• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.308-315
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• 2011

Purpose: The purpose of this study was to colorimetrically evaluate the masking effect of different opacity of ingots on the final shade of IPS Empress Esthetic$^{(R)}$ laminate veneer restorations using the CIE $L^*a^*b^*$ system. Materials and methods: Six porcelain disks of IPS Empress Esthetic$^{(R)}$ system (translucency: E 01, E 03, E 0C-1, E TC-1, E TC-2, E TC-3) were fabricated with 7 mm in diameter and 0.6 mm in thickness. Six extracted human incisors (shade: A1, A3, A4, B2, B3, C3) were used as the abutment specimens. The incisors were prepared using a diamond wheel and made with a flat labial surface on the middle 1/3. For each combination of different shades of abutments and copings, the change in color was measured with a colorimeter. CIE $L^*a^*b^*$ coordinates were recorded for each specimen. Color differences (${\Delta}E$) were calculated. Descriptive statistical analysis was done. Results: ${\Delta}E$ values were significantly affected by coping translucency and abutment shade (P<.05). The color differences (${\Delta}E$) of laminate veneers among abutments with A3, B3, C3, and A4 shade were mostly below 2.7 which was within the clinically acceptable range, while color differences between A4 and B2, A3 and B2, and A1 and A4 showed more than 2.7. Conclusion: The final color of IPS Empress Esthetic$^{(R)}$ laminate veneers were significantly influenced by translucency of the coping and shade of abutment teeth. The large value difference of abutment teeth limited the masking ability by laminate veneers.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.300-304
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• 2007

The purpose of this study was to determine the anesthetic effects of tiletamine-zolazepam (TZ) alone and azaperone plus tiletamine-zolazepam in growing pigs, and to compare the various physiological parameters in both treatments. Cross experiment was accomplished at 2-week interval. Group 1 (TZ group): six pigs ($31.4{\pm}4.83$ kg) received 4.4 mg/kg of TZ alone. Group 2 (ATZ group); the same six pigs ($43.6{\pm}4.31$ kg) received 4.4 mg/kg of TZ twenty minutes after receiving 2 mg/kg of azaperone. All of the anesthetic drugs were injected into the trapezius muscles. The pigs were fasted for 24 hours before the experiments. Induction and recovery values were determined. Heart rate, respiratory rate, rectal temperature, $pO_2,\;pCO_2$ and pH were determined before administration and 5, 25, 45, 65 and 85 minutes after administration. Induction time of ATZ group was more rapid than that of TZ group (p<0.01). During recovery, sternal recumbency time, standing time and walking time of ATZ group were longer than those of TZ group (p<0.01). Heart rate, respiratory rate, $pO_2,\;pCO_2$, and pH did not show especial differences between the two groups. However, rectal temperature was significantly different between the TZ and ATZ group (p<0.05). As a result, ATZ group had a faster induction and a longer duration of anesthesia than TZ group did. Thus, it was concluded that ATZ combination could be usefully used for chemical restraint in pigs.

• Journal of Korean Neurosurgical Society
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• v.30 no.7
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• pp.883-890
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• 2001

Objectives : An in vitro biomechanical study of posterior lumbar interbody fusion(PLIF) with threaded cage using two different approaches was performed on eighteen functional spinal units of bovine lumbar spines. The purpose of this study was to compare the segmental stiffnesses among PLIF with one long posterolateral cage, PLIF with one long posterolateral cage and simultaneous facet joint fixation, and PLIF with two posterior cages. Methods : Eighteen bovine lumbar functional spinal units were divided into three groups. All specimens were tested intact and with cage insertion. Group 1(n=12) had a long threaded cage($15{\times}36mm$) inserted posterolaterally and oriented counter anterolaterally on the left side by posterior approach with left unilateral facetectomy. Group 2(n=6) had two regular length cages($15{\times}24mm$) inserted posteriorly with bilateral facetectomy. Six specimens from group 1 were then retested after unilateral facet joint screw fixation in neutral(group 3). Likewise, the other six specimens from group 1 were retested after fixation with a facet joint screw in an extended position(group 4). Nondestructive tests were performed in pure compression, flexion, extension, lateral bending, and torsion. Results : PLIF with a single cage, group 1, had a significantly higher stiffnesses than PLIF with two cages, group 2, in left and right torsion(p<0.05). Group 1 showed higher stiffness values than group 2 in pure compression, flexion, left and right bending but were not significantly different. Group 3 showed a significant increase in stiffness in comparison to group 1 for pure compression, extension, left bending and right torsion(p<0.05). For group 4, the stiffness significantly increased in comparison to group 1 for extension, flexion and right torsion(p<0.05). Although there was no significant difference between groups 3 and 4, group 4 had increased stiffness in extension, flexion, right bending and torsion. Conclusion : Posterior lumbar interbody fusion with a single long threaded cage inserted posterolaterally with unilateral facetectomy enables sufficient decompression while maintaining a majority of the posterior elements. In combination with a facet joint screw fixation, adequate postoperative stability can be achieved. We suggest that posterolateral insertion of a long threaded cage is biomechanically an ideal alternative to PLIF.

