• The Journal of Korean Academy of Prosthodontics
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• v.39 no.6
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• pp.709-734
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• 2001

The aims of this experiment were to investigate the strain and temperature changes simultaneously within autopolymerzing acrylic resin specimens. A computerized data acquisition system with an electrical resistance strain gauge and a thermocouple was used over time periods up to 180 minutes. The overall strain kinetics, the effects of stress relaxation and additional heat supply during the polymerization were evaluated. Stone mold replicas with an inner butt-joint rectangular cavity ($40.0{\times}25.0mm$, 5.0mm in depth) were duplicated from a brass master mold. A strain gauge (AE-11-S50N-120-EC, CAS Inc., Korea) and a thermocouple were installed within the cavity, which had been connected to a personal computer and a precision signal conditioning amplifier (DA1600 Dynamic Strain Amplifier, CAS Inc., Korea) so that real-time recordings of both polymerization-induced strain and temperature changes were performed. After each of fresh resin mixture was poured into the mold replica, data recording was done up to 180 minutes with three-second interval. Each of two poly(methyl methacrylate) products (Duralay, Vertex) and a vinyl ethyl methacrylate product (Snap) was examined repeatedly ten times. Additionally, removal procedures were done after 15, 30 and 60 minutes from the start of mixing to evaluate the effect of stress relaxation after deflasking. Six specimens for each of nine conditions were examined. After removal from the mold, the specimen continued bench-curing up to 180 minutes. Using a waterbath (Hanau Junior Curing Unit, Model No.76-0, Teledyne Hanau, New York, U.S.A.) with its temperature control maintained at $50^{\circ}C$, heat-soaking procedures with two different durations (15 and 45 minutes) were done to evaluate the effect of additional heat supply on the strain and temperature changes within the specimen during the polymerization. Five specimens for each of six conditions were examined. Within the parameters of this study the following results were drawn: 1. The mean shrinkage strains reached $-3095{\mu}{\epsilon},\;-1796{\mu}{\epsilon}$ and $-2959{\mu}{\epsilon}$ for Duralay, Snap and Vertex, respectively. The mean maximum temperature rise reached $56.7^{\circ}C,\;41.3^{\circ}C$ and $56.1^{\circ}C$ for Duralay, Snap, and Vertex, respectively. A vinyl ethyl methacrylate product (Snap) showed significantly less polymerization shrinkage strain (p<0.01) and significantly lower maximum temperature rise (p<0.01) than the other two poly(methyl methacrylate) products (Duralay, Vertex). 2. Mean maximum shrinkage rate for each resin was calculated to $-31.8{\mu}{\epsilon}/sec,\;-15.9{\mu}{\epsilon}/sec$ and $-31.8{\mu}{\epsilon}/sec$ for Duralay, Snap and Vertex, respectively. Snap showed significantly lower maximum shrinkage rate than Duralay and Vertex (p<0.01). 3. From the second experiment, some expansion was observed immediately after removal of specimen from the mold, and the amount of expansion increased as the removal time was delayed. For each removal time, Snap showed significantly less strain changes than the other two poly(methyl methacrylate) products (p<0.05). 4. During the external heat supply for the resins, higher maximum temperature rises were found. Meanwhile, the maximum shrinkage rates were not different from those of room temperature polymerizations. 5. From the third experiment, the external heat supply for the resins during polymerization could temporarily decrease or even reverse shrinkage strains of each material. But, shrinkage re-occurred in the linear nature after completion of heat supply. 6. Linear thermal expansion coefficients obtained from the end of heat supply continuing for an additional 5 minutes, showed that Snap exhibited significantly lower values than the other two poly(methyl methacrylate) products (p<0.01). Moreover, little difference was found between the mean linear thermal expansion coefficients obtained from two different heating durations (p>0.05).

