• Journal of Oral Medicine and Pain
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• v.30 no.1
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• pp.131-140
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• 2005

The purpose of this study was to examine the ablation rate of Er: YAG laser irradiation on dentin and enamel and to observe the microscopic structures of cavities formed after ablation of enamel and dentin in using a bur and cavities formed after ablation using laser. Er:YAG laser irradiated at 200 mJ, 250mJ, 300mJ at the frequency of 20Hz, 15Hz. The following results were obtained : 1. The ablation rate of dentin groups at power of 3 W-6 W was about $1.103{\sim}2.639mm^3/sec$ and there were no significant differences between power of 4.5 W$\sim$6 W. 2. The ablation rate of enamel groups at power of 3 W-6 W was about $0.413{\sim}0.969mm^3/sec$ and there were no significant differences between power of 4 W$\sim$6 W. 3. With SEM examination of the cavity surface treated with the conventional high speed bur revealed relatively flat appearance almost covered with a debris like smear layer. 4. With SEM examination of the lased surface of dentin groups revealed no smear layer and no debris and openings of dentinal tubules were clearly opened. But the lased surfaces of the groups over 3 W were irregular and particles were loosely attached on it. 5. With SEM examination of the lased surface of enamel groups revealed severely destructed surface at the 6 W group and melting drop materials at the 3 W group. But the lased surface of 4 W group revealed clearly ablated surface. Therefore when cutting teeth using Er:YAG laser, the lasing power which can make effective ablation rate and minimize the thermal effect could be 3W at dentin and 4W at enamel. But, further studies and additional data collection will be necessary for appropriate lasing condition of Er:YAG laser.

• Journal of The Korean Association of Information Education
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• v.19 no.2
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• pp.215-224
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• 2015

For this, 410 development topics and contents were selected based on the analysis of contents related to mathematics and science, the pre-investigation and analysis of mathematics and science teachers in agricultural, mountain and fishing villages and the analysis of the 2009 revised curriculum. The validity verification of the selected subject list and implementation plan was implemented through the reviews by experts in each subject and the storyboard was designed by reflecting the examination opinion after the final revision. Development directions of the contents were set after analyzing the application result of contents from classroom for creativity and science and selected schools in agricultural, mountain and fishing villages for demonstration, and opened the platform after the revision and supplement of the expert. It is expected to elevate students' self-directed learning abilities in agricultural, mountain and fishing villages by developing and extending smart learning contents to use ICT in Mathematics and science education, which are high in urbanrural academic disparity.

• Journal of Chest Surgery
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• v.38 no.10 s.255
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• pp.721-724
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• 2005

Aortocaval fistula is a rare complication of abdominal aortic aneurysm, involving less than $1\%$ of all abdominal aortic aneurysms. A 64-years old man with a long history of hypertension and abdominal aortic aneurysm had chest pain, dyspnea, epigastric discomfort and palpable abdominal pulsating mass. Physical examination revealed hypo­tension with a systolic blood pressure of 70 mmHg, a large pulsatile mass and a systolic abdominal bruit. Laboratory data revealed a hemoglobin values of 11.0 g/dL, blood urea nitrogen (BUN) value of 5 mg/dL, and creatine value of $2.5 mg\%$. Abdominal Angio CT showed a 10cm infrarenal abdominal aortic aneurysm with dilatation of the IVC and aortocaval fistula from the aortic aneurysm, which was confirmed at emergency surgery. When the aneurysm was opened and the thrombus was removed, a 1 cm communication was identified between the aorta and IVC. This was controlled with Foley catheters ballooning, and the fistula was closed by continuous suture placed outside the aneurysm. A bifurcated aorto-iliac graft was used to restore arterial continuity. The patient was discharged home after uncomplicated postoperative course.

• Journal of Chest Surgery
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• v.38 no.10 s.255
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• pp.717-720
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• 2005

Here we report a case of posterior left ventricular (LV) free wall rupture following postinfarct ventricular septal rupture (VSR). A 58-year-old man was transferred to the hospital under the impression of acute myocardial infarction. Posterior VSR was seen on echocardiographic examination. The intraaortic balloon pump catheter was introduced percutaneously and the emergent operation was proposed. Sudden circulatory collapse was developed shortly after the anesthetic induction and the patient's chest was hurriedly opened while on cardiopulmonary resuscitation. The acute cardiac tamponade was seen and the blood was seen pumping from the longitudinal tear at the mid-level of LV posterior wall, measuring 2 cm in length. The cardiopulmonary bypass was set and LV reconstruction was done. The postoperative recovery was delayed due to the brain injury presumably caused by preoperative cardiac arrest.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6691-6696
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• 2015

