116 research outputs found

    Differences in Emergence Date and Size Between the Sexes of \u3ci\u3eMalacosoma Americanum\u3c/i\u3e the Eastern Tent Caterpillar (Lepidoptera: Lasiocampidae)

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    Malacosoma americanum males were smaller and began to pupate earlier than females. Since the sexes spent the same amount of time as pupae, males also emerged earlier. The adaptive significance of these results is discussed. Emergence data revealed an interesting sidelight; no moths emerged from cocoons inside tents

    A framework for the simulation of structural software evolution

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    This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2008 ACM.As functionality is added to an aging piece of software, its original design and structure will tend to erode. This can lead to high coupling, low cohesion and other undesirable effects associated with spaghetti architectures. The underlying forces that cause such degradation have been the subject of much research. However, progress in this field is slow, as its complexity makes it difficult to isolate the causal flows leading to these effects. This is further complicated by the difficulty of generating enough empirical data, in sufficient quantity, and attributing such data to specific points in the causal chain. This article describes a framework for simulating the structural evolution of software. A complete simulation model is built by incrementally adding modules to the framework, each of which contributes an individual evolutionary effect. These effects are then combined to form a multifaceted simulation that evolves a fictitious code base in a manner approximating real-world behavior. We describe the underlying principles and structures of our framework from a theoretical and user perspective; a validation of a simple set of evolutionary parameters is then provided and three empirical software studies generated from open-source software (OSS) are used to support claims and generated results. The research illustrates how simulation can be used to investigate a complex and under-researched area of the development cycle. It also shows the value of incorporating certain human traits into a simulation—factors that, in real-world system development, can significantly influence evolutionary structures

    Differences in Emergence Date and Size Between the Sexes of \u3ci\u3eMalacosoma Americanum\u3c/i\u3e the Eastern Tent Caterpillar (Lepidoptera: Lasiocampidae)

    Get PDF
    Malacosoma americanum males were smaller and began to pupate earlier than females. Since the sexes spent the same amount of time as pupae, males also emerged earlier. The adaptive significance of these results is discussed. Emergence data revealed an interesting sidelight; no moths emerged from cocoons inside tents

    Effects of thermal fluctuation and the receptor-receptor interaction in bacterial chemotactic signalling and adaptation

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    Bacterial chemotaxis is controlled by the conformational changes of the receptors, in response to the change of the ambient chemical concentration. In a statistical mechanical approach, the signalling due to the conformational changes is a thermodynamic average quantity, dependent on the temperature and the total energy of the system, including both ligand-receptor interaction and receptor-receptor interaction. This physical theory suggests to biology a new understanding of cooperation in ligand binding and receptor signalling problems. How much experimental support of this approach can be obtained from the currently available data? What are the parameter values? What is the practical information for experiments? Here we make comparisons between the theory and recent experimental results. Although currently comparisons can only be semi-quantitative or qualitative, consistency is clearly shown. The theory also helps to sort a variety of data.Comment: 26 pages, revtex. Journal version. Analysis on another set of data on adaptation time is adde

    Biometfical genetic analysis of serum Cholesterol response and basal serum HDL cholesterol level in the rabbit

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    The inheritance of the susceptibility for dietary cholesterol (serum cholesterol response) and of basal serum HDL cholesterol level in the rabbit have been studied by measuring serum total cholesterol levels and HDL cholesterol levels in animalsfrom crosses between hyperresponding and hyporesponding inbred strains. The serum cholesterol response and basal serum HDL cholesterol levels of the resulting six populations (the two parental strains, Fl-hybrid, two baekerosses and F7)were subjected to a biomedical genetic analysis to determine the number of loci involved and the (narrow sense) heritability 0f the two traits. The study revealed that 30% of the individual variation of the serum cholesterol response is under geneticcontrol and that 10 to 16 loci may be involved. The heritability for basal serum HDL cholesterol levels was 50 to 80%, whereas two to five loci may be involved in regulating the basal serum HDL cholesterol level in rabbits

    Rabbit serum esterase genotyping and relationship to serum cholesterol response and basal serum HDL cholesterol level

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    Previous studies have indicated that esterases might be involved in the serum cholesterol response in rabbits. The question addressed in this study is whether in rabbits esterase loci of Linkage Group VI (LG VI) are genetically linked withthe serum cholesterol response to dietary cholesterol or the basal serum HDL cholesterol level. For this purpose the Est-2 and Es-1 genotypes of rabbits in segregating populations derived from a cross between IIIVO/JU (hyporespender andhigh basal serum HDL cholesterol level) and AX/1U (hypettesponder and low basal serum HDL cholesterol level) rabbits were determined. The segregating populations were fed a cholesterol-rich diet for 35 days. Both the Est-2 and Es—1 alleles failed to cosegregate with the serum cholesterol response, whereas a highly significant cosegregation was found with the basal serum HDL cholesterol level. It is concluded that one or more genes of LG VI are regulating the basal serumHDL cholesterol level in rabbits
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