Quantitative Edge Analysis Can Differentiate Pancreatic Carcinoma from Normal Pancreatic Parenchyma.

This study aimed to introduce specific image feature analysis, focusing on pancreatic margins, and to provide a quantitative measure of edge irregularity, evidencing correlations with the presence/absence of pancreatic adenocarcinoma. We selected 50 patients (36 men, 14 women; mean age 63.7 years) who underwent Multi-detector computed tomography (MDCT) for the staging of pancreatic adenocarcinoma of the tail of the pancreas.

Screening and Antiscreening Effects in Endohedral Nanotubes.

Recently we investigated from first-principles screening properties in systems where small molecules, characterized by a finite electronic dipole moment, are encapsulated in different nanocages. The most relevant result was the observation of an antiscreening effect in alkali-halide nanocages characterized by ionic bonds: in fact, due to the relative displacement of positive and negative ions, induced by the dipole moment of the encapsulated molecule, these cages act as dipole-field amplifiers, different from what is observed in carbon fullerene nanocages, which exhibit instead a pronounced screening effect. Here we extend the study to another class of nanostructures: the nanotubes.

Superfluidity Meets the Solid State: Frictionless Mass Transport through a (5,5) Carbon Nanotube.

Superfluidity is a well-characterized quantum phenomenon which entails frictionless motion of mesoscopic particles through a superfluid, such as ^{4}He or dilute atomic gases at very low temperatures. As shown by Landau, the incompatibility between energy and momentum conservation, which ultimately stems from the spectrum of the elementary excitations of the superfluid, forbids quantum scattering between the superfluid and the moving mesoscopic particle, below a critical speed threshold. Here, we predict that frictionless motion can also occur in the absence of a standard superfluid, i.

Quantum-mechanical water-flow enhancement through a sub-nanometer carbon nanotube.

Experimental observations unambiguously reveal quasi-frictionless water flow through nanometer-scale carbon nanotubes (CNTs). Classical fluid mechanics is deemed unfit to describe this enhanced flow, and recent investigations indicated that quantum mechanics is required to interpret the extremely weak water-CNT friction. In fact, by quantum scattering, water can only release discrete energy upon excitation of electronic and phononic modes in the CNT.

MBD + C: How to Incorporate Metallic Character into Atom-Based Dispersion Energy Schemes.

The dispersion component of the van der Waals interaction in low-dimensional metals is known to exhibit anomalous "Type-C non-additivity" [ 1157]. This causes dispersion energy behavior at asymptotically large separations that is missed by popular atom-based schemes for dispersion energy calculations. For example, the dispersion interaction energy between parallel metallic nanotubes at separation falls off asymptotically as approximately , whereas current atom-based schemes predict asymptotically.