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The Policy Consequences of Motivated Information Processing Among the Partisan Elite
An analysis of U.S. budgetary changes shows that, among subaccounts that are cut, Democrats make more large cuts when they control more lawmaking institutions. This surprising finding is consistent with legislators who are subject to motivated reasoning. In an information-rich world, they disproportionately respond to information in line with their bias unless they must make a large accuracy correction. This article tests, for the first time, motivated information processing among legislators. It finds evidence that Democrats engage in motivated information processing and that the effects of it are felt more on social spending and in off-election years
Competency assessment A strategic approach
SIGLEAvailable from British Library Document Supply Centre- DSC:q94/08004 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Comparison of electron paramagnetic resonance methods to determine distances between spin labels on human carbonic anhydrase II.
Four doubly spin-labeled variants of human carbonic anhydrase II and corresponding singly labeled variants were prepared by site-directed spin labeling. The distances between the spin labels were obtained from continuous-wave electron paramagnetic resonance spectra by analysis of the relative intensity of the half-field transition, Fourier deconvolution of line-shape broadening, and computer simulation of line-shape changes. Distances also were determined by four-pulse double electron-electron resonance. For each variant, at least two methods were applicable and reasonable agreement between methods was obtained. Distances ranged from 7 to 24 A. The doubly spin-labeled samples contained some singly labeled protein due to incomplete labeling. The sensitivity of each of the distance determination methods to the non-interacting component was compared
Temporal and Stoichiometric Patterns of Algal Stimulation of Litter-Associated Heterotrophic Microbial Activity
Periphyton communities associated with submerged plant detritus contain interacting autotrophic and heterotrophic microbes, and are sites of extracellular enzymatic activity. The strength and nature of these interactions might be expected to change over time as microbial communities develop on plant litter. Microbial interactions and enzymatic activity can be altered by nutrient availability, suggesting that litter stoichiometry could also affect these phenomena.We grew wetland plants under ambient and nutrientâenriched conditions to generate plant litter of differing nutrient content. In two experiments, we investigated: (1) the influence of algal photosynthesis on fungal and bacterial production and the activities of four extracellular enzymes throughout a 54âday period of microbial colonisation and growth; and (2) the influence of litter stoichiometry on these relationships.Ambient and nutrientâenriched standingâdead plant litter was collected and then submerged in wetland pools to allow for natural microbial colonisation and growth. Litter samples were periodically retrieved and transported to the laboratory for experiments manipulating photosynthesis using the photosystem II inhibitor DCMU (which effectively prevents algal photosynthetic activity). Algal (14Câbicarbonate), bacterial (3Hâleucine), and fungal (14Câacetate) production, and ÎČâglucosidase, ÎČâxylosidase, leucine aminopeptidase, and phosphatase activities (MUFâ or AMCâlabelled fluorogenic substrates) were measured under conditions of active and inhibited algal photosynthesis.Photosynthesis stimulated overall fungal and bacterial production in both experiments, although the strength of stimulation varied amongst sampling dates. Phosphatase activity was stimulated by photosynthesis during the first, but not the second, experiment. No other enzymatic responses to shortâterm photosynthesis manipulations were observed.Microbial communities on highânutrient litter occasionally showed increased extracellular enzyme activity, fungal growth rates, and bacterial production compared to communities on nonâenriched litter, but algal and fungal production were not affected. Litter stoichiometry had no effects on fungal, bacterial, or enzymatic responses to photosynthesis, but the mean enzyme vector analysis angle (a measure of Pâ versus Nâacquiring enzyme activity) was positively correlated to litter N:P, suggesting that elevated litter N:P led to an increase in the relative activity of Pâacquiring enzymes.These results supported the hypothesis that algal photosynthesis strongly influences heterotrophic microbial activity on macrophyte leaf litter, especially that of fungi, throughout microbial community development. However, the strength of this photosynthetic stimulation does not generally depend on small differences in litter nutrient content.Stimulation of microbial heterotrophs by algal photosynthesis could drive diurnal shifts in periphyton community and aquatic ecosystem function, as well as linking green (photoautotrophâbased) and brown (detritalâbased) food webs