• Title/Summary/Keyword: Analysis of Factors

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Structure of the Phytoplanktonic communities in Jeju Strait and Northern East China Sea and Dinoflagellate Blooms in Spring 2004: Analysis of Photosynthetic Pigments (봄철 제주해협과 동중국해 북부해역에서 식물플랑크톤의 광합성 색소분석을 이용한 군집 분포 특성과 dinoflagellate 적조)

  • Park, Mi-Ok;Kang, Sung-Won;Lee, Chung-Il;Choi, Tae-Seob;Lantoine, Francois
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.1
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    • pp.27-41
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    • 2008
  • Distribution characteristics of phytoplankton community were investigated by HPLC and flow cytometry in Jeju Strait and the Northern East China Sea (NECS) in May 2004, in order to understand the relationship between physical environmental factors and distribution pattern of phytoplankton communities. Based on temperature and salinity data, three distinct water masses were identified; warm and saline Tsushima Warm Current (TWC), which is flowing from northwest of Jeju Island, warm and low saline water at the center of Jeju Strait, which is originated from China Coastal Water (CCW) and relatively cold and high saline water originated from Yellow Sea at the bottom of the Jeju Strait. At Jeju Strait, less saline water (<33 psu) of 15 km width occupied surface layer up to 20 m which located at 20 km offshore and strong thermal front between warm and saline water and cold and less saline water was found in the middle of the Jeju Strait. Vertical transect of temperature and salinity at the NECS also showed that low saline (<33 psu) water occupied the upper 20 m layer and cold and saline water was present at the eastern part. Chl a was measured as $0.06{\sim}3.07\;{\mu}g/L$. Spring bloom of phytoplankton was recognized by the high concentrations of Chl a at the low saline water masses influenced by the CCW and subsurface chlorophyll maximum layer appeared between $20{\sim}30\;m$ depth, which was at thermocline depth or below. Abundances of Synechococcus and picoeukaryote were $0.2{\sim}9.5{\times}10^4\;cells/mL$ and $0.43{\sim}4.3{\times}10^4\;cells/mL$, respectively. Dinoflagellate, diatom and prymnesiophyte were major groups and minor groups were chlorophyte+prasinophyte, chrysophyte, cryptophyte and cyanophyte. Especially high abundance of dinoflagellate was identified by high concentration (>1\;{\mu}g/L$) of peridinin at the bottom of the thermocline, which showed an outbreak of red tide by high density of dinoflagellates. Abundances of picoeukaryote in Jeju Strait were about $5{\sim}10$ times higher than abundance measured in Kuroshio water and showed a good correlation with Chl b (Pras+Viola), which implies the most of population of picoeukaryote was composed of prasinophytes. Prochlorococcus was not detected at all, which suggests that Kuroshio Current did not directly influenced on the study area. Based on the strong negative correlations between biomass of phytoplankton (Chl a) and temperature+salinity, the primary production and biomass of phytoplankton in the study area were controlled by the nutrients supply from CCW.

Soil Contamination of Heavy Metals in National Industrial Complexes, Korea (국내 주요 국가산업단지에서 중금속에 의한 토양오염)

