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Meliha Povlakić Hadžiefendić, Esad H. Mahmutović, Husnija Hasanbegović

The aim of the paper was to determine the perception of parental support and understanding by deaf and hard-of-hearing students. The sample consisted of 47 deaf and hard-of-hearing students, both genders, with an average age of 16 ± 1.27 years. Children's Perceptions of Parents Scale, (Grolnick, Ryan & Deci, 1991), which consists of three subscales, and which measure parental involvement, support of autonomy and parental warmth, especially for the mother, especially for the father was used in this research. The data were processed by descriptive analysis, and the t-test was used to test the mother's support perception difference in relation to father’s support perception. The results showed that deaf and hard-of-hearing students mostly positively perceived the parent involvement, support of autonomy and warmth of both parents, but a statistically significant difference in the individual perception of parents was found in favor of the mothers.

Augustine Ikpehai, B. Adebisi, Khaled Maaiuf Rabie, K. Anoh, Ruth Ande, Mohammad Hammoudeh, H. Gačanin, U. Mbanaso

The rapid growth of Internet-of-Things (IoT) in the current decade has led to the development of a multitude of new access technologies targeted at low-power, wide area networks (LP-WANs). However, this has also created another challenge pertaining to technology selection. This paper reviews the performance of LP-WAN technologies for IoT, including design choices and their implications. We consider Sigfox, LoRaWAN, WavIoT, random phase multiple access (RPMA), narrowband IoT (NB-IoT), as well as LTE-M and assess their performance in terms of signal propagation, coverage and energy conservation. The comparative analyses presented in this paper are based on available data sheets and simulation results. A sensitivity analysis is also conducted to evaluate network performance in response to variations in system design parameters. Results show that each of RPMA, NB-IoT, and LTE-M incurs at least 9 dB additional path loss relative to Sigfox and LoRaWAN. This paper further reveals that with a 10% improvement in receiver sensitivity, NB-IoT 882 MHz and LoRaWAN can increase coverage by up to 398% and 142%, respectively, without adverse effects on the energy requirements. Finally, extreme weather conditions can significantly reduce the active network life of LP-WANs. In particular, the results indicate that operating an IoT device in a temperature of −20 °C can shorten its life by about half; 53% (WavIoT, LoRaWAN, Sigfox, NB-IoT, and RPMA) and 48% in LTE-M compared with environmental temperature of 40 °C.

K. Anoh, Augustine Ikpehai, B. Adebisi, Khaled Maaiuf Rabie, W. Popoola, H. Gačanin

Orthogonal frequency-division multiplexing (OFDM) is a popular multi-carrier technique used in many digital communication systems such as wireless fidelity (Wi-Fi), long term evolution (LTE) and power line communication systems. It can be designed using fast Fourier transform (FFT) or wavelet transform (WT). The major drawback in using WT is that it is computationally inefficient. In this study, we introduce a simple and computationally efficient WT, harmonic wavelet transform, for OFDM signal processing. The new WT uses the orthogonal basis functions of conventional FFT-OFDM except that it involves translation and dilation of the input signal; the new wavelets is referred to as harmonic wavelets (HW). When compared with pilot-assisted OFDM system in terms of reduction in the peak-to-average power ratio, the results show that HW-OFDM outperforms FFT-OFDM by 3 dB at 10−4 CCDF (complementary cumulative distribution function). Over Rayleigh fading channel with additive white Gaussian noise (AWGN), the bit error ratio of both FFT-OFDM and HW-OFDM perfectly matched, showing that the proposed HW-OFDM is better in terms of peak-to-average power ratio reduction.

Sibren De Bast, R. T. Duran, A. Chiumento, S. Pollin, H. Gačanin

Network slicing, a key enabler for future wireless networks, divides a physical network into multiple logical networks that can be dynamically created and configured. In current IEEE 802.11 (Wi-Fi) networks, the only form of network configuration is a rule-based optimization of few parameters. Future access points (APs) are expected to have self-organizational capabilities, able to deal with large configuration spaces in order to dynamically configure each slice. Deep Reinforcement Learning (DRL) can achieve promising results in highly dynamic and complex environments without the need for an operating model, by learning the optimal strategy after interacting with the environment. However, since the number of possible slice configurations is huge, achieving the optimal strategy requires an exhaustive learning period that might yield an outdated slice configuration. In this paper, we propose a fast-learning DRL model that can dynamically optimize the slice configuration of unplanned Wi-Fi networks without expert knowledge. Enhanced with an off-line learning step, the proposed approach is able to achieve the optimal slice configuration with a fast convergence, which is attractive for dynamic scenarios.

