• Title/Summary/Keyword: Normal values

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Evaluation of sleep quality and stress response in patients requiring dental prosthetic treatment (치과보철치료를 요하는 환자에서의 수면질과 스트레스 반응 평가)

  • Jeon, Hye-Mi;Jung, Kyoung-Hwa;Choi, Na-Rae;Song, Jae-Min;Lee, So-Hyoun;Kim, So-Yeun
    • The Journal of Korean Academy of Prosthodontics
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    • v.59 no.2
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    • pp.181-189
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    • 2021
  • Purpose: The purpose of this study is to investigate the stress response and sleep state of the new patients who visit the hospital for prosthodontic treatment due to tooth loss to make reference to further treatment direction. Materials and methods: Examinations, consultations, and surveys were conducted on 236 patients (94 males, 142 females, and 24-86 years old), who newly registered at the department of prosthodontics at Pusan national university hospital, for 2 years from 2018. The number of remaining teeth, edentulous arch, possibility of mastication, and future prosthetic treatment directions were recorded. The visual analogue scale (VAS), stress response inventory (SRI) and Insomnia severity index (ISI) were used as tools to measure patient's subjective discomfort, stress response, and sleep status. Results: Among the entire prosthodontic patient group, the average value of 'fatigue' was significantly higher among the 7 items of SRI, and the value of 'aggression' was significantly lower (P<.001). There are a significant difference between the edentulous and full dentition in the oral discomfort value measured by VAS (P=.004). In cases where less than 20 teeth remain, mastication is impossible, and patients who are planning treatment with removable prostheses, VAS value and 'depression' and 'fatigue' values in SRI were higher than those in the reverse case (P<.05). The patients showed severe level in VAS value have high value of 'tension', 'somatization', 'depression', 'fatigue'and 'frustration'in SRI than non-serious patients (P<.05). Clinical insomnia occurred in 11.4% of all patients, and women had significantly lower sleep quality than men (P=.044). Patients with insomnia showed significantly higher scores on the VAS value and all 7 SRI items than those of normal sleepers (P<.05). Conclusion: The new prosthetics had high 'fatigue' value among the 7 items of SRI. The oral condition, number of residual teeth and mastication function and clinical insomnia affected oral discomfort and the stress response.

A study on the effect of collimator angle on PAN-Pelvis volumetric modulated arc therapy (VMAT) including junction (접합부를 포함한 PAN-전골반암 VMAT 치료 계획 시 콜리메이터 각도의 영향에 관한 고찰)

  • Kim, Hyeon Yeong;Chang, Nam Jun;Jung, Hae Youn;Jeong, Yun Ju;Won, Hui Su;Seok, Jin Yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.32
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    • pp.61-71
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    • 2020
  • Purpose: To investigate the effect of collimator angle on plan quality of PAN-Pelvis Multi-isocenter VMAT plan, dose reproducibility at the junction and impact on set-up error at the junction. Material and method: 10 adult patients with whole pelvis cancer including PAN were selected for the study. Using Trubeam STx equipped with HD MLC, we changed the collimator angle to 20°, 30°, and 45° except 10° which was the default collimator angle in the Eclipse(version 13.7) and all other treatment conditions were set to be the same for each patient and four plans were established also. To evaluate these plans, PTV coverage, coverage index(CVI) and homogeneity index (HI) were compared and clinical indicators for each treatment sites in normal tissues were analyzed. To evaluate dose reproducibility at the junction, the absolute dose was measured using a Falmer type ionization chamber and dose changes at the junction were evaluated by moving the position of the isocenter in and out 1~3mm and setting up the virtual volume at the junction. Result: CVI mean value was PTV-45 0.985±0.004, PTV-55 0.998±0.003 at 45° and HI mean value was PTV-45 1.140±0.074, and PTV-55 1.031±0.074 at 45° which were closest to 1. V20Gy of the kidneys decreased by 9.66% and average dose of bladder and V30 decreased by 1.88% and 2.16% at 45° compared to 10° for the critical organs. The dose value at the junction of the plan and the actual measured were within 0.3% and within tolerance. At the junction, due to set-up error the maximum dose increased to 14.56%, 9.88%, 8.03%, and 7.05%, at 10°, 20°, 30°, 45°, and the minimum dose decreased to 13.18%, 10.91%, 8.42%, and 4.53%, at 10°, 20°, 30°, 45° Conclusion: In terms of CVI, HI of PTV and critical organ protection, overall improved values were shown as the collimator angle increased. The impact on set-up error at the junction by collimator angle decreased as the angle increased and it will help improve the anxiety about the set up error. In conclusion, the collimator angle should be recognized as a factor that can affect the quality of the multi-isocenter VMAT plan and the dose at the junction, and be careful in setting the collimator angle in the treatment plan.

