• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.21-29
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• 2023

In this study, the stress characteristics of temporary fixed steel rods were analyzed in the "temporary fixing system using internal prestressing tension", which is mainly applied to the construction of superstructures by FCM. It was difficult to confirm the changes in initial tensile force in this system because the steel rod was internally connected to the pier and the PSC BOX. Therefore, measurement was performed before and after the completion of each segment using an FBG sensor to measure the change in the micro length of the steel rod. The results of the analysis showed that 75% to 90% of the maximum vertical contraction of the steel rod that occurred until the completion of the cantilever segment occurred in the fixing ~ 1segment, and the maximum loss of initial prestressing force was 39%. Such excessive loss of tension force to 1 segment means that tension is needed to improve the precision of construction during the fixation, and re-tension is needed to secure stability for conduction of cantilever segments after the completion of 1segment. In the 2 ~ last segment, the stress of the steel rod decreased gradually, and in the summer, the decrease in stress tended to partially recover due to the increase in the length of the steel rod corresponding to the increase in the vertical volume of PSC BOX. The dominant factor in the stress change in 2~ last segment in this phenomenon is judged to be the change in the length of the steel rod according to the temperature. Unlike the change in length, the relaxation was 1.2-2.7%, which was mostly offset by the opposite stress corresponding to the temperature stress. Therefore, a plan was proposed to improve the internal stress, such as adjusting the fixation time.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.1
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• pp.1-8
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• 2022

Purpose: The purpose of this study was to evaluate the effects of mouthwash containing sodium chloride on dental plaque, gingival inflammation index, and bad breath through clinical trials. Materials and Methods: This trial was designed as 12 weeks and subjects were instructed to put an appropriate amount of the provided standard detergent on a toothbrush and brush their teeth 3 times a day. They were instructed to gargle a mouthwash provided to each group after brushiung. Efficacy was evaluated by performing gingival and periodontal-related index tests, dental plaque changes, and bad breath tests a total of 5 times. All data were statistically analyzed using 2-sample t-test, paired t-test to compare between groups at 95% significance level using IBM SPSS Statistics 24.0. Results: As a result of the PMA index measurement, the gingivitis improvement effect rate of the experimental group compared to the control group was 107.63% after 8 weeks and 73.08% after 12 weeks. As a result of the PHP index measurement, the plaque improvement effect rate of the experimental group compared to the control group was 79.37% after 8 weeks and 74.06% after 12 weeks. As a result of measuring volatile sulfur compounds using Oral Chroma, the effectiveness of improvement in bad breath in the experimental group was 65.06% after 8 weeks and 99.33% after 12 weeks, compared to the control group. Conclusion: As a result of this study, it was confirmed that effective gingivitis alleviation, plaque removal effect and bad breath removal effect can be expected when a mouthwash containing sodium chloride, green tea extract, and sodium monofluorophosphate is used.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.1
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• pp.13-21
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• 2022

Mushroom waste medium refers to the waste biomass generated after mushroom cultivating. And, the burden of treatment on mushroom farmhouse is increasing due to the absence of appropriate treatment method and increase of treatment costs of the mushroom waste medium. In this study, in order to assess the energy value of mushroom waste medium by an anaerobic digestion, methane potential and anaerobic organic matter decomposition characteristics were investigated. The theoretical methane potential(B_th) of mushroom medium(MM) was 0.481 Nm³-CH₄/kg-VS_added, and the B_th of mushroom waste medium(MWM) was 0.451 Nm³-CH₄/kg-VS_added. The biochemical methane potential(B_u-exp) of MWM was increased by 18% from 0.155 for MM to 0.183 Nm³-CH₄/kg-VS_added for MWM. In the reaction kinetics analysis by the Modified Gompertz model, the maximum methane production rate(R_m) was increased from 4.59 for MM to 7.21 mL/day for MWM and the lag growth phase time(λ) was decreased from 2.78 for MM to 1.96 days for MWM. In the reaction kinetics analysis by the parallel first order kinetics model, the easily degradable organic matter(VS_e) content was increased by 5.89% and the persistently degradable organic matter(VS_p) content was 2.03% in MWM, and the non-degradable organic matter(VS_NB) content was decreased by 7.85%. Therefore, it was evaluated that the anaerobic digestion efficiency of MWM was increased. The anaerobic digestion efficiency of MWM was assessed to be more improved than that of MM.

