Dark Matter Search Perspectives with GAMMA-400

GAMMA-400 is a future high-energy gamma-ray telescope, designed to measure the fluxes of gamma-rays and cosmic-ray electrons + positrons, which can be produced by annihilation or decay of dark matter particles, and to survey the celestial sphere in order to study point and extended sources of gamma-rays, measure energy spectra of Galactic and extragalactic diffuse gamma-ray emission, gamma-ray bursts, and gamma-ray emission from the Sun. GAMMA-400 covers the energy range from 100 MeV to ~3000 GeV. Its angular resolution is ~0.01 deg(Eg > 100 GeV), and the energy resolution ~1% (Eg > 10 GeV). GAMMA-400 is planned to be launched on the Russian space platform Navigator in 2019. The GAMMA-400 perspectives in the search for dark matter in various scenarios are presented in this paperComment: 4 pages, 4 figures, submitted to the Proceedings of the International Cosmic-Ray Conference 2013, Brazil, Rio de Janeir

The Role of Glypicans in Wnt Inhibitory Factor-1 Activity and the Structural Basis of Wif1's Effects on Wnt and Hedgehog Signaling

Proper assignment of cellular fates relies on correct interpretation of Wnt and Hedgehog (Hh) signals. Members of the Wnt Inhibitory Factor-1 (WIF1) family are secreted modulators of these extracellular signaling pathways. Vertebrate WIF1 binds Wnts and inhibits their signaling, but its Drosophila melanogaster ortholog Shifted (Shf) binds Hh and extends the range of Hh activity in the developing D. melanogaster wing. Shf activity is thought to depend on reinforcing interactions between Hh and glypican HSPGs. Using zebrafish embryos and the heterologous system provided by D. melanogaster wing, we report on the contribution of glypican HSPGs to the Wnt-inhibiting activity of zebrafish Wif1 and on the protein domains responsible for the differences in Wif1 and Shf specificity. We show that Wif1 strengthens interactions between Wnt and glypicans, modulating the biphasic action of glypicans towards Wnt inhibition; conversely, glypicans and the glypican-binding “EGF-like” domains of Wif1 are required for Wif1's full Wnt-inhibiting activity. Chimeric constructs between Wif1 and Shf were used to investigate their specificities for Wnt and Hh signaling. Full Wnt inhibition required the “WIF” domain of Wif1, and the HSPG-binding EGF-like domains of either Wif1 or Shf. Full promotion of Hh signaling requires both the EGF-like domains of Shf and the WIF domains of either Wif1 or Shf. That the Wif1 WIF domain can increase the Hh promoting activity of Shf's EGF domains suggests it is capable of interacting with Hh. In fact, full-length Wif1 affected distribution and signaling of Hh in D. melanogaster, albeit weakly, suggesting a possible role for Wif1 as a modulator of vertebrate Hh signaling

Dental status of patients with squamous cell carcinoma of the oropharyngeal region

Purpose of the study. To evaluate changes in the oral cavity in patients with squamous cell carcinoma of the oropharyngeal region after radiation therapy.Materials and methods. The study included 70 patients with oropharyngeal squamous cell carcinoma. All patients underwent external beam radiation therapy. We used dose fractionation mode: 5 fractions per week, single focal dose — 2G. The severity of oral mucositis was assessed using the RTOG evaluation scale.Results. Patients with carcinoma of the oropharyngeal region before the start of the main treatment had pathology of hard tooth tissues (CPU-14.62±1.08), gingival inflammation (PMA-41.71±4.98), periodontal inflammation (CPITN-2.54±0.62). After the end of radiation therapy, oral mucositis was detected in all patients (100%). We found changes in the negative side for all indicators of dental status indices compared to primary CPUs-15.26±0.90; CPITN-3.36±0.58; PMA-49.75±5.28 (p<0.05). Clinical signs of oral mucositis begin to appear as early as 7 days after the start of radiation therapy, RTOG=1,5. After 3 weeks, patients develop severe mucosal lesions with fibrinous plaque and severe pain syndrome (RTOG=3.0), requiring intensive drug therapy (p<0.05).Conclusion. In connection with the early appearance of post-radiation oral mucositis, preventive and therapeutic measures to improve the regeneration

On the Synthesis of Secure Services Composition

International audienceWeb service composition is one of the main research challenges of the last decades. Several frameworks have been developed to compose services in order to meet requirements and constraints imposed by a service consumer. Hereafter, we survey research work on evaluation and automatic synthesis of service composition with a particular eye to security aspects. Furthermore, we describe our logical approach based on the partial model checking technique and open system analysis for the synthesis of secure service orchestrators that are also able to exploit some cryptographic primitives. We also show two implementations able to automatically generate an orchestrator process that composes several services in such a way to guarantee both functional and security requirements