Correlation Analysis of Inspection Results and ATP Bioluminescence Assay for Verification of Hygiene Status at 5 Star Hotels in Korea (국내 주요 5성급 호텔의 위생실태 조사와 ATP 결과의 상관분석 평가 연구)

  • Kim, Bo-Ram;Lee, Jung-A;Ha, Sang-Do
    • Journal of Food Hygiene and Safety
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    • v.36 no.1
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    • pp.42-50
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    • 2021
  • Along with the rapid growth of the food service industry, food safety requirements and hygiene are increasing in importance in restaurants and hotels. Accordingly, there is a need for quick and practical monitoring techniques to determine hygiene status in the field. In this study, we investigated 5 domestic 5-star hotels specifically, personal hygiene (hands of workers), cooking utensils (knife, cutting board, food storage container, slicing machine blade, ice-maker scoop) and other facilities (refrigerator handle, sink). In addition, we examined the hygiene management status of customer contact points (tongs for buffet, etc.) to derive the correlation between the ATP values as a, a verification method. As a result of our five-hotel survey, we found that cooking utensils and personal hygiene were relatively sanitary compared to other inspection items (cookware 92.2%, personal hygiene 91.4%, facilities and equipment 76.19%, customer contact items 88.6%). According to our ATP-based mothod, kitchen utensils (51 ± 45 RLU/25㎠) were relatively clean compared to other with facilities and equipment (167 ± 123 RLU/25㎠). In the present study, we also evaluated the usefulness of the ATP bioluminescence method for monitoring surface hygiene at hotel restaurants. After correlation analysis of surveillance of hygienic status points and ATP assay, most results showed negative and high correlation (-0.64--0.89). Our ATP assay (92 ± 67 RLU/25㎠) of each item after cleaning showed signigicantly reduced results compared to the ATP assay (1020 ± 1254 RLU/25㎠) for normal status, thereby indicating its suitability as a tool to verify the validity of cleaning. By our results, ATP bioluminescence could be used as an effective tool for visual numerical evaluation of invisible contaminants.

Study on dose comparison using X-Jaw split in VMAT treatment planning for left breast cancer including supraclavicular lymph nodes. (쇄골 상부 림프절을 포함하는 왼쪽 유방암의 VMAT 치료계획시 X-Jaw split을 이용한 선량비교에 관한 연구)

  • Kim, Hak Jun;Lee, Yang Hoon;Min, Jae Soon
    • The Journal of Korean Society for Radiation Therapy
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    • v.33
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    • pp.137-144
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    • 2021
  • Purpose : The usability of X-Jaw split VMAT was evaluated by comparative analysis of the dose distribution between the treatment plan divided by X-Jaw and Full field VMAT treatment plan in left breast cancer treatment including supraclavicular lymph nodes. Materials and Methods : 10 patients with left breast cancer, including supraclavicular lymph nodes, were simulated using vacuum cushion, and 2 Full field Arc VMAT and 4 X-Jaw split Arc VMAT were planned The treatment plan was designed to include more than 95% of the Planning Target Volume (PTV) and to be minimally irradiated in the surrounding Organ at risk (OAR). Dose analysis of PTV and OAR was performed through dose volume histogram (DVH). Results : The Full field VMAT treatment plan and the X-Jaw split VMAT treatment plan of 10 patients were expressed as average values and compared. The difference between the two treatment plans was not large, with a Conformity index (CI) of 1.05±0.04, 1.04±0.03, and a Homogeneity index (HI) of 1.07±0.008, 1.07±0.009. For OAR, V5 in the left lung is 56.1±6.50%, 50.4±6.30%, and V20 is 20.0±4.15%, 13.52±3.61%. Compared to Full field VMAT, V5 decreased by 10.0% V20 by 32.6% in X-Jaw split VMAT. The V30 of the heart is 3.68±1.85%, 2.23±1.52%, and the Mean dose is 8.93±1.65 Gy, 7.67±1.52 Gy. In the X-Jaw split VMAT, V30 decreased by 39.3% and the Mean dose decreased by 14.1%. The left lung and heart, which are normal tissues, were found to have a statistical significance of that p-value is less than 0.05. Conclusion : In the case of left breast cancer treatment, which includes Supraclavicular lymph nodes with a large PTV volume and a length of X Jaw of 15 cm or more, the X-Jaw split VMAT shows improved dose distribution, which can reduce radiation dose of OAR such as lungs and heart, while maintaining similar PTV coverage with HI and CI equivalent to Full field VMAT. It is thought to be effective in reducing radiation complications.

