Changes In Surface Morphology Research Articles

Understanding the Air‐Exposure Degradation Chemistry of the Sacrificial Cathode Additive Li5FeO4 for Li‐Ion Batteries

AbstractLi5FeO4 (LFO) is emerging as a promising prelithiation additive due to the high lithium donor capacity (>700 mAh g−1), cheap raw materials, good environmental adaptability, and reliable synthesis approach. However, LFO suffers from extremely poor air stability and the underlying mechanism remains elusive. Herein, LFO is subjected to different atmospheres (the main component of air) of O2, CO2, N2, and 30% humidity air to unravel its reaction mechanism with air and the interfacial chemistry. It is found that Li+ ions will escape from the LFO crystal lattice to construct Li2O, Li2CO3, and LiOH impurity phases with an obvious change of LFO surface morphology in contact with O2, CO2, and humidity air. These insulating species remarkedly inhibit Li+ ion diffusion from the material and thus lead to an increment of interfacial impedance and an apparent capacity degradation. Consequently, the initial charging capacity decays rapidly from 681.5 to 169.4 mAh g−1 (under O2) and to 54.8 mAh g−1 (under CO2), respectively. In this regard, a facile coating strategy is proposed on the surface of LFO to effectively improve its air stability.

Intracystic injection of large surface area microparticle paclitaxel for chemoablation of intraductal papillary mucinous neoplasms: Insights from an expanded access protocol

AimsA novel large surface area microparticle paclitaxel (LSAM-PTX) has unique properties of long retention in cystic spaces while maintaining high drug concentration. We prospectively evaluated the safety and response of EUS-guided fine needle injection (EUS-FNI) of LSAM-PTX to chemoablate branch duct (BD)-IPMNs. MethodsSubjects diagnosed with BD-IPMNs exhibiting at least one worrisome criteria and considered non-surgical were enrolled in a multicenter clinical trial (NCT03188991) and subsequently included in an Expanded Access Protocol (EAP) where they received EUS-FNI of LSAM-PTX (15 mg/mL). ResultsSix BD-IPMNs measuring (mean ± SD) 3.18 ± 0.76 cm in diameter among 5 subjects (mean age: 66 years) were treated by EUS-FNI of LSAM-PTX. A mean of 4 doses of LSAM-PTX (mean dose/cyst: 73 ± 31 mg) were administered, and subjects were followed for up to 32 months. The mean volume reduction/cyst ranged from 42 to 89% (9.58 ± 5.1 ml to 2.2 ± 1.1 ml (p = 0.016)). The mean surface area reduction ranged from 31 to 83% (21.9 ± 8.7 cm2 to 5.7 ± 2.5 cm2 (p = 0.009)). Higher dosing-frequency of EUS-FNI of LSAM-PTX significantly correlated with a reduction in cyst volume (R2 = 0.87, p = 0.03) and surface area (R2 = 0.83, p = 0.04). Comparing pre- and post-ablation samples, molecular analysis of the cyst fluid revealed a loss of IPMN-associated mutations in 5 cases (83.3%), while reemergence was observed in 1 case and persistence in 1 case. Intracystic changes (fibrosis/calcification) were observed in 83.3% (n = 5). One subject developed mild acute pancreatitis (1 of 22 EUS-FNIs of LSAM-PTX). ConclusionIn this EAP, EUS-FNI of LSAM-PTX into BD-IPMNs was safe and resulted in volume and surface area reduction, morphological changes, and loss of pathogenic mutations.

Molecular Insight into the Ternary Complex Formation between Ethambutol, Isoniazid and β‐Cyclodextrin

