• Journal of Periodontal and Implant Science
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• v.48 no.2
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• pp.103-113
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• 2018

Purpose: The purpose of this retrospective study with 4-12 years of follow-up was to compare the marginal bone loss (MBL) between external-connection (EC) and internal-connection (IC) dental implants in posterior areas without periodontal or peri-implant disease on the adjacent teeth or implants. Additional factors influencing MBL were also evaluated. Methods: This retrospective study was performed using dental records and radiographic data obtained from patients who had undergone dental implant treatment in the posterior area from March 2006 to March 2007. All the implants that were included had follow-up periods of more than 4 years after loading and satisfied the implant success criteria, without any peri-implant or periodontal disease on the adjacent implants or teeth. They were divided into 2 groups: EC and IC. Subgroup comparisons were conducted according to splinting and the use of cement in the restorations. A statistical analysis was performed using the Mann-Whitney U test for comparisons between 2 groups and the Kruskal-Wallis test for comparisons among more than 2 groups. Results: A total of 355 implants in 170 patients (206 EC and 149 IC) fulfilled the inclusion criteria and were analyzed in this study. The mean MBL was 0.47 mm and 0.15 mm in the EC and IC implants, respectively, which was a statistically significant difference (P<0.001). Comparisons according to splinting (MBL of single implants: 0.34 mm, MBL of splinted implants: 0.31 mm, P=0.676) and cement use (MBL of cemented implants: 0.27 mm, MBL of non-cemented implants: 0.35 mm, P=0.178) showed no statistically significant differences in MBL, regardless of the implant connection type. Conclusions: IC implants showed a more favorable bone response regarding MBL in posterior areas without peri-implantitis or periodontal disease.

• Korean Journal of Childcare and Education
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• v.8 no.1
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• pp.25-44
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• 2012

The purpose of this study was to conduct a systematic review of the previous studies done on the child-care teacher's turnover intentions. From 2001 to 2011, 33 articles which reforted primary empirical data met the criteria for inclusion in the meta-analysis. The results of this study are as follo ws: First, included in the main factors related to child-care teachers' turnover intentions were a job-related variable, an organizational internal variable and an organizational external variable. Second, the most influential protective variable related to the child-care teacher's turnover intentions among the set of organizational external variables was work-time followed by welfare, education and training, remuneration, social recognition and promotion system. Third, the most influential protective variable related to child-care teachers' turnover intentions among the set of job-related variables was teacher efficacy followed by job satisfaction, participation of decision making, performance, work-autonomy and work-professionalism. Fourth, the most influential protective variable related to the child-care teacher's turnover intentions among the set of organizational internal variables was personal relations followed by relationships with the director and relationships with colleagues. The effect size of these variables was large. Fifth, the results of meta-regression analysis revealed that the survey area and years had no significant effect on overall effect sizes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.2
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• pp.114-120
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• 2007

The augmentation of soft tissue defects is one of the critical problems in the oral and maxillofacial surgery. Various types of graft materials, both autologous and non-autologous, have been used for the augmentation of soft tissue in the facial region. However, it is not easy to choose an ideal material for soft tissue augmentation because each has its advantages and disadvantages. An ideal graft material should meet the following criteria : it should not leave a scar at the area from which it was taken; should have less likelihood of causing infection; should feel natural after implanted; and should be not absorbed. Among the materials meeting these criteria, human dermis and artificial dermis are commonly used for clinical purposes. The present study was aimed to investigate and compare the resorption rate and the histological change following the use of the autologous dermis, the human homogenous dermis $Alloderm^{(R)}$, and the artificial dermis $Terudermis^{(R)}$ to reconstruct the soft tissue defect. Twenty mature rabbits of either sex, weighing about 2 ㎏, were used. Each rabbit was transplanted with the autologous dermis, $Alloderm^{(R)}$, and $Terudermis^{(R)}$ size $1{\times}1-cm$ at the space between the external abdominal oblique muscle and the external abdominal oblique fascia. They were then divided into 4 groups (n=5 each) according to the time elapsed after the surgery: 1, 2, 4, and 8 weeks. The resorption rate was calculated by measuring the volume change before and after the transplantation, and H-E stain was preformed to observe the histological changes. The resorption rate after 8 weeks was 21.5% for the autologous dermis, 16.0% $Alloderm^{(R)}$, and 36.4% $Terudermis^{(R)}$, suggesting that $Alloderm^{(R)}$ is the most stable while $Terudermis^{(R)}$ is the most unstable. In microscopic examinations, the autologous dermis graft was surrounded by inflammatory cells and showed foreign body reactions. The epidermal inclusion cyst was observed in the autologous dermis graft. $Terudermis^{(R)}$ and $Alloderm^{(R)}$ demonstrated neovascularization and the progressive growth of new fibroblast. The results suggest that $Terudermis^{(R)}$ and $Alloderm^{(R)}$ can be availably for substituting the autologous dermis.

