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排序方式: 共有2183条查询结果,搜索用时 15 毫秒
1.
Shih Yeh Lim Mohd Sokhini Abdul Mutalib Sui Kiat Chang 《International Journal of Food Properties》2018,21(1):2428-2451
There is a growing concern over the food safety issue related to increased incidence of cooking oil adulteration with recycled cooking oil (RCO). The objective of this study was to detect fresh palm olein (FPO) adulteration with RCO using fatty acid composition (FAC) and Fourier-transform infrared spectroscopy (FTIR) spectral analyses combined with chemometrics. RCO prepared in the laboratory was mixed with FPO in the proportion ranged from 1% to 50% (v/v) to obtain the adulterated oil samples (AO). FACs for FPO, RCO, and AO were determined using gas chromatography equipped with a flame ionization detector (GC-FID). The compositions of most fatty acids in RCO lied within the normal ranges of Codex standard, except for C8:0, C10:0, C11:0, C15:0, trans C18:1, and polyunsaturated fatty acids (PUFAs), C20:5. PUFAs showed a consistent decreasing trend with increasing magnitude of change with respect to increasing adulteration level and thus might be a good indicator for detecting FPO adulteration with RCO. The evaluation parameters (coefficient of determination, root mean standard error) of the FTIR-partial least square (PLS) model of palm oil adulteration with recycled oil are R2 = 0.995 and 3.25, respectively. For FTIR spectral analysis, the distinct variations in spectral regions and aberrations in characteristic bands between FPO and RCO were observed. The optimized PLS calibration model developed from normal spectral of the combined region at 3602–3398, 3016–2642, and 1845–650 cm?1 overpredict the adulteration level. On the other hand, the discriminant analysis classification model was able to classify the FPO and AO into two distinct groups. Improvement of the principles of combined techniques in authenticating AO from fresh oil is beneficial as a guideline to detect adulteration in cooking oil. 相似文献
2.
Shengshou Ma Shiyin Ji Changzhong Liao Chengshuai Liu Kaimin Shih Wei He 《Ceramics International》2018,44(13):15124-15132
Zirconolite ceramic has been considered as a promising matrix to dispose high-level radioactive waste due to its excellent performance in immobilizing radionuclides. In this work, a series of zirconate solid solutions with stoichiometric Ca1-xLnxZrTi2-xAlxO7 (Ln = La, Nd, Gd, Ho, Yb; x?=?0.1–1) were systematically studied to investigate the radius effect on their phase evolution. Powder X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-Ray spectrometry (SEM-EDX) were used to characterize the products. XRD and SEM results show that complete solid solutions of Ln and Al in zirconolite phase for Ca1-xLnxZrTi2-xAlxO7 cannot found. In the Ca1-xLaxZrTi2-xAlxO7 ceramics, single zirconolite phase cannot form, instead of multiple phases, such as zirconolite-2M, zirconia, perovskite and LaTi2Al9O19. In the Nd-Al co-doping ceramics, nearly single zirconolite-2M and zirconolite-3O were found at x?≤?0.6 and 0.8?≤?x?≤?0.9, respectively. The miscibility gap between zirconolite-2M and 3O was found at x?=?0.7. Single zirconolite-2M formed in the Gd-Al, Ho-Al and Yb-Al co-doped ceramics can only be detected in a compositional range of 0.1?≤?x?≤?0.8. Higher incorporation contents in these three series can form an additional phase cubic zirconia which is usually a ceramic waste form for radionuclides. Based on the XRD data, lattice parameters of zirconolite-2M and zirconolite-3O were calculated by Pawley refinement method. The evolution of lattice parameters of zirconolite-2M shows great difference between different lanthanide ions, indicating different substitution mechanisms in the Ln-Al co-doped zirconolite-2M. 相似文献
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Tsai Pei-Wei Li Jian-Pan Shih Jia-Shing Chen Yin-Jun Lee Tung-ying Cheng Sheng-Tzong 《Telecommunication Systems》2020,75(2):221-234
Telecommunication Systems - Vehicle-to-vehicle communication and probabilistic broadcast are important means for information dissemination in vehicular ad-hoc networks (VANETs). In contrast to... 相似文献
6.
