► All-particle energy spectrum of cosmic rays between knee and ankle is not a single power law. ► Just above 1016eV the spectrum exhibits a hardening. ► Around 8×1016eV there is a knee-like feature ...in the spectrum.
The energy spectrum of cosmic rays between 1016eV and 1018eV, derived from measurements of the shower size (total number of charged particles) and the total muon number of extensive air showers by the KASCADE-Grande experiment, is described. The resulting all-particle energy spectrum exhibits strong hints for a hardening of the spectrum at approximately 2·1016eV and a significant steepening at ≈8·1016eV. These observations challenge the view that the spectrum is a single power law between knee and ankle. Possible scenarios generating such features are discussed in terms of astrophysical processes that may explain the transition region from galactic to extragalactic origin of cosmic rays.
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.
Efficacy, safety, and cost implications are important considerations when choosing an ophthalmic treatment. Fixed-combination glaucoma medications containing brimonidine 0.2% and timolol 0.5%, or ...dorzolamide 2% and timolol 0.5%, were compared with brimonidine 0.2% and dorzolamide 2% that were used as adjunctive therapy to timolol 0.5%.
A literature review was conducted to determine the outcome parameters of intraocular pressure reduction and tolerability after 3 months of use of brimonidine or dorzolamide, each together with timolol as a fixed-combination or in concomitant therapy. Modelled cost-minimization and cost-effectiveness analyses were performed to investigate the economic consequences of ophthalmic therapy with brimonidine, dorzolamide, and timolol from a societal perspective.
The literature review found that brimonidine and dorzolamide used as fixed combinations with timolol as well as in adjunctive therapy to timolol were equally effective and safe. Furthermore, in the European countries studied, the fixed combination of brimonidine/timolol represented a less costly option when compared to the fixed combination of dorzolamide/timolol evaluated over both a 3-month and a 12-month horizon.
Brimonidine used as a fixed-combination therapy with timolol provided better cost value than dorzolamide/timolol in all the countries studied. For most countries, the fixed combination of brimonidine and timolol also provided better cost value than adjunctive therapy with brimonidine, which was more cost effective than adjunctive therapy with dorzolamide.
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.
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