3,665 research outputs found
TRT Alignment For SR1 Cosmics and Beyond
We present an algorithm for the alignment of the ATLAS Inner Detector, developed for the analysis of cosmics data taken with the ID barrel in SR1 in the summer of 2006. Our results include a comparison of the relative SCT-TRT alignment with survey measurements, a study of the alignment of SCT and TRT module positions and TRT module deformations, and a comparison of the `local' and `global' methods for alignment
Alignment of LHCb tracking stations with tracks fitted with a Kalman filter
The LHCb detector, operating at the Large Hadron Collider at CERN, is a single arm spectrometer optimized for the detection of the forward b anti-b production for b physics studies. The reconstruction of vertices and tracks is done by silicon micro-strips and gaseous straw-tube based detectors. In order to achieve good mass resolution for resonances the tracking detectors should be aligned to a precision of the order of ten microns. A software framework has been developed to achieve these goals and has been tested in various configurations. After a description of the software, we present alignment results and show in particular for the first time that a global solving for alignment using a locally parameterized track trajectory can be achieved
First studies of T-station alignment with simulated data
The alignment of the tracking stations using tracks fitted using standard LHCb track fit is studied. The procedure is presented together with two examples using simulated data. The first scenario presents the alignment of the IT and OT layers using beam-gas events at 450~GeV with no magnetic field. The second scenario is the alignment of the OT layers and IT boxes, layers and ladders with magnet-on data using minimum bias events at nominal energy. The results are validated by refitting J/ tracks using the misaligned geometry compared to the re-aligned case as well as the default. It is shown that after alignment the J mass resolution is degraded by at most 3~\%
Curcumin as Treatment for Bladder Cancer : A Preclinical Study of Cyclodextrin-Curcumin Complex and BCG as Intravesical Treatment in an Orthotopic Bladder Cancer Rat Model
Objective. To evaluate the antitumor effect of cyclodextrin-curcumin complex (CDC) on human and rat urothelial carcinoma cells in vitro and to evaluate the effect of intravesical instillations of CDC, BCG, and the combination in vivo in the AY-F344 orthotopic bladder cancer rat model. Curcumin has anticarcinogenic activity on urothelial carcinoma and is therefore under investigation for the treatment of non-muscle invasive bladder cancer. Curcumin and BCG share immunomodulating pathways against urothelial carcinoma. Methods. Curcumin was complexed with cyclodextrin to improve solubility. Four human urothelial carcinoma cell lines and the AY-27 rat cell line were exposed to various concentrations of CDC in vitro. For the in vivo experiment, the AY-27 orthotopic bladder cancer F344 rat model was used. Rats were treated with consecutive intravesical instillations of CDC, BCG, the combination of CDC+BCG, or NaCl as control. Results. CDC showed a dose-dependent antiproliferative effect on all human urothelial carcinoma cell lines tested and the rat AY-27 urothelial carcinoma cell line. Moreover, intravesical treatment with CDC and CDC+BCG results in a lower percentage of tumors (60% and 68%, respectively) compared to BCG (75%) or control (85%). This difference with placebo was not statistically significant (p=0.078 and 0.199, respectively). However, tumors present in the placebo and BCG-treated rats were generally of higher stage. Conclusions. Cyclodextrin-curcumin complex showed an antiproliferative effect on human and rat urothelial carcinoma cell lines in vitro. In the aggressive orthotopic bladder cancer rat model, we observed a promising effect of CDC treatment and CDC in combination with BCG.Peer reviewe
Characterization and comparison of smokeless powders by on-line two-dimensional liquid chromatography
