Uniaxial Compression Properties and Compression Fatigue Performance of Selective Laser Melted Ti–6Al–4V Cellular Structure

Ming‑Wei Wu,Jhewn‑Kuang Chen,Mo‑Kai Tsai,Pei Wang,Tien‑Lin Cheng,Bo‑Huan Lin,Po‑Hsing Chiang,Annadurai Dhinakar 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.1

The selective laser melted (SLM) Ti–6Al–4V cellular solid is a promising material in biomedical and other applications. The mechanical properties of the SLM Ti–6Al–4V cellular material are predominantly controlled by the design of the cellular structure. The objective of this study was to investigate the uniaxial compressive properties and compressive fatigueperformance of the SLM Ti–6Al–4V cellular solid with a new cuboctahedron unit cell reinforced by four diagonal strutsand two horizontal struts along the X and Y axes. The infuences of hot isostatic pressing (HIP) on the various mechanicalproperties were also examined. The results showed a smoother stress–strain curve and fewer stress oscillations in the HIPspecimen than in the SLM specimen. The HIP process slightly decreased the yield strength of the SLM sample from 55 to52 MPa. Under uniaxial compressive stress, the SLM and HIP specimens exhibited layer-by-layer fracture and diagonalshear fracture, respectively. Furthermore, the HIP treatment signifcantly increased the fatigue performance and improved thefatigue endurance ratio at 106cycles from 0.15 to 0.35. The HIP treatment contributed to several positive efects, includingphase transformation from brittle α′ to α + β, the elimination of strut porosity and residual stress, an increase in lath size,and a better combination of strength and ductility, thereby improving the fatigue performance. The efects of stress mode onthe fracture mechanism were also clarifed using in situ observation in combination with digital image correlation.

Mechanism underlying 2n male and female gamete formation in lemon via cytological and molecular marker analysis

Kai‑Dong Xie,Qiang‑Ming Xia,Jun Peng,Xiao‑Meng Wu,Zong‑Zhou Xie,Chun‑Li Chen,Wen‑Wu Guo 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.2

The unreduced (2n) gametes have long been used in triploid breeding of citrus. In lemon, the previously reported mechanisms for 2n megagametophyte formation were controversial, whereas that for 2n pollen production is still unknown. Herein, the frequency of and mechanism underlying 2n megagametophyte and 2n pollen formation in ‘Eureka’ lemon were investigated based on cytological observation and genotyping of the triploid hybrids between ‘Eureka’ lemon and ‘Early gold’ sweet orange. As a result, 4.79% of the viable pollens of ‘Eureka’ lemon were identified as the 2n pollen with a larger diameter (70.16 ± 3.92 μm). The 2n pollen might be resulted from the formation of parallel spindles at meiosis stage II. Among the 204 plantlets regenerated from embryo rescue following the sexual cross, 12 were triploids as identified by flow cytometry. According to the analysis of heterozygosity transmission using 13 pericentromeric single nucleotide polymorphism (SNP) markers and 20 randomly distributed simple sequence repeat (SSR) markers, 11 triploids were identified to be originated from the fertilization of 2n megagametophytes of ‘Eureka’ lemon, with a frequency of 5.39%. Among them, nine 2n megagametophytes were supposed to be arisen from the second division restitution (SDR), whereas the other two were from postmeiotic genome doubling (PMD). These results to understand the mechanism underlying 2n gamete formation in lemon are valuable for its efficient polyploid breeding.

