• Imaging Science in Dentistry
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• v.46 no.3
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• pp.203-210
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• 2016

Purpose: The purpose of this study was to investigate appropriate contrast reference values (CRVs) by comparing the contrast in phantom and clinical images. Materials and Methods: Phantom contrast was measured using two methods: (1) counting the number of visible pits of different depths in an aluminum plate, and (2) obtaining the contrast-to-noise ratio (CNR) for 5 tissue-equivalent materials (porcelain, aluminum, polytetrafluoroethylene [PTFE], polyoxymethylene [POM], and polymethylmethacrylate [PMMA]). Four panoramic radiographs of the contrast phantom, embedded in the 4 different regions of the arch-form stand, and 1 real skull phantom image were obtained, post-processed, and compared. The clinical image quality evaluation chart was used to obtain the cut-off values of the phantom CRV corresponding to the criterion of being adequate for diagnosis. Results: The CRVs were obtained using 4 aluminum pits in the incisor and premolar region, 5 aluminum pits in the molar region, and 2 aluminum pits in the temporomandibular joint (TMJ) region. The CRVs obtained based on the CNR measured in the anterior region were: porcelain, 13.95; aluminum, 9.68; PTFE, 6.71; and POM, 1.79. The corresponding values in the premolar region were: porcelain, 14.22; aluminum, 8.82; PTFE, 5.95; and POM, 2.30. In the molar region, the following values were obtained: porcelain, 7.40; aluminum, 3.68; PTFE, 1.27; and POM, - 0.18. The CRVs for the TMJ region were: porcelain, 3.60; aluminum, 2.04; PTFE, 0.48; and POM, - 0.43. Conclusion: CRVs were determined for each part of the jaw using the CNR value and the number of pits observed in phantom images.

• Journal of Gastric Cancer
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• v.21 no.4
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• pp.379-391
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• 2021

Purpose: Promoter DNA methylation of various genes has been associated with metachronous gastric cancer (MGC). The cancer-specific methylation gene, cysteine dioxygenase type 1 (CDO1), has been implicated in the occurrence of residual gastric cancer. We evaluated whether DNA methylation of CDO1 could be a predictive biomarker of MGC using specimens of MGC developing on scars after endoscopic submucosal dissection (ESD). Materials and Methods: CDO1 methylation values (TaqMeth values) were compared between 33 patients with early gastric cancer (EGC) with no confirmed metachronous lesions at >3 years after ESD (non-MGC: nMGC group) and 11 patients with MGC developing on scars after ESD (MGCSE groups: EGC at the first ESD [MGCSE-1 group], EGC at the second ESD for treating MGC developing on scars after ESD [MGCSE-2 group]). Each EGC specimen was measured at five locations (at tumor [T] and the 4-point tumor-adjacent noncancerous mucosa [TAM]). Results: In the nMGC group, the TaqMeth values for T were significantly higher than that for TAM (P=0.0006). In the MGCSE groups, TAM (MGCSE-1) exhibited significantly higher TaqMeth values than TAM (nMGC) (P<0.0001) and TAM (MGCSE-2) (P=0.0041), suggesting that TAM (MGCSE-1) exhibited CDO1 hypermethylation similar to T (P=0.3638). The area under the curve for discriminating the highest TaqMeth value of TAM (MGCSE-1) from that of TAM (nMGC) was 0.81, and using the cut-off value of 43.4, CDO1 hypermethylation effectively enriched the MGCSE groups (P<0.0001). Conclusions: CDO1 hypermethylation has been implicated in the occurrence of MGC, suggesting its potential as a promising MGC predictor.

• The Transactions of the Korean Institute of Power Electronics
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• v.18 no.3
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• pp.232-239
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• 2013

This paper proposes an improved stator flux estimator through ensuring conventional PLPF to act as a pure integrator for sensorless control of induction motors. Conventional PLPF uses the estimated synchronous speed as a cut-off frequency and has the gain and phase compensators. The gain and phase compensators are determined on the assumption that the estimated synchronous angular speed is coincident with the real speed. Therefore, if the synchronous angular speed is not same as the real speed, the gain and phase compensation will not be appropriate. To overcome the problem of conventional PLPF, this paper analyzes the relationship between the synchronous speed error and the phase lag error of the stator flux. Based on the analysis, this paper proposes the synchronous speed error compensation scheme. To achieve a start-up without speed sensor, the current model is used as the stator flux estimator at the standstill. When the motor starts up, the current model should be switched into the voltage model. So a stable transition between the voltage model and the current model is required. This paper proposes the simple transition method which determines the initial values of the voltage model and the current model at the transition moment. The validity of the proposed schemes is proved through the simulation results and the experimental results.

