Jan Kochanowski University

About: Jan Kochanowski University is a education organization based out in Kielce, Poland. It is known for research contribution in the topics: Population & Redshift survey. The organization has 1319 authors who have published 3979 publications receiving 41536 citations. The organization is also known as: Jan Kochanowski University in Kielce & Uniwersytet Jana Kochanowskiego w Kielcach.

The VIMOS Public Extragalactic Redshift Survey (VIPERS): galaxy segregation inside filaments at z ≃ 0.7

Abstract: We present the first quantitative detection of large-scale filamentary structure at z ≃ 0.7 in the large cosmological volume probed by the VIMOS Public Extragalactic Redshift Survey (VIPERS). We use simulations to show the capability of VIPERS to recover robust topological features in the galaxy distribution, in particular the filamentary network. We then investigate how galaxies with different stellar masses and stellar activities are distributed around the filaments, and find a significant segregation, with the most massive or quiescent galaxies being closer to the filament axis than less massive or active galaxies. The signal persists even after downweighting the contribution of peak regions. Our results suggest that massive and quiescent galaxies assemble their stellar mass through successive mergers during their migration along filaments towards the nodes of the cosmic web. On the other hand, low-mass star-forming galaxies prefer the outer edge of filaments, a vorticity-rich region dominated by smooth accretion, as predicted by the recent spin alignment theory. This emphasizes the role of large-scale cosmic flows in shaping galaxy properties.

Effects of saponins against clinical E. coli strains and eukaryotic cell line

Abstract: Saponins are detergent-like substances showing antibacterial as well as anticancer potential. In this study, the effects of saponins from Quillaja saponaria were analyzed against prokaryotic and eukaryotic cells. Multidrug-resistant clinical E. coli strains were isolated from human urine. As eukaryotic cells, the CHO-K1 cell lines were applied. Antibacterial effect of ampicillin, streptomycin, and ciprofloxacin in the presence of saponins was measured by cultivation methods. Properties of saponins against CHO-K1 cells were measured by the MTT test, hemolysis assay and flow cytometry. Saponin from Quillaja saponaria has a cytotoxic effect at concentrations higher than 25 μg/mL and in the range of 12–50 μg/mL significantly increases the level of early apoptotic cells. Saponin at dose of 12 μg/mL enhances the six E. coli strains growth. We postulate that saponins increase the influx of nutrients from the medium into E. coli cells. Saponins do not have synergetic effects on antibacterial action of tested antibiotics. In contrary, in the presence of saponins and antibiotics, more CFU/mL E. coli cells were observed. This effect was similar to saponins action alone towards E. coli cells. In conclusion, saponins was cytotoxic against CHO-K1 cells, whereas against E. coli cells this effect was not observed.

Is f 0 ( 1710 ) a glueball

Abstract: We study the three-flavor chirally and dilatation invariant extended linear sigma model with (pseudo)scalar and (axial-)vector mesons as well as a scalar dilaton field whose excitations are interpreted as a glueball. The model successfully describes masses and decay widths of quark-antiquark mesons in the low-energy region up to 1.6 GeV. Here we study in detail the vacuum properties of the scalar-isoscalar J P C = 0 + + channel and find that (i) a narrow glueball is only possible if the vacuum expectation value of the dilaton field is (at tree level) quite large (i.e. larger than what lattice QCD and QCD sum rules suggest) and (ii) only solutions in which f 0 ( 1710 ) is predominantly a glueball are found. Moreover, the resonance f 0 ( 1370 ) turns out to be mainly ( u ¯ u + d ¯ d ) / 2 and thus corresponds to the chiral partner of the pion, while the resonance f 0 ( 1500 ) is mainly s ¯ s .

Strongly intensive quantities

Abstract: Analysis of fluctuations of hadron production properties in collisions of relativistic particles profits from use of measurable intensive quantities which are independent of system size variations. The first family of such quantities was proposed in 1992; another is introduced in this paper. Furthermore we present a proof of independence of volume fluctuations for quantities from both families within the framework of the grand canonical ensemble. These quantities are referred to as strongly intensive ones. Influence of conservation laws and resonance decays is also discussed.