Spectrum of elementary excitations in Galilean-invariant integrable models

The spectrum of elementary excitations in one-dimensional quantum liquids is generically linear at low momenta. It is characterized by the sound velocity that can be related to the ground state energy. Here we study the spectrum at higher momenta in Galilean invariant integrable models. Somewhat surprisingly, we show that the spectrum at arbitrary momentum is fully determined by the properties of the ground state. We find general exact relations for the coefficients of several terms in the expansion of the excitation energy at low momenta and arbitrary interaction and express them in terms of the Luttinger liquid parameter. We apply the obtained formulas to the Lieb-Liniger model and obtain several new results.Comment: 5 page

Fluctuation-induced noise in out-of-equilibrium disordered superconducting films

We study out-of-equilibrium transport in disordered superconductors close to the superconducting transition. We consider a thin film connected by resistive tunnel interfaces to thermal reservoirs having different chemical potentials and temperatures. The nonequilibrium longitudinal current-current correlation function is calculated within the nonlinear sigma model description and nonlinear dependence on temperatures and chemical potentials is obtained. Different contributions are calculated, originating from the fluctuation-induced suppression of the quasiparticle density of states, Maki- Thompson and Aslamazov-Larkin processes. As a special case of our results, close-to-equilibrium we obtain the longitudinal ac conductivity using the fluctuation-dissipation theorem

Order and Creep in Flux Lattices and CDWs Pinned by Planar Defects

The influence of randomly distributed point impurities \emph{and} planar defects on the order and transport in type-II superconductors and related systems is considered theoretically. For planar defects of identical orientation the flux line lattice exhibits a new glassy phase dominated by the planar defects with a finite compressibility, a transverse Meissner effect, large sample to sample fuctuations of the susceptibility and an exponential decay of translational long range order. The flux creep resistivity for currents $J$ parallel to the defects is $\rho(J)\sim \exp-(J_0/J)^{3/2}$ . Strong disorder enforces an array of dislocations to relax shear strain

Identification and classification of Serbia's historic floods

River flooding in Serbia is a natural phenomenon which largely exceeds the scope of water management and hydraulic engineering, and has considerable impact on the development of Serbian society. Today, the importance and value of areas threatened by floods are among the key considerations of sustainable development. As a result, flood protection techniques and procedures need to be continually refined and updated, following innovations in the fields of science and technology. Knowledge of high flows is key for sizing hydraulic structures and for gauging the cost-effectiveness and safety of the component structures of flood protection systems. However, sizing of hydraulic structures based on computed high flows does not ensure absolute safety; there is a residual flood risk and a risk of structural failure, if a flood exceeds computed levels. In hydrological practice, such floods are often referred to as historic/loads. The goal of this paper is to present a calculation procedure for the objective identification of historic floods, using long, multiple-year series of data on high flows of natural watercourses in Serbia. At its current stage of development, the calculation procedure is based on maximum annual discharges recorded at key monitoring stations of the Hydro-Meteorological Service of Serbia (HMS Serbia). When applied, the procedure results in the identification of specific historic maximum stages/floods (if any) at all gauge sites included in the analysis. The probabilistic theory is then applied to assess the statistical significance of each identified historic flood and to classify the historic flood, as appropriate. At the end of the paper, the results of the applied methodology are shown in tabular and graphic form for various Serbian rivers. All identified historic floods are ranked based on their probability of occurrence (i.e., return period)

Phase transition of interacting disordered bosons in one dimension

Interacting bosons generically form a superfluid state. In the presence of disorder it can get converted into a compressible Bose glass state. Here we study such transition in one dimension at moderate interaction using bosonization and renormalization group techniques. We derive the two-loop scaling equations and discuss the phase diagram. We find that the correlation functions at the transition are characterized by universal exponents in a finite region around the fixed point.Comment: five pages and two pages and one figur

Workplace stress of employees in public enforcement offices

Employees in Public Enforcement Offices are facing a great amount of workplace stress on a daily basis. Conflict situations regularly arise between public enforcement employees and other participants in the procedure: debtors, creditors and third parties, but also between the employees of other institutions- state bodies and organizations. Public enforcement officers, not only perform their functions with public authority, but at the same time, they are employers, and consequently obliged to take care of workplace health and safety of their employees. The techniques for stress reduction of employees, both during office and field work, are severely limited, but they are nevertheless possible and should be adequately employed and developed. In practice, the most frequent conflict situations between various participants are described and recommendations concerning specific measures are given with the purpose of stress reduction in employees

Assessment of hemostatic disturbances in women with established rheumatoid arthritis

Objectives This study was aimed to assess hemostatic disturbances in female patients with established rheumatoid arthritis (RA) in relation to menopausal status and disease activity. Method Ninety women were included in the study, 42 patients and 48 age-matched healthy controls. There were no differences between the investigated groups regarding the presence of traditional cardiovascular risk factors. Two global hemostatic assays were employed, namely endogenous thrombin potential (ETP) and overall hemostasis potential (OHP). The parameters of the ETP assay (ETP, C-max, t-lag, t-max) and OHP assay (overall coagulation potential (OCP) and overall fibrinolytic potential (OFP)) were assessed. Moreover, the parameters of the fibrin clot (lag time, Max Abs, and slope) were measured by clot turbidity and scanning electron microscopy (SEM). Both patients and controls were divided into four subgroups according to menopause status. Results The premenopausal controls differed significantly from all other subgroups in terms of diminished levels of ETP (p = 0.02), C-max (p = 0.01), OCP (p = 0.02), OHP (p = 0.001), and Max Abs (p = 0.008), while OFP (p = 0.0001) was increased. This tendency was not seen in the premenopausal RA patients compared with the postmenopausal RA patients. SEM images showed denser clots composed of thinner fibers in samples from RA patients. The disease activity measured by DAS28 correlated with OCP and OHP (r = 0.54; p = 0.001 and r = 0.44; p = 0.003, respectively) indicating persistent hypercoagulable condition in the whole group of RA patients. Conclusions Our results point towards coagulation activation in premenopausal women with established RA. The patients were well characterized, which enabled assessment in a real-life setting

Digitalne veštine kao uslov za uspešnu primenu inovacija u turizmu - šansa ili ograničenje za Srbiju

Proces digitalne transformacije ubrzan je tokom pandemije Covid-19, što je karakteristično za većinu sektora, a posebno za turistički sektor koji predstavlja lidera u primeni digitalnih inovacija u poslovanju. Republika Srbija prepoznala je značaj turizma, ali i digitalnih inovacija u ovom sektoru i predvidela brojne mere i inicijative u javnim politikama. Međutim, postavlja pitanje da li nivo digitalnih veština stanovništva predstavlja šansu ili ograničenje za njihovu realizaciju. Istraživanje u ovom poglavlju ukazuje da nivo digitalnih veština stanovnika Srbije nije podržavajući, već ograničavajući faktor za uspešnu primenu mera koje podrazumevaju implementaciju digitalnih rešenja