No quantum gravity signature from the farthest quasars

Context: Strings and other alternative theories describing the quantum properties of space-time suggest that space-time could present a foamy structure and also that, in certain cases, quantum gravity (QG) may manifest at energies much below the Planck scale. One of the observable effects could be the degradation of the diffraction images of distant sources. Aims: We searched for this degradation effect, caused by QG fluctuations, in the light of the farthest quasars (QSOs) observed by the Hubble Space Telescope with the aim of setting new limits on the fluctuations of the space-time foam and QG models. Methods: We developed a software that estimates and compares the phase variation in the interference patterns of the high-redshift QSOs, taken from the snapshot survey of HST-SDSS, with those of stars that are expected to not be affected by QG effects. We used a two-parameter function to determine, for each test star and QSO, the maximum of the diffraction pattern and to calculate the Strehl ratio. Results: Our results go far beyond those already present in the literature. By adopting the most conservative approach where the correction terms, that describe the possibility for space-time fluctuations cumulating across long distances and partially compensate for the effects of the phase variations, are taken into account. We exclude the random walk model and most of the holographic models of the space-time foam. Without considering these correction terms, all the main QG scenarios are excluded. Finally, our results show the absence of any directional dependence of QG effects and the validity of the cosmological principle with an independent method; that is, viewed on a large scale, the properties of the Universe are the same for all observers, including the effects of space-time fluctuations.Comment: 5 pages 6 figure

A rr-mode in a magnetic rotating spherical layer: application to neutron stars

The impact of the combination of rotation and magnetic fields on oscillations of stellar fluids is still not well known theoretically. It mixes Alfv\'en and inertial waves. Neutron stars are a place where both effects may be at work. We wish to decipher the solution of this problem in the context of $r$-modes instability in neutron stars, as it appears when these modes are coupled to gravitational radiation. We consider a rotating spherical shell filled with a viscous fluid but of infinite electrical conductivity and analyze propagation of modal perturbations when a dipolar magnetic field is bathing the fluid layer. We perform an extensive numerical analysis and find that the $m=2$ $r$-mode oscillation is influenced by the magnetic field when the Lehnert number (ratio of Alfv\'en speed to rotation speed) exceeds a value proportional to the one-fourth power of the Ekman number (non-dimensional measure of viscosity). This scaling is interpreted as the coincidence of the width of internal shear layers of inertial modes and the wavelength of the Alfv\'en waves. Applied to the case of rotating magnetic neutron stars, we find that dipolar magnetic fields above $10^{14}$ G are necessary to perturb the $r$-modes instability.Comment: 9 pages, 6 figures, to appear in Monthly Notices of RA

Gravitational waves from single neutron stars: an advanced detector era survey

With the doors beginning to swing open on the new gravitational wave astronomy, this review provides an up-to-date survey of the most important physical mechanisms that could lead to emission of potentially detectable gravitational radiation from isolated and accreting neutron stars. In particular we discuss the gravitational wave-driven instability and asteroseismology formalism of the f- and r-modes, the different ways that a neutron star could form and sustain a non-axisymmetric quadrupolar "mountain" deformation, the excitation of oscillations during magnetar flares and the possible gravitational wave signature of pulsar glitches. We focus on progress made in the recent years in each topic, make a fresh assessment of the gravitational wave detectability of each mechanism and, finally, highlight key problems and desiderata for future work.Comment: 39 pages, 12 figures, 2 tables. Chapter of the book "Physics and Astrophysics of Neutron Stars", NewCompStar COST Action 1304. Minor corrections to match published versio

Enhancing spatial perception through sound: mapping human movements into MIDI

Gestural expressiveness plays a fundamental role in the interaction with people, environments, animals, things, and so on. Thus, several emerging application domains would exploit the interpretation of movements to support their critical designing processes. To this end, new forms to express the people’s perceptions could help their interpretation, like in the case of music. In this paper, we investigate the user’s perception associated with the interpretation of sounds by highlighting how sounds can be exploited for helping users in adapting to a specific environment. We present a novel algorithm for mapping human movements into MIDI music. The algorithm has been implemented in a system that integrates a module for real-time tracking of movements through a sample based synthesizer using different types of filters to modulate frequencies. The system has been evaluated through a user study, in which several users have participated in a room experience, yielding significant results about their perceptions with respect to the environment they were immersed

Perceiving space through sound: Mapping human movements into MIDI

Gestural expressiveness plays a fundamental role in the interaction with people, environments, animals, things, and so on. Thus, several emerging application domains would exploit the interpretation of movements to support their critical designing processes. To this end, new forms to express the people's perceptions could help their interpretation, like in the case of music. This paper presents a novel algorithm for mapping human movements into MIDI music. The algorithm has been implemented in a system that integrates a module for real-time tracking of movements through a sample-based synthesizer using different types of filters to modulate frequencies. The system has been evaluated through a user study, in which several users have participated to a room experience, yielding significant results about their perceptions with respect to the environment they were immersed

