Search Results (872)

Background/Objectives: Corneal sensitivity can be decreased by several ocular conditions, including dry eye and refractive surgery, which can lead to ocular epithelial lesions. This decrease can be detected by esthesiometry. The main objective of this study was to evaluate the performance, safety, and efficacy of the Corneal Esthesiometer Brill in healthy subjects without ocular pathologies. Methods: A controlled, randomized, prospective, multicenter pilot clinical study was conducted in adult patients with healthy eyes. Corneal sensitivity measurements were made three times for one eye randomly selected to obtain the corneal sensitivity reference ranges. Additionally, one more measurement was taken after the application of a topical anesthetic. An intra- and inter-observer analysis was performed to assess user dependence, and the last measurement was taken after ocular topical anesthesia to evaluate the device’s sensitivity in detecting corneal sensitivity loss. Results: Ninety-one volunteers were included with a mean age of 25 (SD 3.46, range 18–30), and fifty-eight (63.7%) were female. Corneal sensitivity reference levels ranged from level 2 (3–4 mbar) to level 3 (4–5 mbar). Intra- and inter-observer measurement differences on the same subject without anesthesia were not statistically significant. Corneal pressure before and after local ocular anesthesia had statistically significant differences (p < 0.0001). Conclusions: The Corneal Esthesiometer Brill yielded consistent and reproducible measurements in young volunteers with healthy eyes, enabling objective, observer-independent use and facilitating the detection of significant loss of sensitivity. Full article

Dry topsoil restricts root growth and nutrient uptake in arid regions, thereby significantly reducing crop yield. Hydraulic lift occurs due to the dry topsoil and wet deep soil. This study investigates the effects of topsoil drought intensity (three field capacities in topsoil: 60–70% (W1), 50–60% (W2), and 40–50% (W3)) and nitrogen application rate (N1: 120, N2: 240, and N3: 360 kg ha⁻¹) on cotton quality and the distribution of nitrogen in soil and plant under hydraulic lift using a root-splitting device. The upper pot of the root-splitting device was 22 cm high, with a 26 cm top diameter and a 23 cm bottom diameter; the lower pot of the root-splitting device was 45 cm high, with a 48 cm top diameter and a 36 cm bottom diameter. Topsoil moisture was maintained at W1 without nitrogen application under the control treatment (CK). The W2 and W3 treatments (representing different topsoil drought intensities) were designed to compare the interactive effects of water and nitrogen fertiliser on nitrogen distribution and cotton quality with the CK treatment. Results indicate that the concentrations of nitrate nitrogen (NO₃⁻-N) in the 10–20 cm soil were generally higher than those in the 0–10 cm soil. The topsoil drought intensity and nitrogen application rate had significant impacts on nitrogen concentrations in cotton organs. The W2 treatment produced the maximum nitrogen concentration, except for the root nitrogen concentration in 2021. The nitrogen concentration in the roots and stems peaked at 240 kg ha⁻¹ of nitrogen application rate. The topsoil drought intensity and nitrogen application rate had considerable influences on the cotton dry matter. The nitrogen application rate had a significant impact on the following indexes: internal nitrogen-fertiliser use efficiency (INUE), physiological nitrogen-fertiliser use efficiency (PNUE), and nitrogen-fertiliser recovery efficiency (NRE), except for PNUE in 2020. The INUE of other treatments decreased by 13.82–43.44% compared with CK treatment. In 2021, fibre length and elongation were significantly impacted by the topsoil drought intensity, nitrogen application rates, and their interactions. The nitrogen application rate’s effects on the uniformity index were significant in 2020 and 2021. The hydraulic lift magnitude, NRE, and NO₃⁻-N in the 0–10 cm soil were significantly correlated with each other. There were correlations among cotton quality indexes: fibre length and strength, uniformity index and micronaire, and micronaire and elongation. These findings provide a reference for future research on the mechanism by which hydraulic lift participates in nitrogen distribution in soil and crops and also offer a new direction to utilize deep water to improve the utilization rate of water resources. Full article