AbstractLong term intake of antituberculosis drugs will lead to severe adverse reactions that will ultimately deteriorate a patient's health and well‐being. With that, the ternary inclusion complex was explored, whereby β‐cyclodextrin (β‐CD) was chosen as the supramolecular host carrier to accommodate two kinds of first line antituberculosis guest drug molecules simultaneously, namely isoniazid (INH) and ethambutol (ETB) which would provide many therapeutic benefits. The inclusion complex of β‐CD/INH/ETB was prepared using solvent evaporation method. Fourier transform infrared spectroscopy (FT‐IR), proton nuclear magnetic resonance spectroscopy (1H‐NMR), and 2‐dimensional nuclear Overhauser effect spectroscopy (2D‐NOESY) NMR were used to investigate the functional groups and structure of the complex. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) were employed to study the surface morphology and crystallinity changes during complex formation. Thermogravimetric analysis (TGA) was performed to investigate the thermal properties of the complex. FT‐IR and both types of NMR results had revealed the successful penetration of both the drug molecules into the β‐CD cavity. SEM images and XRD spectra had shown a drastic change in surface structure and reduction in crystallinity during complex formation, which had indicated successful formation of a new compound. TGA had proven that the complex had significantly greater thermal stability as compared to the pure components. Molecular dynamics (MD) and molecular docking simulations were also performed to understand the molecular interaction between β‐CD, INH, and ETB. Through precise calculations of interaction and binding energies, β‐CD/INH/ETB was found to be a more stable inclusion complex compared to the binary β‐CD/INH and β‐CD/ETB complexes.

Optical characterization and electrical behavior of bismuth oxide nanoparticles modified PEO/PVP matrix via laser ablation for electrical applications

The effect of bismuth oxide (Bi2O3) nanoparticles synthesized via laser ablation route on polymeric materials composed of PEO/PVP blend was studied. The future utilization of these materials is highly dependent on their structural, morphology, thermal, and electrical qualities being improved. The observed disappearance of the patterns at 2θ = 19.6° and 23.7° in XRD can be attributed to the elevated temperature resulting from the laser beam, which in turn causes the breakup of PEO-PVP chains which confirm the incorporation of Bi2O3 nanoparticles in PEO-PVP complex. The crystal size of Bi2O3 nanoparticles has been determined to be 20 nm. FT-IR spectra confirms the interactions between Bi2O3 nanoparticles and PEO-PVP matrix. Ultraviolet/Visible (UV–Vis) analysis obtains reducing in band-gap by increasing Bi2O3 nanoparticles concentration upon the blend. The change in surface morphology is confirmed by FESEM images by appearing white spots on the surface of PEO-PVP and increasing cluster size of PEO of composite by addition of Bi2O3 NPs. Also, the thermal stability is improved by shifting Thermogravimetric (TG) curves doped with Bi2O3 NPs toward higher temperature by increasing ablation time. Electrical conductivity results show reducing in both dielectric constant (ε′) and dielectric loss (ε'') as the frequency rises. The modifications in both optical and electrical conductivity characterization lead to optimizing compositions in electrical applications.

Evaluation of in vitro dissolution profiles of modified-release metoprolol succinate tablets crushed using mortar and pestle technique

PurposeClinical practice guidelines advise against crushing modified-release dosage forms. Metoprolol succinate modified-release (MS-MR) tablets are commonly crushed in clinical practice to facilitate administration to patients with swallowing difficulties or using feeding tubes. To date, the effect of this practice remains unexplored. The in vitro effects of crushing commercially available MS-MR tablets were explored using a holistic approach. MethodsDissolution profiles of crushed versus whole MS-MR tablets were compared. Tablets were crushed to powder state using pragmatic method mimicking hospital practices. For standardization purposes, the same operator, duration (60 seconds), hand, and mortar-pestle apparatus were used. Dissolution studies were conducted per U.S. Pharmacopeia at pH 1.2, pH 4.5, and pH 6.8 with USP apparatus 2 (paddle) at rotation speed of 50 rpm at 37±0.5 °C in 500 mL dissolution media. Samples were withdrawn at predetermined time points. Percent drug dissolved was measured by validated UV–vis Spectrophotometry. Comprehensive analysis of the dissolution data was conducted using model-independent, model-dependent, and ANOVA-based approaches (SPSS v.23 at α=0.05). Similarity (f2) and difference (f1) factors were calculated to compare the dissolution profiles between crushed (CT) and whole tablets (WT). Goodness of fit (GOF) analysis examined the compliance between in vitro dissolution behaviors and several drug release models. Model selection was based on GOF plots, Akaike criteria and adjusted coefficient of determination (R2adj). Imaging and particle size distribution analysis were conducted to examine associated surface and morphologic changes. ResultsThe dissolution profiles were not similar at pH 4.5 (f2=45.43, f1=18.97) and pH 6.8 (f2=31.47, f1=32.94). CT best fitted with Higuchi (pH 1.2: R2adj=0.9990), Weibull (pH 4.5: R2adj=0.9884), and Korsmeyer-Peppas (pH 6.8: R2adj=0.9719). Contrastingly, WT best fitted with Hopfenberg (pH 1.2: R2adj=0.9986), logistic (pH 4.5: R2adj=0.9839) and first-order (pH 6.8: R2adj=0.9979) models. A significant difference in the dissolution profiles was found between CT and WT using multivariate analysis of variance per time points and between the tablet forms (p=0.004). This was confirmed by unparalleled dissolution profiles. Crushing resulted in variations in particle size and surface morphological changes to the micropellets. ConclusionCrushing practices change the dissolution profile of MS-MR tablets by deforming the surface morphology of embedded micropellets. Amounts of drug dissolved between CT and WT were not the same at the compared time points across gastrointestinal pH ranges. This suggests potential clinical impact on plasma-concentration profiles of critically ill patients using feeding tube.