• Journal of Intelligence and Information Systems
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• v.29 no.3
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• pp.361-381
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• 2023

Research on corporate bankruptcy prediction has been focused on financial information. Since the company's financial information is updated quarterly, there is a problem that timeliness is insufficient in predicting the possibility of a company's business closure in real time. Evaluated companies that want to improve this need a method of judging the soundness of a company that uses information other than financial information to judge the soundness of a target company. To this end, as information technology has made it easier to collect non-financial information about companies, research has been conducted to apply additional variables and various methodologies other than financial information to predict corporate bankruptcy. It has become an important research task to determine whether it has an effect. In this study, we examined the impact of electronic payment-related information, which constitutes non-financial information, when predicting the closure of business operators using electronic payment service and examined the difference in closure prediction accuracy according to the combination of financial and non-financial information. Specifically, three research models consisting of a financial information model, a non-financial information model, and a combined model were designed, and the closure prediction accuracy was confirmed with six algorithms including the Multi Layer Perceptron (MLP) algorithm. The model combining financial and non-financial information showed the highest prediction accuracy, followed by the non-financial information model and the financial information model in order. As for the prediction accuracy of business closure by algorithm, XGBoost showed the highest prediction accuracy among the six algorithms. As a result of examining the relative importance of a total of 87 variables used to predict business closure, it was confirmed that more than 70% of the top 20 variables that had a significant impact on the prediction of business closure were non-financial information. Through this, it was confirmed that electronic payment-related information of non-financial information is an important variable in predicting business closure, and the possibility of using non-financial information as an alternative to financial information was also examined. Based on this study, the importance of collecting and utilizing non-financial information as information that can predict business closure is recognized, and a plan to utilize it for corporate decision-making is also proposed.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.1
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• pp.16-37
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• 2018

In this study, difference in chemical composition of $PM_{2.5}$ observed between the year 2013 and 2015 at six air quality intensive monitoring stations (Bangryenogdo (BR), Seoul (SL), Daejeon (DJ), Gwangju (GJ), Ulsan (US), and Jeju (JJ)) was investigated and the possible factors causing their difference were also discussed. $PM_{2.5}$, organic and elemental carbon (OC and EC), and water-soluble ionic species concentrations were observed on a hourly basis in the six stations. The difference in chemical composition by regions was examined based on emissions of gaseous criteria pollutants (CO, $SO_2$, and $NO_2$), meteorological parameters (wind speed, temperature, and relative humidity), and origins and transport pathways of air masses. For the years 2013 and 2014, annual average $PM_{2.5}$ was in the order of SL ($${\sim_=}DJ$$)>GJ>BR>US>JJ, but the highest concentration in 2015 was found at DJ, following by GJ ($${\sim_=}SJ$$)>BR>US>JJ. Similar patterns were found in $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$. Lower $PM_{2.5}$ at SL than at DJ and GJ was resulted from low concentrations of secondary ionic species. Annual average concentrations of OC and EC by regions had no big difference among the years, but their patterns were distinct from the $PM_{2.5}$, $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ concentrations by regions. 4-day air mass backward trajectory calculations indicated that in the event of daily average $PM_{2.5}$ exceeding the monthly average values, >70% of the air masses reaching the all stations were coming from northeastern Chinese polluted regions, indicating the long-range transportation (LTP) was an important contributor to $PM_{2.5}$ and its chemical composition at the stations. Lower concentrations of secondary ionic species and $PM_{2.5}$ at SL in 2015 than those at DJ and GJ sites were due to the decrease in impact by LTP from polluted Chinese regions, rather than the difference in local emissions of criteria gas pollutants ($SO_2$, $NO_2$, and $NH_3$) among the SL, DJ, and GJ sites. The difference in annual average $SO{_4}^{2-}$ by regions was resulted from combination of the difference in local $SO_2$ emissions and chemical conversion of $SO_2$ to $SO{_4}^{2-}$, and LTP from China. However, the $SO{_4}^{2-}$ at the sites were more influenced by LTP than the formation by chemical transformation of locally emitted $SO_2$. The $NO_3{^-}$ increase was closely associated with the increase in local emissions of nitrogen oxides at four urban sites except for the BR and JJ, as well as the LTP with a small contribution. Among the meterological parameters (wind speed, temperature, and relative humidity), the ambient temperature was most important factor to control the variation of $PM_{2.5}$ and its major chemical components concentrations. In other words, as the average temperature increases, the $PM_{2.5}$, OC, EC, and $NO_3{^-}$ concentrations showed a decreasing tendency, especially with a prominent feature in $NO_3{^-}$. Results from a case study that examined the $PM_{2.5}$ and its major chemical data observed between February 19 and March 2, 2014 at the all stations suggest that ambient $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations are not necessarily proportional to the concentrations of their precursor emissions because the rates at which they form and their gas/particle partitioning may be controlled by factors (e.g., long range transportation) other than the concentration of the precursor gases.

