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Sampling and Cryogenic Pulverization and Storage of Environmental Samples and Improvement of Operating Procedures in National Environmental Specimen Bank (국가환경시료은행 시료 채취, 분쇄, 저장과 개선방안 고찰)

  • Lee, Jangho;Lee, Jongchun;Kim, Myungjin;Han, Areum;Lee, Eugene;Bade, Rabindra;Kim, Minsung
    • Journal of Environmental Impact Assessment
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    • v.21 no.6
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    • pp.823-839
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    • 2012
  • Environmental Specimen Banks (ESBs) are playing pivotal role in monitoring the effect of environmental pollution on the ecosystem based on the retrospective analysis of the representative samples collected regularly and stored in cryogenic condition. In Korea, National Environmental Specimen Bank (NESB) was established in 2009 and the standard operating procedures (SOPs) for sampling, and cryogenic milling and storage had been prepared during 2007-2010. Since then, the tentative SOPs for the seven kinds of specimens (shoots of Red Pine (Pinus densiflora) and Korean Pine (Pinus koraiensis), leaves of Mongolian Oak (Quercus mongolica) and Zelkova Tree (Zelkova serrata), eggs of Feral Pigeon (Columba livia var. domestica), muscles and organs of Common Carp (Cyprinus carpio), and Freshwater Bivalve (Unio (Nodularia) douglasiae)) have been put to test in the field and laboratory as well against the practicality and feasibility. The SOPs were improved by reflecting the findings from the research and the following discussion regarding the selection of specimen (Feral Pigeon suffering from a control management), sample size (a problem of decreasing number of sampling trees related to increasing sampling time) and period (a problem related to a bud growth), and sampling methods etc.. In addition, barcoding system for the management of the specimen information, and monitoring system of the cryogenic storage to regulate the optimum temperature and the liquid nitrogen level were also developed for the efficient and effective control of the samples. Lastly, the safety guide and emergency protocol were augmented to guarantee a safe work environment with the cryogenic facility. These improvements of the SOPs are expected to contribute to more stable operation of the NESB.

Analysis of Spatial Variability for Infiltration Rate of Field Soil -I. Variogram (토양(土壤)중 물의 침투속도(浸透速度)의 공간변이성(空間變異性) 분석(分析) -I. Variogram)

  • Park, Chang-Seo;Kim, Jai-Joung;Cho, Seong-Jin
    • Korean Journal of Soil Science and Fertilizer
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    • v.16 no.4
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    • pp.305-310
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    • 1983
  • Spatial variability of infiltration rates of 96 samples from Hwadong SiCL was studied by using geostatistical concepts. The measurement was made at the nodes of the regular grid consisting of 12 rows and 8 columns. Sample spacing within rows and columns was 3 and 2 meters, respectively. This study illustrated the use of variogram as a tool to identify the degree of dependency of the infiltration rate on the distance between pairs of measurements and how to take advantage of this dependency. Fractile diagram showed that the distribution of observation was approximately normal. The range of the variogram was about 7.4 meters. The minimum number of samples necessary to reproduce the results similar to the 96 measured values was 8 to 10. Coefficients of theoretical variogram function for computing kriged values and kriged varionces of nuogget effect, slope, and range were 0.444 cm/day, 0.003 cm/day, and 7.4 m, respectively.

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Mobi-kids: A Case-control Study Protocol on Electromagnetic Field Radiation Exposure from Telecommunication and Brain Tumors in Children and Adolescents (모비키즈: 통신전자파 노출과 어린이청소년의 뇌종양에 관한 환자 -대조군 연구 프로토콜)