Swift heavy ion irradiation effects on tungsten carbide films

Tungsten carbide (WC) is an important material to study for various applications in extreme environments due to its radiation-resistant properties and high mechanical strength. Due to its excellent properties such as high hardness, strength, and wear resistance, it is also being considered lately as a plasma facing component in nuclear fusion reactors. To study the response of this material in extreme radiation environments, WC films prepared using RF sputtering technique were irradiated with 100 MeV Ag8+ ions in the present work. The irradiation was carried out at three different fluences: 3 × 1012, 1 × 1013, and 3 × 1013 ions/cm2. Rutherford Backscattering Spectrometry (RBS) was performed to determine the stoichiometry and thickness of the pristine film. To study the irradiation-induced modifications, glancing angle X-ray diffraction (GAXRD), field emission scanning electron microscopy (FE-SEM), High Resolution Transmission Electron Microscopy (HRTEM), and Raman spectroscopy were performed on the pristine and irradiated samples. GAXRD of the pristine and irradiated samples revealed grain size reduction accompanied with reduced crystallinity with increasing ion fluence which was further manifested in HRTEM measurements and Raman spectroscopy measurements. Change in surface morphology due to the ion irradiation was observed in FE-SEM. These modifications have been explained using thermal-spike and TRIM simulations which showed that although the swift heavy ions irradiation did not result in track formation in the WC films, it caused radiation damage which may be attributed to the synergistic effect of electronic and nuclear energy loss mechanisms. These results might be crucial for a fundamental understanding of the radiation resistance of WC thin films and its application in different radiation environments.

Evaluation of the application of chemically adapted gourd fibre in polyester composite fabrication

Purpose Gourd fibres (GF) are a natural biodegradable fibre material with excellent mechanical properties and high tensile strength. The use of natural fibres in composite materials has gained popularity in recent years due to their various advantages, including renewability, low cost, low density and biodegradability. Gourd fibre is one such natural fibre that has been identified as a potential reinforcement material for composites. However, it has low surface energy and hydrophobic nature, which makes it difficult to bond with matrix materials such as polyester. To overcome this problem, chemically adapted gourd fibre has been proposed as a solution. Chemical treatment is one of the most widely used methods to improve the properties of natural fibres. This research evaluates the feasibility and effectiveness of incorporating chemically adapted gourd fibre into polyester composites for industrial fabrication. The purpose of this study is to examine the application of chemically modified GF in the production of polyester composite engineering materials. Design/methodology/approach This work aims to evaluate the effectiveness of chemically adapted gourd fibre in improving the adhesion of gourd fibre with polyester resin in composite fabrication by varying the GF from 5 to 20 wt.%. The study involves the preparation of chemically treated gourd fibre through surface modification using sodium hydroxide (NaOH), permanganate (KMnO4) and acetic acid (CH3COOH) coupling agents. The mechanical properties of the modified fibre and composites were investigated. It was then characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to determine the changes in surface morphology and functional groups. Findings FTIR characterization showed that NaOH treatment caused cellulose depolymerization and caused a significant increase in the hydroxyl and carboxyl groups, showing improved surface functional groups; KMnO4 treatment oxidized the fibre surface and caused the formation of surface oxide groups; and acetic acid treatment induced changes that primarily affected the ester and hydroxyl groups. SEM study showed that NaOH treatment changed the surface morphology of the gourd fibre, introduced voids and reduced hydrophilic tendencies. The tensile strength of the modified gourd fibres increased progressively as the concentration of the modification chemicals increased compared to the untreated fibres. Originality/value This work presents the designed composite with density, mechanical properties and microstructure, showing remarkable improvements in the engineering properties. An 181.5% improvement in tensile strength and a 56.63% increase in flexural strength were got over that of the unreinforced polyester. The findings from this work will contribute to the understanding of the potential of chemically adapted gourd fibre as a reinforcement material for composites and provide insights into the development of sustainable composite materials.