Background: Endometrial carcinoma is the most common gynecological cancer and its treatment is still controversial, especially in its early stages. There are conflicting data about the efficacy of retroperitoneal lymphadenectomy during abdominal hysterectomy and bilateral salpingoophrectomy treatment. Lymphadenectomy carries a risk of severe complications, especially in women with co-morbidities. Selective lymphadenectomy has been widely employed for staging evaluation of endometrial carcinoma because it is simple and seems to provide reliable data regarding nodal metastasis. This study was designed to evaluate accuracy of sentinel node sampling in detecting lymph node metastasis in primary endometrial carcinoma during staging laparotomy. Materials and Methods: Ninety-three women with endometrial carcinoma at high-risk for nodal metastasis were studied. During laparotomy, methylene blue dye was injected into sub-serosal myometrium, then retroperitoneal spaces were opened and blue lymph nodes within pelvic and para-aortic regions were removed as separate specimens for histopathological examination (sentinel lymph nodes = SLNs). Hysterectomy and selective lymphadenectomy then performed for all women included in this study. Results: Deposition of methylene dye into at least one lymph node was observed in 73.1% (68/93) of studied cases. 18.3% (17/93) of studied women had positive lymph node metastasis and 94.1% (16/17) of them had positive metastasis in SLNs. In this study, SNLs had 94.4% sensitivity and 100% specificity in prediction of lymph node metastasis. Mean number of lymph nodes removed from each case decreased when SLNs biopsy were taken. Conclusions: SLNs are the key lymph nodes in endometrial tumor metastasis and their involvement could be an indicator for whether or not complete systematic lymphadenectomy is needed during staging laparotomy.

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.61-75
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• 1997

The bond strengths of composite resin to tooth dentin vary with the methods of cavity preparation and surface treatment. Recent developments in techniques of dentinal surface treatment have renewed interest in microabrasive as a means of tooth preparation, The purpose of this study was to determine the effects of a new method of cavity preparation on the bond of composite resin to dentin. Freshly extracted 144 healthy human third molars were used in this study. The dentin surfaces prepared with #600 SiC abrasive paper were divided into control and air abrasion groups according to the method of dentin surface preparation using different combinations of delivery pressure, time, and acid etching. The shear bond strengths were measured after the composite resin (Clearfil Photo Bright) was bonded to prepared dentin surfaces by light-curing using a dentin bonding system (All-bond 2), In addition, the average surface roughness was measured to investigate the effect of differently prepared dentin surfaces on the shear bond strengths. The surface changes of prepared dentin and the debonded dentin surfaces were observed with SEM (S-2300, Hitachi Co., Japan). The following results from this-study were obtained ; 1. There was no significant difference of shear bond strengths according to the changes of delivery pressure and time. 2. The shear bond strengths were lower than the control in the air abraded-only groups, but those of the additional acid-etched groups were higher than the control. 3. The shear bond strengths to all air-abraded surfaces were increased by acid etching. 4. The correlation between shear bond strengths and surface roughness was not certain, although the mean surface roughness of all air-abraded surfaces has increased evidently while it has slightly decreased for additional acid etching. 5. On SEM examination, the dentinal tubules were almost occluded in the air abraded-only groups, but those were opened in the additional acid-etched groups. 6. The debonded surfaces were showed adhesive failure mode in the air abraded- only groups, while those were showed mainly the mixed and cohesive failure mode in the additional acid-etched groups. These results suggest that the layer produced during cavity preparation or surface treatment with air abrasion must be removed for maximum bond strength of composite resin to dentin.