• The Journal of the Korean bone and joint tumor society
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• v.9 no.2
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• pp.178-189
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• 2003

Purpose: The current study was designed to investigate the expression pattern of chemokine in musculoskeletal tumors, and between primary osteosarcoma and recurred, and postchemotherapy one. Materials and methods: Ten primary soft tissue and bone tumors, one primary, one recurred, one post-chemotherapy osteosarcoma, and one normal control patients were included in the current study. RT-PCR and RPA were used for the investigation of the expression of cytokines and chemokines. Fisher's exact test in SPSS was used for the statistical analysis. Results: IL-8 and TNF-${\alpha}$ were expressed in all tumor tissues, IFN-${\gamma}$ was in all except two cases, RANTES was in 5 soft tissue tumors and 4 bone tumors, GRO-${\alpha}$was in one soft tissue tumor and 2 bone tumors, and MCP-1 and IP-10 were in two bone tumors and in all the other group. In recurred osteosarcoma all the cytokines and chemokines were expressed, and the degree of the expression was stronger than the primary, except IFN-${\gamma}$. After chemotherapy, RANTES, IFN-${\beta}$ and TGF${\beta}_1$ among the TGF${\beta}$isoforms were expressed. Conclusion: There were differences in the expression of cytokines and chemokines in some different bone and soft tissue tumors, even though it was impossible to support this statistically due to small numbers of cases. The expression pattern of IFN-${\gamma}$and TGF-${\beta}$ isoform in osteosarcoma could be used for the study of tumor recurrence and the changes after chemotherapy.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.70-75
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• 1986

The population and kinds of algae causing the waterbloom on the rice seedling bed and the damage of young rice plant by the nuisance green phytoplanktonic algae in rice field were studied to find out the efficiency of fertilizers and the effect of methods of fertilizers application in the rice field, laboratory, pot and green house. pot and green house. The results obtained were summarized as follows; 1. In the rice seedling bed, the kinds of algae causing waterblooms were identified mainly photosynthetic bluegreen algae as the Anabaena, Ulothrix and Oscillatoria spp. in reclaimed saline soil. Micromonospora, Oscillatoria, and Chlamydomonas spp. were habitated mainly in plain. Whereas, Spyrogyra, Oscillatoria and Navicula spp. were identified mainly in mauntainous area. 2. In the rice field, the nuisance phytoplanktonic green algae were identified mainly Scenedesmus, Chlamidospora, and Micromonospora spp. in Gimjae plain, in Namweon mountainous area and Gangjin costal plain, respectively. 3. The algal biomass has been havily habitated in which rice field were constituted with high pH value and high concentration of $NH^+_4-N$ and $NO^-_3-N$ in surface water and in soil with the optimum temperature for the algal growth ($22-30^{\circ}C$). 4. In the laboratory experiment, maximum algal biomass were obtained at levels of 80 ppm for the nitrogen and 20 ppm for the phosphorus. And were obtained of the levels of 40 ppm in the case of joint application of N and $P_2O_5$. 5. From the pot experiment, compare of the control plot, an addition of nitrogen alone or nitrogen+phosphorus enhanced algal biomass while the phosphorus alone did not. 6. Surface application of fertilizer was remarkably increased of algal biomass than did the whole layer or deep layer application.

• Journal of Korean Orthopaedic Sports Medicine
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• v.10 no.1
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• pp.35-40
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• 2011

Purpose: This study was performed to evaluate the diagnostic usefulness of ankle stress radiograph for evaluation of chronic lateral ankle instability. Materials and Methods: Among patients undergoing the modified-Brostrom procedure, 42 cases with complete rupture of the anterior talofibular ligament were enrolled in this study. Sixty Korean adults (120 cases) were recruited as the control group. Radiologic measurement of talar tilt and anterior talar translation was performed through stress radiographs using Telos device. We obtained the normal range of Korean adults, and used as a standard value for judgment of mechanical instability. We analyzed the sensitivity, specificity, positive and negative prediction value of ankle stress radiograph. Results: On ankle stress radiograph, normal range of talar tilt angle and anterior talar translation was below $8.3^{\circ}$, below 7.6mm. Talar tilt angle on varus stress radiograph showed 57% of sensitivity, 97% of specificity, 89% of positive and 86% of negative prediction value. Anterior talar translation on anterior drawer stress radiograph showed 69% of sensitivity, 97% of specificity, 91% of positive and 90% of negative prediction value. Conclusion: Ankle stress radiograph had a good specificity, positive and negative prediction value for the evaluation of mechanical instability. However it underestimated the mechanical instability of ankle joint. It must be remembered that normal stress radiograph does not exclude ankle instability.