Background/Objectives: The use of collagen-based scaffolds in dentition tissue engineering has gained significance and importance in the field as they are structurally equivalent and biologically compatible with the native extracellular matrix (ECM). In this review, collagen-composite scaffolds for pulp, alveolar bone, and periodontal regeneration are analyzed in terms of materials, fabrication techniques, and clinical outcomes. Methods: Recent developments in collagen scaffolds are highlighted in this review, with a focus on type I collagen due to its structural strength and arginine–glycine–aspartic acid (RGD) motifs, which promote cell adhesion and differentiation. Composite materials, freeze-drying, electrospinning, and 3D bioprinting, which are used to improve the functionality of the scaffold, are key developments. Results: This review shows progress in collagen-based scaffolds for restoring dental tissues, such as dentin, gingival tissue, or bone, in humans. Electrospinning and 3D bioprinting are new manufacturing techniques that enhance the functionality of scaffold devices, and incorporating bioactive molecules increases the regenerative capacity; however, stability and long-term efficacy are still problems. Conclusions: Although they have a lot of potential, collagen-composite scaffolds face challenges like rapid degradation and limited mechanical strength. To make long-lasting, tailored dental regeneration therapies feasible, future research needs to improve smart biomaterials, gene delivery, and personalized designs for dental regenerative therapy. Full article

This paper presents the results of wear tests of two types of commercial low-carbon, low-alloy martensitic abrasion-resistant steels, Hardox 450 and XAR 450, which belong to the hardness class 450 HBW. These steels, due to their increased resistance to the abrasive wear mechanism, are used for machine parts for applications in intensive abrasion environments such as construction, mining, and agriculture. The scope of work included microstructure analysis on an optical microscope, chemical composition analysis, Vickers hardness measurements at different loads (HV0.2, HV1 and HV2), and wear testing. Wear tests were carried out by the standard method “dry sand—rubber wheel”, and tests on the Taber abrader device. Microstructure analysis revealed that both steels have a similar non-oriented, homogenous, fine-grained martensitic microstructure. The results of HV2 hardness measurements showed a similar trend for both steels in all examined sections of the plates. For both tested steels, the hardness values of HV0.2 and HV1 are slightly higher than HV2, but the scattering of the results is also greater. Abrasion resistance testing using the standard “dry sand—rubber wheel” method showed that Hardox 450 steel has a lower volume loss of about 8%, but a greater scattering of the results compared to XAR 450 steel. The results of the abrasion resistance test on the Taber abrader device confirmed approximately the same behavior. For both steels, a prediction model was established for a reliable assessment of the wear intensity concerning the grain size. Although examined steels belong to the same hardness class, Hardox steel seems to be a more appropriate choice for the manufacture of machine components exposed to abrasive wear. Full article

Dry powder inhalers (DPIs) are the mainstay in the treatment of obstructive pulmonary diseases. However, the performance of DPI formulations is highly dependent on the used inhaler device and the patient’s inspiratory effort. This study aimed to evaluate and compare the aerosolization behavior of three commercially available capsule-based DPI medications—formoterol (Foradil^®), glycopyrronium (Seebri^® Breezhaler), and tiotropium (Spiriva^®)—delivered using three different capsule-based inhalers (Aerolizer, Breezhaler, and Handihaler), under varying flow conditions. Methods: The aerodynamic performance of each formulation–inhaler combination was assessed using the Next-Generation Impactor (NGI) and Dosage Unit Sampling Apparatus (DUSA) methodology. Fine particle dose (FPD) and aerodynamic particle size distribution (APSD) were determined at fixed flow rates of 15, 30, 60, and 100 L/min, as well as at inhaler-specific flow rates corresponding to a 4 kPa pressure drop. Chromatographic quantification of active ingredients was performed using validated HPLC methods specific to each drug. Results: The FPD values increased consistently with higher flow rates across all tested formulations and inhalers. At a 4 kPa pressure drop, Aerolizer and Breezhaler achieved significantly higher FPDs compared to Handihaler. Notably, in some instances, non-dedicated inhalers produced greater respirable fractions than the originally intended devices. APSD profiles revealed that drug deposition shifted toward smaller NGI stages at higher inspiratory flows, supporting enhanced deep lung delivery potential under optimal conditions. Conclusions: Device resistance, capsule orientation, and piercing mechanics substantially influence drug aerosolization. Although non-dedicated inhalers may offer improved FPDs in vitro, clinical use should adhere to approved drug–device combinations, as these have been validated for efficacy and safety under real-world conditions. Full article

