Self-attraction effect and correction on three absolute gravimeters

The perturbations of the gravitational field due to the mass distribution of an absolute gravimeter have been studied. The so called Self Attraction Effect (SAE) is crucial for the measurement accuracy, especially for the International Comparisons, and for the uncertainty budget evaluation. Three instruments have been analysed: MPG-2, FG5-238 and IMPG-02. The SAE has been calculated using a numerical method based on FEM simulation. The observed effect has been treated as an additional vertical gravity gradient. The correction (SAC) to be applied to the computed g value has been associated with the specific height level, where the measurement result is typically reported. The magnitude of the obtained corrections is of order 1E-8 m/s2.Comment: 14 pages, 8 figures, submitted to Metrologi

Il trattamento chirurgico dei tumori maligni del labbro. Esperienza personale

I tumori maligni del labbro rappresentano circa l’1-2% delle neoplasie cervico-facciali. Tali lesioni sono più frequentemente costi - tuite da carcinomi spinocellulari e basocellulari che nel complesso rappresentano il 25% di tutti i tumori orali. Mentre il carcinoma spinocellulare si localizza soprattutto sul labbro inferiore, il carcino - ma basocellulare si riscontra maggiormente sul labbro superiore .Il sesso maschile risulta essere sensibilmente il più colpito. L’etiopatoge - nesi di queste neoplasie è legata all’esposizione solare, al fumo, alla predisposizione genetica (mutazione del gene soppressore p53), all’e - voluzione di forme di precancerosi, quali radiodermiti, cheiliti croni - che, xeroderma pigmentosum. Inoltre, alcuni Autori enfatizzano il ruolo svolto da diversi agenti virali quali HPV16, HPV24, HSV1 e HSV2. Il trattamento dei carcinomi del labbro è prevalentemente chirurgico ed è fondamentalmente rappresentato dall’escissione della lesione e successiva ricostruzione del labbro. Le tecniche riparative sono numerose e per la maggior parte basate sull’utilizzo di lembi cutanei locali di scorrimento e di rotazione. La ricostruzione del lab - bro comporta un notevole impegno al fine di preservare quanto più possibile forma e funzioni essendo il labbro fondamentale nell’ali - mentazione, nella fonazione e nella mimica espressiva. Gli Autori riportano la loro esperienza riguardo il trattamento chi - rurgico di 19 pazienti, 17 di sesso maschile, di età compresa tra 58 e 84 anni (età media 72 anni), affetti da carcinoma del labbro (16 spi - nocellulari, 3 basocellulari) con prevalenza di forme ben differenziate. Vengono inoltre discusse le principali problematiche ricostruttive ine - renti la preservazione degli aspetti estetici e funzionali delle labbra

Magnetic Fluctuations and Turbulence in the Venus Magnetosheath and Wake

Recent research has shown that distinct physical regions in the Venusian induced magnetosphere are recognizable from the variations of strength and of wave/fluctuation activity of the magnetic field. In this paper the statistical properties of magnetic fluctuations are investigated in the Venusian magnetosheath, terminator, and wake regions. The latter two regions were not visited by previous missions. We found 1/f fluctuations in the magnetosheath, large-scale structures near the terminator and more developed turbulence further downstream in the wake. Location independent short-tailed non-Gaussian statistics was observed.Comment: 16 pages, 4 figure

Heteropolyacids supported on zirconia-doped γ, θ and α alumina: A physicochemical assessment and characterisation of supported solid acids

In this paper we carry out a surface study of promising supported solid acid catalysts commonly used for the production of high value chemicals derived from glycerol. In particular, γ, θ and α alumina (Al2O3) were modified by (i) grafting with 5 wt% zirconia, (ii) doping with 30 wt% silicotungstic acid (STA), and (iii) using both zirconia and STA. The aim is to rationalise the effect of these different parameters on structural properties and surface adsorption through a comprehensive multi-technique approach, including recently developed NMR relaxation techniques. XRD and laser Raman spectroscopy confirmed a strong interaction between STA and the γ-/θ-Al2O3 resulting in a distortion of the supported STA Keggin structure relative to that of bulk STA. Conversely, a much weaker interaction between the supported STA and α-Al2O3 was measured. NMR relaxation demonstrated that the STA doping increases the adsorption properties of the catalyst, particularly for γ-/θ-Al2O3. For catalysts based on α-Al2O3, such effect was negligible. Thermogravimetric/differential thermogravimetry (TGA/DTG) analysis suggested that zirconia-grafted and non-grafted θ-Al2O3 and γ-Al2O3 are suitable materials for increasing the thermal stability of STA whereas α-Al2O3 (both grafted and non-grafted) does not improve the thermal stability of STA

Quantum-enhanced sensing of axion dark matter with a transmon-based single microwave photon counter

We report an axion dark matter search with a haloscope equipped with a microwave photon counter. The haloscope is a tunable high quality factor 3-dimensional microwave cavity placed in a magnetic field. The photon counter, operated cyclically, maps an incoming microwave photon onto the state of a superconducting transmon qubit. The measurement protocol continuously monitors the power emitted by the haloscope cavity as well as the dark count background, and enables tuning of the cavity frequency to probe different axion masses. With this apparatus we enhance by a factor 20 the search speed that can be reached with quantum-limited linear amplifiers, and set a new standard for probing the existence of axions with resonant detectors

Mass and charge identification of fragments detected with the Chimera Silicon-CsI(Tl) telescopes

Mass and charge identification of charged products detected with Silicon-CsI(Tl) telescopes of the Chimera apparatus is presented. An identification function, based on the Bethe-Bloch formula, is used to fit empirical correlation between Delta E and E ADC readings, in order to determine, event by event, the atomic and mass numbers of the detected charged reaction products prior to energy calibration.Comment: 24 pages, 7 .jpg figures, submitted to Nucl.Instr.

Isotope correlations as a probe for freeze-out characterization: central 124Sn+64Ni, 112Sn+58Ni collisions

124Sn+64Ni and 112Sn+58Ni reactions at 35 AMeV incident energy were studied with the forward part of CHIMERA multi-detector. The most central collisions were selected by means of a multidimensional analysis. The characteristics of the source formed in the central collisions, as size, temperature and volume, were inspected. The measured isotopes of light fragments (3 <= Z <=8) were used to examine isotope yield ratios that provide information on the free neutron to proton densities.Comment: 4 pages, Contribution to 8th International Conference on Nucleus-Nucleus Collisions, Moscow 200