• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.691-699
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• 2021

The global surface temperature has risen critically over the past century and according to the IPCC Fifth Assessment Report 2014, existing risks in natural and human systems will worsen. Coastal erosion is mostly caused by climate change and among all the coastal areas at risk, Benin, which is part of the Gulf of Guinea, has been ranked very highly as a vulnerable region. Therefore, in this review, we focus on the evolution of coastline change in Cotonou of Benin, summarizing its resultant impacts and applied measures around the coast area by reviewing previous studies. Signs of coastal erosion in Cotonou appeared in 1963. After 39 years, the east shoreline of Cotonou has retreated by 885 m, resulting in the disappearance of more than 800 houses. To solve this problem, Benin authorities built seven groynes in 2013, and have increased the number of the structure as a way to interrupt water flow and limit the movement of sediment. Over the region, shorelines appeared preserved accordingly. In contrast, areas located further east, where groynes were not installed, have suf ered from intensive erosion at a rate of 49 m/yr. In the future, as a next step, the effectiveness of groynes should be studied with local and broader perspectives.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.1
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• pp.54-57
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• 2016

Controlled ovarian hyperstimulation is one of the major steps of in vitro fertilization. The inaccessibility or non-visualization of developing follicles on transvaginal sonography (the preferred imaging method) may be misjudged as a poor response, resulting in cycle cancellation. It is necessary to scrupulously appraise proxy indicators for ovarian response, such as estradiol levels, endometrial thickness, and other individual clinical characteristics. This can prompt meticulous transabdominal ultrasound follicular monitoring and oocyte retrieval with the goal of averting cycle cancellation and improving treatment outcomes.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.25 no.4
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• pp.224-261
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• 2021

The interest in implicit-explicit (IMEX) integration methods has emerged as an alternative for dealing in a computationally cost-effective way with stiff ordinary differential equations arising from practical modeling problems. In this paper, we introduce implicit-explicit second derivative linear multi-step methods (IMEX SDLMM) with error control. The proposed IMEX SDLMM is based on second derivative backward differentiation formulas (SDBDF) and recursive SDBDF. The IMEX second derivative schemes are constructed with order p ranging from p = 1 to 8. The methods are numerically validated on well-known stiff equations.

• Journal of Plant Biology
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• v.33 no.3
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• pp.169-172
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• 1990

The epidermal structure and development of stomata in four taxa of Zingiberaceae viz: Aframomum melegueta K. Schum, Aframomum sceptrum K. Schum, Curcuma longa L. and Zingiber officinale Rosc. have been investigated. Unicellular, eglandular trichomes are observed on the epidermis of A. sceptrum and Z. officienal. Anomocytic stomata with agenous ontogeny, paracitic stomata with eumesogenous ontogeny and tetracytic stomata with mesoperigenous ontogency are recorded in Z. officinale, Aframomum species and C. longa respectively. Stomata of Z. officinale are the smallest in size (20.6$\times$14.3$\times$10.5${\mu}{\textrm}{m}$) while those of C. longa are the largest (42.5$\times$31.5$\times$20.2${\mu}{\textrm}{m}$). These two taxa also recorded the highest (43.7/mm2) and lowest (28.6/mm2) stomatal frequency respectively which suggests a linear regression of frequency on size.

• The Plant Pathology Journal
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• v.37 no.4
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• pp.375-388
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• 2021

Rice yellow mottle virus (RYMV) is the most harmful virus that affects irrigated and lowland rice in Africa. The RBe24 isolate of the virus is the most pathogenic strain in Benin. A total of 79 genotypes including susceptible IR64 (Oryza sativa) and the resistant TOG5681 (O. glaberrima) as checks were screened for their reactions to RBe24 isolate of RYMV and the effects of silicon on the response of host plants to the virus investigated. The experiment was a three-factor factorial consisting of genotypes, inoculation level (inoculated vs. non-inoculated), and silicon dose (0, 5, and 10 g/plant) applied as CaSiO₃ with two replications and carried out twice in the screen house. Significant differences were observed among the rice genotypes. Fifteen highly resistant and eight resistant genotypes were identified, and these were mainly O. glaberrima. Silicon application did not affect disease incidence and severity at 21 and 42 days after inoculation (DAI); it, however, significantly increased plant height of inoculated (3.6% for 5 g CaSiO₃/plant and 6.3% for 10 g CaSiO₃/plant) and non-inoculated (1.9% for 5 g CaSiO₃/plant and 4.9% for 10 g CaSiO₃/plant) plants at 42 DAI, with a reduction in the number of tillers (12.3% for both 5 and 10 g CaSiO₃/plant) and leaves (26.8% for 5 g CaSiO₃/plant and 28% for 10 g CaSiO₃/plant) under both inoculation treatments. Our results confirm O. glaberrima germplasm as an important source of resistance to RYMV, and critical in developing a comprehensive strategy for the control of RYMV in West Africa.

