检索结果-南通市图书馆

American Journal of Plant Sciences 2015年第9期6卷 1575-1580页

作者： ayodele adelusi oyedeji Joshua Kayode Lynn Besenyei Michael Augustine Fullen Faculty of Science and Engineering University of Wolverhampton Wolverhampton UK Department of Plant Science Faculty of Science Ekiti State University Ado-Ekiti Nigeria Department of Biological Sciences Niger Delta University Wilberforce Island Nigeria

The study investigates the germination of selected leguminous tree species (LTS) native to the forest ecosystem and oil producing areas of Nigeria. Germination experiments of 250 seeds from each of the selected members of the Fabaceae family: Bauhinia monandra (Kurz), Delonix regia (Boj. ex Hook.) Raf. and Tetrapleura tetraptera (Schum. & Thonn.) Taubert were conducted in petri dishes double-layered with Whatman No. 1 filter papers for 10 days and moistened with varying concentrations of crude oil contaminated soil water extracts (0, 25, 50, 75 and 100 ml), with a view to determining the ability of these plants to germinate and establish in soil polluted with crude oil. The mean percentage germination of each tree species was thus determined. All the LTS germinated, but germination was concentration dependent, as percentage germination decreased with increased oil concentrations. Evaluation of the initial growth responses and tolerances of these LTS in oil-polluted soil may provide useful information about the potential of these plant species for phytoremediation.

关键词： Germination Fabaceae Crude Oil Pollution Phytoremediation Tree Species

Adaptive and Predictive Control Strategies for Wind Turbine Systems: A Survey

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 364-378页

作者： Magdi S.Mahmoud Mojeed O.oyedeji the Systems Engineering Department King Fahd University of Petroleum and Minerals (KFUPM)

The wind turbine(WT) is a renewable energy conversion device for transformation of kinetic energy from the wind to mechanical energy for subsequent use in different *** paper focuses on wind turbine control design *** content is divided into the following parts: 1) An overview of the recent advances that have been made in the application of adaptive and model predictive control strategies for wind turbines. 2) Summarizes some important aspects of modeling of wind turbines for control studies. 3) Provides an outlook on the application of adaptive model predictive control for uncertain systems to stimulate new research interests for wind turbine systems. We provide an overall picture of the research results with evaluation of the merits/demerits.

关键词： Adaptive control model predictive control wind turbine(WT)

Anti-inflammatory activity of the essential oils of Cymbopogon validus(Stapf) Stapf ex Burtt Davy from Eastern Cape, South Africa

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2016年第5期9卷 415-419页

作者： Pamela Rungqu Opeoluwa oyedeji Benedicta Nkeh-Chungag Sandile Songca Oluwatobi Oluwafemi Adebola oyedeji Department of Chemistry Faculty of Science and Agriculture University of Fort Hare Department of Biological and Environmental Sciences Faculty of Natural Sciences Walter Sisulu University Department of Chemical and Physical Sciences Faculty of Natural Sciences Walter Sisulu University Department of Applied Chemistry Faculty of Sciences University of Johannesburg

Objective: To evaluate the essential oil composition and the anti-inflammatory activity of Cymbopogon validus(C. validus) leaves and flowers. Methods: A total of 300 g of fresh or dry(leaves and flowers) of C. validus were cut into small pieces and subjected to hydro-distillation method for approximately 5 h using the Clevenger apparatus. The extracted essential oils were then used for testing the anti-inflammatory activity. The anti-inflammatory activity was evaluated by using egg-albumin induced paw edema. Results: The extracted oils had the following yields 2.2% for fresh leaves, 2.0% for dry leaves and 2.4% v/w for dry flowers. GCMS results revealed that the oils contained artemisia ketone(37.5%), linalool(3.2%-29.6%), northujane(4.4%-16.8%), verbenone(13.5%), naphthalene(1.7%-9.6%), δ-cadinene(0.5%-8.1%), hedycaryol(5.4%-7.6%) and α-eudesmol(6.5%-6.7%) as the major constituents. C. validus essential oils showed significant(P<0.05) anti-inflammatory effects from the first 30 min after albumin injection compared to aspirin which had a later onset of effect. Conclusions: The findings of this study show that the essential oil extracted from C. validus fresh or dry leaves and flowers have anti-inflammatory properties; that might be associated with the major components and the minor components found in the essential oils.

