Due to continuous aging of population and increase in the number of elderly people, osteoporosis became socially significant disease leading to disability, increasing mortality and thereby putting an additional burden on the public healthcare system.Screening to identify groups with a high probability of fracture is recommended using the FRAX^®Tool for all postmenopausal women and men over 50 years old (А1). In the presense of major pathological fractures (hip, spine, multiple fractures) it is recommended to diagnose osteoporosis and prescribe treatment regardless of the results of spine and hip double X-ray absorptiometry (DXA) or FRAX^®(B2).It is recommended to evaluate C-terminal telopeptide when prescribing antiresorptive therapy and procollagen type 1 N-terminal propeptide (P1NP) when prescribing anabolic therapy to patients receiving osteoporosis treatment at baseline and 3 months after the start of therapy in order to assess the effectiveness of treatment early and adherence to the therapy (А2). It is recommended to diagnose osteoporosis and prescribe treatment to patients with high individual 10-year probability of major pathological fractures (FRAX^®) regardless of the results of spine and hip DXA (В3).It is recommended to diagnose osteoporosis and prescribe treatment with a decrease in BMD, measured by DXA, by 2.5 or more T-score standard deviations in femoral neck, and/or in total hip, and/or in lumbar vertebrae, in postmenopausal women and men over 50 years old (А2).It is recommended to prescribe bisphosphonates, denosumab or teriparatide to prevent pathological fractures and increase BMD in patients with postmenopausal osteoporosis, osteoporosis in men, glucocorticoid-induced osteoporosis (А2). When the clinical effect of therapy in osteoporotic patients without pathological fractures is achieved (BMD T-score > -2.0 SD in femoral neck and absence of new fractures), it is recommended to interrupt bisphosphonates therapy for 1-2 years with subsequent follow-up (B2). In patients with vertebral fractures, hip fractures or multiple fractures, it is recommended to continue ceaseless long-term treatment of osteoporosis (В3).All drugs for the treatment of osteoporosis are recommended to be prescribed in combination with calcium and cholecalciferol (А2). In order to reduce the risk of recurrent fractures by prescribing osteoporosis therapy timely and maintaining long-term follow-up of patients over 50 years old with pathological fractures, it is recommended to create Fracture Liaison Services (В2).

A summary of the draft federal clinical guidelines on osteoporosis developed by members of the Russian Association of Endocrinologists, the Russian Association for Osteoporosis, the Association of Rheumatologists of Russia, the Association of Traumatologists and Orthopedists of Russia, the Russian Association for Menopause and the Russian Association of Gerontologists and Geriatrics is presented. The recommendations were developed from the perspective of evidence-based medicine, in accordance with the requirements for compiling clinical recommendations of the Ministry of Health of Russia published in 2019. A significant place is given to screening of primary osteoporosis in adults, differential diagnosis with other metabolic diseases of the skeleton, modern methods of diagnosing osteoporosis, principles of prescribing pathogenetic treatment, features of sequential and combination therapy, disease prevention and rehabilitation. Clinical recommendations will be useful both to general practitioners and physicians, as well as to narrow specialists, primarily endocrinologists, rheumatologists, orthopedic traumatologists, nephrologists, obstetrician-gynecologists and neurologists, since osteoporosis is a multifactorial and multidisciplinary disease.

Inorganic materials with layered perovskite structures have a wide range of physical and chemical properties. Layered perovskites based on BaLa_nIn_nO_3n+1 (n = 1, 2) were recently investigated as protonic conductors. This work focused on the oxygen ion and proton transport (ionic conductivity and mobility) in alkali-earth (Sr²⁺, Ba²⁺)-doped layered perovskites based on BaLa₂In₂O₇. It is shown that in the dry air conditions, the nature of conductivity is mixed oxygen–hole, despite the dopant nature. Doping leads to the increase in the conductivity values by up to ~1.5 orders of magnitude. The most proton-conductive BaLa_1.7Ba_0.3In₂O_6.85 and BaLa_1.7Sr_0.15In₂O_6.925 samples are characterized by the conductivity values 1.2·10⁻⁴ S/cm and 0.7·10⁻⁴ S/cm at 500 °C under wet air, respectively. The layered perovskites with Ruddlesden-Popper structure, containing two layers of perovskite blocks, are the prospective proton-conducting materials and further material science searches among this class of materials is relevant.