An innovative method for the detection of alpha synuclein, a potential biomarker of Parkinson's disease: quartz tuning fork-based mass sensitive immunosensor design.

An innovative biosensing fabrication strategy has been demonstrated for the first time using a quartz tuning fork (QTF) to develop a practical immunosensor for sensitive, selective and practical analysis of alpha synuclein protein (SYN alpha), a potential biomarker of Parkinson's disease. Functionalization of gold-coated QTFs was carried out in 2 steps by forming a self-assembled monolayer with 4-aminothiophenol (4-ATP) and conjugation of gold nanoparticles (AuNPs). The selective determination range for SYN alpha of the developed biosensor system is 1-500 ng mL-1 in accordance with the resonance frequency shifts associated with a limit of detection of 0.098 ng mL-1. The changes in surface morphology and elemental composition were evaluated using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and energy-dispersive X-ray spectroscopy (EDX). The remarkable point of the study is that this QTF based mass sensitive biosensor system can capture the SYN alpha target protein in cerebrospinal fluid (CSF) samples with recoveries ranging from 92% to 104%.

Green synthesis approach using deep eutectic solvents to enhance the surface functional groups on porous carbon for CO2 capture

This study explores the potential of green solvents using amino acids-based deep eutectic solvents to alter surface functionality of activated carbon thus enhancing the carbon dioxide (CO2) adsorption capacity. Green solvent is prepared by mixing an amino acid (L-Arginine) with ethylene glycol to form amino acid-based deep eutectic solvents. Amino acid-based deep eutectic solvents were used to modify the surface functionalities of activated carbon derived from palm shell waste. The change in surface functional groups and surface morphology of the modified activated carbon samples were characterized by Fourier-transform infrared spectroscopy and Scanning electron microscopy-energy dispersive X-ray analysis. Then, CO2 removal performance was performed using a packed-bed CO2 adsorption reactor to evaluate CO2 breakthrough time and adsorption capacity. CO2 adsorption experiments were measured at a certain temperature (25–45°C), at a fixed feed flow rate and CO2 concentration of 200 mL/min and 15%. It was observed that modified activated carbon showed the highest breakthrough time (15.2 min) compared to raw palm shell (5.2 min) at an adsorption temperature of 25°C. CO2 breakthrough times significantly decreased with increasing adsorption temperature because of physical adsorption.

RF Characterisation of Laser Treated Copper Surfaces for the Mitigation of Electron Cloud in Accelerators

In accelerator beam chambers and RF waveguides, electron cloud and multipacting can be mitigated effectively by reducing the secondary electron yield (SEY). In recent years, it has been established that laser-engineered surface structuring is a very efficient method to create a copper surface with a SEY maximum close to or even below unity. Different laser pulse durations, from nanoseconds to picoseconds, can be used to change surface morphology. Conversely, the characteristics that minimise the SEY, such as the moderately deep grooves and the redeposited nanoparticles, might have unfavourable consequences, including increased RF surface resistance. In this study, we describe the techniques used to measure the surface resistance of laser-treated copper samples using an enhanced dielectric resonator with 12 cm diameter sample sizes operating in the GHz range. The quantification basis lies in a non-contact measurement of the high-frequency losses, focusing on understanding the variation of surface resistance levels depending on the specifics of the treatment and possible post-treatment cleaning procedures.