Neural Computing and Applications - With an increase in online longitudinal users’ interactions, capturing users’ precise preferences and giving accurate recommendations have become an... 相似文献
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Li-Jane Shih Jia-Yu Wang Jing-Yao Jheng An-Ci Siao Yen-Yue Lin Yi-Wei Tsuei Yow-Chii Kuo Chih-Pin Chuu Yung-Hsi Kao 《International journal of molecular sciences》2020,21(23)
Prostate cancer (PCa) is a reproductive system cancer in elderly men. We investigated the effects of betel nut arecoline on the growth of normal and cancerous prostate cells. Normal RWPE-1 prostate epithelial cells, androgen-independent PC-3 PCa cells, and androgen-dependent LNCaP PCa cells were used. Arecoline inhibited their growth in dose- and time-dependent manners. Arecoline caused RWPE-1 and PC-3 cell cycle arrest in the G2/M phase and LNCaP cell arrest in the G0/G1 phase. In RWPE-1 cells, arecoline increased the expression of cyclin-dependent kinase (CDK)-1, p21, and cyclins B1 and D3, decreased the expression of CDK2, and had no effects on CDK4 and cyclin D1 expression. In PC-3 cells, arecoline decreased CDK1, CDK2, CDK4, p21, p27, and cyclin D1 and D3 protein expression and increased cyclin B1 protein expression. In LNCaP cells, arecoline decreased CDK2, CDK4, and cyclin D1 expression; increased p21, p27, and cyclin D3 expression; had no effects on CDK1 and cyclin B1 expression. The antioxidant N-acetylcysteine blocked the arecoline-induced increase in reactive oxygen species production, decreased cell viability, altered the cell cycle, and changed the cell cycle regulatory protein levels. Thus, arecoline oxidant exerts differential effects on the cell cycle through modulations of regulatory proteins. 相似文献
9.
Shao‐Pu Tsai Shih‐Ning Tsai Yu‐Ting Tsai Yu‐Wen Chen Po‐Yen Tung Jer‐Ren Yang Hsueh‐Ren Chen Chih‐Yuan Chen Yuan‐Tsung Wang Ching‐Yuan Huang 《Microscopy research and technique》2019,82(1):4-11
Convergent beam electron diffraction (CBED) in transmission electron microscopy (TEM) was applied to determine local carbon concentrations in low‐carbon transformation‐induced plasticity (TRIP) steels. High‐order Laue‐zone (HOLZ) lines were experimentally obtained for comparison with simulation results. A new procedure for calculating carbon content is thus proposed. Retained austenite (RA) is classified into three types by morphology; the relationship between the carbon content and the corresponding RA morphology is discussed based on CBED results. Furthermore, results of X‐Ray diffractometry measurements are also used for comparison. 相似文献
10.
Eddy Owaga Rong-Hong Hsieh Beatrice Mugendi Sakhile Masuku Chun-Kuang Shih Jung-Su Chang 《International journal of molecular sciences》2015,16(9):20841-20858
Inflammatory bowel diseases (IBD) are characterized by wasting and chronic intestinal inflammation triggered by various cytokine-mediated pathways. In recent years, it was shown that T helper 17 (Th17) cells are involved in the pathogenesis of IBD, which makes them an attractive therapeutic target. Th17 cells preferentially produce interleukin (IL)-17A–F as signature cytokines. The role of the interplay between host genetics and intestinal microbiota in the pathogenesis of IBD was demonstrated. Probiotics are live microorganisms that when orally ingested in adequate amounts, confer a health benefit to the host by modulating the enteric flora or by stimulating the local immune system. Several studies indicated the effectiveness of probiotics in preventing and treating IBD (ulcerative colitis, and Crohn’s disease). Furthermore, there is mounting evidence of probiotics selectively targeting the Th17 lineage in the prevention and management of inflammatory and autoimmune diseases such as IBD. This review highlights critical roles of Th17 cells in the pathogenesis of IBD and the rationale for using probiotics as a novel therapeutic approach for IBD through manipulation of Th17 cells. The potential molecular mechanisms by which probiotics modulate Th17 cells differentiation and production are also discussed. 相似文献