The design of new oxide compounds that can be used as oxygen- or proton-conducting electrolytes for solid oxide fuel cells is actively in progress. Despite the intensive research activities regarding electrolytes with perovskite/fluorite structures, the search for other structural alternatives is of paramount importance. In this study we focus on a novel material with significantly improved properties for the electrochemical purposes. The two-layered BaNd₂In₂O₇ perovskite with a Ruddlesden–Popper structure was investigated as a protonic conductor for the first time. In detail, its local structure, water uptake, and the ionic (O²⁻, H⁺) conductivity were comprehensively studied. The nature of rare-earth elements (M = La, Nd) in the structure of BaM₂In₂O₇ on the structural and transport properties was revealed. The presented analysis showed that the composition of BaNd₂In₂O₇ is nearly pure proton conductor below 350 °C. This work opens up a new way in the design of protonic conductors with double-layered perovskite structure.

This paper demonstrates the possibility of creating oxygen deficiency in perovskites A⁺³B⁺³O₃ by introducing two types of cations with different charges into the B-sublattice. For this, it is proposed to introduce a two-charged cation, for example, Zn²⁺, as an alternative to alkaline earth metals. Previously, this possibility was demonstrated for aluminate LaAlO₃ and indate LaInO₃. In this article, we have focused on the modification of the scandium-containing perovskite LaScO₃. The novel oxygen-deficient perovskite La₂ScZnO_5.5 and doped phases La_1.9Ca_0.1ScZnO_5.45, La₂Sc_0.9Ca_0.1ZnO_5.45, and La₂Sc_0.9Mg_0.1ZnO_5.45 were obtained via a solid-state reaction process. Their phase composition and hydration were investigated by XRD and TGA + MS techniques. The conductivities of these materials were measured by the electrochemical impedance technique under atmospheres of various water vapor partial pressures. All phases crystallized in orthorhombic symmetry with the Pnma space group. The phases were capable of reversible water uptake; the proton concentration increased in the order of La₂ScZnO_5.5 < La₂Sc_0.9Mg_0.1ZnO_5.45 < La₂Sc_0.9Ca_0.1ZnO_5.45 ≈ La_1.9Ca_0.1ScZnO_5.45 and reached ~90% hydration limit for Ca²⁺-doped phases. The total conductivities increased with the increase in the free lattice volume in the sequence of σLa₂ScZnO_5.5 < σLa₂Sc_0.9Mg_0.1ZnO_5.45 < σLa_1.9Ca_0.1ScZnO_5.45 < σLa₂Sc_0.9Ca_0.1ZnO_5.45, the activation energy decreased in the same sequence. The sample La₂Sc_0.9Ca_0.1ZnO_5.45 showed the highest conductivity of about 10⁻³ S∙cm⁻¹ at 650 °C (dry air pH₂O = 3.5·10⁻⁵ atm). Water incorporation was accompanied by an increase in conductivity in wet air (pH₂O = 2·10⁻² atm) due to the appearance of proton conductivity. The sample La₂Sc_0.9Ca_0.1ZnO_5.45 showed a conductivity of about 10⁻⁵ S∙cm⁻¹ at 350 °C (pH₂O = 2·10⁻² atm). A comparison of conductivities of obtained phase La₂ScZnO_5.5 with the conductivities of La₂AlZnO_5.5 and La₂InZnO_5.5 was made; the nature of the B-cation did not significantly affect the total conductivity.

The tasks of quality environmental improvement and the development of new energy sources are very relevant. Hydrogen-operating electrochemical devices are strongly needed innovative ceramic materials with target properties, one of which is a high level of proton conductivity. It this paper, the possibility of proton conductivity in acceptor-doped two-layer compositions based on BaLa₂In₂O₇ was proved for the first time. It was proved that doping leads to an increase in conductivity values up to ~1.5 orders of magnitude. The most conductive is the BaLa_1.9Sr_0.1In₂O_6.95 composition which demonstrates protonic conductivity value 2 × 10^–5 S/cm at 450 °C. The acceptor-doped two-layer perovskites is a novel prospective class of proton-conducting materials, and further modification of their composition opens up a new method for the design of electrochemical energy generation devices.