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D. Mihailović, E. Nikolić-Djorić, N. Drešković, G. Mimić

We have used the Kolmogorov complexities, sample and permutation entropies to quantify the randomness degree in river flow time series of two mountain rivers in Bosnia and Herzegovina, representing the turbulent environmental fluid, for the period 1926–1990. In particular, we have examined the monthly river flow time series from two rivers (the Miljacka and the Bosnia) in the mountain part of their flow and then calculated the Kolmogorov complexity (KL) based on the Lempel–Ziv Algorithm (LZA) (lower—KLL and upper—KLU), sample entropy (SE) and permutation entropy (PE) values for each time series. The results indicate that the KLL, KLU, SE and PE values in two rivers are close to each other regardless of the amplitude differences in their monthly flow rates. We have illustrated the changes in mountain river flow complexity by experiments using (i) the data set for the Bosnia River and (ii) anticipated human activities and projected climate changes. We have explored the sensitivity of considered measures in dependence on the length of time series. In addition, we have divided the period 1926–1990 into three subintervals: (a) 1926–1945, (b) 1946–1965, (c) 1966–1990, and calculated the KLL, KLU, SE, PE values for the various time series in these subintervals. It is found that during the period 1946–1965, there is a decrease in their complexities, and corresponding changes in the SE and PE, in comparison to the period 1926–1990. This complexity loss may be primarily attributed to (i) human interventions, after the Second World War, on these two rivers because of their use for water consumption and (ii) climate change in recent times.

L. Smajlović, J. Jorgenson, H. Then

In this paper we study, both analytically and numerically, questions involving the distribution of eigenvalues of Maass forms on the moonshine groups $\Gamma_0(N)^+$, where $N>1$ is a square-free integer. After we prove that $\Gamma_0(N)^+$ has one cusp, we compute the constant term of the associated non-holomorphic Eisenstein series. We then derive an "average" Weyl's law for the distribution of eigenvalues of Maass forms, from which we prove the "classical" Weyl's law as a special case. The groups corresponding to $N=5$ and $N=6$ have the same signature; however, our analysis shows that, asymptotically, there are infinitely more cusp forms for $\Gamma_0(5)^+$ than for $\Gamma_0(6)^+$. We view this result as being consistent with the Phillips-Sarnak philosophy since we have shown, unconditionally, the existence of two groups which have different Weyl's laws. In addition, we employ Hejhal's algorithm, together with recently developed refinements from [31], and numerically determine the first $3557$ of $\Gamma_0(5)^+$ and the first $12474$ eigenvalues of $\Gamma_0(6)^+$. With this information, we empirically verify some conjectured distributional properties of the eigenvalues.

J. Sedlar, D. Vukičević, F. Cataldo, O. Ori, A. Graovac

In this paper, we establish leading coefficient of Wiener index for open and closed 2-dimensional rectangular lattices, for various open and closed polygonal lattices, and for open and closed multidimensional cubes. These results enable us to establish compression ratio of Wiener index when number of rows and columns in the lattice tends to infinity.

L. Pecchia, Jennifer L. Martin, Angela Ragozzino, Carmela Vanzanella, Arturo Scognamiglio, L. Mirarchi, S. P. Morgan

BackgroundThe rigorous elicitation of user needs is a crucial step for both medical device design and purchasing. However, user needs elicitation is often based on qualitative methods whose findings can be difficult to integrate into medical decision-making. This paper describes the application of AHP to elicit user needs for a new CT scanner for use in a public hospital.MethodsAHP was used to design a hierarchy of 12 needs for a new CT scanner, grouped into 4 homogenous categories, and to prepare a paper questionnaire to investigate the relative priorities of these. The questionnaire was completed by 5 senior clinicians working in a variety of clinical specialisations and departments in the same Italian public hospital.ResultsAlthough safety and performance were considered the most important issues, user needs changed according to clinical scenario. For elective surgery, the five most important needs were: spatial resolution, processing software, radiation dose, patient monitoring, and contrast medium. For emergency, the top five most important needs were: patient monitoring, radiation dose, contrast medium control, speed run, spatial resolution.ConclusionsAHP effectively supported user need elicitation, helping to develop an analytic and intelligible framework of decision-making. User needs varied according to working scenario (elective versus emergency medicine) more than clinical specialization. This method should be considered by practitioners involved in decisions about new medical technology, whether that be during device design or before deciding whether to allocate budgets for new medical devices according to clinical functions or according to hospital department.

Ibrahim Gledo, N. Pranjić, K. Drljević, S. Prasko, I. Drljević, P. Brzeziński

Aim of the study Exposure to radiation and aging are the leading causes of breast cancer among female patients. We aimed to investigate and assess the relationship between exposure to medical, diagnostic and iatrogenic radiation and breast cancer using a questionnaire among 100 newly diagnosed female breast cancer patients and 100 control female subjects without cancer. Material and methods A case control study using a family ambulatory based survey was conducted among 200 female patients from all municipalities of Zenica-Doboj Canton. New cases of breast cancer among subjects of experimental groups (n = 100) were diagnosed between 1 January 2003 and 31 December 2007 using the institutional clinical procedure for breast cancer diagnosis. Data were obtained using a self-rated questionnaire on radiation as a breast carcinogen. Data analysis was performed using SPSS version 19.0. Results There were no significant differences between the two groups and their subgroups for individual data and demographics except for prevalence of decreased family financial situation (practical poverty) among subjects with breast cancer in relation to control subjects (31%: 17% among control subjects; p = 0.001). Female patients who are exposed to iatrogenic radiation before the 3rd year of life (OR = 1.29; 95% CI: 0.839–1.985) and those who are exposed to CT more than twice per year are more than twice as likely to have breast carcinoma (OR = 2.02; 95% CI: 1.254–3.261) compared to control subjects. Poverty and low family income are vulnerability factors associated with elevated levels of breast carcinoma. This result is not in accordance with prior study results. ConcIusions It is necessary to develop an adequate registration system of iatrogenic exposure to radiation for each patient of any age, particularly for children aged < 3 years and for CT iatrogenic exposure.

