University of Rijeka

About: University of Rijeka is a education organization based out in Rijeka, Croatia. It is known for research contribution in the topics: Population & Tourism. The organization has 3471 authors who have published 7993 publications receiving 110386 citations. The organization is also known as: Rijeka University & Sveučilište u Rijeci.

MAGIC TeV Gamma-Ray Observations of Markarian 421 during Multiwavelength Campaigns in 2006

Abstract: The Major Atmospheric Gamma Imaging Cerenkov (MAGIC) telescope participated in three multiwavelength (MWL) campaigns, observing the blazar Markarian (Mkn) 421 during the nights of 2006 April 28, 29, and 2006 June 14. We analyzed the corresponding MAGIC very-high energy observations during 9 nights from 2006 April 22 to 30 and on 2006 June 14. We inferred light curves with sub-day resolution and night-by-night energy spectra. A strong gamma-ray signal was detected from Mkn 421 on all observation nights. The flux (E > 250 GeV) varied on night-by-night basis between (0.92+-0.11)10^-10 cm^-2 s^-1 (0.57 Crab units) and (3.21+-0.15)10^-10 cm^-2 s^-1 (2.0 Crab units) in 2006 April. There is a clear indication for intra-night variability with a doubling time of 36+-10(stat) minutes on the night of 2006 April 29, establishing once more rapid flux variability for this object. For all individual nights gamma-ray spectra could be inferred, with power-law indices ranging from 1.66 to 2.47. We did not find statistically significant correlations between the spectral index and the flux state for individual nights. During the June 2006 campaign, a flux substantially lower than the one measured by the Whipple 10-m telescope four days later was found. Using a log-parabolic power law fit we deduced for some data sets the location of the spectral peak in the very-high energy regime. Our results confirm the indications of rising peak energy with increasing flux, as expected in leptonic acceleration models.

Very high-energy gamma-ray follow-up program using neutrino triggers from IceCube

Abstract: We describe and report the status of a neutrino-triggered program in IceCube that generates real-time alerts for gamma-ray follow-up observations by atmospheric-Cherenkov telescopes (MAGIC and VERITAS). While IceCube is capable of monitoring the whole sky continuously, high-energy gamma-ray telescopes have restricted fields of view and in general are unlikely to be observing a potential neutrino-flaring source at the time such neutrinos are recorded. The use of neutrino-triggered alerts thus aims at increasing the availability of simultaneous multi-messenger data during potential neutrino flaring activity, which can increase the discovery potential and constrain the phenomenological interpretation of the high-energy emission of selected source classes (e.g. blazars). The requirements of a fast and stable online analysis of potential neutrino signals and its operation are presented, along with first results of the program operating between 14 March 2012 and 31 December 2015.

Croatian physicians’ and nurses’ experience with ethical issues in clinical practice

Abstract: To assess ethical issues in everyday clinical practice among physicians and nurses of the University Hospital Rijeka, Croatia. We surveyed the entire population of internal medicine, oncology and intensive care specialists and associated nurses employed at the University Hospital Rijeka, Croatia (N=532). An anonymous questionnaire was used to explore the type and frequency of ethical dilemmas, rank of their difficulty, access and usage of ethics support services, training in ethics, and confidence about knowledge in ethics. Physicians (N=113, female 55%) ranged in age from 27 to 61, nurses (N=251, female 95%) ranged in age from 20 to 52. Most often ethical dilemmas were: uncertain or impaired decision-making capacity (physicians 66%, nurses 47%, P=0, 008), limitation of therapy at the end of life (physicians 60%, nurses 31%, P<0, 001), and disagreements among family members (physicians 47%, nurses 31%, P=0, 025). Most difficult ethical dilemmas were euthanasia/PAS (physicians 49%, nurses 52%) and limitation of therapy at the end of life (physicians 14%, nurses 18%). Only a minority reported ever using any kind of ethics support services (physicians 12%, nurses 3%, P=0, 001), or being very confident about knowledge in ethics (physicians 5%, nurses 6%). Similar ethical difficulties are present in clinical practice of both physicians and nurses, with important differences in access and usage of ethics support services. A need for systematic ethics educational activities was identified. Inclusion of individual ethics consultants in Croatian healthcare ethics support services is strongly advised.

Axial gravity, massless fermions and trace anomalies

Abstract: This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones.

Physiological role of IL-15 and IL-18 at the maternal-fetal interface.

Abstract: We review recent studies of two cytokines IL-15 and IL-18, showing that they are the critical cytokines controlling uterine NK cell cytokine production and cytolytic potential. Further, IL-15 has been implicated in differentiation and proliferation of uterine NK cells, while IL-18 enhanced innate immunity and both Th1- and Th2-driven immune responses depending on the cytokine milieu. We addressed the possible role of these two cytokines in induction of the IFN-gamma production as a key molecule in vascular remodeling during early pregnancy.