Microstructure and Mechanical Properties of (TiZrHf)50(NiCoCu)50 High Entropy Alloys

Chih‑Hsuan Chen,Yue‑Jin Chen,Jia‑Jyun Shen 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.5

The microstructure and mechanical properties of pseudo-binary (TiZrHf)50(NiCoCu)50 high entropy alloys(HEAs) with B2 matrix were investigated in this study. The studied HEAs includes Ti40Zr10Ni40Co5Cu5,Ti30Zr20Ni30Co10Cu10,Ti25Zr25Ni16.67Co16.67Cu16.67,Ti30Zr10Hf10Ni30Co10Cu10,Ti20Zr15Hf15Ni20Co15Cu15,andTi16.67Zr16.67Hf16.67Ni16.67Co16.67Cu16.67. XRD and SEM analyses revealed that all studied HEAs were a mixture of B2 andC15 intermetallic phases, instead of a single solid solution, due to their highly negative enthalpy of mixing and the relativelylarge difference in atomic radii. The B2 matrix was found capable of forming a solid solution of all six elements in a widecomposition range. The lattice constants of B2 and C15 phases increase linearly with increasing the difference in atomicradii. Additionally, the microhardness of these HEAs increases from 409 to 595 HV with the increasing difference in atomicradii as well. Compression tests demonstrated substitution of Zr with Hf can improve the ductility. In all studied HEAs, theTi30Zr10Hf10Ni30Co10Cu10HEA achieves a great balance between yield strength, ultimate compressive strength, and fracturestrain of 1574 MPa, 1933 MPa, and 6.5%, respectively.

Comparison of Cortical Bone Trajectory to Pedicle-Based Dynamic Stabilization: An Analysis of 291 Patients

Chih-Chang Chang,Hsuan-Kan Chang,Chin-Chu Ko,Ching-Lan Wu,Yi-Hsuan Kuo,Tsung-Hsi Tu,Wen-Cheng Huang,Jau-Ching Wu 대한척추신경외과학회 2023 Neurospine Vol.20 No.1

Objective: Pedicle-based dynamic stabilization (DS) has gained popularity outside of America. Although pedicle screw (PS) loosening has always been a concern, it is reportedly innocuous. Cortical bone trajectory (CBT) screw is an emerging option with less invasiveness and similar effectiveness to PS in short-segment lumbar fusion. This study aimed to verify the use of CBT for DS by comparing the outcomes between pedicle- and CBT-based DS. Methods: Consecutive patients with lumbar spondylosis or low-grade spondylolisthesis who underwent 1- or 2-level DS between L3–5 with a minimum follow-up of 24 months were reviewed. Screw loosening was determined by computed tomography and the incidences were compared. Results: A total of 291 patients who underwent Dynesys DS (235 pedicle- and 56 CBT-based, respectively) were compared. The demographics and preoperative conditions were similar. All the clinical outcomes improved at 24-month postoperation, while the CBT-based group had less operation time and blood loss than the pedicle-based group. The rates of screw loosening were lower in the CBT-based (5.4% per screw and 12.5% per patient) than the pedicle-based group (9% per screw and 26.4% per patient). Furthermore, there were no differences in the clinical outcomes and complication profiles. Conclusion: The CBT-based DS for 1- or 2-level lumbar degeneration demonstrated equivalent clinical improvement as the pedicle-based DS. The adaption of CBT-based screws for DS could be a less invasive approach (shorter operation time and less blood loss), with lower chances of screw loosening than the conventional PS-based DS.

Effect of Landslide Deposition on Soil Properties in the Xitou Experiment Forest, Central Taiwan

Chih-Hsin Cheng,Sheng-Che Hsiao,Yu-Hsuan Huang,Chih-Yu Hung,Chuang-Wen Pai,Chiu Ping Chen,Oleg Menyailo 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Measurement of Deformity at the Craniovertebral Junction: Correlation of Triangular Area and Myelopathy

Chih-Chang Chang,Jau-Ching Wu,Chin-Chu Ko,Hsuan-Kan Chang,Yi-Hsuan Kuo,Chao-Hung Kuo,Tsung-Hsi Tu,Wen-Cheng Huang 대한척추신경외과학회 2022 Neurospine Vol.19 No.4

Objective: Diseases of the craniovertebral junction (CVJ) are commonly associated with deformity, malalignment, and subsequent myelopathy. The misaligned CVJ might cause compression of neuronal tissues and subsequently clinical symptoms. The triangular area (TA), measured by magnetic resonance imaging/images (MRI/s), is a novel measurement for quantification of the severity of compression to the brain stem. This study aimed to assess the normal and pathological values of TA by a comparison of patients with CVJ disease to age- and sex-matched controls. Moreover, postoperative TAs were correlated with outcomes. Methods: Consecutive patients who underwent surgery for CVJ disease were included for comparison to an age- and sex-matched cohort of normal CVJ persons as controls. The demographics, perioperative information, and pre- and postoperative 2-year cervical MRIs were collected for analysis. Cervical TAs were measured and compared. Results: A total of 201 patients, all of whom had pre- or postoperative MRI, were analyzed. The TA of the CVJ deformity group was larger than the healthy control group (1.62 ± 0.57 cm2 vs. 1.01 ± 0.18 cm2 , p < 0.001). Moreover, patients who had combined anterior odontoidectomy and posterior laminectomy with fixation had the greatest reduction in the TA (1.18 ± 0.58 cm2 ). Conclusion: In CVJ deformity, the measurement of the cervical TA could indicate the severity of brain stem compression. After surgery, the TA had a varying degree of improvement, which could represent the efficacy of surgery.

