Thickness Loss Research Articles

From Burst to Sustained Release: The Effect of Antibiotic Structure Incorporated into Chitosan-Based Films

Background/Objectives: Medical devices are susceptible to bacterial colonization and biofilm formation, which can result in severe infections, leading to prolonged hospital stays and increased burden on society. Antibacterial films have the potential to assist in preventing biofilm formation, thereby reducing administration of antibiotics and the emergence of antibiotic-resistant strains. In a previous study, a chitosan-based matrix crosslinked with tannic acid and loaded with gentamicin was reported. In this study, five different antibiotics (moxifloxacin, ciprofloxacin, trimethoprim, sulfamethoxazole or linezolid) were loaded into these chitosan-based films, and their impact on the release behavior carefully assessed. Methods: The samples were characterized according to their thickness, swelling, and mass loss in phosphate-buffered saline (PBS), as well as by morphology using scanning electron microscopy (SEM) and optical phase contrast microscopy. Antibiotic release over time was quantified in PBS by high-performance liquid chromatography (HPLC). Antibacterial activity was investigated by disk diffusion test and antibiotic release over time. Finally, the cytotoxicity of the samples was assessed with human dermal fibroblasts. Results: The obtained results differed significantly, especially regarding the antibiotic release time and antibacterial activity, which varied from one day to six months, enabling classification of the films from burst/transient to prolonged release. The films also showed antibacterial features against bacteria mostly present in medical devices and displayed to be non-cytotoxic. Conclusions: In conclusion, it was demonstrated that the antibiotics structure significantly alters the release kinetics, and that by carefully selecting the antibiotic, the consequent release can be tuned. This approach yielded films that could be used for potentially-scalable release in antimicrobial coatings specific to medical devices, aiming to reduce biomaterial associated infections (BAIs).

Exploring the impact of aminoethoxyvinylglycine (AVG) on the ripening behaviour and quality of bananas under different storage conditions

ABSTRACT Bananas rapidly undergo physiological deterioration after harvest owing to their climacteric and perishable nature causing significant economic yield loss. Thus, the adoption of postharvest loss mitigation strategies becomes imperative for enhancing fruit longevity. This study aimed to assess the effect of postharvest treatment with different concentrations of aminoethoxyvinylglycine (AVG) on shelf life extension and quality sustainability of bananas, such as Grand Naine, Poovan and Ney Poovan, kept under ambient (27°C ± 2°C) and cool (17°C) conditions. The findings revealed that AVG-treated bananas reduced weight loss of banana hands (0.655–2.559 kg hand−1) and higher peel thickness (0.86–2.73 mm) and firmness (6.54–12.01 N) over untreated control at ambient storage condition, whereas under cool storage, weight loss of banana hands reduced from 0.761 to 2.579 kg hand−1, while both peel thickness (1.24–2.84 mm) and firmness (7.75–11.45 N) were retained for varieties. The physio-chemical traits of fruit, such as total chlorophyll and starch content, were improved due to AVG treatment under both storage conditions. Among the treatments, postharvest application of AVG at 700 ppm showed better performance in the morphological, physiological and quality characters irrespective of the varieties.

Theoretical analysis of the piston ring-pack for predicting friction and power loss in an internal combustion engine

The piston ring is considered an essential element in the operation of the internal combustion engine to improve its efficiency and reduce its emissions. It is resistant to high temperature and high-pressure gases in the combustion chamber. A one-dimensional analysis method of lubrication between piston rings and cylinder liner in mixed lubrication conditions is developed in this article by using the GT-Suite simulation software. We applied the finite difference numerical method to solve the Reynolds equation to obtain the variation during an engine cycle of the following parameters; film thickness, frictional force, and power loss. The solution results presented can be used to improve the design of the piston ring pack in internal combustion engines and is available for industry usage.

