Doctor of Philosophy / Division of Biology / Kristin Michel / The biting midge, Culicoides sonorensis, vectors orbiviruses of economic importance, such as epizootic hemorrhagic disease virus (EHDV). Due to the limitations in available molecular tools, critical Culicoides-orbivirus interactions underlying vector competence remain unclear. To provide a foundation for the study of midge-EHDV interactions, RNA interference (RNAi) was developed as a reverse genetic tool, and EHDV-2 infection dynamics were determined within C. sonorensis. To develop RNAi, exogenous double-stranded RNA (dsRNA) was injected into C. sonorensis adults specific to the C. sonorensis inhibitor of apoptosis protein 1 (CsIAP1) ortholog (dsCsIAP1). A significant decrease in CsIAP1 transcripts was observed in whole midges, with highest reduction in the midgut. In addition, dsCsIAP1-injected midges had increased mortality, a loss of midgut tissue integrity, and increased caspase activity. The longevity and midgut phenotypes were partially reversed by the co-injection of dsRNA specific to the C. sonorensis initiator caspase Dronc ortholog and CsIAP1. These results demonstrated that RNAi can be achieved in the midge midgut through injection of target dsRNAs into the hemolymph. Furthermore, the time course of EHDV-2 infection within C. sonorensis was characterized. EHDV-2 infection was observed in the midgut and secondary tissues, including the salivary glands, by 5 days post-feeding (dpf). These data are consistent with dissemination of EHDV-2 to secondary susceptible tissues throughout the midge via the hemolymph and indicate that virus transmission by C. sonorensis may occur as early as 5 dpf. This work provides a foundation for the future study of Culicoides-orbivirus interactions, including the antiviral role of RNAi at the midgut barrier.

Les zoonoses constituent plus des deux tiers des pathologies virales qui concernent l’homme. Le développement et la démocratisation des outils de métagénomique en font de bons outils d’inventaire et de surveillance de virus potentiellement émergents.Dans un premier temps j’ai développé et validé un protocole expérimental de purification des viromes à ARN qui permettait le maintien de l’infectivité des particules virales. Ce protocole a ensuite été appliqué pour caractériser les communautés virales d’arthropodes hématophages et de prélèvements de faune sauvage. J’ai par la suite réalisé l’inventaire des communautés virales de viande de singe fumée illégalement importée en France et confisquée par les douanes, qui a révélé la présence de nombreux bactériophages, dont certains pourraient infecter des bactéries potentiellement pathogènes pour l’homme.Enfin j’ai caractérisé les communautés virales de culicoïdes collectés au Sénégal, ce qui a permis de mettre en évidence la présence de nombreux virus géants à ADN infectant les amibes. Le séquençage des viromes à ARN a quant à lui révélé la présence d'un certain nombre d'arbovirus qui pourraient constituer un risque d’émergence pour la santé humaine. Du fait de nombreux facteurs intrinsèques et extérieurs à l’agent infectieux, la prédiction des futures émergences de virus zoonotiques est très compliquée voire utopique, mais elle reste un challenge crucial et d’actualité. La stratégie de réalisation d’inventaires des communautés virales présentes dans les différents acteurs des cycles de transmission zoonotique est un premier pas indispensable dans la connaissance des risques potentiels d’émergence en population humaine. / Zoonoses are responsible of more than two thirds of human viral infections. The development of high-throughput sequencing tools and their application in metagenomics allow inventorying the viral communities of various reservoirs in order to detect the emergence of viruses before their infection to humans. In this context, I characterized the viral communities of simian bushmeat illegally imported into France and of Culicoides biting midges, recognized vectors of several viruses of human and veterinary medicine importance. I have first developed a protocol for the purification of RNA viromes which allowed maintaining the infectivity of viral particles. This protocol was subsequently applied to characterize viral communities of bloodsucking arthropods and wildlife samples. In a second part I realized the inventory of viral communities of smoked simian bushmeat illegally imported into France and confiscated by the French customs. This study revealed the presence of a wide diversity of bacteriophages, in which some of them could infect bacteria potentially pathogenic for humans.Finally I characterized the viral communities of Culicoides biting midges collected in Senegal, which revealed the presence of sequences related to several giant DNA viruses infecting amoeba. Sequencing of the RNA virome revealed the presence of several arboviruses that could constitute a risk of emergence of zoonoses for humans.The prediction of future emerging zoonotic viruses is very difficult, if not impossible. However the characterization of viral communities present in the different actors of zoonotic transmission cycle is a first step to evaluate potential risks of transmission to humans.

Military theories regarding surprise has a conceptual way of being described which may influence the effect that surprise actually has on a specific command level. Without sufficient explanations there might be unclear reasons for the conversion of these theories into practice. The existing research shows an increased possibility of surprise within the strategical command level and how to achieve it. It also shows the absence of research regarding what causes surprise on tactical command level, even if some theories describe surprise as being more effective at that level. Special operations can be included within the tactical command level and may offer an explanation. This case study examines which causes may lead to surprise on a tactical command level by analyzing descriptions of special operations within the conduct of regular warfare. With theoretical and empirical references, surprise was achieved in both of the selected cases. The results of the study can be divided in to two categories: the direct and the indirect causes. The categorization gives a further explanation in how to better understand surprise within a specific command level. The study contributes to the existing research by revealing a better understanding for commanders within a tactical command level in how to achieve surprise.