Matheus Araújo, N. Araújo, M. D. Cunha, Marcelo Nogueira de Souza, Antônio Carneiro

Introducao: O tumor de celulas granulares e uma neoplasia benigna rara que pode ocorrer em qualquer parte do corpo. Na mama, representa 5-6% de todos os tumores de celulas da granulares. Geralmente sao nodulos que podem simular um carcinoma invasivo em exames de imagem. Histologicamente e caracterizado por uma proliferacao de celulas poligonais de aspecto granular que se agrupam em ninhos, cordoes ou lencois e apresentam uma forte marcacao imuno-histoquimica para a proteina S-100. A doenca de Castleman e um disturbio linfoproliferativo benigno rarode origem controverso, caracterizada pela proliferacao de tecido linfoide em qualquer cadeia linfatica. Clinicamente,essa doenca e dividida em forma unicentrica e multicentrica, a cura na forma unicentrica e possivel por meio daexcisao cirurgica, enquanto a forma multicentrica tem um prognostico mais reservado em longo prazo. Relato docaso: Descreveu-se o caso de uma paciente com um nodulo de mama sugestivo de carcinoma e que teve o diagnostico de tumor de celulas da granulares e, em exames de estadiamento, foi encontrada uma massa em retroperitonio que,apos resseccao cirurgica, foi diagnosticada como doenca de Castleman. Conclusao: Deve-se ter, como diagnostico diferencial de tumores malignos de mama, o tumor de celulas granulares, devido a similaridade ao exame clinico e em exames de imagem. A doenca de Castleman deve estar no diagnostico diferencial de massas retroperitoneais.

E. Kučukalić-Selimović, J. Alagić, A. Valjevac, Almira Hadžović-Džuvo, A. Begić, N. Bešlić

Serum thyreoglobulin (Tg) and whole body scintigraphy (I-131 WBS) have been used to detect recurrent and metastatic thyroid cancers postoperatively. However, discordant results of Tg measurement and 131I WBS have been reported. Negative 131I WBS and a positive Tg test are usually found, but less common occurrence of positive 131I WBS and a negative Tg test has also been demonstrated in a small but significant number of cases. Therefore, the aim of the study was to retrospectively analyse patients with positive 131I WBS after total thyreoidectomy and again 1 year after the radioactive iodine. There were 52 patients included in the study. Four weeks after surgery, during which thyroid hormone treatment was not introduced, each patient received an ablative dose of 131I. The evaluation of the WBS was qualitative and considered positive if thyroid remnant, lymphatic node or metastasis were detected. WBS and serum Tg was measured 12 months after 131I ablation with thyroid hormone suppression. We considered positive any Tg level above the sensitivity values and negative if lower than this level. Tg levels were related to the existence of a positive scan or a negative one. In our 52 WBS positive patients concordant positive Tg levels were observed in 42 patients while in 10 patients we found a negative Tg levels after the surgery. After 1-year follow-up, out of initially 42 concordant patients 8 patients showed remaining concordant positive Tg and WBS values. Discordant results were observed in 13 patients (4 patients were Tg- and WBS+ while 9 patients were Tg+ and WBS-). In the majority of patients (50%) remained with concordant results but changed from Tg+ and WBS+ to Tg- and WBS-. Diagnostic WBS is an additional valuable tool, besides Tg levels, in the follow up of patients after total thyreoidectomy.

Analog network coding (ANC) as a simple implementation of physical layer network coding based on orthogonal frequency division multiplexing (OFDM) has been proposed to increase the network capacity and reliability of bi-directional link between a pair of users. In ANC protocol, an information between a pair of users is exchanged through two orthogonal time phases (i.e., multiple-access and broadcast phases). On the other hand, the phase noise (PN) introduces phase offset and inter carrier interference (ICI) to the useful signal. Thus, in ANC scheme PN will affect the useful signal during both multiple-access and broadcast phases. In this article, we present a performance analysis of ANC scheme using OFDM in the presence of PN in frequency-selective fading channel. We derive the total composite variance of ANC scheme in the presence of PN to obtain the signal-to-interference-plus-noise ratio (SINR) expression. Then, we evaluate the system’s performance in terms of bit error rate (BER), SINR degradation, and ergodic capacity through both numerical and computer simulations. Computer simulated average BER has been consistent with the numerical results, validating the presented analysis. Our results have shown that the ANC scheme is more sensitive to the PN introduced during the broadcast phase (i.e., at destination) than during the multiple-access phase (i.e., at relay). This is because of the higher ICI to the useful signal and enhanced noise due to the imperfect self-information removal at the destination. In addition, the performance degradation of ANC scheme based on OFDM in the presence of PN is highly expressed for the PN linewidth values up to 20 Hz.

K. Wiege, S. R. Ali, Britta Gewecke, A. Novakovic, F. Konrad, Katja Pexa, S. Beer-Hammer, J. Reutershan et al.

Nikolina Dukić, Andrea Arbula Blecich, Ljerka Cerović

Abstract The main goal of this paper is to elaborate the importance of health literacy in cost-effective utilization of health care services which influence the efficiency of the entire health care sector. In order to complement the theoretical framework of the economic implications and the circular influence of health literacy on the economy, an empirical analysis was carried out using S–TOFHLA. The results suggest that the patients’ personal characteristics and the accessibility to health care services influence the level of health literacy which affects the health care costs.

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