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Layered double hydroxide (LDH) phases that form during cement hydration can incorporate a variety of interlayer anions in their interlayer positions. Here, a range of phases of general formula [MII(1−x)MIII(x)(OH)2][An−]x/n·zH2O were synthesized, where MII = Mg2+ (hydrotalcite) or Ca2+ (AFm), MIII = Al3+ such that [MII/Al] = 2 (Ca and Mg, atomic units) or 3 (Mg only), and A = Cl−, Br−, or I−. All the synthesized phases were characterized to assess their composition, density, and crystal structure. By approach from undersaturation, the solubility data of these compounds was measured at 5, 25, and 60°C. This thermochemical data was used to successfully model their formation using thermodynamic modeling and to infer the fields of stability of these compounds for conditions of relevance to cementitious systems. It is seen that halide-containing hydrotalcite phases strongly compete with hydroxide-containing hydrotalcite, with the latter prevailing at high pH. In contrast, halide-containing AFm compounds are more stable compared with hydroxide-containing AFm compositions.

Quantum sensors find applications ranging from material science to biophysics. Nitrogen‐vacancy (NV) center in diamond has been successfully implemented for measuring various types of signals. Optical NV center readout, routinely used in confocal microscopes, allows achieving high spatial resolution down to the diffraction limit. This work describes in detail the combined confocal‐atomic‐force microscope (confocal‐AFM), which takes advantage of sharp AFM cantilevers, and shows its possible applications for nanoscale resolution. It demonstrates the sub‐diffractional localization of NV centers with platinum‐coated cantilevers and the ability to separately address optically unresolved sensors using cantilevers with ferromagnetic coating. The presented setup exhibits a lateral resolution of 13 nm, providing a tool for nanoscale quantum sensing. [ABSTRACT FROM AUTHOR]

The effects of biodegradable corn peptone on the corrosion behavior of mild steel in 0.1M HCl were evaluated. The results from the weight loss experiments indicate that changing the amount of corn peptone from 50 to 500 ppm considerably decreased the corrosion rate of the coupons from 28.24 to 4.67 mpy. However, heating the solutions had negative effects on this trend. According to the calculations, dissolving the inhibitor modified the thermodynamic parameters of the corrosion phenomenon. In addition, the adsorption of corn peptone was best fitted with the Langmuir isotherm. The Tafel polarization plots revealed that the presence of corn peptone decreased the corrosion current density from 134.9 to 6.7 µA cm−2. This was compatible with the electrochemical impedance spectroscopy data. Furthermore, X‐ray photoelectron spectroscopy analysis confirmed the adsorption of the tested peptone on the surface of the working electrodes, which based on the atomic force microscope images, reduced the surface roughness of the specimens. [ABSTRACT FROM AUTHOR]

[Display omitted] Nanobubbles (NBs) are classified in two distinct categories: surface and bulk. Surface NBs are readily observed using atomic force microscopy (AFM), while the existence of bulk NBs has been a subject of debate, conflicting with the diffusion theory's predictions. Current methodologies for identifying bulk NBs yield inconclusive results. In this study, Langmuir Blodgett (LB) technique and AFM, are utilized to visualize NB imprints on anionic, cationic and zwitterionic lipid films deposited on glass-slide substrates. Our analysis of Langmuir monolayers compression isotherms reveals the impact of bulk NBs on lipid monolayer development. AFM scans of the deposited lipid films consistently show NB imprints. Notably, cationic and zwitterionic film depositions exhibit NB formations from the 1st layer, whereas in anionic films, these formations are observed only after the 3rd layer. These results suggest that the origin of these imprinted formations may be attributed to bulk NBs. [ABSTRACT FROM AUTHOR]

In this article, we report undoped SnO2 and PbO-doped SnO2 thick films to study their microstructural and sensing behaviours. Three samples have been fabricated using a screen-printing technique on an alumina substrate and these are S1 (undoped SnO2), S2 (1 wt% PbO-doped SnO2 firing at 800°C) and S3 (1 wt% PbO-doped SnO2 firing at 900°C). XRD and AFM techniques are used to observe the microstructural behaviours and it is found that the crystallite size decreases with PbO doping. The sensing properties, such as sensing response, selectivity and transient time of the deposited thick films, were studied at an operating temperature of 200°C for various test gases such as ethanol, LPG and acetone concentrations (0–5000 ppm level). Also, we found that the response of sensor S3 to the ethanol gas is ~3.38 times of LPG and ~1.95 times that of acetone gas. The response and recovery times of the ethanol gas for the S3 sensor are 41 and 125 s, respectively. Therefore, the PbO doping improves the response and recovery time for ethanol gas (5000 ppm) over LPG and acetone. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the surface roughness (SR) and color changes of single‐shade and nanohybrid resin‐based restorative materials (RBC) after immersion in liquids at different pH values. For RBCs, a total of 120 specimens, 30 for each material, were prepared using 10 mm diameter and 2 mm thick molds. For flowable bulk fill RBC, a total of 40 specimens, 10 for each material, were prepared using 10 mm diameter and 4 mm thick molds (n = 10). After initial color and SR measurements, samples were stored in the liquids for 14 days and all of the measurements were repeated on 14th days. Scanning electron microscopy and atomic force microscopy analyzes were performed in all groups. When SR results are examined; among all liquids, the highest SR value was observed in the Carisma Diamond One (CDO) group, while the lowest SR value was observed in the Omnichroma Flow Bulk (OMF) group (p <.05). When the color changes (ΔE) results are examined; it was observed that CDO group had highest color change and OMF group had the lowest values. It has been observed that among the liquids, the liquids that affect the ΔE values of the materials the most are coffee and cola. When the ΔE values of the subgroups of the materials were examined, there was a statistically significant difference in all subgroups of RBCs (p <.05). While acidic liquids increased the SR of RBCs, coffee more affected the color change of RBCs. Research Highlights: Clinicians should keep in mind that the RBCs tested may change their surface properties and colors when exposed to various liquids. People who have RBCs should pay attention to the consumption of acidic and highly pigmented liquids. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The European Union’s efforts to increase the share of renewable energy translate into a growing number of wind farms. Post-operation wind turbines become increasing waste. Recycling wind turbine blades is a challenge due to the materials used (composites) and high costs. The article examines the influence of recyclate from wind turbine blades (derived from mechanical recycling) on the image of topography and Lateral Force Microscopy (LFM) in atomic force microscopy (AFM). Upon adding the recycled material, an increase in surface roughness is observed despite its prior polishing. The Young’s modulus determined from force spectroscopy (AFM mode) indicated a small difference in values between the matrix and reinforcement areas. This proves the significant influence of the primary and secondary interphase on the properties of secondary composites, which is an area for further research. [ABSTRACT FROM AUTHOR]