  • Jeong, Tae-Uk;Cho, Eun-Jeong;Jeong, Jae-Eun;Ji, Hwa-Seong;Lee, Kyeong-Sim;Yoo, Pyung-Jong;Kim, Gi-Gon;Choi, Ji-Yeon;Park, Jong-Hwan;Kim, Seong-Heon;Heo, Jong-Soo;Seo, Dong-Cheol
    • Korean Journal of Environmental Agriculture
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    • v.34 no.2
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    • pp.69-76
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    • 2015
  • BACKGROUND: Contamination of soils by heavy metals is the serious environmental problem. In particular, industrial processing is one of the main sources of heavy metal contamination. The objective of this study was to investigate the distribution characteristics of heavy metals in soils collected from industrial complex. METHODS AND RESULTS: In this study, the soil contamination and enrichment factor (EF) of heavy metals were investigated in three national industrial complexes such as Yeosu, Ulsan and Sihwa Banwal industrial complexes. The target heavy metals includes Cd, Cu, As, Hg, Pb, Cr, Zn, and Ni. The results showed that the contents of Cd, Hg, Pb, Zn and Ni in Yeosu and the contents of Cu, As and Cr in Sihwa Banwal were higher than in any other industrial complex. The results of principal component analysis(PCA) in Yeosu, Ulsan and Sihwa Banwal complex could be explained up to approximately 81.4, 69.1 and 70.9% by two factor, respectively. Enrichment factors of Cd, Pb and Zn in all the investigated industrial complexes were above 1.0 that was the value judged to be a high contamination. And EF of Cr was above 1.0 in Sihwa Banwal complex. EF of Zn in all sites was generally high from the other heavy metals. CONCLUSION: Therefore, soils maybe significantly affected by heavy metals (especially, Cd, Pb and Zn) present in the emissions from industrial complexes.

Studies on the Biological Control of Pine Caterpillar (Dendrolimus spectabilis Butler) by Red Wood Ants (Formica rufa truncicola var. yessoensis Forel) (불개미를 이용한 송총의 생물적방제에 관한 연구)

  • Kim Chang Hyo;Choi Jin Sik
    • Korean journal of applied entomology
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    • v.15 no.1 s.26
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    • pp.7-16
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    • 1976
  • In order to increase utility efficiency of red wood ants, Formica rufa truncicola var. yessonesis Forel as a resource of natural enemy of pine caterpillar, Dendrolimus spectabilis Butler, by finding out ecological and environmental factors in the habitat of red wood ants, the nest distribution and its density in habitat, plant distribution and density, stand-density of red pine, nest building and fixing plants, relative humidity of surface soil, physical and chemical natures of soil, and breeding rate were examined. The obtained results are summarized as follows: 1. The nest of red wood ants was densely distributed, in the lower-and middle top of mountain but no nest was found in the top. 2. The economical distribution of nest of habitat was estimated as $2.85/m^2$ and the lowest density as $1.93/m^2$ and these estimation lead us to confirm that pine caterpillar could be controlled. 3. The ecological characteristics of habitat seemed to be represented as higher stand-density of red pine of 10-20 years of age with large areas of eroded land under trees. The major grasses prevailing in this area were Andropogon brevifolius. Arundinella hirta, Miscanthus purpurasens, Eulia speciosa, Themeda japonica, Cymbopogon goeringii, and Eccoilpus cotulifer 4. Red wood ants seemed to build the nest by using red pine, Arundinella hirta, Miscanthus purpurascens, Themeda japonica or Cymbopogon goeringii as a fixing plant. 5. The limited point of humidity percent in habitat of red wood ants was estimated as $76\%$ during the acting period of May to September and as $72\%$ during pre-period of hibernation of October to November. 6. Soil analysis in habitating region showed higher concentration of organic matters and lower concentration of calcium and magnesium, and habitat was largely composed of silt and fine sand rather than coarse sand. 7. When the separated colony was transplanted to non-habitating red pine forest that seemed to have the similiar conditions as those of habitat, propagation and establishment of nest was possible.

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An Analysis in Visitors' Attentions on Exhibit Panels of a Tesla Coil in the Gwacheon National Science Museum (국립과천과학관의 테슬라코일 전시물 설명판에 대한 관람객의 주목도 분석)

