• Title/Summary/Keyword: 비이용자

Search Result 4,712, Processing Time 0.038 seconds

The effect of early loading on the direct bone-to-implant surface contact of the orthodontic osseointegrated titanium implant (교정력이 골유착성 티타니움 임프란트의 초기 고정에 미치는 영향에 관한 실험적 연구)

  • Chung, Kyu-Rhim;Lee, Sung-Ja
    • The korean journal of orthodontics
    • /
    • v.31 no.2 s.85
    • /
    • pp.173-185
    • /
    • 2001
  • The orthodontic osseointegrated titanium implant, a kind of intraoral skeletal anchorage can be an alternative to tooth-borne anchorage, in case that the conventional tooth-borne anchorage is not available or the anchorage is critical. This study was conducted to elucidate the effect of early loading on the osseointegration of the orthodontic titanium implant and the healing process of the impaired bone at the site of implant after removing it. In two adult beagle dogs24 osseointegrated titanium implants were inserted into the alveolar bone, with 12 implants placed in each dog. In dog1, 6 out of 12 implants were loaded with 200-300gm of force immediately after placing, and the remaining 6 implants were not loaded for 4weeks. In dog2, all 12 implants had healing period of 4weeks, and then were loaded with 200-300gm of force for another 4weeks. Following an observation period of 4 and 8 weeks, the animals were sacrificed. Then the implants and the surrounding bone of dog1 and dog2 were removed, respectively. Undecalcified sections along the long axis of implant were made and the degree of osseointegration was examined under the light microscope. The results were as follows. 1. In the histologic features of tissues around implants anchored in dog1, there was no difference between immediately loaded implants and unloaded implants. Immature woven bone was ingrowing into the thread spaces from the original compacta and in direct contact with the implant surface in part. 2. The premature loading just after 4weeks healing period did not halt the progress of the osseointegration between bone and implant surface. The woven bone around the implants was maturing into the lamellar bone which resembled the structure of the original compacta at the end of 8weeks observation period. 3. Most implants with the inflammed surrounding mucosa were lost or mobile. The mobile implants were encapsulated by fibrous connective tissue which separated the implant surface from the bone. 4. The impaired bone at the site of the implant failed to anchor was showing recovery without inflammatory reaction 2weeks after removing, with the immaure woven bone lined by active osteoblasts and osteoid. Based on the results of this study, the integration of this orthodontic implant seemed to be impaired by the inflammation of the tissue surrounding the Implant rather than by early loading on implant, and increased with time lapsed after placing the implant. The use of implant described in this report can be recommended as an orthodontic anchorage unit immediately after insertion under the careful control of orthodontic force applied and plaque.

  • PDF

Spatial Distribution Patterns and Prediction of Hotspot Area for Endangered Herpetofauna Species in Korea (국내 멸종위기양서·파충류의 공간적 분포형태와 주요 분포지역 예측에 대한 연구)

  • Do, Min Seock;Lee, Jin-Won;Jang, Hoan-Jin;Kim, Dae-In;Park, Jinwoo;Yoo, Jeong-Chil
    • Korean Journal of Environment and Ecology
    • /
    • v.31 no.4
    • /
    • pp.381-396
    • /
    • 2017
  • Understanding species distribution plays an important role in conservation as well as evolutionary biology. In this study, we applied a species distribution model to predict hotspot areas and habitat characteristics for endangered herpetofauna species in South Korea: the Korean Crevice Salamander (Karsenia koreana), Suweon-tree frog (Hyla suweonensis), Gold-spotted pond frog (Pelophylax chosenicus), Narrow-mouthed toad (Kaloula borealis), Korean ratsnake (Elaphe schrenckii), Mongolian racerunner (Eremias argus), Reeve's turtle (Mauremys reevesii) and Soft-shelled turtle (Pelodiscus sinensis). The Kori salamander (Hynobius yangi) and Black-headed snake (Sibynophis chinensis) were excluded from the analysis due to insufficient sample size. The results showed that the altitude was the most important environmental variable for their distribution, and the altitude at which these species were distributed correlated with the climate of that region. The predicted distribution area derived from the species distribution modelling adequately reflected the observation site used in this study as well as those reported in preceding studies. The average AUC value of the eigh species was relatively high ($0.845{\pm}0.08$), while the average omission rate value was relatively low ($0.087{\pm}0.01$). Therefore, the species overlaying model created for the endangered species is considered successful. When merging the distribution models, it was shown that five species shared their habitats in the coastal areas of Gyeonggi-do and Chungcheongnam-do, which are the western regions of the Korean Peninsula. Therefore, we suggest that protection should be a high priority in these area, and our overall results may serve as essential and fundamental data for the conservation of endangered amphibian and reptiles in Korea.

