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A Prospective Study on Attitude of Professional Student toward Population Related Issues in Korea (대학전공별(大學專攻別) 전문직학생(專門職學生)들의 인구관련문제(人口關聯問題)에 대한 연차적(年次的) 변화(變化) 연구(硏究))

  • Lee, Kyung-Sik;Kim, Hwa-Joong
    • Journal of Preventive Medicine and Public Health
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    • v.9 no.1
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    • pp.11-24
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    • 1976
  • This study was a part of large scale of a prospective study on attitudes of professional students in medicine, nursing and teaching toward population related issues in Korea. The study was first conducted in May 1974 and then in May 1975 for the 1974 class cohot using a questionaire consisted of attitude scales and other items developed by Lee. The purpose of stuay was twohold, namely, to determine the difference in students among specializations on one hand and between the first and second years in the 1974 class cohot regarding tile subject matter. A one-way analysis of variance was used for attitude scale, and absolute and relative frequency were computed for the analysis of non-attitude scale items by employing Fishers' Ratio and Duncan's multiple range test at 5% level and chi square test at 5% level as significance tests. The hypothesis 'students in health profession are more likely to have positive attitudes toward population related issues progressively as class year advances than students in teaching profession' was tested and the following results were obtained: 1) Nursing students were more likely to display favarable attitudes toward family planning than medical or teaching students although the class cohot showed slightly negative improvement in the second year. Medical and teaching students apperaed to have slightly improved attitudes in the second year. 2) Respondents in general perceived national family planning program as a means of population control and this tendency was more true among nursing students as the class year advances than two other professional groups of students. Students in teaching profession appeared to perceive it more as a means to improve individual family welfare while health students were likely to see as to improve maternal and child health. This tendency was progressively improved as the class year advanced. 3) The majority of students regardless of their respective specializations believed that family planning program should be directed toward the improvement of individual family welfare. No progressive changes in the class cohot were observed. 4) About the plan to use contraceptives in future, no singnificant differences were observes among different specializations nor in different class years. However, the majority was confirmed to have a plan to use contracepives in future. An increasing proportion of the undecided category was observed, as class year advanced among health students. 5) Students in health profession were found to be more favorable about 'more leisure opportunities' as motive for limiting number of children whereas education students indicated the reasons as 'facilitate ambitions' and 'economic base' The progressive changes toward positive direction in both groups were observed as the class years advanced. 6) Attitudes toward induced abortions of the health students were observed to be positively related to class years while an inverse relationship was found in teaching students who showed much less favor in the subject matter than health students. This phenomenon may be due to the different exposure to learning environments unique to respective specializations. 7) Health students were found to have more favorable attitudes toward population education in general than the teaching students. The teaching students appeared to have changed more to the negative direction when they became the second year while no such development was observed in health students. The teaching students seemed to hold a very conservative position with regard to sex education in schools. 8) About the equality of sexes, the nursing group was found to be most favorable while the reverse was true in the teaching group. A change in the negative direction as the class year advanced was found in the teaching group. 9) About questions related to fertility values-the 10 percent of respondents regardless of specialization indicated that they would maintain their single status in future, however no change was observed in the second year. The desired number of children was found to be two by the majority of students in nursing, medicine and teaching in order of high proportion. No changes in a different class year were observed. The childless marriage was seen by nursing students as a problem more than other students, but a slight change in positive direction was found when the nursing students became the second year. In summing, as data supported in the above, students in health profession demonstrated more favorable attitudes toward population related issues than the teaching students and this tendency became more apparent in the second year. It was noticed that health students were more conscious about the health aspect of population and family planning program while the teaching students gave more attention to the socioeconomic aspect. The sex variable seemed to have operated in the item related to the equality of sexes. In conclusion, as data presented in the above, the hypothesis of this study was accepted except in the few items. It should be noted that the limitation of this study is the short duration of the observation in measuring the possible attitude changes. It should include curriculum analysis for the respective specializations in order to indentify the area of curriculum impact on students in future study.

