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Improvement of Total Chrolophill Analytical Methods for the Chlorella Products with Extended Products Types (신 제형 클로렐라제품의 총 엽록소 시혐법 개선)

  • Kim, Yoo-Kyung;Lee, Eun-Suk;Han, Jae-Gab;No, Gi-Me;Lim, Dong-Gil;Jung, Ja-Young;Park, Young-Sig
    • Journal of Food Hygiene and Safety
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    • v.26 no.1
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    • pp.70-75
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    • 2011
  • A new and improved analytical method involving alkaline pyridine extraction was proposed to quantity chlorophyll contents in syrup and candy type chlorella products. The performance of analytical method was compared with the conventional Korea food standard method which involves acetone extraction. The application of sonication chlorophyll extraction form alkaline pyridine sample was also explored. The analytical procedure was validated by evaluating accuracy, precision and reproducibility. For liquid samples, the pyridine extraction method showed higher accuracy and precision compared to acetone extraction method. The CV values of pyridine extract method and the acetone extraction method were 18.82 and 40.0, and the accuracy to theoretical values were 106.3% and 78.1%, respectively. When sonication extraction method was applied to the pyridine extraction, the precision was improved as indicated by reduced CV values from 18.82 to 11.36. The improved performance of pyridine-sonication extraction was also validated by recovery test of chlorophyll that was previously spiked into the sample matrix. For solid matrix, the pyridine extraction method showed better performance in analysis of chlorophyll in solid food matrix (CV = 7.05) compared to conventional acetone extraction method (CV = 30.0). However, the accuracy to theoretical values of pyridine and acetone extraction methods only showed only 62.7% an 40%, respectively. The relatively low accuracy of pyridine extraction method (62.7%) was improved to 99.4% by applying additional sonication extraction method. The improved performance of applying additional sonication extraction was validated by standard deviation, CV values and accuracy to theoretical values.

Screening Test for Heart Diseases in the First Grade Elementary School Children in Busan (부산 지역 초등학교 1학년 학생들의 심장질환의 집단검진에 관한 연구)

  • Oh, Jae Min;Park, Hee Ju
    • Clinical and Experimental Pediatrics
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    • v.46 no.5
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    • pp.490-494
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    • 2003
  • Purpose : We'd like to determine the incidence of congenital heart disease and arrhythmia in elementary school children in Busan, and to provide adequate prevention and treatment. Methods : A total of 23,802(male 12,909, female 10,893) 1st grade elementary school children living in Busan were studied. All children were 7-8 years old. We obtained their medical history by questionnaire and checked elecrocardiography(ECG). Subsequent screening tests including a 2nd ECG, chest X-ray, phonocardiogram and CBC for the students who had abnormal findings at the first screening test. The third screening test was done for students who had cardiac murmurs or abnormal ECG findings in the second screening test by echocardiogram, treadmill test and 24-hour Holter monitoring. Results : Among 23,802 children participants, 605(2.54%) had abnormal ECG findings at the first screening test. Q wave abnormality(0.58%) was observed most frequently, and complete right bundle branch block(RBBB)(0.26%), sinus tachycardia(0.24%), right axis deviation(0.22%) and ventricular premature contraction(VPC)(0.21%) followed in order. Four hundred and twenty four children participated in the second ECG screening test. Two hundred and two children(47.6%) had an abnormality such as sinus tachycardia(18.8%), VPC(17.8%), or complete RBBB(17.3%). After completing the third examination including echocardiogram, we couldn't find the students with ventricular tachycardia (VT) or SVT at the third arrhythmia screening test. Conclusion : A high incidence of arrhythmia was found in the 1st grade elementary school children in Busan despite their healthy appearances, although fatal heart diseases were not noted. Early diagnosis, adequate preventative measures and treatment will prevent and decrease the frequency of emergent situations like syncope and sudden death.

