• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.236-244
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• 2018

PURPOSE. To determine the discrepancy in monolithic zirconium dioxide crowns made with computer-aided design and computer-aided manufacturing (CAD/CAM) systems by comparing scans of silicone impressions and of master casts. MATERIALS AND METHODS. From a Cr-Co master die of a first upper left molar, 30 silicone impressions were taken. The 30 silicone impressions were scanned with the laboratory scanner, thus obtaining 30 milled monolithic yttrium stabilized zirconium dioxide (YSZD) crowns (the silicone group). They were poured and the working models were scanned, obtaining 30 milled monolithic yttrium stabilized zirconium dioxide (YSZD) crowns (the plaster group). Three predetermined points were analyzed in each side of the crown (Mesial, Distal, Vestibular and Palatal), and the marginal fit was evaluated with SEM (${\times}600$). The response variable is the discrepancy from the master model. A repeated measures ANOVA with two within subject factors was performed to study significance of main factors and interaction. RESULTS. Mean marginal discrepancy was $22.42{\pm}35.65{\mu}m$ in the silicone group and $8.94{\pm}14.69{\mu}m$ in the plaster group. The statistical analysis showed significant differences between the two groups and also among the four aspects. Interaction was also significant (P=.02). CONCLUSION. The mean marginal fit values of the two groups were within the clinically acceptable values. Significant differences were found between the groups according to the aspects studied. Various factors influenced the accuracy of digitizing, such as the design, the geometry, and the preparation guidance, as well as the texture, roughness and the color of the scanned material.

• Korean journal of food and cookery science
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• v.32 no.1
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• pp.65-75
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• 2016

The purpose of this study was to investigate the consumer's current use and recognition for foodservice social enterprises type cafe. During the research, problems regarding the developmental directions of foodservice social enterprises type cafe. A one-to-one survey method was used for data collection, and 301questionnaires among the 309 distributed questionnaires to consumers were analyzed (97.4% response rate). The main results of the study were as follows : with reference to the awareness of the foodservice social enterprise type cafe, a majority of respondents (81.1%) replied that they had knowledge related to the business of social enterprise. Furthermore, regarding how customers came to know about the foodservice social enterprise type cafe results showed that 28.2% of respondents knew about the cafe by acquaintances such as friend, co-worker, family, 23.2% by mass media, and 27.2% by others. Data concerning a companion when visiting the cafe, revealed that more than half of the respondents (80.0%) had visited with friend and co-worker. On problems with using the cafe, approximately 46.2% of the respondents replied that there was lack of public relation and 28.9% replied that it was an uncommon store. Since the findings suggested that the major problem is a lack of promotion, foodservice social enterprises type cafe should prepare organized brochures and guide system to attract customers with various purposes and values. Finally, the promotion for foodservice social enterprise type cafe requires a guidance map.

• The Korean Journal of Pain
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• v.22 no.1
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• pp.52-57
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• 2009

Background: Transforaminal epidural injection (TEI) may be useful to treat unilateral pain that has a dermatomal distribution. In this approach, the needle tip can be placed closer to the dorsal root ganglion and ventral aspect of the nerve root. However many studies have reported that serious complications following TEI occurred more frequently when it was conducted at the cervical level. One of the presumptive mechanisms of the complication is intravascular injection. Therefore this study was conducted to identify the incidence of complications in response to intravascular injections at cervical segments. Methods: This study included all patients, who visited our pain clinic and had radicular symptoms or herpes zoster associated pain. All procedures were conducted under fluoroscopic guidance with contrast enhancement by one of the authors. After the ideal needle position was confirmed by biplanar fluoroscopy, the blood aspiration through the needle hub was evaluated, and a 3 ml mixture of nonionic contrast (2 ml) with normal saline (1 ml) was injected at a rate of 0.3-0.5 ml/sec continuously under real time fluoroscopic visualization. We then classified the contrast spreading pattern as neural, simultaneous neural and vascular, or vascular. Results: A total 71 cervical TEIs were performed. In 26 cases (36.6%), the contrast only spread to the nerve sheath. However, 45 cases (63.4%) showed an intravascular spreading pattern, 37 (52.1%) of which showed a neural and vascular pattern and 8 (11.3%) of which showed only a vascular pattern. Conclusions: Approximately two thirds of the cases of cervical TEI were found to lead to intravascular spreading, which is much higher than the incidence reported in previous studies.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.3
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• pp.285-296
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• 1997

