Effect of ethyl alcohol aging on the apatite formation of a low-modulus Ti-7.5Mo alloy treated with aqueous NaOH

Ho, Wen-Fu,Tsou, Hsi-Kai,Wu, Shih-Ching,Hsu, Shih-Kuang,Chuang, Shao-Hsuan,Hsu, Hsueh-Chuan Techno-Press 2014 Biomaterials and biomedical engineering Vol.1 No.1

The purpose of this experiment was to evaluate the apatite-formation abilities of low-modulus Ti-7.5Mo substrates treated with NaOH aqueous solutions and subsequent ethyl alcohol aging before soaking them in simulated body fluid. Specimens of Ti-7.5Mo were initially treated with 5 M NaOH at $60^{\circ}C$ for 24 h, resulting in the formation of a porous network structure composed of sodium hydrogen titanate. Afterwards, the specimens were aged in ethyl alcohol at $60^{\circ}C$ for 5 or 10 min, and subsequently immersed in simulated body fluid at $37^{\circ}C$ for 3, 7 and 14 days. Ethyl alcohol aging significantly increased the apatite-forming abilities of Ti-7.5Mo. The amount of apatite deposited on the Ti-7.5Mo after NaOH treatment and subsequent ethyl alcohol aging was much greater, especially after the Ti-7.5Mo specimens were aged for 5 min. Due to its excellent combination of bioactivity, low elastic modulus and low processing costs, the Ti-7.5Mo treated with NaOH aqueous solutions and subsequently aged in ethyl alcohol has promising heavy load-bearing applications.

Effect of ethyl alcohol aging on the apatite formation of a low-modulus Ti-7.5Mo alloy treated with aqueous NaOH

Ho, Wen-Fu,Tsou, Hsi-Kai,Wu, Shih-Ching,Hsu, Shih-Kuang,Chuang, Shao-Hsuan,Hsu, Hsueh-Chuan Techno-Press 2014 Biomaterials and Biomechanics in Bioengineering Vol.1 No.1

The purpose of this experiment was to evaluate the apatite-formation abilities of low-modulus Ti-7.5Mo substrates treated with NaOH aqueous solutions and subsequent ethyl alcohol aging before soaking them in simulated body fluid. Specimens of Ti-7.5Mo were initially treated with 5 M NaOH at $60^{\circ}C$ for 24 h, resulting in the formation of a porous network structure composed of sodium hydrogen titanate. Afterwards, the specimens were aged in ethyl alcohol at $60^{\circ}C$ for 5 or 10 min, and subsequently immersed in simulated body fluid at $37^{\circ}C$ for 3, 7 and 14 days. Ethyl alcohol aging significantly increased the apatite-forming abilities of Ti-7.5Mo. The amount of apatite deposited on the Ti-7.5Mo after NaOH treatment and subsequent ethyl alcohol aging was much greater, especially after the Ti-7.5Mo specimens were aged for 5 min. Due to its excellent combination of bioactivity, low elastic modulus and low processing costs, the Ti-7.5Mo treated with NaOH aqueous solutions and subsequently aged in ethyl alcohol has promising heavy load-bearing applications.

Hydroxyapatite prepared from eggshell and mulberry leaf extract by precipitation method

Wu, Shih-Ching,Hsu, Hsueh-Chuan,Hsu, Shih-Kuang,Liu, Mei-Yi,Ho, Wen-Fu Techno-Press 2019 Biomaterials and Biomechanics in Bioengineering Vol.4 No.1

Eggshell is a waste material after the usage of egg. In this work, biowaste chicken eggshells were used for preparing carbonated hydroxyapatite (HA) nanoparticles of high purity through aqueous precipitation method at room temperature. The eggshell-derived HA will be a cost-effective bioceramics for biomedical applications and an effective material-recycling technology. Additionally, mulberry leaf extract was used as a template to regulate the morphology, size and crystallinity of HA, and the effects of pH value were also examined. Characterization of the samples was performed by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Scanning electron microscopy (SEM) was used to determine the size, shape and morphology of HA. The results indicate that only one phase of HA were synthesized in the both absence and presence of mulberry leaf extract at pH of 7 and above, while DCPD or DCPA/DCPD phase was observed at pH 4 condition. The crystallite sizes of the HA samples obviously decreased when adding mulberry leaf extract as a template, while they decreased gradually as the solution pH levels increased. With increasing pH level from 7 to 14, the rod-like HA nanoparticles gradually changed to spherical shape at pH 14. Note that, the obtained product is Mg and Sr containing A- and B-type carbonate HA at alkaline pH and it can be a potential material for biomedical applications.

