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Assessment of Water Quality and Pollutant Loads on Agricultural Watershed in Jeonbuk Province (전북지역 농업용 하천유역의 수질과 부하량 특성)

  • Uhm, Mi-Jeong;Moon, Young-Hun;Ahn, Byung-Koo;Shin, Yong-Kyu
    • Korean Journal of Environmental Agriculture
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    • v.27 no.2
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    • pp.111-119
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    • 2008
  • This study was conducted to evaluate water quality and pollutant loads on small agricultural watershed in Jeonbuk province. The EC level of investigated watershed ranged from 0.07 to 0.52 dS/m, BOD level ranged from 0.1 to 5.0 mg/L, and $COD_{Cr}$ level ranged from 0.6 to 17.7 mg/L. As above, contents of water quality indicators covered wide range, but each indicator was alike in mean content every other year. The contents of EC, $Ca^{2+},\;Mg^{2+},\;K^+\;and\;Na^+$ were decreased in rainy season, but the contents of BOD, $COD_{Cr},\;COD_{Mn}$, T-N and T-P were not greatly different as compared to dry season. And high content of SS showed substantial sediments near the surface flow out and influence on water system in rainy season. The pollutant loads measured in terminal of watershed were $9.6{\sim}757.9$ kg/day for BOD, $51.2{\sim}1418.5$ kg/day for T-N and $0.3{\sim}44.7$ kg/day for T-P. The pollutant loads of BOD, T-N and T-P in rainy season increased several times as compared to dry season. In rainy season, watershed with more than 30% in the proportion of paddy field to land showed relatively low discharge and pollutant loads in comparison to watershed with less than 30%. The discharge of watershed in rainy season increased 5.7times compared with the dry season in watershed with less than 30% in the proportion of paddy field to land, whereas was only 2.3times in watershed with more than 30%. The correlation coefficient($R^2$) of regression between discharge and pollutant loads of T-N were higher than those of BOD and T-P.

The Relationship Between Adiposity and Risk factors for Cadiovascular Disease at Normal Body Weight Male (정상 체중인 성인 남성에서 지방과다와 심혈관질환의 위험요인간의 관련성)

  • Kwon, Woo-Sung;Kim, Jun-Su;Chae, Jin-Wook;Lee, Keun-Mi;Jung, Seung-Pil;Moon, Yong
    • Journal of Yeungnam Medical Science
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    • v.20 no.1
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    • pp.62-70
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    • 2003
  • Background: Most of all studies about the relation between the health risk and obesity are based on the European and American data. The purpose of this study is to examine the relation between adiposity and risk factors for cardiovacular disease (CVD) in normal weight individuals. Materials and Methods: Normal weight subjects with a body mass index (BMI) between 18.5 and $23kg/m^2$ (76 subjects) and overweight subjects with a BMI between 23 and $25kg/m^2$ (53 subjects) were retained for this study. Normal weight subjects were divided into three group of each adiposity variable, then three group and the overweight group were evaluated for the presence of CVD risk factors and analyze the correlation coefficients between adiposity variables and risk factors controlled for age in normal weight, overweight groups. Using logistic regression analysis, the odds ratio (OR) for the prevalence of risk factors for each group of adiposity variables and the overweight group was estimated relative to the first group in normal weight subjects. Results: Systolic BP, diastolic BP, LDL cholestrol, HDL cholesterol, triglycerides in normal weight subjects were significantly correlated with all adiposity variables (P<0.01). Third group (3.7 for %fat and 4.7 for fat mass)of adiposity variables in the normal weight group and the overweight group (6.6 for %fat and 11.5 for fat mass) tended to have higher ORs compared to first group for risk factor variables. Conclusion: Normal weight subjects with elevated adiposity had higher prevalence of risk factors than normal weights subjects with less adiposity. Measuring of adiposity added additional information of cardiovascular disease risk factors in normal weight subjects.

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Pelvic Measurement Indicators to Produce the Gonad Protection of Female Infants (유아기 여아의 생식선 차폐체 제작을 위한 골반 지표 계측)

  • Kwak, Jong-hyeok;Park, Chan-hyeok;Moon, deog-hwan
    • Journal of the Korean Society of Radiology
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    • v.10 no.2
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    • pp.101-107
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    • 2016
  • It was performed in this study to provide basic information on production of accurate gonadal shield by measuring pelvic indicators of TDP SD ISP IAD 1CDP and 2CDP. when pelvis ap and hip ap examination was taken, there is no exact position of the reference point of the shield and anatomically more difficult to shield gonad in the case of female infants than male. Results analyzed by height in 70~80 and 110~120 were approximately 30mm 13mm 19mm 20mm 2mm and 7mm difference in TDP SD ISP IAD 1CDP and 2CDP respectively. This value was statistically significant (P<0.05). Results analyzed by age of 2~3 and 6~7 were different on SD ISP IAD and 2CDP by 17mm 10mm 12mm 16mm respectively. it was also statistically significant. However 1CDP was not statistically significant(P>0.05). the difference was nearly about 1mm. Analysis of results by weight of less than 10 and more than 20 showed difference on TDP SD ISP IAD 1CDP and 2CDP by 28mm 14mm 11mm 20mm 3mm and 8mm. it was statistically significant (P<0.05). From the above results, female infants pelvic indicator measurement can be used as reference value for shielding production and especially IAD can present a reference point on the shielding position. Pelvis indicators of female infant has a close correlation. In addition, as it is showen in the statistical difference analysis to have an accurate ovarian shield, gonad shield would be produced and used by height, age and weight.

