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1.
ACS Appl Mater Interfaces ; 16(6): 7430-7443, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38299992

RESUMO

Self-assembly gives rise to the versatile strategies of smart material design but requires precise control on the supramolecular level. Here, inorganic-organic synthons (conjugates) are produced by covalently grafting stearic acid tails to giant polyoxometalate (POM) Keplerate-type {Mo132} through an organosilicon linker (3-aminopropyltrimethoxysilane, APTMS). Using the liposome production approach, the synthons self-assemble to form hollow nanosized vesicles (100-200 nm in diameter), which can be loaded with organic dyes─eriochrome black T (ErChB) and fluorescein (FL)─where the POM layer serves as a membrane with subnanopores for cell-like communication. The dye structure plays an essential role in embedding dyes into the vesicle's shell, which opens the way to control the colloidal stability of the system. The produced vesicles are moved by an electric field and used for the creation of an infochemistry scheme with three types of logic gates (AND, OR, and IMP). To design 2D materials, synthons can form spread films, from simple addition on the water-air interface to lateral compression in the Langmuir bath, and highly ordered structures appear, demonstrating electron diffraction in Langmuir-Schaefer (LS) films. These results show the significant potential of POM-based synthons and nanosized vesicles to supramolecular design the diversity of smart materials.

2.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36361604

RESUMO

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 BaLa1.9Sr0.1In2O6.95 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.


Assuntos
Compostos de Cálcio , Prótons , Estudos Prospectivos , Cerâmica
3.
Materials (Basel) ; 15(10)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35629516

RESUMO

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.

4.
Materials (Basel) ; 14(21)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34771766

RESUMO

This work focused on the novel electrochemical energy material with significantly improved electrical properties. The novel complex oxide Ba1.1La0.9In0.5Y0.5O3.95 with layered perovskite structure was obtained for the first time. It was proven that the simultaneous introduction of barium and yttrium ions in the structure of BaLaInO4 leads to the increase in the unit cell volume of up to 4% and water uptake by about three times. The increase in the proton conductivity values was both due to an increase in the proton concentration and their mobility. The sample Ba1.1La0.9In0.5Y0.5O3.95 was a nearly pure proton conductor below 400 °C. The co-doping strategy allowed us to increase the protonic conductivity values up to two orders of magnitude and it is the successful method for the design of novel protonic conductors based on the layered perovskites.

5.
Dalton Trans ; 50(31): 10935-10946, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34318846

RESUMO

A new series of Ba2RE2Ge4O13 (RE = Pr, Nd, Gd, Dy) germanates and Ba2Gd2-xEuxGe4O13 (x = 0.1-0.8) solid solutions have been synthesized using the solid-state reaction technique and characterized by X-ray powder diffraction. All compounds crystallize in the monoclinic system, space group C2/c, Z = 4. The crystal lattice consists of RE2O12 dimers, zigzag C2-symmetric [Ge4O13]10- tetramers, and ten-coordinated Ba atoms located in voids between polyhedra. The density-functional theory (DFT) calculations performed on a rich set of Ba2RE2Ge4O13 compounds have confirmed the high thermodynamic stability of monoclinic modification. Under ultraviolet (UV) light excitation Ba2Gd2-xEuxGe4O13 phosphors exhibit an orange-red emission corresponding to the characteristic f-f transitions in Eu3+ ions. The highest intensity of lines at 580 nm (5D0→7F0), 582-602 nm (5D0→7F1), 602-640 nm (5D0→7F2), 648-660 nm (5D0→7F3), and 680-715 nm (5D0→7F4) is observed for the samples with x = 0.4-0.6. The possibility of their application has been assessed by studying their color characteristics, quantum efficiency, and thermal stability. The obtained data indicate that Ba2Gd2-xEuxGe4O13 solids can be considered as promising materials for UV-excited phosphor-converted light-emitting diodes (LEDs) if an aluminum nitride substrate (λex = 255 nm) is used as a semiconductor chip.

