335 research outputs found

    Rapid One-Step Fabrication of Graphene Oxide-Decorated Polycaprolactone Three-Dimensional Templates for Water Treatment

    Get PDF
    Coating of flexible substrates is crucial to prepare versatile, multifunctional materials. However, exploration of effective fabrication approaches is still a challenging issue, because the pathways generally proposed require time-consuming, multistep protocols. Here, we developed a one-pot process for decorating either pearl necklace-like or fibrous fluffy-like structures of polycaprolactone (PCL) with graphene oxide (GO) skin. PCL solutions were dry jet-wet electrosprayed or electrospun into a stirred liquid collector constituted by ethanol-containing GO nanoparticles. The stirred liquid collector enables the formation of 3D-structures, whose microarchitecture can be designed by controlling the rheological behavior of PCL solutions. Two molecular weights of PCL were used (45 or 80 kDa) with ensuing different viscosity, which determines the prevalent formation of beads or fibers. The presence of GO in the coagulation bath allows the polymeric structures to be rapidly wrapped by those nanoparticles. Graphenic coating endows these materials with the intriguing peculiarities of GO: PCL/GO nanocomposites displayed increments of elastic modulus ranging from 1250% (beads) to 3300% (fibers) with respect to the neat matrices and a change from hydrophobic to amphiphilic character. A potential application of such devices in water treatment was assessed in phenol removal. The results pointed out that PCL/GO scaffolds retain the same sorption capacity of GO nanoparticles, while bringing several advantages in terms of handling, robustness, and recyclability. The ease of control of the process, as well as its fastness and cost-effectiveness could open a wide range of scenarios, including sensors, energy, catalysis, biomedicine

    Improved Cu2O/AZO Heterojunction by Inserting a Thin ZnO Interlayer Grown by Pulsed Laser Deposition

    Get PDF
    Cu2O/ZnO:Al (AZO) and Cu2O/ZnO/AZO heterojunctions have been deposited on glass substrates by a unique three-step pulsed laser deposition process. The structural, optical, and electrical properties of the oxide films were investigated before their implementation in the final device. X-ray diffraction analysis indicated that the materials were highly crystallized along the c-axis. All films were highly transparent in the visible region with enhanced electrical properties. Atomic force and scanning electron microscopies showed that the insertion of a ZnO layer between the Cu2O and AZO films in the heterojunction enhanced the average grain size and surface roughness. The heterojunctions exhibited remarkable diode behavior and good rectifying character with low leakage current under reverse bias. The presence of the ZnO interlayer film significantly reduced the parasitic and leakage currents across the barrier, improved the quality of the heterostructure, made the energy band between AZO and Cu2O layers smoother, and eliminated the possibility of interface recombination, leading to much longer electron lifetime

    Channeler Ant Model: 3D segmentation of medical images through ant colonies

    Get PDF
    In this paper the Channeler Ant Model (CAM) and some results of its applications to the analysis of medical images are described. The CAM is an algorithm able to segment 3D structures with different shapes, intensity and background. It makes use of virtual ant colonies and exploits their natural capabilities to modify the environment and communicate with each other by pheromone deposition. Its performance has been validated with the segmentation of 3D artificial objects and it has been already used successfully in lung nodules detection on Computer Tomography images. This work tries to evaluate the CAM as a candidate to solve the quantitative segmentation problem in Magnetic Resonance brain images: to evaluate the percentage of white matter, gray matter and cerebrospinal fluid in each voxel

    Restoration of a XVII century’s predella reliquary: From physico-chemical characterization to the conservation process

    Get PDF
    We report on the restoration of a XVII century’s predella reliquary, which is a part of a larger setup that includes a wall reliquary and a wooden crucified Christ, both belonging to the church of “Madre Maria SS. Assunta”, in Polizzi Generosa, Sicily, Italy. The historical/artistic and paleographic research was flanked successfully by the scientific objective characterization of the materials. The scientific approach was relevant in the definition of the steps for the restoration of the artefact. The optical microscopy was used for the identification of the wood species. Electron microscopy and elemental mapping by energy-dispersive X-ray (EDX) was successful in the identification of the layered structure for the gilded surface. The hyperspectral imaging method was successfully employed for an objective chemical mapping of the surface composition. We proved that the scientific approach is necessary for a critical and objective evaluation of the conservation state and it is a necessary step toward awareness of the historical, liturgical, spiritual and artistic value. In the second part of this work, we briefly describe the conservation protocol and the use of a weak nanocomposite glue. In particular, a sustainable approach was considered and therefore mixtures of a biopolymer from natural resources, such as funori from algae, and naturally occurring halloysite nanotubes were considered. Tensile tests provided the best composition for this green nanocomposite glue

