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The aim of this study was to compare vestibular evoked myogenic potentials (VEMP) and video head impulse test (vHIT) results in patients presenting with vertigo and dizziness. We retrospectively analyzed data of all patients with the chief complaint of vertigo, dizziness, or imbalance that underwent VEMP and vHIT from January 2015 to January 2016. A total of 117 patients (73 females, mean age 53.92 ± 16.76) fulfilled inclusion criteria: group 1 included patients with the final diagnosis of vestibular neuritis (VN) ( N = 31 (16 right and 15 left VN)), group 2 included patients with the final diagnosis of vertigo of central origin ( N = 23) and group 3 included patients with the final diagnosis of unspecified dizziness ( N = 63). There was significant correlation between oVEMP asymmetry and asymmetry of the lateral canals 60 ms gains on vHIT ( r = 0.225, p = 0.026). Significant correlation between oVEMP and vHIT asymmetry was present in VN patients ( r = 0.749, p < 0.001), while no correlation was found in the groups 2 and 3. oVEMP and vHIT lateral canals asymmetries were significantly greater in patients with vestibular neuritis. Furthermore, positive correlations of oVEMP amplitudes with 60 ms gain of the lateral semicircular canal and slope of the anterior semicircular canal on vHIT, and cVEMP with slope of the posterior semicircular canal on the vHIT were found. These changes were significantly more pronounced in patients with vestibular neuritis. In conclusion, VEMPs and vHIT data should be used complementarily; asymmetry on both tests strongly supports peripheral vestibular system involvement. [ABSTRACT FROM AUTHOR]

Highlights • The paper reports for the first time Alaria alata mesocercariae in domestic pigs in Serbia. • This is the only reported case in domestic pigs over the past several decades in Europe. • Increasingly popular free-range pig farming may create a risk to animal and public health of alariosis. • The results should influence the growing awareness of alariosis as a potential human disease. • The results may serve as a reason for reconsideration of the appropriate regulations. Abstract Alaria alata (Diplostomidae, Trematoda), a potentially zoonotic pathogen, is the only Alaria species in Europe. In recent years, increasing reports of mesocercariae of A. alata in wild boars have been recorded in European countries; however there have been no described cases in domestic pigs over the past decades. Out of 272 diaphragm samples from wild boars (Sus scrofa) and domestic pigs (Sus scrofa), from Serbia, included in the present investigations, mesocercariae of A. alata were found in six (3%) samples from wild boars and in two (2.77%) samples from domestic pigs. Due to the lack of sensitivity of artificial digestion with a magnetic stirrer which was applied in the study, the true prevalence is estimated to be considerably higher in the area of investigation. Confirming the infection in domestic pigs and a wide distribution in wild boars in the area of investigation, the present paper should influence the growing awareness of alariosis as a potential human disease. The meat from free-range domestic pigs and game meat as a potential source of alariosis should always be adequately thermally treated before consumption. [ABSTRACT FROM AUTHOR]

The dynamic stability problem of a viscoelastic nanobeam subjected to compressive axial loading, where rotary inertia is taken into account, is investigated. The paper is concerned with the stochastic parametric vibrations of a Voigt–Kelvin nanobeam based on Eringen’s nonlocal elasticity theory of the Helmholtz and bi-Helmholtz type of kernel. The axial force consists of a constant part and a time-dependent stochastic function. By using the direct Liapunov method, bounds of the almost sure asymptotic stability of a viscoelastic nanobeam are obtained as a function of retardation time, variance of the stochastic force, geometric ratio, scale coefficients, and intensity of the deterministic component of axial loading. Numerical calculations were done for the Gaussian and harmonic process. When the excitation is a real noise process, the advanced numerical simulation based on the Monte Carlo method is presented for moment Liapunov exponents numerical determination. [ABSTRACT FROM AUTHOR]

Abstract: The essential oil from underground parts of Ferula heuffelii from N.E. Serbia, was analysed using GC and GC–MS. The main compounds of the essential oil were elemicin (35.4%) and myristicin (20.6%). The essential oil exhibited the best antimicrobial activity against two strains of Candida albicans (MIC=7.0 and 13.7μg/ml), as well as against Micrococcus luteus (MIC=13.7μg/ml), Staphylococcus epidermidis (MIC=17.6μg/ml), Bacillus subtilis (MIC=21.1μg/ml) and Micrococcus flavus (MIC=28.2μg/ml). In the DPPH radical scavenging assay, essential oil showed substantial activity with SC50 =22.43μl/ml. The essential oil was also tested for antispasmodic activity. It inhibited spontaneous contraction of isolated rat ileum dose-dependently, and at the concentration of 86.64μg/ml exhibited 50% of the maximum effect of atropine. After incubation with 75.00μg/ml of essential oil, acetylcholine did not induce contractions of ileum, and at 250.00μg/ml, the essential oil almost completely abolished the spasmodic effect of potassium chloride (80mM). [Copyright &y& Elsevier]

