Optimal fault-tolerant placement of relay nodes in a mission critical wireless network

The operations of many critical infrastructures (e.g., airports) heavily depend on proper functioning of the radio communication network supporting operations. As a result, such a communication network is indeed a mission-critical communication network that needs adequate protection from external electromagnetic interferences. This is usually done through radiogoniometers. Basically, by using at least three suitably deployed radiogoniometers and a gateway gathering information from them, sources of electromagnetic emissions that are not supposed to be present in the monitored area can be localised. Typically, relay nodes are used to connect radiogoniometers to the gateway. As a result, some degree of fault-tolerance for the network of relay nodes is essential in order to offer a reliable monitoring. On the other hand, deployment of relay nodes is typically quite expensive. As a result, we have two conflicting requirements: minimise costs while guaranteeing a given fault-tolerance. In this paper address the problem of computing a deployment for relay nodes that minimises the relay node network cost while at the same time guaranteeing proper working of the network even when some of the relay nodes (up to a given maximum number) become faulty (fault-tolerance). We show that the above problem can be formulated as a Mixed Integer Linear Programming (MILP) as well as a Pseudo-Boolean Satisfiability (PB-SAT) optimisation problem and present experimental results com- paring the two approaches on realistic scenarios

Surgical treatment of tertiary hyperparathyroidism: does one fit for all?

BackgroundTertiary hyperparathyroidism (3HPT) is defined as a condition of excessive autonomous excretion of intact parathyroid hormone (iPTH) with persistent hypercalcemia (>10.5 mg/dL) that lasts for more than 12 months after a successful kidney transplantation, in the context of a long course secondary hyperparathyroidism (2HPT). The chronic high levels of iPTH cause a worsening of graft function, accompanied by systemic symptoms of hypercalcemia. The only curative therapy is parathyroidectomy (PTX). It remains unclear whether total parathyroidectomy with autotransplantation (TPTX-AT) or subtotal parathyroidectomy (SPTX) lead to better outcomes.AimsThe aim of this retrospective, single-institution cohort study is to evaluate the rate of persistent or recurrent disease and postoperative calcium/iPTH disturbances in patients treated with TPTX-AT or SPTX for 3HPT.MethodsA single-center retrospective analysis of 3HPT patients submitted to TPTX-AT or SPTX between 2007–2020 with at least 24 months follow-up was conducted. The outcome parameters included persistence/recurrence of disease, incidence of transitory hypocalcemia, and temporary/permanent hypoparathyroidism.ResultsA cohort of 52 patients was analyzed and divided in two groups: 38 (73%) were submitted for TPTX-AT, and 14 patients (27%) were submitted for SPTX. The TPTX-AT population showed lower plasmatic calcium concentrations compared with the SPTX group during the entire follow-up period (p<0.001). There were eight cases (21%) of transitory hypocalcemia in the TPTX-AT group and none in the SPTX group, with p=0.065. Two cases (5%) of temporary hypoparathyroidism occurred in the TPTX-AT group and none in the SPTX group, with p= 0.530. There were no cases of permanent hypoparathyroidism and no cases of persistent disease. No statistical difference was assessed for the recurrence of 3HPT between the TPTX-AT group and the SPTX group (N=1, 3% vs N=1, 7%) (p=0.470).ConclusionNo significative difference was registered between the TPTX-AT and SPTX groups in terms of persistence/recurrence of disease, incidence of transitory hypocalcemia, and temporary/permanent hypoparathyroidism. Mean calcium levels iPTH values were statistically lower among the TPTX-AT group compared with the SPTX group while remaining always in the range of normality

Can quantum fractal fluctuations be observed in an atom-optics kicked rotor experiment?

We investigate the parametric fluctuations in the quantum survival probability of an open version of the delta-kicked rotor model in the deep quantum regime. Spectral arguments [Guarneri I and Terraneo M 2001 Phys. Rev. E vol. 65 015203(R)] predict the existence of parametric fractal fluctuations owing to the strong dynamical localisation of the eigenstates of the kicked rotor. We discuss the possibility of observing such dynamically-induced fractality in the quantum survival probability as a function of the kicking period for the atom-optics realisation of the kicked rotor. The influence of the atoms' initial momentum distribution is studied as well as the dependence of the expected fractal dimension on finite-size effects of the experiment, such as finite detection windows and short measurement times. Our results show that clear signatures of fractality could be observed in experiments with cold atoms subjected to periodically flashed optical lattices, which offer an excellent control on interaction times and the initial atomic ensemble.Comment: 18 pp, 7 figs., 1 tabl

Protective effects of melatonin against nicotine-induced oxidative damage of kidney

Several studies demonstrated that melatonin treatment prevents tissue damage in various models of oxidative stress (1). Experiments have shown that chronic nicotine administration caused oxidant damage in various organs by increasing lipid peroxidation products and decreasing the activity of endogenous antioxidants (2). The aim of this study was to investigate the effects of melatonin treatment on nicotine-induced oxidative changes in rat kidney and to explore the possible mechanisms of action. Three groups of rats were used as controls (the first without treatment, the second with melatonin alone and the third with nicotine alone). The last group of rats was orally treated with nicotine and melatonin for 28 days. Morphological changes in kidney were evaluated by histological procedures and immunohistochemical analysis using inflammation (NFkB and IL-6) and oxidative stress (SOD, CAT and iNOS) markers. Experiments performed demonstrated that nicotine administration increases inflammation and oxidative stress. Melatonin has a protective effect against nicotine kidney toxicity through an inhibition of inflammation and consequent oxidative damage. These data suggest that melatonin supplementation effectively counteracts the deleterious effect of chronic nicotine administration on kidney and attenuates oxidative damage possibly by its anti-inflammatory and antioxidant effects.This work was supported by grants from University of Brescia (EX 60%)

Head–neck melanoma: Clinical, histopathological and prognostic features of an Italian multicentric study

factor. As regards the scalp, some studies indicate a particularly aggressive biological behaviour for this anatomical localisation. Objectives: In this multicentric study, data regarding head–neck melanoma (HNM) have been revised. Methods: The design of the study included two main phases. In this retrospective study, data regarding HNM have been collected and analysed. Results: In summary, our data suggest that the posterior neck is the area most affected by thicker melanomas. Cheeks and neck melanoma are associated with reduced disease‐free years of life and overall survival compared with all other sites of HNM. Conclusions: This study provides useful information in defining the clinical features of HNM, thus improving diagnosis and treatment strategies

Head–neck melanoma: Clinical, histopathological and prognostic features of an Italian multicentric study

BackgroundPrimitive location of melanoma could be a relevant prognostic factor. As regards the scalp, some studies indicate a particularly aggressive biological behaviour for this anatomical localisation.ObjectivesIn this multicentric study, data regarding head-neck melanoma (HNM) have been revised.MethodsThe design of the study included two main phases. In this retrospective study, data regarding HNM have been collected and analysed.ResultsIn summary, our data suggest that the posterior neck is the area most affected by thicker melanomas. Cheeks and neck melanoma are associated with reduced disease-free years of life and overall survival compared with all other sites of HNM.ConclusionsThis study provides useful information in defining the clinical features of HNM, thus improving diagnosis and treatment strategies.Primitive location of melanoma could be a relevant prognostic factor. In this multicentric study, data regarding head-neck melanoma (HNM) have been revised.Our data suggest that posterior neck is the area most affected by thicker melanomas. Cheeks and neck melanoma are associated with reduced disease-free years of life and overall survival compared with all other sites of HNM.This study provides useful information in defining the clinical features of HNM, thus improving diagnosis and treatment strategies. imag