Self-etch bonding agent beneath sealant: Bond strength for laser-irradiated enamel.

Objectives: This study evaluated the in vitro shear bond strength (SBS) of a resin-based pit-and-fissure sealant (Fluroshield [F], Dentsply/Caulk) associated with either an etch-and-rinse (Adper Single Bond 2 [SB], 3M/ESPE) or a two-step self-etch adhesive system (Adper SE Plus [SE], 3M/ESPE) on Er: YAG laser-irradiated enamel.

Materials And Methods: Seventeen sound third molar crowns were embedded in acrylic resin, and the mesial-distal enamel surfaces were flattened. The enamel sites were irradiated with a 2.

Synthesis, molecular docking and binding studies of selective serotonin transporter inhibitors.

With the aim of obtaining compounds possessing high SERT selectivity, in the present work we synthesized and studied the inhibition of serotonin (SERT), dopamine (DAT) and norepinephrine (NET) transporters by docking studies and experimental binding measurements of a series of 4-(aryl)piperidin-3-one O-4-benzyl oxime hydrochlorides (1-10) of both E and Z configuration. E configuration compounds showed high SERT binding affinities (K(i) = 10-98 nM) and high SERT selectivities over both NET and DAT. The molecular docking studies allowed a rationalization of the molecular basis of drug-SERT interactions both of the synthesized compounds and paroxetine and fluoxetine used as reference antidepressant drugs.

Dehydration enthalpy of alkali-cations-exchanged montmorillonite from thermogravimetric analysis.

Dehydration of a series of homoionic alkali-exchanged montmorillonites is studied at different treatment temperatures by means of thermogravimetric analysis. More specifically, we investigate the last stages of dehydration when the number of adsorbed water molecules corresponds, at maximum, to a monolayer. Weight losses are measured at several constant temperatures as a function of time.

DC conductivity, cationic exchange capacity, and specific surface area related to chemical composition of pore lining chlorites.

Low resistivity in argillaceous sandstone reservoirs may be attributed either to the effect of microporosity, or to specific effects due to intrinsic clays' conducting properties or to other conducting minerals. In order to distinguish these effects, cation exchange capacity, specific surface areas, and dc conductivity of various pore lining chlorite-bearing sandstones from different hydrocarbon reservoir measurements are investigated. Cation exchange capacity and specific surface area are measured on whole rocks as well as on size-separated fractions.

Hydration of a Na(+)-montmorillonite studied by thermally stimulated depolarization current.

Thermally stimulated depolarization current (TSDC) technique is a powerful tool for probing dipole re-orientational motions in condensed matter. In the case of cation-exchangeable aluminosilicates, it allows the assessment of the potential barrier related to the hopping mechanism of cations and, consequently, the measurement of its evolution when molecules, i.e.

Use of dielectric relaxation for measurements of surface energy variations during adsorption of water on mordenite.

This paper tries to assess simply and quantitatively the link between classical adsorption theories and dielectric spectroscopy, in order to demonstrate that dielectric spectroscopy can be used as a tool of determination of surface energy variations due to movements of charge carriers at the surface of solids. A simple theory is developed to analyze hops of cations at the surface of mordenite, which are detected by complex impedance spectroscopy during adsorption of water. An energy of extraction of the cation can be determined from measurements and its dependence on the quantity of water molecules adsorbed is shown and qualitatively and quantitatively explained, using relationships developed in order to interpret adsorption phenomena generally.

A simple model of entropy relaxation for explaining effective activation energy behavior below the glass transition temperature.

Strong changes in relaxation rates observed at the glass transition region are frequently explained in terms of a physical singularity of the molecular motions. We show that the unexpected trends and values for activation energy and preexponential factor of the relaxation time tau, obtained at the glass transition from the analysis of the thermally stimulated current signal, result from the use of the Arrhenius law for treating the experimental data obtained in nonstationary experimental conditions. We then demonstrate that a simple model of structural relaxation based on a time dependent configurational entropy and Adam-Gibbs relaxation time is sufficient to explain the experimental behavior, without invoking a kinetic singularity at the glass transition region.

Modulation of A1 adenosine receptor signaling by peroxynitrite.

Nitric oxide (NO) is a gaseous free radical involved in many pathophysiological processes. During oxidative stress, NO, its derivatives and adenosine are released. Considering adenosine neuroprotective role in the central nervous system (CNS) and toxicity of NO, we investigated the effect of a NO/peroxynitrite (ONOO(-)) donor, 3-morpholinosydnonimine (SIN-1), on A(1) adenosine receptor (A(1)AR) signaling pathway in rat cortical membranes.

Analysis of Thermally Stimulated Depolarization Currents (TSDC) Measured on Exchanged Clays.

This work shows that hydration of clays can be studied by means of a new interpretation of thermally stimulated depolarization currents technique. These measurements have been performed on four exchanged natural clays: Na-montmorillonite, Ca-montmorillonite, kaolinite, and illite. The results are analyzed using both the recently developed analysis of relaxation times distribution and the electronegativity equalization method.