Thin Layer Research Articles

Influence of Construction Process on Aggregate Spalling Behavior on Ultrathin Waterborne Epoxy Resin Layer

The waterborne epoxy resin (WER) colored antiskid thin layer has been widely used in asphalt pavement to improve driving safety. The tectonic depth determines the antiskid performance of aparticle antiskid type thin layer. The spalling of aggregate from a thin layer may reduce the tectonic depth, thus damaging antiskid performance. The spreading process of aggregate on the WER binder surface plays an important role in the spalling behavior of the thin layer. Herein, the influence of spreading processes on the ceramic aggregate spalling behavior on the WER thin layer was investigated based on laboratory experiments. The abrasion and British Pendulum Number (BPN) tests were employed to evaluate the antispalling and antiskid properties of the WER thin layers with different amounts of WER mortar, coverage rates of first-spread aggregate, and spreading orders of coarse/fine aggregates. Moreover, the tectonic depths of the layers before/after the spalling test were also investigated. The results indicated that the optimal dosage of WER mortar is 2.8 kg/m2. The WER thin layer exhibited better anti-striping property when coarse ceramic aggregate was spread first. The first-spread coverage rate of the aggregate on the WER surface is 70%. The thin layer exhibited a superior antispalling performance according to the resulting scheme, with a spalling rate of 3.77%. The tectonic depth only decreased from 1.87 to 1.80 mm after the spalling test.

Feeding ecology of two wild sympatric canids in protected areas of northeastern Argentina

AbstractThe role of mesocarnivores in wildlife communities tends to be overlooked, which has led to a large gap in natural history knowledge. In northeastern Argentina, two mesocarnivore foxes, Cerdocyon thous and Lycalopex gymnocercus, live in sympatry in noncompetitive coexistence. Their feeding habits have been studied in many occasions; however, the studies related to trophic variability in a wider spatial scale remain scarce. In this study, we aimed to analyze how the diet of these foxes varies in three protected areas in Argentina: the Mburucuyá National Park (MNP), the “San Nicolás Portal” (SN), and the Natural Reserve Rincón de Santa María (RSM). We collected fecal samples in each area, identified them using thin layer chromatography at species level, and classified the found feeding items to obtained two parameters: occurrence and relative frequency. Furthermore, we compared the diet of the two species in each site and between sites using chi‐square and estimated trophic niche breadth and overlap between the species. We found that both species consumed different food categories, with variable frequencies across study sites. We observed that in each area, the foxes differed in diet composition. However, we found no differences between the diet compositions of C. thous and L. gymnocercus, showing high niche overlap in each site. Here, we show the plasticity of both fox species in changing their diets even with small geographical variation. Both species can coexist even with a high diet overlap, possibly explained by their noncompetitive coexistence which may occur due to the current changes in the ecosystem interactions, or partitioning may exist but on a smaller niche level.

Formulation and Evaluation of Herbal Mouth Wash

The importance of oral and dental hygiene has been known from the beginning of civilization to the 21st century. Patients and dentists are faced with a wide variety of mouthwash products containing a variety of active and inactive ingredients. Making an informed decision about the suitability of a particular product for a particular patient can be a complex task. Many popular herbal products help fight plaque and periodontal disease, but they have only been used for a short time and only as an adjunct to other oral hygiene measures such as brushing and flossing. Natural mouthwashes may offer significant advantages over chemical mouthwashes. If a mouthwash can be developed using natural products that can be easily prepared at home and is safe to use, it could lead to an improvement in people's overall dental health. A variety of natural ingredients and materials have been used in this study. Thin layer chromatography was then performed to confirm the quality of the materials used. Subsequently, physical evaluation, pH measurement, stability studies, thin layer chromatography and antibacterial studies were carried out. The study concluded that the developed herbal mouthwash is a significant, therapeutically effective and suitable drug delivery agent with undoubtedly high potential, albeit at a low cost. Therefore, increased use of herbal preparations is necessary to avoid side effects. This study is an attempt to outline natural substances that can be used as effective mouthwashes.

