ABSTRACT
Recent experimental data on Bose-Einstein condensation of magnons in the spin-gap compound Yb_{2}Si_{2}O_{7} revealed an asymmetric Bose-Einstein condensation dome [G. Hester et al., Phys. Rev. Lett. 123, 027201 (2019)PRLTAO0031-900710.1103/PhysRevLett.123.027201]. We examine modifications to the Heisenberg model on a breathing honeycomb lattice, showing that this physics can be explained by competing anisotropic perturbations. We employ a gamut of analytical and numerical techniques to show that the anisotropy yields a field driven phase transition from a state with broken Ising symmetry to a phase that breaks no symmetries and crosses over to the polarized limit.
ABSTRACT
Historical methods of functional development in density functional theory have often been guided by analytic conditions that constrain the exact functional one is trying to approximate. Recently, machine-learned functionals have been created by interpolating the results from a small number of exactly solved systems to unsolved systems that are similar in nature. For a simple one-dimensional system, using an exact condition, we find improvements in the learning curves of a machine learning approximation to the non-interacting kinetic energy functional. We also find that the significance of the improvement depends on the nature of the interpolation manifold of the machine-learned functional.
ABSTRACT
CASE: Protein S deficiency, a hypercoagulable thrombophilia, often results in venous thromboembolism. Nontraumatic compartment syndrome in a patient with protein S deficiency has not been well publicized. Herein, we present a rare case of nontraumatic compartment syndrome of the hand and the thigh in a 48-year-old woman with a known history of protein S deficiency; emergency fasciotomies were needed. CONCLUSION: Based on our patient and a review of the current literature, we advocate for a heightened awareness of compartment syndrome in patients with protein S deficiency.
