3,183 research outputs found

    The Polito Surface Wave flat-file Database (PSWD): statistical properties of test results and some inter-method comparisons

    Get PDF
    The compilation and maintenance of experimental databases are of crucial importance in all research fields, allowing for researchers to develop and test new methodologies. In this work, we present a flat-file database of experimental dispersion curves and shear wave velocity profiles, mainly from active surface wave testing, but including also data from passive surface wave testing and invasive methods. The Polito Surface Wave flat-file Database (PSWD) is a gathering of experimental measurements collected within the past 25 years at different Italian sites. Discussion on the database content is reported in this paper to evaluate some statistical properties of surface wave test results. Comparisons with other methods for shear wave velocity measurements are also considered. The main novelty of this work is the homogeneity of the PSWD in terms of processing and interpretation methods. A common processing strategy and a new inversion approach were applied to all the data in the PSWD to guarantee consistency. The PSWD can be useful for further correlation studies and is made available as a reference benchmark for the validation and verification of novel interpretation procedures by other researchers

    Scanning Probe Microscopy for polymer film characterization in food packaging

    Get PDF
    Scanning probe microscopy (SPM) is a branch of microscopy allowing characterization of surfaces at the micro-scale by means of a physical probe (with a size of a few microns) raster scanning the sample. SPMs monitor the interaction between such probe and the surface and, depending on the specific physical principles causing the interaction, they allow generation of a quantitative map of topographic properties: geometrical, optical, electrical, magnetic, etc. This is of the greatest interest, in particular whenever functional surfaces have to be characterized in a quantitative manner. The present paper discusses the different applications of Scanning Probe Microscopy techniques for a thorough characterization of polymer surfaces, of specific interest in particular for the case of food packaging applications

    Scientific basis of nanotechnology, implications for the food sector and future trends

    Get PDF
    Nanotechnologies are opening up new horizons in almost all scientific and technological fields. Among these, applications of nanotechnologies are expected to bring large benefits and add value to the food and food-related industries through the current regulatory framework whole food chain, from production to processing, safety, packaging, transportation, storage and delivery. Nanotechnology consists in the realization and manipulation of nano-sized matter, the unique properties of which with respect to their bulk counterparts are illustrated and discussed. Then, the main tools and techniques routinely used in nanotechnology for the nanoscale characterization of food matrices as well as for the analytical determination of nanomaterials in food samples are reviewed. Finally, safety and risk assessment issues are discussed and an overview of applications of nanotechnology to the food sector is provided along with a description of th

    Combined Bulk and Surface Radiation Damage Effects at Very High Fluences in Silicon Detectors: Measurements and TCAD Simulations

    Full text link
    In this work we propose a new combined TCAD radiation damage modelling scheme, featuring both bulk and surface radiation damage effects, for the analysis of silicon detectors aimed at the High Luminosity LHC. In particular, a surface damage model has been developed by introducing the relevant parameters (NOX, NIT) extracted from experimental measurements carried out on p-type substrate test structures after gamma irradiations at doses in the range 10-500 Mrad(Si). An extended bulk model, by considering impact ionization and deep-level cross-sections variation, was included as well. The model has been validated through the comparison of the simulation findings with experimental measurements carried out at very high fluences (2 10^16 1 MeV equivalent n/cm^2) thus fostering the application of this TCAD approach for the design and optimization of the new generation of silicon detectors to be used in future HEP experiments.Comment: 8 pages, 14 figures. arXiv admin note: text overlap with arXiv:1611.1013

    Study of MDT calibration constants using H8 testbeam data of year 2004

    Get PDF
    In year 2004 Atlas performed a long campaign of test beam data taking at the H8 Cern beam. Two sectors of the barrel and endcap regions of the Muon Spectrometer were exposed to the beam and large amount of data were collected in well defined and controlled operating conditions. This allowed a careful study on MDT drift properties. A better understanding of the calibration constants, of their definition and determination and of the criteria for their acceptance has been obtained. Systematic effects and time stability of the constants have also been studied