• Radiation Oncology Journal
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• v.27 no.2
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• pp.71-77
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• 2009

Purpose: We investigated the outcome and the prognostic factors of patients with locally advanced esophageal cancer who were treated with concurrent chemo-radiotherapy. Materials and Methods: Two hundred forty six patients with esophageal cancer that were treated by radiotherapy between January 1994 and July 2007. Of these, 78 patients who received radiotherapy of $\geq$45 Gy with concurrent chemotherapy were retrospectively enrolled in this study. We included patients stages IIA, IIB, III, IVA, and IVB with supraclavicular metastasis in the middle/lower esophageal cancer or celiac node metastasis in cervical or upper/middle thoracic esophageal cancer. The median radiation dose was 54 Gy and the combination chemotherapy with 5-FU and cisplatin (FP chemotherapy) was given concurrently with radiotherapy in most patients (88%). Results: The follow-up period ranged from 2 to 117 months (median 14 months). The treatment response of the 54 patients could be evaluated by computerized tomography or endoscopy. A complete response (CR) was observed in 17 patients, whereas a partial response was observed in 18 patients. In patients with a CR, the median recurrence time was 20 months and the first relapse sites constituted a locoregional failure in 3 patients and a distant failure in 7 patients. The 1-, 2-, and 5-year overall survival (OS) rates were 58.9%, 21.7%, and 12.2%, respectively. The median survival period was 14 months. A univariate analysis indicated that the treatment response and cycles of FP chemotherapy were significant prognostic factors for OS. Daily or weekly administration of cisplatin as a radiosensitizer showed a better treatment response than FP chemotherapy. Conclusion: This study has shown that results of concurrent chemo-radiotherapy in patients with locally advanced esophageal cancer is comparable to those of other studies. Daily or weekly cisplatin administration may be considered as an alternative treatment in patients that are medically unfit for FP chemotherapy.

• Clinical and Experimental Pediatrics
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• v.49 no.5
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• pp.552-557
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• 2006

Purpose : The recent results observed in precocious puberty and the hope that interrupting puberty might increase adult height have led to an attempt to use GnRH agonist(GnRHa) in children with premature puberty and a poor growth prognosis. We aimed to analyze the growth promoting effect of GnRHa in girls with early puberty and low predicted adult height(PAH). Methods : Thirty six girls were recruited. They were grouped according to the GnRHa treatment period(group 1>6 mo, n=18; group 2<6 mo, n=18). The following variables were analyzed before and after GnRHa treatment : chronological age(CA), bone age(BA), ${\Delta}age$(CA-BA), height, target height (TH), PAH, serum IGF-1, IGFBP-3. Results : Duration of the GnRHa treatment was $0.89{\pm}0.81yr$($1.37{\pm}0.92yr$ in group 1, and $0.41{\pm}0.08yr$ in group 2). Before treatment, none of the variables were different between the two groups. There were no differences in the following variables the between two groups at the end of treatment : CA, BA, ${\Delta}age$, PAH, serum IGF-1, IGFBP-3. But, growth velocity(GV) and PAH increment during treatment were significantly reduced in group 1. Compared with initial PAH, PAH at the end of treatment was significantly increased($3.7{\pm}3.2cm$). The last serum levels of IGF-1 and IGFBP-3 were lower than those before treatment. Conclusion : Even though last PAH didn't approach TH, short term GnRHa administration in early puberty with low predicted PAH was somewhat effective. But, GnRHa administration suppressed the growth hormone-IGF-1 axis. Therefore, it is recommended that growth hormone(GH) should be used in combination with GnRHa.

