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161.
163.
Silvana Fiorito Marc Monthioux Pasquale Pierimarchi Enrico D’Emilia Antonella Lisi Robert Almairac Annalucia Serafino 《Carbon》2009,47(12):2789-817
Carbon multi-walled nanotubes (MWCNTs) may have several dangerous effects on different cell systems, but the mechanisms responsible for their cytotoxicity are not well known yet. At present, very little is known about the electrical interactions between nanomaterials and cells. We aimed to verify whether MWCNT electrical properties could affect the so called “charge-sensitive” cell parameters, interacting with cellular electrical activity. Human macrophages were challenged with two fully characterised MWCNT samples, one tested as-prepared (MWCNT), the other one purified (by annealing at 2400 °C) and better electro-conductive (a-MWCNT). Our findings show that a-MWCNTs are less cytotoxic but possess a higher inflammatory potential, as compared to MWCNTs. Moreover, only annealed and better conductive MWCNTs affect significantly the mitochondrial membrane polarity, the intracellular pH and the reorganisation of cytoskeleton actin filaments, cell functions strictly dependent on electro-chemical mechanisms. Based on our results, there is evidence for electro-chemical interactions taking place between cell membranes and electro-conductive MWCNTs. Such a specific behaviour could have wide-range applications in the biomedical field, not only concerning those cellular systems (neuronal and bone cells) sensitive to electrical stimuli, but also other cell systems. 相似文献
164.
Mazzoni Giuliana A. L.; Lombardo Pasquale; Malvagia Stefano; Loftus Elizabeth F. 《Canadian Metallurgical Quarterly》1999,30(1):45
Dream interpretation is a common practice in psychotherapy. In the research presented in this article, each participant saw a clinician who interpreted a recent dream report to be a sign that the participant had had a mildly traumatic experience before age 3 years, such as being lost for an extended time or feeling abandoned by his or her parents. This dream intervention caused a majority of participants to become more confident that they had had such an experience, even though they had previously denied it. These findings have implications for the use of dream material in clinical settings. In particular, the findings point to the possibility that dream interpretation may have unexpected side effects if it leads to beliefs about the past that may, in fact, be false. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
165.
A simplified model is proposed to evaluate the BWR plant depressurization transient subsequent to the activation of a single safety relief valve. The model is validated with a series of RELAP5 Mod 3 calculations yielding reasonable comparisons. The depressurization behavior of the 26 US BWR plants is analyzed with the model and the relevant parameters controlling the process are identified. Of these, four are plant-specific and their effect on the final outcome of the depressurization transient is quantified. The minimum vessel inventory at the activation of the low pressure emergency core coolant injection is selected as the figure of merit. Core power is the only parameter that significantly affects the outcome of the transient. The role of the low pressure injection and of the discharge port cross-sectional area is discussed in detail. The effect of operator actions on the control rod drive (CRD) injection flow is also discussed. 相似文献
166.
Alberto Ballestra Eugenio Brusa Giorgio De Pasquale Mircea Gh. Munteanu Aurelio Somà 《Analog Integrated Circuits and Signal Processing》2010,63(3):477-488
Out-of-plane bending tests are here used to experimentally validate some numerical models of microbeams actuated by the electric
field. Out-of-plane bending microcantilevers and clamped–clamped microbeams often suffer the presence of residual strain and
stress, respectively, which affect their static and dynamic behaviour and pull-in voltage. In case of microcantilever an accurate
modelling has to include the effect of an initial curvature due to microfabrication process, while in double clamped microbeams
constraints may impose a pre-loading caused by a tensile stress. So-called geometrical nonlinearity sometimes occurs, when
microcantilever exhibits large displacement, or because of the mechanical coupling between axial and flexural behaviours in
double clamped microbeams. Modelling this kind of nonlinearity is an additional goal of this study. Experiments demonstrated
a good agreement with results of FEM approaches proposed. In the case of microbridges numerical models are used to identify
the residual stress. A reverse analysis is implemented, the axial pre-stress is calculated by means of the measured pull-in
voltage. 相似文献
167.
