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Perceptions and Use of Open Access Journals by Nigerian Postgraduate Students
Ayeni, Philips Oluwaseun Korea Institute of Science and Technology Informat 2017 Journal of Information Science Theory and Practice Vol.5 No.1
This article investigates perceptions and use of Open Access journals (OAJs) by master's degree students in two universities in the southwestern part of Nigeria. A descriptive survey design was used in the study and the study population was comprised of 7,423 master's degree students in the University of Ibadan and 1,867 from Obafemi Awolowo University. A multistage random sampling technique was used to select a sample size of 249 and the data collection instrument was a structured questionnaire. Data were analyzed using frequency counts, percentages, mean, standard deviation, correlation, and regression analyses. The findings revealed that OAJs were used for learning, dissertation writing, personal research, and development. OAJs were not frequently used because of download delays, unavailability of Internet facilities, and limited access to computers terminals, among other issues. OAJs were found to be of relative advantage, positively perceived, and found to be compatible with existing values and quality assurance in scholarly publications, hence their use for academic activities. The regression analyses showed that there was a significant positive relationship between positive perception, perception of relative advantage, perception of compatibility, perception complexity, and master's degree students' use of OAJs. Negative perception was found to have a significant negative correlation with the use of OAJs. This article recommends that quality assurance of OAJs should be ensured in order to boost users' positive perceptions to increase their patronage and usage of these scholarly outlets for various academic activities, which will in turn encourage research and development across the various institutions of higher learning in Nigeria.
Augustine Omoniyi Ayeni,Ram Awtar Pandey,James Abiodun Omoleye,Sandeep Mudliar,Fredrick Kofi Hymore 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.7
Enzymatic hydrolysis and fermentation methods were evaluated on alkaline peroxide pretreated shea treesawdust conversion to ethanol. Optimum pretreatment conditions of 120 oC reaction temperature, 30min reaction time,and 20 mL L−1 of water hydrogen peroxide concentration (1%(v/v)H2O2) solubilized 679 g kg−1 of hemicellulose and172 g kg−1 of lignin. 617 g kg−1 cellulose was retained in the solid fraction. The maximum yield of reducing sugar withoptimized enzyme loadings by two enzyme preparations (cellulase and β-glucosidase) was 165 g kg−1 of dry biomass. The ethanol yield was 7.35 g L−1 after 72 h incubation period under the following conditions: 2% cellulose loading,enzyme concentration was 25 FPU (g cellulose)−1 loading, yeast inoculums was 10% (v/v), 32 oC, and pH 4.8. Thepretreatments gave information about the hindrances caused by lignin presence in lignocellulosic materials and thathemicelluloses are better hydrolyzed than lignin, thereby enhancing enzymatic digestibility of the sawdust material.
Augustine Omoniyi Ayeni,Oluranti Agboola,Michael Olawale Daramola,Bianca Grabner,Babalola Aisosa Oni,Damilola Elizabeth Babatunde,Joseph Evwodere 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.1
Corn cob lignocellulosic biomass is one of the useful precursors for the alternative production of fuels and chemicals. Understanding the kinetics of enzymatic conversion of corn cob through kinetic models could provide indepth knowledge and increase the predictive ability for process design and optimization. In this study, models based on the semi-mechanistic rate equations, first-order decay exponential function of time for adsorbed enzymes, structural and diffusion coefficient for adsorption were used to estimate kinetic parameters for the enzymatic conversion of alkaline peroxide oxidation (APO) pretreated corn cob to sugar. Fitting a first-order inactivation model of adsorbed cellulases to account for experimental hydrolysis data, the apparent hydrolysis rate constant (k2=29.51 min1), the inactivation rate constant (k3=0.269min1), and reactivation rate constant (k4=0.0048min1) were estimated. Regressed values of apparent maximum rate, Vmax, app, for adsorbed enzymes reduced appreciably with time to more than 98% at 96 h. The diffusion limit model showed that the diffusion resistance increased with increasing enzyme concentrations.
Financial Development and Shadow Economy in Africa: Evidence from Panel Quantile Regression
Ifeanyi Onwuka,Emmanuel Ayeni 중앙대학교 경제연구소 2023 Journal of Economic Development Vol.48 No.2
The study investigated the impact of financial development on shadow economy in Africa, using data for 41 African countries. The informal outputs, computed by Elgin et al. (2021), and the three financial development indicators were sourced from the World Bank and International Monetary Fund (IMF) respectively. The dynamic panel quantile regression technique was employed as it captures better the nature of the African economy and the heterogeneous nature of the shadow economies. The study shows that average FIA and FID in Africa is 0.074 and 0.160 respectively; suggesting that accessing credit from financial institution, as well as the coverage of credit and other financial services in Africa is low, and could be accompanied with high degree of bottlenecks. The FIE on average is 0.520; suggesting that credits from financial institution in Africa are used for their intended purposes. However, financial development must be pursued alongside other macroeconomic goals, particularly urbanization.
Permethrin exposure affects neurobehavior and cellular characterization in rats’ brain
Gabriel Omotoso,Olajumoke Oloyede,Shakirah Lawal,Ismail Gbadamosi,Nafisat Mutholib,Fatimah Abdulsalam,Abdulkabir Bature,Abdulsalam Babalola,Busola Ayeni,Nathaniel Amedu 환경독성보건학회 2020 환경독성보건학회지 Vol.35 No.4
This study investigated the neurotoxic effects of permethrin on the cerebellum, hippocampus and prefrontal cortex of Wistar rats and its effects on some behavioral patterns. Fifteen adult male Wistar rats were grouped into three categories: Group A received 0.1 mL normal saline (control), and Groups B and C received mixed feed with 500 ㎎/㎏ and 1,000 ㎎/㎏ of 0.6% permethrin, respectively, for 14 days. The animals were assessed for memory, anxiety and exploratory locomotion and thereafter anesthetized and transcardially perfused with normal saline and 4% paraformaldehyde (PFA). Cerebellum, hippocampus and prefrontal cortex were excised from the whole brain and processed for tissue histology, histochemistry and immunohistochemistry. Oxidative status and lipid peroxidation were also assessed using catalase, glutathione peroxidase, superoxide dismutase and malondialdehyde as biomarkers. Results revealed dose-dependent decrease in body weights but increase in cerebellar and prefrontal weights, depletion of endogenous antioxidant markers, cognitive deficits, reduced locomotor activities, degenerative changes in the microarchitecture at high doses and presence of chromatolytic cells at both low and high doses of permethrin. Astrocytes were activated while synaptophysin expression was downregulated. Permethrin causes dose-dependent neurotoxicity on the morphology, neurochemistry and oxidative status of different brain regions, and these could affect behavioral performance and other neurologic functions.