195 resultados para Antenna Diversity
Resumo:
In this letter, we propose a simple space-time code to simultaneously achieve both the space and time diversities over time dispersive channels by using two-dimensional lattice constellations and Alamouti codes. The proposed scheme still reserves full space diversity and double-real-symbols joint maximum likelihood decoding which has the similar computation complexity as the Alamouti code.
Resumo:
The ability to switch between propagating modes is important for body-centric applications such as medical body area networks where a single node may need to be able to optimise communications for either on-body sensor links or off-body links to the wider network. Therefore, we present a compact 2.45 GHz active mode-switching wearable antenna for both on-body and off-body wireless communications. The single-layer patch antenna was pattern-switched using shorting pins and had an impedance bandwidth of 253 MHz and 217 MHz for the on-body and off-body radiating modes, respectively. An efficiency of 57 % and 56.8 % was obtained for on-body and off-body mode respectively when placed in close proximity to a phantom that represents a muscle issue at 2.45 GHz.
Resumo:
This study reports the identification of nematode neuropeptide-like protein (nlp) sequelogs from the GenBank expressed sequence tag (EST) database, using BLAST (Basic Local Alignment Search Tool) search methodology. Search strings derived from peptides encoded by the 45 known Caenorhabatitis elegans nlp genes were used to identify more than 1000 ESTs encoding a total of 26 multi-species nlp sequelogs. The remaining 18 nlps (nlp-4, -16, -24 through -36, -39, -41 and -45) were identified only in C elegans, while the sole EST representative of nlp-23 was from Caenorhabditis remanei. Several ESTs encoding putative antibacterial peptides similar to those encoded by the C elegans genes nlp-24-33 were observed in several parasite species. A novel gene (nlp-46) was identified, encoding a single, amidated dodecapeptide (NIA[I/T]GR[G/A]DG[F/L]RPG) in eight species. Secretory signal peptides were identified in at least one species representing each nlp sequelog, confirming that all 46 nematode nlp genes encode secretory peptides. A random sub-set of C elegans NLPs was tested physiologically in Ascaris suum ovijector and body wall muscle bioassays. None of the peptides tested were able to modulate ovijector activity, while only three displayed measurable myoactivity on somatic body wall muscle. AFAAGWNRamide (from nlp-23) and AVNPFLDSIamide (nlp-3) both produced a relaxation of body wall muscle, while AIPFNGGMYamide (nlp-10) induced a transient contraction. Numerical analyses of nip-encoding ESTs demonstrate that nlp-3, -13, -14, -15 and -18 are amongst the most highly represented transcripts in the dataset. Using available bioinformatics resources, this study delineates the nlp complement of phylum Nematoda, providing a rich source of neuropeptide ligands for deorphanisation of nematode neuropeptide receptors. (C) 2008 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
Resumo:
This paper evaluates skills for managing ethno-religious diversity in the context of regeneration, spatial planning and the pursuit of sustainable communities. It draws on experiences in Northern Ireland to explore the type and range of skills required in a society emerging from prolonged conflict and residential segregation. The paper concludes by highlighting the need for a more direct political engagement with agnostic practice that challenges the technical reductionism implied in generic skills frameworks. Here, the implications for practice outside the region are identified.