Relationship between cord blood level of IL-12 in preterm newborns and development of wheezing (34주 미만 미숙아 제대혈청 내 interleukin-12 농도와 영아기 천명 발생과의 관계)

  • Yu, Hyo Jung;Park, Eun Ae;Kim, Ji Young;Cho, Soo Jin;Kim, Young Ju;Park, Hye Sook;Ha, Eun Hee
    • Clinical and Experimental Pediatrics
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    • v.51 no.7
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    • pp.754-759
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    • 2008
  • Purpose : Abnormal activation patterns of Th1/Th2-cells have been suggested to increase the prevalence of allergic diseases. Prevention is regarded as an important corner stone in the management of allergic diseases. In this study, we have investigated the relationship between cord blood levels of IL-4, IL-10, and IL-12 in preterm newborns and the development of allergic respiratory diseases in infancy Methods : Forty-six preterm newborns born at the Ewha Womans University Mokdong Hospital between January 2003 and July 2005, were enrolled for this study, and consent was obtained to test their cord blood samples. Clinical history was obtained from the hospital records. Cord blood was obtained at birth and kept frozen until it was tested. The levels of IL-4, IL-10, and IL-12 were determined by enzyme-linked immunosorbent assay (ELISA). Results : All infants were followed-up for a median of $16.0months{\pm}13.2d$ (range, 12.0 to 36.0 months). Eighteen infants who developed wheezing showed lower cord blood levels of IL-12 ($366.60{\pm}140.40$ vs $435.09{\pm}91.20pg/mL$, P=0.009). Cord blood levels of IL-4 and IL-10 showed no significant difference between the two groups. Four newborns who later developed asthma, and infants with asthma showed lower IL-12 level in the cord blood than other groups. Conclusion : Lower concentration of cord blood levels of IL-12 in newborns who later developed wheezing and asthma suggested that they had abnormal activation patterns of Th1/Th2-cells at the time of birth, and cord blood IL-12 level can be used as a predictor of allergic respiratory diseases.

Effect of Different Fertilization on Physiological Characteristics and Growth Performances of Eucalyptus pellita and Acacia mangium in a Container Nursery System (시비처리가 Eucalyptus pellita와 Acacia mangium 용기묘의 생리 및 생장 특성에 미치는 영향)

  • Cho, Min-Seok;Lee, Soo-Won;Bae, Jong-Hyang;Park, Gwan-Soo
    • Journal of Bio-Environment Control
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    • v.20 no.2
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    • pp.123-133
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    • 2011
  • The objective of this study was to find optimal nutrient condition of container seedling production of two tropical species for high seedling quality. This study was conducted to investigate photosynthesis, chlorophyll fluorescence, chlorophyll contents, and growth performances of container seedlings of Eucalyptus pellita and Acacia mangium growing under four different fertilization treatments (Con., $0.5\;g{\cdot}l^{-1}$, $1.0\;g{\cdot}l^{-1}$, and $2.0\;g{\cdot}l^{-1}$ fertilization). E. pellita showed outstanding photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $1.0\;g{\cdot}l^{-1}$ fertilization. Meanwhile, E. pellita showed the highest photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $2.0\;g{\cdot}l^{-1}$ fertilization, as fertilization rate were increased, those of A. mangium increased. Like physiological characteristics, Both E. pellita at $1.0\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization were higher root collar diameter, height, biomass, and seedling quality index than other treatments. These results showed that E. pellita at $1\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization is optimal nutrient condition, respectively. Moreover, fertilization rate controlling is very important for growth and seedling quality of container seedling.

