• Composites Research
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• v.37 no.5
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• pp.402-408
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• 2024

This study evaluates the mechanical performance and thermal analysis characteristics of adhesives exposed to harsh environments, including high temperatures, tap water, and salt water. Pull-out specimens were prepared to investigate changes in adhesive properties under varying temperature, moisture, and salinity conditions. Dynamic mechanical analysis (DMA) was used to measure the glass transition temperature, while field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) were employed to assess microstructural and compositional changes. The results indicate that exposure to different environments induced post-curing, raising the glass transition temperature and enhancing the thermal stability and mechanical performance of the adhesives. Chemical analysis revealed Na and Cl ion penetration in specimens exposed to salt water, suggesting potential long-term degradation. Despite this, pull-out test results showed minimal variation in failure load across different environmental conditions, although microstructural deformation was observed on the adhesive surface after saltwater exposure. These findings provide valuable insights for selecting and applying adhesives in automotive and aerospace components exposed to harsh conditions.

• Journal of the Korean Data and Information Science Society
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• v.21 no.2
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• pp.251-262
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• 2010

While outsourcing has become a basic strategy of the information system adoption, there is an emerging needs to analyze the gap between the required data and the existing data for the new system from an adopting company's perspective. In CRM adoption failure cases, the first reason is adopting company pay no attention to the data that will support investment and systems. So far, there is no attempt to consider data driven approach in information system adoption field. Hence, we propose Information System Adoption Model based on Data (ISAMD) and show how to use in real world by simulation. By using ISAMD, information system adoption decision maker can simulate the needed data and related cost with various information system alternatives in short term, and long term planning. ISAMD can prevent the possible threat of unexpected data cost in adopting new system at the adopting decision stage.

• Korean Journal of Veterinary Research
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• v.64 no.2
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• pp.16.1-16.9
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• 2024

Autologous pericardial tissues are utilized in veterinary cardiovascular surgeries due to their accessibility and effectiveness. To enhance handling and biomechanical properties, glutaraldehyde (GA) fixation is applied. However, GA fixation can induce calcification, leading to tissue failure. This study aimed to establish an optimal rapid anti-calcification protocol by integrating ethanol treatment with the proven effective GA concentration and fixation time, facilitating application from collection to utilization. Pericardia were fixed with 0.625% GA for 20 min and subjected to ethanol treatment for 0 (group A, control), 20 (group B), and 30 minutes (group C). The treated tissues underwent mechanical test and were implanted subcutaneously in 3-week-old male rats for 7 weeks before extraction, followed by calcium analysis and histological examination via hematoxylin and eosin staining. No significant differences in mechanical properties were observed among the groups. The ethanol-treated groups (groups B and C; p < 0.05) exhibited significantly lower calcium levels than control (group A). Microscopy confirmed collagen and elastic fibers preservation, without significant immune cell variance. However, higher fibrocyte presence was noted in the ethanol-treated groups. This study presents a rapid anti-calcification protocol combining ethanol treatment with optimal GA fixation, suitable for direct surgical use of autologous tissues. Further research is necessary for long-term efficacy evaluation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1649-1654
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• 2014

Background: Clinically significant portal hypertension (PHT) is considered as a contraindication for hepatectomy according to the guidelines of the European Association for Study of Liver and the American Association for Study of Liver Diseases. However, this issue remains controversial. Here we performed a metaanalysis to evaluate the impact of PHT on the results of hepatectomy for hepatocellular carcinoma (HCC). Methods: Cohort studies evaluating the impact of clinically significant PHT, defined as oesophageal varices and/or splenomegaly associated with thrombocytopenia, on the results of hepatectomy for HCC were identified using a predefined search strategy. Summary risk ratios (RRs) and 95% confidence intervals (95% CIs) for PHT and outcomes after hepatectomy for HCC were calculated. Results: Seven cohort studies which including 574 cases with PHT and 1,354 cases without PHT were considered eligible for inclusion. The meta-analysis showed that, in all patients, pooled RRs of post-operative liver failure, post-operative ascites, peri-operative blood transfusion, operative mortality, 3- and 5-year overall survival associated with PHT were 2.23 (95% CI: 1.48-3.34, P=0.0001), 1.77 (95% CI: 1.19-2.64, P=0.005), 1.23 (95% CI: 1.03-1.49, P=0.03), 2.58 (95% CI: 1.12-5.96, P=0.03), 0.82 (95% CI: 0.75-0.88, P<0.00001) and 0.76 (95% CI: 0.69-0.85, P<0.00001), respectively. In subgroup analysis, similar results were found in Child-Pugh class A patients. Conclusion: This meta-analysis suggests that presence of oesophageal varices and/or splenomegaly associated with thrombocytopenia is associated with higher rates of post-operative complications and poor long-term survival after hepatectomy for HCC.

