Establishment of the Model Widely Valid for the Melting and Vaporization Zones in Selective Laser Melting Printings Via Experimental Verifications

Chang-Shuo Chang,Kuan-Ta Wu,Chang-Fu Han,Tsung-Wen Tsai,Sung-Ho Liu,Jen-Fin Lin 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.1

The thermally affected material properties operating in the three phases and porosity variations in the SS316L steel powder have been introduced to the numerical analyses for the transient volumetric heat source (Q) models developed for the solid powder, melting, and vaporization regions in the selective laser melting (SLM). The bulk Q is thus a function of these heat sources and their ratio defined for the liquid and vapor phases. The heat conduction developed for the solid powders with porosity strings the heat convection with Q as the moving heat source to solve two-dimensional temperature distributions efficiently without the confinement of operating conditions and phase presumption. The specimens with single- and multiple-track printings are prepared to investigate the effects of incident energy density (E) and power intensity (I o) on the geometries of single-track printings and the areal surface roughness (Sa) values of the multiple-track printings with 0 and 50% overlap ratios. Laser power and scanning velocity are the controlling factors for the melting pool depth D and width W . D and W become the governing factors for the keyhole with evaporations, which affects the height H of single track after solidification. The W and D results predicted by the theoretical models developed in this study have an error range, 5–20%, compared to the experimental ones, which is much lower than those reported in the literatures (Gusarov et al. in J Heat Transf 131(7):072101, 2009. https ://doi.org/10.1115/1.31092 45 ; Hussein et al. in Mater Des 52:638–647, 2013. https ://doi.org/10.1016/j.matde s.2013.05.070 ; Yin et al. Int J Adv Manuf Technol 83(9–12): 1847–1859, 2016. https ://doi.org/10.1007/s0017 0-015-7609-x ; Andreotta et al. in Finite Elem Anal Des 135: 36–43, 2017. https ://doi.org/10.1016/j.finel .2017.07.002 ). The contact angle ( ϕ * ) is defined as a function of single-track width ( W ) and solidification height ( H ). ϕ * and Sa are significantly reduced as an E is applied beyond its critical value (47.62–57.14 J/mm 3 ). Significant change in Sa is ascribed to the big difference in the morphology and its surface pattern when E or I o reaches its critical value.

Antioxidation and Antiglycation of 95% Ethanolic Extracts Prepared from the Leaves of Black Nightshade (Solanum nigrum)

Tsung-Han Hou,Jen-Ping Chung,Shang-Shan Chen,Tsu-Liang Chang 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.3

Hyperglycemia results in the formation of advanced glycation end-products (AGE), resulting in an inflammatory response that induces insulin resistance. Evidence indicates that antioxidants can suppress the formation of reactive oxygen species, decrease levels of AGEs by inhibiting glycation. Black nightshade (Solanum nigrum) can be used as a medicinal food for improving blood glucose; however, the identities of the active compounds and how they counteract diabetes remain unknown. This study demonstrate that 95% ethanolic extracts of black nightshade exerted significant antioxidative activity compared with 50% ethanolic extracts and aqueous extracts. Moreover,95% ethanolic extracts of black nightshade produced antiglycative activity, which contributed to the inhibition of fructosamine and generation of α-dicarbonyl compounds. The concentrations of solasonine and solamargine in the 95% ethanolic extracts were 0.484 and 0.183 mg/mg,respectively. These results suggest that black nightshade might serve as a novel source of functional ingredients that exert antiglycation and anti-diabetes activities.

Optimization of Medium Composition for Improving Biomass Production of Lactobacillus plantarum Pi06 Using the Taguchi Array Design and the Box-Behnken Method

Chin-Fa Hwang,Jen-Han Chang,Jer-Yiing Houng,Cheng-Chih Tsai,Chien-Ku Lin,Hau-Yang Tsen 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.4

An immune-enhancing strain, Lactobacillus plantarum Pi06, isolated from a healthy infant was used for biomass production following optimization of the medium in shake-flask culture. Preliminary studies showed that commercial MRS medium and cultivation under static conditions generated higher biomass production than four other tested media with or without a shaking condition. The selected medium composition, consisting of glucose,yeast extract, soy peptone, ammonium citrate, and corn steep liquor, was further optimized using a systematic method that integrated the Taguchi array design and the Box–Behnken method. The response effects of these factors were first investigated using Taguchi design under an L16 (45) array. The suggested medium composition,derived from Statistica 7.1 using the Taguchi design, was applied to cultivate cells and a biomass of 7.16 g dry cell weight (DCW)/L was obtained. Response surface methodology based on the Box–Behnken method for the three response variables of glucose, yeast extract, and corn steep liquor was then used to further increase the biomass level to 8.94 g DCW/L. The resulting optimum medium consisted of 35 g/L glucose, 35 g/L yeast extract, and 40 mL/L corn steep liquor. Compared with the initial medium, the biomass yield was improved from 4.31 to 8.94 g DCW/L, an enhancement of approximately 107%.