• KSBB Journal
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• v.25 no.6
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• pp.572-576
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• 2010

Biological products, such as live varicella vaccine, are composed of biological substances derived from biological organisms. It is very difficult to identify these biologics' characteristics by analysis of simple physical and chemical methods alone. So the reference material is essential in order to evaluate the quality of bilogics. The 1'st national standard for varicella live vaccine was manufactured, established in 2002 and 2003, and have been used for the manufacturer's quality control and national lot release since then. As the lack of its availability and the decrease of its stability, this study was initiated by National Institute of Food and Drug Safety Evaluation (NiFDS) in 2008 to manufacture and establish the 2nd national standard for varicella live vaccine. The candidate material was manufactured from one of domestic manufacterers and the joint research of the NiFDS and manufacturers of varicella live vaccine was conducted to estimate of the reliable virus content. In the collaborative study, 3 laboratories including NiFDS performed the virus content test more than 7 times and all assay results were statistically analyzed. The mean coefficient of variation (CV) was 1.24%, and the geometric mean titre (GMT) variation range of each laboratory was low. On the basis of the results of this study, the candidate material of 2nd national standard for varicella live vaccine was assigned a potency of 4.26 log10 pfu/0.5 mL, when reconstituted in 0.7 mL.

• Journal of Korean Society of Steel Construction
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• v.23 no.4
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• pp.503-514
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• 2011

In this research, the seismic connection details for two concrete-filled U-shape steel beam-to-H columns were proposed and cyclically tested under a full-scale cruciform configuration. The key connecting components included the U-shape steel section (450 and 550 mm deep for specimens A and B, respectively), a concrete floor slab with a ribbed deck (165 mm deep for both specimens), welded couplers and rebars for negative moment transfer, and shear studs for full composite action and strengthening plates. Considering the unique constructional nature of the proposed connection, the critical limit states, such as the weld fracture, anchorage failure of the welded coupler, local buckling, concrete crushing, and rebar buckling, were carefully addressed in the specimen design. The test results showed that the connection details and design methods proposed in this study can well control the critical limit states mentioned above. Especially, the proposed connection according to the strengthening strategy successfully pushed the plastic hinge to the tip of the strengthened zone, as intended in the design, and was very effective in protecting the more vulnerable beam-to-column welded joint. The maximum story drift capacities of 6.0 and 6.8% radians were achieved in specimens A and B, respectively, thus far exceeding the minimumlimit of 4% radians required of special moment frames. Low-cycle fatigue fracture across the beam bottom flange at a 6% drift level was the final failure mode of specimen A. Specimen B failed through the fracture of the top splice plate of the bolted splice at a very high drift ratio of 8.0% radian.

• Radiation Oncology Journal
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• v.23 no.2
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• pp.71-77
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• 2005