A comparative evaluation of a commercially available kojic acid and arbutin-containing test product with a test regime in the treatment of hyperpigmentation

Background: The study compared the effectiveness of kojic acid and arbutin-containing lotion (alone) with arbutin-containing facewash and kojic acid and arbutin-containing lotion in the reduction of pigmentation. Methods: The study compared the test product (lotion) and the test regime (lotion + facewash) over a period of 45 days. In both test groups, a thin layer of advance body lotion was applied to the face, neck, and upper trunk. In the test regime group (TRG), these areas were washed with advance facewash before the lotion was applied. Both groups used sunscreen (with a sun protection factor of 50). The primary outcomes measured were (i) skin radiance and skin pigmentation, (ii) skin gloss, and (iii) skin hydration. The secondary outcomes measured were clinical evaluation and a subjective self-assessment for tolerance and perception of the product. Results: The study included 61 participants. The TRG showed a statistically significant increase in skin hydration (at 21 days) and skin gloss compared to the test product group (TPG) (at 21 and 45 days) (p<0.05). The majority of participants in both groups reported a visible reduction in pigmentation and improved facial glow and hydration as compared to baseline. No serious adverse effects were reported. Conclusions: The use of kojic acid and arbutin-containing lotion alone and arbutin-containing facewash with the lotion led to significant improvements in skin radiance, lightening, gloss, and hydration as compared to the baseline, with the TRG showing significantly better clinical results than the TPG in terms of skin hydration and gloss.

EXTRACTION, Extraction, Isolation, Identification and Estimation of Diosgenin by TLC Profiling and UHPLC-LC-SRM Analysis in Three Costus Species

Medicinal plants are utilized for treating many ailments, since ancient times due to their tremendous therapeutic properties. The plant derivatives are used as a raw material for the synthesis of drugs either as a natural or artificial synthetic drug. Costaceae family members are known to possess many medicinal properties few of them are mainly consumed to reduce the blood glucose level and treat many disorders. The sapogenin contained in the rhizome of three Costus species was extracted, identified, and characterized. Young rhizomes were harvested surface sterilized, hydrolyzed; extracted through a soxhlet apparatus and concentrated fractions were subjected to a preliminary phytochemical screening test for saponin, Thin Layer Chromatography, and the UHPLC-MS SRM analysis. The result showed that the maximum yield of the Diosgenin was obtained from the chloroform extract of Costus speciosus. The pharmaceutical analysis in all the three Costus species carried out with isolated saponin was compared with standard Diosgenin. The characterization of isolated diosgenin was done by UHPLC MS and SRM, based on the retention time of all three samples and the comparison with standard Diosgenin. Isolated Diosgenin was quantified through thin layer chromatography with n-hexane: ethyl acetate (7:3) as mobile phase at Rf value of 0.48. The amount of Isolated Diosgenin was estimated by comparing the peak area at a retention time Rt value of 8.5 in all the samples and compared with standard Diosgenin high amount of Diosgenin was found in Costus speciosus rhizome followed by Costus igneus and Costus pictus. The preliminary phytochemical screening and analytical methods involved during the present study were found satisfactory. Thus, the protocol can be used for the extraction of Diosgenin and further used in the synthesis of Drugs. Keywords: Costus pictus, Costus speciosus, Costus igneus, rhizome, TLC, UHPLC-MS, SRM

A comprehensive analysis of morphological and biochemical parameters of <i>Medicago sativa</i> during biotic stress