PLASMOCITOMA EXTRAMIDOLLARE NASOSINUSALE: APPROCCIO DIAGNOSTICO MULTIDISCIPLINARE

Il Plasmocitoma è una proliferazione di un singolo clone di plasmacellule. Può presentarsi come singola lesione ossea (<5%), o meno comunemente localizzarsi all’esterno del sistema scheletrico (plasmocitoma extramidollare-PEM). Il PEM rappresenta 1% dei tumori testa-collo. Il 78-80% di PEM si manifestano nella regione testa-collo (80% cavità nasosinusale). L’età media alla diagnosi è 55-60 anni; il rapporto M/F è 3:1. I sintomi più comuni sono ostruzione respiratoria nasale monolaterale, epistassi, rinorrea. La diagnosi si effettua mediante biopsia, aspirato midollare, esami di laboratorio, Tomografia Computerizzara (TC), Risonanza Magnetica (RM) e PET/TC. La diagnosi differenziale si pone con linfoma non-Hodgkin e malattie linfoproliferative. La radioterapia (RT) è il trattamento di scelta. Riportiamo il caso di un PEM nasosinusale radiotrattato. MATERIALI E METODI Uomo di 72 anni giungeva alla nostra osservazione con pregressa diagnosi di polipo antrocoanale lamentando ostruzione respiratoria nasale monolaterale e rinorrea sieroematica da 3 mesi. L’endoscopia nasale mostrava una massa molle, friabile e sanguinante occupante la cavità nasale destra (meato medio). La TC senza mdc evidenziava un tessuto molle coinvolgente i seni fronto-etmoido-mascellare e cavità nasale destra. La RM con mdc evidenziava una formazione ovoidale iperintensa in T1 e FLAIR, ed ipointensa in T2 nella coana nasale destra. Proteina di Bence-Jones, elettroforesi serica, aspirato midollare osseo e PET-TC erano negativi. L’esame istologico mostrava diffusa popolazione plasma-cellulare CD138+ e restrizione per le catene leggere delle Ig (Igk). Analisi citogenetica FISH dimostrava assenza di del(13q14.3), del(17p13.1), di t(11;14)(q13;q32) e t(4;14)(p16q32). Il paziente è stato indirizzato a valutazione oncoematologica. RISULTATI I dati clinico-strumentali deponevano per diagnosi di PEM nasosinusale. Il paziente praticava RT (> 40Gy) e successivo follow-up. CONCLUSIONI La presenza di neoformazione nasosinusale monolaterale impone un protocollo diagnostico rigoroso. L’endoscopia rappresenta il primo step seguito dall’imaging. Tuttavia TC e RM non sono esaustive nella diagnosi di natura e la biopsia rappresenta l’unica indagine dirimente. Sebbene il PEM sia estremamente raro lo Specialista ORL non può trascurare un approfondimento diagnostico multidisciplinare che veda coinvolto oncoematologo, patologo e radioterapista

L’IMPORTANZA DEL PATTERN IMMUNOISTOCHIMICO PER LA DIAGNOSI DIFFERENZIALE DI SARCOMA GRANULOCITICO.

Il sarcoma granulocitico (SG) è una rara (3%) manifestazione extramidollare della Leucemia Acuta Mieloide (LAM). Rapporto M:F 1.42:1, età media alla diagnosi 37. Può essere isolato (8-20%), svilupparsi nel contesto di LAM o esserne espressione di recidiva (2.5-9.1%) e secondario a disordini mieloproliferativi/mielodisplastici. La diagnosi si effettua mediante biopsia, aspirato midollare, esami di laboratorio, imaging e va integrata con immunoistochimica e citochimica. La radioterapia (RT) è il trattamento di scelta in forme isolate, la chemioterapia combinata (induzione e consolidamento) in forme sistemiche. Riportiamo una raro caso di SG rinofaringe in paziente con pregressa LAM. MATERIALI E METODI Donna di 53 anni, non fumatrice, anamnesi positiva per LAM in remissione completa dopo chemioterapia ad alte dosi e trapianto di cellule staminali autologhe, praticate 7 anni prima. La paziente lamentava ipoacusia soggettiva sinistra da 5 mesi. L’endoscopia nasale evidenziava una massa peritubarica sinistra. Assenza di linfonodi latero-cervicali. L’imaging (RM e PET-TC) orientava per neoformazione rinofaringe (6 x 3,5 cm), SUV 5.7, assenza di erosione ossea. La biopsia rinofaringea evidenziava presenza di cellule immature. Al pattern immunoistochimico forte positività per CD43, CD34 e CD99 e negatività per mieloperossidasi (MPO) e CD117; elevata attività proliferativa Ki67 (circa 40%). Aspirato midollare negativo. RISULTATI I dati clinico-strumentali suggerivano ipotesi di localizzazione secondaria da processo ematologico. L’indagine immunoistochimica orientava per SG scarsamente differenziato (MPO-). La paziente praticava RT e follow-up. CONCLUSIONI Il SG è un tumore solido maligno, extramidollare, composto da mieloblasti o cellule mieloidi immature a vario grado di differenziazione. Spesso, nei soggetti non leucemici, le forme scarsamente differenziate sono diagnosticate erroneamente come linfoma a grandi cellule/linfoblastico/Burkitt e carcinoma anaplastico. L’immunoistochimica è necessaria per la diagnosi di SG e va sempre programmata in caso di patologia espansiva rinofaringea soprattutto se sussiste anamnesi positiva per patologia linfoproliferativa, anche se pregressa. Il caso riportato MPO-, raro in letteratura, orienta per diagnosi di SG, scarsamente differenziato, dunque a prognosi peggiore. Per questo la paziente è entrata in un protocollo multidisciplinare di follow-up tipo “short time”

Sinonasal extramedullary plasmacytoma: a proposal of a new protocol of follow-up

We report the youngest (37y) case described in the literature. We describe the first case series of Plasmacytoma undergone robotic radiosurgery radiotherapy by CyberKnife… Although performed on a small number of patients, our observations suggest the possibility of long-term control of EMP and complete remission. We propose a new follow-up protocol consisting of - nasal endoscopy every 3 months - serum exams associated with imaging study (MRI) every 6 months after therapy for the first 5 years. Subsequently nasal endoscopy and MRI every year