Purpose: This retrospective study was conduced to analyze the treatment results and to evaluate the prognostic factors affecting the survival of nasopharyngeal carcinoma patients. Materials and Methods: From 1987 to 2002, we analyzed 43 patients who had nasopharyngeal carcinomas that were histologically confirmed and who had also completed the planned radiation therapy course at Keimyung University Dongsan Medical Center According to the 6th edition of American Joint Committee on Cancer staging system, 12 patients ($27.9\%$) were at Stage 11, 13 ($30.2\%$) were at Stage III and 18 ($41.9\%$) were at Stage IV Histopathologically, there were 15 ($34.9\%$) squamous cell carcinomas, 8 ($18.5\%$) nonkeratinizing carcinomas, 17 ($39.5\%$) undifferentiated carcinomas, and 3 ($7.0\%$) lymphoepitheliomas. Among the total 43 patients, 31 patients ($72.1\%$) were treated with only radiation therapy. Neoadjuvant chemotherapy was peformed on 7 patients ($16.3\%$) and concurrent chemoradiotherapy was performed on S patients ($11.6\%$). Cisplatin and 5-Fluorouracil were administered to 11 patients for 4 cycles, and Cisplatin and Taxotere were administered to 1 patient for 6 cycles. The range of the total radiation dose delivered to the primary tumor was from 61.2 to 84 Gy (median 70.4 Gy), The follow-up period ranged from 2 to 197 months with median follow-up of 84 months. Results: The local control rate at 6 months after radiation therapy was $90.7\%$. The five year overall survival and disease free survival rates were $50.7\%$ and $48.9\%$, respectively. On the multivariate analysis, the age, T-stage ($T_{1-3}\;vs\;T_4$), N-stage and AJCC stage were the statistically significant prognostic factors affecting survival (p<0.05). The patterns of failure were as follows: local failure only in 3 patients ($7.0\%$), local and systemic failure in 1 patient ($2.3\%$), and distant metastasis only in 11 patients ($25.6\%$). Conclusion: The prognostic factors affecting the outcome of nasopharyngeal carcinoma were age, T-stage (7$T_{1-3}\;vs\;T_4$), N-stage and stage. Because systemic metastasis was the main failure pattern noted for nasopharyngeal carcinoma, systemic chemotherapy is needed to decrease the rate of distant metastasis for nasopharyngeal carcinoma. In audition, research for more effective chemotherapeutical regimens and schedules is also needed.

• Korean Journal of Hospice Care
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• v.8 no.1
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• pp.1-12
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• 2008

Perpose: The purpose of this study was to investigate the perception of death between Korean and Chinese nursing students. And it will help develop curriculum for preparing death, the quality of hospice care, as well as nursing education and practice. Methods: Data was collected from 492 nursing students participated(248 Korean and 244 Chinese) by questionnaire designed for examining Death Orientation (Thorson & Powell, 1988). They were analyzed using Cronbach's Alpha coefficients, factor analysis, t-test, ANOVA and regression analysis (SPSS; win 12.0 version) Results: More than half of the Korean nursing students followed a religion (58.5%) while the majority of Chinese nursing students did not follow a religion (93.9%). In the view of the afterlife, nursing students in China had two views. 'I really don't know what happens after a person dies (30.3%)' and ‘There is no afterlife and death is the end (29.5%)’. On the other hand the Korean nursing students’ answer were, 'After dying, a person goes to heaven or hell (27.3%)' and 'I really don't know what happens after a person dies. (22.9%)' The study also found that the average of 25 items in Death Orientation is 2.36points of nursing students in Korea and 2.50points of nursing students in China. This means that the concern, anxiety and fear were of the middle level for the Chinese Students and were higher than Korean students (t=3.51, p=.000). In the low factor of death orientation, those in Korea had higher 'anxiety of burden to family' than those in China (t=-3.50, p=.001). The nursing students in China had higher 'anxiety of the unknown (t=4.96, p=.000)', 'fear of suffering (t=6.88, p=.000), 'fear of extinction body and life (t=5.20, p=.000), 'fear of lost self-control(t=2.12, p=.034)', and 'anxiety of future existence and nonexistence (t=2.33, p=.020)' than those in Korea. There was no statistically significant difference for the 'concern of body and fear of identity lost' category. The death orientation of Korean nursing students had statistically significant differences according to age (t=3.20, p=.002), religion (t=2.56, p=.011), and afterlife (F=4.64, p=.000). The contribution of Death Orientation had a statistically significant difference, the afterlife variable (0.735, p=0.001). The death orientation of Chinese nursing students did not have any statistically significant differences. Conclusion: In conclusion, there were differences in death orientation between Korean and Chinese nursing students. In particular, those who believed in afterlife showed acceptance of death. The results of this study suggest that nursing curricula should include education program on death and spiritual nursing. Additional studies are needed to establish death education in China with careful considerations on Chinese policies, cultures and social systems.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.18 no.3
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• pp.99-106
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• 2018

