Effect of Welding Processes on Corrosion Resistance of UNS S31803 Duplex Stainless Steel

( Liu Ho Chiu ),( Wen Chin Hsieh ) 한국부식방식학회 2003 Corrosion Science and Technology Vol.2 No.1

Metabolism of Safrole, a Betel Quid Component, and its Role in the Development of Oral Cancer in Taiwan

Liu, Tsung-Yun,Chen, Chiu-Lan,Chung, Yu-Ting,Chi, Chin-Wen The Korean Society of Toxicology Korea Environment 2001 Toxicological Research Vol.17 No.-

Chewing betel quid is associated with an increased risk of oral cancer. The betel quid chewed in Taiwan includes the inflorescence of Piper betle, which contains high concentrations of safrole (15 mg/fresh weight). Piper betle leaf is also used in betel quid; however, the concentration of safrole in betel leaf has not been documented. Chewing betel quid may contribute to safrole exposure in man (420 mm in saliva). Using $a^{32}$P-postlabeling method, we have recently demonstrated the presence of stable safrole-like DNA adducts in human oral tissues following betel quid chewing. Safrole is a rodent hepatocar-cinogen, and the real nature of safrole-DNA adducts in human tissues beside oral has not been elucidated. In this paper, we tested the safrole DNA adducts forming potential in human hepatic and oral derived cells by the ${32}^P$-postlabeling technique. The results suggest that oral cancer derived cell OC-2 alone is not able to form safrole-DNA adduct. However, safrole DNA adducts can be detected following I'-hydroxysafrole, a proximate safrole metabolite, treatment. In addition, pretreament of cytochrome P450 inducers also enhanced the formation of previously undetectable safrole DNA adducts. This finding couples with our previous results suggest that oral may serve as a target tissue for safrole, and safrole may be involved in oral carcinogenesis.

Studies on Lao-Chao Culture Filtrate for a Flavoring Agent in a Yogurt-Like Product

Liu, Yi-Chung,Chen, Ming-Ju,Lin, Chin-Wen Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.4

Lao-chao is a traditional Chinese fermented rice product with a sweet and fruity flavor, containing high levels of glucose, a little alcohol and milk-clotting characteristics. In order to optimize commercial production of lao-chao, Rhizopus javanicus and Saccharomyces cerevisiae were selected as the mold and yeast starter, respectively. A commercial mixed starter (chiu-yao) was used as control. Fermentation of the experimental combination revealed a sharp drop in pH (to 4.5) on the fourth day, remaining constant thereafter. Content of reducing sugars gradually decreased throughout the entire fermentation period. Of the free amino acids, higher quantities of alanine, leucine, proline, glutamic acid, glutamine and $NH_3$ were noted. For sugars, glucose revealed the highest concentration, while organic acid levels, including those for oxalic, lactic, citric and pyroglutamic acid, increased throughout the fermentation period. Twenty-one compounds were identified by gas chromatography from aroma concentrates of the lao-chao culture filtrate, prepared using the headspace method. For the flavor components, higher quantities of ethanol, fusel oil and ester were determined in both culture filtrates. In regard to the evaluation of yogurt-like product, there were significant differences in alcoholic smell, texture and curd firmness.

Antioxidative Activities of Kefir

Liu, Je-Ruei,Lin, Yuh-Yih,Chen, Ming-Ju,Chen, Li-Ju,Lin, Chin-Wen Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.4

This study aims to evaluate the antioxidative activities of cow-milk kefir and goat-milk kefir. Antioxidative mechanisms, including radical-scavenging effects, ferrous-ion chelating ability, reducing power and antioxidant activity, were investigated herein. Kefirs demonstrated significantly greater scavenging effects upon 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide radicals, an inhibition effect upon linoleic-acid peroxidation, and more substantial reducing power, but reduced glutathione peroxidase (GSH-Px) activity than was the case for milks. There was no significant difference between milks and kefirs as regards ferrous-ion chelating ability and superoxide dismutase (SOD) activity. These findings have demonstrated that kefirs possess antioxidant activity, thereby suggesting that kefirs are potential candidates for the role of useful natural antioxidant supplements for the human diet.