• Journal of the Korean Orthopaedic Association
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• v.54 no.5
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• pp.427-434
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• 2019

Purpose: This study evaluated the long term clinical and radiographic results and the survival rates of unicompartmental knee arthroplasty (UKA). In addition, the factors affecting the survival of the procedure were analyzed and the survival curve was compared according to the affecting factors. Materials and Methods: Ninety-nine cases of UKA performed between December 1982 and January 1996 were involved: 10 cases with Modular II, 44 cases with Microloc, and 45 cases with Allegretto prostheses. The mean follow-up period was 16.5 years. Clinically, the hospital for special surgery (HSS) scoring system and the range of motion (ROM) were evaluated. Radiographically, the femorotibial angle (FTA) was measured. The survival rate was analyzed using the Kaplan-Meier method. Cox regression analysis was used to identify the factors affecting the survival according to age, sex, body mass index, preoperative diagnosis, and type of implant. The Kaplan-Meier survival curves were compared according to the factors affecting the survival of UKA. Results: The overall average HSS score and ROM was 57.7 and 134.3° preoperatively, 92.7 and 138.4° at 1 year postoperatively, and 79.1 and 138.4° at the last follow-up (p<0.001, respectively). The overall average FTA was varus 0.8° preoperatively, valgus 4.1° at postoperative 2 weeks, and valgus 3.0° at the last follow-up. The overall 5-, 10-, 15- and 20-year survival rates were 91.8%, 82.9%, 71.0%, and 67.0%, respectively. The factors affecting the survival were the age and type of implant. The risk of the failure decreased with age (hazard ratio=0.933). The Microloc group was more hazardous than the other prostheses (hazard ratio=0.202, 0.430, respectively). The survival curve in the patients below 60 years of age was significantly lower than those of the patients over 60 years of age (p=0.003); the survival curve of the Microloc group was lower compared to the Modular II and Allegretto groups (p=0.025). Conclusion: The long-term clinical and radiographic results and survival of UKA using old fixed bearing prostheses were satisfactory. The selection of appropriate patient and prosthesis will be important for the long term survival of the UKA procedure.

• Healthcare Informatics Research
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• v.24 no.4
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• pp.346-358
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• 2018

Objectives: The association between obstructive sleep apnea (OSA) and mortality or serious cardiovascular events over a long period of time is not clearly understood. The aim of this observational study was to estimate the clinical effectiveness of continuous positive airway pressure (CPAP) treatment on an outcome variable combining mortality, acute myocardial infarction (AMI), and cerebrovascular insult (CVI) during a follow-up period of 15.5 years ($186{\pm}58$ months). Methods: The data set consisted of 978 patients with an apnea-hypopnea index (AHI) ${\geq}5.0$. One-third had used CPAP treatment. For the first time, a data-driven causal Bayesian network (DDBN) and a hypothesis-driven causal Bayesian network (HDBN) were used to investigate the effectiveness of CPAP. Results: In the DDBN, coronary heart disease (CHD), congestive heart failure (CHF), and diuretic use were directly associated with the outcome variable. Sleep apnea parameters and CPAP treatment had no direct association with the outcome variable. In the HDBN, CPAP treatment showed an average improvement of 5.3 percentage points in the outcome. The greatest improvement was seen in patients aged ${\leq}55$ years. The effect of CPAP treatment was weaker in older patients (>55 years) and in patients with CHD. In CHF patients, CPAP treatment was associated with an increased risk of mortality, AMI, or CVI. Conclusions: The effectiveness of CPAP is modest in younger patients. Long-term effectiveness is limited in older patients and in patients with heart disease (CHD or CHF).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.113-118
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• 2021

The guided weapon system should ensure economical operation and user safety. In particular, in the case of guided weapon systems developed in the form of a guaranteed bomb, the standards for maintaining reliability considering the long-term storage environment are presented during the development stage, and an optimized inspection cycle is required to maintain this. This study calculated the reliability through a trend test, fitness test, and distribution analysis using a mathematical model based on the maintenance status and shooting results during the inspection period for OO missiles currently in operation for a long time in the military. Through this, it was applied to the inspection period model (Martinez) set during the development stage to determine if the improved inspection period can be utilized. Finally, by synthesizing the data from these studies, a policy management plan was developed according to the extension of the inspection period. The One-Shot system was operated at the inspection period set when it was developed. The study analyzed the actual failure and maintenance data to reset the efficient inspection period.

