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131.
Ilkay Erdogan Orhan Fatma Sezer SenolNilgun Ozturk Galip AkaydinBilge Sener 《Food chemistry》2012,132(3):1360-1367
The ethyl acetate and methanol extracts from 16 Salvia L. species were screened for their inhibitory activity against acetylcholinesterase, butyrylcholinesterase, lipoxygenase, and tyrosinase; the enzymes linked to neurodegeneration. Their antioxidant activity was also tested using DPPH radical scavenging, metal-chelation, and ferric-reducing antioxidant power (FRAP) assays. Total flavonoid content of the extracts was determined by AlCl3 reagent, while HPLC technique was applied for analysis of various phenolic acids in the extracts. The extracts exerted weak cholinesterase and tyrosinase inhibition, and remarkable inhibition against lipoxygenase (13.07 ± 2.73-74.21 ± 5.61%) at 100 μg ml−1. The methanol extracts showed higher antioxidant activity in DPPH radical scavenging and FRAP assays. The extracts were analyzed for their gallic, protocateuchic, p-hydroxy-benzoic, vanillic, caffeic, chlorogenic, syringic, o- and p-coumaric, ferulic, rosmarinic, and tr-cinnamic acid contents and the methanol extract of Salvia ekimiana (153.50 mg 100 g−1) was revealed to be the richest in terms of rosmarinic acid. 相似文献
132.
In order to identify the owner and distributor of digital data, a watermarking scheme in frequency domain for multimedia files is proposed. The scheme satisfies the imperceptibility and persistence requirements and it is robust against additive noise. It consists of a few stages of wavelet decomposition of several subblocks of the original signal using special zero assigned filter banks. By assigning zeros to filters on the high frequency portion of the spectrum, filter banks with frequency selective response are obtained. The information is then inserted in the wavelet-decomposed and compressed signal. Several robustness tests are performed on male voice, female voice, and music files, color and gray level images. The algorithm is tested under white Gaussian noise and against JPEG compression and it is observed to be robust even when exposed to high levels of corruption. 相似文献
133.
Dietary licorice root supplementation reduces diet‐induced weight gain,lipid deposition,and hepatic steatosis in ovariectomized mice without stimulating reproductive tissues and mammary gland
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Zeynep Madak‐Erdogan Ping Gong Yiru Chen Zhao Liwen Xu Kinga U. Wrobel James A. Hartman Michelle Wang Anthony Cam Urszula T. Iwaniec Russell T. Turner Nathan C. Twaddle Daniel R. Doerge Ikhlas A. Khan John A. Katzenellenbogen Benita S. Katzenellenbogen William G. Helferich 《Molecular nutrition & food research》2016,60(2):369-380
134.
Marta Martins Önder Metin Melike Sevim Biljana Šljukić César A.C. Sequeira Tansel Sener Diogo M.F. Santos 《International Journal of Hydrogen Energy》2018,43(23):10686-10697
5 nm palladium nanoparticles (Pd NPs) are synthesized and assembled on reduced graphene oxide-iron oxide nanocomposite (rGO-Fe3O4) to be used in oxygen reduction reaction (ORR) and borohydride oxidation reaction (BOR) studies in alkaline media. The structure and morphology of the resulting Pd/rGO-Fe3O4 hybrid material are evaluated by X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS) analyses. The electrochemical behavior of Pd/rGO-Fe3O4 hybrid material for the ORR and BOR is investigated by voltammetry with rotating disk and rotating ring disk electrode and electrochemical impedance spectroscopy, enabling evaluation of the number of exchanged electrons, Tafel slope, exchange current density and activation energy. The results reveal that ORR at Pd/rGO-Fe3O4 proceeds as a 2-electron process with Tafel slope of 0.133 V dec?1, while BOR proceeds as a 5.6-electron process with Tafel slope of 0.350 V dec?1 and exchange current density of 1.38 mA cm?2. The BOR activation energy was found to be 12.4 kJ mol?1. Overall, this study demonstrates the good efficiency of Pd/rGO-Fe3O4 hybrid material for BOR. 相似文献
135.
Optimization of ultrasound‐assisted extraction of phenolic compounds from grapefruit (Citrus paradisi Macf.) leaves via D‐optimal design and artificial neural network design with categorical and quantitative variables
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136.
The sol–gel transition temperature of skim milk concentrated by microfiltration as affected by pH and protein content
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Johannes Schäfer Ingrid Läufle Christian Schmidt Zeynep Atamer Stefan Nöbel Alina Sonne Reinhard Kohlus Jörg Hinrichs 《International Journal of Dairy Technology》2018,71(3):585-592
This study aimed at determining sol–gel transition temperatures of microfiltered skim milk retentates for different protein levels (6, 8 and 10% (w/w)) and a wide pH range (native pH to 4.6) by means of small‐amplitude oscillatory shear rheology. For a pH of 5.4 to 5.0, the sol–gel transition temperatures decreased significantly with increasing protein content, which did not differ for pH 4.8 and 4.6. The sol–gel transition temperatures of retentates with 10% (w/w) protein at pH 5.4 and 4.6 were 58.4 °C and 10.9 °C, respectively. 相似文献
137.
Zeynep Isik David Arditi Irem Dikmen M. Talat Birgonul 《Canadian Metallurgical Quarterly》2010,26(1):9-18
Globalized competition and customer needs forced construction companies to measure their performance beyond the financial measures such as profitability, turnover, etc. As qualitative determinants were added to measurement systems, their investigation and evaluation became a major area of research. In this study, the impact of “resources and capabilities,” “strategic decisions,” “project management competencies,” and “strength of relationships with other parties” on “company performance” was investigated. A questionnaire survey was administered to 73 Turkish contractors and the results of the survey were analyzed using structural equation modeling. The findings indicate that, as expected, resources and capabilities and strategic decisions have an important and direct impact on company performance, whereas project management competencies and strength of relationships with other parties impact company performance only indirectly, through their impact on companies’ resources and capabilities and strategic decisions. 相似文献
138.
139.
Miscibility conditions and volumetric properties of solutions of poly(dimethylsiloxane) in supercritical carbon dioxide have been determined as a function of polymer molecular weight, polymer concentration, temperature, and pressure. Measurements have been conducted in a variable volume view cell equipped with an LVDT sensor to identify the position of a movable piston and thus the internal volume of the cell and consequently the density of the solution at a given pressure and temperature. The demixing data (in the form of P‐T curves for a given concentration, or as P‐x diagrams at a given T) and the density isotherms are presented for solutions of two polymer samples with different molecular weights (Mw = 38,600; Mw/Mn = 2.84 and Mw = 94,300; Mw/Mn = 3.01) at several concentrations in the range from 0.05 to 10 mass % over a temperature range from 302–425 K. Solution densities corresponding to the demixing points also have been identified. Representation of the demixing densities on the density isotherms, i.e., pressure‐density plots is a new methodology that gives a direct assessment of the volumetric expansion the solution must undergo before phase separation. The temperature–composition diagrams generated at selected pressures show that the poly(dimethylsiloxane) + CO2 solutions display both lower critical solution and upper critical solution type behavior. The lower critical solution temperature moves to lower temperatures and the upper critical solution temperature moves to higher temperatures with decreasing pressure and they eventually merge together at lower pressures forming an hourglass‐shaped region of immiscibility. This behavior is linked to the solvent quality of supercritical carbon dioxide that changes with pressure. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1397–1403, 2000 相似文献
140.
Glioblastoma (GBM) is the most common malignant brain tumor. Despite multimodality treatment with surgical resection, radiation therapy, chemotherapy, and tumor treating fields, recurrence is universal, median observed survival is low at 8 months and 5-year overall survival is poor at 7%. Immunotherapy aims to generate a tumor-specific immune response to selectively eliminate tumor cells. In treatment of GBM, immunotherapy approaches including use of checkpoint inhibitors, chimeric antigen receptor (CAR) T-Cell therapy, vaccine-based approaches, viral vector therapies, and cytokine-based treatment has been studied. While there have been no major breakthroughs to date and broad implementation of immunotherapy for GBM remains elusive, multiple studies are underway. In this review, we discuss immunotherapy approaches to GBM with an emphasis on molecularly informed approaches. 相似文献