Measurement of Active Power Using an Optical Fiber Grating

Chin-Hsing Cheng,Li-Min Lin,Wen-Fung Liu 한국자기학회 2008 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Effect of Vacuum Brazing on Corrosion Resistance of SAF 2205 and Superdex 64 Duplex Stainless Steel

Hsieh, Wen-Chin,Chiu, Liu-Ho,Ling, Yi-Chun 한국부식방식학회 2002 Corrosion Science and Technology Vol.31 No.2

Duplex stainless steel has a combination of better mechanical strength and pitting corrosion resistance, but the precipitated brittle phase as б phase formed during the cooling from the welding procedure will rapidly degrade its properties. In order to avoid the precipitation of secondary phases in the welds, the effect of vacuum brazing on the properties of the welds of UNS S31803 (SAF 2205) and UNS S31200 (SuperDux64) duplex stainless steels has been investigated. Three fillers, such as copper foil, BNi-3 and BNi-7 Ni-based alloy, were used to evaluate the influence of chemical composition on the corrosion resistance. In air quench, a cooling rate of 0.85℃/s and the precipitation of б phase can be inhibited for those studied duplex stainless steels. Under the quenched state, the weight loss of UNS S31803 DSS dipped in 6%FeCl₃ solution at 45℃ for 24 hours is low. However, the precipitation of a phase in UNS S31803 was increased as the cooling rate decreased. When the cooling rate was decreased to 0.067℃/s, the weight loss of UNS S31803 was increased. Owing to the compositional difference between the filler and duplex stainless steel, the selective corrosion occurred at the interface of brazed joints soaked in 6% FeCl₃ solution for 24 hours.

Enhancement of Aggregation-Induced Emission in Dye-Encapsulating Polymeric Micelles for Bioimaging

Wu, Wen-Chung,Chen, Ching-Yi,Tian, Yanqing,Jang, Sei-Hum,Hong, Yuning,Liu, Yang,Hu, Rongrong,Tang, Ben Zhong,Lee, Yi-Ting,Chen, Chin-Ti,Chen, Wen-Chang,Jen, Alex K.-Y. WILEY-VCH Verlag 2010 Advanced Functional Materials Vol.20 No.9

<P>Three amphiphilic block copolymers are employed to form polymeric micelles and function as nanocarriers to disperse hydrophobic aggregation-induced emission (AIE) dyes, 1,1,2,3,4,5-hexaphenylsilole (HPS) and/or bis(4-(N-(1-naphthyl) phenylamino)-phenyl)fumaronitrile (NPAFN), into aqueous solution for biological studies. Compared to their virtually non-emissive properties in organic solutions, the fluorescence intensity of these AIE dyes has increased significantly due to the spatial confinement that restricts intramolecular rotation of these dyes and their better compatibility in the hydrophobic core of polymeric micelles. The effect of the chemical structure of micelle cores on the photophysical properties of AIE dyes are investigated, and the fluorescence resonance energy transfer (FRET) from the green-emitting donor (HPS) to the red-emitting acceptor (NPAFN) is explored by co-encapsulating this FRET pair in the same micelle core. The highest fluorescence quantum yield (∼62%) could be achieved by encapsulating HPS aggregates in the micelles. Efficient energy transfer (>99%) and high amplification of emission (as high as 8 times) from the NPAFN acceptor could also be achieved by spatially confining the HPS/NPAFN FRET pair in the hydrophobic core of polymeric micelles. These micelles could be successfully internalized into the RAW 264.7 cells to demonstrate high-quality fluorescent images and cell viability due to improved quantum yield and reduced cytotoxicity.</P> <B>Graphic Abstract</B> <P>Highly efficient fluorescence probes are achieved through the encapsulation of aggregation-induced emission molecules, 1,1,2,3,4,5-hexaphenylsilole (HPS) and/or bis(4-(N-(1-naphthyl) phenylamino)-phenyl)fumaronitrile (NPAFN) in the core of polymeric micelles. Bright fluorescence cell images are shown with tunable colors of green directly from HPS aggregates and red through efficient fluorescence resonance energy transfer (FRET) from HPS aggregates to NPAFN aggregates. <img src='wiley_img_2010/1616301X-2010-20-9-ADFM200902043-content.gif' alt='wiley_img_2010/1616301X-2010-20-9-ADFM200902043-content'> </P>

Exendin-4 improves resistance to Listeria monocytogenes infection in diabetic db/db mice