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A Study on the Frequency of Falls, Fear of Falling, and Perceived Health Status according to Cognitive Function in Community-dwelling Elderly Women (지역사회 여성노인의 인지기능에 따른 낙상발생빈도, 낙상두려움 및 지각된 건강상태)

  • Shin, Kyung-Rim;Kang, Younhee;Jung, Dukyoo;Kim, Miyoung;Yun, Eun-Suk;Ma, Rye-Won
    • 한국노년학
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    • v.31 no.4
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    • pp.1155-1167
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    • 2011
  • The purpose of this study was to investigate the frequency of falls, fear of falling, perceived health status, and number of disease according to cognitive function in community-dwelling the elderly women. This study utilized a descriptive survey design. Data were collected for six months with 311 elderly women who visited in public health center at S city. After obtaining Institutional Review Board(IRB) approval, a face-to-face, and private interview was conducted with each participant who was eligible and agreed to participate in this study by trained graduate-level nursing students. The questionnaires consisted of MoCA-K, K-MMSE, Fall Efficacy Scale, PHS scale. The collected data were analyzed with SPSS/WIN 17.0 program, which was used descriptive statistics, Chi-Square test and t-test, Correlation. The major findings of this study were as follows; 1) The average age of the subjects was 71.68±5.13 and cognitive function score was 22.14±4.32. approximately 35% of participants had fallen within one year. 2) there were significant differences in perceived health status according to cognitive function. 3) fear of fall and cognitive function, perceived health status and cognitive function were significant correlation. In conclusion, this study will contribute to establish strategies for preventing fall. Interventions for fall prevention and fear of fall enhancement should be developed with the consideration of the level of cognitive function in the elderly. Reducing the fear of falling through the comprehensive nursing intervention will ultimately improve the quality of life in the elderly.

Studies on the Breeding of Cold Hardiness and Technique of Overwintering Cultivation in Citrus (감귤(柑橘)의 내한성(耐寒性) 품종육성(品種育成) 및 내한(耐寒) 재배기술(栽培技術)에 관(關)한 연구(硏究))

  • Kim, Chi-moon;Song, Ho-kyung;Kim, Chung-suk
    • Korean Journal of Agricultural Science
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    • v.4 no.2
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    • pp.126-140
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    • 1977
  • Present studies were carried out for breeding cold resistant clones of Citrus, improving overwintering techniques of Citrus in Jeju island as well as other southern region, Result obtained were as follows 1. In the vinyl house covered with two sheets of straw mat, 12 indivuals were found as non-injury and 15 were slightly injured by leaf freeging test at $-9^{\circ}C$ for 2 hours treatment. 2. In the condition of vinyl house covered with straw mat and viny film mulching and heat-in by sun-light, the inside temperature of vinyl house were not lowered below $-3^{\circ}C$ and the ground temperatura in vinyl house keeps above $0^{\circ}C$ during winter though outdoor temperature were lower by $-15^{\circ}C$(Daejeon area). 3. The vinyl tunnel inside the vinyl house and vinyl film mulching on ground position showed greater effectiveness for preventing heat loss from house but there were no significant difference between the color of vinyl film covered the tunnel. 4. In the vertical distribution of maximum temperature in vinyl house, the upper space was slightly higher than the lower position at high temperature condition, while minimum temperature was distributed as higher as the middle position, ground surface and upper position in order at low temperature condition 5. In the horizontal distribution of temperature in vinyl house, ground and surface-temperature of north side was lower than the other sides, and citrus planted within 30cm from north side wall died by cold injury and in the other side near wall appeared slight symptom of cold injury. 6. The insulating trench ($30{\times}30{\times}30cm$) packed with straw bundle installed under north wall might be effective to prevent heat loss of ground temperature. 7. In cloudy and snowy day, the temperature difference between indoor and outdoor were less, and the indoor temperature were maintained highly during night due to the effect of prevention of heat loss. 8. The highest temperature in a day was observed at about P.M. 3 both inside and outside of vinyl house and the lowest temperature was observed at about A.M. 6. The difference between the highest and lowest temperature of indoor in a sunny day was $19^{\circ}C$, compared with $9^{\circ}C$ on a cloudy or snowy day in late November. Especially, lowering of temperature in a snowy day was so less that the curve of temperature change was comparatively constant, 9. If the effective methods of citrus cultivation in vinyl house with improved clone such as hardiness. semi-dwarf and spur type are applied, it might be possible to cultivate the citrus tree safely in Jeju island as well as other southern rejion and to magnity the cultivation of citrus tree.

