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Diagnostic value of C-reactive Protein and Vascular Endothelial Growth Factor in Differentiation of Pleural Effusions (흉막액 감별에 있어서 C-반응성단백과 혈관내피성장인자의 유용성)

  • Kim, Sang Ha;Lee, Won Yeon;Park, Joo Young;Park, Hyun Sook;Han, Hye-Kyoung;Ju, Hun Su;Hong, Tae Won;Lee, Nak Won;Shin, Kye Chul;Yong, Suk Joong
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.5
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    • pp.467-477
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    • 2003
  • Background : Pleural effusions are generally divided into transudates and exudates. If it is exudative, more diagnostic tests are required in order to determine the cause of the local disease. A malignancy is a common and important cause of exudative pleural effusions. Because the pleural fluid cytology and pleural biopsy specimens do not provide a diagnosis in a high percentage of malignant effusions, several tumor markers have been examined. In order to overcome this limitation, this study hypothesized that C-reactive protein(CRP) and vascular endothelial growth factor(VEGF) measurements would be useful for differentiating trasudates from exudates and determining the differences between a benign and malignant effusion. Methods : Eighty consecutive patients with a pleural effusion (tuberculous 20, parapneumonic 20, malignant 20, transudative 20) were examined prospectively: 60 of them were classified according to Light's criteria as having an exudative fluid and 20 had a transudative fluid. The standard parameters of a pleural effusion were examined and the serum and pleural effusion VEGF levels were measured using enzyme linked immunosorbent assay(ELISA). CRP in the serum and pleural fluid was determined by a turbidimetric immunoassay. Results : The pleural CRP levels in the exudates were significantly higher than those in the transudates, $4.19{\pm}4.22mg/d{\ell}$ and $1.29{\pm}1.45mg/d{\ell}$, respectively. The VEGF levels in the pleural effusions were significantly elevated in the exudates compared to the transudate, $1,011{\pm}1,055pg/m{\ell}$ and $389{\pm}325pg/m{\ell}$, respectively. The VEGF ratio in the exudative effusion is significantly higher than a transudative effusions, $3.9{\pm}4.7$ and $1.6{\pm}0.9$, respectively. The pleural CRP levels in the patients with a benign effusion($4.15{\pm}4.20mg/d{\ell}$) were significantly higher than those in the malignant effusion($1.43{\pm}1.91mg/d{\ell}$). The VEGF ratio is significantly higher in malignant effusions($4.9{\pm}5.5$) than in benign effusions($2.8{\pm}3.6$). Conclusion : In conclusion, the CRP and VEGF levels in the serum and pleural effusion can distinguish between transudates and exudates. Moreover it can differentiate between benign and malignant pleural effusions.

Comparison of metal wire reinforcement and glass fiber reinforcement in repaired maxillary complete denture (상악 총의치 정중 파절 수리 시 금속선 및 유리섬유의 보강효과 비교)

  • Lee, Jung-Ie;Jo, Jae-Young;Yun, Mi-Jung;Jeon, Young-Chan;Jeong, Chang-Mo;Huh, Jung-Bo
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.4
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    • pp.284-291
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    • 2013
  • Purpose: This study compared fracture strength and fracture modes between metal wire reinforcement and glass fiber reinforcement in repaired maxillary complete denture. Materials and methods: In this study, fracture was reproduced on center of maxillary complete dentures and the denture was repaired with auto-polymerizing resin. The experimental groups (n = 10) were subjected to the following condition: without reinforcing material (control group), reinforcing with metal wire (W group), reinforcing with glass fiber pre-impregnated with light-curing resin (SES MESH, INNO Dental Co., Yeoncheon, Korea, G group). The fracture strength and fracture modes of a maxillary complete denture were tested using Instron test machine (Instron Co., Canton, MA, USA) at a 5.0 mm/min crosshead speed. The flexure load was applied to center of denture with a 20 mm diameter ball attachment. When fracture occurred, the fracture mode was classified based on fracture lines. The Kruskal-wallis test and the Mann-whitney U test were performed to identify statistical differences at ${\alpha}=.05$. Results: W group showed the highest value of fracture strength, there was no significant difference (P>.05) between control group and G group. Control group and W group showed anteroposterior fracture mainly, group W showed adhesive fracture of denture base and reinforcing material. Conclusion: In limitation of this study, the glass fiber did not improve the fracture strength of repaired maxillary complete denture, and adhesive failure was occurred along the lines of glass fiber.

