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111.
Cheng Ming-Jen Wu Ming-Der Hsieh Sung-Yuan Chen Chung-Yi Chen Jih-Jung Kuo Yueh-Hsiung 《Chemistry of Natural Compounds》2022,58(3):471-473
Chemistry of Natural Compounds - An icetexane diterpenoid, 9(10→20)-abeo-abietane diterpenoid, annlomultialaskoside (1), has been isolated from the endophytic fungus Annulohypoxylon... 相似文献
112.
Cheng Ming-Jen Wu Ming-Der Kuo Yang-Cheng Chen Jih-Jung Kuo Yueh-Hsiung 《Chemistry of Natural Compounds》2022,58(5):822-824
Chemistry of Natural Compounds - A new furan-2-one, namely monafuranone (1), was isolated from the EtOAc-soluble fraction of a 95% EtOH extract of the red mold rice produced by Monascus. sp.... 相似文献
113.
Huang Chien-Ming Chang Chun-Hao Yang Chang-Syun Lin Chien-Liang Chang Tsung-Hsien Chen Chun-Lin Sung Ping-Jyun Cheng Ming-Jen Cheng Chieh-Yang Chen Jih-Jung 《Chemistry of Natural Compounds》2021,57(6):991-995
Chemistry of Natural Compounds - A new acenaphthylene derivative, salviarisanal (1), has been isolated from the aerial part of Salvia arisanensis, together with six known compounds, carnosol (2),... 相似文献
114.
Cheng Ming-Jen Wu Ming-Der Chen Chung-Yi Hsieh Sung-Yuan Chen Jih-Jung 《Chemistry of Natural Compounds》2021,57(6):1032-1034
Chemistry of Natural Compounds - Investigation of the ethyl acetate-soluble layer from the liquid fermentation of Phialophora lagerbergii, an endophytic fungus isolated from the Taiwanese endemic... 相似文献
115.
Ming-Der Wu Ming-Jen Cheng Jih-Jung Chen Nanthaphong Khamthong Wen-Wei Lin Yueh-Hsiung Kuo 《Molecules (Basel, Switzerland)》2022,27(2)
Seven new compounds, including one dimer novel skeleton, chamaecyformosanin A (1); three diterpenes, chamaecyformosanins B–D (2–4); one sesquiterpene, chamaecyformosanin E (5); and two monoterpenes, chamaecyformosanins F and G (6 and 7) were isolated from the methanol extract of the bark of Chamaecyparis obtusa var. formosana. Their structures were established by the mean of spectroscopic analysis and the comparison of NMR data with those of known analogues. Their structures were elucidated on the basis of physicochemical evidence, in-depth NMR spectroscopic analysis, and high-resolution mass spectrometry. Furthermore, the isolated compounds were subjected to an evaluation of their antimicrobial activity. Metabolites 1, 3, and 4 present antibacterial activities. It is worth mentioning that the chemical composition of the bark of C. obtusa var. formosana has never been studied in the past. This is the first time the barks from C. obtusa var. formosana were studied and two new skeleton compounds, 1 and 7, were obtained. 相似文献
116.
This paper proposes a novel active contour model for image segmentation based on techniques of curve evolution. The paper
introduces an energy functional including a local fuzzy energy and a global fuzzy energy to attract the active contour and
stop it on the object boundaries. The local term allows the method to deal with intensity inhomogeneity in images. The global
term, aside from driving the contour toward the desired objects, is used to avoid unsatisfying results led by unsuitable initial
contour position, a common limitation of models using local information solely. In addition, instead of solving the Euler–Lagrange
equation, the paper directly calculates the alterations of the fuzzy energy. By this way, the contour converges quickly to
the object boundary. Experimental results on both 2D and 3D images validate the effectiveness of the model when working with
intensity inhomogeneous images. 相似文献
117.
