PHOTOMORPHOGENESIS IN Penicillium isariaeforme: EXOGENOUS CALCIUM SUBSTITUTES FOR LIGHT

Abstract— Penicillium isariaeforme is a photomorphogenic fungus which produces upright bundles of conidia-bearing mycelia (called coremia) when grown on a defined medium in visible (450–500 nm) light. We found that exogenous Ca²⁺ ions could substitute for light. In the dark 1–2 m M Ca²⁺ triggered coremia formation. Dark induction of coremia was specific for Ca²⁺ in that it could not be duplicated by 50 m M Ba²⁺, Fe²⁺, Mg²⁺, Mn²⁺, Sr²⁺, or Zn²⁺. Additionally, light-induced coremia formation was inhibited by both KI (2.5 m M ) and phenylacetic acid (0.25 m M ).     

THE ORIENTATION OF THE REACTION CENTER CAROTENOID TRIPLET STATE MAGNETIC AXES IN CHROMATOPHORES OF Rhodopseudomonas sphaeroides WILD TYPE

Abstract— The orientation of the principal magnetic axes of the reaction center carotenoid from Rps. sphaeroides wild type is presented. The parameters needed to simulate the observed carotenoid triplet state spectra indicate that the carotenoid adopts a planar structure within the reaction center. A high degree of geometrical and structural specificity is shown to exist for this carotenoid molecule.     

Dissonance Minimization as a Microfoundation of Social Influence in Models of Opinion Formation

Models of opinion formation are used to investigate many collective phenomena. While social influence often constitutes a basic mechanism, its implementation differs between the models. In this article, we provide a general framework of social influence based on dissonance minimization. We only premise that individuals strive to minimize dissonance resulting from different opinions compared to individuals in a given social network. Within a game theoretic context, we show that our concept of dissonance minimization resembles a coordination process when interactions are homogeneous. We further show that different models of opinion formation can be represented as best response dynamics within our framework. Thus, we offer a unifying perspective on these heterogeneous models and link them to rational choice theory.     

OPTIMAL DISCOUNTING IN CONTROL PROBLEMS THAT SPAN MULTIPLE GENERATIONS

ABSTRACT. The principal contribution of this paper is the linking together of separate control problems across multiple generations using the bequest motive, intergenerational altruism, rational expectations, and solution boundary conditions. We demonstrate that discounting at the market rate of interest is an endogenous characteristic of a general equilibrium, optimal control problem that spans multiple generations. Within the confines of our model, we prove that it is optimal to discount at the market rate of interest the social benefits to distant generations from immediate clean up at toxic waste sites if the current generation that bears the cleanup cost is perfectly altruistic towards future generations. Also, we show that this result holds for alternative assumptions regarding pure time preference. Moreover, the result holds regardless of whether selfish interim generations attempt to undo the provisions made for distant generations. In our distortion‐free deterministic model, the evidence for intergenerational discounting at the market rate of interest is compelling.     

RANDOM PENALTIES AND RENEWABLE RESOURCES: A MECHANISM TO REACH OPTIMAL LANDINGS IN FISHERIES

Abstract Recent literature considers illegal landings a moral hazard problem that arises because individual landings are unobservable. The literature proposes incentive schemes to solve the information problem. However, most of the proposed schemes raise huge information requirements and social budget balance is not secured. In this paper, we suggest a random penalty mechanism that reduces the information requirements and secures budget balance in the case of a given number of licensed vessels. In the random penalty mechanism, aggregate landings are measured through stock sizes and the natural growth function. If aggregate landings are below optimal landings, each fisherman receives a subsidy. If aggregate catches are above optimal landings, the mechanism works such that either the fisherman is randomly selected and pays a fine or the fisherman is not selected and receives a subsidy. The fine and subsidy can be designed such that budget balance is secured. Provided risk aversion is sufficiently large and the fine is high enough, the random penalty mechanism will generate optimal individual landings. The budget balance combined with risk aversion drives the result for this advanced tax/subsidy system that does not exhaust the resource rents. The budget balance creates interdependence between fishermen that secure optimality.     

Dominators for Multiple-objective Quasiconvex Maximization Problems

In this paper we address the problem of finding a dominator for a multiple-objective maximization problem with quasiconvex functions. The one-dimensional case is discussed in some detail, showing how a Branch-and-Bound procedure leads to a dominator with certain minimality properties. Then, the well-known result stating that the set of vertices of a polytope S contains an optimal solution for single-objective quasiconvex maximization problems is extended to multiple-objective problems, showing that, under upper-semicontinuity assumptions, the set of (k 21)-dimensional faces is a dominator for k-objective problems. In particular, for biobjective quasiconvex problems on a polytope S, the edges of S constitute a dominator, from which a dominator with minimality properties can be extracted by Branch-and Bound methods.     

Divergence of the stationary Kalman filter for correct and for incorrect noise variances

The convergence properties of the estimation error covariancefor the Kalman filter are analysed. Criteria are derived forconvergence or divergence of the estimation error if the time-invariantKalman filter is used, possibly designed for incorrect noisedata. The analysis uses recently developed convergence resultsfor the solution of the matrix Riccati differential equation.