Light-by-light scattering in ultraperipheral collisions of heavy ions with future FoCal and ALICE 3 detectors

We discuss possible future studies of photon-photon (light-by-light) scattering using a planned FoCal and ALICE 3 detectors. We include different mechanisms of $\gamma\gamma\to\gamma\gamma$ scattering, such as double-hadronic photon fluctuations, $t/u$-channel neutral pion exchange or resonance excitations ($\gamma \gamma \to R$) and deexcitation ($R \to \gamma \gamma$). The broad range of (pseudo)rapidities and lower cuts on transverse momenta open a necessity to consider not only dominant box contributions but also other subleading contributions. Here we include low mass resonant $R = \pi^0$, $\eta$, $\eta'$ contributions. The resonance contributions give intermediate photon transverse momenta. However, these contributions can be eliminated by imposing windows on di-photon invariant mass. We study and quantify individual box contributions (leptonic, quarkish). The electron/positron boxes dominate at low $M_{\gamma \gamma}<1$ GeV di-photon invariant masses. The PbPb$\to$PbPb$\gamma \gamma$ cross section is calculated within equivalent photon approximation in the impact parameter space. Several differential distributions are presented and discussed. We consider four different kinematic regions. We predict cross section in the (mb-b) range for typical ALICE 3 cuts, a few orders of magnitude larger than for the current ATLAS or CMS experiments. We also consider the two-$\pi^0$ background which can, in principle, be eliminated at the new kinematical range for the ALICE 3 measurements by imposing dedicated cuts on di-photon transverse momentum and\or so-called vector asymmetry.Comment: 20 pages, 19 Figures, 3 Tables; misprint corrected, 1 figure adde

A remark on the dimension of the Bergman space of some Hartogs domains

Let D be a Hartogs domain of the form D={(z,w) \in CxC^N : |w| < e^{-u(z)}} where u is a subharmonic function on C. We prove that the Bergman space of holomorphic and square integrable functions on D is either trivial or infinite dimensional.Comment: 12 page

FindFoci: a focus detection algorithm with automated parameter training that closely matches human assignments, reduces human inconsistencies and increases speed of analysis

Accurate and reproducible quantification of the accumulation of proteins into foci in cells is essential for data interpretation and for biological inferences. To improve reproducibility, much emphasis has been placed on the preparation of samples, but less attention has been given to reporting and standardizing the quantification of foci. The current standard to quantitate foci in open-source software is to manually determine a range of parameters based on the outcome of one or a few representative images and then apply the parameter combination to the analysis of a larger dataset. Here, we demonstrate the power and utility of using machine learning to train a new algorithm (FindFoci) to determine optimal parameters. FindFoci closely matches human assignments and allows rapid automated exploration of parameter space. Thus, individuals can train the algorithm to mirror their own assignments and then automate focus counting using the same parameters across a large number of images. Using the training algorithm to match human assignments of foci, we demonstrate that applying an optimal parameter combination from a single image is not broadly applicable to analysis of other images scored by the same experimenter or by other experimenters. Our analysis thus reveals wide variation in human assignment of foci and their quantification. To overcome this, we developed training on multiple images, which reduces the inconsistency of using a single or a few images to set parameters for focus detection. FindFoci is provided as an open-source plugin for ImageJ

Biological in-vivo measurement of dose distribution in patients' lymphocytes by gamma-H2AX immunofluorescence staining: 3D conformal- vs. step-and-shoot IMRT of the prostate gland