Fwu‐Long Mi Shin‐Shing Shyu Sung‐Tao Lee Tsung‐Bi Wong 《Journal of Polymer Science.Polymer Physics》1999,37(14):1551-1564
Chitosan gel beads were prepared using an in‐liquid curing method by the ionotropic crosslinking with sodium tripolyphosphate. Crosslinking characteristics of the chitosan‐TPP beads were improved by the modification of in‐liquid curing mechanism of the beads in TPP solution. Chitosan gel beads cured in pH value lower than 6 were really ionic‐crosslinking controlled, whereas chitosan gel beads cured in pH values higher than 7 were coacervation‐phase inversion controlled accompanied with slightly ionic‐crosslinking dependence. According to the result, significantly increasing the ionic‐crosslinking density of chitosan beads could be achieved by transferring the pH value of the curing agent, TPP, from basic to acidic. The swelling behavior of various chitosan beads in acid appeared to depend on the ionic‐crosslinking density of the chitosan‐TPP beads that were deeply affected by the curing mechanism of the beads. The mechanism of chitosan‐TPP beads swollen in weak acid was chain‐relaxation controlled, while the mechanism of chitosan‐TPP beads swollen in strong acid seem to be not only chain‐relaxation but also chain‐scission controlled. Chitosan‐TPP beads prepared in acidic TPP solution decreased the chain‐scission ability due to the increase of ionic crosslinking density of the beads. By the transition of curing mechanism, the swelling degree of chitosan‐TPP beads was depressed, and the disintegration of chitosan‐TPP beads would not occur in strong acid. The mechanism of ionic‐crosslinking reaction of chitosan beads could be investigated by an unreacted core model, and the curing mechanism of the chitosan beads is mainly diffusion controlled when higher than 5% of chitosan was employed. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1551–1564, 1999 相似文献
118.
Density functional theory, B3LYP/6‐31G** and B3LYP/6‐311+G(2d,p), and ab initio MP2/6‐31G** calculations have been carried out to investigate the conformers, transition states, and energy barriers of the conformational processes of oxalic acid and its anions. QCISD/6‐31G** geometrical optimization is also performed in the stable forms. Its calculated energy differences between the two most stable conformers are very near to the related observed value at 7.0 kJ/mol. It is found that the structures and relative energies of oxalic acid conformers predicted by these methods show similar results, and that the conformer L1 (C2h) with the double‐interfunctional‐groups hydrogen bonds is the most stable conformer. The magnitude of hydrogen bond energies depends on the energy differences of various optimized structures. The hydrogen bond energies will be about 32 kJ/mol for interfunctional groups, 17 kJ/mol for weak interfunctional groups, 24 kJ/mol for intra‐COOH in (COOH)2, and 60 kJ/mol for interfunctional groups in (COOH)COO−1 ion if calculated using the B3LYP/6‐311+G(2d,p) method. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 76: 541–551, 2000 相似文献
119.
Amadeo F. Salvador Chi-Ren Shyu Elizabeth J. Parks 《Experimental & molecular medicine》2022,54(9):1348
Over the past 70 years, the study of lipid metabolism has led to important discoveries in identifying the underlying mechanisms of chronic diseases. Advances in the use of stable isotopes and mass spectrometry in humans have expanded our knowledge of target molecules that contribute to pathologies and lipid metabolic pathways. These advances have been leveraged within two research paths, leading to the ability (1) to quantitate lipid flux to understand the fundamentals of human physiology and pathology and (2) to perform untargeted analyses of human blood and tissues derived from a single timepoint to identify lipidomic patterns that predict disease. This review describes the physiological and analytical parameters that influence these measurements and how these issues will propel the coming together of the two fields of metabolic tracing and lipidomics. The potential of data science to advance these fields is also discussed. Future developments are needed to increase the precision of lipid measurements in human samples, leading to discoveries in how individuals vary in their production, storage, and use of lipids. New techniques are critical to support clinical strategies to prevent disease and to identify mechanisms by which treatments confer health benefits with the overall goal of reducing the burden of human disease.Subject terms: Metabolomics, Translational research, Machine learning 相似文献
120.