  • Choi, Kyung-Hwa;Kim, Dong-Seok;Lee, Jung-il;Ra, Young-Shin;Phi, Ji Hoon;Ahn, Young Hwan;Kwon, Jong Hwa;Lee, Ae-Kyoung;Choi, Hyung-Do;Ha, Mina
    • Journal of Environmental Health Sciences
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    • v.41 no.3
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    • pp.182-190
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    • 2015
  • Objectives: To introduce a protocol of Mobi-kids study which was aimed to examine an association between radiofrequency (RF) radiation exposure by mobile phone use and brain tumor risk in children and adolescents. Methods: The Mobi-kids study was a multinational matched case control study using a standardized protocol with the number of subjects targeted about 1,000 cases and 2,000 controls aged 10 to 24. In Mobi-Kids Korea, the source population was restricted to Seoul, Incheon, and Gyeonggi-do province. Eligible cases of primary brain tumor (glioma, meningioma, and others) were diagnosed from January 2012 to June 2015. Eligible controls were appendicitis patients operated during the study period. Two controls were matched on age, gender, and study region for 1 case. Information about pattern and history of mobile phone use and other covariates were obtained by face to face interview by trained interviewer. The Mobi-kids study has been involved in Mobi-expo as a validation study about mobile phone use, XGridmaster to localize tumor in the brain for RF energy calculation, and histological review for validation of diagnosis. Results: The Mobi-kids was the first and largest study in children and adolescents to estimate risk of brain tumor in association with the RF energy absorption in the brain estimated by mobile phone use. Forty-six-cases and 54 controls were collected as of September 2014 in Korea. Conclusions: The meaningful results of the study were expected because of the largest sample size, high validity of EMF exposure assessment as well as the susceptible study populationof children and adolescents.

Validity Assessment of Self-reported Smoking Status: Results from the Korean National Environmental Health Survey (KoNEHS) 2009-2011 (흡연상태에 관한 자가보고 설문의 타당도 평가: 제1기(2009-2011) 국민환경보건기초조사 자료 분석)

  • Choi, Wookhee;Park, Kyung Hwa;Kim, Hyun Jeong;Ryu, Jungmin;Yu, Seung Do;Choi, Kyunghee;Kim, Suejin
    • Journal of Environmental Health Sciences
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    • v.40 no.6
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    • pp.492-501
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    • 2014
  • Objectives: The purpose of this study was to assess the validity of self-reported cigarette smoking status and investigate factors associated with the accuracy self-reported and measured urinary cotinine in Korean adults. Methods: We used data from the $1^{st}$ Korean National Environmental Health Survey (2009-2011) among adults aged ${\geq}19$ years (N=6,246). The survey examined self-reported smoking status, and urinary cotinine was regarded as the biomarker of exposure to tobacco smoke. Urinary cotinine was analyzed using a gas chromatography-mass spectrometry (GC/MS) and data analysis was conducted using IBM SPSS version 20.0, which uses the sample weight and calculates variance estimates to adjust for the unequal probability of selection into the survey. Results: We calculated a cut-off point (53.3 ug/L) by using a ROC (Receiver Operating Characteristic) curve. The smoking prevalence was 24.6% based on self-reported data and 28.2% based on urinary cotinine concentrations. When we assessed the agreement between self-reported and urinary cotinine, we found an average agreement of 97.7% among self-reported smokers and 94.5% among self-reported non-smokers. Among self-reported smokers, factors affected the discrepancy were age, household economic status and average number of cigarettes smoked per day. On the other hand, gender, former smoking experience, and exposure to SHS (second hand smoke) were associated with discrepancies among self-reported non-smokers. Conclusion: These results suggest that self-reported data on smoking status provide a valid estimate of actual smoking status. In future research, we will conduct a continuous monitoring study for reliability verification of the data to reduce potential interpretation errors.