Impact of Elevated Temperature in Growing Season on Growth and Fruit Quality of Red Pepper (Capsicum annuum L.) (생육기 온도상승이 고추의 생육 및 과실품질에 미치는 영향)

  • Song, Eun Young;Moon, Kyung Hwan;Son, In Chang;Kim, Chun Hwan;Lim, Chan Kyu;Son, Daniel;Oh, Soonja
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.16 no.4
    • /
    • pp.349-358
    • /
    • 2014
  • This study was conducted to determine the impact of elevated temperature in growing season on the growth and fruit quality of red pepper (Capsicum annuum L.) by cultivating pepper in the temperature gradient tunnels. Plant height, stem diameter, leaf number and total leaf area, fresh weight and dry weight increased at ambient $+2^{\circ}C$ temperature, whereas each leaf area decreased as temperature increased. The plants grown under ambient $+2^{\circ}C$ temperature showed the greatest number of flower and fruit. Fruit weight, fruit length and fruit diameter decreased as the temperature increasing gradually. Total fruit number, total fruit weight and total dry fruit weight was the highest at ambient $+2^{\circ}C$ temperature. Major free sugars of red pepper fruit were fructose and glucose. Free sugar content of red pepper according to the differences in harvesting times and in growth temperature showed a little differences. The yield of red pepper fruit at ambient $+2^{\circ}C$ temperature increased by 13% compared with the control. However, the yield of red pepper fruit at ambient $+4^{\circ}C$ temperature decreased by 20% as compared to control. Non-marketable fruits (diseased fruit, malformed fruit and small sized fruit) increased as the temperature rised.

Association between Genotypes of the Isocitrate Dehydrogenase 3, beta subunit (IDH3B) Gene and Carcass Traits in an F2 Crossbred Population of Landrace × Jeju (Korea) Black Pigs (제주흑돼지와 랜드레이스 교배 2세대의 도체형질과 IDH3B 유전자형의 상관관계)

  • Kang, Yong-Jun;Jeong, Dong Kee;Cho, In-Cheol;Han, Sang-Hyun
    • Journal of Life Science
    • /
    • v.26 no.4
    • /
    • pp.414-418
    • /
    • 2016
  • This study tested the association between genetic polymorphisms of the isocitrate dehydrogenase 3, beta subunit (IDH3B) gene and economic traits in an F2 crossbred population of Landrace × Jeju (South Korea) Black pigs. A 304-bp insertion/deletion mutation in promoter region was screened for determining genotypes of the IDH3B gene in a total of 1,105 F2 pigs. Three genotypes (AA, AB, and BB) were identified in the founder, F1, and F2 populations. Association analysis showed significant differences in carcass weights (CW), backfat thicknesses in three positions of the body (4th-5th ribs, BF5; 11th-12th ribs, BF12; 13th rib-1st lumbar, BFL), and carcass lengths (CL) (p<0.05), but not in meat color (MC), eye muscle area (EMA), or marbling scores (MARB) (p>0.05). The F2 IDH3B BB homozygotes showed heavier CW (80.790±0.725 kg) and shorter CL (101.875±0.336 cm) than the other genotypes (p<0.05). In addition, the BF levels between the 4th - 5th and 11th - 12th vertebrae were thicker in the carcasses of pigs with the IDH3B BB genotype than with the other genotypes (p<0.05). These results suggested that genetic variations in the IDH3B gene may serve as molecular genetic markers for improving the Landrace × Jeju Black pig crossbreeding systems.

