• Title/Summary/Keyword: 질의 분석

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Comparison with Growth Characteristics of Korean Melon (Cucumis melo var. makuwa) Grafted Seedlings in a Container Type Farm with LED Light and a Greenhouse under High Temperature Conditions (인공광 기반 컨테이너 육묘 시스템과 고온 조건의 플라스틱 온실 육묘에서 참외 접목묘 생육 특성 비교)

  • Wook Jin Song;Hee Woong Goo;Gyu Won Lee;Hyun Mun Kim;Kyoung Sub Park
    • Journal of Bio-Environment Control
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    • v.33 no.1
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    • pp.22-29
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    • 2024
  • This study was carried out to analyze the growth of grafted seedlings produced in a container-type farm system and a greenhouse to stably produce high-quality seedlings. For 14 days after graft-taking, the characteristics of korean melon grafted seedlings were compared by container farm and greenhouse. The container seedling system maintained a stable day/night temperature (25/20℃), relative humidity (70%), and light environment (PPFD 200µmol·m-2·s-1, photoperiod (16/8h). The difference between day and night temperature (DIF) was relatively large, with a mean temperature of 28.1/15.4℃ in the high-temperature greenhouse. Plant height of the korean melon seedling was longer in the greenhouse than in the closed seedling system, and the average SPAD value was 30.5 and 41.1 in the greenhouse and closed seedling system, respectively. To calculate the compactness of the graft seedlings, the shoot dry weight was divided by the plant height, and the value was 44.9±2.64 mg/cm and 24.4±1.56 mg/cm in the closed seedling system and the greenhouse treatment, respectively, 7 days after graft-taking. To produce high-quality seedlings during high-temperature or low-photo periods, it will be necessary to analyze the key factors that affect growth characteristics and transplanting growth and to verify the effects of the closed seedling system based on post-transplanting growth and yield.

The effect of adult learners' motivation to participate in hair education and program satisfaction on lifelong learning happiness index (성인학습자의 헤어교육 참여동기와 프로그램 만족도가평생학습 행복지수에 미치는 영향)

  • Lim Soon Ja
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.5
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    • pp.367-372
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    • 2024
  • It was intended to explore the relationship between motivation for participation in hair education, program satisfaction, and lifelong learning happiness index for adult learners at the Lifelong Education Center, and to provide basic data for revitalizing lifelong education programs. Today, universities have conditions as a comprehensive educational institution with practicality that can meet various and high-quality lifelong educational needs. The university-affiliated Lifelong Education Center plays a role in ensuring the right to learn for all citizens as well as fulfilling the social service function and greatly expanding educational opportunities, which is one of the essential functions of universities, by making good use of the excellent transfer material resources of universities. Adults should now seek professional self-identity through retraining, and respond flexibly to various social situations such as increasing roles, expanding responsibility, and uncertainty in the job and employment structure toward professional socialization in the professional world The subject of the study was to collect data by distributing 90 questionnaires to adult learner hair education subjects in G area, and 85 copies were finally used for SPSS 26.0 for Windows analysis, excluding questionnaires with insufficient responses. The survey period was from November 1 to December 27, 2023. First, it was found that adult learners' motivation to participate in hair education has an effect on the lifelong learning happiness index. Second, it was found that adult learners' satisfaction with the program of hair care workers has an effect on the lifelong learning happiness index. Through this study, it is judged that it is necessary to understand what can maximize the high lifelong learning happiness index, and to meet the learning needs of modern people living in the age of 100, increase their potential, help them design a second life, contribute to self-realization and society, and help them have steady, self-directed lifelong learning opportunities.

