• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.209-218
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• 2006

This study was to evaluate microcystin production by two strains of cyanobacteria (Microcystis aeruginosa and Planktothrix agardhii) in response to three different levels of direct (0,4,8 inds.) or indirect (0,25, 50% of zooplankton culture media filtrate) exposures to zooplankton (Daphnia magna and Moina macrocopa). The cell biomass and intracellular microcystin (MC) were measured everyday. The survival rates of zooplankton were evaluated for daily intervals for the direct exposure. The intracellular MC produced peaked on the day 3 or 4, and then decreased over the both exposure experiment. In the direct experiment, the MC values were significantly different among the control and zooplankton treatments (ZT; repeated measures-ANOVA: P< 0.039). The MC contents of P. agardhii strain (No.204) were significantly higher (Tukey test, P< 0.082) in ZT2 (8 inds.) than in ZT2 (4 inds.). On the peak day, the intracellular MC exposed to both zooplanktons was significantly higher than the control (One-way ANOVA, P< 0.021). Higher zooplankton survivals were observed in the M. aeruginosa strain (No. 111) rather than in high toxic P. agardhii strain. In the indirect experiment, the intracellular MC of the M. aeruginosa strain was significantly different among the control and zooplankton culture media filtrate (ZCMF)treatments (rm-ANOVA: P<0.004), The MC exposed ZCMF2 (50%) were significantly higher than in ZCMFI (25%: Tukey test, P< 0.025) for both strains. This study strongly supports the induced-defensive MC production of potentially toxic cyanobacteria in response to the presence of zooplankton.

• Journal of Embryo Transfer
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• v.29 no.3
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• pp.297-303
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• 2014

The objective of this study was to determine the breed differences in the 3'-untranslated region (UTR) of MC1R mRNA, which may be used to distinguish Korean brindle cattle (Chikso) from other breeds. We investigated the relationship between the variation of 3'-UTR of the MC1R mRNA and coat color among different breeds and the Korean brindle cattle with different coat colors. MC1R mRNA expression levels were determined in accordance with the coat color and hair colors of the tail. Total cellular RNA was extracted from the hair follicles of the tails in Hanwoo, Korean brindle cattle, Holstein and $Hanwoo{\times}Holstein$ crossbred cattle. After cDNA synthesis, PCR was performed. Sequences of the 3'-UTR of MC1R mRNA were analyzed. The 3'-UTR of the MC1R mRNA from different breeds of cattle did not show any variations. There were no variations in the 3'-UTR of the MC1R mRNA in Korean brindle cattle with different coat colors. The levels of MC1R mRNA expression in hair follicles of the tail varied substantially among the Korean brindle cattle with different coat colors, except yellow coat color. Correlation between the MC1R mRNA expression in the hair follicles of the tail and coat color may be present in the Korean brindle cattle, but not between the variations of 3'-UTR of MC1R mRNA and coat color. Further studies to determine the regulation of MC1R mRNA expression from the hair follicles of different coat colors will be beneficial in clarifying the role of MC1R in the coat colors of the Korean brindle cattle.

• Journal of Animal Science and Technology
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• v.49 no.4
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• pp.437-442
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• 2007

The melanocortin-4 receptor(MC4R) is virtually expressed in all brain regions and plays an important role in energy homeostasis in mammals. MC4R has been intensively studied as a trait gene controlling economically important traits, such as growth and feed conversion, etc. Six hundreds and sixty Duroc pigs were genotyped for the MC4R locus and analyzed their relationships with breeding values for average daily gain(ADG), backfat thickness(BF), days to 90kg(D90) and feed conversion(FC). The estimated genotype frequencies for the all Duroc pigs were: 30.8%, 45.2%, 24.1% for AA, AB and BB genotypes, respectively. The mutant A allele was significantly associated with ADG, D90 and BF whereas no significant relationship was found with FC. The change of gene frequencies by generation was shown in both selected and culled groups. These results indicate that the MC4R polymorphism could be integrated in the present selection program to realize a marker-assisted selection for the growth traits of the Duroc population.

• Journal of Life Science
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• v.32 no.2
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• pp.125-134
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• 2022

This study investigated whether or not the major bioactive compounds of Noni (Morinda citrifolia) are involved in anti-inflammatory activity through the JAK/STAT upper signaling pathway in RAW 264.7 cells. The experimental results show that the M. citrifolia ethyl acetate fraction (Mc-EtOAc) obtained by sequential fractionation with organic solvents from the plant's dried fruits exhibits the highest antioxidant activity. In addition, the cytoprotective effects of Mc-EtOAc against H₂O₂-induced oxidative stress in the RAW 264.7 cells suppressed cytotoxicity in a dose-dependent manner. The group pretreated with Mc-EtOAc at a concentration of 240 ㎍/ml showed higher cell viability of 84.5%, compared to 71.6% in the LPS-treated group, and LPS-induced NO production decreased to half the amount in the positive control group. Mc-EtOAc treatment also led to a significant dose-dependent reduction in iNOS expression. Although COX-2 expression was increased by 300% following LPS induction, it was significantly decreased in a dose-dependent manner by pretreatment with Mc-EtOAc at concentrations of 120 and 240 ㎍/ml. An inhibition of the mRNA expression of pro-inflammatory cytokines IL-1β and TNF-α was observed. The investigation also revealed that the phosphorylation levels of pJAK1 and pSTAT3 in LPS-induced RAW 264.7 cells were significantly reduced by Mc-EtOAc treatment.