• Journal of Korean Classical Literature and Education
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• no.35
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• pp.5-46
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• 2017

This study aims to investigate the context of materials in literature textbooks and the awareness about the educational value of classical literature, as part of an interest in literature education phenomena. This study accepts the premise that textbooks affect the practice of classical literature education and, in particular, materials in textbooks are chosen according to the intentions, demands, and perspectives of education in specific social conditions. I divided the educational value of classical literature into two categories, classical and literary value, and investigated the actual conditions and context of materials of literature textbooks based on the 2009 revised curriculum and the 2011 revised curriculum. Classical literature is generally alienated and excluded; contemporary literature materials are mostly included and organized in the domains of 'the role of literature', 'reception and production of literature' and 'literature and life.' In addition, the tendency to heighten classical value and diminish literary value is deepening. In order to solve the problem that classical literature is only included as the product of the past, changes must be made not just to the curriculum, which are external changes, but to the awareness of the essence of classical literature, which are internal changes. Above all, generality as 'literature' and the sense of distance about space and time as 'classic' should be connected to various relationships which respond to problematic situations and the demands of learners. Based on the relationships, we can expect a rich diversity of contexts and aspects of included classical literature. In addition, an extension of the width and scope of included classical literature is anticipated. The reduction of workload, the advent of the concept of capability and the dissolution of traditional literature concepts are the changes of external environment, which is continuously requiring renewed investigation into classical literature beyond simple appropriateness.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.1
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• pp.34-42
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• 2013

Our study is to review Chinese traditional medicine's journals about the diagnosis and treatment of spasmodic torticollis such as category, syndrome differentiation, acupoints of treatment, and herbal medicine. The journal search was performed using the search engine of China Academic Journal (CAJ) and China Doctor/Master's Dissertation (CDMD) in China National Knowledge Infrastructure (CNKI) from January 1982 to October 2012. Searching key words were the diverse combination of "spasmodic torticollis", "cervical dystonia", "Chinese traditonal medicine", "herbal medicine", "acupuncture", and "syndrome differentiation". The inclusion criteria was all kinds of journals including Chinese traditional medicine approach except for experiment study. The category, syndrome differentiation, acupoints of treatment, and herbal medicine from finally selected journals were extracted and summarized. The fourty-seven Chinese journals were selected finally. The category was divided into wind syndrome, trembling syndrome, convulsive syndrome, and convulsions. The syndrome differentiation was classified as internal stirring of liver wind, yin-blood depletion, invasion of external contraction, uncontrol of governor vessel, internal obstruction of phlegm turbidity, dual deficiency of qi and blood, and blood stasis due to qi stagnation. The combination of acupoints to unblock the meridian and dissipate binds and to tonify governor vessel and repel tremor was mainly used in acupuncture treatment. Galgun-tang or galgun-tanggami was primarily used and the others were the prescriptions to tonify liver and kidney, to calm convulsion, and to dispeling wind-phlegm. We suggests that spasmodic torticollis could be treated using Korean medicine's approach in Korea.

• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.43-49
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• 2005

In the concrete structures, the magnitude and distribution of the temperature due to the heat of hydration are related to the thermal properties of each component composed of the concrete, the initial temperature, the type of formwork, and the ambient temperature of exposed surfaces. Even though the reinforcing steel bar has completely different thermal properties, it has been excluded. In the thermal analysis on the concrete structures. In this study, finite element analysis was performed on the concrete structures including the reinforcing steel in order to investigate their effect on temperature and stress distribution due to the heat of hydration. As the steel ratio increased, the maximum temperature and the internal-external temperature difference decreased by 32.5% and 10%, respectively. It is clear that the inclusion of reinforcing steel bars on the heat of hydration analysis is indispensable to obtain realistic solutions for the prediction of the maximum temperature and stresses

• International Journal of Oral Biology
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• v.39 no.4
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• pp.229-236
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• 2014