Studies on the Shade Tolerance, Light Requirement, and Water Relations of Economic Tree Species(III) - Analysis of Pressure-Volume Curves on the Changes of Tissue Water Relations of Five Deciduous Hardwood Species Subjected to Artificial Shading Treatments - (주요경제수종(主要經濟樹種)의 내음성(耐陰性) 및 광선요구도(光線要求度)와 수분특성(水分特性)에 관한 연구(III) - 인공피음처리하(人工被陰處理下)에서 자라는 활엽수(闊葉樹) 5수종(樹種)의 수분특성(水分特性) 변화(變化)에 대한 P-V곡선(曲線) 분석(分析) -)

  • Choi, Jeong Ho;Kwon, Ki Won
    • Journal of Korean Society of Forest Science
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    • v.90 no.4
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    • pp.524-534
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    • 2001
  • The pressure-volume curve parameters were investigated to elucidate the effects of shading treatment on the water relations of the one year old seedlings of Betula platyphylla var. japonica, Betula schmidtii, Zelkova serrata, Acer mono and Prunes sargentii subjected to five levels of artificial shading treatments. The osmotic potentials at full turgor(${\phi}_{{\pi}o}$) measured under full sunlight changed with species and growing season in the ranges of -1.04~-1.27MPa, -1.03~-1.48MPa, -0.94~-1.44MPa in first year treatment, and -0.90~-1.37MPa, -1.05~-1.79MPa, -0.99~-1.30MPa in second year treatment in June, July, and September, respectively. The osmotic potentials at full turgor increased with increment of shading level in the ranges of -0.90~-1.79MPa in full sunlight and -0.58~-1.23MPa in nearly full shading level(E) through the growing seasons in all the species studied. The osmotic potentials at turgor loss point(${\phi}_{{\pi}p}$) measured in full sunlight changed in the ranges of -1.64~-2.11MPa, -1.67~-2.15MPa, -1.47~-2.11MPa, and -1.45~-2.04MPa, -1.30~-2.00MPa, -1.28~-2.33MPa in June, July, and September of first and second years, respectively. Most of ${\phi}_{{\pi}p}$ measurements were lower within about 0.5MPa in comparison with those of ${\phi}_{{\pi}o}$. The measurements of ${\phi}_{{\pi}p}$ also increased with increment of shading level, and the differences in ${\phi}_{{\pi}p}$ among shading levels were generally greater than those in ${\phi}_{{\pi}o}$ by species and by growing season. Most of the osmotic potentials at turgor loss point as like as at full turgor were lowered in July than in June and September. The measurements of relative water content at turgor lass point(RWCp) in full sunlight were in the similar ranges of 81~88%, 71~86%, 75~84%, and 82~87, 72~84%, 76~86% in June, July, and September of first and second years, respectively. The RWCp were a little higher in A. mono and P. sargentii than in B. platyphylla var. japonica, B. schmidtii, and Z. serrata. The RWCp also decreased from 71~88% in full sunlight to 48~77% in nearly full shading treatment with increment of shading level. Even if there were some exceptions by species or by growing season, the shading effects on the changes in some P-V parameters were distinctly observed in the present study. The change in P-V parameters following shading treatment may be presumably inferred on the changes in solute accumulation, membrane elasticity, symplasmic water volume, and so on. But much more experiments should be necessarily continued for getting detailed informations on the physiological mechanism of shading effects relating to the changes in P-V parameters.

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A Study on the Extraction Rate of Brain Tissues from a $^{99m}Tc$-HMPAO Cerebral Blood flow SPECT Examination of a Patient ($^{99m}Tc$-HMPAO 뇌혈류 SPECT 검사 시 환자에 따른 뇌조직 추출률에 대한 고찰)

