114 research outputs found

    In-doped Sb nanowires grown by MOCVD for high speed phase change memories

    Get PDF
    We investigated the Phase Change Memory (PCM) capabilities of In-doped Sb nanowires (NWs) with diameters of (20-40) nm, which were self-assembled by Metalorganic Chemical Vapor Deposition (MOCVD) via the vapor-liquid-solid (VLS) mechanism. The PCM behavior of the NWs was proved, and it was shown to have relatively low reset power consumption (~ 400 μW) and fast switching capabilities with respect to standard Ge-Sb-Te based devices. In particular, reversible set and reset switches by voltage pulses as short as 25 ns were demonstrated. The obtained results are useful for understanding the effects of downscaling in PCM devices and for the exploration of innovative PCM architectures and materials. Keywords: Phase change memories, Nanowires, MOCVD, In-Sb, TEM, XR

    In-doped Sb nanowires grown by MOCVD for high speed phase change memories

    Get PDF
    We investigated the Phase Change Memory (PCM) capabilities of In-doped Sb nanowires (NWs) with diameters of (20-40) nm, which were self-assembled by Metalorganic Chemical Vapor Deposition (MOCVD) via the vapor-liquid-solid (VLS) mechanism. The PCM behavior of the NWs was proved, and it was shown to have relatively low reset power consumption (~ 400 μW) and fast switching capabilities with respect to standard Ge-Sb-Te based devices. In particular, reversible set and reset switches by voltage pulses as short as 25 ns were demonstrated. The obtained results are useful for understanding the effects of downscaling in PCM devices and for the exploration of innovative PCM architectures and materials

    Protective Mechanical Ventilation during General Anesthesia for Open Abdominal Surgery Improves Postoperative Pulmonary Function

    Get PDF
    BACKGROUND:: The impact of intraoperative ventilation on postoperative pulmonary complications is not defined. The authors aimed at determining the effectiveness of protective mechanical ventilation during open abdominal surgery on a modified Clinical Pulmonary Infection Score as primary outcome and postoperative pulmonary function. METHODS:: Prospective randomized, open-label, clinical trial performed in 56 patients scheduled to undergo elective open abdominal surgery lasting more than 2 h. Patients were assigned by envelopes to mechanical ventilation with tidal volume of 9 ml/kg ideal body weight and zero-positive end-expiratory pressure (standard ventilation strategy) or tidal volumes of 7 ml/kg ideal body weight, 10 cm H2O positive end-expiratory pressure, and recruitment maneuvers (protective ventilation strategy). Modified Clinical Pulmonary Infection Score, gas exchange, and pulmonary functional tests were measured preoperatively, as well as at days 1, 3, and 5 after surgery. RESULTS:: Patients ventilated protectively showed better pulmonary functional tests up to day 5, fewer alterations on chest x-ray up to day 3 and higher arterial oxygenation in air at days 1, 3, and 5 (mmHg; mean \ub1 SD): 77.1 \ub1 13.0 versus 64.9 \ub1 11.3 (P = 0.0006), 80.5 \ub1 10.1 versus 69.7 \ub1 9.3 (P = 0.0002), and 82.1 \ub1 10.7 versus 78.5 \ub1 21.7 (P = 0.44) respectively. The modified Clinical Pulmonary Infection Score was lower in the protective ventilation strategy at days 1 and 3. The percentage of patients in hospital at day 28 after surgery was not different between groups (7 vs. 15% respectively, P = 0.42). CONCLUSION:: A protective ventilation strategy during abdominal surgery lasting more than 2 h improved respiratory function and reduced the modified Clinical Pulmonary Infection Score without affecting length of hospital stay

    Catastrophic NAD+ Depletion in Activated T Lymphocytes through Nampt Inhibition Reduces Demyelination and Disability in EAE

    Get PDF
    Nicotinamide phosphoribosyltransferase (Nampt) inhibitors such as FK866 are potent inhibitors of NAD+ synthesis that show promise for the treatment of different forms of cancer. Based on Nampt upregulation in activated T lymphocytes and on preliminary reports of lymphopenia in FK866 treated patients, we have investigated FK866 for its capacity to interfere with T lymphocyte function and survival. Intracellular pyridine nucleotides, ATP, mitochondrial function, viability, proliferation, activation markers and cytokine secretion were assessed in resting and in activated human T lymphocytes. In addition, we used experimental autoimmune encephalomyelitis (EAE) as a model of T-cell mediated autoimmune disease to assess FK866 efficacy in vivo. We show that activated, but not resting, T lymphocytes undergo massive NAD+ depletion upon FK866-mediated Nampt inhibition. As a consequence, impaired proliferation, reduced IFN-γ and TNF-α production, and finally autophagic cell demise result. We demonstrate that upregulation of the NAD+-degrading enzyme poly-(ADP-ribose)-polymerase (PARP) by activated T cells enhances their susceptibility to NAD+ depletion. In addition, we relate defective IFN-γ and TNF-α production in response to FK866 to impaired Sirt6 activity. Finally, we show that FK866 strikingly reduces the neurological damage and the clinical manifestations of EAE. In conclusion, Nampt inhibitors (and possibly Sirt6 inhibitors) could be used to modulate T cell-mediated immune responses and thereby be beneficial in immune-mediated disorders

    Advancing the global public health agenda for NAFLD: a consensus statement

    Get PDF

    An algebraic model for exchange organs

    No full text

    Morphoecology in larval fin-fish: A new candidate species for aquaculture, Diplodus puntazzo (Sparidae)

    No full text
    This study was aimed to acquire information on trophic behavior of Diplodus puntazzo larvae and juveniles, by studing the ontogenetic sensory development, except vision. D. puntazzo specimens were observed using a scanning electron (n = 67) and a light microscope (n = 7). The results concerned four ontogenetical stages of sharpsnout seabream: larval, post-larval, transitional, and juvenile stages. The yolk-sac larval stage was not detected as the smallest larvae at our disposal (3.1 mm TL; 2nd day from hatching) showed no external appearance of the yolk. During the larval stage (3.1–4.7 mm TL), sharpsnout seabream is equipped with free neuromasts and olfactory ciliated receptor cells. In the post-larval stage (5– 28.6 mm TL), mechano- and chemo-reception is implemented: the inner and outer taste buds differentiation, the nasal formation, the lateral line system canalization occur. The precocious differentiation of chemo-receptors makes post-larvae particularly sensitive to the organoleptic properties of administered preys. D. puntazzo, at the end of this phase, could be considered a juvenile (complete squamation is acquired), except for the mouth and pharyngeal teeth. During the subsequent phase (‘transitional’), in fact, eight chisel-type and two lateral series of molar-like teeth progressively substituted the conical ones on each jaw, and three different types of teeth on the upper and lower pharynx differentiated. So, the juvenile phase is reached in individuals longer than 58 mm TL
    • …
    corecore