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Cephalometric Characteristics of TMD Patients based on RDC/TMD Axis I Diagnosis (RDC/TMD Axis I 진단에 따른 측두하악장애 환자의 측두 두부방사선적 특징에 관한 연구)

  • Ahn, Ji-Yeon;Kim, Yong-Woo;Kim, Young-Ku;Lee, Jeong-Yun
    • Journal of Oral Medicine and Pain
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    • v.36 no.1
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    • pp.39-51
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    • 2011
  • The aims of this study were to investigate whether the facial skeletal patterns previously reported to be related to temporomandibular disorder (TMD) in other studies could be consistently observed in the TMD patients diagnosed according to Research Diagnostic Criteria for Temporomandibular Disorder (RDC/TMD) Axis I and evaluate its usability in the orthodontic clinics to examine the patients with TMD related symptoms. The clinical records and radiographs of female patients who visited the TMD and Orofacial Pain Clinic of Seoul National University Dental Hospital and were diagnosed as TMD were consecutively filed for this study. Patients were clinically examined and diagnosed according to the revised diagnostic algorithms of RDC/TMD Axis I and the lateral cephalogram, panoramic orthopantomogram, temporomandibular joint (TMJ) orthopantomogram, and transcranial radiograph of each patient were taken and digitalized. The data of patients who were under 18 years of age or had any systemic disease, trauma history involving the TMJ, or skeletal deformity at the time of the first examination were excluded. The remaining data of 96 female patients were finally analyzed. The obtained results were as follows: 1. There are no significant differences of cephalometric measurements between RDC I (muscle disorders) diagnostic groups. 2. Only the articular angle of the RDC group IIc (disk displacement without reduction without limited opening) patients was larger than patients of the no diagnosis of RDC II group (disk displacement). 3. Larger articular angle and smaller facial height ratio were observed in RDC IIIc group (osteoarthrosis) compared to IIIa group (arthralgia). Larger articular angle, larger Bjork sum, smaller posterior facial height, and smaller facial height ratio were observed in RDC group IIIc compared to no diagnosis of RDC III group (arthralgia, arthritis, and arthrosis). 4. According to the results of cephalometric analysis in simplified RDC groups, smaller overjet was observed in muscle disorders (MD) group. Facial height ratio and IMPA were smaller and articular angle was larger in disk displacements (DD) group than in no diagnosis of DD group. In arthrosis (AR) group, posterior facial height, and facial height ratio were smaller, and articular angle, gonial angle, facial convexity, FMA, Bjork sum, and ANB were larger than in no diagnosis of AR group. In joint pain (JP) group, only posterior facial height was smaller than no diagnosis of JP group. In conclusion, Facial morphologic patterns showing posterior-rotated mandible and lower posterior facial height is related to RDC group II and III diagnosis of the TMJ in female TMD patients. RDC/TMD Axis I diagnosis can provide a good clinical diagnostic tool for the standardized examination of the TMJ in orthodontic clinics.

A Phase I/II Trial of $DCVac/IR^{(R)}$ Dendritic Cell Immunotherapy Combined with Irradiation in Cases of Refractory Colorectal Cancer with Multiple Liver Metastases (기존의 치료에 반응하지 않는 다발성 간전이 대장암 환자에서 방사선조사와 병합한 수지상세포 면역치료의 1, 2상 임상시험)