The characterization and evolution of corrosion products deposited on/around MnSs, a typical kind of inclusive particle embedded in AISI 304 stainless steel, was analyzed using a quasi-in-situ method in a 3.5 wt.% NaCl solution. On/around the MnS inclusion, a corrosion product layer with spinel Fe3−xCrxO4 as the main component was formed, with a thickness of several hundred nanometers. Below the layer, there was a cavity layer in which part of the MnS remained, forming secondary pitting along the MnS/matrix boundary. The mechanism of corrosion product deposition and evolution accompanied by MnS dissolution, as well as the characteristics of the corrosion products, are discussed. [ABSTRACT FROM AUTHOR]

Natural fibers derived from plants were gaining favor as a viable alternative to synthetic materials. However, searching for sustainable raw materials with superior qualities is cumbersome because most natural fibers are limited to specific geographical areas. Himalayacalamus falconeri (HF) is a fast-growing plant that is abundant in the hills of Uttarakhand, India. This study is aimed at extracting fibers from the stem of Himalayacalamus falconeri (HF) culms, and investigate their properties by XRD analysis, TGA analysis, AFM analysis, and single-fiber tensile test. The extracted HF fiber was alkali-treated to enhance its mechanical properties. It was observed that the alkali treatment on HF fibers increased the cellulose content by 6%, and density by 4% compared with untreated fiber. Furthermore, the removal of amorphous components from the fiber surface resulted in a decrease in diameter from 103.95 to 94.4 μm. In addition, the alkali treatment on HF fiber enhanced the material's crystallinity index (from 58.92 to 67.79%), tensile strength (from 132 to 196.5 MPa), thermal stability (from 250 to 258 °C), and surface roughness (from 23.478 to 37 nm). The experimental findings confirmed that HF fiber is a suitable replacement material for synthetic reinforcement materials in lightweight polymer composites. [ABSTRACT FROM AUTHOR]

Different dyes are discharged into water streams, causing significant pollution to the entire ecosystem. The present work deals with the removal of acid red 2 dye (methyl red—as an anionic dye) by green sorbents based on chitosan derivatization. In this regard, two classes of chitosan derivatives—a total of six—were prepared by gamma irradiation at 30 kGy. The first group (group A) constitutes a crosslinked chitosan/polyacrylamide/aluminum oxide with different feed ratios, while the second group, identified as group B, is composed of crosslinked carboxymethyl chitosan/polyacrylamide/aluminum oxide with different ratios. Glycerol was added to soften the resultant hydrogels. The products were characterized by different tools, including FTIR for confirming the chemical modification, TGA for investigating their thermal properties, and XRD for verifying their crystalline structure. The morphology of the prepared derivatives was studied through SEM, while their topography before and after dye adsorption was monitored via the AFM. The removal efficiencies of the prepared sorbents were verified at different operation conditions, such as pH, temperature, adsorbent dose, initial concentration of dye solutions, and contact time. The data revealed that the optimum conditions for maximum dye uptake were as follows: pH 4, contact time 120 min, 0.1-g sorbent dose, and 50-ppm dye concentration. Additionally, the prepared sorbents demonstrated potent adsorption capacity and removal efficiency. It was found that the elements of the second group displayed higher performance than their counterparts. The data showed also that the adsorption process best fits with the Freundlich model and obeyed pseudo-first-order kinetic isotherm. In addition, the synthesized composites showed observable antibacterial potency toward E. coli as a Gram-negative bacterium and S. aureus as a Gram-positive bacterium. [ABSTRACT FROM AUTHOR]

