121 research outputs found

    Minimum centroid neighborhood for minimum zone sphericity

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    The minimum zone sphericity tolerance is derived from the ANSI and ISO standards for roundness and has extensive applications in the tribology of ball bearings, hip joints and other lubricated pairs. The worst-case proposed in this paper provides theoretical evidence that the minimum zone center of the two (circumscribed and inscribed reference) spheres with minimum radial separation containing the sampled spherical surface is included in a spherical neighborhood centered in the centroid of radius 2π-2EC, where EC is the sphericity error related to the centroid, which can be determined in closed form. Such linear estimating (about 20% of EC from the centroid, i.e., about one order of magnitude lower than the sphericity tolerance to be assessed) can be used to locate the sphere center with a given tolerance and as a search neighborhood for minimum zone center-based algorithms, such as metaheuristics (genetic algorithms, particle swarm optimization, etc.). The proposed upper bound has been experimentally assessed, using a genetic algorithm (GA) with parameters previously optimized for roundness and extended to three dimensions, which has overcome most of all available datasets from the literature that have been tested with center-based minimum zone algorithms by different authors. The optimum dataset size on artificially generated datasets is also discussed and it is speculated to allow the extension of the proposed upper bound to partial (or incomplete) spherical features

    Radiation test and application of FPGAs in the ATLAS Level 1 Trigger

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    The front-end system of the Silicon Drift Detectors (SDDs) of the ALICE experiment is made of two ASICs. The first chip performs the preamplification, temporary analogue storage and analogue-to-digital conversion of the detector signals. The second chip is a digital buffer that allows for a significant reduction of the connection from the front-end module to the outside world. In this paper, the results achieved on the first complete prototype of the front-end system for the SDDs of ALICE are presented

    A LYSO Calorimeter for the SuperB Factory

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    The SuperB project is an asymmetric e+e? accelerator of 1036cm?2s?1 luminosity, capable of collecting a data sample of 50?75 ab?1 in five years of running. The SuperB electromagnetic calorimeter (EMC), that will be described in this paper, provides energy and direction measurement of photons and electrons, and is used for identification of electrons versus other charged particles. In particular we will present its design, geometry study and related simulations, as well as R&D on LYSO crystals, a project for the mechanical structure and development on readout and electronics. A matrix of 6 crystals has been tested this year June 2010 at the Beam Test Facility of Frascati (BTF) at energies between 200 MeV and 500 MeV, and a beam test with the complete prototype of 25 crystals is foreseen at CERN in October 2010 to cover the energy range between 500 MeV and 7 GeV

    Transmembrane protein TMEM230, regulator of metalloproteins and motor proteins in gliomas and gliosis

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    Glial cells provide physical and chemical support and protection for neurons and for the extracellular compartments of neural tissue through secretion of soluble factors, insoluble scaffolds, and vesicles. Additionally, glial cells have regenerative capacity by remodeling their physical microenvironment and changing physiological properties of diverse cell types in their proximity. Various types of aberrant glial and macrophage cells are associated with human diseases, disorders, and malignancy. We previously demonstrated that transmembrane protein, TMEM230 has tissue revascularization and regenerating capacity by its ability to secrete pro-angiogenic factors and metalloproteinases, inducing endothelial cell sprouting and channel formation. In healthy normal neural tissue, TMEM230 is predominantly expressed in glial and marcophate cells, suggesting a prominent role in neural tissue homeostasis. TMEM230 regulation of the endomembrane system was supported by co-expression with RNASET2 (lysosome, mitochondria, and vesicles) and STEAP family members (Golgi complex). Intracellular trafficking and extracellular secretion of glial cellular components are associated with endocytosis, exocytosis and phagocytosis mediated by motor proteins. Trafficked components include metalloproteins, metalloproteinases, glycans, and glycoconjugate processing and digesting enzymes that function in phagosomes and vesicles to regulate normal neural tissue microenvironment, homeostasis, stress response, and repair following neural tissue injury or degeneration. Aberrantly high sustained levels TMEM230 promotes metalloprotein expression, trafficking and secretion which contribute to tumor associated infiltration and hypervascularization of high tumor grade gliomas. Following injury of the central nervous or peripheral systems, transcient regulated upregulation of TMEM230 promotes tissue wound healing, remodeling and revascularization by activating glial and macrophage generated microchannels/microtubules (referred to as vascular mimicry) and blood vessel sprouting and branching. Our results support that TMEM230 may act as a master regulator of motor protein mediated trafficking and compartmentalization of a large class of metalloproteins in gliomas and gliosis

    Normalisation of cerebrospinal fluid biomarkers parallels improvement of neurological symptoms following HAART in HIV dementia – case report

