• Title/Summary/Keyword: R/S method

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A comparative study of electroplating and electroless plating for diameter increase of orthodontic wire (교정용 선재의 직경 증가를 위한 전기도금법과 무전해도금법의 비교연구)

  • Kim, Jae-Nam;Cho, Jin-Hyoung;Sung, Young-Eun;Lee, Ki-Heon;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
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    • v.36 no.2 s.115
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    • pp.145-152
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    • 2006
  • The purpose of this study was to evaluate electroless plating as a method of increasing the diameter of an orthodontic wire in comparison with eletroplating. After pretreatment plating of the 0.016 inch stainless steel orthodontic wire, electroless plating was performed at $90^{\circ}C$ until the diameter of the wire was increased to 0.018 inch. During the process of electroless plating, the diameter of the wire was measured every 5 minutes to examine the increasing ratio of the wire's diameter per time unit. And to examine the uniformity, the diameter at 3 points on the electroless-plated orthodontic wire was measured. An X-ray diffraction test for analyzing the nature of the plated metal and a 3-point bending test for analyzing the physical property were performed. The electroless-plated wire group showed a increased tendency for stiffness, yield strength, and ultimate strength than the electroplated wire group. And there was a statistically significant difference between the two groups for stiffness and ultimate strength. In the electroless-plated wire group, the increasing ratio of the diameter was $0.00461{\pm}0.00003mm/5min$ (0.00092 mm/min). In the electroplated wire group, it was $0.00821{\pm}0.00015mm/min$. The results of the uniformity test showed a tendency for uniformity in both the plating methods. The results of this study suggest that electroless plating of the wire is closer to the ready-made wire than electroplating wire in terms of the physical property. However, the length of plating time needs further consideration for the clinical application of electroless plating.

Evaluation on Protrusion of the Imaginary Prostate Volume Using Three-Dimensional Volume Rendering (3차원 볼륨 렌더링을 이용한 가상 돌출형 전립선 부피 평가)

  • Seoung, Youl-Hun;Joo, Yong-Hyun;Rhim, Jae-Dong;Choe, Bo-Young
    • Progress in Medical Physics
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    • v.20 no.4
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    • pp.208-215
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    • 2009
  • This study is to compare the accuracy of evaluation regarding the volume of the prostate, which three-dimensional volume rendering was produced the shape of protrusion, by measuring two kinds of craniocaudal length from the top of the protrusion and from the exclusion of the protrusion as the starting points. For the imaginary protrusion prostate models, total of 10 models were roughly made by using devils-tongue jelly and changing each of the 10 ml of capacity from 10 ml to 100 ml. For the protrusion prostate models aimed at estimating the real volume, through 64 cannel computed tomography (CT) and 3.0 tesla magnetic resonance image (MRI) were conducted by planimetry technique from three-dimensional volume rendering. And then we performed to evaluate on significance of these volumes by wilcoxon signed rank test. Also the obtained volumes data by ellipsoid volume formula were measured the volume of protrusion prostate models two times with each method using the two kinds of craniocaudal length from top of the protrusion and from exclusion of the protrusion as the starting points. Finally, the significance of differences using wilcoxon signed rank test was evaluated between the real volume by planimetry technique and the measured volume by ellipsoid volume formula from three-dimensional volume rendering. The average of the protrusion length on the models was $0.90{\pm}0.18\;mm$ in CT and was $0.75{\pm}0.11\;mm$ in MRI. There were not statistically significant difference between MRI and CT from the volume of protrusion prostate models (p=0.414). In MRI (p=0.139) and CT (p=0.057), there were not statistically significant difference between the real volume by planimetry technique and the measured volume by ellipsoid volume from exclusion of the protrusion as the starting points. While, there were statistically significant difference between the real volume by planimetry technique and the measured volume by ellipsoid volume from top of the protrusion as the starting points in MRI (p=0.005) and CT (p=0.005). For the accurate measurement of the protrusion prostate models, the craniocaudal length of the prostate should be measured from the exclusion of the protrusion as the starting points.

