to decrease the viscosity of Nigerian waxy crude *** rheology of the crude oil was assessed by measuring the viscosity and shear stress of samples containing PEB at 500,1000,2000,3000,4000 or 5000 ppm and nano ZnO at 1,2,3 or 4 wt% between 10 and 35℃ at shear rates from 1.7 to 1020 s^(-1).Rheological modeling indicated that a power law pseudoplastic model was the best fit for the experimental data,giving a regression coefficient of *** addition of these inhibitors induced Newtonian fluid behavior in the crude samples such that the shear stress-shear rate relationship plots were linear at all *** optimum concentrations of the inhibitors in this study were 2000 ppm PEB(providing a 33% viscosity reduction)and 1 wt% nano ZnO(providing a 26% viscosity reduction).A combination of these additives at these concentrations provided a synergistic effect and gave a greater viscosity reduction of 41%.This work demonstrates that a blend of ZnO nanoparticles and PEB can improve the flowability of waxy crude.

关键词： Flow assurance Wax prevention Zinc oxide nanoparticles Poly ethylene butene Niger Delta waxy crude

Occurrence of Multi-Drug Resistant <i>Listeria species</i>in Faecal Samples of Poultry Chickens in Rural Farms in Lagos State, Nigeria

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Advances in Infectious Diseases 2021年第1期11卷 49-59页

作者： Emelda E. Chukwu Veronica N. Ibeh olabisi F. davies-Bolorunduro Center for Infectious Diseases’ Research Microbiology Department Nigerian Institute of Medical Research Yaba Lagos State Nigeria National Agency for Food and Drug Administration and Control Lagos State Nigeria Center for Tuberculosis Research Microbiology Department Nigerian Institute of Medical Research Yaba Lagos State Nigeria

Background: Listeriosis is a common zoonotic disease caused by a foodborne pathogen, Listeria monocytogenes. Poultry meat and products have been established as vehicles of transmission of pathogenic Listeria strains to humans. This study evaluates the occurrence of Listeria species in faeces of poultry chicken in Lagos. Methods: One hundred and fourteen pooled fresh faecal samples from cage-reared broiler chickens were collected from 12 farms in three rural areas in Lagos State from May to August 2019. All samples were analysed for Listeria species detection according to ISO11290-1 standard and confirmed using PCR assay. Susceptibility testing was performed using the Kirby-Bauer disc diffusion technique. Results: Twenty-eight (24.6%) Listeria species were detected from 114 faecal samples. The isolated Listeria species were L. monocytogenes 8 (7.0%), L. ivanovii 9 (7.9%), L. grayi 7 (6.1%) and L. innocua 4 (3.5%). There was no significant difference in the frequency of occurrence of Listeria species across the different locations (X2 = 4.98, p = 0.08). The listeria species were susceptible to Augmentin (96.4%), vancomycin (85.7%) and co-trimoxazole (82.1%), but resistant to ceftazidime (100%), tetracycline (75.0%) and ciprofloxacin (71.4%). Conclusion: This study reveals high occurrence of multi-drug resistant Listeria species in faecal samples of poultry chickens in Lagos state which may be an important vector in the contamination of the environment and transmission of antibiotic resistant Listeria species to consumers.

关键词： Listeriosis Listeria monocytogenes Multi-Drug Resistance Poultry Farms Zoonotic Disease Chickens

Terminal-Modality-Based Joint Call Admission Control Algorithm for Fair Radio Resource Allocation in Heterogeneous Cellular Networks

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International Journal of Communications, Network and System Sciences 2012年第7期5卷 392-404页

作者： olabisi E. Falowo Department of Electrical Engineering University of Cape Town Cape Town South Africa

There is a problem of unfairness in allocation of radio resources among heterogeneous mobile terminals in heterogeneous wireless networks. Low-capability mobile terminals (such as single-mode terminals) suffer high call blocking probability whereas high-capability mobile terminals (such as quad-mode terminals) experience very low call blocking probability, in the same heterogeneous wireless network. This paper proposes a Terminal-Modality-Based Joint Call Admission Control (TJCAC) algorithm to reduce this problem of unfairness. The proposed TJCAC algorithm makes call admission decisions based on mobile terminal modality (capability), network load, and radio access technology (RAT) terminal support index. The objectives of the proposed TJCAC algorithm are to reduce call blocking/dropping probability, and ensure fairness in allocation of radio resources among heterogeneous mobile terminals in heterogeneous networks. An analytical model is developed to evaluate the performance of the proposed TJCAC scheme in terms of call blocking/dropping probability in a heterogeneous wireless network. The performance of the proposed TJCAC algorithm is compared with that of other JCAC algorithms. Results show that the proposed algorithm reduces call blocking/dropping probability in the networks, and ensure fairness in allocation of radio resources among heterogeneous terminals.