• Nutritional Sciences
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• v.8 no.1
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• pp.35-41
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• 2005

Controlling dietary behaviors and health-related lifestyle habits is important to manage non-insulin dependent diabetes mellitus (NIDDM). If NIDDM is not treated properly, the prevalence of macro-vascular complications (MC) may increase. The goal of NIDDM therapy is to maintain normal concentrations of blood glucose and lipid profiles by having regular meals, controlling alcohol drinking, quitting smoking, and performing physical exercise regularly. This study was performed to investigate the dietary and health-related lifestyle habits and blood parameters of NIDDM patients of both genders and compared these characteristics between the patients with and without MC. Our results show that the subjects with MC compared to without MC and the female patients than the males controlled their diets more regularly, tended to regulate the number of meals better, and smoke less than those without MC. Although plasma lipid profiles were not significantly different between the genders and between the subjects with and without MC, the men had higher blood glucose and plasma tHcy concentrations than the women and plasma tHcy concentration was higher in the female subjects without MC. These results imply that the male patients of NIDDM without MC might have more problems in maintaining their blood glucose. In addition, smoking may be the most important life-style factor influencing some blood parameters like blood glucose, HbAlc, and total cholesterol in the NIDDM patients.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.6
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• pp.31-37
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• 2010

In this paper, a performance of a decorrelating detector for a multirate MC(multi-carrier) DS/CDMA system is analyzed and simulated in a frequency selective Rayleigh fading channel. The performance is compared with that of single rate MC-DS/CDMA system in term of bit error probability. Variable Spreading Length (VSL) is employed for MC-DS/CDMA system as multirate transmission scheme. From simulation result, it is shown that Decorrelator for multirate MC-DS/CDMA achieves high BER performance as well as that of single rate case.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.951-958
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• 2020

This study examines the relationship between social media marketing and brand loyalty through brand trust. Respondents were drawn from customers of McDonald's, Malang City, East Java Province, Indonesia. For this study, 130 questionnaires were distributed and data were analyzed using the Structure Equation Model (SEM) version 22 of the AMOS (Analysis of Moment Structure) application. The results showed that social media marketing had an impact on increasing McDonald's brand trust and brand loyalty. Brand trust influences brand loyalty and brand trust can mediate the influence of social media marketing on McDonald's brand loyalty. The findings prove that brand trust can mediate the effect of social media marketing on customer loyalty to McDonald's brand. These results can be explained by the fact that marketing strategies through social media marketing, such as making it easy for customers to get information related to McDonald's on social media, can contribute to customer trust and that trust is formed because McDonald's always pays attention to the quality of the products offered. Brand trust can mediate the influence of social media marketing on customer loyalty to McDonald's brand. This means that information related to McDonald's on social media is proportional to the quality of the product offered.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.2
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• pp.117-125
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• 2003

In this paper, we propose a new code acquisition architecture having the features of low complexity and high speed for the MC-CDMA system. The newly designed searching finger has function of the searcher as well as the finger. The searching finger tests the PN code Phase as the searcher during the initial acquisition, and as the finger after the initial acquisition. The proposed system has reduced the average acquisition time of the PN codes to $T_{acq}$/19 in the 20MHz MC-CDMA system with 75% reduction of H/W complexity.y.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.252-257
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• 1995

Growth rates of the low temperature growing isolates, Pseudomonas fluorescens M45 and MC07, reached maximum stationary phase within 50 hrs at the low temperature, 4$^{\circ}C$. But an ordinary biocontrol agent P. putida Pf3 did not reach logarithmic growth phase until 80 hrs. The culture filtrates of M45 and MC07 significantly inhibited the mycelial growths of Pythium ultimum, Rhizoctonia solani and Phytophthora capsici. Detached cotyledons of cucumber grown on Murashige and Skoog agar medium were much enhanced in their growth, compared to those without the filtrates. Population densities of M45 and MC07 in the rhizosphere at 14$^{\circ}C$ were more stable than at 27$^{\circ}C$. When M45 and MC07 were treated into soil, the population density of MC07 continuously increased up to 9 days after treatment, and sustained the initial inoculum density up to 60 days. Cucumber damping-offs caused by P. ultimum and R. solani were significantly reduced by applying M45 as seed-inoculant and by soil treatment with MC07. The combined treatment of M45 and MC07 provided greater effect in reducing the disease incidence than that obtained by single treatments.

• International Journal of Oral Biology
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• v.30 no.2
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• pp.39-45
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• 2005

The present study was performed to investigate whether Achyranthes Radix extracts play roles in the bone metabolism. Three kinds of Achyranthes Radix extracts (methylene chloride (MC), ethylacetate (Ea), and water (W)) were used for bioassay. We examined cellular activities of osteoblasts by measurement of cell proliferation rate, alkaline phosphatase (ALP) activity, and calcified nodule formation. Osteoclast generation was assayed by measuring the number of tartrate-resistant acid phosphatase (TRAP) (+) multinucleated cells after culture of osteoclast precursor cells. There was a maximum 20% increase in proliferation rate of osteoblastic cells after treatment with MC. First and second subfraction of MC layer increased proliferation of osteoblast. Ea layer and second subfraction of MC layer increased ALP activity. Also MC layer and second subfraction of MC layer from Achyranthes Radix extracts increased the calcified nodule. MC layer and second subfraction of MC layer from Achyranthes Radix extracts significantly decreased in the number of TRAP (+) multinucleated cells. Taken together, Achyranthes Radix stimulates the proliferation and bioactivities of bone-forming osteoblasts, and inhibits activities of bone-resorbing osteoclasts.