<p>Abstract</p> <p>Background</p> <p>Different radiation-techniques in treating local staged prostate cancer differ in their dose- distribution. Physical phantom measurements indicate that for 3D, less healthy tissue is exposed to a relatively higher dose compared to SSIMRT. The purpose is to substantiate a dose distribution in lymphocytes <it>in-vivo </it>and to discuss the possibility of comparing it to the physical model of total body dose distribution.</p> <p>Methods</p> <p>For each technique (3D and SSIMRT), blood was taken from 20 patients before and 10 min after their first fraction of radiotherapy. The isolated leukocytes were fixed 2 hours after radiation. DNA double-strand breaks (DSB) in lymphocytes' nuclei were stained immunocytochemically using the gamma-H2AX protein. Gamma-H2AX foci inside each nucleus were counted in 300 irradiated as well as 50 non-irradiated lymphocytes per patient. In addition, lymphocytes of 5 volunteer subjects were irradiated externally at different doses and processed under same conditions as the patients' lymphocytes in order to generate a calibration-line. This calibration-line assigns dose-value to mean number of gamma-H2AX foci/ nucleus. So the dose distributions in patients' lymphocytes were determined regarding to the gamma-H2AX foci distribution. With this information a cumulative dose-lymphocyte-histogram (DLH) was generated. Visualized distribution of gamma-H2AX foci, correspondingly dose per nucleus, was compared to the technical dose-volume-histogram (DVH), related to the whole body-volume.</p> <p>Results</p> <p>Measured <it>in-vivo </it>(DLH) and according to the physical treatment-planning (DVH), more lymphocytes resulted with low-dose exposure (< 20% of the applied dose) and significantly fewer lymphocytes with middle-dose exposure (30%-60%) during Step-and-Shoot-IMRT, compared to conventional 3D conformal radiotherapy. The high-dose exposure (> 80%) was equal in both radiation techniques. The mean number of gamma-H2AX foci per lymphocyte was 0.49 (3D) and 0.47 (SSIMRT) without significant difference.</p> <p>Conclusions</p> <p><it>In-vivo </it>measurement of the dose distribution within patients' lymphocytes can be performed by detecting gamma-H2AX foci. In case of 3D and SSIMRT, the results of this method correlate with the physical calculated total body dose-distribution, but cannot be interpreted unrestrictedly due to the blood circulation. One possible application of the present method could be in radiation-protection for <it>in-vivo </it>dose estimation after accidental exposure to radiation.</p

Model of the management of the budgeting and controlling process in the organizational entities of academic institutions

In this article, the tendencies of the development of financing and functioning of academic institutions on the present-day educational market are presented. The required changes are characterized in the way finances are managed with a particular consideration of public academic institutions. Proposals are provided in relation to the determination of standard revenues of the organizational entities of academic institutions, analysis methods of the costs of the functioning of these entities and the budgeting of their operation. Prospects are presented of the development of the controlling of the realization of the budgets of the organizational entities of academic institutions

Calculation model of teaching costs in a university

A calculation model of teaching costs in a university is a system of guidelines, notions and relations to facilitate an assessment of the costs generated by individual university departments, majors, subjects etc. The existing calculation models based on the assessment of costs with the use of precision data prove to be ineffective in practice. The major drawback of these systems is the fact that it is not possible to take into account non-precision data in relation to cost generating factors (e.g. the number of didactic groups, hourly rates etc.). This article presents the author’s own proposal of a cost calculation model based on the formalism of fuzzy logics (with the use of the L-R representation). On the basis of the model proposed, it is possible to assess the costs of an academic subject with imprecise information concerning cost generating factors, or the values of those factors are assessed which imply the values set of the cost of a subject

Synthesis and Characterization of Thermal Properties of Type Eu2O3-ZrO2 Sinters

The oxides with pyrochlore or defected fluorite structure are a potential alternative ceramic materials for now widely used yttria-stabilized zirconia 8YSZ in the application for the insulation layer of thermal barrier coatings systems. This paper presents a procedure of synthesis of europium zirconate of Eu2Zr2O7 type, by the method of high temperature sintering under pressure. The analysis of the effect of the powders` homogenization methods on homogeneity of final sintered material showed that the highest homogeneity can be obtained after mechanical mixing in alcohol. Moreover, the DSC investigation carried out on a mixture of powders before the sintering process and on the material after high temperature sintering under pressure, suggest the synthesis of a new phase an europium zirconate Eu2Zr2O7 with the pyrochlore structure. Obtained phase was characterized by stability over the entire range of tested temperature, i.e. to 1450°C. The resulting material based on europium zirconate has a lower coefficient of thermal diffusivity than the now widely used 8YSZ