• Title/Summary/Keyword: 2D:4D

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Estimating Carrying Capacity of Lake Shihwa for Water Quality Management (수질관리를 위한 시화호의 환경용량 산정)

  • Kim, Hyung-Chul;Choi, Woo-Jeung;Lee, Won-Chan;Koo, Jun-Ho;Lee, Pil-Yong;Park, Sung-Eun;Hong, Seok-Jin;Jang, Ju-Hyoung
    • Journal of Environmental Science International
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    • v.16 no.5
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    • pp.571-581
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    • 2007
  • The mechanism of water pollution in Lake Shihwa, one of highly eutrophicated artificial lakes in Korea, has been studied using a numerical 3D physical-biochemical coupled model. In this study, the model was applied to estimate the contribution of land-based pollutant load to water quality of heavily polluted Lake Shihwa. The chemical oxygen demand(COD) was adopted as an index of the lake water quality, and the spatial distribution of an average COD concentration during the summer from 1999 to 2000 was simulated by the model. The simulated COD showed a good agreement with the observed data. According to reproducibility of COD, the high-est levels between 8 and 9 mg/L were shown at the inner site of the lake with inflow of many rivers and ditches, while the lowest was found to be about 5 mg/L at the southwestern site near to dike gate. In the pre-diction of water quality of Lake Shihwa, COD showed still higher levels than 3 mg/L in case of reduction of 95% for land-based pollutant load. This suggests that the curtailment of land-based pollutant load is not only sufficient but the improvement of sediment quality or the increase of seawater exchange should be considered together to improve a water quality in Lake Shihwa.

Effect of Antihypertensive Peptides Originated from Various Marine Proteins on ACE Inhibitory Activity and Systolic Blood Pressure in Spontaneously Hypertensive Rats (어육단백질로부터 분리된 항고혈압 펩타이드가 ACE 저해활성과 본태성 고혈압쥐의 혈압에 미치는 영향)

  • Do, Jeong-Ryong;Heo, In-Sook;Jo, Jin-Ho;Kim, Dong-Su;Kim, Hyun-Ku;Kim, Seong-Su;Han, Chan-Ku
    • Korean Journal of Food Science and Technology
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    • v.38 no.4
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    • pp.567-570
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    • 2006
  • This study was carried out to investigate the effect of antihypertensive peptides originating from marine proteins on ACE inhibitory activity and systolic blood pressure in spontaneously hypertensive rats (SHR). Sixteen male SHR (SHR/NCrj) weighing approximately 270 g were randomly divided into few experimental groups based on diet: C (control), A (anchovy), P (pollack) and M (mackerel). The final body weights of P and M groups were higher, than those of C and A groups, but difference was not significant. Average reference blood pressure (RBP) was 224 mmHg at 12 weeks old. Compared with RBP, final systolic blood pressure of the marine peptide oops after 28 days of feeding with anchovy, pollack and mackerel fractions by gavage was decreased by 9.0% (A), 10.2% (P) and 14.3% (M), respectively, but was not different in C. Especially, final blood pressure of M was lower by 32 mmHg than RBP. These results suggested that peptide originated from mackerel hydrolysate was considered to have an antihypertensive fraction as effective lowering of blood pressure in SHR.

Phylogenetic Analysis based on Metallothionein Gene Sequence of an Indigenous Species Pisidium (Neopisidium) coreanum in Korea (한국 고유종 Pisidium (Neopisidium) coreanum (산골조개) 의 metallothionein 유전자를 기초로 한 분자계통 분류학적 연구)