• Journal of Korean Neurosurgical Society
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• v.59 no.6
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• pp.637-642
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• 2016

Objective : Although many treatment modalities have been introduced for trigeminal neuralgia (TN), the long-term clinical results remain unsatisfactory. It has been particularly challenging to determine an appropriate treatment strategy for patients who have responded poorly to initial therapies. We analyzed the surgical outcomes in TN patients who failed prior treatments. Methods : We performed a retrospective analysis of 37 patients with recurrent or persistent TN symptoms who underwent surgery at our hospital between January 2010 and December 2014. Patients with follow-up data of at least one year were included. The prior treatment modalities of the 37 patients included microvascular decompression (MVD), gamma knife radiosurgery (GKRS), and percutaneous procedures such as radiofrequency rhizotomy (RFR), balloon compression, and glycerol rhizotomy (GR). The mean follow-up period was 69.9 months (range : 16-173). The mean interval between the prior treatment and second surgery was 26 months (range : 7-123). We evaluated the surgical outcomes using the Barrow Neurological Institute (BNI) pain intensity scale. Results : Among the 37 recurrent or persistent TN patients, 22 underwent MVD with partial sensory rhizotomy (PSR), 8 received MVD alone, and 7 had PSR alone. Monitoring of the surgical treatment outcomes via the BNI pain intensity scale revealed 8 (21.6%) patients with a score of I, 13 (35.1%) scoring II, 13 (35.1%) scoring III, and 3 (8.2%) scoring IV at the end of the follow-up period. Overall, 91.8% of patients had good surgical outcomes. With regard to postoperative complications, 1 patient had transient cerebrospinal fluid rhinorrhea (2.7%), another had a subdural hematoma (2.7%), and facial sensory changes were noted in 8 (21.1%) patients after surgery. Conclusion : Surgical interventions, such as MVD and PSR, are safe and very effective treatment modalities in TN patients who failed initial or prior treatments. We presume that the combination of MVD with PSR enabled us to obtain good short- and long-term surgical outcomes. Therefore, aggressive surgical treatment should be considered in patients with recurrent TN despite failure of various treatment modalities.

• Genomics & Informatics
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• v.20 no.3
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• pp.26.1-26.19
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• 2022

Diabetes and its related complications are associated with long term damage and failure of various organ systems. The microvascular complications of diabetes considered in this study are diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy. The aim is to identify the weighted co-expressed and differentially expressed genes (DEGs), major pathways, and their miRNA, transcription factors (TFs) and drugs interacting in all the three conditions. The primary goal is to identify vital DEGs in all the three conditions. The overlapped five genes (AKT1, NFKB1, MAPK3, PDPK1, and TNF) from the DEGs and the co-expressed genes were defined as key genes, which differentially expressed in all the three cases. Then the protein-protein interaction network and gene set linkage analysis (GSLA) of key genes was performed. GSLA, gene ontology, and pathway enrichment analysis of the key genes elucidates nine major pathways in diabetes. Subsequently, we constructed the miRNA-gene and transcription factor-gene regulatory network of the five gene of interest in the nine major pathways were studied. hsa-mir-34a-5p, a major miRNA that interacted with all the five genes. RELA, FOXO3, PDX1, and SREBF1 were the TFs interacting with the major five gene of interest. Finally, drug-gene interaction network elucidates five potential drugs to treat the genes of interest. This research reveals biomarker genes, miRNA, TFs, and therapeutic drugs in the key signaling pathways, which may help us, understand the processes of all three secondary microvascular problems and aid in disease detection and management.

• Journal of Korean Academy of Nursing
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• v.54 no.3
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• pp.311-328
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• 2024

Purpose: In this study a systematic review and meta-analysis investigated the impact of non-pharmacological interventions on major adverse cardiac events (MACE) in patients with coronary artery disease who underwent percutaneous coronary intervention (PCI). Methods: A literature search was performed using PubMed, Cochrane Library, EMBASE, and Cumulative Index to Nursing & Allied Health Literature databases up to November 2023. The risk of bias was assessed using the Cochrane Risk of Bias 2.0 tool. Effect sizes and 95% confidence intervals were calculated using R software (version 4.3.2). Results: Eighteen randomized studies, involving 2,898 participants, were included. Of these, 16 studies with 2,697 participants provided quantitative data. Non-pharmacological interventions (education, exercise, and comprehensive) significantly reduced the risk of angina, heart failure, myocardial infarction, restenosis, cardiovascular-related readmission, and cardiovascular-related death. The subgroup meta-analysis showed that combined interventions were effective in reducing the occurrence of myocardial infarction (MI), and individual and group-based interventions had significant effects on reducing the occurrence of MACE. In interventions lasting seven months or longer, occurrence of decreased by 0.16 times, and mortality related to cardiovascular disease decreased by 0.44 times, showing that interventions lasting seven months or more were more effective in reducing MI and cardiovascular disease-related mortality. Conclusion: Further investigations are required to assess the cost-effectiveness of these interventions in patients undergoing PCI and validate their short- and long-term effects. This systematic review underscores the potential of non-pharmacological interventions in decreasing the incidence of MACE and highlights the importance of continued research in this area (PROSPERO registration number: CRD42023462690).