A Novel Technique in Determining Mud Cake Permeability in SiO2 Nanoparticles and KCl Salt Water Based Drilling Fluid using Deep Learning Algorithm

The permeability of the mud cake formed at the formation-wellbore interface is an important factor in the designing of water-based drilling fluids. This study presents a novel approach to utilizing experimental thixotropic and rheological parameters of polymeric water-based drilling fluids having varying concentrations of SiO2 nanoparticles and KCl salt. A fully connected feed-forward multi-layered neural network, more commonly known as a Multilayer Perceptron (MLP) was developed to predict the mud cake permeability using input parameters such as SiO2 & KCl concentration, differential pressure, temperature, mud cake thickness, API LPLT and HPHT filter loss volume and spurt loss volume. The results suggested that the developed Multilayer Perceptron model effectively determined the mud cake permeability based on the input parameters of the WBDF mentioned above. The model converged on the global minima, minimizing the loss function using the Gradient descent algorithm. A higher Coefficient of Determination (R2) value i.e., 0.8781, and a lesser Root Mean Square Error (RMSE) value i.e., 0.04378 indicates the higher accuracy of the model. Pearson’s Coefficient of Correlation obtained via the heatmap indicates that mud cake permeability is strongly influenced by the differential pressure followed by filter loss volume, spurt loss volume, mud cake thickness, and temperature. Previous similar studies have focused on using machine learning algorithms, this study utilized a robust deep learning algorithm i.e., Multilayer Perceptron (MLP) neural network to simultaneously model the combined effects of SiO2 nanoparticles and KCl salt concentrations on mud cake permeability, offering an unprecedented level of accuracy in predicting key WBDF performance parameters

Monitoring of several morphometric parameters of the optic nerve and retina in persons without glaucoma and patients with primary open-angle glaucoma using various types of spectacle correction

Purpose: to perform long-term monitoring of the state of several morphometric parameters of the retina and optic nerve in persons without glaucoma and patients with primary open-angle glaucoma (POAG) in the conditions of achieving tolerant and target IOP against the background of the use of various types of spectacle correction. Material and methods: 139 patients aged 40–60 years with various types of clinical refraction were examined, 41 subjects (81 eyes) of them were without glaucoma, 98 patients (164 eyes) had POAG at stage I–II. In addition to standard methods, the scope of the examination included optical coherence tomography (OCT) of the optic nerve and the central area of the retina to determine the thickness of the retinal nerve fiber layer (RNFL), retinal ganglion cell complex (RGCC) and the area of the neuroretinal rim (NRR). The study was conducted in 4 observation groups. The first (21subjects) and the second (20 subjects) groups were represented by persons without glaucoma who used monofocal spectacle correction and progressive spectacle correction for near work, respectively. The third (50 subjects) and the fourth (48 subjects) groups were composed of patients with POAG who also used, respectively, monofocal spectacle correction for near vision or progressive spectacle correction against the background of topical hypotensive therapy with the achievement of tolerant and target IOP. The follow-up period was three years. Results: There were no significant changes in the area of NRR (p 0,5) and in the thickness of RNFL (p 0,2) and RGCC (p 0,3) over the three-year follow-up period in all patients without glaucoma. In patients with POAG who applied progressive correction, no negative dynamics was revealed in the NRR area (p 0,5) and in the thickness of RNFL (p 0,5) and RGCC (p 0,5) during the follow-up period. POAG patients with using monofocal correction had noticeable losses in RNFL and RGCC thickness (p 0,05) without a significant decrease in the area of NRR (p 0,3). Conclusion: The progressive spectacle correction using provides accommodative regulation of IOP in POAG and implements an indirect neuroprotective effect.

Functional Magnetic Neuromuscular Stimulation vs. Routine Physiotherapy in the Critically Ill for Prevention of ICU Acquired Muscle Loss: A Randomised Controlled Trial