The association of ambient air pollution with airway inflammation in schoolchildren.

Chen, Bing-Yu,Chan, Chang-Chuan,Lee, Chung-Te,Cheng, Tsun-Jen,Huang, Wen-Chuan,Jhou, Ji-Ci,Han, Yueh-Ying,Chen, Chu-Chih,Guo, Yue Leon School of Hygiene and Public Health of the Johns H 2012 American Journal of Epidemiology Vol.175 No.8

<P>The biologic mechanisms involved in airway inflammatory response to air pollution are not clearly understood. The authors conducted a longitudinal study to investigate whether exposure to ambient air pollutants affected inflammatory cells and mediators from nasal lavage in schoolchildren. Study participants were 100 elementary and middle-school students in New Taipei City, Taiwan. A structured respiratory health questionnaire was administered in September 2007, followed by monthly measurement of nasal inflammation from October 2007 to November 2009. During the study period, daily concentrations of air pollutants were obtained from the Environmental Protection Administration monitoring station and the Aerosol Supersite. Mixed-effects models were applied to examine the association between air pollution and nasal inflammatory cells and mediators, including percentages of neutrophils, eosinophils, and monocytes in lavaged cells and interleukin-8. A total of 824 measurements were obtained from 100 participants over a period of 10 months. The level of particulate matter with an aerodynamic diameter of 2.5 μm or less (PM(2.5)) was found to be associated with percentage of neutrophils (β = 3.45%, 95% confidence interval: 0.89, 6.01) and interleukin-8 level (β = 29.98 pg/mL, 95% confidence interval: 3.26, 56.69) in the nasal lavage on the day of exposure. In this longitudinal cohort study of schoolchildren, results indicated that exposure to PM(2.5) might induce nasal inflammation.</P>

Comparisons of Moisturizing Function Between Rayon Fabric with Collagen Peptides from Fish Scales and Regular Rayon Fabric Under Various Relative Humidity

Chi‑Shih Huang,Erh‑Jen Hou,Ying‑Chou Lee,Tzong‑Huei Lee,Yi‑Jun Pan,Ta Yu,Wei‑Hsin Lin,Chun‑Han Shih,Wei‑Che Chang 한국섬유공학회 2023 Fibers and polymers Vol.24 No.12

The study was inspired by the specialized facial masks made of rayon non-woven fabrics which contained collagen peptides for improving moisturizing function. This study explored the moisturizing function of a rayon fabric containing collagen peptides extracted from tilapia fish scales under various conditions of relative humidity. This research had implications for the development of clothing that can prevent dry skin. A two-stage nested design experiment was adopted. The first-stage factor such as the fabric has two levels and the second-stage factor such as the relative humidity with three levels nested under each level of the first-stage factor. Preliminary results indicated that introducing a new variable (i.e., fabric moisturizing value, which combines the moisture regains of adsorption and desorption) would be useful. The moisturizing value of the novel rayon fabric and regular rayon fabric increased with the increase in relative humidity, and moisturizing effect of the novel rayon fabric with collagen peptides was better than that of the regular rayon fabric. Therefore, the novel rayon fabric may be suitable for preventing dry skin in winter.

ONYX-II: Efficacy of Ombitasvir/Paritaprevir/Ritonavir + Dasabuvir + Ribavirin in HCV Genotype 1b-Infected Patients with Compensated Cirrhosis from South Korea and Taiwan

( Seung Woon Paik ),( Chi-jen Chu ),( Yan Luo ),( Kwang-hyub Han ),( Jia-horng Kao ),( Jeong Heo ),( Cheng-yuan Peng ),( Yoon Jun Kim ),( Ting-tsung Chang ),( Young-suk Lim ),( Ming Lung Yu ),( Linda 대한간학회 2016 춘·추계 학술대회 (KASL) Vol.2016 No.1