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Determining Nitrogen Topdressing Rate at Panicle Initiation Stage of Rice based on Vegetation Index and SPAD Reading (유수분화기 식생지수와 SPAD값에 의한 벼 질소 수비 시용량 결정)

  • Kim Min-Ho;Fu Jin-Dong;Lee Byun-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.5
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    • pp.386-395
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    • 2006
  • The core questions for determining nitrogen topdress rate (Npi) at panicle initiation stage (PIS) are 'how much nitrogen accumulation during the reproductive stage (PNup) is required for the target rice yield or protein content depending on the growth and nitrogen nutrition status at PIS?' and 'how can we diagnose the growth and nitrogen nutrition status easily at real time basis?'. To address these questions, two years experiments from 2001 to 2002 were done under various rates of basal, tillering, and panicle nitrogen fertilizer by employing a rice cultivar, Hwaseongbyeo. The response of grain yield and milled-rice protein content was quantified in relation to RVIgreen (green ratio vegetation index) and SPAD reading measured around PIS as indirect estimators for growth and nitrogen nutrition status, the regression models were formulated to predict PNup based on the growth and nitrogen nutrition status and Npi at PIS. Grain yield showed quadratic response to PNup, RVIgreen around PIS, and SPAD reading around PIS. The regression models to predict grain yield had a high determination coefficient of above 0.95. PNup for the maximum grain yield was estimated to be 9 to 13.5 kgN/10a within the range of RVIgreen around PIS of this experiment. decreasing with increasing RVIgreen and also to be 10 to 11 kgN/10a regardless of SPAD readings around PIS. At these PNup's the protein content of milled rice was estimated to rise above 9% that might degrade eating quality seriously Milled-rice protein content showed curve-linear increase with the increase of PNup, RVIgreen around PIS, and SPAD reading around PIS. The regression models to predict protein content had a high determination coefficient of above 0.91. PNup to control the milled-rice protein content below 7% was estimated as 6 to 8 kgN/10a within the range of RVIgreen and SPAD reading of this experiment, showing much lower values than those for the maximum grain yield. The recovery of the Npi applied at PIS ranged from 53 to 83%, increasing with the increased growth amount while decreasing with the increasing Npi. The natural nitrogen supply from PIS to harvest ranged from 2.5 to 4 kg/10a, showing quadratic relationship with the shoot dry weight or shoot nitrogen content at PIS. The regression models to estimate PNup was formulated using Npi and anyone of RVIgreen, shoot dry weight, and shoot nitrogen content at PIS as predictor variables. These models showed good fitness with determination coefficients of 0.86 to 0.95 The prescription method based on the above models predicting grain yield, protein content and PNup and its constraints were discussed.

Antimicrobial Effects against Food-Borne Pathogens and Antioxidant Activity of Rhododendron brachycarpum Extract (만병초 추출물의 식중독 유발균에 대한 항균효과 및 항산화활성)

  • Choi, Moo-Young;Rhim, Tae-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.10
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    • pp.1353-1360
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    • 2011
  • This study was performed to investigate the antimicrobial effects against food-borne pathogens and antioxidant activity of Rhododendron brachycarpum ethanol-extract. The antimicrobial activity of the extract was determined using a paper disc-diffusion method, and the diameter of the clear zone was measured. The diameter of the clear zone in the presence of 10 mg of extract was maximal against Bacillus cereus among the three tested Gram-positive bacteria and against Escherichia coli O157:H7 among the five tested Gram-negative bacteria. Analysis of the minimum inhibitory concentration (MIC) showed that the extract exhibited a similar efficacy as that of sorbic acid, a well-known chemical preservative. The growth inhibitory effects of the extract at concentrations of 250, 500, 1,000, and 2,000 mg/L on food-borne pathogens were determined against Staphylococcus aureus, Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7. Growth of the microorganisms was not affected by the extract at concentrations up to 250 mg/L, but it was significantly (p<0.05) inhibited by the extract at concentrations higher than 1,000 mg/L. The antioxidant effects of the extract were examined via measurement of DPPH radical scavenging activity, inhibition of reactive oxygen species (ROS) generation using fluorescent dichlorofluorescien (DCF) assay, and prevention of peroxyl radical- and hydroxyl radical-induced supercoiled DNA breakage. The $IC_{50}$ of the extract for DPPH radical scavenging activity was about half that of ${\alpha}$-tocopherol, which was used as a positive control. DCF fluorescence intensity decreased as the concentration of the extract increased, demonstrating that ROS generation was inhibited in a concentration-dependent manner. The ROS inhibitory effect of the extract was higher than that of ascorbic acid. The extract prevented supercoiled DNA strand breakage induced by peroxyl radical and hydroxyl radical. Thus, the results of the present study demonstrate that the extract exhibits antimicrobial effects against food-borne pathogens as well as potent antioxidant capacity, suggesting that R. brachycarpum could be used as a natural antibacterial agent and effective antioxidant in food.