Background and Objectives: Muscle loss is a known complication of ICU admission. The aim of the study was to investigate the effect of neuromuscular functional magnetic stimulation (FMS) on quadriceps muscle thickness in critically ill patients. Materials and Methods: Among ICU patients one quadriceps was randomized to FMS (Tesla Stym,Iskra Medical, Ljubljana, Slovenia) stimulation and the other to control care. Quadriceps thickness was measured by ultrasound (US) in transversal and longitudinal planes at enrolment, Days 3–5, and Days 9–12. The trial stopped early following an interim analysis comparing muscle thickness differences between groups using repeated measures ANOVA. Results: Of 18 patients randomized, 2 died before completing the trial. The final analysis reported included 16 patients (female 38%, age 68 ± 10 years, SOFA 10.8 ± 2.7). Three mild skin thermal injuries were noted initially, which were later avoided with proper positioning of FMS probe. Primary outcome comparison showed that quadriceps thickness in transversal and longitudinal planes decreased in the non-stimulated legs and, but it did not change in FMS legs (−4.1 mm (95%CI: −9.4 to −0.6) vs. −0.7 mm (95%CI: −4.1 to −0.7) (p = 0.03) and −4.4 mm (95%CI: −8.9 to −1.1) vs. −1.5 mm (95%CI: −2.6 to −2.2) (p = 0.02), respectively) (ANOVA difference between groups p = 0.036 and 0.01, respectively). Conclusions: In the critically ill, neuromuscular FMS is feasible and safe with precautions applied to avoid possible skin thermal injury. FMS decreases the loss of quadriceps muscle thickness.

Glacial lake outburst flood risk assessment of a rapidly expanding glacial lake in the Ladakh region of Western Himalaya, using hydrodynamic modeling

The ongoing trend of warming climate has made Glacial Lake Outburst Floods (GLOFs) a major cryospheric hazard worldwide, especially in the Himalayas. GLOFs in the Himalayan region are mostly caused by moraine-dammed proglacial lakes and ice-dammed lakes. These sporadic disasters have resulted in significant loss of life and property. This study offers a comprehensive analysis of the GLOF hazard potential of a potentially dangerous proglacial lake (PDGL) in the Ladakh region. This research explores the GLOF threat from the lake using multi-criteria analysis and advanced 2D hydrodynamic modeling approaches. The mass balance response of the mother glacier, its flow dynamics, and glacier-lake interactions were examined for the past 22 years. The findings show that over this period, the PDGL has had a notable expansion of 78.7%, accompanied by a significant recession of 13.2% in its feeding glacier. The glacier has witnessed an average thickness loss of ⁓7 m at the rate of 0.32 m a−1 during this period. The average, lowest, and maximum depth of the glacier were found to be 30.95, 14.30, and 50.57 m, respectively and the average velocity of the glacier was estimated as 3.38 m a−1. Because of the lake’s rapid expansion and steep surrounding slopes, it was classified as a high-hazard lake. The risk to the downstream community was assessed through 2D hydrodynamic modeling using the HEC-RAS tool. The maximum discharge under the worst-case scenario for the piping and overtopping failures was estimated as 3890.99 m3s−1 and 5111.39 m3s−1, respectively. The area potentially under the threat of inundation was calculated to be 4.74 and 5.38 km2 for the moderate and worst-case scenarios respectively. The expected maximum flood velocities range from 18.26 to 23.78 meters, respectively for the moderate and worst-case scenarios. At several locations in the downstream area, routed hydrographs representing the GLOF propagation were generated. The findings show that the flood wave in the worst-case scenario would arrive at the first settlement in 50 min, with a peak velocity of 12.36 m s−1. The potentially inundated area includes critical infrastructure such as bridges, residential houses, and roads. To mitigate the potential risk associated with this lake, a more detailed and on-site study is highly recommended.

Research on mechanical property degradation model of equipment compartment floor under atmospheric corrosion condition

A mechanical property degradation model of material fatigue life varying with stress level and corrosion time was developed in this study. An acidified NaCl solution was used to accelerate the corrosion of stainless-steel samples, and the relationship between laboratory-accelerated corrosion and atmospheric corrosion was established using corrosion thickness loss parameters. Based on the results of a pre-corroded fatigue test, lgN–S–T surface models and a modified version of Miner’s rule for calculating nonlinear mechanical damage accumulation were proposed. Taking a real part of a high-speed train as an example, critical operating mileages considering material fatigue performance degradation under corrosion conditions were calculated, which were consistent with failure mileages of the census results.

