Different domains cooperate to target the human ribosomal L7a protein to the nucleus and to the nucleoli.

The human ribosomal protein L7a is a component of the major ribosomal subunit. We transiently expressed in HeLa cells L7a-β-galactosidase fusion proteins and studied their subcellular localization by indirect immunofluorescence staining with anti-β-galactosidase antibodies. We have identified three distinct domains responsible for the nuclear targeting of the protein: domain I, amino acids 23-51; domain II, amino acids 52-100; domain III, amino acids 101-220, each of which contains at least one nuclear localization signal (NLS). Through subcellular localization analysis of deletion mutants of L7a-β-galactosidase chimeras, we demonstrate that domain II plays a special role because it is necessary, although not sufficient, to target the chimeric β-galactosidase to the nucleoli. In fact, we demonstrate that the nucleolar targeting process requires the presence of domain II plus an additional basic domain that can be represented by an NLS or a basic stretch of amino acids without NLS activity. Thus, when multiple NLS are present, each NLS exerts distinct functions. Domain II drives nucleolar accumulation of a reporter protein with the cooperative action of a short basic amino acid sequence, suggesting a mechanism requiring protein-protein or protein-nucleic acid interactions

Further developments and tests of microstrip gas counters with resistive electrodes

We present results from further tests of Microstrip Gas Counters (MSGCs) with resistive electrodes. The maim advantage of this detector is that it is spark-protected: in contrast to "classical" MSGCs with metallic electrodes, sparks in this new detector do not destroy its electrodes. As a consequence the MSGC with resistive electrodes is more reliable in operation which may open new avenues in applications. One of them which is under investigation now is the use of Resistive electrodes MSGC (R-MSGC) as photodetector in some particular designs of noble liquid dark matter detectors.Comment: Presented at the RD-51 mini-week at CERN, January 17, 201

First Tests of Gaseous Detectors Made of a Resistive Mesh

We describe here various detectors designs: GEM type, MICROMEGAStype, PPACtype as well as cascaded detectors made of a resistive mesh manufactured from a resistive Kapton foil, (20 microns thick, resistivity a few MOhm per square) by a laser drilling technique. As in any other micropattern detectors the maximum achievable gas gain of these detectors is restricted by the Raether limit, however, the resistive mesh makes them and the front end electronics fully spark protected. This approach could be an alternative or complimentary to the ongoing efforts in developing MICROMEGAS and GEMs with resistive anode readout plates and can be especially beneficial in the case of micropattern detectors combined with a micropixel-type integrated front end electronic

An improved design of spark-protected microstrip gas counters (R-MSGC)

We have developed microstrip gas counters manufactured on standard printed circuit board and having the following features: resistive cathode strips, thin (10 micron) metallic anode strips and electrodes protected against surface discharges by a Coverlay layer at their edges. These features allow the detector to operate at gas gains as high as can be achieve with the best microstrip gas counters manufactured on glass substrates. We believe that after further developments this type of detectors can compete in some applications with other micropattern detectors, for example MICROMEGAS.Comment: Presented at the 7th RD51 Collaboration meeting, CERN, April 201

JP3D compression of solar data-cubes: photospheric imaging and spectropolarimetry

Hyperspectral imaging is an ubiquitous technique in solar physics observations and the recent advances in solar instrumentation enabled us to acquire and record data at an unprecedented rate. The huge amount of data which will be archived in the upcoming solar observatories press us to compress the data in order to reduce the storage space and transfer times. The correlation present over all dimensions, spatial, temporal and spectral, of solar data-sets suggests the use of a 3D base wavelet decomposition, to achieve higher compression rates. In this work, we evaluate the performance of the recent JPEG2000 Part 10 standard, known as JP3D, for the lossless compression of several types of solar data-cubes. We explore the differences in: a) The compressibility of broad-band or narrow-band time-sequence; I or V stokes profiles in spectropolarimetric data-sets; b) Compressing data in [x,y,$\lambda$] packages at different times or data in [x,y,t] packages of different wavelength; c) Compressing a single large data-cube or several smaller data-cubes; d) Compressing data which is under-sampled or super-sampled with respect to the diffraction cut-off