Combustion Characteristic Study of LNG Flame in an Oxygen Enriched Environment (산소부화 조건에 따른 LNG 연소특성 연구)

  • Kim, Hey-Suk;Shin, Mi-Soo;Jang, Dong-Soon;Lee, Dae-Geun
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.1
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    • pp.23-30
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    • 2007
  • The ultimate objective of this study is to develop oxygen-enriched combustion techniques applicable to the system of practical industrial boiler. To this end the combustion characteristics of lab-scale LNG combustor were investigated as a first step using the method of numerical simulation by analyzing the flame characteristics and pollutant emission behaviour as a function of oxygen enrichment level. Several useful conclusions could be drawn based on this study. First of all, the increase of oxygen enrichment level instead of air caused long and thin flame called laminar flame feature. This was in good agreement with experimental results appeared in open literature and explained by the effect of the decrease of turbulent mixing due to the decrease of absolute amount of oxidizer flow rate by the absence of the nitrogen species. Further, as expected, oxygen enrichment increased the flame temperatures to a significant level together with concentrations of $CO_2$ and $H_2O$ species because of the elimination of the heat sink and dilution effects by the presence of $N_2$ inert gas. However, the increased flame temperature with $O_2$ enriched air showed the high possibility of the generation of thermal $NO_x$ if nitrogen species were present. In order to remedy the problem caused by the oxygen-enriched combustion, the appropriate amount of recirculation $CO_2$ gas was desirable to enhance the turbulent mixing and thereby flame stability and further optimum determination of operational conditions were necessary. For example, the adjustment of burner with swirl angle of $30\sim45^{\circ}$ increased the combustion efficiency of LNG fuel and simultaneously dropped the $NO_x$ formation.

Estimation and Methods Estimating Daily Food Consumption of Agrammus agrammus (노래미, Agrammus agrammus의 일간섭식량 추정법과 추정)

  • KIM Chong-Kwan;KANG Yong-Joo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.4
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    • pp.241-250
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    • 1992
  • This study was covered the amount of food consumed per day as well as methods estimating the daily food consumption per fish of Agrammus agrammus in natural population to understand flow of food organisms among trophic levels in bio-community of the coastal waters, Shinsudo, Samchonpo. The estimating formulas were induced from the mathematical models that representing the diurnal fluctuation of the stomach fullness of the fish. The daily food consumption could be estimated by both feeding rates and gastric evacuation rates, but it was more reasonable method that based on gastric evacuation rates than feeding rates. The daily food consumption in wet weight per fish by gastric evacuation rates were 1.9856g/day, 3.4725g/day, 4.4418g/day, 5.8168g/day, and 7.2113g/day in the order of age groups from 0 to 4. The daily rations as percentage of body weight were $9.35\%,\;6.65\%,\;5.76\%,\;4.72\%\;and\;5.31\%$ in the order of ages. The daily food consumption was proportional to the body weight of fish, but the daily food consumption per specific body weight was reciprocal to the body weight. Annual food consumption in wet weight. per fish by gastric evacuation rates were 529.98g from the age of 0.25 to 1.0, 1,269.28g from the age of 1.0 to 2.0, 1,622.76g from the age of 2.0 to 3.0, 2,125.57g from the age of 3.0 to 4.0, 1,316.09g from the age of 4.0 to 4.5 The amount of food consumed per fish during 4.25 years, from the age of 0.25 to 4.5, was 6,863.68g in wet weight. the relationships between the daily food consumption(Dr) by gastric evacuation rates and the total length(L, cm) or the body weight(W, g) were as follows: $$Dr=0.036L^{1.702}$$ $$Dr=0.254W^{0.664}$$

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Occurrence and distribution of ALS inhibiting herbicide-resistant weeds in the paddy field of Gyeongnam province (경남지역 ALS 저해 제초제 저항성 논잡초의 발생 및 분포)