In Vitro imaging of MRI and Ultrasound for Colorectal Carcinoma (직결장암 조직의 자기공명영상과 초음파 소견에 대한 비교 연구)

  • Lee, Hwang Kyu;Jee, Keum Nahn;Hong, Sujin;Koh, Jae Hyang
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.2
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    • pp.133-143
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    • 2013
  • Purpose : To evaluate and compare the accuracy of magnetic resonance imaging (MRI) and ultrasound (US) for detection and estimation of invasion depth of colorectal carcinoma (CRC) by correlation with histopathologic findings in vitro, and to find out the best MR pulse sequence for accurate delineation of tumor from surrounding normal tissue. Materials and Methods: Resected specimens of CRC from 45 patients were examined about tumor detectability and invasion depth of US using high frequency (5-17 MHz) linear transducer in a tube filled with normal saline and MRI in a 8-channel quadrate head coil. The institutional review board approved this study and informed consent was waived. MRI with seven pulse sequences of in- and out-of-phases gradient echo T1 weighted images, fast spin echo T2 weighted image and its fat suppression image, fast imaging employing steady-state acquisition (FIESTA) and its fat suppression image, and diffusion weighted image (DWI) were performed. In each case, both imaging findings of MRI and US were evaluated independently for detection and estimation of invasion depth of tumor by consensus of two radiologists and were compared about diagnostic accuracy according to the histopathologic findings as reference standard. Seven MR pulse sequences were evaluated on the point of accurate delineation of tumor from surrounding normal tissue in each specimen. Results: In specimens of CRC, both imaging modalities of MRI (91.1%) and US (86.7%) showed relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of tumor. In early CRC, diagnostic accuracy of US was 87.5% and that of MRI was 75.0%. There was no statistically significant difference between two imaging modalities (p > 0.05). The best pulse sequence among seven MR sequences for accurate delineation of tumor from surrounding normal tissue in each specimen of CRC was fast spin echo T2 weighted image. Conclusion: MRI and US show relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of resected specimen of CRC. The most excellent pulse sequence of MRI for accurate delineation of tumor from surrounding normal tissue in CRC is fast spin echo T2 weighted image.

Effects of Horseshoe Expander (Horseshoe Expander의 확장 효과에 관한 연구)

  • Chung, Kyu-Rhim;Park, Young-Guk;Lee, Young-Jun;Kim, Hong-Suk
    • The korean journal of orthodontics
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    • v.30 no.5 s.82
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    • pp.553-563
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    • 2000
  • Horseshoe Expander is one of Slow Maxillary Expansion(SME) which aims to accommodate the contra- lateral expansion and midpalatal suture expansion or the palate. The appliance consists of skeleton type strew embedded in split Horseshoe appliance. It is the objectives of the presentation to manifest the changes in dental & craniofacial components subsequent to the application of Horseshoe Expander. The subjects for this study consisted of 32 patients (mean age : 12.7). frontal, lateral cephalometric headfilm were taken and study casts were fabricated before and after expansion. 24 items were measured, compared preexpansion with postexpansion. Especially, palatal volume was measured by means of 'Hydro-measurement method'. Tooth axis measurement on the dental casts were made with Universal bevel protractor, and Horseshoe Expander group were compared with RME group. This study of changes to maxillary expansion with Horseshoe Expander revealed the following significant results. 1. Triangular-shaped expansion pattern appeared in frontal cephalometric headfilm. 2. Palatal plane, occlusal plane, mandibular plane and upper incisor to FH increased in lateral cephalometrir headfilm. 3. Palatal volume increased significantly. A slight bite opening, reduction of occlusal contact points showed in dental casts. 4. A 2.2:1 ratio of the amount of intermolar width in maxilla(orthodontic movement) to maxillary width (orthopedic movement) was determined. 5. Horseshoe Expander group has less buccal tipping tendency than RME group, by taking high correlation coefficients in the upper second premolar and first molar. It was suggested that Horseshoe Expander showed less orthodontic changes, less buccal tipping tendency. In addition, it was effective in maxillary expansion.

