Multiple Faces of Cervical Lesions in Children.

Pediatric sialolithiasis is a rare condition causing tumefaction, induration, redness, and pain of the affected gland. When the submandibular gland is involved, the lesion can be mistaken for an adenopathy. As there are few studies to elucidate this condition in children, we present a rare case of a 16-year-old female with suggestive symptoms, in which initial clinical examination and two ultrasound examinations mistook the lesion for an adenopathy.

Multiparticle Quantum Walks and Fisher Information in One-Dimensional Lattices.

Recent experiments on quantum walks (QWs) demonstrated a full control over the statistics-dependent walks of single particles and two particles in one-dimensional lattices. However, little is known about the general characterization of QWs at the many-body level. Here, we rigorously study QWs, Bloch oscillations, and the quantum Fisher information for three indistinguishable bosons and fermions in one-dimensional lattices using a time-evolving block decimation algorithm and many-body perturbation theory.

Quench dynamics of the anisotropic Heisenberg model.

We develop an analytical approach for the study of the quench dynamics of the anisotropic Heisenberg model (XXZ model) on the infinite line. We present the exact time-dependent wave functions after a quench in an integral form for any initial state and for any anisotropy Δ by means of a generalized Yudson contour representation. We calculate the evolution of several observables from two particular initial states: starting from a local Néel state we calculate the time evolution of the antiferromagnetic order parameter-staggered magnetization; starting from a state with consecutive flipped spins (1) we calculate the evolution of the local magnetization and express it in terms of the propagation of magnons and bound state excitations, and (2) we predict the evolution of the induced spin currents.

Quench dynamics of the interacting Bose gas in one dimension.

We obtain an exact expression for the time evolution of the interacting Bose gas following a quench from a generic initial state using the Yudson representation for integrable systems. We study the time evolution of the density and noise correlation for a small number of bosons and their asymptotic behavior for any number. We show that for any value of the coupling, as long as it is repulsive, the system asymptotes towards a strongly repulsive gas, while for any value of an attractive coupling the long time behavior is dominated by the maximal bound state.

[Prevention of postoperative adhesions].

Postoperative adhesions represent a common consequence in patients who underwent abdominal or pelvic surgery. Such adhesions can be asymptomatic, but they can cause complications such as chronic abdomino-pelvic pain, secondary infertility, an increase in bowel obstruction risk and more complexity for future surgery, including longer surgery times and an increase in morbidity. Normally, adhesions appear after offences against the peritoneum, causing flogosys, and develop both in new sites, previously not involved, and in sites already interested in adhesiolysis.

Nonequilibrium quantum impurities: from entropy production to information theory.

Nonequilibrium steady-state currents, unlike their equilibrium counterparts, continuously dissipate energy into their physical surroundings leading to entropy production and time-reversal symmetry breaking. This Letter discusses these issues in the context of quantum impurity models. We use simple thermodynamic arguments to define the rate of entropy production sigma and show that sigma has a simple information-theoretic interpretation in terms of nonequilibrium distribution functions.

Nonequilibrium transport in quantum impurity models: the Bethe ansatz for open systems.

We develop an exact nonperturbative framework to compute steady-state properties of quantum impurities subject to a finite bias. We show that the steady-state physics of these systems is captured by nonequilibrium scattering eigenstates which satisfy an appropriate Lippman-Schwinger equation. Introducing a generalization of the equilibrium Bethe ansatz--the nonequilibrium Bethe ansatz--we explicitly construct the scattering eigenstates for the interacting resonance level model and derive exact, nonperturbative results for the steady-state properties of the system.

Theory of inelastic scattering from magnetic impurities.

We use the numerical renormalization group method to calculate the single-particle matrix elements T of the many-body T matrix of the conduction electrons scattered by a magnetic impurity at T=0 temperature. Since T determines both the total and the elastic, spin-diagonal scattering cross sections, we are able to compute the full energy, spin, and magnetic field dependence of the inelastic scattering cross section sigma(inel)(omega). We find an almost linear frequency dependence of sigma(inel)(omega) below the Kondo temperature T(K), which crosses over to a omega(2) behavior only at extremely low energies.

Solution of the two-channel Anderson impurity model: implications for the heavy fermion UBe13.

We solve the two-channel Anderson impurity model using the Bethe-ansatz. We determine the ground state and derive the thermodynamics, obtaining the impurity entropy and specific heat over the full range of temperature. We show that the low-temperature physics is given by a line of fixed points describing a two-channel non-Fermi-liquid behavior in the integral valence regime associated with moment formation as well as in the mixed valence regime where no moment forms.

Conductivity of a clean one-dimensional wire.

We study the low-temperature low-frequency conductivity sigma of an interacting one-dimensional electron system in the presence of a periodic potential. The conductivity is strongly influenced by conservation laws, which, we argue, need to be violated by at least two noncommuting umklapp processes to render sigma finite. The resulting dynamics of the slow modes is studied within a memory matrix approach, and we find an exponential increase as the temperature is lowered, sigma approximately (Deltan)(2)e(T0/(NT)) close to commensurate filling M/N, Deltan = n-M/N<<1, and sigma approximately e((T(')(0)/T)(2/3)) elsewhere.