• Title/Summary/Keyword: material interaction

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The Permeability of Capsule Type Fertilizer and Herbicide with Chitoasn and Alginic Acid (Chitosan과 Alginic Acid를 이용한 캡슐형 비료 및 제초제의 투과특성)

  • LEE Keun-Tai;KIM Sang-Moo;PARK Seong-Min;SON Byung-Yil;KIM Hyoung Seub;LEE Sang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.2
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    • pp.313-318
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    • 1997
  • Effects of the concentration of NaCl, the concentration and the molecular weight of chitosan on the permeability of capsule type fertilizer and herbicide were investigated. The encapsulating process was based on the electrostatic interaction between chitosan (a polycationic polymer) and sodium alginate (an anionic polysaccharide). Sodium alginate solution $(1\%)$ was dropped into chitosan solution $(1\%)$ in which various amounts of NaCl was added. The capsule strength was increased with the addition of NaCl and the maximum value of capsule strength was observed at 0.3M NaCl. Capsule type fertilizer and herbicide were immersed in deionized water to determine its permeability, and it was affected by the concentration of NaCl and chitosan, and the molecular weight of chitosan. As the concentration of NaCl in chitosan solution increased, permeability of the capsule increased and marked the maximum value of $ 88\%$(fertilizer), $87\%$ (herbicide) at 0.75M NaCl. As concentration of chitosan solution increased, permeability tended to decreased; it showed the maximum value of $90\%$ (fertilizer) and $90.3\%$ (herbicide) at $0.25\%$ chitosan and the minimum value of $83\%$ (fertilizer) and $82\%$ (herbicide) at $1\%$ chitosan. Permeability of fertilizer and herbicide also decreased, as the molecular weight of chitosan (material of capsule) was decreased; it was showed $86\%$ (fertilizer) and $83\%$ (herbicide) at M.W 330,000 (sonication time 0min) and $52\%$ (fertilizer) and $51\%$ (herbicide) at M.W 119,000 (sonication time 180 min). The chitosan-alginic acid capsule was manufactured (defined as prepared capsule), dried for 6 hrs and immersed in deionized water (defined as restored capsule) to examine restoration of capsule. Restoration of capsule was good, and capsule strength was slightly decreased form $20g/cm^2$ (prepared capsule) to $17g/cm^2$ (restored capsule)

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A Theory Construction on the Care Experience for Spouses of Patients with Chronic Illness (만성질환자 배우자의 돌봄 경험에 대한 이론 구축)