Smokeless powders (SPs) are one of the most commonly used propellants for ammunition but can also be abused as energetic material in improvised explosive devices (IEDs) such as pipe bombs. After a shooting or explosion, unburnt or partially burnt particulates may be observed which can be used for forensic investigation. SPs comprise mainly nitrocellulose (NC) and additives. Therefore, the characterization of both NC and the additives is of significant forensic importance. Typically, the identification, classification, and chemical profiling of smokeless powders are based exclusively on the analysis of the additives. In this study, information regarding the NC base component was combined with the chemical analysis of the additives using two-dimensional liquid chromatography (2D-LC). The system combines size-exclusion chromatography (SEC) and reversed-phase liquid chromatography (RPLC) in an on-line heart-cut 2D-LC configuration. In the first dimension, the NC is characterized by its molecular-weight distribution (MWD) while being separated from the additives. The additives are then transferred to the second-dimension separation using a novel analyte-transfer system. In the second dimension, the additives are separated to obtain a detailed profile of the low-molecular-mass compounds in the SP. With this approach, the MWD of the NC and the composition of the additives in SP have been obtained within an hour. A discrimination power of 90.53% was obtained when studying exclusively the NC MWD, and 99.47% for the additive profile. This novel combination enables detailed forensic comparison of intact SPs. Additionally, no extensive sample preparation is required, making the developed method less labor intensive
Improved performance of the LHCb Outer Tracker in LHC Run 2
The LHCb Outer Tracker is a gaseous detector covering an area of with 12 double layers of straw tubes. The performance of the detector is
presented based on data of the LHC Run 2 running period from 2015 and 2016.
Occupancies and operational experience for data collected in , pPb and
PbPb collisions are described. An updated study of the ageing effects is
presented showing no signs of gain deterioration or other radiation damage
effects. In addition several improvements with respect to LHC Run 1 data taking
are introduced. A novel real-time calibration of the time-alignment of the
detector and the alignment of the single monolayers composing detector modules
are presented, improving the drift-time and position resolution of the detector
by 20\%. Finally, a potential use of the improved resolution for the timing of
charged tracks is described, showing the possibility to identify low-momentum
hadrons with their time-of-flight.Comment: 29 pages, 20 figures, minor changes to match the published versio
The combined use of steroids and immune checkpoint inhibitors in brain metastasis patients:a systematic review and meta-analysis
BACKGROUND: Immune checkpoint inhibitors (ICI) have been a breakthrough for selected cancer patients, including those with brain metastases (BMs). Likewise, steroids have been an integral component of symptomatic management of BM patients. However, clinical evidence on the interaction between ICI and steroids in BM patients is conflicting and has not adequately been summarized thus far. Hence, the aim of this study was to perform a systematic literature review and meta-analysis on the association between steroid use and overall survival (OS) in BM patients receiving ICI. METHODS: A systematic literature search was performed. Pooled effect estimates were calculated using random-effects models across included studies. RESULTS: After screening 1145 abstracts, 15 observational studies were included. Fourteen studies reported sufficient data for meta-analysis, comprising 1102 BM patients of which 32.1% received steroids. In the steroid group, median OS ranged from 2.9 to 10.2 months. In the nonsteroid group, median OS ranged from 4.9 to 25.1 months. Pooled results demonstrated significantly worse OS (HR = 1.84, 95% CI 1.22-2.77) and systemic progression-free survival (PFS; HR = 2.00, 95% CI 1.37-2.91) in the steroid group. Stratified analysis showed a consistent effect across the melanoma subgroup; not in the lung cancer subgroup. No significant association was shown between steroid use and intracranial PFS (HR = 1.31, 95% CI 0.42-4.07). CONCLUSIONS: Administration of steroids was associated with significantly worse OS and PFS in BM patients receiving ICI. Further research on dose, timing, and duration of steroids is needed to elucidate the cause of this association and optimize outcomes in BM patients receiving ICI
The Discovery Potential of a Super B Factory
The Proceedings of the 2003 SLAC Workshops on flavor physics with a high
luminosity asymmetric e+e- collider. The sensitivity of flavor physics to
physics beyond the Standard Model is addressed in detail, in the context of the
improvement of experimental measurements and theoretical calculations.Comment: 476 pages. Printed copies may be obtained by request to
[email protected] . arXiv admin note: v2 appears to be identical to v
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