• Advances in environmental research
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• v.2 no.2
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• pp.119-129
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• 2013

The study examined the effect of urbanization on the water quality of Nwaorie and Otamiri Rivers in Owerri metropolis, Imo State, South-East Nigeria. Water samples were collected from Nwaorie and Otamiri Rivers from four sampling stations up and down stream. Water parameters analyzed using standard procedures were: color, turbidity, temperature, pH, total hardness, total solids, metals (Iron and magnesium), anions (nitrate and ammonia) and Fecal coliform. Results showed increased levels of coloration, iron, ammonia, turbidity and fecal coliform which exceeded the World Health Organization (WHO) permissible limits for drinking water. Increase in these parameters indicated influx of industrial effluent from the nearby industries and indiscriminate disposal of wastes at the bank of the rivers. Application of ANOVA showed various degree of variation in pollutants levels between the two rivers and at different sampling points. River Nwaorie was observed to be more impacted than River Otamiri. High values of iron observed from the study could be deleterious to human health if the river water is consumed without treatment. The study, therefore, recommended proper waste management and disposal as well as effluent treatments in Owerri municipal against pollution of surface water.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.24 no.3
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• pp.243-291
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• 2020

In this paper, multi-block generalized backward differentiation methods for numerical solutions of ordinary differential and differential algebraic equations are introduced. This class of linear multi-block methods is implemented as multi-block boundary value methods (MB₂ VMs). The root distribution of the stability polynomial of the new class of methods are determined using the Wiener-Hopf factorization of a matrix polynomial for the purpose of their correct implementation. Numerical tests, showing the potential of such methods for output of multi-block of solutions of the ordinary differential equations in the new approach are also reported herein. The methods which output multi-block of solutions of the ordinary differential equations on application, are unlike the conventional linear multistep methods which output a solution at a point or the conventional boundary value methods and multi-block methods which output only a block of solutions per step. The MB₂ VMs introduced herein is a novel approach at developing very large scale integration methods (VLSIM) in the numerical solution of differential equations.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.1-20
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• 2006

This paper presents the interior penalty discontinuous Galerkin finite element methods (DGFEM) for solving the rotating disk electrode problems in electrochemistry. We present results for the simple E reaction mechanism (convection-diffusion equations), the EC' reaction mechanism (reaction-convection-diffusion equation) and the ECE and $EC_2E$ reaction mechanisms (linear and nonlinear systems of reaction-convection-diffusion equations, respectively). All problems will be in one dimension.

• Safety and Health at Work
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• v.7 no.3
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• pp.218-224
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• 2016

Background: Butchering is often associated with high rates of work-related musculoskeletal disorders (WRMSDs). However, published work on the prevalence of WRMSDs among butchers in Nigeria is scarce. This is important because meat processing practices differ across geographical and cultural locations. This study was therefore aimed at analyzing WRMSDs among butchers in Kano metropolis. Methods: Sociodemographic and work-settings information was obtained from 102 male cattle butchers (age, $37.49{\pm}11.68years$) through survey. Information on the prevalence and pattern of musculoskeletal disorders was obtained from the respondents using the Standardized Nordic Questionnaire. Additional information on health seeking practices was also obtained using a pro forma. Associations between the prevalence of WRMSDs and each of the sociodemographic data and work settings were explored using Chi-square analysis. The level of significance was set at p < 0.05. Results: The 12-month and point prevalence rates of WRMSDs among butchers in this study were 88.2% and 74.5%, respectively. Whereas lower back complaints (66.7%) were the overall and lower body quadrant's most commonly reported WRMSDs among the butchers surveyed, wrist/hand complaints were the leading upper quadrant's (45.1%) most commonly reported WRMSDs among the respondents. There were significant associations between age and majority of WRMSDs in the body regions. Only 23.3% of the 90 individuals who had WRMSD visited the hospital to seek redress for their WRMSD. Conclusion: The prevalence of WRMSDs is high among butchers in Kano Metropolis. Few individuals with WRMSD utilize healthcare facilities. Age is a major risk factor in this setting.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.1
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• pp.51-61
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• 2016

In order to provide recommendations on the most useful forage species to smallholder farmers, eleven grass and eleven legume forages grown in Abomey-Calavi in Republic of Benin were investigated for nutritive value (i.e. chemical composition and energy content) and fermentation characteristics (i.e. gas and volatile fatty acid production, organic matter degradability). The in vitro gas production technique was used, incubating the forages for 120 h under anaerobic condition with buffalo rumen fluid. Compared to legume, tropical grass forages showed lower energy (8.07 vs 10.57 MJ/kg dry matter [DM]) and crude protein level (16.10% vs 19.91% DM) and higher cell wall content (neutral detergent fiber: 63.8% vs 40.45% DM), respectively. In grass forages, the chemical composition showed a quite high crude protein content; the in vitro degradability was slightly lower than the range of tropical pasture. The woody legumes were richer in protein and energy and lower in structural carbohydrates than herbaceous plants, however, their in vitro results are influenced by the presence of complex compounds (i.e. tannins). Significant correlations were found between chemical composition and in vitro fermentation characteristics. The in vitro gas production method appears to be a suitable technique for the evaluation of the nutritive value of forages in developing countries.