Spin-dependent Forward Particle Correlations in p+p Collisions at s=200\sqrt{s} = 200 GeV

The STAR collaboration has reported precision measurements of the transverse single spin asymmetries for the production of the $\pi^0$ mesons from polarized proton collisions at $\sqrt{s} = 200$ GeV. These measurements were obtained using modular forward detectors. The Forward Meson Spectrometer (FMS), covering a region of $2.5 < \eta < 4.0$, and its engineering prototype, provide increased acceptance, as needed for spin-dependent correlation studies that could disentangle contributions to the forward \$pi^0$ asymmetries. We report on the status of the analysis.Comment: 4 pages, 2 figures, to be published in the proceedings of the 18th International Spin Physics Symposium (SPIN2008), October 6-11, 2008, Charlottesville, Virginia, US

Positive Semidefiniteness and Positive Definiteness of a Linear Parametric Interval Matrix

We consider a symmetric matrix, the entries of which depend linearly on some parameters. The domains of the parameters are compact real intervals. We investigate the problem of checking whether for each (or some) setting of the parameters, the matrix is positive definite (or positive semidefinite). We state a characterization in the form of equivalent conditions, and also propose some computationally cheap sufficient\,/\,necessary conditions. Our results extend the classical results on positive (semi-)definiteness of interval matrices. They may be useful for checking convexity or non-convexity in global optimization methods based on branch and bound framework and using interval techniques

A36 Prevalence of HIV-1 subtypes in Slovenia with an emphasis on molecular and phylogenetic investigation of subtype A

21st International BioInformatics Workshop on Virus Evolution and Molecular EpidemiologyIn Slovenia, a small country in Central Europe, less than 1 per 1,000 inhabitants are estimated to be infected with HIV-1. As in most of the Central and Western European countries, the majority of patients diagnosed with HIV-1 are infected with subtype B. However, due to migration, other subtypes can become more prevalent in the country. The aim of this study was to determine HIV-1 subtypes circulating in Slovenia and to further examine the molecular epidemiology of subtype A. A total of 367 Slovenian HIV-1 sequences were included in the study, representing 58% of all patients diagnosed in Slovenia until the end of the year 2013. Subtype was assigned by employing different HIV subtyping tools coupled with Maximum likelihood phylogenetic analysis. The latter was performed to examine the molecular epidemiology of subtype A as well. Identified clusters of Slovenian subtype A sequences were further analyzed for the determination of the time of the most recent common ancestor (tMRCA) by using Monte Carlo Markov chain (MCMC) method available in BEAST 2.1.3 software. We determined the prevalence of subtype B to be 85.3%, while subtype A was the most prevalent non-B subtype found in 18 patients (4.9%), followed by CRF02_AG (2.4%), subtype C (1.1%), subtypes D, G and CRF01_AE (0.8% each) and subtypes F1 and CRF22_01A1 (0.3% each). Subtypes could not be assigned to 12 sequences (3.3%). The phylogenetic tree obtained by ML analysis of the subtype A and subtype A related recombinants revealed that Slovenian sequences were part of 6 major international clusters. Two clusters consisting only of Slovenian sequences were identified and thus additional MCMC analysis was employed. Results of a Slovenian cluster of 4 subtype A sequences showed a posterior probability value of 1 and a tMRCA between the years 1985 and 2008, with a mean in the year 2001. In conclusion, in a Central European country, where subtype B predominates, the second most common subtype was found to be subtype A. Non-B subtypes were observed in one out of seven patients in Slovenia, a fraction that is not negligible, thus proving importance of surveillance of HIV subtype diversity and corresponding molecular epidemiology of non-B subtypes.publishersversionpublishe