Background: Chronic hepatitis C virus (HCV) infection is associated with development of complications including hepatocellular carcinoma, liver failure and cirrhosis. Patients with cirrhosis are historically more difficult to cure. In southeastern Asia, the most prevalent HCV genotype (GT) is GT1b. In western populations, the 3 direct-acting antiviral (3-DAA) regimen of ombitasvir (OBV), ritonavir-boosted paritaprevir (PTV/r; identified by AbbVie and Enanta) and dasabuvir (DSV) ± ribavirin (RBV) demonstrated sustained virologic response (SVR) at post-treatment week 12 (SVR12) rates of 99% in patients with GT1b infection and compensated cirrhosis regardless of prior treatment experience. The regimen, however, has not been investigated in southeastern Asian populations. The ONYX-II study is evaluating the efficacy and safety of this regimen in Asian patients with HCV GT1b infection and compensated cirrhosis. Methods: Treatment-naive and interferon-based therapy-experienced patients with HCV GT1b-infection and compensated cirrhosis were enrolled in South Korea, Taiwan, and China, and received 12 weeks of OBV/PTV/r (25 mg/150 mg/100 mg once daily) and DSV (250 mg twice daily) with RBV (weight-based). Patients will be followed for 48 weeks after the last dose of study drugs. The primary objectives are to compare the SVR12 rate to the known SVR rate of telaprevir + peg-interferon (IFN) + RBV therapy, and to assess the safety of OBV/PTV/r + DSV + RBV. Results: Twenty-one and 20 subjects were enrolled in South Korea and Taiwan, respectively. Of South Korean patients, 52% were male and 71% were treatment-experienced; of Taiwanese patients, 45% were male and 65% were treatment-experienced. Safety data and SVR at post-treatment week 4 (SVR4) will be available for presentation. Conclusions: The ONYX-II study evaluates the 3-DAA regimen of OBV/PTV/r + DSV with RBV for Asian patients with compensated cirrhosis and HCV GT1b infection. Resultant data may provide evidence for treatment guidelines for HCV GT1b in this population.

GROUND OBSERVATIONS OF SPRITES AND OTHER TLES IN TAIWAN

WANG YUN-CHING,HSU RUE-RON,SU HAN-TZONG,CHEN ALFRED BING-CHIH,LEE YI-JEN,KUO CHENG-LING,TSAY WEAN-SHUN,CHANG CHAN-KAO,WANG SHI-CHUN,LEE LOU-CHUANG,LIU TIE-YUE The Korean Astronomical Society 2005 Journal of The Korean Astronomical Society Vol.38 No.2

Sprites, elves and blue jets are collectively denominated as the upper atmospheric transient luminous events (TLEs). They are recently discovered optical flashes between active thunderstorms and the ionosphere. In this report, a brief introduction to the most important characteristics of TLEs is given. Since 2001, scientists from the National Cheng Kung University have been performing yearly summer campaigns from various locations in Taiwan. The main achievements of their yearly campaign are presented.

A review of rotorcraft Unmanned Aerial Vehicle (UAV) developments and applications in civil engineering

Peter Liu,Albert Y. Chen,Yin-Nan Huang,Jen-Yu Han,Jihn-Sung Lai,Tzong-Hann Wu,Ming-Chang Wen,Meng-Han Tsai,Shih-Chung Kang 국제구조공학회 2014 Smart Structures and Systems, An International Jou Vol.13 No.6

Civil engineers always face the challenge of uncertainty in planning, building, and maintaininginfrastructure. These works rely heavily on a variety of surveying and monitoring techniques. Unmannedaerial vehicles (UAVs) are an effective approach to obtain information from an additional view, andpotentially bring significant benefits to civil engineering. This paper gives an overview of the state of UAVdevelopments and their possible applications in civil engineering. The paper begins with an introduction toUAV hardware, software, and control methodologies. It also reviews the latest developments in technologiesrelated to UAVs, such as control theories, navigation methods, and image processing. Finally, the paperconcludes with a summary of the potential applications of UAV to seismic risk assessment, transportation,disaster response, construction management, surveying and mapping, and flood monitoring and assessment.

A review of rotorcraft Unmanned Aerial Vehicle (UAV) developments and applications in civil engineering

Liu, Peter,Chen, Albert Y.,Huang, Yin-Nan,Han, Jen-Yu,Lai, Jihn-Sung,Kang, Shih-Chung,Wu, Tzong-Hann,Wen, Ming-Chang,Tsai, Meng-Han Techno-Press 2014 Smart Structures and Systems, An International Jou Vol.13 No.6

Civil engineers always face the challenge of uncertainty in planning, building, and maintaining infrastructure. These works rely heavily on a variety of surveying and monitoring techniques. Unmanned aerial vehicles (UAVs) are an effective approach to obtain information from an additional view, and potentially bring significant benefits to civil engineering. This paper gives an overview of the state of UAV developments and their possible applications in civil engineering. The paper begins with an introduction to UAV hardware, software, and control methodologies. It also reviews the latest developments in technologies related to UAVs, such as control theories, navigation methods, and image processing. Finally, the paper concludes with a summary of the potential applications of UAV to seismic risk assessment, transportation, disaster response, construction management, surveying and mapping, and flood monitoring and assessment.

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.