Background: Parasitism is an abiotic stress that significantly threatens plant growth and severely impacts crop productivity. Plants have developed complicated regulatory mechanisms to cope with stressful conditions, undergoing morphological and biochemical changes. Objective: The article presents the first comprehensive analysis of the Medicago sativa response to the penetration of flowering parasites Orobanche lutea and Cuscuta alba. The outcome of this study aim to enhance crop quality comprehend their bioactive properties and pinpoint optimal strategies for their utilization in preventing and treating human and animal health issues. Methods: Medicago sativa, Orobanche lutea and Cuscuta alba were collected in the Ararat province, located in southeastern Armenia. The plants’ morphological structures and leaf parameters were observed. The prooxidant activity was determined by the potentiometric method. The content of total phenols, flavonoids and catechins were determined by a spectrophotometric method. Pigments were separated and identified using thin layer chromatography and a spectrophotometric method. Results: The in-situ observations of M. sativa plant and ex-situ measurements of its leaves infected by O. lutea and C. alba reveal a significant negative impact on both the reproductive success and the vegetative aspects. Infected plants exhibited minimal inflorescence development, also, substantial reductions in leaf dimensions were observed. The analysis of prooxidant activity revealed that M. sativa exhibits inherent prooxidant properties, which are amplified in the presence of parasites. The influence of dodder on prooxidant activity is much more significant (14-38%) than that of broomrape (8-42%). The percentage changes in total phenolic content were more pronounced in the presence of C. alba, but flavonoid decline was more pronounced in the presence of O. lutea, suggesting a differential impact of the two parasites. Although catechin content was not affected, photosynthetic pigments of the host plant were significantly (28-57%) reduced by the parasites. Conclusion: Findings indicate a clear morphological alteration induced by parasitic infestation. The parasites, particularly O. lutea can cause temporal isolation and allochronic speciation in M. sativa populations. Biochemical analysis highlighted a complex interplay between the host and the parasite. The biochemical impact of the parasite is reflected on the host’s primary and secondary metabolism. The observed morphological and biochemical changes highlight the need for further research to explore potential mitigation strategies, selective herbicide development, and biocontrol measures against parasitic plant infestations in agricultural ecosystems. Keywords: alfalfa; Orobanche lutea; Cuscuta alba; parasites plants; morphophysiological observations; bioactivity.

Goniosynechialysis for Chronic Angle-closure Glaucoma after Extracapsular Cataract Extraction: A Case Report

Purpose: We present a case of goniosynechiolysis in the treatment of chronic angle-closure glaucoma with persistent peripheral anterior synechia (PAS) after extracapsular cataract extraction (ECCE) for phacomorphic glaucoma that remained uncontrolled using topical glaucoma medications.Case summary: A 59-year-old woman presented with right eye pain and visual loss that started 3 days ago. Examination revealed an intraocular pressure (IOP) of 46 mmHg, a narrow central anterior chamber, and peripheral iridocorneal touch, indicative of phacomorphic glaucoma. Although ECCE was performed, PAS was not adequately resolved. Initially, visual acuity, IOP, and visual field were controlled with a single topical glaucoma medication. However, progressive retinal nerve fiber layer thinning and uncontrolled IOP, despite maximal medical therapy. Therefore, goniosynechiolysis was performed at 24 months after ECCE. The procedure reduced IOP from 25 mmHg to 13 mmHg without complications, such as hyphema, cyclodialysis, and fibrin formation.Conclusions: Goniosynechiolysis can be a safe and effective intervention for chronic angle-closure glaucoma with persistent PAS and elevated IOP.

Surface Sulfurization of Cubic Cu2O to Form Cu2S Nanostructure-Decorated Catalysts for Light-enhanced Electrocatalytic H2 Evolution and Photocatalytic CO2 Reduction.

