Modern algorithm for diagnosis and treatment of the functional dyspepsia syndrome

The article tells about current diagnostic criteria for the syndrome of functional dyspepsia; major clinical variants of the disease and the process; modern algorithm revealing the main stages of diagnosis and treatment of patients with functional dyspepsia in clinical practice. The role of eradication of Helicobacter pylori infection in multimodal treatment of functional dyspepsia is highlighted

Quasi-two-dimensional thermoelectricity in SnSe

Stannous selenide is a layered semiconductor that is a polar analog of black phosphorus and of great interest as a thermoelectric material. Unusually, hole doped SnSe supports a large Seebeck coefficient at high conductivity, which has not been explained to date. Angle-resolved photoemission spectroscopy, optical reflection spectroscopy, and magnetotransport measurements reveal a multiple-valley valence-band structure and a quasi-two-dimensional dispersion, realizing a Hicks-Dresselhaus thermoelectric contributing to the high Seebeck coefficient at high carrier density. We further demonstrate that the hole accumulation layer in exfoliated SnSe transistors exhibits a field effect mobility of up to 250 cm(2)/V s at T = 1.3K. SnSe is thus found to be a high-quality quasi-two-dimensional semiconductor ideal for thermoelectric applications

Anomalous behavior of the electronic structure of Bi1 xInx 2Se3 across the quantum phase transition from topological to trivial insulator

Using spin- and angle-resolved photoemission spectroscopy and relativistic many-body calculations, we investigate the evolution of the electronic structure of (Bi1−xInx)2Se3 bulk single crystals around the critical point of the trivial to topological insulator quantum-phase transition. By increasing x, we observe how a surface gap opens at the Dirac point of the initially gapless topological surface state of Bi2Se3, leading to the existence of massive fermions. The surface gap monotonically increases for a wide range of x values across the topological and trivial sides of the quantum-phase transition. By means of photon-energy-dependent measurements, we demonstrate that the gapped surface state survives the inversion of the bulk bands which occurs at a critical point near x=0.055. The surface state exhibits a nonzero in-plane spin polarization which decays exponentially with increasing x, and which persists in both the topological and trivial insulator phases. Our calculations reveal qualitative agreement with the experimental results all across the quantum-phase transition upon the systematic variation of the spin-orbit coupling strength. A non-time-reversal symmetry-breaking mechanism of bulk-mediated scattering processes that increase with decreasing spin-orbit coupling strength is proposed as explanation