A Study on the Recognition and Requirement of Dental Hygienists for Academic Credit Bank System (치과위생사들의 학점은행제에 대한 인식 및 요구)

  • Jang, Young-Ho;Choi, Mi-Sook;Kim, Eun-Hee;Yang, Seung-Kyeong
    • Journal of dental hygiene science
    • /
    • v.7 no.4
    • /
    • pp.287-293
    • /
    • 2007
  • As a result of having surveyed and analyzed recognition and requirement of dental hygienists for Academic Credit Bank System, the recognition on Academic Credit Bank System accounted for 70.8%, and in terms of information media recognized, surrounding people were the highest with 52.4%. And, in case of the response as saying of being willing to participate, an opportunity of acquiring a bachelor's degree accounted for 24.0%, and in case of the response as saying of being unwilling to participate, the lack of time that will take part in education activity accounted for 13.7%, thereby having been surveyed to be the most preferential choice, respectively. The importance by sphere in course programs was indicated to be the sphere of preventive dental treatment with 3.61, the sphere of dental management with 3.38, the sphere of oral health education with 3.09, the sphere of medical-treatment coordination with 2.82, and the sphere of community dental health with 2.11 in order. The importance by field of sphere in course programs was indicated to be high in the field of oral health education by subject with 2.30 for the field of sphere in oral health education, in the field of plaque control and oral prophylaxis with 3.53 for the field of sphere in preventive dental treatment, in the field of management of the fluoride mouth-rinsing programme with 2.86 for the field of sphere in community dental health, in the field of counselling with 3.24 for the field of sphere in dental management, and in the field of medical-treatment assistance with 1.53 for the field of sphere in medical-treatment coordination.

  • PDF

The Antimicrobial Effect of Water Soluble Chitosan (수용성 키토산의 항균효과)

  • Jung, Byung-Ok;Lee, Young-Moo;Kim, Jae-Jin;Choi, Young-Ju;Jung, Kyung-Ja;Kim, Je-Jung;Chung, Suk-Jin
    • Applied Chemistry for Engineering
    • /
    • v.10 no.5
    • /
    • pp.660-665
    • /
    • 1999
  • Structure of water soluble chitosan (WSC) was confirmed by Fourier transform infrared spectrometer (FT-IR), X-ray diffractometer and thermal analyser. The viscosity average molecular weight of WSC ranged from $3.0{\times}10^{4}$ to $4.5{\times}10^{4}$. Using the WSC having viscosity average molecular weight of $3.0{\times}10^{4}$, the antimicrobacterial effects against microorganism and oral microorganism showed 81.7% and 80.6% for Staphyloccus aureus and Bacillus subtilis, respectively, while the anitmicrobacterial effect exhibited 100% and 73.8% against Streptococcus mutans and Streptococcus sanguis, respectively. Therefore it is concluded that WSC is more effective against oral microorganism that microorganism in terms of antimicrobacterial effects. WSC sample with the viscosity average molecular weight of $4.5{\times}10^{4}$ exhibited a half of the antimicrobacterial effect of the low MW sample, indicating that the WSC with low MW was better than that with high MW. Chitin and chitosan showed a drastic decrease of acidity from pH 7.0 to 4.9 after 8 minute incubation time and reached an equilibrium after that. WSC, however, restrained pH of the sample from lowering up to about 16 minutes of incubation and reached an equilibrium after that. WSC obviously showed a buffering effect against pH change.

