The KASCADE-Grande experiment Apel, W.D.; Arteaga, J.C.; Badea, A.F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2010, Letnik:
620, Številka:
2
Journal Article
Recenzirano
KASCADE-Grande is the enlargement of the KASCADE extensive air shower detector, realized to expand the cosmic ray studies from the previous 10
14–10
17
eV primary energy range to 10
18
eV. This is ...performed by extending the area covered by the KASCADE electromagnetic array from 200×200 to 700×700
m
2 by means of 37 scintillator detector stations of 10
m
2 area each. This new array is named Grande and provides measurements of the all-charged particle component of extensive air showers (
N
ch
), while the original KASCADE array particularly provides information on the muon content
(
N
μ
)
. Additional dense compact detector set-ups being sensitive to energetic hadrons and muons are used for data consistency checks and calibration purposes. The performance of the Grande array and its integration into the entire experimental complex is discussed. It is demonstrated that the overall observable resolutions are adequate to meet the physical requirements of the measurements, i.e. primary energy spectrum and elemental composition studies in the primary cosmic ray energy range of 10
16–10
18
eV.
State based analysis of stochastic models for performance and dependability often requires the computation of the stationary distribution of a multidimensional continuous-time Markov chain (CTMC). ...The infinitesimal generator underlying a multidimensional CTMC with a large reachable state space can be represented compactly in the form of a block matrix in which each nonzero block is expressed as a sum of Kronecker products of smaller matrices. However, solution vectors used in the analysis of such Kronecker-based Markovian representations require memory proportional to the size of the reachable state space. This implies that memory allocated to solution vectors becomes a bottleneck as the size of the reachable state space increases. Here, it is shown that the hierarchical Tucker decomposition (HTD) can be used with adaptive truncation strategies to store the solution vectors during Kronecker-based Markovian analysis compactly and still carry out the basic operations including vector–matrix multiplication in Kronecker form within Power, Jacobi, and Generalized Minimal Residual methods. Numerical experiments on multidimensional problems of varying sizes indicate that larger memory savings are obtained with the HTD approach as the number of dimensions increases.
Solitary fibrous tumor (SFT) is a spindle cell neoplasm of mesenchymal origin. First reported in 1931, the pleura is the most common localization of SFT, and it’s exceptionally rare in the kidney. ...Overall, it represents less than 2% of all soft tissue tumors. In most cases, renal SFT (rSFT) presents with hematuria, flank pain, and a palpable mass. To our knowledge, less than 112 cases of rSFT have been reported. We report a case of rSFT of a 30-year-old male thought to be a renal cell carcinoma (RCC). Radical nephrectomy (RN) was done to remove a large right-sided mass invading the inferior vena cava. Immunohistochemistry confirmed the diagnosis of SFT showing positivity for CD34, CD99, and Bcl-2 protein, with no staining for cytokeratin. A post-operative CT (15 months) showed tumor recurrence in the renal compartment with huge inferior vena cava thrombus extending to the external iliac veins. With this case, we illustrate and highlight the importance of this diagnosis because of the uncertain biological behavior and prognosis of these tumors.
The treatment of caliceal diverticulum and deeply secluded lower-pole stones is challenging, and the indications are controversial. This study assessed the changes in the quality of life (QoL) of ...patients undergoing percutaneous nephrolithotomy (PCNL) for symptomatic caliceal diverticula and deep lower-pole calculi to determine whether there is a change in the "bother factor" in order to improve treatment strategies for this group of patients.
Twenty-two patients undergoing PCNL were evaluated prospectively using the SF36 QoL questionnaire before and 6 weeks after PCNL. The results before and after PCNL were compared individually and by group and analyzed statistically. A P value <or=0.05 was considered significant.
Most (87%) of the patients were completely stone free after the procedure. Significant QoL findings were a reduction in symptoms interfering with performance at work (40%) and improved general health (33%). Although there was an overall improvement in QoL across the entire group, this reached statistical significance for only two of the seven domains of the questionnaire.
In spite of a high stone-free rate, fewer than half of patients benefited subjectively from the procedure in terms of improvement of QoL. Therefore, patients should be made aware of the limited impact of surgical treatment on QoL, and asymptomatic patients can be given the option of further watchful waiting.
Steinstrasse constitutes a potentially serious complication of extracorporeal shock-wave lithotripsy (SWL). Ureteral stent placement has been used to prevent Steinstrasse after fragmentation of ...larger stones. However, particularly more recently, its preventive efficacy has been questioned. The aim of this study therefore was to analyze the role of ureteral stent placement in the prevention of Steinstrasse.
We analyzed data of 1087 patients who had been treated with a Wolf Piezolith 2300 in the General Infirmary in Leeds/UK for stones ranging from 10 to 95 mm in diameter.
The incidence of Steinstrasse was 6.3%. The likelihood was significantly correlated with the stone size and was significantly less in patients with stones >20 mm if a stent had been inserted prior to SWL. Moreover, in these patients, the risk of acute clinical symptoms in the event of Steinstrasse was greatly reduced, and the treatment could be continued safely in the majority of cases (86%). Treatments of the Steinstrasse itself with SWL resulted in its clearance in most of the cases (78%). It was always possible to clear even extended persistent Steinstrasse by laser lithotripsy.
These results provide a clear indication for the pre-SWL insertion of a ureteral stent in patients with stones >20 mm in diameter. In the event of Steinstrasse, SWL of the collection should be tried before more invasive endourologic procedures are considered.
Abstract
Ultra-high-energy photons with energies exceeding 10
17
eV offer a wealth of connections to different aspects of cosmic-ray astrophysics as well as to gamma-ray and neutrino astronomy. The ...recent observations of photons with energies in the 10
15
eV range further motivate searches for even higher-energy photons. In this paper, we present a search for photons with energies exceeding 2 × 10
17
eV using about 5.5 yr of hybrid data from the low-energy extensions of the Pierre Auger Observatory. The upper limits on the integral photon flux derived here are the most stringent ones to date in the energy region between 10
17
and 10
18
eV.
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