Fortschritte in der Diagnostik von $Eisenstoffwechselst\ddot{o}rungen$ (철대사장애(鐵代謝障碍)의 진단(診斷)에 관(關)한 최근동향(最近勳向))

  • Keiderling, Walter
    • The Korean Journal of Nuclear Medicine
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    • v.4 no.1
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    • pp.1-9
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    • 1970
  • 철대사(鐵代謝)에 관(關)한 연구(硏究)는 과거(過去) 30년(年)동안 새로운 검사방법(檢査方法)의 도입(導入)으로 눈부신 발전(發展)을이룩하였다. 1937년(年) Heilmeyer 등(等)에 의(依)하여 Ortho-phenanthrolin방법(方法)의 개발(開發)로 저색소성빈혈(低色素性貧血)의 원인(原因)이 구명(究明)되고 또한 이에 대(對)한 치료(治療)의 원칙(原則)이 세워졌다. 그 후 심(甚)한 감염(感染)이나 악성종양(惡性腫瘍)을 가진 환자(患者)者에서 관찰(觀察)되는 빈혈(貧血)에 대(對)해서 하나의 가설(假說)을 세워 이를 설명(說明)하려 하였는데 이는 곧 혈장(血漿)으로부터 철분(鐵分)이 신속(迅速)히 소실(消失)되어 망내계(網內系)나 병변(病變)이 있는 국소부위(局所部位)에 주(主)로 모여 들어 특수(特殊)한 방어기능(防禦機能)을 발휘(發揮)한다는것으로 연자(演者)는 방사성동위원소(放射性同位元素)를 이용(利用)하여 이 가설(假說)을 증명(證明)하였으며 이 연구(硏究)에는 또한 이문호교수(李文鎬敎授)가 Freiburg대학(大學) 유학중(留學中) 참여(參與)한 바 있다. 철대사(鐵代謝)를 파악(把握)하기 위(爲)해서 $^{59}Fe$가 흔히 사용(使用)되는데 이러한 방사성동위원소(放射性同位元素)를 이용(利用)함으로서 다음 사항(事項)들을 관찰(觀察)할 수 있었다. 즉(卽) 1. 소화장기(消化臟器)로 부터의 철흡수(鐵吸收) 2. 혈장(血漿)에서의 철(鐵)의 소실속도(消失速度) 3. 혈장내(血漿內)에서의 철교체율(鐵交替率) 4. 적혈구(赤血球)의 철이용(鐵利用) 5. 생체내(生體內)의 철분포(鐵分布) 6. 철배설(鐵排泄)의 정량적(定量的) 분석(分析) 또한 근년(近年)에는 특수(特殊)한 기능(機能)을 발휘(發揮)할 수 있는 동위원소(同位元素)를 이용(利用)하여 철흡수(鐵吸收) 및 대사이외(代謝以外)에도 적혈구(赤血球)의 수명(壽命)과 혈액량등(血液量等)을 측정(測定)하게 되었다. 경구적(經口的)으로 투여(投與)된 철(鐵)은 대부분(大部分) 십이지장(十二指腸)의 상부(上部)에서 흡수(吸收)되고 무기철(無機鐵)이 보다 쉽게 흡수(吸收)되어 가(價)의 상태(狀態)로 된다. 혈장(血漿)에서는 transferrin에 의(依)해서 철(鐵)이 운반(運搬)된다. 