• Journal of Life Science
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• v.28 no.6
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• pp.745-752
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• 2018

Melanogenesis is involved in the pigmentation of the hair, eyes, and skin in living organisms. Various signaling pathways stimulated by ${\alpha}-MSH$, SCF/c-Kit, $Wnt/{\beta}-catenin$, nitric oxide and ultraviolet activate melanocyte, leading to melanin production by tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 expressed via the microphthalmia-associated transcription factor (MITF). However, the abnormal regulation of melanogenesis causes dermatological issues such as graying hair and vitiligo. Therefore, the activators that promote melanogenesis are crucial for the prevention of graying hair and the treatment of hypopigmentary disorders. Many melanogenesis stimulators have been studied for the development of novel drugs derived from synthesized compounds and natural products. Here, in addition to providing a description of a common signaling pathway in the melanogenesis of graying hair and the vitiligo process for the development of novel anti-hair graying agents, this article reviews natural herbs and the active ingredients that promote melanin synthesis as a pharmaceutical agent for the treatment of vitiligo. In particular, compounds such as Imatinib and Sugen with a stimulating effect on melanogenesis as a side effect of the drugs, are also introduced. Recent advances in research on natural plant extracts such as Polygonum multiflorum, Rhynchosia Nulubilis, Black oryzasativa, and Orysa sartiva, widely known as traditional and medicinal extracts, are also reviewed.

• Korean Journal of Biological Psychiatry
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• v.8 no.1
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• pp.20-36
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• 2001

The debate about whether depressive disorders should be divided into categories or arrayed along a continuum has gone for decade, without resolution. In our review, there is more evidence consistent with the spectrum concept than there is with the idea that depressive disorders constitute discrete clusters marked by relatively discontinuous boundaries. First, "depression spectrum", "is there a common genetic factors in bipolar and unipolar affective disorder", "threshold model of depression" and "bipolar spectrum disorder" are reviewed. And, a new subtype of depression is so called SeCA depression that is a stressor-precipitated, cortisol-induced, serotonin-related, anxiety/aggression-driven depression. SeCA depression is discussed. But, there is with the idea that depressive disorders constitute discrete subtypes marked by relatively discontinuous boundaries. This subtypes of depressive disorder were reviewed from a variety of theoretical frames of reference. The following issues are discussed ; Dexamethasone suppression test(DST), TRH stimulation test, MHPG, Temperament Character Inventory(TCI), and heart rate variability(HRV).

• Applied Biological Chemistry
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• v.36 no.6
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• pp.547-552
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• 1993

Soybean nuclear extracts and S-100 were prepared to examine the soybean embryo factors which bind to the upstream region of soybean ${\beta}-conglycinin$ ${\alpha}'$ subunit gene. SEF3(soybean embryo factor 3), which is presumed to be a trans-acting factor for the expression of the gene, was detected in gel mobility shift assay using the DNA probe containing two AACCCA hexanucleotides. DNA probe containing CATGCAT or AACACA was used to find any other soybean embryo factor interacting with the upstream region of ${\beta}-Conglycinin$ ${\alpha}'$ subunit gene. It was found that there was no common DNA binding protein detected both in nuclear extracts and S-100. The relative levels of SEF3 binding activity both in nuclear extracts and S-100 of maturing soybean seeds were determined. SEF3 activity of nuclear extracts was first detected around 20 days after pollination and significantly increased around 32 days after pollination.