Developing highly efficient bifunctional catalysts for electrocatalysis and photocatalysis suffers from sluggish charge transfer and poor photo-to-electric conversion rate. Herein, micro-sized Cu2O cubes were initially prepared for subsequent transformation into Cu2O@Cu2S core-shell structures by a slight surface sulfurization. The formation of nanostructured Cu2S thin layer at Cu2O surface can endow an immediate charge separation and migration under light irradiation, leading to high surface photovoltages (SPV, 18-30 mV). As a result, the as-prepared Cu2O@Cu2S catalysts exhibited reduced overpotentials (η, only 86 mV is required for the optimized sample to achieve a current density of 10 mA cm-2) for H2 evolution with good cycling stability in electrocatalytic water splitting. Meanwhile, a high methane (CH4) production rate of 30.3 μmol h-1 g-1 can be delivered from the optimized Cu2O@Cu2S sample when used for photocatalytic CO2 reduction. This work has provided a strategy to prepare bifunctional catalysts with improved photoelectric properties for photo/electrocatalytic applications.

GC-MS/HPLC Profiling and Sono-Maceration Mediated Extraction of Osbeckia Parvifolia Polyphenols: In Silico and In Vitro Analysis on Anti-Proliferative Activity in Ovarian Cancer Cell Lines.

Osbeckia parvifolia, an endemic edible plant of Western Ghats, was investigated in the present study for its polyphenolic compounds, including content, constituents, extraction through an ultrasonic-assisted maceration technique and therapeutic potential in biomedical applications. The methanolic extract (OPM) exhibited an IC50 value of 1.25 μg/mL against 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radicals. Furthermore, the ethyl acetate and methanolic extracts also strongly inhibited 5-lipoxygenase, especially OPM (84.93 %), which was comparable to standard curcumin. OPM also elicited cytotoxicity in SKOV3 ovarian cancer cells (93.80 %), surpassing paclitaxel. Bio-accessibility analysis demonstrated that the release of phenolic compounds and antioxidant potential were very high (above 100 %), revealing the possibility of synergistic efficacy of polyphenolic complexes in drug development. Gas Chromatography -Mass Spectrometry (GC-MS) analysis revealed 22 bioactive polyphenolic compounds in OPM, such as epicatechin, quercetin, and psoralidin. This was confirmed by High Performance Liquid Chromatography (HPLC) and High-Pressure Thin Layer Chromatography (HPTLC) analyses, which revealed a high quantity of catechin (37.45 mg/g). Molecular docking revealed the significant binding affinity of these proteins for the ovarian oncoproteins PI3K (-8.52 kcal/mol) and Casp-8 (-8.41 kcal/mol). Adsorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) profiling indicated the favorable pharmacokinetic properties of these compounds, supporting their candidacy in drug formulations against ovarian cancer.

Synthesis and evaluation of vanillin Schiff bases as potential antimicrobial agents against ESBL-producing bacteria: towards novel interventions in antimicrobial stewardship.

The escalating challenge of antimicrobial resistance necessitates the development of novel antibacterial agents. In this study, a series of five vanillin Schiff bases (SB-1 to SB-5) were synthesized from vanillin and various aromatic amines. The chemical structures of these compounds were characterized using Thin Layer Chromatography (TLC), Fourier Transform Infrared Spectroscopy (FT-IR), proton nuclear magnetic resonance ( -NMR), carbon-13 NMR ( -NMR), and mass spectrometry techniques. Antibacterial efficacy was evaluated against strains of bacteria producing extended-spectrum beta-lactamases (ESBL), including Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae using the disc diffusion method. Cytotoxic effects were assessed through haemocompatibility and brine shrimp lethality assays. The Schiff bases demonstrated notable antibacterial activities, with SB-1, SB-2, SB-4, and SB-5 exhibiting zones of inhibition up to 16.0, 16.5, 16.6, and 15.5 mm against ESBL E. coli, respectively. SB-3 showed a maximum inhibition zone of 15.0 mm against ESBL K. pneumoniae. In cytotoxicity assays, the compounds exhibited IC values against red blood cells (RBCs) greater than 200 μg/mL and ranging from 45.7 to 50.5 μg/mL for the brine shrimp assay. While demonstrating potent antibacterial properties, the toxicity towards human RBCs suggests that further toxicity evaluations and structural modifications are essential for developing safer therapeutic agents based on vanillin Schiff bases.