혈장철(血漿鐵)의 대부분(大部分)은 혈색소분해(血色素分解)에서 유래(由來)되며 이는 다시 혈색소(血色素)의 재생(再生)에 이용(利用)되는데 혈장내(血漿內) 철교체율(鐵交替率)은 방사성철(放射性鐵)을 이용(利用)하여 측정(測定)할수 있다 이와같이 방사성철(放射性鐵)을 이용(利用)하여 철대사과정(鐵代謝過程)을 숙지(熟知)함으르서 임상(臨床)에 응용(應用)하기에 이르렀으며 다음과 같은 질환(疾患)의 진단(診斷)에 특(特)히 큰 도움을 준다. A. 진성철결핍증(眞性鐵缺乏症) : 혁색소철(血色素鐵) 및 저장철(貯藏鐵)을 포함(包含)한 생체내(生體內) 전철분(全鐵分)의 부족(不足)된 상태(狀態)로서 실혈(朱血)에 의(依)한 것이 대부분(大部分)이다. 이 경우 철흡수(鐵吸收)는 증가(增加), 혈장철치(血漿鐵値)는 저하(低下), 철소실속도(鐵消失速度)는 증가(增加)되며 혈장철(血漿鐵) 교체율(交替率)은 항진(亢進) 혹(或)은 정상(正常)이다. B. 심(甚)한 염증성(炎症性) 질환(疾患) : 이 경우에도 혈장철치(血漿鐵値)의 저하(低下), 소실속도(消失速度)의 증가(增加), 교체율(交替率)은 정상(正常)보다 4배(倍)까지 증가(增加)할 수 있다. 골수(骨髓)에서 보다는 간(肝), 비(脾)와 같은 망내계(網內系)에 방사성철(放射性鐵)이 집결(集結)되는 것으로 보아 혈색소철(血色素鐵)보다는 저장철(貯藏鐵)이 관여(關與)되는 것이다. C. 원발성(原發性) 혈색소증(血色素症)(Idiopathic hemochromatosis) : 혈장철(血漿鐵)의 증가(增加)가 현저(顯著)하며 transferrin 농도(濃度)는 정상(正常)보다 낮으나 거의 대부분(大部分)의 철분(鐵分)으로 포화(飽和)된다. 철흡수(鐵吸收)는 증가(增加)되고 철소실속도(鐵消失速度)는 감소(減少) 되어 있으나 교체율(交替率)은 항진(亢進)되어 있다. 혈장철(血漿鐵)은 간(肝), 비(脾) 등(等)의 기관(器管)으로 저장집결(貯藏集結)되어 철저류(鐵貯溜)가 증대(增大)되므로 철이용증((鐵利用症)은 저하(低下)된다. D. 선천성(先天性) 무(無)$\ulcorner$트란스헤 린$\lrcorner$증(症)(Congenital atransferrinemia) : 방사성철(放射性鐵)을 이용(利用)한 진단방법(診斷方法)으로 Freiburg에서 7세(歲)의 소녀(少女)에서 발견(發見)한 증례(症例)인데 간(肝), 비(脾), 심(心)의 비대(肥大)가 임상적(臨床的)으로 인지(認知)되었고 중증(重症)의 철결핍상(鐵缺乏狀)을 검출(檢出)할 수 있었다. 철흡수율(鐵吸收率)의 상승(上昇), 혈장철치(血裝鐵値)의 감소(減少), 혈장철소실속도(血漿鐵消失速度)의 증가(增加), 혈장철교체율(血漿鐵交替率)의 상승(上昇) 및 적혈구(赤血球)에서의 철분이용율(鐵分利用率)의 저하(低下)를 ferrokinetic study에서 알 수 있었고 간(肝)에서 고도(高度)의 방사능(放射能)이 검출(檢出)되는 반면(反面), 비(脾)에서는 극소(極小), 골수(骨髓)에는 전(全)혀 방사능(放射能)이 들어가 있지 않았다. 이 증례(症例)와 같이 transferrin이 없으면 철분(鐵分)은 쉽게 조직(組織)으로 들어가 hemosiderin으로 저장(貯藏)되고 골수(骨髓)는 고도(高度)의 철결핍증(鐵缺乏症)을 나타내어 기관철침착증(器管鐵沈着症)과 철결핍성빈혈(鐵缺乏性貧血)이 동시(同時)에 나타나게 된다. 철대사장애면(鐵代謝障碍面)으로 보아 많은 미해결점(未解決點)이 남아 있으며 앞으로 자라나는 젊은 학도(學徒)들이 구명(究明)할 문제(間題)라고 믿는다.

