• Title/Summary/Keyword: Reliability Distribution

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An Experimental Method for the Scatter Correction of MV Images Using Scatter to Primary Ratios (SPRs) (산란선 대 일차선비(SPR)를 이용한 MV 영상의 산란 보정을 위한 실험적 방법)

  • Jeon, Hosang;Park, Dahl;Lee, Jayeong;Nam, Jiho;Kim, Wontaek;Ki, Yongkan;Kim, Donghyun;Lee, Ju Hye;Kim, Dongwon
    • Progress in Medical Physics
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    • v.25 no.3
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    • pp.143-150
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    • 2014
  • In general radiotherapy, mega-voltage (MV) x-ray images are widely used as the unique method to verify radio-therapeutic fields. But, the image quality of MV images is much lower than that of kilo-voltage x-ray images due to scatter interactions. Since 1990s, studies for the scatter correction have performed with digital-based MV imaging systems. In this study, a novel method for the scatter correction is suggested using scatter to primary ratio (SPR), instead of conventional methods such as digital image processing or scatter kernel calculations. We measured two MV images with and without a solid water phantom describing a patient body with given imaging conditions, and calculated un-attenuated ratios. Then, we obtained SPR distributions for the scatter correction. For experimental validation, a line-pair (LP) phantom using several Al bars and a clinical pelvis MV image was used. As the result, scatter signals of the LP phantom image were successfully reduced so that original density distribution of the phantom was restored. Moreover, image contrast values increased after SPR correction at all ROIs of the clinical image. The mean value of increases was 48%. The SPR correction method suggested in this study has high reliability because it is based on actually measured data. Also, this method can be easily adopted in clinics without additional cost. We expected that the SPR correction can be an effective method to improve the quality of MV image guided radiotherapy.

Proficiency Testing for the HPLC Analysis of Azoxystrobin, Imidacloprid and Methabenzthiazuron Residues in Soil (HPLC를 이용한 아족시스트로빈과 이미다클로프리드, 메타벤즈티아주론의 토양 잔류분석 숙련도시험)

  • Kim, Chan-Sub;Son, Kyeong-Ae;Gil, Geun-Hwan;Im, Geon-Jae
    • The Korean Journal of Pesticide Science
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    • v.19 no.3
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    • pp.218-229
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    • 2015
  • The proficiency testing for the residue laboratories of pesticide registration was conducted in order to improve the reliability and the ability for pesticide residue analysis. On November 2012 the testing was carried out using the soil collected and kept as the moistened state for five years, which was expected to very low residue levels of pesticides. The soil was fortified with azoxystrobin, imidacloprid and methabenzthiazuron in a manner similar to prepare soil samples for indoor soil degradation test, and then sub-samples were prepared for the distribution to participants. Some of them were randomly selected for confirm of homogeneity and to ensure the stability of samples at room temperature. Samples were consisted of two soils treated as different levels, one of which was used to the assessment and another used to confirm. In addition, provided three standard solutions, respectively concentration of 10 mg/L, and untreated soil. Forty eight institutions submitted results. The medians of results were used as the assigned values for pesticide residues. Fitness for purpose standard deviation of proficiency test was calculated by applying 20% RSD as the coefficient of variation allowed in the soil residue test. Z-score was applied for evaluation of individual pesticides, and the average of the absolute value of the Z-score for the overall assessment of pesticides. Laboratories evaluated the absolute value of the Z-score less than 2 to fit the case of azoxystrobin were 48, imidacloprid and methabenzthiazuron 46.