  • Lee, Yong Hyun;Shim, Soo Yong;Kim, Jin-Won;Lee, Jeongran;Park, Kee Woong;Lee, Jeung Joo
    • Weed & Turfgrass Science
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    • v.7 no.3
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    • pp.209-218
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    • 2018
  • This study was carried out to investigate the occurrence and distribution of ALS inhibiting herbicide-resistant weeds and to estimate the appeared areas of resistant weeds in the paddy fields of Gyeongnam province of Korea in 2017 and 2018 using a soil assay method. Compared with the 2012 survey, this study showed that the infested ratio of ALS inhibiting herbicide-resistant weeds increased from 1.0% to 66.8% and the infested area increased from 876 ha to 49,008 ha. The infested area of ALS inhibiting herbicide-resistant weeds was estimated in Ulsan-si (8.4%), Hapcheon-gun (8.3%), Haman-gun (7.9%), Goseong-gun (7.9%), Hadong-gun (7.3%), Jinju-si (7.2%), Changnyeong-gun (7.0%), Gimhae-si (6.4%), Miryang-si (5.5%), Busan-si (4.9%), Uiryeong-gun (4.6%), Namhae-gun (4.3%), Geochang-gun (4.2%), Changwon-si (3.8%), Geoje-si (2.9%), Yangsan-si (1.8%), Sancheong-gun (0.9%) and Tongyeong-si (0.4%), and the herbicide resistant weeds was not occurred in Hamyang-gun. The most dominant ALS inhibiting herbicide-resistant weeds in paddy fields were Monochoria vaginalis, followed by Echinochloa oryzicola, Lindernia dubia, Scirpus juncoides, Ludwigia prostrata, Cyperus difformis, Sagittaria trifolia and Rotala indica. ALS inhibiting herbicide-resistant M. vaginalis, L. dubia, and E. oryzoides occurred throughout Gyeongnam province, and ALS inhibiting herbicide-resistant S. trifolia and R. indica were only found in Gimhae-si. Therefore, these results will be utilized to estimate population dynamics of ALS inhibiting herbicide-resistant weeds and provide proper management practices in the paddy fields of Gyeongnam province.

Clinical and Immunologic Features of Miliary Tuberculosis with Positive Bone Marrow Study (골수생검 양성인 속립성 결핵의 고찰)

  • Song, Kwang-Seon;Yong, Suk-Joong;Shin, Kye-Chul;Lee, Won-Yeon;Ryu, Jeong-Seon
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.1
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    • pp.22-29
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    • 1996
  • Background: Abnormalities of the peripheral blood are frequent and varied in patients with miliary tuberculosis. Anemia, leukopenia, thrombocytopenia, pancytopenia, monocytosis, basophilia, eosinophilia and leukemoid reactions have been reported. These abnormalities are more frequent in patients with positive bone marrow study. In this report, we evaluated clinical, hematological and immunological features in patients with miliary tuberculosis in order to know whether difference is existed between "bone marrow biopsy positive group(pathologically proven to miliary tuberculosis)" and "negative group". Method: Clinical evaluation, serum ADA, sIL-2R, and T-lymphocyte subsets were measured in 40 patients with miliary tuberculosis who received bone marrow biopsy. Results: 1) The average age of patients was 39 year-old. There were 23 male and 17 female patients. Associated extrapulmonary tuberculosis are 9 CNS tuberculosis, 6 joint tuberculosis, and 2 tuberculous pleurisy. 2) Sixteen of the 40 patients were positive bone marrow biopsy(60%). 3) Sixteen of the 40 patients(60%) had anemia(11 positive patients: 13 negative patients). Leukopenia occurred in 12 per cent(4:1). Thrombocytopenia was noted in 10%(3:1). 4) The mean value of serum ADA was 83 U/L(90 U/L: 70.6 U/L, p=0.23). 5) The mean activity of Soluble IL-2 receptor was 4,643 pmol/L($6840{\pm}7446\;pmol/L$: $1,897{\pm}1,663\;pmol/L$, p=0.06). 6) In the T lymphocyte subsets, the percent of T-lymphocytes was 64%(62%:73%, p=0.2). In some patients(9), $T_4$ and $T_8$ ratio in BAL fluid($1.97{\pm}1.2$) was higher than that in the peripheral blood($1.16{\pm}0.5$). Conclusion: Bone marrow examination are diagnostic in 60% of cases of miliary tuberculosis. Percents of the total T lymphocyte and helper T cell in BAL are more elevated than in peripheral blood. There was no significant difference in peripheral blood abnormalities and marker of T lymphocyte activation between the bone marrow biopsy positive and negative group.