• Journal of the Korean Society of Costume
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• v.57 no.7
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• pp.30-44
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• 2007

The culture includes every possible objective forms created by humans and their shared aspects of ideas, feelings, and behaviors, beliefs and etc. The dress and its ornaments are part of the culture that expresses the relationships in objective ways and in formless immaterial ways. The school uniform represents significant meanings to the students in their school years, and it is the way of expressing their individuality and full filling their needs for self-presentation. Therefore, understanding and analyzing youth culture means understanding students' school uniform along with fast changing twenty first century civilization. Korea and Japan are very close nations to each other. Both Korean and Japanese girls' school uniform style were adopted western clothing style and went through many changes based on cultural differences between two countries. They are affected by different peculiarities between two nations and youth cultures from different cities. Therefore, this research is on analyzing how different visual values of girl's high school uniforms in Seoul and Tokyo and understanding youth cultures through macro-analysis. The youth cultures in Korea and Japan are mostly similar but there is special development on animation in Japan and possibly can find many styles of girl's high school uniform. Both nations are varying to be opened to sexual culture of adolescents but Japan is more uninhibited than Korea. In Japan, sailor-uniform can be found in fetish way in public culture. On one hand, because of most private girl's high schools in Tokyo takes an entrance examination, top-ranking students are very proud of their school uniforms and even students from other public high schools get private high school uniforms to attend school festival. This analysis showed that private girl's high school uniform in Seoul appealed as slim fitted silhouette which is close to modem woman's suit style while in Tokyo appealed as boxy style matched with short pleated skirt or sailor-uniform style. Comparing that to school uniform photos taken on the street, we can find that alikeness or more extreme styles as examples. These are influenced by different youth cultures in Seoul and Tokyo and cultural differences stands for different aesthetic norm being accepted or rejected.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.683-693
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• 2001

The purpose of this study was to evaluate the effects of Er:YAG laser on cutting efficacy and its histologic findings. Dentin specimens of human premolars and molars were used and irradiated by Er:YAG laser with noncontact handpiece type delivery system under different treatment condition of irradiation time. Cavity pattern and volume were evaluated to determine the cutting efficacy and following results were obtained. 1. Cutting volume of sound dentin was getting larger with time immersed in water increase 2. With the condition of irradiation (150mJ, 10Hz, 30sec), surface irregularity was more increased in sound dentin comparing to carious dentin. For the light microscopic examination, dentinal tubules were opened and ash flecks and cracks were noted with inconsistence of dentinal tubules. 3. In case of 30 sec. irradiation in carious dentin, dark zone was limited to small focus whereas 1 min. irradiation, more wider, and cracks were noted in the perpendicular to direction of dentinal tubules. For the 2 min. irradiation, cavity was the widest and more cracks were found.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.6
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• pp.89-100
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• 2014

The Campus Core is centered at the physical, functional and symbolic environment of a university, which is known as the top academic institution, hence it metaphorically represents not only the educational philosophy when institution first opened, but also the transformed values of the time. Today, universities are asked to actively communicate with the local community in terms of function and be remodeled as pedestrian-friendly campuses in terms of physical environment. For this reason, the study comprehends the concept of the campus core in accordance with a pedestrian-friendly environment and suggests a practical plan for campus cores of district national universities based on previous research examination. Since the purpose of the study is to suggest a change in the circulation system centered on vehicle use to transform into a pedestrian-friendly environment through a planned approach while introducing public mixed-use at the same time, the study supports the fact that it is possible to reorganize the strategy of a pedestrian-friendly circulation system and partially revise the land utilization to yield the expected outcomes. Thus, this study will provide valid suggestions for similar maintenance plans while looking back to the meaning and value of today's campus core.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.3
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• pp.327-331
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• 2011

Purpose: The purpose of this study was an accurate grasp of the astigmatic change due to eyes accommodation on near vision and suggested problems occurring accommodative astigmatism using near glasses. Methods: 154 subjects(308eyes) from 20 to 40 years selected for this study who had many opportunity of near vision. First, far vision corrective refraction measured using the phoropter, and then both eyes opened simultaneously for maintaining the function of binocular put away dot chart 40 cm. One eye was fogging and the other eye measured near vision astigmatism axis and degrees astigmatism using cross cylinder, and then compared with far astigmatism. Results: Increased degree of astigmatism persons on near vision more than decreased or did not changed degree of astigmatism persons, which could affect visual acuity more than 0.75 diopters in 30 eyes with an increase of 9.7% of total subjects. Direct astigmatism and oblique astigmatism were increased on near vision. Astigmatic axes were rotated base in direction on both eyes and 66.9% of subjects were more than ${\pm}$5$^{\circ}$ rotation. Due to the rotation axis of astigmatism, residual astigmatism is expected to occur and expect to adversely affect the eyes. Conclusions: Long-term using the glasses without correction of increased astigmatic and rotated axis on near vision should occur new residual astigmatism and increase the asthenopia also. Considered to be taken astigmatic change on near vision during near refraction examination.