Simultaneous thermal and contraction/expansion analyses of cast iron solidification process

Journal of Thermal Analysis and Calorimetry - Simultaneous thermal and contraction/expansion analysis of hypoeutectic grey (lamellar graphite) and ductile (nodular graphite) cast irons...     

Evidence for core-shell magnetic behavior in antiferromagnetic Co3O4 nanowires

Employing magnetometry measurements, we have studied Co3O4 nanowires focusing on the core-shell behavior. We find two magnetic contributions, i.e., a regular antiferromagnetic and an additional irreversible one. The first contribution can be attributed to the antiferromagnetically ordered wire cores. The nature of the second one can be identified using thermoremanent and isothermoremanent magnetizaton curves as magnetic fingerprints of the irreversible magnetization. We conclude that the nanowire shell behaves like a two-dimensional diluted antiferromagnet in a field.     

Reproducibility of the quantitative assessment of cartilage morphology and trabecular bone structure with magnetic resonance imaging at 7 T

To assess the reproducibility of quantitative measurements of cartilage morphology and trabecular bone structure of the knee at 7 T, high-resolution sagittal spoiled gradient-echo images and high-resolution axial fully refocused steady-state free-precession (SSFP) images from six healthy volunteers were acquired with a 7-T scanner. The subjects were repositioned between repeated scans to test the reproducibility of the measurements. The reproducibility of each measurement was evaluated using the coefficient(s) of variation (CV). The computed CV were 1.13% and 1.55% for cartilage thickness and cartilage volume, respectively, and were 2.86%, 1.07%, 2.27% and 3.30% for apparent bone volume over total volume fraction (app.BV/TV), apparent trabecular number (app.Tb.N), apparent trabecular separation (app.Tb.Sp) and apparent trabecular thickness (app.Tb.Th), respectively. The results demonstrate that quantitative assessment of cartilage morphology and trabecular bone structure is reproducible at 7 T and motivates future musculoskeletal applications seeking the high-field strength's superior signal-to-noise ratio.     

Density of impurity states of shallow donors in a quantum well under intense laser field

The density of donor impurity states in a square GaAs–AlGaAs quantum well under an intense laser field is calculated taking into account the laser dressing effects on both the Coulomb potential and the confining potential. Using the effective-mass approximation within a variational scheme, the donor binding energy is obtained as a function of the laser dressing parameter, and the impurity position. Our results point out that a proper consideration of the density of impurity states may be of relevance in the interpretation of the optical phenomena related to shallow impurities in quantum wells, where the effects of an intense laser field compete with the quantum confinement.     

Aqueous Sulfate Separation by Crystallization of Sulfate–Water Clusters

An effective approach to sulfate separation from aqueous solutions is based on the crystallization of extended [SO₄(H₂O)₅²⁻]_n sulfate–water clusters with a bis(guanidinium) ligand. The ligand was generated in situ by hydrazone condensation in water, thereby bypassing the need for elaborate syntheses, tedious purifications, and organic solvents. Crystallization of sulfate–water clusters represents an alternative approach to the now established sulfate separation strategies that involve encapsulation of the “naked” anion.     

Active control of liquid film flows: beyond reduced-order models

Nonlinear Dynamics - The ability to robustly and efficiently control the dynamics of nonlinear systems lies at the heart of many current technological challenges, ranging from drug delivery systems...     

The Effect of Calcium-Silicate Cements on Reparative Dentinogenesis Following Direct Pulp Capping on Animal Models

Dental pulp vitality is a desideratum for preserving the health and functionality of the tooth. In certain clinical situations that lead to pulp exposure, bioactive agents are used in direct pulp-capping procedures to stimulate the dentin-pulp complex and activate reparative dentinogenesis. Hydraulic calcium-silicate cements, derived from Portland cement, can induce the formation of a new dentin bridge at the interface between the biomaterial and the dental pulp. Odontoblasts are molecularly activated, and, if necessary, undifferentiated stem cells in the dental pulp can differentiate into odontoblasts. An extensive review of literature was conducted on MedLine/PubMed database to evaluate the histological outcomes of direct pulp capping with hydraulic calcium-silicate cements performed on animal models. Overall, irrespective of their physico-chemical properties and the molecular mechanisms involved in pulp healing, the effects of cements on tertiary dentin formation and pulp vitality preservation were positive. Histological examinations showed different degrees of dental pulp inflammatory response and complete/incomplete dentin bridge formation during the pulp healing process at different follow-up periods. Calcium silicate materials have the ability to induce reparative dentinogenesis when applied over exposed pulps, with different behaviors, as related to the animal model used, pulpal inflammatory responses, and quality of dentin bridges.