关键词： Call Admission Control Terminal Modality Heterogeneous Terminals Radio Access Technology Call Dropping Call Blocking Markov Chain Mobile Users

Fast Fourier Transform of Multi-Assets Options under Economic Recession Induced Uncertainties

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American Journal of Computational Mathematics 2019年第3期9卷 143-157页

作者： Philip Ajibola Bankole olabisi O. Ugbebor Department of Mathematics University of Ibadan Ibadan Nigeria

A Fast Fourier transform approach has been presented by Carr & Madan (2009) on a single underlying asset. In this current research paper, we present fast Fourier transform algorithm for the valuation of Multi-asset Options under Economic Recession Induced Uncertainties. The issue of multi-dimension in both finite and infinite case of Options is part of the focus of this research. The notion of economic recession was incorporated. An intuition behind the introduction of recession induced volatility uncertainty is revealed by huge volatility variation during the period of economic recession compared to the period of recession-free. Nigeria economic recession outbreak in 2016 and its effects on the uncertainty of the payoffs of Nigeria Stocks Exchange (NSE) among other investments was among the motivating factors for proposing economic recession induced volatility in options pricing. The application of the proposed Fast Fourier Transform algorithm in handling multi-assets options was shown. A new result on options pricing was achieved and capable of yielding efficient option prices during and out of recession. Numerical results were presented on assets in 3-dimensions as an illustration taking Black Scholes prices as a bench mark for method effectiveness comparison. The key findings of this research paper among other crucial contributions could be seen in computational procedure of options valuation in multi-dimensions and uncertainties in options payoffs under the exposure of economic recession.

关键词： Fast Fourier Transform (FFT) Multi-Assets Finite and Infinite Dimension of Assets Economic Recession Volatility Change European Options

Exploring Factors Influencing Recruitment and Retention of Nurses in Lagos State, Nigeria within Year 2008 and 2012

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Open Journal of Nursing 2014年第8期4卷 590-601页

作者： Modupe O. Oyetunde olabisi O. Ayeni Department of Nursing College of Medicine University of Ibadan Ibadan Nigeria Lagos State School of Nursing Lagos Nigeria

Objective: To explore the factors influencing recruitment and retention of nurses in Lagos State Hospitals. Background: Despite the perceived efforts made by Hospitals Management in Lagos State to recruit and retain nurses, there is still inadequate number of nurses to match the demand of care needed by patients in the hospitals. Methods: The descriptive study utilized mixed methods to gather data. It consisted of 330 consented and randomly selected nurses for the survey and 14 purposively selected nurse leaders and Director for the interview. The instruments were pretested questionnaire, semi-structured interview guide and existing records. Result: The study revealed that all health institutions in Lagos State were aware of the standard procedures of recruitment of nurses, but often engages in replacement rather than proper recruitment. Most of the Nursing leadership positions in Lagos State were vacant. More than half (68.2%) of the nurse respondents were not sure if they would still be working in their health institution in the next five years. It was revealed that the turnover rate of nurses in the State Health institutions was higher than the Federal health institutions in Nigeria. Conclusion: Increment in salary and allowances rated the best influence on recruitment and retention of nurses in Lagos State. Lack of nursing leadership;sense of job security and work environment were the major factors influencing recruitment and retention of nurses. There is need for adequate human resource planning;increased efforts and formulation of policies that will improve recruitment and retention of nurses in Lagos State of Nigeria.

关键词： Recruitment of Nurses Retention of Nurses Shortage of Nurses Nursing Leadership Nigeria

Socio-Economic Status and Gender as Determinant of Dietary Practices of Secondary School Students’by Exposure to Pictorial Nutrition Education for Sustainability

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Journal of Health Science 2019年第1期7卷 29-36页

作者： Isoken Ihensekhien olabisi Busari Caroline E Adedeji Lilian Imuetinyan Salami Department of Vocational and Technical Education Faculty of Education University of Benin Benin city 300213 Nigeria Department of Home Economics School of Vocational and Technical Education FCT Akoka Nigeria

Objectives:The study examined socio-economic status and gender as determinant of dietary practices of senior secondary school students in Edo South Senatorial district for healthy living and ***:Quasi experimental research design was employed in the *** research questions were raised and formulated into hypotheses,tested at 0.05 level of significance.A multistage random sampling technique was used to sample 245 students from two public schools in Oredo local government areas within Edo south senatorial ***(2)instruments(questionnaire and achievement test)validated and reliability of 0.64 and 0.84 reliability co-efficient were *** demographic data/SES,dietary practices(DDPSESQ)was used to obtain information on their dietary practices and socio-economic status,while the pictorial nutrition achievement test(PNAT)consisted of the pre-and *** treatment package comprised planned lessons of 40 minutes each for six(6)*** data collected were analyzed using inferential statistics;hypotheses 1 and 2 were tested using the independent t-test while hypothesis 3 was tested using One-Way ANOVA ***:The study revealed that there is no significant difference in dietary practices of students of high,medium and low socio-economic status as a result of exposure to pictorial nutrition *** was no significant difference in dietary practices by *** study concluded that socio-economic status does not determine dietary practices of secondary school students for responsible living.

关键词： Socio-economic status gender dietary practices adolescents and sustainability