EFFECTS OF VARIOUS CEMENTS AND THERMOCYCLING ON RETENTIVE STRENGTHS OF CEMENTED IMPLANT-SUPPORTED PROSTHESES (시멘트 유지형 임플란트 보철물의 유지력에 시멘트의 종류와 열순환이 미치는 영향에 관한 연구)

  • Cho Jae-Ho;Jeong Chang-Mo;Jeon Young-Chan
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.4
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    • pp.466-475
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    • 2003
  • Statement of problem : In cemented implant-supported porstheses, it is still controversy what kind of cement to use. However, the effect of thermocycling on retentive strength of cemented implant-supported prostheses has not been well investigated. Purpose : This study was tested to evaluate the effects of various cements and thermocycling on retentive strengths of cemented implant-supported prostheses. Material and methods : Prefabricated implant abutments, height 5mm, diameter 6mm, 3-degree taper per side, with light chamfer margins were used. Ten specimens of two-unit fred partial denture were fabricated. The luting agents used for this study were three provisional luting agents which were Temp bond, Temp bond NE, IRM and four permanent luting agents which were Panavia F, Fuji-cem, Hy-bond Zinc cement, Hy-bond Polycarboxylate cement. 24 hours after cementation. the retentive strengths were measured by the universal testing machine with a cross-head speed of 0.5mm/min. Then cementation procedures were repeated and specimens were thermocycled 1000 times at temperature of $5^{\circ}C$ and $55^{\circ}C$. After thermocycling, the retentive strengths were measured. Results : Before thermocycling, the retentive strengths were decreased with the sequence of Panavia F. Fuji-cem. Hy-bond Zinc cement. Hy-bond Polycarboxylate cement, IRM, Temp bond NE and Temp bond, and there were significant differences among each groups(p<0.05). After thermocycling, the retentive strengths were decreased with the sequence of Panavia F. Fuji-cem, Hybond Zinc cement, Hy-bond Polycarboxylate cement, IRM, Temp bond NE and Temp bond, and there were no significant differences among Panavia F, Fuji-cem and Temp bond NE, Temp bond(p>0.05). The retentive strengths before and after thermocycling showed significant differences in Hy-bond Zinc cement. IRM, Temp bond NE and Temp bond(p<0.05). Conclusion : Within the limitation of this study, thermocycling do not affect the retentive strengths of permanent luting agents but the retentive strengths of temporary cements were reduced significantly after thermocyling.

AFTL: An Efficient Adaptive Flash Translation Layer using Hot Data Identifier for NAND Flash Memory (AFTL: Hot Data 검출기를 이용한 적응형 플래시 전환 계층)

  • Yun, Hyun-Sik;Joo, Young-Do;Lee, Dong-Ho
    • Journal of KIISE:Computer Systems and Theory
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    • v.35 no.1
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    • pp.18-29
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    • 2008
  • NAND Flash memory has been growing popular storage device for the last years because of its low power consumption, fast access speed, shock resistance and light weight properties. However, it has the distinct characteristics such as erase-before-write architecture, asymmetric read/write/erase speed, and the limitation on the number of erasure per block. Due to these limitations, various Flash Translation Layers (FTLs) have been proposed to effectively use NAND flash memory. The systems that adopted the conventional FTL may result in severe performance degradation by the hot data which are frequently requested data for overwrite in the same logical address. In this paper, we propose a novel FTL algorithm called Adaptive Flash Translation Layer (AFTL) which uses sector mapping method for hot data and log-based block mapping method for cold data. Our system removes the redundant write operations and the erase operations by the separating hot data from cold data. Moreover, the read performance is enhanced according to sector translation that tends to use a few read operations. A series of experiments was organized to inspect the performance of the proposed method, and they show very impressive results.