A Comparative Study of the Function of Nursing Management According to the Position of Nursing Department in Hospital Organization (병원조직내 간호부서의 위치에 따른 간호관리 기능 비교 연구)

  • Lee, Kum-Ja
    • Journal of Korean Academy of Nursing Administration
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    • v.4 no.2
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    • pp.387-403
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    • 1998
  • These days our nation is standing on tiptoe of welfare nation. so hospital in authority have done reformation to provide quality medical services. This effective nursing work to provide quality nursing by keeping pace with the reformation of management of hospital for quality medical function might be well said to be depending on the degree of function of nursing management of nursing department. This essay has been aimed to prepare the data to build the position of nursing organization which can elevate the quality of nursing by clarifying the difference of the degree of the function of nursing management according to the position of nursing department in hospital organization. 135 nurses of 1 general hospital in Seoul which has independent nursing organization of the hospitals of over 600 beds and 155 nurses of 1 general hospital in Seoul which has the nursing organization under the management of medical department have been the objects of this study. The tool of Yoon. Young Ae(1988) has been used by having it amended and complemented and the degree of reliability of the tool was resulted in Cronbach's Alpha .9155. The collected data have been analysed by SPSS program as mean. frequency, chi-square. t-test. F-test(ANOVA) and the results are as the follows; 1. Compared result of general characteristics of the two groups by $x^2$-test showed statistically significant difference between religion ($x^2$=10.375, p=.015) and educational background($x^2$=51.222. p=.000) 2. The t-test aimed to compare the degree of function of nursing management according to the position of nursing department is as the below: Compared result of the degree of the function of nursing management according to the areas has shown higher point in independent type(M=3.22) than in the type under the management of medical department(M=2.85) in the personnel and administrative activities of nursing department. the standard and regulation of nursing duty also showed higher point in independent than in the type under the management of medical department (M=3.37) and the education of nursing showed higher point in independent type(M=3.53) than in the type under the management of medical department(M=3.19) and the evaluation of nursing quality has shown higher point in independent type(M=3.33) than in the type under the management of medical department(M=3.05), The area which showed the highest difference of the degree of the function of nursing management between the two organizations was in the activities of personnel and administration management of nursing department (independent type M=3.22. the type under the management of medical department(M=2.85). The degree of function of general nursing management showed higher in independent type nursing organization than in the type under the management of medical department by 3.41 in independent type and 3.11 in the type under the management of medical department. The items which showed the lowest degree of function of nursing management of both organizations have been suitable nursing man power and distribution and the reflection of the opinion of nursing department. In conclusion. the degree of function of nursing management to be able to provide quality nursing for the hospital goal of quality medical works showed visibly higher in independent nursing organization than in the nursing organization under the management of medical department. Therefore it is desirable for the hospital to operate the nursing department in hospital organization by independent type rather than the type under the management of medical department and the chief of nursing department of the nursing organization of the type under the management of medical department should make effort to reform its structure to be able to establish the position of performing independent nursing management. And also the chief of the nursing organization of independent type should endeavor to build substantial independent type organization more than ever under the viewpoint of securing suitable nursing man power and the low degree of management in the reflection of the opinion of nursing department.

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A Simple Method Using a Topography Correction Coefficient for Estimating Daily Distribution of Solar Irradiance in Complex Terrain (지형보정계수를 이용한 복잡지형의 일 적산일사량 분포 추정)

  • Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.1
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    • pp.13-18
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    • 2009
  • Accurate solar radiation data are critical to evaluate major physiological responses of plants. For most upland crops and orchard plants growing in complex terrain, however, it is not easy for farmers or agronomists to access solar irradiance data. Here we suggest a simple method using a sun-slope geometry based topographical coefficient to estimate daily solar irradiance on any sloping surfaces from global solar radiation measured at a nearby weather station. An hourly solar irradiance ratio ($W_i$) between sloping and horizontal surface is defined as multiplication of the relative solar intensity($k_i$) and the slope irradiance ratio($r_i$) at an hourly interval. The $k_i$ is the ratio of hourly solar radiation to the 24 hour cumulative radiation on a horizontal surface under clear sky conditions. The $r_i$ is the ratio of clear sky radiation on a given slope to that on a horizontal reference. Daily coefficient for slope correction is simply the sum of $W_i$ on each date. We calculated daily solar irradiance at 8 side slope locations circumventing a cone-shaped parasitic volcano(c.a., 570m diameter for the bottom circle and 90m bottom-to-top height) by multiplying these coefficients to the global solar radiation measured horizontally. Comparison with the measured slope irradiance from April 2007 to March 2008 resulted in the root mean square error(RMSE) of $1.61MJ\;m^{-2}$ for the whole period but the RMSE for April to October(i.e., major cropping season in Korea) was much lower and satisfied the 5% error tolerance for radiation measurement. The RMSE was smallest in October regardless of slope aspect, and the aspect dependent variation of RMSE was greatest in November. Annual variation in RMSE was greatest on north and south facing slopes, followed by southwest, southeast, and northwest slopes in decreasing order. Once the coefficients are prepared, global solar radiation data from nearby stations can be easily converted to the solar irradiance map at landscape scales with the operational reliability in cropping season.

