• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.425-431
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• 1996

The enzymatic characteristics of Alcaligenes latus were investigated by measuring the variations of various enzyme activities related to biosynthesis and degradation of poly-${\beta}$-hydroxybutyrate (PHB) during cultivation. All PHB biosynthetic enzymes, ${\beta}$-ketothiolase, acetoacetyl-CoA reductase, and PHB synthase, were activated gradually at the PHB accumulation stage, and the PHB synthase showed the highest value among three enzymes. This indicates that the rate of PHB biosynthesis is mainly controlled by either ${\beta}$-ketothiolase or acetoacetyl-CoA reductase rather than PHB synthase. The enzymatic activities related to the degradation of PHB were also measured, and the degradation of PHB was controlled by the activity of PHB depolymerase. The effect of supplements of metabolic regulators, citrate and tyrosine, was also investigated, and the activity of glucose-6-phosphate dehydrogenase was increased by metabolic regulators, especially by tyrosine. The activities of ${\beta}$-ketothiolase and acetoacetyl-CoA reductase were also activated by citrate and tyrosine, while the activity of PHB depolymerase was depressed. The increased rate and yield of PHB biosynthesis by metabolic regulators may be due to the increment of acetyl-CoA concentration either by the repression of the TCA cycle by citrate through product inhibition or by the activation of sucrose metabolism by the supplemented tyrosine.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1047-1052
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• 2004

The genomes of Chinese native chicken populations were screened using microsatellites as molecular markers. A total of, 528 individuals comprisede12 Chinese native chicken populations were typed for 7 microsatellite markers covering 5 linkage groups and genetic variations and genetic distances were also determined. In the 7 microsatellite loci, the number of alleles ranged from 2 to 7 per locus and the mean number of alleles was 4.6 per locus. By using fuzzy cluster, 12 Chinese native chicken populations were divided into three clusters. The first cluster comprised Taihe Silkies, Henan Game Chicken, Langshan Chicken, Dagu Chicken, Xiaoshan Chicken, Beijing Fatty Chicken and Luyuan Chicken. The second cluster included Chahua Chicken, Tibetan Chicken, Xianju Chicken and Baier Chicken. Gushi Chicken formed a separate cluster and demonstrated a long distance when comparing with other chicken populations.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.962-966
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• 2020

Monitoring the mutation dynamics of human severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical in understanding its infectivity, virulence and pathogenicity for development of a vaccine. In an "age of mobility," the pandemic highlights the importance and vulnerability of regionalization and labor market interdependence in Southeast Asia. We intend to characterize the genetic variability of viral populations within the region to provide preliminary information for regional surveillance in the future. By analyzing 142 complete genomes from South East Asian (SEA) countries, we identified three central variants distinguished by nucleotide and amino acid changes.

• Toxicological Research
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• v.18 no.4
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• pp.341-347
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• 2002

Hypertension is a multifactorial disorder in which the genetic and environmental factors are involved. In a view of the effects for hypertension as a risk factor for hypertension, we investigated the genotype and allele frequencies in the four RFLPs of the apo AI-CIII-AIV gene cluster (G to A mutation at position -75 in the apo AI promoter SstI RFLP in the ape CIII gene and HincII and HinfI RFLPs in the apo AIV gene) in the Korean patients with hypertension and normal controls. The AA genotype frequency of the G to A promoter polymorphism in hypertensives was significantly higher than that of normotensives (P < 0.05). None of the other polymorphisms showed a difference in genotype frequency between two groups. Therefore, our result suggest that the G to A promoter polymorphism of the ape AI gene may be useful as genetic marker in the ethiology of hypertension.

• Journal of applied mathematics & informatics
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• v.19 no.1_2
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• pp.397-414
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• 2005

In the existing literature, most of the purchasing models were developed only for retailers problem ignoring the constraint of storage capacity of retailers shop/showroom. In this paper, we have developed a deterministic model of wholesaler-retailers' problem of single product. The storage capacity of wholesaler's warehouse/showroom and retailers' showroom/shop are assumed to be finite. The items are transported from wholesaler's warehouse to retailers' Own Warehouse (OW) in a lot. The customer's demand is assumed to be displayed inventory level dependent. Demands are met from OW and that spaces of OW will immediately be filled by shifting the same amount from the Rented Warehouse (RW) till the RW is empty. The time duration between selling from OW and filling up its space by new ones from RW is negligible. According to relative size of the retailers' existing (own) warehouse capacity and the demand factors, different scenarios are identified. Our objectives are to optimize the cost functions of wholesaler and two retailers separately. To solve this problem, a real coded Genetic Algorithm (GA) with roulette wheel selection/reproduction, whole arithmetic crossover and non-uniform mutation is developed. Finally a numerical example is presented to illustrate the results for different scenarios. To compare the results of GA, Generalised Reduced Gradient Method has been used for the problem. Also, a sensitivity analysis has been performed to study the variations of the optimal average cost with respect to the different parameters.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.2
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• pp.145-152
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• 1999

