Search results for "COD"
showing 10 items of 2985 documents
The complete mitochondrial genome of Bactrocera biguttula (Bezzi) (Diptera: Tephritidae) and phylogenetic relationships with other Dacini
2018
Bactrocera biguttula is an African olive fruit fly that does not attack cultivated olives but rather develops in the fruits of wild species of Olea and Noronhia. The complete mitochondrial genome of an individual specimen was characterized in comparison to other Bactrocera. The phylogenetic relationships of B. biguttula with other Dacini were investigated, with special focus on B. oleae, an agricultural pest known to attack cultivated and wild olives. The sequence had a total length of 15,829 bp, and included the typical features of insect mitogenomes, similarly to the other Bactrocera analysed. Start codons included ATG, ATC, ATT, and TCG (in COI). The majority of stop codons (TAA) were fu…
Platyzoan mitochondrial genomes.
2012
Platyzoa is a putative lophotrochozoan (spiralian) subtaxon within the protostome clade of Metazoa, comprising a range of biologically diverse, mostly small worm-shaped animals. The monophyly of Platyzoa, the relationships between the putative subgroups Platyhelminthes, Gastrotricha and Gnathifera (the latter comprising at least Gnathostomulida, "Rotifera" and Acanthocephala) as well as some aspects of the internal phylogenies of these subgroups are highly debated. Here we review how complete mitochondrial (mt) genome data contribute to these debates. We highlight special features of the mt genomes and discuss problems in mtDNA phylogenies of the clade. Mitochondrial genome data seem to be …
Testing the H.264 error-resilience on wireless ad-hoc networks
2004
The purpose of this paper is to provide a framework to tune and evaluate the performance of the H.264 codec in 802.11b wireless ad-hoc networks. The codec's error-resilience features are measured under stress conditions typical to these networks, and the most critical parameters are presented. We present solutions concerning the random packet loss problem and show how to quickly recover from packet loss bursts.
On the Provisioning of Mobile Digital Terrestrial TV Services to Vehicles With DVB-T
2012
[EN] Most of the DVB-T (Digital Video Broadcasting -Terrestrial) networks deployments worldwide have been designed for fixed rooftop antennas and high transmission capacity, not providing good coverage level for vehicular mobile reception. This letter analyzes how to combine different technical solutions, so far studied individually, in order to increase the robustness of the transmission for vehicular reception to provide in-band mobile services. In particular, we consider: receive antenna diversity, hierarchical modulation, and Application Layer Forward Error Correction (AL-FEC). Performance evaluation results have been obtained by means of simulations, laboratory tests, and field measure…
Mobile radio channel models for present and future wireless communication systems
2008
From the beginnings of mobile communication, there is a high demand for realistic models for mobile fading channels. The reason for the demand is that channel models are essential for the performance evaluation, parameter optimisation, and test of mobile communication systems. Design methods for mobile fading channels are therefore of great importance for system engineers who are involved in the development of present and future mobile communication systems. In this presentation, an overview will be given about several design methodologies commonly used for the design of mobile radio channel models in present and future wireless communication systems. All presented channel models have in co…
BEP analysis of M-ary PSK modulation schemes over double Rice fading channels with EGC
2010
In this article, the performance of M-ary phase shift keying (PSK) modulation schemes over mobile-to-mobile (M2M) fading channels with equal gain combining (EGC) in cooperative networks is analyzed. Narrowband M2M fading channels under line-of-sight (LOS) propagation conditions are modeled as double Rice processes. A dual-hop amplify-and-forward relay network, where LOS components can exist in the transmission links between the source mobile station and the destination mobile station via K mobile relays, is studied. Here, the average bit error probability (BEP) is utilized to evaluate the performance of Mary PSK modulation schemes. A simple analytical approximation for the average BEP of M-…
Learning Pros and Cons of Model-Driven Development in a Practical Teaching Experience
2016
Current teaching guides on Software Engineering degree focus mainly on teaching programming languages from the first courses. Conceptual modeling is a topic that is only taught in last courses, like master courses. At that point, many students do not see the usefulness of conceptual modeling and most of them have difficulty to reach the level of abstraction needed to work with them. In order to make the learning of conceptual modeling more attractive, we have conducted an experience where students compare a traditional development versus a development using conceptual models through a Model-Driven Development (MDD) method. This way, students can check on their own pros and cons of working w…
HEXIM1 Diffusion in the Nucleus Is Regulated by Its Interactions with Both 7SK and P-TEFb
2019
International audience; How nuclear proteins diffuse and find their targets remains a key question in the transcription field. Dynamic proteins in the nucleus are classically subdiffusive and undergo anomalous diffusion, yet the underlying physical mechanisms are still debated. In this study, we explore the contribution of interactions to the generation of anomalous diffusion by the means of fluorescence spectroscopy and simulation. Using interaction-deficient mutants, our study indicates that HEXIM1 interactions with both 7SK RNA and positive transcription elongation factor b are critical for HEXIM1 subdiffusion and thus provides evidence of the effects of protein-RNA interaction on molecu…
Histone deacetylase A key enzyme for the binding of regulatory proteins to chromatin
1993
AbstractCore histones can be modified by reversible, posttranslational acetylation of specific lysine residues within the N-terminal protein domains. The dynamic equilibrium of acetylation is maintained by two enzyme activities, histone acetyltransferase and histone deacetylase. Recent data on histone deacetylases and on anionic motifs in chromatin- or DNA-binding regulatory proteins (e.g. transcription factors, nuclear proto-oncogenes) are summarized and united into a hypothesis which attributes a key function to histone deacetylation for the binding of regulatory proteins to chromatin by a transient, specific local increase of the positive charge in the N-terminal domains of nucleosomal c…
Silicic acid competes for dimethylarsinic acid (DMA) immobilization by the iron hydroxide plaque mineral goethite.
2015
Abstract A surface complexation modeling approach was used to extend the knowledge about processes that affect the availability of dimethylarsinic acid (DMA) in the soil rhizosphere in presence of a strong sorbent, e.g., Fe plaques on rice roots. Published spectroscopic and molecular modeling information suggest for the organoarsenical agent to form bidentate-binuclear inner-sphere surface complexes with Fe hydroxides similar to the inorganic As oxyanions. However, since also the ubiquitous silicic acid oxyanion form the same bidentate binuclear surface complexes, our hypothesis was that it may have an effect on the adsorption of DMA by Fe hydroxides in soil. Our experimental batch equilibr…