A Study on Synthetic Techniques Utilizing Map of 3D Animation - A Case of Occlusion Properties (오클루전 맵(Occlusion Map)을 활용한 3D애니메이션 합성 기법 연구)

  • Park, Sung-Won
    • Cartoon and Animation Studies
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    • s.40
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    • pp.157-176
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    • 2015
  • This research describes render pass synthetic techniques required to use for the effectiveness of them in 3D animation synthetic technology. As the render pass is divided by property and synthesized after rendering, elaborate, rapid synthesis can be achieved. In particular, occlusion pass creates a screen as if it had a soft, light shading, expressing a sense of depth and boundary softness. It is converted into 2D image through a process of pass rendering of animation projects created in 3D space, then completed in synthetic software. Namely, 3D animation realizes the completeness of work originally planned through compositing, a synthetic process in the last half. To complete in-depth image, a scene manufactured in 3D software can be sent as a synthetic program by rendering the scene by layer and property. As recently the occlusion pass can express depth notwithstanding conducting GI rendering of 3D graphic outputs, it is an important synthetic map not omitted in the post-production process. Nonetheless, for the importance of it, currently the occlusion pass leaves much to be desired for research support and books summarizing and analyzing the characteristics of properties, and the principles and usages of them. Hence, this research was aimed to summarize the principles and usages of occlusion map, and analyze differences in the results of synthesis. Furthermore, it also summarized a process designating renderers and the map utilizing the properties, and synthetic software usages. For the future, it is hoped that effective and diverse latter expression techniques will be studied beyond the limitation of graphic expression based on trends diversifying technique development.

Construction and Experiment of an Educational Radar System (교육용 레이다 시스템의 제작 및 실험)

  • Ji, Younghun;Lee, Hoonyol
    • Korean Journal of Remote Sensing
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    • v.30 no.2
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    • pp.293-302
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    • 2014
  • Radar systems are used in remote sensing mainly as space-borne, airborne and ground-based Synthetic Aperture Radar (SAR), scatterometer and Doppler radar. Those systems are composed of expensive equipments and require expertise and professional skills for operation. Because of the limitation in getting experiences of the radar and SAR systems and its operations in ordinary universities and institutions, it is difficult to learn and exercise essential principles of radar hardware which are essential to understand and develop new application fields. To overcome those difficulties, in this paper, we present the construction and experiment of a low-cost educational radar system based on the blueprints of the MIT Cantenna system. The radar system was operated in three modes. Firstly, the velocity of moving cars was measured in Doppler radar mode. Secondly, the range of two moving targets were measured in radar mode with range resolution. Lastly, 2D images were constructed in GB-SAR mode to enhance the azimuth resolution. Additionally, we simulated the SAR raw data to compare Deramp-FFT and ${\omega}-k$ algorithms and to analyze the effect of antenna positional error for SAR focusing. We expect the system can be further developed into a light-weight SAR system onboard a unmanned aerial vehicle by improving the system with higher sampling frequency, I/Q acquisition, and more stable circuit design.

A COMPARATIVE STUDY ON THE STRENGTH AND THE BONE FORMATION AT THE RATS CALVARIAL DEFECTS OF DFDB GRAFT AND THOSE OF THE COMPOSITE GRAFT WITH DFDB AND RESORBABLE HYDROXYAPATITE (백서 두개골 결손부에 동결 건조 동종 탈회골을 단일매식한 경우와 동결 건조 동종 탈회골과 흡수성 수산화인회석을 복합매식한 경우의 강도 및 골형성에 관한 비교 연구)

