• Korean Journal of Radiology
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• v.21 no.4
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• pp.442-449
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• 2020

Objective: To compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) versus ultrasonography (US) in symptomatic patients with dense breasts, while using histology as the gold standard. Materials and Methods: After obtaining approval from the local ethics board, this prospective study collected data from patients with symptomatic breasts who underwent CESM and US examinations from May 1, 2017 to September 30, 2017. We then selected those with dense breasts and pathological results as our sample population. Both CESM and US results were classified by a radiologist through the Breast Imaging Reporting and Data System, and the results were compared with their corresponding histological results. The chi-square test was conducted to compare the diagnostic performance of CESM and US, and the receiver operating characteristic curves for the two imaging modalities were obtained. Results: A total of 131 lesions from 115 patients with dense breasts were included in this study. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 93.8%, 88.1%, 88.2%, 93.7%, and 90.8% for CESM, and 90.6%, 82.1%, 82.9%, 90.2%, and 86.3% for US, respectively. The p values for sensitivity, specificity, PPV, NPV, and accuracy were 0.687, 0.388, 0.370, 0.702, and 0.238, respectively. The area under the curve of CESM (0.917) was comparable with that of US (0.884); however, the differences between CESM and US were not statistically significant (p = 0.225). Eight false-positive cases and 4 false-negative cases for breast cancer were found in CESM, while 12 false-positive cases and 6 false-negative cases were found in US. Conclusion: The diagnostic performances of CESM and US are comparable in symptomatic women with dense breasts; however, the routine use of additional US imaging is questionable for lesions that can be detected by CESM.

• International Journal of Stem Cells
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• v.15 no.4
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• pp.347-358
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• 2022

Background and Objectives: The search for a suitable alternative for urethral defect is a challenge in the field of urethral tissue engineering. Induced pluripotent stem cells (iPSCs) possess multipotential for differentiation. The in vitro derivation of urothelial cells from mouse-iPSCs (miPSCs) has thus far not been reported. The purpose of this study was to establish an efficient and robust differentiation protocol for the differentiation of miPSCs into urothelial cells. Methods and Results: Our protocol made the visualization of differentiation processes of a 2-step approach possible. We firstly induced miPSCs into posterior definitive endoderm (DE) with glycogen synthase kinase-3𝛽 (GSK3𝛽) inhibitor and Activin A. We investigated the optimal conditions for DE differentiation with GSK3𝛽 inhibitor treatment by varying the treatment time and concentration. Differentiation into urothelial cells, was directed with all-trans retinoic acid (ATRA) and recombinant mouse fibroblast growth factor-10 (FGF-10). Specific markers expressed at each stage of differentiation were validated by flow cytometry, quantitative real-time polymerase chain reaction (qRT-PCR) assay, immunofluorescence staining, and western blotting Assay. The miPSC-derived urothelial cells were successfully in expressed urothelial cell marker genes, proteins, and normal microscopic architecture. Conclusions: We built a model of directed differentiation of miPSCs into urothelial cells, which may provide the evidence for a regenerative potential of miPSCs in preclinical animal studies.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2595-2609
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• 2024

This paper introduces a base isolation system-tuned mass damper inerter (BIS-TMDI) hybrid system to the AP1000 nuclear power plant (NPP), which reduces seismic damage potential of the NPP structure. The effects of fluid-structure interaction (FSI) caused by the passive containment cooling system water storage tank (PCCWST) on NPP's seismic performance are investigated. The FSI of water tank theoretical model is considered based on the Housner's model, and a series of time history analyses are performed to prove the rationality of the proposed model. Three single-objective optimization strategies are employed to minimize the relative displacement variance and absolute acceleration variance of the upper structure, as well as the filtered energy index (FEI). Furthermore, a multi-objective optimization strategy considering all these three indexes is proposed to obtain optimal parameters of vibration control. The influence of vibration control strategies on the relative deformation and acceleration of the upper structure is explored with various water level ratios. The analytical results indicate that the proposed BIS-TMDI strategy has significantly reduced the NPP structure's seismic response. The effectiveness of the vibration control strategy is influenced by the water level ratio, emphasizing the significance of designing an appropriate water level ratio to reduce NPP structure's seismic response.