Forest Thematic Maps and Forest Statistics Using the k-Nearest Neighbor Technique for Pyeongchang-Gun, Gangwon-Do (kNN 기법을 이용한 강원도 평창군의 산림 주제도 작성과 산림통계량 추정)

  • Yim, Jong-Su;Kong, Gee Su;Kim, Sung Ho;Shin, Man Yong
    • Journal of Korean Society of Forest Science
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    • v.96 no.3
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    • pp.259-268
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    • 2007
  • This study was conducted to produce forest thematic maps and estimate forest statistics for Pyeongchang Gun using the kNN technique, which has been applied to produce thematic maps of variables of interest including unobserved plots by combining field plot data, remotely sensed data and other digital map data in forest inventories. The estimation errors for three horizontal reference areas (HRAs), whose radii are 20, 40 and 60 km respectively, were compared. Although the precision for the 40 km radius was lower compared to that for the 60 km radius, the 40 km radius was found to be an efficient HRA because their difference in precision was modest. At a value of k=5 nearest neighbors for the selected HRA, the overall accuracy was high. As a result, using the k=5 neighbors within the HRA of 40 km radius, thematic maps of number of trees, basal area, and growing stock per hectare were generated. As compared to the forest statistics based on field sample plots, the estimated means of each parameter from the produced maps were underestimated.

The Ratio-Based N Staging System Can More Accurately Reflect the Prognosis of T4 Gastric Cancer Patients with D2 Lymphadenectomy Compared with the 7th American Joint Committee on Cancer/Union for International Cancer Control Staging System

  • Hwang, Sung Hwan;Kim, Hyun Il;Song, Jun Seong;Lee, Min Hong;Kwon, Sung Joon;Kim, Min Gyu
    • Journal of Gastric Cancer
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    • v.16 no.4
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    • pp.207-214
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    • 2016
  • Purpose: The utility of N classification has been questioned after the 7th edition of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) was published. We evaluated the correlation between ratio-based N (rN) classification with the overall survival of pathological T4 gastric cancer patients who underwent D2 lymphadenectomy. Materials and Methods: We reviewed 222 cases of advanced gastric cancer patients who underwent curative gastrectomy between January 2006 and December 2015. The T4 gastric cancer patents were classified into four groups according to the lymph node ratio (the number of metastatic lymph nodes divided by the retrieved lymph nodes): rN0, 0%; rN1, ${\leq}13.3%$; rN2, ${\leq}40.0%$; and rN3, >40.0%. Results: The rN stage showed a large down stage migration compared with pathological T4N3 (AJCC/UICC). There was a significant difference in overall survival between rN2 and rN3 groups in patients with pT4N3 (P=0.013). In contrast, the difference in metastatic lymph nodes was not significant in these patients (${\geq}16$ vs. <15; P=0.177). In addition, the rN staging system showed a more distinct difference in overall survival than the pN staging system for pathological T4 gastric cancer patients. Conclusions: Our results confirm that rN staging could be a good alternative for pathological T4 gastric cancer patients who undergo D2 lymphadenectomy. However, before applying this system to gastric cancer patients who undergo D2 lymphadenectomy, a larger sample size is required to further evaluate the usefulness of the rN staging system for all stages, including less advanced stages.

A Study on Urinary Incontinence of Elderly Women in a Community (노인여성의 요실금 실태)

  • Park, Ok-Hee;Kwon, In-Soo;Kang, Young-Sil
    • Women's Health Nursing
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    • v.7 no.4
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    • pp.536-546
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    • 2001
  • The purposes of this descriptive study were to identify the prevalence rate of urinary incontinence(UI) and the differences in frequency of incontinent and normal women by general characteristics, obstetrical history, and the conditional events for urinary incontinence of the elderly women in a community. By the results of this study, it is intended to provide nursing practice guidelines for incontinent women. The research design of this study was a preliminary descriptive study. The 173 subjects were 55 years old and over, and resided in a small city area. Data were collected from June 20 to July 20, 2001, by an interview or a self-report with questionaire. The questionaire was composed of items of general characteristics, obstetrical characteristics, and conditions of UI by the modified Henderickon's Stress Incontinence Scale(1981). The results were summariezed as follows: 1. The UI prevalence rate of the sample was 64.2%. Of the incontinent women, 31.5% had experienced UI for a period of three to five years, and 84.7% had never treated or managed their UI. Frequency of UI was once or twice times per month(46.8%). 2. The total mean of UI on the scale in the incontinent women was 25.50 of 85, ranging from 18 to 41. 3. The most frequent condition of UI was coughing, followed by laughing, sneezing, heavy exercise, and preparation of urination in descending order. 4. There were significant differences in age, education, social activity, and urinary difficulty between the incontinent women and the normal women. 5. There were significant differences in frequency of spontaneous abortion, age of menopause between the incontinent women and the normal women. 6. There were no significant differences in number of delivery, frequency of artificial abortion, age of the last delivery, and postal health management between the incontinent women and the normal women. In conclusion, the incidence of UI in this study was high, but there were no effective treatments or management. It is suggested to provide the adult women with knowledge about UI, and to educate preventive behavior and control skill of urinary incontinence. Also episodes of urinary incontinence were high in the situation of sudden increase of abdominal pressure. This data can be used for the prevention strategy of urinary incontinence, In future research it is recommended to identify comprehensive factors related to urinary incontinence including psychosocial factors, and effective strategies of urinary incontinence.