Progetto del nuovo Istituto Professionale a Castelnuovo Garfagnana

Con la presente Tesi ho affrontato la progettazione preliminare del nuovo Istituto Professionale a Castelnuovo Garfagnana previsto in località “La Saiona” e la riqualificazione dell’intera area che attualmente ospita il Liceo Scientifico “Galileo Galilei”, l’Istituto Tecnico Commerciale e per Geometri “Luigi Campedelli” e la palestra di recente costruzione. Lo studio effettuato è iniziato con una fase preliminare di apprendimento sull’edilizia scolastica, sulla sua nascita e il suo sviluppo attraverso i secoli, e si è protratto con la stesura del “Documento Preliminare all’avvio della Progettazione” (DPP) in linea con ciò che richiede il nuovo ordinamento in materia di Lavori Pubblici, che comprende: obiettivi e finalità della ricerca, vincoli, prestazioni attese, classi di esigenze da soddisfare connesse ai vincoli ed alle risorse per produrre e gestire nella vita utile ipotizzata dell’edificio. Il DPP ha rappresentato dunque una linea guida ed una messa a punto di tutto ciò che è servito per la progettazione del nuovo edificio, per verificarne la completezza e la funzionalità. Viene infine proposta una soluzione per il progetto preliminare attraverso elaborati grafici

Possible, alternative explanations of the T2K observation of the nu_e appearance from an initial nu_mu

An alternative explanation to the emergence of sin^2(2 theta_13) > 0 is discussed. It is pointed out that the recorded T2K events might have been due to some other new physics in the neutrino sector, related to the LSND/MiniBooNE sterile neutrino anomalies, for which there is nowadays a growing evidence. The presently running ICARUS detector with the CNGS beam will be able to distinguish between these two possible sources of the effectComment: 5 pages, 1 figur

On particle production for high energy neutrino beams

Analytical formulae for the calculation of secondary particle yields in p-A interactions are given. These formulae can be of great practical importance for fast calculations of neutrino fluxes and for designing new neutrino beam-lines. The formulae are based on a parameterization of the inclusive invariant cross sections for secondary particle production measured in p-Be interactions. Data collected in different energy ranges and kinematic regions are used. The accuracy of the fit to the data with the empirical formulae adopted is within the experimental uncertainties. Prescriptions to extrapolate this parameterization to finite targets and to targets of different materials are given. The results obtained are then used as an input for the simulation of neutrino beams. We show that our approach describes well the main characteristics of measured neutrino spectra at CERN. Thus it may be used in fast simulations aiming at the optimisation of the proposed long-baseline neutrino beams at CERN and FNAL. In particular we will show our predictions for the CNGS beam from CERN to Gran Sasso.Comment: 18 pages, 10 figures. Submitted to The European Physics Journal

Canonical formalism for compact sources

This thesis aims to describe the ADM formalism of General Relativity and to use the latter to describe a spherical compact source consisting of a perfect fluid. With two different choices for three-dimensional metric on hypersurfaces, we analyze the constraints of the system in the non-static case and the resulting equations of motion, both for canonical gravitational variables and those of matter. After examining some special cases, we also show that it is possible, in the case of static nature, to obtain the value of the Misner-Sharp mass from the Hamiltonian constraint, while near the trapping surfaces we obtain a relationship between the density of matter and the dynamic variables of the metric. Finally we propose a possible method for quantizing the constraints using the procedure that in the vacuum leads to the Wheeler-DeWitt equations

cis-acting sequences and trans-acting factors in the localization of mRNA for mitochondrial ribosomal proteins

mRNA localization is a conserved post-transcriptional process crucial for a variety of systems. Although several mechanisms have been identified, emerging evidence suggests that most transcripts reach the protein functional site by moving along cytoskeleton elements. We demonstrated previously that mRNA for mitochondrial ribosomal proteins are asymmetrically distributed in the cytoplasm, and that localization in the proximity of mitochondria is mediated by the 3′-UTR. Here we show by biochemical analysis that these mRNA transcripts are associated with the cytoskeleton through the microtubule network. Cytoskeleton association is functional for their intracellular localization near the mitochondrion, and the 3′-UTR is involved in this cytoskeleton-dependent localization. To identify the minimal elements required for localization, we generated DNA constructs containing, downstream from the GFP gene, deletion mutants of mitochondrial ribosomal protein S12 3′-UTR, and expressed them in HeLa cells. RT-PCR analysis showed that the localization signals responsible for mRNA localization are located in the first 154 nucleotides. RNA pulldown assays, mass spectrometry, and RNP immunoprecipitation assay experiments, demonstrated that mitochondrial ribosomal protein S12 3′-UTR interacts specifically with TRAP1 (tumor necrosis factor receptor-associated protein1), hnRNPM4 (heterogeneous nuclear ribonucleoprotein M4), Hsp70 and Hsp60 (heat shock proteins 70 and 60), and α-tubulin in vitro and in vivo