Clocking Koufax

In lieu of an abstract, below is the essay\u27s first paragraph. Walking out of the tunnels of Baltimore’s Memorial Stadium, even after the roaring crowds had departed in compressed streams of red taillights, was the best part of the evening, John Angelina had decided early in the baseball season. Especially now that the Orioles were headed for a pennant and possibly the World Series, the line of groupies would wait for the pitchers. Not that the other players or positions were any less attractive, it was just something about the pitchers. Particularly that battery of pitchers that year that would in fact find heroes in all unlikely places and circumstances; that year that would deliver a resounding win at the World Series against the legendary Los Angeles Dodgers and the brilliant Sandy Koufax

Cohesive properties of noble metals by van der Waals-corrected Density Functional Theory

The cohesive energy, equilibrium lattice constant, and bulk modulus of noble metals are computed by different van der Waals-corrected Density Functional Theory methods, including vdW-DF, vdW-DF2, vdW-DF-cx, rVV10 and PBE-D. Two specifically-designed methods are also developed in order to effectively include dynamical screening effects: the DFT/vdW-WF2p method, based on the generation of Maximally Localized Wannier Functions, and the RPAp scheme (in two variants), based on a single-oscillator model of the localized electron response. Comparison with results obtained without explicit inclusion of van der Waals effects, such as with the LDA, PBE, PBEsol, or the hybrid PBE0 functional, elucidates the importance of a suitable description of screened van der Waals interactions even in the case of strong metal bonding. Many-body effects are also quantitatively evaluated within the RPAp approach.Comment: 3 figure

Hidden by graphene -- towards effective screening of interface van der Waals interactions via monolayer coating

Recent atomic force microscopy (AFM) experiments~[ACS Nano {\bf 2014}, 8, 12410-12417] conducted on graphene-coated SiO$_2$ demonstrated that monolayer graphene (G) can effectively screen dispersion van der Waals (vdW) interactions deriving from the underlying substrate: despite the single-atom thickness of G, the AFM tip was almost insensitive to SiO$_2$, and the tip-substrate attraction was essentially determined only by G. This G vdW {\it opacity} has far reaching implications, encompassing stabilization of multilayer heterostructures, micromechanical phenomena or even heterogeneous catalysis. Yet, detailed experimental control and high-end applications of this phenomenon await sound physical understanding of the underlying physical mechanism. By quantum many-body analysis and ab-initio Density Functional Theory, here we address this challenge providing theoretical rationalization of the observed G vdW {\it opacity} for weakly interacting substrates. The non-local density response and ultra slow decay of the G vdW interaction ensure compensation between standard attractive terms and many-body repulsive contributions, enabling vdW {\it opacity} over a broad range of adsorption distances. vdW {\it opacity} appears most efficient in the low frequency limit and extends beyond London dispersion including electrostatic Debye forces. By virtue of combined theoretical/experimental validation, G hence emerges as a promising ultrathin {\it shield} for modulation and switching of vdW interactions at interfaces and complex nanoscale devices

Van der Waals Interactions in DFT using Wannier Functions without empirical parameters

A new implementation is proposed for including van der Waals (vdW) interactions in Density Functional Theory (DFT) using the Maximally-Localized Wannier functions (MLWFs), which is free from empirical parameters. With respect to the previous DFT/vdW-WF2 method, in the present DFT/vdW-WF2-x approach, the empirical, short-range, damping function is replaced by an estimate of the Pauli exchange repulsion, also obtained by the MLWFs properties. Applications to systems contained in the popular S22 molecular database and to the case of an Ar atom interacting with graphite, and comparison with reference data, indicate that the new method, besides being more physically founded, also leads to a systematic improvement in the description of vdW-bonded systems.Comment: 3 figures. arXiv admin note: text overlap with arXiv:1111.6737, arXiv:1305.7035, arXiv:1603.0866

Alamogordo

In lieu of an abstract, below is the essay\u27s first paragraph. The road into Clovis had been tortuous but tinted with the colors of the New Mexico desert subtly touched by the incipient autumn. Driving a military Jeep with a comrade from their former B-17 squadrons in Europe, Joseph Angelina thought how different it would be to fly in this clear, dry air, so remarkably pure after his recent years of trying to locate enemy targets in cloudy and moody Europe

Multiplicity results for some nonlinear Schroedinger equations with potentials

We prove some multiplicity results for a nonlinear equation of Schroedinger type with potential function

Quantum Monte Carlo study of circular quantum dots in presence of Rashba interaction

We present the numerical Quantum Monte Carlo results for the ground state energy of circular quantum dots in which Rashba spin-orbit iteraction is present. Diffusion Monte Carlo with spin propagation is applied in order to treat the spin-orbit interaction correctly, following previous work done in the fieldof the two-dimensional electron gas. Together with ground state energies, also numerical results for density and spin-density profiles are given

Acute Diverticulitis of the Left Colon: Value of the Initial CT and Timing of Elective Colectomy

Computed Tomography is undeniably the most useful tool to confirm the suspected diagnosis of acute left-colonic diverticulitis and to objectively grade its severity into moderate diverticulitis (no signs of colonic perforation) and severe diverticulitis (signs of colonic perforation). Indeed, the severity of acute diverticulitis is statistically predictive of the risk both to need surgical treatment of the first episode of acute diverticulitis, and to follow a complicated evolution after successful conservative treatment of the acute phase. Consequently, CT brings a major contribution to define the place of surgery during the acute phase of diverticulitis, and, later on, inside the long-term evolution of the disease after initial successful conservative treatmen