Drilling-induced damage in fiber-reinforced polymer composite materials was measured excavating four laminates, basalt (B₁₄), glass (G₁₄) and their two sandwich type hybrids (B₄G₆B₄, G₄B₆G₄), with 6 mm twist drills at 1520 revolutions per minute and 0.10 mm rev⁻¹ under dry running with an uncoated high-speed steel (HSS-R), grind-coated high-speed steel (HSS-G) or physical vapor deposition-coated (high-speed steel coated with Titanium Nitride (TiN) and Titanium Aluminum Nitride (TiAlN)) drill bits. The hybrid sheets were deliberately incorporated to clarify how alternating basalt–glass architectures redistribute interlaminar stresses during drilling, while the hard, low-friction TiN and TiAlN ceramic coatings enhance cutting performance by forming a heat-resistant tribological barrier that lowers tool–workpiece adhesion, reduces interface temperature, and thereby suppresses thrust-induced delamination. Replacement of an uncoated, grind-coated, high-speed-steel drill (HSS-G) with the latter coats lowered the mechanical and thermal loads substantially: mean thrust fell from 79–94 N to 24–30 N, and peak workpiece temperatures from 112 °C to 74 °C. Accordingly, entry/exit oversize fell from 2.5–4.7% to under 0.6% and, from the surface, the SEM image displayed clean fiber severance rather than pull-out and matrix smear. By analysis of variance (ANOVA), 92.7% of the variance of thrust and 86.6% of that of temperature could be accounted for by the drill-bit factor, thus confirming that the coatings overwhelm the laminate structure and hybrid stacking simply redistribute, but cannot overcome, the former influence. Regression models and an artificial neural network optimized via meta-heuristic optimization foretold thrust, temperature and delamination with an R² value of 0.94 or higher, providing an instant-screening device with which to explore industrial application. The work reveals TiAlN- and TiN-coated drills as financially competitive alternatives with which to achieve ±1% dimensional accuracy and minimum subsurface damage during multi-material composite machining. Full article

Human cognitive performance is influenced by external factors, including indoor environmental quality (IEQ). Understanding how these factors affect stress, attention, and relaxation is essential in environments such as workplaces and educational institutions, where cognitive function directly impacts performance. This study examines the effects of IEQ on students’ attention and relaxation levels during various lecture periods, focusing on design major students. Three key IEQ parameters (air temperature, relative humidity, and natural lighting) were evaluated for their effects on cognitive states using electroencephalogram (EEG) measurements in a controlled setting. Participants wore non-invasive, portable EEG devices to monitor neurophysiological activity across two sessions, each involving four scenarios: (i) baseline, (ii) increased natural light exposure, (iii) elevated relative humidity, and (iv) increased air temperature. EEG-derived metrics of attention and relaxation were analyzed alongside environmental data, including temperature, humidity, lighting conditions, carbon dioxide (CO₂) concentration, total volatile organic compounds (TVOC), and particulate matter (PM), to identify potential correlations. Results showed that natural light exposure improved relaxation but reduced attention, suggesting a restorative effect on stress that may also introduce distractions. Attention peaked under moderately warm, dry conditions (25–26 °C and 16–19% relative humidity), correlating positively with temperature (Pearson correlation coefficient, $r$ = 0.32) and negatively with humidity ($r$ = −0.50). Conversely, relaxation was highest under cooler, more humid conditions (23–24 °C and 24–26% relative humidity). Attention was negatively correlated with CO₂ ($r$ = −0.47) and PM_2.5 ($r$ = −0.46), suggesting that poor air quality impairs alertness. Relaxation showed weaker but positive correlations with PM_2.5 ($r$ = 0.38), PM_1.0 ($r$ = 0.35), and CO₂ ($r$ = 0.32). Ultrafine particles (PM_0.3, PM_0.5) and TVOC had minimal association with cognitive states. Overall, this study underscores the importance of optimizing indoor environments in educational settings to enhance academic performance and supports the development of evidence-based design standards to foster healthy, effective learning environments. Full article