Značaj reproizvodnje u proizvodnji transmitera

This paper presents a algorithm for the improvement of the manufacturing process developed and tested for small-scale enterprise. The validity of the algorithm can be seen through: defining basic elements, defining environmental factors, the importance of resources, and the analysis of input and output in the manufacturing process. The algorithm incorporates implemented strategies: remanufacturing and 4Rs. The paper analyzed the temperature transmitter at the end of its life circle. Reuse transmitter is realized through: checking, disassembly, replacement parts, cleaning, re-assembling and testing. The work provides an example of how to save energy and materials which appear as large losses in the manufacturing process.ovom radu prikazan je algoritam za obezbeđenje unapređenja procesa proizvodnje u preduzeću maloserijskog tipa proizvodnje. Verodostojnost algoritma se ogleda kroz: definisanje osnovnih elemenata, definisanje faktora okruženja, značaj resursa, analizu ulaza i izlaza u procesu proizvodnje. Algoritam u sebi sadrži implementirane strategije: reproizovdnju i 4R. U radu analiziran je transmiter temperature na kraju životnog veka. Ponovna upotreba transmitera se realizuje kroz: proveru, rastavljanje, zamenu delova, čišćenje, ponovno sastavljenje i testiranje. Rad daje primer kako uštedeti na materijalu i energiji koji se javljaju kao veliki gubici u procesu proizvodnje

Event-shape and multiplicity dependence of freeze-out radii in pp collisions at √s = 7 TeV

Two-particle correlations in high-energy collision experiments enable the extraction of particle source radii by using the Bose-Einstein enhancement of pion production at low relative momentum q ∝ 1/R. It was previously observed that in pp collisions at √s = 7TeV the average pair transverse momentum kT range of such analyses is limited due to large background correlations which were attributed to mini-jet phenomena. To investigate this further, an event-shape dependent analysis of Bose-Einstein correlations for pion pairs is performed in this work. By categorizing the events by their transverse sphericity ST into spherical (ST &gt; 0:7) and jet-like (ST &lt; 0:3) events a method was developed that allows for the determination of source radii for much larger values of kT for the first time. Spherical events demonstrate little or no background correlations while jet-like events are dominated by them. This observation agrees with the hypothesis of a mini-jet origin of the non-femtoscopic background correlations and gives new insight into the physics interpretation of the kT dependence of the radii. The emission source size in spherical events shows a substantially diminished kT dependence, while jet-like events show indications of a negative trend with respect to kT in the highest multiplicity events. Regarding the emission source shape, the correlation functions for both event sphericity classes show good agreement with an exponential shape, rather than a Gaussian one

Measurement of pion, kaon and proton production in proton-proton collisions at s=7\sqrt{s}=7 TeV

The measurement of primary $\pi^{\pm}$, K$^{\pm}$, p and $\overline{p}$ production at mid-rapidity ($|y| <$ 0.5) in proton-proton collisions at $\sqrt{s} = 7$ TeV performed with ALICE (A Large Ion Collider Experiment) at the Large Hadron Collider (LHC) is reported. Particle identification is performed using the specific ionization energy loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/$c$ for pions, from 0.2 up to 6 GeV/$c$ for kaons and from 0.3 up to 6 GeV/$c$ for protons. The measured spectra and particle ratios are compared with QCD-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.Comment: 33 pages, 19 captioned figures, 3 tables, authors from page 28, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/156

Persistence of frequently transmitted drug-resistant HIV-1 variants can be explained by high viral replication capacity

Background: In approximately 10% of newly diagnosed individuals in Europe, HIV-1 variants harboring transmitted drug resistance mutations (TDRM) are detected. For some TDRM it has been shown that they revert to wild type while other mutations persist in the absence of therapy. To understand the mechanisms explaining persistence we investigated the in vivo evolution of frequently transmitted HIV-1 variants and their impact on in vitro replicative capacity. Results: We selected 31 individuals infected with HIV-1 harboring frequently observed TDRM such as M41L or K103N in reverse transcriptase (RT) or M46L in protease. In all these samples, polymorphisms at non-TDRM positions were present at baseline (median protease: 5, RT: 6). Extensive analysis of viral evolution of protease and RT demonstrated that the majority of TDRM (51/55) persisted for at least a year and even up to eight years in the plasma. D