Ricerc@Sapienza

We study the effects of cation inversion x (Mg ↔ Al, with x representing the fraction of Mg and Al exchanged) and magnetic substitution (Mn → Mg) on the elastic properties of the MgAl2O4 spinel system using density functional theory and Brillouin scattering techniques. Our computations show that cation inversion decreases the molar volume of spinel and produces a stiffening of C11 and a softening of C12. Simulations and experiments agree within 2%. Density functional theory also captures the qualitative effect of Mg ↔ Al on C44, that is, an initial softening for inversion degree at x

We investigated by a multi-analytical approach (Brillouin scattering, X-ray diffraction and electron microprobe) the dependence of the elastic properties on the chemical composition of six spinels in the series (Mg1−x,Fex)Al2O4(0 ≤ x ≤ 0.5). With the exception of C12, all the elastic moduli (C11, C44, KS0and G) are insensitive to chemical composition for low iron concentration, while they decrease linearly for higher Fe2+content. Only C12shows a continuous linear increase with increasing Fe2+across the whole compositional range under investigation.

Objectives The myotendinous junction (MTJ) represents a specialized anatomic region through which the contractile strength is transmitted from the muscle to the tendon. The integrity of this region is essential to permit force transmission and to optimize energy expenditure during walking, running, and globally for human movement. We evaluated the MTJ with shear wave elastography to assess its elasticity variation during a functional test.Methods Forty professional soccer players were enrolled in the study.

We introduce a continuum model for a fibre reinforced material in which the reference orientation of the fibre may evolve with time, under the influence of external stimuli. The model is formulated in the framework of large strain hyperelasticity and the kinematics of the continuum is described by both a position vector and by a remodelling tensor which, in the present context, is an orthogonal tensor representing the fibre reorientation process.

The effects that an increase of environmental pH has on the triple helix of scleroglucan (Sclg)
and on the Sclg/borax hydrogel are reported. Rheological experiments show that the hydrogel is less
sensitive to pH increase than Sclg alone, while at pH = 14 a dramatic viscosity decrease takes place for
both systems. This effect is evidenced also by the reduced water uptake and anisotropic elongation
detected, at pH = 14, by the swelling behaviour of tablets prepared with the Sclg/borax system.

Distributed stream processing frameworks are designed to perform continuous computation on possibly unbounded data streams whose rates can change over time. Devising solutions to make such systems elastically scale is a fundamental goal to achieve desired performance and cut costs caused by resource over-provisioning. These systems can be scaled along two dimensions: the operator parallelism and the number of resources. In this paper, we show how these two dimensions, as two symbiotic entities, are independent but must mutually interact for the global benefit of the system.

The design of an efficient drug delivery platform relies on the fabrication of a suitable polymeric network that can modulate the release of therapeutic molecules. In this study, we aimed to reach this goal by fabricating a novel nanocomposite double network (nDN) hydrogel, which contains the synthetic clay Laponite as the nanofiller necessary to influence the mechanical, physical and releasing properties of the designed carrier.