This review addresses hidden costs associated with the Bayer VERSANT® assay, Roche AMPLICOR MONITOR® test and COBAS AMPLICOR MONITOR® test and how these influence the final per reportable cost to a ...testing laboratory in resource-rich and -poor countries. An in-depth evaluation and recommendation of the most cost-effective approach for these tests is presented. The analyses demonstrate the need for manufacturers to consider labor and supply costs when marketing a kit in resource-poor countries, noting that marketing strategies need to change. In the absence of any proven monitoring alternative, emphasis is placed on increasing market share to promote significant reduction in kit prices to suit the demands of markets in resource-poor countries. Finally, recommendations are made to improve the overall cost structure of viral load testing. This review is intended as a tool to optimize assay usage in attaining the lowest performance costs by assay and is not to endorse any test, as will become apparent.
The ATLAS Inner Detector consists of three sub-systems, the Pixel Detector at the innermost radius, the Semi-Conductor Tracker at intermediate radii, and the Transition Radiation Tracker (TRT) at the ...outermost radius in front of the electromagnetic calorimeter. The TRT provides a combination of continuous tracking with many projective measurements based on individual drift-tubes (or straws) and of electron identification based on radiator fibres or foils interleaved between the straws themselves. This paper describes the current status of design and construction of the various components of the TRT: the assembly of the barrel modules has recently been completed, that of the end-cap wheels is well underway, and the on-detector front-end electronics is in production. The detector modules and front-end electronics boards will be integrated together over the next year, the barrel and end-cap TRT parts will be assembled and tested with their SCT counterparts during 2005 and installation and commissioning in the ATLAS pit will take place at the end of 2005 and the beginning of 2006.
ATLAS Transition Radiation Tracker test-beam results Akesson, T.; Arik, E.; Baker, K. ...
2nd Workshop on Advanced Transition Radiation Detectors for Accelerator and Space Applications,Bari, Italy,2003-09-04 - 2003-09-07,
2004, Letnik:
522, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Several prototypes of the Transition Radiation Tracker for the ATLAS experiment at the LHC have been built and tested at the CERN SPS accelerator. Results from detailed studies of the straw-tube hit ...registration efficiency and drift-time measurements and of the pion and electron spectra without and with radiators are presented.
The transition radiation tracker (TRT) is one of the three subsystems of the inner detector of the ATLAS experiment. It is designed to operate for 10 yr at the LHC, with integrated charges of /spl ...sim/10 C/cm of wire and radiation doses of about 10 Mrad and 2/spl times/10/sup 14/ neutrons/cm/sup 2/. These doses translate into unprecedented ionization currents and integrated charges for a large-scale gaseous detector. This paper describes studies leading to the adoption of a new ionization gas regime for the ATLAS TRT. In this new regime, the primary gas mixture is 70%Xe-27%CO/sub 2/-3%O/sub 2/. It is planned to occasionally flush and operate the TRT detector with an Ar-based ternary mixture, containing a small percentage of CF/sub 4/, to remove, if needed, silicon pollution from the anode wires. This procedure has been validated in realistic conditions and would require a few days of dedicated operation. This paper covers both performance and aging studies with the new TRT gas mixture.
The Transition Radiation Tracker (TRT) sits at the outermost part of the ATLAS Inner Detector, encasing the Pixel Detector and the Semi-Conductor Tracker (SCT). The TRT combines charged particle ...track reconstruction with electron identification capability. This is achieved by layers of xenon-filled straw tubes with periodic radiator foils or fibers providing TR photon emission. The design and choice of materials have been optimized to cope with the harsh operating conditions at the LHC, which are expected to lead to an accumulated radiation dose of 10 Mrad and a neutron fluence of up to 2middot10 14 n/cm 2 after ten years of operation. The TRT comprises a barrel containing 52 000 axial straws and two end-cap parts with 320 000 radial straws. The total of 420 000 electronic channels (two channels per barrel straw) allows continuous tracking with many projective measurements (more than 30 straw hits per track). The assembly of the barrel modules in the US has recently been completed, while the end-cap wheel construction in Russia has reached the 50% mark. After testing at the production sites and shipment to CERN, all modules and wheels undergo a series of quality and conformity measurements. These acceptance tests survey dimensions, wire tension, gas-tightness, high-voltage stability and gas-gain uniformity along each individual straw. This paper gives details on the acceptance criteria and measurement methods. An overview of the most important results obtained to-date is also given
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