• Archives of design research
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• v.20 no.1 s.69
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• pp.143-154
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• 2007

The purpose of this study is to investigate fashion product image evaluation according to life-style groups of middle-aged women. The subject of investigation was 352 middle-aged women from 35 to 59 living in Daegu by random sampling method in April and May, 2005. The investigation was carried out by questionnaires which were composed of 3 sections: Fashion product image measure, Life style research and demographic variables(age, academic background, occupation, monthly clothing allowance, monthly income). The statistical methods to analyze the data were frequency, percentage, average, factor analysis, cluster analysis, ANOVA, Duncan's multiple range test. The results are summarized as follows: 1. As a result of factor analysis for fashion product image, the four factors including noble image, bold image, practical image, female image were extracted. 2. Middle-aged women were classified into four life-style groups including tradition oriented group, negative oriented group, activity oriented group and appearance oriented group. 3. Significant differences in fashion product image preferences according to life-style groups were found. Tradition oriented group preferred noble image and practical image. Negative oriented group tended to pursue practical image. Activity oriented group pursued a bold image. Appearance oriented group liked a noble image the best and then noble image, bold image in order.

• Journal of the Korean association of regional geographers
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• v.1 no.1
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• pp.1-21
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• 1995

We Korean geographers have been interesting merely in research trends and models which induced in more advanced societies. We unconcerned with the models were painfully acquired through many field surveys and accumulated researches. Approaches to the generalization without accumulating experienced studies are just like 'building on the sand' and 'it is nothing but the paper'. We still need many field surveys, regional approaches and very basic researches for induced the Korean geographic models. In geography. 'where' is not main goal. 'Why and how' are the most important. We know these very much. But we do not recognize that 'what is where' in Korea, still now. We must have our own Korean spatial models. But geography is not build in a day and in one generation. It needs interdisciplinary or system approaches accompany with the other fields of sciences. We concern with the spatial principles and laws which were hidden by the complicated phenomena in real world.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.563-580
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• 2010

In 2009 the Korea Ministry of Environment announced 'A Comprehensive Plan for the Improvement of Sewer Service in Rural Area' aiming at reduction of the sewer service gap between urban and rural areas as well as improvement in the residential environment of the rural area. According to the plan, the sewer system supply rate for the rural area is expected to reach up to 75% until 2015 with the budget of 4.7 trillion won (Korean currency). It is not certain, however, that the increase in the sewer system supply rate will accompany improvement of water quality in receiving water because several veiled problems that can occur in small-scale sewer treatment plants are poorly addressed in the plan. In this study, those issues for the small-scale sewer treatment plants and their solutions were discussed based on a case study in which we investigated 19 treatment facilities at two rural regions in Gyeonggi province. This study also included strategies useful for the plan. From the results of investigation, some problems, e.g., high hourly variations but low in flowrates and low mass loading were commonly identified. Although operation parameters in sewer treatment plants require to be modified depending on the mass loading, most of the plants were operated with the initial design parameters which causes the decrease of removal efficiency. In the intensive diagnosis, we arranged and applied solutions (e.g., flow equalization, air on/off time control, etc) to the two selected plants and found out improvement of effluent water quality, especially organic matters (COD and SS) and T-N with better denitrification performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.218-225
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• 2016

Recently, Korea has undergone rapid social and economic development, and with that came various changes in living habits and disease patterns; the nation, accordingly, has been alerted to the associated risks of chronic ailments. As risk factors of metabolic syndrome commonly include causal factors of chronic diseases, prevention is important. The prevalence of metabolic syndrome in Korean adults is 22.4%, which comprises a large portion of the whole disease (Korean National Health and Nutrition Examination Survey, 2013). This study aims to examine the elements of healthy living practices by analyzing the risk factors of metabolic syndrome and health behaviors, and provide basic materials to contribute to the activation of health promotion. Among 12,481 subjects of the source data from the 2014 community health survey, which was performed on adults aged 19 and over in Jeonlabuk-do, 12,185 people were analyzed in this study using SPSS 23.0. There were significant differences with respect to sex, smoking status, age, education level, and number of days of physical activity among the results of the difference of the risk factors of the metabolic syndrome according to the characteristics of the health behavior of the subjects. Of the risk factors for metabolic syndrome, this study emphasized the necessity of strategies to promote health programs regarding the management of drinking, smoking, physical activities, depression, subjective health condition and quality of life to the group of those with dyslipidemia, hypertension, and diabetes.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.79-86
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• 2012