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An evaluation of the adequacy of pont's index (Pont 지수의 임상적 적합성에 대한 평가)

  • Kim, Seong-Hun;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.30 no.1 s.78
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    • pp.115-126
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    • 2000
  • Dental arch expansion is one of the method used to solve the dental crowding problem by non-extraction. Many formulae using tooth size have been suggested to predict ideal inter-premolar and inter-molar width. The purpose of this study was to evaluate the adequacy of some upper dental arch width prediction methods, namely Pont's method, Schmuth's method and Cha's method. The sample consisted of the casts of 119 Korean young adults who had no muscular abnormality, no skeletal discrepancy, and Angle's Class I molar relationships. Measurements were obtained directly from plaster casts; they Included mesiodistal crown diameters of the four maxillary incisors, as well as maxillary inter-first-premolar and inter-first-molar arch widths as specified by Pont. The correlation coefficients between the sum of incisors(SI) and upper dental arch width were calculated. The differences between predicted width and actual width were classified as overestimated, properestimated, and underestimated. The data obtained from each group were analyzed for statistical differences. The results were as follows : 1. Upper dental arch width indices were calculated from SI in normal occlusion (81.96 : premolar index, 62.55 : molar index). 2. Low correlations between SI and arch width were noted in normal occlusion (0.50 in the inter-premolar width, 0.39 in the inter-molar width). 3. Pont's formula and Schmuth's formula tended to overestimate the inter-premolar width. A more even distribution of estimates was noted in Cha's fomula. 4. Cases within $\pm$1 mm range of observed inter-premolar width were $45\%$ in the Cha's formula, $40\%$ in the Pont's formula, and $39\%$ in the Schmuth's formula. 5. All formulae had a tendency to underestimate the inter-molar width, but Cha's formula had better predictability than others. 6. Cases within $\pm$1 mm range of observed inter-molar width were $40\%$ in the Cha's formula, $29\%$ in the Pont's formula, and $13\%$ of Schmuth's formula. The data presented in this study does not support the clinical usefulness of ideal arch width prediction methods using the mesiodistal width of maxillary incisors.

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EFFECTS OF ACID ETCHING TIMES ON ENAMEL SURFACE MORPHOLOGY AND SHEAR BOND STRENGTH OF ORTHODONTIC ATTACHMENT TO ENAMEL (산부식시간이 법랑질 표면 부식형태와 교정장치의 전단접착강도에 미치는 영향에 관한 연구)

  • Nahm, Dong-Seok;Suhr, Cheong-Hoon;Yang, Won-Sik;Chang, Young-Il
    • The korean journal of orthodontics
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    • v.27 no.5 s.64
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    • pp.771-779
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    • 1997
  • The purpose of this in vitro study was to evaluate the effects of different acid etching times on the enamel surface morphology, shear bond strength and debonding failure mode of orthodontic attachment. Ninety six extracted human mandibular premolars were divided into eight groups of twelve teeth. The buccal surfaces were etched with $37\%$, phosphoric acid for 5, 10, 15, 30, 45, 60, 90 and 120 seconds, respectively. Two teeth from each group were used for scanning electron microscope examination. On the etched buccal surfaces of remaining teeth, orthodontic attachments(lingual buttons) were bonded with light cured orthodontic adhesive. Twenty foot hours after bonding, a Instron universal testing machine was used to determine shear bond strength of orthodontic attachment to enamel. After debonding, bases of orthodontic attachments and enamel surfaces were examined under stereoscopic microscope to determine failure mode. Statistical analysis of the data was carried out with one nay ANOVA and Duncan's multiple range test The results were as follows; 1. There was no statistically significant difference in shear bond strengths between the various etching times(p<0.05). 2. The failure modes of orthodontic attachments had some differences. In 5, 10 and 15 seconds etching groups, the percentage of adhesive/enamel interface failure was higher than that of adhesive/attachment interface failure. On the contrary, in 30, 45, 60, 90 and 120 seconds etching groups, the results were reversed. 3. The etching patterns of enamel surfaces had a great variation. So, we could not find any correlation between etching pattern and bond strength. 4. The findings in this study indicate that in vitro reduction of the etching me to 5 seconds maintains clinically acceptable bond strength. However, further study is required to determine the cause of failure mode in 5, 10 and 15 seconds groups.