To address the problems of the time consumption, labor intensiveness, easy contamination, uneven drying, and impact on the medicinal efficacy of Fritillaria ussuriensis in the traditional drying method, the hot-air-drying characteristics of Fritillaria ussuriensis were studied. The changes in the moisture ratio and drying rate of Fritillaria ussuriensis under different hot-air-drying conditions (45 °C, 55 °C, 65 °C) were compared and analyzed. Six common mathematical models were used to fit the moisture change law, and it was found that the cubic model was the most suitable for describing the drying characteristics of Fritillaria ussuriensis. The R² values after fitting under the three temperature conditions were all greater than 0.99, and the maximum was achieved at 45 °C. Based on the principle of hot-air drying, a drying device for Fritillaria ussuriensis with a processing capacity of 15 kg/h was designed. It adopted a thermal circulation structure of inner and outer drying ovens, with the heating chamber separated from the drying chamber. The structural parameters were optimized based on Fluent simulation analysis. After optimization, the temperature of each layer was stable at 338 K ± 2 K, and the pressure field and velocity field were evenly distributed. The drying process parameters of Fritillaria ussuriensis were optimized based on response surface analysis, and the optimal process parameters were obtained as follows: inlet temperature: 338 K (65 °C), inlet air velocity: 3 m/s, and drying time: 10 h. The simulation results showed that the predicted moisture content of Fritillaria ussuriensis under the optimal working conditions was 12.58%, the temperature difference of Fritillaria ussuriensis at different positions was within 0.8 °C, and the humidity deviation was about 1%. A prototype of the drying device was built, and the drying test of Fritillaria ussuriensis was carried out. It was found that the temperature and moisture content of Fritillaria ussuriensis were consistent with the simulation results and met the design requirements, verifying the rationality of the device structure and the reliability of the simulation model. This design can significantly improve the distribution of the internal flow field and temperature field of the drying device, improve the drying quality and production efficiency of Fritillaria ussuriensis, and provide a technical reference for the Chinese herbal medicine-drying industry. Full article

To enhance agricultural soil health and soil organic carbon (SOC) sequestration, it is important to accurately measure SOC. The aim of this study was to compare common methods for measuring SOC in soils in order to determine the most effective approach among different agricultural land types. The measurement methods of loss-on-ignition (LOI), automated dry combustion (Dumas), and real-time near-infrared spectroscopy (NIRS) were compared. A total of 95 soil core samples, ranging in clay and calcareous content, were collected across a range of agricultural land types from forty-eight fields across five farms in the Southwest of England. There were similar and positive correlations between all three methods for measuring SOC (ranging from r = 0.549 to 0.579; all p < 0.001). On average, permanent grass fields had higher SOC content (6.6%) than arable and temporary ley fields (4.6% and 4.5%, respectively), with the difference of 2% indicating a higher carbon storage potential in permanent grassland fields. Newly predicted conversion equations of linear regression were developed among the three measurement methods according to all the fields and land types. The correlation of the conversation equations among the three methods in permanent grass fields was strong and significant compared to those in both arable and temporary ley fields. The analysed results could help understand soil carbon management and maximise sequestration. Moreover, the approach of using real-time NIRS analysis with a rechargeable portable NIRS soil device can offer a convenient and cost-saving alternative for monitoring preliminary SOC changes timely on or offsite without personnel risks from the high-temperature furnace and chemical reagent adopted in the LOI and Dumas processes, respectively, at the laboratory. Therefore, the study suggests that faster, lower-cost, and safer methods like NIRS for analysing initial SOC measurements are now available to provide similar SOC results as traditional soil analysis methods of the LOI and Dumas. Further studies on assessing SOC levels in different farm locations, land, and soil types across seasons using NIRS will improve benchmarked SOC data for farm stakeholders in making evidence-informed agricultural practices. Full article

