• 대한치과보철학회지
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• 제41권5호
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• pp.582-595
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• 2003

Statement of problem : Most posts are metallic, but in response to the need for a post that possesses optical properties compatible with an all-ceramic crown. an esthetic post has been developed. Although there have been many studies about the esthetic post materials, 3-dimensional finite element studies about the stress distribution of them are in rare. Purpose : The purpose of this study is to investigate comparatively the distribution of stresses of the restored, endodontically treated maxillary incisors with the esthetic post materials and the displacement on the cement layer on simulated occlusal loading by using a 3-dimensional finite element analysis model. Material and method : Four 3-dimensional finite element models were constructed in a view of a maxillary central incisor, a post, a core, and the supporting tissues to investigate the stresses in various esthetic posts and cores and the displacement on the cement layer (Model 1 ; Cast gold post and core, Model 2 ; Glass fiber post with composite core, Model 3 ; Zirconia post with composite core. Model 4 ; Zirconia post with ceramic core). Force of 300N was applied to the incisal edge and the cingulum (centric stop point) with the angle of 135-degree to the long axis of the tooth. Results : 1. The stresses and displacement on the incisal edge were higher than on the cingulum 2. The stresses in dentin were the highest in Model 2 (Glass fiber post with composite core), and the second was Model 3, the third Model 1, and the lowest Model 4. 3. The stresses in post and core were the highest in Model 4 (Zirconia post with ceramic core), and the second was Model 1, the third Model 3, and the lowest Model 2. 4. The displacement on the cement layer was the highest in Model 2 (Glass fiber post with composite core), and the second was Model 3, the third Model 1, and the lowest Model 4. Conclusion : When a functional maximum bite force was applied, the distribution of stresses or the esthetic post and core materials and the displacement on the cement layer were a little different. It seems that restoring extensively damaged incisors with esthetic post and core materials would be decided according to the remaining tooth structure.

• 여성건강간호학회지
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• 제5권2호
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• pp.222-229
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• 1999

These days, as the society has been in the trends of highly industrialized and the family has been downsized, there is remarkably increasing number of women who follow occupation. These changes have made it more difficult for the family to help post-partum mother, which had been performed in side of house. By the help of social believe that during at least 1 month after childbirth professional nursing program is indispensable for both maternity protection and physical-mental recuperation, now many post-partum care centers for post-partum mother have been in operation. Although these post-partum care center have in use for a long time, no study was performed before this study on the same subject. Data were analyzed using by SAS. The results of study are as follow : 1. The general features of the user of the post-partum care center. The predominant band of user's age is extended from 26 to 30. The users are mainly housewives and they are in higher level of incomes and educations. As for the feature of delivery methods, they performed the normal spontaneous vaginal delivery method by 58.0% and the Caesarean operation method by 42.0%. As for the sexuality for babies, 59.3% of infants are male, and 40.7% are female. The highest delivery order of users is first and admission after 1-3days delivery is highest. 2. The results for the investigation into the actual condition of the post-partum care center are as follow : About the main reason for entrance of the post-partum care center was found to be the needs for the better nursing programs for recuperation after childbirth. This demands are also supported by their husbands. The average length of stay in the post-partum care center is 17.6 days and the besides promised expense ; powdered milk, milk-suckers, disposable dippers, skin cares, body shape cares, entrophics, injections. The post-partum have private rooms for mother and infants. Over the half of average expense is 229 million won. They are paying accessory fees the post-partum care center have similar step organization : the nurses, the skin carers, the cleaners. Mostly both ways of feeding powdered milk and breast feeding are in use, and mother's milk is preserved in the night time to be given to infant by nurse in charge. 3. The results of the investigation on users' nursing demand to the post-partum care center and satisfaction are as follow : The ranking order of nursing demand of mothers who used the is that ; infant care demands, environmental demands, emotional and mental care demands, education and training demands. As much as 70% of the respondents have dissatisfaction in nursing program, The ranking order of service satisfaction of mothers who used appears to be higher following order ; satisfaction in infant care demand, satisfaction in physical nursing demand, satisfaction in emotional and mental nursing demand, satisfaction in education and training demand, satisfaction in environment nursing demand. The results of pearson correlation. between nursing demand and service satisfaction of mothers who used are found to be relative noticeable in the level of 0.05. only infant care. The 61.7% of the women who used the post-partum care center. are responding that they will reuse the same post-partum care center again.

