• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1776-1783
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• 2002

A population segregating for the naked neck (Na) gene was used to evaluate its effect on fast growing broilers at heat stress. An experimental stock comparable to those of modern broilers was established by backcrossing to colour synthetic male and female lines. Matings between heterozygous (Na/na) males and females produced normally feathered (na/na), heterozygous (Na/na) and homozygous (Na/Na) chicks for the present study. Day old to seven week old coloured broilers of three genotypes viz. normally feathered (na/na), heterozygous naked neck (Na/na) and homozygous naked neck (Na/Na) were compared for heat dissipation, growth performance, body conformation traits, blood biochemical parameters and carcass traits in tropical climate. In hot climate, naked neck broilers had significantly less body temperature and better heat dissipation capabilities as compared to normal broilers. The naked neck broilers had significantly higher body weight and better feed conversion ratio than na/na broilers. The Na/Na or Na/na broilers exhibited higher giblet yield, blood loss and lower feather mass compared to na/na broilers. The results indicated that the reduction in feather coverage in Na/Na and Na/na broilers facilitates better heat dissipation with lower body temperature, more body weight gain, better FCR and carcass traits compared to normal broilers.

• Journal of Forest and Environmental Science
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• v.32 no.3
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• pp.311-322
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• 2016

Since forest trees form the basis of forest ecosystem, their prolong subsistence is crucial for various flora and fauna. The foremost challenges to sustain the forest ecosystem comprise of the declining forest tree population accompanied with structural changes due to afforestation and exploitation of forest area, environment changes, pests, pollution, and introgressive hybridization. For ex situ conservation approach, in vitro techniques encompass basic role for conserving tree genetic resources, predominantly where natural propagules like recalcitrant seed might not be appropriate for long-term conservation. The practice includes restricted growth techniques, conventional micropropagation, production and storage of synthetic seeds, and cryopreservation. Even though these practices have been applied chiefly to herbaceous species, but recently, woody species were also focused upon. Key conceptions, challenges and techniques for forest tree seed conservation are discussed briefly in this review with special emphasis on some successful cryopreservation approaches for long-term storage.

• The Korean Journal of Applied Statistics
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• v.18 no.3
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• pp.627-637
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• 2005

Small area estimation has been studied using various methods such as direct, indirect, synthetic and based on regression or time series model . In this paper we investigate a motel-based small area estimation which takes into account the spare time autoregressive model. The Economic Active Population Surveys in 2001 are used for analysis and the results from space-time autoregressive(STAR) and simultaneous autoregressive(SAR) model are compared with using MSE, MAE and MB.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.2
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• pp.163-171
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• 2014

Epidemic models are used to analyze the spreading of epidemic diseases, estimate public health needs, and assess the effectiveness of mitigation strategies. Modeling scope of an epidemic model ranges from the regional scale to national and global scale. Most of the epidemic models developed in Korea are at the national scale using the equation-based model. While these models are useful for designing and evaluating national public health policies, they do not provide sufficient details. As an alternative, individual-based models at the regional scale are often used to describe disease spreading, so that various mitigation strategies can be designed and tested. This paper presents an individual-based epidemic spreading model at regional scale. This model incorporates 2005 census data to build the synthetic population in the model representing Daejeon in 2005. The model's capability is demonstrated by an example where we assess the effectiveness of several mitigation strategies using the model.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.277-279
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• 2003

The study utilizes remote sensing as the main monitoring means. With different spatial high-resolution, multichannel ASTER remote sensing image as the main information in Beijing city zone; with regional border and statistical data as auxiliary factor a study between the thermal space distribution character and the underground medium is analyzed based on the GIS logical algorithm and synthetic analysis technology. Results show thermal forming mechanism and the rule of distribution is mainly related to the underground medium and the change of the city distribution. Different underground medium has different degree and intensity influence on the thermal space distribution. Furthermore, urban greenbelt and water areas can reduce the thermal effect and large-scale greenbelt creates green island effect. In addition, Road net, residential area, population density, heat resources and so on have some positive effect on the thermal distribution, which increase the local temperature and intensity on the other hand. It is important to study the thermal distribution and its related factors, which contributes to the plan, construction and development of the city.

• Biomolecules & Therapeutics
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• v.30 no.6
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• pp.576-584
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• 2022

Colorectal cancer is diagnosed as the third most prevalent cancer; thus, effective therapeutic agents are urgently required. In this study, we synthesized six homoisoflavane derivatives of cremastranone and investigated their cytotoxic effects on the human colorectal cancer cell lines HCT116 and LoVo. We further examined the related mechanisms of action using two of the potent compounds, SH-19027 and SHA-035. They substantially reduced the cell viability and proliferation in a dose-dependent manner. Treatment with SH-19027 and SHA-035 induced cell cycle arrest at the G2/M phase and increased expression of p21 both of which are implicated in cell cycle control. In addition, the apoptotic cell population and apoptosis-associated marker expression were accordingly increased. These results suggest that the synthesized cremastranone derivatives have anticancer effects through the suppression of cell proliferation and induction of apoptosis. Therefore, the synthesized cremastranone derivatives could be applied as novel therapeutic agents against colorectal cancer.