• Journal of Chest Surgery
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• v.31 no.8
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• pp.749-755
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• 1998

Background: Twelve patients with acyanotic tetralogy of Fallot(TOF), characterized by the combination of a malaligned ventricular septal defect(VSD) and infundibular pulmonic stenosis with the clinical finding of acyanosis at rest, underwent surgical correction between January 1988 and July 1997. Materials and methods: 9.92% of patients with the diagnosis of TOF were acyanotic TOF in the same period. Ages ranged from 12 to 42 months(mean 25.2 months). 2D-echocardiographic studies, cardiac catheterization, and angiocardiograms were performed in all patients before operation. The preoperative mean systemic arterial oxygen saturation was 93.5%. According to the 2D-echocardiographic analysis, there was Lt-to-Rt shunt through VSD in 4 patients, bidirectional shunt in 2 patients, and no shunt in 6 patients. Results: The preoperative mean right ventricle to pulmonary artery(RV-PA) pressure gradients were 52.3 mmHg on 2D- echocardiogram and 48.4 mmHg on cardiac catheterization. The repair of ventricular septal defect was performed through a right atrial approach and the hypertrophic infundibular muscle bundles were resected by the transatrial and transpulmonary approach. Six patients(50%) received a transannular patch. The mean cardiopulmonary bypass time was 135.0 minutes, and the aortic crossclamp time was 87.8 minutes. Postoperative complications included bleeding necessitating reentry in one and chylothorax in one. No patient died after operation and there were no late deaths. Postoperative 2D-echocardiograms revealed tiny patch dehiscence in 5 cases and a moderate RV-PA pressure gradients(mean 15.3 mmHg). All patients were in New York Heart Association functional class 1 after operation. Conclusions: acyanotic TOF is the uncommon form of TOF, and acyanotic TOF can be repaired with a good outcome.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.157-166
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• 2015

Purpose: The effects of water extract and distillate from the mixture of black goat meat and medicinal herb on MG-63 osteoblast proliferation and mouse bone marrow derived osteoclast formation were investigated. Methods: Proximate composition, volatile basic nitrogen (VBN), mineral content, free amino acid composition and free fatty acid composition in black goat meat were determined. Water extract and distillate were prepared with three groups; goat meat only (BG-E, BG-D), six herbs added group (BG-E6, BG-D6), and eight herbs added group (BG-E8, BG-D8). Osteoblast proliferation, mineralization and calcium uptake activity of MG-63 cells were measured and tartrate resistant acid phosphatase activity of osteoclasts was analyzed. Results: Black goat meat had remarkably low fat and high level of calcium. Glutamic acid was the most abundant amino acid. Herbs added extract groups (BG-E6 and BG-E8) showed increased MG-63 cell proliferation in a concentration dependent manner, while all the distillates did not show the effect. All extracts and distillates showed significantly increased osteoblast mineralization depending on the concentration. In particular, herb added extract, BG-E6, increased 170.3% of control and the distillate of BG-D and BG-D6 increased up to 168.5% and 159.8%, respectively. Calcium uptake activities of all water extracts showed remarkable increase of BG-E6 and BG-E8 up to 615.5% and 628.1% of control, respectively. Ditillates had no effect except BG-D6. All water extracts significantly reduced the activity of tartrate-resistant acid phosphatase (TRAP) in osteoclasts derived from mouse bone marrow. Conclusion: Combination of black goat meat and medicinal herb increased the MG-63 cell proliferation and effectively inhibited osteoclast differentiation in both water extracts and distillate of them, which implies that they could be used as potent functional food materials for bone health.

• Journal of the Korean earth science society
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• v.41 no.3
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• pp.248-260
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• 2020

Oceanic current maps introduced in science and earth science textbooks can offer a valuable opportunity for students to learn about rapid climate change and the role of currents associated with the global energy balance problem. Previously developed oceanic current maps in middle and high school textbooks under the 2007 and 2009-revised national curriculum contained various errors in terms of scientific accuracy. To resolve these problems, marine experts have constructed a unified oceanographic map of the oceans surrounding the Korean Peninsula. Since 2010, this process has involved a continuous, long-term consultation procedure. By extensively gathering opinions and through verification process, a representative and scientific oceanic current map was eventually constructed. Based on this, the educational oceanic current maps, targeting the comprehension of middle and high school students, were developed. These maps were incorporated into middle and high school textbooks in accordance with the revised 2015 curriculum. In this study, we analyzed the oceanic current maps of five middle school science textbooks and six earth science textbooks that were published in high school in 2019. Although all the oceanic current maps in the textbooks were unified based on the proposed scientific oceanic current maps, there were problems such as the omission of certain oceanic currents or the use of a combination of dotted and solid lines. Moreover, several textbooks were found to be using incorrect names for oceanic currents. This study suggests that oceanic current maps, produced by integrating scientific knowledge, should be visually accurate and utilized appropriately to avoid students' misconception.