  • Lee, Il;Yoo, Jun-Hee;Chung, Kwang-Hoon
    • Journal of The Korean Association For Science Education
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    • v.32 no.1
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    • pp.46-63
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    • 2012
  • The purpose of this research is to explore factors which influence visitors' attention on exhibition panels by analyzing visitors' attention according to topic types and visitor group types. The subjects of this research are exhibition panels of a Tesla Coil exhibition in the Gwacheon National Science Museum. The exhibition panels' topic are basic concepts, explanations of phenomena, operating principles, applications and historical background. These topics are selected through a survey of visitors' intellectual needs for a Tesla Coil. Five new exhibition panels according to the topics are developed and visitor groups' behaviors in front of the panels are recoded in natural situations. The total participant groups are 586 groups, which includes individual student (30.0%), individual adult (20.6%), student group (28.2%), adult group(2.4%), and family group (18.8%). Visitors' attention to exhibition panels is sub-categorized into attracting power and holding power. Attracting power is defined by the percentile of group numbers who attend to an exhibition panel more than 3 seconds to the total group numbers who attend to an exhibition panel for more than a glance. Holding power is defined by average attention time and decay time. The attracting powers of historical background and application panels are 72.3% and 68.8% respectively, while that of the basic concept panel is 47%. Average attention times of explanation of phenomena and operating principle are 37.0 and 34.2 seconds, while those of historical background and application panels are 25.4 seconds. The decay times of each panel shows the same patterns of average attention times. Attracting powers of panels easy to approach and holding powers of panels with in-depth scientific concepts seems to be high. Attracting powers of the individual adult, family, and student group are 66.9%, 66.4% and 62.4% respectively, while the attracting power of the adult group and individual student are 57.1%, and 55.7%. Average attention times of the student group, family, adult groups are 34.0, 33.0, 31.6 seconds respectively, while that of individual student is 19.5 seconds. The decay times of each group shows the same patterns of average attention times. Both of attracting powers and average attention times of the student group and family group are high, while both of individual student are low. Tentatively, attracting powers of exhibition panels seems to be influenced more by topic types of panels, and holding power seems to be influenced more by group type. But these results are very limited and further studies are needed.

Comparison of School Nursing Phenomena at Elementary, Middle and High Schools by Applying ICNP (ICNP를 적용한 학교간호현상 및 특성과 초.중.고등학교의 학교간호현상 비교)

  • Kim, Young-Im;Wang, Myoung-Ja;Yang, Soon-Ok;Hyun, Hye-Jin;Park, Eun-Ok
    • Journal of the Korean Society of School Health
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    • v.17 no.1
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    • pp.1-12
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    • 2004
  • Purpose : this study purposed to investigate school nursing phenomena in Korea by applying ICNP, the international standard nursing classification system developed by ICN, and to compare school nursing phenomena at elementary, middle and high schools. Method : The subjects of this study are 110 nursing teachers from 82 elementary schools, 16 middle schools, and 12 high schools. In the survey, subjects were asked to score the degree to which phenomena and characteristics of Korean school nursing, identified in previous research, on a 5 point scale. Questionnaires were distributed and recovered by mail and email. The period of data collection was 6 months from July to December 2003. The general characteristics of schools and nursing teachers were represented with frequencies and percentages, the phenomena and characteristics of school nursing with the mean score of the questions, and the phenomena school nursing by school grade with ANOVA and Duncan's posterior analysis. Results : 1) As for the characteristics of schools according to school nursing phenomena related to human behavior, the mean score of questions on inadequate stress management was highest at 3.24 points followed by the score on inadequate weight control (3.23), inadequate eating habits (3.22), the risk of spine disorders (2.68), inadequate emergency management (2.62), inadequate response to sex -related problems (2.19), and smoking and drug use (1.85). 2) As for the characteristics of schools according to school nursing phenomena related to human function, the mean score of questions on oral health management was highest at 3.11 points followed by the score on the risk of digestive system disorder (2.87), improper eyesight management (2.81), the risk of respiratory system disorders (2.75), lack of sexual identity (2.52), and inadequate contagious disease control (2.12). 3) As for the mean score according to school nursing phenomena related to environment, the score of the risk of accidents in classroom was highest as 2.68 points followed by the score of the risk of accidents around the school (2.65), maladjustment to school (2.62), the risk of accidents outside the classroom (2.43), inadequate learning environment (1.83), the risk of exposure to socially and physically harmful environment factors (1.82), and inadequate waste disposal (1.77). 4) This study tested the mean scores of questions corresponding to each school nursing phenomenon in order to see if there is a difference in the school nursing phenomenon among elementary, middle and high schools, and performed Duncan's posterior comparison for school nursing phenomena. A significant difference was found at p<.1. According to the results, school nursing phenomena found to be significantly different among elementary, middle and high schools was smoking and drug use (p<.05), which appeared more problematic in high school than in elementary school. phenomena such as inadequate eating habits, inadequate weight control, inadequate response to sex-related problems and inadequate waste disposal were also found to be statistically different at p<.1; however, according to the result of Duncan's posterior comparison, no difference was found among groups in improper eating habits and improper response to sex-related problems, and a significant difference was found between middle and high schools in inadequate weight control and inadequate waste disposal. Conclusion: Based on the results of this study, it is necessary to plan school health projects focused on the characteristic school nursing phenomena that had high scores and to develop and execute school healthe projects in accordance with the characteristics of elementary, middle and high schools. Considering that the scores of school nursing phenomena related to human behavior are high, it is necessary to introduce school health promotion projects in a systematic way.

