Based on 750 social interactions, largely at feeding stations, gray squirrels in two woodlots were ranked in a social hierarchy by the percentile rank formula and by the linear method. Correlations of rank in the social hierarchy with age, size of home range, and feeding activity under inclement wind conditions were tested statistically by the Spearman rank correlation coefficient. The social hierarchy of gray squirrels is a "linear right” hierarchy. Males were more dominant than females, and social rank was higher with greater age. The dominant male squirrels were responsible for the majority of the observed sexual contacts with females. Size of home range increased slightly with social rank. Wind was the most important environmental factor restricting feeding activity. Subordinate squirrels in the social hierarchy were not more active than dominant squirrels during inclement wind conditions. Insufficient data were collected to determine a definite relationship of social rank with overwinter mortality and shock losses. / M.S.

The primary object of this research was to develop a two-phase strategy for preventive maintenance and the critical number of units. Maintenance is done if the number of failures is equal to or greater than the critical number of units. The system under consideration had q components. The system failed when k (k < q) components or more failed. This system when subjected to preventive maintenance can be described by a Markov Process. The transition probabilities of the Markov Process were obtained from the distributions qf the strength and stress of the components. The underlying distributions were assumed to be double exponential. Various combinations of the inspection period and the critical number of units were used to obtain the global minimum. The criteria were that the system should not fail and minimum cost. / Master of Science

Random or stochastic integral equations occur frequently in the mathematical description of random phenomena in engineering, physics, biology, and oceanography. The present study is concerned with random or stochastic integral equations of the Volterra type in the form x(t;w) = h(tiW) + fa k(t,T~w)f(T,x(Tjw»dT, t > 0, and of the Fredholm type in the form 00 x(tjw) = h(t:w) + fa ko(t,T;w)e(T,x(T;w»dT, t ~ 0, where w £ Q, the supporting set of a complete probability measure space (n,A,p). A random function x(t:w} is said to be a random solution of an equation such as those above if it satisfies the equation with probability one. It is also required that X(tiW) be a second order stochastic process. The purpose of this dissertation is to investigate the existence, uniqueness, and stochastic stability properties of a random solution of these Volterra and Fredholm stochastic integral equations using the "theory of admissibility" and probabilistic functional analysis. The techniques of successive approximations and stochastic approximation are employed to approximate the random solution of the stochastic Volterra integral equation, and the convergence of the approximations to the unique random solution in mean square and with probability one is proven. Problems in telephone traffic theory, hereditary mechanics, population growth, and stochastic control theory are formulated, and some of the results of the investigation are applied. Finally, a discrete version of the above random integral equations is given, and several theorems concerning the existence, uniqueness, and stochastic stability of a random solution of the discrete equation are proven. Approximation of the random solution of the discrete version is obtained, and its convergence to the random solution is studied. This work extends and generalizes the work done by C. P. Tsokos in Mathematical Systems Theory 3 {1969}, pages 222-231, and M. W. Anderson in his Ph.D. dissertation at the University of Tennessee, 1966, among others. Extensions:of this research to several areas of application are proposed. / Ph. D.

Based on earlier empirical literature for Central and Eastern European Countries this paper attempts to analyze the likely impact of changes in corporate income taxes, in the endowment with production-related material infrastructure and in the institutional environment on Foreign Direct Investment (FDI) - and thus on one channel of regional development in South Eastern European Countries (SEECs). Specifically, we explore the scope for public policy to attract FDI separated by these three policy areas and across the SEECs. Our findings suggest that the potential for SEECs to attract FDI upon changes in these policy areas varies not only substantially between the three policy areas but also within the group of SEECs. Yet, as a general picture, most SEECs have substantial scope to attract FDI by improving their institutional environment as well as their infrastructure endowment. The tax instrument, in contrast, is largely exhausted as a means to attract FDI. Based on these findings some medium- and long-term policy issues are outlined.

L'élimination des cellules apoptotiques est un évènement critique pour le maintien de l'homéostasie tissulaire et pour le contrôle des réponses immunes orchestrées par les phagocytes. A l'heure actuelle, les acteurs et en particulier les signaux « eat-me » impliqués ne sont pas encore entièrement caractérisés. C1q, élément de reconnaissance du complément, participe à la reconnaissance des structures altérées du soi et est un acteur majeur de la tolérance immune. Le travail a porté sur l'identification des signaux exposés au cours de l'apoptose et responsables de la fixation de C1q. Dans un premier temps, l'utilisation de la résonance plasmonique de surface a permis de montrer que C1q se fixe de façon précoce après induction de l'apoptose et que cette reconnaissance implique un composant membranaire. Dans un deuxième temps, différentes approches (biologie cellulaire, biochimie et biologie structurale) ont permis d'identifier la phosphatidylsérine et le désoxyribose de l'ADN comme cibles de C1q à la surface des cellules apoptotiques. Enfin, le rôle respectif au cours de l'apoptose de partenaires connus de C1q (calréticuline et p33) a été précisé. Etant donné la versatilité des propriétés de reconnaissance de C1q, cette molécule aurait donc la capacité originale de détecter et de collecter différents signaux, qui pris ensemble fourniraient un signal fort permettant l'élimination efficace des cellules apoptotiques.

We contribute to the foreign direct investment (FDI) literature by providing first empirical evidence on the relative importance of location fac- tors for service and manufacturing FDI. This is of particular interest as the global stock of inward FDI in the service sector has become predominant in the last ten years. Based on a sectoral panel of eight new European member states in the period of 1998 to 2004 we perform a dynamic panel analysis al- lowing for individual adjustment periods across sectors. Results support our assumption that investment into the service sector, which is characterized by low installation costs, adjusts much faster to its desired level than manufactur- ing FDI. Furthermore, since services are mostly non-tradable, FDI into this sector is largely based on market-seeking motives while manufacturing FDI is also driven by international price competitiveness measured via real unit labor costs. (author´s abstract) / Series: Department of Economics Working Paper Series