• 한국동물위생학회지
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• 제18권3호
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• pp.1-12
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• 1995

To investigate effect of seeding on post-thaw motility and viability of canine spermatozoa, the semen from male dogs which had been proved to be fertile in the past were frozen and seeded during freezing process. Post-thaw motility and viability of canine sperm which were frozen and seeded were investigated according to different seeding temperatures of $-5^{\circ}C$, $-10^{\circ}C$, or $-l5^{\circ}C$ and also according to different concentration of glycerol of 2%, 5% and 10%. In addition, post-thaw motility of canine sperm frozen by direct freezing in a deep freezer or programmed freezing in a programmed cell freezer was investigated. Post-thaw motility of canine sperm was compared according to different seeding temperatures : The sperm seeded at $-5^{\circ}C$ showed considerably higher post-thaw motility than that of non-seeding, and that seeded at $-10^{\circ}C$, or $-l5^{\circ}C$, respectively, in 2% and 5% glycerol groups on both 2 and 7day after freezing(p<0.05). In 10% concentration of glycerol, the sperm seeded at each seeding temperature showed considerably higher post-thaw motility than that of non-seeding group on day 7 after freezing(p<0.01). Post-thaw viability of canine sperm was compared according to different seeding temperatures : The sperm seeded at $-5^{\circ}$ showed significantly higher post-thaw motility than that of non-seeding, and that seeded at $-10^{\circ}C$, or $-l5^{\circ}C$, in 5% and 10% glycerol groups on day 7 after freezing(p< 0.05). In comparison of post-thaw motility of canine sperm seeded according to different concentration of glycerol, 5% glycerol group and 10% glycerol group showed considerably higher post-thaw motility than 2% glycerol group without difference between those two groups in all seeding temperatures($-5^{\circ}C$, $-10^{\circ}C$ and $-l5^{\circ}C$) on day 2 and 7 after freezing(p<0.01). In comparison of post-thaw viability of canine sperm seeded according to different concentration of glycerol, 5% glycerol group and 10% glycerol group showed the same considerably higher post-thaw viability than 2% glycerol group on each thawing day(p<0.01). The canine sperm frozen and seeded by programmed freezing method showed considerably higher post-thaw motility than that frozen by direct freezing method in all different seeding temperatures($-5^{\circ}C$, $-10^{\circ}C$ and $-l5^{\circ}$). These results indicated that the higher post-thaw motility and viability was obtained in the spermatozoa seeded than that of non-seeding, that among different seeding temperatures of $-5^{\circ}C$, $-10^{\circ}C$ and $-l5^{\circ}C$, the sperm seeded at $-5^{\circ}C$ showed higher post-thaw motility and viability than the other temperatures, also among different concentrations fof glycerol of 2%, 5% and 10%, the sperm frozen and seeded in 5% and 10% concentration of glycerol showed higher post-thaw motility and viability than that in 2% of glycerol, and that the sperm frozen and seeded by programmed freezing method showed higher motility than that by direct freezing method.

• Restorative Dentistry and Endodontics
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• 제35권4호
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• pp.257-266
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• 2010

본 연구의 목적은 미성숙 우치를 가타퍼챠 및 다양한 포스트와 코아 시스템을 이용하여 수복한 후 술식에 따른 파절 강도를 측정하였다. 우치의 백악상아경계 상방 8 mm, 하방 12 mm 지점을 절단하여 제작한 미성숙 우치 모델에서 가타퍼챠와 이원중합형 복합레진 LuxaCore로 코어 수복을 시행하거나, 각각 D.T. LIGHT-POST, ParaPost XT 및 다양한 크기의 EverStick Post와 LuxaCore로 수복하였다. 이후 시편을 72시간 동안 증류수에 저장한 후 6,000회의 thermocycling을 진행하였다. 실험적으로 치주인대의 물성을 재현하고, Instron에 시편을 45도로 위치시켜 압축부하를 가해 파절 강도를 측정하고, 파절 부위를 분석하였다. 실험 결과, 포스트를 이용하여 수복하였을 때 파절 강도가 통계적으로 유의하게 증가하였고(p < 0.05), 포스트의 종류 및 적합도는 결과에 통계적으로 유의한 차이를 나타내지 않았다. 대부분의 시편에서 수복 가능한 파절이 나타났으며, 실험군에 따른 파절 부위의 유의한 차이는 나타나지 않았다. 이상의 결과로 볼 때 미성숙 치아의 상기 치근 강화 술식은 치아의 파절 강도를 증가시키고, 포스트의 종류 및 적합도는 파절 저항성에 거의 영향을 미치지 않는 것으로 나타났다.