In this paper, a new pyrazole derivative, namely, (2-(((3,5-dimethyl-1H-pyrazol-1-yl)methyl)amino)-5-nitrophenyl)(phenyl) methanone (2-DPM) was uniquely used as an inhibitor of corrosion for carbon steel (C-S) in acidic solution (1 M HCl). Numerous techniques include electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), surface morphology analysis (SEM), energy-dispersive X-ray spectrometry (EDX), atom force microscopy (AFM), angle of contact, X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), and UV-visible analysis. Molecular dynamic simulations (MDs) and quantum chemical computations (DFT) were utilized to assess the 2-DPM ability. The results show that the inhibitor, acting in a mixed inhibitory mode, considerably reduces the incidence of C-S corrosion by protecting the metal surface with an effective protective layer. The chemically adsorbed novel pyrazole (2-DPM) molecule has an improved corrosion performance of nearly 96% at 303 K, which is supported by EIS and theoretical analyses. The Langmuir isotherm model was shown to regulate the adsorption of 2-DPM on the surface of C-S. Finally, there is a strong correlation between theoretical research and experimental findings. [ABSTRACT FROM AUTHOR]

Membrane surface fouling has always been a critical issue for the long-term operation of polymeric membranes. Therefore, it is crucial to develop new approaches to prevent fouling. While developing new approaches, characterization methods are greatly important for understanding the distribution of fouling on the membrane surface. In this work, a cellulose acetate membrane was fouled by the filtration of artificial wastewater based on alginate. The surfaces of fouled membranes were characterized through scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), atomic force microscopy (AFM), and white light interferometry (WLI). The results were then compared in terms of the resolution, accuracy, feasibility, and cost-efficiency. [ABSTRACT FROM AUTHOR]

Thermoset resins are singular materials in the field of microelectronics. Because they exhibit a high contrast of thermomechanical properties with other integrated materials like oxides, metals or silicon, polymers can threaten the mechanical integrity of stacks. Knowing polymer properties allows manufacturers to foresee the compatibility between materials and improve chipsets reliability. At a bilayer scale, the properties mismatch between the polymer film and the silicon substrate causes an overall curvature of the wafer which evolves with temperature. By comparing the thermally induced curvature of two distinct substrates with the same film, the biaxial modulus and the coefficient of thermal expansion of the film can be determined. This method can not only check the achievement of the polymer cross-linking, but also estimates their relaxation temperatures. In this article, we present the ability of this method to, not only, measure those properties in the glassy state, but also, for the first time, in the rubbery state. We also illustrate the proficiency of this approach in detecting and characterizing two successive glassy states. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: Naturally extracted polysaccharides, such as guar gum, are promising candidates for environmentally friendly flotation reagents. It is hypothesized that the kinetics of collision of sub- to millimeter gas bubbles with a hydrophobic graphite surface, and the stability of thin liquid film formed between the bubble and surface is affected by an adsorbed layer of guar gum. Experiments: A combination of gravimetric (quartz crystal microbalance with dissipation) and imaging (atomic force microscopy) techniques was used to investigate the adsorption of guar gum on graphite surface, while high-speed camera imaging allowed for direct observation of the bubble collision process with guar gum-modified graphite surfaces with millisecond resolution. Findings: Atomic force microscope topography images revealed a guar gum concentration-dependent interconnected network of guar gum molecules adsorbed at graphite surface. These adsorbed molecules at low surface coverage, changed the wettability of the graphite surface, resulting in a film drainage time longer by an order of magnitude, while at higher surface coverage successfully prevented bubble attachment to the graphite surface. Most importantly, the adsorbed layer changed the strength of the bubble's bouncing off the graphite surface. This enhanced bubble bouncing can be correlated with the film drainage time and used to predict a successful bubble-particle attachment. [ABSTRACT FROM AUTHOR]

The topological and morphological changes of the (001) surface of single‐crystal (La0.3Sr0.7)(Al0.65Ta0.35)O3 during treatment with high‐purity deionized water (DI) have been investigated by atomic force microscopy and scanning transmission electron microscopy (STEM). Etching by DI treatment at room temperature proceeded mainly in anisotropic etching mode, resulting in rectangular etch pits with {001} inner surfaces forming in the surface. The dominant etching mode changed from anisotropic to isotropic with increasing DI‐treatment temperature, and the lowest surface roughness occurred for DI treatment at 50°C for 60 min. Direct observation of the atomic structure of the surface by STEM showed that the etched surface was the B‐site‐terminated (001) surface after anisotropic etching at 50°C for 60 min, in which the B‐site‐terminated atomic layer was found to maintain the B‐site ordered structure existing in the crystal. This is because DI treatment, which does not require high‐temperature heat treatment of the substrate, suppresses element diffusion, sublimation, and formation of point defects on and in the vicinity of the surface. [ABSTRACT FROM AUTHOR]

In this study, substrates of glass were used for the deposition of transparent nanostructured thin layers of Titanium dioxide (TiO2) using a spin-coating system, and the solution was processed by sol-gel process. TiO2 sol and films were prepared with TTIP, hydrochloric acid, DI water, and ethanol. Here is the current work, these thin films were analyzed for various annealing treatments at 300°C, 400°C, 500°C. The various attributes of films such as structural are described by X-ray diffraction (XRD) and RAMAN spectroscopy, morphology, and topography are studied by SEM and AFM, and optical properties are examined by UV-Vis spectroscopy. The direct energy bandgap estimated for the TiO2 films is 3.65ev, 3.71ev, and 3.75ev after heating at 300°C-400°C-500°C. The initial crystalline phase (anatase) of TiO2 shows up after 400°C for the four layers which are confirmed by XRD and RAMAN studies. At high temperatures, brookite and rutile crystalline phases are also found with the anatase phase. The attained films are translucent in the wavelength range between 380-700nm and blurred in the 100-380nm range. [ABSTRACT FROM AUTHOR]

