• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.306.1-306.1
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• 2007

• Structural Engineering and Mechanics
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• v.49 no.2
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• pp.273-283
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• 2014

According to deformation features of pre-twisted bar, its elastic bending and torsion buckling equation is developed in the paper. The equation indicates that the bending buckling deformations in two main bending directions are coupled with each other, bending and twist buckling deformations are coupled with each other as well. However, for pre-twisted bar with dual-axis symmetry cross-section, bending buckling deformations are independent to the twist buckling deformation. The research indicates that the elastic torsion buckling load is not related to the pre-twisted angle, and equals to the torsion buckling load of the straight bar. Finite element analysis to pre-twisted bar with different pre-twisted angle is performed, the prediction shows that the assumption of a plane elastic bending buckling deformation curve proposed in previous literature (Shadnam and Abbasnia 2002) may not be accurate, and the curve deviates more from a plane with increasing of the pre-twisting angle. Finally, the parameters analysis is carried out to obtain the relationships between elastic bending buckling critical capacity, the effect of different pre-twisted angles and bending rigidity ratios are studied. The numerical results show that the existence of the pre-twisted angle leads to "resistance" effect of the stronger axis on buckling deformation, and enhances the elastic bending buckling critical capacity. It is noted that the "resistance" is getting stronger and the elastic buckling capacity is higher as the cross section bending rigidity ratio increases.

• The korean journal of orthodontics
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• v.53 no.2
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• pp.125-136
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• 2023

Before progress was recently made in the application of temporary anchorage devices (TADs) in bio-mechanical design, orthodontists were rarely able to intrude molars to reduce upper posterior dental height (UPDH). However, TADs are now widely used to intrude molars to flatten the occlusal plane or induce counterclockwise rotation of the mandible. Previous studies involving clinical or animal histological evaluation on changes in periodontal conditions after molar intrusion have been reported, however, studies involving human histology are scarce. This case was a Class I malocclusion with a high mandibular plane angle. Upper molar intrusion with TADs was performed to reduce UPDH, which led to counterclockwise rotation of the mandible. After 5 months of upper molar intrusion, shortened clinical crowns were noticed, which caused difficulties in oral hygiene and hindered orthodontic tooth movement. The mid-treatment cone-beam computed tomography revealed redundant bone physically interfering with buccal attachment and osseous resective surgeries were followed. During the surgeries, bilateral mini screws were removed and bulging alveolar bone and gingiva were harvested for biopsy. Histological examination revealed bacterial colonies at the bottom of the sulcus. Infiltration of chronic inflammatory cells underneath the non-keratinized sulcular epithelium was noted, with abundant capillaries being filled with red blood cells. Proximal alveolar bone facing the bottom of the gingival sulcus exhibited active bone remodeling and woven bone formation with plump osteocytes in the lacunae. On the other hand, buccal alveolar bone exhibited lamination, indicating slow bone turnover in the lateral region.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1661-1668
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• 2016

A fixed off-time controlled high power factor ac-dc LED driver is proposed in this paper, which employs a novel zero-crossing-compensation (ZCC) circuit based on a fixed off-time controlled scheme. Due to the parasitic parameters of the system, the practical waveforms have a dead region. By detecting the zero-crossing boundary, the proposed ZCC circuit compensates the control signal VCOMP within the dead region, and is invalid above this region. With further optimization of the parameters KR and Kτ of the ZCC circuit, the dead zone can be eliminated and lower THD is achieved. Finally, the chip is implemented in HHNEC 0.5μm 5V/40V HVCMOS process, and a prototype circuit, delivering 7~12W of power to several 3-W LED loads, is tested under AC input voltage ranging from 85V to 265V. The test results indicate that the average total harmonic distortion (THD) of the entire system is approximately 10%, with a minimum of 5.5%, and that the power factor is above 0.955, with a maximum of 0.999.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.63-66
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• 2008

Anthracene is a PAH that is not readily degraded, plus its degradation mechanism is still not clear. Thus, two strains of anthracene-degrading bacteria were isolated from long-term petroleum-polluted soil and identified as Sphingomonas sp. 12A and Pseudomonas sp. 12B by a 16S rRNA sequence analysis. To further enhance the anthracene-degrading ability of the two strains, the biosurfactants produced by Pseudomonas aeruginosa $W_3$ were used, which were characterized as rhamnolipids. It was found that these rhamnolipids dramatically increased the solubility of anthracene, and a reverse-phase HPLC assay showed that the anthracene degradation percentage after 18 days with Pseudomonas sp. 12B was significantly enhanced from 34% to 52%. Interestingly, their effect on the degradation by Sphingomonas sp. 12A was much less, from 35% to 39%. Further study revealed that Sphingomonas sp. 12A also degraded the rhamnolipids, which may have hampered the effect of the rhamnolipids on the anthracene degradation.

