Polytechnic University of Milan

About: Polytechnic University of Milan is a education organization based out in Milan, Italy. It is known for research contribution in the topics: Finite element method & Population. The organization has 18231 authors who have published 58416 publications receiving 1229711 citations. The organization is also known as: PoliMi & L-NESS.

Probing non-Hermitian skin effect and non-Bloch phase transitions

Abstract: This paper uncovers a bulk probing method to catch physical effects hindered in topological non-Hermitian crystals. The method is based on Lyapunov exponent calculation of a quantum walker on the lattice and can reveal non-Bloch phase transitions, the non-Hermitian skin effect and breakdown of the bulk-boundary correspondence.

Defining and validating measures for object-based high-level design

Abstract: The availability of significant measures in the early phases of the software development life-cycle allows for better management of the later phases, and more effective quality assessment when quality can be more easily affected by preventive or corrective actions. We introduce and compare various high-level design measures for object-based software systems. The measures are derived based on an experimental goal, identifying fault-prone software parts, and several experimental hypotheses arising from the development of Ada systems for Flight Dynamics Software at the NASA Goddard Space Flight Center (NASA/GSFC). Specifically, we define a set of measures for cohesion and coupling, which satisfy a previously published set of mathematical properties that are necessary for any such measures to be valid. We then investigate the measures' relationship to fault-proneness on three large scale projects, to provide empirical support for their practical significance and usefulness.

Intra-Articular Cytokine Levels in Adolescent Patients after Anterior Cruciate Ligament Tear.

Abstract: The treatment of anterior cruciate ligament (ACL) injuries in children and adolescents is challenging Preclinical and clinical studies investigated ACL repairing techniques in skeletally immature subjects However, intra-articular bioenvironment following ACL tear has not yet been defined in skeletally immature patients The aim of this study was to measure cytokine concentrations in the synovial fluid in adolescent population Synovial levels of IL-1β, IL-1ra, IL-6, IL-8, IL-10, and TNF-α were measured in 17 adolescent patients (15 boys) with ACL tears who underwent ACL reconstruction including acute (5), subacute (7), and chronic (5) phases Femoral growth plates were classified as “open” in three patients, “closing” in eight, and “closed” in six Eleven patients presented an ACL tear associated with a meniscal tear The mean Tegner and Lysholm scores ( ) of all patients were 8 ± 1 and 5076 ± 26, respectively IL-8, TNF-α, and IL-1β levels were significantly greater in patients with “open” physes IL-1ra and IL-1β levels were significantly higher in patients with ACL tear associated with a meniscal tear Poor Lysholm scores were associated with elevated IL-6 and IL-10 levels IL-10 levels positively correlated with IL-6 and IL-8 levels, whereas TNF-α concentration negatively correlated with IL-6 levels Skeletally immature patients with meniscal tears and open growth plates have a characteristic cytokine profile with particularly elevated levels of proinflammatory cytokines including IL-8, TNF-α, and IL-1β This picture suggests that the ACL tear could promote an intra-articular catabolic response in adolescent patients greater than that generally reported for adult subjects The study lacks the comparison with synovial samples from healthy skeletally immature knees due to ethical reasons Overall, these data contribute to a better knowledge of adolescent intra-articular bioenvironment following ACL injuries

In Vivo Quantification of Helical Blood Flow in Human Aorta by Time-Resolved Three-Dimensional Cine Phase Contrast Magnetic Resonance Imaging

Abstract: The mechanics of blood flow in arteries plays a key role in the health of individuals. In this framework, the role played by the presence of helical flow in the human aorta is still not clear in its relation to physiology and pathology. We report here a method for quantifying helical flow in vivo employing time-resolved cine phase contrast magnetic resonance imaging to obtain the complete spatio-temporal description of the three-dimensional pulsatile blood flow patterns in aorta. The method is applied to data of one healthy volunteer. Particle traces were calculated from velocity data: to them we applied a Lagrangian-based method for helical flow quantification, the Helical Flow Index, which has been developed and evaluated in silico in order to reveal global organization of blood flow. Our results: (i) put in evidence that the systolic hemodynamics in aorta is characterized by an evolving helical flow (we quantified a 24% difference in terms of the content of helicity in the streaming blood, between mid and early systole); (ii) indicate that in the first part of the systole helicity is ascrivable mainly to the asymmetry of blood flow in the left ventricle, joined with the laterality of the aorta. In conclusion, this study shows that the quantification of helical blood flow in vivo is feasible, and it might allow detection of anomalies in the expected physiological development of helical flow in aorta and accordingly, could be used in a diagnostic/prognostic index for clinical practice.