In this study, aluminum-based metal matrix composites (MMCs) were fabricated with varying compositions of SiC and TiO2 reinforcements using the stir casting method. Three different compositions were examined: 98% Al6061 alloy, 1% SiC, and 1% TiO2; 96% Al 6061 alloy, 2% SiC, and 2% TiO2; and 94% Al alloy, 3% SiC, and 3% TiO2. These MMCs were evaluated for their mechanical behavior and microstructure in terms of tensile, flexural, and impact strength. Scanning electron microscopy (SEM) analysis revealed a uniform distribution of reinforcements, while also indicating an uneven dispersion of SiC particles within the Al matrix. Tensile testing displayed an ultimate strength of 160.06 MPa, an elongation of 6.63%, and a hardness of 96.5 for the sample with the composition of 94% Al, 3% SiC, and 3% TiO2. For the composition of 96% Al alloy, 2% SiC, and 2% TiO2, the highest flexural strength of 6.57 kN, notable impact strength of 6 J, and a hardness value of 93.68 were achieved. Atomic force microscopy (AFM) was employed to analyze surface morphology. These results demonstrate the potential of these MMCs for practical applications due to their improved properties compared to commercially available composites. The study highlights the tailored mechanical attributes of metal matrix composites, showcasing their strength, stiffness, fatigue resistance, and corrosion resistance. Such systematic analyses aid in the development of more efficient and dependable structures for wind turbine applications. [ABSTRACT FROM AUTHOR]

As the first boundary between the environment and the material, the surface plays an important role in their interaction with each other, therefore, the use of appropriate tools and analysis to examine the mechanical properties and morphology of surfaces has particular importance in industry and research. In this research, a thin film of nickel was deposited on metal substrates made of aluminum, copper, and steel by using the RF magnetic cathode. Then, using a non‐contact atomic force microscope, the morphological properties of the nickel film with static parameters, Minkowski functionals (MF's), fractal, and multifractal were extracted to be analyzed and studied. After that, using parameters such as root mean square (RMS) roughness, skewness, and kurtosis, it was determined how the surface roughness, distribution, and probability density of particles on the film surface alters with the change of the substrate. Next, by examining and analyzing the Δα and Δf parameters obtained from the multifractal section, the morphology of the produced film on the metal substrates was investigated. Then, the change in the surface plasmon resonance (SPR) peak position is changed for the prepared film in the range of the absorption spectrum due to the substrate effect and the microstructural properties of the formed film. Highlights: Ni film has been deposited by Rf magnetron sputtering.The effect of metal substrates on the topography, fractality, and optical properties was studied.Minkowski functionals were used to investigate the surface morphology of the samples.Substrate's material and the topography of the formed film can changed the surface plasmon resonance position. [ABSTRACT FROM AUTHOR]

The magnitude of vascular residual stress, an inherent characteristic exclusive to the vasculature, exhibits a strong correlation with vascular compliance, tensile resistance, vascular rigidity, and vascular remodeling subsequent to vascular transplantation. Vascular residual stress can be quantified by evaluating the magnitude of the opening angle within the vascular ring. For decellularized vessels, the vascular ring's opening angle diminishes, consequently reducing residual stress. The decellularization process induces a laxity in the vascular fiber structure within decellularized vessels. To investigate the interrelation between the magnitude of residual stress and the microstructure as well as mechanical properties of elastin and collagen within blood vessels, this study employed fresh blood vessels, stress‐relieved vessels, and sections of decellularized blood vessels. Structural scanning and force map experiments on the surface of the sections were conducted using atomic force microscopy (AFM). The findings revealed well‐organized arrangements of elastin and collagen within fresh vessels, wherein the regularity of collagen and elastin exhibited variability as residual stress declined. Furthermore, both stress‐relieved and decellularized vessel sections exhibited a reduction in the mean Young's modulus to varying extents in comparison to fresh vessels. The validity of our experimental results was further corroborated through finite element simulations. Hence, residual stress assumes a crucial role in upholding the structural stability of blood vessels, and the intricate association between residual stress and the microstructural and micromechanical properties of blood vessels holds significant implications for comprehending the impact of vascular diseases on vascular structure and advancing the development of biomimetic artificial blood vessels that replicate residual stress. Research Highlights: In this inquiry, we scrutinized the interconnection amid vascular residual stress and the microscale and nanoscale aspects of vascular structure and mechanical function, employing AFM. We ascertained that residual stress assumes a pivotal role in upholding vascular microstructure and mechanical attributes. The experimental outcomes were subsequently validated through finite element simulation. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrogels are usually depicted as a homogenous polymer block with a distinct surface. While defects in the polymer structure are looked into frequently, structural irregularities on the hydrogel surface are often neglected. In this work, thin hydrogel layers of ≈100 nm thickness (nanogels) are synthesized and characterized for their structural irregularities, as they represent the surface of macrogels. The nanogels contain a main‐chain responsiveness (thermo responsive) and a responsiveness in the cross‐linking points (redox responsive). By combining data from ellipsometry using box‐model and two‐segment‐model analysis, as well as atomic force microscopy, a more defined model of the nanogel surface can be developed. Starting with a more densely cross‐linked network at the silica wafer surface, the density of cross‐linking gradually decreases toward the hydrogel–solvent interface. Thermo‐responsive behavior of the main chain affects the entire network equally as all chain segments change solubility. Cross‐linker‐based redox‐responsiveness, on the other hand, is only governed by the inner, more cross‐linked layers of the network. Such dual responsive nanogels hence allow for developing a more detailed model of a hydrogel surface from free radical polymerization. It provides a better understanding of structural defects in hydrogels and how they are affected by responsive functionalities. [ABSTRACT FROM AUTHOR]