    Smart magnetic nanovesicles for theranostic application: Preparation and characterization

    Get PDF
    Nanomedicines are submicrometer-sized carrier materials designed to improve the biodistribution of systemically administered (chemo)therapeutic agents. By delivering pharmacologically active agents more effectively and more selectively to the pathological site nanomedicines aim to improve the balance between the efficacy and the toxicity of systemic (chemo)therapeutic administrations. Nanomedicine formulations have also been used for imaging applications and, in recent years, for theranostic approaches, that is, for systems and strategies in which disease diagnosis and therapy are combined. On the one hand, “classical” drug delivery systems are being co-loaded with both drugs and contrast agents. Actually, nanomaterials with an intrinsic ability to be used for imaging purposes, such as iron-oxide–based magnetic nanoparticles (MNPs), are increasingly being loaded with drugs or alone for combining disease diagnosis and therapy. In this study, non-ionic surfactant vesicles loaded with lipophilic and hydrophilic MNPs have been prepared. Vesicles have been characterized in terms of dimensions, ζ-potential, time stability, bilayer characteristics and overall iron content. The encouraging obtained results confirm that Tween 20 and Span 20 vesicles could be promising carriers for the delivery of hydrophilic and lipophilic MNPs, respectively, thereby prompting various opportunities for the development of suitable theranostic strategies. The analyzed formulations confirm the importance of surfactant chemical-physical characteristics in entrapping the MNPs of different polarity, highlighting the high versatility of niosomal bilayer and structure; property that make them so appealing among drug delivery nanocarriers

    Ten years of pluviometric analyses in Italy for civil protection purposes

    Get PDF
    The concept of climate change has grown in recent decades, influencing the scientific community to conduct research on meteorological parameters and their variabilities. Research on global warming, as well as on its possible economic and environmental consequences, has spread over the last 20 years. Diffused changes in trends have been stated by several authors throughout the world, with different developments observed depending on the continent. Following a period of approximately 40 days of almost continuous rain that occurred from October to November 2019 across the Italian territory and caused several hazards (e.g., floods and landslides), a relevant question for decision-makers and civil protection actors emerged regarding the relative frequencies of given rainfall events in the Warning Hazard Zones (WHZs) of Italy. The derived products of this work could answer this question for both weather and hydrogeological operators thanks to the frequency and spatio-temporal distribution analyses conducted on 10-year daily rainfall data over the entire Italian territory. This work aspires to be an additional tool used to analyse events that have occurred, providing further information for a better understanding of the probability of occurrence and distribution of future events

    CD200 as a Potential New Player in Inflammation during Rotator Cuff Tendon Injury/Repair: An In Vitro Model

    Get PDF
    Rotator cuff tendon (RCT) disease results from multifactorial mechanisms, in which inflammation plays a key role. Pro-inflammatory cytokines and tendon stem cell/progenitor cells (TSPCs) have been shown to participate in the inflammatory response. However, the underlying molecular mechanism is still not clear. In this study, flow cytometry analyses of different subpopulations of RCT-derived TSPCs demonstrate that after three days of administration, TNFα alone or in combination with IFNγ significantly decreases the percentage of CD146+CD49d+ and CD146+CD49f+ but not CD146+CD109+ TSPCs populations. In parallel, the same pro-inflammatory cytokines upregulate the expression of CD200 in the CD146+ TSPCs population. Additionally, the TNFα/IFNγ combination modulates the protein expression of STAT1, STAT3, and MMP9, but not fibromodulin. At the gene level, IRF1, CAAT (CAAT/EBPbeta), and DOK2 but not NF-κb, TGRF2 (TGFBR2), and RAS-GAP are modulated. In conclusion, although our study has several important limitations, the results highlight a new potential role of CD200 in regulating inflammation during tendon injuries. In addition, the genes analyzed here might be new potential players in the inflammatory response of TSPCs
    • …
    corecore