Wind tunnel and flight testing of a lamb wave-based ice accretion sensor

Abstract Severe icing conditions are still a risk in aviation. Heavy ice accretion on aircraft can affect mass and aerodynamic performance in a way, that a catastrophic loss of control may occur. Detecting icing conditions and the extent of ice accretion is therefore essential to react instantly and to assess the severity. This eases the decision to either activate ice protection systems and continue the flight or to leave the icing conditions immediately. These functions can be provided by an icing sensor. Within the EU funded SENS4ICE project, several ice sensors have been developed. One of them is the so-called local ice layer detector (LILD). It uses lamb waves which are guided by the aircraft structure. If an ice accretion happens, the wave guide behavior is affected changing amplitude and lag time of the lamb wave pulses. This can be measured. If the sensor is mounted to a surface on the aircraft which is prone to icing, e.g. the leading edge of the wing, ice can be detected where it is relevant for the aerodynamic performance. Within the project, the sensor hard- and software have been developed to create and measure lamb wave pulses in a wide frequency range. To investigate the influence of ice accretion on the lamb waves, wind tunnel tests were undertaken. Finally, the sensor was investigated in a flight test. In this paper, an overview about the function of the sensor as well as the general signal behavior are given. The results of the wind tunnel test and some preliminary results from the flight tests will be shown. In both tests, the sensor was able to detect even very thin ice layers with minimum delay from the beginning of the ice accretion.

Differentiating Multiple Sclerosis and Glaucoma With Sectoral Pattern Analysis of Peripapillary Nerve Fiber Layer.

To distinguish between multiple sclerosis (MS) and glaucoma by nerve fiber layer (NFL) thinning patterns. MS patients were diagnosed by the 2017 McDonald Criteria; glaucoma patients had disc rim thinning or an NFL defect, with or without perimetric defect. The peripapillary NFL thickness was divided into eight sectors, and percentage reduction (% reduction) was calculated relative to normative reference values. The MS and glaucoma eyes were grouped based on the severity of NFL thinning in the worst sector: significant reduction (<1 percentile of normal reference), borderline reduction (1%∼5%), and no reduction (>5%). We devised four diagnostic indexes, and the area under the curve of receiver operating characteristics (AROC) and accuracy were used to evaluate the indexes. We enrolled 58 control subjects (58 eyes), 56 MS subjects (112 eyes), and 92 glaucoma subjects (92 eyes) at two centers. The most pronounced percent reduction in MS eyes occurred in the temporal-upper and temporal-lower sectors. In glaucoma eyes, this occurred in the inferior-temporal, inferior-nasal, and superior-temporal sectors. The temporal pattern index had the best AROC (0.96, 0.91-1.00) and accuracy (92.6%) in the significant reduction group. It had good AROC (0.88, 0.78-0.99) and accuracy (76.7%) in the borderline reduction group. Normalizing NFL reduction as a percentage of normal reference accentuated patterns characteristic of MS and glaucoma. Quantitative pattern indexes were effective in differentiating the two diseases. The utility of optical coherence tomography in the differential diagnosis of optic neuropathies is enhanced by analyzing the retinal nerve fiber layer percentage reduction pattern.

Partial Selenization Strategy for Fabrication of Ni0.85Se@NiCr-LDH Heterostructure as an Efficient Bifunctional Electrocatalyst for Overall Water Splitting.