Introduction: Renal vasculature is extremely sensitive to vasoconstrictor effects of endothelin (ET), while nitric oxide (NO) has special role in several pathological renal conditions. Aim: The aim of this study to examine the presence, character, and degree of changes in NO and ET levels in the serum of extracorporeal shock wave lithotripsy (ESWL)-treated patients with nephrolithiasis. Patients and Methods: This study included a total of 60 patients that were divided in two groups: Group I (n = 24), in which a total of 2000SWs were administered; 0–2 units; (0.5 units per each 500SWs), and Group II (n = 36), in which a total of 4000SWs were administered; 0–4 units; (0.5 units per each 500SWs). Results: In the Group I median NO serum concentration increased in relation to pretreatment levels (39.04 ± 8.29 μmol/L) specifically 30 min, 60 min, and 24 h following the treatment (39.11 ± 12.60), (41.80 ± 6.89), and (46.33 ± 9.03), where concentration growth after 24 h was statistically significant P < 0.01. The NO serum concentration in the Group II increased in relation to pretreatment levels (38.90 ± 10.33 μmol/L) after 30 min (48.71 ± 30.09), 60 min (54.57 ± 39.76), and 24 h (97.95 ± 72.07). The NO concentration increase after 60 min and 24 h is statistically significant, respectively, P < 0.03 and P < 0.0001. Conclusion : NO and ET serum levels are changing under the influence of ESWL, and that the NO and ET changes are directly correlated with the number of administered shock waves and administered energy.

A. Gazibegović-Busuladžić, M. Busuladžić, A. Čerkić, E. Hasović, W. Becker, D. Milošević

We investigate strong-field ionization of linear molecules by a two-color laser field of frequencies rω and sω having coplanar counterrotating or corotating elliptically polarized components (ω is the fundamental laser field frequency and r and s are integers). Using the improved molecular strong-field approximation we analyze direct above-threshold ionization (ATI) and high-order ATI (HATI) spectra. More precisely, reflection and rotational symmetries of these spectra for linear molecules aligned in the laser-field polarization plane are considered. The reflection symmetries for particular molecular orientations, known to be valid for a bicircular field (this is the field with circularly polarized counterrotating components), are valid also for arbitrary component ellipticities. However, specific rotational symmetries that are satisfied for HATI by a bicircular field, are violated for an arbitrary elliptically polarized field with counterrotating components. For the corotating case and the N2 molecule we analyze molecular-orientation-dependent interferences and plateau structures for various ellipticities.

High-order harmonics generated by a linearly polarized laser field are also linearly polarized. Having in mind that for various application, such as the exploration of magnetic materials, chiral molecules etc., we need circularly polarized high harmonics which serve as coherent soft x-rays, we explore high-order harmonic generation by the so-called bicircular laser field. This field consists of two coplanar counter-rotating circularly polarized fields of different frequencies equal to integer multiples of a fundamental frequency ω. High harmonics generated by such field are circularly polarized with helicity alternating between +1 and −1. Combining a group of such harmonics, instead of obtaining a circularly polarized attosecond pulse train, one obtains a pulse with unusual polarization properties. But, if the harmonics of particular helicity are stronger, i.e., if we have helicity asymmetry in a high-harmonic energy interval, then it is possible to generate an elliptical or even circular pulse train. We theoretically investigated a wide range of bicircular field-component intensities (I1 and I2) and found regions where both the harmonic intensity is high and the helicity asymmetry is large. Particular attention is devoted to the ω−2ω and ω−3ω bicircular fields and atoms having the s and p ground states. In our calculations we use strong-field approximation and quantum-orbit theory. We show that, even in the extreme case of I2 = 8I1, for an ω−3ω bicircular field, high-order harmonic generation is more efficient than in the I2 = I1 case. The obtained results are explained analyzing the relevant electron trajectories and velocities, which follow from the quantum-orbit theory. For the atoms having p ground state the helicity asymmetry parameter is large for a wide range of high-harmonic photon energies, while for the atoms having s ground state the helicity asymmetry parameter can be large only for low harmonics. We confirm this by averaging the obtained results over the intensity distribution in the laser focus.