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    BACKGROUND: Since the introduction of HAART the incidence of HIV dementia has declined and HAART seems to improve neurocognitive function in patients with HIV dementia. Currently, HIV dementia develops mainly in patients without effective treatment, though it has also been described in patients on HAART and milder HIV-associated neuropsychological impairment is still frequent among HIV-1 infected patients regardless of HAART. Elevated cerebrospinal fluid (CSF) levels of markers of neural injury and immune activation have been found in HIV dementia, but neither of those, nor CSF HIV-1 RNA levels have been proven useful as diagnostic or prognostic pseudomarkers in HIV dementia. CASE PRESENTATION: We report a case of HIV dementia (MSK stage 3) in a 57 year old antiretroviral naĂŻve man who was introduced on zidovudine, lamivudine and ritonavir boosted indinavir, and followed with consecutive lumbar punctures before and after two and 15 months after initiation of HAART. Improvement of neurocognitive function was paralleled by normalisation of CSF neural markers (NFL, Tau and GFAP) levels and a decline in CSF and serum neopterin and CSF and plasma HIV-1 RNA levels. CONCLUSION: The value of these CSF markers as prognostic pseudomarkers of the effect of HAART on neurocognitive impairment in HIV dementia ought to be evaluated in longitudinal studies

    IL-7 Promotes CD95-Induced Apoptosis in B Cells via the IFN-Îł/STAT1 Pathway

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    Interleukin-7 (IL-7) concentrations are increased in the blood of CD4+ T cell depleted individuals, including HIV-1 infected patients. High IL-7 levels might stimulate T cell activation and, as we have shown earlier, IL-7 can prime resting T cell to CD95 induced apoptosis as well. HIV-1 infection leads to B cell abnormalities including increased apoptosis via the CD95 (Fas) death receptor pathway and loss of memory B cells. Peripheral B cells are not sensitive for IL-7, due to the lack of IL-7Ra expression on their surface; however, here we demonstrate that high IL-7 concentration can prime resting B cells to CD95-mediated apoptosis via an indirect mechanism. T cells cultured with IL-7 induced high CD95 expression on resting B cells together with an increased sensitivity to CD95 mediated apoptosis. As the mediator molecule responsible for B cell priming to CD95 mediated apoptosis we identified the cytokine IFN-Îł that T cells secreted in high amounts in response to IL-7. These results suggest that the lymphopenia induced cytokine IL-7 can contribute to the increased B cell apoptosis observed in HIV-1 infected individuals

    Postfordismo e trasformazione urbana.Casi di recupero dei vuoti industriali e indicazioni per le politiche nel territorio torinese

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    Il volume sulle aree dismesse e la trasformazione urbana promosso dalla Direzione Competitività della Regione Piemonte e dall'ente strumentale di ricerca economica e sociale, IRES Piemonte, racchiude contributi su esperienze di recupero dei vuoti urbani industriali e casi rilevanti della trasformazione urbana che hanno interessato Torino e la sua area metropolitana.- Prefazione #7- Introduzione #9- 1. Le ristrutturazioni industriali e il territorio: crisi, declino,metamorfosi? #33- 2. Scoprire i vuoti industriali: analisi e riflessioni a partire da censimenti e mappature di aree industriali dismesse a Torino #51- 3. Le aree dismesse nella riqualificazione e nella rigenerazione urbana a Torino (1990-2015) #113- 4. La trasformazione urbana tra grandi interventi e architetture “ordinarie”. #147- 5. Due esperienze di rigenerazione urbana sul territorio torinese:il Comitato Parco Dora sulla Spina 3 e il Comitato Urban in Barriera di Milano, a Torino #169- 6. Da cittadella industriale a Spina 3: una riconversione incompiuta #193- 7. Ex Diatto - Ex Westinghouse, due casi emblematici per le politiche di rivitalizzazione delle aree industriali torinesi #211- 8. Mirafiori. Dalla componentistica allo yogurt: storia di un progetto di re-industrializzazione #229- 9. Area OSI OVEST-NORD: Toolbox Coworking! #247- 10. Abilitare il territorio metropolitano alla rigenerazione e ad un nuovo sviluppo. Il caso di None, dall'industria subita all'industria inseguita #275- 11. Le ex-Acciaierie Mandelli di Collegno: la storia di una fabbrica,l'attualità del dibattito urbanistico. #301- 12. I programmi territoriali quale motore di rigenerazione urbana e di politiche di contenimento del consumo di suolo nel comune di Settimo Torinese #323- 13. La Regione Piemonte e la sfida del contenimento del consumo di suolo e del riutilizzo delle aree dismesse #353- 14. Torino, la nascita della città postindustriale: quale bilancio? #365- 15. Valutare i rischi della riqualificazione urbanistica e ambientale delle aree industriali dismesse #381- 16. Le aree industriali dismesse e il loro impatto sulla salute: il ruolo dei cittadini e delle amministrazioni locali nell'identificazione dei problemi e delle possibili soluzioni. #405- 17. I giovani e la città che cambia. Nuovi passi e nuovi sguardi sulle tracce di un passato industriale #427- Elenco degli autori e delle autrici #44
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