  • Kim, Hwa-San;Lee, Dong-Ho;Ahn, Byeong-Pil;Kim, Hyun-Ki;Jung, Jin-Yung;Lee, Hyung-Nam;Kim, Jung-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.1
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    • pp.17-26
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    • 2012
  • Purpose: This study mainly focuses on the patients treated with chemically stable radiopharmaceutical product $^{99m}Tc$-HMPAO (d,l-hexamethylpropylene amine oxime) which yielded reduced image quality due to a decreased brain extraction rate. $^{99m}Tc$-HMPAO will be examined further to determine whether this product may be accounted as a factor for this cause. Material and Methods: From January 2010 until December 2010, out of 272 patients who were all subjected to $^{99m}Tc$-HMPAO brain blood flow SPECT scans resulting from Cerebral Infarction; 23 patients(ages $55.3{\pm}9$, 21 males, 3 females) with decreased tissue extraction rate were examined in detail. The radiopharmaceutical product $^{99m}Tc$-HMPAO was used on patients with normal brain tissue exchange rate as well as those with reduced rate in order to prove its' chemical stability. The patients' age, sex, blood pressure, existence of diabetes, drug use, current health status, known side effects from CT/MRI, examination of the patients' past SPECT before/after images were accounted to determine the factors and correlations affecting the rate of blood tissue extractions. Result: After multiple linear regression analysis, there were no unusual correlations between the 6 factors excluding sex, and before/after examination images. Male subjects showed reduced brain tissue extraction rate than the females ($p$ > 0.05) 91.3% male, 8.7% female. Wilcoxon Matched-Pairs Signed-Ranks Test was used on the before/after images which yielded a value of 0.06, which did not indicate a significant amount of difference on the 2 tests ($p$ > 0.05). As a result, the before/after images indicated similar brain tissue extraction rates, and there were variations depending on the individual patient. Conclusion: The effects of the chemically stable radiopharmaceutical product $^{99m}Tc$-HMPAO depended on the patient's personal characteristics and status, therefore was considered to be a factor in reducing brain tissue extraction rate. The related articles of $^{99m}Tc$-HMPAO cerebral blood flow SPECT speculates a cerebrovascular disease and factors resulting from portal veins, and it was not possible to pin point the exact cause of decreasing brain tissue extraction rate. However, the $^{99m}Tc$-HMPAO cerebral blood flow SPECT scan proved to be extremely useful in tracking and inspecting brain diseases, as well as offering accurate results from patients suffering from reduced brain tissue extraction rates.

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Taxonomical Classification and Genesis of Jeju Series in Jeju Island (제주도 토양인 제주통의 분류 및 생성)

  • Song, Kwan-Cheol;Hyun, Byung-Geun;Moon, Kyung-Hwan;Jeon, Seung-Jong;Lim, Han-Cheol;Lee, Shin-Chan
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.2
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    • pp.230-236
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    • 2010
  • Jeju Island is a volanic island which is located about 96 km south of Korean Peninsula. Volcanic ejecta, and volcaniclastic materials are widespread as soil parent materials throughout the island. Soils on the island have the characteristics of typical volcanic ash soils. This study was conducted to reclassify Jeju series based on the second edition of Soil Taxonomy and to discuss the formation of Jeju series in Jeju Island. Morphological properties of typifying pedon of Jeju series were investigated, and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon has dark brown (10YR 3/3) silt clay loam A horizon (0~22 cm), strong brown (7.5YR 4/6) silty clay BAt horizon (22~43 cm), brown (7.5YR 4/4) silty clay Bt1 horizon (43~80 cm), brown (7.5YR 4/6) silty clay loamBt2 horizon (80~105 cm), and brown (10YR 5/4) silty clay loam Bt3 horizon (105~150 cm). It is developed in elevated lava plain, and are derived from basalt, and pyroclastic materials. The typifying pedon contains 1.3~2.1% oxalate extractable (Al + 1/2 Fe), less than 85%phosphate retention, and higher bulk density than 0.90 Mg $m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to 150 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol. Its has 0.9% or more organic carbon in the upper 15 cm of the argillic horizon, and can be classified as Humult. It dose not have fragipan, kandic horizon, sombric horizon, plinthite, etc. in the given depths, and key out as Haplohumult. A hoizon (0~22 cm) has a fine-earth fraction with both a bulk density of 1.0 Mg $cm^{-3}$ or less, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0. Thus, it keys out as Andic Haplohumult. It has 35% or more clay at the particle-size control section, and has thermic soil temperature regime. Jeju series can be classified as fine, mixed, themic family of Andic Haplohumults, not as ashy, thermic family of Typic Hapludands. In the western, and northern coastal areas which have a relatively dry climate in Jeju Island, non Andisols are widely distributed. Mean annual precipitation increase 110 mm, and mean annual temperature decrease $0.8^{\circ}C$ with increasing elevation of 100m. In the western, and northern mid-mountaineous areas Andisols, and non Andisols are distributed simultaneously. Jeju series distributed mainly in the western and northern mid-mountaineous areas are developed as Ultisols with Andic subgroup.