Abstract: An alternative to clinical trial paper-based data collection (PDC) is internet based electronic data collection (EDC), where the investigators over the internet enter data directly in the electronic database by themselves. In our study we considered clinical trial as a business process. Our objective was to model PDC and EDC process and to estimate the difference of the costs of PDC and EDC process for a sample clinical trial based on these models. We used Extended Event-driven Process Chains (eEPC) modeling technique to model PDC and EDC process. In order to evaluate the costs of the processes we assigned costs functions to each process function which appears in the model. The parameters which appear in these functions include efforts, staff prices and data quality parameters. We estimated the values of all these parameters and performed costs calculations for a sample clinical trial. Through an analysis and modeling efforts we identified sub-processes which contain main differences affecting duration and costs of the PDC and EDC process: data gathering at the research center; monitoring; and data management. The most significant model difference between PDC and EDC process appeared in data management sub-process. For the sample clinical trial considered in our simulation study and our parameters estimations the EDC process decreased data collection costs for 55%. For different scenarios of parameters variations we show that the EDC process may bring from 49% to 62% of savings when compared to PDC process. [Copyright &y& Elsevier]

Abstract: The stochastic instability problem associated with an axially loaded cross-ply laminated beam is formulated. The effects of shear deformation and rotatory inertia are included in the present formulations. The beam is subjected to time-dependent deterministic and stochastic forces. By using the direct Liapunov method, bounds for the almost sure instability of beams as a function of viscous damping coefficient, variance of the stochastic force, ratio of principal lamina stiffnesses, shear correction factor, number of layers, mode numbers and geometrical ratio, are obtained. Numerical calculations are performed for the Gaussian process with a zero mean and variance σ 2 as well as for harmonic process with an amplitude A. [Copyright &y& Elsevier]

Abstract: On the basis of the Bernoulli–Euler beam theory, the stability and instability of a double-beam system subjected to compressive axial loading is investigated. It is assumed that the two beams of the system are simply supported and continuously joined by a Winkler elastic layer. Each pair of axial forces consists of a constant part and a time-dependent stochastic function. By using the direct Lyapunov method, bounds of the almost sure stability and instability and uniform stochastic stability of a double-beam system as a function of viscous damping coefficient, bending stiffness, stiffness modulus of the Winkler layer, variances of the stochastic forces, and intensity of the deterministic components of axial loading are obtained. When the almost sure stability and instability are investigated, numerical calculations are performed for the Gaussian process with a zero mean as well as a harmonic process with random phase. When axial forces are white noise processes, conditions for uniform stochastic stability are determined. [Copyright &y& Elsevier]

Abstract: The dynamic stability problem of a viscoelastic Voigt–Kelvin rotating shaft subjected to action of axial forces at the ends is studied. The shaft is of circular cross-section, it rotates at a constant rate about its longitudinal axis of symmetry. The effect of rotatory inertia of the shaft cross-section is included in the present formulation. Each force consists of a constant part and a time-dependent stochastic function. Closed form analytical solutions are obtained for simply supported boundary conditions. By using the direct Liapunov method almost sure asymptotic stability conditions are obtained as the function of stochastic process variance, retardation time, angular velocity, and geometric and physical parameters of the shaft. Numerical calculations are performed for the Gaussian process with a zero mean and variance σ 2 as well as for harmonic process with amplitude H. [Copyright &y& Elsevier]

This communication presents the thermal vibration and stability analysis of the multi-layered graphene sheets (MLGS) modeled as multi-nanoplate system (MNPS) embedded in an elastic medium. Nonlocal elasticity and Kirchhoff–Love plate theories are used for nanoplates, which are considered as orthotropic. Elastic medium is represented by the Winkler’s spring model, which couples adjacent nanoplates in MNPS. Governing equations are derived and exact closed form solutions for nonlocal frequencies, critical buckling loads and critical buckling temperature are obtained by using the Navier’s and trigonometric methods. The analytical results are validated with the corresponding results in the literature, results obtained via molecular dynamics simulation and numerical method of solution of the system of algebraic equations. To consider the thermal effects on the vibration and stability behavior of MNPS we adopted the coefficient of thermal expansion (CTE) obtained from the experimental results found in the literature. In the parametric study, effects of temperature change, nonlocal parameter, number of nanoplates and change of mediums stiffness on dimensionless nonlocal frequencies, critical buckling load and critical buckling temperature are investigated. [ABSTRACT FROM AUTHOR]

Abstract: The dynamic stability problem of the symmetrically laminated cross-ply plates made of the viscoelastic Voigt–Kelvin material, compressed by time-dependent stochastic membrane forces, is investigated. The effect of rotatory inertia is included in the present formulation. It is assumed that all elastic moduli have the same retardation times. By using the direct Liapunov method, bounds of the almost sure stability of cross-ply plates as a function of viscous damping coefficient, retardation time, variances of the stochastic forces, ratio of the principal lamina stiffnesses, number of layers, plate aspect ratio, cross-ply ratio and intensity of the deterministic components of axial loading are obtained. Numerical calculations are performed for the Gaussian process with a zero mean, as well as an harmonic process with random phase. [Copyright &y& Elsevier]