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Martin Hýža,1,2 Petr Šilhán,1,2 Eva Češková,1,2 Tomáš Skřont,1 Ivana Kacířová,3,4 Romana Uřinovská,3 Milan Grundmann4 1Department of Psychiatry, University Hospital Ostrava, Ostrava, Czech Republic; 2Department of Clinical Neurosciences, Faculty of Medicine, University of Ostrava, Ostrava, Czech Republic; 3Department of Clinical Pharmacology, Institute of Laboratory Diagnostics, University Hospital Ostrava, Ostrava, Czech Republic; 4Department of Clinical Pharmacology, Faculty of Medicine, University of Ostrava, Ostrava, Czech RepublicCorrespondence: Petr ŠilhánDepartment of Psychiatry, University Hospital Ostrava, 17. Listopadu 1790, Ostrava, 708 52, Czech RepublicTel +420 59 737 3145Fax +420 59 737 3314Email petr.silhan@fno.czPurpose: Antipsychotic efficacy in schizophrenia depends on its availability in the body. Although therapeutic outcomes remain still far from satisfactory, therapeutic drug monitoring is not a common part of clinical practice during treatment with long-acting injectable antipsychotics (LAI AP). The real effectiveness of LAI AP is thus uncertain.Patients and Methods: We made a retrospective evaluation of plasma levels of LAI AP. Collection of blood samples was performed just before the drug application and one week later. Forty patients with a stabilized clinical condition and steady-state plasma levels were included.Results: In the observed cohort of patients, flupentixol decanoate (n = 23) was the most often used drug, followed by fluphenazine decanoate (n = 7), haloperidol decanoate (n = 5), paliperidone palmitate (n = 3), and risperidone microspheres (n = 2). Just 5 of 40 patients were treated with a monotherapy. In the period before the application, 60% of the patients did not reach the therapeutic reference range (TRR) and 20% of the patients had an undetectable plasma level. At the time of collection of the second blood samples performed after 7 days, 24% of the patients were under the TRR.Conclusion: We have found a surprisingly high incidence of plasma levels under the TRR in patients treated with LAI AP. Notwithstanding individual variability in pharmacokinetics, it seems that LAI AP may be underdosed in usual clinical practice.Keywords: therapeutic drug monitoring, antipsychotics, psychotic disorders, schizophrenia

Novel devices based on orthorhombic κ - Ga 2 O 3 could enable solar blind infrared detection or high-electron mobility transistors with large two-dimensional electron gas densities. Here, we report on the current transport parallel to the growth direction of κ - Ga 2 O 3 layers grown by pulsed-laser deposition on highly conductive Al-doped ZnO back contact layers. Besides ohmic Ti/Al/Au contact layer stacks, vertical Pt / PtO x / κ - Ga 2 O 3 and Pd / PdO x / κ - Ga 2 O 3 Schottky barrier diodes and NiO / κ - Ga 2 O 3 and ZnCo 2 O 4 / κ - Ga 2 O 3 p n -heterodiodes are investigated by current–voltage measurements. While a lateral current transport is severely suppressed to less than 10 − 9 A cm − 2 due to rotational domains, we record a significant current flow through the ohmic contacts in the vertical direction of > --> 0.1 A cm − 2 . The Schottky barrier diodes and the p n -heterojunctions exhibit rectification ratios of up to seven orders of magnitude. Room temperature current–voltage characteristics of diode ensembles as well as temperature-dependent measurements for selected Pt-based diodes reveal a mean barrier height of ϕ B m ≈ 2.1 eV and ideality factors down to η ≈ 1.3. [ABSTRACT FROM AUTHOR]

Single-crystalline Zn3N2 thin films have been grown on MgO (100) and YSZ (100) substrates by plasma-assisted molecular beam epitaxy. Depending on growth conditions, the film orientation can be tuned from (100) to (111). For each orientation, x-ray diffraction and reflection high-energy electron diffraction are used to determine the epitaxial relationships and to quantify the structural quality. Using high-temperature x-ray diffraction, the Zn3N2 linear thermal expansion coefficient is measured with an average of (1.5 ± 0.1) × 10−5 K−1 in the range of 300–700 K. The Zn3N2 films are found to be systematically n-type and degenerate, with carrier concentrations of 1019–1021 cm−3 and electron mobilities ranging from 4 to 388 cm2 V−1 s−1. Low-temperature Hall effect measurements show that ionized impurity scattering is the main mechanism limiting the mobility. The large carrier densities lead to measured optical bandgaps in the range of 1.05–1.37 eV due to Moss–Burstein band filling, with an extrapolated value of 0.99 eV for actual bandgap energy. [ABSTRACT FROM AUTHOR]