Postoperative Radiation Therapy for Chest Wall Invading pT3N0 Non-small Cell Lung Cancer: Elective Lymphatic Irradiation May Not Be Necessary (흉벽을 침범한 pT3N0 비소세포폐암 환자에서 수술 후 방사선치료)

  • Park, Young-Je;Ahn, Yong-Chan;Lim, Do-Hoon;Park, Won;Kim, Kwan-Min;Kim, Jhingook;Shim, Young-Mog;Kim, Kyoung-Ju;Lee, Jeung-Eun;Kang, Min-Kyu;Nam, Hee-Rim;Huh, Seung-Jae
    • Radiation Oncology Journal
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    • v.21 no.4
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    • pp.253-260
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    • 2003
  • Purpose: No general consensus has been reached regarding the necessity of postoperative radiation therapy (PORT) and the optimal techniques of its application for patients with chest wall invasion (pT3cw) and node negative (NO) non-small cell lung cancer (NSCLC). We retrospectively analyzed the PT3cwN0 NSCLC patients who received PORT because of presumed inadequate resection margin on surgical findings. Materials and Methods: From Aug. 1994 till June 2000, 21 pT3cwN0 NSCLC patients received PORT at Samsung Medical Center; all of whom underwent curative on-bloc resection of the primary tumor plus the chest wall and regional lymph node dissection. PORT was typically stalled 3 to 4 weeks after operation using 6 or 10 MV X-rays from a linear accelerator. The radiation target volume was confined to the tumor bed plus the immediate adjacent tissue, and no regional lymphatics were included. The planned radiation dose was 54 Gy by conventional fractionation schedule. The survival rates were calculated and the failure patterns analyzed. Results: Overall survival, disease-free survival, loco-regional recurrence-free survival, and distant metastases-free survival rates at 5 years were 38.8$\%$, 45.5$\%$, 90.2$\%$, and 48.1$\%$, respectively. Eleven patients experienced treatment failure: six with distant metastases, three with intra-thoracic failures, and two with combined distant and intra-thoracic failures. Among the five patients with intra-thoracic failures, two had pleural seeding, two had in-field local failures, and only one had regional lymphatic failure in the mediastinum. No patients suffered from acute and late radiation side effects of RTOG grade 3 or higher. Conclusion: The strategy of adding PORT to surgery to improve the probability, not only of local control but also of survival, was justified, considering that local control was the most important component in the successful treatment of pT3cw NSCLC patients, especially when the resection margin was not adequate. The incidence and the severity of the acute and late side effects of PORT were markedly reduced, which contributed to improving the patients' qualify of life both during and after PORT, without increasing the risk of regional failures by eliminating the regional lymphatics from the radiation target volume.

Clinical Analysis of the Recent Results of Coronary Artery Bypass Grafting (관상동맥 우회술의 최근성적에 대한 임상적 고찰)

