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Aqueous solutions of poly(ethylene glucol) (PEG) of mean molecular mass of 600 g/mol (PEG600) are investigated by Brillouin scattering technique. At high PEG content, a relaxation phenomenon is observed, which is related to a local rearrangement of the polymer structure where the interaction, through hydrogen bonding, with the solvent molecules plays a role.

An investigation is presented of the concentration dependence of the hypersonic properties of solutions of poly(ethylene glycol) of mean molecular mass in benzene and toulene by Brillouin scattering. A high-frequency relaxation process is observed in both the solvents that are assigned to conformational rearrangements of the polymeric chains, trigerred by reorientation of the side group.

Recent phenomenological studies have drawn attention to an appealing effect, observed for the first time in 1893, today known as water-bridge. The phenomenon has been ascribed to unknown properties of water. We report some experimental results showing that, contrary to a widely common belief, the phenomenon is not to be related with water neither with a property of hydrogen bonded networks. Using a very simple model, we show that the liquid bridge phenomenon is originated by electrostatic effects and can be reproduced in any dense fluid with no respect of its peculiar molecular properties. This basic approach is able to reproduce many of the experimentally observed features of the bridge formation. In perspective of future investigations, the possible phenomena responsible of the bridge stability, after its formation, are briefly discussed. [ABSTRACT FROM AUTHOR]

Brillouin scattering experiments have been carried out on some mixtures of molecular liquids. From the measurement of the hypersonic velocities we have evaluated the adiabatic compressibility as a function of the volume fraction. We show how the quadratic form of the excess compressibility dependence on the solute volume fraction can be derived by simple statistical effects and does not imply any interaction among the components of the system other than excluded volume effects. This idea is supported by the comparison of the experimental results with a well-established prototype model, consisting of a binary mixture of hard spheres with a nonadditive interaction potential. This naive model turns out to be able to produce a very wide spectrum of structural and thermodynamic features depending on values of its parameters. An attempt has made to understand what kind of structural information can be gained through the analysis of the volume fraction dependence of the compressibility. [ABSTRACT FROM AUTHOR]

A Brillouin scattering experiment on solutions of poly(ethylene glycol) of mean molecular mass 600 g/mol in CCl4 was described. The relaxation process detected was assigned to conformational rearrangements of the polymeric chains, triggered by reorientation of the side groups.

Purpose: Graves' disease (GD) and Graves' orbitopathy (GO) are multifactorial disorders with links to the gut microbiome and autoimmunity. It is observed that patients with GD exhibit altered gut microbiome diversity. However, little is known about the role of oral microbiota in GD and GO. This study aims to investigate the impact of oral health and oral sanitation on the clinical course of GO in patients disqualified from glucocorticoid treatment due to oral infections., Methods: We reviewed 188 admissions of 127 patients with GO, hospitalized in a tertiary university hospital. Clinical, biochemical, imaging, ophthalmological, and oral health assessment data from each admission were analyzed. Patients excluded from the glucocorticoids (GCs) therapy due to oral foci of infection had the clinical activity score (CAS) reassessed after three months, and they were divided into two groups: with and without improvement., Results: Finishing dental treatment in the meantime was the only factor significantly correlated with improvement in these patients (p = 0.041). The secondary finding was that anti-thyroid peroxidase antibodies titer was significantly higher in the group with oral foci of infection considered as a contraindication for GCs (medians 28.50 vs 128.00; p = 0.026), and those patients were more likely to smoke than the group without oral issues (p = 0.024)., Conclusions: The results of our study suggest that monitoring and treating oral diseases may be pertinent in patients with GO and might serve as a supportive treatment strategy for managing the condition., Key Messages: What is known: There is a recognized link between gut dysbiosis and the autoimmune processes in Graves' Disease (GD) and Graves' Orbitopathy (GO)., What Is New: Elevated levels of TPOAb have been observed in patients with GO who also have oral foci of infection. Dental treatment has been shown to lead to significant clinical improvements in patients with GO. Maintaining oral hygiene might serve as a supportive treatment strategy for managing GO., Competing Interests: Declarations. Ethics approval: We adhered to the ethical standards of the Declaration of Helsinki when we collected, analyzed and reported the data. Due to the retrospective design, the bioethics committee approval is not required. Conflict of interest: The authors declare no conflict of interest., (© 2025. The Author(s).)

