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A Study on the Horizontal Consolidation and Permeability Characteristics of Decomposed Mudstone Soil in Pohang (이암풍화토의 횡방향압밀 및 투수특성)

  • 김영수;김기영;백영식
    • Journal of the Korean Geotechnical Society
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    • v.16 no.1
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    • pp.31-42
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    • 2000
  • Consolidation and permeability are major engineering properties of soil. In clay, coefficient of permeability and consolidation can be calculated by incremental loading consolidation test. However, it is known that the incremental loading test has several deficiencies including long testing time, non-uniform stress state, very soft clay and problem of back pressure saturation. Specially, it is not performed with horizontal consolidation test. Several methods have been proposed for obtaining reliable values of $C_v$. Among these, the square root of time-fitting method proposed by Taylor(1948) and logarithm of time-fitting method, also called Casagrande's method, are used extensively in soil engineering practice. But these methods are not amenable for the absence of initial linear portion and have the difficulties involved in distinguishing secondary compression from primary compression. Rowecell consolidation tests were carried out in this study with different trimming axis and sample size. The results were compared with those of other methods; Casagrande,$Taylor,\; Casagrande,\; Hyperbolic,\; \delta/t-logt$. From the results, we explained a relationship between horizontal coefficient of permeability and void ratio was obtained. Finally, the directly measured horizontal coefficient of permeability obtained by using the Rowecell was compared with the permeability derived indirectly from the consolidation test result.

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Topiramate for the Treatment of Binge Eating Disorder or Bulimia Nervosa : A Systemic Review of Human Clinical Studies and Case Reports (Topiramate의 신경성 폭식증 치료효과: 국내외 보고된 임상연구결과 및 치험사례 중심으로)

  • Lee, Yu-Jeung;Bang, Joon-Seok
    • Korean Journal of Clinical Pharmacy
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    • v.17 no.1
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    • pp.6-12
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    • 2007
  • The clinical investigations above suggest that topiramate may be an effective agent in the treatment of BED or BN by reducing binging/purging episodes, improving the HRQOL, and decreasing weight. The case report and case series also support these findings. However, there are several limitations in the above studies and cases. All these had relatively small sample size, and two of them were only 10-week-period studies. Optimal duration of treatment with topiramate in patients with BED or BN is unknown. As most clinicians treat the patient with BED or BN for 6 to 12 months and then reassess, at least 6 months period is needed to show its efficacy. One of studies included only women in the patient group. In the case series, all patients had severe comorbid mood disorders such as major depression and bipolar disorder besides BN. Therefore, notwithstanding its clinical usefulness, additional researches are needed to define the role and the benefits of topiramate in the treatment of BED or BN more thoroughly.

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The Certification Role by the Types of Venture Capitalists in KOSDAQ (벤처캐피탈회사의 유형과 보증역할에 대한 연구)

  • Yoon, Byung-Seop
    • The Korean Journal of Financial Management
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    • v.20 no.1
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    • pp.29-60
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    • 2003
  • This study investigates the certification role by the types of venture capitalists in KOSDAQ IPOs. The sample covers 88 venture companies listed on KOSDAQ from January, 1997 to December, 2001. The major results are as follows. Firstly, IPOs of firms backed by New Technology Business Investment Companies are less underpriced than those of firms backed by Small Business Investment Companies. The underpricing difference between two groups is statistically significant. This sheds light on the evidence of the certification role of venture capitalist in KOSDAQ IPOs market. Secondly, our result also attests the certification role by the types of venture capitalists among Small Business Investment Company. IPOs backed by yen拉re capitalists of financial institutions are less underpriced than those backed by venture capitalists of individual wealthy investors. The underpricing difference between two groups is statistically significant. Finally, underpricing of New Technology Business Investment Company-backed IPOs is less than that of Small Business Investment Company-backed IPOs. In addition, we found that the size of underpricing is affected by business history, sub-scription ratio, and total assets prior to registration.

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Quality Evaluation of Red seabream, Pagrus major by Chemoenzymatic Method (효소 화학적 방법에 의한 참돔, Pagrus major의 품질판정)

  • 배진한;김태진;정호진;여해경;심길보;조영제
    • Journal of Aquaculture
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    • v.17 no.3
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    • pp.167-172
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    • 2004
  • Chemoenzymatic method was used in this study to evaluate the quality of cultured red seabrim. Level of ATP related compounds, ATPase and Adenylate energy charge (AEC) well reflected changes in condition of fish. ATP level in the muscle of exercised cultured red seabream was decreased significantly during cultured period. In contrast, the level of ADP in the muscle was increased during the period. Level of ATP related compounds in the muscle of cultured red seabream without exercise didn't show significant difference compared to the exercised group. AEC value in muscle of cultured red seabream without exercise was 0.89$\pm$0.02, while AEC value of the exercised group was 0.88$\pm$0.04. ATP and AEC levels among different size of fish did not show any significant difference. AEC value in all sample was higher than 0.8, indicating that the condition of cultured fish was healthy. Activity of Mg2$^{+}$ (+Ca2$^{+}$), Mg2$^{+}$ (-Ca2$^{+}$) and Ca2$^{+}$-ATPase during culture period did not change significantly, regardless of exercise. Therefore, the AEC appears to have some validity as fish health indicator.