Injury to brain transforms resting astrocytes to their reactive form, the hallmark of which is an increase in glial fibrillary acidic protein (GFAP), the major intermediate filament protein of their cell type. The overall glial response after brain injury is referred to as reactive gliosis. Glial-neuronal interaction is important for neuronal migration, neurite outgrowth and axonal guidance during ontogenic development. Although much attention has been given to glial regulation of neuronal development and regeneration, evidences also suggest a neuronal influence on glial cell differentiation, maturation and function. The aim of the present study was to analyze the effects of glial-hippocampal neuronal co-culture on GFAP expression in the co-cultured astrocytes. The following antibodies were used for double immunostaining chemistry; mouse monoclonal antibodies for confirm neuronal cells, rabbit anti GFAP antibodies for confirm astrocytes. Primary cultured astrocytes showed the typical flat polygonal morphology in culture and expressed strong GFAP and vimentin. Co-cultured hippocampal neurons on astrocytes had phase bright cell body and well branched neurites. About half of co-cultured astrocytes expressed negative or weak GFAP and vimentin. After 2 hour glutamate (0.5 mM) exposure of glial-neuronal co-culture, neuronal cells lost their neurites and most of astrocytes expressed strong CFAE and vimentin. In Western blot analysis, total GFAP and vimentin contents in co-cultured astrocytes were lower than those of primary cultured astrocytes. After glutamate exposure of glial-neuronal co-culture, GFAP and vimentin contents in astrocytes were increased to the level of primary cultured astrocytes. These results suggest that neuronal cell decrease GFAP expression in co-cultured astrocytes and hippocampal neuronal-glial co-culture can be used as a reactive gliosis model in vitro for studying GFAP expression of astrocytes.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.4
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• pp.299-307
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• 2011

The offshore plants such as FPSO are subjected to combination loading of environmental conditions (swell, wave, wind and current). Therefore the fatigue damage is occurred in the operation time because the units encounter the environmental phenomena and the structural configurations are complicated. This paper is a research for frequency domain fatigue analysis of wide-band random loading focused on accuracy of fatigue damage estimation regarding the proposed methods. We selected ideal bi-modal spectrum. And comparison between time-domain fatigue analysis and frequency-domain fatigue analyses are conducted through the fatigue damage ratio. Fatigue damage ratios according to Vanmarcke's bandwidth parameter are founded for wide-band. Considering safety, we recommend that Jiao-Moan and Tovo-Benasciutti methods are optimal way at the fatigue design for wide-band response. But, it is important that these methods based on frequency-domain unstably change the accuracy according to the material parameter of S-N curve. This study will be background and guidance for the new frequency-domain fatigue analysis development in the future.

• Journal of the Korean Society of School Health
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• v.9 no.2
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• pp.249-266
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• 1996

AIDS and the spectrum of Human Immunodeficiency Virus(HIV) infections present a monumental challenge to the health of the Korean public. In response to this special challenge, I think public education and voluntary behavior changes are the most effective measures to fight the spread of the disease. Adolescents represent a critical risk group for prevention and intervention programming. Research indicates sexually active adolescents, homosexual contact, illicit drug use are an gradually increasing. These characteristically adolescent risk-taking behaviors suggest the need for schools and communities to mobilize intervention strategies. Schools are highly efficient ways to reach a majority of young people in Korea with HIV prevention programs. These programs include substantial attention to sexual and drug use behaviors with the long term objective of a multidimensional school health program. Information resulting from risk behavior surveillance activities and guidance on school health curricula is particularly useful. What is needed for adolescents is a revamping of education to give students the critical thinking and analytic skills that allow them to apply knowledge, make decisions, and think independently. The best HIV preventive education provides young people with opportunities to learn and practice just those skills. In the early stages of HIV education were focused solely on information. Providing information is easy but unfortunately, behavior change is not that simple to activate. Information must be combined with values exploration and skilly building, including responsible decision making, negotiation, refusal, and critical thinking skills. The same knowledge, attitudes and skills needed for effective HIV prevention also prevent or reduce other risks, including other sexually transmitted diseases, unwanted pregnancies, and alcohol or other drug use. The role of other youth serving organizations in HIV prevention is also important: parental and youth involvement is needed; it's important to presidential and governament leadership is essential to prevention education; promote integrated adolescent programs, to enhance health and education sector collaboration; and of course, we need to expand research on adolescent health and engage the media in health promotion. Among these changes, a school-based systematic health education of AIDS is certainly one of the essentials.