  • Choi, Kyung-Sook;Eun, Young
    • Journal of Korean Academy of Nursing
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    • v.30 no.1
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    • pp.122-136
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    • 2000
  • Chronic illness requiring attention and management during a long period of time puts great burden onto patients, their family and society. For patients with chronic illnesses, providing social support is the most important, and the fundamental support comes from their spouses. Amount and quality of support from spouses seems to differentiated according to the sex of patients. Female patients tend to believe that their spouses are not very supportive. Therefore, the researchers assessed the burden of husbands of female arthritis patients to discover the factors that result in greater burden. Also, they developed a theoretical model of husbands′ care for their wives through a qualitative research into husbands′ experience. Method 1: The study material was 650 female arthritis patients registered in an arthritis clinic. The questionnaire about the disease experience of female arthritis patients and the burden of husbands were sent. Returned questionnaires numbered 210(32.3%) and 27 were excluded because of inadequate answers. The remaining 183 questionnaires were analyzed. The mean age of the patients was 51 years and the mean age of spouses was 55 years. The mean marital period was 28 years. The average duration since diagnosis was 9.1 years. Education level was varied from primary school to graduate school, and average income/month was 1,517,300 won. Method 2: Initial questionnaire studies on the burden of husbands were performed. Among 183 responding husbands, 23 consented to participate for a qualitative research. Data was obtained by direct and telephone interviews. The mean age of participants was 58 years, and the educational level and socioeconomic status also varied. Result: 1. Husbands′ burden: The average burden was 57.68 with a range of 6-96. 2. Burden and general characteristics: The husband′s burden correlated with the age of the patients, numbers in the family, therapy methods, patient′s level of discomfort, patient′s disease severity, patient′s level of dependence and the husband′s understanding of the level of severity. 3. Linear correlation analysis on burden: The husbands′ burden is explained in 22.5% by husband′s recognition of level of severity and husbands′ age. 4. There were four patterns of the burden on husbands: both objectve burden and subjective burden were high(pattern I), both of objectve burden and subjective burden were low(pattern II), objective burden was high but subjective burden was low(pattern III), objective burden was low but subjective burden was high(pattern IV). The pattern was correlated with the family income, educational level of the patients and their husbands, therapy methods, patient′s level of discomfort, patient′s disease severity, patient′s level of dependence and husband′s understanding of level of severity. 5. The core category of the caring experience of the husbands with arthritis patients was "companionship". The causal factor was the patients′ experience due to symptoms : physical disfigurement, pain, immobility, limitation of house chores, and limitation of social activities. Contextural factors are husbands′ identification of housework and husbands′ concern about the disease. The mediating factors are economic problems, fear of aging, feeling of limitation and family support. The strategy for interaction is mind control and how to solve emotional stress. The "companionship" resulted from caring activities, participation of household activities, helping patients′ to coping with emotional experience. 6. Companionship is established through the process of entering intervention, and caring state of mind. Entering intervention is the phase of participation of therapy and involvement of houseworks. The caring phase consists of decision on therapy, providing therapy, providing direct care, and taking over the household role of wife. Through caring phase, the changing phase set a stage in which husbands consolidate the relationship with their wives, and are reminded of the meaning of marriage. As a result, in changing phase, husbands′ companionship is enhanced. In conclusion, nursing care of chronic illnesses should include a family member especially the spouse. All information on disease shoud be provided to patients and whole family member. Strong support should also be provided to overcome difficulties in taking over role of other sex. Then the quality of life of patients and families will be much improved.

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A Study on Knowledge, Attitude and Behavior to Sexuality in Middle School Students (중학생의 성에 대한 지식, 태도, 행위에 관한 조사연구)

  • Cha, Eun-Seok
    • Journal of the Korean Society of School Health
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    • v.12 no.2
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    • pp.357-375
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    • 1999
  • The purpose of this study is to find out methods to control, regulate and prevent sexual violence and provide guidelines for sex education in middle school. This study was conducted to examine factors in relation to sexuality, attitudes toward women, experience of sexual contact, frequencies and kinds of pornography with which they had contact, and sex education. For the data collection, a survey was conducted from September 25 to October 1, 1997 by using prepared questionnaires. Questionnaires were given to 503 students from three different kinds of middle schools in Seoul, Boys, Girls, and Coeducation schools. The data analyses used a PC-SAS. Each item was examined by frequencies and percentage. To compare Boys with Girls, I applied a T-test. In addition, with the kinds of school type, I applied anANOVA, ${\chi}^2$. Moreover, For investigating and analyzing each category, I categorized knowledge and attitude of sexuality, with precautionary measures of sexual violence. After that I applied T-test, ANOVA, and a Pearson's correlation for each category. The instruments of this study consisted of 9 domains. (1) General characteristics of the respondents (2) 9 questions about the interaction between he/she and his/her parent. (3) 12 questions, concerning A Scale for Attitudes of Adolescents Toward women(AWSA). (4) 26 questions related to sexual knowledge. (5) 25 questions about sexual attitude (6) strategies for prevention of sexual violence-33 questions (7) 5 questions related to sexual behavior (8) the experience of contact with pronography. (9) the experience of sex-education. The major results were summarized as follows; 1. Like many researches, This study shows that the girls are more eqalitarian than boys. The girls mean ($40.90{\pm}3.67$) is significantly higher than boys ($34.72{\pm}3.77$). Most Koreans have believed that there are many differences between men's roles and women's ones, because of confucianism which had been implied in most thought and ideas since the Lee dynasty. Therefore, the result is not surprising at all. 2. Most students answered correctly the questions of sexual knowledge. The girl's score was higher ($Mean{\pm}SD$ : $48.88{\pm}2.39$) than the boys' ($Mean{\pm}SD$ : $46.95{\pm}3.90$)(p 0.001). Nevertheless, the hypothesis that sexual knowledge influences sexual attitude and its behavior was rejected. 3. When twenty-five questions were asked about sexual attitude, the girl students investigated were found to have a more propre sexual attitude than that of the boys. A significant difference was found between boys and girls(p=0.001). The result shows that a person who has more experience in viewing pornography and who smokes will have a more distorted view of sexuality. 4. There are many students who have experienced of sexual contact. They need to take a sex education program about contraception and prevention of sexually transmitted diseases. Systematic and concrete sex education is one way to lead them to proper sexual behavior. 5. Most respondents rejected stereotyped attitudes towards women. Boys, however, were more likely to accept stereotypes of Women. The girl's mean($Mean{\pm}SD$ : $40.90{\pm}3.67$) is higher than the boys($Mean{\pm}SD$ : $34.72{\pm}3.77$)(p=0.0001). 6. Many boys ignored the rules for prevention of sexual violence. A boy or a girl who has more experience of sexual contact over kiss and sex-typed neglected the rules, too(p=0.001). Today, there is increasing juvenile delinquency related to sexuality. This study provided the basic material for a preventive education system. I believe that a systematic and concrete sex education system can be helpful for adolescents and promote their responsibility as well as cultivate morality about sexuality. As a result, juvenile delinquency can be decreased. This study is basically aimed to provide information for a prevenative education system of sexual violence. Further research is recommended to evaluate programs in schools.