In this investigation, atomic force microscopy (AFM) was employed to meticulously examine the electromigration phenomena occurring in pure gold nanowires possessing a mere 10 nm thickness. The study elucidates the dynamic evolution of the micromorphology of gold nanowires during the electromigration process, providing insights into the intricate processes leading to the formation of voids, hillocks, and nano gaps. Significantly, the intricate relationship between these morphological changes and the consequential impact on electrical properties, particularly the resistance of the nanowires, is systematically unveiled. A qualitative analysis of the formation mechanisms behind voids and hillocks was conducted, contributing to a deeper understanding of the electromigration-induced phenomena. This study holds significance in controlling the width and position of metal nanogaps, offering promising avenues for the advancement of gap-based nanoelectronic and memory devices. [ABSTRACT FROM AUTHOR]

Polyamide-6 (PA6), or nylon-6, is a widely used low-cost polymer material for various applications. Manufacturing PA6 into fibers involves a spinning process which orients the polymer chains into a semicrystalline structure. The most economical spinning process for PA6 fibers is melt extrusion. When stretching the produced fibers to high strains, the PA6 fibers transition the metastable γ phase back into the stable α phase. The effects of these large stretches on mechanical properties have not been explored after the stretch has been released. In this study, the effects on mechanical properties were studied by stretching the PA6 fibers from 10 to 50% tensile strain and subsequently releasing the fibers. The stretched fibers were characterized by X-ray diffraction and atomic force microscopy to determine the changes to the crystal structure and surface roughness. The stretched fibers were then tensile tested to failure and the tensile properties were examined. The stress-strain curves on the post-stretched PA6 fibers showed clear softening in the fibers with lower initial moduli after 30% stretching. These results may hold a clue to softening of fibers in applications with repeated loading and have implications for mechanical stability and fatigue of this polymeric material. [ABSTRACT FROM AUTHOR]

Neurodegenerative disorders cause most physical and mental disabilities, and therefore require effective treatment. The blood–brain barrier (BBB) prevents drug molecules from crossing from the blood to the brain, making brain drug delivery difficult. Implantable devices could provide sustained and regulated medication to solve this problem. Two electrolytes (0.3 M oxalic acid and 0.3 M sulphuric acid) were used to anodise Al2O3 nanoporous membranes, followed by a third anodisation in concentrated H2SO4 to separate the through-hole membranes from the aluminium substrate. FTIR, AFM, and SEM/EDX were used to characterise the membranes' structure and morphology. The effects of the anodisation time and electrolyte type on the AAO layer pore density, diameter, interpore distance, and thickness were examined. As a model drug for neurodegenerative disorders, donepezil hydrochloride (DHC) was loaded onto thin alumina nanoporous membranes. The DHC release profiles were characterised at two concentrations using a UV–Vis spectrophotometer. Oxalic acid membranes demonstrated an average pore diameter of 39.6–32.5 nm, which was two times larger than sulphuric acid membranes (22.6–19.7 nm). After increasing the anodisation time from 3 to 5 h, all of the membranes showed a reduction in pore diameter that was stable regardless of the electrolyte type or period. Drug release from oxalic acid-fabricated membranes was controlled and sustained for over 2 weeks. Thus, nanoporous membranes as implantable drug delivery systems could improve neurodegenerative disease treatment. [ABSTRACT FROM AUTHOR]

Background: Function of thyroid gland is regulated by the axis hypothalamic- pituitarythyroid through these hormones: Thyrotrophin releasing hormone (TRH), thyroid stimulating hormone (TSH), tetraiodothyronine hormone (T4) and triiodothyronine hormone (T3). Thyroid disorders(hyperthyroidism or hypothyroidism) are common around the world and are common diseases in Iraq. Thyroid disorders are states that initially affect on amount of hormones that produced by the thyroid, and affects on all physiological systems including central nervous system, cardiovascular system, blood, and others. Afamin (AFM) is an 87 Kilodalton (kDa) glycoprotein that shares 55% of the amino acid sequence of albumin and contains 15% of carbohydrates. Vimentin (VIM) is a protein among 70 types of intermediate filaments, including Vimentin, Keratin, Desmin and Lamin. Vimentin is a cytoskeleton is an intermediate filament protein that makes up the nucleus and muscle cells. Aimes of study: We aimed to evaluate levels of Afamin, Vimentin and number of biochemical variables (TRH,TSH,T3 and T4) with Body mass index (BMI) in females patients with thyroid disorders. Methods: The study groups include 30 women with hyperthyroidism, 30 women with hypothyroidism and a control group of 30 healthy women with ages between(18-45) years, From September 2023 until March 2024. Protein assays include Afamin, Vimentin levels and number of biochemical variables( TRH,TSH,T3 and T4) in females patients with thyroid disorders . Results: The results of current study showed a significant increase at (P≤ 0.05) in AFM (227.67 ± 32.31), VIM(40.00 ± 4.39) levels with TRH(225.04± 57.08), TSH (11.71 ± 2.77) and BMI (29.70 ± 2.86) in patients with hypothyroidism group compared to (hyperthyroidism and healthy) groups. Levels of T3 (0.76 ± 0.14) and T4 (3.33 ± 0.79) showed a significant decrease at (P≤0.05) in hypothyroidism group compared to hyperthyroidism and healthy groups, While TSH (0.25 ± 0.08) levels showed a significant decrease at (P≤ 0.05) in hyperthyroidism group compared to hypothyroidism group and healthy group. Concentrations of T4 (13.42 ± 1.36) with T3 (2.16 ± 0.42) showed a significant increase at (P≤ 0.05) in hyperthyroidism group compared to hypothyroidism and healthy groups. Conclusions: We conclude from results of current study that high levels of AFM and VIM are associated with high levels of TRH,TSH and BMI in hypothyroidism group . Serum levels of AFM and VIM may be a new biomarkers for detecting and monitoring thyroid disorders, and may be an important useful clinical tools for detecting and monitoring thyroid disturbances. [ABSTRACT FROM AUTHOR]