• Journal of Gastric Cancer
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• v.20 no.2
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• pp.202-211
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• 2020

Purpose: This study was to investigate the prognostic significance of the preoperative fibrinogen and systemic inflammation response index (F-SIRI) in a Chinese cohort of resectable gastric cancer. Materials and Methods: Baseline characteristics, preoperative fibrinogen levels and peripheral neutrophil, monocyte, and lymphocyte counts were retrospectively reviewed in 240 patients who underwent radical gastrectomy. The optimal cut-off values for fibrinogen and SIRI were defined as 4.0 g/L and 1.2. Then patients with hyperfibrinogenemia (≥4.0 g/L) and high SIRI (≥1.2) were assigned with an F-SIRI of 2 (both of these hematological abnormalities), 1 (one of these abnormalities), and 0 (neither abnormality), respectively. The prognostic value was examined by univariate and multivariate survival analysis. Results: Preoperative F-SIRI was significantly correlated with tumor size, fibrinogen level, and adjuvant chemotherapy. Whereas there was no significant difference in age, gender, tumor location or other characteristics between groups. In addition, high preoperative F-SIRI was significantly associated with worse disease-free survival (DFS) (hazard ratio [HR], 2.299; 95% confidence interval [CI], 1.482-3.566; P<0.001) and overall survival (OS) (HR, 2.461; 95% CI, 1.584-3.824; P<0.001) by univariate survival analysis. Moreover, it remained an independent predictor for impaired DFS (HR, 2.023; 95% CI, 1.273-3.215; P=0.003) and OS (HR, 2.341; 95% CI, 1.480-3.705; P<0.001) in multivariate Cox regression analysis. Conclusions: Preoperative F-SIRI could serve as a significantly prognostic marker for long-term survival in Chinese patients who underwent radical gastrectomy.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7291-7294
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• 2015

Purpsoe: To investigate the diagnostic value of quantitative analysis of a tissue diffusion and virtual touch tissue imaging quantification (VTIQ) technique with acoustic radiation force impulse (ARFI) elastography for assessing enlarged cervical lymph nodes. Materials and Methods: Fifty-six enlarged cervical lymph nodes confirmed by pathologic diagnoses were covered in the study. According to the results of pathologic diagnosis, patients were classified into benign and malignant groups. All the patients were examined by both conventional ultrasonography and elastography. AREA% and shear wave velocity (SWV) in ROI of different groups were calculated and compared using ROC curves. Cut-off points of AREA% and SWV were determined with receiver operating characteristic curves. Results: Final histopathological results revealed 21 cases of benign and 35 cases of malignant lymph nodes. The mean values of AREA% and SWV in benign and malignant groups were $45.0{\pm}17.9%$ and $2.32{\pm}0.57m/s$, and $61.3{\pm}21.29%$ and $4.36{\pm}1.25$)m/s, respectively. For the parameters of elastography, "AREA%" and SWV demonstrated significant differences between groups (p=0.002). AREA% was positively correlated with SWV with a correlation coefficient of 0.809 (P<0.001). Conclusions: Stiffness of different lymph node diseases in patients may differ. Elastography can evaluate changes sensitively and provide valuable information to doctors. The study proved that the VTIQ elastography technique can play an important role in differential diagnosis of lymph nodes.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.443-446
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• 2012

Purpose: Telomeres play a key role in the maintenance of chromosome integrity and stability, and telomere shortening is involved in initiation and progression of malignancies. The aim of this study was to determine whether telomere length is associated with the colorectal carcinoma. Patients and methods: A total of 148 colorectal cancer (CRC) samples and corresponding adjacent non-cancerous tissues were evaluated for telomere length, P53 mutation, and cyclooxygenase-2 (COX-2) mutation detected by fluorescent immunohistochemistry. Telomere length was estimated by real-time PCR. Samples with a T/S>1.0 have an average telomere length greater than that of the standard DNA; samples with a T/S<1.0 have an average telomere length shorter than that of the standard DNA. Results: Telomeres were shorter in CRCs than in adjacent tissues, regardless of tumor stage and grade, site, or genetic alterations (P=0.004). Telomere length in CRCs also had differences with COX-2 status (P=0.004), but did not differ with P53 status (P=0.101), tumor progression (P=0.244), gender (P=0.542), and metastasis (P=0.488). There was no clear trend between T/S optimal cut-off values (<1 or > 1) and colorectal tumor progression, metastasis, gender, P53 and COX-2 status. Conclusion: These findings suggesting that telomere shortening is associated with colorectal carcinogenesis but does not differ with tumor progression, gender, and metastasis.