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Determination of Practical Dosing of Warfarin in Korean Outpatients with Mechanical Heart Valves (인공심장판막 치환환자의 Warfarin 용량결정)

  • Lee Ju Yeun;Jeong Young Mi;Lee Myung Koo;Kim Ki-bong;Ahn Hyuk;Lee Byung Koo
    • Journal of Chest Surgery
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    • v.38 no.11 s.256
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    • pp.761-772
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    • 2005
  • Background: Following the implantation of heart valve prostheses, it is important to maintain therapeutic INR to reduce the risk of thromboembolism. The objective of this study was to suggest a practical dosing guideline for Korean outpatients with prosthetic heart valves managed by a pharmacist-run anticoagulation service (ACS). Material and Method: A retrospective chart review was completed for all patients enrolled in the ACS at Seoul National University Hospital from March, 1997 to September, 2000. Patients who were at least 6 months post-valve replacement and had nontherapeutic INR value (less than 2.0 or greater than 3.0) were included. The data on 688 patients (1,782 visits) requiring dosing adjustment without any known drug or food interaction with warfarin were analyzed. The amount of adjusted dose and INR changes based on the INR at the time of the event were calculated. Aortic valve replacements (AVR) patients and mitral or double valve replacement (MVR/DVR) patients were evaluated separately. Result: Two methods for the warfarin dosage adjustment were suggested: Guideline I (mg-based total weekly dose (TWD) adjustment), Guideline II (percentage-based TWD adjustment). The effectiveness of Guideline 1 was superior to Guideline II overall in patients with both AVR and MVR/DVR. Conclusion: The guideline suggested in this study could be useful when the dosage adjustment of wafarin is necessary in outpatients with mechanical heart valves.

The application of photographs resources for constructive social studies (구성주의적 사회과 교육을 위한 사진자료 활용방안)

  • Lee, Ki-Bok;Hwang, Hong-Seop
    • Journal of the Korean association of regional geographers
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    • v.6 no.3
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    • pp.117-138
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    • 2000
  • This study is, from the view point of constructive social studies which is the foundation of the 7th curriculum, to explore whether there is any viable program and to investigate it by which students, using photo resources in social studies, can organize their knowledge in the way of self-directed thinking. The main results are as follows: If it is a principle of knowledge construction process of constructive social studies that individual construction (cognitive construction) develops into communal construction(social construction) and yet communal construction develops itself, interacting with individual construction, it will be meet the objectives of social studies. In social studies, photos are a powerful communication tool. communicating with photos enables to invoke not only the visual aspects but also invisible aspects of social phenomena from photos. It, therefore, can help develop thinking power through inquiry learning, which is one of the emphasis of the 7th curriculum. Having analyzed photo resources appeared on the regional textbooks in elementary social studies, they have been appeared that even though the importance and amount of space photo resources occupy per page is big with regard to total resources, most of the photos failed to lad to self-directed thinking but just assistant material in stead. Besides, there appeared some problems with the title, variety, size, position, tone of color, visibility of the photos, and further with the combination of the photos. Developing of photo resources for constructive social studies is to overcome some problems inherent in current text books and to reflect the theoretical background of the 7th curriculum. To develop the sort of photo that can realize the point just mentioned, it would be highly preferable to provide photo database to facilitate study with homepage through web-based interaction. To take advantage of constructive photo resources, the instruction is strategized in four stages, intuition, conflict, accommodation, and equilibration stage. With the advancement of the era of image culture, curriculum developers are required to develop dynamic, multidimensional digital photos rather than static photos when develop text books.