关键词： Cymbopogon validus Essential oils Anti-inflammation Artemisia ketone Linalool Egg albumin-induced edema

Tailoring magnetic hysteresis of additive manufactured Fe-Ni permalloy via multiphysics-multiscale simulations of process-property relationships

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2023年第1期9卷 1297-1315页

作者： Yangyiwei Yang Timileyin David oyedeji Xiandong Zhou Karsten Albe Bai-Xiang Xu Mechanics of Functional Materials Division Institute of Materials ScienceTechnische Universität DarmstadtDarmstadt 64287Germany Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province College of Architecture and EnvironmentSichuan UniversityChengdu 610207China Materials Modelling Division Institute of Materials ScienceTechnische Universität DarmstadtDarmstadt 64287Germany

Designing the microstructure of Fe-Ni permalloy produced by additive manufacturing(AM)opens new avenues to tailor its magnetic ***,AM-produced parts suffer from spatially inhomogeneous thermal-mechanical and magnetic responses,which are less investigated in terms of process modeling and *** present a powder-resolved multiphysics-multiscale simulation scheme for describing magnetic hysteresis in AM-produced material,explicitly considering the coupled thermal-structural evolution with associated thermo-elasto-plastic behaviors and chemical order-disorder *** residual stress is identified as the key thread in connecting the physical processes and phenomena across *** employing this scheme,we investigate the dependence of the fusion zone size,the residual stress and plastic strain,and the magnetic hysteresis of AM-produced Fe_(21.5)Ni_(78.5) on beam power and scan *** results also suggest a phenomenological relation between magnetic coercivity and average residual stress,which can guide the magnetic hysteresis design of soft magnetic materials by choosing appropriate processing parameters.

关键词： alloy microstructure hysteresis

Bioaccumulation of heavy metals in some tissues of croaker fish from oil spilled rivers of Niger Delta region,Nigeria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2017年第6期7卷 563-568页

作者： Muawiya Musa Abarshi Edward oyedeji Dantala Sanusi Bello Mada Department of Biochemistry Ahmadu Bello University Zaria

Objective:To investigate the level of heavy metals(Cu,Zn,Fe Mn Ni,Pb and Cd) in muscles,gills and liver tissue of Croaker fish from oil spilled rivers of Bonny and Finima,Niger Delta region,***:Twenty four Croacker fishes(Genyonemus lineatus) weighing between 250 and 260 g and 24–26 cm length were collected from each sampling sites(Bonny and finima rivers).The frozen fishes were thawed and dried at 105C until they reach a constant *** dried samples were homogenized and digested with 10 ml tri-acid mixture(HNO3:HCl O4:H2SO4),and then the digested samples were diluted to 100 ml with deionized *** metals(Cu,Ni,Zn,Pb,Mn,Iron Fe,and Cd) concentrations were determined by atomic absorption ***:Our results revealed that concentrations and distribution patterns of all heavy metals studied varied significantly(P < 0.05) amongst the fish tissues analyzed and sampling ***,liver tissue of fish caught from Finima creek accumulated the highest concentrations of Cu(52.64 ± 3.01 mg/g dry wt),Zn(166.50 ± 6.45 mg/g dry wt)and Fe(801.50 ± 14.15 mg/g dry wt) in comparison to the liver of fish caught from Bonny river in which the levels of Cu,Zn and Fe were(45.00 ± 2.79),(49.90 ± 2.91) and(216 ± 6.11 mg/g dry wt),*** addition,Mn,Ni,Pb and Cd exhibited their highest concentrations in gills from both *** expected,muscle tissue contained the least concentrations of all metals investigated from both sampling ***,all the metals investigated exhibited highest concentration in fish collected from Finima *** abnormal high level heavy metals accumulation observed in this location could be linked to the frequent crude oil spills as well as industrial activity around the area which might get discharged into Finima *** general,the mean concentrations of some toxic heavy metals investigated exceed the recommended maximum permissible limits set by the Joint FAO/WHO ***,some metals

