Conditions for the formation of a non-autonomous phase at the structural deformation of complex vanadium oxides

Received: 02.03.2018. Accepted: 10.04.2018. Published: 10.05.2018.A new previously unknown effect of a reversible transition from a singlephase system to a heterophase system containing a non-autonomous phase was observed during thermal and chemical deformations of the Zn2–2xCd2xV2O7 structure.The role of local symmetry in the formation of the non-autonomous phase is shown on the basis of X-ray diffraction studies in situ and a comparative crystal-chemical analysis of the structural deformations of isoform monoclinic solid solutions of zinc and copper pyrovanadates with zero volumetric thermal expansion.The work was supported by UB RAS (project 18-10-3-32)

Water Splitting on Multifaceted SrTiO3 Nanocrystals: Calculations of Raman Vibrational Spectrum

The financial support of M-ERA.net SunToChem project is greatly acknowledged by L.L.R. and Y.A.M. This paper is partly based upon COST (European Cooperation in Science and Technology) Action 18234 Short Term Scientific Mission. The support is greatly acknowledged by E.K. and V.K. The Institute of Solid State Physics, University of Latvia (Latvia) as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2. The computer resources were provided by the Stuttgart Supercomputing Center (HLRS project DEFTD 12939) and Latvian Super Cluster (LASC).Various photocatalysts are being currently studied with the aim of increasing the photocatalytic efficiency of water splitting for production of hydrogen as a fuel and oxygen as a medical gas. A noticeable increase of hydrogen production was found recently experimentally on the anisotropic faces (facets) of strontium titanate (SrTiO3, STO) nanoparticles. In order to identify optimal sites for water splitting, the first principles calculations of the Raman vibrational spectrum of the bulk and stepped (facet) surface of a thin STO film with adsorbed water derivatives were performed. According to our calculations, the Raman spectrum of a stepped STO surface differs from the bulk spectrum, which agrees with the experimental data. The characteristic vibrational frequencies for the chemisorption of water derivatives on the surface were identified. Moreover, it is also possible to distinguish between differently adsorbed hydrogen atoms of a split water molecule. Our approach helps to select the most efficient (size and shape) perovskite nanoparticles for efficient hydrogen/oxygen photocatalytic production. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.M-ERA.net SunToChem project; COST Action 18234 Short Term Scientific Mission; LRS project DEFTD 12939; the Institute of Solid State Physics, University of Latvia as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2

Water Splitting on Multifaceted SrTiO3 Nanocrystals: Computational Study

The financial support of M-ERA.NET2 Sun2Chem project is greatly acknowledged by E.K. Authors thank Dr. Marjeta Ma?ek Kr?manc and prof. Chi-Sheng Wu, for the fruitful discussions. The financial support of FLAG-ERA JTC project To2Dox is acknowledged by Y.A.M. This paper is based upon the work from COST Action 18234, supported by COST (European Cooperation in Science and Technology). The support is greatly acknowledged by Y.A.M. and V.K. The grant No. 1.1.1.2/VIAA/l/16/147 (1.1.1.2/16/I/001) under the activity of Post-doctoral research aid is greatly acknowledged by M.S. and D.B. The Institute of Solid State Physics, University of Latvia (Latvia) as the Centre of Excellence has received funding from the European Union?s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2 . The computer resources were provided by the Stuttgart Supercomputing Center (project DEFTD 12939) and Latvian Super Cluster (LASC).Recent experimental findings suggest that strontium titanate SrTiO3 (STO) photocatalytic activity for water splitting could be improved by creating multifaceted nanoparticles. To understand the underlying mechanisms and energetics, the model for faceted nanoparticles was created. The multifaceted nanoparticles’ surface is considered by us as a combination of flat and “stepped” facets. Ab initio calculations of the adsorption of water and oxygen evolution reaction (OER) intermediates were performed. Our findings suggest that the “slope” part of the step showed a natural similarity to the flat surface, whereas the “ridge” part exhibited significantly different adsorption configurations. On the “slope” region, both molecular and dissociative adsorption modes were possible, whereas on the “ridge”, only dissociative adsorption was observed. Water adsorption energies on the “ridge” (−1.50 eV) were significantly higher than on the “slope” (−0.76 eV molecular; −0.83 eV dissociative) or flat surface (−0.79 eV molecular; −1.09 eV dissociative). © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Published under the CC BY 4.0 license.M-ERA.NET2 Sun2Chem; FLAG-ERA JTC project To2Dox; COST Action 18234; Post-doctoral research grant No. 1.1.1.2/VIAA/l/16/147 (1.1.1.2/16/I/001); Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2