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The Climacteric Symptoms and Quality of Life in Climacteric Women according to Hormone Replacement Therapy (호르몬 대체요법에 따른 갱년기여성의 갱년증상과 삶의 질)

  • Kim, Og-Mi;Lee, Young-Sook
    • Women's Health Nursing
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    • v.7 no.4
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    • pp.642-656
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    • 2001
  • The purpose of this study is to find the difference of the climacteric symptoms and quality of life according to hormone replacement therapy (HRT) in climacteric women. The research design was a descriptive survey with questionaries. A convenience sample of 181 climacteric women aged 45-65 who had climacteric symptoms were selected in Kwangju city, Korea. Sixty-six climacteric women among those subjects were receiving HRT at K university hospital in Kwangju city. Data were collected by the interview with questionaries from Feb 3. 1999 to March 25, 1999. Climacteric symptoms were measured using scores developed by Neugarten(1965) and modified by Park(1989), and the quality of life scale related to climacteric symptoms developed by Hildtich(1996) and modified Kim(1998). Data were analyzed by $x^2$-test, t-test, ANOVA and Pearson's correlation procedures, using SAS/win PC+. The results were as follows ; 1. No statistically significant differences were found between the receiving HRT group and not receiving HRT group in demographic, obstetrical and health related characteristics. 2. There were no significant difference on the climacteric symptoms between the group of women receiving HRT (score 2.4) and the group of women who were not (score 2.6) except psychological area (t= 2.407, p= 0.017). 3. The quality of life of the group of women receiving HRT was significantly higher than that the group of women who were not (t=2.151, p=.032). 4. The quality of life of the group of women receiving HRT were high scores There were significantly high of the quality of life in the vaso-motor change area (t=2.634, p= 0.009), psycho-social change area (t=3.239, p=0.001), and physical change area (t=2.031, p=0,043) in the group of receiving HRT compared to not receiving HRT group. 5. The variables showed significantly differences on the degree of climacteric symptoms of the group of women not receiving HRT were the subjective health state (t=15.81, p=0.000), age (t=7.50, p=0.007), feeling of menopause (t=30.88, p=0,000) and climacteric periods (t=8.66, p=0.003), and receiving HRT were number of para (t=3.95, p=0.050) and feeling of menopause (t=3.94, p=0.050). 6. The variables showed significantly difference on the quality of life of the group of women not receiving HRT were the subjective health state (t=4.14, p=0.044) and feeling of menopause (t=10.86, p=0.001). 7. There were significantly positive correlations between the climacteric symptoms and the quality of life in climacteric women (r=0.512, p=0.000).