  • Choi, Young-Min;Lee, Hyung-Sik;Kwon, Hyuk-Chan;Han, Sang-Young;Choi, Jong-Cheol;Chung, Ju-Seop;Kim, Chang-Won;Kim, Dong-Won;Kang, Chi-Duk
    • Radiation Oncology Journal
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    • v.26 no.2
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    • pp.104-112
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    • 2008
  • Purpose: To assess the toxicity and tumor response induced by $DCVac/IR^{(R)}$ dendritic cell(DC) immunotherapy combined with irradiation for refractory colorectal cancer patients with multiple liver metastases. Materials and Methods: Between May 2004 and November 2006, applicants from a pool of refractory colorectal cancer patients with multiple liver metastases were enrolled. The patients were registered after having signed the informed consent form, which had been approved by the Institutional Review Board from the Dong-A University and Busan National University Hospital. DCs were obtained from peripheral blood of each patient, and then cultured in vitro. A total of $6{\times}10^6$ DCs were packed into a vial($DCVac/IR^{(R)}$, 0.5 ml) at the convenience of each patient's schedule. On the day before and on the day of each vaccination, each patient received a 4 Gy radiation dose to the target tumor. On the day of vaccination, the indicated dose of autologous DCs was injected into the irradiated tumor using ultrasound-guided needle injection procedures. A total of four vaccinations were scheduled at three 2-week intervals and one 4 week interval at the Dong-A University and Busan National University Hospital. If the tumor status was deemed to be stable or responding to therapy, an additional vaccination dose or two was approved at 4 week intervals beyond the fourth immunization. A tolerance test for DCs was conducted by injecting a range of doses($3{\times}10^6\;to\;12{\times}10^6$ DCs) after the 3rd injection. Moreover, the maximal tolerable dose was applied to additional patients. Treatment safety was evaluated in all patients who had at least one injection. Treatment feasibility was evaluated by the 10th week by assessing the response of patients having at least 4 injections. For systemic toxicities, the evaluation was performed using the National Cancer Institute Common Toxicity Criteria, whereas adverse effects were recorded using common WHO toxicity criteria. Results: Of the 24 registered patients, 22 received the DCs injections. Moreover, of the 14 patients that applied for the tolerance test, only 11 patients completed it because 3 patients withdrew their testing agreement. A grade 3 or more side effect, which was possibly related to the DC injection, did not occur in additional patients. The $12{\times}10^6$ DC injection was identified as the maximum tolerable dose, and was then injected in an additional 8 patients. Patients tolerated the injection fairly well, with no fatal side effects. In order to assess the feasibility of DC immunotherapy, the response was evaluated in other hepatic lesions outside of the targeted hepatic lesion. The response evaluation was performed in 15 of the 17 patients who received at least 4 injections. Stable and progressive disease was found in 4 and 11 patients, respectively. Conclusion: The DC-based immunotherapy and radiotherapy is theoretically synergistic for the local control and systemic control. The $DCVac/IR^{(R)}$ immunotherapy combined with irradiation was tolerable and safe in the evaluated cases of refractory colorectal cancer with multiple liver metastases. Future work should include well designed a phase II clinical trials.

The Effect of Pleural Thickening on the Impairment of Pulmonary Function in Asbestos Exposed Workers (석면취급 근로자에서 늑막비후가 폐기능에 미치는 영향)

  • Kim, Jee-Won;Ahn, Hyeong-Sook;Kim, Kyung-Ah;Lim, Young;Yun, Im-Goung
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.923-933
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    • 1995
  • Background: Pleural abnormality is the the most common respiratory change caused by asbestos dust inhalation and also develop other asbestos related disease after cessation of asbestos exposure. So we conducted epidemiologic study to investigate if the pleural abnormality is associated with pulmonary function change and what factors are influenced on pulmonary function impairment. Methods: Two hundred and twenty two asbestos workers from 9 industries using asbestos in Korea were selected to measure the concentration of sectional asbestos fiber. Ouestionnaire, chest X-ray, PFT were also performed. All the data were analyzed by student t-test and chi-square test using SAS. Regressional analysis was performed to evaluate important factors, for example smoking, exposure concentration, period and the existence of pleural thickening, affecting to the change of pulmonary function. Results: 1) All nine industries except two, airborn asbestos fiber concentration was less than an average permissible concentration. PFT was performed on 222 workers and the percentage of male was 88.3%, their mean age was $41{\pm}9$ years old, and the duration of asbestos exposure was $10.6{\pm}7.8$ yrs. 2) The chest X-ray showed normal(89.19%), pulmonary Tb(inactive)(2.7%), pleral thickening (7.66%), suspected reticulonodular shadow(0.9%). 3) The mean values of height, smoking status, concentration of asbestos fiberwere not different between the subjects with pleural thickening and others, but age, cumulative pack-years, the duration of asbestos exposure were higher in subjects with pleural thickening. 4) All the PFT indices were lower in the subjects with pleural thickening than in the subjects without pleural thickening. 5) Simple regression analysis showed there was a significant correlation between $FEF_{75}$ which is sensitive in small airway obstruction and cumulative smoking pack-years, the duration of asbestos exposure and the concentration of asbestos fiber. 6) Multiple regression analysis showed all the pulmonary function indices were decreased as the increase of cumulative smoking pack-years and especially in the indices those are sensitive in small airway obstruction. Pleural thickening was associated with reduction in FVC, $FEV_1$, PEFR and $FEF_{25}$. Conclusion: The more concentration of asbestos fiber and the more duration of asbestos exposure, the greater reduction in $FEF_{50}$, $FEF_{75}$. Therefore PFT was important in the evaluation of early detection for small airway obstruction. Furthermore pleural thickening without asbesto-related parenchymal lung disease is associated with reduction in pulmonary function.

