• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.302-308
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• 2009

For the proper tree management of Taxus cuspidata, distributed in the High 1 Ski Slope construction area in Baekwoonsan, Jeungsun-gun, Kangwon-do, the growing states of 323 trees(including transplanted 57trees) are investigated. Tree height, rootcollar diameter, D.B.H., stem condition, apical shoot, dead branch, needle growth condition, 2-year-old needle loss, root condition, tree form are investigated. Taxus cuspidata are mainly growing at the sites, high elevated mountain ridge or slopes facing north. Growing states of Taxus cuspidata, distributed in Baekwoonsan are relatively better than those of Taxus cuspidata and Abies koreana at other subalpine zone in Korea. Damaged trees are mainly due to root-removal through transplanting, root-damages by raising the ground level and digging. Several methods of Taxus cuspidata conservation were suggested.

• Archives of Reconstructive Microsurgery
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• v.3 no.1
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• pp.24-31
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• 1994

The heel, with its specialized fat for shock absorption at heel strike and large surface area for balance and weight bearing, is a important component of normal ambulation. Despite of distinguished improvement in the field of microsurgical free flaps, the choice of reconstruction of the heel has been remained controversial. We reviewed 22 cases of the heel reconstruction using vascularized free flaps from January, 1980 through May, 1993 at the Department of Orthopedic Surgery of Korea University Hospital. The results were as follows: 1. The etiology was traumatic in 21 cases, and chronic ulceration due to burn in 1. 2. The arteries used in free flaps were 11 dorsalis pedis arteries, 2 deep circumflex iliac arteries, 2 supeficial iliac arteries, 2 branches of lateral femoral circumflex iliac arteries, 2 radial arteries, and 3 thorcodorsal arteries. 3. The mean size of the vascularized bone was $4.5cm{\times}3.5cm$, and that of skin flap was $12.1cm{\times}9.2cm$. 4. Of the 22 cases, 19 had a successful outcome and 3 in failure, the causes of failure were thrombosis and infection.

• Applied Microscopy
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• v.34 no.1
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• pp.31-42
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• 2004

Acute respiratory distress syndrome (ARDS) is a kind of acute lung injury characterized by inflammatory disruption of alveolar-capillary barrier and notorious for its high mortality. Neutrophils cause cell damage through the production of free radicals, inflammatory mediators, and proteases in ARDS. $PLA_2$ might serve a primary regulatory role in the activation of neutrophils. This present study was performed to elucidate the effect of rutin known as $PLA_2$ inhibitor on ARDS induced by endotoxin. Endotoxin had increased lung myeloperoxidase (MPO) activity, BAL (bronchoalveolar lavage) protein content, numbers of neutrophils in BALF (bronchoalveolar lavage fluid) compared with those of control rat (p<0.001). In addition, histological evidence of lung injury was correlated with neutrophil influx into alveolar space and cerrous perhydroxide granules were found in lining of endothelial cell, alveolar type I, II cells. In contrast, pretreated group of rutin had significantly decreased all of the parameters (p<0.001). These data suggest that inhibition of $PLA_2$ is one step approach that block the process of ARDS. Accordingly, we conclude that rutin can be used as the prophylactic agent for ARDS on the bases of these experimental results.

• Clinical and Experimental Pediatrics
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• v.45 no.2
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• pp.214-222
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• 2002

Purpose : The aim of this study was to evaluate myocardial injury in children treated with adriamycin by echocardiography, which is non-invasive and safe measurement for children. Methods : Left ventricular dimensions, wall stress, and contractile function were determined by echocardiographic methods in 17 patient recepients with adriamycin chemotherapy at rest(group 1) and during stress(group 2). Twenty age-matched normal subjects were established as control group. Results : End-diastolic dimension was decreased in both groups(group 1; $92{\pm}7%$ of normal, group 2; $87{\pm}8%$ of normal, P<0.05). Left ventricular end diastolic volume and wall mass were also decreased in both groups(group 1; $96{\pm}12mL/m^2$ and $145{\pm}18g/m^2$, group 2; $87{\pm}8mL/m^2$ and $137{\pm}16g/m^2$, respectively, P<0.05 and P<0.05) and group 2 showed lower values than group 1. Meridional end systolic stress(ESSm) was increased in both groups but there was no significant difference between the two groups(group 1; $52.6{\pm}6.2g/cm^2$, group 2; $63.5{\pm}8.5g/cm^2$, P<0.05, normal value $45.7{\pm}3.5g/cm^2$). The load-independent relation of rate-corrected circumferential fiber shortening velocity(Vcfc) to ESSm has a significant abnormal change in 7 out of 17(41%) in group 1 and 12 out of 17(71%) in group 2. Conclusion : The load-dependent systolic index, such as fractional shortening, may fail to show abnormality because of the compensatory changes in preload and afterload which can mask the impaired contractility. Therefore, systolic performance also should be monitored by a load-indepedent contractility index such as slope value of the end-systolic pressure-dimension relation and the position of the left ventricular stress-fiber shortening velocity after exercise.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.4
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• pp.381-388
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• 2017

