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Systematic Relation (systematic + relation)
Selected AbstractsLay perceptions of ethnic prejudice: causes, solutions, and individual differencesEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2005Gordon Hodson We assessed lay perceptions of the causes of and solutions to ethnic prejudice, and determined whether individual differences related to intergroup relations (social dominance orientation, right-wing authoritarianism) and to cognitive style (personal need for structure, need for cognition) were predictive of these perceptions. Results revealed clear and coherent lay beliefs about the causes of and solutions to ethnic prejudice, and significant relations between perceived causes and solutions. Systematic relations between the intergroup-relevant individual differences and these perceptions also emerged, in ways that may serve to justify and legitimize ethnic bias. Implications for the justification and maintenance of ethnic bias and for intervention programmes are discussed. Copyright © 2005 John Wiley & Sons, Ltd. [source] Is the (E)- , -farnesene only volatile terpenoid in aphids?JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2005F. Francis Abstract:, Herbivore insects use a broad range of chemical cues to locate their host to feed or to oviposit. Whether several plant volatiles are effective allelochemicals for insects, the latter also emit molecules which have infochemical role. The (E)- , -farnesene (EBF) is a well-known aphid alarm pheromone commonly found in all previously tested species. Analysis of the released molecules from 23 aphid species, mainly collected on their natural host plant from May to July, was performed by gas chromatography,mass spectrometry. While EBF was identified as the main volatile substance in 16 species, alone or associated with other molecules, the alarm pheromone was only a minor component of the volatile molecule pattern of five other species. Moreover, two species, Euceraphis punctipennis and Drepanosiphum platanoides, did not release EBF at all but other terpenes were identified. This original observation raised the question on the utility and the source of the non-EBF volatiles. Are these potential infochemical substances produced by the aphid or only absorbed from the host plant? Here we determined that terpenes released by insects were not only provided by the host plants. Indeed, Megoura viciae emitted additional molecules than the ones from several aphid species reared on the same host plant. Moreover, no systematic relation between the feeding behaviour of the aphid species and the volatile releases was observed. Aphid terpene composition and proportion would provide reliable cues to identify the emitting organism, plant or insect. The next step of this work will be to determine the infochemical role of terpenes found in the range of tested aphid samples to better understand the relations between the different tritrophic levels. [source] MONETARY POLICY INDICATORS AS PREDICTORS OF STOCK RETURNSTHE JOURNAL OF FINANCIAL RESEARCH, Issue 4 2008David A. Becher Abstract We explore the linkage between stock return predictability and the monetary sector by examining alternative proxies for monetary policy. Using two complementary methods, we document that failure to condition on the Fed's broad policy stance causes a substantial understatement in the ability of monetary policy measures to predict returns. Industry analyses suggest that cross-industry return differences are also linked to changes in monetary conditions, as monetary policy has the strongest (weakest) relation with returns for cyclical (defensive) industries. Overall, we find that monetary conditions have a prominent and systematic relation with future stock returns, even in the presence of business conditions. [source] Theta rhythm of navigation: Link between path integration and landmark navigation, episodic and semantic memoryHIPPOCAMPUS, Issue 7 2005György Buzsáki Abstract Five key topics have been reverberating in hippocampal-entorhinal cortex (EC) research over the past five decades: episodic and semantic memory, path integration ("dead reckoning") and landmark ("map") navigation, and theta oscillation. We suggest that the systematic relations between single cell discharge and the activity of neuronal ensembles reflected in local field theta oscillations provide a useful insight into the relationship among these terms. In rats trained to run in direction-guided (1-dimensional) tasks, hippocampal cell assemblies discharge sequentially, with different assemblies active on opposite runs, i.e., place cells are unidirectional. Such tasks do not require map representation and are formally identical with learning sequentially occurring items in an episode. Hebbian plasticity, acting within the temporal window of the theta cycle, converts the travel distances into synaptic strengths between the sequentially activated and unidirectionally connected assemblies. In contrast, place representations by hippocampal neurons in 2-dimensional environments are typically omnidirectional, characteristic of a map. Generation of a map requires exploration, essentially a dead reckoning behavior. We suggest that omnidirectional navigation through the same places (junctions) during exploration gives rise to omnidirectional place cells and, consequently, maps free of temporal context. Analogously, multiple crossings of common junction(s) of episodes convert the common junction(s) into context-free or semantic memory. Theta oscillation can hence be conceived as the navigation rhythm through both physical and mnemonic space, facilitating the formation of maps and episodic/semantic memories. © 2005 Wiley-Liss, Inc. [source] | ||||||||||