An Emotional Self-Regulation Program for Obese Children: Pilot Study Using Mixed Methods (비만아동을 위한 정서적 자기조절 프로그램의 개발 및 효과: 혼합방법론의 적용)

  • Kim, Hee-Soon;Ma, Yu-Mi;Park, Ji-Young;Kim, Seung-Hyun
    • Child Health Nursing Research
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    • v.19 no.3
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    • pp.187-197
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    • 2013
  • Purpose: The purpose of the study was to develop an emotional self-regulation program for obese children and to examine the program's effectiveness on depression, eating habits, and body mass index. Methods: The emotional self-regulation program was developed from theory-based strategies and a pre-post pilot study was conducted with 46 children (19: intervention, 27: control). The program included 6 weekly group sessions over 2 months. The embedded experimental model of concurrent mixed methods was used to better understand research outcomes by converging both quantitative and qualitative data. Anthropometric measurements and surveys were performed before and after the intervention. Three focus group interviews were conducted with all participants after intervention to explore their experiences. Results: The intervention group displayed decreased depression levels in the quantitative outcomes. The participants also expressed positive outcomes such as improvements in confidence, impulse management, intimacy, happiness, and losing weight. Conclusion: These findings suggest that emotional self-regulation skills are crucial factors for obese children not only to manage their emotional problems but also to control their weight. Further research is needed with a larger sample size and randomized controlled trials.

An occlusal contact analysis of lateral mandibular movement using T-Scan system (T-Scan system을 이용한 하악 측방운동 시 교합접촉 분석)

  • Song, Joo-Hun;Joo, Se-Jin;Lee, Ho-Sun;Kang, Dong-Wan;Lee, Gyeong-Je
    • The Journal of Korean Academy of Prosthodontics
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    • v.53 no.2
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    • pp.128-137
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    • 2015
  • Purpose: Most of the former studies about the occlusal contact patterns during the mandibular movement focused on foreigner. The purpose of this study is analyzing the occlusal contacts of young Koreans by using T-Scan system. Materials and methods: The sample size was 87 and the occlusal contacts of each right and left lateral movements were measured from the maximum intercuspation to the 3mm excursive position for three times respectively. All of the occlusal contacts were double checked through the thin metal foil. The results were categorized as two; 1) considering occlusal contact patterns on working side only, 2) considering occlusal contact patterns on working and nonworking sides. Results: The results showed that the nonworking side occlusal contacts play major roles in the lateral mandibular movement. In both cases of considering with and without the nonworking side occlusal contacts, the group function was the most prevalent. In the working side, the contacts were the most frequent in canine and the frequency of contacts was decreased as the distance was increased from canine to molar. In the nonworking side, the contacts were the most frequent in second molar. And the gender factor was statistically significant (${\alpha}$=.05), as females have more nonworking side occlusal contacts in this study. Conclusion: Among the three factors of anterior guidance, the group function was the most dominant factor. The analysis of 87 samples showed that canine contact was the most frequent in the working side and second molar contact was the most common in the nonworking side.

The influence of root surface distance to alveolar bone and periodontal ligament on periodontal wound healing

  • Montevecchi, Marco;Parrilli, Annapaola;Fini, Milena;Gatto, Maria Rosaria;Muttini, Aurelio;Checchi, Luigi
    • Journal of Periodontal and Implant Science
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    • v.46 no.5
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    • pp.303-319
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    • 2016
  • Purpose: The purpose of this animal study was to perform a 3-dimensional micro-computed tomography (micro-CT) analysis in order to investigate the influence of root surface distance to the alveolar bone and the periodontal ligament on periodontal wound healing after a guided tissue regeneration (GTR) procedure. Methods: Three adult Sus scrofa domesticus specimens were used. The study sample included 6 teeth, corresponding to 2 third mandibular incisors from each animal. After coronectomy, a circumferential bone defect was created in each tooth by means of calibrated piezoelectric inserts. The experimental defects had depths of 3 mm, 5 mm, 7 mm, 9 mm, and 11 mm, with a constant width of 2 mm. One tooth with no defect was used as a control. The defects were covered with a bioresorbable membrane and protected with a flap. After 6 months, the animals were euthanised and tissue blocks were harvested and preserved for micro-CT analysis. Results: New alveolar bone was consistently present in all experimental defects. Signs of root resorption were observed in all samples, with the extent of resorption directly correlated to the vertical extent of the defect; the medial third of the root was the most commonly affected area. Signs of ankylosis were recorded in the defects that were 3 mm and 7 mm in depth. Density and other indicators of bone quality decreased with increasing defect depth. Conclusions: After a GTR procedure, the periodontal ligament and the alveolar bone appeared to compete in periodontal wound healing. Moreover, the observed decrease in bone quality indicators suggests that intrabony defects beyond a critical size cannot be regenerated. This finding may be relevant for the clinical application of periodontal regeneration, since it implies that GTR has a dimensional limit.