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Perceived Weight and Health Behavior Characteristics -Normal and Overweight Middle-aged women- (도시일부 중년여성의 체중상태와 건강행위 선택 비교 연구)

  • 조현숙
    • Journal of Korean Academy of Nursing
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    • v.26 no.2
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    • pp.387-398
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    • 1996
  • The objective of this study was to clarify whether there are any differences between normal and over-weight middle-aged(40∼59yrs)women in their perceived weight, health status, health conception and health behavior choices. The sample consisted of 39 normal weight and 55 over-weight (11% above on the Body Index Scale) women who live in Juan, Inchon. The Participants were randomly selected in each weight group considering socio-demographic factors. The findings from this study are summarized below. 1) Among the 55 overweight middle-aged women, 16 were above 20% on the Body Index Scale and 14 were above 30%. Twenty-five(45.5%) of the overweight group and 12(30.8%) of the normal weight group had one disease, and there were 12(21.8%) in the overweight group and 8(20.5%) in the normal weight group where one of the family members had a disease, but these differences were not statistically significant. The average monthly family income for the overweight group was ₩l,880,000 compared to ₩2,140, 000 for the normal weight group, but this difference was also not significant. The age range for the whole group was between 40 and 59(mean=46.8 for total, 48.6 for overweight and 45.7 for normal weight group). Again no significant difference found. Occupations were housemaker 53(56.4%), private business(13.8%), salarywoman(9.6%), and teacher (2.1%). Thirty housemaker(54.5%) from the overweight group and 23(59%) from the normal group did not constitute a statistically significant different. For the educational status, 34(61.8%) of the overweight women and 33(84.6%)of the normal weight group finished high school or more educational courses, but there was no significant statistical difference. Eleven(20.0%) of the overweight women and 5(12. 8%) of the normal weight group were single, but again no significant statistical difference was found. 2) A test for difference in health characteristics between two weight groups indicated that two groups do not show statistical differences in their perceived health status, health conception or health behavior choice. That is, the overweight group, also perceive their health status as good as the normal group, and regard ‘Health’ as a state that enables them to carry out social roles and functions rather than as the traditional concept of health as no disease or no symptoms. Moreover. the overweight group selected their health behaviors not for the prevention of diseases or maintenance of health but for promotion of health. To determine if no statistical difference might be related to the overweight group's failure of perceive themselves as overweight, the perceived and objective overweight status were compared by the chi-square analysis, and no difference was found(X/sup²=49.37, df=1, p=.000). However, 7(17.9%) of the normal group perceived themselves as being overweighted and 7(12.7%) of the overweight group thought they were of normal weight. Even though the overweight group employed in this study perceived themselves as being overweight, they regarded themselves as healthy as those in the normal weight group. It was shown that there was no statistical difference between two groups in health conception, and that they chose health behaviors to promote health status. 3) Perceived health conception was shown to be significantly related to health behavior choice (r= .28, p=.006 for whole group : r=.33, p=.014 for overweight group : and r=.12. p=.463 for normal group) .There was an indication that the more complicated the perceived health conception was, the more the trend of health behavior choice to promote health. This was especially true for the overweight group. But, the perceived health status did not related to health behavior choice statistically(r=.13, p=.202), and it was thought that reasons for selecting health behaviors were not related to their health status. That is, the overweight group perceive themselves as healthy as the normal weight group or thought that overweight itself does not incur any risk on their health. Data from two groups were combined and analyzed with multiple regression methodology, because the relationship pattern of the two groups was similar. The analysis showed that health behavior has a significant relationship with age and the perceived health conception(r/sup²=.1517, p=.05, F=8.133). It means they come to health behavior along with their health conception and their age rather than their weights, perceived weight, health status or other social characteristics. This study was intended to understand how overweight middle-aged women perceive ‘weight’ and ‘health’, and how they meet their health related needs in comparison with normal weight middle-aged women. Other factors related to the health behavior in overweight middle-aged woman need to be determined through further descriptive studies outlined in the following recommendations. a) Reseach with the study area expanded. b) Reseach with grouping more detailed : much more overweight and underweight group c) Reseach on restricted relationship between overweight and age or profession. d) Reseach on what overweight middle-aged women do to reduce their weight and what factors motivate them to do it