Devices that meet the needs of agricultural biogas plants represent a significant share of the energy balance of the source. The digester mixer is a crucial component installed in the fermentation chamber. Energy consumption during mixing depends on the regime and intensity, as well as the rheological properties of the carrier liquid, the dry matter content, and the dimensions of the fibers. Bioreactor operators often oversize mixers and extend mixing duration to avoid disruptions in biogas production. This paper analyzed the influence of digester mixer operations on selected electrical power quality parameters. For this purpose, two agricultural biogas plants with a capacity of 40 kW, connected to the low-voltage grid, were studied (one located approximately 120 m from the transformer station and the second 430 m away). As shown by the correlations presented in the article, the connection point of the biogas plant significantly impacted the magnitude of the influence of mixer operations on the analyzed voltage parameters. In the second biogas plant, switching on the mixers (in the absence of generation) caused the grid voltage to drop to the lower value permitted by regulations. (Switching on the mixers caused a change in voltage by about 30 V.) The most disturbances were introduced into the grid when the power generated by the biogas plant was equal to the power consumed by its internal equipment. (THD_I then reached as high as 63.2%, while in other cases, it did not exceed 17%.) Furthermore, the operation of the mixers alone resulted in a reduction of approximately 1 MWh of energy exported to the power grid per month. Full article

Background: Electroencephalography (EEG) systems based on textile electrodes are increasingly being developed to address the need for more wearable sensor systems for brain function monitoring. Blink-related oscillations (BROs) are a new measure of brain function that corresponds to brainwave responses occurring after spontaneous blinking, and indexes neural processes as the brain evaluates new visual information appearing after eye re-opening. Prior studies have reported BRO utility as both a clinical and non-clinical biomarker of cognition, but no study has demonstrated BRO measurement using textile-based EEG devices that facilitate user comfort for real-world applications. Methods: We investigated BRO measurement using a four-channel EEG system with textile electrodes by extracting BRO responses using existing, publicly available EEG data (n = 9). We compared BRO effects derived from textile-based electrodes with those from standard dry Ag/Ag-Cl electrodes collected at the same locations (i.e., Fp1, Fp2, F7, F8) and using the same EEG amplifier. Results: Results showed that BRO effects measured using textile electrodes exhibited similar features in both time and frequency domains compared to dry Ag/Ag-Cl electrodes. Data from both technologies also showed similar performance in artifact removal and signal capture. Conclusions: These findings provide the first demonstration of successful BRO signal capture using four-channel EEG with textile electrodes, providing compelling evidence toward the development of a comfortable and user-friendly EEG technology that uses the simple activity of blinking for objective brain function assessment in a variety of settings. Full article

Expansive soils, characterized by the presence of surface and subsurface cracks, over-consolidation, and swell-shrink properties, present significant challenges to slope stability in geotechnical engineering. Despite extensive research, preventing geohazards associated with expansive soils remains unresolved. This study investigates shallow sliding failures in slopes of highly expansive soils induced by rainfall, using model tests to explore deformation and mechanical behavior under cyclic wetting and drying conditions, focusing on the interaction between soil properties and environmental factors. Model tests were conducted in a wedge-shaped box filled with Nanyang expansive clay from Henan, China, which is classified as high-plasticity clay (CH) according to the Unified Soil Classification System (USCS). The soil was compacted in four layers to maintain a 1:2 slope ratio (i.e., 1 vertical to 2 horizontal), which reflects typical expansive soil slope configurations observed in the field. Monitoring devices, including moisture sensors, pressure transducers, and displacement sensors, recorded changes in soil moisture, stress, and deformation. A static treatment phase allowed natural crack development to simulate real-world conditions. Key findings revealed that shear failure propagated along pre-existing cracks and weak structural discontinuities, supporting the progressive failure theory in shallow sliding. Cracks significantly influenced water infiltration, creating localized stress concentrations and deformation. Atmospheric conditions and wet-dry cycles were crucial, as increased moisture content reduced soil suction and weakened the slope’s strength. These results enhance understanding of expansive soil slope failure mechanisms and provide a theoretical foundation for developing improved stabilization techniques. Full article