• The Korean Journal of Pain
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• 제32권1호
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• pp.55-56
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• 2019

• Journal of Korean Neurosurgical Society
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• 제51권5호
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• pp.262-267
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• 2012

Objective : We aimed to investigate the correlation between the success of recanalization and a modified version of the Qureshi grading system in acute ischemic stroke patients. Methods : We retrospectively analyzed the intra-arterial thrombolysis (IAT) records of 37 patients who were evaluated by Thrombolysis in Myocardial Infarction (TIMI) and a modified version of the Qureshi grading systems as follows : 1) post-IAT Qureshi grade, 2) modified ${\Delta}$ Qureshi grade : pre-IAT group grade - post-IAT group grade (grade 1 : Qureshi grades 0-2 and grade 2 : Qureshi grade 3-5) and 3) ${\Delta}$ Qureshi grade (post-IAT Qureshi grade - pre-IAT Qureshi grade). Successful recanalization was defined as follows : 1) post-IAT TIMI grades 2 and 3, 2) post-IAT Qureshi grade 0-2, 3) modified ${\Delta}$ Qureshi grade=1, and 4) ${\Delta}$ Qureshi grade of ${\geq}2$ and/or post-IAT Qureshi grade=0. We investigated the correlation between the post-IAT TIMI grade and the modified Qureshi grade and also compared the various grading systems with modified Rankin Scale scores for evaluating the clinical outcome at 3 months. Results : The post-IAT Qureshi grade and ${\Delta}$ Qureshi grade and/or post-IAT Qureshi grade were significantly correlated with the TIMI grade (${\gamma}$=0.976 and, 0.942, respectively). Further, post-IAT Qureshi grade and ${\Delta}$ Qureshi grade and/or post-IAT Qureshi grade showed a significantly stronger association with clinical outcome than did the post-IAT TIMI grade (p=0.001 and, 0.000 vs. 0.083, respectively). Conclusion : Our preliminary results suggest that the modified Qureshi grading system is a useful tool for assessing the success of recanalization after IAT.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.415-426
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• 2010

Post-grouting for the drilled shaft is known to increase the end bearing capacity of pile 2~3 times higher by consolidating and reinforcing the disturbed ground containing slime around the pile end. However, the general design guideline for post-grouting has not been established yet in Korea. Especially in the domestic application, the post-grouting is employed just for repairing the pile with the unacceptable resistance rather than for increasing the design resistance of pile. Therefore, little is reported about the effect of post-grouting on the pile resistance itself. In this study, the effect of post-grouting on the resistance of drilled shafts installed in the weathered rock in Korea was estimated by performing the bi-directional load tests on the piles with and without the post-grouting. The test results presented that the initial slope of end bearing-base displacement curve in the pile with post-grouting was 4 times higher than that without post-grouting. At the acceptable settlement (1% of pile diameter), the end bearing capacities of piles with and without the post-grouting were estimated to be 12.0 MPa and 7.0 MPa, respectively, indicating that the post-grouting could increase the end bearing resistance of pile in weathered rock more than 70%.

