Males can gather information on the risk and intensity of sperm competition from their social environment. Recent studies have implicated chemosensory cues, for instance cuticular hydrocarbons (CHCs) in insects, as a key source of this information. Here, using the broad-horned flour beetle (Gnatocerus cornutus), we investigated the importance of contact-derived rival male CHCs in informing male...

There is a growing body of evidence regarding cell competition between normal and mutant mammalian cells, which suggest that it may play a defensive role in the early phase of carcinogenesis. In vitro study in the past has shown that overexpression of vimentin in normal epithelial cells at the contact surface with transformed cells is essential for the cell competition involved in epithelial de...

this study carried out in a factorial layout on completely randomaized block design with three replications, to evaluate the above- and below- ground competition between sesame (sesamum indicum) and pigweed (amaranthus retroflexus), and their impacts on sesame yield and yield component. the experimental treatments were all combination of crop-weed competition (shoot competition, root competitio...

Over the last few years the efficiency of search equilibria has been examined by a number of authors. In a series of papers, Diamond (1981; 1982a; 1982b; 1984) has studied this issue in depth. Diamond (1981) shows that in a market with a distribution of match specific mobility costs, an unemployment insurance programme can improve the ex ante welfare of all workers by inducing each of them to f...

the law of prohibition of unfair competition prohibits any deed or action which is against the normal competition in the market. before emergence of special laws for protection of intellectual property rights, including trademarks, such right could be protected either by tort law claims or law of unfair competition. however, the law of prohibition of unfair competition covers a wider area than ...

This study examined the effects of trade liberalization and exchange rate changes on carbohydrate staples in Nigeria. Secondary data published from 1974 to 2006 on cassava exports and rice imports as well as non-tradable carbohydrate staples were used. It was hypothesized that exchange rate changes and trade liberalization via price relatives, trade intensity and nominal protection coefficient ...

Success in competition for limiting parental resources depends on the interplay between parental decisions over allocation of care and offspring traits. Birth order, individual sex and sex of competing siblings are major candidates as determinants of success in sib-sib competition, but experimental studies focusing on the combined effect of these factors on parent-offspring communication and wi...

Range size variation in closely related species suggests different responses to biotic and abiotic heterogeneity across large geographic regions. Species turnover generates a wide spectrum of species assemblages, resulting in different competition intensities among taxa, creating restrictions as important as environmental constraints. We chose to adopt the widely used phylogenetic relatedness (...

The intensity of competition among forest tree seedlings is poorly understood, but has important ramifications for their recruitment and for the maintenance of species diversity. Intense competition among seedlings could allow competitively dominant species to exclude subordinate species. Alternatively, the low density and small stature of forest tree seedlings could preclude intense interseedl...

the aim of this study was to compare the intensity of pre-competition emotion in athletes with type a and b behavior patterns. out of 108 wrestlers participating in iranian national championships (2005), 32 wrestlers were selected as subjects by global bortner scale. then, 16 subjects with high scores (mean 6.45±0.31) formed type a athletes group and 16 with low scores (mean 3.69 ± 0.47) were c...