  • PDF

Improvement of analytical methods for arsenic in soil using ICP-AES (ICP-AES를 이용한 토양 시료 중 비소 분석 방법 개선)

  • Lee, Hong-gil;Kim, Ji In;Kim, Rog-young;Ko, Hyungwook;Kim, Tae Seung;Yoon, Jeong Ki
    • Analytical Science and Technology
    • /
    • v.28 no.6
    • /
    • pp.409-416
    • /
    • 2015
  • ICP-AES has been used in many laboratories due to the advantages of wide calibration range and multi-element analysis, but it may give erroneous results and suffer from spectral interference due to the large number of emission lines associated with each element. In this study, certified reference materials (CRMs) and field samples were analyzed by ICP-AES and HG-AAS according to the official Korean testing method for soil pollution to investigate analytical problems. The applicability of HG-ICP-AES was also tested as an alternative method. HG-AAS showed good accuracies (90.8~106.3%) in all CRMs, while ICP-AES deviated from the desired range in CRMs with low arsenic and high Fe/Al. The accuracy in CRM030 was estimated as below 39% at the wavelength of 193.696 nm by ICP-AES. Significant partial overlaps and sloping background interferences were observed near to 193.696 nm with the presence of 50 mg/L Fe and Al. Most CRMs were quantified with few or no interferences of Fe and Al at 188.980 nm. ICP-AES properly assessed low and high level arsenic for field samples, at 188.980 nm and 193.696 nm, respectively. The importance of the choice of measurement wavelengths corresponding to relative arsenic level should be noted. Because interferences were affected by the sample matrix, operation conditions and instrument figures, the analysts were required to consider spectral interferences and compare the analytical performance of the recommended wavelengths. HG-ICP-AES was evaluated as a suitable alternative method for ICP-AES due to improvement of the detection limit, wide calibration ranges, and reduced spectral interferences by HG.

Study of the Tone Variation on Juniperus chinensis L. and Populus glandulosa Uyeki by Photographs (사진상(寫眞上)에 나타난 향나무(Juniperus chinensis L.)와 수원사시나무(Populus glandulosa Uyeki)의 색조변화(色調變化)에 관(關)한 연구(硏究))

  • Kim, Kap Duk
    • Journal of Korean Society of Forest Science
    • /
    • v.13 no.1
    • /
    • pp.1-24
    • /
    • 1971
  • In order to elucidate the feasibility to identify the plant species through the photographic tone this study was made. In this study the author made photographs of Juniperus chinensis L., and Populus glandulosa Uyeki, with the panchromatic film using either yellow filter or red filter in different seasons respectively. The author analyzed the value of tone variation at the level of stereoscopic view of the same photographs by using tone scale and Automatic Micro-Photo-Densitometer. The results obtained are summarized as follows: A. Tone scale reading 1. The tone of Populus glandulosa Uyeki was darker than that of Juniperus chinensis L. in a photograph. 2. Regardless of the tree species, tone of photographs obtained with yellow filter was darker than that with red filter. 3. Along the progresses of seasons, the photographic tone was changed. That is, from the spring to the summer it showed darker and than, from the summer to winter it changed lighter. 4. During winter and spring the discrimination between the both species of trees can be easily made by stereoscopic view whether there are leaves on the tree or not rather than by tone observation. 5. Regardless of tree species, variation of tone due to the age was noticed. The older trees have darker tone than the younger one. 6. It is recognized that the yearly difference depends on insolation quantities. 7. The highest reflex light-waves were in between $600m{\mu}$ and $660m{\mu}$ for both species of trees. B. Density reading 1. For the density reading, there was the same tendency as in tone scale reading. 2. The changes of peaks of the scanning curves with Populus glandulosa Uyeki is smoother and takes place in lower position than with Juniperus chinensis L. 3. The scanning curves on the 20th May was smoothest, and change of peaks increased gradually according to the season progresses. 4. In relation to the types of filter the photographs with yellow filter showed less changes of peaks then that with red filter.

