0000000000625189
AUTHOR
G. Failla
A Fractional Approach to Non-Newtonian Blood Rheology in Capillary Vessels
In small arterial vessels, fluid mechanics involving linear viscous fluid does not reproduce experimental results that correspond to non-parabolic profiles of velocity across the vessel diameter. In this paper, an alternative approach is pursued introducing long-range interactions that describe the interactions of non-adjacent fluid volume elements due to the presence of red blood cells and other dispersed cells in plasma. These non-local forces are defined as linearly dependent on the product of the volumes of the considered elements and on their relative velocity. Moreover, as the distance between two volume elements increases, the non-local forces decay with a material distance-decaying …
A Galerkin approach for power spectrum determination of nonlinear oscillators
A numerical method to estimate spectral properties of nonlinear oscillators with random input is presented. The stationary system response is expanded into a trigonometric Fourier series. A set of nonlinear algebraic equations, solved by Newton's method, leads to the determination of the unknown Fourier series coefficients of single samples of the response process. For cubic polynomial nonlinearities, closed-form expressions are used to find the nonlinear terms at each step of the solution scheme. Further, a simple procedure yields an approximation of an arbitrary nonlinearity by a cubic polynomial. Power spectral density estimates for the response process are constructed by averaging the s…
Moving multi-loads problem in layered cracked beams with interlayer slip
This contribution concerns the vibration response of layered cracked uniform beams with interlayer slip under moving multiple loads. Considering a linear constitutive relation between the horizontal slip and the interlaminar shear force, the Euler-Bernoulli hypothesis is assumed to hold for each layer separately. Modeling cracks as internal elastic rotational joints, related discontinuities of the response variables are treated by the theory of generalized functions. In this manner, exact eigenfunctions are derived from a characteristic equation built as determinant of 6x6 matrix, for any number of cracks. Building pertinent orthogonality conditions for the deflection eigenfunctions, the re…
A novel approach to nonlinear variable-order fractional viscoelasticity.
This paper addresses nonlinear viscoelastic behaviour of fractional systems with variable time-dependent fractional order. In this case, the main challenge is that the Boltzmann linear superposition principle, i.e. the theoretical basis on which linear viscoelastic fractional operators are formulated, does not apply in standard form because the fractional order is not constant with time. Moving from this consideration, the paper proposes a novel approach where the system response is derived by a consistent application of the Boltzmann principle to an equivalent system, built at every time instant based on the fractional order at that instant and the response at all the previous ones. The ap…
Doxorubicin-docetaxel sequential schedule: results of front-line treatment in advanced breast cancer.
<i>Objective:</i> We conducted a multi-institutional phase II study to evaluate the tolerability and activity of a sequential schedule of treatment with doxorubicin and docetaxel in chemotherapy-naive women with advanced breast cancer. <i>Methods:</i> A total of 73 patients with PS (ECOG) 0–2, aged <70 years and adequate bone marrow, renal, liver and cardiac functions were included in the study (13 stage III B and 60 stage IV). The schedule of administration was doxorubicin 50 mg/m<sup>2</sup> by intravenous (i.v.) 30 min injection on day 1 followed the day after by docetaxel 75 mg/m<sup>2</sup>, by i.v. 60 min infusion. Cycles were repeate…