  • Baek, Moon-Ki;Lee, Jun-Seo;Kang, Se-Won;Lee, Jae-Bong;Kang, Hyun-Jung;Jo, Yong-Hun;Noh, Mi-Young;Han, Yeon-Soo;Choi, Sang-Haeng;Chae, Sung-Hwa;Park, Hong-Seog;Lee, Jun-Sang;Lee, Yong-Seok
    • The Korean Journal of Malacology
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    • v.25 no.2
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    • pp.153-160
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    • 2009
  • Pisidium (Neopisidium) coreanum is a freshwater snail and lives in spring water near mountain areas. Interestingly, this snail has been traditionally regarded as medicinal food, and thus has been used as folk remedies for healing broken bones. Recently, alpha classification on Pisidium (Neopisidium) coreanum through redescription has been conducted. However, not much attention has been made in beta classification. In this study, we performed the beta classification based on metallothionein (MT) genes found from various organisms. To this end, the complete cDNA sequences were obtained from the Expressed Sequence Tag (EST) sequencing project of Pisidium (Neopisidium) coreanum. The coding region (315 bp) encoded an amino acid sequence of 105 residues. The combined results from BLAST analyses, multiple sequence alignment and molecular phylogenetic study of Pc-MT gene indicate that Pisidium (Neopisidium) coreanum has similarity to freshwater bivalve such as Dreissena polymorpha (zebra mussel), Unio tumidus (swollen river mussel) and Crassostrea ariakensis (suminoe oyster).

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A Clinical Study on the Hypercalcemia in Primary Bronchogenic Carcinoma (고칼슘혈증을 동반한 원발성 폐암의 임상적 특징)

  • Park, Hye-Jung;Shin, Kyeong-Cheol;Moon, Young-Chul;Chung, Jin-Hong;Lee, Kwan-Ho;Sung, Cha-Kyung;Lee, Hyun-Woo
    • Journal of Yeungnam Medical Science
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    • v.16 no.2
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    • pp.208-218
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    • 1999
  • Background: Lung cancer-associated hypercalcemia is one of the most disabling and life-threatening paraneoplastic disorders. Humoral hypercalcemia is responsible for most lung cancer-associated hypercalcemia. Patients with hypercalcemia are usually in the advanced stage with obvious bulky tumor and carry a poor prognosis. Materials and Methods: Total 29 patients satisfied the following criteria: histologically proven primary lung cancer, corrected calcium level ${\geq}$ 10.5 mg/dL, and symptoms which could possibly be attributed to hypercalcemia. In this retrospective study, we evaluated the various clinical aspects of hypercalcemia, in relation to cancer stage, histologic cell type, mass size, bone metastasis, performance status, and other possible characteristics. Results: Total 29 lung cancer patients with hypercalcemia were studied, and most of them had squamous cell carcinoma in their histologic finding. The incidence of hypercalcemia was significantly higher between 50 and 69 years of age, and in the advancement of cancer stage. Although serum calcium level showed positive correlation with mass size, performance status, and bone metastasis, it was not significant statistically. Altered consciousness was significantly more frequent in the patients with higher serum calcium level. There were no differences in effectiveness among therapeutic regimens. Hypercalcemia was more frequently in the later stage of disease than during the initial diagnosis of lung cancer. Most of the patients died within 1 month after development of hypercalcemia. Conclusion: We concluded that hypercalcemia in lung cancer is related to extremely poor prognosis, and may be one of the causes of death and should be treated aggressively to prevent sudden deterioration or death.

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A Study on the Characteristics according to Sasangin - Targeting the Group of Ordinary Adolescents - (사상인(四象人)의 성격(性格) 특성(特性)에 관(關)한 연구(硏究) -정상(正常) 청소년(靑少年) 집단(集團)을 대상(對象)으로 -)

