Diagnostic and prognostic perspectives of fabry disease via fiber evanescent wave spectroscopy advanced by machine learning.

Fabry disease (FD) is a rare disorder resulting from a genetic mutation characterized by the accumulation of sphingolipids in various cells throughout the human body, leading to progressive and irreversible organ damage, particularly in males. Genetically-determined deficiency or reduced activity of the enzyme (alpha - Galactosidase; α-Gal) leads to the accumulation of sphingolipids in the lysosomes of various cell types, including the heart, kidneys, skin, eyes, central nervous system, and digestive system, triggering damage, leading to the failure of vital organs, and resulting in progressive disability and premature death. FD diagnostics currently depend on costly and time-intensive genetic tests and enzymatic analysis, often leading to delayed or inaccurate diagnoses, which contribute to rapid disease progression.

Radiation-induced modification effects in covalent-network glass formers: Phenomenological description within unified configuration-enthalpy model.

Externally-induced modification activated by high-energy excitation such as γ-irradiation from Co source is analyzed in chalcogenide glasses in terms of radiation-structural and glass-relaxation metastability, at the example of sulphides (including stoichiometric arsenic trisulphide, AsS) and selenides. Unified configuration-enthalpy model evolving conjugated configuration-coordinate (free energy in dependence on configuration coordinate) and thermodynamic enthalpy (temperature deviations in enthalpy, configurational entropy or free volume) diagrams is proposed to describe metastability in these glasses under external influences, such as (1) physical ageing, (2) irradiation, (3) thermal annealing, (4) rejuvenation, and their combinations. The model predicts glass stabilization in the ground state composed of partial sub-states related to (i) irradiation, (ii) rejuvenation, (iii) annealing, as well as (iv) ideal-glass deep states, connected by over-barrier jumping and through-barrier tunneling transitions.

Dynamics of structural relaxation in bioactive 45S5 glass.

Kinetics of physical aging in archetypic 45S5 bioactive silicate glass composition with different types of phase separation are studied in situ below the glass transition temperature (T ). The qualitative nature of aging is found to be almost independent of the structural differences on the micrometer scale. A well-expressed step-like behavior in the enthalpy recovery kinetics is observed for aging temperatures T ∼ 0.

Giant visible and infrared light attenuation effect in nanostructured narrow-bandgap glasses.

A unique effect of Bi on the optical and electrical properties of mixed Ga-containing Ge-Se and Ge-Te glasses is discovered. It is shown that glass with a low Bi content is completely transparent in a 3-16 μm spectral range, while the glass with a slightly higher Bi content possesses a large (>10  db/mm) attenuation coefficient, making a ∼millimeter thick glass sample fully opaque to VIS-IR radiation. Despite this contrast, both types of glass are found to retain their semiconducting properties, the DC conductivity at room temperature, σ∼10  S/m, being comparable to that of silicon.

Role of phase separation on the biological performance of 45S5 Bioglass.

We analyzed the biological performance of spinodally and droplet-type phase-separated 45S5 Bioglass generated by quenching the melt from different equilibrium temperatures. MC3T3-E1 pre-osteoblast cells attached more efficiently to 45S5 Bioglass® with spinodal than to the one with droplet morphology, providing the first demonstration of the role of micro-/nano-scale on the bioactivity of Bioglass®. Upon exposure to biological solutions, phosphate buffered saline (PBS) and cell culture medium (α-MEM), a layer of hydroxyapatite (HA) formed on both glass morphologies.

Crossover between cooperative and fractal relaxation in complex glass-formers.

Kinetics of physical aging at different temperatures is studied in situ in arsenic selenide glasses using high-precision differential scanning calorimetry technique. A well-expressed step-like behaviour in the enthalpy recovery kinetics is recorded for low aging temperatures. These fine features disappear when the aging temperature (T a) approaches the glass transition temperature (T g).

Study of Ga incorporation in glassy arsenic selenides by high-resolution XPS and EXAFS.