Stefano Barone Paolo D'Ambrosio Pasquale Erto 《Quality and Reliability Engineering International》2007,23(5):565-575
The current generation of vehicle models are increasingly being equipped with on‐board diagnostic (OBD) systems aimed at assessing the ‘state of health’ of important anti‐pollution subsystems and components. In order to promptly diagnose and fix quality and reliability problems that may potentially affect such complex diagnostic systems, even during advanced development prior to mass production, some vehicle prototypes undergo a testing phase under realistic conditions of use (a mileage accumulation campaign). The aim of this work is to set up a statistical tool for improving the reliability of the OBD system by monitoring its operation during the mileage accumulation campaign of a new vehicle model. A dedicated software program was developed by the authors to filter the large experimental database recorded during the mileage accumulation campaign and to extract the time series of the diagnostic indices to be analysed. A model‐based monitoring approach, using continuous time autoregressive (CAR) models for the time‐series structure and traditional control charts for the estimated residuals, is adopted. A Kalman recursion procedure for the estimation of the unknown CAR model parameters is described. An application of the proposed approach is presented for a diagnostic index related to the state of health of the oxygen sensor. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
168.
Rosalba Lanciotti Francesca PatrignaniLuciana Iucci Pasquale SaracinoM. Elisabetta Guerzoni 《Food chemistry》2007,102(2):542-550
Different species of Lactobacillus involved in dairy product fermentation and ripening were considered in order to study the effect of high pressure homogenization (HPH) on: (i) fermentation kinetics of HPH treated cells inoculated in milk; (ii) metabolic profiles; (iii) release of intracellular proteolytic enzymes; and (iv) enhance of the activity of extracellular or cellular wall located proteolytic enzymes. The HPH treatments applied were 50, 100, 150 MPa, 2 cycles at 50 and at 100 MPa. The viability loss did not exceed 1.3 log cfu/ml after the higher treatments applied. The electrophoretic profiles of α- or β-casein incubated with the different cell free filtrates shown that HPH positively affected the proteolytic activity of some strains. Moreover, HPH affected the acidification rates of the milk inoculated with the processed cells and the primary metabolism of some strains. Regarding volatile compounds, ethanol, acetoin and 2-methyl butyric acid were subjected to the major changes when the inoculum had been processed. 相似文献
169.
Molecular approaches by means of a combined use of mass spectrometric techniques can be important in order to open new possibilities in the differentiation and defense of typical products; in this study, a possible approach to the analysis of varietal volatile compounds and some precursors of a non-aromatic grape variety (Falanghina cv., Vitis vinifera L.) was traced through a combined use of techniques based on mass spectrometry (GC/MS, LC/ESI-MS, MALDI-TOF-MS). Dominant terpene compounds (limonene, cis-furanlinalool oxide, geraniol, 4-carene, myrcene, linalool, -terpineol), terpene-derivatives (bornyl acetate, menthol), terpene glycosides (glucosides, arabinosylglucosides and rhamnosylglucosides of linalool and geraniol), and norisoprenoids (β-damascenone) were identified in grapes and monovarietal wines, overcoming the analytical difficulties deriving from the low concentration of these compounds strictly related to the variety. The potential release of varietal volatile compounds from the grapes was also explored by enzyme hydrolysis. 相似文献
170.
We present a longitudinal multimode pumping scheme which allows Yb-sensitized Er-doped silica waveguide amplifiers to be effectively pumped by high-power and low-cost broad-area lasers. The proposed configuration is based on evanescent pump light coupling from a multimode low-loss waveguide to a Er-Yb codoped active core. Theoretical predictions, based on propagation and population-rate equations for the coupled Er-Yb system, show that longitudinal multimode pumping by high-power broad-area lasers at around 980 nm can provide up to 4-dB gain per centimeter, suggesting possible integration of low-cost amplifiers with important applications in wavelength-division-multiplexing metro and access optical networks. 相似文献