  • Whang, Man-Ki;Hwang, Ui-Wan;Kim, Jong-Woo
    • Journal of Oriental Neuropsychiatry
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    • v.15 no.2
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    • pp.71-88
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    • 2004
  • Objectives : The aims of this report are to examine the personal characteristics and to determine the different reactions against stress by constitutions. To achieve these goals, the statistical research was adopted. Methods : First of all, the total numbers of 398 middle school students were classified into three constitutions by QSCC II. According to each type of constitutions, both of the KPI Personality Test and Multidimensional Encountering Scale (MES) on how to deal with stress were conducted. Summary of the findings : 1. Based on the findings assessed by the QSCC II test, the constitutional distribution reveals the difference according to genders. In Chi-square test, the girl reveals significantly high (p<0.05) distribution in Soyangin. 2. In Independent T-test regarding KPI personality, the girl reveals high significance (p<0.05) in terms of 'Sociability', 'Responsibility', 'Synchronism' and 'Self-feminity' (or Feminization) while the boy reveals high significance in 'Goal-driven' (p<0.05). 3. In Independent T-test regarding the multidimensional encounter scaling, the girl reveals high significance (p<0.05) in D (expression of emotion). 4. In case of the boy, the Soeumin shows low significance (p<0.05) in 'Leadership' and 'Sociability' compared to the Taeumin or the Soyangin. On the other hand, the Soeumin reveals high significance (p<0.05) in 'Responsibility' and 'Self-control' compared to the Soyangin and additionally, shows high significance (p<0.05) in 'Self-feminity' (or Feminization) compared to the Taeumin or the Soyangin. Furthermore, the Soyangin shows high significance (p<0.05) in 'Self-confidence' compared to the Soeumin or the Taeumin. 5. In case of the girl, the Soyangin reveals high significance in 'Sociability' and 'Self-confidence' compared to the Soeumin or the Taeumin while the Soeumin has high significance in 'Synchronism' compared to the Taeumin or Soyangin. On the other hand, the Soeumin has high significance in terms of 'Responsibility', 'Self-control', and 'Self-feminity' (or Feminization) while showing low significance in 'Flexibility' compared to the Soyangin. 6. For boys, the Soeumin has low significance in 'Sociability' in comparison with both the Soyangin and the Taeumin, whereas for girls, the Soyangin reveals high significance in 'Sociability' in comparison with both the Soeumin and the Taeumin. As per the 'Self-confidence' and 'Responsibility', it has been proved that there is no notable difference between the boy and the girl, but to the contrary, as per the 'Self-confidence', both for the girl and the boy, the Soyangin has high significance (p<0.05) in comparison with the Soeumin and the Taeumin. In addition, in 'Responsibility' side, it is recognized that the Soeumin shows high significance (p<0.05) in comparison with the Soyangin both for boys and girls. Only the difference between genders, as to the 'Self-confidence', is that the Soeumin shows low distribution compared to the Taeumin in the case of boys, while the Taeumin shows low distribution compared to the Soeumin in the case of girls. In 'Self-feminity' (or Feminization), for boys the Soeumin shows high significance in comparison with both the Soeumin and the Taeumin, but to the contrary, for girls the Soeumin shows high significance (p<0.05) only against the Soyangin. 7. In case of boys, as to 'Conformability (compromise)', the Taeumin compared to the Soeumin reveals high significance (p<0.05), while for girls, the Soeumin compared to the Soyangin or the Taeumin reveals high significance (p<0.05). Consequently, it presents that the Soyangin has a tendency not to confirm (compromise) relatively in comparison with other constitutions regardless of the genders. Conclusions : In general, except that it shows some constitutional deviation by genders, the statistical findings of this report agree and comply with the personal characteristics of Sasangin presented by Je-Ma Lee.

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Genetic Expression of Color Approved by Color Qualities of Munsell System on the Cocoon of Silkworm, Bombyx mori (누에 고치색 유전자 발현의 다양성 검정 및 색채과학적 해석)

  • Han, Myung-Sae;Park, Hyun-Ro;Han, Sang-Mi;Nam, Ki-Soo;Kwon, Soon-Ha;Lim, Jong-Sung;Nguyen, Mau Tuan
    • Journal of Sericultural and Entomological Science
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    • v.41 no.1
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    • pp.20-28
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    • 1999
  • Color qualities investigated on the basis of Munsell code and Korean standard color code for the cocoons from various strain of mulberry silkworm, Bombyx mori. 16 of different color qualities were identified from 21 of original silworm strains, and determinated international name with the revision of Korean color name for cocoon. The various cocoon color confirmed on the sphere from 567 to 593 nm wavelength, 78% of those located at the region about 580 nm (575~584) of sensitive "color difference limen". Y gene engaged broad ranges of wavelength (575~593 nm) in the color expression, by contrast with other genes of Pk (593 nm), F (584~593), Grc and relative G group (567~570 nm), on the transmission of carotenoid or flavonoid color substance. YC gene expression by original silk worm strain was also distinguished by those variation of specific yellow than other colors from Grc, GaGb, Gc, and YPkF. Appearance of chrome yellow cocoon was dominant than other yellow in the cross among vivid yellow group. F1 of pin${\times}$green produced the cocoon of yellow such as "additive mixture" as color light, however, most of the hybrid between yellow cocoon showed the color similar to "subtractive mixture" as a mixture of dyestuff. Hybrid cocoons among yellow or green colors were decreased their hue, value, and chroma, than those of parent. Diallel cross among the strain of various green cocoon suggest the existence of Grc, Ga, Gb, Gc genes. Cream colored cocoon of B. mandarina was differed from other yellow cocoon of Bobyx mori B. mori. Y$^A$ with Ymc showed the similar role of Y with C, therefore, segregated yellow cocoon from the B. mori${\times}$B. mandarina (+$^YC/Y^AYmc$). YC expression of $Y^AY$mc genes might be suppressed by deficiency of outer layer sericin on the middle division of silk giand in the B. mandarina.