• Journal of the Korean Orthopaedic Association
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• v.54 no.6
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• pp.528-536
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• 2019

Purpose: This study examined the effects of a weekly teriparatide on the change in vertebral compression ratio, back pain, and vertebral fracture healing in osteoporosis patients with vertebral compression fractured induced by low energy trauma. Materials and Methods: From January 2016 to December 2017, 57 patients with severe osteoporotic vertebral fractures with a T score of -3.5 or less were included in this study. The changes in the vertebral compression ratio, visual analogue scale (VAS), Oswestry disability index (ODI) for at least 6 months were examined. The morphology of bone marrow edema and the presence of intervertebral cleft, osteocalcin, and N-terminal telopeptide (NTx) were also investigated. Results: The mean compression ratio was 20% in the experimental group (teripratide group) at 3 months, and 38% in the control group. A significant difference in the compression ratio of the vertebral body over time was observed (p<0.05; t-test). A comparison of the compression ratio of the vertebral body with the follow-up duration in each group showed no significant increase in the, compression (p=0.063) in the experimental group and a significant increase in the control group (p<0.05). The mean time to reach the plateau of the compression rate was one month in the experimental group and three months in the control group. The VAS score in the experimental and control group was 0.39 and 1.07 points, respectively. The ODI score in the experimental and control group was 33.72 and 39.52, respectively. At the last follow-up radiographs, there were no cases with an intervertebral cleft (0%) in the experimental group and 1 case (2.2%) in the control group. A significant difference in the osteocalcin level was observed between the injury and 6 months after the injury (p=0.003). In addition, there was no significant difference in the NTx level between the injury and 6 months after injury (p=0.960). Conclusion: In vertebral compression fractures patients with severe osteoporosis, a weekly teriparatide can promote the union of fractures, prevent further collapse of the vertebral body, and reduce the back pain faster.

• East European & Balkan Studies
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• v.35
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• pp.153-186
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• 2013

Literature has been special for the Polish who suffered from the numerous invasions from surrounding countries for her geographical location at the center of Europe. In the late 18th century at a time when Poland was divided and ruled by Russia, Prussia and Austria, literature played an important role in uniting Poland. During the 2nd world war in which Poland was occupied by the Soviet Union and by Germany, and during the Cold War period under socialism system(1948~1989), the Polish literature was in the front to keep unique national culture with overseas migration community at the center. The Polish Diaspora literature from 19th century up to now has naturally embodied national sufferings from foreign powers in their literary tradition linked to the problem of 'migration'. In addition, they belong to other cultural sphere, but keep their own unique identity, which is similar to Korean Diaspora literature to a great degree. This study has two stages. In the first stage, it figures out the formation and trend of the Polish Diaspora literature followed by their meaning in the history of Polish literature. In the second stage, specific texts (two dramas) are analyzed before and after system transition in 1989. * Before system transition: S. Mrożek, Emigranci (1974), * After system transition: J. Głowacki, Antygona w Nowym Yorku (1992) Mrożek and Głowacki had themselves migration experiences with high achievement and recognition in literature not only in Poland but also in the world. In their works, hardships as 'strangers' in foreign countries, emotional wandering and agony, nostalgia to lost home land and exploration of identity were described vividly. By comparing the 2 literature texts, this study attempts to trace the change of Diaspora consciousness which Polish migrants experienced in foreign countries with different political system like socialism and capitalism.