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Evaluation of the Genetic Diversities and the Nutritional Values of the Tra (Pangasius hypophthalmus) and the Basa (Pangasius bocourti) Catfish Cultivated in the Mekong River Delta of Vietnam

  • Men, L.T.;Thanh, V.C.;Hirata, Y.;Yamasaki, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.671-676
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    • 2005
  • A total of 50 individual catfish, the Tra (Pangasius hypophthalmus) cultivated in either floating cages (Tra-c) or in ponds (Tra-p) and the Basa (Pangasius bocourti) raised in three floating cages, were collected in two of the Mekong Delta provinces. The caudal fin of each individual fish was used for protein electrophoresis employing the SDS-PAGE method. The one fillet sides were used as a representative sample to determine the dry matter (DM), crude protein (CP), ether extract (EE) and amino acids (AAs). The catfish oil was extracted from the belly fats, and the fatty acid (FA) composition was analyzed. There were 21 bands of the Tra and the Basa. Protein bands of the two varieties were 28.6-33.3% polymorphic, while polymorphic individuals of the Tra ranged from 80.0 to 100.0%, and the Basa was 90.0% polymorphic. The phenotypic diversity (Ho) of the Tra ranged from 1.71 to 1.80, while the Basa ranged as high as 2.14%. Diversity values (H$_{EP}$) for genetic diversity markers were equal in the Tra and the Basa. The sum of the effective number of alleles (SENA) of both varieties ranged from 3.40 to 3.83 for the Basa and the Tra, respectively. The lower values of Ho and SENA, as compared with those of the fresh water prawn (Macrobrachium equidens) in the area, would suggest that the species with the low values will become extinct due to inbreeding; the gene pools of each observed population were below a suitable threshold. Many of the differences in the nutritional values of the Tra-c, the Tra-p and the Basa were measured; their nutrient values were comparable to fishmeal or fish oil. Most of the DM, CP, and EE were higher in the Tra, especially in the Tra-c. The essential AA content, especially that of lysine, was highest in the Tra-c, next highest in the Tra-p, and lowest in the Basa. Therefore, the amino acid patterns were closer to the ideal patterns in the same sequences. In contrast, the essential FAs were concentrated in the Basa fish oil. It was found that suitable selection of parents for seed production is required to avoid inbreeding. Catfish may be valuable sources of nutrition for both humans and animals, and the differences in their nutritional values by variety and/or management must be taken into account.

Updated Meta-analysis of the Association Between CYP2E1 RsaI/PstI Polymorphisms and Lung Cancer Risk in Chinese Population

  • Wang, Ya-Dong;Yang, Hai-Yan;Liu, Jing;Wang, Hai-Yu
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.13
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    • pp.5411-5416
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    • 2014
  • Background: A number of studies have reported relationships of CYP2E1 RsaI/PstI polymorphisms with susceptibility to lung cancer in Chinese population. However, the epidemiologic results have been conflictive rather than conclusive. The purpose of this study was to address the associations of CYP2E1 RsaI/PstI polymorphisms with lung cancer risk in Chinese population comprehensively. Materials and Methods: Systematic searches were conducted in the PubMed, Science Direct, Elsevier, CNKI and Chinese Biomedical Literature Databases. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of association. Results: Overall, we observed a decreased lung cancer risk among subjects carrying CYP2E1 RsaI/PstI c1/c2 and c1/c2+c2/c2 genotypes (OR=0.76, 95%CI: 0.64-0.90 and OR=0.78, 95%CI: 0.66-0.93, respectively), as compared with subjects carrying the c1/c1 genotype. In subgroup analysis, we observed a decreased lung cancer risk among c1/c2 carriers in hospital-based studies (OR=0.81, 95%CI: 0.68-0.98) and among carriers with c1/c2 and c1/c2+c2/c2 genotypes in population-based studies(OR=0.57, 95%CI: 0.42-0.79 and OR=0.58, 95%CI: 0.43-0.79, respectively), as compared with subjects carrying the c1/c1 genotype. Limiting the analysis to studies with controls in Hardy-Weinberg equilibrium (HWE), we similarly observed a decreased lung cancer risk among c1/c2 and c1/c2+c2/c2 carriers (OR=0.73, 95%CI: 0.60-0.88 and OR=0.73, 95%CI: 0.60-0.88, respectively), as compared with c1/c1. Conclusions: Our results suggested that CYP2E1 RsaI/PstI c1/c2 and c1/c2+c2/c2 variants might be a protective factor for developing lung cancer in Chinese population. Further well-designed studies with larger sample size are required to verify our findings.