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In a non-local fractional-order model of thermal energy transport recently introduced by the authors, it is assumed that local and non-local contributions coexist at a given observation scale: while the first is described by the classical Fourier transport law, the second involves couples of adjacent and non-adjacent elementary volumes, and is taken as proportional to the product of the masses of the interacting volumes and their relative temperature, through a material-dependent, distance-decaying power-law function. As a result, a fractional-order heat conduction equation is derived. This paper presents a pertinent finite element method for the solution of the proposed fractional-order heat conduction equation. Homogenous and non-homogeneous rigid bodies are considered. Numerical applications are carried out on 1D and 2D bodies, including a standard finite difference solution for validation. [ABSTRACT FROM AUTHOR]

The stress-driven nonlocal continuum theory is a well-established integral elasticity formulation. Modelling the elastic strain via a convolution integral between stress and an averaging kernel, the theory leads to an integro-differential structural problem for arbitrary 3D nonlocal solids. Integral elasticity solutions are mainly available for 1D solids by adopting a bi-exponential kernel and reverting the boundary-value integro-differential problem to an equivalent differential formulation involving both classical and constitutive boundary conditions. A general computational framework to implement the stress-driven theory for 3D nonlocal solids is still missing. This paper tackles this issue, solving the relevant integro-differential problem by a two-field finite-element approach involving displacements and stresses. The approach can handle the dynamics of complex small-size structures of arbitrary shape. Focusing on free vibration responses, two examples are presented: a 2D rectangular plate, serving as benchmark to demonstrate size effects captured by stress-driven nonlocal elasticity, and a 3D solid modelling a typical dual microcantilever resonator with overhang. [ABSTRACT FROM AUTHOR]

A stochastic time domain fatigue analysis is pursued on steel tripod and jacket support structures for offshore wind turbines, following the basic concepts of recently validated simplified linear analyses. A set of environmental lumped load cases with corresponding probabilities of occurrence is considered. Results are compared in terms of a lifetime damage equivalent load.

Abstract: A numerical method is presented to compute the response of a viscoelastic Duffing oscillator with fractional derivative damping, subjected to a stochastic input. The key idea involves an appropriate discretization of the fractional derivative, based on a preliminary change of variable, that allows to approximate the original system by an equivalent system with additional degrees of freedom, the number of which depends on the discretization of the fractional derivative. Unlike the original system that, due to the presence of the fractional derivative, is governed by non-ordinary differential equations, the equivalent system is governed by ordinary differential equations that can be readily handled by standard integration methods such as the Runge–Kutta method. In this manner, a significant reduction of computational effort is achieved with respect to the classical solution methods, where the fractional derivative is reverted to a Grunwald–Letnikov series expansion and numerical integration methods are applied in incremental form. The method applies for fractional damping of arbitrary order α (0< α <1) and yields very satisfactory results. With respect to its applications, it is worth remarking that the method may be considered for evaluating the dynamic response of a structural system under stochastic excitations such as earthquake and wind, or of a motorcycle equipped with viscoelastic devices on a stochastic road ground profile. [Copyright &y& Elsevier]

A phase I study of floxuridine circadian infusion was performed in 14 patients with advanced solid tumors (9 colonic, 1 gastric, 4 renal). The starting dose was 0.15 mg/kg/day for 14 days followed by a 14-day therapy-free interval. Sixty-eight percent of the daily dose was infused between 3pm and 9pm. The dose was increased by 0.025 mg/kg/day for each successive course. Eighty-one cycles of therapy were given for a total of 1134 days of treatment. The mean dose intensity was 0.868 mg/kg/day for the entire group. The highest dose achieved (maximum tolerated dose) was 0.325 mg/kg/day. The most frequent toxicity was diarrhea (4.9 % of all courses) and nausea-vomiting (3.7 % of all courses). These side effects were of a low grade and all were resolved without hospitalization. Our results suggest the circadian modulation of floxuridine infusion.