Psilocybin for End-of-Life Anxiety Symptoms: A Systematic Review and Meta-Analysis

Chia-Ling Yu,Fu-Chi Yang,Szu-Nian Yang,Ping-Tao Tseng,Brendon Stubbs,Ta-Chuan Yeh,Chih-Wei Hsu,Dian-Jeng Li,Chih-Sung Liang 대한신경정신의학회 2021 PSYCHIATRY INVESTIGATION Vol.18 No.10

Objective To systematically examine the effectiveness and tolerability of psilocybin for treating end-of-life anxiety symptoms. Methods The Medline, Embase, CENTRAL, and PsycINFO databases were searched up to November 25, 2020. We enrolled clinical trials investigating psilocybin for treating end-of-life anxiety symptoms. Meta-analysis was conducted using random-effects model. Results Overall, five studies were included, revealing that psilocybin was superior to the placebo in treating state anxiety at 1 day (Hedges’ g, -0.70; 95% confidence interval, -1.01 to -0.39) and 2 weeks (-1.03; -1.47 to -0.60) after treatment. Psilocybin was more effective than placebo in treating trait anxiety at 1 day (-0.71; -1.15 to -0.26), 2 weeks (-1.08; -1.80 to -0.36), and 6 months (-0.84; -1.37 to -0.30) after treatment. Psilocybin was associated with transient elevation in systolic (19.00; 13.58-24.41 mm Hg) and diastolic (8.66; 5.18-12.15 mm Hg) blood pressure compared with placebo. The differences between psilocybin and placebo groups with regard to allcause discontinuation, serious adverse events, and heart rates were nonsignificant. Conclusion Psilocybin-assisted therapy could ameliorate end-of-life anxiety symptoms without serious adverse events. Because of the small sample sizes of the included studies and high heterogeneity on long-term outcomes, future randomized controlled trials with large sample sizes are needed.

Characterization of nanosized hydroxyapatite prepared by an aqueous precipitation method using eggshells and mulberry leaf extract

Wu Shih-Ching,Hsu Hsueh-Chuan,Liu Mei-Yi,Ho Wen-Fu 한국세라믹학회 2021 한국세라믹학회지 Vol.58 No.1

Hydroxyapatite (HA) has been vigorously studied for orthopedic and dental applications due to its excellent bioactivity, osteoconductivity, and osteoinductivity. This study aims to present a simple room-temperature aqueous precipitation method for obtaining carbonated HA nanoparticles of high purity from biowaste chicken eggshells. Biowaste chicken eggshells were used for preparing HA through aqueous precipitation method. Moreover, mulberry leaf extract was used as a template to regulate the morphology, size, and crystallinity of HA. All produced nanocrystalline HA powders exhibited rod-like particle agglomerates of a size below 100 nm. The HA particles synthesized with the mulberry leaf extract showed higher crystallinity and slightly decreased crystallite sizes compared to the samples prepared without adding the extract. Carbonate peaks observed for the specimens closely matched those of A- and B-type carbonates, which can contribute to the low crystallinity. Notably, the HA synthesized from the eggshell powders contains several important trace elements such as Mg and Sr, which are benefi cial to the overall biological performance as biomaterials. The morphology, size, structure, and composition of the obtained HA products are similar to those of natural bones, and consequently, the products show potential as a material for biomedical applications.

Novel Metastable Nonequiatomic Ti-Zr-Nb-Mo Medium-Entropy Alloys with High Yield-Strength-to-Elastic-Modulus Ratios

Ka‑Kin Wong,Hsueh‑Chuan Hsu,Shih‑Ching Wu,Wen‑Fu Ho 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.10

In this study, novel nonequiatomic Ti-rich Ti-Zr-Nb-Mo medium-entropy alloys (Ti-MEAs) with a metastable body-centeredcubic structure were designed using Mo equivalent theory ([Mo]eq) for biomedical applications. The Ti65-Zr20-Nb14-Mo1(at%; Ti65-M1) and Ti65-Zr18-Nb16-Mo1 (at%; Ti65-M2) exhibited high yield strength of 1188 and 1118 MPa, respectively. Notably, the moduli of Ti65-M1 and Ti65-M2 were as low as 67.4 and 61 GPa, respectively, which were considerably lowerthan those of commercial biomedical alloys and several biomedical HEAs/MEAs. Transmission electron microscopy imagesindicated that Ti65-M2 reached a metastable state, resulting in a low elastic modulus. Furthermore, the yield-strength-to-elastic-modulus ratios (× 1000) of Ti65-M1 and Ti65-M2 were as high as 17.6 and 18.3, respectively, which were approximatelythree times greater than that of a commercial Ti-6Al-4V ELI implant. This study applied metastable theory for developingtwo metastable Ti-MEAs with low elastic moduli.

Inverse Analysis of Inconel 718 Laser-Assisted Milling to Achieve Machined Surface Roughness

Yixuan Feng,Tsung-Pin Hung,Yu-Ting Lu,Yu-Fu Lin,Fu-Chuan Hsu,Chiu-Feng Lin,Ying-Cheng Lu,Xiaohong Lu,Steven Y. Liang 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.11

This manuscript proposes an inverse analysis method for the machined surface roughness in laser-assisted milling on Inconel 718. The method solves the forward problem considering the tool profile and the elastic recovery of machined surface and applies the variance-based recursive method to guide the updating mechanism of process parameters to match the measurements. Subsequently, the inverse analysis identifies four process parameters of feed per tooth, tool tip radius, minimum cutting thickness, and tool tip angle, and finds the optimal solution for target performance, the surface roughness. The measurements are collected under the single beam coaxial laser-assisted milling spindle. The proposed modified Kalman filter algorithm introduces the gain coefficient G when updating the process parameters to improve robustness and accuracy. The inverse analysis is conducted on all measurements, and the average error of target performance is 0.460% when the laser is on and 0.394% when the laser is off. The average difference of process parameters is less than 5%, and the selection process is done in 50 loops within a minute. Therefore, the proposed inverse analysis model is robust, adaptive to different initial guesses and measurements, highly accurate, and saves computation time.