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Expression of Hypoxia-inducible Factor-1 $\alpha$ in Esophageal Squamous Cell Carcinoma: Relationship to Prognosis and Tumor Biomarkers (식도 편평세포암에시 Hypoxia-inducible Factor-1 $\alpha$의 발현: 예후와 종양표지자와의 상관성)

  • 양일종;김종인;이해영;천봉권;조성래
    • Journal of Chest Surgery
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    • v.37 no.8
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    • pp.691-701
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    • 2004
  • Background: Tissue hypoxia is a characteristic of many human malignant neoplasms, and hypoxia inducible factor-1 (HIF-1) plays a pivotal role in essential adaptive response to hypoxia, and activates a signal pathway for the expression of the hypoxia-regulated genes, resulting in increased oxygen delivery or facilitating metabolic adaptation to hypoxia. Increased level of HIF-1 a has been reported in many human malignancies, but in esophageal squamous cell carcinoma, the influence of HIF-1 a on tumor biology, including neovascularization, is not still defined. Material and Method: The influence of HIF-1 a expression on angiogenic factors, correlation between the tumor proliferation and HIF-1 a expression, interaction of HIF-1 a expression and p53, and correlation between HIF-1 a expression and clinicopathological prognostic parameters were investigated, using immunohistochemical stains for HIF-1 a, VEGF, CD34, p53, and Ki-67 on 77 cases of resected esophageal squamous cell carcinoma. Result: HIF-1 a expression in cancer cells was found in 33 of 77 esophageal squamous cell carcinoma cases. The 33 cases (42.9%) showed positive stain for HIF-1 a. High HIF-1 a expression was significantly associated with several pathological parameters, such as histologic grade (p=0.032), pathological TMN stage (p=0.002), the depth of tumor invasion (p=0.022), regional lymph node metastasis (p=0.002), distant metastasis (p=0.049), and lymphatic invasion (p=0.004). High HIF-1 a expression had significant VEGF immunoreactivity (p=0.008) and Ki-67 labeling index (p<0.001), but was not correlated with microvascular density within tumors (p=0.088). The high HIF-1 a expression was correlated with aberrant p53 accumulation with a marginal significance (p=0.056). The overall 5-year survival rate was 34.9%. The survival rate of patients with a high HIF-1 a expression was worse than that of patients with low-expression tumors (log-rank test, p=0.0001). High HIF-1 a expression was independent unfavorable factors although statistical significance is marginal in multivariate analysis. Conclusion: It is suggested that (1) high HIF-1 a expression in esophageal squamous cell carcinoma is associated with tumor hypoxia, or with genetic alteration in early carcinogenesis and progressive stages, (2) high HIF-1 a expression may be associated with intratumoral neovascularization through HIF-VEGF pathway, and (3) high HIF-1 a expression is associated with poor prognosis in patients with esophageal squamous cell carcinoma and may playa role as biomarker for regional lymph node metastasis.

Expression of Hypoxia-inducible Factor-$1{\alpha}$ in Non-small Cell Lung Cancer: Relationship to Prognosis and Tumor Biomarkers (비소세포 폐암에서 HIF-$1{\alpha}$의 발현: 예후 및 종양표지자와의 관련성)