关键词： Croaker fish Heavy metals Bioaccumulation Oil spillage Niger Delta region

Genetic diversity of Plasmodium falciparum isolates from naturally infected children in north-central Nigeria using the merozoite surface protein-2 as molecular marker

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2013年第8期6卷 589-594页

作者： Segun Isaac oyedeji Henrietta Oluwatoyin Awobode Chiaka Anumudu Jrgen Kun Department of Biotechnology Bells University of Technology Parasitology Unit Department of Zoology University of Ibadan Institute of Tropical Medicine Eberhard Karls University

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.

关键词： Malaria Plasmodium falciparum MSP-2 Genetic diversity PCR North-central Nigeria

Phytochemical Screening of Two Tropical Moss Plants: Thidium gratumP. Beauv and Barbula indicaBrid Grown in Southwestern Ecological Zone of Nigeria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Analytical Chemistry 2012年第12期3卷 836-839页

作者： Adedeji O. Adebiyi ayodele A. oyedeji Elijah E. Chikwendu Olubunmi A. Fatoke Department of Chemistry Education Science Ekiti State University Ado Ekiti Nigeria Department of Plant Science Ekiti State University Ado Ekiti Nigeria

Chemical tests were carried out on the aqueous extracts of the air-dried powders of two tropical moss plants, Thidium gratum and Barbula indica using standard procedures, to identify the phytochemical constituents. The extracts were screened for the presence and quantities of alkaloids, flavonoids, phenols, saponins and steroids with a view to assess their therapeutic values in ethnomedicine. The results of the phytochemical screening revealed the presence of alkaloids, flavonoids, phenols, saponins and steroids in varying quantities in the two moss plants but there was absence of phenol in Barbula indica. These results suggest that the two moss plants can be veritable and potential source of useful drugs in treatment of ailments.

关键词： Phytochemical Constituents Extracts Moss Plants Ethnomedicine Ailments

Comparison of three PCR methods for detection of Helicobacter pylori DNA and detection of cagA gene in gastric biopsy specimens

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2004年第13期10卷 1958-1960页

作者： SI Smith KS oyedeji AO Arigbabu FCantet FMegraud OOOjo AOUwaifo JAOtegbayo SOOla AO Coker Molecular Biology and Biotechnology Division Nigerian Institute of Medical ResearchP.M.B. 2013YabaLagosNigeria Microbiology Division Nigerian Institute of Medical ResearchP.M.B. 2013YabaLagosNigeria Department of Surgery Obafemi Awolowo University Teaching Hospital ComplexIle-Ife Laboratoire de Bacteriologie BordeauxCedexFrance Department of Biochemistry University of IbadanIbadanNigeria Department of Medicine University of IbadanIbadanNigeria College of Medicine University of LagosIdi-ArabaLagosNigeria

AIM:To comparatively evaluate PCR and other diagnostic methods (the rapid urease test and/or culture) in order to determine which of the three PCR methods (ureA,glmM and 26-kDa,SSA gene) was most appropriate in the diagnosis of Helicobacterpylori(Hpylori) infection and also to evaluate the detection of a putative virulence marker of H pylori,the cage,gene,by PCR in biopsy specimens. METHODS:One hundred and eighty-nine biopsy specimens were collected from 63 patients (three biopsies each) undergoing upper gastroduodenal endoscopy for various dyspeptic *** PCR methods used to detect H pylori DNA directly from biopsies were the glmM,26-kDa, ureA and then cagA was used to compare the culture technique and CLO for urease with the culture technique being used as the gold standard. RESULTS:Thirty-five percent of the biopsies were positive for H pylori DNA using the 3 PCR methods,while 68% of these were positive for the cagA ***-four percent of the biopsies were negative for H pylori DNA in all PCR methods *** remaining 41% were either positive for ureA gene only,glmM only,26-kDa only,or ureA+glmM, ureA+26-kDa,glmM+*** of the 35% positive biopsies,41% and 82% were positive by culture and CLO respectively,while all negative biopsies were also negative by culture and *** A+ infection was also predominantly found in H pylori DNA of the biopsies irrespective of the clinical diagnosis. CONCLUSION:This method is useful for correctly identifying infections caused by H pylori and can be easily applied in our laboratory for diagnostic purposes.

