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Wan Su Jung Hanui Ye Mateen Fahad Jun Bae Lee Su Ji Kim Jihui Jang 《Liquid crystals》2016,43(10):1495-1502
In this study, we postulated that the optical retardation magnitude could be used to evaluate the stability of the LC phase through the Mueller matrix polarimeter method in LC emulsion. In addition, we found that the increase of cetearyl alcohol concentration induced the more periodic dense lattice structure in crystalline phase of LC lamellae and the sorbitan olivate was relatively more responsible for higher ordering in LC phase compared to C12–20 alkyl glucoside in terms of molecular parallel packing on the basis of the optical retardation magnitude. Furthermore, it was confirmed that the LC emulsion had higher skin barrier function owing to lower TEWL and higher reflectance than ordinary emulsion on human skin and maintained a uniform phase without phase separation for 8 weeks. 相似文献
224.
Development of simultaneous analysis of tryptophan metabolites in serum and gastric juice – an investigation towards establishing a biomarker test for gastric cancer diagnosis 下载免费PDF全文
Jong Min Choi Won Sang Park Kyo Young Song Hwa Jeong Lee Byung Hwa Jung 《Biomedical chromatography : BMC》2016,30(12):1963-1974
To evaluate changes in tryptophan metabolism and discover diagnostic biomarkers for gastric cancer, a quantitative method was developed for tryptophan and its seven metabolites (indole‐3‐lactic acid, anthranilic acid, serotonin, nicotinic acid, kynurenic acid, kynurenine and 3‐indoxyl sulfate) in both human serum and gastric juice using liquid chromatography–tandem mass spectrometry (LC–MS/MS). Serum and gastric juice were prepared with a simple protein precipitation using aqueous 0.1% formic acid and acetonitrile. As a result, it was found that the kynurenine pathway of tryptophan metabolism was activated in gastric cancer and that the metabolic ratio of kynurenine/tryptophan, which reflects the enzyme activity of indoleamine‐2,3‐dioxygenase, was associated with the observed metabolic changes. Finally, the investigation of tryptophan metabolites, especially kynurenic acid, in serum and gastric juice might serve as biomarkers for gastric cancer. The findings in this study provide critical information of tryptophan metabolism which can be applied to a serum‐based diagnostic test for gastric cancer. 相似文献
225.
Relationships between molecular structure and thermomechanical properties of bio‐based thermosetting polymers 下载免费PDF全文
Jung Ho Yang Arun Srikanth Changwoon Jang Cameron F. Abrams 《Journal of Polymer Science.Polymer Physics》2017,55(3):285-292
Molecular dynamics simulations are used to study highly cross‐linked epoxy networks comprised of furanyl epoxy monomer, 2,5‐bis[(2‐oxiranylmethoxy)methyl]‐furan (BOF), that is cross‐linked by two furanyl amine hardeners, 5,5'‐methylenedifurfurylamine (DFDA) and 5,5'‐ethylidenedifurfirylamine (CH3‐DFDA). Important properties of these fully furan‐based systems, including room temperature density, glass transition temperature, and Young's modulus are found to agree with previous experimental results. We also compare the simulated and experimental values of four fully furan‐based thermosetting materials to those using the conventional resin diglycidyl ether of bisphenol A (DGEBA) cured with the two furanyl hardeners. Our simulation results predict a slight decrease in density and Young's modulus, but no impact on the glass transition temperature, upon adding the methyl group in DFDA. Detailed analyses of the MD trajectories reveal the underlying mechanisms responsible for the observed structure/property relations, which center on the lack of collinear covalent bonds in the BOF molecular structure. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 285–292 相似文献
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In this paper, we show a mathematical construction of Beck–Cohen superstatistics in the Bayesian point of view with the help of the two representations of a gamma function. Furthermore, it is shown how some results for superstatistics are related to each other. 相似文献
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Dr. Anthony J. Kim Dr. Nicholas J. Boylan Dr. Jung Soo Suk Minyoung Hwangbo Tao Yu Benjamin S. Schuster Dr. Liudimila Cebotaru Dr. Wojciech G. Lesniak Joon Seok Oh Pichet Adstamongkonkul Ashley Y. Choi Prof. Dr. Rangaramanujam M. Kannan Prof. Dr. Justin Hanes 《Angewandte Chemie (International ed. in English)》2013,52(14):3985-3988
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Kang-Yeoun Jung Mi-Young Lee Cynthia K. McClure 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Geminal bisphosphonic acids and their salu have long been known to he effective inhibitors of bone resorption and mineralization. which arc common symptoms of diseases such as osteoporosis and Paget's disease [I]. Utilizing penlacovalent nxaphosphoranc chemistry, a variety of acyclic γ-amino mono- and bisphosphonates can be efficiently hynthesizcd. Hydrolysis of the P(V) oxaphospholenes, I and 2. followed by reductive amination [2] of the multing ketones, kds directly to the γ-amino mono and bisphosphonateh 5 and 6. The reaction of secondary amincs with ketones 3 and 4 are slow and low yielding. In reactions with ketones containing a bisphosphonatc. The primary product is the cyclic bisphosphonates. 7. Reactions of primary amines with ketones containing a mono-phosphonate M generally hencr, giving higher yields of the desired prcduct in a rhoncr rcaciion time. Syntheses of compounds, 9–11 were also performed (R1 ? H, R2 ? pentyl, cyclohexyl, benzyl, phenyl) in good yields. 相似文献