N. Todorović, A. Jović-Vraneš, B. Djikanović, Nataša Pilipović-Broćeta, N. Vasiljevic, M. Račić

Health literacy (HL) has become an important area of research. The aim of this study was to evaluate the HL of primary healthcare patients in the Republic of Srpska (RS), Bosnia and Herzegovina (B&H) and to identify socioeconomic and health factors associated with HL. This cross-sectional study among 768 patients was conducted in two healthcare centres between March and May 2017, using the Short Test of Functional Health Literacy in Adults (S-TOFHLA). Analysis was done using descriptive and inferential statistics (a chi-squared test and logistic regression). Inadequate and marginal HL was found in 34,6% of respondents. Socioeconomic and self-reported health factors were significantly related to HL. An age of 55 years and over (OR 1.02), living in a rural environment (OR 2.25), being divorced (OR 3.32), being insufficiently physically active (OR 1.29), having poor income (OR 1.96), having more than three chronic diseases (OR 1.94), and poor health (OR 1.59) were significantly corelated with inadequate and marginal HL. The results of our study indicate that a low level of HL is related to the elderly, having a divorce, having a rural residence, poor income, having more than three chronic diseases, poor health, and insufficient physical activity. Further evaluation, monitoring, and activities to improve HL are of great importance for patients’ health outcomes.

Irena Palić, S. Hodžić, Ksenija Dumičić

Abstract Background: In recent years’ income inequality has been an economic issue. The primary instrument for redistributing income is personal income tax. However, based on economic theory income inequality concerns indicators such as wages, transfer payments, taxes, social security contributions, and geographical mobility. Objectives: The objective of this paper is to examine the impact of certain labor market indicators on personal income taxation in Federation of Bosnia and Herzegovina (FB&H). Methods/Approach: Since personal income taxation consists of a very broad definition and for the purpose of this research only, income from dependent (employment) activity is observed. The econometric analysis is conducted using error correction modeling, as well as forecast errors variance decomposition. Results: The error correction model is estimated, and the cointegrating equation indicates that monthly wage and number of employees statistically significantly positively affect personal income taxes in FB&H in the long-run. After two years, the selected labor market indicators explain a considerable part of forecasting error variance of personal income tax revenues. Conclusions: The implementation of reforms in the labor market and tax policies of the FB&H is suggested. In order to achieve necessary reforms, efficient governance and general stable political environment are required.

Amel Durakovic, P. Hunt, S. Patil, S. Sarkar

Reconstructions of the primordial power spectrum (PPS) of curvature perturbations from cosmic microwave background anisotropies and large-scale structure data suggest that the usually assumed power-law PPS has localised features (up to \sim 10\%∼10% in amplitude), although of only marginal significance in the framework of \LambdaΛCDM cosmology. On the other hand if the cosmology is taken to be Einstein-de Sitter, larger features in the PPS (up to \sim 20\%∼20% in amplitude) are required to accurately fit the observed acoustic peaks. Within the context of single clock inflation, we show that any given reconstruction of the PPS can be mapped on to functional parameters of the underlying effective theory of the adiabatic mode within a 2nd-order formalism, provided the best fit fractional change of the PPS, \Delta{P}_{R}/{P}_{R}ΔPR/PR is such that (\Delta{P}_{R}/{P}_{R})^3(ΔPR/PR)3 falls within the 1\,\sigma1σ confidence interval of the reconstruction for features induced by variations of either the sound speed c_\mathrm{s}cs or the slow-roll parameter \epsilonϵ. Although there is a degeneracy amongst these functional parameters (and the models that project onto them), we can identify simple representative inflationary models that yield such features in the PPS. Thus we provide a dictionary (more accurately, a thesaurus) to go from observational data, via the reconstructed PPS, to models that reproduce them to per cent level precision.

