Di Sante M.,Technical University of Marche
1st IMEKO TC4 International Workshop on Metrology for Geotechnics, MetroGeotechnics 2016 | Year: 2016
It is widely known that lime treatment of clayey soils enhances mechanical and hydraulic characteristics of soils. In soil-lime systems, this improvement is due to a sequence of chemical processes that results in reaction products detectable at meso- and micro-scale. Therefore the contribution of experimental techniques such as Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy and Mercury Intrusion Porosimetry turns out to be essential to analyze the results of geotechnical tests and to understand the behaviour of soil-lime mixtures. After a brief review of literature on the microstructure of lime stabilized soil, the paper presents the results of research studies carried out on clayey soils treated with lime by means of the previous cited techniques. © 2016, IMEKO-International Measurement Federation Secretariat. All rights reserved.
Tardani F.,University of Rome La Sapienza |
Sennato S.,National Research Council Italy |
Ortore M.G.,Technical University of Marche
Journal of Physical Chemistry C | Year: 2016
Processing carbon nanotubes (CNTs) into functional materials requires usage of multicomponent systems. Additives such as ionic surfactants, complex macromolecules (i.e., DNA, proteins), or colloidal nanoparticles are used for this purpose. Unfortunately, the high intrinsic nonideality of these systems makes predictions and simulations of their behavior challenging. That is why experimental investigations on the overall colloidal behavior are fundamental in developing CNT-based technologies. To that purpose, we have recently started a systematic characterization of (pseudo)ternary systems containing carbon nanotubes. In a previous study, we have characterized the re-entrant behavior of single-stranded DNA (ssDNA)/CNT in the presence of an oppositely charged surfactant. The ratio between ssDNA/nanotubes and surfactant defines the overall associative behavior. Irreversible aggregation is found close to the isoelectric point, while negatively or positively charged surfactant-ssDNA/nanotube complexes appear at ssDNA or surfactant (redispersion) excess, respectively. Here, we present a detailed investigation on the effects of surfactant chain length and ionic strength on the nanotubes' associative behavior by considering an approach involving different and complementary experimental techniques. The associative behavior is related to the micellization ability of surfactant. Interestingly, no redispersion is found for short chains with n < 14. The phase behavior is analyzed in comparison with the one of polyelectrolyte-surfactant-water system. © 2016 American Chemical Society.
Bibas M.,National Institute for Infectious Diseases |
Lorenzini P.,National Institute for Infectious Diseases |
Cozzi-Lepri A.,Institute of Epidemiology and Healthcare |
Calcagno A.,University of Turin |
And 6 more authors.
AIDS | Year: 2012
We investigated the association between polyclonal serum-free light chains and prognostic biomarkers routinely used in the setting of HIV infection. For this purpose serum samples of 182 HIV-infected patients from the Italian Cohort of Antiretroviral Naive Patients foundation cohort were analysed. We found that polyclonal serum free light chains above the upper normal limit are strongly correlated in HIV-infected patients with advancing age, shorter time of undetectable HIV viremia, higher viral load and with lower CD4 cell count at sample. Copyright © 2012 Lippincott Williams &Wilkins.
Grandi E.,University of California at Davis |
Pasqualini F.S.,Technical University of Marche |
Bers D.M.,University of California at Davis
Journal of Molecular and Cellular Cardiology | Year: 2010
We have developed a detailed mathematical model for Ca handling and ionic currents in the human ventricular myocyte. Our aims were to: (1) simulate basic excitation-contraction coupling phenomena; (2) use realistic repolarizing K current densities; (3) reach steady-state. The model relies on the framework of the rabbit myocyte model previously developed by our group, with subsarcolemmal and junctional compartments where ion channels sense higher [Ca] vs. bulk cytosol. Ion channels and transporters have been modeled on the basis of the most recent experimental data from human ventricular myocytes. Rapidly and slowly inactivating components of Ito have been formulated to differentiate between endocardial and epicardial myocytes. Transmural gradients of Ca handling proteins and Na pump were also simulated. The model has been validated against a wide set of experimental data including action potential duration (APD) adaptation and restitution, frequency-dependent increase in Ca transient peak and [Na]i. Interestingly, Na accumulation at fast heart rate is a major determinant of APD shortening, via outward shifts in Na pump and Na-Ca exchange currents. We investigated the effects of blocking K currents on APD and repolarization reserve: IKs block does not affect the former and slightly reduces the latter; IK1 blockade modestly increases APD and more strongly reduces repolarization reserve; IKr blockers significantly prolong APD, an effect exacerbated as pacing frequency is decreased, in good agreement with experimental results in human myocytes. We conclude that this model provides a useful framework to explore excitation-contraction coupling mechanisms and repolarization abnormalities at the single myocyte level. © 2009 Elsevier Inc. All rights reserved.
Capozucca R.,Technical University of Marche |
Maccioni V.,Technical University of Marche
Key Engineering Materials | Year: 2013
This paper deals with the effects of damage on Carbon Fibre Reinforced Polymer (CFRP) elements subjected to both defects and micro-cracking due to static tensile loading, by investigating CFRP elements under natural vibration tests. The correlation between response and frequency decrease due to damage for cross section reduction of CFRP cantilever beam elements is analysed. Successively, the response of CFRP lamina subjected to different tensile force values is investigated; experimental frequency values are compared with theoretical values and discussed. © (2013) Trans Tech Publications.