  • Seo, Young-Ho;Yim, Chang-Joon;Lee, Jae-Il
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.6
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    • pp.557-564
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    • 2000
  • The bone graft materials can be grossly divided into autogenous bone, allogenic bone, xenogenic bone, and alloplastic material. Much care was given to other bone graft materials away from autogenous bone due to its additional operation for harvesting, delayed resorption and limitation of quantity. Demineralized freeze-dried bone(DFDB) and hydroxyapatite are the representatives of bone graft materials. As resorbable hydroxyapatite is developed in these days, the disadvantage of nonresorbability can be overcome. So we planned to study on the strength and the bone formation at the rats calvarial defects of DFDB graft and those of the composite graft with DFDB and resorbable hydroxyapatite. We used the 16 male rats weighting range from 250 to 300 gram bred under the same environment during same period. After we made the 6mm diameter calvarial defect, we filled the DFDB in 8 rats and DFDB and resorbable hydroxyapatite in another 8 rats. We sacrificed them at the postoperative 1 month and 2 months with the periostium observed. As soon as the specimens were delivered, we measured the compressive forces to break the normal calvarial area and the newly formed bone in calvarial defect area using Instron(Model Autograph $S-2000^{(R)}$, Shimadzu, Japan). The rest of the specimens were stained with H&E(Hematoxylin & Eosin) and evaluated with the light microscope. So we got the following results. 1. In every rats, there was no significant difference between the measured forces of normal bone area and those of the bone graft area. 2. In 1 month, the measured forces at DFDB graft group were higher than those of the DFDB and resorbable hydroxyapatite composite graft group(P<0.05). 3. In 2 months, there was no significant differences between the measured forces of DFDB graft group and those of the DFDB and resorbable hydroxyapatite composite graft group. 4. In lightmicroscopic examination, most of the grafted DFDB were transformed into bone in 1 month and a large numbers of hydroxyapatite crystal were observed in DFDB and resorbable hydroxyapatite composite graft group in 1 month. 5. Both group showed no inflammatory reaction in 1 month. And hydroxyapatite crystals had a tight junction without soft tissue invagination when consolidated with newly formed bone. 6. In both groups, newly formed bone showed the partial bone remodeling and the lamellar bone structures and some of reversal lines were observed in 2 months. From the above results, it is suggested that DFDB and resorbable hydroxyapatite composite graft group had a better resistance to compressive force in early stage than DFDB graft group, but there would be no significant difference between two groups after some period. And it is suggested that the early stage of bone formation procedure of DFDB and resorbable hydroxyapatite composite graft group was slight slower than that of DFDB graft group, but there would be no significant difference between two groups after some period.

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THE EXPERIMENTAL STUDY ON THE CHANGES OF CONDYLAR HEAD FOLLOWING UNILATERAL DISCECTOMY IN RABBIT (가토 편측 악관절원판 제거 후 하악 과두 변화에 관한 실험적 연구)

  • Park, Kwang-Jin;Kim, Kyung-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.18 no.4
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    • pp.758-770
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    • 1996
  • Discectomy is the oldest and most commonly performed operation for the painful temporomandibular joint with internal derangement. It is the one operation for which there are longest follow-up study, with Eriksson, Silver, and Tolvanen et al reporting good results in patients about 30 years after discectomy. About 80% to 90% of patients clinically experience relief from pain and dysfunction after discectomy, and interestingly, the results may improve with time. However such as Myrhaug found headache and Poswillo supposed pain and limitation of movement as postoperative complications, even though this operation had the longest follow-up term, several aspects of discectomy remain unclear. The controversies to discectomy for TMJ with pain and dysfunction have laid emphasis only upon clinical results, and then the histomorphological study was planned to evaluate the morphologic change of TMJ after discectomy. To clarify the nature of the change through an observation on the morphologic changes of articular cartilage and subchondral bone of the condyle resulting from experimental unilateral discectomy in rabbit, the author excised the left articular discs of 12 male rabbits(control 4 rabbits), weighing about 3kg, and at 1, 3, 6, 9 weeks following surgery, harvested both(left surgical site and right nonsurgical sits) TMJ. The specimens were examined with light microscope after H-E and MT stain and the obtained results were as follows. 1. Histopathological features showed thickening of articular zone and active proliferation of fibrocartilaginous zone associated with slight proliferative zone in surgical site than control group. Also replacement of chondrocytes in calcified cartilaginous zone into bone cells was observed. 2. There were thinning of thickness of each zone of articular cartilage except calcified cartilagnous zone was observed in nonsurgical site. 3. In MT stain of condylar trabeculae, there was increased calcification in nonsurgical site than control and surgical site and the degree of calcification was similar in surgical site and control group. 4. In both site of experimental group no features of degenerative changes were observed. From the above results, it is presumed that the morphologic changes of surgical site discectomy are compensatory remodeling process characterized by an hyperplastic reaction of the articular zone and fibrocartilaginous zone filling the void created by removing the disc, and the bone changes are secondary to changes in the cartilage. Increased degree of calcification seen in condylar trabeculae of nonsurgical site results from the excessive use of condyle of that site.