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Comparison of a whole blood Interferon-γ assay and A tuberculin skin test for detecting latent tuberculosis infection in children (소아 잠복 결핵 감염 진단에 있어서 투베르쿨린 피부반응 검사와 결핵 특이항원 자극 Interferon-γ 분비능 측정의 비교)

  • Chun, Jin-Kyong;Kim, Chang Ki;Kim, Hyun Sook;Jung, Ghee Young;Linton, John A.;Kim, Ki Hwan;Lee, Taek Jin;Jeon, Ji Hyun;Kim, Dong Soo
    • Clinical and Experimental Pediatrics
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    • v.51 no.9
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    • pp.971-976
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    • 2008
  • Purpose : Surveillance for detecting and managing latent tuberculosis infection (LTBI) is a key component of tuberculosis control. The classic surveillance tool, the tuberculin skin test (TST), may have some limitations when used in the Bacillus Calmette-$Gu{\acute{e}}rin$ (BCG)-vaccinated population. The object was to perform a blood test $QuantiFERON^{(R)}$-TB Gold In Tube (QFT-G IT) based on the detection of interferon-$\gamma$ ($IFN-{\gamma}$) released by T cells in response to Mycobacterium tuberculosis-specific antigens, and to compare the efficacy of this new diagnostic tool for LTBI with that of TST. Methods : For six months, between October 1, 2006 and April 30, 2007, data were collected from 111 patients under 15 years of age at Severance Children's Hospital. TST and QFT-G IT tests were performed with children with or without contact histories of tuberculosis. In addition to these tests, we examined comparative data from 29 adults who had tuberculosis, to detect false negative rates in the QFT-G IT method. Results : Thirty-three children had household contact histories. In this group, 15% and 42% of cases were found to be positive using the QFT-G IT assay and TST, respectively. Agreement was low between these two tests (${\kappa}=0.39$). In the adult active tuberculosis group, the QFT-G IT false negative rate defined as a positive culture and a negative QFT-G IT result was 12.5%. Conclusion : In diagnosing LTBI in children, the usefulness of a whole-blood $IFN-{\gamma}$ assay employing TB-specific antigens will be revealed only by examining additional longitudinal clinical data; this study serves as a starting point in that process.

Factors for the Prediction of Pain in Terminally Ill Cancer Patients in Hospice Units (호스피스 병동에 입원한 말기 암환자의 통증 예측요인)

  • Yong, Jin-Sun;Han, Sung-Suk;Ro, You-Ja;Hong, Hyun-Ja
    • Journal of Hospice and Palliative Care
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    • v.5 no.2
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    • pp.125-135
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    • 2002
  • Purpose : The purpose of this study was to investigate the impact of depression, discomfort, spirituality, physical care, and opioid use on pain with terminally ill cancer patients in the hospice units. Method : The convenient sample of this study consisted of 58 terminally ill cancer patients at three hospice units in university-affiliated hospitals. Patients were interviewed with structured questionnaires. The data was analyzed using ANOVA, Pearson correlation coefficient, and multivariate multiple regression. Result : The results of this study were as follows : 1) The mean age of the participants was approximately 57 years. Regarding diagnosis, stomach cancer showed the highest frequency (24.1%), followed by lung cancer (17.2%) and rectal cancer (13.8%). Regarding motivation for admission to the hospice unit, the majority of the participants indicated pain control (67.2%), followed by spiritual care (39.7%), and symptom relief (27.6%). 2) The mean pain level measured by VAS was 5.13 (${\pm}2.61$). Regarding pain type, the highest pain frequency the participants experienced was deep pain (53.4%), followed by multiple pain (20.7%), intestinal pain (17.3%), and neurogenic (5.2%) and superficial pain (3.4%). 3) Regarding the factors influencing pain, the pain level was significantly affected by the depression level (P<0.01) and the opioid use (P<0.01). Conclusion, In summary, the higher the level of pain the terminally ill cancer patents had the higher the depression level as well as the opioid use. Thus, health care professionals need to continuously provide holistic care for them to die comfortably.

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