NiCr-LDH and its partial selenization as Ni0.85Se@NiCr-LDH heterostructure is established here as an alkaline water electrolyzer for achieving enhanced overall water splitting efficiency. The hydrothermally synthesized optimized batch of Ni0.85Se@NiCr-LDH is thoroughly characterized to elucidate its structure, morphology, and composition. Compared to pristine NiCr-LDH, the batch of Ni0.85Se@NiCr-LDH exhibits exceptional alkaline OER and HER activity with low overpotentials of 258 and 85 mV at 10 mA cm-2, respectively. Besides, Ni0.85Se@NiCr-LDH also exhibits excellent acidic HER with an overpotential of only 61 mV at 10 mA cm-2, indicating that Ni0.85Se@NiCr-LDH can operate effectively across a wide pH range. The excellent electrochemical stability of Ni0.85Se@NiCr-LDH for 24 h operation is attributed to the formation of a thin layer of SeOx during OER operation. The role of selenization and the effect of Cr in the LDH lattice toward enhanced electrocatalytic water splitting is discussed. The outstanding OER and HER performances of Ni0.85Se@NiCr-LDH are attributed to the higher electrochemical active surface area, favorable conditions for adsorption of HER/OER intermediates, low charge transfer resistance, and improved conductivity. The practical application ofNi0.85Se@NiCr-LDHas a bifunctionalelectrocatalyst for overall water splitting is reflected from the low cell voltage of 1.548 V at 10 mA cm-2.

Cold Sintered ZnO-Polystyrene (PS) Composites with Modified Interfacial Structures and Properties.

Lightweight and integrated electronic devices with high performance have become an inevitable trend in the development of power electronic systems. However, it is challenging to obtain lightweight and miniaturized varistors due to the low threshold electric field. Herein, (1 - x)ZnO-xPS composites with a high threshold electric field are prepared through a cold sintering process at 220 °C for 50 min, utilizing lightweight PS to modulate the grain boundary structures of ZnO varistors. With PS content ≤1.5 wt %, the relative densities of cold sintered composites exceed 95%. PS thin layers with a thickness of 2-10 nm are distributed at the grain boundaries of ZnO, forming the Schottky barrier, which triggers nonlinear current-voltage responses. With the addition of PS, the threshold electric field is dramatically enhanced from 135 to 2703 V·mm-1, higher than that of commercial ZnO varistors, which is further demonstrated by the electric field simulation of the Finite Element Method. The interfacial resistance obtained from impedance analysis increases with the increase of the PS content, and the activation energy of (1 - x)ZnO-xPS composites is higher than that of pure ZnO ceramics. This study provides a promising approach for the development of lightweight and cost-effective varistor materials.

Insights into the K–Pg extinction aftermath: The Danish Cerithium Limestone Member

The Cretaceous–Palaeogene (K–Pg) mass extinction about 66 Ma ago was one of Earth's largest mass extinction events. The demise of calcifiers, among others, influenced biogeochemical cycles and changed the conditions for carbonate deposition in the global ocean. This study addresses the sedimentology and carbonate microfacies of the Cerithium Limestone Member of the Rødvig Formation within the renowned Stevns Klint succession in Denmark. The limestone was deposited in the earliest Danian Stage, immediately after the K–Pg mass extinction. It is a pale yellow, partly cemented unit with a dense network of Thalassinoides burrows and numerous flint nodules. Studies of the thin sections revealed that the Cerithium Limestone Member is more variable than expected from its overall homogeneous appearance at the macroscopic scale. The thin sections and scanning electron microscope (SEM) images showed that the highly bioturbated limestone consists of four principal microfacies: a mudstone, a wackestone and two different packstones. The 30 to 120-cm thick Cerithium Limestone Member fills depressions between low-amplitude mounds in the Maastrichtian chalk. The lowermost part constitutes a thin layer of a bryozoan-rich packstone, probably reworked from the crests of the Maastrichtian mounds. The successive part of the member is dominated by wacke stone with mainly foraminifera (planktic and benthic), molluscs and echinoderm debris, and in some areas an abundance of peloids. The foraminifera- and mollusc rich packstone appears in lenses. The mudstone contains few foraminifera and is linked to burrows and syn-sedimentary fractures. SEM observations revealed that the Cerithium Limestone Member corresponds to a dispersed micrite, with small calcite crystals ~1–4 µm in size. The general shape of these calcite crystals suggests precipitation from cyanobacterial activity and, thus, a microbial genesis for the micrite of the Cerithium Limestone Member.