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Quantification of Myocardial Blood flow using Dynamic N-13 Ammonia PET and factor Analysis (N-13 암모니아 PET 동적영상과 인자분석을 이용한 심근 혈류량 정량화)

  • Choi, Yong;Kim, Joon-Young;Im, Ki-Chun;Kim, Jong-Ho;Woo, Sang-Keun;Lee, Kyung-Han;Kim, Sang-Eun;Choe, Yearn-Seong;Kim, Byung-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.3
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    • pp.316-326
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    • 1999
  • Purpose: We evaluated the feasibility of extracting pure left ventricular blood pool and myocardial time-activity curves (TACs) and of generating factor images from human dynamic N-13 ammonia PET using factor analysis. The myocardial blood flow (MBF) estimates obtained with factor analysis were compared with those obtained with the user drawn region-of-interest (ROI) method. Materials and Methods: Stress and rest N-13 ammonia cardiac PET imaging was acquired for 23 min in 5 patients with coronary artery disease using GE Advance tomograph. Factor analysis generated physiological TACs and factor images using the normalized TACs from each dixel. Four steps were involved in this algorithm: (a) data preprocessing; (b) principal component analysis; (c) oblique rotation with positivity constraints; (d) factor image computation. Area under curves and MBF estimated using the two compartment N-13 ammonia model were used to validate the accuracy of the factor analysis generated physiological TACs. The MBF estimated by factor analysis was compared to the values estimated by using the ROI method. Results: MBF values obtained by factor analysis were linearly correlated with MBF obtained by the ROI method (slope = 0.84, r = 0.91), Left ventricular blood pool TACs obtained by the two methods agreed well (Area under curve ratio: 1.02 ($0{\sim}1min$), 0.98 ($0{\sim}2min$), 0.86 ($1{\sim}2min$)). Conclusion: The results of this study demonstrates that MBF can be measured accurately and noninvasively with dynamic N-13 ammonia PET imaging and factor analysis. This method is simple and accurate, and can measure MBF without blood sampling, ROI definition or spillover correction.

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A Study on the Establishment of Management Methods about Occupational Dermatoses (직업성 피부질환에 대한 현황 파악 및 관리 대책 수립을 위한 연구)

  • Lim, Hyun-Sul;Cheong, Hae-Kwan;Choi, Byung-Soon;Kim, Ji-Yong;Sung, Yeol-Oh;Kim, Yang-Ho
    • Journal of Preventive Medicine and Public Health
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    • v.29 no.3 s.54
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    • pp.617-637
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    • 1996
  • Occupational dermatosis is one of the most prevalent occupational disorders. However, the extent of the occupational dermatoses including incidences and prevalencies of each disease entity, and etiologic materials are not yet welt stated in Korea. Authors reviewed the literatures on the statistic data and reports on the occupational dermatoses, and surveyed on the occupational dermatoses in two factories, and surveyed the physicians responsible to the occupational dermatoses with formed questionnaire. The results are as follows; 1. Among medical journals published since 1964, there were 31 articles on the occupational dermatoses. Of 31 articles, 18 were case reports and all others were review articles. Of 18 case reports, 9 were epidemiologic survey. The Workers' Periodic Health Examinations revealed that prevalence of the occupational dermatoses was highest(4.36 per 10,000 workers) in 1974, but number of the cases reported were decreased sharply since 1978 with some tendency to increase since 1981. There were 2,240 reported cases of occupational dermatoses between 1966 and 1992, which is 1.90% of all the reported occupational diseases. Skin infection and injuries due to chemicals were most frequent and there were 6 cases of skin cancer. 2. In an epidemiological survey on the dermatoses among 995 workers in a metal product manufacturing factory and 225 workers in a coal chemical factory, there were 794 with dermatomycosis, 296 workers with acne, 130 workers with scar, 123 workers with deformity of toe nails. Scars, photosensitivity dermatitis, deformity of finger and toe nails, and acne were more prevalent in the metal product manufacturing factory(p<0.05). In the metal prouct manufacturing factory, workers treating organic solvents and oils had more dermatoses than those without treating the materials(p<0.05). On the skin patch performed on 16 workers in the metal product manufacturing factory, there were 8 cases of irritation dermatitis and 5 cases of contact dermatitis. Prevalence of contact dermatitis in the metal product manufacturing factory was 1.3%. 3. On the questionnaire survey, 34 dermatologists, 29 doctors of preventive medicine, and 22 family physician replied. The proportion of occupational etiology among all dermatoses assumed by the physicians were below 9%, and the most important occupational dermatosis in Korea was contact dermatitis. Main etiologic materials related to the occupational dermatosis were organic solvent, acid and alkali, and metals. The reason for the scarcity of report of occupational dermatoses were difficulty in diagnosis and physician's ignorance of the occupational etiology. They replied that to prevent the occupational dermatoses in the workplace, the use of protective devices was most important, and development of diagnostic criteria on the occupational dermatoses is urgent. Above results shows us that there is many workers with occupational dermatoses, but they are mostly unreported. Measures to prevent and manage the occupational dermatoses are not satisfactory at present. Hence, authors suggest measures for the precise diagnosis, report and prevention of the occupational dermatoses. a. Dermatologist, preventive physician, and industrial hygienist should work as a team to examine the high risk group and establish the preventive measures. b. Disease entities, diagnostic criteria of occupational dermatoses should be listed, criteria for the compensation and job fitting at recruitment should be established, and manual for the proper treatment and effective prevention of each occupational dermatosis should be developed. c. Patch test antigens against each occupational category should be developed and it should be available to any physicians responsible. d. To facilitate the diagnosis of occupational dermatoses by the doctors responsible for the Workersr Periodic Health Examination, development of standardized questionnaire, education on the techniques of the patch test, and cooperation with the dermatologist in diagnosis of occupational dermatoses is essential.

