The public safety zones around small and medium airports

Proper planning around airports safeguards the surrounding territory from risks of air accidents. Many countries have defined Public Safety Zones (PSZs) beyond the runway thresholds as a result of targeted risk assessment methods. Therefore, national aviation Authorities could limit building construction and industrial development in order to contain the risk for dwellers to be involved in aircraft accidents. The number of people who live, work or congregate in these areas should be limited. The procedure to set Public Safety Zones is based on advanced technical analyses for major infrastructures. For smaller airports, simplified schemes are used, but, sometimes, they are not as effective when considering the actual safety conditions. This article aims to identify the shape and size of the Public Safety Zones for small and medium one-runway airports. The influence of the volume and mix of traffic on the PSZ geometry has been evaluated using the program named SARA (Sapienza Airport Risk Analysis); the results are correlated with the current Risk Plans generally adopted in Italy. According to the air traffic, the Risk Plans are characterized by a dynamic definition and fit the results obtained from risk assessment

't Hooft loop and the phases of SU(2) LGT

We analyze the vacuum structure of SU(2) lattice gauge theories in D=2,3,4, concentrating on the stability of 't Hooft loops. High precision calculations have been performed in D=3; similar results hold also for D=4 and D=2. We discuss the impact of our findings on the continuum limit of Yang-Mills theories.Comment: 7 pages, 3 figures. Presented at the 31st International Symposium on Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, German

Femoral Head Autograft to Manage Acetabular Bone Loss Defects in THA for Crowe III Hips by DAA: Retrospective Study and Surgical Technique

Introduction: The pathologic anatomy of Crowe III is characterized by the erosion of the superior rim of acetabulum, with a typical bone defect in its supero–lateral portion. The performance of a total hip arthroplasty requires the management of the acetabular bone defect, and femoral head autograft can be a valid option to optimize implant coverage. Material and Methods: In all, eight Crowe III patients (nine hips), seven of which having unilateral hip affected, and one with bilateral involvement by secondary osteoarthritis in DDH; maximum limb length discrepancy (LLD) of 3.5 cm in unilateral patients. All were operated on by direct anterior approach. Patients were evaluated in terms of clinical, surgical, and radiological (center-edge, horizontal coverage, cup inclination) parameters. Results: Cup placement was implanted with a mean of 39.5 ± 7.5°. Stem alignment showed average 1.5 ± 2.3° in valgus. LLD showed an overall average preoperative of −29.5 ± 10.5 mm at the affected side, with a significant improvement to −2.5 ± 6.4 mm (p = 0.023). The mean initial coverage evaluated like a percentage of the horizontal bone host was 52.1 ± 7.1%, while the mean final coverage at the last post-operative X-ray from femoral autograft bone was 97.0 ± 4.5% with an average improvement of 44.5%. Average CE improved from −9.5 ± 5.2° (CE I) to the immediate post-operative (CE II) of 40.6 ± 8.2°. At the final follow up, CE III showed a mean of 38.6 ± 6.2°, with an average decrease of 2.0°. Discussion: Acetabular bone defect in Crowe III DDH patients undergoing THA by DAA, can be efficiently managed by massive autograft femoral head, which allowed an adequate and long-lasting coverage of the implant, with cup positioning at the native acetabulum

Extended d_{x^2 - y^2}-wave superconductivity

Remarkable anisotropic structures have been recently observed in the order parameter Delta_k of the underdoped superconductor Bi-2212. Such findings are strongly suggestive of deviations from a simple d_{x^2 - y^2}-wave picture of high-Tc superconductivity, i.e. Delta_k ~ cos (k_x) - cos (k_y). In particular, flatter nodes in Delta_k are observed along the k_x = (+/-) k_y directions in k-space, than within this simple model for a d-wave gap. We argue that nonlinear corrections in the k-dependence of Delta_k near the nodes introduce new energy scales, which would lead to deviations in the predicted power-law asymptotic behaviour of several measurable quantities, at low or intermediate temperatures. We evaluate such deviations, either analytically or numerically, within the interlayer pair-tunneling model, and within yet another phenomenological model for a d-wave order parameter. We find that such deviations are expected to be of different sign in the two cases. Moreover, the doping dependence of the flatness of the gap near the nodes is also attributable to Fermi surface effects, in addition to possible screening effects modifying the in-plane pairing kernel, as recently proposed.Comment: 7 pages, 4 embedded PostScript figures. Uses svjour, epsfig, amsmath, amssymb, xspace. To be published in Eur. Phys. J.