Assessment of Tube–Fin Contact Materials in Heat Exchangers: Guidelines for Simulation and Experiments

This paper describes experiments on finned tube heat exchangers, focusing on reducing the thermal contact resistance at the contact between the pipe and the lamella. Various contact materials, such as solders and adhesives, were investigated. Several methods of establishing contact were tested, including blowtorch soldering, brazing, and furnace soldering. Thermal camera measurements were carried out to assess the performance of the contact materials. Moreover, finite element analysis was performed to evaluate the contact materials and establish guidelines in the fin–tube connection modeling by comparing simplified models with the realistic model. Blowtorch brazing tests were successful while soldering attempts failed. During the thermographic measurements, reflective surfaces could be measured after applying a thin layer of paint with high emissivity. These measurements did not provide valuable results; thus, the contact materials were assessed using a finite element analysis. The results from the finite element analysis showed that all the inspected contact materials provided better heat transfer than not using a contact material. The heat transfer rate of the tight-fit realistic model was found to be 33.65 for air and 34.9 for the Zn-22Al contact material. This finding could be utilized in developing heat exchangers with higher heat transfer with the same size.

Thickness-dependent nanoscale friction across the first-order charge density wave phase transition in 1T-TaS2

The layered charge density wave (CDW) phase transition material 1T-TaS2 has garnered significant attention due to its modulable bandgap and electrical transport properties. These unique properties make 1T-TaS2 highly promising for applications in fields such as optoelectronic devices and microstructure physics devices. In various micro-/nanodevices made from quasi-two-dimensional 1T-TaS2, it is often utilized in thin layers, making the understanding of its frictional properties crucial for practical applications. However, the layer-dependent frictional properties of 1T-TaS2 have not been thoroughly investigated. In this article, we examine the CDW phase transition between the nearly commensurate (NCCDW) and commensurate (CCDW) phases in 1T-TaS2 around 183 K using atomic force microscopy, focusing on the number of layers in the samples. Our results indicate that for thicker samples with more than approximately 17 layers, a friction peak is observed during the NCCDW–CCDW phase transition. In contrast, thinner samples do not exhibit this friction peak, and their friction continuously increases as the temperature decreases. This behavior is attributed to the suppressed NCCDW–CCDW phase transition in thinner samples. These results enhance our understanding of the frictional behavior of 1T-TaS2 in the context of micro-/nano-electromechanical systems. Furthermore, our observations offer a straightforward method to identify the NCCDW–CCDW phase transition, providing an alternative to traditional, more complex techniques such as electrical resistance measurements and Raman spectroscopy.

Membrane piezoelectric MDS-actuator with a flat double spiral of interacting electrodes

A schematic diagram and mathematical model of functioning of a new piezoelectric membrane (MDS) actuator with double spiral (DS) electrodes on the upper and/or lower surfaces of a thin piezoelectric layer with axisymmetric and periodic (with a small period) in radial coordinate mutual reversed electric polarization are presented. The polarization of the layer was realized as a result of connecting the polarizing electric voltage of the appropriate value to the outputs of the double spirals of the electrodes. The electrodes of each (upper and lower) double spiral of the MDS-actuator are made in the form of electrodeposited ribbon coatings on the surfaces of the piezoelectric layer in close proximity to each other (due to the small spiral pitch) to create high values of electric field strength along the lines of force in localized areas of the piezoelectric layer between them when an alternating or constant control electric voltage is connected to the electrodes, in particular, with positive and negative values of the electrical potentials. Importantly, the electric field force lines and, as a consequence, the polarization of the piezoelectric layer of the MDS actuator are oriented mainly along (i.e. towards or against) the radial coordinate of the membrane, in contrast to many conventional actuator schemes. The results of numerical modeling for a circular elastic membrane with piezoelectric actuators installed on its upper and lower surfaces confirmed the effectiveness of the proposed piezoelectric MDS-actuator when it functions according to the “bimorph” scheme, including the use of the proposed new structural element (section) – a piezoelectric “compression ring” MDS at various geometric and control parameters. The effect of a significant increase in the membrane deflection with installed piezoelectric MDS-actuators compared to the use of traditional homogeneous plate piezoelectric actuators of bimorph type for different conditions of the membrane fixation, in particular, stationary (rigid) fixation of its center is revealed. For a hybrid piezoelectric MDS-actuator including independent concentric round and circular (i.e. “compression ring”) sections, the non-monotonic nature and numerical analysis of the nonlinear dependence of the largest deflection at the center of a hinge-immobile membrane fixed at the edge on the ratio of the radii of its round and circular MDS sections were revealed. The cases in which the effect of the “compression ring” is manifested, i.e. when the maximum deflection of a membrane with the “compression ring” exceeds the best possible value of the deflection of this membrane without its use in the traditional “bimorph” scheme, are identified. The new piezoelectric MDS-actuator can be used in micromechanics, controlled optics, sensor technology, acoustics, in particular, in the manufacture of piezoelectric acoustic or sensor elements of membrane type, electromechanical transducers for vibration energy collection.