Reactive oxygen species (ROS) and nitrogen species (RNS) are implicated in cellular signaling processes and as a cause of oxidative stress. Recent studies indicate that ROS and RNS are important signaling molecules involved in nociceptive transmission. Xanthine oxidase (XO) system is a well-known system for superoxide anions ($O{_2}^{{\cdot}_-}$) generation, and sodium nitroprusside (SNP) is a representative nitric oxide (NO) donor. Patch clamp recording in spinal slices was used to investigate the role of $O{_2}^{{\cdot}_-}$ and NO on substantia gelatinosa (SG) neuronal excitability. Application of xanthine and xanthine oxidase (X/XO) compound induced membrane depolarization. Low concentration SNP ($10{\mu}M$) induced depolarization of the membrane, whereas high concentration SNP (1 mM) evoked membrane hyperpolarization. These responses were significantly decreased by pretreatment with phenyl N-tert-butylnitrone (PBN; nonspecific ROS and RNS scavenger). Addition of thapsigargin to an external calcium free solution for blocking synaptic transmission, led to significantly decreased X/XO-induced responses. Additionally, X/XO and SNP-induced responses were unchanged in the presence of intracellular applied PBN, indicative of the involvement of presynaptic action. Inclusion of GDP-${\beta}$-S or suramin (G protein inhibitors) in the patch pipette decreased SNP-induced responses, whereas it failed to decrease X/XO-induced responses. Pretreatment with n-ethylmaleimide (NEM; thiol-alkylating agent) decreased the effects of SNP, suggesting that these responses were mediated by direct oxidation of channel protein, whereas X/XO-induced responses were unchanged. These data suggested that ROS and RNS play distinct roles in the regulation of the membrane excitability of SG neurons related to the pain transmission.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.444-444
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• 2011

Recently, patterned magnetic films and elements attract a wide interest due to their technological potentials in ultrahigh-density magnetic recording and spintronic devices. Among those patterned magnetic structures, magnetic anti-dot patterning induces a strong shape anisotropy in the film, which can control the magnetic properties such as coercivity, permeability, magnetization reversal process, and magneto-resistance. While majority of the previous works have been concentrated on anti-dot arrays with a single magnetic layer, there has been little work on multilayered anti-dot arrays. In this work, we report on study of the magnetic properties of bilayered anti-dot system consisting of upper perforated Co layer of 40 nm and lower continuous Ni layer of 5 nm thick, fabricated by photolithography and wet-etching processes. The magnetic hysteresis (M-H) loops were measured with a superconducting-quantum-interference-device (SQUID) magnetometer (Quantum Design: MPMS). For comparison, investigations on continuous Co thin film and single-layer Co anti-dot arrays were also performed. The magnetic-domain configuration has been measured by using a magnetic force microscope (PSIA: XE-100) equipped with magnetic tips (Nanosensors). An external electromagnet was employed while obtaining the MFM images. The MFM images revealed well-defined periodic domain networks which arise owing to the anisotropies such as magnetic uniaxial anisotropy, configurational anisotropy, etc. The inclusion of holes in a uniform magnetic film and the insertion of a uniform thin Ni layer, drastically affected the coercivity as compared with single Co anti-dot array, without severely affecting the saturation magnetization ($M_s$). The observed changes in the magnetic properties are closely related to the patterning that hinders the domain-wall motion as well as to the magneto-anisotropic bilayer structure.

• Safety and Health at Work
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• v.8 no.1
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• pp.11-18
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• 2017

The purpose of this review is to name and describe the important factors of musculoskeletal strain originating from pushing and pulling tasks such as cart handling that are commonly found in industrial contexts. A literature database search was performed using the research platform Web of Science. For a study to be included in this review differences in measured or calculated strain had to be investigated with regard to: (1) cart weight/ load; (2) handle position and design; (3) exerted forces; (4) handling task (push and pull); or (5) task experience. Thirteen studies met the inclusion criteria and proved to be of adequate methodological quality by the standards of the Alberta Heritage Foundation for Medical Research. External load or cart weight proved to be the most influential factor of strain. The ideal handle positions ranged from hip to shoulder height and were dependent on the strain factor that was focused on as well as the handling task. Furthermore, task experience and subsequently handling technique were also key to reducing strain. Workplace settings that regularly involve pushing and pulling should be checked for potential improvements with regards to lower weight of the loaded handling device, handle design, and good practice guidelines to further reduce musculoskeletal disease prevalence.

• 한국사회정책
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• v.25 no.2
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• pp.243-280
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• 2018

This paper examines the discussion on the income-led growth known as the core economic strategy of Moon's administration in terms of Korean welfare regime. Although the income-led growth strategies have presented various issues, the income-led growth strategy seems to be a timely alternative discourse that emphasizes the demand side, considering supply-oriented growth strategies have caused long-term recession and deepening of inequality. It is important that the income-led growth strategy places social expenditures as an important growth engine for virtuous cycle of production and consumption. However, this paper has confirmed that simply raising wages and increasing social expenditure do not increase the aggregate demand and production. Moreover, empirical studies have shown that the inclusion of external sectors and liabilities into the analysis weakens the wage-led growth of the Korean economy. For this reason, this study concluded that the government's sophisticated policy intervention is necessary for the increase of real wages and social spending to be economic growth.