Nontrivial Deformation of a Trivial Bundle

The ${\rm SU}(2)$-prolongation of the Hopf fibration $S^3\to S^2$ is a trivializable principal ${\rm SU}(2)$-bundle. We present a noncommutative deformation of this bundle to a quantum principal ${\rm SU}_q(2)$-bundle that is not trivializable. On the other hand, we show that the ${\rm SU}_q(2)$-bundle is piecewise trivializable with respect to the closed covering of $S^2$ by two hemispheres intersecting at the equator.Comment: The present paper has been extracted from an earlier version of arXiv:1101.0201, so that there are some overlaps in introductory parts and standard definition

The K-theory of twisted multipullback quantum odd spheres and complex projective spaces

We find multipullback quantum odd-dimensional spheres equipped with natural $U(1)$-actions that yield the multipullback quantum complex projective spaces constructed from Toeplitz cubes as noncommutative quotients. We prove that the noncommutative line bundles associated to multipullback quantum odd spheres are pairwise stably non-isomorphic, and that the $K$-groups of multipullback quantum complex projective spaces and odd spheres coincide with their classical counterparts. We show that these $K$-groups remain the same for more general twisted versions of our quantum odd spheres and complex projective spaces.Comment: The proof of Theorem 0.1(3) corrected, 35 pages. To appear in Journal of Noncommutative Geometr

Studies on magnetic properties of unique molecular magnet {[FeII(pyrazole)4]2[NbIV(CN)8]⋅4H2O}n\{[Fe^{II}(pyrazole)_4]_2[Nb^{IV}(CN)_8]\cdot4H_2O\}_n

In this paper magnetic properties of hybrid inorganic-organic compound {[FeII(pyrazole)4]2[NbIV(CN)8]∙4H2O}n are presented. This is a three dimensional molecular magnet with well localized magnetic moments, which make it a suitable candidate for testing magnetic models. In order to characterize the magnetic properties of the above compound we performed the AC/DC magnetometry in the range 0-5 T. The special attention was paid to the phase transition at 7.9 K. The study in magnetic field supports magnetic ordering below 7.9 K

Cytological response of palatal epithelium to TiN-coated CoCr alloy denture

The aim of this study was to assess the impact of titanium nitride coatings on CoCr alloy metal parts in framework dentures on human palatal epithelium cytology compared to framework dentures made with the same alloy but without titanium nitride coating, and to acrylic dentures. Every prosthetic restoration introduced into the oral cavity and remaining in direct contact with the palate exhibits a varied and harmful effect on the state of the palatal epithelium by disturbing its keratinization. CoCr alloy dentures produce a significantly greater perturbation of keratinization compared to acrylic dentures. There is no evidence showing that a titanium nitride coating of the CoCr alloy plays a protective role in the environment of the oral cavity

The connective tissue response to Ti, NiCr and AgPd alloys.

The aim of the study was to compare the connective tissue response of Lewis rats to Ti, NiCr and AgPd alloys. It was found that implants were covered by collagen-rich, well vascularized capsules. Titanium was covered by the thinnest capsule (57 Âą 20 Îźm) and AgPd alloy was covered by the thickest capsule (239 Âą 50 Îźm). The PCNA+ cell prevalence in the capsules was lower for titanium than for AgPd and NiCr. Mast cells formed a gradient to a depth of 1200 Îźm only for titanium implants. Cells with brown to black silver granules in the cytoplasm were observed close to AgPd implants. The results suggest that titanium implants induce a weaker connective tissue response than implants made from NiCr and AgPd alloys

Normative Values for Heart Rate Variability Parameters in School-Aged Children: Simple Approach Considering Differences in Average Heart Rate