Hsien Yueh Liu,Chih-Yao Chung,Wen-Chin Yang,Chih-Lung Liang,Chi-Young Wang,Chih-Yu Chang,Cicero Lee-Tian Chang 대한수의학회 2012 Journal of Veterinary Science Vol.13 No.3

The incidence of diabetes mellitus is increasing among companion animals. This disease has similar characteristics in both humans and animals. Diabetes is frequently identified as an independent risk factor for infections associated with increased mortality. In the present study, homozygous diabetic (db/db) mice were infected with Listeria (L.) monocytogenes and then treated with the anti-diabetic drug exendin-4, a glucagon-like peptide 1 analogue. In aged db/db mice, decreased CD11b+ macrophage populations with higher lipid content and lower phagocytic activity were observed. Exendin-4 lowered high lipid levels and enhanced phagocytosis in macrophages from db/db mice infected with L. monocytogenes. Exendin-4 also ameliorated obesity and hyperglycemia, and improved ex vivo bacteria clearance by macrophages in the animals. Liver histology examined during L. monocytogenes infection indicated that abscess formation was much milder in exendin-4-treated db/db mice than in the control animals. Moreover, mechanistic studies demonstrated that expression of ATP binding cassette transporter 1, a sterol transporter, was higher in macrophages isolated from the exendin-4-treated db/db mice. Overall, our results suggest that exendin-4 decreases the risk of infection in diabetic animals by modifying the interaction between intracellular lipids and phagocytic macrophages.

Unusual Exchange Bias Effects Induced in NiFe/Mn Thin Films via Ion-beam Bombardment: Superlattice vs. Nanocomposite

Chi-Hsin Liu,Chin Shueh,Tien-Chi Lan,Ko-Wei Lin,Wen-Chen Chen,Te-Ho Wu,R. D. Desautels,J. van Lierop 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.12

The interplay between interlayer coupling and exchange bias coupling in [NiFe/Mn] multilayerbasedthin films was investigated by using ion-beam bombardment during deposition to control theconfigurations from superlattice to nanocomposite or hybrid-structured thin films. Results showedthat well-defined interfaces in the superlattice [NiFe/Mn] thin film exhibited an interlayer couplingbehavior. In contrast, an enhanced coercivity was observed in the nanocomposite [NiFe-Mn] thinfilm. However, the hybrid [NiFe-Mn]/[NiFe/Mn] thin film with an intermixed NiFeMn alloyed filmcomponent gave rise to unusual positive exchange bias coupling.

Epidemiology and risk factors associated with avascular necrosis in patients with autoimmune diseases: a nationwide study

( Hsin-lin Tsai ),( Jei-wen Chang ),( Jen-her Lu ),( Chin-su Liu ) 대한내과학회 2022 The Korean Journal of Internal Medicine Vol.37 No.4

Background/Aims: Avascular necrosis (AVN) is a clinical condition characterized by the death of bone components due to interruption in the blood supply. This study aimed to investigate the epidemiology and determine the risk factors for AVN in patients with autoimmune diseases. Methods: We conducted a population-based retrospective cohort analysis using claims data from the Taiwan National Health Insurance Research Database. A total of 49,636 patients with autoimmune diseases between January 1, 2005 and December 31, 2013 were included. Cox regression analysis was used to identify associated risk factors for the development of AVN. Results: A total of 490/49,636 patients (1.0%) developed symptomatic AVN. The systemic lupus erythematosus patients had a higher risk of AVN compared to other autoimmune diseases. AVN was positively correlated with male sex (p < 0.001), alcoholism (p < 0.001), mean daily prednisolone dosage 7.51 to 30 mg (p < 0.001) and > 30 mg (p < 0.001), and total cumulative prednisolone dose 0 g to 5 g (p = 0.002). However, AVN was inversely correlated with cumulative duration of hydroxychloroquine exposure > 0.6 years (p < 0.001). Conclusions: Male sex, systemic lupus erythematosus, alcoholism, mean daily corticosteroid > 7.5 mg and a total cumulative dose of corticosteroid 0 to 5 g were independently associated with the development of AVN in autoimmune patients. While hydroxychloroquine use > 0.6 years conferred significant protection against the development of AVN. Clinicians should regularly assess patients with risk factors to enable the early diagnosis of AVN.