Preprojective representations of valued quivers and reduced words in the Weyl group of a Kac-Moody algebra

This paper studies connections between the preprojective representations of a valued quiver, the (+)-admissible sequences of vertices, and the Weyl group by associating to each preprojective representation a canonical (+)-admissible sequence. A (+)-admissible sequence is the canonical sequence of some preprojective representation if and only if the product of simple reflections associated to the vertices of the sequence is a reduced word in the Weyl group. As a consequence, for any Coxeter element of the Weyl group associated to an indecomposable symmetrizable generalized Cartan matrix, the group is infinite if and only if the powers of the element are reduced words. The latter strengthens known results of Howlett, Fomin-Zelevinsky, and the authors

The Impact of Stereotype Threat on the Academic Performance of International Students Studying in the United States

Stereotype threat can be experienced by anyone who belongs to a group whose status is made relevant by situational features. This study examined the impact of stereotype threat on international students studying in the United States. It was hypothesized that international students reminded that they will underperform on an outcome measure will do just that as compared to international students not so reminded. Thirty-six international students from a small northwest private university participated in the study. Participants were divided into control and experiment groups. Results indicated no significant differences in performance between the two groups. The results of this study are discussed within the framework of stereotype threat and suggest further studies regarding international students and this phenomenon

The influence of temperature and body size on food consumption in prairie lizards (Sceloporus consobrinus)

Understanding the effect of temperature on physiological and digestive processes, such as voluntary consumption rate, is critical for assessing the impact of climate change. Food consumption is required for lizard survival and reproduction and its rate is dependent on temperature. For ectotherms, as temperatures increase, the amount of food consumed to meet the energy requirements related to survival and reproduction must also increase. Information on the amount of food voluntarily consumed may aid in determining if lizards can meet energy requirements. Such information could also aid in predicting survival of lizard populations, through construction of predictive climate change models. In this study, I investigated the effect of body temperature on voluntary consumption for the prairie lizard, Sceloporus consobrinus. I also determined the effects of body mass, body size (snout-vent length), and total length (TL) on consumption rates. In the laboratory, I conducted feeding trials over a range of temperatures (23.0°C, 28.0°C, 30.0°C, 33.0°C, and 36.0°C) and body sizes measuring the amount of food consumed by each individual lizard. I found that consumption per lizard was highly dependent on temperature, and that between body temperatures 23.0°C - 36.0°C, consumption increased with subsequent increases in temperature. No relationship was found between body mass, body size (SVL), or total length (TL) on consumption rate. I concluded that body temperature significantly influences voluntary consumption rates of Sceloporus consobrinus. Through effects on body temperature, climate change will influence critical physiological functions such as feeding rates. These effects have important implications for growth, reproduction and survival of lizard populations in novel climates

Analysis of occupational information content in selected home economics text books

Thesis (Ed.M.)--Boston Universit

Perceptions of randomness in binary sequences: Normative, heuristic, or both?

When people consider a series of random binary events, such as tossing an unbiased coin and recording the sequence of heads (H) and tails (T), they tend to erroneously rate sequences with less internal structure or order (such as HTTHT) as more probable than sequences containing more structure or order (such as HHHHH). This is traditionally explained as a local representativeness effect: Participants assume that the properties of long sequences of random outcomes—such as an equal proportion of heads and tails, and little internal structure—should also apply to short sequences. However, recent theoretical work has noted that the probability of a particular sequence of say, heads and tails of length n, occurring within a larger (>n) sequence of coin flips actually differs by sequence, so P(HHHHH) < P(HTTHT). In this alternative account, people apply rational norms based on limited experience. We test these accounts. Participants in Experiment 1 rated the likelihood of occurrence for all possible strings of 4, 5, and 6 observations in a sequence of coin flips. Judgments were better explained by representativeness in alternation rate, relative proportion of heads and tails, and sequence complexity, than by objective probabilities. Experiments 2 and 3 gave similar results using incentivized binary choice procedures. Overall the evidence suggests that participants are not sensitive to variation in objective probabilities of a sub-sequence occurring; they appear to use heuristics based on several distinct forms of representativeness