Invited Papers : Is IFRS Related to Lower IPO Valuation Error?

( Hsuan Chu Lin ),( She Chih Chiu ),( Shih Han Chuang ) 한국회계학회 2015 會計學硏究 Vol.40 No.2

This study compares the accuracies in IPO valuation under International Financial Reporting Standards (IFRS) and under U.S. Generally Accepted Accounting Principle (US GAAP). This study conducts comparable-firms approach with a sample of recent IPOs in the US capital market during 2005-2013. The IPOs are grouped into three sub-samples: (1) IFRS adopters, (1) US GAAP adopters, (2) US GAAP adopters, and (3) Local GAAP adopters. The findings show that IFRS adopters exhibit prediction errors smaller than other adopters in the IPO valuation. In addition, IFRS adopters among the adopters provide financial reporting users with higher predict value than other accounting standards after the IPO. The findings remain robust after additional checks. Overall, the findings are supportive to the viewpoint that IFRS is conducive to the quality of accounting information and financial statement users`` investment decisions. However, several limitations in this study are also mentioned.

Quantitative phosphoproteomic analysis identifies the potential therapeutic target EphA2 for overcoming sorafenib resistance in hepatocellular carcinoma cells

Chih-Ta Chen,Li-Zhu Liao,Ching-Hui Lu,Yung-Hsuan Huang,Yu-Kie Lin,Jung-Hsin Lin,Lu-Ping Chow 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Limited therapeutic options are available for advanced-stage hepatocellular carcinoma owing to its poor diagnosis. Drug resistance to sorafenib, the only available targeted agent, is commonly reported. The comprehensive elucidation of the mechanisms underlying sorafenib resistance may thus aid in the development of more efficacious therapeutic agents. To clarify the signaling changes contributing to resistance, we applied quantitative phosphoproteomics to analyze the differential phosphorylation changes between parental and sorafenib-resistant HuH-7 cells. Consequently, an average of ~1500 differential phosphoproteins were identified and quantified, among which 533 were significantly upregulated in resistant cells. Further bioinformatic integration via functional categorization annotation, pathway enrichment and interaction linkage analysis led to the discovery of alterations in pathways associated with cell adhesion and motility, cell survival and cell growth and the identification of a novel target, EphA2, in resistant HuH-7R cells. In vitro functional analysis indicated that the suppression of EphA2 function impairs cell proliferation and motility and, most importantly, overcomes sorafenib resistance. The attenuation of sorafenib resistance may be achieved prior to its development through the modulation of EphA2 and the subsequent inhibition of Akt activity. Binding analyses and in silico modeling revealed a ligand mimic lead compound, prazosin, that could abate the ligand-independent oncogenic activity of EphA2. Finally, data obtained from in vivo animal models verified that the simultaneous inhibition of EphA2 with sorafenib treatment can effectively overcome sorafenib resistance and extend the projected survival of resistant tumor-bearing mice. Thus our findings regarding the targeting of EphA2 may provide an effective approach for overcoming sorafenib resistance and may contribute to the management of advanced hepatocellular carcinoma.

Lattice Relations and Solidification of the Complex Regular Eutectic (Cr,Fe)-(Cr,Fe)23C6

Hsuan-Han Lai,Chih-Chun Hsieh,Chi-Ming Lin,Weite Wu 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.3

The eutectic (Cr,Fe)-(Cr,Fe)23C6 showed a triaxial fishbone structure and could be categorized as a “complexregular structure”. In this study, the lattice relations of the fishbone (Cr,Fe)23C6 were examined and the solidificationprocess was observed using a transmission electron microscope and a confocal laser scanning microscope. Forone of the three fish bones in a eutectic cell, parallel (Cr,Fe)23C6 lamellas at one side of the spine had the samelattice direction, as did those in the (Cr,Fe) phase. The lattices of neighboring (Cr,Fe)23C6 and (Cr,Fe) phases werenot coherent. Lamellar (Cr,Fe)23C6 on opposite sides of a spine had different lattice directions, and their latticeboundary was in the spine. By using the confocal laser scanning microscope, the solidification of lamellar eutecticstructure could be observed. At the low cooling rate of 5oC·min-1, parallel lamellas would grow thick blocksinstead of thin plates. To obtain a thin lamellar eutectic structure, the cooling rate should be higher, likethe rate in welding.

