V. J. Tepedino,∗ ¶ Susan Durham,† Sydney A. Cameron,‡ and Karen Goodell§ ∗Department of Biology, Utah State University, Logan, UT 84322-5305, U.S.A. †Ecology Center, Utah State University, Logan, UT 84322-5205, U.S.A. ‡Department of Entomology and Program in Ecology, Evolution and Conservation (PEEC), University of Illinois, Urbana, IL 61801, U.S.A. §Department of Evolution, Ecology and Organis...

Quantitative changes in groundwater and crises resulting from uncontrolled water extraction have turned water resources management into one of the supply-demand dilemmas in arid regions. The present study evaluated the quantitative situation of water resources in the Ardestan Plain adjoining the Ardestan desert by using the MODFLOW mathematical model. Simulation of groundwater flow in the stead...

In birds with altricial young an important stage in the life history is the age at fledging. In this paper we use an approach proven successful in the prediction of the optimal age at maturity in fish and reptiles to predict the optimal age of fledging in passerines. Integrating the effects of growth on future fecundity and survival leads to the prediction that the optimal age at fledging is gi...

Vigilance decline in narcolepsy has been observed repeatedly in task performance . However, the nature of this vigilance effect is not exactly clear. In order to investigate vigilance problems in narcolepsy, it would be informative to examine to what extent narcolepsy patients differ from healthy people in naturally occurring vigilance fluctuations throughout the day. A general tendency to perf...

Several countries of Asia, including Malaysia, have in recent years experienced spectacular economic growth and social change. This, together with declining fertility rates and mortality rates, and accompanying increased expectation of life at birth have resulted in rapid population ageing of these countries. However, relative to the developed countries, where fertility and mortality declines, ...

1% in 2000. Although the objective was far from being reached (the current rate being close to 2%), in 2000 Mexico had 53 million inhabitants fewer than it would have had if fertility had remained at its 1970 level. The population pyramids of 1930, 1970 and 2000 clearly illustrate this dynamics (Figure 2). In 1930 the population was beginning to recover from the aftereffects of the Revolution a...