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The Impact of the Oral-Health Education Experiences of Elementary School Teachers on Their Oral-Health Awareness and Attitude (초등교사의 구강보건교육 경험에 따른 구강보건 인지 및 태도)

  • Jang, Jong-Hwa;Jang, Sun-Hee;Kim, Mi-Jeong;Lee, Ji-Youn;Jang, Yun-Jung
    • Journal of Korean society of Dental Hygiene
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    • v.1 no.2
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    • pp.227-242
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    • 2001
  • The purpose of this study was 10 examine whether or not the dental- health education experiences of elementary school teachers have any influence on their oral-health awareness and attitude. The subjects in this study were 414 selected teachers from Seoul and North Cholla province. The instrument used by Lee Heung-su was modified into self- reporting questionnaire, and the schools where the subjects were working were visited to conduct a survey for 28 days from September 15 to October 13, 2000. For data analysis, SPSS was employed, and chi-squre, t-test and ANOVA were implemented. The findings of this study could be listed as below: 1. 184(44.4%) out of the techers investigated had ever been educated in dental health, and 230 teachers(55.6%) hadn't. 47% replied they hadn't received oral-health education for the lack of education opportunities. 2. In regard to dental-health awareness and attitude. the presence or absence of dental-health education experiences didn't make any difference to their daily toothbrushing frequency(p>0.05). The use of fluorine was significantly different between the groups(p<0.01), as 42.9% of the teachers with dental-health education experiences and 63.9% of the others with no such a experience didn't use that, 45.7% of the former group and 29.1 % of the latter accurately knew how to brush teeth, and the difference between the two was significant (p<0.01). 3. Concerning student-related dental-health awareness and attitude, the dental-health education experiences make 45.7% of the educated group and 31.7% of the uneducated group agreed to the strong need for oral examination, and the gap between the two was significant(p<0.01). 90.8% of the former group gave counsel to students on dental health, and 77.2% of the latter didn't. The gap between the two was significant as well (p<0.01). 77.2% of the educated group and 41.3% of the uneducated group offered frequent dental-health education, and the difference between the two was significant (p<0.01). 4. Their awareness of the fluorine-based toothbrushing project differed significantly by region(p<0.05), as the teachers from North Cholla province recognized it better than those from Seoul. The female teachers provided more education regarding that project, and those who were older or had more teaching experiences were more aggressive in instructing that project(p<0.01). And the married teachers took more forward attitude than the unmarried (p<0.01). By school location, the teachers from Seoul showed more active attitude than those from North Cholla province(p<0.01), and the gap between the two was significant. As to cooperation, those who were older or had more teaching experience were more cooperative, and the married teachers joined forces better than the unmarried. The gap was significant (p<0.01). 5. Concerning the awareness and attitude of the fluorine-based toothbrushing project, the educated teachers took more aggressive attitude, and the difference between the two was significant(p<0.01). The above-mentioned findings suggested that the dental-health awareness and attitude of the elementary school teachers were under a lot of influence of their oral-health education experiences, and there is a need to develop and carry out education programs for teacher.

