Open-pollinated white oak (Quercus alba L.) acorns were collected and stored at 4 °C in November 2004. Three days before sowing in early December, we treated germinating acorns in fi ve ways: no surgery (C); one half of the radicle cut off (HR); whole radicle cut off (WR); one cotyledonary petiole severed (OP); and both cotyledonary petioles severed, which resulted in no embryo axis (NE). Seedl...

The paper gives a collection of open problems on abstract polytopes that were either presented at the Polytopes Day in Calgary or motivated by discussions at the preceding Workshop on Convex and Abstract Polytopes at the Banff International Research Station in May 2006.

We studied the effect of nearest pattern interaction on a global pattern formation in a two-dimensional space, where patterns are to grow initially from a noise in the presence of a periodic supply of energy. Although our approach is general, we found that this study is relevant in particular to the pattern formation on a periodically vibrated granular layer, as it gives a unified perspective o...

During the Mars Society's Mars Desert Research Station (MDRS) Rotation 49 (April 23May 7, 2006), we field tested and significantly extended a prototype monitoring and advising system for the habitat crew that integrates data from the MDRS power system. A distributed, wireless network of functionally specialized agents interact with the crew to provide alerts, access and interpret historical dat...

To mitigate the effects of a corrosive operating environment, the Coast Guard has planned an extensive preventative maintenance program for its Sikorsky HH60J helicopters based on helicopter flight time. We construct a mixed integer linear program that schedules the weeks during which each helicopter undergoes maintenance, as well as the weeks during which a helicopter conducts operations eithe...

The ability of Gaussian noise to induce ordered states in dynamical systems is here presented in an overview of the main stochastic mechanisms able to generate spatial patterns. These mechanisms involve: (i) a deterministic local dynamics term, accounting for the local rate of variation of the field variable, (ii) a noise component (additive or multiplicative) accounting for the unavoidable env...

this experiment was conducted to determine the effect of competition between common weed in chickpea’s form in kermanshah and chickpea (cicer arietinum). it was carried out in sararood experimental station in kermanshah province in 2000. split plot factorial was considered as an experimental design that had four replications. the weeding was main factor with two different levels (whole season w...

A feeding station is the area of forage a grazing animal can reach without moving its forefeet. Grazing behavior can be divided into residence within feeding stations (with bites as benefits) and movement between feeding stations (with steps as costs). However, relatively little information has been reported on how grazing animals modify their feeding station behavior seasonally and interannual...

Localized ecological interactions can generate striking large-scale spatial patterns in ecosystems through spatial self-organization. Possible mechanisms include oscillating consumer-resource interactions, localized disturbance-recovery processes and scale-dependent feedback. Despite abundant theoretical literature, studies revealing spatial self-organization in real ecosystems are limited. Rec...