  • PDF

A study for Developing Performance Assessment Model of Technology Entrepreneurship Education Based on BSC - A Case Study to Graduate School of Entrepreneurial Management - (BSC(Balanced Scorecard) 기반의 기술창업교육 성과평가모형 개발 연구 - 창업대학원 성과평가지표 분석과 개선방안도출을 중심으로 -)

  • Yang, Young Seok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.8 no.2
    • /
    • pp.129-139
    • /
    • 2013
  • This paper is targeted on proposing ameliorating alternative to performance assessment method of GSEM through evaluating the current one, which is initiated by SMBA to induce fair competition among 5 GSEM across the country and accommodate the quality improvement of entrepreneurship education since 2005 after beginning the SMBA support, from the perspective of BSC(Balanced Scorecard) tool. Ultimately, it complements the policy defects of SMBA over GSEM, in particular, in the process of performance assessment and management. This paper carries out two studies as follow. First, throughout reviewing the previous studies relating to BSC applications to non-profit organization, it set out the direction of introducing BSC in assessing performance of GSEM in order to enhance its effectiveness. Second, it evaluate the rationality of performance assessing tools apllied to GSEM by SMBA on the basis of BSC application over non-profit organization, especially in education institution. Research results shows the following implications. First, the current evaluation system over GSEM is just merely assessment itself and not much contributions for the post performance management. Second, The annual evaluation just remains to check up whether the policy goals are met or not. Third, the current evaluation puts much emphasis just on financial inputs and hardware infra, not considering human resources and utilization of government policy and institution. Fourth, the policy goals are unilaterally focused on entrepreneurs. Fifth, the current evaluation systems do not contain any indexes relating to learning and growth perspectives for concerning sustainable and independent growing up. However, lack of empirical testing require this paper to need the further study in the future.

  • PDF

The Synthesis and MR Properties of New Macromolecular MR Contrast Agent (새로운 거대분자 MR 조영제의 합성 및 MR 특성에 관한 연구)

  • 장용민;장영환;황문정;박현정;전경녀;이종민;배경수;강봉석
    • Investigative Magnetic Resonance Imaging
    • /
    • v.6 no.1
    • /
    • pp.35-40
    • /
    • 2002
  • Purpose : To evaluate the NMR relaxation properties and imaging characteristics of tissue-specificity for a newly developed macromolecular MR agent. Materials and methods : Phthalocyanine (PC) was chelated with paramagnetic ion, Mn.2.01g (5.2 mmol) of Phthalocyanine was mixed with 0.37g (1.4 mmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography (CHC13/CH3OH 98/2 v/v, Rf, 0.76) to obtain 1.04g (46%) of MnPC (molecular weight= 2000d). The $T1}T2$ relaxivity of MnPC was measured in 1.5T(64 MHz) MR using 0.1 mM MnPC. The MR image characteristics of MnPC was evaluated using spin-echo (TR/TE=500/14 msec) and gradient-echo (FLASH) (TR/TE=80/4 msec, flip angle=60) techniques in 1.57 MR scanner. The images of rabbit liver were obtained every 10 minutes up to 4 hours. To study the effect of concentration on image, 20 mM, 50 mM, 100 mM of MnPC were tested. Results : The relaxivities of MnPC at 1.5T(64MHz) were Rl=7.28 $mM^{-1}S^{-1},{\;}R2=55.56mM^{-1}S^{-1}$. Compared to the values of Gd-DTPA (Rl[=4.8 $mM^{-1}S^{-1})$], R2[=5.2 $mM^{-1}S^{-1}])$]), both T1/T2 relaxivities of MnPC were higher than those of Gd-DTPA. For both of SE and FLASH techniques, the contrast enhancement reached maximum at 10 minutes after bolus injection and the enhancement continued for more than 2 hours. When compared with small molecular weight liver agents such as Gd-EOB-DTPA, Gd-BOPTA and MnDPDP, MnPC was characterized by more prolonged enhancement time. The time course of MR images also revealed biliary excretion of MnPC. Conclusion : We developed a new macromolecular MR agent, MnPC. The relaxivities of MnPC were higher than those of small molecular weight Gd-chelate. Hepatic uptake and biliary excretion of MnPC suggests that this agent is a new liver-specific MR agent.

  • PDF