Flying ad-hoc network application scenarios and mobility models

[EN] Flying ad-hoc networks are becoming a promising solution for different application scenarios involving unmanned aerial vehicles, like urban surveillance or search and rescue missions. However, such networks present various and very specific communication issues. As a consequence, there are several research studies focused on analyzing their performance via simulation. Correctly modeling mobility is crucial in this context and although many mobility models are already available to reproduce the behavior of mobile nodes in an ad-hoc network, most of these models cannot be used to reliably simulate the motion of unmanned aerial vehicles. In this article, we list the existing mobility models and provide guidance to understand whether they could be actually adopted depending on the specific flying ad-hoc network application scenarios, while discussing their advantages and disadvantages.Bujari, A.; Tavares De Araujo Cesariny Calafate, CM.; Cano, J.; Manzoni, P.; Palazzi, CE.; Ronzani, D. (2017). Flying ad-hoc network application scenarios and mobility models. International Journal of Distributed Sensor Networks. 13(10):1-17. doi:10.1177/1550147717738192S117131

An Accurate Definition of the Status of Inactive Hepatitis B Virus Carrier by a Combination of Biomarkers (FibroTest-ActiTest) and Viral Load

BACKGROUND: The combination of transaminases (ALT), biopsy, HBeAg and viral load have classically defined the inactive status of carriers of chronic hepatitis B. The use of FibroTest (FT) and ActiTest (AT), biomarkers of fibrosis and necroinflammatory activity, has been previously validated as alternatives to biopsy. We compared the 4-year prognostic value of combining FT-AT and viral load for a better definition of the inactive carrier status. METHODS AND FINDINGS: 1,300 consecutive CHB patients who had been prospectively followed since 2001 were pre-included. The main endpoint was the absence of liver-related complications, transplantation or death. We used the manufacturers' definitions of normal FT (< = 0.27), normal AT (< = 0.29) and 3 standard classes for viral load. The adjustment factors were age, sex, HBeAg, ethnic origin, alcohol consumption, HIV-Delta-HCV co-infections and treatment. RESULTS: 1,074 patients with baseline FT-AT and viral load were included: 41 years old, 47% African, 27% Asian, 26% Caucasian. At 4 years follow-up, 50 complications occurred (survival without complications 93.4%), 36 deaths occurred (survival 95.0%), including 27 related to HBV (survival 96.1%). The prognostic value of FT was higher than those of viral load or ALT when compared using area under the ROC curves [0.89 (95%CI 0.84-0.93) vs 0.64 (0.55-0.71) vs 0.53 (0.46-0.60) all P<0.001], survival curves and multivariate Cox model [regression coefficient 5.2 (3.5-6.9; P<0.001) vs 0.53 (0.15-0.92; P = 0.007) vs -0.001 (-0.003-0.000;P = 0.052)] respectively. A new definition of inactive carriers was proposed with an algorithm combining "zero" scores for FT-AT (F0 and A0) and viral load classes. This new algorithm provides a 100% negative predictive value for the prediction of liver related complications or death. Among the 275 patients with the classic definition of inactive carrier, 62 (23%) had fibrosis presumed with FT, and 3 died or had complications at 4 year. CONCLUSION: In patients with chronic hepatitis B, a combination of FibroTest-ActiTest and viral load testing accurately defined the prognosis and the inactive carrier status

Characterization and performance of germanium detectors with sub-keV sensitivities for neutrino and dark matter experiments

Germanium ionization detectors with sensitivities as low as 100 eVee (electron-equivalent energy) open new windows for studies on neutrino and dark matter physics. The relevant physics subjects are summarized. The detectors have to measure physics signals whose amplitude is comparable to that of pedestal electronic noise. To fully exploit this new detector technique, various experimental issues including quenching factors, energy reconstruction and calibration, signal triggering and selection as well as evaluation of their associated efficiencies have to be attended. The efforts and results of a research program to address these challenges are presented.Comment: 18 pages, 18 figures, 3 table; v3 -- Published Versio