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Introduction/Objective. During hemodialysis (HD) treatment great fluctuations were recorded in the systemic hemodynamic parameters and in the volume and composition of ocular fluid. There are only a few studies that analyzed the effect of HD on retinal and macular thickness with conflicting results. Objective of this study was to determine macular thickness, marked as central foveal thickness, average macular thickness and macular volume, shortly before and after HD. Methods. This prospective study included 30 chronic renal failure (CRF) patients of HD treatment. Thorough ophthalmologic examinations were performed including evaluation of best corrected visual acuity, intraocular pressure and slit-lamp examination of all eye segments. Macular thickness was determined by optical coherence tomography shortly before and after HD. The next parameters were evaluated: central foveal thickness, average macular thickness and macular volume. The correlation between systemic parameters and macular thickness changes during HD was tested. Results. There were significant changes in body weight and blood pressure pre- and post-HD. Results showed macular thickness (central foveal thickness, average macular thickness and macular volume) decreased, but the change was not significant. There was no significant correlation between systemic hemodynamic parameters and macular thickness changes. Conclusion. Results of this study showed there was no statistically significant changes in macular thickness CRF patient undergoing HD. Further research on a larger group of patients and a longer follow-up time are required to confirm these findings.

Recently, as the structural design has shifted to the performance design, seismic design of tunnel structures considering soil-structure interaction becomes more important. The effects of soil-structure interaction should not be overlooked for the reason that the interaction effects between a structure and surrounding ground may cause larger external forces to the structure. It has been highlighted that the relative rigidity between the soil and the structure is the predominant factor influencing the soil-structure interaction effects. With an aim to study the effects of tunnel-ground interaction, a number of analyses were carried out in this work, based on the most frequently used analytical expressions for evaluation of seismically induced stress increment in a tunnel lining accounting for the soil-structure interaction effects. These solutions are functions of the shear strain field which is the cause of the ovaling of the circular tunnel cross-section. A value of the average soil shear strain in the range of depths corresponding to the tunnel section, between the tunnel crown and the invert, has been computed through a free-field one-dimensional seismic site response analysis preformed by the code EERA. Various levels of analysis have been undertaken on different soil conditions, considering representative of two main soil classes - stiff soil of good conditions and soft saturated soil of poor conditions, as well as, two extreme cases of tunnel-ground interface - the full-slip and the no-slip conditions. Finally, the results for all the considered cases have been evaluated and compared, and the significant mutual differences with regard to a tunnel-ground interaction have been underlined.

Different spice oleoresins are widely used in meat industry. They contribute to the specific aroma and flavor of the end products, but they have also been reported to have strong antimicrobial activity. These properties open a plenty of possibilities to be used for defining the specific sensory profile of the product but also as natural food preservatives. This paper focuses on the antifungal activity of four oleoresins against different foodborne toxigenic Aspergillus species. Oleoresins used in the experiments were cayenne pepper, black pepper, garlic and rosemary oleoresins, and they were tested against following Aspergillus species: A. clavatus, A. flavus, A. fumigatus, A. niger, A. ochraceus and A. versicolor. Antifungal activity was tested using microtitre-plate-based assay incorporating resazurin as an indicator of cell growth and broth microdilution-method. [Projekat Ministarstva nauke Republike Srbije, br. III46009]

Unlike the other eurocodes where structure designing is fairly clear, there are three design approaches offered in Eurocode 7 and sets of applied partial factors. After accepting Eurocode 7, each country has to decide on two very important decisions related to the selection of appropriate design approach according to which designing of geotechnical structures is going to be performed and define adequate partial factors. Selection of appropriate design approach is based on analyses of certain geotechnical problem both with actual and proposed methods. Therefore, it should be find out which approach is the closest to hitherto calculation 'style', which compatibility of 'old' and new method will serve as a base for selecting appropriate design approach. Moreover, it will be tested with different partial factors in order to obtain approximately the same size of structural elements or construction, which similarity will suggest the value of partial factors. Analyses and verifications are performed for such purposes for retaining walls, which conclusions, presented below, lead to solution that can be used in the region.