• Korean Journal of Computational Design and Engineering
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• v.15 no.6
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• pp.425-439
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• 2010

The current challenge with which most shipyards are forced is to reduce the design time and the time-to-delivery because of explosive order of shipbuilding. Collaborative design and product data management have become important to reduce the lead time. Furthermore, enterprise information technologies such as ERP (Enterprise Resource Planning), SCM (Supply Chain management), and APS (Advanced Planning System) requires the collaborative environment. Also, manufacturing environment has been considered as a topic of strategic interest to get shorter product lifecycles in shipyards. Most shipyards have chosen an environment of ETO (Engineering To Order) strategy which designs and produces new products in response to various requirements of customer, rules and regulations. In the ATO (Assemble 10 Order) environment, most component parts have been designed to be procured or produced on the order requirement. The basic distinction between the ETO and ATO is the timing of the design. Thus in the ATO environment, it is more flexible in reducing the lead time to meet the specified requirements of customers. However, the ETO strategy requires new ship design process and ship product structures that are linked with the implementation of PLM. And, the function and architecture of current PLM solution has been designed based upon ATO environment properly. This paper presents the PLM architecture which effectively reflects the characteristics of shipbuilding. 4-layer architecture model is suggested to implement the PLM system. Also, implemented functions of ship PLM is explained in order to make a practical guidance for ship PLM implementation.

• Smart Structures and Systems
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• v.15 no.3
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• pp.717-733
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• 2015

Modal parameters of a structure are commonly used quantities for system identification and damage detection. With a limited number of studies on the statistics assessment of modal parameters, this paper presents procedures to properly account for the uncertainties present in the process of extracting modal parameters. Particularly, this paper focuses on how to deal with the measurement error in an ambient vibration test and the modeling error resulting from a modal parameter extraction process. A bootstrap approach is adopted, when an ensemble of a limited number of noised time-history response recordings is available. To estimate the modeling error associated with the extraction process, a model prediction expansion approach is adopted where the modeling error is considered as an "adjustment" to the prediction obtained from the extraction process. The proposed procedures can be further incorporated into the probabilistic analysis of applications where the modal parameters are used. This study considers the effects of the measurement and modeling errors and can provide guidance in allocating resources to improve the estimation accuracy of the modal data. As an illustration, the proposed procedures are applied to extract the modal data of a damaged beam, and the extracted modal data are used to detect potential damage locations using a damage detection method. It is shown that the variability in the modal parameters can be considered to be quite low due to the measurement and modeling errors; however, this low variability has a significant impact on the damage detection results for the studied beam.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.5
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• pp.225-230
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• 2008

Netrins are secreted molecules and involved in axon guidance, cell migration and tumor development. Recent studies revealed that netrins perform novel functions in such processes as epithelial development and angiogenesis without operating through the classical netrin receptors, DCC (Deleted in Colorectal Cancer) and Unc5h. In the present study, we investigated the roles of netrin-1 and its receptors in cell spreading of human glioblastoma cells, and found that netrin-1 haptotactically enhanced fibronectin-induced cell spreading and focal adhesion formation in U373 glioblastoma cells. Netrin-1 binding to the U373 cell membrane was blocked by an antibody against ${\alpha}v$ integrin subunit, but not by an anti-DCC or anti-Unc5h antibody. In addition, enhancement of the fibronectin response by netrin-1 was abrogated by a function blocking antibody against integrin ${\alpha}v{\beta}3$. Since the ${\alpha}v$ subunit of the integrin family plays an important role in the pathophysiological aspects of cell migration, including tumor angiogenesis and metastasis, our data provide important insight into the molecular mechanism of netrin function.

• Neonatal Medicine
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• v.15 no.1
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• pp.105-110
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• 2008

Neonatal liver abscesses are rare, carry a high mortality rate, and are difficult to diagnose. The diagnosis of liver abscesses in the neonate cannot be established from the clinical presentation alone. Risk factors for liver abscesses in neonates are maternal infection, sepsis, umbilical venous catheterization, omphalitis, and necrotizing enterocolitis. In this report, we describe a preterm infant (32 weeks, 1,580 g) who presented with abdominal distension, respiratory difficulties, and a persistent inflammatory response in spite of broad spectrum antibiotic treatment; a large (6${\times}$5 cm) solitary pyogenic liver abscess was identified at 9 days of age. It appeared that the liver abscess had originated in the uterus and umbilical venous catheterization facilitated its spread. Percutaneous drainage under abdominal ultrasound guidance was performed and prolonged antibiotics were treated for 5 weeks, effecting a cure.