• Journal of the Korean Orthopaedic Association
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• v.54 no.2
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• pp.164-171
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• 2019

Purpose: A dedifferentiated chondrosarcoma is a rare lethal tumor characterized by a low grade chondrosarcoma juxtaposed with a high grade dedifferentiated sarcoma, such as osteosarcoma, fibrosarcoma. The aim of our study was to document the clinical manifestation and oncologic outcomes of a dedifferentiated chondrosarcoma. Materials and Methods: This study identified 11 patients who were diagnosed and treated for dedifferentiated chondrosarcoma between January 2007 and December 2016. The identified cohort was then reviewed regarding age, sex, symptom onset, tumor location, magnetic resonance imagings (MRIs), surgical margin, and pathologic diagnosis. The time to local recurrence and/or metastasis, follow-up duration, and the patients' final status were analyzed. Results: The patients were comprised of 7 males and 4 females with a mean age of 54 years (range, 33-80 years). The location of the tumor was in the femur in 6 cases, pelvis in 4 cases, and metatarsal in 1 case. The average tumor diameter was 12.7 cm (range, 6.0-26.1 cm). At the time of diagnosis, 2 patients showed pathologic fracture; 1 patient was Enecking stage IIA, 9 patients were stage IIB, and 1 patient was stage III. Eight patients were classified as a primary dedifferentiated chondrosarcoma and 3 patients were secondary. One of the primary lesions was misinterpreted initially as a low grade chondroid lesion by MRI and underwent curettage. Local recurrence occurred in 8 cases and distant metastasis occurred in 10 cases with a mean duration of 8 months (range, 2-23 months) and 7 months (range, 1-32 months), respectively. The three-year overall survival of patients with dedifferentiated chondrosarcoma was 18%, and 10 patients died due to disease progression. Conclusion: Dedifferentiated chondrosarcoma developed lung metastases in the early period of the clinical courses and the prognosis was dismal.

• Journal of the Korean Orthopaedic Association
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• v.54 no.4
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• pp.317-326
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• 2019

Purpose: To compare and analyze the rate of prevention of two venous thromboembolism prophylaxis guidelines in patients with artificial joint arthroplasty and hip joint fracture. Proper prophylaxis for preventing thromboembolism in orthopedic surgery is significant because of this fetal complication. Materials and Methods: This study compared and retrospective analyzed the rate of prevention using the medical records and radiographs of patients who underwent orthopedic surgery from March 2009 to February 2011 according to the American College of Chest Physicians (ACCP) guidelines and from March 2012 to February 2014 according to the American Academy of Orthopedic Surgeons (AAOS) guidelines. Results: The guidelines for venous thromboembolism prophylaxis have been applied to patients with artificial joint replacement and hip joint fracture, the compliance rate of the ACCP guidelines was 56.0% before surgery, 67.0% after surgery with chemical prophylaxis, and 80.5% with mechanical prophylaxis. In addition, the compliance rate of the AAOS guidelines was 74.1% with chemical prophylaxis, and 88.3% with mechanical prophylaxis, which was higher than the ACCP guidelines. The compliance rates of mechanical and chemical prophylaxis before and after surgery of the ACCP guidelines, and the compliance rate of mechanical and chemical prophylaxis of the AAOS guidelines were compared and analyzed. The results revealed statistical significance (p<0.05) before and after total knee replacement arthroplasty and hip joint fracture internal fixation and total high risk orthopedic surgery. Conclusion: Raising the compliance rate of prophylaxis of venous thromboembolism in high risk orthopedic surgery is necessary and people should follow the guidelines for a unified direction depending on which situation they are in.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.52-58
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• 2019

Purpose: Fungal periprosthetic joint infection (PJI) is a rare but devastating complication following total knee arthroplasty (TKA). On the other hand, a standardized procedure regarding an accurate treatment of this serious complication of knee arthroplasty is lacking. The clinical progress of staged reimplantation in patients who had fungus-related PJI after TKA was reviewed retrospectively. Materials and Methods: Ten patients who had a fungal related PJI after TKA between 2006 and 2017 using staged reimplantation surgery were reviewed. These patients were compared with 119 patients who had a PJI in the same period. The failure rate of infection control, intravenous antimicrobial using the period, and the clinical results were evaluated by comparing the range of motion and Korean knee score (KKS) between pre-staged reimplantation and the last follow-up. Results: In the fungal infection group, 7 out of 10 cases (70.0%) had failed in infection control using staged reimplantation and in the non-fungal group, 7 out of 119 cases (5.9%) had failed (p=0.04). In the non-fungal group, the mean duration of antibiotics was 6.2 weeks. In the fungus group, the mean duration of antibiotics was 15.3 weeks, which was 9.1 weeks longer (p<0.001). The range of motion of the knee was increased in the two groups (p=0.265). At the last follow-up, the KKS was 71.01 points in the non-fungal group and 61.3 points in the fungal group (p=0.012). Erythrocyte sedimentation rate and C-reactive protein (CRP) decreased in the two groups, but the CRP was significantly different in the two groups (p=0.007). Conclusion: The treatment of fungus-related PJIs using staged reimplantation showed uneven clinical progress and unsatisfactory clinical improvements compared to non-fungal PJI. Therefore, it is necessary to consider the use of an antifungal mixed cement spacer at resection arthroplasty and oral antifungal agent after reimplantation.

