The experience of experts relies on the process of decision-making jointly with the progressive elaboration of a context-specific model. However, context modeling generally stays implicit because only the result of the decisionmaking process matters. Modeling context within a decision-making process supposes a uniform representation of knowledge, reasoning and contexts. In the Contextual-Graphs...

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Concern has been voiced about the survival of endangered species, and even the long-term prospects for humans, in the face of accumulating deleterious mutations. Two experiments have investigated the mutation accumulation process in laboratory Drosophila populations, with apparently conflicting results.

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In the first 25 generations of his classical mutation accumulation experiment, T. Mukai estimated a large rate of early linear decay for the relative viability of Drosophila melanogaster chromosome II (delta MII = 0.004). Mukai forced through zero the regression of viability decline on generation number, but it has recently been shown (Fry, 2001) that a similar decline (delta MII = 0.006) is ob...

This paper analyses the correlation between employment duration, unemployment duration and general skill accumulation in a search equilibrium. I show how the level of general skills and the duration of employment are positively correlated, and both variables are negatively correlated with the duration of unemployment spells. With search frictions, general skill accumulation is associated with a...

background: due to the presence of radioactive minerals such as monazite, the beach sand of the west coast of kanyakumari exhibits high natural background radiation. hair is a good indicator of radionuclides in the human body. an attempt is taken to measure the 210po activity in human hair samples and the factors affecting it. material and methods: 210po activity was analysed in 47 individuals ...