  • Han, Sung-Ho;Kim, Hyuck;Lee, Chul-Bum;Chung, Won-Sang;Jee, Heng-Ok;Kang, Jung-Ho;Kim, Young-Hak
    • Journal of Chest Surgery
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    • v.35 no.7
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    • pp.523-529
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    • 2002
  • Background: Previous reports present that the early results of coronary artery bypass grafting (CABG) has been improving with the accumulation of surgical experience. We conducted a retrospective analysis of the patients who received CABG to evaluate the recent results of CABG. Material and Method: Between January 1996 and August 2001, 154 patients underwent CABG at Hanyang University Hospital. There were 47 patients(group I) who were operated between 1996 and 1998, and 107 patients(group II) who were operated thereafter. The preoperative diagnosis, operative procedure, mortality, and complications were analyzed retrospectively. Result: There were 35 males and 12 females in group I, and 78 males and 29 females in group II, which shows similar ratio of sexes between the two groups. The average age of patients for group I and group II was $55.9{\pm}6.2$ years and $61.0{\pm}8.0$ years, respectively, showing a significant increase in group II(p<0.05). The average left ventricular ejection fraction(LVEF) for group I and group II was $54.6{\pm}11.8$% and $56.9{\pm}13.0$%, respectively. The number of patients who had previous MI in group I and group II were 13 patients(27.7%) and 14 patients(13.1%), respectively, which shows a significant difference (p<0.05). All procedures were performed using the cardiopulmonary bypass(CPB) and moderate systemic hypothermia. Myocardial protection was achieved using intermittent hypothermic ischemia under ventricular fibrillation state or cold crystalloid cardioplegic solution for most of group I patients, whereas cold blood cardioplegic solution was used for group II patients. The mean CPB times for group I and group II were $149.2{\pm}48.7$ minutes and $113.1{\pm}30.6$ minutes, respectively. The mean aortic cross clamp times for group I and group II were $81.3{\pm}26.5$ minutes $72.2{\pm}23.9$ minutes, respectively. These figures show that CPB and aortic cross clamp times were significantly reduced in group II(p<0.05). The use of the left internal thoracic artery(LITA) was increased from 42%(20/47) for group I to 81% (87/107) for group II. The mean number of grafts also significantly increased from $2.5{\pm}0.6$ for group I to $3.0{\pm}1.1$ for group II(p<0.05). Intra-aortic balloon pump(IABP) was applied in 7 cases in group I and 17 cases in group II. Of these, 28.6%(2/7) and 52.9%(9/17) were broadly applied preoperatively in patients with LVEF<40% or congestive heart failure. The operative mortalities for group I and II were 10.6%(5/47) and 0.9%(1/107), respectively, which shows significant decrease for group II(p.0.05). Conclusion: This report suggest that CABG using CPB can recently be performed more safely in virtue of the accumulation of surgical experience with reduction in CPB and aortic cross clamp times and improved surgical techniques and myocardial protection. And we think that the optimal treatment of patients with left ventricular dysfunction associated with congestive heart failure and the extended application of IABP, especially have contributed to the reduction of operative mortality and morbidity.

Effect of Boswellia serrata Extracts on Degenerative Osteoarthritis in vitro and in vivo Models (보스웰리아 추출물의 골관절염 억제 효과 연구)

  • Nam, Da-Eun;Kim, Ok Kyung;Shim, Tae Jin;Kim, Ji Hoon;Lee, Jeongmin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.5
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    • pp.631-640
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    • 2014
  • The inhibitory effects of Boswellia serrata (BW) extracts on degenerative osteoarthritis were investigated in primary-cultured rat cartilage cells and a monosodium-iodoacetate (MIA)-induced osteoarthritis rat model. To identify the protective effects of BW extract against $H_2O_2$ ($800{\mu}M$, 2 hr) in vitro, cell survival was measured by MTT assay. Cell survival after $H_2O_2$ treatment was elevated by BW extract at a concentration of $20{\mu}g/mL$. In addition, BW extract treatment significantly reduced and normalized the productions of pro-inflammatory factors, nuclear transcription factor ${\kappa}B$, cyclooxygenase-2, tumor necrosis factor-${\alpha}$, and interleukin-6 at a concentration of $20{\mu}g/mL$. Treatment of chondrocytes with BW extract significantly reduced 5-lipoxygenase activity and production of prostaglandin E2, especially at a concentration of $10{\sim}20{\mu}g/mL$. For the in vivo animal study, osteoarthritis was induced by intra-articular injection of MIA into knee joints of rats. Consumption of a diet containing BW extract (100 and 200 mg/kg) for 35 days significantly inhibited the development and severity of osteoarthritis in rats. To determine the genetic expression of arthritic factors in articular cartilage, real-time PCR was applied to measure matrix metalloproteinases (MMP-3, MMP-9, and MMP-13), collagen type I, collagen type II, and aggrecan, and BW extract had protective effects at a concentration of 200 mg/kg. In conclusion, BW extract was able to inhibit articular cartilage degeneration by preventing extracellular matrix degradation and chondrocyte injury. One can consider that BW extract may be a potential therapeutic treatment for degenerative osteoarthritis.