6.
Arch Osteoporos ; 15(1): 184, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219455

RESUMO

A retrospective cohort study determined the high incidence of recurrent fractures in osteoporotic patients with high fracture risk during the observation. The strategy of starting treatment with more potent regimens (zoledronic acid, denosumab and/or teriparatide) seems to have the best secondary fracture prevention efficacy. OBJECTIVE: This paper describes the various medical therapy regimens prescribed to osteoporotic patients with high fracture risk and the result of treatment. METHODS: We carried out a retrospective cohort study in selected Osteoporosis Centers. Patients were considered to have high fracture risk in case of a history of a low-energy hip fracture or two or more vertebral or other site fractures. A total of 812 subjects (768 women and 44 men) aged 36-95 years were included. The observation period was 2285.1 patient-years. Demographic data, clinical findings, and BMD data obtained by DXA, as well as a history of fractures that had occurred during the follow-up, were included in the analysis. RESULTS: Overall, at baseline, there were 637 non-vertebral fractures including 104 hip fractures. A total of 590 patients had vertebral fractures; of these, 69% suffered multiple fractures. Being on treatment, 119 (14.7%) patients developed new vertebral and non-vertebral fractures. The incidence of new non-vertebral fractures and hip fractures was 39.4 and 13.1 per 1000 patient-years. The total number of vertebral fractures increased by 24.8% from 1353 to 1689. The best results of the treatment were achieved in patients who were started on zoledronic acid, denosumab, or teriparatide and had an adequate duration of treatment. Although these patients had significantly lower BMD values at the time of diagnosis compared with other patients, they showed a lower incidence of new vertebral and hip fractures, during the follow-up. CONCLUSION: Therapy of patients at high risk of fractures started with more potent treatment regimens (zoledronic acid, denosumab and/or teriparatide) of adequate duration was more effective in terms of prevention of new vertebral and hip fractures as compared with other treatment options. However, treatment appears to be challenging given the number of recurrent fractures in patients on treatment and the frequency of drug withdrawal or replacement.


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Estudos Retrospectivos , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/prevenção & controle , Teriparatida/uso terapêutico
7.
Arch Osteoporos ; 15(1): 37, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32124066

RESUMO

Changes in health-related quality of life (QoL) due to hip, humeral, ankle, spine, and distal forearm fracture were measured in Russian adults age 50 years or more over the first 18 months after fracture. The accumulated mean QoL loss after hip fracture was 0.5 and significantly greater than after fracture of the distal forearm (0.13), spine (0.21), proximal humerus (0.26), and ankle (0.27). INTRODUCTION: Data on QoL following osteoporotic fractures in Russia are scarce. The present study evaluated the impact of hip, vertebral, proximal humerus, distal forearm, and ankle fracture up to 18 months after fracture from the Russian arm of the International Costs and Utilities Related to Osteoporotic Fractures Study. METHODS: Individuals age ≥ 50 years with low-energy-induced humeral, hip, clinical vertebral, ankle, or distal forearm fracture were enrolled. After a recall of pre-fracture status, HRQoL was prospectively collected over 18 months of follow-up using EQ-5D-3L. Multivariate regression analysis was used to identify determinants of QALYs loss. RESULTS: At 2 weeks, patients with hip fracture (n = 223) reported the lowest mean health state utility value (HSUV) compared with other fracture sites. Thereafter, utility values increased but remained significantly lower than before fracture. For spine (n = 183), humerus (n = 166), and ankle fractures (n = 214), there was a similar pattern of disutility with a nadir within 2 weeks and a progressive recovery thereafter. The accumulated mean QoL loss after hip fracture was 0.5 and significantly greater than after fracture of the distal forearm (0.13), spine (0.21), proximal humerus (0.26), and ankle (0.27). Substantial impairment in self-care and usual activities immediately after fracture were important predictors of recovery across at all fracture sites. CONCLUSIONS: Fractures of the hip, vertebral, distal forearm, ankle, and proximal humerus incur substantial loss of QoL in Russia. The utility values derived from this study can be used in future economic evaluations.


