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Within populations, individual males adopt different courtship tactics due to differences in their competitive ability, which may vary depending on the animal’s age and size. To test the hypothesis that mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) males vary their courtship behavior based on their size, we conducted focal observations of 144 mule deer and 85 white-tailed males that varied in size, at a large grassland site in southern Alberta. The smallest mule deer males devoted more time to feeding, were less likely to engage in late-stage courtship than larger males and were less likely to move among female groups. Other males, including small white-tailed males, appeared to use a roving strategy to search for estrous females in different groups, which is consistent with recent research on male movements. Both medium and large males increased the time they spent in one-male groups, and specifically isolated pairs, as courtship advanced, presumably to reduce competition with other males. However, this trend was most pronounced for medium mule deer males, and for all size classes of white-tailed deer. In contrast, large mule deer males spent a similar proportion of time tending females in all group types. Our results identified potential size-dependent tactics for mule deer males. In contrast, white-tailed males of all sizes appeared to rely on a tactic of finding and tending estrous females in isolation from other males.

Courtship behaviour reflects characteristics of an animal’s general biology, while also reflecting selective pressures specific to reproduction. Mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) are sister species that differ in antipredator behaviour and sociality. We observed sympatric mule deer and white-tailed males to document their grouping patterns, courtship tactics, and aggressive interactions during the breeding season. Consistent with the hypothesis that courtship strategies reflect species differences in antipredator tactics and sociality, mule deer males were more likely than white-tailed males to tend females in multi male–multi female groups. White-tailed males almost exclusively tended females in isolated pairs and prevented other males from joining their groups. However, both species spent more time in isolated pairs as courtship advanced, likely to reduce competition. Our results enabled us to distinguish courtship behaviours that reflect contrasting antipredator tactics and sociality from courtship behaviours that reflect reproductive selective pressures that the species share.

The ATM/HF network architecture is a HF radio broadcast network that utilizes three distinct MAC protocols. ATM/HF integrates into existing communications systems and supports existing and proposed traffic types. The frame and wireless packet structures are based upon a 128 kbps data rate and descriptions of the reference layer model and basic operations show how the network is established and operates. Simulation shows that a single ATM/HF channel can statistically support six voice and ten data users. Use of multiple channels can increase the capacity and range of the network. By using the ATM AAL2 trunking for narrowband services, it is possible to increase the capacity of the current ATM/HF design.

As a tactical user of network services, the US Navy is distinguished by its mobility and its use of low-bandwidth wireless links. ATM technology optimizes bandwidth usage and guarantees QoS for high priority applications. However, wireless and low data rate ATM specifications are just beginning to have commercial availability. This paper discusses the status of emerging ATM specifications that will satisfy US Navy tactical communications requirements.

This paper presents an open systems architecture (OSA) rapid prototyping concept developed at MITRE corporation. The prototype is for a synchronous communications controller. The following OSA elements form the basis of this rapid prototyping concept for real-time systems: VMEbus-based commercial off-the-shelf (COTS) hardware, standardized software, and networking protocol standards. The development methodologies for modeling real-time systems that have been implemented are described in conjunction with the (UNIX/VxWorks host) and target software development environment. By implementing this rapid system prototyping concept, the hardware and software development life cycles are shortened. In addition, the utilization of standards leads to a simplified migration path for upgrading systems. >

International audience; The intersection syndrome, described since the 19th century, is an uncommon disorder associated with the abductor pollicis longus and extensor pollicis brevis bellies (first dorsal compartment) rubbing against the extensor carpi radialis longus and brevis tendons (second dorsal compartment). Overuse occurred in occupational setting was barely described although it could lead to compensation by the French health insurance system. We reported a case of an intersection syndrome in a 58-year-old man who recently became a supermarket cashier. This job involved repeated extension and flexion of the wrist. The disorders arose after a minimal traumatism. Since it is recognized as an occupational disease, compensated ending of the activity causing the disorder could have been obtained.