Characterization of the Fels Landslide (Alaska) Using Combined Terrestrial, Aerial, and Satellite Remote Sensing Data

The characterization of landslides located in remote areas poses significant challenges due to the costs of reaching the sites and the lack of reliable subsurface data to constrain geological interpretations. In this paper, the advantages of combining field and remote sensing techniques to investigate the deformation and stability of rock slopes are demonstrated. The characterization of the Fels landslide, a large, slowly deforming rock slope in central Alaska, is described. Historical aerial imagery is used to highlight the relationship between glacier retreat and developing instability. Airborne laser scanning (ALS) and Structure-from-Motion (SfM) datasets are used to investigate the structural geological setting of the landslide, revealing a good agreement between structural discontinuities at the outcrop and slope scales. The magnitude, plunge, and direction of slope surface displacements and their changes over time are studied using a multi-temporal synthetic aperture radar speckle-tracking (SAR ST) dataset. The analyses show an increase in displacement rates (i.e., an acceleration of the movement) between 2010 and 2020. Significant spatial variations of displacement direction and plunge are noted and correlated with the morphology of the failure surface reconstructed using the vector inclination method (VIM). In particular, steeper displacement vectors were reconstructed in the upper slope, compared to the central part, thus suggesting a change in basal surface morphology, which is largely controlled by rock mass foliation. Through this analytical approach, the Fels landslide is shown to be a slow-moving, compound rockslide, the displacement of which is controlled by structural geological features and promoted by glacier retreat.

Formulation of Ensulizole with Beta-Cyclodextrins for Improved Sunscreen Activity and Biocompatibility

In today's context, prolonged exposure to sunlight is widely recognized as a threat to human health, leading to a range of adverse consequences, including skin cancers, premature skin aging, and erythema. To mitigate these risks, preventive actions mainly focus on advocating the application of sunscreen lotions and minimizing direct exposure to sunlight. This research study specifically centered on ensulizole (ENS), a prominent ingredient in sunscreens. The objective was to create inclusion complexes (ICs) with Beta-cyclodextrin (B–CD) and its hydroxypropyl derivatives (H–CD). Using phase solubility measurements, we determined that both B–CD and H–CD form 1:1 stoichiometric ICs with ENS. Proton nuclear magnetic resonance spectral (1H NMR) analysis confirmed that the phenyl portion of ENS is encapsulated within the B–CD cavity. Significant changes in surface morphology were observed during the formation of these ICs compared to ENS and CDs alone. Quantum mechanical calculations were employed to further support the formation of ICs by providing energy data. Particularly, the photostability of the ENS:B–CD ICs remained intact for up to four hours of UV exposure, with no significant alterations in the structure of ENS. Furthermore, comprehensive biocompatibility assessments yielded encouraging results, suggesting the potential application of these inclusion complexes in cosmetics as a UVB sunscreen. In summary, our research underscores the successful creation of inclusion complexes characterized by enhanced photostability and safe biocompatibility.

Use of NIR/NaBH4 combinatorial techniques for simultaneous and high-efficient adsorption of heavy metal ions from contaminated water by Chitosan/Au Janus microdisks

This article discusses the creation of a disk-shaped microsorbent with Janus morphology made with chitosan and coated with gold on one side using the sputtering technique. The aim of the research is to explore how sodium borohydride and near-infrared (NIR) light can enhance the adsorption of heavy metal ions by our synthesized adsorbent. The changes in surface morphology and composition of the chitosan part of Janus microdisks, after acid treatment and crosslinking reaction, before and after adsorption process were investigated through scanning electron microscopy (SEM). The chitosan/Au Janus microdisks were utilized in auto-catalyzed adsorption of heavy metals including, Pb, Cu, Cd, Zn, and Ni, in the presence of sodium borohydride. The isotherm, kinetic, and thermodynamic curves of adsorbance in the presence of metals were investigated. In addition, the performance of Janus microsorbents in the co-existing ions solution was studied under different conditions. The synthesized microsorbents can remove Cu ions selectively from contaminated water (>99 %) with the help of sodium borohydride. In addition, the NIR light irradiation exhibited a synergistic effect on the adsorption of Cd, Ni, and Pb ions in the presence of sodium borohydride. The borohydride ions can change the surface charge of microdisks after adsorption on their surface and increase the adsorption rate of metal cations. In addition, NIR light irradiation can accelerate the reaction of sodium borohydride with metal ions.