Factors Affecting Wet-Paddy Threshing Performance (탈곡기의 제작동요인이 벼의생탈곡성능에 미치는 영향)

  • 남상일;정창주;류관희
    • Journal of Biosystems Engineering
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    • v.5 no.1
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    • pp.1-14
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    • 1980
  • Threshing operation may be one of the most important processes in the paddy post-production system as far as the grain loss and labor requirement are concerned . head-feeding type threshers commercially available now in Korea originally were developed for threshing dry paddy in the range of 15 to 17 % in wet basis. However, threshing wet-paddy with the grain moisture content above 20 % has been strongly recommended, especially for new high-yielding Indica -type varieties ; (1) to reduce high grain loss incurred due to the handling operations, and (2) to prevent the quantitative and qualitative loss of milled -rice when unthreshed grains are rewetted due to the rainfall. The objective of this study were to investigate the adaptability of both a head-feeding type thresher and a throw-in type thresher to wet-paddy , and to find out the possiblilities of improving the components of these threshers threshing. Four varieties, Suweon 264 and Milyang 24 as Tongil sister line varieties, minehikari and Jinhueng as Japonica-type varieties, were used at the different levels of the moisture content of grains. Both the feed rate and the cylinder speed were varied for each material and each machine. The thresher output quality , composition of tailing return, and separating loss were analyzed from the sampels taken at each treatment. A separate experiment for measurement opf the power requirement of the head-feeding type thresher was also performed. The results are summarized as follows : 1. There was a difference in the thresher output quality between rice varieties. In case of wet-paddy threshing at 550 rpm , grains with branchlet and torn heads for the Suweon 264 were 12 % and 7 % of the total output in weight, respectively, and for the Minehikari 4.5 % and 2 % respectively. In case of dry paddy threshing , those for the Suweon 264 were 8 % and 5% , and for the Minehikari 4% and 1% respectively. However, those for the Milyang 23 , which is highly susceptable to shattering, were much lower with 1 % and 0.5% respectively, regardless of the moisture content of the paddy. Therefore, it is desirable to breed rice varieties of the same physical properties as well as to improve a thresher adaptable to all the varieties. Torn heads, which increased with the moisture content of rall the varieties except the Milyang 23 , decreased as the cylinder speed increased, but grains with branchlet didnt decrease. The damaged kernels increased with the cylinder speed. 3. The thresher output quality was not affected much by the feed rate. But grains with branchlet and torn heads increased slightly with the feed rate for the head-feeding type thresher since higher resistance lowered at the cylinder speed. 4. In order to reduce grains with branchlet and torn heads in wet-paddy threshing , it is desirable to improve the head-feeding type thresher by developing a new type of cylinder which to not give excess impact on kernels or a concave which has differenct sizes of holes at different locations along the cylinder. 5. For the head-feeding type thresher, there was a difference in separating loss between the varieties. At the cylinder speed of 600 rpm the separating losses for the Minehikari and the Suweon 264 were 1.2% and 0.6% respectively. The separating loss of the head-feeding type thresher was not affected by the moisture content of paddy while that of the Mini-aged thresher increased with the moisture content. 6. From the analysis of the tailings return , to appeared that the tailings return mechanism didn't function properly because lots of single grains and rubbishes were unnecessarily returned. 7. Adding a vibrating sieve to the head-feeding type thresher could increase the efficiency of separation. Consequently , the tailing return mechanism would function properly since unnecessary return could be educed greatly. 8. The power required for the head-feeding type thresher was not affected by the moisture content of paddy, but the average power increased linearly with the feed rate. The power also increased with the cylinder speed.