First Principles Calculations of Hydrogen Evolution Reaction and Proton Migration on Stepped Surfaces of SrTiO3

The financial support of FLAG-ERA JTC project To2Dox is acknowledged by Y.M., G.Z., and E.K. This paper is based upon the work from COST Action 18234, supported by COST (European Cooperation in Science and Technology). The support is greatly acknowledged by Y.M., V.K., and K.S.E. The grant No. 1.1.1.2/VIAA/l/16/147 (1.1.1.2/16/I/001) under the activity of Post-doctoral research aid is greatly acknowledged by M.S. and D.B. K.S.E. acknowledges funding by the Ministry of Culture and Science of the Federal State of North Rhine-Westphalia (NRW Return Grant). K.S.E. is associated with the CRC/TRR247: “Heterogeneous Oxidation Catalysis in the Liquid Phase” (Project number 388390466-TRR 247), the RESOLV Cluster of Excellence, funded by the Deutsche Forschungsgemeinschaft under Germany’s Excellence Strategy – EXC 2033 – 390677874 – RESOLV, and the Center for Nanointegration (CENIDE). Authors thank Dr. Marjeta Maˇcek Kržmanc and Prof. Chi-Sheng Wu, for the fruitful discussions. The Institute of Solid State Physics, University of Latvia (Latvia) as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2. The computer resources were provided by the Stuttgart Supercomputing Center (project DEFTD 12939) and Latvian Super Cluster (LASC). Open access funding enabled and organized by Projekt DEAL.Recent research suggests that photocatalytic activity toward water splitting of strontium titanate SrTiO3 (STO) is enhanced by creating multifaceted nanoparticles. To better understand the source of this activity, a previously designed model is used for two types of surfaces of this nanoparticle, flat and double-stepped. Density functional theory calculations of water adsorption on these surfaces are performed to gain insight into water adsorption and proton migration processes, as well as thermodynamics of hydrogen evolution reaction within the framework of computational hydrogen electrode. It is concluded that ridges of single- and double-stepped surfaces are nearly identical in terms of adsorption configurations and energetics. Also, it is demonstrated that protons have migration barriers lower than 0.7 eV and that surface morphology impacts catalytic activity toward hydrogen evolution reaction, with flat surface demonstrating higher catalytic activity. --//-- This is an open access article Sokolov, M., Mastrikov, Y. A., Zvejnieks, G., Bocharov, D., Krasnenko, V., Exner, K. S., Kotomin, E. A., First Principles Calculations of Hydrogen Evolution Reaction and Proton Migration on Stepped Surfaces of SrTiO3. Adv. Theory Simul. 2023, 6, 2200619. https://doi.org/10.1002/adts.202200619 published under the CC BY-NC-ND licence.FLAG-ERA JTC project To2Dox; COST Action 18234, supported by COST (European Cooperation in Science and Technology); The grant No. 1.1.1.2/VIAA/l/16/147 (1.1.1.2/16/I/001) under the activity of Post-doctoral research aid; the Ministry of Culture and Science of the Federal State of North Rhine-Westphalia (NRW Return Grant); CRC/TRR247: “Heterogeneous Oxidation Catalysis in the Liquid Phase” (Project number 388390466-TRR 247), the RESOLV Cluster of Excellence, funded by the Deutsche Forschungsgemeinschaft under Germany’s Excellence Strategy – EXC 2033 – 390677874 – RESOLV, and the Center for Nanointegration (CENIDE); The Institute of Solid State Physics, University of Latvia (Latvia) as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2

Рецидивирующий полихондрит, развившийся после пирсинга (клинический случай)