Assuntos
Fraturas por Osteoporose/economia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Traumatismos do Tornozelo/economia , Traumatismos do Tornozelo/psicologia , Efeitos Psicossociais da Doença , Feminino , Traumatismos do Antebraço/economia , Traumatismos do Antebraço/psicologia , Fraturas do Quadril/economia , Fraturas do Quadril/psicologia , Humanos , Fraturas do Úmero/economia , Fraturas do Úmero/psicologia , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/psicologia , Anos de Vida Ajustados por Qualidade de Vida , Federação Russa/epidemiologia , Fraturas da Coluna Vertebral/economia , Fraturas da Coluna Vertebral/psicologia
8.
Dalton Trans ; 48(20): 6984-6996, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31044195

RESUMO

The process of adsorption of nitrogen monoxide and dioxide by the giant Keplerate nanocluster Mo72Fe30 was studied in detail under ambient conditions and air/argon atmosphere. The obtained Raman and IR spectra showed that the coordination of NOx to the Mo72Fe30 leads to the formation of nitrate ions by sharing the bridged or terminal oxygen in FeO6 polyhedra with the adsorbed NO2 molecules. In accordance with elemental analysis and X-ray photoelectron spectroscopy, the composition of the produced complex was found to be [POM-(NO2)x]·(NO2)y (where x = 6, y = 14 ± 3). The carried out thermal analysis revealed the significant influence of NOx coordination in the release of water molecules and decomposition of the constitutional acetate ligands for Mo72Fe30. Furthermore, the performed measurements of the temperature dependency of the electron paramagnetic resonance spectra for the pure nanocluster and that treated with NO2 allowed us to draw up a conclusion about the delocalization of weak-bonded NO2 molecules in the pores of the Mo72Fe30 crystal at 25 °C. The opposite situation was observed under cryogenic temperatures. The localization of NO2 molecules occurs resulting in the distortion of FeO6 octahedra towards tetrahedral symmetry accompanied with the appearance of the signal at g-factor 4.3. The produced complex compound [POM-(NO2)x]·(NO2)y possesses sufficient NO2 capacity, water solubility and pH-dependant decomposition; these are important properties of a potential NOx donor, which can be hypothetically applied in biomedicine.

9.
Arch Osteoporos ; 7: 67-73, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23225283

RESUMO

UNLABELLED: The incidence of hip, forearm and humeral fractures was studied in two cities from the Russian Federation. Fracture rates were used to create a FRAX model for Russia and to estimate the current and future burden of fracture. PURPOSE: There is scant information on the epidemiology of fracture in Russia. The aim of the study was to determine the incidence of major fractures in order to populate a new FRAX model and to characterise the burden and future burden of fractures. METHODS: The number of hip, forearm and humeral fractures was determined in two Russian cities with a well-defined catchment population over a 2-3-year period. Incidence rates for the two cities were merged and used to populate a FRAX model for Russia. Incidence rates were also applied to the general population in 2010 and 25 years later in 2035. RESULTS: A total of 6,012 fractures were documented. For hip fracture, 27 % of cases in Pervouralsk and 1.8 % in Yaroslavl were not registered in the hospital data base. The incidence of index fractures increased with age and was higher in women than in men. The lifetime probability of hip fracture at the age of 50 years was 4 % in men and 7 % in women. The total number of hip fractures estimated in 2010 (112,000) is expected to rise to 159,000 in 2035. The estimated number of major fractures will rise from 590,000 to 730,000 over the same time interval. CONCLUSIONS: Fragility fractures pose a serious health care problem in Russia. Urgent steps are needed to improve the acute management of hip fracture and long-term care of other osteoporotic fractures.


Assuntos
Fraturas do Quadril/epidemiologia , Úmero/lesões , Modelos Estatísticos , Osteoporose/epidemiologia , Fraturas do Rádio/epidemiologia , Fraturas da Ulna/epidemiologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Federação Russa/epidemiologia
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