Thin films of zinc sulfide (ZnS) with varying thicknesses have been successfully fabricated using radio frequency magnetron sputtering on glass substrates at a temperature of 300 K. Structural analysis via X-ray diffraction and selected area electron diffraction confirmed the presence of nanocrystalline cubic ZnS phases in the films. The crystallite size, determined from X-ray diffraction lines, ranged between 42 and 55 nm. We also explored the morphological attributes of these surfaces and observed significant changes in both grain shape and size. Our atomic force microscopy analyses revealed that the thinner film displayed a topography marked by thinner, elongated rough peaks. As the film thickness increased, these rough peaks gradually transformed into wider, flatter features. Additionally, the films exhibited distinct percolation properties, which were undeniably tied to the alterations in the shape and size of the ZnS grains on their surfaces. Thinner samples demonstrated more pronounced surface percolation (FS > 0.5) compared to thicker samples, which displayed reduced surface percolation. Furthermore, we noted that the 250 nm film predominantly showcased strongly multifractal 3D spatial patterns in contrast to the other films. Spectroscopic measurements in the UV–visible-near infrared region revealed high transparency across the 350–850 nm spectra, with a noticeable blue shift in the absorption edge. Calculations yielded direct allowed band gaps within the range of 3.69–3.85 eV. These results indicate that the optical properties of films can be tailored by their structural and morphological characteristics, thereby offering valuable guidance for their appropriate applications. [ABSTRACT FROM AUTHOR]

Enterovirus D68 (EV-D68) is an emerging pathogen that can cause severe respiratory and neurologic disease [acute flaccid myelitis (AFM)]. Intramuscular (IM) injection of neonatal Swiss Webster (SW) mice with US/IL/14-18952 (IL52), a clinical isolate from the 2014 EV-D68 epidemic, results in many of the pathogenic features of human AFM, including viral infection of the spinal cord, death of motor neurons, and resultant progressive paralysis. In distinction, CA/14-4231 (CA4231), another clinical isolate from the 2014 EV-D68 outbreak, does not cause paralysis in mice, does not grow in the spinal cord, and does not cause motor neuron loss following IM injection. A panel of chimeric viruses containing sequences from IL52 and CA4231 was used to demonstrate that VP1 is the main determinant of EV-D68 neurovirulence following IM injection of neonatal SW mice. VP1 contains four amino acid differences between IL52 and CA4231. Mutations resulting in substituting these four amino acids (CA4231 residues into the IL52 polyprotein) completely abolished neurovirulence. Conversely, mutations resulting in substituting VP1 IL52 amino acid residues into the CA4231 polyprotein created a virus that induced paralysis to the same degree as IL52. Neurovirulence following infection of neonatal SW mice with parental and chimeric viruses was associated with viral growth in the spinal cord. IMPORTANCE Emerging viruses allow us to investigate mutations leading to increased disease severity. Enterovirus D68 (EV-D68), once the cause of rare cases of respiratory illness, recently acquired the ability to cause severe respiratory and neurologic disease. Chimeric viruses were used to demonstrate that viral structural protein VP1 determines growth in the spinal cord, motor neuron loss, and paralysis following intramuscular (IM) injection of neonatal Swiss Webster (SW) mice with EV-D68. These results have relevance for predicting the clinical outcome of future EV-D68 epidemics as well as targeting retrograde transport as a potential strategy for treating virus-induced neurologic disease. [ABSTRACT FROM AUTHOR]

We introduce a novel rotational stage based on inertial motion, designed to be lightweight, compact, and fully compatible with atomic force microscopy (AFM) systems. Our characterization of this stage demonstrates high angular precision, achieving a maximum rotational speed of 0.083 rad/s and a minimum angular step of 11.8 μrad. The stage exhibits reliable performance, maintaining continuous operation for extended periods. When tested within an AFM setup, the stage deliveres excellent results, confirming its efficacy for scanning probe microscopy studies. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of rotation frequency (rpm) of different polishing discs on the surface roughness of a nanohybrid resin composite material. 126 specimens were prepared in metal molds of 10 mm diameter and 2 mm depth using a nanohybrid resin composite material. The prepared specimens were kept in distilled water for 24 hours. Polishing treatments at 5k, 10k, 15k, and 20k rpm were applied to the nanohybrid resin composite material by grouping different brand polishing discs: Sof-Lex Contouring and Polishing Discs (3M Espe, USA) (3M Group), Optidisc (Kerr Corporation, USA) (Kerr Group), Super-Snap Rainbow Technique Kit (Shofu Dental, Japan) (Shofu Group), Finishing Disc (Bisco Dental, USA) (Bisco Group). The surface roughness was evaluated at three different points by atomic force microscopy for all specimens and scanning electron microscopy was used for visual assessment. Data were evaluated by Two Way ANOVA and Tukey's HSD Test. The mean surface roughness (Ra, μm) of all prepared samples showed significant differences (α = 0.05). According to Two-Way ANOVA, there is a statistically significant relationship between the rpm values and the discs. The 3M group showed the highest roughness value at all rpm speeds. Shofu group at 15k, 20k rpm, Bisco group at 10k, 15k, 20k rpm, the Kerr group at 15k, 20k rpm showed the lowest roughness value and had roughness close to the surfaces finished with a mylar strip. The smoothest surfaces were obtained at 15k rpm, even though polishing discs from different brands were used. It was also observed that 5k and 20k rpm polishing speeds can increase the surface roughness of the nanohybrid resin composite material. [ABSTRACT FROM AUTHOR]