The initial and final stages of the isothermal curing reaction between diglycidyl ether of bisphenol A and ethylenediamine were investigated by using Brillouin light scattering spectroscopy. High-frequency acoustic parameters were measured for these stages as a function of the diamine molar fraction, ranging from the pure prepolymer to the pure cross-linker. Significant differences in the concentration dependencies of the mechanical parameters are interpreted in relation to changes in the system's viscoelastic properties. At the final stage of the reaction, the concentration dependencies exhibit notable changes at two characteristic nonstoichiometric compositions─one corresponding to amine excess and the other to epoxy excess. While these concentrations align well with Flory's critical gel points, experimental evidence suggests they should instead be interpreted as vitrification points.

Revision total hip arthroplasty using custom monoflange acetabular components (CMACs) in cases of severe bone loss is becoming an increasingly preferred alternative to traditional implants, which may not provide stable fixation in such cases. However, this procedure also carries a higher risk of infection and implant loosening. This case report discusses a 67-year-old female patient who presented with old acetabular component loosening and significant pelvic bone loss. A 3D model of the pelvis was created based on computed tomography, enabling the design of a personalized monoflange acetabular component. The revision surgery was performed using a posterolateral approach, and the implant was successfully secured. After six months, the patient reported no complications or pain. It seems that CMACs offer a promising alternative for patients presenting with chronic implant loosening and severe bone stock loss., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Bałoniak et al.)

The contraction of nanomaterials triggered by stimuli can be harnessed for micro- and nanoscale energy harvesting, sensing, and artificial muscles toward manipulation and directional motion. The search for these materials is dictated by optimizing several factors, such as stimulus type, conversion efficiency, kinetics and dynamics, mechanical strength, compatibility with other materials, production cost and environmental impact. Here, we report the results of studies on bio-inspired nanomembranes made of poly-catecholamines such as polydopamine, polynorepinephrine, and polydextrodopa. Our findings reveal robust mechanical features and remarkable multi-responsive properties of these materials. In particular, their immediate contraction can be triggered globally by atmospheric moisture reduction and temperature rise and locally by laser or white light irradiation. For each scenario, the process is fully reversible, i.e. , membranes spontaneously expand upon removing the stimulus. Our results unveil the universal multi-responsive nature of the considered polycatecholamine membranes, albeit with distinct differences in their mechanical features and response times to light stimulus. We attribute the light-triggered contraction to photothermal heating, leading to water desorption and subsequent contraction of the membranes. The combination of multi-responsiveness, mechanical robustness, remote control via light, low-cost and large-scale fabrication, biocompatibility, and low-environment impact makes polycatecholamine materials promising candidates for advancing technologies.