THE EFFECT OF THE REPEATABILITY FILE IN THE NIRS EATTY ACIDS ANALYSIS OF ANIMAL EATS

  • Perez Marin, M.D.;De Pedro, E.;Garcia Olmo, J.;Garrido Varo, A.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.4107-4107
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    • 2001
  • Previous works have shown the viability of NIRS technology for the prediction of fatty acids in Iberian pig fat, but although the resulting equations showed high precision, in the predictions of new samples important fluctuations were detected, greater with the time passed from calibration development to NIRS analysis. This fact makes the use of NIRS calibrations in routine analysis difficult. Moreover, this problem only appears in products like fat, that show spectrums with very defined absorption peaks at some wavelengths. This circumstance causes a high sensibility to small changes of the instrument, which are not perceived with the normal checks. To avoid these inconveniences, the software WinISI 1.04 has a mathematic algorithm that consist of create a “Repeatability File”. This file is used during calibration development to minimize the variation sources that can affect the NIRS predictions. The objective of the current work is the evaluation of the use of a repeatability file in quantitative NIRS analysis of Iberian pig fat. A total of 188 samples of Iberian pig fat, produced by COVAP, were used. NIR data were recorded using a FOSS NIRSystems 6500 I spectrophotometer equipped with a spinning module. Samples were analysed by folded transmission, using two sample cells of 0.1mm pathlength and gold surface. High accuracy calibration equations were obtained, without and with repeatability file, to determine the content of six fatty acids: miristic (SECV$\sub$without/=0.07% r$^2$$\sub$without/=0.76 and SECV$\sub$with/=0.08% r$^2$$\sub$with/=0.65), Palmitic (SECV$\sub$without/=0.28 r$^2$$\sub$without/=0.97 and SECV$\sub$with/=0.24% r$^2$$\sub$with/=0.98), palmitoleic (SECV$\sub$without/=0.08 r$^2$$\sub$without/=0.94 and SECV$\sub$with/=0.09% r$^2$$\sub$with/=0.92), Stearic (SECV$\sub$without/=0.27 r$^2$$\sub$without/=0.97 and SECV$\sub$with/=0.29% r$^2$$\sub$with/=0.96), oleic (SECV$\sub$without/=0.20 r$^2$$\sub$without/=0.99 and SECV$\sub$with/=0.20% r$^2$$\sub$with/=0.99) and linoleic (SECV$\sub$without/=0.16 r$^2$$\sub$without/=0.98 and SECV$\sub$with/=0.16% r$^2$$\sub$with/=0.98). The use of a repeatability file like a tool to reduce the variation sources that can disturbed the prediction accuracy was very effective. Although in calibration results the differences are negligible, the effect caused by the repeatability file is appreciated mainly when are predicted new samples that are not in the calibration set and whose spectrum were recorded a long time after the equation development. In this case, bias values corresponding to fatty acids predictions were lower when the repeatability file was used: miristic (bias$\sub$without/=-0.05 and bias$\sub$with/=-0.04), Palmitic (bias$\sub$without/=-0.42 and bias$\sub$with/=-0.11), Palmitoleic (bias$\sub$without/=-0.03 and bias$\sub$with/=0.03), Stearic (bias$\sub$without/=0.47 and bias$\sub$with/=0.28), oleic (bias$\sub$without/=0.14 and bias$\sub$with/=-0.04) and linoleic (bias$\sub$without/=0.25 and bias$\sub$with/=-0.20).