In this paper, the possibility of determining the thermal, elastic and geometric characteristics of a thin TiO2 film deposited on a silicon substrate, with a thickness of 30 μm, in the frequency range of 20 to 20 kHz with neural networks were analysed. For this purpose, the geometric (thickness), thermal (thermal diffusivity, coefficient of linear expansion) and electronic parameters of substrates were known and constant in the two-layer model, while the following nano-layer thin-film parameters were changed: thickness, expansion and thermal diffusivity. Predictions of these three parameters of the thin-film were analysed separately with three neural networks. All of them together were joined by a fourth neural network. It was shown that the neural network, which analysed all three parameters at the same time, achieved the highest accuracy, so the use of networks that provide predictions for only one parameter is less reliable. The obtained results showed that the application of neural networks in determining the thermoelastic properties of a thin film on a supporting substrate enables the estimation of its characteristics with great accuracy. [ABSTRACT FROM AUTHOR]

The determination of stress states around cavities in the stressed elastic body, regardless of cavity shapes, that may be spherical, cylindrical elliptical etc. in its analytical approach has to be based on selection of a stress function that will satisfy biharmonic equation, under given boundary conditions. This paper is concerned with formulation and solution of the cited differential equation using elliptical coordinates in conformity with the cavity shape of oblong ellipsoid [1]. It is therefore considered that the formulation of the stress tensor will be done in conformity to the cited coordinates. The paper describes basic statements and definitions in connection to harmonic functions used for determination of stress states around cavities formed in the stressed homogeneous space. The particular attention has been paid to the use of Legendre`s functions, with definitions and derivation of recurrent formulas, that have been used for determination of stress states around an oblong ellipsoidal cavity, [1]. The paper also includes the description of procedures used in forming series based on Legendre`s functions of the first order.

Investigation of the stress field around the cavity that is loaded or partially loaded at the inner surface by the rotationally symmetric loading is still the contemporary problem in the theory of elasticity. As the contribution to the similar investigations, the paper introduces the new function of loading in the form of the infinite sine series. Besides the definition of the mentioned loading function as the boundary condition on inner surface of the cavity, the paper presents the comparative analysis of the new function with the previously used ones. The said loading function at the inner surface of a cavity is internal loading between rock mass and supporting structure, for the case of homogeneous isotropic elastic medium as the first approximation of the real situation.

The total electron impact ionization cross sections of the acetylene molecule have been measured in the incident electron energy range from threshold to 1000 eV. These results are compared with other existing data, obtained by direct measurements of this molecular property or by indirect ones, via the partial ionization cross sections for the formation of different ions. Using three semiempirical equations, the total ionization cross sections were calculated and compared to available data, too. Direct and dissociative ionization cross sections were also calculated by a semiempirical equation and compared to existing data.

Contemporary life streams, more often than ever, impose the necessity for construction of new underground structures in the vicinity of existing tunnels, with an aim to accommodate transportation systems and utility networks. A previously uninvestigated case, in which a newly-constructed tunnel opening is closely positioned behind an existing tunnel, referred to as the tunnel--cavity configuration, has been considered in this study. An exact analytical solution is derived considering a pair of parallel circular cylindrical structures of infinite length, with the horizontal alignment, embedded in a boundless homogeneous, isotropic, elastic medium and excited by timeharmonic plane SV-waves under the plane-strain conditions. The Helmholtz decomposition theorem, the wave functions expansion method, the translational addition theorem for bi-cylindrical coordinates, and the pertinent boundary conditions are jointly employed in order to develop a closed-form solution of the corresponding boundary value problem. The primary goal of the present study is to examine the increase in dynamic stresses at an existing tunnel structure due to the presence of a closely driven unlined cavity, as well as in a localized region around the tunnel (at the position of the cavity in close proximity), under incident SV-waves. A new quantity called dynamic stress alteration factor is introduced and the aspect of the minimum seismically safe distance between the two structures is particularly considered. [ABSTRACT FROM AUTHOR]