• Journal of Preventive Medicine and Public Health
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• v.49 no.1
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• pp.35-44
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• 2016

Objectives: We investigated the associations of sarcopenia-defined both in terms of muscle mass and muscle strength-and sarcopenic obesity with metabolic syndrome. Methods: Secondary data pertaining to 309 subjects (85 men and 224 women) were collected from participants in exercise programs at a health center in a suburban area. Muscle mass was measured using bioelectrical impedance analysis, and muscle strength was measured via handgrip strength. Sarcopenia based on muscle mass alone was defined as a weight-adjusted skeletal muscle mass index more than two standard deviations below the mean of a sex-specific young reference group (class II sarcopenia). Two cut-off values for low handgrip strength were used: the first criteria were <26 kg for men and <18 kg for women, and the second criteria were the lowest quintile of handgrip strength among the study subjects. Sarcopenic obesity was defined as the combination of class II sarcopenia and being in the two highest quintiles of total body fat percentage among the subjects. The associations of sarcopenia and sarcopenic obesity with metabolic syndrome were evaluated using logistic regression models. Results: The age-adjusted risk ratios (RRs) of metabolic syndrome being compared in people with or without sarcopenia defined in terms of muscle mass were 1.25 (95% confidence interval [CI], 1.06 to 1.47, p=0.008) in men and 1.12 (95% CI, 1.06 to 1.19, p<0.001) in women, which were found to be statistically significant relationships. The RRs of metabolic syndrome being compared in people with or without sarcopenic obesity were 1.31 in men (95% CI, 1.10 to 1.56, p=0.003) and 1.17 in women (95% CI, 1.10 to 1.25, p<0.001), which were likewise found to be statistically significant relationships. Conclusions: The associations of sarcopenia defined in terms of muscle mass and sarcopenic obesity with metabolic syndrome were statistically significant in both men and women. Therefore, sarcopenia and sarcopenic obesity must be considered as part of the community-based management of non-communicable diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2037-2041
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• 2015

Background: Relationships between poor prognosis of ovarian malignancies and changes in complete blood count parameters have been proposed previously. In this work, we aimed to evaluate clinicopathologic features in adolescents with adnexal masses and sought to establish any predictive value of the platelet to lymphocyte ratio (PLR) in diagnosis. Materials and Methods: This retrospective study was conducted on 196 adolescent females with adnexal masses. Three groups were constituted with respect to clinical or histopathology results: group 1, non-neoplastic patients (n:65); group 2, neoplastic patients (n:68); and group 3 expectantly managed patients (n:63). The main parameters recorded from the hospital database and patient files were age, body mass index (BMI), chief symptoms, diameter of the mass (DOM), tumor marker levels, complete blood count values including absolute neutrophil, lymphocyte, and platelet counts, mean platelet volume, platelet distribution width, and platecrit, surgical features, and postoperative histopathology results. Results: The expectantly managed patients were younger than the other groups (p=0.007). The mean body mass index (BMI) was higher in the neoplastic group (p=0.016). Preoperative DOM, CA125, mean platelet volume and PLR were statistically significantly different between the groups (p<0.05). ROC curve analysis demonstrated that increased PLR (AUC, 0.609; p=0.011) and BMI (AUC, 0.611; p=0.011) may be discriminative factors in predicting ovarian neoplasms in adolescents preoperatively. When the cut-off point for the PLR level was set to 140, the sensitivity and specificity levels were found to be 65.7% and 57.6%, respectively. Conclusions: We suggest that beside a careful preoperative evaluation including clinical characteristics, ultrasonographic features and tumor markers, PLR may predict ovarian neoplasms in adolescents.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1813-1816
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• 2015

Background: The aim of this study was to research the importance of the neutrophil to lymphocyte ratio (NLR) in prediction of PSA recurrence after radical prostatectomy, which has not been reported so far. Materials and Methods: The data of 175 patients who were diagnosed with localised prostate cancer and underwent retropubic radical prostatectomy was retrospectively examined. Patient pre-operative hemogram parameters of neutrophil count, lymphocyte count and NLR were assessed. The patients whose PSAs were too low to measure after radical prostatectomy in their follow-ups, and then had PSAs of 0,2 ng/mL were considered as patients with PSA recurrence. Patients with recurrence made up Group A and patients without recurrence made up Group B. Results: In terms of the power of NLR value in distinguishing recurrence, the area under OCC was statistically significant (p<0.001) .The value of 2.494 for NLR was found to be a cut-off value which can be used in order to distinguish recurrence according to Youden index. According to this, patients with a higher NLR value than 2.494 had higher rates of PSA recurrence with 89.7% sensitivity and 92.6% specificity. Conclusions: There are certain parameters used in order to predict recurrence with today's literature data.We think that because NLR is easy to use in clinics and inexpensive, and also has high sensitivity and specificity values, it has the potential to be one of the parameters used in order to predict biochemical recurrence in future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.141-150
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• 1988

Damping characteristics of chemically treated solls were studied by the use of FFT Analyzer and Bandwidth method. Also Modal Analysis was performed for the solidified silty sand samples. The soil samples were made of gravelly sand, sand, and silty sand, treated by water-glass chemical grouts. As the result of the study, it was found that the chemical grouting could be used for the vibration diminutinn effect as well as cut-off effect and strength improvement by the fact that the damping ratio of chemically treated soils was highly increased as the damping ratio of solidified soil was 0.11~0.22 and rathier high values in compare with the damping ratio of common soils which was 0.01~0.10.