• Imaging Science in Dentistry
• /
• v.45 no.4
• /
• pp.205-211
• /
• 2015

Purpose: This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Materials and Methods: Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this study. The specimens were classified into three groups: maxillary molars, mandibular molars with three canals, and mandibular molars with four canals. Differences between the gold standard and the observations made using the imaging methods were calculated using Spearman's rho correlation coefficient test. Results: The presence of accessory canals in micro-CT images of maxillary and mandibular root canals showed a statistically significant correlation with the stereomicroscopic images used as a gold standard. No statistically significant correlation was found between the CBCT findings and the stereomicroscopic images. Conclusion: Although micro-CT is not suitable for clinical use, it provides more detailed information about minor anatomical structures. However, CBCT is convenient for clinical use but may not be capable of adequately analyzing the internal anatomy of primary teeth.

• Advances in pediatric surgery
• /
• v.13 no.2
• /
• pp.105-111
• /
• 2007

We reviewed the records of 25 patients who were re-operated upon after primary repair of esophageal atresia with or without fistula at the Department of Pediatric Surgery, Seoul National University Children's Hospital, from January 1997 to March 2007. Types of the esophageal atresia anomalies were Gross type A in 5 patients, C in 18, and E in 2. The indications for re-operation were anastomosis stricture (n = 14), tracheo-bronchial remnant (n = 4), persistent anastomosis leakage (n = 3), recurrent tracheo-esophageal fistula (n = 2) and esophageal web (n = 2). The interval between primary and secondary surgery was from 48 days to 26 years 5 months (mean: 2 years and 4 months). Four patients required a third operation. The interval between the second and third operation was between 1 year 1 month and 3 year 10 month (mean: 2 years 5 months). Mean follow up period after last operation was 35 months (1 years-8 years 6 months). The secondary surgery was end-to-end esophageal anastomosis in 15, esophagoplasty in 5, gastric tube replacement in 5. After secondary operation, 6 patients had anastomosis stricture (4 patients were relieved of the symptoms by balloon dilatation, 2 patients underwent tertiary operation). Five patients had leakage (sealed on conservative management in all). Two patients had recurrent tracheo-esophagel fistula (1 patient received chemical cauterization and 1 patient underwent tertiary operation). Currently, only one patient has feeding problems. There were no mortalities. Secondary esophageal surgery after primary surgery for esophageal atresia was effective and safe, should be positively considered when complications do not respond to nonoperative therapy.

• 사회경제평론
• /
• v.31 no.3
• /
• pp.239-270
• /
• 2018

This study empirically analyzed the labor income share of primary and subcontractors. The results are as follows. First, panel regression analysis showed that the variables of transaction concentration, outsourcing cost, capital intensity, and market share had a significant negative effect, while union organization rate and R & D investment had positive effects. In particular, the R & D variable had a negative effect on the share of labor income in the year of investment (t), but had a positive impact on the long-term (t-1, t-2). Second, the share of labor income during the last 11 years (2006~2016) was higher in subcontractors with lower wage levels. This analysis implies that the wage inequality between the primary and subcontracting enterprises can not be eliminated without improving the solvency of subcontractors.

• Journal of Chest Surgery
• /
• v.26 no.4
• /
• pp.329-332
• /
• 1993

Breakdown of the normal protective function of the larynx, either through primary or neurologic cause, leads to chronic aspiration, recurrent pneumonitis and possibly death. Lindemann`s tracheoesophageal diversion has three main advantages; first, it eliminates intractable aspiration in all patients who underwent the procedure, second, it preserves larynx, and third, if the underlying neurologic condition is recorved, the procedure can be reversed. We had performed tracheoesophageal diversion in two cases of intractable aspiration pneumonia patients. The postoperative courses were uneventful and they were receiving oral alimentation on the 22th and 9th postoperative days respectively, and could be discharged on 43th and 20th postoperative days respectively.

• Korean Management Science Review
• /
• v.12 no.2
• /
• pp.63-75
• /
• 1995

The uncapacitated facility location problem considered here is to determine facility location sites, minimizing the total cost of establishing facilities and serving customer demand points which require primary and back-up services. To solve this problem effectively, we propose two things in this study. First, we propose an idea of Benders' decomposition approach as a solution method of the problem. Second, we implement the problem on GAMS. Using GAMS (general Algebraic Modeling System) can utilize an mixed-integer programming solver such as ZOOM/XMP and provide a completely general automated implementation with a proposed solution method.

• Journal of Chest Surgery
• /
• v.20 no.2
• /
• pp.399-403
• /
• 1987

Ewing`s sarcoma is a highly malignant tumor which occurs most frequently in the diaphysis of the long bones, although any bone may be involved. Ewing`s sarcomas occurring in the rib are rare. Recently, we experienced one case of Ewing`s sarcoma which arose in the right second rib in a young female patient. She was treated with three principal treatment modalities-en bloc excision of chest wall followed by radiation therapy and chemotherapy. Clinical course is described with review of related literatures.

• Journal of Chest Surgery
• /
• v.25 no.11
• /
• pp.1261-1263
• /
• 1992

Primary cardiac fibroma of the left ventricular myocardium is a rare tumor of the heart which is usually located within the anterior wall and /or septum of the left ventricle and is the second most common cardiac tumor in infant and children. Although the tumor is benign histologically, it may cause severe cardiac dysfunction and sudden death. A 30-day-old neonate with a huge intramural fibroma involving the posterolateral wall of the left ventricle underwent it`s partial resection under extracorporeal circulation on April 1992.

• Journal of Chest Surgery
• /
• v.12 no.2
• /
• pp.97-100
• /
• 1979

Primary intrathoracic neoplasms occur frequently, and the most frequent intrathoracic tumors are of pulmonary or bronchogenic origin. Second in frequency are mediastinal tumors, and least frequency or comparatively rare are the neoplasms arising from the wall of the thorax and extending into the thoracic cavity. Of all intrathoracic tumors, fibroma is extremely rare. Recently, we have experienced a huge rapid growing intrathoracic fibroma originating from thoracic wall, which is removed successfully and confirmed histopathologically. Authors present one case of fibroma and discussion with a brief review of the relevant literatures.

• Education of Primary School Mathematics
• /
• v.7 no.2
• /
• pp.75-84
• /
• 2003

The purpose of this study is to suggest the direction for development of function materials integrating mathematics and science. First, we must investigate curricular scope and sequence of mathematics and science. Second, the science contexts selected need to support the mathematics concepts, not overwhelm them. The mathematics can easily get lost if science becomes too complicated. We may be tempted, which can result in misconceptions that are hard to correct later. Third, Many different examples of mathematics-science integration exist, therefore, it is important to find rich science contexts to connect with mathematics.

• KSBB Journal
• /
• v.8 no.1
• /
• pp.1-9
• /
• 1993

The acetone-butanol fermentation by C. acetobutylicum has gained increasing attention for the following reasons. First, the finite supply of petrochemical resources, combined with increasing concern over global environmental effects and the unstable nature of the price of petroleum has renewed interest in the development of fermentation technology that allows utilzation of biomass wastes for the production of alcohol. Second, it serves as excellent model system for understading the regulation and molecular biology of tightly regulated complex primary metabolism, and for applications of metabolic engineering. In this review various aspects of acetone-butanol fermentation by C. acetobutylicm including strain and fermentation characteristics, enzyme regulation, and solvent formation mechanism, and product recovery and summarized.