Multi-responsive nanomembranes are a new class of advanced materials that can be harnessed in complex architectures for micro and nano-manipulators, artificial muscles, energy harvesting, soft robotics, and sensors. The design and fabrication of responsive membranes must meet such challenges as trade-offs between responsiveness and mechanical durability, volumetric low-cost production ensuring low environmental impact, and compatibility with standard technologies or biological systems This work demonstrates the fabrication of multi-responsive, mechanically robust poly(1,3-diaminopropane) (pDAP) nanomembranes and their application in fast photoactuators. The pDAP films are developed using a plasma-assisted polymerization technique that offers large-scale production and versatility of potential industrial relevance. The pDAP layers exhibit high elasticity with the Young's modulus of ≈7 GPa and remarkable mechanical durability across 20-80 °C temperatures. Notably, pDAP membranes reveal immediate and reversible contraction triggered by light, rising temperature, or reducing relative humidity underpinned by a reversible water sorption mechanism. These features enable the fabrication of photoactuators composed of pDAP-coated Si nanocantilevers, demonstrating ms timescale response to light, tens of µm deflections, and robust performance up to kHz frequencies. These results advance fundamental research on multi-responsive nanomembranes and hold the potential to boost versatile applications in light-to-motion conversion and sensing toward the industrial level., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Background: Graves' orbitopathy (GO) is an autoimmune disorder of the orbit and retro-ocular tissues and the primary extrathyroidal manifestation of Graves' disease. In moderate-to-severe and active GO iv glucocorticoids (GCs) are recommended as first-line treatment. The aim was to assess the safety profile of methylprednisolone administered intravenously for three consecutive days at 1 g in patients with active, moderate-to-severe or sight-threatening Graves' orbitopathy., Methods: We retrospectively evaluated 161 medical records of patients with GO treated with high-dose systemic GCs in the Department of Endocrinology, Metabolic Disorders, and Internal Medicine in Poznań between 2014 and 2021. Clinical data included age, gender, laboratory results, activity and severity of GO, smoking status, disease duration, and presented side effects., Results: The presence of mild side effects was observed during 114 (71%) hospitalizations. The most common complications were hyperglycemia (n = 95) and elevated aminotransferases (n = 31). Increased levels of aminotransferases were more likely observed in smokers and GO duration above 12 months. Based on the multivariate logistic regression, higher TRAb and CAS values were significantly associated with lower odds of hyperglycemia. In turn, the increased odds of elevated aminotransferases were significantly correlated with higher initial ALT levels, female gender, and GO duration above 12 months. In addition, the multidimensional correspondence analysis (MPA) showed that GO patients who declared smoking and had not L-ornithine L-aspartate applied demonstrated a higher probability of elevated aminotransferases., Conclusions: Active GO treatment with high-dose systemic GCs is not associated with serious side effects. Hyperglycemia is the most common steroid-induced complication., (© 2024. The Author(s).)

Aggregation of the polydopamine (PDA) molecular building blocks at the air/water interface leads to obtaining large surface nanometric-thin films. This mechanism follows two possible pathways, namely, covalent or non-covalent self-assembly, which result in a different degree of structure order and, consequently, different structural properties. Control of this mechanism could be vital for applications that require true self-support PDA free-standing films, for example, electrochemical sensing or membrane technology. Here, we are considering the impact of boric acid (BA) and Cu 2+ ions on the mentioned mechanism exclusively for the free-standing films from the air/water interface. We have employed and refined our own spectroscopic reflectometry method to achieve an exceptionally high real-time control over the thickness growth. It turned out that BA and Cu 2+ ions significantly impact the film growth process. Reduction of the nanoparticles size and their number was examined via UV-vis spectroscopy and transmission electron microscopy, showing a colossal reduction in the mean diameter of nanoparticles in the case of BA and a moderate reduction in the case of Cu 2+ . This modification is leading to significant enhancement of the process efficiency through moderation of the topological properties of the films, as revealed by atomic force microscopy. Next, applying infrared, Raman, and X-ray photoelectron spectroscopy, we presented small amounts of metal (B or Cu) in the final structure of PDA and simultaneously their vital role in the oxidation mechanism and cross-linking through covalent or non-covalent bonds. Therefore, we revealed the possibility of synthesizing films via the expected self-assembly mechanism which has hitherto been out of control. Moreover, modification of mechanical properties toward exceptionally elastic films through the BA-assisted synthesis pathway was shown by achieving Young's modulus value up to 24.1 ± 5.6 and 18.3 ± 6.4 GPa, using nanoindentation and Brillouin light scattering, respectively.