Microstructures, Mechanical Properties, and Fracture Behaviors of Metal-Injection Molded 17-4PH Stainless Steel

Ming-Wei Wu,Zeng-Kai Huang,Chun-Feng Tseng,Kuen-Shyang Hwang 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.3

Metal injection molding (MIM) is a versatile technique for economically manufacturing various metal parts with complicated shapes and excellent properties. The objective of this study was to clarify the effects of powder type (water-atomized and gas-atomized powders) and various heat treatments (sintering, solutioning, H900, and H1100) on the microstructures, mechanical properties, and fracture behaviors of MIM 17- 4PH stainless steels. The results showed that better mechanical properties of MIM 17-4PH can be achieved with gas-atomized powder than with water-atomized powder due mainly to the lower silicon and oxygen contents and fewer SiO2 inclusions in the steels. The presence of 10 vol% δ ferrite does not impair the UTS or elongation of MIM 17-4PH stainless steels. The δ ferrite did not fracture, even though the neighboring martensitic matrix was severely cracked. Moreover, H900 treatment produces the highest hardness and UTS, along with moderate elongation. H1100 treatment produces the best elongation, along with moderate hardness and UTS.

International Young Doctors` Session : Session 3 ; Monozygotic twinning after IVF/ICSI treatment: the first single-center experience in Taiwan

( Dennis Wu ),( Shang Yu Huang ),( Hsien Ming Wu ),( Chun Kai Chen ),( Yung Kuei Soong ),( Hong Yuan Huang ) 대한산부인과학회 2013 서울심포지움 Vol.18 No.-

Development of Novel Tool Center Point Velocity Planning Algorithm for Five Axis Machine Tool

Shih-Kai Wu,Meng-Shiun Tsai,Ming-Tzong Lin,Hong-Wei Huang 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.8

In this paper, a tool center point (TCP) feedrate scheduling algorithm for 5-axis machine tool is developed to generate the axes interpolation commands. The proposed algorithm considers not only the constraints of TCP velocity, acceleration and jerk, but also the velocity differences of each axes at the junction of each block. First, the proposed method determines the maximum speed for each block segment at the TCP coordinate based on the computed length. Then the kinematics of the five axis machine tool is employed to derive the five-axis corner velocity difference (FCVD) formulation. The FCVD utilizes the axis velocity difference at the junction of blocks as the designed variable. As the starting and end velocities of each block are determined, the S-shape acceleration/ deceleration (Acc/Dec) method is adopted to generate both smooth TCP and rotary axis profile based on the given interpolation parameters. The servo dynamics of the five axis machine tool are utilized to evaluate the performances of the FCVD. Simulation results demonstrate that the FCVD can achieve better contour accuracy with less machining time as compared to the five-axis feedrate regulation formulation (FFRF) algorithm. Furthermore, the FCVD are compared with Heidenhain CNC controller and the results show that the FCVD has similar behaviors as the Heidenhain controller, but it can achieve less machining time.

Comparison of Serum Ketone Levels and Cardiometabolic Efficacy of Dapagliflozin versus Sitagliptin among Insulin-Treated Chinese Patients with Type 2 Diabetes Mellitus

Chi-Ho Lee,Mei-Zhen Wu,David Tak-Wai Lui,Darren Shing-Hei Chan,Carol Ho-Yi Fong,Sammy Wing-Ming Shiu,Ying Wong,Alan Chun-Hong Lee,Joanne King-Yan Lam,Yu-Cho Woo,Karen Siu-Ling Lam,Kelvin Kai-Hang Yiu 대한당뇨병학회 2022 Diabetes and Metabolism Journal Vol.46 No.6