This study aimed to assess the green corrosion inhibitor effect of the compound known as vitamin B6 and called pyridoxine hydrochloride (PYB6) on mild steel in 1.0 M HCl solution by some electrochemical techniques such as linear polarization resistance (LPR), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) for various concentrations and durations. In order to examine the interplay between PYB6 and mild steel surface, various adsorption isotherms were tried and the best correlation constant among them was acquired by Langmuir adsorption isotherm. Experimental data calculated by the EIS method showed that the lowest inhibition efficiency value was 70.7% for 1.0 × 10−5 M PYB6 solution concentration after one hour of immersion, while the highest inhibition efficiency value was 96.8% for 1.0 × 10−3 M PYB6 solution concentration after 48 h of immersion. The finding of zero charge potential (PZC) of mild steel was found to be − 0.010 V in the solution containing the highest concentration of PYB6, which supports that the inhibition mechanism creates a protective film layer on the surface of mild steel with protonated PYB6 molecules. The surface analysis of PYB6 onto mild steel in a hydrochloric acid solution was also examined utilizing techniques such as atomic force microscope (AFM) and field emission scanning electron microscope (FE-SEM). It was concluded that PYB6 green inhibitor formed a presentative adsorption film on the surface of mild steel, effectively reducing its corrosion. [ABSTRACT FROM AUTHOR]

Utilizing radio frequency magnetron sputtering, we successfully fabricated nickel oxide thin films with different thickness (from 80 to 270 nm), and conducted an in‐depth examination of their structural, morphological, optical, and electrical properties. The crystal structure and surface roughness were determined using x‐ray diffraction (XRD) and atomic force microscopy (AFM), respectively. The XRD analyses showed that the films were composed of cubic nickel oxide, exhibiting a notable orientation along the (200) direction. This crystal texture partially increased when the film thickness reached 270 nm. In addition, a direct correlation between film thickness and crystallite size was observed, with the latter increasing as the former did. AFM analysis provided insights into the surface morphology, revealing metrics like the bearing area, 3D surfaces intersections, and statistical properties of surface height. These insights underscore the relationship between film thickness and surface properties, which in turn influence the overall electrical, and prominently, optical properties of the films. Employing transmittance UV–visible spectroscopy, we characterized the optical behavior of these films, noting a proportional increase in refractive index with film thickness. Additionally, resistivity was observed to increase concomitantly with film thickness. In conclusion, the deposition process's film thickness acts as a pivotal parameter for fine‐tuning the structural, morphological, and optical properties of nickel oxide thin films. This knowledge paves the way for optimizing nickel oxide‐based devices across various applications. Research Highlights: We synthesized and characterized of p‐type semiconducting NiO thin films sputtered on substrates by using RF magnetron sputtering with different thickness.Advanced crystalline structures and fractal features extracted from XRD and AFM analysis. The 2D and 3D surface analysis of the samples indicates a complex structure with an imperfect self‐similarity that suggests a multifractal structure.We represented graphically the relative representation of higher geometric objects in the AFM image.We attributed the optical and electrical properties of the samples to the crystallite size, and the concurrent reduction in oxygen vacancies and crystalline defects within the films. [ABSTRACT FROM AUTHOR]

Catheter surgery is an effective treatment for vascular disease and has been investigated from a tribological perspective to prevent vascular damage. Endothelial glycocalyx layer (EGL), which is present on the most superficial surface of vascular endothelial cells plays an important role in maintaining vascular homeostasis, but, during catheter surgery, they are affected by frictional stimulation caused by direct contact with the catheter. In this study, to investigate and discuss the effects of frictional stimulation on the surface properties of vascular endothelial cells, we conducted nano friction tests using atomic force microscopy (AFM) on the surface of vascular endothelial cells. and evaluated mechanical properties, interaction structure, and surface properties of vascular endothelial cells and EGL. The results show that the elastic modulus of endothelial cells increased after the nano friction test. It was also found that EGL was worn away after several slides and the friction coefficient of vascular endothelial cells increased with the wear of the EGL. Furthermore, the adhesion force of endothelial cells increased by the wear of EGL. Besides that, the amount of adsorption to fatal bovine serum (FBS) was also examined using the QCM-D method, and a trend toward increased adsorption was observed for cells without EGL compared to cells with EGL.