Observation of Fano resonances in various physical phenomena is usually ascribed to the coupling of discrete states with background continuum, as it has already been reported for various physical phenomena. Here, we report on Fano lineshapes of nonthermal GHz phonons generated and observed with pumped Brillouin light scattering in gold-silicon thin membranes, overlapping the broad zero-shift background of yet questionable origin. The system's broken mid-plane symmetry enabled the generation of coherent quasi-symmetric and quasi-antisymmetric Lamb acoustic waves/phonons, leading to the four orders-of-magnitude enhancement of Brillouin light scattering. Notably, the membrane asymmetry resulted also in the mode-dependent Stokes and anti-Stokes Fano lineshapes asymmetry., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Bartlomiej Graczykowski reports financial support was provided by National Science Centre Poland. Rafal Bialek reports financial support was provided by National Science Centre Poland. Thomas Vasileiadis reports financial support was provided by National Science Centre Poland., (© 2023 The Authors.)

Hypothesis: Polymer particles self-assembled into colloidal crystals have exciting applications in photonics, phononics, templates for nanolithography, and coatings. Cold soldering utilizing polymer plasticization by supercritical fluids enables a novel, low-cost, low-effort, chemical-free means for uniform mechanical strengthening of fragile polymer colloidal crystals at moderate temperatures. Here, we aim to elucidate the role of particle size and gas-specific response for the most efficient soldering, exploring the full potential of this method., Experiments: We investigate the elastic properties of polystyrene colloidal crystals made of nanoparticles with different diameters (143 to 830 nm) upon treatment with supercritical Ar and He at room temperature. By employing Brillouin light scattering, we quantify the effect of nanoparticle size on the strengthening of interparticle contacts, evaluating the permanent change in the effective elastic modulus upon cold soldering., Findings: The relative change in the effective elastic modulus reveals nonmonotonic dependence on the particle size with the most efficient soldering for mid-sized nanoparticles (about 610 nm diameter). We attribute this behavior to the crucial role of intrinsic fabrication impurities, which reduces the nanoparticles' free surface exposed to plasticization by supercritical fluids. Supercritical Ar, a good solvent for polystyrene, enabled effective soldering of nanoparticles, whereas high-pressure He treatment is entirely reversible., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Meibography is becoming an integral part of dry eye diagnosis. Being objective and repeatable this imaging technique is used to guide treatment decisions and determine the disease status. Especially desirable is the possibility of automatic (or semi-automatic) analysis of a meibomian image for quantification of a particular gland's feature. Recent reports suggest that in addition to the measure of gland atrophy (quantified by the well-established "drop-out area" parameter), the gland's morphological changes may carry equally clinically useful information. Here we demonstrate the novel image analysis method providing detailed information on local deformation of meibomian gland pattern. The developed approach extracts from every Meibomian image a set of six morphometric color-coded maps, each visualizing spatial behavior of different morphometric parameter. A more detailed analysis of those maps was used to perform automatic classification of Meibomian glands images. The method for isolating individual morphometric components from the original meibomian image can be helpful in the diagnostic process. It may help clinicians to see in which part of the eyelid the disturbance is taking place and also to quantify it with a numerical value providing essential insight into Meibomian gland dysfunction pathophysiology., Competing Interests: The authors have declared that no competing interests exist.

The actuation of micro- and nanostructures controlled by external stimuli remains one of the exciting challenges in nanotechnology due to the wealth of fundamental questions and potential applications in energy harvesting, robotics, sensing, biomedicine, and tunable metamaterials. Photoactuation utilizes the conversion of light into motion through reversible chemical and physical processes and enables remote and spatiotemporal control of the actuation. Here, we report a fast light-to-motion conversion in few-nanometer thick bare polydopamine (PDA) membranes stimulated by visible light. Light-induced heating of PDA leads to desorption of water molecules and contraction of membranes in less than 140 μs. Switching off the light leads to a spontaneous expansion in less than 20 ms due to heat dissipation and water adsorption. Our findings demonstrate that pristine PDA membranes are multiresponsive materials that can be harnessed as robust building blocks for soft, micro-, and nanoscale actuators stimulated by light, temperature, and moisture level.

