Cognitive Interference Alignment for OFDM Two-tiered Networks

In this contribution, we introduce an interference alignment scheme that allows the coexistence of an orthogonal frequency division multiplexing (OFDM) macro-cell and a cognitive small-cell, deployed in a two-tiered structure and transmitting over the same bandwidth. We derive the optimal linear strategy for the single antenna secondary base station, maximizing the spectral efficiency of the opportunistic link, accounting for both signal sub-space structure and power loading strategy. Our analytical and numerical findings prove that the precoder structure proposed is optimal for the considered scenario in the face of Rayleigh and exponential decaying channels.Comment: 5 pages, 4 figures. Accepted and presented at the IEEE 13th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2012. Authors' final version. Copyright transferred to IEE

Cognitive Orthogonal Precoder for Two-tiered Networks Deployment

In this work, the problem of cross-tier interference in a two-tiered (macro-cell and cognitive small-cells) network, under the complete spectrum sharing paradigm, is studied. A new orthogonal precoder transmit scheme for the small base stations, called multi-user Vandermonde-subspace frequency division multiplexing (MU-VFDM), is proposed. MU-VFDM allows several cognitive small base stations to coexist with legacy macro-cell receivers, by nulling the small- to macro-cell cross-tier interference, without any cooperation between the two tiers. This cleverly designed cascaded precoder structure, not only cancels the cross-tier interference, but avoids the co-tier interference for the small-cell network. The achievable sum-rate of the small-cell network, satisfying the interference cancelation requirements, is evaluated for perfect and imperfect channel state information at the transmitter. Simulation results for the cascaded MU-VFDM precoder show a comparable performance to that of state-of-the-art dirty paper coding technique, for the case of a dense cellular layout. Finally, a comparison between MU-VFDM and a standard complete spectrum separation strategy is proposed. Promising gains in terms of achievable sum-rate are shown for the two-tiered network w.r.t. the traditional bandwidth management approach.Comment: 11 pages, 9 figures, accepted and to appear in IEEE Journal on Selected Areas in Communications: Cognitive Radio Series, 2013. Copyright transferred to IEE

UK term structure decompositions at the zero lower bound

This paper employs a zero lower bound (ZLB) consistent shadow‐rate model to decompose UK nominal yields into expectation and term premium components. Compared to a standard affine term structure model, it performs relatively better in a ZLB setting by capturing the stylized facts of the yield curve. The ZLB model is then exploited to estimate inflation expectations and risk premiums. This entails jointly pricing and decomposing nominal and real UK yields. We find evidence that medium‐ and long‐term inflation expectations are contained within narrower bounds since the early 1990s, suggesting monetary policy credibility improved after the introduction of inflation targeting

Critical analysis of the manoeuvres proposed for the diagnosis of the tunnel carpal syndrome

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. It is mainly due to the compression of median nerve at the wrist and it may be idiopathic or secondary to different rheumatic or non rheumatic diseases, including occupational activities. Since signs and symptoms of CTS are characteristic, a careful examination of the affected patient may be very satisfactory for the diagnosis, in particular by mean of some manoeuvres. In this review we described and commented the tests considered most useful in the diagnosis of CTS. We also analysed the diagnostic values of electromiography, the most important electrodiagnostic study for the CTS

Electrode-dependent asymmetric conduction mechanisms in K0.5Na0.5NbO3 micro-capacitors

The ultimate performance of devices employing lead-free piezoelectrics is determined not only by the intrinsic properties of the piezo, but also by processes and materials employed to create the electric contacts. In this paper, we investigate the impact of different metallic electrodes with increasing chemical reactivity (Pt, Ni, Ti, Cr), on the asymmetric behavior of the leakage current in M/K0.5Na0.5NbO3/Pt(111) micro-capacitors, where M stands for the top metallic electrode. For all electrodes we found a marked leakage asymmetry that we ascribed to the presence of a Schottky-like rectifying junction at the M/K0.5Na0.5NbO3/Pt(111) bottom interface, while the corresponding junction at the top interface is deeply affected by the creation of oxygen vacancies due to oxygen scavenging during the growth of the top metallic electrodes, leading to an almost ohmic top contact. The leakage increases with the reactivity of the electrodes, while the asymmetry decreases, thus suggesting that the creation of the top metal/K0.5Na0.5NbO3 interface generates oxygen vacancies diffusing down to the bottom interface and impacting on the rectifying behavior of the Schottky-like junction. Noteworthy, this asymmetric conduction can reflect in an asymmetric piezoelectric and ferroelectric behavior, as a sizable portion of the applied voltage drops across the rectifying junction in reverse bias, thus hampering symmetric bipolar operation, especially in leaky materials

La disfagia nell\u2019Ictus: analisi della nostra esperienza clinica.

La disfagia orofaringea, intesa come difficolt\ue0 del passaggio del bolo alimentare nelle strutture oro-faringee, ha un incidenza tra il 30-47% nei pazienti affetti da esiti di ictus cerebrale (Finestone, 2000; Burlato et al., 2003).Essa \ue8 pi\uf9 frequente nella prima settimana dopo l\u2019evento ictale (29%-64%), e la sua incidenza diminuisce progressivamente nella seconda-terza settimana (47%) per ridursi al 17% a due-quattro mesi dall\u2019evento acuto (Maronian N et al., 2003). Le complicanze pi\uf9 usuali a cui possono andare incontro i pazienti con disfagia sono la disidratazione, la malnutrizione e la polmonite da aspirazione (Westergren et al., 2001). Tali complicanze possono ostacolare i tempi e la qualit\ue0 del recupero funzionale e motorio dei pazienti. Ne consegue l\u2019importanza di una valutazione clinico-strumentale precoce (gi\ue0 in fase sub-acuta) da parte di un\u2019equipe multiprofessionale, al fine di prevenire le possibili complicanze e garantire una migliore prognosi. Lo scopo del nostro studio \ue8 stato quello di valutare l\u2019effetto del trattamento riabilitativo precoce sull\u2019outcome di un gruppo di pazienti disfagici secondariamente ad ictus

Acknowledgement to reviewers of JSAN in 2016

The editors of JSAN would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2016.[...

A Soluble Form of the High Affinity IgE Receptor, Fc-Epsilon-RI, Circulates in Human Serum

Soluble IgE receptors are potential in vivo modulators of IgE-mediated immune responses and are thus important for our basic understanding of allergic responses. We here characterize a novel soluble version of the IgE-binding alpha-chain of Fc-epsilon-RI (sFcεRI), the high affinity receptor for IgE. sFcεRI immunoprecipitates as a protein of ∼40 kDa and contains an intact IgE-binding site. In human serum, sFcεRI is found as a soluble free IgE receptor as well as a complex with IgE. Using a newly established ELISA, we show that serum sFcεRI levels correlate with serum IgE in patients with elevated IgE. We also show that serum of individuals with normal IgE levels can be found to contain high levels of sFcεRI. After IgE-antigen-mediated crosslinking of surface FcεRI, we detect sFcεRI in the exosome-depleted, soluble fraction of cell culture supernatants. We further show that sFcεRI can block binding of IgE to FcεRI expressed at the cell surface. In summary, we here describe the alpha-chain of FcεRI as a circulating soluble IgE receptor isoform in human serum