Intenzitet toplinske modifikacije topolovine. Dio 1

Wood heat treatment is an environmentally friendly method, and the heat-treated wood properties are closely related to thermal modification intensity. This study focuses on the 0-3 mm surface layer (SL) of poplar wood heat treated at 160~220 °C. The modification intensity, including surface color, hardness, chemical component and morphological changes of the SL, was evaluated. The findings of this research showed that the color difference of the poplar wood before and after heat treatment (ΔE*1) increased; the color difference between up-surface and down-surface of the SL (ΔE*2) also increased with the treatment temperature. Consequently, the surface hardness (HR) decreased with the increase of treatment intensity. When the treatment temperature was higher than 160 °C, the up-surface and down-surface of the SL were statistically different in color. Chemical component analysis revealed that the heat treatment degrades wood components, especially the hemicellulose, and correlation analysis showed a significant correlation between the change rate of hemicellulose and the ΔE*1 or HR value; the prediction functions have been established at a high confidence level of 0.99. Overall, the thermal modification intensity of the heat-treated surface layer (SL) of poplar wood varies, and the HR and ΔE*1 value could be used to characterize and predict the modification intensity and degree of thermal degradation of the surface layer of heat-treated poplar wood.

Tribological glazing evolution of fixed abrasive pad under different polishing solution conditions

PurposeThis study aims to clarify the influence mechanism of polishing solution type on the glazing evolution of fixed abrasive pad under different interfacial pressure conditions.Design/methodology/approachThe tribological experiments were carried out on the friction and wear machinery with W3-5 diamond fixed abrasive pad and quartz glass workpiece under three polishing solution types of five pressure conditions. The changes of surface morphology, porosity and hardness of fixed abrasive pad were detected by white light interferometer, optical microscope and shore hardness tester.FindingsThe results showed that the glazed phenomenon of fixed abrasive pad is occurred after a certain time, which is more obvious with the increasing of interfacial pressures. The polishing solution type has a significant effect on the glazing time, although the glazed phenomenon is inevitable. The mechanism of it is that the micro-convex peaks on the surface of the fixed abrasive pad are easily wear, and the pores are blocked by the accumulation of waste debris generated during the experiment process. Thus, a smooth and high-density hard layer is formed on the surface of the fixed abrasive pad which induces the decreasing of the friction coefficient and surface roughness value. For selected polishing solution types, the wear rate of micro-convex peaks is different due to the corrosion action difference with polishing pad surface.Originality/valueThe main contribution of this work is to provide a new investigating method for further understanding the glazing evolution mechanism of fixed abrasive pad.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0257/

Influence of shock waves on bifunctional nickel particles: Enhancing magnetic properties and supercapacitor applications

In the present study, shock-wave impact experiments were conducted to investigate the structural properties of nickel metal powder when exposed to shock waves. Both X-ray diffractometry and scanning electron microscopy were used to evaluate the structural and surface morphological changes in the shock-loaded samples. Notably, the experimental results revealed variations in lattice parameters and cell structures as a function of the number of shock pulses and the increasing volume. The transition occurred from P2 (100 shocks) to P3 (200 shocks). Remarkably, P5 (400 shocks) exhibited attempts to return to its initial state, and intriguingly, P4 displayed characteristics reminiscent of the pre-shock condition. Additionally, significant morphological changes were observed with an increase in shock pulses. Magnetic measurements revealed an increase in magnetic moment for P2, P3, and P4, but a return to the original state was observed for P5. Moreover, the capacitance exhibited an upward trend with increasing shock pulses, except for P5, where it experienced a decline. These findings underscore the significant impact of even mild shock waves on the physical and chemical characteristics of bifunctional nickel particles. This research sheds light on the potential applications of shock wave-induced structural changes in enhancing the magnetic properties and supercapacitor performance of nickel particles.

Study of amur cork tree bark extract-dyed paper under artificial UVA irradiation

Some ancient Chinese paper artifacts dyed with amur cork tree bark extracts are currently preserved to different extents in museums and libraries worldwide. As traditional natural plant dyes, the long-term performance of the amur cork tree bark extract-dyed handmade paper has been questioned under a preserved environment. The photodegradation process of the extract-dyed papers was examined under accelerating artificial UVA irradiation conditions according to China national standard-paper and board- accelerated aging (exposure to light). Changes during aging were analyzed by optical observation and scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR), pH, and tensile strength and folding endurance tests. The results showed that the main components from extracted dyes played an important role in affecting the photodegradation properties of dyed paper. The changes in surface color, pH, morphology and mechanical properties after the artificial UVA accelerated degradation tests revealed that a suitable concentration of the extract dyes for maintaining the long-term irradiation stability of the paper is important.