Effect of scaling and root planing on the expression of anti-inflammatory cytokines (IL-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid of electronic cigarette users and non-smokers with moderate chronic periodontitis

  • Al-Hamoudi, Nawwaf;Alsahhaf, Abdulaziz;Deeb, Modhi Al;Alrabiah, Mohammed;Vohra, Fahim;Abduljabbar, Tariq
    • Journal of Periodontal and Implant Science
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    • v.50 no.2
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    • pp.74-82
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    • 2020
  • Purpose: The aim of this cross-sectional study was to investigate the effect of scaling and root planing (SRP) on the expression of anti-inflammatory cytokines (interleukin [IL]-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid (GCF) of electronic cigarette users and non-smokers with moderate chronic periodontitis (CP). Methods: Electronic cigarette users and non-smokers with CP were included in the study. Full-mouth plaque and gingival indices, probing depth (PD), clinical attachment loss (CAL), and marginal bone loss (MBL) were assessed. The GCF was collected, and its volume and levels of IL-4, IL-9, IL-10, and IL-13 were assessed. These parameters were evaluated at baseline and 3 months after SRP. The sample size was estimated, and comparisons between groups were performed. P<0.05 was considered to indicate statistical significance. Results: Thirty-six electronic cigarette users (47.7±5.8 years old) and 35 non-smokers (46.5±3.4 years old) with CP were included. At baseline, there were no differences in plaque index (PI), PD, CAL, MBL, and GCF IL-4, IL-9, IL-10, and IL-13 between electronic cigarette users and nonsmokers. At the 3-month follow-up, there were no significant differences in PI, gingival index (GI), PD, CAL, and MBL in electronic cigarette users compared to baseline, while there were significant reductions in PI, GI, and PD among non-smokers. At the 3-month follow-up, GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly elevated in both groups (P<0.05) compared to baseline. The increases in GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly higher in non-smokers (P<0.05) than in electronic cigarette users at the 3-month follow-up. Conclusions: Levels of GCF IL-4, IL-9, IL-10, and IL-13 increased after SRP in electronic cigarette users and non-smokers with CP; however, the anti-inflammatory effect of SRP was more profound in non-smokers than in electronic cigarette users.

The Study of Personality Types between Pediatric and Other Dental Residents (소아치과 전공의와 타과 전공의 간 성격 유형 연구)

  • Jang, Seokhun;Kim, Sunah;Nam, Okhyung;Kim, Misun;Choi, Sungchul;Lee, Hyoseol
    • Journal of the korean academy of Pediatric Dentistry
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    • v.44 no.3
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    • pp.327-334
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    • 2017
  • The purpose of this study was to compare the personality types between pediatric and other dental residents. 77 pediatric dental residents and 71 other dental residents in Korea were surveyed by Myers-Briggs Type Indicator questionnaire. Myers-Briggs Type Indicator (MBTI) had 4 personality dichotomies consisting of 2 opposite characteristics that were extraversion / introversion, sensing / intuition, thinking / feeling, and judging / perception. Combinations of these four dichotomies could make 16 personality types. The percentage of pediatric dental residents was higher in sensing and judging, but there were no statistically differences. The majority of personal type was ISTJ in both groups. Statistical significance observed only in gender. The ratio of thinking was higher in male than in female (p < 0.05). The meaning of this study was the first survey performed on the personality types between pediatric dental residents and other dental residents in Korea. Further study with pre-survey orientation and increased sample size should proceed.

The Effect of the Adjustment Stress and the Social Support on the Depressive Symptoms of the North Korean Defectors (탈북자의 적응스트레스와 사회적 지지가 우울성향에 미치는 영향)

  • Kim, Mee-Ryoung
    • Korean Journal of Social Welfare
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    • v.57 no.1
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    • pp.193-217
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    • 2005
  • Due to the increasing concerns with the North Korean defectors, the researches have been increased. When it is compared with other areas, the researches about the North Korean defectors are rare. The sample size of this study is 164, which makes it possible to do statistical inferences. As statistical methods, t-test, ANOVA and hierarchical multiple regressions are used. This study examines the effect of the adjustment stress and the social support on the depressive symptoms. Demographic factors such as gender, age and education are controlled. The context factors-the period of the stay in the third place, the period of residence and the existence of the education in Korea- are used as control variables. The research results show that the level of social participation of the women is higher than that of men. Also, there are differences of the functional social support by the age group. The research result indicates the education of South Korea is an important factor to reduce the depressive symptoms. The research result also shows that the jobless is an important stressor. Among structural social support, the member of religious or social group is an important factor for reducing depressive symptoms. Among functional social support, the emotional social support is an important factor of adaptation, but the effect of instrumental social support is the opposite. Therefore, the adequacy of social support in a specific situation must be considered.

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