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41.
A method for isolation and quantitation of cellular free fatty acid has been developed. When this method was used to quantitate
the free fatty acid content of various cells and tissues, their levels of free fatty acids were found to vary over a wide
range. In comparing tissue culture cells having different levels of free fatty acid, it was demonstrated that the conditions
of culture and the type of serum in the medium are not responsible for the difference in levels. Isotopic studies have shown
that the cellular free fatty acid is not biosynthesized, but is derived from the free fatty acid of the medium. Preliminary
studies on the fate of the intracellular free fatty acid and a discussion of possible factors controlling the level of this
compound in cells are presented. 相似文献
42.
Barbara Przyjazna 《Polymer》2004,45(8):2559-2566
The series of new dyes, which structures are based on 6H-indolo[2,3-b]quinoxaline skeleton that possess characteristic electronic absorption band at a boundary of UV and visible light were tested as potential light absorbing chromophores for photoinitiated polymerization.The studied dyes can be classified into two different groups. The first is the group, so called ‘the branched dyes’, which structures possess the part of molecule that can rotate without restraints and are characterized by low photoinitiation ability. The second, planar and rigid group of molecules provides another chromophores, which possess quite different properties in comparison to that observed for the branched dyes. Their photoinitiation ability is comparable to that observed for many commercially available photoinitiating systems.The location of electronic absorption spectra at a boundary of UV and visible light makes the tested dyes the good candidates for the photoinitiating system applied in dental restorative materials. Their high molar absorption coefficient allows to decrease the dyes concentration in dental formulation in comparison to commonly used camphorquinone. 相似文献
43.
Thomas M. Odell Chong-Hua Xu Paul W. Schaefer Barbara A. Leonhardt De-Fu Yao Xiang-De Wu 《Journal of chemical ecology》1992,18(12):2153-2159
Pheromone traps baited with (+)-disparlure,cis-7,8-epoxy-2methyocta-decane, captured males ofLymantria dispar, L. monacha, andL. mathura in northeastern People's Republic of China.L. dispar responded to the addition of olefin to (+)-disparlure-baited traps in a negative doseresponse manner. Observations on site and seasonal capture ofL. dispar andL. mathura are discussed.Lepidoptera: Lymantriidae. 相似文献
44.
Garrett BC Dixon DA Camaioni DM Chipman DM Johnson MA Jonah CD Kimmel GA Miller JH Rescigno TN Rossky PJ Xantheas SS Colson SD Laufer AH Ray D Barbara PF Bartels DM Becker KH Bowen KH Bradforth SE Carmichael I Coe JV Corrales LR Cowin JP Dupuis M Eisenthal KB Franz JA Gutowski MS Jordan KD Kay BD Laverne JA Lymar SV Madey TE McCurdy CW Meisel D Mukamel S Nilsson AR Orlando TM Petrik NG Pimblott SM Rustad JR Schenter GK Singer SJ Tokmakoff A Wang LS Wettig C Zwier TS 《Chemical reviews》2005,105(1):355-390
45.
46.
Neural Processing Letters - Albeit automated classifiers offer a standard tool in many application areas, there exists hardly a generic possibility to directly inspect their behavior, which goes... 相似文献
47.
Mariana G. Figueiro Brittany Wood Barbara Plitnick Mark S. Rea 《Journal of the Society for Information Display》2013,21(10):417-421
Self‐luminous electronic devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression. The present paper investigated if light from a 178‐cm (70 in.) television suppressed melatonin. Results showed that light from televisions does not impact melatonin levels in the evening. 相似文献
48.
Susan S. Gray Barbara J. Loud Carole P. Sokolowski 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(2):59-72
Abstract The ability to use and interpret algebraic variables as generalized numbers and changing quantities is fundamental to the learning of calculus. This study considers the use of variables in these advanced ways as a component of algebraic thinking. College introductory calculus students' (n = 174) written responses to algebra problems requiring the use and interpretation of variables as changing quantities were examined for evidence of algebraic and arithmetic thinking. A framework was developed to describe and categorize examples of algebraic, transitional, and arithmetic thinking reflected in these students' uses of variables. The extent to which students' responses showed evidence of algebraic or arithmetic thinking was quantified and related to their course grades. Only one third of the responses of these entering calculus students were identified as representative of algebraic thinking. This study extends previous research by showing that evidence of algebraic thinking in students' work was positively related to successful performance in calculus. 相似文献
49.
50.
Barbara Yersin Jonathan Maïm Fiorenzo Morini Daniel Thalmann 《The Visual computer》2008,24(10):859-870
Real-time crowd motion planning requires fast, realistic methods for path planning as well as obstacle avoidance. In a previous
work (Morini et al. in Cyberworlds International Conference, pp. 144–151, 2007), we introduced a hybrid architecture to handle real-time motion planning of thousands of pedestrians. In this article, we
present an extended version of our architecture, introducing two new features: an improved short-term collision avoidance
algorithm, and simple efficient group behavior for crowds. Our approach allows the use of several motion planning algorithms
of different precision for regions of varied interest. Pedestrian motion continuity is ensured when switching between such
algorithms. To assess our architecture, several performance tests have been conducted, as well as a subjective test demonstrating
the impact of using groups. Our results show that the architecture can plan motion in real time for several thousands of characters.
相似文献
Daniel ThalmannEmail: |