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Studies on Silk Textile Wash and Wear Finishing (絹織物 Wash and Wear 加工硏究)

  • Choe, Byong-Hee;Lee, Yang-Hoo
    • Journal of Sericultural and Entomological Science
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    • v.23 no.1
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    • pp.47-55
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    • 1981
  • Silk textile finishing has been studied for many years by many workers in order to meet more utilities for various endusers. Such studies, however, could not be successful because any natural fibers are hardly change their natures by artificial treating methods. Textile finishing is of course to improve the mechandise qualities and the poor natures of silk so that it may be available as the best textile fiber in the world. Sometimes, famous trade marked textile plays more power than its quality in the silk market, nevertheless, this should be over line of research activities. Meantime, the silk demand has been also transferred from ladies stocking to other clothes since nylon or other synthetic fibers were developed. That is why, the extension of silk demand should be developed by various research works. Specially, silk is known as difficult textile to handle it during washing or ironing process which happened to depress down the silk usage for house wives. In order to solve such problems, the reporter has been worked for many years and now, he believes that he has developed a proper finishing method to coversuch problems. The developed finishing method may be said to eligible with economical aspect and shorten the dry duration after water washing in half against normal silk textile without harming the specific silk nature. As all of us know, silk fiber starts to denature since it was spinned by silkworm and the fiber is formed as overlapped "S" type curves during its concooning process. After it is made as raw silk or sericin silk, it shows as straight line form, but it changes in to waved form in case refining or degumming process in order return to its original spinned form. Such nature is continued during its textile form and ends with hard ironing nature than other textile fibers. Mean while, the silk fiber keeps to continue its denaturing and this is iniciated by repeat of washing and drying which takes many years to reach its final stage, The reporter has found the iniciating denature of silk by his finishing process, with out heat, decreasing the swollen nature which ended with shortening the drying duration after wash. Each washing was carried out by soaking the previously weighed sample in cold water for one hour, then pressed the sample for ten minutes to eliminate its free water component before weighing with same condition. According to this, the treated silk showed much denaturing after the finishing, but the standard silk progressed the denaturing by and by with the repeat of washing and drying, finally reached the same swollen degree of treated silk, Such treating result explains that the treated silk happened to be stebilized nature by the treating immediately. On the other that the treated silk happened to be stebilized nature by the treating immediately. On the other hand, standard silk may reach to such condition by the time of worn out clothes after repeat of washing and drying for many years while the clothes will be no more useful. The decreased swelling nature has brought about the drying period in half against standard silk after all. Not only the tests of tenacity and elongation but also crease resistance recovery, stiffness and shrinkage tests were carried out after each washing and drying which he has found better result on the treated silk textile against the standard silk. The most important thing was to keep the textile feeling of silk by such finishing work before improve any poor nature of silk. The general silk has a nature to absorb smoke or dirt from its surrounding air and reaches to dirty color shade upon such exposure, but the treated one has improved such nature because of its artificial denaturing, another word, it keeps clean longer than the normal silk. Many previous finishing works could improve some specific nature of silk, but it happened to deprave other important natures. The reporters work is, however, specialized to improve the silk to be useful as Wash and Wear Silk without harming its standard natures. So far, this work happened to be a overall innovative finishing method of silk textile.