A Study on Relationships Between Environment, Organizational Structure, and Organizational Effectiveness of Public Health Centers in Korea (보건소의 환경, 조직구조와 조직유효성과의 관계)

  • Yun, Soon-Nyoung
    • Research in Community and Public Health Nursing
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    • v.6 no.1
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    • pp.5-33
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    • 1995
  • The objective of the study are two-fold: one is to explore the relationship between environment, organizational structure, and organizational effectiveness of public health centers in Korea, and the other is to examine the validity of contingency theory for improving the organizational structure of public health care agencies, with special emphasis on public health nursing administration. Accordingly, the conceptual model of the study consisted of three different concepts: environment, organizational structure, and organizational effectiveness, which were built up from the contingency theory. Data were collected during the period from 1st of May through 30th of June, 1990. From the total of 249 health centers in the country, one hundred and five centers were sampled non proportionally, according to the geopolitical distribution. Out of 105, 73 health centers responded to mailed questionnaire. The health centers were the unit of the study, and a various statistical analysis techniques were used: Reliability analysis(Cronbach's Alpha) for 4 measurement tools; Shapiro-Wilk statistic for normality test of measured scores of 6 variables: ANOVA, Pearson Correlaion analysis, regressional analysis, and canonical correlation analysis for the test of the relationships and differences between the variables. The results were. as follows : 1. No significant differences between forma lization, decision-making authority and environmental complexity were found(F=1.383, P=.24 ; F=.801, P=.37). 2. Negative relationships between formalization and decision-making authority for both urban and rural health centers were found(r=-.470, P=.002 ; r=-.348, P=.46). 3. No significant relationship between formalization and job satisfaction for both urban and rural health centers were found (r=-.242, P=.132, r=-.060, P=.739). 4. Significant positive relationship between decision - making authority and job satisfaction were found in urban health centers (r=.504, P=.0009), but no such relationship was observed in rural health centers. Regression coefficient between them was statistically significant($\beta=1.535$, P=.0002), and accuracy of regression line was accepted (W=.975, P= .420). 5. No significant relationships among formalization and family planning services, maternal health services, and tuberculosis control services for both urban and rural health centers were found. 6. Among decision-making authority and family planning services, maternal health services, and tuberculosis control services, significant positive relationship was found between de cision-making authority and family planning services(r=.286, P=.73). 7. A significant difference was found in maternal health services by the type of health centers (F=5.13, P=.026) but no difference was found in tuberculosis control services by the type of health centers, formalization, and decision-making authority. 8. A significant positive relationships were found between family planning services and maternal health services and tuberculosis control services, and between maternal health services and tuberculosis control services (r=-.499, P=.001 ; r=.457, P=.004 ; r=.495, P=.002) in case of urban health centers. In case of rural health centers, relationships between family planning services and tuberculosis control services, and between maternal health services and tuberculosis control services were statistically significant (r=.534, P=.002 ; r=.389, P=.027). No significant relationship was found between family planning and maternal health services. 9. A significant positive canonical correlation was found between the group of independent variables consisted of formalization and de cision-making authority and the group of dependent variables consisted of family planning services, maternal health services and tuberculosis control services(Rc=.455, P=.02). In case of urban health centers, no significant canonical correlation was found between them, but significant canoncial correlation was found in rural health centers(Rc=.578, P=.069), 10. Relationships between job satisfaction and health care productivity was not found significant. Through these results, the assumed relationship between environment and organizational structure was not supported in health centers. Therefore, the relationship between the organizational effectiveness and the congruence between environment and organizational structure that contingency theory proposes to exist was not able to be tested. However decision-making authority was found as an important variable of organizational structure affecting family planning services and job satisfaction in urban health centers. Thus it was suggested that decentralized decision making among health professionals would be a valuable strategy for improvement of organizational effectiveness in public health centers. It is also recommended that further studies to test contingency theory would use variability and uncertainty to define environment of public health centers instead of complexity.