Comparison and mechanism study on solidification of loose pisha sandstone by indigenous bacteria and sporosarcina pasteurii

Pisha sandstone is a kind of sandstone which is easy to collapse by water in Shanxi, Shaanxi and Inner Mongolia of China, and suffers from hydraulic erosion all the year round. In recent years, some scholars have used microbial induced calcium carbonate precipitation (MICP) technology to solidify Pisha sandstone to improve the water erosion resistance of Pisha sandstone. However, for the climate environment with low average temperature in Pisha sandstone area, the commonly used Sporosarcina pasteurii are not well adapted. The purpose of this study is to use the indigenous strainsto solidify the loose Pisha sandstone, and to compare the growth adaptability, mechanical properties and water erosion resistance of the solidified layer with Sarcina pasteurii at different temperatures, and to explore the mechanism of different temperatures and strains affecting the microbial solidification of Pisha sandstone from the micro scale. At the same time, a mixed bacterial liquid solidification test was also set up. The results showed that the solidified thickness of indigenous strains was 4.65 % higher than that of Sporosarcina pasteurii, and the thickness and strength of mixed strains were increased by 19.57 % and 36.62 %, respectively. The growth and solidification effect of indigenous strains were less affected by low temperature. Compared with Sporosarcina pasteurii, at low temperature, the bacterial concentration decrease of indigenous strains was reduced by 26.13 %, the thickness loss of solidified layer was reduced by 13.04 %, and the strength loss of solidified layer was reduced by 13.39 %. The effect of low temperature on the growth of bacteria is mainly reflected in affecting the maximum concentration of bacteria and the growth rate. The effect on MICP mainly reflected in affecting the life activities of bacteria and the crystal form and morphology of calcium carbonate. The research results provide a theoretical basis for the MICP technology application of indigenous strains and multi-strains in Pisha sandstone area soil reinforcement and solidification slope.

Corrosion resistance analysis of Al2O3-TiO2 composite ceramic coatings on carbon steel pipe surfaces

This study investigates the corrosion resistance of Al2O3-TiO2 composite coatings reinforced with multi-walled carbon nanotubes (MWCNTs) on carbon steel pipe surfaces. Coatings were deposited using atmospheric plasma spraying (APS) and high velocity oxy-fuel (HVOF) techniques. Microstructural analysis revealed that HVOF-sprayed coatings exhibited denser and more homogeneous structures compared to APS-sprayed coatings. Electrochemical tests in 3.5 wt% NaCl solution showed that the HVOF-sprayed Al2O3-13 wt% TiO2-1.5 wt% MWCNT coating demonstrated the lowest corrosion current density of 7.6 × 10−9 A/cm2 and the most positive corrosion potential. Hot corrosion tests in a simulated boiler environment (500°C, 1000 h) revealed that this coating also exhibited minimal weight gain (0.9 mg/cm2) and thickness loss (2 μm). The corrosion rate of the optimal coating was 0.05 mm/year, significantly lower than the bare carbon steel (2.45 mm/year). XRD analysis of corroded samples showed that HVOF-sprayed coatings maintained their original phase composition without detectable substrate corrosion products. The superior corrosion resistance of the HVOF-sprayed Al2O3-13 wt% TiO2-1.5 wt% MWCNT coating is attributed to its optimized composition, dense microstructure, and the reinforcing effect of MWCNTs. These findings provide valuable insights for developing advanced coating solutions to mitigate corrosion-related challenges in the oil and gas industry and other harsh industrial environments.

Maternal loss of 24-hydroxylase causes increased intestinal calcium absorption and hypercalcemia during pregnancy but reduced skeletal resorption during lactation in mice.