关键词： Antigens, Bacterial Bacterial Proteins Biopsy Comparative Study Gastric Mucosa Helicobacter Infections Helicobacter pylori purification Humans Phosphoglucomutase Polymerase Chain Reaction Research Support, Non-U.S. Gov't Sensitivity and Specificity Urease Virulence

Predominant Lactic Acid Bacteria Involved in the Traditional Fermentation of Fufuand Ogi, Two Nigerian Fermented Food Products

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food and Nutrition Sciences 2013年第11期4卷 40-46页

作者： Olaoluwa oyedeji Samuel Temitope Ogunbanwo Anthony Abiodun Onilude Department of Microbiology Obafemi Awolowo University Ile-Ife Nigeria 2Department of Microbiology University of Ibadan Ibadan Nigeria. Department of Microbiology University of Ibadan Ibadan Nigeria.

Traditional methods of preparation were simulated in the laboratory fermentations of cassava and maize to produce fufu and ogi respectively. Changes in pH, temperature and titratable acidity, as well as the diversity of lactic acid bacteria species were investigated during both fermentations. Lactic acid bacteria strains involved in the fermentation processes were isolated at twelve hourly intervals, characterized and identified using phenotypic and biochemical methods. A rapid decrease in pH, 5.6 to 3.7 in fufu and 5.9 to 3.8 in ogi, were observed with temperature increasing from 26℃?to 30℃and 25℃?to 31℃?in fufu and ogi respectively. Most of the lactic acid bacteria strains isolated were homofermentative and heterofermentative Lactobacillus species and heterofermentative Leuconostoc species. Lactobacillus plantarum and Leuconostoc mesenteroides were the dominant lactic acid bacteria species in fufu while L. cellobiosus, L. plantarum and Lc. lactis were dominant in ogi fermentation. An ecological succession pattern in which Leuconostoc species were mostly isolated during early stages of fermentation with the final stages populated with Lactobacillus species was observed in both cases and is attributable to differential acid tolerance of the two genera. The frequencies of dominance of the strains in fufu were L. plantarum (56.25%), Lc. mesenteroides (18.75%), L. lactis (6.25%), L. coprophillus (6.25%), L. acidophilus (6.25%) and L. brevis (6.25%). The frequencies of dominance in ogi were L. cellobiosus (26.6%), Lc. lactis (26.6%), L. plantarum (20.0%), L. acidophilus (13.33%) and Lc. paramesenteroides (13.33%). The dominant strains can serve as potential starter cultures for fufu and ogi production.

关键词： Lactic Acid Bacteria Fermentation Fufu Ogi Cassava Maize Fermented Foods

Optimal Control of Wind Turbines under Islanded Operation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Intelligent Control and Automation 2017年第1期8卷 1-14页

作者： Magdi S. Mahmoud Mojeed O. oyedeji Systems Engineering Department King Fahd University of Petroleum and Minerals Dhahran KSA

In this paper, an optimal control scheme for wind turbine output torque and power regulation under the influence of wind disturbances is presented. The system considered is a dynamic mechanical-based model with pitch and generator torque actuators for controlling the pitch and generator torque. The performance of linear matrix inequality (LMI) formalism of linear quadratic regulator (LQR);linear quadratic regulator with integral action (LQRI) and model predictive control (MPC) were compared in response to a step change in wind disturbance. It is shown by Matlab simulation that the LQRI outperformed both LQR and MPC controllers.

关键词： Wind Turbine Linear Quadratic Regulator Linear Quadratic Regulator with Integral Action Model Predictive Control Output Torque Power Regulation