• Bulletin of the Korean Chemical Society
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• v.27 no.7
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• pp.1083-1085
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• 2006

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.7
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• pp.2339-2355
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• 2021

In this paper, a joint probabilistic data association algorithm based on loss function (LJPDA) is proposed so that the computation load and accuracy of the multi-target tracking algorithm can be guaranteed simultaneously. Firstly, data association is divided in to three cases based on the relationship among validation gates and the number of measurements in the overlapping area for validation gates. Also the contribution coefficient is employed for evaluating the contribution of a measurement to a target, and the loss function, which reflects the cost of the new proposed data association algorithm, is defined. Moreover, the equation set of optimal contribution coefficient is given by minimizing the loss function, and the optimal contribution coefficient can be attained by using the Newton-Raphson method. In this way, the weighted value of each target can be achieved, and the data association among measurements and tracks can be realized. Finally, we compare performances of LJPDA proposed and joint probabilistic data association (JPDA) algorithm via numerical simulations, and much attention is paid on real-time performance and estimation error. Theoretical analysis and experimental results reveal that the LJPDA algorithm proposed exhibits small estimation error and low computation complexity.

• Korean Journal of Materials Research
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• v.33 no.6
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• pp.229-235
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• 2023

An all-perovskite oxide heterostructure composed of SrSnO₃/Nb-doped SrTiO₃ was fabricated using the pulsed laser deposition method. In-plane and out-of-plane structural characterization of the fabricated films were analyzed by x-ray diffraction with θ-2θ scans and φ scans. X-ray photoelectron spectroscopy measurement was performed to check the film's composition. The electrical transport characteristic of the heterostructure was determined by applying a pulsed dc bias across the interface. Unusual transport properties of the interface between the SrSnO₃ and Nb-doped SrTiO₃ were investigated at temperatures from 100 to 300 K. A diodelike rectifying behavior was observed in the temperature-dependent current-voltage (IV) measurements. The forward current showed the typical IV characteristics of p-n junctions or Schottky diodes, and were perfectly fitted using the thermionic emission model. Two regions with different transport mechanism were detected, and the boundary curve was expressed by ln I = -1.28V - 13. Under reverse bias, however, the temperature- dependent IV curves revealed an unusual increase in the reverse-bias current with decreasing temperature, indicating tunneling effects at the interface. The Poole-Frenkel emission was used to explain this electrical transport mechanism under the reverse voltages.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2477-2481
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• 2013

Aims and Background: The purpose of the research was to study the prognostic value of tumor 18F-FDG PET-based parameters in neoadjuvant chemoradiation for patients with squamous esophageal carcinoma. Methods: Sixty patients received chemoradiation therapy followed by esophagectomy and two 18FDG-PET examinations at pre- and post-radiation therapy. PET-based metabolic-response parameters were calculated based on histopathologic response. Linear regression correlation and Cox proportional hazards models were used to determine prognostic value of all PET-based parameters with reference to overall survival. Results: Sensitivity (88.2%) and specificity (86.5%) of a percentage decrease of SUVmax were better than other PET-based parameters for prediction of histopathologic response. Only percentage decrease of SUVmax and tumor length correlated with overall survival time (linear regression coefficient ${\beta}$: 0.704 and 0.684, P<0.05). The Cox proportional hazards model indicated higher hazard ratio (HR=0.897, P=0.002) with decrease of SUVmax compared with decrease of tumor size (HR=0.813, P=0.009). Conclusion: Decrease of SUVmax and tumor size are significant prognostic factors in chemoradiation of esophageal carcinoma.

• The Korean Journal of Community Living Science
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• v.24 no.4
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• pp.447-456
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• 2013

This study was conducted to find out the weight control experiences, body image perception and eating disorder status of high school students in Yantai City, Shandong Province, China. The subjects of the study were 457 high school students in Yantai City. The results were as follows. The ratio of underweight and overweight and obesity of the subjects were 20.0% and 12.6% respectively. And 35% of the subjects had weight control experiences. There were significant differences according to the students' gender, location and BMI. In body image perception, the subjects who were normal and underweight overestimated their body figure, and the subjects who were overweight and obese underestimated their body figure. The girls wanted to have extremely skinny figure than standard figure and the degree of dissatisfactions with their figure was high. In the case of overweight and obese students, it showed a high degree of dissatisfaction of their body image. The ratio of the eating disorder group and eating disorder risk group were 7% and 19.3%, Compared to the students in rural areas, downtown students had significantly higher ratio of eating disorder. In conclusion, the education of healthy body weight and body image is necessary to the students in Yantai City, China. Especially the female students who live in downtown are considered to be the most important subjects of nutrition education.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2005.09a
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• pp.136-147
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• 2005

The inhibitor, a kind of ethyl acetate crude extract, was isolated from the old culture liquid of I.galbana. Through measured the culture density, the contents of chlorophyll a. polysaccharide and protein in the cells, the inhibitory effect of the inhibitor on the growth of cells was investigated. The results showed that the inhibitor obviously inhibited the cell growth of three microalgae.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1769-1772
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• 2011