• Journal of Power Electronics
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• v.16 no.3
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• pp.840-848
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• 2016

A primary-side regulation AC-DC converter operating in the PFM (Pulse Frequency Modulation) mode with a high precision output current is designed, which applies a novel inductance compensation technique to improve the precision of the output current, which reduces the bad impact of the large tolerance of the transformer primary side inductance in the same batch. In this paper, the output current is regulated by the OSC charging current, which is controlled by a CC (constant current) controller. Meanwhile, for different primary inductors, the inductance compensation module adjusts the OSC charging current finely to improve the accuracy of the output current. The operation principle and design of the CC controller and the inductance compensation module are analyzed and illustrated herein. The control chip is implemented based on a TSMC 0.35μm 5V/40V BCD process, and a 12V/1.1A prototype has been built to verify the proposed control method. The deviation of the output current is within ±3% and the variation of the output current is less than 1% when the inductances of the primary windings vary by 10%.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.27-31
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• 2012

Objectives: Expression of vascular endothelial growth factor C (VEGF-C)and vascular endothelial growth factor feceptor-3 (VEGFR-3) in laryngeal squamous carcinoma and its relationship to lymph node metastasis were investigated. Methods: VEGF-C and VEGFR-3 gene expression in 30 cases of normal laryngeal mucosa tissue (NLM), primary laryngeal carcinoma cell carcinomas (PLC) and cervical lymph nodes (CLN) was examined by reverse transcription polymerase chain reaction (RT-PCR). Protein levels of VEGF-C expression were determined by immunohistochemical staining in 60 cases of PLC. Results: Expression of VEGF-C and VEGFR-3 different among NLM, PLC and CLN in the same patient. In PLC, expression was significantly higher in lymph node positive group than in the lymph node negative group and associated with histological grade of differentiation; Expression of VEGF-C and VEGFR-3 was not linked with age, sex, site or T stage. Conclusions: A close correlation was found between VEGF-C/VEGFR-3 expression and lymph node metastasis in PLC, suggesting a role in metastasis of laryngeal carcinomas.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1651-1655
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• 2012

Background: Our aim was to investigate the efficacy of the Pap test in combination with the ThinPrep cytological test (TCT) in screening for cervical cancer in China. Design: From March 2006 to October 2008, 988 women with the mean age $46.4{\pm}10.5$ years (range, 23-80 years) were recruited to receive cervical cancer screening. Pap test results ${\geq}$ grade III and TCT findings ${\geq}$ ASCUS/AGUS were considered abnormal. Subjects with a Pap test result ${\geq}$ grade IIb received TCT. Colposcopy and biopsies were performed in all participants, and final diagnosis was based on pathological findings. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and Youden index for predicting CIN I or above were determined. Results: The sensitivity, specificity, PPV, NPV and Youden index of the Pap test were 43.1%, 97.2%, 70.0%, 91.9%, and 40.3%, respectively. The same values for TCT in predicting CIN were 80.0%, 63.2%, 16.0%, 97.3%, and 43.2%, respectively. The two tests in combination gave values for predicting CIN of 64.8%, 87.6%, 43.6%, 94.4%, and 53.5%, respectively. Combined testing exhibited the highest Youden index (53.4%). Conclusion: The Pap test with a reduced threshold in combination with the TCT has high sensitivity and high specificity in screening for cervical cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.85-91
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• 2014

Background: Genome-wide association studies (GWAS) have identified various genetic susceptibility loci for breast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns exist between European and Asian populations. Methods: Ten SNPs (rs2075555 in COL1A1, rs12652447 in FBXL17, rs10941679 in 5p12/MRPS30, rs11878583 in ZNF577, rs7166081 in SMAD3, rs16917302 in ZNF365, rs311499 in 20q13.3, rs1045485 in CASP8, rs12964873 in CDH1 and rs8170 in 19p13.1) were here genotyped in 1009 Chinese females (487 patients with breast cancer and 522 control subjects) using the Sequenom MassARRAY iPLEX platform. Association analysis based on unconditional logistic regression was carried out to determine the odds ratio (OR) and 95% confidence interval (95% CI) for each SNP. Stratification analyses were carried out based on the estrogen receptor (ER) and progesterone receptor (PR) status. Results: Among the 10 SNPs, rs10941679 showed significant association with breast cancer when differences between the case and control groups in this Han Chinese population were compared (30.09% GG, 45.4% GA and 23.7% AA; P = 0.012). Four SNPs (rs311499, rs1045485, rs12964873 and rs8170) showed no polymorphisms in our study. The remaining five SNPs showed no association with breast cancer in the present population. Immunohistochemical tests showed that rs2075555 was associated with ER status; the AA genotype showed greater association with ER negative than ER positive (OR = 0.54, 95% CI, 0.29-0.99; P = 0.046). AA of rs7166081 was also associated with ER status, but showed a greater association with ER positive than negative (OR = 1.59, 95% CI = 1.04-2.44; P = 0.031). However, no significant associations were found among the SNPs and PR status. Conclusion: In this study using a Han Chinese population, rs10941679 was the only SNP associated with breast cancer risk, indicating a difference between European and Chinese populations in susceptibility loci. Therefore, confirmation studies are necessary before utilization of these loci in Chinese.

• Animal Bioscience
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• v.35 no.2
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• pp.281-289
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• 2022

Objective: The aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk. Methods: Potential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4℃. Results: Two EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period. Conclusion: This study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk.