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A methodology for assessing attention to and effect of nutrition information displayed front-of-pack is presented. The methodology is based on an integration of the visual search paradigm, the choice paradigm and eye-tracking measures, and moves beyond reliance on self-report measures for attention and choice. Rather the following measures are obtained: (1) respondents’ eye-movements, in terms of dwell time, fixation duration, number of fixations, and saccade size; (2) response times indicating the speed with which choice decisions are made; and (3) consumers’ actual choices from an assortment. The efficiency and sensitivity of the methodology is illustrated in a small scale empirical application. Overall, the methodology seems to be a promising tool for answering puzzling questions in consumer attention and decision making with straightforward potential extensions to enlarge its scope. 相似文献
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Dr. Robert Kuhnert Dr. Lydia Kuhnert Dr. Menyhárt-B. Sárosi Sven George Dr. Dijana Draca Dr. Svetlana Paskas Dr. Bettina Hofmann Prof. Dr. Dieter Steinhilber Prof. Dr. Walther Honscha Prof. Dr. Sanja Mijatović Prof. Dr. Danijela Maksimović-Ivanić Prof. Dr. Evamarie Hey-Hawkins 《ChemMedChem》2022,17(1):e202100588
12-Lipoxygenase is crucial for tumour angiogenesis. 5,6,7-Trihydroxy-2-phenyl-4H-1-benzopyran-4-one (baicalein) is a suitable inhibitor for this enzyme but is rapidly metabolised in vivo. Thus, an improvement of the metabolic stability is necessary to enhance the therapeutic efficiency. An emerging approach to enhance metabolic stability of carbon-based pharmaceuticals is the use of metabolically stable, non-toxic boron clusters, such as dicarba-closo-dodecaborane(12)s (carboranes) as phenyl mimetics. Therefore, the unsubstituted phenyl ring of baicalein was replaced by meta-carborane, resulting in borcalein, the carborane analogue of baicalein. This substitution resulted in a decreased inhibitory activity toward 12-lipoxygenase, but led to increased toxicity in melanoma (A375, B16, B16F10) and colon cancer cell lines (SW480, HCT116, CT26CL25) with decreased tumour selectivity in comparison to baicalein. Surprisingly, borcalein displays a different mechanism of cytotoxicity with increased intracellular production of reactive oxygen species (ROS), reactive nitrogen species (RNS) and nitric oxide (NO). 相似文献
35.
Jiani Wang Jiangtao Li Shamik Dasgupta Li Zhang Mikhail Y. Golovko Svetlana A. Golovko Jiasong Fang 《Lipids》2014,49(4):347-356
Pressure is an important thermodynamic property of the ocean and the deep biosphere that affects microbial physiology and biochemistry. Here, we report on our investigation of the response of Gram-positive piezotolerant bacterium Sporosarcina sp. DSK25 to hydrostatic pressure. Strain DSK25 responded in an adaptive manner to upshifts of growth pressure and showed systematic changes in phospholipid fatty acids. As the pressure increased from 0.1 to 10 MPa (Megapascal), unsaturated fatty acids in DSK25 increased from 21.7 to 31.1 % of total fatty acids, while the level of iso- and anteiso-branched fatty acids remained unchanged. At higher pressures (30, 50, and 60 MPa), the amount of unsaturated fatty acids decreased, and that of anteiso-branched fatty acids increased from 34.4 to 49.9 % at the expense of iso-branched fatty acids. For the first time, two polyunsaturated fatty acids (PUFA), 18:2n-6 and 18:2n-x, with the latter having much higher abundance than the former, were identified in DSK25. The concentration of the PUFA increased with growth pressure. These results indicate the involvement of unsaturated and methyl-branched fatty acids in the modulation of bacteria membrane fluidity and function over environmentally relevant parameter (pressure). Piezotolerant bacterium Sporosarcina sp. DSK25 appears to utilize two regulatory mechanisms for adaptation to high pressure, a rapid-responding mechanism on transient scale, expressed as increased biosynthesis of monounsaturated fatty acids, and a long-term adaptation mechanism in increased synthesis of anteiso-branched and polyunsaturated fatty acids. Our results further suggest that Gram-positive piezophilic bacteria respond differently than Gram-negative bacteria in adaptation to high pressure. 相似文献
36.
Marcel Richter Yuriy Zakrevskyy Michael Eisele Nino Lomadze Svetlana Santer Regine v. Klitzing 《Polymer》2014
The contraction/swelling transition of anionic PNIPAM-co-AAA particles can be manipulated by light using interactions with cationic azobenzene-containing surfactant. In this study the influence of pH-buffers and their concentrations, the charge density (AAA content) in microgel particles as well as the spacer length of the surfactant on the complex formation between the microgel and surfactant is investigated. It is shown that the presence of pH buffer can lead to complete blocking of the interactions in such complexes and the resulting microgel contraction/swelling response. There is a clear competition between the buffer ions and the surfactant molecules interacting with microgel particles. When working in pure water solutions with fixed concentration (charge density) of microgel, the contraction/swelling of the particles is controlled only by relative concentration (charge ratio) of the surfactant and AAA groups of the microgel. Furthermore, the particle contraction is more efficient for shorter spacer length of the surfactant. The onset point of the contraction process is not affected by the surfactant hydrophobicity. This work provides new insight into the interaction between microgel particles and photo-sensitive surfactants, which offers high potential in new sensor systems. 相似文献
37.
While there is good reason to expect crude oil production to be non-linear, previous studies that have examined the stochastic properties of crude oil production have assumed that crude oil production follows a linear process. If crude oil production is a non-linear process, conventional unit root tests, which assume linear and systematic adjustment, could interpret departure from linearity as permanent stochastic disturbances. The objective of this paper is to test for non-linearities and unit roots in crude oil production. To realize our objective, this study applies a threshold autoregressive model with an autoregressive unit root to monthly crude oil production for 17 OPEC and non-OPEC countries over the period January 1973 to December 2007. Specifically, first we test for the presence of non-linearities (threshold effects) in the production of crude oil in two regimes. Second, we test for a unit root against a non-linear stationary process in two regimes and a partial unit root process when the unit root is present in one regime only. We find that crude oil production is characterized by threshold effects. We find that for eleven of the countries a unit root was present in both regimes, while for the others a partial unit root was found to be present in either the first regime or second regime. 相似文献
38.
Plasma Unesterified Fatty‐Acid Profile Is Dramatically and Acutely Changed under Ischemic Stroke in the Mouse Model 下载免费PDF全文
Although plasma biomarkers would facilitate rapid and accurate diagnosis of ischemic stroke for immediate treatment, no such biomarkers have been developed to date. In the present study, we tested our hypothesis that plasma unesterified fatty acids (FFA) are altered at early stages of acute ischemic stroke. Plasma was collected from mice 2 h after the permanent middle cerebral artery occlusion (pMCAo) onset, as well as from sham operated and control animals. After 2 h, pMCAo significantly changed the plasma FFA profile with the most dramatic 2‐ to 3‐fold relative increase in very long n‐3 and n‐6 FFA including 20:4n‐6, 22:4n‐6, 22:5n‐6, and 22:6n‐3. Changes in the plasma FFA profile are consistent with FFA liberation from brain phospholipid hydrolyzed under ischemic insult. These results identify, for the first time, the plasma FFA profile as a potential biomarker for an early ischemic stroke within the therapeutic window for thrombolytic treatment. Further studies are required to confirm its specificity and sensitivity in clinical settings. 相似文献
39.
Nanosized zeolite films for vapor-sensing applications 总被引:2,自引:0,他引:2
Colloidal zeolites LTA and BEA sized below 100 nm were synthesized as building blocks for the controlled growth of thin microporous films on piezoelectric sensor devices (quartz crystal microbalance, QCM). The zeolite films were prepared on pre-seeded gold substrates on QCM devices. Initially, a layer of colloidal particles was deposited on the support through chemical bonding with a silane coupling agent, followed by hydrothermal growth. BEA- and LTA-type zeolite films with thicknesses of 250 and 450 nm, respectively, were prepared by optimizing the synthesis conditions. The application of these zeolite films in microsensors for water and organic compounds is presented. The importance of the zeolite structure type with respect to the sensitivity towards different organic and water vapors at various concentrations is discussed. Both zeolites are thermally stable and show reproducible responses during long-term experiments. Based on these results, it was concluded that both zeolite films could be used effectively as humidity sensor materials for water vapor sensing purposes. High sensitivity, good reversibility and long life were demonstrated for this type of zeolite film at low water concentrations. In comparison to LTA, the BEA films show a higher sorption capacity towards water vapor and no rejection of pentane, hexane and cyclohexane, due to the larger pore size of the BEA structure. 相似文献
40.
Adsorption of methyl mercaptan on activated carbons 总被引:1,自引:0,他引:1
Activated carbons of different origins were studied as methyl mercaptan adsorbents in wet, dry, and oxidizing conditions. The materials were characterized using adsorption of nitrogen, Boehm titration, and thermal analysis. Investigation was focused on the feasibility of the removal of methyl mercaptan on activated carbons and on the role of surface chemistry and porosity in the adsorption/oxidation processes. The results showed relatively high capacities of carbons for removal of CH3SH. The amount adsorbed depends on the surface features. Methyl mercaptan, in general, is oxidized to disulfides, which, depending on the chemistry of the carbon surface, can be converted to sulfonic acid due to the presence of water and active radicals. 相似文献