Bistable defect structures in blue phase devices
Blue phases are liquid crystals made up by networks of defects, or disclination lines. While existing phase diagrams show a striking variety of competing metastable topologies for these networks, very little is known as to how to kinetically reach a target structure, or how to switch from one to the other, which is of paramount importance for devices. We theoretically identify two confined blue phase I systems in which by applying an appropriate series of electric field it is possible to select one of two bistable defect patterns.
Convergence in probability of the Mallows and GCV wavelet and Fourier regularization methods
Wavelet and Fourier regularization methods are effective for the nonparametric regression problem. We prove that the loss function evaluated for the regularization parameter chosen through GCV or Mallows criteria is asymptotically equivalent in probability to its minimum over the regularization parameter. © 2001 Elsevier Science B.V.
Gravitomagnetic Helicity
Mass currents in astrophysics generate gravitomagnetic fields of enormous complexity. Gravitomagnetic
helicity, in direct analogy with magnetic helicity, is a measure of entwining of the gravitomagnetic field
lines. We discuss gravitomagnetic helicity within the gravitoelectromagnetic (GEM) framework of
linearized general relativity. Furthermore, we employ the spacetime curvature approach to GEM in order
to determine the gravitomagnetic helicity for static observers in Kerr spacetime.
Cardiac function in adolescents and young adults with 22q11.2 deletion syndrome without congenital heart disease
Background
Diagnosis and treatment of 22q11.2 deletion syndrome (22q11.2DS) have led to improved life expectancy and achievement of adulthood. Limited data on long-term outcomes reported an increased risk of premature death for cardiovascular causes, even without congenital heart disease (CHD).
The Knapsack Problem with forfeit sets
This work introduces a novel extension of the 0/1 Knapsack Problem in which we consider the existence of so-called forfeit sets. A forfeit set is a subset of items of arbitrary cardinality, such that including a number of its elements that exceeds a predefined allowance threshold implies some penalty costs to be paid in the objective function value. A global upper bound on these allowance violations is also considered.
Continuum theory of phase separation kinetics for active brownian particles
Active Brownian particles (ABPs), when subject to purely repulsive interactions, are known to undergo activity-induced phase separation broadly resembling an equilibrium (attraction-induced) gas-liquid coexistence. Here we present an accurate continuum theory for the dynamics of phase-separating ABPs, derived by direct coarse graining, capturing leading-order density gradient terms alongside an effective bulk free energy. Such gradient terms do not obey detailed balance; yet we find coarsening dynamics closely resembling that of equilibrium phase separation.