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Corporate Bond Rating Using Various Multiclass Support Vector Machines (다양한 다분류 SVM을 적용한 기업채권평가)

  • Ahn, Hyun-Chul;Kim, Kyoung-Jae
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.157-178
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    • 2009
  • Corporate credit rating is a very important factor in the market for corporate debt. Information concerning corporate operations is often disseminated to market participants through the changes in credit ratings that are published by professional rating agencies, such as Standard and Poor's (S&P) and Moody's Investor Service. Since these agencies generally require a large fee for the service, and the periodically provided ratings sometimes do not reflect the default risk of the company at the time, it may be advantageous for bond-market participants to be able to classify credit ratings before the agencies actually publish them. As a result, it is very important for companies (especially, financial companies) to develop a proper model of credit rating. From a technical perspective, the credit rating constitutes a typical, multiclass, classification problem because rating agencies generally have ten or more categories of ratings. For example, S&P's ratings range from AAA for the highest-quality bonds to D for the lowest-quality bonds. The professional rating agencies emphasize the importance of analysts' subjective judgments in the determination of credit ratings. However, in practice, a mathematical model that uses the financial variables of companies plays an important role in determining credit ratings, since it is convenient to apply and cost efficient. These financial variables include the ratios that represent a company's leverage status, liquidity status, and profitability status. Several statistical and artificial intelligence (AI) techniques have been applied as tools for predicting credit ratings. Among them, artificial neural networks are most prevalent in the area of finance because of their broad applicability to many business problems and their preeminent ability to adapt. However, artificial neural networks also have many defects, including the difficulty in determining the values of the control parameters and the number of processing elements in the layer as well as the risk of over-fitting. Of late, because of their robustness and high accuracy, support vector machines (SVMs) have become popular as a solution for problems with generating accurate prediction. An SVM's solution may be globally optimal because SVMs seek to minimize structural risk. On the other hand, artificial neural network models may tend to find locally optimal solutions because they seek to minimize empirical risk. In addition, no parameters need to be tuned in SVMs, barring the upper bound for non-separable cases in linear SVMs. Since SVMs were originally devised for binary classification, however they are not intrinsically geared for multiclass classifications as in credit ratings. Thus, researchers have tried to extend the original SVM to multiclass classification. Hitherto, a variety of techniques to extend standard SVMs to multiclass SVMs (MSVMs) has been proposed in the literature Only a few types of MSVM are, however, tested using prior studies that apply MSVMs to credit ratings studies. In this study, we examined six different techniques of MSVMs: (1) One-Against-One, (2) One-Against-AIL (3) DAGSVM, (4) ECOC, (5) Method of Weston and Watkins, and (6) Method of Crammer and Singer. In addition, we examined the prediction accuracy of some modified version of conventional MSVM techniques. To find the most appropriate technique of MSVMs for corporate bond rating, we applied all the techniques of MSVMs to a real-world case of credit rating in Korea. The best application is in corporate bond rating, which is the most frequently studied area of credit rating for specific debt issues or other financial obligations. For our study the research data were collected from National Information and Credit Evaluation, Inc., a major bond-rating company in Korea. The data set is comprised of the bond-ratings for the year 2002 and various financial variables for 1,295 companies from the manufacturing industry in Korea. We compared the results of these techniques with one another, and with those of traditional methods for credit ratings, such as multiple discriminant analysis (MDA), multinomial logistic regression (MLOGIT), and artificial neural networks (ANNs). As a result, we found that DAGSVM with an ordered list was the best approach for the prediction of bond rating. In addition, we found that the modified version of ECOC approach can yield higher prediction accuracy for the cases showing clear patterns.