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Proficiency Testing for the Gas-chromatographic Analysis of Procymidone, Chlorpyrifos and Metolachlor Residues in Soil (가스크로마토그래피를 이용한 토양 중 프로사이미돈과 클로르피리포스, 메톨라클로르의 잔류분석 숙련도시험)

  • Kim, Chan-Sub;Son, Kyeong-Ae;Gil, Geun-Hwan;Kim, Jin-Bae;Hong, Su-Myeong;Kwon, Hye-Young
    • The Korean Journal of Pesticide Science
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    • v.17 no.2
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    • pp.94-106
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    • 2013
  • The proficiency testing for the residue laboratories of pesticide registration was conducted in order to improve the reliability and the ability for pesticide residue analysis. On October 2011 the testing was carried out using the soil collected and kept as the moistened state for five years, which is expected to very low residue levels of pesticides. The soil was fortified with chlorpyrifos, metolachlor and procymidone in a manner similar to prepare soil sample for indoor soil degradation test, and then sub-samples were prepared for the distribution to participants. Some of them were randomly selected for confirm of homogeneity and to ensure the stability of samples at room temperature. Samples were consisted of two soil treated as different levels, one of which was used to the assesment and another used to confirm. In addition, provide three standard solutions, respectively concentration of 10 mg/L, and untreated soil. Forty seven institutions submitted results. The medians of results were used as the assigned values for pesticide residues. Fitness for purpose standard deviation of proficiency test was calculated by applying 20% RSD as the coefficient of variation allowed in the soil residue test. Z-score was applied for evaluation of individual pesticides, and the average of the absolute value of the Z-score for the overall assessment of pesticides. Laboratories evaluated the absolute value of the Z-score less than 2 to fit the case of chlorpyrifos and procymidone were 44, metolachlor 40.

A Study of Industrial Workers' Knowledge, Attitude, and Practice of Health Care Services in Busan City (산업장 근로자의 산업보건관리에 대한 지식 태도 및 실천에 관한 조사 연구 -부산지역을 중심으로-)

  • Huang, Bo-Sun;Shin, Yu-Sun;Yun, Suk-Ok;Lee, Ji-Hyun;Kim, Jung-Soon;Kim, Lee-Soon;Kim, Bok-Yong;Kang, Young-Mee
    • Research in Community and Public Health Nursing
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    • v.4 no.2
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    • pp.100-108
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    • 1993
  • The purpose of this study was to identify the workers the Knowledge, Attitude, and Practice of industrial health care services. The study was conducted from Dec 10, 1992 to Jan 20, 1993. The data was collected from 849 workers in 56 companies in Busan City. The data was analyzed by using the mean, S.D>, T-test, ANOVA. The tool for measuring the degree of Knowledge, Attitude and Practice of industrial health care of workers was developed by community health nursing academy and the reliability an of the tool was 0.82810. The results were as follows : 1. The general characteristics of workers : Distribution of workers consisted of laborer(55.0%), office workers(45.0%), in an age range from 25-39(55.0%), male employees were(69.7%), married employees were(62.4%), the educational level with the highest percentage was high school graduates(54.2%). The present work force had a career for 7 years or more with an income of 300-700 thousand won monthly(43.2). 2. The degree of Knowledge Attitude and Practice about industrial health care services of workers : The total score of the Knowledge, Attitude, and Practice was 49.09 points out of a possible 80(mean Score=2.46) 1) The total score of the Knowledge was 15.73 points out of 24. (Mean score=2.62) The following are the Knowledge scores: The necessity examination of occupational disease was(3.34) The knowledge of occupational disease was (3.12) The knowledge of health education was(1.29) 2) b. The total score of the Attitude was 26.01 point out of 44(mean score=2.36) The following are the Attitude scores: The necessity of health education for health examination was (3.14). The importance of health examination was(3.08) The necessity of measurement for working environment was(2.99). The satisfaction of the content in the periodic health examination was low(1.81). 3) The total score of the Practice was 7.35 points out of 12(mean score=2.45) The following are the orders of Practice scores: The participation in health examination was higher than in health education(1.33). 3. The general characteristics and the degree of knowledge, Attitude, and Practice of workers of industrial health care. 1) The level of worker's knowledge was significantly related by working part(t=2.54 P=0.000), marital status(F=4.35 P=0.029), educational level(F=3.91 and P=0.020), monthly income(F=2.98 P=0.029) 2) There were no significant difference between the general characteristics and the attitude of workers. 3) The practice was significantly related with working part(T=2.52 P=0.012), sex(T=2.28 P=0.23), marital status(F=4.25 P=0.012), monthly income (F=2.76 P=0.034) 4) The total score had a significant difference with working part(T=2.39 P=0.017), sex (T=3.84 P=0.000), marital status (F=3.18 P=0.032). Educational level (F=3.20 P=0.033), and monthly income(F=3.05 P=0.022).