Relapsing polychondritis (RPC) belongs to a group of rare rheumatic diseases with poorly understood etiology and pathogenesis. It is based on progressive systemic inflammatory damage to the cartilage tissue, primarily affecting ears, nose, trachea and bronchi. A standardized approach for the treatment of RPC has not yet been developed, so the treatment tactics are individualized for each patient.We describe a clinical case of a 39-year-old patient, who developed RPC after piercing the cartilaginous part of the ear. The components of the alloy used for the piercing could presumably serve as adjuvants and cause the development of a disease similar to ASIA syndrome (Autoimmune/Inflammatory Syndrome Induced by Adjuvants) with inflammation of the cartilage of the nose and ears. Possible pathogenetic mechanisms are presented, as well as diagnostic criteria for ASIA syndrome.Рецидивирующий полихондрит (РПХ) относится к группе редких ревматических заболеваний с недостаточно изученными этиологией и патогенезом. В его основе лежит прогрессирующее системное воспалительное поражение хрящевой ткани с преимущественным вовлечением ушных раковин, носа, трахеи и бронхов. Унифицированного подхода к лечению РПХ не разработано, поэтому тактика ведения каждого пациента индивидуальна.Описан случай развития РПХ у 39-летней пациентки после пирсинга хрящевой части ушной раковины. Компоненты сплава, использовавшегося для пирсинга, предположительно могли послужить адъювантами и спровоцировать развитие заболевания, сходного с синдромом ASIA (аутоиммунный/воспалительный синдром, индуцированный адъювантами) с воспалением хрящей носа и ушных раковин. Представлены возможные патогенетические механизмы, а также диагностические критерии синдрома ASIA

Experimental and theoretical investigations of the near-ground propagation of acoustic radiation in the atmosphere

Near-ground propagation of monochromatic acoustic radiation at frequencies of 300, 1000, 2000, and 3150 Hz along atmospheric paths up to 100 m long is investigated experimentally and theoretically depending on altitudes of the acoustic source and receiver. The experiment was carried out at the experimental site of the Institute of Monitoring of Climatic and Ecological Systems (IMCES) using a specially developed setup. The dependence of the recorded sound pressure level on the propagation path length and initial signal power is analyzed. The theoretical analysis is performed by the Monte Carlo method using the local estimation algorithm developed by the authors. The comparison of the experimental and theoretical results shows their satisfactory agreement, which indicates the effectiveness of the proposed algorithm and its applicability to predicting the near-ground sound propagation

Modeling of the Lattice Dynamics in Strontium Titanate Films of Various Thicknesses: Raman Scattering Studies

This paper is partly based upon COST (European Cooperation in Science and Technology) Action 18234 (E.A.K., M.S., and V.K.) and financially supported by FLAG-ERA JTC project To2Dox (Y.A.M). The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2. The computer resources were provided by the High-Performance Computing Centre Stuttgart (HLRS project DEFTD 12939). In addition, the research of V.K. and A.P. was partly supported by the RADON project (GA 872494) within the H2020-MSCA-RISE-2019 call.While the bulk strontium titanate (STO) crystal characteristics are relatively well known, ultrathin perovskites’ nanostructure, chemical composition, and crystallinity are quite complex and challenging to understand in detail. In our study, the DFT methods were used for modelling the Raman spectra of the STO bulk (space group I4/mcm) and 5–21-layer thin films (layer group p4/mbm) in tetragonal phase with different thicknesses ranging from ~0.8 to 3.9 nm. Our calculations revealed features in the Raman spectra of the films that were absent in the bulk spectra. Out of the seven Raman-active modes associated with bulk STO, the frequencies of five modes (2Eg, A1g, B2g, and B1g) decreased as the film thickness increased, while the low-frequency B2g and higher-frequency Eg modes frequencies increased. The modes in the films exhibited vibrations with different amplitudes in the central or surface parts of the films compared to the bulk, resulting in frequency shifts. Some peaks related to bulk vibrations were too weak (compared to the new modes related to films) to distinguish in the Raman spectra. However, as the film thickness increased, the Raman modes approached the frequencies of the bulk, and their intensities became higher, making them more noticeable in the Raman spectrum. Our results could help to explain inconsistencies in the experimental data for thin STO films, providing insights into the behavior of Raman modes and their relationship with film thickness. © 2023 by the authors. --//-- Krasnenko V., Platonenko A., Liivand A., Rusevich L.L., Mastrikov Y.A., Zvejnieks G., Sokolov M., Kotomin E.A.; Modeling of the Lattice Dynamics in Strontium Titanate Films of Various Thicknesses: Raman Scattering Studies; (2023) Materials, 16 (18), art. no. 6207; DOI: 10.3390/ma16186207; https://www.scopus.com/inward/record.uri?eid=2-s2.0-85172725318&doi=10.3390%2fma16186207&partnerID=40&md5=32f343f9cb8da145c6647566cb534c32. Published under the CC BY 4.0 license.COST Action 18234 and FLAG-ERA JTC project To2Dox. The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2. HLRS project DEFTD 12939. RADON project (GA 872494) within the H2020-MSCA-RISE-2019 call