(1-x)PVDF/(x)LFO-BTO composite films with weight percentages (x = 0, 0.05, 0.1 and 0.15) were prepared by solution casting method. Phase identification was carried out using the X-ray diffraction (XRD) technique revealing different phases (α, β & γ) of PVDF. FTIR results confirmed the presence of different vibrational modes and phases including PVDF phases. AFM and SEM were used to investigate the surface & morphological analysis, the results showed that the surface roughness increased with the concentration of LFO-BTO into PVDF films. From optical absorption spectra, the direct band gap and indirect band gap energies of the PVDF/LFO-BTO were evaluated by incorporating Tauc's relation. The composites experienced a reduction in band gap upon the addition of 0 - 15 wt% of LFO-BTO with an increasing trend in Urbach's energy. The dielectric investigations revealed elevated dielectric constant values across all composites at lower frequency ranges, attributed to interfacial polarization. Specifically, the dielectric constant of 15 % wt of LFO-BTO was found to be much higher (6 times more than the pristine PVDF). Additionally, the dielectric loss was suppressed with increasing filler concentration within the frequency range of 1 KHz to 1 MHz. Impedance spectroscopy analysis depicted a distinctive semi-circular pattern that was linked to the underlying conduction mechanism. The behaviour of ac-conductivity revealed the conduction process following the Nyquist plot. DTA-TGA analysis showed a notable improvement in thermal stability with increasing concentration in the PVDF matrix. [ABSTRACT FROM AUTHOR]

In this study, a Titanium (Ti) doped α-Fe 2 O 3 (hematite) thin layer was synthesized onto a glass substrate, employing the simultaneous DC and RF magnetron sputtering method. The investigation focused on examining specific physical properties of the film. The optical, structural, morphological, and elemental features of the resulting Ti-doped α-Fe 2 O 3 thin film were characterized using different characterization techniques. The XRD studies indicated a rhombohedral crystal structure in the studied thin film. The calculation of the E g value for the thin film, based on absorption measurements, resulted in a value of 2.19 eV. Raman peaks were identified within the range of 218 cm−1 to 1300 cm−1. According to SEM images, the thin film exhibited a uniform surface morphology across the substrate. AFM images revealed a low root mean square (RMS) roughness value, indicating a smooth Ti:Fe 2 O 3 thin film surface. [ABSTRACT FROM AUTHOR]

Cadherins are calcium dependent adhesion proteins that establish and maintain the intercellular mechanical contact by bridging the gap between adjacent cells. Desmoglein-2 (Dsg2) and desmocollin-2 (Dsc2) are tissue specific cadherin isoforms of the cell-cell contact in cardiac desmosomes. Mutations in the DSG2 -gene and in the DSC2 -gene are related to arrhythmogenic right ventricular cardiomyopathy (ARVC) a rare but severe heart muscle disease. Here, several possible homophilic and heterophilic binding interactions of wild-type Dsg2, wild-type Dsc2, as well as one Dsg2- and two Dsc2-variants, each associated with ARVC, are investigated. Using single molecule force spectroscopy (SMFS) with atomic force microscopy (AFM) and applying Jarzynski's equality the kinetics and thermodynamics of Dsg2/Dsc2 interaction can be determined. The free energy landscape of Dsg2/Dsc2 dimerization exposes a high activation energy barrier, which is in line with the proposed strand-swapping binding motif. Although the binding motif is not affected by any of the mutations, the binding kinetics of the interactions differ significantly from the wild-type. While wild-type cadherins exhibit an average complex lifetime of approx. 0.3 s interactions involving a variant consistently show - lifetimes that are substantially larger. The lifetimes of the wild-type interactions give rise to the picture of a dynamic adhesion interface consisting of continuously dissociating and (re)associating molecular bonds, while the delayed binding kinetics of interactions involving an ARVC-associated variant might be part of the pathogenesis. Our data provide a comprehensive and consistent thermodynamic and kinetic description of cardiac cadherin binding, allowing detailed insight into the molecular mechanisms of cell adhesion. [Display omitted] • Integrity of heart muscle tissue relies on weak molecular bonds between cadherins. • Single molecule force spectroscopy reveals cadherin binding kinetics. • Wild-type cadherin bonds exhibit characteristic fast (re-) binding kinetics. • Specific cardiomyopathy associated cadherin variants slow binding kinetics. • Impaired molecular dynamics could be a cardiomyopathy-specific pathomechanism. [ABSTRACT FROM AUTHOR]

Graphene films,as a two-dimensional material,are excellent lubricants for improving the tribomechanical properties of micro/nano electro-mechanical systems ( MEMS/NEMS) . In order to investigate the influence of substrate material and graphene layer number on its friction reduction performance,this paper investigates the influence of graphene layer number on the friction reduction effect by preparing graphene coatings with different layer numbers on different substrates and using a combination of atomic force microscopy ( AFM) experiments and molecular dynamics ( MD) simulations. And by establishing the analytical model of the friction performance of graphene coatings with different layer numbers,it was investigated that the interlayer slip of graphene is the main factor to produce the wear reduction. The results show that the graphene coating has excellent wear reduction effect on both silicon substrate and copper substrate under different loads,and the friction decreases gradually with the increase of the number of graphene layers,and reaches the optimal 99. 3% wear reduction effect when the number of graphene layers is more than 10. The simulation analysis reveals that as the number of layers increases,the dry friction between graphene and substrate transforms into interlayer friction of graphene and generates interlayer shear slip,and the interlayer slip of graphene is the main factor leading to the excellent wear reduction performance of multilayer graphene. [ABSTRACT FROM AUTHOR]