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The Analysis and Treatment of Rotator Cuff Tear After Shoulder Dislocation in Middle-Aged and Elderly Patients (중·장년층에서 견관절 탈구 후에 발생한 회전근 개 파열에 대한 분석과 치료)

  • Ji, Jong-Hun;Park, Sang-Eun;Kim, Young-Yul;Shin, Eun-Su;Park, Bo-Youn;Jeong, Jae-Jung
    • Clinics in Shoulder and Elbow
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    • v.13 no.1
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    • pp.20-26
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    • 2010
  • Purpose: To evaluate clinical features and surgical results for rotator cuff tear secondary to shoulder dislocation in middle-aged and elderly patients. Materials and Methods: We reviewed 19 patients over 50 years of age who had rotator cuff tears combined with shoulder dislocation between October 2004 and October 2008. There were 7 males and 12 females with a mean age 64.7 years (range, 50 to 78 years). The average follow-up duration was 22 months (range, 8 to 56 months). We investigated the number of dislocations, the size of the cuff tear, the presence of Bankart lesions and the time interval from dislocation to surgery. We also investigated the ASES score, UCLA score, SST score, and shoulder range of motion before and after surgery. We analyzed clinical outcomes and contributing factors. Results: ASES scores improved from 30.2 preoperatively to 72.3 postoperatively; UCLA scores improved from 12.9 to 26.5; SST scores improved from 2.4 to 7.3. Range of motion improved significantly: forward flexion, abduction, external rotation and internal rotation were, respectively, $110.8({\pm}39.3)^{\circ}$, $107.7({\pm}40)^{\circ}$, $22.5({\pm}17.6)^{\circ}$ and L5 level preoperatively; postoperatively they were $153.6({\pm}20.6)^{\circ}$, $152.1({\pm}20.8)^{\circ}$, $36.4({\pm}22.7)^{\circ}$ and L1 level. Age, the presence of Bankart lesions and the number of dislocations were not correlated with clinical outcomes. But the size of the cuff tear was correlated with clinical results. Also, the duration from dislocation to surgery was correlated with postoperative UCLA and SST scores (p=0.039, p=0.038). Conclusion: For shoulder dislocation, it is important to achieve early diagnoses of rotator cuff tears in middle-aged and elderly patients. If these injuries are both present, early rotator cuff repair should be performed for better clinical results.

The Accuracy Evaluation according to Dose Delivery Interruption and Restart for Volumetric Modulated Arc Therapy (용적변조회전 방사선치료에서 선량전달의 중단 및 재시작에 따른 정확성 평가)

