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1.
In social environments, decisions not only determine rewards for oneself but also for others. However, individual differences in pro-social behaviors have been typically studied through self-report. We developed a decision-making paradigm in which participants chose from card decks with differing rewards for themselves and charity; some decks gave similar rewards to both, while others gave higher rewards for one or the other. We used a reinforcement-learning model that estimated each participant''s relative weighting of self versus charity reward. As shown both in choices and model parameters, individuals who showed relatively better learning of rewards for charity – compared to themselves – were more likely to engage in pro-social behavior outside of a laboratory setting indicated by self-report. Overall rates of reward learning, however, did not predict individual differences in pro-social tendencies. These results support the idea that biases toward learning about social rewards are associated with one''s altruistic tendencies. 相似文献
2.
Summary Deactivation ofCandida
rugosa lipase was found to be complex. Hydrophobic interaction induced by iso-octane influenced the initial phase of deactivation, and increased the turn-over rate of the intermediate in the transition phase. After urea-treatment the structure of the last phase was not further influenced by thermal treatment, whereas that of initial phase was more sensitive to temperature change. Charge interaction was important in maintaining the structure during the deactivation, and especially anion charge might be a major factor. 相似文献
3.
Separation of yeast proteasome subunits. Immunoreactivity with antibodies against ATP-dependent protease Ti from Escherichia coli 总被引:5,自引:0,他引:5
K Tanaka T Tamura A Kumatori T H Kwak C H Chung A Ichihara 《Biochemical and biophysical research communications》1989,164(3):1253-1261
On two-dimensional gel electrophoresis, proteasomes (multicatalytic proteinase complexes) from the yeast Saccharomyces cerevisiae were separated into a characteristic set of approximately 20 components with molecular weights of 21,000 to 31,000 and isoelectric points of 3.5 to 7.5. The main components were isolated by reverse-phase high performance liquid chromatography on a TSK gel phenyl-5PW RP column and named YC1 to YC11, in order of their elution. Immuno-blot analysis showed that two components (YC1-alpha and YC1-beta) with molecular weights of 30,800 and 28,300 strongly cross-reacted with antibody against the P-component of ATP-dependent protease Ti from Escherichia coli, but no components were found to react with antibodies against the A-component of protease Ti or another ATP-dependent protease La (the Ion gene product) of Escherichia coli. These results indicate a structural relationship between eukaryotic proteasomes and bacterial ATP-dependent protease Ti. 相似文献
4.
5.
Summary A new anionic high molecular weight polysaccharide, Methylan, was produced byMethylobacterium organophilum from methanol as a sole source of carbon and energy under the specific culture conditions. By GPC and light scattering, the molecular weight was determined to be 2–4×106 dalton and the distribution of molecular weight was very homogeneous. Methylan was composed of carbohydrate (80%), uronic acid (12%), protein (6%) and pyruvic acid (5%). The sugar composition of Methylan was identified as glucose, galactose and mannose with the approximate molar ratio of 232. Methylan solution showed a pseudoplastic non-Newtonian fluid property at the concentration above 0.05%. At the concentration of 1% Methylan solution, the consistency index was 18,000 centipoise which was almost 10 times higher than that of Xanthan and the flow behavior index was 0.15. 相似文献
6.
Kyung Hwan Jung Mahn Hoon Park Hong Mo Moon Joon Shick Rhee 《Biotechnology letters》1991,13(12):857-862
Summary In the hepatitis B surface antigen (HBsAg)-producing recombinant yeast culture medium, the supply of Bacto-yeast nitrogen base without amino acids was found to be inadequate due to the lack of the several kinds of vitamins and trace elements. When the culture medium for this recombinant yeast was supplemented with sufficient vitamins and trace elements, its growth, HBsAg production and the stability of plasmid were improved. 相似文献
7.
Identification and characterization of an {alpha}-mannosidase from Trypanosoma cruzi 总被引:1,自引:0,他引:1
Swanson Paul M.; Carter Clint E.; Hager Cindy; Kim Wan Joon; Obermeier Sarah; Oeltmann Thomas N. 《Glycobiology》1992,2(6):563-569
In this report we describe the first purification and characterizationof the acid -mannosidase from the human parasite Trypanosomacruzi. The purified enzyme exhibited a native mol. wt of 240000 Da and is apparently composed of four identical subunitsof mol. wt 58 000 Da. Each of the four subunits contains oneN-linked high-mannose-type oligosaccharide. The -mannosidaseexhibited a pH optimum of 3.5 and a pI of 5.9. This low pH optimumand the ability of swainsonine to inhibit its activity suggestthat the -mannosidase is a lysosomal enzyme. Antibodies againstthe T.cruzi enzyme did not react with mammalian lysosomal -mannosidaseand, conversely, antibody against a rat lysosomal -mannosidasedid not react with the T.cruzi enzyme. Thus, the T.cruzi enzymeappears to be distinct from its mammalian counterpart. -mannosidase lysosomal enzyme Trypanosoma cruzi 相似文献
8.
Summary The effects of time of the day and frequency of application and of purity of artificially deposited pollen loads on fruiting and seed set were studied in Rhinanthus angustifolius (diurnally visited by bumblebees) and Viscaria vulgaris (diurnally visited by bumblebees, nocturnally by sphingid moths).Time of the day did not influence pollination success in either species. Increase of pollination frequency increased fruiting and seed set in Rhinanthus but had no affect on Viscaria. Five successive artificial pollinations were needed to achieve seed set equal to that observed naturally in Rhinanthus while a single artificial pollination was sufficient in Viscaria. Mixing Lupinus and Viscaria pollen did not reduce fruiting and seed set in Viscaria. The results are discussed in relation to observed seed sets in early and late flowers, and small and large patches of Viscaria vulgaris and among Rhinanthus flowers in populations of different densities. 相似文献
9.
Summary The direct, lipase-catalyzed esterifications of glycerol-3-phosphate in an organic solvent system and in a solvent free system were carried out. In a solvent free system only, LPA synthesis could be achieved within the acceptable reaction time. Open reaction system was preferable to closed reaction system for LPA synthesis. Yield of LPA isolated by silica gel column chromatography was 32.3%. 相似文献
10.
Results of Hittorf type transference number measurements are reported for aqueous solutions of lithium, sodium, and potassium dextransulfate (DS) in the concentration range 0.008-0.09 moles of sulfate groups per liter. The results for the polyion transference number are combined with equivalent conductance measurements reported earlier to calculate the polyion equivalent conductance, and the polyion charge fraction based on Wall's method. Our results show that the transference number of this high charge density polyion is larger than unity over the entire concentration range studied, and decreases monotonously with increasing concentration. The calculated charge fraction f of the polyion increases with increasing concentration, and at any concentration/decreases in the order LiDS > NaDS > KDS. A comparison between the conclusions derived from these transport experiments and from both mean and single ion activity measurements in dextransulfate solutions shows the considerable uncertainties involved in either of these methods, and emphasizes the need for the application of a variety of techniques, including spectroscopic techniques, to determine differential ion binding by polyions. 相似文献