Background: Heart rate variability (HRV) analysis is a clinical tool frequently used to characterize cardiac autonomic status. The aim of this study was to establish normative values for short-term HRV parameters by considering their main determinants in school-aged children.Methods: Five-minute electrocardiograms were taken from 312 non-athlete children (153 boys) at age of 6 to 13 years for computation of conventional time- and frequency-domain HRV parameters. Heart rate (HR), respiratory rate, age, body mass index, and sex were considered as their potential determinants. Multiple regression analysis revealed that HR was the principal predictor of all standard HRV indices. To develop their universal normative limits, standard HRV parameters were corrected for prevailing HR.Results: The HRV correction for HR yielded the parameters which became independent on both sex and HR, and only poorly dependent on age (with small effect size). Normal ranges were calculated for both time- and frequency-domain indices (the latter computed with either fast Fourier transform and autoregressive method). To facilitate recalculation of standard HRV parameters into corrected ones, a calculator was created and attached as a Supplementary Material that can be downloaded and used for both research and clinical purposes.Conclusion: This study provides HRV normative values for school-aged children which have been developed independently of their major determinants. The calculator accessible in the Supplementary Material can considerably simplify determination if HRV parameters accommodate within normal limits

Analysis procedure of the positronium lifetime spectra for the J-PET detector

Positron Annihilation Lifetime Spectroscopy (PALS) has shown to be a powerful tool to study the nanostructures of porous materials. Positron Emissions Tomography (PET) are devices allowing imaging of metabolic processes e.g. in human bodies. A newly developed device, the J-PET (Jagiellonian PET), will allow PALS in addition to imaging, thus combining both analyses providing new methods for physics and medicine. In this contribution we present a computer program that is compatible with the J-PET software. We compare its performance with the standard program LT 9.0 by using PALS data from hexane measurements at different temperatures. Our program is based on an iterative procedure, and our fits prove that it performs as good as LT 9.0.Comment: 4 figures, 8 page

Long-term allogeneic hematopoietic cells transplantation survivors proinflammatory cytokine profile compared to their respective donors and immunophenotype differences depending on GvHD history and infection status

Background In the course of allogeneic hematopoietic cell transplantation (allo-HCT) the donor’s hematopoietic progenitor cells are exposed to immense proliferative stress to reconstitute in the recipient the functional hematopoiesis. Moreover, recipients who develop infections or chronic GvHD are subjected to further proliferative stress, especially in the lymphocyte subset. We hypothesized that allo-HCT may induce changes in proinflammatory cytokines profile and immunophenotype in the allo-HCT recipients, especially in patients with cGVHD history. We compared the cytokine profile (Il-6, Il-10, and TNF-) between long-term allo-HCT recipients and their respective donors and we analyzed cytokines profile and the immunophenotype of lymphocytes in long-term recipients grouped according to the infection and GvHD history. Results We have found no differences in the proinflammatory cytokines between allo-HCT recipients and their respective donors, as well as between recipients grouped according to infectious risk status. Immunophenotyping of recipients grouped according to GvHD status revealed an increased percentage of B-cell presenting PD-1 in recipients without a history of GvHD. Conclusions Lack of differences in proinflammatory cytokines concentrations between recipients and donors of allo-HCT would suggest that allo-HCT does not induce acceleration of the inflammageing-resembling phenomenon. No differences in the cytokine profile and immunophenotype between recipients grouped according to infectious risk status suggest that infectious risk is not reflected by the immunophenotype and cytokine profile. Furthermore, the lack of significant differences in immunophenotype of the recipients grouped according to the history of GvHD may suggest that in long-term survivors the immune system tends to stabilize with time

Introduction of total variation regularization into filtered backprojection algorithm

In this paper we extend the state-of-the-art filtered backprojection (FBP) method with application of the concept of Total Variation regularization. We compare the performance of the new algorithm with the most common form of regularizing in the FBP image reconstruction via apodizing functions. The methods are validated in terms of cross-correlation coefficient between reconstructed and real image of radioactive tracer distribution using standard Derenzo-type phantom. We demonstrate that the proposed approach results in higher cross-correlation values with respect to the standard FBP method

A method to produce linearly polarized positrons and positronium atoms with the J-PET detector

A method for creating linearly polarized positrons and ortho-positronium (o-Ps) atoms with the J-PET detector is presented. The unique geometry and properties of the J-PET tomography enable one to design a positron source such that the quantization axis for the estimation of the linear polarization of produced o-Ps can be determined on the event by event basis in a direction of the positron motion. We intend to use ²²Na or other β⁺ decay isotopes as a source of polarized positrons. Due to the parity violation in the beta decay, the emitted positrons are longitudinally polarized. The choice of the quantization axis is based on the known position of the positron emitter and the reconstructed position of the positronium annihilation. We show that the J-PET tomography is equipped with all needed components