The TIGRE gamma-ray telescope

TIGRE is an advanced telescope for gamma-ray astronomy with a few arcmin resolution. From 0.3 to 10 MeV it is a Compton telescope. Above 1 MeV, its multi-layers of double sided silicon strip detectors allow for Compton recoil electron tracking and the unique determination for incident photon direction. From 10 to 100 MeV the tracking feature is utilized for gamma-ray pair event reconstruction. Here we present TIGRE energy resolutions, background simulations and the development of the electronics readout system

In vitro degradation and in vivo biocompatibility of chitosan-poly(butylene succinate) fiber mesh scaffolds

In tissue engineering, the evaluation of the host response to the biomaterial implantation must be assessed to determine the extent of the inflammatory reaction. We studied the degradation of poly(butylene succinate) and chitosan in vitro using lipase and lysozyme enzymes, respectively. The subcutaneous implantation of the scaffolds was performed to assess tissue response. The type of inflammatory cells present in the surrounding tissue, as well as within the scaffold, was determined histologically and by immunohistochemistry. In the presence of lipase or lysozyme, the water uptake of the scaffolds increased. Based on the weight loss data and scanning electron microscopy analysis, the lysozyme combined with lipase had a notable effect on the in vitro degradation of the scaffolds. The in vivo implantation showed a normal inflammatory response, with presence of neutrophils, in a first stage, and macrophages, lymphocytes, and giant cells in a later stage. Vascularization in the surrounding tissue and within the implant increased with time. Moreover, the collagen deposition increased with time inside the implant. In vivo, the scaffolds maintained the structural integrity. The degradation in vitro was faster and greater compared to that observed in vivo within the same time periods.Ana R Costa-Pinto was supported by the scholarship SFRH/24735/2005 from the Portuguese “Fundação para a Ciência e a Tecnologia” (FCT). This work was partially supported by the European Network of Excellence EXPERTISSUES (NMP3-CT-2004-500283) and FCT funded project Maxbone (PTDC/ SAU-ENB/115179/2009)

Twenty Years of Galactic Observations in Searching for Bursts of Collapse Neutrinos with the Baksan Underground Scintillation Telescope

The results of twenty-year-long Galactic observations in neutrino radiation are summarized. Except for the recording of a neutrino signal from the supernova SN 1987A, no Galactic bursts of collapse neutrinos have been detected. An upper bound on the mean frequency of gravitational collapses in our Galaxy was obtained, $f_{collapse} (90$.Comment: latex, 7 pages, 2 eps figure

BG/L Calculations of the QCD Critical Temperature and Equation of State

We summarize the latest results from performing Lattice QCD calculations with two different discretization schemes, asqtad and p4fat3, on the LLNL BG/L supercomputer, and present a plan for continued running to complete the calculation of the QCD transition temperature and equation of state

Intergenerational risk sharing

In this paper we examine government debt and tax-transfer policies that can be improve the allocation of risk between generations. Markets cannot allocate risk efficiently between two generations whenever the two generations are not both alive prior to the occurence of a stochastic event. This implies that government policies transferring risk between generations have the potential to create first-order welfare improvements. Our model provides a non- Keynesian justification for the debt-finance of wars and recessions, as well as an added rationale for Social Security type tax-transfer schemes which aid unlucky generations, e.g. the Depression generation, at the expense of luckier generations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27078/1/0000069.pd

Test beam performance of a CBC3-based mini-module for the Phase-2 CMS Outer Tracker before and after neutron irradiation

The Large Hadron Collider (LHC) at CERN will undergo major upgrades to increase the instantaneous luminosity up to 5–7.5×10$^{34}$ cm$^{-2}$s$^{-1}$. This High Luminosity upgrade of the LHC (HL-LHC) will deliver a total of 3000–4000 fb-1 of proton-proton collisions at a center-of-mass energy of 13–14 TeV. To cope with these challenging environmental conditions, the strip tracker of the CMS experiment will be upgraded using modules with two closely-spaced silicon sensors to provide information to include tracking in the Level-1 trigger selection. This paper describes the performance, in a test beam experiment, of the first prototype module based on the final version of the CMS Binary Chip front-end ASIC before and after the module was irradiated with neutrons. Results demonstrate that the prototype module satisfies the requirements, providing efficient tracking information, after being irradiated with a total fluence comparable to the one expected through the lifetime of the experiment

A constitutive analysis of extensional flow of EVA nanocomposites

Linear and nonlinear oscillatory and extensional flow was studied for polymer layered silicate nanocomposites of organically modified bentonite in ethylene-vinyl acetate copolymer with 18 wt.% of vinyl acetate (EVA18). It was found that the Theological properties of EVA18 nanocomposites were distinctly different from the pure copolymer. The elastic response at low frequencies was significantly enhanced in comparison to that of pure EVA18. The linear to nonlinear transition for stress relaxation measurements and the damping function were examined. The relaxation spectrum was shifted toward the longer relaxation time scales for EVA18 nanocomposites, while the dependence of the damping for EVA18 nanocomposites was much stronger than that of the EVA18. In contrast, the uniaxial extensional viscosity of EVA18 nanocomposites gave weaker strain-hardening properties. The prediction of strain-hardening behaviour for EVA18 and EVA18 nanocomposites through relaxation spectrum and the damping function based on Kaye-Bernstein-Kearsley-Zapas (K-BKZ) model is discussed. A simplified estimation of the nonlinear material parameter ? in the K-BKZ model is proposed to predict more accurately the extensional viscosity for EVA18 and EVA18 nanocomposites. Experimental data and detailed predictions are also presented in this paper