Aquatic Stages of Stratiomys normula unilimbata Loew. (Diptera: Stratiomyiidae)

A study of the life cycle and behavior of the Stratiomys normula unilimbata Loew. in a pond in Itasca State Pork, Minnesota, showed that larvae overwinter in the bottom of the shallow pond and emerge in July. Some of the mortality factors are suggested, including the ichneumonid parasite, Ceratophygadeuon sp., reared from the larva and drowning of the pupa following a sudden increase in water level. Drastic reduction of the water level would also result in larval mortality

Human activity modeling and Barabasi's queueing systems

It has been shown by A.-L. Barabasi that the priority based scheduling rules in single stage queuing systems (QS) generates fat tail behavior for the tasks waiting time distributions (WTD). Such fat tails are due to the waiting times of very low priority tasks which stay unserved almost forever as the task priority indices (PI) are "frozen in time" (i.e. a task priority is assigned once for all to each incoming task). Relaxing the "frozen in time" assumption, this paper studies the new dynamic behavior expected when the priority of each incoming tasks is time-dependent (i.e. "aging mechanisms" are allowed). For two class of models, namely 1) a population type model with an age structure and 2) a QS with deadlines assigned to the incoming tasks which is operated under the "earliest-deadline-first" policy, we are able to analytically extract some relevant characteristics of the the tasks waiting time distribution. As the aging mechanism ultimately assign high priority to any long waiting tasks, fat tails in the WTD cannot find their origin in the scheduling rule alone thus showing a fundamental difference between the present and the A.-L. Barabasi's class of models.Comment: 16 pages, 2 figure

Boom, slump, sudden stops, recovery, and policy options. Portugal and the Euro

Over the past 20 years, Portugal has gone through a boom, a slump, a sud- den stop, and now a recovery. Unemployment has decreased, but remains high, and output is still far below potential. Competitiveness has improved, but more is needed to keep the current account in check as the economy recovers. Private and public debt are high, both legacies of the boom, the slump and the sudden stop. Productiv- ity growth remains low. Because of high debt and low growth, the recovery remains fragile. We review the history and the main mechanisms at work. We then review a number of policy options, from fiscal consolidation to fiscal expansion, cleaning up of non-performing loans, labor market reforms, product market reforms, and euro exit. We argue that at this point, the main focus of macroeconomic policy should be twofold. The first is the treatment of non-performing loans, the second is product market reforms and reforms aimed at increasing micro-flexibility in the labor market. Symmetrically, we also argue that at this point, some policies would be undesirable, among them faster fiscal consolidation, measures aimed at decreasing nominal wages and prices, and euro exit.info:eu-repo/semantics/publishedVersio

Off-grid solar milk cooling systems offer technical and market opportunities for remote dairy producers

Irish Ai

Factor demand linkages, technology shocks, and the business cycle

This paper argues that factor demand linkages can be important for the transmission of both sectoral and aggregate shocks. We show this using a panel of highly disaggregated manufacturing sectors together with sectoral structural VARs. When sectoral interactions are explicitly accounted for, a contemporaneous technology shock to all manufacturing sectors implies a positive response in both output and hours at the aggregate level. Otherwise there is a negative correlation, as in much of the existing literature. Furthermore, we find that technology shocks are important drivers of the business cycle