SYMMETRIES AND BLACK HOLESIN N = 2GAUGED SUPERGRAVITY

The main goal of this work is to explore the role and the power of the Hamilton-Jacobi approach and solutions generating techniques to search black hole solutions in abelian gauged supergravity theories. After a brief introduction explaining how supergravity arises as effective theory of superstrings, a chapter is devoted to the detailed description of N = 2 abelian gauged supergravity in d = 4 and d = 5. The study of the equations of motion with general matter coupling for static black hole solutions is developed with Hamilton-Jacobi approach and new first order sets of equa- tions are presented [1, 2] extending well-known BPS sets [3, 4]. In d = 5 the equations are completely solved for the STU model with constant hypermultiplets and a solution generalizing Maldacena-Nunez black string [4] is found [5]. Then the attention is focused on some integrability properties of minimal gauged super- gravity in d = 4 [6] and Einstein-Maxwell-Lambda system in d dimensions [7]. Always with Hamilton-Jacobi technique, studying the symmetries of the systems the dynamics is solved algebraically for some sets of solutions. For holographic calculations the attractor points deserve particular attention and there- fore I explain their definition for the cases AdS 2 7 \u3a3 2 and AdS 3 7 \u3a3 2 and the calculation of the entropy and the central charge in general matter coupled supergravities. More- over, Freudenthal duality is extended to the abelian gauged case and general matter coupling [8]. The last part is dedicated to the introduction of a solution generating technique based on group theory in FI d = 4 supergravity. Many examples with the simplest prepotentials are shown [9]. With the help of dimensional reduction this solution generating technique is used to produce a rotating black string in d = 5 [5]

AdS5 black strings in the stu model of FI-gauged N = 2 supergravity

We analytically construct asymptotically AdS5 black string solutions starting from the four-dimensional domain wall black hole of [1]. It is shown that its uplift gives a black string in d = 5 minimal gauged supergravity, with momentum along the string. Applying instead the residual symmetries of N = 2, d = 4 Fayet-Iliopoulos-gauged super-gravity discovered in [2] to the domain wall seed leads, after uplifting, to a dyonic black string that interpolates between AdS5 and AdS3 7 H2 at the horizon. A Kaluza-Klein reduction of the latter along an angular Killing direction \u3d5 followed by a duality transformation yields, after going back to five dimensions, a black string with both momentum along the string and rotation along \u3d5. This is the first instance of using solution-generating techniques in gauged supergravity to add rotation to a given seed. These solutions all have constant scalar fields. As was shown in [3], the construction of supersymmetric static magnetic black strings in the FI-gauged stu model amounts to solving the SO(2, 1) spinning top equations, which descend from an inhomogeneous version of the Nahm equations. We are able to solve these in a particular case, which leads to a generalization of the Maldacena-Nu\uf1ez solution

Symplectically invariant flow equations for N = 2, D = 4 gauged supergravity with hypermultiplets

We consider N = 2 supergravity in four dimensions, coupled to an arbitrary number of vector- and hypermultiplets, where abelian isometries of the quaternionic hyperscalar target manifold are gauged. Using a static and spherically or hyperbolically symmetric ansatz for the fields, a one-dimensional effective action is derived whose variation yields all the equations of motion. By imposing a sort of Dirac charge quantization condition, one can express the complete scalar potential in terms of a superpotential and write the action as a sum of squares. This leads to first-order flow equations, that imply the second-order equations of motion. The first-order flow turns out to be driven by Hamilton\u2019s characteristic function in the Hamilton-Jacobi formalism, and contains among other contributions the superpotential of the scalars. We then include also magnetic gaugings and generalize the flow equations to a symplectically covariant form. Moreover, by rotating the charges in an appropriate way, an alternative set of non-BPS first-order equations is obtained that corresponds to a different squaring of the action. Finally, we use our results to derive the attractor equations for near-horizon geometries of extremal black holes

Long-term disease-free survival in surgically-resected oral tongue cancer: a 10-year retrospective study

Sopravvivenza libera da malattia a lungo termine nel tumore della lingua mobile operato: studio retrospettivo a 10 anni.PLAIN-LANGUAGE-SUMMARY: Early and loco-regionally advanced oral tongue squamous cell carcinoma (OTSCC) can be treated by surgery alone or followed by adjuvant radiotherapy or chemoradiotherapy. Nevertheless, up to 40% of patients develop tumour relapse. The aim of our study is to investigate the clinical and pathological features associated with reduced disease-free survival (DFS) in a cohort of surgically-resected OTSCC patients. One hundred and six patients surgically resected for OTSCC were retrospectively identified from clinical records. DFS was calculated according to the Kaplan\u2013Meier method and differences between variables were assessed with Log-Rank test. A multivariable Cox regression model was used to analyse the impact of different prognostic factors on DFS. After a median of follow-up of 8.9 years, 22 events, including 11 deaths, were observed. Overall, the 5-year DFS-rate was 87.4%. The presence of extra-nodal extension (p = 0.023) and perineural invasion (p = 0.003) were significantly correlated with shorter DFS (in univariate analysis). In multivariable analysis, extra-nodal extension and perineural invasion confirmed their role as independent prognostic factors associated with an increased risk of disease recurrence [hazard ratio (HR) 2.87, 95% CI 1.11-7.42, p = 0.03; HR 3.85, 95% CI 1.49-9.96, p = 0.006, respectively]. p16 and p53 expressions in tumour cells were detected in 12% (n = 9) and 46% (n = 40) of cases, respectively. No differences in DFS were observed between p16+ and p16- (p = 0.125) and between p53+ and p53- tumours (p = 0.213). In conclusion, radical surgery, eventually followed by adjuvant radiotherapy or chemo-radiotherapy, can achieve high cure rates in OTSCC. After long-term follow-up, perineural invasion and extra-nodal extension confirmed their role as prognostic factors associated with reduced DFS in OTSCC patients

Technical refinements in mandibular reconstruction with free fibula flaps: Outcome-oriented retrospective review of 99 cases = Accorgimenti tecnici nelle ricostruzioni mandibolari con lembi liberi di fibula: analisi retrospettiva dei risultati su 99 casi

Congenital disease, major trauma, tumour resection and biphosphonate-related osteonecrosis can lead to partial, subtotal, or total loss of the mandibular bone. Minor defects can be easily reconstructed using bone grafts, whereas microvascular free tissue transfer may be unavoidable in the case of major bone loss or poor quality of soft tissue. Simple bone or composite osteocutaneous fibula free flaps have proven invaluable and remain the workhorse for microvascular mandibular reconstruction in daily practice. Our experience with 99 consecutive fibular free flaps confirms the available data in terms of high success rate. In these cases, 90% had total success, while 7 had complete flap failures. Three of our patients showed skin paddle necrosis with bony conservation. This report focuses on the technical refinements used by the authors that can prove valuable in obtaining predictable and precise results: in particular, we discuss surgical techniques that avoid vascular pedicle ossification by removing the fibular periosteum from the vascular pedicle itself and reduce donor site morbidity and aid in management of the position in the new condylar fossa. Finally, new technologies such as intraoperative CT and custom premodelled fixation plates may also increase the predictability of morpho-functional results

Organizational design and firms performance

none3M.G. Colombo; M. Delmastro; L. RabbiosiColombo, MASSIMO GAETANO; M., Delmastro; Rabbiosi, Lariss