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Evaluation of Anti-wrinkle Effect of Peanut Shell Extract and Stability of the Extract in Cosmetic Products (땅콩 겉껍질 추출물의 주름개선 효능 및 화장품 제형에서 추출물의 안정성 평가)

  • Narae Han;Jin Young Lee;Mihyang Kim;Eun Young Choi;Bong-Jeun An;Yu-Young Lee;Moon Seok Kang;Hyun-Joo Kim
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.3
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    • pp.203-212
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    • 2023
  • This study was conducted to investigate the possibility of peanut shell, a by-product of peanut, as a functional cosmetic ingredient. Peanut shell extract showed high antioxidant activity with IC50 values of 75.00, 46.33, and 472.83 ㎍/mL for DPPH and ABTS radical scavenging and SOD-like activity, respectively. Furthermore, peanut shell extract was efficiently decreased the MMP-1 and MMP-3 protein level in the UVB treated-HaCaT cell and maintained procollagen protein level similar to normal control. Similar to anti-wrinkle related protein expression assay, the IC50 value of elastase and collagnease inhibition in peanut shell extract was lower as 0.30 and 0.09 mg/mL, respectively, than that of the positive control. Additionally, eriodictyol and luteolin, which are isolated from peanut shell extract, showed 53.8 and 98.0% elastase inhibition rate, respectively, and 60.1 and 72.5% collagenase inhibition rate, respectively, at a concentration of 0.1 mg/mL. Thus, luteolin was assumed to be the effective ingredient for wrinkle inhibition in peanut shell extract. As a result of stability evaluation of lotion and cream formulations containing peanut shell extract, it was confirmed to be a stable formulation with no significant changes. Therefore, it is considered that peanut shell extract can be applied as a cosmetic ingredient for wrinkle inhibition.

Antioxidant Activity of Tea Made from Korean Mountain-Cultivated Ginseng Leaves and its Influence on Lipid Metabolism (장뇌삼 엽차의 항산화활성 및 지질대사에 미치는 영향)

  • Bae, Man-Jong;Kim, Soo-Jung;Ye, Eun-Ju;Nam, Hak-Sik;Park, Eun-Mi
    • Journal of the Korean Society of Food Culture
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    • v.24 no.1
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    • pp.77-83
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    • 2009
  • This study was conducted to investigate the chemical composition and biological function of tea made from mountain-cultivated ginseng leaves. The antioxidant activities of tea made from mountain-cultivated ginseng leaves were determined by measuring their electron-donating ability based on their DPPH and nitrite-scavenging ability. The electron-donating abilities of tea made from mountain-cultivated ginseng leaves (500 and 1,000 ppm) as determined by DPPH assay were 45.6 and 85.1%, respectively. The nitrite scavenging ability of tea made from mountain-cultivated ginseng leaves (500 and 1,000 ppm) at pH 6.0 were 32.8 and 51.4%, respectively. Furthermore, the nitrite scavenging activity increased in a dose-dependent manner at all pH values. The effects of tea made from mountain-cultivated ginseng leaves on Male Sprague-Dawley rats were also evaluated. To accomplish this, the rats were divided into three groups (A: normal diet group, B: high fat diet group and C: high fat diet supplemented with tea made from mountain-cultivated ginseng leaves group). The anti-obesity effects of tea made from mountain-cultivated ginseng leaves were then evaluated. The serum total lipid, total cholesterol and triglyceride contents in C group were lower than those of B group; however, these differences were not statistically significant. The HDL-cholesterol content was significantly higher in the C group than in the other groups. Taken together the results of this study suggest that tea made from mountain-cultivated ginseng leaves possesses antioxidant activity and improves lipid metabolism.

Determining Spatial and Temporal Variations of Surface Particulate Organic Carbon (POC) using in situ Measurements and Remote Sensing Data in the Northeastern Gulf of Mexico during El $Ni\tilde{n}o$ and La $Ni\tilde{n}a$ (현장관측 및 원격탐사 자료를 이용한 북동 멕시코 만에서 El $Ni\tilde{n}o$와 La $Ni\tilde{n}a$ 기간 동안 표층 입자성 유기탄소의 시/공간적 변화 연구)

  • Son, Young-Baek;Gardner, Wilford D.
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.15 no.2
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    • pp.51-61
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    • 2010
  • Surface particulate organic carbon (POC) concentration was measured in the Northeastern Gulf of Mexico on 9 cruises from November 1997 to August 2000 to investigate the seasonal and spatial variability related to synchronous remote sensing data (Sea-viewing Wide Field-of-view Sensor (SeaWiFS), sea surface temperature (SST), sea surface height anomaly (SSHA), and sea surface wind (SSW)) and recorded river discharge data. Surface POC concentrations have higher values (>100 $mg/m^3$) on the inner shelf and near the Mississippi Delta, and decrease across the shelf and slope. The inter-annual variations of surface POC concentrations are relatively higher during 1997 and 1998 (El Nino) than during 1999 and 2000 (La Nina) in the study area. This phenomenon is directly related to the output of Mississippi River and other major rivers, which associated with global climate change such as ENSO events. Although highest river runoff into the northern Gulf of Mexico Coast occurs in early spring and lowest flow in late summer and fall, wide-range POC plumes are observed during the summer cruises and lower concentrations and narrow dispersion of POC during the spring and fall cruises. During the summer seasons, the river discharge remarkably decreases compared to the spring, but increasing temperature causes strong stratification of the water column and increasing buoyancy in near-surface waters. Low-density plumes containing higher POC concentrations extend out over the shelf and slope with spatial patterns and controlled by the Loop Current and eddies, which dominate offshore circulation. Although river discharge is normal or abnormal during the spring and fall seasons, increasing wind stress and decreasing temperature cause vertical mixing, with higher surface POC concentrations confined to the inner shelf.