Inactivation of 24-hydroxylase (CYP24A1) causes mild hypercalcemia in humans that becomes severe and life-threatening during pregnancy through unclear mechanisms. We studied Cyp24a1 null mice during pregnancy, lactation, and post-weaning. We hypothesized that Cyp24a1 nulls have a much greater increase in calcitriol during pregnancy and lactation, leading to markedly increased intestinal calcium absorption and reduced lactational bone loss. WT and Cyp24a1 null sisters were mated to Cyp24a1+/- males. Timepoints included baseline (BL), late pregnancy (LP), mid-lactation (ML), late lactation (LL), and weekly x4 weeks of post-weaning recovery (R1-4). Assessments included intestinal calcium absorption (IntCaAbs) by gavage of 45Ca, bone mineral content (BMC) by DXA, microCT of femurs, 3-point bending tests of tibias, serum hormones, serum and urine minerals, milk analysis, and intestinal gene expression. At LP, whole body BMC increased equally by ~12% in null and WT. Calcitriol was 2.5-fold higher in nulls vs WT, accompanied by 3-fold increased IntCaAbs, hypercalcemia, hypercalciuria, and 6.5-fold higher FGF23. PTH was suppressed in both. Twenty percent of null dams died during delivery but their serum calcium at LP did not differ from Cyp24a1 nulls that survived. At ML, calcitriol, IntCaAbs, and FGF23 declined in both genotypes but remained higher than BL values in Cyp24a1 nulls. By LL, nulls were still hypercalcemic vs WT, and had lost less mean whole body BMC (11% vs. 21%, P<.02), but by micro-CT there were no differences from WT in cortical or trabecular bone mass. Lactational losses in BMC, cortical thickness, and trabecular number were restored by R4 in both genotypes. In summary, ablation of Cyp24a1 increased IntCaAbs and caused hypercalcemia during pregnancy and lactation, late gestational mortality in some nulls, and reduced lactational BMC loss. Treating women with gestational hypercalcemia from CYP24A1 mutations should focus on reducing calcitriol or IntCaAbs, since increased bone resorption is not the cause.

Unlocking the potentials using humidifier-dehumidifier for proton exchange membrane fuel cell waste heat recovery

This study addresses the dual challenges of waste heat dissipation and operational longevity degradation in proton exchange membrane fuel cells (PEMFCs) by proposing a novel hybrid system that integrates PEMFC with a humidifier-dehumidifier (HDH) unit. The primary objective is to enhance the energy efficiency and sustainability of PEMFC systems by leveraging waste heat for freshwater generation. A comprehensive mathematical model based on thermodynamic and electrochemical principles is developed to capture the system’s inherent irreversible losses. The performance metrics, including power density, energy efficiency, and exergy efficiency, are evaluated through systematic computational simulations. The proposed PEMFC/HDH hybrid system achieves a maximum power density of 4.8292 W cm-2 and an energy efficiency of 17.30%, showing a 1.48% improvement over standalone PEMFC systems. Parametric studies reveal that optimizing operating pressure significantly enhances system performance, while factors such as increased PEM thickness and thermodynamic loss composite parameter hinder it. Local sensitivity analysis identifies PEM thickness as the most critical parameter affecting performance. This research pioneers the integration of PEMFC and HDH for cogeneration, offering a viable path for performance enhancement and efficient waste heat utilization. The findings contribute to the strategic design and operational regulation of PEMFC-based hybrid systems for sustainable energy solutions.

Durability improvement of electrochromic WO3 thin films by deposition of an ultra-thin Al2O3 layer via atomic layer deposition

Introduction of an ultra-thin Al2O3 protective layer via atomic layer deposition (ALD) significantly enhances the durability and performance of amorphous tungsten trioxide (a-WO3) thin films for electrochromic devices. The Al2O3 layer, despite being less than 4 nm thick, effectively suppresses the dissolution of WO3 that typically occurs through hydration reactions forming WO3·H2O and tungstic acid (H2WO4). XRD and XPS analyses confirmed the presence of Al2O3 and its minimal impact on the amorphous structure of WO3 thin films. Optical transmittance measurements showed that the Al2O3-protected a-WO3 thin films maintained a higher transmittance modulation (ΔT) compared to bare a-WO3 thin films, with the ALD30 sample retaining 87.9 % of its initial transmittance modulation after 1000 cycles, in contrast to the rapid degradation observed in unprotected films. Microstructural analysis revealed significantly fewer surface cracks and reduced thickness loss in Al2O3-coated films after 100 cycles. Additionally, ICP-MS analysis indicated a much lower W concentration in the electrolyte for Al2O3-protected samples, confirming reduced dissolution.