Triple Detector SPECT Imaging with $^{99m}Tc-DMSA$ in Adult Patients with Urinary Tract Infection (성인 요로 감염 환자에서 $^{99m}Tc-DMSA$ 삼중검출기 SPECT 영상의 유용성)

  • Ryu Jin-Sook;Bae, Won-Gyu;Moon Dae-Hyuk;Lee, Myung-Hae;Kim, Soon-Bae,;Park, Su-Kil;Park, Jung-Sik;Hong, Chang-Gi D.;Cho, Kyung-Sik
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.2
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    • pp.290-298
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    • 1992
  • Although early diagnosis of urinary tract infection is important, the radiologic evaluation is still controversial because of the low sensitivity and the lack of cost-effectiveness. This study was carried out to evaluate the clinical utility of high resolution triple head $^{99m}Tc-DMSA$ SPECT imaging in urinary tract infection. We prospectively performed $^{99m}Tc-DMSA$ planar and SPECT imaging, ultrasound of kidney (US), intravenous pyelography (IVP) and voiding cystourethrography (VCU) in all 60 adult patients with UTI [26 with first episode of acute pyelonephritis (APN), 22 with recurrent APN, and 12 persistent asymptomatic pyuria] and 25 normal persons. To assess reversibility of the renal cortical defect (RCD), $^{99m}Tc-DMSA$ SPECT was repeated 1 to 8 months later in those patients with abnormal initial findings. Overall detection rate of $^{99m}Tc-DMSA$ SPECT imaging was 83% (50/60), but planar, US, IVP and VCU showed abnormal findings in 68%, 28%, 32% and 13%, respectively. 25 out of 27 patients with normal or single RCD were all normal in other radioligic studies. Only two patients showed vesicoureteral reflux (VUR) on VCU (grade I) and mild hydronephrosis on IVP. But, high proportion of those with multiple RCD showed abnormal findings on US (17/33), IVP (18/33), and VCU (7/33): 67% in any of these 3 studies. Especially, 3 out 7 patients with VUR showed multiple RCD on $^{99m}Tc-DMSA$ SPECT without any abnormality on IVP or US. 25 normal persons showed normal findings in all studies except one false positive finding on $^{99m}Tc-DMSA$ SPECT imaging. Follow-up $^{99m}Tc-DMSA$ SPECT was done in 28 patients (13 with single RCD, 15 with multiple RCD). All 13 patients with single RCD showed improvement. Those with multiple RCD presented improvement in 4, no change in 10, and aggravation in 1 on follow-up studies. With these results, we conclude: 1) $^{99m}Tc-DMSA$ SPECT imaging is superior to planar imaging, US, IVP or VCU in detection of renal lesion in urinary tract infection. $^{99m}Tc-DMSA$ SPECT is useful as a initial diagnostic tool in adult patients with urinary tract infection. 2) The multiple RCD on $^{99m}Tc-DMSA$ SPECT represent the high probability of irreversible tissue change and need of extensive urological work-up.

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Half a cenury of the rural geography in Korea(1945-1995):review and prospect (촌락지리학 50년(1945-1995)의 회고와 전망)