Size-dependent dynamic responses of small-size frames are modelled by stress-driven nonlocal elasticity and assessed by a consistent finite-element methodology. Starting from uncoupled axial and bending differential equations, the exact dynamic stiffness matrix of a two-node stress-driven nonlocal beam element is evaluated in a closed form. The relevant global dynamic stiffness matrix of an arbitrarily-shaped small-size frame, where every member is made of a single element, is built by a standard finite-element assembly procedure. The Wittrick–Williams algorithm is applied to calculate natural frequencies and modes. The developed methodology, exploiting the one conceived for straight beams in [International Journal of Engineering Science 115, 14–27 (2017)], is suitable for investigating free vibrations of small-size systems of current applicative interest in Nano-Engineering, such as carbon nanotube networks and polymer-metal micro-trusses. [ABSTRACT FROM AUTHOR]

No Abstract. Int. J. Cancer 86:448–449, 2000. © 2000 Wiley-Liss, Inc.

Up to two thirds of all patients affected by advanced Hodgkin's disease will be cured by chemotherapy alone or by combined chemoradiation modalities. High-dose chemotherapy with autologous stem cell rescue may be potentially curative for patients progressing under frontline chemotherapy or developing early relapse of disease. In spite of this, an unacceptably high percentage of these highrisk patients will relapse after salvage treatments and die of their disease. Fludarabine phosphate is an adenosine nucleoside analog highly active in chronic lymphocytic leukemia and low-grade non-Hodgkin's lymphomas. There are only few data in the literature concerning its use in the management of Hodgkin's disease. We report the case of an elderly, heavily pretreated Hodgkin's disease patient in progression under third-line chemotherapy who experienced good palliation of her B symptoms and a major clinical response of her refractory bone lesions with the administration of fludarabine as monotherapy. The treatment was well tolerated, without grade 4 hematological toxicity or opportunistic infections. The duration of clinical remission and systemic symptom palliation was 9 and 11 months, respectively. Further evaluation of fludarabine phosphate as salvage therapy in relapsed/refractory elderly Hodgkin's disease patients is needed.

This paper presents a nonlocal Euler-Bernoulli beam model. It is assumed that the equilibrium of a beam segment is attained because of the classical local stress resultants, along with long-range volume forces and moments exchanged by the beam segment with all the nonadjacent beam segments. Elastic long-range volume forces/moments are considered, built as linearly depending on the product of the volumes of the interacting beam segments and on generalized measures of their relative motion, based on the pure deformation modes of the beam. Attenuation functions governing the space decay of the nonlocal effects are introduced. The motion equations are derived in an integro-differential form by applying Hamilton’s principle. Numerical results are presented for a variety of nonlocal parameters. A comparison with experimental data is also provided.

Fractional-order thermodynamics has proved to be an efficient tool to describe several small-scale and/or high-frequency thermodynamic processes, as shown in many engineering and physics applications. The main idea beyond fractional-order physics and engineering relies on replacing the integer-order operators of classical differential calculus with their real-order counterparts. In this study, the authors aim to extend a recently proposed physical picture of fractional-order thermodynamics to a generic 3D rigid heat conductor where the thermal energy transfer is due to two phenomena: a short-range heat flux ruled by stationary and nonstationary transport equations, and a long-range thermal energy transport representing a ballistic effects among thermal energy propagators. Thermodynamic consistency of the model is investigated introducing the state function of the temperature field, namely the entropy, and obtaining the thermodynamic restrictions on the signs of the coefficients involved in the proposed model of fractional-order thermodynamics. Finally, numerical applications are presented for both 1D and 2D rigid bodies.

The paper proposes a fractional calculus approach to continuous wavelet analysis. Upon introducing a Mellin transform expression of the mother wavelet, it is shown that the wavelet transform of an arbitrary function f ( t ) can be given a fractional representation involving a suitable number of Riesz integrals of f ( t ), and corresponding fractional moments of the mother wavelet. This result serves as a basis for an original approach to wavelet analysis of linear systems under arbitrary excitations. In particular, using the proposed fractional representation for the wavelet transform of the excitation, it is found that the wavelet transform of the response can readily be computed by a Mellin transform expression, with fractional moments obtained from a set of algebraic equations whose coefficient matrix applies for any scale a of the wavelet transform. Robustness and computationally efficiency of the proposed approach are shown in the paper. [ABSTRACT FROM AUTHOR]