Karakteristik Sensori dan Fisikokimia Kukis dari Campuran Tepung Mocaf dan Tepung Kulit Buah Naga

To support the goal of zero waste outlined in the sustainable development goals (SDGs), repurposing dragon fruit peel waste presents a promising opportunity. In Indonesia, the high demand for dragon fruit leads to the generation of considerable organic waste. This study explored the use of dragon fruit peel flour, combined with modified cassava (mocaf) flour, as a wheat flour alternative to improve the sensory and chemical properties of gluten-free cookies. The research involved preparing the flours and cookies, followed by conducting sensory, physical, and chemical analyses. A completely randomized design (CRD) was employed, testing five formulations with varying ratios of mocaf flour to dragon fruit peel flour. The results indicated that 73% of panelists preferred the crispiness of cookies containing 25% dragon fruit peel flour, while 60% were satisfied with the color of cookies containing 45% dragon fruit peel flour. Physical analysis showed no significant differences in thickness or bake loss, but there were notable differences in diameter, spread ratio, and color. As the proportion of dragon fruit peel flour increased, the cookies showed significant improvements in chemical characteristics, including higher levels of moisture, ash, fat, protein, and fiber content. Additionally, the content of total phenolics and antioxidant activity increased with higher ratios of dragon fruit peel flour, reaching 1.14 mg GAE/g for total phenolics and 662.64 mg AAE/g for antioxidant activity. FTIR analysis revealed a consistent absorbance pattern across samples, with minor variations in peak intensities at specific wavenumbers. Based on the sensory, physical, and chemical evaluations, cookies containing 45% dragon fruit peel flour were recommended for production.

Multicriteria selection practices in public tender evaluation process: the case of Sri Lanka

PurposeAwarding contracts based solely on the lowest price is unsuitable for every project. Consequently, most procurement systems in developed countries have progressed to the multicriteria selection practices (MSPs) for tender evaluation. MSPs consider a range of quality measures, such as completion time, life cycle cost, functional characteristics, environmental impact and innovation, alongside bid price. This study examines the prevailing MSPs in Sri Lankan public tender evaluations to enhance the effectiveness of the local tender evaluation process.Design/methodology/approachA desk study approach was employed to collect bidding documents, resulting in the identification of 66 documents. A systematic screening process was then applied to identify those bidding documents that incorporated MSPs. Subsequently, content analysis was conducted to determine the common features of the functions used in MSPs.FindingsThe study identified six primary functions related to MSPs incorporated in the bidding documents to procure building and substation projects. Three functions follow the price-to-quality method, while the remaining three follow the quality-to-price method. Among these identified functions, four functions employ objective evaluation criteria, such as thickness, capacity and operational loss. The other two functions utilize subjective evaluation criteria, such as the project’s design and technical specifications. Contract awarding will be based on either the highest score or the lowest bid, depending on the function type.Originality/valueThis study’s originality lies in exploring MSPs in the Sri Lankan public tender evaluation process and in disclosing their characteristics to promote the MSPs in Sri Lanka and developing countries.

Myopic Maculopathy Stabilization in a Child with Progressive Complicated Myopia and Underlying Connective Tissue Dysplasia via Optical Therapy with HAL Spectacle Lenses Inducing Retinal Peripheral Defocus: Clinical Case