Recent advancements in polymer science have catalyzed a transformative shift in biomedical engineering, particularly through the development of biodegradable and smart polymers. This review explores the evolution, functionality, and application of these materials in areas such as tissue scaffolding, cardiovascular occluders, and controlled drug delivery systems. Emphasis is placed on shape-memory polymers (SMPs), conductive polymers, and polymer-based composites that combine tunable degradation, mechanical strength, and bioactivity. The synergy between natural and synthetic polymers—augmented by nanotechnology and additive manufacturing—enables the creation of intelligent scaffolds and implantable devices tailored for specific clinical needs. Key fabrication methods, including electrospinning, freeze-drying, and emulsion-based techniques, are discussed in relation to pore structure and functionalization strategies. Finally, the review highlights emerging trends, including ionic doping, 3D printing, and multifunctional nanocarriers, outlining their roles in the future of regenerative medicine and personalized therapeutics. Full article

Numerous scientific studies have confirmed the effectiveness of seed bioactivation using electromagnetic fields (EMFs) in agriculture. This article presents the results of the remote application of an EMF TOR device in the cultivation of barley Hordeum vulgare L. Laboratory studies and field tests were conducted, showing a positive effect on the growth and development of plants both when treating dry seeds before sowing and when treating sown seeds in the field. The optimal time period for EMF treatment was determined: treating air-dried seeds with EMFs before sowing for 10–15 min increased germination by 5–18% and the growth rate of seedlings by 2–3 times. The maximum observed effect occurred during the treatment period from 7:00 to 11:00. As a result of changing the balance of phytohormones, the further stimulation of the root system and the assimilation surface of plants was noted due to a 1.5-fold increase in the content of auxins. The density of productive stems, ear length, seed set, and 1000 seed weight increased, which ultimately led to an increase in yield by more than 10% and, in some varieties, to a decrease in the protein content in grains compared to the control variant (by 3–22%), bringing them closer to brewing conditions. Full article

Two-dimensional (2D) materials have been proposed for use in a multitude of applications, with graphene being one of the most well-known 2D materials. Despite their potential to contribute to innovative solutions, the fabrication of such devices still faces significant challenges. One of the key challenges is the fabrication at a wafer-level scale, a fundamental step for allowing reliable and reproducible fabrication of a large volume of devices with predictable properties. Overcoming this barrier will allow further integration with sensors and actuators, as well as enabling the fabrication of complex circuits based on 2D materials. This work presents the fabrication steps for a process that allows the on-wafer fabrication of active and passive radiofrequency (RF) devices enabled by graphene. Two fabrication processes are presented. In the first one, graphene is transferred to a back gate surface using critical point drying to prevent cracks in the graphene. In the second process, graphene is transferred to a flat surface planarized by ion milling, with the gate being buried beneath the graphene. The fabrication employs a damascene-like process, ensuring a flat surface that preserves the graphene lattice. RF transistors, passive RF components, and antennas designed for backscatter applications are fabricated and measured, illustrating the versatility and potential of the proposed method for 2D material-based RF devices. The integration of graphene on devices is also demonstrated in an antenna. This aimed to demonstrate that graphene can also be used as a passive device. Through this device, it is possible to measure different backscatter responses according to the applied graphene gating voltage, demonstrating the possibility of wireless sensor development. With the proposed fabrication processes, a flat graphene with good quality is achieved, leading to the fabrication of RF active devices (graphene transistors) with intrinsic f_T and f_max of 14 GHz and 80 GHz, respectively. Excellent yield and reproducibility are achieved through these methods. Furthermore, since the graphene membranes are grown by Chemical Vapor Deposition (CVD), it is expected that this process can also be applied to other 2D materials. Full article