We present a systematic study of the magnetic properties of ZnFe2O4 thin films fabricated by pulsed laser deposition at low and high oxygen partial pressure and annealed in oxygen and argon atmosphere, respectively. The as-grown films show strong magnetization, closely related to a non-equilibrium distribution of defects, namely, Fe cations among tetrahedral and octahedral lattice sites. While the concentration of tetrahedral Fe cations declines after argon treatment at 250 °C, the magnetic response is enhanced by the formation of oxygen vacancies, evident by the increase in near-infrared absorption due to the Fe2+–Fe3+ exchange. After annealing at temperatures above 300 °C, the weakened magnetic response is related to a decline in disorder with a partial recrystallization toward a less defective spinel configuration. [ABSTRACT FROM AUTHOR]

Schottky barrier diodes on α − Ga 2 O 3 :Sn heteroepitaxial thin films grown by pulsed laser deposition on m-plane sapphire substrates are reported. Sets of co-planar diodes were fabricated with different metals and different deposition methods. The current rectification and effective Schottky barrier height of oxidized contacts realized by reactive sputtering significantly exceed the values of non-oxidized contacts realized by thermal evaporation or sputtering in an inert argon atmosphere. The best values obtained are rectification of about eight orders of magnitude (± 2 V) and 1.3 eV effective barrier height. The current-voltage characteristics of selected non-oxidized and oxidized platinum diodes have been studied as a function of measurement temperature. The temperature dependence of the effective barrier height and the ideality factor of the diodes were fitted taking into account the lateral potential fluctuations of the barrier potential. The determined mean barrier heights and standard deviations are in the range of 1.76–2.53 and 0.2–0.33 eV, respectively, and are classified with respect to the literature and fulfill a well-established empirical correlation (Lajn's rule) for a variety of Schottky barrier diodes on different semiconducting materials. [ABSTRACT FROM AUTHOR]

The last missing piece of the puzzle for the full functionalization of group IV optoelectronic devices is a direct bandgap semiconductor made by CMOS compatible technology. Here, we report on the fabrication of GeSn alloys with Sn concentrations up to 4.5% using ion implantation followed by millisecond-range explosive solid phase epitaxy. The n-type single crystalline GeSn alloys are realized by co-implantation of Sn and P into Ge. Both the activation of P and the formation of GeSn are performed during a single-step flash lamp annealing for 3 ms. The bandgap engineering in GeSn as a function of the doping level and Sn concentration is theoretically predicted by density functional theory and experimentally verified using ellipsometric spectroscopy. We demonstrate that both the diffusion and the segregation of Sn and P atoms in Ge are fully suppressed by millisecond-range nonequilibrium thermal processing. [ABSTRACT FROM AUTHOR]

A method for the evaluation of experimental data from spectroscopic ellipsometry is proposed which combines the global-search optimization algorithm with statistical model selection criteria. The hybrid genetic-gradient search algorithm (HGGA) is applied to find the optical parameters and thickness of a diamond-like carbon (DLC) coating deposited on SW7M stainless steel. Akaike and Bayesian information criteria are used to evaluate the different dielectric function models. The method is able to find optical model parameters even in case of a limited initial knowledge about the material optical constants. At the same time, the optimal dielectric function model for the description of the material optical properties can be selected unambiguously from the set of candidate models. [ABSTRACT FROM AUTHOR]

The article studies the current-voltage mechanism of low-ideality factor ZnO Schottky diodes over temperature range of 40-423 K. Findings revealed that TE was a major current transport mechanism at RT and above.

A comprehensive study on growth of ferrimagnetic manganese zinc ferrite (Mn0.5Zn0.5Fe2O4) films on single crystalline strontium titanate(001) (SrTiO3) substrates was carried out. Under the optimized conditions, a thin film with a layer thickness of 200 nm was deposited, and the structural properties were investigated. Contrary to data published in literature, no buffer layer was necessary to achieve epitaxial growth of a poorly lattice-matched layer. This was confirmed for Mn0.5Zn0.5Fe2O4(001) on SrTiO3(001) by x-ray diffraction and the adjoined phi scans, which also revealed a lattice compression of 1.2% of the manganese zinc ferrite film in the out-of-plane direction. Using x-ray photoelectron spectroscopy, the near surface stoichiometry of the film could be shown to agree with the intended one within the uncertainty of the method. X-ray absorption spectroscopy showed an electronic structure close to that published for bulk samples. Additional x-ray magnetic circular dichroism investigations were performed to answer detailed structural questions by a comparison of experimental data with the calculated ones. The calculations took into account ion sites (tetrahedral vs. octahedral coordination) as well as the charge of Fe ions (Fe2+ vs. Fe3+). Contrary to the expectation for a perfect normal spinel that only Fe3+ ions are present in octahedral sites, hints regarding the presence of additional Fe2+ in octahedral sites as well as Fe3+ ions in tetrahedral sites have been obtained. Altogether, the layer could be shown to be mostly in a normal spinel configuration. [ABSTRACT FROM AUTHOR]