Background. Myopia is a serious medical and social problem specifically due to the high risk of such complications as cataracts, myopic maculopathy, glaucoma, and retinal detachment. Children with connective tissue dysplasia (CTD) syndrome are most subjected to myopia. Prevention of myopia progression in children remains the only effective way to prevent myopic maculopathy. Significant progress in this field has been achieved via optical technologies developed on the basis of peripheral defocus theory. Clinical case description. Patient, 10 years old, with CTD, mild myopia of both eyes with rapid progression, myopic maculopathy, grade 1. Ophthalmic status: spheroequivalent refraction — right eye (–)1.5 diopters / left eye (–)1.75 diopters; vision acuity with monocular correction — 1.0. Fundoscopy: optic disc is pale pink, with clear borders, arteries and veins are well-proportioned, their courses and calibers are intact; choriocapillary layer attenuation in the macular and paramacular zones, “parquet fundus”; areas of pigment redistribution on peripheral retina; no atrophic foci detected; anterior-posterior axis of the right and left eyes — 26.2 and 26.3 mm, respectively. Optical coherence tomography (OCT) has revealed retinal thinning in the upper and nasal sectors in the right eye during the first assessment. The left eye has demonstrated losses of retinal thickness within the middle parafoveal zone and significant thinning in the upper segment. Optical therapy with HAL spectacle lenses (inducing volumetric myopic peripheral defocus) was assigned to control myopia to slow down the pathological axial growth of the child's eyes and to stabilize refraction. 4 months of wearing glasses with HAL lenses has led to the stabilization of dystrophic changes in retina, signs of improvement in several sectors by were observed on OCT. No negative changes were revealed in all parafoveal segments of the left eye. The child was recommended to continue wearing glasses with HAL lenses with dynamic follow-up every 3 months. Conclusion. CTD in children is associated with high risk of complications in case of myopia progression, moreover, retinal pathology can occur even with mild myopia. Optical therapy with HAL spectacle lenses is effective and safe first treatment of choice in the control of myopia in children with CTD, and opens new opportunities in prevention of progressive myopia disabling complications in children, whose treatment results were not previously sufficient.

Predicting the thickness loss and recovery of acrylic carpet pile imposed to UV exposure using artificial intelligence

One of the metrics that establishes the carpet quality is its compress and decompress behaviors. In a research, addressed later in the paper, carpet samples with the acrylic pile were exposed to the ultraviolet (UV) exposure for 0, 8, 12, 16, and 20 h. The wear test was then carried out using drum revolutions of 0, 4000, 6000, and 8000. Following that, the samples were subjected to a static stress of 700 KPa for 2 h. After removing the load, the sample thickness was measured every 2 min. Finally, the thickness loss and recovery features were determined. Now in this study, the statistical analysis demonstrated the significance of recovery time, UV exposure, and drum revolutions on the features mentioned above, and in the next step, they were modeled using an artificial neural network (ANN) structure. The genetic algorithm, particle swarm optimization, and gray wolf optimization (GWO) were applied as the alternatives to the backpropagation (BP) algorithm for updating the weights and biases of ANN. In the end, it was found that the thickness loss and recovery could be predicted with 6.92 and 9.14% errors, using ANN-GWO and ANN-BP-GWO, respectively.

Orientation effect of chopped steel fiber on tribological performance of very low metallic brake pads: An interface study

The orientation effect of chopped tiny steel fibres (length &lt; 3 mm; diameter &lt; 200 µm) in brake pads parallel (NAPA) to the sliding direction is studied using two different methods. Inverting the specimen during testing yields fibre perpendicular (NAPE) to the sliding direction, which is compared to commercial random-oriented fibre pads (NARA). The orientation coefficient value of near unity is achieved only in NAPA. NAPA and NAPE have a lower density than NARA by 13.2% due to less than 54.55% of steel fibres in the formulation. More and larger plateaus stabilized friction in NARA, utilising the elongation properties of parallel steel fibres, than in NAPE, which produced only tiny plateaus. However, the wear resistance decreases when the sliding path or direction changes from parallel to perpendicular. The measurement of thickness loss is misleading during wear because of the swelling effect, and hence energy requirements are considered. The energy required to wear 1 cc of specimen in the NAPE is 23.78% greater than that in the NAPA, and hence wear resistance is better. Adhesion followed by delamination at elevated temperatures are the dominant wear mechanisms in NAPA, whereas abrasion is dominant in NAPE. Thus, semi-metallic performance can be obtained in a very low metallic pad by orienting these fibres.

Methylene Blue Reduces Electroretinogram Distortion and Ganglion Cell Death in a Rat Model of Glaucoma.