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No / Biting the Bullet prepared a series of briefing papers on key issues for international agreement which fed into the July 2001 UN Conference on the Illicit Trade in Small Arms and Light Weapons in All its Aspects. At this conference, UN member states agreed a Programme of Action which is the primary global framework for tackling the proliferation of SALW. Biting the Bullet is currently engaged in two major areas of activity related to the implementation and further development of the Programme of Action. . Biting the Bullet, in partnership with the International Action Network on Small Arms (IANSA), produced a report monitoring states implementation of the programme of action for the 2003 Biennial Meeting of States (BMS) 'Implementing the Programme of Action 2003, followed by 2005 and 2006.

Culicoides molestus (Skuse) is the major species of biting midge that plagues human comfort in the estuarine Gold Coast region of southeast Queensland. Local authorities have initiated a search for an effective, non-chemical means of control, that would minimize human-midge interaction. The effectiveness of a program to control an organism, such as a biting midge, is dependent upon knowledge of the biology of the particular organism of interest. This project revolved examines the lifecycle of C. molestus in detail. It addresses questions regarding the location, seasonal distribution, and dispersal of its juvenile stages in the sand of infested beaches, and their response to chemical treatment, the monthly and annual cycles of the adult midge, and the possibilities of achieving laboratory oviposition, as a first step to laboratory colonisation. The distribution of eggs, larvae and pupae of C. molestus was found to be mostly concentrated around, but below, mean tide level. They also occurred well below the mean tide level. Eggs and larvae have been recovered from as deep as 10 cm in the sand. A seasonal study of the juveniles of this species indicated that they were more strongly influenced by tides than seasons. After a routine pest-control larviciding treatment, a beach recolonisation study revealed that beaches become suitable for oviposition approximately two months after treatment. Large larvae invaded the sprayed areas within days of treatment, which suggests the existence of a refuge outside of the reach of the insecticide. Larvae found in clean (egg- and larva-free), isolated sand containers, placed on the study beach, indicated that larvae could swim in or on the water as a way of moving around the beach. Extended bite-rate studies highlighted the existence of four peaks in adult midge biting activity during the course of a year, around the mid seasons. The strongest peaks of activity were found to be in autumn and spring, but the data suggest that the species undergoes four generations in a year. Through a series of trial-and-error experiments, oviposition under laboratory conditions was achieved. Although the time from blood-feeding to egg maturation is not yet well determined, it occurs within an eight day mean survival period. Blood quality appears critical for adult blood-fed midge survival. Midges fed on the blood of a volunteer who was frequently exposed to midge bites do not live long enough to mature its eggs. The partial ovarial development of one unfed adult female, reared in the laboratory, indicates that C. molestus is facultatively anautogenous.

There have been proposals of many parity inducing techniques like Forward ErrorCorrection (FEC) which try to cope the problem of channel induced errors to alarge extent if not completely eradicate. The convolutional codes have been widelyidentified to be very efficient among the known channel coding techniques. Theprocess of decoding the convolutionally encoded data stream at the receiving nodecan be quite complex, time consuming and memory inefficient.This thesis outlines the implementation of multistandard soft decision viterbidecoder and word length effects on it. Classic Viterbi algorithm and its variantsoft decision viterbi algorithm, Zero-tail termination and Tail-Biting terminationfor the trellis are discussed. For the final implementation in C language, the "Zero-Tail Termination" approach with soft decision Viterbi decoding is adopted. Thismemory efficient implementation approach is flexible for any code rate and anyconstraint length.The results obtained are compared with MATLAB reference decoder. Simulationresults have been provided which show the performance of the decoderand reveal the interesting trade-off of finite word length with system performance.Such investigation can be very beneficial for the hardware design of communicationsystems. This is of high interest for Viterbi algorithm as convolutional codes havebeen selected in several famous standards like WiMAX, EDGE, IEEE 802.11a,GPRS, WCDMA, GSM, CDMA 2000 and 3GPP-LTE.

In this thesis, fast Viterbi Decoder algorithms for a multi-core system are studied. New parallel Viterbi algorithms for decoding convolutional codes are proposed based on tail biting trellises. The performances of the new algorithms are first evaluated by MATLAB and then Eagle (E-UTRA algorithms for LTE) link level simulations where the optimal parameter settings are obtained based on various simulations. One of the algorithms is proposed for implementation in the product due to its good BLER performance and low implementation complexity. The new parallel algorithm is then implemented on target DSPs for Ericsson internal multi-core system to decode the PUSCH (Physical Uplink Shared Channel) CQI (Channel Quality Indicator) in LTE (Long Term Evolution). And the performance of the new algorithm in the real multi-core system is compared against the current implementation regarding both cycle and memory consumption. As a fast decoder, the proposed parallel Viterbi decoder is computationally efficient which reduces significantly the decoding latency and solves memory limitation problems on DSP.

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