Gaseous detectors based on large-size GEM-foils are planned to be used for a variety of upgrades and new experiments using high-rate and high-intensity particle beams. An excellent quality control of ...GEM-foils is a mandatory prerequisite to select the best foils for the assembly of a GEM detector. The high voltage stability of the foils is here of uppermost importance. In particular discharges that occur at the same position need to be detected. A spark detection system has been developed to automatically detect and record the time and position of sparks. The system is based on a commercial web camera installed in a housing for the tests and a custom-made, LabVIEW-based software for control and operation. An automatic Spark-Detection System for GEM foils was designed, built and characterized. It is able to detect and record discharges in large-size GEM foils during the quality control procedure. The spark detection e ciency was estimated to be higher than 97 %, the position resolution was determined to be approximately 0.5 mm. With this system, the characterization of GEM foils can be standardized to a much greater degree than before.
With the planned upgrade of the ALICE Time Projection Chamber (TPC) the current readout technology will be replaced by a Gas Electron Multiplier (GEM)-based readout technology in order to allow for a ...continuous operation at high interaction rates up to 50 kHz. A stack of four GEM stages with non-standard field configuration was chosen to achieve a suppression of the ion backflow below 1%, while maintaining a good energy resolution below sigma / E= \unit12% for super(55) Fe. A discharge probability of 10 super(-10) for alpha-particles was confirmed for this low ion backflow field configuration. This is comparable to standard triple GEM detectors in low discharge settings. To upgrade all the Inner and Outer Readout Chambers of ALICE, 576 GEM foils will be needed. Only GEM foils that fullfill the highest quality criteria can be used. Therefore a quality assurance scheme has been developed that includes a large set of quality assurance measurements.
The results of a clinico-laboratory evaluation of general response of cancer patients to antitumor therapy, including modificators, are considered. Also, applications of some procedures as guides to ...prognosis as well as the results of studies bacterial immunity and methods of its stimulation to prevent purulent complications in cancer patients are discussed.
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