Glaucoma is the second leading cause of blindness worldwide and is, in most cases, a consequence of elevated intraocular pressure (IOP), ultimately resulting in the death of retinal ganglion cells (RGCs). Current treatments are mostly focused on normalizing IOP, but we propose the additional use of neuroprotective agents, including methylene blue (MB), to block the loss of RGCs. Wistar rats were subjected to episcleral vein cauterization (EVC) in the left eye while the right eye was sham-operated. One week later, they were divided into two groups, which were injected with either 2.0 mg/kg MB or phosphate-buffered saline (PBS), twice a day, for 7 days. Fifteen days after surgery, rats were tested with scotopic electroretinography (ERG) or pattern electroretinography (PERG). After sacrifice, the number of RGCs and the thickness of the inner retina (IR) were evaluated both in the peripheral and central areas of the retina. Scotopic ERG showed a marked reduction (p < 0.0001) on the a- and b-wave amplitude and oscillatory potential (OP) complexity of the eyes subjected to EVC. These parameters were significantly (p < 0.01) restored by the application of MB. PERG indicated that EVC was responsible for a very significant decrease in N2 amplitude (p < 0.0001) and prolongation of N2 implicit time (p < 0.0001). Treatment with MB significantly restored N2 amplitude (p < 0.0001). In parallel with the ERG results, morphological analysis showed a significant loss of RGCs (p < 0.0001) and IR thickness (p < 0.0001) in both the peripheral and central retinas subjected to EVC, which was significantly prevented (p < 0.0001) by MB treatment. We have shown that MB treatment can be effective in preventing physiological and morphological hallmarks of optic neuropathy in a model of ocular hypertension, which faithfully recapitulates human open-angle glaucoma. Due to its high safety profile, this drug could therefore represent a new pharmacologic strategy to prevent vision loss in glaucoma patients.

Randomized, controlled, within-patient, single-blinded pilot study to evaluate the efficacy of 12-weeks of endermotherapy with adult burn survivors

BackgroundVacuum massage, or endermotherapy, is applied to scar tissue with the primary therapeutic goal of promoting structural or physiological changes. These changes are intended to enhance pliability, enabling the skin to possess the strength and elasticity required for normal mobility. The advantage of vacuum massage compared to therapist-generated manual massage is that it provides a standardized dosage using rollers and suction valves to mobilize the tissue. However, research documenting and supporting its impact on post-burn hypertrophic scar is lacking. Thus, this study was designed to objectively characterize the changes in scar elasticity, erythema, melanin, thickness, and transepidermal water loss immediately after a vacuum massage session and after a 12-week course of treatment compared to intra-individual matched control scars. MethodsWe conducted a prospective, randomized, controlled, within-patient, single-blinded clinical trial, initially designed as a fully-powered study but limited to a pilot study due to COVID-19 restrictions. Nineteen burn survivors consented to participate and 16 completed the study. Two homogeneous, intra-individual scars were randomized to usual care control or vacuum massage therapy plus usual care. Vacuum massage interventions were provided by a certified massage therapist three times per week for 12 weeks. Scar characteristics were evaluated every four weeks immediately before and after mechanical massage treatment. The evaluations included measurements of elasticity (Cutometer), erythema and melanin (Mexameter), transepidermal water loss (TEWL) (Tewameter), and thickness (high-frequency ultrasound). Linear mixed-model analyses were performed to test for immediate and long-term treatment effects. ResultsThe ANOVA analyses revealed a non-significant time:treatment interaction for elasticity, erythema, melanin, thickness, or TEWL. There was a significant increase in elasticity and erythema and a decrease in TEWL in both the control and treatment sites over time with consistent standard care. However, there was no statistically significant immediate or long-term treatment effect for any of the skin characteristics. Nonetheless, the mean participant satisfaction was 4/5 (SD = 1.5) and the mean participant perception of effectiveness was 8/10 (SD = 1.9). ConclusionsThis pilot study did not find a treatment benefit of vacuum massage therapy for elasticity, erythema, melanin, thickness or TEWL, but it did find an improvement with time in elasticity, erythema and TEWL. Despite the lack of objective improvement of the treated scar site, participants were satisfied with the results and believed vacuum massage was very effective. Further high-quality research is required to better inform clinicians patient education and treatment decisions for this costly, burdensome treatment approach that has high participant satisfaction.