Analysis of media trends related to spent nuclear fuel treatment technology using text mining techniques (텍스트마이닝 기법을 활용한 사용후핵연료 건식처리기술 관련 언론 동향 분석)

  • Jeong, Ji-Song;Kim, Ho-Dong
    • Journal of Intelligence and Information Systems
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    • v.27 no.2
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    • pp.33-54
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    • 2021
  • With the fourth industrial revolution and the arrival of the New Normal era due to Corona, the importance of Non-contact technologies such as artificial intelligence and big data research has been increasing. Convergent research is being conducted in earnest to keep up with these research trends, but not many studies have been conducted in the area of nuclear research using artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. This study was conducted to confirm the applicability of data science analysis techniques to the field of nuclear research. Furthermore, the study of identifying trends in nuclear spent fuel recognition is critical in terms of being able to determine directions to nuclear industry policies and respond in advance to changes in industrial policies. For those reasons, this study conducted a media trend analysis of pyroprocessing, a spent nuclear fuel treatment technology. We objectively analyze changes in media perception of spent nuclear fuel dry treatment techniques by applying text mining analysis techniques. Text data specializing in Naver's web news articles, including the keywords "Pyroprocessing" and "Sodium Cooled Reactor," were collected through Python code to identify changes in perception over time. The analysis period was set from 2007 to 2020, when the first article was published, and detailed and multi-layered analysis of text data was carried out through analysis methods such as word cloud writing based on frequency analysis, TF-IDF and degree centrality calculation. Analysis of the frequency of the keyword showed that there was a change in media perception of spent nuclear fuel dry treatment technology in the mid-2010s, which was influenced by the Gyeongju earthquake in 2016 and the implementation of the new government's energy conversion policy in 2017. Therefore, trend analysis was conducted based on the corresponding time period, and word frequency analysis, TF-IDF, degree centrality values, and semantic network graphs were derived. Studies show that before the 2010s, media perception of spent nuclear fuel dry treatment technology was diplomatic and positive. However, over time, the frequency of keywords such as "safety", "reexamination", "disposal", and "disassembly" has increased, indicating that the sustainability of spent nuclear fuel dry treatment technology is being seriously considered. It was confirmed that social awareness also changed as spent nuclear fuel dry treatment technology, which was recognized as a political and diplomatic technology, became ambiguous due to changes in domestic policy. This means that domestic policy changes such as nuclear power policy have a greater impact on media perceptions than issues of "spent nuclear fuel processing technology" itself. This seems to be because nuclear policy is a socially more discussed and public-friendly topic than spent nuclear fuel. Therefore, in order to improve social awareness of spent nuclear fuel processing technology, it would be necessary to provide sufficient information about this, and linking it to nuclear policy issues would also be a good idea. In addition, the study highlighted the importance of social science research in nuclear power. It is necessary to apply the social sciences sector widely to the nuclear engineering sector, and considering national policy changes, we could confirm that the nuclear industry would be sustainable. However, this study has limitations that it has applied big data analysis methods only to detailed research areas such as "Pyroprocessing," a spent nuclear fuel dry processing technology. Furthermore, there was no clear basis for the cause of the change in social perception, and only news articles were analyzed to determine social perception. Considering future comments, it is expected that more reliable results will be produced and efficiently used in the field of nuclear policy research if a media trend analysis study on nuclear power is conducted. Recently, the development of uncontact-related technologies such as artificial intelligence and big data research is accelerating in the wake of the recent arrival of the New Normal era caused by corona. Convergence research is being conducted in earnest in various research fields to follow these research trends, but not many studies have been conducted in the nuclear field with artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. The academic significance of this study is that it was possible to confirm the applicability of data science analysis technology in the field of nuclear research. Furthermore, due to the impact of current government energy policies such as nuclear power plant reductions, re-evaluation of spent fuel treatment technology research is undertaken, and key keyword analysis in the field can contribute to future research orientation. It is important to consider the views of others outside, not just the safety technology and engineering integrity of nuclear power, and further reconsider whether it is appropriate to discuss nuclear engineering technology internally. In addition, if multidisciplinary research on nuclear power is carried out, reasonable alternatives can be prepared to maintain the nuclear industry.