ErmSF is one of the Erm family proteins which catalyze S-adenosyl-$_L$-methionine dependent modification of a specific adenine residue (A2058, E. coli numbering) in bacterial 23S rRNA, thereby conferring resistance to clinically important macrolide, lincosamide and streptogramin B ($MLS_B$) antibiotics. $^{222}FXPXPXVXS^{230}$ (ErmSF numbering) sequence appears to be a consensus sequence among the Erm family. This sequence was supposed to be involved in direct interaction with the target adenine from the structural studies of Erm protein ErmC'. But in DNA methyltarnsferase M. Taq I, this interaction have been identified biochemically and from the complex structure with substrate. Arginine 223 and 227 in this sequence are not conserved among Erm proteins, but because of the basic nature of residues, it was expected to interact with RNA substrates. Two amino acid residues were replaced with Ala by site-directed mutagenesis. Two mutant proteins still maintained its activity in vivo and resistant to the antibiotic erythromycin. Compared to the wild-type ErmSF, R223A and R227A proteins retained about 50% and 88% of activity in vitro, respectively. Even though those arginine residues are not essential in the catalytic step, with their positive charge they may play an important role for RNA binding.

• The Journal of the Acoustical Society of Korea
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• v.7 no.4
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• pp.54-76
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• 1988

In Part Ⅰ of the paper, we have developed various block least mean-square (BLMS) adaptive digital filters (ADF's) based on a unified matrix treatment. In Part Ⅱ we analyze the convergence behaviors of the self-orthogonalizing frequency-domain BLMS (FBLMS) ADF and the unconstrained FBLMS (UFBLMS) ADF both for the overlap-save and overlap-add sectioning methods. We first show that, unlike the FBLMS ADF with a constant convergence factor, the convergence behavior of the self-orthogonalizing FBLMS ADF is governed by the same autocorrelation matrix as that of the UFBLMS ADF. We then show that the optimum solution of the UFBLMS ADF is the same as that of the constrained FBLMS ADF when the filter length is sufficiently long. The mean of the weight vector of the UFBLMS ADF is also shown to converge to the optimum Wiener weight vector under a proper condition. However, the steady-state mean-squared error(MSE) of the UFBLMS ADF turns out to be slightly worse than that of the constrained algorithm if the same convergence constant is used in both cases. On the other hand, when the filter length is not sufficiently long, while the constrained FBLMS ADF yields poor performance, the performance of the UFBLMS ADF can be improved to some extent by utilizing its extended filter-length capability. As for the self-orthogonalizing FBLMS ADF, we study how we can approximate the autocorrelation matrix by a diagonal matrix in the frequency domain. We also analyze the steady-state MSE's of the self-orthogonalizing FBLMS ADF's with and without the constant. Finally, we present various simulation results to verify our analytical results.

• KDI Journal of Economic Policy
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• v.26 no.2
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• pp.3-62
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• 2004

This paper estimates Korea's natural rate of unemployment using various estimation methods such as pure time-series methods, reduced-form methods, and structural form methods, with discussion about relative advantages and disadvantages of each estimation method. This paper also provides the confidence interval of the estimated natural rate of unemployment by the Monte Carlo integration method. Though multivariate unobserved component model exhibits better performance in many aspects than other estimation methods, awareness should be raised for a potential misspecification problem of a multivariate unobserved component model. Considering that each method has its own advantages and disadvantages, it is recommended to make an inference on the natural rate of unemployment based on common results among various methods. Korea's natural rate of unemployment was estimated to be around 3.8~4.0% on average in the period of 1979:I~1987:IV, and to decline to 2.5~2.9% in the period of 1988:I~1997:IV. During the Asian crisis, it is estimated to peak at near 4.8% and to have been on a downward trend since then.