Authors:Henshaw Effiom, Josiah Lennox Abstract: Bacillus species are widely used for thermostable α-amylase production for various applications such as in the detergent and food industries. This research aimed to study the production of α-amylase by B. subtilis IMD34 in submerged fermentation conditions using Plackett-Burman (PB) design, along with the optimization of certain environmental factors for optimal growth of amylolytic bacteria. Plackett-Burman design was used to evaluate the effect of ten independent variables on α-amylase production. Maximum enzyme activity was recorded in a medium containing (g/l); starch (6.0), peptone (12.0), K2HPO4 (1.0), Na2HPO4 (2.0), NaCl (0.6), Na2SO4 (0.1), MgSO4.7H20 (1.0), FeCl3.6H2O (0.02), CaCl2.2H2O (0.02) and with an agitation speed (200 rpm). From the pareto chart it was observed that the most important independent variables for amylase production were starch, peptone, NaCl, Mg2SO4, CaCl2.2H2O and agitation. Optimization of environmental parameters to assess their effect on the growth of bacteria showed that optimal pH, incubation time and temperature were recorded at 6, 48h and 37˚C. Evaluating independent variables statistically using PB design revealed that some of the medium’s components had a positive impact on α-amylase production by B. subtilis IMD34. PubDate: 2022-11-29 DOI: 10.53539/squjs.vol27iss2pp77-83 Issue No:Vol. 27, No. 2 (2022)
Authors:Ebube Charles Amaechi, Miracle Innocent Dike, Onyinye Mkpola Ukpai, Blessing Uzoamaka Ejike Pages: 84 - 89 Abstract: Gastrointestinal parasitism in swine production is a world-wide problem especially in tropical resource-poor countries. These infections in animals result in significant economic losses. This study aimed to assess the prevalence and spectrum of gastrointestinal parasites of pigs reared in two research farms in Michael Okpara University of Agriculture, Umudike, South eastern Nigeria. From April, 2016 to July, 2016, 220 samples of pig faeces from two research farms (CASAP Research Farm and MOUAU Commercial Pig Farm) were analyzed using floatation and direct smear methods to identify varied parasitic stages present in the faeces. Data generated showed an overall prevalence of 64.6% (142/220) in the two farms. Five parasite species made up of four Nematode and one Cestode were observed namely Ascaris suum (26.4%), Trichuris suis (26.4%), Strongyloides spp (21.9%), Oesophagostomum dentatum (20.0%) and Pseudanoplocephala spp. (5.6%). Mixed infections were also observed. Those within the ages of 0-8months had the highest prevalence (74.12%). Further, 67.42% male pigs and 62.60% of female pigs were found to be infected with one or the other endoparasite revealing a high prevalence of parasitic problems within Umudike. It is recommended that pigs should be treated regularly to prevent or reduce infection to the barest minimal level. PubDate: 2022-11-29 DOI: 10.53539/squjs.vol27iss2pp84-89 Issue No:Vol. 27, No. 2 (2022)
Authors:Farzad Rahpeymaii, Majid Rostami Pages: 90 - 99 Abstract: There have been some conjugate gradient methods with strong convergence but numerical instability and conversely. Improving these methods is an interesting idea to produce new methods with both strong convergence and numerical stability. In this paper, a new hybrid conjugate gradient method is introduced based on the Fletcher formula (CD) with strong convergence and the Liu and Storey formula (LS) with good numerical results. New directions satisfy the sufficient descent property, independent of line search. Under some mild assumptions, the global convergence of new hybrid method is proved. Numerical results on unconstrained CUTEst test problems show that the new algorithm is very robust and efficient. PubDate: 2022-11-29 DOI: 10.53539/squjs.vol27iss2pp90-99 Issue No:Vol. 27, No. 2 (2022)
Authors:Mohammad Shahryari Pages: 100 - 106 Abstract: We define a topo-system on a group as a set of subgroups satisfying certain topology-like conditions. We study some fundamental properties of groups equipped with a topo-system (topo-groups) and using a suitable formalization of a subgroup filter, we prove a Tychonoff type theorem for the direct product of topo-compact topo-groups. PubDate: 2022-11-29 DOI: 10.53539/squjs.vol27iss2pp100-106 Issue No:Vol. 27, No. 2 (2022)
Authors:H.M. Nasir Pages: 107 - 118 Abstract: We present and investigate a new type of implicit fractional linear multi-step method of order two for fractional initial value problems. The method is obtained from the second-order superconvergence of the Grünwald-Letnikov approximation of the fractional derivative at a non-integer shift point. The method coincides with the backward difference method of order two for the classical initial value problem when the order of the derivative is one. The weight coefficients of the proposed method are obtained from the Grünwald weights and are hence computationally efficient compared with that of the fractional backward difference formula of order two. The stability properties are analyzed and it is shown that the stability region of the method is larger than that of the fractional Adams-Moulton method of order two and the fractional trapezoidal method. Numerical results and illustrations are presented to justify the analytical theories. PubDate: 2022-11-29 DOI: 10.53539/squjs.vol27iss2pp107-118 Issue No:Vol. 27, No. 2 (2022)
Authors:Mohammed Salim Jasim Al-Taie Pages: 119 - 124 Abstract: The objective of this research is to compare pulses travelling through different photonic crystal fiber cores (DPCFC) using both finite element method (FEM) /split step Fourier method (SSFM). A unique DCPCF design with exceptionally high non-linearity has been introduced to achieve ultra-high pulse amplitude. Via a generalized non-linear equation, we evaluate the refractive index ratio and dispersion, for each type which is used, as well as output amplitude for different cores in different photonic crystal fiber core by utilizing the solution for the nonlinear Schrodinger equation (NLSE). Lastly, the findings are compared to different photonic crystal fiber design parameters. This paper provides a photonic crystal fiber design consisting of multiple liquid cores and theoretically solved non-linear equations. It was discovered in this design that the refractive index of propylene glycol (C3H8O2) is greater than ethylene glycol’s (C2H6O2), and that both are far greater than silica's refractive index (SiO2). Propylene (C3H8O2) has a lower dispersion than ethylene glycol (C2H6O2) and silica (SiO2). The output amplitudes of (C3H8O2) and (C2H6O2) were then shown to be substantially bigger than the output amplitudes of (SiO2) with respect to distance and time. This emphasizes the need for using certain liquids as cores in holey fibers, dependent upon their use. PubDate: 2022-11-29 DOI: 10.53539/squjs.vol27iss2pp119-124 Issue No:Vol. 27, No. 2 (2022)
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