Effect of Ga addition on the structure of vitreous As2Se3 is studied using high-resolution X-ray photoelectron spectroscopy and extended X-ray absorption fine structure techniques. The "8-N" rule is shown to be violated for Ga atoms and, possibly, for certain number of As atoms. On the contrary, Se keeps its 2-fold coordination according to "8-N" rule in the amorphous phase throughout all the compositions.

Positronics of subnanometer atomistic imperfections in solids as a high-informative structure characterization tool.

Methodological possibilities of positron annihilation lifetime (PAL) spectroscopy applied to characterize different types of nanomaterials treated within three-term fitting procedure are critically reconsidered. In contrast to conventional three-term analysis based on admixed positron- and positronium-trapping modes, the process of nanostructurization is considered as substitutional positron-positronium trapping within the same host matrix. Developed formalism allows estimate interfacial void volumes responsible for positron trapping and characteristic bulk positron lifetimes in nanoparticle-affected inhomogeneous media.

Influence of phase separation on the devitrification of 45S5 bioglass.

The devitrification of the 45S5 variety of bioactive glasses (BGs) in relation to phase separation is studied with scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry and positron annihilation lifetime spectroscopy techniques. It is shown that the type of phase separation (such as spinodal vs. droplet-like) has a pronounced effect on the activation energy of viscous flow and crystallization, the onset temperature of crystallization and the void size distribution at the nanoscale.

Complex structural rearrangements in As-Se glasses.

Structural relaxation of As-Se glasses through the glass-to-supercooled liquid transition interval is studied with temperature-modulated differential scanning calorimetry. It is shown that connectivity of glass network and long-term physical ageing change not only the full width at half maximum of the out-of-phase component of complex heat capacity, which is conventionally used for analysis, but also its asymmetry value. The latter is shown to carry very important information on the dynamic heterogeneity in glasses.

Structural evolution of Ga-Ge-Te glasses by combined EXAFS and XPS analysis.

The structural evolution of GaxGeyTe100-x-y glasses in the vicinity of GeTe4-GaTe3 pseudo-binary tie-line is determined with high-resolution X-ray photoelectron (XPS) and extended X-ray absorption fine structure (EXAFS) spectroscopies. The analysis of XPS data is complicated by similar electronegativity values for the constituent chemical elements, but then the interpretation is facilitated by information from complementary EXAFS analysis of the structure around each element independently. The results show 4∕4∕2 coordination for Ga∕Ge∕Te atoms and absence of Ga(Ge)-Ge(Ga) bonds or extended Te clusters in significant concentrations within the whole range of studied composition.

Step-wise kinetics of natural physical ageing in arsenic selenide glasses.

The long-term kinetics of physical ageing at ambient temperature is studied in Se-rich As-Se glasses using the conventional differential scanning calorimetry technique. It is analysed through the changes in the structural relaxation parameters occurring during the glass-to-supercooled liquid transition in the heating mode. Along with the time dependences of the glass transition temperature (T(g)) and partial area (A) under the endothermic relaxation peak, the enthalpy losses (ΔH) and calculated fictive temperature (T(F)) are analysed as key parameters, characterizing the kinetics of physical ageing.

Cooperative rearranging region size and free volume in As-Se glasses.

Glasses of the As-Se system have been used as model objects of the covalent disordered inorganic polymers to investigate the correlation between the cooperative rearranging region (CRR) size determined at the glass transition temperature and the free volume fraction in the glassy state. The CRR size has been determined using temperature modulated differential scanning calorimetry data according to Donth's approach, while the free volume fraction in the investigated materials has been estimated using positron annihilation lifetime spectroscopy data. The obtained results testify that the appearance of open-volume defects greater than 80 Å(3) leads to a significant decrease in the CRR size.

A study of reversible gamma-induced structural transformations in vitreous Ge23.5Sb11.8S64.7 by high-resolution X-ray photoelectron spectroscopy.

The structural origin of reversible gamma-induced effects in vitreous Ge(23.5)Sb(11.8)S(64.