2,486 research outputs found
Model independent analysis of nearly L\'evy correlations
A model-independent method for the analysis of the two-particle short-range
correlations is presented, that can be utilized to describe e.g. Bose-Einstein
(HBT), dynamical (ridge) or other correlation functions, that have a nearly
L\'evy or streched exponential shape. For the special case of L\'evy exponent
alpha = 1, the earlier Laguerre expansions are recovered, for the alpha = 2
special case, a new expansion method is obtained for nearly Gaussian
correlation functions. Multi-dimensional L\'evy expansions are also introduced
and their potential application to analyze rigde correlation data is discussed
Rapid deconvolution of low-resolution time-of-flight data using Bayesian inference
The deconvolution of low-resolution time-of-flight data has numerous advantages, including the ability to extract additional information from the experimental data. We augment the well-known Lucy-Richardson deconvolution algorithm using various Bayesian prior distributions and show that a prior of second-differences of the signal outperforms the standard Lucy-Richardson algorithm, accelerating the rate of convergence by more than a factor of four, while preserving the peak amplitude ratios of a similar fraction of the total peaks. A novel stopping criterion and boosting mechanism are implemented to ensure that these methods converge to a similar final entropy and local minima are avoided. Improvement by a factor of two in mass resolution allows more accurate quantification of the spectra. The general method is demonstrated in this paper through the deconvolution of fragmentation peaks of the 2,5-dihydroxybenzoic acid matrix and the benzyltriphenylphosphonium thermometer ion, following femtosecond ultraviolet laser desorption
Low molecular weight heparin-induced skin necrosis—a systematic review
Background: Low molecular weight heparins (LMWHs) are currently used as a standard for anti-thrombotic therapy. Skin necrosis caused by LMWH is a rare and probably under-reported complication. The aim of our systematic review is to analyse the present literature for cases of LMWH-induced skin necrosis, emphasising the pathogenesis, clinical pattern, and management of this rare side effect. Methods: We performed a Medline literature search (PubMed database) and manual cross-referencing to identify all articles related to LMWH-induced skin necrosis. Data were analysed for type of LMWH used, time until skin necrosis occurred, localisation, size, laboratory findings, switch anticoagulant, complications, and outcome. Additionally, the case of a patient from our hospital is presented. Results: We included a total of 20 articles (21 cases) reporting on LMWH-induced skin necrosis. Skin necrosis occurred locally and distant from the injection site. Heparin-induced antibodies were frequently observed (positive 9/11 articles, negative 2/11). However, severe thrombocytopenia (platelet count <100,000cells/ml) occurred in only four cases, while platelet count remained normal in 50% of the cases. After patients had been switched to other anti-thrombotic drugs, the clinical course was usually benign; however, reconstructive surgery was necessary in two cases. Conclusion: LMWH-induced skin necrosis may occur as part of the heparin-induced thrombocytopenia (HIT) syndrome, but other pathomechanisms, including allergic reactions and local trauma, may also be involved. When HIT is excluded, unfractionated heparin is a safe switch anticoagulant. Otherwise, non-heparin preparations such as hirudin or fondaparinux should be preferre
Charge Influence On Mini Black Hole's Cross Section
In this work we study the electric charge effect on the cross section
production of charged mini black holes (MBH) in accelerators. We analyze the
charged MBH solution using the {\it fat brane} approximation in the context of
the ADD model. The maximum charge-mass ratio condition for the existence of a
horizon radius is discussed. We show that the electric charge causes a decrease
in this radius and, consequently, in the cross section. This reduction is
negligible for protons and light ions but can be important for heavy ions.Comment: 4 pages, 0 figure. To be published in Int. J. Mod. Phys. D
Gaseous elemental mercury depletion events observed at Cape Point during 2007–2008
Gaseous mercury in the marine boundary layer has been measured with a 15 min temporal resolution at the Global Atmosphere Watch station Cape Point since March 2007. The most prominent features of the data until July 2008 are the frequent occurrences of pollution (PEs) and depletion events (DEs). Both types of events originate mostly within a short transport distance (up to about 100 km), which are embedded in air masses ranging from marine background to continental. The Hg/CO emission ratios observed during the PEs are within the range reported for biomass burning and industrial/urban emissions. The depletion of gaseous mercury during the DEs is in many cases almost complete and suggests an atmospheric residence time of elemental mercury as short as a few dozens of hours, which is in contrast to the commonly used estimate of approximately 1 year. The DEs observed at Cape Point are not accompanied by simultaneous depletion of ozone which distinguishes them from the halogen driven atmospheric mercury depletion events (AMDEs) observed in Polar Regions. Nonetheless, DEs similar to those observed at Cape Point have also been observed at other places in the marine boundary layer. Additional measurements of mercury speciation and of possible mercury oxidants are hence called for to reveal the chemical mechanism of the newly observed DEs and to assess its importance on larger scales
Considering the need for alternative intervention strategies for the management of diabetic policy formulation in South Africa
CITATION: Thomas, V. V., De Kock, I. H. & Bam, L. 2018. Considering the need for alternative intervention strategies for the management of diabetic policy formulation in South Africa. In SAIIE29 Proceedings, 24-26 October 2018, Spier, Stellenbosch, South Africa.The original publication is available at https://conferences.sun.ac.za/index.php/saiie29/saiie29/schedConf/presentationsENGLISH ABSTRACT: The increasing prevalence of diabetes in South Africa, alongside other non-communicable diseases, places a heavy burden on the health care system; especially when faced with the significant difference in quality of care between private and public health care, and the increased burden of disease. This paper analyses various diabetic policies already implemented in South Africa, and considers the need to investigate alternative policies and intervention strategies to manage diabetes in South Africa. Due to the complex nature and non-linear interactions which exist within the health care system, a system dynamics-based approach is suggested as a useful analysis tool to evaluate and understand the dominant factors that influence the effective management of diabetes to potentially inform more effective and efficient diabetic policy formulation.https://conferences.sun.ac.za/index.php/saiie29/saiie29/paper/view/3590Publisher's versio
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