Purpose: Unpredictable shrinkage of zirconia during sintering process causes discrepancy. Therefore, there have been attempts to reduce discrepancy by milling zirconia after sintering. However, due to the hardness of sintered zirconia, milling takes longer time, causes damage to the machine and causes chip formation. With customized zirconia block using the mean dimension of prepared natural dentition, it is expected to overcome these shortcomings. Materials and methods: The mean dimension of prepared natural dentition was analyzed as STL file after scanning of prepared teeth treated at SNUDH. The transverse, frontal and sagittal planes were set using Mimics and Photoshop. 3D volume was projected on each plane, and the outer line was measured through external tangent line, and the inner line was measured through inflection point of tangent line. Results: The mean height of prepared incisal (N = 57) is $6.60{\pm}1.05mm$, mesiodistal length is $2.98{\pm}0.73mm$, buccolingual length is $2.04{\pm}0.73mm$. The mean height of prepared premolar (N = 15) is $5.37{\pm}1.49mm$, mesiodistal length is $4.10{\pm}1.78mm$, buccolingual length is $5.86{\pm}1.55mm$. And the mean height of prepared molar (N = 13) is $5.11{\pm}1.29mm$, mesiodistal length is $6.80{\pm}1.18mm$, buccolingual length is $7.34{\pm}1.40mm$. Conclusion: Using the mean dimension of prepared natural dentition, it is expected to be able to fabricate customized zirconia block.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.73-77
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• 2017

Recently, fingerprint sensors have widely used for personal information security, and require quality evaluation to reduce an error of their recognition rate. Quality of fingerprint sensors is evaluated by variation of their electrical resistance introducing by contacts between a probe tip and a sensor electrode, Investigation on the materials compatability and structure optimization of probe is required to reduce deformation of sensor electrode for repeatability of quality testing. Nickel, steel(SK4), beryllium copper, and phosphor bronze were considered as probe materials, and beryllium copper was the most appropriate for materials of probe tips, considering indentation and contact resistance while being contacted probe tips on electrodes. Probes of an inspection part were manufactured with the single-unit structure for physical damage prevention and parallel processing capability. Inspection repeatability was evaluated by voltage variation of fingerprint sensors when the specific current was applied. A single-unit inspection part with beryllium copper probe tips showed excellent repeatability within ${\pm}0.003V$ of its voltage variation.

• Journal of the Korean Arthroscopy Society
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• v.13 no.1
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• pp.82-85
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• 2009

Purpose: In anterior cruciate ligament (ACL) reconstruction, preservation of the remnant original tissue might promote graft healing and be helpful in proprioception. But this procedure is difficult and causes the notch impingement. So we introduce a surgical technique that makes a transtibial femoral tunnel at 10 or 2 o'clock position with preservation of remnant tissue. Surgical approach: We tried to preserve the remnant tissue and synovium as much as possible, especially those of tibial attachment and extending to the posterior cruciate ligament (PCL), so as to have some tension and to prevent notch impingement. We set the tibial drill guide at 40~45 degrees and the intra-articular guide tip was 1 mm anterior and medial to the conventional site. The starting point of tibial guide pin was proximal to the pes anserinus and anterior to the medial collateral ligament. When the reamer approached the cortical bone of the tibial articular surface, the reamer must be advanced very carefully to minimize injury to the remnant tissue. The tibial and femoral tunnel at 10 or 2 o'clock position were made with the reamer, the diameter of which was same with that of the graft. Conclusion: We report a remnant preserving technique in ACL reconstruction that makes a transtibial femoral tunnel at 10 or 2 o'clock position