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The Effects of Entrepreneurial Characteristics and Entrepreneurial Intentions : Focusing on Entrepreneurship Education completed Prefounders (창업가 특성이 창업의지에 미치는 영향에 관한 연구 : 창업교육을 이수한 예비창업자를 중심으로)

  • Park, Ji Yu;Yang, Hae Sool
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.2
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    • pp.97-107
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    • 2014
  • Intensive studies have been focused on conditions for business foundation and the entrepreneurship in light of management, economy, and social psychometrics. This study focused on potential effect of entrepreneurial characteristics on environment for entrepreneurial intentions in establishment of orientation of entrepreneurial intentions. Among various factors affecting on starting small and medium size enterprises, how entrepreneur's personal characteristics is related on entrepreneurial intentions was investigated. Manifest questionnaire was distributed among Venture to the professional graduate students, graduate entrepreneurship, and small business start-educated founders in order to deduce the relationship between the entrepreneurial characteristics and the environment of entrepreneurial Intentions. Previous studies and the literature survey were carried out to support for statistics of the questionnaire. 550 answers were collected and analyzed to find that propensity for achievement, innovation, enterprising, risk taking and creativity are key factors influencing inauguration of an enterprise. We have found that among these, risk taking, creativity, and innovation are analyzed to be as a regression coefficient but enterprising a side regression coefficient. Since this study can find its limitation in that comprehensive fields of entrepreneurship were analyzed in general, the result of this study should be used with caution, until more is known about its accessibility for predicting of success or failure of Start-up Company.

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Correlation of sonographic findings with histopathological changes of the bile ducts in rabbits infected with Clonorchis sinensis (간흡충에 감염된 토끼 담관의 초음파 소견과 조직병리학적 병변의 비교)

  • 홍성태;박기흠
    • Parasites, Hosts and Diseases
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    • v.32 no.4
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    • pp.223-230
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    • 1994
  • Clonorchiasis is an important parasitic disease of humans in Korea. The present study intended to compare sonographic findings with histopathological changes in experimental clonorchiasis. Eighteen New Zealand white rabbits were infected with metacercariae of Cknorchis sinensis, and examined 4, 10, and 22 weeks post-infection (PI). Four infected rabbits were treated with praziquantel 10 weeks PI and were examined 12 weeks after treatment. Sonography revealed mild to severe dilatation of the intrahepatic ducts (IHDD) and slightly increased periductal echoes in 12 out of 14 rabbits at 4 weeks PI, and all of the animals after 10 and 22 weeks PI and 12 weeks after treatment. The histopathological lesions were duct dilatation, mucosal hyperplasia, and periductal fibrosis, which progressed from 4 weeks to 22 weeks PI and even in treated rabbits. The dilated intrahepatic ducts over 1 mm diameter were detected by sonography. The present results indicate that sonographic findings are well correlated with histopathological lesions in rabbit clonorchiasis except for early phase of light burden of infection. The sonography has a limitation in discriminating residual sequelae of the ducts after praziquantel treatment.

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