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The consideration for methods of statistical analysis about the thesis published in the journal of korean oriental medical Ophthalmology & Otolaryngology & Dermatology from 2003 to 2005 (2003년부터 2005년까지 안이비인후피부과 학회지에 게재된 논문들의 통계적 분석 방법에 대한 고찰)

  • Kim, Keoo-Seok;Nam, Hae-Jung;Park, Owe-Suk;Kim, Hee-Jeong;Cha, Jae-Hoon;Kim, Yoon-Bum
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.19 no.3 s.31
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    • pp.134-145
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    • 2006
  • Objective : This study was carried out to investigate what type of assumption and conditions are needed for the application of various statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test and to evaluate that they are used correctly in the research process. Methods : One more methods of statistical analysis were used in 91 papers among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatology from April 2003 to December 2005. So we analysed the type of statistical analysis method in 91 papers(clinical and experimental study) and assessed the their validity of statistical techniques by the check list consisting of 34 items(3 items for validity assessment of descriptive statistics, 6 items for t-test, 7 items for analysis of variance, correlation analysis and regression analysis, respectively, 4 items for chi-square test) Results : 1. The type of 65(40%) cases is experimental trial, the type of 55(34%) cases is case report, the type of 26(16%) cases is clinical trial and the type of 16(10%) cases is review, in 91 papers using statistical techniques among 162 papers selected from the journal of Korean oriental medical Ophthalmology & Otolaryngology & Dermatol-ogy from April 2003 to December 2005. 2. One more methods of statistical analysis were used in the experimental and clinical study. When we classified 125 units using statistical analysis methods in 91 papers according to statistical techniques such as descriptive statistics, t-test, analysis of variance, correlation analysis, regression analysis and chi-square test, the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of independent sample t-test is 33(26%), the number of only descriptive statistics is 28(22%), the number of one way ANOVA is 15(12%), the number of non-parametric test 10(8%). 3. After carrying out one way ANOVA, the number of using multiple comparison methods is 15(Scheffe:6(26%), Duncan:4(17%), Dunnett:3(13%), Tukey:2(9%)) out of 23 (total case carrying out one way ANOVA). 8(35%) out of 23 did not enforce multiple comparison methods after carrying out one way ANOVA. 4. From the assessment of validity about 63 cases using statistical techniques(except descriptive statistics), 5(8%) cases are proper, the other 58(92%) are improper, so we recognized a serious misuse of statistical application in our journal. 5. The number of case below 10 sample size in experimental and clinical study(except descriptive statistics) is 31(34%) and frequent. Also the number of case containing no mention of sample size is 41(45%, including culture study). 6. For example of statistical error, there are wrong choice of statistical technique, lack of check on standard assumption(such as standard distribution, equivariance, independence), and so on. Conclusions : We investigated the validity of statistical analysis methods in our journal by check list consisting of 34 items and suggested correct statistical analysis methods. We should practice the spread of education about statistical analysis methods and precis application, enhance objectivity and reliability of our thesis and further correspond with purpose of scientific study.

