Plasmid pB15 was previously shown to evolve increased horizontal (infectious) transfer at the expense of reduced vertical (intergenerational) transfer and vice versa, a key trade-off assumed in theories of parasite virulence. Whereas the models predict that susceptible host abundance should determine which mode of transfer is selectively favored, host density failed to mediate the trade-off in ...

Entitled: Transient release of dopamine in response to rewarding stimulation of the medial forebrain bundle and submitted in partial fulfillment of the requirements for the degree of Master of Arts (Psychology) complies with the regulations of the University and meets the accepted standards with respect to originality and quality. _________20___ ______Brian Lewis___________________________ Dean...

Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this tra...

Emotional information is often remembered better than neutral information, but this enhancement can come at the cost of memory for non-emotional stimuli presented alongside emotionally salient items. Two encoding-related factors have been proposed to influence the magnitude of this trade-off: The intensity of the affective response to the scenes (which increases the trade-off) and the cognitive...

Females often select mates on the basis of sexual signals, which can be reliable indicators of male quality when the costliness of these signals prevents cheating. The immunocompetence handicap hypothesis (ICHH) provides a mechanistic explanation of these costs, by proposing a trade-off between immune function and sexual displays. This trade-off arises because testosterone enhances sexual signa...

The objective of this paper is to explore the effect of financial crisis on trade flows of steel industries in the major Asian-Pacific steel producing countries. Using a static and dynamic panel data analysis, we test the hypothesis that the global financial crisis has a negative effect on Asia-Pacific bilateral steel trade flows. We also examine the role of regional trade integration in bilate...

Adult dietary restriction (DR) extends lifespan, but the mechanisms that underlie this effect are not well understood. Many DR studies have demonstrated that lifespan extension tends to be accompanied by a reduction in female fecundity - a correlation widely interpreted as evidence that DR triggers an adaptive re - allocation of resources from reproduction to somatic maintenance. Yet, recent ev...

The paper proposes the use of the Silhouette Coefficient (SC) as a ranking measure to perform instance selection in text classification. Our selection criterion was to keep instances with mid-range SC values while removing the instances with high and low SC values. We evaluated our hypothesis across three well-known datasets and various machine learning algorithms. The results show that our met...

1. Recent reports provide empirical evidence for a negative isometric scaling of (log)leaf number per unit shoot volume (i.e. leafing intensity) to (log)leaf size in woody plants. In this context, a theory of leaf size variation was anticipated, stating that natural selection should have favoured high leafing intensity, given that most tree and shrub species are small-leaved. Leaf size is thus ...