Mucolipidosis type III (pseudo-Hurler polydystrophy) is a mucolipids degrading disorder caused by a mutation in the GNPTAB gene and is inherited by autosomal recessive. It is diagnosed by examining highly concentrated mucolipids in blood and the diagnosis can be confirmed by genetic testing. Mucolipidosis type III is a rare and progressive metabolic disorder. Its initial signs and symptoms usually occur around 3 years of age. Clinical manifestations of the disease include slow growth, joint stiffness, arthralgia, skeletal abnormalities, heart valve abnormalities, recurrent respiratory infection, distinctive facial features, and mild intellectual disability. Here, we are presenting two siblings of mucolipidosis type III, a 4-year-old female and a 2 years and 7 months old male with features of delayed growth and coarse face. The diagnosis was confirmed by [c.2715+1G>A(p.Glu906Leufs*4), c.2544del(p.Glu849Lysfs*22)] mutation in targeted gene panel sequencing. In this case, c.2544del is a heterozygote newly identified mutation in mucolipidosis type III and was not found in the control group including the genome aggregation database. And it is interpreted as a pathogenic variant considering the association with phenotype. Here, we report a Korean mucolipidosis type III patients with novel mutations in GNPTAB gene who have been treated since early childhood. Owing to recent development of molecular genetic techniques, it was possible to make early diagnosis and treatment with pamidronate was initiated appropriately in case 1. In addition to these supportive therapies, efforts must be made to develop fundamental treatment for patients with early diagnosis of mucolipidosis.

• Korean Journal of Heritage: History & Science
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• v.52 no.3
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• pp.74-93
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• 2019

The Bird Track Site in the Haman Formation in Yongsanri (Natural Monument No. 222) was reported on the named Koreanaornis hamanensis and Jindongornipes kimi sauropod footprint Brontopodus and ichnospecies Ochlichnus formed by Nematoda. This site has outstanding academic value because it is where the second-highest number of bird tracks have been reported in the world. However, only 25% of the site remains after being designated a natural monument in 1969. This is due to artificial damage caused by worldwide fame and quarrying for flat stone used in Korean floor heating systems. The Haman Formation, including this fossil site, has lithofacies showing reddish-grey siltstone and black shale, alternately. The boundary of the two rocks is progressive, and sedimentary structures like ripple marks and sun cracks can clearly be found. This site was divided into seven formations according to sedimentary sequences and structures. The results of a nondestructive deterioration evaluation showed that chemical and biological damage rates were very low for all formations. Also, physical damage displayed low rates with 0.49% on exfoliation, 0.04% on blistering, 0.28% on break-out; however, the joint crack index was high, 6.20. Additionally, efflorescence was observed on outcrops at the backside and the northwestern side. Physical properties measured by an indirect ultrasonic analysis were found to be moderately weathered (MW). Above all, the southeastern side was much fresher, though some areas around the column of protection facility appeared more weathered. Furthermore, five kinds of discontinuity surface can be found at this site, with the bedding plane showing the higher share. There is the possibility of toppling failure occurring at this site but stable on plane and wedge failure by means of stereographic projection. We concluded that the overall level of deterioration and stability were relatively fine. However, continuous monitoring and conservation treatment and management should be performed as situations such as the physicochemical weathering of the fossil layer, and the efflorescence of the mortar adjoining the protection facility's column appear to be challenging to control.