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Leptospirosis presents a significant health challenge in the Transcarpathian region of Ukraine, with higher incidence rates and mortality compared to national averages. We conducted a retrospective cohort study to investigate the effects of antibiotic and steroid treatments on outcomes in leptospirosis patients. Our analysis of clinical and laboratory data from a single center revealed that dexamethasone showed significant effects on various clinical variables, as did investigated antibiotics. Notable differences in clinical and laboratory outcomes were observed, particularly in direct bilirubin levels, which were significantly higher in non-survivors. ROC analysis demonstrated high sensitivity and specificity of direct bilirubin as a predictor of mortality. These findings highlight the importance of targeted treatment strategies and the potential of specific laboratory markers in improving leptospirosis management. [ABSTRACT FROM AUTHOR]

Using DFT-based molecular dynamics simulation of Cu+ cations flipping and In3+ cations displacive dynamics, we clarify the dipole ordering of CuInP2S6 ferrielectrics through the second order Jahn-Teller effect which determines the double-well potential for copper cations as well as three-well potential for indium cations inside the structural layers. The temperature dependence of the spatial distribution of Cu+ and In3+ cations is also described within the quantum anharmonic oscillator model. In3+ cations play a decisive role in the character of the polar ordering: at ambient or for positive pressures, the first order transition occurs; with the rise of negative compression, the ferrielectric transition evolves to the second order. The peculiarities of spontaneous polarization switching are related to the contributions of copper and indium cationic sublattices. [ABSTRACT FROM AUTHOR]

Using DFT-based molecular dynamics simulation of Cu+ cations flipping and In3+ cations displacive dynamics, we clarify the dipole ordering of CuInP2S6 ferrielectrics through the second order Jahn-Teller effect which determines the double-well potential for copper cations as well as three-well potential for indium cations inside the structural layers. The temperature dependence of the spatial distribution of Cu+ and In3+ cations is also described within the quantum anharmonic oscillator model. In3+ cations play a decisive role in the character of the polar ordering: at ambient or for positive pressures, the first order transition occurs; with the rise of negative compression, the ferrielectric transition evolves to the second order. The peculiarities of spontaneous polarization switching are related to the contributions of copper and indium cationic sublattices. [ABSTRACT FROM AUTHOR]

For the first time, we demonstrated successful post-synthesis incorporation of metal dopants at elevated temperature into a host structure of Sn2P2S6, known as the grandfather of dichalcogenide ferroelectrics with a formula M2P2X6 (M = metal and X = chalcogen). With the example of Cu, we show that the integration of dopant atoms into the bulk of an already grown crystal could be easily tuned up to 0.5 at% affecting the structural, optical, vibrational, electrical, and ferroelectric properties. Thermally diffused copper atoms in Sn2P2S6 bulk are in the metallic state, inducing a multiaxial expansion of the Sn2P2S6 unit cell for 2–3.4%. The energy reduction between indirect and direct optical transitions was observed, combined by small hardening for acoustic and soft optical vibrational modes originating in the partial substitution of Sn by Cu in the Sn2P2S6 crystal lattice. Similar to hydrostatic pressure, the structurally bonded copper initiates a small downward shift in the critical temperature Tc. The presence of copper has a substantial impact on the shape smearing of the ferroelectric domains as well as on the behaviour of the dielectric permittivity. The real part of the dielectric constant ε′ reaches its maximal value at intermediate concentrations of Cu 0% < x < 0.5%, showing an ∼20% increase with respect to the parent structure. The incorporated metal atoms provoke a monotonous expansion of the ferroelectric P–E loops along the increased dopant content direction. An increase in the electrical conductivity at higher Cu concentration reveals a trend for inducing a metal-like behaviour. [ABSTRACT FROM AUTHOR]

Elastic properties of (PbSn)PS solid solutions were studied using Brillouin scattering technique. Different scattering geometries were used for sound velocities determination that make it possible to find all components of the stiffness tensor. The concentration dependencies of volume compressibility, the Grüneisen parameter and Debye temperature were investigated. The results obtained were used to analyze chemical bonding with substitution of tin by lead at room temperature in the crystals under consideration. [ABSTRACT FROM AUTHOR]

The temperature and frequency dependencies of sound attenuation for the proper uniaxial ferroelectric SnPS, which has a strong nonlinear interaction of the polar soft optic and fully symmetrical optic modes that is related to the triple well potential, were studied by Brillouin spectroscopy. It was found that the sound velocity anomaly is described in the Landau-Khalatnikov approximation with one relaxation time. For explanation of the observed temperature and frequency dependencies of the sound attenuation in the ferroelectrric phase, the accounting of several relaxation times is needed and, for quantitative calculations, the mode Gruneisen coefficients are more appropriate as interacting parameters than are the electrostrictive coefficients. Relaxational sound attenuation by domain walls also appears in the ferroelectric phase of SnPS crystals. [ABSTRACT FROM AUTHOR]

Using DFT-based molecular dynamics simulation of Cu+ cations flipping and In3+ cations displacive dynamics, we clarify the dipole ordering of CuInP2S6 ferrielectrics through the second order Jahn-Teller effect which determines the double-well potential for copper cations as well as three-well potential for indium cations inside the structural layers. The temperature dependence of the spatial distribution of Cu+ and In3+ cations is also described within the quantum anharmonic oscillator model. In3+ cations play a decisive role in the character of the polar ordering: at ambient or for positive pressures, the first order transition occurs; with the rise of negative compression, the ferrielectric transition evolves to the second order. The peculiarities of spontaneous polarization switching are related to the contributions of copper and indium cationic sublattices. [ABSTRACT FROM AUTHOR]

Using DFT-based molecular dynamics simulation of Cu+ cations flipping and In3+ cations displacive dynamics, we clarify the dipole ordering of CuInP2S6 ferrielectrics through the second order Jahn-Teller effect which determines the double-well potential for copper cations as well as three-well potential for indium cations inside the structural layers. The temperature dependence of the spatial distribution of Cu+ and In3+ cations is also described within the quantum anharmonic oscillator model. In3+ cations play a decisive role in the character of the polar ordering: at ambient or for positive pressures, the first order transition occurs; with the rise of negative compression, the ferrielectric transition evolves to the second order. The peculiarities of spontaneous polarization switching are related to the contributions of copper and indium cationic sublattices. [ABSTRACT FROM AUTHOR]