Condensation phenomena in nonlinear drift equations

We study nonnegative, measure-valued solutions to nonlinear drift type equations modelling concentration phenomena related to Bose-Einstein particles. In one spatial dimension, we prove existence and uniqueness for measure solutions. Moreover, we prove that all solutions blow up in finite time leading to a concentration of mass only at the origin, and the concentrated mass absorbs increasingly the mass converging to the total mass as time goes to infinity. Our analysis makes a substantial use of independent variable scalings and pseudo-inverse functions techniques

L’analisi delle simbolizzazioni affettive delle Aree Naturali Protette per un turismo responsabile. Il caso studio delle Riserva Naturale Orientata dello Zingaro.

ABSTRACT This paper presents a research on responsible tourism in protected areas, through the case study of Zingaro Nature Reserve (Sicily). The main objectives of this study were to examine the so-called collusive processes elaborated by different stakeholder of natural protected area and to propose strategies and guidelines for intervention in the perspective of sustainable development and responsible use of the local tourist activities, based on the results. The methodology applied was Emotional Analysis of the Text (EAT) that allowed to investigate the emotional representations and the expectations of stakeholders, through the study of co-occurrances of the so-called dense words, using the statistical software for textual analysis T-LAB

Vitiligo, NB-UVB and tacrolimus: our experience in Naples.

Aim: The aim of the present study was to evaluate the efficacy and safety of narrowband UVB (NB-UVB) compared with tacrolimus ointment 0.1% in patients with bilateral vitiligo. Methods: In this comparative study, four groups of patients were randomized. Each group was composed by 12 patients with bilateral vitiligo; in each group, every patient was irradiated with NB-UVB (length: 311 nm) twice a week for 9 months and applied tacrolimus ointment 0.1% twice a day on the other area in the same period. Before starting therapy and after 3, 6 and 9 months of therapy, a clinical and photographic evaluation of percentage of repigmentation was performed and Dermatology Life Quality Index Questionnaire was fulfilled. Results: A repigmentation at least partial occurred in 71% of patients after 36 weeks of treatment with tacrolimus ointment 0.1%; in the whole sample, 14 patients (29%) showed no repigmentation at all, with 2 of them discontinuing the therapy because of side effects (erythema and folliculitis-like manifestations). A homogeneous repigmentation at least partial occurred in 69% of patients after 36 weeks of treatment with NB-UVB; in the whole sample 15 patients (31%) showed no repigmentation at all, with 1 of them discontinuing the therapy because of side effects. Conclusion: The present study confirmed that the efficacy of NB-UVB phototherapy in vitiligo is comparable to tacrolimus ointment 0.1% therapy. On the basis of our study, we may suggest tacrolimus ointment 0.1% as an alternative to NB-UVB therapy for treating vitiligo

A genetic algorithm for the design of a fuzzy controller for active queue management

Active queue management (AQM) policies are those policies of router queue management that allow for the detection of network congestion, the notification of such occurrences to the hosts on the network borders, and the adoption of a suitable control policy. This paper proposes the adoption of a fuzzy proportional integral (FPI) controller as an active queue manager for Internet routers. The analytical design of the proposed FPI controller is carried out in analogy with a proportional integral (PI) controller, which recently has been proposed for AQM. A genetic algorithm is proposed for tuning of the FPI controller parameters with respect to optimal disturbance rejection. In the paper the FPI controller design metodology is described and the results of the comparison with random early detection (RED), tail drop, and PI controller are presented

Photonic circuits for generating modal, spectral, and polarization entanglement

We consider the design of photonic circuits that make use of Ti:LiNbO$_{3}$ diffused channel waveguides for generating photons with various combinations of modal, spectral, and polarization entanglement. Down-converted photon pairs are generated via spontaneous optical parametric down-conversion (SPDC) in a two-mode waveguide. We study a class of photonic circuits comprising: 1) a nonlinear periodically poled two-mode waveguide structure, 2) a set of single-mode and two-mode waveguide-based couplers arranged in such a way that they suitably separate the three photons comprising the SPDC process, and, for some applications, 3) a holographic Bragg grating that acts as a dichroic reflector. The first circuit produces frequency-degenerate down-converted photons, each with even spatial parity, in two separate single-mode waveguides. Changing the parameters of the elements allows this same circuit to produce two nondegenerate down-converted photons that are entangled in frequency or simultaneously entangled in frequency and polarization. The second photonic circuit is designed to produce modal entanglement by distinguishing the photons on the basis of their frequencies. A modified version of this circuit can be used to generate photons that are doubly entangled in mode number and polarization. The third photonic circuit is designed to manage dispersion by converting modal, spectral, and polarization entanglement into path entanglement

Levels of heavy metals in wetland and marine vascular plants and their biomonitoring potential : a comparative assessment

The present study investigated the levels of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb and Zn in the seagrasses Posidonia oceanica and Cymodocea nodosa, and in the wetland macrophytes Phragmites australis, Arundo donax, Typha domingensis, Apium nodiflorum, and Nasturtium officinale. Results showed that the bioaccumulation capacity from sediments, translocation, total levels in plant tissues, and bioindication of metals in sediments, are generally species-specific. In particular, the patterns of metals in the aquatic plants studied were overall independent of ecology (coasts vs wetlands), biomass, anatomy (rhizomatous vs non rhizomatous plants), and life form (hemicrytophytes vs hydrophytes). However, marine phanerogams and wetland macrophytes shared some characteristics such as high levels of heavy metals in their below-ground organs, similar capacity of element translocation in the rhizosphere, compartmentalization of metals in the different plant organs, and potential as bioindicators of Cu, Mn and Zn levels in the substratum. In particular, the present findings indicate that, despite ecological and morphological similarities, different plant species tend to respond differently to exposure to heavy metals. Furthermore, this seems to result from the species individual ability to accumulate and detoxify the various metals rather than being attributed to differences in their ecological and morpho-anatomical characteristics.peer-reviewe

Robust Unconditionally Secure Quantum Key Distribution with Two Nonorthogonal and Uninformative States

We introduce a novel form of decoy-state technique to make the single-photon Bennett 1992 protocol robust against losses and noise of a communication channel. Two uninformative states are prepared by the transmitter in order to prevent the unambiguous state discrimination attack and improve the phase-error rate estimation. The presented method does not require strong reference pulses, additional electronics or extra detectors for its implementation.Comment: 7 pages, 2 figure

Feynman graphs and the large dimensional limit of multipartite entanglement

We are interested in the properties of multipartite entanglement of a system composed by $n$ $d$-level parties (qudits). Focussing our attention on pure states we want to tackle the problem of the maximization of the entanglement for such systems. In particular we effort the problem trying to minimize the purity of the system. It has been shown that not for all systems this function can reach its lower bound, however it can be proved that for all values of $n$ a $d$ can always be found such that the lower bound can be reached. In this paper we examine the high-temperature expansion of the distribution function of the bipartite purity over all balanced bipartition considering its optimization problem as a problem of statistical mechanics. In particular we prove that the series characterizing the expansion converges and we analyze the behavior of each term of the series as $d\to \infty$.Comment: 29 pages, 11 figure