Анкилозирующий спондилит в сочетании с комбинированным аутовоспалительным поражением кожи (клиническое наблюдение и обзор литературы)

We present a clinical case of combination of axial spondyloarthritis (axSpA) and chronic recurrent skin lesions in the form of acne conglobata, hidradenitis suppurativa (HS) with fistulous tracts formation. During the diagnostic search, the following diseases were considered: HS, SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, osteitis), PASS syndrome (pyoderma gangrenosum, acne, ankylosing spondylitis, HS). The choice of therapy in this patient and the possibility of using biologic disease-modifying antirheumatic drugs for axSpa and concomitant autoinflammatory skin process are discussed.Представлено клиническое наблюдение, в котором имелось сочетание аксиального спондилоартрита (аксСпА) и хронического рецидивирующего поражения кожи в виде конглобатных акне, гнойного гидраденита (ГГ) с формированием свищевых ходов. В ходе диагностического поиска рассматривались следующие заболевания: ГГ, синдром SAPHO (синовит, акне, пустулез, гиперостоз, остеит), PASS-синдром (гангренозная пиодермия, акне, анкилозирующий спондилит, ГГ). Обсуждаются выбор терапии у данного пациента и возможности использования генно-инженерных биологических препаратов при аксСпа и сопутствующем аутовоспалительном кожном процессе

Клинические особенности анкилозирующего спондилита у пациентов с вторичным АА-амилоидозом

Renal AA amyloidosis is the most severe type of renal pathology in patients with ankylosing spondylitis (AS). The characteristic symptoms of AA amyloidosis in rheumatic diseases do not often occur for years, making it difficult to diagnose it early and to start adequate therapy.Objective: to identify the clinical features of AS complicated by secondary AA amyloidosis.Patients and methods. The investigation enrolled 9 patients with AS (according to the 1984 modified New York criteria) and histologically confirmed secondary AA amyloidosis (Group 1). A comparison group included 216 AS patients without amyloidosis (Group 2).Results and discussion. In Group 1 patients, the age at the onset of AS was significantly less and the disease duration was 4 times longer than those in Group 2. All the patients with AA amyloidosis had enthesitis and arthritis, including those of the hip joints. The scores of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP), and the acute phase inflammation index CRP were higher in Group 1 than in Group 2.Conclusion. The clinical feature of AS complicated by secondary AA-amyloidosis is the long duration of the disease and the high frequency of juvenile onset, non-axial manifestations (arthritis, coxitis and enteritis), as well as the high activity of systemic inflammation.Почечный АА-амилоидоз – самый тяжелый тип патологии почек у пациентов с анкилозирующим спондилитом (АС). Нередко характерные симптомы АА-амилоидоза при ревматических заболеваниях не проявляются годами, затрудняя его раннюю диагностику и начало адекватной терапии.Цель исследования – выявление особенностей клинической картины АС, осложненного вторичным АА-амилоидозом.Пациенты и методы. В исследование включено 9 больных АС (согласно модифицированным Нью-Йоркским критериям, 1984) с гистологически подтвержденным вторичным АА-амилоидозом (1-я группа). Во 2-ю группу (группа сравнения) вошли 216 пациентов с АС без амилоидоза.Результаты и обсуждение. У пациентов 1-й группы возраст дебюта АС был значительно меньше, а длительность болезни – в 4 раза больше, чем у больных 2-й группы. Все больные с АА-амилоидозом имели энтезит и артрит, в том числе тазобедренных суставов. Индексы BASDAI и ASDAS-СРБ, а также острофазовый показатель воспаления – СРБ – у пациентов с АА-амилоидозом были выше, чем в группе сравнения.Заключение. Особенностью клинической картины АС, осложненного вторичным АА-амилоидозом, являются большая длительность заболевания и высокая частота ювенильного начала, внеаксиальных проявлений (артрит, коксит и энтезит), а также высокая активность системного воспаления