F. Zvizdić, E. Begić, A. Mujaković, E. Hodžić, B. Prnjavorac, Omer Bedak, F. Čustović, Haris Bradaric et al.

Introduction: The most appropriate choice of pharmacological treatment of heart rhythm disorders occurring in patients with chronic obstructive pulmonary disease (COPD) and cardiovascular comorbidity is often a topic of debate between pulmonologists and cardiologists in clinical practice, although numerous studies and clinical trials have demonstrated evidence to support the use of selective beta-blockers (BBs) in these patients. Aim: To examine the difference in the number of exacerbations in patients treated with a combination of verapamil and digoxin or BB alone in patients with different COPD stages. Patients and methods: The study included 68 patients (n = 68) diagnosed with COPD who were followed-up during a 12-month period, and the number of exacerbations were analyzed. The patients were divided into two groups according to the stage of COPD: GOLD II (moderate), and GOLD III (severe), and in each group a subdivision was established in relation to the use of either a combination of verapamil and digoxin or the use of BBs alone in pharmacological treatment. The inclusion criteria for patients were defined as following: a) established diagnosis of COPD according to present or deteriorated relevant clinical symptoms and signs, b) the ejection fraction (EF) of a left ventricle (LV) >35%, and c) spirometric cut-points classified as GOLD II (FEV1 / FVC <0.7, FEV1 predicted 50-80%), or GOLD III (FEV1/FVC <0.7, FEV1 predicted 30-50%) stage of the COPD. The exclusion criteria were EF of LV <35% and a lethal outcome during a follow-up period (2 patients were encountered). Exacerbation was defined as functional deterioration of the COPD symptoms verified by spirometric functional testing, frequency of hospitalizations according to GOLD stage assignment or verified clinical symptoms deterioration. Results: Regardless the pharmacological treatment, there is a statistically significant increase in the number of COPD exacerbations, in a 12-month period follow-up, in the GOLD III group (severe) compared to the GOLD II group (moderate). In the group of patients taking verapamil and digoxin, a two-tailed t-test was used to analyze the results between the GOLD II and GOLD III stage groups, p = 0.01, and 2. In the group of patients taking BBs, a two-tailed t-test was also used to analyze the results between the GOLD II and GOLD III stage groups, p = 0.003). Within the COPD GOLD II stage group, there appears to be no statistically significant difference in the number of exacerbations between the patients taking verapamil and digoxin (n = 24) and the patients taking BBs alone (n = 15), although, in patients taking BBs alone, there appears to be a trend towards a decrease in the exacerbations compared to the number of exacerbations in patients taking verapamil and digoxin (p = 0.007). Within the COPD GOLD III stage group, there is no difference in the number of exacerbations between the patients taking verapamil and digoxin (n = 20), and the patients taking BBs alone (n = 9), as analyzed by a two-tailed t-test, p = 0.577. Conclusion: Use of selective BBs in the treatment of cardiovascular comorbidity in patients with COPD represents a far better choice of pharmacological approach in the treatment of patients diagnosed with COPD GOLD II (moderate) stage.

Edin Muftić, Adela Jahić, R. Kovačević

The aim of the research is to determine the characteristics of the prosocial behavior of primary and high school students in terms of the structure of leisure time. The sample of respondents consists of 230 students of the final grades of primary and high schools, both genders, aged 14-19. The research was conducted in the area of Tuzla during the school year 2017/2018. years. The survey used the measuring instrument "Scale of self-assessment of juvenility behavior YSR". Mann Whitney U test was used for statistical analysis of data. When analyzing the prosocial behavior of primary and high school students in terms of the structure of leisure time, statistically significant differences at the level of p≤0,05 were established in such a way that students with structured leisure time compared to students whose leisure time is not structured more often : are fairly honest, they do things better than most children, they can be pretty friendly, they are skillful with their hands, they fight for their rights, enjoy being with other people, they like to make others laugh, they like to help others.

R. Joshi, B. Knapmeyer‐Endrun, K. Mosegaard, F. Bissig, Amir Khan, M. Panning, S. Staehler, B. Tauzin et al.

(1) Max-Planck Institute for Solar System Science, Planets and Comets, Göttingen, Germany (joshir@mps.mpg.de), (2) Institute of Geology and Mineralogy, University of Cologne, Cologne, Germany (brigitte.knapmeyer-endrun@uni-koeln.de), (3) Institute of Geophysics, ETH Zürich, Switzerland (vandriel@erdw.ethz.ch), (4) Institute of Geophysics, ETH Zürich, Switzerland (savas.ceylan@erdw.ethz.ch), (5) Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA (mark.p.panning@jpl.nasa.gov)

Mario Kordić, Davor Tomić, Dragutin Soldo, D. Hauptman, D. Ježek

Aim To analyze the differences in the population of perivascular and peritubular Leydig cells (LC) and the number of Reinke's crystals (RCs) in the testicles of infertile men with non-obstructive and obstructive azoospermia. Methods This retrospective case-control study was conducted on the testicle tissue of infertile men with obstructive (n = 10) and those with non-obstructive azoospermia (n = 100). Stereological analysis was performed on 7-μm paraffin sections. Measurements were carried out by using the Weibel multipurpose test system. Results Patients with non-obstructive azoospermia had a higher total/absolute number of LCs in the perivascular space (P = 0.034). In these patients, no significant difference was found in the total and absolute number of RCs between the peritubular and perivascular space. Patients with obstructive azoospermia had around three times higher absolute number of RCs in both the peritubular and perivascular spaces (P = 0.002; P < 0.001) than non-obstructive group. Conclusion Our results suggest that in patients with non-obstructive azoospermia LCs migrated or had different densities in the peritubular and perivascular space compared with patients with obstructive azoospermia. Moreover, the lower number of RCs could imply their utilization by LCs in testosterone production.

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