Effects of Vanadium Content on the Microstructure and Dry Sand Abrasive Wear of a Eutectic Cr-Fe-C Hardfacing Alloy

Hsuan-Han Lai,Chih-Chun Hsieh,Chi-Ming Lin,Weite Wu 대한금속·재료학회 2016 METALS AND MATERIALS International Vol.22 No.1

In this study, the effects of vanadium on the morphology and wear behavior of a eutectic Cr-Fe-C hardfacing alloy were discussed. The alloys tested contained different amounts of vanadium, ranging from 0 to 2.39 wt%. A fibrous V4C3 was found when the alloy contained 0.93 wt% vanadium. The addition of vanadium was found to decrease the fraction of eutectic M23C6 and increase the width of the interspaces between the eutectic cells. The DTA results revealed that V4C3 formed just before the eutectic α+M23C6 during solidification. The surface hardness was shown to increase with increasing vanadium content, which also caused the hardness deviation and wear loss to decrease; however, the addition of vanadium was not shown to affect the hardness of eutectic α+M23C6. The V4C3 could be scratched off during the wear test due to the increase in the width of the interspaces between the eutectic cells; therefore, the alloys that contained 0.93 and 2.39 wt% vanadium exhibited similar wear loss results.

Design and Implementation of a Two-Switch Buck-Boost Typed Inverter with Universal and High-Efficiency Features

Chien-Hsuan Chang,Chun-An Cheng,En-Chih Chang,Hung-Liang Cheng 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

A typical photovoltaic (PV) grid-connection power system is usually consisted of multi-stage converters to perform multiple functions simultaneously. In order to simplify system configuration, reduce cost, and improve conversion efficiency, this paper proposes to adopt two-switch buck-boost (TSBB) dc-dc converters, and then develops families of buck-boost typed inverters via the connection with an H-bridge unfolding circuit with linecommuted operation. The proposed inverters have both step-up and step-down functions so that they are suitable for the applications with wide voltage-variation range. Depending on the conditions of dc input-voltage and ac output-voltage, the proposed circuits can work functionally as either buck-typed or boost-typed inverter. Due to operating with buck or boost principle, partial energy can be directly delivered to output to improve efficiency. Besides, since only one power switch operates with high-frequency, switching losses can be reduced significantly. Finally, one of the proposed TSBB inverters, named buck-cascaded buck-boost (BuCBB) inverter, is then implemented accordingly to generate 110 Vrms / 60 Hz output voltage. Experimental results have verified the validity of theoretical predictions and the feasibility of proposed inverters.

Virtual Screening and Testing of GSK-3 Inhibitors Using Human SH-SY5Y Cells Expressing Tau Folding Reporter and Mouse Hippocampal Primary Culture under Tau Cytotoxicity

Lin Chih-Hsin,Hsieh Yu-Shao,Sun Ying-Chieh,Huang Wun-Han,Chen Shu-Ling,Weng Zheng-Kui,Lin Te-Hsien,Wu Yih-Ru,Chang Kuo-Hsuan,Huang Hei-Jen,Lee Guan-Chiun,Hsieh-Li Hsiu Mei,Lee-Chen Guey-Jen 한국응용약물학회 2023 Biomolecules & Therapeutics(구 응용약물학회지) Vol.31 No.1

Glycogen synthase kinase-3β (GSK-3β) is an important serine/threonine kinase that implicates in multiple cellular processes and links with the neurodegenerative diseases including Alzheimer’s disease (AD). In this study, structure-based virtual screening was performed to search database for compounds targeting GSK-3β from Enamine’s screening collection. Of the top-ranked compounds, 7 primary hits underwent a luminescent kinase assay and a cell assay using human neuroblastoma SH-SY5Y cells expressing Tau repeat domain (TauRD) with pro-aggregant mutation ΔK280. In the kinase assay for these 7 compounds, residual GSK-3β activities ranged from 36.1% to 90.0% were detected at the IC50 of SB-216763. In the cell assay, only compounds VB-030 and VB-037 reduced Tau aggregation in SH-SY5Y cells expressing ΔK280 TauRD-DsRed folding reporter. In SH-SY5Y cells expressing ΔK280 TauRD, neither VB-030 nor VB-037 increased expression of GSK-3α Ser21 or GSK-3β Ser9. Among extracellular signal-regulated kinase (ERK), AKT serine/threonine kinase 1 (AKT), mitogen-activated protein kinase 14 (P38) and mitogenactivated protein kinase 8 (JNK) which modulate Tau phosphorylation, VB-037 attenuated active phosphorylation of P38 Thr180/ Tyr182, whereas VB-030 had no effect on the phosphorylation status of ERK, AKT, P38 or JNK. However, both VB-030 and VB-037 reduced endogenous Tau phosphorylation at Ser202, Thr231, Ser396 and Ser404 in neuronally differentiated SH-SY5Y expressing ΔK280 TauRD. In addition, VB-030 and VB-037 further improved neuronal survival and/or neurite length and branch in mouse hippocampal primary culture under Tau cytotoxicity. Overall, through inhibiting GSK-3β kinase activity and/or p-P38 (Thr180/Tyr182), both compounds may serve as promising candidates to reduce Tau aggregation/cytotoxicity for AD treatment.