    Medial or Lateral, That Is the Question: A Retrospective Study to Compare Two Injection Techniques in the Treatment of Knee Osteoarthritis Pain with Hyaluronic Acid

    Get PDF
    Background: Mild-to-moderate knee osteoarthritis (KOA) can be successfully treated using intra-articular hyaluronic acid (IA-HA). The medial infrapatellar (MIP) approach and lateral infrapatellar (LIP) approach are two of the most used techniques for performing IA-HA, but it is still not clear which one is preferable. Objectives: The study aims to find the best knee injection technique between MIP and LIP approaches. Methods: In total, 161 patients were enrolled, divided into two groups (MIP or LIP). Each technique was performed once a week for three weeks. Patients were evaluated using the Numeric Rating Scale (NRS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Roles and Maudsley Score (RMS) at T0 (before the first injection), T1 (one week after the third injection) and T2 (six months after). Results: NRS, KOOS and RMS showed a statistically significant improvement in both groups at all the detection times, without significant differences. No differences were detected between the groups in terms of systemic effect effusions, while the MIP group presented a mildly higher number of bruises in comparison with the LIP group (p = 0.034). Conclusions: Both the IA-HA techniques are equally effective in measured outcomes. The MIP approach seems to produce some local and transient side effects. So, the choice of the LIP or MIP approach depends on the operator’s skill and experience

    NEMO: A Project for a km3^3 Underwater Detector for Astrophysical Neutrinos in the Mediterranean Sea

    Full text link
    The status of the project is described: the activity on long term characterization of water optical and oceanographic parameters at the Capo Passero site candidate for the Mediterranean km3^3 neutrino telescope; the feasibility study; the physics performances and underwater technology for the km3^3; the activity on NEMO Phase 1, a technological demonstrator that has been deployed at 2000 m depth 25 km offshore Catania; the realization of an underwater infrastructure at 3500 m depth at the candidate site (NEMO Phase 2).Comment: Proceeding of ISCRA 2006, Erice 20-27 June 200

    Analysis of the Autonomic Regulation in a Case of Facioscapulohumeral Muscular Dystrophy after Ken Ware Treatment

    Get PDF
    Abstract This is a study on autonomic neuroscience. In a previous paper in [1], we studied a subject affected from facioscapulohumeral muscular dystrophy before and after Ken Ware treatment (NPT). Using the non linear methodology of the Generalized Mutual Information (GMI) analysis of Sensory Motor Rhythm, we produced detailed results evidencing that the mentioned NPT treatment involved a net improvement of the patient under his subjective psychological condition, and in particular, under the neurological and sensory motor profile. We quantified with accuracy the improvement that the subject realized during such treatment. Of course, previous studies of several authors have evidenced that muscular dystrophies are strongly linked to a profound ANS disfunction. Therefore, the aim of the present study was to analyze the ANS of the subject before and after the treatment. We performed analysis in time as well as in frequency domain and by using non linear methods. The basic result of the paper was that, according to our analysis, the subjects started with a serious ANS disfunction before the NPT treatment and that a net improvement was obtained after this therapy. All the examined parameters resulted strongly altered before the treatment and all they returned in the normal range after the NPT

    Muon `Depth -- Intensity' Relation Measured by LVD Underground Experiment and Cosmic-Ray Muon Spectrum at Sea Level

    Get PDF
    We present the analysis of the muon events with all muon multiplicities collected during 21804 hours of operation of the first LVD tower. The measured angular distribution of muon intensity has been converted to the `depth -- vertical intensity' relation in the depth range from 3 to 12 km w.e.. The analysis of this relation allowed to derive the power index, γ\gamma, of the primary all-nucleon spectrum: γ=2.78±0.05\gamma=2.78 \pm 0.05. The `depth -- vertical intensity' relation has been converted to standard rock and the comparison with the data of other experiments has been done. We present also the derived vertical muon spectrum at sea level.Comment: 7 pages, 3 figures, to be published on Phys. Rev.
    • …
    corecore