Comparison of Single-Breath and Intra-Breath Method in Measuring Diffusing Capacity for Carbon Monoxide of the Lung (일산화탄소 폐확산능검사에서 단회호흡법과 호흡내검사법의 비교)

  • Lee, Jae-Ho;Chung, Hee-Soon;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.4
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    • pp.555-568
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    • 1995
  • Background: It is most physiologic to measure the diffusing capacity of the lung by using oxygen, but it is so difficult to measure partial pressure of oxygen in the capillary blood of the lung that in clinical practice it is measured by using carbon monoxide, and single-breath diffusing capacity method is used most widely. However, since the process of withholding the breath for 10 seconds after inspiration to the total lung capacity is very hard to practice for patients who suffer from cough, dyspnea, etc, the intra-breath lung diffusing capacity method which requires a single exhalation of low-flow rate without such process was devised. In this study, we want to know whether or not there is any significant difference in the diffusing capacity of the lung measured by the single-breath and intra-breath methods, and if any, which factors have any influence. Methods: We chose randomly 73 persons without regarding specific disease, and after conducting 3 times the flow-volume curve test, we selected forced vital capacity(FVC), percent of predicted forced vital capacity, forced expiratory volume within 1 second($FEV_1$), percent of forced expiratory volume within 1 second, the ratio of forced expiratory volume within 1 second against forced vital capacity($FEV_1$/FVC) in test which the sum of FVC and $FEV_1$ is biggest. We measured the diffusing capacity of the lung 3 times in each of the single-breath and intra-breath methods at intervals of 5 minutes, and we evaluated which factors have any influence on the difference of the diffusing capacity of the lung between two methods[the mean values(ml/min/mmHg) of difference between two diffusing capacity measured by two methods] by means of the linear regression method, and obtained the following results: Results: 1) Intra-test reproducibility in the single-breath and intra-breath methods was excellent. 2) There was in general a good correlation between the diffusing capacity of the lung measured by a single-breath method and that measured by the intra-breath method, but there was a significant difference between values measured by both methods($1.01{\pm}0.35ml/min/mmHg$, p<0.01) 3) The difference between the diffusing capacity of the lung measured by both methods was not correlated to FVC, but was correlated to $FEV_1$, percent of $FEV_1$, $FEV_1$/FVC and the gradient of methane concentration which is an indicator of distribution of ventilation, and it was found as a result of the multiple regression test, that the effect of $FEV_1$/FVC was most strong(r=-0.4725, p<0.01) 4) In a graphic view of the difference of diffusing capacity measured by single-breath and intra-breath method and $FEV_1$/FVC, it was found that the former was divided into two groups in section where $FEV_1$/FVC is 50~60%, and that there was no significant difference between two methods in the section where $FEV_1$/FVC is equal or more than 60% ($0.05{\pm}0.24ml/min/mmHg$, p>0.1), but there was significant difference in the section, less than 60%($-4.5{\pm}0.34ml/min/mmHg$, p<0.01). 5. The diffusing capacity of the lung measured by the single-breath and intra-breath method was the same in value($24.3{\pm}0.68ml/min/mmHg$) within the normal range(2%/L) of the methane gas gradient, and there was no difference depending on the measuring method, but if the methane concentration gradients exceed 2%/L, the diffusing capacity of the lung measured by single-breath method became $15.0{\pm}0.44ml/min/mmHg$, and that measured by intra-breath method, $11.9{\pm}0.51ml/min/mmHg$, and there was a significant difference between them(p<0.01). Conclusion: Therefore, in case where $FEV_1$/FVC was less than 60%, the diffusing capacity of the lung measured by intra-breath method represented significantly lower value than that by single-breath method, and it was presumed to be caused largely by a defect of ventilation-distribution, but the possibility could not be excluded that the diffusing capacity of the lung might be overestimated in the single-breath method, or the actual reduction of the diffusing capacity of the lung appeared more sensitively in the intra-breath method.

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