• Korean Journal of Materials Research
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• v.10 no.12
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• pp.812-818
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• 2000

We studied the effects of Ge preamorphization (PAM) on 0.25$\mu\textrm{m}$ Ti-salicide junctions using comparative study with As PAM. For each PAM schemes, ion implantations are performed at a dose of 2E14 ion/$\textrm{cm}^2$ and at 20keV energy using $^{75}$ /As+and GeF4 ion sources. Ge PAM showed better sheet resistance and within- wafer uniformity than those of As PAM at 0.257m line width of n +/p-well junctions. This attributes to enhanced C54-silicidation reaction and strong (040) preferred orientation of the C54-silicide due to minimized As presence at n+ junctions. At p+ junctions, comparable performance was obtained in Rs reduction at fine lines from both As and Ge PAM schemes. Junction leakage current (JLC) revels are below ~1E-14 A/$\mu\textrm{m}^{2}$ at area patterns for all process conditions, whereas no degradation in JLC is shown under Ge PAM condition even at edge- intensive patterns. Smooth $TiSi_2$ interface is observed by cross- section TEM (X- TEM), which supports minimized silicide agglomeration due to Ge PAM and low level of JLC. Both junction break- down voltage (JBV) and contact resistances are satisfactory at all process conditions.

• The Journal of the Petrological Society of Korea
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• v.28 no.2
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• pp.129-141
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• 2019

The Eoraesan area, Chungju, which is located in the northwestern part of Ogcheon Metamorphic Zone, Korea, mainly consists of the Neoproterozoic Gyemyeongsan Formation and the Mesozoic igneous rocks which intruded it. The metaacidic rocks (MAR) of the Gyemyeongsan Formation show a maximum radioactive value, and the Early Jurassic biotite granite is regionally distributed in this area. In this paper is researched the microstructure related to the growth of rare-earth mineral of allanite in the MAR, and is considered the source and occurrence time of rare-earth element (REE) mineralization. The MAR is mainly composed of alkalic feldspar (mainly microcline), quartz, iron-oxidizing mineral, biotite, muscovite, plagioclase, hornblende, allanite, zircon, epidote, fluorite, apatite, garnet, (clino)zoisite etc. The radioactive elements contained in the allanite cause a dark brown hale in the surrounding biotite, and the allinte also occurs as aggregate along the regional foliation. The deflection of regional foliation and the strain shadows, which are common to the pre-tectonic porphyroblast grown before the formation of regional foliation, can't be observed around most allanites (aggregates). The grain size and orientation of ironoxidizing mineral included in the allanite aggregate are the same as those in the matrix. It is recognized the hydrothermal conversion of hornblende to biotite due to the intrusion of igneous rock, and the secondary biotite occurs and contacts with allanite, zircon, epidote etc. These microstructures indicate that the rare-earth mineral of allanite (aggregate) grew by the hydrothermal alteration due to the intrusion of igneous rock after the formation of regional foliation. It is considered that the REE mineralization is closely related to the intrusion of Early Jurassic biotite granite which is regionally distributed in this area.

• Journal of the Korean Arthroscopy Society
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• v.7 no.2
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• pp.201-205
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• 2003

Purpose : Authors experienced cases of chronic ACL tear with spur-like lesion on the tibial condyle which is different from the lateral capsular sign and degenerative change and evaluated the significance of 'spur-like lesion' in relations with chronic ACL injury. Material and Method : We have 5 patients with spur-like lesion on the lateral tibial condyle in simple radiogram. The location, shape and size of the lesion were studied using radiogram and MRI. Cause of injury, associated injury and chronicity of the ACL tear were analyzed. All 5 patients were male, and mean age was 33.8 $(17\~46)$ years. Result : The spur-like lesion was located from 3.8 mm(avg.) below the articular surface of the lateral tibial condyle to the apex of the fibular head and protruded laterally or inferolaterally from just posterior to the Gerdy's tubercle with a round or sharp-end triangular shape. Average length was 6 mm and average width ortho base was 9.2 mm. The cause of injury were sports jnjury 4 cases and traffic accident in one. The chronicity of the ACL tear was average 10.7(8 months$\~$23 years) years and medial meniscus tear was shown in all cases and lateral meniscus tear in three. Conclusion : We suggest that a patient who has a history of trauma with spur-like lesion on the lateral tibial condyle of the knee is expected to have chronic ACL tear.