Critical quench dynamics in confined systems

We analyze the coherent quantum evolution of a many-particle system after slowly sweeping a power-law confining potential. The amplitude of the confining potential is varied in time along a power-law ramp such that the many-particle system finally reaches or crosses a critical point. Under this protocol we derive general scaling laws for the density of excitations created during the non-adiabatic sweep of the confining potential. It is found that the mean excitation density follows an algebraic law as a function of the sweeping rate with an exponent that depends on the space-time properties of the potential. We confirm our scaling laws by first order adiabatic calculation and exact results on the Ising quantum chain with a varying transverse field.Comment: To appear in Phys. Rev. Let

Full counting statistics in the spin-1/2 Heisenberg XXZ chain

The spin-1/2 Heisenberg chain exhibits a quantum critical regime characterized by quasi long-range magnetic order at zero temperature. We quantify the strength of quantum fluctuations in the ground state by determining the probability distributions of the components of the (staggered) subsystem magnetization. Some of these exhibit scaling and the corresponding universal scaling functions can be determined by free fermion methods and by exploiting a relation with the boundary sine-Gordon model

Full counting statistics in the gapped XXZ spin chain

We exploit the knowledge of the entanglement spectrum in the ground state of the gapped XXZ spin chain to derive asymptotic exact results for the full counting statistics of the transverse magnetisation in a large spin block of length \u2113. We found that for a subsystem of even length the full counting statistics is Gaussian, while for odd subsystems it is the sum of two Gaussian distributions. We test our analytic predictions with accurate tensor networks simulations. As a byproduct, we also obtain the symmetry (magnetisation) resolved entanglement entropies

Active shape correction of a thin glass/plastic X-ray mirror

Optics for future X-ray telescopes will be characterized by very large aperture and focal length, and will be made of lightweight materials like glass or plastic in order to keep the total mass within acceptable limits. Optics based on thin slumped glass foils are currently in use in the NuSTAR telescope and are being developed at various institutes like INAF/OAB, aiming at improving the angular resolution to a few arcsec HEW. Another possibility would be the use of thin plastic foils, being developed at SAO and the Palermo University. Even if relevant progresses in the achieved angular resolution were recently made, a viable possibility to further improve the mirror figure would be the application of piezoelectric actuators onto the non-optical side of the mirrors. In fact, thin mirrors are prone to deform, so they require a careful integration to avoid deformations and even correct forming errors. This however offers the possibility to actively correct the residual deformation. Even if other groups are already at work on this idea, we are pursuing the concept of active integration of thin glass or plastic foils with piezoelectric patches, fed by voltages driven by the feedback provided by X-rays, in intra-focal setup at the XACT facility at INAF/OAPA. In this work, we show the preliminary simulations and the first steps taken in this project

Characterization of the terminal column of TRIGA Mark II reactor of Mainz through of alanine pellets.

We have studied the ESR response of alanine pellets with and without gadolinium exposed to the thermal column of the TRIGA Mark II research reactor at the University of Mainz (Germany). The choice of Gd as additive nucleus is due to its very high capture cross section to thermal neutrons and to the possibility for secondary particles produced after interaction with thermal neutrons of releasing their energy in the neighborhood of the reaction site. In particular, it was found that low concentration (5% by weight) of Gd brings about a neutron sensitivity enhancement of more than 10 times without heavily reducing tissue equivalence. Monte Carlo (MC) simulations of both response of alanine and Gd-alanine pellets with FLUKA code were performed and the results were compared with the experimental values

Atti del Workshop: Tecniche Speciali e Avanzate di Dosimetria e Radioprotezione

Atti del Workshop organizzato dall'Associazione Italiana di Radioprotezione (AIRP) in collaborazione con l'Università degli Studi di Palermo, dal titolo "Tecniche Speciali e Avanzate in Dosimetria e Radioprotezione" che si svolgerà venerdì 24 Giugno a Palermo presso l'Aula Magna del Dipartimento di Fisica e Chimica, Viale delle Scienze Edificio 18. L'evento rientra tra i 210 Eventi organizzati per i 210 anni dalla fondazione dell'Ateneo palermitano su iniziativa del Magnifico Rettore, Prof. Fabrizio Micari. L’evento prevede la discussione di 4 tematiche in ambito della dosimetria e della radioprotezione in campo sanitario ed ambientale (Dosimetria Clinica, Dosimetria Ambientale, Dosimetria Retrospettiva e Tecniche Dosimetriche avanzate in Radioprotezione) ciascuna delle quali ha una relazione generale ad invito e alcune brevi comunicazioni orali. Le sessioni sono moderate da Dirigenti Fisici medici di due delle più importanti Aziende Ospedaliere Siciliane, Dirigenti dell’Istituto Superiore di Sanità e l’ex Rettore dell’Ateneo e membro del CdA del CNR, il Prof. Roberto Lagalla. Interverranno il magnifico Rettore dell’Università di Palermo, l’Assessore alla Sanità della Regione Sicilia, il Direttore dell’Istituto Zooprofilattico Sperimentale di Sicilia, il Direttore Generale dell’Agenzia per la Protezione dell’Ambiente Sicilia, il Direttore del Dipartimento di Fisica e Chimica, il Direttore di ATeN Center (Advanced Technologies Network), Dirigenti Fisici dell’Istituto Superiore di Sanità e dell’Istituto Europeo Oncologico di Milano. Hanno contribuito alla parte organizzativa e scientifica Dirigenti dell’ARPA Sicilia, Dirigenti dell’ARNAS Civico di Palermo, Docenti dell’Università di Palermo e di Milano, Ricercatori del CNR e Specializzandi UniPa. Questo evento è di grande rilevanza nazionale in termini di divulgazione scientifica vista la presenza dei relatori e moderatori invitati che ne danno lustro e rilevanza. Sarà un'occasione di confronto e di analisi retrospettiva a quarant'anni della giornata di studio “Problemi e prospettive della Fisica Sanitaria nel settore medico” organizzata dalla Prof.ssa Maria Brai