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Germinability and Physiological Properties of Maize Seeds Affected by Matriconditioning (Matriconditioning에 의한 옥수수 종자 활력증진과 생리적 특성변화)

  • 이석순;서정문;윤상희;이문정
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.3
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    • pp.267-275
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    • 2003
  • To observe the effects of seed matriconditioning on the emergence, plumule growth, and seed physiological properties of normal and aged seeds of three corn(Zea mays L.) genotypes (dent, sugary, and shrunken-2), normal and artificially aged seeds were matriconditioned at 50, 75, 100, and 125% moisture contents of vermiculite at $25^{\circ}C$ for 24 hours and the germinability was examined at $25^{\circ}C$ and in cold test (7 days at 1$0^{\circ}C$followed by $25^{\circ}C$). Emergence rate, emergence speed, and plumule growth were smaller in the order of dent>sugary>shrunken-2. Matriconditioning did not affect the emergence rate of normal dent and sugary seeds, while it enhanced emergence speed and plumule growth. In contrast, the emergence rate, emergence speed, and plumule growth of normal shrunken-2 and aged seeds of all genotypes were enhanced as the moisture content of vermiculite increased up to 125% both at $25^{\circ}C$ and in cold test. Matriconditioning promoted $\alpha$-amylase activity and DNA and soluble protein contents, while it reduced the leakage of total sugars and electrolytes from the seeds when soaked in water.

Relationship between Light Environment and Crop Growth under Various Nitrogen Application Rates Condition in Rice Plant Canopy (질소(窒素) 시비수준(施肥水準)에 따른 벼 군락내(群落內) 광환경변화(光環境變化)와 생육(生育)과의 관계(關係)에 관(關)한 연구(硏究))

  • Lee, Jeong-Taek;Kazuo, Kobayashi
    • Korean Journal of Environmental Agriculture
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    • v.8 no.2
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    • pp.128-135
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    • 1989
  • To find the effects of solar energy into the rice canopy and its balance on the rice plant growth, a Tongil type rice, Raekyeong and a japonica rice, Koganebare were used with four levels of nitrogen fertilizer application, 6, 10, 14, and 18kg $l0a^{-1}$ in Chigugo, Japan. The micrometerosological data, the solar radiation and absorbed solar radiation by the rice plants, and leaf area index on cardinal growth stage of the rice community were measured. The results are as follows : Raekyeong showed increased LAI by increased nitrogen fertilizer application rates, and larger LAI than Koganebear. 1. There was no difference in total dry weight till 20 days after transplanting regardless of nitrogen levels in the same variety, after that, however, Raekyeong showed higher dry matter productions for the same durations than Koganebare. 2. In early growth stage of transplanting rice, reflection ratio of solar radiation above the crop canogy was about 6%, however, it was increased up to 20% by the increased LAI at heading date. 3. In high levels of nitrogen application plots, LAI were increased so that values were decreased. 4. Relationship between the amount of absorbed radiation by plants and its dry matter production was linearly significant. Higher levels of nitrogen application produced higher dry matter in Raekyeong, however, in lower level, the dry matter production pattern was almost similar between both rice cultivars.

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