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A Longitudinal Trend Analysis in Scientific Knowledge Achievement Progress (초.중.고 학생들의 과학 지식 성취 수준 추이 분석을 위한 종단적 연구)

  • Kwon, Jae-Sool;Choi, Byung-Soon;Kwon, Chi-Soon;Yang, Il-Ho;Lee, Gyoung-Ho;Kim, Ji-Na
    • Journal of The Korean Association For Science Education
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    • v.19 no.2
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    • pp.185-193
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    • 1999
  • The long term trend of studensts' science achievement is a very important factor to check the effectiveness of science educational policy. However, up to date no such effort to understand the trend of Korean students' science achievement has been put into action. Recently, the Science Education Center in Korea National University of Education has been attempted to collect nation wide data for students' science achievement. The first part of the effort was to develop item pools. This study was the second part to collect nation wide data and to check any change during the two year time interval. In this study, the item pools developed by Kwon et. al.(1998) were used with some modification. The data were collected two times; February 1997 and March 1999. The subjects collected nationally were 8,766 students in 1997 and were 4,398 in 1999. The subjects were collected randomly but stratified by region and sex. As the results, the trends of achievement change during the two years were different from elementary to high school. The achievement scores were decreased in elementary schools and increased in high school. In case of middle schools, the change was not significant. However, even in elementary schools the knowledge on theory was increased significantly while knowledge on facts and principles were decreased. In contrast, the knowledge on fact showed the most increase in high schools. In this study, the data were analysed in light of region, sex, behavioral objective levels(ability) and context of test items. The science achievement monitoring system developed by the Science Education Center in Korea National University of Education can be an effective tool for monitoring students' achievement on the national level.

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Preparation of Na-X and Na-A Zeolites from Coal Fly Ash in a Thermoelectric Power Plant and Comparison of the Adsorption Characteristics for Cu(II) with a Commercial Zeolite (화력발전소 석탄비산재를 이용한 Na-X와 Na-A 제올라이트 제조 및 상업용 제올라이트와의 Cu(II) 흡착 특성 비교)

  • Choi, Yu-Lim;Angaru, Ganesh Kumar Reddy;Kim, Dong-Su;Ahn, Hye-Young;Kim, Dae-Ho;Choi, Chi-Dong;Reddy, Kodoru Janardhan;Yang, Jae-Kyu;Chang, Yoon-Young
    • Applied Chemistry for Engineering
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    • v.30 no.6
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    • pp.749-756
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    • 2019
  • Na-X and Na-A zeolites that give high adsorption capacity for heavy metals in an aqueous system were synthesized from the coal fly ash obtained from a thermoelectric power plant using a fusion method. The characteristics and Cu(II) adsorption capacity of the synthetic zeolites were also compared to those of using a commercial zeolite. For the selection of optimum conditions of zeolite synthesis, the effects of major parameters in the fusion method such as a dosage ratio of NaOH, aging time, hydrothermal reaction time, and also the dosage ratio of NaAlO2 (Na-A) on the characteristics and Cu(II) adsorption capacity of the synthetic zeolites were studied. For the analysis of characteristics of the synthetic zeolites, X-ray diffraction (XRD), cation exchange capacity (CEC), Brunaue-Emmett-Teller (BET) and scanning electron microscopy (SEM) were used. The optimum conditions for the synthesis of zeolites with a high adsorption capacity for cationic heavy metals including Cu(II) were the aging time of 6 h, hydrothermal reaction time of 6 h and NaOH and NaAlO2 dosage ratio of 1.5 and 0.5 (Na-A), respectively. According to the Langmuir isotherm test, maximum Cu(II) adsorption capacities of the synthetic and commercial Na-X and Na-A zeolites were found to be 90.1, 105.26, 102.05, and 109.89 mg/g, respectively. This indicates that the adsorption capacity of synthetic zeolites was comparable to commercial ones. The results of this study also suggest that the coal fly ash can be potentially used as a raw material for the zeolite synthesis.