Measuring QoS in an aeronautical opportunistic network architecture with limited access to a satellite communications backhaul

We measure quality of service (QoS) in a wireless network architecture of transoceanic aircraft. A distinguishing characteristic of the network scheme we analyze is that it mixes the concept of Delay Tolerant Networking (DTN) through the exploitation of opportunistic contacts, together with direct satellite access in a limited number of the nodes. We provide a graph sparsification technique for deriving a network model that satisfies the key properties of a real aeronautical opportunistic network while enabling scalable simulation. This reduced model allows us to analyze the impact regarding QoS of introducing Internet-like traffic in the form of outgoing data from passengers. Promoting QoS in DTNs is usually really challenging due to their long delays and scarce resources. The availability of satellite communication links offers a chance to provide an improved degree of service regarding a pure opportunistic approach, and therefore it needs to be properly measured and quantified. Our analysis focuses on several QoS indicators such as delivery time, delivery ratio, and bandwidth allocation fairness. Obtained results show significant improvements in all metric indicators regarding QoS, not usually achievable on the field of DTNs.

Correlation between pre-treatment quasispecies complexity and treatment outcome in chronic HCV genotype 3a

Pre-treatment HCV quasispecies complexity and diversity may predict response to interferon based anti-viral therapy. The objective of this study was to retrospectively (1) examine temporal changes in quasispecies prior to the start of therapy and (2) investigate extensively quasispecies evolution in a group of 10 chronically infected patients with genotype 3a, treated with pegylated alpha 2a-Interferon and ribavirin. The degree of sequence heterogeneity within the hypervariable region 1 was assessed by analyzing 20-30 individual clones in serial serum samples. Genetic parameters, including amino acid Shannon entropy, Hamming distance and genetic distance were calculated for each sample. Treatment outcome was divided into (1) sustained virological responders (SVR) and (2) treatment failure (TF).Our results indicate, (1) quasispecies complexity and diversity are lower in the SVR group, (2) quasispecies vary temporally and (3) genetic heterogeneity at baseline can be used to predict treatment outcome. We discuss the results from the perspective of replicative homeostasis. We discuss the results from the perspective of replicative homeostasis.

Irish dental practitioners perceived barriers to the care of patients with special healthcare needs and the effect of postgraduate training

Inequalities in oral healthcare service provision to people with special health needs have been reported in the Republic of Ireland. These include higher unmet dental treatment needs and longer waiting period to access routine dental treatment than the general population. Aim: The aims of this study were to determine the groups of patients with special needs which pose a challenge to manage in the dental surgery and to examine perceived barriers to the care of these patients. We aimed to determine whether postgraduate training in the management of these patients increases the practitioners’ frequency of treatment and their desire for further training in this area. Methods: A questionnaire was used to survey 326 randomly selected dentists from the Dental Council’s register of dentists. Questionnaire and information sheets explaining the purpose of the survey, confidentiality and anonymity of the responses were posted to the dentists. Results: The results showed that children with intellectual disability posed the biggest challenge for dentists to manage in the dental surgery. Behaviour management issues and the degree of disability were perceived by many dentists as factors that would have high effects on their willingness to treat patients with special needs. Dentists who have postgraduate training in the management of patients with special needs were significantly more willing to treat these patients and to seek additional training in the future. Conclusion: There are links between the training and the willingness of practitioners to undertake dental treatment or patients with special healthcare needs.