Background: Insulin-treated patients with long duration of type 2 diabetes mellitus (T2DM) are at increased risk of ketoacidosis related to sodium-glucose co-transporter 2 inhibitor (SGLT2i). The extent of circulating ketone elevation in these patients remains unknown. We conducted this study to compare the serum ketone response between dapagliflozin, an SGLT2i, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, among insulin-treated T2DM patients.Methods: This was a randomized, open-label, active comparator-controlled study involving 60 insulin-treated T2DM patients. Participants were randomized 1:1 for 24-week of dapagliflozin 10 mg daily or sitagliptin 100 mg daily. Serum β-hydroxybutyrate (BHB) levels were measured at baseline, 12 and 24 weeks after intervention. Comprehensive cardiometabolic assessments were performed with measurements of high-density lipoprotein cholesterol (HDL-C) cholesterol efflux capacity (CEC), vibration-controlled transient elastography and echocardiography.Results: Among these 60 insulin-treated participants (mean age 58.8 years, diabetes duration 18.2 years, glycosylated hemoglobin 8.87%), as compared with sitagliptin, serum BHB levels increased significantly after 24 weeks of dapagliflozin (P=0.045), with a median of 27% increase from baseline. Change in serum BHB levels correlated significantly with change in free fatty acid levels. Despite similar glucose lowering, dapagliflozin led to significant improvements in body weight (P=0.006), waist circumference (P=0.028), HDL-C (P=0.041), CEC (P=0.045), controlled attenuation parameter (P=0.007), and liver stiffness (P=0.022). Average E/e’, an echocardiographic index of left ventricular diastolic dysfunction, was also significantly lower at 24 weeks in participants treated with dapagliflozin (P=0.037).Conclusion: Among insulin-treated T2DM patients with long diabetes duration, compared to sitagliptin, dapagliflozin modestly increased ketone levels and was associated with cardiometabolic benefits.

Tazarotene-Induced Gene 1 Enhanced Cervical Cell Autophagy through Transmembrane Protein 192

Shyu, Rong-Yaun,Wang, Chun-Hua,Wu, Chang-Chieh,Chen, Mao-Liang,Lee, Ming-Cheng,Wang, Lu-Kai,Jiang, Shun-Yuan,Tsai, Fu-Ming Korean Society for Molecular and Cellular Biology 2016 Molecules and cells Vol.39 No.12

Tazarotene-induced gene 1 (TIG1) is a retinoic acid-inducible protein that is considered a putative tumor suppressor. The expression of TIG1 is decreased in malignant prostate carcinoma or poorly differentiated colorectal adenocarcinoma, but TIG1 is present in benign or well-differentiated tumors. Ectopic TIG1 expression led to suppression of growth in cancer cells. However, the function of TIG1 in cell differentiation is still unknown. Using a yeast two-hybrid system, we found that transmembrane protein 192 (TMEM192) interacted with TIG1. We also found that both TIG1A and TIG1B isoforms interacted and co-localized with TMEM192 in HtTA cervical cancer cells. The expression of TIG1 induced the expression of autophagy-related proteins, including Beclin-1 and LC-3B. The silencing of TMEM192 reduced the TIG1-mediated upregulation of autophagic activity. Furthermore, silencing of either TIG1 or TMEM192 led to alleviation of the upregulation of autophagy induced by all-trans retinoic acid. Our results demonstrate that the expression of TIG1 leads to cell autophagy through TMEM192. Our study also suggests that TIG1 and TMEM192 play an important role in the all-trans retinoic acid-mediated upregulation of autophagic activity.

Effect of Vanadium on the Microstructure and Mechanical Properties of 2100 MPa Ultra-High Strength High Plasticity Spring Steel Processed by a Novel Online Rapid-Induction Heat Treatment

Qi‑Lei Dai,Kun Li,Kai‑Ren Meng,Zhou Fang,Wen Chen,Tian‑Bao Yang,Chi Feng,Jin‑Ming Wu,R. D. K. Misra 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.4