Characterization and evaluation of a tray dryer with change of position: kinetics and thermodynamic properties of the process, preserving the nutraceutical properties in Golden Delicious apple slices.

The drying kinetics in apple slices between 45–55 °C was studied until reach a moisture ratio of 10±2%. 8 thin layer drying models were statistically fitted where the Midilli-Kucuk model presented the best performance, moreover its drying constant increased with the temperature, effective diffusivity was ranged from 68.16 E-10 – 2.28 E-08 m2 s-1, the Arrhenius factor and activation energy were 3.74 E-02 m2 s-1 and 28.11 kJ mol-1, the enthalpy decreased from 25.46–25.38 kJ mol-1, the entropy was ranged between (-0.2728 – -0.2730) kJ mol-1 K-1, and the Gibbs free energy increased from 112.25–114.98 kJ mol-1. The 45 °C treatment preserved the highest phenolic compounds (51.1±1.54 mg EAG 100 g-1), while the initial activity of elimination of radicals was 766.9±91.4 and 973.3±103.4 µg mg-1 according to the DPPH and ABTS methods, the antioxidant activity shows an inverse behavior to the drying temperature. This work will allow to establish the temperature, time, moisture ratio and energy to drying apple slices according to local weather or under controlled conditions.

Paramagnetic rim lesions are associated with inner retinal layer thinning and progression independent of relapse activity in multiple sclerosis.

Paramagnetic rim lesions (PRLs) are chronic active lesions associated with a severe disease course in multiple sclerosis (MS). This study was undertaken to investigate an association between retinal layer thinning (annualized loss of peripapillary retinal nerve fiber layer [aLpRNFL] and ganglion cell-inner plexiform layer [aLGCIPL]) and PRLs in patients with MS (pwMS). In this study, pwMS with brain magnetic resonance imaging and ≥2 optical coherence tomography scans were included. Cox proportional hazard regression models were performed using progression independent of relapse activity (PIRA) as the dependent variable, and aLpRNFL, aLGCIPL, or the number of PRLs as independent variables, adjusted for covariates. We analyzed data from 97 pwMS (mean age = 35.2 years [SD = 9.9], 71.1% female, median disease duration = 2.3 years [interquartile range = 0.9-9.0]). The number of PRLs was associated with aLpRNFL and aLGCIPL. PIRA was observed in 18 (18.6%) pwMS, with aLpRNFL (hazard ratio [HR] = 1.44 per %/year), aLGCIPL (HR = 1.61 per %/year), and the number of PRLs (HR = 1.24 per PRL) being associated with increased risk of PIRA. The number of PRLs is associated with inner retinal layer thinning and increased risk of PIRA. A combination of PRLs and retinal layer thinning could serve as a surrogate for pwMS at highest risk of disability progression.