• Journal of the Korean Orthopaedic Association
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• v.54 no.3
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• pp.261-268
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• 2019

Purpose: The authors measured the anteversion of the femoral neck and acetabulum and the sum of the two values in normal Korean people by computed tomography. The authors examined the normal range of the values to analyze the difference in sex and sides as well as the relationship between the femoral neck and acetabular anteversion. Materials and Methods: The authors measured the anteversion of the femoral neck and acetabulum in 118 normal Korean adult males and 114 females aged between 21 and 49 on both the right and left sides by computed tomography and calculated the sum of anteversion. The authors analyzed the mean and standard deviation, and investigated the sex differences and side differences, as well as the relationship between the acetabular anteversion and femoral neck anteversion statistically. Results: The anteversion of the acetabulum in males was 15.3°±6.1° on the right side and 15.3°±6.6° on the left side. The anteversion of the femoral neck in males was 5.3°±7.6° on the right side and 1.5°±9.2° on the left side according to the Hernandez et al. method. The anteversion of acetabulum in females was 16.8°±5.4° on the right side and 16.3°±5.8° on the left side. The anteversion of femoral neck in females was 10.3°±8.2° on the right side and 7.9°±8.2° on the left side according to Hernandez et al. method. No difference in acetabular anteversion, and a significant difference in the femoral neck anteversion on both the right and left sides were observed between males and females. No difference of acetabular anteversion was observed between the right and left sides, but a significant difference in femoral neck anteversion was noted between the right and left sides measured by either the Hernandez et al. method or Weiner et al. method. The Pearson coefficient revealed no correlation between the femoral neck anteversion and acetabular anteversion. Conclusion: No difference in the acetabular anteversion was observed, but there was a significant difference in femoral neck anteversion between males and females. A significant difference in femoral neck anteversion was observed between the right and left sides. No correlation was noted between the anteversion of the femoral neck and acetabulum.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.1-8
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• 2019

Globally, the elderly population is increasing rapidly, which means that the number of deformity correction operations for elderly spine deformity patient has increased. On the other hand, for aged patients with deformity correction operation, preoperative considerations to reduce the complications and predict a good clinical outcome are not completely understood. First, medical comorbidity needs to be evaluated preoperatively with the Cumulative Illness Rating Scale for Geriatrics or the Charlson Comorbidity Index scores. Medical comorbidities are associated with the postoperative complication rate. Managing these comorbidities preoperatively decreases the complications after a spine deformity correction operation. Second, bone densitometry need to be checked for osteoporosis. Many surgical techniques have been introduced to prevent the complications associated with posterior instrumentation for osteoporosis patients. The preoperative use of an osteogenesis inducing agent - teriparatide was also reported to reduce the complication rate. Third, total body sagittal alignment need to be considered. Many elderly spine deformity patients accompanied degenerative changes and deformities at their lower extremities. In addition, a compensation mechanism induces the deformed posture of the lower extremities. Recently, some authors introduced a parameter including total body sagittal alignment, which can predict the clinical outcome better than previous parameters limited to the spine or pelvis. As a result, total body sagittal alignment needs to be considered for elderly spine deformity patients after a deformity correction operation. In conclusion, for elderly spine deformity patients, medical comorbidities and osteoporosis need to be evaluated and managed preoperatively to reduce the complication rate. In addition, total body sagittal alignment needs to be considered, which is associated with better clinical outcomes than the previous parameters limited to the spine or pelvis.