• Journal of Korean Academy of Nursing
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• v.52 no.2
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• pp.144-156
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• 2022

Purpose: This study aimed to investigate the influence of social capital on the depression of older adults living in rural areas. Methods: Data sets were obtained from the 2019 Korea Community Health Survey. The participants were 39,390 older adults over 65 years old living in rural areas. Indicators of social capital included trust, reciprocity, network, and social participation. Depression-the dependent variable-was measured using the Patient Health Questionnaire-9 (PHQ-9). Hierarchical ordinal logistic regression was conducted to identify factors associated with depression after adjusting the data numbers to 102,601 by applying the Synthetic Minority Oversampling Technique (SMOTE). Results: The independent variables-indicators of social capital-exhibited significant association with the depression of older adults. The odds ratios of depression were higher in groups without social capital variables. Conclusion: To reduce depression, we recommend increasing social capital. Factors identified in this study need to be considered in older adult depression intervention programs and policies.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.888-901
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• 2020

Objective: A set of microsatellite markers with high polymorphism from Tsaiya duck were used for the genetic monitoring and genetic structure analysis of Brown and White Tsaiya duck populations in Taiwan. Methods: The synthetic short tandem repeated probes were used to isolate new microsatellite markers from the genomic DNA of Tsaiya ducks. Eight populations, a total of 566 samples, sourced from Ilan Branch, Livestock Research Institute were genotyped through novel and known markers. The population genetic variables were calculated using optional programs in order to describe and monitor the genetic variability and the genetic structures of these Tsaiya duck populations. Results: In total 24 primer pairs, including 17 novel microsatellite loci from this study and seven previously known loci, were constructed for the detection of genetic variations in duck populations. The average values for the allele number, the effective number of alleles, the observed heterozygosity, the expected heterozygosity, and the polymorphism information content were 11.29, 5.370, 0.591, 0.746, and 0.708, respectively. The results of analysis of molecular variance and principal component analysis indicated a contracting Brown Tsaiya duck cluster and a spreading White Tsaiya duck cluster. The Brown Tsaiya ducks and the White Tsaiya ducks with Pekin ducks were just split to six clusters and three clusters when K was set equal to 6 and 3 in the Bayesian cluster analysis. The individual phylogenetic tree revealed eight taxa, and each individual was assigned to its own population. Conclusion: According to our study, the 24 novel microsatellite markers exhibited a high capacity to analyze relationships of inter- and intra-population in those populations with a relatively limited degree of genetic diversity. We suggest that duck farms in Taiwan could use the new (novel) microsatellite set to monitor the genetic characteristics and structures of their Tsaiya duck populations at various intervals in order to ensure quality breeding and conservation strategies.

• The Korean Journal of Zoology
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• v.33 no.4
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• pp.435-445
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• 1990

Gonadotropin releasing horrnone (GnRH) is known to be extrahypothalamically localized with a broad range including gonad. It remains, however, unknown whether GnRH is locally synthesized in the gonad. The present srudy aims to identity expression and cellular localization of GnRH-Iike mRNA and immunoreactive GnRH in the rat gonad. GnRH radioimmunoassay and chromatographic extracts on G-50 sephadex column showed that rat gonadal extracts contained a substantial amount of immunoreactive GnRH similar to the hypothalamic and synthetic GnRH. Although a wide distribution of immunostainable GnRH-like molecule with different cell types in the rat ovary was observed, the major cell population hybridized with GnRH probe appears to be granulosa. theca cells and corpus luteum. Immunoreactive GnRH-Iike peptides were distributed m various regions of testis, including spermatogenic cells, Sertoli cells and Leydig cells. In situ hybridization revealed that positive signals of GnRH-Iike mRNA were predominandy present in Sertoli cells within some seminiferous tubules, but absent in the outside of seminiferous tubules in the testis. This study clearly demonstrated that GnRH-Iike molecule present in the rat gonad may be resulted from the local synthetic machinery of GnRH supporting the notion that this peptide may act as autocrine and/or paracrine role in intra-gonadal communication.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.617-622
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• 2018

Air is essential for human beings to survive, but urban air is polluted with soot and harmful gases, due to the increase in industrial development and the population. Thus, air pollution in large cities is of increasing interest in the research community. One of the plausible solutions to this problem is supplying sufficient oxygen to indoor spaces. The main principle of the oxygen generator is to separate oxygen from air using synthetic zeolite. Various synthetic zeolites have been applied to public indoor spaces with the focus being placed on the oxygen exchange quality. Among the characteristics of zeolites which can be applied to oxygen generators is their ability to adsorb nitrogen from the air and, in this way, generate only oxygen. Thus, we investigated the degree of nitrogen adsorption by five kinds of natural zeolite and LTA zeolite 3A, 4A, and 5A (two different sizes). Using the PSA method, the higher the degree of nitrogen adsorption, the higher the oxygen saturation concentration, it was found that the nitrogen adsorption degree of the 5A zeolite was the highest. 6% on average. It was also found that the size of the zeolite had a significant effect on the degree of nitrogen adsorption.