  • Lee, Dong Hyung;Bae, Sun Myung;Kwak, Jung Won;Kang, Tae Young;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.25 no.1
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    • pp.77-85
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    • 2013
  • Purpose: The accurate movement of gantry rotation, collimator and correct application of dose rate are very important to approach the successful performance of Volumetric Modulated Arc Therapy (VMAT), because it is tightly interlocked with a complex treatment plan. The interruption and restart of dose delivery, however, are able to occur on treatment by various factors of a treatment machine and treatment plan. If unexpected problems of a treat machine or a patient interrupt the VMAT, the movement of treatment machine for delivering the remaining dose will be restarted at the start point. In this investigation, We would like to know the effect of interruptions and restart regarding dose delivery at VMAT. Materials and Methods: Treatment plans of 10 patients who had been treated at our center were used to measure and compare the dose distribution of each VMAT after converting to a form of digital image and communications in Medicine (DICOM) with treatment planning system (Eclipse V 10.0, Varian, USA). We selected the 6 MV photon energy of Trilogy (Varian, USA) and used OmniPro I'mRT system (V 1.7b, IBA dosimetry, Germany) to analyze the data that were acquired through this measurement with two types of interruptions four times for each case. The door interlock and the beam-off were used to stop and then to restart the dose delivery of VMAT. The gamma index in OmniPro I'mRT system and T-test in Microsoft Excel 2007 were used to evaluate the result of this investigation. Results: The deviations of average gamma index in cases with door interlock, beam-off and without interruption on VMAT are 0.141, 0.128 and 0.1. The standard deviations of acquired gamma values are 0.099, 0.091, 0.071 and The maximum gamma value in each case is 0.413, 0.379, 0.286, respectively. This analysis has a 95-percent confidence level and the P-value of T-test is under 0.05. Gamma pass rate (3%, 3 mm) is acceptable in all of measurements. Conclusion: As a result, We could make sure that the interruption of this investgation are not enough to seriously affect dose delivery of VMAT by analyzing the measured data. But this investigation did not reflect all cases about interruptions and errors regarding the movement of a gantry rotation, collimator and patient So, We should continuously maintain a treatment machine and program to deliver the accurate dose when we perform the VMAT for the many kinds of cancer patients.

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Analyses of Elementary School Homeroom Teachers' Role Percept ion and Performance as Counsellors and Children's Expectation for Teachers' Role as Counsellors (초등학교 담임교사의 상담자로서 역할지각 및 수행실태와 아동의 기대 분석)

  • Seo, Ju-Hee;Kim, Yang-Hyun
    • The Korean Journal of Elementary Counseling
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    • v.5 no.1
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    • pp.65-92
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    • 2006
  • The objective of this study is to conduct survey analyses of the role perception and performance of homeroom teachers in elementary schools in Seoul as well as their students' expectations for teachers' role as counsellors. The study also aims to analyze the causes behind the lackluster performance, to provide assistance in teachers' counselling and guidance activities and collect basic data for providing a plausible orientation for elementary school counselling. Research topics for achieving these study objectives are as follows. First, what is the status quo of counselling between elementary school students and teachers? Second, what is the role perception of elementary school homeroom teachers as counsellors and their current level of performance? Third, what are the differences in students' expectations for homeroom teachers' role as counsellors according to students' environmental variables such as gender and grade? Fourth, what are the discrepancies between the roles perception and performance of elementary school homeroom teachers and role expectation of students for homeroom teachers' role as counsellors? In order to answer these questions, surveys were conducted for 229 teachers and 385 students in grades 4, 5 and 6 in 11 elementary schools in Seoul, and the results were analyzed. The questionnaires used for this study were modified and supplemented according to the research objectives based on survey questions released by Gyung-Beom Lee(1989), Hak-Soo Lee(2001) and Gi-Nam Gwon(2005). Statistical analyses were peformed using the SPSS for Windows 10.0 program. The results of the study can be summarized as follows. First, most elementary school homeroom teachers were involved in counselling activities, and about half of them were providing counselling once a month or less. The classroom was the primary location of counselling, and more than half of the surveyed teachers were dissatisfied with their counselling activities. The teachers cited overwhelming teaching hours and excessive work as the factors that made counselling difficult. Second, it was revealed that most elementary school students have had experiences of anguish and most have had some form of counselling. They mostly sought counselling from their parents and friends, and the reasons behind such choices were that they were very understanding. Third, most students responded that they have had no experience of receiving counselling from their homeroom teachers. Among those with counselling experience with their homeroom teachers, most said that the counselling was helpful. The most significant reason for not receiving counselling from their homeroom teachers was that the students had no worries to talk about with their teachers. Fourth, as a result of categorizing the role of elementary school homeroom teachers as counsellors according to the areas of counselling, role perception for each area turned out to be generally high, while performance was substantially lacking. Fifth, in terms of the causes for the lackluster counselling performance, overwhelming teaching hours and excessive work were indicated for counselling areas of academic and personality issues. Sixth, the analysis of students' expectations for elementary school homeroom teachers as counsellors for counselling areas according to gender and grade revealed that there was no overall statistical significance. Seventh, from the general perspective, the level of role perception of the homeroom teachers were higher than the level of students' expectations. In conclusion, in order to enhance the teacher's role as a counsellor, there has to be a concrete perception of roles as a primary premise, calling for training sessions and programs dedicated to counseling for the teachers to take part in. Moreover, in order to alleviate the most significant causes for undermining teachers' counselling activities - overwhelming teaching hours and excessive work - there must be administrative consideration as well as provisions for effective counselling centers and dedicated school counsellors.