  • Cho, Sung-Rae;Byun, Joung-Hun;Kim, Jong-In;Lee, Bong-Geun;Chun, Bong-Kwon
    • Journal of Chest Surgery
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    • v.39 no.11 s.268
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    • pp.828-837
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    • 2006
  • Background: Tissue hypoxia is characteristic of many human malignant neoplasm, and hypoxia inducible factor-1(HIF-1) plays a pivotal role in essential adaptive response to hypoxia, and activates a signal pathway for the expression of the hypoxia-regulated genes, resulting in increasing $O_2$ delivery or facilitating metabolic adaptation to hypoxia. Increased level of HIF-$1{\alpha}$ has been reported in many human malignancies, but in non-small cell lung carcinoma the influence of HIF-$1{\alpha}$ on tumor biology, including neovascularization, is not still defined. In present study the relationship of HIF-$1{\alpha}$ expression on angiogenetic factors, relationship between the tumor proliferation and HIF-$1{\alpha}$ expression, interaction of HIF-$1{\alpha}$ expression and p53, and relationship between HIF-$1{\alpha}$ expression and clinico-pathological prognostic parameters were investigated. Material and Method: Archival tissue blocks recruited in this study were retrieved from fifty-nine patients with primary non-small cell lung carcinoma, who underwent pneumonectomy or lobectomy from 1997 to 1999. HIF-$1{\alpha}$, VEGF(vascular endothelial growth factor), and p53 protein expression and Ki-67 labeling index in tumor tissues were evaluated, using a standard avidin-biotin-peroxidase complex(ABC) immunohistochemistry. Relationship between the HIF-$1{\alpha}$ expression and VEGF, p53 overexpression and correlation between the HIF-$1{\alpha}$ expresseion and Ki-67 index were analyzed. Clinico-pathologic prognostic parameters were also analyzed. Result: HIF-$1{\alpha}$ expression in cancer cells was found in 24 of 59 cases of non-small cell lung carcinoma(40.7%). High HIF-$1{\alpha}$ expression was significantly associated with several pathological parameters, such as pathological TMN stage(p=0.004), pT stage(p=0.020), pN stage (p=0.029), and lymphovascular invasion(p=0.019). High HIF-$1{\alpha}$ expression was also significantly associated with VEGF immunoreactivity(p<0.001), and aberrant p53 expression(p=0.040). but was marginally associated with Ki-67 labeling index(p=0.092). The overall 5-year survival rate was 42.3%. The survival curve of patients with a high HIF-$1{\alpha}$ expression was worse than that of patients with low-expression(p=0.002). High HIF-$1{\alpha}$ expression was independent unfavorable factors with a marginal significance in multivariate analysis performed by Cox regression. Conclusion: It is suggested that high HIF-$1{\alpha}$ expression may be associated with intratumoral neovascularization possibly through HIF-VEGF pathway, and high HIF-$1{\alpha}$ expression could be associated with lymph node metastasis and post operative poor prognosis in patients with non-small cell lung carcinoma.

Effects of Instructional Material Using ICT at High School Earth Science (고등학교 지구과학 수업에서 ICT 활용 수업자료의 효과)

  • Lee, Yong-Seob;Kim, Jong-Hee;Kim, Sang-Dal
    • Journal of the Korean earth science society
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    • v.25 no.5
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    • pp.336-347
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    • 2004
  • This study investigated the effects of the application of a variety of ICTs cause the effects on self-directed learning capability, creativity and problem-solving ability. In order to achieve the above aim, Web-Based Instructions(WBI) and instructions using CD-ROM Titles for the unit of 'the solar system and the galaxy' were applicated and analyzed which belongs to the area of 'the earth' in the subject 'science' for high school students. Instructions using WBI materials and CD-ROM titles were found to be effective on 'self-conception', 'creativity', 'future inclination', 'self-assessment ability', 'openness' and' initiative' improvement all of which belong to self-directed learning characteristics. They did not, however, show meaningful effect on improving 'learning eagemess' and 'responsibility' improvement. On looking into self-directed learning characteristics according to prerequisite learning levels, both groups and these for instruction using CD-ROM learning materials were found to have no effect on interaction. With respect to problem-solving ability improvement which is characteristic of the instruction using ICTs, WBI proved more fruitful than instruction using CD-ROM titles on improving scholastic achievement level. WBI was effective on 'fluency', 'originality' and 'resistance to premature closure'. It on the other hand, was of no use on 'abstraction of titles' and 'elaborateness' These results came from the following characteristics: WBI came into effect on 'fluency' and 'originality' in the areas of variety and vitality, which are characteristic of WBI. In the area of resistance to premature closure WBI was effective on organizing learning contents owing to the animation of picture materials which are variously presented in the web site. As a result of WBI questionnaire about WBI, an excellent effect on the structure of display, quantity of information, indication and instruction, supplementary study and further study were discussed.