This paper presents an optimal design method for fuzzy logic controllers using genetic algorithms. In general, the design of fuzzy logic controllers has difficulties in the acquisition of exper's knowledge and relies to a great extent on empirical and heuristic knowledge which, in many cases, cannot be objectively justified. So, the performance of the controller can be degraded in the case of plant parameter variations or unpredictable incident which the designer may have ignored, and parameters of the fuzzy logic controller obtained by expert's control action may not be global. To solve these problems, the proposed method using genetic algorithms in this paper, can tune the parameters of fuzzy logic controller including scaling factors and determine the appropriate number of fuzzy reles systematically and automatically. We provide the second drder dead time plant and inverted pendulum system to evaluate the feasibility and generality of our proposed method. Comparison shows that the proposed controller can producd higher accuracy and a smaller number of fuzzy rules than manually tuned fuzzy logic controller.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.115-122
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• 2015

Anthracnose, caused by Colletotrichum gloeosporioides (C. gloeosporioides; Teleomorph: Glomerella cingulata), is the most destructive disease that affects sweet persimmon production worldwide. However, the biology, ecology, and genetic variations of C. gloeosporioides remain largely unknown. Therefore, in this study, the development of fungicide resistance and genetic diversity among an anthracnose pathogen population with different geographical origins and the exposure of this population to different cultivation strategies were investigated. A total of 150 pathogen isolates were tested in fungicide sensitivity assays. Five of the tested fungicides suppressed mycelial pathogen growth effectively. However, there were significant differences in the sensitivities exhibited by the pathogen isolates examined. Interestingly, the isolates obtained from practical management orchards versus organic cultivation orchards showed no differences in sensitivity to the same fungicide. PCR-restriction fragment length polymorphism (RFLP) analyses were performed to detect internal transcribed spacer regions and the ${\beta}$-tubulin and glutamine synthetase genes of the pathogens examined. Both the glutamine synthetase and ${\beta}$-tubulin genes contained a complex set of polymorphisms. Based on these results, the pathogens isolated from organic cultivation orchards were found to have more diversity than the isolates obtained from the practical management orchards.

• Animal cells and systems
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• v.1 no.4
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• pp.529-534
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• 1997

Genetic and morphological variations of Rhinogobius giurinus were surveyed. Populations of R.giurinus were clearly divided into two forms (Form-A and Form-B). Starch gel variation of this species. Three loci (Aco, Mpi, aGpd) out of 27 showed fixed allelic differences between Form-A and Form-B and they are well differentiated from each other genetically (Rogers' S=0.871). These two forms, moreover, are found to be allopatric in distribution and morphologi cally different in body length and caudal fin color pattern. Therefore, they are considered as two distinct taxa of subspecific rank. In addition, the genetic relationships among 5 taxa within 4 species of the genus Rhinogobius were investigated. Three species of the Rhinogobius brunneus complex (R.sp. OR, R. sp. CB and R. sp. CO) are well differentiated from each other genetically and two taxa of R. giurinus are genetically divergent from three species of the Rhinosotius brunneus complex (average Nei's D=0.603, average Rogers'=0.534).

• Animal cells and systems
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• v.4 no.1
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• pp.31-37
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• 2000

The genetic variations among six species of Rana from Korea (R. nigro-maculata, R. piancyi, R. dybowskii, R. sp, R. rugosa type A, B and R. amurensis) were investigated using 499 bases of mitochondrial DNA sequences for ND2 (NADH dehydrogenase subunit 2) gene and $tRNA^{Trp}$ gene. Partial sequences of ND2 gene (427 bp) and full sequences of $tRNA^{Trp}$ gene (73 bp) were identified. The level of sequence divergences ranged from 0.2 to 5.2% within species and 4.9-28.0% among 6 species of the genus Rana. The $tRNA^{Trp}$ gene of the genus Rana was composed of 77 nucleotides which showed a two dimensional "cloverleaf" structure. The secondary structure of $tRNA^{Trp}$ was not found compensatory changes which could potentially confound phylogenetic inference. In the neighborjoining tree, brown frogs were clustered first with the level of sequence divergence of 13.20% between R. amurensis and R. dybowskii, and 9% between R. dybowskii and R. sp. supported by 99% bootstrap iterations, respectively. R. nigromaculata and R. plancyi were clustered into another group with 5.1% divergence supported by 100% bootstrap iteration. R. rugosa A 8nd B types were grouped by 4.9% divergence and clustered into the last group with other two groups with 100% bootstrap iterations.

• Computers and Concrete
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• v.6 no.4
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• pp.343-356
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• 2009

Experiments were designed to investigate the flow behavior of portland cement paste and concrete incorporating superplasticizers. The paste and concrete mixtures were subjected to prolonged mixing for up to 110 min at high temperature. The yield stress values of concrete and that of the corresponding cement paste were measured using a rotating rheometer and viscometer, respectively. The results reveal a weak linear correlation between the yield stress of concrete mixtures and that of the corresponding cement pastes. Results also indicate that the yield stress of concrete varies in a linear fashion with the elapsed time, while its variations with the temperature and superplasticizer dosage follow power and inverse power functions, respectively. In this study, the genetic algorithms (GA) technique was used to predict the yield stress of concrete considering various parameters, such as the mixing time, ambient temperature, and superplasticizer dosage. A sensitivity study was conducted to evaluate the ability of the GA equations thus developed to capture the effects of test parameters on the yield stress of concrete. It was found that the GA equations were sensitive to the effects of test parameters and provided yield stress predictions that compared well with corresponding experimental data.