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Evaluation of Hydrogeologic Seal Capacity of Mudstone in the Yeongil Group, Pohang Basin, Korea: Focusing on Mercury Intrusion Capillary Pressure Analysis (포항분지 영일층군 이암층의 수리지질학적 차폐능 평가: 수은 모세관 압입 시험의 결과 분석을 중심으로)

  • Kim, Seon-Ok;Wang, Sookyun;Lee, Minhee
    • Economic and Environmental Geology
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    • v.53 no.1
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    • pp.23-32
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    • 2020
  • Geological CO2 sequestration is a global warming response technology to limit atmospheric emissions by injecting CO2 captured on a large scale into deep geological formations. The presented results concern mineralogical and hydrogeological investigations (FE-SEM, XRD, XRF, and MICP) of mudstone samples from drilling cores of the Pohang basin, which is the research area for the first demonstration-scale CO2 storage project in Korea. They aim to identify the mineral properties of the mudstone constituting the caprock and to quantitatively evaluate the hydrogeologic sealing capacity that directly affects the stability and reliability of geological CO2 storage. Mineralogical analysis showed that the mudstone samples are mainly composed of quartz, K-feldspar, plagioclase and a small amount of pyrite, calcite, clay minerals, etc. Mercury intrusion capillary pressure analysis also showed that the samples generally had uniform particle configurations and pore distribution and there was no distinct correlation between the estimated porosity and air permeability. The allowable CO2 column heights based on the estimated pore-entry pressures and breakthrough pressures were found to be significantly higher than the thickness of the targeting CO2 injection layer. These results showed that the mudstone layers in the Yeongil group, Pohang basin, Korea have sufficient sealing capacity to suppress the leakage of CO2 injected during the demonstration-scale CO2 storage project. It should be noticed, however, that the applicability of results and analyses in this study is limited by the lack of available samples. For rigorous assessment of the sealing efficiency for geological CO2 storage operations, significant efforts on collection and multi-aspect evaluation for core samples over entire caprock formations should be accompanied.

A Study on the Antigastritic Effects of Rheum Species Extracts and Their Active Components (대황 추출물의 항위염 작용과 유효성분에 관한 연구)

  • Hwang, In Young;Jeong, Choon Sik
    • Journal of Food Hygiene and Safety
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    • v.28 no.4
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    • pp.330-336
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    • 2013
  • Rheum tanguticum has long been used in oriental medicine as antipyretics, analgesics, anti-inflammation, aperient, hypertension medicine and medicine for skin disease. This study has investigated the effectiveness of defense for gastritis making use of Rheum tanguticum and its similar plants, Rumex cripus, Rheum officinale, Rhem palmatum and Rheum undulatum. Chysophanol, chrysophanol-8-O-glc, Desoxyrhaponticin desoxyrhaponti-genin, emodin, isorhaponticin, 2-methoxy-4-hydroxyanthraquinone-5-O-glc, physcion, pirace-tannol-3'-O-glc, resveratrol, rhaponticin and rhapontigenin are used as the components of Rheum tanguticum. In HCl ethanol-induced gastritis in rat, the most effective extract was 70 percent ethanol which is of Rheum tanguticum, showing the inhibition of 91.8 percent to the gastric lesions. 70% ethanol extract of Rhem palmatum and Rumex cripus shown inhibition of 75.6 percent and 73.2 percent, respectively. This effectiveness is considered as acid-neutralizing capacity, anti-H.pylori and anti-oxidant activity. 70% ethanol extract of Rheum tanguticum and its component, piracetannol-3'-O-glc exhibited higher free radical scavenging activity than others. These results suggest that Rheum species extracts and their active components could be utilized for the treatment of gastritis. Furthermore, these results are expected to contribute the standardization with objectivity and reliability for Rheum species, medicinal herbs. In addition, it can contribute to the prevention of indiscriminate distribution of imitation, and the rising rate of dependence on imports of medicinal herbs, and mixing prevention of low-quality goods.