Search results for "selection"
showing 10 items of 1940 documents
Introduction to Expanding Universes : Exploring Games and Transmedial Ways of World-building
2018
Transmedia is a wide concept, as by definition, it is a network of various media forms. It includes also games, both digital and more traditional forms of games. Transmedia productions are often built around a certain television series, but in some cases a digital game has been the core production as well. Games, however, have not been looked at in detail in their role as a part of a transmedia whole. It is important to pay attention to the specificity of games as a media form, to their product-audience relation, and to the way how they incorporate playfulness into that relation. Even in cases where games are just a minor part of the production, the playfulness involved in transmedia user p…
Special interpretation of formal measurement scales for the case of multiple heterogeneous properties
2001
A formal model of measurement is constructed and its components are outlined in this paper. An integrated hierarchical formal four-level structure which allows description of the multiple heterogeneous properties of a complex object under measurement is developed in order to have a uniform tool for the selection of specific scales for the measurement of these properties. A special treatment of a measurement scale defined on the space of the object states is offered, and corresponding structures of basic types of scales are explained permitting to take into consideration distances between relations on these states. Our approach can serve as the uniform formalised basis for development of mea…
Not all bull and bear markets are alike: insights from a five-state hidden semi-Markov model
2022
This paper employs the hidden semi-Markov model and a novel model selection procedure to detect different states in the US stock market. The empirical results suggest that the market is switching between five states that can be classified into three bull states and two bear states. The three bull states are categorized as a low volatility bull market, a high volatility bull market, and a stock market bubble. One of the bear states represents a regular bear market, while the other one corresponds to either a stock market crash or a market correction. The paper demonstrates that the five-state model is consistent with a number of stylized facts and provides many valuable insights into the dyn…
Effect of the host plant on the immunity of a phytophagous insect : influence of grape variety on the ability of the European grapevine moth to defen…
2013
In tritrophic interactions involving phytophagous insects, host plants and natural enemies, trophic levels are highly dependent on each other. Host plant may strongly affect directly phytophagous insect and indirectly natural enemies growing on these phytophagous insects. When a natural enemy attacks a phytophagous insect, the host immune system constitutes the last chance for the host to survive to an infection. A great variation of insect immune system is generally found in populations for susceptibility to pathogens, suggesting that variable selection pressures may have shaped and driven adaptation of immune traits. This project aims to determine the influence of both host plant and natu…
Consumers’ criteria to select food retailers revisited in the current environment.
2022
Food retailing is undergoing major transformations, particularly in France. Hypermarkets are declining, hard-discount stores are gentrifying, e-commerce is mixing with physical distribution, convenience stores are gaining presence and market shares, other forms are emerging: short, collaborative or cooperative channels. Consumers are clearly changing their buying patterns. How do people currently select a form of sale? Are there any changes in their selection criteria or in their perception of food retailing that can explain that they are turning away from hypermarkets to go to more meaningful places? The objective of this research is to revisit the consumers’ criteria to select a form of s…
Male coloration and species recognition in sympatric flycatchers
1994
Currently favoured views for explaining ornaments in males emphasize female preference such that females benefit from increased offspring production, good genes of the offspring, or the attractiveness of sons. Results from long-term studies in the pied flycatcher Ficedula hypoleuca suggest that factors associated with species recognition may also be important for male coloration. In sympatry the collared flycatcher F. albicollis is dominant in competition for nesting sites over the pied flycatcher. Bright pied flycatcher males resemble collared flycatcher males and suffer from interspecific interference, whereas dull and female-like males can acquire nesting sites close to those of the coll…
Interspecific aggression and character displacement in the damselfly Calopteryx splendens
2004
Problems in species recognition are thought to affect the evolution of secondary sexual characters mainly through avoidance of maladaptive hybridization. Another, but much less studied avenue for the evolution of sexual characters due to species recognition problems is through interspecific aggression. In the damselfly, Calopteryx splendens, males have pigmented wing spots as a sexual character. Large-spotted males resemble males of another species, Calopteryx virgo, causing potential problems in species recognition. In this study, we investigate whether there is character displacement in wing spot size and whether interspecific aggression could cause this pattern. We found first that wing …
Overestimation of the strength of size-assortative pairing in taxa with cryptic diversity: a case of Simpson's paradox.
2015
5 pages; International audience; Size-assortative pairing is one of the most common pairing patterns observed in nature and it probably occurs in many taxa with cryptic diversity. Observed patterns of size-assortative pairing in natural populations may thus be influenced by the co-occurrence of noninterbreeding cryptic groups of individuals living in sympatry. To quantify this potential bias, we sampled amphipods from the Gammarus pulex/Gammarus fossarum crustacean species complex in rivers containing two sympatric and morphologically cryptic groups, i.e. molecular operational taxonomic units (MOTUs). Within each river, MOTUs did not interbreed and differed in mean body size. We measured th…
Ecological differentiation and reproductive isolation of two closely related sympatric species of Oenanthe (Apiaceae)
2010
Oenanthe conioides is a lower Elbe endemic plant species growing in the freshwater tidal zone around Hamburg (Germany). Its closest relative Oenanthe aquatica is widely distributed in Eurasia and grows in calm and shallow freshwater. The two species differ in habitat requirements but are otherwise sympatrically distributed, suggesting that ecological divergence has to be maintained in the face of gene flow. In the present study, we investigated ecological differentiation and reproductive isolation in these two species. An amplified fragment length polymorphism analysis found clear genetic differentiation between the two species implying reproductive isolation. A reciprocal transplantation e…
What do we need to know about speciation?
2011
Speciation has been a major focus of evolutionary biology research in recent years, with many important advances. However, some of the traditional organising principles of the subject area no longer provide a satisfactory framework, such as the classification of speciation mechanisms by geographical context into allopatric, parapatric and sympatry classes. Therefore, we have asked where speciation research should be directed in the coming years. Here, we present a distillation of questions about the mechanisms of speciation, the genetic basis of speciation and the relationship between speciation and diversity. Our list of topics is not exhaustive; rather we aim to promote discussion on rese…