A New Promising Material for Biological Applications: Multilevel Physical Modification of AgNP-Decorated PEEK.

In the case of polymer medical devices, the surface design plays a crucial role in the contact with human tissue. The use of AgNPs as antibacterial agents is well known; however, there is still more to be investigated about their anchoring into the polymer surface. This study describes the changes in the surface morphology and behaviour in the biological environment of polyetheretherketone (PEEK) with immobilised AgNPs after different surface modifications. The initial composites were prepared by immobilising silver nanoparticles from a colloid solution in the upper surface layers of polyetheretherketone (PEEK). The prepared samples (Ag/PEEK) had a planar morphology and were further modified with a KrF laser, a GaN laser, and an Ar plasma. The samples were studied using the AFM method to visualise changes in surface morphology and obtain information on the height of the structures and other surface parameters. A comparative analysis of the nanoparticles and polymers was performed using FEG-SEM. The chemical composition of the surface of the samples and optical activity were studied using XPS and UV-Vis spectroscopy. Finally, drop plate antibacterial and cytotoxicity tests were performed to determine the role of Ag nanoparticles after modification and suitability of the surface, which are important for the use of the resulting composite in biomedical applications.

Altered cortical and subcortical morphometric features and asymmetries in the subjective cognitive decline and mild cognitive impairment.

This study aimed to evaluate morphological changes in cortical and subcortical regions and their asymmetrical differences in individuals with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). These morphological changes may provide valuable insights into the early diagnosis and treatment of Alzheimer's disease (AD). We conducted structural MRI scans on a cohort comprising 62 SCD patients, 97 MCI patients, and 70 age-, sex-, and years of education-matched healthy controls (HC). Using Freesurfer, we quantified surface area, thickness, the local gyrification index (LGI) of cortical regions, and the volume of subcortical nuclei. Asymmetry measures were also calculated. Additionally, we explored the correlation between morphological changes and clinical variables related to cognitive decline. Compared to HC, patients with MCI exhibited predominantly left-sided surface morphological changes in various brain regions, including the transverse temporal gyrus, superior temporal gyrus, insula, and pars opercularis. SCD patients showed relatively minor surface morphological changes, primarily in the insula and pars triangularis. Furthermore, MCI patients demonstrated reduced volumes in the anterior-superior region of the right hypothalamus, the fimbria of the bilateral hippocampus, and the anterior region of the left thalamus. These observed morphological changes were significantly associated with clinical ratings of cognitive decline. The findings of this study suggest that cortical and subcortical morphometric changes may contribute to cognitive impairment in MCI, while compensatory mechanisms may be at play in SCD to preserve cognitive function. These insights have the potential to aid in the early diagnosis and treatment of AD.

Optimization of Plasma Activated Water Extraction of Pleurotus ostreatus Polysaccharides on Its Physiochemical and Biological Activity Using Response Surface Methodology.

This study focused on optimizing the extraction of P. ostreatus polysaccharides (POPs) using plasma-activated water (PAW). A single factor and response surface methodology were employed to optimize and evaluate the polysaccharide yield, physiochemical characteristics, and biological activities of POPs. The observed findings were compared to those obtained by the conventional hot water extraction method (100 °C, 3 h), as the control treatment. The optimal extraction conditions were obtained at 700 W PAW power, 58 s treatment time, 1:19 sample-to-water ratio, and 15 L/min gas flow rate. In these conditions, the PAW-treated samples experienced changes in surface morphology due to plasma etching, leading to a 288% increase in the polysaccharide yield (11.67%) compared to the control sample (3.01%). Furthermore, the PAW-treated sample exhibited superior performance in terms of biological activities, namely phenolic compounds (53.79 mg GAE/100 g), DPPH scavenging activity (72.77%), and OH scavenging activity (65.03%), which were 29%, 18%, and 38% higher than those of control sample, respectively. The results highlighted the importance of process optimization and provided new evidence for PAW as an alternative approach to enhance the extraction efficiency of POPs, a novel source of natural antioxidants which enables diverse applications in the food industry.