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Factors Related to Health Promoting Behaviors of Young-Old and Old-Old Elderly in Rural Areas (농촌지역 전기노인과 후기노인의 건강증진행위 관련요인)

  • Lee, Myung-Suk;Lim, Hyun-Ja
    • Journal of agricultural medicine and community health
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    • v.35 no.4
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    • pp.370-382
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    • 2010
  • Objectives: The purpose of this study was to investigate the level of health promoting behaviors and the significant factors in rural elderly(young-old vs old-old). Methods: The data was collected using structured questionnaires from June 22th to Sep. 18th, 2009. A total of 556 elderly aged 65 years or over were selected from 14 rural districts in C province, South Korea. Age was divided into two groups as below 65-74 and 75 or older. A structured questionnaire was used to obtain information on the demographic characteristics, their perceived health status, the difficulty of activities of daily living, quality of life, self-efficacy and health promoting behaviors. The health promoting behaviors included nutrition, stress management, interpersonal support, exercise, health responsibility and self-actualization. The scores for health promoting behaviors were used mean and standard deviation. The data was analyzed using SPSS Win 12.0. Results: Of the 556 subjects, we found that the young-old(65-74 aged) were 359 and the old-old elderly(over 75 aged) were 197. We found that the level of health promoting behavior was higher for young-old ($2.75{\pm}0.374$) compared to old-old elderly people ($2.67{\pm}0.399$). In multiple linear regression, quality of life, self-efficacy, living with spouse, and number of generation living together for the young-old, and quality of life for old-old elderly were significantly associated with health promoting behaviors. Conclusions: The study findings indicate that there are age differences in associated factor of health promoting behaviors. Therefore our findings may provide useful assistance in developing effective intervention programs to improve health promoting behavior of the elderly in rural areas according to their age differences.

Ionic composition and pollution characteristics of precipitation in Jeju Island during 2009-2014 (2009-2014년 제주지역 강수의 이온조성 및 오염특성)

  • Bu, Jun Oh;Song, Jung Min;Shin, Su Hyun;Kim, Won Hyung;Kang, Chang Hee
    • Analytical Science and Technology
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    • v.29 no.1
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    • pp.19-28
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    • 2016
  • The objective of this study was to determine the acidification of precipitation in the Jeju area. Precipitation samples were collected from the Jeju area from 2009-2014, and the major ionic species were analyzed. In the regression analysis, through a comparison of ion balance, electric conductivity, and acid fraction, the correlation coefficients showed a good linear relationship within the range of 0.927~0.983. The volume-weighted means of the pH and electric conductivity were 4.9 and 22.7 µS/cm, respectively. The ionic strength of precipitation was 0.27±0.38 mM, indicating about 35.9 % of total precipitation within the pure precipitation criteria. The volume-weighted mean concentrations (ìeq/L) of the ionic species in the precipitation were in the order of Na+ > Cl > nss-SO42− > NO3 > NH4+ > Mg2+ > H+ > nss-Ca2+ > PO43− > K+ > HCOO > CH3COO > NO2 > F > HCO3 > CH3SO3 . The acidification contributions by sulfuric and nitric acids were 54.5 % and 36.5 %, respectively. Meanwhile the acidification contributions by formic and acetic acids were 4.8 % and 4.2 %, respectively. Thus, it was found that the acidification of the precipitation in the Jeju area was mainly due to the inorganic acids. The neutralization factors by NH3 and CaCO3 were also 33 % and 20 %, respectively.

Cadmium Concentrations in Environmental Tobacco Smoke of Indoor Environments (실내환경의 환경성담배연기(ETS) 중 카드뮴에 관한 연구)

  • Ha, Kwon Chul;Park, Dong-Uk;Yoon, Chung Sik
    • Analytical Science and Technology
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    • v.16 no.4
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    • pp.299-308
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    • 2003
  • The purpose of this study is to investigate cadmium concentrations among metals in ETS (Environmental Tobacco Smoke) of indoor environments and to evaluate the cadmium as a marker of ETS. The correlations of cadmium concentrations and nicotine, 3-EP, RSP, SD (Smoking Density), and SI (Smoking Index). Air samples of metals, nicotine, 3-EP, and RSP were taken in smoking room, smoking allowed office, corridor outside smoking room, and non-smoking office respectively. The SD, ACH, and SI were investigated during sampling. Airborne concentration of cadmium known as human carcinogen were qualified and quantified. The SD was 0.2 to $2.6cig/m^2{\cdot}hr$, and the mean value of SD in smoking rooms was $1.2cig/m^2{\cdot}hr$ that is higher than other researches. The mean of ACH in smoking rooms was 11.1. The concentrations of cadmium showed log-normal distributions and the geometric mean concentrations of cadmium in smoking rooms, corridor outside smoking rooms, smoking allowed offices, and non-smoking offices were $0.045{\mu}g/m^3$, $0.018{\mu}g/m^3$, $0.021{\mu}g/m^3$, and $0.017{\mu}g/m^3$ respectively. The concentrations of cadmium in smoking room showed significant difference according to category of indoor office environments (p<0.05) and showed compliance with occupational exposure limits. The correlation coefficients between cadmium and nicotine, 3-EP, and RSP were 0.53, 0.41, 0.43 respectively. The cadmium among metals showed the highest correlations (r=0.63) with SI. It was recommended cadmium among metals is a good indicator for ETS.