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The Effects of rhBMP-2/ACS on the Periodontal Healing of 1-Wall Intrabony Defects in Dogs (성견 1면 골결손부에서 rhBMP-2/ACS가 치주조직 치유에 미치는 영향)

  • Jun, Hye-Young;Cho, Kyoo-Sung;Kim, Chong-Kwan;Chai, Jung-Kiu
    • Journal of Periodontal and Implant Science
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    • v.29 no.4
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    • pp.873-893
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    • 1999
  • The ultimate goal of periodontal therapy is the regeneration of periodontal tissue and repair of function. For more than a decade there have been many efforts to develop materials and bioactive molecule(such as growth factor and differentiation factors) to promote periodontal wound healing. Among the bioactive molecules, bone morphogenetic protein(BMP) was studied for periodontal wound healing. Since Urist demonstrated that demineralized bone matrix could induce the formation of cartilage and bone in ectopic site, many studies on BMP have been reported. Among those BMPs, it was reported that rhBMP-2 enhanced the healing of bone defects in animal studies and clinical studies. However, its efficacy in periodontal regeneration, especially 1-wall intrabony defects is still unknown. The purpose of this study was to examine the effect of rhBMP-2/ACS on the epithelial migration, gingival connective tissue adhesion, cementum formation, alveolar bone regeneration in intrabony defects of dogs. Four millimeter deep and four millimeter wide 1-wall defects were surgically created in the mesial aspects of the 3rd incisors. The test group received rhBMP-2/ACS with a flap procedure and the control underwent buffer/ACS with a flap procedure. Histologic analysis after 8 weeks of healing revealed the following results: 1. The length of epithelial growth(the distance from alveolar crest to the apical end of JE) was $0.9{\pm}1.5mm$ in the control group and $1.2{\pm}1.4mm$ in the test group. There was no statistically significant difference between the two groups. 2. The length of connective tissue adhesion was $2.4{\pm}1.3mm$ in the control group and $1.2{\pm}1.1mm$ in the test group. The control group showed significantly enhanced adhesion(P<0.05). 3. The length of new cementum was $0.9{\pm}1.0mm$ in the control group and $1.7{\pm}0.8mm$ in the test group. The test group showed significantly enhanced cementum regeneration(P<0.05). 4. The length of new bone height was $1.9{\pm}0.6mm$ in the control group and $2.4{\pm}0.9mm$ in the test group. There was no statistically significant difference between the two groups. 5. The new bone area was $4.7{\pm}1.7mm^2$ in the control group and $8.0{\pm}2.0mm^2$ in the test group. The test group showed significantly enhanced bone formed area(P<0.05). 6. The new bone density was $73.0{\pm}8.6%$ in the control group and $66.6{\pm}15.3%$ in the test group. There was no statistically significant difference between the two groups. These results suggest that the use of rhBMP-2 in 1-wall intrabony defects has significant effect on new cementum and new bone formation area, but doesn't have any significant effect on the prevention of junctional epithelium migration and new bone formation height.

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