Background: Slipped capital femoral epiphysis (SCFE) is a hip disorder frequently occurring in adolescence. In adults it is rare and so far very few cases have been documented., Case Presentation: This report presents a 25-year-old patient diagnosed with an anterior fossa giant chondroma, hypogonadotropic hypogonadism, and SCFE. The patient underwent surgical and hormonal therapy. His symptoms revealed, and he became a father., Conclusions: Every patient diagnosed with SCFE in adulthood should undergo endocrinological assessment based on physical examination and laboratory tests., (© 2021. The Author(s).)

Colloidal crystals realized by self-assembled polymer nanoparticles have prominent attraction as a platform for various applications from assembling photonic and phononic crystals, acoustic metamaterials to coating applications. However, the fragility of these systems limits their application horizon. In this work the uniform mechanical reinforcement and tunability of 3D polystyrene colloidal crystals by means of cold soldering are reported. This structural strengthening is achieved by high pressure gas (N 2 or Ar) plasticization at temperatures well below the glass transition. Brillouin light scattering is employed to monitor in-situ the mechanical vibrations of the crystal and thereby determine preferential pressure, temperature and time ranges for soldering, i.e. formation of physical bonding among the nanoparticles while maintaining the shape and translational order. This low-cost method is potentially useful for fabrication and tuning of durable devices including applications in photonics, phononics, acoustic metamaterials, optomechanics, surface coatings and nanolithography., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

In recent years, significant progress has been made in the Meibography technique resulting from the use of advanced image analysis methods allowing a quantitative description of the Meibomian gland structures. Many objective measures of gland distortion were previously proposed allowing for user-independent classification of acquired gland images. However, due to the complicated nature of gland deformation, none of the single-valued parameters can fully describe the analyzed gland images. There is a need to increase the number of descriptive factors, selectively sensitive to different gland features. Here we show that global 2D Fourier transform analysis of infra-red gland images provides values of two new such parameters: mean gland frequency and anisotropy in gland periodicity. We show that their values correlate with gland dysfunction and can be used to automatically categorize the images into the three subjective classes (healthy, intermediate and unhealthy). We also demonstrated that classification performance can be improved by dimensionality reduction approach using principal component analysis., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose of Review: Heart failure with preserved ejection fraction (HFpEF) is a relatively new disease entity used in medical terminology; however, both the number of patients and its clinical significance are growing. HFpEF used to be seen as a mild condition; however, the symptoms and quality of life of the patients are comparable to those with reduced ejection fraction. The disease is much more complex than previously thought. In this article, information surrounding the etiology, diagnosis, prognosis, and possible therapeutic options of HFpEF are reviewed and summarized., Recent Findings: It has recently been proposed that heart failure (HF) is rather a heterogeneous syndrome with a spectrum of overlapping and distinct characteristics. HFpEF itself can be distilled into different phenotypes based on the underlying biology. The etiological factors of HFpEF are unclear; however, systemic low-grade inflammation and microvascular damage as a consequence of comorbidities associated with endothelial dysfunction, oxidative stress, myocardial remodeling, and fibrosis are considered to play a crucial role in the pathogenesis of a disease. The H 2 FPEF score and the HFpEF nomogram are recently validated highly sensitive tools employed for risk assessment of subclinical heart failure. Despite numerous studies, there is still no evidence-based pharmacotherapy for HFpEF and the mortality and morbidity associated with HFpEF remain high. A better understanding of the etiological factors, the impact of comorbidities, the phenotypes of the disease, and implementation of machine learning algorithms may play a key role in the development of future therapeutic strategies.

Brillouin microscopy recently attracted much attention for being a promising tool for all-optical label-free determination of mechanical properties of biological samples. Before its widespread utilization for biomedical applications, numbers of nuances related with this technique need to be recognized. In this article, we discuss the process of structural relaxation, the phenomena not commonly addressed by the emerging bio-Brillouin community, and its effect on longitudinal rigidity modulus. Using a model aqueous polymer mixture, we show how scattering measurements performed on the same specimen using different experimental geometries can lead to different results., Competing Interests: The authors declare that there are no conflicts of interest related to this article.