Assessment of Nutrient Intakes of Lunch Meals for the Aged Customers at the Elderly Care Facilities Through Measuring Cooking Yield Factor and the Weighed Plate Waste (조리 중량 변화 계수 및 잔반계측법을 이용한 노인복지시설 이용자의 점심식사 영양섭취평가)

  • Chang, Hye-Ja;Yi, Na-Young;Kim, Tae-Hee
    • Journal of Nutrition and Health
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    • v.42 no.7
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    • pp.650-663
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    • 2009
  • The purposes of this study were to investigate one portion size of menus served and to evaluate nutrient intake of lunch at three elderly care facility food services located in Seoul. A weighed plate method was employed to measure plate wastes and consumption of the menus served. Yield factors were calculated from cooking experiments based on standardized recipes, and were used to evaluate nutrient intake. One hundred elderly participated in this study for measuring plate waste and were asked to complete questionnaire. Nutrient analyses for the served and consumed meal were performed using CAN program. The yield factors of rice dishes after cooking are 2.4 regardless of rice dish types, 1.58 for thick soups, 0.60 to 0.70 for meat dishes, and 1.0 to 1.25 branched vegetable. Average consumption quantity of dishes were 235.97 g for rice, 248.53 g for soup, 72.83 g for meat dishes, 39.80 g for vegetables and 28.36 g for Kimchi. On average the food waste rate is 14.0%, indicating the second highest plate waste percentage of Kimchi (26.2%), and meat/fish dish (17.3%). The evaluation results of NAR (Nutrition Adequacy Ratio) showed that iron (0.12), calcium (0.64), riboflavin (0.80), and folic acid (0.97) were less than 1.0 in both male and female elderly groups, indicating significant differences of NAR among three facilities. Compared to the 1/3 Dietary Reference Intake (DRIs) for the elderly groups, nutrient intake analysis demonstrated that calcium (100%) and iron (100%), followed by riboflavin, vitamin A, and Vitamin B6 did not met of the 1/3 EAR (Estimated Average Requirement). For the nutritious meal management, a professional dietitian should be placed at the elderly care center to develop standardized recipes in consideration of yield factors and the elderly's health and nutrition status.

The Actual State and the Utilization for Dental Radiography in Korea (국내 치과방사선의 현황 및 이용 실태)

  • Shin, Gwi-Soon;Kim, You-Hyun;Lee, Bo-Ram;Kim, Se-Young;Lee, Gui-Won;Park, Chang-Seo;Park, Hyok;Chang, Kye-Yong
    • Journal of radiological science and technology
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    • v.33 no.2
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    • pp.109-120
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    • 2010
  • The purpose of this study was first to analyze the utilization of dental examination through questionnaire to develop a diagnostic reference level of patient doses for dental radiography in korea. 77 dental institutions were classified into three groups: A group for the dental hospitals of the college of dentistry (11 institutions), B group for dental hospitals (30 institutions) and C group for dental clinics (36 institutions). The results were as follows : The mean numbers of unit chairs and medical staffs were 140.2, 15.3 and 5.8 sets, 112.6, 7.3 and 1.7 dentists, 3.1, 0.5 and no one radiologic technologists, and 19.7, 12.5 and 3.3 dental hygienists in A, B and C groups, respectively. The mean numbers of dental X-ray equipments were 14.64, 3.21 and 2.19 in A, B and C groups, respectively. Intraoral dental X-ray unit was used the most, the following equipments were panoramic, cephalometric, and cone-beam CT units. The most used X-ray imaging system was also digital system (above 50%) in all three groups. Insight dental film (Kodak, USA) having high sensitivity was routinely used for periapical radiography. The automatic processor was not used in many dental institutions, but the film-holding device was used in many dental institutions. The utilization rates of PACS in A, B and C groups were 90.9%, 83.3% and 16.7% respectively, and the PACS software program was used the most PiView STAR (Infinitt, Korea). The annual mean number of radiographic cases in one dental institution in 2008 for A group was 6.8 times and 21.2 times more than those for B and C groups, and periapical and panoramic radiographs were taken mostly. Tube voltage (kVp) and tube current (mA) for periapical radiography were similar in all three groups, but exposure time in C group was 12.0 times and 3.5 times longer than those in B and C groups. The amount of radiation exposure in C group, in which dental hygienists take dental radiographs, was more than those in other groups. The exposure parameters for panoramic radiography were similar in all three groups. In conclusion, the exposure parameters in dental radiography should be determined with reference level, not past experiences. Use of automatic processor and film-holding devices reduces the radiation exposure in film system. The quality assurance of dental equipments are necessary for the reduction of the patient dose and the improvement of X-ray image quality.