The digital data processing concepts of the LOFT mission

The Large Observatory for X-ray Timing (LOFT) is one of the five mission candidates that were considered by ESA for an M3 mission (with a launch opportunity in 2022 - 2024). LOFT features two instruments: the Large Area Detector (LAD) and the Wide Field Monitor (WFM). The LAD is a 10 m 2 -class instrument with approximately 15 times the collecting area of the largest timing mission so far (RXTE) for the first time combined with CCD-class spectral resolution. The WFM will continuously monitor the sky and recognise changes in source states, detect transient and bursting phenomena and will allow the mission to respond to this. Observing the brightest X-ray sources with the effective area of the LAD leads to enormous data rates that need to be processed on several levels, filtered and compressed in real-time already on board. The WFM data processing on the other hand puts rather low constraints on the data rate but requires algorithms to find the photon interaction location on the detector and then to deconvolve the detector image in order to obtain the sky coordinates of observed transient sources. In the following, we want to give an overview of the data handling concepts that were developed during the study phase.Comment: Proc. SPIE 9144, Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray, 91446

Hyper-velocity impact test and simulation of a double-wall shield concept for the Wide Field Monitor aboard LOFT

The space mission LOFT (Large Observatory For X-ray Timing) was selected in 2011 by ESA as one of the candidates for the M3 launch opportunity. LOFT is equipped with two instruments, the Large Area Detector (LAD) and the Wide Field Monitor (WFM), based on Silicon Drift Detectors (SDDs). In orbit, they would be exposed to hyper-velocity impacts by environmental dust particles, which might alter the surface properties of the SDDs. In order to assess the risk posed by these events, we performed simulations in ESABASE2 and laboratory tests. Tests on SDD prototypes aimed at verifying to what extent the structural damages produced by impacts affect the SDD functionality have been performed at the Van de Graaff dust accelerator at the Max Planck Institute for Nuclear Physics (MPIK) in Heidelberg. For the WFM, where we expect a rate of risky impacts notably higher than for the LAD, we designed, simulated and successfully tested at the plasma accelerator at the Technical University in Munich (TUM) a double-wall shielding configuration based on thin foils of Kapton and Polypropylene. In this paper we summarize all the assessment, focussing on the experimental test campaign at TUM.Comment: Proc. SPIE 9144, Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray, 91446

FlashCam: A fully digital camera for CTA telescopes

The future Cherenkov Telescope Array (CTA) will consist of several tens of telescopes of different mirror sizes. CTA will provide next generation sensitivity to very high energy photons from few tens of GeV to >100 TeV. Several focal plane instrumentation options are currently being evaluated inside the CTA consortium. In this paper, the current status of the FlashCam prototyping project is described. FlashCam is based on a fully digital camera readout concept and features a clean separation between photon detector plane and signal digitization/triggering electronics.Comment: In Proceedings of the 2012 Heidelberg Symposium on High Energy Gamma-Ray Astronomy. All CTA contributions at arXiv:1211.184

Proteome-wide characterization of the RNA-binding protein RALY-interactome using the in vivo-biotinylation-pulldown-quant (iBioPQ) approach

RALY is a member of the heterogeneous nuclear ribonucleoproteins, a family of RNA-binding proteins generally involved in many processes of mRNA metabolism. No quantitative proteomic analysis of RALY-containing ribonucleoparticles (RNPs) has been performed so far, and the biological role of RALY remains elusive. Here, we present a workflow for the characterization of RALY's interaction partners, termed iBioPQ, that involves in vivo biotinylation of biotin acceptor peptide (BAP)-fused protein in the presence of the prokaryotic biotin holoenzyme synthetase of BirA so that it can be purified using streptavidin-coated magnetic beads, circumventing the need for specific antibodies and providing efficient pulldowns. Protein eluates were subjected to tryptic digestion and identified using data-independent acquisition on an ion-mobility enabled high-resolution nanoUPLC-QTOF system. Using label-free quantification, we identified 143 proteins displaying at least 2-fold difference in pulldown compared to controls. Gene Ontology overrepresentation analysis revealed an enrichment of proteins involved in mRNA metabolism and translational control. Among the most abundant interacting proteins, we confirmed RNA-dependent interactions of RALY with MATR3, PABP1 and ELAVL1. Comparative analysis of pulldowns after RNase treatment revealed a protein-protein interaction of RALY with eIF4AIII, FMRP, and hnRNP-C. Our data show that RALY-containing RNPs are much more heterogeneous than previously hypothesized

A magnetic electron repeller to improve the ATHENA/WFI background level

The WFI is a DEPFET-based device developed at MPE as one of the two focal plane instruments for the next large ESA's mission for high energy astrophysics ATHENA. The expected level of instrumental background induced by the radiation environment in space is one of the parameters driving the camera design and it is required to be below 5∙10 cts/cm2 /sec/keV to enhance some of the unique observing capabilities of this detector. Background reduction can be obtained in a passive way by optimizing the detector shielding specifications (e.g. materials, thicknesses) and discarding frame regions affected by X-ray-like counts. In principle a higher rejection efficiency could be achieved with an active anticoincidence system surrounding the detector, in practice this cannot be done as it would make very complicated the camera readout and introduce dead-time. In this proceeding we discuss how a passive shielding against soft electrons with efficiency comparable to that of an active anticoincidence and no dead-time issue could be obtained by means of permanent magnets. We present results of a very preliminary feasibility study conducted in the framework of AHEAD and demonstrate theoretically the effectiveness of this solution. Nevertheless, an actual implementation would have as drawbacks an increased mass of the camera due to the presence of magnets and a potentially disturbing residual field in the detector environment

736–3 Costs and Complications of Non-thoracotomy Defibrillator Systems: Impact of Health Care Financing Administration Guidelines

Non-thoracotomy implantable defibrillator (ICD) systems have been shown to have lower costs and fewer complications than thoracotomy systems. Recent interpretation of Health Care Financing Administration regulations has challenged reimbursement for investigational devices or combinations of components not approved by the Food and Drug Administration (“off-label”). We compared the costs and complications associated with approved pulse generator/lead systems (CPI 1600/Endotak, CPl 1705/Endotak and Medtronic 7217/Transvene, n=136) with investigational and “off-label” systems (CPI 1625/Endotak, CPI 1715/Endotak, Medtronic 7219/Transvene and Ventritex V100 or V110/TVL and Vl00/Endotak, n=79). Age [63±12 years versus 63±11 years (mean±SD)] and ejection fraction (31±15% versus 31±11%) were similar for patients with approved and investigational systems, respectively. However, total hospital charges including preoperative care and evaluation, implant procedure and hardware, postoperative testing and revisions were $64±19,000 for approved devices versus$57±16,000 for non-approved devices (p=0.02) despite higher overall costs of newer pulse generators and leads. Total length of stay was 17±10 days versus 14±8 days (p=0.03) and complications including lead dislodgement, increased defibrillation threshold, hematoma and infection were 25/136 versus 4/77 (p<0.005) for approved and investigational or “off-label” systems, respectively. Based on data provided by the manufacturers, anticipated average battery longevity is 3.8 years for approved systems and 5.5 years for investigational or “off-label” systems.ConclusionsThe prudent use of current investigational or “off-label” nonthoracotomy ICD systems is more cost-effective and is associated with fewer complications than approved ICD systems. When increased battery longevity is considered, long term costs of non-thoracotomy ICD therapy may be improved dramatically with the use of investigational or “off-label” systems. Review of reimbursement regulations may be warranted