• Restorative Dentistry and Endodontics
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• 제38권4호
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• pp.215-221
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• 2013

Objectives: To determine the retentive strength and failure mode of undercut composite post, glass fiber post and polyethylene fiber post luted with flowable composite resin and resin-cement. Materials and Methods: Coronal parts of 120 primary canine teeth were sectioned and specimens were treated endodontically. The teeth were randomly divided into 6 groups (n = 20). Prepared root canals received intracanal retainers with a short composite post, undercut composite post, glass fiber post luted with flowable resin or resin-cement, and polyethylene fiber post luted with flowable resin or resin-cement. After crown reconstruction, samples were tested for retentive strength and failure mode. Statistical analysis was done with one-way ANOVA and Tukey tests (p < 0.05). Results: There were statistically significant differences between groups (p = 0.001). Mean bond strength in the undercut group was significantly greater than in the short composite post (p = 0.030), and the glass fiber post (p = 0.001) and the polyethylene fiber post group luted with resin-cement (p = 0.008). However, the differences between the undercut group and the groups with flowable composite as the luting agent were not significant (p = 0.068, p = 0.557). Adhesive failure was more frequent in the fiber post groups. Conclusions: Although the composite post with undercutting showed the greatest resistance to dislodgement, fiber posts cemented with flowable composite resin provided acceptable results in terms of retentive strength and fracture mode.

• Journal of Magnetics
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• 제15권4호
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• pp.179-184
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• 2010

We have investigated the effects of post annealing on iron oxide nanoparticles synthesized by the novel hydrothermal synthesis method with the $FeSO_4{\cdot}7H_2O$. To investigate the post annealing effect, the as-synthesized iron oxide nanoparticles were annealed at different temperatures in a vacuum chamber. The morphological, structural and magnetic properties of the iron oxide nanoparticles were investigated with high resolution X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Mossbauer spectroscopy, and vibrating sample magnetometer analysis. According to the XRD and HRTEM analysis results, as-synthesized iron oxide nanoparticles were only magnetite ($Fe_3O_4$) phase with face-centered cubic structure but post annealed iron oxide nanoparticles at $700^{\circ}C$ were mainly magnetite phase with trivial maghemite ($\gamma-Fe_2O_3$) phase which was induced in the post annealing treatment. The crystallinity of the iron oxide nanoparticles is enhanced by the post annealing treatment. The particle size of the as-synthesized iron oxide nanoparticles was about 5 nm and the particle shape was almost spherical. But the particle size of the post annealed iron oxide nanoparticles at $700^{\circ}C$ was around 25 nm and the particle shape was spherical and irregular. The as-synthesized iron oxide nanoparticles showed superparamagnetic behavior, but post annealed iron oxide nanoparticles at $700^{\circ}C$ did not show superparamagnetic behavior due to the increase of particle size by post annealing treatment. The saturation of magnetization of the as-synthesized nanoparticles, post annealed nanoparticles at $500^{\circ}C$, and post annealed nanoparticles at $700^{\circ}C$ was found to be 3.7 emu/g, 6.1 emu/g, and 7.5 emu/g, respectively. The much smaller saturation magnetization value than one of bulk magnetite can be attributed to spin disorder and/or spin canting, spin pinning at the nanoparticle surface.

• 한국응급구조학회지
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• 제20권2호
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• pp.37-49
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• 2016

Purpose: This study investigated the current status of post-traumatic stress and related factors among safety managers in Korea National Parks. Methods: The study subjects were 109 safety managers working in Korea National Parks. General characteristics, job-related characteristics, experience of traumatic events and post-traumatic stress were collected by self-reported questionnaires through the mail. The associated factors with post-traumatic stress was analyzed by t-test, ANOVA and multiple linear regression. Results: Overall score of post-traumatic stress was $10.32{\pm}11.37$ and 12.8% was the high-risk group of post-traumatic stress disorder. In simple analysis, score of post-traumatic stress was associated with drinking frequency, disease history, duration of career, delay of rescue, provided the break, rest space and the number of experiences of traumatic events. Finally, the score of post-traumatic stress was significantly higher in subjects who experienced 3 (B=9.141, SE=3.538) or more than 4 (B=11.367, SE=3.063) traumatic events compared to subjects without experience of traumatic event. Conclusion: The score of post-traumatic stress was $10.32{\pm}11.37$ and 12.8% was the high-risk group among safety managers in Korea National Parks. Post-traumatic stress was associated with the experience of traumatic events. Management of safety managers after mobilization or experience of traumatic events will be helpful to decrease of post-traumatic stress.