  • ;Lee, Moon-Jong
    • Journal of the Korean Geographical Society
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    • v.31 no.2
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    • pp.213-254
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    • 1996
  • The Korean Geographical Society was founded in 1945, when Korea was liberated from the Japanese rule. And The Journal of the Korean Geography activated academic studies of geography by publishing research papers in it. Professor Kang, Dae-Hyun wrote the first two specialized papers of rural geography in 1966: " Flood Plain Settlements on the Han River" and "The Location and Form of the Dispersed Villages around Dae-Cwan-Ryung". The early studies of rural geography were not based on serious academic foundations, such as the adjustment of theoretical notions and a good grasp of subjects. After choosing subjects that came to hand without academic consideration. they simply enumerated generalized items of the results of the field work investigation such as the location the landscape and the process of formation of the settlements. In the 1970s and 1980s, however, rural settlement studies progressed remarkably in Korea. More than 80% of 318 dissertations, theses, or papers collected for this review were written in the late 1980s, and the subjects and methodology became diversified. As may be expected, recent studies are found very systematic and problem-solving in the various fields - contexual understanding spatial structure, the development of clan villages according to the socialization process, the effects of rural-out migration on the change of villages etc. Such a trend can be understood as a reaction to the circumstances under which, as the Western society already experienced, rural villages become washed out by the waves of industralization and urbanization and hardly continue to exist. In this paper, geographical studies of rural settlement which have been carried out in Korea last fifty years will be reviewed under the four headings on the studies related to a) farming villages; b) fishing villages; c) mountain villages: and d) special function villages. Studies of farming villages and related ones are very diverse. The results of the studies carried out last fifty years can be classified into sixteen subjects. Just as, in the West, studies of rural settlement have been mainly concerned with farming villages since rural geography came into being, so, in Korea, they have been centred on farming villages. It is a natural result considering the history of human life. Even in Korea, however the rural settlement is no more an isolated life space which keeps unique traditions of old life style, but it begins to form a dynamic life space connected to big cities by heavy traffic. Because the modern farming villages of Korea have an undetachable connection with the cities, special methodology to solve new problems has been posed in the studies of rural settlement. Many scholars have produced a lot of studies of farming villages, and three of them are prominent: Oh. Hong-Seok, Choi, Ki-Yeop, and Lee, Moon-Jong. Oh, Hong-Seok is a versatile and hard-working scholar who has published more papers than anyone else in the various fields of rural geography such as farming villages, fishing villages, mountain villages, and reclamation villages. And he has expanded his concerns to environment issues in recent years. Choi, Ki-Yeop has maintained that the prototype of Korean rural villages is clan villages continuing to write a series of good papers in which he pursues their regionalizion in the process of socialization. Lee, Moon-Jong divides the spatial organization of side settlement, sahachon (settlement near the temple), religion settlement, orchard settlement, settlement near the foreign military camp, displaced people's settlement. Chung Gam Lok settlement, etc. Though The Korean Geographical Society has half a century's history, academic activties in the field of rural settlement have been performed no more than thirty years. We cannot help saying that it is admirable that in such a rather short time we have five academical schools of the rural geography in Korea. geography in Korea.

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Induction of Apoptosis by Piceatannol in YD-15 Human Oral Cancer Cells (피세아타놀에 의한 YD-15 구강암세포의 세포자가사멸 유도 효과)

  • Lee, Hae-Nim;Jang, Hye-Yeon;Kim, Hyeong-Jin;Shin, Seong-Ah;Choo, Gang-Sik;Park, Byung-Kwon;Kim, Byeong-Soo;Jung, Ji-Youn
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.7
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    • pp.975-982
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    • 2015
  • Piceatannol (trans-3,4,3',5'-trihydroxystilbene), a natural stilbene, is an analogue of resveratrol. In the present study, possible mechanisms by which piceatannol exerts its pro-apoptotic action in cultured human oral cancer YD-15 cells were investigated. To investigate whether or not piceatannol has effects on cancer cell viability, human oral YD-15 cells were treated with piceatannol (0, 50, and $100{\mu}M$). Piceatannol treatment ($100{\mu}M$) showed the strongest inhibition of cell proliferation and reduced cell viability in a dose-dependent manner. Chromatin condensation detected by DAPI staining significantly increased in a concentration-dependent manner, indicating apoptosis. Piceatannol treatment activated initiator Bax (pro-apoptotic) and cPARP in a concentration-dependent manner. Further, piceatannol induced down-regulation of Bcl-2 (anti-apoptotic). We also evaluated the activity of piceatannol against oral cavity cancer tumors in mice. Piceatannol-treated nude mice bearing YD-15 xenograft tumors exhibited significantly reduced tumor volume and weight due to the potent effect of piceatannol on tumor cell apoptosis, as determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Immunohistochemistry staining showed elevated expression of cleaved-caspase-3 as well as reduced expression of Ki-67 in the piceatannol-treated group. Therefore, piceatannol can be developed as a cancer preventive medicine due to its growth inhibitory effects and induction of apoptosis in human oral cancer cells.