Advanced automotive industries generate large demand for the next generation of high strength and high toughness springsteels. Vanadium-containing 55SiCrV spring steels subjected to rapid-induction heating treatment can fulfil such requirements. However, the effect of vanadium microalloying under online rapid-induction heat treatments is rarely reported. Acomparative study of the microstructure and tensile properties of 55SiCr and 55SiCrV spring steel wires subjected to a novelonline rapid induction heat treatment has been demonstrated herein. It is found that the tensile strength of the 55SiCr springwire decreases with the decrease in the wire speed in online rapid-induction heating, and the plasticity increases. Whereas,the tensile strength of the 55SiCrV steel wire increases with the decrease in the wire speed with the retained high plasticity,which is attributed to the strengthening effect of the dislocations. Through the optimized rapid-induction heating/coolingthermal cycles and intermediate-temperature tempering treatment, the tensile strength of the 55SiCrV steel wire approaches2106 MPa with total elongation of 9.7%. Compared with the 55SiCr spring steel, the addition of V in 55SiCrV spring steelchanges the strengthening and toughening mechanisms via the grain refinement and enhancement in the hardenability andtempering resistance. The finely dispersed V-containing secondary phases are rarely found in the matrix, which indicates thatthe precipitation effect stemming from the addition of V is not the dominant strengthening factor in the online rapid-inductionheat process. The proposed novel online rapid-induction heat treatment provides a promising pathway for the mechanicalproperty improvement of the spring steel.

Tazarotene-Induced Gene 1 Interacts with DNAJC8 and Regulates Glycolysis in Cervical Cancer Cells

Wang, Chun-Hua,Shyu, Rong-Yaun,Wu, Chang-Chieh,Chen, Mao-Liang,Lee, Ming-Cheng,Lin, Yi-Yin,Wang, Lu-Kai,Jiang, Shun-Yuan,Tsai, Fu-Ming Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.6

The tazarotene-induced gene 1 (TIG1) protein is a retinoidinducible growth regulator and is considered a tumor suppressor. Here, we show that DnaJ heat shock protein family member C8 (DNAJC8) is a TIG1 target that regulates glycolysis. Ectopic DNAJC8 expression induced the translocation of pyruvate kinase M2 (PKM2) into the nucleus, subsequently inducing glucose transporter 1 (GLUT1) expression to promote glucose uptake. Silencing either DNAJC8 or PKM2 alleviated the upregulation of GLUT1 expression and glucose uptake induced by ectopic DNAJC8 expression. TIG1 interacted with DNAJC8 in the cytosol, and this interaction completely blocked DNAJC8-mediated PKM2 translocation and inhibited glucose uptake. Furthermore, increased glycose uptake was observed in cells in which TIG1 was silenced. In conclusion, TIG1 acts as a pivotal repressor of DNAJC8 to enhance glucose uptake by partially regulating PKM2 translocation.

Changes in prostate-specific antigen kinetics during androgen-deprivation therapy as a predictor of response to abiraterone in chemonaïve patients with metastatic castration-resistant prostate cancer

Chung-Lin Lee,Ying-Hsu Chang,Chung-Yi Liu,Ming-Li Hsieh,Liang-Kang Huang,Yuan-Cheng Chu,Hung-Cheng Kan,Po-Hung Lin,Kai-Jie Yu,Cheng-Keng Chuang,Chun-Te Wu,See-Tong Pang,I-Hung Shao 대한비뇨의학회 2022 Investigative and Clinical Urology Vol.63 No.5

Purpose: Metastatic castration-resistant prostate cancer (mCRPC) has a poor prognosis. Abiraterone acetate (AA), enzalutamide, and chemotherapy are first-line treatments for patients with mCRPC. This study examined prognostic factors for AA response in the form of prostate-specific antigen (PSA) kinetics throughout androgen-deprivation therapy (ADT) in chemonaïve patients with mCRPC. Materials and Methods: We retrospectively included data from 34 chemonaïve patients with mCRPC who had received AA at some point between January 2017 and December 2018. We separated patients into two study arms according to the decrease in PSA percentages after use of AA for 3 months. We correlated PSA kinetics parameters with response and compared the two study groups with respect to PSA kinetics. Results: The patients’ median age was 77 years. In the total group of patients, 64% had a response to AA, whereas 35% did not. The ratio of the PSA level at nadir to the level during ADT was significantly higher in the AA-sensitive group (19.78 vs. 1.03, p=0.019). Conclusions: Patients who experienced a dramatic change in PSA level during ADT were more likely to be resistant to AA after progression to mCRPC. Chemotherapy rather than AA might be more suitable as a first-line treatment for these patients.