Establishment of Innovative Shared Departments to Advance Interdisciplinary Education

More and more universities are pursuing interdisciplinary academic activities that span across department and college boundaries. Administrative structures to facilitate such programs are difficult to establish within traditional university frameworks consisting of disciplinary departments and colleges. Often interdisciplinary programs are housed in a traditional disciplinary department or college, or in a standalone center reporting to a college dean or the provost. The difficulty of these structures is obtaining broad buy-in from faculty across departments and having disciplinary degree programs include interdisciplinary coursework. To overcome the difficulties described above, an innovative shared department structure that fosters collaborations to advance interdisciplinary education has been deployed at the University of New Haven. Three shared departments have been established over the last two years: (1) a college-wide department to support interdisciplinary coursework in the first two years of engineering programs; (2) a university-wide department to support entrepreneurship and innovation; and (3) a university-wide department to support health sciences. The shared departments typically have faculty whose tenure home is a traditional disciplinary department. Faculty membership is based on interest and activity level in teaching interdisciplinary courses, participating in interdisciplinary co-curricular activities, and performing interdisciplinary research. A few faculty members may be appointed full-time in a shared department. Like traditional departments, the shared departments have chairs to lead and coordinate activities. Faculty membership can vary from year-to-year depending on their level of activity in the shared department. The shared departments are responsible for approving interdisciplinary courses within their jurisdiction. The chairs of the departments are responsible for reviewing the performance of instructors teaching the interdisciplinary courses, and for providing feedback to disciplinary department chairs on the performance of faculty who are members of the shared department. To date the shared departments have facilitated the following: (1) an Entrepreneurial Engineering Living-Learning Community (LLC) for freshmen; (2) an Innovation and Entrepreneurship LLC for sophomores; (3) an integrated technical communications program across all engineering and computer science programs; (4) an integrated approach to developing entrepreneurial thinking in students across all engineering and computer science programs; (5) the development and teaching of courses on entrepreneurship; and (6) startup weekends and a business plan competition with students drawn from across the university. The detailed structure of the two shared departments and the lessons learned in establishing and operating them is described in this paper

ADIPONECTIN, LEPTIN, RESISTIN LEVELS IN CYSTIC FIBROSIS ADOLESCENTS

INTRODUCTION: Patients with Cystic Fibrosis, especially in adolescence, could develop endocrine and metabolic complications, related to nutritional state and chronic inflammation. They develop a progressive decrease in lean body mass correlated with the progression of lung disease. Adipose tissue is involved as well and adipocytokines are a possible link between malnutrition and long term complications. PATIENTS AND METHODS: In 24 Cystic Fibrosis adolescents we studied auxological, nutritional, glycometabolic, endocrine patterns, together with leptin, adiponectin and resistin levels. We selected patients not affected by diabetes, insulin resistance, malnutrition, acute inflammatory states so as to avoid possible influences on the adipocytokines. RESULTS: All patients presented with an adequate BMI centile, with no statistically significant difference versus controls. HOMA IR and HOMA B% are in the normal range but lower than in controls, expression of a lower insulin-resistance with a lower insulin secretion. Leptin is significantly higher than in controls and maintains a correlation with BMI and gender. Resistin levels are more elevated in Cystic Fibrosis than in controls, with a statistically significant direct correlation with CRP (C-reactive protein) and insulinemia T0\u2019 and T120\u2019.Adiponectin is significantly higher in Cystic Fibrosis, inversely correlated with CRP and insulinemia and directly with cholesterol and HDL-cholesterol. CONCLUSIONS:The detection of adipocytokines levels could improve the metabolic follow-up of these patients: the maintenance of an adequate leptin gender difference is useful in the follow-up of puberty in adolescence. Adiponectin could be a marker of insulin sensitivity and prevent protein catabolism and loss of lean body mass. Resistin levels may be used as a marker of insulin resistance and may indicate the severity of chronic inflammation. This is the first study available in literature about adiponectin levels in pediatric Cystic Fibrosis patients and about resistin in Cystic Fibrosis

X-raying hot plasma in solar active regions with the SphinX spectrometer

The detection of very hot plasma in the quiescent corona is important for diagnosing heating mechanisms. The presence and the amount of such hot plasma is currently debated. The SphinX instrument on-board CORONAS-PHOTON mission is sensitive to X-ray emission well above 1 keV and provides the opportunity to detect the hot plasma component. We analyzed the X-ray spectra of the solar corona collected by the SphinX spectrometer in May 2009 (when two active regions were present). We modelled the spectrum extracted from the whole Sun over a time window of 17 days in the 1.34-7 keV energy band by adopting the latest release of the APED database. The SphinX broadband spectrum cannot be modelled by a single isothermal component of optically thin plasma and two components are necessary. In particular, the high statistics and the accurate calibration of the spectrometer allowed us to detect a very hot component at ~7 million K with an emission measure of ~2.7 x 10^44 cm^-3. The X-ray emission from the hot plasma dominates the solar X-ray spectrum above 4 keV. We checked that this hot component is invariably present both at high and low emission regimes, i.e. even excluding resolvable microflares. We also present and discuss a possible non-thermal origin (compatible with a weak contribution from thick-target bremsstrahlung) for this hard emission component. Our results support the nanoflare scenario and might confirm that a minor flaring activity is ever-present in the quiescent corona, as also inferred for the coronae of other stars.Comment: 6 pages, 5 figures. Accepted for publication in A&