POLYMERIZATION SHRINKAGE OF COMPOSITE RESINS CURED BY VARIABLE LIGHT INTENSITIES (가변 광도 중합에 따른 복합레진의 중합수축에 관한 연구)

  • Lim, Mi-Young;Cho, Kyung-Mo;Hong, Chan-Ui
    • Restorative Dentistry and Endodontics
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    • v.32 no.1
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    • pp.28-36
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    • 2007
  • The purpose of this study was to compare the effect of exponential curing method with conventional curing and soft start curing method on polymerization shrinkage of composite resins. Three brands of composite resins (Synergy Duo Shade, Z250, Filtek Supreme) and three brands of light curing units (Spectrum 800, Elipar Highlight, Elipar Trilight) were used. 40 seconds curing time was given. The shrinkage was measured using linometer for 90 seconds. The effect of time on polymerization shrinkage was analysed by one-way ANOVA and the effect of curing modes and materials on polymerization shrinkage at the time of 90s were analysed by two-way ANOVA. The shrinkage ratios at the time of 20s to 90s were taken and analysed the same way. The results were as follows : 1. All the groups except Supreme shrank almost within 20s Supreme cured by soft start and exponential curing had no further shrinkage after 30s (p < 0.05). 2. Statistical analysis revealed that polymerization shrinkage varied among materials (p = 0.000) and curing modes (p = 0.003). There was no significant interaction between material and curing mode. 3. The groups cured by exponential curing showed the statistically lower polymerization shrinkage at 90s than the groups cured by conventional curing and soft start curing (p < 0.05). 4. The initial shrinkage ratios of soft start and exponential curing were statistically lower than conventional curing (p < 0.05). From this study, the use of low initial light intensities may reduce the polymerization rate and, as a result, reduce the stress of polymerization shrinkage.

Effect of Types of Egg Shell Calcium Salts and Egg Shell Membrane on Calcium Metabolism in Rats (난각 칼슘염의 종류와 난막의 존재유무가 흰쥐의 칼슘대사에 미치는 영향)

  • Noh, Kyung-Hee;Lee, Sang-Hyun;Ma, Jie;Zhou, Yusi;Kim, Jae-Cherl;Kim, Myo-Jeong;Song, Young-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.7
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    • pp.853-859
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    • 2006
  • This study was carried out to investigate the effect of egg shell calcium salt types and egg shell membrane on calcium metabolism in rats. Sprague-Dawley male rats, 4 weeks of age, were fed on free-calcium diets for 2 weeks after adjustment period. Rats weighing approximately $247{\pm}2.3g$ were divided into 6 groups and were fed on the experimental diets containing 0.2% calcium for 4 weeks. Experimental groups were as follows; {ES(M+)} (egg shell powder diet with egg shell membrane), {ES(M-)} (egg shell powder diet without egg shell membrane), {AC(M+)} (egg shell calcium acetate diet with egg shell membrance), {AC(M-)} (egg shell calcium acetate diet without eg shell membrane), {GC(M+)} (egg shell calcium glucuronate diet with egg shell membrane) and {GC(M-)} (egg shell calcium glucuronate diet without egg shell membrane). Bone length of femur was significantly different by the types (p<0.05) of egg shell calcium salts. Bone mineral density of femur showed the highest level in AC(M-) group. Calcium content of femur and calcium absorption rate were higher in egg shell calcium salt groups than in eg shell powder groups. Calcium absorption rate and retention were significantly different (p<0.05) among the types of eg shell calcium salts and were higher in the AC(M-) group than in the other groups. Alkaline phosphatase activity, parathyroid hormone and osteocalcin levels of serum showed no significant difference among the experimental groups. From the above results, it is concluded that bioavailability of calcium is higher in groups of egg shell calcium salts compared to those in egg shell powder, even though egg shell membrane has no effect on calcium metabolism. Thus, these findings suggest the possibility of using egg shell calcium salts as a functional food material related to calcium metabolism.